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1.
J Community Health ; 49(3): 385-393, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38032459

RESUMO

OBJECTIVE: This study utilizes geospatial analytic techniques to examine HIV hotspots in Alabama leveraging Medicaid utilization data. METHODS: This cross-sectional study leveraged Medicaid utilization data from Alabama's 67 counties, averaging 9,861 Medicaid recipients aged > 18 years old per county. We used Alabama Medicaid administrative claims data from January 1, 2016, to December 31, 2020, to identify individuals with HIV. Using Microsoft SQL Server, we obtained the average annual count of HIV Medicaid claims in each of the 67 Alabama counties (numerator) and the number of adult Medicaid recipients in each county (denominator), and standardized with a multiplier of 100,000. We also examined several other area-level summary variables (e.g., non-high school completion, income greater than four times the federal poverty level, social associations, urbanicity/rurality) as social and structural determinants of health. County-boundary choropleth maps were created representing the geographic distribution of HIV rates per 100,000 adult Medicaid recipients in Alabama. Leveraging ESRI ArcGIS and local indicators of spatial association (LISA), results were examined using local Moran's I to identify geographic hotspots. RESULTS: Eleven counties had HIV rates higher than 100 per 100,000. Three were hotspots. Being an HIV hotspot was significantly associated with relatively low educational attainment and less severe poverty than other areas in the state. CONCLUSIONS: Findings suggesting that the HIV clusters in Alabama were categorized by significantly less severe poverty and lower educational attainment can aid ongoing efforts to strategically target resources and end the HIV epidemic in U.S.' Deep South.


Assuntos
Infecções por HIV , Determinantes Sociais da Saúde , Adulto , Estados Unidos/epidemiologia , Humanos , Adolescente , Alabama/epidemiologia , Prevalência , Estudos Transversais , Medicaid , Infecções por HIV/epidemiologia
2.
Osteoarthritis Cartilage ; 31(2): 199-212, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36354073

RESUMO

OBJECTIVE: Transcriptomic changes in joint tissues during the development of osteoarthritis (OA) are of interest for the discovery of biomarkers and mechanisms of disease. The objective of this study was to use the rat medial meniscus transection (MMT) model to discover stage and tissue-specific transcriptomic changes. DESIGN: Sham or MMT surgeries were performed in mature rats. Cartilage, menisci and synovium were scored for histopathological changes at 2, 4 and 6 weeks post-surgery and processed for RNA-sequencing. Differentially expressed genes (DEG) were used to identify pathways and mechanisms. Published transcriptomic datasets from animal models and human OA were used to confirm and extend present findings. RESULTS: The total number of DEGs was already high at 2 weeks (723 in meniscus), followed by cartilage (259) and synovium (42) and declined to varying degrees in meniscus and synovium but increased in cartilage at 6 weeks. The most upregulated genes included tenascins. The 'response to mechanical stimulus' and extracellular matrix-related pathways were enriched in both cartilage and meniscus. Pathways that were enriched in synovium at 4 weeks indicate processes related to synovial hyperplasia and fibrosis. Synovium also showed upregulation of IL-11 and several MMPs. The mechanical stimulus pathway included upregulation of the mechanoreceptors PIEZO1, PIEZO2 and TRPV4 and nerve growth factor. Analysis of data from prior RNA-sequencing studies of animal models and human OA support these findings. CONCLUSION: These results indicate several shared pathways that are affected during OA in cartilage and meniscus and support the role of mechanotransduction and other pathways in OA pathogenesis.


Assuntos
Cartilagem Articular , Osteoartrite , Humanos , Ratos , Animais , Transcriptoma , Mecanotransdução Celular , Cartilagem Articular/patologia , Osteoartrite/metabolismo , Membrana Sinovial/metabolismo , Matriz Extracelular/metabolismo , RNA/metabolismo , Modelos Animais de Doenças , Canais Iônicos/metabolismo , Canais de Cátion TRPV/metabolismo
3.
Int J Obes (Lond) ; 39(2): 371-4, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24946909

RESUMO

Many eating studies in psychology, consumer behavior and marketing journals are dismissed, because they focus on how much one serves and not how much is eaten. We develop a means of estimating the percentage of self-served food that is consumed under various conditions. An aggregate analysis was conducted of studies where participants served themselves food and where actual intake was measured. Analyses explored what percentage of food was consumed depending on population, food and situational cues and generally showed that adults consistently consume the vast majority (91.7%) of what they serve themselves. This was higher for meals (92.8%) than for snacks (76.1%) and higher when a person was not distracted (97.1%) than when he or she was distracted (88.8%). The percentage eaten did not vary between lab (90.7%) and field settings (91.9%). Because many eating behavior studies outside of nutrition measure food selection, but not intake, the aggregate estimates presented in this research can enable obesity, nutrition and public health researchers to extrapolate how much may have been eaten in such studies. Doing so will extend their relevance to better understanding eating behavior and better developing solutions to overeating.


