Affiner votre recherche
Résultats 161-170 de 290
Analysis of the cell cycle of fibroblasts derived from the LEC rat after X-irradiation
2006
Masuda, K.(Nagoya City Univ. (Japan)) | Miyamoto, T. | Cho, A.R. | Agui, T.
The LEC rat is reported to exhibit hypersensitivity to X-irradiation, deficiency in DNA double-strand break repair, and radio-resistant DNA synthesis. This character of the LEC rat has been thought to be due to abnormal G1 arrest in cells after X-irradiation. In this report, we re-investigated the effect of X-irradiation on the cell cycle in primary-cultured fibroblasts. Primary-cultured fibroblasts derived from LEC and BN rats were exposed to 4 Gy of X-ray and their cell cycle analysis was performed with a flow cytometer. Fibroblasts derived from both rats showed normal response of the cell cycle, indicating the arrest at both G1- and G2/M-phase and no difference in the cell cycle population between fibroblasts derived from both rats. In contrast, when the same analysis was performed using the cell line, L7 and W8, which had been established from the lung fibroblasts of LEC and control WKAH rats, respectively, by immortalizing with SV40 T-antigen, L7 cells but not W8 cells showed impaired G1 arrest and abnormal cell cycle. These results suggest that fibroblasts derived from LEC rats possess the normal cell cycle response after X-irradiation, if they are kept naive as not immortalized with SV40 T-antigen.
Afficher plus [+] Moins [-]Alymphoplasia mice are resistant to prion infection via oral route
2006
Horiuchi, M.(Hokkaido Univ., Sapporo (Japan)) | Furuoka, H. | Kitamura, N. | Shinagawa, M.
The major cause of infection in animal prion diseases is thought to be consumption of prion-contaminated stuff. There is evidence that the enteric nerve system (ENS) and gut-associated lymphoid tissues (GATL) are involved in the establishment of prion infection through alimentary tract. To elucidate the initial entry port for prion, we inoculated prion to alymphoplasia (aly) mice showing a deficiency in systemic lymph nodes and Peyer's patches. The aly/aly mice were susceptible to prion infection by intra-cranial inoculation and there were no differences in incubation periods between aly/aly mice and wild-type C57BL/6J mice. Incubation periods in aly/aly mice were about 20 days longer than those in C57BL/6J mice with the intra-peritoneal inoculation. The aly/aly mice were completely resistant to prion infection by per os administration, while C57BL/6J mice were sensitive as they entered the terminal stage of disease around 300 days post inoculation. PrPsup(sc) were detected in the intestine and spleen of C57BL/6J mice inoculated with prion intra-peritoneally or orally; however PrPsup(sc) was not detected in the spleen and intestine of aly/aly mice. Prion infectivity was detected in the intestines and spleens of prion-inoculated C57BL/6J mice, even after the early stages of ex-posure, while no infectivity was detected in these tissues of prion-inoculated aly/aly mice. No apparent differences were observed in the organization of the enteric nerve system between wild-type and aly/aly mice. These results indicate that GALT rather than ENS acts as the primary entry port for prion after oral exposure.
Afficher plus [+] Moins [-]Seroepidemiological survey of morbillivirus infection in Kuril harbor seals (Phoca vitulina stejnegeri) of Hokkaido, Japan
2006
Fujii, K.(Hokkaido Univ., Sapporo (Japan)) | Sato, H. | Kakumoto, C. | Kobayashi, M. | Saito, S. | Kariya, T. | Watanabe, Y. | Sakoda, Y. | Kai, C. | Kida, H. | Suzuki, M.
