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1.
Appl Opt ; 58(30): 8148-8152, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674484

RESUMO

In this work, we report a large-active-area multispectral superconducting nanowire single-photon detector for free-space applications. The detector is realized by fabricating NbTiN nanowire with an active area of 35 µm diameter on two serially connected dielectric mirrors that can simultaneously and efficiently detect single photons at the three typical wavelengths employed in free-space applications, namely, 532, 850, and 1064 nm. Maximal system detection efficiencies (SDEs) of 80.0% at 532 nm and 850 nm and 75.8% at 1064 nm are achieved for polarized light obtained by coupling the detector with an SMF-28 fiber. Upon coupling with a 50 µm multimode fiber, SDEs of 68.6%, 59.6%, and 47.0%, are achieved for 532, 850, and 1064 nm wavelength unpolarized light, respectively. Moreover, the detector shows timing jitters of 37.1 and 41.0 ps when coupled with SMF-28 fiber and 50 µm multimode fiber. This type of detector with a large active area and multiwavelength detection capability is promising for both single and multiwavelength free-space applications.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31644788

RESUMO

BACKGROUND: Older adults with chronic kidney disease (CKD)-discordant conditions (comorbid conditions with treatment recommendations that potentially complicate CKD management) have greater risk of hospitalization and death. Our goal was to develop a CKD-Discordance Index using electronic health records to improve recognition of discordance. METHODS: This retrospective cohort included Kaiser Permanente Southern California patients aged ≥65 years with incident CKD (N=30,932). To guide inclusion of conditions in the Index and weight each condition, we first developed a prediction model for 1-year hospitalization risk using Cox regression. Points were assigned proportional to regression coefficients derived from the model. Next, the CKD-Discordance Index was calculated as an individual's total points divided by the maximum possible discordance points. The association between CKD-Discordance Index and hospitalizations, ED visits, and mortality was accessed using multivariable adjusted Cox regression. RESULTS: Overall, mean (SD) age was 77.9 (7.6), 55% were female, 59.3% were white, and 32% (n=9,869) had ≥1 hospitalization during 1 year of follow-up. The CKD-Discordance Index included the following: heart failure, gastroesophageal reflux disease/peptic ulcer disease, osteoarthritis, dementia, depression, cancer, chronic obstructive pulmonary disease/asthma, and having ≥4 prescribers. Compared to those with a CKD-Discordance Index of 0, adjusted hazard ratios (95% CI) for hospitalization were 1.39 (1.27-1.51) and 1.81 (1.64-2.01) for those with a CKD-Discordance Index of 0.001-0.24 and ≥0.25, respectively (Ptrend<0.001). A graded pattern of risk was seen for ED visits and all-cause mortality. CONCLUSION: A data-driven approach identified CKD-discordant indicators for a CKD-Discordance Index. Higher CKD-Discordance Index was associated with healthcare utilization and mortality.

3.
Neuroimage ; : 116287, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31655111

RESUMO

Rumination is strongly and consistently correlated with depression. Although multiple studies have explored the neural correlates of rumination, findings have been inconsistent and the mechanisms underlying rumination remain elusive. Functional brain imaging studies have identified areas in the default mode network (DMN) that appear to be critically involved in ruminative processes. However, a meta-analysis to synthesize the findings of brain regions underlying rumination is currently lacking. Here, we conducted a meta-analysis consisting of experimental tasks that investigate rumination by using Signed Differential Mapping of 14 fMRI studies comprising 286 healthy participants. Furthermore, rather than treat the DMN as a unitary network, we examined the contribution of three DMN subsystems to rumination. Results confirm the suspected association between rumination and DMN activation, specifically implicating the DMN core regions and the dorsal medial prefrontal cortex subsystem. Based on these findings, we suggest a hypothesis of how DMN regions support rumination and present the implications of this model for treating major depressive disorder characterized by rumination.

