Productionof poly(L-CO-D,L LacticAcid) porous fibers by electrospinning

The production of porous scaffolds has been widely investigated by the scientific community due to its suitability for tissue engineering. Among techniques that allow the fabrication of porous materials, electrospinning is appealing for being robust and versatile. This research investigated the pore formation in poly (L-co-D,L lactic acid) fibers obtained by conventional electrospinning and the influence of chloroform as a single solvent on fiber morphology. Random and highly porous fibers with a mean diameter of 2.373 ± 0.564 µm were collected. Chloroform affects the fiber morphology, mainly for its fast evaporation and low density of charges. The solvent on the surface evaporates quickly, and the low stretch of the jet does not help the polymer to reorganize over the length of the fiber, forming pores. In conclusion, the low dielectric constant and boiling point of chloroform induce pores formation along the PLDLA fibers.

Activation of endogenous p53 by combined p19Arf gene transfer and nutlin-3 drug treatment modalities in the murine cell lines B16 and C6

<p>Abstract</p> <p>Background</p> <p>Reactivation of p53 by either gene transfer or pharmacologic approaches may compensate for loss of p19Arf or excess mdm2 expression, common events in melanoma and glioma. In our previous work, we constructed the pCLPG retroviral vector where transgene expression is controlled by p53 through a p53-responsive promoter. The use of this vector to introduce p19Arf into tumor cells that harbor p53wt should yield viral expression of p19Arf which, in turn, would activate the endogenous p53 and result in enhanced vector expression and tumor suppression. Since nutlin-3 can activate p53 by blocking its interaction with mdm2, we explored the possibility that the combination of p19Arf gene transfer and nutlin-3 drug treatment may provide an additive benefit in stimulating p53 function.</p> <p>Methods</p> <p>B16 (mouse melanoma) and C6 (rat glioma) cell lines, which harbor p53wt, were transduced with pCLPGp19 and these were additionally treated with nutlin-3 or the DNA damaging agent, doxorubicin. Viral expression was confirmed by Western, Northern and immunofluorescence assays. p53 function was assessed by reporter gene activity provided by a p53-responsive construct. Alterations in proliferation and viability were measured by colony formation, growth curve, cell cycle and MTT assays. In an animal model, B16 cells were treated with the pCLPGp19 virus and/or drugs before subcutaneous injection in C57BL/6 mice, observation of tumor progression and histopathologic analyses.</p> <p>Results</p> <p>Here we show that the functional activation of endogenous p53wt in B16 was particularly challenging, but accomplished when combined gene transfer and drug treatments were applied, resulting in increased transactivation by p53, marked cell cycle alteration and reduced viability in culture. In an animal model, B16 cells treated with both p19Arf and nutlin-3 yielded increased necrosis and decreased BrdU marking. In comparison, C6 cells were quite susceptible to either treatment, yet p53 was further activated by the combination of p19Arf and nutlin-3.</p> <p>Conclusions</p> <p>To the best of our knowledge, this is the first study to apply both p19Arf and nutlin-3 for the stimulation of p53 activity. These results support the notion that a p53 responsive vector may prove to be an interesting gene transfer tool, especially when combined with p53-activating agents, for the treatment of tumors that retain wild-type p53.</p

Metformin-induced lactic acidosis: a case series

<p>Abstract</p> <p>Introduction</p> <p>Unlike other agents used in the treatment of type 2 diabetes mellitus, metformin has been shown to reduce mortality in obese patients. It is therefore being increasingly used in higher doses. The major concern of many physicians is a possible risk of lactic acidosis. The reported frequency of metformin related lactic acidosis is 0.05 per 1000 patient-years; some authors advocate that this rate is equal in those patients not taking metformin.</p> <p>Case presentation</p> <p>We present two case reports of metformin-associated lactic acidosis. The first case is a 77 year old female with a past medical history of hypertension and type 2 diabetes mellitus who had recently been prescribed metformin (3 g/day), perindopril and acetylsalicylic acid. She was admitted to the emergency department two weeks later with abdominal pain and psychomotor agitation. Physical examination revealed only signs of poor perfusion. Laboratory evaluation revealed hyperkalemia, elevated creatinine and blood urea nitrogen and mild leukocytosis. Arterial blood gases showed severe lactic acidemia. She was admitted to the intensive care unit. Vasopressor and ventilatory support was initiated and continuous venovenous hemodiafiltration was instituted. Twenty-four hours later, full clinical recovery was observed, with return to a normal serum lactate level. The patient was discharged from the intensive care unit on the sixth day. The second patient is a 69 year old male with a past medical history of hypertension, type 2 diabetes mellitus and ischemic heart disease who was on metformin (4 g/day), glycazide, acetylsalicylic acid and isosorbide dinitrate. He was admitted to the emergency department in shock with extreme bradycardia. Initial evaluation revealed severe lactic acidosis and elevated creatinine and urea. The patient was admitted to the Intensive Care Unit and commenced on continuous venovenous hemodiafiltration in addition to other supportive measures. A progressive recovery was observed and he was discharged from the intensive care unit on the seventh day.</p> <p>Conclusion</p> <p>We present two case reports of severe lactic acidosis most probably associated with high doses of metformin in patients with no known contraindications for metformin prescription. In both patients no other condition was identified to cause such severe lactic acidosis. Although controversial, lactic acidosis should be considered in patients taking metformin.</p

