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1.
Physiol Rev ; 98(3): 1241-1334, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29717932

RESUMO

Hypoxia is one of the most common and severe challenges to the maintenance of homeostasis. Oxygen sensing is a property of all tissues, and the response to hypoxia is multidimensional involving complicated intracellular networks concerned with the transduction of hypoxia-induced responses. Of all the stresses to which the fetus and newborn infant are subjected, perhaps the most important and clinically relevant is that of hypoxia. Hypoxia during gestation impacts both the mother and fetal development through interactions with an individual's genetic traits acquired over multiple generations by natural selection and changes in gene expression patterns by altering the epigenetic code. Changes in the epigenome determine "genomic plasticity," i.e., the ability of genes to be differentially expressed according to environmental cues. The genomic plasticity defined by epigenomic mechanisms including DNA methylation, histone modifications, and noncoding RNAs during development is the mechanistic substrate for phenotypic programming that determines physiological response and risk for healthy or deleterious outcomes. This review explores the impact of gestational hypoxia on maternal health and fetal development, and epigenetic mechanisms of developmental plasticity with emphasis on the uteroplacental circulation, heart development, cerebral circulation, pulmonary development, and the hypothalamic-pituitary-adrenal axis and adipose tissue. The complex molecular and epigenetic interactions that may impact an individual's physiology and developmental programming of health and disease later in life are discussed.


Assuntos
Desenvolvimento Fetal , Hipóxia Fetal/metabolismo , Adaptação Fisiológica , Tecido Adiposo/embriologia , Animais , Epigênese Genética , Feminino , Coração Fetal/crescimento & desenvolvimento , Cardiopatias/etiologia , Humanos , Hipertensão Pulmonar/congênito , Sistema Hipotálamo-Hipofisário , Saúde Materna , Sistema Hipófise-Suprarrenal , Circulação Placentária , Gravidez
2.
Breast Cancer Res Treat ; 205(1): 201-210, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38310616

RESUMO

PURPOSE: In 2010, the US Food and Drug Administration approved eribulin for the treatment of metastatic breast cancer (MBC). Since then, the treatment landscape has evolved with many new therapy classes, a more recent one being the small molecule inhibitors of phosphoinositide 3 kinase (PI3K). We sought to characterize the treatment patterns and clinical outcomes of patients with MBC who received eribulin following prior treatment with a PI3K inhibitor. METHODS: A retrospective cohort study based on medical record review included MBC patients who initiated eribulin between March 2019 and September 2020 following prior treatment with a PI3K inhibitor was conducted. Patient demographics, treatment characteristics, and clinical outcomes were analyzed descriptively. Real-world progression-free survival (rwPFS) and overall survival (OS) were estimated from the initiation of eribulin therapy using Kaplan-Meier analyses. RESULTS: 82 eligible patients were included. Patients' median age at eribulin initiation was 62 years; 86.5% had hormone receptor-positive, human epidermal growth factor receptor 2-negative tumors. Eribulin was most often administered in the second or third line (82.9%) in the metastatic setting. Best overall response on eribulin was reported as complete or partial response in 72% of the patients. The median rwPFS was 18.9 months (95% confidence interval [CI], 12.4-not estimable); median OS was not reached. The estimated rwPFS and OS rates at 12 months were 63.3% (95% CI, 50.5-73.7) and 82.6% (95% CI, 72.4-89.3), respectively. CONCLUSION: Our real-world study suggests that eribulin may be a potential treatment option for MBC patients who fail a prior PI3K inhibitor.


Assuntos
Neoplasias da Mama , Furanos , Cetonas , Inibidores de Fosfoinositídeo-3 Quinase , Policetídeos de Poliéter , Humanos , Furanos/uso terapêutico , Cetonas/uso terapêutico , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/mortalidade , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Inibidores de Fosfoinositídeo-3 Quinase/uso terapêutico , Adulto , Metástase Neoplásica , Resultado do Tratamento , Idoso de 80 Anos ou mais
3.
Future Oncol ; : 1-11, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629593

