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1.
Lipid nanoparticles (LNPs) are becoming popular as a means of delivering therapeutics, including those based on nucleic acids and mRNA. The mRNA-based coronavirus disease 2019 vaccines are perfect examples to highlight the role played by drug delivery systems in advancing human health. The fundamentals of LNPs for the delivery of nucleic acid- and mRNA-based therapeutics, are well established. Thus, future research on LNPs will focus on addressing the following: expanding the scope of drug delivery to different constituents of the human body, expanding the number of diseases that can be targeted, and studying the change in the pharmacokinetics of LNPs under physiological and pathological conditions. This review article provides an overview of recent advances aimed at expanding the application of LNPs, focusing on the pharmacokinetics and advantages of LNPs. In addition, analytical techniques, library construction and screening, rational design, active targeting, and applicability to gene editing therapy have also been discussed.  相似文献   
2.
【摘要】目的 探讨二维斑点追踪显像技术(2D-STI)评估新生儿窒息合并心肌损害后左心室整体及局部心肌的纵向收缩功能在早期诊断窒息新生儿心肌损害中的临床价值。方法 选择2019年07月至2020年12月期间在右江民族医学院附属医院新生儿科住院的足月窒息新生儿61例,经临床确诊合并心肌损害,根据Apgar评分分为轻度组31例和重度组30例,选择同期住院出生的正常足月新生儿30例作为对照组。检测受检者的血清肌酸激酶同工酶(CK-MB)、肌钙蛋白(cTnT)、左室舒张期前后径(LVDId)、左室射血分数(LVEF)、左室短轴缩短率(LVFS)、辛普森法左室射血分数(Simpson EF)、左室三腔心整体应变(GLS-LAX)、左室四腔心整体应变(GLS-A4C)、左室两腔心整体应变(GLS-A2C)、左室整体应变(GLS-AVG),分析GLS-AVG和CK-MB、cTnT三者的相关性。结果 三组间CK-MB和cTnT比较差异有统计学意义(P<0.05)。三组间性别、体重、胎龄均无统计学差异(P>0.05)。三组间LVDId、LVEF、LVFS、Simpson EF比较差异无统计学意义(P>0.05)。GLS-AVG与CK-MB呈负性相关(r=-0.515,P=0.000),GLS-AVG与cTnT呈负性相关(r=-0.912,P=0.000)。结论 GLS-AVG与CK-MB、cTnT具有相关性,GLS-AVG可作为窒息新生儿心肌损害早期诊断指标。  相似文献   
3.
DNA损伤应答(DNA damage response,DDR)缺陷是近年来乳腺癌治疗研究的热门靶点之一。DDR通路负责DNA损伤后的识别、信号转导和修复,其功能异常可导致细胞的凋亡或基因组不稳定性的增加。目前进入临床研究阶段的乳腺癌DDR靶向药物主要包括多聚腺苷二磷酸核糖聚合酶[poly (ADP-ribose) polymerase,PARP]抑制剂、ATM抑制剂、CHEK1抑制剂、ATR抑制剂及WEE1抑制剂等。主要从DDR缺陷的概念、以DDR作为靶点的基本原理、DDR各类靶向药物的临床研究现状及其在临床应用中的难点与挑战等方面展开综述。  相似文献   
4.
《Cancer cell》2021,39(9):1214-1226.e10
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5.
Increasing trend in oral cancer (0.6% per year) and its related mortality has been reported worldwide since 2010. The United States alone reports an increase of 57% within the past 10 years. This emphasizes the need not only for designing strategies of prevention and planning but also for an effective treatment regime for the various oral cancers. Cancers of the lips, tongue, cheeks, floor of the mouth, and hard palate have been primarily classified under the category of oral cancers. If left undiagnosed, these cancers can be life threatening. Amongst these, the most undesignated and understudied cancer type is the lip carcinoma, which is either categorized under oral cancer or/as well as skin cancer or head and neck cancer. However, lip cancer corresponds to 25–30% of all diagnosed oral cancers. Though the etiology of lip cancer is not yet fully understood, numerous risk factors involved in its development are now being studied. The cells in the lip region are continuously exposed to various DNA damaging agents from endogenous as well as exogenous sources. Flaws in DNA repair mechanisms involved in eliminating these damages may be linked to the origin of carcinogenesis. Accumulation of DNA damage and defect in repair mechanisms may play a role in lip carcinogenesis and progression. This literature review is an exhaustive compilation of the research work performed on the role of DNA damage and repair responses in lip carcinoma which will pave a path for researchers to identify predictive DNA repair biomarker/s for lip cancer, and its diagnosis, prevention, and treatment.  相似文献   
6.
【摘要】 目的 明确1个LEOPARD综合征家系的PTPN11基因突变。方法 对中国科学院大学宁波华美医院确诊的1例LEOPARD综合征先证者的家系进行现场调查。提取家系内4例患者、2例健康成员及与该家系无关的100例健康对照外周血标本。PCR扩增PTPN11基因所有外显子,使用Sanger测序法进行突变位点分析。结果 该家系3代14人,其中6人患病(男3例,女3例),符合常染色体显性遗传。患者皮损主要分布于面部、躯干和四肢,具有特殊面容及心血管系统异常。4例患者存在PTPN11基因的错义突变c.1632G>T(p.R558L),导致第558位由精氨酸变为亮氨酸,该突变既往未曾报道。该家系2例健康成员及100例健康对照未发现PTPN11基因突变。结论 该LEOPARD综合征家系患者PTPN11基因13号外显子发生c.1632G>T错义突变,可能是该家系患者发病的分子基础。  相似文献   
7.
