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1.
Environ Monit Assess ; 196(4): 334, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430330

RESUMO

Reptiles are the least studied vertebrates regarding the impact of pesticides on their health, despite being good models for ecotoxicological studies given their abundance and easy handling. Salvator merianae is widely distributed in South America and often found in agricultural cultivation areas. Here, we compared the morphological, biochemical, and physiological parameters of S. merianae from an exposed area (EA) to pesticides and a reference area (RA) or control. These parameters were measured in plasma (albumin, alanine transaminase, alkaline phosphatase, gamma-glutamyl transpeptidase, glucose, total proteins, uric acid, triglycerides, VLDL, and corticosterone) and in erythrocytes (TBARS, glutathione S-transferase, superoxide dismutase, and catalase activity). Blood samples were collected from 28 lizards (EA: three juveniles, three adult females, and three adult males; RA: nine juveniles, four females, and five males) in southern Brazil during the reproductive period. We observed a decrease in body mass, the ratio between body mass and total length and snout-vent length in juvenile lizards collected at EA. The levels of TBARS, glutathione S-transferase, triglycerides, VLDL, and uric acid were altered for juveniles in EA. When comparing the two areas, females differed in superoxide dismutase activity and total proteins, while males differed in superoxide dismutase, catalase, and glutathione S-transferase activity. This set of results shows that S. merianae, especially juveniles, suffers a negative impact when inserted in an agricultural area. The analyzed biomarkers proved suitable for monitoring these lizards and the quality of this environment.


Assuntos
Lagartos , Praguicidas , Animais , Feminino , Masculino , Praguicidas/toxicidade , Praguicidas/metabolismo , Catalase/metabolismo , Lagartos/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Ácido Úrico/metabolismo , Monitoramento Ambiental , Superóxido Dismutase/metabolismo , Glutationa Transferase/metabolismo , Triglicerídeos/metabolismo , Brasil
2.
J Appl Microbiol ; 131(1): 460-469, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33289232

RESUMO

AIMS: The objective of this study was to evaluate the effect of treatment with the probiotic Saccharomyces boulardii with or without metronidazole in experimental giardiasis. METHODS AND RESULTS: The effect of treatment with S. boulardii with or without metronidazole on the intestinal mucosa, the antioxidant defence system and the parasitic load was determined in experimental giardiasis. Eight groups of animals with infection and/or treatment with the probiotic and/or drugs for 1 week after infection with Giardia lamblia were used. A reduction of approximately 90% in the parasitic load was observed in all the treated groups. Saccharomyces boulardii attenuated the damage caused by infection in the intestinal mucosa preserving its architecture and inhibiting the oxidative stress induced by parasite and metronidazole. CONCLUSIONS: Saccharomyces boulardii was effective alone or in combination with metronidazole in resolving already established G. lamblia infection. SIGNIFICANCE AND IMPACT OF THE STUDY: These results suggest the use of S. boulardii as an alternative treatment for giardiasis mainly in cases of resistance or intolerance to conventional treatment.


Assuntos
Antiprotozoários/uso terapêutico , Giardíase/tratamento farmacológico , Probióticos/uso terapêutico , Saccharomyces boulardii/fisiologia , Animais , Modelos Animais de Doenças , Gerbillinae , Giardia lamblia/efeitos dos fármacos , Giardíase/parasitologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/parasitologia , Metronidazol/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Carga Parasitária , Probióticos/farmacologia
3.
Benef Microbes ; 9(5): 789-797, 2018 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-30165752

