title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=7 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Neutrophil-to-lymphocyte ratio: a potential supportive marker for elderly community-acquired bloodstream infections—a retrospective study link: https://peerj.com/articles/20449 last-modified: 2025-12-08 description: BackgroundExploring the value of the neutrophil/lymphocyte ratio (NLR) as a potential supportive marker in community-acquired bloodstream infection in elderly patients.MethodsBy reviewing the data of inpatients in Xuanwu Hospital of Capital Medical University from January 2012 to December 2021, a total of 58 elderly patients with community-acquired bloodstream infection and 174 inpatients without infection during the same period, matched for age, sex, and concomitant diseases, were included. Clinical data were collected and analyzed statistically.ResultsThere were no significant differences in age, sex, and concomitant diseases between the infected and non-infected groups. Multivariate regression analysis showed that only increased NLR among leukocyte indexes was a risk factor for bloodstream infections. The sensitivity, specificity, and area under the curve (AUC) of increased NLR to support the diagnosis of community-acquired bloodstream infections in the elderly were 0.72, 0.99, and 0.95; the optimal cut-off value is 8.0.ConclusionThe increase in NLR was superior to the rise of traditional white blood cell and neutrophil counts. Thus, NLR can be used as an indication for the early diagnosis of community-acquired bloodstream infection in the elderly. The optimal cutoff value of NLR for supporting the diagnosis of community-acquired bloodstream infections in elderly patients was determined to be 8.0. When NLR exceeds this threshold (> 8.0), it serves as a clinical alert for community physicians, indicating a significantly elevated probability of elderly patients developing community-acquired bloodstream infections. creator: Peijuan Li creator: Jiulin Zhang creator: Kun Chen creator: Qianqian Pei creator: Mengxi Ding creator: Chunmei Wang uri: https://doi.org/10.7717/peerj.20449 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Li et al. title: Validation of an aspiration risk prediction model for Parkinson’s disease based on nomogram: a single-center study link: https://peerj.com/articles/20443 last-modified: 2025-12-08 description: ObjectiveThis study aims to develop and validate a predictive model for aspiration risk in patients with Parkinson’s disease (PD).MethodsA total of 160 inpatients with PD were enrolled (December 2022 to December 2023) from the Neurology Department of the Affiliated Drum Tower Hospital. Of 33 candidate variables, univariate analysis and Least Absolute Shrinkage and Selection Operator (LASSO) logistic regression were used to identify key predictors and construct a clinical nomogram. Model discrimination and calibration were assessed using receiver operating characteristic (ROC) curves and calibration plots.ResultsUnivariate analysis and LASSO regression reduced the 33 variables to four core predictors: history of choking cough (odds ratio (OR) = 11.427; 95% confidence interval (CI) [2.187–59.709]), abnormal water-swallowing test results (OR = 4.262, 95% CI [1.496–12.140]), reduced facial expression (OR = 2.929, 95% CI [1.055–8.134]), and Barthel Index (OR = 0.972, 95% CI [0.950–0.995]). The area under the curve (AUC) values of the model were 0.882 (optimism-adjusted) and 0.950 for the training and testing sets, respectively. Calibration and decision curve analyses further validated the high performance and clinical utility of this model.ConclusionThis nomogram effectively stratified aspiration risk in patients with PD, facilitating earlier detection and intervention. Future studies including more clinical variables and larger multicenter cohorts are required to enhance the predictive accuracy and generalizability of the model. creator: Yan Yan Xu creator: Yun Wei creator: Ling Sha uri: https://doi.org/10.7717/peerj.20443 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Xu et al. title: Effects and potential mechanisms of iron metabolism on vascular calcification link: https://peerj.com/articles/20392 last-modified: 2025-12-08 description: Vascular calcification (VC) is a prevalent pathological manifestation of cardiovascular and cerebrovascular diseases, and is an active, multifactor-regulated pathological process. Iron is an essential metal that maintains cellular and body functions, and its metabolic homeostasis plays a complex and crucial dual role in the development of VC. This study, based on a comprehensive analysis of numerous studies, revealed that the effect of iron on