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1.
Am J Prev Cardiol ; 18: 100664, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38665251

RESUMO

Background: Statins are a cost-effective therapy for prevention of atherosclerotic cardiovascular disease (ASCVD). Guidelines on statins for primary prevention are unclear for older adults (>75 years). Objective: Investigate statin utility in older adults without ASCVD events, by risk stratifying in a large healthcare network. Methods: We included 8,114 older adults, without CAD, PVD or ischemic stroke. Statin utilization based on ACC/AHA 10-year ASCVD risk calculation, was evaluated in intermediate (7.5%-19.9%) and high-risk patients (≥ 20%); and categorized using low and 'moderate or high' intensity statins with a follow up period of ∼7 years. Cox regression models were used to calculate hazard ratios for incident ASCVD and mortality across risk categories stratified by statin utilization. Data was adjusted for competing risk using Elixhauser Comorbidity Index. Results: Compared with those on moderate or high intensity statins, high-risk older patients not on any statin had a significantly increased risk of MI [HR 1.51 (1.17-1.95); p<0.01], stroke [HR 1.47 (1.14-1.90); p<0.01] and all-cause mortality [HR 1.37 (1.19-1.58); p<0.001] in models adjusted for Elixhauser Comorbidity Index. When comparing the no statin group versus the moderate or high intensity statin group in the intermediate risk cohort, although a trend for increased risk was seen, it did not meet statistical significance thresholds for MI, stroke or all-cause mortality. Conclusion: Lack of statin use was associated with increased cardiovascular events and mortality in high-risk older adults. Given the benefits appreciated, statin use may need to be strongly considered for primary ASCVD prevention among high-risk older adults. Future studies will assess the risk-benefit ratio of statin intervention in older adults.

3.
Orthopedics ; 44(3): e407-e413, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34039205

RESUMO

Same-day bilateral total knee arthroplasties (SBTKAs) are associated with shorter rehabilitation and lower cost. However, controversy surrounding the safety of SBTKAs exists. Recent studies are lacking to determine whether patient selection has brought SBTKA in line with unilateral total knee arthroplasty (UTKA). Therefore, the authors evaluated and compared patient characteristics, hospital characteristics, and inpatient course between UTKA and SBTKA from 2009 to 2016. The National Inpatient Sample was queried from 2009 to 2016 for UTKA and SBTKA patients. Of the 5,329,466 patients identified, 5,084,328 (95.4%) patients received UTKAs and 245,138 (4.6%) patients underwent SBTKAs. Incidence, rate, patient and hospital characteristics, health status, length of stay (LOS), discharge disposition, hospital charges, hospital costs, and complications were analyzed and statistically compared. The incidence (-1.4%) and rate (15.8%) of SBTKAs decreased (both P<.001). The SBTKA cohort had more patients who were younger, male, White, obese, healthier, and using private insurance (P<.001 for all). The SBTKA cohort had longer LOS, a higher proportion of discharges to skilled nursing facilities, higher cost and charges, and more complications, including deep venous thromboses/pulmonary emboli (DVT/PE) and transfusions (P<.001 for all). Conversely, SBTKA was associated with fewer myocardial infarctions (P<.001). Although improved from previous literature, SBTKA is still associated with longer LOS, higher cost and charges, and more complications, including DVT/PE and transfusions, although with a lower rate of myocardial infarction. However, studies are needed to determine whether the risk of 1 SBTKA outweighs the cumulative risk of staged UTKAs. [Orthopedics. 2021;44(3):e407-e413.].


