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1.
Beijing Da Xue Xue Bao Yi Xue Ban ; 56(3): 487-494, 2024 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-38864135

RESUMO

OBJECTIVE: To unveil the pathological changes associated with demyelination in schizophrenia (SZ) and its consequential impact on interstitial fluid (ISF) drainage, and to investigate the therapeutic efficacy of ursolic acid (UA) in treating demyelination and the ensuing abnormalities in ISF drainage in SZ. METHODS: Female C57BL/6J mice, aged 6-8 weeks and weighing (20±2) g, were randomly divided into three groups: control, SZ model, and UA treatment. The control group received intraperitoneal injection (ip) of physiological saline and intragastric administration (ig) of 1% carboxymethylcellulose sodium (CMC-Na). The SZ model group was subjected to ip injection of 2 mg/kg dizocilpine maleate (MK-801) and ig administration of 1% CMC-Na. The UA treatment group underwent ig administration of 25 mg/kg UA and ip injection of 2 mg/kg MK-801. The treatment group received UA pretreatment via ig administration for one week, followed by a two-week drug intervention for all the three groups. Behavioral assessments, including the open field test and prepulse inhibition experiment, were conducted post-modeling. Subsequently, changes in the ISF partition drainage were investigated through fluorescent tracer injection into specific brain regions. Immunofluorescence analysis was employed to examine alterations in aquaporin 4 (AQP4) polarity distribution in the brain and changes in protein expression. Myelin reflex imaging using Laser Scanning Confocal Microscopy (LSCM) was utilized to study modifications in myelin within the mouse brain. Quantitative data underwent one-way ANOVA, followed by TukeyHSD for post hoc pairwise comparisons between the groups. RESULTS: The open field test revealed a significantly longer total distance [(7 949.39±1 140.55) cm vs. (2 831.01±1 212.72) cm, P < 0.001] and increased central area duration [(88.43±22.06) s vs. (56.85±18.58) s, P=0.011] for the SZ model group compared with the controls. The UA treatment group exhibited signifi-cantly reduced total distance [(2 415.80±646.95) cm vs. (7 949.39±1 140.55) cm, P < 0.001] and increased central area duration [(54.78±11.66) s vs. (88.43±22.06) s, P=0.007] compared with the model group. Prepulse inhibition test results demonstrated a markedly lower inhibition rate of the startle reflex in the model group relative to the controls (P < 0.001 for both), with the treatment group displaying significant improvement (P < 0.001 for both). Myelin sheath analysis indicated significant demyelination in the model group, while UA treatment reversed this effect. Fluorescence tracing exhibited a significantly larger tracer diffusion area towards the rostral cortex and reflux area towards the caudal thalamus in the model group relative to the controls [(13.93±3.35) mm2 vs. (2.79±0.94) mm2, P < 0.001 for diffusion area; (2.48±0.38) mm2 vs. (0.05±0.12) mm2, P < 0.001 for reflux area], with significant impairment of drainage in brain regions. The treatment group demonstrated significantly reduced tracer diffusion and reflux areas [(7.93±2.48) mm2 vs. (13.93±3.35) mm2, P < 0.001 for diffusion area; (0.50±0.30) mm2 vs. (2.48±0.38) mm2, P < 0.001 for reflux area]. Immunofluorescence staining revealed disrupted AQP4 polarity distribution and reduced AQP4 protein expression in the model group compared with the controls [(3 663.88±733.77) µm2 vs. (13 354.92±4 054.05) µm2, P < 0.001]. The treatment group exhibited restored AQP4 polarity distribution and elevated AQP4 protein expression [(11 104.68±3 200.04) µm2 vs. (3 663.88±733.77) µm2, P < 0.001]. CONCLUSION: UA intervention ameliorates behavioral performance in SZ mice, Thus alleviating hyperactivity and anxiety symptoms and restoring sensorimotor gating function. The underlying mechanism may involve the improvement of demyelination and ISF drainage dysregulation in SZ mice.


