武汉市牡蛎创伤弧菌污染状况调查分析

创伤弧菌(Vibrio vulnificus)是一种革兰氏阴性嗜盐菌,自然生存于河口和海洋环境中,能引起多种感染,主要临床表现有败血症、伤口感染、急性肠胃炎等,感染致死率可高达50%以上[1-2].创伤弧菌污染是美国海产品消费引起死亡的首要原因,美国州际贝类卫生委员会(ISSC)规定,收获后经处理的牡蛎中创伤弧菌限量不超过30 cfu/g[3].     

Vibrio vulnificus infections: case reports and literature review

This study's purpose was to determine the validity of near-infrared interactance (NIR) and bioelectric impedance (BIA) in tracking changes in body composition over 12 wk of either a high intensity endurance (ET) or resistance (RT) training program in nondieting weight-stable untrained males. Prior to and following the control or training period, each subject completed a series of body composition analyses including hydrostatic weighing (HW) with a measurement of residual volume: anthropometric measurements including height, weight, skinfold, and girth: BIA measurement: and NIR measurements. Based on the HW results, there were no significant body composition changes in the control group. For the ET group, a significant decline in relative body fat resulted from a reduction in fat weight (FW) with no change in fat-free weight (FFW). In the RT group, both a significant decline in FW and an increase in FFW contributed to this group's decline in relative body fat. Tracking changes in relative body fat, FW, and FFW, skinfolds agree reasonably well with HW in all groups while BIA and NIR did not always track body composition changes well. For example, SF and BIA were significantly correlated with the changes in FFW (HW = +4.1%, SF = +4.5%. BIA = +3.1%. NIR = -0.7%) observed in the RT group compared to HW (SF: r-value = 0.45, SEE = 2.5; BIA: r = 0.33, SEE = 3.4) while the NIR measurements were nonsignificant (r = 0.09, SEE = 5.0). Interestingly, NIR underestimated the gain in FFW in the resistance trained group while BIA underestimated the changes in relative body fat. FW, and FFW in the endurance trained group. Based on these results, BIA and NIR appear not to be appropriate measurement tools for tracking body composition changes in endurance and resistance training individuals respectively.     

Characterization of the hemorrhagic reaction caused by Vibrio vulnificus metalloprotease, a member of the thermolysin family

Vibrio vulnificus is an opportunistic human pathogen causing wound infections and septicemia, characterized by hemorrhagic and edematous damage to the skin. This human pathogen secretes a metalloprotease (V. vulnificus protease [VVP]) as an important virulence determinant. When several bacterial metalloproteases including VVP were injected intradermally into dorsal skin, VVP showed the greatest hemorrhagic activity. The level of the in vivo hemorrhagic activity of the bacterial metalloproteases was significantly correlated with that of the in vitro proteolytic activity for the reconstituted basement membrane gel. Of two major basement membrane components (laminin and type IV collagen), only type IV collagen was easily digested by VVP. Additionally, the immunoglobulin G antibody against type IV collagen, but not against laminin, showed sufficient protection against the hemorrhagic reaction caused by VVP. Capillary vessels are known to be stabilized by binding of the basal surface of vascular endothelial cells to the basement membrane. Therefore, specific degradation of type IV collagen may cause destruction of the basement membrane, breakdown of capillary vessels, and leakage of blood components including erythrocytes.     

Activation of particulate guanylyl cyclase by Vibrio vulnificus hemolysin

Recently we reported that Vibrio vulnificus hemolysin, an exotoxin produced by V. vulnificus, dilates rat thoracic aorta via elevated cGMP levels without affecting nitric oxide synthase. We investigated the mechanism further by observing the guanylyl cyclase activities in cytosolic, membrane, unfractionated, or reconstituted preparations. Hemolysin did not activate guanylyl cyclase in the membrane or cytosolic fraction, while it activated guanylyl cyclase in unfractionated or reconstituted preparation. The increased activity was not inhibited by the HS-142-1, a microbial polysaccharide which antagonizes atrial natriuretic peptide receptor, or 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), a soluble guanylyl cyclase inhibitor. However, it was attenuated by 6-(phenylamino)-5,8-quinolinedione (LY 83.583), which inhibits the catalytic domain of both guanylyl cyclases, and by cholesterol, which blocks hemolysin-incorporation into the membrane. Removing ATP, a cofactor of particulate guanylyl cyclase, attenuated the activation and ATPgammaS, a non-phosphorylating analog, restored it. These results suggest that V. vulnificus hemolysin activates particulate guanylyl cyclase via hemolysin incorporation into the vascular smooth muscle cell membrane in cooperation with certain unidentified cytosolic component(s).     