RESUMO

Aim: To assess real-world clinical outcomes with standard therapies for advanced non-small-cell lung cancer (aNSCLC) with METexon14 skipping mutation (METex14). Methods: In an oncologists-led retrospective review of medical records, data were abstracted and analyzed for patients initiating first-line (1L) systemic therapy after 1 January 2017. Results: In total 287 aNSCLC patients with METex14, the real-world best overall response rate was 73.4% for capmatinib (n = 146), 68.8% for immunotherapy (IO) monotherapy (n = 48), 52.0% for chemotherapy (CT, n = 30), and 54.8% for IO + CT (n = 63). As compared with capmatinib, patients receiving IO (hazard ratio [HR]: 1.57; 95% CI: 0.77-3.20; p = 0.220), CT (HR: 2.41; 95% CI: 1.19-4.85; p = 0.014) and IO + CT (HR: 2.33; 95% CI: 1.35-4.04; p = 0.003) had higher rates of progression. Further, patients receiving CT (HR: 4.43; 95% CI: 1.54-12.75; p = 0.006) and IO + CT (HR: 3.53, 95% CI: 1.41-8.85; p = 0.007) had higher rates of mortality than patients receiving capmatinib. Conclusion: The study showed better clinical outcomes with capmatinib than other standard therapies in 1L setting for aNSCLC harboring METex14.


Real-world study that investigated the outcomes of different therapies used to treat non-small-cell lung cancer patients with mesenchymal-epithelial transition exon 14 skipping mutationWhat is this article about? A real-world study that investigated clinical outcomes in patients with diagnosis of advanced non-small-cell lung cancer (aNSCLC) with mesenchymal-epithelial transition exon 14 (METex14) skipping­a rare form of genetic mutation­who received treatment with one of the commonly used therapies for this disease: immunotherapy, chemotherapy, immunotherapy + chemotherapy combination and capmatinib, which is a highly selective inhibitor of MET tyrosine kinase protein involved in the growth of cancer cells.What were the results? The study showed that, in general, patients treated with capmatinib as the frontline therapy more frequently achieved a clinical response in the form of complete tumor resolution or tumor shrinkage, had a lower risk of disease worsening and lived longer than patients who were treated with immunotherapy, chemotherapy or immunotherapy + chemotherapy combination.What do the results of the study mean? This study suggests that capmatinib is effective in treating patients with aNSCLC with METex14 skipping who have not been treated with another anticancer therapy previously. It provides evidence to support the use of capmatinib in the frontline setting and may inform clinical decision-making in routine practice.

4.
Cancer ; 129(7): 1051-1063, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36760031

RESUMO

BACKGROUND: Evidence on overall survival (OS) with cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors is generally limited to data from clinical trials or a few observational studies with limited generalizability to Medicare population. The aim of this study was to determine OS benefits associated with CDK4/6 inhibitors in older Medicare patients with hormone receptor (HR)-positive and human epidermal growth factor receptor-2 overexpressing (HER2-) metastatic breast cancer (MBC). METHODS: In a retrospective cohort design, female patients aged ≥65 years with diagnosis of HR+/HER2- MBC from 2015 to 2017 who initiated first-line systemic therapy within 12 months of MBC diagnosis were selected from the Survey Epidemiology and End Results-Medicare database. The effect of treatment type (endocrine therapy [ET]+CDK4/6 inhibitor vs. ET alone) on OS was analyzed using Kaplan-Meier methods and multivariable Cox regression models. Adjusted hazard ratio (aHR) and 95% CIs were estimated. RESULTS: A total of 630 eligible patients were identified (169 patients treated with ET+CDK4/6 inhibitor and 461 patients treated with ET alone). In the Kaplan-Meier analysis, OS rate at 3 years after first-line treatment initiation was 73.0% for ET+CDK4/6 inhibitor versus 49.1% for ET alone (log-rank p < .0001). In Cox regression analysis, first-line ET+CDK4/6 inhibitor therapy was associated with 41% lower rate of mortality versus ET alone (aHR, 0.590; 95% CI, 0.423-0.823). CONCLUSIONS: The findings of this real-world study demonstrate significant OS benefit associated with ET+CDK4/6 inhibitor therapy over ET alone in an older Medicare population of patients with HR+/HER2- MBC, largely consistent with the evidence from clinical trials.


