PLoS ONE最新文献

G-protein coupled receptors inhibit Cav2.2 N-type Ca2+ channels by a fast, voltage-dependent pathway mediated by Gαi/Gβγ and a slow, voltage-independent pathway mediated by Gαq-dependent reductions in phosphatidylinositol 4,5-bisphosphate (PIP2) or increases in arachidonic acid. Studies of these forms of regulation generally employ Ba2+ as the permeant ion, despite that Ca2+ -dependent pathways may impinge upon G-protein modulation. To address this possibility, we compared tonic G-protein inhibition of currents carried by Ba2+ (IBa) and Ca2+ (ICa) in HEK293T cells transfected with Cav2.2. Both IBa and ICa exhibited voltage-dependent facilitation (VDF), consistent with Gβγ unbinding from the channel. Compared to that for IBa, VDF of ICa was less sensitive to an inhibitor of Gα proteins (GDP-β-S) and an inhibitor of Gβγ (C-terminal construct of G-protein coupled receptor kinase 2). While insensitive to high intracellular Ca2+ buffering, VDF of ICa that remained in GDP-β-S was blunted by reductions in PIP2. We propose that when G-proteins are inhibited, Ca2+ influx through Cav2.2 promotes a form of VDF that involves PIP2. Our results highlight the complexity whereby Cav2.2 channels integrate G-protein signaling pathways, which may enrich the information encoding potential of chemical synapses in the nervous system.

Introduction: Low birth weight continues to pose significant challenges to healthcare systems worldwide. Despite substantial improvement in various public health indicators, many developing countries have failed to achieve a significant reduction in low birth weight rates. One major obstacle is the sparsity of data on the determinants of low birth weight. Here, we aim to determine the composition and risk factors for low birth weight in Sri Lanka, a prototype developing nation.

Methodology: We conducted a countrywide multicentre cross-sectional study in August and September 2023 in 13 purposively selected hospitals representing all nine provinces and different tiers of specialist hospitals in Sri Lanka. All live-born neonates were recruited prospectively, and their mothers were interviewed by trained data collectors to gather information on socio-demographic background, medical and obstetric history, and delivery details. Birth weight was measured immediately after the birth by trained healthcare personnel attending the delivery.

Results: A total of 9130 live-born neonates were recruited, of which 52% were males. The mean birth weight was 2827g (95%CI 2817-2838g), and 1865 (20.4%) newborns were low birth weight. The prevalence of prematurity was 10.9% (n = 998), and 1819 (20.0%) neonates were born small for gestational age. Of the low birth weight neonates, 64% were small for gestational age, and 37% were preterm; 11% were both small for gestational age and preterm. Teenage pregnancy (p = 0.022), low maternal pre-pregnancy body mass index (p<0.001), inadequate weight gain during pregnancy (p<0.001), maternal anaemia at delivery (p = 0.020), chronic lung disease (p = 0.019), and pregnancy induced hypertension (p = 0.019) were significant modifiable risk factors for small for gestational age.

Conclusion: This study presents the results of one of the most extensive country-wide studies evaluating the composition and determinants of low birth weight. The study highlights the importance of considering small for gestational age and prematurity as separate categories of low birth weight. Small for gestational age contributes to approximately two-thirds of the low birth weight burden. Therefore, targeting modifiable risk factors for small for gestational age while mitigating the burden of prematurity is the most feasible approach to reduce the prevalence of low birth weight in developing countries, including Sri Lanka.

Previous studies have examined the cellulase activity of Crassostrea gigas (Pacific oyster) and suggested its potential utilization of terrestrial lignocellulose. However, no studies have been conducted to comprehensively assess its endogenous cellulases. Therefore, our objective was to identify the cellulases present in C. gigas through transcriptome and genomic analyses. The results showed that there are 10 cellulase orthologs, seven of which are endogenous. Phylogenetic analysis revealed that two of these cellulases belong to the glycoside hydrolase family (GHF) 5, four to GHF9, and one to GHF45. An alignment of the amino acid sequences suggested the presence of at least endo-β-1,4-glucanase. Therefore, C. gigas is likely capable of decomposing lignocellulose into glucose. This finding supports the fact that C. gigas, a globally commercial bivalve species, thrives in environments that lack phytoplankton, such as mangroves.