Assuntos
Doenças Desmielinizantes , Modelos Animais de Doenças , Líquido Extracelular , Camundongos Endogâmicos C57BL , Esquizofrenia , Triterpenos , Ácido Ursólico , Animais , Camundongos , Triterpenos/uso terapêutico , Triterpenos/farmacologia , Esquizofrenia/tratamento farmacológico , Feminino , Doenças Desmielinizantes/tratamento farmacológico , Líquido Extracelular/efeitos dos fármacos , Líquido Extracelular/metabolismo , Maleato de Dizocilpina , Aquaporina 4/metabolismo
2.
Sensors (Basel) ; 21(4)2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33562177

RESUMO

Whole-body vibration (WBV) is commonly applied in exercise and rehabilitation and its safety issues have been a major concern. Vibration measured using accelerometers can be used to further analyze the vibration transmissibility. Optimal bending angles and rating of perceived exertion (RPE) evaluations have not been sufficiently explored to mitigate the adverse effect. Therefore, the aims of this study were to investigate the effect of various knee flexion angles on the transmissibility to the head and knee, the RPE during WBV exposure, and the link between the transmissibility to the head and the RPE. Sixteen participants randomly performed static squats with knee flexion angles of 90, 110, 130, and 150 degrees on a WBV platform. Three accelerometers were fixed on the head, knee, and center of the vibration platform to provide data of platform-to-head and platform-to-knee transmissibilities. The results showed that the flexion angle of 110 degrees induced the lowest platform-to-head transmissibility and the lowest RPE (p < 0.01). A positive correlation between RPE and the platform-to-head transmissibility was observed. This study concluded that a knee flexion of about 110 degrees is most appropriate for reducing vibration transmissibility. The reported RPE could be used to reflect the vibration impact to the head.


Assuntos
Esforço Físico , Vibração , Exercício Físico , Humanos , Músculo Esquelético , Postura , Amplitude de Movimento Articular
3.
Chin J Traumatol ; 23(5): 258-264, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32771244

RESUMO

OBJECTIVE: Fragment injury is a type of blast injury that is becoming more and more common in military campaigns and terrorist attacks. Numerical simulation methods investigating the formation of natural fragments and injuries to biological targets are expected to be developed. METHODS: A cylindrical warhead model was established and the formation process of natural fragments was simulated using the approach of tied nodes with failure through the explicit finite element (FE) software of LS-DYNA. The interaction between the detonation product and the warhead shell was simulated using the fluid-structure interaction algorithm. A method to simulate the injury of natural fragments to a biological target was presented by transforming Lagrange elements into smooth particle hydrodynamics (SPH) particles after the natural fragments were successfully formed. A computational model of the human thorax was established to simulate the injury induced by natural fragments by the node-to-surface contact algorithm with erosion. RESULTS: The discontinuous velocities of the warhead shell at different locations resulted in the formation of natural fragments with different sizes. The velocities of natural fragments increased rapidly at the initial stage and slowly after the warhead shell fractured. The initial velocities of natural fragments at the central part of the warhead shell were the largest, whereas those at both ends of the warhead shell were the smallest. The natural fragments resulted in bullet holes that were of the same shape as that of the fragments but slightly larger in size than the fragments in the human thorax after they penetrated through. Stress waves propagated in the ribs and enhanced the injury to soft tissues; additionally, ballistic pressure waves ahead of the natural fragments were also an injury factor to the soft tissues. CONCLUSION: The proposed method is effective in simulating the formation of natural fragments and their injury to biological targets. Moreover, this method will be beneficial for simulating the combined injuries of natural fragments and shock waves to biological targets.


Assuntos
Traumatismos por Explosões/etiologia , Simulação por Computador , Modelos Anatômicos , Traumatismos Torácicos/etiologia , Traumatismos por Explosões/complicações , Análise de Elementos Finitos , Ondas de Choque de Alta Energia/efeitos adversos , Humanos
4.
J Exerc Sci Fit ; 18(3): 142-147, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32514277

