Animal Tissues Research Articles

Zinc Oxide‐Enhanced Copper Sulfide Nanozymes Promote the Healing of Infected Wounds by Activating Immune and Inflammatory Responses

AbstractBacterial infection and an excessive inflammatory response are two major factors that affect the healing of infected wounds. The zinc oxide/copper sulfide (ZnO‐CuS) microspheres (MSs) developed in this work can kill bacteria and resist inflammation. ZnO‐CuS exhibits different enzyme‐like activities depending on pH. In acidic environments, ZnO‐CuS exhibits peroxidase‐like (POD‐like) activity and can convert hydrogen peroxide (H2O2) into hydroxyl radicals (•OH) for sterilization. Under neutral conditions, ZnO‐CuS removes reactive oxygen species (ROS) and can convert excess ROS into water and oxygen. The in vitro results of the antibacterial test demonstrate the pronounced disruption effect of ZnO‐CuS on the bacterial biofilm and cell membrane. The transcriptome sequencing results of wounded animal tissue reveal that ZnO‐CuS MSs increase the expression of proteins produced by immune cells, and reduce the expression levels of inflammatory factors at the wound site. Therefore, antimicrobial activity and rapid wound healing can be achieved by regulating the immune response and reducing the inflammatory response. The results from hemolysis, routine blood and blood biochemistry analyses demonstrate the excellent biosecurity of the ZnO‐CuS MSs.

Construction and evaluation of a new rat reference genome assembly, GRCr8, from long reads and long-range scaffolding

We report the construction and analysis of a new reference genome assembly forRattus norvegicus, the laboratory rat, a widely used experimental animal model organism. The assembly has been adopted as the rat reference assembly by the Genome Reference Consortium and is named GRCr8. The assembly has employed 40× Pacific Biosciences (PacBio) HiFi sequencing coverage and scaffolding using optical mapping and Hi-C. We used genomic DNA from a male BN/NHsdMcwi (BN) rat of the same strain and from the same colony as the prior reference assembly, mRatBN7.2. The assembly is at chromosome level with 98.7% of the sequence assigned to chromosomes. All chromosomes have increased in size compared with the prior assembly andk-mer analysis indicates that the subject animal is fully inbred and that the genome is represented as a single haploid assembly. Notable increases are observed in Chromosomes 3, 11, and 12 in the prospective rDNA regions. In addition, Chr Y has increased threefold in size and is more consistent with the rat karyotype than previous assemblies. Several other chromosomes have grown by the incorporation of sizable discrete new blocks. These contain highly repetitive sequences and encode numerous previously unannotated genes. In addition, centromeric sequences are incorporated in most chromosomes. Genome annotation has been performed by NCBI RefSeq, which confirms improvement in assembly quality and adds more than 1100 new protein coding genes. PacBio Iso-Seq data have been acquired from multiple tissues of the subject animal and are released concurrently with the new assembly to aid further analyses.

Baseline Raman Spectral Fingerprints of Zebrafish Embryos and Larvae

As a highly sensitive vibrational technique, Raman spectroscopy (RS) can provide valuable chemical and molecular data useful to characterise animal cell types, tissues and organs. As a label-free, rapid detection method, RS has been considered a valuable asset in forensics, biology and medicine. The technique has been applied to zebrafish for various purposes, including physiological, biochemical or bioaccumulation analyses. The available data point out its potential for the early diagnosis of detrimental effects elicited by toxicant exposure. Nevertheless, no baseline spectra are available for zebrafish embryos and larvae that could allow for suitable planning of toxicological assessments, comparison with toxicant-elicited spectra or mechanistic understanding of biochemical and physiological responses to the exposures. With this in mind, this work carried out a baseline characterisation of Raman spectra of zebrafish embryos and larvae throughout early development. Raman spectra were recorded from the iris, forebrain, melanocytes, heart, muscle and swim bladder between 24 and 168 h post-fertilisation. A chemometrics approach, based on partial least-squares discriminant analysis (PLS-DA), was used to obtain a Raman characterisation of each tissue or organ. In total, 117 Raman bands were identified, of which 24 were well represented and, thus, retained in the data analysed. Only three bands were found to be common to all organs and tissues. The PLS-DA provided a tentative Raman spectral fingerprint typical of each tissue or organ, reflecting the ongoing developmental dynamics. The bands showed frequencies previously assigned to collagen, cholesterol, various essential amino acids, carbohydrates and nucleic acids.

