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1.
J Biol Chem ; 300(3): 105669, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272221

RESUMO

The mitotic spindle contains many bundles of microtubules (MTs) including midzones and kinetochore fibers, but little is known about how bundled structures are formed. Here, we show that the chromosomal passenger complex (CPC) purified from Escherichia coli undergoes liquid-liquid demixing in vitro. An emergent property of the resultant condensates is to generate parallel MT bundles when incubated with free tubulin and GTP in vitro. We demonstrate that MT bundles emerge from CPC droplets with protruding minus ends that then grow into long and tapered MT structures. During this growth, we found that the CPC in these condensates apparently reorganize to coat and bundle the resulting MT structures. CPC mutants attenuated for liquid-liquid demixing or MT binding prevented the generation of parallel MT bundles in vitro and reduced the number of MTs present at spindle midzones in HeLa cells. Our data demonstrate that an in vitro biochemical activity to produce MT bundles emerges after the concentration of the CPC and provides models for how cells generate parallel-bundled MT structures that are important for the assembly of the mitotic spindle. Moreover, these data suggest that cells contain MT-organizing centers that generate MT bundles that emerge with the opposite polarity from centrosomes.


Assuntos
Cromossomos , Microtúbulos , Fuso Acromático , Humanos , Células HeLa , Cinetocoros/metabolismo , Microtúbulos/metabolismo , Mitose , Fuso Acromático/metabolismo , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Animais , Xenopus laevis
2.
J Am Chem Soc ; 145(1): 345-358, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36535642

RESUMO

Hypervalent chloranes are a class of rare and poorly explored reagents. Their unique electronic properties confer reactivity that is complementary to that of the common iodanes and emerging bromanes. Highly chemo- and regioselective, metal-free, and mild C-C and C-O couplings are reported here. Experimental and computational mechanistic studies elucidate the unprecedented reactivities and selectivities of these systems and the intermediacy of aryne intermediates. The synthetic potential of these transformations is further demonstrated via the post-functionalization of C-C and C-O coupling products obtained from reactions of chloranes with phenols under different conditions.


Assuntos
Fenóis , Indicadores e Reagentes
3.
Optom Vis Sci ; 97(9): 676-682, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32932396

RESUMO

SIGNIFICANCE: This study evaluated the effects scleral lens wear has on corneal health using fluorometry and in vivo confocal microscopy. No subclinical changes on healthy corneas of young subjects were observed during 3 months of scleral lens wear. PURPOSE: This study aimed to evaluate the effects 3 months of scleral lens wear has on the corneal epithelial barrier function, dendritic cell density, and nerve fiber morphology. METHODS: Twenty-seven neophytes (mean [standard deviation] age, 21.4 [3.9] years) wore scleral lenses of a fluorosilicone acrylate material bilaterally (97 Dk, 15.6 to 16.0-mm diameter) for 3 months without overnight wear. Subjects were randomized to use either Addipak (n = 12) or PuriLens Plus (n = 15) during lens insertion. Measurements of corneal epithelial permeability to fluorescein were performed with automated scanning fluorophotometer (Fluorotron Master; Ocumetrics, Mountain View, CA) on the central cornea of the right eye and the temporal corneal periphery of the left eye. Images of the distributions of corneal nerve fibers and dendritic cells and nerve fibers were captured in vivo with a confocal laser scanning microscope (Heidelberg Retina Tomograph, Rostock Cornea Module; Heidelberg Engineering, Heidelberg, Germany) on the central and inferior peripheral cornea of the left eye. Corneal measurements and imaging were performed at baseline and after 1 and 3 months of lens wear. RESULTS: The corneal permeability values in natural log, dendritic cell densities, and nerve fiber morphology did not significantly change from baseline to 1 and 3 months of lens wear, for both central and peripheral corneal regions (P > .05). Dendritic cell density at the inferior cornea was higher than the central cornea throughout the study (P < .001). No relationships were observed between each outcome measurements and the saline solution groups (P > .05). CONCLUSIONS: Scleral lens wear for 3 months on healthy cornea of young subjects did not affect corneal epithelial barrier function, nerve fiber, and dendritic cell densities. Buffered and nonbuffered saline solutions impacted the corneal health in similar ways.


