Contraceptive effect of a gonadotropin-releasing hormone vaccine on captive male brown bears (Ursus arctos).

Fertility control has traditionally been applied in zoos to control captive populations, and reversible contraception is important. However, contraceptive methods for male bears have not been reported. We aimed to establish a reversible contraceptive for male brown bears by investigating the effects of a gonadotropin-releasing hormone (GnRH) vaccine (Improvac®) that was developed for the immune castration of pigs. We vaccinated six bears with two sequential doses of 400 (n = 2) or 600 µg Improvac® (n = 4) with a 1-month interval during the pre-breeding season (February to April). We compared the reproductive parameters (testosterone levels and semen parameters) of the six vaccinated and four non-vaccinated (control) bears once during the breeding season (May or June). To investigate whether the reproductive performance could be restored in the following year of contraception, we also compared the reproductive parameters once during the breeding season in two bears between the year with GnRH vaccination and the following year without vaccination. Vaccination treatments suppressed reproductive parameters in 5 bears, although vaccination with 400 µg of Improvac® was not effective in one bear. Testosterone levels and the rate of progressive sperm motility were significantly lower, and total sperm count and testis size tended to be lower in vaccinated bears, compared with the controls. Blood biochemical findings and direct observations after Improvac® vaccination did not reveal side effects. Moreover, testosterone levels and spermatogenic scores of two bears were restored in the following year. We confirmed that the Improvac® vaccine elicited a reversible contraceptive effect in male brown bears.

Oral microbiome sequencing revealed the enrichment of Fusobacterium sp., Porphyromonas sp., Campylobacter sp., and Neisseria sp. on the oral malignant fibroma surface of giant panda.

Introduction: Microbial community composition is closely associated with host disease onset and progression, underscoring the importance of understanding host-microbiota dynamics in various health contexts. Methods: In this study, we utilized full-length 16S rRNA gene sequencing to conduct species-level identification of the microorganisms in the oral cavity of a giant panda (Ailuropoda melanoleuca) with oral malignant fibroma. Results: We observed a significant difference between the microbial community of the tumor side and non-tumor side of the oral cavity of the giant panda, with the latter exhibiting higher microbial diversity. The tumor side was dominated by specific microorganisms, such as Fusobacterium simiae, Porphyromonas sp. feline oral taxon 110, Campylobacter sp. feline oral taxon 100, and Neisseria sp. feline oral taxon 078, that have been reported to be associated with tumorigenic processes and periodontal diseases in other organisms. According to the linear discriminant analysis effect size analysis, more than 9 distinct biomarkers were obtained between the tumor side and non-tumor side samples. Furthermore, the Kyoto Encyclopedia of Genes and Genomes analysis revealed that the oral microbiota of the giant panda was significantly associated with genetic information processing and metabolism, particularly cofactor and vitamin, amino acid, and carbohydrate metabolism. Furthermore, a significant bacterial invasion of epithelial cells was predicted in the tumor side. Discussion: This study provides crucial insights into the association between oral microbiota and oral tumors in giant pandas and offers potential biomarkers that may guide future health assessments and preventive strategies for captive and aging giant pandas.

Remodeling of skeletal muscle myosin metabolic states in hibernating mammals.