RESUMO

BACKGROUND: Tai-Chi benefits older adults by enhancing balance control and increasing the muscle strength of the lower limbs. However, a complete set of traditional Tai-Chi exercises is sometimes too difficult for beginners. We investigated whether practicing augmented reality-assisted training with selected Tai-Chi movements tailored to the practitioner's ability (selected Tai-Chi, or sTC) is as effective as performing a complete set of Tai-Chi sequences (complete traditional Tai-Chi, or tTC). METHODS: In this prospective randomized trial carried out in the Beitou District of Taipei City, Taiwan, community-dwelling adults aged ≥65 and without any debilitating diseases (n = 28) were included. Participants were randomly assigned to the sTC group (n = 14) or the tTC group (n = 14). Participants in the sTC group practiced selected Tai-Chi movements using the augmented reality Tai-Chi training system. Participants of the tTC group were asked to complete the 24-form Yang-style Tai-Chi following the instructions of Tai-Chi masters. Each training session lasted 30 min, with 3 sessions per week for 8 weeks. Pre- and post-intervention evaluations included functional balance tests, comprising the Berg Balance Scale (BBS), Timed Up and Go test (TUG), and Functional Reach Test (FRT), as well as muscle strength measurements of the lower extremities. RESULTS: Pre-intervention evaluations showed significant differences in FRT (p = 0.034) and left hip abductor muscle strength (p = 0.046) between the sTC and tTC groups. After 8 weeks of training, the BBS, TUG, and FRT scores in the sTC group showed significant improvement overall. Although all three functional balance test scores improved in the tTC group, only the improvement in BBS was statistically significant (p = 0.001). After 8 weeks, all muscle strength measurements increased by an average of 3.1 ± 1.0 kgw in the sTC group and 1.6 ± 0.8 kgw in the tTC group. CONCLUSIONS: The augmented reality-assisted training with selected Tai-Chi movements, designed based on objective measurements of the practitioner's capability, improved balance control and muscle strength of lower limbs at least as effectively as the complete sequence of traditional Tai-Chi exercises. TRIAL REGISTRATION: This study was approved by the Institutional Review Board of National Yang-Ming University (IRB number: 1000087). Written informed consent was obtained from all participants.

5.
Chem Res Toxicol ; 32(11): 2204-2213, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31617706

RESUMO

Cantharidin is the major bioactive compound extracted from the blister beetle, a traditional Chinese medicine, and has been proved to be a natural component with widely antitumor activity. However, clinical application of cantharidin is relatively restricted due to its potential toxic effects, especially hepatotoxicity. Although cantharidin-induced liver injury has been reported, the underlying molecular mechanisms remain unclear. In the present study, an UPLC-Q-TOF/MS based metabolomics approach combined with blood biochemical analysis, histopathological examination, and cell apoptosis assay were used to investigate the mechanisms of cantharidin-induced hepatotoxicity. A total of 54 significantly changed metabolites and 14 disturbed metabolic pathways were identified in the cantharidin exposed groups. Among them, four metabolites (oxidized glutathione, glutathione, 3-sulfinoalanine, and deoxycholic acid 3-glucuronide) were selected based on their high impact value and potential biological function in the process of liver injury post cantharidin treatment. Our study provides a deeper understanding of the mechanisms of cantharidin-induced hepatotoxicity and may contribute to reduce the liver injury and gain more effective and safe clinical use of cantharidin. In addition, our results also demonstrated that cantharidin could impair multiple biological processes in liver, and future studies will be necessary to reveal the detailed molecular mechanisms of cantharidin-induced hepatotoxicity.


Assuntos
Antineoplásicos/toxicidade , Cantaridina/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Doença Hepática Induzida por Substâncias e Drogas/patologia , Cromatografia Líquida de Alta Pressão , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Espectrometria de Massas , Metabolômica/métodos , Camundongos
6.
Int J Legal Med ; 133(2): 429-431, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29557504

RESUMO

In the present study, population data of 19 autosomal STR loci included in the Goldeneye™ DNA ID System 20A in 653 Li individuals was obtained and population genetic relationships among 13 populations were investigated. MDS and phylogenetic analysis suggested that the Hainan Li population kept a close genetic relationship with the Chinese Han populations, especially for Southern Han populations (Guangdong Han, Sichuan Han, and Hunan Han). Our results indicated that the 19 autosomal STRs are highly discriminative and polymorphic in the Hainan Li population suitable for personal forensic identification and paternity testing.


