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191.
Objectives
Although many studies about breast contrast-enhanced ultrasound had been conducted, clear diagnostic criteria for evaluating enhancement patterns are still lacking. This study aims to identify significant indicators for breast contrast-enhanced ultrasound and to establish an initial scoring system.Materials and Methods
Totally 839 patients were included in the study. This study was divided into two parts. 364 patients were included in part 1 while 475 in part 2. Conventional ultrasound and contrast-enhanced ultrasound were used to examine each lesion. Only the cases in part 2 were also examined by elastography. In part 1, Logistic regression analysis was performed to predict significant variables. A 5-point scoring system was developed based on the results. In part 2, the scoring system was used to evaluate all the breast lesions. To evaluate the diagnostic efficacy of the new scoring system, it was compared with the system established for elastography and conventional ultrasound (BI-RADS).Results
Three independent variables, namely, lesion scope, margin, and shape were selected in the final step of the logistic regression analysis in part 1. In part 2, the area under the ROC (receiver operating characteristic) curve for the contrast-enhanced scoring system was 0.912. The difference in the diagnostic capabilities of the contrast-enhanced scoring system and elastography was not statistically significant (P = 0.17). The difference in the diagnostic capabilities of the contrast-enhanced scoring system and BI-RADS was statistically significant (P<0.001).Conclusions
The contrast-enhanced patterns of benign and malignant breast tumors are different. The application of a 5-point scoring system for contrast-enhanced ultrasound is clinically promising. 相似文献192.
Previous studies have reported that perinatal nicotine exposure causes development of hypertensive phenotype in adult offspring.
Aims
The present study was to determine whether perinatal nicotine exposure causes an epigenetic programming of vascular Angiotensin II receptors (ATRs) and their-mediated signaling pathway leading to heightened vascular contraction in adult offspring.Main methods
Nicotine was administered to pregnant rats via subcutaneous osmotic minipumps from day 4 of gestation to day 10 after birth. The experiments were conducted at 5 months of age of male offspring.Key Findings
Nicotine treatment enhanced Angitension II (Ang II)-induced vasoconstriction and 20-kDa myosin light chain phosphorylation (MLC20-P) levels. In addition, the ratio of Ang II-induced tension/MLC-P was also significantly increased in nicotine-treated group compared with the saline group. Nicotine-mediated enhanced constrictions were not directly dependent on the changes of [Ca2+]i concentrations but dependent on Ca2+ sensitivity. Perinatal nicotine treatment significantly enhanced vascular ATR type 1a (AT1aR) but not AT1bR mRNA levels in adult rat offspring, which was associated with selective decreases in DNA methylation at AT1aR promoter. Contrast to the effect on AT1aR, nicotine decreased the mRNA levels of vascular AT2R gene, which was associated with selective increases in DNA methylation at AT2R promoter.Significance
Our results indicated that perinatal nicotine exposure caused an epigenetic programming of vascular ATRs and their-mediated signaling pathways, and suggested that differential regulation of AT1R/AT2R gene expression through DNA methylation mechanism may be involved in nicotine-induced heightened vasoconstriction and development of hypertensive phenotype in adulthood. 相似文献193.
194.
Yi‐zhou Tan Dong‐dong Fei Xiao‐ning He Ji‐min Dai Rong‐chen Xu Xin‐yue Xu Jun‐jie Wu Bei Li 《Cell proliferation》2019,52(4)
L‐type voltage‐gated calcium ion channels (L‐VGCCs) have been demonstrated to be the mediator of several significant intracellular activities in excitable cells, such as neurons, chromaffin cells and myocytes. Recently, an increasing number of studies have investigated the function of L‐VGCCs in non‐excitable cells, particularly stem cells. However, there appear to be no systematic reviews of the relationship between L‐VGCCs and stem cells, and filling this gap is prescient considering the contribution of L‐VGCCs to the proliferation and differentiation of several types of stem cells. This review will discuss the possible involvement of L‐VGCCs in stem cells, mainly focusing on osteogenesis mediated by mesenchymal stem cells (MSCs) from different tissues and neurogenesis mediated by neural stem/progenitor cells (NSCs). Additionally, advanced applications that use these channels as the target for tissue engineering, which may offer the hope of tissue regeneration in the future, will also be explored. 相似文献
195.
Yanglansen Cui Kefeng Xiao Nicholas M. Bedford Xinxin Lu Jimmy Yun Rose Amal Da‐Wei Wang 《Liver Transplantation》2019,9(37)
Morphological engineering of nanosized transitional metal oxides shows great promise for performance improvement, yet limited efforts have been attempted to engineer the atomic structure. Oxygen vacancy (VO) can boost charge transfer leading to enhanced performance; yet excessive VO may impair the conductivity. Herein, tungsten oxide is atomically tailored by incorporating nitrogen heteroatoms into the oxygen vacancies. The efficient nitrogen‐filling into the oxygen vacancies is evidenced by the electron paramagnetic resonance spectroscopy and X‐ray absorption spectroscopy. The coordinated N atoms play a crucial role in facilitating the charge transfer and maintaining efficient lithium‐ion diffusion. Consequently, the tungsten oxide with N‐filled oxygen vacancies exhibits superior lithium‐ion storage performance. 相似文献
196.