Assuntos
Comportamento Alimentar , Preferências Alimentares/psicologia , Serviços de Alimentação/estatística & dados numéricos , Inquéritos sobre Dietas , Ingestão de Energia , Comportamento Alimentar/psicologia , Humanos , Refeições , Obesidade/epidemiologia , Tamanho da Porção
4.
Neuropathol Appl Neurobiol ; 41(1): 24-46, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25556536

RESUMO

Hereditary frontotemporal dementia associated with mutations in the microtubule-associated protein tau gene (MAPT) is a protean disorder. Three neuropathologic subtypes can be recognized, based on the presence of inclusions made of tau isoforms with three and four repeats, predominantly three repeats and mostly four repeats. This is relevant for establishing a correlation between structural magnetic resonance imaging and positron emission tomography using tracers specific for aggregated tau. Longitudinal studies will be essential to determine the evolution of anatomical alterations from the asymptomatic stage to the various phases of disease following the onset of symptoms.


Assuntos
Encéfalo/patologia , Demência Frontotemporal/genética , Demência Frontotemporal/patologia , Mutação , Proteínas tau/genética , Encéfalo/diagnóstico por imagem , Feminino , Demência Frontotemporal/diagnóstico por imagem , Humanos , Corpos de Inclusão/metabolismo , Corpos de Inclusão/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fosforilação , Tomografia por Emissão de Pósitrons , Isoformas de Proteínas/genética , Tomografia Computadorizada de Emissão , Proteínas tau/metabolismo
5.
J Dairy Sci ; 98(2): 1354-61, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25497825

RESUMO

The purpose of these experiments was to (1) assess differences in mastitis pathogen strain sensitivities to teat disinfectants (teat dips), and (2) determine the optimum time for premilking teat dips to remain in contact with teat skin to reduce pathogen loads on teat skin. Two experiments were conducted using the excised teat model. In experiment 1, the differences in mastitis pathogen strain sensitivities to 4 commercially available dips (dip A: 1% H2O2; dip B: 1% chlorine dioxide; dip C: 1% iodophor; and dip D: 0.5% iodophor) were evaluated. Four strains of 11 common mastitis pathogens (Staphylococcus aureus, Streptococcus agalactiae, Mycoplasma bovis, Streptococcus dysgalactiae, Streptococcus uberis, Escherichia coli, Staphylococcus chromogenes, Staphylococcus epidermidis, Staphylococcus hyicus, Staphylococcus xylosus, and Staphylococcus haemolyticus) were tested. In experiment 2, the percentage log reduction of mastitis pathogens (Escherichia coli, Streptococcus uberis, Streptococcus dysgalactiae, Klebsiella species, Staphylococcus chromogenes, Staphylococcus haemolyticus, Staphylococcus xylosus, and Staphylococcus epidermidis) on teat skin with 3 commercially available teat dips: dip A; dip D; and dip E: 0.25% iodophor, using dip contact times of 15, 30, and 45 s, was evaluated. Experiment 1 results indicated significant differences in strain sensitivities to dips within pathogen species: Staphylococcus aureus, Staphylococcus chromogenes, and Streptococcus uberis. Species differences were also found where Mycoplasma bovis (97.9% log reduction) was the most sensitive to tested teat dips and Staphylococcus haemolyticus (71.4% log reduction) the most resistant. Experiment 2 results indicated that contact times of 30 and 45 s were equally effective in reducing recovered bacteria for dips D and E and were also significantly more effective than a 15-s contact time. No differences were seen in recovered bacteria between tested contact times after treatment with dip A. It can be concluded that different mastitis pathogen species and strains within species may possess different sensitivities to teat dips, which may have implications in selection of teat dips on dairies. Furthermore, a 30-s premilking dip contact time for iodophors and 15 s for H2O2 dips may be optimal in reducing pathogen load in the shortest amount of time. A reduction in premilking teat dip contact time may improve milking parlor efficiency.


Assuntos
Anti-Infecciosos Locais/administração & dosagem , Carga Bacteriana/efeitos dos fármacos , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/microbiologia , Mastite Bovina/prevenção & controle , Animais , Bovinos , Compostos Clorados/administração & dosagem , Escherichia coli/efeitos dos fármacos , Feminino , Peróxido de Hidrogênio/administração & dosagem , Glândulas Mamárias Animais/efeitos dos fármacos , Óxidos/administração & dosagem , Salicilatos , Pele/microbiologia , Especificidade da Espécie , Infecções Estafilocócicas/veterinária , Staphylococcus/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Infecções Estreptocócicas/veterinária , Streptococcus/efeitos dos fármacos , Streptococcus agalactiae , Fatores de Tempo
6.
J Prev Alzheimers Dis ; 11(4): 831-837, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39044491