Assuntos
Etnicidade/genética , Genética Populacional , Repetições de Microssatélites , China , Impressões Digitais de DNA , Feminino , Frequência do Gene , Humanos , Masculino , Reação em Cadeia da Polimerase , Polimorfismo Genético
7.
Bioinformatics ; 33(1): 35-41, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27531102

RESUMO

MOTIVATION: Coexisting in a DNA system, meiosis and recombination are two indispensible aspects for cell reproduction and growth. With the avalanche of genome sequences emerging in the post-genomic age, it is an urgent challenge to acquire the information of DNA recombination spots because it can timely provide very useful insights into the mechanism of meiotic recombination and the process of genome evolution. RESULTS: To address such a challenge, we have developed a predictor, called IRSPOT-EL: , by fusing different modes of pseudo K-tuple nucleotide composition and mode of dinucleotide-based auto-cross covariance into an ensemble classifier of clustering approach. Five-fold cross tests on a widely used benchmark dataset have indicated that the new predictor remarkably outperforms its existing counterparts. Particularly, far beyond their reach, the new predictor can be easily used to conduct the genome-wide analysis and the results obtained are quite consistent with the experimental map. AVAILABILITY AND IMPLEMENTATION: For the convenience of most experimental scientists, a user-friendly web-server for iRSpot-EL has been established at http://bioinformatics.hitsz.edu.cn/iRSpot-EL/, by which users can easily obtain their desired results without the need to go through the complicated mathematical equations involved. CONTACT: bliu@gordonlifescience.org or bliu@insun.hit.edu.cnSupplementary information: Supplementary data are available at Bioinformatics online.


Assuntos
Cromossomos Fúngicos , Meiose , Recombinação Genética , Análise de Sequência de DNA/métodos , Software , Genômica/métodos , Leveduras/genética
8.
Bioinformatics ; 32(16): 2411-8, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27153623

RESUMO

MOTIVATION: Regulatory DNA elements are associated with DNase I hypersensitive sites (DHSs). Accordingly, identification of DHSs will provide useful insights for in-depth investigation into the function of noncoding genomic regions. RESULTS: In this study, using the strategy of ensemble learning framework, we proposed a new predictor called iDHS-EL for identifying the location of DHS in human genome. It was formed by fusing three individual Random Forest (RF) classifiers into an ensemble predictor. The three RF operators were respectively based on the three special modes of the general pseudo nucleotide composition (PseKNC): (i) kmer, (ii) reverse complement kmer and (iii) pseudo dinucleotide composition. It has been demonstrated that the new predictor remarkably outperforms the relevant state-of-the-art methods in both accuracy and stability. AVAILABILITY AND IMPLEMENTATION: For the convenience of most experimental scientists, a web server for iDHS-EL is established at http://bioinformatics.hitsz.edu.cn/iDHS-EL, which is the first web-server predictor ever established for identifying DHSs, and by which users can easily get their desired results without the need to go through the mathematical details. We anticipate that IDHS-EL: will become a very useful high throughput tool for genome analysis. CONTACT: bliu@gordonlifescience.org or bliu@insun.hit.edu.cn SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Algoritmos , Desoxirribonuclease I , Nucleotídeos , DNA , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Análise de Sequência de DNA
9.
Bioinformatics ; 32(3): 362-9, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26476782

RESUMO

MOTIVATION: Enhancers are of short regulatory DNA elements. They can be bound with proteins (activators) to activate transcription of a gene, and hence play a critical role in promoting gene transcription in eukaryotes. With the avalanche of DNA sequences generated in the post-genomic age, it is a challenging task to develop computational methods for timely identifying enhancers from extremely complicated DNA sequences. Although some efforts have been made in this regard, they were limited at only identifying whether a query DNA element being of an enhancer or not. According to the distinct levels of biological activities and regulatory effects on target genes, however, enhancers should be further classified into strong and weak ones in strength. RESULTS: In view of this, a two-layer predictor called ' IENHANCER-2L: ' was proposed by formulating DNA elements with the 'pseudo k-tuple nucleotide composition', into which the six DNA local parameters were incorporated. To the best of our knowledge, it is the first computational predictor ever established for identifying not only enhancers, but also their strength. Rigorous cross-validation tests have indicated that IENHANCER-2L: holds very high potential to become a useful tool for genome analysis. AVAILABILITY AND IMPLEMENTATION: For the convenience of most experimental scientists, a web server for the two-layer predictor was established at http://bioinformatics.hitsz.edu.cn/iEnhancer-2L/, by which users can easily get their desired results without the need to go through the mathematical details. CONTACT: bliu@gordonlifescience.org, bliu@insun.hit.edu.cn, xlan@stanford.edu, kcchou@gordonlifescience.org SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Elementos Facilitadores Genéticos , Análise de Sequência de DNA/métodos , Software , DNA/química , Genômica/métodos , Nucleotídeos/análise
10.
Prev Sci ; 16(2): 301-12, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24504568