Serological analysis was performed to detect morbillivirus infection in Kuril harbor seals in Hokkaido, Japan. Serum samples were collected from the seals at Nosappu (231 sera), Akkeshi (16), and Erimo (75) between 1998 and 2005. Antibodies to phocine distemper virus (PDV) were detected by ELISA in seals from Nosappu and Erimo. Antibodies to PDV were found in 56% (5/9) of the sampled seals from Nosappu in 1998, versus only 5% (3/66) for 2003, 1% (1/79) for 2004, and 1% (1/77) for 2005. These suggest epidemic caused by the virus in or before 1998. As antibody-positive seals included juvenile seals in 2003 and 2005, sporadic infections of the virus are thought to have occurred in recent years. In Erimo, antibodies to PDV were found in 50% (14/28) of sampled seals in 2004, versus only 13% (1/8) for 1999, 7% (1/15) for 2003, and 0% (0/24) for 2005. These suggest sporadic infection by the virus before 2003 and the epizootic between after autumn in 2003, when samples of 2003 were collected, and 2004. Since antibodies to canine distemper virus (CDV) were detected in one adult seal from Nosappu in each year from 2003 to 2005, sporadic infections of the virus, were suggested. There were no difference in incidence of seals with antibodies to the viruses between males and females and between juveniles and adults.
Afficher plus [+] Moins [-]Pesticide/herbicide pollutants in the Kafue river [Zambia] and a preliminary investigation into their biological effect through catalase levels in fish
2006
Syakalima, M.(University of Zambia, Lusaka) | Choongo, K. | Mwenechanya, R. | Wepener, V. | Yamasaki, M. | Maede, Y.
The study determined the types of pesticide/herbicide pollutants in water, sediment and fish from the Kafue River. A preliminary investigation of the oxidative stress from these pesticides/herbicides was also assessed by measurement of catalase activity. Water, sediment and fish samples were collected upstream, midstream and downstream the Kafue river in Chingola, Kitwe, Kafue National Park and Kafue Town. Water, sediment and fish muscle were sampled and analysed for pesticides using Gas chromatography. For catalase activity fish liver samples only were examined. The pesticides/herbicides detected in all samples collectively included: Heptachlor, pp'-DDE, Cypermethrin, Chlordane, Toxaphene, Terbufos, Kelthane, Endosulfan, Dieldrin, pp'-DDD, pp'-DDT, Atrazine, Disulfoton, d-trans-Allethrin and Endrin. On the other hand, catalase activity was detected in all fish liver samples from all sites. Its levels increased significantly from Chingola upstream to sites down-stream with highest being in Kafue town. This study therefore, demonstrates that there is widespread contamination of the Kafue River with pesticides/herbicides. It also demonstrates that organochlorides are found throughout the river especially in fish samples. The spectrum of pesticides/herbicides was much wider in fish probably due to bioaccumulation. It was also observed that fish are subjected to oxidative stress as determined by catalase levels. The stress is more pronounced downstream where the catalase levels were significantly higher than Chingola. The observation that more pesticide varieties are also found downstream may suggest a likely causative effect of the pesticides on oxidative stress although this needs further investigation. This study further tentatively highlights the potential dangers of these agro-related substances to dependants of the Kafue River water body and the need to carry out risk assessments and thereafter institute corrective measures to help reduce contamination and adverse effects.
Afficher plus [+] Moins [-]Avaliação da reutilização de implantes auriculares contendo norgestomet associados ao valerato ou ao benzoato de estradiol em vacas nelore inseminadas em tempo fixo | Evaluation of norgestomet auricular implants reused associated to valerate or to estradiol benzoate in fixed time artifical insemination in Nelore cows
2006
Alexandre Barreto Almeida | Claudia Maria Bertan | Luis Augusto Ferreira Rossa | Pércio dos Santos Gaspar | Mario Binelli | Ed Hoffmann Madureira
