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101.
The muscarinic M(2) receptor was split at the third cytoplasmic loop into two fragments: the one containing the first five transmembrane regions and the N-terminal part of the third cytoplasmic loop was named M(2trunk), while the other, which contained the last two transmembrane regions and the C-terminal part of the third cytoplasmic loop, was named M(2tail). As seen in many other G protein-coupled receptors, when these two fragments were transfected together in COS-7 cells they rescued the pharmacological profile and the functional activity of the wild-type M(2) receptor. Conversely, N-[(3)H]methylscopolamine ([(3)H]NMS) association binding experiments showed a substantial difference between the wild-type M(2) and the split M(2trunk)/M(2tail) receptors. The progression of the association binding kinetic of the M(2trunk)/M(2tail) receptor was strictly dependent upon the amount of the fragment DNA transfected. When the amount of transfected DNA was 4 microg/plate and the B(max) of [(3)H]NMS at equilibrium was around 200 fmol/mg protein the form of the association was that of classical saturation, but when the amount of transfected DNA was lower the [(3)H]NMS association reached a maximum binding point and then declined to a lower equilibrium binding level. The form of the association was temperature-dependent: as the temperature was lowered, the maximum binding point tended to be higher. We suggest that this peculiar form of the [(3)H]NMS association binding to the muscarinic M(2trunk)/M(2tail) receptor is attributable to a less stable interaction between the trunk and the tail fragments of the split receptor.  相似文献   
102.
Prader-Willi syndrome (PWS) is a multi-system disorder characterized clinically by abnormal mental and physical development. PWS patients have a deletion in an imprinted region on paternal chromosome 15 (15q11-13), maternal disomy for this segment, or rarely, a chromosomal imprinting center deletion that gives rise to suppression of the equivalent paternal genes. Within the affected segment of chromosome 15 are genes encoding the alpha(5), beta(3) and gamma(3) subunits of the gamma-aminobutyric acid type-A (GABA(A)) receptor. Therefore, altered neurobehavioral function could arise in PWS due directly to altered GABA(A) receptor composition and expression, or alternatively, from brain developmental and maturational effects of these or other genes in the imprinted region. The aim of the present study was to assess cerebral GABA(A) receptors in PWS with the use of positron emission tomography of the benzodiazepine binding site employing [11C]flumazenil ([11C]FMZ). A reduction in [11C]FMZ binding was found predominantly in the cingulate, frontal and temporal neocortices and insula in six adult PWS patients compared to nine normal subjects. A possible role for the deleted beta(3) subunit gene in PWS is supported in part by the wide cortical distribution of its mRNA expression and the effects of experimental knockouts on benzodiazepine binding described in prior studies. Altered GABA(A) receptor composition or number in these cortical regions may account for neurobehavioral abnormalities in PWS including mild mental retardation, poor impulse control, and impaired responses to somatic pain.  相似文献   
103.
The accuracy of the double-contrast enema for the diagnosis of polypoid lesions in the presence or absence of diverticula was evaluated by retrospectively reviewing the medical records of 202 patients subjected to examination and endoscopy. Analysis of the data on 215 polypoid lesions showed that (a) the diagnostic accuracy of the examination is not affected significantly by the presence of diverticula; (b) the sensitivity of the examination is highly dependent on the size of the polyps (smaller or larger than 0.5 cm) but not on the form (sessile or pedunculated); and (c) the positive predictive value is higher in patients without diverticula. The doublecontrast enema was confirmed to be a valid method for the diagnosis of polypoid lesions.  相似文献   
104.
BACKGROUND/AIMS: The outcome of endoscopic biliary stent insertion for postoperative bile duct stenosis was retrospectively evaluated. METHODOLOGY: Fifty-seven patients with biliary stenosis from laparoscopic cholecystectomy were included from February 1992 to January 2000. One to three stents were inserted for an average of 12.4 months, with stent exchange every 3 months to avoid cholangitis caused by clogging. RESULTS: Successful stent insertion was achieved in 43/57 (75.4%) patients. Stent insertion failed in 10 patients with complete and in 4 patients with incomplete biliary obstruction. Early complications occurred in 4 patients. Late complications occurred in 5/43 patients. Five patients experienced recurrence of stenosis. CONCLUSIONS: Endoscopic treatment should be the initial management of choice for postoperative bile duct stenosis.  相似文献   
105.
106.
Purpose: To prospectively evaluate the albumin/globulin ratio (AGR), neutrophil/lymphocyte ratio (NLR), and platelet/lymphocyte ratio (PLR) diagnostic and prognostic predictive value in a stratified population of prostate cancer (PC) cases. Methods: Population was divided based on the clinical and histologic diagnosis in: Group A: benign prostatic hyperplasia (BPH) cases (494 cases); Group B: all PC cases (525 cases); Group B1: clinically significant PC (426 cases); Group B2: non-metastatic PC (416 cases); Group B3: metastatic PC (109 cases). NLR, PLR, and AGR were obtained at the time of the diagnosis, and only in cases with PC considered for radical prostatectomy, determinations were also repeated 90 days after surgery. For each ratio, cut-off values were determined by receiver operating characteristics curve (ROC) analysis and fixed at 2.5, 120.0, and 1.4, respectively, for NLR, PLR, and AGR. Results: Accuracy in predictive value for an initial diagnosis of clinically significant PC (csPC) was higher using PLR (0.718) when compared to NLR (0.220) and AGR (0.247), but, despite high sensitivity (0.849), very low specificity (0.256) was present. The risk of csPC significantly increased only according to PLR with an OR = 1.646. The percentage of cases with metastatic PC significantly increased according to high NLR and high PLR. Accuracy was 0.916 and 0.813, respectively, for NLR and PLR cut-off, with higher specificity than sensitivity. The risk of a metastatic disease increased 3.2 times for an NLR > 2.5 and 5.2 times for a PLR > 120 and at the multivariate analysis. Conclusion: PLR and NLR have a significant predictive value towards the development of metastatic disease but not in relation to variations in aggressiveness or T staging inside the non-metastatic PC. Our results suggest an unlikely introduction of these analyses into clinical practice in support of validated PC risk predictors.  相似文献   
107.
