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21.
22.
Crohn's disease (CD) is an inflammatory chronic bowel disorder; it can involve the whole gastrointestinal tract, but its localization in the ileum or colon is most common. The reference standard for the diagnosis of CD is ileocolonoscopy with histologic assessment. The reference standard for the detection of any complications is surgery. However, imaging techniques have an important role both in the detection/localization of CD and in the follow-up of CD patients. In the last few years, the technical development of ultrasound equipment, the advent of new technologies such as elastography and mostly the increased expertise of sonographers have boosted the role of bowel ultrasound in assessment of the gastrointestinal tract. In fact, bowel ultrasound is particularly attractive thanks to its widespread availability, non-invasiveness, low cost and good reproducibility, as it can be easily repeated during follow-up. The aim of this article is to provide an extensive overview of the actual role of bowel ultrasound in the detection and follow-up of patients with CD.  相似文献   
23.
The use of bowel ultrasonography (US) for the evaluation of gut diseases has increased in recent years and has been proven to provide a widely available, non-invasive and inexpensive method for the initial work-up and follow-up of different intestinal diseases, limited mostly by technical challenges posed by the patient's anatomy. The present review aims to provide an extensive overview of the main pathologic features at US examination of intestinal diseases other than inflammatory bowel disease, both acute (e.g., acute appendicitis, colonic diverticulitis, infectious diseases and ischemic conditions) and chronic (e.g., celiac disease, cystic fibrosis and other enterocolites). The identification of typical US features may help in the diagnostic process and guide the treatment approach. Therefore, the application of knowledge of the US appearance of gastrointestinal diseases is of relevance in enabling greater diagnostic performance and better patient management.  相似文献   
24.
Background:  Addictive drugs activate extracellular signal regulated kinase (ERK) in brain regions critically involved in their affective and motivational properties. The aim of this study was to demonstrate the ethanol-induced activation of ERK in the nucleus accumbens (Acb) and in the extended amygdala [bed nucleus of the stria terminalis lateralis (BSTL) and central nucleus of the amygdala (CeA)] and to highlight the role of dopamine (DA) D1 receptors in these effects.
Methods:  Ethanol (0.5, 1, and 2 g/kg) was administered by gavage and ERK phosphorylation was determined in the nucleus Acb (shell and core), BSTL, and CeA by immunohistochemistry. The DA D1 receptor antagonist, SCH 39166 (SCH) (50 μg/kg), was administered 10 minutes before ethanol (1 g/kg).
Results:  Quantitative microscopic examination showed that ethanol, dose-dependently increased phospho-ERK immunoreactivity (optical and neuronal densities) in the shell and core of nucleus Acb, BSTL, and CeA. Pretreatment with SCH fully prevented the increases elicited by ethanol (1 g/kg) in all brain regions studied.
Conclusions:  The results of this study indicate that ethanol, similar to other addictive drugs, activates ERK in nucleus Acb and extended amygdala via a DA D1 receptor-mediated mechanism. Overall, these results suggest that the D1 receptors/ERK pathway may play a critical role in the motivational properties of ethanol.  相似文献   
25.
Summary Since copper [Cu(II)] is a necessary cofactor for both intra-mitochondrial enzymes involved in energy production and hydroxyl scavenger enzymes, two hypothesised mechanisms for action of interleukin-Iβ (IL-1β), we studied whether CU(II) addition could prevent the inhibitory effect of IL-1β on insulin release and glucose oxidation in rat pancreatic islets. Islets were incubated with or without 50 U/ml IL-1β, in the presence or absence of various concentrations of Cu(II)-GHL (Cu(II) complexed with glycyl-l-histidyl-l-lysine, a tripeptide known to enhance copper uptake into cultured cells). CuSO4 (1–1000 ng/ml) was used as a control for Cu(II) effect when present as an inorganic salt. At the end of the incubation period, insulin secretion was evaluated in the presence of either 2.8 mmol/l (basal insulin secretion) or 16.7 mmol/l glucose (glucose-induced release). In control islets basal insulin secretion was 92.0±11.4 pg · islet−1 h−1 (mean ± SEM,n=7) and glucose-induced release was 2824.0±249.0 pg · islet−1 h−1. In islets pre-exposed to 50 U/ml IL-1β, basal insulin release was not significantly affected but glucose-induced insulin release was greatly reduced (841.2±76.9,n=7,p<0.005). In islets incubated with IL-1β and Cu-GHL (0.4 μmol/l, maximal effect) basal secretion was 119.0±13.1 pg · islet−1 h−1 and glucose-induced release was 2797.2±242.2, (n=7,p<0.01 in respect to islets exposed to IL-1β alone). In contrast to data obtained with Cu(II)-GHL, increasing concentrations of CuSO4 (up to 10 μmol/l) did not influence the inhibitory effect of IL-1β on glucose-stimulated insulin release. Glucose oxidation (in the presence of 16.7 mmol/l glucose) was 31.5±2.4 pmol · islet−1·90min−1 in control islets and 7.0±0.9 (p<0.01) in IL-1β-exposed islets. In islets exposed to IL-1β and Cu-GHL glucose oxidation was similar to control islets (31.9±1.9). In contrast, Cu-GHL did not prevent the IL-1β-induced increase in nitric oxide production. Nitrite levels were 5±1.7, 26±5 and to 29±4 pmol · islet−1·48 h−1 (mean ± SEM,n=5) in the culture medium from control IL-1β and IL-1β+Cu-GHL exposed islets, respectively. These data indicate that the Cu(II) complexed to GHL is able to prevent the inhibitory effects of IL-1β on insulin secretion and glucose oxidation, but not on NO production. The mechanism of action of Cu-GHL is still unclear, but it might restore the activity of the enzymatic systems inhibited by IL-1β. [Diabetologia (1995) 38∶39–45]  相似文献   
26.