RESUMO

The aim of the study was to assess the efficacy of Saccharomyces boulardii in experimental treatment of giardiasis and its impact on intestinal integrity and some functions of gerbils infected with Giardia lamblia. 28 gerbils (Meriones unguiculatus), aged 4-6 weeks, were divided into four groups: untreated and uninfected control (CT); infected with G. lamblia (IGL); treated with S. boulardii (SB); and infected with G. lamblia and treated with S. boulardii (ITSB). The SB and ITSB groups received S. boulardii 15 days prior to being infected with G. lamblia. The treatment continued until completion of the experiment (22nd day). The IGL and ITSB groups were gavage-inoculated with G. lamblia ensuring one-week infection. 4 h before euthanasia, all animals were gavaged with a solution containing diethylenetriamine-pentaacetic acid (DTPA) marked with technetium-99mTc DTPA to determine intestinal permeability. The small intestine was removed for histopathological, morphometric analysis and count of trophozoites adhered to the mucosa. The selected probiotic caused an approximate reduction of 70% of parasite load, which was determined by attached trophozoites (P<0.01) and immune-marked trophozoites (P<0.05). Treatment with S. boulardii (SB and ITSB groups) also increased the height of the intestinal villi and crypt depth compared to the CT and IGL groups (P<0.05). The area of mucus production and the number of goblet cells of the SB and ITSB groups were higher compared to the CT and IGL groups (P<0.01). The animals treated with S. boulardii also exhibited a significant increase of intraepithelial lymphocytes counts (P<0.01). There was no difference in the intestinal permeability between the groups studied. The efficacy of S. boulardii in reducing damages caused by Giardia was demonstrated, with an approximate reduction of 70% of the parasite load, suggesting its use as a coadjuvant in giardiasis treatment.


Assuntos
Giardia lamblia/fisiologia , Giardíase/tratamento farmacológico , Probióticos/administração & dosagem , Saccharomyces boulardii/fisiologia , Animais , Modelos Animais de Doenças , Gerbillinae , Giardia lamblia/efeitos dos fármacos , Giardia lamblia/crescimento & desenvolvimento , Giardíase/parasitologia , Humanos , Intestino Delgado/parasitologia , Intestino Delgado/patologia , Masculino
4.
Arq. bras. med. vet. zootec. (Online) ; 70(5): 1403-1408, set.-out. 2018. ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-946865

RESUMO

Relata-se um caso de pneumomediastino, pneumotórax e enfisema subcutâneo em um cão com pneumopatia associada à cinomose. As queixas principais eram tosse, secreção nasal purulenta, apatia e enfisema subcutâneo em face, região cervical e torácica. O exame radiográfico evidenciou pneumomediastino, pneumotórax e broncopneumopatia grave com áreas de consolidação pulmonar. Teste rápido imunocromatográfico para detecção de antígeno da cinomose foi positivo e houve melhora dos sinais respiratórios com antibioticoterapia, porém o quadro evoluiu para alterações neurológicas. De acordo com a revisão de literatura realizada, não há casos semelhantes relatados.(AU)


A case of pneumomediastinum, pneumothorax and subcutaneous emphysema in a dog with pneumopathy associated to distemper is reported. The main complaints were cough, purulent nasal discharge, lethargy and subcutaneous emphysema in the face, neck, and chest area. Radiographic examination showed pneumomediastinum, pneumothorax, and severe bronchopneumopathy with areas of pulmonary consolidation. Rapid test for canine distemper antigen detection was positive. After the antibiotic therapy there was an improvement of respiratory signs; however, the patient developed neurological symptomatology. As far as the author´s knowledge by literature review carried out, there are no similar cases reported.(AU)


Assuntos
Animais , Cães , Cinomose , Pneumopatias/veterinária , Enfisema Mediastínico/veterinária , Diagnóstico de Pneumomediastino , Pneumotórax/veterinária
5.
Physiol Behav ; 165: 55-68, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27378507

