Identification and distribution of Flavobacterium meningosepticum in clinical material

During the 19 year period ending December 1984, 82 (1.7%) of 4840 strains of Gram-negative non-fermentative bacteria submitted to the National Collection of Type Cultures (NCTC) for computer-assisted identification were Flavobacterium meningosepticum. These figures suggest either that F. meningosepticum occurs only rarely in clinical material in the UK, or that when it does occur it is not always recognized. The sources from which the NCTC strains were isolated are reported and also the characteristics by which the species may be identified. The clinical significance of F. meningosepticum is reviewed, particularly its role in neonatal meningitis, of which there have been but two reported cases in the UK, both imported. The susceptibility of the species to antimicrobial agents is discussed and also antimicrobial therapy of neonatal meningitis due to this species.     

Identification and distribution of Flavobacterium meningosepticum in clinical material

During the 19 year period ending December 1984, 82 (1.7%) of 4840 strains of Gram-negative non-fermentative bacteria submitted to the National Collection of Type Cultures (NCTC) for computer-assisted identification were Flavobacterium meningosepticum. These figures suggest either that F. meningosepticum occurs only rarely in clinical material in the UK, or that when it does occur it is not always recognized. The sources from which the NCTC strains were isolated are reported and also the characteristics by which the species may be identified. The clinical significance of F. meningosepticum is reviewed, particularly its role in neonatal meningitis, of which there have been but two reported cases in the UK, both imported. The susceptibility of the species to antimicrobial agents is discussed and also antimicrobial therapy of neonatal meningitis due to this species.     

Streptomycetes possess peptidyl-prolyl cis-trans isomerases that strongly resemble cyclophilins from eukaryotic organisms

A functionally active 17.5 kDa peptidyl-prolyl cis-trans isomerase was purified to homogeneity from Streptomyces chrysomallus, a Gram-positive filamentous bacterium. Characterization of the enzyme revealed inhibition and binding characteristics, against the immunsuppressive drug cyclosporin A, which were similar to cyclophilins from eukaryotes such as mammals, plants, fungi and yeasts, but different from those of cyclophilins from enterobacteria such as Escherichia coli. The amino acid sequence of the S. chrysomallus cyclophilin, as deduced from the gene sequence, revealed a striking degree of amino acid sequence identity with the corresponding 17 kDa proteins of humans (66%), Neurospora (70%) and yeast (69%). Comparison with cyclophilin sequences from the Gram-negative enterobacteria revealed much less homology (25% identity with E. coli b, 23% identity with E. coli a). Cyclophilin was detected in each of the four other Streptomyces species tested. The cyclophilins from the various streptomycetes differed in size, varying between 17 and 20.5 kDa. The cyclophilins were abundant in the Streptomyces cells, and present throughout growth.     

美罗培南对1139株革兰阴性杆菌抗菌活性研究

目的分析美罗培南对革兰阴性杆菌的抗菌活性,为临床合理使用美罗培南提供正确依据。方法将宁波市第一医院2004年6月至2005年8月的临床各种标本分离获得的革兰阴性杆菌在VITEK-32微生物自动鉴定分析仪中进行鉴定和药敏试验。用双纸片法及2-巯基丙酸抑制试验进行ESBLs、AmpC和金属酶的检测。结果共检出临床常见的革兰阴性杆菌1139株,其中肠杆菌科559株（大肠埃希菌309株,肺炎克雷伯菌186株,阴沟肠杆菌64株）,非发酵菌580株（铜绿假单胞菌227株,嗜麦芽窄食单胞菌72株,脑膜脓毒黄杆菌44株．鲍曼不动杆菌178株．洋葱伯克霍尔德菌30株,荧光假单胞菌29株）。美罗培南对大肠埃希菌、肺炎克雷伯菌、阴沟肠杆菌、铜绿假单胞菌、鲍曼不动杆菌、嗜麦芽窄食单胞菌、脑膜脓毒黄杆菌、荧光假单胞菌的耐药率分别为0．0％、0．0％、0．0％、22．9％、23．6％、90．3％、100．0、63．3％和3．4％。结论美罗培南对革兰阴性杆菌有很强的抗菌活性,其抗菌活性要强于亚胺培南,是目前治疗肠杆菌科细菌特别是产ESBLs、AmpC酶细菌感染的危重患者的最理想用药。美罗培南耐药率呈逐年增加趋势,应引起重视。美罗培南对嗜麦芽窄食单胞菌、脑膜脓毒黄杆菌、洋葱伯克霍尔德菌活性很低,临床对于上述细菌感染不应选用美罗培南。     

