Search Results (125)

The collection of perivitelline fluid (PVF) from early-stage post-activation zebrafish (Danio rerio) eggs/embryos poses a significant challenge owing to the liability of the egg/embryo to sustain damage and rupture during handling. Rupture of the blastoderm and/or yolk presents a major risk of PVF sample contamination. Previous efforts to extract PVF at such early stages have employed formalin fixation to enhance the structural integrity of the blastoderm and yolk syncytial layer, thereby reducing the likelihood of contamination. While this approach successfully mitigates blastoderm and yolk rupture, formaldehyde fixation may cause issues with downstream proteomic analyses. Recent findings indicate that zebrafish PVF contains a range of maternally inherited proteins involved in innate immune defence. However, current extraction methods compromise the reliability of downstream protein analyses, raising concerns that fixation-induced protein crosslinking may obscure the presence of maternally inherited proteins during the earliest stages of development. The micro-aspiration technique described here allows for the precise extraction of PVF from living, water-activated eggs with minimal disruption to the blastodisc and yolk. This method reduces the risk of contamination from other non-target proteinaceous egg sources and eliminates the need for formalin fixation, thereby improving the integrity of PVF samples and enhancing the reliability of subsequent downstream analyses. Full article

The broad-spectrum insect growth regulator (IGR) and insecticide 2-((1-(4-Phenoxyphenoxy)propan-2-yl)oxy)pyridine (MPEP; also known as pyriproxyfen) is increasingly being used to address public health programs for vector control, initiated by the spread of Zika virus in 2015–2016. While considered relatively safe for humans under normal conditions, limited toxicology data are available. Current studies were undertaken to address the data gap regarding potential immunotoxicity of MPEP, with particular emphasis on host resistance to viral infection. Hsd:Harlan Sprague Dawley SD^® rats were treated for 28 days by oral gavage with doses of 0, 62.5, 125, 250 or 500 mg/kg/day of MPEP in corn oil. There was a dose-dependent increase in liver weights which is consistent with the liver playing a dominant role in MPEP metabolism. However, no histological correlates were observed. Following treatment, rats were subjected to a battery of immune tests as well as an established rat model of influenza virus infection to provide a comprehensive assessment of immune function and host resistance. While several of the immune tests showed minor exposure-related changes, evidenced by negative dose–response trends, most did not show significant differences in any of the MPEP treatment groups relative to vehicle control. Most notable was a negative trend in pulmonary mononuclear cell phagocytosis with increases in dose of MPEP. There was also a positive trend in early humoral immune response (5 days after immunization) to keyhole limpet hemocyanin (KLH) as evidenced by increased serum anti-KLH IgM antibodies which was followed later (14 days following immunization) by decreasing trends in anti-KLH IgM and IgG antibody levels. However, MPEP treatment had no effect on the ability of rats to clear the influenza virus nor the T-dependent IgM and IgG antibody response to the virus. The lack of effects of MPEP on host resistance to influenza suggests the immune effects were minimal and unlikely to present a hazard with respect to susceptibility to respiratory viral infection. Full article

This paper studies a class of two-player all-pay contests with externalities that encompass a general version of duopoly price competition. This all-pay contest formulation puts little restriction on production technologies, demand, and demand rationing. There are two types of possible equilibria: In the first type of equilibrium, the lower bound to pricing is the same for each firm, and the probability of any pricing tie above this price is zero. Each firm’s equilibrium expected profit is their monopoly profit at the lower bound price. In the second type of equilibrium, one firm prices at the lower bound of the other firm’s average cost and other firm prices according to a non-degenerate mixed strategy. This type of equilibrium can only occur if production technologies are sufficiently different across firms. We derive necessary and sufficient conditions for the existence of pure strategy equilibrium and use these conditions to demonstrate the fragility of deterministic outcomes in pricing games. Full article

Anthropogenic influences have increased global warming and eutrophication, escalating the frequency and severity of harmful cyanobacterial blooms (cHABs) in freshwater ecosystems. These blooms release cyanopeptides, a diverse class of bioactive compounds with varying acute and chronic toxicities upon ingestion. To date, research has prioritized acutely toxic cyanopeptides like microcystins. As a result, significantly less is known about other freshwater cyanopeptides. This review highlights six understudied cyanopeptide classes, anabaenopeptins, cyanopeptolins, aeruginosamides, aeruginosins, microginins, and cyclamides, and provides a comprehensive overview of their molecular structures, toxicological profiles, environmental concentrations, and known degradation pathways. Given the potential toxicity, increased environmental abundance, and environmental stability of many cyanopeptides in freshwater sources, further research is needed to understand if degraded cyanopeptides are still biologically active prior to entering drinking water to ensure public health. Full article

