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61.
Problems with measuring peripheral oxytocin: Can the data on oxytocin and human behavior be trusted?
Michael E. McCullough Patricia Smith Churchland Armando J. Mendez 《Neuroscience and biobehavioral reviews》2013
Research on the neurobiological and behavioral effects of oxytocin (OT), as well as on its possible therapeutic applications, has intensified in the past decade. Accurate determination of peripheral OT levels is essential to reach meaningful conclusions and to motivate, support and inform clinical interventions. Different, but concordant, methods for measuring plasma OT have been developed over the past four decades, but since 2004 several commercially available methods have been favored in research with humans. Evaluation of these methods reveals that they lack reliability when used on unextracted samples of human fluids, and that they tag molecules in addition to OT, yielding estimates that are wildly discrepant with an extensive body of earlier findings that were obtained using methods that are well validated, but more laborious. An accurate, specific, and readily available method for measuring OT that can be adopted as the standard in the field is urgently needed for advances in our understanding of OT's roles in cognition and behavior. 相似文献
62.
C. Ellie Wilson Nicola Gillan Deborah Spain Dene Robertson Gedeon Roberts Clodagh M. Murphy Stefanos Maltezos Janneke Zinkstok Katie Johnston Christina Dardani Chris Ohlsen P. Quinton Deeley Michael Craig Maria A. Mendez Francesca Happé Declan G. M. Murphy 《Journal of autism and developmental disorders》2013,43(11):2515-2525
An Autism Spectrum Disorder (ASD) diagnosis is often used to access services. We investigated whether ASD diagnostic outcome varied when DSM-5 was used compared to ICD-10R and DSM-IV-TR in a clinical sample of 150 intellectually able adults. Of those diagnosed with an ASD using ICD-10R, 56 % met DSM-5 ASD criteria. A further 19 % met DSM-5 (draft) criteria for Social Communication Disorder. Of those diagnosed with Autistic Disorder/Asperger Syndrome on DSM-IV-TR, 78 % met DSM-5 ASD criteria. Sensitivity of DSM-5 was significantly increased by reducing the number of criteria required for a DSM-5 diagnosis, or by rating ‘uncertain’ criteria as ‘present’, without sacrificing specificity. Reduced rates of ASD diagnosis may mean some ASD individuals will be unable to access clinical services. 相似文献
63.
Diana A. Chirinos Ronald B. Goldberg Maria M. Llabre Marc Gellman Miriam Gutt Judith McCalla Armando Mendez Neil Schneiderman 《Journal of behavioral medicine》2016,39(3):483-492
Although weight is an important intervention target among patients with metabolic syndrome, few trials have recruited low-income minority populations. The Community Health and Risk-reduction for Metabolic Syndrome randomized controlled trial aimed to examine the effects of a lifestyle intervention on weight and metabolic syndrome components among low-income minority adults. We randomized 120 adults with metabolic syndrome to standard medical care (N = 60) or a lifestyle intervention (N = 60). Using an intent-to-treat approach, we found significant intervention effects on weight [B = ?0.452; SE = 0.122; 95 % confidence intervals (CI) ?0.653 to ?0.251) and glucose levels at 6-months (B = ?0.522, SE = 0.234, 95 % CI ?0.907 to ?0.138). These changes were maintained through the 12-month assessment. No significant effects were observed on insulin resistance or other metabolic syndrome components. Our intervention was successful in achieving modest but significant weight loss and reduction in fasting glucose among low-income minority subjects with metabolic syndrome. 相似文献
64.