Microbiological quality of water and dialysate in a haemodialysis unit in Ponta Grossa-PR, Brazil

AIMS: The objective of the study was to determine the microbiological quality of samples of water and dialysate in a haemodialysis unit. METHODS AND RESULTS: Seventy-two samples each of water and dialysate were collected during November 2003 to April 2004. The following microbiological analyses were performed: test for total and faecal coliforms, which produced negative results for all the samples; counts of total heterotrophic bacteria, where three samples of water and two of dialysate showed levels higher than those permitted by national standards; and endotoxin assay, which revealed high quantities only in samples of water that preceded reverse osmosis. Nonfermenting Gram-negative bacteria were identified in 54 samples of dialysate and in 26 samples of water. The test for adhesion to an inert surface showed that various bacteria were capable of forming biofilms. Twenty-seven per cent of the bacteria were resistant to sodium hypochlorite at 500 ppm for 10-min contact time. Sixty per cent of the isolates were resistant to three or more antibiotics. CONCLUSIONS: Water and dialysate can be a source of infection for patients who need haemodialysis. SIGNIFICANCE AND IMPACT OF THE STUDY: An adequate system for water treatment, disinfection of the haemodialysis system and microbiological monitoring of the water and dialysate are necessary to reduce bacteraemia and pyrogenia outbreaks.     

Characteristics of enterobacteria isolated from patients with urogenital pathology

Species composition and a number of persistence characteristics enterobacteria isolated from urine of 42 pregnant and 22 nonpregnant women with pyelonephritis (relapse, remission), from prostatic fluid of 225 males and secretions of cervical canal of 124 women with urogenital pathology (prostatitis, salpingo-oophoritis) were studied. The study revealed that enterobacteria, including Escherichia coli, prevailed in the structure of uromicroflora (66.7-83.3%) and constituted a relatively small proportion among "genital" isolates of microorganisms (19.9-22.2%). Male and female sterility and the presence of enterobacteria in the reproductive tract of patients were found to be directly correlated. Clinical isolates of enterobacteria were shown to possess pronounced seroresistance and the complex of persistence characteristics, including antilysozyme, anti-intercidal and anticomplementary activity.     

Etiotropic antibiotic therapy and immunotherapy of patients with pyo-inflammatory processes]

A 3-year experience was reviewed in the treatment of patients with pyoinflammatory processes (PIP) which developed during the postoperative period in 387 persons with closed injury and multiple penetrating wounds of the chest and stomach complicated by massive hemorrhage. When the PIP was localized in the abdominal cavity, enterobacteria and bacteroides were the main pathogens: 49.4 +/- 2.1 and 32.8 +/- 1.4 per cent, respectively. When the PIP was localized in the thoracic cavity, the most frequent pathogens were staphylococci, Pseudomonas aeruginosa, and enterobacteria: 26.5 +/- 1.4, 24.6 +/- 1.4 and 13.3 +/- 0.8 per cent, respectively. In all the cases high variability of the antibiotic susceptibility of the isolates and predominance of the strains resistant to 5 or more drugs were observed. A suppressive effect of thienam on the immune system was revealed. The immunocorrection in parallel with the antibiotic therapy made it possible to prevent further development of immune deficiency and to recover the bactericidal potency of the phagocyting cells. The use of various physiochemical methods in complex treatment of PIPs is substantiated.     

Enterobacteria and Pseudomonas aeruginosa in the etiology of chronic lung and pleural diseases

The isolation rate of P. aeruginosa and enterobacteria from washed sputa and tracheobronchial exclude obtained from patients with pulmonary and pleural diseases varies within 54.9-56.9 +/- 6.9%. In most cases microorganisms have been isolated as monoculture from pleural fluid, including P. aeruginosa, the main etiological agent in pleural diseases, isolated in 65.4 +/- 10.6% of cases.     

