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1.
Hong Kong Med J ; 30(3): 233-240, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38825732

RESUMO

The surgical management of obesity in Hong Kong has rapidly evolved over the past 20 years. Despite increasing public awareness and demand concerning bariatric and metabolic surgery, service models generally are not standardised across bariatric practitioners. Therefore, a working group was commissioned by the Hong Kong Society for Metabolic and Bariatric Surgery to review relevant literature and provide recommendations concerning eligibility criteria for bariatric and metabolic interventions within the local population in Hong Kong. The current position statement aims to provide updated guidance regarding the indications and contraindications for bariatric surgery, metabolic surgery, and bariatric endoscopic procedures.


Assuntos
Cirurgia Bariátrica , Obesidade , Humanos , Cirurgia Bariátrica/normas , Cirurgia Bariátrica/métodos , Hong Kong , Obesidade/cirurgia , Adulto , Endoscopia/métodos , Endoscopia/normas , Sociedades Médicas , Obesidade Mórbida/cirurgia
2.
Artigo em Chinês | MEDLINE | ID: mdl-34365762

RESUMO

Objective: To compare the quality of life of pneumoconiosis patients between from rural migrant workers and from a state-owned enterprises in Zhaotong City Yunnan Province, and to explore the factors influencing quality of life of pneumoconiosis patients. Methods: In August 2017, 83 patients from rural migrant workers in Zhaotong City Yunnan Province and 126 pneumoconiosis patients from a state-owned coal mining enterprises were selected as target population. World Health Organization on Quality of Life Brief Scale (WHOQOL-BREF) and self-designed questionnaires were used to collect information from two groups. The demographic information, health status and quality of life of two groups were compared. The factors influencing quality of life were analyzed by multi-liner regression analyses. Results: Average annual household income of rural migrant workers group was lower than that of state-owned enterprises group, and the average annual household expenditure for health of rural migrant workers group was higher than that of state-owned enterprises group (P<0.01) . Overall score of WHOQOL-BREF and scores for four domains including physiology, psychology, social relationship and environment of rural migrant workers group were lower than the scores of patients from state-owned enterprises group (P<0.01) . The result of multi-liner regression analysis showed that average annual household income (b=0.00015, 95%CI: 0.00010-0.00020) , being rural migrant workers (b=-5.904, 95%CI: -8.436--3.372) , better action ability (b=2.595, 95%CI: 0.706-4.483) and have complication (b=-2.542, 95%CI: -4.698--0.387) were factors influencing overall score of WHOQOL-BREF of pneumoconiosis patients (P<0.05) . Conclusion: The quality of life of pneumoconiosis patients from rural migrant workers is lower than that from state-owned enterprises. And the average annual household income, action ability and having complication or not are factors influencing the quality of life of pneumoconiosis patients.


Assuntos
Minas de Carvão , Pneumoconiose , Migrantes , China , Humanos , Qualidade de Vida , Inquéritos e Questionários
3.
Zhonghua Yi Xue Za Zhi ; 96(46): 3757-3761, 2016 Dec 13.
Artigo em Chinês | MEDLINE | ID: mdl-27998435

