Lipoprotein(a) and Atherosclerotic Cardiovascular Disease: Current Understanding and Future Perspectives.

PURPOSE: To review current knowledge of elevated lipoprotein(a) [Lp(a)] levels in relation to atherosclerotic cardiovascular disease (ASCVD) and discuss their potential use as biomarkers and therapeutic approaches in clinical practice. METHODS: We summarized the current understanding and recent advances in the structure, metabolism, atherogenic mechanisms, standardized laboratory measurement, recommended screening populations, and prognostic value of Lp(a), with a special focus on the current potential treatment approaches for hyperlipoprotein(a)emia in patients with ASCVD. RESULTS: Lp(a) is composed of LDL-like particle and characteristic apolipoprotein(a) [apo(a)] connected by a disulfide bond. Substantial evidence shows that elevated plasma Lp(a) level is a heritable, independent, and possibly causal risk factor for ASCVD through its proatherogenic, proinflammatory, and potentially prothrombotic properties. Current guidelines recommend Lp(a) measurement for patients with an intermediate-high risk of ASCVD, familial hypercholesterolemia, a family history of early ASCVD or elevated Lp(a), and progressive ASCVD despite receiving optimal therapy. Traditional Lp(a)-lowering approaches such as niacin, PCSK9 inhibitors, mipomersen, lomitapide, and lipoprotein apheresis were associated with a non-specific and limited reduction of Lp(a), intolerable side effects, invasive procedure, and high expense. The phase 2 randomized controlled trial of antisense oligonucleotide against the apo(a) encoding gene LPA mRNA showed that IONIS-APO(a)-LRX could specifically reduce the level of Lp(a) by 90% with good tolerance, which may become a promising candidate for the prevention and treatment of ASCVD in the future. CONCLUSIONS: It is reasonable to measure Lp(a) levels to reclassify ASCVD risk and manage individuals with elevated Lp(a) to further reduce the residual risk of ASCVD, especially with IONIS-APO(a)-LRX.

Effects of TiO2 nanoparticles on nutrition metabolism in silkworm fat body.

Silkworm (Bombyx mori) is an important economic insect with a fat body that plays a crucial role in the storage and transfer of nutrients. It is also known that TiO2 nanoparticles (NPs) can improve feed efficiency and promote silk protein synthesis in the silkworm. In this study, we profiled gene expression in the silkworm fat body after TiO2 NP treatment, validated the major RNA-seq findings, and determined the contents of trehalose and triglyceride, the activity of lipase, and the amount of total proteins. RNA-seq analysis revealed that TiO2 NP treatment caused significant expression changes in 341 genes (P≤0.01), 138 of which were upregulated while the other 203 were downregulated. The expression levels of two target genes in the insulin signaling pathway and two protein metabolism-related target genes, three lipid metabolism-associated target genes, two carbohydrate metabolism related target genes and expression levels of seven heat shock protein genes were increased, and that of threonine dehydratase gene and fatty acid transport protein gene were decreased. The RNA-seq results of 16 genes were validated by quantitative real-time PCR. The lipase activity, content of trehalose, and amount of total proteins were elevated by 3.86-fold, 1.34-fold, and 1.21-fold, respectively, and the content of triglyceride was decreased by 0.94-fold after TiO2 NP treatment. These results indicated that TiO2 NPs activated the insulin signaling pathway, promoted the metabolism of protein, fat, and carbohydrate, and improved nutrition metabolism. Our study provides new support for the understanding of the beneficial effect of TiO2 NPs on silkworm nutrient metabolism.

Effects of mutations on the structure and function of silkworm type 1 acetylcholinesterase.

