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1.
ABSTRACT

Chronotype reflects time of day preferences for performing daily activities. Previous research within Asian and European cohorts indicates evening chronotype is associated with elevated cardiometabolic risk. However, evidence is limited from population-based US cohorts, particularly among women in whom evening chronotype prevalence may become higher after middle-age, coinciding with life stages associated with higher cardiovascular disease (CVD) risk. This cross-sectional study evaluated associations of chronotype with overall cardiovascular health (CVH), health behaviors, and cardiometabolic risk factors among 506 women (mean age = 37 ± 16y, 62% racial/ethnic minority) in the American Heart Association (AHA)’s Go Red for Women Strategically-Focused Research Network cohort at Columbia University (New York City, NY, USA). Chronotype was assessed using the validated Morningness-Eveningness Questionnaire (MEQ) and categorized as “evening”, “intermediate”, and “morning” chronotypes. Health behaviors (diet, physical activity, and sleep) were assessed using validated questionnaires. Anthropometrics, clinical blood pressure, and blood biomarkers were assessed at the clinic visit. CVH was evaluated using the AHA Life’s Simple 7 (LS7) metrics; LS7 scores of 0–8 and 9–14 were considered indicative of poor and moderate-to-high CVH, respectively. Linear and logistic regression models adjusted for age, race/ethnicity, education, health insurance, and menopausal status were used to examine associations of MEQ scores and chronotype categories with overall CVH, clinical cardiometabolic risk factors, and health behaviors. Overall, 13% of women identified as evening chronotypes, while 55% and 32% reported being intermediate and morning types. In linear models, higher MEQ scores were associated with higher AHA LS7 scores (β(SE) = 0.02(0.01); p = .014), indicative of more favorable CVH, and with health behaviors not included in the LS7. Higher MEQ scores were also associated with lower Pittsburgh Sleep Quality Index, i.e. better sleep quality, (β(SE) = ?0.07(0.02), p < .0001), lower insomnia severity (β(SE) = ?0.14(0.01), p < .0001), shorter time to fall asleep (β(SE) = ?0.28(0.14), p = .044), and less sedentary time (β(SE) = ?0.11(0.03), p = .001). In logistic regression models, evening chronotype, compared to intermediate/morning type, was associated with higher odds of having poor CVH (OR(95%CI):2.41(1.20–4.85)), not meeting AHA diet (OR(95%CI):2.89(1.59–5.23)) and physical activity guidelines (OR(95%CI):1.78(1.03–3.07)), and having short sleep (OR(95%CI):2.15(1.24–3.73)) or insomnia (OR(95%CI):2.69(1.53–4.75)). The evening type compared to morning type was also associated with being a current smoker (OR(95%CI):2.14(1.02–4.52)) and having poor sleep quality (OR(95%CI:2.35(1.27–4.37)) and long sleep onset latency (OR(95%CI:1.89(1.00–3.56)). In our cohort of women, evening chronotype was related to poor CVH, likely driven by its influence on health behaviors. These findings, although warranting confirmation prospectively in other populations, suggest chronotype is an important factor to consider and possibly target when designing lifestyle interventions for CVD prevention.  相似文献   
2.
BACKGROUND: Deletion of chromosome 16q is frequently associated with diverse tumors. Numerous studies strongly suggest the presence of one or more tumor suppressor genes on chromosome 16q22 to 16qter including the widely studied cadherin gene family. However, the specific tumor suppressor genes residing in this region need better definition and characterization. MATERIAL AND METHODS: Standard molecular biology approaches have been used to clone and characterize the DERPC cDNA and its protein product on chromosome 16q22.1. Northern blotting was used to define the expression pattern in a multiple human tissue blots. DERPC expression was examined in multi-tumor array (Clontech, CA, USA) dot blot as well as in laser capture microdissection (LCM) derived prostate cancer (CaP) specimens by quantitative RT-PCR. Western blot analysis and a fluorescent microscopy were used to characterize the molecular size and the cellular location of green fluorescent protein (GFP)-tagged DERPC fusion proteins. A colony formation assay was conducted to determine the effects of DERPC expression on tumor cell growth. RESULTS: A novel gene DERPC (Decreased Expression in Renal and Prostate Cancer) was identified and characterized. DERPC encoded a strong basic, proline- and glycine-rich nuclear protein. DERPC was ubiquitously expressed, with abundant expression in kidney, skeletal muscle, testis, liver, ovary, and heart and moderate expression in prostate. DERPC expression was reduced in renal (67%) and prostate tumors (33%). Expression of DERPC has inhibitory potential on CaP cell growth. Further, overexpression of DERPC in LNCaP cells caused alterations of nuclear morphology. CONCLUSION: This study suggests that decreased expression of DERPC may be implicated in tumorigenesis of renal and CaPs.  相似文献   
3.