An epimerase gene essential for capsule synthesis in Vibrio vulnificus

The extracellular capsule polysaccharide (CPS) of Vibrio vulnificus is a primary virulence factor which allows survival of the bacteria in the human host. To study the genes involved in expression of the capsule, we generated mutants that lost the ability to produce CPS following the insertion of a minitransposon into the genome of an encapsulated, clinical strain of V. vulnificus. A genomic region, from one nonencapsulated mutant, containing the transposon and flanking V. vulnificus DNA was cloned, and a probe complementary to the chromosomal DNA immediately adjacent to the transposon was used to locate this fragment in the genome of the encapsulated parent strain. The fragment, which contained a putative capsule gene, was cloned and, when supplied in trans, complemented the mutation in the nonencapsulated mutant to restore capsule production. In addition, virulence studies, using the 50% lethal dose assay, showed that the restoration of capsule production also restored the virulence of the organism. Sequence analysis of the gene disrupted by the transposon revealed that it matched a nucleotide-sugar epimerase of Vibrio cholerae O139, with 75 and 85% identities at the nucleotide and amino acid levels, respectively. In addition, computer analysis recognized epimerases of various organisms as highly similar to the putative epimerase of V. vulnificus. Finally, a combination of PCR amplification and Southern blotting showed that this epimerase is common to at least 10 strains of V. vulnificus that each express a serologically distinct CPS. Our results indicate that the epimerase gene is essential for capsule expression in V. vulnificus.     

Escherichia coli genes expressed preferentially in an aquatic environment

We isolated genomic clones that contain the 5'-flanking region of the mouse activin beta A subunit gene. The nucleotide sequence determination of the 5'-flanking region of the gene and the comparison of that with the reported mouse cDNA structure identified the putative 5' regulatory region, a novel first exon and a part of the first intron of the gene within this region. The putative 5' regulatory region of the mouse activin beta A subunit gene directed the expression of CAT gene in transfected HT1080 cells. Successive deletions of this region demonstrated a 400-bp region that exerts a strong positive effect on promoter activity of the mouse activin beta A subunit gene.     

Overwhelming sepsis with Vibrio vulnificus: a coastal pathogen in Oklahoma

Vibrio vulnificus has been associated with three main clinical syndromes; primary septicemia; wound infection, and gastroenteritis. This organism has increased virulence for persons with underlying medical conditions that predispose to iron overload or an impaired immune system. Since the organism proliferates more readily in warm, coastal waters, such infections are more commonly found in those regions. Infection can result from the ingestion of contaminated, undercooked seafood; contact of a wound with seawater; or a puncture wound sustained from a contaminated surface. Vibrio infections rarely occur in inland areas, but when they do occur, they are usually a result of the contact of wounds with contaminated, brackish water or the ingestion of raw shellfish. Because infections with this organism occur less frequently in non-coastal regions, the diagnosis may not be suspected initially in susceptible individuals and a delay of treatment may result. We present a case of V. vulnificus sepsis occurring in a man with underlying liver disease and a history of row oyster consumption in Oklahoma and discuss the clinical manifestations of primary sepsis with this organism as well as prevention strategies.     

Prevention of Vibrio vulnificus infections. Assessment of regulatory educational strategies

CONTEXT: Vibrio vulnificus-related disease caused by eating contaminated raw oysters prompted California to implement regulatory educational initiatives in 1991. OBJECTIVE: To assess California guidelines and education efforts with regard to the prevention of V. vulnificus infections in Los Angeles County and to evaluate compliance with state regulations mandating posting of warning signs concerning risks of eating raw oysters. DESIGN: Review of epidemiologic investigations of V. vulnificus infections in Los Angeles County between 1993 and 1995; telephone interviews of patients or surrogates; and a survey of restaurants serving raw oysters in Los Angeles County. SETTING: General community. MAIN OUTCOME MEASURES: Prior warning of patients and posting of warning signs in restaurants. RESULTS: Recent cases of V. vulnificus infections in Los Angeles County suggest that a unique, vulnerable group (uninsured Hispanic men with viral or alcoholic liver disease) has not been reached through education efforts. Of a total of 11 cases, information regarding being warned about the hazard of eating raw shellfish was available for 8; of these, only 1 case was reported as having been warned, but he had misunderstood the preventive message. Warning signs were not posted adequately in more than 50% of restaurants surveyed and one third of these establishments had signs in English only. Warnings were never located on dining tables and rarely included in menus. CONCLUSION: A more effective strategy is required to prevent V.vulnificus infections in Los Angeles County.     

Structure determination of the capsular polysaccharide from Vibrio vulnificus strain 6353

Although significant progress has been made towards the understanding of cellular and molecular mechanisms underlying the pathogenetic pathways of transplant arteriosclerosis, its knowledge is still not comprehensive. Nevertheless, experimental and clinical studies have enabled us to discover some of the complex processes involved in the progression and evolution of transplant arteriosclerosis. Despite the advances in transplantation immunology and atherosclerosis research, transplant arteriosclerosis still remains a major cause of allograft failure. A curative treatment, in order to inhibit or at least modify the development of transplant arteriosclerosis, is urgently needed. This review article highlights some of the more recent aspects of cellular and molecular pathology of transplant arteriosclerosis that may add to our current and future diagnostic and curative interventions.     