Em fêmeas bovinas a utilização da técnica de inseminação artificial em tempo fixo (IATF) é possibilitada pelo emprego de fármacos que tem como objetivos sincronizar a emergência das ondas foliculares, os estros e a ovulação. Em rebanhos comerciais, o custo de tais fármacos deve estabelecer uma vantajosa relação com os benefícios. O presente estudo, objetivou comparar as taxas de prenhez em vacas Nelore (Bos taurus indicus) inseminadas em tempo fixo, tratadas com implantes auriculares contendo 3mg de norgestomet (Crestar®), novos (IN) ou utilizados uma vez (IR; reutilizados), associados a administração de norgestomet (NG) e valerato de estradiol (VE) ou progesterona (P4) e benzoato de estradiol (BE). Vacas Nelore PO (n=241), amamentando, com o bezerro ao pé, receberam um dos quatro tratamentos: Crestar®novo durante 10 dias associado a administração de 3mg de NG e 5mg de VE (grupo IN/NG+VE; n=61); Crestar®novo inserido durante 8 dias associado a 50mg de P4 e 2mg de BE (grupo IN/P4+BE; n=61); Crestar®reutilizado inserido durante 10 dias associado a administração de 3mg de NG e 5mg de VE (grupo IR/NG+VE; n=58) ou Crestar®reutilizado inserido durante 8 dias associado a e 50mg de P4 e 2mg de BE (grupo IR/P4+BE; n=61). No dia da remoção dos implantes os animais receberam 7,5mg de Luprostiol e 24 horas após a remoção 1mg de BE. A IATF foi realizada 54 a 56 horas após a retirada dos implantes. Após a IATF, as vacas tiveram os estros observados durante um período de 49 dias e em estro foram reinseminadas 12 horas após a observação. O diagnóstico de gestação foi realizado por ultra-sonografia 35 dias após a IATF e após o final da estação de monta. Foram avaliadas as taxas de prenhez na IATF (TP IATF) e no final da estação de monta (TP EM). Não houve interação entre as características dos implantes (novos e reutilizados) e os tratamentos administrados no dia da inserção do implante (NG+VE e P4+BE). A utilização do CIDR®novo ou reutilizado não teve efeito nas TP IATF (48,3% vs 48,7%) e nas TP EM (85,2 vs 86,5%). Os tratamentos com NG+VE e P4+BE não tiveram efeito nas TP IATF (49,5 vs 47,5%) e TP EM (86,5 vs 85,2%). Houve efeito do número de parições (primíparas e multíparas) nas TP IATF (35% vs. 52,7%; P<0,01) e nas TP EM (71,9% vs. 90,2%; P<0,01). Conclui-se que implantes de norgestomet novos e reutilizados, quando associados ao NG+VE ou P4+BE promovem taxas de prenhez bastante satisfatórias em vacas Nelore e que melhores taxas são obtidas em fêmeas multíparas. | The use of fixed-time artificial insemination (IATF) in cows is possible by the use of drugs that aim at the synchronization of the folicular wave pool, the estrus and ovulation. In trading cattle the costs of these drugs must stablish a profitable relation with the benefits. The present study meant to compare the pregnancy rates in Nelore (Bos taurus indicus) cows inseminated at fixed-time, treated with new (IN) or once used (IR; reused) auricular releasing devices with 3mg of norgestomet (Crestar®), associated with the administration of norgestomet (NG) and estradiol valerate (VE) or progesterone (P4) and estradiol benzoate (BE). Pure breed Nelore cows (n=241), on lactation with calf received one of the four treatments: new Crestar®during 10 days administrated with 3mg of NG and 5 mg of VE (group IN/NG+VE; n=61); new Crestar®inserted during 8 days with 50mg of P4 and 2mg of BE (group IN/P4+BE; n=61); reused Crestar®inserted during 10 days in association with 3 mg of norgestomet and 5 mg of VE (group IR/NG+VE; n=58) or reused Crestar®inserted during 8 days in association with 50mg of P4 and 2mg of BE (group IR/P4+BE; n=61). On the day the releasing devices were removed the animals received 7,5mg of Luprostiol and after 24 hours 1mg of BE. A fixed-time artificial insemination was done 54 to 56 hours after the removal of the releasing devices. Cows detected in estrus after the insemination at fixed-time were observed during a period of 49 days and reinseminated. The pregnancy diagnosis was done by ultrassonography 35 days after the IATF and after the end of the breeding season. The pregnancy rates of IATF (TP IATF) and at the end of the breeding season (TP EM) were estimated. There was no interaction between the characteristics of the (new or reused) releasing devices and the treatment given at the day the releasing devices were inserted (NG+VE e P4+BE). The use of new or used CIDR®had no effect on TP IATF (48,3% vs 48,7%) and on TP EM (85,2% vs 86,5%). The treatments with NG+VE e P4+BE did not have effect on TP IATF (49,5% vs 47,5%) and TP EM (86,5 vs 85,2%). There was a effect on the number of parturition (primipara and multipara) on the TP IATF (35% vs 52,7%; P<0,01) and on TP EM (71,9% vs 90,2%; P<0,01). It can be concluded that the new or once used releasing devices with norgestomet when associated with NG+VE or P4+BE promote highly satisfatory pregnancy rates in Nelore cows, being the better rates obtained in multipara females.
