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1.
Health Educ Res ; 38(5): 392-411, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37229526

RESUMO

Innovative approaches addressing the elevated human immunodeficiency virus (HIV) risk among men who have sex with men (MSM) or transgender women (TGW) migrants in South Africa are urgently needed. We sought to present the acceptability, feasibility and preliminary efficacy of 'Externalize and Mobilize!', a multi-session arts- and theatre-based HIV prevention group intervention for MSM and TGW migrants in South Africa. Fourteen participants-MSM (n = 7; 50%), genderqueer/nonbinary persons (n = 4; 29%) and TGW (n = 3; 21%)-in Cape Town were recruited and enrolled in the intervention and administered pre- and post-intervention assessments of HIV knowledge, HIV risk-reduction self-efficacy, stigma and resilience. The intervention, delivered over 4 days, was completed by all 14 participants. Scores on HIV knowledge and HIV risk-reduction self-efficacy were statistically significantly higher at post-intervention compared with pre-intervention. Additionally, participants responded affirmatively (i.e. 'Agree' or 'Strongly agree') on all items assessing intervention acceptability. Findings demonstrate the high acceptability, feasibility and preliminary efficacy of an arts- and theatre-based intervention for increasing HIV knowledge and HIV risk-reduction self-efficacy among MSM and TGW migrants in South Africa. This study provides further support for the use of creative and innovative interventions to address entrenched HIV disparities in South Africa.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Pessoas Transgênero , Migrantes , Masculino , Humanos , Feminino , Projetos Piloto , África do Sul , Homossexualidade Masculina , Estudos de Viabilidade , Infecções por HIV/prevenção & controle
2.
J Appl Microbiol ; 131(5): 2325-2335, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33797823

RESUMO

AIMS: This study aimed to clarify the cause of quality reduction in Korean sourdough after successive back-slopping. METHODS AND RESULTS: We investigated the dynamic changes in lactic acid bacteria during the back-slopping process using genetic fingerprinting techniques. During the initial propagation phases, the dominant lactic acid bacteria were Fructilactobacillus sanfranciscensis (<5 log CFU per g sourdough), Latilactobacillus curvatus (9·5 log CFU per g sourdough) and Levilactobacillus brevis (6·5 log CFU per g sourdough). However, after the 11th propagation, F. sanfranciscensis became more prominent (>9·0 log CFU per g sourdough), whereas L. curvatus and L. brevis rapidly decreased. Monitoring these bacteria in the co-culture system revealed that acid-tolerant F. sanfranciscensis rapidly utilized maltose (1·65 g l-1  h-1 ) and produced large amounts of lactic acid, whereas L. brevis and L. curvatus consumed maltose slowly and L. curvatus was poorly tolerant to lactic acid. CONCLUSION: The results indicate that competition exists between the lactic acid bacteria in sourdough during the back-slopping process, and microbial succession by acid-tolerant species results in quality reduction of sourdough. SIGNIFICANCE AND IMPACT OF THE STUDY: This study uncovered the cause of microbial changes during the propagation of Korean sourdough and proposed a strategy to develop starters to produce high-quality bakery products.


Assuntos
Lactobacillales , Pão , Fermentação , Farinha/análise , Microbiologia de Alimentos , Lactobacillales/genética , República da Coreia
3.
J Viral Hepat ; 24(3): 253-258, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27860000

RESUMO

The association between HBV infection and incident thrombocytopenia among subjects without cirrhosis or splenomegaly is unknown. Therefore, we sought to elucidate the association between HBV infection and the development of thrombocytopenia in a large cohort of apparently healthy men and women. A cohort study was performed in 122 200 participants without liver cirrhosis or splenomegaly who underwent comprehensive health examinations and were followed until December 2014. HBV infection was defined by the presence of hepatitis B surface antigen (HBsAg) at baseline. Thrombocytopenia was defined as a platelet count <150 000/µL. Cox proportional hazard models were used to estimate adjusted hazard ratios with 95% confidence intervals (CIs) for incident thrombocytopenia. HBsAg was positive in 4857 of 122 200 subjects (4.0%) at baseline. During 883 983 person-years of follow-up, 2037 incident cases of thrombocytopenia were identified (incident rate 2.3 per 1000 person-years). HBsAg-positive subjects had a higher incidence of thrombocytopenia than did healthy controls (11.2 vs 1.9 per 1000 person-years, respectively). The multivariate-adjusted hazard ratio (95% CI) for incident thrombocytopenia comparing HBsAg-positive to HBsAg-negative subjects was 5.71 (5.10-6.38). Strong associations between HBsAg positivity and thrombocytopenia were consistently observed across prespecified subgroups. In this large cohort study of an apparently healthy population, HBsAg positivity was strongly and independently associated with incident thrombocytopenia, indicating that mechanisms of thrombocytopenia other than portal hypertension may exist in healthy HBV carriers.