Assuntos
Artroplastia do Joelho/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Idoso , Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/economia , Transfusão de Sangue/estatística & dados numéricos , Bases de Dados Factuais , Honorários e Preços/estatística & dados numéricos , Feminino , Custos de Cuidados de Saúde/estatística & dados numéricos , Preços Hospitalares , Humanos , Incidência , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Alta do Paciente/estatística & dados numéricos , Seleção de Pacientes , Complicações Pós-Operatórias/etiologia , Embolia Pulmonar/epidemiologia , Embolia Pulmonar/etiologia , Estudos Retrospectivos , Estados Unidos/epidemiologia , Trombose Venosa/epidemiologia , Trombose Venosa/etiologia
4.
J Am Pharm Assoc (2003) ; 61(3): e19-e27, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33386240

RESUMO

OBJECTIVE: This review describes the current educational interventions that have been created for pharmacists after the implementation of a standing order for naloxone. METHODS: Search strategies were constructed for 3 databases (PubMed, SCOPUS, and CINAHL), which were queried between February 1, 2019, and March 5, 2019. Two reviewers independently screened 224 titles and abstracts from these databases. The descriptive criteria of each study, such as rationale, design, study location, population, and method of intervention, were included. RESULTS: Eight articles met the inclusion criteria; 4 were delivered in person, 2 were online programs, and 2 used combined in-person and online methodologies. Of the 8 studies, 4 were delivered to practicing pharmacists, and 4 were designed for student pharmacists. CONCLUSION: Pharmacists seem to engage in more overdose prevention behaviors after participating in the novel educational program as compared with taking the state-mandated training alone. Both student pharmacists and practicing pharmacists had promising postintervention results, with post-test scores indicating a statistically significant increase in knowledge or improvement in naloxone-relevant skills. The results of this review indicate the need to critically analyze the implementation of standing order laws for naloxone, specifically how pharmacists are being trained. The next steps include publication of existing best practices for educational interventions for pharmacists that may not currently be in the literature.


Assuntos
Overdose de Drogas , Prescrições Permanentes , Overdose de Drogas/tratamento farmacológico , Overdose de Drogas/prevenção & controle , Humanos , Naloxona/uso terapêutico , Antagonistas de Entorpecentes/uso terapêutico , Farmacêuticos , Estudantes
5.
Orthopedics ; 44(2): e266-e273, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33373460

RESUMO

Maryland implemented the all-payer, rater-setting Global Budget Revenue (GBR) payment model in 2014 to reduce cost and improve quality. This study assessed the effect of GBR on total knee arthroplasty (TKA) outcomes by sex. Specifically, the authors assessed (1) demographics and (2) outcomes of males and females undergoing TKA before and after GBR implementation. The Maryland State Inpatient Database was queried from 2011 to 2016. There were 71,066 TKAs (male, n=25,413; female, n=45,634). For continuous and categorical variables, t testing and chi-square analyses were used, respectively. Difference-in-difference analyses using multiple regression compared changes in sex from the pre-GBR period (2011-2013) with the post-GBR period (2014-2016). The female proportion decreased (-1.9%; P=.040). Proportionally more TKA patients were Hispanic and Asian, from high-income areas, using Medicare and Medicaid, and morbidly obese (all P<.001). The mean length of stay (LOS), charges, and costs were decreased after GBR implementation (all P<.001). More patients were discharged routine and had fewer readmissions (both P<.001). There were fewer complications, including deep venous thromboses/pulmonary emboli, urinary tract infections, and blood transfusions (all P<.001). The difference-in-difference analyses suggested more females were discharged with home health care and had longer LOS than did males (both P<.001). The GBR appears to meet its main objective of cost reduction and improvements in quality of care. However, the proportion of females receiving TKA decreased, and their LOS did not improve as much as that of males. As other states consider global budgets, more research is needed to ensure this all-payer, rate-setting, capitated system does not cause decreased access to care. [Orthopedics. 2021;44(2):e266-e273.].


Assuntos
Artroplastia do Joelho/economia , Orçamentos/estatística & dados numéricos , Internacionalidade , Idoso , Bases de Dados Factuais , Feminino , Humanos , Pacientes Internados , Tempo de Internação/economia , Masculino , Medicaid/economia , Medicare/economia , Pessoa de Meia-Idade , Obesidade Mórbida/cirurgia , Alta do Paciente , Resultado do Tratamento , Estados Unidos
6.
SLAS Discov ; 24(7): 738-744, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31076010