RESUMO

Studies in our laboratory have characterized the putative neuromodulatory effects of a standardized extract of the green leaves of Ginkgo biloba (EGb), which comprises a formulation of 24% ginkgo-flavoglycosides and 6% ginkgo-terpenoid lactones, on conditioned suppression. This model comprises a suitable animal model for investigating the behavioral changes and pharmacological mechanisms that underlie fear memory and anxiety. The characterization of the effects on distinct stages of fear memory or fear extinction will help illustrate both the beneficial and harmful effects. Three hundred adult male Wistar rats were randomly assigned to 30 groups according to the treatment as follows: i-ii) control groups (CS-US and CSno-US); iii) vehicle group (12% Tween®80); and iv-vi) EGb groups (250, 500 and 1000mgkg(-1)); or experimental procedures designed to assess the effects of EGb treatment prior to the acquisition (n=20 per group) and retrieval of conditioned fear (n=10 per group) or prior to the extinction training (n=10 per group) and extinction retention test (n=10 per group). Furthermore, to better understand the effects of acute EGb treatment on fear memory, we conducted two additional analyses: the acquisition of within- and between-session extinction of fear memory (short- and long-term memory, respectively). No difference was identified between the control and treatment groups during the retention test (P>0.05), with the exception of the CSno-US group in relation to all groups (P<0.05). A between-session analysis indicated that EGb at 250mgkg(-1) facilitated the acquisition of extinction fear memory, which was verified by the suppression ration in the first trial of extinction training (SR=0.39) and the extinction retention test session (SR=0.53, P<0.05), without impairments in fear memory acquisition, which were evaluated during the retention test (SR=0.79). Moreover, EGb administered at 1000mgkg(-1) prior to conditioning did not enhance the long-term extinction memory, i.e., it did not prevent the return of extinguished fear memory in the extinction retention test, in which the spontaneous recovery of fear was demonstrated (SR=0.63, P<0.05); however, it significantly facilitated short-term memory as verified by data from the within-session extinction (1 to 8-10 trials) during the retention test (SR=0.73 to SR=0.59; P<0.05) and the extinction retention test (SR=0.63 to SR=0.41; P<0.05). Moreover, spontaneous recovery was identified in response to a higher dose of EGb when administered prior to extinction training (SR=0.75, P<0.05) and the extinction retention test (SR=0.70; P<0.05). At dose of 500mgkg(-1) EGb reduced the suppression ratio when administered prior to the retention test (SR=0.57) and extinction training (SR=0.55; P<0.05) without preventing the acquisition of fear memory, which suggests that EGb has anti-anxiety effects. Taken together, the current findings suggest that EGb differentially modulates short- and long-term memory, as well as anxiety-like behavior. The actions of EGb may provide information regarding the beneficial effects in the prevention and treatment of neurocognitive impairments and anxiety disorders. Additional analyses are necessary to facilitate an understanding of these effects; however, previous data from our group suggest that GABAergic, serotoninergic and glutamatergic receptors are potential targets of the effects of EGb on conditioned suppression.


Assuntos
Extinção Psicológica/efeitos dos fármacos , Ginkgo biloba , Memória de Longo Prazo/efeitos dos fármacos , Memória de Curto Prazo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Psicotrópicos/farmacologia , Animais , Ansiedade/tratamento farmacológico , Condicionamento Psicológico/efeitos dos fármacos , Relação Dose-Resposta a Droga , Medo/efeitos dos fármacos , Masculino , Modelos Animais , Atividade Motora/efeitos dos fármacos , Distribuição Aleatória , Ratos Wistar , Fatores de Tempo
6.
Zootaxa ; 4013(1): 143-6, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26623889

RESUMO

The genus Lumahyphes Molineri, 2004 (Ephemeroptera: Leptohyphidae) currently is comprised of three species. Lumahyphes cocal sp. nov. is described based on material from the state of Roraima in northern Brazil. The new species differs from the other described species by having the following combination of characteristics: greyish wing membrane; terga base color whitish and terga I-III & VIII-X washed completely with gray; dorsal structure of penes rounded; spines of penes S-shaped in lateral view; and apex of spines directed anteriorly.


Assuntos
Ephemeroptera/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Ephemeroptera/anatomia & histologia , Ephemeroptera/crescimento & desenvolvimento , Masculino , Tamanho do Órgão
7.
Arq. bras. med. vet. zootec ; 66(6): 1787-1794, 12/2014. tab, graf
Artigo em Português | LILACS | ID: lil-735771

