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991.
Valproic acid is widely used in the treatment of behavioral disturbances in patients with dementia; however, there is uncertainty about its dosing and studies have reported mixed findings. The current article examines published trials of valproic acid in the treatment of patients with dementia to identify whether an optimal dosing strategy exists. Secondarily, valproic acid dosing from published studies is compared with a real-world 5-year sample of valproic acid prescribing. Twenty studies met selection criteria and were included in the review. Based primarily on uncontrolled trials and the current retrospective study, valproic acid serum levels between 40 and 60 mcg/mL and relatively low doses (ie, 7-12 mg/kg per d) are associated with improvements in agitation in some patients with dementia. At the same time, similar valproic acid levels produced no significant behavioral improvements in most placebo-controlled studies and led to substantial side effects in some patients. Considerable trial design differences exist between controlled and uncontrolled trials. Overall, valproic acid appears to have limited efficacy as monotherapy in many patients with dementia. Its optimal role may be in combination with other psychotropics as a treatment of agitation associated with dementia. 相似文献
992.
993.
Bujarski SJ Feldner MT Lewis SF Babson KA Trainor CD Leen-Feldner E Badour CL Bonn-Miller MO 《Addictive behaviors》2012,37(1):53-59
Contemporary comorbidity theory postulates that people suffering from posttraumatic stress symptoms may use substances to cope with negative affect generally and posttraumatic stress symptoms specifically. The present study involves the examination of the unique relation between past two-week posttraumatic stress symptom frequency and motives for marijuana use after accounting for general levels of negative affectivity as well as variability associated with gender. Participants were 61 marijuana-using adolescents (Mage = 15.81) who reported experiencing lifetime exposure to at least one traumatic event. Consistent with predictions, past two-week posttraumatic stress symptoms significantly predicted coping motives for marijuana use and were not associated with social, enhancement, or conformity motives for use. These findings are consistent with theoretical work suggesting people suffering from posttraumatic stress use substances to regulate symptoms. 相似文献
994.
Brien KA Bandi RK Behera AK Mishra BK Majumdar P Satam V Savagian M Tzou S Lee M Zeller M Robles AJ Mooberry S Pati H Lee M 《Archiv der Pharmazie》2012,345(5):341-348
Two divergent series of novel chalcone analogs, one derived from 1‐cyclohexylpyrrolidin‐2‐one and the other derived from 1‐benzo[f]chromanone, were designed, synthesized and evaluated for cytotoxicity against two murine cancer cell lines. Two 1‐benzo[f]chromanone analogs, 4g and 4j yielded moderate toxicity against both melanoma B16 and lymphoma L1210 cell lines with IC50 values between the range of 5 and 6 µM. With an IC50 value of 3.4 µM, compound 4g was also active against human MDA‐MB‐435 melanoma cells. X‐ray structures of the β‐hydroxy ketone product ( 4a ) and the α,β‐unsaturated ketone ( 4h ) were collected, and confirm the syn‐configuration between the carbonyl moiety and the β‐vinylic proton in 4h . X‐ray structures of two 1‐cyclohexylpyrrolidin‐2‐one derivatives were also obtained, and both showed an E‐configuration for the double bond. 相似文献
995.
Poly(β-amino ester) (PBAE) biodegradable hydrogels were investigated for potential combined chemotherapeutic and heat delivery in the synergistic treatment of cancer. Hyperthermia, the heating of cancerous tissue from 41 to 45 °C, increases the efficacy of conventional cancer therapies such as irradiation and chemotherapy. The hydrogel nanocomposites in this work provide a drug delivery vehicle (via the biodegradable PBAE polymer network) and the ability to be heated remotely upon exposure to an alternating magnetic field (via iron oxide nanoparticles incorporated into the hydrogel matrix). PBAE macromers composed of poly(ethylene glycol) (N=400) diacrylate (PEG400DA) or diethylene glycol diacrylate (DEGDA) with isobutylamine (IBA) were synthesized. Hydrogel nanocomposites were fabricated via free-radical polymerization to form a bulk hydrogel matrix entrapping both iron oxide nanoparticles and paclitaxel. The 2EG-IBA hydrogel exhibited complete degradation after approximately 7 weeks whereas the 9EG-IBA hydrogel degraded completely in 11h. The hydrogels heated upon exposure to an alternating magnetic field throughout the degradation process. Additionally, the cytotoxicity of the degradation products was evaluated. Paclitaxel release was controlled via bulk degradation of the hydrogels. The tailorability of these nanocomposites makes them solid candidates for the synergistic treatment of cancer. 相似文献
996.
