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1.
J Hosp Infect ; 117: 96-102, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34461175

RESUMO

BACKGROUND: Studies show that healthcare-associated infections (HAIs) represent a crucial issue in healthcare and can lead to substantial economic impacts in intensive care units (ICUs). AIM: To estimate direct costs associated with the most significant HAIs in 50 teaching hospitals in Brazil, affiliated to the unified health system (Sistema Único de Saúde: SUS). METHODS: A Monte Carlo simulation model was designed to estimate the direct costs of HAIs; first, epidemiologic and economic parameters were established for each HAI based on a cohort of 949 critical patients (800 without HAI and 149 with); second, simulation based on three Brazilian prevalence scenarios of HAIs in ICU patients (29.1%, 51.2%, and 61.6%) was used; and third, the annual direct costs of HAIs in 50 university hospitals were simulated. FINDINGS: Patients with HAIs had 16 additional days in the ICU, along with an extra direct cost of US$13.892, compared to those without HAIs. In one hypothetical scenario without HAI, the direct annual cost of hospital care for 26,649 inpatients in adult ICUs of 50 hospitals was US$112,924,421. There was an increase of approximately US$56 million in a scenario with 29.1%, and an increase of US$147 million in a scenario with 61.6%. The impact on the direct cost became significant starting at a 10% prevalence of HAIs, where US$2,824,817 is added for each 1% increase in prevalence. CONCLUSION: This analysis provides robust and updated estimates showing that HAI places a significant financial burden on the Brazilian healthcare system and contributes to a longer stay for inpatients.


Assuntos
Infecção Hospitalar , Adulto , Brasil/epidemiologia , Infecção Hospitalar/epidemiologia , Atenção à Saúde , Hospitais Universitários , Humanos , Unidades de Terapia Intensiva , Tempo de Internação
2.
Parasit Vectors ; 14(1): 339, 2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34174956

RESUMO

BACKGROUND: There is a paucity of recent data and knowledge on mosquito diversity and potential vectors of arboviruses in South Africa, with most of the available data dating back to the 1950s-1970s. Aedes and Culex species are the major vectors of some of the principal arboviruses which have emerged and re-emerged in the past few decades. METHODS: In this study we used entomological surveillance in selected areas in the north-eastern parts of South Africa from 2014 to 2018 to assess mosquito diversity, with special emphasis on the Aedes species. The impact of trap types and environmental conditions was also investigated. Identification of the blood meal sources of engorged females collected during the study period was carried out, and DNA barcodes were generated for selected species. RESULTS: Overall, 18.5% of the total Culicidae mosquitoes collected belonged to the genus Aedes, with 14 species recognised or suspected vectors of arboviruses. Species belonging to the Neomelaniconion subgenus were commonly collected in the Bushveld savanna at conservation areas, especially Aedes mcintoshi and Aedes circumluteolus. Aedes aegypti was present in all sites, albeit in low numbers. Temperature was a limiting factor for the Aedes population, and they were almost exclusively collected at temperatures between 18 °C and 27 °C. The cytochrome oxidase subunit I (COI) barcode fragment was amplified for 21 Aedes species, and for nine of these species it was the first sequence information uploaded on GenBank. CONCLUSION: This study provides a better understanding of the diversity and relative abundance of Aedes species in the north-east of South Africa. The information provided here will contribute to future arboviral research and implementation of efficient vector control and prevention strategies.


Assuntos
Aedes/fisiologia , Comportamento Alimentar , Aedes/classificação , Aedes/genética , Animais , Ecossistema , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Proteínas de Insetos/genética , Mosquitos Vetores/classificação , Mosquitos Vetores/genética , Mosquitos Vetores/fisiologia , África do Sul , Temperatura
3.
Environ Pollut ; 284: 117209, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33932832

RESUMO

Contaminant levels are lower in Antarctica than elsewhere in the world because of its low anthropogenic activities. However, the northern region of the Antarctic Peninsula, is close to South America and experiences the greatest anthropogenic pressure in Antarctica. Here, we investigated, in two Antarctic Peninsula islands, intra and interspecific factors that influence the concentrations of 17 trace elements (TEs) in blood and feathers of three penguin species breeding sympatrically in relation to their trophic ecology assessed via a stable isotopic approach (C, N and S). Geographical location, foraging zone (δ13C and δ34S) and diet influences the interspecific difference, and sex and maturity stage diet influence the intraspecific difference of Pygoscelis penguins. Penguins from Livingston showed higher values (mean, ng. g-1, dry weight - dw) of Zn (103), Mn (0.3), and Fe (95) than those from King George Island (Zn: 80, Mn: 1.9, and Fe: 11). Gender-related differences were observed, as males showed significantly higher values (mean, ng. g-1, dw) of Rb (3.4) and δ15N in blood of gentoo, and Ca (1344) in Adélie feathers. Chicks of gentoo and Adélie presented higher Zn, Mg, Ca, and Sr and lower 13C values in blood than adults. The highest concentrations (mean, ng. g-1, dw) of Cd (0.2) and Cu (26), and the lowest δ15N values were found in chinstrap. Geographical, intraspecific (i.e., ontogenetic and gender-related) and interspecific differences in feeding seemed to have influenced TE and stable isotope values in these animals. The TE bioaccumulation by penguins may have also been influenced by natural enrichment in environmental levels of these elements, which seems to be the case for Fe, Zn, and Mn. However, the high level of some of the TEs (Mn, Cd, and Cr) may reflect the increase of local and global human activities.