RESUMO

Objetivou-se com este trabalho descrever as medidas biométricas de cordeiros lactantes da raça Santa Inês criados em condições amazônicas; estabelecer relação entre a idade e as medidas corporais; bem como correlacionar essas medidas biométricas com o peso corporal. Utilizaram-se 75 animais criados em sistema semi-intensivo, submetidos a mensurações do peso corporal (PC), comprimento corporal (CC), altura do anterior (AA) e do posterior (AP), perímetro torácico (PT), largura da garupa (LG) e do peito (LP), comprimento da perna (CP), perímetro da perna (PP) e compacidade corporal (COMPC), ao nascer e aos 15, 30, 45 e 60 dias de idade. Somente as medidas LG e PP demonstraram regressões com R2 abaixo de 0,70 em relação à idade dos cordeiros. Todas as medidas corporais utilizadas nesta pesquisa, individualmente, demonstraram r positivo com o peso corporal. As variáveis biométricas que melhor compuseram a equação de predição do peso dos cordeiros utilizados neste estudo foram CC, AP, PT, LG e PP. Concluiu-se que a idade de cordeiros pode ser utilizada como preditora do peso e de algumas medidas biométricas corporais e que o peso pode ser estimado por meio de algumas medidas biométricas...


This study aimed to 1) describe the biometric measurements of Santa Inês lambs until weaning, when raised in the Amazonia conditions; 2) establish the relationship between age and body measurements; and 3) correlate these biometric measurements to body weight. 75 animals submitted to semi-intensive breeding were used, and underwent measurements of body weight (BW), body length (BL), height of the forelimb (HF) and hindlimb (HH), thoracic perimeter (TP), width of rump (WR) and chest (WC), length of leg (LL), perimeter of leg (PL) and more body compacity (COMP), at birth and at 15, 30, 45 and 60 days of age. As a result, the WR and PL measurements demonstrated regressions with R2 below 0.70 in relation to age of lambs. All biometrical measurements used in this study individually demonstrated positive r with body weight. Biometric variables that compose the equation for predicting weight of lambs used in this study were BL, HH, TP, WR and PL. It was concluded that the age of lambs can be used as a predictor of weight and some body biometric measurements. The weight can also be estimated by some biometric measurements...


Assuntos
Animais , Identificação Biométrica/estatística & dados numéricos , Identificação Biométrica/métodos , Ovinos/anatomia & histologia , Ovinos/crescimento & desenvolvimento , Biometria/métodos , Pesos e Medidas Corporais/estatística & dados numéricos , Pesos e Medidas Corporais/veterinária
8.
Neuroscience ; 235: 70-86, 2013 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-23321541

RESUMO

Our group previously demonstrated that short-term treatment with a standardized extract of Ginkgo biloba (EGb) changed fear-conditioned memory by modulating gene expression in the hippocampus, amygdaloid complex and prefrontal cortex. Although there are few controlled studies that support the long-term use of EGb for the prevention and/or treatment of memory impairment, the chronic use of Ginkgo is common. This study evaluated the effects of chronic treatment with EGb on the conditioned emotional response, assessed by the suppression of ongoing behavior and in the modulation of gene and protein expression. Male adult Wistar rats were treated over 28days and assigned to five groups (n=10) as follows: positive control (4mgkg(-1) Diazepam), negative control (12% Tween 80), EGb groups (0.5 and 1.0gkg(-1)) and the naïve group. The suppression of the licking response was calculated for each rat in six trials. Our results provide further evidence for the efficacy of EGb on memory. For the first time, we show that long-term treatment with the highest dose of EGb improves the fear memory and suggests that increased cAMP-responsive element-binding protein (CREB)-1 and glial fibrillary acidic protein (GFAP) mRNA and protein (P<0.001) in the dorsal hippocampus and amygdaloid complex and reduced growth and plasticity-associated protein 43 (GAP-43) (P<0.01) in the hippocampus are involved in this process. The fear memory/treatment-dependent changes observed in our study suggest that EGb might be effective for memory enhancement through its effect on the dorsal hippocampus and amygdaloid complex.


Assuntos
Tonsila do Cerebelo/fisiologia , Condicionamento Operante/efeitos dos fármacos , Ginkgo biloba/química , Hipocampo/fisiologia , Neuroglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Tonsila do Cerebelo/citologia , Tonsila do Cerebelo/efeitos dos fármacos , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/biossíntese , Interpretação Estatística de Dados , Diazepam/farmacologia , Medo/efeitos dos fármacos , Proteína GAP-43/biossíntese , Proteína Glial Fibrilar Ácida/biossíntese , Proteína Glial Fibrilar Ácida/genética , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipnóticos e Sedativos/farmacologia , Imuno-Histoquímica , Masculino , Memória/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Extratos Vegetais/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Wistar
9.
Dis Esophagus ; 17(1): 1-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15209735

