Biomedical subjects

Miguel Blanco

Publications and source records attributed to Miguel Blanco.

At least 19 recordsLinked to original sources

PubMed2006

Phage types, virulence genes and PFGE profiles of Shiga toxin-producing Escherichia coli O157:H7 isolated from raw beef, soft cheese and vegetables in Lima (Peru).

The present study was conducted in Lima Metropolitana to evaluate the prevalence of Shiga toxin-producing Escherichia coli (STEC) O157:H7 in raw beef, raw ground beef, soft cheese and fresh vegetables, sampled at different markets in the city. Between October 2000 and February 2001, 407 food samples were collected from different markets in the 42 districts of Lima Metropolitana. Samples were assayed for E. coli O157 by selective enrichment in modified Tryptic Soy Broth containing novobiocin, followed by immunomagnetic separation (IMS) and plating onto sorbitol MacConkey agar supplemented with cefixime and potassium tellurite. Fifty (12.3%) of 407 food samples resulted positive for E. coli O157 isolation (23 of 102 ground beef; 15 of 102 beef meat; eight of 102 soft cheese and four of 101 fresh vegetables). Thirty-five E. coli O157 isolates were further analysed for the presence of virulence genes. All 35 were positive by PCR for O157 rfbE, fliCh7, eae-gamma1 and ehxA genes. In addition, genes encoding Shiga toxins were detected in 33 of 35 isolates, five isolates (14%) encoded stx(1), stx(2), and 28 (80%) stx2 only. The isolates were of seven different phage types (PT4, PT8, PT14, PT21, PT34, PT54, and PT87) with three phage types accounting for 80% of isolates: PT4 (15 isolates), PT14 (8 isolates), and PT21 (5 isolates). Interestingly, the majority (31 of 35; 89%) of E. coli O157:H7 isolates characterized in this study belonged mainly to the phage types previously found in STEC O157:H7 strains associated with severe human disease in Europe and Canada. Pulsed-field gel electrophoresis (PFGE) of 32 isolates revealed 14 XbaI-PFGE groups (I to XIV) of similarity >85%, with 23 (72%) isolates grouped in five clusters. Some isolates from different districts presented a high clonal relatedness. Thus, PFGE group VIII clustered eleven strains from nine different districts. The broad range of PFGE subtypes found in this study demonstrates the natural occurrence of many genetic variants among STEC O157:H7 spread in Lima.

Animals↗

PubMed2006

Frequency and predictors of symptomatic intracerebral hemorrhage in patients with ischemic stroke treated with recombinant tissue plasminogen activator outside clinical trials.

BACKGROUND: To determine the frequency and predictors of symptomatic intracerebral hemorrhage (SICH) in patients treated with recombinant tissue plasminogen activator (rt-PA). METHODS: We reviewed the databases of 7 tertiary hospitals that treated ischemic stroke patients with intravenous rt-PA. We recorded demographic data, vascular risk factors, time between onset and treatment, dose, the NIHSS score, body temperature, blood pressure, platelet count, blood glucose, antiplatelet treatment, and CT data. We also registered the study protocol used for treatment and deviations from the accepted protocol. A control CT was performed on all patients. SICH was diagnosed if a parenchymal hematoma was detected within the 36 h after rt-PA and was associated with an increase of > or =4 in the NIHSS score. Bivariate analyses were performed followed by a logistic regression analysis. RESULTS: A total of 347 patients were studied, whose mean age was 68 +/- 10.9 years; 56% were men. Thirty-two patients (9.2%) exhibited a parenchymal hematoma, and 8 patients (2.3%) suffered a SICH. Patients with SICH had a higher frequency of previous transient ischemic attack (p = 0.04), early signs of ischemia (p = 0.003), hyperdense arterial sign (p = 0.008), and deviations (p = 0.002). Early signs of ischemia (OR 8.5, 95% CI 1.6-45.4, p = 0.01) and deviation from the protocol (OR 11.1, 95% CI 2.4-50, p = 0.002) were independent predictors of SICH. CONCLUSIONS: SICH is infrequent in patients with ischemic stroke treated with rt-PA outside of a clinical trial. Its frequency increases in the presence of early signs of ischemia on the non-contrast CT scan and deviations from the recommended protocol.

Aged↗

PubMed2006

High blood pressure and inflammation are associated with poor prognosis in lacunar infarctions.

