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91.
Persons with advanced human immunodeficiency virus type one (HIV-1) infection seek medical advice for a wide range of neurological disorders including, but not limited to, peripheral neuropathy, toxoplasmosis, cryptococcal meningitis, cytomegalovirus retinitis progressive multifocal leukoencephalopathy, lymphoma and dementia. The diagnosis of HIV-1-associated dementia (HAD) induced as a direct consequence of HIV infection of the brain comes commonly by exclusion. Diagnostic decisions can often be clouded by concomitant depression, motor impairments, and lethargy that follow debilitating immune suppression and weight loss. Indeed, cognitive, motor and behavior abnormalities underlie a variety of neurological dysfunctions associated with advanced HIV-1 infection. Thus, even combinations of clinical, laboratory and neuroimaging tests [for example, magnetic resonance imaging (MRI), computed tomography (CT), single photon emission computed tomography (SPECT) and positron emission tomography (PET)] often fail to provide conclusive diagnostic information. Nonetheless, the recent development of quantitative MR spectroscopic imaging has improved diagnostic possibilities for HAD. We are pleased to discuss these developments as well as taking a forward look into what will soon be made available to improve neuroimaging diagnostic precision. New MR and SPECT testing are being developed in our laboratories and elsewhere both for animal model systems and in humans with HIV-1 disease. Such tests can facilitate dynamic measures of HIV-1 neuropathogenesis providing information for disease events that even 2 years ago were unattainable.  相似文献   
92.
Abstract

In this work, the expression of secreted frizzled related protein 2 (SFRP2) in rheumatoid arthritis (RA) model rats and the mechanisms of SFRP2 on the RA pathogenesis were investigated. Data suggested that SFRP2 was significantly down-regulated in RA model rats compared with normal control, and overexpression of SFRP2 suppressed the RA pathogenesis and the canonical Wnt signaling in fibroblast-like synovial cells (FLS) from RA model rats, whereas knockdown of SFRP2 got an opposite observation. Interestingly, 5-azadC treatment up-regulated the SFRP2 expression, inhibited the FLS proliferation, suppressed the expression of IL-6 and IL-8 and the fibronectin production, suggesting that the decreased SFRP2 in RA model rats was due to the DNA methylation. Furthermore, DNMT1 knockdown up-regulated the SFRP2 expression, DNMT1 overexpression inhibited the SFRP2, and the quantitative methylation-specific PCR (qMSP) confirmed that the DNMT1 has direct methylation roles for the SFRP2 promoter, leading to a regulation of FLS proliferation and fibronectin expression in RA model rats. In addition, up-regulated MeCP2 was involved in the SFRP2 regulation and the pathogenesis of RA model rats, and MeCP2 and DNMT1 have synergistic inhibition roles in the SFRP2 expression. Combination of DNMT1 and DNA methylation may be a promising treatment strategy for individuals with RA in which SFRP2 is down-regulated.  相似文献   
93.
Study ObjectiveTo prospectively examine the association between sleep quality and incident cancer risk in the elderly.MethodsA total of 10,036 participants aged ≥50 years free of cancer at baseline from the English Longitudinal Study of Ageing at wave 4 (2008) were included, and followed up until 2016. The primary endpoint was new onset physician-diagnosed cancer. Sleep quality was assessed by four questions regarding the frequency of sleep problems and overall subjective feeling of sleep quality in the last month, with higher score denoting poorer sleep quality. The multivariable Cox regression model was used to calculate hazard ratio (HR) with 95% confidence interval (CI) for incident cancer risk according to sleep quality.ResultsAt 8-year follow-up, a total of 745 (7.4%) participants developed cancer. Compared with good sleep quality at baseline, HR (95% CI) for incident cancer risk was 1.328 (1.061, 1.662) for intermediate quality, 1.586 (1.149, 2.189) for poor quality. Similarly, compared with maintaining good sleep quality in the first 4 years, HR (95% CI) for incident cancer risk was 1.615 (1.208, 2.160) for maintaining intermediate quality and 1.608 (1.043, 2.480) for maintaining poor quality. The exclusion of participants with family history of cancer or abnormal sleep duration yielded consistent results.ConclusionsPoor sleep quality is positively associated with the long-term risk of developing cancer in an elderly cohort. Both medical staffs and the general public should pay more attention to improving sleep hygiene.  相似文献   
94.
95.
With the careful modulation of the relative ratio of Y3+/Eu3+and Y3+/Tb3+, two series of bimetallic RE-CPs (EuxY1−x and TbxY1−x) were successfully obtained through the isomorphous substitution method. Interestingly, the introduction of Y3+ ions does not change the fluorescence characteristic peak of 1-Eu and 1-Tb, but enhances its fluorescence lifetime and quantum yield. Experimental and theoretical simulation results show the co-doping process changes the intramolecular energy transfer process and reduces the non-radiative transition resulting from concentration quenching. Eu0.1Y0.9 and Tb0.1Y0.9 with the largest luminescence lifetime were selected as the representative research objects, their potential application for the detection of toxic metal ions and organic molecules was further investigated. Interestingly, Eu0.1Y0.9 and Tb0.1Y0.9 demonstrate high sensitivity and good selectivity towards Fe3+, Cr3+ and acetone. Besides, fine fluorescence visibility provides the necessary conditions for the preparation of simple and fast response fluorescent test papers in order to achieve real-time and convenient detection of these toxic materials.