Evidence of septic system failure determined by a bacterial biochemical fingerprinting method

AIMS: To provide evidence of septic system failure by comparing two faecal indicator bacteria, enterococci and Escherichia coli, from defective septic tanks and adjacent creeks. METHODS AND RESULTS: A biochemical fingerprinting method was used to type and compare enterococci and E. coli strains from 39 septic tanks with creek water samples. Phenotypic diversity of enterococci (0.5 +/- 0.3) and E. coli (0.5 +/- 0.3) in septic tanks were significantly lower than those found in water samples (0.8 +/- 0.1, P < 0.0001 for enterococci and 0.9 +/- 0.1, P < 0.0001 for E. coli). Among 1072 enterococci isolates tested from septic tanks, 203 biochemical phenotypes (BPTs) were found of which 98 BPTs from 33 septic tanks were identical to several water samples. Similarly, among 621 E. coli isolates tested from septic tanks, 159 BPTs were found of which 53 BPTs from 26 septic tanks were also identical to water samples. The number of the latter bacteria was significantly (P = 0.01) higher in water samples collected from downstream compared with that of upstream in the study area. A high similarity between the populations of both indicator bacteria was also found between defective septic tanks and downstream water samples further indicating the contamination of both creeks by defective septic systems. CONCLUSIONS: Biochemical fingerprinting of faecal indicator bacteria is a useful and rapid method to provide direct evidence for septic system failure. Combination of both faecal indicator bacteria (enterococci and E. coli) provides a better judgement of the performance of a septic system. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first to provide direct evidence of septic system failure by identifying the presence of specific bacterial types in septic tanks and surface waters. Based on our findings, we suggest that the performance evaluation of a septic system should be accompanied by direct analysis of faecal indicator bacteria.     

Occurrence of fungi in water used at a haemodialysis centre

Aims: The aim of this study was to identify and determine the diversity, occurrence and distribution of fungi in water used at a haemodialysis centre. Methods and Results: Samples in the hydraulic circuit for the distribution of the water, dialysate samples and samples of sterilization solution from dialysers were collected over a 3‐month period, and 500 ml of each sample was filtered through membranes. All together 116 isolates of fungi were recovered from 89% of all water samples collected inside the haemodialysis unit, with prevalence of moulds in tap water samples and of yeasts in dialysate samples. Fusarium spp. was the most abundant genus found, whereas Candida parapsilosis was the predominant yeast species. Conclusions: This study demonstrated that various fungi were present in the water system. These data suggest the inclusion of the detection and quantification of fungi in the water of haemodialysis. Significance and Impact of the Study: The recovery of fungi from aqueous haemodialysis environments implies a potential risk for haemodialysis patients and indicates the need for continuous maintenance and monitoring. Further studies on fungi in haemodialysis water systems are required to investigate the organism ability to persist, their role in biofilm formation and their clinical significance.     

Etiology of purulent septic diseases and the antibiotic resistance of the isolated causative agents

Among the causative agents of purulent septic diseases in the surgical hospital, 25 microbial species were isolated; of these, the prevailing species were Staphylococcus aureus (19.86 +/- 1.07%), Escherichia coli (16.5 +/- 0.99%) and Pseudomonas aeruginosa (10.06 +/- 0.8%). From environmental objects in the hospital 14 microbial species were isolated, among them bacteria of the genus Enterobacter (27 +/- 1.7%), E. coli (19.07 +/- 1.48%), S. aureus (14.7 +/- 1.31%), Klebsiella pneumoniae (13.73 +/- 1.31%), P. aeruginosa (7.33 +/- 0.98%). During 3 years of observation the isolation rate of K. pneumoniae from different environmental objects was found to increase threefold to 24.7 +/- 2.7%. The results of the study of the microbial picture in surgical hospitals, as well as the antibiotic resistance of circulating causative agents, should be borne in mind while taking epidemic control measures.     