Assuntos
Hepatite B/complicações , Trombocitopenia/epidemiologia , Adulto , Estudos de Coortes , Feminino , Antígenos de Superfície da Hepatite B/sangue , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas
4.
Acta Virol ; 61(1): 105-115, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28161965

RESUMO

3D8 scFv, a catalytic recombinant antibody developed in the MRL mouse, exhibits nucleic acid-hydrolyzing activity. Previous studies have demonstrated that tobacco plants harboring 3D8 scFv antibodies showed broad-spectrum resistance to infection by both DNA and RNA viruses. In this study, potatoes were transformed with the 3D8 scFv gene and screened by potato virus X (PVX) challenge. Starting with the T0 and T1 potato lines, PVX-tolerant T1 potatoes were identified in the field and characterized by ELISA and RT-PCR analysis. T2 potatoes were propagated for T3 generation and additional virus challenges in the field, and 44% of the 3D8 scFv T3 transgenic potatoes grown in GMO fields were found to be tolerant to PVX infection. Tubers from PVX-tolerant T3 lines were 60% bigger and 24% heavier, compared with tubers from PVX-susceptible transgenic lines and wild-type potatoes. Three-step virus challenge experiments and molecular characterization techniques were used for plants grown in growth chambers or fields to identify 3D8 scFv-transgenic, PVX-tolerant potatoes. These studies also revealed that the viral tolerance enabled by 3D8 scFv persisted during asexual propagation.


Assuntos
Doenças das Plantas/virologia , Solanum tuberosum/genética , Solanum tuberosum/virologia , Anticorpos Antivirais , Predisposição Genética para Doença , Doenças das Plantas/genética , Plantas Geneticamente Modificadas , Potyvirus , Proteínas Recombinantes , Transformação Genética
5.
Spinal Cord ; 49(2): 236-43, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20856260

RESUMO

STUDY DESIGN: Case-control study. OBJECTIVES: To investigate changes of biomechanical skin properties and their relationship with paralysis following spinal cord injury (SCI). SETTING: South Korea. METHODS: A total of 48 male subjects with chronic SCI and 48 age-matched healthy controls were enrolled into this study. The C4 shoulder group and L2 thigh group were prescribed by two measured anatomical regions that represented the C4 and L2 American Spinal Injury Association sensory dermatomes. Each anatomical group was comprised of one control subgroup and three SCI subgroups determined by sympathetic paralysis at the measured region and somatic completeness. The following biomechanical skin properties were compared between the subgroups in each anatomical group by using Cutometer, a non-invasive suction device: distensibility (Uf), elasticity (Ua/Uf and Ur/Uf) and viscoelasticity (Uv/Ue and H). The impact of sympathetic and somatic sensory paralysis, somatic completeness, age, smoking, body mass index and duration of injury on the indices of skin properties were analyzed. RESULTS: In each anatomical group, sympathetic paralyzed subgroups regardless of somatic sensory completeness showed lower value of skin distensibility (Uf), and higher values of elasticity (Ua/Uf and Ur/Uf) and viscoelasticity (Uv/Ue and H), compared with other subgroups. Age and duration of injury had significant impact on biomechanical skin properties. CONCLUSION: The non-invasive suction method is useful for quantitative evaluation of skin affected by SCI. In chronic SCI patients, biomechanical skin properties are significantly altered in the skin with sympathetic paralysis rather than somatic sensory paralysis.


Assuntos
Doenças do Sistema Nervoso Autônomo/fisiopatologia , Pele/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , Adulto , Idoso , Doenças do Sistema Nervoso Autônomo/diagnóstico , Doenças do Sistema Nervoso Autônomo/etiologia , Fenômenos Biomecânicos/fisiologia , Estudos de Casos e Controles , Humanos , Masculino , Pessoa de Meia-Idade , Pele/inervação , Traumatismos da Medula Espinal/complicações , Adulto Jovem
6.
ESMO Open ; 6(6): 100309, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34844180

RESUMO

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of squamous cell carcinoma (SCC) of the oral cavity, larynx, oropharynx and hypopharynx was published in 2020. It was therefore decided by both the ESMO and the Korean Society of Medical Oncology (KSMO) to convene a special, virtual guidelines meeting in July 2021 to adapt the ESMO 2020 guidelines to consider the potential ethnic differences associated with the treatment of SCCs of the head and neck (SCCHN) in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with SCCHN (excluding nasopharyngeal carcinomas) representing the oncological societies of Korea (KSMO), China (CSCO), India (ISMPO), Japan (JSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug access restrictions in the different Asian countries. The latter was discussed when appropriate. This manuscript provides a series of expert recommendations (Clinical Practice Guidelines) which can be used to provide guidance to health care providers and clinicians for the optimisation of the diagnosis, treatment and management of patients with SCC of the oral cavity, larynx, oropharynx and hypopharynx across Asia.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/terapia , Seguimentos , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Oncologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia
7.
Cryo Letters ; 30(4): 291-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19789826