RESUMO

Objective: To evaluate the association of sleep quality with hypertension in the elderly population aged 60 years and older of Jino nationality. Methods: In August 2015, a cross-sectional population-based survey was conducted to investigate the prevalence of hypertension in 805 subjects sampled by multistage stratified and cluster sampling from the elderly population of Jino nationality, the sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI, a poor sleep group was defined as having a global PSQI score>7, a good sleep group was with a score of 7 or less), and the multilevel Logistic regression model was applied to analyze the association of sleep quality with hypertension. Results: A total of 793 eligible participants were available for analysis. Overall, 118 participants (14.9%) were in the poor sleep group, and 675 participants (85.1%) were in the good sleep group. The prevalence of hypertension, prevalence of isolated systolic hypertension, average systolic blood pressure (SBP) and diastolic blood pressure (DBP) of the poor sleep group were significantly high than those of the good sleep group[73.7%, 22.0%, (139.2±17.7) and (82.5±10.6) mmHg (1 mmHg=0.133 kPa) vs 33.0%, 9.0%, (131.2±15.0) and (78.5±8.9) mmHg, all P<0.05]. The results of covariate-adjusted multilevel Logistic regression model indicated that subjective sleep quality (OR=2.64, 95% CI: 1.08-6.44), sleep latency (OR=2.98, 95% CI: 1.52-5.86), sleep disturbance (OR=2.93, 95% CI: 1.06-8.10), daytime dysfunction (OR=3.86, 95% CI: 1.74-8.58) and poor sleep (OR=3.98, 95% CI: 2.05-7.73) had the positive correlation with hypertension. Conclusions: The elderly population of Jino nationality with poor sleep have high SBP and DBP. There are positive associations of PSQI and its components with hypertension in the elderly population of Jino nationality.


Assuntos
Hipertensão , Sono , Idoso , Pressão Sanguínea , Estudos Transversais , Etnicidade , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Prevalência , Distúrbios do Início e da Manutenção do Sono , Transtornos do Sono-Vigília
4.
Public Health ; 129(9): 1224-36, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26343546

RESUMO

OBJECTIVES: This study examines the associations of Internet addiction with social anxiety, depression, and psychosocial well-being among Asian adolescents. A self-medication model conceptualizing Internet addiction as a mediating role in relating depression and social anxiety to negative psychosocial well-being was tested. STUDY DESIGN: A cross-sectional survey. METHODS: In the Asian Adolescent Risk Behavior Survey (AARBS), 5366 adolescents aged 12-18 years from six Asian countries (China, Hong Kong, Japan, South Korea, Malaysia, and Philippines) completed a questionnaire with items of the Internet Addiction Test (IAT), Social Anxiety Scale for Adolescents (SAS-A), Center for Epidemiological Studies Depression Scale (CESD), Self-Rated Health of the Nation Outcome Scales for Children and Adolescents (HoNOSCA-SR) in the 2012-2013 school year. Structural equation modelling was used to examine the mediating role of Internet addiction in depression, social anxiety, and subjective psychosocial well-being. RESULTS: Significant differences on the scores of IAT, SAS-A, CESD, and HoNOSCA-SR across the six countries were found. The proposed self-medication model of Internet addiction received satisfactory goodness-of-fit with data of all countries. After the path from social anxiety to Internet addiction had been discarded in the revised model, there was a significant improvement of the goodness-of-fit in the models for Japan, South Korea, and the Philippines. CONCLUSIONS: Depression and social anxiety reciprocally influenced, whereas depression associated with poorer psychosocial well-being directly and indirectly through Internet addiction in all six countries. Internet addiction mediated the association between social anxiety and poor psychosocial well-being in China, Hong Kong, and Malaysia.


Assuntos
Comportamento do Adolescente/psicologia , Ansiedade/epidemiologia , Comportamento Aditivo/psicologia , Depressão/epidemiologia , Internet/estatística & dados numéricos , Comportamento Social , Adolescente , Ásia/epidemiologia , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Modelos Psicológicos , Inquéritos e Questionários
5.
Gene Ther ; 19(10): 999-1009, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22071974

RESUMO

We report on the long-term safety of AAV2.sFlt-1 (a recombinant adeno-associated virus serotype 2 carrying the soluble form of the Flt-1 receptor) injection into the subretinal space of non-human primates. Levels of sFlt-1 protein were significantly higher (P<0.05) in the vitreous of four out of five AAV2.sFlt-1-injected eyes. There was no evidence of damage to the eyes of animals that received subretinal injections of AAV2.sFlt-1; ocular examination showed no anterior chamber flare, normal fundus and electroretinography responses equivalent to those observed before treatment. Notably, immunological analysis demonstrated that gene therapy involving subretinal injection of AAV2.sFlt-1 does not elicit cell-mediated immunity. Biodistribution analysis showed that AAV2.sFlt-1 could be detected only in the eye and not in the other organs tested. These data indicate that gene therapy with subretinal AAV2.sFlt-1 is safe and well tolerated, and therefore promising for the long-term treatment of neovascular diseases of the eye.