Tritrichomonas foetus is a sexually transmitted protozoan that causes early embryonic death in cattle. A challenge in trichomonosis research is that in vivo studies of treatments, diagnostic strategies, and vaccines are severely hampered by the logistical challenge and cost of maintaining adult bulls. Since natural infections are diagnosed in postpubescent animals, the paradigm is that only mature breeding bulls can be infected. In this study, we hypothesized that prepubescent bull calves could be artificially infected with T. foetus trophozoites for the purpose of conducting research trials. Initial attempts to directly infect bull calves with two different parasite isolates resulted in the sporadic and transient detection of parasite DNA but not culturable trophozoites. In vitro and in vivo studies suggested that urine directly inhibited trophozoites, likely by osmotic damage and mechanical flushing action. Studies utilizing a perineal urethrostomy to remove urine flow from the prepuce resulted in the ability to colonize the prepuce, with live organisms being cultured for as long as 15 days post-inoculation. Future studies optimizing this technique have the potential to accelerate the pace of bovine trichomonosis research and may have applications in the study of human trichomoniasis. Full article

Objectives: This study investigated the effects of 2-week ingestion of hemp fiber (high and low doses) versus placebo bars on gut permeability and plasma metabolite shifts during recovery from 2.25 h intensive cycling. Hemp hull powder is a rich source of two bioactive compounds, N-trans-caffeoyl tyramine (NCT) and N-trans-feruloyl tyramine (NFT), with potential gut health benefits. Methods: The study participants included 23 male and female cyclists. A three-arm randomized, placebo-controlled, double-blind, crossover design was used with two 2-week supplementation periods and 2-week washout periods. Supplement bars provided 20, 5, or 0 g/d of hemp hull powder. Participants engaged in an intensive 2.25 h cycling bout at the end of each of the three supplementation periods. Five blood samples were collected before and after supplementation (overnight fasted state), and at 0 h-, 1.5 h-, and 3 h-post-exercise. Five-hour urine samples were collected pre-supplementation and post-2.25 h cycling after ingesting a sugar solution containing 5 g of lactulose, 100 mg of ¹³C mannitol, and 1.9 g of mannitol in 450 mL of water. An increase in the post-exercise lactulose/¹³C mannitol ratio (L:¹³CM) was used as the primary indicator of altered gut permeability. Other outcome measures included muscle damage biomarkers (serum creatine kinase, myoglobin), serum cortisol, complete blood cell counts, and shifts in plasma metabolites using untargeted metabolomics. Results: No trial differences were found for L:¹³CM, cortisol, blood cell counts, and muscle damage biomarkers. Orthogonal partial least-squares discriminant analysis (OPLSDA) showed distinct trial differences when comparing high- and low-dose hemp fiber compared to placebo supplementation (R2Y = 0.987 and 0.995, respectively). Variable Importance in Projection (VIP) scores identified several relevant metabolites, including 3-hydroxy-4-methoxybenzoic acid (VIP = 1.9), serotonin (VIP = 1.5), 5-hydroxytryptophan (VIP = 1.4), and 4-methoxycinnamic acid (VIP = 1.4). Mummichog analysis showed significant effects of hemp fiber intake on multiple metabolic pathways, including alpha-linolenic acid, porphyrin, sphingolipid, arginine and proline, tryptophan, and primary bile acid metabolism. Conclusions: Hemp fiber intake during a 2-week supplementation period did not have a significant effect on post-exercise gut permeability in cyclists (2.25 h cycling bout) using urine sugar data. On the contrary, untargeted metabolomics showed that the combination of consuming nutrient-rich hemp fiber bars and exercising for 135 min increased levels of beneficial metabolites, including those derived from the gut in healthy cyclists. Full article

