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1.
Proc Natl Acad Sci U S A ; 120(16): e2220557120, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37040417

RESUMO

The mature HIV-1 capsid protects the viral genome and interacts with host proteins to travel from the cell periphery into the nucleus. To achieve this, the capsid protein, CA, constructs conical capsids from a lattice of hexamers and pentamers, and engages in and then relinquishes multiple interactions with cellular proteins in an orchestrated fashion. Cellular host factors including Nup153, CPSF6, and Sec24C engage the same pocket within CA hexamers. How CA assembles pentamers and hexamers of different curvatures, how CA oligomerization states or curvature might modulate host-protein interactions, and how binding of multiple cofactors to a single site is coordinated, all remain to be elucidated. Here, using single-particle cryoEM, we have determined the structure of the mature HIV-1 CA pentamer and hexamer from conical CA-IP6 polyhedra to ~3 Å resolution. We also determined structures of hexamers in the context of multiple lattice curvatures and number of pentamer contacts. Comparison of these structures, bound or not to host protein peptides, revealed two structural switches within HIV-1 CA that modulate peptide binding according to CA lattice curvature and whether CA is hexameric or pentameric. These observations suggest that the conical HIV-1 capsid has different host-protein binding properties at different positions on its surface, which may facilitate cell entry and represent an evolutionary advantage of conical morphology.


Assuntos
Capsídeo , HIV-1 , Capsídeo/metabolismo , Proteínas do Capsídeo/química , HIV-1/genética , Ligação Proteica , Citoplasma/metabolismo
2.
Occup Environ Med ; 2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35738891

RESUMO

OBJECTIVES: To use industry-specific denominators to more accurately examine trends in prevalence rates for occupational cases of elevated blood lead levels (eBLLs) in Pennsylvania. METHODS: We used adult (aged ≥16 years) blood lead level data from Pennsylvania (2007-2018) and industry-specific denominator data from the US Census Bureau's County Business Patterns to calculate prevalence rates for eBLLs, defined as ≥25 µg/dL. RESULTS: Of the 19 904 cases with eBLLs, 92% were due to occupational lead exposure, with 83% from workers in the battery manufacturing industry. In 2018, the prevalence rate of eBLLs for battery manufacturing (8036.4 cases per 100 000 employed battery manufacturing workers) was 543 times the overall Pennsylvania prevalence rate. The prevalence rate for battery manufacturing steeply declined 71% from 2007 to 2018. CONCLUSIONS: The battery manufacturing industry had the highest burden of occupational lead exposure in Pennsylvania, illustrating the importance of using industry-specific denominators to accurately identify sources of lead exposure. Although the prevalence rate of eBLLs declined over time, lead exposure remains a major concern among battery manufacturing workers.

3.
Nature ; 588(7838): 498-502, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32805734

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virions are surrounded by a lipid bilayer from which spike (S) protein trimers protrude1. Heavily glycosylated S trimers bind to the angiotensin-converting enzyme 2 receptor and mediate entry of virions into target cells2-6. S exhibits extensive conformational flexibility: it modulates exposure of its receptor-binding site and subsequently undergoes complete structural rearrangement to drive fusion of viral and cellular membranes2,7,8. The structures and conformations of soluble, overexpressed, purified S proteins have been studied in detail using cryo-electron microscopy2,7,9-12, but the structure and distribution of S on the virion surface remain unknown. Here we applied cryo-electron microscopy and tomography to image intact SARS-CoV-2 virions and determine the high-resolution structure, conformational flexibility and distribution of S trimers in situ on the virion surface. These results reveal the conformations of S on the virion, and provide a basis from which to understand interactions between S and neutralizing antibodies during infection or vaccination.


Assuntos
Microscopia Crioeletrônica , SARS-CoV-2/metabolismo , SARS-CoV-2/ultraestrutura , Glicoproteína da Espícula de Coronavírus/análise , Glicoproteína da Espícula de Coronavírus/ultraestrutura , Vírion/química , Vírion/ultraestrutura , Anticorpos Neutralizantes/imunologia , COVID-19/imunologia , Vacinas contra COVID-19/imunologia , Linhagem Celular Tumoral , Humanos , Modelos Moleculares , Maleabilidade , Conformação Proteica , Multimerização Proteica , SARS-CoV-2/química , SARS-CoV-2/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/isolamento & purificação , Vírion/isolamento & purificação , Vírion/metabolismo
4.
JACC Basic Transl Sci ; 4(2): 161-172, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31061918

RESUMO

Mice were treated with a fully human monoclonal glucagon receptor antagonistic antibody REMD2.59 following myocardial infarction or pressure overload. REMD2.59 treatment blunted cardiac hypertrophy and fibrotic remodeling, and attenuated contractile dysfunction at 4 weeks after myocardial infarction. In addition, REMD2.59 treatment at the onset of pressure overload significantly suppressed cardiac hypertrophy and chamber dilation with marked preservation of cardiac systolic and diastolic function. Initiation of REMD2.59 treatment 2 weeks after pressure overload significantly blunted the progression of cardiac pathology. These results provide the first in vivo proof-of-concept evidence that glucagon receptor antagonism is a potentially efficacious therapy to ameliorate both onset and progression of heart failure.