RESUMO

The Caco-2 permeability assay is a well-accepted in vitro model to evaluate compounds' potential for oral absorption at early discovery. However, for many lipophilic compounds, no meaningful Caco-2 data could be generated due to their low solubility in assay buffer and/or poor recovery from the assay. In our previous study, we reported an organic catch approach to improve compound recovery. To further reduce compound loss and increase solubility in aqueous buffer, we explored the addition of bovine serum albumin (BSA). However, in contrast to the commonly used BSA level at 4%, a lower level of BSA was selected in an effort to minimize the potential risk of missing the identification of efflux substrates, and to avoid the extensive sample cleanup needed for 4% BSA. Through a systematic evaluation, it was found that 0.5% BSA was effective in enhancing compound solubility and reducing nonspecific binding, which allowed reliable assessment of the permeability and efflux potential for lipophilic compounds. Also, with an optimized sample handling process, no extra sample cleanup was required before liquid chromatography-mass spectrometry (LC-MS) analysis. The implementation of this assay has enabled accurate permeability assessment for compounds that had poor solubility and/or poor mass balance under the non-BSA assay conditions.


Assuntos
Permeabilidade da Membrana Celular , Descoberta de Drogas/métodos , Ensaios de Triagem em Larga Escala , Soroalbumina Bovina/metabolismo , Adsorção , Animais , Células CACO-2 , Bovinos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Cromatografia Líquida , Humanos , Espectrometria de Massas , Solubilidade
7.
Curr Alzheimer Res ; 14(4): 403-411, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28124585

RESUMO

INTRODUCTION: To date there is no cure for Alzheimer's disease (AD). After amyloid beta immunotherapies have failed to meet primary endpoints of slowing cognitive decline in AD subjects, the inhibition of the beta-secretase BACE1 appears as a promising therapeutic approach. Pre-clinical data obtained in APP23 mice suggested that the anti-cancer drug thalidomide decreases brainBACE1 and Aß levels. This prompted us to develop an NIH-supported Phase IIa clinical trial to test the potential of thalidomide for AD. We hypothesized that thalidomide can decrease or stabilize brain amyloid deposits, which would result in slower cognitive decline in drug- versus placebo-treated subjects. METHODS: This was a 24-week, randomized, double-blind, placebo-controlled, parallel group study with escalating dose regimen of thalidomide with a target dose of 400mg daily in patients with mild to moderate AD. The primary outcome measures were tolerability and cognitive performance assessed by a battery of tests. RESULTS: A total of 185 subjects have been pre-screened, out of which25 were randomized. Mean age of the sample at baseline was 73.64 (±7.20) years; mean education was 14.24 (±2.3) years; mean MMSE score was 21.00 (±5.32); and mean GDS score was 2.76 (±2.28).Among the 25 participants, 14 (56%) terminated early due to adverse events, dramatically decreasing the power of the study. In addition, those who completed the study (44%) never reached the estimated therapeutic dose of 400 mg/day thalidomide because of reported adverse events. The cognitive data showed no difference between the treated and placebo groups at the end of the trial. CONCLUSION: This study demonstrates AD patients have poor tolerability for thalidomide, and are unable to reach a therapeutic dose felt to be sufficient to have effects on BACE1. Because of poor tolerability, this study failed to demonstrate a beneficial effect on cognition.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Imunossupressores/efeitos adversos , Talidomida/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Cognição/efeitos dos fármacos , Método Duplo-Cego , Escolaridade , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Pacientes Desistentes do Tratamento , Talidomida/uso terapêutico , Falha de Tratamento
8.
Hum Mol Genet ; 24(16): 4625-35, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26002100