Afficher plus [+] Moins [-]Anatomia ultra-sonográfica dos ligamentos patelares de cavalos adultos | Ultrasonographic anatomy of the patellar ligaments in the adults horses
2006
Edivaldo Aparecido Nunes Martins | Raquel Yvonne Arantes Baccarin
Para descrever a anatomia ultra-sonográfica foram examinados os ligamentos patelares (medial, intermédio e lateral) e as estruturas relacionadas de 20 articulações fêmuro-tibio-patelares de cavalos adultos. Tanto a ecogenicidade como o alinhamento das fibras de colágeno, a espessura, a forma e relação com as estruturas vizinhas foram avaliadas. Os três ligamentos apresentaram ecogenicidade uniforme e paralelismo das fibras colágenas. Em secção longitudinal os ligamentos patelares medial (LPM) e intermédio (LPI) apresentaram maior espessura do segmento distal (p<0,01) quando comparado com o proximal. Comparando-se o mesmo segmento entre os três ligamentos, o LPI apresentou espessura maior (p<0,01) em relação ao LPM e ligamento patelar lateral (LPL). Em secção transversal (cm²) o LPL apresentou a maior área (p <0,01), seguido pelo LPI e LPM. Em secção transversal do segmento médio, o LPM apresentou forma triangular, o LPI em forma triangular ou circular, e o LPL formato achatado. As estruturas adjacentes identificadas durante o exame dos ligamentos foram cristas femorais, cartilagem articular, tecido gorduroso periligamentar, patela e tíbia proximal. | In order to describe the ultrasonographic anatomy of patellar ligaments (medial, middle, lateral) and associated structures, 20 femorotibiopatellar joints of adult horses were investigated. Echogenicity, collagen fibers alignment, size, shape and surrounding structures were evaluated. All ligaments presented uniform echogenicity and collagen fibers parallelism. The longitudinal section of the medial and middle patellar ligaments presented a significant larger thickness (p<0,01) of the distal region when compared to the proximal region. When comparing the same site between the three ligaments, LPI was thicker (p<0,01) than lateral patellar ligament (LPL) and LPM. The LPL transversal section (cm²) presented a significant larger area (p<0,01), followed by the LPI and LPM. The transversal section of the medium region revealed a LPM with triangular shape, triangular or circular LPI, and flattened LPL. The surrounding structures observed during the evaluation were: femoral groove, articular cartilages, periligamentar fat tissue, patella and proximal tibia.
Afficher plus [+] Moins [-]Effects of trimming on dairy cattle hoof weight bearing surfaces and pressure distributions | Efeito do casqueamento na distribuição de pressões e suporte de peso na superfície dos cascos de vacas leiteiras
2006
Victor Carvalho | Irenilza Alencar Nääs | Ray Allen Bucklin | Jan Keith Shearer | Leslie Shearer | Valmir Massafera Jr. | Silvia Regina Lucas de Souza
Claw lameness can be associated to biomechanical factors caused by unbalanced pressure distribution under the hooves when cows are confined in modern dairy operations with hard concrete flooring. In the present study, an original claw subdivision4 was slightly modified to differentiate between the anterior (typical sole lesion spot) and posterior portions of the medial sole, and to emphasize the maximum pressures applied only on the area of contact without including the total area within these regions during midstance. The results, obtained showed significance (p < 0.044) for the interaction among Group, Leg and region (G*L*R). It was observed that the rear portion of the claws (heels) on the hind limb of untrimmed cows, are more stressed than the heel region on trimmed cows (23 % versus 16.72% of total pressure applied on the claw for untrimmed and trimmed respectively). The typical sole lesion spot pressures were increased slightly on trimmed cows as compared to untrimmed (20.20% versus 15.9%). The front feet presented differences in pressure concentration on the lateral sole between both groups (29% versus 23.25% for untrimmed versus trimmed respectively). It was concluded that, although the differences were small (5%) changes in pressure concentration, untrimmed cows stress more the sole lateral as compared to trimmed on the front feet, and on the rear feet, they stress more the heel region whereas trimmed cows tend to have a slight better balance among regions. Conversely, when cows are trimmed, the typical sole lesion spot concentrates more pressure than the heel itself (20.20% versus 16.72% respectively) and may favor the occurrence of sole ulcers. | Laminite (manqueira) pode ser associado