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Purpose: This study aims to longitudinally investigate developments of the anterior segment in very preterm infants who exhibit normal retinal development outcomes by utilizing a wide-field digital imaging system. Methods: Between June 2021 and June 2022, neonates with a birth weight of <1500 g and/or a gestational age (GA) of less than 32 weeks were included in this study. The participants underwent regular ocular examinations, including sequential evaluations of the anterior segment and the retina, at intervals of 2-5 weeks, starting from birth and continuing until they reached a corrected GA of 48 weeks. Term neonates were selected as normal controls for the study. The study recorded the weight and GA of subjects at the time of examination, as well as indicators of abnormal development in the anterior segment. Results: A total of 48 very preterm infants with normal retinal developmental outcomes were enrolled. The control group included 59 full-term infants. Common anterior segment eye abnormalities such as persistent hyperplasia of primary vitreous, persistent pupillary membranes, iris vessels, and anterior chamber angle vessels gradually subsided with the period in very preterm infants. The vascularity of the iris was substantially higher than in term controls (P < 0.05) at term gestation. The imaging of iris vessels and anterior chamber angle vessels in very preterm infants exhibited a decline at 46 and 47 weeks, respectively, which occurred slightly later compared to term infants. Conclusion: In very preterm infants with normal outcomes, although the developmental process is delayed, they may form a normal anterior segment structure similar to that of full-term infants in the late stages, which is followed up by the wide-field digital imaging system. [ABSTRACT FROM AUTHOR]

Background: It is well-established that serum testosterone in men decreases with age, yet the underlying mechanism of this change remains elusive. Methods: The expression patterns of Fancd2 opposite-strand (Fancd2os) in BALB/c male mice and testicular tissue derived cell lines (GC-1, GC-2, TM3, and TM4) were assessed using real-time polymerase chain reaction (RT-PCR), Western blot and immunofluorescence. The Fancd2os-overexpressing or knockdown TM3 cells were constructed by infecting them with lentivirus particles and were used to evaluated the function of Fancd2os. The testosterone production was measured using enzyme linked immunosorbent assay (ELISA) and the steroidogenic enzymes such as steroidogenic acute regulatory protein (StAR), P450 cholesterol sidechain cleavage (P450scc), and 3β-hydroxysteroid dehydrogenase (3β-HSD) were analysed using RT-PCR. The apoptosis of TM3 cells induced by ultraviolet light or testicular tissues was detected using flow cytometry, Western blot or dUTP-biotin nick end labeling (TUNEL) assays. Pearson correlation analysis was used to assess the correlation between the Fancd2os expression and TUNELpositive staining in mouse testicular Leydig cells. Results: The Fancd2os protein was predominantly expressed in mouse testicular Leydig cells and its expression increased with age. Fancd2os overexpression inhibited testosterone levels in TM3 Leydig cells, whereas knockdown of Fancd2os elevated testosterone production. Fancd2os overexpression downregulated the levels of StAR, P450scc and 3β-HSD, while Fancd2os knockdown reversed this effect. Fancd2os overexpression promoted ultraviolet light-induced apoptosis of TM3 cells. In contrast, Fancd2os knockdown restrained apoptosis in TM3 cells. In vivo assays revealed that higher Fancd2os levels and mouse age were associated with increased apoptosis in Leydig cells and decreased serum testosterone levels. Pearson correlation analysis exhibited a strong positive correlation between the expression of Fancd2os and TUNEL-positive staining in mouse testicular Leydig cells. Conclusion: Our findings suggest that Fancd2os regulates testosterone synthesis via both steroidogenic enzymes and the apoptotic pathway. [ABSTRACT FROM AUTHOR]

Background: Most empirical studies to date have suggested that alpine plants in the central Qinghai-Tibetan Plateau (QTP) originated from the south-eastern QTP. However, previous phylogeographcial analysis of Potentilla fruticosa suggested that it diversified in the central QTP, which has also been assumed to have been a glacial refugium, and expanded to the north-eastern regions during the mid-Holocene period. Aim: We reappraise this claim in the light of information acquired from sampling, haplotyping and analysing additional populations. Methods: We sequenced the chloroplast trnT-L intergenic spacer of 346 individuals collected from 52 populations. We reconstructed phylogenetic relationships among haplotypes through Bayesian and Network analysis, and used several methods for demographic analysis. Results: Some common and highly divergent haplotypes were distributed in the central, western and south-eastern QTP. Mismatch and other population genetic analyses applied to our data suggested that a distinct range expansion had occurred between approximately 30,000 and 325,000 years ago (kya). Conclusions: Besides the possible postglacial expansion in the north-eastern QTP, our results further suggested that the range of the species radically expanded across the whole Plateau before the last glacial maximum (around 18 kya) and the south-eastern, western and central QTP regions had together provided important refugia during recent glacial stages. These findings, in contrast to the previous conclusions, highlight the importance of adequate sampling strategies in phylogeographical studies. [ABSTRACT FROM AUTHOR]