RESUMO

Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD-TDP) are two neurodegenerative disorders characterized by the accumulation of TDP-43. TDP-43 is proteolitically cleaved to generate two major C-terminal fragments of 35 and 25 kDa. The latter, known as TDP-25, is a consistent feature of FTLD-TDP and ALS; however, little is known about its role in disease pathogenesis. We have previously developed transgenic mice overexpressing low levels of TDP-25 (TgTDP-25(+/0)), which at 6 months of age show mild cognitive impairments and no motor deficits. To better understand the role of TDP-25 in the pathogenesis of ALS and FTLD-TDP, we generated TDP-25 homozygous mice (TgTDP-25(+/+)), thereby further increasing TDP-25 expression. We found a gene-dosage effect on cognitive and motor function at 15 months of age, as the TgTDP-25(+/+) showed more severe spatial and working memory deficits as well as worse motor performance than TgTDP-25(+/0) mice. These behavioral deficits were associated with increased soluble levels of TDP-25 in the nucleus and cytosol. Notably, high TDP-25 levels were also linked to reduced autophagy induction and proteasome function, two events that have been associated with both ALS and FTLD-TDP. In summary, we present strong in vivo evidence that high levels of TDP-25 are sufficient to cause behavioral deficits and reduce function of two of the major protein turnover systems: autophagy and proteasome. These mice represent a new tool to study the role of TDP-25 in the pathogenesis of ALS and FTLD-TDP.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Proteínas de Ligação a DNA/metabolismo , Degeneração Lobar Frontotemporal/metabolismo , Proteólise , Esclerose Lateral Amiotrófica/genética , Animais , Autofagia/genética , Comportamento Animal , Proteínas de Ligação a DNA/genética , Degeneração Lobar Frontotemporal/genética , Humanos , Camundongos , Camundongos Transgênicos , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Estrutura Terciária de Proteína
9.
J Neurosci Methods ; 223: 114-22, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24333289

RESUMO

BACKGROUND: A hallmark pathologic feature of Alzheimer's disease (AD) is accumulation of neuritic senile plaques in the brain parenchyma. Neurotoxic plaque cores are composed predominantly of amyloid-ß (Aß) peptides of 40 and 42 amino acids in length, formed by sequential cleavage of amyloid precursor protein (APP) by ß-, and γ-secretases. There is a great interest in approaches to modulate Aß peptide production and develop therapeutic interventions to reduce Aß levels to halt or slow the progression of neurodegeneration. NEW METHOD: We characterized and present the BE(2)-M17 human neuroblastoma cell line as a novel in vitro model of the APP-cleavage cascade to support future (1) functional studies of molecular regulators in Aß production, and (2) high-throughput screening assays of new pharmacotherapeutics. RESULTS: In BE(2)-M17 cells, both RNA (i.e., RT-PCR, RNA sequencing) and protein analyses (i.e., Western blots, ELISA), show endogenous expression of critical components of the amyloidogenic pathway, APP-cleavage intermediates CTF83 and CTF99, and final cleavage products Aß40 and Aß42. We further report effects of retinoic acid-mediated differentiation on morphology and gene expression in this cell line. COMPARISON WITH EXISTING METHOD(S): In contrast to primary isolates or other cell lines reported in current literature, BE(2)-M17 not only sustains baseline expression of the full contingent of APP-processing components, but also remains stably adherent during culture, facilitating experimental manipulations. CONCLUSIONS: Our evidence supports the use of BE(2)-M17 as a novel, human, cell-based model of the APP processing pathway that offers a potential streamlined approach to dissect molecular functions of endogenous regulatory pathways, and perform mechanistic studies to identify modulators of Aß production.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Modelos Biológicos , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/genética , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Ceratolíticos/farmacologia , Neuroblastoma/patologia , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Fatores de Tempo , Tretinoína/farmacologia
10.
Curr Alzheimer Res ; 10(3): 309-15, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23036023

RESUMO

The APOE genotype is a known susceptibility factor for Alzheimer's disease (AD). It is apparent that the presence of the APOE ε40 allele increases the risk for developing AD, lowers the age of onset in AD, and may influence the pathological burden seen in AD. In this study, we asked whether BACE1 levels differ by APOE genotype in the AD and non-demented (ND) brain. We isolated mid-frontal cortex (MFC) and mid-temporal cortex (MTC) from post-mortem ND and AD subjects that were APOE ε3/3, ε3/4, ε4/4 carriers. All AD subjects met NINDS-ADRDA and NIA-Reagan criteria for a diagnosis of AD. The MFC and MTC were homogenized and the lysates underwent ELISA and Western blotting for BACE1. The ELISA revealed that total BACE1 levels were lower in the MFC of AD compared to ND subjects. Furthermore, in APOE ε4 carriers BACE1 levels were lower than ε3/3 carriers in the ND frontal cortex. No difference in BACE1 levels was observed in AD MFC and in ND and AD MTC tissues. The ELISA results were confirmed by Western blotting. Our data suggest that brain BACEl levels may be influenced by the apolipoprotein E genotype before the onset of AD, providing an alternative explanation for the lower amyloid beta 42 levels in CSF in ND and AD subjects.


