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1.
Proc Biol Sci ; 287(1938): 20201585, 2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33171084

RESUMO

Competition for shared resources represents a fundamental driver of biological diversity. However, the tempo and mode of phenotypic evolution in deep-time has been predominantly investigated using trait evolutionary models which assume that lineages evolve independently from each other. Consequently, the role of species interactions in driving macroevolutionary dynamics remains poorly understood. Here, we quantify the prevalence for signatures of competition between related species in the evolution of ecomorphological traits across the bird radiation. We find that mechanistic trait models accounting for the effect of species interactions on phenotypic divergence provide the best fit for the data on at least one trait axis in 27 out of 59 clades ranging between 21 and 195 species. Where it occurs, the signature of competition generally coincides with positive species diversity-dependence, driven by the accumulation of lineages with similar ecologies, and we find scarce evidence for trait-dependent or negative diversity-dependent phenotypic evolution. Overall, our results suggest that the footprint of interspecific competition is often eroded in long-term patterns of phenotypic diversification, and that other selection pressures may predominantly shape ecomorphological diversity among extant species at macroevolutionary scales.


Assuntos
Evolução Biológica , Aves , Animais , Fenótipo , Filogenia
2.
Drug Dev Ind Pharm ; 45(3): 379-386, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30395722

RESUMO

OBJECTIVE: The aim of this study is to demonstrate the applicability of predictive stability studies to the degradation of drug substances. SIGNIFICANCE: The use of predicted stability studies during pharmaceutical development and in regulatory submissions is increasing, particularly in early phase to support an initial retest period/shelf life claim in the absence of standard stability data. These studies offer an alternative to standard stability testing and can facilitate clinical trials to be started earlier and medicines to reach patients faster. They involve a short-term stressed stability study, typically designed to degrade a drug substance or product to the specification level of the shelf life limiting attribute. The results are used to predict degradation under long-term storage conditions and enable stability understanding to be gained over a short time frame, using limited amounts of material. METHODS: In this work, Accelerated Stability Assessment Program (ASAP) studies were performed for 10 different drug substances and the predictions obtained for chemical degradation were compared to ICH compliant stability data. RESULTS: Across the studies good agreement was achieved, with the initial retest period predictions from the ASAP studies being conservative by design. When minimal degradation was observed during an ASAP study, it was demonstrated that at least a 12-month initial retest period could be supported. CONCLUSION: This comparison of ASAP predictions and ICH compliant stability data has demonstrated the ability of well-designed ASAP studies to predict the long-term chemical stability of drug substances.


Assuntos
Estabilidade de Medicamentos , Preparações Farmacêuticas/química , Química Farmacêutica/métodos , Embalagem de Medicamentos/métodos , Armazenamento de Medicamentos/métodos , Humanos , Tecnologia Farmacêutica/métodos
3.
Ecol Lett ; 21(10): 1505-1514, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30133084

RESUMO

Heterogeneity in rates of trait evolution is widespread, but it remains unclear which processes drive fast and slow character divergence across global radiations. Here, we test multiple hypotheses for explaining rate variation in an ecomorphological trait (beak shape) across a globally distributed group (birds). We find low support that variation in evolutionary rates of species is correlated with life history, environmental mutagenic factors, range size, number of competitors, or living on islands. Indeed, after controlling for the negative effect of species' age, 80% of variation in species-specific evolutionary rates remains unexplained. At the clade level, high evolutionary rates are associated with unusual phenotypes or high species richness. Taken together, these results imply that macroevolutionary rates of ecomorphological traits are governed by both ecological opportunity in distinct adaptive zones and niche differentiation among closely related species.