The occurrence of Pseudomonas spp. in surface water and in tap water as determined on citrate media

Citrate-utilizing bacteria were counted in 289 samples of tap water derived from either surface water or ground water and in 32 samples of raw or partially treated surface water by using media containing ferric ammonium citrate as the carbon and energy source.The citrate-utilizing bacteria constituted only small minorities of the colony counts on Lab-Lemco agar at 25 C in both tap water and surface water.A total of 1071 isolates were obtained, of which 979 were able to utilize citrate. Characterization of the citrate-utilizing isolates revealed that 90% of these bacteria were arginine dihydrolase-positive and belonged to the genera Pseudomonas (84.3%) and Aeromonas (5.7%).The genus Pseudomonas was represented by fluorescent pseudomonads (66.3%), non-fluorescent glucose-utilizing pseudomonads (12.1%) and P. alcaligenes (5.9%). None of the isolates was identified as P. aeruginosa.It is suggested that the pseudomonads and the aeromonads are not adapted to low substrate concentrations. Enumeration of the citrate-utilizing bacteria in tap water therefore may give information on the efficiency of water treatment techniques as regards the substrate removal.     

The role of aminoglycoside--modifying enzymes in resistance of Gram-negative rods

The aim of the study was to evaluate the aminoglycoside resistance of Gram-negative bacilli isolated from patients. To the examination 35 strains of Enterobacteriaceae and 18 of non-fermentative bacteria were included. Resistance to aminoglycosides (gentamicin (G), netilmicin (Nt), tobramycin (T), amikacin (A), kanamycin (K), neomycin (N)) was established by disk diffusion method. Interpretation of enzymatic mechanisms was performed by Livermore. The most common enzymes AAC(6')I were found in Enterobacteriaceae group (mostly in E. cloaceae and P. mirabilis) and AAC(3') and in non-fermentative bacteria: AAC(6')I in P. aeruginosa and APH(3')VI and AAC(3')I in A. baumanii. The most frequent phenotype was resistance to six antibiotics (G, Nt, T, A, K, N) Resistance rates were high for gentamicin (>70 %) in both groups and amikacin (88,89 %) in non-fermentatives.     

Antimicrobial susceptibility and molecular mechanisms of resistance to beta-lactams of gram-negative microorganisms--causative agents of nosocomial infections

Profiles and mechanisms of resistance to beta-lactam antibiotics of isolates of Gram-negative microorganisms, which are causative agents of infections in Intensive Care Unit of hospital surgery department, were studied. Two hundred and ten clinical isolates were studied: Pseudomonas aeruginosa--86 strains (40.9%), Acinetobacter baummanii--45 strains (21.4%), Klebsiella pneumoniae--52 strains (24.8%), Escherichia coli--23 strains (11%), Enterobacter spp.--4 strains (1.9%). Profiles of antibiotic resistance were studied by the method of serial microdilutions; detection of most widespread and clinically significant genes of beta-lactamases of Gram-negative bacteria was performed by polymerase chain reaction. Carbapenems and cefoperazone/sulbactam were the most active antibiotics. Local features of distribution of beta-lactamase coding genes (TEM, SHV, CTX) in K. pneumoniae and E. coli isolates were revealed. Eleven strains of P. aeruginosa resistant to carbapenems and possessing genetic determinants of VIM-group, which codes metallo-beta-lactamases, were isolated. Obtained data allows to assess the parameters of resistance to beta-lactam antibiotics and to reveal the main mechanisms of such resistance in etiologic agents of nosocomial infections, that, in its turn, allows to choose preparations for etiotropic therapy.     

Human-associated extended-spectrum β-lactamase in the Antarctic

Escherichia coli bacteria with extended-spectrum β-lactamase (ESBL) type CTX-M resistance were isolated from water samples collected close to research stations in Antarctica. The isolates had bla(CTX-M-1) and bla(CTX-M-15) genotypes and sequence types (ST) indicative of a human-associated origin. This is the first record of ESBL-producing enterobacteria from Antarctica.     

