Microbios, 1993, 76(308), 161 - 6 Characterization of a plasmid codifying the synthesis of a beta-lactamase produced by Shigella flexneri; Echeverria V et al.; The resistance to beta-lactam antibiotics shown by a strain of Shigella flexneri was plasmid-coded . This plasmid, pMAM-1, when transferred to Escherichia coli K-12 by conjugation, presented the same molecular weight (100 kbp) and conferred the same high level of resistance to ampicillin in the transconjugant as in the wild type strains (MIC, 2048-4096) . Restriction analysis of the plasmid in transconjugants revealed various restrictive sites to some endonucleases (i.e . Bam HI, Eco RI, Pst I, Nco I, Cla I, Sf I and Sau 3AI, Nhe and Hin dIII), and no restrictive sites at all for other endonucleases (such as Xho I, Dra I, Kpn I, and Sal I) . Some restricted DNA fragments were appropriate for cloning and isolation of the beta-lactamase gene present in Shigella flexneri UCSF 129 . This work provides the first step in this direction. Scand J Infect Dis, 1993, 25(5), 569 - 77 Serum antibody responses against shigella lipopolysaccharides and invasion plasmid-coded antigens in shigella infected Swedish patients; Li A et al.; Serum antibody responses to shigella lipopolysaccharide (LPS) and invasion plasmid-coded antigens (Ipa) were studied in 74 Swedish patients with culture verified bacillary dysentery using class-specific enzyme immunoassay (EIA) . Anti-LPS responses were found in 80% and 79% serum samples, respectively, from S . flexneri and S . sonnei infected patients and anti-Ipa responses in 60% and 43%, respectively . The mean anti-Ipa IgG antibody titres in S . flexneri infected patients remained high for 4-6 months after onset while the anti-LPS IgG antibody titres had dropped to normal levels . The specificity of EIA for shigella Ipa was 90% and for S . dysenteriae, S . flexneri and S . sonnei LPSs it varied between 84% and 90% . No close correlations between the anti-LPS and anti-Ipa antibody responses were observed indicating that they may be differently regulated . The dynamics of the serum antibody responses indicates that an anti-LPS response is a good indicator of a recent shigella infection and an anti-Ipa IgG response a good indicator of a previous infection. Bull World Health Organ, 1993, 71(5), 571 - 8 Initiation of food supplements and stopping of breast-feeding as determinants of weanling shigellosis; Ahmed F et al.; The association between the period elapsed since weaning and the risk of shigellosis was assessed between 1 November 1987 and 30 November 1989 for a cohort of 1085 Bangladeshi children aged < 3 years . The children were followed for 1 month after exposure to Shigella spp . in their residential neighbourhoods, and the 268 who developed microbiologically confirmed (n = 118) or clinically presumptive (n = 150) shigellosis were compared with the 817 control children who did not develop either syndrome . No increase in risk was noted among breast-fed infants who received food supplements within the previous 3 months compared with those who had received supplements for longer (adjusted odds ratio (OR) = 1.2; 95% confidence interval (CI) = 0.4-3.0) . However, compared with breast-fed children, non-breast-fed children had an increased risk (adjusted OR = 2.0; 95% CI = 1.3-2.9; P < 0.001), which was largely attributable to a substantially increased risk in the 3 months after stopping breast-feeding (adjusted OR = 6.6; 95% CI = 2.9-14.6; P < 0.001) . The early post-cessation risk was equivalent for confirmed and presumptive shigellosis, but was particularly pronounced among the severely malnourished (adjusted OR = 10.2; 95% CI = 3.1-33.3; P < 0.001) . This complex temporal pattern of risk highlights the need for precise definitions of weaning to facilitate identification of children at high risk for invasive diarrhoeal syndromesPIP: Between November 1987 and November 1989, International Centre for Diarrhoeal Disease Research, Bangladesh, (ICDDR,B) scientists followed for 1 month 1085 children, younger than 3 years old, who lived in the Matlab . They compared data on the 268 children who developed microbiologically confirmed on clinically presumptive shigellosis during the 30-day period with data on 817 children who did not develop symptoms of shigellosis . Children who were not breast fed were at greater risk of shigellosis than those who were breast fed (adjusted odds ratio {AOR} = 2; p .001) . This risk of shigellosis was much higher during the 1st 3 months after a child stopped breast feeding (AOR = 6.6; p .001) than it was 3 months after cessation of breast feeding (AOR = 1.4) . Children who suffered from severe malnutrition were at an especially high post-cessation risk of shigellosis (AOR= 10.2; p .001) . These findings show a complex evolution of risk with different stages of weaning, which emphasizes the need for a precise definition of weaning in epidemiologic studies . The limited period of high risk for shigellosis (i.e., the 1st 3 months after breast feeding cessation) and the wide range in ages at which children cease breast feeding elevates the complexity of executing successful vaccination programs against shigellosis, especially live oral vaccines . The vaccines must be administered early in life, before cessation of breast feeding, in order for them to protect against shigellosis . Yet, ingestion of breast milk may reduce the immunogenicity of the vaccines . Arch Immunol Ther Exp (Warsz), 1993, 41(2), 153 - 7 Induction of tumor necrosis factor and interleukin 6 by outer membrane proteins of Shigella in spleen cells and macrophages of mice; Czarny A et al.; The ability of outer membrane proteins (OMP) of Shigella flexneri to induce tumor necrosis factor (TNF) and interleukin 6 (IL-6) production by spleen cells and macrophages of mice was investigated . Treatment of spleen cells with OMP resulted in the release of only traces of TNF activity . In contrast, macrophages treated with OMP produced moderate levels of TNF . OMP was also found to be an inducer of IL-6 . Both spleen cells and macrophages, treated with OMP, were found to produce substantial levels of this cytokine . The effect of OMP on the release of TNF and IL-6 was dose and time dependent, maximal production being reached at 10 micrograms of OMP after 20 h . The ability of OMP to induce production of these cytokines may explain part of the previously described immunomodulatory effects of this preparation on the immune system. Turk J Pediatr, 1993 Jan-Mar, 35(1), 23 - 36 Hemolytic-uremic syndrome (HUS): a clinicopathological study of 15 cases; Tinaztepe K et al.; Although hemolytic-uremic syndrome (HUS) is a clinico-pathological entity, renal biopsies are usually not indicated for diagnosis, and therefore, studies concerning the histological aspects of the syndrome are few . This study mainly describes the morphological characteristics of 15 tissue-diagnosed sporadic cases of HUS . The ages of the patients ranged between 10 mos . to 15 yrs., with five being under two . The male/female ratio was 2:3 . The prodromal phase was present in 10 patients (67%) with gastrointestinal symptoms in four patients (27%) with neurological symptoms, and in three patients (20%) with upper respiratory infections . Five patients had HUS associated with diarrhea (D+) (three infants and two children), while the remaining ten patients (two infants and eight children) had no diarrhea (D-) . E . coli was identified in the stool of four of the D+ cases, one of which was also associated with Shigella . The shortest clinical course was 14 days and the longest 55 days in 13 patients . The disease recurred after three months in one patient, and on three occasions in 15 months after onset of HUS in the other . Fourteen patients died and one biopsy-diagnosed case recovered after the acute phase . All patients had anemia (Hb 3.4-10 g/dl) and acute renal failure . Seven cases demonstrated Burr cells, eight cases had thrombocytopenia and six cases oliguria/anuria . Microscopic hematuria was detected in four cases and gross hematuria in two cases . All patients revealed proteinuria and azotemia (40-200 mg/dl) . Five/five (100%) cases had decreased creatinine clearance, 12/14 (86%) cases had increased uric acid levels, 9/14 (64%) cases had an electrolyte imbalance . Light microscopy revealed microangiopathic type involvement of the glomeruli in all cases . According to additional findings, the cases were classed into three histological groups: type 1 showing cortical necrosis (3 cases), type 2 predominant glomerular and arteriolar involvement (11 cases) and type 3 predominant arterial involvement (1 case) . All cases were considered primary HUS except for one which was associated with membranous glomerulonephritis . (D+) HUS cases were predominantly of the microangiopathic type, similar to the (D-) group; the latter being contrary to the literature . Hypertension was present in 67% of cases and there was no correlation found between the clinical duration of HUS and the histological type . All five patients studied immunohistologically revealed a nonspecific type fibrinogen deposition . Extra-renal microangiopathy was demonstrated in the adrenals, stomach, pancreas, liver and skin in two necropsies studied. Chin J Biotechnol, 1993, 9(1), 49 - 55 High level expression of Shiga toxin B subunit of Shigella dysenteriae serotype 1 in Escherichia coli; Su G et al.; In this study the gene encoding the Shiga toxin (Stx) was cloned from the chromosomal DNA of Shigella dysenteriae serotype 1 (W30864) . The Stx gene was located in a 4.5kb EcoRI fragment . The biological assay revealed that the hybrid plasmid pMGC001 containing the Stx gene could produce Shiga toxin . The amount of Stx was 16 times more than that produced by its parent . The cloned strain showed cytotoxic, entorotoxic and neurotoxic activities . The gene for Stx-B subunit was subcloned into a plasmid vector pJLA503 from the plasmid pMGC001 . The B subunit could be expressed at high level in E . coli and has been purified in large quantities . The polyclonal and monoclonal antibodies against B subunit were raised . Western blot showed that they could react specifically to the B subunit. Rev Latinoam Microbiol, 1993 Jan-Mar, 35(1), 1 - 6 {Antimicrobial activity of human colostrum against enteropathogens . Preliminary study}; Solorzano-Santos F et al.; The antimicrobial activity of the colostrum serum from ten women has been evaluated . The activity against Escherichia coli, Shigella sonnei and Klebsiella pneumonia at three different bacterial populations was determined (1 x 10(4), 1 x 10(5) and 1 x 10(6) UFC/ml) . Antimicrobial activity against the three strains was found . Bactericidal activity was observed to inocula of 1 x 10(4) UFC/ml in 8/10 sera against E . coli, in 6/10 sera against S . sonnei, and in 3/10 sera against K . pneumonia; in the rest of the cases, sera were bacteriostatic . With inocula of 1 x 10(5) UFC/ml there was bactericidal activity in 4/10 sera against E . coli and S . sonnei and in 1/10 against K . pneumonia . Lastly, with inocula of 1 x 10(6) UFC/ml there was bactericidal activity in 4/10 sera against E . coli, 1/10 against S . sonnei and none against K . pneumoniae . The results suggest that because of the antimicrobial properties of human milk the risk of intestinal infections by enteropathogens is less. Scand J Infect Dis, 1993, 25(6), 713 - 9 Comparative efficacy of pivmecillinam and cotrimoxazole in acute shigellosis in children; Prado D et al.; In a prospective randomized double-blind trial, pivmecillinam was compared with cotrimoxazole (TMP-SMX), both given orally for a period of 5 days, for the treatment of 59 children with shigellosis . 29 patients were treated with pivmecillinam and 30 with cotrimoxazole . 14% of shigella organisms isolated were resistant to pivmecillinam and 21% to TMP-SMX . The diarrhea persisted for a mean (+/- SD) period of 74 +/- 24.8 h in the pivmecillinam-treated patients versus 73.8 +/- 34 h in the TMP-SMX-treated patients . Duration of fever, positive stool culture, visible blood, occult blood, and pus cells in the stools were similar for both treatment groups . Five patients (17%) in the pivmecillinam group and 4 patients (13%) in the cotrimoxazole group fulfilled the clinical criteria that defined treatment failure . One patient (3.4%) in the pivmecillinam group and 2 (6.6%) in the TMP-SMX group evidenced recurrence of the diarrheal symptoms at the follow-up visit . No major drug-related side effects were observed in either group . We concluded that pivmecillinam is equivalent to cotrimoxazole in the treatment of shigellosis in children. Southeast Asian J Trop Med Public Health, 1993, 24 Suppl 1, 280 - 3 A clinico-hematological profile of hemolytic-uremic syndrome; Dayal R et al.; Hemolytic uremic syndrome (HUS) is defined as microangiopathic hemolytic anemia, thrombocytopenia and uremia . It is an important cause of acute renal failure (ARF) in children all over the world . The present study was carried out to assess the incidence, clinical presentation, hematological and biochemical profile of children presenting with HUS from 1987 to 1990 . Out of the 100 cases who presented with ARF 22 had HUS . A majority of these children were males below 1 year of age, and had a prodromal phase of mainly gastrointestinal manifestations lasting for about a week . Anemia was a constant feature followed by bleeding diathesis, mainly melena and purpura . Neurological manifestations included altered sensorium, irritability, coma, hypertensive encephalopathy and convulsions . Renal problems mainly included oliguria, hypertension, hematuria and edema . Investigations revealed thrombocytopenia and microangiopathic hemolytic anemia in all cases . Evidence of disseminated intravascular coagulation (DIC) was observed in 3 cases as decreased fibrinogen levels, increased fibrinogen degradation products and deranged clotting studies . Blood biochemistry revealed azotemia in all cases, hyponatremia in 5 cases, hypernatremia in 3 cases and hyperkalemia in 12 cases . Stool culture showed the presence of Shigella in 8, E . coli in 6 and Klebsiella in 4 cases . Out of 22 cases of HUS, 15 were treated conservatively; of these 2 died . Both of these deaths were due to DIC 7 children were put on peritoneal dialysis; only 1 child died in this group . Factors affecting the outcome were duration of oliguria, levels of blood urea and presence of encephalopathy.