Sepsis is a life-threatening condition that can lead to several organ failures including kidney. In this study, we investigated the roles of GAS5 and miR-579-3p in regulating cell pyroptosis in the sepsis-induced renal injury model. Lipopolysaccharide (LPS) treatment or cecal ligation and puncture (CLP) surgery was used to create the in vitro and in vivo sepsis-induced renal injury model. The interactions between GAS5 and miR-579-3p, and miR-579-3p and SIRT1 were determined by bioinformatic prediction, luciferase reporter assay, and RIP assay. In vitro cell pyroptosis was examined by flow cytometry marked with active caspase-1 and PI. The protein levels of IL-1b and IL-18 induced by cell pyroptosis were quantified using ELISA assay. In vivo renal injuries were evaluated with HE and TUNEL stainings, bacterial load in serum and creatinine, and blood urea nitrogen content analyses. Expression levels of GAS5, miR-579-3p, pyroptosis, and SIRT1/PGC-1a/Nrf2 pathway-related molecules were evaluated by qRTPCR or Western blot. GAS5 and SIRT1 were downregulated, whereas miR-579-3p was upregulated in in vitro and in vivo sepsisinduced renal injury models. GAS5 negatively and directly regulated miR-579-3p to reduce cell pyroptosis via the activation of SIRT1/PGC-1a/Nrf2 pathway. In addition, miR-579-3p suppressed PGC-1a/Nrf2 pathway to induce cell pyroptosis by directly targeting SIRT1. What's more, overexpression of GAS5, or knockdown of miR-579-3p, enhanced SIRT1 expression that led to the improved survival rate, reduced the weight loss, and relieved renal injuries in septic mice. Overexpression of GAS5 demonstrated protective effects against sepsis-induced renal injury via downregulating miR-579-3p and activating SIRT1/PGC-1a/Nrf2 pathway to inhibit cell pyroptosis. [ABSTRACT FROM AUTHOR]

Soil bacteria adapt to diverse and rapidly changing environmental conditions by sensing and responding to environmental cues using a variety of sensory systems. Two- component systems are a widespread type of signal transduction system present in all three domains of life and typically are comprised of a sensor kinase and a response regulator. Many two-component systems function by regulating gene expression in response to environmental stimuli. The bacterial chemotaxis system is a modified two- component system with additional protein components and a response that, rather than regulating gene expression, involves behavioral adaptation and results in net movement toward or away from a chemical stimulus. Soil bacteria generally have twenty to forty or more chemoreceptors encoded in their genomes. To simplify the identification of chemoeffectors (ligands) sensed by bacterial chemoreceptors, we constructed hybrid sensor proteins by fusing the sensor domains of Pseudomonas putida chemoreceptors to the signaling domains of the Escherichia coli NarX/NarQ nitrate sensors. Responses to potential attractants were monitored by β-galactosidase assays using an E. coli reporter strain in which the nitrate-responsive narG promoter was fused to lacZ. Hybrid receptors constructed from PcaY, McfR, and NahY, which are chemoreceptors for aromatic acids, TCA cycle intermediates, and naphthalene, respectively, were sensitive and specific for detecting known attractants, and the β-galactosidase activities measured in E. coli correlated well with results of chemotaxis assays in the native P. putida strain. In addition, a screen of the hybrid receptors successfully identified new ligands for chemoreceptor proteins and resulted in the identification of six receptors that detect propionate. [ABSTRACT FROM AUTHOR]

Transmission electron microscopy (TEM) is a unique and powerful tool for observation of nanoparticles. However, due to the uneven spatial distribution of particles conventionally dried on copper grids, TEM is rarely employed to evaluate the spatial distribution of nanoparticles in aqueous solutions. Here, we present a microchip nanopipet with a narrow chamber width for sorting nanoparticles from blood and preventing the aggregation of the particles during the drying process, enabling quantitative analysis of their aggregation/agglomeration states and the particle concentration in aqueous solutions. This microchip is adaptable to all commercial TEM holders. Such a nanopipet proves to be a simple and convenient sampling device for TEM image-based quantitative characterization. [ABSTRACT FROM AUTHOR]