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1.
Zhonghua Yi Xue Za Zhi ; 100(1): 47-50, 2020 Jan 07.
Artigo em Chinês | MEDLINE | ID: mdl-31914558

RESUMO

Objective: To evaluate the clinical value of modified computed tomography angiography(CTA) in detecting bronchial artery-pulmonary artery fistula(BPF). Methods: Retrospective analysis was performed on 246 patients with hemoptysis admitted to the First Affiliated Hospital of Wenzhou Medical University from July 2017 to December 2018, who underwent modified CTA and DSA examination at the same time. CT was performed with Toshiba Aquilion one 320 row 640-slice spiral CT scanner. All modified CTA images were read blindly by two radiologists above the attending doctors. The sensitivity, specificity and accuracy of the modified CTA in diagnosing BPF were calculated with the DSA results as the reference,and the consistency of the two tests was analyzed. Results: DSA detected 186 cases of positive and 60 cases of negative, modified CTA detected 160 cases of positive and 86 cases of negative. The sensitivity,specificity and accuracy of modified CTA for BPF diagnosis was 85.5%(159/186),98.3%(59/60), 88.6%(218/246) respectively, and they were with high consistency with DSA examination results (kappa=0.73,P<0.01). Conclusion: Modified CTA has high diagnostic specificity for BPF,which can be used as the preferred method for non-invasive screening of suspected BPF patients.


Assuntos
Angiografia por Tomografia Computadorizada , Fístula , Artérias Brônquicas , Humanos , Artéria Pulmonar , Estudos Retrospectivos
2.
Clin Microbiol Infect ; 26(2): 247-254, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31229595

RESUMO

OBJECTIVES: Despite the importance of immunological memory for protective immunity against viral infection, whether H7N9-specific antibodies and memory T-cell responses remain detectable years after the original infection is unknown. METHODS: A cross-sectional study was conducted to investigate the immune memory responses of H7N9 patients who contracted the disease and survived during the 2013-2016 epidemics in China. Sustainability of antibodies and T-cell memory to H7N9 virus were examined. Healthy individuals receiving routine medical examinations in a physical examination centre were recruited as control. RESULTS: A total of 75 survivors were enrolled and classified into four groups based on the time elapsed from illness onset to specimen collection: 3 months (n = 14), 14 months (n = 14), 26 months (n = 28) and 36 months (n = 19). Approximately 36 months after infection, the geometric mean titres of virus-specific antibodies were significantly lower than titres in patients 3 months after infection, but 16 of 19 (84.2%) survivors in the 36-month interval had microneutralization (MN) titres ≥40. Despite the overall declining trend, the percentages of virus-specific cytokine-secreting memory CD4+ and CD8+ T cells remained higher in survivors at nearly all time-points in comparison with control individuals. Linear regression analysis showed that severe disease (mean titre ratio 2.77, 95% CI 1.17-6.49) was associated with higher haemagglutination inhibition (HI) titre and female sex for both HI (1.92, 1.02-3.57) and MN (3.33, 1.26-9.09) antibody, whereas female sex (mean percentage ratio 1.69, 95% CI 1.08-2.63), underlying medical conditions (1.94, 95% CI 1.09-3.46) and lack of antiviral therapy (2.08, 95% CI 1.04-4.17) were predictors for higher T-cell responses. CONCLUSIONS: Survivors of H7N9 virus infection produced long-term antibodies and memory T-cell responses. Our findings warrant further serological investigation in general and high-risk populations and have important implications for vaccine design and development.

3.
J Phys Condens Matter ; 32(3): 035402, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31557731

RESUMO

Recent experiments have demonstrated the existence of vortex or flux-closure domains in ferroelectric nanostructures, which are attractive to develop high-density data storage and novel configurable electronic devices. However, it remains challenging to stabilize in-plane vortex or flux-closure domains in ferroelectric film for the absence of a lateral geometry confinement. Based on a 3D phase field model, here we show that stabilization of isolated or interacting in-plane vortices in ferroelectric film can be achieved via applying a mechanical tip-force. The formation of such dipole vortices is caused by a conjoint effect of the tip-force-induced depolarization effect and in-plane strain. The effects of factors like film thickness, misfit strain, tip force and temperature on the vortex formation are systematically revealed and summarized as phase diagrams. The interaction between tip-induced vortices is also investigated. It is found that as the two tips get closer than the critical distance, the two initially isolated vortices become coupled, with identical or opposite chirality, depending on the distance between the two tips. A maximum data storage density of isolated in-plane vortices in ferroelectric thin film is estimated to be ~1 Tb in-2. Our work thus demonstrates a mechanical strategy to stabilize dipole vortices, and provides a comprehensive insight into the characteristics of ferroelectric film under a mechanical tip force.