We present a new mobile platform to be used in clinical trials aimed at both collecting data and assessing new technologies and treatments for diabetes care. The main components of the platform are a mobile app, that automatically collects data from continuous glucose monitoring sensors and activity trackers, and also allows users to manually log daily events; a cloud database for safe data storage; a web interface, which allows clinicians to monitor patients’ status in real-time. The platform is modular and highly customizable for a multitude of purposes in clinical research. Preliminary tests performed for daily-life data gathering by both clinicians and users are extremely encouraging.  相似文献   
108.
Background: During the COVID-19 pandemic, the risk of SARS-CoV-2 infection, the public health measures of social distancing, the freedom limitations, quarantine, and the enforced homeworking under the lockdown period, as well as medical causes including COVID-19 infection per se, may have caused major emotional distress, especially in the most vulnerable patients. We aimed to evaluate the variations in the number of admissions due to Takotsubo syndrome (TTS) during the COVID-19 pandemic in the Veneto region. Methods: We retrospectively reviewed and analyzed the number of admissions because of TTS in 13 Divisions of Cardiology located in the Veneto region, the northeastern area of Italy, covering a population of more than 2.5 million inhabitants, during the two major pandemic waves of COVID-19 (the first between 15 March and 30 April 2020 and the second between 15 November and 30 December 2020) that occurred in 2020. Results: In total, 807 acute coronary syndromes were admitted in the 13 enrolling hospitals. Among these, 3.9% had TTS. Compared to the corresponding 2018 and 2019 time periods, we observed a significant increase in the number of TTS cases (+15.6%, p = 0.03 and +12.5%, p = 0.04, comparing 2018 to 2020 and 2019 to 2020, respectively). Geographical distribution of the TTS cases reflected the broad spread of the SARS-CoV-2 infection with a significant direct relationship between TTS incidence and the number of COVID-19 infections according to Pearson’s correlation (r = 0.798, p < 0.001). Conclusions: The higher incidence of TTS during the 2020 COVID-19 pandemic waves, especially in the areas that were hit hardest in terms of morbidity and mortality by the SARS-CoV-2 infection, suggest a strong direct and/or indirect role of COVID-19 in the pathogenesis of TTS.  相似文献   
109.
The prevention of chemotherapy-induced alopecia still represents an urgent need for every day clinical practice. In this regard, this prospective single-center study included breast cancer (BC) patients who underwent a scalp cooling device (Dignicap®) during (neo)adjuvant chemotherapy with the aim to evaluate the efficacy and safety of this device in preventing alopecia. One hundred and seventy-eight patients (median age 43 years) were enrolled. The chemotherapy regimen included anthracycline and taxane-based chemotherapy (68.1%), docetaxel and cyclophosphamide (25.8%), anthracycline and taxane-based plus carboplatin (3.9%), and paclitaxel alone (2.2%). In 25.3% of cases, a dose dense schedule was used. Overall, the success rate was 68.0%: 100% in paclitaxel alone, 87.0% in docetaxel-cyclophosphamide, 59.5% in anthracycline and taxane, and 71.4% in the sequential regimen plus carboplatin group (anthracycline and taxane-based chemotherapy versus taxane-based chemotherapy, p ≤ 001. No difference in terms of hair preservation between dose-dense or standard schedule was found (p = 0.557). Early discontinuation of the scalp cooling was observed in 50 patients (28.1%). Although 138 patients (77.5%) experienced adverse events, 70.2% of patients were satisfied with this device. In conclusion, this large prospective study confirmed the helpful effect of the scalp cooling system in preventing alopecia in BC patients also undergoing sequential anthracyclines and taxane-based chemotherapy.  相似文献   
110.
We aimed to describe body composition changes up to 6–7 months after severe COVID-19 and to evaluate their association with COVID-19 inflammatory burden, described by the integral of the C-reactive protein (CRP) curve. The pectoral muscle area (PMA) and density (PMD), liver-to-spleen (L/S) ratio, and total, visceral, and intermuscular adipose tissue areas (TAT, VAT, and IMAT) were measured at baseline (T0), 2–3 months (T1), and 6–7 months (T2) follow-up CT scans of severe COVID-19 pneumonia survivors. Among the 208 included patients (mean age 65.6 ± 11 years, 31.3% females), decreases in PMA [mean (95%CI) −1.11 (−1.72; −0.51) cm2] and in body fat areas were observed [−3.13 (−10.79; +4.52) cm2 for TAT], larger from T0 to T1 than from T1 to T2. PMD increased only from T1 to T2 [+3.07 (+2.08; +4.06) HU]. Mean decreases were more evident for VAT [−3.55 (−4.94; −2.17) cm2] and steatosis [L/S ratio increase +0.17 (+0.13; +0.20)] than for TAT. In multivariable models adjusted by age, sex, and baseline TAT, increasing the CRP interval was associated with greater PMA reductions, smaller PMD increases, and greater VAT and steatosis decreases, but it was not associated with TAT decreases. In conclusion, muscle loss and fat loss (more apparent in visceral compartments) continue until 6–7 months after COVID-19. The inflammatory burden is associated with skeletal muscle loss and visceral/liver fat loss.  相似文献   
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