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1.
Opt Express ; 32(6): 10479-10489, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571258

RESUMO

We demonstrate an efficient active Q-switched Ho:GdVO4 self-Raman laser at 2500 nm for the first time, to our knowledge. Using Ho:GdVO4 crystal as the gain medium for both the 2048nm fundamental laser and the 2500 nm Raman laser, the output performances of a new mid-infrared self-Raman laser were investigated. The maximum average output power of 1.45 W was achieved at an incident pump power of 22.5 W, with a slope efficiency of 25.8%, for an output transmittance of 30% and a pulse repetition frequency of 15 kHz. The maximum single pulse energy of 96.7 µJ with a pulse width of 11.35 ns was obtained, corresponding to the peak power of 8.5 kW. The beam quality was near diffraction limited with the M2 factors of 1.15 and 1.06 along the x and y directions. Moreover, adopting the two-end output way of the fundamental laser and the Raman laser, the Raman gain coefficient of Ho:GdVO4 crystal was estimated to be 1.14 cm/GW at 2048nm. This work shows that Ho:GdVO4 is an excellent self-Raman laser crystal for the generation of high power Raman laser at 2.5 µm.

2.
Opt Lett ; 49(8): 2073-2076, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621079

RESUMO

A self-mode-locked Ho:GdVO4 laser with the GHz pulse repetition frequency oscillation near 2.06 µm was demonstrated for the first time to our knowledge. The output performances of the self-mode-locked Ho:GdVO4 laser were investigated for a few output coupler transmittances at the pulse repetition frequency of 1.89 GHz. At the incident pump power of 8.12 W, the maximum average output power was as high as 2.28 W, corresponding to the slope efficiency and optical-to-optical efficiency of 36.3% and 28.1%, respectively. This is the maximum average output for the 2 µm self-mode-locked solid-state laser with a GHz pulse repetition frequency. This work provides a new way for generating an efficient and a high-power ultrafast pulse laser with a GHz repetition frequency in the 2 µm wave band.

3.
BMC Geriatr ; 24(1): 260, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38500043

RESUMO

BACKGROUND: Nutrition and exercise are important interventions for sarcopenia. There were few studies on oral oligopeptide nutrition preparations combined with exercise to intervene in the older people with sarcopenia. The aim of this study was to verify the effectiveness of oligopeptide nutrition preparation combined with exercise intervention on the older people with sarcopenia in community. METHODS: A total of 219 subjects aged 65 years or older with sarcopenia were randomly divided into 4 groups. The nutrition group (n = 58) was given individualized nutrition education and oral oligopeptide nutrition preparation. The exercise group (n = 50) received exercise intervention. The combined group (n = 52) received both oral nutrition preparation and exercise interventions. The control group (n = 59) only received individualized nutrition education. The nutrition preparation can provide energy 185kcal and protein 24.2g per day. The exercise intervention including warm-up exercise, resistance exercise and aerobic exercise, the training time was 60min for 5 times every week. The intervention lasted for 16 weeks. Hand grip strength, gait speed, body composition and hematology parameters were measured before and after intervention. RESULTS: A total of 159 subjects completed the study. Compared with baseline, the left grip strength and 6-m walking speed of the subjects in nutrition group increased significantly after the intervention, and the grip strength of both hands in exercise group and combined group increased significantly. The body weight of the subjects in nutrition group, exercise group and combined group increased significantly after intervention, but no increase in soft lean mass (SLM) and skeletal muscle mass (SMM) was observed in any of the four groups. The fat-free mass (FFM) of the legs of the control group, exercise group and nutrition group decreased after intervention, and only the FFM of the legs of the combined group maintained the level before the intervention. CONCLUSION: Both oral peptide nutrition and exercise interventions can improve the muscle strength or function of the older people with sarcopenia. However, there were no increases in muscle mass observed. TRIAL REGISTRATION: ChiCTR, ChiCTR2100052135. Registered 20 October 2021, https://www.chictr.org.cn/showproj.html?proj=135743.