Anorchia, or the "vanishing testis syndrome," is characterized by the absence of testis in a 46,XY individual with a male phenotype. The etiology is unknown; however, the familial occurrence of the disease and the association of this phenotype with 46,XY gonadal dysgenesis has led to the suggestion that genetic factors, which play a role in testicular determination, may be involved. Alternatively, exploratory laparoscopy has suggested that anorchia may be caused by a prenatal testicular vascular accident associated with torsion during testicular descent. We screened a cohort of 14 boys with bilateral anorchia for mutations in the Y chromosome-linked testis-determining gene SRY (sex-determining region, Y chromosome); in the gene necessary for correct testicular descent, INSL3; and in the gene of its receptor (LGR8). Mutations in the INSL3 gene and the LGR8 T222P mutation are known to cause cryptorchidism. We confirmed previous reports that mutations in the SRY gene are not associated with anorchia. Although a common polymorphism was identified in the INSL3 gene, no mutations were observed. The recurrent T222P mutation in the LGR8 gene was not found in any of the patients. These data show for the first time a lack of association between genetic factors necessary for correct testicular descent and anorchia.  相似文献   
27.
The relationship between chronic moderate beerconsumption and oxidative stress was studied in rats.Animals were fed three different isocaloric diets forsix weeks: a beercontaining diet (30% w/w), an ethanol-supplemented diet (1.1 g/100 g, thesame as in the beer diet) and an alcohol-free basaldiet. At the end of the feeding period, rats wereanalyzed for plasma and liver oxidative status. Somelivers were isolated and exposed toischemiareperfusion to assess the additional oxidativestress determined by reperfusion. No significantdifferences in plasma antioxidant status were foundamong the three dietary groups. Lipoproteins from the beer group,however, showed a greater propensity to resist lipidperoxidation. Ischemia caused a decrease in liver energyand antioxidant status in all groups. Nevertheless, ATP was lower in the livers of rats exposed tothe ethanol diet. During reperfusion, lipoperoxidationincreased significantly in all groups. However, liversobtained from ethanoltreated rats showed the higher formation of lipoperoxides. Inconclusion, a moderate consumption of beer in awell-balanced diet did not appear to cause oxidativestress in rats; moreover, probably through its minorcomponents, beer could attenuate the oxidative action ofethanol by itself.  相似文献   
28.
Fibroblast growth factors (FGFs) exert autocrine/paracrine functions in prostate cancer by stimulating angiogenesis and tumour growth. Here dihydrotestosterone (DHT) up‐regulates FGF2 and FGF8b production in murine TRAMP‐C2 prostate cancer cells, activating a FGF‐dependent autocrine loop of stimulation. The soluble pattern recognition receptor long pentraxin‐3 (PTX3) acts as a natural FGF antagonist that binds FGF2 and FGF8b via its N‐terminal domain. We demonstrate that recombinant PTX3 protein and the PTX3‐derived pentapeptide Ac‐ARPCA‐NH2 abolish the mitogenic response of murine TRAMP‐C2 cells and human LNCaP prostate cancer cells to DHT and FGFs. Also, PTX3 hampers the angiogenic activity of DHT‐activated TRAMP‐C2 cells on the chick embryo chorioallantoic membrane (CAM). Accordingly, human PTX3 overexpression inhibits the mitogenic activity exerted by DHT or FGFs on hPTX3_TRAMP‐C2 cell transfectants and their angiogenic activity. Also, hPTX3_TRAMP‐C2 cells show a dramatic decrease of their angiogenic and tumourigenic potential when grafted in syngeneic or immunodeficient athymic male mice. A similar inhibitory effect is observed when TRAMP‐C2 cells overexpress only the FGF‐binding N‐terminal PTX3 domain. In keeping with the anti‐tumour activity of PTX3 in experimental prostate cancer, immunohistochemical analysis of prostate needle biopsies from primary prostate adenocarcinoma patients shows that parenchymal PTX3 expression, abundant in basal cells of normal glands, is lost in high‐grade prostatic intraepithelial neoplasia and in invasive tumour areas. These results identify PTX3 as a potent FGF antagonist endowed with anti‐angiogenic and anti‐neoplastic activity in prostate cancer. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
29.
A deficit in pre‐cognitively mirroring other people''s actions and experiences may be related to the social impairments observed in autism spectrum disorder (ASD). However, it is unclear whether such embodied simulation deficits are unique to ASD or instead are related to motor impairment, which is commonly comorbid with ASD. Here we aim to disentangle how, neurologically, motor impairments contribute to simulation deficits and identify unique neural signatures of ASD. We compare children with ASD (N = 30) to children with Developmental Coordination Disorder (DCD; N = 23) as well as a typically developing group (N = 33) during fMRI tasks in which children observe, imitate, and mentalize about other people''s actions. Results indicate a unique neural signature in ASD: during action observation, only the ASD group shows hypoactivity in a region important for simulation (inferior frontal gyrus, pars opercularis, IFGop). However, during a motor production task (imitation), the IFGop is hypoactive for both ASD and DCD groups. For all tasks, we find correlations across groups with motor ability, even after controlling for age, IQ, and social impairment. Conversely, across groups, mentalizing ability is correlated with activity in the dorsomedial prefrontal cortex when controlling for motor ability. These findings help identify the unique neurobiological basis of ASD for aspects of social processing. Furthermore, as no previous fMRI studies correlated brain activity with motor impairment in ASD, these findings help explain prior conflicting reports in these simulation networks.  相似文献   
30.
Neurological Sciences - Although recent data show that SARS-CoV-2 infection seems to affect the central nervous system (CNS), little is known about the neuropsychiatric effects resulting from this...  相似文献   
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