4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(12): 1278-1283, 2019 Dec 06.
Artigo em Chinês | MEDLINE | ID: mdl-31795586

RESUMO

Objective: Using field epidemiological investigation and molecular analysis to construct the molecular transmission network of human immunodeficiency virus/acquired immunodeficiency syndrome cases (HIV/AIDS) newly diagnosed in Huzhou in 2017, Zhejiang Province. Methods: A total of 160 participants were obtained through a web-based system from Chinese Center for Disease Control and Prevention (CCDC) with the features of diagnosed in Huzhou in 2017 who also had been collected samples for the first follow-up. The basic information of demographic characteristics and risk factors was extracted from the website. RNA was extracted from plasma samples of untreated cases, followed by RT-PCR and nest-PCR for pol gene amplification, sequencing. Phylogenetic tree was constructed by MEGA software for HIV gene subtyping. TN93 model was used for calculating the distance between two sequences. Cytoscape software was used for drawing molecular transmission network. And then an epidemiological survey was conducted to cases in the primary cluster. Results: A total of 138 sequenced individuals (86.3%) were acquired from 160 individuals. Among which, 123 (89.1%) were male. The highest proportion of subtype was CRF07_BC (60, 43.5%), followed by CRF01_AE (46, 33.3%), and with four cases of Unique Recombinant Form (URF, CRF01_AE and CRF07_BC) and one case of URF (subtype B and C). A total of 18 molecular clusters included 56 individuals (40.6%) were found in the transmission network under the optimal genetic distance threshold (1.0%). The clustering proportion of CRF07_BC (66.1%, 37 cases) was higher than that of CRF01_AE. There were 9 clusters formed among CRF07_BC, including 37 cases (accounting for 61.7%, 37/60). The primary transmission cluster contained 11 cases, among which 9 cases were transmitted by homosexual sex. The first time of the cases to have homosexual behavior is range from 2010 to 2016, whose media number (P(25), P(75)) of partners was 6 (3.5, 8.5). Most of the cases come from Anhui Province and engaged in garment industry (5 cases), between which there were 8 cases used Blued software to seek for casual partners, 1 case seeking for casual partners in garden. Conclusion: With CRF07_BC and CRF01_AE predominantly circulating, HIV genetic diversity had been noticed in this area. The primary cluster was consisted of high proportion of locally new infections, and a specific population aggregation in limited place existed.


Assuntos
Síndrome de Imunodeficiência Adquirida/transmissão , Infecções por HIV/transmissão , HIV-1/genética , Síndrome de Imunodeficiência Adquirida/diagnóstico , China , Amplificação de Genes , Genótipo , Infecções por HIV/diagnóstico , HIV-1/isolamento & purificação , Humanos , Masculino , Epidemiologia Molecular , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(9): 925-928, 2019 Sep 06.
Artigo em Chinês | MEDLINE | ID: mdl-31474075

RESUMO

Objective: To identify the status and risky factors of anal sexual intention in casual sex behavior in Zhejiang province. Methods: Stratified cluster sampling was conducted among college students in 13 colleges in 11 cities between October to November, 2018. 482 students were enrolled who self-reported "heterosexuality "and" ever had casual sex behavior". A self-designed network questionnaire was complimented containing basic information, knowledge of HIV, sexual behavior. Chi-square test was used to compared the difference of anal sex intention between different characteristic. The multivariate logistic regression methods was used to analyze the influence factors. Results: Among 482 students, the age was (20±1.442) years old. And 87.3% (421) were male and 29.0% (140) were from other province. The rate of anal sex intention were 19.4% (94/482) in total, with the rates of 38.1% (24/63) and 14.4% (53/367) in students with sexual number more than 5 and less than 5 (P<0.001), separately. Compared with students searching casual sexual partner with non-internet access (17.0%, 16/201), students searching sexual partner with internet access had higher risk of anal sex practice (27.8%, 78/281) (P<0.001). The rate of anal sex practice among students reporting "ever had casual sex after drinking "and" never had casual sex after drinking" were 30.5% (64/210) and 9.4% (25/266) (P<0.001). The multivariate logistic regression results revealed that compared with students searching casual sexual partner with non-internet access and reporting "never had casual sex after drinking", subjects searching sexual partner with internet access(OR (95%CI)=2.65 (1.34-5.23)) and "ever had casual sex after drinking" OR (95%CI)=3.02 (1.65-5.33) were more likely had higher risk of anal sex practice. Conclusion: Heterosexual college students in Zhejiang Province tend to have anal intercourse with causal sexual partners. Searching for causal sexual partners on internet or mobile phone dating software and having temporary sexual behavior after drinking were correlated factors.


