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151.

Purpose

Propranolol, a non-selective β-adrenergic receptor blocker, has been used for the treatment of the patients with hypertension for more than 50 years. There are several in vitro and in vivo evidences that β-adrenergic receptor antagonists inhibit proliferation and angiogenesis and also increase apoptosis in breast, skin, and colon cancers. The aim of this study was to investigate the cytotoxic and apoptotic effects of propranolol and the genes involved in propranolol-induced apoptosis in multiple myeloma cells.

Methods

Time-dependent antiproliferation and apoptotic effects of propranolol were subsequently determined by MTT cell proliferation assay, changes in caspase-3 activity, loss of mitochondrial membrane potential (MMP), and also the localization of phosphatidylserine in the plasma membrane. Changes in expression levels of NF-ΚB pathway were examined by qRT-PCR array.

Results

IC50 values of propranolol on U266 cells were calculated as 141, 100, and 75 μM after 24-, 48-, and 72-h propranolol exposure, respectively. There were significant increases in caspase-3 activity, loss of MMP, and increases in apoptotic cell population in response to propranolol in U266 cells in a time- and dose-dependent manner. There were increases in expression levels of BCL10, TRAF family members, interleukins, TLR1-4, TNFRSF10B, NF-κB, and the inhibitors of NF-κB genes, and significant decreases in expression levels of Bcl-2 in response to propranolol treatment were observed.

