PeerJ最新文献

{"title":"Effect of hypoxia conditioning on physical fitness in middle-aged and older adults-a systematic review and meta-analysis.","authors":"Fanji Qiu, Jinfeng Li, Liaoyan Gan","doi":"10.7717/peerj.19348","DOIUrl":"https://doi.org/10.7717/peerj.19348","url":null,"abstract":"<p><strong>Background: </strong>Hypoxic conditioning has emerged as a promising intervention for enhancing physiological adaptations. This systematic review and meta-analysis of randomized controlled trials aims to investigate the efficacy of hypoxic conditioning on physical fitness measures in aging populations.</p><p><strong>Methods: </strong>The Embase, PubMed, Cochrane Library, and Web of Science were searched from inception to November 2024 (Prospero registration: CRD42023474570). The Cochrane Evaluation Tool and Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework were used for risk of bias assessment and evidence certainty evaluation. Mean differences (MD) and standardized mean differences (SMD) and 95% confidence intervals (CI) were calculated using the Review Manager software. Subgroup analysis was performed to explore possible associations between the study characteristics and the effectiveness of the intervention.</p><p><strong>Results: </strong>A total of 13 randomized controlled trials (RCTs) with 368 subjects were included in the meta-analysis. High certainty evidence found hypoxic conditioning (HC) significantly improved peak oxygen uptake (VO₂peak) (SMD = 0.31, 95% CI [0.01-0.61]; <i>P</i> < 0.05), while very low to moderate certainty evidence shown that hypoxic conditioning (HC) have not induced greater changes on functional outcomes (SMD = -0.21, 95% CI [-0.66-0.24]; <i>P</i> > 0.05), muscle strength (SMD = -0.19, 95% CI [-0.63-0.26]; <i>P</i> > 0.05), maximal power output (SMD = 0.29, 95% CI [-0.17-0.76]; <i>P</i> > 0.05), VO₂max (SMD = -0.39, 95% CI [-1.12-1.90]; <i>P</i> > 0.05), and exercise workload (MD = -10.07, 95% CI [-34.95-14.80]; <i>P</i> > 0.05).</p><p><strong>Conclusion: </strong>This study suggests that hypoxia conditioning has a greater effect on enhancing VO₂peak compared to equivalent normoxic training in the middle-aged and older population. More high-quality RCTs are needed in the future to explore the optimal oxygen concentration and exercise intensity during hypoxia conditioning.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"13 ","pages":"e19348"},"PeriodicalIF":2.3,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12105624/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144151471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regulation of plant gene expression by tsRNAs in response to abiotic stress.","authors":"Chunmei Li, Jing Zhu, Han Jin, Haotian Feng, Haimin Zhuang, Zijun Du, Guolin Zhu, Haiyang He, Fuyang Ye, Zhaohui Mo, Qingtao Hu, Zhenbang Chen, Kai Liu, Xiaorong Wan","doi":"10.7717/peerj.19487","DOIUrl":"https://doi.org/10.7717/peerj.19487","url":null,"abstract":"<p><strong>Objective: </strong>Transfer RNA-derived small RNAs (tsRNAs) are emerging regulators of gene expression in response to abiotic stress. This review aims to summarize recent advances in the classification, biogenesis, and biological functions of tsRNAs, with a focus on their roles in plant stress responses and the methodologies for investigating these molecules.</p><p><strong>Methods: </strong>We conducted a comprehensive literature search across PubMed, Web of Science, and Google Scholar using keywords such as \"tRNA-derived small RNAs\", \"abiotic stress\", \"plant gene regulation\", and \"RNA sequencing\". Studies were selected based on their relevance to tsRNA biogenesis pathways, stress-responsive mechanisms, and functional validation in plant systems. Classification of tsRNAs was performed according to cleavage site specificity and nucleotide length. Bioinformatic tools and experimental approaches for tsRNA identification, target prediction, and functional validation were evaluated.</p><p><strong>Results: </strong>tsRNAs are categorized into two main types: tRNA-derived stress-induced RNAs (tiRNAs; 29-50 nt) and tRNA-derived fragments (tRFs; 14-40 nt). tiRNAs arise from anticodon loop cleavage by RNase A/T2, while tRFs are generated <i>via</i> Dicer-dependent or -independent pathways. These molecules regulate gene expression at transcriptional, post-transcriptional, and translational levels by interacting with AGO proteins, displacing translation initiation factors, and modulating stress granule assembly. In plants, tsRNAs respond dynamically to abiotic stresses (<i>e.g</i>., drought, salinity, heat), influencing stress signaling pathways and epigenetic modifications. Advanced sequencing techniques (<i>e.g</i>., cP-RNA-seq, RtcB sRNA-seq) and databases (PtRFdb, tRFanalyzer) have facilitated tsRNA discovery and functional annotation.