5.
J Occup Environ Hyg ; 16(7): 477-488, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31112485

RESUMO

Tris(1-chloro-2-propyl) phosphate (TCPP, also referenced as TCIPP), a flame retardant used in spray polyurethane foam insulation, increases cell toxicity and affects fetal development. Spray polyurethane foam workers have the potential to be exposed to TCPP during application. In this study, we determined exposure to TCPP and concentrations of the urinary biomarker bis(1-chloro-2-propyl) phosphate (BCPP) among 29 spray polyurethane foam workers over 2 work days. Work was conducted at residential or commercial facilities using both open-cell (low density) and closed-cell (high density) foam. Study participants provided two personal air samples (Day 1 and Day 2), two hand wipe samples (Pre-shift Day 2 and Post-shift Day 2), and two spot urine samples (Pre-shift Day 1 and Post-shift Day 2). Bulk samples of cured spray foam were also analyzed. Sprayers were found to have significantly higher TCPP geometric mean (GM) concentration in personal air samples (87.1 µg/m3), compared to helpers (30.2 µg/m3; p = 0.025). A statistically significant difference was observed between TCPP pre- and post-shift hand wipe GM concentrations (p = 0.004). Specifically, TCPP GM concentration in post-shift hand wipe samples of helpers (106,000 ng/sample) was significantly greater than pre-shift (27,300 ng/sample; p < 0.001). The GM concentration of the urinary biomarker BCPP (23.8 µg/g creatinine) was notably higher than the adult male general population (0.159 µg/g creatinine, p < 0.001). Urinary BCPP GM concentration increased significantly from Pre-shift Day 1 to Post-shift Day 2 for sprayers (p = 0.013) and helpers (p = 0.009). Among bulk samples, cured open-cell foam had a TCPP GM concentration of 9.23% by weight while closed-cell foam was 1.68%. Overall, post-shift BCPP urine concentrations were observed to be associated with TCPP air and hand wipe concentrations, as well as job position (sprayer vs. helper). Spray polyurethane foam workers should wear personal protective equipment including air-supplied respirators, coveralls, and gloves during application.


Assuntos
Poluentes Ocupacionais do Ar/análise , Retardadores de Chama/análise , Exposição Ocupacional/análise , Compostos Organofosforados/análise , Adulto , Poluentes Ocupacionais do Ar/urina , Biomarcadores/urina , Monitoramento Ambiental , Mãos , Humanos , Masculino , Compostos Organofosforados/urina , Equipamento de Proteção Individual/estatística & dados numéricos , Poliuretanos
6.
Urology ; 122: 133-138, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30201301

RESUMO

OBJECTIVE: To evaluate the performance of a rapid, low cost, noncontrast MRI examination as a secondary screening tool in detection of clinically significant prostate cancer. METHODS: In this prospective single institution study, 129 patients with elevated prostate-specific antigen levels or abnormal digital rectal examination findings underwent MRI with an abbreviated biparamatric MRI protocol consisting of high-resolution axial T2- and diffusion-weighted images. Index lesions were classified according to modified Prostate Imaging - Reporting and Data System (mPI-RADS) version 2.0. All patients underwent standard transrectal ultrasound-guided biopsy after MRI with the urologist being blinded to MRI results. Subsequently, all patients with suspicious lesions (mPI-RADS 3, 4, or 5) underwent cognitively guided targeted biopsy after discussion of MRI results with the urologist. Sensitivity and negative predictive value for identification of clinically significant prostate cancer (Gleason score 3+4 and above) were determined. RESULTS: Rapid biparametric MRI discovered 176 lesions identified in 129 patients. Rapid MRI detected clinically significant cancers with a sensitivity of 95.1% with a negative predictive value of 95.1% and positive predictive value of 53.2%, leading to a change in management in 10.8% of the patients. False negative rate of biparametric (bp) MRI was 4.7%. CONCLUSION: We found that a bp-MRI examination can detect clinically significant lesions and changed patient management in 10.8% of the patients. A rapid MRI protocol can be used as a useful secondary screening tool in men presenting with suspicion of prostate cancer.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico , Idoso , Análise Custo-Benefício , Imagem de Difusão por Ressonância Magnética/economia , Exame Retal Digital , Reações Falso-Negativas , Humanos , Biópsia Guiada por Imagem , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Valor Preditivo dos Testes , Estudos Prospectivos , Próstata/patologia , Antígeno Prostático Específico , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Sensibilidade e Especificidade , Fatores de Tempo , Ultrassonografia de Intervenção
7.
Cell Rep ; 22(7): 1760-1773, 2018 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-29444429

