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1.
J Natl Compr Canc Netw ; 22(1): 43-69, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38394770

RESUMO

Chronic myeloid leukemia (CML) is defined by the presence of Philadelphia chromosome resulting from a reciprocal translocation between chromosomes 9 and 22 [t9;22] that gives rise to a BCR::ABL1 fusion gene. CML occurs in 3 different phases (chronic, accelerated, and blast phase) and is usually diagnosed in the chronic phase in developed countries. Tyrosine kinase inhibitor (TKI) therapy is a highly effective treatment option for patients with chronic phase-CML. The primary goal of TKI therapy in patients with chronic phase-CML is to prevent disease progression to accelerated phase-CML or blast phase-CML. Discontinuation of TKI therapy with careful monitoring is feasible in selected patients. This manuscript discusses the recommendations outlined in the NCCN Guidelines for the diagnosis and management of patients with chronic phase-CML.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Leucemia Mieloide de Fase Crônica , Humanos , Crise Blástica/induzido quimicamente , Crise Blástica/tratamento farmacológico , Crise Blástica/genética , Inibidores de Proteínas Quinases/efeitos adversos , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Cromossomo Filadélfia , Leucemia Mieloide de Fase Crônica/tratamento farmacológico , Proteínas de Fusão bcr-abl/genética
2.
Int J Mol Sci ; 25(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38892202

RESUMO

Osteoarthritis (OA) is increasing worldwide, and previous work found that OA increases systemic cartilage oligomeric matrix protein (COMP), which has also been implicated in prostate cancer (PCa). As such, we sought to investigate whether OA augments PCa progression. Cellular proliferation and migration of RM1 murine PCa cells treated with interleukin (IL)-1α, COMP, IL-1α + COMP, or conditioned media from cartilage explants treated with IL-1α (representing OA media) and with inhibitors of COMP were assessed. A validated murine model was used for tumor growth and marker expression analysis. Both proliferation and migration were greater in PCa cells treated with OA media compared to controls (p < 0.001), which was not seen with direct application of the stimulants. Migration and proliferation were not negatively affected when OA media was mixed with downstream and COMP inhibitors compared to controls (p > 0.05 for all). Mice with OA developed tumors 100% of the time, whereas mice without OA only 83.4% (p = 0.478). Tumor weight correlated with OA severity (Pearson correlation = 0.813, p = 0.002). Moreover, tumors from mice with OA demonstrated increased Ki-67 expression compared to controls (mean 24.56% vs. 6.91%, p = 0.004) but no difference in CD31, PSMA, or COMP expression (p > 0.05). OA appears to promote prostate cancer in vitro and in vivo.


Assuntos
Proteína de Matriz Oligomérica de Cartilagem , Proliferação de Células , Osteoartrite , Neoplasias da Próstata , Masculino , Animais , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Camundongos , Proteína de Matriz Oligomérica de Cartilagem/metabolismo , Proteína de Matriz Oligomérica de Cartilagem/genética , Linhagem Celular Tumoral , Osteoartrite/metabolismo , Osteoartrite/patologia , Osteoartrite/etiologia , Movimento Celular/efeitos dos fármacos , Humanos , Modelos Animais de Doenças , Interleucina-1alfa/metabolismo
3.
Circulation ; 146(24): 1836-1854, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-35862223