</p><p><strong>Conclusions: </strong>tsRNAs represent a versatile class of regulatory molecules in plant stress biology. Their ability to fine-tune gene expression underpins adaptive responses to environmental challenges. Future research should prioritize standardized methodologies for tsRNA profiling, elucidation of stress-specific biogenesis mechanisms, and exploration of their potential as biomarkers or therapeutic targets for crop improvement. Integrating tsRNA research with systems biology approaches will deepen our understanding of plant resilience mechanisms.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"13 ","pages":"e19487"},"PeriodicalIF":2.3,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12105621/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144151489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of a combined nature-based and audio-based virtual mindfulness intervention on stress and wellbeing of COVID-19 healthcare workers: a randomized controlled trial.","authors":"Polycarpe Bagereka, Rezvan Ameli, Ninet Sinaii, Marcelli Cristine Vocci, Angelina Mangiardi Coulter, Michael Neustedter, Ann Berger","doi":"10.7717/peerj.19109","DOIUrl":"https://doi.org/10.7717/peerj.19109","url":null,"abstract":"<p><strong>Background: </strong>The global COVID-19 pandemic and its subsequent transition to an endemic phase has highly increased psychosocial distress among healthcare workers. This chronic stress may culminate into burnout, which has been associated with impaired patient care and increased medical errors. Exposure to nature-based programs have been shown to reduce levels of perceived stress and promote well-being. However, benefits derived from nature programs can be short-lived. Mindfulness-based interventions represent a promising additive option to enhance benefit. The present study proposes to combine a nature-based program with an audio-based mindfulness intervention to address stress and promote psychosocial-spiritual wellbeing in COVID-19 healthcare workers.</p><p><strong>Methods: </strong>Between June 2021 and October 2023, 78 healthcare workers were randomized into a Nature only group (Nature), a Combined Nature-Mindfulness group (Combined), and a control group (Control), with 19, 16, and 18 subjects completing the study, respectively (23-46 years, mean = 35, SD = 6). The nature program was a three or five-day retreat during which participants engaged in rock climbing, surfing or kayaking. The virtual audio mindfulness intervention was a 10-day program offered online and included mindful breathing, body scan, and loving-kindness meditation. Participants completed self-administered assessments at three or four time points during the study, including at baseline and following study procedures. Assessments included a measure of stress, the Perceived Stress Scale, and a measure of wellbeing, the National Institute of Health Healing Experience of All Life Stressors (NIH-HEALS).</p><p><strong>Results: </strong>The mean baseline Perceived Stress Scale score was 21.2 ± 3.2 in the Combined group, 22.3 ± 2.8 in the Nature group, and 23.2 ± 3.3 in the Control group. Perceived Stress Scale levels did not change following nature-based and mindfulness-based interventions. The mean baseline NIH-HEALS score was 123.1 ± 19.4 in the Combined group, 118.1 ± 17.1 in the Nature group, and 114.3 ± 17.8 in the Control groups. NIH-HEALS scores increased in both the Nature and Combined groups when compared to the Control group. At follow-up, the Combined group maintained improvements in wellbeing when compared to the Nature group.</p><p><strong>Conclusions: </strong>Findings suggest that nature-based programs can be used to improve overall wellbeing among COVID-19 healthcare workers. Additionally, integrating audio-based mindfulness practices to these programs may enhance their benefits. Notably however, these interventions may not effectively reduce perceived stress among COVID-19 healthcare workers. Due to diminished power of the present study, further research is needed to validate and refine the present findings.