Dissection of the role of pili and type 2 and 3 secretion systems in adherence and biofilm formation of an atypical enteropathogenic escherichia coli strain

Atypical enteropathogenic Escherichia coli (aEPEC) strains are diarrheal pathogens that lack bundle-forming pilus production but possess the virulence-associated locus of enterocyte effacement. aEPEC strain 1551-2 produces localized adherence (LA) on HeLa cells; however, its isogenic intimin (eae) mutant produces a diffuse-adherence (DA) pattern. In this study, we aimed to identify the DA-associated adhesin of the 1551-2 eae mutant. Electron microscopy of 1551-2 identified rigid rod-like pili composed of an 18-kDa protein, which was identified as the major pilin subunit of type 1 pilus (T1P) by mass spectrometry analysis. Deletion of fimA in 1551-2 affected biofilm formation but had no effect on adherence properties. Analysis of secreted proteins in supernatants of this strain identified a 150-kDa protein corresponding to SslE, a type 2 secreted protein that was recently reported to be involved in biofilm formation of rabbit and human EPEC strains. However, neither adherence nor biofilm formation was affected in a 1551-2 sslE mutant. We then investigated the role of the EspA filament associated with the type 3 secretion system (T3SS) in DA by generating a double eae espA mutant. This strain was no longer adherent, strongly suggesting that the T3SS translocon is the DA adhesin. In agreement with these results, specific anti-EspA antibodies blocked adherence of the 1551-2 eae mutant. Our data support a role for intimin in LA, for the T3SS translocon in DA, and for T1P in biofilm formation, all of which may act in concert to facilitate host intestinal colonization by aEPEC strains. ©2013, American Society for Microbiology.

Prevention of repeated episodes of type 2 reaction of leprosy with the use of thalidomide 100 mg/day

BACKGROUND: Leprosy can have its course interrupted by type 1 and 2 reactional episodes, the last named of erythema nodosum leprosum (ENL). Thalidomide has been the medication of choice for the control of ENL episodes since 1965. OBJECTIVES: These episodes can repeat and cause damages to the patient. In order to prevent these episodes, an extra dose of 100 mg/day thalidomide was used during six months, followed by a follow-up period of six more months after thalidomide discontinuation. METHODS: We included 42 patients with multibacillary (MB) leprosy who had episodes of ENL. They were male and female patients aged between 18 and 84 years. RESULTS: Of the 42 patients, 39 (92.85%) had the lepromatous form and three (7.15%) had the borderline form. We found that 100% of patients had no reactional episode during the use of the drug. During the follow-up period after thalidomide discontinuation, 33 (78.57%) patients had no reactional episode and nine (21.43%), all of them with the lepromatous form, had mild episodes, which were controlled using non-steroidal anti-inflammatory. There were no thalidomide-related side effects. CONCLUSION: A maintenance dose of 100 mg/day of thalidomide showed to be effective to prevent repeated type 2 reactional episodes of ENL.

Subgingival biodiversity in subjects with uncontrolled type-2 diabetes and chronic periodontitis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Synthesis and evaluation of novel dapsone-thalidomide hybrids for the treatment of type 2 leprosy reactions

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Therapeutic interventions to reduce the risk of progression from prediabetes to type 2 diabetes mellitus

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Type-2 diabetes mellitus and the frequency of the G22A polymorphism of the adenosine deaminase gene in a mixed population in Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Type 2 Diabetes Elicits Lower Nitric Oxide, Bradykinin Concentration and Kallikrein Activity Together with Higher DesArg(9)-BK and Reduced Post-Exercise Hypotension Compared to Non-Diabetic Condition

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Elevated micronucleus frequency in patients with type 2 diabetes, dyslipidemia and periodontitis

The over-production of reactive oxygen species (ROS) can cause oxidative damage to a large number of molecules, including DNA, and has been associated with the pathogenesis of several disorders, such as diabetes mellitus (DM), dyslipidemia and periodontitis (PD). We hypothesise that the presence of these diseases could proportionally increase the DNA damage. The aim of this study was to assess the micronucleus frequency (MNF), as a biomarker for DNA damage, in individuals with type 2 DM, dyslipidemia and PD. One hundred and fifty patients were divided into five groups based upon diabetic, dyslipidemic and periodontal status (Group 1 - poor controlled DM with dyslipidemia and PD; Group 2 - well-controlled DM with dyslipidemia and PD; Group 3 - without DM with dyslipidemia and PD; Group 4 - without DM, without dyslipidemia and with PD; and Group 5 - without DM, dyslipidemia and PD). Blood analyses were carried out for fasting plasma glucose, HbA1c and lipid profile. Periodontal examinations were performed, and venous blood was collected and processed for micronucleus (MN) assay. The frequency of micronuclei was evaluated by cell culture cytokinesis-block MN assay. The general characteristics of each group were described by the mean and standard deviation and the data were submitted to the Mann-Whitney, Kruskal-Wallis, Multiple Logistic Regression and Spearman tests. The Groups 1, 2 and 3 were similarly dyslipidemic presenting increased levels of total cholesterol, low density lipoprotein cholesterol and triglycerides. Periodontal tissue destruction and local inflammation were significantly more severe in diabetics, particularly in Group 1. Frequency of bi-nucleated cells with MN and MNF, as well as nucleoplasmic bridges, were significantly higher for poor controlled diabetics with dyslipidemia and PD in comparison with those systemically healthy, even after adjusting for age, and considering Bonferroni's correction. Elevated frequency of micronuclei was found in patients affected by type 2 diabetes, dyslipidemia and PD. This result suggests that these three pathologies occurring simultaneously promote an additional role to produce DNA impairment. In addition, the micronuclei assay was useful as a biomarker for DNA damage in individuals with chronic degenerative diseases.

