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1.
Ann R Coll Surg Engl ; 100(2): 120-124, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29046095

RESUMO

Introduction Surgically inserted rectus sheath catheters (RSCs) are used increasingly for analgesia after cystectomy and other abdominal surgery. Currently, there is little information on the optimal positioning of RSCs to allow maximal spread of local anaesthetic. This study sought to assess the spread of dye injected via RSCs and to highlight the extent of its coverage in a fresh unembalmed cadaveric cystectomy model in order to confirm the nerve endings that are likely to be anaesthetised with RSCs. Methods Four cadavers underwent lower midline incision with limited bladder mobilisation. A RSC was inserted into the eight hemiabdomens. The RSCs were positioned either anterior (n=5) or posterior to the rectus muscle (n=3). Dye was injected down the RSCs to evaluate spread. The eight hemiabdomens were dissected anatomically to determine the surface area of dye spread and nerve root involvement. Results The mean surface area of dye spread with anteriorly placed RSCs was 30.6cm2 anterior and 25.9cm2 posterior to the rectus muscle. The mean surface area of dye spread with posteriorly placed RSCs was 11.3cm2 anterior and 37.3cm2 posterior to the rectus muscle. The mean number of nerve roots stained with anteriorly and posteriorly placed RSCs was 3.8 and 2.7 respectively. Subcutaneous spread of dye was seen with one anterior RSC insertion. Peritoneal spread was seen with one anteriorly positioned RSC. Conclusions This study has demonstrated efficient nerve root infiltration with anteriorly and posteriorly positioned RSCs. It appears that dye spreads between the fibres of the rectus muscle rather than out laterally to the nerve roots when spreading from its initial compartment.


Assuntos
Catéteres , Cistectomia/instrumentação , Cistectomia/métodos , Reto do Abdome/cirurgia , Idoso de 80 Anos ou mais , Cadáver , Corantes , Feminino , Humanos , Masculino , Modelos Biológicos
2.
Ecology ; 98(7): 1787-1796, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28369822

RESUMO

To improve understanding of the complex and variable patterns of predator foraging behavior in natural systems, it is critical to determine how density-dependent predation and predator hunting success are mediated by alternate prey or predator interference. Despite considerable theory and debate seeking to place predator-prey interactions in a more realistic context, few empirical studies have quantified the role of alternate prey or intraspecific interactions on predator-prey dynamics. We assessed functional responses of two similarly sized, sympatric carnivores, lynx (Lynx canadensis) and coyotes (Canis latrans), foraging on common primary (snowshoe hares; Lepus americanus) and alternate (red squirrels; Tamiasciurus hudsonicus) prey in a natural system. Lynx exhibited a hyperbolic prey-dependent response to changes in hare density, which is characteristic of predators relying primarily on a single prey species. In contrast, the lynx-squirrel response was found to be linear ratio dependent, or inversely dependent on hare density. The coyote-hare and coyote-squirrel interactions also were linear and influenced by predator density. We explain these novel results by apparent use of spatial and temporal refuges by prey, and the likelihood that predators commonly experience interference and lack of satiation when foraging. Our study provides empirical support from a natural predator-prey system that (1) predation rate may not be limited at high prey densities when prey are small or rarely captured; (2) interference competition may influence the predator functional response; and (3) predator interference has a variable role across different prey types. Ultimately, distinct functional responses of predators to different prey types illustrates the complexity associated with predator-prey interactions in natural systems and highlights the need to investigate predator behavior and predation rate in relation to the broader ecological community.


