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C Martin

Publications and source records attributed to C Martin.

At least 163 records · Page 9Linked to original sources
PubMed2001

Different mechanisms mediate the rejection of porcine neurons and endothelial cells transplanted into the rat brain.

In order to investigate the early cellular responses mediating xenograft rejection in the brain, porcine aortic endothelial cells (PAEC) or porcine fetal mesencephalic neurons (PNEU) were transplanted into the striatum of LEW.1A rats. PAEC were detected with a specific anti-beta1 integrin antibody, and PNEU with an anti-porcine neurofilament antibody, or an antibody recognizing the NeuN antigen. PAEC grafts were massively infiltrated within 24 h by OX42-positive cells, which may correspond to polymorphonuclear (PMN) cells or macrophages. At that moment, the graft contained numerous cells expressing the inducible isoform of NO-synthase (iNOS). Infiltration by ED1-positive macrophages was effective after three days. The beta1-integrin labeling decreased from that time-point to day 7 post-implantation, and vanished after 11 days. Although some OX8-positive cells were present around the graft as soon as 3 days after transplantation, cells expressing the T-cell receptor (TCR)-beta chain infiltrated the graft after 7 days and their number remained low. A strong, diffuse OX8-and ED1-positive immunoreactive material remained in the scar up to the third week. In striking contrast, PNEU grafts remained poorly infiltrated by OX42- or ED1-positive cells during the first two weeks. A massive infiltration by macrophages and TCRbeta-positive lymphocytes occurred after 3 weeks. Natural killer (NK) cells were more scarce. The inflammation territory enlarged, and blood vessels were overloaded with macrophages or lymphocytes. Nevertheless, the graft contained NeuN-positive nuclei and neurites harbouring the porcine neurofilament protein. Hence, rejection was not completed at this time-point. These results suggest that the rapid rejection of PAEC is mainly driven by macrophages and possibly PMN cells, unlike PNEU, whose rejection is delayed and also involves lymphocytes. Differences in immunogenicity of grafted cells and/or patterns of production of pro-inflammatory cytokines may account for these contrasted rejection kinetics.

Animals↗
PubMed2001

Detailed characterization of cysteine-less P-glycoprotein reveals subtle pharmacological differences in function from wild-type protein.

1. Subtle alterations in the coupling of drug binding to nucleotide hydrolysis were observed following mutation of all seven endogenous cysteine residues to serines in the human multidrug resistance transporter, P-glycoprotein. Wild-type (wt) and the mutant (cys-less) forms of P-gp were expressed in Trichoplusia ni (High Five) cells and purified by metal affinity chromatography in order to undertake functional studies. 2. No significant differences were observed in substrate ([(3)H]-azidopine) binding to wt or cys-less P-gp. Furthermore, neither the transported substrate vinblastine, nor the modulator nicardipine, differed in their respective potencies to displace [(3)H]-azidopine from the wt or cys-less P-gp. These results suggest that respective binding sites for these drugs were unaffected by the introduced cysteine to serine substitutions. 3. The Michaelis-Menten characteristics of basal ATP hydrolysis of the two isoforms of P-gp were identical. The maximal ATPase activity in the presence of vinblastine was marginally reduced whilst the K(m) was unchanged in cys-less P-gp compared to control. However, cys-less P-gp displayed lower overall maximal ATPase activity (62%), a decreased K(m) and a lower degree of stimulation (76%) in the presence of the modulator nicardipine. 4. Therefore, the serine to cysteine mutations in P-gp may suggest that vinblastine and nicardipine transduce their effects on ATP hydrolysis through distinct conformational pathways. The wt and cys-less P-gp isoforms display similarity in their fundamental kinetic properties thereby validating the use of cys-less P-gp as a template for future cysteine-directed structure/function analysis.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

The relationship between emotions and stress among mental health nurses.

This paper presents findings from an exploratory correlational study that examined the relationships between Emotional Competency, Trait Affectivity, Stress and Experienced Emotions among 43 mental health nurses in Australian regional hospitals. A significant relationship was found between Emotional Competency and Personal Self-doubt in male nurses only; however, no association was found between Emotional Competency and Experienced Emotions. Trait Affectivity was found to be associated with Experienced Emotions but not Stress. Gender differences were found in Trait Affectivity and Experienced Emotions. The results of the study have implications for the retention of mental health nurses in their profession.