Assuntos
Neoplasias da Mama , Inibidores de Proteínas Quinases , Idoso , Feminino , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Estimativa de Kaplan-Meier , Medicare , Receptor ErbB-2/metabolismo , Pesquisa , Estudos Retrospectivos , Estados Unidos/epidemiologia , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico , Taxa de Sobrevida
5.
Breast Cancer Res Treat ; 198(1): 159-166, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36609900

RESUMO

PURPOSE: Delaying chemotherapy remains a vital goal in therapeutic management of HR+/HER2- metastatic breast cancer (MBC). However, recent reports continue to highlight substantially high chemotherapy utilization in earlier therapy lines. In this study, we explored the impact of cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor therapy class, introduced in 2015, on early chemotherapy utilization in an older population of patients with HR+/HER2- MBC in the United States (US). METHODS: Using an interrupted time series design, patients with a confirmed diagnosis of MBC aged ≥ 65 years initiating systemic therapy during 2010-2019 were selected from the SEER-Medicare database. The proportion of chemotherapy use was summarized quarterly based on the date of treatment initiation separately in the first, second, and third lines. Segmented regression models adjusted for autocorrelation over time were fitted to estimate trends before and after the availability of CDK4/6 inhibitors in the first quarter of 2015. RESULTS: Of the 3244 eligible women (median age at diagnosis: 74 years), all initiated first-line therapy; 47.9% (n = 1581) initiated second-line therapy, and 50.1% (n = 792) initiated third-line therapy. Overall utilization of chemotherapy (alone or in combination) during the study period was 15.7% for the first line, 19.6% for the second line, and 24.8% for the third line. Chemotherapy utilization in the period immediately after introduction of CDK4/6 inhibitor therapy decline by estimated 2.5% in the first line (P = 0.408), 15.5% in the second line (P = 0.005), and 16.3% in the third line (P = 0.003). CONCLUSIONS: This population-based study illustrates that chemotherapy utilization in earlier therapy lines for HR+/HER2- MBC declined steadily between 2010 and 2019. These declines were significantly accelerated by the introduction of CDK4/6 therapy class in 2015, notably in the second- and third-line settings.


Assuntos
Neoplasias da Mama , Idoso , Humanos , Feminino , Estados Unidos/epidemiologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/epidemiologia , Medicare , Quinase 4 Dependente de Ciclina , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bases de Dados Factuais , Inibidores de Proteínas Quinases , Receptor ErbB-2
6.
Stat Med ; 42(20): 3593-3615, 2023 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-37392149

RESUMO

To effectively mitigate the spread of communicable diseases, it is necessary to understand the interactions that enable disease transmission among individuals in a population; we refer to the set of these interactions as a contact network. The structure of the contact network can have profound effects on both the spread of infectious diseases and the effectiveness of control programs. Therefore, understanding the contact network permits more efficient use of resources. Measuring the structure of the network, however, is a challenging problem. We present a Bayesian approach to integrate multiple data sources associated with the transmission of infectious diseases to more precisely and accurately estimate important properties of the contact network. An important aspect of the approach is the use of the congruence class models for networks. We conduct simulation studies modeling pathogens resembling SARS-CoV-2 and HIV to assess the method; subsequently, we apply our approach to HIV data from the University of California San Diego Primary Infection Resource Consortium. Based on simulation studies, we demonstrate that the integration of epidemiological and viral genetic data with risk behavior survey data can lead to large decreases in mean squared error (MSE) in contact network estimates compared to estimates based strictly on risk behavior information. This decrease in MSE is present even in settings where the risk behavior surveys contain measurement error. Through these simulations, we also highlight certain settings where the approach does not improve MSE.


Assuntos
COVID-19 , Doenças Transmissíveis , Infecções por HIV , Humanos , Teorema de Bayes , Fonte de Informação , SARS-CoV-2 , COVID-19/epidemiologia , Doenças Transmissíveis/epidemiologia , Infecções por HIV/epidemiologia
7.
BMC Infect Dis ; 23(1): 656, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794364