RESUMO

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is a well-established treatment option for high- and intermediate-risk patients with severe symptomatic aortic valve stenosis. A majority of patients exhibit improvements in left ventricular ejection fraction (LVEF) after TAVR in response to TAVR-associated afterload reduction. However, a specific role for circulating microRNAs (miRNAs) in the improvement of cardiac function for patients after TAVR has not yet been investigated. Here, we profiled the differential expression of miRNAs in circulating extracellular vesicles (EVs) in patients after TAVR and, in particular, the novel role of circulating miR-122-5p in cardiomyocytes. METHODS: Circulating EV-associated miRNAs were investigated by use of an unbiased Taqman-based human miRNA array. Several EV miRNAs (miR-122-5p, miR-26a, miR-192, miR-483-5p, miR-720, miR-885-5p, and miR-1274) were significantly deregulated in patients with aortic valve stenosis at day 7 after TAVR compared with the preprocedural levels in patients without LVEF improvement. The higher levels of miR-122-5p were negatively correlated with LVEF improvement at both day 7 (r=-0.264 and P=0.015) and 6 months (r=-0.328 and P=0.0018) after TAVR. RESULTS: Using of patient-derived samples and a murine aortic valve stenosis model, we observed that the expression of miR-122-5p correlates negatively with cardiac function, which is associated with LVEF. Mice with graded wire injury-induced aortic valve stenosis demonstrated a higher level of miR-122-5p, which was related to cardiomyocyte dysfunction. Murine ex vivo experiments revealed that miR-122-5p is highly enriched in endothelial cells compared with cardiomyocytes. Coculture experiments, copy-number analysis, and fluorescence microscopy with Cy3-labeled miR-122-5p demonstrated that miR-122-5p can be shuttled through large EVs from endothelial cells into cardiomyocytes. Gain- and loss-of-function experiments suggested that EV-mediated shuttling of miR-122-5p increases the level of miR-122-5p in recipient cardiomyocytes. Mechanistically, mass spectrometry, miRNA pulldown, electrophoretic mobility shift assay, and RNA immunoprecipitation experiments confirmed that miR-122-5p interacts with the RNA-binding protein hnRNPU (heterogeneous nuclear ribonucleoprotein U) in a sequence-specific manner to encapsulate miR-122-5p into large EVs. On shuttling, miR-122-5p reduces the expression of the antiapoptotic gene BCL2 by binding to its 3' untranslated region to inhibit its translation, thereby decreasing the viability of target cardiomyocytes. CONCLUSIONS: Increased levels of circulating proapoptotic EV-incorporated miR-122-5p are associated with reduced LVEF after TAVR. EV shuttling of miR-122-5p regulates the viability and apoptosis of cardiomyocytes in a BCL2-dependent manner.


Assuntos
Estenose da Valva Aórtica , MicroRNA Circulante , Vesículas Extracelulares , MicroRNAs , Substituição da Valva Aórtica Transcateter , Humanos , Camundongos , Animais , Substituição da Valva Aórtica Transcateter/métodos , Função Ventricular Esquerda/fisiologia , Volume Sistólico/fisiologia , Células Endoteliais , Estenose da Valva Aórtica/cirurgia , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-bcl-2 , Valva Aórtica/cirurgia , Resultado do Tratamento
5.
Dig Dis Sci ; 68(7): 2946-2953, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37193930

RESUMO

BACKGROUND: As recommendations for non-invasive fibrosis risk assessment in nonalcoholic fatty liver disease (NAFLD) emerge, it is not known how often they are performed in primary care. AIMS: We investigated the completion of confirmatory fibrosis risk assessment in primary care patients with NAFLD and indeterminate-risk or greater Fibrosis-4 Index (FIB-4) and NAFLD Fibrosis Scores (NFS). METHODS: This retrospective cohort study of electronic health record data from a primary care clinic identified patients with diagnoses of NAFLD from 2012 through 2021. Patients with a diagnosis of a severe liver disease outcome during the study period were excluded. The most recent FIB-4 and NFS scores were calculated and categorized by advanced fibrosis risk. Charts were reviewed to identify the outcome of a confirmatory fibrosis risk assessment by liver elastography or liver biopsy for all patients with indeterminate-risk or higher FIB-4 (≥ 1.3) and NFS (≥ - 1.455) scores. RESULTS: The cohort included 604 patients diagnosed with NAFLD. Two-thirds of included patients (399) had a FIB-4 or NFS score greater than low-risk, 19% (113) had a high-risk FIB-4 (≥ 2.67) or NFS (≥ 0.676) score, and 7% (44) had high-risk FIB-4 and NFS values. Of these 399 patients with an indication for a confirmatory fibrosis test, 10% (41) underwent liver elastography (24) or liver biopsy (18) or both (1). CONCLUSIONS: Advanced fibrosis is a key indicator of future poor health outcomes in patients with NAFLD and a critical signal for referral to hepatology. Significant opportunities exist to improve confirmatory fibrosis risk assessment in patients with NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/patologia , Estudos Retrospectivos , Fígado/diagnóstico por imagem , Fígado/patologia , Medição de Risco , Atenção Primária à Saúde , Biópsia , Índice de Gravidade de Doença
6.
J Appl Clin Med Phys ; 24(7): e13953, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36877712

