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Objective. To assess the effectiveness of atrioventricular valve regurgitation (AVVR) detection using color Doppler in the four-chamber view (4CV) for identifying atrioventricular septal defects (AVSDs) during 11–13 + 6 weeks’ gestation. This study compares AVVR detection to conventional 2D ultrasound and investigates associations between AVSD and increased nuchal translucency thickness (NT), as well as additional cardiac, extracardiac, and chromosomal abnormalities in the first trimester. Materials and Methods. This prospective study analyzed data from singleton pregnancies diagnosed with AVSD at 11–13 weeks gestation. It included routine ultrasound examinations focusing on fetal anatomy, NT measurement, and blood flow analysis across AVVR using both color and directional power Doppler. Evaluations targeted the 4CV and the three-vessel and trachea views (3VT). Ratios such as LAVV/RAVV and main pulmonary artery-to-aorta (PA/AO) diameter were also calculated. Results. Over three years, 452 fetuses were diagnosed with congenital heart disease in the first trimester, including 25 cases of AVSD (21 complete, 1 partial, and 3 intermediate). Seventeen cases were isolated AVSDs, 13 associated with heterotaxia syndrome, one with tetralogy of Fallot, and two survived. Among these, 92% showed AVVR, 61.54% had NT above the 95th percentile, and 32.0% lacked a nasal bone. AVVR was a more reliable indicator of AVSD than other ultrasonic markers. Conclusion. AVSD exhibits a diverse range of clinical presentations. A comprehensive review of both intracardiac and extracardiac anomalies is essential. AVVR detected during NT scanning in the first trimester can confirm the presence of AVSD.

Two species of Blackwellomyces (Clavicipitaceae, Hypocreales, Ascomycota) were discovered during an investigation of the diversity of entomopathogenic fungi. A new fungus and one known fungal species that were gathered from Yunnan Province were described in this study. Blackwellomyces changningensis, sp. nov. was described using morphology and phylogenetic evidence from 14 mitochondrial protein-coding gene (PCG) data sets (atp6, atp8, atp9, cob, cox1, cox2, cox3, nad1, nad2, nad3, nad4, nad5, nad6, and nad4L) and six nuclear genes (ITS [ITS4 and ITS5], 18S nuc rDNA [18S], 28S nuc rDNA [28S], tef1-α, rpb1, and rpb2). B. changningensis were found parasitic to Lepidoptera larvae and to produce filiform ascospores with septations. The asexual conidia were ovoid to ellipsoid in shape. Phylogenetic analysis and morphological observations concurred that the fungus belonged to a different species within the genus of Blackwellomyces. The foundation for further taxonomic, genetic, and evolutionary biological studies of the genus Blackwellomyces was laid by this work. [ABSTRACT FROM AUTHOR]

SLC7A11 plays a pivotal role in tumour development by facilitating cystine import to enhance glutathione synthesis and counteract oxidative stress. Disulphidptosis, an emerging form of cell death observed in cells with high expression of SLC7A11 under glucose deprivation, is regulated through reduction–oxidation reactions and disulphide bond formation. This process leads to contraction and collapse of the F‐actin cytoskeleton from the plasma membrane, ultimately resulting in cellular demise. Compared to other forms of cell death, disulphidptosis exhibits distinctive characteristics and regulatory mechanisms. This mechanism provides novel insights and innovative strategies for cancer treatment while also inspiring potential therapeutic approaches for other diseases. Our review focuses on elucidating the molecular mechanism underlying disulphidptosis and its connection with the actin cytoskeleton, identifying alternative metabolic forms of cell death, as well as offering insights into disulphidptosis‐based cancer therapy. A comprehensive understanding of disulphidptosis will contribute to our knowledge about fundamental cellular homeostasis and facilitate the development of groundbreaking therapies for disease treatment. [ABSTRACT FROM AUTHOR]

The significance of the roughness of particles in flotation has been recognized for several decades. In this study, to investigate the effect of particle roughness, a series of rod milling with different grinding durations is performed on the quartz particles. Subsequently, the particle roundness, wetting rate, and floatability are measured. Finally, the flotation kinetic experiments are conducted based on a fixed particle size, and the interaction energy between rough particles and bubbles is calculated based on extended DLVO (E-DLVO) theory. Results show that by increasing the grinding time, the hydrophobic particle surface roughness increases, and the improved flotation rate constant increases. While the results of the E-DLVO calculation show that the interaction energy barrier between particles and bubbles decreases significantly as the roughness increases, the theoretical calculation and the experimental results confirm that an increase in the particle surface roughness decreases the interaction energy barrier between particle bubbles and increases the flotation rate. [ABSTRACT FROM AUTHOR]

A notable feature of volcanic activity in the Halmahera arc since the Middle Miocene is that eruptions have occurred episodically from south to north, rather than simultaneously. However, the dynamic cause of the volcanic age disparity between the northern and southern regions remains unresolved. To investigate this, thermal simulation methods were employed to calculate the temperature structures of the subducted slab and mantle wedge under varying movement rates of subduction and overriding plates. Simulation results indicate that arc magmatism is favored at lower subduction rates or higher overriding plate movement rates. During the Middle Miocene, the northward drift of the Australian plate propelled the Obi microplate southward via left-lateral strike-slip faults, accelerating its movement rate. In contrast, the movement rate of the Halmahera microplate in the north remained lower, unaffected by the Australian plate. The accelerated movement of the Obi microplate resulted in the rapid generation of a higher temperature zone, facilitating arc volcanism on Obi Island in the late Middle Miocene. Meanwhile, the lower movement rate of the Halmahera microplate delayed the formation of a favorable high-temperature zone for arc volcanism, leading to the emergence of volcanism on Halmahera Island in the late Pliocene. [ABSTRACT FROM AUTHOR]