Assuntos
Evolução Biológica , Ecologia , Animais , Masculino , Fenótipo , Filogenia
4.
Vet Pathol ; 52(2): 338-43, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24810909

RESUMO

Pheochromocytoma-associated catecholamine-induced cardiomyopathy is a well-known entity in man, nonhuman primates, and mice but has not been described in dogs. In this retrospective study, 9 dogs were identified with pheochromocytomas and concurrent cardiovascular pathology observed histologically (n = 6), echocardiographically (n = 4), and/or electrocardiographically (n = 5). Cardiac lesions included multifocal cardiomyocyte necrosis with contraction bands, cardiomyocyte degeneration, myocardial hemorrhage, lymphohistiocytic myocarditis, and interstitial fibrosis. Clinical procedures, including electrocardiographic and echocardiographic examinations, Doppler blood pressure measurement, and auscultation, were available for 5 dogs and consistently revealed concentric or mixed (eccentric and concentric) ventricular hypertrophy. Additional changes observed included arrhythmias, systemic hypertension, and heart murmurs. The myocardial lesions observed in this series of dogs are similar to those observed in humans with pheochromocytoma-associated catecholamine-induced cardiomyopathy. Since the clinical manifestations of catecholamine-induced cardiac disease are amenable to medical treatment, recognition of this cardiomyopathy has the potential to reduce morbidity and mortality in dogs with pheochromocytoma.


Assuntos
Neoplasias das Glândulas Suprarrenais/veterinária , Arritmias Cardíacas/veterinária , Cardiomiopatias/veterinária , Doenças do Cão/patologia , Feocromocitoma/veterinária , Neoplasias das Glândulas Suprarrenais/patologia , Animais , Arritmias Cardíacas/patologia , Cardiomiopatias/patologia , Cães , Eletrocardiografia/veterinária , Feminino , Masculino , Camundongos , Miocárdio/patologia , Miócitos Cardíacos/patologia , Feocromocitoma/patologia , Estudos Retrospectivos
5.
Br J Cancer ; 106(10): 1702-12, 2012 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-22531638

RESUMO

BACKGROUND: Brain tumour stem cells (BTSCs) are a small population of cancer cells that exhibit self-renewal, multi-drug resistance, and recurrence properties. We have shown earlier that peroxisome proliferator-activated receptor gamma (PPARγ) agonists inhibit the expansion of BTSCs in T98G and U87MG glioma. In this study, we analysed the influence of PPARγ agonists on the expression of stemness and differentiation genes in BTSCs. METHODS: The BTSCs were isolated from T98G and DB29 glioma cells, and cultured in neurobasal medium with epidermal growth factor+basic fibroblast growth factor. Proliferation was measured by WST-1 (4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2 H-5-tetrazolio]-1,3-benzene disulphonate) and 3H thymidine uptake assays, and gene expression was analysed by quantitative reverse--transcription PCR and Taqman array. The expression of CD133, SRY box 2, and nanog homeobox (Nanog) was also evaluated by western blotting, immunostaining, and flow cytometry. RESULTS: We found that PPARγ agonists, ciglitazone and 15-deoxy-Δ(12,14)-ProstaglandinJ(2), inhibited cell viability and proliferation of T98G- and DB29-BTSCs. The PPARγ agonists reduced the expansion of CD133(+) BTSCs and altered the expression of stemness and differentiation genes. They also inhibited Sox2 while enhancing Nanog expression in BTSCs. CONCLUSION: These findings highlight that PPARγ agonists inhibit BTSC proliferation in association with altered expression of Sox2, Nanog, and other stemness genes. Therefore, targeting stemness genes in BTSCs could be a novel strategy in the treatment of glioblastoma.


Assuntos
Neoplasias Encefálicas/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , PPAR gama/agonistas , Neoplasias Encefálicas/tratamento farmacológico , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Glioma/tratamento farmacológico , Glioma/patologia , Proteínas de Homeodomínio/análise , Humanos , Proteína Homeobox Nanog , Células-Tronco Neoplásicas/citologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOXB1/análise
6.
Lancet ; 378(9786): 129-39, 2011 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-21705068