Assuntos
Comportamentos de Risco à Saúde , Heterossexualidade , Comportamento Sexual , Adolescente , Adulto , China , Feminino , Humanos , Intenção , Masculino , Comportamento Sexual/estatística & dados numéricos , Parceiros Sexuais , Estudantes/estatística & dados numéricos , Inquéritos e Questionários , Adulto Jovem
6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(2): 202-206, 2019 Feb 10.
Artigo em Chinês | MEDLINE | ID: mdl-30744273

RESUMO

Objective: To understand the epidemiological characteristics of one large HIV molecular transmission cluster in Jiaxing city, Zhejiang province, 2017 in order to select those people under high-risk and providing basis for programs on prevention. Methods: During 2017, newly diagnosed HIV/AIDS cases in this city were recruited. Plasma samples were collected from subjects, followed by RNA extraction, RT-PCR and nest-PCR for pol gene amplification, before being sequenced and aligned. Mega 6.0 software was used to construct phylogenetic tree, and Cytoscape 3.6.0 software was used to identify HIV molecular transmission clusters. Cases within the large transmission clusters were investigated, using a field-epidemiology-questionnaire. Data related to socio-demographics and previous sexual behaviors were collected and EpiData 3.0 and SPSS 20.0 software were used. Results: In the large transmission cluster with subtype identified as CRF07_BC, in Jiaxing, 2017, 26 cases of the total 30 cases were investigated. A total of 80.8% (21/26) could be identified as newly infected within the last two years and 30.8%(8/26) could be identified as newly infected within the last one year, including 22 cases infected locally. Among several infected cases who were at age 45 years or older, they admitted that they had experienced unprotected sexual contacts in local city for long time and having had more than 10 disclosed sexual contacts within the last two years at the local venues. Conclusions: This molecular cluster had been formed and scaled up quickly in recent two years, it has played an important role in promoting and scaling up the HIV transmission. Three cases identificed as high risk played an importantrde role in scaling up this cluster.


Assuntos
Genes pol , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , HIV-1/classificação , HIV-1/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , China/epidemiologia , Genótipo , Infecções por HIV/diagnóstico , Infecções por HIV/genética , HIV-1/isolamento & purificação , Humanos , Epidemiologia Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA Viral/sangue , Comportamento Sexual , Produtos do Gene pol do Vírus da Imunodeficiência Humana
7.
Zhonghua Nei Ke Za Zhi ; 58(2): 108-118, 2019 Feb 01.
Artigo em Chinês | MEDLINE | ID: mdl-30704197