VC has a significant dose-dependent relationship: physiological concentrations or moderate amounts of iron exert protective effects by enhancing antioxidant defenses, thereby inhibiting the osteogenic phenotype transformation and apoptosis of vascular smooth muscle cells; conversely, iron overload strongly drives VC by inducing oxidative stress, ferroptosis, and pro-inflammatory responses. These findings highlight the importance of maintaining iron homeostasis. Intervention strategies targeting iron metabolism (such as iron-based phosphate binders to correct iron deficiency and iron chelators to alleviate iron overload) have potential clinical value for the prevention and treatment of VC. In summary, this review provides a novel perspective on the diagnosis and treatment of VC, and future studies need to further explore its mechanisms and conduct rigorous clinical validation to manage iron metabolism as a novel approach for personalized prevention and treatment of VC. creator: Hongyu Wang creator: Yanqiu Song creator: Qin Qin uri: https://doi.org/10.7717/peerj.20392 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Wang et al. title: Variations in length of stay among surviving preterm infants admitted to neonatal intensive care units in Shenzhen, China link: https://peerj.com/articles/20344 last-modified: 2025-12-08 description: BackgroundThe global preterm birth rate is currently around 10%, making it a major contributor to both neonatal mortality and long-term health complications. Length of stay (LOS) in hospital is a key metric when assessing the quality of medical care for preterm infants. Therefore, a comprehensive analysis of LOS in preterm infants, along with the identification of associated risk factors, is essential in order to improve clinical outcomes and optimize healthcare strategies.ObjectiveThis study examined the LOS and total hospitalization costs of preterm infants admitted to neonatal intensive care units (NICUs) in three hospitals in China . The study also investigated the factors affecting the LOS and total hospitalization costs of surviving preterm infants admitted to NICUs.MethodsThis is a retrospective analysis of preterm infants born between January 2020 and December 2023 who were admitted to one of three participating tertiary care centers within one week after birth. Baseline characteristics, LOS, and hospitalization costs were described and summarized. Generalized linear models were utilized to estimate adjusted associations between LOS and various factors.ResultsThis study included 2,887 preterm infants. The median total LOS was 10 days (interquartile range (IQR): 7–20), and the median total hospitalization cost was RMB ¥16,287.3 (IQR: ¥10,541.9–32,342.3). Both LOS and hospitalization costs decreased significantly with increasing gestational age (GA) and birth weight (BW). Infants at 34 to 36+6weeks’ gestation had a 68% shorter LOS compared to those at <28 weeks (relative risk (RR) 0.32, 95% confidence interval (CI) [0.27–0.38]). Similarly, infants with BW ≥ 2,500 g had a 54% shorter LOS than those <1,000 g (RR 0.46, 95% CI [0.39–0.54]).ConclusionLow GA, low BW, maternal hypertension, low Apgar score , small for GA (SGA), bronchopulmonary dysplasia (BPD), sepsis, and extrauterine growth retardation were associated with prolonged hospitalization. creator: Dandan Rao creator: Zhangbin Yu creator: Rongtian Liu creator: Rui Wang creator: Xin Guo creator: Huiying Tu creator: Ping Jiang creator: Jing Zhang creator: Jinxing Feng creator: Linying Yang creator: Yuqin Yan creator: Jiebo Liu uri: https://doi.org/10.7717/peerj.20344 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Rao et al. title: In situ mechanical behavior of mineralized collagen fibrils in murine cortical bone is altered by aging and disuse link: https://peerj.com/articles/20313 last-modified: 2025-12-08 description: Mineralized collagen fibrils (MCFs) are the fundamental building blocks of bone, determining its mechanical properties. Aging and disuse are known to impair bone mechanics, but their specific effects on the nanoscale, in situ mechanical behavior of MCFs remain poorly understood. The present study utilized a murine model involving adult and aged mice, with a subset from each age group subjected to disuse through hindlimb unloading (n = 6). To investigate the in situ nanomechanical response of bone, murine tibiae were tensile-loaded within a custom-made axial loading device while being simultaneously scanned with atomic force microscopy (AFM). The bone surface was partially demineralized to expose the collagen fibrils. High-resolution AFM imaging in tapping-mode was then employed to quantitatively assess the morphological changes