RESUMO

Eponyms are frequently used in the surgery in homage to remarkable surgeons, specially creators of new surgical techniques and instruments. Sometimes, however, the right person is not revered or the name persists, but the author's technique has been changed over time and the original procedure is lost. Eponyms of the 10 most famous procedures in esophageal surgery are revisited. Names like Lortat-Jacob, Toupet, Dor, Heller, Nissen, Ivor Lewis, Collis, Merendino, Hill, and Belsey, are reviewed, analyzing the man behind the name, the original technique and its modifications.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/história , Epônimos , Doenças do Esôfago/cirurgia , Doenças do Esôfago/história , História do Século XX , Humanos
10.
Atherosclerosis ; 154(1): 71-7, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11137084

RESUMO

The effect of gelatin ingestion on cholesterol metabolism and on atheroma formation was evaluated in both wild type (n=14) and apoprotein E (apoE) knock out (apoE(-/-)) (n=20) C57BL/6 7-week-old mice. Animals were fed a cholesterol-free isoproteic semi-purified diet containing 20% of casein (control diet) or 10% of casein plus 10% of gelatin (gel diet) for 8 weeks. In wild type mice, dietary gelatin caused a reduction in the serum triacylglycerols levels associated with an increase in the fecal excretion. No difference in blood cholesterol was seen at the sixth week of experiment. At the eighth week of experiment, there was a modest but significant reduction of serum total and high density lipoprotein (HDL) cholesterol in apoE(-/-) mice fed on gel diet compared to the control. Total cholesterol/HDL cholesterol ratio was 2-fold higher in the gel group than that seen in the control group (14.39 and 7.84, respectively). Histological analyzes showed a 2.2-fold increase in the dimension of the atherosclerotic plaques in the proximal aorta in apoE(-/-) mice fed on a gel diet compared to those fed on a control diet. The gel diet also promoted a reduction in the fecal excretion of bile acids. Hepatic cholesterol was similar in both groups. In conclusion, although gelatin reduced total serum cholesterol, this reduction was associated to a decrease of HDL cholesterol and consequent increase of total cholesterol/HDL cholesterol ratio, resulting in an acceleration of atherogenesis.


Assuntos
Apolipoproteínas E/deficiência , Arteriosclerose/etiologia , Gelatina/administração & dosagem , Animais , Aorta/efeitos dos fármacos , Aorta/patologia , Apolipoproteínas E/genética , Arteriosclerose/patologia , Caseínas/administração & dosagem , Caseínas/farmacologia , Colesterol/sangue , HDL-Colesterol/antagonistas & inibidores , HDL-Colesterol/sangue , Dieta , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout/genética , Farmacologia
11.
J Mater Sci Mater Med ; 12(6): 543-8, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15348271

RESUMO

The adhesion of coagulase negative Staphylococcus epidermidis expressing capsular polysaccharide/adhesin (PS/A) to cellulose diacetate (CDA), as well as to primary reference low-density polyethylene, was assessed in vitro. Attached bacteria were released by gentle sonication and quantified as colony forming units. Surface free energy of cells and materials and the free energy of interaction between cells, each type of material and water molecules was calculated through contact angle measurement, also enabling the determination of materials surface hydrophobicity. The influence of CDA surface modification by deacetylation and phosphorylation on bacterial adhesion was studied. Chemical modifications of CDA by deacetylation and by phosphorylation were effective in lowering bacterial adhesion.