Assuntos
Spheniscidae , Oligoelementos , Animais , Regiões Antárticas , Plumas/química , Humanos , Ilhas , Masculino , América do Sul , Oligoelementos/análise
4.
Arq. bras. med. vet. zootec. (Online) ; 73(1): 265-269, Jan.-Feb. 2021. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1153035

RESUMO

Dois carrapatos adultos, sendo um Amblyomma nodosum e um Amblyomma humerale foram encontrados parasitando ativamente uma capivara (Hydrochoerus hydrochaeris) proveniente da região central do estado de Rondônia, Brasil, na zona rural do município de Ji-Paraná, localizado na Amazônia ocidental. Poucos trabalhos científicos relatam a presença de A. humerale em capivaras. Assim, esta é a primeira vez que A. nodosum é relatado parasitando essa espécie animal. Por não se tratar de um hospedeiro animal conhecido para A. nodosum ou comum para A. humerale, esses achados podem sugerir uma nova relação entre hospedeiros para eles. Portanto, são necessários mais estudos acerca da ecologia desses parasitas, principalmente por serem potenciais transmissores de patógenos de importância em medicina veterinária e saúde pública.(AU)


Assuntos
Animais , Roedores/parasitologia , Ixodidae , Amblyomma , Brasil , Ecossistema Amazônico , Ácaros e Carrapatos
5.
J Hosp Infect ; 106(2): 303-310, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32693085

RESUMO

BACKGROUND: Little is known about the economic burden of healthcare-associated infections (HAIs) in Brazil. AIM: To analyse the costs of hospitalization by reimbursement from the Brazilian government, via the Brazilian Unified Health System (SUS) affiliation, and direct costs in the adult Intensive Care Unit (ICU). METHODS: The matched-pairs case-control study (83 patients with HAIs and 83 without HAIs) was performed at a referral tertiary-care teaching hospital in Brazil in January 2018. In order to calculate the HAI costs from the perspective of the payer, the total cost for each hospitalization was obtained through the Hospital's Billing Sector. Direct costs were calculated annually for 949 critical patients during 2018. FINDINGS: The reimbursement cost per hospitalization of patients with HAIs was 75% (US$2721) higher than patients without HAIs (US$1553). When a patient has an HAI, in addition to a longer length of stay (15 days), there was an extra increase (US$996) in the reimbursement cost per hospitalization. An HAI in the ICU was associated with a total direct cost eight times higher compared with patients who did not develop infections in this unit, US$11,776 × US$1329, respectively. The direct cost of hospitalization in the ICU without HAI was 56.5% less than the reimbursement (US$1329 × US$3052, respectively), whereas for the patient with an HAI, the direct cost was 111.5% above the reimbursement (US$11,776 × US$5569, respectively). CONCLUSION: HAIs contribute to a longer stay and an eight-fold increase in direct costs. It is necessary to reinforce programmes that prevent HAIs in Brazilian hospitals.


Assuntos
Infecção Hospitalar/economia , Atenção à Saúde/economia , Custos Hospitalares/estatística & dados numéricos , Centros de Atenção Terciária/estatística & dados numéricos , Adulto , Brasil/epidemiologia , Estudos de Casos e Controles , Criança , Infecção Hospitalar/epidemiologia , Atenção à Saúde/estatística & dados numéricos , Hospitais de Ensino/estatística & dados numéricos , Humanos , Recém-Nascido , Unidades de Terapia Intensiva/economia , Tempo de Internação/economia
6.
Crit Rev Food Sci Nutr ; 59(7): 1115-1123, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29040025

RESUMO

Pistachio is a nut with high polyunsaturated fatty acids (PUFA), monounsaturated fatty acids (MUFA), polyphenols and carotenoids content, and the synergism between these compounds appears to affect glucose metabolism. In this systematic review we analyzed studies in which the effect of chronic consumption of pistachio on markers of glucose metabolism was evaluated in pre-diabetic and type 2 diabetics. We used the PubMed, Scopus, Cochrane and Lilacs databases. The research terms used were pistachio, pre-diabetes, type 2 diabetes mellitus, insulin resistance, blood glucose, hyperglycemia and glycated hemoglobin (HbA1c). Four articles were selected, of which three tested the intake of 50 to 57 g of pistachio/day and one 20% of the daily caloric intake, for a period of 1 to 4 months. Studies reported a decrease in fasting blood glucose, insulinemia, HOMA-IR, and fructosamine, but no change in HbA1c. Lower concentrations of miR-192 and miR-375 were also found, which correlated positively with HOMA-IR. The synergism between PUFA, MUFA, polyphenols and carotenoids present in pistachios can modulate specific miRNA, increasing insulin sensitivity through the PI3K-AKT signaling pathway. This modulation can be used as a tool to monitor the response to interventions, favoring the prevention and treatment of complications related to diabetes.


