1,744 research outputs found
Lack of tolerance for the anti-dyskinetic effects of 7-nitroindazole, a neuronal nitric oxide synthase inhibitor, in rats
7-Nitroindazole (7-NI) inhibits neuronal nitric oxide synthase in vivo and reduces l-DOPA-induced dyskinesias in a rat model of parkinsonism. The aim of the present study was to determine if the anti-dyskinetic effect of 7-NI was subject to tolerance after repeated treatment and if this drug could interfere with the priming effect of l-DOPA. Adult male Wistar rats (200-250 g) with unilateral depletion of dopamine in the substantia nigra compacta were treated with l-DOPA (30 mg/kg) for 34 days. On the 1st day, 6 rats received ip saline and 6 received ip 7-NI (30 mg/kg) before l-DOPA. From the 2nd to the 26th day, all rats received l-DOPA daily and, from the 27th to the 34th day, they also received 7-NI before l-DOPA. Animals were evaluated before the drug and 1 h after l-DOPA using an abnormal involuntary movement scale and a stepping test. All rats had a similar initial motor deficit. 7-NI decreased abnormal involuntary movement induced by l-DOPA and the effect was maintained during the experiment before 7-NI, median (interquartile interval), day 26: 16.75 (15.88-17.00); day 28: 0.00 (0.00-9.63); day 29: 13.75 (2.25-15.50); day 30: 0.5 (0.00-6.25); day 31: 4.00 (0.00-7.13), and day 34: 0.5 (0.00-14.63), Friedman followed by Wilcoxon test,vs day 26, P < 0.05;. The response to l-DOPA alone was not modified by the use of 7-NI before the first administration of the drug (l-DOPA vs time interaction, F1,10 = 1.5, NS). The data suggest that tolerance to the anti-dyskinetic effects of a neuronal nitric oxide synthase inhibitor does not develop over a short-term period of repeated administration. These observations open a possible new therapeutic approach to motor complications of chronic l-DOPA therapy in patients with Parkinson’s disease
Photoacoustic Monitoring Of Magnetite-crystal Formation From Iron(iii) Hydroxide Acetate: Comparison With Esr Results
The formation of crystalline magnetite by 1-h heat treatment of iron(III) hydroxide acetate is described. This amorphous-crystalline solid transformation is monitored by electron-spin resonance and photoacoustic spectroscopies. No significant changes were detected for samples heated below 190 °C. Above this temperature both techniques presented results following a definite pattern, namely, the enhancement of ion mobility leading to particle growth and crystallization for a temperature up to 240 °C and the onset of magnetic ordering of magnetite near this temperature.65125150515
Analysis of access to hypertensive and diabetic drugs in the Family Health Strategy, State of Pernambuco, Brazil
OBJECTIVE: To evaluate the access to drugs for hypertension and diabetes and the direct cost of buying them among users of the Family Health Strategy (FHS) in the state of Pernambuco, Brazil. METHODS: Population-based, cross-sectional study of a systematic random sample of 785 patients with hypertension and 823 patients with diabetes mellitus who were registered in 208 randomly selected FHS teams in 35 municipalities of the state of Pernambuco. The selected municipalities were classified into three levels with probability proportional to municipality size (LS, large-sized; MS, medium-sized; SS, small-sized). To verify differences between the cities, we used the χ2 test. RESULTS: Pharmacological treatment was used by 91.2% patients with hypertension whereas 85.6% patients with diabetes mellitus used oral antidiabetic drugs (OADs), and 15.4% used insulin. The FHS team itself provided antihypertensive medications to 69.0% patients with hypertension, OADs to 75.0% patients with diabetes mellitus, and insulin treatment to 65.4%. The 36.9% patients with hypertension and 29.8% with diabetes mellitus that had to buy all or part of their medications reported median monthly cost of R 14.00, and R$ 27.61 for antihypertensive drugs, OADs, and insulin, respectively
Presubiculum stimulation in vivo evokes distinct oscillations in superficial and deep entorhinal cortex layers in chronic epileptic rats
The characteristic cell loss in layer III of the medial entorhinal area (MEA-III) in human mesial temporal lobe epilepsy is reproduced in the rat kainate model of the disease. To understand how this cell loss affects the functional properties of the MEA, we investigated whether projections from the presubiculum (prS), providing a main input to the MEA-III, are altered in this epileptic rat model. Injections of an anterograde tracer in the prS revealed bilateral projection fibers mainly to the MEA-III in both control and chronic epileptic rats. We further examined the prS-MEA circuitry using a 16-channel electrode probe covering the MEA in anesthetized control and chronic epileptic rats. With a second 16-channel probe, we recorded signals in the hippocampus. Current source density analysis indicated that, after prS double-pulse stimulation, afterdischarges in the form of oscillations (20-45 Hz) occurred that were confined to the superficial layers of the MEA in all epileptic rats displaying MEA-III neuronal loss. Slower oscillations (theta range) were occasionally observed in the deep MEA layers and the dentate gyrus. This kind of oscillation was never observed in control rats. We conclude that dynamical changes occur in an extensive network within the temporal lobe in epileptic rats, manifested as different kinds of oscillations, the characteristics of which depend on local properties of particular subareas. These findings emphasize the significance of the entorhinal cortex in temporal lobe epilepsy and suggest that the superficial cell layers could play an important role in distributing oscillatory activity.status: publishe