RESUMO

In plant vitrification protocols, the loading treatment, which involves treating the explants with a moderately concentrated cryoprotectant solution, precedes dehydration of explants with highly concentrated vitrification solutions in order to reduce the toxicity which can be induced by their direct exposure to such highly concentrated solutions. This study aimed at developing alternative loading solutions composed of mixtures of glycerol and sucrose at various concentrations. Differential scanning calorimetry runs of loading solutions and of loaded and dehydrated explants were performed to assay thermal events occurring during cooling and warming. These loading solutions were applied to two model species, viz. garlic and chrysanthemum which were cryopreserved using a droplet-vitrification procedure. The loading treatment proved to be beneficial to both garlic and chrysanthemum and increased recovery of cryopreserved explants. However, response to the loading solutions tested varied between the two model species employed: with garlic, all the loading solutions had a similar effect, whereas survival of chrysanthemum shoot tips was significantly influenced by the composition of the loading solution employed. A loading solution comprising 1.9 M glycerol and 0.5 M sucrose was the most effective. The loading treatment may thus act as an osmotic stress neutralizer and/or induce the physiological adaptation of tissues and cells, including membranes, to both dehydration and freezing.


Assuntos
Criopreservação/métodos , Crioprotetores/farmacologia , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/fisiologia , Chrysanthemum , Alho , Glicerol/farmacologia , Sacarose/farmacologia
8.
Br J Pharmacol ; 154(4): 852-63, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18454171

RESUMO

BACKGROUND AND PURPOSE: Mushrooms are popular both as food and as a source of natural compounds of biopharmaceutical interest. Some mushroom-derived compounds such as beta-glucan have been shown to be immunostimulatory; this study explores the anti-inflammatory properties of hispidin analogues derived from the mushroom, Inonotus xeranticus. We sought to identify the molecular mechanism of action of these hispidin analogues by determining their effects on lipopolysaccharide (LPS)-mediated inflammatory responses in a macrophage cell line. EXPERIMENTAL APPROACH: The production of inflammatory mediators was determined by Griess assay, reverse transcription-PCR and ELISA. The inhibitory effect of davalliactone on LPS-induced activation of signalling cascades was assessed by western blotting, immunoprecipitation and direct kinase assay. KEY RESULTS: In activated RAW264.7 cells, davallialactone strongly downregulated LPS-mediated inflammatory responses, including NO production, prostaglandin E2 release, expression of proinflammatory cytokine genes and cell surface expression of co-stimulatory molecules. Davallialactone treatment did not alter cell viability or morphology. Davallialactone was found to exert its anti-inflammatory effects by inhibiting a signalling cascade that activates nuclear factor kappa B via PI3K, Akt and IKK, but not mitogen-activated protein kinases. Treatment with davallialactone affected the phosphorylation of these signalling proteins, but not their level of expression. These inhibitory effects were not due to the interruption of toll-like receptor 4 binding to CD14. In particular, davallialactone strongly inhibited the LPS-induced phosphorylation and kinase activity of Src, implying that Src may be a potential pharmacological target of davallialactone. CONCLUSIONS AND IMPLICATIONS: Our data suggest that davallialactone, a small molecule found in edible mushrooms, has anti-inflammatory activity. Davallialactone can be developed as a pharmaceutically valuable anti-Src kinase agent.


Assuntos
Anti-Inflamatórios/farmacologia , Inflamação/tratamento farmacológico , Lactonas/farmacologia , Quinases da Família src/antagonistas & inibidores , Agaricales/química , Animais , Anti-Inflamatórios/isolamento & purificação , Linhagem Celular , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Inflamação/fisiopatologia , Lactonas/isolamento & purificação , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Fosforilação/efeitos dos fármacos , Receptores de Reconhecimento de Padrão/efeitos dos fármacos , Receptores de Reconhecimento de Padrão/metabolismo , Transdução de Sinais/efeitos dos fármacos , Quinases da Família src/metabolismo
9.
Water Sci Technol ; 55(1-2): 367-74, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17305161

