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1.
Ann Oncol ; 34(10): 885-898, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37597578

RESUMO

BACKGROUND: HER2 mutations are targetable alterations in patients with hormone receptor-positive (HR+) metastatic breast cancer (MBC). In the SUMMIT basket study, patients with HER2-mutant MBC received neratinib monotherapy, neratinib + fulvestrant, or neratinib + fulvestrant + trastuzumab (N + F + T). We report results from 71 patients with HR+, HER2-mutant MBC, including 21 (seven in each arm) from a randomized substudy of fulvestrant versus fulvestrant + trastuzumab (F + T) versus N + F + T. PATIENTS AND METHODS: Patients with HR+ HER2-negative MBC with activating HER2 mutation(s) and prior cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) therapy received N + F + T (oral neratinib 240 mg/day with loperamide prophylaxis, intramuscular fulvestrant 500 mg on days 1, 15, and 29 of cycle 1 then q4w, intravenous trastuzumab 8 mg/kg then 6 mg/kg q3w) or F + T or fulvestrant alone. Those whose disease progressed on F + T or fulvestrant could cross-over to N + F + T. Efficacy endpoints included investigator-assessed objective response rate (ORR), clinical benefit rate (RECIST v1.1), duration of response, and progression-free survival (PFS). Plasma and/or formalin-fixed paraffin-embedded tissue samples were collected at baseline; plasma was collected during and at end of treatment. Extracted DNA was analyzed by next-generation sequencing. RESULTS: ORR for 57 N + F + T-treated patients was 39% [95% confidence interval (CI) 26% to 52%); median PFS was 8.3 months (95% CI 6.0-15.1 months). No responses occurred in fulvestrant- or F + T-treated patients; responses in patients crossing over to N + F + T supported the requirement for neratinib in the triplet. Responses were observed in patients with ductal and lobular histology, 1 or ≥1 HER2 mutations, and co-occurring HER3 mutations. Longitudinal circulating tumor DNA sequencing revealed acquisition of additional HER2 alterations, and mutations in genes including PIK3CA, enabling further precision targeting and possible re-response. CONCLUSIONS: The benefit of N + F + T for HR+ HER2-mutant MBC after progression on CDK4/6is is clinically meaningful and, based on this study, N + F + T has been included in the National Comprehensive Cancer Network treatment guidelines. SUMMIT has improved our understanding of the translational implications of targeting HER2 mutations with neratinib-based therapy.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Fulvestranto , Receptor ErbB-2 , Trastuzumab
2.
J Nutr Health Aging ; 25(10): 1205-1216, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34866147

RESUMO

OBJECTIVES: To investigate frailty prevalence, cross-sectional associations, predictive validity, concurrent validity, and cross-cultural adaptations of the FRAIL-NH scale. DESIGN: Systematic review. SETTING AND PARTICIPANTS: Frail residents living in nursing homes. METHODS: MEDLINE, EMBASE, CINAHL, and Cochrane Library were searched from January 2015 to June 2021 for primary studies that used the FRAIL-NH scale, irrespective of study designs and publication language. RESULTS: Overall, 40 studies conducted across 20 countries utilized the FRAIL-NH scale; majority in Australia (n=14), followed by China (n=6), United States (n=3), and Spain (n=3). The scale has been translated and back-translated into Brazilian Portuguese, Chinese, and Japanese. Various cut-offs have been used, with ≥2 and ≥6 being the most common cut-offs for frail and most frail, respectively. When defined using these cut-offs, frailty prevalence varied from 15.1-79.5% (frail) to 28.5-75.0% (most frail). FRAIL-NH predicted falls (n=2), hospitalization or length of stay (n=4), functional or cognitive decline (n=4), and mortality (n=9) over a median follow-up of 12 months. FRAIL-NH has been compared to 16 other scales, and was correlated with Fried's phenotype (FP), Frailty Index (FI), and FI-Lab. Four studies reported fair-to-moderate agreements between FRAIL-NH and FI, FP, and the Comprehensive Geriatric Assessment. Ten studies assessed the sensitivity and specificity of different FRAIL-NH cut-offs, with ≥8 having the highest sensitivity (94.1%) and specificity (82.8%) for classifying residents as frail based on FI, while two studies reported an optimal cut-off of ≥2 based on FI and FP, respectively. CONCLUSION: In seven years, the FRAIL-NH scale has been applied in 20 countries and adapted into three languages. Despite being applied with a range of cut-offs, FRAIL-NH was associated with higher care needs and demonstrated good agreement with other well-established but more complex scales. FRAIL-NH was predictive of adverse outcomes across different settings, highlighting its value in guiding care for frail residents in nursing homes.