and nanomechanical properties of MCFs throughout the bone’s elastic deformation process. In the adult murine tibia, the initial response to load was characterized by fibril reorientation and an increase in the in situ elastic modulus of MCFs, indicating stretching. It was followed by a sliding phase between adjacent fibrils. In contrast, the aged bone exhibited fibril sliding at the onset of loading, accompanied by a gradual decrease in the elastic modulus of MCFs. The nanomechanical alterations induced by disuse were more pronounced in aged mice compared to adults. The present findings demonstrate that aging and disuse significantly alter the nanoscale deformation mechanisms of bone, shifting the response from fibril stretching to predominant sliding. It provides novel evidence for a unique, age-dependent deformation mechanism at the fibrillar level, enhancing the current understanding of how aging and disuse impair bone quality and mechanics. creator: Fan Li creator: Fa Liu creator: Chenxi Ren creator: Shuyang Zhang creator: Zhe Wang creator: Pengfei Yang uri: https://doi.org/10.7717/peerj.20313 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2025 Li et al. title: Exploring probiotic awareness, perceptions, and practices in the Saudi population: a cross-sectional study link: https://peerj.com/articles/20490 last-modified: 2025-12-05 description: BackgroundProbiotics are composed of trillions of microorganisms, mainly located in the gastrointestinal tract (GIT), which play vital roles in digestion, immunity, and overall well-being. They help maintain gut health and prevent various gastrointestinal disorders. Despite the widespread use of probiotics in developed countries, such as North America and Western Europe, little is known about their use in Saudi Arabia. This study aimed to assess the knowledge, attitudes, and factors influencing probiotic awareness among the Saudi public to support healthier dietary choices.MaterialsA cross-sectional study using a structured questionnaire titled “Public Knowledge and Perception of Probiotics” was conducted among Saudi residents aged 18 years and older from July to October 2024. With a type I error rate of 5% (α = 0.05) and 80% power, the required sample size was 269; ultimately, 286 individuals participated in the study. Data were analyzed using the Statistical Package for the Social Sciences version 27 (IBM).ResultsThe majority of the 286 participants were female (79%) and over 30 years old (54.9%). Awareness of probiotics was moderate (mean score: 5.2; 65%), with yogurt being the most recognized source (95%). Participants generally had positive perceptions (mean score: 3.74 ± 0.60), although barriers such as limited knowledge (56.2%) and high cost (3.28 ± 1.09) were reported. Probiotic use was noted in 54.5% of the respondents, with 71.2% preferring natural sources. Usage was significantly associated with demographic factors, including age ($\chi^2$χ2 = 15.251, P < 0.001), education level ($\chi^2$χ2 = 18.787, P < 0.001), marital status ($\chi^2$χ2 = 9.825, P = 0.002), and monthly income ($\chi^2$χ2 = 8.548, P = 0.014).ConclusionWhile awareness and positive perceptions of probiotics are growing among the Saudi population, challenges such as knowledge gaps, affordability, and limited advertising persist. To promote probiotic use and improve public health outcomes, it is crucial to enhance public health education through schools and community programs, improve affordability via supportive health policies, and encourage greater involvement of healthcare professionals in providing probiotic-related guidance. creator: Basmah F. Alharbi uri: https://doi.org/10.7717/peerj.20490 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2025 Alharbi title: Bond strength between layering ceramic and zirconia core: influence of various surface conditioning of zirconia link: https://peerj.com/articles/20480 last-modified: 2025-12-05 description: ObjectiveIt is recommended to apply various surface modification techniques to improve the mechanical and chemical interaction between zirconia core and veneering ceramic. Therefore, the objective of this in-vitro study was to evaluate and compare the effects of various surface treatments over the zirconia core on the shear bond strength (SBS) between layering ceramic and zirconia core.MethodsA total of 90 zirconium oxide (Cercon, Degudent GmbH, Hanau-Wolfgang, Germany) specimens were prepared with standardized dimensions (10 mm × 10 mm × 5 mm). The specimens were randomly divided into six groups of 15 specimens each (Control group-no surface treatment; Sandblasting with 25 µm Al2O3; Sandblasting with 50 µm Al2O3; Sandblasting with 110 µm Al2O3; Etching with