RESUMO

As cone-beam computed tomography (CBCT) has become the localization method for a majority of cases, the indications for diode-based confirmation of accurate patient set-up and treatment are now limited and must be balanced between proper resource allocation and optimizing efficiency without compromising safety. We undertook a de-implementation quality improvement project to discontinue routine diode use in non-intensity modulated radiotherapy (IMRT) cases in favor of tailored selection of scenarios where diodes may be useful. After analysis of safety reports from the last 5 years, literature review, and stakeholder discussions, our safety and quality (SAQ) committee introduced a recommendation to limit diode use to specific scenarios in which in vivo verification may add value to standard quality assurance (QA) processes. To assess changes in patterns of use, we reviewed diode use by clinical indication 4 months prior and after the implementation of the revised policy, which includes use of diodes for: 3D conformal photon fields set up without CBCT; total body irradiation (TBI); electron beams; cardiac devices within 10 cm of the treatment field; and unique scenarios on a case-by-case basis. We identified 4459 prescriptions and 1038 unique instances of diode use across five clinical sites from 5/2021 to 1/2022. After implementation of the revised policy, we observed an overall decrease in diode use from 32% to 13.2%, with a precipitous drop in 3D cases utilizing CBCT (from 23.2% to 4%), while maintaining diode utilization in the 5 selected scenarios including 100% of TBI and electron cases. By identifying specific indications for diode use and creating a user-friendly platform for case selection, we have successfully de-implemented routine diode use in favor of a selective process that identifies cases where the diode is important for patient safety. In doing so, we have streamlined patient care and decreased cost without compromising patient safety.


Assuntos
Dosimetria in Vivo , Radioterapia Conformacional , Humanos , Dosagem Radioterapêutica , Radioterapia Conformacional/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Elétrons , Radiometria/métodos
7.
Cancer Invest ; 39(10): 871-879, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34643126

RESUMO

Novel therapeutics are needed for patients with relapsed or refractory diffuse large B-cell lymphoma (R/R DLBCL). Everolimus is an mTOR pathway inhibitor with synergistic anti-tumor activity when combined with histone deacetylase inhibitors, such as panobinostat, in preclinical lymphoma models. In this Phase II study, we evaluated overall response rate to single and combination everolimus and panobinostat in R/R DLBCL. Fifteen patients were enrolled to single-agent and 18 to combination. One patient responded to everolimus, while none responded to panobinostat. Though 25% of patients responded to combination therapy, responses were not durable with significant toxicity. We demonstrated minimal single-agent activity and prohibitive toxicity with combination therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Everolimo/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Panobinostat/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Everolimo/administração & dosagem , Everolimo/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Panobinostat/administração & dosagem , Panobinostat/efeitos adversos , Estudos Prospectivos , Recidiva
8.
Am J Physiol Cell Physiol ; 318(1): C1-C28, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31483703

RESUMO

Although a majority of the mammalian genome is transcribed to RNA, mounting evidence indicates that only a minor proportion of these transcriptional products are actually translated into proteins. Since the discovery of the first non-coding RNA (ncRNA) in the 1980s, the field has gone on to recognize ncRNAs as important molecular regulators of RNA activity and protein function, knowledge of which has stimulated the expansion of a scientific field that quests to understand the role of ncRNAs in cellular physiology, tissue homeostasis, and human disease. Although our knowledge of these molecules has significantly improved over the years, we have limited understanding of their precise functions, protein interacting partners, and tissue-specific activities. Adding to this complexity, it remains unknown exactly how many ncRNAs there are in existence. The increased use of high-throughput transcriptomics techniques has rapidly expanded the list of ncRNAs, which now includes classical ncRNAs (e.g., ribosomal RNAs and transfer RNAs), microRNAs, and long ncRNAs. In addition, splicing by-products of protein-coding genes and ncRNAs, so-called circular RNAs, are now being investigated. Because there is substantial heterogeneity in the functions of ncRNAs, we have summarized the present state of knowledge regarding the functions of ncRNAs in heart, lungs, and skeletal muscle. This review highlights the pathophysiologic relevance of these ncRNAs in the context of human cardiovascular, pulmonary, and muscle diseases.