4.
Fungal Genet Biol ; : 103285, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31648060

RESUMO

Protein O-mannosyltransferases (PMTs) have been identified in fungi but not in plants and nematodes, which makes PMTs become attractive targets for developing a new strategy against phytopathogens. Three PMTs have been identified in Fusarium oxysporum, a fungal pathogen that causes vascular wilt in a broad range of economical crops. By deletion or suppression of the pmt genes, we showed that all mutants displayed retarded growth, reduced conidiation, cell wall defects, ER stress and attenuated virulence in F. oxysporum f.sp. cucumerinum. In addition, the Δpmt1 exhibited reduced thermotolerance, while the Δpmt4 and the pmt2 conditional mutant exhibited abnormal polarized growth. Comparative glycoproteome analysis of these pmt mutants revealed that PMTs preferentially modified random coils with flanking regions rich in Ser, Thr, Ala, Glu, Asp and Lys at the stem region of membrane proteins, the N-terminal region close to signal peptide of secreted proteins, or surface of soluble proteins. PMT1 specifically acted on nuclear proteins and proteins that are responsible for protein folding, which might contribute to thermotolerance. PMT4 specifically acted on the membrane and soluble proteins in secretory pathways, especially the GPI anchoring pathway, which might contribute to synthesis and transportation of GPI anchored proteins and thus polarized growth. PMT2 was responsible for modification of proteins that are required for protein folding and cell wall synthesis, which might make PMT2 essential. Our results gave an insight to understanding of the roles of each O-mannosyltransferase in F. oxysporum f.sp. cucumerinum and provide a new perspective to prevent Fusarium wilt.

5.
Surgery ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31582307

RESUMO

BACKGROUND: Parathyroidectomy (PTX) increases bone mineral density and decreases fracture risk in patients with primary hyperparathyroidism. This study examined the effect of adding bisphosphonates either before or after PTX on skeletal outcomes. METHODS: A retrospective cohort study of bisphosphonate-naïve patients (1995-2016) with osteoporosis and primary hyperparathyroidism (calcium >10.5 mg/dL; PTH >65) was performed. Time-varying Cox regression was used to estimate an adjusted risk of any fracture in 5 comparison groups: observation, bisphosphonates alone, PTX alone, bisphosphonates then PTX, and PTX then bisphosphonates. The secondary outcome was change in bone mineral density of the hip. RESULTS: The cohort comprised 1,737 patients, of whom 303 underwent PTX (17%), 433 received bisphosphonates only (25%), 125 had bisphosphonates then PTX (7%), and 69 had PTX then bisphosphonates (4%). PTX was associated with a decrease in fracture risk (HR 0.55, 95% CI 0.35-0.84), as was bisphosphonates then PTX (HR 0.46, 95% CI 0.25-0.83). In contrast, the fracture risks associated with PTX then bisphosphonates (HR 1.09, 95% CI 0.65-1.81) and bisphosphonates alone (HR 0.82, 95% CI 0.62-1.08) were similar to observation. Hip bone mineral density increased after both PTX (5.50%, 95% CI 3.39-7.61) and PTX then bisphosphonates (6.30%, 95% CI 2.53-10.07). CONCLUSION: Bisphosphonate initiation after PTX may interfere with the beneficial effects of PTX on fracture risk in osteoporotic patients with primary hyperparathyroidism.

6.
Mol Genet Genomic Med ; : e994, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31617686

RESUMO

BACKGROUND: Long intergenic noncoding RNAs (lincRNAs) are a series of novel transcribed regions expressed in cancers that may represent candidate biomarkers for lung squamous cell carcinoma (LSqCC) treatment. In this study, we evaluated the lincRNA profile in LSqCC patients and screened valuable lincRNAs for diagnosis and prognosis. METHODS: Transcriptome profiling of 549 samples derived from 501 LSqCC patients were identified in TCGA database. 48 patients had paired primary tumor (PT) and solid normal (SN) tissue samples, while 453 patients had only PT samples. 1,771 lincRNA candidates were evaluated. Paired test (Wilcoxon two-sample paired signed rank tests) was performed in paired PT and SN samples. Logistic regression analysis were performed in independent 453 PT samples and 48 SN samples to screen the significant lincRNAs candidates for malignances. Independent 501 PT samples were further used to screen the significant lincRNAs candidates for prognosis. RESULTS: Among 1,771 lincRNAs, 10 lincRNAs were significant highly-expressed risk candidates in PT samples, and 10 protective lincRNAs candidates were significant lowly-expressed in PT samples. Among 10 highly-expressed risk lincRNAs, a small panel of LINC00487, LINC01927, and C10orf143 (LINC00959) could effectively predict malignancies in paired samples (AUC = 0.7274, 95%CI = (0.6264, 0.8285)). When combined with protective lincRNA candidates LINC02315, LINC00491, and LINC01697, the predictive efficiency was greatly improved in both paired samples (AUC = 0.8030, 95%CI = (0.7250, 0.8810)) and independent samples (AUC = 0.7481, 95%CI= (0.6642, 0.8320)). Additionally, three highly-expressed risk lincRNAs, LINC01031, LINC01088, and LINC01931, were significantly associated with poor prognosis in PT samples, suggesting potential targets for anti-LSqCC treatment. CONCLUSION: Therefore, lincRNAs could be promising biomarkers for predicting malignancies and potential anti-LSqCC targets for drug development.