RESUMO

BACKGROUND: Efforts to control the HIV epidemic can benefit from knowledge of the relationships between the characteristics of people who have transmitted HIV and those who became infected by them. Investigation of this relationship is facilitated by the use of HIV genetic linkage analyses, which allows inference about possible transmission events among people with HIV infection. Two persons with HIV (PWH) are considered linked if the genetic distance between their HIV sequences is less than a given threshold, which implies proximity in a transmission network. The tendency of pairs of nodes (in our case PWH) that share (or differ in) certain attributes to be linked is denoted homophily. Below, we describe a novel approach to modeling homophily with application to analyses of HIV viral genetic sequences from clinical series of participants followed in San Diego. Over the 22-year period of follow-up, increases in cluster size results from HIV transmissions to new people from those already in the cluster-either directly or through intermediaries. METHODS: Our analytical approach makes use of a logistic model to describe homophily with regard to demographic, clinical, and behavioral characteristics-that is we investigate whether similarities (or differences) between PWH in these characteristics are associated with their sequences being linked. To investigate the performance of our methods, we conducted on a simulation study for which data sets were generated in a way that reproduced the structure of the observed database. RESULTS: Our results demonstrated strong positive homophily associated with hispanic ethnicity, and strong negative homophily, with birth year difference. The second result implies that the larger the difference between the age of a newly-infected PWH and the average age for an available cluster, the lower the odds of a newly infected person joining that cluster. We did not observe homophily associated with prior diagnosis of sexually transmitted diseases. Our simulation studies demonstrated the validity of our approach for modeling homophily, by showing that the estimates it produced matched the specified values of the statistical network generating model. CONCLUSIONS: Our novel methods provide a simple and flexible statistical network-based approach for modeling the growth of viral (or other microbial) genetic clusters from linkage to new infections based on genetic distance.


Assuntos
Infecções por HIV , Infecções Sexualmente Transmissíveis , Humanos , Etnicidade , Hispânico ou Latino , Modelos Estatísticos
8.
Future Oncol ; 19(3): 217-228, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36749292

RESUMO

Aim: To assess real-world clinical outcomes in patients with non-small-cell lung cancer with MET exon 14 skipping mutation and brain metastases (BM) who received capmatinib, a recently approved MET inhibitor, in routine US clinical practice. Materials & methods: Patient data were collected using a retrospective medical record review, led by participating oncologists. Eligible patients initiated treatment with capmatinib in any line, after BM diagnosis, between May 2020 and June 2021. Data on real-world overall response rate (rwORR) and real-world progression-free survival (rwPFS) were descriptively analyzed. Results: 68 eligible patients were analyzed. In patients treated with first-line (1L) capmatinib (n = 55), the rwORR was 90.9% systemically and 87.3% intracranially; median systemic rwPFS was 14.1 months. Among radiation-naive patients on 1L capmatinib (n = 20), rwORR was 85.0%, both systemically and intracranially; median systemic rwPFS was 14.1 months. Conclusion: This study showed substantial systemic and intracranial effectiveness for capmatinib in real-world setting; findings were consistent for RT-naive patients.


Assuntos
Neoplasias Encefálicas , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Éxons , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Estudos Retrospectivos
9.
Int J Mol Sci ; 24(8)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37108645

RESUMO

Neovascularization is an essential process in organismal development and aging. With aging, from fetal to adult life, there is a significant reduction in neovascularization potential. However, the pathways which play a role in increased neovascularization potential during fetal life are unknown. Although several studies proposed the idea of vascular stem cells (VSCs), the identification and essential survival mechanism are still not clear. In the present study, we isolated fetal VSCs from the ovine carotid artery and identified the pathways involved in their survival. We tested the hypothesis that fetal vessels contain a population of VSCs, and that B-Raf kinase is required for their survival. We conducted viability, apoptotic, and cell cycle stage assays on fetal and adult carotid arteries and isolated cells. To determine molecular mechanisms, we conducted RNAseq, PCR, and western blot experiments to characterize them and identify pathways essential for their survival. Results: A stem cell-like population was isolated from fetal carotid arteries grown in serum-free media. The isolated fetal VSCs contained markers for endothelial, smooth muscle, and adventitial cells, and formed a de novo blood vessel ex vivo. A transcriptomic analysis that compared fetal and adult arteries identified pathway enrichment for several kinases, including B-Raf kinase in fetal arteries. Furthermore, we demonstrated that B-Raf- Signal Transducer and Activator of Transcription 3 (STAT3)-Bcl2 is critical for the survival of these cells. Fetal arteries, but not adult arteries, contain VSCs, and B-Raf-STAT3-Bcl2 plays an important role in their survival and proliferation.


