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21.

Background:

Monoamine reuptake inhibitors exhibit unique clinical profiles that reflect distinct engagement of the central nervous system (CNS) transporters.

Methods:

We used a translational strategy, including rodent pharmacokinetic/pharmacodynamic modeling and positron emission tomography (PET) imaging in humans, to establish the transporter profile of TD-9855, a novel norepinephrine and serotonin reuptake inhibitor.

Results:

TD-9855 was a potent inhibitor of norepinephrine (NE) and serotonin 5-HT uptake in vitro with an inhibitory selectivity of 4- to 10-fold for NE at human and rat transporters. TD-9855 engaged norepinephrine transporters (NET) and serotonin transporters (SERT) in rat spinal cord, with a plasma EC50 of 11.7ng/mL and 50.8ng/mL, respectively, consistent with modest selectivity for NET in vivo.Accounting for species differences in protein binding, the projected human NET and SERT plasma EC50 values were 5.5ng/mL and 23.9ng/mL, respectively. A single-dose, open-label PET study (4–20mg TD-9855, oral) was conducted in eight healthy males using the radiotracers [11C]-3-amino-4- [2-[(di(methyl)amino)methyl]phenyl]sulfanylbenzonitrile for SERT and [11C]-(S,S)-methylreboxetine for NET. The long pharmacokinetic half-life (30–40h) of TD-9855 allowed for sequential assessment of SERT and NET occupancy in the same subject. The plasma EC50 for NET was estimated to be 1.21ng/mL, and at doses of greater than 4mg the projected steady-state NET occupancy is high (>75%). After a single oral dose of 20mg, SERT occupancy was 25 (±8)% at a plasma level of 6.35ng/mL.

Conclusions:

These data establish the CNS penetration and transporter profile of TD-9855 and inform the selection of potential doses for future clinical evaluation.  相似文献   
22.
BackgroundHeart Failure with mid-range Ejection Fraction (HFmEF) was recently described by European and Brazilian guidelines on Heart Failure (HF). The ejection fraction (EF) is an important parameter to guide therapy and prognosis. Studies have shown conflicting results without representative data from developing countries.ObjectiveTo analyze and compare survival rate in patients with HFmEF, HF patients with reduced EF (HFrEF), and HF patients with preserved EF (HFpEF), and to evaluate the clinical characteristics of these patients.MethodsA cohort study that included adult patients with acute HF admitted through the emergency department to a tertiary hospital, reference in cardiology, in south Brazil from 2009 to 2011. The sample was divided into three groups according to EF: reduced, mid-range and preserved. A Kaplan-Meier curve was analyzed according to the EF, and a logistic regression analysis was done. Statistical significance was established as p < 0.05.ResultsA total of 380 patients were analyzed. Most patients had HFpEF (51%), followed by patients with HFrEF (32%) and HFmEF (17%). Patients with HFmEF showed intermediate characteristics related to age, blood pressure and ventricular diameters, and most patients were of ischemic etiology. Median follow-up time was 4.0 years. There was no statistical difference in overall survival or cardiovascular mortality (p=.0031) between the EF groups (reduced EF: 40.5% mortality; mid-range EF 39.7% and preserved EF 26%). Hospital mortality was 7.6%.ConclusionThere was no difference in overall survival rate between the EF groups. Patients with HFmEF showed higher mortality from cardiovascular diseases in comparison with HFpEF patients. (Arq Bras Cardiol. 2021; 116(1):14-23)  相似文献   
23.
Preclinical Research
This work was performed to assess the effects of intrathecal serotonin 2B (5‐HT2B) receptor antagonists in rats with neuropathic pain. With RS‐127445, its effect was also determined on 5‐HT2B receptor expression. Neuropathic pain was induced by L5/L6 spinal nerve ligation. Western blotting was used to determine 5‐HT2B receptor expression. Dose‐response curves with the 5‐HT2B receptor antagonists 2‐amino‐4‐(4‐fluoronaphth‐1‐yl)‐6‐isopropylpyridine (RS‐127445, 1–100 nmol) and 1‐[(2‐chloro‐3,4‐dimethoxyphenyl)methyl]‐2,3,4,9‐tetrahydro‐6‐methyl‐1H‐pyrido[3,4‐b]indole hydrochloride (LY‐266097, 1–100 nmol) were performed in rats. Tactile allodynia of the left hind paw (ipsilateral) was assessed for 8 h after compound administration. Intrathecal injection of the 5‐HT2B receptor antagonists RS‐127445 and LY‐266097 diminished spinal nerve ligation‐induced allodynia. In contrast, intrathecal injection of the 5‐HT2 receptor agonist (±)‐2,5‐dimethoxy‐4‐iodoamphetamine hydrochloride (DOI, 10 nmol) did not modify tactile allodynia induced by nerve ligation. L5/L6 nerve ligation increased expression of the 5‐HT2B receptors in the ipsilateral, but not contralateral, dorsal root ganglia. Furthermore, nerve injury also enhanced 5‐HT2B receptor expression in the ipsilateral dorsal part of the spinal cord. Intrathecal treatment with RS‐127445 (100 nmol) diminished spinal nerve injury‐induced increased expression of 5‐HT2B receptors in dorsal root ganglia and spinal cord. Our results imply that spinal 5‐HT2B receptors are present on sites related to nociception and participate in neuropathic pain. © 2014 Wiley Periodicals, Inc Drug Dev Res 76 : 31–39, 2015  相似文献   
24.
Purpose

