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1.
Phys Rev Lett ; 124(4): 043201, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32058761

RESUMO

We theoretically and experimentally investigate the photon momentum transfer in single-photon double ionization of helium at various large photon energies. We find that the forward shifts of the momenta along the light propagation of the two photoelectrons are roughly proportional to their fraction of the excess energy. The mean value of the forward momentum is about 8/5 of the electron energy divided by the speed of light. This holds for fast and slow electrons despite the fact that the energy sharing is highly asymmetric and the slow electron is known to be ejected by secondary processes of shake off and knockout rather than directly taking its energy from the photon. The biggest deviations from this rule are found for the region of equal energy sharing where the quasifree mechanism dominates double ionization.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32059578

RESUMO

We theorized and tested a leader-member perspective beyond the existing studies in paradoxical leadership and employee voice behavior. We proposed that paradoxical leadership influences employees' voice behavior through psychological safety and self-efficacy. We also theorized that team size influences an extent to which the subordinates internalize their self-efficacy and psychological safety to exhibit proactive behavior. In a longitudinal study conducted on 155 subordinates and 96 supervisors in China, we found that when leaders adopt paradoxical behavior, employees are more likely to engage into promotive voice behavior; however, employees' prohibitive voice behavior is reduced when their leaders adopt paradoxes in leadership behavior. Additionally, psychological safety mediates the relationship between paradoxical leadership and promotive voice behavior. Further, team size has significant interaction effects with psychological safety on promotive voice behavior.

4.
AIDS Res Ther ; 17(1): 4, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32033564

RESUMO

OBJECTIVES: For migrant female sex workers (FSWs) at the Sino-Vietnamese border, the impact of work time in their current location on the spread of HIV/AIDS is not clear. METHODS: Data were collected from the Sino-Vietnamese border cities of Guangxi, China. Migrant FSWs working in these cities were studied. FSWs who worked less than 6 months in their current location were assigned to the short-term work group (ST FSWs), and FSWs who worked equal to or longer than 6 months in their current location were assigned to the long-term work group (LT FSWs). Logistic regression was performed to examine the impact of work time in the current location and factors associated with HIV infection. RESULTS: Among the 1667 migrant FSWs, 586 (35.2%) and 1081 (64.9%) were assigned to the ST FSW and LT FSW groups, respectively. Compared to LT FSWs, ST FSWs were more likely to be of Vietnamese nationality, be less than 18 years old when they first engaged in commercial sex work, and have a low-level of HIV-related knowledge and had higher odds of using condoms inconsistently, having more male clients, having no regular male clients, and having a history of male clients who used aphrodisiacs but lower odds of receiving free condoms distribution and education/HIV counselling and testing programme. The analysis of factors associated with HIV infection revealed that Vietnamese FSWs, less than 18 years old when they first engaged in commercial sex work, having no regular male clients, and having lower average charge per sex transaction were correlated with HIV infection. CONCLUSION: FSWs with short-term work at the Sino-Vietnamese border had a higher risk of risky sex and were correlated with HIV risk factors. Vietnamese FSWs were at higher risk of HIV infection, and they were more likely to have short-term work. More targeted HIV prevention should be designed for new FSWs who recently began working in a locality to further control the spread of HIV, particularly cross-border FSWs.

5.
J Biochem Mol Toxicol ; : e22473, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32048404

RESUMO

γ-Aminobutyrate (GABA) is commonly used as a food supplement and a health care product by young females, due to its positive roles in relieving stress, alleviating anxiety, and improving sleep. However, its recommended daily dose in different products varies widely. Besides, it is unknown whether, and how, GABA consumption during early pregnancy influences pregnancy establishment. In this study, we found that when pregnant mice were treated with a high (12.5 mg/g) dose of GABA (orally) during preimplantation, there was a reduction in the number of implantation sites on day 5 of pregnancy. Also, among these unimplanted embryos, most exhibited morphological degeneration and developmental retardation, and only a few of them developed into blastocysts but could not implant into the uterus. Moreover, the expression of uterine receptivity-related factors-LIF, E-cadherin, and HOXA10-were all downregulated, while the number of uterine glands was reduced in the high GABA dose group. Finally, in vitro results demonstrated that GABA (ranging from 10 to 50 µg/µL) markedly inhibited preimplantation embryo development in a dose-response manner. However, this inhibitory effect was not observed when the embryos were pretreated with 40 µΜ 2-hydroxysaclofen, a GABAB antagonist, indicating that GABA exerts its inhibitory effects via its B-type receptor. Our results suggest that exposure to certain GABA concentrations, during early pregnancy, can impair preimplantation embryo development via its B-type receptor, and endometrial receptivity, which greatly disturbs early embryo implantation in mice. These findings could raise concerns about GABA consumption during the early stages of pregnancy.