Assuntos
Ecossistema , Comportamento Predatório , Animais , Coiotes , Lebres , Lynx , Dinâmica Populacional , Sciuridae
3.
Neuroscience ; 352: 52-63, 2017 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-28391014

RESUMO

Developmental alcohol exposure causes a host of cognitive and neuroanatomical abnormalities, one of which is impaired executive functioning resulting from medial prefrontal cortex (mPFC) damage. This study determined whether third-trimester equivalent alcohol exposure reduced the number of mPFC GABAergic parvalbumin-positive (PV+) interneurons, hypothesized to play an important role in local inhibition of the mPFC. The impact on passive avoidance learning and the therapeutic role of aerobic exercise in adulthood was also explored. Male C57BL/6J mice received either saline or 5g/kg ethanol (two doses, two hours apart) on PD 5, 7, and 9. On PD 35, animals received a running wheel or remained sedentary for 48days before behavioral testing and perfusion on PD 83. The number of PV+ interneurons was stereologically measured in three separate mPFC subregions: infralimbic, prelimbic and anterior cingulate cortices (ACC). Neonatal alcohol exposure decreased number of PV+ interneurons and volume of the ACC, but the other regions of the mPFC were spared. Alcohol impaired acquisition, but not retrieval of passive avoidance, and had no effect on motor performance on the rotarod. Exercise had no impact on PV+ cell number, mPFC volume, or acquisition of passive avoidance, but enhanced retrieval in both control and alcohol-exposed groups, and enhanced rotarod performance in the control mice. Results support the hypothesis that part of the behavioral deficits associated with developmental alcohol exposure are due to reduced PV+ interneurons in the ACC, but unfortunately exercise does not appear to be able to reverse any of these deficits.


Assuntos
Depressores do Sistema Nervoso Central/toxicidade , Etanol/toxicidade , Interneurônios/efeitos dos fármacos , Deficiências da Aprendizagem , Parvalbuminas/metabolismo , Condicionamento Físico Animal , Córtex Pré-Frontal/efeitos dos fármacos , Fatores Etários , Animais , Animais Recém-Nascidos , Aprendizagem da Esquiva/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Contagem de Células , Interneurônios/metabolismo , Deficiências da Aprendizagem/induzido quimicamente , Deficiências da Aprendizagem/patologia , Deficiências da Aprendizagem/reabilitação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Nestina/genética , Nestina/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Córtex Pré-Frontal/patologia , Transtornos Psicomotores/etiologia
4.
Behav Brain Res ; 314: 96-105, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27491590

RESUMO

Prenatal alcohol exposure can produce permanent alterations in brain structure and profound behavioral deficits. Mouse models can help discover mechanisms and identify potentially useful interventions. This study examined long-term influences of either a single or repeated alcohol exposure during the third-trimester equivalent on survival of new neurons in the hippocampus, behavioral performance on the Passive avoidance and Rotarod tasks, and the potential role of exercise as a therapeutic intervention. C57BL/6J male mice received either saline or 5g/kg ethanol split into two s.c. injections, two hours apart, on postnatal day (PD)7 (Experiment 1) or on PD5, 7 and 9 (Experiment 2). All mice were weaned on PD21 and received either a running wheel or remained sedentary from PD35-PD80/81. From PD36-45, mice received i.p. injections of 50mg/kg bromodeoxyuridine (BrdU) to label dividing cells. Behavioral testing occurred between PD72-79. Number of surviving BrdU+ cells and immature neurons (doublecortin; DCX+) was measured at PD80-81. Alcohol did not affect number of BrdU+ or DCX+ cells in either experiment. Running significantly increased number of BrdU+ and DCX+ cells in both treatment groups. Alcohol-induced deficits on Rotarod performance and acquisition of the Passive avoidance task (Day 1) were evident only in Experiment 2 and running rescued these deficits. These data suggest neonatal alcohol exposure does not result in long-term impairments in adult hippocampal neurogenesis in the mouse model. Three doses of ethanol were necessary to induce behavioral deficits. Finally, the mechanisms by which exercise ameliorated the neonatal alcohol induced behavioral deficits remain unknown.