The WJOG8815L phase II clinical study involves patients with non‐small cell lung cancer (NSCLC) that harbored the EGFR T790M mutation, which confers resistance to EGFR tyrosine kinase inhibitors (TKIs). The purpose of this study was to assess the predictive value of monitoring EGFR genomic alterations in circulating tumor DNA (ctDNA) from patients with NSCLC that undergo treatment with the third‐generation EGFR‐TKI osimertinib. Plasma samples of 52 patients harboring the EGFR T790M mutation were obtained pretreatment (Pre), on day 1 of treatment cycle 4 (C4) or cycle 9 (C9), and at diagnosis of disease progression or treatment discontinuation (PD/stop). CtDNA was screened for EGFR‐TKI‐sensitizing mutations, the EGFR T790M mutation, and other genomic alterations using the cobas EGFR Mutation Test v2 (cobas), droplet digital PCR (ddPCR), and targeted deep sequencing. Analysis of the sensitizing—and T790M—EGFR mutant fractions (MFs) was used to determine tumor mutational burden. Both MFs were found to decrease during treatment, whereas rebound of the sensitizing EGFR MF was observed at PD/stop, suggesting that osimertinib targeted both T790M mutation‐positive tumors and tumors with sensitizing EGFR mutations. Significant differences in the response rates and progression‐free survival were observed between the sensitizing EGFR MF‐high and sensitizing EGFR MF‐low groups (cutoff: median) at C4. In conclusion, ctDNA monitoring for sensitizing EGFR mutations at C4 is suitable for predicting the treatment outcomes in NSCLC patients receiving osimertinib (Clinical Trial Registration No.: UMIN000022076).

Abbreviations

CIs
confidence intervals
ctDNA
circulating tumor DNA
ddPCR
droplet digital PCR
EGFR
epidermal growth factor receptor
MFs
mutant fractions
NGS
next‐generation sequencing
NSCLC
non‐small cell lung cancer
ORR
overall response rate
OS
overall survival
PD
progressive disease
PFS
progression‐free survival
PR
partial response
SD
stable disease
TKI
tyrosine kinase inhibitor
  相似文献   
8.
Background and aimsIncreased alcohol consumption has been associated with CVD risk. Subclinical arterial damage (SAD) precedes the onset of cardiovascular disease (CVD), and allows early identification and study of the pathophysiology of CVD. Reliable, noninvasive vascular biomarkers are available for the early detection of SAD and reclassification of CVD risk. To investigate the association of alcohol consumption with multiple SAD biomarkers and central hemodynamics in a large sample of Greek adults with CVD risk factors.Methods and resultsThis cross-sectional study was conducted with 938 participants (43.5% men) and collected data on SAD biomarkers, central hemodynamics, and dietary intake. Multiple linear regression analysis was performed according to sex after adjusting for several confounders. In men, alcohol consumption of 20–30 g/d was positively associated with mean, diastolic, and peripheral systolic blood pressure (BP). The consumption of >30 g/d was positively associated with the augmentation index. In women, no statistically significant associations were found between alcohol consumption and BP or SAD indices. No statistically significant associations were found between alcohol consumption and arterial compliance or distensibility in both sexes.ConclusionIn men even a small deviation from the current recommendation for alcohol consumption is associated with both higher BP indices and pressure wave reflections. The absence of association in women might be due to very low alcohol intake, even in the high consumption group. More studies are needed to verify our findings and establish the above associations in each sex.  相似文献   
9.
Skin cancer is the deadliest type of malignant disease and causes primary mortality worldwide. Dioscin, which exists in medicinal plants, has potent anticancer effects. However, its effects on skin cancer remain unknown. In the present study, the activity and mechanism of dioscin on the human skin cancer A431 cell line were investigated, MTT, colony formation, Transwell, wound-healing, TUNEL, Comet, immunofluorescence and western blot assays were used to assess the effects of dioscin on A431 cells. The results of MTT, colony formation, Transwell and wound-healing assays revealed that dioscin suppressed proliferation, colony formation and invasion of the cancer cells. TUNEL and comet assays demonstrated that dioscin exhibited significant effects on cell apoptosis and DNA damage. Investigations into the mechanism revealed that the expression levels of phosphorylated Ataxia telangiectasia-mutated (ATM) were considerably activated by dioscin, which significantly upregulated the expression levels of p53 to activate mitochondrial apoptosis signaling. Furthermore, the expression levels of BAX, cleaved caspase-3/9 and cleaved poly (ADP-ribose) polymerase were upregulated, and the expression levels of BCL-2 were downregulated by dioscin. Additionally, dioscin markedly downregulated the expression levels of matrix metalloproteinase 2 (MMP2), MMP9, RHO and cdc42, which are all associated with tumor invasion. In addition, p53-small interfering RNA transfection experiments indicated that dioscin exhibited excellent activity against skin cancer in vitro by decreasing p53 expression. Overall, the present results suggested that dioscin inhibited skin cancer cell proliferation via adjusting ATM/p53-mediated cell apoptosis, migration and DNA damage, which should be considered as a potential option for future treatments of skin cancer.  相似文献   
10.
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