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61.
The Italian hare (Lepus corsicanus) is an endangered species whose natural populations have decreased in recent years. This study’s objective was to identify ticks infesting hares and their habitats in a wildlife reserve in southern Italy. In June 2009, ticks were collected by dragging in three transects set in a meadow habitat within an enclosure inhabited by hares and in three similar transects outside this enclosure. Fifty-five ticks were collected by dragging, being 54 inside and 1 outside the enclosure. Ticks were identified as Hyalomma marginatum (34 males, 17 females), Dermacentor marginatus (2 males, 1 female), and Rhipicephalus bursa (1 female). In September 2009, ticks were collected from 17 Italian hares and identified as Ixodes ricinus (2 larvae, 45 nymphs, 35 males, 37 females), Rhipicephalus turanicus (2 males, 1 nymph), and Hyalomma sp. (165 nymphs). PCR amplification and sequencing of a partial region of the 12S rDNA gene of Hyalomma nymphs allowed their identification as H. marginatum. This study suggests that host presence is a factor determining the level of environmental tick infestation as well as the free-living tick species in the study area and that Italian hares are hosts for I. ricinus and H. marginatum. Studies to assess whether these ticks could limit the survival and fitness of Italian hares and affect their conservation status are needed. Moreover, it is necessary to investigate whether these ticks are infected with pathogens of medical and veterinary concern.  相似文献   
62.
Angiotensin converting enzyme (ACE) inhibitors provide well known cardiorenal-protective benefits added to antihypertensive effects in chronic renal disease. These agents are underused in management of patients receiving hemodialysis (HD) because of common concern of hyperkalemia. However, few studies have investigated effect of renin angiotensin aldosterone system (RAAS) blockade on serum potassium in hemodialysis patients. We assessed the safety of ramipril in patients on maintenance HD. We enrolled 28 adult end stage renal disease (ESRD) patients treated by maintenance HD and prescribed them ramipril in doses of 1.25 to 5 mg per day. They underwent serum potassium concentration measurements before ramipril introduction and in 1 to 3 months afterwards. No significant increase in kalemia was found. Results of our study encourage the use of ACE inhibitors in chronically hemodialyzed patients, but close potassium monitoring is mandatory.  相似文献   
63.
Control of T(H)17/T(reg) balance by hypoxia-inducible factor 1   总被引:1,自引:0,他引:1  
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The aim of this investigation was to determine the seroprevalence of H. pylori in patients with coronary artery disease (CAD). Patients with coronary artery disease (n = 90) and control group (n = 90) were enrolled into this randomized, multi-centre study. CAD risk factors analyzed included age, male gender, diabetes mellitus, systemic hypertension, cigarette smoking, hypercholesterolemia and socioeconomic status. The results of this study showed a higher seroprevalence of Helicobacter pylori infection in patients with CAD compared to controls (78.8% versus 58.3%, p < 0.05). However, Helicobacter pylori seropositivity was not associated with coronary artery risk factors (smoking, body mass index, diabetes mellitus, hypertension, total cholesterol and socioeconomic status) either in the whole study population or in the patients and control subjects analyzed separately (P > 0.05). Further study are needed to clarify the precise role of Helicobacter pylori infection on the development of coronary artery disease.  相似文献   
66.
Whereas interleukin-10 (IL-10) is an anti-inflammatory cytokine known to regulate macrophage activation, its full mechanism of action remains incompletely defined. In a screen to identify novel IL-10-induced genes, we cloned the mouse ortholog of human ABIN-3 (also termed LIND). ABIN-3 expression was induced selectively by IL-10 in both mouse and human mononuclear phagocytes coordinately undergoing proinflammatory responses. In contrast to the previously characterized ABINs, mouse ABIN-3 was incapable of inhibiting NF-kappaB activation by proinflammatory stimuli. Generation and analysis of ABIN-3-null mice demonstrated that ABIN-3 is unnecessary for the anti-inflammatory effects of IL-10 as well as for proper negative regulation of NF-kappaB. Conversely, human ABIN-3 was capable of inhibiting NF-kappaB activation in response to signaling from Toll-like receptor, IL-1, and tumor necrosis factor. Enforced expression of human ABIN-3 in human monocytic cells suppressed the cytoplasmic degradation of IkappaBalpha, the activation of NF-kappaB, and the induction of proinflammatory genes. Comparative sequence analyses revealed that mouse ABIN-3 lacks a complete ABIN homology domain, which was required for the functional activity of human ABIN-3. ABIN-3 is, thus, an IL-10-induced gene product capable of attenuating NF-kappaB in human macrophages yet is inoperative in mice and represents a basis for species-specific differences in IL-10 actions.  相似文献   
67.
Neurons integrate and encode complex synaptic inputs into action potential outputs through a process termed "intrinsic excitability." Here, we report the essential contribution of fibroblast growth factor homologous factors (FHFs), a family of voltage-gated sodium channel binding proteins, to this process. Fhf1-/-Fhf4-/- mice suffer from severe ataxia and other neurological deficits. In mouse cerebellar slice recordings, WT granule neurons can be induced to fire action potentials repetitively (approximately 60 Hz), whereas Fhf1-/-Fhf4-/- neurons often fire only once and at an elevated voltage spike threshold. Sodium channels in Fhf1-/-Fhf4-/- granule neurons inactivate at more negative membrane potential, inactivate more rapidly, and are slower to recover from the inactivated state. Altered sodium channel physiology is sufficient to explain excitation deficits, as tested in a granule cell computer model. These findings offer a physiological mechanism underlying human spinocerebellar ataxia induced by Fhf4 mutation and suggest a broad role for FHFs in the control of excitability throughout the CNS.  相似文献   
68.
Vanishing white matter (VWM) is a recessive neurodegenerative disease caused by mutations in translation initiation factor eIF2B and leading to progressive brain myelin deterioration, secondary axonal damage, and death in early adolescence. Eif2b5R132H/R132H mice exhibit delayed developmental myelination, mild early neurodegeneration and a robust remyelination defect in response to cuprizone‐induced demyelination. In the current study we used Eif2b5R132H/R132H mice for mass‐spectrometry analyses, to follow the changes in brain protein abundance in normal‐ versus cuprizone‐diet fed mice during the remyelination recovery phase. Analysis of proteome profiles suggested that dysregulation of mitochondrial functions, altered proteasomal activity and impaired balance between protein synthesis and degradation play a role in VWM pathology. Consistent with these findings, we detected elevated levels of reactive oxygen species in mutant‐derived primary fibroblasts and reduced 20S proteasome activity in mutant brain homogenates. These observations highlight the importance of tight translational control to precise coordination of processes involved in myelin formation and regeneration and point at cellular functions that may contribute to VWM pathology.