Assuntos
Etanol/farmacologia , Hipocampo/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Animais , Comportamento Animal , Sobrevivência Celular/efeitos dos fármacos , Proteína Duplacortina , Hipocampo/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Neurogênese/fisiologia , Neurônios/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia
5.
Br J Anaesth ; 116(2): 277-81, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26787798

RESUMO

BACKGROUND: Local anaesthetics are commonly delivered to the epidural space by either intermittent bolus or continuous infusion. While these methods have been investigated in terms of analgesia and total dose administered, they have not been compared in terms of their effect on the spread of injectate within the epidural space. This animal study compared the spread of dye delivered to the epidural space in a porcine model by either bolus or infusion. METHODS: After ethical approval, epidural catheters were placed at three vertebral levels in seven anaesthetized pigs. Aqueous dye (1 ml) was injected into the catheter as a bolus, or as an infusion over 30 min. Animals were euthanized at the end of the study and necropsy performed immediately to quantify the extent of dye spread. RESULTS: In seven animals, 20 catheters were successfully placed in the epidural space. The mean (sd) extent of dye spread was 8.9 (2.6) cm in the infusion group compared with 15.2 (2.7) cm in the bolus group (P<0.001). Segmental spread was significantly greater in the bolus group compared with the infusion group (P<0.01). CONCLUSION: In the porcine epidural model, spread of one ml of epidural dye solution is more extensive after a single bolus compared with short term infusion.


Assuntos
Corantes/farmacocinética , Infusões Parenterais/métodos , Injeções Espinhais/métodos , Animais , Espaço Epidural , Injeções Epidurais , Modelos Animais , Suínos
6.
PeerJ ; 3: e1180, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26339557

RESUMO

The cause of mammalian cycles-the rise and fall of populations over a predictable period of time-has remained controversial since these patterns were first observed over a century ago. In spite of extensive work on observable mammalian cycles, the field has remained divided upon what the true cause is, with a majority of opinions attributing it to either predation or to intra-species mechanisms. Here we unite the eigenperiod hypothesis, which describes an internal, maternal effect-based mechanism to explain the cycles' periods with a recent generalization explaining the amplitude of snowshoe hare cycles in northwestern North America based on initial predator abundance. By explaining the period and the amplitude of the cycle with separate mechanisms, a unified and consistent view of the causation of cycles is reached. Based on our suggested theory, we forecast the next snowshoe hare cycle (predicted peak in 2016) to be of extraordinarily low amplitude.

7.
Rev Sci Instrum ; 86(7): 075005, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26233406

RESUMO

Abnormal blood clot stiffness is an important indicator of coagulation disorders arising from a variety of cardiovascular diseases and drug treatments. Here, we present a portable instrument for elastometry of microliter volume blood samples based upon the principle of resonant acoustic spectroscopy, where a sample of well-defined dimensions exhibits a fundamental longitudinal resonance mode proportional to the square root of the Young's modulus. In contrast to commercial thromboelastography, the resonant acoustic method offers improved repeatability and accuracy due to the high signal-to-noise ratio of the resonant vibration. We review the measurement principles and the design of a magnetically actuated microbead force transducer applying between 23 pN and 6.7 nN, providing a wide dynamic range of elastic moduli (3 Pa-27 kPa) appropriate for measurement of clot elastic modulus (CEM). An automated and portable device, the CEMport, is introduced and implemented using a 2 nm resolution displacement sensor with demonstrated accuracy and precision of 3% and 2%, respectively, of CEM in biogels. Importantly, the small strains (<0.13%) and low strain rates (<1/s) employed by the CEMport maintain a linear stress-to-strain relationship which provides a perturbative measurement of the Young's modulus. Measurements of blood plasma CEM versus heparin concentration show that CEMport is sensitive to heparin levels below 0.050 U/ml, which suggests future applications in sensing heparin levels of post-surgical cardiopulmonary bypass patients. The portability, high accuracy, and high precision of this device enable new clinical and animal studies for associating CEM with blood coagulation disorders, potentially leading to improved diagnostics and therapeutic monitoring.


Assuntos
Acústica/instrumentação , Testes de Coagulação Sanguínea/instrumentação , Microtecnologia/instrumentação , Análise Espectral/instrumentação , Anticoagulantes/farmacologia , Automação Laboratorial/instrumentação , Coagulação Sanguínea/efeitos dos fármacos , Coagulação Sanguínea/fisiologia , Calibragem , Ponte Cardiopulmonar , Relação Dose-Resposta a Droga , Módulo de Elasticidade , Desenho de Equipamento , Heparina/farmacologia , Humanos , Modelos Lineares , Imãs , Microesferas , Reprodutibilidade dos Testes , Razão Sinal-Ruído , Vibração
8.
Brain Plast ; 1(1): 83-95, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-28989863

