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91.
Introduction: The aim of this study was to evaluate the concentration of interleukin-6 and N-terminal propeptide of procollagen type I and their relationship in liver diseases of different etiologies.

Material and methods: Serum samples were obtained from 30 healthy volunteers and patients suffering from alcoholic cirrhosis (AC) – 31, non-alcoholic cirrhosis (NAC) – 28 and toxic hepatitis (HT) – 23 patients. Cirrhotic patients were classified according to Child–Pugh score. IL-6 and PINP concentrations were determined according to the electrochemiluminescence immunoassay.

Results: The mean serum IL-6 concentration was significantly higher in AC (mean?±?SD:21.52?± 15.01?pg/mL), NAC (20.07?±?32.12?pg/mL) and HT (15.14?±?17.18?pg/mL) when compared to the control group (C) (1.67?±?0.42?pg/mL) (Mann–Whitney U test: p?p?p?=?.020 and p?p?p?=?.022, respectively). IL-6 and PINP concentrations appeared to vary depending on the severity of liver damage (p?p?p?Conclusions: We conclude that serum concentrations of IL-6 and PINP change in liver diseases, and those changes reflect the severity of liver disease.  相似文献   
92.
93.
BACKGROUND/AIMS: Thrombocytopenia often accompanies chronic liver diseases. It can occur due to the decrease in blood platelet production by megakaryocytes, the increase in peripheral destruction, or splenic sequestration. METHODOLOGY: We estimate the reticulated platelets by use of flow cytometry in patients with liver cirrhosis with thrombocytopenia (n-24, platelets median (M)-77g/L), with normal platelet count (n-16, platelets M-193g/L) and in healthy (n-27, platelets M-242g/L). The level of reticulated platelets was determined in whole peripheral blood stained with thiazole orange and incubated with monoclonal antibodies anti-CD41. RESULTS: Patients with liver cirrhosis and thrombocytopenia revealed significantly lower reticulated platelet levels than patients without thrombocytopenia and healthy subjects (M-1.0% vs. 1.5% vs. 2.0% respectively). The correlation between reticulated platelet level and platelet count, serum level of thrombopoietin and hepatocyte growth factor in liver cirrhosis was not established. An inverse correlation was noted between reticulated platelets and thrombopoietin (r - 0.6, p<0.01) and hepatocyte growth factor (r - 0.5, p<0.01) in the control group. A positive correlation between platelet count in liver cirrhosis and serum level of thrombopoietin (r - 0.35, p<0.05) and hepatocyte growth factor (r - 0.48, p<0.01) was observed. CONCLUSIONS: Our studies showed that decreased production of platelets by megakaryocytes due to low thrombopoietin concentration could be a possible cause of thrombocytopenia in liver cirrhosis.  相似文献   
94.
The maintenance of photoreceptor cell polarity is compromised by the rhodopsin mutations causing the human disease autosomal dominant retinitis pigmentosa. The severe form mutations occur in the C-terminal sorting signal of rhodopsin, VXPX-COOH. Here, we report that this sorting motif binds specifically to the small GTPase ARF4, a member of the ARF family of membrane budding and protein sorting regulators. The effects of blocking ARF4 action were functionally equivalent to the effects of blocking the rhodopsin C-terminal sorting signal. ARF4 was essential for the generation of post-Golgi carriers targeted to the rod outer segments of retinal photoreceptors. Thus, the severe retinitis pigmentosa alleles that affect the rhodopsin sorting signal interfere with interactions between ARF4 and rhodopsin, leading to aberrant trafficking and initiation of retinal degeneration.  相似文献   
95.
ABT-263 is a potent, orally bioavailable inhibitor of the antiapoptotic Bcl-2 family members Bcl-2, Bcl-x(L), and Bcl-w, which is currently in phase I clinical trials. Previous work has shown that this compound has low nanomolar cell-killing activity in a variety of lymphoma and leukemia cell lines, many of which overexpress Bcl-2 through a variety of mechanisms. Rapamycin is a macrolide antibiotic that inhibits the mammalian target of rapamycin complex, leading to cell cycle arrest and inhibition of protein translation. Rapamycin (and its analogues) has shown activity in a variety of tumor cell lines primarily through induction of cell cycle arrest. Activity has also been shown clinically in mantle cell lymphoma and advanced renal cell carcinoma. Here, we show that treatment of the follicular lymphoma lines DoHH-2 and SuDHL-4 with 100 nmol/L rapamycin induces substantial G(0)-G(1) arrest. Addition of as little as 39 nmol/L ABT-263 to the rapamycin regimen induced a 3-fold increase in sub-G(0) cells. Combination of these agents also led to a significant increase in Annexin V staining over ABT-263 alone. In xenograft models of these tumors, rapamycin induced a largely cytostatic response in the DoHH-2 and SuDHL-4 models. Coadministration with ABT-263 induced significant tumor regression, with DoHH-2 and SuDHL-4 tumors showing 100% overall response rates. Apoptosis in these tumors was significantly enhanced by combination therapy as measured by staining with an antibody specific for cleaved caspase-3. These data suggest that combination of ABT-263 and rapamycin or its analogues represents a promising therapeutic strategy for the treatment of lymphoma.  相似文献   
96.