Assuntos
Lentes de Contato , Córnea/fisiologia , Esclera , Contagem de Células , Córnea/inervação , Células Dendríticas/citologia , Método Duplo-Cego , Epitélio Corneano/fisiologia , Feminino , Fluorofotometria , Humanos , Masculino , Microscopia Confocal , Nervo Oftálmico/anatomia & histologia , Estudos Prospectivos , Fatores de Tempo , Adulto Jovem
4.
Clin Exp Ophthalmol ; 48(5): 569-579, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32100917

RESUMO

IMPORTANCE: Atropine eyedrops are a promising treatment for slowing myopia progression in East Asian children. However, its effects on children in Australia, including those of non-Asian background, have not been well-studied. BACKGROUND: The Western Australia Atropine for the Treatment of Myopia (WA-ATOM) study aims to determine the efficacy and long-term effects of low-dose atropine eyedrops in myopia control. This paper describes the study rationale, methodology and participant baseline characteristics. DESIGN: Single-centre, double-masked, randomized controlled trial. PARTICIPANTS: Children (6-16 years) with spherical equivalent ≤-1.50 D in each eye, astigmatism ≤1.50 D and myopia progression by ≥0.50 D/year. METHODS: Enrolled children were randomly assigned 2:1 to receive 0.01% atropine or placebo eyedrops. Participants are examined every 6 months during first 3 years of the study (2-year treatment phase followed by a 1-year washout phase), and then at a 5-year follow-up (2 years after the end of the washout phase). MAIN OUTCOME MEASURES: Annual progression rate of myopia and axial length, tolerability to eyedrops and incidence and severity of unwanted effects. RESULTS: Out of 311 children who were referred, 242 were suitable for study participation, and 153 were subsequently enrolled. The baseline characteristics of enrolled participants are presented. CONCLUSIONS AND RELEVANCE: Outcomes of the WA-ATOM study will inform on the efficacy, tolerability, safety and long-term effects of low-dose atropine eyedrops in myopia control in Australian children. The impact of ocular sun exposure, iris colour and parental myopia on the efficacy of low-dose atropine will also be assessed.


Assuntos
Atropina , Miopia , Austrália/epidemiologia , Criança , Progressão da Doença , Humanos , Miopia/tratamento farmacológico , Soluções Oftálmicas , Refração Ocular , Austrália Ocidental/epidemiologia
5.
Exp Eye Res ; 179: 1-7, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30343040

RESUMO

Research with animal models of Pseudomonas aeruginosa keratitis has shown that use of a topical corticosteroid alone against an established infection can significantly increase the number of colonizing bacteria or worsen clinical disease. Moreover, retrospective analysis has suggested that corticosteroid use in humans is associated with an increased risk of keratitis in eyes with pre-existing disease. Thus, while corticosteroids are often used to reduce ocular inflammation in the absence of infection, the risk of opportunistic infection remains a concern. However, the effect of corticosteroids on the intrinsic barrier function of uninfected corneas is unknown. Here, we tested if short-term topical corticosteroid treatment of an uninfected murine cornea would increase susceptibility to P. aeruginosa colonization or infection after epithelial injury. Topical prednisolone acetate (1%) was administered to one eye of C57BL/6 mice three times a day for 3 days; control eyes were treated with sterile PBS. Prior to inoculation with a cytotoxic P. aeruginosa corneal isolate strain 6206, corneas were subject to superficial-injury by tissue paper blotting, or scratch-injured followed by 12 h of healing. Previously we have shown that blotting renders mouse corneas susceptible to P. aeruginosa adhesion, but not infection, while 12 h healing reduces susceptibility to infection after scratching. Corneas were evaluated at 48 h for bacterial colonization and microbial keratitis (MK). To monitor impact on wound healing, corneal integrity was examined by fluorescein staining immediately after scarification and after 12 h healing. For both the tissue paper blotting and scratch-injury models, there was no significant difference in P. aeruginosa colonization at 48 h between corticosteroid-pretreated eyes and controls. With the blotting model, one case of MK was observed in a control (PBS-pretreated) cornea; none in corticosteroid-pretreated corneas. With the 12 h healing model, MK occurred in 6 of 17 corticosteroid-pretreated eyes versus 2 of 17 controls, a difference not statistically significant. Corticosteroid-pretreated eyes showed greater fluorescein staining 12 h after scarification injury, but this did not coincide with increased colonization or MK. Together, these data show that short-term topical corticosteroid therapy on an uninfected murine cornea does not necessarily enhance its susceptibility to P. aeruginosa colonization or infection after injury, even when it induces fluorescein staining.