Genetic analysis of members of the species Oropouche virus and identification of a novel M segment sequence
Oropouche virus (OROV) is a public health threat in South America, and in particular Northern Brazil, causing frequent outbreaks of febrile illness. Using a combination of deep sequencing and Sanger sequencing approaches we have determined complete genome sequences of eight clinical isolates that were obtained from patient sera during an Oropouche fever outbreak in Amapa state, northern Brazil in 2009. We also report complete genome sequences of two OROV reassortants isolated from two marmosets in Minas Gerais state, southeast Brazil in 2012 that contain a novel M genome segment. Interestingly, all ten isolates posses a 947 nucleotide long S segment that lacks 11 residues in the S segment 3' UTR compared to the recently redetermined Brazilian prototype OROV strain BeAn19991. OROV maybe circulating more widely in Brazil and in the non-human primate population than previously appreciated and the identification of yet another reassortant highlights the importance of bunyavirus surveillance in South America
The DNA damage response is developmentally regulated in the African trypanosome
Genomes are affected by a wide range of damage, which has resulted in the evolution of a number of widely conserved DNA repair pathways. Most of these repair reactions have been described in the African trypanosome Trypanosoma brucei, which is a genetically tractable eukaryotic microbe and important human and animal parasite, but little work has considered how the DNA damage response operates throughout the T. brucei life cycle. Using quantitative PCR we have assessed damage induction and repair in both the nuclear and mitochondrial genomes of the parasite. We show differing kinetics of repair for three forms of DNA damage, and dramatic differences in repair between replicative life cycle forms found in the testse fly midgut and the mammal. We find that mammal-infective T. brucei cells repair oxidative and crosslink-induced DNA damage more efficiently than tsetse-infective cells and, moreover, very distinct patterns of induction and repair of DNA alkylating damage in the two life cycle forms. We also reveal robust repair of DNA lesions in the highly unusual T. brucei mitochondrial genome (the kinetoplast). By examining mutants we show that nuclear alkylation damage is repaired by the concerted action of two repair pathways, and that Rad51 acts in kinetoplast repair. Finally, we correlate repair with cell cycle arrest and cell growth, revealing that induced DNA damage has strikingly differing effects on the two life cycle stages, with distinct timing of alkylation-induced cell cycle arrest and higher levels of damage induced death in mammal-infective cells. Our data reveal that T. brucei regulates the DNA damage response during its life cycle, a capacity that may be shared by many microbial pathogens that exist in variant environments during growth and transmission
Relato de Pesquisa: Projeto Ciência e Performance, estudo da Conferência Internacional sobre Comunicação Pública da Ciência e Tecnologia
O presente artigo está relacionado ao Projeto de Pesquisa “Ciência e Performance: estudo da Conferência Internacional sobre Comunicação Pública da Ciência e Tecnologia”. Apresentamos aqui os resultados parciais de um questionário disponibilizado no dia 13 de maio de 2014, logo após a Conferência na Bahia-Brasil, numa lista de discussão da Network for the Public Communication of Science and Technology (PCST). O questionário obteve 42 respostas de pesquisadores de diferentes países, com predominância do Brasil, Índia, Estados Unidos e Itália, seguidos da Austrália e da Inglaterra. INFORME DE INVESTI GACION : PROYE CTO DE INVESTI GACIÓN “CIEN CIA Y PERFOR MAN CE: ESTU DIO DE LA CONFEREN CIA INTERNA CIO NAL SOBRE COMUNI CACIÓN PÚBLI CA DE LA CIEN CIA Y LA TE CNO LO GÍA ”Resumen: El presente artículo está relacionado con el Proyecto de Investigación “Ciencia y Performance: estudio de la Conferencia Internacional sobre Comunicación Pública de la Ciencia y la Tecnología”. Presentamos aquí los resultados parciales de una encuesta realizada en el día 13 de mayo de 2014, poco después de la Conferencia en Bahía-Brasil, en una lista de discusión de la Network for the Public Communication of Science and Technology (PCST). El cuestionario obtuvo 42 respuestas de investigadores de diferentes países, con predominio de Brasil, India, Estados Unidos e Italia, seguidos de Australia e InglaterraRESEARCH RE PORT : RESEAR CH PRO JECT “SCIEN CE AN D PERFOR MAN CE: STU DY OF INTERNATIONAL INTERNATIONAL PUBLI C COMMUNI CATION ATION OF SCIEN CE AN D TE CHNOLO GY CONFEREN CE”ABSTRACT: The present work is a report Concerning the Research Project “Science and Performance: Study of International Public Communication of Science and Technology Conference”. We present here the partial results of a questionnaire made available on May 13, 2014, shortly after the Conference in Bahia, Brazil, in a mailing list of the Network for the Public Communication of Science and Technology. The survey received 42 responses from researchers of different countries, especially Brazil, India, United States and Italy, followed by Australia and England