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"13 ","pages":"e19109"},"PeriodicalIF":2.3,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12105617/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144151474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Early conch morphology of a gigantic Cretaceous ammonoid, <i>Pachydesmoceras denisonianum</i> (Desmoceratidae).","authors":"Ryoji Wani","doi":"10.7717/peerj.19488","DOIUrl":"https://doi.org/10.7717/peerj.19488","url":null,"abstract":"<p><p>Gigantic ammonoids, with conch diameters exceeding 1 m, remain one of the most enigmatic groups of extinct organisms. Their paleoecology has been the subject of ongoing debate, with some uncertainties arising from preservation biases, especially of an early conch. This study focuses on an exceptionally preserved early conch of the giant Cretaceous ammonoid <i>Pachydesmoceras denisonianum</i> from southern India. Conch morphology and the ontogenetic trajectories of constrictions and septal spacings were examined. The results indicate that constrictions were frequently present in the early conch; based on the shell layers observed in the cross-section, these constrictions likely resulted from periods of halted or slowed growth. The common occurrence of constrictions during early ontogeny suggests that <i>Pachydesmoceras</i> lifespan may have been longer than previously assumed. Additionally, the ontogenetic patterns of septal spacing might not reflect these growth halts or slowdowns in the examined species.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"13 ","pages":"e19488"},"PeriodicalIF":2.3,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12105615/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144151468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of lower-leg muscle activation and establishment of muscle activation patterns during single-leg stance under various instability conditions in healthy active subjects: a cross-sectional study.","authors":"Mariana Sánchez-Barbadora, Vicente Alepuz-Moner, Noemi Moreno-Segura, Rodrigo Martín-San Agustín","doi":"10.7717/peerj.19461","DOIUrl":"https://doi.org/10.7717/peerj.19461","url":null,"abstract":"<p><strong>Background: </strong>Balance training exercises are essential for treating and preventing a variety of ankle conditions such as sprains, chronic ankle instability, and muscular weakness. This muscle activation could often be increased using unstable devices. The Blackboard is a new configurable selective instability device, that has the potential to focus directly on desired muscles without overloading others through wooden half cylinders slats joined to a board by a tape in different positions. Depending on the position where they are situated, different stability training could be performed. However, its specific muscle activation patterns remain unknown.</p><p><strong>Methods: </strong>Surface electromyography was used to measure the activation level of six lower-leg muscles (<i>i.e</i>., soleus, gastrocnemius medialis, gastrocnemius lateralis, tibialis anterior, peroneus longus, and peroneus brevis) in a single-leg stance on the floor and on seven Blackboard configurations. Thirty healthy active subjects participated in the study.</p><p><strong>Results: </strong>Multiple differences in muscle activation were observed between conditions and among muscles. Notably, the tibialis anterior and the peroneus showed the greatest differences between conditions and the highest activation levels on the Blackboard. Additionally, forefoot supination and rearfoot eversion configurations induced selective activation of the tibialis anterior and peroneus longus, respectively, highlighting their usefulness for isolating specific muscle contractions.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"13 ","pages":"e19461"},"PeriodicalIF":2.3,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12105616/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144151466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unconscious information processing of table tennis athletes in a masked priming paradigm: an event-related potentials (ERP) study.","authors":"Fanying Meng, Lijiao Chen, Chun Xie, Jiadong Zheng, Ning Chen, Fanghui Qiu, Jiaxian Geng","doi":"10.7717/peerj.19508","DOIUrl":"https://doi.org/10.7717/peerj.19508","url":null,"abstract":"<p><strong>Background: </strong>Unconscious information processing is enhanced among athletes for sports-specific contexts. Whether this enhancement is transferable to general contexts is unknown. This study explored unconscious information processing and brain activity in highly trained table tennis athletes and non-athletes in general contexts.</p><p><strong>Methods: </strong>Twenty table tennis athletes (six females, mean age = 20.38 ± 1.28, mean ± standard error) and 21 aged-matched college students (eight females, mean age = 19.81 ± 1.29) were recruited for this study. Each participant first performed a masked priming task. In this task, a prime stimulus (arrows pointing left or right) was presented, followed by a visual mask (arrows pointing in both directions) and then a target stimulus, the target stimulus consisted of arrows pointing in the same direction as the prime for congruent stimuli or in the opposite direction for incongruent trials, while the P3 component of the event-related potential was simultaneously recorded in the brain. As a control, participants then performed a prime identification task (the subjective threshold test and the objective threshold test) to determine whether they could consciously detect the priming arrows. Reaction times, error rates, P3 latency and P3 peak amplitude were analyzed to examine the unconscious information processing of table tennis athletes in general contexts.