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61.
Litten RZ Fertig JB Falk DE Ryan ML Mattson ME Collins JF Murtaugh C Ciraulo D Green AI Johnson B Pettinati H Swift R Afshar M Brunette MF Tiouririne NA Kampman K Stout R;NCIG Study Group 《Alcoholism, clinical and experimental research》2012,36(3):406-416
Background: Despite advances in developing medications to treat alcohol dependence, few such medications have been approved by the Food and Drug Administration. Identified molecular targets are encouraging and can lead to the development and testing of new compounds. Atypical antipsychotic medications have been explored with varying results. Prior research suggests that the antipsychotic quetiapine may be beneficial in an alcohol‐dependent population of very heavy drinkers. Methods: In this double‐blind, placebo‐controlled trial, 224 alcohol‐dependent patients who reported very heavy drinking were recruited across 5 clinical sites. Patients received either quetiapine or placebo and Medical Management behavioral intervention. Patients were stratified on gender, clinical site, and reduction in drinking prior to randomization. Results: No differences between the quetiapine and placebo groups were detected in the primary outcome, percentage heavy‐drinking days, or other drinking outcomes. Quetiapine significantly reduced depressive symptoms and improved sleep but had no effect on other nondrinking outcomes. Results from a subgroup analysis suggest that patients who reduced their drinking prior to randomization had significantly better drinking outcomes during the maintenance phase (p < 0.0001). No significant interactions, however, were observed between reducer status and treatment group. Finally, quetiapine was generally well tolerated. Statistically significant adverse events that were more common with quetiapine versus placebo include dizziness (14 vs. 4%), dry mouth (32 vs. 9%), dyspepsia (13 vs. 2%), increased appetite (11 vs. 1%), sedation (15 vs. 3%), and somnolence (34 vs. 9%). Conclusions: This multisite clinical trial showed no efficacy for quetiapine compared with placebo at reducing alcohol consumption in heavy‐drinking alcohol‐dependent patients. 相似文献
62.
For many patients with end-stage heart failure, heart transplantation is the only remaining option to prolong survival and provide symptom relief. Transthoracic echo is the modality of choice in assessing a patient for potential left ventricular assist device (LVAD) insertion. There are currently no guidelines available, and assessing this specific patient population can prove extremely challenging. As such, an understanding of LVAD mechanism, the important physiological consequences of device implantation together with the related echocardiographic examination is vital to accurately and effectively gauge correct patient selection and also improve implantation success. This review aims to highlight the common devices implanted, how these devices affect cardiac physiology and hemodynamics, and therefore discuss the major echocardiographic variables that should be assessed predevice implantation. (Echocardiography 2012;29:52-58). 相似文献
63.
Mascari TM Stout RW Foil LD 《Vector borne and zoonotic diseases (Larchmont, N.Y.)》2012,12(8):699-704
The purpose of this study was to evaluate the efficacy of oral treatment of rodents with diets containing the systemic insecticides ivermectin, abamectin, imidacloprid, or spinosad, to control bloodfeeding sand flies. We found that diets containing concentrations higher than 10 mg/kg abamectin were not palatable to rodents, and that a diet containing 10 mg/kg abamectin (a palatable concentration) did not cause 100% mortality of bloodfeeding sand flies. Treatment of rodents with imidacloprid was effective for less than 3 days post-treatment. Treatment of rodents with diets containing 20 mg/kg ivermectin or 5000 mg/kg spinosad caused 100% mortality of bloodfeeding sand flies for at least 1 week. The efficacy of ivermectin and spinosad also were not reduced when combined with the fluorescent tracer dye rhodamine B in a single diet. We also did not observe significant benefits by increasing the feeding period of the rodents from 3 to 6 or 9 days. We conclude that ivermectin and spinosad are effective as rodent systemic insecticides against bloodfeeding sand flies, and suggest that weekly treatment of wild rodent reservoirs of Leishmania major with bait containing one of these systemic insecticides could be a useful tool as part of a sand fly control program. 相似文献
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65.