Assuntos
Lesões da Córnea/microbiologia , Infecções Oculares Bacterianas/microbiologia , Glucocorticoides/uso terapêutico , Prednisolona/análogos & derivados , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Administração Oftálmica , Animais , Córnea/efeitos dos fármacos , Lesões da Córnea/diagnóstico , Úlcera da Córnea/diagnóstico , Úlcera da Córnea/microbiologia , Modelos Animais de Doenças , Suscetibilidade a Doenças , Epitélio Corneano/lesões , Infecções Oculares Bacterianas/diagnóstico , Feminino , Fluoresceína/metabolismo , Corantes Fluorescentes/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Prednisolona/uso terapêutico , Pré-Medicação , Infecções por Pseudomonas/diagnóstico , Estudos Retrospectivos , Cicatrização
6.
Arterioscler Thromb Vasc Biol ; 37(9): 1727-1731, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28751573

RESUMO

OBJECTIVE: Previous genetic lineage tracing studies showed that Sox10+ cells differentiate into vascular mural cells, limited to neural crest-derived blood vessels in craniofacial tissues, aortic arch, pulmonary arch arteries, brachiocephalic, carotid arteries, and thymus. The purpose of this study was to investigate the contribution of Sox10+ cells to the vascular development in other tissues and organs and their relationship with neural crest. APPROACH AND RESULTS: Using genetic lineage tracing technique based on Cre/LoxP system, we examined blood vessels in the adult organs of the mice expressing Sox10-Cre/Rosa-LoxP-red fluorescent protein or Wnt1-Cre/Rosa-LoxP-red fluorescent protein by immunohistological analysis. In addition to previously reported tissues and organs derived from neural crest, we showed that Sox10+ cells also contributed to vascular mural cells in the lung, spleen, and kidney, which are derived from non-neural crest origin as evidenced by red fluorescent protein-negative blood vessels in these 3 organs of Wnt1-Cre/Rosa-LoxP-red fluorescent protein mice. CONCLUSIONS: This study demonstrates that Sox10+ cells contribute to pericytes and smooth muscle cells in most parts of the body, including those from neural crest and non-neural crest, which has significant implications in vascular remodeling under physiological and pathological conditions.


Assuntos
Linhagem da Célula , Rim/irrigação sanguínea , Pulmão/irrigação sanguínea , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Crista Neural/metabolismo , Pericitos/metabolismo , Fatores de Transcrição SOXE/metabolismo , Baço/irrigação sanguínea , Animais , Imunofluorescência , Genótipo , Integrases/genética , Proteínas Luminescentes/biossíntese , Proteínas Luminescentes/genética , Camundongos Transgênicos , Morfogênese , Músculo Liso Vascular/citologia , Neovascularização Fisiológica , Crista Neural/citologia , Fenótipo , Fatores de Transcrição SOXE/genética , Remodelação Vascular , Proteína Wnt1/genética , Proteína Vermelha Fluorescente
7.
Optom Vis Sci ; 91(2): 133-41, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24317134

RESUMO

PURPOSE: This study aimed to examine the effects of demographic, lens performance, and ocular surface response measures on contact lens-related discomfort and dryness, using a large contact lens study database. METHODS: A total of 4164 records were extracted from a database of 220 subjects participating in 46 silicone hydrogel contact lens studies. Subjects discontinued lens wear for 24 hours and were then fit with either comfilcon A or enfilcon A lenses. The fit and performance of the lenses, along with subjective comfort and dryness, were assessed on insertion and after 3 and 6 hours of wear. After 6 hours of wear, ocular surface health was also assessed by fluorescein slitlamp examination. RESULTS: Decreased comfort at 3 hours after insertion was associated with excessive lens movement (p < 0.001), front surface deposits (p = 0.004), poor wettability (p = 0.014), and Asian ethnicity (p < 0.001). After 6 hours of wear, decreased comfort remained associated with greater lens movement (p = 0.032) and Asian ethnicity (p < 0.001), along with inferior corneal staining (p < 0.001). Dryness after 3 hours of wear was associated with greater lens movement (p < 0.001), Asian ethnicity (p < 0.001), increased deposits (p < 0.001), and poor wettability (p < 0.001). Dryness after 6 hours of wear remained associated with greater lens movement (p < 0.001) and Asian ethnicity (p < 0.001), along with inferior corneal staining (p < 0.001) and inferior lens decentration (p = 0.001). CONCLUSIONS: Excessive lens movement, inferior lens decentration, poor surface wettability and deposits, inferior corneal staining, and Asian ethnicity are associated with discomfort and dryness. Clinicians should consider all these factors to achieve the most comfortable and successful contact lens fit.