Conclusion

These results revealed that propranolol has antiproliferative and apoptotic effects on multiple myeloma cells. Being supported with in vivo analyses, propranolol can be a good and economical way to treat multiple myeloma patients.  相似文献   
152.
Background: A pancreaticoduodenectomy (PD) offers the only chance of a cure for pancreatic cancer and can be performed with low mortality and morbidity. However, little is known about outcomes of a PD in octogenarians. Methods: Differences in two groups of patients (Group Y, <80 and Group O, ≥80 year-old) who underwent a PD for pancreatic adenocarcinoma were analysed. Study end-points were length of post-operative stay, overall morbidity, 30-day mortality and overall survival. Results: There were 175 patients in Group Y (mean age 64 years) and 25 patients in Group O (mean age 83 years). Octogenarians had worse Eastern Cooperative Oncology Group (ECOG) Performance Status (PS ≥1: 90% vs. 51%) and American Society of Anesthesiology (ASA) score (>2: 71% vs. 47%). The two groups were similar in underlying co-morbidities, operative time, rates of portal vein resection, intra-operative complications, blood loss, pathological stage and status of resection margins. Octogenarians had a longer post-operative stay (20 vs. 14 days) and higher overall morbidity (68% vs. 44%). There was a single death in each group. At a median follow-up of 13 months median survival appeared similar in the two groups (17 vs. 13 months). Conclusions: As 30-day mortality and survival are similar to those observed in younger patients, a PD can be offered to carefully selected octogenarians.  相似文献   
153.
Background and aimsEctopic artery calcification has been documented in women with postmenopausal osteoporosis, in whom an imbalance in the number of circulating osteoprogenitor cells (OPCs) has been identified. Circulating OPCs form calcified nodules in vitro; however, it remains unknown whether an association exists between the number of circulating OPCs and aortic calcifications. We investigated the relationship between OPCs and aortic calcifications in women with postmenopausal osteoporosis.Methods and resultsThe number of circulating OPCs was quantified by FACS analysis in 50 osteoporotic postmenopausal women. OPCs were defined as CD15-/alkaline-phosphatase(AP)+ cells coexpressing or not CD34. Participants underwent measurement of markers of bone metabolism, bone mineral density and abdominal aortic calcium (AAC) by 64-slice computed tomography.Patients with AAC were older, had lower 25(OH)vitamin D levels and higher circulating CD15-/AP+/CD34- cells than those without AAC. Significant correlates of AAC included age (rho = 0.38 p = 0.006), calcium (rho = 0.35 p = 0.01), 25(OH)vitamin D (rho = ?0.31, p = 0.03) and the number of CD15-/AP+/CD34- cells (rho = 0.55 p < 0.001). In regression analyses, the log-transformed number of CD15-/AP+/CD34- cells was associated with the presence (OR = 6.45, 95% CI 1.03–40.1, p = 0.04) and severity (β = 0.43, p < 0.001) of AAC, independent of age, 25(OH)vitamin D, calcium and other potential confounders. Patients with low 25(OH)vitamin D and high CD15-/AP+/CD34- cells had higher median AAC than other patients (1927/μL, 862–2714/μL vs 147/μL, 0–1665/μL, p = 0.003).ConclusionIn women with postmenopausal osteoporosis, the number of circulating CD15-/AP+/CD34- cells is significantly associated with increased aortic calcifications, that appear to be correlated also with reduced 25(OH)vitamin D levels.  相似文献   
154.
Cardiac parasympathetic control has prognostic significance in heart failure, but the control mechanisms of this system remain poorly defined. We have demonstrated previously a facilitatory role for nitric oxide (NO) in the parasympathetic control of heart rate in young healthy human subjects. In view of the complex abnormalities of regional NO activity observed in chronic heart failure, we now aim to establish if this mechanism is active in subjects with this condition. Groups of 12 heart failure patients [NYHA class II-III; mean age 52 years (range 38-67 years)] and 12 age/sex-matched healthy control subjects [mean age 50 years (range 36-62 years)] were studied. Heart rate variability and baroreflex sensitivity were measured during inhibition of endogenous NO production with N(G)-monomethyl-l-arginine (l-NMMA; 3 mg.h(-1).kg(-1)) and during administration of an equipressor dose of the control vasoconstrictor phenylephrine (12-36 microg.h(-1).kg(-1)). Basal levels of nitrate+nitrite were measured in the plasma as an indication of systemic NO production. In the heart failure patients, despite an equal rise in blood pressure with both drugs, high-frequency indices of heart rate variability increased less with l-NMMA than with phenylephrine: RMSSD (root mean square of successive RR-interval differences) increased by 4+/-2 compared with 26+/-8 ms (P<0.001) and high-frequency power increased by 97+/-62 compared with 1372+/-861 ms(2) (P<0.001). The increases in cross-spectral baroreflex sensitivity were also lower with l-NMMA than with phenylephrine [high-frequency alpha-index, 2.2+/-1.3 and 12.6+/-3.8 ms/mmHg respectively (P<0.001); low-frequency alpha-index, 1.3+/-0.9 and 4.3+/-1.7 ms/mmHg respectively (P<0.05)]. Healthy subjects showed a similar discrepancy in the response of high-frequency indices of heart rate variability to the two drugs, although baroreflex sensitivity responses were significantly different only for the high-frequency alpha-index. Levels of plasma nitrate+nitrite were significantly higher in the heart failure patients compared with controls. These data demonstrate that baroreflex-mediated cardiac parasympathetic activation in human heart failure, as in health, is dependent upon endogenous NO synthesis.  相似文献   
155.
