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1.
Braz. j. biol ; 83: e246780, 2023. tab, graf
Artigo em Inglês | LILACS-Express | MEDLINE, LILACSEXPRESS | ID: biblio-1285620

RESUMO

Abstract Anthelmintic drugs have been used strategically in livestock reared in the tropics. These drugs have been used in the treatment of endoparasitism which have resulted in an increase in the animals' performance. The agouti (Dasyprocta leporina) is a neo-tropical rodent with the potential for domestication and has been farmed intensively in Trinidad. However, the objective of this research was to investigate the effect of anthelmintic use of the growth performance of the agouti. In searching the literature, it was found that this type of study on the agouti has not been done. In this experiment fourteen weaned agoutis weighing 1kg were divided into two groups randomly. The first group (T1) was not given any anthelmintic treatment but the second group (T2) was treated with Endovet Ces® subcutaneously every three months. There were no significant differences (p > 0.05) between the two groups in the carcass weight, weight gain, dressing percentage (hot and cold), heart, lungs, skin, head and feet. However, a significant difference (p < 0.05) was seen between groups in the weight of liver and pluck. To the authors knowledge this is the first time that carcass parameters has been presented in literature. The live weight of the animals at the end of the experiment ranged from 2.4 kg to 2.6 kg and animals had a dressing percentage of 57% to 55%. The results are suggestive that the use of anthelmintic drugs in agoutis reared intensively had no significant effect on weight gain and dressing percentage.


Resumo Drogas anti-helmínticas têm sido usadas estrategicamente em rebanhos criados nos trópicos. Essas drogas têm sido utilizadas no tratamento do endoparasitismo, o que resultou em um aumento no desempenho dos animais. A cutia (Dasyprocta leporina) é um roedor neotropical com potencial para domesticação e tem sido criada intensivamente em Trinidad. Porém, o objetivo desta pesquisa foi investigar o efeito do uso de anti-helmínticos no desempenho de crescimento da cutia. Através de uma busca na literatura, constatou-se que esse tipo de estudo na cutia não foi realizado. Neste experimento, quatorze cutias desmamadas pesando 1kg foram divididas em dois grupos aleatoriamente. O primeiro grupo (T1) não recebeu nenhum tratamento anti-helmíntico, mas o segundo grupo (T2) foi tratado com Endovet Ces® por via subcutânea a cada três meses. Não houve diferenças significativas (p> 0,05) entre os dois grupos no peso da carcaça, ganho de peso, porcentagem de cobertura (quente e frio), coração, pulmão, pele, cabeça e pés. No entanto, uma diferença significativa (p <0,05) foi observada entre os grupos no peso do fígado e depenagem. Para os autores, esta é a primeira vez que parâmetros de carcaça são apresentados na literatura. O peso vivo dos animais ao final do experimento variou de 2,4 kg a 2,6 kg e os animais tinham uma porcentagem de curativo de 57% a 55%. Os resultados sugerem que o uso de anti-helmínticos em cutias criadas intensivamente não teve efeito significativo no ganho de peso e na porcentagem de curativo.

2.
Braz. j. biol ; 83: e248493, 2023.
Artigo em Inglês | LILACS-Express | MEDLINE, LILACSEXPRESS | ID: biblio-1339399

RESUMO

Abstract Parasites of veterinary importance have been heavily focused on domesticated livestock that was introduced into the neo-tropics. The text used in the teaching parasitology to veterinary students in Trinidad has only investigated the parasites of domesticated species. In the reviewed veterinary parasitology text no mention was made on the parasites that affect wild neo-tropical animals. Information on wild neo-tropical animals had to be sourced from texts on the management of wild life animals in the Neotropics. The texts that were reviewed in this document spanned from the mid-1950s to 2020. The information presented in this review reveals the exhaustive work done on the parasites of domesticated species but also revealed little information on neo-tropical animals with the potential for domestication. In conclusion, this review reveals the gap of information that is missing from parasitology texts used in the teaching of veterinary students. In the future these parasitology texts can be revised to include chapters on the parasites of neo-tropical animals with the potential for domestication. At present students that graduate from the veterinary parasitology course has little information on the parasites of animals which are present in their 'backyards'.


Resumo Parasitas de importância veterinária têm se concentrado fortemente em animais domésticos que foram introduzidos na região neotrópica. O texto usado no ensino de parasitologia para estudantes de veterinária em Trinidad investigou apenas os parasitas de espécies domesticadas. No texto de parasitologia veterinária revisado, nenhuma menção foi feita sobre os parasitas que afetam os animais selvagens neotropicais. As informações sobre animais selvagens neotropicais tiveram que ser obtidas a partir de textos sobre o manejo de animais selvagens nos Neotrópicos. Os textos revisados neste documento vão de meados da década de 1950 até 2020. As informações apresentadas nesta revisão revelam o trabalho exaustivo realizado sobre os parasitas de espécies domesticadas, mas também revelaram poucas informações sobre animais neotropicais com potencial para domesticação. Em conclusão, esta revisão revela a lacuna de informação que existe nos textos de parasitologia utilizados no ensino de estudantes de veterinária. No futuro, esses textos de parasitologia podem ser revisados ​​para incluir capítulos sobre os parasitas de animais neotropicais com potencial para domesticação. Atualmente, os alunos que se formam no curso de parasitologia veterinária têm poucas informações sobre os parasitas de animais que estão presentes em seus "quintais".