Two series of doped coordination polymers (EuxY1−x and TbxY1−x) through isomorphous substitution method utilizing Y3+ in place of partial Eu3+/Tb3+ were obtained. The doped materials could detect Fe3+, Cr3+, and acetone selectively and sensitively.  相似文献   
96.
Doxorubicin hydrochloride (DOX) shows a powerful treatment effect on breast cancer. However, for its indiscriminate distribution after systemic administration, the therapeutic response of DOX will reduce and even result in serious adverse reactions during the long-term administration. To achieve better treatment, in this study we established a non-condensing sodium alginate-based nanoparticle-encapsulated DOX (DOX/NP), the surface of which was modified with cell-penetrating peptide LyP-1 (namely LyP-1-DOX/NP) to attain active targeting towards breast cancer cells. The size of LyP-1-DOX/NP was 138.50 ± 4.65 nm, with a polydispersity index (PDI) of 0.22 ± 0.02, and the zeta potential was 18.60 ± 0.49 mV. The drug loading efficiency (DLE) for the preparation was 91.21 ± 2.01%, with an encapsulation efficiency (EE) of 12.37 ± 0.35%. The nanoparticles exhibited good stability in vitro and slower release trend compared with free DOX in PBS at pH7.4. In vitro cytopharmacodynamics showed that LyP-1-DOX/NP had an excellent anti-breast cancer effect against MDA-MB-231 cells by the MTT test. The uptake amount of LyP-1-DOX/NP by MDA-MB-231 cells was much higher than that of free DOX or unmodified DOX/NP at all time points. Further in vivo pharmacokinetics studies showed that the concentration of LyP-1-DOX/NP was higher than that of free DOX or DOX/NP both in plasma and in tumor, suggesting its favorable long circulation and enhancing targeting property. The present study provides a promising strategy for using the LyP-1 cell-penetrating peptide to modify nanoparticles for enhancing their targeting ability towards breast cancer.

Doxorubicin hydrochloride (DOX) shows a powerful treatment effect on breast cancer.  相似文献   
97.
The effect of temperature on the toxicities of four diamide insecticides (chlorantraniliprole, cyantraniliprole, flubendiamide, tetraniliprole) against three lepidopteran insects (Helicoverpa armigera, Plutella xylostella, Athetis lepigone) were determined from 15 to 35 °C by exposing third-instar larvae to dip-treated cabbage leaf. The results indicated that increase in temperature led to an increase significantly and regularly in the toxicities of the four diamide insecticides against P. xylostella and H. armigera, but not for A. lepigone. The temperature coefficients (TCs) of the four diamide insecticides increased from 15 to 35 °C. Tetraniliprole for H. armigera (+825.83), chlorantraniliprole for P. xylostella (+315.65) and cyantraniliprole for H. armigera (+225.77) exhibited high positive TCs. For A. lepigone, temperature had a positively weak or no effect on the toxicities of most of the diamide insecticides from 20 to 30 °C, but a higher effect from 30 to 35 °C. In addition, the toxicities of chlorantraniliprole, cyantraniliprole and tetraniliprole all decreased from 15 to 20 °C. This study can guide pest managers in choosing suitable ambient field temperature when spraying diamide insecticides against lepidopteran insects.  相似文献   
98.
99.
目的 探讨药护协同管理在急性心肌梗死患者溶栓治疗中的实践效果.方法 将100例急性心肌梗死溶栓治疗的患者按数字随机法分为常规组(n=50)和协同管理组(n=50),常规组按照常规护理,协同管理组在此基础上实施药护协同管理,干预6个月后比较治疗效果.结果 两组入院后明确诊断至开始溶栓时间、冠脉有效灌注率和住院天数比较,协同干预组显著优于常规组,48h内恶性心律失常发生例数协同组显著少于常规组,差异有统计学意义(均P<0.05).两组患者溶栓治疗后12h、24 h、48 h、7d的LVEF值比较,差异有统计学意义(均P<0.05);出院后6个月心脏不良事件发生比例比较,差异无统计学意义(P>0.05).结论 药护协同管理能够有效缩短急性心肌梗死患者入院后至溶栓的时间,提高冠脉有效灌注,减少48 h内恶性心律失常发生和缩短住院天数,促进心功能恢复.  相似文献   
100.
By performing DNase I footprint and band-shift analyses of a 170-base-pair region of the murine thymidine kinase promoter, we identified an inducible DNA binding activity that we named Yi. Yi binding activity was not detected in G0 and G1 extracts, but it was observed as cells crossed the G1/S boundary. Yi proteins bind specifically to a consensus sequence (CCCNCNNNCT) found at three distinct sites in this promoter region. We also observed a murine Sp1 binding activity that was constitutive throughout the cell cycle. We propose that the G1/S-specific Yi binding is important for murine thymidine kinase gene regulation and perhaps also for initiation of DNA synthesis.  相似文献   
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