RESUMO

The antidiabetic potential of glucagon receptor antagonism presents an opportunity for use in an insulin-centric clinical environment. To investigate the metabolic effects of glucagon receptor antagonism in type 2 diabetes, we treated Leprdb/db and Lepob/ob mice with REMD 2.59, a human monoclonal antibody and competitive antagonist of the glucagon receptor. As expected, REMD 2.59 suppresses hepatic glucose production and improves glycemia. Surprisingly, it also enhances insulin action in both liver and skeletal muscle, coinciding with an increase in AMP-activated protein kinase (AMPK)-mediated lipid oxidation. Furthermore, weekly REMD 2.59 treatment over a period of months protects against diabetic cardiomyopathy. These functional improvements are not derived simply from correcting the systemic milieu; nondiabetic mice with cardiac-specific overexpression of lipoprotein lipase also show improvements in contractile function after REMD 2.59 treatment. These observations suggest that hyperglucagonemia enables lipotoxic conditions, allowing the development of insulin resistance and cardiac dysfunction during disease progression.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Glucose/metabolismo , Coração/fisiopatologia , Receptores de Glucagon/antagonistas & inibidores , Adenilato Quinase/metabolismo , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/enzimologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Cardiomiopatias Diabéticas/complicações , Cardiomiopatias Diabéticas/patologia , Cardiomiopatias Diabéticas/prevenção & controle , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , Gluconeogênese/efeitos dos fármacos , Teste de Tolerância a Glucose , Hiperglicemia/complicações , Hiperglicemia/metabolismo , Hiperglicemia/patologia , Insulina/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipídeos/toxicidade , Fígado/metabolismo , Camundongos , Receptores de Glucagon/metabolismo
8.
Clin Trials ; 15(1): 36-43, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28795584

RESUMO

BACKGROUND/AIMS: Reproducible outcomes in clinical trials depend on adherence to study protocol. Short message service (also known as text message) reminders have been shown to improve clinical trial adherence in the United States and elsewhere. However, due to systematic differences in mobile data plans, languages, and technology, these systems are not easily translated to international settings. METHODS: To gauge technical capabilities for international projects, we developed SMSMessenger, an automated Android application that uses a US server to send medication reminders to participants in a clinical trial in St. Petersburg, Russia (Zinc for HIV disease among alcohol users-a randomized controlled trial in the Russia Alcohol Research Collaboration on HIV/AIDS cohort). The application is downloaded once onto an Android study phone. When it is time for the text message reminders to be sent, study personnel access the application on a local phone, which in turn accesses the existing clinical trial database hosted on a US web server. The application retrieves a list of participants with the following information: phone number, whether a message should be received at that time, and the appropriate text of the message. The application is capable of storing multiple outgoing messages. With a few clicks, text messages are sent to study participants who can reply directly to the message. Study staff can check the local phone for incoming messages. The SMSMessenger application uses an existing clinical trial database and is able to receive real-time updates. All communications between the application and server are encrypted, and phone numbers are stored in a secure database behind a firewall. No sensitive data are stored on the phone, as outgoing messages are sent through the application and not by messaging features on the phone itself. Messages are sent simultaneously to study participants, which reduces the burden on local study staff. Costs and setup are minimal. The only local requirements are an Android phone and data plan. CONCLUSION: The SMSMessenger technology could be modified to be applied anywhere in the world, in any language, script, or alphabet, and for many different purposes. The novel application of this existing low-cost technology can improve the usefulness of text messaging in advancing the goals of international clinical trials.


Assuntos
Infecções por HIV/tratamento farmacológico , Internacionalidade , Adesão à Medicação/estatística & dados numéricos , Aplicativos Móveis , Sistemas de Alerta , Envio de Mensagens de Texto , Alcoolismo/epidemiologia , Telefone Celular , Segurança Computacional , Confidencialidade , Custos e Análise de Custo , Método Duplo-Cego , Infecções por HIV/epidemiologia , Humanos , Projetos de Pesquisa , Federação Russa , Estados Unidos , Zinco/administração & dosagem
9.
MMWR Morb Mortal Wkly Rep ; 66(27): 718-722, 2017 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-28704346

