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81.
The current study aimed to identify the primary informal caregivers of a group of urban HIV+ adults (n = 250) and to determine relationships between demographic, medical, and substance use characteristics and caregivers types. Reported caregiver types included 36.8% familial, 22.4% significant other, and 22.8% institutional or other caregiver relationships. The remaining 18% of the sample reported having no individual that rendered informal care. Factors associated with the absence of an informal caregiver included African American race and low education. Hispanic participants reported the highest frequency of family caregivers while participants with a history of substance disorder were less likely to identify a significant other as a caregiver. This study demonstrates the evolving nature of informal caregiving in HIV, race- and education-related disparities in the absence of primary caregivers, and the importance of sociocultural and demographic factors in the study of HIV caregiving. Research supported by R24MH59724 from the National Institutes of Health.  相似文献   
82.
The development of new modes of diagnosis and targeted therapy for lung cancer is dependent on the identification of unique cell surface features on cancer cells and isolation of reagents that bind with high affinity and specificity to these biomarkers. We recently isolated a 20-mer peptide which binds to the lung adenocarcinoma cell line, H2009, from a phage-displayed peptide library. We show here that the cellular receptor for this peptide, TP H2009.1, is the uniquely expressed integrin, alphavbeta6, and the peptide binding to lung cancer cell lines correlates to integrin expression. The peptide is able to mediate cell-specific uptake of a fluorescent nanoparticle via this receptor. Expression of alphavbeta6 was assessed on 311 human lung cancer samples. The expression of this integrin is widespread in early-stage nonsmall cell lung carcinoma (NSCLC). Log-rank test and Cox regression analyses show that expression of this integrin is significantly associated with poor patient outcome. Preferential expression is observed in the tumors compared with the surrounding normal lung tissue. Our data indicate that alphavbeta6 is a prognostic biomarker for NSCLC and may serve as a receptor for targeted therapies. Thus, cell-specific peptides isolated from phage biopanning can be used for the discovery of cell surface biomarkers, emphasizing the utility of peptide libraries to probe the surface of a cell.  相似文献   
83.
We examined the leptin response and related hormones during and after two sub-maximal exercise protocols in trained and untrained subjects. During this study, plasma concentrations of leptin [Lep], insulin [I], cortisol [C], growth hormone [GH], glucose [G] and lactate [La] were measured. 7 elite volleyball trained players (TR) and 7 untrained (UTR) subjects (percent body fat: 13.2 ± 1.8 versus 15.7 ± 1.0, p < 0.01, respectively) were examined after short and prolonged sub-maximal cycling exercise protocols (SP and PP). Venous blood samples were collected before each protocol, during, at the end, and after 2 and 24 h of recovery. SP and PP energy expenditures ranged from 470 ± 60 to 740 ± 90 kcal for TR and from 450 ± 60 to 710 ± 90 kcal for UTR, respectively. [Lep] was related to body fat percentage and body fat mass in TR (r = 0. 84, p < 0.05 and r = 0.93, p < 0.01) and in UTR (r = 0.89, p < 0.01 and r = 0.92, p < 0. 01, respectively). [Lep] did not change significantly during both protocols for both groups but was lower (p < 0.05) in all sampling in TR when compared to UTR. Plasma [I] decreased (p < 0.01) and [GH] increased (p < 0.01) significantly during both SP and PP and these hormones remained lower (I: p < 0.01) and higher (GH: p < 0.01) than pre-exercise levels after a 2-h recovery period, returning to base-line at 24-h recovery. Plasma [La] increased (p < 0.01) during both protocols for TR and UTR. There was no significant change in [C] and [G] during and after both protocols for all subjects. It is concluded that 1) leptin is not sensitive to acute short or prolonged sub-maximal exercises (with energy expenditure under 800 kcal) in volleyball/ anaerobically trained athletes as in untrained subjects, 2) volleyball athletes showed significantly lower resting and exercise leptin response with respect to untrained subjects and 3) it appears that in these anaerobically trained athletes leptin response to exercise is more sensitive to the level of energy expenditure than hormonal or metabolic modifications induced by acute exercise.