RESUMO

BACKGROUND: Lifestyle changes soon after diagnosis might improve outcomes in patients with type 2 diabetes mellitus, but no large trials have compared interventions. We investigated the effects of diet and physical activity on blood pressure and glucose concentrations. METHODS: We did a randomised, controlled trial in southwest England in adults aged 30-80 years in whom type 2 diabetes had been diagnosed 5-8 months previously. Participants were assigned usual care (initial dietary consultation and follow-up every 6 months; control group), an intensive diet intervention (dietary consultation every 3 months with monthly nurse support), or the latter plus a pedometer-based activity programme, in a 2:5:5 ratio. The primary endpoint was improvement in glycated haemoglobin A(1c)(HbA(1c)) concentration and blood pressure at 6 months. Analysis was done by intention to treat. This study is registered, number ISRCTN92162869. FINDINGS: Of 593 eligible individuals, 99 were assigned usual care, 248 the diet regimen, and 246 diet plus activity. Outcome data were available for 587 (99%) and 579 (98%) participants at 6 and 12 months, respectively. At 6 months, glycaemic control had worsened in the control group (mean baseline HbA(1c) percentage 6·72, SD 1·02, and at 6 months 6·86, 1·02) but improved in the diet group (baseline-adjusted difference in percentage of HbA(1c) -0·28%, 95% CI -0·46 to -0·10; p=0·005) and diet plus activity group (-0·33%, -0·51 to -0·14; p<0·001). These differences persisted to 12 months, despite less use of diabetes drugs. Improvements were also seen in bodyweight and insulin resistance between the intervention and control groups. Blood pressure was similar in all groups. INTERPRETATION: An intensive diet intervention soon after diagnosis can improve glycaemic control. The addition of an activity intervention conferred no additional benefit. FUNDING: Diabetes UK and the UK Department of Health.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Diabetes Mellitus Tipo 2/dietoterapia , Terapia por Exercício , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Análise de Intenção de Tratamento , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Redução de Peso
7.
Genes Immun ; 12(1): 1-14, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20861865

RESUMO

Multiple sclerosis (MS) is a neurological disorder that causes paralysis in young adults and affects women more frequently than men. The etiology of MS is not known, but it is generally viewed as an autoimmune disease of the central nervous system (CNS), influenced by genetic and environmental factors. Recent studies have identified interleukin-7 receptor α (IL-7Rα) as a risk factor for MS. But the role of IL-7Rα in experimental autoimmune encephalomyelitis (EAE) model of MS is not known. In this study we demonstrate that IL-7Rα-deficient (IL-7Rα(-/-)) mice remain resistant to MOGp35-55-induced EAE. When compared with C57BL/6 wild-type mice, IL-7Rα(-/-) mice showed less severe inflammation and demyelination in the CNS. The attenuation of EAE in IL-7Rα(-/-) mice was associated with a decrease in T-helper (Th) 1 and Th17 responses in the CNS and lymphoid organs. IL-7Rα(-/-) mice also showed an increase in Th2 response and CD4(+)Foxp3(+) regulatory T cells. These findings highlight that IL-7Rα confers susceptibility by influencing autoimmune Th1/Th17 responses in EAE model of MS.


Assuntos
Encefalomielite Autoimune Experimental/genética , Predisposição Genética para Doença , Receptores de Interleucina-7/genética , Animais , Autoantígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Encefalomielite Autoimune Experimental/imunologia , Feminino , Interleucina-4/imunologia , Masculino , Camundongos , Bainha de Mielina/metabolismo , Receptores de Interleucina-7/metabolismo , Linfócitos T Reguladores/imunologia
8.
Br J Cancer ; 104(3): 448-59, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21224854

RESUMO

BACKGROUND: Brain tumours present unique challenges to conventional therapies and pose major health problems around the world. Brain tumour stem cells (BTSCs) represent a small fraction of tumour cells that maintain growth, drug resistance and recurrence properties. Constitutive androstane receptor (CAR) is a nuclear receptor transcription factor that regulates drug metabolism and homoeostasis. In this study, we examined the effect of CAR agonist, 6-(4-chlorophenyl)imidazo[2,1-b][1,3]thiazole-5-carbaldehydeO-(3,4-dichlorobenzyl)oxime (CITCO) on BTSCs. METHODS: The expression of CAR in BTSCs was detected by quantitative RT-PCR and western blot. The antiproliferative effect of CITCO on BTSCs was determined by WST-1 and (3)H thymidine uptake assays. The effect of CITCO on CD133 expression, cell cycle progression and apoptosis in BTSCs was analysed by immunostaining and flow cytometry. The in vivo effect of CITCO was studied using subcutaneous (s.c.) BTSC xenograft in nude mice. RESULTS: We show for the first time that BTSCs express altered levels of nuclear receptors compared with glioma cells. The expression of CAR mRNA and protein was low in BTSCs and that increased following treatment with CITCO in culture. CITCO induced a dose-dependent decrease in growth and expansion of CD133(+) BTSCs as gliospheres in culture. Cell cycle arrest and apoptosis in BTSCs were induced by CITCO, but not in normal astrocytes. Growth of s.c BTSC xenograft in nude mice was also inhibited by CITCO. CONCLUSION: These findings indicate that CITCO inhibits the growth and expansion of BTSCs, suggesting the use of CAR agonists for the treatment of brain tumour.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Oximas/farmacologia , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/farmacologia , Tiazóis/farmacologia , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Receptor Constitutivo de Androstano , Humanos , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Vet Pathol ; 48(6): 1061-74, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21383115

