Nihon Kyobu Shikkan Gakkai Zasshi, 1997 Jan, 35(1), 67 - 71 {Spontaneous recovery from cytomegalovirus pneumonia}; Matsuki H et al.; A 30-year-old woman with systemic lupus erythematosus was admitted to our hospital because of a slight fever and diffuse interstitial shadows on a chest X-ray film . She had taken prednisolone (60 mg per day) at another hospital for six weeks . At the time of admission to our hospital, she had been treated with antituberculosis drugs (streptomycin, isoniazid, and rifampicin) for two weeks because of suspected miliary tuberculosis . Chest radiography on admission revealed diffuse nodular and micronodular shadows in the middle and lower lung fields on both sides . Examination of transbronchial lung biopsy specimens revealed intranuclear viral inclusion bodies in infected alveolar epithelial cells, which suggested the diagnosis of cytomegalovirus infection . The elevation of serum IgM antibody to cytomegalovirus and positive results of in situ hybridization for cytomegalovirus DNA supported this diagnosis . The symptoms and radiographic abnormalities resolved completely without ganciclovir . Although we cannot exclude the possibility that the antituberculosis drugs caused the resolution of the cytomegalovirus pneumonia, it appears most probable that the cytomegalovirus pneumonia resolved spontaneously. Curr Eye Res, 1997 Jan, 16(1), 64 - 70 Effect of electric pulses and antiproliferative drugs on cultured bovine retinal pigment epithelial cells; Oshima Y et al.; PURPOSE: The effect of antiproliferative agents with high voltage electric pulses (EP) on the proliferation of retinal pigment epithelial (RPE) cells was investigated . METHODS: Bovine RPE cells were cultured and exposed briefly to an antiproliferative agent: 0.005 to 500 microM of bleomycin (BLM), 0.005 to 500 microM of mitomycin C (MMC) or 0.05 to 5000 microM of 5-fluorouracil (5-FU) with or without high voltage electric pulses (EP: 2,000V/cm, 98 microseconds, 8 pulses) . Streptomycin (SM) was used as a negative control . Cell proliferation with or without antiproliferative agents was assessed on day 3 . DNA fragmentation was assessed by flow cytometric analysis . RESULTS: Treatment with BLM, MMC or 5-FU inhibited cell proliferation in a dose-dependent manner, with and without EP (p < 0.05) . EP enhanced the inhibitory effect of BLM as much as 3,000 times (ID50: BLM without EP; 163.7 microM, BLM with EP; 0.0574 microM, MMC without EP; 132.4 microM, MMC with EP; 26.2 microM, 5-FU without EP; 616.4 microM, 5-FU with EP; 873.8 microM) . EP treatment showed an inhibitory effect of BLM on cell proliferation more prominently than BLM alone . The cell numbers of 0.5 microM BLM treatment without EP were 87.4 +/- 11.7% (mean +/- SD), whereas the cell numbers of 0.5 microM BLM with EP were 21.1 +/- 2.16% (p < 0.005) . BLM treatment with EP increased the apoptosis like DNA fragmentation in the flow cytometric DNA histogram, showing dominant accumulation in the A0 region, which is the population of DNA fragmentation . (The cell population of the A0 region: control, 3.4%; EP alone, 18.9%; BLM treatment without EP, 32.0%; with EP, 93.8%.) CONCLUSIONS: EP treatment enhances the inhibitory effect of BLM on RPE cell proliferation . The combination of electric pulse and BLM treatment can localize the drug effect and reduce the necessary dose of the antiproliferative agent in comparison to BLM treatment alone. J Bacteriol, 1997 Jan, 179(1), 180 - 6 Use of rpsL for dominance selection and gene replacement in Streptomyces roseosporus; Hosted TJ et al.; We developed a gene replacement system using the rpsL gene of Streptomyces roseosporus and demonstrated its utility by constructing a deletion in the S . roseosporus glnA gene . A 1.3-kb BamHI fragment that hybridized to the Mycobacterium smegmatis rpsL gene was subcloned from an S . roseosporus cosmid library and sequenced . Plasmid pRHB514 containing the rpsL gene conferred streptomycin sensitivity (Sm(S)) to the Sm(r) S . roseosporus TH149 . The temperature-sensitive plasmid pRHB543 containing rpsL and the S . roseosporus glnA gene disrupted with a hygromycin resistance (Hm(r)) gene was introduced into S . roseosporus TH149, and recombinants containing single and double crossovers were obtained after a temperature increase . Southern hybridization analysis revealed that single crossovers occurred in the glnA or rpsL genes and that double crossovers resulted in replacement of the chromosomal glnA gene with the disrupted glnA . Glutamine synthetase activity was undetectable in the recombinant containing the disrupted glnA gene. Drug Saf, 1996 Dec, 15(6), 394 - 405 Hepatotoxicity of antitubercular treatments . Rationale for monitoring liver status; Durand F et al.; The standard antitubercular regimen currently includes a combination of 3 antitubercular agents: isoniazid, rifampicin (rifampin) and pyrazinamide . Administration of a fourth agent, ethambutol, is recommended when isoniazid resistance is suspected . Two of these 4 agents (isoniazid and pyrazinamide) are major hepatotoxins . The remaining 2 agents (rifampicin and ethambutol) are rarely or not hepatotoxic . However, rifampicin, which is a powerful enzyme inducer, may enhance the hepatotoxicity of isoniazid . In patients receiving a combination of isoniazid, rifampicin and pyrazinamide, 2 patterns of fulminant liver injury can be observed . The first pattern is characterised by an increase in serum transaminase activity that occurs soon (usually within the first 15 days) after initiation of treatment . This pattern is likely to be caused by rifampicin-induced isoniazid hepatotoxicity . The prognosis is good in most cases . The second pattern is characterised by an increase in serum transaminase activity that occurs late (usually more than 1 month) after the initiation of treatment . It has been suggested that this pattern may be related to pyrazinamide hepatotoxicity . The prognosis of this type of hepatitis is generally poor . In order to reduce the risk of severe hepatic adverse effects during antitubercular treatment, several measures are proposed . First, patients with underlying liver test abnormalities should not be given pyrazinamide . Second, isoniazid and pyrazinamide should be administered at the lowest dosage within their respective therapeutic ranges . Third, serum transaminase levels should be determined twice weekly during the first 2 weeks of treatment, every 2 weeks during the rest of the first 2 months, and every month thereafter . When serum transaminase levels increase to greater than 3 times the upper limit of normal, therapy with isoniazid, rifampicin and pyrazinamide should be stopped . After serum transaminase levels have returned to normal, isoniazid can be re-introduced at a low daily dose, without rifampicin . Pyrazinamide may not be re-introduced because of the risk of recurrence and the poor prognosis of pyrazinamide-induced hepatitis . Although it is nephrotoxic, streptomycin is an alternative in patients with liver test abnormalities during antitubercular treatment. Ned Tijdschr Geneeskd, 1996 Nov 2, 140(44), 2187 - 91 {Drug resistance in Mycobacterium tuberculosis in The Netherlands}; Lambregts-van Weezenbeek CS et al.; OBJECTIVE: To determine magnitude, trend and specific features of the resistance problem . DESIGN: Descriptive . SETTING: Royal Netherlands Tuberculosis Association, The Hague, the Netherlands . METHODS: The data of the National Institute of Public Health and Environmental Protection concerning the prevalence of drug-resistant tuberculosis during the period 1990-1994 were analysed . Also, features of patients with and without drug resistance were compared (Dutch National Tuberculosis Register: cohort 1993) . RESULTS: Isoniazid and streptomycin resistance were each observed in approximately 6% of susceptibility tests, showing no clear trend over the study period . Rifampicin resistance increased from 0% to 1.5% in 1994 . In the 1993 patient cohort, 809 cases were analysed, showing resistant organisms in 103 (13%) . The resistance group included 84 (82%) foreigners versus 387 (55%) among the 'sensitives' (p < 0.001) . The percentages of (known) HIV infections were equal in both groups (5-6%) . The percentage of isoniazid-resistance varied from 1.8% in Dutch patients to 7.8% in foreign patients . Recent immigrants and refugees waiting for official status were important risk groups for resistance (p < 0.005) . Foreign tuberculosis patients defaulted more often from treatment than Dutch patients (p < 0.001) . CONCLUSION: Drug-resistant tuberculosis in the Netherlands is mainly due to import of resistant strains . Transmission and further development of resistance within the country must be prevented. Trans R Soc Trop Med Hyg, 1996 Nov-Dec, 90(6), 692 - 5 Resistance to antituberculosis drugs in rural South Africa: rates, patterns, risks, and transmission dynamics; Wilkinson D et al.; This study describes the rate, pattern, and transmission dynamics of, and risk factors for, isolates of Mycobacterium tuberculosis resistant to antituberculosis drugs in a rural South African health district . Twenty-one of 254 (7.6%; 95% confidence interval {CI} 4.8-11.4) isolates from incident cases were resistant to at least one drug (isoniazid, rifampicin, streptomycin, ethambutol) . A random sample of 28 otherwise susceptible isolates and all 21 resistant isolates were susceptible to pyrazinamide . There was one case of combined isoniazid/rifampicin resistance . The rate of initial resistance was 8.1% (95% CI 4.9-12.4) and of acquired resistance 6.2% (95% CI 1.9-14.2) . Age, sex, known human immunodeficiency virus status, and previous treatment history were not associated with drug resistance . Restriction fragment length polymorphism (RFLP) analysis of 13 of the 21 resistant specimens showed 12 different banding patterns . Rates of drug resistance were low in this representative sample of patients from a defined geographical area . Previous treatment history was probably not a risk factor because of the use of multiple drug regimens, directly observed therapy, and high completion rates in those previously treated . Although limited in number, the RFLP data suggested that recent local transmission of resistant strains was not occurring to a significant extentPIP: Drug resistance in patients with tuberculosis (TB) is a cause of treatment failure and relapse, and contributes to the development of multiple-drug resistance . Consecutive incident adult patients diagnosed with sputum smear-positive TB during 1994 in Hlabisa Hospital, northern KwaZulu/Natal, were studied to describe the rate, pattern, and transmission dynamics of, and risk factors for, isolates of Mycobacterium tuberculosis resistant to antituberculosis drugs . Cases currently being treated and followed were excluded from study . There were 354 incident cases of sputum smear-positive pulmonary TB registered at the hospital in 1994, although sputum specimens for culture were obtained from only 335 patients . 21 isolates from incident cases were at least partially resistant to at least either isoniazid, rifampicin, streptomycin, or ethambutol . A random sample of 28 otherwise susceptible isolates and all 21 resistant isolates were susceptible to pyrazinamide . There was one case of combined isoniazid/rifampicin resistance . The rates of initial and acquired resistance were 8.1% and 6.2%, respectively . Age, sex, known HIV status, and previous treatment history were not associated with drug resistance . Restriction fragment length polymorphism (RFLP) analysis of 13 of the 21 resistant specimens identified 12 different banding patterns, suggesting the absence of any significant recent local transmission of resistant strains . Acta Otolaryngol, 1996 Nov, 116(6), 812 - 6 Incorporation of tetracycline into otoconia of the guinea-pig following streptomycin intoxication; Zhang DM et al.; The effects of streptomycin on the calcium ion turnover into otoconia of adult guinea-pigs investigated by the use of tetracycline . The oral administration of tetracycline induced the deposition of tetracycline (fluorescence) on the outer surface of otoconia indicating the existence of dynamic exchange and/or uptake of calcium ions in the otoconia . The significant finding is that streptomycin specifically interfered with calcium uptake into the otoconia which indicated that the decrease in calcium uptake caused by streptomycin may be closely related to the loss of otoconia as well as to a decrease in the calcium contents of otoconia . The decrease in calcium incorporation into otoconia caused by streptomycin was recovered within 6 weeks after the last injection of streptomycin . The number of otoconia with fluorescence in the central portion as well as their outer surface was increased . It is therefore suggested that the recovery of calcium uptake as well as new otoconial regeneration may play an important role for the recovery from loss of otoconia. J Bacteriol, 1996 Nov, 178(22), 6496 - 507 Biosynthesis of diaminopimelate, the precursor of lysine and a component of peptidoglycan, is an essential function of Mycobacterium smegmatis; Pavelka MS Jr et al.; Diaminopimelate (DAP) is a unique metabolite used for both the biosynthesis of lysine in bacteria and the construction of the peptidoglycan of many species of bacteria, including mycobacteria . DAP is synthesized by bacteria as part of the aspartate amino acid family, which includes methionine, threonine, isoleucine, and lysine . Aspartokinase, the first enzyme in this pathway, is encoded by the ask gene in mycobacteria . Previous attempts to disrupt this gene in Mycobacterium smegmatis were unsuccessful, even when the cells were supplied with all the members of the aspartate family, suggesting that unlike other bacteria, mycobacteria may have an absolute requirement for this pathway even when growing in rich medium containing DAP . The purpose of this study was to determine if the ask gene and the aspartate pathway are essential to M . smegmatis . This study describes a test for gene essentiality in mycobacteria, utilizing a counterselectable marker (streptomycin resistance) in conjunction with a specially constructed merodiploid strain . We have used this system to show that the ask gene could not be disrupted in wild-type M . smegmatis, using selective rich medium supplemented with DAP unless there was an extra copy of ask provided elsewhere in the chromosome . Disruption of ask was also possible in a lysine auxotroph incapable of converting DAP to lysine . The ask mutant, mc21278 (ask1::aph), exhibits multiple auxotrophy (Met-, Thr-, DAP-, and Lys-) and is complemented by the ask gene . This is the first description of DAP auxotrophy in mycobacteria . The ask mutant lyses when deprived of DAP in culture, a characteristic which can be exploited for the reproducible preparation of protoplasts and mycobacterial extracts . The evidence presented here indicates that the aspartate pathway is essential to M . smegmatis and that DAP is the essential product of this pathway. J Neurophysiol, 1996 Nov, 76(5), 3301 - 12 Hair cell regeneration and recovery of the vestibuloocular reflex in the avian vestibular system; Carey JP et al.; 1 . Although auditory and vestibular hair cells are known to regenerate after aminoglycoside intoxication in birds, there is only sparse evidence that the regenerated hair cells are functional . To address this issue, we examined the relation of hair cell regeneration to recovery of the vestibuloocular reflex (VOR), whose afferent signal originates at hair cells in the vestibular epithelium . Hair cell damage was produced by treating white Leghorn chicks (Gallus domesticus, 4-8 days posthatch) with streptomycin sulfate in normal saline (1,200 mg.kg-1.day-1 im) for 5 days . 