(ABSTRACT TRUNCATED AT 250 WORDS) Microbiol Immunol, 1993, 37(4), 331 - 4 Chemical analysis of lipopolysaccharides of Shigella sonnei form II strains expressed by cloned form I antigen genes; Okamura N et al.; A compositional sugar analysis was carried out on lipopolysaccharide (LPS) from Shigella sonnei form II in which a plasmid with cloned form I antigen genes had been introduced . The recipient form II strains contained galactose, glucose, heptose, glucosamine, and 2-keto-3-deoxyoctonic acid (KDO) (2: 3: 1: 2: 2) in its LPS, while the transformant form I LPS contained, besides these sugars, N-acetyl-L-altrosaminouronic acid as an additional sugar constituent, which is known to be one of the antigenic determinants of form I antigen. Ann Trop Paediatr, 1993, 13(2), 121 - 31 Diarrhoea caused by Escherichia coli; Hart CA et al.; Since the mid-1940s, Escherichia coli has been recognized as a cause of diarrhoea . Subsequently it has been shown that at least five different pathogenic mechanisms are used to cause disease . Enterotoxigenic E . coli (ETEC) and enteropathogenic E . coli (EPEC) produce a noninflammatory diarrhoea, whereas enteroinvasive E . coli (EIEC), enterohaemorrhagic E . coli (EHEC) and enteroaggregative E . coli (EAggEC) produce an inflammatory diarrhoea . ETEC are a major cause of diarrhoea in infants (up to three episodes per year) and travellers . They produce diarrhoea by attaching to the small intestinal mucosa and elaborate one or both of heat labile and heat stable toxins . EPEC attach firmly to the intestinal mucosa leading to dissolution of the brush border by inducing vesiculation of the microvilli . This process is known as attaching-effacement, and in the jejunum and ileum results in a loss of brush border disaccharidase enzymes and a large area of absorptive surface . EPEC are a major cause of summer diarrhoea in infants and neonatal diarrhoea . EIEC attach to colonic enterocytes, penetrate by an endocytotic mechanism and replicate therein . This results in necrosis and stripping of large areas of colonic mucosa and a dysentery similar to but usually less severe than Shigella dysentery . EHEC produce attaching-effacement to the terminal ileal and colonic mucosa and release the toxins, verocytotoxin (VT) 1 or 2 . These kill colonic enterocytes and produce haemorrhagic colitis . In addition, VT can damage vascular endothelial cells, leading to haemolytic uraemic syndrome . The role of EHEC in diarrhoea in children in the tropics is not known . The most recently described group are the EAggEC . They damage and blunt colonic villi by haemorrhagic necrosis, although the precise pathogenic mechanisms are unclear . EAggEC are a major cause of chronic diarrhoea in children . Although certain O-serotypes are associated with the different enteropathic E . coli, serotyping is not sufficiently specific or sensitive for use as a diagnostic tool . Specific diagnosis is expensive and time consuming and depends upon demonstration of the pathogenicity trait, and the pathogenicity gene(s) or their gene product(s) . At present, to undertake such testing is not recommended for routine diagnosis but is most useful when surveys of the aetiology of acute and chronic diarrhoea are undertaken. J Pediatr, 1993 Jan, 122(1), 82 - 4 Acute myocarditis associated with Shigella sonnei gastroenteritis; Rubenstein JS et al.; We describe two patients with acute myocarditis temporally associated with an acute Shigella sonnei gastroenteritis . This association has not been described in children and should be considered in children with shigellosis who do not respond to rehydration therapies. JAMA, 1992 Dec 9, 268(22), 3208 - 12 An international foodborne outbreak of shigellosis associated with a commercial airline; Hedberg CW et al.; OBJECTIVE--To determine the source of an international outbreak of shigellosis associated with consumption of food served by a Minnesota-based airline . DESIGN--Cohort studies of players and staff of a Minnesota-based professional football team and passengers on flights with a confirmed case of outbreak-associated Shigella sonnei infection . SETTING--Community- and industry-based studies conducted from October through November 1988 . PARTICIPANTS--Sixty-five football team players and staff, and 725 airline passengers in the cohort studies . RESULTS--Twenty-one (32%) of 65 football players and staff developed shigellosis that was associated with consumption of cold sandwiches prepared at the airline flight kitchen (relative risk {RR}, 17.1; 95% confidence interval {Cl}, 2.4 to 120; P < .001) . Confirmed or probable shigellosis was identified among 240 passengers on 219 flights to 24 states, the District of Columbia, and four countries between September 14 and October 13 . An outbreak-associated strain of S sonnei was isolated from football players and staff, airline passengers, and flight attendants . Thirty (4.1%) of 725 passengers on 13 flights with confirmed cases had confirmed or probable shigellosis . Illness was associated with consumption of cold food items served on the flights and prepared by hand at the airline flight kitchen (RR, 5.7; 95% Cl, 1.4 to 23.5; P < .01) . CONCLUSIONS--This international outbreak of shigellosis was identified only because of the occurrence of an index outbreak involving a professional football team . Prevention of Shigella transmission in mass catering establishments may require reduction of hand contact in the preparation of cold food items or elimination of these items from menus. J Autoimmun, 1992 Dec, 5(6), 675 - 90 Bacterial agents protect against autoimmune disease . I . Mice pre-exposed to Bordetella pertussis or Mycobacterium tuberculosis are highly refractory to induction of experimental autoimmune encephalomyelitis; Lehmann D et al.; Infectious agents have often been implicated in the etiology of autoimmune diseases . Here we show that bacteria may also play a role in resistance to autoimmune diseases . SJL/J and (SJL/J x BALB/c)F1 mice are genetically susceptible to induction of experimental autoimmune encephalomyelitis (EAE), a murine model for human demyelinating autoimmune diseases such as multiple sclerosis . We studied the effect of several bacteria on the development of EAE and found that exposure of SJL/J or (SJL/J x BALB/c)F1 mice to Mycobacterium tuberculosis or Bordetella pertussis consistently rendered mice highly refractory to subsequent induction of the disease . Other bacteria such as Escherichia coli, Shigella and Staphylococcus aureus were found to be less effective, or were protective only if specific immunization procedures were used . Furthermore, M . tuberculosis and B . pertussis were protective irrespective of the route of administration and minute amounts (as low as 0.5 micrograms) of M . tuberculosis were sufficient to protect EAE-susceptible mice against induction of the disease . Interestingly, these bacteria, which are commonly used to promote development of EAE, conferred the highest degree of protection against the disease . The M . tuberculosis-induced protection was found to be associated with active suppression mechanisms mediated by T lymphocytes capable of transferring protection to naive syngeneic mice . These findings indicate that certain bacteria may protect against the development of autoimmune diseases . These results also suggest the potential use for still-unidentified bacterial agents in the manipulation of certain autoimmune diseases. Epidemiol Infect, 1992 Dec, 109(3), 463 - 72 High level resistance to trimethoprim, cotrimoxazole and other antimicrobial agents among clinical isolates of Shigella species in Ontario, Canada--an update; Harnett N; A total of 598 isolates of Shigella species (24 S . dysenteriae, 254 S . flexneri, 30 S . boydii, 290 S . sonnei) submitted to the Ontario Public Health Laboratories in 1990 were tested for their susceptibility to 14 antimicrobial agents by the agar dilution method . Overall 79.6% of isolates were resistant to one or more antimicrobial agents and 52.0% were resistant to four or more . Trimethoprim resistance ranged from 26.7% among isolates of S . boydii to 39.4% among S . flexneri strains . The majority of the 224 TMP resistant isolates (88.8%) demonstrated high level resistance (MIC > 1000 mg/l) to trimethoprim . Resistance to cotrimoxazole increased from 3% in 1978 to between 26.7 and 37.6% in 1990 . MICs for 90% of isolates (MIC90s) for ampicillin, ticarcillin and piperacillin were 128 to > 256 mg/l, > 256 for tetracycline and chloramphenicol, and > 2.0/38.0 for cotrimoxazole . These results from the Canadian Province of Ontario emphasize the need for prudent use of antimicrobial agents in the treatment of shigellosis. J Med Microbiol, 1992 Dec, 37(6), 382 - 4 Protection from Shigella sonnei infection by immunisation of rabbits with Plesiomonas shigelloides (SVC 01); Sayeed S et al.; Plesiomonas shigelloides, an organism commonly found in water, is only rarely associated with diarrhoea in man . P . shigelloides serotype O:17 (SVC O1), which is antigenically similar to Shigella sonnei, was found to be neither virulent nor toxic for rabbits . Rabbits immunised by feeding with P . shigelloides (SVC O1) were completely protected against an oral challenge with 10(10) cells of S . sonnei but non-immunised rabbits were not . P . shigelloides (SVC O1) may be a useful vaccine strain for shigellosis. J Med Microbiol, 1992 Dec, 37(6), 364 - 7 Serum antibodies to verotoxin-producing Escherichia coli (VTEC) strains in patients with haemolytic uraemic syndrome; Kishore K et al.; Serological evidence of infection with verotoxin-producing Escherichia coli (VTEC) was sought in 28 patients suffering from haemolytic uraemic syndrome (HUS) and 25 age- and sex-matched controls . ELISA was used to detect anti-lipopolysaccharide (LPS) antibodies to E . coli strains O157, O111, O26 and NCTC 10418, a non-VTEC strain, and Shigella dysenteriae O1 . Sera from 19 of the HUS patients but from none of the 25 controls had significant antibody levels to the verotoxin-producing bacteria . Sera from 13 patients reacted with only one LPS of the four verotoxin-producing bacteria; sera from six reacted with more than one LPS antigen but not with LPS of E . coli NCTC 10418 . Paired sera taken 2-3 weeks apart were obtained from 20 HUS patients; 14 of these had high levels of antibody in the acute phase sample . Analysis of antibody levels in the convalescent sera showed that one patient had an increase, one was unchanged and 12 patients had a decrease in antibody to the verotoxin-producing bacteria. J Pediatr, 1992 Dec, 121(6), 852 - 6 Concentration of milk secretory immunoglobulin A against Shigella virulence plasmid-associated antigens as a predictor of symptom status in Shigella-infected breast-fed infants; Hayani KC et al.; We conducted a prospective, community-based study of healthy breast-fed Mexican infants to determine the protective effects of anti-Shigella secretory IgA antibodies in milk . Milk samples were collected monthly, and stool culture specimens were obtained weekly and at the time of episodes of diarrhea . Nineteen breast-fed infants were found to have Shigella flexneri, Shigella boydii, or Shigella sonnei in stool samples . Ages of the 10 infants with symptomatic infection and the nine with asymptomatic infection did not differ significantly . Milk samples collected up to 12 weeks before infection were evaluated by enzyme-linked immunosorbent assay for secretory IgA antibodies against lipopolysaccharides of S . flexneri, S . boydii serotype 2, S . sonnei, and virulence plasmid-associated antigens . The geometric mean titers of anti-Shigella antibodies to virulence plasmid-associated antigens in milk received before infection were eightfold higher in infants who remained well than in those in whom diarrhea developed . The significance of milk secretory IgA directed against lipopolysaccharide was less clear . We conclude that human milk protects infants against symptomatic shigella infection when it contains high concentrations of secretory IgA against virulence plasmid-associated antigens. J Bacteriol, 1992 Dec, 174(23), 7661 - 9 MxiJ, a lipoprotein involved in secretion of Shigella Ipa invasins, is homologous to YscJ, a secretion factor of the Yersinia Yop proteins; Allaoui A et al.; Shigella flexneri causes bacillary dysentery by invading epithelial cells of the colonic mucosa . The invasion process requires the synthesis and secretion of the virulence plasmid-encoded Ipa proteins . Using TnphoA mutagenesis, we have identified two virulence plasmid genes, mxiJ and mxiM, that encode proteins exported by the general export pathway . Analysis of the MxiJ and MxiM deduced amino acid sequences suggested that mxiJ and mxiM might encode lipoproteins, which was confirmed by {3H}palmitate labeling of MxiJ:PhoA and MxiM:PhoA fusion proteins . A mxiJ mutant was unable to invade HeLa cells, to induce the formation of plaques on confluent monolayers of HeLa cells, and to provoke keratoconjunctivitis in guinea pigs . In addition, secretion of seven