OBJECTIVE: We assessed a new estradiol (E2) immunoassay on the Architect-i2000 (Abbott Laboratories) for monitoring ovulation stimulation for IVF-ET and re-establishing clinical cut-off points. The method has been modified to improve E2 measurements especially at normal and low concentrations. DESIGN AND METHOD: E2 was determined for 552 samples, from 83 women, presenting normal follicular status and undergoing 100 cycles of IVF treatment. We assessed the value of this assay for down-regulation of E2 concentration limit using gonadoliberin-releasing hormone agonist (GnRHa), and monitoring of the ovarian hyperstimulation, expected range of E2 per mature follicle prior to the administration of exogenous hCG and day 3 concentration limit. We compared results with our routine method (E2-6II Advia-Centaur; Siemens-Diagnostics) for which decision-making values were known. RESULTS: Considering E2 concentrations obtained with the new Architect-i2000 assay for patients treated with GnRHa for 2 weeks, the cutoff-point for ovarian down-regulation should be set down at 110 pmol/L to maintain 100% of sensitivity. Considering day 3 concentration limit determination, results were not significantly different from those obtained with our routine method. The mean E2 values per mature follicle fell into the range generally expected. CONCLUSION: E2 determination with the new E2 Architect-i2000 assay could be used to monitor ovulation, in patients undergoing IVF-ET, in combination with transvaginal ultrasound. 相似文献
65.
Diego Nunez Jr. MD Jorge J. Guerra Jr. Wajih A. Al-Sheikh Edward Russell Gaston Mendez Jr. 《Abdominal imaging》1986,11(1):85-89
One hundred and sixteen percutaneous drainage procedures of the biliary system were performed in a 2-year period. Eight of 9 acutely ill patients with the diagnosis of acute suppurative cholangitis were successfully treated nonoperatively. They represented 26% of all patients with benign or postsurgical obstruction referred for biliary decompression. Conversely, acute suppurative cholangitis only occurred in 2.3% of patients with underlying malignant disease. These observations are considered most relevant in predicting the purulent nature of the disease, with further implications for patient management. Early recognition and prompt decompression of the biliary system are mandatory, along with the appropriate antibiotic coverage. Our experience compares favorably with surgical results and the procedure is proposed as the method of choice for the initial treatment of acute suppurative cholangitis. 相似文献
66.
Edilma?MV?Albuquerque Eliana?C?de Faria Helena?CF?Oliveira Daniela?O?Magro Lucia?N?CastilhoEmail author 《BMC infectious diseases》2005,5(1):47
Background
Human immunodeficiency virus (HIV) infection is very prevalent in Brazil. HIV therapy has been recently associated with coronary heart disease (CHD). Dyslipidemia is a major risk factor for CHD that is frequently described in HIV positive patients, but very few studies have been conducted in Brazilian patients evaluating their lipid profiles. 相似文献67.
Role of guanylate cyclase-activating proteins (GCAPs) in setting the flash sensitivity of rod photoreceptors 总被引:3,自引:0,他引:3
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Mendez A Burns ME Sokal I Dizhoor AM Baehr W Palczewski K Baylor DA Chen J 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(17):9948-9953
The retina's photoreceptor cells adjust their sensitivity to allow photons to be transduced over a wide range of light intensities. One mechanism thought to participate in sensitivity adjustments is Ca(2+) regulation of guanylate cyclase (GC) by guanylate cyclase-activating proteins (GCAPs). We evaluated the contribution of GCAPs to sensitivity regulation in rods by disrupting their expression in transgenic mice. The GC activity from GCAPs-/- retinas showed no Ca(2+) dependence, indicating that Ca(2+) regulation of GCs had indeed been abolished. Flash responses from dark-adapted GCAPs-/- rods were larger and slower than responses from wild-type rods. In addition, the incremental flash sensitivity of GCAPs-/- rods failed to be maintained at wild-type levels in bright steady light. GCAP2 expressed in GCAPs-/- rods restored maximal light-induced GC activity but did not restore normal flash response kinetics. We conclude that GCAPs strongly regulate GC activity in mouse rods, decreasing the flash sensitivity in darkness and increasing the incremental flash sensitivity in bright steady light, thereby extending the rod's operating range. 相似文献
68.
