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1.
J Ophthalmol ; 2019: 1760742, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31531233

RESUMO

Purpose: To compare visual performance and visual quality outcomes after phacoemulsification with two different clear corneal incision (CCI) distances anterior to the limbus in senile cataract patients. Methods: Retrospective case series. Patients who had undergone phacoemulsification were divided into two groups according to the CCI distances anterior to the limbus. The CCI distances in group A range from 1 mm to 1.5 mm, while those in group B range from 0.5 mm to 1 mm. The visual acuity, refraction, surgically induced astigmatism (SIA), corneal aberrations, anterior segment parameters, and subjective vision quality were evaluated. Results: This study enrolled 54 eyes, with 27 eyes per group. Both groups had significant improvement in postoperative uncorrected visual acuity (UCVA) and corrected distance visual acuity (CDVA) (P < 0.05). There were no statistically significant between-group differences in postoperative UDVA, CDVA, SIA, corneal aberrations, anterior segment parameters, or VF-QOL questionnaire performance (P > 0.05). Conclusions: The phacoemulsification with CCI distances ranging from 0.5 mm to 1.5 mm is an effective and safe therapy to senile cataract. The CCI distance anterior to the limbus that ranges from 0.5 mm to 1.5 mm is recommended for routine phacoemulsification.

2.
Adv Mater ; 30(45): e1804218, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30198162

RESUMO

Composition and phase specific 2D transition metal dichalogenides (2D TMDs) with a controlled electronic and chemical structure are essential for future electronics. While alloying allows bandgap tunability, heterostructure formation creates atomically sharp electronic junctions. Herein, the formation of lateral heterostructures from quaternary 2D TMD alloys, by thermal annealing, is demonstrated. Phase separation is observed through photoluminescence and Raman spectroscopy, and the sharp interface of the lateral heterostructure is examined via scanning transmission electron microscopy. The composition-dependent transformation is caused by existence of miscibility gap in the quaternary alloys. The phase diagram displaying the miscibility gap is obtained from the reciprocal solution model based on density functional theory and verified experimentally. The experiments show direct evidence of composition-driven heterostructure formation in 2D atomic layer systems.

3.
Mol Vis ; 24: 340-352, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29769799

RESUMO

Purpose: To investigate the role of placental growth factor (PGF) in the epithelial-mesenchymal transition (EMT) of ARPE-19 cells under hypoxia, and whether the NF-κB signaling pathway is involved in this process. Methods: ARPE-19 cells were treated in five groups: a control group, hypoxia group, PGF group, hypoxia+PGF group, and NF-κB-blocked group. A chemical hypoxia model was established in the ARPE-19 cells by adding CoCl2 to the culture medium. The morphological changes after treatment were observed. The proliferation rates were measured with 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. The migration abilities were measured with scratch assay. The EMT biomarkers were measured with quantitative real-time PCR (qRT-PCR), western blotting, and immunofluorescence. The relative protein expression of components of the NF-κB signaling pathway was measured with western blotting and immunofluorescence. Results: Cells treated with PGF under hypoxia exhibited morphological changes consistent with the transition from an epithelial to a mesenchymal phenotype. In the ARPE-19 cells, exogenous PGF under hypoxia increased the proliferation rate compared to the rate under hypoxia alone (p<0.05) and increased the migration rate (p<0.05). Treatment of hypoxia-exposed cells with PGF caused decreased expression of the epithelial biomarkers E-cadherin and ZO-1 (both p<0.05) and increased expression of the mesenchymal marker α-SMA (p<0.05) by enhancing the phosphorylation of NF-κB p65 of the total protein, promoting the translocation of p65 to the nucleus, and inducing the degradation of IκB-α (a negative regulator of the NF-κB pathway) in the ARPE-19 cells. Additionally, the effect of PGF-induced EMT in the ARPE-19 cells under hypoxia was counteracted with BAY 11-7082 (a selective NF-κB inhibitor). Conclusions: Exogenous PGF promotes EMT-like changes in ARPE-19 cells under hypoxia by activating the NF-κB signaling pathway. The study results suggest that PGF may play a role in scar formation in neovascular age-related macular degeneration (AMD) and that the inhibition of PGF may be a promising target for the prevention and treatment of AMD.