Assuntos
Diabetes Mellitus Tipo 2/dietoterapia , Carboidratos da Dieta , Glucose/metabolismo , Pistacia/química , Glicemia/metabolismo , Carotenoides/farmacologia , Bases de Dados Factuais , Diabetes Mellitus/dietoterapia , Jejum , Ácidos Graxos Monoinsaturados/farmacologia , Ácidos Graxos Insaturados/farmacologia , Frutose/sangue , Hemoglobinas Glicadas , Humanos , Hiperglicemia/dietoterapia , Insulina/sangue , Resistência à Insulina , MicroRNAs , Fosfatidilinositol 3-Quinases , Polifenóis/farmacologia
7.
Med Vet Entomol ; 30(3): 301-9, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27279553

RESUMO

Wolbachia pipientis (Rickettsiales: Rickettsiaceae) protects mosquitoes from infections with arboviruses and parasites. However, the effect of its co-infection on vector competence for Dirofilaria immitis (Spirurida: Onchocercidae) in the wild has not been investigated. This study aimed to screen vectors of D. immitis for wPip, to characterize these, and to investigate a possible association between the occurrence of W. pipientis and that of the nematode. The presence of W. pipientis was assessed in the five mosquito potential vectors of D. immitis in Portugal. Polymerase chain reaction (PCR) products were sequenced, and wPip haplotypes were determined by PCR-restricted fragment length polymorphism (RFLP). Results showed that wPip was detected in 61.5% of Culex pipiens (Diptera: Culicidae) pools and 6.3% of Culex theileri pools. wPip 16s rRNA sequences found in Cx. theileri exactly match those from Cx. pipiens, confirming a mosquito origin, rather than a nematode origin, as some specimens were infected with D. immitis. Only wPip haplotype I was found. No association was found between the presence of wPip and D. immitis in mosquitoes and hence a role for this endosymbiont in influencing vectorial competence is yet to be identified. This study contributes to understanding of wPip distribution in mosquito populations and, to the best of the authors' knowledge, is the first report of natural infections by wPip in Cx. theileri.


Assuntos
Culex/microbiologia , DNA Bacteriano/genética , Mosquitos Vetores/microbiologia , RNA Ribossômico 16S/genética , Wolbachia/isolamento & purificação , Animais , Culex/parasitologia , Dirofilaria immitis/isolamento & purificação , Dirofilariose/parasitologia , Dirofilariose/transmissão , Haplótipos , Mosquitos Vetores/parasitologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Portugal , Wolbachia/genética
8.
Phys Med ; 32(6): 812-7, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27184550

RESUMO

Microtomography using synchrotron sources is a useful tool in biological imaging research since the phase coherence of synchrotron beams can be exploited to obtain images with high contrast resolution. This work is part of a series of works using phase contrast synchrotron microtomography in the study of Rhodnius prolixus head, the insect vector of Chagas' disease, responsible for about 12,000 deaths per year. The control of insect vector is the most efficient method to prevent this disease and studies have shown that the use of triflumuron, a chitin synthesis inhibitor, disrupted chitin synthesis during larval development and it's an alternative method against insect pests. The aim of this work was to investigate the biological effects of treatments with triflumuron in the ecdysis period (the moulting of the R. prolixus cuticle) using the new imaging beamline IMX at LNLS (Brazilian Synchrotron Light Laboratory). Nymphs of R. prolixus were taken from the Laboratory of Biochemistry and Physiology of Insects, Oswaldo Cruz Foundation, Brazil. Doses of 0.05mg of triflumuron were applied directly to the abdomen on half of the insects immediately after feeding. The insects were sacrificed 25days after feeding (intermoulting period) and fixed with glutaraldehyde. The results obtained using phase contrast synchrotron microtomography in R. prolixus showed amazing images of the effects of triflumuron on insects in the ecdysis period, and the formation of the new cuticle on those which were not treated with triflumuron. Both formation and malformation of this insect's cuticle have never been seen before with this technique.