Hibernation is a period of metabolic suppression utilized by many small and large mammal species to survive during winter periods. As the underlying cellular and molecular mechanisms remain incompletely understood, our study aimed to determine whether skeletal muscle myosin and its metabolic efficiency undergo alterations during hibernation to optimize energy utilization. We isolated muscle fibers from small hibernators, Ictidomys tridecemlineatus and Eliomys quercinus and larger hibernators, Ursus arctos and Ursus americanus. We then conducted loaded Mant-ATP chase experiments alongside X-ray diffraction to measure resting myosin dynamics and its ATP demand. In parallel, we performed multiple proteomics analyses. Our results showed a preservation of myosin structure in U. arctos and U. americanus during hibernation, whilst in I. tridecemlineatus and E. quercinus, changes in myosin metabolic states during torpor unexpectedly led to higher levels in energy expenditure of type II, fast-twitch muscle fibers at ambient lab temperatures (20 °C). Upon repeating loaded Mant-ATP chase experiments at 8 °C (near the body temperature of torpid animals), we found that myosin ATP consumption in type II muscle fibers was reduced by 77-107% during torpor compared to active periods. Additionally, we observed Myh2 hyper-phosphorylation during torpor in I. tridecemilineatus, which was predicted to stabilize the myosin molecule. This may act as a potential molecular mechanism mitigating myosin-associated increases in skeletal muscle energy expenditure during periods of torpor in response to cold exposure. Altogether, we demonstrate that resting myosin is altered in hibernating mammals, contributing to significant changes to the ATP consumption of skeletal muscle. Additionally, we observe that it is further altered in response to cold exposure and highlight myosin as a potentially contributor to skeletal muscle non-shivering thermogenesis.

Many animals use hibernation as a tactic to survive harsh winters. During this dormant, inactive state, animals reduce or limit body processes, such as heart rate and body temperature, to minimise their energy use. To conserve energy during hibernation, animals can use different approaches. For example, garden dormice undergo periodic states of extremely low core temperatures (down to 4­8^oC); whereas Eurasian brown bears see milder temperature drops (down to 23­25^oC). An important organ that changes during hibernation is skeletal muscle. Skeletal muscle typically uses large amounts of energy, making up around 50% of body mass. To survive, hibernating animals must change how their skeletal muscle uses energy. Traditionally, active myosin ­ a protein found in muscles that helps muscles to contract ­ was thought to be responsible for most of the energy use by skeletal muscle. But, more recently, resting myosin has also been found to use energy when muscles are relaxed. Lewis et al. studied myosin and skeletal muscle energy use changes during hibernation and whether they could impact the metabolism of hibernating animals. Lewis et al. assessed myosin changes in muscle samples from squirrels, dormice and bears during hibernation and during activity. Experiments showed changes in resting myosin in squirrels and dormice (whose temperature drops to 4­8^oC during hibernation) but not in bears. Further analysis revealed that cooling samples from non-hibernating muscle to 4­8^oC increased energy use in resting myosin, thereby generating heat. However, no increase in energy use was found after cooling hibernating muscle samples to 4­8^oC. This suggest that resting myosin generates heat at cool temperatures ­ a mechanism that is switched off in hibernating animals to allow them to cool their body temperature. These findings reveal key insights into how animals conserve energy during hibernation. In addition, the results show that myosin regulates energy use in skeletal muscles, which indicates myosin may be a potential drug target in metabolic diseases, such as obesity.

PMab-314: An Anti-Giant Panda Podoplanin Monoclonal Antibody.

The giant panda (Ailuropoda melanoleuca) is one of the important species in worldwide animal conservation. Because it is essential to understand the disease of giant panda for conservation, histopathological analyses of tissues are important to understand the pathogenesis. However, monoclonal antibodies (mAbs) against giant panda-derived proteins are limited. Podoplanin (PDPN) is an essential marker of lung type I alveolar epithelial cells, kidney podocytes, and lymphatic endothelial cells. PDPN is also overexpressed in various human tumors, which are associated with poor prognosis. Here, an anti-giant panda PDPN (gpPDPN) mAb, PMab-314 (mouse IgG1, kappa) was established using the Cell-Based Immunization and Screening method. PMab-314 recognized N-terminal PA16-tagged gpPDPN-overexpressed Chinese hamster ovary-K1 cells (CHO/PA16-gpPDPN) in flow cytometry. The KD value of PMab-314 for CHO/PA16-gpPDPN was determined as 1.3 × 10-8 M. Furthermore, PMab-314 is useful for detecting gpPDPN in western blot analysis. These findings indicate that PMab-314 is a useful tool for the analyses of gpPDPN-expressed cells.

Optimization of Bear Oil Extraction Process and Hair Growth Activity.

