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3.
Braz. j. biol ; 76(3): 743-749, tab, graf
Article in English | LILACS | ID: lil-785025

ABSTRACT

Abstract Many aspects of sex change in reef fishes have been studied, including behavior and social organization. However, gonad histology remains the most robust way to identify sexual patterns in fishes. Some uncommon tissues remain poorly described, such as the accessory gonadal structures found in species from the Gobiidae family, which are rare in other bony fishes. This is the first report of the testicular gland in Gramma brasiliensis and for the Grammatidae family. Between April 2011 and February 2012 eighty specimens were collected during four dive campaigns on the Taipus de Fora reef (13°56’20”S 38°55’32”W), Bahia, Northeast Brazil, and their sex was determined. Thirteen per cent of the active-females and 90% of the active-males had testicular gland tissue in their ovotestis. This discovery led to additional research into the characteristics of the gland tissue and its relationship with gonadal maturation. Three patterns of testicular gland development were found in Brazilian basslet ovotestis. Both ova and sperm-producing gonad contained testicular gland tissue, and the appearance of this tissue seems to be the first modification of ovotestis tissue marking the beginning of the protogynous sex-change process in G. brasiliensis.


Resumo Diversos aspectos da troca de sexo em peixes recifais vem sendo estudados, incluindo comportamentos e organização social. Entretanto, a histologia das gônadas continua sendo a maneira mais robusta para se identificar padrões sexuais em peixes. Alguns tecidos incomuns, tais como as estruturas anexas a gônada encontradas em espécies da família Gobiidae e raras em outras espécies são pouco estudados. Este trabalho é a primeira descrição da glândula testicular em Gramma brasiliensis e para a família Grammatidae. Entre abril de 2011 e fevereiro de 2012, oitenta espécimes foram coletados durante quatro amostragens no recife de Taipus de Fora (13°56’20”S 38°55’32”W), Bahia, Brasil, e tiveram seus sexos determinados. Treze por cento das fêmeas ativas e noventa por cento dos machos ativos apresentaram tecido da glândula testicular em suas gônadas. Esta descoberta levou ao estudo da características dessa estrutura e sua relação com a maturação gonadal. Foram identificados três padrões de desenvolvimento da glândula testicular nas gônadas do Gramma brasiliensis. Tanto as gônadas produtoras de espermatozoides quanto as de oócitos apresentaram tecido da glândula testicular, e o surgimento desse tecido parece ser a primeira modificação gonadal do início da troca de sexo protogínica em G. brasiliensis.


Subject(s)
Animals , Male , Female , Testis/physiology , Perciformes/physiology , Adaptation, Physiological/physiology , Hermaphroditic Organisms/physiology , Brazil , Gonads/physiology
4.
Article in Portuguese | LILACS | ID: lil-718810

ABSTRACT

A terapia antineoplásica tradicional apresenta algumas limitações que podem ser superadas através da utilização dos lipossomas. Estes nanossistemas de carreamento possibilitam o direcionamento de fármacos e reduzem efeitos secundários. Alguns peptídeos catiônicos sintetizados na pele de anuros apresentam atividade citotóxica seletiva (microorganismos e/ou tumores). Neste sentido, espécies do gênero Phyllomedusa secretam as dermaseptinas. Objetivou-se neste estudo, avaliar a citotoxicidade in vitro da dermaseptina 01 (DS 01) livre e encapsulada em lipossomas unilamelares pequenos (SUVs) em células tumorais humanas. Os lipossomas foram preparados pelo método de hidratação do filme lipídico seguido de sonicação. Foram produzidas formulações neutras e catiônicas, convencionais e furtivas. A citotoxicidade foi analisada em células tumorais de pulmão (NCI-H292), cólon (HT-29) e laringe (HEp-2), pelo ensaio de redução do sal tetrazólio (MTT) em placas de 96 poços. Os lipossomas foram submetidos a testes de estabilidade acelerada e em longo prazo. Em NCI-H292, a DS 01 livre apresentou efeito citostático médio de 35,6%. A encapsulação do peptídeo em lipossomas convencionais neutros aumentou o efeito, ao contrário dos furtivos. Para HT-29 e HEp-2, a DS 01 livre inibiu o crescimento celular em aproximadamente 50%, em média. A encapsulação em lipossomas catiônicos potencializou o efeito; os lipossomas convencionais inibiram na faixa de 80% e os furtivos, mais que 95% para as duas linhagens celulares. A DS 01, um peptídeo catiônico antimicrobiano, apresentou efeito citotóxico in vitro para células tumorais humanas que foi potencializado com a nanoencapsulação...