RESUMO

BACKGROUND: Individuals from diverse racial and ethnic groups are severely underrepresented in Alzheimer's disease trials in part due to disproportionate biomarker ineligibility. Evidence from recent studies support plasma phosphorylated tau 217 (P-tau217) as an early marker for brain Aß pathology and a reliable marker in predicting elevated brain amyloid PET in cognitively unimpaired adults. OBJECTIVES: To examine whether the relationship between P-tau217 and 18-F florbetapir PET standard uptake value ratios (SUVR) is influenced by race and ethnicity in the Anti-Amyloid treatment in Asymptomatic Alzheimer's disease (A4) preclinical AD studies. DESIGN: We conducted a retrospective analysis of A4 clinical trial and the LEARN natural history companion study data to evaluate the relationship between baseline P-tau217 and PET SUVR concentration levels by race and ethnicity. SETTING: The analysis was conducted on samples from participants enrolled across 65 study sites in the United States and Canada. PARTICIPANTS: Cognitively unimpaired adults aged 65-85 enrolled at North American sites in the A4 preclinical AD trial, pre-dose, (N=1018), and the LEARN (N=480) study. Participants were grouped into 2 categories, racial and ethnic underrepresented group (RE-URG) and non-RE-URG (nRE-URG) based on self-identification. MEASUREMENTS: A mixed-effects regression model was fit to determine differences in the relationship between P-tau217 and PET SUVR by race and ethnicity, adjusting for age, and APOE ε4 carrier status. RESULTS: Results from the linear mixed-effects model support that there was no statistically significant effect of race and ethnicity on the relationship between P-tau217 and PET SUVR. CONCLUSION: These findings suggest that the relationship between plasma P-tau217 and PET SUVR is the same across race and ethnicity. Future analyses should corroborate these findings in a larger sample and examine whether plasma P-tau217 reflects the differential amyloid prevalence previously reported for other biomarkers of amyloid.


Assuntos
Doença de Alzheimer , Tomografia por Emissão de Pósitrons , Proteínas tau , Humanos , Idoso , Feminino , Masculino , Proteínas tau/metabolismo , Proteínas tau/sangue , Doença de Alzheimer/sangue , Doença de Alzheimer/metabolismo , Doença de Alzheimer/diagnóstico por imagem , Idoso de 80 Anos ou mais , Estudos Retrospectivos , Compostos de Anilina , Etnicidade , Biomarcadores/sangue , Biomarcadores/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Grupos Raciais , Estados Unidos , Canadá , Etilenoglicóis , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/sangue , Fosforilação
7.
J Prev Alzheimers Dis ; 11(4): 823-830, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39044490

RESUMO

BACKGROUND: Blood-based AD biomarkers such as plasma P-tau217 are increasingly used in clinical trials as a screening tool. OBJECTIVES: To assess the utility of an electrochemiluminescence (ECL) immunoassay in predicting brain amyloid PET status in cognitively unimpaired individuals. SETTING: Plasma samples collected at baseline, week 12, and week 240 or endpoint originated from the Anti-Amyloid Treatment in Asymptomatic Alzheimer's Disease (A4) trial and the companion Longitudinal Evaluation of Amyloid Risk and Neurodegeneration (LEARN) study. PARTICIPANTS: Both A4 and LEARN enrolled eligible cognitively unimpaired persons 65 to 85 years. Individuals with elevated brain amyloid PET levels were eligible for the A4 Study, while those without elevated brain amyloid PET levels were eligible for the LEARN Study. INTERVENTION: Participants in the A4 Study received intravenous solanezumab (up to 1600 mg) or placebo every 4 weeks. The LEARN Study is an observational study without intervention. MEASUREMENTS: Plasma P-tau217 concentration levels from A4 Study participants were measured using an ECL immunoassay. Receiver Operating Characteristic (ROC) curve analysis was performed for each biomarker against amyloid positivity, defined by ≥22 CL and ≥ 33 CL. RESULTS: Receiver operating characteristic curve (ROC) analysis indicates high diagnostic value of P-tau217 in individuals with amyloid PET ≥ 20 (Area under the ROC (AUROC): 0.87) and ≥ 33 CL (AUROC: 0.89). Repeated testing with the placebo group taken 12 weeks apart (range: 68 to 143 days) and the LEARN participants taken between 1.4 and 1.75 years resulted in a strong positive correlation (Corr. 0.91 (0.90 to 0.92)). CONCLUSION: An ECL immunoassay testing plasma P-tau217 accurately predicts amyloid PET positivity in cognitively unimpaired individuals. Our future analyses aim to determine if use of this assay may reduce the screening burden of preclinical individuals into anti-amyloid clinical trials.


Assuntos
Doença de Alzheimer , Biomarcadores , Tomografia por Emissão de Pósitrons , Proteínas tau , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Idoso , Proteínas tau/sangue , Masculino , Feminino , Biomarcadores/sangue , Idoso de 80 Anos ou mais , Estudos Longitudinais , Anticorpos Monoclonais Humanizados/uso terapêutico , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Peptídeos beta-Amiloides/sangue , Peptídeos beta-Amiloides/metabolismo
8.
J Prev Alzheimers Dis ; 11(4): 802-813, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39044488