Assuntos
Fragilidade , Idoso , Estudos Transversais , Idoso Fragilizado , Fragilidade/diagnóstico , Avaliação Geriátrica , Humanos , Casas de Saúde
3.
J Frailty Aging ; 10(4): 343-349, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34549249

RESUMO

BACKGROUND: The risks of intensive blood glucose lowering may outweigh the benefits in vulnerable older people. OBJECTIVES: Our primary aim was to determine whether age, frailty, or dementia predict discharge treatment types for patients with type 2 diabetes (T2D) and related complications. Secondly, we aimed to determine the association between prior hypoglycemia and discharge treatment types. DESIGN, SETTING AND PARTICIPANTS: We conducted a cohort study involving 3,067 patients aged 65-99 years with T2D and related complications, discharged from Melbourne's Eastern Health Hospital Network between 2012 and 2016. MEASUREMENTS: Multinomial logistic regression was used to estimate odds ratios (ORs) with 95% confidence intervals (CI) for the association between age, frailty, dementia and hypoglycemia, and being prescribed insulin-only, non-insulin glucose-lowering drugs (GLDs) or combined insulin and non-insulin GLDs compared to no GLD. International Classification of Diseases-10 codes were used to identify dementia status and prior hypoglycemia; frailty was quantified using the Hospital Frailty Risk Score. RESULTS: Insulin-only, non-insulin GLDs, combined insulin and non-insulin GLDs, and no GLDs were prescribed to 19%, 39%, 20%, and 23% of patients, respectively. Patients >80 years were less likely than patients aged 65-80 to be prescribed any of the GLD therapies, (eg. non-insulin GLDs [OR 0.67; 95%CI 0.55-0.82]), compared to no GLD. Similarly, high vs. low frailty scores were associated with not being prescribed any of the three GLD therapies, (eg. non-insulin GLDs [OR 0.63; 95%CI 0.45-0.87]). However, dementia was not associated with discharge prescribing of GLD therapies. Patients with a hypoglycemia-related admission were more likely than those not hospitalized with hypoglycemia to receive insulin-only (OR 4.28; 95%CI 2.89-6.31). CONCLUSIONS: Clinicians consider age and frailty when tailoring diabetes treatment regimens for patients discharged from hospital with T2D and related complications. There is scope to optimize prescribing for patients with dementia and for those admitted with hypoglycemia.


Assuntos
Demência , Diabetes Mellitus Tipo 2 , Fragilidade , Idoso , Estudos de Coortes , Demência/tratamento farmacológico , Demência/epidemiologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Fragilidade/epidemiologia , Hospitais , Humanos , Alta do Paciente
4.
Sci Rep ; 10(1): 9836, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32555309

RESUMO

A cross-linking technique involving application of Bacteriochlorophyll Derivative WST-11 mixed with dextran (WST-D) to the epithelium-debrided cornea and illumination with Near Infrared (NIR), has been identified as a promising therapy for stiffening pathologically weakened corneas. To investigate its effect on corneal collagen architecture, x-ray scattering and electron microscopy data were collected from paired WST-D/NIR treated and untreated rabbit corneas. The treated eye received 2.5 mg/mL WST-D and was illuminated by a NIR diode laser (755 nm, 10 mW/cm2). An increase in corneal thickness (caused by corneal oedema) occurred at 1-day post-treatment but resolved in the majority of cases within 4 days. The epithelium was fully healed after 6-8 days. X-ray scattering revealed no difference in average collagen interfibrillar spacing, fibril diameter, D-periodicity or intermolecular spacing between treated and untreated specimens. Similarly, electron microscopy images of the anterior and posterior stroma in healed WST-D/NIR corneas and untreated controls revealed no obvious differences in collagen organisation or fibril diameter. As the size and organisation of stromal collagen is closely associated with the optical properties of the cornea, the absence of any large-scale changes following treatment confirms the potential of WST-D/NIR therapy as a means of safely stiffening the cornea.


Assuntos
Bacterioclorofilas/farmacologia , Substância Própria/efeitos dos fármacos , Substância Própria/efeitos da radiação , Raios Infravermelhos , Animais , Colágeno/metabolismo , Substância Própria/metabolismo , Substância Própria/ultraestrutura , Lasers , Microscopia Eletrônica , Coelhos
5.
Diabet Med ; 37(8): 1367-1373, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31557346