UNLABELLED: Lacunar infarction has long been considered to be associated with good prognosis, however a significant percentage of these patients remain functionally dependent. In this study we sought to investigate the factors associated with poor outcome in patients with lacunar infarction. SUBJECTS AND METHODS: We have performed a secondary study in 113 patients with lacunar infarctions admitted within the first 24 h of symptom onset (mean age 70 years, 57.5% men). Blood pressure, body temperature, serum glucose levels, neurotransmitters and pro-inflammatory markers were measured at admission and during the first 72 h. Stroke severity was assessed by the Canadian Stroke Scale (CSS). Neuroimaging evaluation was performed at admission and between days 4 and 7. Poor functional outcome was considered as a Barthel index <85 at 3 months. RESULTS: 36 patients (31.9%) had poor outcome. Older age (p = 0.009), history of hypertension (p = 0.005), higher body temperature (p < 0.0001), systolic blood pressure (SBP) (p = 0.010), serum glucose (p = 0.002) and interleukin-6 (IL-6) (p < 0.0001) levels, as well as lower CSS score at admission (p < 0.0001) were all predictive factors of poor outcome in bivariate analyses. SBP at admission (OR 2.07, CI 95% 1.04-3.28, p = 0.015) was the only clinical predictor on multivariate analysis. When the logistic model was further adjusted for biomarkers of inflammation and excitotoxicity, IL-6 levels (OR 1.09, CI 95% 1.01-1.26, p = 0.003), but not SBP, was independently associated with poor outcome. This association persisted even after adjusting for potential predictors recorded during the first 72 h of hospitalization. CONCLUSION: High SBP and IL-6 levels on admission may predict poor outcome in patients with lacunar infarction.

Aged↗

PubMed2006

Vascular protection in brain ischemia.

Vascular damage occurring after cerebral ischemia may lead to a worse outcome in patients with ischemic stroke, as it facilitates edema formation and hemorrhagic transformation. There are several phases in the development of vascular injury (acute, subacute and chronic) and different mediators act in each one. Therapeutic options to avoid vascular injury must be focused on acting in each phase. However, even though experimental studies have demonstrated the benefit of therapeutic interventions both in the acute and chronic phases of cerebral ischemia, only the chronic phase offers a therapeutic window sufficiently wide enough to provide vascular protection in clinical practice. Several drugs including erythropoietin and HMG-CoA reductase inhibitors (statins), antihypertensive (angiotensin modulators), antibiotics (minocycline) and antihyperglycemic drugs (thiazolidinediones) have been proved to provide vascular protection in patients with ischemic stroke. Anti-inflammatory, antioxidant, and antiapoptotic actions are responsible for the vascular protective effect related to these drugs.

Angiotensin II Type 1 Receptor Blockers↗

PubMed2006

Ischemic preconditioning: a novel target for neuroprotective therapy.

Ischemic preconditioning involves a brief exposure to ischemia in order to develop a tolerance to injurious effects of prolonged ischemia. The molecular mechanisms of neuroprotection that lead to ischemic tolerance are not yet completely understood. However, it seems that two distinct phases are involved. Firstly, a cellular defense function against ischemia may be developed by the mechanisms inherent to neurons such as posttranslational modification of proteins or expression of new proteins via a signal transduction system to the nucleus. Secondly, a stress response and synthesis of stress proteins (heat shock proteins) may be activated. These mechanisms are mediated by chaperones. The objective of ischemic preconditioning research is to identify the underlying endogenous protective cellular receptors and signaling cascades, with the long-term goal of allowing therapeutic augmentation of the endogenous protective mechanisms in cerebral ischemia and possibly development of new neuroprotective strategies for ischemic stroke treatment.

Adenosine Triphosphate↗

PubMed2006

Non-pharmacological neuroprotection: role of emergency stroke management.

