Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
1.
Ophthalmol Retina ; 6(8): 693-701, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35314387

RESUMO

OBJECTIVE: To investigate visual acuity (VA) outcomes and OCT-based biomarkers of vision outcomes in eyes with glaucoma undergoing pars plana vitrectomy (PPV) for idiopathic epiretinal membrane (ERM). DESIGN: Retrospective, consecutive case-control series. A previously described ERM grading scale was utilized for OCT analysis. SUBJECTS: Eyes with glaucoma undergoing PPV for idiopathic ERM. INTERVENTION: PPV with membrane peel (MP) surgery. MAIN OUTCOME MEASURES: The primary outcome was VA at postoperative month 6. Outcomes were compared to a contemporary, matched control group of eyes without concurrent glaucoma undergoing PPV for idiopathic ERM. RESULTS: A total of 103 eyes from 103 patients with ERM and glaucoma were followed for a mean (± standard deviation) of 656 (± 421) days after PPV with MP surgery. Glaucoma was classified as open angle in 98 (95.1%) eyes and closed angle in 5 (4.9%) eyes. Visual acuity improved from 0.72 ± 0.48 (20/105) to 0.55 ± 0.51 (20/71) at 6 months and to 0.50 ± 0.56 (20/63) at final follow-up (P < 0.001 for both the time points). Eyes with preoperative inner microcystoid changes (n = 59; 57.3%) had significantly worse preoperative VA, postoperative VA at month 6, and final VA compared to eyes without inner microcystoid changes (P = 0.028, 0.004, and 0.007, respectively). Eyes were then compared to a matched control group of 139 eyes without glaucoma. Eyes with ERM and glaucoma had a higher rate of microcystic changes both before surgery (P < 0.001) and at postoperative month 6 (P < 0.001), and had a worse VA at 6 months (P = 0.03) and final follow-up (P = 0.04) compared to control eyes without glaucoma. Advanced disc cupping was the only factor independently correlated with worse 6-month (P = 0.01) and final (P = 0.007) VA in multivariate analysis. CONCLUSIONS: Preoperative inner microcystoid changes on OCT were present in over half of eyes with ERM and concurrent glaucoma, and may be a poor prognostic OCT biomarker. Eyes with ERM and concurrent glaucoma experienced worse vision outcomes compared to eyes with ERM alone, particularly those with advanced disc cupping.


Assuntos
Membrana Epirretiniana , Glaucoma , Vitrectomia , Estudos de Casos e Controles , Membrana Epirretiniana/patologia , Membrana Epirretiniana/cirurgia , Glaucoma/complicações , Glaucoma/patologia , Glaucoma/cirurgia , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Acuidade Visual
2.
J AOAC Int ; 102(6): 1651-1656, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30305203

RESUMO

Background: Mycotoxin contamination in oils remains an important food safety issue. To monitor the occurrence of mycotoxins in edible oils, it is important to develop analytical methods that can determine multiple mycotoxins in oil products. A stable isotope dilution LC-tandem MS (LC-MS/MS) method for the simultaneous determination of 12 mycotoxins in five edible oil matrixes (canola, corn, olive, peanut, and soybean oil) was developed and validated. Methods: Prior to extraction, the oil samples were fortified with ¹³C uniformly labeled internal standards (¹³C-IS) for 12 target mycotoxins, followed by extraction and LC-MS/MS analysis. Quantitation was achieved using solvent-only calibration standards, relative response factors of ¹³C-IS, and target mycotoxins. Results: The majority of recoveries in oil for ochratoxin A and aflatoxins B1, B2, G1, and G2 fortified at 1, 10, and 100 ng/g as well as deoxynivalenol; fumonisins B1, B2, and B3; T-2 toxin; HT-2 toxin; and zearalenone fortified at 10, 100, and 1000 ng/g ranged from 80 to 120% with RSDs of <20%. The method LOQs ranged from 0.1 ng/g (aflatoxin B1) to 6.4 ng/g (zearalenone). Among 16 U.S. market samples, zearalenone was detected in three corn oil samples at 37, 185, and 317 ng/g, respectively. T-2 toxin was found in two corn oil samples at 7 and 10 ng/g, respectively. Conclusions: The method provides sufficient selectivity, sensitivity, accuracy, and repeatability to screen edible oils for regulated mycotoxins such as aflatoxins at low nanogram per gram concentrations without using conventional standard addition or matrix-matched calibration standards to correct for matrix effects.