Assuntos
Proteínas Proto-Oncogênicas B-raf , Proteínas Proto-Oncogênicas c-bcl-2 , Ovinos , Animais , Células-Tronco , Proliferação de Células , Apoptose
10.
Clin Trials ; 19(4): 363-374, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35894099

RESUMO

Network science methods can be useful in design, monitoring, and analysis of randomized trials for control of spread of infections. Their usefulness arises from the role of statistical network models in molecular epidemiology and in study design. Computational models, such as agent-based models that propagate disease on simulated contact networks, can be used to investigate the properties of different study designs and analysis plans. Particularly valuable is the use of these methods to assess how magnitude and detectability of intervention effects depend on both individual-level and network-level characteristics of the enrolled populations. Such investigation also provides an important approach to assessing consequences of study data being incomplete or measured with error. To address these goals, we consider two statistical network models: exponential random graph models and the more flexible congruence class models. We focus first on an historical use of these methods in design and monitoring of a cluster randomized trial in Botswana to evaluate the effect of combination HIV prevention modalities compared to standard of care on HIV incidence. We then present a framework for the design of a study of booster vaccine effects on infection with, and forward transmission of, SARS-CoV-2 variants. Motivation for the study is driven in part by guidance from the United Kingdom to base approval of booster vaccines with "strain changes" that target variants on results of neutralizing antibody tests and information about safety, but without requiring evidence of clinical efficacy. Using designs informed by our agent-based network models, we show it may be feasible to conduct a trial of novel SARS-CoV-2 vaccines in a single large campus to obtain useful information regarding vaccine efficacy against susceptibility and infectiousness. If needed, the sample size could be increased by extending the study to a small number of campuses. Novel network methods may be useful in developing pragmatic SARS-CoV-2 vaccine trials that can leverage existing infrastructure to reduce costs and hasten the development of results.


Assuntos
COVID-19 , Infecções por HIV , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/uso terapêutico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2 , Vacinação
11.
Cell Tissue Bank ; 23(1): 79-92, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33768473

RESUMO

Biological detergents like sodium deoxycholate, sodium dodecyl sulphate and Triton X-100 impairs the collagenous and non-collagenous proteins, glycosaminoglycans and growth factors. Further, certain chemical and enzymes are responsible for residual cytotoxicity in the decellularized extracellular matrix. The main focus of this study was to explore the decellularization property of soap nut pericarp extract (SPE) for development of decellularized tubular esophageal scaffold. For this 2.5, 5.0 and 10% concentrations of SPE were used for decellularization of caprine esophageal tissues. Histological analysis of hematoxylin and eosin and Masson's trichrome stained tissue samples confirmed decellularization with preservation of extracellular matrix microarchitecture. Scanning electron microscopic images of luminal surface of decellularized esophageal matrix showed randomly oriented collagen fibres with large interconnected pores and cells were absent. However, the external surface was more textured with fibrous structures and collagen fibres were well preserved. DAPI stained decellularized tissues revealed complete removal of nuclear components, verified by DNA content measurement and SDS-PAGE. The FTIR spectra of decellularized esophagus shows absorption peaks of amide A, B, I, II and III. Elastic modulus of the decellularized esophagus scaffolds increased (P > 0.05) as compared to native tissues. Histological and scanning electron microscopic evaluation of in vitro seeded scaffolds showed attachment and growth of primary chicken embryo fibroblasts over and within the decellularized scaffolds. It was concluded that 5% SPE is ideal for preparation of cytocompatible decellularized caprine esophageal scaffold with well-preserved extracellular matrix architecture and, may be used as an alternative to biological detergents and other chemicals.


Assuntos
Sapindus , Engenharia Tecidual , Animais , Embrião de Galinha , Esôfago , Matriz Extracelular , Frutas , Cabras , Extratos Vegetais , Engenharia Tecidual/métodos , Alicerces Teciduais/química
12.
Clin Infect Dis ; 73(9): 1735-1741, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33462589

RESUMO

Universities are faced with decisions on how to resume campus activities while mitigating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) risk. To provide guidance for these decisions, we developed an agent-based network model of SARS-CoV-2 transmission to assess the potential impact of strategies to reduce outbreaks. The model incorporates important features related to risk at the University of California San Diego. We found that structural interventions for housing (singles only) and instructional changes (from in-person to hybrid with class size caps) can substantially reduce the basic reproduction number, but masking and social distancing are required to reduce this to at or below 1. Within a risk mitigation scenario, increased frequency of asymptomatic testing from monthly to twice weekly has minimal impact on average outbreak size (1.1-1.9), but substantially reduces the maximum outbreak size and cumulative number of cases. We conclude that an interdependent approach incorporating risk mitigation, viral detection, and public health intervention is required to mitigate risk.