RESUMO

To establish the experts consensus on the management of delirium in critically ill patients. A special committee was set up by 15 experts from the Chinese Critical Hypothermia-Sedation Therapy Study Group. Each statement was assessed based on the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) principle. Then the Delphi method was adopted by 36 experts to reassess all the statements. (1) Delirium is not only a mental change, but also a clinical syndrome with multiple pathophysiological changes. (2) Delirium is a form of disturbance of consciousness and a manifestation of abnormal brain function. (3) Pain is a common cause of delirium in critically ill patients. Analgesia can reduce the occurrence and development of delirium. (4) Anxiety or depression are important factors for delirium in critically ill patients. (5) The correlation between sedative and analgesic drugs and delirium is uncertain. (6) Pay attention to the relationship between delirium and withdrawal reactions. (7) Pay attention to the relationship between delirium and drug dependence/withdrawal reactions. (8) Sleep disruption can induce delirium. (9) We should be vigilant against potential risk factors for persistent or recurrent delirium. (10) Critically illness related delirium can affect the diagnosis and treatment of primary diseases, and can also be alleviated with the improvement of primary diseases. (11) Acute change of consciousness and attention deficit are necessary for delirium diagnosis. (12) The combined assessment of confusion assessment method for the intensive care unit and intensive care delirium screening checklist can improve the sensitivity of delirium, especially subclinical delirium. (13) Early identification and intervention of subclinical delirium can reduce its risk of clinical delirium. (14) Daily assessment is helpful for early detection of delirium. (15) Hopoactive delirium and mixed delirium are common and should be emphasized. (16) Delirium may be accompanied by changes in electroencephalogram. Bedside electroencephalogram monitoring should be used in the ICU if conditions warrant. (17) Pay attention to differential diagnosis of delirium and dementia/depression. (18) Pay attention to the role of rapid delirium screening method in delirium management. (19) Assessment of the severity of delirium is an essential part of the diagnosis of delirium. (20) The key to the management of delirium is etiological treatment. (21) Improving environmental factors and making patient comfort can help reduce delirium. (22) Early exercise can reduce the incidence of delirium and shorten the duration of delirium. (23) Communication with patients should be emphasized and strengthened. Family members participation can help reduce the incidence of delirium and promote the recovery of delirium. (24) Pay attention to the role of sleep management in the prevention and treatment of delirium. (25) Dexmedetomidine can shorten the duration of hyperactive delirium or prevent delirium. (26) When using antipsychotics to treat delirium, we should be alert to its effect on the heart rhythm. (27) Delirium management should pay attention to brain functional exercise. (28) Compared with non-critically illness related delirium, the relief of critically illness related delirium will not accomplished at one stroke. (29) Multiple management strategies such as ABCDEF, eCASH and ESCAPE are helpful to prevent and treat delirium and improve the prognosis of critically ill patients. (30) Shortening the duration of delirium can reduce the occurrence of long-term cognitive impairment. (31) Multidisciplinary cooperation and continuous quality improvement can improve delirium management. Consensus can promote delirium management in critically ill patients, optimize analgesia and sedation therapy, and even affect prognosis.


Assuntos
Estado Terminal , Delírio/terapia , Consenso , Humanos
8.
Beijing Da Xue Xue Bao Yi Xue Ban ; 51(1): 187-193, 2019 Feb 18.
Artigo em Chinês | MEDLINE | ID: mdl-30773566

RESUMO

OBJECTIVE: To retrospectively compare the effect of alternate levels miniplate and anchor fixation with the effect of all levels miniplate fixation in expansive open-door cervical laminoplasty (EOLP). METHODS: Patients with cervical spondylosis underwent EOLP between July 2015 and June 2016 were included in the study. There were 33 patients in the alternate group (alternate levels miniplate and anchor fixation group) and 34 patients in the miniplate group (all levels miniplate fixation group). Neurological function was evaluated with the Japanese Orthopedic Association (JOA) score and degree of pain was assessed with the visual analogue scale (VAS) score. Basic clinical and surgical data, complication rates and medical costs of the two groups were compared. In addition, radiological examinations were performed pre- and post-operatively and at the final follow-up. Relative imaging data such as anteroposterior diameter (APD), cervical curvature index (CCI) and open angle were collected and compared. RESULTS: (1) The mean follow-up time was 18.6 months in the alternate group and 18.9 months in the miniplate group. There were no significant differences in operation time, intraoperative blood loss, perioperative complication rates, post-operative hospital stays, VAS scores and neurological recovery rates preoperatively and at the final follow-up between the two groups. (2) Additionally, no obvious differences were observed about CCIs and APDs at the three follow-up time points between the two groups. Post-operative open angles at C4 and C6 in the alternate group were significantly smaller than those in the miniplate group. However, there were no significant differences in C3, C5 and C7 open angles between the two groups post-operatively. Notably, no significant differences were detected about the open angles at all levels between the two groups at the final follow-up. (3) When comparing radiologic data at different time points in each group, CCIs and open angles at each level had no significant differences, but APDs after surgery and at the final follow-up were significantly larger than pre-operative APDs. (4) Total costs in the alternate group were significantly lower than those in the miniplate group. CONCLUSION: The two surgical methods showed almost the same neurological recovery rates and complication rates. However, use of alternate levels miniplate and anchor fixation in EOLP can reduce medical expenses.


Assuntos
Laminoplastia , Placas Ósseas , Vértebras Cervicais , Humanos , Laminectomia , Estudos Retrospectivos , Resultado do Tratamento
9.
Osteoporos Int ; 30(4): 807-815, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30721331