a fatores mecânicos, causados por falta de balanceamento na distribuição de pressão na sola dos cascos de vacas confinadas em instalações modernas, que utilizam pisos de concreto. No presente estudo, a subdivisão original dos cascos de vacas leiteiras foi modificada para diferenciar-se entre a porção anterior (local típico de lesão) e posterior da sola medial dos cascos, e para enfatizar as pressões máximas aplicadas somente na área de contato não levando em consideração a área total da sola. Os resultados mostraram significância estatística (p < 0.044) para a interação entre Grupo, Pata e Região (G*L*R). Foi observado que a porção posterior (calcanhar) das patas traseiras de vacas não-casqueadas foram estressadas mais intensamente que de vacas casqueadas (23 % versus 16.72% da pressão total aplicada nas patas em não-casqueadas e casqueadas respectivamente). As pressões na região do local típico de lesão aumentaram em animais casqueados comparado com não-casqueados (20.20% versus 15.9%). As patas da frente apresentaram diferenças na concentração de pressão da sola lateral (29% versus 23.25% em não-casqueadas versus casqueadas, respectivamente). Foi concluído que, apesar das diferenças serem pequenas (5%) mudanças nas concentrações de pressão, vacas não-casqueadas estressaram mais a porção da sola lateral, comparado a vacas casqueadas nas patas da frente, enquanto nas traseiras elas estressam mais a região do calcanhar, e as vacas casqueadas tendem a ter uma distribuição melhor de pressão entre as regiões. No entanto, quando as vacas são casqueads, a região típica de lesão tende a concentrar mais pressão do que o próprio calcanhar (20.20% versus 16.72% respectivamente) podendo favorecer a incidência de úlcera de sola.
Afficher plus [+] Moins [-]Morphology and chromatin condensation evaluation in fowl spermatozoa (Gallus gallus, Linnaeus, 1758) through the transmission electron microscopy | Avaliação da morfologia e da compactação cromatínica em espermatozóides de galo (Gallus gallus, Linnaeus, 1758) através de microscopia eletrônica de transmissão
2006
Jaqueline Melo Soares | Marcelo Emílio Beletti
The spermiogram is one of the principal methods of evaluation of the fertility in mammals; however some semen modifications as the spermatozoa chromatin condensation, are not identified in this routine, and can expressively interfere in the fertility of reproducers. In poultry breeding, generally the evaluation of reproducers is made by sampling and the evaluated parameters are in fewer quantities than in mammals, considering the spermatozoa chromatin condensation of the fowl has never been exploited. The objective of this work is verifying through the transmission electron microscopy, whether there are different intensities of spermatozoa chromatin condensation of fowl. So that, have been collected 20 samples of fowl semen, which were placed in 4% glutaraldehyde buffered in 0.1M sodium cacodilate to pH 7.2 for 48 hours, after being centrifugated and rinsed in cacodilate tampon, the semen was post-fixed in 1% osmium tetroxide plus 1.25% potassium ferrocyanide. The sediment was embedded, cut and contrasted. The thin sections were examined and documented in transmission electronic microscopy Zeiss EM-109. Generally the fowl spermatozoon has acrosome with homogenic or slightly granular and of moderate density material, the nucleus with dense or slightly granular chromatin, varies the gray scales, that is, the grades of condensation. It was also observed the "perforatorium", structure that links the nucleus to the acrosome. The insertion of the tail is made through two cetriules, being one transversal and the other longitudinal to the axle. The intermediate piece has typical axoneme involved by mitochondrias, apparently displayed longitudinally. The transition between the principal and the intermediate pieces of the tail is marked by the absence of the mitochondrias. The principal piece is formed by axoneme involved by a granular cytoplasm layer. In the evaluation of the morphological pathologies, it was observed rounded heads, folded, involved by the intermediate container of the piece, in a hook and all of them showing different grades of condensation. | O espermograma é um dos principais métodos de avaliação da fertilidade em mamíferos, contudo, algumas alterações do sêmen como a compactação da cromatina dos espermatozóides, não são identificadas nessa rotina, podendo interferir significativamente na fertilidade de reprodutores. Na avicultura, geralmente a avaliação de reprodutores é feita por amostragem e os