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1.
OTJR (Thorofare N J) ; 39(4): 189-196, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31046601

RESUMO

Participation refers to a state of health in which a person is able to fully engage in roles and life situations. Adults living with and beyond cancer often report persistent participation restrictions that affect their productivity and quality of life. The American Occupational Therapy Foundation convened a group of scientists from seven different disciplines in a Planning Grant Collective (PGC) to stimulate research to identify scalable ways to preserve and optimize participation among cancer survivors. Participants identified challenges, prioritized solutions, and generated novel research questions that move beyond symptom and impairment mitigation as outcomes to identify interventions that improve participation in roles and life situations. This article summarizes the PGC discussion and recommendations regarding three challenges: (a) the dynamic and multi-faceted nature of participation, (b) a need to integrate the concept of participation within the culture of oncology, and (c) identification of priority areas in which new lines of research regarding participation would be most impactful.


Assuntos
Sobreviventes de Câncer , Terapia Ocupacional , Atividades Cotidianas , Humanos , Qualidade de Vida , Projetos de Pesquisa
2.
Mol Biol Evol ; 33(8): 2002-15, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27189558

RESUMO

The Microsporidia are a major group of intracellular fungi and important parasites of animals including insects, fish, and immunocompromised humans. Microsporidian genomes have undergone extreme reductive evolution but there are major differences in genome size and structure within the group: some are prokaryote-like in size and organisation (<3 Mb of gene-dense sequence) while others have more typically eukaryotic genome architectures. To gain fine-scale, population-level insight into the evolutionary dynamics of these tiny eukaryotic genomes, we performed the broadest microsporidian population genomic study to date, sequencing geographically isolated strains of Spraguea, a marine microsporidian infecting goosefish worldwide. Our analysis revealed that population structure across the Atlantic Ocean is associated with a conserved difference in ploidy, with American and Canadian isolates sharing an ancestral whole genome duplication that was followed by widespread pseudogenisation and sorting-out of paralogue pairs. While past analyses have suggested de novo gene formation of microsporidian-specific genes, we found evidence for the origin of new genes from noncoding sequence since the divergence of these populations. Some of these genes experience selective constraint, suggesting the evolution of new functions and local host adaptation. Combining our data with published microsporidian genomes, we show that nucleotide composition across the phylum is shaped by a mutational bias favoring A and T nucleotides, which is opposed by an evolutionary force favoring an increase in genomic GC content. This study reveals ongoing dramatic reorganization of genome structure and the evolution of new gene functions in modern microsporidians despite extensive genomic streamlining in their common ancestor.


Assuntos
Microsporídios/genética , Evolução Biológica , Biologia Computacional , Evolução Molecular , Duplicação Gênica , Variação Genética , Genoma Fúngico , Genômica/métodos , Metagenômica , Filogenia , Filogeografia
3.
PLoS Genet ; 9(8): e1003676, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23990793

RESUMO

Microsporidia are obligate intracellular parasites with the smallest known eukaryotic genomes. Although they are increasingly recognized as economically and medically important parasites, the molecular basis of microsporidian pathogenicity is almost completely unknown and no genetic manipulation system is currently available. The fish-infecting microsporidian Spraguea lophii shows one of the most striking host cell manipulations known for these parasites, converting host nervous tissue into swollen spore factories known as xenomas. In order to investigate the basis of these interactions between microsporidian and host, we sequenced and analyzed the S. lophii genome. Although, like other microsporidia, S. lophii has lost many of the protein families typical of model eukaryotes, we identified a number of gene family expansions including a family of leucine-rich repeat proteins that may represent pathogenicity factors. Building on our comparative genomic analyses, we exploited the large numbers of spores that can be obtained from xenomas to identify potential effector proteins experimentally. We used complex-mix proteomics to identify proteins released by the parasite upon germination, resulting in the first experimental isolation of putative secreted effector proteins in a microsporidian. Many of these proteins are not related to characterized pathogenicity factors or indeed any other sequences from outside the Microsporidia. However, two of the secreted proteins are members of a family of RICIN B-lectin-like proteins broadly conserved across the phylum. These proteins form syntenic clusters arising from tandem duplications in several microsporidian genomes and may represent a novel family of conserved effector proteins. These computational and experimental analyses establish S. lophii as an attractive model system for understanding the evolution of host-parasite interactions in microsporidia and suggest an important role for lineage-specific innovations and fast evolving proteins in the evolution of the parasitic microsporidian lifecycle.


Assuntos
Apansporoblastina/genética , Evolução Molecular , Interações Hospedeiro-Parasita/genética , Proteínas/genética , Animais , Sequência de Bases , Peixes/genética , Peixes/parasitologia , Genoma , Proteínas de Repetições Ricas em Leucina , Filogenia , Proteômica , Esporos Fúngicos/genética
5.
Am J Physiol Heart Circ Physiol ; 293(3): H2004-6, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17513493

RESUMO

A technique for isolation of cardiac myocytes and collection of whole heart tissue from individual hearts of adult rats is described in this study. After excision of the apical half of the left ventricle (LV) and cauterization of the cut edge, aortas were cannulated and high-quality isolated cardiac myocytes were collected after collagenase perfusion of the basal portion. Myocyte dimensions from the basal portion of cauterized and noncauterized hearts from matching rats were identical. Additionally, myocyte dimensions from the basal and apical halves of the LV were compared with the use of whole heart-isolated myocyte preps. No regional differences between basal and apical LV myocyte size were found. Therefore, this cauterization method can be used to collect isolated myocytes from the basal half and whole heart tissue from the apical half, with each half being representative of the other with respect to myocyte dimensions.