RESUMO

After utilizing a large population-based claims database and the application of propensity score match approach to reduce the confounding effects, we found that the use of Chinese herbal medicines (CHMs) was related to the lower risk of sequent osteoporotic fracture by 27% among the individuals with osteoporosis. The predominant effect was observed in those receiving CHMs for more than two years. INTRODUCTION: Osteoporosis (OS) is a highly disabling condition that can lead to fragility fracture, thus posing greater burdens of functional limitations for the affected individuals. It is unclear if the use of Chinese herbal medicines (CHMs) could reduce the risk of fracture due to OS. This study aimed to investigate the association of CHMs and the subsequent osteoporotic fracture risk among OS patients. METHODS: This longitudinal cohort study used the Taiwanese National Health Insurance Research Database to identify 250,699 newly diagnosed OS patients aged 20 years or older between 1998 and 2010. We recruited 103,325 CHM users following the onset of OS (CHM users) and randomly selected 103,325 subjects without CHM usage as controls (non-CHM users) by propensity score matching according to the demographic characteristics and comorbidities at enrollment. All enrollees were followed until the end of 2012 to record the incidence of osteoporotic fracture. We applied the Cox proportional hazard regression model to compute the hazard ratio (HR) of the risk of osteoporotic fracture. RESULTS: During the 15-year follow-up period, 7208 CHM users and 11,453 non-CHM users sustained osteoporotic fracture, with an incidence rate of 9.26 and 12.96, respectively, per 1000 person-years. We found that CHM users had a significantly reduced risk of osteoporotic fracture compared to non-CHM users (adjusted HR 0.73; 95% confidence interval [CI] = 0.70-0.75). Those treated with CHMs for longer than 730 days had a lower fracture risk by 54%. Some commonly used CHMs, such as Yan hu suo (Rhizoma Corydalis), Huang Qin (Scutellaria Baicale), Jie Geng (Platycodon grandifloras), Xiang Fu (Cyperus rotundus), Hai Piao Xiao (Cuttlebone Sepium), Jia-Wei-Xiao-Yao-San, Ge-Gen-Tang, Shao-Yao-Gan-Cao-Tang, and Du-Huo-Ji-Sheng-Tang, are related to the lower risk of fracture. CONCLUSIONS: The use of CHMs was associated with lower risk of osteoporotic fracture for OS patients, suggesting that it could be integrated into conventional therapy to prevent subsequent bone fracture.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/prevenção & controle , Adulto , Idoso , Estudos de Casos e Controles , Bases de Dados Factuais , Uso de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Incidência , Estimativa de Kaplan-Meier , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Osteoporose/epidemiologia , Fraturas por Osteoporose/epidemiologia , Medição de Risco/métodos , Fatores Socioeconômicos , Taiwan/epidemiologia , Adulto Jovem
10.
J Mech Behav Biomed Mater ; 92: 172-178, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30710832

RESUMO

A better understanding of the adhesive behavior of human facial skin is important for dermatological or cosmetic applications. For their in vivo experimental characterization and analysis, the indentation test is an effective and widely used method. In this study, our independently developed transparent indenter and curved surface optical imaging technique are improved, by which the contact area of facial skin can be in vivo and in situ obtained during an indentation test. Thanks to the modified indentation technique, the real contact radii of human facial skin under different conditions (normal, as-moistened, moistened after 30 min) are obtained, and their adhesive behavior is studied. Moreover, we modify the classical elastic adhesion theory (JKR theory) based on the Neo-hookean model considering the fact that the hyperelastic model is usually more appropriate for skin research. It is evidenced that the adhesion properties highly influence the contact area as well as the adhesive force/energy, and our modified hyperelastic adhesion theoretical model shows a better agreement with the experimental values of contact radius under each condition.

11.
QJM ; 112(5): 343-350, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30690642

RESUMO

BACKGROUND: Brugada syndrome (BrS) is a heritable sudden cardiac death (SCD) disease with male predominance. Information on gender difference of BrS remains scarce. AIM: To investigate the gender difference of BrS in Han Chinese. DESIGN: We consecutively enrolled 169 BrS patients (153 males and 16 females) from Han Chinese in Taiwan from 1998 to 2017. METHODS: Clinical characteristics, electrocardiographic parameters and SCN5A mutation status were compared between genders. RESULTS: The percentage of family history of SCD in females was slightly higher (31.3% vs. 15%, P = 0.15). Females exhibited longer QTc (457.8 ± 33.0 vs. 429.5 ± 42.1 ms, P < 0.01). Regarding cumulative event occurrence by age, Mantel-Cox test showed females had earlier age of onset of first cardiac events (SCD or syncope) than males (P = 0.049), which was mainly attributed to syncope (P < 0.01). Males with SCD exhibited longer QRS duration (114.2 ± 26.8 vs. 104.8 ± 15.3 ms, P = 0.02) and QTc (442.5 ± 57.4 vs. 422.9 ± 28.8 ms, P = 0.02). Males with syncope exhibited longer PR interval (181.2 ± 33.7 vs. 165.7 ± 27.1 ms, P = 0.01), whereas females with SCD or syncope had a trend towards slower heart rates (69.1 ± 9.6 vs. 82.2 ± 16.3 bpm, P = 0.10) than female with no or mild symptoms. There was no difference in the percentage of SCN5A mutation between genders. CONCLUSION: Gender difference is present in BrS. Females have longer QTc and suffer from syncope earlier than males. Risk of SCD in males is associated with boarder QRS complex and longer QTc, whereas risk of syncope is associated with longer PR interval in males and slower heart rate in females.