</p><p><strong>Results: </strong>Participants responded with the direction of the target arrow and were not consciously aware of the priming stimulus. Athletes responded faster in comparison of non-athletes. Athletes and non-athletes responded faster and committed fewer errors in incongruent <i>vs</i>. congruent conditions. In addition, the years of table tennis training were negatively correlated with the magnitude of negative compatibility effect. Both groups displayed longer P3 latencies, a measure of inhibitory control, in the incongruent <i>vs</i>. congruent trials. However, athletes displayed higher P3 peak amplitudes, reflecting larger attention resource input, and longer P3 latencies than non-athletes in central brain sites.</p><p><strong>Conclusion: </strong>Unconscious information processing among table tennis athletes is not prominent in general contexts, but may be limited to the sports-specific context or more complex cognitive tasks.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"13 ","pages":"e19508"},"PeriodicalIF":2.3,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12105618/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144151492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phylogeographic analysis of long-legged bats, <i>Macrophyllum macrophyllum</i>, with notes on roosting behavior and natural history.","authors":"Guilherme S T Garbino, Thiago Borges Fernandes Semedo, Juliane Saldanha, Daniela Cristina Ferreira, Rogerio Vieira Rossi, Maria Nazareth Ferreira da Silva, Burton K Lim","doi":"10.7717/peerj.19432","DOIUrl":"https://doi.org/10.7717/peerj.19432","url":null,"abstract":"<p><p>The long-legged bat (<i>Macrophyllum macrophyllum</i>) is widely distributed in the continental Neotropics, but poorly known because it is not commonly caught in mist nets. Available data suggest that this species is closely associated with water where it forages for insect prey. We compiled the first comprehensive molecular dataset assembled for the species, spanning its entire distributional range to investigate if the phylogeography of this monotypic genus is associated with the hydrographic drainage, ecosystem regions, or genetic clustering in Central and South America. To survey under sampled areas, fieldwork was conducted in the Brazilian Pantanal and Cerrado targeting the search for riverine roost sites of <i>Macrophyllum</i>. A literature review was also done to summarize roosting information for the species. New sequences of the mitochondrial cytochrome <i>b</i> gene were generated for tissue samples from Brazil and in museum collections. Phylogenetic trees were constructed using both maximum likelihood and Bayesian inference methods and a haplotype network was used to analyze population structure. Our phylogenetic results identified five geographic lineages of <i>Macrophyllum</i> from (1) the western Cerrado, (2) eastern Cerrado and Pantanal, (3) Guianas, (4) Amazonia, and (5) Central America. However, the haplotype network in conjunction with the genetic clustering identified four populations with the eastern Cerrado and Pantanal grouping with the Guianas and the eastern part of Amazonia. The fieldwork in the Cerrado and Pantanal along with the literature review identified that about half of the roost sites for the long-legged bats were drainage culverts. There is geographic structuring in the mitochondrial data of <i>Macrophyllum</i> with Central America, western Cerrado, Pantanal, Guianas, and eastern Ecuador reciprocally monophyletic and well differentiated populations. However, the under sampled eastern Amazonia is poorly resolved in relation to the other areas. The long-legged bats seem to be relatively adaptable to certain levels of human disturbance and landscape development with man-made drainage culverts commonly used as roosting sites. Increased biodiversity surveys of bats in central Brazil are needed to fill in distributional gaps, such as the lower Amazon River basin, to resolve phylogeographic patterns of <i>Macrophyllum</i> in South America and better understand the potential of cryptic species in this monotypic genus.