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51.
Food homeostatic states (hunger and satiety) influence the cognitive systems regulating impulsive responses, but the direction and specific mechanisms involved in this effect remain elusive. We examined how fasting, and satiety, affect cognitive mechanisms underpinning disinhibition using a novel framework and a gamified test-battery. Thirty-four participants completed the test-battery measuring three cognitive facets of disinhibition: attentional control, information gathering and monitoring of feedback, across two experimental sessions: one after overnight fasting and another after a standardised meal. Homeostatic state was assessed using subjective self-reports and biological markers (i.e., blood-derived liver-expressed antimicrobial protein 2 (LEAP-2), insulin and leptin). We found that participants who experienced greater subjective hunger during the satiety session were more impulsive in the information gathering task; results were not confounded by changes in mood or anxiety. Homeostatic state did not significantly influence disinhibition mechanisms linked to attentional control or feedback monitoring. However, we found a significant interaction between homeostatic state and LEAP-2 on attentional control, with higher LEAP-2 associated with faster reaction times in the fasted condition only. Our findings indicate lingering hunger after eating increases impulsive behaviour via reduced information gathering. These findings identify a novel mechanism that may underpin the tendency to overeat and/or engage in broader impulsive behaviours.  相似文献   
52.
Free-roaming camels, especially those crossing national borders, pose a high risk for spreading Middle East respiratory syndrome coronavirus (MERS-CoV). To prevent outbreaks, active surveillance is necessary. We found that a high percentage of dromedaries in Tunisia are MERS-CoV seropositive (80.4%) or actively infected (19.8%), indicating extensive MERS-CoV circulation in Northern Africa.  相似文献   
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54.
BackgroundInjury to kidney podocytes often results in chronic glomerular disease and consecutive nephron malfunction. For most glomerular diseases, targeted therapies are lacking. Thus, it is important to identify novel signaling pathways contributing to glomerular disease. Neurotrophic tyrosine kinase receptor 3 (TrkC) is expressed in podocytes and the protein transmits signals to the podocyte actin cytoskeleton.MethodsNephron-specific TrkC knockout (TrkC-KO) and nephron-specific TrkC-overexpressing (TrkC-OE) mice were generated to dissect the role of TrkC in nephron development and maintenance.ResultsBoth TrkC-KO and TrkC-OE mice exhibited enlarged glomeruli, mesangial proliferation, basement membrane thickening, albuminuria, podocyte loss, and aspects of FSGS during aging. Igf1 receptor (Igf1R)–associated gene expression was dysregulated in TrkC-KO mouse glomeruli. Phosphoproteins associated with insulin, erb-b2 receptor tyrosine kinase (Erbb), and Toll-like receptor signaling were enriched in lysates of podocytes treated with the TrkC ligand neurotrophin-3 (Nt-3). Activation of TrkC by Nt-3 resulted in phosphorylation of the Igf1R on activating tyrosine residues in podocytes. Igf1R phosphorylation was increased in TrkC-OE mouse kidneys while it was decreased in TrkC-KO kidneys. Furthermore, TrkC expression was elevated in glomerular tissue of patients with diabetic kidney disease compared with control glomerular tissue.ConclusionsOur results show that TrkC is essential for maintaining glomerular integrity. Furthermore, TrkC modulates Igf-related signaling in podocytes.  相似文献   
55.
BackgroundBariatric surgery has become widely performed for treating patients with morbid obesity, and the age limits are being pushed further and further as the procedure proves safe. After massive weight loss, many of those patients seek body-contouring surgery for excess skin and fat.ObjectivesTo analyze the feasibility and the safety of abdominoplasty in patients older than 55 years old after bariatric surgery.SettingUniversity hospital medical center.MethodsWe performed a retrospective review of prospectively collected data from patients aged older than 55 years who had undergone abdominoplasty following massive weight loss due to a bariatric surgery at a single institution from 2004 to 2017. The data analyzed included age, gender, preoperative body mass index, associated interventions, co-morbidities, and postoperative complications.ResultsWe retrieved records for 104 patients; 85.6% percent of them were female, and the mean age was 60.1 ± 3.9 years old. Of the 104 patients, 21 (20.2%) underwent a sleeve gastrectomy and 77 (74%) underwent a Roux-en-Y gastric bypass. The mean interval between the bariatric surgery and the abdominoplasty was 33.6 ± 26.9 months. The mean preoperative weight and body mass index were 76.1 ± 14.5 kg and 28.9 ± 4.5 kg/m2, respectively. A total complication rate of 20% was observed. The only factor significantly associated with postoperative morbidity was the associated procedure (P = .03), when we performed another procedure at the same time as the abdominoplasty. Complications included postoperative bleeding in 5 patients (4.8%), seromas in 5 patients (4.8%), surgical site infections in 12 patients (11.5%), and wound dehiscence or ischemia in 2 patients (1.9%). No mortality occurred.ConclusionAbdominoplasty can be safely performed in carefully selected patients older than 55 years old after weight loss surgery, and does not present increased morbidity or mortality. We recommend that surgeons avoid adding concomitant procedures when possible, to decrease the risk of complications. It is also important to look at the patient’s previous maximum BMI levels, as a higher maximum BMI can predict higher postoperative risks and longer hospital stays.  相似文献   
56.