hydrofluoric acid (9.5%); Surface treatment using Zirface (nano layer etching technology for enhanced bonding strength of zirconia). All specimens were veneered with fluorapatite glass-ceramic (5 mm × 5 mm × 5 mm) using a custom silicone mold, sintered in a calibrated porcelain furnace, and verified with a digital caliper. Following veneering, the samples were embedded in self-curing acrylic resin within polyvinyl chloride molds and immersed in distilled water at 37 °C for 24 hours to simulate intraoral conditions. Using universal testing machine, specimens were tested for SBS. Analysis of variance (ANOVA) and Tukey’s-test were used for statistical analysis (P ≤ 0.05). Surface topography of the surfaces treated and after debonding were examined using scanning electron microscope (SEM) and failure mode of different groups was also noted.ResultsThe application of Zirface to the zirconia core had the highest mean SBS value (26.56 ± 1.25 MPa), followed by the hydrofluoric acid only group (23.42 ± 0.94 MPa). The control group with no surface treatment showed the least SBS values. While the groups with surface treatments of 25 and 50 aluminum oxide (Al2O3) sandblasting showed SBS values of 17.16 ± 0.48 and 18.06 ± 0.89, respectively, with no significant difference (p > 0.05) between the SBS values of the two groups. However, the sandblasting with 110 Al2O3 particles over the zirconia core surface showed higher SBS values (20.53 ± 1.14) as compared to the 25 and 50 Al2O3 particles.ConclusionThe study found that the shear bond strength between zirconia and veneering ceramic is significantly influenced by the surface treatment used, with nano-layer etching and hydrofluoric acid etching enhancing adhesion, and larger alumina particles enhancing bonding durability. creator: Abdulaziz A. AlHelal creator: Syed Rashid Habib creator: Saleh Alyousef creator: Nawaf Alhamzah creator: Meshal Alqahtani creator: Abdulaziz Alqahtani uri: https://doi.org/10.7717/peerj.20480 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 AlHelal et al. title: Effect of major ozone autohemotherapy in fibromyalgia syndrome: a retrospective study link: https://peerj.com/articles/20475 last-modified: 2025-12-05 description: BackgroundFibromyalgia Syndrome (FMS) is a multifaceted chronic disease characterized by widespread musculoskeletal pain, fatigue, sleep disturbances, cognitive dysfunction, and increased sensitivity to stimuli, commonly referred to as central sensitization. Ozone therapy is currently used in the treatment of many chronic diseases by creating controlled oxidative stress. This study aimed to evaluate the effects of major autohemotherapy (MAH) on pain, quality of life, functional status, and sleep quality in patients with FMS.MethodsA total of 72 patients who underwent 10 sessions of MAH between April 1, 2023 and September 1, 2023 were included in this retrospective study. A total of 10 sessions of major ozone therapy were applied to the patients, two sessions per week. In the first session, a total of 1,000 mcg of MAH (100 ml at 10 mcg/ml) was administered. In the following sessions, the concentration was gradually increased by 5 mg/ml at each session reaching up to 30 mcg/ml with a maximum cumulative dose of 3,000 mcg. Pre-and post-treatment pain status of the patients was evaluated with the Visual Analog Scale (VAS), functional status with the Fibromyalgia Impact Questionnaire (FIQ), quality of life with the Short Form-36 (SF-36), and sleep status with the Pittsburgh Sleep Quality Index (PSQI).ResultsThe mean age of 68 female and 4 male patients included in the study was determined as 54.17 ± 11.17. VAS was determined as 7.76 ± 2.01 before treatment and 4.77 ± 2.20 after treatment. FIQ score was determined as 69.08 ± 16.01 before treatment and 56.18 ± 22.46 after treatment, Pittsburg Sleep Quality Index score was determine as 10.27 ± 3.37 before treatment and 9.61 ± 2.81 after treatment. Statistically significant differences were found in VAS, FIQ, SF-36, and PSQI values before and after treatment (p < 0.001).ConclusionAccording to the study results, MAH has been found to provide significantly positive effects in reducing pain intensity, improving functional status, enhancing quality of life, and improving sleep patterns in individuals diagnosed with fibromyalgia syndrome. Considering the low side effect profile and positive clinical results of MAH in fibromyalgia patients resistant to other treatment methods, it is recommended that this method be considered as a complementary or alternative treatment option. creator: Oktay Faysal Tertemiz creator: Erkan Ozduran creator: Sinan Gursoy creator: Volkan Hanci creator: Kenan Kaygusuz creator: Ilhan Celil