Assuntos
Doenças Cardiovasculares/genética , Pneumopatias/genética , Doenças Musculares/genética , RNA não Traduzido/genética , Animais , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/fisiopatologia , Regulação da Expressão Gênica , Marcadores Genéticos , Humanos , Pneumopatias/diagnóstico , Pneumopatias/metabolismo , Pneumopatias/fisiopatologia , Doenças Musculares/diagnóstico , Doenças Musculares/metabolismo , Doenças Musculares/fisiopatologia , Valor Preditivo dos Testes , RNA não Traduzido/metabolismo , Transdução de Sinais
9.
Cancer ; 126(19): 4362-4370, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32776520

RESUMO

BACKGROUND: The objective of this study was to determine whether standardized treatment of germ cell tumors (GCTs) could overcome sociodemographic factors limiting patient care. METHODS: The records of all patients undergoing primary treatment for GCTs at both a public safety net hospital and an academic tertiary care center in the same metropolitan area were analyzed. Both institutions were managed by the same group of physicians in the context of multidisciplinary cancer care. Patients were grouped by care center; clinicopathologic features and outcomes were analyzed. RESULTS: Between 2006 and 2018, 106 and 95 patients underwent initial treatment for GCTs at the safety net hospital and the tertiary care center, respectively. Safety net patients were younger (29 vs 33 years; P = .005) and were more likely to be Hispanic (79% vs 11%), to be uninsured (80% vs 12%; P < .001), to present via the emergency department (76% vs 8%; P < .001), and to have metastatic (stage II/III) disease (42% vs 26%; P = .025). In a multivariable analysis, an absence of lymphovascular invasion (odds ratio [OR], 0.30; P = .008) and an embryonal carcinoma component (OR, 0.36; P = .02) were associated with decreased use of adjuvant treatment for stage I patients; hospital setting was not (OR, 0.67; P = .55). For patients with stage II/III nonseminomatous GCTs, there was no difference in the performance of postchemotherapy retroperitoneal lymph node dissection between the safety net hospital and the tertiary care center (52% vs 64%; P = .53). No difference in recurrence rates was observed between the cohorts (5% vs 6%; P = .76). CONCLUSIONS: Sociodemographic factors are often associated with adverse clinical outcomes in the treatment of GCTs; they may be overcome with integrated, standardized management of testicular cancer.


Assuntos
Neoplasias Testiculares/epidemiologia , Adulto , Humanos , Masculino , Provedores de Redes de Segurança , Fatores Socioeconômicos
10.
Curr Opin Cardiol ; 35(3): 199-206, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32068613

RESUMO

PURPOSE OF REVIEW: Mounting evidence suggests that long noncoding RNAs (lncRNAs) are essential regulators of gene expression. Although few lncRNAs have been the subject of detailed molecular and functional characterization, it is believed that lncRNAs play an important role in tissue homeostasis and development. In fact, gene expression profiling studies reveal lncRNAs are developmentally regulated in a tissue-type and cell-type specific manner. Such findings have brought significant attention to their potential contribution to disease cause. The current review summarizes recent studies of lncRNAs in the heart. RECENT FINDINGS: lncRNA discovery has largely been driven by the implementation of next generation sequencing technologies. To date, such technologies have contributed to the identification of tens of thousands of distinct lncRNAs in humans -- accounting for a large majority of all RNA sequences transcribed across the human genome. Although the functions of these lncRNAs remain largely unknown, gain-of-function and loss-of-function studies (in vivo and in vitro) have uncovered a number of mechanisms by which lncRNAs regulate gene expression and protein function. Such mechanisms have been stratified according to three major functional categories: RNA sponges (RNA-mediated sequestration of free miRNAs; e.g. H19, MEG3, and MALAT1); transcription-modulating lncRNAs (RNA influences regulatory factor recruitment by binding to histone modifiers or transcription factors; e.g. CAIF, MANTIS, and NEAT1); and translation-modulating lncRNAs (RNA modifies protein function via directly interacting with a protein itself or binding partners; e.g. Airn, CCRR, and ZFAS1). SUMMARY: Recent studies strongly suggest that lncRNAs function via binding to macromolecules (e.g. genomic DNA, miRNAs, or proteins). Thus, lncRNAs constitute an additional mode by which cells regulate gene expression.