革兰阴性杆菌对头孢哌酮／舒巴坦耐药率的变迁

目的调查革兰阴性杆菌对头孢哌酮／舒巴坦的耐药率变化。方法收集2004年1月至2007年12月从我院住院患者各种临床标本中分离的革兰阴性杆菌,使用VITEK-60全自动微生物分析仪进行菌种的鉴定,采用K-B法对头孢哌酮／舒巴坦进行药敏试验,对结果进行回顾性凋查。结果肠杆菌科细菌对头孢哌酮／舒巴坦的耐药率较低,大肠埃希菌、肺炎克雷伯菌和阴沟肠杆菌对头孢哌酮／舒巴坦的耐药率分别为1．7％,7．7％和5．8％。嗜麦芽窄食假单胞菌、洋葱伯克霍尔德菌、脑膜脓毒性金黄杆菌、铜绿假单胞菌和鲍曼不动杆菌对头孢哌酮／舒巴坦的耐药率分别为27．6％、38．0％、2．3％、23．5％和4．8％。铜绿假单胞菌和鲍曼不动杆菌对头孢哌酮／舒巴坦的耐药率从2004年的35．1％和23．7％下降至2007年的12．4％和0．4％。结论头孢哌酮／舒巴坦对肠杆菌科细菌具有非常强的体外抗菌活性,铜绿假单胞菌和鲍曼不动杆菌对头孢哌酮／舒巴坦的耐药率呈下降趋势。     

Prevalence and clonal nature of Escherichia coli O157:H7 on dairy farms in Wisconsin.

A survey was conducted between March and October of 1994 to determine the prevalence and identify the sources of serotype O157:H7 isolates of Escherichia coli in Wisconsin dairy herds. A stratified sample of 400 farms was identified, and 70 farms with weaned calves less than 4 months old were included in the study. During the prevalence study, 5 of the 70 farms (herd prevalence, 7.1 +/- 4.5%) and fecal samples from 10 of 560 calves (animal prevalence, 1.8%) tested positive for serotype O157:H7. In a follow-up study, the five O157:H7-positive farms and seven of the O157:H7-negative farms identified in the prevalence study were visited again. An additional 517 fecal samples from cattle of various ages were tested, and a total of 15 animals from four of the five herds that were previously positive and 4 animals from two of seven herds that were previously negative tested positive for E. coli O157:H7. Observations made during the follow-up study suggested that horizontal transmission was an important means of E. coli O157:H7 dissemination on the farms. A total of 302 environmental samples, were examined, and 2 animal drinking water samples from one previously negative farm and 1 animal drinking water sample from a previously positive farm contained E. coli O157:H7. Analyses by the pulsed-field gel electrophoresis technique of contour-clamped homogeneous electric field electrophoresis revealed that isolates from the same farm displayed identical or very similar XbaI restriction endonuclease digestion profiles (REDP), whereas isolates from different farms typically displayed different REDP. However, more than one REDP was usually observed for a given herd over the 8-month sampling period. Analyses of multiple isolates from an animal revealed that some animals harbored O157:H7 strains that had different REDP, although the REDP of isolates obtained from the same fecal sample were very similar. Collectively, 160 bovine isolates obtained from 29 different animals and three water isolates displayed 20 distinct XbaI REDP. Our data revealed that there are several clonal types of serotype O157:H7 isolates in Wisconsin and indicated that there is probably more than one source of this pathogen on the dairy farms studied. However, animal drinking water was identified as one source of E. coli O157:H7 on one farm.     

2007年至2009年3种非发酵革兰阴性杆菌耐药性分析

目的研究自临床分离的铜绿假单胞菌、鲍曼不动杆菌、嗜麦芽寡养单胞菌等3种非发酵革兰阴性杆菌的耐药性及其变迁,为合理使用抗菌药物提供依据。方法临床标本按常规方法分离培养,用生物梅里埃API分析系统鉴定细菌种类,根据CLSI规定的标准,采用纸片扩散法进行体外药敏测定,WHONET软件进行统计分析。结果 2007年至2009年共分离到铜绿假单胞菌310株、鲍曼不动杆菌280株和嗜麦芽寡养单胞菌86株。其中亚胺培南不敏感的铜绿假单胞菌为32.5%,亚胺培南不敏感的铜绿假单胞菌对其他药物的耐药率也明显高于亚胺培南敏感菌株;鲍曼不动杆菌对大部分抗生素的耐药率都高于60%,对亚胺培南、美罗培南3年总的敏感率为51.6%和48.2%;嗜麦芽寡养单胞菌对米诺环素的敏感率为93.8%。比较3年耐药率的变迁,2009年部分抗菌药物耐药性增长的势头得到遏制。结论非发酵菌是引起院内感染的重要病原菌,对多种抗菌药物都有较高的耐药性,合理使用抗生素,加强医院感染的控制对减少细菌耐药性的产生有非常重要的作用。     