Hematologic and immunomodulatory effects of an interleukin-1 receptor antagonist coinfusion during low-dose endotoxemia in healthy humans 总被引:3,自引:0,他引:3
Granowitz EV; Porat R; Mier JW; Orencole SF; Callahan MV; Cannon JG; Lynch EA; Ye K; Poutsiaka DD; Vannier E 《Blood》1993,82(10):2985-2990
Endotoxin is a component of gram-negative bacteria that causes hematologic and immunologic changes through its induction of cytokines. Interleukin-1 receptor antagonist (IL-1Ra) is a naturally occurring inhibitor of IL-1 that competes with IL-1 for occupancy of cell-surface receptors but possesses no agonist activity. We investigated the ability of human recombinant IL-1Ra to block the effects of low-dose endotoxin. Fourteen healthy male volunteers between 18 and 30 years old were injected intravenously with 3 ng/kg Escherichia coli endotoxin. Concurrent with the injections, nine volunteers received a 3-hour continuous intravenous infusion of IL-1Ra. The other five subjects were given a 3-hour infusion of saline. Volunteers injected with endotoxin experienced a threefold increase in circulating neutrophils over baseline. This neutrophilia was significantly reduced by 48% in subjects administered endotoxin plus IL-1Ra (P = .0253). Ex vivo mitogen-induced peripheral blood mononuclear cell proliferation decreased by greater than 60% at 3 and 6 hours after endotoxin injection (P = .0053). This endotoxin-induced reduction in mitogen response was reversed in subjects coinjected with IL-1Ra (P = .0253). Endotoxin-induced symptoms, fever, and tachycardia were unaffected by IL-1Ra. IL-1 appears to be an important mediator in endotoxemia because some of its hematologic and immunomodulatory effects can be blocked by IL-1Ra. 相似文献
69.
Etoposide is one of the most widely used antineoplastics. Unfortunately, the same treatment schedules associated with impressive efficacy are associated with an increased risk of secondary acute myeloid leukemia (AML), which has prompted its withdrawal from some treatment regimens, thereby potentially compromising efficacy against the original tumor. Because etoposide-associated AML is characterized by site-specific illegitimate DNA recombination, we studied whether etoposide could directly cause site-specific deletions of exons 2 and 3 in the hprt gene. Human lymphoid CCRF-CEM cells were treated with etoposide for 4 hours, and DNA was isolated after subculturing. The deletion of exons 2 and 3 from hprt was assayed by a quantitative polymerase chain reaction (PCR) method. In the absence of etoposide treatment, the frequency of deletions of exons 2 and 3 was very low (5.05 x 10(-8)). After exposure to 10 mumol/ L etoposide, the frequency of the exon 2 + 3 deletion was increased immediately after and at 24 hours after etoposide treatment (65 to 89 x 10(-8)) and increased to higher levels (128 to 173 x 10(-8)) after 2 and 6 days of subculture (P < .001 overall). The frequency of the exon 2 + 3 deletion assessed at 6 days of subculture after 4 hours of 0, 0.25, 1, 2.5, 5, and 10 mumol/L etoposide treatment increased with etoposide concentration, ie, 5.05 x 10(-8), 89.2 x 10(-8), 108 x 10(-8), 142 x 10(-8), 163 x 10(-8), and 173 x 10(-8), respectively (P < .0001). Sequencing of a subset of amplified products confirmed the presence of DNA sequences at the breakpoints consistent with V(D)J recombination. By contrast, exon 2 + 3 deletions after etoposide treatment in the myeloid cell lines KG-1A and K562 showed no evidence of V(D)J recombinase in their genesis. We conclude that etoposide can induce the illegitimate site-specific action of V(D)J recombinase on an unnatural DNA substrate after a single treatment in human lymphoid cells. 相似文献
70.
Munirul Alam Shah Manzur Rashed Shahnewaj Bin Mannan Tarequl Islam Marcial Leonardo Lizarraga-Partida Gabriela Delgado Rosario Morales-Espinosa Jose Luis Mendez Armando Navarro Haruo Watanabe Makoto Ohnishi Nur A. Hasan Anwar Huq R. Bradley Sack Rita R. Colwell Alejandro Cravioto 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(27):9917-9922