An Improved Description of the Dielectric Breakdown in Oxides Based on a Generalized Weibull distribution
In this work, we address modal parameter fluctuations in statistical
distributions describing charge-to-breakdown and/or
time-to-breakdown during the dielectric breakdown regime of
ultra-thin oxides, which are of high interest for the advancement of electronic
technology. We reobtain a generalized Weibull distribution (-Weibull), which
properly describes data when oxide thickness fluctuations are
present, in order to improve reliability assessment of ultra-thin oxides by
time-to-breakdown extrapolation and area scaling. The incorporation
of fluctuations allows a physical interpretation of the -Weibull
distribution in connection with the Tsallis statistics. In support to our
results, we analyze data of SiO-based MOS devices obtained
experimentally and theoretically through a percolation model, demonstrating an
advantageous description of the dielectric breakdown by the -Weibull
distribution.Comment: 5 pages, 3 figure
Marine mammal bycatch by the industrial bottom trawl fishery at the Río de la Plata Estuary and the adjacent Atlantic Ocean
Fisheries interactions with non-target marine vertebrates are a worldwide problem. The impact of coastal bottom trawl fisheries on marine mammals has never been evaluated before in the Río de la Plata Estuary and the adjacent Atlantic Ocean. Our aim was estimating the bycatch per unit effort (BcPUE) and incidental mortality rates of marine mammals caused by the industrial coastal bottom trawl fisheries fleet. We evaluated the mortality of three species (i.e., franciscana dolphin Pontoporia blainvillei, South American sea lion Otaria flavescens, and the South American fur seal Arctocephalus australis); these species are facing conservation problems either at the regional or local scale. We conducted an onboard data collection program of marine mammals' bycatch involving crew members of 10 vessels (30%) of the Uruguayan coastal bottom trawl fleet between January 2009 and April 2012. A total of 102 marine mammal individuals were bycaught during 490 fishing trips involving 2,398 fishing days. Mortalities estimated for franciscana dolphin were the highest among the species affected, with values adding up to ~100 individuals for year (with scenarios of population decline in the area), followed by South American sea lion with ~77 individuals by year (0.8% of local population) and the South American fur seal with an annual mortality estimate of ~25 individuals (~0.02% of local population). BcPUE showed significant temporal variation, with franciscana dolphin BcPUE varying seasonally and those of otariids according to their breeding season. Our estimates of marine mammal bycatch by bottom trawl fisheries should constitute an important input for the sustainable management of fisheries and the conservation of marine biodiversity in the southwestern Atlantic Ocean.Fil: Franco Trecu, Valentina. Universidad de la República; UruguayFil: Szephegyi, María Nube. Universidad de la Republica; UruguayFil: Doño, Florencia. Universidad de la Republica; UruguayFil: Forselledo, Rodrigo. Universidad de la Republica; UruguayFil: Reyes, Federico. Universidad de la Republica; UruguayFil: Passadore, Cecilia. Universidad de la Republica; Uruguay. Flinders University; AustraliaFil: Crespo, Enrique Alberto. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Inchausti, Pablo. Universidad de la República; Urugua
Economic Impact of a Rotavirus Vaccine in Brazil
The study was done to evaluate the cost-effectiveness of a national
rotavirus vaccination programme in Brazilian children from the
healthcare system perspective. A hypothetical annual birth-cohort was
followed for a five-year period. Published and national administrative
data were incorporated into a model to quantify the consequences of
vaccination versus no vaccination. Main outcome measures included the
reduction in disease burden, lives saved, and disability-adjusted
life-years (DALYs) averted. A rotavirus vaccinationprogramme in Brazil
would prevent an estimated 1,804 deaths associated with gastroenteritis
due to rotavirus, 91,127 hospitalizations, and 550,198 outpatient
visits. Vaccination is likely to reduce 76% of the overall healthcare
burden of rotavirus-associated gastroenteritis in Brazil. At a vaccine
price of US
643 per DALY averted. Rotavirus vaccination can reduce the burden of
gastroenteritis due to rotavirus at a reasonable cost-effectiveness
ratio
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