Adaptation, Psychological↗
PubMed2001

Effect of prophylactic transfusion of stored RBCs on oxygen reserve in response to acute isovolemic hemorrhage in a rodent model.

BACKGROUND: The storage of RBCs results in a time-related decline in 2,3 DPG that may reduce the ability to unload oxygen (O(2)) to tissue. The objective of this study was to compare the effect that transfusion of stored 2,3 DPG-depleted rat blood (7 days in CPDA-1) had on the O(2) reserve in conscious rats, with that of the transfusion of fresh blood (<2-hour storage). STUDY DESIGN AND METHODS: Anemic rats (Hb, 80 g/L) received either fresh packed RBCs or stored RBCs to raise Hb levels to 140 g per L. They then underwent isovolemic hemorrhage mimicking surgical blood loss to the point of O(2) supply dependency (OSD). Critical O(2) delivery (DO(2)crit), Hb concentration, and O(2) extraction at OSD were measured in a metabolic chamber. RESULTS: After transfusion, RBC DPG decreased by 50 percent in the stored-blood group, and the p50 value decreased by 5 mmHg (32.1 +/- 2.5 mmHg vs. 37.5 +/- 3.0). DO(2)crit was similar in the two groups (fresh blood: 2.79 +/- 0.44 mL/min x g(-1); stored blood, 2.99 +/- 0.76 mL/min x g(-1)). The critical Hb concentration at DO(2)crit was higher in the stored-blood group (44 +/- 4 g/L) than in the fresh-blood group (38 +/- 5 g/L); the cardiac index and O(2) extraction ratio in the two groups were not different. Under conditions of severe normovolemic anemia in rats, depletion of DPG and a decrease in p50 had only minor effects on the O(2) reserve. At OSD, under these conditions, O(2) consumption is not limited by diffusion. CONCLUSION: The physiologic impact of DPG depletion in transfused stored blood on oxygen availability in normal rats appears to be small and may be clinically inconsequential.

Anemia↗
PubMed2001

[Difficulties in the transfer of drug therapy from inpatient to ambulatory treatment].

The prospective study compares prescribed drugs of 192 primarily cardiological patients at discharge and 7 weeks later in ambulatory care. The data were determined by discharge summaries and by standardized patient-questionnaires. The drug division was made with the ATC-classification according to the recommendations of the World Health Organisation for Drug Utilisation Studies. The intraindividual cost comparison was calculated by current pharmacy sale prices. The findings were changes in hospital discharge medications in ambulatory care in over 2/3 of the cases. The most frequent change was the additional prescribing of drug groups. The average daily tablet number increased in patients with the same or worsened subjective feeling after discharge. Additionally we found in a number of patients a change of drug therapy within the ATC-groups, or in fact, withdrawal of drug therapy all together. The frequency of changes increased with the number of patient/doctor contacts. The observation that the average daily therapeutical cost decreased just slightly could give an indication that cost saving was a minor part of the doctors decision for drug changing. However, the frequency of changes has shown to be dependent upon the specialities of the physician or pharmaceutical group.

Adult↗
PubMed2001

Diagnosis of culture-negative endocarditis: the role of the Duke criteria and the impact of transesophageal echocardiography.

BACKGROUND: The Duke criteria have been shown to be more sensitive than the von Reyn criteria in the diagnosis of culture-positive endocarditis but to date have not been fully validated for culture-negative endocarditis (CNE). The aim of this study was (1) to compare the diagnostic accuracy of the Duke criteria versus clinical judgment and the von Reyn criteria in CNE and (2) to assess the diagnostic impact of transesophageal echocardiography (TEE) on the Duke criteria in CNE. METHODS: The study group consisted of 49 patients with suspected CNE in whom the presence (n = 32) or absence (n = 17) of endocarditis was confirmed by surgery, autopsy, or both. All patients underwent transthoracic echocardiography (TTE) and TEE. They were classified into a Duke category initially with TTE data only, and then the Duke categories were reevaluated with the additional TEE data. RESULTS: The Duke criteria demonstrated a significantly higher sensitivity (72%) than the von Reyn criteria (28%; P =.0008) and a higher specificity (100%) than clinical judgment (76%; P =.02). No major differences were noted between sensitivities of the Duke criteria and clinical judgement. TEE significantly augmented the capacity to diagnose CNE by Duke criteria versus TTE (P <.05). CONCLUSIONS: The Duke criteria are of high diagnostic validity for the conduction of clinical studies on CNE. They have the potential to affect clinical decision-making, based on the higher specificity versus clinical judgment. TEE appears to be crucial for the diagnosis of CNE when the Duke criteria are applied. The diagnostic differentiation between CNE, sclerotic valve degeneration, and nonbacterial thrombotic endocarditis remains a challenge.

