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1.
Rev Endocr Metab Disord ; 21(1): 37-44, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31965434

RESUMO

Brown adipose tissue (BAT) is an endocrine adipose tissue with attributes to dissipate energy as heat in response to changes in temperature and diet. Infrared thermography (IRT) has been studied in recent years in the assessment of BAT thermogenesis, as an option to positron emission tomography - computed tomography (PET-CT), because of several advantages. We performed a systematic review on the use of IRT in BAT assessment. Comprehensive online search was performed in different databases. The QUADAS 2 tool was used to evaluate studies' quality. 12 studies fit the inclusion criteria, whereas only one of these was considered of low risk of bias. 10 studies were favorable to IRT appliance in BAT evaluation, observing elevation of supraclavicular skin temperature correlated with BAT activity. Studies were heterogeneous in design, and a meta-analysis was precluded. Further studies with similar methodologies are needed. Conclusion: Despite the large number of published methodologies, IRT is a promising method for detecting BAT activation. Current knowledge already allows a better understanding of thermography to improve and standardize the technique.


Assuntos
Tecido Adiposo Marrom/metabolismo , Termografia , Metabolismo Energético , Feminino , Humanos , Raios Infravermelhos , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Temperatura Cutânea
2.
Clin Endocrinol (Oxf) ; 89(2): 164-177, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29668062

RESUMO

BACKGROUND: Follow-up data on patients with 46,XY partial gonadal dysgenesis (PGD) until adulthood are scarce, making information on prognosis difficult. OBJECTIVE: To analyse the long-term outcomes of patients with 46,XY PGD regarding testosterone production, germ cell tumour risk, genotype and psychosexual adaptation. METHODS: A retrospective longitudinal study of 33 patients (20 assigned male and 13 patients assigned female at birth). Molecular diagnosis was performed by Sanger sequencing or by targeted massively parallel sequencing of 63 genes related to disorders of sex development (DSDs). RESULTS: Age at first and last visit ranged from 0.1 to 43 and from 17 to 53 years, respectively. Spontaneous puberty was observed in 57% of the patients. During follow-up, six of them had a gonadectomy (four due to female gender, and two because of a gonadal tumour). At last evaluation, five of six patients had adult male testosterone levels (median 16.7 nmol/L, range 15.3-21.7 nmol/L) and elevated LH and FSH levels. Germ cell tumours were found in two postpubertal patients (one with an abdominal gonad and one patient with Frasier syndrome). Molecular diagnosis was possible in 11 patients (33%). NR5A1 variants were the most prevalent molecular defects (n = 6), and four of five patients harbouring them developed spontaneous puberty. Gender change was observed in four patients, two from each sex assignment group; all patients reported satisfaction with their gender at final evaluation. Sexual intercourse was reported by 81% of both gender and 82% of them reported satisfaction with their sexual lives. CONCLUSION: Spontaneous puberty was observed in 57% of the patients with 46,XY PGD, being NR5A1 defects the most prevalent ones among all the patients and in those with spontaneous puberty. Gender change due to gender dysphoria was reported by 12% of the patients. All the patients reported satisfaction with their final gender, and most of them with their sexual life.

3.
Exp Eye Res ; 134: 39-46, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25795052

RESUMO

Corneal avascularization is essential for normal vision. Several antiangiogenic factors were identified in cornea such as endostatin and angiostatin. Cathepsin V, which is highly expressed in the cornea, can hydrolyze human plasminogen to release angiostatin fragments. Herein, we describe a detailed investigation of the expression profile of cathepsins B, L, S and V in the human cornea and the role of cysteine peptidases in modulating angiogenesis both in vitro and in vivo. We used various methodological tools for this purpose, including real-time PCR, SDS-PAGE, western blotting, catalytic activity assays, cellular assays and induction of corneal neovascularity in rabbit eyes. Human corneal enzymatic activity assays revealed the presence of cysteine proteases that were capable of processing endogenous corneal plasminogen to produce angiostatin-like fragments. Comparative real-time analysis of cathepsin B, L, S and V expression revealed that cathepsin V was the most highly expressed, followed by cathepsins L, B and S. However, cathepsin V depletion revealed that this enzyme is not the major cysteine protease responsible for plasminogen degradation under non-pathological conditions. Furthermore, western blotting analysis indicated that only cathepsins B and S were present in their enzymatically active forms. In vivo analysis of angiogenesis demonstrated that treatment with the cysteine peptidase inhibitor E64 caused a reduction in neovascularization. Taken together, our results show that human corneal cysteine proteases are critically involved in angiogenesis.