Acute stroke should be considered a medical emergency, where actions taken in the first hours are fundamental for achieving recovery of the damaged cerebral tissue and a better prognosis for the patient. Recanalization and neuroprotective treatment has been used with mixed results. The effectiveness observed in the first hours with thrombolytic drug treatment is only applicable to a small percentage of patients, and attempts to widen this treatment window have not yet proved fruitful. Pharmacological neuroprotective treatment has not yet demonstrated the clinical effectiveness observed in experimental models. The concept of neuroprotection in cerebral ischemia also involves a series of mechanisms that take place at the cerebral level following vascular occlusion. In this context, it should be borne in mind that a series of physiological functions usually involved in the cerebral metabolism (control of blood pressure, of temperature, of glycemia and of arterial oxygen saturation) play a key role in modulation of the ischemic process. Changes in the control of these mechanisms may aggravate the process of cerebral damage in the first hours of ischemic stroke. In this work we review the prognostic importance of the main mechanisms that may influence the acute phase of cerebral ischemic stroke, as well as their therapeutic management and control in the clinical situation.

Antihypertensive Agents↗

PubMed2006

Serotypes, virulence genes, and PFGE profiles of Escherichia coli isolated from pigs with postweaning diarrhoea in Slovakia.

BACKGROUND: Postweaning diarrhoea (PWD) in pigs is usually the main infectious problem of large-scale farms and is responsible for significant losses worldwide. The disease is caused mainly by enterotoxigenic E. coli (ETEC) and Shiga-toxin producing E. coli (STEC). In this study a total of 101 E. coli isolated from pigs with PWD in Slovakia were characterized using phenotypic and genotypic methods. RESULTS: These 101 isolates belonged to 40 O:H serotypes. However, 57% of the isolates belonged to only six serotypes (O9:H51, O147:H-, O149:H10, O163:H-, ONT:H-, and ONT:H4), including two new serotypes (O163:H- and ONT:H4) not previously found among porcine ETEC and STEC isolated in other countries. Genes for EAST1, STb, STa, LT and Stx2e toxins were identified in 64%, 46%, 26%, 20%, and 5% of isolates, respectively. PCR showed that 35% of isolates carried genes for F18 colonization factor, and further analyzed by restriction endonuclease revealed that all of them were F18ac. Genes for F4 (K88), F6 (P987), F17, F5 (K99), F41, and intimin (eae gene) adhesins were detected in 19 %, 5%, 3%, 0.9%, 0.9%, and 0.9% of the isolates, respectively. The study of genetic diversity, carried out by PFGE of 46 representative ETEC and STEC isolates, revealed 36 distinct restriction profiles clustered in eight groups. Isolates of the same serotype were placed together in the dendrogram, but high degree of polymorphism among certain serotypes was detected. CONCLUSION: Seropathotype O149:H10 LT/STb/EAST1/F4 (14 isolates) was the most commonly detected followed by O163:H- EAST1/F18 (six isolates), and ONT:H4 STa/STb/Stx2e/F18 (five isolates). Interestingly, this study shows that two new serotypes (O163:H- and ONT:H4) have emerged as pig pathogens in Slovakia. Furthermore, our results show that there is a high genetic variation mainly among ETEC of O149:H10 serotype.

Journal Article↗

PubMed2006

A polymorphism in the EAAT2 promoter is associated with higher glutamate concentrations and higher frequency of progressing stroke.

It remains unclear why some individuals are susceptible to excitotoxicity after stroke. A possible explanation is impaired glutamate uptake. We have found a highly prevalent polymorphism in the promoter of the glutamate transporter EAAT2 gene that abolishes a putative regulatory site for activator protein-2 (AP-2) and creates a new consensus binding site for the repressor transcription factor GC-binding factor 2 (GCF2). The mutant genotype is associated with increased plasma glutamate concentrations and with a higher frequency of early neurological worsening in human stroke. After transfection into astrocytes, the mutant promoter was not activated by AP-2 and was effectively repressed by GCF2, and its activity in the presence of GCF2 was reduced when compared with the AP-2-cotransfected wild-type promoter. We also show that GCF2 is expressed in ischemic rat brain, suggesting that decreased glutamate uptake occurs in individuals carrying the mutation after stroke. These findings may explain individual susceptibility to excitotoxic damage after stroke as well as the failure of glutamate antagonists in those patients without this polymorphism.

Aged↗

PubMed2006

Typing of intimin (eae) genes from enteropathogenic Escherichia coli (EPEC) isolated from children with diarrhoea in Montevideo, Uruguay: identification of two novel intimin variants (muB and xiR/beta2B).