3.
Braz. j. biol ; 82: e237869, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1249268

RESUMO

Abstract Reproductive diseases have been well documented in domestic livestock such as sheep, goat, cattle and pigs. However, there is very little information on these diseases in the agouti (Dasyprocta leporina). The agouti is used for its meat in South America and the Caribbean. More recently, intensive farming of this animal is being practiced in the Neotropics. There is dearth of information on dystocia and vaginal prolapses in the agouti. This document reports on three cases of reproductive diseases in captive reared agoutis in Trinidad and Tobago. The first case was a female agouti weighing approximately 3 kg that was in the last stage of pregnancy, which was found dead in its cage. The vulva of the mother had the protruding hind-limbs of the fetus. Necroscopic evaluation of carcass revealed little fat tissue and the mother had two fetuses in the right horn of the uterus. Each fetus weighed approximately 200 g. The fetuses were well formed with fur, teeth and eyes. The placenta was attached to each fetus. The pathological findings suggested that dystocia resulted from secondary uterine inertia which was the cause of death of the adult female agouti. The second case was that of an adult female agouti weighing 2.5 kg. This female had given birth to an offspring three weeks prior and was observed to have had a vaginal prolapse. Surgery was performed and the prolapsed vagina was placed back into the pelvic cavity. Further to this intervention, the vagina prolapsed twice. Subsequent to the re-insertion of the vaginal tissue the agouti was euthanized. The third case was also that of a dystocia. However, the fetuses weighed 235 g and 165 g respectively and were in normal presentation, posture and positioning. The fetus however was unable to pass via the vagina and was trapped in the pelvic cavity. This caused secondary uterine inertia which was the cause of death. The causes of reproductive diseases in these cases are unknown but the feeding management and space allowance given to the agouti in late gestation may be contributing factors.


Resumo As doenças reprodutivas têm sido bem documentadas em rebanhos domésticos, como ovinos, caprinos, bovinos e suínos. Porém, há muito pouca informação sobre essas doenças na cutia (Dasyprocta leporina). A cutia é usada como carne na América do Sul e no Caribe. Mais recentemente, a criação intensiva desse animal está sendo praticada na região neotropical., Há escassez de informações sobre distocia e prolapsos vaginais na cutia. Este documento relata três casos de doenças reprodutivas em cutias criadas em cativeiro em Trinidad e Tobago. O primeiro caso foi de uma cutia de aproximadamente 3 kg que estava na última fase de gestação, encontrada morta em sua gaiola. A vulva da mãe tinha as patas traseiras salientes do feto. A avaliação necroscópica da carcaça revelou pouco tecido adiposo e a mãe tinha dois fetos no corno direito do útero. Cada feto pesava aproximadamente 200 g. Os fetos eram bem formados com pelos, dentes e olhos. A placenta foi presa a cada feto. Os achados patológicos sugeriram que a distocia resultou de inércia uterina secundária, que foi a causa da morte da cutia adulta. O segundo caso foi o de uma cutia adulta pesando 2,5 kg. Essa fêmea deu à luz uma cria três semanas antes e foi observado que tinha prolapso vaginal., A cirurgia foi realizada e a vagina prolapsada foi colocada de volta na cavidade pélvica. Após essa intervenção, a vagina prolapsou duas vezes. Após a reinserção do tecido vaginal, a cutia foi eutanasiada. O terceiro caso também foi de distocia. No entanto, os fetos pesavam 235 g e 165 g e estavam em apresentação, postura e posicionamento normais. O feto, entretanto, não conseguiu passar pela vagina e ficou preso na cavidade pélvica. Isso causou inércia uterina secundária, que foi a causa da morte. As causas das doenças reprodutivas nesses casos são desconhecidas, mas o manejo da alimentação e o espaço concedido à cutia no final da gestação podem ser fatores contribuintes.