RESUMO

AIM: To determine the patterns and predictors of pharmacological treatment initiation for type 2 diabetes and whether treatment initiation is consistent with Australian clinical practice guidelines that recommend metformin monotherapy. METHODS: Individuals aged 40-99 years initiating a non-insulin type 2 diabetes medication between July 2013 and February 2018 were identified from a 10% random national sample of pharmacy dispensing data. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the predictors of initiating sulfonylurea monotherapy, non-guideline monotherapy and combination therapy compared with metformin monotherapy. Predictors included age, sex, initiation year and comorbidities determined using the Rx-Risk comorbidity index. RESULTS: Of the 47 860 initiators, [47% women, mean age 60.7 (sd 12.1) years], 85.8%, 4.6%, 1.9% and 7.7% received metformin monotherapy, sulfonylurea monotherapy, non-guideline monotherapy and combination therapy, respectively. Increasing age was associated with increasing odds of initiating sulfonylurea monotherapy and non-guideline monotherapy. Combination therapy initiation was less likely in women (OR 0.74, 95% CI 0.69-0.79) and people with more comorbidities (e.g. OR 0.36, 95% CI 0.29-0.44 for seven or more comorbidities vs. no comorbidities) but more likely in congestive heart failure (OR 1.42, 95% CI 1.22-1.65), cerebrovascular disease (OR 1.50, 95% CI 1.32-1.69) and dyslipidaemia (OR 1.29, 95% CI 1.19-1.40). CONCLUSION: Treatment initiation in Australia is largely consistent with clinical practice guidelines, with 86% of individuals initiating metformin monotherapy. Initiation on combination therapy was more common in men and in those with fewer comorbidities.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Fidelidade a Diretrizes/estatística & dados numéricos , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Guias de Prática Clínica como Assunto , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Transtornos Cerebrovasculares/epidemiologia , Comorbidade , Diabetes Mellitus Tipo 2/epidemiologia , Quimioterapia Combinada , Dislipidemias/epidemiologia , Feminino , Insuficiência Cardíaca/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Compostos de Sulfonilureia/uso terapêutico
6.
Diabetes Res Clin Pract ; 158: 107909, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31697992

RESUMO

AIMS: To characterise the patterns of switching, adherence, and persistence among adults aged ≥18 years with diabetes prescribed dipeptidyl peptidase-4 inhibitors (DPP-4is) in Australia. METHODS: The analysis included 15,915 adults newly prescribed DPP-4is (sitagliptin = 9576; vildagliptin = 1130; saxagliptin = 1126; linagliptin = 3560; and alogliptin = 523). Multivariable logistic regression model was used to compare the non-adherence (proportion of days covered [PDC] <0.80) rates whereas Cox proportional hazards regression models were used to compare switching and non-persistence (≥90-day gap) among different DPP4-is over 12-months. RESULTS: Overall, 36.0% (5722/15,915) of DPP-4i users were non-adherent and 30.0% (4775/15,915) were non-persistent at 12-months. Compared to sitagliptin, vildagliptin, linagliptin, and alogliptin were not associated with higher non-adherence and non-persistence. However, saxagliptin was associated with a higher likelihood of being non-adherent (odds ratio 1.41, 95% confidence interval [CI] 1.23-1.60) or non-persistent (hazard ratio 1.27, 95% CI 1.15-1.42) compared to sitagliptin. Just 3.2% of people switched between different DPP-4is. Compared to sitagliptin, people initiated on vildagliptin, saxagliptin, alogliptin, and linagliptin were more likely to switch. CONCLUSIONS: We found no significant differences in the adherence and persistence rates between alogliptin, vildagliptin or linagliptin and sitagliptin. However, saxagliptin was associated with higher non-adherence and non-persistence compared to sitagliptin. Switching was lowest amongst users of sitagliptin.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Hipoglicemiantes/uso terapêutico , Idoso , Estudos de Coortes , Inibidores da Dipeptidil Peptidase IV/farmacologia , Feminino , Humanos , Hipoglicemiantes/farmacologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
7.
Public Health ; 173: 120-125, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31271966

RESUMO

OBJECTIVES: The objective of this study is to explore facilitating factors for collaboration at hackathons, intensive events bringing together data scientists ('hackers') with experts in particular subject areas. STUDY DESIGN: This is a qualitative study. METHODS: Semistructured interviews were conducted with organisers before and after the event. The initial exploratory interviews influenced the content of questionnaires which were distributed to all participants asking about their motivations and experiences. Thematic analysis was used to explore key features of collaboration. RESULTS: Facilitating factors were clustered under the themes of preparation (the right amount of pre-event information, methods to maximise attendance and identification of suitable challenges), participants (enough people to progress and a mixture of skills and experience), working together (mutual understanding of the aim, getting the best out of each other, overcoming challenges together, effective facilitation and an enjoyable and valuable experience) and follow-up (recognised process for feedback and support for the development of prototypes). CONCLUSIONS: The findings of the study provide insight into fostering collaboration in this context and provide evidence that may be used to tailor future events for the effective delivery of technological and marketing-based solutions to public health challenges. Hackathons provide a methodological advance with potential for broad public health application.


