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61.
Several culprits may be identified at postmortem in sudden death (SD) victims, including coronary artery, myocardial, valve, conduction system, and congenital heart diseases. However, particularly in young people, the heart can be found grossly and histologically normal in a not-so-minor amount of cases (the so-called unexplained SD or “mors sine materia”) and inherited ion channel diseases are implicated (long and short QT syndromes, Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia). These channelopathies are due to defective genes encoding for proteins of sodium and potassium ion channels at the sarcolemma level or for receptors regulating intracellular calcium release at the sarcoplasmic reticulum level. Postmortem investigation may still represent the first opportunity to make the proper diagnosis also in the setting of a structurally normal heart and the employment of molecular biology techniques is of help to solve the puzzle of such “silent” autopsies. For these reasons, autopsy investigation of cardiac SD should always include sampling for genetic testing to search for the invisible inherited arrhythmogenic disorders, as recommended in the recent guidelines by the Association for European Cardiovascular Pathology.  相似文献   
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Brain atrophy has consistently been observed in schizophrenia, representing a 'gross' evidence of anatomical abnormalities. Reduced cerebral blood volume (CBV) may accompany brain size decrement in schizophrenia, as suggested by prior small SPECT studies. In this study, we non-invasively investigated the hemisphere CBV in a large sample of patients suffering from schizophrenia with perfusion-weighted imaging (PWI). PWI images were obtained, following intravenous injection of paramagnetic contrast agent (Gadolinium-DTPA), for 54 DSM-IV patients with schizophrenia (mean age+/-SD=39.19+/-12.20 years; 34 males, 20 females) and 24 normal controls (mean age+/-SD=44.63+/-10.43 years; 9 males, 15 females) with a 1.5T Siemens magnet using an echo-planar sequence (TR=2160 ms, TE=47 ms, slice thickness=5mm). The contrast of enhancement (CE), a semi-quantitative parameter inversely estimating the CBV, were calculated pixel by pixel as the ratio of the maximum signal intensity drop during the passage of contrast agent (Sm) by the baseline pre-bolus signal intensity (So) (CE=Sm/Sox100) for right and left hemisphere on two axial images. Specifically, higher CE values correspond to lower CBV and viceversa Compared to normal controls, patients with schizophrenia had significantly higher bilateral hemisphere CE values (p=0.02) and inverse CE laterality index (p=0.02). This study showed abnormally reduced and inverse hemisphere CBV in a large population of patients with schizophrenia. Hypothetically, chronic low CBV may sustain neural hypoactivation and concomitant increase of free radicals, ultimately resulting in neuronal loss and cognitive impairments. Thus, altered intracranial hemodynamics may accompany brain atrophy and cognitive deficits, being a crucial factor in the pathophysiology of schizophrenia.  相似文献   
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The involvement of striatal somatostatin receptors (sst1, sst2 and sst4) in locomotor activity was investigated. Male Sprague–Dawley rats, 280–350 g, received in the striatum bilateral infusions of saline, somatostatin, and selective sst1, sst2, and sst4 ligands. Spontaneous locomotor activity was recorded for 60 min. The involvement of excitatory amino acid receptors (AMPA and NMDA) on somatostatin’s actions was also examined. Western blot analysis was employed for the identification of somatostatin receptors in striatal membranes. Somatostatin, sst2 and sst4, but not sst1, selective ligands increased rat locomotor activity in a dose-dependent manner. Blockade of AMPA and NMDA receptors reversed somatostatin’s actions. In conclusion, striatal somatostatin receptor activation differentially influence rat locomotor activity, while glutamatergic actions underlie the behavioral actions of somatostatin.  相似文献   
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Voriconazole (VRC) has activity against Aspergillus fumigatus, the most frequent cause of invasive aspergillosis in immunocompromised patients. The combination of VRC and A. fumigatus hyphae induced a more pronounced profile of expression of genes encoding inflammatory molecules in human monocytes than Aspergillus alone did. Herein, we provide further evidence of the potential mechanism underlying this immunomodulatory effect of VRC on human monocytes in response to A. fumigatus hyphae. A significant additive antifungal effect was shown when VRC was combined with monocytes against A. fumigatus hyphae. Both A. fumigatus hyphae and VRC induced pronounced profiles of mRNA and protein expression of Toll-like receptor 2 (TLR2) as well as tumor necrosis factor alpha (TNF-α) in THP-1 monocytic cells compared to untreated cells. The VRC-induced