We previously described a lipid-accumulating phenotype of estrogen receptor negative (ER−) breast cancer cells exemplified by the MDA-MB-231 and MDA-MB-436 cell lines. These cells had more lipid droplets, a higher
uptake of oleic acid and LDL, a higher ratio of cholesteryl ester (CE) to triacylglycerol (TAG), and higher expression of
acyl-CoA:cholesterol acyltransferase 1 (ACAT1) as compared to ER+ MCF-7 breast cancer cells. LDL stimulated proliferation of ER-cells only, and proliferation was reduced by inhibition of
ACAT. We hypothesized that storage of exogenous lipids would confer an energetic advantage. We tested this by depriving cells
of exogenous lipids and measuring chemotactic migration, an energy-intensive behavior. MDA-MB-231 cells were grown for 48 h
in medium with either 5% FBS or 5% lipoprotein-depleted (LD) FBS. Growth in LD medium resulted in visibly reduced lipid droplets
and an 85% decrease in cell migration. Addition of LDL to the LD medium dose-dependently restored the ability to migrate in
an ACAT-sensitive manner. LDL receptor (LDLR) mRNA was 12-fold higher in MDA-MB-231 cells compared to nontumorigenic ER-MCF-10A
breast epithelial cells grown in LD medium. Addition of LDL to the LD medium reduced LDLR mRNA levels in MCF-10A cells only.
We asked if ACAT1 activity was associated with the expression of the LDLR in MDA-MB-231 cells. LDLR mRNA in MDA-MB-231 cells
was substantially reduced by inhibition of ACAT, demonstrating that high ACAT1 activity permitted higher LDLR expression.
This data substantiates the association of lipid accumulation with aggressive behavior in an ER-breast cancer cell line. 相似文献
997.
Erik J. Groessl Kimberly R. WeingartAllen L. Gifford Steven M. Asch Samuel B. Ho 《Patient education and counseling》2011,83(2):252-255
Objective
Chronic hepatitis C infection (HCV) is a major health problem that disproportionately affects people with limited resources. Many people with HCV are ineligible or refuse antiviral treatment, but less curative treatment options exist. These options include adhering to follow-up health visits, lifestyle changes, and avoiding hepatotoxins like alcohol. Herein, we describe a recently developed self-management program designed to assist HCV-infected patients with adherence and improve their health-related quality of life (HRQOL).Methods
The development of the Hepatitis C Self-Management Program (HCV-SMP) was informed by scientific literature, qualitative interviews with HCV-infected patients, self-management training, and feedback from HCV clinical experts.Results
The Hepatitis C Self-Management Program (HCV-SMP) is a multi-faceted program that employs cognitive-behavioral principles and is designed to provide HCV-infected people with knowledge and skills for improving their HRQOL. The program consists of six 2-h workshop sessions which are held weekly. The sessions consist of a variety of group activities, including disease-specific information dissemination, action planning, and problem-solving.Conclusion
The intervention teaches skills for adhering to challenging treatment recommendations using a validated theoretical model. A randomized trial will test the efficacy of this novel HCV self-management program for improving HRQOL in a difficult to reach population. 相似文献998.
999.
The serotonin (5HT) system of the brain is involved in many CNS functions including sensory perception, stress responses and psychological disorders such as anxiety and depression. Of the nine 5HT nuclei located in the mammalian brain, the dorsal raphe nucleus (DRN) has the most extensive forebrain connectivity and is implicated in the manifestation of stress-related psychological disturbances. Initial investigations of DRN efferent connections failed to acknowledge the rostrocaudal and mediolateral organization of the nucleus or its neurochemical heterogeneity. More recent studies have focused on the non-5HT contingent of DRN cells and have revealed an intrinsic intranuclear organization of the DRN which has specific implications for sensory signal processing and stress responses. Of particular interest are spatially segregated subsets of nitric oxide producing neurons that are activated by stressors and that have unique efferent projection fields. In this regard, both the midline and lateral wing subregions of the DRN have emerged as prominent loci for future investigation of nitric oxide function and modulation of sensory- and stressor-related signals in the DRN and coinciding terminal fields. 相似文献
1000.