Key points

  • Trials concerning acute exercise and leptin indicated discrepant results.
  • Acute exercise with energy expenditure higher than 800 kcal can decrease leptinemia.
  • Elite volleyball players presented decreased leptin levels than untrained subjects.
Key words: Hormones, anaerobic training, acute exercise, body fat.  相似文献   
84.
There often exists a discrepancy between the information health care professionals (HCPs) provide to patients in preoperative teaching sessions and the information patients perceive as important. This study’s purpose was to determine what information patients undergoing a lung cancer surgical resection wanted to learn before and after their surgery and also to uncover the information HCPs currently provide to these patients. Ten patients were interviewed preoperatively and postoperatively, and eleven HCPs involved in both their preoperative and postoperative care were interviewed. Emerging themes were noted. Patients reported that the most helpful aspects of the preoperative education included surgical details and the importance of physiotherapy, including exercises. Postoperatively, patients wished they had known more about postoperative pain. HCPs provided information that they felt prepared, informed and empowered their patients. Overall, patients expressed satisfaction with the information they received; they felt prepared for their surgery but not for postoperative pain control.  相似文献   
85.
86.
Epidermoid cyst is a frequent benign tumor. It gives rise to destruction of adjoining tissues, chiefly in the skull. The pelvic epidermoid cyst is rare. We report the second case of giant pelvic epidermoid cyst with a 25-year-old girl. Ultrasound exploration and computed tomography evoked an ovarian origin. The surgery discovers an epidermoid cyst under the peritoneum. Ovaries and uterus were undamaged. We realized an evacuation of cyst, which contained lamellas of keratin. Histology allowed confirmation of diagnosis. The patient is always observed after 18 months.  相似文献   
87.
88.
In this study, we demonstrate that the crystallization process of CsPbI2Br films can be modulated when small amounts of additives are added to the precursor solution, leading to the formation of the bright brownish α-phase perovskite films with high orientation along the [100] crystallographic direction. Doped CsPbI2Br films exhibit improved crystallinity, with high coverage, large grain size and pinhole-free surface morphology, suitable for making high performance optoelectronic devices. We also explored the role of Cl in the photophysical properties of CsPbI2Br perovskite films using the temperature dependent photoluminescence technique. We found that the Cl ions enhance the photoluminescence emission by reducing the density of trap states, and also decrease the exciton binding energy from (22 ± 3) meV to (11 ± 2) meV. We believe this work contributes to understanding the effect of doping on the crystallization process with an in-depth insight into the photophysical properties of the cesium-based perovskite materials.

In this study, we demonstrate that in addition to improving the crystallization of CsPbI2Br films, the incorporation of Cl and hydroiodic acid in the precursor solution leads to the formation of films with high coverage and large grains size.  相似文献   
89.
Foodborne diseases caused by resistance of microorganisms to multiple antimicrobial agents have emerged as a major public health concern around the world. The search for potential antimicrobials has resulted in the emergence of metal nanoparticles for protection against these infections. In this study an eco-friendly and green approach was used to biosynthesize hybrid Ag/AgCl nanoparticles (NPs), using levan from Bacillus mojavensis as a stabilizing/reducing agent, with a high efficiency against a broad spectrum of foodborne bacteria as well as biofilm formations. The morphology and physicochemical characteristics of levan–Ag/AgCl NPs were investigated by transmission electron microscopy (TEM), X-ray diffraction (XRD), UV-vis spectroscopy (UV), dynamic light scattering (DLS) and thermogravimetric analysis (TGA). The hybrid levan–Ag/AgCl was evaluated for antibacterial activity against foodborne pathogenic bacteria (Escherichia coli, Klebsiella pneumoniae, Salmonella enterica, Pseudomonas aeruginosa, Staphylococcus aureus, Micrococcus luteus, Listeria monocytogenes, Enterococcus faecalis, Bacillus subtilis and Bacillus thuringiensis). The study demonstrated the strong efficiency of hybrid levan–Ag/AgCl NPs as a potent inhibitor against all tested strains, with much higher activity against Gram-negative than Gram-positive bacteria. Furthermore, bacterial strains were found to be highly sensitive to hybrid levan–Ag/AgCl NPs in comparison to the tested antibiotics. As a possible application of levan–Ag/AgCl NPs as an additive in packaging, PVA films with different amounts of hybrid levan–Ag/AgCl NPs were prepared by casting and their antibacterial, mechanical, and optical properties and ability to expand the shelf life of beef meat were explored. Interestingly, the amount of Ag leached out from films was below the permissible limit. This work demonstrates the strong antibacterial action of hybrid levan–Ag/AgCl NPs and their potential use in bioactive packaging material.

Hybrid Ag/AgCl nanoparticles with high antibacterial activity were synthesised using bacterial levan.  相似文献   
90.
Multiple lines of evidence including recent imaging studies suggest that schizophrenia is associated with an imbalance of the dopaminergic system, entailing hyperstimulation of striatal dopamine (DA) D2 receptors and understimulation of cortical DA D1 receptors. This DA endophenotype presumably emerges from the background of a more general synaptic dysconnectivity, involving alterations in N-methyl-d-aspartate (NMDA) and glutamatergic (GLU) functions. Equally important is the fact that this DA dysregulation might further impair NMDA transmission. The first generation antipsychotic (FGA) drugs are characterized by high affinity to and generally high occupancy of D2 receptors. The efficacy of FGAs is limited by a high incidence of extrapyramidal side-effects (EPS). Second generation antipsychotic (SGA) drugs display reduced EPS liability and modest but clinically significant enhanced therapeutic efficacy. Compared to FGAs, the improved therapeutic action of SGAs probably derives from a more moderate D2 receptor blockade. We will review the effects of SGAs on other neurotransmitter systems and conclude by highlighting the importance of therapeutic strategies aimed at directly increasing prefrontal DA, D1 receptor transmission or NMDA transmission to enhance the therapeutic effect of moderate D2 receptor antagonism.  相似文献   
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