Comparison of ribotyping and randomly amplified polymorphic DNA PCR for characterization of Vibrio vulnificus

A total of 85 isolates of Vibrio vulnificus were characterized by ribotyping with a probe complementary to 16S and 23S rRNA of Escherichia coli and by randomly amplified polymorphic DNA-PCR (RAPD-PCR) with a 10-mer oligonucleotide primer. The RAPD-PCR results were scanned, and the images were analyzed with a computer program. Ribotype membranes were evaluated visually. Both the ribotyping and the RAPD-PCR results showed that the collection of strains was genetically very heterogeneous. Ribotyping enabled us to differentiate U.S. and Danish strains and V. vulnificus biotypes 1 and 2, while the RAPD-PCR technique was not able to correlate isolates with sources or to differentiate the two biotypes, suggesting that ribotyping is useful for typing V. vulnificus strains whereas RAPD-PCR profiles may subdivide ribotypes. Two Danish clinical biotype 2 strains isolated from fishermen who contracted the infection cleaning eels belonged to the same ribotype as three eel strains (biotype 2), providing further evidence that V. vulnificus biotype 2 is an opportunistic pathogen for humans. One isolate (biotype 2) from Danish coastal waters also showed the same ribotype as the eel strains. This is, to our knowledge, the first time the isolation of V. vulnificus biotype 2 from coastal waters has been described.     

Survival of Vibrio vulnificus in whole blood from patients with chronic liver diseases: association with phagocytosis by neutrophils and serum ferritin levels

Vibrio vulnificus causes severe wound infections and sepsis, mostly in persons with chronic liver diseases. Survival of this organism in the whole blood collected from healthy volunteers and patients with chronic hepatitis, liver cirrhosis, and hepatoma was analyzed as an indication of susceptibility. The bacterial numbers in the blood after 5 h of incubation tended to increase with the severity of the liver disease and differed significantly between hepatoma patients and healthy volunteers (P<.05). Survival of V. vulnificus in the whole blood correlated positively with serum ferritin concentration (r=.266; P<.05) and percentage of transferrin iron saturation (r=. 200; P<.05) and correlated negatively with serum C4 concentration (r=-.198; P<.05) and phagocytosis by neutrophils (r=-.204; P<.05). Among these parameters, low phagocytosis activity (P<.01) and high ferritin level (P<.01) in the blood were the independent predictors.     

Infection by Vibrio vulnificus after a prick from from the spine of a Tilapia

Vibrio vulnificus is a Gram-negative bacterium living in warm salty water that produces a spectrum of human disease which may progress to devastating, sometimes fatal infections in susceptible individuals. Such infections have rarely been reported in Israel. However, over the past few months we have been seeing a sharp increase in V. vulnificus infections with a common history of injury to extremities by the sharp spines of Tilapia zillii, ("amnon" or St. Peter's fish). Clinical suspicion and prompt intervention prevent the untoward consequences of misdiagnosis or delay.     

Angiogenesis in rheumatoid arthritis: pathogenic and clinical significance

In summary, angiogenesis, the formation of new blood vessels, is important in leukocyte extravasation and thus the pathogenesis of RA. The outcome of neovascularization highly depends on the imbalance between angiogenic and angiostatic mediators produced in the rheumatoid synovium. Therefore, angiogenesis research is important for the understanding of the pathogenesis of inflammatory arthritis. In addition, existing and potential angiostatic drugs may be useful for future therapy of RA.     

Comparative study of biological properties and electrophoretic characteristics of lipopolysaccharide from eel-virulent and eel-A virulent Vibrio vulnificus strains

In Vibrio vulnificus, virulence for eels is associated with serovar E strains. In this study, we investigated some biological properties of purified lipopolysaccharides (LPSs) from serovar E and non-serovar E strains. Purified LPSs retained their O-polysaccharidic side chains and did not show any differences that could be related to host specificity, except for serological differences.     