Rachael I. Scahill Nicola Z. Hobbs Miranda J. Say Natalie Bechtel Susie M.D. Henley Harpreet Hyare Douglas R. Langbehn Rebecca Jones Blair R. Leavitt Raymund A.C. Roos Alexandra Durr Hans Johnson Stéphane Lehéricy David Craufurd Christopher Kennard Stephen L. Hicks Julie C. Stout Ralf Reilmann Sarah J. Tabrizi the TRACK‐HD investigators 《Human brain mapping》2013,34(3):519-529
TRACK‐HD is a multicentre longitudinal observational study investigating the use of clinical assessments and 3‐Tesla magnetic resonance imaging as potential biomarkers for future therapeutic trials in Huntington's disease (HD). The cross‐sectional data from this large well‐characterized dataset provide the opportunity to improve our knowledge of how the underlying neuropathology of HD may contribute to the clinical manifestations of the disease across the spectrum of premanifest (PreHD) and early HD. Two hundred and thirty nine gene‐positive subjects (120 PreHD and 119 early HD) from the TRACK‐HD study were included. Using voxel‐based morphometry (VBM), grey and white matter volumes were correlated with performance in four domains: quantitative motor (tongue force, metronome tapping, and gait); oculomotor [anti‐saccade error rate (ASE)]; cognition (negative emotion recognition, spot the change and the University of Pennsylvania smell identification test) and neuropsychiatric measures (apathy, affect and irritability). After adjusting for estimated disease severity, regionally specific associations between structural loss and task performance were found (familywise error corrected, P < 0.05); impairment in tongue force, metronome tapping and ASE were all associated with striatal loss. Additionally, tongue force deficits and ASE were associated with volume reduction in the occipital lobe. Impaired recognition of negative emotions was associated with volumetric reductions in the precuneus and cuneus. Our study reveals specific associations between atrophy and decline in a range of clinical modalities, demonstrating the utility of VBM correlation analysis for investigating these relationships in HD. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc. 相似文献
66.
Donglei Wei Jinsuh Jung Huilin Yang David A. Stout Lei Yang 《Current osteoporosis reports》2016,14(5):239-247
Unfortunately, osteoporosis, as a worldwide disease, is challenging human health with treatment only available for the symptoms of osteoporosis without managing the disease itself. Osteoporosis can be linked as the common cause of fractures and increased mortality among post-menopausal women, men, and the elderly. Regrettably, due to osteoporosis, incidents of fractures are more frequent among the presented populations and can be afflictive for carrying out everyday life activities. Current treatments of osteoporosis encompass changing lifestyles, taking orthopedic drugs, and invasive surgeries. However, these treatment options are not long lasting and can lead to complications after post-surgical life. Therefore, to solve this impairment, researchers have turned to nanotechnologies and nanomaterials to create innovative and alternative treatments associated with the consequences of osteoporosis. This review article provides an introduction to osteoporotic compression vertebral fractures (OVCFs) and current clinical treatments, along with the rationale and efficacy of utilizing nanomaterials to modify and improve biomaterials or instruments. The methods of applying bioactive agents (bone morphogenetic protein-2 (BMP-2), parathyroid hormone 1–34 (PTH 1–34)), as well as 3D printing will be presented from an osteoporosis treatment perspective. Additionally, the application of nanoparticles and nanotube arrays onto the current surgical treatments and orthopedic drug administration methods addressed will show that these systems reinforce a better mechanical performance and provide precise and slow-releasing drug delivery for better osseointegration, bone regeneration, and bone strength. In summary, nanomaterials can be seen as an alternative and more effective treatment for individuals with osteoporosis. 相似文献
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68.
O'Malley CJ; Rasko JE; Basser RL; McGrath KM; Cebon J; Grigg AP; Hopkins W; Cohen B; O'Byrne J; Green MD; Fox RM; Berndt MC; Begley CG 《Blood》1996,88(9):3288-3298
This report describes the effect of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) on platelet production and platelet function in humans. Subjects with advanced solid tumors received PEG-rHuMGDF daily for up to 10 days. There was no increase in circulating platelet count at doses of 0.03 or 0.1 microgram/kg/d by day 12 of study. At doses of 0.3 and 1.0 microgram/kg/d there was a threefold median increase (maximum 10-fold) in platelet count by day 16. The platelets produced in vivo in response to PEG-rHuMGDF showed unchanged aggregation and adenosine triphosphate (ATP)-release responses in in vitro assays. Tests included aggregation and release of ATP in response to adenosine diphosphate (ADP) (10, 5, 2.5, and 1.25 mumol/L), collagen (2 micrograms/mL), thrombin-receptor agonist peptide (TRAP, 10 mumol/L) and ristocetin (1.5 mg/mL). Administration of aspirin to an individual with platelet count of 1,771 x 10(3)/L resulted in the typical aspirin-induced ablation of the normal aggregation and ATP-release response to stimulation with arachidonic acid (0.5 mg/mL), collagen, and ADP (2.5 and 1.25 mumol/L). There was no change in the expression of the platelet-surface activation marker CD62P (P-selectin) nor induction of the fibrinogen binding site on glycoprotein IIb/IIIa as reported by the monoclonal antibody, D3GP3. An elevation of reticulated platelets was evident after 3 days of treatment with PEG-rHuMGDF and preceded the increase in circulating platelet count by 5 to 8 days; this reflected the production of new platelets in response to PEG-rHuMGDF. At later time points, the mean platelet volume (MPV) decreased in a manner inversely proportional to the platelet count. Levels of plasma glycocalicin, a measure of platelet turnover, rose 3 days after the initial increase in the peripheral platelet count. The level of plasma glycocalicin was proportional to the total platelet mass, suggesting that platelets generated in response to PEG-rHuMGDF were not more actively destroyed. Thus, the administration of PEG-rHuMGDF, to humans, increased the circulating platelet count and resulted in fully functional platelets, which showed no detectable increase in reactivity nor alteration in activation status. 相似文献
69.