Bile acids (BAs) are important signaling molecules in the gastrointestinal (GI) tract and are associated with health and disease in humans and animals. Intestinal bacteria transform BA through deconjugation, dehydroxylation, and epimerization reactions, producing various isoforms, many of which have not been investigated in companion animal diseases. We aimed to develop and analytically validate a novel liquid chromatography–tandem mass spectrometry (LC-MS/MS) method for the quantification of 30 BAs in dog feces, with a simple extraction procedure and on-line solid-phase extraction. Validation demonstrated good accuracy, precision, sensitivity, spiking recovery, dilution, and stability for 29 BAs. The method was applied to fecal samples from healthy dogs (H; n = 121) and dogs with chronic enteropathy (CE; n = 58). The immediate and downstream products of bacterial 7α-dehydroxylation reactions with cholic acid were lower in concentration in dogs with CE when compared to healthy dogs (deoxycholic acid, 3-oxo-deoxycholic acid, and 12-oxo-lithocholic acid; q < 0.001). Across all fecal samples, the products of hydroxysteroid dehydrogenase (including oxo- and iso-BA) made up an average of 30% of the total measured fecal BA pool (glycine-BA, 0.1%; taurine-BA, 2.2%; unconjugated BA, 53%). Full article

Background/Objectives: A functional liver is vital for normal protein metabolism. Alterations of circulating amino acid (AA) concentrations have previously been reported in dogs with hepatocellular carcinoma, chronic hepatitis, and hepatocutaneous syndrome. The purpose of this study was to compare serum AA profiles between dogs with a congenital portosystemic shunt (CPSS) and healthy control dogs. Methods: Serum samples were collected from 50 dogs with an extrahepatic congenital portosystemic shunt (eCPSS) and 10 dogs with an intrahepatic congenital portosystemic shunt (iCPSS) at time of surgical intervention and from 21 healthy control dogs. Serum AA and other nitrogenous compounds were measured with a dedicated amino acid analyzer. The concentration of each AA was compared between groups using a Kruskal–Wallis test followed by Dunn’s multiple comparisons tests, as appropriate. The Benjamini–Hochberg procedure was used to control for false discovery. Significance was set at q < 0.05. Results: Compared to healthy controls, dogs with a CPSS had significantly increased serum concentrations of ammonia, asparagine, glutamic acid, histidine, phenylalanine, serine, and tyrosine and had significantly decreased concentrations of isoleucine, leucine, threonine, urea, and valine. There were no significant differences in serum AA concentrations between dogs with an eCPSS and dogs with an iCPSS. Conclusions: Dogs with a CPSS had altered serum AA concentrations compared to healthy control dogs, including decreased branched-chain amino acids (BCAAs) and increased aromatic amino acids (AAAs). In summary, serum AA profiles can differentiate dogs with a CPSS from healthy dogs but not dogs with an eCPSS from dogs with an iCPSS. Full article

Background: Genetic causes of chronic diseases, once considered rare in adult-onset disease, now account for between 10 and 20% of cases of chronic kidney disease (CKD). Confirming a genetic diagnosis can influence disease management; however, the utility of genetic testing in older adults remains poorly understood, partly due to age-based restrictions on testing access. To better evaluate the diagnostic yield and clinical utility of genetic testing in this population, we analyzed data from adults aged ≥50 years with CKD who were assessed in a specialized kidney genetics clinic. Methods: We studied a cohort of 125 adults with CKD aged ≥50 years at the time of genetic testing. Genetic testing included gene panels targeting disease-related genes based on clinical phenotype, and/or exome sequencing for additional monogenic causes if the initial panel testing was inconclusive. Results: Pathogenic variants in disease-related genes were identified in 38% of patients. The highest diagnostic yield (48%) was in patients aged 50–54 years. The most common diagnosis post-testing was glomerulopathies (32%). Clinical utility, shown through the case series, included modifications to treatment and clinical management, as well as a reduction in the diagnostic odyssey. Conclusions: Our findings from a dedicated Kidney Genetics Clinic show that genetic testing in adults ≥50 years with CKD has significant diagnostic and clinical utility. These results support guideline recommendations that there should be no upper age limit for genetic testing. Future research in unselected CKD populations is needed to establish the broader applicability and feasibility of genetic testing in older adults. Full article

