Fatty acid-binding protein gene is indispensable for molting process in Heortia vitessoides(Lepidoptera:Crambidae)

As intracellular fatty acid(FA) carriers,FA-binding proteins(FABPs) widely participate in the absorption,transport,and metabolism of FAs.It is a key protein in insect lipid metabolism and plays an important role in various physiological activities of insects.An FABP gene(HvFABP) was cloned from the transcriptional library of Heortia vitessoides Moore(Lepidoptera:Crambidae),and its expression patterns were determined using reverse transcription quantitative PCR(RTqPCR).Stage-and tissue-specific expression profiles indicated that HvFABP highly expressed from prepupal to adult stages and in larval midgut and adult wings.HvFABP expression may be induced through starvation,mRNA expression was downregulated at 24 and 48 h and upregulated at 72 h after starvation.Furthermore,20-hydroxyecdysone can induce the upregulation of its expression.RNA interference-mediated silencing of Hv FABP significantly inhibited HvFABP expression,resulting in delayed development,abnormal molting or lethal phenotypes,and a significantly reduced survival rate.These results indicate that HvFABP plays a key role in the molting of H.vitessoides.

Sequencing of Intron 3 of Porcine Heart Fatty Acid-Binding Protein Gene

[ Objective] The aim of this paper is to provide the basic data for marker-assisted selection of pig breeding using porcine heart fatty acid- binding protein （H-FABP） gene. [Method] According to the related sequences of porcine H-FABP gene released in GenBank, specific primers were designed to amplify the intron 3 of porcine H-FABP gene. [ Result] The intron 3 of porcine H-FABP gene was amplified successfully. Its whole sequence was 1 350 bp in length and had been submitted to GenBank （Accession no. ： DQ 002993）. [Condusion] The study lays a theoretical foundation for determination of the major genes affecting intramuscular fat deposition.

Evaluation on performance of MM/PBSA in nucleic acid-protein systems

The molecular mechanics/Poisson-Boltzmann surface area(MM/PBSA) method has been widely used in predicting the binding affinity among ligands,proteins,and nucleic acids.However,the accuracy of the predicted binding energy by the standard MM/PBSA is not always good,especially in highly charged systems.In this work,we take the protein-nucleic acid complexes as an example,and showed that the use of screening electrostatic energy(instead of Coulomb electrostatic energy) in molecular mechanics can greatly improve the performance of MM/PBSA.In particular,the Pearson correlation coefficient of dataset Ⅱ in the modified MM/PBSA(i.e.,screening MM/PBSA) is about 0.52,much better than that(<0.33)in the standard MM/PBSA.Further,we also evaluate the effect of solute dielectric constant and salt concentration on the performance of the screening MM/PBSA.The present study highlights the potential power of the screening MM/PBSA for predicting the binding energy in highly charged bio-systems.

Effects of 4PU-30 on leaf senescence and degration of protein and nucleic acid in rice

4PU—30[N—phenyl—’N—(2—chloro—4—pyridyl) urea] is a new type of plant growth regulator with cytokinin properties. It has been confirmed to delay rice leaf senescence effectively. In order to elucidate the physiological role of 4PU—30 in delaying senescence, the changes of protein, nucleic acid contents, and the related activities of degradative enzymes were studied. Shanyou 63, an indica hybrid rice was used for this experiment. In the in vitro experiment, two full—developed leaves from the top during heading stage were collected and cut into 5.0cm segments, They were floated on the surface of distilled water containing 0.1mg/14PU—30 and incubated in darkness at 30 C. The leaves floated on distilled water were used as control.It was observed that chlorophyll content in controlled leaves declined rapidly started from the second day and dropped by 93.4% on the 6th day while that in leaves treated with 4PU—30 declined by 41.4% only. During senescence, specific activities of hemoglobin—digesting

Cold Acclimation-Induced Changes in Total Soluble Protein, RNA, DNA, RNase and Freezing Resistance in Populus tomentosa Cuttings