Assuntos
COVID-19 , Universidades , Número Básico de Reprodução , Surtos de Doenças/prevenção & controle , Humanos , SARS-CoV-2
13.
Stat Med ; 40(13): 3167-3180, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33811360

RESUMO

A Bayesian approach to conduct network model selection is presented for a general class of network models referred to as the congruence class models (CCMs). CCMs form a broad class that includes as special cases several common network models, such as the Erdos-Rényi-Gilbert model, stochastic block model, and many exponential random graph models. Due to the range of models that can be specified as CCMs, our proposed method is better able to select models consistent with generative mechanisms associated with observed networks than are current approaches. In addition, our approach allows for incorporation of prior information. We illustrate the use of this approach to select among several different proposed mechanisms for the structure of patient-sharing networks; such networks have been found to be associated with the cost and quality of medical care. We found evidence in support of heterogeneity in sociality but not selective mixing by provider type or degree.


Assuntos
Teorema de Bayes , Humanos
14.
Inflammopharmacology ; 29(4): 1061-1074, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34185201

RESUMO

The liver acts as a manufacturing unit for the production of fetuin-A, which is essential for various physiological characteristics. Scientific research has shown that a moderate upward push in fetuin-A serum levels is associated with a confirmed non-alcoholic fatty liver disease (NAFLD) diagnosis. Fetuin-A modulation is associated with a number of pathophysiological variables that cause liver problems, including insulin receptor signaling deficiencies, adipocyte dysfunction, hepatic inflammation, fibrosis, triacylglycerol production, macrophage invasion, and TLR4 activation. The focus of the present review is on the various molecular pathways, and genetic relevance of mRNA expression of fetuin-A which is correlated with progression of NAFLD. The other major area of exploration in the present review is based on the new targets for the modulation of fetuin-A, like calorie restriction and novel pharmacological agents, such as rosuvastatin, metformin, and pioglitazone which are successfully implicated in the management of various liver-related complications.


Assuntos
Fígado/metabolismo , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , alfa-2-Glicoproteína-HS/biossíntese , Adiponectina/antagonistas & inibidores , Adiponectina/biossíntese , Adiponectina/genética , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Restrição Calórica/métodos , Humanos , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/metabolismo , Resistência à Insulina/fisiologia , Fígado/efeitos dos fármacos , Metformina/farmacologia , Metformina/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/genética , alfa-2-Glicoproteína-HS/antagonistas & inibidores , alfa-2-Glicoproteína-HS/genética
16.
J Physiol ; 597(24): 5835-5858, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31665811