Yang Gao Jie Mi Chang‐Long Zhang Xiao‐Qing Zhang Ya‐Jie Peng He Bao Hai‐Long Zhang 《化学与生物多样性》2019,16(1)
Continually phytochemical study of the roots of Heracleum dissectum had led to the isolation of three previously undescribed polyacetylene glycosides ( 1 – 3 ), together with seven known compounds, including one polyacetylene ( 8 ) and six coumarins ( 4 – 7 and 9 – 10 ) using diverse chromatographic methods. The structures of these three new compounds were characterized and identified as deca‐4,6‐diyn‐1‐yl β‐d ‐glucopyranosyl‐(1→6)‐β‐d ‐glucopyranosyl‐(1→2)‐β‐d ‐glucopyranoside ( 1 ), (8Z)‐dec‐8‐ene‐4,6‐diyn‐1‐yl β‐d ‐glucopyranosyl‐(1→6)‐β‐d ‐glucopyranosyl‐(1→2)‐β‐d ‐glucopyranoside ( 2 ), and (8E)‐dec‐8‐ene‐4,6‐diyn‐1‐yl β‐d ‐glucopyranosyl‐(1→6)‐β‐d ‐glucopyranosyl‐(1→2)‐β‐d ‐glucopyranoside ( 3 ) based on their physicochemical properties and extensive analyses of various spectroscopic data. Their triglycerides accumulating activities were assayed and the results showed that the three new polyacetylene glycosides ( 1 – 3 ) exhibited triglyceride accumulating activities in 3T3‐L1 adipocytes. 相似文献
197.
Jie Zhang Lei Wang Qianqian Song Mingbing Xiao Jie Gao Xiaolei Cao Wenjie Zheng 《International journal of biological sciences》2022,18(7):2729
Environmental and exogenous/ endogenous factors, in a setting of individual genetic predisposition, contribute to the cancer development. Over the years, epidemical evidence increasingly highlights the correlations of multiple cancer incentives and genetic alterations with cancer incidence. Unraveling the pivotal carcinogenesis events prompted by particular risk factors remarkably advances early surveillance and oncogenesis intervening. Traditional cell-based models and animal-based models are unrealistic and unreliable for translational study, respectively ascribing to the limited tumor heterogeneity and species-related variation. Organoid emerged as a fidelity model that well preserves the properties of its origin. With inherent quality of holistic perspective, organoid is therefore ideally suited for delineating the carcinogenesis under risk exposure, in favor of understanding pathogen-host interactions and alleviating cancer initiation. In this review, we have summarized the organoid model-based evidence that identified or validated carcinogenic risks, mainly including diet, aging, microbial infection, and chemical exposure. In addition, we envisioned the exciting prospect of organoid model in screening promising treatment and/or prevention during tumorigenesis. As a robust 3D in vitro system, organoid has been widespread applied in basial and clinical cancer research, which may elucidate crucial mechanisms of oncogenesis and develop novel targeting strategies. 相似文献
198.
Luyuan Zhang Yumin Wang Zhouying Peng Yuxiang Weng Zebin Fang Feng Xiao Chao Zhang Zuoxu Fan Kaiyuan Huang Yu Zhu Weihong Jiang Jian Shen Renya Zhan 《International journal of biological sciences》2022,18(8):3458
In recent years, with the standardization of radiomics methods; development of tools; and popularization of the concept, radiomics has been widely used in all aspects of tumor diagnosis; treatment; and prognosis. As the study of radiomics in cancer has become more advanced, the currently used methods have revealed their shortcomings. The performance of cancer radiomics based on single-modality medical images, which based on their imaging principles, only partially reflects tumor information, has been necessarily compromised. Using the whole tumor as a region of interest to extract radiomic features inevitably leads to the loss of intra-tumoral heterogeneity of, which also affects the performance of radiomics. Radiomics of multimodal images extracts various aspects of information from images of each modality and then integrates them together for model construction; thus, avoiding missing information. Subregional segmentation based on multimodal medical image combinations allows radiomics features acquired from subregions to retain tumor heterogeneity, further improving the performance of radiomics. In this review, we provide a detailed summary of the current research on the radiomics of multimodal images of cancer and tumor subregion-based radiomics, and then raised some of the research problems and also provide a thorough discussion on these issues. 相似文献
199.
200.
Yin Yang Dionisios Youlatos Alison M Behie Roula Al Belbeisi Zhipang Huang Yinping Tian Bin Wang Linchun Zhou Wen Xiao 《动物学报(英文版)》2022,68(4):401
Studies on positional behavior and canopy use are essential for understanding how arboreal animals adapt their morphological characteristics and behaviors to the challenges of their environment. This study explores canopy and substrate use along with positional behavior in adult black snub-nosed monkeys Rhinopithecus strykeri, an endemic, critically endangered primate species in Gaoligong Mountains, southwest China. Using continuous focal animal sampling, we collected data over a 52-month period and found that R. strykeri is highly arboreal primarily using the high layers of the forest canopy (15–30 m), along with the terminal zone of tree crowns (52.9%), medium substrates (41.5%), and oblique substrates (56.8%). We also found sex differences in canopy and substrate use. Females use the terminal zones (56.7% versus 40.4%), small/medium (77.7% versus 60.1%), and oblique (59.9% versus 46.5%) substrates significantly more than males. On the other hand, males spend more time on large/very large (39.9% versus 22.3%) and horizontal (49.7% versus 35.2%) substrates. Whereas both sexes mainly sit (84.7%), and stand quadrupedally (9.1%), males stand quadrupedally (11.5% versus 8.3%), and bipedally (2.9% versus 0.8%) more often than females. Clamber, quadrupedalism, and leap/drop are the main locomotor modes for both sexes. Rhinopithecus strykeri populations never enter canopies of degenerated secondary forest and mainly use terminal branches in the middle and upper layers of canopies in intact mid-montane moist evergreen broadleaf forest and hemlock coniferous broadleaf mixed forests across their habitat. 相似文献