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991.
Federica Benvenuti Nazzareno Cannella Serena Stopponi Laura Soverchia Massimo Ubaldi Veronica Lunerti Valentina Vozella Bryan Cruz Marisa Roberto Roberto Ciccocioppo 《International journal of molecular sciences》2021,22(8)
Alcoholism is a chronically relapsing disorder characterized by high alcohol intake and a negative emotional state during abstinence, which contributes to excessive drinking and susceptibility to relapse. Stress, dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and alterations in glucocorticoid receptor (GR) function have been linked to transition from recreational consumption to alcohol use disorder (AUD). Here, we investigated the effect of pharmacological antagonisms of GR on alcohol self-administration (SA) using male and female Wistar and Marchigian Sardinian alcohol-preferring (msP) rats, a rodent line genetically selected for excessive alcohol drinking and highly sensitive to stress. Animals were trained to self-administer 10% (v/v) alcohol. Once a stable alcohol SA baseline was reached, we tested the effect of the GR antagonists mifepristone (0.0, 10, 30 and 60 mg/kg; i.p.) and CORT113176 (0.0, 10, 30 and 60 mg/kg) on alcohol SA. To evaluate whether the effects of the two compounds were specific for alcohol, the two drugs were tested on a similar saccharin SA regimen. Finally, basal blood corticosterone (CORT) levels before and after alcohol SA were determined. Systemic injection with mifepristone dose-dependently reduced alcohol SA in male and female Wistars but not in msPs. Administration of CORT113176 decreased alcohol SA in male and female Wistars as well as in female msPs but not in male msP rats. At the highest dose, mifepristone also reduced saccharin SA in male Wistars and female msPs, suggesting the occurrence of some nonspecific effects at 60 mg/kg of the drug. Similarly, the highest dose of CORT113176 (60 mg/kg) decreased saccharin intake in male Wistars. Analysis of CORT levels revealed that females of both rat lines had higher blood levels of CORT compared to males. Alcohol consumption reduced CORT in females but not in males. Overall, these findings indicate that selective blockade of GR selectively reduces alcohol SA, and genetically selected msP rats are less sensitive to this pharmacological manipulation compared to heterogeneous Wistars. Moreover, results suggest sex differences in response to GR antagonism and the ability of alcohol to regulate GR transmission. 相似文献
992.
A Beyer-Mears FP Diecke K Mistry C Ellison E Cruz 《Canadian Metallurgical Quarterly》1997,55(2):78-86
Attitudes toward deviant behavior that might indicate psychiatric disorder were investigated among the Inuit of Northern Québec (Nunavik). In a convenience sample of 137 Inuit adults, respondents were randomly presented with one of six different vignettes that described a man with "strange" behavior who was either threatening or withdrawn and whose problem was labeled either "isumaluttuq" ("burdened or weighed down by thoughts"), "demon possession," or "mental illness." Respondents rated their willingness to live, work, or hunt with this person and allow him into their family on a social distance scale. Significant predictors of greater social distance were female gender, more education, less familiarity with the behavior, and perception of the person as less likely to recover. There were no significant effects of vignette behavior or label on social distance ratings. Rating of likelihood of recovery was influenced by the vignette label, with isumaluttuq associated with less chance of recovery. Ascribing strange behavior to morally wrong action and to spirits or demons were highly inter-correlated and each was associated with perception of greater likelihood of recovery. Results suggest that Inuit attitudes toward deviant behavior are influenced more by perceived familiarity and likelihood of recovery than by labels, causal attributions, or explanations. The indigenous psychological concept of isumaluttuq does not serve to reduce social stigma. Efforts to promote the community integration of psychiatric patients through education should aim to increase familiarity with the problematic behavior and emphasize potential for recovery. 相似文献
993.
The scheelite-type compounds have been investigated due to their interesting properties of photoluminescence and recently, they have been applied as photocatalysts in air and water purification trough the removal of different organic and inorganic pollutants. In this work, four scheelite-type ABO4 (A = Ca, Pb; B = W, Mo) compounds were prepared by co-precipitation method and its capacity to act as photocatalyst was evaluated in the removal of NOx gases using the oxidation of nitric oxide (NO) as model reaction. The photocatalytic activity of the samples decreased in the following order: CaMoO4 > PbWO4 > PbMoO4 > CaWO4, which was related with the electronic properties associated with each sample. When the photocatalyst with the highest photocatalytic activity (CaMoO4) was activated under UV radiation, the selectivity for the formation of NO3? ions was 35%, revealing the ability of the photocatalyst to carry out a deep oxidation of NO until innocuous products. Based in the modification of the experimental conditions, the mechanism proposed for the photooxidation of NO to NO3? ions was mainly by the action of the ion superoxide (O2?) formed from the O2 adsorbed on CaMoO4 surface. 相似文献
994.