Assuntos
Lentes de Contato Hidrofílicas/efeitos adversos , Síndromes do Olho Seco/etiologia , Transtornos da Visão/etiologia , Adolescente , Adulto , Bases de Dados Factuais , Síndromes do Olho Seco/fisiopatologia , Feminino , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato , Masculino , Satisfação do Paciente , Ajuste de Prótese , Silicones , Fatores de Tempo , Transtornos da Visão/fisiopatologia , Visão Ocular/fisiologia , Adulto Jovem
8.
J Biomol Struct Dyn ; : 1-10, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39258938

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has quickly become a global health pandemic. Among the viral proteins, RNA-dependent RNA polymerase (RdRp) is responsible for viral genome replication and has emerged as a promising target against SARS-CoV-2 infection. Dietary bioactive compounds represent an important source of evolutionarily optimized molecules with antiviral properties against SARS-CoV-2 RdRp. We investigated the inhibitory potential effects of different phytochemicals against SARS-CoV-2 RdRp, including andrographolide, kaempferol, resveratrol, and silibinin. Unlike the other investigated compounds, kaempferol exhibited a significant dose-dependent in vitro inhibition of SARS-CoV-2 RdRp activity. To assess the binding interactions and stability of the SARS-CoV-2 RdRp-kaempferol complex, we performed in silico techniques, including molecular docking, quantum chemical calculation, and molecular dynamics simulations. We found strong binding affinities and stability between kaempferol and SARS-CoV-2 RdRp variants (Wuhan and Omicron). These findings provide valuable insights into the antiviral properties of kaempferol as a stable inhibitor of SARS-CoV-2 RdRp.Communicated by Ramaswamy H. Sarma.

9.
Biomed Pharmacother ; 161: 114425, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36812712

RESUMO

Sirtuin 1 (SIRT1) belongs to the histone deacetylase enzyme family and its activity regulates various signaling networks associated with aging. SIRT1 is widely involved in a large number of biological processes, including senescence, autophagy, inflammation, and oxidative stress. In addition, SIRT1 activation may improve lifespan and health in numerous experimental models. Therefore, SIRT1 targeting is a potential strategy to delay or reverse aging and age-related diseases. Although SIRT1 is activated by a wide array of small molecules, only a limited number of phytochemicals that directly interact with SIRT1 have been identified. Using the Geroprotectors.org database and a literature search, the aim of this study was to identify geroprotective phytochemicals that might interact with SIRT1. We performed molecular docking, density functional theory studies, molecular dynamic simulations (MDS), and absorption, distribution, metabolism, excretion, and toxicity (ADMET) prediction to screen potential candidates against SIRT1. After the initial screening of 70 phytochemicals, crocin, celastrol, hesperidin, taxifolin, vitexin, and quercetin had significant binding affinity scores. These six compounds established multiple hydrogen-bonding and hydrophobic interactions with SIRT1 and showed good drug-likeness and ADMET properties. In particular, crocin was further analyzed using MDS to study its complex with SIRT1 during simulation. Crocin has a high reactivity to SIRT1 and can form a stable complex with it, showing a good ability to fit into the binding pocket. Although further investigations are required, our results suggest that these geroprotective phytochemicals, especially crocin, are novel interacting partners of SIRT1.


Assuntos
Simulação de Dinâmica Molecular , Sirtuína 1 , Simulação de Acoplamento Molecular , Sirtuína 1/metabolismo , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química
10.
RSC Adv ; 13(26): 17587-17594, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37312988

RESUMO

Two styryl-lactone derivatives (1 and 2) were isolated from the aerial parts of Goniothalamus elegans. Compound 1 is a newly discovered natural product, and compound 2 is reported in this plant for the first time. The absolute configuration of 1 was determined based on the ECD spectrum. The two styryl-lactone derivatives were tested for cytotoxicity activity against five cancer cell lines and human embryonic kidney cells. The newly discovered compound demonstrated potent cytotoxicity, with IC50 values ranging from 2.05 to 3.96 µM. Computational methods were also applied to investigate the mechanism of the cytotoxic activity of the two compounds. Density functional theory and molecular mechanisms were used to assess the interaction between protein targets to compound 1 and 2, respectively, through the EGF/EGFR signaling pathway. The results indicated that 1 showed a strong binding affinity for two proteins EGFR and HER-2. Finally, ADMET predictions were used to validate the pharmacokinetics and toxicity of these compounds. The results showed that both compounds are likely to be absorbed in the gastrointestinal tract and penetrate the blood-brain barrier. Based on our findings, these compounds may have potential for further studies to be developed into active ingredients for cancer treatment.