polypeptides, including IpaA, IpaB, and IpaC, was abolished in the mxiJ mutant . Sequence comparisons indicated that MxiJ and MxiH, which is encoded by a gene located upstream from mxiJ, are homologous to the Yersinia enterocolitica YscJ and YscF proteins, respectively. Zentralbl Bakteriol, 1992 Dec, 277(4), 429 - 35 Composition of lipid A in the S and R forms of Shigella dysenteriae serovar 1; Sourek J et al.; A chemical analysis was performed of lipid A, isolated by acid hydrolysis of the lipopolysaccharide from the S and R forms of Shigella dysenteriae serovar 1 . Differences in the moiety of both lipids and sugars were compared . The lipid portion consisted of a homologous series of fatty acids ranging from C12:0 to C18:0 (predominant homologues, C12:0, C14:0 and C16:0) and the homologous series of 3-hydroxy acids ranging from C12:0 to C16:0 (predominant homologue, 3-OH-C14:0) . The major sugar portion consisted of D-glucosamine . The toxicity of lipid A in mice (LD50) ranged between 300-400 micrograms/mouse, and values from the Limulus amebocyte lysate assay were recorded as titres of 10(-5) to 10(-6) mg/ml. Kansenshogaku Zasshi, 1992 Dec, 66(12), 1628 - 33 {Shigella flexneri strains having a new type antigen 89-141}; Matsushita S et al.; Two Shigella strains (89-141 and 89-11) isolated from the stool of patients returning from abroad (both from India) in Tokyo in 1989 showed an atypical serologic reaction of agglutination with only polyvalent antiserum to S . flexneri prepared commercially . These strains had the typical biochemical characteristics of S . flexneri and were biochemically identical . Both strains were positive for Sereny test in guinea pig eye and cell-invasion test in HeLa cells . The strains also had virulence-plasmid encoding outer membrane proteins, indicating pathogenicity . The results of antigenic analyses showed that the strains were serologically identical to each other and gave significant cross-reactions with S . flexneri variant Y that has only group 3, 4 factor antigen . However, the results of reciprocal absorption tests showed that the O antigen of these strains was not identical to S . flexneri variant Y, and they were confirmed to have an additional type-specific antigen which is not included among the known S . flexneri type antigen I-VI or provisional type 88-893 which were proposed by us in 1992 . Furthermore, one stock strain (TSH508) formally identified as S . flexneri variant X has this type antigen, suggesting that the new antigen can be classified into two subtypes by combination of group factor antigen . Strain 89-141 is designated as the test strain for this new type antigen of S . flexneri. Pediatr Res, 1992 Dec, 32(6), 689 - 92 Effects of a protein-rich diet during convalescence from shigellosis on catch-up growth, serum proteins, and insulin-like growth factor-I; Kabir I et al.; Shigellosis in children can cause growth retardation, worsening of malnutrition, and hypoproteinemia . To assess the effects of ingestion of a protein-rich diet during convalescence, 22 children aged 2 to 4 y with culture-proven shigellosis were randomly assigned after 5 d of antibiotic treatment to 21-d feeding regimens of either a 150 kcal/kg/d high-protein diet with 15% of calories as protein or an isocaloric control diet with 6% of calories as protein . At the start and end of dietary treatment, weight, height, mid-arm circumference, skinfold thickness, serum protein concentrations, and serum IGF-I were measured . Means of weight gain and increases in mid-arm circumference were greater in children fed high-protein diets than those fed control diets (1.23 versus 0.76 kg; 1.40 versus 0.96 cm; p < 0.05) . Mean increase in height in children fed high-protein diets (0.83 cm) was not significantly greater than with control diets (0.74 cm) . Mean increases in serum concentrations of total protein, prealbumin, and retinol-binding protein were greater in the high-protein group than in controls (p < 0.05) . Mean serum concentrations of IGF-I were low in both groups before treatment {4.2 +/- 2.6 nmol/L (31.9 +/- 19.6 ng/mL) in controls; 3.1 +/- 3.4 nmol/L (24.0 +/- 26.3 ng/mL) in the high-protein group} but increased more in the high-protein group {39.0 +/- 16.2 nmol/L (298 +/- 124 ng/mL)} than in the control group {16.7 +/- 9.2 nmol/L (128 +/- 70 ng/mL), p < 0.01}.(ABSTRACT TRUNCATED AT 250 WORDS) Zentralbl Bakteriol, 1992 Dec, 277(4), 419 - 28 Characterization of a lipopolysaccharide encoded by a recombinant Shigella sonnei plasmid in Escherichia coli K-12; Seltmann G et al.; The genetic information to synthesize the S-specific region of Shigella sonnei phase I lipopolysaccharide (LPS) is localized on a 180 kb plasmid which is lost quite readily . A recombinant plasmid derivative remaining stable in the bacteria was shown to determine the S-specific region of the LPS which is completely identical with that of a S . sonnei phase I strain following transfer in Escherichia coli K-12 . However, the length control in polysaccharide biosynthesis is lost at least partially. J Bacteriol, 1992 Dec, 174(23), 7500 - 8 Acetylation of O-specific lipopolysaccharides from Shigella flexneri 3a and 2a occurs in Escherichia coli K-12 carrying cloned S . flexneri 3a and 2a rfb genes; Yao Z et al.; Most of the Shigella flexneri O-specific serotypes result from O-acetyl and/or glucosyl groups added to a common O-repeating unit of the lipopolysaccharide (LPS) molecule . The genes involved in acetylation and/or glucosylation of S . flexneri LPS are physically located on lysogenic bacteriophages, whereas the rfb cluster contains the biosynthesis genes for the common O-repeating unit (D.A.R . Simmons and E . Romanowska, J . Med . Microbiol . 23:289-302, 1987) . Using a cosmid cloning strategy, we have cloned the rfb regions from S . flexneri 3a and 2a . Escherichia coli K-12 containing plasmids pYS1-5 (derived from S . flexneri 3a) and pEY5 (derived from S . flexneri 2a) expressed O-specific LPS which reacted immunologically with S . flexneri polyvalent O antiserum . However, O-specific LPS expressed in E . coli K-12 also reacted with group 6 antiserum, indicating the presence of O-acetyl groups attached to one of the rhamnose components of the O-repeating unit . This was confirmed by measuring the amounts of acetate released from purified LPS samples and also by the chemical removal of O-acetyl groups, which abolished group 6 reactivity . The O-acetylation phenotype was absent in an E . coli strain with an sbcB-his-rfb chromosomal deletion and could be restored upon conjugation of F' 129, which carries sequences corresponding to a portion of the deleted region . Our data demonstrate that E . coli K-12 strains possess a novel locus which directs the O acetylation of LPS and is located in the sbcB-rfb region of the chromosomal map. Nippon Saikingaku Zasshi, 1992 Nov, 47(6), 777 - 81 {Chemical and serological study of lipopolysaccharide isolated from Shigella flexneri 88-893 possessing a new type-antigen}; Toshima Y et al.; The O-specific polysaccharide chain which represents a new type-antigen in lipopolysaccharide (LPS) of Shigella flexneri 88-893 was investigated . The O-polysaccharide chain was found to be composed of repeating units comprising rhamnose, N-acetylglucosamine and glucose (3:1:2) . In the passive hemolysis test, group-6 antiserum of S . flexneri exhibited a high hemolytic titer (50% hemolysis titer: 7,900) against sheep red blood cells (SRBC) sensitized with intact 893 LPS, but virtually no hemolytic activity against SRBC sensitized with alkali-treated 893 LPS . None of the type-specific antisera (I-VI), showed any significant hemolytic titer against SRBC sensitized with either intact or alkali-treated 893 LPS . Thus, 893 LPS contained both the group-6 antigen and a new type-antigen which is distinct from any known type-antigen of S . flexneri. J Infect, 1992 Nov, 25(3), 273 - 8 Serological diagnosis of infection by Shigella dysenteriae-1 in patients with bacillary dysentery; de Silva DG et al.; A total of 192 samples of serum from 113 Sri Lankan patients with clinical dysentery was examined for antibodies of the IgM class to the lipopolysaccharides (LPSs) of Shigella dysenteriae-1 and Escherichia coli O157:H7 . By means of ELISA and immunoblotting, 59 patients were found to have serum antibodies to the LPS of S . dysenteriae-1 only . Four samples from one patient were found to contain serum antibodies to the LPSs of both S . dysenteriae-1 and E . coli O157:H7 . Antibodies to the LPS of S . dysenteriae-1 were also detected in 16 samples from 25 children, from Sri Lanka, with no previous history of dysentery; one of these children also had antibodies to the LPS of E . coli O157:H7 . Analysis of 16 samples from apparently healthy children in the U.K . showed that only one serum contained antibodies to the LPS of S . dysenteriae-1 . This patient had a history of recent travel to Pakistan . The isolation of S . dysenteriae-1 remains the preferred test for the diagnosis of bacillary dysentery . The use of serology as a means of providing evidence of infection with S . dysenteriae-1, however may prove to be a useful adjunct to cultural techniques but needs to be validated in an area where this organism is endemic. FEMS Microbiol Lett, 1992 Nov 1, 77(1-3), 229 - 33 Purification and partial characterization of two azoreductases from Shigella dysenteriae type 1; Ghosh DK et al.; Two azoreductases (I and II) were purified to homogeneity from extracts of Shigella dysenteriae (type 1) . Azoreductase I was a dimer of identical subunits of M(r) 28,000, whereas azoreductase II was a monomer of 11,000 M(r) . Both were flavoproteins, each containing 1 mol of FMN per mol enzyme . Both NADH and NADPH functioned as electron donors for the azoreductases . Azoreductase I used Ponceau SX, Tartrazine, Amaranth and Orange II as substrates . Azoreductase II utilized all the dyes except Amaranth. Eur J Clin Nutr, 1992 Nov, 46(11), 833 - 8 Decreased food intake in children with severe dysentery due to Shigella dysenteriae 1 infection; Rahman MM et al.; Factors that affect food intake in acute shigellosis were studied in 82 children aged 24-59 months . Children were offered an energy-dense milk-cereal-oil-based diet every 2 h . Food intake was compared between children with Shigella dysenteriae 1 infection and those infected with other Shigella spp (predominantly S . flexneri) . Mean energy intake in the first 48 h was 435 kJ/kg.d in children infected with S . dysenteriae 1 and 536 kJ/kg.d in children infected with other Shigella spp (P < 0.001) . Febrile children ate significantly (P < 0.05) less food than afebrile ones (469 vs 517 kJ/kg.d) . Food intake remained significantly (P < 0.001) less in children infected with S . dysenteriae 1 after controlling for the effect of fever . The results show that food intake is significantly reduced in dysentery due to S . dysenteriae 1 infection compared to that of other Shigella species; however, adequate calorie intake can be maintained by providing frequent energy-dense meals despite anorexia, fever, abdominal pain and diarrhoea. Ann Intern Med, 1992 Nov 1, 117(9), 727 - 34 Treatment of shigellosis: III . Comparison of one- or two-dose ciprofloxacin with standard 5-day therapy . A randomized, blinded trial; Bennish ML et al.; OBJECTIVE: To determine whether a single dose, or 2 doses, of ciprofloxacin are as effective as 5-day, 10-dose therapy for the treatment of shigellosis in adult men who are moderately to severely ill . DESIGN: Randomized, double-blind clinical trial . SETTING: A diarrhea treatment center in the capital city of a developing country, Bangladesh . PATIENTS: A total of 128 adult men with dysentery of less than 96 hours duration . All had Shigella organisms isolated from a culture of stool . INTERVENTIONS: Patients were randomly assigned to receive either a single 1-gram dose of ciprofloxacin at admission to the study (single-dose group; n = 40), a 1-gram dose of ciprofloxacin at admission and 24 hours later (2-dose group; n = 43), or 500 mg of ciprofloxacin every 12 hours for 5 days (10 dose group; n = 35) . All patients were hospitalized for 6 days . MEASUREMENTS: Stools were collected individually; their character and consistency were recorded and cultured daily . A physical examination and recording of symptoms were done daily, and the temperature was measured every 4 hours . Therapy was considered to have failed in patients who did not have improvement in the signs and symptoms of dysentery after 72 hours of therapy or in patients who on study day 5 had more than nine stools, or more than two watery stools, or were febrile . RESULTS: There were no treatment failures in the 78 patients infected with species of Shigella other than Shigella dysenteriae type 1 . Among the 40 patients infected with S . dysenteriae type 1, treatment failed in 4 of the 10 patients who received single-dose therapy, 2 of the 15 patients who received 2-dose therapy, and none of the 15 patients who received 10-dose therapy (P = 0.017, single-dose therapy group compared with 10-dose group; P = 0.15 for the single-dose group compared with the 2-dose group; P > 0.2 for the 2-dose group compared with the 10-dose group) . CONCLUSIONS: A single 1-gram dose of ciprofloxacin is effective therapy for patients infected with species of Shigella other than S . dysenteriae type 1 . Single-dose therapy is inferior to 10-dose therapy for treating patients infected with S . dysenteriae type 1. J Infect Dis, 1992 Nov, 166(5), 1181 - 4 An analysis of the quantitative relationship between oral temperature and severity of illness in experimental shigellosis; Mackowiak PA et al.; The relationship between oral temperature and other parameters of illness was examined in 139 adult volunteers infected experimentally with Shigella sonnei . In subjects developing clinical disease, peak temperature correlated positively with total number of signs and symptoms other than fever (rxy = .71, P < .001), stool volume (rxy = .41, P < .001) and number of stools produced during the illness (rxy = .46, P < .001) . Peak temperature correlated negatively with incubation period (rxy = -.34, P = .007) but exhibited no apparent correlation with duration of illness . The average oral temperature during illness correlated positively with number of other signs and symptoms of infection but not with stool volume or stool number . These results suggest that in clinical investigations involving S . sonnei, and perhaps with other pathogenic microorganisms, oral temperature is a useful quantitative marker for estimating disease severity. J Bacteriol, 1992 Nov, 174(21), 6981 - 91 Molecular analysis of the glpFKX regions of Escherichia coli and Shigella flexneri; Truniger V et al.; We have identified a new gene, glpX, belonging to the glp regulon of Escherichia coli, located directly downstream of the glpK gene . The transcription of glpX is inducible with glycerol and sn-glycerol-3-phosphate and is constitutive in a glpR mutant . glpX is the third gene in the glpFKX operon . The function of GlpX remains unknown . GlpX has an apparent molecular weight of 40,000 on sodium dodecyl sulfate-polyacrylamide gels . In addition to determining the E . coli glpX sequence, we also sequenced the corresponding glpFKX region originating from Shigella flexneri, which after transfer into E . coli was instrumental in elucidating the function of glpF in glycerol transport (D . P . Richey and E . C . C . Lin, J . Bacteriol . 