Assuntos
Treinamento de Força , Sarcopenia , Humanos , Idoso , Sarcopenia/terapia , Força da Mão , Força Muscular/fisiologia , Terapia por Exercício , Oligopeptídeos , Músculo Esquelético
4.
BMC Neurol ; 23(1): 341, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37759178

RESUMO

BACKGROUND: Dementia is characterized by progressive neurodegeneration and therefore early intervention could have the best chance of preserving brain health. There are significant differences in health awareness, living customs, and daily behaviors among Chinese older adults compared to Europeans and Americans. Because the synergistic benefits of multidomain non-pharmacological interventions are consistent with the multifactorial pathogenicity of MCI, such interventions are more appealing, easier to adhere to, and more relevant to daily life than single-mode interventions. One of the aims of this study is to verify the effect of multidomain intervention strategies for MCI patients based on Chinese population characteristics, and the other is to establish a biobank and image database to investigate the pathogenesis and pathways of cognitive impairment. METHODS: Our study was designed as a national multicenter, community-based randomized controlled trial (RCT). Twelve medical institutions in ten Chinese cities will participate in our study from 2020 to 2024, and 1080 community residents aged 50 and above will be enrolled as participants. Each sub-center will be responsible for 90 participants (30 people per community) across three communities (non-contact control group, health education group, and multidomain intervention group). The community will be the basic unit of the present study, and all participants in each community will receive the same intervention/control measure. Three working groups are set up in each sub-center to manage the three communities independently to minimize interference at the implementation level between the groups. The multidomain intervention group will receive integrated interventions including exercise, nutrition, sleep, health education and mindfulness meditation. All data generated by the research will be analyzed and processed by statistical software (such as SPSS 21.0, Python 3.0, etc.), and part of the research data will be displayed in the form of graphs and tables. DISCUSSION: In order to achieve a high-quality community intervention study, it is crucial to have a well-designed experimental protocol that follows rigorous scientific methodology. In addition, effective management of quality control measures and monitoring compliance throughout the study process are essential components. This study provides a detailed discussion of stakeholder compliance, research quality control, potential harm and mitigation, auditing, and future plans in order to better address research issues. TRIAL REGISTRATION: ChiCTR2000035012 (July 27, 2020).


Assuntos
Disfunção Cognitiva , Terapia por Exercício , Humanos , Idoso , Terapia por Exercício/métodos , Disfunção Cognitiva/terapia , Disfunção Cognitiva/psicologia , Exercício Físico , Encéfalo , Sono , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
5.
Opt Lett ; 48(13): 3495-3498, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37390164

RESUMO

A dual-wavelength passively Q-switched Ho:GdVO4 self-Raman laser in the 2.5 µm wave band was demonstrated with Cr:ZnS as a saturable absorber. Synchronized dual-wavelength pulsed laser outputs at 2473 nm and 2520 nm were acquired, corresponding to Raman frequency shifts of 808 cm-1 and 883 cm-1, respectively. The maximum total average output power of 114.9 mW was obtained at an incident pump power of 12.8 W with a pulse repetition rate of 3.57 kHz and a pulse width of 16.36 ns. The maximum total single pulse energy was 32.18 µJ, corresponding to a total peak power of 1.97 kW. The power ratios of the two Raman lasers can be controlled by varying the incident pump power. To the best of our knowledge, this is the first time a dual-wavelength passively Q-switched self-Raman laser in the 2.5 µm wave band has been reported.


Assuntos
Lasers , Frequência Cardíaca
6.
Opt Express ; 31(10): 15712-15721, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157665

RESUMO

A power balanced orthogonally polarized dual-wavelength Ho:GdVO4 laser was demonstrated for the first time. Without inserting any other devices into the cavity, the power balanced simultaneous orthogonally polarized dual-wavelength laser at π-polarization 2048nm and σ-polarization 2062nm was successfully achieved. At the absorbed pump power of 14.2 W, the maximum total output power was 1.68 W, and the output powers of 2048nm and 2062nm were 0.81 W and 0.87 W, respectively. The interval between the two wavelengths in the orthogonally polarized dual-wavelength Ho:GdVO4 laser was nearly 14nm, corresponding to the frequency separation of 1 THz. This power balanced orthogonally polarized dual-wavelength Ho:GdVO4 laser can be applied to generate the terahertz wave.