4.
Braz J Biol ; 83: e248493, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495164

RESUMO

Parasites of veterinary importance have been heavily focused on domesticated livestock that was introduced into the neo-tropics. The text used in the teaching parasitology to veterinary students in Trinidad has only investigated the parasites of domesticated species. In the reviewed veterinary parasitology text no mention was made on the parasites that affect wild neo-tropical animals. Information on wild neo-tropical animals had to be sourced from texts on the management of wild life animals in the Neotropics. The texts that were reviewed in this document spanned from the mid-1950s to 2020. The information presented in this review reveals the exhaustive work done on the parasites of domesticated species but also revealed little information on neo-tropical animals with the potential for domestication. In conclusion, this review reveals the gap of information that is missing from parasitology texts used in the teaching of veterinary students. In the future these parasitology texts can be revised to include chapters on the parasites of neo-tropical animals with the potential for domestication. At present students that graduate from the veterinary parasitology course has little information on the parasites of animals which are present in their 'backyards'.


Assuntos
Animais Selvagens , Educação em Veterinária , Animais , Humanos , Faculdades de Medicina Veterinária , Estudantes , Trinidad e Tobago , Universidades
5.
Braz J Biol ; 83: e246780, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34378684

RESUMO

Anthelmintic drugs have been used strategically in livestock reared in the tropics. These drugs have been used in the treatment of endoparasitism which have resulted in an increase in the animals' performance. The agouti (Dasyprocta leporina) is a neo-tropical rodent with the potential for domestication and has been farmed intensively in Trinidad. However, the objective of this research was to investigate the effect of anthelmintic use of the growth performance of the agouti. In searching the literature, it was found that this type of study on the agouti has not been done. In this experiment fourteen weaned agoutis weighing 1kg were divided into two groups randomly. The first group (T1) was not given any anthelmintic treatment but the second group (T2) was treated with Endovet Ces® subcutaneously every three months. There were no significant differences (p > 0.05) between the two groups in the carcass weight, weight gain, dressing percentage (hot and cold), heart, lungs, skin, head and feet. However, a significant difference (p < 0.05) was seen between groups in the weight of liver and pluck. To the authors knowledge this is the first time that carcass parameters has been presented in literature. The live weight of the animals at the end of the experiment ranged from 2.4 kg to 2.6 kg and animals had a dressing percentage of 57% to 55%. The results are suggestive that the use of anthelmintic drugs in agoutis reared intensively had no significant effect on weight gain and dressing percentage.


Assuntos
Anti-Helmínticos , Cuniculidae , Dasyproctidae , Animais , Roedores , Trinidad e Tobago
6.
Braz J Biol ; 82: e237869, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34105674

RESUMO

Reproductive diseases have been well documented in domestic livestock such as sheep, goat, cattle and pigs. However, there is very little information on these diseases in the agouti (Dasyprocta leporina). The agouti is used for its meat in South America and the Caribbean. More recently, intensive farming of this animal is being practiced in the Neotropics. There is dearth of information on dystocia and vaginal prolapses in the agouti. This document reports on three cases of reproductive diseases in captive reared agoutis in Trinidad and Tobago. The first case was a female agouti weighing approximately 3 kg that was in the last stage of pregnancy, which was found dead in its cage. The vulva of the mother had the protruding hind-limbs of the fetus. Necroscopic evaluation of carcass revealed little fat tissue and the mother had two fetuses in the right horn of the uterus. Each fetus weighed approximately 200 g. The fetuses were well formed with fur, teeth and eyes. The placenta was attached to each fetus. The pathological findings suggested that dystocia resulted from secondary uterine inertia which was the cause of death of the adult female agouti. The second case was that of an adult female agouti weighing 2.5 kg. This female had given birth to an offspring three weeks prior and was observed to have had a vaginal prolapse. Surgery was performed and the prolapsed vagina was placed back into the pelvic cavity. Further to this intervention, the vagina prolapsed twice. Subsequent to the re-insertion of the vaginal tissue the agouti was euthanized. The third case was also that of a dystocia. However, the fetuses weighed 235 g and 165 g respectively and were in normal presentation, posture and positioning. The fetus however was unable to pass via the vagina and was trapped in the pelvic cavity. This caused secondary uterine inertia which was the cause of death. The causes of reproductive diseases in these cases are unknown but the feeding management and space allowance given to the agouti in late gestation may be contributing factors.


Assuntos
Dasyproctidae , Animais , Região do Caribe , Bovinos , Feminino , Gravidez , Ovinos , América do Sul , Suínos , Trinidad e Tobago
8.
Nat Commun ; 11(1): 5978, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33293507

RESUMO

Many global environmental agendas, including halting biodiversity loss, reversing land degradation, and limiting climate change, depend upon retaining forests with high ecological integrity, yet the scale and degree of forest modification remain poorly quantified and mapped. By integrating data on observed and inferred human pressures and an index of lost connectivity, we generate a globally consistent, continuous index of forest condition as determined by the degree of anthropogenic modification. Globally, only 17.4 million km2 of forest (40.5%) has high landscape-level integrity (mostly found in Canada, Russia, the Amazon, Central Africa, and New Guinea) and only 27% of this area is found in nationally designated protected areas. Of the forest inside protected areas, only 56% has high landscape-level integrity. Ambitious policies that prioritize the retention of forest integrity, especially in the most intact areas, are now urgently needed alongside current efforts aimed at halting deforestation and restoring the integrity of forests globally.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/estatística & dados numéricos , Política Ambiental , Florestas , África Central , Canadá , Mudança Climática , Conservação dos Recursos Naturais/legislação & jurisprudência , Nova Guiné , Federação Russa
9.
Sci Adv ; 5(4): eaau7668, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30949575

