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971.
Hepatic encephalopathy (HE) is a complex neuropsychiatric syndrome that typically develops as a result of acute liver failure or chronic liver disease. Brain edema is a common feature associated with HE. In acute liver failure, brain edema contributes to an increase in intracranial pressure, which can fatally lead to brain stem herniation. In chronic liver disease, intracranial hypertension is rarely observed, even though brain edema may be present. This discrepancy in the development of intracranial hypertension in acute liver failure versus chronic liver disease suggests that brain edema plays a different role in relation to the onset of HE. Furthermore, the pathophysiological mechanisms involved in the development of brain edema in acute liver failure and chronic liver disease are dissimilar. This review explores the types of brain edema, the cells, and pathogenic factors involved in its development, while emphasizing the differences in acute liver failure versus chronic liver disease. The implications of brain edema developing as a neuropathological consequence of HE, or as a cause of HE, are also discussed. 相似文献
972.
为了探讨卵巢癌细胞与巨噬细胞共培养后对B7.H1表达的影响及其可能机制,利用佛波酯(PMA)诱导THP-1或外周血单核细胞分化为巨噬细胞后,与人卵巢癌细胞株SKOV3体外非接触共培乔24h,qRT-PCR、Western blot以及流式细胞术分别检测SKOV3与巨噬细胞B7-H1的表达:进一步利用NF-KB、JAK2/STAT3、p38MAPK信号通路的抑制剂作用于共培养体系,检测B7-H1表达的变化,以探讨其机制。结果显示,共培养24h后,SKOV37L巨噬细胞B7-H1mRNA和蛋白的表达较非共培养组均显著升高(P〈0.05),而阻断NF-κB、JAK2/STAT3、p38MAPK信号通路后,B7-H1的上调均明显被抑制(P〈0.05)。SKOV3与巨噬细胞共培养后B7-H1的表达升高伊〈0.05),其机制可能涉及到NF—κB、JAK2/STAT3、p38MAPK信号通路的激活。 相似文献
973.
Qing-He Zhang Hong-Min Sun Rui-Zhi Zheng Ying-Chun Li Qian Zhang Pan Cheng Zhen-Hai Tang Fen Huang 《Gene》2013
MicroRNA-183 (miR-183) family is proposed as promising biomarkers for early cancer detection and accurate prognosis as well as targets for more efficient treatment. The results of their expression feature in cancer tissues are inconsistent and controversy still exists in identifying them as new biomarkers of cancers. Therefore, to systemically evaluate the most frequently reported cancers in which miR-183 family members were up- or down-regulated is critical for further investigation on physiological impact of its aberrant regulation in specific cancers. The published studies that compared the level of miR-183 family expression in cancer tissues with those in noncancerous tissues were reviewed by the meta-analysis with a vote-counting strategy. Among the 49 included studies, a total of 18 cancers were reported, with 11 cancers reported in at least two studies. In the panel of miR-183 family members' expression analysis, colorectal cancer and prostate cancer ranked at the top among consistently reported cancer types with up-regulated feature. Bladder cancer, lung cancer and hepatocellular carcinoma were the third most frequently reported cancer types with significant over-expression of miR-96, miR-182 and miR-183 respectively. Breast cancer and gastric cancer were presented with inconsistent regulations and the members of this family had their own distinct regulated features in other different cancers. MiR-183 family, either individually or as a cluster, may be useful prognostic markers and/or therapeutic targets in several cancers. Further studies and repeat efforts are still required to determine the role of miR-183 family in various cancer progressions. 相似文献
974.
Armando Grossi Alessia Palma Ginevra Zanni Antonio Novelli Sara Loddo Marco Cappa Alessandra Fierabracci 《Gene》2013
Turner syndrome is a condition caused by numeric and structural abnormalities of the X chromosome, and is characterized by a series of clinical features, the most common being short stature and gonadal dysgenesis. An increased frequency of autoimmune diseases as well as an elevated incidence of autoantibodies has been observed in Turner patients. 相似文献
975.
