46 research outputs found

    Atividade in vitro de extratos de Artemisia annua L (Asteraceae) sobre Rhipicephalus (Boophilus) microplus

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    The activity of plant extracts on parasites may indicate groups of substances that are potentially useful for controlling Rhipicephalus (Boophilus) microplus. The aim of the present study was to investigate the in vitro action of Artemisia annua extracts on this tick. The concentrations of the sesquiterpene lactones artemisinin and deoxyartemisinin present in plant extracts were quantified via high-performance liquid chromatography. Four extracts produced from the concentrated crude extract (CCE) were evaluated on larvae using the impregnated paper method, with readings after 24 hours of incubation. The engorged females were immersed in the CCE and in its four derived extracts for five minutes, with incubation for subsequent analysis of biological parameters. The extracts were not effective on the larvae at the concentrations tested (3.1 to 50 mg.mL-1). The CCE showed greater efficacy on engorged females (EC50 of 130.6 mg.mL-1 and EC90 of 302.9 mg.mL-1) than did the derived extracts. These results tend to confirm that the action of artemisinin on engorged females of R.(B.) microplus is conditional to their blood intake. In this case, in vitro methods would be inadequate for effective evaluation of the action of A. annua on R. (B.) microplus.A atividade de extratos vegetais sobre parasitas pode indicar grupos de substâncias de uso potencial no controle de Rhipicephalus (Boophilus) microplus. O objetivo do presente estudo foi investigar a ação in vitro de extratos de Artemisia annua sobre esta espécie. A concentração das lactonas sesquiterpênicas artemisinina e deoxiartemisinina presentes nos extratos vegetais, foi quantificada via cromatografia líquida de alta eficiência. Quatro extratos produzidos a partir do extrato bruto concentrado (EBC) foram avaliados sobre larvas pela metodologia do papel impregnado, com leitura após 24 horas de incubação. As fêmeas ingurgitadas foram imersas por cinco minutos no EBC e nos seus quatro extratos derivados, e incubadas para posterior análise dos parâmetros biológicos. Os extratos não tiveram eficácia sobre as larvas nas concentrações avaliadas (de 3,1 a 50 mg.mL-1). O EBC apresentou melhor eficácia sobre as fêmeas ingurgitadas (CE 50 de 130,6 mg.mL-1 e CE 90 de 302,9 mg.mL-1) que os extratos derivados. Esses resultados tendem a confirmar que a ação da artemisinina sobre as fêmeas ingurgitadas de R. (B.) microplus estaria condicionada à sua ingestão através do sangue. Nesse caso, os métodos in vitro seriam inadequados para a efetiva avaliação da ação de A. annua R.(B.) microplus.313

    Expression of inducible nitric oxide synthase in macrophages inversely correlates with parasitism of lymphoid tissues in dogs with visceral leishmaniasis

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    Abstract\ud \ud Background\ud There are only a few studies reporting the role of nitric oxide metabolites for controlling macrophage intracellular parasitism, and these are controversial. Therefore, the present study aimed to evaluate the expression of inducible nitric oxide synthase (iNOS) in the lymph nodes and spleen of dogs affected by visceral leishmaniasis through immunohistochemistry and to determine its correlation with tissue parasite burden and serum interferon (IFN)-γ levels. Twenty-eight dogs were selected and assigned to one of two groups, symptomatic (n = 18) and asymptomatic (n = 10), according to clinical status and laboratory evaluation. A negative control group (n = 6) from a non-endemic region for visceral leishmaniasis was included as well.\ud \ud \ud Results\ud Parasite density (amastigotes/mm2) was similar between clinical groups in the lymph nodes (P = 0.2401) and spleen (P = 0.8869). The density of iNOS+ cells was higher in infected dogs compared to controls (P < 0.05), without a significant difference in lymph node (P = 0.3257) and spleen (P = 0.5940) densities between symptomatic and asymptomatic dogs. A positive correlation was found between the number of iNOS+ cells in lymph nodes and interferon-γ levels (r = 0.3776; P = 0.0303), and there was a negative correlation between parasites and iNOS+ cell densities both in lymph nodes (r = −0.5341; P = 0.0034) and spleen (r = −0.4669; P = 0.0329).\ud \ud \ud Conclusion\ud The negative correlation observed between tissue parasitism and the expression of iNOS may be a reflection of NO acting on the control of parasites.CNP

    Metabolic effect of low fluoride levels in the islets of NOD mice: integrative morphological, immunohistochemical, and proteomic analyses

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    Fluoride (F) has been widely used to control dental caries, and studies suggest beneficial effects against diabetes when a low dose of F is added to the drinking water (10 mgF/L). Objectives: This study evaluated metabolic changes in pancreatic islets of NOD mice exposed to low doses of F and the main pathways altered by the treatment. Methodology: In total, 42 female NOD mice were randomly divided into two groups, considering the concentration of F administered in the drinking water for 14 weeks: 0 or 10 mgF/L. After the experimental period, the pancreas was collected for morphological and immunohistochemical analysis, and the islets for proteomic analysis. Results: In the morphological and immunohistochemical analysis, no significant differences were found in the percentage of cells labelled for insulin, glucagon, and acetylated histone H3, although the treated group had higher percentages than the control group. Moreover, no significant differences were found for the mean percentages of pancreatic areas occupied by islets and for the pancreatic inflammatory infiltrate between the control and treated groups. Proteomic analysis showed large increases in histones H3 and, to a lesser extent, in histone acetyltransferases, concomitant with a decrease in enzymes involved in the formation of acetyl-CoA, besides many changes in proteins involved in several metabolic pathways, especially energy metabolism. The conjunction analysis of these data showed an attempt by the organism to maintain protein synthesis in the islets, even with the dramatic changes in energy metabolism. Conclusion: Our data suggests epigenetic alterations in the islets of NOD mice exposed to F levels comparable to those found in public supply water consumed by humans

    The inventory of geological heritage of the state of São Paulo, Brazil: Methodological basis, results and perspectives

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    An inventory of geological sites based on solid and clear criteria is a first step for any geoconservation strategy. This paper describes the method used in the geoheritage inventory of the State of São Paulo, Brazil, and presents its main results. This inventory developed by the geoscientific community aimed to identify geosites with scientific value in the whole state, using a systematic approach. All 142 geosites representative of 11 geological frameworks were characterised and quantitatively evaluated according to their scientific value and risk of degradation, in order to establish priorities for their future management. An online database of the inventory is under construction, which will be available to be easily consulted and updated by the geoscientific community. All data were made available to the State Geological Institute as the backbone for the implementation of a future state geoconservation strategy.The authors acknowledge the Science Without Borders Programme, Process 075/2012, which supported this study and the São Paulo Research Foundation (FAPESP), Process 2011/17261-6. We also thanks C. Mazoca for his help with maps and figures.info:eu-repo/semantics/acceptedVersio

    Canagliflozin and renal outcomes in type 2 diabetes and nephropathy

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    BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to &lt;90 ml per minute per 1.73 m2 of body-surface area and albuminuria (ratio of albumin [mg] to creatinine [g], &gt;300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of &lt;15 ml per minute per 1.73 m2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P&lt;0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P&lt;0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years

    Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

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    Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection
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