RESUMO

This paper delivers two issues: water quality in the Yeongsan (YS) watershed which is one of the major watersheds in Korea and new watershed management plans with respect to the total maximum daily loads (TMDL) management. Field studies were conducted to estimate the pollutant loads according to the spatial and temporal distribution based on the biochemical oxygen demand (BOD) concentration and the volumetric flow rate (VFR) data from YS watershed. The results of both spatial and temporal analyses show the main pollutant source was originated from the city of Gwangju and the pollutant load from the city to YS watershed was the most out of five cities during this study period. Concerning YS reservoir located downstream of YS watershed, it also shows the worst water quality in the entire watershed during the study period. These results collectively demonstrate that the city of Gwangju is a main region which generates numerous point and non-point pollutant sources and eventually the pollutants are accumulated in YS reservoir. Based on the results, we suggest two different management plans for YS watershed. One is the flow-control approach that is to increase the amount of dam discharge in order to guarantee the river management flow for the midstream region. The other is the mass-control approach that is to dredge the contaminated sediments in YS reservoir for removing pollutants chronically accumulated in the sediment. Simulations for the former and the latter provide the pollution mitigation rate in the watershed up to 6 and 8% for BOD5, respectively. The methodology proposed here for TMDL management can be applied to a wide range of watersheds in Korea.


Assuntos
Poluentes da Água/análise , Poluição da Água/prevenção & controle , Abastecimento de Água/análise , Monitoramento Ambiental , Coreia (Geográfico)
10.
Proc Math Phys Eng Sci ; 471(2179): 20140827, 2015 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-26345141

RESUMO

This paper presents a closed-form solution for the arbitrary polygonal inclusion problem with polynomial eigenstrains of arbitrary order in an anisotropic magneto-electro-elastic full plane. The additional displacements or eigendisplacements, instead of the eigenstrains, are assumed to be a polynomial with general terms of order M+N. By virtue of the extended Stroh formulism, the induced fields are expressed in terms of a group of basic functions which involve boundary integrals of the inclusion domain. For the special case of polygonal inclusions, the boundary integrals are carried out explicitly, and their averages over the inclusion are also obtained. The induced fields under quadratic eigenstrains are mostly analysed in terms of figures and tables, as well as those under the linear and cubic eigenstrains. The connection between the present solution and the solution via the Green's function method is established and numerically verified. The singularity at the vertices of the arbitrary polygon is further analysed via the basic functions. The general solution and the numerical results for the constant, linear, quadratic and cubic eigenstrains presented in this paper enable us to investigate the features of the inclusion and inhomogeneity problem concerning polynomial eigenstrains in semiconductors and advanced composites, while the results can further serve as benchmarks for future analyses of Eshelby's inclusion problem.

11.
Free Radic Res ; 49(1): 25-34, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25287330

RESUMO

The production of microRNAs (miRNA) is influenced by various stimuli, including environmental stresses. We hypothesized that reactive oxygen species (ROS)-associated stress could regulate macrophage miRNA synthesis. miRNAs undergo unique steps of maturation processing through either one of two pathways of cytoplasmic processing. Unlike the canonical pathway, the regulation of alternative cytoplasmic processing of miRNA has not been fully elucidated yet. We cultured bone marrow derived macrophages (BMDM) from wild type (WT) and p47(phox-/-) mice and profiled miRNA expression using microarrays. We analyzed 375 miRNAs including four endogenous controls to normalize the data. At resting state, p47(phox-/-) BMDM has the markedly reduced expression of miR-451 compared to WT BMDM, without other significant differences. Unlike majority of miRNAs, miR-451 goes through the unique alternative processing pathway, in which Ago2 plays a key role. In spite of significant reduction of mature miR-451, however, its precursor form, pre-mir-451, was similar in both BMDMs, suggesting that the processing of pre-mir-451 is impaired in p47(phox-/-) BMDM. Moreover, p47(phox-/-) BMDM expressed significantly reduced level of Ago2. In contrast, Ago2 mRNA levels were similar in WT and p47(phox-/-) BMDM, suggesting a post-transcriptional defect of Ago2 production in p47(phox-/-) macrophages, which resulted in impaired processing of pre-miR-451. In order to examine the functional significance of miR-451 in macrophages, we cultured BMDMs from miR-451 knock-out mice. Of interest, miR-451-deficient BMDM exhibited reduced ROS generation upon zymosan stimulation, compared to WT BMDM. Our studies suggest functional crosstalk between ROS and miR-451 in the regulation of macrophage oxidant stress.


