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Microscopic animals are often thought to be widely distributed due to their small size and specific adaptations. However, evidences show that bdelloid rotifers in bryophytes exhibit habitat specialization, with species composition varying by microhabitat. This indicates that their distribution is influenced by complex ecological processes, warranting further research, particularly at the microscale. In this study, we tested whether species richness and composition of bdelloid rotifers differ across bryophyte species, forms, characteristics, and seasons to understand their ecological distribution and habitat preferences in limnoterrestrial environments. Bdelloid rotifers were identified and counted from bryophyte samples collected in April (low rainfall), August (moderate rainfall), and December 2022 (high rainfall) at Bang Burd Beach Forest, Chumphon Province, Thailand. The results revealed high bdelloid diversity, with 22 species identified, 14 of which are new records for Thailand, raising the known number to 30. However, species richness did not vary across bryophyte variables or seasons, with substantial overlap in species composition across these variables. Additionally, there was no strong habitat preference between bdelloid rotifers and bryophyte species. These results confirm a low degree of habitat specialization of bdelloid rotifers in tropical limnoterrestrial environments.

Background: The morphology and hunting behavior of thresher sharks make them easily distinguishable. These species are distributed across the Tropical Pacific Ocean feeding on squid and small fish. However, ontogenetic changes in their feeding strategies and habitat use are still unknown in this region.

Methods: We examined the δ¹³C and δ¹⁵N signatures in vertebral collagen from populations of Alopias pelagicus and Alopias superciliosus inhabiting the Galapagos Marine Reserve, focusing on three maturity stages: neonate, juvenile and adult. The vertebrae samples were taken from the seizure of illegal fishing activities carried out by a foreign fleet within the Galapagos archipelago. A total of thirty-three vertebrae from A. pelagicus and twenty-one from A. superciliosus were analyzed.

Results: Both species displayed significant differences in their δ¹⁵N values (p < 0.001), but not in δ¹³C (p = 0.230), suggesting a similar habitat use, but different prey consumption. Throughout their ontogeny, A. pelagicus displayed isotopic differences (p < 0.001), where neonates showed lower δ¹³C values and higher δ¹⁵N values compared to juveniles, probably because they still reflect the isotopic signatures of their mothers even after the first year of life. This study highlights trophic differences between both species, accompanied by an ontogenetic variation in A. pelagicus, aspects that allow us to understand the role of these species within the dynamics of the Eastern Tropical Pacific ecosystem.

GABA (γ-aminobutyric acid) is a non-protein amino acid that occurs naturally in the human brain, animals, plants and microorganisms. It is primarily produced by the irreversible action of glutamic acid decarboxylase (GAD) on the α-decarboxylation of L-glutamic acid. As a major neurotransmitter in the brain, GABA plays a crucial role in behavior, cognition, and the body's stress response. GABA is mainly synthesized through the GABA shunt and the polyamine degradation pathways. It works through three receptors (GABA_A, GABA_B, and GABA_C), each exhibiting different pharmacological and physiological characteristics. GABA has a variety of physiological roles and applications. In plants, it regulates growth, development and stress responses. In mammals, it influences physiological functions such as nervous system regulation, blood pressure equilibrium, liver and kidneys enhancement, hormone secretion regulation, immunity enhancement, cancer prevention, as well as anti-aging effects. As a biologically active ingredient, GABA possesses unique physiological effects and medicinal value, leading to its widespread application and substantially increased market demand in the food and pharmaceutical industries. GABA is primarily produced through chemical synthesis, plant enrichment and microbial fermentation. In this review, we first make an overview of GABA, focusing on its synthesis, metabolism, GABA receptors and physiological functions. Next, we describe the industrial production methods of GABA. Finally, we discuss the development of ligands for the GABA receptor binding site, the prospects of GABA production and application, as well as its clinical trials in potential drugs or compounds targeting GABA for the treatment of epilepsy. The purpose of this review is to attract researchers from various fields to focus on GABA research, promote multidisciplinary communications and collaborations, break down disciplinary barriers, stimulate innovative research ideas and methods, and advance the development and application of GABA in medicine, agriculture, food and other fields.

Background: The impact of acute mountain sickness (AMS) on individuals ascending to plateaus, soon after exposure to high altitudes, is well-documented. However, the specific relationship between AMS and alterations in blood parameters remains unclear.

Methods: A total of 40 healthy volunteers were recruited. Following their arrival at an altitude of 3,300 m, an AMS questionnaire survey was administered 48 h later. Based on the AMS scores obtained, participants were categorized into three groups: non-AMS, mild AMS, and moderate/severe AMS (encompassing both moderate and severe cases). Blood routine tests were performed on all groups at 3-, 7-, and 30-days post-arrival at the plateau, with blood oxygen saturation tests conducted at 3 and 30 days after rapidly entering the plateau.

