Yeast peptides alleviate lipopolysaccharide-induced intestinal barrier damage in rabbits involving Toll-like receptor signaling pathway modulation and gut microbiota regulation.

Introduction: Yeast peptides have garnered attention as valuable nutritional modifiers due to their potential health benefits. However, the precise mechanisms underlying their effects remain elusive. This study aims to explore the potential of yeast peptides, when added to diets, to mitigate lipopolysaccharide (LPS)-induced intestinal damage and microbiota alterations in rabbits. Methods: A total of 160 35-day-old Hyla line rabbits (0.96 ± 0.06 kg) were randomly assigned to 4 groups. These groups constituted a 2 × 2 factorial arrangement: basal diet (CON), 100 mg/kg yeast peptide diet (YP), LPS challenge + basal diet (LPS), LPS challenge +100 mg/kg yeast peptide diet (L-YP). The experiment spanned 35 days, encompassing a 7-day pre-feeding period and a 28-day formal trial. Results: The results indicated that yeast peptides mitigated the intestinal barrier damage induced by LPS, as evidenced by a significant reduction in serum Diamine oxidase and D-lactic acid levels in rabbits in the L-YP group compared to the LPS group (p < 0.05). Furthermore, in the jejunum, the L-YP group exhibited a significantly higher villus height compared to the LPS group (p < 0.05). In comparison to the LPS group, the L-YP rabbits significantly upregulated the expression of Claudin-1, Occludin-1 and ZO-1 in the jejunum (p < 0.05). Compared with the CON group, the YP group significantly reduced the levels of rabbit jejunal inflammatory cytokines (TNF-α, IL-1ß and IL-6) and decreased the relative mRNA expression of jejunal signaling pathway-associated inflammatory factors such as TLR4, MyD88, NF-κB and IL-1ß (p < 0.05). Additionally, notable changes in the hindgut also included the concentration of short-chain fatty acids (SCFA) of the YP group was significantly higher than that of the CON group (p < 0.05). 16S RNA sequencing revealed a substantial impact of yeast peptides on the composition of the cecal microbiota. Correlation analyses indicated potential associations of specific gut microbiota with jejunal inflammatory factors, tight junction proteins, and SCFA. Conclusion: In conclusion, yeast peptides have shown promise in mitigating LPS-induced intestinal barrier damage in rabbits through their anti-inflammatory effects, modulation of the gut microbiota, and maintenance of intestinal tight junctions.

Use of subcutaneous maropitant at two dosages for pain management in domestic rabbits (Oryctolagus cuniculus) undergoing elective ovariohysterectomy or orchiectomy.

OBJECTIVE: To describe the effect of two doses of maropitant on pain scores, food intake, and fecal output in domestic rabbits (Oryctolagus cuniculus) undergoing elective ovariohysterectomy or orchiectomy. ANIMALS: 26 (11 female, 15 male) rabbits from three institutions. PROCEDURES: Rabbits were randomly assigned to one of three treatment groups: low-dose maropitant (LDM; 2 mg/kg SC once; n=8), moderate-dose maropitant (MDM; 4 mg/kg SC once; n=10), and control (saline equivalent to 4 mg/kg maropitant SC once; n=8), administered prior to surgery. Following surgery, all rabbits were provided buprenorphine (0.06 mg/kg q 8 hours) and meloxicam (1 mg/kg q 24 hours) intramuscularly. Rabbits were monitored using video surveillance postoperatively until 24 hours after surgery or discharge from the hospital, whichever came first. Pain scores were assessed by three blinded observers, and results were grouped into early (0-4 hours), mid (5-8 hours), and late (12-24 hours) time frames. Food intake and fecal output were compared between groups. Statistical analysis was performed using Chi square, Fisher's exact tests, and a mixed model approach. RESULTS: There were no adverse effects with maropitant administration. Rabbits that received MDM had significantly lower pain scores in the mid-time frame and behavior scores in the late-time frame compared to controls. Male rabbits consumed more food than females and rabbits hospitalized longer than 12 hours consumed more food than those that were discharged prior. No significant differences were detected in facial grimace scale scores, food intake, or fecal production among treatment groups. CONCLUSIONS AND CLINICAL RELEVANCE: Moderate dose maropitant decreased pain related behaviors in the mid-time frame and behavior scores in the late-time frame after surgery. Further studies are necessary to better characterize the potential use of maropitant in postoperative analgesia.

