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111.

Background  

Vestibular schwannoma (acoustic neuroma) most commonly presents with ipsilateral disturbances of acoustic, vestibular, trigeminal and facial nerves. Presentation of vestibular schwannoma with contralateral facial pain is quite uncommon.  相似文献   
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BACKGROUND: Psoriatic plaques have been shown to contain increased levels of proinflammatory cytokines. Serum levels of interleukin (IL)-6, IL-7, IL-8, and interferon (IFN)-gamma have been reported elevated in psoriatic patients. AIM: To evaluate serum cytokine profiles in psoriasis patients by improved enzyme-linked immunosorbent assay (ELISA) technique and to correlate these levels with disease severity. METHODS: We analyzed single serum samples from 10 patients with active untreated psoriasis, two patients with active treated psoriasis, and five healthy volunteers for major T helper type 1 and T helper type 2 cytokines using the LINCOplex ELISA multi-analyte detection system that permits simultaneous detection of multiple cytokines from a single sample. The disease severity, including erythema, induration, scale, and surface area, was assessed. RESULTS: IFN-gamma was markedly elevated in all sera from psoriasis patients, 33.8 +/- 1.3 pg/ml (mean +/- standard error) versus 8 +/- 1.5 pg/ml for normal controls (p < 0.01), and positively correlated with all indices of disease severity (Spearman r > 0.6). IL-8 was also increased in psoriasis patients (24.4 +/- 1.8 pg/ml) versus normal controls (3.6 +/- 1.2 pg/ml) (p < 0.05) and positively correlated with the degree of erythema (Spearman r > 0.6). Mean IL-12 levels were decreased in sera from psoriasis patients (8.5 +/- 1.2 pg/ml) compared with normal controls (42.2 +/- 5.3 pg/ml) (p < 0.01). Also, serum IL-10 levels were below detection levels in psoriatics compared with controls (6.4 +/- 1.3 pg/ml). CONCLUSIONS: This new ELISA system allowed rapid and reliable detection of numerous cytokines in single serum samples from patients with psoriasis. We observed that IFN-gamma and IL-8 cytokines were elevated in psoriatics and correlated with parameters of disease severity while IL-10 and IL-12 were decreased.  相似文献   
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Laboratory studies were performed to explore the effects of host-plant quality on the vulnerability of Plutella xylostella to Bacillus thuringiensis. P. xylostella were kept on different host plants, including Brassica pekinensis (Chinese cabbage) cv. Hero, Brassica oleracea var. botrytis (cauliflower) cv. Royal, and B. oleracea var. capitata (common cabbage) cv. Globe Master (white cabbage) and cv. Red Dynasty (red cabbage) for at least two generations. These host plants are considered as the high (Chinese cabbage), intermediate (cauliflower and white cabbage) and low-quality (red cabbage) hosts for P. xylostella. The vulnerability of the pest larvae was then tested using two formulation of B. thuringiensis var. kurstaki, including Biolarv® and Biolep®. The results demonstrated that the susceptibility of P. xylostella to B. thuringiensis was influenced by host-plant quality. Indeed, B. thuringiensis acted better on the pest fed on the low-quality host plant compared with that on the high-quality host plant. The interaction between the pathogen and plant quality/resistance resulted in more mortality of the pest larvae, implying a synergistic effect. From a pest management viewpoint, these findings may be promising for the integration of the pathogen and the low-quality/partially resistant host plants against P. xylostella in field studies.  相似文献   
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Alteration of the p53 tumor suppressor gene is the most common genetic abnormality in human cancer. In breast cancer, depending on the stage of disease and method of detection, mutation rates of 25-60% have been observed. Multiple mutations of p53 gene in the same tumor however, are rarely reported. In this study we explored the frequency of multiple mutations of p53 gene in mammary carcinoma in a cohort of south Florida patients. Three hundred eighty-four cases of primary breast cancer diagnosed between 1984 and 1986 at the University of Miami, Jackson Medical Center were subjects of this study. Sequence analysis of exons 5 through 8 of p53 was performed on cloned PCR-amplified DNA of formalin-fixed, paraffin-embedded tumors. Two hundred thirty-four of 384 breast cancers (61%) had p53 mutation. Of those, 36 tumors showed more than one mutation; 31 tumors had two mutations, three showed three, one tumor had five mutations, and one case carried six mutations. The majority of mutations were missense (43) followed by silent (35); and most occurred within a single exon. Our study suggests that multiple mutations of p53 suppressor gene in breast cancer are more common than currently believed.  相似文献   
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Tissue engineering has yet to reach its ideal goal, i.e. creating profitable off-the-shelf tissues and organs, designing scaffolds and three-dimensional tissue architectures that can maintain the blood supply, proper biomaterial selection, and identifying the most efficient cell source for use in cell therapy and tissue engineering. These are still the major challenges in this field. Regarding the identification of the most appropriate cell source, aging as a factor that affects both somatic and stem cells and limits their function and applications is a preventable and, at least to some extents, a reversible phenomenon. Here, we reviewed different stem cell types, namely embryonic stem cells, adult stem cells, induced pluripotent stem cells, and genetically modified stem cells, as well as their sources, i.e. autologous, allogeneic, and xenogeneic sources. Afterward, we approached aging by discussing the functional decline of aged stem cells and different intrinsic and extrinsic factors that are involved in stem cell aging including replicative senescence and Hayflick limit, autophagy, epigenetic changes, miRNAs, mTOR and AMPK pathways, and the role of mitochondria in stem cell senescence. Finally, various interventions for rejuvenation and geroprotection of stem cells are discussed. These interventions can be applied in cell therapy and tissue engineering methods to conquer aging as a limiting factor, both in original cell source and in the in vitro proliferated cells.  相似文献   
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The biochemical and molecular responses of five commercially well-known pomegranate cultivars to severe water stress were studied. The cultivars were subjected to 14-day water stress by withholding irrigation, followed by re-watering for 7 days. Results showed clear differences in metabolites contents and activities of antioxidant enzymes among various pomegranate cultivars during severe water stress and recovery. According to our results, increased accumulation of proline in pomegranate was not related to osmotic adjustment during severe water stress. Except for ‘Ghojagh’, leaves grown under severe water stress conditions showed symptoms of oxidative stress such as reduced chlorophyll concentration. The improved performance of ‘Ghojagh’ under drought stress may be associated with an efficient osmotic adjustment. The up- or down regulated expression of cytosolic glutathione reductase (cytosolic GR) and glutathione peroxidase were observed under drought conditions. Moreover, the suppressed expression of cytosolic GR was also noted. Comparatively, ‘Rabab’ exhibited higher antioxidant capacity and an efficient ROS-scavenging mechanism under drought stress. Lower levels of membrane lipid peroxidation in ‘Ghojagh’ and ‘Rabab’ under drought stress and the marked reduction of malondialdehyde concentration after re-watering represents that these cultivars have a good tolerance to drought stress. As a first step towards the study of the biochemical and molecular responses of pomegranate plants to water stress, this research provides new information into the mechanisms of drought tolerance in the plants.  相似文献   
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Magnesium (Mg2+) potentiated the anti-vesicular stomatitis virus (VSV) activity of poly r(A-U) or poly r(G-C) and the anti-HIV-1 activity of poly r(A-U). Mg2+ did not affect the anti-VSV activity of poly (rI).poly (rC), poly (dA-dT).poly (dA-dT) or poly (dG-dC).poly (dG-dC). Modulation of one or more nuclear (nucleolar) processes of the host cell may be responsible for the synergistic antiviral activity.  相似文献   
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