RESUMO

New neurons are continuously generated in the adult hippocampus but their function remains a mystery. The nestin thymidine kinase (nestin-TK) transgenic method has been used for selective and conditional reduction of neurogenesis for the purpose of testing the functional significance of new neurons in learning, memory and motor performance. Here we explored the nestin-TK model on a hybrid genetic background (to increase heterozygosity, and "hybrid vigor"). Transgenic C57BL/6J (B6) were crossed with 129S1/SvImJ (129) producing hybrid offspring (F1) with the B6 half of the genome carrying a herpes simplex virus thymidine kinase (TK) transgene regulated by a modified nestin promoter. In the presence of exogenously administered valganciclovir, new neurons expressing TK undergo apoptosis. Female B6 nestin-TK mice (n = 80) were evaluated for neurogenesis reduction as a positive control. Male and female F1 nestin-TK mice (n = 223) were used to determine the impact of neurogenesis reduction on the Morris water maze (MWM) and rotarod. All mice received BrdU injections to label dividing cells and either valganciclovir or control chow, with or without a running wheel for 30 days. Both the F1 and B6 background displayed approximately 50% reduction in neurogenesis, a difference that did not impair learning and memory on the MWM or rotarod performance. Running enhanced neurogenesis and performance on the rotarod but not MWM suggesting the F1 background may not be suitable for studying pro-cognitive effects of exercise on MWM. Greater reduction of neurogenesis may be required to observe behavioral impacts. Alternatively, new neurons may not play a critical role in learning, or compensatory mechanisms in pre-existing neurons could have masked the deficits. Further work using these and other models for selectively reducing neurogenesis are needed to establish the functional significance of adult hippocampal neurogenesis in behavior.

9.
Clin Genet ; 84(4): 350-5, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23278385

RESUMO

Neurodegeneration with brain iron accumulation (NBIA) comprises a clinically and genetically heterogeneous group of neurodegenerative diseases characterized by progressive degeneration of the central nervous system and high basal ganglia iron deposition. The list of identified causative genes for NBIA syndromes continues to expand and includes one autosomal dominant, one X-linked, and a number of recessive forms. Mitochondrial membrane protein-associated neurodegeneration is a recently described NBIA syndrome caused by C19orf12 mutations. In this study, we report two consanguineous families with a homozygous C19orf12 p.Thr11Met mutation. Our patients presented at a later age and had more rapid disease progression, leading to early death in two, than those previously reported. We conclude that C19orf12 mutation is associated with wide phenotypic heterogeneity, and that further research is needed to examine the role of C19orf12 in NBIA and related diseases and to elucidate its protein function as well as other factors that may affect disease progression and expression.


Assuntos
Proteínas de Membrana/genética , Proteínas Mitocondriais/genética , Doenças Neurodegenerativas/genética , Adulto , Idade de Início , Encéfalo/metabolismo , Encéfalo/patologia , Cromossomos Humanos Par 19 , Consanguinidade , Progressão da Doença , Evolução Fatal , Humanos , Perda de Heterozigosidade , Imageamento por Ressonância Magnética , Masculino , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/metabolismo , Mutação , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/metabolismo , Linhagem , Polimorfismo de Nucleotídeo Único
10.
Ecology ; 93(7): 1707-16, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22919916