A total of 71 enteropathogenic Escherichia coli (EPEC) strains isolated from children with diarrhoea in Montevideo, Uruguay, were characterized in this study. PCR showed that 57 isolates carried eae and bfp genes (typical EPEC strains), and 14 possessed only the eae gene (atypical EPEC strains). These EPEC strains belonged to 21 O : H serotypes, including eight novel serotypes not previously reported among human EPEC in other studies. However, 72% belonged to only four serotypes: O55:H- (six strains), O111:H2 (13 strains), O111:H- (14 strains) and O119:H6 (18 strains). Nine intimin types, namely, alpha1 (two O142 strains), beta1 (29 strains, including 13 O111:H2 and 14 O111:H-), gamma1 (three O55:H- strains), theta (five strains, including three strains with H40 antigen), kappa (two strains), epsilon1 (one strain), lambda (one strain), muB (six strains of serotypes O55:H51 and O55:H-) and xiR/beta2B (22 strains, including 18 O119:H6) were detected among the 71 EPEC strains. The authors have identified two novel intimin genes (muB and xiR/beta2B) in typical EPEC strains of serotypes O55:H51/H- and O119:H6/H-. The complete nucleotide sequences of the novel muB and xiR/beta2 variant genes were determined. PFGE typing after XbaI DNA digestion was performed on 44 representative EPEC strains. Genomic DNA fingerprinting revealed 44 distinct restriction patterns and the strains were clustered in 12 groups. Only 15 strains clustered in six groups of closely related (similarity>85%) PFGE patterns, suggesting the prevailing clonal diversity among EPEC strains isolated from children with diarrhoea in Montevideo.

Adhesins, Bacterial↗

PubMed2006

Common virulence factors and genetic relationships between O18:K1:H7 Escherichia coli isolates of human and avian origin.

Extraintestinal pathogenic (ExPEC) Escherichia coli strains of serotype O18:K1:H7 are mainly responsible for neonatal meningitis and sepsis in humans and belong to a limited number of closely related clones. The same serotype is also frequently isolated from the extraintestinal lesions of colibacillosis in poultry, but it is not well known to what extent human and avian strains of this particular serotype are related. Twenty-two ExPEC isolates of human origin and 33 isolates of avian origin were compared on the basis of their virulence determinants, lethality for chicks, pulsed-field gel electrophoresis (PFGE) patterns, and classification in the main phylogenetic groups. Both avian and human isolates were lethal for chicks and harbored similar virulence genotypes. A major virulence pattern, identified in 75% of the isolates, was characterized by the presence of F1 variant fimbriae; S fimbriae; IbeA; the aerobactin system; and genomic fragments A9, A12, D1, D7, D10, and D11 and by the absence of P fimbriae, F1C fimbriae, Afa adhesin, and CNF1. All but one of the avian and human isolates also belonged to major phylogenetic group B2. However, various subclonal populations could be distinguished by PFGE in relation to animal species and geographical origin. These results demonstrate that very closely related clones can be recovered from extraintestinal infections in humans and chickens and suggest that avian pathogenic E. coli isolates of serotype O18:K1:H7 are potential human pathogens.

Animals↗

PubMed2006

Serotypes, virulence genes, and PFGE patterns of enteropathogenic Escherichia coli isolated from Cuban pigs with diarrhea.

Thirty-six enteropathogenic Escherichia coli strains isolated from Cuban pigs with diarrhea were serotyped and screened by PCR for the presence of virulence genes. The 36 isolates belonged to 11 O serogroups and 14 O:H serotypes, with 53% of the isolates belonging to only two serotypes: O141:H- (13 isolates) and O157:H19 (6 isolates). Genes coding for STb, STa, VT2e, and LT toxins were identified in 69, 61, 53, and 6% of the isolates, respectively. The most prevalent fimbrial adhesin was F18, detected in 22 (61%) isolates. The gene encoding F6 (P987) colonization factor was identified in three (8%) isolates. None of the 36 isolates assayed contained genes encoding F4 (K88), F5 (K99), or F41. The seropathotype O141:H-:STa/STb/VT2e/F18 (13 isolates) was the most frequently detected, followed by O157:H19:VT2e/F18 (5 isolates). A genetic diversity study, carried out by pulsed-field gel electrophoresis (PFGE) of 24 representative isolates, revealed 21 distinct restriction patterns clustered in 18 groups (I-XVIII). Isolates of the same serotype were placed together in a dendrogram, but isolates of serotype O157:H19 showed a high degree of polymorphism. The results of this study demonstrate the presence in Cuba of different clusters among one of the most prevalent serotypes isolated from pigs with diarrhea. Further experiments are needed to determine whether some of these clusters have appeared recently; if so, their evolution, as well as their possible association with pathogenicity in farms should be studied.