RESUMO

BACKGROUND: Converging evidence suggests that markers of Alzheimer's disease (AD) pathology in cognitively unimpaired older individuals are associated with high risk of cognitive decline and progression to functional impairment. The Anti-Amyloid Treatment in Asymptomatic Alzheimer's disease (A4) and Longitudinal Evaluation of Amyloid and Neurodegeneration Risk (LEARN) Studies enrolled a large cohort of cognitively normal older individuals across a range of baseline amyloid PET levels. Recent advances in AD blood-based biomarkers further enable the comparison of baseline markers in the prediction of longitudinal clinical outcomes. OBJECTIVES: We sought to evaluate whether biomarker indicators of higher levels of AD pathology at baseline predicted greater cognitive and functional decline, and to compare the relative predictive power of amyloid PET imaging, tau PET imaging, and a plasma P-tau217 assay. DESIGN: All participants underwent baseline amyloid PET scan, plasma P-tau217; longitudinal cognitive testing with the Primary Alzheimer Cognitive Composite (PACC) every 6 months; and annual functional assessments with the clinical dementia rating (CDR), cognitive functional index (CFI), and activities of daily living (ADL) scales. Baseline tau PET scans were obtained in a subset of participants. Participants with elevated amyloid (Aß+) on screening PET who met inclusion/exclusion criteria were randomized to receive placebo or solanezumab in a double-blind phase of the A4 Study over 240+ weeks. Participants who did not have elevated amyloid (Aß-) but were otherwise eligible for the A4 Study were referred to the companion observational LEARN Study with the same outcome assessments over 240+ weeks. SETTING: The A4 and LEARN Studies were conducted at 67 clinical trial sites in the United States, Canada, Japan and Australia. PARTICIPANTS: Older participants (ages 65-85) who were cognitively unimpaired at baseline (CDR-GS=0, MMSE 25-30 with educational adjustment, and Logical Memory scores within the normal range LMIIa 6-18) were eligible to continue in screening. Aß+ participants were randomized to either placebo (n=583) or solanezumab (n=564) in the A4 Study. A subset of Aß+ underwent tau PET imaging in A4 (n=350). Aß- were enrolled into the LEARN Study (n=553). MEASUREMENTS: Baseline 18-F Florbetapir amyloid PET, 18-F Flortaucipir tau PET in a subset and plasma P-tau217 with an electrochemiluminescence (ECL) immunoassay were evaluated as predictors of cognitive (PACC), and functional (CDR, CFI and ADL) change. Models were evaluated to explore the impact of baseline tertiles of amyloid PET and tertiles of plasma P-tau217 on cognitive and functional outcomes in the A4 Study compared to LEARN. Multivariable models were used to evaluate the unique and common variance explained in longitudinal outcomes based on baseline predictors, including effects for age, gender, education, race/ethnic group, APOEε4 carrier status, baseline PACC performance and treatment assignment in A4 participants (solanezumab vs placebo). RESULTS: Higher baseline amyloid PET CL and P-tau217 levels were associated with faster rates of PACC decline, and increased likelihood of progression to functional impairment (CDR 0.5 or higher on two consecutive measurements), both across LEARN Aß- and A4 Aß+ (solanezumab and placebo arms). In analyses considering all baseline predictor variables, P-tau217 was the strongest predictor of PACC decline. Among participants in the highest tertiles of amyloid PET or P-tau217, >50% progressed to CDR 0.5 or greater. In the tau PET substudy, neocortical tau was the strongest predictor of PACC decline, but plasma P-tau217 contributed additional independent predictive variance in commonality variance models. CONCLUSIONS: In a large cohort of cognitively unimpaired individuals enrolled in a Phase 3 clinical trial and companion observational study, these findings confirm that higher baseline levels of amyloid and tau markers are associated with increased rates of cognitive decline and progression to functional impairment. Interestingly, plasma P-tau217 was the best predictor of decline in the overall sample, superior to baseline amyloid PET. Neocortical tau was the strongest predictor of cognitive decline in the subgroup with tau PET, suggesting that tau deposition is most closely linked to clinical decline. These findings indicate that biomarkers of AD pathology are useful to predict decline in an older asymptomatic population and may prove valuable in the selection of individuals for disease-modifying treatments.


Assuntos
Biomarcadores , Disfunção Cognitiva , Tomografia por Emissão de Pósitrons , Proteínas tau , Humanos , Feminino , Idoso , Masculino , Proteínas tau/sangue , Estudos Longitudinais , Biomarcadores/sangue , Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Atividades Cotidianas , Anticorpos Monoclonais Humanizados/uso terapêutico , Peptídeos beta-Amiloides/sangue , Peptídeos beta-Amiloides/metabolismo , Idoso de 80 Anos ou mais , Progressão da Doença , Compostos de Anilina
9.
Perfusion ; 28(6): 541-5, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23804956

RESUMO

A low haematocrit during cardiopulmonary bypass (CPB) is associated with adverse outcomes and often results in homologous blood transfusions. Oxygenators with improved venous reservoir designs aid in reducing the priming volume. Recently, we changed our small adult oxygenator model from the D905 EOS oxygenator (Dideco, Mirandola, Italy) to the Capiox FX1540 (Terumo Corporation, Tokyo, Japan). We conducted a retrospective study of 42 patents to evaluate the impact of the Capiox FX 1540 on blood transfusion requirements in small patients (body surface area (BSA) up to 1.8 m(2)). The D905 EOS group had a lower minimum intraoperative haematocrit than the FX1540 group (20 ± 3 v 22 ± 4, p = 0.029) with 73% of the patients receiving intraoperative blood transfusions compared with 30% in the FX 1540 group (p = 0.012). Patients in the D905 EOS group received one blood transfusion more during CPB than the FX 1540 patients (p = 0.002). The haematocrits at the end of CPB and in the early postoperative period were identical in both groups. The postoperative ventilation time, length of stay in the intensive care unit and postoperative chest drain bleeding were similar in both groups. In conclusion, the Capiox FX1540 was effective in reducing intraoperative packed red cell transfusions.