parâmetros avaliados são em menor número que em mamíferos, sendo que a compactação da cromatina dos espermatozóides de galo nunca foi explorada. Este trabalho teve como objetivo verificar através da microscopia eletrônica de transmissão, se existe diferentes intensidades de compactação de cromatina em espermatozóides de galo. Para isto, foram coletadas 20 amostras de sêmen de galo, que foram fixadas por 48 horas em glutaraldeído 4% tamponado em cacodilato de sódio 0,1M a pH 7,2, após centrifugado e lavado em tampão cacodilato o sêmen foi pós-fixados em tetróxido de ósmio a 1% mais ferrocianeto de potássio a 1,25%. O sedimento foi incluído, cortado e posteriormente contrastado. Os cortes foram examinados e documentados em microscópio eletrônico Zeiss EM-109. Geralmente, os espermatozóides de galo possuem acrossoma com material homogêneo ou levemente granular e de densidade moderada, o núcleo com cromatina densa e levemente granular, varia as tonalidades de cinza, ou seja, os graus de compactação. Observou-se também o "perforatorium", estrutura que une o núcleo ao acrossoma. A inserção da cauda é por meio de dois centríolos, sendo um transversal e o outro longitudinal ao eixo. A peça intermediária possui axonema típico envolto por mitocôndrias aparentemente dispostas longitudinalmente. A transição entre as peças intermediária e principal da cauda é marcada pela ausência das mitocôndrias. A peça principal é formada pelo axonema envolto por uma camada de citoplasma granular. Na avaliação das patologias morfológicas observaram-se cabeças arredondadas, dobradas, envoltas por conteúdo da peça intermediária, em anzol e todas apresentando diferentes graus de compactação.
Afficher plus [+] Moins [-]Origem e ramificação do tronco braquiocefálico e artéria subclávia em gansos domésticos (Anser domestica) | Origin and ramification of the brachiocephalic trunk and subclavian artery in domestic goose (Anser domestica)
2006
Tatiana Carlesso dos Santos | Cheston Cesar Honorato Pereira | Pedro Primo Bombonato | Luiz Paulo Cobra Monteiro-Filho
Estudou-se, mediante dissecação, a origem e a ramificação dos ramos do tronco braquiocefálico em 30 gansos adultos (Anser domestica), 21 machos e 09 fêmeas. Os animais, após eutanásia, foram injetados, na artéria isquiática direita, com solução de neoprene látex corado e fixados em solução aquosa de formalina 10%. Os troncos braquiocefálicos, direito e esquerdo, originam-se na aorta, logo após a emergência desta, no átrio esquerdo e, dividem-se nas artérias subclávia e carótida comum homônimas. As artérias subclávias emitiram em todos os espécimes, em ambos os antímeros, as artérias esternoclaviculares, axilares e torácicas internas e os troncos peitorais e de forma inconstante as artérias esternoclaviculares acessórias e os ramos pericárdicos. As artérias esternoclaviculares surgiram no antímero direito em 27 (90,0% ± 6,0) e no antímero esquerdo em 25 animais (83,3% ± 7,5). Encontrou-se ramos pericárdicos em 7 animais (23,3% ± 8,5) no antímero direito, em 11 animais (36,7% ± 9,6) no antímero esquerdo e em 4 animais (13,3% ± 6,8) em ambos os antímeros. O tronco peitoral era o ramo terminal da artéria subclávia e dividiu-se nas artérias peitorais cranial e caudal. Não se observou diferenças significativas entre machos e fêmeas quando ao padrão vascular dos dados analisados. | It was studied the origin and the ramification of the branches from brachiocephalic trunk in 30 goose (Anser domestica), adults 21 males and 09 females. The animals, after sacrifice, were injected in the squiatic artery with latex Neoprene solution and fixed in formalin 10% aqueous solution. The brachiocephalic trunks, right and left, arise from aorta, after its emergency in left atria and divided in right and left subclavian and common carotid arteries. The subclavian arteries originated constantly, in both antimeres, the sternoclavicularis, axilar and internal thoracic arteries and the pectoral trunks and inconstantly the accessory esternoclavicularis artery and the pericardium branches. The sternoclavicularis artery arises in the right antimere in 27 (90,0% ± 6,0) and in the left antimere in 25 animals (83,3% ± 7,5). There were the pericardium branches in 7 animals (23,3% ± 8,5) in right antimere, in 11 animals (36,7% ± 9,6) in left antimere and in 4 animals (13,3% ± 6,8) in both sides. The pectoral trunk is a terminal branch from subclavian artery and divided in cranial and caudal pectoral arteries. It weren't observed significant differences between males and females in vascular pattern of the data analyzed.