Assuntos
Dependovirus/genética , Terapia Genética , Neovascularização Retiniana/terapia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Animais , Terapia Genética/efeitos adversos , Vetores Genéticos , Macaca fascicularis , Retina/imunologia , Retina/metabolismo , Neovascularização Retiniana/genética , Neovascularização Retiniana/imunologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/imunologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
6.
Eat Weight Disord ; 16(4): e289-92, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22526136

RESUMO

OBJECTIVE: This study examines the risks of disordered eating among Hong Kong adolescents. SUBJECTS: A total of 893 students (12-18 years old) participated in a cross-sectional study in 2007. METHODS: Students' height and weight were measured and the Eating Attitudes Test (EAT-26) was completed. The risks of disordered eating were assessed by EAT-26 results and weight status. Sex differences in the risks of disordered eating were examined by logistic regression models with adjustment for age. RESULTS: Based on the EAT-26 results, 18.5% of boys and 26.6% of girls were at risk of disordered eating with a significant adjusted odds ratio (OR) of 1.58 [95% confidence interval (CI) 1.15-2.18] for sex. A significant OR of 1.60 (95%CI 1.21-2.13) for sex was also obtained when both EAT-26 results and weight status were used for the screening. CONCLUSIONS: Hong Kong adolescent girls have a higher risk of disordered eating than boys. EAT-26 results together with measured weight status are useful criteria for screening disordered eating attitudes and behaviors in adolescents.


Assuntos
Peso Corporal , Comportamento Alimentar/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Adolescente , Comportamento do Adolescente/psicologia , Criança , Estudos Transversais , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Feminino , Hong Kong/epidemiologia , Humanos , Masculino , Prevalência , Fatores de Risco , Fatores Sexuais
7.
Opt Lett ; 35(2): 160-2, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20081954

RESUMO

We report a design for upconversion 435 nm blue lasers based on simultaneously fulfilling the nonlinear processes of optical parametric oscillation (OPO) and second-harmonic generation (SHG) in a 7.9 mum periodically poled lithium tantalate (PPLT). The uncoated 15-mm-long PPLT device exhibits a low threshold of 150 mW and a differential slope efficiency of 22.6%, rendering 56 mW blue generation when pumped by a pulsed 532 nm green laser with an average power rating of 400 mW. These observations were attributed to a quasi-phase-matching (QPM) structural design with a 75% domain duty cycle to ensure the concurrence of frequency doubling with the first-order QPM-OPO PPLT device via the second-order QPM-SHG process.

8.
Br J Ophthalmol ; 92(6): 832-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18523088

RESUMO

BACKGROUND/AIMS: Photoreceptor-specific upregulation of vascular endothelial growth factor (VEGF) in a transgenic mouse model (Kimba) of retinal neovascularisation induces retinal vascular damage which appears similar to that in diabetic retinopathy. Here we have determined whether the choroidal vasculature is also affected in Kimba. METHODS: Kimba mice were assessed with fundus fluorescein angiography for mild, moderate or severe retinal vascular leakage prior to preparation of choroidal corrosion casts for quantitative analysis using scanning electron microscopy. VEGF was located immunohistochemically. RESULTS: Choroidal abnormalities included microaneurysms, constriction, shrinkage and dropout in the capillaries and tortuosity and loops in the arteries and veins which were similar to those observed in corrosion casts of the human choroid in diabetes. Similar to human diabetes, choroidal neovascularisation was not observed. The severity of choroidal damage correlated with the extent of retinal vascular leakage. In addition to the expected presence of VEGF in photoreceptors, VEGF was also detected in the pigment epithelium and choroid in the transgenic mice. CONCLUSION: We show that elevated retinal VEGF levels trigger pathophysiological changes in the choroid. We suggest that therapies to prevent vascular damage in diabetes must target both the retinal and choroidal vasculatures.


