Low power laser radiation at 685 nm stimulates stem-cell proliferation rate in Dugesia tigrina during regeneration

Today's scientific interest in tissue engineering for organ transplantations and regeneration from stem cells, allied with recent observations on biostimulation of tissues and cells by laser radiation, stands as a strong motivation for the present work, in which we examine the effects of the low power laser radiation onto planarians under regenerative process. To investigate those effects, a number of 60 amputated worms were divided in three study groups: a control group and two other groups submitted to daily 1 and 3 min long laser treatment sections at similar to 910 W/m(2) power density. A 685 nm diode laser with 35 mW optical power was used. Samples were sent to histological analysis at the 4th, the 7th and the 15th (lays after amputation. A remarkable increase in stem cells counts for the fourth day of regeneration was observed when the regenerating worms was stimulated by the laser radiation. Our findings encourage further research works on the influence of optical radiation onto stem cells and tissue regeneration. (c) 2005 Elsevier B.V. All rights reserved.

A phase III randomized double-blind placebo-controlled clinical trial to determine the efficacy of low level laser therapy for the prevention of oral mucositis in patients undergoing hematopoietic cell transplantation

Introduction Oral mucositis (OM) is a significant early complication of hematopoietic cell transplantation (HCT). This phase III randomized double-blind placebo-controlled study was designed to compare the ability of 2 different low level GaAlAs diode lasers (650 nm and 780 nm) to prevent oral mucositis in HCT patients conditioned with chemotherapy or chemoradiotherapy.Materials and methods Seventy patients were enrolled and randomized into 1 of 3 treatment groups: 650 nm laser, 780 nm laser or placebo. All active laser treatment patients received daily direct laser treatment to the lower labial mucosa, right and left buccal mucosa, lateral and ventral surfaces of the tongue, and floor of mouth with energy densities of 2 J/cm(2). Study treatment began on the first day of conditioning and continued through day +2 post HCT. Mucositis and oral pain was measured on days 0, 4, 7, 11, 14, 18, and 21 post HCT.Results the 650 nm wavelength reduced the severity of oral mucositis and pain scores. Low level laser therapy was well-tolerated and no adverse events were noted.Discussion While these results are encouraging, further study is needed to truly establish the efficacy of this mucositis prevention strategy. Future research needs to determine the effects of modification of laser parameters (e.g., wavelength, fluence, repetition rate of energy delivery, etc.) on the effectiveness of LLE laser to prevent OM.

Effect of the bone marrow cell transplantation on elevated plus-maze performance in hippocampal-injured mice

Several reports have shown that the hippocampus plays an important role in different aspects of the emotional control. There is evidence that lesions in this structure cause behavioral disinhibition, with reduction of reactions expressing fear and anxiety. Thus, to portray the aptitude of cell therapy to abrogate injuries of hippocampal tissue, we examined the behavioral effects of bone marrow mononuclear cells (BMMCs) transplantation on C57BL/6 mice that had the hippocampus damaged by electrolytic lesion. For this purpose, mice received, seven days after bilateral electrolytic lesion in the dorsal hippocampus, culture medium or BMMCs expressing the enhanced green fluorescent protein (EGFP) transgene. One week after transplantation, animals were tested in the elevated plus-maze (EPM). On the whole, three assessment sessions in the EPM were carried out, with seven days separating each trial. Thirty-five days after the induction of injury, mice were sacrificed and their brains removed for immunohistochemistry. The behavioral evaluation showed that the hippocampal lesion caused disinhibition, an effect which was slightly lessened, from the second EPM test, in transplanted subjects. On the other hand, immunohistochemical data revealed an insignificant presence of EGFP+ cells inside the brains of injured mice. In view of such scenario, we hypothesized that the subtle rehabilitation of the altered behavior might be a result from a paracrine effect from the transplanted cells. This might have been caused by the release of bioactive factors capable of boosting endogenous recuperative mechanisms for a partial regaining of the hippocampal functions. © 2013 Elsevier B.V.

