PeerJ最新文献

Pisinnocaris subconigera was first described as a rare, small euarthropod from the early Cambrian Chengjiang biota, southwestern China. The taxonomic validity of this species was later challenged due to the lack of essential morphological details to differentiate it from Fuxianhuia protensa, especially from the juvenile perspective. Here, we examined the holotype and additional specimens of P. subconigera with multiple imaging techniques, such as microscope optical imaging, micro-CT scanning and computer-based 3D rendering, and revealed the previously unknown ventral organization of P. subconigera. New findings include four short prothoracic segments each bearing a pair of biramous appendages, four opisthothoracic segments each with four pairs of appendages, and four limbless abdominal segments. Both the small and large individuals exhibit unique and consistent morphological characteristics, indicating that P. subconigera does not represent the larval or juvenile form of any fuxianhuiid as previously proposed. Combined with phylogenetic analyses, our study suggests that P. subconigera remians as a valid member of the early Cambrian fuxianhuiids.

Schistocephalus solidus, a parasitic cestode with a multi-host life cycle, reproduces in its terminal host either by outcrossing with similarly sized individuals or selfing. Previous work found that selfing greatly depresses egg hatching rates, presumably as a result of inbreeding depression. We designed an experiment to test whether S. solidus evolved quorum sensing (QS) during hatching as a mechanism to facilitate synchronized infection, thereby increasing the opportunity for outcrossing in its terminal host. We also performed exploratory analyses to test whether QS varies across parasite populations and cross type (i.e., whether progeny were produced via outcrossing or selfing), though these had limited statistical power due to low sample sizes across treatments. We predicted that if QS was present, it would be common across all populations and that higher egg density within a small area would result in higher hatching rates. We also expected that outcrossed eggs would hatch at higher rates than those produced via selfing. While we found different hatching rates between populations, there was no evidence for QS. We also observed that selfed eggs hatched at lower rates than outcrossed eggs, replicating previous findings. Although we failed to find density dependent hatching within the scope of our sample size, we discuss the conditions that may either favor or disfavor QS evolution across S. solidus and other helminth populations.

Background: Physiological traits, such as the critical thermal maximum (CT_max, defined as an individual's upper thermal tolerance limit), can be important for understanding species' vulnerability to climate and habitat change. A separate trait, thermal acclimation capacity, is defined as the physiological adjustment of organisms to temperature variation, which can influence phenotypic traits such as CT_max. The relationship between acclimation capacity and CT_max has been widely studied in ectotherms like fish, amphibians, and reptiles, and it is generally observed that CT_max increases with higher acclimation temperatures. However, there is a lack of information about whether amphibians respond differently to long- versus short-term acclimation. Understanding thermal acclimation capacity under rapid environmental change is important, as high acclimation capacity may reduce vulnerability. Here, we evaluated the thermal acclimation capacity of the Eastern Red-backed Salamander, Plethodon cinereus, in response to short- and long-term acclimation treatments in a laboratory setting.

Methods: We exposed salamanders to three different treatments: control animals were maintained at 15 °C for 30 days; animals in the short-term acclimation group were maintained at 15 °C for 28 days, and 23 °C for 48 hours before testing CT_max; and animals in the long-term acclimation group were maintained at 23 °C for 30 days. We measured the CT_max of all animals at the end of the experiment to determine whether tolerance to high temperatures varied depending on the length of exposure to warm conditions.

Results: Although we observed a slight increase in CT_max from the control treatment to the short-term (+0.93 °C) and long-term (+0.98 °C) acclimation treatments, the difference in CT_max between acclimation treatments was small (0.05 °C), and none of the differences were statistically significant.

Discussion: Several factors may explain the low variation in CT_max described in our study, including phylogenetic conservation of upper thermal limits, or a lack of sufficient temperature differences in our treatments to elicit a physiological response. Regardless, our results provide limited evidence that different acclimation periods affect the degree of phenotypic plasticity in CT_max in Plethodon cinereus.

Background: The geographical region and organ-specific accumulation of metabolites in medicinal plants are critical determinants of their pharmaceutical efficacy. Rehmannia chingii, an endemic species native to eastern China and a significant member of the genus Rehmannia, exhibits multiple bioactive properties in both its leaves and roots. However, spatial distribution of its pharmaceutical ingredients across various geographical regions remains inadequately understood.

Methods and results: This study combined widely targeted metabolomics with the Traditional Chinese Medicine System Drug Analysis Platform (TCMSP) to investigate the accumulation patterns of medicinal ingredients in the leaves and roots of fresh R. chingii from two distinct geographical regions. Among the 1,420 metabolites identified, four differential biomarkers were identified: p-coumaroylcadaverine and protocatechuic acid-4-o-glucoside, which were primarily associated with geographical differentiation, and 5, 6-dimethyl-2-benzofuran-1, 3-dione and daphnin, which were indicative of organ type classification. Additionally, 31 potential bioactive ingredients were prioritized via TCMSP screening. Metabolic profiling further revealed that multiple flavonoids were enriched in leaves, whereas roots accumulated higher levels of tangeretin, 6-o-p-coumaroylajugol, guanosine, virexilactone, and aucubin. Notably, coniferin and tangeretin, with oral bioavailability values ≥30% and drug-likeness values ≥0.18, were identified as key potential bioactive marker ingredients, and they were highly abundant in R. chingii from the Tianmu Mountain region of Hangzhou.