11.
J Behav Med ; 34(4): 254-67, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21127959

RESUMO

Worldwide, pneumonia causes 14% of deaths among children and infants (ages 4 weeks to 5 years). UNICEF and WHO have established treatment guidelines to reduce risk of death from pneumonia including caregiver symptom recognition, appropriate care, and use of antibiotics. In June 2008, cross-sectional survey data were collected in Khanh Hoa Province Viet Nam with 329 mothers of children under 6 years. In relation to pneumonia and associated symptoms (fever >38 °C, strong cough, "fast or difficult" breathing), data were collected on perceptions of symptom severity and child vulnerability, reported healthcare utilization including use of antibiotics, sources of health information, and barriers to care. Pearson's chi square, independent t tests, and multinomial analysis were conducted to assess different patterns of reported healthcare utilization in relation to residency (rural/urban), mother's education, and household income. Outcomes include rural and urban residency-based patterns related to perceptions of child's vulnerability and symptom severity, health facility utilization and barriers to care, and reported use of antibiotics during previous episodes of pneumonia. Implications include the need to target different healthcare facilities in urban and rural Viet Nam in relation to education about symptoms of childhood pneumonia and associated treatments.


Assuntos
Serviços de Saúde Comunitária/estatística & dados numéricos , Mães/psicologia , Pneumonia/psicologia , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adulto , Antibacterianos/uso terapêutico , Atitude Frente a Saúde , Pré-Escolar , Informação de Saúde ao Consumidor/estatística & dados numéricos , Tosse/complicações , Tosse/diagnóstico , Tosse/tratamento farmacológico , Tosse/psicologia , Dispneia/complicações , Dispneia/diagnóstico , Dispneia/tratamento farmacológico , Dispneia/psicologia , Feminino , Febre/complicações , Febre/diagnóstico , Febre/tratamento farmacológico , Febre/psicologia , Inquéritos Epidemiológicos , Humanos , Lactente , Masculino , Medicina Tradicional/estatística & dados numéricos , Pneumonia/complicações , Pneumonia/tratamento farmacológico , Vietnã
12.
Youth Soc ; 43(1): 118-141, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21373363

RESUMO

A randomly selected cross-sectional survey was conducted with 880 youth (16 to 24 years) in Nha Trang City to assess relationships between alcohol consumption and sexual behaviors. A timeline followback method was employed. Chi-square, generalized logit modeling and logistic regression analyses were performed. Of the sample, 78.2% male and 56.1% female respondents ever consumed alcohol. Males reporting sexual behaviors (vaginal, anal, oral sex) had a significantly higher calculated peak BAC of 0.151 compared to 0.082 for males reporting no sexual intimacy (p < .0001). Females reporting sexual behaviors had a peak BAC of 0.072 compared to 0.027 for those reporting no sexual intimacy (p = .016). Fifty percent of (33/66) males and 30.4% (7/23) females report event specific drinking and engagement in sexual behaviors. Males reporting 11+ drinks in 30 days had more sexual partners than those reporting 1 to 10 drinks (p = .037). Data suggest different physical and psychosocial mediators between alcohol consumption and sexual behaviors by gender.

13.
Rev Laryngol Otol Rhinol (Bord) ; 131(2): 97-102, 2010.
Artigo em Francês | MEDLINE | ID: mdl-21284224

RESUMO

OBJECTIVES: Retrospective study about the indications and the results of the end to-end hypoglossofacial anastomosis (AHF tt). MATERIALS AND METHODS: Between 2004 and 2010, 38 patients were able to benefit from an AHF tt. It was about 13 men and 25 women. The mean age was of 40 years and the average deadline of coverage after facial paralysis was of 21.3 months. The etiology of the paralysis was in 47.7% of the cases a surgery for vestibular schwannoma and in 18% of the cases, of the facial nerve schwannoma. Besides the AHF tt, a golden weight was put to 6 of our patients. A specific and premature speech therapy remediation was realized at our all patient's. RESULTS: The beginning of recovery was spread out between 3 and 9 months. The final result was a grade III HB (37%) and IV HB (60%). Only a case of grade VHB was observed. The complications often reported by the AHF tt were very widely decreased by the specific reeducation. CONCLUSION: AHF tt is a particularly reliable technique, for rehabilitation of facial palsy, when the peripheral branches are intact and it, for the deadline 4-years-old subordinate except particular cases.