Assuntos
RNA Longo não Codificante/genética , Humanos
11.
Circ Res ; 122(10): 1347-1353, 2018 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-29483092

RESUMO

RATIONALE: Increasing evidence indicates the presence of lncRNAs in various cell types. Airn is an imprinting gene transcribed from the paternal chromosome. It is in antisense orientation to the imprinted, but maternally derived, Igf2r gene, on which Airn exerts its regulation in cis. Although Airn is highly expressed in the heart, functions aside from imprinting remain unknown. OBJECTIVE: Here, we studied the functions of Airn in the heart, especially cardiomyocytes. METHODS AND RESULTS: Silencing of Airn via siRNAs augmented cell death, vulnerability to cellular stress, and reduced cell migration. To find the cause of such phenotypes, the potential binding partners of Airn were identified via RNA pull-down followed by mass spectrometry, which indicated Igf2bp2 (insulin-like growth factor 2 mRNA-binding protein 2) and Rpa1 (replication protein A1) as potential binding partners. Further experiments showed that Airn binds to Igf2bp2 to control the translation of several genes. Moreover, silencing of Airn caused less binding of Igf2bp2 to other mRNAs and reduced translation of Igf2bp2 protein. CONCLUSIONS: Our study uncovers a new function of Airn and demonstrates that Airn is important for the physiology of cardiomyocytes.


Assuntos
Miócitos Cardíacos/metabolismo , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/biossíntese , Animais , Linhagem Celular , Movimento Celular , Regulação da Expressão Gênica , Camundongos , Infarto do Miocárdio/metabolismo , Especificidade de Órgãos , Ligação Proteica , Biossíntese de Proteínas , Interferência de RNA , Splicing de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Proteínas de Ligação a RNA/genética , Proteína de Replicação A/metabolismo
12.
J Natl Compr Canc Netw ; 18(10): 1385-1415, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33022644

RESUMO

Chronic myeloid leukemia (CML) is defined by the presence of Philadelphia chromosome (Ph) which results from a reciprocal translocation between chromosomes 9 and 22 [t(9;22] that gives rise to a BCR-ABL1 fusion gene. CML occurs in 3 different phases (chronic, accelerated, and blast phase) and is usually diagnosed in the chronic phase. Tyrosine kinase inhibitor therapy is a highly effective first-line treatment option for all patients with newly diagnosed chronic phase CML. This manuscript discusses the recommendations outlined in the NCCN Guidelines for the diagnosis and management of patients with chronic phase CML.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Leucemia Mieloide de Fase Crônica , Proteínas de Fusão bcr-abl/genética , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Oncologia , Cromossomo Filadélfia , Translocação Genética
13.
J Pers ; 88(4): 735-747, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31651040

RESUMO

OBJECTIVE: We employed self-determination theory (SDT) as a framework for examining longitudinal relations between adolescents' motivations to abstain from substances and their subsequent substance use. METHOD: Participants were 475 adolescents in the United States. The data came from annual surveys following adolescents from age 16 to 19. The measures included self-reports of controlled and autonomous motivations to abstain from substances, as well as substance use frequency. RESULTS: We used structural equation modeling to estimate autoregressive cross-lagged models of controlled and autonomous abstinence motivations predicting substance use a year later (with 3 years of data on abstinence motivations and 4 years of data on substance use). Autonomous motivation predicted decreases in substance use, while controlled motivation predicted increases. Follow-up analyses also revealed that relations between abstinence motivations and substance use increase in strength with greater time lags, and decreases in autonomous abstinence motivation partially mediate the link between controlled abstinence motivation and later substance use. CONCLUSIONS: This study demonstrated the usefulness of SDT in understanding motivations to abstain from substance use during adolescence. In line with this theoretical approach, autonomous motivations for abstinence were adaptive while controlled motivations for abstinence were maladaptive.


Assuntos
Comportamento do Adolescente/fisiologia , Motivação/fisiologia , Autonomia Pessoal , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Adolescente , Adulto , Feminino , Humanos , Estudos Longitudinais , Masculino , Teoria Psicológica , Adulto Jovem
14.
J Sports Sci ; 38(17): 2013-2020, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32516094

RESUMO

This study compared the effects of dictating load using individual (ILVP) or group (GLVP) load-velocity profiles on lower-body strength and power. Nineteen trained males (23.6 ± 3.7 years) completed a back squat one-repetition maximum (1-RM), load-velocity profiling (LVP), and countermovement (CMJ), static-squat (SSJ) and standing-broad (SBJ) jump tests before and after 6 weeks of resistance training. Participants were randomly assigned to an ILVP, or GLVP intervention with intra-session load dictated through real-time velocity monitoring and prediction of current relative performance using either the participant's LVP (ILVP) or a LVP based on all participant data (GLVP). Training resulted in significant increases in back squat 1-RM for the ILVP and GLVP group (p < 0.01; 9.7% and 7.2%, respectively), with no group-by-time interaction identified between training groups (p = 0.06). All jump performance significantly increased for the ILVP group (p < 0.01; CMJ: 6.6%; SSJ: 4.6%; SBJ: 6.7%), with only CMJ and SSJ improving for the GLVP group (p < 0.05; 4.3%). Despite no significant group-by-time interaction across all variables, the ILVP intervention induced a greater magnitude of adaptation when compared to a GLVP approach. Additionally, an individualised approach may lead to greater positive transfer to power-based movements, specifically vertical and horizontal jumps.


