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1.
Nat Commun ; 15(1): 4448, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789460
2.
J Gerontol A Biol Sci Med Sci ; 77(1): 131-139, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33839788

RESUMO

BACKGROUND: Obesity exacerbates age-related effects on body composition and physical and metabolic function. Which exercise mode is most effective in mitigating these deleterious changes in dieting older adults with obesity is unknown. METHODS: In a randomized controlled trial, we performed a head-to-head comparison of aerobic (AEX), resistance (REX), or combination (COMB) exercise during matched ~10% weight loss in 160 obese older adults. Prespecified analyses compared 6-month changes in intermuscular adipose tissue (IMAT) and visceral adipose tissue (VAT) assessed using MRI, insulin sensitivity index (ISI) by oral glucose tolerance test, physical function using Modified Physical Performance Test (PPT), VO2peak, gait speed, and knee strength by dynamometry. RESULTS: IMAT and VAT decreased more in COMB than AEX and REX groups (IMAT; -41% vs -28% and -23% and VAT: -36% vs -19% and -21%; p = .003 to .01); IMAT and VAT decreased in all groups more than control (between-group p < .001). ISI increased more in COMB than AEX and REX groups (86% vs 50% and 39%; p = .005 to .03). PPT improved more in COMB than AEX and REX groups, while VO2peak improved more in COMB and AEX than REX group (all p < .05). Knee strength improved more in COMB and REX than AEX group (all p < .05). Changes in IMAT and VAT correlated with PPT (r = -0.28 and -0.39), VO2peak (r = -0.49 and -0.52), gait speed (r = -0.25 and -0.36), and ISI (r = -0.49 and -0.52; all p < .05). CONCLUSIONS: Weight loss plus combination aerobic and resistance exercise was most effective in improving ectopic fat deposition and physical and metabolic function in older adults with obesity.


Assuntos
Gordura Intra-Abdominal , Treinamento Resistido , Idoso , Exercício Físico , Humanos , Gordura Intra-Abdominal/metabolismo , Obesidade/metabolismo , Redução de Peso
3.
Ecol Appl ; 31(7): e02420, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34278638

RESUMO

Resource allocation for land acquisition is a common multiobjective problem that involves complex trade-offs. The National Wildlife Refuge System (NWRS) of the U.S. Fish and Wildlife Service currently uses the Targeted Resource Acquisition Comparison Tool (TRACT) to allocate funds from the Migratory Bird Conservation Fund (MBCF; established through the Migratory Bird Hunting and Conservation Act of 1934) for land acquisition based on cost-benefit analysis, regional priority rankings of candidate land parcels available for acquisition, and the overall biological contribution to duck population objectives. However, current policy encourages decision makers to consider societal and economic benefits of lands acquired, in addition to their biological benefits to waterfowl. These decisions about portfolio elements (i.e., individual land parcels) require an analysis of the difficult trade-offs among multiple objectives. In the last decade the application of multicriteria decision analysis (MCDA) methods has been instrumental in aiding decision makers with complex multiobjective decisions. In this study, we present an alternative approach to developing land-acquisition portfolios using MCDA and modern portfolio theory (MPT). We describe the development of a portfolio decision analysis tool using constrained optimization for land-acquisition decisions by the NWRS. We outline the decision framework, describe development of the prototype tool in Microsoft Excel, and test the results of the tool using land parcels submitted as candidates for MBCF funding in 2019. Our results indicate that the constrained optimization outperformed the traditional TRACT method and ad hoc portfolios developed using current NWRS criteria.