Assuntos
Transfusão de Sangue/instrumentação , Transfusão de Sangue/métodos , Ponte Cardiopulmonar/métodos , Oxigenadores , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos
10.
Haemophilia ; 18(5): 699-707, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22507546

RESUMO

This study describes health-related quality of life (HRQoL) of persons with haemophilia A in the United States (US) and determines associations between self-reported joint pain, motion limitation and clinically evaluated joint range of motion (ROM), and between HRQoL and ROM. As part of a 2-year cohort study, we collected baseline HRQoL using the SF-12 (adults) and PedsQL (children), along with self-ratings of joint pain and motion limitation, in persons with factor VIII deficiency recruited from six Haemophilia Treatment Centres (HTCs) in geographically diverse regions of the US. Clinically measured joint ROM measurements were collected from medical charts of a subset of participants. Adults (N = 156, mean age: 33.5 ± 12.6 years) had mean physical and mental component scores of 43.4 ± 10.7 and 50.9 ± 10.1, respectively. Children (N = 164, mean age: 9.7 ± 4.5 years) had mean total PedsQL, physical functioning, and psychosocial health scores of 85.9 ± 13.8, 89.5 ± 15.2, and 84.1 ± 15.3, respectively. Persons with more severe haemophilia and higher self-reported joint pain and motion limitation had poorer scores, particularly in the physical aspects of HRQoL. In adults, significant correlations (P < 0.01) were found between ROM measures and both self-reported measures. Except among those with severe disease, children and adults with haemophilia have HRQoL scores comparable with those of the healthy US population. The physical aspects of HRQoL in both adults and children with haemophilia A in the US decrease with increasing severity of illness. However, scores for mental aspects of HRQoL do not differ between severity groups. These findings are comparable with those from studies in European and Canadian haemophilia populations.


Assuntos
Hemofilia A/fisiopatologia , Adolescente , Adulto , Artralgia/fisiopatologia , Criança , Pré-Escolar , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Amplitude de Movimento Articular , Estados Unidos , Adulto Jovem
11.
J Prev Alzheimers Dis ; 9(4): 617-624, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36281665

RESUMO

BACKGROUND: Screening data from the Anti-Amyloid Treatment in Asymptomatic Alzheimer's Disease (A4) and Longitudinal Evaluation of Amyloid Risk and Neurodegeneration (LEARN) studies provide a unique opportunity to compare magnetic resonance imaging (MRI) findings such as amyloid-related imaging abnormalities (ARIA) in cognitively unimpaired elderly with and without elevated cerebral amyloid. OBJECTIVES: To compare screening MRI findings, such as ARIA, in the cognitively unimpaired potential participants of a clinical trial with and without elevated cerebral amyloid. DESIGN: Cross-sectional analysis of structural MRI findings in screening data from the A4 and LEARN studies. SETTING: The A4 Study is a multi-center international clinical trial. The LEARN Study is a multi center observational study in the United States. PARTICIPANTS: Clinically normal older adults (65-85 years) with elevated cerebral amyloid (Aß+; n = 1250, A4) and without elevated cerebral amyloid (Aß-; n = 538, LEARN). MEASUREMENTS: Participants underwent florbetapir positron emission tomography for Aß+/- classification. A centrally read 3T MRI to assess for study eligibility was conducted on study qualified MRI scanners. RESULTS: No ARIA-effusions (ARIA-E) was detected on screening MRI in the Aß+ or Aß- cohorts. At least one ARIA-H (microhemorrhages [MCH] or superficial siderosis [SS]) was present in 18% of the Aß+ cohort compared with 8% in Aß- (P < 0.001). In the Aß+ cohort, approximately 2% of screening MRIs demonstrated MCH ≥4 compared with 0% in Aß-. The presence of two apolipoprotein E ε4 (APOEε4) alleles (vs no ε4 alleles) in the Aß+ cohort increased the odds for presence of MCH (odds ratio [OR] = 2.03; 95% CI, 1.23 to 3.27, P = 0.004). Cortical infarctions (4% vs 0%) and subcortical infarctions (10% vs 1%) were observed at statistically significantly higher prevalence in the Aß+ cohort compared with Aß- (P < 0.001). Females showed reduced odds of MCH in the Aß+ cohort by a factor of 0.63 (95% CI, 0.47 to 0.84, P = 0.002). CONCLUSIONS: ARIA-E is rare in cognitively unimpaired Aß+ and Aß- populations prior to anti-amyloid drug intervention. ARIA-H in Aß+ was greater than in Aß- populations.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Idoso , Feminino , Humanos , Doença de Alzheimer/tratamento farmacológico , Amiloide , Apolipoproteína E4 , Estudos Transversais , Imageamento por Ressonância Magnética , Idoso de 80 Anos ou mais , Masculino
12.
J Prev Alzheimers Dis ; 9(4): 801-808, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36281685