Assuntos
Corioide/irrigação sanguínea , Neovascularização Retiniana/patologia , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Capilares/ultraestrutura , Corioide/química , Corioide/metabolismo , Molde por Corrosão , Angiofluoresceinografia , Fundo de Olho , Camundongos , Camundongos Transgênicos , Microscopia Eletrônica de Varredura , Modelos Animais , Fenótipo , Epitélio Pigmentado Ocular/química , Epitélio Pigmentado Ocular/metabolismo , Neovascularização Retiniana/metabolismo , Fator A de Crescimento do Endotélio Vascular/análise , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
J Pharm Biomed Anal ; 44(4): 996-1000, 2007 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-17499471

RESUMO

A rapid ultra performance liquid chromatography coupled with photo diode array detection method (UPLC-PDA) was developed for the simultaneous determination of 11 saponins, namely notoginsenoside R1, ginsenoside Rg1, Re, Rf, Rb1, Rg2, Rc, Rb2, Rb3, Rd and Rg3 in Panax notoginseng. The analysis was performed on Acquity UPLC system with Acquity UPLC BEH C(18) column and gradient elution of water and acetonitrile in 12 min. The high correlation coefficient (r(2)>0.9968) values indicated good correlations between the investigated compounds' concentrations and their peak areas within the test ranges. The LOQ and LOD were lower to 0.2-2.4 and 0.1-1.8 ng on column, respectively. The overall intra- and inter-day variations (R.S.D.) of 11 saponins were lower than 3.1%. The developed method was successfully used for the analysis of saponins in P. notoginseng with overall recovery of 93.0-101.6% for the analytes. The results show that UPLC is a powerful tool for analysis of components in Chinese medicines.


Assuntos
Panax notoginseng/química , Saponinas/análise , Calibragem , Cromatografia Líquida de Alta Pressão , Ginsenosídeos/análise , Raízes de Plantas/química , Reprodutibilidade dos Testes
10.
J Pharm Biomed Anal ; 44(3): 807-11, 2007 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-17459643

RESUMO

A high-performance liquid chromatography-diode array detector-mass spectrometry (HPLC-DAD-MS) analytical method was developed for detection of the nucleosides and nucleobases in two species of Lingzhi, the dried sporophore of Ganoderma lucidum and G. sinense. The method, combining advantages of both DAD and MS, was successfully used to qualitatively identify for six nucleosides namely, adenosine, cytidine, guanosine, inosine, thymidine, uridine and five nucleobases namely, adenine, guanine, hypoxanthine, thymine and uracil in Lingzhi samples. Quantitative analyses showed that uridine was the most abundant nucleoside in these Lingzhi samples and the contents of nine target analytes were found to be different in pileus and stipes of the fruiting bodies and among the different species of G. spp. The established method might apply as an alternative approach for the quality assessment of Lingzhi.


Assuntos
Adenina/análise , Cromatografia Líquida de Alta Pressão/métodos , Ganoderma/química , Guanina/análise , Hipoxantina/análise , Espectrometria de Massas/métodos , Nucleosídeos/análise , Timina/análise , Uracila/análise , Adenina/química , Carpóforos/química , Guanina/química , Hipoxantina/química , Estrutura Molecular , Nucleosídeos/química , Extratos Vegetais/química , Padrões de Referência , Reprodutibilidade dos Testes , Especificidade da Espécie , Tecnologia Farmacêutica/métodos , Timina/química , Uracila/química
11.
Diabetologia ; 49(7): 1690-701, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16752188