The changes in the contents of total soluble protein and RNA, the activity of RNase in leaves and branches of Populus tomentosa cuttings at various periods (viz: cold acclimation, deacclimation, chilling stress and the recovery after chilling stress), and the survival rate and the freezing resistance of cuttings during cold acclimation at -3℃ were investigated. Results showed that cold acclimation not only increased the contents of total soluble protein and RNA, the survival rates and the freezing resistance of cuttings, decreased the activity of RNase, but also reduced the declining degree of total soluble protein and RNA contents, and the increasing level of RNase caused by chilling stress as compared with the controls. In addition, cold acclimation augmented the increase in the level of total soluble protein and RNA, and facilitated the decrease of RNase during the recovery periods. Further analysis found that the DNA content of all treatments kept relative stability at various periods. The changes in total soluble protein, RNA and RNase were closely related to the freezing resistance of cuttings. It appears that the increase of RNA content caused by cold acclimation induced decrease of RNase activity may be involved in the accumulation of total soluble protein and the induction of freezing resistance of cuttings.

Role of Heart-Type Fatty Acid Binding Protein in Early Detection of Acute Myocardial Infarction in Comparison with cTnI, CK-MB and Myoglobin

Heart fatty acid-binding protein (H-FABP) is supposed to be the most sensitive biomarker of early acute myocardial infarction (AMI). To evaluate the diagnostic value of H-FABP for AMI in the early stage, the plasma levels of H-FABP were measured by sandwich ELISA in 93 patients with suspected AMI at admission within 6 h after onset of chest pain and 69 normal healthy subjects. The plasma concentrations of cardiac troponin-I (cTnI), creatine kinase-MB (CK-MB) and myoglobin (Mb) were assayed at the same time by using corpuscle chemiluminescence for those patients. The patients were classified as AMI group (n=32) and non-AMI group (n=61) retrospectively. The diagnostic validity was evaluated in terms of sensitivity, specificity and receiver operating characteristic (ROC) curve analysis. The results showed the cutoff value of H-FABP for AMI was 16.8 ng/ml, and its diagnostic sensitivity for AMI was 64.29 % within 3 h and 84.38 % within 6 h after onset of chest pain, and the diagnostic specificity for non-AMI was 100 % within 3 h and 91.8 % within 6 h. H-FABP had higher sensitivity than that of cTnI and CK-MB at all time points (P<0.05), whereas there was no significant difference in specificity among the four markers. But the area under the ROC curve of H-FABP was significantly greater than that of cTnI, CK-MB and Mb within 3 h. These results revealed that H-FABP possessed high diagnostic sensitivity and specificity for AMI in early stage, especially within 3 h after onset of persistent angina pectoris. In conclusion, H-FABP can be used as a sensitive marker for AMI in the early stage.

Nimbolide inhibits tumor growth by restoring hepatic tight junction protein expression and reduced inflammation in an experimental hepatocarcinogenesis

BACKGROUND Altered tight junction(TJ)proteins are correlated with carcinogenesis and tumor development.Nimbolide is a tetranotriterpenoid that has been shown to have antioxidant and anti-proliferative properties;however,its anticancer effects and molecular mechanism in hepatocellular carcinoma(HCC)remains obscure.AIM To investigate the effect of nimbolide on TJ proteins,cell cycle progression,and hepatic inflammation in a mouse model of HCC.METHODS HCC was induced in male Swiss albino mice(CD-1 strain)by a single intraperitoneal injection of 100 mg/kg diethylnitrosamine(DEN)followed by 80 ppm N-nitrosomorpholine(NMOR)in drinking water for 28 wk.After 28 wk,nimbolide(6 mg/kg)was given orally for four consecutive weeks in DEN/NMOR induced HCC mice.At the end of the 32nd week,all the mice were sacrificed and blood and liver samples were collected for various analyses.Macroscopic examinations of hepatic nodules were assessed.Liver histology and HCC tumor markers such as alpha-fetoprotein(AFP)and glypican-3 were measured.Expression of TJ proteins,cell proliferation,and cell cycle markers,inflammatory markers,and oxidative stress markers were analyzed.In silico analysis was performed to confirm the binding and modulatory effect of nimbolide on zonula occludens 1(ZO-1),nuclear factor of kappa light polypeptide gene enhancer in B-cells(NF-κB),and tumor necrosis factor alpha(TNF-α).RESULTS We found nimbolide treatment at a concentration of 6 mg/kg to HCC mice reduced hepatic tumor size by 52.08%and tumor volume(P<0.01),and delayed tumor growth in HCC mice with a concomitant reduction in tumor markers such as AFP levels(P<0.01)and glypican-3 expression(P<0.05).Furthermore,nimbolide treatment increased tight junction proteins such as ZO-1 and occludin expression(P<0.05,respectively)and reduced ZO-1 associated nucleic acid binding protein expression(P<0.001)in HCC mice liver.Nimbolide treatment to HCC mice also inhibited cell proliferation and suppressed cell cycle progression by attenuating proliferating cell nuclear antigen(P<0.01),cyclin dependent kinase(P<0.05),and CyclinD1(P<0.05)expression.In addition,nimbolide treatment to HCC mice ameliorated hepatic inflammation by reducing NF-κB,interleukin 1 beta and TNF-αexpression(P<0.05,respectively)and abrogated oxidative stress by attenuating 4-hydroxynonenal expression(P<0.01).Molecular docking studies further confirmed that nimbolide interacts with ZO-1,NF-κB,and TNF-α.CONCLUSION Our current study showed for the first time that nimbolide exhibits anticancer effect by reducing tumor size,tumor burden and by suppressing cell cycle progression in HCC mice.Furthermore,nimbolide treatment to HCC mice ameliorated inflammation and oxidative stress,and improved TJ proteins expression.Consequently,nimbolide could be potentially used as a natural therapeutic agent for HCC treatment,however further human studies are warranted.