Assuntos
Macrófagos/metabolismo , MicroRNAs/biossíntese , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Proteínas Argonautas/metabolismo , Linhagem Celular , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , MicroRNAs/metabolismo , NADPH Oxidases/deficiência , NADPH Oxidases/genética
12.
Invest Ophthalmol Vis Sci ; 37(11): 2326-34, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8843917

RESUMO

PURPOSE: Fibroblast growth factor 2 (FGF-2) is not only a potent mitogen, it is a modulator for corneal endothelial cells. To define how the modulation activities of FGF-2 are mediated, we used pharmacologic inhibitors to examine the association of phospholipase C-gamma 1 (PLC-gamma) with FGF receptor or with cytoskeleton. METHODS: Cell proliferation was determined either by the incorporation of 3H-thymidine into DNA or by counting cell numbers in the absence or presence of the inhibitors. The protein expression was analyzed by immunoprecipitation and immunoblot analysis. Cell shape change was determined by phase-contrast microscopy. RESULTS: FGF-2 stimulated DNA synthesis, whereas genistein inhibited the FGF-2-mediated cell proliferation in a dose-dependent manner, regardless of the concentration of FGF-2. The PLC-gamma 1 specific antisense oligonucleotide primer was able to inhibit cell proliferation by 25% in the absence of FGF-2; however, the antisense primer was not able to override the action of FGF-2. Fibroblast growth factor receptor was phosphorylated on treatment of the cells with FGF-2; however, 24-hour treatment with the growth factor significantly reduced phosphorylation of the receptor. Phospholipase C gamma 1 appears to be abundant in cytoplasm in the absence and presence of FGF-2, and a minor portion of the molecule is translocated to membrane after treatment with FGF-2; genistein inhibited the translocation. When the cytoskeleton fraction of the normal and the modulated corneal endothelial cells was immunoprecipitated with PLC-gamma 1 antibodies, PLC-gamma 1, actin, and vinculin were coprecipitated in both cell cultures. Phospholipase C gamma 1 associated with cytoskeleton was phosphorylated on treatment of the cells with FGF-2. In the presence of FGF-2 of the modulated cells, cytochalasin B, which did not revert the modulated cell morphology, abolished the association of PLC-gamma 1 with actin and vinculin; colchicine, which did revert the modulated cell shape to the polygonal shape, did not block the association of these three molecules. Interestingly, colchicine slightly enhanced the stimulatory effect of FGF-2 on corneal endothelial proliferation in contrast to the effect of cytochalasin B, which slightly decreased the FGF-2 action on cell proliferation. CONCLUSIONS: The association of PLC-gamma 1 with cytoskeleton plays a role in cell proliferation, whereas the association of PLC-gamma 1 with actin and vinculin has no effect on cell shape changes. These findings indicate that FGF-2 appears to use distinct signaling pathways for cell proliferation and cell shape changes in corneal endothelial cells.


Assuntos
Endotélio Corneano/fisiologia , Fator 2 de Crescimento de Fibroblastos/fisiologia , Transdução de Sinais , Animais , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Tamanho Celular/efeitos dos fármacos , Tamanho Celular/fisiologia , Células Cultivadas , DNA/biossíntese , Replicação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Endotélio Corneano/citologia , Fator 2 de Crescimento de Fibroblastos/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Genisteína , Inibidores do Crescimento/farmacologia , Isoenzimas/metabolismo , Isoflavonas/farmacologia , Fosfolipase C gama , Coelhos , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Fosfolipases Tipo C/metabolismo
13.
Free Radic Res ; 30(6): 499-507, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10400462

RESUMO

Alteration of free radical metabolism in the mouse brain by scrapie infection was evaluated. The infection of mice with scrapie agent, 87V strain, slightly increased the activities of catalase and glutathione-S-transferase, while it had no effect on glutathione peroxidase, glutathione reductase, and Cu, Zn-superoxide dismutase. Results show that the scrapie infection decreased the activity of mitochondrial Mn-superoxide dismutase by 50% but increased that of monoamine oxidase (p < 0.05). Scrapie infection also increased the rate of mitochondrial superoxide generation (p < 0.05). Following scrapie infection, the level of free-sulfhydryl compounds in brain homogenates slightly decreased, but the content of thiobarbituric-acid-reactive substances and malondialdehyde increased significantly. Electron microscopy indicated that the ultrastructure of mitochondria was destroyed in the brain of scrapie-infected mice. These results suggest that elevated oxygen free radical generation and lowered scavenging activity in mitochondria might cause the free radical damage to the brain. Such deleterious changes in mitochondria may contribute to the development of prion disease.