Adult↗
PubMed2001

Comparison of non-tracer and tracer methods for determination of volatile fatty acid production rate in the rumen of sheep fed on two levels of intake.

The aim of the present work was to estimate volatile fatty acid (VFA) production rate in the rumen of sheep fed two levels of intake using both a tracer (TM; by isotope dilution) and a non-tracer method (NTM; by supplementary infusion) in steady-state conditions. Six wethers received a diet containing 700 g lucerne hay and 300 g ground maize/kg in eight equal meals at 3 h intervals per d. The diet (9.8 MJ metabolizable energy (ME)/kg DM) was offered at 90 % ad libitum consumption (high intake, HI) or 45 % ad libitum consumption (low intake, LI) in a crossover design. Each sheep received five intrarumen VFA solutions infused continuously for 24 h at rates of 250 ml and 165 ml/h for the HI and LI respectively. The first infusion, considered as a control treatment (Con), consisted of a solution of [1-(13)C]propionate (7 mmol/d). The four other solutions were isoenergetic (1.9 MJ ME/kg DM intake) mixtures of unlabelled propionate (C(3)) and butyrate (C(4)) at different levels: 0.90 mol C(4)/kg DM intake; 0.60 mol C(3)/kg DM intake; 0.30 mol C(3)/kg DM intake; 1.35 mol C(3)/kg DM intake. The VFA infusions did not affect rumen fermentation of the basal diet (pH, osmotic pressure, protozoa numbers), and comparable DM digestibility of the diet among the different treatments was observed. Both estimation methods demonstrated a similar increase (1.7-fold) in the rumen VFA production rate of sheep fed at intakes varying between 0.9 to 1.7 times maintenance. Irrespective of the intake level, the rumen production rate of individual VFA was on average 1.5-fold higher when estimated by the TM compared with the NTM. Rumen VFA production rates estimated by the NTM and TM represented 80 % and 120 % ME intake respectively. The difference between NTM and TM estimates seems likely to be caused mainly by overestimation of the VFA production rates by the TM.

Analysis of Variance↗
PubMed2001

Polymerase chain reaction for diagnosis of cerebral toxoplasmosis in cerebrospinal fluid in HIV-positive patients.

It is important but sometimes difficult to establish a diagnosis of toxoplasma encephalitis (TE) in an HIV-positive immunodeficient patient. The most promising non-invasive method is polymerase chain reaction (PCR) for Toxoplasma gondii in cerebrospinal fluid (CSF). In a retrospective study PCR was used to analyse CSF for the presence of T. gondii DNA in 5 HIV-infected patients with a clinical suspicion of TE (group 1), 8 patients with other HIV-associated symptoms (group 2) and 7 other patients with neurological disorders (group 3). PCR was positive in 2/4 patients with a final diagnosis of TE and negative in all remaining patients in all 3 groups. The 2 patients with positive PCR had a fulminant course and experienced treatment failure. The albumin index was elevated in 4/5 patients in group 1, of whom 3/4 had a final diagnosis of TE, with suspected TE in 1. This small study confirms earlier data indicating that the PCR test has a low sensitivity but a high specificity.

AIDS-Related Opportunistic Infections↗
PubMed2001

Subjective experience after traumatic brain injury.

The present investigation aims to show which specific difficulties are reported with greater frequency in traumatic brain injury (TBI) patients than in controls, and in hetero-assessment than in self-assessment. Ninety-seven patients with severe TBI were compared to 97 controls matched for age and gender. The 63-item European Brain Injury Questionnaire (EBIQ) was completed by patients, close relatives and controls. A principal component analysis showed three main factors: "depressive mood", "cognitive difficulties", and "difficulties in social interactions". Relatives scored higher than patients for items concerning the three domains. Patients scored higher than controls for "depressive mood" and "cognitive difficulties", but not for "difficulties in social interactions", which included items related to both self-assertion and lack of self-control. After TBI, emotional problems and, especially, depressive mood associated to cognitive difficulties have an important impact in everyday life and family functioning. Difficulties in social interactions are not specific of TBI patients.