Assuntos
Cobalto/farmacologia , Células Epiteliais/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fator de Crescimento Placentário/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA/genética , Actinas/genética , Actinas/metabolismo , Antígenos CD , Caderinas/genética , Caderinas/metabolismo , Hipóxia Celular , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Regulação da Expressão Gênica , Humanos , Inibidor de NF-kappaB alfa/genética , Inibidor de NF-kappaB alfa/metabolismo , Nitrilos/farmacologia , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/metabolismo , Sulfonas/farmacologia , Fator de Transcrição RelA/agonistas , Fator de Transcrição RelA/antagonistas & inibidores , Fator de Transcrição RelA/metabolismo , Proteína da Zônula de Oclusão-1/genética , Proteína da Zônula de Oclusão-1/metabolismo
4.
Nan Fang Yi Ke Da Xue Xue Bao ; 38(12): 1492-1497, 2018 Dec 30.
Artigo em Chinês | MEDLINE | ID: mdl-30613019

RESUMO

OBJECTIVE: To determine the safe distance range of clear corneal incision (CCI) from the corneal limbus and how different CCI sites affect surgery efficacy and anterior segment parameters in patients undergoing phacoemulsification. METHODS: This retrospective case-control study was conducted in 44 patients (44 eyes) undergoing phacoemulsification and IOL implantation. The patients were divided into two groups with CCI distances ranging from 1 mm to 1.5 mm (group A, n= 22) and from 0.5 mm to 1.0 mm (group B, n= 22). The visual acuity, surgically induced astigmatism (SIA), corneal aberration, and anterior segment parameters were analyzed. RESULTS: Compared with the preoperative data, all the patients showed significant improvements in the postoperative uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), anterior chamber depth (ACD), and anterior chamber angle (ACA) after the surgery (P < 0.05). No significant differences were found between the two groups in postoperative UCVA, BCVA, SIA, total corneal aberration RMS, lower- and higher-order aberration RMS, spherical aberration (Z40), horizontal three leaf clover (Z33), vertical three leaf clover(Z3-3), horizontal coma(Z31), vertical coma(Z3-1), ACD, ACA, anterior chamber volume, or central corneal thickness (P>0.05). CONCLUSIONS: Phacoemulsification is an effective therapy for cataract with a CCI distance range either of 1-1.5 mm or 0.5-1.0 mm. These two CCI distance ranges produce no significant differences in the visual quality following phacoemulsification, indicating that a CCI distance range of 0.5-1.5 mm can be safe for phacoemulsification.


Assuntos
Córnea/cirurgia , Implante de Lente Intraocular , Facoemulsificação/métodos , Segmento Anterior do Olho , Astigmatismo/etiologia , Estudos de Casos e Controles , Humanos , Limbo da Córnea , Facoemulsificação/efeitos adversos , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Ferida Cirúrgica , Resultado do Tratamento , Acuidade Visual
5.
Exp Ther Med ; 14(4): 3868-3873, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29042994

RESUMO

The aim of the present study was to investigate whether low-dose priming radiation induces antitumor immunity that can be augmented by the modulation of natural killer (NK) cell and cytokine activity using a mouse tumor model. Walker-256 cells were injected into the right flank of male BALB/c mice. At 7 days after inoculation, mice were divided into three groups, including group 1,2,3. In group 1 the mice were without radiation, in group 2 the mice were received 2 Gy radiation only, and in group 3 the mice were radiated with a priming dose of 75 mGy followed by 2 Gy radiation after 24 h. On day 21 following the radiation, the tumors were removed and the tumor index (tumor weight as a percentage of body weight) was calculated. At 1, 7, 14 and 21 days following the 2 Gy radiation, mouse splenocytes were isolated to analyze the NK activity and measure the production of the cytokines interleukin-1ß, interferon-γ and tumor necrosis factor-α by ELISA. Apoptosis was also measured by flow cytometry. The results demonstrated that priming radiation significantly delayed the tumor growth and prolonged the median survival time to 38 days compared with the 31-day survival in the 2 Gy radiation group. The percentage of apoptotic cells was significantly higher in the mice that received 75 mGy + 2 Gy radiation compared with that in the mice that received 2 Gy alone; by contrast, mice that were not irradiated exhibited a relatively low level of apoptosis. The primed mice had a higher level of NK activity as compared with the mice exposed to 2 Gy radiation only or mice that were not irradiated. Furthermore, cytokine expression remained at a higher level in mice receiving priming dose of radiation compared that in the mice receiving only 2 Gy radiation. In conclusion, the results indicated that low-dose priming X-ray radiation may enhance the NK activity and the levels of cytokines, and that the immune response serves an important role in anticancer therapy, including radiotherapy.

6.
Ther Innov Regul Sci ; 50(6): 710-717, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30231747

RESUMO

Adaptive designs have generated great interest in the clinical trial community as a result of their versatility and efficiency. Recently, the Center for Devices and Radiological Health (CDRH) at the US Food and Drug Administration (FDA) surveyed all adaptive design applications submitted between 2007 and May 2013 for regulatory review. In this paper, we discuss the overall results and findings that emerged from an in-depth examination of the submissions. We summarize the current status of adaptive designs used in medical device studies. We also identify some of the lessons learned and common pitfalls that we encountered in our review of the designs.