112:784-790, 1972) . Sequencing of the glpFKX region of this hybrid strain revealed an amber mutation instead of the tryptophan 215 codon in glpF . The most striking difference between the E . coli and S . flexneri DNA was found directly behind glpK, where two repetitive (REP) sequences were present in S . flexneri, but not in the E . coli sequence . The presence or absence of these REP sequences had no effect on transport or on growth on glycerol . Not including the REP sequence-containing region, only 1.1% of a total of 2,167 bp sequenced was different in the two sequences . Comparison of the sequence with those in the EMBL data library revealed a 99% identity between the last third of glpX and the first part of a gene called mvrA . We show that the cloned mvrA gene (M . Morimyo, J . Bacteriol . 170:2136-2142, 1988) originated from the 88-min region of the Escherichia coli chromosome and not, as reported, from the 7-min region and that the gene product identified as MvrA is in fact encoded by a gene distal to glpX. FASEB J, 1992 Nov, 6(14), 3265 - 74 Structural basis of antigenic specificity and design of new vaccines; Arnon R et al.; This manuscript describes the design of new vaccines based on synthetic peptides . To this end, we first analyze the structural basis of antigenic reactivity and specificity and the various types of epitopes that form the mosaics of macromolecular antigens, as well as the regulatory mechanisms involved in immune recognition . A distinction is made between sequential or continuous epitopes, and discontinuous or conformational ones, which are the majority of epitopes in globular proteins . In this context it is of particular interest to identify epitopes reacting with B cells and T cells, respectively, or with cytotoxic T cells, in association with the major histocompatibility cell-surface antigens, and the role of these interactions in protective immunity . Identification of such epitopes in proteins of viral, bacterial, or parasitic organisms led to the synthesis of peptides, which when used in conjunction with appropriate carriers and/or adjuvants induced neutralizing antibodies . Particular examples are described, including: bacterial epitopes and mainly those of toxins of diphtheria, cholera, and shigella, leading not only to neutralizing antibodies but also to protective immunity against the deleterious effects of the respective toxins; parasite epitopes, such as those leading to anti-malaria vaccine, based on either the sporozoite or the merozoite stage antigens; viral epitopes leading to protective immunity, with special emphasis on influenza virus where induction of CTL is crucial; and finally, synthetic peptide vaccines against HIV, which should lead to broad specificity protective immunity while avoiding the risks of a vaccine based on the infectious agent . The rapid recent progress in this field, as described in this review, increases the prospect of constructing successful synthetic peptide vaccines in the not too distant future. Rev Med Chil, 1992 Nov, 120(11), 1261 - 6 {Shigellosis in children of the IX region of Chile: clinical and epidemiologic aspects and antibiotic sensitivity}; Boehme C et al.; Ninety four children with diarrhea and a positive stool culture for Shigella, hospitalized at the Hospital Regional de Temuco, were studied . Forty six percent of patients were less than two years old . Forty two percent of microorganisms were resistant to Ampicillin, 45% to trimethoprim/sulfamethoxazole, 8% to tetracycline and none to chloramphenicol . Isolated species were Shigella flexneri 83% and Shigella sonnei 17% . Seventy nine percent of patients had fever, 60% dysentery and 21.3% seizures . Ninety two percent of symptomatic family contacts had a positive stool culture for Shigella . Due to the high incidence of resistance to ampicillin and trimethoprim/sulfamethoxazole, these antimicrobials are not recommended as the first choice treatment of Shigellosis in the Ninth region of Chile. Eur J Epidemiol, 1992 Nov, 8(6), 856 - 60 Features of cholera and Vibrio parahaemolyticus diarrhoea endemicity in Calabar, Nigeria; Utsalo SJ et al.; The clinical and epidemiological features of acute vibrio diarrhoeal disease were studied in 881 patients seen at the University of Calabar Teaching Hospital (UCTH), Calabar, Nigeria, between January and December 1989 . Stools and rectal swabs of patients and randomly-selected control subjects were microscopically and culturally examined for the presence of enteric pathogens . Households of vibrio diarrhoea cases and matched controls were visited for ecologic studies . Of a total of 108 (12.3%) culturally-confirmed bacterial diarrhoeas, 47 (43.5%) were due to Escherichia coli, 33 (30.6%) to Vibrio cholerae-01 (classical and El Tor biotypes) and V . parahaemolyticus, while shigellae and salmonellae accounted for 29 (26.9%) and 9 (8.3%) cases, respectively . Most cholera case households clustered within the ancient neighbourhood of the inner city, characterized by poorly developed water and sewage disposal systems . A preponderance of vibrio diarrhoea patients were children < or = 10 years . Adult cases involved mostly females . The only case of diarrhoea-related death involved an eight-month old child with kwashiorkor and V . parahaemolyticus infection . Incidence of vibrio diarrhoeas was seasonal, with most cases occurring during the dry season followed by subsidence at the onset of rainy season . Bimodal peaks of vibrio diarrhoeal episodes observed over the period appeared to coincide with periods of acute water scarcity, high temperature, increased fishing activities and trade traffic on the Calabar River estuary . Of the environments sampled, only clam shells from a case household and river sediments yielded vibrio pathogens on culture . Ecological factors that are capable of stabilizing a focus of vibrio diarrhoea endemicity in this area are highlighted. J Clin Microbiol, 1992 Nov, 30(11), 2996 - 9 Differentiation of Shigella flexneri strains by rRNA gene restriction patterns; Faruque SM et al.; We studied the restriction endonuclease cleavage patterns of rRNA genes (ribotypes) of 72 clinical isolates of Shigella flexneri representing eight serotypes to determine whether ribotyping could be used to distinguish S . flexneri strains and to compare the discriminating ability of the method with that of serotyping . By using a cloned Escherichia coli rRNA operon as the probe, Southern blot hybridization of restriction endonuclease-digested total DNA was carried out . Ribotyping of the isolates with each of the five restriction endonucleases BamHI, EcoRI, HindIII, PstI, and SalI generated reproducible restriction patterns . However, HindIII produced the optimum digestion pattern of the rRNA genes and was more useful than the other enzymes used in differentiating strains . Analysis of the 72 isolates showed 11 different HindIII cleavage patterns of their rRNA genes . Four of these HindIII-generated ribotypes could be further differentiated into two to four subribotypes by using PstI . The results indicate that ribotyping has an application for differentiation of S . flexneri strains and can complement serotyping . Definition of strains in terms of both serotype and ribotype may be of greater use in epidemiological studies. Antimicrob Agents Chemother, 1992 Oct, 36(10), 2346 - 8 Activities of newer fluoroquinolones against Shigella sonnei; John JF Jr et al.; The activities of six fluoroquinolones were determined for 117 separate strains of Shigella sonnei . The order of increasing activity (MICs for 90% of strains tested) was enoxacin (0.25 micrograms/ml), temafloxacin (0.032 micrograms/ml), sparfloxacin (0.016 micrograms/ml), CI-960 (0.008 micrograms/ml), ciprofloxacin (0.008 micrograms/ml), and PD-131628-2 (0.008 micrograms/ml) . These data, along with results of killing and mutational rate studies, showed that all six fluoroquinolones were highly inhibitory against S . sonnei and five fluoroquinolones were rapidly and persistently bactericidal. J Infect Dis, 1992 Oct, 166(4), 792 - 6 Enteropathogens associated with acute and persistent diarrhea in Bangladeshi children less than 5 years of age; Baqui AH et al.; A longitudinal study of diarrhea was carried out from May 1988 to April 1989 by household surveillance of 705 children less than 5 years old in rural Bangladesh . Stool samples were examined for enteric pathogens at the beginning of each diarrheal episode . For persistent episodes, stool examination was repeated on days 15-17 of the illness . For each case of persistent diarrhea, stool samples from age-matched acute diarrheal and healthy controls were examined . Compared with healthy controls, cases of diarrhea were associated with Shigella species (P = .07) and rotavirus (P less than .05) . Diffusely adherent Escherichia coli (P less than .05) and cryptosporidia (P = .07) were the only enteropathogens associated with persistent diarrhea in comparison with acute diarrhea . No more than 15% of children had the same class of pathogen identified from stool on both days 1-3 and days 15-17, indicating that persistent infection was uncommon . However, a different enteropathogen was frequently found on days 15-17, suggesting that sequential infection may be a cause of persistent diarrhea. Zentralbl Bakteriol, 1992 Oct, 277(3), 334 - 9 The isolation of Plesiomonas shigelloides in polymicrobial septicaemia originating from the biliary tree; Korner RJ et al.; The first two cases are reported in which Plesiomonas shigelloides was isolated from patients with mixed aerobic/anaerobic septicaemia originating from the biliary tree . The first patient who was previously well survived after removal of a gangrenous gallbladder . The second patient suffered from an extrahepatic cholangiocarcinoma and died of infection thus highlighting the poor prognostic outcome of P . shigelloides septicaemia in immunocompromised patients . Furthermore these cases demonstrate that P . shigelloides can be isolated from mixed infections and may act synergistically with other bacteria to produce disease. APMIS, 1992 Oct, 100(10), 954 - 6 beta-lactamases in Shigella; Schumacher H et al.; The occurrence of resistance and production of beta-lactamases was investigated in 60 Shigella strains . Ampicillin resistance was found in 28 (47%) of the isolates, the resistance being more frequent in Sh . flexneri than in Sh . sonnei . All strains were susceptible to cefotaxime, mecillinam, and ciprofloxacin . The beta-lactamases produced by Shigella were similar to TEM-1, OXA-1, or the low-level chromosomally mediated cephalosporinase produced by Escherichia coli . The beta-lactamases produced by Sh . flexneri were most often the OXA-1-like enzymes. J Bacteriol, 1992 Oct, 174(20), 6498 - 507 Identification of a B subunit gene promoter in the Shiga toxin operon of Shigella dysenteriae 1; Habib NF et al.; The Shiga toxin operon (stx) is composed of A and B subunit genes which are transcribed as a bicistronic mRNA from a promoter which lies 5' to the stxA gene . Northern (RNA) blot and primer extension analyses revealed the existence of a second stxB gene transcript . Recombinant plasmids which carried the stxB gene without the stx operon promoter and with the influence of a vector promoter abrogated produced STX B polypeptides, suggesting that the stxB gene mRNA was transcribed from an independent promoter and was not produced by endoribonucleotic processing of the bicistronic mRNA . Examination of the DNA sequences 5' to the stxB gene transcription initiation site which were carried by the recombinant plasmids revealed a region with high homology to the consensus for Escherichia coli promoters . Deletion and mutation of this region affected StxB and holotoxin production, establishing its role in the regulation of the stxB gene . Comparison of the promoters by using a transcription analysis vector revealed that the stxB gene promoter differed from the stx operon promoter in that was approximately sixfold less efficient and was not repressed by