Adolescent↗
PubMed2001

A psychological assessment of adolescent and young adult inpatients after traumatic brain injury.

The purpose of this study was to evaluate the cognitive, behavioural, depressive and self-awareness disorders, and their relationships, after severe traumatic brain injury (TBI) in adolescent and young adult inpatients. Two groups of patients with (n = 83) and without (n = 103) TBI, aged 14-25 years, hospitalized after severe traumatic pathology, were compared using the clinician's report and self-report. A higher frequency of depressive tendencies in TBI patients than in controls was shown in the clinician's therapeutic attitude (i.e. prescription of antidepressant drugs), the clinician's report and the self-report. The same difference between the two groups was observed for behavioural and schooling problems in the clinician's report, but not in the self-report. Discrepancies between self- and clinician's evaluation were in favour of a lack of self-awareness of behavioural and cognitive disorders among TBI patients. Correlations of depressive mood with anxiety and cognitive complaints were stronger in TBI than in non-TBI patients. Depression in TBI patients seems compatible with some degree of lack of self-awareness of cognitive and behavioural difficulties.

Adolescent↗
PubMed2001

Preliminary study of the deposition of aerosol in the maxillary sinuses using a plastinated model.

In spite of the widespread use of aerosols in respiratory diseases, very few studies have been performed in the field of ear, nose, and throat (ENT) disorders. The conditions for penetration of aerosols inside the sinus cavities are thus still not understood fully. The aim of this study was to investigate the penetration of aerosols inside maxillary sinuses in vitro, using plastinated models. Three plastinated specimens of the nose and sinuses were made from three different corpses. These specimens were validated by CT scans and were used to study deposition of aerosol in the maxillary sinuses. We performed scintigraphic images of the models in above, face, and profile views using a technetium (99mTc)-labelled solution to show aerosol deposition. We also counted the radioactivity deposited on gauze compresses placed inside the maxillary sinuses. In addition, we constructed a measuring unit with miniature humidity sensors placed inside the sinuses. We recorded the changes in relative humidity observed during nebulization. Results from these studies showed that scintigraphic images of the specimen, whatever the incidence of the views, were not accurate enough to differentiate the aerosol deposition in the maxillary sinuses from that in the nasal cavity. Using indirect counting on gauze compresses made possible the quantification of local aerosol deposition, and we found that aerosols entered into the sinuses. This confirmed that aerosols could reach the middle meatus, which is the main area for sinusitis disorders. The increased activity compared to background varied from 17 to 127%. The humidity sensors recorded changes in relative humidity during the nebulization. These humidity changes fitted a nonlinear model represented by the equation: y = b0 (1 - e(-b1t)), where b0 is the plateau and b1 is the speed to reach the plateau. These techniques may be useful in the future for in vitro characterization of aerosol penetration into the maxillary sinuses.

Aerosols↗
PubMed2001

Is a low transfusion threshold safe in critically ill patients with cardiovascular diseases?

OBJECTIVE: To compare a restrictive red blood cell transfusion strategy with a more liberal strategy in volume-resuscitated critically ill patients with cardiovascular disease. SETTING: Twenty-two academic and three community critical care units across Canada. STUDY DESIGN: Randomized controlled clinical trial. STUDY POPULATION: Three hundred fifty-seven critically ill patients with cardiovascular diseases from the Transfusion Requirements in Critical Care trial who had a hemoglobin concentration of <90 g/L within 72 hrs of admission to the intensive care unit. INTERVENTIONS: Patients were randomized to a restrictive strategy to receive allogeneic red blood cell transfusions at a hemoglobin concentration of 70 g/L (and maintained between 70 and 90 g/L) or a liberal strategy to receive red blood cells at 100 g/L (and maintained between 100 and 120 g/L). RESULTS: Baseline characteristics in the restrictive (n = 160) and the liberal group (n = 197) were comparable, except for the use of cardiac and anesthetic drugs (p <.02). Average hemoglobin concentrations (85 +/- 6.2 vs. 103 +/- 6.7 g/L; p <.01) and red blood cell units transfused (2.4 +/- 4.1 vs. 5.2 +/- 5.0 red blood cell units; p <.01) were significantly lower in the restrictive compared with the liberal group. Overall, all mortality rates were similar in both study groups, including 30-day (23% vs. 23%; p = 1.00), 60-day, hospital, and intensive care unit rates. Changes in multiple organ dysfunction from baseline scores were significantly less in the restrictive transfusion group overall (0.2 +/- 4.2 vs. 1.3 +/- 4.4; p =.02). In the 257 patients with severe ischemic heart disease, there were no statistically significant differences in all survival measures, but this is the only subgroup where the restrictive group had lower but nonsignificant absolute survival rates compared with the patients in the liberal group. CONCLUSION: A restrictive red blood cell transfusion strategy generally appears to be safe in most critically ill patients with cardiovascular disease, with the possible exception of patients with acute myocardial infarcts and unstable angina.