Laia Rodriguez-Revenga Irene Madrigal Josep Blanch-Rubió Dei M. Elurbe Elisa Docampo Antonio Collado Javier Vidal Jordi Carbonell Xavier Estivill Montserrat Mila 《Gene》2013
Fibromyalgia is a chronic condition characterized by widespread pain, fatigue, non-restorative sleep and cognitive difficulties that affects 2–4% of the general population. Recently a possible relationship between the FMR1 premutation and fibromyalgia has been pointed out. In attempt to gather more data we screened for the FMR1 CGG expansion 700 DNA samples from unrelated fibromyalgia patients. This data might be useful for evaluating the incorporation of this test in rheumatologic procedures for women with fibromyalgia. The observed frequency of FMR1 premutation carriers (3 of 700, 0.4%) is not significantly different from the estimated rate in the general female population (1/250–1/400) (P = 0.539, P = 0.716). Clinical examination of the FMR1 premutation carriers identified revealed that all of them had important neurological symptoms with regard to muscular symptoms, neurocognitive alterations and neurovegetative impairments. With regard to other clinical aspects of the disease the cases apparently did not differ from the average fibromyalgia patients. On the basis of our results an FMR1 screening among fibromyalgia female patients would not be recommended. However it would be worthwhile to further evaluate the different clinical presentations that fibromyalgia patients might present based on their FMR1 premutation carrier status. 相似文献
976.
Abstract The lugworm, Arenicola marina L. has an annual cycle of reproduction with epidemic spawning and external fertilisation. The spermatozoa of Arenicola are unusual in that they are held immotile (as plates of several hundred cells known as morulae) in the coelomic fluid until activated just prior to spawning. Activation of Arenicola sperm is brought about by a sperm maturation factor (SMF) from the prostomium and can be carried out in vitro using an assay technique developed by Bentley (1985). Scanning electron microscopy is used here to examine the changes which occur during in vitro activation. This revealed that the bundles of flagella of inactive sperm become disorganised as flagella beating commences but the flagella at this stage are still bound together at their tips. The sperm heads then become separated from the cytophore and finally the distal binding of the flagella is broken to give free-swimming spermatozoa. Coelomocytes present in the coelomic fluid resorb unspawned gametes prior to the initiation of the next gametogenic phase. 相似文献
977.
《Chronobiology international》2013,30(5):420-431
In 33 patients with heart failure (NYHA 11-III), the 24-h blood pressure rhythm was examined before and after the titration period of two ACE inhibitors. Blood pressure was measured by the oscillometric method using the blood pressure monitor 90202 from SpaceLabs, Inc. The measurements were taken from 06:OO to 22:OO h every 20 min and from 22:00 to 06:00 h every hour. Patients were randomized to therapy with either captopril (group 1, n = 17) or enalapril (group 2, n = 16). The average daily dosage of captopril was 41 ± 3 mg given in three divided doses (08:00, 12:00, and 17:00 h). The mean dose of enalapril was 8 ± 1 mg once daily (08:00 h). Serum electrolytes, serum creatinine, and plasma renin activity were measured before and during therapy with both ACE inhibitors. Twenty-four-hour blood pressure measurements were taken before and on the fifth day of treatment with ACE inhibitors. Both groups were not different with respect to the degree of heart failure, the concomitant medication, and the 24-h profiles of blood pressure and heart rate before initiation of ACE inhibition. The 24-h blood pressure values on day 5 were consistently below the pretreatment values (p < 0.005) in both groups. Both groups did not differ significantly during ACE inhibition in their 24-h blood pressure and heart rate profiles. In both groups, the mesor of the systolic and diastolic blood pressure decreased significantly by the same degree (by 4.7/5.1 mmg Hg in group 1 and 6.4/4.1 mm Hg in group 2). The systolic/diastolic blood pressure amplitude decreased slightly in both groups. Before treatment, serum sodium, potassium, and creatinine were within the normal range. The increase in potassium (0.5 ± 0.1 mmol/L) reached statistical significance (p < 0.01) only in the captopril group, whereas it was not significant in the enalapril group (0.1 ± 0.1 mmol/L). Serum creatinine was not significantly altered by both ACE inhibitors. No relationship could be found between the changes in serum potassium or creatinine and the mean of the 24-h blood pressure values during ACE inhibition. Captopril and enalapril showed comparable blood pressure profiles and similar effects on renal function at the end of the titration on day 5. It can therefore be concluded that the effects on blood pressure rhythm and renal function are similar with a single daily dose of enalapril compared to captopril given three times daily. 相似文献
978.