RESUMO

Determining the manner in which food webs will respond to environmental changes is difficult because the relative importance of top-down vs. bottom-up forces in controlling ecosystems is still debated. This is especially true in the Arctic tundra where, despite relatively simple food webs, it is still unclear which forces dominate in this ecosystem. Our primary goal was to assess the extent to which a tundra food web was dominated by plant-herbivore or predator-prey interactions. Based on a 17-year (1993-2009) study of terrestrial wildlife on Bylot Island, Nunavut, Canada, we developed trophic mass balance models to address this question. Snow Geese were the dominant herbivores in this ecosystem, followed by two sympatric lemming species (brown and collared lemmings). Arctic foxes, weasels, and several species of birds of prey were the dominant predators. Results of our trophic models encompassing 19 functional groups showed that <10% of the annual primary production was consumed by herbivores in most years despite the presence of a large Snow Goose colony, but that 20-100% of the annual herbivore production was consumed by predators. The impact of herbivores on vegetation has also weakened over time, probably due to an increase in primary production. The impact of predators was highest on lemmings, intermediate on passerines, and lowest on geese and shorebirds, but it varied with lemming abundance. Predation of collared lemmings exceeded production in most years and may explain why this species remained at low density. In contrast, the predation rate on brown lemmings varied with prey density and may have contributed to the high-amplitude, periodic fluctuations in the abundance of this species. Our analysis provided little evidence that herbivores are limited by primary production on Bylot Island. In contrast, we measured strong predator-prey interactions, which supports the hypothesis that this food web is primarily controlled by top-down forces. The presence of allochthonous resources subsidizing top predators and the absence of large herbivores may partly explain the predominant role of predation in this low-productivity ecosystem.


Assuntos
Artrópodes , Arvicolinae , Aves , Plantas , Animais , Regiões Árticas , Cadeia Alimentar , Modelos Biológicos , Modelos Estatísticos , Fatores de Tempo , Incerteza
11.
Proc Natl Acad Sci U S A ; 107(51): 21957-62, 2010 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-21098660

RESUMO

Ecological "surprises" are defined as unexpected findings about the natural environment. They are critically important in ecology because they are catalysts for questioning and reformulating views of the natural world, help shape assessments of the veracity of a priori predictions about ecological trends and phenomena, and underpin questioning of effectiveness of resource management. Despite the importance of ecological surprises, major gaps in understanding remain about how studies might be done differently or done better to improve the ability to identify them. We outline the kinds of ecological surprises that have arisen from long-term research programs that we lead in markedly different ecosystems around the world. Based on these case studies, we identify important lessons to guide both existing studies and new investigations to detect ecological surprises more readily, better anticipate unusual ecological phenomena, and take proactive steps to plan for and alleviate "undesirable" ecological surprises. Some of these lessons include: (i) maintain existing, and instigate new, long-term studies; (ii) conduct a range of kinds of parallel and concurrent research in a given target area; (iii) better use past literature and conceptual models of the target ecosystem in posing good questions and developing hypotheses and alternative hypotheses; and (iv) increase the capacity for ecological research to take advantage of opportunities arising from major natural disturbances. We argue that the increased anticipatory capability resulting from these lessons is critical given that ecological surprises may become more prevalent because of climate change and multiple and interacting environmental stressors.


Assuntos
Conservação dos Recursos Naturais , Ecologia/métodos , Ecossistema , Ecologia/tendências
12.
Plant Biol (Stuttg) ; 12(1): 215-23, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20653904

RESUMO

Interspecific hybridization can be a driving force for evolutionary processes during plant invasions, by increasing genetic variation and creating novel gene combinations, thereby promoting genetic differentiation among populations of invasive species in the introduced range. We examined regional genetic structure in the invasive Fallopia complex, consisting of F. japonica var. japonica, F. sachalinensis and their hybrid F. x bohemica, in seven regions in Germany and Switzerland using RAPD analysis and flow cytometry. All individuals identified as F. japonica var. japonica had the same RAPD phenotype, while F. sachalinensis (11 RAPD phenotypes for 11 sampled individuals) and F. x bohemica (24 RAPD phenotypes for 32 sampled individuals) showed high genotypic diversity. Bayesian cluster analysis revealed three distinct genetic clusters. The majority of F. x bohemica individuals were assigned to a unique genetic cluster that differed from those of the parental species, while the other F. x bohemica individuals had different degrees of admixture to the three genetic clusters. At the regional scale, the occurrence of male-fertile F. sachalinensis coincided with the distribution of F. x bohemica plants showing a high percentage of assignment to both parental species, suggesting that they originated from hybridization between the parental species. In contrast, in regions where male-fertile F. sachalinensis were absent, F. x bohemica belonged to the non-admixed genetic group, indicating multiple introductions of hybrids or sexual reproduction among hybrids. We also found regional differentiation in the gene pool of F. x bohemica, with individuals within the same region more similar to each other than to individuals from different regions.