According to ancient Chinese books, bear grease has the effects of strengthening muscles and bones, which is beneficial for weakness, but there is relatively little research on it. Thus, the extraction of it is beneficial for compensating for research in this area. In this study, a uniform experimental design method was used to optimize the extraction process of bear grease by enzymatic hydrolysis extraction, and the extraction rate can reach 81.89% under optimized extraction conditions. Furthermore, the components of bear grease obtained by this study were analyzed by GC-MS, and the results showed that ursolic oil was rich in unsaturated fatty acids (67.51%), which was higher than that of the traditional method (66.92%). The composition of bear grease extracted by the enzymatic method was also better than that extracted by the traditional method. In addition, bear grease obtained in this study had the obvious activity of promoting hair growth. The length, weight, and number of hair follicles in the depilation area of mice in the high-dose group were significantly different from those in the blank group (p < 0.01). This study optimized the extraction process of bear grease and conducted a preliminary analysis of its fatty acid composition, which is expected to provide some reference for the development of the medicinal value of bear grease.

Single-cell mRNA sequencing of giant panda (Ailuropoda melanoleuca) seminoma reveals the cellular and molecular characteristics of tumour cells.

Testicular tumours are zoonoses that can occur in not only human, but other animals, include giant pandas. A middle-aged male giant panda named Fufu was diagnosed with a testicular tumour and underwent surgery to remove the entire left testis. The testis was mainly composed of three substantive parts: normal tissue on the outside, tumour tissue in the middle, and necrosis in the centre. HE stains revealed that the tumour was a seminoma. Single-cell mRNA sequence was applied to characterise cellular states and molecular circuitries of giant panda testicular seminoma. Only germ cell markers expressed in nearly all tumour cells, and the tumour cells appeared to be the same subtype of seminoma cells. We identified four clusters with unique genes expression. They were early apoptosis cells (EAC), inactive cells (IC), active cells subcluster 1 (AC-1) and active cells subcluster 2 (AC-2). We utilised monocle tools and found that IC cells was in the initiation stage, and EAC was one type of terminal stage, suggesting that tumour cells may undergo apoptosis in the future. AC-2 was another type of terminal stage, representing a group of progressive cells. Our study represents the first report to utilise scRNA-seq to characterise the cellular states and molecular circuitries of a giant panda testicular tumour. This investigation proposes CD117 and CD30 as dependable markers for future pathologic diagnosis. Our findings also suggest that CTSV and other genes with unique expression patterns in active and progressive giant panda seminoma cells may act as early prognostic biomarkers.

Maxillary Ameloblastoma in an Asiatic Black Bear (Ursus thibetanus).

An approximately 30-year-old intact female Asiatic black bear (Ursus thibetanus) was presented for annual examination and a history of ptyalism. A large 9.5 cm × 5 cm × 5 cm, firm, round mass was identified attached to the hard palate on physical examination. A computed tomography scan was performed, and the heterogeneous, mineral-attenuating mass was seen arising from the right aspect of the palatine bone and extending rostrally to the level of the last maxillary molars, caudally into the oropharynx, and dorsally into the nasal choana. Surgical debulking was performed to remove the portion of the mass within the oral cavity. Histopathologic analysis was consistent with a keratinizing ameloblastoma. Nine months postoperatively, the patient was asymptomatic for the tumor. The patient was euthanized 23-months postoperatively, and severe diffuse pustular dermatitis, growth of the ameloblastoma on the hard palate, and various degenerative and aging changes were noted on necropsy at that time. This is the first report of an ameloblastoma in a member of the Ursidae family.

Testing foraging optimization models in brown bears: Time for a paradigm shift in nutritional ecology?