increase was greater than that induced by hyphae. The combination of VRC and hyphae increased mRNA and protein expression of TLR2 and TNF-α to even higher levels than did either VRC or hyphae alone. In contrast, TLR4 expression, both at the mRNA and protein levels, was not increased by either VRC or hyphae or their combination. In addition, significantly more NF-κB was translocated to the nuclei of THP-1 cells treated with VRC than untreated cells. While VRC induced more NF-κB than hyphae did, treatment with the combination of the two factors induced the greatest NF-κB expression. The pronounced profile of TLR2 signaling, TNF-α expression, and NF-κB activation in the presence of VRC suggests an immunomodulatory effect leading to a more efficient response to A. fumigatus.  相似文献   
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Nuclear factor (NF)-kappaB has been reported to be constitutively activated in various human neoplasms. However, its clinical significance in bladder urothelial carcinoma (UC) remains an unresolved issue. We conducted this study trying to elucidate the role of NFkappaB in bladder UC and its potential prognostic significance, by quantifying immunohistochemically the levels of p65/RelA expression in paraffin-embedded tissue from 116 patients. Some of the cases had previously been stained for cellular FLICE-like inhibitory protein (c-FLIP) and bcl-2. Seventy-four cases displayed concurrent cytoplasmic and nuclear immunoreactivity, whereas 18 only nuclear immunoexpression and 21 only cytoplasmic immunoexpression, and the remaining three cases were negative for p65/RelA. Nuclear p65/RelA expression was positively associated with tumour grade and T-category (p=0.0001 in both cases). In addition, cytoplasmic p65/RelA expression was lower in advanced T-category (p=0.0030). Moreover, p65/RelA nuclear expression was positively correlated with c-FLIP (p=0.0109) and bcl-2 (p=0.0452). p65/RelA nuclear expression adversely affected survival in both univariate and multivariate analysis in superficial (Ta-T1; p=0.0010 and p=0.0008) as well as in muscle-invasive carcinomas (T2-T4; p=0.0004 and p=0.0003). Our results demonstrate that NF-kappaB nuclear expression is correlated with histologic grade and T category in bladder UC. Moreover, NF-kappaB nuclear expression emerges as an independent prognosticator of adverse significance, conveying information beyond that obtained by standard clinicopathological prognosticators.  相似文献   
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Primary tuberculosis of the thyroid gland: report of three cases.   总被引:2,自引:0,他引:2  
We report on three cases with rapidly increasing thyroid masses who were referred with the provisional diagnosis of thyroid carcinoma. In the two cases, the diagnosis of tuberculosis was established after thyroidectomy, but in the third case diagnosis was made pre-operatively with acid fast bacilli (AFB) staining and culture from fine needle aspiration (FNA) material. Although rare, tuberculosis of the thyroid gland should be included in the differential diagnosis of thyroid masses. FNA, AFB staining and culture of the aspirate are important diagnostic tools in these cases.  相似文献   
70.
OBJECTIVE: To access health-related quality of life (HRQOL) in systemic sclerosis (SSc) patients using the World Health Organization Quality of Life Instrument, Short-Form (WHOQOL-BREF), and to identify the association between clinical, psychopathological, and personality parameters and SSc patients' HRQOL. METHODS: Fifty-six patients with SSc were compared with 72 patients with rheumatoid arthritis (RA), 43 with systemic lupus erythematosus (SLE), 34 with Sj?gren syndrome (SS), and 74 healthy controls. A wide range of clinical information was collected and the following self-report instruments were used: the WHOQOL-BREF, the General Health Questionnaire, the Symptom Distress Check List, the Hostility and Direction of Hostility Questionnaire, the Defense Style Questionnaire, and the Sense of Coherence scale. RESULTS: HRQOL perceived by SSc patients was significantly impaired compared with healthy controls. Initial examination of HRQOL across groups of rheumatology patients revealed similar HRQOL, but when age, pain, psychopathology, and coping strategies were taken into account, SSc patients had impaired physical health QOL in comparison with RA, SLE, and SS patients. Arthritis-related pain was closely associated with SSc patients' HRQOL. Elevated psychological distress symptoms as well as certain personality traits, such as maladaptive defenses and lower sense of coherence, were also associated with diminished HRQOL. CONCLUSIONS: Impaired psychological functioning is associated with diminished HRQOL in SSc, and consequently, treatment of depressive symptoms should be considered a priority. Moreover, assessment of HRQOL should only be used in conjunction with specific psychological distress measurements, to detect the influence of psychopathology on HRQOL.  相似文献   
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