RESUMO

The river Nile flows across 11 African countries, supporting millions of human livelihoods, and holding globally important biodiversity and endemism yet remains underprotected. No basin-wide spatial conservation planning has been attempted to date, and the importance of coordinated conservation planning for the Nile's biodiversity remains unknown. We address these gaps by creating a basin-wide conservation plan for the Nile's freshwater fish. We identify priority areas for conservation action and compare cross-boundary collaboration scenarios for achieving biodiversity conservation targets, accounting for river connectivity. We found that collaborative conservation efforts are crucial for reducing conservation costs, saving 34% of costs compared to an uncoordinated, business-as-usual scenario. While most Nile basin countries benefit from coordinating conservation planning, costs and benefits are unequally distributed. We identify "hot spots" consistently selected as conservation priority areas across all collaboration scenarios, and provide a framework for improving return on conservation investment for large and complex river systems globally.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Rios , África , Geografia , Humanos
10.
Neurobiol Dis ; 111: 102-117, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29274742

RESUMO

We evaluated the impact of early embryonic deletion of huntingtin (htt) from pyramidal neurons on cortical development, cortical neuron survival and motor behavior, using a cre-loxP strategy to inactivate the mouse htt gene (Hdh) in emx1-expressing cell lineages. Western blot confirmed substantial htt reduction in cerebral cortex of these Emx-httKO mice, with residual cortical htt in all likelihood restricted to cortical interneurons of the subpallial lineage and/or vascular endothelial cells. Despite the loss of htt early in development, cortical lamination was normal, as revealed by layer-specific markers. Cortical volume and neuron abundance were, however, significantly less than normal, and cortical neurons showed reduced brain-derived neurotrophic factor (BDNF) expression and reduced activation of BDNF signaling pathways. Nonetheless, cortical volume and neuron abundance did not show progressive age-related decline in Emx-httKO mice out to 24months. Although striatal neurochemistry was normal, reductions in striatal volume and neuron abundance were seen in Emx-httKO mice, which were again not progressive. Weight maintenance was normal in Emx-httKO mice, but a slight rotarod deficit and persistent hyperactivity were observed throughout the lifespan. Our results show that embryonic deletion of htt from developing pallium does not substantially alter migration of cortical neurons to their correct laminar destinations, but does yield reduced cortical and striatal size and neuron numbers. The Emx-httKO mice were persistently hyperactive, possibly due to defects in corticostriatal development. Importantly, deletion of htt from cortical pyramidal neurons did not yield age-related progressive cortical or striatal pathology.


Assuntos
Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/metabolismo , Corpo Estriado/crescimento & desenvolvimento , Corpo Estriado/metabolismo , Proteína Huntingtina/deficiência , Células Piramidais/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Contagem de Células , Sobrevivência Celular/fisiologia , Córtex Cerebral/patologia , Corpo Estriado/patologia , Feminino , Proteína Huntingtina/genética , Masculino , Camundongos Knockout , Atividade Motora/fisiologia , Células Piramidais/patologia
11.
Neuroscience ; 229: 176-99, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23069761

RESUMO

Global-heterozygous and brain-specific homozygous knockouts (KOs) of brain-derived neurotrophic factor (BDNF) cause late- and early-onset obesity, respectively, both involving hyperphagia. Little is known about the mechanism underlying this hyperphagia or whether BDNF loss from peripheral tissues could contribute to overeating. Since global-homozygous BDNF-KO is perinatal lethal, a BDNF-KO that spared sufficient brainstem BDNF to support normal health was utilized to begin to address these issues. Meal pattern and microstructure analyses suggested overeating of BDNF-KO mice was mediated by deficits in both satiation and satiety that resulted in increased meal size and frequency and implicated a reduction of vagal signaling from the gut to the brain. Meal-induced c-Fos activation in the nucleus of the solitary tract, a more direct measure of vagal afferent signaling, however, was not decreased in BDNF-KO mice, and thus was not consistent with a vagal afferent role. Interestingly though, meal-induced c-Fos activation was increased in the dorsal motor nucleus of the vagus nerve (DMV) of BDNF-KO mice. This could imply that augmentation of vago-vagal digestive reflexes occurred (e.g., accommodation), which would support increased meal size and possibly increased meal number by reducing the increase in intragastric pressure produced by a given amount of ingesta. Additionally, vagal sensory neuron number in BDNF-KO mice was altered in a manner consistent with the increased meal-induced activation of the DMV. These results suggest reduced BDNF causes satiety and satiation deficits that support hyperphagia, possibly involving augmentation of vago-vagal reflexes mediated by central pathways or vagal afferents regulated by BDNF levels.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hiperfagia/complicações , Obesidade/etiologia , Núcleo Solitário/metabolismo , Animais , Composição Corporal/fisiologia , Peso Corporal/fisiologia , Fator Neurotrófico Derivado do Encéfalo/genética , Ingestão de Alimentos/fisiologia , Hiperfagia/genética , Hiperfagia/metabolismo , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Obesidade/genética , Obesidade/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo
12.
Neuroscience ; 212: 1-18, 2012 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-22542678