7.
Dysphagia ; 38(1): 415-424, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35789425

RESUMO

Recent studies have correlated dysphagia with ultrasound-measured quadriceps muscle mass and quality. Computed tomography (CT) is more precise than ultrasound for estimating muscle mass and quality. We aimed to investigate the possible associations of chest CT-determined trunk muscle mass and quality with dysphagia. A cross-sectional study. Older inpatients in a geriatric department of a university hospital. Self-reported dysphagia was determined by the Dysphagia Handicap Index. Unenhanced chest CT images were segmented to calculate skeletal muscle area (SMA) and intermuscular adipose tissue (IMAT). Skeletal muscle index (SMI) was calculated via SMA/ height squared. The percentage of IMAT (IMAT%) was calculated by IMAT% = IMAT/ (SMA + IMAT) × 100%. Mimics software was applied to calculate the mean skeletal muscle radio density (SMD).The semiquantitative food frequency method, the Barthel Index (BI), and the Mini Nutritional Assessment Short-Form (MNA-SF) were used to evaluate energy intake, activities of daily living, and nutrition status, respectively. Among the 212 participants (mean age: 84 years), 89 (42%) had self-reported dysphagia. After adjustment for age, nutrition status, energy intake, and other confounders, the SMI (adjusted OR 0.91, 95% CI 0.86, 0.96) was negatively associated with dysphagia, whereas the IMAT (adjusted OR 1.08, 95% CI 1.01, 1.16) and the IMAT% (adjusted OR 1.10, 95% CI 1.04,1.17) were positively associated with dysphagia. However, the SMD (adjusted OR 0.99, 95% CI 0.94, 1.05) was not significantly associated with dysphagia. The subgroup analyses indicated that only the SMI (adjusted OR 0.92, 95% CI 0.86, 0.97) and the IMAT% (adjusted OR 1.08, 95% CI 1.01, 1.17) were significantly associated with dysphagia in men. None of these indicators was significantly associated with dysphagia in women. Trunk muscle mass and quality (estimated by chest CT-derived SMI and IMAT%, respectively) were significantly associated with self-reported dysphagia in older inpatients, especially in men. IMAT% might be a more sensitive muscle quality indicator than IMAT (or SMD). These results merit further investigation in prospective studies.


Assuntos
Transtornos de Deglutição , Sarcopenia , Masculino , Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/complicações , Autorrelato , Estudos Prospectivos , Atividades Cotidianas , Pacientes Internados , Estudos Transversais , Indicadores de Qualidade em Assistência à Saúde , Músculo Esquelético/diagnóstico por imagem , Sarcopenia/complicações
8.
BMJ Open ; 12(6): e055420, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35738656

RESUMO

INTRODUCTION: Obesity is a public health challenge worldwide. To maintain a healthy weight, dieting and lifestyle changes are the first-line interventions; however, these interventions are of poor compliance and may cause body composition changes, mainly skeletal muscle wasting (sarcopenia). Dietary supplements for improving body composition while inducing weight loss are therefore needed. ß-hydroxy-ß-methylbutyrate (HMB) has been proven to be effective for improving muscle mass and muscle strength in athletes, older adults and patients with cancer. We aim to evaluate the effectiveness and safety of HMB-enriched nutritional supplements for improving muscle mass and muscle function in obese adults during calorie restriction. METHOD AND ANALYSIS: A total of 72 Chinese adults with obesity will be randomised to receive HMB-enriched nutritional supplements (65 g/day) or a placebo for 12 weeks. Participants in both groups will also receive calorie restrictions based on the individualised nutrition guidance of dietitians. Participants and investigators will be blinded to the allocations. The primary outcome will be the mean change in whole-body skeletal muscle mass (measured by bioelectrical impedance analysis). The secondary outcomes will include the mean change of appendicular skeletal muscle mass, body fat mass, basal metabolic rate, phase angle, muscle function and serum biomarkers. The enrolment will commence in December 2021 and will proceed until March 2022. ETHICS AND DISSEMINATION: This protocol has been approved by the Biomedical Ethics Committee of West China Hospital (2021-771). All potential subjects will be required to sign a written informed consent. The results of this study will be reported in peer-reviewed academic journals and conferences. TRIAL REGISTRATION NUMBER: NCT04953936.


Assuntos
Músculo Esquelético , Valeratos , Idoso , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Músculo Esquelético/fisiologia , Obesidade/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Redução de Peso
9.
Front Med (Lausanne) ; 8: 743698, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778305