Assuntos
Cabeça/diagnóstico por imagem , Cabeça/crescimento & desenvolvimento , Muda , Rhodnius/anatomia & histologia , Rhodnius/crescimento & desenvolvimento , Síncrotrons , Microtomografia por Raio-X/métodos , Animais , Benzamidas/farmacologia , Muda/efeitos dos fármacos , Microtomografia por Raio-X/instrumentação
9.
Reprod Domest Anim ; 51(1): 59-68, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26660854

RESUMO

BMP-6 has been found to be important to ovarian cells and oocyte, as well as to uterus. Thus, this study investigated the effect of bone morphogenetic protein (BMP-6) and recombinant follicle-stimulating hormone (rFSH) alone or in combination on the in vitro culture (IVC) of isolated caprine secondary follicles (Experiment 1) and the mRNA levels for BMP receptors/Smad signalling pathway (BMPR1A, BMPR2, SMAD1, SMAD4, SMAD5, SMAD6, SMAD7 and SMAD8) in vivo and in vitro using BMP-6 (Experiment 2). Secondary follicles were cultured in αMEM(+) alone (control medium) or supplemented with BMP-6 at 1 or 10 ng/ml and rFSH alone or the combination of both BMP-6 concentrations and rFSH. The results from Experiment 1 showed that the antrum formation rate was higher in the BMP-6 at 1 ng/ml (p < 0.05) than in MEM. In Experiment 2, the mRNA expression for BMPR2, SMAD1, SMAD5 and SMAD6 was detected in non-cultured control and after in vitro culture (MEM and 1 ng/ml BMP-6); while the expression of SMAD7 and SMAD8 mRNA was only detected after IVC, SMAD4 was only detected in the BMP-6 at 1 ng/ml treatment. In conclusion, the low BMP-6 concentration positively influenced antrum formation and ensured normal mRNA expression for BMP receptor and Smads after IVC of caprine secondary follicles.


Assuntos
Proteína Morfogenética Óssea 6/farmacologia , Cabras/fisiologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Transdução de Sinais/efeitos dos fármacos , Animais , Receptores de Proteínas Morfogenéticas Ósseas/genética , Feminino , Hormônio Foliculoestimulante/farmacologia , RNA Mensageiro/análise , Proteínas Recombinantes/farmacologia , Técnicas de Cultura de Tecidos/veterinária
10.
Anim Reprod Sci ; 152: 32-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25496673

RESUMO

A sequential medium with fibroblast growth factor-10 (FGF-10) and follicle stimulating hormone (FSH) was evaluated on the survival, ultrastructure, activation and growth rate of caprine preantral follicles submitted to long-term culture, aiming to establish an ideal in vitro culture system. Ovarian fragments were cultured for 16 days in α-MEM(+) alone or supplemented with FGF-10 and/or FSH added sequentially on different days of culture. Ovarian fragments were cultured during the first (days 0-8) and second (days 8-16) halves of the culture period, generating 10 treatments: α-MEM(+)/α-MEM(+) (cultured control), FSH/FSH, FSH/FGF-10, FSH/FSH+FGF-10, FGF-10/FGF-10, FGF-10/FSH, FGF-10/FSH+FGF-10, FSH+FGF-10/FSH+FGF-10, FSH+FGF-10/FSH and FSH+FGF-10/FGF-10. Follicle morphology, viability and ultrastructure were analyzed. The FSH/FGF-10 treatment showed a higher (P<0.05) percentage of normal follicles compared to all other treatments. In addition, follicles from the FSH/FGF-10 treatment maintained ultrastructural integrity after the culture period. After 16 days of culture, the FSH/FGF-10 and FSH/FSH treatments showed a higher percentage of activation compared to the cultured control (α-MEM(+)/α-MEM(+)). Moreover, the FSH/FGF-10 treatment promoted greater follicular and oocyte diameters compared to the fresh control. In conclusion, this study showed that a sequential medium with FSH followed by FGF-10 (FSH/FGF-10 and FSH/FSH) maintains follicular viability and ultrastructure and promotes transition from the primordial to primary stage (activation) and growth in goat preantral follicles cultured in vitro.


Assuntos
Fator 10 de Crescimento de Fibroblastos/farmacologia , Hormônio Foliculoestimulante/farmacologia , Cabras , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Animais , Meios de Cultura/química , Feminino , Técnicas de Cultura de Tecidos/veterinária
11.
J Hum Hypertens ; 29(6): 366-72, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25339292

RESUMO

The pathophysiological mechanisms of arterial hypertension during hemodialysis (HD) in patients with end-stage renal disease (ESRD) are still poorly understood. The aim of this study is to investigate physiological, cardiovascular and neuroendocrine changes in patients with ESRD and its correlation with changes in blood pressure (BP) during the HD session. The present study included 21 patients with ESRD undergoing chronic HD treatment. Group A (study) consisted of patients who had BP increase and group B (control) consisted of those who had BP reduction during HD session. Echocardiograms were performed during the HD session to evaluate cardiac output (CO) and systemic vascular resistance (SVR). Before and after the HD session, blood samples were collected to measure brain natriuretic peptide (BNP), catecholamines, endothelin-1 (ET-1), nitric oxide (NO), electrolytes, hematocrit, albumin and nitrogen substances. The mean age of the studied patients was 43 ± 4.9 years, and 54.6% were males. SVR significantly increased in group A (P<0.001). There were no differences in the values of BNP, NO, adrenalin, dopamin and noradrenalin, before and after dialysis, between the two groups. The mean value of ET-1, post HD, was 25.9 pg ml(-1) in group A and 13.3 pg ml(-1) in group B (P = < 0.001). Patients with ESRD showed different hemodynamic patterns during the HD session, with significant BP increase in group A, caused by an increase in SVR possibly due to endothelial dysfunction, evidenced by an increase in serum ET-1 levels.