RESUMO

BACKGROUND: Performance of cognitively complex "instrumental activities of daily living" (IADL) has previously been related to amyloid deposition in preclinical Alzheimer's disease. OBJECTIVES: We aimed to investigate the relationship between IADL performance and cerebral tau accumulation in cognitively normal older adults. DESIGN: Cross-sectional. SETTING: Data was collected in the Anti-Amyloid Treatment in Asymptomatic Alzheimer's (A4) and Longitudinal Evaluation of Amyloid Risk and Neurodegeneration (LEARN) studies. PARTICIPANTS: Participants (n = 447, age 71.9±4.9 years, 57.5% female) who underwent tau positron emission tomography were selected from the A4 and LEARN studies. MEASUREMENTS: IADL performance was measured using the self- and study partner-reported versions of the Alzheimer's Disease Cooperative Study Activities of Daily Living - Prevention Instrument (ADCS ADL-PI). We also investigated discordance between participants and their study partners. Cross-sectional associations between entorhinal and inferior temporal tau (independent variables) and ADCS ADL-PI total scores, item-level scores and discordance (dependent variables) were investigated in linear and logistic regressions. Analyses were adjusted for age, sex and education and a tau by amyloid interaction was also included. RESULTS: Participants and their study partners reported high levels of IADL performance. Entorhinal and inferior temporal tau were related to study partner but not to self-reported total ADCS ADL-PI scores. The association was not retained after adjustment for global cerebral amyloid burden. At the item level, greater entorhinal tau was associated with study partner-reported difficulties remembering important dates (odds ratio (OR) = 1.24, 95% confidence interval (95%CI) = [1.06, 1.45], p = 0.008) and difficulties remembering the details of TV programs and movies (OR = 1.32, 95%CI = [1.08, 1.61], p = 0.007). Greater inferior temporal tau was associated with self-reported difficulties managing to find personal belongings (OR = 1.23, 95%CI = [1.04, 1.46], p = 0.018) and study partner-reported difficulties remembering the details of TV programs and movies (OR = 1.39, 95%CI = [1.11, 1.75], p = 0.005). Discordance between participant and study partner-report was more likely with greater entorhinal (OR = 1.18, 95%CI = [1.05, 1.33], p = 0.005) and inferior temporal tau burden (OR = 1.29, 95%CI = [1.10, 1.51], p = 0.002). DISCUSSION: We found a cross-sectional relationship between study partner-reported everyday functioning and tau in cognitively normal older adults. Participants were more likely to self-report difficulties differently from their study partners when tau burden was higher. This may hint at an altered early-disease awareness of functional changes and underscores the importance of self-report of IADL functioning in addition to collateral report by a study partner.


Assuntos
Doença de Alzheimer , Humanos , Feminino , Idoso , Masculino , Proteínas tau , Atividades Cotidianas , Tomografia por Emissão de Pósitrons , Amiloide
13.
Curr Opin Cell Biol ; 4(1): 80-5, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1558756

RESUMO

During the past year, studies on the centrioles and basal bodies of animal and algal cells, and the spindle pole bodies of yeast and other fungi, have added significantly to our knowledge of how these cell organelles form and how they function in initiating microtubule assembly throughout the cell cycle. Most of these studies have used antibodies to identify proteins within and around these organelles and, in some cases, to disrupt their ability to nucleate microtubules. Genetic methods have been used to identify specific proteins, including a new member of the tubulin superfamily, involved in the function and replication of spindle pole bodies and centrioles.


Assuntos
Centríolos/ultraestrutura , Replicação do DNA , Organelas/ultraestrutura , Animais , Microtúbulos/ultraestrutura , Fuso Acromático/ultraestrutura
14.
Psychol Med ; 41(4): 861-71, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20522277

RESUMO

BACKGROUND: Twin and sibling studies have identified specific cognitive phenotypes that may mediate the association between genes and the clinical symptoms of attention deficit hyperactivity disorder (ADHD). ADHD is also associated with lower IQ scores. We aimed to investigate whether the familial association between measures of cognitive performance and the clinical diagnosis of ADHD is mediated through shared familial influences with IQ. METHOD: Multivariate familial models were run on data from 1265 individuals aged 6-18 years, comprising 920 participants from ADHD sibling pairs and 345 control participants. Cognitive assessments included a four-choice reaction time (RT) task, a go/no-go task, a choice-delay task and an IQ assessment. The analyses focused on the cognitive variables of mean RT (MRT), RT variability (RTV), commission errors (CE), omission errors (OE) and choice impulsivity (CI). RESULTS: Significant familial association (rF) was confirmed between cognitive performance and both ADHD (rF=0.41-0.71) and IQ (rF=-0.25 to -0.49). The association between ADHD and cognitive performance was largely independent (80-87%) of any contribution from etiological factors shared with IQ. The exception was for CI, where 49% of the overlap could be accounted for by the familial variance underlying IQ. CONCLUSIONS: The aetiological factors underlying lower IQ in ADHD seem to be distinct from those between ADHD and RT/error measures. This suggests that lower IQ does not account for the key cognitive impairments observed in ADHD. The results have implications for molecular genetic studies designed to identify genes involved in ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtornos Cognitivos/genética , Transtornos Cognitivos/psicologia , Inteligência/genética , Testes Neuropsicológicos/estatística & dados numéricos , Fenótipo , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Criança , Comportamento de Escolha , Transtornos Cognitivos/diagnóstico , Europa (Continente) , Feminino , Humanos , Inibição Psicológica , Controle Interno-Externo , Masculino , Análise Multivariada , Determinação da Personalidade/estatística & dados numéricos , Psicometria , Tempo de Reação/genética , Recompensa
15.
Neuropsychopharmacology ; 46(2): 432-441, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33007776