Assuntos
Animais Selvagens , Aves , Conservação dos Recursos Naturais , Animais , Análise Custo-Benefício
4.
Cell Metab ; 30(2): 261-273.e6, 2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31279675

RESUMO

Anabolic resistance and impaired myocellular quality contribute to age-related sarcopenia, which exacerbates with obesity. Diet-induced muscle mass loss is attenuated by resistance or aerobic plus resistance exercise compared to aerobic exercise in obese elderly. We assessed chronic effects of weight loss plus different exercise modalities on muscle protein synthesis response to feeding and myocellular quality. Obese older adults were randomized to a weight-management program plus aerobic, resistance, or combined aerobic and resistance exercise or to control. Participants underwent vastus lateralis biopsies at baseline and 6 months. Muscle protein synthesis rate increased more in resistance and combined than in control. Autophagy mediators' expression decreased more in combined than in aerobic, which experienced a higher increase in inflammation and mitochondrial regulators' expression. In obese elderly, combined aerobic and resistance exercise is superior to either mode independently for improving muscle protein synthesis and myocellular quality, thereby maintaining muscle mass during weight-loss therapy.


Assuntos
Exercício Físico , Proteínas Musculares/biossíntese , Músculo Esquelético/metabolismo , Obesidade/metabolismo , Treinamento Resistido , Idoso , Humanos , Redução de Peso
5.
Am J Transplant ; 19(7): 1941-1954, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30748092

RESUMO

Acute graft-versus-host disease (aGVHD) remains a barrier to the success of allogeneic hematopoietic stem cell transplantation (HSCT). Previously, we demonstrated that CC-chemokine receptor 7 (CCR7) is critical for aGVHD pathogenesis but dispensable for beneficial graft-versus-leukemia responses. As a result, we evaluated a fully human anti-CCR7-blocking antibody as a new approach to prevent aGVHD in preclinical models. Here we report that antibody R707 is able to block human CCR7 signaling and function in vitro in response to its 2 natural ligands. The antibody was less active against the murine orthologue, however, and failed to substantially limit aGVHD in a standard murine allogeneic HSCT model. Nevertheless, R707 significantly reduced xenogeneic aGVHD induced by human peripheral blood mononuclear cells (PBMCs). R707 limited CD4+ and in particular CD8+ T cell expansion during the period of antibody administration. These effects were transient, however, and T cell numbers recovered after antibody cessation. R707 did not substantially impair the antitumor potential of the PBMC inoculum as antibody-treated mice retained their capacity to reject a human acute myeloid leukemia cell line. Collectively, these data indicate for the first time that an antibody directed against CCR7 might represent a viable new approach for aGVHD prevention.


Assuntos
Anticorpos Monoclonais/farmacologia , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/prevenção & controle , Leucócitos Mononucleares/imunologia , Receptores CCR7/imunologia , Linfócitos T/imunologia , Doença Aguda , Animais , Anticorpos Monoclonais/imunologia , Doença Enxerto-Hospedeiro/genética , Transplante de Células-Tronco Hematopoéticas , Xenoenxertos , Humanos , Camundongos , Receptores CCR7/genética , Linfócitos T/transplante , Doadores de Tecidos , Transplante Homólogo
6.
Biol Blood Marrow Transplant ; 25(6): 1062-1074, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30668984

RESUMO

Despite recent advances in therapy, allogeneic hematopoietic stem cell transplantation (HSCT) remains the only curative option for a range of high-risk hematologic malignancies. However, acute graft-versus-host disease (aGVHD) continues to limit the long-term success of HSCT, and new therapies are still needed. We previously demonstrated that aGVHD depends on the ability of donor conventional T cells (Tcons) to express the lymph node trafficking receptor, CC-Chemokine Receptor 7 (CCR7). Consequently, we examined the ability of cosalane, a recently identified CCR7 small-molecule antagonist, to attenuate aGVHD in mouse HSCT model systems. Here we show that the systemic administration of cosalane to transplant recipients after allogeneic HSCT did not prevent aGVHD. However, we were able to significantly reduce aGVHD by briefly incubating donor Tcons with cosalane ex vivo before transplantation. Cosalane did not result in Tcon toxicity and did not affect their activation or expansion. Instead, cosalane prevented donor Tcon trafficking into host secondary lymphoid tissues very early after transplantation and limited their subsequent accumulation within the liver and colon. Cosalane did not appear to impair the intrinsic ability of donor Tcons to produce inflammatory cytokines. Furthermore, cosalane-treated Tcons retained their graft-versus-leukemia (GVL) potential and rejected a murine P815 inoculum after transplantation. Collectively, our data indicate that a brief application of cosalane to donor Tcons before HSCT significantly reduces aGVHD in relevant preclinical models while generally sparing beneficial GVL effects, and that cosalane might represent a viable new approach for aGVHD prophylaxis.