8.
Aging (Albany NY) ; 11(19): 8169-8182, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31581133

RESUMO

Two-pore-domain (KCNK, K2P) K+ channels are transmembrane protein complexes that control the flow of ions across biofilms, which underlie many essential cellular functions. Because KCNK family members are known to contribute to tumorigenesis in various types of cancer, we hypothesized that they might be differentially expressed in hepatocellular carcinoma (HCC) cells as compared to healthy tissue and serve as diagnostic or prognostic biomarkers. We tested this hypothesis through bioinformatic analyses of publicly available data for the expression of various KCNK subunits in HCC. We observed reduced expression of KCNK2, KCNK15, and KCNK17 in liver cancer, as well as overexpression of KCNK9, all of which correlated with a better prognosis for HCC patients per survival analyses. Moreover, ROC curves indicated that KCNK2, KCNK9, KCNK15, and KCNK17 levels could be used as a diagnostic biomarker for HCC. Finally, our western blot and qRT-PCR results were consistent with those obtained from bioinformatic analyses. Taken together, these results suggest that KCNK2, KCNK9, KCNK15, and KCNK17 could serve as potential diagnostic and prognostic biomarkers of HCC.

9.
Eur J Pharmacol ; 864: 172725, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31604070

RESUMO

Dehydrocorydaline, is an active alkaloid compound in Corydalis yanhusuo W. T. Wang. We found dehydrocorydaline induced antidepressant-like effects in a chronic unpredictable mild stress mouse model, but the exact mechanisms have not been addressed. We speculated that dehydrocorydaline may have an antidepressant effect via inhibiting monoamine transporters in the brain. We evaluated the mechanism of action of dehydrocorydaline by examining the levels of monoamine transmitters (5-HT, NE and DA) in the prefrontal cortex in chronic unpredictable mild stress mice. Then, we used cell models and the mouse synaptosome to study molecular and cellular mechanisms underlying these behaviors and monoamine alterations by dehydrocorydaline. Our results indicated that dehydrocorydaline affects the concentrations of monoamine transmitters and decreases the turnover ratio, which indicates increased neuronal activity. The possible mechanism is that dehydrocorydaline potently inhibits uptake-2 transporters with the IC50 values of 0.1-4 µM and could inhibit the reuptake of 5-HT/DA/NE in the synaptosome. These data suggest that dehydrocorydaline has an antidepressant effect that is likely related to changing the content of monoamines in the brain by inhibiting uptake-2 transporters.

10.
Med Sci Monit ; 25: 7853-7863, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31630150

RESUMO

BACKGROUND Laryngeal cancer is one of the most common malignant tumors of the head and neck. Natural compounds in traditional Chinese medicine provide many valuable potential compounds for tumor chemotherapy. Esculetin, a coumarin derivative from several herbs, inhibits proliferation of many types of cancer cells, but its anticancer effect in laryngeal cancer is still not clear. MATERIAL AND METHODS We performed in vitro proliferation assay, invasion assay, and migration assay to assess the effect of esculetin against LC, and in vivo nude mouse xenograft animal model was used as well. Flow cytometry was conducted to analyze the effect of esculetin on cell cycle of LC cells, and Western blot analysis was used to assess the effect esculetin on the JAK-STAT signaling pathway. RESULTS Esculetin remarkably inhibits proliferation, migration, and invasion of LC cells, and reduces in vivo xenograft tumor growth and tumor weight in a dose-dependent manner. Our molecular mechanism study demonstrated that esculetin significantly inhibits STAT3 phosphorylation and blocks translocation of STAT3 into the nucleus, and esculetin also blocks the cell cycle in G1/S phase. CONCLUSIONS In a summary, by inhibiting the STAT3 activation, esculetin shows potential anticancer effects against the laryngeal cancer.