2 . In the 1st wk after treatment, the VOR gain was essentially 0, and hair cell density as assessed by light microscopy was approximately 40% of normal . Between the 1st and 3rd wk after treatment, the VOR was present . Although VOR gain varied considerably from one chick to another, it increased, on average, between the 1st and 3rd wk, as did the average hair cell density . At the end of 8-9 wk, the gain and phase of the VOR had returned to normal values, as had the average density of hair cells . 3 . Therefore, despite the catastrophic initial effect of hair cell loss on the VOR, recovered hair cells appeared to restore the VOR completely . Average hair cell density increased with average VOR gain . VOR gain correlated better with recovery of type 1 hair cells than with recovery of type II hair cells . 4 . In contrast to hair cell density, the appearance of the vestibular epithelia as assessed by hair cell stereocilia in scanning electron micrographs was a poor indicator of VOR gain . In both treated and control birds, epithelia with the same appearance could have quite different VOR gains, suggesting a variation in the functional viability of the hair cells . 5 . This observation suggests that several factors, such as the repair of stereocilia, the efficacy of hair cell synapses on afferent fibers, and the extent of compensation by central vestibular pathways, may affect the recovery of VOR gain . However, our data suggest that hair cell regeneration plays an important role in this recovery. Antimicrob Agents Chemother, 1996 Nov, 40(11), 2452 - 4 Correlation of molecular resistance mechanisms and phenotypic resistance levels in streptomycin-resistant Mycobacterium tuberculosis; Meier A et al.; Quantitative susceptibility testing of clinical isolates of streptomycin-resistant Mycobacterium tuberculosis demonstrated that there is a close correlation between the molecular resistance mechanism and the in vitro activity of streptomycin: mutations in rpsL were mainly associated with high-level resistance, mutations in rrs were associated with an intermediate level of resistance, and streptomycin-resistant isolates with wild-type rpsL and rrs exhibited a low-level resistance phenotype . Investigations of streptomycin-resistant isolates with wild-type rpsL and rrs revealed that (i) there is no cross-resistance to other drugs and (ii) a permeability barrier may contribute to resistance, because resistance was significantly lowered in the presence of a membrane-active agent. Am J Respir Crit Care Med, 1996 Nov, 154(5), 1473 - 7 Rifampin preventive therapy for tuberculosis in Boston's homeless; Polesky A et al.; An epidemic of isoniazid (INH)- and streptomycin (SM)-resistant tuberculosis began among Boston's homeless population in 1984 . Individuals with skin test conversions who agreed to preventive therapy received either INH, rifampin, or a combination of INH and rifampin . A total of 204 individuals with documented tuberculin skin test conversions who did not have active tuberculosis at the time of the clinical evaluation for their positive skin test were eligible for preventive therapy . Data on type and length of preventive therapy were obtained from the Tuberculosis Clinic and the Boston Tuberculosis Registry records at Boston City Hospital . The individuals were followed for development of active tuberculosis . Six of 71 (8.6%) individuals who received no therapy, 3 of 38 (7.9%) in the INH group, and none in the rifampin or rifampin plus INH groups (49 and 37 persons, respectively) developed active tuberculosis . Patients in the rifampin group were significantly less likely to develop tuberculosis than patients in the no therapy group (p = 0.04; odds ratio {OR} = 0.00, 95% confidence interval {CI} = 0.00-0.91) . Treatment with any rifampin-containing preventive therapy (rifampin or rifampin plus INH) was effective (p < 0.01 ) in preventing development of active disease . The three INH failures were with organisms that were resistant to INH. Recenti Prog Med, 1996 Oct, 87(10), 457 - 9 {Tuberculosis and immigrants . A study of its prevalence in the Umbria region}; Cerami F et al.; In 1995, 463 patients were admitted in the medical service of Perugia (Sanitary District n . 6) . Only 20% of them were enrolled in the TBC programme . Mantoux was: < 10 mm in 35%, 10-15 mm in 25%, > 15 mm in 40% . Chest Rx in 30 subjects demonstrated: normality in 19; old TBC in 7, active TBC in 4 (miliary, bilateral upper lobe pneumonitis, left subapical upper lobe pneumonitis and right lobitis of the upper lobe) . All patients were admitted in hospital and showed positive sputum culture for Mycobacterium Tuberculosis . They were treated with isoniazid, rifampin, pyrazinamide, ethambutol/streptomycin for 2 months and with isoniazid, rifampin for other 4-8 months . Two patients showed Mycobacterium tuberculosis with isoniazid resistance . Seven patients were treated with isoniazid chemoprophylaxis without side effects . Migrants should receive information about health care service and be encourage to register themselves with a general practitioner . Skin test screening and chest radiographs for those with positive results should be provided at a convenient location. J Craniomaxillofac Surg, 1996 Oct, 24(5), 289 - 92 Use of streptomycin-lidocaine injections in the treatment of the cluster-tic syndrome . Clinical perspectives and a case report; Kreiner M; Trigeminal neuralgia and cluster headache syndrome are complex pain conditions of the craniofacial region . Both diseases can coexist in the same patient, comprising the cluster-tic syndrome . This article reviews the literature on this condition and reports a new case who responded well to peripheral streptomycin-lidocaine injections. J Acquir Immune Defic Syndr Hum Retrovirol, 1996 Oct 1, 13(2), 155 - 9 Human immunodeficiency virus infection in children with tuberculosis in Santo Domingo, Dominican Republic: prevalence, clinical findings, and response to antituberculosis treatment; Espinal MA et al.; We studied human immunodeficiency virus (HIV)-seroprevalence among children with clinically diagnosed tuberculosis (TB) and compared the clinical features and response to short-term anti-TB therapy of children with and without HIV infection in Santo Domingo, Dominican Republic . Children aged 18-59 months with new-onset, clinically diagnosed TB were tested for HIV antibodies, their clinical features were recorded and their response to a standard 6-month regimen of daily isoniazid and rifampicin with daily streptomycin and pyrazinamide for the first 2 months was assessed . To increase the number of HIV-infected children with TB available for study, we also included children previously known to be HIV infected who developed new-onset TB . Eleven (5.8%) of 189 consecutively enrolled children with clinically diagnosed TB were HIV infected . Fifteen other children with previously documented HIV infection and new-onset TB were available for study, yielding 26 HIV-positive and 178 HIV-negative children with TB . Of these 204 children with clinically diagnosed TB, 25 HIV-positive and 156 HIV-negative children were successfully followed for 6 months or until death . The proportion of HIV-positive children who failed treatment was 6 (29%) of 21 as compared with only 5 (3%) of 156 HIV-negative children {relative risk = 8.9; 95% confidence interval (CI) 2.9, 26.6; p = 0.0004} . HIV-infected children with clinically diagnosed TB are substantially more likely to fail standard treatment for TB than are HIV-uninfected children . If standard treatment regimens are used in such children, response to treatment must be monitored very closely and appropriate changes in the regimen must be made expeditiously. Arch Otolaryngol Head Neck Surg, 1996 Sep, 122(9), 1001 - 4 Audiovestibular findings in patients with deafness caused by a mitochondrial susceptibility mutation and precipitated by an inherited nuclear mutation or aminoglycosides; Braverman I et al.; OBJECTIVE: To characterize the audiological and vestibular changes associated with a mitochondrial DNA mutation in an Arab-Israeli family and in other families with mitochondrial predisposition to aminoglycoside-induced hearing loss . DESIGN: Evaluation of audiological (pure tone thresholds, speech reception thresholds, speech discrimination, tympanometry, acoustic reflex thresholds, tone decay, and auditory brain-stem evoked response recording) and vestibular (complete history, physical examination, and 2-channel electronystagmography) systems . In 5 patients, structural evaluation of the inner ear was done by magnetic resonance imaging . PATIENTS: Fifteen members of an Arab-Israeli family, and 1 Chinese woman with the same mitochondrial DNA mutation who experienced hearing loss after short-term exposure to streptomycin . RESULTS: Most of the patients had a profound hearing loss due to cochlear involvement . The hearing loss usually was not accompanied by notable peripheral vestibular dysfunction . In the patient with severe hearing loss after exposure to aminoglycoside, the vestibular function was completely normal . CONCLUSIONS: In most of the Arab-Israeli patients with congenital deafness, the vestibular system function was normal, in contrast to the frequency of vestibular abnormality among deaf children, which was described in the literature . This may be related to genetic predisposition to aminoglycoside-induced deafness. Spine, 1996 Aug 15, 21(16), 1898 - 903 Duration of antituberculosis chemotherapy in conjunction with radical surgery in the management of spinal tuberculosis; Upadhyay SS et al.; STUDY DESIGN: The effectiveness of duration of antituberculous chemotherapy in conjunction with radical surgery for tuberculosis of the spine is reported . One hundred fourteen patients were followed prospectively for a mean period of 14.6 years after radical resection of the tuberculous lesion and reconstruction of the resultant gap with bone graft . OBJECTIVE: To evaluate the efficacy of short-course antituberculous chemotherapy in relation to the standard 18-month chemotherapy in conjunction with radical surgery for tuberculosis of the spine . SUMMARY OF BACKGROUND DATA: One hundred fourteen patients who were subjects of the Medical Research Council's (London, UK) prospective study underwent radical resection of the lesion and anterior arthrodesis of the spine . These patients received 6, 9, and 18 months of antituberculous chemotherapy . Those who received 6- and 9-month chemotherapy received streptomycin, rifampicin, and isoniazid . Streptomycin was given for the first 3 months, and the other two drugs were continued for 6 or 9 months . Those who received 18 months of chemotherapy were given streptomycin (first 3 months), sodium para-aminosalicylic acid, and isoniazid . METHODS: These patients were followed longitudinally, and at each visit, clinical and radiologic data were collected at 1-month intervals up to 3 months postoperatively, at 3-month intervals to 30 months postoperatively, at 6-month intervals up to 5 years postoperatively, and at 12-month intervals to the conclusion of study (minimum, 10 years) . For assessment of spinal deformity, the "deformity angle" was measured on lateral spinal radiographs obtained at each visit . RESULTS: Six-month, 9-month, and 18-month chemotherapeutic regimens in association with radical surgery produced similar clinical results with no recurrence or reactivation of tuberculosis . The changes in deformity angles at final follow-up evaluation compared with 6-month postoperative values were not statistically significantly different in the groups who underwent 6 months, 9 months, and 18 months of chemotherapy . CONCLUSIONS: The authors' findings show that a 6-month chemotherapeutic regimen combined with surgical excision and bone grafting is adequate for management of tuberculosis of the spine, as it produced clinical and radiologic results comparable with the 18-month chemotherapeutic regimen. J Invest Dermatol, 1996 Aug, 107(2), 229 - 34 In the absence of streptomycin, minoxidil potentiates the mitogenic effects of fetal calf