The conventional anticancer therapies show some limitations that can be overcome by using liposomes. This type of nanocarriers allows preferential targeting of drugs and reduces undesirable secondary effects. Some cationic peptides synthesized by the skin of anurans exhibit selective cytotoxicity (to pathogens and/or tumors). Species of Phyllomedusa secrete dermaseptins (DSs). The aim of this study was to assess the in vitro cytotoxicity of free and small unilamellar vesicle (SUV)-encapsulated dermaseptin 01 (DS 01) in various human tumor cells. Liposomes were prepared by lipid film hydration followed by sonication. Neutral and cationic, conventional and stealth liposomes were produced. Cytotoxicity was analyzed in lung (NCI-H292), colon (HT-29) and larynx (HEp-2) cancer cells, by the tetrazolium reduction method (MTT) carried out in 96-well microplates. Liposomes were tested for accelerated and long-term stability. In NCI-H292, free DS 01 showed a medium cytostatic effect of 36.5%. The conventional neutral liposome encapsulation of peptide increased this effect, whereas the stealth did not. In HT-29 and HEp-2, free DS 01 inhibited the cell growth by approximately 50% on average. The cationic liposome encapsulation was synergic, inhibition being about 80% in conventional and higher than 95% in stealth liposomes for both celllines. Thus, DS 01, an antimicrobial cationic peptide, showed in vitro cytotoxicity to human tumor cells that was potentiated by nanoencapsulation...


Subject(s)
Antineoplastic Agents/toxicity , In Vitro Techniques
5.
Arq. bras. med. vet. zootec ; 64(2): 419-426, abr. 2012. graf, tab
Article in Portuguese | LILACS | ID: lil-622496

ABSTRACT

Estimou-se o coeficiente de endogamia e avaliou-se seu efeito sobre características morfométricas dos animais em um criatório no norte de Minas Gerais. As características estudadas foram alturas da cernelha e da garupa, comprimentos da cabeça, do pescoço, do dorso-lombo, da garupa e do corpo, larguras do peito e da garupa. O arquivo continha 2186 informações de parentesco de animais do arquivo zootécnico da fazenda, desde o início da formação da raça, 1951, até o ano de 2006. Calculou-se o coeficiente de endogamia (F) e avaliou-se seu efeito por meio de regressão linear simples sobre as medidas morfométricas. Do total de animais, 27,6% mostraram-se endogâmicos, sendo o F médio da população igual a 1,4%. Considerando-se apenas os animais endogâmicos, a consanguinidade média atingiu 5,3%, mínimo de 0,1 e máximo de 28,1%. Não se verificaram efeitos negativos da endogamia sobre as características morfométricas, exceto para largura da garupa, em que se observou que para cada 10% de acréscimo de F houve aumento de 0,576cm na largura da garupa. Possivelmente, devido ao baixo valor encontrado, a endogamia não influenciou as demais características avaliadas.


The coefficient of inbreeding was estimate and its effect on linear traits of the Mangalarga Marchador horses reared in a ranch in the North of Minas Gerais was evaluated. The characteristics studied were morphometric traits such as wither and hip height, length of head, neck, back-loin, hip and body, as well as chest and hip width. The archive had 2186 data on the genealogy of animals from the herd register of the Catuni Farm. The coefficient of inbreeding (F) was calculated and its effect was evaluated by means of simple linear regression on the linear traits. Of all animals, 27.6% showed inbreeding, with an F average of 1.4% in the population. Considering only the inbred animals, the average consanguinity reached 5.3% minimum of 0.1 and maximum of 28.1%. Negative effects of inbreeding on the morphometric traits were not seen, except for hip width, where for each 10% increase in F there was increase of 0.576cm. Possibly due to the low value found, inbreeding did not influence the other evaluated characteristics.