RESUMO

AIMS/HYPOTHESIS: Vascular endothelial growth factor (VEGF) plays a pivotal role in the pathogenesis of diabetic retinopathy. We investigated whether transgenic mice with moderate VEGF expression in photoreceptors (trVEGF029) developed changes similar to diabetic retinopathy and whether retinopathy progressed with time. MATERIALS AND METHODS: Human VEGF(165) (hVEGF(165)) expression was analysed using ELISA and quantitative RT-PCR; serum glucose levels were also measured. Fundus fluorescein angiography (FA) was used to screen the degree of retinopathy from 6 weeks. Dynamic changes in the density of retinal microvasculature, as well as other changes similar to diabetic retinopathy, including retinal leucostasis, capillary endothelial cell and pericyte loss, and numbers of acellular capillaries, were quantified. RESULTS: trVEGF029 mice were normoglycaemic and showed a moderate, short-term hVEGF(165) upregulation for up to 3 weeks. Changes in the retinal microvasculature not only mimicked those seen in diabetic retinopathy, but also showed similar pathological progression with time. FA at 6 weeks identified two phenotypes, mild and moderate, which were distinguished by the extent of vascular leakage. Quantitative analysis of diabetic retinopathy-like changes revealed that these parameters were tightly correlated with the initial degree of vascular leakage; low levels reflected slow and limited retinal microvascular changes in mild cases and high levels reflected more rapid and extensive changes in moderate cases. CONCLUSIONS/INTERPRETATION: The data suggest that even an early short-term elevation in hVEGF(165) expression might set a train of events that lead to progressive retinopathy. Induction of many features characteristic of diabetic retinopathy in trVEGF029 enables mechanisms leading to the disease state to be examined, and provides a relevant animal model for testing novel therapeutics.


Assuntos
Retinopatia Diabética/patologia , Vasos Retinianos/patologia , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Glicemia/análise , Angiopatias Diabéticas/metabolismo , Angiopatias Diabéticas/patologia , Retinopatia Diabética/complicações , Retinopatia Diabética/genética , Retinopatia Diabética/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Leucostasia/complicações , Leucostasia/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Vasos Retinianos/metabolismo , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/metabolismo
12.
J Pharm Biomed Anal ; 41(1): 274-9, 2006 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-16316736

RESUMO

A HPLC and pressurized liquid extraction (PLE) method was developed for simultaneous determination of nine saponins, including notoginsenoside R1, ginsenoside Rg1, Re, Rf, Rb1, Rc, Rb2, Rb3 and Rd in Panax notoginseng. The analysis was performed on C18 column with water-acetonitrile gradient elution and the investigated saponins were authenticated by comparing retention time and mass spectra with their reference compounds. Several methods including PLE, ultrasonication, soxhlet extraction and immersion were used for sample preparation and their extraction efficiency was compared. The results showed that PLE has the highest extraction efficiency and repeatability, which would be valuable on standardization of sample preparation for quality control of Chinese medicines. The developed HPLC and PLE is an effective approach for simultaneously quantitative determination of sapoinins in P. notoginseng, which could be used for quality control of P. notoginseng and its preparations.


Assuntos
Química Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/análise , Saponinas/análise , Tecnologia Farmacêutica/métodos , Calibragem , Cromatografia , Ginsenosídeos/análise , Ginsenosídeos/farmacologia , Espectrometria de Massas , Modelos Químicos , Panax/metabolismo , Extratos Vegetais/química , Saponinas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Fatores de Tempo
13.
J Pharm Biomed Anal ; 40(3): 669-78, 2006 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-16343839

RESUMO

'XUESETONG' injection, one of the most widely used proprietary medicines in traditional Chinese medicine, consists of total saponins made from Panax notoginseng, which is a highly valued and important Chinese medicinal herb. It is used to treat cardiovascular diseases. In order to control the quality of XUESETONG injection, a rapid HPLC-ESI-MS/MS method was developed for qualitative and quantitative determination of the saponins. The analyses were performed on SB-C18 column using gradient elution in 25 min. Full scan and time programmed selected reaction monitoring (SRM) were used for qualitative and quantitative analysis of saponins, respectively. Twenty-seven saponins were identified and nine of them including notoginsenoside R1, ginsenoside Rb1, Rb2, Rb3, Rc, Rd, Re, Rf and Rg1 were quantified. Ten XUESETONG injections were analyzed and compared. The results showed that there is a great variation among different samples. In conclusion, the developed method is rapid, accurate and sensitive for qualitative and quantitative analysis of saponins in XUESETONG injection. Moreover, it also can be used for the quality control of P. notoginseng raw material and its preparations.