Assuntos
Ácido Aurintricarboxílico/análogos & derivados , Doença Enxerto-Hospedeiro/genética , Efeito Enxerto vs Leucemia/genética , Transplante de Células-Tronco Hematopoéticas/métodos , Receptores CCR7/metabolismo , Linfócitos T/metabolismo , Condicionamento Pré-Transplante/métodos , Doença Aguda , Animais , Ácido Aurintricarboxílico/farmacologia , Ácido Aurintricarboxílico/uso terapêutico , Humanos , Camundongos , Doadores de Tecidos
7.
Blood Adv ; 2(18): 2307-2319, 2018 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-30228128

RESUMO

Chronic graft-versus-host disease (cGVHD) causes significant morbidity and mortality in patients after allogeneic bone marrow (BM) or stem cell transplantation (allo-SCT). Recent work has indicated that both T and B lymphocytes play an important role in the pathophysiology of cGVHD. Previously, our group showed a critical role for the germinal center response in the function of B cells using a bronchiolitis obliterans (BO) model of cGVHD. Here, we demonstrated for the first time that cGVHD is associated with severe defects in the generation of BM B lymphoid and uncommitted common lymphoid progenitor cells. We found an increase in the number of donor CD4+ T cells in the BM of mice with cGVHD that was negatively correlated with B-cell development and the frequency of osteoblasts and Prrx-1-expressing perivascular stromal cells, which are present in the B-cell niche. Use of anti-DR3 monoclonal antibodies to enhance the number of donor regulatory T cells (Tregs) in the donor T-cell inoculum ameliorated the pathology associated with BO in this model. This correlated with an increased number of endosteal osteoblastic cells and significantly improved the generation of B-cell precursors in the BM after allo-SCT. Our work indicates that donor Tregs play a critical role in preserving the generation of B-cell precursors in the BM after allo-SCT. Approaches to enhance the number and/or function of donor Tregs that do not enhance conventional T-cell activity may be important to decrease the incidence and severity of cGVHD in part through normal B-cell lymphopoiesis.


Assuntos
Linfócitos B/imunologia , Células da Medula Óssea/imunologia , Bronquiolite Obliterante/etiologia , Diferenciação Celular , Doença Enxerto-Hospedeiro/etiologia , Animais , Linfócitos B/metabolismo , Biomarcadores , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Bronquiolite Obliterante/patologia , Bronquiolite Obliterante/fisiopatologia , Diferenciação Celular/imunologia , Doença Crônica , Citocinas/metabolismo , Modelos Animais de Doenças , Expressão Gênica , Doença Enxerto-Hospedeiro/patologia , Imunofenotipagem , Depleção Linfocítica , Camundongos , Camundongos Transgênicos , Osteoblastos/imunologia , Osteoblastos/metabolismo , Células Precursoras de Linfócitos B/citologia , Células Precursoras de Linfócitos B/imunologia , Células Precursoras de Linfócitos B/metabolismo , Índice de Gravidade de Doença , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
8.
Biol Blood Marrow Transplant ; 24(11): 2184-2189, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29981461

RESUMO

Acute graft-versus-host disease (aGVHD) remains a barrier to the success of allogeneic hematopoietic stem cell transplantation. In mice, studies have demonstrated that donor conventional T cells traffic into host secondary lymphoid tissues early after transplant, and that this process is critical for the development of disease. As a result, the measurement of cellular proliferation within lymphoid sites early after transplant might be a useful approach for predicting aGVHD in humans. 18F-3'-deoxy-3'-fluorothymidine (FLT) positron emission tomography (PET) imaging has recently emerged as a functional imaging modality in oncology patients. FLT, a thymidine analog, is incorporated into replicating DNA and is thus an indirect marker of cellular proliferation. Here we report that FLT PET imaging can differentiate mice receiving alloreactive T cells and destined to develop lethal aGVHD from control mice. Mice receiving allogeneic T cells demonstrated a stronger FLT signal within the peripheral lymph nodes compared with control mice at all time points after transplant. In addition, allogeneic T cell recipients transiently demonstrated stronger FLT uptake within the spleen. Importantly, these differences were apparent before the development of clinical disease. In contrast, the FLT signal within the host bowel, an important aGVHD target organ, was more variable after transplant and was not consistently different between aGVHD mice and control mice. Collectively, these findings suggest that the imaging of patient lymphoid sites using existing FLT PET technology might be useful for predicting aGVHD in the clinical setting.