Raman spectroscopy and imaging in bio and life sciences

AbstractRaman spectroscopy is a well‐known technique to study different materials and determine their chemical composition. It is based on the inelastic scattering of light and provides a unique spectrum for the sample under study. The advances in lasers and detectors, their combination with imaging systems and the discovery of new phenomena have expanded the use of this technique in several research fields. In the particular case of biology and life sciences, it has been used to provide chemical and compositional information on plant and animal tissues, cells, biofluids, etc., with the advantage that the presence of water molecules normally does not cause interference in the measured signal.

Static headspace-gas chromatography with mass spectrometry for the assessment of the bioaccumulation of volatile organic compounds associated with microplastics in animal tissues

Static headspace-gas chromatography with mass spectrometry for the assessment of the bioaccumulation of volatile organic compounds associated with microplastics in animal tissues

Role of local angiotensin II signaling in bladder function.

Angiotensin II signaling plays a crucial role in many different diseases. Although it has been known for several decades that local angiotensin II signaling molecules are present in the bladder, the understanding of their functions there is still limited, especially compared with other organ systems such as cardiovascular and respiratory systems. This article reviews current literature regarding local angiotensin II signaling in the urinary bladder. By reviewing several decades of literature, the field has provided strong evidence to support the presence of local angiotensin II signaling in the bladder, including the expression of angiotensin type 1 receptor and angiotensin type 2 receptor in both human and animal tissues. In addition, evidence suggests a functional role of angiotensin type 1 receptor in mediating bladder contractions. In bladder disease models, angiotensin II signaling can be upregulated, and angiotensin type 1 receptor activity is associated with increases in inflammation, fibrosis, and oxidative stress. We also address the gaps in knowledge that remain in understanding local angiotensin II signaling in the bladder, including limitations on clinical translatability. Although there is a strong foundation regarding the local presence and role of angiotensin II signaling in the bladder, further research is needed to support translational applications.

High-performance biochar derived from the leaves of Quercus dentata thunb for triclosan removal

BackgroundTriclosan (TCS) is a common antimicrobial additive. Despite its low concentration, its frequent use and widespread application result in significant amounts of TCS entering the environment. In the environment, TCS undergoes photodegradation, producing harmful byproducts such as dioxin-like substances and chloroform, which are highly toxic. Due to TCS's lipophilic nature, it easily accumulates in animal tissues, ultimately posing a threat to human health. Therefore, there is an urgent need for a powerful and efficient method to remove TCS from water bodies. MethodsUsing discarded traditional Chinese medicine as raw material and KOH as an activator, biochar was prepared. The material was characterized, and its adsorption capacity for TCS under various conditions was evaluated. Significant FindingsCompared to the existing biochar materials' TCS adsorption capacity (13.9 mg/g-395.2 mg g-1), the KOH-modified biochar (KMBC) in this study demonstrated an exceptional adsorption capacity of 639.13 mg g-1 for TCS. KMBC can swiftly remove 98 % of TCS from water within 30 min, even with a minimal biochar concentration of 0.225 g/L, and it exhibits strong anti-interference capabilities. Most importantly, water treated with KMBC is virtually free of TCS, effectively mitigating its impact on environmental organisms.

Optimizing prolyl hydroxylation for functional recombinant collagen in Escherichia coli

Collagen, a key extracellular matrix component, is renowned for its biocompatibility, biodegradability, and bioactivity, finding wide applications in food, medicine, cosmetics, and industry. Recombinant collagen expression in Escherichia coli offers advantages such as shorter production cycles and lower costs compared to extraction from animal tissues, though it is known to lack essential post-translational modifications, such as proline hydroxylation, which are crucial for its stability and biological function. Studies have shown that certain prolyl hydroxylases, including BaP4H, DsP4H, and L593, exhibit relatively high modification efficiency in the E. coli expression system. However, structures and functions of recombinant human type III collagen after modification by three prolyl hydroxylases remain uncertain. In this study, we investigated the percentage of proline hydroxylation, hydroxylation sites, circular dichroism spectra, and biological functions of recombinant human type III collagen modified by various prolyl hydroxylases. The results indicated that the L593 exhibited the highest percentage of proline hydroxylation, and the percentage of proline hydroxylation was closely associated with the formation of the collagen triple helix, while the hydroxylation ratio of prolines is not positively correlated with the stability of the collagen triple helix structure. The biological function results showed that the cell adhesion of recombinant collagen 3-3(BaP4H) and 3-3(L593) was significantly enhanced, which was closely related to the triple helix structure of recombinant human type III collagen. Our study provides valuable insights into the industrial production and biological applications of collagen, enhancing its functional research and scalability.