The first report of single nucleotide polymorphisms in the open reading frame of the prion-like protein gene in rabbits.

Background: Natural cases of prion disease have not been reported in rabbits, and prior attempts to identify a prion conversion agent have been unsuccessful. However, recent applications of prion seed amplifying experimental techniques have sparked renewed interest in the potential susceptibility of rabbits to prion disease infections. Among several factors related to prion disease, polymorphisms within the prion-like protein gene (PRND), a member of the prion protein family, have been reported as significantly associated with disease susceptibility in various species. Therefore, our study aimed to investigate polymorphisms in the PRND gene of rabbits and analyze their genetic characteristics. Methods: Genomic DNA was extracted from 207 rabbit samples to investigate leporine PRND polymorphisms. Subsequently, amplicon sequencing targeting the coding region of the leporine PRND gene was conducted. Additionally, linkage disequilibrium (LD) analysis was employed to assess the connection within and between loci. The impact of non-synonymous single nucleotide polymorphisms (SNPs) on the Doppel protein was evaluated using PolyPhen-2. Results: We found nine novel SNPs in the leporine PRND gene: c.18A > G, c.76G > C, c.128C > T, c.146C > T, c.315A > G, c.488G > A, c.525G > C, c.544G > A, and c.579A > G. Notably, seven of these PRND SNPs, excluding c.525G > C and c.579A > G, exhibited strong LD values exceeding 0.3. In addition, LD analysis confirmed a robust link between PRNP SNP c.234C > T and PRND SNPs at c.525G > C and c.579A > G. Furthermore, according to PolyPhen-2 and SIFT analyses, the four non-synonymous SNPs were predicted to have deleterious effects on the function or structure of the Doppel protein. However, PANTHER and Missense3D did not indicate such effects. Conclusion: In this paper, we have identified novel SNPs in the rabbit PRND gene and predicted their potential detrimental effects on protein function or structure through four non-synonymous SNPs. Additionally, we observed a genetic linkage between SNPs in the PRND and PRNP genes. These findings may provide insights into understanding the characteristics of rabbits as partially resistant species. To the best of our knowledge, this study is the first to genetically characterize PRND SNPs in rabbits.

Conformation-associated health in pet rabbits in the UK: A VetCompass cohort study.

BACKGROUND: Domestic rabbit breeds vary substantially from the wild rabbit body type. However, little is known about how the conformation of pet rabbits influences their health. METHODS: Data were extracted from VetCompass anonymised clinical records of rabbits under UK primary veterinary care during 2019. RESULTS: The study included 162,107 rabbits. Based on 88,693 rabbits with relevant breed information recorded, skull shape was classified as brachycephalic (79.69%), mesaticephalic (16.80%) and dolichocephalic (3.51%). Based on 83,821 rabbits with relevant breed information recorded, ear carriage was classified as lop-eared (57.05%) and erect-eared (42.95%). From a random sample of 3933 rabbits, the most prevalent disorders recorded overall were overgrown nail(s) (28.19%), overgrown molar(s) (14.90%) and obesity (8.82%). Compared to those with a mesaticephalic skull shape, brachycephalic rabbits had lower odds of obesity, anorexia and gastrointestinal stasis and higher odds of perineal faecal impaction, tear duct abnormality and haircoat disorder. Compared to erect-eared rabbits, lop-eared rabbits had higher odds of perineal faecal impaction and tear duct abnormality. LIMITATION: A large proportion of records with incomplete breed information hindered full analysis for breed-related and conformation-related attributes. CONCLUSION: Limited evidence for major links between skull shape or ear carriage conformations and overall disorder risk suggests that factors such as husbandry or even just living life as a domesticated species may be bigger drivers of common health issues in pet rabbits in the UK.