Results: In the current investigation, a total of 40 participants were stratified into non-AMS (n = 24), mild-AMS (n = 8), and moderate/severe-AMS (n = 8) cohorts subsequent to rapid ascension to an altitude of 3,300 m. The incidence of AMS in this study was 40%. Noteworthy elevations in red blood cells (RBC), hemoglobin (Hb), and hematocrit (HCT) levels were noted at the 3-day mark post-ascent across all delineated groups. By the 7th day, the moderate/severe-AMS cohort displayed sustained increments in Hb and HCT levels, whereas solely HCT levels rose in the mild-AMS and non-AMS cohorts. Upon reaching the 30-day milestone, the moderate/severe-AMS group demonstrated a reduction in RBC, Hb, and HCT levels, while only HCT levels decreased in the mild-AMS and non-AMS groups. Furthermore, it was observed that all groups exhibited notable reductions in oxygen saturation (SpO₂) at 3 days post-ascent, followed by a partial recovery at 30 days, albeit remaining below baseline levels. The correlation analysis results indicated that RBC, Hb, and HCT exhibited a positive correlation with the severity of AMS after a 7-day acclimatization period at high altitude. Conversely, SpO₂ demonstrated a negative correlation with the severity of AMS following the same duration at high altitude. The findings of the study suggest a strong association between alterations in RBC, Hb, and HCT levels and AMS, particularly among individuals in the moderate/severe-AMS category who displayed more significant fluctuations in these parameters.

Conclusion: Individuals suffering from moderate to severe AMS demonstrated increased levels of RBC, Hb, and HCT, as well as reduced SpO₂, indicating a greater need for oxygen adaptation to high-altitude hypoxia. These findings emphasize the physiological adjustments to high altitudes and their potential implications for the treatment of AMS.

The lack of reliable data on length-mass relationships, essential to obtain accurate biomass estimates, limits our ability to easily assess secondary production by aquatic invertebrates. In the absence of published equations from similar habitat conditions, authors often borrow equations developed in geographic regions with different climate conditions, which may bias biomass estimates. A literature overview of published size-mass relationships for Portugal and Sweden highlights the need for further data within these biogeographic regions. We increased the number of equations available to Southern and Northern Europe, developing 18 new length-mass relationships for two families and 10 genera in Portugal and Sweden. All equations were published for the first time for these countries, except the genus Asellus. Our length-mass relationships were obtained from specimens collected on a one-time sampling of eight ponds in Portugal and five ponds in Sweden during late spring in 2023. Dry mass (DM) was modelled as a function of body length (BL), using the natural log-linear function with a power model (ln DM = ln a + b × ln BL). The equations obtained were compared with linear mixed models testing the fixed effects of "body length" and "country", as well as their interaction. A comparison of the equations developed in this study showed country-specific differences for all taxa, expect the genus Caenis, indicating a low potential transferability of the equations between Southern and Northern Europe. In contrast, the comparison of the equation obtained for A. aquaticus in this study with an equation published for this taxon in Sweden showed great similarities, suggesting a high transferability. Recommending caution in the borrowing of published length-mass equations, that can differ drastically between different geographic and climatic regions, especially at larger sizes, we provide a series of guidelines and good practices in this field.

Background: Although maintaining a stable body temperature during the perioperative period is crucial for the recovery of neonates, hypothermia frequently occurs during surgical procedures in this vulnerable population. A comprehensive analysis of intraoperative details, including medical history and monitoring, is therefore essential for understanding temperature variations and identifying risk factors for severe hypothermia.

Objective: In this study, we delineated the characteristic patterns of intraoperative temperature fluctuations in neonates and determined the risk factors impacting the severity of hypothermia.

Methods: We conducted a retrospective, single-center study, enrolling 648 subjects who underwent surgery under general anesthesia and collected demographic, perioperative, and intraoperative data.

Results: Intraoperative hypothermia occurred in 79.17% of the neonates. Significant risk factors for severe hypothermia included surgery type (OR, 1.183; 95%, CI [1.028-1.358]; p = 0.018), preoperative weight (OR, 0.556; 95% CI [0.412-0.748]; p < 0.01), infusion and transfusion volume (mL/kg) (OR, 1.011; 95% CI [1.001-1.022]; p = 0.018), and duration of hypothermia (OR, 1.011; 95% CI [1.007-1.014]; p < 0.01). Preterm neonates experienced a greater temperature drop than did full-term neonates. The nadir of intraoperative temperature occurred approximately 90 min after surgery, followed by a brief stabilization period and a slow recovery process.

Conclusion: The significant incidence of intraoperative hypothermia in neonates highlights the need for efficient strategies that reduce both the frequency and severity of this condition.

Objective: To investigate the current status of knowledge, attitude, and practice (KAP) of healthcare professionals in stroke-related departments of primary-level tertiary hospitals regarding the prevention and treatment of hemiplegic shoulder pain, and to analyze influencing factors. This aims to provide a reference for further training, guidance, and management of hemiplegic shoulder pain.

Methods: A total of 123 healthcare professionals from stroke-related departments of two tertiary hospitals in a county-level city in Zhejiang province were selected as the research subjects from March 6, 2023, to March 14, 2023. Written informed consent was obtained from all study participants prior to their inclusion in the study. A questionnaire survey was conducted to assess their KAP status on the prevention and treatment of hemiplegic shoulder pain, and statistical analysis was performed using SPSS 23.