iron . Identification of a second promoter in the stx operon indicates that independent transcription of the stxB gene may regulate overproduction of the STX B polypeptides and may contribute to the 1A:5B subunit stoichiometry of the holotoxin. J Bacteriol, 1992 Oct, 174(20), 6359 - 67 vacB, a novel chromosomal gene required for expression of virulence genes on the large plasmid of Shigella flexneri; Tobe T et al.; Shigellae, the causative agents of bacillary dysentery, are capable of adhering to and invading epithelial cells and spreading into adjacent cells . A chromosomal mutant of Shigella flexneri 2a YSH6000 with reduced invasive capacity was isolated by Tn5 insertion mutagenesis . The linkage of the mutant phenotype to the Tn5 insertion was determined by P1 phage transduction . The site of the Tn5 insertion was assigned to a NotI chromosomal restriction map, confirming that the virulence-associated locus, designated vacB, is a new locus on the chromosome . In the vacB mutant, production of the four plasmid-encoded virulence antigens, IpaB, -C, and -D and VirG, decreased to a low level compared with that in the wild type . In contrast, levels of transcription of the operons for virG, ipa, region-3.4, region-5, virF, and virB on the large plasmid, as determined by Northern dot blotting, were unaffected in the vacB mutant . Furthermore, transcriptional activation of the ipa operon by exploiting a tac promoter could not restore the vacB mutant to production of the same levels of the IpaB, -C, and -D proteins as those in the wild type, indicating that the vacB locus is involved in expression of the vir genes on the large plasmid at the posttranscriptional level . Cloning followed by nucleotide sequencing of the vacB region showed it to contain a 2,280-bp open reading frame encoding an 86.9-kDa protein located 669 bp downstream from the 3' end of the open reading frame for the purA gene . Disruption of the vacB gene of other serotypes of Shigella spp . and enteroinvasive Escherichia coli (EIEC) resulted in reduced expression of virulence phenotypes, indicating that the vacB gene encodes a novel type of virulence-associated gene required for the full expression of the virulence phenotype of Shigella spp . and EIEC. Infect Immun, 1992 Oct, 60(10), 4088 - 99 Unipolar reorganization of F-actin layer at bacterial division and bundling of actin filaments by plastin correlate with movement of Shigella flexneri within HeLa cells; Prevost MC et al.; Shigella flexneri causes bacillary dysentery, an invasive disease of colonic epithelial cells in humans . The capacity of bacteria, once they have entered into a cell and escaped the phagocytic vacuole, to spread intracellularly and directly to adjacent cells without further extracellular passage is a key factor in invasion of the epithelial layer . Movement of intracellular bacteria is dependent upon the polymerization of actin; concentration of the formed filaments to one end of the bacterium is associated with initiation of movement . This movement may lead to the formation of a protrusion at the cell surface through which the bacterium passes to an adjacent cell . Development of these protrusions in infected HeLa cells is described, with emphasis on two critical observations . First, initiation of movement is coupled with bacterial division since elongation of the bacterial body is associated with relocalization of the previously uniformly distributed layer of actin to one pole of the bacterium . Second, the actin-bundling protein plastin appears to bundle the actin filaments just posterior to the bacterium, producing an ongoing contraction of the cylindrical actin tail that may be associated with forward movement of the bacterium within the protrusion. Acta Virol, 1992 Oct, 36(5), 443 - 9 Effect of enterovirus infection on susceptibility of HeLa cells to Shigella flexneri invasivity; Marchetti M et al.; Invasiveness of Shigella flexneri M90T in HeLa cells was significantly increased when cells were preinfected with poliovirus 1, coxsackievirus B3 and echovirus 6 . This effect was dependent on the dose of virus used, evident at early stages of viral infection and lasted hours before the appearance of a cytopathic effect . An increase of bacterial invasion ability was also noticed when HeLa cells were incubated with UV-inactivated enteroviruses . This enhancing effect obtained with both viable and UV-inactivated enteroviruses was not observed when in coinfection experiments HN555, a mutant of S . flexneri M90T which lacked invasive properties, was used . The data presented here suggest that the early steps of enterovirus infection induce some alterations of HeLa cells which are responsible for the enhancing of the invasiveness of S . flexneri M90T, but not sufficient to promote internalization of a non-invasive strain. Epidemiol Infect, 1992 Oct, 109(2), 273 - 82 Molecular epidemiology of Shigella infections in Israel; Yavzori M et al.; The DNAs of Shigella sonnei or Shigella dysenteriae type 1 strains isolated in outbreaks of shigellosis or in sporadic cases were analysed by restriction fragment length polymorphism (RFLP) . Southern blots of the DNAs of 36 S . sonnei isolates digested by 8 restriction enzymes were hybridized with an Escherichia coli rRNA probe . The S . sonnei strains were unexpectedly diverse in their RFLP . Antibiotypes of the same isolates showed clusters of strains corresponding to the various outbreaks . On the other hand, RFLP analysis suggested concomitant multiple sources of infection rather than a common source and thereby introduced a new insight in the epidemiology of shigellosis . RFLP was also used to trace S . dysenteriae type 1 transmission in a recent cluster of clinical cases . Although antibiotic resistance patterns indicated the presence of more than one strain, RFLP analysis showed that the six isolates were identical clones and suggested the loss of an R episome after one person-to-person passage. JAMA, 1992 Sep 23-30, 268(12), 1578 - 80 A critical appraisal of 98.6 degrees F, the upper limit of the normal body temperature, and other legacies of Carl Reinhold August Wunderlich; Mackowiak PA et al.; OBJECTIVE--To evaluate critically Carl Wunderlich's axioms on clinical thermometry . DESIGN--Descriptive analysis of baseline oral temperature data from volunteers participating in Shigella vaccine trials conducted at the University of Maryland Center for Vaccine Development, Baltimore . SETTING--Inpatient clinical research unit . PARTICIPANTS--One hundred forty-eight healthy men and women aged 18 through 40 years . MAIN MEASUREMENTS--Oral temperatures were measured one to four times daily for 3 consecutive days using an electronic digital thermometer . RESULTS--Our findings conflicted with Wunderlich's in that 36.8 degrees C (98.2 degrees F) rather than 37.0 degrees C (98.6 degrees F) was the mean oral temperature of our subjects; 37.7 degrees C (99.9 degrees F) rather than 38.0 degrees C (100.4 degrees F) was the upper limit of the normal temperature range; maximum temperatures, like mean temperatures, varied with time of day; and men and women exhibited comparable thermal variability . Our data corroborated Wunderlich's in that mean temperature varied diurnally, with a 6 AM nadir, a 4 to 6 PM zenith, and a mean amplitude of variability of 0.5 degrees C (0.9 degrees F); women had slightly higher normal temperatures than men; and there was a trend toward higher temperatures among black than among white subjects . CONCLUSIONS--Thirty-seven degrees centigrade (98.6 degrees F) should be abandoned as a concept relevant to clinical thermometry; 37.2 degrees C (98.9 degrees F) in the early morning and 37.7 degrees C (99.9 degrees F) overall should be regarded as the upper limit of the normal oral temperature range in healthy adults aged 40 years or younger, and several of Wunderlich's other cherished dictums should be revised. Pharmacoeconomics, 1992 Oct, 2(4), 305 - 23 Pharmacoeconomics of the therapy of diarrhoeal disease; Nathavitharana KA et al.; We review the pathophysiology of intestinal water and electrolyte transport leading to diarrhoea, the currently available pharmacological strategies for its treatment, and the economic implications of such treatments . Diarrhoea occurs most frequently and is associated with highest mortality in children under 5 . Oral rehydration therapy (ORT) is the cornerstone of its management . The safety and efficacy of ORT in the prevention of death from dehydration, both in field and also in hospital settings, are now well established . Because it is also inexpensive, ORT is widely applicable worldwide . More recently, rice-based ORT has emerged, based on well known traditional remedies for diarrhoea in southeast Asia and the Far East . Rice-based ORT has the advantage of being more culturally acceptable, readily available even in rural homes in developing countries, and is more effective in reducing stool output and the duration of diarrhoea, compared with conventional glucose-electrolyte solutions such as World Health Organization ORT . For infants, the well known antidiarrhoeal properties of human milk needs emphasis for a variety of reasons including economic ones . Data concerning the economic benefits to a nations' health budget as a result of nationwide implementation of oral rehydration solution (ORS) use are limited . Available data from individual centres in developing countries, if projected to national level, would incur considerable economic advantage . Except for a few notable infections such as shigellosis, cholera, amoebiasis and giardiasis, the widespread use of antibiotics in acute diarrhoea, still a common practice in many developing countries, has no proven value and may be detrimental . The economic implications of antibiotic abuse in the treatment of diarrhoea in developing countries is enormous . Despite the availability of a wide spectrum of pharmacological agents for diarrhoea reviewed in this article, only a few such agents are of proven clinical efficacy: corticosteroids, aminosalicylates and immunosuppressants in the treatment of inflammatory bowel disease and opioid derivatives such as loperamide which may be useful in protracted diarrhoea in children and in disorders where rapid gastrointestinal transit is the main cause of diarrhoea . Opioids are not recommended for acute infective diarrhoea in childhood . Octreotide, a somatostatin analogue, is reported to be useful in the treatment of secretory diarrhoea due to noninfective causes and in the treatment of intractable diarrhoea associated with AIDS . Its high cost and need for parenteral administration prevent its wider application.(ABSTRACT TRUNCATED AT 400 WORDS) Am J Trop Med Hyg, 1992 Sep, 47(3), 276 - 83 Efficacy of bovine milk immunoglobulin concentrate in preventing illness after Shigella flexneri challenge; Tacket CO et al.; The protective efficacy of oral bovine immunoglobulin concentrates derived from colostrum against challenge with Shigella flexneri was studied in healthy adult volunteers in a randomized, double-blind fashion . Volunteers were given a product consisting of hyperimmune immunoglobulin concentrate with a high titer of anti-S . flexneri 2a lipopolysaccharide (LPS) with sodium bicarbonate or a control preparation with sodium bicarbonate three times a day for seven days . On the third day of treatment, volunteers received a challenge of 10(3) colony-forming units of S . flexneri 2a strain 2457T . None of the volunteers who received the high-titered hyperimmune product became ill, compared with 45% of volunteers who received the placebo (P less than 0.05) . The duration of shedding of the challenge organism was decreased, and the active immune responses to S . flexneri LPS were less frequent and of lower magnitude in volunteers given the immunoglobulin concentrate than in those in the control group . High-titered, orally administered bovine immunoglobulin concentrate protects against shigellosis and may be useful in preventing shigellosis among travelers, military personnel, and individuals at risk during a Shigella outbreak. Pediatrics, 1992 Sep, 90(3), 406 - 11 Community-based evaluation of the effect of breast-feeding on the risk of microbiologically confirmed or clinically presumptive shigellosis in Bangladeshi children; Ahmed F et al.; To assess the association between breast-feeding and the risk of microbiologically confirmed or clinically presumptive shigellosis, the authors performed a case-control analysis of Bangladeshi children younger than 3 years of age who were followed up for 1 month after exposure to Shigella in their residential neighborhoods . Two hundred sixty-nine cases with culture-confirmed shigellosis (n = 119) or clinically presumptive shigellosis (culture-negative dysentery, n = 150) were compared with 819 controls without Shigella diarrhea or other invasive diarrheal illnesses . The odds ratio relating breast-feeding to confirmed or presumptive shigellosis, adjusted for potentially confounding variables, was 0.48 (95% confidence interval = 0.32 to 0.72; P less than .001), suggesting a substantial protective effect . The protective association decreased with age but was still significant during the third year of life; appeared to be directly related to the degree of stunting; and was equivalent for confirmed and presumptive shigellosis . Notably, the protective association remained substantial against episodes due to Shigella which were resistant to at least one of the antibiotics customarily used for treatment of Shigella diarrhea (age-adjusted odds ratio = 0.40; 95% confidence interval = 0.22 to 0.74; P less than .01) . These data suggest that breast-feeding confers a high level of protection against shigellosis throughout the first 3 