Ozbek creator: Mustafa Kurçaloğlu creator: Ülkü Sabuncu uri: https://doi.org/10.7717/peerj.20475 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2025 Tertemiz et al. title: Development of a predictive model for severe hyperlipidemic acute pancreatitis based on LASSO regression: a retrospective study link: https://peerj.com/articles/20471 last-modified: 2025-12-05 description: BackgroundIn recent years, the incidence of hyperlipidemic acute pancreatitis (HLAP) has been increasing. Identifying the risk factors associated with severe HLAP and developing a predictive model are crucial for early detection and intervention, thereby alleviating the disease burden. This study aimed to investigate the risk factors associated with severe HLAP and develop a predictive model.MethodsData on HLAP treated in Taixing People’s Hospital Affiliated to Yangzhou University from January 1, 2020, to June 30, 2023, were retrospectively collected and divided into a mild group (N = 296) and a moderate severe/severe group (N = 60). Univariate analysis and Least Absolute Shrinkage and Selection Operator (LASSO) regression were used to select variables, and the selected variables were incorporated into logistic regression to analyze the risk factors of severe disease. A logistic regression model was constructed. The receiver operating characteristic (ROC) curve and the area under the curve (AUC) were used to evaluate model differentiation, and the Hosmer–Lemeshow goodness-of-fit test and calibration curve were used to evaluate model consistency.ResultsThe univariate analysis showed statistically significant differences in 50 variables between the mild and moderately severe/severe groups. LASSO regression identified the following variables: D-dimer, blood calcium, cholesterol, standard bicarbonate (SB), total carbon dioxide, and C-reactive protein–albumin ratio (CAR). The constructed logistic regression model included D-dimer, blood calcium, and cholesterol, with an AUC of 0.8341 (95% CI [0.7724–0.8958]). The model’s calibration was assessed using the Hosmer–Lemeshow goodness-of-fit test (χ2 = 6.8383, P = 0.5542), and the calibration curve demonstrated that the model’s predictions closely aligned with observed outcomes.ConclusionThe risk factors of severe HLAP include D-dimer elevation, calcium depletion and cholesterol elevation. The predictive model established by logistic regression has good performance, which is helpful for early identification and intervention by clinicians. creator: Qingyu Zhang creator: Runping Han creator: Zhenxing Li creator: Kunfeng Yan creator: Xiaorong Dai creator: Gongchao Yu uri: https://doi.org/10.7717/peerj.20471 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Zhang et al. title: Are we throwing away good data? Evaluation of chimera detection algorithms on long-read amplicons reveals high false-positive rates across algorithms link: https://peerj.com/articles/20456 last-modified: 2025-12-05 description: Long-read amplicon sequencing has enabled us to return to full-length DNA barcodes, which benefit from the higher taxonomic resolution in metabarcoding-based biodiversity studies. However, chimeric sequences (artificial constructs formed when incomplete amplicons fuse during polymerase chain reaction (PCR)) remain challenging, potentially skewing diversity estimates and ecological inferences. Here, we benchmark three de novo chimera detection algorithms, uchime_denovo, removeBimeraDenovo, and chimeras_denovo, on simulated and empirical eukaryotic full-ITS (rRNA ITS1-5.8S-ITS2) datasets to evaluate their precision, sensitivity, and effects on the final OTUs composition/community structure. Upon simulated data, uchime_denovo achieved the highest precision even with default settings, whereas other algorithms displayed high false-positive chimera rates without setting adjustments. Similarly, the tests upon empirical data showed that uchime_denovo had lower false positive rates, whereas about half of the sequences in the putative chimeric batch were false positives when using chimeras_denovo and removeBimeraDenovo. We found that most of the false-negative chimeras contained multiple 5.8S regions, indicating PacBio library preparation artifacts rather than PCR artifacts. However, OTU-level comparisons indicated that overall richness and community-ordination patterns remain largely consistent across different chimera-filtering approaches with or without accounting for false positives and negatives. creator: Ali Hakimzadeh creator: Vladimir Mikryukov creator: Martin Metsoja creator: Leho Tedersoo creator: Sten Anslan uri: https://doi.org/10.7717/peerj.20456 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2025 Hakimzadeh et al.