RESUMO

We aimed to investigate the associations between three smoking-related constructs (pros and cons of smoking, temptation to smoke, and self-efficacy of resisting smoking) and stage of change (precontemplation, contemplation, preparation, and action) based on the transtheoretical model among smokers attending a community-based screening program. We also assessed their effects on long-term all-cause mortality. A prospective cohort study, with an average of 7 years of follow-up, was conducted by enrolling 454 male smoking screenees. The comparisons of the mean score of each variable pertaining to three smoking-related constructs across four stages of smoking cessation were assessed by analysis of variance. The impacts of both smoking-related constructs and smoking cessation stage measured at baseline on 7-year mortality were assessed by using proportional hazards regression model. The differences in the mean scores of pros and cons of smoking, temptation to smoke, and self-efficacy of resisting smoking across four stages of smoking cessation were statistically significant (P < 0.01). The precontemplation group and the contemplation group as opposed to the action group increased the risk for all-cause mortality, but the size of effect was not statistically significant (P = 0.39) when age, duration of smoking, and three smoking- related constructs were controlled. Those with a lower social aspect of self-efficacy were approximately threefold [adjusted hazard ratio = 3.22 (95 % CI 1.26-8.21)] risk for all-cause death compared with those with a higher one. Three smoking-related constructs were highly associated with smoking cessation stage, and low self-efficacy was independently predictive of long-term mortality among male smokers attending a community-based screening program.


Assuntos
Tomada de Decisões , Abandono do Hábito de Fumar/psicologia , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , Estudos Prospectivos , Taiwan
11.
J Sports Sci Med ; 12(1): 19-26, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24149721

RESUMO

The aim of this study was to determine whether performing Tai Chi Chuan on a customized vibration platform could enhance balance control and lower extremity muscle power more efficiently than Tai Chi Chuan alone in an untrained young population. Forty-eight healthy young adults were randomly assigned to the following three groups: a Tai Chi Chuan combined with vibration training group (TCV), a Tai Chi Chuan group (TCC) or a control group. The TCV group underwent 30 minutes of a reformed Tai Chi Chuan program on a customized vibration platform (32 Hz, 1 mm) three times a week for eight weeks, whereas the TCC group was trained without vibration stimuli. A force platform was used to measure the moving area of a static single leg stance and the heights of two consecutive countermovement jumps. The activation of the knee extensor and flexor was also measured synchronously by surface electromyography in all tests. The results showed that the moving area in the TCV group was significantly decreased by 15.3%. The second jump height in the TCV group was significantly increased by 8.14%, and the activation of the knee extensor/flexor was significantly decreased in the first jump. In conclusion, Tai Chi Chuan combined with vibration training can more efficiently improve balance control, and the positive training effect on the lower extremity muscle power induced by vibration stimuli still remains significant because there is no cross-interaction between the two different types of training methods. Key pointsEight weeks of Tai Chi Chuan combined with vibration training can more efficiently improve balance control for an untrained young population.The positive training effect on the lower extremity muscle power induced by vibration stimuli during Tai Chi Chuan movements still remains significant because of SSC mechanism.Combining Tai Chi Chuan with vibration training is more efficient and does not decrease the overall training effects due to a cross-interaction of each other.