6.
Braz. j. med. biol. res ; 37(10): 1491-1496, Oct. 2004. tab
Article in English | LILACS | ID: lil-383028

ABSTRACT

The aim of the present study was to investigate the effects of daily intragastric administration of bullfrog oil (oleic, linoleic and palmitoleic acid-rich oil), corresponding to 0.4 percent of body weight for four weeks, on fatty acid composition and oxidative stress (lipid peroxidation and catalase activity) in mouse liver. The activities of aspartate aminotransferase (AST), alkaline phosphatase (ALP), alanine aminotransferase (ALT), and gamma-glutamyltransferase (GGT), biomarkers of tissue injury, were determined in liver homogenates and serum. The proportions of 18:2n-6, 20:4n-6, 20:5n-3, and 22:6n-3 (polyunsaturated fatty acids, from 37 to 60 percent) in the total fatty acid content were increased in the liver of the bullfrog oil-treated group (P < 0.05) compared to control. At the same time, a significant decrease in the relative abundance of 14:0, 16:0, and 18:0 (saturated fatty acids, from 49 to 25 percent) was observed. The hepatic content of thiobarbituric acid reactive substances (TBARS) was increased from 2.3 ± 0.2 to 12.3 ± 0.3 nmol TBA-MDA/mg protein and catalase activity was increased from 840 ± 32 to 1110 ± 45 æmol reduced H2O2 min-1 mg protein-1 in the treated group. Bullfrog oil administration increased AST and ALP activities in the liver (from 234.10 ± 0.12 to 342.84 ± 0.13 and 9.38 ± 0.60 to 20.06 ± 0.27 U/g, respectively) and in serum (from 95.41 ± 6.13 to 120.32 ± 3.15 and 234.75 ± 11.5 to 254.41 ± 2.73 U/l, respectively), suggesting that this treatment induced tissue damage. ALT activity was increased from 287.28 ± 0.29 to 315.98 ± 0.34 U/g in the liver but remained unchanged in serum, whereas the GGT activity was not affected by bullfrog oil treatment. Therefore, despite the interesting modulation of fatty acids by bullfrog oil, a possible therapeutic use requires care since some adverse effects were observed in liver.


Subject(s)
Animals , Male , Mice , Catalase , Dietary Fats, Unsaturated , Fatty Acids , Lipid Peroxidation , Liver , Oxidative Stress , Alkaline Phosphatase , Biomarkers , gamma-Glutamyltransferase , Rana catesbeiana , Thiobarbituric Acid Reactive Substances , Transaminases
7.
Braz. j. med. biol. res ; 34(2): 145-154, Feb. 2001.
Article in English | LILACS | ID: lil-281592

ABSTRACT

This article is a transcription of an electronic symposium sponsored by the Brazilian Society of Neuroscience and Behavior (SBNeC). Invited researchers from the European Union, North America and Brazil discussed two issues on anxiety, namely whether panic is a very intense anxiety or something else, and what aspects of clinical anxiety are reproduced by animal models. Concerning the first issue, most participants agreed that generalized anxiety and panic disorder are different on the basis of clinical manifestations, drug response and animal models. Also, underlying brain structures, neurotransmitter modulation and hormonal changes seem to involve important differences. It is also common knowledge that existing animal models generate different types of fear/anxiety. A challenge for future research is to establish a good correlation between animal models and nosological classification


Subject(s)
Humans , Anxiety , Disease Models, Animal , Panic , Anti-Anxiety Agents/pharmacology , Anxiety/drug therapy , Anxiety/physiopathology , Benzodiazepines/pharmacology , Brain/drug effects , Brain/physiopathology , Computer Communication Networks , Fear/drug effects , Panic/drug effects , Periaqueductal Gray/drug effects , Periaqueductal Gray/physiopathology , Serotonin/pharmacology
8.
Braz. j. med. biol. res ; 27(5): 1237-1241, May 1994.
Article in English | LILACS | ID: lil-319801

ABSTRACT

The present study was designed to evaluate the role of ACTH and/or CRF release and corticosteroid receptors (glucocorticoid and mineralocorticoid) in the anxiolytic effect of corticosterone (CORT). Costicosteroid receptor mediation was evaluated using a dose-response analysis of the effect of CORT and by the action of dexamethasone (DEX), which binds to glucocorticoid receptors but not to mineralocorticoid receptors. DEX administration also permits indirect evaluation of the effect of ACTH/CRF release on the anxiolytic effect of CORT. Male Wistar rats (3 months old) weighing 250-350 g were treated sc with vehicle (N = 38), CORT 1.25 (N = 18), 2.5 (N = 13) and 5.0 (N = 24) mg/kg, or DEX 5.0 (N = 19) and 10.0 (N = 17) mg/kg and tested in the elevated plus-maze 2 h later. The group that received the highest dose of CORT (5.0 mg/kg) showed a significant increase in percent open arm entries (38 +/- 2.6, mean +/- SEM) as well as in percent time spent in open arms (27 +/- 4.0) when compared with the vehicle-treated rats (24.3 +/- 2.8 and 12.4 +/- 1.9, respectively; both P < 0.05). There were no other significant differences among groups in the two parameters tested or in total arm entries. These data corroborate previous findings of the anxiolytic effect of CORT and suggest that inhibition of ACTH/CRF release and corticosteroid receptors do not play a major role in the anxiolytic effect of CORT.