How organisms obtain energy to survive and reproduce is fundamental to ecology, yet researchers use theoretical concepts represented by simplified models to estimate diet and predict community interactions. Such simplistic models can sometimes limit our understanding of ecological principles. We used a polyphagous species with a wide distribution, the brown bear (Ursus arctos), to illustrate how disparate theoretical frameworks in ecology can affect conclusions regarding ecological communities. We used stable isotope measurements (δ13 C, δ15 N) from hairs of individually monitored bears in Sweden and Bayesian mixing models to estimate dietary proportions of ants, moose, and three berry species to compare with other brown bear populations. We also developed three hypotheses based on predominant foraging literature, and then compared predicted diets to field estimates. Our three models assumed (1) bears forage to optimize caloric efficiency (optimum foraging model), predicting bears predominately eat berries (~70% of diet) and opportunistically feed on moose (Alces alces) and ants (Formica spp. and Camponotus spp; ~15% each); (2) bears maximize meat intake (maximizing fitness model), predicting a diet of 35%-50% moose, followed by ants (~30%), and berries (~15%); (3) bears forage to optimize macronutrient balance (macronutrient model), predicting a diet of ~22% (dry weight) or 17% metabolizable energy from proteins, with the rest made up of carbohydrates and lipids (~49% and 29% dry matter or 53% and 30% metabolizable energy, respectively). Bears primarily consumed bilberries (Vaccinium myrtillus; 50%-55%), followed by lingonberries (V. vitis-idaea; 22%-30%), crowberries (Empetrum nigrum; 8%-15%), ants (5%-8%), and moose (3%-4%). Dry matter dietary protein was lower than predicted by the maximizing fitness model and the macronutrient balancing model, but protein made up a larger proportion of the metabolizable energy than predicted. While diets most closely resembled predictions from optimal foraging theory, none of the foraging hypotheses fully described the relationship between foraging and ecological niches in brown bears. Acknowledging and broadening models based on foraging theories is more likely to foster novel discoveries and insights into the role of polyphagous species in ecosystems and we encourage this approach.

Circadian gene transcription plays a role in cellular metabolism in hibernating brown bears, Ursus arctos.

Hibernation is a highly seasonal physiological adaptation that allows brown bears (Ursus arctos) to survive extended periods of low food availability. Similarly, daily or circadian rhythms conserve energy by coordinating body processes to optimally match the environmental light/dark cycle. Brown bears express circadian rhythms in vivo and their cells do in vitro throughout the year, suggesting that these rhythms may play important roles during periods of negative energy balance. Here, we use time-series analysis of RNA sequencing data and timed measurements of ATP production in adipose-derived fibroblasts from active and hibernation seasons under two temperature conditions to confirm that rhythmicity was present. Culture temperature matching that of hibernation body temperature (34 °C) resulted in a delay of daily peak ATP production in comparison with active season body temperatures (37 °C). The timing of peaks of mitochondrial gene transcription was altered as were the amplitudes of transcripts coding for enzymes of the electron transport chain. Additionally, we observed changes in mean expression and timing of key metabolic genes such as SIRT1 and AMPK which are linked to the circadian system and energy balance. The amplitudes of several circadian gene transcripts were also reduced. These results reveal a link between energy conservation and a functioning circadian system in hibernation.

The bear necessities: A sensitive qPCR assay for bear DNA detection from bile and derived products to complement wildlife forensic enforcement.

Demand for bear bile, a prized component of traditional Asian medicines, threaten Asiatic and sun bear population sustainability. While laws exist to prevent poaching and trafficking of bear parts and derivatives, smuggling persists with demand extending to surrogate species, including American black bears (Ursus americanus). Mitochondrial DNA (mtDNA) sequencing can identify products putatively containing biological bear material but can be undermined by PCR inhibitors in bile and a lack of sensitivity at trace levels. Quantitative PCR (qPCR) assays can be used to distinguish between closely related target species, while concomitantly evaluating inhibition and false negative results in low quality/quantity DNA applications. Herein, we develop a multiplexed qPCR assay to detect and differentiate among bear species, including highly diluted bile samples mixed within liquors as common dilutants. The assay detects as little as 10 locus copies/reaction of bear DNA with 95% confidence, distinguishing among sun, Asiatic and American black bears. Demonstrating the sensitivity and applicability of this assay in context of current bile mixture recipes, dilutions of 1:5,000 bile with ethanol, red wine, and spirits, all yielded clear quantifiable detections, where our data suggests as little as 1 drop of bile per 750 mL bottle of alcohol would still exceed the limits of detection (e.g., 1:15000 dilution or <0.05 mL bile per 750 mL bottle). Overall, this study provides a rapid, sensitive, and specific test to identify and distinguish among bear species commonly used for bile production to aid wildlife enforcement applications.