Assuntos
Cromatografia Líquida/métodos , Contaminação de Alimentos/análise , Micotoxinas/análise , Óleos de Plantas/análise , Espectrometria de Massas em Tandem/métodos , Isótopos de Carbono/química , Técnicas de Diluição do Indicador , Limite de Detecção
3.
Brain ; 141(12): 3405-3414, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30452554

RESUMO

Magnetic resonance guided focused ultrasound (MRgFUS) thalamotomy is a novel and minimally invasive ablative treatment for essential tremor. The size and location of therapeutic lesions producing the optimal clinical benefits while minimizing adverse effects are not known. We examined these relationships in patients with essential tremor undergoing MRgFUS. We studied 66 patients with essential tremor who underwent MRgFUS between 2012 and 2017. We assessed the Clinical Rating Scale for Tremor (CRST) scores at 3 months after the procedure and tracked the adverse effects (sensory, motor, speech, gait, and dysmetria) 1 day (acute) and 3 months after the procedure. Clinical data associated with the postoperative Day 1 lesions were used to correlate the size and location of lesions with tremor benefit and acute adverse effects. Diffusion-weighted imaging was used to assess whether acute adverse effects were related to lesions encroaching on nearby major white matter tracts (medial lemniscus, pyramidal, and dentato-rubro-thalamic). The area of optimal tremor response at 3 months after the procedure was identified at the posterior portion of the ventral intermediate nucleus. Lesions extending beyond the posterior region of the ventral intermediate nucleus and lateral to the lateral thalamic border were associated with increased risk of acute adverse sensory and motor effects, respectively. Acute adverse effects on gait and dysmetria occurred with lesions inferolateral to the thalamus. Lesions inferolateral to the thalamus or medial to the ventral intermediate nucleus were also associated with acute adverse speech effects. Diffusion-weighted imaging revealed that lesions associated with adverse sensory and gait/dysmetria effects compromised the medial lemniscus and dentato-rubro-thalamic tracts, respectively. Lesions associated with adverse motor and speech effects encroached on the pyramidal tract. Lesions larger than 170 mm3 were associated with an increased risk of acute adverse effects. Tremor improvement and acute adverse effects of MRgFUS for essential tremor are highly dependent on the location and size of lesions. These novel findings could refine current MRgFUS treatment planning and targeting, thereby improving clinical outcomes in patients.


Assuntos
Tremor Essencial/terapia , Tálamo/patologia , Terapia por Ultrassom , Idoso , Imagem de Tensor de Difusão , Tremor Essencial/diagnóstico , Tremor Essencial/patologia , Feminino , Humanos , Imagem por Ressonância Magnética Intervencionista , Masculino , Sensibilidade e Especificidade , Resultado do Tratamento , Substância Branca/patologia
4.
J Chem Inf Model ; 56(6): 1139-51, 2016 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-27154487

RESUMO

Virtual screening consists of docking libraries of small molecules to a target protein followed by rank-ordering of the resulting structures using scoring functions. The ability of scoring methods to distinguish between actives and inactives depends on several factors that include the accuracy of the binding pose during the docking step and the quality of the three-dimensional structure of the target. Here, we build on our previous work to introduce a new scoring approach (SVMGen) that uses machine learning trained with features from statistical pair potentials obtained from three-dimensional crystal structures. We use SVMGen and GlideScore to explore how enrichment or rank-ordering is affected by binding pose accuracy. To that end, we create a validation set that consists strictly of proteins whose crystal structure was solved in complex with their inhibitors. For the rank-ordering studies, we use crystal structures from PDBbind along with corresponding binding affinity data provided in the database. In addition to binding pose, we investigate the effect of using modeled structures for the target on the enrichment performance of SVMGen and GlideScore. To accomplish this, we generated homology models for protein kinases in DUD-E for which crystal structures are available to enable comparison of enrichment between modeled and crystal structure. We also generate homology models for kinases in SARfari for which there are many known small-molecule inhibitors but no known crystal structure. These models are used to assess the ability of SVMGen and GlideScore to distinguish between actives and decoys. We focus our work on protein kinases considering the wealth of structural and binding affinity data that exists for this family of proteins.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Simulação de Acoplamento Molecular , Bibliotecas de Moléculas Pequenas/química , Máquina de Vetores de Suporte , Cristalografia por Raios X , Ligantes , Ligação Proteica , Proteínas Quinases/química , Proteínas Quinases/metabolismo , Interface Usuário-Computador
5.
Methods Mol Biol ; 1278: 77-92, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25859944