We have analysed DNA and RNA from 40 untreated head and neck cancers for amplified and overexpressed proto-oncogenes by Southern and Northern blot hybridisation. Coamplification but no expression of the bcl-1 and the hst genes was found in 12.5% of the patients. Furthermore, amplifications of c-myc were found in 10%, of Ha-ras and c-erbB-2 in 5%. c-erbB-2 amplification was accompanied by gene expression but no overexpression. Correlating our results with clinicopathological data of the patients amplifications were only found in stage III and IV disease (p=0.0164). No correlation was found between amplification and primary tumour site, histopathological differentiation of the tumours, response to induction chemotherapy, or survival. Our results indicate that oncogene amplification in advanced SCCHN reflects more the general genomic instability of advanced tumours than be a reason for tumour growth.  相似文献   
57.
Interleukin (IL)-9 is an emerging player in the pathogenesis of various chronic inflammatory diseases including bone disorders like rheumatoid arthritis (RA) and psoriatic arthritis. Recently, IL-9 was shown to enhance the osteoclast formation and their function in RA. However, the mechanisms by which IL-9 influences osteoclastogenesis are not known. Therefore, in this study we aimed to unravel the direct and indirect ways by which IL-9 can influence osteoclast formation. We used mouse bone marrow precursor cells for checking the effect of IL-9 on osteoclast differentiation and its function. Next, IL-9 induced signalling pathway were checked in the process of osteoclastogenesis. T cells play an important role in enhancing osteoclastogenesis in inflammatory conditions. We used splenic T cells to understand the impact of IL-9 on the functions of T effector (Teff) and regulatory T (Treg) cells. Furthermore, the effect of IL-9 mediated modulation of the T cell response on osteoclasts was checked using a coculture model of T cells with osteoclast precursors. We showed that IL-9 enhanced osteoclast formation and its function. We found that IL-9 activates STAT3, P38 MAPK, ERK1/2, NFκB and we hypothesize that it mediates the effect on osteoclastogenesis by accelerating mitochondrial biogenesis. Additionally, IL-9 was observed to facilitate the functions of pro-osteoclastogenic IL-17 producing T cells, but inhibits the function of anti-osteoclastogenic Treg cells. Our observations suggest that IL-9 can influence osteoclastogenesis directly by modulating the signalling cascade in the precursor cells; indirectly by enhancing IL-17 producing T cells and by reducing the functions of Treg cells.  相似文献   
58.