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"13 ","pages":"e19432"},"PeriodicalIF":2.3,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12105620/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144151482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A scoping review of tropical pioneer trees' roles for restoration and conservation management: <i>Harungana madagascariensis</i> (Hypericaceae) a widespread African species as a model.","authors":"François M M P Baguette, Cláudia Baider, F B Vincent Florens","doi":"10.7717/peerj.19458","DOIUrl":"https://doi.org/10.7717/peerj.19458","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Globally, biodiversity is declining rapidly, including tropical forests ecosystems in particular. To stop and reverse this trend, governments worldwide signed up to international agreements and initiatives, but success to date has been limited. In this context, reviewing pioneer trees' ecology, particularly the most widespread species, can help gauge their pros and cons and guide their judicious use for cost-effective ecological restoration projects.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Objectives: &lt;/strong&gt;This study aims to review the potential of pioneer tree species for biodiversity conservation and forest restoration and identify eventual knowledge gaps, using a widespread species from Africa, &lt;i&gt;Harungana madagascariensis&lt;/i&gt; Lam. (Hypericaceae), as a model. Our specific objective was to synthetize information on the distribution and habitat of &lt;i&gt;H. madagascariensis&lt;/i&gt;; its documented interspecific ecological interactions; and its potential for forest restoration.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methodology: &lt;/strong&gt;A scoping review was conducted using multiple databases to identify relevant papers, supplemented by the Global Biodiversity Information Facility database (GBIF) to extract distribution records of &lt;i&gt;H. madagascariensis&lt;/i&gt;. Following the PRISMA screening process for scoping reviews, 398 publications and 4,379 records from GBIF (2023) were used in the final analysis out of a total of 1,159 unique articles and 5,230 records originally retrieved.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;We show that &lt;i&gt;H. madagascariensis&lt;/i&gt;, which is native to tropical Africa, Madagascar, and some islands of the Mascarenes, is a key component of young secondary forests, wetland areas, and grasslands. At least 125 species were found to interact directly with &lt;i&gt;H. madagascariensis&lt;/i&gt;, including through commensalism, mutualism, and herbivory. It is recognized as a tool for restoration regionally, and considered as invasive in Australia where it has been introduced and, by some, in Mauritius where it is native. The benefits it provides for restoration include its capacity to improve degraded soil fertility, its ability to compete with invasive alien species mostly due to its heliophilous and fast-growing nature, and its good nurse tree potential along with its ecological interactions that support numerous species including threatened ones.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion: &lt;/strong&gt;The widespread African pioneer tree &lt;i&gt;H. madagascariensis&lt;/i&gt; plays a critical role in vegetation dynamic and holds great potential for fostering forest restoration and biodiversity conservation in its range of nearly 13 M km&lt;sup&gt;2&lt;/sup&gt;. Its greater use in restoration projects could significantly accelerate ecological restoration, decrease its costs, and increase benefits to biodiversity, leading to larger areas being restored, contributing effectively to national and international objectives. However, a number of aspects deserve further studies, such as the species' role in multitrophic in","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"13 ","pages":"e19458"},"PeriodicalIF":2.3,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12105622/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144151459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improving the cultivated rice Sakha104 (<i>Oryza sativa</i> L.) using gene pools of some relative wild species.","authors":"Walid H Elgamal, Mostafa M Elshenawy, Samah M Abdelkhalek, Dayun Tao, Jiawu Zhou, Jing Li, Medhat Rehan","doi":"10.7717/peerj.19453","DOIUrl":"https://doi.org/10.7717/peerj.19453","url":null,"abstract":"<p><strong>Background: </strong>Rice (<i>Oryza sativa</i> L.) is considered a staple food for one-half of the world's population. The yield of rice must increase to keep up with the world's population growth. Blast disease (caused by <i>Magnaporthe oryzae</i>) is biotic stress that threatens rice production and can result in yield losses up to 70%.