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51.
The aim of the study was to determine the effect of β-glucan on the cytotoxicity and genotoxicity of polypectomized patient's fecal water (FW). Polypectomized volunteers (n = 69) were randomly assigned to consume bread with or without β-glucan, for 3 months. FW was collected at the beginning (t = 0), the 30th and 90th day and 2 wk after the intervention. Cytotoxicity and genotoxicity were estimated on Caco-2 cells, using trypan blue exclusion test and comet assay, respectively. Gastrointestinal symptoms were recorded and subjects kept a 3-day food diary at baseline and after completion. Trypan blue exclusion test revealed cell survival of approximately 87% after incubation with FW. The FW samples showed 49% genotoxicity at the baseline. Genotoxicity in the intervention group decreased during the trial reaching statistical significance on the 90th day compared to control. An increase was noticed 2 wk after the trial, but it still remained significantly lower compared to control. Group-specific analysis for β-glucan also revealed significant decrease in the genotoxicity on the 90th day compared to baseline. β-glucan ingestion in polypectomized patients significantly decreased the genotoxicity of their FW. Our findings suggest that β-glucan consumption could possibly provide protection against colon cancer development.  相似文献   
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Objective: Polyunsaturated fatty acids n-3 (PUFA n-3) have shown effects in reducing tumor growth, in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) abundantly present in fish oil (FO). When these fatty acids are provided in the diet, they alter the functions of the cells, particularly in tumor and immune cells. However, the effects of α-linolenic fatty acid (ALA), which is the precursor of EPA and DHA, are controversial. Thus, our objective was to test the effect of this parental fatty acid. Methods: Non-tumor-bearing and tumor-bearing Wistar rats (70 days) were supplemented with 1 g/kg body weight of FO or Oro Inca® (OI) oil (rich in ALA). Immune cells function, proliferation, cytokine production, and subpopulation profile were evaluated. Results: We have shown that innate immune cells enhanced phagocytosis capacity, and increased processing and elimination of antigens. Moreover, there was a decrease in production of pro-inflammatory cytokines (tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6)) by macrophages. Lymphocytes showed decreased proliferation capacity, increased cluster of differentiation 8 (CD8+) subpopulation, and increased TNF-α production. Conclusions: Oil rich in ALA caused similar immune modulation in cancer when compared with FO.  相似文献   
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Reactive lymphoid infiltrates of the skin composed predominantly of gamma‐delta (γδ) T cells are not well described in the literature. Herein we report a case of an otherwise healthy 4‐year‐old male who presented with a waxing and waning papular rash characterized by small, discrete crusted papules spread across his trunk, face and extremities. Clinical evaluation revealed no evidence of systemic disease. Microscopic examination revealed a dermal, perivascular infiltrate of highly atypical lymphocytes with a γδ T cell phenotype, worrisome for primary cutaneous γδ T cell lymphoma. The clinical course, however, was that of a reactive condition and prompted consideration of a diagnosis of pityriasis lichenoides et varioliformis acuta (PLEVA) and lymphomatoid papulosis (LyP). In many ways, this case defies current classification schemes and seems to expand the spectrum of reactive γδ T cell infiltrates of the skin.  相似文献   
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Individuals with sudden unilateral deafness offer a unique opportunity to study plasticity of the binaural auditory system in adult humans. Stimulation of the intact ear results in increased activity in the auditory cortex. However, there are no reports of changes at sub-cortical levels in humans. Therefore, the aim of the present study was to investigate changes in sub-cortical activity immediately before and after the onset of surgically induced unilateral deafness in adult humans. Click-evoked auditory brainstem responses (ABRs) to stimulation of the healthy ear were recorded from ten adults during the course of translabyrinthine surgery for the removal of a unilateral acoustic neuroma. This surgical technique always results in abrupt deafferentation of the affected ear. The results revealed a rapid (within minutes) reduction in latency of wave V (mean pre = 6.55 ms; mean post = 6.15 ms; p < 0.001). A latency reduction was also observed for wave III (mean pre = 4.40 ms; mean post = 4.13 ms; p < 0.001). These reductions in response latency are consistent with functional changes including disinhibition or/and more rapid intra-cellular signalling affecting binaurally sensitive neurons in the central auditory system. The results are highly relevant for improved understanding of putative physiological mechanisms underlying perceptual disorders such as tinnitus and hyperacusis.  相似文献   
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