Alina Kirillova Ridge Maxson Georgi Stoychev Cheryl T. Gomillion Leonid Ionov 《Advanced materials (Deerfield Beach, Fla.)》2017,29(46)
Despite the tremendous potential of bioprinting techniques toward the fabrication of highly complex biological structures and the flourishing progress in 3D bioprinting, the most critical challenge of the current approaches is the printing of hollow tubular structures. In this work, an advanced 4D biofabrication approach, based on printing of shape‐morphing biopolymer hydrogels, is developed for the fabrication of hollow self‐folding tubes with unprecedented control over their diameters and architectures at high resolution. The versatility of the approach is demonstrated by employing two different biopolymers (alginate and hyaluronic acid) and mouse bone marrow stromal cells. Harnessing the printing and postprinting parameters allows attaining average internal tube diameters as low as 20 µm, which is not yet achievable by other existing bioprinting/biofabrication approaches and is comparable to the diameters of the smallest blood vessels. The proposed 4D biofabrication process does not pose any negative effect on the viability of the printed cells, and the self‐folded hydrogel‐based tubes support cell survival for at least 7 d without any decrease in cell viability. Consequently, the presented 4D biofabrication strategy allows the production of dynamically reconfigurable architectures with tunable functionality and responsiveness, governed by the selection of suitable materials and cells. 相似文献
995.
996.
Left ventricular assist device patient maintained on home hemodialysis: A novel class of patients to the home dialysis population
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Ramy M. Hanna Daniel Cruz Umut Selamet Huma Hasnain Murray Kwon Arnold Baas James Wilson 《Hemodialysis international. International Symposium on Home Hemodialysis》2018,22(3):E36-E38
Severe heart failure is increasingly being managed by cardiac transplantation, and in some cases mechanical support devices serve as destination therapies. Left ventricular assist devices (LVADs) were approved for destination therapy for end stage heart failure patients before the more advanced total artificial heart modality became available. One common complication of mechanical assist device placement is acute kidney injury. Historically, patients with mechanical support devices have had to have inpatient hemodialysis until combined heart kidney transplant. Though, some units have started accepting LVAD patients in outpatient dialysis clinics. The cost of in center hemodialysis remains high and home dialysis modalities are becoming increasingly popular. We report the first patient with an LVAD to undergo training and successful home hemodialysis while awaiting combined heart kidney transplantation. 相似文献
997.
G. Paniagua Pardo A. Domínguez Pacheco S. A. Tomás A. Cruz Orea C. Hernandez Aguilar 《International Journal of Thermophysics》2018,39(10):118
In this study, photoacoustic spectroscopy (PAS) was used as an option to evaluate aging in vegetable seeds. Aged seeds were characterized by their decrease in germination and vigor, which are important quality measures to obtain healthy and uniform crops. The seed optical parameters obtained with this technique provide information about their composition and physiological quality attributes. Red lettuce and chard seeds, aged and non-aged, were used for these experiments. The thermal diffusivity (α) and optical absorption coefficient (β) were determined for a large number of aged and non-aged seeds. In the case of β, this optical parameter was obtained in the spectral range from 250 nm to 750 nm. The results show statistically significant differences in β values for both types of seeds, with higher values found for non-aged specimens. Also images of scanning electron microscopy for aged and non-aged seeds corroborate marked differences between them. This PAS approach represents a promising method to be applied in the evaluation of seed quality in the food industry. 相似文献
998.
The high-T
c superconducting system YBa2Cu3O:Li (123) was investigated by microwave absorption. The effect of neutron irradiation on the 123 phase as well as the dependence of the resulting modification both on the neutron fluence and on the doping behavior with Li are discussed. The results show a significant improvement of the superconducting characteristics: critical temperature, phase homogeneity, and critical current densities for a certain neutron fluence. We have found that the optinum neutron fluence for irradiation is 4.98×1021 m–2. 相似文献
999.
We report the efficient operation of a continuous-wave, single-frequency, diode-pumped Nd:FAP laser at 1.126 mum. When frequency quadrupled, such a laser might be used as a local oscillator for an optical frequency standard based on the single-photon (2)S(1/2)-(2)D(5/2) electric quadrupole transition of a trapped and laser-cooled (199)Hg(+) ion. Since the frequencies of the atomic transition and the laser are harmonically related, this scheme helps to simplify the measurement of the S-D clock transition frequency by a phase-coherent chain to the cesium primary frequency standard. 相似文献
1000.
Jeffrey A. Cruz Xi Yin Xiaoming Liu Saif M. Imran Daniel D. Morris David M. Kramer Jin Chen 《Machine Vision and Applications》2016,27(5):735-749
Among many applications of machine vision, plant image analysis has recently began to gain more attention due to its potential impact on plant visual phenotyping, particularly in understanding plant growth, assessing the quality/performance of crop plants, and improving crop yield. Despite its importance, the lack of publicly available research databases containing plant imagery has substantially hindered the advancement of plant image analysis. To alleviate this issue, this paper presents a new multi-modality plant imagery database named “MSU-PID,” with two distinct properties. First, MSU-PID is captured using four types of imaging sensors, fluorescence, infrared, RGB color, and depth. Second, the imaging setup and the variety of manual labels allow MSU-PID to be suitable for a diverse set of plant image analysis applications, such as leaf segmentation, leaf counting, leaf alignment, and leaf tracking. We provide detailed information on the plants, imaging sensors, calibration, labeling, and baseline performances of this new database. 相似文献