Assuntos
Doença de Alzheimer/enzimologia , Doença de Alzheimer/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Apolipoproteínas E/genética , Ácido Aspártico Endopeptidases/metabolismo , Encéfalo/enzimologia , Idoso , Idoso de 80 Anos ou mais , Secretases da Proteína Precursora do Amiloide/análise , Ácido Aspártico Endopeptidases/análise , Autopsia , Western Blotting , Ensaio de Imunoadsorção Enzimática , Feminino , Predisposição Genética para Doença/genética , Genótipo , Humanos , Masculino , Reação em Cadeia da Polimerase
11.
Platelets ; 24(3): 235-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22775589

RESUMO

To date there is no validated peripheral biomarker to assist with the clinical diagnosis of Alzheimer's disease (AD). Platelet proteins have been studied as AD biomarkers with relative success. In this study, we investigated whether platelet BACE1 levels differ between AD and cognitively normal (CN) control patients. Using a newly developed ELISA method, we found that BACE1 levels were significantly lower in AD compared to CN subjects. These data were supported by the observation that several BACE1 isoforms, identified by Western blotting, were also lower in AD platelets. This proof-of-concept study provides evidence for testing platelet BACE1 levels as a peripheral AD biomarker using a novel, sensitive and inexpensive method.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Plaquetas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Isoformas de Proteínas
12.
J Pharm Sci ; 101(8): 2755-62, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22611052

RESUMO

The Caco-2 cell culture system is widely employed as an in vitro model for prediction of intestinal absorption of test compounds in early drug discovery. Poor recovery is a commonly encountered issue in Caco-2 assay, which can lead to difficulty in data interpretation and underestimation of the apparent permeability of affected compounds. In this study, we systematically investigated the potential sources of compound loss in our automated, high-throughput Caco-2 assay, sample storage, and analysis processes, and as a result found the nonspecific binding to various plastic surfaces to be the major cause of poor compound recovery. To minimize the nonspecific binding, we implemented a simple and practical approach in our assay automation by preloading collection plates with organic solvent containing internal standard prior to transferring incubations samples. The implementation of this new method has been shown to significantly increase recovery in many compounds previously identified as having poor recovery in the Caco-2 permeability assay. With improved recovery, permeability results were obtained for many compounds that were previously not detected in the basolateral samples. In addition to recovery improvement, this new approach also simplified sample preparation for liquid chromatography-tandem mass spectrometric analysis and therefore achieved time and cost savings for the bioanalyst.


Assuntos
Permeabilidade da Membrana Celular , Ensaios de Triagem em Larga Escala/métodos , Espectrometria de Massas em Tandem/métodos , Células CACO-2 , Cromatografia Líquida/métodos , Humanos , Absorção Intestinal , Farmacocinética
13.
J Neurosci Methods ; 202(1): 70-6, 2011 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-21889954

RESUMO

The aspartyl protease BACE1 is the rate limiting enzyme in the synthesis of amyloid beta, which accumulation in the human brain is a hallmark of Alzheimer's disease (AD). BACE1 has been proposed as a surrogate marker of AD; however, very few BACE1 immunoassays have been reported. In the present study we have screened ten BACE1 antibodies by Western blot and several antibody pairs to develop a new BACE1 sandwich ELISA procedure. We identified one pair that showed little background and good reproducibility. Several dilution buffers and sample denaturation methods were tried to partially unfold BACE1 before capture. We found that dilution in PBS followed by 10 min incubation at 50°C critically improves the performance of the assay. Finally, we successfully measured BACE1 levels in a few human brain and platelet lysates as well as in plasma and AD CSF. We anticipate that this assay will lay the ground to accurately measure BACE1 levels in human tissues, which could facilitate the molecular diagnosis of AD in the near future.