Assuntos
Síndrome de Brugada/genética , Morte Súbita Cardíaca/epidemiologia , Síndrome do QT Longo/epidemiologia , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Fatores Sexuais , Síncope/etiologia , Adulto , Síndrome de Brugada/complicações , Síndrome de Brugada/fisiopatologia , Morte Súbita Cardíaca/etiologia , Eletrocardiografia , Feminino , Humanos , Síndrome do QT Longo/etiologia , Masculino , Pessoa de Meia-Idade , Mutação , Sistema de Registros , Medição de Risco , Distribuição por Sexo , Síncope/epidemiologia , Taiwan/epidemiologia
12.
J Phys Condens Matter ; 31(14): 145701, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30634175

RESUMO

The recent observation of mechanical switching of ferroelectric polarization has placed the mechanical manipulation of ferroelectrics on an equal footing with the conventional electrical manipulation. However, discussions on the exact switching mechanisms due to mechanical loads are ongoing for the complexity in experimental situations. In this work, based on continuum mechanical and thermodynamic modeling and simulation, we analyze the mechanisms of tip-force induced switching in ferroelectric thin films. The roles of depolarization, shear strain and flexoelectricity in mechanical switching, both in normal and sliding loading modes, are separated out and the switching characteristics are analyzed. The depolarization field in the film is demonstrated to enable bidirectional switching. The coupling between shear strain and polarization components is shown to be important in the sliding loading mode. A great influence of flexoelectricity-modified polarization boundary condition on the switching process is revealed. The previous speculation that the switching process experiences an intermediate paraelectric phase is proved. The regulation of loading force, misfit strain, temperature and film thickness on the switching are further given for each mechanism. Taking all of the three mechanisms into account, we present the phase diagrams of mechanical switching for films in an initial upward or downward polarization state. The revealed characteristics of various switching mechanisms should provide useful guidelines for their verification in experiments, and the tunability of the switching by various influencing factors is instructive for the design and optimization of ferroelectric devices via mechanical engineering.

14.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(12): 1601-1605, 2019 Dec 10.
Artigo em Chinês | MEDLINE | ID: mdl-32062923

RESUMO

Objective: To understand the confidence-related factors of refusing unprotected sex behavior among college students in Zhejiang province. Methods: Stratified cluster random sampling method was conducted among college students from 13 colleges and universities in Zhejiang province, from October to November, 2018. A total of 3 718 students who self-reported "ever having had sexual contacts" were enrolled. Chi-square test was used to compare the confidence of rejecting unprotected sex under different demographic characteristics, sexual attitude/behaviors and different intervention approaches. Multivariate logistic regression model was used to analyze the related factors. Results: A total of 3 718 college students were involved in this study with average age as (20.17±1.38) years old and 70.5% (2 620/3 718) were male. The proportions of having confidence to refuse unprotected sex behavior were 74.9% (1 963/2 620) of male and 77.9% (896/1 098) of female students, respectively. According to the results from multivariate logistic regression analysis, factors that related to the confidence of refusing unprotected sex behavior in male students would include, did not accept casual sex behavior (compared with accepted students, OR=2.247, 95%CI: 1.828-2.762), did not accept homosexual behavior (compared with accepted students, OR=1.810, 95%CI: 1.302- 2.516), having casual sex behavior in the past one year (compared with having no sex behavior, OR=1.345, 95%CI: 1.051-1.721), aware of the availability of HIV self-test reagents service in college (compared with did not knew, OR=1.381, 95%CI: 1.011-1.887), having taken the HIV infection risk self-assessment in college (compared with did not take, OR=1.707, 95%CI: 1.374-2.121). In female students, the factors would include: being urban resident (compared with rural residence, OR=1.816, 95%CI: 1.225-2.693), 21 years old or above (compared with 20 years old or below, OR=1.469, 95%CI: 1.075-2.007), having taken the HIV infection risk self-assessment in college (compared with did not take, OR=1.597, 95%CI: 1.093-2.333), etc. Conclusions: Both male and female college students had higher confidence in refusing unprotected sex behavior. For male students, refusing casual or homosexual contacts, having casual sex in the recent year, knowing HIV self-test reagents service and having had HIV-related risk self-assessment in college as related factors. However, for female students; city residence, 21 years old and above, and having a HIV infection risk self- assessment in college appeared as related factors. Sexual health education should be strengthened to reduce unprotective sex behavior and to promote HIV infection risk self-assessment among the college students.