6.
Small ; : e1905223, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32049431

RESUMO

Designing elaborate nanostructures and engineering defects have been promising approaches to fabricate cost-efficient electrocatalysts toward overall water splitting. In this work, a controllable Prussian-blue-analogue-sacrificed strategy followed by an annealing process to harvest defect-rich Ni-Fe-doped K0.23 MnO2 cubic nanoflowers (Ni-Fe-K0.23 MnO2 CNFs-300) as highly active bifunctional catalysts for oxygen and hydrogen evolution reactions (OER and HER) is reported. Benefiting from many merits, including unique morphology, abundant defects, and doping effect, Ni-Fe-K0.23 MnO2 CNFs-300 shows the best electrocatalytic performances among currently reported Mn oxide-based electrocatalysts. This catalyst affords low overpotentials of 270 (320) mV at 10 (100) mA cm-2 for OER with a small Tafel slope of 42.3 mV dec-1 , while requiring overpotentials of 116 and 243 mV to attain 10 and 100 mA cm-2 for HER respectively. Moreover, Ni-Fe-K0.23 MnO2 CNFs-300 applied to overall water splitting exhibits a low cell voltage of 1.62 V at 10 mA cm-2 and excellent durability, even superior to the Pt/C||IrO2 cell at large current density. Density functional theory calculations further confirm that doping Ni and Fe into the crystal lattice of δ-MnO2 can not only reinforce the conductivity but also reduces the adsorption free-energy barriers on the active sites during OER and HER.

7.
AIDS Care ; : 1-9, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32008356

RESUMO

China's HIV/AIDS epidemic continues to grow in rural and less developed areas. This consecutive cross-sectional study examines demographic and behavioral factors associated with HIV/STI infection, Hepatitis C (HCV) and other sexually transmitted infections (STIs) among Vietnamese female sex workers (FSW), a vulnerable population who cross into Guangxi, China. This study is a secondary data analysis of 303 Vietnamese and 4,348 Chinese FSWs recruited over seven years from two Chinese counties that border Vietnam. Logistic regression models compared demographics, HIV/STI status, HIV/AIDS-related knowledge, attitudes, and risk behaviors between Vietnamese FSWs and Chinese FSWs. Compared with Chinese FSWs, Vietnamese FSWs were younger, had attained lower education levels, were highly mobile, more likely to report using drugs, and were more vulnerable to HIV/STIs. Younger age, less educational attainment, shorter time in their current working location, no voluntary HIV testing in the last year, greater drug use, and not using condoms for all commercial sex in the last month were associated with higher HIV/STIs. In conclusion, several factors were associated with HIV/STI risk in Vietnamese cross-border FSWs. There is a pressing need to improve support systems for Vietnamese cross-border FSW and health system cooperation across the Chinese/Vietnamese border.

8.
Antiviral Res ; 174: 104704, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31917237

RESUMO

AIMS: Deguelin, a natural compound derived from Mundulea sericea (Leguminosae) and some other plants exhibits an activity to inhibit autophagy, a cellular machinery required for hepatitis C virus (HCV) replication. This study aimed to illuminate the impact of deguelin on HCV replication and mechanism(s) involved. METHODS: HCV JFH-1-Huh7 infectious system was used for the investigation. Real time RT-PCR, Western blot, fluorescent microscopy assay were used to measure the expression levels of viral or cellular factors. Overexpression and silencing expression techniques were used to determine the role of key cellular factors. RESULTS: Deguelin treatment of Huh7 cells significantly inhibited HCV JFH-1 replication in a dose- and time-dependent manner. Deguelin treatment suppressed autophagy in Huh7 cells, evidenced by the decrease of LC3B-II levels, the conversion of LC3B-I to LC3B-II, and the formation of GFP-LC3 puncta as well as the increase of p62 level in deguelin-treated cells compared with control cells. HCV infection could induce autophagy which was also suppressed by deguelin treatment. Mechanism research reveals that deguelin inhibited expression of Beclin1, which is a key cellular factor for the initiation of the autophagosome formation in autophagy. Overexpression or silencing expression of Beclin1 in deguelin-treated Huh7 cells could weaken or enhance the inhibitory effect on autophagy by deguelin, respectively, and thus partially recover or further inhibit HCV replication correspondingly. CONCLUSIONS: Deguelin may serve as a novel anti-HCV compound via its inhibitory effect on autophagy, which warrants further investigation as a potential therapeutic agent for HCV infection.