Assuntos
Comportamento Cooperativo , Ciência de Dados , Saúde Pública , Humanos , Pesquisa Qualitativa
8.
Neuropathol Appl Neurobiol ; 45(3): 195-215, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30298527

RESUMO

Inflammation and neurodegeneration are key features of many chronic neurological diseases, yet the causative mechanisms underlying these processes are poorly understood. There has been mounting interest in the role of the human microbiome in modulating the inflammatory milieu of the central nervous system (CNS) in health and disease. To date, most research has focussed on a gut-brain axis, with other mucosal surfaces being relatively neglected. We herein take the novel approach of comprehensively reviewing the roles of the microbiome across several key mucosal interfaces - the nose, mouth, lung and gut - in health and in Parkinson's disease (PD), Alzheimer's disease (AD) and multiple sclerosis (MS). This review systematically appraises the anatomical and microbiological landscape of each mucosal surface in health and disease before considering relevant mechanisms that may influence the initiation and progression of PD, AD and MS. The cumulative effects of dysbiosis from the nose to the gut may contribute significantly to neurological disease through a wide variety of mechanisms, including direct translocation of bacteria and their products, and modulation of systemic or CNS-specific immunity. This remains an understudied and exciting area for future research and may lead to the development of therapeutic targets for chronic neurological disease.


Assuntos
Doença de Alzheimer/microbiologia , Disbiose/microbiologia , Inflamação/microbiologia , Intestinos/microbiologia , Pulmão/microbiologia , Microbiota , Boca/microbiologia , Esclerose Múltipla/microbiologia , Cavidade Nasal/microbiologia , Transtornos do Olfato/microbiologia , Doença de Parkinson/microbiologia , Doença de Alzheimer/complicações , Humanos , Esclerose Múltipla/complicações , Transtornos do Olfato/etiologia , Doença de Parkinson/complicações
9.
Sci Rep ; 8(1): 6709, 2018 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-29712937

RESUMO

Human deep space and planetary travel is limited by uncertainties regarding the health risks associated with exposure to galactic cosmic radiation (GCR), and in particular the high linear energy transfer (LET), heavy ion component. Here we assessed the impact of two high-LET ions 56Fe and 28Si, and low-LET X rays on genome-wide methylation patterns in human bronchial epithelial cells. We found that all three radiation types induced rapid and stable changes in DNA methylation but at distinct subsets of CpG sites affecting different chromatin compartments. The 56Fe ions induced mostly hypermethylation, and primarily affected sites in open chromatin regions including enhancers, promoters and the edges ("shores") of CpG islands. The 28Si ion-exposure had mixed effects, inducing both hyper and hypomethylation and affecting sites in more repressed heterochromatic environments, whereas X rays induced mostly hypomethylation, primarily at sites in gene bodies and intergenic regions. Significantly, the methylation status of 56Fe ion sensitive sites, but not those affected by X ray or 28Si ions, discriminated tumor from normal tissue for human lung adenocarcinomas and squamous cell carcinomas. Thus, high-LET radiation exposure leaves a lasting imprint on the epigenome, and affects sites relevant to human lung cancer. These methylation signatures may prove useful in monitoring the cumulative biological impact and associated cancer risks encountered by astronauts in deep space.


Assuntos
Radiação Cósmica/efeitos adversos , Metilação de DNA/efeitos da radiação , Epigenômica , Neoplasias Pulmonares/genética , Astronautas , Brônquios/patologia , Brônquios/efeitos da radiação , Metilação de DNA/genética , Células Epiteliais/efeitos da radiação , Humanos , Transferência Linear de Energia , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/patologia , Voo Espacial , Raios X
10.
Acta Biomater ; 65: 216-225, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29128531

RESUMO

Fibrillar collagen in the human cornea is integral to its function as a transparent lens of precise curvature, and its arrangement is now well-characterised in the literature. While there has been considerable effort to incorporate fibrillar architecture into mechanical models of the cornea, the mechanical response of corneal collagen to small applied loads is not well understood. In this study the fibrillar and molecular response to tensile load was quantified using small and wide angle X-ray scattering (SAXS/WAXS), and digital image correlation (DIC) photography was used to calculate the local strain field that gave rise to the hierarchical changes. A molecular scattering model was used to calculate the tropocollagen tilt relative to the fibril axis and changes associated with applied strain. Changes were measured in the D-period, molecular tilt and the orientation and spacing of the fibrillar and molecular networks. These measurements were summarised into hierarchical deformation mechanisms, which were found to contribute at varying strains. The change in molecular tilt is indicative of a sub-fibrillar "spring-like" deformation mechanism, which was found to account for most of the applied strain under physiological and near-physiological loads. This deformation mechanism may play an important functional role in tissues rich in fibrils of high helical tilt, such as skin and cartilage. STATEMENT OF SIGNIFICANCE: Collagen is the primary mediator of soft tissue biomechanics, and variations in its hierarchical structure convey the varying amounts of structural support necessary for organs to function normally. Here we have examined the structural response of corneal collagen to tensile load using X-rays to probe hierarchies ranging from molecular to fibrillar. We found a previously unreported deformation mechanism whereby molecules, which are helically arranged relative to the axis of their fibril, change in tilt akin to the manner in which a spring stretches. This "spring-like" mechanism accounts for a significant portion of the applied deformation at low strains (<3%). These findings will inform the future design of collagen-based artificial corneas being developed to address world-wide shortages of corneal donor tissue.