AChE is the target of organophosphate (OP) and carbamate (CB) pesticides, and mutations in the gene can significantly reduce insects' sensitivity to these pesticides. Bombyx mori is highly sensitive to pesticides. To investigate the effects of mutations on AChE1 structure and function, we used a prokaryotic system to express B.mori wild type AChE1 (wAChE1) and mutant AChE1 (mAChE1) in this study. Active AChE1 proteins were obtained after refolding and purification, and wAChE1 and mAChE1 had similar activities. After incubation with 10(-6)M physostigmine and 10(-3)mg/mL phoxim, the remaining enzyme activity of mAChE1 was 4.42% and 8.86% higher than that of wAChE1's, respectively. Three-dimensional analysis of mutation AChE1 (mAChE1) revealed that the Ser and Ala side chains extended toward the central part of S285 with distances of just 2.80Å and 3.68Å, respectively, which changed the spatial structure of the active center and reduced its sensitivity to pesticides. These results indicated that the mutations altered the 3D structure of AChE1, which may affect the binding of physostigmine and phoxim to the serine residue at the active center, leading to reduced sensitivity. Our study helps understand the relationship between AChE1 mutations and pesticide resistance and provides a new direction for the cultivation of new pesticide-resistant varieties of B.mori.

Mechanisms of TiO2 NPs-induced phoxim metabolism in silkworm (Bombyx mori) fat body.

Silkworm is an important economic insect. Abuse of organophosphorus pesticides in recent years often leads to poisoning of silkworms, which significantly affects sericulture development by reducing silk production. Previous studies have shown that TiO2 NPs can effectively mitigate the damages caused by organophosphorus pesticides in silk glands and nerve tissues. The fat body is an important metabolic detoxification organ of silkworms, but it is unknown whether TiO2 NPs affect pesticide metabolism in fat body. In this study, we characterized the transcription of antioxidant genes and enzyme activity in fat body after TiO2 NPs and phoxim treatments using transcriptome sequencing, real-time PCR, and enzyme activity assay. Transcriptome sequencing detected 10 720, 10 641, 10 403, and 10 489 genes for control group, TiO2 NPs group, phoxim group, and TiO2 NPs+phoxim group, respectively. The TiO2 NPs+phoxim group had 705 genes with significantly differential expression (FDR<0.001), among which the antioxidant genes thioredoxin reductase 1 and glutathione S-transferase omega 3 were significantly upregulated. In phoxim group, the expression levels of superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase delta (GSTd), and thioredoxin peroxidase (TPx) were increased by 1.365 -fold, 1.335 -fold, 1.642 -fold, and 1.765 -fold, respectively. The level changes of SOD, CAT, GSTd, and TPx were validated by real time PCR. The contents of reactive oxygen species (ROS), malondialdehyde (MDA), and hydrogen peroxide (H2O2) were increased by 1.598 -fold, 1.946 -fold, and 1.506 -fold, respectively, indicating that TiO2 NPs treatment can relieve phoxim-induced oxidative stress. To clarify the mechanism of TiO2 NPs's effect, the transcription levels of P450 gene family were measured for the TiO2 NPs+phoxim group; the expression levels of CYP4M5, CYP6AB4, CYP6A8, and CYP9G3 were elevated by 2.784 -fold, 3.047 -fold, 2.254 -fold, and 4.253 -fold, respectively, suggesting that high expression of P450 family genes can enhance the metabolism of phoxim in the fat body. The results of this study indicated that TiO2 NPs treatment promoted the transcriptional expression of the P450 family genes to improve the fat body's ability to metabolize phoxim and reduce phoxim-induced oxidative stress. This may be the main mechanism of TiO2 NPs' mitigation of phoxim-induced damages in the fat body.

Differentially expressed genes in the fat body of Bombyx mori in response to phoxim insecticide.

The silkworm, Bombyx mori, is an economically important insect. However, poisoning of silkworms by organophosphate pesticides causes tremendous loss to the sericulture. The fat body is the major tissue involved in detoxification and produces antimicrobial peptides and regulates hormones. In this study, a microarray system comprising 22,987 oligonucluotide 70-mer probes was employed to examine differentially expressed genes in the fat body of B. mori exposed to phoxim insecticide. The results showed that a total of 774 genes were differentially expressed upon phoxim exposure, including 500 up-regulated genes and 274 down-regulated genes. The expression levels of eight detoxification-related genes were up-regulated upon phoxim exposure, including six cytochrome P450s and two glutathione-S-transferases. It was firstly found that eight antimicrobial peptide genes were down-regulated, which might provide important references for studying the larvae of B. mori become more susceptible to microbial infections after phoxim treatment. In addition, we firstly detected the expression level of metamorphosis-related genes after phoxim exposure, which may lead to impacted reproduction. Our results may facilitate the overall understanding of the molecular mechanism of multiple pathways following exposure to phoxim insecticide in the fat body of B. mori.