</p><p><strong>Methods: </strong>The present research attempted to widen the genetic base of Egyptian cultivated rice Sakha 104 (<i>Oryza sativa</i>), using gene pools from certain relative wild ancestors, in order to cope with blast infection and grain yield. Crossing Sakha 104 × <i>O. glaberrima</i> and Sakha 104 × <i>O. glumaepatula</i> resulted in selecting 20 genotypes. The produced genotypes and the Egyptian cultivar Sakha 104 were assessed for days to heading (HD), plant height (PH), number of tillers/plant (NTP), panicle weight (PW), 1,000-grain weight (TGW), grain yield/plant (GYP), spikelet fertility (SF), blast reaction (BR), hulling percentage (HP), milling percentage (MP), head rice (HR), and amylose content (AC).</p><p><strong>Results: </strong>Line AS-AF L3 had the earliest heading date, whereas AS-AF L6 revealed the lowest and the best values in plant height. In addition, line AS-AM L9 generated the most tillers/plant and the heaviest panicle weight. For TGW, AS-AM L3 showed the uppermost value, while AS-AM L4 recorded the highest percentage in spikelet fertility and high productivity of grain yield/plant. Furthermore, all assessed genotypes presented a unity (the value of 1) across the two seasons of evaluation in blast reaction. Grain quality criteria such as hulling, milling percentages and head rice assigned to AS-AF L10 and AS-AM L3, whereas AS-AF L2 possessed the lowest values in amylose content. Moreover, genetic variance (GV), phenotypic variance (PV), genotypic and phenotypic coefficient variations (GCV and PCV) were estimated for all traits with higher PV and PCV than GV and GCV, respectively. Heritability in broad sense (h2b%) disclosed high heritability values for heading date (0.85), plant height (0.925), grain yield/plant (0.95), 1,000 grains weight (0.92), blast reaction (0.935), head rice (0.97) and amylose content (0.90), reflecting strong genetic control of these traits. Eventually, broadening the genetic background of Sakha 104 cultivar against blast infection will minimize its impact and enhance the food security in Egypt.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"13 ","pages":"e19453"},"PeriodicalIF":2.3,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12105619/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144151478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genomic profiling of <i>Streptococcus agalactiae</i> (Group B <i>Streptococcus</i>) isolates from pregnant women in northeastern Mexico: clonal complexes, virulence factors, and antibiotic resistance.","authors":"Jose Manuel Vazquez-Guillen, Gerardo C Palacios-Saucedo, Lydia Guadalupe Rivera-Morales, Amilcar Caballero-Trejo, Aldo Sebastian Flores-Flores, Juan Manuel Quiroga-Garza, Rocio Alejandra Chavez-Santoscoy, Jesus Hernandez-Perez, Silvia Alejandra Hinojosa-Alvarez, Julio Antonio Hernandez-Gonzalez, Maurilia Rojas-Contreras, Ricardo Vazquez-Juarez, Ramon Valladares-Trujillo, Cesar Alejandro Alonso-Tellez, Joaquin Dario Treviño-Baez, Miguel Angel Rivera-Alvarado, Reyes S Tamez-Guerra, Cristina Rodriguez-Padilla","doi":"10.7717/peerj.19454","DOIUrl":"10.7717/peerj.19454","url":null,"abstract":"<p><strong>Background: </strong><i>Streptococcus agalactiae</i> (Group B <i>Streptococcus</i>, GBS) is an important pathogen associated with neonatal sepsis, pneumonia, and meningitis, which can be transmitted from colonized pregnant women to their newborns. This study aimed to determine the prevalence and characterize the genomic features of <i>S. agalactiae</i> isolates from pregnant women attending a referral hospital in Northeastern Mexico.</p><p><strong>Methods: </strong>Vaginal-rectal swabs were collected from pregnant women during routine prenatal care between April 2017 and March 2020. Whole-genome sequencing was conducted to determine sequence type (ST), clonal complex (CC), capsular polysaccharide (Cps) genotype, virulence factors, and antibiotic resistance genes through comparative genome analysis.</p><p><strong>Results: </strong><i>S. agalactiae</i> colonization was detected in 51 (2.7%) of 1,924 pregnant women. The most common STs were ST8 (23.5%) and ST88 (15.7%). Cps genotyping showed high concordance between serological and molecular methods. Genes conferring resistance to tetracyclines (<i>tetM</i>, 60.1%) and macrolides (<i>mreA</i>, 100%) were identified. Key virulence factor genes, including <i>cylE</i>, <i>bca</i>, and <i>scpB</i>, were present in over 90% of the isolates.</p><p><strong>Conclusion: </strong>Although GBS colonization prevalence was low, genomic analysis revealed the genetic diversity of <i>S. agalactiae</i> in Northeastern Mexico, emphasizing the importance of molecular techniques for epidemiological surveillance and infection control.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"13 ","pages":"e19454"},"PeriodicalIF":2.3,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12103846/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144142511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}