Search Results (12)

In Pteropus spp., metabolic bone disease has been consistently associated with fruit-based diets that are deficient in calcium, vitamin D precursors, and protein, as well as limited ultraviolet B (UVB) exposure, as reported in zoological surveys and clinical observations. Comparative mammalian physiology suggests that dysregulation of the endocrine axis involving parathyroid hormone (PTH), fibroblast growth factor 23 (FGF23), calcitonin, and calcitriol may contribute to disease development, although direct species-specific endocrine data in flying foxes remain scarce. This narrative review synthesizes current knowledge from published zoological reports, clinical observations, and comparative mammalian physiology regarding the etiology, pathophysiology, and clinical expression of metabolic bone disease in captive flying foxes. Much of the available evidence is derived from juvenile Pteropus vampyrus, and its applicability to other Pteropus species remains to be fully established. The limited availability and consistency of existing data, together with the scarcity of controlled experimental and longitudinal studies, necessarily constrain the conclusions that can be drawn. Nevertheless, this review highlights key nutritional and environmental risk factors and summarizes evidence-informed preventive management strategies to improve skeletal health and welfare in managed Pteropus populations. Full article

Background/Objectives: Juvenile hallux valgus (JHV) and flexible flatfoot (FFF) often coexist in children, yet their combined surgical management remains poorly explored. This study evaluates clinical and radiographic outcomes following a simultaneous approach using lateral hemiepiphysiodesis of the first metatarsal (LHFM) and calcaneal-stop (C-Stop) procedures in skeletally immature patients. Methods: A retrospective cohort of 24 bilateral patients (48 feet) aged 10–12 underwent LHFM and C-Stop between 2017 and 2023. Radiographic evaluation included Hallux Valgus Angle (HVA), Intermetatarsal Angle (IMA), Meary’s angle (MA), and transverse TaloCalcaneal (Kite’s) Angle (tTCA). The Foot and Ankle Disability Index (FADI) and the Tegner Activity Scale (TAS) were administered at the most recent follow-up and complications were recorded. Results: The mean follow-up was 3.7 years. Postoperative radiographs showed significant improvements in all parameters, with correction inversely correlated to baseline deformity severity. Full normalization of flatfoot parameters was achieved in 68.8% of feet, with mild residual deformity in the remainder. Males showed greater radiographic correction than females. IMA and HVA improved in most cases, reaching full normalization in 53.1% and 50% of feet, respectively. Clinically, all patients showed corrected hindfoot alignment and medial arch restoration; 90% achieved the maximum FADI score and 88% resumed recreational sports. Two cases of screw migration occurred, with one revision; no further complications were reported. Conclusions: Simultaneous correction of FFF and JHV using C-Stop and LHFM proved effective, yielding significant radiographic improvements and excellent functional outcomes in most cases, with minimal complications. However, full hallux alignment was achieved in only half of the cases, suggesting that additional distal metatarsal procedures may be needed for more severe deformities. Full article

Cortisol, the main glucocorticoid in teleost, plays a central role in mediating the physiological response to stress by regulating metabolism, immune function, and growth. While its transcriptional effects are well known, its role in modulating chromatin accessibility in fish skeletal muscle remains poorly understood. In this study, we investigated the epigenomic and transcriptomic changes induced by cortisol in a juvenile rainbow trout’s (Oncorhynchus mykiss) skeletal muscle using ATAC-seq and RNA-seq. Fish were treated with a single intraperitoneal dose of cortisol (10 mg/kg) or vehicle, and muscle samples were collected 3 h post-treatment. ATAC-seq analysis revealed a total of 163,802 differentially accessible regions (DARs), with an important enrichment of open regions near transcription start sites and promoters. A total of 1612 and 1746 differentially accessible genes (DAGs) were identified in the cortisol and control groups, respectively. Motif enrichment analysis identified 89 transcription factors to be significantly enriched, among which key stress-responsive regulators such as Fos, AP-1, FoxO1/3, Mef2a/b/c, Klf5/10, and ATF4 were prominently represented. RNA-seq analysis identified 4050 differentially expressed genes (DEGs), with 2204 upregulated genes involved in autophagy, mitophagy, and FoxO signaling, while 1864 downregulated genes were enriched in spliceosome and chromatin remodeling pathways. Integrative analysis revealed 174 overlapping genes between ATAC-seq and RNA-seq datasets, highlighting pathways linked to autophagy and ATP-dependent chromatin remodeling. Four selected DEGs (sesn1, sesn2, cullin3, samtor) were validated by qPCR, showing high concordance with transcriptomic data. These findings provide new insights into cortisol-mediated regulation of chromatin dynamics and gene expression in teleost skeletal muscle and underscore the importance of epigenetic mechanisms in fish stress responses. Full article