Assuntos
Anastomose Cirúrgica/métodos , Nervo Facial/cirurgia , Nervo Hipoglosso/cirurgia , Adulto , Idoso , Paralisia Facial/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
14.
Optom Vis Sci ; 86(4): e324-31, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19225431

RESUMO

PURPOSE: Composed of sheets of cells detached from the underlying conjunctiva, conjunctival epithelial flap (CEF) is a recently reported phenomenon associated with contact lens wear with potential consequences for ocular health. Although CEF is generally asymptomatic, it is not known to what extent it might increase the longer-term risk of discomfort, inflammatory response, or infection. In this study, we use survival analysis methods to obtain unbiased estimates of the probability of developing CEF, the mean survival time free of CEF, and the effects of age, gender, ethnicity, and contact lens type. METHODS: Two hundred four subjects were recruited for a continuous wear (CW) study of silicone hydrogel (SiH) and gas permeable (GP) contact lenses. Subjects were examined by optometrists throughout contact lens adaptation and CW periods. Statistical methods included the Kaplan-Meier nonparametric estimator of the survival function and the Cox proportional hazards model for estimating the relative effects of covariates. RESULTS: Of the 204 subjects, 72 (35%) developed CEF. In 64% of cases, CEFs were observed bilaterally. The majority of cases (90.3%) presented with CEF in the superior conjunctiva. Mean survival time free of CEF was longer for GP lenses (94.3 days) than for SiH lenses (76.5 days), and the probability of developing CEF was significantly greater for SiH lenses (p = 0.002). Although there was some evidence that women and non-Asians remain free of CEF longer, the effects of age, gender, and ethnicity were not statistically significant. CONCLUSIONS: There was a significantly increased risk of CEF in subjects wearing SiH lenses, compared with GP lenses. Subjects wearing SiH lenses remained free of CEF for a shorter time on average. Further study is needed to determine whether the increased incidence of CEF in CW with SiH lenses poses an increased risk of adverse ocular response or infection.


Assuntos
Doenças da Túnica Conjuntiva/etiologia , Lentes de Contato/efeitos adversos , Doenças da Túnica Conjuntiva/epidemiologia , Doenças da Túnica Conjuntiva/patologia , Epitélio/patologia , Desenho de Equipamento , Feminino , Gases , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato , Incidência , Estimativa de Kaplan-Meier , Masculino , Permeabilidade , Modelos de Riscos Proporcionais , Medição de Risco , Silicones , Fatores de Tempo , Adulto Jovem
15.
Ocul Surf ; 17(1): 119-133, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30439473

RESUMO

PURPOSE: Contact lens wear carries a risk of complications, including corneal infection. Solving these complications has been hindered by limitations of existing animal models. Here, we report development of a new murine model of contact lens wear. METHODS: C57BL/6 mice were fitted with custom-made silicone-hydrogel contact lenses with or without prior inoculation with Pseudomonas aeruginosa (PAO1-GFP). Contralateral eyes served as controls. Corneas were monitored for pathology, and examined ex vivo using high-magnification, time-lapse imaging. Fluorescent reporter mice allowed visualization of host cell membranes and immune cells. Lens-colonizing bacteria were detected by viable counts and FISH. Direct-colony PCR was used for bacterial identification. RESULTS: Without deliberate inoculation, lens-wearing corneas remained free of visible pathology, and retained a clarity similar to non-lens wearing controls. CD11c-YFP reporter mice revealed altered numbers, and distribution, of CD11c-positive cells in lens-wearing corneas after 24 h. Worn lenses showed bacterial colonization, primarily by known conjunctival or skin commensals. Corneal epithelial cells showed vacuolization during lens wear, and after 5 days, cells with phagocyte morphology appeared in the stroma that actively migrated over resident keratocytes that showed altered morphology. Immunofluorescence confirmed stromal Ly6G-positive cells after 5 days of lens wear, but not in MyD88 or IL-1R gene-knockout mice. P. aeruginosa-contaminated lenses caused infectious pathology in most mice from 1 to 13 days. CONCLUSIONS: This murine model of contact lens wear appears to faithfully mimic events occurring during human lens wear, and could be valuable for experiments, not possible in humans, that help solve the pathogenesis of lens-related complications.