9.
Phys Rev Lett ; 124(1): 010502, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31976724

RESUMO

Ensuring the nonentanglement-breaking (non-EB) property of quantum channels is crucial for the effective distribution and storage of quantum states. However, a practical method for direct and accurate certification of the non-EB feature is highly desirable. Here, we propose and verify a realistic source based measurement device independent certification of non-EB channels. Our method is resilient to repercussions on the certification from experimental conditions, such as multiphotons and imperfect state preparation, and can be implemented with an information incomplete set. We achieve good agreement between experimental outcomes and theoretical predictions, which is validated by the expected results of the ideal semiquantum signaling game, and accurately certify the non-EB channels. Furthermore, our approach is highly robust to effects from noise. Therefore, the proposed approach can be expected to play a significant role in the design and evaluation of realistic quantum channels.

10.
Ultrastruct Pathol ; : 1-13, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31906762

RESUMO

To clarify foam cell origination in atherosclerosis, a series of morphologic and ultrastructural alterations of vascular smooth muscle cells (VSMCs) and foam cells were studied by light and electron microscopy in atherosclerotic aortas from hyperlipidemic rabbits induced for 5 weeks. The study exhibited that VSMCs were severely degenerated and damaged, including irregular shapes, expanded mitochondria, aplenty lipid droplets, and disarranged myofilaments in cytoplasm in media adjacent to atheromatic bottoms. Most lipid laden cells shared interphase structures of VSMCs and foam cells, and some dissolved spindle cells contained lipid droplets, lipofuscin, and rod-like CCs in cytoplasm also. The result demonstrated that VSMCs were degenerated and transformed into foam cells in atherosclerosis, which was responsible for the accumulation of lipid and cholesterol crystals in atherosclerotic arteries.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31936800

RESUMO

This study aimed to explore the prevalence and influencing factors of anxiety and depression among human immunodeficiency virus negative (HIV-negative) men who have sex with men (MSM) based on anal sex roles, so as to provide a scientific basis for the management of mental health conditions. Data were obtained from the baseline in a cohort study with a two-year follow-up period in western China. The Self-Rating Anxiety Scale and Center for Epidemiological Studies Depression Scale were used to assess anxiety and depression symptoms, respectively. The prevalence of anxiety and depression in 1771 MSM was 26.03% and 37.83%. Among them, 182 anal sex role "0" MSM who only had receptive anal sex with men reported the highest prevalence of anxiety and depression (31.32% and 46.15%), 467 anal sex role "1" MSM who only had insertive anal sex with men (22.27% and 32.76%), and 1122 anal sex role "0.5" MSM who engaged equally in both insertive and receptive anal sex intercourse with men (26.74% and 38.59%), respectively. Logistic regression analysis revealed that the influencing factors of anxiety include anal sex role "0"/"0.5", low educational level, female sexual partners, frequently searching partners on the Internet, sexually transmitted diseases (STD) diagnosed by doctors, and no HIV counseling. Anal sex role "0"/"0.5", rural area, casual male partners, female partners, STD diagnosed by doctors, frequently searching partners on the Internet, no HIV counseling, no condom use, and daily alcohol use were found to be associated with depression. In conclusion, early identification and intervention of anxiety and depression symptoms in HIV-negative MSM should be carried out, especially for anal sex role "0" MSM. Furthermore, key intervention and psychological counseling should be taken into consideration for MSM with a low education level, high-risk behaviors, and high-risk perceptions.

13.
Medicine (Baltimore) ; 99(4): e18879, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31977893

RESUMO

RATIONALE: Myiasis is a parasitic disease caused by fly larvae of the Diptera order that infest human and other vertebrate animal tissues. Orbital myiasis is a potentially destructive infestation of the orbital tissues, which may affect individuals with previous ocular diseases or disorders of consciousness. PATIENT CONCERNS: A 72-year-old man presented with a complaint of repeated pain for two years after trauma to his right eyelid and aggravated symptoms with larvae wriggling out for 2 days. An orbital computed tomography scan revealed right eyeball protrusion and periocular soft tissue edema. Two days later, magnetic resonance imaging showed that the shape of the right eyeball was changed and that the normal structure of the eyeball could not be identified. DIAGNOSES: Due to the patient's symptoms and imaging examination results, the diagnosis of orbital myiasis was made. INTERVENTIONS: The patient was treated by exenteration of the right orbit, and all necrotic tissues and larvae were removed. The defect was repaired via reconstruction with a pedicled musculocutaneous flap from the forehead region. Antibiotics and tetanus toxoid therapy were utilized to prevent potential bacterial infection. OUTCOMES: The patient recovered well postoperatively and was discharged uneventfully. During the 6-month follow-up period, the wound healed well. LESSONS: Advanced age and untreated eye trauma are risk factors for orbital myiasis. Timely removal of larvae and elimination of infections are important measures for protecting the eyeball.