Fish red blood cells (RBCs) are nucleated, transcriptionally active, and key players in both gas transport and immune responses. They are the primary targets of Orthoreovirus piscis (PRV), the etiological agent of heart and skeletal muscle inflammation (HSMI), which includes three genotypes (PRV-1, PRV-2, and PRV-3), linked to circulatory disorders in farmed salmon. In Chile, PRV-3 affects the coho salmon (Oncorhynchus kisutch), but host–pathogen interactions remain poorly characterized. This study compared the interactions of PRV-3 in coho salmon and PRV-1 in Atlantic salmon (Salmo salar) using RBC infection models. RBCs were isolated from healthy juvenile salmon (n = 3) inoculated with either PRV-1 (Ct = 18.87) or PRV-3 (Ct = 21.86). Poly I:C (50 µg/mL) was used as a positive control for the antiviral response. Cells were monitored for up to 14 days post-infection (dpi). PRV-3 infection in coho salmon RBCs caused significant metabolic disruption, apoptosis from 7 dpi, and correlated with increasing viral loads. In contrast, PRV-1 infection in Atlantic salmon RBCs showed limited apoptosis and maintained cell viability. Coho salmon RBCs upregulated rig-i, mx, and pkr transcripts, indicating activation of the type I interferon pathway, whereas Atlantic salmon RBCs exhibited a more attenuated response. PRV-3 induced notable morphological changes in coho salmon RBCs, although neither PRV-3 nor PRV-1 caused hemolysis. These findings highlight species-specific differences in RBC responses to PRV infection and provide new insights into the pathogenesis of PRV-3 and PRV-1. Full article

Twist2 plays a pivotal regulatory role in the growth of skeletal muscle across various organisms. Nonetheless, the specific mechanism by which Twist2 governs skeletal muscle function in fish, particularly in the economically significant Chinese perch (Siniperca chuatsi), remains unclear. Within the muscle injury model in Chinese perch, we observed that Twist2 expression was upregulated during the repair phase of fast muscle tissue, exhibiting an expression pattern analogous to that of Pax7. Following the knockdown of Twist2 using Twist2-specific in vivo-siRNA in fast muscle tissues, the expression of myogenic regulatory factors (MRFs) and Myomaker was significantly reduced in the Twist2-siRNA-treated group compared with the control group, whereas no significant differences were observed for Pax3 and Pax7. Furthermore, the diameter of myofibers and the number of nuclei in single myofibers were reduced, and concurrently, the number of BrdU-positive cells (proliferating cells) was significantly reduced in the Twist2-siRNA-treated group. Taken together, this study demonstrates that Twist2 promotes myoblast proliferation and fusion, thereby regulating fast muscle growth in juvenile Chinese perch. These findings provide a clear direction for further exploration of molecular mechanisms underlying skeletal muscle growth in economic fish species. Full article