12.
Rev. Inst. Med. Trop. Säo Paulo ; 41(3): 155-8, May-Jun. 1999. tab
Artigo em Inglês | LILACS | ID: lil-240782

RESUMO

A importancia clinica e de saude publica de resultados indeterminados em exames para HIV-1/2 e ainda dificil de avaliar em doadores de sangue voluntarios. Na Fundacao Hemominas e utilizado um teste de triagem (ELISA) que, se reativo, e seguido pelo Western blot (WB). Avaliamos nesse estudo 84 doadores que apresentavam ELISA repetidamente reativo, mas WB indeterminado. Dos 84 individuos, 16 (19 por cento) tinham historia de doencas sexualmente transmissiveis; 18/84 (21,4 por cento) informaram ter recebido ou pago por sexo; 3/84 (3,6 por cento) informaram contacto homosexual; 2/26 mulheres (7,6 por cento) tinham historia pregressa de multiplos abortos ilegais e 3/84 (3,6 por cento) tinham sidos transfundidos. Quatro de 62 doadores (6,5 por cento) tinham fator anti-nuclear (Hep2) positivo, com titulos de ate 1:640. Exame parasitologico revelou a presenca de ovos de S. mansoni nas fezes de 4/62 (6,4 por cento) e outros parasitas em 8/62 (12,9 por cento). Cinco individuos (5,9 por cento) apresentaram franca conversao para HIV-1/2 no WB; 43/84 (51,2 por cento) tinham resultados negativos na ultima visita, enquanto que 36/84 (42,9 por cento) permaneceram com o WB inderterminado. Concluimos que, embora pudessemos encontrar algumas condicoes associadas ao resultado inderminado para HIV-1/2 no WB e muitos doadores com historia pregressa de comportamento de risco, o significado da maioria dos resultados ainda necessita elucidacao


Assuntos
Humanos , Doadores de Sangue , Western Blotting , Seguimentos , Infecções por HIV/prevenção & controle , Brasil , Infecções por HIV/epidemiologia , Assunção de Riscos
13.
Transfus Sci ; 19(1): 39-43, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10182182

RESUMO

Testing blood donors for the human immunodeficiency viruses (HIV-1 and 2), requires serological tests that are frequently inconclusive. Peripheral blood mononuclear cells of 50 blood donors with the screening test (ELISA) reactive to HIV-1, but with indeterminate results in the first Western Blot (WB) performed, were submitted to the polymerase chain reaction (PCR) and heteroduplex mobility assay (HMA), a nonsequencing method that can distinguish between HIV-1 subtypes (A to I). PCR amplification of HIV-1 env gene regions has been obtained in 12 (24.0%) samples. HMA of the amplified DNA showed that 12 belonged to HIV-1 B subtype and one to F subtype. PCR testing of the amplified DNA helped to elucidate doubtful serological results and HMA proved to be a relatively simple and rapid way of subtyping HIV-1 for epidemiological purposes.


Assuntos
Doadores de Sangue , Genes env , HIV-1/isolamento & purificação , Ácidos Nucleicos Heteroduplexes/genética , Testes Sorológicos/métodos , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , HIV-1/genética , Humanos , Masculino , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes
14.
Hypertension ; 27(6): 1284-90, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8641737

RESUMO

We have recently shown that an angiotensin-(1-7) [Ang-(I-7)] analogue, D-Ala7-Ang-(1-7) (A-779), is a selective Ang-(1-7) antagonist with no significant action on angiotensin type 1 or type 2 receptors. The availability of selective angiotensin antagonists prompted us to evaluate the role of Ang-(1-7) and Ang II on central modulation of the baroreflex control of heart rate in normotensive Wistar rats and spontaneously hypertensive rats (SHR). Blood pressure recording and reflex changes in heart rate elicited by intravenous bolus injections of phenylephrine were made before and within 1 and 3 hours of intracerebroventricular (ICV, lateral ventricle) infusion of saline (8 microL/h), A-779 (4 microg/h), DuP 753 (100 microg/h), or CGP 42112A (50 mu g/h) in conscious rats. The slope of the relationship between changes in pulse interval versus changes in mean arterial pressure was used as an index of the baroreflex control of heart rate. ICV infusion of saline or any of the antagonists did not significantly change basal levels of mean arterial pressure and heart rate in SHR (170 +/- 6 mm Hg nd 360 +/- 9 beats per minute, respectively; n = 29) or Wistar rats (108 +/- 2 mm Hg and 377 +/- 6 beats per minute, respectively; n=29). Three hours of ICV infusion of A-779 markedly decreased baroreflex sensitivity in Wistar rats (from a basal slope of 1.09 +/- O.3). In contrast, A-779 did not significantly alter the depressed baroreflex sensitivity of SHR (0.61 +/- O.l). ICV infusion of DuP 753 produced a significant increase (60 percent) in baroreflex control of heart rate in both Wistar rats and SHR. Saline or CGP 42112A infusions did not significantly alter baroreflex control of heart rate. These results suggest that endogenous Ang II and Ang-(1-7) are differentially affecting central baroreflex modulation, acting probably through distinct receptor subtypes. Although the central Ang II inhibitory effect is mediated by the type 1 receptor subtype, the facilitatory effect of Ang-(1-7) might be mediated by a different, unidentified receptor.