Assuntos
Enucleação Ocular/métodos , Miíase/cirurgia , Doenças Orbitárias/cirurgia , Idoso , Animais , Dípteros , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Miíase/diagnóstico , Doenças Orbitárias/diagnóstico por imagem
14.
Sci Total Environ ; 707: 135603, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-31784156

RESUMO

Recent studies have illustrated an association between ambient fine particulate matter (PM2.5) exposure and neuronal toxicity in epidemiological studies and animal models. However, the possible molecular effects on brains under real-world exposure to PM2.5 remain unclear. In this pilot study, male spontaneously hypertensive rats were whole-bodily exposed to ambient air from the outdoor environment of Taipei City for 3 months, while the control rats inhaled HEPA-filtered air. The PM2.5-induced phosphatidylcholine and sphingomyelin profiles in the hippocampus, cortex, medulla, cerebellum, and olfactory bulb were assessed by mass spectrometry (MS)-based lipidomics. Partial least squares discriminant analysis (PLS-DA) and the Wilcoxon rank sum test were used to examine the lipid changes between the exposed and control groups. The PLS-DA models showed that phosphatidylcholine and sphingomyelin profiles of the PM2.5 exposure group were different from those of the control group in each brain region except the cortex. More lipid changes were found in the hippocampus, while fewer lipid changes were observed in the olfactory bulb. The lipid alteration in the hippocampus may strengthen membrane integrity, modulate signaling pathways, and avoid accumulation of lipofuscin to counter the PM2.5-induced stress. The lipid changes in the cortex and medulla may respond to PM2.5-induced injury and inflammation; while the lipid changes in the cerebellum were associated with neuron protection. This study suggests that the MS-based lipidomics is a powerful approach to discriminate the brain lipid profiles even at the environmental level of ambient PM2.5 and has the potential to suggest possible adverse health effects in long-term PM2.5 exposure studies.

15.
Mol Cell Probes ; 49: 101491, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31812713

RESUMO

Homeodomain-containing gene C10 (HOXC10), known to regulate cell differentiation and proliferation, is a key negative regulator in the browning of white adipose tissue in mice. Sheep is an important farm animal that provides meat for human consumption, with fat content being an important meat quality determinant; however, there is no report about the role of HOXC10 in sheep adipocytes or adipogenesis. In this study, we investigated the effect of HOXC10 on proliferation and adipogenic differentiation in sheep bone marrow mesenchymal stem cells (sBMSCs). In sBMSCs, HOXC10 overexpression promoted cell proliferation and upregulated the expression of p-PI3K, p-AKT, p-p70S6K, p-MEK, and p-ERK, whereas HOXC10 knockdown was associated with the opposite effects. These results suggested that HOXC10 may promote cell proliferation by activating the MEK/ERK and PI3K/AKT/mTOR/p70S6K signaling pathways. In addition, we found that HOXC10 expression was negatively associated with lipid accumulation in adipogenic-differentiated sBMSCs. HOXC10 overexpression in sBMSCs significantly decreased lipid droplet accumulation and suppressed the expression of adipogenic-specific genes, including ACC, LPL, PPARG, and FABP4, while HOXC10 knockdown was associated with the opposite effects. Furthermore, our study suggested a new regulatory mechanism of the effect of HOXC10 on lipid accumulation and metabolism; HOXC10 may negatively regulate lipid accumulation in adipogenic-differentiated sBMSCs, at least in part, by suppressing LPL expression. Overall, our research not only contributes to a better understanding of the mechanism of lipid accumulation and metabolism in sheep, but also shed light on meat quality control in the future.