serum, insulin-like growth factor 1, and platelet-derived growth factor on NIH 3T3 fibroblasts in a K+ channel-dependent fashion; Sanders DA et al.; There is considerable evidence to suggest that the opening of K+ channels plays an important role in stimulating mitogenesis . K+ channel blockers have been shown to inhibit mitogenesis in vitro, mitogens increase cytosolic membrane K+ channel permeability, K+ channel openers stimulate hair growth in vivo, and the Ras/Raf signal transduction pathway induces K+ channel activity . Paradoxically, however, K+ channel openers such as minoxidil have been reported in vitro not to modulate, or even to inhibit, mitogenesis in a range of cell types . Only untherapeutic concentrations have stimulated mitogenesis . These experiments, however, appear to have been carried out in the presence of aminoglycoside antibiotics, which inhibit potassium channel activity . We now report that in the absence of aminoglycoside antibiotics, minoxidil at 10 microg/ml (0.05 mM) causes a significant stimulation of proliferation of NIH 3T3 fibroblasts maintained over a 10-d period in 5% fetal calf serum-supplemented medium . Further, we show that in the presence of 100 microg streptomycin per ml, minoxidil at 10 microg/ml produces an initial inhibition of proliferation, which apparently confirms, in NIH 3T3 fibroblasts, that the inhibition of mitogenesis by minoxidil in the presence of streptomycin is an artifact . The potentiation of NIH 3T3 cell growth by minoxidil can be attributed to the opening of potassium channels, because the potassium channel blocker tolbutamide (5 mM) or combinations of the blockers tolbutamide (1 mM)/tetraethylammonium (2 mM) or glibenclamide (1 microM)/apamin (10 nM) block the minoxidil-induced stimulation of growth . We also demonstrate that minoxidil is able to significantly potentiate the mitogenic effects of both platelet-derived growth factor and insulin-like growth factor 1 on NIH 3T3 fibroblasts in the presence of CPSR-2 (a cytokine free serum substitute) . Thus we have shown that minoxidil potentiates the mitogenic effects of fetal calf serum in vitro on NIH 3T3 fibroblasts by opening potassium channels and is also able to potentiate the mitogenic effects of the growth factors platelet-derived growth factor and insulin-like growth factor 1. Avian Dis, 1996 Jul-Sep, 40(3), 533 - 9 Analysis of plasmids cloned from a virulent avian Escherichia coli and transformed into Escherichia coli DH5 alpha; Wooley RE et al.; Three of four plasmids from a virulent wild-type avian Escherichia coli were cloned or transformed into an avirulent laboratory recipient E . coli DH5 alpha and tested for the ability to confer a virulence phenotype . The three plasmids transformed into E . coli DH5 alpha were 5, 6, and 56 kb . A fourth plasmid of 64 kb was not successfully transformed . Parameters used to measure virulence included presence of type 1 pili and a smooth lipopolysaccharide (LPS) layer, motility, production of Colicin V, resistance to host complement, and embryo lethality . The 5-kb plasmid encoded for ampicillin resistance, whereas the 6-kb plasmid encoded for tetracycline resistance . The 56-kb plasmid encoded for streptomycin, sulfisoxazole, and tetracycline resistance . Twelve-day embryos inoculated with 467 colony-forming units of E . coli DH5 alpha containing the 56-kb plasmid had increased death rates (45%) in the embryo lethality assay and a decreased weight of surviving embryos with cranial hemorrhages as compared with embryos inoculated with similar amounts of E . coli DH5 alpha (0%) and phosphate-buffered saline (0%) . Embryos inoculated with the wild-type virulent E . coli had 90% deaths . The 56-kb plasmid also had homology with a probe for Colicin V production (cvaC) . No differences in LPS layer, complement resistance, motility, Colicin V activity, type 1 pili, cell-free supernatant proteins, or outer membrane proteins were observed in the transformants when compared with nontransformed E . coli DH5 alpha. Cell Mol Biol (Noisy-le-grand), 1996 Jul, 42(5), 719 - 27 In vitro studies on ppGpp synthetase I from polyamine-starved and unstarved Escherichia coli; Goldemberg SH; We have studied the in vitro formation of guanosine 5'-diphosphate 3'-diphosphate (ppGpp) using a partially purified ppGpp synthetase I (PSI) from Escherichia coli BGA8, a polyamine auxotrophic strain . A comparison of the enzyme obtained from polyamine-supplemented or deprived bacteria showed similar requirements for the reaction, Mg+2 optimum levels and sparing effect of spermidine . No differences in the inhibitory effects of tetracycline, puromycin and fusidic acid were detected either . However, a modified subcellular distribution, as well as a larger specific activity and a larger stimulation by streptomycin was observed when PSI was prepared from polyamine-depleted bacteria . The role of ribosome assembly and subunit distribution on the altered properties of the enzyme are discussed. Cardiovasc Res, 1996 Jul, 32(1), 131 - 7 Previous-beat contraction history is not influenced by mechanosensitive ion channel blockade; Slinker BK et al.; OBJECTIVES: Prior studies have shown that the performance of the left ventricle on any one beat is influenced by the mechanical events of the previous beat, a phenomenon called "previous-beat contraction history" . This previous-beat contraction history, which appears to be an interplay between the mechanical events of one contraction and the activation state of the next contraction, could depend, at least in part, on mechanosensitive ion channels . The purpose of this study, therefore, was to test the hypothesis that mechanosensitive ion channels contribute to previous-beat contraction history: If previous-beat contraction history depends on mechanosensitive ion channels, the magnitude of its effect should be decreased by blocking mechanosensitive ion channels . METHODS: We performed experiments in buffer-perfused isolated rabbit hearts in which left ventricular pressure and volume were controlled with a servo-motor system . We evaluated the pulse interval-dependent expression of previous-beat contraction history under control conditions (no drug) and in the presence of 100 and 500 microM streptomycin, a blocker of mechanosensitive ion channels . RESULTS: Under control conditions, previous-beat contraction history nor its dependence on pulse interval was influenced significantly by either concentration of streptomycin . CONCLUSION: Mechanosensitive ion channels do not play a role in the expression of previous-beat contraction history in the left ventricle of the isolated rabbit heart. J Histochem Cytochem, 1996 Jul, 44(7), 733 - 41 Internalization of styryl dye FM1-43 in the hair cells of lateral line organs in Xenopus larvae; Nishikawa S et al.; We used a fluorescent dye, FM1-43 to investigate mechanotransduction mechanisms in the hair cells of lateral line organs of Xenopus larvae . FM1-43 specifically labeled the hair cells . The photo-oxidation technique was performed with election microscopy to examine the labeling sites and their mechanisms . The results showed that the labeling sites were mitochondria and rough endoplasmic reticulum throughout the cytoplasm . Endocytic activity of the hair cells was limited to endosomes and small granules located at the apical part of the cells . Blockers of the mechanosensitive cation channel (neomycin, gentamicin, streptomycin, and amiloride) effectively inhibited FM1-43 labeling . One of the blockers, amiloride, was found to bind to hair cells when its fluorescence was examined . Divalent cations such as Mg2+ and Ca2+, but not monovalent cations such as Na+ and K+, inhibited FM1-43 labeling when they were added in excess amounts . These results suggest that FM1-43 internalizes hair cells via the putative mechanosensitive cation channel in the plasma membrane. Biochem Biophys Res Commun, 1996 Jun 25, 223(3), 496 - 501 Mutant mtDNA at 1555 A to G in 12S rRNA gene and hypersusceptibility of mitochondrial translation to streptomycin can be co-transferred to rho 0 HeLa cells; Inoue K et al.; Human skin fibroblast line 95-119, which had been isolated from the mother of a Japanese patient with aminoglycoside-induced deafness and a 1555 A to G mutation at 12S rRNA gene in mitochondrial DNA (mtDNA), was used to investigate the relationship between the 1555 mtDNA mutation and its pathogenicity . By the intercellular transfer of mtDNA with or without the 1555 mutation to mtDNA-less (rho 0) HeLa cells, we isolated cybrid clones and found that the mitochondrial translation in a cybrid clone repopulated with the homoplasmic 1555 mutation showed the highest susceptibility to streptomycin . These observations suggest that the genotype of the mutant mtDNA and the phenotype of hypersusceptibility to streptomycin observed in 95-119 fibroblasts were co-transferred simultaneously to rho 0 HeLa cells, supporting the idea that the homoplasmic 1555 mtDNA mutation is involved in the pathogenesis leading to aminoglycoside-induced hearing loss. Southeast Asian J Trop Med Public Health, 1996 Jun, 27(2), 257 - 62 Pulmonary tuberculosis in a BCG vaccinated area: relationship of disease severity with immunological and hematological parameters and drug resistance patterns; Hussain R et al.; Clinical hematological and immunological parameters were studied in a group of 145 pulmonary patients with active tuberculosis, from a defined area of Karachi (Kharadar) belonging to the lower socioeconomic strata . Although clinical symptomatology could not differentiate the extent of lung involvement, a majority (69.6%) of the patients were diagnosed radiologically as having moderately advanced pulmonary disease . The peak number of patients were in their second decade of life . No differences were observed in the extent of disease based on age or gender . All hematological parameters for the group were in the normal ranges except for low levels of hemoglobin (9.58 +/- 1.55 SD; normal range 12-14 mg/dl) and a high ESR (90 +/- 31 SD; normal range 0-13 mm/hour) . A negative correlation of PPD skin test induration (r = 0.21, p = 0.02), and a positive correlation of total white blood cell (r = 0.20; p = 0.015) was observed with the amount of lung tissue involved . The resistance amongst the strains for the four first line anti-tuberculosis agents was found to be: isoniazid = 27.4%; ethambutol = 14.5%; rifampicin = 11.29% and streptomycin = 12.9% . Multi-drug resistance to the most commonly prescribed combination (rifampicin and ethambutol) was 8.06% . Drug resistance patterns to individual drugs were comparable with resistance patterns observed in strains from greater Karachi at The Aga Khan Hospital during the same period . Such studies should provide improved rationale for patients diagnosis and treatment. Am J Respir Crit Care Med, 1996 Jun, 153(6 Pt 1), 1977 - 81 Predictors of survival in human immunodeficiency virus-infected patients with pulmonary tuberculosis . The Makerere University-Case Western Reserve University Research Collaboration; Whalen C et al.; Infection with the human immunodeficiency virus (HIV) has changed both the epidemiology and natural history of tuberculosis . Despite a generally good response to effective antituberculous therapy, the prognosis remains poor . The objective of this analysis was to determine the independent predictors of survival in HIV-infected Ugandan adults with smear-positive pulmonary tuberculosis . A total of 191 HIV-infected Ugandan adults with smear-positive pulmonary tuberculosis were enrolled into a clinical trial of chemotherapy for tuberculosis . The subjects received either rifampin, isoniazid, and pyrazinamide for two months, followed by rifampin and isoniazid for six months (n = 101) or streptomycin, thiacetazone, and isoniazid for two months followed by thiacetazone and isoniazid for eight months (n = 90) . After standard measurements were made at baseline, the group was followed at regular intervals for a mean of 16 months to determine survival . During the course of follow-up, 82 (43%) of the patients died, six within the first month of therapy . The one-year survival proportion was 68% with an estimated median survival of 26 months and did not differ according to treatment regimen . The hazard for death was biphasic, high early in the course of therapy, and then again after about one year . After controlling for the treatment regimen, four independent predictors of survival were found: anergy to purified protein derivative, atypical chest roentgenogram, previous HIV-related condition, and lymphopenia . In this cohort of Ugandan adults, four simple and inexpensive predictors of survival were found . These factors suggest that the degree of immunosuppression was a major determinant of survival. Am J Respir Crit Care Med, 1996 Jun, 153(6 Pt 1), 1766 - 72 Clarithromycin regimens for pulmonary Mycobacterium avium complex . The first 50 patients; Wallace RJ Jr et al.; Intermediate results of the first 50 patients treated with clarithromycin (CLARI) regimens for Mycobacterium avium-intracellulare (MAI) lung disease were evaluated . Patients were HIV negative, and pretreatment isolates were susceptible to CLARI . Patients received CLARI 500 mg twice daily, ethambutol, rifampin (RMP), or rifabutin (RBT) and initial streptomycin, and they were treated until culture-negative 1 yr . Eleven of 50 patients (22%) were dropped in the first 3 mo . Of the remaining 39 patients, 36 (92%) converted their sputa to negative, and 32 (82%) remain culture negative to date . This includes 11 of 16 (69%) with prior drug therapy and 21 of 23 (91%) with no prior therapy . One or more companion drugs were discontinued in 16 of 39 (41%) of patients because of adverse events . Isolates from six of 39 patients (15%) became CLARI-resistant . Of 23 patients who are alive and were culture-negative a mean of 12.0 mo while receiving therapy, all remain culture-negative without therapy a mean of 19.1 mo . Despite reduced CLARI serum levels in patients also receiving RMP, 10 of 13 patients (77%) receiving this regimen were successfully treated . Although not directly compared with previous regimens, the success of this regimen strongly suggests it is superior to previous non-CLARI-containing regimens. Mutat Res, 1996 May 17, 360(1), 1 - 14 A novel positive detection system of in vivo mutations in rpsL (strA) transgenic mice; Gondo Y et al.; To positively detect the in vivo mutations accumulated in different mouse organs, we have developed a transgenic mouse system . This transgenic mouse carried an Escherichia coli (E . coli) plasmid pML4 as a shuttle vector that consisted of a replication origin (ori), the kanamycin-resistant gene (KanR) and the rpsL+ gene (strAS) derived from E . coli . These E . coli elements were expected to be inert in the transgenic mouse system; thus, neutral mutations would be accumulated on the shuttle plasmid in the transgenic mice . The shuttle plasmid vector was recovered from the mouse genomic DNA and introduced into kanamycin-sensitive (KmS) and streptomycin-resistant (SmR) E . coli cells by using electroporation . The original pML4 shuttle plasmid transformed the host E . coli to KmR and SmS, since both the KanR and rpsL genes exhibited dominant traits of KmR and SmS, respectively . On the other hand, when the retrieved pML4 shuttle plasmid carried a mutated rpsL gene, it could be positively detected as both KmR and SmR . Based on this principle, we were able to positively detect the in vivo mutations accumulated in the rpsL transgene of the shuttle vector pML4 integrated into the mouse genome . The total number of rescued shuttle plasmids were counted on the plates containing Km alone, while only mutants were detected on the plates containing both Km and Sm . We have so far established 22 independent transgenic mouse lines that carried up to approx . 