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81.
Fahad D. Alosaimi Ebtihaj O. Fallata Mohammed Abalhassan Abdulhadi Alhabbad Nasser Alzain Bandar Alhaddad 《International journal of psychiatry in clinical practice》2013,17(4):274-281
AbstractObjectives: Hyperprolactinemia is a common adverse event associated with psychotropic medications (mainly antipsychotics) used in the management of schizophrenia and bipolar disorders. The aim of this study was to estimate the prevalence of hyperprolactinemia in psychiatric patients and to evaluate its association with various psychiatric diagnoses and the use of various psychotropic medications.Methods: A cross-sectional observational study was conducted between July 2012 and June 2014. Patients were recruited from a number of hospitals located in the five regions of Saudi Arabia. Hyperprolactinemia was defined as blood prolactin levels >25?ng/mL in females and >20?ng/mL in males, regardless of the presence of symptoms.Results: A total of 997 patients (553 males and 444 females) were included in the current analysis. The average blood prolactin level was 32.6?±?44.1?ng/mL, with higher levels among females than males (42.9?±?61.3 versus 24.4?±?18.6, p?<?.001). The prevalence of hyperprolactinemia was 44.3%, with no significant gender difference (41.9% in females versus 46.3% in males, p?=?.164) but with huge variability according to individual antipsychotic and other psychotropic medications. In the multivariate analysis adjusted for demographic and clinical characteristics, hyperprolactinemia was independently and positively associated with using antipsychotic medications (OR?=?2.08, 1.26–3.42, p?=?.004). Additionally, previous hospitalisation, diabetes and hypothyroidism were positively associated, whereas having primary depressive disorders was negatively associated.Conclusions: We report a high prevalence of hyperprolactinemia among a large sample of psychiatric patients in Saudi Arabia, which was linked to the use of antipsychotic medications. Routine measurement of blood prolactin levels for all patients maintained on antipsychotic agents is recommended, regardless of symptoms. 相似文献
82.
In addition to their well-known genomic effects via intracellular receptors, androgens rapidly alter neuronal excitability through a nongenomic pathway. The nongenomic effect of testosterone, as the main androgen, apart from its traditional effects, was assessed in one of the fundamental centers of learning and memory, the hippocampus, on long-term memory (LTM) in passive avoidance conditioning. Different doses of testosterone enanthate (T) or testosterone-BSA (T-BSA) bilaterally were injected into the CA1 region of the hippocampus 15 min before shock delivery (1 mA during 5 s) in a two-compartment passive avoidance apparatus. After 24 h, animals were tested for passive avoidance retrieval. Bilateral injection of 20 microg T or 55 microg T-BSA into the CA1 significantly decreases step-through latency. Therefore, it seems that testosterone can impair LTM in passive avoidance conditioning both via intracellular receptors and through nongenomic pathway. 相似文献
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Shuzo Kitayama Peter Pilecki Nasser A. Nasser Theodora Bravis Ron F. Wilson Toru Nikaido Junji Tagami Timothy F. Watson Richard M. Foxton 《European journal of oral sciences》2009,117(4):454-462
This study investigated the effect of resin coating and occlusal loading on adhesion and microleakage of all-ceramic crowns. Molars were prepared for an all-ceramic crown and were divided into two groups: non-coated (control) and resin-coated with Clearfil Tri-S Bond. Crowns were fabricated using CEREC 3 and cemented using Clearfil Esthetic Cement. After 24 h of storage in water, the restored teeth in each group were divided into two subgroups: unloaded, or loaded while stored in water. Mechanical loading was achieved with an axial force of 80 N at 2.5 cycles s−1 for 250,000 cycles. After immersion in Rhodamine B, the specimens were sectioned and processed for microleakage evaluation by confocal microscopy, which was followed by further sectioning for microtensile bond testing. Loading had no significant effect on microleakage in either the resin-coated or non-resin-coated groups. Resin coating did not reduce the microleakage at the dentine interface but increased the microleakage at the enamel interface. All the beams fractured during slicing when non-coated and loaded. The bond strengths of non-coated and unloaded, resin-coated and unloaded, and resin-coated and loaded groups were 15.82 ± 4.22, 15.17 ± 5.24, and 12.97 ± 5.82 MPa, respectively. Resin coating with Clearfil Tri-S Bond improved the bonding of resin cement to dentine for loaded specimens. However, it was not effective in reducing the microleakage, regardless of whether it was loaded or unloaded. 相似文献
85.