Biotransformed bear bile powder ameliorates diet-induced nonalcoholic steatohepatitis in mice through modulating arginine biosynthesis via FXR/PXR-PI3K-AKT-NOS3 axis.

NASH is a highly prevalent metabolic syndrome that has no specific approved agents up to now. BBBP, which mainly contains bile acids, possess various pharmacological properties and some bile acids are available for NASH treatment. Herein, the therapeutic effects and underlying mechanisms of BBBP against NASH were systemically evaluated. In this study, mice received an HFHS diet over a 20-week period to induce NASH with or without BBBP intervention were used to evaluate the effect and underlying mechanisms of BBBP against NASH. Our results demonstrated that BBBP attenuated hepatic steatosis, reduced body weight gain and lipid concentrations, and improved sensitivity to insulin and tolerance to glucose in mice fed an HFHS diet. Metabolomics and transcriptomic analysis revealed that BBBP suppressed the arginine biosynthesis by up-regulating NOS3 expression and the PI3K-Akt signaling pathway was also regulated by BBBP, as indicated by 55 DEGs. Bioinformatic analysis predicted the regulatory effect of the FXR/PXR-PI3K-AKT-NOS3 axis on arginine biosynthesis-related metabolites. These results were further confirmed by the significantly increased mRNA and protein levels of NOS3, PI3K (Pik3r2), and AKT1. And the increased levels of arginine biosynthesis related-metabolites, such as urea, aspartic acid, glutamic acid, citrulline, arginine, and ornithine, were confirmed accurately based on targeted metabolomics analysis. Together, our study uncoded the complicated mechanisms of anti-NASH activities of BBBP, and provided critical evidence inspiring the discovery of innovative therapies based on BBBP in the treatment of NASH.

Spotlight on iron and ferroptosis: research progress in diabetic retinopathy.

Iron, as the most abundant metallic element within the human organism, is an indispensable ion for sustaining life and assumes a pivotal role in governing glucose and lipid metabolism, along with orchestrating inflammatory responses. The presence of diabetes mellitus (DM) can induce aberrant iron accumulation within the corporeal system. Consequentially, iron overload precipitates a sequence of important adversities, subsequently setting in motion a domino effect wherein ferroptosis emerges as the utmost pernicious outcome. Ferroptosis, an emerging variant of non-apoptotic regulated cell death, operates independently of caspases and GSDMD. It distinguishes itself from alternative forms of controlled cell death through distinctive morphological and biochemical attributes. Its principal hallmark resides in the pathological accrual of intracellular iron and the concomitant generation of iron-driven lipid peroxides. Diabetic retinopathy (DR), established as the predominant cause of adult blindness, wields profound influence over the well-being and psychosocial strain experienced by afflicted individuals. Presently, an abundance of research endeavors has ascertained the pervasive engagement of iron and ferroptosis in the microangiopathy inherent to DR. Evidently, judicious management of iron overload and ferroptosis in the early stages of DR bears the potential to considerably decelerate disease progression. Within this discourse, we undertake a comprehensive exploration of the regulatory mechanisms governing iron homeostasis and ferroptosis. Furthermore, we expound upon the subsequent detriments induced by their dysregulation. Concurrently, we elucidate the intricate interplay linking iron overload, ferroptosis, and DR. Delving deeper, we engage in a comprehensive deliberation regarding strategies to modulate their influence, thereby effecting prospective interventions in the trajectory of DR's advancement or employing them as therapeutic modalities.