RESUMO

Amyotrophic lateral sclerosis (ALS) and Parkinson's disease, both progressive neurodegenerative diseases, affect >1 million Americans (1,2). Consistently reported risk factors for ALS include increasing age, male sex, and cigarette smoking (1); risk factors for Parkinson's disease include increasing age, male sex, and pesticide exposure, whereas cigarette smoking and caffeine consumption are inversely associated (2). Relative to cancer or respiratory diseases, the role of occupation in neurologic diseases is much less studied and less well understood (3). CDC evaluated associations between usual occupation and ALS and Parkinson's disease mortality using data from CDC's National Institute for Occupational Safety and Health (NIOSH) National Occupational Mortality Surveillance (NOMS), a population-based surveillance system that includes approximately 12.1 million deaths from 30 U.S. states.* Associations were estimated using proportionate mortality ratios (PMRs), standardizing indirectly by age, sex, race, and calendar year to the standard population of all NOMS deaths with occupation information. Occupations associated with higher socioeconomic status (SES) had elevated ALS and Parkinson's disease mortality. The shifts in the U.S. workforce toward older ages and higher SES occupations† highlight the importance of understanding this finding, which will require studies with designs that provide evidence for causality, detailed exposure assessment, and adjustment for additional potential confounders.


Assuntos
Esclerose Lateral Amiotrófica/mortalidade , Disparidades nos Níveis de Saúde , Ocupações/estatística & dados numéricos , Doença de Parkinson/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Classe Social , Estados Unidos/epidemiologia , Adulto Jovem
10.
J Prim Prev ; 35(2): 75-84, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24421075

RESUMO

Alcohol use among first-year university students continues to be a central health concern. Efforts to address drinking in this population have increasingly relied on web-based interventions, which have the capacity to reach large numbers of students through a convenient and highly utilized medium. Despite evidence for the utility of this approach for reducing hazardous drinking, recent studies that have examined the effectiveness of this approach as a universal prevention strategy in campus-wide studies have produced mixed results. We sought to test the effectiveness of a web-based alcohol intervention as a universal prevention strategy for first-year students. An e-mail invitation linked to a brief, web-based survey on health behaviors was sent to all first-year students during the fall semester. Those who completed the baseline assessment were randomized to receive either a feedback-based alcohol intervention (intervention condition) or feedback about other health-related behaviors such as sleep and nutrition (control condition). A second web-based survey was used to collect follow-up drinking data 5 months later. The number of heavy drinking episodes in the previous month and alcohol-related consequences in the previous 3 months served as the primary dependent variables. Negative binomial regression analyses did not indicate a significant effect of the intervention at follow-up on either heavy drinking episodes or alcohol-related consequences. Analyses of additional drinking outcomes among the subsample of students who reported that they did not drink at baseline showed that those who received the alcohol intervention were subsequently less likely to drink alcohol. These results suggest that web-based alcohol interventions may be a potentially useful method of maintaining abstinence among underage, non-drinking students. Overall, however, results indicate that an e-mail-linked, campus-wide, web-intervention approach to address alcohol use among first-year students may have limited effectiveness as an approach to minimize hazardous drinking over the course of the year.


Assuntos
Consumo de Bebidas Alcoólicas/prevenção & controle , Correio Eletrônico , Retroalimentação Psicológica , Comportamentos Relacionados com a Saúde , Internet , Estudantes/psicologia , Estudos de Coortes , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Assunção de Riscos , Adulto Jovem
11.
PLoS One ; 8(2): e55135, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23383308

RESUMO

BACKGROUND: Therapeutic antibodies targeting the IGF1R have shown diverse efficacy and safety signals in oncology clinical trials. The success of these agents as future human therapeutics depends on understanding the specific mechanisms by which these antibodies target IGF1R signaling. METHODOLOGY/PRINCIPAL FINDINGS: A panel of well-characterized assays was used to investigate the mechanisms by which ganitumab, a fully human anti-IGF1R antibody undergoing clinical testing, inhibits IGF1R activity. Epitope mapping using IGF1R subdomains localized the ganitumab binding site to the L2 domain. Binding of ganitumab inhibited the high-affinity interaction of IGF-1 and IGF-2 required to activate IGF1R in cells engineered for IGF1R hypersensitivity and in human cancer cell lines, resulting in complete blockade of ligand-induced cellular proliferation. Inhibition of IGF1R activity by ganitumab did not depend on endosomal sequestration, since efficient ligand blockade was obtained without evidence of receptor internalization and degradation. Clinically relevant concentrations of ganitumab also inhibited the activation of hybrid receptors by IGF-1 and IGF-2. Ganitumab was not an agonist of homodimeric IGF1R or hybrid receptors in MCF-7 and COLO 205 cells, but low-level IGF1R activation was detected in cells engineered for IGF1R hypersensitivity. This activation seems biologically irrelevant since ganitumab completely inhibited ligand-driven proliferation. The in vivo efficacy profile of ganitumab was equivalent or better than CR and FnIII-1 domain-specific antibodies, alone or in combination with irinotecan. CR domain-specific antibodies only blocked IGF-1 binding to IGF1R but were more potent than ganitumab at inducing homodimer and hybrid receptor downregulation in vitro, however this difference was less obvious in vivo. No inhibition of hybrid receptors was observed with the FnIII-1 domain antibodies, which were relatively strong homodimer and hybrid agonists. CONCLUSIONS/SIGNIFICANCE: The safety and efficacy profile of ganitumab and other anti-IGF1R antibodies may be explained by the distinct molecular mechanisms by which they inhibit receptor signaling.