Assuntos
Lentes de Contato , Córnea/microbiologia , Infecções Oculares Bacterianas/microbiologia , Ceratite/microbiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Receptores Tipo I de Interleucina-1/genética , Animais , Contagem de Colônia Microbiana , Lentes de Contato/efeitos adversos , Córnea/patologia , Modelos Animais de Doenças , Infecções Oculares Bacterianas/metabolismo , Infecções Oculares Bacterianas/patologia , Ceratite/metabolismo , Ceratite/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Confocal , Infecções por Pseudomonas/metabolismo , Infecções por Pseudomonas/patologia , Receptores Tipo I de Interleucina-1/metabolismo , Tomografia de Coerência Óptica
16.
J Photochem Photobiol B ; 182: 108-114, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29656219

RESUMO

Silver nanoparticles (Ag NPs) were synthesized by an improved green synthesis method via a photo-reduction process using low-power UV light in the presence of poly (vinyl pyrrolidone) (PVP) as the surface stabilizer. The effective synthesis process was achieved by optimized synthesis parameters such as C2H5OH: H2O ratio, AgNO3: PVP ratio, pH value, and reducing time. The formation of Ag NPs was identified by Ultraviolet-visible (UV-vis) absorption spectra, X-ray diffraction pattern (XRD) and Fourier transform infrared spectroscopy (FTIR) spectra. Ag NPs were crystallized according to (111), (200), and (220) planes of the face-centered cubic. The transmission electron microscopy (TEM) image showed that the morphology of Ag NPs was uniform spherical with the average particle size of 16 ±â€¯2 nm. The results of XRD pattern, TEM image, and dynamic light scattering (DLS) analysis proved that Ag crystals with uniform size were formed after the reduction process. The mechanism of the formation of Ag NPs was proposed and confirmed by FTIR spectra. The antibacterial activity of Ag NPs against Escherichia coli (E. coli) was tested and approximately 100% of E. coli was eliminated by Ag NPs 35 ppm. In the future, this study can become a new process for the application of Ag NPs as an antibiotic in the industrial scale.


Assuntos
Antibacterianos , Escherichia coli/efeitos dos fármacos , Química Verde , Microbiologia Industrial/métodos , Nanopartículas Metálicas/química , Prata , Antibacterianos/síntese química , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Tamanho da Partícula , Prata/química , Prata/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Am J Trop Med Hyg ; 76(4): 732-6, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17426180

RESUMO

Vietnam is participating in a global de-worming effort that aims to treat 650 million school children regularly by 2010. The treatment used in Vietnam is single dose oral mebendazole (Phardazone) 500 mg. We tested the efficacy of single dose mebendazole 500 mg in the therapy of hookworm infection in a randomized double-blind placebo-controlled trial among 271 Vietnamese schoolchildren. The treatment efficacy of single dose mebendazole in children did not differ significantly from placebo, with a reduction in mean eggs per gram of feces relative to placebo of 31% (95% CI -9 to 56%, P = 0.1). In light of these findings we then carried out a similar randomized trial comparing triple dose mebendazole, single dose albendazole, and triple dose albendazole against placebo in 209 adults in the same area. The estimated reduction in mean post-treatment eggs per gram of feces relative to placebo was 63% (95% CI 30-81%) for triple mebendazole, 75% (47-88%) for single albendazole, and 88% (58-97%) for triple albendazole. Our results suggest that single dose oral mebendazole has low efficacy against hookworm infection in Vietnam, and that it should be replaced by albendazole. These findings are of major public health relevance given the opportunity costs of treating entire populations with ineffective therapies. We recommend that efficacy of anti-helminth therapies is pilot tested before implementation of national gut worm control programs.


Assuntos
Infecções por Uncinaria/tratamento farmacológico , Infecções por Uncinaria/parasitologia , Mebendazol/farmacologia , Mebendazol/uso terapêutico , Adolescente , Adulto , Idoso , Albendazol/administração & dosagem , Albendazol/farmacologia , Albendazol/uso terapêutico , Animais , Anti-Helmínticos/administração & dosagem , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Criança , Método Duplo-Cego , Feminino , Humanos , Masculino , Mebendazol/administração & dosagem , Pessoa de Meia-Idade , Vietnã/epidemiologia
18.
J Assoc Nurses AIDS Care ; 18(2): 48-59, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17403496