Bear bile powder alleviates Parkinson's disease-like behavior in mice by inhibiting astrocyte-mediated neuroinflammation.

Parkinson's disease (PD) is a common neurodegenerative disease in middle-aged and elderly people. In particular, increasing evidence has showed that astrocyte-mediated neuroinflammation is involved in the pathogenesis of PD. As a precious traditional Chinese medicine, bear bile powder (BBP) has a long history of use in clinical practice. It has numerous activities, such as clearing heat, calming the liver wind and anti-inflammation, and also exhibits good therapeutic effect on convulsive epilepsy. However, whether BBP can prevent the development of PD has not been elucidated. Hence, this study was designed to explore the effect and mechanism of BBP on suppressing astrocyte-mediated neuroinflammation in a mouse model of PD. PD-like behavior was induced in the mice by intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) (30 mg·kg-1) for five days, followed by BBP (50, 100, and 200 mg·kg-1) treatment daily for ten days. LPS stimulated rat C6 astrocytic cells were used as a cell model of neuroinflammation. THe results indicated that BBP treatment significantly ameliorated dyskinesia, increased the levels of tyrosine hydroxylase (TH) and inhibited astrocyte hyperactivation in the substantia nigra (SN) of PD mice. Furthermore, BBP decreased the protein levels of glial fibrillary acidic protein (GFAP), cyclooxygenase 2 (COX2) and inducible nitric oxide synthase (iNOS), and up-regulated the protein levels of takeda G protein-coupled receptor 5 (TGR5) in the SN. Moreover, BBP significantly activated TGR5 in a dose-dependent manner, and decreased the protein levels of GFAP, iNOS and COX2, as well as the mRNA levels of GFAP, iNOS, COX2, interleukin (IL) -1ß, IL-6 and tumor necrosis factor-α (TNF-α) in LPS-stimulated C6 cells. Notably, BBP suppressed the phosphorylation of protein kinase B (AKT), inhibitor of NF-κB (IκBα) and nuclear factor-κB (NF-κB) proteins in vivo and in vitro. We also observed that TGR5 inhibitor triamterene attenuated the anti-neuroinflammatory effect of BBP on LPS-stimulated C6 cells. Taken together, BBP alleviates the progression of PD mice by suppressing astrocyte-mediated inflammation via TGR5.

Characteristics of mesenchymal stem cells and their exosomes derived from giant panda (Ailuropoda melanoleuca) endometrium.

Conservation of genetic resources is an important way to protect endangered species. At present, mesenchymal stem cells (MSCs) have been isolated from the bone marrow and umbilical cords of giant pandas. However, the types and quantities of preserved cell resources were rare and limited, and none of MSCs was derived from female reproductive organs. Here, we first isolated MSCs from the endometrium of giant panda. These cells showed fibroblast morphology and expressed Sox2, Klf4, Thy1, CD73, CD105, CD44, CD49f, and CD105. Endometrium mesenchymal stem cells (eMSCs) of giant panda could induce differentiation into three germ layers in vitro. RNA-seq analysis showed that 833 genes were upregulated and 716 genes were downregulated in eMSCs compared with skin fibroblast cells. The results of GO and the KEGG analysis of differentially expressed genes (DEGs) were mainly focused on transporter activity, signal transducer activity, pathways regulating pluripotency of stem cells, MAPK signaling pathway, and PI3K-Akt signaling pathway. The genes PLCG2, FRK, JAK3, LYN, PIK3CB, JAK2, CBLB, and MET were identified as hub genes by PPI network analysis. In addition, the exosomes of eMSCs were also isolated and identified. The average diameter of exosomes was 74.26 ± 13.75 nm and highly expressed TSG101 and CD9 but did not express CALNEXIN. A total of 277 miRNAs were detected in the exosomes; the highest expression of miRNA was the has-miR-21-5p. A total of 14461 target genes of the whole miRNAs were predicted and proceeded with functional analysis. In conclusion, we successfully isolated and characterized the giant panda eMSCs and their exosomes, and analyzed their functions through bioinformatics techniques. It not only enriched the conservation types of giant panda cell resources and promoted the protection of genetic diversity, but also laid a foundation for the application of eMSCs and exosomes in the disease treatment of giant pandas.