Assuntos
Anticorpos Monoclonais/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Análise de Variância , Animais , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais Humanizados , Afinidade de Anticorpos , Sítios de Ligação/genética , Proliferação de Células , Mapeamento de Epitopos , Feminino , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Células MCF-7 , Camundongos , Camundongos Nus , Fosforilação , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo
12.
Integr Cancer Ther ; 12(3): 248-56, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23027830

RESUMO

Previous studies have shown that soybean fermentation products can act as cancer chemoprevention or therapeutic agents. In this study, the anticancer activities of a fermentation product of soybean, black bean, and green bean mixture (BN999) were investigated. We found that BN999 inhibited the growth of human breast cancer AU565 cells and prostate adenocarcinoma PC-3 cells but not that of normal human cells. BN999 induced apoptosis in various human cancer cells but not in normal human cells. BN999 treatment of AU565 cancer cells resulted in activation of calpain and caspase-8, -9, and -3, suggesting that BN999 induces apoptosis via receptor-, mitochondria-, and endoplasmic reticulum-mediated pathways. Finally, we showed that BN999 inhibited the growth of mouse CT-26 colon cancer xenografts in syngenic BALB/c mice without causing obvious side effects. Together, these data suggest that BN999 has potential to be used as a cancer chemoprevention or therapeutic agent.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Fabaceae/química , Glycine max/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Animais , Caspases/metabolismo , Linhagem Celular Tumoral , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Fabaceae/metabolismo , Fermentação , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Glycine max/metabolismo
13.
Int Arch Allergy Immunol ; 156(2): 128-36, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21576983

RESUMO

BACKGROUND: Beneficial effects of probiotics have been reported for patients with allergic diseases and intestinal disorders. There is increasing interest in studying the role of different strains or combined probiotic administration on immunoregulation. In this study, we investigated whether probiotics modulate the immune response through regulating T cell proliferation and differentiation. METHODS: We examined the effect of probiotic I (a combination of Lactobacillus acidophilus and Bifidobacterium bifidus) and probiotic II (a combination of L. acidophilus and B. infantis) on cell survival and proliferation, the progression of the cell cycle, and the production of Th1/Th2 cytokines by mitogen-stimulated murine spleen cells and human peripheral blood mononuclear cells (PBMCs). RESULTS: Our experimental results showed that high concentrations (≥ 1 × 10(6) CFU/ml) of probiotic I or II inhibited mitogen-induced cell proliferation and arrested the cell cycle at the G0/G1 stage in both mitogen-stimulated spleen cells and PBMCs. In the results of low concentrations (<1 × 10(6) CFU/ml), probiotic I or II enhanced the production of IFN-γ but inhibited the production of IL-4. Our results indicated that high concentrations of probiotic I or II treatment could attenuate mitogen-induced overactive immune responses. On the other hand, low concentrations of probiotic I or II treatment could promote a shift in the Th1/Th2 balance toward Th1-skewed immunity. CONCLUSION: Dose selection is an important issue for probiotic studies. Our results indicated that probiotics have beneficial effects on regulating T cell-mediated immune responses by attenuating mitogen-induced overactive immune responses and promoting Th1 immune responses.


Assuntos
Bifidobacterium/imunologia , Fatores Imunológicos/farmacologia , Lactobacillus/imunologia , Probióticos/farmacologia , Linfócitos T/imunologia , Linfócitos T/microbiologia , Animais , Ciclo Celular/imunologia , Sobrevivência Celular/imunologia , Citometria de Fluxo , Humanos , Interferon gama/imunologia , Interleucina-4/imunologia , Leucócitos Mononucleares , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C
14.
Bioorg Med Chem Lett ; 21(8): 2394-9, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21414779

RESUMO

The insulin-like growth factor-1 receptor (IGF-1R) plays an important role in the regulation of cell growth and differentiation, and in protection from apoptosis. IGF-1R has been shown to be an appealing target for the treatment of human cancer. Herein, we report the synthesis, structure-activity relationships (SAR), X-ray cocrystal structure and in vivo tumor study results for a series of 2,4-bis-arylamino-1,3-pyrimidines.