Omar S. Al-Attas Nasser M. Al-Daghri Gamal A. Appiedu 《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2009,3(1):45-49
AimStudies have shown homocysteine to be an independent risk factor for atherosclerosis and CVD in both diabetic and non-diabetic subjects. However, the association between the levels of homocysteine and type 1 diabetes mellitus remains a controversial one. Our aim is to test this in a cross-section of the Saudi type 1 diabetics against non-diabetics to establish the relationship of homocysteine with regards to type 1 diabetics and non-diabetics.Materials and methodsA total of 97 subjects (41 males, 56 females) participated in this cross-sectional study done at the diabetic clinic of King Abdul-Aziz University Hospital Diabetic Centre, Riyadh, KSA. They were divided according to the presence of type 1 DM. Glycemic and lipid parameters were measured using routing procedures. Hcys was measured using photometric assay.ResultsAmong males, hcys levels were significantly lower among the diabetic subjects (p-value 0.03). Females with type 1 diabetes however have higher total cholesterol levels than their control counterparts (p-value 0.003). Among the control group, gender and HDL-cholesterol exhibited significant inverse relationships with hcys (p-values 0.028 and 0.032, respectively) and a strong positive association with body mass index (p-value 0.034). Among the diabetic group, only age was significantly associated with hcys (p-value 0.009).ConclusionIn the Arab population, hcys is decreased in IDDM subjects compared to non-diabetic subjects. Hcys was correlated to BMI and inversely associated to HDL-C among the non-diabetics. Further studies are needed to test the hypothesis in diabetics with disease complications. 相似文献
86.
Nasser Mikhail 《Current hypertension reports》2009,11(2):156-158
Insulin resistance is the most accepted unifying theory explaining the pathophysiology of the metabolic syndrome. However, epidemiologic studies indicate that a substantial proportion of patients with the metabolic syndrome do not have evidence of insulin resistance, and the correlation between insulin resistance and individual components of the syndrome is weak to moderate. Insulin resistance may play an important role in the development of hyperglycemia and dyslipidemia, which can further aggravate insulin resistance. The implication of insulin resistance in hypertension appears to be less strong than its role in causing hyperglycemia and dyslipidemia. Obesity may be another pathogenic factor in the metabolic syndrome that may help initiate or worsen insulin resistance. However, like insulin resistance, obesity is not universal in the metabolic syndrome, and many obese subjects do not have metabolic abnormalities. This review provides an update on the relationship between insulin resistance and main components of the metabolic syndrome: hyperglycemia, dyslipidemia, hypertension, and obesity. 相似文献
87.
Cannabis has been used to treat various afflictions throughout the centuries, including nausea, vomiting, and pain. It has also been used recreationally for its psychotropic properties, which can include a pleasurable ‘high’ feeling and a decrease in anxiety and tension; however, other may experience dysphoria. Changes in cognition and psychomotor performance are also well‐known with cannabis use. In recent years, our understanding of the endocannabinoid system (ECS) has progressed dramatically; the objective of identifying agents which may allow modulation of the ECS without significant psychotropic side effects may be possible. Inhibition of fatty acid amide hydrolase (FAAH), an important enzyme for the degradation of anandamide and other endogenous cannabinoids, is a promising target to achieve this goal. In this issue of Neurogastroenterology and Motility, Fichna and colleagues report on a novel selective FAAH inhibitor, PF‐3845, with potent antinociceptive and antidiarrheal effects in a mouse model. In this context, we briefly review the components of the ECS, discuss pharmacologic targets for indirect cannabinoid receptor stimulation, and describe recent research with cannabinoids for gut disorders. 相似文献
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89.
Cristoforo G. Gaetano Nasser Samadi Jose L. Tomsig Timothy L. Macdonald Kevin R. Lynch David N. Brindley 《Molecular carcinogenesis》2009,48(9):801-809
Increased expression of autotaxin in tumors including glioblastoma, breast, renal, ovarian, lung, and thyroid cancers is associated with increased tumor aggressiveness. Autotaxin promotes metastasis as well as cell growth, survival, and migration of cancer cells. These actions could depend on the noncatalytic effects of autotaxin on cell adhesion, or the catalytic activity of autotaxin, which converts lysophosphatidylcholine into lysophosphatidate in the extracellular fluid surrounding the tumor. Both lysophosphatidylcholine (LPC) and lysophosphatidate have been reported to stimulate migration through their respective G‐protein coupled receptors. The present study determines the roles of autotaxin, LPC, and lysophosphatidate in controlling the migration of two cancer cell lines: MDA‐MB‐231 breast cancer cells, which produce little autotaxin and MDA‐MB‐435 melanoma cells that secrete significant levels of autotaxin. LPC alone was unable to stimulate the migration of either cell type unless autotaxin was present. Knocking down autotaxin secretion, or inhibiting its catalytic activity, blocked cell migration by preventing lysophosphatidate production and the subsequent activation of LPA1/3 receptors. We conclude that inhibiting autotaxin production or activity could provide a beneficial adjuvant to chemotherapy for preventing tumor growth and metastasis in patients with high autotaxin expression in their tumors. © 2009 Wiley‐Liss, Inc. 相似文献
90.