Ultrasensitive detection of DNA and protein markers in cancer cells

Cancer cells differ from normal cells in various parameters, and these differences are caused by genomic mutations and consequential altered gene expression. The genetic and functional heterogeneity of tumor cells is a major challenge in cancer research, detection, and effective treatment. As such, the use of diagnostic methods is important to reveal this heterogeneity at the single-cell level. Droplet microfluidic devices are effective tools that provide exceptional sensitivity for analyzing single cells and molecules. In this review, we highlight two novel methods that employ droplet microfluidics for ultrasensitive detection of nucleic acids and protein markers in cancer cells. We also discuss the future practical applications of these methods.

ICP-MS在生物医学领域中的应用进展

电感耦合等离子体质谱(ICP-MS)是一种强大的痕量、超痕量元素和同位素分析仪器,具有干扰少、检出限低、分辨率高、检测速度快、多元素同时分析等优势而被广泛应用于生物医学领域。本文简要概述了近年来基于元素标记策略的ICP-MS方法和(或)ICP-MS联用技术在核酸、蛋白质定量检测以及其它与人体健康和疾病相关元素测定的进展。针对目前存在的问题给出了可行建议,并对ICP-MS的发展前景做出了展望。

CRISPR/Cas12a技术在动物疫病检测方面的应用

CRISPR/Cas系统是由簇状规则间隔的短回文重复序列(CRISPR)和CRISPR相关蛋白(Cas)组成的一种基因编辑技术,可以特异地切割和识别靶标核酸基因。该技术具有检测速度快、灵敏度高和特异性强的优势,因此被广泛应用于动物疫病检测领域。本文就CRISPR/Cas12a结合等温核酸扩增技术和可视化技术在动物疫病检测中的应用进行综述,并对其应用前景进行展望,以期为我国的养殖业和进境动物疫病的监测提供技术支撑。

金黄色葡萄球菌耐药机制及治疗药物

金黄色葡萄球菌(Staphylococcus aureus)是引起局部化脓和心内膜炎等多种感染的重要人兽共患革兰阳性病原菌。其传播速度快,致病力强,且耐药性日益严重,给全球公共卫生安全和动物养殖业造成了巨大威胁。这对深入了解金黄色葡萄球菌耐药机制以及药物新靶点的开发提出了迫切需求。因此,本文对当前临床使用的抗生素的作用机制和耐药机理进行了综述,并特别关注了相关领域的最新研究进展,以期望为临床防治细菌耐药和新药研制提供新的视角和参考。

CRISPR/Cas核酸检测系统的研究进展和未来挑战

成簇规律间隔短回文重复序列(CRISPR)/成簇规律间隔短回文重复序列相关蛋白(Cas)系统是一种新兴的分子诊断技术,具有检测速度快、操作简单、特异性高等优势,目前已成为分子诊断领域的研究热点。基于CRISPR/Cas系统构建的核酸检测系统中有一部分已得到临床验证,并获得预期的结果,有望成为一种理想的核酸分子诊断技术,但其在临床大规模应用前尚有一系列问题需要解决。文章对已建立的CRISPR/Cas核酸检测系统的原理、特点和存在的问题进行综述,以期为CRISPR/Cas核酸检测系统的临床应用提供依据。