7.
J Biopharm Stat ; 21(5): 938-53, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21830924

RESUMO

Challenging statistical issues often arise in the design and analysis of clinical trials to assess safety and effectiveness of medical devices in the regulatory setting. The use of Bayesian methods in the design and analysis of medical device clinical trials has been increasing significantly in the past decade, not only due to the availability of prior information, but mainly due to the appealing nature of Bayesian clinical trial designs. The Center for Devices and Radiological Health at the Food and Drug Administration (FDA) has gained extensive experience with the use of Bayesian statistical methods and has identified some important issues that need further exploration. In this article, we discuss several topics relating to the use of Bayesian statistical methods in medical device trials, based on our experience and real applications. We illustrate the benefits and challenges of Bayesian approaches when incorporating prior information to evaluate the effectiveness and safety of a medical device. We further present an example of a Bayesian adaptive clinical trial and compare it to a traditional frequentist design. Finally, we discuss the use of Bayesian hierarchical models for multiregional trials and highlight the advantages of the Bayesian approach when specifying clinically relevant study hypotheses.


Assuntos
Ensaios Clínicos como Assunto/métodos , Aprovação de Equipamentos/legislação & jurisprudência , Segurança de Equipamentos/estatística & dados numéricos , Equipamentos e Provisões/estatística & dados numéricos , Regulamentação Governamental , Modelos Estatísticos , Estudos Multicêntricos como Assunto/estatística & dados numéricos , Angioplastia/métodos , Teorema de Bayes , Ensaios Clínicos como Assunto/legislação & jurisprudência , Ensaios Clínicos como Assunto/estatística & dados numéricos , Segurança de Equipamentos/tendências , Humanos , Estudos Multicêntricos como Assunto/métodos , Estudos Multicêntricos como Assunto/tendências , Infarto do Miocárdio/cirurgia , Infarto do Miocárdio/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/tendências , Projetos de Pesquisa , Stents , Resultado do Tratamento , Estados Unidos
8.
Pharmacogenomics ; 7(3): 299-309, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16610941

RESUMO

RNA interference (RNAi) high-throughput screening (HTS) experiments carried out using large (>5000 short interfering [si]RNA) libraries generate a huge amount of data. In order to use these data to identify the most effective siRNAs tested, it is critical to adopt and develop appropriate statistical methods. To address the questions in hit selection of RNAi HTS, we proposed a quartile-based method which is robust to outliers, true hits and nonsymmetrical data. We compared it with the more traditional tests, mean +/- k standard deviation (SD) and median +/- 3 median of absolute deviation (MAD). The results suggested that the quartile-based method selected more hits than mean +/- k SD under the same preset error rate. The number of hits selected by median +/- k MAD was close to that by the quartile-based method. Further analysis suggested that the quartile-based method had the greatest power in detecting true hits, especially weak or moderate true hits. Our investigation also suggested that platewise analysis (determining effective siRNAs on a plate-by-plate basis) can adjust for systematic errors in different plates, while an experimentwise analysis, in which effective siRNAs are identified in an analysis of the entire experiment, cannot. However, experimentwise analysis may detect a cluster of true positive hits placed together in one or several plates, while platewise analysis may not. To display hit selection results, we designed a specific figure called a plate-well series plot. We thus suggest the following strategy for hit selection in RNAi HTS experiments. First, choose the quartile-based method, or median +/- k MAD, for identifying effective siRNAs. Second, perform the chosen method experimentwise on transformed/normalized data, such as percentage inhibition, to check the possibility of hit clusters. If a cluster of selected hits are observed, repeat the analysis based on untransformed data to determine whether the cluster is due to an artifact in the data. If no clusters of hits are observed, select hits by performing platewise analysis on transformed data. Third, adopt the plate-well series plot to visualize both the data and the hit selection results, as well as to check for artifacts.


Assuntos
Interferência de RNA/fisiologia , Análise por Conglomerados , Interpretação Estatística de Dados , Avaliação Pré-Clínica de Medicamentos/métodos , Reações Falso-Positivas , Biblioteca Gênica , Humanos
9.
J Am Chem Soc ; 125(39): 11832-3, 2003 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-14505401

RESUMO

Using natural polypeptide protamines as the illustrating example, we observed the phase transfer of biological polyions at polarized interfaces between two immiscible electrolyte solutions (ITIES) for the first time by micropipet voltammetry. Analysis of the limiting currents indicates that each protamine carries 20 positive charges as expected from the number of arginine residues in the molecule. Also, it was shown that the shape of the voltammograms is limited by the interfacial transfer of protamines. Coupling of the transfer reactions with interfacial adsorption/desorption of protamines was also observed. ITIES will serve as a basis of amperometric sensors for biological macromolecules and also as a model for understanding potential-driven membrane transport of these molecules.


Assuntos
Peptídeos/química , Protaminas/química , Eletroquímica/métodos
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