12.
Adv Sci (Weinh) ; : e2304409, 2023 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-37953443

RESUMO

Flexible pressure sensors are crucial force-sensitive devices in wearable electronics, robotics, and other fields due to their stretchability, high sensitivity, and easy integration. However, a limitation of existing pressure sensors is their reduced sensing accuracy when subjected to stretching. This study addresses this issue by adopting finite element simulation optimization, using digital light processing (DLP) 3D printing technology to design and fabricate the force-sensitive structure of flexible pressure sensors. This is the first systematic study of how force-sensitive structures enhance tensile strain stability of flexible resistive pressure sensors. 18 types of force-sensitive structures have been investigated by finite element design, simultaneously, the modulus of the force-sensitive structure is also a critical consideration as it exerts a significant influence on the overall tensile stability of the sensor. Based on simulation results, a well-designed and highly stretch-stable flexible resistive pressure sensor has been fabricated which exhibits a resistance change rate of 0.76% and pressure sensitivity change rate of 0.22% when subjected to strains ranging from no tensile strain to 20% tensile strain, demonstrating extremely low stretching response characteristics. This study presents innovative solutions for designing and fabricating flexible resistive pressure sensors that maintain stable sensing performance even under stretch conditions.

13.
Fa Yi Xue Za Zhi ; 28(1): 41-3, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22435337

RESUMO

OBJECTIVE: To establish a whole genome amplification testing system based on degenerate oligonucleotide primed-PCR (DOP-PCR) and to explore its reliability and sensitivity. METHODS: DOP-PCR amplified production was detected by fluorescent labeled multiplex STR amplification and capillary electrophoresis detection system to determine reliability and sensitivity of DOP-PCR system. RESULTS: DOP-PCR system was successfully established and the detection sensitivity reached 5 cells (30 pg) by pretreatment of DOP-PCR and then detection of STR genotyping. CONCLUSION: The system established in this study is reliable and more testing sensitive for forensic trace evidence.


Assuntos
Primers do DNA , DNA/análise , DNA/genética , Reação em Cadeia da Polimerase/métodos , Sequências de Repetição em Tandem , Impressões Digitais de DNA/métodos , Eletroforese Capilar , Amplificação de Genes , Genótipo , Humanos , Técnicas de Amplificação de Ácido Nucleico , Oligonucleotídeos/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Forensic Sci Res ; 7(3): 560-565, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36353326

RESUMO

Since the start of the COVID-19 pandemic, there has been an urgent need to produce accurate and sensitive tests. However, there have been instances where a positive nucleic acid test turns negative after treatment, and then positive again. This case report describes such an instance from the tropical region of Hainan, China. The patient was a 61-year-old female who went to Hainan on vacation from Wuhan during the COVID-19 pandemic in 2020. Symptoms appeared 9 d after arriving in Hainan, and it was confirmed that the nucleic acid test was positive after 4 repeats. Her condition declined rapidly, her heart stopped beating, and she was admitted in a coma to the ICU. After treatment, the SARS-CoV-2 virus nucleic acid test of several nasopharyngeal swabs were negative, and tests on whole blood, anal swabs, and urine were also negative. Later, however, nucleic acid tests on a lower respiratory tract sputum swab and lower respiratory tract lavage fluid were positive. An autopsy examination was carried out 12 h after her death, and multi-organ secretions were extracted for nucleic acid testing. The SARS-CoV-2 virus nucleic acid was only detected in the swabs from the end of the bronchus, which was confirmed by the visualization of the coronavirus by electron microscopy. Autopsy confirmed that the damage was mainly concentrated in the lungs and immune organs and tissues throughout the body. Epidemiology indicated that none of the people she came into contact with after arriving in Hainan, including close contacts, were infected. This is in sharp contrast to the highly contagious virus in Wuhan in the temperate zone during the same period. This case report indicates: (1) The high temperatures in tropical areas may have an impact on the spread and harm of COVID-19, and (2) The reason why nucleic acid testing for COVID-19 was initially negative and then positive after treatment may be related to the survival of the SARS-CoV-2 virus in deep lung tissues.