RESUMO

Three-dimensional structures of proteins offer an opportunity for the rational design of small molecules to modulate protein-protein interactions. The presence of a well-defined binding pocket on the surface of protein complexes, particularly at their interface, can be used for docking-based virtual screening of chemical libraries. Several approaches have been developed to identify binding pockets that are implemented in programs such as SiteMap, fpocket, and FTSite. These programs enable the scoring of these pockets to determine whether they are suitable to accommodate high-affinity small molecules. Virtual screening of commercial or combinatorial libraries can be carried out to enrich these libraries and select compounds for further experimental validation. In virtual screening, a compound library is docked to the target protein. The resulting structures are scored and ranked for the selection and experimental validation of top candidates. Molecular docking has been implemented in a number of computer programs such as AutoDock Vina. We select a set of protein-protein interactions that have been successfully inhibited with small molecules in the past. Several computer programs are applied to identify pockets on the surface, and molecular docking is conducted in an attempt to reproduce the binding pose of the inhibitors. The results highlight the strengths and limitations of computational methods for the design of PPI inhibitors.


Assuntos
Conformação Proteica/efeitos dos fármacos , Mapeamento de Interação de Proteínas/métodos , Proteínas/química , Bibliotecas de Moléculas Pequenas/química , Sítios de Ligação , Avaliação Pré-Clínica de Medicamentos , Ligantes , Simulação de Acoplamento Molecular , Software , Interface Usuário-Computador
6.
Transplantation ; 89(7): 873-8, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20090571

RESUMO

OBJECTIVE: To investigate the impact of cardiac donor participation in high-risk social behaviors (HRSBs) on recipient survival. METHODS: Retrospective chart review queried cardiac transplantations performed at our institution from August 1994 to November 2007 involving donors known to have engaged in HRSBs. Kaplan-Meier methodology was used to analyze survival rates, and a Cox proportional hazards regression was performed to determine the impact of donor HRSBs on survival. RESULTS: We identified 143 donors with social histories containing the following HRSBs: incarceration (n=69), unprofessional tattoos or piercings (n=44), alternative lifestyle practice (n=11), cocaine use (n=60), heroin smoking (n=6), marijuana use (n=79), oral narcotic abuse (n=20), and intravenous drug use (n=21). At the time of donation, viral screens detected 10 donors who were hepatitis B virus (HBV) positive, 11 donors who were hepatitis C virus (HCV) positive, and no donors who were positive for the HIV. One-year and 5-year survival were 92.2% and 84.4%, respectively. Cox regression analysis found only donor HCV infection to be associated with poorer recipient survival (P=0.14). CONCLUSION: Using cardiac allografts from high-risk donors who are serologically negative for viruses does not seem to impact recipient survival. There is a considerable risk for transmission of HBV and HCV when these are detected by pretransplant screens. However, if pretransplant screening does not discover donor HBV, HCV, or HIV infection, it is unlikely that subclinical disease transmission will occur.


Assuntos
Seleção do Doador , Transplante de Coração/mortalidade , Assunção de Riscos , Comportamento Social , Doadores de Tecidos/provisão & distribuição , Adulto , Piercing Corporal/efeitos adversos , Crime , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/transmissão , Transplante de Coração/efeitos adversos , Hepatite B/diagnóstico , Hepatite B/transmissão , Hepatite C/diagnóstico , Hepatite C/transmissão , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prisioneiros , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Comportamento Sexual , Transtornos Relacionados ao Uso de Substâncias/complicações , Tatuagem/efeitos adversos , Fatores de Tempo , Doadores de Tecidos/psicologia , Transplante Homólogo , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA