PeerJ最新文献

{"title":"Late Pleistocene pelagic gastropods of southern Taiwan: paleobiodiversity, first fossil records, and regional affinity.","authors":"Diana Osipova, Chien-Hsiang Lin","doi":"10.7717/peerj.21046","DOIUrl":"https://doi.org/10.7717/peerj.21046","url":null,"abstract":"<p><p>Holoplanktonic gastropods (pteropods and heteropods) are major components of modern Indo-West Pacific (IWP) plankton, yet their fossil record in this region remains sparse. Expanding the spatial and temporal coverage of fossil data is essential for reconstructing dispersal pathways of pelagic fauna within the IWP and understanding the origins of present-day diversity. Here, we describe a newly discovered Late Pleistocene assemblage of pelagic gastropods from southern Taiwan. The assemblage comprises 14 pteropod and eight heteropod taxa, most representing the first fossil records of holoplanktonic gastropods from Taiwan. We also evaluate variation in paleobiodiversity between depositional environments of the Szekou Formation. Species richness and density do not differ significantly between restricted and open lagoon settings, contrasting with patterns reported for benthic bivalves. To place these findings in a broader context, the newly reported assemblages were analyzed together with other Pleistocene assemblages across the IWP region. Only weak geographic and temporal separation was detected, suggesting a relatively cosmopolitan community composition in subtropical waters during the Pleistocene, likely reflecting low temperature variability despite glacial-interglacial cycles. Indicator species analysis further suggests a later arrival at higher latitudes for the pteropods <i>Telodiacria quadridentata</i> and <i>Heliconoides inflata</i>, which show associations with late Pleistocene sites, whereas <i>Styliola subula</i> displays a distribution resembling its modern range, being most closely associated with assemblages from Taiwan and southern Japan.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"14 ","pages":"e21046"},"PeriodicalIF":2.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13138300/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147841455","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 risk scoring model for lung squamous cell carcinoma based on epithelial-mesenchymal transition-related genes: an integrative analysis of prognosis and immune infiltration characteristics.","authors":"Anqi Zhang, Jinping He, Qiang Lin","doi":"10.7717/peerj.21117","DOIUrl":"https://doi.org/10.7717/peerj.21117","url":null,"abstract":"<p><strong>Background: </strong>Despite expanding therapeutic options, the prognosis of lung squamous cell carcinoma (LUSC) remains poor. Immune checkpoint inhibitors benefit only a subset of patients, and epithelial-mesenchymal transition (EMT) has been implicated in invasion, metastasis, treatment resistance, and immune heterogeneity. Therefore, EMT-related biomarkers may offer improved risk stratification.</p><p><strong>Aim: </strong>To identify differentially expressed EMT-related genes (DEEMTGs) in LUSC, construct an EMT-based prognostic signature, and evaluate its associations with the tumor microenvironment (TME), tumor mutational burden (TMB), and tissue-level expression patterns.</p><p><strong>Methods: </strong>The Cancer Genome Atlas (TCGA) RNA-seq and clinical data were analyzed to obtain DEEMTGs. A prognostic model was built using LASSO and multivariable Cox regression. Survival performance was assessed <i>via</i> Kaplan-Meier, ROC, and Cox analyses. Immune infiltration (CIBERSORT), stromal/immune scores (ESTIMATE), and TMB were compared between risk groups. Exploratory immunohistochemistry (IHC; <i>n</i> = 8) provided orthogonal expression validation.</p><p><strong>Results: </strong>A total of 1,651 DEEMTGs were identified, and a six-gene signature (GAB2, ALDOA, PCDHA3, TMEM92, ERH, IRS4) was established. The risk score independently predicted overall survival and corresponded to distinct TME patterns: low-risk tumors showed higher CD8⁺ T cells, activated CD4⁺ memory T cells, and naïve B cells, whereas high-risk tumors had more resting CD4⁺ memory T cells and M0 macrophages. TMB differences were nonsignificant. IHC provided directional protein-level support while acknowledging transcript-protein variability.</p><p><strong>Conclusion: </strong>We developed a biologically interpretable EMT-based prognostic model that stratifies survival and reflects immune-microenvironment heterogeneity in LUSC. Larger, stage-balanced and immunotherapy-treated cohorts are needed to further validate its clinical utility.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"14 ","pages":"e21117"},"PeriodicalIF":2.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13138313/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147841371","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":"Universes within universes: microbiome diversity associated with different body parts of the sand lizard (<i>Lacerta agilis</i>).","authors":"Joanna Michalska-Madej, Katarzyna Janik-Superson, Bartłomiej Zając, Mariusz Krupiński, Carl Smith, Michal Seweryn, Alejandro Ibáñez","doi":"10.7717/peerj.21061","DOIUrl":"https://doi.org/10.7717/peerj.21061","url":null,"abstract":"<p><p>The bodies of animals host millions of microbial communities collectively known as the microbiome. The microbiome plays a crucial role in various processes related to the host's health and well-being. Although our understanding of the microbiome's importance to host functioning is growing rapidly, many aspects remain poorly understood. One such aspect is the role of the microbiome in chemical communication. To address this question, we used the sand lizard (<i>Lacerta agilis</i>), a reptile with well-developed chemosensory abilities and commonly distributed in Central Europe. Our first goal was to characterize the bacterial microbiome associated with different body parts potentially involved in chemical signalling (<i>e.g.</i>, femoral glands, cloaca, and skin). Additionally, we examined sex-related differences in the microbiome that could be connected to intraspecific communication. Over two years, a total of 274 samples were collected. Amplicon sequencing of the 16S rRNA V3-V4 region revealed significant variation in microbial diversity across body parts, with the skin hosting the most diverse and balanced communities. In contrast, the cloaca and femoral glands contained less diverse but more specialised assemblages. No differences in microbial diversity between sexes were observed, but the year of sampling was an important factor, suggesting a highly dynamic microbiome in sand lizards. There was minimal overlap in the number of unique operational taxonomic units (OTUs) between body parts, indicating a small core microbiome (∼1% of shared taxa). Sex differences in tissue-specific bacteria were more pronounced in the cloaca, supporting the idea that the cloacal microbiome is highly specialised. Our findings suggest that microbial communities vary significantly among body parts, with strong tissue specificity, indicating that each region provides a distinct ecological niche. This study offers promising directions for future research into how host-associated microbiomes could influence chemical communication in vertebrates.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"14 ","pages":"e21061"},"PeriodicalIF":2.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13138299/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147840339","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":"Two new terrestrial narrow-toed frogs (<i>Niceforonia:</i> Strabomantidae, Anura) from remote unexplored mountains in the Ecuadorian Andes.","authors":"Juan P Reyes-Puig, Mario H Yánez-Muñoz, Miguel Urgilés-Merchán, Zane Libke, Santiago R Ron, Julio C Carrión-Olmedo","doi":"10.7717/peerj.21182","DOIUrl":"https://doi.org/10.7717/peerj.21182","url":null,"abstract":"<p><p>We explore the hidden diversity of the terrestrial frog genus <i>Niceforonia</i>, based on phylogenetic and morphological evidence, we describe two new species. Both species are found in pristine unexplored old-growth forest of the Andean slopes of Ecuador. <i>Niceforonia dracula</i> sp. nov., is only known from its type locality at the base of the iconic Cerro Golondrinas, located in the northwesternmost part of the Andes of Ecuador, Carchi Province. This new species is characterized by the presence of low occipital and dorsolateral folds, pale ventral coloration, greatly enlarged toe discs, and circunmarginal grooves in fingers and toes. <i>Niceforonia quilloturo</i> sp. nov. is known from several nearby localities in the upper Pastaza watershed, and is characterized by slightly enlarged tip in fingers and toes, presence of low occipital folds, plus small white pale pointy warts with dark belly and ventral surfaces. Ventral coloration is sexually dimorphic: dark brown with small white points in females and cream, yellow-orange peppered with small black flecks in males. Phylogenetic evidence is concordant with allopatric distribution in <i>Niceforonia dracula</i> sp. nov. and <i>N. elassodiscus</i>, while most of the taxa on the eastern of the Andes show parapatric distribution patterns, including <i>Niceforonia quilloturo</i> sp. nov., and related <i>Niceforonia peraccai</i>. Additional undescribed taxa are intermixed within <i>Niceforonia nigrovittata</i>, thus future systematic revision of the genus is needed.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"14 ","pages":"e21182"},"PeriodicalIF":2.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13138290/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147841470","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":"Combined effects of species diversity and soil depth heterogeneity on plant functional groups and community productivity.","authors":"Lu Liu, Bohui Cheng","doi":"10.7717/peerj.21225","DOIUrl":"https://doi.org/10.7717/peerj.21225","url":null,"abstract":"<p><p>Fine-scale heterogeneity in soil nutrient availability can enhance plant growth, yet its effect across soil depth remains inadequately understood. Communities with increased species diversity showed varying growth strategies among different plant functional groups to occupy soil niches. However, the interactive effects of soil depth heterogeneity and species diversity on plant functional groups and community productivity remain poorly known. This study aimed to examine whether plant functional groups respond differently to soil depth heterogeneity, whether such heterogeneity modifies interspecific relationships and community productivity, and whether higher species diversity alters plant growth strategies under vertical resource variation. A greenhouse experiment was conducted using twelve common herbaceous species with diverse functional traits and root strategies grown under one homogeneous and two heterogeneous treatments that varied in patch size, crossed with two species diversity levels. Plant species differed in responses to soil depth heterogeneity. Increased soil depth promoted the growth of legumes and forbs and enhanced community productivity. In high-diversity mixtures, forbs accumulated greater aboveground biomass in deeper heterogeneous soils, whereas grasses showed no significant response to soil depth or diversity. Legumes displayed a flexible growth pattern, reducing allocation to deeper layers, which may limit competitive pressure. Higher species diversity strengthened the selection effect in forbs, increasing their proportional contribution and intensifying interspecific competition under soil depth heterogeneity. This study provides experimental evidence for soil-plant interactions driving species coexistence and community productivity. Decreased-scale heterogeneity may also function as a reduced-scale form of habitat fragmentation. Long-term field experiments and multi-dimensional niche analyses are needed to better understand community dynamics across gradients of biotic and abiotic factors.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"14 ","pages":"e21225"},"PeriodicalIF":2.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13138296/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147841385","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":"Construction of nomograms for predicting overall survival and progression-free survival in patients with high-grade serous ovarian carcinoma: a retrospective study.","authors":"Yuping Shan, Kejuan Song, Zhengyi Shan, Fangling Han, Lijun Li, Huijun Chu","doi":"10.7717/peerj.21190","DOIUrl":"https://doi.org/10.7717/peerj.21190","url":null,"abstract":"<p><strong>Background: </strong>The aim of this study was to identify independent prognostic factors and develop predictive nomograms for overall survival (OS) and progression-free survival (PFS) in patients with high-grade serous ovarian carcinoma (HGSOC).</p><p><strong>Methods: </strong>Information on patients primarily diagnosed with HGSOC at the Affiliated Hospital of Qingdao University from June 2008 to June 2018 was extracted. Kaplan-Meier (K-M) analyses were used to generate survival curves. We employed univariate and multivariate Cox regression analyses to determine independent prognostic factors, and prognostic nomograms for OS and PFS were developed.</p><p><strong>Results: </strong>A total of 573 patients were included in the final study. The age at diagnosis, first-visit interval, peripheral blood neutrophil-to-lymphocyte ratio, the immunohistochemical expressions of estrogen receptor and progesterone receptor, and Federation of Gynecology and Obstetrics (FIGO) stage were independent prognostic factors associated with OS and PFS. Additionally, the immunohistochemical expression of Wilms' tumor-1 (WT-1) and neoadjuvant chemotherapy were also related to the OS, whereas the serum carbohydrate antigen 125 (CA125) level, the immunohistochemical expression of CK7, omentum metastasis, and postoperative adjuvant chemotherapy were independent prognostic factors linked to PFS. The area under the time-dependent receiver operating characteristic curve values of the nomograms were higher than those of the FIGO staging system. The calibration curves and decision curve analysis demonstrated the clinical applicability of the nomograms.</p><p><strong>Conclusion: </strong>We developed two new risk stratifications based on the total points of the nomograms. This study could provide a foundation for the development of more accurate predictive models that can assist clinicians in creating individualized treatment plans and improving the prognosis of HGSOC.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"14 ","pages":"e21190"},"PeriodicalIF":2.4,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13135751/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147841481","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":"Androgen promotes oocyte development by upregulating gap junction intercellular communication activity in granulosa cells in mice.","authors":"Yangyang Zhang, Yongyan Hu, Yang Xu, Yanrong Kuai, Sheng Wang, Jiao Yu","doi":"10.7717/peerj.21194","DOIUrl":"https://doi.org/10.7717/peerj.21194","url":null,"abstract":"<p><strong>Background: </strong>Recent studies have highlighted the role of androgen in poor ovarian response (POR). However, the mechanisms by which androgen works, particularly in older POR patients, remain unclear. The study aimed to investigate the effects of androgen on granulosa cells and to explore the underlying mechanisms preliminarily.</p><p><strong>Methods: </strong>Elderly female C57BL/6J mice were treated with various concentrations of dehydroepiandrosterone (DHEA) <i>in vivo</i>. Granulosa cells were exposed to different concentrations of testosterone (T), flutamide (an androgen receptor antagonist, AR antagonist), and GF109203X (a protein kinase C inhibitor, PKC inhibitor) <i>in vitro</i>. Gap junction intercellular communication (GJIC) activity was analyzed using the scrape loading/dye transfer technique.</p><p><strong>Results: </strong>DHEA treatment significantly increased serum DHEA, T, and anti-Müllerian hormone levels, as well as the number of oocytes harvested. Treatment with T within the physiological concentration range significantly increased GJIC activity. These effects of T were partially counteracted by flutamide or GF109203X.</p><p><strong>Conclusions: </strong>Androgen may enhance GJIC activity in granulosa cells <i>via</i> the AR pathway and PKC signaling pathway, an effect associated with improved oocyte development in mice. The findings provide a theoretical basis for the use of androgen pretreatment to improve ovarian response in older POR patients.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"14 ","pages":"e21194"},"PeriodicalIF":2.4,"publicationDate":"2026-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13135750/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147841416","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":"Evaluating the scotopic visual sensitivity of walleye (<i>Sander vitreus</i>) and implications for foraging habitat.","authors":"Trevor D Keyler, Loranzie S Rogers, Thomas R Hrabik, Kelly A Harrington, Allen F Mensinger","doi":"10.7717/peerj.21156","DOIUrl":"https://doi.org/10.7717/peerj.21156","url":null,"abstract":"<p><p>Understanding the physiological limits of visual detection is essential for delineating habitat use in freshwater fishes. Walleye (<i>Sander vitreus</i>), a crepuscular predator with well-documented low-light foraging capabilities, exhibits visual adaptations suited for dim environments. Using electroretinography (ERG), we determined the scotopic spectral sensitivity of adult <i>S. vitreus</i> and modeled their potential visual foraging depth under a range of optical conditions. Peak spectral sensitivity occurred between 500-550 nm, aligning with wavelengths that penetrate mesotrophic systems most effectively. We used ERG-derived irradiance thresholds in combination with the Beer-Lambert light attenuation model to estimate maximum depths for visual detection under solar and lunar illumination across a range of turbidity levels. Results indicate that under daylight conditions, <i>S. vitreus</i> can detect light to depths exceeding 77 m in clear water (kPAR = 0.3) and ~13 m in turbid systems (kPAR = 1.2). Under moonlight, detection is possible to 11.3 and 1.9 m, respectively. These depth estimates exceed commonly reported habitat use, suggesting that vision may remain functional beyond expected depth ranges. These results provide a physiological basis for understanding the depth limits and illumination conditions under which scotopic vision may remain functional in walleye across freshwater systems of varying water clarity (kPAR).</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"14 ","pages":"e21156"},"PeriodicalIF":2.4,"publicationDate":"2026-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13135330/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147819400","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":"Caring for patients with multimorbidity: moral distress and life satisfaction among doctors and nurses in Portugal.","authors":"Filipe Prazeres, Rui Fernandes","doi":"10.7717/peerj.21230","DOIUrl":"https://doi.org/10.7717/peerj.21230","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;The prevalence of multimorbidity (MM), defined as the co-occurrence of two or more chronic conditions in an individual, presents complex challenges for healthcare providers (HCPs). In Portugal, nearly half of the general population experiences MM, intensifying demands on HCPs. Doctors and nurses often encounter fragmented care pathways, inadequate guidelines, and frequent ethical dilemmas, which can lead to moral distress (MD). MD arises when HCPs are unable to act in accordance with their ethical beliefs due to institutional barriers, and it has consequences for well-being and employee tenure. This study aims to examine whether MM-related clinical work and life satisfaction are associated with MD among HCPs who regularly care for patients with MM.