Epidemiology Study of Trichinella Spiralis Infection in Tyumen Region.

Trichinosis is a parasitic infection with worldwide distribution, which is caused by consuming pork or other meats containing cystic larvae of the parasitic nematode Trichinella Spiralis. This study aimed to investigate the status of infection Trichinella Spiralis in domestic and wild animals. To study the spread of trichinelles in animals, a retrospective analysis was conducted based on the study of research journals and conducted their research methods of compressor trichinelloscopy (microscopic) and digestion of samples in artificial gastric juice (biochemical). A total of 17 positive samples were detected for trichinellosis during the observation period, of which 58.8% belonged to a badger (Meles Meles), and 35.3% to the brown bear (Ursusarctos), and only 5.9% of wild boar (Susscrofa). The mean long-term extent of infection belonged to badgers (18.2%), bears (7.9%), and wild boars (0.05%). The study found that between 2015 and 2020, seventeen Trichinella cases were recorded among wildlife in the Tyumen region and the Khanty-Mansi Autonomous Region. The number of annual Trichinella detection cases was declining, indicating the effectiveness of veterinary services. This study determined that the primary source of infection was bears, badgers, and wild boars. Among the 17 positive samples, 58.8% belonged to the badger, 35.3% to the bear, and only 5.9% to the wild boar.

Stress and reproductive hormones in hair associated with contaminant metal(loid)s of European brown bear (Ursus arctos).

Environmental contaminants like arsenic (As), cadmium (Cd), mercury (Hg) or lead (Pb) may disrupt hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal (HPG) axes due to their endocrine toxicity potential. Resulting long-term physiological stress or adverse effects on wildlife reproduction and ontogeny may cause detrimental effects at the individual and population levels. However, data on environmental metal(loid)s' impact on reproductive and stress hormones in wildlife, especially large terrestrial carnivores, are scarce. Hair cortisol, progesterone and testosterone concentrations were quantified and modelled with hair As, Cd, total Hg, Pb, biological, environmental and sampling factors to test for potential effects in free-ranging brown bears (Ursus arctos) from Croatia (N = 46) and Poland (N = 27). Testosterone in males (N = 48) and females (N = 25) showed positive associations with Hg and an interaction between Cd and Pb, but a negative association with interaction between age and Pb. Higher testosterone was found in hair during its growth phase compared to quiescent phase. Body condition index was negatively associated with hair cortisol and positively associated with hair progesterone. Year and conditions of sampling were important for cortisol variation, while maturity stage for progesterone variation (lower concentrations in cubs and yearlings compared to subadult and adult bears). These findings suggest that environmental levels of Cd, Hg and Pb might influence the HPG axis in brown bears. Hair was shown to be a reliable non-invasive sample for investigating hormonal fluctuations in wildlife while addressing individual and sampling specificities.

Taming the polar bear: Ten tips to manage posterior polar cataract.

Background: Posterior polar cataracts are challenging even for skilled cataract surgeons due to the high risk of posterior capsule rupture and vitreous loss during cataract surgery; hence, it is important to know how to manage such cases. Purpose: In this video, we describe the necessary precautions and steps to be taken to prevent and manage complications in phacoemulsification cataract surgery for posterior polar cataracts. Synopsis: The video contains ten tips to follow to avoid complications while performing phacoemulsification cataract surgery in patients with posterior polar cataracts and includes preoperative identification on slit-lamp examination, size of capsulorhexis, avoidance of hydrodissection, technique of nucleus management, viscoelastic injection to keep the anterior chamber formed, epinucleus and cortical matter removal, posterior capsular rupture management, anterior vitrectomy, and intraocular lens (IOL) implantation in eyes with posterior capsular rupture. Highlights: The video highlights ten different steps to be followed in the surgical management of patients with posterior polar cataract which, if followed meticulously, can give excellent outcomes in these patients. Conclusion: Posterior polar cataracts can be managed with phacoemulsification, with good visual outcomes if these precautions are followed. Video link: https://youtu.be/TeoLckE83xM. Additional information: Won Best Educational Video in a contest by phacotraining.org.