[4Fe-4S]-cluster-depleted Azotobacter vinelandii ferredoxin I: a new 3Fe iron-sulfur protein. 总被引:1,自引:0,他引:1 下载免费PDF全文
P J Stephens T V Morgan F Devlin J E Penner-Hahn K O Hodgson R A Scott C D Stout B K Burgess 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(17):5661-5665
Fe(CN)6(-3) oxidation of the aerobically isolated 7Fe Azotobacter vinelandii ferredoxin I, (7Fe)FdI, is a degradative reaction. Destruction of the [4Fe-4S] cluster occurs first, followed by destruction of the [3Fe-3S] cluster. At a Fe(CN)6(-3)/(7Fe)FdI concentration ratio of 20, the product is a mixture of apoprotein and protein containing only a [3Fe-3S] cluster, (3Fe)FdI. This protein mixture, after partial purification, has been characterized by absorption, CD, magnetic CD, and EPR and Fe x-ray absorption spectroscopies. EPR and magnetic CD spectra provide strong evidence that the [3Fe-3S] cluster in (3Fe)FdI is essentially identical in structure to that in (7Fe)FdI. Analysis of the extended x-ray absorption fine structure (EXAFS) of (3Fe)FdI finds Fe scattering at an average Fe...Fe distance of approximately equal to 2.7 A. The structure of the oxidized [3Fe-3S] cluster in solutions of oxidized (3Fe)FdI, and, by extension, of oxidized (7Fe)FdI, is thus different from that obtained by x-ray crystallography on oxidized (7Fe)FdI. Possible interpretations of this result are discussed. 相似文献
70.
New Zealand Black (NZB) autoimmune mice exhibit progressive, age- dependent reduction in bone marrow pre-B cells. To ascertain the capacity of NZB bone marrow B220- cells to generate pre-B cells in a supportive environment, B-lineage (B220+) cell-depleted and T-cell- depleted bone marrow cells from NZB mice at 1 to 3, 6, and 10 to 11 months of age were adoptively transferred into irradiated (200R) C.B17 severe combined immunodeficient (SCID) mice. Bone marrow pre-B cells (sIgM- CD43[S7]- B220+) were assessed 3 and 10 weeks posttransfer. Pre- B cells and B cells were reconstituted in SCID recipients of older NZB progenitor cells by 10 weeks posttransplant, in contrast to the very low numbers of pre-B cells present in the donor bone marrow. However, B220- bone marrow progenitor cells from greater than 10-month-old NZB donors were deficient in the reconstitution of both pre-B and B cells in SCID recipients at 3 weeks post-transfer. This reflected a slower kinetics of repopulation, because older NZB-->SCID recipients had numbers of both pre-B and B cells similar to recipients of young NZB progenitor cells by 10 weeks posttransplant. Adoptive transfer of equal mixtures of BALB/c and older NZB bone marrow B220- progenitor cells into irradiated C.B17 SCID recipients failed to demonstrate active suppression. These results suggest that, with age, NZB bone marrow has reduced numbers and/or function of early B220- B-lineage progenitors. Consistent with this hypothesis, B220- bone marrow cells from older NZB mice were deficient in progenitors capable of yielding interleukin-7 (IL-7) responsive pre-B cells in vitro on stimulation with the pre-B- cell potentiating factor, insulin-like growth factor 1 (IGF-1). 相似文献