《Chronobiology international》2013,30(6):1206-1221
Hypertension can cause or promote renal failure and is related to cardiovascular mortality, the major cause of death in patients with renal impairment. Changes in the circadian BP pattern, particularly the blunting or reversal of the nocturnal decline in BP, are common in chronic renal failure. These changes in turn are among the major determinants of left ventricular hypertrophy. Using a chronobiological approach, it is possible to obtain better insight into the reciprocal relationship between hypertension, renal disease, and increased cardiovascular risk of renal patients. Disruption of the normal circadian rhythm of rest/activity may be hypothesized to underlie the high cardiovascular morbidity and mortality of such patients. Epidemiological studies reveal that hemodialysis patients experience poor subjective sleep quality and insomnia and, in comparison to healthy persons, are more likely to show shorter sleep duration and lower sleep efficiency. Sleep apnea may be present and is usually investigated in these patients; however, the prevalence of restless legs syndrome (RLS), which is high in dialysis patients and which has been associated with increased risk for cardiovascular disease in the general population, could also play a role in the pathogenesis of sleep-time hypertension in renal patients. Careful assessment of sleep quality, in particular, diagnostic screening for RLS and periodic limb movements (PLM) in renal patients, is highly recommended. In renal failure, attention to sleep quality and related perturbations of the sleep/wake cycle may help prevent the occurrence and progression of cardiovascular disease. (Author correspondence: prf@unife. it) 相似文献
979.
Jee HJ Kim HJ Kim AJ Song N Kim M Yun J 《Biochemical and biophysical research communications》2011,408(4):669-673
Cellular senescence plays an important role in tumor suppression. The mitotic kinase Nek6 has recently been shown to be overexpressed in various cancers and has been implicated in tumorigenesis. Previously, we reported that the down-regulation of Nek6 expression was required for p53-induced senescence. In this study, we examined the effect of Nek6 overexpression on the premature senescence of cancer cells induced by the anticancer drugs camptothecin (CPT) and doxorubicin (DOX). We found that CPT- and DOX-induced morphology changes and increases in senescence-associated β-galactosidase staining were significantly inhibited in EJ human bladder cancer cells and H1299 human lung cancer cells overexpressing HA-Nek6. DOX-induced G2/M cell cycle arrest and the reduction in cyclin B and cdc2 levels after DOX treatment were significantly reduced by Nek6 overexpression. In addition, an increase in the intracellular levels of ROS in response to DOX was also inhibited in cells overexpressing Nek6. These results suggest that the increased expression of Nek6 renders cancer cells resistant to premature senescence, and targeting Nek6 could be an efficient strategy for cancer treatment. 相似文献
980.
Tomokuni A Eguchi H Tomimaru Y Wada H Kawamoto K Kobayashi S Marubashi S Tanemura M Nagano H Mori M Doki Y 《Biochemical and biophysical research communications》2011,(4):675-680
Previous studies have demonstrated expression of Toll-like receptors (TLRs) in the surface epithelium of normal ovaries (OSE) and in epithelial ovarian tumors. Most notably, OSE-derived cancers express TLR4, which activates the nuclear factor-kappa B (NF-κB) signaling cascade as a mediator of inflammatory response. Currently, there is considerable interest in elucidating the role of TLR-mediated signaling in cancers. Nevertheless, the expression of TLRs in granulosa cell tumors (GCTs) of the ovary, and the extent to which GCT expression of TLRs may influence cell-signaling pathways and/or modulate the efficacy of chemotherapeutics, has yet to be determined. In the present study, human GCT lines (COV434 and KGN) were utilized to evaluate expression of functional TLR4. TLR4 is expressed in GCT cell lines and ligation of TLR4 with bacterial lipopolysaccharide (LPS) led to IκB degradation and activation of NF-κB. NF-κB activation was confirmed by nuclear localization of NF-κB p65 following treatment with LPS and the naturally occurring ligand, HSP60. Notably, immunoneutralization of TLR4 blocked nuclear localization, and inhibition of NF-κB signaling attenuated LPS-induced TNFα plus increased doubling time in both cell lines. Contradictory to reports using human OSE cell lines, inhibition of NF-κB signaling failed to sensitize GCT lines to TRAIL or cisplatin. In summary, findings herein are the first to demonstrate a functional TLR-signaling pathway specifically in GCTs, and indicate that in contrast to OSE-derived cancers, inhibition of NF-κB does not sensitize GCTs to TRAIL or cisplatin. 相似文献