750 copies of the shuttle plasmid pML4 in a haploid genome . By using high-copy-number transgenic mouse lines which carried 350 copies or more of the shuttle vector, we also developed a simple and proficient method for retrieving the shuttle plasmid from various tissues of the transgenic mice . The background mutant frequency was approx . 5 x 10(-5) . In order to validate the applicability of the positive-detection transgenic system for the induced mutagenicity assay, methylnitrosourea (MNU) was administered to the transgenic mice, and an increase in the number of mutant frequencies was seen in all tested organs including spleen, liver and brain . The rpsL transgenic mouse system was therefore considered to provide a quick-and-easy risk assessment test for in vivo tissue-specific mutagenicity, using positive detection by streptomycin. Am J Otol, 1996 May, 17(3), 401 - 9 What is the minimal vestibular function required for compensation? Black FO, Wade SW, Nashner LM. Living with an uncompensated, abnormal vestibular system requires oppressive modification of life style and often prevents return to work and activities of daily living . Patients with vestibular abnormalities were studied to determine the minimal residual vestibular function required to achieve compensation . Three groups of patients with (a) complete unilateral loss of vestibular function with normal horizontal canal-vestibulo-ocular (HCVOR) function in the opposite ear, (b) complete unilateral loss with abnormal HCVOR function in the opposite ear, and (c) bilateral reduction of vestibular function from aminoglycoside toxicity underwent vestibuloocular (VOR), optokinetic (OKN), visual-VOR (VVOR), and computerized dynamic posturography (CDP) tests before and after therapeutic procedures . Results suggest that a minimal VOR response amplitude must be present for compensation of VVOR function to occur . The roles of VOR and OKN phase shifts in vestibular compensation are more complicated and require further study . Compensation of vestibulospinal function does not necessarily accompany VOR or VVOR compensation . Ascending and descending vestibular compensatory mechanisms may involve different spatial sensory inputs . Results of these studies have important implications for the diagnosis and treatment of patients with vestibular disorders, including selection and monitoring of patients for therapeutic regimens such as vestibular nerve section and streptomycin therapy. Antimicrob Agents Chemother, 1996 May, 40(5), 1186 - 8 Characterization of streptomycin resistance mechanisms among Mycobacterium tuberculosis isolates from patients in New York City; Cooksey RC et al.; From a collection of 367 isolates of Mycobacterium tuberculosis from patients in New York City in 1994, 45 isolates (12.3%) were resistant in vitro to 2 micrograms or more of streptomycin (SM) per ml . We further evaluated these isolates for levels of SM resistance and for mutations previously associated with resistance in the rpsL (S12 ribosomal protein) gene and the rrs (16S rRNA)-coding region . Twenty-four isolates, representing nine distinct patterns of susceptibility to antituberculosis drugs, were resistant to 500 micrograms of SM per ml and shared a common point mutation at nucleotide 128 in the rpsL gene . This mutation, which substitutes lysine for arginine in the S12 ribosomal binding protein, was not present in isolates with low-level SM resistance or in SM-susceptible control isolates . Among 20 isolates with low-level SM resistance, one possessed a substitution (C-->G865) in the 912 loop of the rrs gene . No mutations in the 530 loop of the rrs coding region were detected, suggesting the presence of an alternative SM resistance mechanism in 19 isolates . Single-strand conformation polymorphisms of mutants were readily detected by a nonradioactive gel screen. J Med Assoc Thai, 1996 May, 79(5), 285 - 7 Effect of isoniazid prophylaxis on incidence of active tuberculosis among Thai HIV-infected individuals; Saenghirunvattana S; A prospective comparative study was conducted to determine the effect of isoniazid prophylaxis on the incidence of active tuberculosis among Thai HIV-infected patients for 1 year . Among those 36 HIV-infected patients without prophylaxis, the incidence of active tuberculosis was 2.7 per cent while in 10 HIV-infected patients with isoniazid prophylaxis, there was no incidence of active tuberculosis during the first yearPIP: In Thailand during 1994-1995, 46 HIV-seropositive asymptomatic patients were followed-up monthly for 1 year to evaluate the prophylactic effect of isoniazid against tuberculosis among these patients . 36 patients did not receive isoniazid; the remaining 10 patients received 300 mg isoniazid daily for 1 year . The 2 groups were matched for age and sex . Three controls and 1 case dropped out of the study during the second half . Only 1 (2.7%) of the controls developed active tuberculosis . Active tuberculosis in this case developed on the fifth month of follow-up . This patient responded well to anti-tuberculosis drugs (300 mg isoniazid, 600 or 450 mg rifampicin depending on weight, 20-30 mg/kg pyrazinamide daily, and 1 g streptomycin daily for 2 weeks and 15 mg/kg thereafter) . No cases developed active tuberculosis . Despite study weaknesses (e.g., low sample size), prophylactic isoniazid is recommended for HIV-positive asymptomatic patients . Rinsho Byori, 1996 May, 44(5), 456 - 64 Multicenter evaluation of a colorimetric microplate antimycobacterial susceptibility test: comparative study with the NCCLS M24-P; Yamane N et al.; A colorimetric test method using the microplate culture technique for the determination of susceptibility of Mycobacterium tuberculosis against antimycobacterial agents was developed and evaluated by the multicenter study . The test method utilizes an oxidation-reduction dye, 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride (STC), as an indicator of mycobacterial growth . When compared to the presently available test method, some modifications were also included; lower inoculum density (10-fold dilution), inclusion of an inoculum diluted 1:100 as a growth control, and the preparation of inoculum preincubated in Middlebrook 7H9 broth and spectrophotometrically adjusted to McFarland #1 turbidity . The test method evaluated was highly precise and reliable to detect antimycobacterial resistances when the ATCC reference strains were tested . Also, the interpretations of the test result were highly comparable to those determined by the method of NCCLS M24-P, the % agreements ranging from 76.1% (ethambutol) to 91.3% (streptomycin) . The test results were also comparable to those determined by Ogawa media; > 90% agreed with susceptible, intermediate, or resistant . The appearance of mycobacterial colonies on the test media was easily read, and the test results were more comparable to those of NCCLS M24-P . With these results, it can be concluded that the colorimetric microplate susceptibility test method described will be more suitable for clinical mycobacteriology laboratories. Infect Immun, 1996 May, 64(5), 1569 - 76 Activation of Shiga-like toxins by mouse and human intestinal mucus correlates with virulence of enterohemorrhagic Escherichia coli O91:H21 isolates in orally infected, streptomycin-treated mice; Melton-Celsa AR et al.; The enterohemorrhagic Escherichia coli (EHEC) O91:H21 isolates B2F1 and H414-36/89 are virulent in an orally infected streptomycin-treated mouse model . Previous studies demonstrated that B2F1 and H414-36/89 grow to high levels in mucus isolated from mouse small intestine and colon and that growth in small-intestine mucus is related to virulence . We measured the levels of Shiga-like toxins (SLTs) SLT-IIvha and SLT-IIvhb produced by B2F1 after growth in Luria-Bertani (LB) broth supplemented with mouse intestinal mucus by assaying the cytotoxicity of culture supernatants on Vero cells . Culture supernatants from B2F1 grown in mouse intestinal mucus, but not EHEC strains that produce SLT-II or SLT-IIc, were approximately 35- to 350-fold more toxic for Vero cells than supernatants from B2F1 grown in LB broth . This increased toxicity was not reflected by a concomitant increase in SLT antigen content . Furthermore, when culture supernatants from B2F1 or K-12 strains carrying plasmids encoding SLTs cloned from H414-36/89 or purified SLT-IIvhb from B2F1 were incubated with mouse intestinal mucus, the samples exhibited greater cytotoxicity than when they were incubated with N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES) buffer alone . These toxin preparations also showed increased cytotoxicity after incubation with human colonic mucus . In contrast, culture supernatants from LB-grown EHEC isolates that produced SLT-I, SLT-II, SLT-IIc or SLT-IIe did not show increased cytotoxicity after incubation with mouse or human intestinal mucus . The A subunits of purified SLT-II and SLT-IIvhb that had been treated with mouse intestinal mucus or trypsin were cleaved to A1 fragments by the mucus, but trypsin-mediated cleavage, unlike treatment with mouse intestinal mucus, did not result in increased Vero cell cytotoxicity activity . This finding implies that the increased cytotoxicity of SLT-IIvhb detected after incubation with mucus is probably not due to cleavage of the A subunit into the A1 and A2 fragments . Taken together, these results indicate that mouse or human intestinal mucus directly activates SLT-II-related toxins from B2F1 and H414-36/89 and suggest that toxin activation may explain the low 50% lethal doses of B2F1 and H414-36/89 in streptomycin-treated mice. Ear Nose Throat J, 1996 Apr, 75(4), 239 - 43 Very high-dose streptomycin labyrinthectomy; Sataloff RT et al.; Medical labyrinthectomy by systemic administration of streptomycin has proven safe and effective for treatment of selected patients with intractable vertigo . In most patients, 40 grams or less of streptomycin sulfate are required . However, otolaryngologists should be aware that much higher doses can be used safely in selected patients; and a small number of patients may be resistant to streptomycin toxicity even in doses over 100 grams. Otolaryngol Clin North Am, 1996 Apr, 29(2), 353 - 8 Dexamethasone perfusion of the labyrinth plus intravenous dexamethasone for Ménière's disease; Shea JJ Jr et al.; Recent clinical and laboratory evidence indicates that Meniere's disease is an immune-mediated disease . Dexamethasone perfusion of the inner ear through the round window plus intravenous dexamethasone often will stop the dizzy spells, reduce the fullness and low-frequency tinnitus, and sometimes improve the hearing in patients with Meniere's disease . The dexamethasone must act mostly on the endolymphatic sac and, to a lesser extent, on the stria vascularis and spiral ligament, the known targets of immune response in the inner ear, to reduce the endolymphatic hydrops and restore the fluid dynamics of the endolymph . Despite the good results with streptomycin perfusion, the number of patients with further hearing loss is large, so dexamethasone perfusion with intravenous dexamethasone should be tried first . The initial response to dexamethasone perfusion plus intravenous dexamethasone has been very good, with very little risk of further hearing loss, and it holds great promise for the future. Antimicrob Agents Chemother, 1996 Apr, 40(4), 1024 - 6 Characterization of rpsL and rrs mutations in streptomycin-resistant Mycobacterium tuberculosis isolates from diverse geographic localities; Sreevatsan S et al.; Two genes (rpsL and rrs) with mutations associated with streptomycin resistance in Mycobacterium tuberculosis were characterized in 78 streptomycin-resistant and 61 streptomycin-susceptible isolates recovered from patients living in the United States, South America, Europe, Africa, and Asia . Fifty-four percent of the 78 resistant organisms had missense mutations in codon 43 of rpsL resulting in a K-43-->R substitution . Mutations in codon 88 of rpsL were