Assuntos
Força Muscular/fisiologia , Treinamento Resistido/métodos , Adaptação Fisiológica , Humanos , Masculino , Exercício Pliométrico , Fatores de Tempo , Levantamento de Peso/fisiologia , Adulto Jovem
15.
Appl Environ Microbiol ; 85(12)2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-30979840

RESUMO

Bacterial Halanaerobium strains become the dominant persisting microbial community member in produced fluids across geographically distinct hydraulically fractured shales. Halanaerobium is believed to be inadvertently introduced into this environment during the drilling and fracturing process and must therefore tolerate large changes in pressure, temperature, and salinity. Here, we used a Halanaerobium strain isolated from a natural gas well in the Utica Point Pleasant formation to investigate metabolic and physiological responses to growth under high-pressure subsurface conditions. Laboratory incubations confirmed the ability of Halanaerobium congolense strain WG8 to grow under pressures representative of deep shale formations (21 to 48 MPa). Under these conditions, broad metabolic and physiological shifts were identified, including higher abundances of proteins associated with the production of extracellular polymeric substances. Confocal laser scanning microscopy indicated that extracellular polymeric substance (EPS) production was associated with greater cell aggregation when biomass was cultured at high pressure. Changes in Halanaerobium central carbon metabolism under the same conditions were inferred from nuclear magnetic resonance (NMR) and gas chromatography measurements, revealing large per-cell increases in production of ethanol, acetate, and propanol and cessation of hydrogen production. These metabolic shifts were associated with carbon flux through 1,2-propanediol in response to slower fluxes of carbon through stage 3 of glycolysis. Together, these results reveal the potential for bioclogging and corrosion (via organic acid fermentation products) associated with persistent Halanaerobium growth in deep, hydraulically fractured shale ecosystems, and offer new insights into cellular mechanisms that enable these strains to dominate deep-shale microbiomes.IMPORTANCE The hydraulic fracturing of deep-shale formations for hydrocarbon recovery accounts for approximately 60% of U.S. natural gas production. Microbial activity associated with this process is generally considered deleterious due to issues associated with sulfide production, microbially induced corrosion, and bioclogging in the subsurface. Here we demonstrate that a representative Halanaerobium species, frequently the dominant microbial taxon in hydraulically fractured shales, responds to pressures characteristic of the deep subsurface by shifting its metabolism to generate more corrosive organic acids and produce more polymeric substances that cause "clumping" of biomass. While the potential for increased corrosion of steel infrastructure and clogging of pores and fractures in the subsurface may significantly impact hydrocarbon recovery, these data also offer new insights for microbial control in these ecosystems.


Assuntos
Matriz Extracelular de Substâncias Poliméricas/metabolismo , Firmicutes/metabolismo , Fraturamento Hidráulico , Pressão
16.
J Res Adolesc ; 29(2): 254-275, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31206875

RESUMO

This is a systematic review of 30 years (1988-2017) of empirical research on processes of religious/spiritual influence in adolescence. We followed a multi-step process that resulted in 241 studies organized according to eight research questions and the corresponding methods and analyses typically used to address them. We coded these studies based on the dimensions of religiosity/spirituality and the youth outcomes involved. In some cases (quantitative studies of mediation and moderation, as well as qualitative studies) we also coded a third process variable. Results of the coding process revealed a number of interesting patterns. First, religiosity/spirituality is generally adaptive for adolescents, protecting them from negative outcomes (e.g., risk behaviors and mental illness), and promoting positive youth development and flourishing. Nevertheless, in some contexts, religiosity/spirituality may be at least partially maladaptive. Second, there is some evidence, from experimental and longitudinal studies, that relations between religiosity/spirituality and adaptive outcomes are causal. Third, there are numerous complex and dynamic processes by which religiosity/spirituality relate to youth outcomes. In terms of mediation studies, the most salient mediating processes seem to involve religiosity/spirituality dimensions, peers, values/attitudes, and social control/norms. Fourth, religiosity/spirituality is multidimensional, involving various interwoven facets at the individual and ecological levels. Private or personal aspects of religiosity/spirituality (e.g., religious/spiritual importance) tend to be more salient predictors of outcomes than public aspects of religiosity/spirituality (e.g., religious worship service attendance). The results of this systematic review point to promising directions for future research. First, more research is needed studying a broader range of dimensions of religiosity/spirituality, processes of influence, and outcomes. In terms of religiosity/spirituality, much of the prior work has focused on overall religiosity/spirituality, and religious/spiritual behaviors (e.g., worship service attendance). In terms of outcomes, the emphasis has been on religiosity/spirituality protecting against maladaptive outcomes (e.g., substance use). Second, more research is needed examining the role of culture, and using more rigorous methods (e.g., experience sampling, experimental design, longitudinal design, or mixed methods). This systematic review provides a detailed analysis of what is known regarding processes of religious/spiritual influence in the lives of adolescents, and hopefully better positions researchers to move the field forward.