Bacterial flagellin can interact with both Toll-like receptor 5 (TLR5) and the cell surface glycolipid, asialoGM1, to activate an innate immune response. The induction of mucin by flagellin in human lung epithelial cells (NCIH292) is dependent on asialoGM1 ligation, ATP receptor signaling, Ca2+ mobilization, and Erk1/2 activation. Conversely, the activation of NF-kappaB by flagellin is dependent on signaling through TLR5. These results prompted us to ask whether the flagellin-induced TLR5 signaling pathway was intersecting with or mutually independent of the nucleotide receptor pathway activated downstream of asialoGM1. Herein, we demonstrate that the release of ATP induced by flagellin is dependent on a Toll signaling cascade. Although Toll was able to activate NF-kappaB in the absence of extracellular ATP, Toll required ATP to activate Erk1/2. These results suggest interdependence between the asialoGM1 and TLR5 pathways and reveal a previously unsuspected role for autocrine extracellular ATP signaling in TLR signaling.  相似文献   
97.
Expression of β2-integrin on leukocytes in liver cirrhosis   总被引:2,自引:0,他引:2  
AIM: To analyze beta2-integrin expression on blood leukocytes in liver cirrhosis. METHODS: In 40 patients with liver cirrhosis and 20 healthy individuals, the evaluation of expression of CD11a (LFA-1alpha), CD11b (Mac-1alpha), CD11c (alphaX) and CD49d (VLA-4alpha) on peripheral blood leukocytes was performed using flow cytometry. The analysis was carried out in groups of patients divided into B and C according to Child-Pugh's classification. RESULTS: An increased CD11a, CD11b, CD11c and CD49d integrin expression was observed on peripheral blood leukocytes in liver cirrhosis. The integrin levels were elevated as the advancement of liver failure progressed. The highest expression of integrins occurred predominantly on monocytes. A slight expression of VLA-4 was found on lymphocytes and granulocytes and it increased together with liver failure. A positive correlation was noted between median intensity of fluorescence (MIF) expression on polymorphonuclear cells of CD11a and CD11c and CD49d (r = 0.42, P < 0.01; r = 053, P < 0.01, respectively) in liver cirrhosis stage C. However, no correlation was observed between integrin expression on leukocytes. The concentrations of sICAM-1, sVCAM-1, and TNFalpha, were significantly elevated in liver cirrhosis. CONCLUSION: beta2-integrin expression on leukocytes increases in liver cirrhosis decompensated as the stage of liver failure increases, which is a result of permanent activation of leukocytes circulating through the inflamed liver environment. beta2-integrin expression on circulating leukocytes can intensify liver cirrhosis.  相似文献   
98.
Ripples are 100-200 Hz short-duration oscillatory field potentials that have recently been recorded in rat hippocampus and entorhinal cortex. They reflect fast IPSPs on the soma of pyramidal cells, which occur during synchronous afferent excitation of principal cells and interneuron networks. We now describe two similar types of high-frequency field oscillations recorded from the entorhinal cortex and hippocampus of patients with mesial temporal lobe epilepsy. The first type appears be the human equivalent of normal ripples in the rat. The second, which we have termed fast ripples (FR), are in the frequency range of 250-500 Hz. FR are found in the epileptogenic region and may reflect pathological hypersynchronous population spikes of bursting pyramidal cells.  相似文献   
99.
The purpose of this study was to evaluate the efficacy of an integrative treatment approach on cognitive performance. The study sample comprised 35 medically ill patients (20 male, 15 female) with an average age of 71.05, who were diagnosed with mild dementia and depression. These patients were evaluated at baseline and at six, 12, and 24 months of treatment, which included antidepressants (sertraline, citalopram, or venlafaxine XR, alone or in combination with bupropion XR), cholinesterase inhibitors (donepezil, rivastigmine or galantamine), as well as vitamins and supplements (multivitamins, vitamin E, alpha-lipoic acid, omega-3 and coenzyme Q-10). Patients were encouraged to modify their diet and lifestyle and perform mild physical exercises. Results show that the integrative treatment not only protracted cognitive decline for 24 months but even improved cognition, especially memory and frontal lobe functions.  相似文献   
100.
This paper describes the procedure of assembling a miniature microdrive and silicon probe system for surgical implantation into the adult rat brain. Successful recordings of single and multiunit activity with parallel depth profiles of spontaneous and evoked field potentials are shown. The procedure for histological verification of the position of the silicon probe is described.  相似文献   
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