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11.
12.

Background and aims

Since accelerated atherosclerosis has been reported in systemic lupus erythematosus (SLE), predictive biomarkers of cardiovascular disease (CVD) are needed. Among non-traditional risk factors, bone mineral density (BMD) has been related to CVD. However, its role in SLE remains controversial. This study aims to analyze the associations of subclinical atherosclerosis with traditional and non-traditional CV risk factors.

Methods and results

In a cross-sectional study, atherosclerosis burden was compared between 112 female SLE patients and 31 controls. Plaque number and carotid intima-media wall thickness (cIMT) were assessed by ultrasonography. In a retrospective study, BMD determinations obtained 5-years before the ultrasonography assessment were analyzed in a subgroup of 62 patients. Plaque frequency was increased in SLE, even in patients without CV events or carotid wall thickening. cIMT was increased in patients with CVD, positively correlated with body mass index (BMI). Interestingly, a paradoxical effect of BMI on carotid parameters was observed. Whereas underweight patients (BMI < 20) showed increased prevalence of carotid plaques with low cIMT, those with BMI > 30 showed higher cIMT and plaque burden. Overweight patients (25 < BMI<30) exhibited both elevated cIMT and plaque number. BMI was an independent predictor of BMD. In our retrospective study, patients with either clinical or subclinical CVD exhibited lower BMD levels than their CV-free counterparts. A low lumbar spine BMD independently predicted CVD development after adjusting for confounders.

Conclusion

SLE was associated with a higher subclinical atherosclerosis burden, a bimodal effect being observed for BMI. Decreased BMD can be a CV risk biomarker in SLE.  相似文献   
13.
ABSTRACT

Various machine learning techniques have been developed for keratoconus detection and refractive surgery screening. These techniques utilize inputs from a range of corneal imaging devices and are built with automated decision trees, support vector machines, and various types of neural networks. In general, these techniques demonstrate very good differentiation of normal and keratoconic eyes, as well as good differentiation of normal and form fruste keratoconus. However, it is difficult to directly compare these studies, as keratoconus represents a wide spectrum of disease. More importantly, no public dataset exists for research purposes. Despite these challenges, machine learning in keratoconus detection and refractive surgery screening is a burgeoning field of study, with significant potential for continued advancement as imaging devices and techniques become more sophisticated.  相似文献   
14.

Background

Pure mucinous breast cancer (PMBC) is a rare pathologic type of breast cancer, the prognostic factors of which have not been clearly defined. This study aimed to analyze the prognostic markers and distribution of 21-gene recurrence score (RS) in patients with PMBC.

Patients and Methods

Utilizing the Surveillance, Epidemiology, and End Results (SEER) database, a retrospective analysis of PMBC cases was conducted. Multivariate analyses were used to evaluate the indicators for prognosis and the correlations between RS and traditional clinicopathologic characteristics. Disease was subdivided into 4 molecular phenotypes using estrogen receptor (ER) status and tumor grade.

Results

Of the 8048 patients, most had ER-positive and node-negative tumors. Multivariate analysis revealed that molecular phenotype as well as age, race, tumor size, and lymph node status was an independent prognostic factor for patients with PMBC (P < .05). The 5-year breast cancer–specific survival of patients among different phenotypes was significantly different (97.9% for ER-positive and grade I tumor, 96.9% for ER-positive and grade II-III tumor, 96% for ER-negative and grade I tumor, 90.1% for ER-negative and grade II-III tumors, P < .001). The proportions of patients categorized into low, intermediate, and high RS risk group were 64.9%, 31.9%, and 3.2%, respectively. Grade, progesterone receptor status, and age were identified as independent variables associated with RS.

Conclusion

PMBC had favorable biological features and relatively good prognosis. Molecular phenotype as well as age, race, tumor size, and lymph node status were independent prognostic markers. Furthermore, age, progesterone receptor status, and grade could independently predict RS.  相似文献   
15.
Lin  Hua  Li  Muwei  Zhan  Yang  Lin  Li  Yang  Kun  Hu  Shimin  Han  Ying 《Brain imaging and behavior》2021,15(4):1739-1747

The ε4 allele of the APOE gene is thought to increase risk from amnestic mild cognitive impairment (aMCI) to Alzheimer’s disease. Cognitive decline in the condition is increasingly considered to worsen functional disconnections in brain network composed of gray matter and white matter. Nevertheless, Whether APOEε4 targets specific white matter functional connectivity in patients with aMCI remains mostly unexplored, mainly due to the challenges of detecting BOLD signals in white matter. Here, we applied a novel approach to investigate APOEε4-related specific bundles and cortical area alterations in aMCI subjects, in order to characterize white matter-gray matter functional connectivity differences throughout the brain. We analyzed 75 patients with aMCI and 76 demographically matched normal controls. The aMCI APOEε4 carriers showed decreased functional connectivity located at left corticospinal tract, bilateral posterior limb of internal capsule, and right temporopolaris, which was different from the regions of aMCI-related changes. We further found that recognition scores were positively associated with the right temporopolaris in aMCI APOEε4 carriers. Collectively, the data provide new evidence that APOEε4 genotype exerts a negative impact on neural activity in both gray and white matter in aMCI, which potentially contributes to functional disconnection and memory decline. A novel method provides full-scale measuring effect of disease conditions on functional architecture throughout the brain. Trial registration: https://www.ClinicalTrials.gov (Identifier: NCT02225964). Registered January 2014.