Assuntos
Fluordesoxiglucose F18/uso terapêutico , Doença Enxerto-Hospedeiro/diagnóstico por imagem , Transplante de Células-Tronco Hematopoéticas/métodos , Tomografia por Emissão de Pósitrons/métodos , Condicionamento Pré-Transplante/métodos , Doença Aguda , Animais , Modelos Animais de Doenças , Doença Enxerto-Hospedeiro/patologia , Camundongos
9.
SLAS Discov ; 23(10): 1083-1091, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29958052

RESUMO

CC-chemokine receptor 7 (CCR7) is a G protein-coupled receptor expressed on a variety of immune cells. CCR7 plays a critical role in the migration of lymphocytes into secondary lymphoid tissues. CCR7 expression, however, has been linked to numerous disease states. Due to its therapeutic relevance and absence of available CCR7 inhibitors, we undertook a high-throughput screen (HTS) to identify small-molecule antagonists of the receptor. Here, we describe a robust HTS approach using a commercially available ß-galactosidase enzyme fragment complementation system and confirmatory transwell chemotaxis assays. This work resulted in the identification of several compounds with activity against CCR7. The most potent of these was subsequently determined to be cosalane, a cholesterol derivative previously designed as a therapeutic for human immunodeficiency virus. Cosalane inhibited both human and murine CCR7 in response to both CCL19 and CCL21 agonists at physiologic concentrations. Furthermore, cosalane produced durable inhibition of the receptor following a cellular incubation period with subsequent washout. Overall, our work describes the development of an HTS-compatible assay, completion of a large HTS campaign, and demonstration for the first time that cosalane is a validated CCR7 antagonist. These efforts could pave the way for new approaches to address CCR7-associated disease processes.


Assuntos
Ácido Aurintricarboxílico/análogos & derivados , Ensaios de Triagem em Larga Escala , Receptores CCR7/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Animais , Ácido Aurintricarboxílico/química , Ácido Aurintricarboxílico/farmacologia , Linhagem Celular , Quimiotaxia/efeitos dos fármacos , Desenho de Fármacos , Humanos , Ligantes , Camundongos , Estrutura Molecular , Receptores CCR7/química , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/química , Relação Estrutura-Atividade , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo
10.
Biol Blood Marrow Transplant ; 23(4): 569-580, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28161607

RESUMO

Idiopathic pneumonia syndrome (IPS) is a noninfectious inflammatory disorder of the lungs that occurs most often after fully myeloablative allogeneic hematopoietic stem cell transplantation (HSCT). IPS can be severe and is associated with high 1-year mortality rates despite existing therapies. The canonical nuclear factor-(NF) κB signaling pathway has previously been linked to several inflammatory disorders of the lung, including asthma and lung allograft rejection. It has never been specifically targeted as a novel IPS treatment approach, however. Here, we report that the IκB kinase 2 (IKK2) antagonist BAY 65-5811 or "compound A," a highly potent and specific inhibitor of the NF-κB pathway, was able to improve median survival times and recipient oxygenation in a well-described mouse model of IPS. Compound A impaired the production of the proinflammatory chemokines CCL2 and CCL5 within the host lung after transplantation. This resulted in significantly lower numbers of donor lung infiltrating CD4+ and CD8+ T cells and reduced pulmonary inflammatory cytokine production after allograft. Compound A's beneficial effects appeared to be specific for limiting pulmonary injury, as the drug was unable to improve outcomes in a B6 into B6D2 haplotype-matched murine HSCT model in which recipient mice succumb to lethal acute graft-versus-host disease of the gastrointestinal tract. Collectively, our data suggest that the targeting of the canonical NF-κB pathway with a small molecule IKK2 antagonist may represent an effective and novel therapy for the specific management of acute lung injury that can occur after allogeneic HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Quinase I-kappa B/antagonistas & inibidores , Lesão Pulmonar/tratamento farmacológico , Terapia de Alvo Molecular/métodos , NF-kappa B/metabolismo , Pneumonia/tratamento farmacológico , Animais , Lesão Pulmonar/etiologia , Camundongos , Resultado do Tratamento
11.
Eur J Endocrinol ; 173(2): 167-74, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26142101