Assuntos
Catepsinas/metabolismo , Neovascularização da Córnea/enzimologia , Modelos Animais de Doenças , Animais , Western Blotting , Catepsinas/genética , Neovascularização da Córnea/patologia , Eletroforese em Gel de Poliacrilamida , Regulação da Expressão Gênica/fisiologia , Humanos , Plasminogênio/metabolismo , RNA Mensageiro/genética , Coelhos , Reação em Cadeia da Polimerase em Tempo Real , Doadores de Tecidos
4.
Am J Ophthalmol ; 155(4): 705-12, 712.e1, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23253911

RESUMO

PURPOSE: To investigate the in vitro effect of pH, osmolarity, solvent, and light interaction on currently used and novel dyes to minimize dye-related retinal toxicity. DESIGN: Laboratory investigation. METHODS: Retinal pigment epithelium (RPE) human cells (ARPE-19) were exposed for 10 minutes to different pH solutions (4, 5, 6, 7, 7.5, 8, and 9) and glucose solutions (2.5%, 5.0%, 10%, 20%, 40%, and 50%) with osmolarity from 142 to 2530 mOsm, with and without 0.5 mg/mL trypan blue. R28 cells were also incubated with glucose (150, 310, and 1000 mOsm) and mannitol used as an osmotic control agent in both experiments. Dye-light interaction was assessed by incubating ARPE-19 for 10 minutes with trypan blue, brilliant blue, bromophenol blue, fast green, light green, or indigo carmine (0.05 mg/mL diluted in balanced saline solution) in the presence of high-brightness xenon and mercury vapor light sources. RESULTS: Solutions with nonphysiologic pH, below 7 and above 7.5, proved to be remarkably toxic to RPE cells with or without trypan blue. Also, all glucose solutions were deleterious to RPE (P < .001) even in iso-osmolar range. No harmful effect was found with mannitol solutions. Among the dyes tested, only light green and fast green were toxic to ARPE-19 (P < .001). Light exposure did not increase RPE toxicity either with xenon light or mercury vapor lamp. CONCLUSIONS: Solutions containing glucose as a dye solvent or nonphysiologic pH should be used with care in surgical situations where the RPE is exposed. Light exposure under present assay conditions did not increase the RPE toxicity.


Assuntos
Corantes/toxicidade , Epitélio Pigmentado da Retina/efeitos dos fármacos , Acetatos/farmacologia , Sobrevivência Celular , Células Cultivadas , Combinação de Medicamentos , Solução Hipertônica de Glucose , Humanos , Concentração de Íons de Hidrogênio , Luz/efeitos adversos , Minerais/farmacologia , Concentração Osmolar , Estudos Prospectivos , Neurônios Retinianos/efeitos dos fármacos , Neurônios Retinianos/patologia , Neurônios Retinianos/efeitos da radiação , Epitélio Pigmentado da Retina/patologia , Epitélio Pigmentado da Retina/efeitos da radiação , Cloreto de Sódio/farmacologia , Azul Tripano
5.
Am J Ophthalmol ; 151(3): 401-5.e1, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21251644

RESUMO

PURPOSE: To summarize current concepts and recent data from the literature about different vitrectomy machines and small-gauge systems based on physical laws. DESIGN: Interpretive essay. METHODS: Review and synthesis of selected recent literature with interpretation and perspective. RESULTS: Pars plana vitrectomy can be performed with a wide variety of treatment strategies, for multiple diseases, and with different materials (solids and fluids). We discuss a variety of machines and system settings (peristaltic pump, duty cycle, aspiration, and infusion controls) targeting safer and the most effective surgery with detailed explanations of the physical properties. CONCLUSIONS: Effective management of new surgical strategies is based on recognizing and addressing various physical characteristics in disease and ocular settings. Although the properties of machine are expanding, the long-term efficacy and safety of most new approaches have yet to be established in controlled clinical trials.