APACHE↗
PubMed2001

Macrophage migration inhibitory factor and innate immune responses to bacterial infections.

OBJECTIVES: To review the role of macrophage migration inhibitory factor (MIF) in host responses to infection and to explore the potential of MIF as a novel target for therapeutic intervention in patients with severe sepsis and septic shock. DATA SOURCES: Published articles on the role of MIF in innate immune responses against microbial pathogens. DATA SUMMARY: MIF has emerged recently as an important effector molecule of the innate immune system. MIF is expressed constitutively by monocytes/macrophages, T cells, B cells, endocrine cells, and epithelial cells. Microbial toxins and cytokines are powerful inducers of MIF release by immune cells. MIF expression is up-regulated during the course of inflammatory and infectious diseases and was found to play an important role in the pathogenesis of sepsis and septic shock. CONCLUSION: Given the role of MIF in innate immune responses against microbial pathogens and in the regulation of inflammatory responses, modulation of MIF production or neutralization of its activity may offer new therapeutic options for the management of patients with sepsis.

Animals↗
PubMed2001

Comprehensive genome sequence analysis of a breast cancer amplicon.

Gene amplification occurs in most solid tumors and is associated with poor prognosis. Amplification of 20q13.2 is common to several tumor types including breast cancer. The 1 Mb of sequence spanning the 20q13.2 breast cancer amplicon is one of the most exhaustively studied segments of the human genome. These studies have included amplicon mapping by comparative genomic hybridization (CGH), fluorescent in-situ hybridization (FISH), array-CGH, quantitative microsatellite analysis (QUMA), and functional genomic studies. Together these studies revealed a complex amplicon structure suggesting the presence of at least two driver genes in some tumors. One of these, ZNF217, is capable of immortalizing human mammary epithelial cells (HMEC) when overexpressed. In addition, we now report the sequencing of this region in human and mouse, and on quantitative expression studies in tumors. Amplicon localization now is straightforward and the availability of human and mouse genomic sequence facilitates their functional analysis. However, comprehensive annotation of megabase-scale regions requires integration of vast amounts of information. We present a system for integrative analysis and demonstrate its utility on 1.2 Mb of sequence spanning the 20q13.2 breast cancer amplicon and 865 kb of syntenic murine sequence. We integrate tumor genome copy number measurements with exhaustive genome landscape mapping, showing that amplicon boundaries are associated with maxima in repetitive element density and a region of evolutionary instability. This integration of comprehensive sequence annotation, quantitative expression analysis, and tumor amplicon boundaries provide evidence for an additional driver gene prefoldin 4 (PFDN4), coregulated genes, conserved noncoding regions, and associate repetitive elements with regions of genomic instability at this locus.

Animals↗
PubMed2001

Heterogeneity of Shiga toxin-producing Escherichia coli strains isolated from hemolytic-uremic syndrome patients, cattle, and food samples in central France.

A detailed analysis of the molecular epidemiology of non-O157:H7 Shiga toxin-producing Escherichia coli (STEC) was performed by using isolates from sporadic cases of hemolytic-uremic syndrome (HUS), animal reservoirs, and food products. The isolates belonged to the O91 and OX3 serogroups and were collected in the same geographical area over a short period of time. Five typing methods were used; some of these were used to explore potentially mobile elements like the stx genes or the plasmids (stx(2)-restriction fragment length polymorphism [RFLP], stx(2) gene variant, and plasmid analyses), and others were used to study the whole genome (ribotyping and pulsed-field gel electrophoresis [PFGE]). The techniques revealed that there was great diversity among the O91 and OX3 STEC strains isolated in central France. A close relationship between strains of the same serotype having the same virulence factor pattern was first suggested by ribotyping. However, stx(2)-RFLP and stx(2) variant analyses differentiated all but 5 of 21 isolates, and plasmid analysis revealed further heterogeneity; a unique combination of characteristics was obtained for all strains except two O91:H21 isolates from beef. The latter strains were shown by PFGE to be the most closely related isolates, with >96% homology, and hence may be subtypes of the same strain. Overall, our results indicate that the combination of stx(2)-RFLP, stx(2) variant, and plasmid profile analyses is as powerful as PFGE for molecular investigation of STEC diversity. Finally, the non-O157:H7 STEC strains isolated from HUS patients were related to but not identical to those isolated from cattle and food samples in the same geographical area. The possibility that there are distinct lineages of non-O157:H7 STEC, some of which are more virulent for humans, should be investigated further.