Evidence of trophic interactions between sharks and cetaceans is rather widespread in the fossil record, consisting as it does of tooth marks on bones and rarer teeth or tooth fragments embedded in (or associated with) skeletal remains. Here, we reappraise a partial mysticete (baleen whale) forelimb that was collected more than a century ago from Pliocene deposits exposed at the celebrated fossil locality of Orciano Pisano (Tuscany, central Italy). This specimen, which is revealed to originate from an early juvenile individual, features shark tooth marks on both the humerus and radius. Whether these traces are due to active predation or to scavenging cannot be ascertained. During the Pliocene, the Mediterranean Basin was inhabited by a diverse elasmobranch fauna, including a number of mammal-eating forms that no longer inhabit the Mediterranean Sea (e.g., Galeocerdo and some Carcharhinus spp. as well as the extinct Parotodus). Early juvenile mysticetes were also likely more common than today in the Pliocene Mediterranean Sea, which may have contained balaenid and balaenopterid calving grounds, thus providing the Mediterranean mammal-eating sharks with vulnerable, energetically valuable potential prey items. Thus, our results evoke a kind of trophic interaction that was likely common and ecologically relevant in the Pliocene Mediterranean Sea. Full article

The 2978 faunal bone remains recovered from the Bronze Age levels at the Castillejo del Bonete site between 2005 and 2019 were analyzed in this study. In the main structure (Great Tumulus 1, Tumulus 2, and Tomb 5), the faunal bone remains were identified and interpreted as offerings in a funerary context. In Enclosure 4, a large building possibly dedicated to the celebration of wakes and rituals—including the eating of food and drinking—in honor of the deceased, the anthropic modifications on the bone surfaces indicate their possible consumption. The cave is constituted by four galleries with inhumations (in Galleries 2, 3, and 4) and pithoi (in Gallery 4). Wild and domestic animals were identified in the cavity, and the caprine (likely sheep) is the best represented taxa in the entire cave. The almost complete skeletal representation; the predominance of fetal, neonate, and juvenile individuals; the absence of anthropic modifications related to consumption, in addition to the bone industry made of caprine bones (such as an eye idol and anthropomorphic artefacts), suggest that caprines were used as offerings to the deceased that accompany them. Postdepositional taphonomic alterations, the animals not having been found in anatomical connection, and the refits of the bones between different stratigraphical units indicate the repeated use of the cave during the Bronze Age. Full article

Juvenile idiopathic inflammatory myopathy (JIIM) is a rare systemic autoimmune disease characterized by skeletal muscle weakness with or without a skin rash. Juvenile dermatomyositis (JDM) is the most common subtype of JIIM, accounting for 80% of JIIM. Recent studies identified several myositis-specific autoantibodies (MSAs) and myositis-associated autoantibodies (MAAs). Each MSA or MAA is associated with distinct clinical features and outcomes, although there are several differences in the prevalence of MSA/MAA and autoantibody–phenotype relationships between age and ethnic groups. Histopathological studies have revealed critical roles of type I interferons and vasculopathy in the development of JDM. Serological classification mostly corresponds to clinicopathological classification. Novel therapeutic agents, such as biologics and Janus kinase inhibitors (JAKi), have been developed; however, to date, there is a lack of high-level evidence. As advances in treatment have reduced the mortality rate of JIIM, recent studies have focused on medium- and long-term outcomes. However, rapidly progressive interstitial lung disease (RP-ILD) remains a major cause of death in anti-melanoma differentiation gene 5 autoantibody-positive JDM. Early diagnosis and intervention using a multi-drug regimen is critical for the treatment of RP-ILD. Rituximab and JAKi may reduce mortality in patients with JDM-associated RP-ILD refractory to conventional therapy. Full article

Age-at-death is one of the most valuable pieces of information in a biological profile, and is an important step in identifying remains. Age-at-death estimation by dental means is performed by forensic odontologists and forensic anthropologists in their daily casework tasks. Both forensic odontologists and forensic anthropologists must be aware of all of the age indicators and of all of the methods that can offer the sufficient scientific robusticity that forensic cases require. Osteological and dental methods of age estimation rely on developmental changes in younger individuals and on degenerative changes in older individuals. Skeletal methods based on developmental changes are highly reliable, while methods based on degenerative or post-formation changes show higher variability. From all skeletal methods, those relying on tooth formation and development are the most accurate to assess an individual’s age. Dental methods of age estimation can be implemented in the skeletal analysis of juvenile and adult remains, representing an additional indicator of age. The aim of this review paper is to provide a practical reference for applying dental age estimation to human remains as a part of skeletal analysis. Full article