Assuntos
Encéfalo/metabolismo , Radicais Livres/metabolismo , Scrapie/metabolismo , Animais , Antioxidantes/metabolismo , Encéfalo/enzimologia , Encéfalo/patologia , Química Encefálica , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Masculino , Malondialdeído/análise , Camundongos , Mitocôndrias/enzimologia , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Mitocôndrias/ultraestrutura , Monoaminoxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Compostos de Sulfidrila/análise , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/análise
14.
J Refract Surg ; 16(4): 467-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10939728

RESUMO

PURPOSE: Nocardia are gram-positive bacteria existing ubiquitously in the environment; they can cause keratitis. Nocardia asteroides keratitis occurred in the interface between the stromal bed and flap after traumatic detachment of the flap 4 months after an initially uncomplicated laser in situ keratomileusis (LASIK) procedure. METHODS: Nocardia asteroides keratitis was confirmed by culture. Therapy included topical and oral trimethoprim-sulfamethoxazole. RESULTS: Thirteen months after the trauma, the patient's spectacle-corrected visual acuity was 20/20 with a manifest refraction of -2.25 -1.00 x 30 degrees. CONCLUSIONS: The immediate steps of management consisting of surgically lifting the corneal flap, rapid microbial identification, and proper treatment with specific antibiotics resulted in the successful treatment of Nocardia asteroides keratitis in a traumatized eye after LASIK.


Assuntos
Lesões da Córnea , Infecções Oculares Bacterianas , Traumatismos Oculares/microbiologia , Ceratite/microbiologia , Ceratomileuse Assistida por Excimer Laser In Situ , Nocardiose/microbiologia , Retalhos Cirúrgicos/microbiologia , Adulto , Antibacterianos/administração & dosagem , Córnea/microbiologia , Córnea/cirurgia , Quimioterapia Combinada , Infecções Oculares Bacterianas/tratamento farmacológico , Infecções Oculares Bacterianas/microbiologia , Humanos , Ceratite/tratamento farmacológico , Masculino , Nocardiose/tratamento farmacológico , Nocardia asteroides/isolamento & purificação , Soluções Oftálmicas , Sulfametoxazol/administração & dosagem , Trimetoprima/administração & dosagem , Acuidade Visual , Ferimentos não Penetrantes/complicações
15.
J Cataract Refract Surg ; 27(4): 565-70, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11311625

RESUMO

PURPOSE: To compare the effectiveness, safety, and stability of laser epithelial keratomileusis (LASEK), a modified photorefractive keratectomy (PRK) technique, with those of conventional PRK for low to moderate myopia. SETTING: Department of Ophthalmology, Yonsei University School of Medicine, Seoul, Korea. METHODS: In this prospective study, 27 patients with a manifest refraction of -3.00 to -6.50 diopters were treated and followed for 3 months. In each case, PRK was performed in 1 eye and LASEK in the other eye. The first eye treated and the surgical method used in the first eye were randomized. Postoperative pain, epithelial healing time, uncorrected visual acuity (UCVA), manifest refraction, corneal haze, and surgical preference were examined in PRK- and LASEK-treated eyes. RESULTS: During the 3 month follow-up, there were no significant between-eye differences in epithelial healing time, UCVA, or refractive error. However, LASEK-treated eyes had lower postoperative pain scores (P =.047) and corneal haze scores (1 month; P =.02) than PRK-treated eyes. Seventeen patients (63%) preferred the LASEK procedure. CONCLUSIONS: Laser epithelial keratomileusis safely and effectively treated eyes with low to moderate myopia. It reduced the incidence of significant postoperative pain and corneal haze and may prevent the flap- and interface-related problems of laser in situ keratomileusis.


Assuntos
Córnea/cirurgia , Ceratomileuse Assistida por Excimer Laser In Situ , Miopia/cirurgia , Ceratectomia Fotorrefrativa , Adulto , Feminino , Seguimentos , Humanos , Lasers de Excimer , Masculino , Dor Pós-Operatória/prevenção & controle , Estudos Prospectivos , Refração Ocular , Segurança , Resultado do Tratamento , Acuidade Visual , Cicatrização
16.
Life Sci ; 66(4): 317-26, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10665983

RESUMO

We examined the effects of cigarette smoke (CS) on three parameters associated with kainic acid (KA)-induced neurotoxicity: seizure activity, cell loss in the hippocampus, and increased Fos-related antigen (FRA) expression. Animals were exposed to the main stream of CS from 15 Kentucky 2R1F research cigarettes containing 28.6 mg tar and 1.74 mg nicotine per cigarette, for 10 min a day, 6 days per week, for 4 weeks, using an automatic smoking machine. KA administration (10 mg/kg, i.p.) produced robust behavioral convulsions lasting 4-5 h. Pre-exposure to CS significantly reduced the seizures, mortality, and severe loss of cells in regions CA1 and CA3 of the hippocampus after KA administration. Consistently, pre-exposure to CS significantly attenuated the KA-induced increased FRA immunoreactivity in the hippocampus. In contrast, pretreatment with central nicotinic antagonist, mecamylamine (2 or 10 mg/kg, i.p.) blocked the neuroprotective effects mediated by CS in a dose-dependent manner. These results indicate that CS exposure provides neuroprotection against the KA insult via nicotinic receptor activation.