Assuntos
Hipertensão/fisiopatologia , Diálise Renal , Adulto , Idoso , Pressão Sanguínea , Débito Cardíaco , Endotelina-1/sangue , Feminino , Humanos , Hipertensão/sangue , Masculino , Pessoa de Meia-Idade , Neurotransmissores/sangue , Óxido Nítrico/fisiologia , Resistência Vascular
12.
Theriogenology ; 82(1): 27-35, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24725418

RESUMO

This study aimed to demonstrate the expression of growth hormone receptor (GH-R) mRNA and protein in goat ovarian follicles in order to investigate the effects of GH on the survival and development of preantral follicles. The ovaries were processed for the isolation of follicles to study GH-R mRNA expression or to localization of GH-R by immunohistochemical analysis. Pieces of ovarian cortex were cultured for 7 days in minimum essential medium(+) (MEM(+)) in the presence or absence of GH at different concentrations (1, 10, 50, 100, and 200 ng/mL). High expression levels of GH-R mRNA were observed in granulosa/theca cells from large antral follicles. However, preantral follicles do not express mRNA for GH-R. Immunohistochemistry demonstrated that the GH-R protein was expressed in the oocytes/granulosa cells of antral follicles, but any protein expression was observed in preantral follicles. The highest (P < 0.05) rate of normal follicles and intermediate follicles was observed after 7 days in MEM(+) plus 10 ng/mL GH (70%). In conclusion, GH-R mRNA and protein are expressed in caprine antral follicles, but not in preantral follicles. Moreover, GH maintains the survival of goat preantral follicles and promotes the development of primordial follicles.


Assuntos
Cabras/fisiologia , Hormônio do Crescimento/farmacologia , Folículo Ovariano/crescimento & desenvolvimento , Receptores da Somatotropina/metabolismo , Animais , Técnicas de Cultura de Células , Feminino , Cabras/genética , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Folículo Ovariano/efeitos dos fármacos , RNA Mensageiro/metabolismo , Receptores da Somatotropina/fisiologia , Técnicas de Cultura de Tecidos
13.
Proc Biol Sci ; 281(1780): 20133065, 2014 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-24523271

RESUMO

Large oceanic migrants play important roles in ecosystems, yet many species are of conservation concern as a result of anthropogenic threats, of which incidental capture by fisheries is frequently identified. The last large populations of the leatherback turtle, Dermochelys coriacea, occur in the Atlantic Ocean, but interactions with industrial fisheries could jeopardize recent positive population trends, making bycatch mitigation a priority. Here, we perform the first pan-Atlantic analysis of spatio-temporal distribution of the leatherback turtle and ascertain overlap with longline fishing effort. Data suggest that the Atlantic probably consists of two regional management units: northern and southern (the latter including turtles breeding in South Africa). Although turtles and fisheries show highly diverse distributions, we highlight nine areas of high susceptibility to potential bycatch (four in the northern Atlantic and five in the southern/equatorial Atlantic) that are worthy of further targeted investigation and mitigation. These are reinforced by reports of leatherback bycatch at eight of these sites. International collaborative efforts are needed, especially from nations hosting regions where susceptibility to bycatch is likely to be high within their exclusive economic zone (northern Atlantic: Cape Verde, Gambia, Guinea Bissau, Mauritania, Senegal, Spain, USA and Western Sahara; southern Atlantic: Angola, Brazil, Namibia and UK) and from nations fishing in these high-susceptibility areas, including those located in international waters.


Assuntos
Migração Animal , Pesqueiros , Tartarugas/fisiologia , Animais , Oceano Atlântico , Conservação dos Recursos Naturais , Ecossistema , Densidade Demográfica , Dinâmica Populacional
14.
Braz. j. med. biol. res ; 45(12): 1248-1254, Dec. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-659638