Assuntos
Córnea/metabolismo , Colágenos Fibrilares/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Humanos , Pessoa de Meia-Idade , Fotografação , Espalhamento de Radiação , Resistência à Tração , Difração de Raios X , Adulto Jovem
11.
Am J Physiol Heart Circ Physiol ; 311(6): H1560-H1568, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27663767

RESUMO

Vascular diseases such as diabetes and hypertension cause changes to the vasculature that can lead to vessel stiffening and the loss of vasoactivity. The microstructural bases of these changes are not presently fully understood. We present a new methodology for stain-free visualization, at a microscopic scale, of the morphology of the main passive components of the walls of unfixed resistance arteries and their response to changes in transmural pressure. Human resistance arteries were dissected from subcutaneous fat biopsies, mounted on a perfusion myograph, and imaged at varying transmural pressures using a multimodal nonlinear microscope. High-resolution three-dimensional images of elastic fibers, collagen, and cell nuclei were constructed. The honeycomb structure of the elastic fibers comprising the internal elastic layer became visible at a transmural pressure of 30 mmHg. The adventitia, comprising wavy collagen fibers punctuated by straight elastic fibers, thinned under pressure as the collagen network straightened and pulled taut. Quantitative measurements of fiber orientation were made as a function of pressure. A multilayer analytical model was used to calculate the stiffness and stress in each layer. The adventitia was calculated to be up to 10 times as stiff as the media and experienced up to 8 times the stress, depending on lumen diameter. This work reveals that pressure-induced reorganization of fibrous proteins gives rise to very high local strain fields and highlights the unique mechanical roles of both fibrous networks. It thereby provides a basis for understanding the micromechanical significance of structural changes that occur with age and disease.


Assuntos
Túnica Adventícia/ultraestrutura , Artérias/ultraestrutura , Núcleo Celular/ultraestrutura , Colágeno/ultraestrutura , Tecido Elástico/ultraestrutura , Resistência Vascular , Adulto , Artérias/fisiologia , Fenômenos Biomecânicos , Feminino , Voluntários Saudáveis , Humanos , Imageamento Tridimensional , Masculino , Microscopia , Imagem Multimodal , Miografia , Pressão , Gordura Subcutânea/irrigação sanguínea , Adulto Jovem
12.
Osteoarthritis Cartilage ; 23(10): 1806-16, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26050867

RESUMO

OBJECTIVE: To investigate the relationships between the unique mechanical and structural properties of the superficial zone of articular cartilage on the microscopic scale. DESIGN: Fresh unstained equine metacarpophalangeal cartilage samples were mounted on tensile and compressive loading rigs on the stage of a multiphoton microscope. Sequential image stacks were acquired under incremental loads together with simultaneous measurements of the applied stress and strain. Second harmonic generation was used to visualise the collagen fibre network, while two photon fluorescence was used to visualise elastin fibres and cells. The changes visualised by each modality were tracked between successive loads. RESULTS: The deformation of the cartilage matrix was heterogeneous on the microscopic length scale. This was evident from local strain maps, which showed shearing between different regions of collagen under tensile strain, corrugations in the articular surface at higher tensile strains and a non-uniform distribution of compressive strain in the axial direction. Chondrocytes elongated and rotated under tensile strain and were compressed in the axial direction under compressive load. The magnitude of deformation varied between cells, indicating differences in either load transmission through the matrix or the mechanical properties of individual cells. Under tensile loading the reorganisation of the elastin network differed from a homogeneous elastic response, indicating that it forms a functional structure. CONCLUSIONS: This study highlights the complexity of superficial zone mechanics and demonstrates that the response of the collagen matrix, elastin fibres and chondrocytes are all heterogeneous on the microscopic scale.