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Background

Detection of molecular tumor heterogeneity has become of paramount importance with the advent of targeted therapies. Analysis for detection should be comprehensive, timely and based on routinely available tumor samples.

Aim

To evaluate the diagnostic potential of targeted multigene next-generation sequencing (TM-NGS) in characterizing gastrointestinal cancer molecular heterogeneity.

Methods

35 gastrointestinal tract tumors, five of each intestinal type gastric carcinomas, pancreatic ductal adenocarcinomas, pancreatic intraductal papillary mucinous neoplasms, ampulla of Vater carcinomas, hepatocellular carcinomas, cholangiocarcinomas, pancreatic solid pseudopapillary tumors were assessed for mutations in 46 cancer-associated genes, using Ion Torrent semiconductor-based TM-NGS. One ampulla of Vater carcinoma cell line and one hepatic carcinosarcoma served to assess assay sensitivity. TP53, PIK3CA, KRAS, and BRAF mutations were validated by conventional Sanger sequencing.

Results

TM-NGS yielded overlapping results on matched fresh-frozen and formalin-fixed paraffin-embedded (FFPE) tissues, with a mutation detection limit of 1% for fresh-frozen high molecular weight DNA and 2% for FFPE partially degraded DNA. At least one somatic mutation was observed in all tumors tested; multiple alterations were detected in 20/35 (57%) tumors. Seven cancers displayed significant differences in allelic frequencies for distinct mutations, indicating the presence of intratumor molecular heterogeneity; this was confirmed on selected samples by immunohistochemistry of p53 and Smad4, showing concordance with mutational analysis.

Conclusions

TM-NGS is able to detect and quantitate multiple gene alterations from limited amounts of DNA, moving one step closer to a next-generation histopathologic diagnosis that integrates morphologic, immunophenotypic, and multigene mutational analysis on routinely processed tissues, essential for personalized cancer therapy.  相似文献   
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