lncRNA LOC100911717-targeting GAP43-mediated sympathetic remodeling after myocardial infarction in rats

ObjectiveSympathetic remodeling after myocardial infarction (MI) is the primary cause of ventricular arrhythmias (VAs), leading to sudden cardiac death (SCD). M1-type macrophages are closely associated with inflammation and sympathetic remodeling after MI. Long noncoding RNAs (lncRNAs) are critical for the regulation of cardiovascular disease development. Therefore, this study aimed to identify the lncRNAs involved in MI and reveal a possible regulatory mechanism.Methods and resultsM0- and M1-type macrophages were selected for sequencing and screened for differentially expressed lncRNAs. The data revealed that lncRNA LOC100911717 was upregulated in M1-type macrophages but not in M0-type macrophages. In addition, the lncRNA LOC100911717 was upregulated in heart tissues after MI. Furthermore, an RNA pull-down assay revealed that lncRNA LOC100911717 could interact with growth-associated protein 43 (GAP43). Essentially, immunofluorescence assays and programmed electrical stimulation demonstrated that GAP43 expression was suppressed and VA incidence was reduced after lncRNA LOC100911717 knockdown in rat hearts using an adeno-associated virus.ConclusionsWe observed a novel relationship between lncRNA LOC100911717 and GAP43. After MI, lncRNA LOC100911717 was upregulated and GAP43 expression was enhanced, thus increasing the extent of sympathetic remodeling and the frequency of VA events. Consequently, silencing lncRNA LOC100911717 could reduce sympathetic remodeling and VAs

Seismic stratigraphy of the central South China Sea basin and implications for neotectonics

Coring/logging data and physical property measurements from International Ocean Discovery Program Expedition 349 are integrated with, and correlated to, reflection seismic data to map seismic sequence boundaries and facies of the central basin and neighboring regions of the South China Sea. First-order sequence boundaries are interpreted, which are Oligocene/Miocene, middle Miocene/late Miocene, Miocene/Pliocene, and Pliocene/Pleistocene boundaries. A characteristic early Pleistocene strong reflector is also identified, which marks the top of extensive carbonate-rich deposition in the southern East and Southwest Subbasins. The fossil spreading ridge and the boundary between the East and Southwest Subbasins acted as major sedimentary barriers, across which seismic facies changes sharply and cannot be easily correlated. The sharp seismic facies change along the Miocene-Pliocene boundary indicates that a dramatic regional tectonostratigraphic event occurred at about 5 Ma, coeval with the onsets of uplift of Taiwan and accelerated subsidence and transgression in the northern margin. The depocenter or the area of the highest sedimentation rate switched from the northern East Subbasin during the Miocene to the Southwest Subbasin and the area close to the fossil ridge in the southern East Subbasin in the Pleistocene. The most active faulting and vertical uplifting now occur in the southern East Subbasin, caused most likely by the active and fastest subduction/obduction in the southern segment of the Manila Trench and the collision between the northeast Palawan and the Luzon arc. Timing of magmatic intrusions and seamounts constrained by seismic stratigraphy in the central basin varies and does not show temporal pulsing in their activities.Keywords: South China Sea, Neotectonism, Core-well-seismic integration, Seismic facies, Seismic stratigraphy, IODP Expedition 34

Hydrocarbon accumulation conditions and exploration direction of Baiyun–Liwan deep water areas in the Pearl River Mouth Basin

An integrated geologic study was performed in the Baiyun–Liwan deep water areas, Pearl River Mouth Basin, based on the achievements obtained during the past five exploration stages. The following understandings were obtained. (1) The Baiyun Sag has superior source rock conditions and has experienced three tectonic evaluation stages like rifting, rifting-depression and depression. The Wenchang–Enping Fms deposited during the rifting stage have large hydrocarbon generation potentials. During the rifting-depression and depression stages, the deposition in the study area was controlled by the Oligocene and Miocene shelf slope break zones. The Oligocene Zhuhai Fm shallow marine delta-longshore depositional system and the Miocene Zhujiang–Hanjiang Fms deep fan depositional system were formed, and they are the most favorable reservoir-caprock assemblages in the study area. (2) The Hydrocarbon accumulation pattern in the deep waters is different from that in the northern shallow waters. Shelf slope break zone, composite conduction system consisting of structural ridge, fault, sandbody, unconformity and fluid diapir as well as late tectonic movement are the three major factors controlling hydrocarbon migration and accumulation in the study area. (3) The Liwan 3-1 gas field is a typical example. The superior trapping conditions, high-quality reservoirs of delta distributary channel controlled by shelf slope break zone, vertical conduction system consisting of fault and diapir, as well as the overlying massive marine mudstone caprock provide favorable geologic conditions for the formation of large gas fields. Four areas were identified as the targets of gas exploration in the near future: the deep water fan system in the central sag, the structural-stratigraphic traps in the uplifted areas on both sides of the main sag of Baiyun, a series of large structural traps on the fault terrace to the southwest of the main sag, and the ultra-deep frontiers in sags such as Liwan to the south of the main sag

Influence of Explosive Ratio on Morphological and Structural Properties of Ti/Al Clads