RESUMO

Brain-derived neurotrophic factor (BDNF) plays important roles in the development, maintenance, and plasticity of the mammalian forebrain. These functions include regulation of neuronal maturation and survival, axonal and dendritic arborization, synaptic efficacy, and modulation of complex behaviors including depression and spatial learning. Although analysis of mutant mice has helped establish essential developmental functions for BDNF, its requirement in the adult is less well documented. We have studied late-onset forebrain-specific BDNF knockout (CaMK-BDNF(KO)) mice, in which BDNF is lost primarily from the cortex and hippocampus in early adulthood, well after BDNF expression has begun in these structures. We found that although CaMK-BDNF(KO) mice grew at a normal rate and can survive more than a year, they had smaller brains than wild-type siblings. The CaMK-BDNF(KO) mice had generally normal behavior in tests for ataxia and anxiety, but displayed reduced spatial learning ability in the Morris water task and increased depression in the Porsolt swim test. These behavioral deficits were very similar to those we previously described in an early-onset forebrain-specific BDNF knockout. To identify an anatomical correlate of the abnormal behavior, we quantified dendritic spines in cortical neurons. The spine density of CaMK-BDNF(KO) mice was normal at P35, but by P84, there was a 30% reduction in spine density. The strong similarities we find between early- and late-onset BDNF knockouts suggest that BDNF signaling is required continuously in the CNS for the maintenance of some forebrain circuitry also affected by developmental BDNF depletion.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/biossíntese , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/metabolismo , Espinhas Dendríticas/metabolismo , Deficiências do Desenvolvimento/metabolismo , Transtornos Mentais/metabolismo , Animais , Comportamento Animal/fisiologia , Fator Neurotrófico Derivado do Encéfalo/deficiência , Fator Neurotrófico Derivado do Encéfalo/genética , Espinhas Dendríticas/patologia , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/fisiopatologia , Modelos Animais de Doenças , Feminino , Masculino , Transtornos Mentais/genética , Transtornos Mentais/fisiopatologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos
13.
Bull World Health Organ ; 89(3): 221-6, 2011 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21379418

RESUMO

Delivery of vaccine antigens to the dermis and/or epidermis of human skin (i.e. intradermal delivery) might be more efficient than injection into the muscle or subcutaneous tissue, thereby reducing the volumes of antigen. This is known as dose-sparing and has been demonstrated in clinical trials with some, but not all, vaccines. Dose-sparing could be beneficial to immunization programmes by potentially reducing the costs of purchase, distribution and storage of vaccines; increasing vaccine availability and effectiveness. The data obtained with intradermal delivery of some vaccines are encouraging and warrant further study and development; however significant gaps in knowledge and operational challenges such as reformulation, optimizing vaccine presentation and development of novel devices to aid intradermal vaccine delivery need to be addressed. Modelling of the costs and potential savings resulting from intradermal delivery should be done to provide realistic expectations of the potential benefits and to support cases for investment. Implementation and uptake of intradermal vaccine delivery requires further research and development, which depends upon collaboration between multiple stakeholders in the field of vaccination.


Assuntos
Vacinas/administração & dosagem , Ensaios Clínicos como Assunto , Controle de Custos/métodos , Humanos , Injeções Intradérmicas
14.
Int J Radiat Biol ; 81(6): 445-58, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16308915