Detoxification from drug abuse is strongly threatened by the occurrence of renewed episodes of drug intake. In human addicts, relapse to drug seeking may take place even after a considerably long period from the last drug consumption. Over the last decade, the endocannabinoid system has received remarkable attention due to its unique features, including its rewarding properties closely resembling those of the most commonly abused substances and its multiple therapeutic implications. Although limited at present, evidence is now emerging on a possible participation of the endogenous cannabinoid system in the regulation of relapsing phenomena. Both stimulation and blockade of the central cannabinoid CB-sub1 receptor have proved to play an important role in drug- as well as in cue-induced reinstatement of drug seeking behavior. Indeed, while CB-sub1 receptor stimulation may elicit relapse not only to cannabinoid seeking but also to cocaine, heroin, alcohol and methamphetamine, this effect is significantly attenuated, when not fully prevented, by pretreatment with the CB-sub1 receptor antagonist rimonabant. However, corroborating data on the involvement of the cannabinoid system in stress-induced reinstatement are still rather scarce. The present review attempts to collect data obtained from different laboratories using diverse experimental approaches, to provide a comprehensive picture of the recent evidence of a relationship between the cannabinoid system and the neurobiological mechanisms leading to relapse. For each class of abused drugs, the conspicuous progress made in delineating the role of the endocannabinoid system in relapse to drug seeking has been examined by placing particular emphasis on the findings obtained from behavioral studies. After summarizing findings and implications emerging from the reviewed studies, we conclude by briefly discussing what information is still missing and how missing information might be obtained.  相似文献   
156.
The capacity for short-term adaptation is a well-established property of the horizontal (H) and vertical (V) components of saccades. It allows these directional components, which clearly serve the goal of foveation, to maintain their precision even under changing circumstances. Torsional (T) saccade components, on the other hand, which deal with the orientation of the target on the fovea, have hardly been investigated in adaptation experiments. They appear to be severely restricted by Listing's law during fixations and saccades. The main purpose of Listing's law is far from obvious but could be visual or oculomotor. Better knowledge of the adaptive capacity of the saccadic system in the torsional direction could throw new light on the functional significance of this interesting neural strategy. To study short-term plasticity in the torsional components of saccades, binocular 3D-eye positions were measured, using magnetic search foils. Five normal human subjects were instructed to make uni-directional refixation saccades, while they viewed a large visual scene. To induce a change in the torsional component, the complete stimulus was rapidly rotated during these saccades. We thoroughly investigated the torsional responses of the saccadic system, to see if any short-term adaptive response in torsional direction was induced, in which case the notion of a visual purpose for Listing's law would be strengthened. In none of our experiments, however, did we find any clear adaptive response in torsional direction. To further investigate the reliability of this result and to ascertain that our experimental conditions allowed classical gain adaptation, we also did experiments designed to achieve a combination of torsional adaptation and classic gain shortening in one of the directional components. While gain adaptation was very obvious, none of the experiments provided evidence for a short-term effect in torsion. We conclude that our experiments do not support a purely visual basis for Listing's law.  相似文献   
157.
158.
We present clinical, radiological, and histopathological findings and treatment results of two infants with orbital eosinophilic granuloma. Both patients presented at 1 year of age with unilateral proptosis, periorbital edema, and a superotemporally located, ill-defined orbital mass on computed tomographic (CT) imaging, with bone erosion in one patient. After subtotal excision, histopathological examination revealed eosinophilic granuloma, and the proptosis resolved with no sign of orbital tumor recurrence or systemic involvement at 12 and 23 months follow-up. Eosinophilic granuloma is a rare childhood orbital tumor that may or may not present with osteolytic change.  相似文献   
159.
We performed a service-based epidemiological study of primary blepharospasm in the island of Sardinia (Italy). Due to its favorable geographical location, we are confident we will provide reliable data from patients seeking botulinum toxin treatment. A total of 53 patients were assessed. Prevalence was estimated to be 32.2 per 1 million (95% confidence interval, 23.0-40.8). These results are in line with those obtained in other similar surveys, that is, record-based, and performed in various European regions such as Northern England, the Munich area, as well as the Epidemiologic Study of Dystonia in Europe.  相似文献   
160.
The renal excretion of stevioside, a glycoside extracted from the leaves of Stevia rebaudiana, and its effect on renal excretion of several substances, was studied through clearance techniques in Wistar rats. After a control period, stevioside was infused iv at four concentrations (4, 8, 12, and 16 mg/kg). During all the experiments no significant changes in inulin clearance (CIn) were observed. The stevioside infusion induced a significant increase in the p-aminohippuric acid clearance (CPAH), fractional sodium excretion (FeNa+), urinary flow as percent of glomerular filtration rate (V/GFR), and glucose clearance (CG) when compared to controls, but these effects were absent with the dose of 4 mg/kg. The stevioside clearance (CS) was higher than the CIn and lower than the CPAH at all the doses employed in this study. These results indicate that the stevioside is secreted by renal tubular epithelium and induces diuresis and natriuresis and a fall in renal tubular reabsorption of glucose.  相似文献   
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