11.
Anesth Analg ; 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31633507
12.
Medicine (Baltimore) ; 98(37): e17010, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31517820

RESUMO

PURPOSE: To find out whether the intramedullary fixations are superior to the extramedullary fixations in treating unstable femoral intertrochanteric fractures (UFIFs). METHODS: The meta-analysis of randomized controlled trials (RCTs) was conducted by searching the PubMed, Cochrane Library, and Embase databases to evaluate functional scores, surgical outcomes, and adverse events in adult patients receiving intramedullary fixations in comparison to extramedullary fixations. Risk ratio (RR) or weighted mean difference (WMD)/standard mean difference (SMD) with 95% confidence intervals (CIs) were calculated as effect sizes. RESULTS: A total of 18 RCTs, comprising 2414 patients, were included in this meta-analysis. Primary efficacy outcome: Parker scores [weighted mean difference, 1.10, 95% confidence interval (CI), 0.64-1.55; P < .0001] and Harris hip scores [risk ratio, 1.24, 95%CI, 1.09 -1.41; P = .0008] were higher in the intramedullary fixation group. Moreover, blood loss, operative time, length of incision, hospital stay, and implant failure were superior in the intramedullary fixation group. Other secondary efficacy outcome: No significant differences were found between the 2 groups in terms of fluoroscopy time, mortality, cut-out, nonunion, superficial wound infection, later fracture, and reoperation. CONCLUSIONS: This meta-analysis suggested that intramedullary fixation is more effective and safer than extramedullary fixation in treating UFIFs. Furthermore, blood loss, operative time, length of incision, hospital stay, and implant failure were superior in the intramedullary fixation group.


Assuntos
Fraturas do Fêmur/cirurgia , Fixação Interna de Fraturas/métodos , Humanos , Complicações Pós-Operatórias , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Lab Chip ; 19(20): 3387-3396, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31517364

RESUMO

The patterning of nanoparticles, which are promising photothermal agents, is of great importance to selectively and precisely ablate tissues by thermal effects. In this paper, we demonstrated that nano-sized gold particles (gold nanocages, AuNCS) with a hollow structure could be used to generate various wavefront patterns of surface acoustic waves (SAWs) and the aligned AuNC lines facilitated the destruction of cancer cells by the thermal effect with high spatial resolution. The hollow structure improved the acoustic sensitivity of AuNCs, making them more sensitive to the acoustic radiation force. Moreover, the multi-scale patterning of AuNCs could be achieved by the interference of multiple acoustic beams. Given the photothermal characteristics of AuNCs, selective temperature elevation within a micrometer-sized region could be realized when the patterned AuNCs were irradiated by a laser. The cancer cells where the patterned AuNCs were located were eliminated by thermal ablation, while other cells remained alive. In particular, the acoustic frequency used in this study was as low as 11. 35 MHz and was in the range of diagnostic ultrasound (less than 12 MHz), offering a potential to serve as a powerful tool in clinical applications.

15.
EMBO Rep ; : e47650, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31486214

RESUMO

LTR retrotransposons are abundant repetitive elements in the human genome, but their functions remain poorly understood. Here, we report the function and regulatory mechanism of an ERV-9 LTR retrotransposon-derived lncRNA called p53-regulated lncRNA for homologous recombination (HR) repair 1 (PRLH1) in human cells. PRLH1 is highly expressed in p53-mutated hepatocellular carcinoma (HCC) samples and promotes cell proliferation in p53-mutated HCC cells, and its transcription is promoted by NF-Y and suppressed by p53. Mechanistically, PRLH1 specifically binds to an uncharacterized domain of RNF169 through two GCUUCA boxes in its 5' terminal region to form a DNA repair complex that supplants 53BP1 at double-strand break (DSB) sites and then promotes the initiation of HR repair. Notably, PRLH1 is essential for the stabilization of RNF169, acting as an RNA platform to recruit and assemble HR protein factors. This study characterizes PRLH1 as a novel HR-promoting factor and provides new insights into the function and mechanism of LTR retrotransposon-derived lncRNAs.