also identified in four Asian isolates. Arch Biochem Biophys, 1996 Apr 1, 328(1), 9 - 16 Rate of translation of natural mRNAs in an optimized in vitro system; Pavlov MY et al.; We report results on in vitro translation of an mRNA coding for elongation factor TuB which was in vitro transcribed from the tufB gene from Escherichia coli . Translation occurs at a rate of about 10 codons per second, which is close to the in vivo rate . Protein elongation obeys Michaelis-Menten kinetics with respect to the concentrations of the elongation factors EF-Tu and EF-G in the translation system . The measured K(m) values for EF-Tu and EF-G are 10 and 0.25 microM, respectively . The obtained k(cat) and K(m) values were used to estimate the average k(cat)/K(m) of about 24 x 10(6) s-1 M-1 for the interaction of individual EF-Tu*GTP*aa-tRNA complexes with ribosomes . The estimated k(cat)/K(m) value for EF-G is 36 x 10(6) s-1 M-1 . We have also studied translation with a "hyperaccurate" ribosome variant that is pseudodependent on streptomycin (SmP) . We have found that SmP ribosomes translate the TuB mRNA significantly slower than wild-type ribosomes do . This is mainly due to a threefold lower k(cat)/K(m) for the interaction of EF-Tu*GTP*aa-tRNA complexes with SmP ribosomes. Lancet, 1996 Mar 23, 347(9004), 807 - 9 Tuberculosis programme changes and treatment outcomes in patients with smear-positive pulmonary tuberculosis in Blantyre, Malawi; Harries AD et al.; PIP: The rates of tuberculosis (TB) notifications and treatment outcomes in Queen Elizabeth Central Hospital in Blantyre, Malawi, and the measures introduced to improve treatment were assessed by analyzing patient records and treatment outcomes . From 1989 to 1991, the number of TB cases registered increased by 58% . From 1991 to 1993, the number of cases per year did not change . However, from 1991 onward the number of TB patients within Blantyre district continued to rise, and treatment outcomes in new smear-positive TB patients deteriorated substantially . In 1991 the cure rate for the last two quarters was 32% and the default rate was more than 40% . The increase in TB patients between 1989 and 1991 strained TB services and contributed to the deterioration in treatment outcomes . In 1991 measures were taken to counter the worsening trend with a focus on staffing, staff activities, treatment regimens, and sputum-collection procedures . The arrival of a physician in July 1991 and another in October 1992 led to improved diagnosis and more extensive health education of patients . In May 1993 a health surveillance assistant was hired for health education and supervision of patients . In July 1993 a district health TB officer was appointed to supervise TB activities in health centers . Also, monthly TB meetings were started for all health staff . At the end of 1993 the number of nurses were also increased . In October 1991 an outpatient regimen for smear-negative pulmonary TB and moderate extrapulmonary TB replaced the standard regimen . This new regimen consisted of 2 months of rifampicin, isoniazid, and pyrazinamide each given three times per week, followed by 2 months of daily isoniazid and ethambutol, and then 4 months of isoniazid . Then, in March 1992, another regimen was introduced: 1 month of daily streptomycin, rifampicin, isoniazid, and pyrazinamide followed by 1 month of these drugs three times per week, and then 6 months of maintenance treatment with isoniazid and thiacetazone . Schweiz Med Wochenschr, 1996 Mar 9, 126(10), 392 - 7 {Fulminant, rapidly reversible hepatitis and life-threatening anaphylaxis following rifampicin in an HIV-positive female patient with latent adrenal cortex insufficiency}; Canova CR et al.; We report the case of a 28-year-old-prostitute from Thailand with HIV infection stage B2 associated with retroperitoneal lymph node tuberculosis . 6 days after the beginning of anti-tuberculous therapy (isoniazid, rifampicin, pyrazinamid and ethambutol) the temperature rose to 40.5 degrees C, diarrhea, vomiting, and tachycardia developed and systolic blood pressure fell to 80 mm Hg . Liver function tests revealed acute hepatic failure (ALT 800 IU/l rising to 1500; serum bilirubin 89 mumol/l rising to 238.0; alkaline phosphatase 199 IU/l; glucose 1.8 mmol/l; prothrombin time 20%) . Isoniazid, rifampicin, and pyrazinamid were replaced by streptomycin and PAS . A few days after withdrawal the liver profile returned to normal . Hours after the reintroduction of rifampicin total body erythema, pruritus, vomiting and severe hypotension developed, requiring saline methylprednisolone and epinephrine administration . The next reexposure to intravenous rifampicin produced a rash and was rapidly discontinued . Liver function tests remained normal . Later mild adverse reactions to streptomycin and pyrazinamid occurred, two drugs which had been well tolerated before . Subsequently the diagnosis of adrenal insufficiency was established . After initiation of steroid replacement (50 mg prednisolone) the antituberculous therapy with isoniazid, pyrazinamid and ethambutol was well tolerated . We conclude that the shock in this HIV-infected patient was either due to severe anaphylaxis to rifampicin or acute adrenal insufficiency ensuing on this drug . The reversible fulminant acute hepatic failure represents either an adverse effect of antituberculous drugs, especially hepatotoxic interactions of drug combinations, or an ischemic liver injury during hypotension caused by anaphylaxis . The case illustrates the complex nature of side effects of antituberculous drugs in HIV patients and their aggravation by adrenal insufficiency. Biochem Mol Biol Int, 1996 Mar, 38(3), 493 - 500 Purification and partial characterization of Ca(2+)-dependent ribonucleotide reductase from Streptomyces aureofaciens; Racay P et al.; Ribonucleotide reductase (EC 1 . 17 . 4 . 1.) is an essential enzyme providing 2'-deoxy-ribonucleotides for DNA replication . Ribonucleotide reductase from Streptomyces aureofaciens was purified 3365-fold with a yield of 6.5% . After homogenization of cells by ultrasonic homogenizer and DNA removing by 7% (w/v) solution of streptomycin sulphate, the sample was chromatographed on a DEAE-Sepharose CL 6 B, Phenyl-Sepharose CL 4 B, Heparin-Sepharose CL 6 B and a Sephacryl S-200 . The specific activity of the purified protein was 1740 pmol per s per mg . Sephacryl S-200 chromatography and sodium dodecyl sulphate-polyacrylamide gel electrophoresis revealed that in the presence of calcium ions the enzyme appears to be a dimer with an apparent molecular weight of 125.9 kDa . In the absence of calcium dimer dissociates into a monomer with the apparent molecular weight of 64.3 kDa . On the basis of these results, we suggest that calcium plays a role in the formation of the dimer, which is the biologically active form of ribonucleotide reductase. Nihon Kyobu Shikkan Gakkai Zasshi, 1996 Mar, 34(3), 374 - 9 {Pulmonary and endobronchial tuberculosis with subclavian artery-pulmonary artery shunts}; Ando M et al.; A 77-year-old woman with a productive cough and fever was admitted to the hospital . Pulmonary and endobronchial tuberculosis, pneumonia of the left upper lobe, and stenosis of the left main bronchus were diagnosed . She was given the antimycobacterial drugs isoniazid, rifampin, and streptomycin, and her condition improved . Two months later, bronchoscopy revealed semilunar-shaped stenosis of the left main bronchus, and auscultation revealed wheezing in the middle-end expiratory phase . A continuous flow murmur (Levine III) was also heard at the left anterior chest wall . Cardiac catheterization with subclavian arteriography revealed two left subclavian-pulmonary shunts . In a case of systemic-pulmonary shunt such as this, the bronchial stenosis could be surgically repaired, but the result would be an increase in dead space . If left untreated, the pulmonary hypertension would progress and symptoms of pulmonary disease would become more severe . Subclavian-pulmonary artery shunt is a very rare complication of pulmonary tuberculosis . Surgical treatment should consist of open bronchoplasty along with lobectomy and removal of the shunt, rather than embolization of the shunt and endoscopic bronchoplasty. J Commun Dis, 1996 Mar, 28(1), 15 - 9 Initial and acquired drug resistance of Mycobacterium tuberculosis in east Delhi; Mahajan M et al.; One hundred and fifty six strains of Mycobacterium tuberculosis, isolated from cases of pulmonary tuberculosis were subjected to sensitivity test to detect initial and acquired drug resistance to Streptomycin, isoniazid, Rifampicin, Ethambutol and Pyrazinamide . Initial and acquired drug resistance was observed to one or more drugs in 16% and 24.4% of the patients respectively . Strains resistant to Rifampicin and Ethambutol were resistant to Isoniazid also . Drug resistance was unrelated to age and sex of the patients. Arch Bronconeumol, 1996 Mar, 32(3), 118 - 21 {Resistance of Mycobacterium tuberculosis in the province of Castellón}; Moreno R et al.; We conduced a cross-sectional study to determine the prevalence of resistant mycobacteria in our setting . All patients in whom M . tuberculosis had been isolated in cultures of clinical samples (119) between January 1992 and December 1993 took part in the study . Canetti's method of percentages was used for the study of sensitivity to the following drugs: isocyanide, rifampicin, streptomycin, ethambutol and para-aminosalicylic acid . Overall resistance of M . tuberculosis was 9.24% . Specifically, we found resistance to isocyanide in 5.9%, to streptomycin in 4.20%, to rifampicin in 5.04% and to ethambutol in 1.68% . Resistance was primary in 7% and secondary in 21.05%; 2% showed primary resistance to isocyanide, 1% to isocyanide and rifampicin, 2% to streptomycin, 1% to ethambutol and 1% to streptomycin and rifampicin . These resistance indices are in keeping with those published for other areas of Spain. EMBO J, 1996 Mar 1, 15(5), 1149 - 54 Dissociation rates of peptidyl-tRNA from the P-site of E.coli ribosomes; Karimi R et al.; We studied the dissociation rates of peptidyl-tRNA from the P-site of poly(U)-programmed wild-type Escherichia coli ribosomes, hyperaccurate variants altered in S12 (SmD, SmP) and error-prone variants (Ram) altered in S4 or S5 . The experiments were carried out in the presence and absence of streptomycin, and the effects of neomycin were tested in the wild-type ribosomes . Binding of peptidyl-tRNA to the P-site of wild-type ribosomes is much stronger than to their A-site . Addition of streptomycin dramatically reduces its affinity for the P-site . The S12 alternations make the P-site binding of peptidyl-tRNA much tighter, and the S4, S5 alterations make it weaker than in the case of the wild-type . We find that when binding of peptidyl-tRNA to the A-site is weak, then the affinity for the P-site is stronger, and vice versa . From these results, we formulate a hypothesis for the actions of streptomycin and neomycin based on deformations of the 16S rRNA tertiary structure . The results are also used to interpret some in vivo experiments on translational processivity. Biochem Pharmacol, 1996 Feb 23, 51(4), 437 - 45 Purification and characterization of an Ah receptor binding factor in chromatin; Dunn RT 2nd et al.; Dioxin induces biological responses through interaction with a specific intracellular receptor, the Ah receptor, and the subsequent interaction of the Ah receptor with chromatin . We previously reported the binding of the Ah receptor, partially purified form rabbit liver, to receptor binding factors (termed AhRBFs) in chromatin . Rabbit liver chromatin proteins (CP) were isolated by absorption of chromatin to hydroxylapatite followed by sequential extraction with 3 M NaCl and 1-8 M guanidine hydrochloride (GdnHCl) . In the present study, we continued the purification of the CP5 fraction, which exhibited AhRBF activity . The proteins in CP5 were separated by CL-Sepharose 6B column chromatography resolving lower molecular weight fractions . To assay for receptor binding, a portion of each Cl-Sepharose 6B fraction was reconstituted to rabbit double-stranded DNA (dsDNA) using a reverse gradient dialysis of 7.5 to 0.0 M GdnHCl . These reconstituted chromatins were then examined for binding to {3H}-2,3,7,8-tetrachlorodibenzo-p-dioxin ({3H}TCDD)-receptor complexes by the streptomycin filter binding assay . Two protein fractions with a molecular weight in the range of 10,000-14,000 demonstrated high affinity binding to the Ah receptor . The binding of AhRBFs reconstituted to dsDNA was shown, by competition experiments with Ah receptor bound by unlabeled TCDD (TCDD-R), to be > 90% specific for {3H}TCDD-R . Further purification was achieved by preparative ADS-PAGE, and AhRBF activity was attributed to two fractions with molecular weights between 12,000 and 10,000 . A kDa protein with AhRBF activity was found to have an isoelectric point (pI) of > or = 10 . The 12 kDa AhRBF was sequenced by Edman degradation after cyanogen bromide cleavage and identified as histone H4 . Although histone H4 has been postulated to interact with transcription factors in a variety of systems, this is the first report of a specific interaction of AhR with histone H4. Gene, 1996 Feb 22, 169(1), 91 - 5 The aerial mycelium-defective phenotype of Streptomyces griseus resulting from A-factor deficiency is suppressed by a Ser/Thr kinase of S . coelicolor A3(2); Ueda K et al.; A-factor (2-isocapryloyl-3R-hydroxymethyl-gamma-butyrolactone) is essential for aerial mycelium formation and streptomycin (Sm) production in Streptomyces griseus . A protein Ser/Thr kinase (AfsK), the product of the Streptomyces coelicolor A3(2) afsK gene, controlling secondary metabolism in this strain, reversed the aerial mycelium-negative phenotype of an A-factor-deficient mutant strain, S . griseus HH1, and induced sporulation without affecting A-factor productivity