Long-term intake of egg white hydrolysate attenuates the development of hypertension in spontaneously hypertensive rats

This paper evaluates the effect of the long-term intake of a hydrolysate of egg white with pepsin (HEW), with a potent angiotensin converting enzyme inhibitory activity, on the development of hypertension of spontaneously hypertensive rats (SHR). After being weaned, male 3-week-old SHR were randomly divided into five groups that were given until the 20th week of life the following drinking fluids: (1) tap water, (2) non-treated egg white 1 g/kg/day, (3) captopril 100 mg/kg/day, (4) HEW 0.5 g/kg/day, and (5) HEW 1 g/kg/day. From the 20th to 25th week of life, animals from all groups were given tap water. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured weekly in the rats, from the 6th to 25th week of life, by the tail cuff method. Development of hypertension was attenuated in the groups treated with captopril and HEW (P<0.001 vs. the group that drunk tap water). At the 20th week of life, the arterial blood pressure values of the different groups of rats were: tap water (SBP = 219.5 +/- 5.7, DBP = 167 +/- 3.7), non-treated egg white (SBP = 206.4 +/- 1.43, DBP = 166.4 +/- 4.9), captopril (SBP = 131.7 +/- 2.74, DBP = 91.5 +/- 1.62), HEW 0.5 g/kg/day (SBP = 182.9 +/- 4.64, DBP = 127.5 +/- 2.1) and HEW 1 g/kg/day (SBP = 177.7 +/- 4.72, DBP = 120.1 +/- 2.4). SBP and DBP increased in the treated SHR when the corresponding antihypertensive treatment was removed. In spite of this, SBP remained lower in the SHR that had received captopril and HEW than in the SHR of the control groups (P<0.05). The present results suggest that HEW could be used as a functional food with antihypertensive activity.     

Modifications to United States Environmental Protection Agency methods 1622 and 1623 for detection of Cryptosporidium oocysts and Giardia cysts in water

Collaborative and in-house laboratory trials were conducted to evaluate Cryptosporidium oocyst and Giardia cyst recoveries from source and finished-water samples by utilizing the Filta-Max system and U.S. Environmental Protection Agency (EPA) methods 1622 and 1623. Collaborative trials with the Filta-Max system were conducted in accordance with manufacturer protocols for sample collection and processing. The mean oocyst recovery from seeded, filtered tap water was 48.4% +/- 11.8%, while the mean cyst recovery was 57.1% +/- 10.9%. Recovery percentages from raw source water samples ranged from 19.5 to 54.5% for oocysts and from 46.7 to 70.0% for cysts. When modifications were made in the elution and concentration steps to streamline the Filta-Max procedure, the mean percentages of recovery from filtered tap water were 40.2% +/- 16.3% for oocysts and 49.4% +/- 12.3% for cysts by the modified procedures, while matrix spike oocyst recovery percentages ranged from 2.1 to 36.5% and cyst recovery percentages ranged from 22.7 to 68.3%. Blinded matrix spike samples were analyzed quarterly as part of voluntary participation in the U.S. EPA protozoan performance evaluation program. A total of 15 blind samples were analyzed by using the Filta-Max system. The mean oocyst recovery percentages was 50.2% +/- 13.8%, while the mean cyst recovery percentages was 41.2% +/- 9.9%. As part of the quality assurance objectives of methods 1622 and 1623, reagent water samples were seeded with a predetermined number of Cryptosporidium oocysts and Giardia cysts. Mean recovery percentages of 45.4% +/- 11.1% and 61.3% +/- 3.8% were obtained for Cryptosporidium oocysts and Giardia cysts, respectively. These studies demonstrated that the Filta-Max system meets the acceptance criteria described in U.S. EPA methods 1622 and 1623.