Assuntos
Cartilagem Articular/fisiologia , Condrócitos/fisiologia , Matriz Extracelular/fisiologia , Articulação Metacarpofalângica , Estresse Mecânico , Suporte de Carga/fisiologia , Animais , Fenômenos Biomecânicos , Colágeno/fisiologia , Força Compressiva , Elastina/fisiologia , Cavalos , Microscopia de Fluorescência por Excitação Multifotônica , Resistência à Tração
14.
Acta Biomater ; 10(6): 2574-81, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24525036

RESUMO

Articular cartilage (AC) is a highly anisotropic biomaterial, and its complex mechanical properties have been a topic of intense investigation for over 60 years. Recent advances in the field of nonlinear optics allow the individual constituents of AC to be imaged in living tissue without the need for exogenous contrast agents. Combining mechanical testing with nonlinear microscopy provides a wealth of information about microscopic responses to load. This work investigates the inhomogeneous distribution of strain in loaded AC by tracking the movement and morphological changes of individual chondrocytes using point pattern matching and Bayesian modeling. This information can be used to inform models of mechanotransduction and pathogenesis, and is readily extendable to various other connective tissues.


Assuntos
Cartilagem Articular/fisiologia , Microscopia/métodos , Resistência à Tração , Animais , Fenômenos Biomecânicos , Cavalos
15.
Int J Clin Pract ; 68(2): 236-44, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24372715

RESUMO

BACKGROUND: Community treatment orders (CTOs) are legal orders which require individuals with mental illness to accept treatment in the community. Previous studies report that long-acting injectable (LAI) antipsychotics are associated with CTOs, however, little is known about the specific treatment plans prescribed in CTOs. The objective of this study was to describe the patterns of psychotropic drugs prescribed to individuals issued a CTO, focusing on LAI antipsychotics, antipsychotic polypharmacy and high-dose antipsychotics. METHODS: This was a retrospective cross-sectional study of 378 individuals randomly selected from a sample of 1317 individuals with a CTO expiry date up to and including 30 April 2010, taken from all 2856 individuals issued a CTO by the New South Wales Mental Health Review Tribunal, Australia, in 2009. De-identified information relating to individuals' treatment plans, demographic and clinical details were systematically extracted. RESULTS: A total of 377 (99.7%) individuals were prescribed at least one antipsychotic. Of these, 310 (82%) were prescribed a LAI antipsychotic, either alone (45%), or in combination with, an oral antipsychotic (37%). Risperidone was the most prevalent antipsychotic, prescribed to 164 (43%) individuals. Antipsychotic polypharmacy was prescribed to 121 (32%) individuals and between 20% and 27% of individuals were prescribed high-dose antipsychotics. Antipsychotic polypharmacy accounted for 74-80% of individuals prescribed high-dose antipsychotics. CONCLUSIONS: The results from this study confirm that LAI antipsychotics are commonly prescribed in CTOs. Antipsychotic polypharmacy was also common, and accounted for the majority of individuals prescribed high-dose antipsychotics. Further research is needed to determine the potential outcomes and implications of the patterns observed.


Assuntos
Antipsicóticos/administração & dosagem , Transtornos Mentais/tratamento farmacológico , Administração Oral , Adulto , Internação Compulsória de Doente Mental/estatística & dados numéricos , Serviços Comunitários de Saúde Mental/estatística & dados numéricos , Estudos Transversais , Preparações de Ação Retardada , Quimioterapia Combinada , Feminino , Humanos , Masculino , New South Wales , Medicamentos sob Prescrição/administração & dosagem , Estudos Retrospectivos
16.
Anim Genet ; 44(2): 169-77, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22686255

RESUMO

Progressive retinal atrophy (PRA) in dogs is characterised by the degeneration of the photoreceptor cells of the retina, resulting in vision loss and eventually complete blindness. The condition affects more than 100 dog breeds and is known to be genetically heterogeneous between breeds. Around 14 mutations have now been identified that are associated with PRA in around 49 breeds, but for the majority of breeds the mutation(s) responsible have yet to be identified. Using genome-wide association with 16 Gordon Setter PRA cases and 22 controls, we identified a novel PRA locus, termed rod-cone degeneration 4 (rcd4), on CFA17 (Praw  = 2.22 × 10(-8) , Pgenome  = 2.00 × 10(-5) ), where a 3.2-Mb region was homozygous within cases. A frameshift mutation was identified in C2orf71, a gene located within this region. This variant was homozygous in 19 of 21 PRA cases and was at a frequency of approximately 0.37 in the Gordon Setter population. Approximately 10% of cases in our study (2 of 21) are not associated with this C2orf71 mutation, indicating that PRA in this breed is genetically heterogeneous and caused by at least two mutations. This variant is also present in a number of Irish Setter dogs with PRA and has an estimated allele frequency of 0.26 in the breed. The function of C2orf71 remains unknown, but it is important for retinal development and function and has previously been associated with autosomal recessive retinitis pigmentosa in humans.