Results: The scores for knowledge (29.97 ± 9.94), attitude (27.7 ± 2.81), and behavior (29.86 ± 7.86) among the 123 healthcare professionals indicated that department and position were influencing factors for KAP (P < 0.05).

Conclusion: The overall KAP of healthcare professionals in stroke-related departments of primary hospitals regarding the prevention and treatment of hemiplegic shoulder pain needs improvement. Strengthening relevant knowledge and skills training is necessary to reduce the incidence of hemiplegic shoulder pain and improve patients' quality of life.

Background: Inhalation of hydrogen gas (H₂) as an antioxidant supplement may alleviate exercise-induced oxidative damage and protect post-exercise hydrogen peroxide signaling, which may help mediate beneficial exercise adaptation. The aims of this study were to determine the effects of H₂ inhalation on plasma nitric oxide (NO) level and its synthesis precursor in professional athletes.

Methods: A randomized, placebo-controlled, double-blind, crossover trial was conducted with professional male rugby players for 3 weeks. Participants underwent 1 week of H₂ supplementation and 1 week of placebo treatment prior to daily sessions of high-intensity exercise training, separated by 1 week of low-intensity training as a washout.

Results: Two-way (supplementation and time) repeated-measures analyses of variance showed that NO, L-arginine, and tetrahydrobiopterin levels in the H₂ inhalation group were significantly higher than those in the placebo group after exercise (D6) and remained higher after 24 h of rest (D7). Levels of hydroxydeoxyguanosine and interleukin 6 were lower in the H₂ inhalation week than in the placebo week on D6 and D7. In addition, total antioxidant levels were significantly higher with H₂ inhalation than with placebo.

Significance: These results suggest that H₂ inhalation helps to maintain NO signaling after exercise and to alleviate inflammation and oxidative stress induced by high-intensity exercise training in professional athletes.

Heilongjiang Province has the third largest bee population in China, producing over 2,000 tons of beeswax waste (BW) each year. Most of this BW is discarded or burned. Therefore, we urgently need to find sustainable applications of BW. Pleurotus ostreatus mushrooms, commonly referred to as oyster mushrooms, are cultivated for both food and medicine. The substrate used to grow P. ostreatus mushrooms often contains wheat bran as a nitrogen source. The goal of this study was to explore the feasibility of substituting this wheat bran with BW to cultivate P. ostreatus mushrooms. Five treatments were established, with BW making up 0%, 3%, 5%, 7%, and 9% of the total substrate, and the effects on the mycelial growth and development, biological efficiency (BE), and yield were evaluated along with changes in the chemical biomass composition of the fruiting bodies. Adding BW increased the number of days needed for primordia initiation and the number of days between flushes of P. ostreatus mushrooms. With increasing BW, the total fresh weight of P. ostreatus mushrooms first increased and then decreased. The 5% BW treatment resulted in the highest yield and biological efficiency (BE) of 1,478.96 ± 9.61 g bag^-1 and 92.43 ± 0.60%, respectively, which exceeded the values of the control by 4.14% (control: 1,420.15 ± 9.53 g bag^-1 and 88.76 ± 0.60%, respectively). The 5% BW treatment also resulted in the highest mushroom crude protein content (23.47 ± 0.18 g 100 g^-1), which was 28.18% higher compared with the control (18.31 ± 0.05 g 100 g^-1). The 9% BW treatment resulted in the highest crude polysaccharide content (10.33 ± 0.76 g 100 g^-1), which was 2.42-fold that of the control (4.26 ± 0.30 g 100 g^-1). This study suggests that BW could serve as an effective source of nitrogen to cultivate P. ostreatus. BW is a promising, cost-effective, and efficient additive to mushroom substrate, improving the yield and quality of P. ostreatus mushrooms while providing a sustainable use for an otherwise difficult to dispose of waste product.

The present study aimed to characterize the chromosome features of cherry (Prunus pseudocerasus Lindl.) germplasm in Guizhou Province, China, in order to facilitate the selection and breeding programs of this economically and ornamentally valuable species. The stem tip chromosome preparation technique was employed for ploidy identification and karyotype analysis, and the results were further validated by flow cytometry. The findings revealed that the 28 cherry accessions from Guizhou province exhibited a chromosomal base of x = 8, comprising 19 tetraploid and nine hexaploid individuals. Karyotype analysis showed two chromosome types, "m" and "sm," with the longest chromosome/shortest chromosome (Lc/Sc) ranging from 1.6 to 2.65, the mean arm ratio (MAR) varying from 1.15 to 1.56, and index of the karyotypic asymmetry (As.K) ranging from 53.74 to 61.6. Three karyotype types, "1A," "1B," and "2B," were identified among the studied accessions. The most evolutionarily advanced accession was HZ152, while DCZC27 represented the most primitive karyotype. This study expands the ploidy database of Chinese cherry and provides valuable information for the conservation and utilization of cherry germplasm resources in Guizhou province.