16.
Nat Commun ; 10(1): 4081, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501446

RESUMO

The efficiency of sunlight-driven reduction of carbon dioxide (CO2), a process mimicking the photosynthesis in nature that integrates the light harvester and electrolysis cell to convert CO2 into valuable chemicals, is greatly limited by the sluggish kinetics of oxygen evolution in pH-neutral conditions. Current non-noble metal oxide catalysts developed to drive oxygen evolution in alkaline solution have poor performance in neutral solutions. Here we report a highly active and stable oxygen evolution catalyst in neutral pH, Brownmillerite Sr2GaCoO5, with the specific activity about one order of magnitude higher than that of widely used iridium oxide catalyst. Using Sr2GaCoO5 to catalyze oxygen evolution, the integrated CO2 reduction achieves the average solar-to-CO efficiency of 13.9% with no appreciable performance degradation in 19 h of operation. Our results not only set a record for the efficiency in sunlight-driven CO2 reduction, but open new opportunities towards the realization of practical CO2 reduction systems.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31504538

RESUMO

OBJECTIVES: The authors aimed to clarify the incidence and risk factors of postoperative liver dysfunction (PLD) in patients undergoing total arch replacement combined with frozen elephant trunk implantation and to determine the association of PLD with short-term outcomes. METHODS: Data from 672 adult patients undergoing total arch replacement with frozen elephant trunk from January 2013 until December 2016 at Fuwai Hospital were analysed retrospectively. A multivariable logistic regression model was used to identify the risk factors for PLD. RESULTS: The overall incidence of PLD was 27.5%, which was associated with higher in-hospital mortality (PLD 4.9% vs No PLD 0.8%, P = 0.002) and 30-day mortality (PLD 9.2% vs No PLD 2.5%, P < 0.001) and a higher incidence of major adverse events (PLD 54.6% vs No PLD 23.4%, P < 0.001). In the multivariable analysis, preoperative hypotension [odds ratio (OR) 1.97, 95% confidence interval (CI) 1.14-3.41; P = 0.02), coronary artery disease (OR 2.64, 95% CI 1.17-5.96; P = 0.02), prolonged cardiopulmonary bypass duration (OR 1.01, 95% CI 1.00-1.01; P < 0.001), increased preoperative alanine transferase (OR 1.01, 95% CI 1.00-1.01; P < 0.001), preoperative platelet count <100 × 109/l (OR 3.99, 95% CI 1.74-9.14; P = 0.001) and increased intraoperative erythrocyte transfusion (OR 1.07, 95% CI 1.01-1.12; P = 0.02) were identified as independent risk factors for PLD. CONCLUSIONS: PLD was associated with increased mortality and morbidity. Among the independent risk factors for PLD, cardiopulmonary bypass duration and erythrocyte transfusion could be modifiable. A skilled surgical team and an ideal blood protection strategy may be helpful to protect liver function.

18.
Toxicol Lett ; 316: 183-193, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31437515

RESUMO

Olanzapine, a representative of antipsychotics, is a first-line drug for treatment of schizophrenia. However, olanzapine-induced liver steatosis limits its clinical utilization. This study is to explore the mechanism of liver steatosis induced by olanzapine based on the regulation of transporters involved in uptake and oxidation of fatty acids. Our results revealed that 12-week oral administration of olanzapine increased hepatic triglyceride(TG), caused liver steatosis. Our further studies showed that the expression of fatty acid transporter 2(FATP2) and fatty acid binding protein 1(FABP1) were up-regulated in liver of female mice after 12-week olanzapine exposure, as well as in primary mouse hepatocytes treated with olanzapine. Olanzapine treatment also reduced hepatic ß-hydroxybutyrate level (indicator of fatty acid ß-oxidation), meanwhile, the L-carnitine (L-Car) concentration in liver of olanzapine group was significantly lower than that in control group. Further study demonstrated that both mRNA and protein expression of hepatic OCTN2 (carnitine/organic cation transporter 2) were obviously down-regulated in male mice after 12-week olanzapine treatment. Also, olanzapine markedly inhibited L-Car uptake in MDCK-hOCTN2 cells (1.06 µM of IC50), HepG2 cells and primary mouse hepatocytes. Supplementation of L-Car attenuated hepatic TG rise and improved simple steatosis in olanzapine treatment mice. Taken together, up-regulation of FATP2/FABP1 and down-regulation/inhibition of hepatic OCTN2 probably contribute to olanzapine-induced liver steatosis. Supplementation of L-Car is a promising strategy to attenuate olanzapine-induced simple steatosis.