Conclusion: These findings highlight the critical role of geographic and organ-specific factors in determining the metabolic profiles of R. chingii, thereby advancing our understanding of its medicinal value and providing a theoretical basis for the rational exploitation and utilization of its medicinal resources.

Background: Nails in the elderly undergo several structural changes related to aging with respect to surface, thickness, color, and growth pattern. The present study explores the potential association between nail alterations and zinc levels in this population.

Methods: A total of 64 subjects aged ≥60 years with or without nail changes were recruited from the Dermatology and Venereology Outpatient Clinic at Dr. Cipto Mangunkusumo Hospital, Jakarta, Indonesia. Their nail features were observed clinically and evaluated utilizing dermoscopy, and nail clippings weighing a total of 200 milligrams were collected from each subject for nail zinc concentration measurement. Appropriate statistical tests were employed to determine the relationship between nail zinc levels and the structural alterations, as well as the patients' comorbidities and medications, at a significance level of 0.05.

Results: Most subjects in our study showed altered nail profiles in multiple digits (75.0%) with a predilection for toenails (62.3%), and the first toenail was primarily affected. The commonest dermoscopic features displayed in altered nails include nail plate pigmentation (n = 64), distal edge thickening (n = 39), and surface changes (n = 34). The average nail zinc concentration was lower in the elderly with nail changes than in those without, albeit with no statistically significant differences (p = 0.687). Subgroup analyses according to comorbidities (hypertension, diabetes mellitus type 2, and dyslipidemia) and medications (antihypertensives, antidiabetics, antidyslipidemic drugs, and anticonvulsants) also exhibited no discrepancies.

Conclusions: This study highlights the complex interactions among nail structural changes, zinc levels, comorbidities, and medications; hence, further research is warranted to obtain a deeper understanding.

When RayStation is used for Halcyon treatment planning and the plan is transferred to the ARIA/Eclipse system for delivery verification, the dose must be recalculated using the Anisotropic Analytical Algorithm (AAA) or AcurosXB algorithm for compatibility. This study evaluated the dosimetric differences among the Collapsed Cone (CC), AAA, and AcurosXB algorithms for non-small cell lung cancer (NSCLC) volumetric modulated arc therapy (VMAT) plans on the Halcyon platform. Treatment plans for 60 lung cancer patients were initially generated using the CC algorithm in RayStation and then recalculated in Eclipse using AAA and AcurosXB without re-optimization or renormalization. Systematic variations were observed among the three algorithms. AcurosXB showed the largest reductions in target doses compared with CC (up to a 1.56% reduction in clinical target volume (CTV) D2%), while AAA demonstrated smaller differences. For planning target volume (PTV) metrics, both AAA and AcurosXB yielded lower doses than CC (AAA up to 2.16% in D95%; AcurosXB up to 1.58% in D2%). All variations in CTV and PTV metrics remained within approximately 1.7%. For organ-at-risk doses, AAA produced slightly lower values than CC, whereas AcurosXB yielded consistently lower doses across most parameters. Overall, this study shows that AAA and AcurosXB provide slightly lower dose estimates than CC for the same Halcyon plan, especially for PTV and organ-at-risk metrics. These results highlight the importance of consistent dose-calculation methodology in NSCLC radiotherapy, particularly in cross-platform workflows between RayStation and Eclipse.

Background: Endometriosis (EM) is a disease related to reproductive dysfunction. The mechanism of epigenetic factors (EF) in EM still needs to be studied. Emerging evidence suggests that EF plays a role in the development of EM. However, the specific molecular pathways through which they exert their effects remain incompletely understood, necessitating further in-depth research. This study aimed to explore the mechanisms underlying EF in EM.

Methods: In the study, the differentially expressed genes (DEGs) between EM and control were obtained by analyzing transcriptome data from public databases. Candidate genes were obtained by taking the intersection of DEGs and EF-related genes (EF-RGs), which were further screened using machine learning algorithms, receiver operating characteristic analysis, and expression levels in the EM and control samples to obtain biomarkers. The potential mechanisms of biomarkers in EF were further analyzed by constructing a nomogram model, gene set enrichment analysis (GSEA), immune infiltration analysis, expression profiling in tissues and cells, molecular regulatory networks, and drug prediction. The expression of these biomarkers was validated using in vitro experiments.