RESUMO

Little is known about age-related differences in short-term effects of estradiol on ischemia-reperfusion (I/R) insults. The present study was designed to evaluate the effects of short-term treatment with estradiol on reperfusion arrhythmias in isolated hearts of 6-7-week-old and 12-14-month-old female rats. Wistar rats were sham-operated, ovariectomized and treated with vehicle or ovariectomized and treated with 17β-estradiol (E2; 5 µg·100 g-1·day-1) for 4 days. Hearts were perfused by the Langendorff technique. Reperfusion arrhythmias, i.e., ventricular tachycardia and/or ventricular fibrillation, were induced by 15 min of left coronary artery ligation and 30 min of reperfusion. The duration and incidence of I/R arrhythmias were significantly higher in young rats compared to middle-aged rats (arrhythmia severity index: 9.4 ± 1.0 vs 3.0 ± 0.3 arbitrary units, respectively, P < 0.05). In addition, middle-aged rats showed lower heart rate, systolic tension and coronary flow. Four-day E2 treatment caused an increase in uterine weight. Although E2 administration had no significant effect on the duration of I/R arrhythmias in middle-aged rats, it induced a marked reduction in the rhythm disturbances of young rats accompanied by a decrease in heart rate of isolated hearts. Also, this reduction was associated with an increase in QT interval. No significant changes were observed in the QT interval of middle-aged E2-treated rats. These data demonstrate that short-term estradiol treatment protects against I/R arrhythmias in hearts of young female rats. The anti-arrhythmogenic effect of estradiol might be related to a lengthening of the QT interval.


Assuntos
Animais , Feminino , Arritmias Cardíacas/prevenção & controle , Estradiol/farmacologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Fatores Etários , Arritmias Cardíacas/fisiopatologia , Circulação Coronária/efeitos dos fármacos , Circulação Coronária/fisiologia , Eletrocardiografia , Estradiol/administração & dosagem , Ovariectomia , Ratos Wistar , Função Ventricular Esquerda/efeitos dos fármacos
15.
Braz. j. med. biol. res ; 45(11): 1060-1065, Nov. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-650572

RESUMO

Calcium ion participates in the regulation of neural transmission and the presynaptic release of neurotransmitters. It is also involved in epileptic events, cardiac arrhythmias and abnormal conduction of stimuli. The purpose of the present study was to evaluate the effects of nifedipine, a calcium channel blocker, on epileptic seizures and on reperfusion arrhythmias in rats prone to audiogenic epileptic seizures (Wistar audiogenic rats, WAR) and in normal Wistar rats (N = 6/group). The seizure severity index was applied after an intraperitoneal injection of 20 or 40 mg/kg nifedipine (N20 and N40 groups, respectively). The Langendorff technique was used to analyze cardiac function, as well as the incidence and severity of the reperfusion arrhythmias after ligature and release of the left coronary artery in rats treated or not with nifedipine. We found that nifedipine treatment decreased seizure severity (0.94 ± 0.02 for WAR; 0.70 ± 0.10 for WAR + N20; 0.47 ± 0.08 for WAR + N40) and increased the latent period (13 ± 2 s for WAR; 35 ± 10 s for WAR + N20; 48 ± 7 s for WAR + N40) for the development of seizures in WAR. Furthermore, the incidence and severity of the reperfusion arrhythmias were lower in WAR and normal Wistar rats injected with nifedipine. In WAR, these effects were mediated, at least in part, by a decrease in heart rate. Thus, our results indicate that nifedipine may be considered to be a potential adjuvant drug for epilepsy treatment, especially in those cases associated with cardiac rhythm abnormalities.


Assuntos
Animais , Masculino , Ratos , Antiarrítmicos/uso terapêutico , Anticonvulsivantes/uso terapêutico , Arritmias Cardíacas/tratamento farmacológico , Nifedipino/uso terapêutico , Convulsões/tratamento farmacológico , Estimulação Acústica , Modelos Animais de Doenças , Eletrocardiografia , Epilepsia Reflexa , Ratos Wistar , Índice de Gravidade de Doença
16.
Braz J Med Biol Res ; 45(12): 1248-54, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23108785

RESUMO

Little is known about age-related differences in short-term effects of estradiol on ischemia-reperfusion (I/R) insults. The present study was designed to evaluate the effects of short-term treatment with estradiol on reperfusion arrhythmias in isolated hearts of 6-7-week-old and 12-14-month-old female rats. Wistar rats were sham-operated, ovariectomized and treated with vehicle or ovariectomized and treated with 17ß-estradiol (E2; 5 µg·100 g-1·day-1) for 4 days. Hearts were perfused by the Langendorff technique. Reperfusion arrhythmias, i.e., ventricular tachycardia and/or ventricular fibrillation, were induced by 15 min of left coronary artery ligation and 30 min of reperfusion. The duration and incidence of I/R arrhythmias were significantly higher in young rats compared to middle-aged rats (arrhythmia severity index: 9.4 ± 1.0 vs 3.0 ± 0.3 arbitrary units, respectively, P < 0.05). In addition, middle-aged rats showed lower heart rate, systolic tension and coronary flow. Four-day E2 treatment caused an increase in uterine weight. Although E2 administration had no significant effect on the duration of I/R arrhythmias in middle-aged rats, it induced a marked reduction in the rhythm disturbances of young rats accompanied by a decrease in heart rate of isolated hearts. Also, this reduction was associated with an increase in QT interval. No significant changes were observed in the QT interval of middle-aged E2-treated rats. These data demonstrate that short-term estradiol treatment protects against I/R arrhythmias in hearts of young female rats. The anti-arrhythmogenic effect of estradiol might be related to a lengthening of the QT interval.