In this study, a novel method to probe molecular interactions and binding of human hemoglobin (Hb) with nanodiamond (ND) was introduced based on the surface tension measurement. This method complements conventional techniques, which are basically done by zeta potential and dynamic light scattering (DLS) measurements, near and far circular dichroism (CD) spectroscopy, intrinsic and extrinsic fluorescence spectroscopy. Addition of ND to Hb solution increased the surface tension value of Hb–ND complex relative to those of Hb and ND molecules. The zeta potential values reveled that Hb and ND provide identical charge distribution at pH 7.5. DLS measurements demonstrated that Hb, ND, and ND–Hb complex have hydrodynamic radiuses of 98.37 ± 4.57, 122.07 ± 7.88 nm and 62.27 ± 3.70 at pH of 7.5 respectively. Far and near UV-CD results indicated the loss of α-helix structure and conformational changes of Hb, respectively. Intrinsic fluorescence data demonstrated that the fluorescence quenching of Hb by ND was the result of the static quenching. The hydrophobic interaction plays a pivotal role in the interaction of ND with Hb. Fluorescence intensity changes over time revealed conformational change of Hb continues after the mixing of the components (Hb–ND) till 15 min, which is indicative of the denaturation of the Hb relative to the protein control. Extrinsic fluorescence data showed a considerable enhancement of the ANS fluorescence intensity of Hb–ND system relative to the Hb till 60 nM of ND, likely persuaded by greater exposure of nonpolar residues of Hb hydrophobic pocket. The remarkable decrease in Tm value of Hb in Hb–ND complex exhibits interaction of Hb with ND conducts to conformational changes of Hb. This study offers consequential discrimination into the interaction of ND with proteins, which may be of significance for further appeal of these nanoparticles in biotechnology prosecution.  相似文献   
4.
The BRG1 catalytic subunit of SWI/SNF-related complexes is required for mammalian development as exemplified by the early embryonic lethality of Brg1 null homozygous mice. BRG1 is also a tumor suppressor and, in mice, 10% of heterozygous (Brg1(null/+)) females develop mammary tumors. We now demonstrate that BRG1 mRNA and protein are expressed in both the luminal and basal cells of the mammary gland, raising the question of which lineage requires BRG1 to promote mammary homeostasis and prevent oncogenic transformation. To investigate this question, we utilized Wap-Cre to mutate both Brg1 floxed alleles in the luminal cells of the mammary epithelium of pregnant mice where WAP is exclusively expressed within the mammary gland. Interestingly, we found that Brg1(Wap-Cre) conditional homozygotes lactated normally and did not develop mammary tumors even when they were maintained on a Brm-deficient background. However, Brg1(Wap-Cre) mutants did develop ovarian cysts and uterine tumors. Analysis of these latter tissues showed that both, like the mammary gland, contain cells that normally express Brg1 and Wap. Thus, tumor formation in Brg1 mutant mice appears to be confined to particular cell types that require BRG1 and also express Wap. Our results now show that such cells exist both in the ovary and the uterus but not in either the luminal or the basal compartments of the mammary gland. Taken together, these findings indicate that SWI/SNF-related complexes are dispensable in the luminal cells of the mammary gland and therefore argue against the notion that SWI/SNF-related complexes are essential for cell survival. These findings also suggest that the tumor-suppressor activity of BRG1 is restricted to the basal cells of the mammary gland and demonstrate that this function extends to other female reproductive organs, consistent with recent observations of recurrent ARID1A/BAF250a mutations in human ovarian and endometrial tumors.  相似文献   
5.
6.
Polyunsaturated fatty acids, especially gamma linolenic acid (GLA), are potentially useful agents in the treatment of cancer. Cunninghamella echinulata, a fungus species that is able to synthesize GLA, when cultivated under nitrogen‐limited conditions in a medium having glucose as carbon and energy source, accumulated 32–35% of lipids containing 11–18% GLA. The conversion yield of glucose to lipid was around 0.11 g per gram of glucose consumed while the lipid production was 5 g/L. Fatty acid lithium salts (FALS) were prepared from the total Cunninghamella lipids and studied for their effects on HL‐60 human leukemic cells. Cytotoxicity of FALS on HL‐60 leukemic cells was linearly related to the FALS concentration. High FALS concentration (i.e. 15 and 20 μg/mL) induced DNA fragmentation, while concurrent treatment of cells with H2O2 (at 100 μM) and FALS resulted in enhanced cytotoxicity of H2O2. However, when FALS were employed at low concentrations (i.e. 5 and 10 μg/mL), they demonstrated a protective effect on HL‐60 cells against H2O2 genotoxicity, whereas at 20 μg/mL FALS enhanced the ability of H2O2 to induce DNA fragmentation. It is concluded that FALS derived from C. echinulata lipids could be an effective preparation against HL‐60 human leukemic cells.  相似文献   
7.