Assuntos
Psicologia do Adolescente , Espiritualidade , Adolescente , Humanos , Religião , Pesquisa , Fatores de Tempo
17.
J Sports Sci ; 37(1): 67-73, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29851551

RESUMO

This study investigated the validity and reliability of the GymAware PowerTool (GPT). Thirteen resistance trained participants completed three visits, consisting of three repetitions of free-weight back squat, bench press, deadlift (80% one repetition maximum), and countermovement jump. Bar displacement, peak and mean velocity, peak and mean force, and jump height were calculated using the GPT, a three-dimensional motion capture system (Motion Analysis Corporation; 150 Hz), and a force plate (Kistler; 1500 Hz). Least products regression were used to compare agreeability between devices. A within-trial one-way ANOVA, typical error (TE; %), and smallest worthwhile change (SWC) were used to assess reliability. Regression analysis resulted in R2 values of >0.85 for all variables excluding deadlift mean velocity (R2 = 0.54-0.69). Significant differences were observed between visits 3-2 for bench press bar displacement (0.395 ± 0.055 m; 0.383 ± 0.053 m), and deadlift bar displacement (0.557 ± 0.034 m; 0.568 ± 0.034 m). No other significant differences were found. Low to moderate TE (0.6-8.8%) were found for all variables, with SWC ranging 1.7-7.4%. The data provides evidence that the GPT can be used to measure kinetic and kinematic outputs, however, care should be taken when monitoring deadlift performance.


Assuntos
Treinamento Resistido/instrumentação , Adulto , Fenômenos Biomecânicos , Humanos , Reprodutibilidade dos Testes , Treinamento Resistido/métodos , Estudos de Tempo e Movimento , Adulto Jovem
18.
J Appl Clin Med Phys ; 20(6): 125-133, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31112629

RESUMO

PURPOSE: The purpose of this work was to compare the dosimetry and delivery times of 3D-conformal (3DCRT)-, volumetric modulated arc therapy (VMAT)-, and tomotherapy-based approaches for spatially fractionated radiation therapy for deep tumor targets. METHODS: Two virtual GRID phantoms were created consisting of 7 "target" cylinders (1-cm diameter) aligned longitudinally along the tumor in a honey-comb pattern, mimicking a conventional GRID block, with 2-cm center-to-center spacing (GRID2 cm ) and 3-cm center-to-center spacing (GRID3 cm ), all contained within a larger cylinder (8 and 10 cm in diameter for the GRID2 cm and GRID3 cm , respectively). In a single patient, a GRID3 cm structure was created within the gross tumor volume (GTV). Tomotherapy, VMAT (6 MV + 6 MV-flattening-filter-free) and multi-leaf collimator segment 3DCRT (6 MV) plans were created using commercially available software. Two tomotherapy plans were created with field widths (TOMO2.5 cm ) 2.5 cm and (TOMO5 cm ) 5 cm. Prescriptions for all plans were set to deliver a mean dose of 15 Gy to the GRID targets in one fraction. The mean dose to the GRID target and the heterogeneity of the dose distribution (peak-to-valley and peak-to-edge dose ratios) inside the GRID target were obtained. The volume of normal tissue receiving 7.5 Gy was determined. RESULTS: The peak-to-valley ratios for GRID2 cm /GRID3 cm /Patient were 2.1/2.3/2.8, 1.7/1.5/2.8, 1.7/1.9/2.4, and 1.8/2.0/2.8 for the 3DCRT, VMAT, TOMO5 cm , and TOMO2.5 cm plans, respectively. The peak-to-edge ratios for GRID2 cm /GRID3 cm /Patient were 2.8/3.2/5.4, 2.1/1.8/5.4, 2.0/2.2/3.9, 2.1/2.7/5.2 and for the 3DCRT, VMAT, TOMO5 cm , and TOMO2.5 cm plans, respectively. The volume of normal tissue receiving 7.5 Gy was lowest in the TOMO2.5 cm plan (GRID2 cm /GRID3 cm /Patient = 54 cm3 /19 cm3 /10 cm3 ). The VMAT plans had the lowest delivery times (GRID2 cm /GRID3 cm /Patient = 17 min/8 min/9 min). CONCLUSION: Our results present, for the first time, preliminary evidence comparing IMRT-GRID approaches which result in high-dose "islands" within a target, mimicking what is achieved with a conventional GRID block but without high-dose "tail" regions outside of the target. These approaches differ modestly in their ability to achieve high peak-to-edge ratios and also differ in delivery times.