  相似文献   
16.
We assessed the relationships among HIV-related social and behavioral outcomes resulting from an adolescent-focused HIV structural change initiative in eight urban sites operating Connect-to-Protect coalitions. Over a 4-year period, annual cross-sectional panels of adolescents (N = 2248) completed an audio-computer-assisted interview, providing data on satisfaction with their communities as adolescent-supportive environments, internalized HIV stigma, lifetime HIV-testing, lifetime sexual risk-taking and number of sexual partners in the prior year. We used structural equation modeling to estimate hypothesized links between time since coalition mobilization to our social and behavioral outcomes. Over the 4 years, adolescents perceived their communities to become more supportive (p < .05). Positive perceptions of community support were associated with lower lifetime HIV sexual risk (p < .05). The effect of time on risk behavior was mediated by perceptions of community support. Stigma was unchanged over time. Stigma had damaging effects on risk behavior, effects which were also mediated by perceptions of community support. Special efforts are needed to address the deleterious effect of HIV stigma on high-risk urban adolescents.  相似文献   
17.
Aims: To investigate the value of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) in a cohort of a community’s residents who were diagnosed as pre-diabetes, and to evaluate the association of VAT and SAT with insulin resistance.

Methods: This study was based on cross-sectional analysis of data from 107 adults. VAT and SAT were assessed by computed tomography. Insulin resistance was defined by homeostasis model assessment of insulin resistance >2.69. The relationship of VAT and SAT with insulin resistance were examined by linear regression. Logistic regression was used to analyze the association of VAT and SAT with insulin resistance.

Results: A total of 87 subjects had VAT ≥100?cm2. Thirty-six out of 107 (33.6%) subjects were detected to have insulin resistance, 71 were normal (66.4%), and all had insulin resistance with VAT ≥100?cm2. VAT (r?=?0.378, p?r?=?0.357, p?p?=?.003), but that of SAT was lost.

Conclusion: Pre-diabetic subjects with insulin resistance had elevated levels of VAT. VAT was more strongly associated with insulin resistance than SAT in Chinese subjects with pre-diabetes.  相似文献   
18.
A new homoisoflavanone, (3R)-5-hydroxy-7-methoxyl-3-(2′-hydroxy-4′- methoxybenzyl)-chroman-4-one (1), together with six known analogs, were isolated from the rhizomes of Polygonatum sibiricum. Their structures were elucidated on the basis of extensive spectroscopic analysis. All compounds were tested for their estrogenic activity using the MCF-7 estrogenresponsive human breast cancer cell lines. At a dose of 0.1 μmol/L, compounds 17 exhibited significant proliferative effects on MCF-7 cells compared with E2. The molecular docking study results indicated that the activity of compounds 3, 5, 6, and 7 may be the binding with ERR.  相似文献   
19.
The increase in multidrug resistance among colon cancer cells presents a challenge for the development of effective therapies. Small-molecule analogues of second mitochondria-derived activator of caspase (SMAC) mimetic in association with mixed lineage kinase domain-like protein (MLKL)-pDNA and z-VAD-fmk have shown ideal antitumor effects in colon cancer cells in vitro via induction of RIP3-dependent necroptosis. To achieve synergistic antitumor effects in vivo, liposomes loaded with SMAC mimetic, MLKL-pDNA and z-VAD-fmk have been developed using novel lipid fusion methods to co-localise the molecules of interest within the tumour cells. The co-encapsulation liposome (MLKL-zVAD-BV6-LP) had a high entrapment efficiency of approximately 95% for both zVAD and BV6 and was able to condense MLKL-pDNA very well. The vectors showed good biocompatibility, tumour targeting and small-molecule co-localisation. In a CT26 mouse model, the MLKL-zVAD-BV6-LP exhibited a tumour-suppression rate of over 60% in vivo, which was significantly higher than that of both the null-liposome and coadministration groups. Above all, the co-encapsulation system provided a novel approach to combination tumour therapy.  相似文献   
20.
目的构建体外百草枯(paraquat,PQ)细胞纤维化模型,观察PQ对A549细胞中解整合素-金属蛋白酶17(ADAM17)表达的影响,探讨ADAM17在PQ中毒致肺纤维化中的作用。方法体外培养A549细胞,分为正常对照组、不同浓度PQ组,应用CCK-8检测细胞活力,筛选PQ浓度和时间,显微镜下观察细胞形态,ELISA测定各组纤维化标志物I型胶原(type I collagen,Col I)和纤连蛋白(fibronectin,FN)的表达,建立细胞纤维化模型;免疫细胞化学检测A549细胞中ADAM17的分布情况,RT-PCR和Western blot分别半定量检测ADAM17 mRNA及蛋白水平的表达情况。结果(1)随着PQ浓度增加及作用时间延长,A549细胞活力呈下降趋势,差异有统计学意义(P〈0.05),呈剂量依赖性和时间依赖性。(2)正常的A549细胞融合呈铺路石样生长,排列比较紧密,经PQ诱导后细胞排列较松散,细胞间连接变疏松,部分细胞溶解、死亡。(3)ELISA显示,随PQ浓度增加,Col I和FN表达增强,差异有统计学意义(P〈0.05);随PQ时间延长,Col I和FN表达也逐渐增强,差异有统计学意义(P〈0.05),成功建立PQ细胞纤维化模型。(4)免疫细胞化学显示,ADAM17在A549细胞胞浆表达。(5)RT-PCR和Western blot表明,随着PQ浓度增加,ADAM17 mRNA及蛋白水平表达明显增加,差异有统计学意义(P〈0.05),以PQ 200 umol/L时最为明显。随着PQ作用时间延长,ADAM17 mRNA及蛋白表达水平也明显增加,差异有统计学意义(P〈0.05),在24 h达到高峰。结论百草枯可引起肺泡上皮细胞形态学改变,导致细胞损伤,成功建立细胞的纤维化模型,对A549细胞的毒性作用具有剂量和时间依赖性。ADAM17在PQ诱导的A549细胞中过表达,可能参与了百草枯诱导的肺纤维化过程。  相似文献   
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