It is well understood that intrinsic factors of bone contribute to bone diagenesis, including bone porosity, crystallinity, and the ratio of organic to mineral components. However, histological analyses have largely been limited to adult bones, although with some exceptions. Considering that many of these properties are different between juvenile and adult bone, the purpose of this study is to investigate if these differences may result in increased degradation observed histologically in fetal and juvenile bone. Thirty-two fetal (n = 16) and juvenile (n = 16) Sus scrofa domesticus femora subject to different depositions over a period of two years were sectioned for histological observation. Degradation was scored using an adapted tunneling index. Results showed degradation related to microbial activity in both fetal and juvenile remains across depositions as early as three months. Buried juvenile remains consistently showed the greatest degradation over time, while the blanket fetal remains showed more minimal degradation. This is likely related to the buried remains’ greater contact with surrounding soil and groundwater during deposition. Further, most of the degradation was seen in the subendosteal region, followed by the subperiosteal region, which may suggest the initial microbial attack is from endogenous sources. Full article

Ciliopathies are genetic syndromes that link skeletal dysplasias to the dysfunction of primary cilia. Primary cilia are sensory organelles synthesized by intraflagellar transport (IFT)—A and B complexes, which traffic protein cargo along a microtubular core. We have reported that the deletion of the IFT-A gene, Thm2, together with a null allele of its paralog, Thm1, causes a small skeleton with a small mandible or micrognathia in juvenile mice. Using micro-computed tomography, here we quantify the craniofacial defects of Thm2^−/−; Thm1^aln/+ triple allele mutant mice. At postnatal day 14, triple allele mutant mice exhibited micrognathia, midface hypoplasia, and a decreased facial angle due to shortened upper jaw length, premaxilla, and nasal bones, reflecting altered development of facial anterior-posterior elements. Mutant mice also showed increased palatal width, while other aspects of the facial transverse, as well as vertical dimensions, remained intact. As such, other ciliopathy-related craniofacial defects, such as cleft lip and/or palate, hypo-/hypertelorism, broad nasal bridge, craniosynostosis, and facial asymmetry, were not observed. Calvarial-derived osteoblasts of triple allele mutant mice showed reduced bone formation in vitro that was ameliorated by Hedgehog agonist, SAG. Together, these data indicate that Thm2 and Thm1 genetically interact to regulate bone formation and sculpting of the postnatal face. The triple allele mutant mice present a novel model to study craniofacial bone development. Full article

Progressive biomineralization of a skeleton occurs during ontogeny in most animals. In fishes, larvae are poorly mineralized, whereas juveniles and adults display a progressively more biomineralized skeleton. Fossil remains primarily consist of adult specimens because the fossilization of poorly-mineralized larvae and juveniles necessitates exceptional conditions. The Miguasha Fossil-Lagerstätte is renowned for its Late Devonian vertebrate fauna, revealing the exceptional preservation of fossilized ontogenies for 14 of the 20 fish species from this locality. The mineralization of anatomical structures of the acanthodian Triazeugacanthus affinis from Miguasha are compared among larval, juvenile and adult specimens using Energy Dispersive X-ray Spectrometry. Chemical composition of anatomical structures of Triazeugacanthus reveals differences between cartilage and bone. Although the histology and anatomy is well-preserved, Fourier transform infrared spectrometry shows that the original chemical composition of bone is altered by diagenesis; the mineral phase of the bone (i.e., hydroxyapatite) is modified chemically to form more stable carbonate-fluorapatite. Fluorination occurring in mineralized skeletal structures of adult Triazeugacanthus is indicative of exchanges between groundwater and skeleton at burial, whereas the preservation of larval soft tissues is likely owing to a rapid burial under anoxic conditions. The exceptional state of preservation of a fossilized ontogeny allowed us to characterize chemically the progressive mineralization of the skeleton in a Devonian early vertebrate. Full article