RESUMO

KEY POINTS: Previous studies in fetuses with intrauterine growth restriction (IUGR) have shown that adrenergic dysregulation was associated with low insulin concentrations and greater insulin sensitivity. Although whole-body glucose clearance is normal, 1-month-old lambs with IUGR at birth have higher rates of hindlimb glucose uptake, which may compensate for myocyte deficiencies in glucose oxidation. Impaired glucose-stimulated insulin secretion in IUGR lambs is due to lower intra-islet insulin availability and not from glucose sensing. We investigated adrenergic receptor (ADR) ß2 desensitization by administering oral ADRß modifiers for the first month after birth to activate ADRß2 and antagonize ADRß1/3. In IUGR lambs ADRß2 activation increased whole-body glucose utilization rates and insulin sensitivity but had no effect on isolated islet or myocyte deficiencies. IUGR establishes risk for developing diabetes. In IUGR lambs we identified disparities in key aspects of glucose-stimulated insulin secretion and insulin-stimulated glucose oxidation, providing new insights into potential mechanisms for this risk. ABSTRACT: Placental insufficiency causes intrauterine growth restriction (IUGR) and disturbances in glucose homeostasis with associated ß adrenergic receptor (ADRß) desensitization. Our objectives were to measure insulin-sensitive glucose metabolism in neonatal lambs with IUGR and to determine whether daily treatment with ADRß2 agonist and ADRß1/ß3 antagonists for 1 month normalizes their glucose metabolism. Growth, glucose-stimulated insulin secretion (GSIS) and glucose utilization rates (GURs) were measured in control lambs, IUGR lambs and IUGR lambs treated with adrenergic receptor modifiers: clenbuterol atenolol and SR59230A (IUGR-AR). In IUGR lambs, islet insulin content and GSIS were less than in controls; however, insulin sensitivity and whole-body GUR were not different from controls. Of importance, ADRß2 stimulation with ß1/ß3 inhibition increases both insulin sensitivity and whole-body glucose utilization in IUGR lambs. In IUGR and IUGR-AR lambs, hindlimb GURs were greater but fractional glucose oxidation rates and ex vivo skeletal muscle glucose oxidation rates were lower than controls. Glucose transporter 4 (GLUT4) was lower in IUGR and IUGR-AR skeletal muscle than in controls but GLUT1 was greater in IUGR-AR. ADRß2, insulin receptor, glycogen content and citrate synthase activity were similar among groups. In IUGR and IUGR-AR lambs heart rates were greater, which was independent of cardiac ADRß1 activation. We conclude that targeted ADRß2 stimulation improved whole-body insulin sensitivity but minimally affected defects in GSIS and skeletal muscle glucose oxidation. We show that risk factors for developing diabetes are independent of postnatal catch-up growth in IUGR lambs as early as 1 month of age and are inherent to the islets and myocytes.


Assuntos
Retardo do Crescimento Fetal/tratamento farmacológico , Resistência à Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Receptores Adrenérgicos beta 2/metabolismo , Agonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Agonistas de Receptores Adrenérgicos beta 2/farmacologia , Agonistas de Receptores Adrenérgicos beta 2/uso terapêutico , Antagonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Antagonistas de Receptores Adrenérgicos beta 2/farmacocinética , Antagonistas de Receptores Adrenérgicos beta 2/uso terapêutico , Animais , Atenolol/administração & dosagem , Atenolol/farmacologia , Atenolol/uso terapêutico , Células Cultivadas , Clembuterol/administração & dosagem , Clembuterol/farmacologia , Clembuterol/uso terapêutico , Feminino , Retardo do Crescimento Fetal/metabolismo , Glucose/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Músculo Esquelético/metabolismo , Ovinos
17.
Stat Med ; 37(2): 218-235, 2018 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-28745004

RESUMO

Analysis of sexual history data intended to describe sexual networks presents many challenges arising from the fact that most surveys collect information on only a very small fraction of the population of interest. In addition, partners are rarely identified and responses are subject to reporting biases. Typically, each network statistic of interest, such as mean number of sexual partners for men or women, is estimated independently of other network statistics. There is, however, a complex relationship among networks statistics; and knowledge of these relationships can aid in addressing concerns mentioned earlier. We develop a novel method that constrains a posterior predictive distribution of a collection of network statistics in order to leverage the relationships among network statistics in making inference about network properties of interest. The method ensures that inference on network properties is compatible with an actual network. Through extensive simulation studies, we also demonstrate that use of this method can improve estimates in settings where there is uncertainty that arises both from sampling and from systematic reporting bias compared with currently available approaches to estimation. To illustrate the method, we apply it to estimate network statistics using data from the Chicago Health and Social Life Survey. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Bioestatística/métodos , Comportamento Sexual , Parceiros Sexuais , Teorema de Bayes , Viés , Botsuana/epidemiologia , Chicago , Simulação por Computador , Escolaridade , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Humanos , Funções Verossimilhança , Masculino , Modelos Estatísticos , Inquéritos e Questionários
18.
Support Care Cancer ; 26(2): 539-548, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28921379