Influence of water temperature and salinity on Vibrio vulnificus in Northern Gulf and Atlantic Coast oysters (Crassostrea virginica)

This study investigated the temperature and salinity parameters associated with waters and oysters linked to food-borne Vibrio vulnificus infections. V. vulnificus was enumerated in oysters collected at three northern Gulf Coast sites and two Atlantic Coast sites from July 1994 through September 1995. Two of these sites, Black Bay, La., and Apalachicola Bay, Fla., are the source of the majority of the oysters implicated in V. vulnificus cases. Oysters in all Gulf Coast sites exhibited a similar seasonal distribution of V. vulnificus: a consistently large number (median concentration, 2,300 organisms [most probable number] per g of oyster meat) from May through October followed by a gradual reduction during November and December to < or = 10 per g, where it remained from January through mid-March, and a sharp increase in late March and April to summer levels. V. vulnificus was undetectable (< 3 per g) in oysters from the North and South Carolina sites for most of the year. An exception occurred when a late-summer flood caused a drop in salinity in the North Carolina estuary, apparently causing V. vulnificus numbers to increase briefly to Gulf Coast levels. At Gulf Coast sites, V. vulnificus numbers increased with water temperatures up to 26 degrees C and were constant at higher temperatures. High V. vulnificus levels (> 10(3) per g) were typically found in oysters from intermediate salinities (5 to 25 ppt). Smaller V. vulnificus numbers (< 10(2) per g) were found at salinities above 28 ppt, typical of Atlantic Coast sites. On 11 occasions oysters were sampled at times and locations near the source of oysters implicated in 13 V. vulnificus cases; the V. vulnificus levels and environmental parameters associated with these samples were consistent with those of other study samples collected from the Gulf Coast from April through November. These findings suggest that the hazard of V. vulnificus infection is not limited to brief periods of unusual abundance of V. vulnificus in Gulf Coast oysters or to environmental conditions that are unusual to Gulf Coast estuaries.     

Comparison of a commercial biochemical kit and an oligonucleotide probe for identification of environmental isolates of Vibrio vulnificus

Methods for the identification and isolation of environmental isolates of Vibrio vulnificus were evaluated. Alkaline peptone water supplemented with polymyxin B and colistin-polymyxin B-cellobiose agar were employed for the isolation of suspected V. vulnificus from water, sediment and shellfish samples. When comparing the identification of putative V. vulnificus obtained with the API 20E assay and an oligonucleotide probe, 29 API 20E profiles were obtained with only four profiles (representing 20 isolates) reaching the identification threshold of V. vulnificus among a total of 66 isolates hybridizing with the probe. The results indicated that, compared with colony hybridization, the API 20E assay was not adequate for the identification of environmental isolates of V. vulnificus.     

Purification and characterization of a cysteine protease produced by pathogenic luminous Vibrio harveyi

A histologic and biochemical comparison of interface membranes around femoral components of bipolar endoprostheses (n = 17) and total hip prostheses (n = 17) inserted without cement was conducted. The patients' profiles were similar in both groups with respect to age, sex, primary diagnosis, weight, and the interval between primary and revision arthroplasty. Macroscopically, marked circumferential abrasion of the polyethylene insert in the retrieved bipolar cups was noted. Histologic analysis revealed significantly larger amounts of polyethylene debris in the bipolar group. The membranes from the bipolar group also produced significantly greater amounts of prostaglandin E2 (P < .05). The inflammatory membranes associated with large amounts of polyethylene debris may have contributed to aseptic loosening and osteolysis in patients with a bipolar hip prosthesis.     

Hsp70 and Hsc70 are preferentially expressed in differentiated epithelial cells in normal human endometrium and ectocervix

This paper addresses parametric system identification of linear and nonlinear dynamic systems by analysis of the input and output signals. Specifically, we investigate the relationship between estimation of the system using a feedforward neural network model and estimation of the system by use of linear and nonlinear autoregressive moving-average (ARMA) models. By utilizing a neural network model incorporating a polynomial activation function, we show the equivalence of the artificial neural network to the linear and nonlinear ARMA models. We compare the parameterization of the estimated system using the neural network and ARMA approaches by utilizing data generated by means of computer simulations. Specifically, we show that the parameters of a simulated ARMA system can be obtained from the neural network analysis of the simulated data or by conventional least squares ARMA analysis. The feasibility of applying neural networks with polynomial activation functions to the analysis of experimental data is explored by application to measurements of heart rate (HR) and instantaneous lung volume (ILV) fluctuations.     

The screening detection of the antigens of pathogenic enterobacteria in the biological fluids of patients with chronic intestinal diseases

Screening detection of the antigens of some pathogenic enterobacteria in the coagglutination test with the use of Shigella (S. sonnei, S. flexneri 2a, 1b, 6), Salmonella (groups A, B, C, D, E) and Yersinia (Y. pseudotuberculosis, serovars I and III, Y. enterocolitica 03 and 09) diagnostica in patients with chronic enteric diseases, hospitalized in a noninfectious ward, has demonstrated a high incidence of the above antigens. S. flexneri antigens have shown the highest detection rate. The results thus obtained indicate that these infective agents probably take part in the development of exacerbations of chronic enteric diseases and, therefore, a comprehensive examination of this group of patients is necessary with a view to the detection of bacterial enteric infection.