[This corrects the article DOI: 10.1371/journal.pone.0262519.].

Soil erosion is a pervasive global challenge and a significant ecological and environmental concern in China. Its occurrence frequently triggers ecological crises, including soil degradation and water contamination. It is of great scientific and practical significance to study the factors influencing the mechanism of soil erosion occurrence. Economic development in the Dabie Mountains of China has necessitated the conversion of vast tracts of forest land into economic crops, notably tea gardens and orchards, thereby disrupting soil structure and precipitating large-scale soil erosion. Rainfall serves as the primary catalyst for soil erosion in this region. Therefore, this study was designed to reveal the evolution characteristics of rainfall-induced slope erosion and the key influencing factors in the forest land converted to cash crop area in Dabie Mountains. It focused on a tea plantation slope of the Dabie Mountains, employing four rainfall scenarios, i.e. light rain, moderate rain, heavy rain, and heavy rain following drought, to conduct in-situ simulation experiments, mirroring the prevalent rainfall patterns in the study region. Monitoring stations for soil moisture content, slope runoff, and soil erosion were strategically positioned at varying depths across experimental plots with vegetation cover percentages of 20%, 40%, and 60%. Mathematical methods of descriptive statistics were used to analyze the monitored runoff, soil erosion and soil water content data, and to study the characteristics of their changes and response relationships. The findings underscore that rainfall prompts a swift surge in surface soil moisture, destabilizing the soil surface and culminating in slope erosion; thus, the rate of change in surface soil moisture content emerges as a pivotal indicator for predicting slope soil erosion. Furthermore, within the bounds of rainfall infiltration, preceding drought conditions followed by intense rainfall exacerbate soil erosion accumulation, highlighting the significance of initial soil moisture content as a critical factor. Lastly, for the economic crop cultivation zones in the Dabie Mountains, achieving a vegetation cover of 40% or more can significantly enhance soil water retention capacity and the overall soil and water conservation efficacy.

Injuries sustained during military conflict can significantly impact appearance. Yet, little is known about the psychosocial experiences of veterans with conflict-related appearance-altering injuries (AAI) and whether current civilian interventions are appropriate for this group. To inform the development of acceptable and effective support for veterans with appearance-related psychosocial difficulties, this study aimed to identify factors associated with psychosocial adjustment to an altered appearance among both veterans and civilians with AAI. A cross-sectional online survey was completed by 121 veterans and 197 civilians who had sustained AAI. Multivariable regression was used to examine factors related to adjustment in the two groups. Overall, both groups reported similar experiences, with some key exceptions. Veterans reported significantly greater depression and Post Traumatic Stress Disorder, significantly lower Body Image (BI) psychological flexibility, BI life engagement, and higher perceived appearance-related stigma. BI psychological flexibility was identified as a key predictor of appearance-related outcomes in both groups. Self-compassion predicted social anxiety and depression symptoms in both groups, but only appearance outcomes among civilians. Based on these identified associated factors, it is suggested that both groups, but particularly veterans, may benefit from an Acceptance and Commitment Therapy-based intervention, including explicit self-compassion activities, and practical social skills training.

The stack is the core component of large-scale flow battery system. Based on the leakage circuit, mass and energy conservation, electrochemicals reaction in porous electrode, and also the effect of electric field on vanadium ion cross permeation in membrane, a model of kilowatt vanadium flow battery stack was established. The electro chemical reaction parameters, ion concentration and temperature of each single cell in the stack were calculated respectively. The imbalance of vanadium ion concentration and the effects of current density and electrolyte temperature on the electrolyte imbalance in the stack were studied.

Background: Retinal problems are critical because they can cause severe vision loss if not treated. Traditional methods for diagnosing retinal disorders often rely heavily on manual interpretation of optical coherence tomography (OCT) images, which can be time-consuming and dependent on the expertise of ophthalmologists. This leads to challenges in early diagnosis, especially as retinal diseases like diabetic macular edema (DME), Drusen, and Choroidal neovascularization (CNV) become more prevalent. OCT helps ophthalmologists diagnose patients more accurately by allowing for early detection. This paper offers a hybrid SE (Squeeze-and-Excitation)-Enhanced Hybrid Model for detecting retinal disorders from OCT images, including DME, Drusen, and CNV, using artificial intelligence and deep learning.