Assuntos
Quimera , Hibridização Genética , Polygonaceae/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Teorema de Bayes , Análise por Conglomerados , DNA de Plantas/genética , Variação Genética , Genótipo , Geografia , Alemanha , Fenótipo , Polygonaceae/classificação , Análise de Sequência de DNA , Suíça
14.
Kidney Int ; 73(5): 643-50, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18033241

RESUMO

The C57BL/6 mouse strain serves as the genetic background of many transgenic and gene knockout models; however, this strain appears to be resistant to hypertension-induced renal injury. We developed a new model of hypertensive end-organ damage in C57BL/6 mice by combining deoxycorticosterone acetate (DOCA) and salt with angiotensin II infusion. The systolic blood pressure (SBP) was significantly elevated in DOCA salt-angiotensin II mice compared to control mice or mice treated individually with DOCA salt or angiotensin II. Hypertensive glomerular damage, increased expression of profibrotic and inflammatory genes, albuminuria, tubular casts, increased plasma cholesterol, cardiac hypertrophy, and fibrosis were found in mice treated with DOCA salt-angiotensin II. The SBP in the angiotensin II-infused group was further increased by increasing the infusion rate; only mild injury was observed in these mice, suggesting that blood pressure was not a causal factor. Removal of DOCA and the angiotensin pump lowered blood pressure to normal; however, albuminuria along with the glomerular and cardiac damage did not completely resolve. Our study describes a new model of hypertensive end-organ damage and repair in C57BL/6 mice.


Assuntos
Modelos Animais de Doenças , Hipertensão/complicações , Falência Renal Crônica/etiologia , Camundongos , Angiotensina II/toxicidade , Animais , Pressão Sanguínea , Peso Corporal , Desoxicorticosterona/toxicidade , Hipertensão/induzido quimicamente , Falência Renal Crônica/patologia , Falência Renal Crônica/fisiopatologia , Glomérulos Renais/fisiopatologia , Glomérulos Renais/ultraestrutura , Masculino , Mineralocorticoides/toxicidade , Miocárdio/patologia , Proteinúria/etiologia , Vasoconstritores/toxicidade
15.
Kidney Int ; 72(6): 725-30, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17597696

RESUMO

Recently, a (pro)renin receptor has been identified which mediates profibrotic effects independent of angiotensin II. Because antihypertensive therapy induces renal injury in the clipped kidney of two kidney-1-clip hypertensive rats, we examined the regulation of renin and the (pro)renin receptor in this model. Hypertensive Goldblatt rats were treated with increasing doses of the vasopeptidase inhibitor AVE 7688 after which the plasma renin and prorenin as well as the renal renin and (pro)renin receptor expression were measured. The vasopeptidase inhibitor dose-dependently lowered blood pressure, which was associated with a massive increase in plasma prorenin and renin as well as increased renal renin expression. The (pro)renin receptor was upregulated in the clipped kidney of the Goldblatt rat indicating a parallel upregulation of renin and its receptor in vivo. Immunohistochemistry showed a redistribution of renin upstream from the glomerulus in preglomerular vessels and renin staining in tubular cells. Expression of the (pro)renin receptor was increased in the vessels and tubules. This upregulation was associated with thickening of renin-positive vessels and tubulointerstitial damage. We propose that renin and the (pro)renin receptor may play a profibrotic role in the clipped kidney of Goldblatt rats treated for hypertension.


Assuntos
Compostos Heterocíclicos com 3 Anéis/farmacologia , Hipertensão Renovascular/tratamento farmacológico , Hipertensão Renovascular/metabolismo , Pró-Fármacos/farmacologia , Receptores de Superfície Celular/metabolismo , Renina/metabolismo , Animais , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Hipertensão Renovascular/patologia , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley , Instrumentos Cirúrgicos , Regulação para Cima/efeitos dos fármacos , Receptor de Pró-Renina
16.
Am J Physiol Renal Physiol ; 292(2): F876-87, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17062848