Results: Histone deacetylase 9 (HDAC9), YY1-associated factor 2 (YAF2), and cell division cycle 6 (CDC6) were identified as EF-associated biomarkers in EM. These biomarkers had excellent diagnostic ability for EM. HDAC9, CDC6, and YAF2 were respectively significantly enriched in focal adhesion and oxidative phosphorylation pathways. Four types of differentially distributed immune cells were identified between EM and control samples using immune infiltration analysis. The expression of these biomarkers in different tissues varied with age and menstrual cycle. The expression levels of biomarkers were higher in endothelial cells. Ten miRNAs and 24 lncRNAs that targeted these biomarkers were screened, and there were 12 transcription factors (TFs) in which all the biomarkers acted together. All biomarkers worked together for drugs, including bisphenol A, benzo(a)pyrene, and cisplatin. The results of in vitro experiments were consistent with those of the bioinformatics analysis.

Conclusion: This study identified three biomarkers (HDAC9, CDC6, and YAF2) and the potential therapeutic drugs for EM. These results provide new insights into the mechanisms underlying EM development.

Background: Adult scoliosis, which is characterized by a persistent lateral deviation of the spine of at least 10° in the frontal plane along with vertebral rotation in adulthood, can result from various causes, including degenerative changes, untreated childhood scoliosis, spinal trauma, and prior surgeries. Traditionally, spinal curvature is assessed by measuring the Cobb angle via radiographic imaging; however, concerns over radiation exposure have prompted exploration of alternative diagnostic tools.This study aims to evaluate the effectiveness of a newly developed three-dimensional (3D) body scanner, equipped with 12 depth cameras, in assessing spinal alignment and measuring the Cobb angle in patients with adult scoliosis, in comparison with radiographic imaging.

Methods: In this prospective cohort study, 40 patients with adult scoliosis-both idiopathic and degenerative-underwent evaluation using both radiographic imaging and 3D body scanning. Cobb angles were measured by both methods. Pearson and Spearman's rank correlation coefficients were calculated to assess the linear and monotonic relationships between measurements. Measurement accuracy was quantified using the mean bias from Bland-Altman analysis and spatial agreement of spinal positions was further evaluated using the Intersection over Union (IoU) metric. Univariable and multivariable regression analyses were performed to assess whether body habitus (body mass index, waist circumference, waist-to-height ratio, age, and sex) influenced the absolute error between 3D body scanner-predicted and radiographic Cobb angles.

Results: Cobb angle measurements obtained from 3D body scanning were highly correlated with those from radiography (Pearson r = 0.92, P < 0.001; Spearman ρ = 0.85, P < 0.001), indicating strong linear and monotonic agreement. Bland-Altman analysis showed a small mean bias of -1.06 (95% limits of agreement: -10.25 to 8.12). The average IoU was 0.89, indicating substantial spatial agreement in spinal position predictions. Importantly, obesity indices (body mass index, waist circumference, waist-to-height ratio) were not significantly associated with the absolute error between 3D body scanner-predicted and radiographic Cobb angles in either univariable or multivariable analyses.

Conclusions: The 3D body scanner exhibits promise for assessing spinal alignment and measuring the Cobb angle in patients with adult scoliosis, offering a reliable alternative to traditional radiographic methods. Its accuracy was not affected by obesity-related indices, supporting its applicability across diverse patient body types. Future research should focus on refining scanning protocols and integrating patient-reported outcomes to enhance clinical utility.

Glacial cycles operating across Beringia have repeatedly exposed large swathes of the Bering Land Bridge, intermittently isolating and reuniting North American and Eurasian taxa. In high-latitude birds, these cycles are hypothesized to have been important in driving divergence and speciation. These repeated events have resulted in multiple trans-Beringian avian sister populations of varying degrees of taxonomic depth distributed across modern Beringia. We asked how these cyclic pulses have affected the temporal distribution and number of overall divergence events across Beringia. We sequenced full mitogenomes at high depth from 39 lineage pairs of varying levels of divergence, totaling 432 individuals of seven orders, 14 families, and 49 species from both Eurasia and North America. We then used a hierarchical approximate Bayesian comparative (hABC) approach to estimate the number and distribution of divergence events between the population pairs, using subsampled datasets. Net nucleotide divergence (D_A ) and Jukes-Cantor distance (JC-distance) were also calculated for each pairwise comparison to estimate divergence dates between taxa, using calibrated rates appropriate for shallow avian divergence events. Average divergence times were 200,000 ya for population-level taxa (n = 16), 720,000 ya for subspecies (n = 12), and 1 Mya for species (n = 11), although we consider these dating estimates conservative because of a lack of appropriate calibration for data of this quality. We found eighteen taxon pairs to be significantly differentiated (p < 0.05) by F_ST or substantially differentiated by haplotype clade, bounding the number of potential overall divergence events from 1 to 18, and two subsets of the full mitogenomic dataset analyzed in MTML-msBayes strongly supported simultaneous divergence of all Beringian lineages. However, this finding of simultaneous divergence is biologically unusual given the substantial variation in divergence dates among taxa and might indicate a relatively continuous spread of vicariance events, which is difficult to distinguish from a single, simultaneous vicariance event.