RESUMO

West Nile virus (WNV)-associated disease has a range of clinical manifestations among avian taxa, the reasons for which are not known. Species susceptibility varies within the avian family Corvidae, with estimated mortality rates ranging from 50 to 100%. We examined and compared virologic, immunologic, pathologic, and clinical responses in 2 corvid species, the American crow (Corvus brachyrhynchos) and the fish crow (C ossifragus), following experimental WNV inoculation. Unlike fish crows, which remained clinically normal throughout the study, American crows succumbed to WNV infection subsequent to dehydration, electrolyte and pH imbalances, and delayed or depressed humoral immune responses concurrent with marked, widespread virus replication. Viral titers were approximately 3,000 times greater in blood and 30,000 to 50,000 times greater in other tissues (eg, pancreas and small intestine) in American crows versus fish crows. Histologic lesion patterns and antigen deposition supported the differing clinical outcomes, with greater severity and distribution of lesions and WNV antigen in American crows. Both crow species had multiorgan necrosis and inflammation, although lesions were more frequent, severe, and widespread in American crows, in which the most commonly affected tissues were small intestine, spleen, and liver. American crows also had inflammation of vessels and nerves in multiple tissues, including heart, kidney, and the gastrointestinal tract. WNV antigen was most commonly observed within monocytes, macrophages, and other cells of the reticuloendothelial system of affected tissues. Collectively, the data support that WNV-infected American crows experience uncontrolled systemic infection leading to multiorgan failure and rapid death.


Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Doenças das Aves/patologia , Corvos/virologia , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/imunologia , Animais , Animais Selvagens , Doenças das Aves/mortalidade , Doenças das Aves/virologia , Eletrocardiografia/veterinária , Fezes/virologia , Especificidade da Espécie , Viremia/veterinária , Replicação Viral , Febre do Nilo Ocidental/mortalidade , Febre do Nilo Ocidental/patologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/isolamento & purificação , Vírus do Nilo Ocidental/fisiologia
10.
Emerg Med J ; 28(4): 287-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20581387

RESUMO

OBJECTIVES: To validate the objective criteria in the Department of Health Adult Swine Flu Assessment Tool against proxy datasets for pandemic influenza. DESIGN: Comparative validation study with 3 datasets. SETTING: Urban Emergency Department (group 1) and prehospital care (groups 2 and 3). PARTICIPANTS: Adults with community-acquired pneumonia (group 1, n=281), shortness of breath (group 2, n=211) or any respiratory diagnosis (group 3, n=300). OUTCOME MEASURES: Hospital admission (group 1), hospital admission or intravenous therapy (group 2) and transfer to emergency department (group 3). RESULTS: Sensitivity and specificity of the tool were 0.73 (95% CI 0.67 to 0.8) and 0.83 (0.72 to 0.9) in group 1, 0.64 (0.55 to 0.71) and 0.63 (0.52 to 0.73) in group 2 and 0.84 (0.75 to 0.9) and 0.55 (0.48 to 0.62) in group 3. Analysis of individual components of the tool and a summative score is presented. CONCLUSIONS: The objective criteria of the proposed DH assessment tool do not perform particularly well in predicting relevant clinical outcomes in feasible proxy conditions for pandemic influenza.