Assuntos
Inibidores de Proteínas Quinases/química , Pirimidinas/química , Quinolinas/síntese química , Receptor IGF Tipo 1/antagonistas & inibidores , Animais , Sítios de Ligação , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos , Humanos , Camundongos , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacocinética , Pirimidinas/síntese química , Pirimidinas/farmacocinética , Quinolinas/química , Quinolinas/farmacocinética , Receptor IGF Tipo 1/metabolismo , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Am J Kidney Dis ; 56(6): 1108-16, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20951487

RESUMO

BACKGROUND: The ACHIEVE (Optimizing the Treatment of Secondary Hyperparathyroidism: A Comparison of Sensipar and Low Dose Vitamin D vs Escalating Doses of Vitamin D Alone) trial evaluated the efficacy of treatment with cinacalcet plus low-dose activated vitamin D analogues (Cinacalcet-D) compared with vitamin D analogues alone (Flex-D) in attaining KDOQI (Kidney Disease Outcomes Quality Initiative) targets for secondary hyperparathyroidism (SHPT). The economic implications of these treatment regimens have not been explored. STUDY DESIGN: Economic analysis of SHPT treatment in hemodialysis patients. SETTING & POPULATION: This analysis used data from the ACHIEVE trial, in which patients received either Cinacalcet-D or Flex-D. MODEL, PERSPECTIVE, & TIME FRAME: We assessed the relative cost-effectiveness of these regimens in treating SHPT during the 27-week ACHIEVE trial, using a US payer perspective, with medication costs valued in 2006 US dollars. INTERVENTION & OUTCOMES: Relative cost-effectiveness was assessed using cost-minimization analysis or incremental cost-effectiveness ratios. Effectiveness was measured using biochemical markers. RESULTS: Mean medication costs per patient were $5,852 and $4,332 for the Cinacalcet-D and Flex-D treatment arms, respectively. There were no significant differences for the primary end point (parathyroid hormone level of 150-300 pg/mL and calcium-phosphorus product < 55 mg²/dL²) and several of the secondary end points, rendering Cinacalcet-D more costly than Flex-D. For secondary end points, for which Cinacalcet-D was more effective, incremental cost-effectiveness ratios ranged from $2,957 (calcium < 9.5 mg/dL) to $22,028 (all KDOQI targets) per patient reaching target. Switching to generic calcitriol would have increased the cost difference between treatment arms ($2,079), whereas switching sevelamer to lanthanum decreased the difference ($1,426). LIMITATIONS: Costs and outcomes were derived from a short-term randomized controlled trial and were protocol driven. Clinical outcomes, such as mortality, were not available. Long-term economic conclusions cannot be drawn from these data. CONCLUSIONS: Cinacalcet combined with vitamin D analogues was no more effective than vitamin D analogues in achieving the primary ACHIEVE end point and incurred greater costs. This conclusion was not tempered substantially by the cost of vitamin D analogues or oral phosphate binders. Whether the additional costs of cinacalcet are warranted will require longer term models to determine whether changes in serum levels of mineral metabolic markers translate into lower morbidity, mortality, and downstream costs.


Assuntos
Hiperparatireoidismo/tratamento farmacológico , Falência Renal Crônica/terapia , Naftalenos/economia , Naftalenos/uso terapêutico , Diálise Renal , Vitamina D/economia , Vitamina D/uso terapêutico , Adulto , Idoso , Cálcio/sangue , Cinacalcete , Análise Custo-Benefício , Técnicas de Apoio para a Decisão , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Humanos , Hiperparatireoidismo/sangue , Hiperparatireoidismo/etiologia , Falência Renal Crônica/sangue , Falência Renal Crônica/complicações , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Fósforo/sangue , Anos de Vida Ajustados por Qualidade de Vida , Resultado do Tratamento , Estados Unidos , Vitamina D/análogos & derivados
16.
J Clin Virol ; 49(4): 290-5, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20934910