Assuntos
Doenças do Cão/genética , Proteínas do Olho/genética , Mutação da Fase de Leitura/genética , Predisposição Genética para Doença/genética , Degeneração Retiniana/veterinária , Animais , Sequência de Bases , Primers do DNA/genética , Cães , Frequência do Gene , Loci Gênicos/genética , Estudo de Associação Genômica Ampla/veterinária , Dados de Sequência Molecular , Degeneração Retiniana/genética , Análise de Sequência de DNA/veterinária , Especificidade da Espécie
17.
Vet Pathol ; 49(5): 852-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21753036

RESUMO

A hereditary cerebellar degenerative disorder has emerged in Scottish Terriers. The aims of this study were to describe and quantify polyglucosan body accumulation and quantify Purkinje neurons in the cerebellum of affected and control dogs. The brains of 6 affected Scottish Terriers ranging in age from 8 to 15 years and 8 age-matched control dogs were examined histopathologically. Counts of Purkinje neurons and polyglucosan bodies were performed in control and affected dogs on cerebellar sections stained with periodic acid-Schiff. Affected dogs showed a significant loss of Purkinje neurons compared with control dogs (vermis: P < .0001; hemisphere: P = .0104). The degeneration was significantly more pronounced dorsally than ventrally (P < .0001). There were significantly more polyglucosan bodies in the ventral half of the vermis when compared with the dorsal half (P < .0001) in affected dogs. In addition, there were more polyglucosan bodies in the ventral half of the vermis in affected dogs than in control dogs (P = .0005). Polyglucosan bodies in all affected dogs stained positively with toluidine blue and alcian blue. Immunohistochemically, polyglucosan bodies in affected dogs were positive for neurofilament 200 kD and ubiquitin and negative for glial fibrillary acidic protein, synaptophysin, neurospecific enolase, vimentin, and S100; the bodies were negative for all antigens in control dogs. Ultrastructurally, polyglucosan bodies in 1 affected dog were non-membrane-bound, amorphous structures with a dense core. This study demonstrates significant Purkinje cell loss and increased polyglucosan bodies in the cerebellum of affected Scottish Terriers.


Assuntos
Cerebelo/patologia , Doenças do Cão/patologia , Glucanos/metabolismo , Degenerações Espinocerebelares/veterinária , Envelhecimento/patologia , Animais , Estudos de Casos e Controles , Córtex Cerebelar/metabolismo , Córtex Cerebelar/patologia , Córtex Cerebelar/ultraestrutura , Cerebelo/metabolismo , Cerebelo/ultraestrutura , Doenças do Cão/genética , Doenças do Cão/metabolismo , Cães , Feminino , Imuno-Histoquímica/veterinária , Corpos de Inclusão/metabolismo , Corpos de Inclusão/patologia , Corpos de Inclusão/ultraestrutura , Masculino , Microscopia Eletrônica de Transmissão/veterinária , Células de Purkinje/metabolismo , Células de Purkinje/patologia , Células de Purkinje/ultraestrutura , Degenerações Espinocerebelares/genética , Degenerações Espinocerebelares/metabolismo , Degenerações Espinocerebelares/patologia
18.
J Vet Intern Med ; 25(4): 890-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21777289

RESUMO

BACKGROUND: Tumors have heterogeneous properties, which could be explained by the existence of hierarchically and biologically distinct tumor cells such as tumor-initiating cells (TICs). This model is clinically important, as TICs are promising targets for cancer therapies. However, TICs in spontaneous B-cell lymphoma have not been conclusively identified. HYPOTHESIS/OBJECTIVES: Tumor cells with a progenitor phenotype exist in B-cell lymphoma, reflecting a hierarchical organization. ANIMALS: Twenty-eight client-owned dogs with previously untreated B-cell lymphoma and 6 healthy dogs. METHODS: This was a prospective study. Flow cytometry was used to identify lymphoid progenitor cells (LPCs) that coexpressed hematopoietic progenitor antigens CD34, CD117, and CD133, with lymphoid differentiation markers CD21 and/or CD22 in B-cell lymphoma. The polymerase chain reaction for antigen receptor rearrangements was used to analyze clonality and relatedness of tumor populations. A xenograft model with NOD/SCID/IL-2Rγ(-/-) mice was adapted to expand and serially transplant primary canine B-cell lymphoma. RESULTS: LPCs were expanded in lymph nodes from 28 dogs with B-cell lymphoma compared with 6 healthy dogs (P= .0022). LPCs contained a clonal antigen receptor gene rearrangement identical to that of the bulk of tumor cells. Canine B-cell lymphoma xenografts in recipient mice that maintained LPCs in the tumors were recurrently observed. CONCLUSIONS AND CLINICAL IMPORTANCE: These results suggest the presence of a hierarchy of tumor cells in B-cell lymphoma as has been demonstrated in other cancers. These findings have the potential to impact not only the understanding of lymphoma pathogenesis but also the development of lymphoma therapies by providing novel targets for therapy.


