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PURPOSE: To evaluate treatment response to intravenous (IV) infliximab (IFX) as a first-line therapy in patients hospitalized for severe Crohn's disease and compare it with our earlier data using IV hydrocortisone. METHODS: Seventeen cases received IFX (5 mg/kg) and were matched for the same goal of therapy to those who had received hydrocortisone (300 mg/d). The Crohn's and Colitis Foundation of America-International Organization of Inflammatory Bowel Disease (CCFA-IOIBD) score was obtained for the IFX-treated cases on admission and daily and the Crohn's disease activity index (CDAI) score weekly throughout the hospitalization and compared with those who received hydrocortisone. Discharge was guided by the same criteria in both groups. RESULTS: For the IFX group, the admission mean CCFA-IOIBD score was 13.5 (+/-4.4). Eight of 17 patients achieved a clinical response with a mean score of 4 (+/-1.5), representing a >or=50% reduction from baseline to discharge. The mean admission score for the hydrocortisone group was 17.75 (+/-7.1) with 13 of 16 achieving a mean score of 4.5 (+/-2.3). The mean discharge score for the 17 IFX patients was 6.9 (+/-3) and for the hydrocortisone group was 5.9 (+/-3.2). Median length of hospitalization for the IFX patients was 4 days (range 1 to 9) and 7.5 (5 to 15) days for the hydrocortisone group (P<0.001). CONCLUSIONS: IFX therapy was an effective first-line agent in patients with severe Crohn's disease who require hospitalization and therefore a primary treatment option. Most patients receiving IFX can anticipate a briefer hospitalization than with IV hydrocortisone. Failure of an early response can provide an opportunity to consider an alternate form of therapy sooner with IFX than with hydrocortisone.  相似文献   
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Optical imaging of individual vesicle exocytosis is providing new insights into the mechanism and regulation of secretion by cells. To study calcium-triggered secretion from astrocytes, we used acridine orange (AO) to label vesicles. Although AO is often used for imaging exocytosis, we found that imaging vesicles labeled with AO can result in their photolysis. Here, we define experimental and analytical approaches that permit us to distinguish unambiguously between fusion, leakage, and lysis of individual vesicles. We have used this approach to demonstrate that lysosomes undergo calcium-triggered exocytosis in astrocytes.  相似文献   
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BACKGROUND: Dexamethasone (DEX) is demonstrated to have anti-inflammatory properties and known to induce hemodynamic improvement in sepsis and septic shock. L-arginine (L-arg), a semi-essential amino acid, depending on its metabolic pathway, becomes very essential in stress situations such as heatstroke, burns, sepsis, trauma, and wound healing. The aim of this study was to evaluate the synergistic therapeutic effect of DEX and L-arg in rescuing the mice from experimental septic shock induced by bacterial lipopolysaccharide (LPS). The experiments were designed to delineate the molecular mechanisms responsible for the increased therapeutic benefit of the combination therapy (CT) in LPS-induced septic shock. METHODS: Acute endotoxemia was induced in Swiss male mice by i.p. injection of LPS (18 mg kg(-1)) at 0 h. LPS-treated mice were divided into four groups. The first group (DEX group) received DEX (2 mg kg(-1)) i.p. at +2 h of LPS. The second group (L-arg group) received L-arg i.p. at a dose of 120 mg/kg at +6 h of LPS injection. The third group (CT group) received DEX (2 mg kg(-1)) at +2 h LPS followed by L-arg at +6 h of LPS injection. The fourth group received saline in place of L-arg or DEX (LPS group). A sham group was also included, where normal mice received saline in place of LPS or L-arg or DEX. At +6 h, mice from sham group, LPS group, and DEX group were sacrificed at +24 h. Mice from sham group, DEX group, L-arg group, and CT group were sacrificed to examine various parameters associated with LPS endotoxemia. RESULTS: The CT with DEX followed by L-arg significantly increased the survival of mice injected with a lethal dose of LPS. Monotherapy with either DEX or L-arg given at the same dose and time did not increase the survival of the mice injected with LPS. DEX administration could significantly reduce the levels of serum TNF-alpha, IL-1beta, IFN-gamma, aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT), and nitrite. DEX also down-regulated the expression of liver-inducible nitric oxide synthase (iNOS), and up-regulated the levels of serum anti-inflammatory cytokines like TGF-beta1 and IL-4, hepatic and splenic arginase, in LPS-injected mice. The enhanced therapeutic effect of CT correlated with reduced pathological symptoms, decreased Th1 cytokines, increased TGF-beta1 and arginase levels compared to the mice administered with either of the monotherapies. The CT group had significantly increased expression of hepatic Hsp 70 and reduced septic shock associated histopathology, in lung and liver, compared to the mice treated with either DEX or L-arg. CONCLUSIONS: The therapeutic combination therapy with DEX and L-arg, at the appropriate dose, time, and sequence of administration, changed the cytokine profile, in favor of reducing the inflammatory response. The significantly enhanced survival observed in the CT group was accompanied by an increased hepatic Hsp 70, hepatic arginase, splenic arginase, and decreased organ injury. This novel concept of combined therapy could form the basis of an effective therapeutic approach in the treatment of sepsis and septic shock.  相似文献   
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An economical and facile synthesis of alpha,alpha'-(EE)-bis(benzylidene)-cycloalkanones was achieved by the reaction of cycloalkanones with different aromatic aldehydes using ethanolic KOH in good yields. Few of the selected compounds were reduced with NaBH(4) to the respective alpha,alpha'-(EE)-bis(benzylidene)-cycloalkanols. All these compounds and our earlier synthesized cyclohexyl phenyl methanols were evaluated for their antitubercular, antifungal and antibacterial activities. Several compounds displayed moderate antitubercular activity with MIC=12.5-1.56 microg/mL. However, none of the compounds displayed any significant antifungal activity.  相似文献   
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Mohanty SK  Balani JP  Parwani AV 《Urology》2007,70(4):812.e7-812.10
Teratomas with malignant transformation occur in approximately 3 to 6% of patients with metastatic germ cell tumors treated with platinum-based chemotherapy. The histology of the nongerm cell (somatic) malignant elements most commonly includes carcinoma and various types of sarcomas; however, so far as the primitive neuroectodermal tumors (PNETs) are concerned the experience is quite limited. There are only seven documented case reports and occasional series of PNET in association with testicular teratoma either in the primary site or in the metastatic location. We report a relatively unusual case of PNET arising in a malignant mixed germ cell tumor in a 35-year-old man.  相似文献   
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