RESUMO

BACKGROUND: Polymyositis (PM) and dermatomyositis (DM) are associated with high risk of nasopharyngeal carcinoma (NPC) in Asian countries. Epstein-Barr virus (EBV) might induce autoimmunity and malignancies in susceptible individuals. OBJECTIVES: To investigate the association of EBV with PM/DM and NPC in PM/DM patients. STUDY DESIGN: Serum levels of anti-EBV viral capsid antigens (VCA) and anti-EBV-coded nuclear antigens-1 (EBNA-1) antibodies were measured by ELISA, and EBV DNA loads were determined using real-time PCR for 98 PM/DM patients, 94 systemic lupus erythematosus (SLE) patients and 370 healthy controls (HC). Anti-transfer-RNA synthetase antibodies (ASA) were determined by radioimmunoprecipitation for PM/DM patients. RESULTS: Thirteen (13.3%) of PM/DM patients vs. none of SLE patients had detectable NPC. ASA were detectable in 31.7% of PM/DM without malignancy, while lack of ASA in any PM/DM patient with NPC. IgA anti-EBNA-1 were detectable in 30.6% of PM/DM patients and 31.9% of SLE patients, but only in 4.1% of HC (odds ratio [OR] 10.44 and 11.12 respectively, both p<0.001). Significantly higher positivity for IgA anti-EBNA-1 were observed in PM/DM with NPC than in those without malignancy (OR 44.7, p<0.01). Significantly higher positivity for EBV genome were observed in PM/DM with NPC than in those without malignancy (OR 43.9, p<0.01), in SLE patients (OR 13.2, p<0.05) and in HC (OR 99.4, p<0.001). EBV DNA loads were significantly higher in PM/DM with NPC compared with those without malignancy and HC. CONCLUSIONS: Our results showed a positive association of EBV with PM/DM and NPC. PM/DM patients who have IgA anti-EBNA-1 or increased EBV DNA loads should be highly suspected to have occult NPC.


Assuntos
Dermatomiosite/virologia , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/isolamento & purificação , Síndromes Paraneoplásicas/virologia , Adulto , Idoso , Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Proteínas do Capsídeo/sangue , Carcinoma , DNA Viral/sangue , Ensaio de Imunoadsorção Enzimática , Antígenos Nucleares do Vírus Epstein-Barr/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/virologia , Carga Viral
17.
Cell ; 142(4): 531-43, 2010 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-20723755

RESUMO

Muscle wasting and cachexia have long been postulated to be key determinants of cancer-related death, but there has been no direct experimental evidence to substantiate this hypothesis. Here, we show that in several cancer cachexia models, pharmacological blockade of ActRIIB pathway not only prevents further muscle wasting but also completely reverses prior loss of skeletal muscle and cancer-induced cardiac atrophy. This treatment dramatically prolongs survival, even of animals in which tumor growth is not inhibited and fat loss and production of proinflammatory cytokines are not reduced. ActRIIB pathway blockade abolished the activation of the ubiquitin-proteasome system and the induction of atrophy-specific ubiquitin ligases in muscles and also markedly stimulated muscle stem cell growth. These findings establish a crucial link between activation of the ActRIIB pathway and the development of cancer cachexia. Thus ActRIIB antagonism is a promising new approach for treating cancer cachexia, whose inhibition per se prolongs survival.


Assuntos
Receptores de Activinas Tipo II/antagonistas & inibidores , Caquexia/tratamento farmacológico , Atrofia Muscular/tratamento farmacológico , Miocárdio/patologia , Neoplasias/complicações , Receptores de Activinas Tipo II/genética , Ativinas/metabolismo , Animais , Anorexia/tratamento farmacológico , Anorexia/etiologia , Atrofia/tratamento farmacológico , Atrofia/etiologia , Caquexia/etiologia , Feminino , Humanos , Inibinas/genética , Inibinas/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Musculares/metabolismo , Músculo Esquelético/patologia , Atrofia Muscular/etiologia , Mioblastos/patologia , Transplante de Neoplasias , Neoplasias/mortalidade , Transdução de Sinais , Transplante Heterólogo , Fator de Necrose Tumoral alfa/metabolismo
18.
Oncologist ; 15(3): 308-16, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20189976

RESUMO

BACKGROUND: Patient-reported outcomes (PROs) are essential for evaluating treatment effects on health-related quality of life and symptoms from the patient's perspective. This study sought to evaluate the psychometric properties of the nine-item Functional Assessment of Cancer Therapy/National Comprehensive Cancer Network Colorectal Cancer Symptom Index (FCSI-9) in a metastatic colorectal cancer (mCRC) population. METHODS: The FCSI-9 and EQ-5D were administered every 2-4 weeks to mCRC subjects in a phase III clinical trial. Three hundred ninety-one mCRC subjects completed the questionnaires at baseline and at least one follow-up assessment. Internal consistency reliability, test-retest reliability, construct validity, known groups validity, responsiveness, and the minimum important difference (MID) of the FCSI-9 were evaluated. RESULTS: The internal consistency and test-retest reliability of the FCSI-9 were acceptable (0.81 and 0.76, respectively). Construct validity was supported based on moderate correlations with the EQ-5D. Known groups validity was evaluated by examining the FCSI-9 scores of subjects categorized by their Eastern Cooperative Oncology Group performance status (PS) score. Subjects with better PS scores reported significantly higher FCSI-9 scores than those with lower PS scores at both baseline and week 8. Responsiveness, as measured by Guyatt's statistic, was 0.77 from baseline to week 8 and 0.60 from week 4 to week 12. Considering all data together, the MID of the FCSI-9 is estimated to be in the range of 1.5-3.0 points. CONCLUSION: Results provide preliminary evidence of the reliability, validity, and responsiveness of the FCSI-9.