Target-promoted catalytic DNA molecular circuit network coupled with endonuclease amplification for sensitive and label-free electrochemical aptamer antibiotic assay

Sarafloxacin (SAR) is a common antibiotic that accumulates in animal tissues, which potentially poses health risks to humans via ingestion. Sensitive detection of SAR in animal-derived foods is therefore critical. Traditional SAR detection methods based on HPLC or antibody immunoassays encounter the limitations of cost, sensitivity and operational simplicity. In this study, with the design of a new DNAzyme/catalytic hairpin assembly (CHA) molecular circuit network coupled with endonuclease amplification, we developed an electrochemical aptamer (AP) biosensor with high sensitivity for label-free SAR detection in milk. The sensor functions by specific binding of SAR to APs, which release DNAzyme sequences to initiate the catalytic DNAzyme/CHA molecular circuit network amplification for forming many ssDNAs and dsDNA duplexes. These sequences further hybridize with hairpin signal probes on sensor electrode to create favorable nicking sites for endonuclease, which cleaves hairpin signal probes to liberate lots of G-quadruplex strands to complex with and capture hemin. Subsequent hemin reduction by electrochemistry thus results in dramatically enhanced currents to achieve label-free detection of SAR in linear range between 10 pM and 80 nM with detection limit of 1.62 pM. Our sensor also shows satisfactory reproducibility, repeatability and stability, demonstrates high selectivity for the target SAR against other interfering antibiotics, e.g., norfloxacin, penicillin and gentamicin and can realize detection of low concentrations of SAR in diluted complex milk and human serum samples, thereby underscoring its promises for convenient and sensitive assay of different trace antibiotics.

P53/HIF-1α regulates neuronal aging and autophagy in spinal cord ischemia/reperfusion injury

ObjectionSpinal cord injury (SCI)-induced hindlimb dysfunction affects the physical and mental health of patients. There is growing evidence suggesting that the recovery capacity of elderly SCI patients is poorer than that of young individuals. However, the specific molecular mechanisms remain unclear. MethodsRNA expression profiles of SCI samples were collected from the GEO database, and key genes involved in the progression of SCI were identified by the limma package in R software. A diagnostic model based on SCIDEG was constructed using LASSO regression analysis. Subsequently, correlation analysis was conducted to identify biological pathways influenced by the key genes. Furthermore, SCI animal models were established in different age groups to examine the expression of relevant genes and verify the molecular mechanism of p53/HIF-1α axis. ResultsWe initially identified 34 ischemia-hypoxia-related genes potentially involved in the progression of SCI. Subsequently, we constructed a diagnostic model based on SCIDEGs using LASSO regression analysis. This model highlighted 9 key genes (TP53, SFTPA1, MASP2, KRT14, IL9, HIF1A, HGFAC, FUT7, and ALPP), which demonstrated high diagnostic accuracy in both the training set (AUC=1) and the validation set (AUC=0.855). Further cross-analysis with ischemia-reperfusion-related datasets confirmed the involvement of HIF1A and TP53. We also observed significant enrichment of HIF1A in organoids composed of mature neurons, which induced neuronal damage. In subsequent spinal cord injury animal models of different age groups, we found that HIF-1α expression was downregulated in the spinal cord tissues of elderly animals. Additionally, we discovered that TP53 activation induces cellular senescence in aging neurons and suppresses HIF-1α expression and autophagy levels within these cells. ConclusionIn summary, our study suggests that the p53/HIF-1α signaling pathway plays a critical role in regulating neuronal aging and autophagy in the pathogenesis of SCI. Importantly, HIF-1α may represent a promising therapeutic target for SCI treatment.

