In Situ Confocal Raman Mapping Study of a Single Ti-Assisted ZnO Nanowire

In this work, we succeeded in preparing in-plane zinc oxide nanowires using a Ti-grid assisted by the chemical vapor deposition method. Optical spatial mapping of the Confocal Raman spectra was used to investigate the phonon and geometric properties of a single ZnO nanowire. The local optical results reveal a red shift in the non-polar E2 high frequency mode and width broadening along the growth direction, reflecting quantum-confinement in the radial direction

Alterações oculares por uso sistêmico de alfa-interferon em pacientes com hepatite C

PURPOSE: To describe ocular (specially fundoscopic) changes due to systemic alpha-interferon (IFN) therapy in patients with hepatitis C. This is a prospective, descriptive and observational (non-interventional) study, and its results are preliminary. METHODS: Patients were selected with indication of alpha-interferon therapy for hepatitis C. They underwent ocular examinations before therapy and 1, 3, 6 and 12 months after starting the therapy. HIV patients and those who had a history of previous treatment with alpha-interferon were excluded from the study, but examined. RESULTS: Fifty-one patients were selected from November 1999 to June 2000. The male-to-female ratio was 1.55. The age average was 47 years. The best corrected visual acuity ranged from 20/15 to 20/40. Most of the symptomatic patients complained of foreign body sensation in the eyes, which became more tolerable with time. Complaints comprised flu-like symptoms, joint pain, depression, headache, and general weakness. Ocular findings related to alpha-interferon were: cotton wool spots (3 eyes) and intraretinal hemorrhage (1 eye). One patient died during the study, due to another disease not related to hepatitis, and one patient refused to be examined. CONCLUSIONS: There are retinal vascular changes due to systemic alpha-interferon for hepatitis C. There are no studies in our country describing ocular changes in patients with hepatitis C on therapy with alpha-interferon. General physicians and specially gastroenterologists should pay special attention to this problem, and refer these patients to the ophthalmologist in order to determine and follow any lesion that may be related to the use of this drug.OBJETIVO: Avaliar alterações oculares (em especial lesões fundoscópicas) em pacientes com hepatite C tratados com alfa-interferon (IFN). MÉTODOS: Estudo prospectivo, descritivo e observacional de pacientes com hepatite C do serviço de Gastroenterologia da UNIFESP com indicações de uso de alfa-interferon entre novembro de 1999 e junho de 2000. Esses pacientes foram submetidos a exame oftalmológico completo antes e 1, 3, 6 e 12 meses após o início do tratamento. Pacientes HIV positivos, ou com exposição prévia à droga foram excluídos. RESULTADOS: De um total de 51 pacientes selecionados, 31 foram acompanhados. A relação masculino-feminino foi de 1,55, e a média de idade de 47 anos. A acuidade visual corrigida variou de 20/15 a 20/40. Vinte e dois por cento dos pacientes queixaram-se de sensação de corpo estranho, principalmente nos dois primeiros meses de terapia. Queixas gerais foram: artralgia, cefaléia, depressão, fraqueza muscular. Achados oculares foram: hemorragia retiniana (um olho) e exsudatos moles (três olhos), todos assintomáticos. Em um paciente com história pregressa de tratamento com interferon, observou-se presença de hemorragia vítrea, exsudatos duros e moles e tortuosidade vascular. Um paciente faleceu durante o tratamento por infarto cardíaco. CONCLUSÕES: Existem alterações oculares por uso sistêmico de alfa-interferon. Não existem estudos no nosso país descrevendo essas alterações. Médicos clínicos gerais e gastroenterologistas devem prestar atenção a esse tipo de problema, e encaminhar os pacientes a um serviço de oftalmologia para acompanhamento paralelo.Universidade Federal de São Paulo (UNIFESP) Departamento de OftalmologiaUniversidade Federal de São Paulo (UNIFESP)UNIFESP, Depto. de OftalmologiaUNIFESPSciEL

Bmi-1 Regulates Snail Expression and Promotes Metastasis Ability in Head and Neck Squamous Cancer-Derived ALDH1 Positive Cells

Recent studies suggest that ALDH1 is a putative marker for HNSCC-derived cancer stem cells. However, the regulation mechanisms that maintain the stemness and metastatic capability of HNSCC-ALDH1+ cells remain unclear. Initially, HNSCC-ALDH1+ cells from HNSCC patient showed cancer stemness properties, and high expression of Bmi1 and Snail. Functionally, tumorigenic properties of HNSCC-ALDH1+ cells could be downregulated by knockdown of Bmi-1. Overexpression of Bmi-1 altered in expression property ALDH1− cells to that of ALDH1+ cells. Furthermore, knockdown of Bmi-1 enhanced the radiosensitivity of radiation-treated HNSCC-ALDH1+ cells. Moreover, overexpression of Bmi-1 in HNSCC-ALDH1− cells increased tumor volume and number of pulmonary metastatic lesions by xenotransplant assay. Importantly, knock-down of Bmi1 in HNSCC-ALDH1+ cells significantly decreased distant metastases in the lungs. Clinically, coexpression of Bmi-1/Snail/ALDH1 predicted the worst prognosis in HNSCC patients. Collectively, our data suggested that Bmi-1 plays a key role in regulating Snail expression and cancer stemness properties of HNSCC-ALDH1+ cells

Serum repressing efflux pump CDR1 in Candida albicans

BACKGROUND: In the past decades, the prevalence of candidemia has increased significantly and drug resistance has also become a pressing problem. Overexpression of CDR1, an efflux pump, has been proposed as a major mechanism contributing to the drug resistance in Candida albicans. It has been demonstrated that biological fluids such as human serum can have profound effects on antifungal pharmacodynamics. The aim of this study is to understand the effects of serum in drug susceptibility via monitoring the activity of CDR1 promoter of C. albicans. RESULTS: The wild-type C. albicans cells (SC5314) but not the cdr1/cdr1 mutant cells became more susceptible to the antifungal drug when the medium contained serum. To understand the regulation of CDR1 in the presence of serum, we have constructed CDR1 promoter-Renilla luciferase (CDR1p-RLUC) reporter to monitor the activity of the CDR1 promoter in C. albicans. As expected, the expression of CDR1p-RLUC was induced by miconazole. Surprisingly, it was repressed by serum. Consistently, the level of CDR1 mRNA was also reduced in the presence of serum but not N-acetyl-D-glucosamine, a known inducer for germ tube formation. CONCLUSION: Our finding that the expression of CDR1 is repressed by serum raises the question as to how does CDR1 contribute to the drug resistance in C. albicans causing candidemia. This also suggests that it is important to re-assess the prediction of in vivo therapeutic outcome of candidemia based on the results of standard in vitro antifungal susceptibility testing, conducted in the absence of serum