Subject(s)
Animals , Male , Rats , Adrenocorticotropic Hormone , Anxiety , Corticosterone , Corticotropin-Releasing Hormone/physiology , Receptors, Steroid , Adrenocorticotropic Hormone , Exploratory Behavior/drug effects , Corticosterone , Dexamethasone , Corticotropin-Releasing Hormone/antagonists & inhibitors , Rats, Wistar , Receptors, Steroid , Time Factors
9.
Braz. j. med. biol. res ; 22(6): 703-5, June 1989. tab
Article in English | LILACS | ID: lil-75171

ABSTRACT

the anxiolytic effect of carba,zepine was measured in rats placed in an elevated plus-maze. Doses from 5 to 40 mg/Kg, ip, of carbamazepine increased the percentage of open arm entries as well as the percentage of time spent in the two opwn arms of the maze. Both of these measures ar interpreted as indexes of anxiety. The total number of entries in either the open or the two enclosed arms, considered as an index of general activity, was not changed by the drug. Therefore, carbamzepine, carba,azepine caused a selective anxiolytic effect as measured in the elevated plus-maze, which is predictive of clinical efficacy


Subject(s)
Rats , Animals , Male , Anxiety , Carbamazepine/pharmacology , Animal Testing Alternatives
10.
Rev. bras. anestesiol ; 38(5): 295-303, set.-out. 1988. ilus
Article in Portuguese | LILACS | ID: lil-74859

ABSTRACT

A possível variaçäo no aparecimento de convulsäo e a mortalidade pós-ictal pela administraçäo de anestésicos locais tipo amida (lidocaína e bupivacaína) e do pentilenotetrazol em relaçäo a faixa etária foram estudadas em camundongos. Apesar da origem subcortical destas convulsöes, apenas o derivado tetrazólico se mostrou convulsivante efetivo desde o período neonatal. Para os anestésicos locais houve um período de hiporresponsividade no desencadeamento de convulsäo na primeira semana de vida, embora tenha sido registrada alta incidência de mortalidade a bupivacaína, sem o aparecimento prévio de episódio convulsivo. Na época do desmame (3ª semana pós-natal) observou-se a mais alta sensibilidade as amidas anestésicas, provavelmente relacionada com o amadurecimento de núcleos relacionados com este tipo de convulsäo, como a amígdala e substantia nigra, e de sistemas de neurotransmissores facilitadores da convulsäo por anestésicos locais, como o colinérgico e o endorfínico. No grupo "geriátrico" de 365 dias houve um discreto aumento na incidência de convulsäo, mas, em relaçäo a lidocaína, evidencia-se o aumento de mortalidade pós-ictal, em comparaçäo com os animais mais jovens. Estes dados falam a favor do conceito de que a imaturidade ou deterioraçäo de núcleos e sistemas de neuro-transmissores centrais, aliadas a alteraçöes farmacocinéticas relacionadas com a idade, podem desempenhar um papel relevante na severidade da convulsäo induzida por amidas anestésicas locais na mortalidade


Subject(s)
Mice , Animals , Bupivacaine/toxicity , Seizures/chemically induced , Lidocaine/toxicity , Pentylenetetrazole/toxicity
13.
Ciênc. cult. (Säo Paulo) ; 35(8): 1130-3, 1983.
Article in English | LILACS | ID: lil-18817

ABSTRACT

Prejuizo no desempenho de camundongos na esquiva passiva e ativa induzida por baclofen. Camundongos albinos, Webster foram injetados com baclofen, droga que atua interferindo com o sistema do acido gama-aminobutilico, e submetidos a treino de resposta de esquiva ativa de duas ou de esquiva passiva. Observou-se, para os grupos injetados com a droga, um desempenho prejudicado nos dois tipos de esquivas.Esses resultados nao podem ser atribuidos a fenomenos de dissociacao de aprendizagem, uma vez que o esquema de administracao da droga, utilizado no presente experimento, permite afastar essa hipotese. E discutido o possivel papel do acido gama-aminobutirico no fenomeno observado


Subject(s)
Animals , Mice , Avoidance Learning , Baclofen
14.
Rev. paul. med ; 100(2): 21-4, 1982.
Article in Portuguese | LILACS | ID: lil-10934

ABSTRACT

Os autores procederam a uma revidao de literatura acerca dos fenomenos da eritropoese medular em recem-nascidos, normais e cardiopatas cianoticos, emitindo os conceitos oriundos de sua expericencia e tracando um paralelo com a situacao dos individuos que habitam em grandes altitudes


Subject(s)
Infant, Newborn , Infant , Humans , Erythropoiesis , Heart Defects, Congenital , Bone Marrow
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