15.
Eur Rev Med Pharmacol Sci ; 22(22): 7646-7652, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30536306

RESUMO

OBJECTIVE: Increasing evidence has revealed that microRNAs (miRNAs) act as key players in the regulation of tumor growth and metastasis in epithelial ovarian cancer (EOC). However, the clinical role and functional effects of miR-1294 in EOC remain unknown. PATIENTS AND METHODS: We examined the expression of miR-1294 in 69 cases of EOC tissues and cell lines by quantitative Real-time polymerase chain reaction (qRT-PCR). The associations of miR-1294 expression with clinicopathologic features and overall survival of EOC patients were analyzed. Biological functional effects of miR-1294 expression on cell growth were analyzed using Cell Counting Kit-8 (CCK8) assays and flow cytometry assays in vitro. RESULTS: In the present study, we identified that miR-1294 expression was lower in 76 specimens of EOC compared to adjacent normal tissues. Lower miR-1294 expression was related to FIGO stage, lymph node metastasis and shorter overall survival rate in EOC patients. Multivariate Cox analysis demonstrated that miR-1294 expression was an independent prognostic indicator of EOC patients. Gain function assays showed that miR-1294 overexpression inhibited cell proliferation and cell cycle progression in EOC. CONCLUSIONS: Our results indicated that miR-1294 acted as a prognostic biomarker and potential target of EOC treatment.


Assuntos
Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/patologia , MicroRNAs/genética , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Adulto , Idoso , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática/genética , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida
16.
Zhonghua Er Ke Za Zhi ; 56(9): 657-661, 2018 Sep 02.
Artigo em Chinês | MEDLINE | ID: mdl-30180403

RESUMO

Objective: To summarize the characteristics of cuffed-tunneled catheters insertion and investigate the values of cuffed-tunneled catheters in pediatric patients. Methods: Between March 2015 and July 2017, all the pediatric patients who received maintenance hemodialysis at least 3 consecutive months in our center were included. Sixteen cuffed-tunneled hemodialysis catheters were inserted in patients for long-term hemodialysis access. The clinical manifestations and complications were retrospectively reviewed. Results: Fifteen pediatric patients with end stage ranal disease (ESRD) were included in this study and they received 16 cuffed-tunneled catheters for long-term vascular access, including 10 males and 5 females; median age at start of catheter insertion was 11.5 (4.2-14.5) years. Body weight was (27.8±8.0)kg (16.0-39.4 kg) . The size and the length of the catheters were based on the height of patients as follows: 28 cm for (115.6±10.6) cm (102.0-130.0 cm) ,36 cm for (148.6±9.9)cm (140.0-167.0 cm) . Cuffed-tunneled catheters outcome: 10 cuffed-tunneled catheters were still functional at the end of the study; 5 catheters were removed after successful kidney transplantation. Catheter failure occurred in 1 out of 16 cuffed-tunneled catheters due to catheter-related infections. The median catheter survival time was 11.9 months (range 3.5-21.3 months). Complications of cuffed-tunneled catheters: Catheter placements operation was successful in 15 cases using ultrasound guidance. No serious complications were observed in any patients receiving catheter inserting operation. The overall rate of catheter-related infections and thrombosis/malposition was 6.3% and 18.7%, respectively. Conclusions: Ultrasound guidance is suggested in pediatric patients during the catheters insertion. The size and the length of the catheters should be based on the height of patients. Cuffed-tunneled hemodialysis catheters could be effectively used for maintenance of hemodialysis vascular access for pediatric patients with ESRD.