RESUMO

The present study examined the pathogenesis of interstitial inflammation and fibrosis in antihypertensively treated rats with two-kidney, one-clip hypertension. Hypertensive rats were randomized into four groups: no treatment and moderate, intermediate, and intensified lowering of blood pressure with increasing doses of a vasopeptidase inhibitor for 6 wk. The vasopeptidase inhibitor dose dependently lowered blood pressure. The tubulointerstitial damage was accompanied by a diffuse infiltration of mononuclear cells and circumscript mononuclear inflammatory cell cluster formation consisting mainly of T cells and to a lesser degree of macrophages and B cells. Real-time PCR analyses showed a dose-dependent induction of MCP-1 and the Th1-type chemokines IP10 and Mig as well as their receptor CXCR3 and the Th1 cytokine IFN-gamma. In situ hybridization and laser microdissection revealed a strong expression of these Th1-associated transcripts in the clusters and, in the case of MCP-1, also diffusely in the interstitium. The inflammation was accompanied by the appearance of myofibroblasts and synthesis of the fibrogenic factor plasminogen activator inhibitor-1 as well as the collagenase matrix metalloproteinase-2, leading to collagen I upregulation and interstitial scarring. No inflammation or fibrosis was found in normotensive rats treated with the vasopeptidase inhibitor. The renal injury in the clipped kidney is accompanied by compartment-specific chemokine expression and cell cluster formation of Th1 specificity associated with upregulation of fibrogenic proteins and matrix metalloproteinases. These findings suggest that the Th1 chemokines IP10 and Mig as well as their receptor CXCR3 are potential targets for therapeutic interventions in ischemic nephropathy.


Assuntos
Anti-Hipertensivos/uso terapêutico , Quimiocinas/biossíntese , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Hipertensão Renovascular/tratamento farmacológico , Hipertensão Renovascular/imunologia , Células Th1/imunologia , Actinas/biossíntese , Animais , Quimiocina CCL2/biossíntese , Quimiocina CXCL10 , Quimiocina CXCL9 , Quimiocinas CXC/biossíntese , Creatinina/sangue , Fibrose , Expressão Gênica , Hipertensão Renovascular/patologia , Imuno-Histoquímica , Hibridização In Situ , Molécula 1 de Adesão Intercelular/biossíntese , Interferon gama/biossíntese , Rim/patologia , Masculino , Metaloproteinase 2 da Matriz/biossíntese , Osteopontina/biossíntese , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Ratos , Ratos Sprague-Dawley
17.
Arq. neuropsiquiatr ; 63(3B): 862-863, set. 2005. ilus
Artigo em Inglês | LILACS | ID: lil-445130

RESUMO

We present a case of a severe head injured 23 year-old male patient. The initial CT scan disclosed bilateral epidural hematoma, isodense with the brain, thus being a pitfall in diagnosis. Brief case report, image and literature review are presented.


Apresentamos o caso de um homem de 23 anos com traumatismo craniano grave. A TC de crânio demonstrou um volumoso hematoma epidural bilateral, isodenso com o cérebro, sendo uma armadilha ao diagnóstico. São apresentados um breve relato, estudo da imagem tomográfica e revisão da literatura.


Assuntos
Humanos , Adulto , Masculino , Encéfalo , Hematoma Epidural Craniano , Fraturas Cranianas , Escala de Coma de Glasgow , Tomografia Computadorizada por Raios X
18.
Mol Ecol ; 14(5): 1585-96, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15813796

RESUMO

Reliable population estimates are necessary for effective conservation and management, and faecal genotyping has been used successfully to estimate the population size of several elusive mammalian species. Information such as changes in population size over time and survival rates, however, are often more useful for conservation biology than single population estimates. We evaluated the use of faecal genotyping as a tool for monitoring long-term population dynamics, using coyotes (Canis latrans) in the Alaska Range as a case study. We obtained 544 genotypes from 56 coyotes over 3 years (2000-2002). Tissue samples from all 15 radio-collared coyotes in our study area had > or = 1 matching faecal genotypes. We used flexible maximum-likelihood models to study coyote population dynamics, and we tested model performance against radio telemetry data. The staple prey of coyotes, snowshoe hares (Lepus americanus), dramatically declined during this study, and the coyote population declined nearly two-fold with a 1(1/2)-year time lag. Survival rates declined the year after hares crashed but recovered the following year. We conclude that long-term monitoring of elusive species using faecal genotyping is feasible and can provide data that are useful for wildlife conservation and management. We highlight some drawbacks of standard open-population models, such as low precision and the requirement of discrete sampling intervals, and we suggest that the development of open models designed for continuously collected data would enhance the utility of faecal genotyping as a monitoring tool.