Stem cell factor estimula células da musculatura lisa da traqueia a produzir TGF-β, FGF-2 E CCL3/MIP-1α

Pós-graduação em Ciências Fisiológicas - FOA

Função cardíaca de cães submetidos ao transplante autólogo de células-tronco hematopoiéticas em dois modelos experimentais de cardiomiopatia

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Padronização da coleta e quantificação de células-tronco hematopoéticas no sangue do cordão umbilical de cães

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Peripheral Blood Mononuclear Phagocytes From Patients With Chronic Periodontitis Are Primed for Osteoclast Formation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Novel Chemically Modified Bacterial Cellulose Nanocomposite as Potential Biomaterial for Stem Cell Therapy Applications

Bacterial cellulose (BC) has become established as a remarkably versatile biomaterial and can be used in a wide variety of applied scientific applications, especially for medical devices. In this work, the bacterial cellulose fermentation process is modified by the addition of hyaluronic acid and gelatin (1% w/w) to the culture medium before the bacteria is inoculated. Hyaluronic acid and gelatin influence in bacterial cellulose was analyzed using Transmission Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). Adhesion and viability studies with human dental pulp stem cells using natural bacterial cellulose/hyaluronic acid as scaffolds for regenerative medicine are presented for the first time in this work. MTT viability assays show higher cell adhesion in bacterial cellulose/gelatin and bacterial cellulose/ hyaluronic acid scaffolds over time with differences due to fiber agglomeration in bacterial cellulose/gelatin. Confocal microscopy images showed that the cell were adhered and well distributed within the fibers in both types of scaffolds.

Phenotypic and functional evaluations of peripheral blood monocytes from chronic-form paracoccidioidomycosis patients before and after treatment

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

O papel da proteína TET2 no enriquecimento do DNA genômico em 5-hidroximetilcitosina em lesões elanocíticas pré-malignas e pré-metastáticas com fenótipo stem cell-like

Durante a transformação maligna dos melanócitos, padrões de metilação do DNA encontram-se alterados, afetando a expressão gênica. As citosinas metiladas (5mC) podem ser hidroxiladas pelas dioxigenases dependentes de 2-oxoglutarato e Fe(II), Tet1, 2 e 3, resultando na formação de 5-hidroximetilcitosina (5hmC) (Globisch et al., 2010; Ko et al., 2010). A 5hmC pode agir tanto como um produto intermediário na desmetilação ativa do DNA quanto na desmetilação passiva ao longo de sucessivas replicações, o que pode contribuir com a dinâmica da metilação do DNA (Tahiliani et al., 2009). Além disso, demonstrou-se que Tet1 e Tet2 são expressas em células tronco embrionárias (Ito et al., 2010) e que 5hmC desempenha importante papel na manutenção e diferenciação destas células (Koh et al., 2011). No entanto, o papel da 5hmC e das proteínas Tet tanto na fisiologia normal quanto em doenças como o câncer ainda não está claro. Utilizando um modelo linear de progressão do melanoma, observamos aumento na expressão gênica de Tet1 nas linhagens celulares correspondendo a melanócitos pré-malignos (4C) e células de melanoma não metastático (4C11-), comparado a melanócitos não tumorigênicos (melan-a) e células de melanoma metastático (4C11+). Em relação à expressão proteica, há um aumento da expressão de Tet1 nas linhagens 4C e 4C11+, o que pode ser relacionado às fases de transição epitélio-mesênquima (EMT) e mesênquima-epitélio (MET), respectivamente. Além disso, constatamos aumento na expressão gênica e proteica de Tet2 na linhagem metastática 4C11+, o que pode indicar diferenças funcionais entre as proteínas Tet1 e Tet2. Também verificamos aumento significativo do conteúdo de 5hmC na linhagem 4C11+, o que se correlaciona com maior expressão gênica e proteica de Tet2. Por fim, linhagens humanas de melanoma metastático menos agressivas apresentaram aumento significativo na expressão dos genes TET1 ...