Afficher plus [+] Moins [-]Avaliação de bioensaios para a determinação da atividade biológica da gonadotrofina coriônica humana (hCG) | Evaluation of bioassays for measuring the of biological activity of Human Chorionic Gonadotropin (hCG)
2006
Claudia Maria Bertan | Pauline Martins da Cunha | Mario Binelli | José Antonio Visintin | Mayra Elena Ortiz D'Avila Assumpção | Rubens Paes de Arruda
A atividade biológica de um hormônio é mensurada pela sua capacidade em exercer um determinado efeito biológico que possa ser quantificado. Os ensaios biológicos in vivo que avaliam a atividade do hCG baseiam-se na sua capacidade de promover um aumento de peso do sistema genital, vesículas seminais e próstata em ratos impúberes e útero e ovários em camundongas impúberes. A partir destes efeitos, determinam-se equações relacionando as doses de hCG administradas com o aumento de peso do sistema genital. O objetivo do presente estudo foi avaliar a eficiência de bioensaios em mensurarem a atividade biológica do hCG utilizando ratos, ratas e camundongas impúberes. No experimento 1, ratos receberam 0, 4, 8 ou 16UI de hCG, a cada 24 horas, durante 4 dias. A próstata e/ou as vesículas seminais foram pesadas 24 horas após a última injeção. No experimento 2, camundongas receberam 0, 3,33, 10, 33,3 ou 100UI de hCG, em um único dia. Os ovários e/ou útero foram pesados 24 horas após a última injeção. O hCG promoveu aumento de peso do sistema genital de camundongas, entretanto, não houve associação linear ou quadrática significativa entre as doses de hCG utilizadas e os pesos das variáveis medidas, impossibilitando a determinação de equações confiáveis. Os protocolos testados, com as doses de hCG utilizadas demonstraram eficiência e sensibilidade limitadas para a quantificação da atividade biológica do hCG. | Biological activity of a given hormone is measured by its capacity to exert a specific, quantifiable biological effect. Aim of biological assays that measure activity of hCG is to construct prediction equations that associate increasing doses of hCG with changes in weights of genitalia, seminal vesicles and prostate gland in pre-pubertal male rats and weights of uterus and ovaries in pre-pubertal female mice. Objective of the present study was to evaluate efficiency of bioassays which used pre-pubertal male rats and female rats and mice to measure hCG activity. In experiment 1, male rats received 0, 4, 8 or 16IU of hCG daily, for 4 days. Prostate and seminal vesicles were weighed 24 hours after last injection. In experiment 2, female mice received 0, 3.33, 10, 33.33 or 100IU of hCG in one day. Ovaries and uteri were weighed 24 hours after the last injection. The hCG increased weights of genitalia in female mice. However, there were no satisfactory linear or quadratic associations between doses of hCG used and variables measured. It was concluded that assays tested showed only limited efficiency and sensibility to quantify hCG biological activity.
Afficher plus [+] Moins [-]