Assuntos
Antipsicóticos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Coenzima A Ligases/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo , Fígado Gorduroso/induzido quimicamente , Hepatócitos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Olanzapina/toxicidade , Membro 5 da Família 22 de Carreadores de Soluto/antagonistas & inibidores , Adulto , Animais , Carnitina/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Coenzima A Ligases/genética , Cães , Proteínas de Ligação a Ácido Graxo/genética , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Fígado Gorduroso/prevenção & controle , Feminino , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Fígado/metabolismo , Fígado/patologia , Células Madin Darby de Rim Canino , Masculino , Camundongos Endogâmicos C57BL , Membro 5 da Família 22 de Carreadores de Soluto/genética , Membro 5 da Família 22 de Carreadores de Soluto/metabolismo , Regulação para Cima
19.
ACS Appl Mater Interfaces ; 11(38): 34889-34894, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31466439

RESUMO

High-nickel layered oxides, such as NMC 811, are very attractive high energy density cathode materials. However, the high nickel content creates a number of challenges, including high surface reactivity and structural instability. Through a wet chemistry method, a Li-Nb-O coated and substituted NMC 811 was obtained in a single step treatment. This Li-Nb-O treatment not only supplied a protective surface coating but also optimized the electrochemical behavior by Nb5+ incorporation into the bulk structure. As a result, the 1st capacity loss was significantly reduced (13.7 vs 25.1 mA h/g), contributing at least a 5% increase to the energy density of the full cell. In addition, both the rate (158 vs 135 mA h/g at 2C) and capacity retention (89.6 vs 81.6% after 60 cycles) performance were enhanced.

20.
Nutr Rev ; 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31393566

RESUMO

CONTEXT: Excess weight has been linked to increased risks of 13 types of cancers. Physical activity is a non-nutritional modifiable lifestyle factor that is not only crucial for weight control but is also known to regulate hormones and metabolic pathways that may contribute to carcinogenesis. There is solid evidence that being physically active during middle and late adulthood lowers the risks of 3 obesity-related cancers, namely breast cancer, colon cancer, and endometrial cancer. However, the associations between physical activity at a young age (childhood, adolescence, and young adulthood; age 5 to ≤30 yr) and lifetime physical activity and the risks of breast cancer, colon cancer, and endometrial cancer are less defined. OBJECTIVE: The present systematic review and meta-analysis of observational studies was performed in accordance with the MOOSE guidelines to determine whether physical activity at a young age and lifetime physical activity may lower the risks of breast cancer, colon cancer, and endometrial cancer. DATA SOURCES: The PubMed and Web of Science databases were searched for relevant observational studies published from inception to July 2018. STUDY SELECTION: Observational studies (prospective cohort, case-cohort, nested case-control, historical cohort, and case-control) were considered relevant if they investigated the association between physical activity at a young age or lifetime physical activity and the risks of developing selected cancers. DATA EXTRACTION: A random-effects meta-analysis was performed to generate the summary relative risk (RR) with 95%CI for the highest vs the lowest category of physical activity of any type. RESULTS: Eighty publications were included in the present meta-analysis. Higher physical activity at a young age was associated with lower risks of breast cancer (RR 0.81, 95%CI 0.76, 0.87) and colon cancer (RR 0.67, 95%CI 0.50, 0.88). Similarly, lifetime physical activity was inversely associated with the risks of breast cancer (RR 0.79, 95%CI 0.72, 0.86) and colon cancer (RR 0.75, 95%CI 0.69, 0.82). For breast cancer, menopausal status did not appear to modify the observed inverse association. The benefit with respect to endometrial cancer risk reduction was only observed with higher lifetime physical activity (RR 0.77, 95%CI 0.67, 0.88), not with higher physical activity at a young age (RR 0.89, 95%CI 0.73, 1.07). CONCLUSIONS: Being physically active over a lifetime, starting from early childhood, may lower the risks of developing breast cancer, colon cancer, and endometrial cancer.

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