Cloning from historically cryopreserved cells offers a potential means to restore lost genetic variation or increase the representation of particular lineages within bottlenecked species, provided such biobanked materials are archived for such genetic rescue applications. One species for which cloning can provide genetic management benefits is Przewalski’s horse, Equus przewalskii. All ~1800 living Przewalski’s horses, distributed across ex situ breeding facilities and in situ reintroduction sites, are descended from one or more of the five founder lineages established by the 12 horses captured from the wild between 1898 and 1947. Since the 1970s, the San Diego Zoo Wildlife Alliance Biodiversity Bank’s Frozen Zoo^® (Escondido, CA, USA) has biobanked cells or tissues of 575 individuals spanning many generations. A pedigree analysis of a subset of deceased individuals represented in the San Diego Zoo Wildlife Alliance Biodiversity Bank’s Frozen Zoo^® revealed an underrepresented male that lived from 1975 to 1998, Studbook Number 615 (also known as Kuporovitch), who would be of high value for breeding if cloned. Here, we report that two healthy clones were produced from this cell line using cross-species somatic cell nuclear transfer from 2020 to 2023. Their identification as clones was verified by a standard horse-pedigree genotyping panel, and, for one clone, a whole genome sequencing comparison to the original donor was performed. This is the first time that multiple healthy clones surviving the perinatal period have been produced for an endangered species. Full article

Background/Objectives: The relevance of adult attachment security for physical and emotional wellbeing is increasingly evident. Developing a better understanding of the interpersonal antecedents of secure attachment in childhood and adolescence could enable opportunities for its promotion when attachment styles are more easily modifiable. Methods: Data from 3648 participants in a longitudinal birth cohort study were examined. At 21 years, participants completed the confidence (in self and others) subscale of the Attachment Style Questionnaire, a measure of attachment security. Path analysis was used to longitudinally examine the influence of maternal and child-reported interpersonal variables at birth, 5, and 14 years on attachment security in early adulthood. Results: Two pathways were identified. Firstly, child and family social relations at birth and 5 years predicted attachment security via the number of the child’s close friends at 14 years (β = 0.11, p < 0.001). Secondly, attuned caregiving at 14 years predicted attachment security via the recalled experiences of parental care up to 16 years, measured at 21 years (β = 0.28, p < 0.001). Greater adolescent family satisfaction directly predicted increased attachment security in early adulthood (β = 0.10, p < 0.001). Conclusions: Child and family social relationships from birth and throughout childhood and adolescence, along with attuned caregiving, led to increased attachment security in early adulthood. Public health and policy initiatives aimed at strengthening social support systems for caregivers and their children throughout childhood, and increasing the uptake of parenting programmes aimed at strengthening attuned caregiving, may lead to long-term improvements in the attachment security of offspring. Full article

The rising global energy demand, alongside concerns regarding environmental deterioration due to the use of fossil fuels, has spurred extensive investigation into renewable energy alternatives. Biomass-derived biodiesel, especially from lesser-known oil sources, emerges as a promising option. This research focuses on analyzing the fatty acid methyl esters (FAMEs) derived from Kariya (Hildegardia barteri (Mast.) Kosterm) seed oil through basic catalytic transesterification using gas chromatography–flame ionization detector (GC–FID) analysis, assessing its potential as a biodiesel feedstock. Oil extraction from Kariya seeds was carried out using three solvents (n-hexane, ethanol, and a 1:1 blend of hexane and ethanol), followed by transesterification with methanol. Gas chromatography–mass spectrometry (GC–MS) and GC–FID analyses were utilized to identify and quantify FAMEs in the resulting biodiesel. The results revealed various FAMEs, including methyl myristate, methyl palmitate, methyl stearate, methyl oleate, methyl linoleate, and methyl linolenate. Significant differences in FAME composition were observed among the samples, with hexane–ethanol Kariya oil biodiesel (HE-KOB) showing the highest FAME content (76.1%). This combination of solvents exhibited synergistic effects on the composition of HE-KOB, suggesting potential optimization strategies for biodiesel production. Fourier transform infrared spectroscopy (FTIR) provided additional insights into the molecular composition of the biodiesel samples, confirming their biodiesel nature through the identified functional groups such as methyl, methylene, hydrocarbon, ester, aldehyde, and alkene. Thermogravimetric analysis (TGA) for thermal decomposition also gave an insight into FAME composition and its contribution to the degree of conversion of biodiesel to energy. These findings highlight the feasibility of utilizing Kariya seed oil as a biodiesel feedstock, emphasizing the importance of solvent selection and transesterification conditions in optimizing FAME yield and composition. This research contributes to the exploration of underutilized oil sources for sustainable biodiesel production, aligning with the global shift towards cleaner and renewable energy sources. Full article