15.
Polymers (Basel) ; 14(9)2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35567046

RESUMO

The structure, morphology, fracture toughness and flaw sensitivity length scale of chain-extended poly(butylene succinate) with various pre-stretch ratios were studied. PBS modification adopted from a multifunctional, commercially available chain-extension containing nine epoxy groups (ADR9) as the first step chain extension and hydroxyl addition modified dioxazoline (BOZ) as the second step. Time-temperature superposition (TTS) studies show that the viscosity increased sharply and the degree of molecular branching increased. Fourier transform infrared spectroscopy (FT-IR) confirm successful chain extension reactions. The orientation of the polymer in the pre-stretch state is such that spherulites deformation along the stretching direction was observed by polarized light optical microscopy (PLOM). The fracture toughness of sample (λfix = 5) is Γ ≈ 106 J m-2 and its critical flaw sensitivity length scale is Γ/Wc ≈ 0.01 m, approximately 5 times higher than PBS without chain-extension (Γ ≈ 2 × 105 J m-2 and Γ/Wc ≈ 0.002 m, respectively). The notch sensitivity of chain-extended PBS is significantly reduced, which is due to the orientation of spherulites more effectively preventing crack propagation. The principle can be generalized to other high toughness material systems.

16.
Sci China Life Sci ; 65(3): 604-617, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34185240

RESUMO

The smooth transportation of substances through the brain extracellular space (ECS) is crucial to maintaining brain function; however, the way this occurs under simulated microgravity remains unclear. In this study, tracer-based magnetic resonance imaging (MRI) and DECS-mapping techniques were used to image the drainage of brain interstitial fluid (ISF) from the ECS of the hippocampus in a tail-suspended hindlimb-unloading rat model at day 3 (HU-3) and 7 (HU-7). The results indicated that drainage of the ISF was accelerated in the HU-3 group but slowed markedly in the HU-7 group. The tortuosity of the ECS decreased in the HU-3 group but increased in the HU-7 group, while the volume fraction of the ECS increased in both groups. The diffusion rate within the ECS increased in the HU-3 group and decreased in the HU-7 group. The alterations to ISF drainage and diffusion in the ECS were recoverable in the HU-3 group, but neither parameter was restored in the HU-7 group. Our findings suggest that early changes to the hippocampal ECS and ISF drainage under simulated microgravity can be detected by tracer-based MRI, providing a new perspective for studying microgravity-induced nano-scale structure abnormities and developing neuroprotective approaches involving the brain ECS.


Assuntos
Espaço Extracelular/diagnóstico por imagem , Hipocampo/patologia , Imageamento por Ressonância Magnética/métodos , Simulação de Ausência de Peso , Animais , Líquido Extracelular , Hipocampo/diagnóstico por imagem , Masculino , Ratos , Ratos Sprague-Dawley
17.
Br J Psychiatry ; 198(1): 31-6, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21200074

RESUMO

BACKGROUND: Little is known about outcomes after self-harm in East Asia. AIMS: To investigate mortality after self-harm in a Taiwanese population. METHOD: Between 2000 and 2003, 1083 individuals who self-harmed were identified through a population self-harm register in Nantou County, Taiwan, and followed until 2007 for date and cause of death on a national mortality database. RESULTS: In total, 145 individuals died, 48 through suicide. The risks of all-cause and suicide mortality in the first year were 4.7% and 2.1% respectively, representing 8- and 131-fold age- and gender-standardised increases. Male gender and older age were independent risk factors for both suicide and non-suicide mortality. Use of more lethal methods in the index episode was associated with higher mortality but this was accounted for by gender. CONCLUSIONS: Results in this sample support the recommendation that people with a history of recent self-harm should be a major target for suicide prevention programmes.


Assuntos
Comportamento Autodestrutivo/mortalidade , Suicídio/estatística & dados numéricos , Adulto , Fatores Etários , Idoso , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Suicídio/tendências , Taiwan/epidemiologia
18.
Br J Psychiatry ; 196(1): 31-5, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20044656