Multicenter double blind trial of autologous bone marrow mononuclear cell transplantation through intracoronary injection post acute myocardium infarction – MiHeart/AMI study

Background: Myocardial infarction remains as a major cause of mortality worldwide and a high rate of survivors develop heart failure as a sequel, resulting in a high morbidity and elevated expenditures for health system resources. We have designed a multicenter trial to test for the efficacy of autologous bone marrow (ABM) mononuclear cell (MC) transplantation in this subgroup of patients. The main hypothesis to be tested is that treated patients will have a significantly higher ejection fraction (EF) improvement after 6 months than controls. Methods: A sample of 300 patients admitted with ST elevation acute myocardial infarction (STEMI) and left ventricle (LV) systolic dysfunction, and submitted to successful mechanical or chemical recanalization of the infarct-related coronary artery will be selected for inclusion and randomized to either treated or control group in a double blind manner. The former group will receive 100 x 106 MC suspended in saline with 5% autologous serum in the culprit vessel, while the latter will receive placebo (saline with 5% autologous serum). Implications: Many phase I/II clinical trials using cell therapy for STEMI have been reported, demonstrating that cell transplantation is safe and may lead to better preserved LV function. Patients with high risk to develop systolic dysfunction have the potential to benefit more. Larger randomized, double blind and controlled trials to test for the efficacy of cell therapies in patients with high risk for developing heart failure are required.Brazilian Ministry of Science and Technology (MCT)/The Financing Agency for Studies and Projects (FINEP

Sequential multiplex PCR assay for determining capsular serotypes of colonizing S. pneumoniae

Asymptomatic nasopharyngeal carriage represents an important biological marker for monitoring pneumococcal serotype distribution and evaluating vaccine effects. Serotype determination by conventional method (Quellung reaction) is technically and financially challenging. On the contrary, PCR-based serotyping represents a simple, economic and promising alternative method.Evaluation StudiesJournal ArticleResearch Support, Non-U.S. Gov'tSCOPUS: ar.jinfo:eu-repo/semantics/publishe

Leishmania donovani nucleoside hydrolase (NH36) Domains induce T-cell cytokine responses in human Visceral leishmaniasis