Background: Burn injuries can require hospitalization, operations, and long-term reconstruction. Burn-injured patients can experience short- or long-term disability. We investigated lost workdays (LWDs), short-term disability (STD), and long-term disability (LTD) in the 12-month period following a burn injury. Methods: An observational cohort study was conducted using a commercial claims database, IBM^® MarketScan^®. Patients aged ≤65 years with an ICD-10 burn diagnosis from 2018 to 2019 were included. The International Classification of Diseases, 10th Revision (ICD-10), procedure and Current Procedural Terminology (CPT) codes were used to identify patients undergoing burn-related operations. Patients were mapped to data tables for LWDs, STD, and LTD for the 12 months pre- and post-injury. Paired t-tests were employed to compare the pre- and post-injury outcomes. Results: We identified 1745 patients with burn diagnoses. Of those, 263, 1449, and 1448 patients had data available for LWDs, STD, and LTD, respectively. STD and LTD were reported by 8.1% and 0.0% of patients in the 12-month period pre-injury, respectively, and 20.3% and 1.0% of patients in the 12-month period post-injury, respectively. Average days of STD increased from 3.70 to 9.34 days following injury. Conclusions: Burn injuries are associated with increased STD and LTD utilization. Quantifying the impact of burn injuries on patients’ work will help us understand the economic implications of burns, which is a key area in burn research. Full article

Background: ALDH1L1 plays a crucial role in folate metabolism, regulating the flow of one-carbon groups through the conversion of 10-formyltetrahydrofolate to tetrahydrofolate and CO₂ in a NADP⁺-dependent reaction. The downregulation of ALDH1L1 promotes malignant tumor growth, and silencing of ALDH1L1 is commonly observed in many cancers. In a previous study, Aldh1l1 knockout (KO) mice were found to have an altered liver metabotype, including significant alterations in glycine and serine. Serine and glycine play crucial roles in pathways linked to cancer initiation and progression, including one-carbon metabolism. Objective/Methods: To further investigate the metabolic role of ALDH1L1, an untargeted metabolomic analysis was conducted on the liver and plasma of both KO and wild-type (WT) male and female mice. Since ALDH1L1 affects glycine- and serine-coupled metabolites and metabolic pathways, correlation analyses between liver glycine and serine with other liver or plasma metabolites were performed for both WT and KO mice. Significantly correlated metabolites were input into MetaboAnalyst 5.0 for pathway analysis to uncover metabolic pathways coupled with serine and glycine in the presence or absence of ALDH1L1 expression. Results: This analysis showed substantial alterations in pathways associated with glycine and serine following ALDH1L1 loss, including the amino acid metabolism, antioxidant pathways, fatty acid oxidation, and vitamin B5 metabolism. These results indicate the glycine- and serine-linked metabolic reprogramming following ALDH1L1 loss to support macromolecule biosynthesis and antioxidant defense. Additional research is required to further explore the correlation between specific alterations in these pathways and tumor growth, as well as to identify potential dietary interventions to mitigate the detrimental effects of ALDH1L1 loss. Full article

The pharmacokinetics of Δ⁹-tetrahydrocannabinol (Δ⁹-THC) has not been established in ruminants. Pharmacokinetic knowledge is important given feeding industrial hemp biomass has been shown to result in tissue residues post feeding in sheep. Due to a lack of testing and available data, a ‘maximum’ concentration of Δ⁹-THC has not been currently set for foods of animal origin. Consequently, this study was designed to gain a better understanding of how ruminants process Δ⁹-THC. Eight Merino ewes were administered with two per os (PO) doses of 88.5 mg Δ⁹-THC/kg bodyweight (BW) 12 h apart. Blood samples were collected periodically post dosing to determine the pharmacokinetics of Δ⁹-THC and subcutaneous fat biopsies were taken to investigate the deposition and elimination of Δ⁹-THC from sheep. An elimination half-life of 31.40 ± 13.87 h was identified, with residues persisting in the subcutaneous fat for 28 d in five of the eight sheep, before decreasing below the limit of detection in all sheep by 91 d. These results support the prolonged presence of Δ⁹-THC residues previously identified. Thus, imposing a practical withholding period for ruminants involved in the food chain may not be possible, with further research required to investigate how iHemp biomass may be safely fed to ruminants. Full article