The identification of subgroups of obstructive sleep apnea (OSA) is critical to understand disease outcome and treatment response and ultimately develop optimal care strategies customized for each subgroup. In this sense, we aimed to perform a cluster analysis to identify subgroups of individuals with OSA based on clinical parameters in the Epidemiological Sleep Study of São Paulo city (EPISONO). We aimed to analyze whether or not subgroups remain after 8 years, since there is not any evidence showing if these subtypes of clinical presentation of OSA in the same population can change overtime.

Methods

We used data derived from EPISONO cohort, which was followed over 8 years after baseline evaluation. All individuals underwent polysomnography, answered questionnaires, and had their blood collected for biochemical examinations. OSA was defined according to AHI?≥?15 events/h. Cluster analysis was performed using latent class analysis (LCA).

Results

Of the 1042 individuals in the EPISONO cohort, 68% agreed to participate in the follow-up study (n?=?712), and 704 were included in the analysis. We were able to replicate the OSA 3-cluster solution observed in previous studies: disturbed sleep, minimally symptomatic and excessively sleepy in both baseline (36%, 45% and 19%, respectively) and follow-up studies (42%, 43%, and 15%, respectively). The optimal cluster solution for our sample based on Bayesian information criterion (BIC) was 2 cluster for baseline (disturbed sleep and excessively sleepy) and 3 clusters for follow-up (disturbed sleep, minimally symptomatic, and excessively sleepy). A total of 45% of the participants migrated clusters between the two evaluations (and the factor associated with this was a greater delta-AHI (B?=????0.033, df?=?1, p?=?0.003).

Conclusions

The results replicate and confirm previously identified clinical clusters in OSA which remain in the longitudinal analysis, with some percentage of migration between clusters.

  相似文献   
25.
BACKGROUND: Non-alcoholic fatty liver disease is a common reason for hepatological consultation and may herald severe hepatic and extra-hepatic disease. The aetiopathogenesis of this condition is an area of increasing interest. AIM: To evaluate anthropometric and biochemical factors associated to non-alcoholic fatty liver disease in a case-control study. Methods. Demographic and biochemical data of 60 consecutive patients with bright liver absent-to-low alcohol consumption, no evidence of viral, genetic and autoimmune diseases, were compared to those of 60 age- and gender-matched historical controls without fatty liver by univariate and multiple logistic regression analysis. RESULTS: Patients were more often hypertriglyceridaemic, obese and diabetic than controls (p<.01). Mean values of alanine transaminase, gammaglutamyltranspeptidase, triglycerides, uric acid, fasting and log insulin, transferrin percent saturation and ferritin were significantly higher in the patients, while transferrin and quantitative insulin sensitivity check index, a quantitative insulin sensitivity index, were lower. No iron storage was found in those who underwent liver biopsy At univariate analysis the relative risk for non-alcoholic fatty liver disease significantly increased (p<0. 05) with increasing body mass index, fasting insulin, alanine transaminase, uric acid, triglycerides and gammaglutamyltranspeptidase; it decreased with increasing transferrin and quantitative insulin sensitivity check index. Multiple logistic regression analysis disclosed only fasting insulin and uric acid to be independent predictors of non-alcoholic fatty liver disease (p<0.05). CONCLUSIONS: Fasting insulin and serum uric acid levels indicating insulin resistance, but not indices of iron overload, are independent predictors of non-alcoholic fatty liver disease.  相似文献   
26.

Background

Laparoscopic hernia repair is used widely for the repair of incisional hernias. Few case studies have focussed on purely ‘incisional’ hernias. This multicentre series represents a collaborative effort and employed statistical analyses to provide insight into the factors predisposing to recurrence of incisional hernia after laparoscopic repair. A specific hypothesis (ie, laterality of hernias as well as proximity to the xyphoid process and pubic symphysis predisposes to recurrence) was also tested.