RESUMO

As rates of HIV increase in Vietnam, there is a need for data on social relations and sexual risk and protective behaviors among Vietnamese adolescents in a context of rapid social and economic changes. The authors report results from qualitative interviews with 159 Vietnamese adolescents living in Hanoi, Nha Trang City, and Ninh Hoa District and a survey of 886 adolescents in these same three sites. In the qualitative interviews, youths report a strong adherence to ideals and values regarding abstinence outside of marriage. Youths reported low rates of engagement in vaginal, anal, and/or oral sex with a significant difference in reported behaviors between males (29/469, 6.2%) and females (7/416, 1.7%; p = .000). A total of 15 of 32 (46.9%) sexually active youths reported rarely or never using condoms. Females had significantly higher scores for perceived sexual stigma than males (t = -10.22 [95% confidence interval (CI); -3.72 to -2.52; p = .000) whereas males scored significantly lower than females on a scale of perceived self-efficacy for abstinence (t = 5.31 [95% CI; .27 to .59]; p = .000). The stigmatization of sexual relations outside of marriage particularly for young women reinforces abstinence; however, these same values decrease adolescents' ability to obtain accurate information about sexuality and HIV and sexually transmitted infections and engage in safer sex.


Assuntos
Comportamento do Adolescente/etnologia , Infecções por HIV , Gravidez na Adolescência , Comportamento Sexual/etnologia , Infecções Sexualmente Transmissíveis , Estereotipagem , Adolescente , Atitude Frente a Saúde/etnologia , Feminino , Infecções por HIV/etnologia , Infecções por HIV/prevenção & controle , Comportamentos Relacionados com a Saúde/etnologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Motivação , Pesquisa Metodológica em Enfermagem , Gravidez , Gravidez na Adolescência/etnologia , Gravidez na Adolescência/prevenção & controle , Gravidez não Desejada/etnologia , Teoria Psicológica , Psicologia do Adolescente , Pesquisa Qualitativa , Assunção de Riscos , Abstinência Sexual/etnologia , Infecções Sexualmente Transmissíveis/etnologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Mudança Social , Inquéritos e Questionários , Vietnã/epidemiologia
19.
Gastroenterol Clin Biol ; 31(5): 493-7, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17541339

RESUMO

OBJECTIVES: The strongest environmental factors identified for ulcerative colitis (UC) are cigarette smoking and appendectomy. However, most studies have been performed using case-controls from hospital-based populations. The purpose of this study was to compare the history of previous appendectomy and smoking habits in a group of patients with UC and a control group, followed by gastroenterologists in private practice. METHODS: We performed a case control study in which 100 physicians recruited UC-patients and age and sex matched controls. Data were collected during a single visit. Based on a standardized questionnaire, UC patients and controls were divided into never, former or current smokers, and into subjects with or without a previous history of appendectomy. RESULTS: One hundred and ninety eight age- and sex-matched pairs of UC patients and controls were included. The prevalence of appendectomy in the UC-patients and control group was 12% and 46%, respectively. The pairwise-matched OR of ulcerative colitis for previous appendectomy was 0.10 (95% CI, 0.05-0.21) (P<0.0001). The OR for former and never smokers versus current smokers was 2.40 (95% CI 1.31-4.38) (P=0.004). In UC-patients, the OR of family history of UC compared with controls was 2.80 (95% CI, 1.01-7.77) (P=0.048). CONCLUSIONS: This case-control study confirmed a strong negative correlation between both appendectomy and tobacco smoking, and ulcerative colitis in patients followed-up by gastroenterological practitioners.


Assuntos
Apendicectomia , Colite Ulcerativa/etiologia , Fumar/efeitos adversos , Adulto , Estudos de Casos e Controles , Colite Ulcerativa/genética , Colonoscopia , Doença de Crohn/genética , Feminino , Seguimentos , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Masculino , Recidiva , Fatores de Risco
20.
Artigo em Inglês | MEDLINE | ID: mdl-29250483

RESUMO

Fluorescent protein-based biosensors are indispensable molecular tools for life science research. The invention and development of high-fidelity biosensors for a particular molecule or molecular event often catalyze important scientific breakthroughs. Understanding the structural and functional organization of brain activities remain a subject for which optical sensors are in desperate need and of growing interest. Here, we review genetically encoded fluorescent sensors for imaging neuronal activities with a focus on the design principles and optimizations of various sensors. New bioluminescent sensors useful for deep-tissue imaging are also discussed. By highlighting the protein engineering efforts and experimental applications of these sensors, we can consequently analyze factors influencing their performance. Finally, we remark on how future developments can fill technological gaps and lead to new discoveries.

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