Adhesins, Bacterial↗

PubMed2006

Identification of two new intimin types in atypical enteropathogenic Escherichia coli.

Stool specimens of patients with diarrhea or other gastrointestinal alterations who were admitted to Xeral-Calde Hospital (Lugo, Spain) were analyzed for the prevalence of typical and atypical enteropathogenic Escherichia coli (EPEC). Atypical EPEC strains (eae+ bfp-) were detected in 105 (5.2%) of 2015 patients, whereas typical EPEC strains (eae+ bfp+) were identified in only five (0.2%) patients. Atypical EPEC strains were (after Salmonella) the second most frequently recovered enteropathogenic bacteria. In this study, 110 EPEC strains were characterized. The strains belonged to 43 O serogroups and 69 O:H serotypes, including 44 new serotypes not previously reported among human EPEC. However, 29% were of one of three serogroups (O26, O51, and O145) and 33% belonged to eight serotypes (O10:H-, O26:H11, O26:H-, O51:H49, O123:H19, O128:H2, O145:H28, and O145:H-). Only 14 (13%) could be assigned to classical EPEC serotypes. Fifteen intimin types, namely, alpha1 (6 strains), alpha2 (4 strains), beta1 (34 strains), xiR/b2 (6 strains), gamma1 (13 strains), gamma2/q (16 strains), delta/k (5 strains), epsilon1 (9 strains), nuR/e2 (5 strains), zeta (6 strains), iota1 (1 strain), muR/iota2 (1 strain), nuB (1 strain), xiB (1 strain), and o (2 strains), were detected among the 110 EPEC strains, but none of the strains was positive for intimin types mu1, mu2, lambda, or muB. In addition, in atypical EPEC strains of serotypes O10:H-, O84:H-, and O129:H-, two new intimin genes (eae-nuB and eae-o) were identified. These genes showed less than 95% nucleotide sequence identity with existing intimin types. Phylogenetic analysis revealed six groups of closely related intimin genes: (i) alpha1, alpha2, zeta, nuB, and o; (ii) iota1 and muR/iota2; (iii) beta1, xiR/beta2B, delta/beta2O, and kappa; (iv) epsilon1, xiB, eta1,eta2, and nuR/epsilon2; (v) gamma1, muB, gamma2, and theta; and (vi) lambda. These results indicate that atypical EPEC strains belonging to large number of serotypes and with different intimin types might be frequently isolated from human clinical stool samples in Spain.

Adhesins, Bacterial↗

PubMed2005

STEC-EPEC oligonucleotide microarray: a new tool for typing genetic variants of the LEE pathogenicity island of human and animal Shiga toxin-producing Escherichia coli (STEC) and enteropathogenic E. coli (EPEC) strains.

BACKGROUND: Shiga toxin-producing Escherichia coli (STEC) and enteropathogenic E. coli (EPEC) are important emerging pathogens that can cause a severe and sometimes fatal illness. Differentiation of eae, tir, espA, espD, and espB gene variants of the locus of enterocyte effacement (LEE) pathogenicity island represents an important tool for typing in routine diagnostics as well as in pathogenesis, epidemiologic, clonal, and immunologic studies. METHODS: Type-specific oligonucleotide microarrays and a PCR scheme were designed and constructed for the detection and typing of genetic variants of the LEE genes. Oligonucleotide probes were tested for their specificity against the corresponding type strain by microarray hybridization using fluorescent DNA, either PCR-amplified (single, multiplex, long-range), chromosomal, or amplified chromosomal DNA. RESULTS: The PCR scheme and the oligonucleotide microarray allowed us to distinguish 16 variants (alpha1, alpha2, beta1, beta2, gamma1, gamma2/theta, delta/kappa, epsilon, zeta, eta, iota, lambda, mu, nu, xi, omicron) of the eae gene, 4 variants (alpha1, beta1, gamma1, gamma2/theta) of the tir gene, 4 variants (alpha1, beta1, beta2, gamma1) of the espA gene, 3 variants (alpha1, beta1, gamma1) of the espB gene, and 3 variants (alpha1, beta1, gamma1) of the espD gene. We found a total of 12 different combinations of tir, espA, espB, and espD genes among the 25 typed strains. CONCLUSIONS: The PCR scheme and the oligonucleotide microarray described are effective tools to rapidly screen multiple virulence genes and their variants in E. coli strains isolated from human and animal infections. The results demonstrate the great genetic diversity among LEE genes of human and animal STEC and EPEC strains.