Animals↗
PubMed2001

B-cell deficiency suppresses vaccine-induced protection against murine filariasis but does not increase the recovery rate for primary infection.

To establish the role of B cells and antibodies in destroying filariae, mice lacking mature B cells and therefore unable to produce antibodies were used. Litomosoides sigmodontis offers a good opportunity for this study because it is the only filarial species that completes its life cycle in mice. Its development was compared in B-cell-deficient mice (BALB/c muMT mice) and wild-type BALB/c mice in two different in vivo situations, vaccination with irradiated larvae and primary infection. In all cases, mice were challenged with subcutaneous inoculation of 40 infective larvae. Vaccine-induced protection was suppressed in B-cell-deficient mice. In these mice, eosinophils infiltrated the subcutaneous tissue normally during immunization; however, their morphological state did not change following challenge inoculation, whereas in wild-type mice the percentage of degranulated eosinophils was markedly increased. From this, it may be deduced that the eosinophil-antibody-B-cell complex is the effector mechanism of protection in vaccinated mice and that its action is fast and takes place in the subcutaneous tissue. In primary infection, the filarial survival and growth was not modified by the absence of B cells. However, no female worm had uterine microfilariae, nor did any mice develop a patent infection. In these mice, concentrations of type 1 (gamma interferon) and type 2 (interleukin-4 [IL-4], IL-5 and IL-10) cytokines in serum were lower and pleural neutrophils were more numerous. The effects of the muMT mutation therefore differ from those in B1-cell-deficient mice described on the same BALB/c background, which reveal a higher filarial recovery rate and microfilaremia. This outlines B2-cell-dependent mechanisms as favorable to the late maturation of L. sigmodontis.

Animals↗
PubMed2001

Stx2 subtyping of Shiga toxin-producing Escherichia coli isolated from cattle in France: detection of a new Stx2 subtype and correlation with additional virulence factors.

At least 11 Stx2 variants produced by Shiga toxin-producing Escherichia coli (STEC) isolated from patients and animals have been described. The Stx2 subtyping of STEC isolated from healthy cows positive for stx(2) (n = 104) or stx(2) and stx(1) (n = 63) was investigated. Stx2vh-b, Stx2 (renamed Stx2-EDL933), and Stx2vh-a were the subtypes mostly detected among the bovine isolates (39.5, 39, and 25.5%, respectively). Stx2e was not present, and subtypes included in the Stx2d group (Stx2d-OX3a, Stx2d-O111, and Stx2d-Ount) were found infrequently among the isolates examined (8.5%). A combination of two distinct Stx2 subtypes was observed among 23.5% of the strains. For the first time, a combination of three subtypes (Stx2-EDL933/Stx2vh-b/Stx2d and Stx2vh-a/Stx2vh-b/Stx2d) was detected (3.5% of the isolates). In addition, bovine STEC harboring stx(1) and one or two stx(2) genes appeared highly cytotoxic toward Vero cells. A new Stx2 subtype (Stx2-NV206), present among 14.5% of the isolates, showed high cytotoxicity for Vero cells. Two amino acid residues (Ser-291 and Glu-297) important for the activation of Stx2 by human intestinal mucus were conserved on the Stx2-NV206 A subunit. The gene encoding Ehx enterohemolysin was prominent among STEC harboring stx(2)-EDL933 alone (78%) or a combination of stx(2)-EDL933 and stx(2)vh-b (85%). In addition, Stx2-EDL933 and/or Stx2vh-b subtypes were highly associated with other putative virulence factors such as Stx1 and EspP extracellular serine protease, but not with EAST1 enterotoxin.

Animals↗