RESUMO

Atypical attention orienting has been found to be impaired in many neuropsychological disorders, but the underlying neural mechanism remains unclear. Attention can be oriented exogenously (i.e., driven by salient stimuli) or endogenously (i.e., driven by one's goals or intentions). Genetic mouse models are useful tools to investigate the neurobiology of cognition, but a well-established assessment of attention orienting in mice is missing. This study aimed to adapt the Posner task, a widely used attention orienting task in humans, for use in mice using touchscreen technology and to test the effects of two attention-modulating drugs, methylphenidate (MPH) and atomoxetine (ATX), on the performance of mice during this task. In accordance with human performance, mice responded more quickly and more accurately to validly cued targets compared to invalidly cued targets, thus supporting mice as a valid animal model to study the neural mechanisms of attention orienting. This is the first evidence that mice can be trained to voluntarily maintain their nose-poke on a touchscreen and to complete attention orienting tasks using exogenous peripheral cues and endogenous symbolic cues. The results also showed no significant effects of MPH and ATX on attention orienting, although MPH improved overall response times in mice during the exogenous orienting task. In summary, the current study provides a critical translational task for assessing attention orienting in mice and to investigate the effects of attention-modulating drugs on attention orienting.


Assuntos
Atenção , Sinais (Psicologia) , Animais , Camundongos , Tempo de Reação
16.
J Prev Alzheimers Dis ; 8(3): 257-262, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34101781

RESUMO

BACKGROUND: Greater subjective cognitive changes on the Cognitive Function Index (CFI) was previously found to be associated with elevated amyloid (Aß) status in participants screening for the A4 Study, reported by study partners and the participants themselves. While the total score on the CFI related to amyloid for both sources respectively, potential differences in the specific types of cognitive changes reported by either participants or their study partners was not investigated. OBJECTIVES: To determine the specific types of subjective cognitive changes endorsed by participants and their study partners that are associated with amyloid status in individuals screening for an AD prevention trial. DESIGN, SETTING, PARTICIPANTS: Four thousand four hundred and eighty-six cognitively unimpaired (CDR=0; MMSE 25-30) participants (ages 65-85) screening for the A4 Study completed florbetapir (Aß) Positron Emission Tomography (PET) imaging. Participants were classified as elevated amyloid (Aß+; n=1323) or non-elevated amyloid (Aß-; n=3163). MEASUREMENTS: Prior to amyloid PET imaging, subjective report of changes in cognitive functioning were measured using the CFI (15 item questionnaire; Yes/Maybe/No response options) and administered separately to both participants and their study partners (i.e., a family member or friend in regular contact with the participant). The impact of demographic factors on CFI report was investigated. For each item of the CFI, the relationship between Aß and CFI response was investigated using an ordinal mixed effects model for participant and study partner report. RESULTS: Independent of Aß status, participants were more likely to report 'Yes' or 'Maybe' compared to the study partners for nearly all CFI items. Older age (r= 0.06, p<0.001) and lower education (r=-0.08, p<0.001) of the participant were associated with higher CFI. Highest coincident odds ratios related to Aß+ for both respondents included items assessing whether 'a substantial decline in memory' had occurred in the last year (ORsp= 1.35 [95% CI 1.11, 1.63]; ORp= 1.55 [95% CI 1.34, 1.79]) and whether the participant had 'seen a doctor about memory' (ORsp= 1.56 [95% CI 1.25, 1.95]; ORp =1.71 [95% CI 1.37, 2.12]). For two items, associations were significant for only study partner report; whether the participant 'Repeats questions' (ORsp = 1.30 [95% CI 1.07, 1.57]) and has 'trouble following the news' (ORsp= 1.46[95% CI 1.12, 1.91]). One question was significant only for participant report; 'trouble driving' (ORp= 1.25 [95% CI 1.04, 1.49]). CONCLUSIONS: Elevated Aß is associated with greater reporting of subjective cognitive changes as measured by the CFI in this cognitively unimpaired population. While participants were more likely than study partners to endorse change on most CFI items, unique CFI items were associated with elevated Aß for participants and their study partners, supporting the value of both sources of information in clinical trials.