Mechanical loading on cell-free polymer composite scaffold enhances in situ regeneration of fully functional Achilles tendon in a rabbit model.

Traditional tendon engineering using cell-loaded scaffold has limited application potential due to the need of autologous cells. We hypothesize that potent mechanical loading can efficiently induce in situ Achilles tendon regeneration in a rabbit model by using a cell-free porous composite scaffold. In this study, melt-spinning was used to fabricate PGA (polyglycolic acid) and PLA (polylactic acid) filament fibers as well as non-woven PGA fibers. The PLA/PGA (4:2) filament fibers were further braided into a hybrid yarn，which was knitted into a PLA/PGA tubular mesh with potent mechanical property for sustaining natural tendon strain. The results showed that a complete cross-section of Achilles tendon created a model of full mechanical loading on the bridging scaffold, which could efficiently induce in situ tendon regeneration by promoting host cell infiltration, matrix production and tissue remodeling. Histologically, mechanical loading assisted in forming parallel aligned collagen fibers and tenocytes in a fashion similar to those of native tendon. Transmission electron microscope further demonstrated that mechanical strain induced collagen fibril development by increasing fibril diameter and forming bipolar structure, which resulted in enhanced mechanical properties. Interestingly, the synergistic effect between mechanical loading and hyaluronic acid modification was also observed on the induced tenogenic differentiation of infiltrated host fibroblasts. In conclusion, potent mechanical loading is the key inductive microenvironment for in situ tendon regeneration for this polymer-based composite scaffold with proper matrix modification, which may serve as a universal scaffold product for tendon regeneration.

Rhabdomyosarcoma in a Rabbit.

A geriatric Holland Lop rabbit presented for acute lameness. A pathologic fracture of the right distal femur associated with a pleomorphic rhabdomyosarcoma was diagnosed, and staging radiographs showed no overt metastasis upon initial presentation. The limb was amputated and submitted for microscopic examination. Immunohistochemical evaluation revealed the neoplastic cells were positive for desmin and MyoD1, and negative for cytokeratin AE1/AE3, CD204, IBA-1, and SMA. Gross, histologic, and immunohistochemical evaluation confirmed a diagnosis of pleomorphic rhabdomyosarcoma. The patient died 396 days after amputation, and a post-mortem examination showed metastatic sarcoma to multiple organs.

Marine macroalgae in rabbit feed - Effects on meat quality.

The addition of macroalgae to livestock diets has demonstrated to enhance the quality of meat by improving the muscle stability, antioxidant capacity and fatty acid profile. However, information regarding rabbit meat is scarce. This study evaluated the effect of adding 1.025% of different macroalgae, dehydrated and as extracts (Saccharina latissima, Himanthalia elongata and Ulva spp.) to the diet of growing rabbits. Dietary supplementation with the Ulva spp. extract increased the fat content (0.96% vs 0.33% in control group) and the proportion of monounsaturated fatty acids (by 22%; P ≤ 0.022), but did not affect the moisture, protein or ash contents or the physicochemical properties of the rabbit longissiumus lumborum muscle. The antioxidant status of the meat was adequate and was not affected by the dietary supplements. The sensorial properties of the meat were also not affected, and dietary supplementation with both S. latissima and H. elongata actually enhanced the flavour and juiciness of the meat (P ≤ 0.01). Altogether, the study findings indicate that the addition of these sustainable ingredients to rabbit feed did not negatively affect meat quality, and some of them may potentially improve specific characteristics, which could make this meat more attractive to consumers.

Spontaneous histopathology in New Zealand White rabbits: ten years of control data.