Assuntos
Cateterismo Venoso Central , Cateteres de Demora , Diálise Renal , Adolescente , Infecções Relacionadas a Cateter/etiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Retrospectivos
17.
Zhonghua Nei Ke Za Zhi ; 57(6): 397-417, 2018 Jun 01.
Artigo em Chinês | MEDLINE | ID: mdl-29925125

RESUMO

Critical ultrasonography(CUS) is different from the traditional diagnostic ultrasound, the examiner and interpreter of the image are critical care medicine physicians. The core content of CUS is to evaluate the pathophysiological changes of organs and systems and etiology changes. With the idea of critical care medicine as the soul, it can integrate the above information and clinical information, bedside real-time diagnosis and titration treatment, and evaluate the therapeutic effect so as to improve the outcome. CUS is a traditional technique which is applied as a new application method. The consensus of experts on critical ultrasonography in China released in 2016 put forward consensus suggestions on the concept, implementation and application of CUS. It should be further emphasized that the accurate and objective assessment and implementation of CUS requires the standardization of ultrasound image acquisition and the need to establish a CUS procedure. At the same time, the standardized training for CUS accepted by critical care medicine physicians requires the application of technical specifications, and the establishment of technical specifications is the basis for the quality control and continuous improvement of CUS. Chinese Critical Ultrasound Study Group and Critical Hemodynamic Therapy Collabration Group, based on the rich experience of clinical practice in critical care and research, combined with the essence of CUS, to learn the traditional ultrasonic essence, established the clinical application technical specifications of CUS, including in five parts: basic view and relevant indicators to obtain in CUS; basic norms for viscera organ assessment and special assessment; standardized processes and systematic inspection programs; examples of CUS applications; CUS training and the application of qualification certification. The establishment of applied technology standard is helpful for standardized training and clinical correct implementation. It is helpful for clinical evaluation and correct guidance treatment, and is also helpful for quality control and continuous improvement of CUS application.


Assuntos
Cuidados Críticos/métodos , Hemodinâmica , Médicos , Ultrassonografia/métodos , China , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Phys Chem Chem Phys ; 20(21): 14339-14347, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29683159

RESUMO

As an important strongly correlated electron material, VO2 undergoes a metal-insulator transition (MIT) accompanied by a huge change of several orders of magnitude in conductance and transmittance. The MIT behavior can be controlled by low-dimensional structures (LDSs) and the interaction between LDSs and substrates. Consequently, fabricating the LDSs and understanding the phase transition behaviors have great significance for the investigation of fundamental properties and applications. Using the pulsed laser deposition technique, we fabricate abundant LDSs (i.e., from zero-dimensional nanodots, one-dimensional nanowires, nanobelts and nanorods to two-dimensional nanoplatelets and ultra-thin films, and zero-/one-/two-dimensional mixed structures), and investigate the controllability of each deposition factor on the growth of the LDSs. TEM results confirm the high crystallinity of the as-synthesized LDSs. AFM results and ab initio calculations demonstrate the great influence of substrates on the growth orientation of the LDSs. More importantly, we systematically investigate the phase transition characteristics of the LDSs by temperature-dependent Raman spectroscopy and XRD. The results clearly reveal the structural dependence of the phase transition features due to the delicate effects of substrates and structures. Our technique provides a rapid, controllable and easy method for fabricating VO2 LDSs, which can lead to a deeper understanding of the electrical, optical, and magnetic properties and potential applications of VO2.

20.
Eur Rev Med Pharmacol Sci ; 22(1): 101-109, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29364476

RESUMO

OBJECTIVE: To investigate the role of microRNA-155 (miR-155) in the potential invasion of colon cancer cell and the underlying mechanism. PATIENTS AND METHODS: The expression level of miR-155 in colon cancer and adjacent normal tissues was detected by Real-time quantitative polymerase chain reaction (RT-PCR). miR-155 mimics (miR-155), or siRNA against ß-catenin (ß-catenin siRNA), was transfected into human colon cancer cell line SW-480 using Lipofectamine 2000, respectively. RT-PCR was used to measure the expression levels of miR-155 and ß-catenin mRNA, and ß-catenin protein expression level was detected by Western blot. The in-vitro cell invasion abilities were determined by transwell invasion assays after up-regulating miR-155 or knocking down of ß-catenin. RESULTS: MiR-155 directly regulates ß-catenin at the transcriptional level, and promotes the invasion potential of colon cancer cell, at least partly through the upregulation of ß-catenin. CONCLUSIONS: The findings of this study suggest that miR-155 and ß-catenin may have a unique potential as a novel biomarker candidate for diagnosis and treatment of tumor metastasis.


Assuntos
MicroRNAs/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Antagomirs/metabolismo , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Humanos , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Via de Sinalização Wnt , beta Catenina/antagonistas & inibidores , beta Catenina/genética
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