Assuntos
Neoplasias/radioterapia , Órgãos em Risco/efeitos da radiação , Imagens de Fantasmas , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/métodos , Software , Humanos , Dosagem Radioterapêutica
19.
Br J Haematol ; 183(5): 747-754, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30407619

RESUMO

Chronic lymphocytic leukaemia (CLL) is characterized by expression of CD5 on clonal B cells, and is partly driven by activated B-cell receptor (BCR) signalling. While CD5 is known to be a negative regulator of BCR signalling, it is unknown if variability in CD5 expression exists among patients and whether CLL cell CD5 expression affects CLL clinical outcomes. We assessed the extent to which CD5 expression is correlated with clinical outcomes, and whether this information adds to currently used prognostic markers. We evaluated CD5 expression from 1275 blood samples, established prognostic markers and time to event data from 423 CLL patients followed at the Duke University and Durham VA Medical Centers. CD5 median fluorescence intensity (MFI) was largely stable over time in individual patients, but ranged between 0·5 and 760 in the entire cohort. Lower CD5 MFI was significantly associated with a shorter time to first therapy. CD5 MFI, combined with established clinical and molecular prognostic markers, significantly improved risk-stratification. CD5 may affect disease outcomes by suppressing signalling through the BCR. Thus, a strategy to modulate CLL cell CD5 expression or function could be a therapeutic approach in CLL.


Assuntos
Antígenos CD5/metabolismo , Leucemia Linfocítica Crônica de Células B/terapia , Receptores de Antígenos de Linfócitos B/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos B/metabolismo , Biomarcadores Tumorais/metabolismo , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/sangue , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Transdução de Sinais/fisiologia , Virginia/epidemiologia
20.
Environ Microbiol ; 20(12): 4596-4611, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30394652

RESUMO

About 60% of natural gas production in the United States comes from hydraulic fracturing of unconventional reservoirs, such as shales or organic-rich micrites. This process inoculates and enriches for halotolerant microorganisms in these reservoirs over time, resulting in a saline ecosystem that includes methane producing archaea. Here, we survey the biogeography of methanogens across unconventional reservoirs, and report that members of genus Methanohalophilus are recovered from every hydraulically fractured unconventional reservoir sampled by metagenomics. We provide the first genomic sequencing of three isolate genomes, as well as two metagenome assembled genomes (MAGs). Utilizing six other previously sequenced isolate genomes and MAGs, we perform comparative analysis of the 11 genomes representing this genus. This genomic investigation revealed distinctions between surface and subsurface derived genomes that are consistent with constraints encountered in each environment. Genotypic differences were also uncovered between isolate genomes recovered from the same well, suggesting niche partitioning among closely related strains. These genomic substrate utilization predictions were then confirmed by physiological investigation. Fine-scale microdiversity was observed in CRISPR-Cas systems of Methanohalophilus, with genomes from geographically distinct unconventional reservoirs sharing spacers targeting the same viral population. These findings have implications for augmentation strategies resulting in enhanced biogenic methane production in hydraulically fractured unconventional reservoirs.


Assuntos
Fraturamento Hidráulico , Methanosarcinaceae/fisiologia , Ecossistema , Genoma Bacteriano , Metagenoma , Methanosarcinaceae/genética , Gás Natural , Campos de Petróleo e Gás
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