Assuntos
Arritmias Cardíacas/prevenção & controle , Estradiol/farmacologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Fatores Etários , Animais , Arritmias Cardíacas/fisiopatologia , Circulação Coronária/efeitos dos fármacos , Circulação Coronária/fisiologia , Eletrocardiografia , Estradiol/administração & dosagem , Feminino , Ovariectomia , Ratos Wistar , Função Ventricular Esquerda/efeitos dos fármacos
17.
Braz J Med Biol Res ; 45(11): 1060-5, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22801414

RESUMO

Calcium ion participates in the regulation of neural transmission and the presynaptic release of neurotransmitters. It is also involved in epileptic events, cardiac arrhythmias and abnormal conduction of stimuli. The purpose of the present study was to evaluate the effects of nifedipine, a calcium channel blocker, on epileptic seizures and on reperfusion arrhythmias in rats prone to audiogenic epileptic seizures (Wistar audiogenic rats, WAR) and in normal Wistar rats (N = 6/group). The seizure severity index was applied after an intraperitoneal injection of 20 or 40 mg/kg nifedipine (N20 and N40 groups, respectively). The Langendorff technique was used to analyze cardiac function, as well as the incidence and severity of the reperfusion arrhythmias after ligature and release of the left coronary artery in rats treated or not with nifedipine. We found that nifedipine treatment decreased seizure severity (0.94 ± 0.02 for WAR; 0.70 ± 0.10 for WAR + N20; 0.47 ± 0.08 for WAR + N40) and increased the latent period (13 ± 2 s for WAR; 35 ± 10 s for WAR + N20; 48 ± 7 s for WAR + N40) for the development of seizures in WAR. Furthermore, the incidence and severity of the reperfusion arrhythmias were lower in WAR and normal Wistar rats injected with nifedipine. In WAR, these effects were mediated, at least in part, by a decrease in heart rate. Thus, our results indicate that nifedipine may be considered to be a potential adjuvant drug for epilepsy treatment, especially in those cases associated with cardiac rhythm abnormalities.


Assuntos
Antiarrítmicos/uso terapêutico , Anticonvulsivantes/uso terapêutico , Arritmias Cardíacas/tratamento farmacológico , Nifedipino/uso terapêutico , Convulsões/tratamento farmacológico , Estimulação Acústica , Animais , Modelos Animais de Doenças , Eletrocardiografia , Epilepsia Reflexa , Masculino , Ratos , Ratos Wistar , Índice de Gravidade de Doença
18.
Reprod Sci ; 19(11): 1219-25, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22562971

RESUMO

We investigated the effect of the leukemia inhibitory factor (LIF) alone or in association with follicle-stimulating hormone (FSH) on the in vitro growth and antrum formation of sheep preantral follicles. To evaluate oocyte quality, parthenogenetic activation of the oocytes recovered from in vitro grown preantral follicles was performed. Preantral follicles >110 µm in diameter were isolated and cultured for 18 days in basic medium either alone (control) or supplemented with LIF (10 or 50 ng/mL) in the absence or presence of FSH. Every 6 days the follicular survival, growth, and antrum formation were evaluated. When compared to control (P < .05), antrum formation was increased in follicles cultured in the presence of LIF10 and FSH. At the end of the culture, the oocytes underwent in vitro maturation (IVM); their viability and chromatin configuration were assessed. Although IVM was not affect by the treatments (P > .05), the numerically highest maturation rates (29.63%) were obtained when follicles were cultured in 50 ng/mL LIF (LIF50). Therefore, their oocytes were submitted to parthenogenetic activation; from which 58.3% of the mature oocytes resulted in 8-cell stage parthenotes. In conclusion, although LIF10 + FSH increases antrum formation when compared to a nonsupplemented medium (minimum essential medium), oocytes from sheep preantral follicles are capable of growing and maturing in vitro independent of LIF addition to the medium, which resulted in the formation of 8-cell parthenotes.