Novel polyomaviruses identified in fecal samples from four carnivore species.

Polyomaviruses are oncogenic viruses that are generally thought to have co-evolved with their hosts. While primate and rodent polyomaviruses are increasingly well-studied, less is known about polyomaviruses that infect other mammals. In an effort to gain insight into polyomaviruses associated with carnivores, we surveyed fecal samples collected in the USA from bobcats (Lynx rufus), pumas (Puma concolor), Canada lynxes (Lynx canadensis), and grizzly bears (Ursus arctos). Using a viral metagenomic approach, we identified six novel polyomavirus genomes. Surprisingly, four of the six genomes showed a phylogenetic relationship to polyomaviruses found in prey animals. These included a putative rabbit polyomavirus from a bobcat fecal sample and two possible deer-trophic polyomaviruses from Canada lynx feces. One polyomavirus found in a grizzly bear sample was found to be phylogenetically distant from previously identified polyomaviruses. Further analysis of the grizzly bear fecal sample showed that it contained anelloviruses that are known to infect pigs, suggesting that the bear might have preyed on a wild or domestic pig. Interestingly, a polyomavirus genome identified in a puma fecal sample was found to be closely related both to raccoon polyomavirus 1 and to Lyon-IARC polyomavirus, the latter of which was originally identified in human saliva and skin swab specimens but has since been found in samples from domestic cats (Felis catus).

The prevalence, classification, radiological and arthroscopic findings of intratendinous subscapularis tears.

PURPOSE: To investigate the clinical characteristics of intratendinous subscapularis (inSSC) tears. METHODS: Retrospectively, 69 patients with arthroscopically confirmed inSSC tears were identified from 2018 to 2019. Preoperatively and at final follow-up, thorough physical examination was performed and clinical outcomes (American Shoulder and Elbow Surgeons [ASES] score; University of California, Los Angeles [UCLA] score; visual analogue scale [VAS] for pain; and Simple Shoulder Test [SST]) were recorded. Features of pre-operative magnetic resonance image (MRI) such as high signalling within the tendon substance, communication to the bicipital groove and long head of biceps tendon (LHBT) lesions were investigated. Characteristics of arthroscopic view were investigated. Bear-hug and internal rotation resistance test at 90° abduction and external rotation (IRRT90°) test were used to assess the SSC strength. RESULTS: The mean follow-up was 2.4 (2-3) years. The prevalence of arthroscopically confirmed inSSC tears was 69/675 (10.2%) among arthroscopic rotator cuff repairs. Pre-operative physical examination found positive IRRT90° and bear-hug test in 41/60 (68.3%) and 42/69 (60.8%) patients, respectively. The Cohen kappa coefficient was interpreted to be substantial for the evaluation of all MRI parameters. According to the conditions of LHBT, inSSC tears were classified into 3 types: type I: without LHBT subluxation and tear; type II: with LHBT subluxation or tears and type III: with LHBT dislocation. At final follow-up, mean ASES, UCLA, VAS, and SST scores improved significantly from mean of 50.6 ± 14.7, 19.4 ± 3.07, 6.2 ± 2.0, and 6.1 ± 2.5 to mean of 90.7 ± 9.5, 32.2 ± 1.8, 1.4 ± 1.2 and 9.8 ± 2.2, respectively (P < 0.001). Bilateral symmetric strength was found by bear-hug and IRRT90° test in all patients postoperatively. CONCLUSION: Understanding features of pre-operative MRI, physical examination and arthroscopic view is helpful to identify inSSC tears. Arthroscopic repair yielded satisfactory clinical outcomes in patients with inSSC tears. LEVEL OF EVIDENCE: Level IV.