Animals↗

PubMed2005

Platelets, inflammation, and atherothrombotic neurovascular disease: the role of endothelial dysfunction.

The vascular endothelium is an indispensable organ in the regulation of tonicity and vascular homeostasis. Endothelial dysfunction is a marker of atherosclerosis and contributes to the atherogenic process and the development of atherothrombotic complications. Endothelial dysfunction is the common meeting point among factors for vascular risk and launches complex cellular and biochemical interactions that are characterized by oxidative stress and an intense inflammatory response. The strategic importance of the concept of endothelial dysfunction arises from the following facts: its diagnosis is simple, it allows the identification of asymptomatic arteriosclerotic subjects with a high risk of developing atherothrombotic complications, it is reversible, and it responds to various therapeutic strategies.

Animals↗

PubMed2005

A large-scale screen in S. pombe identifies seven novel genes required for critical meiotic events.

Meiosis is a specialized form of cell division by which sexually reproducing diploid organisms generate haploid gametes. During a long prophase, telomeres cluster into the bouquet configuration to aid chromosome pairing, and DNA replication is followed by high levels of recombination between homologous chromosomes (homologs). This recombination is important for the reductional segregation of homologs at the first meiotic division; without further replication, a second meiotic division yields haploid nuclei. In the fission yeast Schizosaccharomyces pombe, we have deleted 175 meiotically upregulated genes and found seven genes not previously reported to be critical for meiotic events. Three mutants (rec24, rec25, and rec27) had strongly reduced meiosis-specific DNA double-strand breakage and recombination. One mutant (tht2) was deficient in karyogamy, and two (bqt1 and bqt2) were deficient in telomere clustering, explaining their defects in recombination and segregation. The moa1 mutant was delayed in premeiotic S phase progression and nuclear divisions. Further analysis of these mutants will help elucidate the complex machinery governing the special behavior of meiotic chromosomes.

Chromosome Segregation↗

PubMed2005

The prediction of malignant cerebral infarction by molecular brain barrier disruption markers.

BACKGROUND AND PURPOSE: Space-occupying brain edema is a life-threatening complication in patients with large hemispheric stroke. The aim of the study was to determine whether molecular markers of endothelial damage may help to predict secondary brain edema and, secondly, to identify patients who could benefit from aggressive therapies such as decompressive hemicraniectomy or hypothermia. METHODS: We studied 40 consecutive patients with malignant middle cerebral artery (MCA) infarction and 35 controls with massive MCA infarctions <70 years of age and matched by stroke severity on admission. Cranial computed tomography (CT) was performed at entry and repeated between days 4 and 7, or earlier if there was neurological worsening. Malignant MCA (m-MCA) infarction was diagnosed when follow-up CT detected a more than two-thirds space-occupying MCA infarction with midline shift, compression of the basal cisterns, and neurological deterioration. Plasma concentrations of glutamate, glycine, gamma-aminobutyric acid, interleukin-6 (IL-6), IL-10, tumor necrosis factor-alpha, matrix metalloproteinase-9 (MMP-9), and cellular-fibronectin (c-Fn) were determined in blood samples obtained at admission. RESULTS: Mean time from stroke onset to blood sampling was 6.3+/-4.8 in m-MCA and 7.7+/-6.0 hours in the control group (P=0.63). Baseline characteristics were comparable in both groups. c-Fn and MMP-9 levels were significantly higher in patients with m-MCA than in controls (all P<0.001). c-Fn >16.6 microg/mL had the highest sensitivity (90%), specificity (100%), and negative and positive predictive values (89% and 100%, respectively) for the prediction of m-MCA infarction. CONCLUSIONS: A plasma c-Fn concentration >16.6 microg/mL at admission is associated with the development of m-MCA infarction with high sensitivity and specificity, suggesting that c-Fn might be useful in therapeutic decision making.

Aged↗

PubMed2005

Serotypes, intimin variants and other virulence factors of eae positive Escherichia coli strains isolated from healthy cattle in Switzerland. Identification of a new intimin variant gene (eae-eta2).