RESUMO

PURPOSE: The purpose of this study is to assess temporal trends in the use of granulocyte colony-stimulating factor (G-CSF) prophylaxis and risk of febrile neutropenia (FN) among older women receiving adjuvant chemotherapy for early-stage breast cancer. METHODS: Women aged ≥ 66 years with diagnosis of early-stage breast cancer who initiated selected adjuvant chemotherapy regimens were identified using the SEER-Medicare data from 2002 to 2012. Adjusted, calendar-year-specific proportions were estimated for use of G-CSF primary prophylaxis (PP) and secondary prophylaxis and FN risk in the first and the second/subsequent cycles during the first course of chemotherapy, using logistic regression models. calendar-year-specific mean probabilities were estimated with covariates set to modal values. RESULTS: Among 11,107 eligible patients (mean age 71.7 years), 74% received G-CSF in the first course of chemotherapy. Of all patients, 5819 (52%) received G-CSF PP, and among those not receiving G-CSF PP, only 5% received G-CSF secondary prophylaxis. The adjusted proportion using G-CSF PP increased from 6% in 2002 to 71% in 2012. During the same period, the adjusted risk of FN in the first cycle increased from 2% to 3%; the adjusted risk increased from 1.5% to 2.9% among those receiving G-CSF PP and from 2.3% to 3.5% among those not receiving G-CSF PP. CONCLUSION: The use of G-CSF PP increased substantially during the study period. Although channeling of higher-risk patients to treatment with G-CSF PP is expected, the adjusted risk of FN among patients treated with G-CSF PP tended to be lower than among those not receiving G-CSF PP.


Assuntos
Neoplasias da Mama/complicações , Quimioterapia Adjuvante/efeitos adversos , Neutropenia Febril/etiologia , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Idoso , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neutropenia Febril/patologia , Feminino , Humanos , Medicare , Risco , Fatores de Tempo , Estados Unidos
19.
J Assoc Physicians India ; 65(3): 106-107, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28462561

RESUMO

Marchiafava-Bignami Disease (MBD) is a progressive neurological disease, characterized by corpus callosal demyelination and necrosis and subsequent atrophy. It is usually seen in the context of alcoholism and malnutrition. Clinical diagnosis of this disease is quite challenging due to various presentations but a high degree of suspicion often leads to the correct diagnosis with help of neuroimaging. We report a case of MBD with a classical clinical course and typical radiological features. This case is highlighted in order to generate awareness regarding this uncommon but historic complication of chronic alcoholism.


Assuntos
Doença de Marchiafava-Bignami/diagnóstico por imagem , Adulto , Alcoolismo/complicações , Transtornos Neurológicos da Marcha/etiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Doença de Marchiafava-Bignami/etiologia
20.
Am J Physiol Endocrinol Metab ; 310(11): E1062-71, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27143557

RESUMO

Vitamin D status increases during healthy mammalian pregnancy, but the molecular determinants remain uncharacterized. The first objective of this study was to determine the effects of pregnancy, and the second objective was to examine the role of chronic hypoxia on vitamin D status and metabolism in an ovine model. We analyzed the plasma levels of cholecalciferol, 25-OH-D, and 1α,25-(OH)2D in nonpregnant ewes, near-term pregnant ewes, and their fetuses exposed to normoxia (low altitude) or hypoxia (high-altitude) for 100 days. Hypoxic sheep had increased circulating levels of 25-OH-D and 1α,25-(OH)2D compared with normoxic sheep. Hypoxia increases in 25-OH-D were associated with increased expression of renal 25-hydroxylases CYP2R1 and CYP2J. Pregnancy did not increase further the plasma levels of 25-OH-D, but it significantly increased those of the active metabolite, 1α,25-(OH)2D, in both normoxic and hypoxic ewes. Increased bioactivation of vitamin D correlated with increased expression of the vitamin D-activating enzyme CYP27b1 and decreased expression of the inactivating enzyme CYP24a1 in maternal kidneys and placentas. Hypoxia increased parathyroid hormone levels and further increased renal CYP27b1. Pregnancy and hypoxia decreased the expression of vitamin D receptor (VDR) in maternal kidney and lung, with opposite effects on placental VDR. We conclude that ovine pregnancy is a model of increased vitamin D status, and long-term hypoxia further improves vitamin D status due to pregnancy- and hypoxia-specific regulation of VDR and metabolic enzymes.


Assuntos
Doença da Altitude/sangue , Metabolismo Energético , Complicações na Gravidez/sangue , Receptores de Calcitriol/sangue , Vitamina D/sangue , Animais , Doença Crônica , Feminino , Estudos Longitudinais , Gravidez/sangue , Ovinos
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