RESUMO

Objectives: Sarcopenia is an important predictor of dependence in activities of daily living (ADL disability); however, the association between muscle quality and ADL disability has not been established. We aimed (1) to assess the feasibility of measuring trunk muscle mass and muscle quality by chest CT images; and (2) to explore the possible associations of ADL disability with these muscle mass and muscle quality indicators among older inpatients. Methods: We included older patients in an acute care ward. ADL disability was defined as the Barthel Index (BI) score ≤ 60 points. Unenhanced chest CT images at the 12th thorax (T12) vertebral level were used to segment skeletal muscle area (SMA) and intermuscular adipose tissue (IMAT) and to measure the mean skeletal muscle radiodensity (SMD). Skeletal muscle index (SMI), the muscle mass indicator, was calculated by SMA (cm2)/body height squared (m2). The percentage of IMAT (IMAT%) was calculated using the equation: IMAT% = IMAT/(SMA+ IMAT) ×100%. Skeletal muscle radiodensity, IMAT, and IMAT% were the muscle quality indicators. Kendall's tau rank correlation coefficients (τ) were calculated to explore the correlations. Univariate and multivariate logistic regression models were performed to calculate odds ratios (OR) and 95% confidence interval (CI). Results: We included 212 participants. Skeletal muscle index and SMD were positively and significantly associated with the BI score (τ = 0.14 and 0.31, respectively, both P < 0.001); whereas IMAT and IMAT% were negatively and significantly associated with the BI score (τ = -0.21, P < 0.001; τ = -0.21, P < 0.012). After adjusting for confounders, SMI (adjusted OR 1.03, 95% CI 0.97-1.09) was not independently associated with ADL disability; however, SMD (adjusted OR 0.94, 95% CI 0.88-0.99), IMAT (adjusted OR 1.11, 95% CI 1.03-1.20), and IMAT% (adjusted OR 1.09, 95% CI 1.02-1.16) were independently associated with ADL disability. Subgroup analysis found similar results in men; however, none of these indicators were independently associated with ADL disability in women. Conclusion: Trunk muscle quality indicators (SMD, IMAT, and IMAT%) measured by chest CT images, but not SMI, are independently associated with ADL disability in a single-center study population of older inpatients, especially in men. Further research is necessary to validate our findings.

11.
J Am Med Dir Assoc ; 16(8): 714.e7-714.e12, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26139596

RESUMO

OBJECTIVE: To determine the prevalence of frailty in older diabetic inpatients using the FRAIL scale and to evaluate the association of frailty with physical function and diabetic vascular complications, as well as its relationship to hospitalization and mortality. METHODS: This pilot study was conducted at the Center of Gerontology and Geriatrics, West China Hospital. A total of 146 inpatients aged 60 years or older with type 2 diabetes were enrolled between December 2011 and October 2012, and participants were followed until December 2013. Frailty, functional status, diabetic nephropathy, and macroangiopathy were assessed at enrollment. The longitudinal outcomes were hospitalization and mortality. Frailty was determined by the 5-item FRAIL scale. Functional status was determined using activities of daily living (ADLs), instrumental activities of daily living (IADLs), and timed "Up and Go" test (TUG). RESULTS: At baseline, 47.2% of participants were robust, 37.7% were prefrail, and 15.1% were frail. After adjusting for age, gender, MMSE score, body mass index (BMI), and the duration and severity of diabetes, both prefrailty and frailty were significantly associated with ADL disability (odds ratio [OR] 2.84 and 6.58, respectively), mobility impairment (OR 3.89 and 22.15, respectively), and diabetic nephropathy (OR 4.31 and 4.46, respectively). In the year after enrollment, the proportion of participants with 3 or more hospitalizations was 16.0% among robust participants, 23.6% among prefrail participants, and 40.9% among frail participants. Being frail predicted a greater number of hospitalizations (OR 5.99). There was no cumulative mortality for robust participants, whereas 3.6% of prefrail participants and 22.7% of frail participants died during follow-up (P < .001). CONCLUSION: In older diabetic inpatients in China, frailty is an independent risk factor for adverse health outcomes. Clinicians could use the FRAIL scale to regularly identify individuals who are frail or who are at risk of becoming frail.


Assuntos
Diabetes Mellitus Tipo 2 , Idoso Fragilizado , Avaliação Geriátrica , Atividades Cotidianas , Idoso , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Valor Preditivo dos Testes , Prevalência , Fatores de Risco
12.
Br J Nutr ; 109(2): 263-72, 2013 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-22717016

RESUMO

The present study investigated the potential health-promoting effects of heat-inactivated Lactobacillus gasseri TMC0356 (TMC0356) on the metabolic syndrome (MS) and the probable mechanisms underlying these effects using an MS rat model. For the purpose of the study, sixty Sprague-Dawley rats were randomly divided into five groups: a control group fed a conventional diet, an MS model group fed a high-fat and high-salt (HFS) diet and three TMC0356 test groups (low-, medium- and high-dose groups) fed an HFS diet supplemented with TMC0356 at 41.8, 83.5 and 167.0 mg/kg body weight (BW) per d, respectively. Food intake and BW were measured weekly. Fasting blood glucose (FBG), lipid profiles and blood pressure (BP) were measured at 0, 5, 10 and 15 weeks. Organ coefficients, immune cell counts and serum insulin, adiponectin, C-reactive protein (CRP), IL-6, TNF-α, IgG and secretory IgA levels were measured at the 15th week after diet intervention. The HFS diet increased the BW, liver or fat:BW ratio, FBG, homeostatic model assessment of insulin resistance, adiponectin, serum LDL-cholesterol and total cholesterol levels and BP (P< 0.01). Average food and energy intakes in the three TMC0356 groups were significantly lower than those of the MS model group. All the metabolic indices, except BP, were markedly improved (P< 0.05) by oral administration of low and medium doses of TMC0356. The thymus index in the medium-dose group and lymphocyte, CRP, IL-6, TNF-α and IgG levels in all the three TMC0356 groups were significantly increased (P< 0.05 or P< 0.01) compared with those in the MS model group. These results suggest that TMC0356 can improve the metabolic characteristics of MS rats by suppressing appetite. Additionally, the enhancement of inflammatory immune response may be, at least in part, the mechanism underlying the health-promoting effects of TMC0356 on the MS.