Assuntos
Saponinas/análise , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas , Ginsenosídeos/análise , Injeções , Soluções Farmacêuticas/análise , Padrões de Referência , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta
14.
Br J Ophthalmol ; 89(7): 911-6, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15965177

RESUMO

AIM: To generate a mouse model for slow progressive retinal neovascularisation through vascular endothelial growth factor (VEGF) upregulation. METHODS: Transgenic mice were generated via microinjection of a DNA construct containing the human VEGF165 (hVEGF) gene driven by a truncated mouse rhodopsin promoter. Mouse eyes were characterised clinically and histologically and ocular hVEGF levels assayed by ELISA. RESULTS: One transgenic line expressing low hVEGF levels showed mild clinical changes such as focal fluorescein leakage, microaneurysms, venous tortuosity, capillary non-perfusion and minor neovascularisation, which remained stable up to 3 months postnatal. Histologically, there were some disturbance and thinning of inner and outer nuclear layers, with occasional focal areas of neovascularisation. By contrast, three other lines expressing high hVEGF levels presented with concomitantly severe phenotypes. In addition to the above, clinical features included extensive neovascularisation, haemorrhage, and retinal detachment; histologically, focal to extensive areas of neovascularisation associated with retinal folds, cell loss in the inner and outer nuclear layers, and partial retinal detachment were common. CONCLUSIONS: The authors generated four hVEGF overexpressing transgenic mouse lines with phenotypes ranging from mild to severe neovascularisation. These models are a valuable research tool to study excess VEGF related molecular and cellular changes and provide additional opportunities to test anti-angiogenic therapies.


Assuntos
Camundongos Transgênicos/genética , Neovascularização Retiniana/genética , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Retinopatia Diabética/genética , Retinopatia Diabética/patologia , Modelos Animais de Doenças , Angiofluoresceinografia/métodos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Descolamento Retiniano/genética , Descolamento Retiniano/patologia , Hemorragia Retiniana/genética , Hemorragia Retiniana/patologia , Neovascularização Retiniana/patologia , Vasos Retinianos/patologia , Vasos Retinianos/fisiologia , Regulação para Cima/genética
15.
J Chromatogr A ; 1036(2): 239-43, 2004 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-15146928

RESUMO

A simple method is described for the simultaneous determination of ergosterol, nucleosides and their bases in Cordyceps. The samples were extracted by using pressurised liquid extraction (PLE). The effects of experimental variables, such as solvent, temperature, static extraction time and cycles, on PLE efficiency have been studied. The results showed a strong influence of the solvent and temperature on extraction efficiency of PLE. The determination was achieved by high-performance liquid chromatography (HPLC) using a Zorbax NH2 analytical column (250 x 4.6 mm i.d., 5 microm) with diode-array detector (DAD). The automated preparation of the sample permits a very fast analysis which is an important goal for routine purpose.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cordyceps/química , Ergosterol/análise , Nucleosídeos/análise , Espectrofotometria Ultravioleta
16.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 1222-4, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-17271908

RESUMO

Optical coherence tomography (OCT) is analogous to ultrasound imaging except that it uses infrared light instead of sound. Polarization-sensitive optical coherence tomography (PS-OCT) combines the advantages of OCT and provides additional image contrast of the tested sample. We demonstrate this technique for imaging of back-reflected light, birefringence, and fast-axis orientation simultaneously in different kinds of atherosclerosis plaque. This in vitro study suggests birefringence changes in plaque are due to the prominent deposition of collagen or cholesterol by correlating PS-OCT images with histology. Thus the combination of high resolution structural imaging and birefringence detection make PS-OCT a potentially powerful tool for early assessment of atherosclerosis appearance and prediction of plaque rupture.