Assuntos
Coiotes/fisiologia , Fezes/química , Modelos Biológicos , Densidade Demográfica , Alaska , Animais , Conservação dos Recursos Naturais/métodos , Coiotes/genética , Impressões Digitais de DNA , Primers do DNA , Demografia , Genótipo , Funções Verossimilhança , Repetições de Microssatélites/genética , Dinâmica Populacional , Análise para Determinação do Sexo/métodos
19.
Mol Ecol ; 13(1): 195-202, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14653799

RESUMO

Sexual selection should produce sexual size dimorphism in species where larger members of one sex obtain disproportionately more matings. Recent theory suggests that the degree of sexual size dimorphism depends on physical and temporal constraints involving the operational sex ratio, the potential reproductive rate and the trade-off between current reproductive effort and residual reproductive value. As part of a large-scale experiment on dispersal, we investigated the mating system of common brushtail possums inhabiting old-growth Eucalyptus forest in Australia. Paternity was assigned to 20 of 28 pouch-young (maternity known) genotyped at six microsatellite loci. Male mating success was strongly related to body size and age; male body weight and age being highly correlated. Despite disproportionate mating success favouring larger males, sexual size dimorphism was only apparent among older animals. Trapping and telemetry indicated that the operational sex ratio was effectively 1 : 1 and the potential reproductive rate of males was at most four times that of females. Being larger appeared to entail significant survival costs because males 'died-off' at the age at which sexual size dimorphism became apparent (8-9 years). Male and female home ranges were the same size and males appeared to be as sedentary as females. Moreover, longevity appears to be only slightly less important to male reproductive success than it is to females. It is suggested that a sedentary lifestyle and longevity are the key elements constraining selection for greater sexual size dimorphism in this 'model' medium-sized Australian marsupial herbivore.


Assuntos
Genética Populacional , Marsupiais/genética , Reprodução/fisiologia , Seleção Genética , Caracteres Sexuais , Fatores Etários , Animais , Constituição Corporal , Frequência do Gene , Comportamento de Retorno ao Território Vital/fisiologia , Longevidade , Marsupiais/fisiologia , Repetições de Microssatélites/genética , New South Wales , Razão de Masculinidade
20.
J Gambl Stud ; 17(2): 117-36, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11705207

RESUMO

Problem gambling is a common, highly destructive disorder which is often overlooked by clinicians. Levels of clinical training, clinical experience, and professional competence for providing clinical services for problem gambling were examined in a survey of 181 clinical psychologists working in the Veterans Healthcare Administration (VHA). The results suggest that the majority of clinical psychologists have little or no formal training and little or no past or current clinical experience in the treatment of disordered gambling, nor do they see themselves as competent to evaluate or treat patients with disordered gambling. Most have not referred patients for treatment of problem gambling and do not know of a competent provider to whom they can refer. There is an identifiable subgroup, representing 9% of respondents, who do have more training, provide services, and see themselves as competent to provide care for patients with problem gambling. The amount of formal training is positively correlated with care provided and self-ratings of competence. Despite the lack of training and experience, most respondents expressed interest in receiving additional training. These data suggest that to improve rates of diagnosis and treatment of patients with problem gambling in mental health settings, additional training needs to be made available for mental health providers as a group, with specialized training for clinicians interested in specializing in this area.


Assuntos
Jogo de Azar/psicologia , Competência Profissional , Psicologia Clínica/educação , Psicoterapia/educação , Veteranos/psicologia , Adulto , Currículo , Educação Continuada , Educação de Pós-Graduação , Feminino , Hospitais de Veteranos , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos
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