BACKGROUND: Enteropathogenic Escherichia coli (EPEC) and Shigatoxin-producing Escherichia coli (STEC) share the ability to introduce attaching-and-effacing (A/E) lesions on intestinal cells. The genetic determinants for the production of A/E lesions are located on the locus of enterocyte effacement (LEE), a pathogenicity island that also contains the genes encoding intimin (eae). This study reports information on the occurrence of eae positive E. coli carried by healthy cattle at the point of slaughter, and on serotypes, intimin variants, and further virulence factors of isolated EPEC and STEC strains. RESULTS: Of 51 eae positive bovine E. coli strains, 59% were classified as EPEC and 41% as STEC. EPEC strains belonged to 18 O:H serotypes, six strains to typical EPEC serogroups. EPEC strains harbored a variety of intimin variants with eae-beta1 being most frequently found. Moreover, nine EPEC strains harbored astA (EAST1), seven bfpA (bundlin), and only one strain was positive for the EAF plasmid. We have identified a new intimin gene (eta2) in three bovine bfpA and astA-positive EPEC strains of serotype ONT:H45. STEC strains belonged to seven O:H serotypes with one serotype (O103:H2) accounting for 48% of the strains. The majority of bovine STEC strains (90%) belonged to five serotypes previously reported in association with hemolytic uremic syndrom (HUS), including one O157:H7 STEC strain. STEC strains harbored four intimin variants with eae-epsilon1 and eae-gamma1 being most frequently found. Moreover, the majority of STEC strains carried only stx1 genes (13 strains), and was positive for ehxA (18 strains) encoding for Enterohemolysin. Four STEC strains showed a virulence pattern characteristic of highly virulent human strains (stx2 and eae positive). CONCLUSION: Our data confirm that ruminants are an important source of serologically and genetically diverse intimin-harboring E. coli strains. Moreover, cattle have not only to be considered as important asymptomatic carriers of O157 STEC but can also be a reservoir of EPEC and eae positive non-O157 STEC, which are described in association with human diseases.

Adhesins, Bacterial↗

PubMed2005

Increased plasma levels of 15-deoxyDelta prostaglandin J2 are associated with good outcome in acute atherothrombotic ischemic stroke.

BACKGROUND AND PURPOSE: The 15-deoxyDelta prostaglandin J2 (15-dPGJ2) is an anti-inflammatory prostaglandin that has been proposed to be the endogenous ligand of peroxisome proliferator-activated receptor-gamma (PPARgamma), a nuclear receptor that can exert potent anti-inflammatory actions by repressing inflammatory genes when activated. It has been suggested that 15-dPGJ2 could be beneficial in neurological disorders in which inflammation contributes to cell death such as stroke. METHODS: We investigated the relationship between plasma levels of 15-dPGJ2 and early neurological deterioration (END), infarct volume, and neurologic outcome in 552 patients with an acute stroke admitted within 24 hours after symptoms onset. RESULTS: Median [quartiles] plasma 15-dPGJ2 levels on admission were significantly higher in patients than in controls (60.5 [11.2 to 109.4] versus 5.0 [3.8 to 7.2] pg/mL; P<0.0001). Levels of this prostaglandin were also significantly higher in patients with vascular risk factors (history of hypertension or diabetes) and with atherothrombotic infarcts (113.9 [81.6 to 139.7] pg/mL), than in those with lacunar (58.7 [32.7 to 86.2] pg/mL), cardioembolic (12.1 [6.5 to 39.2] pg/mL), or undetermined origin infarcts (11.4 [5.6 to 24.3] pg/mL) (P<0.0001). In the subgroup of patients with atherothrombotic infarcts, the adjusted odds ratio of END and poor outcome for 1 pg/mL increase in 15-dPGJ2 were 0.95 (95% CI, 0.94 to 0.97) and 0.97 (95% CI, 0.96 to 0.98), respectively. In a generalized linear model, by 1 U increase in 15-dPGJ2, there was a reduction of 0.47 mL (95% CI, 0.32 to 0.63) in the mean estimated infarct volume. CONCLUSIONS: Increased plasma 15-dPGJ2 concentration is associated with good early and late neurological outcome and smaller infarct volume. These findings suggest a neuroprotective effect of 15-dPGJ2 in atherothrombotic ischemic stroke.

Acute Disease↗