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;Cross-sectional study surveyed doctors and nurses employed in hospital and non-hospital healthcare facilities in Portugal between August and October 2024. Data were collected using an anonymous electronic questionnaire including validated instruments: the Portuguese version of Measure of Moral Distress for Healthcare Professionals (MMD-HP) and the Satisfaction With Life Scale (SWLS). Additional sociodemographic and work-related information was gathered, including sex, age, marital status, professional role, workplace setting, number of years working with patients with MM (professional experience), and the number of patients with MM seen per week (clinical workload). Associations were examined using linear multiple regression, with the significance level set at 0.05.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;A total of 340 HCPs participated, mostly women (83.2%), nurses (66.8%), and professionals with more than 10 years of experience caring for patients with MM (75.6%). The median MD (MMD-HP) score was 128 (Q1, Q3: 73, 182); median life satisfaction (SWLS) score was 24 (Q1, Q3: 18, 28). MD was negatively correlated with life satisfaction, indicating that lower life satisfaction was associated with higher MD. Higher MD levels were observed in HCPs under 35 years compared with those over 50 (&lt;i&gt;p&lt;/i&gt; = 0.010). HCPs with more than 10 years of experience caring for patients with MM reported significantly lower MD (&lt;i&gt;p&lt;/i&gt; = 0.022). A higher MM-related clinical workload was also associated with greater MD (&lt;i&gt;p&lt;/i&gt; = 0.003). HCPs currently considering leaving their position due to MD reported significantly higher MD and lower life satisfaction (both &lt;i&gt;p&lt;/i&gt; &lt; 0.0001). In multivariable analysis, MM-related clinical workload and life satisfaction remained significant predictors of MD.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Discussion: &lt;/strong&gt;MD was associated with higher MM-related clinical workload and lower life satisfaction. Younger and less experienced HPCs appeared particularly vulnerable. The reliability of these findings should be interpreted with caution due to the use of composite scores and the observational study design . The results reinforce concerns about the impa","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"14 ","pages":"e21230"},"PeriodicalIF":2.4,"publicationDate":"2026-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13135333/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147819314","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":"Smoking-induced changes in saliva composition and tongue coating.","authors":"Nurul Asyikin Yahya, A'lia N Muhammad, Nur Atikah Hashim, Mohammed Thoriq Abdul Razab","doi":"10.7717/peerj.21228","DOIUrl":"https://doi.org/10.7717/peerj.21228","url":null,"abstract":"<p><strong>Background: </strong>Saliva parameters and tongue coating have global significance because they offer simple, non-invasive indicators of oral and systemic health, helping clinicians and researchers detect disease risk, monitor wellness, and improve early diagnostic strategies across diverse populations.</p><p><strong>Objective: </strong>This study aimed to investigate the effects of smoking on salivary flow rate, pH, buffering capacity, and tongue coating characteristics among adult smokers and nonsmokers.</p><p><strong>Methods: </strong>A cross-sectional study was designed to compare salivary parameters and tongue coating between smokers and nonsmokers. A purposive sampling method was used. The data collected included patients' resting and stimulated saliva pH, saliva buffering capacity, and tongue coating for both smokers and nonsmokers. The inclusion criteria required the absence of systemic illness and medication that affected saliva flow.</p><p><strong>Results: </strong>A total of 78 participants were assessed for unstimulated and stimulated saliva flow, salivary pH, buffering capacity, and tongue coating (thickness, area, and colour). Smokers exhibited significantly reduced buffering capacity (<i>p</i> = 0.002) and increased tongue coating thickness and distribution area (<i>p</i> = 0.008 and <i>p</i> = 0.000, respectively), though saliva flow and pH differences were not statistically significant.</p><p><strong>Conclusion: </strong>These findings indicate that smoking is associated with reduced salivary buffering capacity and increased accumulation of tongue coating. Smoking may therefore represent a modifiable behavioural factor influencing salivary defence mechanisms and oral ecological balance. Integrating tongue coating and saliva analysis into caries risk assessment protocols could support earlier identification of individuals at increased risk.</p>","PeriodicalId":19799,"journal":{"name":"PeerJ","volume":"14 ","pages":"e21228"},"PeriodicalIF":2.4,"publicationDate":"2026-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13135328/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147819218","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}