RESUMO

OBJECTIVE: Because the aromatase enzyme catalyzes the conversion of testosterone to estradiol (E2), the activity of this enzyme could be important in the musculoskeletal health of men with low testosterone. The objective of the present study is to determine the influence of aromatase activity on the bone mineral density (BMD) and body composition of patients with hypogonadism. DESIGN: Cross-sectional study. METHODS: The baseline data of 90 patients between 40 and 74 years old who participated in a genetic study of response to testosterone therapy in men with low testosterone (i.e., <300 ng/dl) were analyzed. BMD and body composition were measured by dual-energy X-ray absorptiometry. Serum testosterone was measured by automated immunoassay, E2 was measured by ultrasensitive enzyme immunoassay, and sex hormone-binding globulin was measured by enzyme immunoassay. RESULTS: Men in the highest tertile of E2 to testosterone ratio (E2:T) had the highest spine BMD (P ≤ 0.037), highest truncal fat (P=0.046), and lowest truncal lean body mass (P=0.045). A similar pattern was observed in the upper extremities; that is, fat mass significantly increased (P=0.047), whereas lean mass significantly decreased (P=0.034) with increasing E2:T tertiles. CONCLUSION: The present findings suggest that in men with hypogonadism, aromatase activity could be an important determinant of musculoskeletal health. Men with high aromatase activity are able to maintain a higher BMD despite low circulating testosterone, but they have lower lean and higher truncal fat mass as compared to those with lower aromatase activity.


Assuntos
Gordura Abdominal/metabolismo , Aromatase/sangue , Índice de Massa Corporal , Densidade Óssea/fisiologia , Hipogonadismo/sangue , Adulto , Idoso , Biomarcadores/sangue , Composição Corporal/fisiologia , Estudos Transversais , Ativação Enzimática/fisiologia , Humanos , Hipogonadismo/diagnóstico , Masculino , Pessoa de Meia-Idade
12.
Int J Endocrinol ; 2014: 507395, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25165472

RESUMO

In this study, we evaluated the independent and combined effects of baseline circulating gonadal, anabolic hormones and adipokines on physical function in 107 frail, obese (BMI ≥ 30 kg/m(2)), and older (≥65 yr) subjects. Our results showed significant positive correlations between circulating testosterone and insulin growth factor-1 (IGF-1) with knee flexion, knee extension, one-repetition maximum (1-RM), and peak oxygen consumption (VO2 peak), while no correlation was observed with estradiol. Among the adipokines, high sensitivity C-reactive protein (Hs-CRP) and leptin negatively correlated with the modified physical performance testing (PPT), knee flexion, knee extension, 1-RM, and VO2 peak. Interleukin-6 ( Il-6) negatively correlated with knee flexion and VO2 peak and soluble tumor necrosis factors receptor-1 (sTNFr1) correlated with PPT, 1-RM, and VO2 peak. Adiponectin correlated negatively with 1-RM. Multiple regression analysis revealed that, for PPT, sTNFr1 was the only independent predictor. Independent predictors included adiponectin, leptin, and testosterone for knee flexion; leptin and testosterone for knee extension; adiponectin, leptin, and testosterone for 1-RM; and IGF-1, IL-6, leptin, and testosterone for VO2 peak. In conclusion, in frail obese older adults, circulating levels of testosterone, adiponectin, and leptin appear to be important predictors of physical strength and fitness, while inflammation appears to be a major determinant of physical frailty.