Assuntos
Doenças do Cão/patologia , Tecido Linfoide/patologia , Linfoma de Células B/patologia , Células-Tronco Neoplásicas/patologia , Antígeno AC133 , Animais , Antígenos CD/análise , Antígenos CD/imunologia , Antígenos CD34/análise , Antígenos CD34/imunologia , Estudos de Coortes , Modelos Animais de Doenças , Doenças do Cão/imunologia , Cães , Feminino , Citometria de Fluxo/veterinária , Glicoproteínas/análise , Glicoproteínas/imunologia , Imunofenotipagem/veterinária , Tecido Linfoide/citologia , Tecido Linfoide/imunologia , Linfoma de Células B/imunologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/imunologia , Peptídeos/análise , Peptídeos/imunologia , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-kit/análise , Proteínas Proto-Oncogênicas c-kit/imunologia , Organismos Livres de Patógenos Específicos , Estatísticas não Paramétricas , Transplante Heterólogo/veterinária
19.
J Vet Intern Med ; 24(3): 565-70, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20384950

RESUMO

BACKGROUND: Hereditary cerebellar degeneration is described in several dog breeds. This heterogeneous group of diseases causes cerebellar ataxia associated with cerebellar cortical degeneration. OBJECTIVE: To report the clinical and histopathological features, and describe the mode of inheritance of hereditary cerebellar degeneration in Scottish Terriers. ANIMALS: Sixty-two affected dogs recruited through the Scottish Terrier Club of America. MATERIALS AND METHODS: Prospective, observational study: Owners of affected dogs were contacted for a description of clinical signs, age of onset, and disease progression. Medical records, videotapes of gait, and brain imaging were evaluated. When possible, necropsy was performed and the brain examined histopathologically. Prevalence of the disease was estimated and a pedigree analysis was performed to determine mode of inheritance. RESULTS: Gait abnormalities were noted in the 1st year of life in 76% of dogs, and progressed slowly; only 1 of 27 dogs dead at time of writing was euthanized because of cerebellar degeneration. Clinical signs included wide based stance, dysmetria, intention tremor, and difficulty negotiating stairs and running. Cerebellar atrophy was detected on magnetic resonance imaging. On histopathological examination, there was segmental loss of Purkinje neurons, thinning of molecular and granular layers, and polyglucosan bodies in the molecular layer. Prevalence of disease was estimated at 1 in 1,335 American Kennel Club registered Scottish Terriers. Genetic analysis results are consistent with an autosomal recessive mode of inheritance. CONCLUSION AND CLINICAL IMPORTANCE: A hereditary cerebellar degenerative disorder with a relatively mild phenotype has emerged in the Scottish Terrier. Genetic studies are needed.


Assuntos
Doenças do Cão/genética , Predisposição Genética para Doença , Degenerações Espinocerebelares/veterinária , Animais , Cerebelo/patologia , Cães , Feminino , Masculino , Linhagem , Degenerações Espinocerebelares/genética
20.
Int J Soc Psychiatry ; 56(1): 3-14, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19861340

RESUMO

BACKGROUND: Healthcare professionals commonly exhibit negative attitudes toward people with mental disorders. Few international studies have sought to investigate the determinants of stigma. OBJECTIVE: To conduct an international comparison of pharmacy students' stigma towards people with schizophrenia, and to determine whether stigma is consistently associated with stereotypical attributes of people with schizophrenia. METHOD: Students (n = 649) at eight universities in Australia, Belgium, India, Finland, Estonia and Latvia completed a seven-item Social Distance Scale (SDS) and six items related to stereotypical attributes of people with schizophrenia. RESULTS: Mean SDS scores were 19.65 (+/- 3.97) in Australia, 19.61 (+/- 2.92) in Belgium, 18.75 (+/- 3.57) in India, 18.05 (+/- 3.12) in Finland, and 20.90 (+/- 4.04) in Estonia and Latvia. Unpredictability was most strongly associated with having a high social distance in Australia (beta = -1.285), the perception that people will never recover in India (beta = - 0.881), dangerousness in Finland (beta = -1.473) and the perception of being difficult to talk to in Estonia and Latvia (beta = -2.076). Unpredictability was associated with lower social distance in Belgium (beta = 0.839). CONCLUSION: The extent to which students held stigmatizing attitudes was similar in each country, however, the determinants of stigma were different. Pharmacy education may need to be tailored to address the determinants of stigma in each country.


Assuntos
Atitude do Pessoal de Saúde , Comparação Transcultural , Preconceito , Esquizofrenia/etnologia , Psicologia do Esquizofrênico , Estudantes de Farmácia/psicologia , Adulto , Austrália , Comportamento Perigoso , Europa (Continente) , Feminino , Humanos , Índia , Masculino , Distância Psicológica , Esquizofrenia/diagnóstico , Estereotipagem , Inquéritos e Questionários , Adulto Jovem
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