Methods

This was a retrospective study of all laparoscopic incisional hernias undertaken in six centres from 1 January 2004 to 31 December 2010. It comprised a comprehensive review of case notes and a follow-up using a structured telephone questionnaire. Patient demographics, previous medical/surgical history, surgical procedure, postoperative recovery, and perceived effect on quality of life were recorded. Repairs undertaken for primary ventral hernias were excluded. A logistic regression analysis was then fitted with recurrence as the primary outcome.

Results

A total of 186 cases (91 females) were identified. Median follow-up was 42 months. Telephone interviews were answered by 115/186 (62%) of subjects. Logistic regression analyses suggested that only female sex (odds ratio (OR) 3.53; 95% confidence interval (CI) 1.39–8.97) and diabetes mellitus (3.54; 1–12.56) significantly increased the risk of recurrence. Position of the defect had no statistical effect.

Conclusions

These data suggest an increased risk of recurrence after laparoscopic incisional hernia repair in females and subjects with diabetes mellitus. These data will help inform surgeons and patients when considering laparoscopic management of incisional hernias. We recommend a centrally hosted, prospectively maintained national/international database to carry out additional research.  相似文献   
27.
Digestive symptoms in young individuals: survey among medical students]   总被引:1,自引:0,他引:1  
The purpose of this study was to assess the frequency patterns of 8 digestive symptoms and related features, with regard to functional disorders, in young adults. A sample of 279 subjects, representing the student body at the Medical School of Brasília, filled up the self-report questionnaire. From 20% to 27% of subjects reported more than 6 episodes of one more of the following symptoms, within a 12-month period: indigestion, distension, constipation, heartburn, abdominal pain, and diarrhea. A higher prevalence of constipation in women was a significant (p < 0.05) difference between the sexes. Dyspepsia and irritable bowel syndrome (IBS) were identified by clinical criteria in 25% and 9% of subjects, respectively, while 4% disclosed the occurrence of an organic disease. About 30% of the subjects volunteered perceptions on the meaning of the symptoms, while 22% reported days of restricted activities ascribed to the symptoms. Days of restricted activities were significantly (p < 0.05) related to the number, the type (diarrhea, nausea and vomiting, and abdominal pain), and the IBS pattern of symptoms (but not to the dyspepsia pattern). In conclusion, a substantial proportion of subjects in this student group, contacted at the workplace, showed indexes of clinical dysfunction (recurrence of multiple symptoms), and of social dysfunction (days of restricted activity), which indicate persistent limitations on the digestive health status.  相似文献   
28.
Diabetes mellitus is a product of low insulin sensibility and pancreatic β-cell insufficiency. Rats with streptozotocin-induced diabetes during the neonatal period by the fifth day of age develop the classic diabetic picture of hyperglycemia, hypoinsulinemia, polyuria, and polydipsia aggravated by insulin resistance in adulthood. In this study, we investigated whether the effect of long-term treatment with melatonin can improve insulin resistance and other metabolic disorders in these animals. At the fourth week of age, diabetic animals started an 8-wk treatment with melatonin (1 mg/kg body weight) in the drinking water at night. Animals were then killing, and the sc, epididymal (EP), and retroperitoneal (RP) fat pads were excised, weighed, and processed for adipocyte isolation for morphometric analysis as well as for measuring glucose uptake, oxidation, and incorporation of glucose into lipids. Blood samples were collected for biochemical assays. Melatonin treatment reduced hyperglycemia, polydipsia, and polyphagia as well as improved insulin resistance as demonstrated by constant glucose disappearance rate and homeostasis model of assessment-insulin resistance. However, melatonin treatment was unable to recover body weight deficiency, fat mass, and adipocyte size of diabetic animals. Adiponectin and fructosamine levels were completely recovered by melatonin, whereas neither plasma insulin level nor insulin secretion capacity was improved in diabetic animals. Furthermore, melatonin caused a marked delay in the sexual development, leaving genital structures smaller than those of nontreated diabetic animals. Melatonin treatment improved the responsiveness of adipocytes to insulin in diabetic animals measured by tests of glucose uptake (sc, EP, and RP), glucose oxidation, and incorporation of glucose into lipids (EP and RP), an effect that seems partially related to an increased expression of insulin receptor substrate 1, acetyl-coenzyme A carboxylase and fatty acid synthase. In conclusion, melatonin treatment was capable of ameliorating the metabolic abnormalities in this particular diabetes model, including insulin resistance and promoting a better long-term glycemic control.  相似文献   
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