RESUMO

BACKGROUND: Repeated self-harm is relatively common and is linked with an elevated risk of eventual suicide. There has been no study of this involving a large sample from the Far East. AIMS: To estimate the risk over the medium term of non-fatal repetition of self-harm and identify predictive factors in those carrying out self-harm. METHOD: A total of 970 individuals who had self-harmed were recruited from a community-based suicide behaviour register system in Nantou, Taiwan from July 2000 to February 2003. Information regarding demography and suicide methods was collected. Individuals were followed-up until December 2005 to examine the risk of repeated self-harm and independent predictive factors. RESULTS: Ninety cohort members had repeated self-harm during the follow-up period (accounting for 131 repeated self-harm episodes in all). The cumulative risks were 5.7% for the first year, 7.8% for the second year and 9.5% for the fourth year. The risk was highest within the first year after the self-harm event. Independent risk factors included female gender and self-cutting as well as self-poisoning with drugs. Effect of younger age was mediated through the choice of methods. CONCLUSIONS: Individuals with self-harm have a high risk of repetition, especially within the first year. Suicide prevention strategies need to focus on intervening with this population to reduce their repetition.


Assuntos
Comportamento Autodestrutivo , Prevenção do Suicídio , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Prevenção Secundária , Comportamento Autodestrutivo/epidemiologia , Taiwan/epidemiologia , Adulto Jovem
19.
Forensic Sci Int Genet ; 37: e6-e11, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30279073

RESUMO

The Ong Be language, an important branch of the Tai-Kadai language family, is one of the most distinctive languages on Hainan Island. Ong Be language speakers, who have lived in the Lingao district of Hainan Island for generations, were classified as Han Chinese in the early days of the establishment of the People's Republic of China but have distinct differences from the Han Chinese in language, lifestyle, customs and values and particularly in appearances and features. Currently, Y-chromosomal short tandem repeat (STR) haplotypes have been widely used in genetic applications, such as human forensics, historical investigations and genealogical research. In this study, 487 unrelated male individuals residing in the Lingao district volunteered, and their Y-STR haplotypes were investigated using the Yfiler and Yfiler Plus with 17 and 27 Y-STR loci, respectively. Furthermore, we combined our population data on the Lingao people with existing datasets from Asian nations (East, South and Southeast Asia) to explore the genetic variance and relationships with Han Chinese from different administrative regions in Northern and Southern China and Chinese ethnic minorities officially recognized by the PRC. Population comparisons demonstrated that the Lingao people had distant relationships with Asian nations at the national level and had relatively close genetic and linguistic relationships with Hainan Li and Guizhou Gelao, both of whom belong to the Tai-Kadai language family. The present results increase our understanding of the genetic relationships between the Lingao people and other groups, and further research in genetics and other areas is still needed to trace the origin of the Lingao people.


Assuntos
Cromossomos Humanos Y , Etnicidade/genética , Genética Populacional , Repetições de Microssatélites , Filogenia , Povo Asiático/genética , China , Impressões Digitais de DNA , Frequência do Gene , Variação Genética , Haplótipos , Humanos , Masculino , Reação em Cadeia da Polimerase
20.
NeuroRehabilitation ; 43(4): 509-518, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30400109

RESUMO

BACKGROUND: Traditional Tai Chi is too complex for most elderly individuals. There have been few reports regarding the development of simplified Tai Chi programs to suit the physical needs of elderly adults. However, these programs were not individualized according to the participants' balance control abilities. OBJECTIVE: Purpose of this study is to develop an individualized Tai Chi program and report the feasibility of the program. METHODS: Phase 1: Five Tai Chi masters performed the Tai Chi movements on a force platform. Based on the results of center of pressure displacement and the individual's balance abilities, an individualized program was developed.Phase 2: Ten community-dwelling older adults received 24 half-hour-sessions, using the individualized Tai Chi exercise program. The Berg Balance Scale (BBS) score, Timed Up & Go (TUG) test, forward reach, and strength of the knee extensor were determined before and after intervention. RESULTS: Participants achieved improved performance on balance control as measured with BBS (p≤0.001), TUG (p = 0.004) and forward reach (p = 0.035) as well as knee extensor strength (p = 0.002) after the program. CONCLUSIONS: This preliminary result suggests that the individualized Tai Chi program is potentially effective to improve balance function and knee extensor strength of the elderly.


Assuntos
Força Muscular , Equilíbrio Postural , Tai Chi Chuan/métodos , Idoso , Feminino , Humanos , Joelho/crescimento & desenvolvimento , Joelho/fisiologia , Masculino , Projetos Piloto
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