years of life, especially among nutritionally compromised children, and thereby underscore the importance of promotion of breast-feeding as a central component of Shigella control programs in less developed settings. Mol Plant Microbe Interact, 1992 Sep-Oct, 5(5), 390 - 6 Determinants of pathogenicity in Xanthomonas campestris pv . vesicatoria are related to proteins involved in secretion in bacterial pathogens of animals; Fenselau S et al.; One of the model systems investigated for studying plant bacterial pathogenesis is Xanthomonas campestris pv vesicatoria, the causal agent of bacterial spot disease of pepper and tomato . Genes necessary for both basic pathogenicity and the induction of the hypersensitive response in resistant plants (hrp genes) were previously isolated from X . c . pv . vesicatoria and characterized genetically . As a first step toward functional analysis, part of the hrp gene cluster, making up several loci, was sequenced . Here, we report the first indications of the function of hrp genes . Striking similarities to proteins from the mammalian pathogens Shigella flexneri, Yersinia enterocolitica, Y . pestis, and other bacteria were discovered . Proteins encoded by genes within the X . c . pv . vesicatoria loci hrpA, hrpB, and hrpC are similar to ATPases and to Yersinia Ysc and LcrD proteins, which are involved in secretion of Yop proteins, a particular class of essential pathogenicity factors produced by Yersinia species . This finding indicates, for the first time, that the fundamental determinants of pathogenicity may be conserved among bacterial pathogens of plants and animals . We hypothesize that hrp genes are involved in the secretion of molecules essential for the interaction of X . c . pv . vesicatoria with the plant. J Diarrhoeal Dis Res, 1992 Sep, 10(3), 146 - 50 Efficacy of norfloxacin for shigellosis: a double-blind randomised clinical trial; Bhattacharya MK et al.; In a double-blind, randomised, clinical trial on 122 adults with acute Shigella dysentery, 60 patients were treated with norfloxacin and 62 with nalidixic acid . Of these, 32 patients in the norfloxacin group and 28 patients in the nalidixic acid group had Shigella in their stool . Patients of the two treatment groups were clinically comparable on admission . No significant differences in clinical responses were observed in the two groups among the Shigella-positive cases, Shigella-negative cases and among the total cases . All isolates of Shigella were susceptible to norfloxacin, whereas 13.8% of the strains were resistant to nalidixic acid. J Diarrhoeal Dis Res, 1992 Sep, 10(3), 139 - 45 Regulation of the SLT-1A toxin operon by a ferric uptake regulatory protein in toxinogenic strains of Shigella dysenteriae type 1; Svinarich DM et al.; The regulation of Shiga toxin expression in a clinical isolate of S . dysenteriae 1 by the Fe-Fur (Iron-ferric uptake regulatory protein) repressor complex was investigated . The presence of an endogenous Fur repressor protein capable of binding to either a Fur binding consensus sequence or the regulatory region of SLT-1A was determined in toxinogenic strains of S . dysenteriae . Plasmid constructs bearing Fur binding sites fused to readily assayable reporter genes were used . Plasmid pSC27.1 contains a 21 bp synthetic oligonucleotide Fur protein binding consensus sequence located upstream to the gene for beta-galactosidase . Plasmid pSC105 contains the regulatory sequences of Shiga-like toxin-1A located upstream to the gene for alkaline phosphatase . In an analogous fashion to Shiga toxin regulation in S . dysenteriae 1, transformants bearing either pSC27.1 or pSC105 plasmid DNA were repressed in gene product expression when grown in minimal medium supplemented with iron . Conversely, transformants were de-repressed when grown under iron limiting conditions . These data suggest the presence of Fe-Fur mediated regulation of toxinogenesis in clinical isolates of S . dysenteriae. Acta Paediatr Suppl, 1992 Sep, 381, 27 - 31 Epidemiology of persistent diarrhea and etiologic agents in Mirzapur, Bangladesh; Henry FJ et al.; To determine the epidemiology and etiologic agents of persistent diarrhea we carried out an intensive diarrhea surveillance on children less than six years old in rural Bangladesh . From March 1987 to February 1989 we examined 363 children through diarrhea recall interviews and analyzed stool samples of all diarrhea cases for potential pathogens . Results showed that children had an average of two episodes per year and the incidence rate of diarrheal episodes defined as acute (< 14 d) and persistent (> or = 14 d) varied similarly with age . The peak incidence (episodes/child/year) of acute diarrhea (2.8) and persistent diarrhea (0.8) occurred in the 6-11 months age group . The data showed that an episode tended to be prolonged if the stool was loose/mucoid or bloody at onset . Aggregative adherent Escherichia coli was found significantly more often at onset in persistent than in acute episodes, whereas Shigella, Aeromonas, Giardia and toxigenic E . coli were isolated with less frequency in persistent than acute episodes . This suggests that other factors might be more important in the development of persistent diarrhea than specific pathogens. Cesk Epidemiol Mikrobiol Imunol, 1992 Sep, 41(4), 215 - 7 {Isolation of a rare serovar of Plesiomonas shigelloides}; Moravcik P et al.; The authors describe the isolation of a rare serovar Plesiomonas shigelloides from a patient with diarrhoea . The isolated strain belongs according to a combined Japanese-Czechoslovak antigenic scheme to serovar 024 H"o" . The interesting finding draws attention to the possibility of routine departments to contribute to investigations of the incidence, importance and antigenic structure of this bacterial species. Infect Immun, 1992 Aug, 60(8), 3287 - 95 mxiA of Shigella flexneri 2a, which facilitates export of invasion plasmid antigens, encodes a homolog of the low-calcium-response protein, LcrD, of Yersinia pestis; Andrews GP et al.; The plasmid-encoded invasion plasmid antigen (Ipa) export accessory locus of Shigella flexneri 2a, mxiA, was cloned, and the complete DNA sequence of the gene was determined . The mixA open reading frame was found to encode a polypeptide of 74.03 kDa with a pI of 5.02 . A hydropathy analysis of the predicted protein revealed a hydrophilic C terminus and an extremely hydrophobic N terminus without a cleavable signal sequence but with several potential membrane-spanning regions . While a homology search did not reveal any significant relatedness of the mxiA DNA sequence to any known bacterial gene sequences, the derived amino acid sequence of MxiA was found to be highly homologous (68%) to the sequence of the protein encoded by the low-calcium-response locus, lcrD, of Yersinia pestis . The lcrD encodes an inner membrane regulatory protein that has an N-terminal membrane anchor and that is implicated in facilitating the export of Y . pestis outer membrane proteins (G . V . Plano, S . S . Barve, and S . C . Straley, J . Bacteriol . 173:7293-7303, 1991) . Congo red binding, HeLa cell invasion, and Ipa excretion were restored in two avirulent mxiA fusion mutants when they were transformed with a cloned copy of the mxiA gene . Furthermore, the expression of the cloned mxiA gene was independent of any vector-specified promoter, suggesting that the transcription of mxiA is driven by its own promoter in this clone . In contrast, the overexpression of mxiA that resulted when it was placed under the control of the lac promoter was found to be deleterious in Escherichia coli . We conclude that mxiA is a homolog of the Y . pestis lcrD locus and may function similarly in S . flexneri, either by directly affecting the excretion of virulence factors or by regulating the expression of export accessory genes. Pediatr Infect Dis J, 1992 Aug, 11(8), 644 - 7 Ceftibuten and trimethoprim-sulfamethoxazole for treatment of Shigella and enteroinvasive Escherichia coli disease; Prado D et al.; In a prospective randomized study at two clinical sites, ceftibuten was compared with trimethoprim-sulfamethoxazole (TMP-SMX), both given orally for a period of 5 days, for the treatment of dysentery . Twenty-two children were found to have bacillary dysentery caused by Shigella and/or enteroinvasive Escherichia coli . All organisms isolated were susceptible to ceftibuten; 6 of 20 Shigella strains and 4 of 5 enteroinvasive E . coli were resistant to TMP-SMX . The diarrhea persisted for a mean (+/- SD) period of 2.4 +/- 1.4 days in the ceftibuten-treated patients vs . 3.4 +/- 1.7 days in the TMP-SMX-treated patients . The duration of fever was similar for both treatment groups . Patients treated with ceftibuten or TMP-SMX had equivalent clinical responses unless the pathogen was found to be TMP-SMX-resistant . Those who were randomized to receive TMP-SMX but who were eventually found to have TMP-SMX-resistant organisms had significantly more stools at days 3, 4 and 5 (P less than 0.02 to less than 0.00006) with more watery consistency for these days (P less than 0.02 to less than 0.005) compared to patients treated with ceftibuten . No clinical relapses were reported and no drug-related side effects were observed . We conclude that ceftibuten is at least as effective as TMP-SMX in the treatment of diarrhea caused by Shigella and enteroinvasive E . coli in children. J Clin Microbiol, 1992 Aug, 30(8), 2165 - 8 Presence of specific immunoglobulin A-secreting cells in peripheral blood after natural infection with Shigella sonnei; Orr N et al.; The appearance of antigen-specific immunoglobulin A (IgA) antibody-secreting cells (ASCs) following natural infection with Shigella sonnei during a common-source outbreak caused by this organism was evaluated in a modified enzyme-linked immunosorbent assay (ELISPOT) . A mean IgA ASC value of 2,131.6/10(6) cells against homologous S . sonnei lipopolysaccharide (LPS) was detected in blood samples obtained from patients with bacteriologically proven S . sonnei shigellosis 5 and 10 days after the onset of disease . In the same blood samples, the level of ASC measured against heterologous antigen (Shigella flexneri serotype 2a LPS) was significantly lower than that of the homologous antigen (mean value, 33.12/10(6) cells) . Furthermore, the mean number of activated B cells that secreted anti-S . sonnei LPS antibodies was significantly higher among patients with S . sonnei shigellosis than it was among patients with non-Shigella diarrhea (2.5/10(6) cells; standard error, 1.0) and healthy subjects (5.1/10(6) cells; standard error, 2.3) (P less than 0.05) . The anti-LPS IgA ASC activity was easily detected within 5 days of the onset of disease, a point at which the levels of anti-S . sonnei LPS IgG and even IgA antibodies were hardly detectable in serum. Mol Microbiol, 1992 Aug, 6(16), 2387 - 95 Identification and characterization of virK, a virulence-associated large plasmid gene essential for intercellular spreading of Shigella flexneri; Nakata N et al.; Seven virulence loci have been identified by Tn5 insertion mutagenesis on the large 230 kb plasmid (pMYSH6000) of Shigella flexneri 2a . In this study, we used Tn10 insertion mutagenesis and identified a novel virulence locus on pMYSH6000 responsible for bacterial spread . Characterization of the invading bacteria of the Tn10 insertion mutants in the epithelial cells revealed that the bacteria were capable of at least some intracellular spreading but not intercellular spreading . Immunoblot analysis of lysates of the Tn10 insertion mutants with a VirG-specific antipeptide antibody revealed diminished levels of the 116 kDa VirG protein . The virG mRNA in the mutants, however, was expressed at the same level as that in the wild type . The DNA region required for the virulence phenotype was localized to a 1.6 kb DNA sequence in the SalI-K fragment on the plasmid, and thus the locus was designated virK . Expression of virK in Escherichia coli using a T7 RNA polymerase-dependent promoter system yielded a 36 kDa protein . The nucleotide sequence of 1642 bp encoding VirK function was determined, and an open reading frame encoding 316 amino acid residues was shown to encode the VirK protein . The virK region was highly conserved among the large virulence plasmids of shigellae and enteroinvasive Escherichia coli . These results suggest that VirK function is an essential virulence determinant for shigellae involved in the expression of virG gene product at post-transcriptional level. Mol Microbiol, 1992 Aug, 6(15), 2113 - 24 Temperature regulation of Shigella virulence: identification of the repressor gene virR, an analogue of hns, and partial complementation by tyrosyl transfer RNA (tRNA1(Tyr)); Hromockyj AE et al.; virR is the central regulatory locus required for coordinate temperature-regulated virulence gene expression in the human enteric pathogens of Shigella species . Detailed characterization of VirR+ clones revealed that virR consisted of a 411 bp open reading frame (ORF) that mapped to a chromosomally located 1.8kb EcoRI-AccI DNA fragment from Shigella flexneri . Insertional inactivation of the virR ORF at a unique HpaI restriction site resulted in a loss of VirR+ activity . The virR ORF nucleotide sequence was virtually identical to the Escherichia coli hns gene, which encodes the histone-like protein, H-NS . Based on the predicted amino acid sequence of E . coli H-NS, only a single conservative base-pair change was identified in the virR gene . An additional clone, designated VirRP, which only partially complemented the virR mutation, was also characterized and determined by Southern hybridization and nucleotide sequence analysis to be unique from virR . Subclone mapping of this