RESUMO

Ionizing radiation has been reported to promote accelerated or premature senescence in both normal and tumour cell lines. The current studies were designed to characterize the accelerated senescence response to radiation in the breast tumour cell in terms of its dependence on functional p53 and its relationship to telomerase activity, telomere lengths, expression of human telomerase reverse transcriptase (hTERT, the catalytic subunit of telomerase) and human telomerase RNA (hTR, the RNA subunit of telomerase), as well as the induction of cytogenetic aberrations. Studies were performed in p53 wild-type MCF-7 cells, MCF-7/E6 cells with attenuated p53 function, MDA-MB231 cells with mutant p53 and MCF-7/hTERT cells with constitutive expression of hTERT. Telomerase activity was measured by the telomeric repeat amplification protocol (TRAP assay), telomere lengths by the terminal restriction fragment (TRF) assay, hTR and hTERT expression by reverse transcriptase-polymerase chain reaction (RT-PCR), senescence by beta-galactosidase staining, and apoptosis by TdT-mediated d-UTP-X nick-end labelling (TUNEL assay). Widespread and extensive expression of beta-galactosidase, a marker of cellular senescence, was evident in MCF-7 breast tumour cells following exposure to 10 Gy of ionizing radiation. Radiation did not suppress expression of either hTERT or hTR, alter telomerase activity or induce telomere shortening. Senescence arrest was also observed in irradiated MCF-7/hTERT cells, which have elongated telomeres due to the ectopic expression of the catalytic component of telomerase. In contrast to MCF-7 cells, irradiated MDA-MB231 breast tumour cells and MCF-7/E6 cells failed to senesce and instead demonstrated a delayed apoptotic cell death. Irradiation produced chromosome end associated abnormalities, including end-to-end fusions (an indicator of telomere dysfunction) in MCF-7 cells, MCF-7/hTERT cells, as well as in MCF-7/E6 cells. When cells were maintained in culture following irradiation, proliferative recovery was evident exclusively after senescence while the cell lines which responded to radiation by apoptosis continued to decline in cell number. Accelerated senescence in response to ionizing radiation is p53 dependent and associated with telomer dysfunction but is unrelated to changes in telomerase activity or telomere lengths, expression of hTERT and hTR. In the absence of functional p53, cells are unable to arrest for an extended period, resulting in apoptotic cell death while accelerated senescence in cells expressing p53 is succeeded by proliferative recovery.


Assuntos
Neoplasias da Mama/radioterapia , Senescência Celular/efeitos da radiação , Proteína Supressora de Tumor p53/fisiologia , Apoptose/efeitos da radiação , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Aberrações Cromossômicas , Proteínas de Ligação a DNA/metabolismo , Feminino , Humanos , RNA/análise , Telomerase/análise , Telomerase/metabolismo , Telômero
15.
Neuroscience ; 121(2): 341-54, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14521993

RESUMO

Brain-derived neurotrophic factor (BDNF) participates in synaptic plasticity and the adaptive changes in the strength of communication between neurons thought to underlie aspects of behavioral adaptation. By selectively deleting BDNF from the forebrain of mice using the Cre site-specific DNA recombinase, we were able to study the requirements for BDNF in behaviors such as learning and anxiety. Early-onset forebrain-restricted BDNF mutant mice (Emx-BDNF(KO)) that develop in the absence of BDNF in the dorsal cortex, hippocampus, and parts of the ventral cortex and amygdala failed to learn the Morris Water Maze task, a hippocampal-dependent visuo-spatial learning task. Freezing during all phases of cued-contextual fear conditioning, a behavioral task designed to study hippocampal-dependent associative learning, was enhanced. These mice learned a brightness discrimination task well but were impaired in a more difficult pattern discrimination task. Emx-BDNF(KO) mice did not exhibit altered sensory processing and gating, as measured by the acoustic startle response or prepulse inhibition of the startle response. Although they were less active in an open-field arena, they did not show alterations in anxiety, as measured in the elevated-plus maze, black-white chamber or mirrored chamber tasks. Combined, these data indicate that although an absence of forebrain BDNF does not disrupt acoustic sensory processing or alter baseline anxiety, specific forms of learning are severely impaired.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Deficiências da Aprendizagem/fisiopatologia , Prosencéfalo/metabolismo , Estimulação Acústica , Animais , Ansiedade , Comportamento Animal , Fator Neurotrófico Derivado do Encéfalo/deficiência , Fator Neurotrófico Derivado do Encéfalo/genética , Condicionamento Clássico , Aprendizagem por Discriminação , Medo , Genótipo , Proteínas de Homeodomínio/genética , Aprendizagem em Labirinto , Transtornos da Memória , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout/metabolismo , Camundongos Knockout/fisiologia , Atividade Motora , Tempo de Reação , Reflexo de Sobressalto/fisiologia , Fatores de Tempo , Fatores de Transcrição
16.
Surg Endosc ; 16(6): 921-6, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12163955

RESUMO

BACKGROUND: Laparoscopic cholecystectomy is frequently an ambulatory procedure, but some patients are best admitted for a brief hospital stay. In this study, we compared the functional health status, symptoms, and outcomes of patients undergoing ambulatory elective laparoscopic cholecystectomy to those with brief hospital admission. The purpose was to assess patient satisfaction and to identify factors that might assist in selecting patients for ambulatory vs short-stay operations. METHODS: A total of 140 patients scheduled for elective cholecystectomy completed the SF-36 health survey and provided additional information regarding symptoms preoperatively, at 2 months, and at 6 months after operation. RESULTS: All patients had symptomatic gallstones; 76 were admitted to the hospital, and 64 were ambulatory. Admitted patients reported more emotional role limitations on preoperative SF-36. They also reported symptoms of depression more often. Patients in both groups were equally relieved of symptoms of pain, nausea, vomiting, and tenderness. Satisfaction with care was similar for both groups; however, at 2 and 6 months, admitted patients continued to report significantly poorer functional health status than ambulatory patients. CONCLUSION: A reliable, reproducible measure of functional health status, such as the SF-36, may be useful for identifying patients who are appropriate for short-stay hospital admission after laparoscopic cholecystectomy as part of a decision process that tries to optimize outcomes while utilizing resources efficiently.