13.
Blood ; 122(5): 825-36, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23798714

RESUMO

The infusion of donor regulatory T cells (Tregs) has been used to prevent acute graft-versus-host disease (GVHD) in mice and has shown promise in phase 1 clinical trials. Previous work suggested that early Treg migration into lymphoid tissue was important for GVHD prevention. However, it is unclear how and where Tregs function longitudinally to affect GVHD. To better understand their mechanism of action, we studied 2 Treg-associated chemokine receptors in murine stem cell transplant models. CC chemokine receptor (CCR) 4 was dispensable for donor Treg function in the transplant setting. Donor Tregs lacking CCR8 (CCR8(-/-)), however, were severely impaired in their ability to prevent lethal GVHD because of increased cell death. By itself, CCR8 stimulation was unable to rescue Tregs from apoptosis. Instead, CCR8 potentiated Treg survival by promoting critical interactions with dendritic cells. In vivo, donor bone marrow-derived CD11c(+) antigen-presenting cells (APCs) were important for promoting donor Treg maintenance after transplant. In contrast, host CD11c(+) APCs appeared to be dispensable for early activation and expansion of donor Tregs. Collectively, our data indicate that a sustained donor Treg presence is critical for their beneficial properties, and that their survival depends on CCR8 and donor but not host CD11c(+) APCs.


Assuntos
Doença Enxerto-Hospedeiro/genética , Doença Enxerto-Hospedeiro/prevenção & controle , Receptores CCR8/fisiologia , Linfócitos T Reguladores/fisiologia , Animais , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Células Apresentadoras de Antígenos/fisiologia , Antígeno CD11c/metabolismo , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Células Cultivadas , Sobrevivência de Enxerto/genética , Sobrevivência de Enxerto/imunologia , Doença Enxerto-Hospedeiro/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Transgênicos , Receptores CCR8/genética , Receptores CCR8/metabolismo , Linfócitos T Reguladores/metabolismo , Doadores de Tecidos
14.
J Pharmacol Exp Ther ; 334(1): 106-15, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20406857

RESUMO

Elevated apolipoprotein E (apoE) synthesis within crushed sciatic nerves advocates that apoE could benefit axonal repair and reconstruction of axonal and myelin membranes. We created an apoE-mimetic peptide, COG112 (acetyl-RQIKIWFQNRRMKWKKCLRVRLASHLRKLRKRLL-amide), and found that postinjury treatment with COG112 significantly improved recovery of motor and sensory function following sciatic nerve crush in C57BL/6 mice. Morphometric analysis of injured sciatic nerves revealed that COG112 promoted axonal regrowth after 2 weeks of treatment. More strikingly, the thickness of myelin sheaths was increased by COG112 treatment. Consistent with these histological findings, COG112 potently elevated growth associated protein 43 (GAP-43) and peripheral myelin protein zero (P0), which are markers of axon regeneration and remyelination, respectively. Electron microscopic examination further suggested that the apoE-mimetic COG112 may increase clearance of myelin debris. Schwann cell uptake of cholesterol-containing low-density lipoprotein particles was selectively enhanced by COG112 treatment in a Schwann cell line S16. Moreover, COG112 significantly promoted axon elongation in primary dorsal root ganglion cultures from rat pups. Considering that cholesterol and lipids are needed for reconstructing myelin sheaths and axon extension, these data support a hypothesis where supplementation with exogenous apoE-mimetics such as COG112 may be a promising strategy for restoring lost functional and structural elements following nerve injury.