Assuntos
Angiotensina II/antagonistas & inibidores , Anti-Hipertensivos/farmacologia , Barorreflexo/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Angiotensina II/análogos & derivados , Angiotensina II/farmacologia , Animais , Compostos de Bifenilo/farmacologia , Imidazóis/farmacologia , Losartan , Masculino , Oligopeptídeos/farmacologia , Fragmentos de Peptídeos/farmacologia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Tetrazóis/farmacologia
15.
Brain Res Bull ; 35(4): 293-8, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7850477

RESUMO

In this study we describe a new angiotensin antagonist [Asp1-Arg2-Val3-Tyr4-Ile5-His6-D-Ala7, (A-779)] selective for the heptapeptide angiotensin-(1-7) [Ang-(1-7)]. A-779 blocked the antidiuretic effect of Ang-(1-7) in water-loaded rats and the changes in blood pressure produced by Ang-(1-7) microinjection into the dorsal-medial and ventrolateral medulla. In contrast, A-779 did not change the dipsogenic, pressor, or myotropic effects of angiotensin II (Ang II). Also, A-779 did not affect the antidiuretic effect of vasopressin or the contractile effects of angiotensin III, bradykinin, or substance P on the rat ileum. In the rostral ventrolateral medulla, the pressor effect produced by Ang-(1-7) microinjection was completely blocked by A-779 but not by AT1 or AT2 receptor antagonists (DUP 753 and CGP 42112A, respectively). Conversely, the pressor effect produced by Ang II was not changed by A-779 but was completely blocked by DUP 753. Binding studies substantiated these observations: A-779 did not compete significantly for 125I-Ang II binding to adrenocortical membranes at up to a 1 microM concentration. Low affinity binding was also observed in adrenomedullary membranes with an IC50 greater than 10 microM. Our results show that A-779 is a potent and selective antagonist for Ang-(1-7). More importantly, our data indicate that specific angiotensin receptors mediate the central and peripheral actions of Ang-(1-7).


Assuntos
Angiotensina II/análogos & derivados , Angiotensina II/antagonistas & inibidores , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/farmacologia , Receptores de Angiotensina/metabolismo , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/metabolismo , Sequência de Aminoácidos , Angiotensina I , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Antagonistas de Receptores de Angiotensina , Animais , Pressão Sanguínea/efeitos dos fármacos , Diurese/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Técnicas In Vitro , Injeções Intraventriculares , Masculino , Bulbo/efeitos dos fármacos , Dados de Sequência Molecular , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Fragmentos de Peptídeos/metabolismo , Ratos , Ratos Wistar , Receptores de Angiotensina/efeitos dos fármacos , Contração Uterina/efeitos dos fármacos
16.
Artigo em Português | MEDLINE | ID: mdl-8235270

RESUMO

In 190 patients with malignant gastric neoplasia the value of laparoscopy for diagnosing intra-abdominal metastases was investigated. At the laparoscopic examination the presence of tumoral tissue was appraised on the serosal coat of the stomach, epiploons, parietal and visceral peritoneum, and in the liver. On hand of laparoscopic findings (peritoneal or hepatic metastases) the surgical treatment was discarded in 34 patients (70.6%). In the remaining 29.4% of patients a bad general condition or concomitant diseases contra-indicated surgical intervention. A comparison of laparoscopic and surgical findings showed that correct diagnosis was established by laparoscopy in 61.4% of cases with tumoral invasion of gastric serosa, in 21.4% of cases with involvement of epiploon, in 27% of parietal peritoneum, and in 33.3% of the liver. Falsely positive findings were rare (5% of examinations).


Assuntos
Laparoscopia/métodos , Neoplasias Gástricas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
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