Assuntos
Fármacos Antiobesidade/uso terapêutico , Suplementos Nutricionais , Fatores Imunológicos/uso terapêutico , Lactobacillus/imunologia , Síndrome Metabólica/imunologia , Síndrome Metabólica/prevenção & controle , Obesidade/prevenção & controle , Adiposidade , Animais , Fármacos Antiobesidade/administração & dosagem , Modelos Animais de Doenças , Relação Dose-Resposta Imunológica , Temperatura Alta , Fatores Imunológicos/administração & dosagem , Resistência à Insulina , Gordura Intra-Abdominal/imunologia , Gordura Intra-Abdominal/patologia , Fígado/imunologia , Fígado/patologia , Masculino , Síndrome Metabólica/complicações , Síndrome Metabólica/patologia , Viabilidade Microbiana , Obesidade/complicações , Tamanho do Órgão , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Timo/imunologia , Timo/patologia
13.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 42(3): 353-7, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21826998

RESUMO

OBJECTIVE: To identify risk factors associated with gestational diabetes mellitus (GDM) and establish a risk appraisal model for GDM. METHODS: A case-control study of 156 women with GDM and 362 pregnant women without GDM was undertaken. Non-conditional logistic regression analysis was performed to identify risk factors associated with GDM and establish a prediction model. The diagnostic efficiency of this model was estimated by receiver operator characteristic curve (ROC) and Hosmer-lemeshow goodness-of-fit. RESULTS: Age, high blood pressure, history of poor pregnant outcome, obesity before pregnancy, excessive consumption of fruits, history of DM of immediate family members and taste preference were identified as risk factors of GDM. High consumption of white meat was identified as a protective factor. When the threshold value was set at 3.6, maximum sensitivity (73.7%) and specificity (68.5%) was obtained. The area under curve (AUC) of ROC was 0.79, with Hosmer-lemeshow P = 0.97. CONCLUSION: The developed model has high diagnostic efficiency, which provides a good instrument for screening women with high-risk GDM.


Assuntos
Diabetes Gestacional/etiologia , Modelos Logísticos , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Gravidez , Medição de Risco , Fatores de Risco
14.
Wei Sheng Yan Jiu ; 39(2): 209-11, 227, 2010 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-20459038

RESUMO

OBJECTIVE: To explore the life style and diet of pregnant women related to gestational diabetes mellitus (GDM) in order to provide scientific evidences for the prevention of GDM. METHOD: A total of 450 subjects were recruited in a 1:2 matched case-control study including 150 pregnant women diagnosed as GDM and 300 normal pregnant women. All subjects participated in a questionnaire survey on socio-demographic characteristics, pregnancy relevant status, dietary structure and lifestyle. Conditional logistic regression analysis and t-test were used for the evaluation of relevant factors. RESULT: There was a statistic significance of the difference between the two groups on total calorie, carbohydrate, fat and protein intakes per day (P < or = 0.01). Twenty-three factors based on univariate analysis were associated with the occurrence of GDM. Seven factors were entered into the last logistic multivariate regression model. High blood pressure (OR = 28.50), adverse pregnant history (OR = 3.10), obesity before pregnancy (OR = 2.80), too much consumption of fruits (OR = 2.40), family history of DM (OR = 1.86) and favorite of sweets (OR = 1.68) were risk factors for GDM, while the consumption of more white meat was a protective factor (OR = 0.62). CONCLUSION: The occurrence of GDM was influenced by some adverse lifestyles, unreasonable dietary structure and other factors, such as hypertension, over weight before gestation and family history of DM. Measures should be taken to avoid and eliminate these risk factors.


Assuntos
Diabetes Gestacional/prevenção & controle , Dieta , Estilo de Vida , Adulto , Estudos de Casos e Controles , China , Diabetes Gestacional/etiologia , Feminino , Humanos , Modelos Logísticos , Gravidez , Fatores de Risco , Inquéritos e Questionários
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