clone indicated that the VirRP phenotype was a result of the multiple copy expression of the S . flexneri gene for tRNA(Tyr) . These data constitute the first direct genetic evidence that virR is an analogue of the E . coli hns gene, and suggest a model for temperature regulation of Shigella species virulence via the bacterial translational machinery. FEMS Microbiol Lett, 1992 Aug 1, 74(1), 57 - 62 Analysis of DNA encoding 23S rRNA and 16S-23S rRNA intergenic spacer regions from Plesiomonas shigelloides; East AK et al.; Amplification of the gene encoding 23S rRNA of Plesiomonas shigelloides by polymerase chain reaction (PCR), with primers complementary to conserved regions of 16S and the 3' end of 23S rRNA genes, resulted in a DNA fragment of approximately 3 kb . This fragment was cloned in Escherichia coli and its nucleotide sequence determined . The region encoding 23S rRNA shows high homology with the published sequences of 23S rRNA from other members of the gamma division of Proteobacteria . The sequence of the intergenic spacer region, between the 16S and 23S rRNA genes, was determined in a further two clones . In one the sequence of a single tRNA(Glu) was found which was absent from the other two . This variation in sequence suggests that the different clones may be derived from different ribosomal RNA operons. Nature, 1992 Jul 9, 358(6382), 167 - 9 Shigella flexneri induces apoptosis in infected macrophages; Zychlinsky A et al.; The Gram-negative bacterial pathogen Shigella flexneri causes dysentery by invading the human colonic mucosa . Bacteria are phagocytosed by enterocytes, escape from the phagosome into the cytoplasm and spread to adjacent cells . After crossing the epithelium, Shigella reaches the lamina propria of intestinal villi, the first line of defence . This tissue is densely populated with phagocytes that are killed in great numbers, resulting in abscesses . The genes required for cell invasion and macrophage killing are located on a 220-kilobase plasmid . We report here on the mechanism of cytotoxicity used by S . flexneri to kill macrophages . Each of four different strains was tested for its capacity to induce cell death . An invasive strain induced programmed cell death (apoptosis), whereas its non-invasive, plasmidcured isogenic strain was not toxic; neither was a mutant in ipa B (ref . 10) (invasion protein antigen), a gene necessary for entry . A non-invasive strain expressing the haemolysin operon of Escherichia coli induced accidental cell death (necrosis), demonstrating that other bacterial cytotoxic mechanisms do not lead to apoptosis . This is the first evidence that an invasive bacterial pathogen can induce suicide in its host cells. J Clin Microbiol, 1992 Jul, 30(7), 1636 - 41 Antibodies to shiga holotoxin and to two synthetic peptides of the B subunit in sera of patients with Shigella dysenteriae 1 dysentery; Levine MM et al.; Acute- and convalescent-phase sera from 18 Thai patients and convalescent-phase sera from two Israeli patients and one Bangladeshi patient with Shigella dysenteriae 1 (Shiga) dysentery were tested by enzyme-linked immunosorbent assay to detect antibodies that bind S . dysenteriae lipopolysaccharide (LPS), Shiga holotoxin, or two synthetic peptides representing epitopes from the B subunit of Shiga toxin . Paired sera from 24 Maryland adults with Shigella flexneri 2a or Shigella sonnei diarrhea served as negative controls . Of the 16 paired Thai serum samples tested for immunoglobulin G LPS antibody, 10 had greater than or equal to 4-fold rises (the two subjects with the highest convalescent-phase titers exhibited toxin-neutralizing activity); acute-phase specimens from four of the remaining six individuals already had elevated Shiga LPS titers in their acute specimens ranging from 1:800 to 1:12,800 . Similarly, convalescent-phase sera from the two Israeli patients and the Bangladeshi patient revealed LPS titers of 1:800 to 1:3,200 . In contrast, none of the Maryland volunteers with S . flexneri or S . sonnei diarrhea manifested rises in Shiga anti-LPS (P less than 0.00001 versus 10 of 16 Thai patients) . Only 4 of the 18 Thai patients had significant rise in antibody to purified Shiga toxin, while one of the two Israeli patients and the one Bangladeshi patient had elevated convalescent-phase titers . None of the sera that reacted with Shiga holotoxin had antibody that bound to the peptides . This report, which describes a search for serum antibodies that bind Shiga toxin in patients with Shiga dysentery, demonstrates such antibodies in only a minority of patients with bacteriologically confirmed disease . During Shiga dysentery, Shiga toxin may be elaborated in such small quantities in vivo that it fails to elicit an immune response in most patients even though it may exert biological effects . In this behavior Shiga toxin resembles tetanus toxin, another potent exotoxin that fails to elicit antitoxic responses in people who recover from clinical tetanus. J Infect Dis, 1992 Jul, 166(1), 158 - 61 Age-specific prevalence of serum antibodies to the invasion plasmid and lipopolysaccharide antigens of Shigella species in Chilean and North American populations; Van de Verg LL et al.; Shigella species have virulence plasmids that encode outer membrane proteins (invasion plasmid antigens, Ipa) associated with pathogenicity . Western blots were used to detect antibodies to Ipa in sera from 390 Chilean children, and these responses were compared with those of a US population of infants and adults . Antibodies to lipopolysaccharide (LPS) of Plesiomonas shigelloides and Shigella flexneri 2a were measured by ELISA . Among the Chileans, there was an age-related acquisition of Ipa antibodies, with 28% of 1-year-olds and 100% of children greater than or equal to 10 years showing positive responses . In contrast, none of the US infants and only 38% of the adults had antibodies to Ipa . Levels of LPS antibodies were also found to increase in an age-related manner among the Chileans . These results corroborate findings of previous epidemiologic studies which show that Shigella infections are endemic in Chile, as in other developing countries . The measurement of Ipa and LPS antibodies is a useful seroepidemiologic tool for investigating previous exposure to Shigella species in populations. Kansenshogaku Zasshi, 1992 Jul, 66(7), 930 - 4 {Shigella dysenteriae strains having a provisional serovar isolated from imported diarrheal cases in Tokyo}; Matsushita S et al.; Two bacterial strains (ME448 and ME474) isolated from stool cultures of imported cases in Tokyo in 1987 had typical biochemical characteristics of Shigella dysenteriae . The results of antigenic analyses showed that they were serologically identical to each other, but did not belong to any of the established Shigella serovars . These strains were positive for Sereny test in guinea pig eye and cell-invasion test in HeLa cells . The strains also had virulence-plasmid encoding outer membrane proteins, indicating that they were pathogenic . We then contacted the Centers for Disease Control in the United States and the Central Public Health Laboratory in the United Kingdom and arranged serological examinations of the strain ME448 . From the results, the strain was confirmed to have provisional S . dysenteriae serovar E23507 . Although the serovar had been isolated from a Swedish patient who developed diarrhea while in India, this is thought to be the first report of its isolation in Japan. Eur J Pediatr, 1992 Jul, 151(7), 499 - 501 Plesiomonas shigelloides sepsis and meningoencephalitis in a neonate; Terpeluk C et al.; A newborn infant is described who presented with septicaemia and meningoencephalitis caused by Plesiomonas shigelloides, a Gram-negative rod belonging to the family Vibrionaceae . The patient in this case, the first to be documented in Europe, developed multilocular lysis of the brain despite immediate treatment with antibiotics active in vitro . A cranial CT revealed garland-like calcifications and a large amount of medullary necrosis was seen on MRI. Roum Arch Microbiol Immunol, 1992 Jul-Sep, 51(3), 183 - 91 Study of strains agglutinable with enteroinvasive anti E . coli polyvalent sera isolated from ill and healthy subjects for optimizing the laboratory diagnosis of diarrhoea; Tonciu M et al.; 369 E . coli strains that are agglutinated in A or B anti E . coli enteroinvasive (EIEC) polyvalent sera and inducing no keratoconjunctivitis in the guinea pig's eye have been selected . The biochemical reactions of E . coli strains that can be agglutinated in A or B EIEC polyvalent sera occupy an intermediary position between those of Shigella genus and the classical features of Escherichia, i.e.; 87% are motile bacteria, 88%--ferment lactose, 81% form acid from sodium mucate and lysine is not decarboxylated by 87% of the strains . As for the antigenic behaviour with 15 out of the 16 sera employed, the strains under consideration have agglutinated by slide test in one or several sera, with varying intensities . None of the strains agglutinated on slide in the O164 antiserum . Subsequently, agglutinations have been performed in tubes only with the strains that agglutinated on the slide with a +3 or +4 intensity . Out of the 369 strains under consideration only 25 have agglutinated in the tube, all the false positive reactions representing 6.7% . The data presented lead to the conclusion that such strains that have been isolated from ill or healthy patients cannot be considered as pathogenic diarrhoea agents, the differentiation from the invasive strains (in the absence of the guinea pig for the pathogenicity test) cannot be made on the basis of the biochemical reactions, but only by means of a set of monovalent sera and by performing the tube agglutination tests.(ABSTRACT TRUNCATED AT 250 WORDS) MMWR Morb Mortal Wkly Rep, 1992 Jun 26, 41(25), 440 - 2 Shigellosis in child day care centers--Lexington-Fayette County, Kentucky, 1991; AIDA-I et al.; Zentrum fur Molekulare Biologie Heidelberg (ZMBH), GermanyThe adherence mechanisms of enteropathogenic Escherichia coli (EPEC) to epithelial cells are still not understood . To study the molecular basis of the diffuse adherence (DA) phenotype exhibited by diarrhoeagenic E . coli expressing classical EPEC serotypes we investigated strain 2787 (O126:H27) isolated from a case of infantile diarrhoea . A 6.0 kb plasmid-derived DNA fragment mediates the DA phenotype and encodes the 100 kDa adhesin protein AIDA-I (adhesin involved in diffuse adherence) . Sequencing of the entire fragment revealed two open reading frames which encoded proteins of 45 kDa and 132 kDa, respectively . The 132 kDa protein has been identified as an AIDA-I precursor protein . After cleavage of the signal sequence further processing at the C-terminus of the 132 kDa precursor leads to the mature approximately 100 kDa AIDA-I . While the exact function of the cytoplasmic 45 kDa protein is not known, preliminary evidence indicates that it is necessary for the correct maturation of AIDA-I . The AIDA-I precursor exhibits significant homology with the virG(icsA) protein of Shigella flexneri which seems to be involved in the intercellular spread of invasive Shigella organisms. J Clin Microbiol, 1992 Jun, 30(6), 1428 - 31 Molecular epidemiology of trimethoprim-resistant Shigella boydii serotype 2 strains from Bulgaria; Bratoeva MP et al.; In 1990 an increased number of strains of Shigella boydii serotype 2 were isolated from different regions of Bulgaria . Strains were reported as sporadic, although they showed identical phenotypic characteristics, including resistance to ampicillin, carbenicillin, streptomycin, sulfonamide, tetracycline, ticarcillin, and trimethoprim . The objective of this study was to determine the genetic relatedness of the strains and the mechanism of their antimicrobial resistance . Plasmid fingerprinting showed an identical pattern for 23 of 25 of the selected strains . All 25 strains tested transferred their resistances en bloc to an Escherichia coli recipient . Transconjugants contained a 112-kb R plasmid which carried all the resistance genes, including that conferring type I dihydrofolate reductase-mediated trimethoprim resistance (MIC greater than 2,000 micrograms/ml) . Riboprobe analysis showed identical restriction length fragment polymorphisms, suggesting a highly conserved genome . All findings indicate that strains of S . boydii serotype 2 isolated in 1990 from different regions of Bulgaria were highly related genetically and can be considered representatives of a single bacterial clone . The presence of an R plasmid and selection pressure because of the usage of antimicrobial agents, particularly trimethoprim, have likely facilitated the spread of the clone throughout the country. J Med Microbiol, 1992 Jun, 36(6), 403 - 5 Adhesion of Shigella dysenteriae type 1 and Shigella flexneri to guinea-pig colonic epithelial cells in vitro; Guhathakurta B et al.; Adhesion of bacteria to guinea-pig colonic epithelial cells in vitro was inhibited by fucose with all the four strains tested (two of Shigella dysenteriae type 1 and two of S . flexneri) . N-acetyl neuraminic acid and N-acetyl mannosamine also caused inhibition, suggesting a multiplicity of receptors on the epithelial cell . Congo-red binding of the strains correlated with their adhesive ability, whereas haemagglutination of rabbit erythrocytes by the bacteria did not. Pediatrics, 1992 Jun, 89(6 Pt 2), 1189 - 93 Lethal toxic encephalopathy due to childhood shigellosis in a developed country; Goren A et al.; Shigellosis results in considerable morbidity in endemic areas, but mortality is rare in developed countries . All pediatric deaths (n = 15) in Israel following shigellosis in the past 