Pathological Alterations in Heart Mitochondria in a Rat Model of Isoprenaline-Induced Myocardial Injury and Their Correction with Water-Soluble Taxifolin

Mitochondrial damage and associated oxidative stress are considered to be major contributory factors in cardiac pathology. One of the most potent naturally occurring antioxidants is taxifolin, especially in its water-soluble form. Herein, the effect of a 14-day course of the peroral application of the water-soluble taxifolin (aqTAX, 15 mg/kg of body weight) on the progression of ultrastructural and functional disorders in mitochondria and the heart’s electrical activity in a rat model of myocardial injury induced with isoprenaline (ISO, 150 mg/kg/day for two consecutive days, subcut) was studied. The delayed ISO-induced myocardial damage was accompanied by an increase in the duration of RR and QT intervals, and long-term application of aqTAX partially restored the disturbed intraventricular conduction. It was shown that the injections of ISO lead to profound ultrastructural alterations of myofibrils and mitochondria in cardiomyocytes in the left ventricle myocardium, including the impairment of the ordered arrangement of mitochondria between myofibrils as well as a decrease in the size and the number of these organelles per unit area. In addition, a reduction in the protein level of the subunits of the respiratory chain complexes I-V and the activity of the antioxidant enzymes catalase, glutathione peroxidase, and Mn-SOD in mitochondria was observed. The application of aqTAX caused an increase in the efficiency of oxidation phosphorylation and a partial restoration of the morphometric parameters of mitochondria in the heart tissue of animals with the experimental pathology. These beneficial effects of aqTAX are associated with the inhibition of lipid peroxidation and the normalization of the enzymatic activities of glutathione peroxidase and Mn-SOD in rat cardiac mitochondria, which may reduce the oxidative damage to the organelles. Taken together, these data allow one to consider this compound as a promising cardioprotector in the complex therapy of heart failure.

Unveiling the Group A Streptococcus Vaccine-Based L-Rhamnose from Backbone of Group A Carbohydrate: Current Insight Against Acute Rheumatic Fever to Reduce the Global Burden of Rheumatic Heart Disease

Group A Streptococcus (GAS) is a widely distributed bacterium that is Gram-positive and serves as the primary cause of acute rheumatic fever (ARF) episodes. Rheumatic heart disease (RHD) is a sequela resulting from repeated ARF attacks which are also caused by repeated GAS infections. ARF/RHD morbidity and mortality rates are incredibly high in low- and middle-income countries. This is closely related to poor levels of sanitation which causes the enhanced incidence of GAS infections. Management of carditis in RHD cases is quite challenging, particularly in developing countries, considering that medical treatment is only palliative, while definitive treatment often requires more invasive procedures with high costs. Preventive action through vaccination against GAS infection is one of the most effective steps as a solution in reducing RHD morbidity and mortality due to curative treatments are expensive. Various developments of M-protein-based GAS vaccines have been carried out over the last few decades and have recently begun to enter the clinical stage. Nevertheless, this vaccination generates cross-reactive antibodies that might trigger ARF assaults as a result of the resemblance between the M-protein structure and proteins found in many human tissues. Consequently, the development of a vaccine utilizing L-Rhamnose derived from the poly-rhamnose backbone of Group A Carbohydrate (GAC) commenced. The L-Rhamnose-based vaccine was chosen due to the absence of the Rhamnose biosynthesis pathway in mammalian cells including humans thus this molecule is not found in any body tissue. Recent pre-clinical studies reveal that L-Rhamnose-based vaccines provide a protective effect by increasing IgG antibody titers without causing cross-reactive antibodies in test animal tissue. These findings demonstrate that the L-Rhamnose-based vaccine possesses strong immunogenicity, which effectively protects against GAS infection while maintaining a significantly higher degree of safety.

Stem cell seeding of decellularised porcine right ventricular outflow tracts to advance repair of congenital heart defects