Assuntos
Apolipoproteínas E/química , Axônios/efeitos dos fármacos , Bainha de Mielina/metabolismo , Regeneração Nervosa/efeitos dos fármacos , Peptídeos/uso terapêutico , Nervo Isquiático/lesões , Neuropatia Ciática/tratamento farmacológico , Sequência de Aminoácidos , Animais , Apolipoproteínas E/metabolismo , Axônios/metabolismo , Western Blotting , Modelos Animais de Doenças , Feminino , Lipoproteínas LDL/metabolismo , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Compressão Nervosa , Fibras Nervosas Mielinizadas/efeitos dos fármacos , Fibras Nervosas Mielinizadas/metabolismo , Peptídeos/administração & dosagem , Peptídeos/química , Peptídeos/farmacologia , Ratos , Células de Schwann , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/ultraestrutura , Neuropatia Ciática/metabolismo , Resultado do Tratamento , Caminhada
15.
Biol Bull ; 211(3): 208-11, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17179380

RESUMO

Many marine organisms spend the early part of their lives as larvae suspended in the water column before metamorphosing into benthic reproductive adults. Metamorphosis does not occur until a larva has become competent to respond to appropriate stimuli and after a suitable habitat for the young juvenile has been encountered. The gaseous neurotransmitter nitric oxide is thought to be important in the regulation of metamorphosis by holding the organism in the larval state. We have investigated expression of the neuronal nitric oxide synthase (nNOS) gene in larval and metamorphosing individuals of the marine mud snail Ilyanassa obsoleta. Our results indicate that nNOS is expressed at constant levels throughout larval development. In contrast, expression of nNOS decreases markedly during the first 24 h of metamorphosis. Our observations support previous findings that demonstrate that nitric oxide is present in larvae though competence. The decrease in nNOS gene expression that occurs during metamorphosis corresponds with a previously described reduction in nNOS activity.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Óxido Nítrico Sintase Tipo I/genética , Caramujos/crescimento & desenvolvimento , Sequência de Aminoácidos , Animais , Apoptose , Sistema Nervoso Central/anatomia & histologia , Sistema Nervoso Central/citologia , Sistema Nervoso Central/enzimologia , DNA Complementar , Regulação para Baixo , Larva/enzimologia , Larva/genética , Dados de Sequência Molecular , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase , Óxido Nítrico Sintase Tipo I/química , Alinhamento de Sequência , Transdução de Sinais , Caramujos/enzimologia , Caramujos/genética
16.
Int J Geriatr Psychiatry ; 20(7): 623-8, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16021654

RESUMO

BACKGROUND: Cholinesterase inhibitors are used to treat mild to moderate Alzheimer's disease. Their role in patients with concurrent cerebrovascular disease has been less well studied, and the influence of vascular risk factors on response to treatment is uncertain. We investigated the effect of hypertension and white matter lesions (WML) on response. METHODS: A retrospective sample of 160 consecutive out-patients who had blood pressure measured and the presence or absence of WML recorded at baseline and who completed six months treatment with a cholinesterase inhibitor was studied. Subjects scored either zero or one on the Modified Hachinski Ischaemic Scale. Subjects were assessed using the Mini-Mental State Examination (MMSE), the Digit Symbol Substitution test (DSST) and both the Instrumental Activities of Daily Living (IADL) and Social Behaviour (SB) sub-scales of the Nurses Observation Scale for Geriatric Patients (NOSGER). RESULTS: 43.9% of the total study population were classified as good responders using our criteria. Neither the presence of hypertension nor the presence of WML alone influenced outcome. However, there was a statistically significant interaction between blood pressure and WML on outcome variables on multiple analysis of variance (MANOVA) (F(4, 139) = 5.60, p < 0.0005). Subjects with both hypertension and WML deteriorate to a significantly greater extent in IADL and SB scores than any other group (p < 0.05 in each case). This effect could not be explained by age or by smoking status. CONCLUSION: Our results support the hypothesis that there is an interaction between hypertension and WML that adversely influences functional change during cholinesterase inhibitor treatment. Our results are a contrast to suggestions that subjects with vascular disease show a better response to cholinesterase inhibitors. We recommend careful exploration of factors that may influence outcome.


Assuntos
Doença de Alzheimer/complicações , Doença de Alzheimer/tratamento farmacológico , Encéfalo/patologia , Inibidores da Colinesterase/uso terapêutico , Hipertensão/complicações , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Feminino , Avaliação Geriátrica/métodos , Humanos , Hipertensão/patologia , Masculino , Testes Neuropsicológicos , Prognóstico , Escalas de Graduação Psiquiátrica , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
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