Assuntos
Assistência Ambulatorial/estatística & dados numéricos , Colecistectomia Laparoscópica/estatística & dados numéricos , Nível de Saúde , Tempo de Internação/estatística & dados numéricos , Efeitos Psicossociais da Doença , Feminino , Seguimentos , Humanos , Masculino , Vigilância da População , Estudos Prospectivos , Reprodutibilidade dos Testes , Distribuição por Sexo , Resultado do Tratamento
17.
Exp Neurol ; 172(1): 81-91, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11681842

RESUMO

During early postnatal development, apoptosis of retinal ganglion cells (RGCs) is regulated by target contact with the optic tectum. The neurotrophins BDNF and NT-4, but not NGF, prevent the apoptosis of retinal ganglion cells that is otherwise observed after target ablation or axotomy. Thus receptors activated by BDNF and NT-4 are candidates to mediate the early postnatal survival of RGCs. BDNF and NT-4, but not NGF, bind to all isoforms of the receptor TrkB, whether or not they contain a tyrosine kinase domain. To examine the roles of TrkB receptor isoforms in early postnatal survival, we compared RGC numbers in wild-type mice to those in a mutant lacking all isoforms of TrkB. Surprisingly, no reduction in RGCs was observed in the mutant at postnatal day 16, the latest age at which these animals are consistently viable, so TrkB signaling is not essential for target-dependent survival of these cells. In wild-type mice, RGCs also are lost gradually during adulthood, possibly due to oxidative stress. To determine whether TrkB signaling regulates this phase of RGC degeneration, RGC numbers were examined in a viable mutant of TrkB that expresses only about 25% the normal level of TrkB receptor kinase. Compared to controls, approximately 20% of the RGC were lost in mutant 3-month-old-animals. Thus, TrkB signaling is not required for survival of RGCs during the period of target-dependent survival, but does appear to reduce degeneration of RGCs in adult animals.


Assuntos
Receptor trkB/metabolismo , Células Ganglionares da Retina/metabolismo , Envelhecimento/metabolismo , Animais , Axônios/ultraestrutura , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Contagem de Células , Sobrevivência Celular/fisiologia , Heterozigoto , Camundongos , Camundongos Knockout , Camundongos Mutantes , Camundongos Transgênicos , Isoformas de Proteínas/deficiência , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptor trkB/deficiência , Receptor trkB/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Retina/citologia , Retina/crescimento & desenvolvimento , Células Ganglionares da Retina/citologia , Transdução de Sinais/fisiologia , Colículos Superiores/citologia , beta-Galactosidase/genética
18.
Gastroenterology ; 121(4): 799-804, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11606493

RESUMO

BACKGROUND & AIMS: Heredity has been suggested to explain the finding that irritable bowel syndrome (IBS) tends to run in families. Research in this area has been limited. The aim of the present study was to assess the relative contribution of genetic and environmental (social learning) influences on the development of IBS by comparing concordance rates in monozygotic and dizygotic twins to concordance between mothers and their children. METHODS: Questionnaires soliciting information on the occurrence of more than 80 health problems, including IBS, in self and other family members were sent to both members of 11,986 twin pairs. RESULTS: Analysis is based on 10,699 respondents representing 6060 twin pairs. Concordance for IBS was significantly greater (P = 0.030) in monozygotic (17.2%) than in dizygotic (8.4%) twins, supporting a genetic contribution to IBS. However, the proportion of dizygotic twins with IBS who have mothers with IBS (15.2%) was greater than the proportion of dizygotic twins with IBS who have co-twins with IBS (6.7%, P < 0.001), and logistic regression analysis showed that having a mother with IBS and having a father with IBS are independent predictors of irritable bowel status (P < 0.001); both are stronger predictors than having a twin with IBS. Addition of information about the other twin accounted for little additional predictive power. CONCLUSIONS: Heredity contributes to development of IBS, but social learning (what an individual learns from those in his or her environment) has an equal or greater influence.