10 years were reviewed . The patients' ages ranged from 5 months to 11 years; there were eight boys and seven girls . Three were institutionalized mentally retarded patients, 11 were healthy children . Twelve had definite clinical signs of brain death within 48 hours of onset of disease . Cause of death in all patients was consistent with toxic encephalopathy . No other systemic complication was implicated as the cause of death except for one case consistent with a "Reye-like" syndrome . Shigella species were as follows: 8 flexneri, 4 sonnei, 1 dysenteriae, and 2 were not identified . Case-control study of these patients vs surviving, hospitalized patients with shigellosis showed similar severity of fever, diarrhea, vomiting, and dehydration and similar incidence of convulsions . Headache was a prominent feature of patients who died; 5 of 7 verbal patients complained of this symptom as opposed to 2 of 20 in the control group (P less than .01) . There were no significant differences in the hematological and biochemical profile (except for an increased incidence of hyponatremia in the study group), pattern of shigella species, or antibiotic sensitivity . These findings indicate that mortality from shigellosis in a developed country is due primarily to the toxic encephalopathy syndrome. Infect Immun, 1992 Jun, 60(6), 2229 - 36 Novel invasion determinant of enteropathogenic Escherichia coli plasmid pLV501 encodes the ability to invade intestinal epithelial cells and HEp-2 cells; Fletcher JN et al.; An Escherichia coli K-12 transformant carrying 96.5-kb plasmid pLV501 from enteropathogenic E . coli (EPEC) strain K798 is able to produce the same characteristic attaching-effacing lesions in a rabbit ileal biopsy explant model as its parent strain . Cloned EcoRI-SalI DNA restriction fragments from this plasmid failed to reproduce the attaching-effacing lesions, but one recombinant plasmid, pLV527, containing 4.5 kb of pLV501 DNA, conferred on E . coli DH1 transformants the ability to invade enterocytes in the rabbit explant model . DH1(pLV527) was also able to adhere to and invade HEp-2 cells . The relative invasive ability of DH1(pLV527) was quantified by recovery of internalized bacteria following gentamicin treatment of infected HEp-2 monolayers . DH1(pLV527) was 1,000-fold more invasive than DH1 carrying pBR322 or a recombinant plasmid which had no physiological effect on ileal biopsy explants but was less invasive than an enteroinvasive E . coli strain or a transformant carrying the cloned invasion genes of Shigella flexneri . Invasion by DH1(pLV501) could also be detected but occurred at a level 30 times lower than that by DH1(pLV527) . Colony-hybridization of the pLV527 insert against a panel of 49 EPEC and related strains revealed that only 11 contained pLV527-hybridizing sequences; thus, the invasion determinant is not an essential component of the attachment-effacement pathogenic mechanism . One pLV527-hybridizing strain displayed both attachment-effacement and invasiveness in the rabbit ileal biopsy explant model . No significant hybridization was observed to non-EPEC invasive pathogenic enteric bacteria, indicating that the invasion determinant encoded on pLV527 is distinct from those used by these organisms. Infect Immun, 1992 Jun, 60(6), 2218 - 24 Safety, immunogenicity, and efficacy in monkeys and humans of invasive Escherichia coli K-12 hybrid vaccine candidates expressing Shigella flexneri 2a somatic antigen; Kotloff KL et al.; A live, oral Shigella vaccine, constructed by transfer of the 140-MDa invasiveness plasmid from Shigella flexneri 5 and the chromosomal genes encoding the group- and type-specific O antigen of S . flexneri 2a to Escherichia coli K-12, was tested in humans . Designated EcSf2a-1, this vaccine produced adverse reactions (fever, diarrhea, or dysentery) in 4 (31%) of 13 subjects who ingested a single dose of 1.0 x 10(9) CFU, while at better-tolerated doses (5.0 x 10(6) to 5.0 x 10(7) CFU), it provided no significant protection against challenge with S . flexneri 2a . A further-attenuated aroD mutant derivative, EcSf2a-2, was then tested . Rhesus monkeys that received EcSf2a-2 in three oral doses of ca . 1.5 x 10(11) CFU experienced no increase in gastrointestinal symptoms compared with a control group that received an E . coli K-12 placebo . Compared with controls, the vaccinated monkeys were protected against shigellosis after challenge with S . flexneri 2a (60% efficacy; P = 0.001) . In humans, EcSf2a-2 was well tolerated at inocula ranging from 5.0 x 10(6) to 2.1 x 10(9) CFU . However, after a single dose of 2.5 x 10(9) CFU, 4 (17%) of 23 subjects experienced adverse reactions, including fever (3 subjects) and diarrhea (209 ml) (1 subject), and after a single dose of 1.8 x 10(10) CFU, 2 of 4 subjects developed dysentery . Recipients of three doses of 1.2 to 2.5 x 10(9) CFU had significant rises in serum antibody to lipopolysaccharide (61%) and invasiveness plasmid antigens (44%) and in gut-derived immunoglobulin A antibody-secreting cells specific for lipopolysaccharide (100%) and invasiveness plasmid antigens (60%) . Despite its immunogenicity, the vaccine conferred only 36% protection against illness (fever, diarrhea, or dysentery) induced by experimental challenge (P = 0.17) . These findings illustrate the use of an epithelial cell-invasive E . coli strain as a carrier for Shigella antigens . Future studies must explore dosing regimens that might optimize the protective effects of the vaccine while eliminating adverse clinical reactions. Mol Microbiol, 1992 Jun, 6(12), 1605 - 16 icsB: a Shigella flexneri virulence gene necessary for the lysis of protrusions during intercellular spread; Allaoui A et al.; Shigella flexneri causes bacillary dysentery by invading epithelial cells of the colonic mucosa . We have characterized the icsB gene which is located on the virulence plasmid pWR100 . After inactivation of icsB, the mutant strain remained invasive, but formed abnormally small plaques on HeLa cell monolayers, colonized only the peripheral cells of Caco-2 islets, and was unable to provoke a keratoconjunctivitis in guinea-pigs . Examination of infected HeLa cells showed that the icsB mutant was able to lyse the phagocytic vacuole and to form protrusions at the surface of infected cells, but, unlike the wild type, remained trapped in protrusions surrounded by two membranes . These results indicate that IcsB is involved in the lysis of the protrusions, a step necessary for intercellular spread. Microb Pathog, 1992 Jun, 12(6), 399 - 407 Induction of a humoral immune response to a Shiga toxin B subunit epitope expressed as a chimeric LamB protein in a Shigella flexneri live vaccine strain; Ryd M et al.; Shigella flexneri vaccine strain (SFL124) given orally, evokes humoral immune response in human volunteers . Such a strain, expressing antigenic epitope of B subunit of Shiga toxin, would also provide immunity to the toxin produced by some species of Shigella . A synthetic oligonucleotide, specifying an epitope {13-26 amino acids (aa)} of the B subunit of Shiga toxin, was inserted into the lamB gene of Escherichia coli and expressed in the S . flexneri vaccine strain . The chimeric LamB protein functioned normally and the epitope was expressed at the surface of the bacteria . The animals immunized with the live bacteria, expressing the epitope or sonicated lysates, showed a humoral response that was specific to the peptide (13-26 aa) and to the whole B subunit molecule . The elicited antisera neutralized the toxin activity on HeLa cells up to 40%, while the purified IgG fractions from the sera gave 90% neutralization. Int J Epidemiol, 1992 Jun, 21(3), 594 - 8 Molecular probe analysis of Shigella dysenteriae type 1 isolates from 1940 to 1987; Blaser MJ et al.; Fourteen strains of Shigella dysenteriae type 1 (Shiga bacillus) isolated from people in diverse locations from 1940 to 1987 were studied . Southern hybridization with three cloned Escherichia coli genes, Shiga-like toxin I (SLTI), frd, and ompF, was used to determine restriction fragment length polymorphism (RFLP) of the genomic DNA of these strains . Digestion with each of four restriction endonucleases generated fragments of identical size to which the frd and ompF hybridized for each of the 14 strains, indicating the conservation of these genes and their flanking sequences . In contrast, after digestion with HindIII, EcoRV, and ClaI and probing with SLTI, there were RFLP among the strains . The results showed three clones of the Shiga bacillus, and suggested that dissemination of a single clone may continue for decades within a wide geographical area. Lab Anim Sci, 1992 Jun, 42(3), 240 - 4 Enrofloxacin treatment of long-tailed macaques with acute bacillary dysentery due to multiresistant Shigella flexneri IV; Line AS et al.; Thirty-four cases of acute bacillary dysentery occurred within 90 days among macaques housed at the California Regional Primate Research Center . Cases were identified by depression, diarrhea with blood and leukocytic exudate, and/or leukocytosis with a left shift . Antimicrobial susceptibility testing of enteric isolates and plasmid profile analyses established an etiologic diagnosis of multiple antibiotic resistant Shigella flexneri IV infection . When standard therapies were invalidated by high frequencies of resistance among the isolates, therapy with enrofloxacin, a fluoroquinolone antimicrobial, was initiated to interrupt the epidemic . Serum concentrations of enrofloxacin and its primary metabolite ciprofloxacin were measured in selected cases . A serum concentration-time data analysis was performed to evaluate the oral enrofloxacin dose and dosing interval for nonfasted macaques . Once daily administration of 5 mg/kg enrofloxacin by gastric intubation produced 24-hour serum concentrations above the MICs for the Shigella isolates from this outbreak. Carbohydr Res, 1992 May 14, 229(1), 103 - 16 Stereoselective syntheses of a di-, tri-, and tetra-saccharide fragment of Shigella dysenteriae type 1 O-antigen using 3,4,6-tri-O-acetyl-2-azido-2-deoxy-alpha-D-glucopyranosyl chloride as a glycosyl donor; Pavliak V et al.; Methyl 2,4-di-O-benzoyl-alpha-L-rhamnopyranoside (1) furnished a crystalline 3-O-bromoacetyl derivative that was treated with the dichloromethyl methyl ether-ZnCl2 reagent to give 2,4-di-O-benzoyl-3-O-bromoacetyl-alpha-L-rhamnopyranosyl chloride (3) . Compounds 1 and 3 were condensed under the conditions of base-deficient, silver trifluoromethanesulfonate-mediated glycosylation to give a fully protected rhamnobioside, which on O-debromoacetylation afforded the disaccharide nucleophile 10 . Similar condensation of 3 with methyl 3-O-benzoyl-4,6-O-benzylidene-alpha-D-galactopyranoside, followed by O-debromoacetylation and condensation of the thus formed methyl O-(2,4-di-O-benzoyl-alpha-L-rhamnopyranosyl)-(1----2)-4,6-O-benzylidene- 3-O-benzoyl-alpha-D-galactopyranoside again with 3, gave the trisaccharide glycoside . Subsequent O-debromoacetylation gave 17, having only HO-3(3) unsubstituted . Silver perchlorate-mediated glycosylations of 1, 10, and 17 with 3,4,6-tri-O-acetyl-2-azido-2-deoxy-alpha-D-glucopyranosyl chloride afforded, with high alpha stereoselectivity, protected di-, tri-, and tetra-saccharide glycosides . Subsequent hydrogenation, followed by N-acetylation and O-deacylation, afforded three oligosaccharide glycosides having nonreducing terminal 2-acetamido-2-deoxy-alpha-D-glucopyranosyl residues and comprising successively larger portions of the repeating unit of Shigella dysenteriae type 1 O-antigen. FEMS Microbiol Lett, 1992 May 1, 71(3), 217 - 21 Virulence phenotypes of Shigella flexneri 2a avirulent mutant 24570 can be complemented by the plasmid-coded positive regulator virF gene; Qi MS et al.; Avirulent mutation of an opaque colony variant of Shigella flexneri 2a designated 24570 has been believed to be linked with the glpK locus of the chromosome . However, avirulent phenotypes of the 24570 strain could be complemented by the invasion plasmid-coded virF gene, a positive regulator for invasion genes . The 24570 strain had a DNA structural alteration upstream of the virF gene. Diagn Microbiol Infect Dis, 1992 May-Jun, 15(4), 359 - 61 Fluorescent antibody staining test for rapid diagnosis of Shigella dysenteriae 1 infection; Albert MJ et al.; An indirect fluorescent antibody test for rapid detection of Shigella dysenteriae 1 in diarrheal stools was developed . A diagnosis could be made within 90 min of submission of specimens to the laboratory . On comparison with culture results, the test had a sensitivity of 92%, a specificity of 93%, and positive and negative predictive values of 94% and 92%, respectively. Clin Infect Dis, 1992 May, 14(5), 1055 - 60 Antimicrobial resistance of Shigella isolates in Bangladesh, 1983-1990: increasing frequency of strains multiply resistant to ampicillin, trimethoprim-sulfamethoxazole, and nalidixic acid; Bennish ML et al.; The susceptibility to ampicillin and trimethoprim-sulfamethoxazole (TMP-SMZ) was determined for 15,824 isolates of Shigella obtained from patients attending a treatment center in Dhaka, Bangladesh, from 1983 through 1990 and for 520 isolates obtained during community surveys from 1988 through 1990 . Susceptibility to nalidixic acid was determined for isolates obtained after 1985 . In 1983 13% of isolates were resistant to ampicillin, 23.5% to TMP-SMZ, and 0.8% to both drugs . By 1990 51.2% of isolates obtained at the Diarrhea Treatment Centre were resistant to ampicillin, 47.7% to TMP-SMZ, and 40.5% to both drugs (for comparison with figures for 1983, P less than .001) . Resistance to nalidixic acid increased from 0.8% in 1986 to 20.2% in 1990 (P less than .001) . In 1990 71.5% of