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41.
Recently, we and others showed that the components of green tea may be useful cancer chemopreventive agents. It has been suggested that (-)-epigallocatechin-3-gallate (EGCG), the major constituent in green tea, may possess antitumor-promoting and/or anticarcinogenic effects in rodent tumor bioassay systems. During the chemical analysis of various green tea products, we found a traditionally preserved preparation of green tea used by tribes in the Himalayan region of Sikkim, India that was rich in EGCG. EGCG was isolated from this tea product, and its inhibitory effects were evaluated against the binding of topically applied 3H-labeled polycyclic aromatic hydrocarbons (PAHs) to epidermal DNA and 12-O-tetradecanoylphorbol-13-acetate (TPA) caused induction of epidermal ornithine decarboxylase (ODC) activity in Sencar mice, the short-term markers of tumor initiation and tumor promotion, respectively. Preapplication of EGCG resulted in significant inhibition (p less than 0.05) in the binding of [3H]PAH to epidermal DNA. Similarly, the topical application of EGCG resulted in significant inhibition (p less than 0.005) in TPA-caused induction of epidermal ODC activity. In further studies, we assessed the anti-skin tumor-initiating effect of EGCG in Sencar mice in an initiation-promotion protocol. The application of EGCG before challenge with 7,12-dimethylbenz[a]anthracene as tumor initiator resulted in significant reduction both in percentage of mice with tumors and number of tumors per mouse compared with a non-EGCG-pretreated group of animals. The results of the present study suggest that the green tea preparation from Sikkim may be a good source for the isolation of EGCG and that this compound may have significant potential as a cancer chemopreventive agent.  相似文献   
42.
Sturge-Weber syndrome is a rare neurocutaneous disorder characterized by a facial nevus flammeus and extensive angiomatous changes involving the leptomeninges, the dura, and vessels of the gray and white matter. Oculodermal melanocytosis is characterized by hyperpigmentation of the facial skin in the distribution of the ophthalmic, maxillary, and occasionally mandibular division of the trigeminal nerve.  相似文献   
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Extracts of plants have been widely evaluated for possible antiproliferative and anticarcinogenic properties. The antiproliferative activity of ethanolic extract of Boerhaavia diffusa, a plant used in traditional medicine, was evaluated in several cells. It inhibited T cell mitogen phytohemagglutinin and concanavalin A-stimulated proliferation of human peripheral blood mononuclear cells (PBMC). It also inhibited purified protein derivative antigen-stimulated PBMC proliferation and human mixed lymphocyte culture. In addition, B. diffusa extract inhibited the growth of several cell lines of mouse and human origin, such as mouse macrophage cells (RAW 264.7), human macrophage cells (U937), human monocytic cells (THP-1), mouse fibroblast cells (L929), human embryonic kidney cells (HEK293), mouse liver cells (BNLCL.2), African green monkey kidney cells (COS-1), mouse lymphoma cells (EL-4), human erythroleukemic cells (K562), and human T cells (Jurkat). The present study has demonstrated the antiproliferative potential of ethanolic extract of B. diffusa in vitro.  相似文献   
45.
Pain associated with Herpes Zoster (HZ) and Post-herpetic Neuralgia (PHN) has been a challenging task to manage with ease. Topical aspirin dissolved in chloroform is an effective means of reducing pain due to HZ and PHN in most patients. The locus of pain origin and analgesia induced by topical aspirin is supposed to be at cutaneous free nerve ending pain receptors. The present study was conduced in fifty two patients of HZ and PHN. Pain intensity before and after the application of drug was measured with help of Sort Form McGill Pain Questionnaire (SE-MPQ). Most of the patients experienced relief of pain within 1-5 minutes after the aspirin-chloroform application. Maximum relief was achieved in about 30-40 minutes and persisted for 5-6 hrs. In the beginning 3-4 applications were required but frequency decreased gradually as the pain abated.  相似文献   
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The objective of this study was to determine the proliferative responses of peripheral blood lymphocytes of ocular antigens like retinal S-antigen, peptides M and G of S-antigen, yeast histone H3 peptide 106–121 homologous to peptide M and peptide R16 of interphotoreceptor retinoid binding protein (IRBP) in children with juvenile chronic arthritis (JCA). We have studied the in vitro proliferative response of peripheral blood lymphocytes from 41 patients with JCA (10 with and 31 without uveitis) and 23 healthy controls against the above antigens. The responders were retested after 1 or 6 months. Fifty (5/10) and 9.7% (3/31) of JCA patients with and without uveitis, respectively, responded (stimulation index >3) to S-antigen or one of its peptide listed above or yeast histone H3 peptide or R16 of IRBP. None of the healthy controls responded to any of these antigens. The difference in the frequency of responders (SI>3) between JCA associated with uveitis and healthy controls was statistically significant (p=0.001). Similarly, the difference between JCA with and without uveitis was also significant (p=0.013). Our findings suggest that these antigens may have a role in the pathogenesis of uveitis in a subset of patients with JCA.  相似文献   
48.
Anaplastic large cell lymphoma of T/null-cell type (ALCL) is associated with a characteristic genetic abnormality t(2;5) that results in the NPM-ALK chimeric gene and the protein product derived thereof. In 10% to 20% of ALCLs, the translocation partners of the ALK gene are genes other than NPM (variant translocations). ALK gene expression limited to the cytoplasm implies a variant translocation. In this study, we have investigated 46 cases of ALCL for expression and localization of ALK protein and its association with Epstein-Barr virus (EBV) (by hybridization to EBV-encoded nuclear RNA-1 [EBER-1] and immunostaining for LMP-1). ALCL patients with a null cell phenotype were significantly younger as compared with those of T-cell phenotype (mean age: 28 years v 42 years; P =.018). Sixteen of 46 ALCL cases (34%) were ALK positive. ALK-positive patients were significantly younger (mean age: 25 years for those with both cytoplasmic and nuclear staining; 22 years for those with exclusive cytoplasmic staining; and 41 years for those negative for the ALK gene; P =.023). EBER-1 was detected in 9 of 46 cases (20%), and LMP-1 expression was noted in 5 of them. By polymerase chain reaction analysis, all EBV-associated cases that were investigated showed type I EBV. Whereas 2 of 23 T-cell ALCLs (9%) were EBER-1+, and 7 of 23 null-cell ALCLs (30%) showed EBV association (P =.057). EBV association was seen in 20% of ALK-negative cases, in 0% of cases with ALK gene expression in both nucleus and cytoplasm, and in 60% of cases with ALK gene expression exclusively in the cytoplasm (P =.02). Further, although ALK-positive-EBER-1+ cases were LMP-1 negative, ALK-negative-EBER-1+ cases were LMP-1 positive. Our study raises the question whether EBV might have an etiological role in the evolution of ALCLs that lack classical t(2;5).  相似文献   
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Benign and malignant soft tissue tumors of the paratesticular region i.e. those arising from the testicular tunics, epididymis and spermatic cord are uncommon. Of these, leiomyosarcoma arising from the tunica vaginalis is extremely rare. On extensive computerised search, a single case has been reported till date in the literature. We hereby report one such case because of its rarity.  相似文献   
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