or Sm production . A mutant AfsK protein lacking kinase activity failed to induce aerial mycelium formation which indicates the importance of the kinase activity for suppression in S . griseus . These data suggest that a Ser/Thr kinase functionally similar to S . coelicolor A3(2) AfsK plays a regulatory role in aerial mycelium formation in S . griseus, either as a member in the A-factor regulatory network or independently of this network. Lancet, 1996 Feb 10, 347(8998), 358 - 62 Results of directly observed short-course chemotherapy in 112,842 Chinese patients with smear-positive tuberculosis . China Tuberculosis Control Collaboration; Occurrence of silent RNA editing in chloroplasts: its species specificity and the influence of environmental and developmental conditions; Center for Gene Research, Nagoya University, JapanWe have identified three new C-to-U RNA editing sites, one in atpF and two in atpA transcripts from tobacco chloroplasts . Two of them lead to amino acid substitutions to restore the conserved amino acid found in the corresponding genes of other plants . However, one editing site in the atpA transcript was found to take place partially at the third base of a serine codon (CUC_ to CUU_), thus not leading to an amino acid substitution . This is the first report of silent editing in chloroplasts . The extent of silent editing depends on plastid stage and light conditions, while editing as another site (found 4 nt upstream from the silent editing site) takes place constitutively even in non-photosynthetic cultured cells and bleached white seedlings grown in the presence of spectinomycin and streptomycin . In pea and spinach, despite a conservation in sequence, no editing at the site corresponding to the silent site in tobacco was found . This observation suggests that the silent editing detected in this study is species-specific. S Afr J Commun Disord, 1996, 43, 3 - 6 Ototoxicity of aminoglycoside drugs in tuberculosis treatment; Voogt GR et al.; The possible ototoxic effect of kanamycin, streptomycin and a standard anti-TB drug combination, used in the treatment of 92 TB patients (7-71 years old), was examined by measuring the highest audible electric bone conduction frequency before and after treatment, using an Audimax 500 audiometer . At the so-called "safe" levels of drug administration it was found that kanamycin was markedly ototoxic, streptomycin very slightly ototoxic and the standard anti-TB drug combination had practically no ototoxic effect . Furthermore, it was found that none of these drugs were gender specific . Lastly, the possible effects of ageing on highest audible bone conduction frequency is discussed. Biochimie, 1996, 78(11-12), 959 - 69 Dual functions of ribosome recycling factor in protein biosynthesis: disassembling the termination complex and preventing translational errors; Janosi L et al.; We summarize in this communication the data supporting the two functions of ribosome recycling factor (RRF, originally called ribosome releasing factor) . The first described role involves the disassembly of the termination complex which consists of mRNA, tRNA and the ribosome bound to the mRNA at the termination codon . This process is catalyzed by two factors, elongation factor G (EF-G) and RRF . RRF stimulated protein synthesis as much as eight-fold in the in vitro lysozyme synthesis system, when ribosomes were limiting . In the absence of RRF, ribosomes remain mRNA-bound at the termination codon and translate downstream codons . In the in vitro system, the site of reinitiation is the triplet codon 3' to the termination codon . RRF is an essential protein for bacterial life . Temperature sensitive (ts) RRF mutants were isolated and in vivo translational reinitiation due to inactivation of ts RRF was demonstrated using the beta-galactosidase reporter gene placed downstream from the termination codon . A second function of RRF involves preventing errors in translation . In polyphenylalanine synthesis programmed by polyuridylic acid, misincorporation of isoleucine, leucine or a mixture of amino acids was stimulated upto 17-fold when RRF was omitted from the in vitro system . RRF did not influence the large error (10-fold increase) induced by streptomycin . This means that RRF participates not only in the disassembly of the termination complex but also in peptide elongation . Extending this concept and its conventional role for releasing ribosomes from mRNA, involvement of RRF in the reinitiation in the 3A' system (a construct using S aureus protein A, a collaborative work with Dr Isaksson), in programmed frame shifting, in trans-translation with 10Sa RNA (collaborative work with Dr Muto), and in the reinitiation downstream from the ORF A of the IS 3 (insertion sequence of a transposon, collaborative work with Dr Sekine) are discussed on the basis of preliminary data to be published elsewhere . Finally, we review the known RRF sequences from various organisms including eukaryotes and discuss the possible mechanism for disassembly of the eukaryotic termination complex. Probl Tuberk, 1996, (6), 52 - 4 {Dynamics of isolation of mycobacterium tuberculosis during 2-stage standard chemotherapy}; Khomenko AG et al.; Two-stage standard chemotherapy was performed in 149 newly detected patients with pulmonary tuberculosis, by isolating Mycobacteria . Within the first 2 months, the patients received 4 drugs: isoniazid, rifampicin, pyrazinamide, streptomycin or ethambutol . Treatment with two agents (isoniazid and rifampicin) was continued for 4 months . Mycobacterial isolation was stopped in 104 patients after 2 months of treatment, in other 26 after 3 months, which amounts to 80.2% . Higher therapeutical results were observed in patients who had isolated Mycobacteria resistant to 1 and even 2 drugs. Arch Virol, 1996, 141(8), 1453 - 62 Evidence that neomycin inhibits human cytomegalovirus infection of fibroblasts; Lobert PE et al.; The effect of phosphoinositide-binding aminoglycosides, such as neomycin, gentamicin and streptomycin, on human cytomegalovirus (HCMV) infection of human fibroblasts MRC-5 was studied . The inhibition of HCMV infection was obtained with all of these molecules but neomycin was more effective than the others . We showed that the inoculation of the cells with cell-free viral suspension in presence of neomycin concentrations above 5 mM at 37 degrees C, inhibited more than 98% the HCMV infection . However, the preincubation of the fibroblasts with neomycin at 4 degrees C, before the removal of the drug and the inoculation of the cells, induced only a 30% decrease in the number of infected cells . Addition of neomycin after the HCMV-binding at 4 degrees C or the infection of the cells was less efficient to inhibit HCMV infection than the standard incubation of neomycin during inoculation of the fibroblasts . Indeed, 1 hour after the inoculation of the cells at 37 degrees C, neomycin still inhibited HCMV infection, but 4 hours after the inoculation, this drug had no effect on HCMV infection . Our findings demonstrated that neomycin must be present at the time of infection in order to exert a full inhibiting effect . The effect of neomycin on the HCMV infection was almost immediate upon the addition of the drug (binding and/or internalization) and after the virus internalization (inhibition of immediate-early events) . We suggest that neomycin and other aminoglycoside antibiotics may interact with HCMV glycoproteins for binding to similar structural features of cell surface heparan sulfate proteoglycans and may inhibit HCMV infection in fibroblasts by disrupting phosphoinositide-mediated events in the cells. Pneumologie, 1996 Jan, 50(1), 28 - 35 {Incidence of resistance and risk factors for resistance in Mycobacterium tuberculosis . A retrospective study of 1,055 patients of a specialty hospital 1984 to 1993}; Borchardt J et al.; For the past decade, there have been no data on the time course of drug-resistant tuberculosis and on risk factors for drug resistance in former West Germany . We reviewed the medical records of all patients with positive cultures for Mycobacterium tuberculosis from 1984 until 1993 in a hospital near Hamburg . Drug-susceptibility testing was performed for isoniazid, rifampicin, ethambutol, and streptomycin, using the modified proportion method . Of 1,055 patient, 9.6% had isolates resistant to one or more drugs . Of the isolates, 5.8% showed resistance to isoniazid or rifampicin and 1.8% to both isoniazid and rifampicin . There was no significant change of the resistance rate during the study period . Twenty six percent of 89 patients from South America, Africa or Asia had isolates resistant to one or more drugs, compared with 7.6% of 799 patients born in Germany (odds ratio (OR) 4.2; 95% confidence interval (95% CI) 2.5-7.3) . Among patients born in Germany, 32% of 101 patients with a history of prior antituberculosis drug therapy had resistant organisms, versus 4.2% of 698 patients without prior therapy (OR 10.7; 95% CI 6.1-18.7) . Resistance orates for 35 patients, who had been treated within the last 5 yrs, and for 65 patients, who had been treated more than 5 yrs ago, were 57 and 17%, respectively (OR 6.6; 95% CI 2.9-16.6) . Our results suggest that there is no increase in the proportion of drug-resistant tuberculosis in our hospital, and that patients with a recent history of antituberculosis drug therapy and patients from South America, Africa, or Asia are at high risk for drug resistance. Eur J Pediatr, 1996 Jan, 155(1), 1 - 6 Childhood brucellosis in north-western Greece: a retrospective analysis; Galanakis E et al.; Fifty-two cases of childhood brucellosis which occurred in north-western Greece during the 15-year period 1979-1993, are reviewed . It is believed that they represent very closely the total incidence of the disease in the region which has a population of 100,000 children aged 0-14 years old . Brucellosis-affected children were almost exclusively from goat- or shepherd families and of both sexes and all age groups . A broad spectrum of clinical manifestations ranging from malaise only to brain abscess was observed . Fever and arthralgia were the most common manifestations followed by malaise, myalgia, sweating, rash, cough, and gastro-intestinal, cardiac and CNS involvement . Splenomegaly was found more often than hepatomegaly and lymphadenopathy . Laboratory findings included anaemia, leukopenia, neutropenia, lymphocytopenia, monocytosis, eosinophilia, thrombocytopenia and pancytopenia . Leukocytosis and lymphocytosis were extremely rare and ESR and serum C-reactive protein levels were mildly elevated . All patients had positive Rose Bengal slide agglutination tests and standard tube agglutination titres of 1:160 or more . When performed, blood culture was often diagnostic . The children were treated with streptomycin for 2 weeks plus either tetracyclines or trimethoprim-sulphamethoxazole for 3 weeks . Treatment was well tolerated . Relapse was observed in one case . CONCLUSION: Brucellosis nowadays affects children in an occupational pattern . As symptoms, signs and first-line laboratory findings are not characteristic, agglutination tests and blood culture should be performed in any child with prolonged fever . Treatment is effective, but prevention of the disease by animal testing and education of high risk families is indicated. Yi Chuan Xue Bao, 1996, 23(2), 158 - 62 {Molecular mechanism of suppressing lambda N gene's expression in E . coli ribosomal protein S12 streptomycin-dependent mutant}; Jiang X et al.; Using the polymerase chain reaction (PCR) method, the rpsLd gene was amplified and cloned, which encodes the streptomycin-dependent (Smd) mutant of ribosomal protein S12 in E.coli T83 . The result of DNA sequencing showed an AAA to CAA mutation at codon 42, leading to the substitution of glutamine (Gln, Q) for lysine (Lys, K) . According to the principle of Garnier, we predicted that there might be alterations in the secondary structural propensity of protein S12 due to the mutation . The outcome indicated that the beta-turn propensity at position 42 and its nearby region was increased evidently and the relative position of relevant subdomains were changed . As a result, the special conformation of the whole protein S12 was influenced . In view of that ribosomal proteins and ribosomal RNAs (rRNA) mutually adapted in structures and functions, the probable molecular mechanism . That how protein S12 Smd mutant in E.coli T83 suppressed lambda N gene's expression is discussed. Am J Otol, 1996 Jan, 17(1), 15 - 8 Cochlear fistula in chronic otitis media with cholesteatoma; Chao YH et al.; Labyrinthine fistula in chronic otitis media with cholesteatoma most commonly involves the horizontal semicircular canal . We report three cases of cochlear fistula in chronic otitis media with cholesteatoma . All of them had a long history of otorrhea . One patient had total hearing loss of the affected side . The other two patients had conductive hearing loss . Radical mastoidectomy had been done in all cases . Cholesteatoma in the tympanic cavity destroyed the basal turn of the cochlea . These fistulas were sealed with muscle or Gelfoam with streptomycin . We found no fistula in the semicircular canal in any of the three cases . We report three cases of cochlear fistula in chronic otitis media with cholesteatoma, and review the literature. Planta, 1996, 199(2), 193 - 201 Integration of foreign sequences into the tobacco plastome via polyethylene glycol-mediated protoplast transformation; Koop HU et al.; A new vector, pFaadAII, for transformation of plastids of Nicotiana tabacum L . has been developed . It harbours a chimeric gene consisting of the aadA coding region from Escherichia coli, the 16S rDNA promoter from tobacco combined with a synthetic ribosome-binding site, a 500-bp fragment containing the 3' untranslated transcript region (UTR) of the Chlamydomonas rbcL gene and 3.75-kb (5') and 0.95-kb (3') tobacco plastome sequences allowing for targeting the foreign sequences to the intergenic region between the rpl32 and trnL genes of the tobacco plastome . The vector thus targets foreign sequences to the small single-copy region of the plastome, which has so far not been modified by transformation . Leaf protoplasts of Nicotiana tabacum L . were treated with polyethylene glycol (PEG) in the presence of the vector . The protocol for PEG treatment aiming at plastome transformation was optimized . Cell lines were cultured in the presence of spectinomycin and streptomycin using a novel and efficient protoplast culture and selection system . Regenerants were characterized by polymerase chain reaction (PCR) analysis, Southern hybridization and reciprocal crossing . The transformation procedure is described in detail and parameters influencing its efficiency are presented . Special effort is placed on analyzing suitable selection conditions . Only a proportion of the cell lines with a resistant phenotype could be confirmed by molecular analysis and/or reciprocal crossings to represent plastome transformants . Integration of the plastome specific aadA cassette into the nuclear genome accounted for a fraction of the resistant cell lines . Still, as many as 20-40 plastome transformants can be expected from the treatment of 10(6) protoplasts . Therefore, the improved protocol for PEG-mediated plastome transformation in combination with the new aadA-vector supplies a simple, reproducible and cost-efficient alternative to the biolistic procedure. Can J Microbiol, 1996 Jan, 42(1), 12 - 8 Characterization of the drug resistance plasmid R2418: restriction map and role of insertion and deletion in its evolution; Guessouss M et al.; Escherichia coli 2418 strain is resistant to beta-lactam antibiotics (ampicillin, carbenicillin, and cephalothin), streptomycin, tetracycline, kanamycin, and chloramphenicol . This strain contains at least two conjugative plasmids (R2418 and R2418S) encoding resistance to beta lactam antibiotics and resistance to both beta-lactam antibiotics and streptomycin, respectively . Restriction endonuclease mapping of plasmid DNAs indicates that the plasmid R2418S has evolved from R2418 DNA by the insertion of 2.5-kb DNA between BamHI and PvuII sites, and deletion of 0.5-kb DNA within the EcoRI-EcoRV region . The 2.5-kb DNA insert is responsible for streptomycin resistance . This evolution is also associated with a reduction in the efficiency of conjugal transfer for the plasmid R2418S . The conjugal transfer of streptomycin resistance occurs only through the coresidence of the conjugative plasmid R2418 or R2418S in the donor cell . In accordance with the hypothesis that the Smr determinant is due to a putative transposon, plasmid-free transconjugants resistant to streptomycin only were isolated . Southern blot analysis of HindIII chromosomal digests extracted from these transconjugants shows that the Smr determinant is inserted into different sites in chromosomal DNA. J Diarrhoeal Dis Res, 1995 Dec, 13(4), 238 - 41 Treatment of diarrhoea in infants by medical doctors in Balochistan, Pakistan; Kasi M et al.; Diarrhoea is an important public health problem in Balochistan, the westernmost province of Pakistan . Although the use of oral rehydration solutions (ORS) has been widely promoted, no studies have been reported on the actual uses of ORS in treating infant diarrhoea by the medical doctors in this region . The medical practices of 30 doctors in Balochistan were surveyed . The surveyors posed as the mothers of infants with diarrhoea . The questions asked by the doctors, the physical examinations performed, and the treatments prescribed were noted . The histories and physical examinations were incomplete, as performed by most practitioners . In addition, 80% of the doctors prescribed drugs, usually kaolin preparations to treat diarrhoea . However, 18 of the 30 (60%) practitioners also prescribed ORS for treating diarrhoea and most of them gave some recommendations about ORS use . It is concluded that many medical practitioners have incorporated ORS treatment into their practices . Ongoing educational programmes and refresher courses would likely improve the use of ORS further in this regionPIP: Diarrhea is an important public health problem in Baluchistan, the western province of Pakistan . Although the use of oral rehydration solution (ORS) has been widely promoted, no studies have been reported on the actual uses of ORS in treating infant diarrhea by the doctors in this region . The medical practices of 30 doctors in the cities of Quetta and Loralai were surveyed . The surveyors posed as the mothers of three infants aged 6-8 months with diarrhea . The questions asked by the doctors, the physical examinations performed, and the treatment regimens prescribed were recorded . The outcome indicated that the case histories and physical examinations were incomplete as performed by most practitioners . None of the doctors asked about the frequency of stools, the time of the infant's recent urination, or the health of family members . Most physical examinations were severely deficient . Only two doctors performed adequate examinations (taking of temperature, pulse, respirations, skin pinch, evaluation of fontanelle and mucus membranes, and abdominal examination) . Two doctors ordered laboratory tests: both requested stool examination for parasites, ova, and leukocytes, dipstick urinalysis, and blood leucocyte count with differential . 24 doctors (80%) prescribed drugs, usually a kaolin preparation, to treat diarrhea, although only 11 of them gave instructions on how to take the medication . 46% of the doctors prescribed commercially prepared mixtures of kaolin and pectin or neomycin and pectin, while two doctors prescribed streptomycin . Other medication prescribed included: fosfomycin, amoxycillin, co-trimethoxazole, metronidazole, paracetamol, vitamin drops, and colic drops . However, 18 of the 30 (60%) practitioners also prescribed ORS for treating diarrhea, and most of them gave some recommendations about ORS use . 14 doctors (46%) recommended breast feeding to prevent diarrhea, while 6 (20%) commented on food hygiene, recommending hand washing and clean drinking water . Ongoing education programs and refresher courses would likely improve the use of ORS further in this region . Kansenshogaku Zasshi, 1995 Dec, 69(12), 1402 - 7 {A case of tuberculous meningitis followed by tuberculoma with pan-hypopituitarism}; Tomono N et al.; We reported a case who suffered from tuberculous meningitis at 10 months of age, and progressed to basal tuberculoma despite intensive drug therapy with isoniazid, rifampin, and streptomycin . Pan-hypopituitaliam due to basal tuberculoma was effectively replaced by the administration of anti-diuretic hormone (DDAVP) and levothyroxine sodium . Basal tuberculoma was finally removed by surgical operation . Histopathological examination of the tuberculoma revealed Mycobacterium tuberculosis and Langhans giant cells . During the 6 years after the operation, her growth rate was found to be retarded, and the administration of human growth hormone was started . Remarkable catch-up growth was demonstrated . We like to emphasize that infantile tuberculosis, mostly a result of intafamilial transmission, may manifest meningitis in the early phase of the disease, and it sometimes progresses to basal tuberculoma unresponsive to anti-mycobacterial drug therapy. Biochem Cell Biol, 1995 Nov-Dec, 73(11-12), 907 - 13 Pleiotropic effects of mutations at positions 13 and 914 in Escherichia coli 16S ribosomal RNA; Brakier-Gingras L et al.; Mutations at position 13 or 914 of Escherichia coli 16S ribosomal RNA exert pleiotropic effects on protein synthesis . They interfere with the binding of streptomycin, a translational miscoding drug, to the ribosomes . They increase translational fidelity, and this effect can be related to a perturbation of the higher order structure of the 530 stem-loop, a key region for tRNA selection . In contrast, the structure of the decoding center is not perturbed . The mutations also affect translational initiation, slowing down the formation of the 30S initiation complex . This effect can be related to a destabilization of the pseudoknot helix (17-19/916-918), at the convergence of the three major domains of 16S ribosomal RNA. Kekkaku, 1995 Nov, 70(11), 621 - 8 {A clinical study of non-tuberculous pulmonary mycobacteriosis}; Kurasawa T et al.; We studied the clinical features of sixty-one patients with non-tuberculous pulmonary mycobacteriosis (NTM), who were newly diagnosed at five national hospitals in Kinki area during 1993 . The study subjects were composed of 31 patients with M . avium complex (MAC) disease (20 males and 15 females), 21 with M . kansasii (MK) disease (19 males and 3 females), 2 males with M . szulgai (MS) disease and 2 females with M . chelonae (MC) disease . The rate of NTM to all culture proven mycobacteriosis was 20.2% and the rate of NTM to all culture proven, newly discovered mycobacteriosis was 18.2% and the rates were higher than Sakatani's report in 1994 (14% in 1991) . The ratio of MK to MAC was 22:35, and the ratio of MK was higher than the report of Sakatani . The mean age of patients with MK was 57.9 in male and 76.7 in female, that with MAC was 71.0 in male and 70.1 in female, that with MS was 57.0 in male and that 72.5 with MC in female . The proportion of elderly patients was higher than the former reports in Japan, especially in female with MK . The main lesions on chest X-ray was found in bilateral S1, 2(S1+2), particularly in the cases with cavitary lesions, but right middle lobe and left lingular lobe were mainly affected in some patients with MAC and S6 was often affected in elderly patients with MK . The chemotherapy with isoniazid, rifampicin, ethambutol and/or streptomycin (or kanamycin) w as highly effective in case with MK and MS disease, the efficacy was similar to pulmonary tuberculosis . Some patients with MAC were treated with combination of anti-tuberculosis drugs and new quinolons and/or clarythromycin, but the efficacy was not yet revealed. Pneumologie, 1995 Nov, 49(11), 590 - 5 {Monitoring ototoxic side effects in streptomycin therapy of tuberculosis patients with transitory evoked otoacoustic emissions TEOAE}; Furst G et al.; The transient stimulated otoacoustic emissions TEOAE's from 10 patients treated with Streptomycin for tuberculosis, were measured . The patients received a combination of four drugs consisting of isoniazid, rifampicin, pyrazinamid and streptomycin . All patients received a total of 30 grams of streptomycin during 30 days of treatment . Pure tone audiograms between 125 Hz and 8000 Hz were performed before, during and at the end of the treatment . The TEOAE's were measured in a soundproof cabin before during and after the streptomycin treatment . None of the patients experienced subjective dizziness, hearing loss or tinnitus . The pure tone audiograms showed no significant fluctuations . However, 14 of the 20 examined ears showed a significant decrease in the amplitudes of the TEOAE's . An observation of the TEOAE-amplitudes of each patient during the treatment allows an assessment of impending cochlear dysfunction before subjective hearing loss can be recognized. Neurologia, 1995 Nov, 10(9), 375 - 9 {Neurobrucellosis . A report of 13 cases}; Marzo Sola ME et al.; Thirteen patients with nervous system brucellosis are described . The clinical signs were heterogeneous: meningoencephalitis in 5 cases, meningoradiculitis in another 5, meningomyelitis with cranial neuropathy in 1 and of a vascular nature in 2 others . Neurologic signs appeared during the active phase in 5 patients and later in 8 . Diagnosis was based on clinical manifestations, serum and cerebrospinal fluid (CSF) serology, quantitative changes in CSF and favorable response to treatment . Therapy consisted of a combination of 2 or 3 of the following drugs: rifampin, doxycycline, streptomycin and trimethoprim sulfamethoxazole . In spite of favorable evolution, 5 patients suffered sequelae . We suggest that brucellosis be investigated when neurologic deficit ensues with no known etiology, especially in endemic countries. J Bacteriol, 1995 Nov, 177(22), 6401 - 10 Cloning and characterization of a gene involved in aerial mycelium formation in Streptomyces griseus; Kudo N et al.; A-factor (2-isocapryloyl-3R-hydroxymethyl-gamma-butyrolactone) is essentially required for aerial mycelium formation and streptomycin production in Streptomyces griseus . A DNA fragment which induced aerial mycelium formation and sporulation in an A-factor-deficient mutant strain, S . griseus HH1, was cloned from this strain on a high-copy-number plasmid . Subcloning and nucleotide sequencing revealed that one open reading frame with 218 amino acids, named AmfC, served as a multicopy suppressor of the aerial mycelium-defective phenotype of the A-factor-deficient strain . The amfC gene did not restore A-factor or streptomycin production, indicating that amfC is involved in aerial mycelium formation independently of secondary metabolic function . Disruption of the chromosomal amfC gene in the wild-type S . griseus strain caused a severe reduction in the abundance of spores but no effect on the shape or size of the spores . The infrequent sporulation of the amfC disruptant was reversed by introduction of amfC on a plasmid . The amfC-defective phenotype was also restored by the orf1590 gene but not by the amfR-amfA-amfB gene cluster . Nucleotide sequences homologous to the amfC gene were distributed in all of 12 Streptomyces species tested, including Streptomyces coelicolor A3(2) . The amfC homolog of S . coelicolor A3(2) was cloned and its nucleotide sequence was determined . The AmfC products of S . griseus and S . coelicolor A3(2) showed a 60% identity in their amino acid sequences . Introduction