Histone Deacetylase Inhibitor SAHA Induces Expression of Fatty Acid-Binding Protein 4 and Inhibits Replication of Human Cytomegalovirus

Suberoylanilide hydroxamic acid(SAHA) is a histone deacetylase inhibitor that shows marked efficacy against many types of cancers and is approved to treat severe metastatic cutaneous T-cell lymphomas. In addition to its anticancer activity,SAHA has significant effects on the growth of many viruses. The effect of SAHA on replication of human cytomegalovirus(HCMV) has not, however, been investigated. Here, we showed that the replication of HCMV was significantly suppressed by treatment with SAHA at concentrations that did not show appreciable cytotoxicity. SAHA reduced transcription and protein levels of HCMV immediate early genes, showing that SAHA acts at an early stage in the viral life-cycle. RNAsequencing data mining showed that numerous pathways and molecules were affected by SAHA. Interferon-mediated immunity was one of the most relevant pathways in the RNA-sequencing data, and we confirmed that SAHA inhibits HCMV-induced IFN-mediated immune responses using quantitative Real-time PCR(qRT-PCR). Fatty acid-binding protein 4(FABP4), which plays a role in lipid metabolism, was identified by RNA-sequencing. We found that FABP4 expression was reduced by HCMV infection but increased by treatment with SAHA. We then showed that knockdown of FABP4 partially rescued the effect of SAHA on HCMV replication. Our data suggest that FABP4 contributes to the inhibitory effect of SAHA on HCMV replication.

核酸条形码技术:扩展蛋白质-蛋白质相互作用检测通量的新方法

蛋白质-蛋白质相互作用(protein-protein interaction,PPI)几乎参与了机体内所有重要的生物学过程,在细胞的基本生命过程中扮演了至关重要的角色,开发高通量的PPI检测新方法具有重要的生物学意义。目前,下一代测序技术(next-generation sequencing,NGS)发展快速,能在几天内测定超过10亿个模板的DNA序列。由于并行DNA测序技术所特有的敏感性、特异性、高通量和多路复用优势,其已被用作广谱分子计数器,应用于基因组测序和转录物组测序等领域。核酸条形码技术通过将寡核苷酸标签与目标蛋白质连接起来,从而标记编码蛋白质。之后,利用高通量的测序方法检测相互作用的蛋白质,实现了PPI的高通量检测。这一技术推动了PPI检测方法的飞速发展,提升了单次实验检测的通量,为构建PPI网络提供了强有力的技术支持。本文详细阐述了核酸条形码在PPI检测方法中的设计、生成和读取;通过分析核酸条形码技术在PPI研究中的应用范例,探讨了各自的优势和不足,并评估了数据的可靠性,讨论了基于核酸条形码技术的PPI检测方法未来的发展趋势。

细胞外囊泡分析方法

细胞外囊泡携带核酸、蛋白质和脂质等生物分子,在细胞间通讯中发挥着重要作用,与多种疾病的发生与发展密切相关。细胞外囊泡广泛分布于大多数体液中,是液体活检的有效生物标志物之一,可用于非侵入性疾病早期诊断和疗效监测。因此,细胞外囊泡及其携带生物分子(蛋白质、核酸)的分析与研究受到了广泛关注。研究者们基于抗体或核酸适配体特异性识别细胞外囊泡表面蛋白质,提出了多种策略用于细胞外囊泡及其表面蛋白质的高灵敏、高特异性检测。采用直接递送或膜融合方式将传感探针输送至细胞外囊泡内部,可实现细胞外囊泡内部核酸的原位、准确检测。本文综述了细胞外囊泡及其携带生物分子检测方法的最新进展,并展望了该领域未来的发展方向。