Assuntos
Hidrodinâmica , Microcirurgia/instrumentação , Vitrectomia/instrumentação , Cirurgia Vitreorretiniana , Fenômenos Biomecânicos , Humanos , Microcirurgia/métodos , Sucção , Vitrectomia/métodos
6.
Surv Ophthalmol ; 54(5): 576-617, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19682624

RESUMO

Vital dyes have advanced diagnosis and surgical technique in various specialties, including oncology, gastroenterology, and ophthalmology. In ocular surgery vital dyes are widely used in cataract and vitreoretinal surgery. Worldwide, intra-operative use of trypan blue during cataract surgery has enhanced visualization of the anterior capsule during capsulorrhexis, and patent blue has been recently licensed in Europe for cataract surgery. For chromovitrectomy, the vital dyes indocyanine green, infracyanine green, and brilliant blue stain the internal limiting membrane, and trypan blue and triamcinolone acetonide help visualize epiretinal membranes and vitreous, respectively. Intra-operative vital dyes are finding uses in corneal, glaucoma, orbit, strabismus, and conjunctival surgery. We provide a summary of current knowledge of the use of vital dyes in ocular surgery. We review the properties of dyes, techniques of application, indications, and complications in ocular surgery. Vital dyes represent an expanding area of research, and novel dyes deserve further investigation.


Assuntos
Corantes , Oftalmopatias/cirurgia , Procedimentos Cirúrgicos Oftalmológicos , Coloração e Rotulagem/métodos , Corantes/efeitos adversos , Corantes/farmacologia , Humanos , Cuidados Intraoperatórios/métodos
7.
Ophthalmic Surg Lasers Imaging ; 39(4): 343-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18717446

RESUMO

A 42-year-old man developed progressive scleral iatrogenic staphyloma in the region of a previous trabeculectomy with mitomycin C after three sessions of diode laser transscleral cyclophotocoagulation for a refractory glaucoma secondary to trauma. After clinical and laboratory evaluations, no signs of systemic or autoimmune disorders were found. The patient underwent a reinforcement of the eye wall with a scleral patch over the staphyloma area and a glaucoma drainage device was implanted. Repeated transscleral cyclophotocoagulation procedures should be performed cautiously in patients who have had previous trabeculectomy.


Assuntos
Corpo Ciliar/cirurgia , Doença Iatrogênica , Fotocoagulação a Laser/efeitos adversos , Mitomicina , Esclera/patologia , Doenças da Esclera/etiologia , Trabeculectomia , Adulto , Terapia Combinada , Dilatação Patológica , Glaucoma/cirurgia , Humanos , Pressão Intraocular , Lasers Semicondutores , Masculino
8.
Dev Ophthalmol ; 42: 91-100, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18535383

RESUMO

Trypan blue (TB) is a blue vital dye with fine color properties to stain the anterior lens capsule and thereby may facilitate capsulorrhexis during cataract surgery. In addition, the blue stain may assist in the visualization of various preretinal membranes and tissues during vitreoretinal surgery in a procedure also called chromovitrectomy. TB has demonstrated great binding affinity for the glial epiretinal membranes, although it remains yet to be determined in which circumstances the dye may color the vitreous and internal limiting membrane. Most studies suggest that 0.06% TB does not pose harm to the retina, but at higher concentrations further investigation is necessary. In this paper, various aspects of the application of TB for chromovitrectomy are discussed including laboratory investigations, surgical technique and clinical outcomes.


Assuntos
Membrana Basal/patologia , Corantes , Membrana Epirretiniana/diagnóstico , Azul Tripano , Vitrectomia , Membrana Basal/cirurgia , Corantes/efeitos adversos , Membrana Epirretiniana/cirurgia , Humanos , Cápsula do Cristalino/patologia , Coloração e Rotulagem/métodos , Azul Tripano/efeitos adversos
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