Assuntos
Infecções Comunitárias Adquiridas/diagnóstico , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/diagnóstico , Guias de Prática Clínica como Assunto , Adolescente , Adulto , Idoso , Comorbidade , Tomada de Decisões , Serviço Hospitalar de Emergência , Inglaterra/epidemiologia , Feminino , Escala de Coma de Glasgow , Humanos , Influenza Humana/epidemiologia , Masculino , Pessoa de Meia-Idade , Pandemias , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
11.
Br J Cancer ; 99(12): 2044-53, 2008 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-19018263

RESUMO

Brain tumour stem cells (BTSCs) are a small population of cells that has self-renewal, transplantation, multidrug resistance and recurrence properties, thus remain novel therapeutic target for brain tumour. Recent studies have shown that peroxisome proliferator-activated receptor gamma (PPARgamma) agonists induce growth arrest and apoptosis in glioblastoma cells, but their effects on BTSCs are largely unknown. In this study, we generated gliospheres with more than 50% CD133+ BTSC by culturing U87MG and T98G human glioblastoma cells with epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF). In vitro treatment with PPARgamma agonist, 15-Deoxy-Delta(12,14)-Prostaglandin J(2) (15d-PGJ2) or all-trans retinoic acid resulted in a reversible inhibition of gliosphere formation in culture. Peroxisome proliferator-activated receptor gamma agonists inhibited the proliferation and expansion of glioma and gliosphere cells in a dose-dependent manner. Peroxisome proliferator-activated receptor gamma agonists also induced cell cycle arrest and apoptosis in association with the inhibition of EGF/bFGF signalling through Tyk2-Stat3 pathway and expression of PPARgamma in gliosphere cells. These findings demonstrate that PPARgamma agonists regulate growth and expansion of BTSCs and extend their use to target BTSCs in the treatment of brain tumour.


Assuntos
Antígenos CD/metabolismo , Glicoproteínas/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , PPAR gama/agonistas , Peptídeos/metabolismo , Prostaglandina D2/análogos & derivados , Tretinoína/farmacologia , Antígeno AC133 , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Humanos , Janus Quinases/metabolismo , PPAR gama/metabolismo , Prostaglandina D2/farmacologia , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais/efeitos dos fármacos
12.
J Vet Intern Med ; 22(2): 351-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18371029

RESUMO

BACKGROUND: Associations of age and heart rate with blood flow velocities and durations assessed by pulsed-wave (PW) Doppler echocardiography in cats are incompletely understood. OBJECTIVES: To determine the effects of age and heart rate on blood flow velocities and durations of cardiac events obtained by PW Doppler echocardiography in healthy, nonsedated cats. ANIMALS: A convenience sample of 87 healthy, nonsedated cats aged 3 months to 19 years. METHODS: Prospective, observational study. PW Doppler measurements were obtained by echocardiography. Association of age and heart rate with PW Doppler values was evaluated by simple and multiple linear regressions and ANCOVA. RESULTS: Significant weak positive relationships were found between age and isovolumic relaxation time (IVRT) (R2= 0.18; P< or = .001), and between age and duration of pulmonary venous retrograde flow (R2= 0.07; P= .041). There was a significant weak negative relationship between age and transmitral peak early diastolic velocity (R2= 0.19; P< or = .001). Age and heart rate were significantly related to pulmonary venous peak systolic velocity (R2= 0.13; P= .008). Heart rate affected transmitral peak late diastolic velocity (R2= 0.11; P= .006). After adjusting for heart rate effect, the PW Doppler variables that were significantly different between age groups were transmitral peak early diastolic velocity (P< or = .001), duration of transmitral late diastolic flow (P< or = .001), IVRT (P< or = .001), and the ratio of duration of transmitral late diastolic flow to duration of pulmonary venous retrograde flow (P= .029). CONCLUSIONS AND CLINICAL IMPORTANCE: The association of several PW Doppler-derived variables and age and heart rate is weak and not clinically important.