Assuntos
Separação Celular/métodos , Miocárdio/citologia , Miócitos Cardíacos/citologia , Animais , Cauterização/métodos , Ventrículos do Coração/citologia , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
6.
Clin Chem ; 53(4): 711-6, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17272483

RESUMO

BACKGROUND: Circulating insulin concentration in serum or plasma provides important information for the estimation of insulin secretion and insulin resistance. Currently, lack of standardization of insulin assays hinders efforts to achieve consistent measures for treatment guidelines. METHODS: A Workgroup convened by the American Diabetes Association evaluated 12 different commercial insulin methods from 9 manufacturers. RESULTS: The within-assay CVs ranged from 3.7% to 39.0%, with 7 of 10 assays having a CV < or =10.6%. The among-assay CVs ranged from 12% to 66%, with a median value of 24%. A common insulin reference preparation did not change the among-assay CV and failed to improve harmonization of results among assays. Results from 6 of 10 assays agreed within the total error of 32% that is allowable based on biological variability criteria. Seven of 10 assays recovered insulin added to a serum pool within 15.5% of the expected concentration. In 9 of 10 methods, there was <2% cross-reactivity with intact human proinsulin, and 8 of 10 methods had <3% cross-reactivity with split (32, 33) proinsulin. For 9 of 10 assays, the cross-reactivity of des (64, 65) proinsulin exceeded 40%. Overall, most assays had acceptable imprecision and specificity for insulin. CONCLUSION: The discordance in test results for commercial insulin reagent sets is likely multifactorial and will require a continuing effort to understand the differences and achieve the desired consistency and harmonization among commercial immunoassays.


Assuntos
Diabetes Mellitus/diagnóstico , Insulina/sangue , Reações Cruzadas , Humanos , Imunoensaio/normas , Proinsulina/sangue
7.
Immunity ; 23(2): 115-26, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16111631

RESUMO

Type 1 diabetes (T1D) animal models such as the nonobese diabetic (NOD) mouse have improved our understanding of disease pathophysiology, but many candidate therapeutics identified therein have failed to prevent/cure human disease. We have performed a comprehensive evaluation of disease-modifying agents tested in the NOD mouse based on treatment timing, duration, study length, and efficacy. Interestingly, some popular tenets regarding NOD interventions were not confirmed: all treatments do not prevent disease, treatment dose and timing strongly influence efficacy, and several therapies have successfully treated overtly diabetic mice. The analysis provides a unique perspective on NOD interventions and suggests that the response of this model to therapeutic interventions can be a useful predictor of the human response as long as careful consideration is given to treatment dose, timing, and protocols; more thorough investigation of these parameters should improve clinical translation.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Modelos Animais de Doenças , Animais , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/fisiopatologia , Humanos , Camundongos , Camundongos Endogâmicos NOD
8.
Mol Cell Biochem ; 264(1-2): 183-91, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15544047

RESUMO

BACKGROUND: Idiopathic dilated cardiomyopathy (DCM), ventricular systolic dysfunction and chamber dilatation are accompanied by architectural remodeling, wall thinning and cardiac myocyte slippage. Recent work has demonstrated an association between collagen degradation and an increased expression of matrix metalloproteinases (MMPs). Accordingly, we have sought to correlate (a) collagen degradation with MMP elevations and, (b) assay the neutralizing potential of a known inhibitor of MMP, tetracycline on MMPs in DCM. METHODS: Assessment of LV volume and shape by 2-D echocardiography was performed. Light microscopic assessment of histopathology in picrosirius red stained biopsy samples of 11 DCM patients and six post-transplant patients was performed. Zymographic estimation of MMP activity and influence of tetracycline on MMP activity was assessed. RESULTS: Small amount of interstitial collagen was noted in the control group, whereas in the DCM hearts, chamber dilatation was associated with areas of scanty myocyte necrosis, islands of excess collagen, and focal areas of absent or scanty collagen with intact myocytes. In cardiomyopathic tissue, collagenase activity was markedly elevated at 63% compared with 8% in post-transplant tissue. Tetracycline at a concentration of 285+/-10 microM (IC50) inhibited collagenase activity by 50% in cardiomyopathic tissue. CONCLUSIONS: Areas of focal interstitial collagen accumulation were accompanied by collagen fiber lysis and increased collagenase activity in dilated cardiomyopathy. This enhanced collagenolytic activity found in endomyocardial biopsy tissue was inhibited by tetracycline. The non-antibiotic property of tetracycline may be of potential value in the prevention of ventricular dilatation in idiopathic dilated cardiomyopathy.


Assuntos
Cardiomiopatia Dilatada/enzimologia , Metaloproteinases da Matriz/metabolismo , Adulto , Biomarcadores , Colágeno/metabolismo , Colagenases/metabolismo , Ecocardiografia/métodos , Eletroforese em Gel de Poliacrilamida , Feminino , Fibrose , Cardiopatias/terapia , Transplante de Coração , Humanos , Concentração Inibidora 50 , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo , Necrose , Tetraciclina/metabolismo , Tetraciclina/farmacologia , Fatores de Tempo
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