Assuntos
Doença de Alzheimer/prevenção & controle , Amiloide/metabolismo , Cognição/fisiologia , Voluntários Saudáveis/estatística & dados numéricos , Testes Neuropsicológicos/estatística & dados numéricos , Autorrelato , Inquéritos e Questionários , Idoso , Idoso de 80 Anos ou mais , Compostos de Anilina , Etilenoglicóis , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Cônjuges/psicologia , Cônjuges/estatística & dados numéricos
18.
J Fish Dis ; 33(7): 559-70, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20367740

RESUMO

In this study, susceptibility and potential carrier status of burbot, Lota lota, were assessed for five important fish pathogens. Burbot demonstrated susceptibility and elevated mortality following challenge with infectious haematopoietic necrosis virus (IHNV) by immersion and to Aeromonas salmonicida by intraperitoneal (i.p.) injection. IHNV persisted in fish for at least 28 days, whereas A. salmonicida was not re-isolated beyond 17 days post-challenge. In contrast, burbot appeared refractory to Flavobacterium psychrophilum following intramuscular (i.m.) injection and to infectious pancreatic necrosis virus (IPNV) by immersion. However, i.p injection of IPNV resulted in re-isolation of virus from fish for the duration of the 28 day challenge. Renibacterium salmoninarum appeared to induce an asymptomatic carrier state in burbot following i.p. injection, but overt manifestation of disease was not apparent. Viable bacteria persisted in fish for at least 41 days, and bacterial DNA isolated by diagnostic polymerase chain reaction was detected from burbot kidney tissue 90 days after initial exposure. This study is the first to investigate susceptibility of burbot to selected fish pathogens, and this information will aid in efforts to culture and manage this species.


Assuntos
Infecções Bacterianas/veterinária , Fenômenos Fisiológicos Bacterianos , Portador Sadio/veterinária , Suscetibilidade a Doenças/veterinária , Doenças dos Peixes/imunologia , Gadiformes/imunologia , Infecções por Vírus de RNA/veterinária , Aeromonas salmonicida/fisiologia , Animais , Infecções Bacterianas/microbiologia , Infecções Bacterianas/mortalidade , Doenças dos Peixes/microbiologia , Doenças dos Peixes/virologia , Flavobacterium/fisiologia , Gadiformes/microbiologia , Gadiformes/virologia , Vírus da Necrose Hematopoética Infecciosa/fisiologia , Vírus da Necrose Pancreática Infecciosa/fisiologia , Micrococcaceae/fisiologia , Infecções por Vírus de RNA/mortalidade , Infecções por Vírus de RNA/virologia
19.
J Small Anim Pract ; 61(8): 512-515, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-30338846

RESUMO

Peripheral nerve sheath tumours arising in the plexus or peripheral nerves can be treated by limb amputation. There are few reports of these tumours affecting peripheral nerves in the distal regions of the limbs. Here we describe a case of neurofibroma affecting the palmar branch of the ulnar nerve in an Irish setter. Surgical treatment in the region of the carpus by ulnar neurectomy resulted in resolution of chronic thoracic limb lameness. At 11 months following the surgery, clinical examination and MRI did not detect any evidence of recurrence. Neurectomy may be a feasible option for management of selected cases of distally located peripheral nerve sheath tumours.


Assuntos
Doenças do Cão/cirurgia , Neurofibroma/veterinária , Animais , Denervação/veterinária , Cães , Ligamentos , Recidiva Local de Neoplasia/veterinária , Nervo Ulnar
20.
Osteoarthritis Cartilage ; 17(8): 1056-64, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19328881

RESUMO

OBJECTIVE: The transglutaminase (TG) isoenzyme TG2, which catalyzes protein cross-linking via transamidation, influences healing phenotype in multiple forms of tissue injury. Moreover, TG2 knockout suppresses cartilage destruction but promotes osteophyte formation in instability-induced mouse knee osteoarthritis (OA). TG2 is marker of growth plate chondrocyte hypertrophy. Moreover, TG2 secreted by chondrocytes acts in part by promoting chondrocyte maturation to hypertrophy, a differentiation state linked with MMP-13 expression and disease progression in OA. Moreover, glucosamine, which is currently under investigation as an OA therapy, binds and inhibits TG2. Here, we examined TG2 as a potential marker of cartilage hypertrophy in the spontaneous guinea pig model of OA. METHODS: Synovial fluid ELISA and cartilage Immunohistochemistry and quantitative Reverse transcription-polymerase chain reaction (RT-PCR), were used to examine TG2 expression and TG transamidation-catalyzed isopeptide bonds. RESULTS: TG isopeptide bonds and TG2 were most abundant in articular cartilage in early knee OA. TG2 expression was robust at sites of early but not established osteophytes. Synovial fluid TG2 correlated with knee OA total histological score (r=0.47, P=0.01), as did medial tibial plateau cartilage TG2 mRNA (r=1.0, P=0.003). At 12 months of age, medial tibial plateau cartilage TG2 mRNA expression rose markedly in association with elevated type X collagen, as well as ADAMTS-5, and MMP-13 expression, changes not shared in age-matched Strain 13 guinea pigs that are less susceptible to knee OA. CONCLUSION: Hartley guinea pig knee TG2 expression associates with enhanced articular chondrocyte hypertrophy and is a biomarker of OA severity.


Assuntos
Artrite Experimental/patologia , Cartilagem Articular/patologia , Proteínas de Ligação ao GTP/metabolismo , Osteoartrite do Joelho/patologia , Transglutaminases/metabolismo , Animais , Artrite Experimental/genética , Biomarcadores/metabolismo , Condrócitos/metabolismo , Expressão Gênica , Cobaias , Imuno-Histoquímica , Osteoartrite do Joelho/genética , Proteína 2 Glutamina gama-Glutamiltransferase , Índice de Gravidade de Doença
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