结直肠癌组织中DJ-1表达对患者区域淋巴结转移及预后的临床意义

目的 分析结直肠癌(CRC)组织中蛋白/核酸去糖酶1(DJ-1)表达与患者区域淋巴结转移(LNM)及预后的相关性。方法 选择2017年6月至2022年4月在桂林市人民医院接受根治性手术的258例CRC患者作为研究对象,收集了258例患者的CRC组织,其中81例患者有配对的癌旁组织。另选择同期经内镜下治疗的58例患者的结直肠腺瘤组织作为对照。分析CRC组织中不同DJ-1蛋白表达与患者临床病理特征的关系。采用免疫组织化学法分析组织中DJ-1表达情况。采用多因素logistic回归分析探讨区域LNM的预测因素。采用单因素和多因素Cox回归分析探讨影响CRC患者复发及死亡的因素。采用Kaplan-Meier生存曲线分析不同DJ-1表达患者的5年无复发生存率和生存率。结果 3组的DJ-1蛋白表达差异有统计学意义(χ^(2)=202.557,P<0.001)。CRC组织中DJ-1蛋白中度表达和强表达患者的占比均显著高于癌旁组织和结直肠腺瘤组织(P均<0.05)。高表达组患者的年龄偏大,55.56%患者的原发病灶位于左半结肠,低分化CRC患者的占比较高,患者的区域LNM阳性率也较高(P均<0.05)。多因素logistic回归分析结果显示,CRC组织中DJ-1蛋白高表达能独立预测区域LNM和低分化CRC(P均<0.05)。258例患者的5年无复发生存率和生存率分别67.44%和70.54%。单因素和多因素Cox回归分析结果显示,CRC组织中DJ-1蛋白高表达为CRC患者复发和死亡的独立危险因素(P均<0.05)。上述结果与基于Oncomine数据库和TCGA队列的生物信息学分析结果基本一致。结论 CRC组织中DJ-1蛋白高表达与区域LNM相关,这可能是患者预后的影响因素。DJ-1有潜力成为预测CRC患者区域LNM和预后的生物标志物。

A possible mode of the specific recognition of nucleic acids by proteins

Seven sets of protein target sites, which occur in several gene promoters, have been analyzed. The results suggest that there is a possible mode of specific recognition of double-helical nucleic acids by proteins. This recognition mode is related to a special topological property of double-helical DNA, which is termed base spatial pattern (BSP) of DNA segment. BSP is the spatial topological property determined only by the spatial arrangement of the bases on double-helical DNA segment.

CRISPR-Cas系统在食源性致病菌检测中的研究进展

食源性致病菌的快速检测对预防食源性疾病的爆发具有重要意义。成簇规律间隔短回文重复序列(clustered regularly interspaced short palindromicrepeats,CRISPR)及CRISPR相关蛋白(CRISPR-associated protein,Cas)构成的CRISPR-Cas系统已被广泛的应用于核酸检测,并在对食源性致病菌的检测中展现出快速、灵敏度高、特异性强等优势。本文介绍了CRISPR-Cas系统的原理、机制,总结了CRISPR-Cas系统与不同扩增方法和信号输出模式相结合在食源性致病菌检测中的应用,并讨论了这些检测方法存在的一些问题和挑战,最后对该技术的未来发展前景进行展望,旨在为食源性致病菌的快速检测提供新思路。

反式切割CRISPR/Cas技术在食源致病微生物检测方面的原理及应用

食源性致病微生物是食品安全的一大严重威胁,传统的生化检测手段面临着一系列挑战。近年来,随着成簇规律间隔短回文重复序列(clustered regularly interspaced short palindromic repeats,CRISPR)技术的逐步发展,具有反式切割活性的CRISPR/Cas体系受到了越来越多的关注。本文综述了具有反式切割活性的CRISPR/Cas体系的起源与分类,并详细介绍了具有反式切割活性的CRISPR/Cas体系的作用原理。同时,本文对反式切割CRISPR/Cas技术在食源性致病微生物领域的多方面应用进行了综述,并讨论了该技术的优劣和未来发展方向。

QCM传感器在生物医学检测中的应用研究进展

现代医学在治疗技术和药物研发不断提升的同时,也越来越依赖于医学检测技术的进步。石英晶体微天平(quartz crystal microbalance,QCM)是基于石英晶体压电效应的一种新型高灵敏的纳克级质量型传感技术,具有实时监测、高灵敏度、免标记等优势,近年在生物医学检测领域中广泛应用。该文概述了近年来QCM传感器的构建及其在核酸、蛋白质、癌细胞和微生物检测中的应用研究进展,并对其未来的发展方向进行探讨。