Assuntos
Encéfalo/efeitos dos fármacos , Ácido Caínico/toxicidade , Fármacos Neuroprotetores/farmacologia , Nicotiana , Plantas Tóxicas , Fumaça , Animais , Sítios de Ligação , Masculino , Mecamilamina/farmacologia , Nicotina/farmacologia , Proteínas Proto-Oncogênicas c-fos/análise , Proteínas Proto-Oncogênicas c-fos/imunologia , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/fisiologia , Receptores Nicotínicos/fisiologia
17.
Curr Eye Res ; 17(3): 286-93, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9543637

RESUMO

PURPOSE: Although transforming growth factor-betas (TGF-beta s) inhibit epithelial cell proliferation, these same substances stimulate cell proliferation of fibroblasts. In order to elucidate the mechanism of stimulatory activity of TGF-beta on fibroblast, the present study was performed to determine whether TGF-beta might be an indirect mitogen acting through induction of an endogenous growth factor(s) that then acts as the direct mitogen in an autocrine manner in corneal stromal fibroblasts (CSFs). METHODS: Cell proliferation was determined either by counting cell numbers or by analyzing the incorporation of [3H]-thymidine into DNA. The synthesis of TGF-beta, TGF-beta receptors, FGF-2 and p27 was analyzed by immunoprecipitation and immunoblotting. RESULTS: TGF-beta 1, TGF-beta 2, and TGF-beta 3 significantly stimulated cell proliferation of CSFs in a dose-dependent manner. The medium conditioned by CSFs and subsequently activated by acid-inhibited cell proliferation of corneal endothelial cells by 40%. When the acid-activated media conditioned by CSFs were immunoprecipitated with either combined anti-TGF-beta 1 and TGF-beta 2 antibodies or anti-TGF-beta 3 antibody, all three TGF-beta s, with an apparent molecular size of 25 kDa, were detected, whereas CSFs produced an 80-kDa latent form of TGF-beta 1. These cells can also express TGF-beta type II receptor and betaglycan. Interestingly, CSFs produced and secreted 18-kDa FGF-2, the synthesis of which is further stimulated by either TGF-beta 1 or TGF-beta 3, while both the neutralizing antibody to FGF-2 and the FGF-2 specific antisense oligonucleotide primers significantly inhibited the stimulatory activities of TGF-beta 1 in CSFs. The expression of p27, a negative regulator in cell cycle, was not altered by TGF-beta. CONCLUSIONS: These findings indicate that CSFs produce both TGF-beta s and FGF-2 and that FGF-2 appears to be a direct stimulator for TGF-beta-mediated cell proliferation in CSFs.


Assuntos
Proteínas de Ciclo Celular , Substância Própria/citologia , Fator 2 de Crescimento de Fibroblastos/biossíntese , Fator de Crescimento Transformador beta/farmacologia , Proteínas Supressoras de Tumor , Animais , Contagem de Células , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Substância Própria/efeitos dos fármacos , Substância Própria/metabolismo , Inibidor de Quinase Dependente de Ciclina p27 , Replicação do DNA , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Técnicas Imunoenzimáticas , Proteínas Associadas aos Microtúbulos/biossíntese , Oligonucleotídeos Antissenso/química , Coelhos , Receptores de Fatores de Crescimento Transformadores beta/biossíntese , Fator de Crescimento Transformador beta/biossíntese , Regulação para Cima
18.
In Vivo ; 15(2): 157-62, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11317521

RESUMO

BACKGROUND: The lack of appropriate, clinically relevant, cell-based model systems has limited prostate cancer research and the development of new therapeutic modalities. Here we report the isolation and characterization of a new adherent prostate cancer cell line, derived from the dura mater of a cancer patient. METHODS: Prostate cancer tissue was harvested at autopsy from a metastatic lesion to the dura mater of a patient with hormone refractory prostate cancer. This tissue was xenografted into SCID mice and later harvested and plated on tissue culture dishes. For characterization, soft agar clonegenic assay, in vivo xenograft growth, in vitro doubling time, karyotype analysis, immunocytochemistry for cytokeratin-18, androgen receptor, and PAP (prostatic acid phosphatase) expression, RT PCR for PAP, PSMA (prostate specific membrane antigen), expression and northern and western blot analysis to determine expression of Rb and p53, were performed. RESULTS: DuCap grows in vitro (passage 55), forms colonies in soft agar, produces tumors in SCID mice (xenograft passage 12), and is androgen sensitive. DNA content was hypertriploid. PSA was detected in mouse serum and media. Cells were AR, PAP and cytokeratin-18 positive by immunocytochemistry. PSMA and PAP were detected by RT-PCR. AR, P53, and Rb were expressed in Northern blot analysis. P53 protein was detected in Western blot analysis but Rb protein was not. CONCLUSIONS: This cell line exhibits many phenotypic characteristics of clinical prostate carcinoma, including expression of PSA, PSMA, PAP and AR.