Assuntos
Doenças Funcionais do Colo/etiologia , Doenças Funcionais do Colo/genética , Aprendizagem , Comportamento Social , Gêmeos Dizigóticos , Gêmeos Monozigóticos , Adulto , Doenças Funcionais do Colo/prevenção & controle , Demografia , Meio Ambiente , Feminino , Humanos , Masculino , Análise de Regressão , Reprodutibilidade dos Testes , Virginia
19.
J Neurosci ; 21(16): 6170-80, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11487640

RESUMO

Previous work suggested qualitatively different effects of neurotrophin 3 (NT-3) in cochlear innervation patterning in different null mutants. We now show that all NT-3 null mutants have a similar phenotype and lose all neurons in the basal turn of the cochlea. To understand these longitudinal deficits in neurotrophin mutants, we have compared the development of the deficit in the NT-3 mutant to the spatial-temporal expression patterns of brain-derived neurotrophic factor (BDNF) and NT-3, using lacZ reporters in each gene and with expression of the specific neurotrophin receptors, trkB and trkC. In the NT-3 mutant, almost normal numbers of spiral ganglion neurons form, but fiber outgrowth to the basal turn is eliminated by embryonic day (E) 13.5. Most neurons are lost between E13.5 and E15.5. During the period preceding apoptosis, NT-3 is expressed in supporting cells, whereas BDNF is expressed mainly in hair cells, which become postmitotic in an apical to basal temporal gradient. During the period of neuronal loss, BDNF is absent from the basal cochlea, accounting for the complete loss of basal turn neurons in the NT-3 mutant. The spatial gradients of neuronal loss in these two mutants appear attributable to spatial-temporal gradients of neurotrophin expression. Our immunocytochemical data show equal expression of their receptors, TrkB and TrkC, in spiral sensory neurons and thus do not relate to the basal turn loss. Mice in which NT-3 was replaced by BDNF show a qualitative normal pattern of innervation at E13.5. This suggests that the pattern of expression of neurotrophins rather than their receptors is essential for the spatial loss of spiral sensory neurons in NT-3 null mutants.


Assuntos
Cóclea/inervação , Cóclea/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Neurotrofina 3/biossíntese , Neurotrofina 3/genética , Vias Aferentes/citologia , Vias Aferentes/embriologia , Animais , Animais Recém-Nascidos , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Fator Neurotrófico Derivado do Encéfalo/genética , Contagem de Células , Sobrevivência Celular/genética , Cóclea/embriologia , Genes Reporter , Heterozigoto , Homozigoto , Imuno-Histoquímica , Óperon Lac , Camundongos , Camundongos Mutantes , Mutação , Neurônios Aferentes/citologia , Neurônios Aferentes/metabolismo , Fenótipo , Receptor trkB/biossíntese , Receptor trkC/biossíntese , Gânglio Espiral da Cóclea/citologia , Gânglio Espiral da Cóclea/embriologia
20.
Dis Colon Rectum ; 44(5): 728-36, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11357037

RESUMO

PURPOSE: The aims of this review are 1) to critically evaluate the literature on the efficacy of biofeedback treatment for fecal incontinence, 2) to compare different types of biofeedback, and 3) to identify patient characteristics which predict a successful outcome. METHODS: The MEDLINE database was searched for articles published between 1973 and 1999 which included the terms "biofeedback" and "fecal incontinence." Pediatric and adult articles in any language were screened. Inclusion for review required that the study be prospective, have five or more subjects, and have a description of the treatment protocol. RESULTS: Thirty-five studies were reviewed. Only six studies used a parallel treatment design and just three of those randomized subjects to treatment groups. A meta-analysis (weighted by subjects) was performed to compare the results of two treatment protocols that dominate the literature. The mean success rate of studies using Coordination training (i.e., coordinating pelvic floor muscle contraction with the sensation of rectal filling) was 67 percent, while the mean success rate for studies using Strength training (i.e., pelvic floor muscle contraction) was 70 percent. Furthermore, the mean success rate for those Strength training studies using electromyographic biofeedback was 74 percent, while the mean success rate for studies using anal canal pressure biofeedback Strength training was 64 percent. However, these conclusions are limited by the absence of clearly identified criteria for determining success. There are also inconsistencies in the literature regarding the patient selection criteria, severity and cause of symptoms, amount of treatment, as well as the type of biofeedback protocols and instrumentation used. Finally, no patient characteristics were identified that would assist in predicting successful outcome. CONCLUSION: Although most studies report positive results using biofeedback to treat fecal incontinence, quality research is lacking. Recommendations are made for future investigations to 1) improve experimental design, 2) include long term follow-up data, and 3) to use an adequate sample size that allows for meaningful analysis.


Assuntos
Biorretroalimentação Psicológica , Incontinência Fecal/terapia , Adulto , Canal Anal/fisiologia , Criança , Eletromiografia , Incontinência Fecal/psicologia , Humanos , Debilidade Muscular/terapia , Resultado do Tratamento
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