Assuntos
Neoplasias Colorretais/psicologia , Avaliação de Resultados em Cuidados de Saúde/métodos , Psicometria/métodos , Idoso , Anticorpos Monoclonais/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Feminino , Humanos , Masculino , Cuidados Paliativos , Panitumumabe , Participação do Paciente , Satisfação do Paciente , Qualidade de Vida , Inquéritos e Questionários , Resultado do Tratamento
19.
Vaccine ; 27(47): 6613-8, 2009 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-19698812

RESUMO

The first universal hepatitis B vaccination program for newborns in the world was launched in Taiwan in July 1984. Most studies on the effectiveness of hepatitis B vaccination focused on the seroprevalence of HBs Ag among children under 14 years old. Only few studies focused on the seropositivity of anti-HBs among adolescents aged 15-18 years old. The present study aimed to evaluate the impact of the nationwide hepatitis B vaccination program on the immunity to HBV infection and the necessity of boost among adolescents. In this study including eight annual seroprevalence surveys from 2000 to 2007, 2342 college entrants (1589 15-year-olds in group I and 753 18-year-olds in group II) and 1851 university freshmen (18-year-olds in group III) participated. Subjects identified anti-HBs, HBs Ag and anti-HBc negative were given boost three doses of HBV vaccine. The HBs Ag seroprevalence was 11.6%, 3.5% and 1.0% for participants who were born before 1984, 1984-1986 and after 1986. The anti-HBs-seropositive rates were significantly higher in group II (83.1%) than in group I (53.0%) and group III (53.5%). All 572 participants who were seronegative for anti-HBs, HBs Ag and anti-HBc became anti-HBs-seropositive after catch-up vaccination. It is concluded that the anti-HBs-seropositive rate decreased to 50% in 15 years after vaccination, and boost vaccination was 100% effective. The necessity and age for boost among anti-HBs negative adolescents and the timing of the first immunization should be further evaluated.


Assuntos
Vacinas contra Hepatite B/administração & dosagem , Hepatite B/prevenção & controle , Imunização Secundária , Adolescente , Estudos Transversais , Feminino , Hepatite B/epidemiologia , Hepatite B/imunologia , Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Humanos , Programas de Imunização , Masculino , Estudos Soroepidemiológicos , Estudantes , Taiwan/epidemiologia
20.
J Clin Endocrinol Metab ; 94(8): 2766-72, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19470620

RESUMO

CONTEXT: Patients with persistent primary hyperparathyroidism (PHPT) after parathyroidectomy or with contraindications to parathyroidectomy often require chronic treatment for hypercalcemia. OBJECTIVE: The objective of the study was to assess the ability of the calcimimetic, cinacalcet, to reduce serum calcium in patients with intractable PHPT. DESIGN: This was an open-label, single-arm study comprising a titration phase of variable duration (2-16 wk) and a maintenance phase of up to 136 wk. SETTING: The study was conducted at 23 centers in Europe, the United States, and Canada. PATIENTS: The study included 17 patients with intractable PHPT and serum calcium greater than 12.5 mg/dl (3.1 mmol/liter). INTERVENTION: During the titration phase, cinacalcet dosages were titrated every 2 wk (30 mg twice daily to 90 mg four times daily) for 16 wk until serum calcium was 10 mg/dl or less (2.5 mmol/liter). If serum calcium increased during the maintenance phase, additional increases in the cinacalcet dose were permitted. MAIN OUTCOME MEASURE: The primary end point was the proportion of patients experiencing a reduction in serum calcium of 1 mg/dl or greater (0.25 mmol/liter) at the end of the titration phase. RESULTS: Mean +/- sd baseline serum calcium was 12.7 +/- 0.8 mg/dl (3.2 +/- 0.2 mmol/liter). At the end of titration, a 1 mg/dl or greater reduction in serum calcium was achieved in 15 patients (88%). Fifteen patients (88%) experienced treatment-related adverse events, none of which were serious. The most common adverse events were nausea, vomiting, and paresthesias. CONCLUSIONS: In patients with intractable PHPT, cinacalcet reduces serum calcium, is generally well tolerated, and has the potential to fulfill an unmet medical need.


Assuntos
Cálcio/sangue , Hiperparatireoidismo Primário/tratamento farmacológico , Naftalenos/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Cinacalcete , Feminino , Nível de Saúde , Humanos , Hiperparatireoidismo Primário/sangue , Hiperparatireoidismo Primário/psicologia , Masculino , Pessoa de Meia-Idade , Naftalenos/efeitos adversos , Hormônio Paratireóideo/sangue , Qualidade de Vida
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