17.
Physiol Behav ; 79(4-5): 701-11, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12954412

RESUMO

Light entrainment of circadian rhythms is mediated by classical "visual" photoreceptors (rods and cones) as well as "nonvisual" photoreceptive elements (light-detecting cells that do not contribute to classical "vision"). This paper aimed to assess whether light entrainment of locomotor circadian rhythms in mice with impaired rods and cones differs from normal controls and whether this technique, alongside existing techniques, could be used to assess visual function. The study was primarily interested in differences between the entrainment of circadian rhythms of normal-sighted C57Bl/6J mouse and the C57Bl/RPE65 knockout mouse (RPE65(-/-)), although C3H/HeJ (rd/rd) mice were included as a preexisting model of retinal degeneration. Circadian rhythms of motor activity before and after a 12-h light reversal were assessed in custom-built cages that continuously monitored movement. The controls showed a significantly higher mesor and amplitude when compared to the RPE65(-/-) and rd/rd mice. Despite the loss of rods and cones, the RPE65(-/-) and rd/rd maintained a 24-h circadian rhythm entrained to light similar to controls and were capable of circadian reentrainment to a 12-h light reversal. Importantly, this light reentrainment of the circadian phase occurred at a significantly slower rate in the retinal degenerate models than in the controls. The RPE65(-/-) model demonstrates a retinal degenerate reentrainment phenotype when compared to the rd/rd model. It is suggested that these retinal degenerate mice retain the ability to detect light for the purposes of circadian rhythm entrainment. However, alterations of specific parameters of the circadian rhythm with loss of rods and cones may provide measures of loss of visual function (sight).


Assuntos
Ciclos de Atividade/efeitos da radiação , Ritmo Circadiano/efeitos da radiação , Proteínas do Olho/efeitos da radiação , Células Fotorreceptoras/fisiopatologia , Proteínas/efeitos da radiação , Degeneração Retiniana/fisiopatologia , Animais , Proteínas de Transporte , Proteínas do Olho/fisiologia , Luz , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fotoperíodo , Células Fotorreceptoras/efeitos da radiação , Epitélio Pigmentado Ocular/fisiologia , Epitélio Pigmentado Ocular/efeitos da radiação , Proteínas/fisiologia , Especificidade da Espécie , cis-trans-Isomerases
18.
Gene Ther ; 9(12): 804-13, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12040462

RESUMO

Neovascularisation (NV) within the eye often results in visual loss. Vascular endothelial growth factor (VEGF) has been implicated in the development of ocular NV. Previous studies have shown that VEGF antagonists successfully suppressed retinal and choroidal NV in animal models. However, the systemic approach and transient nature of the delivery systems used in these studies hinder therapeutic application. To achieve stable and localised ocular anti-angiogenic therapy, we explored the use of recombinant adeno-associated virus (rAAV)-mediated secretion gene therapy (SGT). In this study, we generated a rAAV vector encoding soluble VEGF receptor 1, sFlt-1 (AAV-CMV.sflt) and determined its ability to inhibit cautery-induced corneal NV and laser-induced choroidal NV. Delivery of AAV-CMV.sflt into the anterior chamber resulted in transgene expression in the iris pigment epithelium and corneal endothelium, which reduced the development of corneal NV in the stroma of cauterised rats by 36% compared with cauterised control groups (P = 0.009). Subretinal delivery of AAV-CMV.sflt near the equator of the eye also suppressed choroidal NV at the laser lesions around the optic nerve by 19% (P = 0.002), indicating that there was diffusion of the secreted anti-angiogenic protein across the retina. Both results suggest that the long-term suppression of ocular NV is possible through the use of stable rAAV-mediated SGT.