Development of immunoprotection against visceral leishmaniasis (VL) focused on the identification of antigens capable of inducing a Th1 immune response. Alternatively, antigens targeting the CD8 and T-regulatory responses are also relevant in VL pathogenesis and worthy of being included in a preventive human vaccine. We assessed in active and cured patients and VL asymptomatic subjects the clinical signs and cytokine responses to the Leishmania donovani nucleoside hydrolase NH36 antigen and its N-(F1), central (F2) and C-terminal (F3) domains. As markers of VL resistance, the F2 induced the highest levels of IFN-gamma, IL-1 beta, and TNF-a and, together with F1, the strongest secretion of IL-17, IL-6, and IL-10 in DTH+ and cured subjects. F2 also promoted the highest frequencies of CD3(+)CD4(+)IL-2(+)TNF-alpha-IFN-gamma(-), CD3(+)CD4(+)IL-2(+)TNF-alpha+IFN-gamma(-), CD3(+)CD4(+)IL-2(+)TNF-alpha-IFN-gamma(+), and CD3(+)CD4(+)IL-2(+)TNF-alpha+IFN-gamma(+) T cells in cured and asymptomatic subjects. Consistent with this, the IFN-gamma increase was correlated with decreased spleen (R = -0.428, P = 0.05) and liver sizes (R = -0.428, P = 0.05) and with increased hematocrit counts (R = 0.532, P = 0.015) in response to F1 domain, and with increased hematocrit (R = 0.512, P 0.02) and hemoglobin counts (R = 0.434, P = 0.05) in response to F2. Additionally, IL-17 increases were associated with decreased spleen and liver sizes in response to F1 (R = -0.595, P = 0.005) and F2 (R = -0.462, P = 0.04). Conversely, F1 and F3 increased the CD3(+)CD8(+)IL-2(+)TNF-alpha-IFN-gamma(-), CD3(+)CD8(+)IL-2(+)TNF-alpha+IFN-gamma(-), and CD3(+)CD8(+)IL-2(+)TNF-alpha+IFN-gamma(+) T cell frequencies of VL patients correlated with increased spleen and liver sizes and decreased hemoglobin and hematocrit values. Therefore, cure and acquired resistance to VL correlate with the CD4(+)-Th1 and Th-17 T-cell responses to F2 and F1 domains. Clinical VL outcomes, by contrast, correlate with CD8(+) T-cell responses against F3 and F1, potentially involved in control of the early infection. The in silico-predicted NH36 epitopes are conserved and bind to many HL-DR and HLA and B allotypes. No human vaccine against Leishmania is available thus far. In this investigation, we identified the NH36 domains and epitopes that induce CD4(+) and CD8(+) T cell responses, which could be used to potentiate a human universal T-epitope vaccine against leishmaniasis.Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPQ)Fundacao Carlos Chagas de Amparo a Pesquisa do Estado de Rio de Janeiro (FAPERJ)Coordenacao de Aperfeicoamento de Pessoal de Nivel SuperiorCNPQ-Fundacao de Apoio a Pesquisa e a Inovacao Tecnologica do Estado de Sergipe-PRONEXFAPITEC CNPq (PRONEX)VII PN I+D+IFEDER FundsUniv Fed Sergipe HU UFS, Dept Med, Univ Hosp, Mol Biol Lab, Aracaju, Sergipe, BrazilUniv Fed Rio de Janeiro, Inst Microbiol Paulo de Goes, Dept Microbiol Geral, Lab Biol Bioquim Leishmania, Rio De Janeiro, RJ, BrazilPontificia Univ Catolica Rio de Janeiro, Lab Biometrol, Programa Posgrad Metrol, Rio De Janeiro, RJ, BrazilInst Salud Carlos III, WHO Collaborating Ctr Leishmaniasis, Ctr Nacl Microbiol, Madrid, Comunidad De Ma, SpainInst Oswaldo Cruz, Lab Imunoparasitol, Rio De Janeiro, RJ, BrazilUniv Fed Rio de Janeiro, Inst Microbiologia Paulo de Goes, Dept Imunol, Lab Imunol Integrada, Rio De Janeiro, RJ, BrazilUniv Sao Paulo, Fac Med, Inst Invest Imunol, Sao Paulo, BrazilUniv Fed Sao Paulo UNIFESP, Dept Microbiol Imunol & Parasitol, Lab Vacinas Expt, Sao Paulo, SP, BrazilUniv Fed Rio de Janeiro, Fac Med, Lab Imunohematol, Hosp Univ Clementino Fraga Filho, Rio De Janeiro, RJ, BrazilUniv Fed Sergipe HU UFS, Dept Morfol, Aracaju, Sergipe, BrazilUniv Fed Sao Paulo UNIFESP, Dept Microbiol Imunol & Parasitol, Lab Vacinas Expt, Sao Paulo, SP, BrazilCNPq: 300639/2003-1CNPq: 310977/2014-2CNPq: 310797/2015-2CNPq: 404400/2012-4FAPERJ: E-26-201.583/2014FAPERJ: E-26-102957/2011FAPERJ: E-26/111.682/2013FAPERJ: E-26/102415/2010FAPERJ: E-26/201747/2015CAPES: 23038.005304/2011-0CNPQ-PRONEX: 12/2009FAPITEC CNPq (PRONEX): 019.203.02712/2009-8FEDER Funds: RICET RD12/0018/0003Web of Scienc

Translational research into gut microbiota: new horizons on obesity treatment: updated 2014

Obesity is currently a pandemic of worldwide proportions affecting millions of people. Recent studies have proposed the hypothesis that mechanisms not directly related to the human genome could be involved in the genesis of obesity, due to the fact that, when a population undergoes the same nutritional stress, not all individuals present weight gain related to the diet or become hyperglycemic. The human intestine is colonized by millions of bacteria which form the intestinal flora, known as gut flora. Studies show that lean and overweight human may present a difference in the composition of their intestinal flora; these studies suggest that the intestinal flora could be involved in the development of obesity. Several mechanisms explain the correlation between intestinal flora and obesity. The intestinal flora would increase the energetic extraction of non-digestible polysaccharides. In addition, the lipopolysaccharide from intestinal flora bacteria could trigger a chronic sub-clinical inflammatory process, leading to obesity and diabetes. Another mechanism through which the intestinal flora could lead to obesity would be through the regulation of genes of the host involved in energy storage and expenditure. In the past five years data coming from different sources established causal effects between intestinal microbiota and obesity/insulin resistance, and it is clear that this area will open new avenues of therapeutic to obesity, insulin resistance and DM2

The Characterisation of Three Types of Genes that Overlie Copy Number Variable Regions

Background: Due to the increased accuracy of Copy Number Variable region (CNV) break point mapping, it is now possible to say with a reasonable degree of confidence whether a gene (i) falls entirely within a CNV; (ii) overlaps the CNV or (iii) actually contains the CNV. We classify these as type I, II and III CNV genes respectively. Principal Findings: Here we show that although type I genes vary in copy number along with the CNV, most of these type I genes have the same expression levels as wild type copy numbers of the gene. These genes must, therefore, be under homeostatic dosage compensation control. Looking into possible mechanisms for the regulation of gene expression we found that type I genes have a significant paucity of genes regulated by miRNAs and are not significantly enriched for monoallelically expressed genes. Type III genes, on the other hand, have a significant excess of genes regulated by miRNAs and are enriched for genes that are monoallelically expressed. Significance: Many diseases and genomic disorders are associated with CNVs so a better understanding of the different ways genes are associated with normal CNVs will help focus on candidate genes in genome wide association studies