Assuntos
Envelhecimento/fisiologia , Gatos/fisiologia , Ecocardiografia Doppler de Pulso/veterinária , Frequência Cardíaca/fisiologia , Animais
13.
J Vet Intern Med ; 22(1): 114-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18289297

RESUMO

BACKGROUND: Atrial fibrillation (AF) in dogs can be managed by electrical cardioversion to sinus rhythm, but early recurrence of AF occurs in some dogs. In humans, the commonly evaluated clinical variables for prediction of early relapse of AF are left atrial size and duration of AF. It is unclear whether the duration of AF affects maintenance of sinus rhythm after cardioversion in dogs with spontaneous AF. HYPOTHESIS: That duration of sinus rhythm after cardioversion is related to the chronicity of AF. ANIMALS: Forty-one consecutive dogs that had undergone successful transthoracic cardioversion for spontaneous AF were evaluated. METHODS: The relationship between the duration of documented AF and the duration of sinus rhythm after cardioversion was statistically evaluated using data obtained retrospectively. The effects of structural heart disease and pretreatment with amiodarone were also evaluated. RESULTS: The presence of structural heart disease and the duration of documented AF had significant effects on maintenance of sinus rhythm after cardioversion (P <.001 and P=.022, respectively). The duration of documented AF was inversely related to the duration of sinus rhythm (P=.022) in dogs with and without structural heart disease. CONCLUSIONS AND CLINICAL IMPORTANCE: Estimates of duration of sinus rhythm based on the duration of documented AF are provided for dogs with and without heart disease allowing prediction of risk for early AF relapse.


Assuntos
Fibrilação Atrial/veterinária , Doenças do Cão/terapia , Cardioversão Elétrica/veterinária , Amiodarona/uso terapêutico , Animais , Antiarrítmicos/uso terapêutico , Fibrilação Atrial/terapia , Doença Crônica , Cães , Recidiva , Estudos Retrospectivos , Fatores de Tempo
14.
Respir Med ; 101(4): 857-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17029770

RESUMO

Vocal cord dysfunction (VCD) is characterised by paradoxical vocal cord adduction during inspiration or throughout the respiratory cycle, it results in wheeze, stridor, cough and dyspnoea. Although asthma and VCD can coexist, patients with VCD are frequently misdiagnosed with refractory asthma. It can severely restrict an individual's level of activity and effective therapeutic control can be difficult to achieve. We report the case of a patient who was treated with all available therapeutic interventions, including intralaryngeal botulinum toxin injection, but failure resulted in a permanent trachesotomy.


Assuntos
Doenças da Laringe/terapia , Prega Vocal/fisiopatologia , Adulto , Antidiscinéticos/administração & dosagem , Asma/complicações , Asma/tratamento farmacológico , Toxinas Botulínicas/administração & dosagem , Humanos , Injeções , Doenças da Laringe/complicações , Doenças da Laringe/fisiopatologia , Masculino , Terapia Respiratória/métodos , Fonoterapia/métodos , Traqueostomia/métodos , Falha de Tratamento
15.
J Small Anim Pract ; 48(6): 335-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17547642

RESUMO

This report describes a dog with recurrent atrial fibrillation and atrial flutter associated with chronic gastritis. Although no underlying structural heart disease was apparent antemortem or on gross post-mortem examination, chronic atrial myocarditis was seen on histopathological examination. Atrial myocarditis is a recognised cause of atrial fibrillation in human beings with presumed lone fibrillation, and an association between supraventricular tachyarrhythmias and infectious agents has been made.


Assuntos
Arritmias Cardíacas/veterinária , Doenças do Cão/diagnóstico , Gastrite/veterinária , Infecções por Helicobacter/veterinária , Miocardite/veterinária , Animais , Antibacterianos/uso terapêutico , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/terapia , Diagnóstico Diferencial , Doenças do Cão/terapia , Cães , Cardioversão Elétrica/métodos , Cardioversão Elétrica/veterinária , Eletrocardiografia/veterinária , Evolução Fatal , Gastrite/complicações , Gastrite/diagnóstico , Gastrite/terapia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/terapia , Masculino , Miocardite/complicações , Miocardite/diagnóstico , Miocardite/terapia , Recidiva
16.
Folia Morphol (Warsz) ; 66(1): 33-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17533592

