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131.
Background In patients with cirrhosis, subclinical hepatic encephalopathy, which negatively affects the activity of daily living, is often unidentified. In a multicenter observational study, we investigated the possibility of detecting minimal neurological changes consistent with subclinical hepatic encephalopathy by using the Trail Making Test in a cohort of patients with liver cirrhosis at hospital admission. Methods Seventy-seven consecutive patients with liver cirrhosis were studied (mean age, 69.5 ± 9.1; 95% confidence interval, 67.5–71.6 years). In all patients, possible encephalopathy was investigated according to the West Haven criteria. All those free of any sign of encephalopathy (West Haven 0) were also studied by the Trail Making Test forms A and B. The Child-Pugh score was determined in all patients, and results were compared with the West Haven stage. Exclusion criteria were use of benzodiazepine, beta adrenergic blockers, alcohol, or antiepileptic drugs, or coexistence of depression, dementia, Parkinson's disease, or chronic or acute cerebral vasculopathy. Results Of the 77 patients, 44 (57.1%, 23 men and 21 women) had West Haven score 0, but among these, 26 (59.1%) were diagnosed with mental impairment likely linked to minimal hepatic encephalopathy. Severity of liver disease correlated with the presence of likely minimal hepatic encephalopathy, because the prevalence of abnormal Trail Making Test results increased from 22.2% in Child-Pugh A, to 63.4% and 74.0% in Child-Pugh B and C, respectively. Conclusions The investigation of patients with cirrhosis by the West Haven test is not sufficient to identify subclinical forms of encephalopathy. The Trail Making Test (a simple, inexpensive test) in our series evidenced poor psychometric performance in more than half of the patients who were free of manifest encephalopathy. Subclinical hepatic encephalopathy was present mostly in patients with HCV-related cirrhosis. Detecting minimal hepatic encephalopathy in patients with cirrhosis may help improve their quality of life.  相似文献   
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With the increasing number of cancer survivors, we can observe a population that will present a higher risk of developing secondary long-term toxicities related to adjuvant chemo and radiotherapy regimens. Among these, children surviving from acute lymphoblastic leukemia (ALL) that were treated with prophylactic cranial irradiation represent a group of patients at a high risk of developing secondary brain tumors. Radiation-induced intracranial tumors have been documented since 1950, and today, more than one-hundred cases have been described. We report our experience with two young patients who were hospitalized for low grade gliomas and had a positive anamnesis for ALL and consequent radiotherapy.  相似文献   
134.
Purpose: We analyzed the effects of seletracetam (ucb 44212; SEL), a new antiepileptic drug candidate, in an in vitro model of epileptic activity. The activity of SEL was compared to the effects of levetiracetam (LEV; Keppra), in the same assays. Methods: Combined electrophysiologic and microfluorometric recordings were performed from layer V pyramidal neurons in rat cortical slices to study the effects of SEL on the paroxysmal depolarization shifts (PDSs), and the simultaneous elevations of intracellular Ca2+ concentration [Ca2+]i. Moreover, the involvement of high‐voltage activated Ca2+ currents (HVACCs) was investigated by means of patch‐clamp recordings from acutely dissociated pyramidal neurons. Results: SEL significantly reduced both the duration of PDSs (IC50 = 241.0 ± 21.7 nm ) as well as the number of action potentials per PDS (IC50 = 82.7 ± 9.7 nm ). In addition, SEL largely decreased the [Ca2+]i rise accompanying PDSs (up to 75% of control values, IC50 = 345.0 ± 15.0 nm ). Furthermore, SEL significantly reduced HVACCs in pyramidal neurons. This effect was mimicked by ω‐conotoxin GVIA and, to a lesser extent, by ω‐conotoxin MVIIC, blockers of N‐ and Q‐type HVACC, respectively. The combination of these two toxins occluded the action of SEL, suggesting that N‐type Ca2+ channels, and partly Q‐type subtypes are preferentially targeted. Conclusions: These results demonstrate a powerful inhibitory effect of SEL on epileptiform events in vitro. SEL showed a higher potency than LEV. The effective limitation of [Ca2+]i influx might be relevant for its antiepileptic efficacy and, more broadly, for pathologic processes involving neuronal [Ca2+]i overload.  相似文献   
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OBJECTIVE—Heat shock protein 27 (HSP27) is a member of the small heat shock protein family of proteins. HSP27 expression is enhanced in target tissues of diabetic microvascular complications, and changes in circulating serum HSP27 levels (sHSP27) have been reported in patients with macrovascular disease. We investigated whether sHSP27 levels were associated with micro- and macrovascular complications in type 1 diabetic patients.RESEARCH DESIGN AND METHODS—A cross-sectional, nested, case-control study from the EURODIAB Prospective Complications Study of 531 type 1 diabetic patients was performed. Case subjects (n = 363) were defined as those with one or more complications of diabetes; control subjects (n = 168) were defined as those with no evidence of any complication. We measured sHSP27 levels and investigated their associations with diabetes complications.RESULTS—Mean sHSP27 levels were significantly higher in case subjects with distal symmetrical polyneuropathy (DSP) than in control