Methods: The model integrates SE blocks with EfficientNetB0 and Xception architectures, which provide high success in image classification tasks. EfficientNetB0 achieves high accuracy with fewer parameters through model scaling strategies, while Xception offers powerful feature extraction using deep separable convolutions. The combination of these architectures enhances both the efficiency and classification performance of the model, enabling more accurate detection of retinal disorders from OCT images. Additionally, SE blocks increase the representational ability of the network by adaptively recalibrating per-channel feature responses.

Results: The combined features from EfficientNetB0 and Xception are processed via fully connected layers and categorized using the Softmax algorithm. The methodology was tested on UCSD and Duke's OCT datasets and produced excellent results. The proposed SE-Improved Hybrid Model outperformed the current best-known approaches, with accuracy rates of 99.58% on the UCSD dataset and 99.18% on the Duke dataset.

Conclusion: These findings emphasize the model's ability to effectively diagnose retinal disorders using OCT images and indicate substantial promise for the development of computer-aided diagnostic tools in the field of ophthalmology.

High-frequency electrical stimulation (HFS) of the skin using a multi-pin electrode activating epidermal nociceptors is used to explore spinal central sensitization in humans. Most previous studies applied HFS to the volar forearm. To prepare for clinical applications in which HFS could be applied to different body sites, this study compared the secondary hyperalgesia induced by stimulation of the foot dorsum vs. the forearm in 32 healthy volunteers. HFS consisted in five 1-s trains of 100 Hz pulses (inter-train interval: 10 s; intensity: 20x detection threshold) delivered via a novel electrode optimized for stimulation of different body sites (ten 0.25 mm pins in a 5-mm circle). Pinprick sensitivity was assessed before HFS and 30-240 minutes after HFS, at the treated site and the corresponding contralateral site. The area of hyperalgesia was quantified. HFS to the foot induced a significant increase in pinprick sensitivity of the surrounding skin, similar in magnitude to the increase at the forearm, and decaying similarly over time (half-lives 150 vs. 221 min). The radius of secondary hyperalgesia was smaller at the foot (22 mm) compared to the forearm (38 mm, p < 0.001), and decreased more rapidly over time (53 vs. 87 min, p < 0.01). Our results show that strength of HFS-induced secondary hyperalgesia can be used as indicator of spinal central sensitization across body sites, and thereby profile patients with localized or regional pain conditions. The size of the area of hyperalgesia may depend on innervation density and peripheral receptive field sizes.

In this study, we tested the overall hypothesis that CC expansion and early embryo development would be improved by including follicular fluid (FF) from small or large follicles in the oocyte maturation medium. In the first experiment, FF aspirated from bovine abattoir ovaries was added to the maturation medium at 0, 25, 50, 75 or 100%. Images of individual COCs were captured at 0, 6, 12 and 19 hours (h) of the maturation period and analyzed to calculate change in the total area over time. Cumulus cell expansion was greatest in COCs matured in 75% and 50% FF, and these differences were detectable at 12 (75% FF only) and 19 h (50% and 75% FF) of maturation. The improvement in CC expansion was greatest when FF from small follicles was used. Treatments for the subsequent experiments were selected based upon the results of the first experiment. Oocyte nuclear maturation rates were observed after supplementing the maturation medium with 0 or 75% FF and maturing for 19 h. The rate of nuclear maturation as determined by the presence or absence of the first polar body was similar between control (0% FF) and treated (75% FF) groups. In the final experiment, COCs were matured in 0%, 50% or 75% FF in preparation for IVF. Duration of the maturation period (12, 19 or 22 h) and size of the follicles from which FF was collected (small or large) also varied. In general, FF supplementation at 50% did not affect the zygotes' developmental potential (neither increased nor decreased). Supplementation of maturation medium with 75% FF from small follicles consistently reduced measures of embryo development while 75% FF from large follicles yielded mixed results. It is concluded that FF supplementation improves CC expansion, but the greater CC expansion does not benefit subsequent embryo development. Notably, however, the 50% FF treatment did not reduce blastocyst rates, indicating that FF can be included in maturation media at concentrations of 50% or less with no detriment to IVF outcomes.