Abstract Background Replacement of the right ventricular outflow tract (RVOT) is necessary in many critical congenital heart disease subtypes, often when the child is less than one year old. Poor availability of small-diameter cardiac homografts necessitates the use of xenografts in paediatric surgical reconstruction. Currently used xenografts are limited by immunoincompatibility and lack of growth, requiring repeat surgery to replace the defective graft. One approach to tackle acute immune rejection of animal tissue is aldehyde fixation of grafts prior to xenotransplantation. Though masking antigenicity, fixation is associated with multiple issues, including toxicity of fixative remnants and calcification. Decellularisation of biological grafts to remove foreign material is a promising alternative to reduce immunogenicity and dampen the risk of rejection. To combat lack of growth, in vitro cellularisation with stem cells is a promising solution. Purpose Current RVOT substitutes have not proven to be a lifelong solution for paediatric cardiac repair. This research has optimised a novel decellularisation technique for porcine RVOTs to produce a durable and cell-free scaffold with translational capability. Current work is looking to seed mesenchymal stem cells (MSCs) onto the acellular RVOT in vitro to enhance immune tolerance and endow the graft with growth capacity upon implant. Methods First, this decellularisation technique produces acellular RVOT scaffolds by simultaneously utilising three methods: enzymatic, chemical, and mechanical decellularisation. Novel to this method, the latter is realised using a 3D printed flow chamber to utilise the shear forces of continuous fluid flow for cell removal from the external and internal RVOTs structure. Coating the acellular graft with poly-lysine has then enabled recellularisation with MSCs isolated from the umbilical cord. Results Nuclei quantification demonstrates decellularisation of all structures of the RVOT, and elimination of residual nucleic acids is evidenced. Immunohistochemical analysis confirms the xenoantigen Galα1-3Galβ1-4GlcNAc-R is absent from the decellularised tissue. In parallel with removal of typical immunogens associated with the rejection response, the elastin and collagen fibres of the extracellular matrix are maintained, supported by histology and electron microscopy. Importantly, the tensile properties of the decellularised grafts are preserved. Finally, MSCs adhered onto the external pulmonary artery surface in vitro, achieving a uniform monolayer of cells. Conclusion RVOTs have been successfully decellularised and proven to possess seeding potential. Future work aims to characterise the seeded MSCs to assess parameters including proliferative capacity and expression of typical MSC markers. Overall, this work has the potential to produce a non-immunogenic graft possessing growth potential as a surgical alternative for paediatric RVOT replacement.

Biogenic and risk elements in wild boar testes and relation to spermatozoa motility

Environmental pollution results in serious health hazards to animals, reflected in biogenic and risk element concentrations in animal tissues. The objective of this study was to examinate concentration of selected elements in testes, and epididymal spermatozoa motility of wild boars. Wild boars were hunted in region Žuhračka - Levice, Slovak Republic. Testes were removed postmortem, spermatozoa were collected from cauda epididymis and assessed by CASA system. Elements concentrations were measured by ICP and by CV-AAS. Spermatozoa motility was 44.29% and progressive motility 18.47%. Concentration of elements in testes was in following order: K > Na > Mg > Ca > Fe > Zn > Al > Cu > Se > Mn > As > Cr > Pb > Mo > Sr > Ni > Ba > Cd > Li > Hg. The most notable correlations indicate association between Se and total spermatozoa motility, as well as with progressive motility, furthermore between As and velocity curved line and beat cross frequency. A high positive significant correlation was found between mercury and beat cross frequency. The data may serve as a fine control indicator to detect potentially toxic elements accumulated from polluted environment that can affect reproduction of wild animals.

Vitamin C improved anxiety and depression like behavior induced by chronic unpredictable mild stress in adolescent rats by influencing on oxidative stress balance, neurotransmitter systems, and inflammatory response

ABSTRACT Objectives: Stress is an adaptive response to different events in daily life that could strain physically, emotionally, or psychologically. Adolescence is an important developmental period due to physical, psychological, and social maturation. The aim of our study is to state whether chronic unpredictable mild stress (CUMS) during adolescence in male rats can cause anxiety and depression in adulthood and whether vitamin C (Vit C) can prevent this problem or not. Methods: For this purpose, we performed behavioral tests, including open field test, elevated plus maze, and forced swimming test. In addition, we investigated the metabolism of serotonin, the level of inflammation, oxidative stress and brain-derived neurotrophic factor (BDNF) in the brain cortex tissue of animals. Results: Results indicated that CUMS exacerbates mood-related behaviors by affecting the brain oxidative stress balance, inflammatory response, and serotonin metabolism. Moreover, we found that CUMS-Vit C co-treatment could significantly reverse CUMS-induced complications by restoration of the mentioned biochemical parameters. Discussion: Taken together, we would like to suggest the use of Vit C supplementation as a safe, inexpensive, and effective strategy for the management of CUMS.

Evaluation of fenugreek (Trigonella foenum-graecum L.) powder supplementation on metabolic syndrome, oxidative stress and inflammation in high fat diet fed rats