Assuntos
Secretases da Proteína Precursora do Amiloide/análise , Ácido Aspártico Endopeptidases/análise , Ensaio de Imunoadsorção Enzimática/métodos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/enzimologia , Animais , Anticorpos , Especificidade de Anticorpos , Western Blotting , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
J Neurosci ; 30(21): 7326-34, 2010 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-20505099

RESUMO

As brain testosterone plays both androgenic and estrogenic actions due to its conversion into estrogen via aromatase naturally, it is unclear that the age-related reduction of testosterone increased risk of Alzheimer's disease (AD) in men is mediated through androgen alone or both androgen and estrogen mechanisms. Our previous studies using a gene-based approach in mouse model to block the conversion of testosterone into estrogen (aromatase gene knock-out, ArKO), found a depletion of estrogen and increase in testosterone endogenously in males. Here, we use crossing the ArKO mice with APP23 transgenic mice, a mouse model of AD, to produce APP23/Ar(+/-) mice to study the estrogen-independent effect of testosterone on AD. We found a significant reduction in brain plaque formation, improved cognitive function and increase NEP activity in male APP23/Ar(+/-) mice compared with age-matched male APP23 controls. In addition, we found, for the first time, a reduction of beta-secretase (BACE1) enzyme activity, mRNA level and protein expression in the male APP23/Ar(+/-) mice, suggesting that endogenous testosterone, independent from estrogen, may protect against AD in males via two major mechanisms, downregulation of BACE1 activities at transcriptional level to reduce beta amyloid production and upregulation of NEP activities to enhance bate amyloid degradation.


Assuntos
Doença de Alzheimer , Secretases da Proteína Precursora do Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/genética , Aromatase/genética , Ácido Aspártico Endopeptidases/metabolismo , Transtornos Cognitivos/etiologia , Regulação para Baixo/genética , Fatores Etários , Doença de Alzheimer/complicações , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Secretases da Proteína Precursora do Amiloide/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Aromatase/deficiência , Ácido Aspártico Endopeptidases/genética , Encéfalo/metabolismo , Encéfalo/patologia , Transtornos Cognitivos/genética , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática/métodos , Estrogênios/metabolismo , Comportamento Exploratório/fisiologia , Humanos , Insulisina/metabolismo , Masculino , Aprendizagem em Labirinto/fisiologia , Memória/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Neprilisina/metabolismo , Fosfopiruvato Hidratase/metabolismo , RNA Mensageiro/metabolismo , Radioimunoensaio/métodos , Estatísticas não Paramétricas , Testosterona/metabolismo
15.
J Appl Physiol (1985) ; 109(1): 68-78, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20431020

RESUMO

Immersion pulmonary edema (IPE) can occur in otherwise healthy swimmers and divers, likely because of stress failure of pulmonary capillaries secondary to increased pulmonary vascular pressures. Prior studies have revealed progressive increase in ventilation [minute ventilation (Ve)] during prolonged immersed exercise. We hypothesized that this increase occurs because of development of metabolic acidosis with concomitant rise in mean pulmonary artery pressure (MPAP) and that hyperoxia attenuates this increase. Ten subjects were studied at rest and during 16 min of exercise submersed at 1 atm absolute (ATA) breathing air and at 4.7 ATA in normoxia and hyperoxia [inspired P(O(2)) (Pi(O(2))) 1.75 ATA]. Ve increased from early (E, 6th minute) to late (L, 16th minute) exercise at 1 ATA (64.1 +/- 8.6 to 71.7 +/- 10.9 l/min BTPS; P < 0.001), with no change in arterial pH or Pco(2). MPAP decreased from E to L at 1 ATA (26.7 +/- 5.8 to 22.7 +/- 5.2 mmHg; P = 0.003). Ve and MPAP did not change from E to L at 4.7 ATA. Hyperoxia reduced Ve (62.6 +/- 10.5 to 53.1 +/- 6.1 l/min BTPS; P < 0.0001) and MPAP (29.7 +/- 7.4 to 25.1 +/- 5.7 mmHg, P = 0.002). Variability in MPAP among subjects was wide (range 14.1-42.1 mmHg during surface and depth exercise). Alveolar-arterial Po(2) difference increased from E to L in normoxia, consistent with increased lung water. We conclude that increased Ve at 1 ATA is not due to acidosis and is more consistent with respiratory muscle fatigue and that progressive pulmonary vascular hypertension does not occur during prolonged immersed exercise. Wide variation in MPAP among healthy subjects is consistent with variable individual susceptibility to IPE.