of the amfC gene of S . coelicolor A3(2) into strain HH1 induced aerial mycelium formation and sporulation, which suggests that both play the same functional role in morphogenesis in the strains. J Bacteriol, 1995 Nov, 177(21), 6083 - 92 Cloning and characterization of the A-factor receptor gene from Streptomyces griseus; Onaka H et al.; A-factor (2-isocapryloyl-3R-hydroxymethyl-gamma-butyrolactone) and its specific receptor protein control streptomycin production, streptomycin resistance, and aerial mycelium formation in Streptomyces griseus . The A-factor receptor protein (ArpA) was purified from a cell lysate of S . griseus IFO 13350 . The NH2-terminal amino acid sequences of ArpA and lysyl endopeptidase-generated fragments were determined for the purpose of preparing oligonucleotide primers for cloning arpA by the PCR method . The arpA gene cloned in this way directed the synthesis of a protein having A-factor-specific binding activity when expressed in Escherichia coli under the control of the T7 promoter . The arpA gene was thus concluded to encode a 276-amino-acid protein with a calculated molecular mass of 29.1 kDa, as determined by nucleotide sequencing . The A-factor-binding activity was observed with a homodimer of ArpA . The NH2-terminal portion of ArpA contained an alpha-helix-turn-alpha-helix DNA-binding motif that showed great similarity to those of many DNA-binding proteins, which suggests that it exerts its regulatory function for the various phenotypes by directly binding to a certain key gene(s) . Although a mutant strain deficient in both the ArpA protein and A-factor production overproduces streptomycin and forms aerial mycelium and spores earlier than the wild-type strain because of repressor-like behavior of ArpA, introduction of arpA into this mutant abolished simultaneously its streptomycin production and aerial mycelium formation . All of these data are consistent with the idea that ArpA acts as a repressor-type regulator for secondary metabolite formation and morphogenesis during the early growth phase and A-factor at a certain critical intracellular concentration releases the derepression, thus leading to the onset of secondary metabolism and aerial mycelium formation . The presence of ArpA-like proteins among Streptomyces spp., as revealed by PCR, together with the presence of A-factor-like compounds, suggests that a hormonal control similar to the A-factor system exists in many species of this genus. Gene, 1995 Oct 16, 164(1), 41 - 4 Detection of exonuclease activities in restriction endonuclease preparations using an enforcement plasmid for kanamycin-resistance selection; Hashimoto-Gotoh T et al.; A new enforcement (kyosei-) cloning plasmid vector, designated pKF4, was constructed which confers kanamycin resistance (KmR) and enforces streptomycin sensitivity (SmS) . Since it is important to employ restriction endonuclease (ENase) preparations free of exonuclease (Exo) activities for effective use of the kyosei-cloning procedure {Hashimoto-Gotoh et al., Gene 137 (1993) 211-216}, ENases such as HpaI and SmaI purchased from four different suppliers were examined for possible contamination by exonucleases using pKF4 . The plasmid DNA was digested with either ENase, ligated and transformed into Escherichia coli mutants, rpsL, supE, trpR . With pKF4 intact DNA (approx . 8 ng), 2.3 x 10(5) KmR transformant and four KmRSmR transformant colonies were obtained; the efficiency of transformation plating (ETP) of the intact DNA was approx . 2 x 10(-5) . On the other hand, the ETP values were significantly higher by one to three orders of magnitude when cut and re-joined DNAs were used under the same conditions in six out of eight ENase samples examined . The results indicate that even commercially supplied ENases, that should have passed their quality control test, could have been contaminated with Exo sufficient to interfere with effective use of the kyosei-cloning method . Therefore, it is advisable to examine ENase samples for possible contamination with Exo activities, in order to choose the right preparations for this method at the beginning of the experiments. Anal Biochem, 1995 Oct 10, 231(1), 230 - 6 Quantitative determination of effective nibbling activities contaminating restriction endonuclease preparations; Hashimoto-Gotoh T; A simple and sensitive procedure with which to detect residual exonucleolytic nibbling activities contaminating restriction endonuclease preparations is described . The procedure uses the kyosei-plasmid, pKF4, which confers kanamycin resistance and enforces streptomycin sensitivity encoded by the trp promoter/operator-driven rpsL+amber(PO(trp)-rpsL+4(am)) gene onto Escherichia coli streptomycin-resistant, amber-suppressive, trp repressor-negative strains such as TH5 . When TH5 cells transformed by pKF4 were selected on agar medium containing kanamycin plus streptomycin, the efficiency of transformation plating was substantially lower than that on agar containing kanamycin alone . However, when pKF4 DNA was digested by restriction enzymes that cut once per molecule within PO(trp)-rpsL+4(am) and relegated, the plating efficiency increased depending on the degree of contamination of exonucleolytic nibbling activities in the enzyme preparations, due to deletion mutation at the ligand junction . Plating efficiency was converted to inverted question markeffective nibbling activity inverted question mark corresponding to Bal31 nuclease-equivalent units . Using this procedure, effective nibbling activities were detected in 17 of 34 commercial samples of restriction enzymes tested . The method is simple and more sensitive than the procedures used by the commercial suppliers and it is applicable to the quality control testing of more than 100 restriction enzymes. Ned Tijdschr Geneeskd, 1995 Oct 7, 139(40), 2050 - 2 {Extrapulmonary tuberculosis in 3 Dutch patients}; Kruijtzer CM et al.; In three patients, two women aged 71 and 59 years and a man aged 49 who had been living in the Netherlands for a long time and who were admitted because of vague symptoms, extrapulmonary manifestations of tuberculosis were diagnosed: tuberculosis of the lumbar spine with psoas abscess, tuberculous peritonitis and adrenal tuberculosis with Addison's disease in a patient with open pulmonary tuberculosis . All three recovered with tuberculostatic therapy (isoniazid, streptomycin, pyrazinamide and rifampicin). Mol Microbiol, 1995 Oct, 18(1), 151 - 62 The regulator of streptomycin gene expression, StrR, of Streptomyces griseus is a DNA binding activator protein with multiple recognition sites; Retzlaff L et al.; In Streptomyces griseus the expression of at least one streptomycin biosynthetic gene, strB1, is dependent on the pathway-specific activator protein StrR . We show here that StrR is a DNA-binding protein which specifically interacts with the strB1 promoter fragment . Footprinting experiments demonstrate that the StrR protein binds to an inverted repeat located upstream of the strB1 promoter . Further StrR-binding sites having the consensus sequence GTTCGActG(N)11CagTcGAAc were identified in the str-sts gene clusters of S . griseus and Streptomyces glaucescens by sequence comparison, gel retardation, and footprinting studies . The genetic and biochemical evidence strongly supports the model of the StrR protein activating the expression of streptomycin biosynthetic genes by interacting with multiple binding sites within the str-sts gene clusters of S . griseus and S . glaucescens. J Bacteriol, 1995 Oct, 177(20), 5840 - 5 Physiological state of Escherichia coli BJ4 growing in the large intestines of streptomycin-treated mice; Poulsen LK et al.; Growth rates of Escherichia coli BJ4 colonizing the large intestine of streptomycin-treated mice were estimated by quantitative hybridization with rRNA target probes and by epifluorescence microscopy . The ribosomal contents in bacteria isolated from the cecal mucus, cecal contents, and feces were measured and correlated with the ribosomal contents of bacteria growing in vitro at defined rates . The data suggest that E . coli BJ4 grows at an overall high rate in the intestine . However, when taking into account the total intestinal volume and numbers of bacteria present in cecal mucus, cecal contents, and feces, we suggest that E . coli BJ4 in the intestine consists of two populations, one in the mucus which has an apparent generation time of 40 to 80 min and one in the luminal contents which is static. Microbiology, 1995 Oct, 141 ( Pt 10), 2511 - 8 Depression of streptomycin production by Streptomyces griseus at elevated growth temperature: studies using gene fusions; Deeble VJ et al.; Streptomyces griseus ATCC 12475 fails to produce streptomycin when grown at 34 degrees C or above, although growth is appreciable up to at least 37 degrees C . This depression of streptomycin production at elevated growth temperature is manifest equally in liquid and on solid, and with complex and minimal, media . We report studies with gene fusions of the reporter genes aph or xyIE to restriction fragments containing the streptomycin biosynthesis promoter PstrB1 . aph constructs were in high, and xyIE constructs in low, copy number vectors . Two strB1 promoter fragments were used, one requiring activation by the pathway-specific activator StrR of S . griseus, the other reportedly activator independent . PstrB1 expression in the aph constructs in S . griseus and in S . lividans was significantly reduced at 37 degrees C compared to 30 degrees C . Some of this reduction could be explained by lower plasmid copy number at the higher temperature, but strR-dependent expression was clearly temperature controlled . Using the xyIE reporter system, the temperature dependence of PstrB1 expression was confirmed but, surprisingly, the strR dependence of the two promoter fragments differed from that observed in the multicopy aph constructs . These data identify a temperature-dependent promoter which may contribute to the depressive effect of elevated growth temperature on streptomycin production. Endocrinology, 1995 Oct, 136(10), 4448 - 53 Hypothyroidism prevents postnatal changes in rat liver mitochondrial populations defined by rhodamine-123 staining; Almeida A et al.; The effect of hypothyroidism on the percentages of low fluorescence population (LFP) and high fluorescence population (HFP) rhodamine-123-stained mitochondria, respiratory parameters, and ATPase activity were studied in liver mitochondria from early newborn rats . Hypothyroidism prevented the decrease in the percentage of HFP and the subsequent increase in LFP that occurs immediately after birth . This effect coincides with the impairment of mitochondrial respiratory function, as shown by the low respiratory control ratio and the low activity of F0,F1-ATPase found in hypothyroid newborns . All of these changes were reversed by the administration of thyroid hormones . ATP in vitro promotes the conversion of HFP into LFP and increases the respiratory control ratio in hypothyroid newborns, although this effect was not observed after thyroid hormone treatment . The effect of thyroid hormones on both the postnatal changes in mitochondrial populations and in F0,F1-ATPase activity was prevented by cycloheximide, but not by streptomycin . Thus, the observed effects of thyroid hormones on neonatal mitochondria must be accomplished by the induction of the synthesis of some nuclei-coded protein, possibly involved in F0,F1-ATPase assembly. Tuber Lung Dis, 1995 Oct, 76(5), 463 - 7 Failure of drug penetration and acquisition of drug resistance in chronic tuberculous empyema; Elliott AM et al.; We describe a patient with drug-resistant chronic tuberculous empyema in whom substantial differences between achievable pleural fluid and serum drug concentrations were displayed . The ratio of maximum concentration in pleural fluid to serum was especially low for rifampin (4%) but was also low for streptomycin (34%) and ofloxacin (48%) . Subtherapeutic drug concentrations in the pleural fluid may have contributed to acquisition of drug resistance in this case. Lancet, 1995 Sep 9, 346(8976), 675 - 7 Tuberculosis control in resource-poor countries: alternative approaches in the era of HIV; De Cock KM et al.; PIP: WHO projections suggest that the annual number of tuberculosis (TB) cases worldwide will reach 10.2 million by the year 2000 . HIV plays a dominant role in this increase in many resource-poor countries . The internationally recommended treatment regimens for TB combine some of the six major antituberculosis drugs: isoniazid, rifampicin, pyrazinamide, ethambutol, streptomycin, and thiacetazone . WHO treatment guidelines give priority to patients according to the nature of their disease and recommend two regimens of 6-8 months duration, the longer regimen incorporating thiacetazone . Recently, WHO has favored a 6-month treatment regimen given as directly observed therapy (DOT) . The disadvantages of the standard approach are the heavy workload of smear examinations, the complexity of some drug regimens, and the low rates of therapy completion . With the increasing TB case load in areas of high HIV infection prevalence, laboratories cannot do initial as well as follow-up smear examinations . In Botswana the proportion of smear-positive TB cases declined to 40% in 1992, but the overall proportion of patients who had smears performed had declined (52% in 1992) . The multiple regimens in use cause confusion and nonadherence to guidelines . Nonadherence is the major risk factor for the emergence of drug resistance, and low completion rates are the most obvious signs of inadequate control programs . Alternative approaches mean ensuring high completion rates and using the most effective drugs . Regarding diagnosis, research might show that the number of smears could be reduced depending on the initial reading . There is no reason why a rifampicin-based short-course regimen could