Characteristics of phoxim-exposed gene transcription in the silk gland of silkworms.

Silkworm (Bombyx mori), a model Lepidoptera insect, is an important economic insect. Its silk gland is the important organ for silk protein synthesis and secretion. Phoxim exposure causes deficient cocooning of silkworm and has become one of the major negative factors for the silk industry. To study the impact of phoxim exposure on silk gland, using gene chip technology, we examined differentially expressed genes in silk gland after silkworms were exposed to phoxim (4.0µg/mL) for 24h. Functional annotation, classification and KEGG signaling pathway analysis were performed. The results showed that out of 3206 genes detected in silk gland after phoxim exposure, 270 were differentially expressed significantly, including 249 up-regulated genes and 21 down-regulated genes. These differentially expressed genes related to apoptosis, detoxification and protein degradation were selected. Using qRT-PCR, the expression levels of 9 genes involved in apoptosis, detoxification and protein degradation were validated. In addition, the expression profiles of three related fibroin synthesis genes (Fib-H, Fib-L and P25) were analyzed. Our results showed that phoxim exposure induced apoptosis of silk gland cells and inhibition of fibroin synthesis. This may be the cause of deficient silkworm cocooning.

Endosperm-specific hypomethylation, and meiotic inheritance and variation of DNA methylation level and pattern in sorghum (Sorghum bicolor L.) inter-strain hybrids.

Understanding dynamics and inheritance of DNA methylation represents important facets for elucidating epigenetic paradigms in plant development and evolution. Using four sets of sorghum (Sorghum bicolor L.) inter-strain hybrids and their inbred parents, the developmental stability and inheritance of cytosine methylation in two tissues, leaf and endosperm, by MSAP analysis were investigated. It was found that in all lines (inbred and hybrid) studied, endosperm exhibited a markedly reduced level of full methylation of the external cytosine or both cytosines at the CCGG sites relative to leaf, which caused a variable reduction in the estimated total methylation level in endosperm by 6.89-19.69% (11.47% on average). For both tissues, a great majority of cytosine methylation profiles transmitted to F1 hybrids, however, from 1.69 to 3.22% of the profiles showed altered patterns in hybrids. Both inherited and altered methylation profiles can be divided into distinct groups, and their frequencies are variable among the cross-combinations, and between the two tissues. The variations in methylation level and pattern detected in the hybrids were not caused by parental heterozygosity, and they could be either non-random or stochastic among hybrid individuals. Homology analysis of isolated bands that showed endosperm-specific hypomethylation or variation in hybrids indicated that diverse sequences were involved, including known-function cellular genes and mobile elements. RT-PCR analysis of six genes representing endosperm-specific hypomethylation in MSAP profiles indicated that all showed higher expression in endosperm than in leaf, suggesting involvement of methylation state in regulating tissue-specific or tissue-biased expression in sorghum. Analysis on leaf-RNA from 5-azacytidine-treated plants further corroborated this possibility.

[One stage resection of esophageal cancer and pulmonary bulla--a report of three patients].

Since 1982, three patients with esophageal cancer complicated with pulmonary bullae have been treated by operation on the esophagus and lung in one performance: In all the patients, the bullae were on the same side of the operation. The esophageal or cardiac cancer was resected first, then the bulla was treated. The site of esophago-gastric anastomosis was reinforced by the greater omentum. For mid-upper esophageal cancer, cervical anastomosis was done in order to avoid infection or leakage. In the third patient, pyopneumothorax occurred after wedge resection of a large bulla in the right upper lung and the surrounding tissues. The patient survived after timely drainage and medical management. The extent of resection for pulmonary bulla (bulla, segment or lobe) depends on the location, shape, size and number of the bullae and the pathological change in the surrounding tissues. We suggest that the indications: Cardio-pulmonary functions of the patient be stage II or better, even with mild emphysema so as they can tolerate anesthesia and surgery. Pulmonary function can be compensated after the lesion is removed, otherwise it is taken as a contraindication. The one stage removal of two foci makes it possible to avoid postoperative complications.