Assuntos
Hemodinâmica/fisiologia , Hiperóxia/fisiopatologia , Imersão/fisiopatologia , Edema Pulmonar/fisiopatologia , Ventilação Pulmonar/fisiologia , Natação/fisiologia , Adulto , Dióxido de Carbono/sangue , Mergulho/fisiologia , Exercício Físico/fisiologia , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Oxigênio/sangue , Consumo de Oxigênio/fisiologia , Pressão Parcial , Decúbito Ventral/fisiologia , Artéria Pulmonar/fisiologia , Capacidade Vital/fisiologia , Adulto Jovem
16.
J Hazard Mater ; 171(1-3): 1058-65, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19616380

RESUMO

A dynamic leaching test (DLT) was developed and used to evaluate the leaching of toxic substances for electronic waste in the environment. The major components in personal computers (PCs) including motherboards, hard disc drives, floppy disc drives, and compact disc drives were tested. The tests lasted for 2 years for motherboards and 1.5 year for the disc drives. The extraction fluids for the standard toxicity characteristic leaching procedure (TCLP) and synthetic precipitation leaching procedure (SPLP) were used as the DLT leaching solutions. A total of 18 elements including Ag, Al, As, Au, Ba, Be, Cd, Cr, Cu, Fe, Ga, Ni, Pd, Pb, Sb, Se, Sn, and Zn were analyzed in the DLT leachates. Only Al, Cu, Fe, Ni, Pb, and Zn were commonly found in the DLT leachates of the PC components. Their leaching levels were much higher in TCLP extraction fluid than in SPLP extraction fluid. The toxic heavy metal Pb was found to continuously leach out of the components over the entire test periods. The cumulative amounts of Pb leached out of the motherboards in TCLP extraction fluid reached 2.0 g per motherboard over the 2-year test period, and that in SPLP extraction fluid were 75-90% less. The leaching rates or levels of Pb were largely affected by the content of galvanized steel in the PC components. The higher was the steel content, the lower the Pb leaching rate would be. The findings suggest that the obsolete PCs disposed of in landfills or discarded in the environment continuously release Pb for years when subjected to landfill leachate or rains.


Assuntos
Eletrônica , Metais Pesados/análise , Microcomputadores , Eliminação de Resíduos/métodos , Poluentes do Solo/análise , Poluentes da Água/análise , Conservação dos Recursos Naturais , Monitoramento Ambiental , Poluentes Ambientais
17.
Org Lett ; 6(23): 4343-5, 2004 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-15524479

RESUMO

1,5-Cyclooctadiene can be stereoselectively transformed into a substituted bicyclo[3.3.0]octane ring system under palladium catalysis with concomitant formation of three carbon-carbon bonds. Reaction with an aryl iodide or triflate and malonate gives an exo-endo product, while the reaction with a malonate in the presence of oxygen affords a bis-endo adduct.

18.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 2330-3, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-17272196

RESUMO

Glaucoma and ocular hypertension are major causes of vision loss worldwide. Recent clinical studies have highlighted the importance of central corneal thickness in diagnosing these disorders. However, current instrumental methods of measuring corneal thickness are not ideal for widespread clinical deployment. Here we compare the existing state of the art in corneal pachymetry with a novel, simple optical technique that will allow for the use of corneal pachymetry as a diagnostic tool in a non-research clinical setting.

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