Surfactants are amphiphilic molecules that are capable of mixing water and oil. Biosurfactants are eco-friendly, low-toxicity, and stable to a variety of environmental factors. Optimizing conditions for microorganisms to produce biosurfactants can lead to improved production suitable for scaling up. In this study, we compared heterologous expression levels of the luminescence system luxCDABE operon controlled by regulatable promoters araC-PBAD and its strong version araC-PBAD-SD in Escherichia coli K12, Pseudomonas aeruginosa PAO1, and P. putida KT2440. Real-time monitoring of luminescence levels in the three strains indicated that luxCDABE controlled by araC-PBAD-SD promoter with 0.2% arabinose supplementation in P. putida produced the highest level of luminescence. By using the araC-PBAD-SD promoter-controlled rhlAB expression in P. putida, we were able to produce mono-rhamnolipid at a level of 1.5 g L−1 when 0.02% arabinose was supplemented. With the same system to express olsB, lyso-ornithine lipid was produced at a level of 10 mg L−1 when 0.2% arabinose was supplemented. To our knowledge, this is the first report about optimizing conditions for lyso-ornithine lipid production at a level up to 10 mg L−1. Taken together, our results demonstrate that regulatable araC-PBAD-SD promoter in P. putida KT2440 is a useful system for heterologous production of biosurfactants. [ABSTRACT FROM AUTHOR]

Many enzymes in the Raetz pathway for lipid A biosynthesis in Escherichia coli are essential. A homologous protein Pa1792|LpxH in Pseudomonas aeruginosa is known to complement the loss of LpxH in E. coli. Genome-wide transposon-insertion sequencing analysis indicates that lpxH is essential in P. aeruginosa. However, genetic analysis of lpxH in P. aeruginosa has not been carried out, partly because the conditional alleles of essential genes are not readily constructed. In this study, we first constructed a plasmid-based temperature-sensitive mutant ΔlpxH/pTS-lpxH or lpxH(Ts) in P. aeruginosa PAO1. Spot-plating assay indicated that lpxH(Ts) was lethal at a restrictive temperature, confirming its essentiality for growth. Microscopic analysis revealed that lpxH(Ts) exhibited an oval-shaped morphology, suggesting that lpxH was required for rod-shape formation. SDS-PAGE and Western blotting analysis showed that lpxH(Ts) failed to synthesize lipid A, consistent with its function in lipid A biosynthesis. Strong expression of lpxH but not the non-homologous isoenzyme lpxI or lpxG impeded growth and caused cell lysis, implying that lpxH-specific cofactors were required for this toxic effect in P. aeruginosa. Together, our results demonstrate that lpxH is essential for lipid A biosynthesis, rod-shaped growth, and viability in P. aeruginosa. We propose that this plasmid-based conditional allele is a useful tool for the genetic study of essential genes in P. aeruginosa. [ABSTRACT FROM AUTHOR]

Pa0665 in Pseudomonas aeruginosa shares homologous sequences with that of the essential A-type iron–sulfur (Fe-S) cluster insertion protein ErpA in Escherichia coli. However, its essentiality in P. aeruginosa and its complementation with E. coli erpA has not been experimentally examined. To fulfill this task, we constructed plasmid-based ts-mutant Δpa0665/pTS-pa0665 using a three-step protocol. The mutant displayed growth defects at 42 °C, which were complemented by expressing ec.erpA. Microscopic observations indicated a petite cell phenotype for Δpa0665/pTS-pa0665 at 42 °C, correlated with the downregulation of the oprG gene. RNA sequencing revealed significant transcriptional changes in genes associated with the oxidative phosphorylation (OXPHOS) system, aligning with reduced ATP levels in Δpa0665/pTS-pa0665 under 42 °C. Additionally, the ts-mutant showed heightened sensitivity to H2O2 at 42 °C. Overall, our study demonstrates the essential role of pa0665 for OXPHOS function and is complemented by ec.erpA. We propose that the plasmid-based ts-allele is useful for genetic analysis of essential genes of interest in P. aeruginosa. [ABSTRACT FROM AUTHOR]

Intervertebral disc degeneration (IDD) is a prevalent musculoskeletal degenerative disorder worldwide, and ~40% of chronic low back pain cases are associated with IDD. Although the pathogenesis of IDD remains unclear, the reduction in nucleus pulposus cells (NPCs) and degradation of the extracellular matrix (ECM) are critical factors contributing to IDD. Notochordal cells (NCs), derived from the notochord, which rapidly degrades after birth and is eventually replaced by NPCs, play a crucial role in maintaining ECM homeostasis and preventing NPCs apoptosis. Current treatments for IDD only provide symptomatic relief, while lacking the ability to inhibit or reverse its progression. However, NCs and their secretions possess anti‐inflammatory properties and promote NPCs proliferation, leading to ECM formation. Therefore, in recent years, NCs therapy targeting the underlying cause of IDD has emerged as a novel treatment strategy. This article provides a comprehensive review of the latest research progress on NCs for IDD, covering their biological characteristics, specific markers, possible mechanisms involved in IDD and therapeutic effects. It also highlights significant future directions in this field to facilitate further exploration of the pathogenesis of IDD and the development of new therapies based on NCs strategies. [ABSTRACT FROM AUTHOR]