To investigate the fluxes of cationic amino acids beyond the proximal convolution, we micropunctured and microperfused superficial tubules of male Wistar rats in vivo et situ. In free-flow micropuncture experiments, the concentrations of endogenous L-arginine+, [Arg], and of intravenously infused L-homoarginine+, [HoArg], were determined by HPLC. Fluorescein isothiocyanatelabeled inulin was detected on-line in the same tubular fluid samples. To determine undirectional fluxes, radiolabeled Arg and inulin were (1) microperfused through short loops of Henle and (2) microinfused into different tubule segments to measure urinary recovery of the radiolabel. At a mean [Arg]plasma of 116 mol/l, [Arg] was 9.3 mol/l in the late proximal tubule (LPT), and 35.6 mol/l in the early distal tubule (EDT) corresponding to fractional deliveries (FD) of 0.055 in LPT and 0.078 in EDT. Fractional urinary excretion (FE) of Arg was 0.00033 (P<0.05 vs FDEDT). Infusion of HoArg (2.5 or 7.5 mol/min) led to respective mean [HoArg]plasma values of 1.44 and 3.73 mmol/l, and resulted in respective FDLPT values for HoArg of 0.23 and 0.53, respective FDEDT values of 0.29 and 0.41, and finally, respective FE values for HoArg of 0.25 and 0.58. When short loops of Henle were microperfused with 1 or 50 mmol/l [14C]Arg (+[3H]inulin), fractional recovery (FR) of 14C (relative to inulin) in the EDT was 0.13 and 0.36, respectively. During microinfusion of radiolabeled Arg (1 or 50 mmol/l) and inulin into LPT, the urinary FR of the radiolabel was 0.14, or 0.59, respectively. If 0.007, 1 or 50 mmol/l radiolabeled Arg were microinfused into EDT, the respective urinary FR of the radioactivity was 1.02, 1.10, or 1.01. Microperfusion of microinfusion of 1 mmol/l [14C]Arg plus 50 mmol/l HoArg resulted in a FREDT of 14C of 0.43 (loop, perfusion) and an FE for 14C of 0.69. Five conclusions can be drawn. First, cationic amino acids can enter and leave the lumen of short loops of Henle through specific carrier(s) at high rates, although, secondly, net transport is small or absent. Thus, medullary tubule cells can be supplied with Arg from the lumen of short loops of Henle for urea and nitric oxide production. Thirdly, the distal convolution of superficial nephrons and the collecting duct are not permeable to Arg. Thus, fourthly, the difference between FDEDT and urinary FE of Arg must be explained by an inter-nephron heterogeneity between deep and superficial nephrons. Finally, the process responsible for the different Arg handling in deep nephrons is not accessible to HoArg or, if so, it is saturated at millimolar concentrations.  相似文献   
59.
In HIV-infected patients, the outcome of counselling as the first step of a nutritional intervention programme was evaluated, in order to identify clinical and nutritional predictors for its efficacy. 75 HIV-infected patients were investigated, most with advanced disease. Nutritional status was determined by body weight, bioelectrical impedance and 7-day food intake record. Prior mean weight loss was 10% (range = +4% to -31%). Counselling facilitated weight gain in 40 75 patients (1-4 months later, overall mean difference +1.4 +/- 6.2%) and in 14 34 patients (8-11 months later, overall mean difference -1.4 +/- 9.0%). Weight changes correlated with changes in body cell mass (r(2) = .69, p < .001) and in body fat (r(2) = .29, p < 0.05), but not extracellular mass. Underlying conditions such as AIDS definition, fever, and diarrhoea correlated to prior weight loss (p < .001) but not to the outcome of counselling. Low energy intake (before counselling, < 31.5 kcal/kg) did not correlate to prior weight loss but it predicted further weight loss (p < 0.05 towards normal intake). High energy intake (> 38.5 kcal/kg) correlated (p < 0.05) with more prior weight loss but not with further weight changes. Nutritional counselling may be an effective first-line intervention for malnourished HIV infected patients. More than half of patients gain weight without other nutritional treatment. Whereas the severity of malnutrition is influenced by the underlying disease, fever, and diarrhoea, the course of weight change after nutritional intervention is not. Counselling may reduce the nutritional impact of these risk factors. In patients with low spontaneous intake, efficacy of counselling alone is limited, but it may help to identify those who require more invasive nutritional treatment.  相似文献   
60.
Periictal diffusion-weighted imaging in a case of lesional epilepsy   总被引:8,自引:1,他引:7  
PURPOSE: Diffusion-weighted MR imaging (DWI) has been used for the early diagnosis of acute ischemic lesions in humans and in animal models of focal status epilepticus. We hypothesized that DWI may be a sensitive, noninvasive tool for the localization of the epileptogenic area during the periictal period. METHODS: A periictal DWI study was performed on a 35-year-old patient during focal status epilepticus with repetitive prolonged focal motor seizures originating from a lesion in the right frontal lobe. DWI results were analyzed visually and by calculating apparent diffusion coefficient (ADC) maps. RESULTS: On DWI, a single area of signal increase (decrease in ADC) was found in the region of focal electrocorticographic seizures that was mapped intraoperatively. CONCLUSIONS: Ictal/postictal DWI may be a useful technique for seizure localization in patients with lesional epilepsy.  相似文献   
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