In this work, the benzimidazole-pyrrole conjugates 6ah and benzimidazole-tetracycles conjugates 1214 were prepared. The cytotoxicity of the compounds 3, 4ah, 6ah, 8, 10 and 1214 was tested against lung cancer cell line A549. Compound 6b exhibited higher activity than the bis-benzoxazole natural product (UK-1), the standard. The tested 4g,h, 6ah, 10 and 1214 exhibited remarkable cytotoxicity activity against breast cancer cell line MCF-7 with higher activity than tamoxifen. Furthermore, compound 4h was found to be also more potent than doxurubicin. The antitumor promotion activity of synthesized compounds 4g,h, 6ah, 10 and 1214 has been estimated by studying their possible inhibitory effects on EBV-EA activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). Among the studied compounds, the inhibitory activities of compounds 8, 13 and 14 demonstrated strong inhibitory effects on the Epstein–Barr virus early antigen (EBV-EA) activation without showing any cytotoxicity on the Raji cells and their effects being stronger than that of a representative control, oleanolic acid.Moreover, the molecular docking of the new compounds into plasminogen activator (uPA) receptor has been in correlation with the antitumor activity. All synthesized compounds 3, 4ah, 6ah, 8, 10 and 1214 were docked into same groove of the binding site of the native co-crystalized (4-iodobenzo[b]thiophene-2-carboxamidine) ligand (PDB code:1c5x) for activity explaination. Compounds 4h, 6b and 13, giving the best docking results, were further studied to estimate their effect on the level of uPA using AssayMax human urokinase (uPA) ELISA kit. In case of A549 cell line, compound 6 exhibited similar activity to MMC, and for MCF-7 cell line, compound 4h exhibited similar activity to doxorubicin, in inhibiting the expression of uPA.  相似文献   
8.
Fungi are among the most important aeroallergens. The aim of this study was to provide aeromycological baseline information about Zarqa area, Jordan, for the first time. During the entire survey and from 170 settle plate exposures, a total of 735 mould- and 274 yeast colony-forming units (CFU) were collected. mould colonies were assigned to 35 genera and 59 species. The highest abundance was attributed to Cladosporium with a percentage of 29.1% of the total colony count followed by Fusarium 20%, Alternaria 7.7%, Ulocladium 6.5% Penicillium 4.2% and then Aspergillus 3.6%. Cladosporium showed one peak in October while Aspergillus and Penicillium peaked in September. Fusarium peaked in May and August and Alternaria in March and July. However, Ulocladium showed almost the same abundance from March to June and then in September and December. A double peak in total colony count and fungal diversity was found, the first was in March and the second in November–December. Significant differences of total fungal colony counts favouring the 1500 hours collection time over that at 1000 hours were found between November and January while no such significant differences were obtained between February and April. Our results also indicated differences in species composition between the two periods in different months. Spores of the three abundant species, Cladosporium, Fusarium and Alternaria, might favour high release in the 1500 hours period during winter while having a similar incidence during the two periods in the spring months.  相似文献   
9.
Tremendous efforts have been invested in the development of the internet of things during the past 10 years. Implantable sensors still need embedded miniaturized energy harvesting devices, since commercialized thin films and microbatteries do not provide sufficient power densities and suffer from limited lifetime. Therefore, micro‐supercapacitors are good candidates to store energy and deliver power pulses while providing non‐constant voltage output with time. However, multistep expensive protocols involving mask aligners and sophisticated cleanrooms are used to prepare these devices. Here, a simple and versatile laser‐writing procedure to integrate flexible micro‐supercapacitors and microbatteries on current‐collector‐free polyimide foils is reported, starting from commercial powders. Ruthenium oxide (RuO2)‐based micro‐supercapacitors are prepared by laser irradiation of a bilayered tetrachloroauric acid (HAuCl4 · 3H2O)–cellulose acetate/RuO2 film deposited by spin‐coating, which leads to adherent Au/RuO2 electrodes with a unique pillar morphology. The as‐prepared microdevices deliver 27 mF cm?2/540 F cm?3 in 1 m H2SO4 and retain 80% of the initial capacitance after 10 000 cycles. This simple process is applied to make carbon‐based micro‐supercapacitors, as well as metal oxide based pseudocapacitors and battery electrodes, thus offering a straightforward solution to prepare low‐cost flexible microdevices at a large scale.  相似文献   
10.
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