Increased Expression of Angiotensin II Type 2 Receptors in the Solitary-Vagal Complex Blunts Renovascular Hypertension

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Angiotensin converting enzyme polymorphism in type 2 diabetes mellitus

This study was undertaken to assess the frequency of angiotensin converting enzyme (ACE) insertion/deletion (I/D) polymorphism in patients with type 2 diabetes mellitus. A total of 162 patients with type 2 diabetes and 160 individuals without this disease were analyzed. From the diabetes group, 81 patients with cardiovascular risk (according to American Diabetes Association parameters) were selected to form another subgroup. For polymorphism identification, two polymerase chain reactions were performed: one reaction to identify all genotypes and a second one to confirm the presence of the I allele. The observed genotype frequencies were as follows: diabetes group I/I (19.1%), I/D (52.5%), D/D (28.4%); control group I/I (12.5%), I/D (55.6%), D/D (31.9%); and diabetes with cardiovascular risk group I/I (16.0%), I/ D (59.3%), D/D (24.7%). No statistically significant difference was observed between the allelic and genotypic frequencies in the analyzed groups. Previous studies reported an association between the D allele and type 2 diabetes in Caucasian and East Asian populations. However, in mixed populations, such as those found in Brazil, such an association was not found. This fact does not discard the need for more studies on the frequencies of this polymorphism in the Brazilian population and the associations with risk factors, which can compromise the quality of life of diabetes patients

Zinc supplementation for the prevention of type 2 diabetes mellitus in adults with insulin resistance

BackgroundDiabetes is associated with long-term damage, dysfunction and failure of various organs, especially the eyes, kidneys, nerves, heart and blood vessels. The risk of developing type 2 diabetes increases with age, obesity and lack of physical activity. Insulin resistance is a fundamental aspect of the aetiology of type 2 diabetes. Insulin resistance has been shown to be associated with atherosclerosis, dyslipidaemia, glucose intolerance, hyperuricaemia, hypertension and polycystic ovary syndrome. The mineral zinc plays a key role in the synthesis and action of insulin, both physiologically and in diabetes mellitus. Zinc seems to stimulate insulin action and insulin receptor tyrosine kinase activity.ObjectivesTo assess the effects of zinc supplementation for the prevention of type 2 diabetes mellitus in adults with insulin resistance.Search methodsThis review is an update of a previous Cochrane systematic review published in 2007. We searched the Cochrane Library (2015, Issue 3), MEDLINE, EMBASE, LILACS and the ICTRP trial register (frominception toMarch 2015). There were no language restrictions. We conducted citation searches and screened reference lists of included studies.Selection criteriaWe included studies if they had a randomised or quasi-randomised design and if they investigated zinc supplementation compared with placebo or no intervention in adults with insulin resistance living in the community.Data collection and analysisTwo review authors selected relevant trials, assessed risk of bias and extracted data.Main resultsWe included three trials with a total of 128 participants in this review. The duration of zinc supplementation ranged between four and 12 weeks. Risk of bias was unclear for most studies regarding selection bias (random sequence generation, allocation concealment) and detection bias (blinding of outcome assessment). No study reported on our key outcome measures (incidence of type 2 diabetes mellitus, adverse events, health-related quality of life, all-cause mortality, diabetic complications, socioeconomic effects). Evaluation of insulin resistance as measured by the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) showed neutral effects when comparing zinc supplementation with control (two trials; 114 participants). There were neutral effects for trials comparing zinc supplementation with placebo for total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol and triglycerides (2 studies, 70 participants). The one trial comparing zinc supplementation with exercise also showed neutral effects for total cholesterol, HDL and LDL cholesterol, and a mean difference in triglycerides of -30 mg/dL (95% confidence interval (CI) -49 to -10) in favour of zinc supplementation (53 participants). Various surrogate laboratory parameters were also analysed in the included trials.Authors'conclusionsThere is currently no evidence on which to base the use of zinc supplementation for the prevention of type 2 diabetes mellitus. Future trials should investigate patient-important outcome measures such as incidence of type 2 diabetes mellitus, health-related quality of life, diabetic complications, all-cause mortality and socioeconomic effects.

Association of a Large Panel of Cytokine Gene Polymorphisms with Complications and Comorbidities in Type 2 Diabetes Patients

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Cardiovascular effects of chronically increasing angiotensin II type 2 receptor expression in the nucleus of the solitary tract

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)