Assuntos
Oócitos/fisiologia , Folículo Ovariano/citologia , Folículo Ovariano/crescimento & desenvolvimento , Partenogênese , Ovinos , Animais , Meios de Cultura , Feminino , Hormônio Foliculoestimulante/farmacologia , Fator Inibidor de Leucemia/farmacologia , Oócitos/efeitos dos fármacos , Oócitos/crescimento & desenvolvimento , Folículo Ovariano/efeitos dos fármacos , Técnicas de Cultura de Tecidos/veterinária
19.
Theriogenology ; 78(4): 907-13, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22541171

RESUMO

The objective was to evaluate the effects of insulin-like growth factor-I (IGF-I) on the quality and fertility of frozen/thawed ovine semen. Five rams (five ejaculates/ram) were used for evaluation of semen parameters. Before cryopreservation, ejaculates were divided into four aliquots and extended with Tris alone or supplemented with human IGF-I (50, 100, or 250 ng/mL). Semen was evaluated immediately after thawing (T0), after 1 h (T1) and 2 h (T2) post-incubation at 37 °C. The percentage of live cells (fluorescence analysis-calcein and ethidium), acrosome integrity (NAR) and motility were analyzed, and hypo-osmotic swelling tests (HOST) were used to evaluate membrane resistance. In addition, AI was performed using 121 ewes to compare the optimal concentration of IGF-I vs. Tris alone on pregnancy rates after laparoscopic insemination. Pregnancy diagnosis was performed by transrectal ultrasonography. After 1 and 2 h post-incubation, in every group, percentage motile sperm, NAR and HOST decreased compared to semen at T0. Motility was higher (P < 0.05) in the IGF-I 100 and IGF-I 250 groups when compared to the IGF-I 50 and Tris groups (76.2 and 74.4% vs. 66.2 and 64.4 percent, respectively) at T0, after 1 h (67 and 63.6% vs. 56.2 and 54.7%) and 2 h post-incubation (58.2 and 55.8% vs. 48 and 47.2%). Furthermore, viability was higher (P < 0.05) in the insulin-like growth factor-I (IGF-I) 100 and IGF-I 250 groups than in the IGF-I 50 and Tris groups (88.7 and 88.3% vs. 76.6 and 77.6%, respectively) at T0. There was no difference (P > 0.05) in NAR or hypo-osmotic swelling tests (HOST) among groups. There were no differences (P > 0.05) in fertility between the IGF-I 100 and Tris groups. In conclusion, IGF-I improved subjective sperm motility and structural integrity of the plasma membrane without a significant effect on 45-day pregnancy rates after laparoscopic insemination of ewes with frozen-thawed semen.


Assuntos
Criopreservação , Fertilidade/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/farmacologia , Preservação do Sêmen , Sêmen/efeitos dos fármacos , Ovinos , Acrossomo/efeitos dos fármacos , Acrossomo/fisiologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Criopreservação/veterinária , Avaliação Pré-Clínica de Medicamentos , Feminino , Fertilidade/fisiologia , Inseminação Artificial/veterinária , Masculino , Pressão Osmótica/efeitos dos fármacos , Pressão Osmótica/fisiologia , Gravidez , Taxa de Gravidez , Sêmen/citologia , Sêmen/fisiologia , Análise do Sêmen/veterinária , Preservação do Sêmen/efeitos adversos , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Ovinos/fisiologia
20.
Reprod Domest Anim ; 47(1): 20-5, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21518029

RESUMO

This study quantified Fibroblast growth factor 2 (FGF-2) mRNA and localized FGF-2 protein in different categories of follicles isolated from goat ovaries. In addition, we verified the effects of this factor on the in vitro culture of preantral follicles isolated from goats. For mRNA quantification, we performed real-time PCR using primordial, primary and secondary follicles, as well as cumulus-oocyte complexes (COCs) and mural granulosa and theca cells of small and large antral follicles. For FGF-2 protein localization, the ovaries were subjected to conventional immunohistochemical procedures. Preantral follicles were isolated and cultured in vitro for 12 days in either control (basic) or supplemented with FGF-2 medium. The expression of FGF-2 mRNA was detected in all categories of follicles and there was no difference in preantral follicles and COCs or granulosa/theca cells from small and large antral follicles. However, in large antral follicles, COCs showed expression levels significantly lower than in granulosa/theca cells (p < 0.05). We observed moderate expression of FGF-2 protein in preantral follicles but not in granulosa cells of primordial follicles and theca cells of secondary follicles. In both small and large antral follicles, strong, moderate and weak staining was observed in oocytes, granulosa and theca cells, respectively. The addition of FGF-2 caused a significant increase in the daily follicular growth rate compared to the control group. We conclude that FGF-2 mRNA is expressed throughout follicular development and that its protein can be found in different patterns in preantral and antral follicles. Furthermore, FGF-2 increases the follicular growth rate in vitro.


Assuntos
Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/farmacologia , Expressão Gênica , Cabras , Folículo Ovariano/fisiologia , Ovário/química , Animais , Células Cultivadas , Meios de Cultura , Células do Cúmulo/fisiologia , Feminino , Fator 2 de Crescimento de Fibroblastos/análise , Imuno-Histoquímica , Folículo Ovariano/química , Folículo Ovariano/efeitos dos fármacos , RNA Mensageiro/análise , Reação em Cadeia da Polimerase em Tempo Real/veterinária
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