The current work focuses on the effect of explosive ratio R on the comprehensive properties of Ti/Al clads manufactured via explosive welding. The lower and upper limits of explosive ratio, namely R1 and R2, were determined according to the R⁻δf (flyer plate thickness) welding window. Two TA2/1060 explosive cladding plates were successfully manufactured at the different explosive ratios. Microstructure investigation was conducted by optical microscopy (OM), scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS). The small wave bonding interface was observed at R1, where the vortex structure containing the ingot structure appeared periodically. The bonding interface presented a big wave bonding morphology and a locally continuous melting layer at R2. Many prolonged grains and adiabatic shear bands (ASBs) were found near the interface for a greater explosive load. Intermetallic compounds were formed in the bonding zones of the two plates. The thickness of element diffusion area increased with an increasing explosive ratio. Comparative tests of mechanical properties indicated that the tensile shear strength at R1 was higher. The microhardness, tensile strength, and bending performance of the two plates are similar and acceptable. Tensile fracture analysis indicated the fracture mode at R1 was ductile fracture, while the explosive cladding plate at R2 had mainly ductile fracture with quasi-cleavage fracture as the supplement

Compound hydrocarbon accumulation and enrichment in southwestern Huizhou Sag, Pearl River Mouth Basin, South China Sea

Aimed at four major issues in the oil and gas exploration of the southwestern Huizhou area in Pearl River Mouth Basin, in-depth study on geologic features and oil and gas reservoir forming pattern has been carried out to find out the exploration potential and direction of compound oil and gas reservoirs in this area. There develops the compound formation structure of basement, rifting and depression layers in this area, and a composite hydrocarbon transport system comprised by faults, sandstone layers and the sequence boundaries, which are connected to the several hydrocarbon generation subsags in the adjacent Huixi half graben. Controlled by the subsag-controlling boundary faults, long inherited paleo-uplifts and ancient structural ridges, oil and gas accumulate in multiple series in vertical direction, multiple connected traps horizontally, forming compound reservoirs of various traps. According to the three types of structural zones controlling oil and gas enrichment, the southwestern Huizhou area can be divided into seven compound oil and gas accumulation zones in three categories, which combine into a large compound hydrocarbon accumulation province. Key words: compound oil and gas accumulation play/zone, southwestern Huizhou area, Pearl River Mouth Basin, reservoir forming features, accumulation pattern, exploration potentia

Detrital zircon provenance record of the Oligocene Zhuhai Formation in the Pearl River Mouth Basin, northern South China Sea

The Oligocene Zhuhai Formation has been proven to be one of the main reservoirs in the Pearl River Mouth Basin in the northern South China Sea but its sedimentary provenance remains uncertain and controversial. Here we conducted a systematic study by U-Pb analysis of detrital zircon of the Zhuhai Formation in order to identify the source terrane, investigate the sedimentary source, and establish the framework for the provenance variation during the Oligocene. The study suggests that the detrital zircon in the different structural units reveal marked spatial differences in their age compositions that correlate with the changing sources. The western and eastern parts of the basin have a significantly different provenance manifested by the age compositions of the detrital sediments. The western basin generally has a relatively complex age spectrum and is characterized by a multi-peak distribution, suggesting that the main source was derived from the southern margin of the South China Block. In contrast, the eastern basin displays a dominant population ranging from 131 to 142 Ma, which implies that the sediments were mainly eroded from a nearby source. Our data demonstrate that the Cathaysia Block hinterland and the intrabasinal sources provided dominant provenance contributions to the Pearl River Mouth Basin during the Oligocene. Additionally, Hainan Island and Central Vietnam (eastern Indochina Block) do not appear to have been important sources, whereas Luzon Island and northern Palawan probably provided negligible contributions to the basin during the same time period

Borderline personality disorder and risk of atrial fibrillation: insights from a bidirectional Mendelian randomization study

BackgroundAtrial fibrillation (AF) is one of the most common form of arrhythmia. Previous studies have shown a link between AF and mental illness. However, the causal relationship between mental illness and AF remains unclear. The purpose of this study was to investigate the bidirectional causal relationship between borderline personality disorder (BPD) and AF.MethodWe used the bidirectional Two-sample Mendelian randomization (TSMR) method to evaluate the causal relationship between BPD and AF. Instrumental variables associated with BPD were derived from a genome-wide association study involving 214,816 Europeans (2,637 cases and 212,179 controls). We then obtained atrial fibrillation data from the GWAS meta-analysis (60,620 cases and 970,216 controls). The TSMR analyses were performed in five methods, namely fixed-effect inverse-variance weighted (IVW) method、random-effect IVW method, MR Egger regression method, Weighted median method and Simple mode method. Several sensitivity analyses are used to test the robustness of positive results.ResultsThe fixed-effect inverse-variance weighted model [Odds ratio (OR), 1.033, 95% confidence interval (CI), 1.011-1.056, P = 0.0031], random-effect inverse-variance weighted model (OR, 1.033; 95%CI, 1.005-1.062; P = 0.0191) and Weighted median (OR, 1.034; 95%CI, 1.002-1.068; P = 0.0394) all showed that genetically predicted BPD was associated with an increased risk of AF. Sensitivity analysis using other MR Methods, including the MR-Egger intercept, MR-Presso method, and leave-one-out analyses, showed that the results were robust. In reverse MR analysis, there was no causal relationship of AF on BPD.ConclusionOur study provides a causal relationship between BPD and AF. This means that patients with BPD should be monitored for the occurrence of AF. Early screening and proper management of BPD may show anti-arrhythmic benefits