RESUMO

The heart is a muscular organ supported by collagenous tissue. The collagenous tissue is condensed in certain areas to form a supporting framework, often called the fibrous skeleton. The so-called tendon of the infundibulum has previously been described as part of this skeleton, but its structure and incidence remain ill defined. The tendon was initially described as a strip of fibrous tissue running between the aortic root and the pulmonary trunk. Since information on its structure is vague, we sought to evaluate its existence in 100 formalin-fixed adult human hearts obtained from subjects ranging in age from 22 to 86 years, in 20 hearts from infants and children aged from 2 months to 6 years at the time of their death and in 10 cattle hearts. We used classical macroscopic anatomical techniques to demonstrate all the possible connections between the sinuses of the aorta and the pulmonary trunk. We then supplemented the macroscopic techniques with serial transverse histological sections taken through the vascular roots, staining the sections with the haematoxylin-eosin, van Gieson, Masson trichrome and orcein staining methods. Fascial bands surrounded by connective tissue were observed in all hearts. In 80 adult hearts and in 16 neonatal hearts we found fascial bands or strips, which connected the aortic and pulmonary roots. Only in two hearts, however, were we able to identify tendon-like structures, and histology revealed that these were formed by tightly packed collagen fibres intermingled with fat, most likely due to advanced age. Thus in those cases where a "tendon" was present it was no more than condensed fascial bands joining together the apposing sinuses of the arterial trunks. In our opinion, therefore, accounts in the literature describing the "tendon of the infundibulum" as a tendinous structure connecting the aortic and pulmonary roots do not accurately represent this anatomical structure.


Assuntos
Tecido Conjuntivo/anatomia & histologia , Coração/anatomia & histologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Aorta/anatomia & histologia , Bovinos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Pericárdio/anatomia & histologia , Artéria Pulmonar/anatomia & histologia , Terminologia como Assunto
17.
J Vet Cardiol ; 19(1): 35-43, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27919727

RESUMO

OBJECTIVES: To describe signalment, clinical characteristics, diagnostic, treatment, and outcome data in a large case series of cats with patent ductus arteriosus (PDA). ANIMALS: Fifty cats with confirmed PDA. METHODS: Retrospective review of medical records from five referral veterinary hospitals for cats with PDA between 2000 and 2015. Cats were included if a PDA was visualized echocardiographically, during surgery, or on post-mortem examination. RESULTS: Median age at presentation was 6 months (range: 36 days-9.7 years; n = 50), and sex distribution was approximately equal (27 male, 23 female). Most cats did not have clinical signs (70.2%; 33/47) at the time of presentation. Murmurs were classified as continuous (55%; 22/40) or systolic (45%; 18/40). Echocardiography confirmed left-to-right shunting in 33 cats (82.5%; 33/40) and right-to-left shunting in 7 (17.5%; 7/40). Concurrent cardiac anomalies were identified in 54.5% (18/33) and pulmonary hypertension in 45.7% (16/35). Closure was pursued in 68% (34/50), and complications associated with the procedure occurred in 14.7% (5/34) of cats, including one intraoperative mortality. Long-term follow up was available in 80% (40/50) of cats. CONCLUSIONS: Cats with PDA often do not display clinical signs and may not have the characteristic physical examination findings typical of PDA in dogs. An increased prevalence of concurrent cardiac anomalies and pulmonary hypertension were found relative to previous reports. Thoracic radiographs and echocardiogram may provide the most comprehensive information for making a diagnosis and treatment recommendations. PDA closure was associated with a favorable long-term outcome in cats included in this study.


Assuntos
Doenças do Gato/fisiopatologia , Permeabilidade do Canal Arterial/veterinária , Animais , Doenças do Gato/diagnóstico por imagem , Doenças do Gato/terapia , Gatos , Permeabilidade do Canal Arterial/diagnóstico por imagem , Permeabilidade do Canal Arterial/fisiopatologia , Permeabilidade do Canal Arterial/terapia , Ecocardiografia/veterinária , Feminino , Hipertensão Pulmonar/veterinária , Masculino , Radiografia Torácica/veterinária , Estudos Retrospectivos , Análise de Sobrevida , Fístula Vascular/veterinária
18.
Structure ; 5(3): 359-70, 1997 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-9083105