subjects, even after adjustment for age and albumin excretion rate (AER) (785.9 vs. 574.7 pg/ml, P = 0.03). In logistic regression analysis, sHSP27 levels in the upper quartile were associated with a twofold increased odds ratio (OR) of DSP, independently of conventional risk factors, markers of inflammation, and AER (OR 2.41 [95% CI 1.11–5.24]).CONCLUSIONS—In this large cohort of type 1 diabetic subjects, we found an independent association between sHSP27 and DSP. This suggests that sHSP27 levels may be a novel marker for diabetic neuropathy.Heat shock protein 27 (HSP27), a member of the small heat shock protein family of proteins, is a highly conserved peptide of ∼27 kDa associated with cytoskeletal actin (1). In addition to its chaperone activity, HSP27 acts as a filament stabilizer under stress conditions, interferes with apoptotic pathways, and participates in cytoskeletal dynamics by controlling actin polymerization (2). Therefore, HSP27 plays an important role in both cytoprotection and cell motility.Recent studies in experimental diabetes have shown HSP27 overexpression in glomeruli (3), dorsal root ganglia (4,5), retina (6), and the area adjacent to atherosclerotic plaque (7), indicating HSP27 induction in target tissues of diabetes complications. HSP27 is also released into circulation (8). A pilot study has shown reduced plasma HSP27 levels in patients with carotid stenosis (9), but in a more recent study, HSP27 levels were increased in patients with acute coronary syndromes (7). However, no large study is yet available on circulating HSP27 in vascular disease.Type 1 diabetes is associated with a greatly increased risk of vascular complications that cannot be completely accounted for by conventional risk factors. The aim of the present study was to assess whether high serum HSP27 (sHSP27) levels increased odds ratios (ORs) of micro- and macrovascular complications in a nested case-control sample of type 1 diabetic individuals from the EURODIAB Prospective Complications Study.  相似文献   
137.
The genetic aetiology of familial aggregations of breast cancer and sarcomas has been elucidated only in part. In this study, 23 unrelated individuals from families with one case of sarcoma and at least one case of breast cancer were screened for mutations in the TP53, BRCA1 and BRCA2 genes. Families were classified according to their conformity to the criteria defining the Li-Fraumeni syndrome (LFS), Li-Fraumeni-like (LFL) syndrome and hereditary breast/ovarian cancer (HBOC). Germline TP53 mutations were identified in three instances (13%), including one LFS and two LFL families, while none of the non-LFS/non-LFL families had a TP53 mutation. Three cases (13%), including one with a TP53 mutation, carried BRCA2 mutations. Of these, two were observed in LFL/HBOC families and the other one in a non-LFS/non-LFL/HBOC family, while none of the non-HBOC families tested positive. These findings suggest that the screening of BRCA2, in addition to TP53, may be appropriate for the molecular characterisation of breast cancer/sarcoma families, with practical implications for counselling and clinical management.  相似文献   
138.
LAM, a rare lung disease typically affecting women of reproductive age, is characterized by abnormal proliferation of smooth--muscle cells and progressive loss of pulmonary function due to destruction of lung parenchyma. Two cases of bilateral successive recurrent spontaneous pneumothorax and haemoptysis are presented. Repeated conventional and video-assisted surgery was required in both cases, for drainage of the recurrent pneumothorax and resection of subpleural bulla, with good immediate postoperative evolution. Immunohistochemical studies of resected specimens revealed LAM cells in the lung parenchyma with receptors for oestrogen and progesterone. HMB45 monoclonal antibodies in the LAM cells were identified in one case. The follow-up of the patients revealed no signs of recurrence at 84 and 18 months respectively, although pulmonary transplantation should be considered in case of further deterioration of respiratory function.  相似文献   
139.
Histone deacetylases (HDAC) control gene expression by changing histonic as well as non histonic protein conformation. HDAC inhibitors (HDACi) are considered to be among the most promising drugs for epigenetic treatment for cancer. Recently a strict relationship between histone hyperacetylation in specific tissues of mouse embryos exposed to two HDACi (valproic acid and trichostatin A) and specific axial skeleton malformations has been demonstrated. The aim of this study is to verify if boric acid (BA), that induces in rodents malformations similar to those valproic acid and trichostatin A-related, acts through similar mechanisms: HDAC inhibition and histone hyperacetylation. Pregnant mice were treated intraperitoneally with a teratogenic dose of BA (1000 mg/kg, day 8 of gestation). Western blot analysis and immunostaining were performed with anti hyperacetylated histone 4 (H4) antibody on embryos explanted 1, 3 or 4 h after treatment and revealed H4 hyperacetylation at the level of somites. HDAC enzyme assay was performed on embryonic nuclear extracts. A significant HDAC inhibition activity (compatible with a mixed type partial inhibition mechanism) was evident with BA. Kinetic analyses indicate that BA modifies substrate affinity by a factor alpha=0.51 and maximum velocity by a factor beta=0.70. This work provides the first evidence for HDAC inhibition by BA and suggests such a molecular mechanism for the induction of BA-related malformations.  相似文献   
140.
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