Assuntos
Adenoviridae/genética , Corioide/irrigação sanguínea , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Neovascularização Patológica/terapia , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/genética , Animais , Linhagem Celular , Células Cultivadas , Fatores de Crescimento Endotelial/metabolismo , Endotélio Corneano/metabolismo , Expressão Gênica , Iris/metabolismo , Linfocinas/metabolismo , Modelos Animais , Proteínas Proto-Oncogênicas/metabolismo , Ratos , Ratos Endogâmicos , Receptores Proteína Tirosina Quinases/metabolismo , Retina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator A de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
19.
Proc Natl Sci Counc Repub China B ; 25(4): 239-47, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11699572

RESUMO

The carbon dioxide flux density in a subtropical cultivated rice paddy field were determined over four crop seasons (two consecutive years) at five stages of rice plant development, transplanting, active tillering, booting, flowering and ripening, and an idle period between crops. During 24 h sampling periods at those stages, the CO2 flux densities were measured and found to be -2,000 to 55,000 mg CO2/m2/day in the first year and 600 to 29,000 mg CO2/m2/day in the second year in acrylic chambers covering rice plants. The CO2 flux densities in glass domes without plants but with soil were -700 to 6,000 mg CO2/m2/day in the first year and 147 to 4,500 mg CO2/m2/day in the second year. The data for the CO2 flux density over an entire year are extrapolated. Although our non-controlled environment experiments have inherent drawbacks, the collected data indicate that continuous rice cultivation has a tendency to result in increased CO2 emissions.


Assuntos
Dióxido de Carbono/análise , Oryza/crescimento & desenvolvimento , Solo/análise , Ritmo Circadiano
20.
Hum Gene Ther ; 12(10): 1299-310, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11440623

RESUMO

Pathological angiogenesis, or the production of new capillary vessels from preexisting vasculature, within the eye is a serious event that often leads to blindness. Upregulation of vascular endothelial growth factor (VEGF) has been linked to neovascularization in the eye, suggesting that it could be a suitable target to inhibit angiogenic changes. This work investigated whether the presence of a proven antiangiogenic factor, the soluble variant of the VEGF receptor, sFlt-1, in the anterior chamber is sufficient to inhibit new vessel formation in the cornea in an animal model of corneal neovascularization. A recombinant adenovirus vector that can mediate efficient in vivo gene transfer and expression in ocular cells was selected as a delivery agent. We have shown that after the injection of Ad.betagal into the anterior chamber of normal and cauterized rat eyes, corneal endothelial cells and cells of the trabecular meshwork were efficiently transduced and that beta-galactosidase (beta-Gal) expression was maintained up to 10 days postinjection. Cauterization significantly increased the amount of immunoreactive VEGF in vehicle- or Ad.null-injected animals (t test, p < 0.001 and p < 0.001, respectively). However, when cauterization was combined with Ad.sflt injection there was no statistically significant increase in the amount of immunoreactive VEGF (p = 0.12). The injection of Ad.sflt into the anterior chamber slowed or inhibited VEGF-induced angiogenic changes. After cauterization, 100% of uninjected and vehicle-injected and 82% of Ad.null-injected animals developed moderate to severe corneal angiogenesis in contrast to 18% of Ad.sflt-injected animals. These in vivo results suggest that the transient presence of antiangiogenic agents in the anterior chamber can be successfully used to inhibit the development of corneal angiogenesis.


Assuntos
Inibidores da Angiogênese/farmacologia , Córnea/irrigação sanguínea , Neovascularização da Córnea/terapia , Fatores de Crescimento Endotelial/genética , Linfocinas/genética , Neovascularização Patológica , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/biossíntese , Receptores Proteína Tirosina Quinases/genética , Adenoviridae/genética , Animais , Western Blotting , Linhagem Celular , Córnea/metabolismo , Endotélio Vascular/citologia , Olho/metabolismo , Vetores Genéticos , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Nitratos/farmacologia , Compostos de Potássio/farmacologia , Ratos , Nitrato de Prata/farmacologia , Fatores de Tempo , Transdução Genética , Transgenes , Veias Umbilicais/citologia , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular , beta-Galactosidase/metabolismo
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