Assuntos
Técnicas de Cultura de Células/métodos , Células Epiteliais/citologia , Neoplasias da Próstata/patologia , Células Tumorais Cultivadas/citologia , Androgênios/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Dura-Máter , Feminino , Citometria de Fluxo , Humanos , Cariotipagem , Masculino , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/secundário , Camundongos , Camundongos SCID , Pessoa de Meia-Idade , Transplante de Neoplasias , Neoplasias da Próstata/genética , RNA Mensageiro/análise , Proteína do Retinoblastoma/genética , Células Tumorais Cultivadas/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética
19.
In Vivo ; 15(2): 163-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11317522

RESUMO

OBJECTIVES: We report the isolation and characterization of a novel prostate cancer cell line derived from a vertebral metastatic lesion, Vertebral-Cancer of the Prostate (VCaP). METHODS: Prostate cancer tissue was harvested at autopsy from a metastatic lesion to a lumbar vertebral body of a patient with hormone refractory prostate cancer. This tissue was aseptically xenografted into SCID mice and later harvested and plated on tissue culture dishes. For characterization, soft agar clonegenic assay, in vivo xenograft growth, in vitro doubling time, karyotype analysis, immunocytochemistry for cytokeratin-18 expression immunochemistry for PSA (prostate specific antigen), RT PCR for PAP (prostatic acid phosphatase) and northern blot and western blot analysis to determine expression of Rb and p53, were performed. Androgen receptor expression was measured by transient transfection with a luciferase reporter construct. RESULTS: VCaP cells are immortal in vitro and can be passaged serially in vivo. They express large quantities of prostate specific antigen (PSA). This cell line also expresses prostatic acid phosphatase (PAP), cytokeratin-18 and the androgen receptor, and is androgen sensitive in vitro and in vivo. CONCLUSIONS: This cell line was derived from a metastatic tumor to the vertebrae of a prostate cancer patient. It exhibits many of the characteristics of clinical prostate carcinoma, including expression of PSA, PAP, and AR. We believe that VCaP will be a useful addition to the existing models of prostate cancer, and enable more advanced study of the mechanisms of prostate cancer progression and metastasis.


Assuntos
Técnicas de Cultura de Células/métodos , Neoplasias da Próstata/patologia , Neoplasias da Coluna Vertebral/secundário , Células Tumorais Cultivadas/citologia , Fosfatase Ácida , Animais , Divisão Celular , Células Epiteliais/química , Células Epiteliais/citologia , Feminino , Humanos , Cariotipagem , Queratinas/análise , Masculino , Camundongos , Camundongos SCID , Pessoa de Meia-Idade , Antígeno Prostático Específico/análise , Neoplasias da Próstata/genética , Proteínas Tirosina Fosfatases/análise , RNA Mensageiro/análise , Receptores Androgênicos/genética , Neoplasias da Coluna Vertebral/genética
20.
Yonsei Med J ; 41(2): 185-9, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10817017

RESUMO

The proliferation of residual lens epithelial cells following cataract surgery is assumed to be a major cause of posterior capsular opacification. To assess the efficacy of mitomycin-C in preventing posterior capsular opacification, we determined the effective concentration and exposure time of mitomycin-C in inhibiting rabbit lens epithelial cell proliferation. The fourth-passaged rabbit lens epithelial cells were maintained for one day and then exposed to mitomycin-C for 1, 2, 3, and 5 minutes, respectively. There were 9 different plating concentrations of mitomycin-C with two-fold serial dilution. The maintenance of the phenotypic properties of lens epithelial cells was confirmed by continuous transcription of lambda-crystalline mRNA determined by reverse transcription-polymerase chain reaction and the polymorphism of the restriction fragment. Cell proliferation was assayed with 3H-thymidine incorporation into DNA. The fourth-passaged cells maintained the expression of lambda-crystalline mRNA, suggesting that they are phenotypically authentic lens epithelial cells. The effective concentrations and exposure time of mitomycin-C were 0.1 mg/ml for 1 minute and 2 minutes, and 0.025 mg/ml for 2 minutes. By these results, we postulated that mitomycin-C at relatively short incubation times could be clinically used for prevention of posterior capsular opacification after cataract surgery.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Cristalino/efeitos dos fármacos , Mitomicina/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Células Cultivadas , DNA/biossíntese , Relação Dose-Resposta a Droga , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Cristalino/citologia , Coelhos , Fatores de Tempo
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