As an anti-diabetic medicinal plant, fenugreek seed (FG) (Trigonella foenum-graecum L.) has long been utilized and has many therapeutic uses. The current investigation sought to ascertain the effects of FG powder supplementation on insulin resistance, dyslipidemia, and oxidative stress in rats given a high-fat (HF) diet. Measurements of biochemical and antioxidant indicators were made in animal blood and tissue samples, including malondialdehyde (MDA), nitric oxide (NO), advanced oxidation protein product (AOPP), reduced glutathione (GSH), superoxide dismutase (SOD), triglycerides (TG), and catalase (CAT). Furthermore, the tissues of the kidney, heart, and liver were stained histologically. HF diet feeding in rats declined in antioxidant enzyme activities, along with a rise in MDA and other indicators of oxidative stress, which were mitigated by the supplementation of FG. Additionally, FG supplementation enhanced the expression of genes corresponding to antioxidants in the liver of rats given HF diet. FG supplements in HF diet-fed rats displayed altered gene expression in the livers that metabolized fat. Histological staining of the liver demonstrated that FG supplementation reduced necrosis and the accumulation of fat droplets in the liver of rats given HF diets. In conclusion, this finding showed that FG supplementation in HF diet fed rats reduced the plasma lipids, decreased oxidative stress and raised antioxidant enzyme activities. FG may therefore aid in reducing the chronic complications linked to the HF diet in experimental rats.

Extraction and Purification of Melanin from Different Sources and Tissues

Melanins are phenolic biopolymers synthesized by most of the living organism mainly for photoprotection or surviving in harsh conditions. Melanin is localized in different areas or complexed with different other biomolecules when observed from animals to microbes. This makes the melanin extraction procedure different in animal, plant and microbial tissues. Basically, the alkali- acid extraction is used in most protocols of which slight variations are there depending on the tissue used. This review will try to compile melanin extraction procedures from different cells and tissues ranging from animals to bacteria.

Simultaneous determination of macrolide and quinolone antibiotics in animal tissues for human consumption validated by Regulation (EU) 2021/808

In this work, an analytical method for the simultaneous detection and quantification of 11 macrolides (erythromycin A, gamithromycin, lincomycin, neospiramycin, pirlimycin, spiramycin, tildipirosin, tilmicosin, tulathromycin A and its metabolite CP-60300, and tylosin A) and 10 quinolones (ciprofloxacin, danofloxacin, difloxacin, enrofloxacin, flumequine, marbofloxacin, nalidixic acid, norfloxacin, oxolinic acid, and sarafloxacin) in muscle (bovine, ovine, porcine, equine, rabbit, poultry including laying hens, and fish) and kidney (bovine, ovine, porcine, equine) for human consumption was developed and validated according to Commission Implementing Regulation (EU) 2021/808. Sample preparation consisted of liquid extraction using a citrate–phosphate/EDTA buffer solution (McIlvaine buffer) followed by solid phase extraction for cleanup and UHPLC-MS/MS analysis. The developed method was comprehensively validated with regard to relative matrix effects (CVMF ≤ 20 %), linearity (R2 ≥ 0.98), accuracy (84–119 %), trueness (−16 to + 19 %), repeatability (2.1–20.0 %), reproducibility (3.0–25.0 %), selectivity, and robustness. The method limit of quantification values ranged from 2 to 40 µg kg−1, established as 0.1 × the lowest maximum residue limit (MRL) by species for the authorized antibiotics. Method applicability was demonstrated in six interlaboratory proficiency tests, and in the official control analyses of 1200 field samples of muscle and kidney.

Pharmacokinetics of the drug Amoxyantar in pigs

The article presents the results of pharmacokinetic studies of the drug Amoxiyantar in pigs. The results obtained indicate that amoxicillin is distributed throughout the tissues of animals, providing therapeutic concentrations in the studied dosage, ensuring effective distribution in the organs and tissues of the body of pigs, and also confirm the bioavailability of succinic acid with a high concentration in the blood plasma for an average of two hours. Based on the results of determining the dynamics of excretion of residual amounts of amoxicillin, it was detected in only one animal in the kidneys at a concentration of 54.9 μg/kg and in muscle tissue at a concentration of 25.2 μg/kg. In the remaining tissue samples of pigs obtained two days after application of the drug, as well as in all tissue samples of pigs obtained from the sixth day to the 18th day after application of the drug, amoxicillin was not detected.

PKD2: An Important Membrane Protein in Organ Development.

PKD2 was first identified as the pathogenic protein for autosomal dominant polycystic kidney disease (ADPKD) and is widely recognized as an ion channel. Subsequent studies have shown that PKD2 is widely expressed in various animal tissues and plays a crucial role in tissue and organ development. Additionally, PKD2 is conserved from single-celled organisms to vertebrates. Here, we provide an overview of recent advances in the function of PKD2 in key model animals, focusing on the establishment of left-right organ asymmetry, renal homeostasis, cardiovascular development, and signal transduction in reproduction and mating. We specifically focus on the roles of PKD2 in development and highlight future prospects for PKD2 research.