16.
Pancreatology ; 20(1): 16-24, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31806503

RESUMO

BACKGROUND/OBJECTIVES: Gut microbiota alterations in chronic pancreatitis (CP) are seldomly described systematically. It is unknown whether pancreatic exocrine insufficiency (PEI) and different etiologies in patients with CP are associated with gut microbiota dysbiosis. METHODS: The fecal microbiota of 69 healthy controls (HCs) and 71 patients with CP were compared to investigate gut microbiome alterations in CP and the relationship among gut microbiome dysbiosis, PEI and different etiologies. Fecal microbiomes were analyzed through 16S ribosomal RNA gene profiling, based on next-generation sequencing. Pancreatic exocrine function was evaluated by determining fecal elastase 1 activity. RESULTS: Patients with CP showed gut microbiota dysbiosis with decreased diversity and richness, and taxa-composition changes. On the phylum level, the gut microbiome of the CP group showed lower Firmicutes and Actinobacteria abundances than the HC group and higher Proteobacteria abundances. The abundances of Escherichia-Shigella and other genera were high in gut microbiomes in the CP group, whereas that of Faecalibacterium was low. Kyoto Encyclopedia of Genes and Genomes pathways (lipopolysaccharide biosynthesis and bacterial invasion of epithelial cells) were predicted to be enriched in the CP group. Among the top 5 phyla and 8 genera (in terms of abundance), only Fusobacteria and Eubacterium rectale group showed significant differences between CP patients, with or without PEI. Correlation analysis showed that Bifidobacterium and Lachnoclostridium correlated positively with fecal elastase 1 (r = 0.2616 and 0.2486, respectively, P < 0.05). CONCLUSIONS: The current findings indicate that patients with CP have gut microbiota dysbiosis that is partly affected by pancreatic exocrine function.

17.
Andrologia ; 52(1): e13473, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31746051

RESUMO

To explore the efficacy of regular penis-root masturbation (PRM) versus Kegel exercise (KE) in the treatment of primary premature ejaculation (PPE). This study was a prospective quasi-randomised controlled trial. Thirty-seven heterosexual males with PPE were selected according to the time sequence of outpatient consultations and the preliminary results of a pre-experiment and were assigned to an PRM group and a KE group. Differences in intravaginal ejaculatory latency times (IELTs) and premature ejaculation diagnostic tool (PEDT) scores were compared between the two groups. The study was approved by the Ethics Committee of the First Affiliated Hospital of Guangxi Medical University. Among the 37 PPE patients, 18 performed PRM and 19 patients performed KE. The IELTs of patients who performed PRM and KE were significantly prolonged before treatment, and the difference after treatment was statistically significant (p < .05). Compared with the KE group, the IELT prolongation effect in the PRM group was more significant PRM (p < .05). The PEDT scores of patients after performing PRM and KE were significantly lower than those before performing these exercises (p < .05). Compared with the KE group, the PEDT scores of the PRM group exhibited a greater decrease (p < .05). Thus, both PRM and KE have therapeutic effects on PPE. Compared with KE, PRM is more effective in the treatment of PPE.

18.
J Gastroenterol ; 55(1): 127-128, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31559487
19.
J Environ Sci (China) ; 88: 103-111, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31862051

RESUMO

In this study, we report a novel magnetic biomimetic nanozyme (Fe3O4@Cu/GMP (guanosine 5'-monophosphate)) with high laccase-like activity, which could oxidize toxic o-phenylenediamine (OPD) and remove phenolic compounds. The magnetic laccase-like nanozyme was readily obtained via complexed Cu2+ and GMP that grew on the surface of magnetic Fe3O4 nanoparticles. The prepared Fe3O4@Cu/GMP catalyst could be magnetically recycled for at least five cycles while still retaining above 70% activity. As a laccase mimic, Fe3O4@Cu/GMP had more activity and robust stability than natural laccase for the oxidization of OPD. Fe3O4@Cu/GMP retained about 90% residual activity at 90°C and showed little change at pH 3-9, and the nanozyme kept its excellent activity after long-term storage. Meanwhile, Fe3O4@Cu/GMP had better activity for removing phenolic compounds, and the removal of naphthol was more than 95%. Consequently, the proposed Fe3O4@Cu/GMP nanozyme shows potential for use as a robust catalyst for applications in environmental remediation.

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 117894, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31865100

RESUMO

A novel fluorescence probe (DNA-AgNCs) was synthesized for dually detecting hydrogen peroxide (H2O2) and ferrous ion (Fe(II)) in water samples. The assay is carried out through a dramatic "turn-off" fluorescence response of AgNCs by hydroxyl radical (OH), which is produced when H2O2 and Fe(II) are present simultaneously. Under the optimal conditions, the degree of fluorescence quenching of the DNA-AgNCs at 525 nm is linearly related to the concentration of H2O2 in the range of 0.3 to 450 pM, and Fe(II) in the range of 0.2 to 6.0 µM. The limit of detection (LOD) of H2O2 and Fe(II) are as low as 99 fM and 60 nM, respectively. Moreover, this method has the advantages of good specificity, high sensitivity, and can be successfully applied for detecting H2O2 and Fe(II) in the real water samples.

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