RESUMO

BACKGROUND: Fibronectin is an extracellular matrix glycoprotein involved in cell adhesion and migration events in a range of important physiological processes. Aberrant adhesion of cells to the matrix may contribute to the breakdown of normal tissue function associated with various diseases. The adhesive properties of fibronectin may be mediated by its interaction with collagen, the most abundant extracellular matrix protein. The collagen-binding activity of fibronectin has been localized to a 42 kDa proteolytic fragment on the basis of this fragment's affinity for denatured collagen (gelatin). This gelatin-binding domain contains the only type 2 (F2) modules found in the protein. The F2 modules of the matrix metalloproteinases MMP2 and MMP9 are responsible for the affinity of these proteins for gelatin. Knowledge of the structure of fibronectin will provide insights into its interactions with other proteins, and will contribute to our understanding of the structure and function of the extracellular matrix, in both normal and disease-altered tissues. RESULTS: We have determined the solution structure of the first F2 (1F2) module from human fibronectin by two-dimensional NMR spectroscopy. The tertiary structure of the 1F2 module is similar to that of a shorter F2 module, PDC-109b, from the bovine seminal plasma protein PDC-109. The 1F2 module has two double-stranded antiparallel beta sheets oriented approximately perpendicular to each other, and enclosing a cluster of highly conserved aromatic residues, five of which form a solvent-exposed hydrophobic surface. The N-terminal extension in 1F2 brings the N and C termini of the module into close proximity. CONCLUSIONS: The close proximity of the N and C termini in 1F2 allows for interactions between non-contiguous modules in the gelatin-binding domain. Thus, instead of forming an extended, linear chain of modules, the domain may have a more compact, globular structure. A pocket in the module's solvent-exposed hydrophobic surface may bind nonpolar residues in the putative fibronectin-binding site of the extracellular matrix component type I collagen.


Assuntos
Colágeno/metabolismo , Fibronectinas/química , Conformação Proteica , Sequência de Aminoácidos , Animais , Sítios de Ligação , Bovinos , Adesão Celular , Matriz Extracelular/química , Fibronectinas/genética , Gelatina/metabolismo , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Ligação Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/química , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
19.
J Vet Cardiol ; 18(3): 265-270, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27025569

RESUMO

A 6-month-old Beagle with tetralogy of Fallot underwent balloon valvuloplasty of the pulmonary valve. Balloon valvuloplasty was successful and resulted in palliation of clinical signs and an improved quality of life for approximately 9 months. After 9 months, the dog became symptomatic and a modified Blalock-Taussig shunt procedure was successfully performed. Based on this report, balloon valvuloplasty in dogs with tetralogy of Fallot appears to be a feasible technique that may result in improvement of clinical signs. In addition, it may allow for the delay of the more invasive surgical palliation and provide time for weight gain and development of the pulmonary vascular bed for greater ease of surgical shunt creation.


Assuntos
Valvuloplastia com Balão/veterinária , Doenças do Cão/terapia , Estenose da Valva Pulmonar/terapia , Tetralogia de Fallot/terapia , Animais , Dilatação , Cães , Feminino , Cuidados Paliativos , Estenose da Valva Pulmonar/etiologia , Tetralogia de Fallot/complicações
20.
Prog Biophys Mol Biol ; 76(3): 131-73, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11709204

RESUMO

There is increasing evidence that intrinsically unstructured proteins or protein domains have important biological functions. These types of proteins may be productively analyzed using polymer theory developed to predict global physical properties of polymers. In these theories molecular detail is "coarse grained" out of the models, and replaced with a small number of parameters that characterize the polymer. This reduction in complexity allows extremely large systems to be studied. In the case of simulations, the time scales accessible also increase significantly. Here we discuss the application of polymer theory to unstructured proteins, and consider how to classify proteins within a polymer framework. We then review polymer theory that is relevant to predicting functionally important properties, such as radius of gyration, height of a polymer brush and force required to compress a polymer brush.


Assuntos
Proteínas/química , Proteínas/fisiologia , Biopolímeros/classificação , Eletroquímica , Conformação Proteica , Propriedades de Superfície
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