The historical control database of a multinational laboratory services provider was queried for all histopathologic findings in New Zealand White rabbits which were used as control animals during a ten-year period (2011-2020). The query included all evaluated tissues, with or without microscopic findings, in studies conducted for safety testing for regulatory approval by the U.S. Food and Drug Agency (FDA) or the U.S. Environmental Protection Agency. A second query included studies conducted in the United Kingdom for control rabbits used in studies compliant with the Healthcare Products Regulatory Agency (MHRA) and/or the European Medicines Agency (EMA), which provide regulatory oversight in the United Kingdom and European Union, respectively. Infiltrates of inflammatory (mixed or mononuclear) cells were commonly noted in various organs including heart, digestive tract, muscle, thyroid, kidney, urinary bladder, eyelid, ocular structures, harderian gland, lacrimal gland, and lung. Mineralization was noted in aorta, kidney, urinary bladder, and ovary. Also noted were degeneration/necrosis in the myocardium, and intramuscular injection sites of the skin, degeneration/regeneration of muscle and diaphragm, ectopic tissue in the pancreas and thyroid, basophilic foci in salivary gland, increased/decreased vacuolation in adrenal gland, increased/decreased lymphocytic cellularity of lymph nodes, intrasinusoidal erythrocytes in lymph nodes, thymic atrophy, increased adipocytes in bone marrow, inflammatory cell foci in the liver and gall bladder, lacrimal gland atrophy, renal tubule basophilia, degeneration/regeneration, and dilatation; oviduct cyst; in the testis, degeneration/atrophy, cellular debris, dilatation, decreased sperm and segmental hypoplasia of seminiferous tubules; and squamous metaplasia of the testis and seminal vesicle.

Belimumab concentration measurements using a homologous anti-idiotype immunoassay.

Monitoring belimumab concentrations in patients can be a valuable tool for assessing treatment response and for personalizing drug doses. Various assay formats may be used to measure concentrations of therapeutic monoclonal antibodies. A particularly useful format involves the use of anti-idiotype monoclonal antibodies, selected to be highly specific to the antibody of interest. Here, we describe the development of a specific, high-affinity anti-idiotype antibody to belimumab, and the application of this antibody in a homologous sandwich ELISA to measure belimumab concentrations.

Effect of dietary supplementation of macadamia oil on the growth, immune function, physio-biochemical components and thyroid activity of growing rabbits.

The current research aimed to assess the effects of dietary macadamia oil (MO) on carcass traits, growth performance, physio-biochemical components, immune function, thyroid hormones and inflammation markers of growing rabbits. A total of 96 growing rabbits were randomly distributed into four treatments, with 24 rabbits in each group. The rabbits were fed a basal diet (control group) or a diet supplemented with MO at 0.5 (MO0.5), 1 (MO1.0) and 2 (MO2.0) mL/kg of diet for eight weeks. The daily body weight gain and feed conversion ratio showed a quadratic improvement with increasing levels of MO, and the optimal dose was 1.25 mL/kg of diet. Increasing levels of MO also had a quadratic effect on hepatic and renal functions. Dose-response curves revealed that the optimal doses of MO were 1.50, 1.75 and 1.25 mL/kg of diet for total bilirubin, gamma-glutamyl transferase, and creatinine respectively. A quadratic relationship was observed between the increased levels of MO and tumour necrosis factor-α (p = 0.038), interleukin-6 (p = 0.014) and immunoglobulins (p = 0.016 and IgM p = 0.026). Additionally, a linear relationship was observed between the increment in MO levels and both nitric oxide (p = 0.040) and interleukin-4 (p = 0.001). The activities of superoxide dismutase and glutathione peroxidase showed a linear increase with increasing dietary MO content, while xanthine oxidase showed a linear decrease. Total antioxidant capacity showed quadratic improvement (p = 0.035) with the dietary treatment, with the optimal dose observed at 1.25 mL/kg of diet. The inclusion of MO in the diet had a linear effect on the activity of thyroxine (p = 0.001). Therefore, supplementation of MO at a dose of 1 or 1.5 mL/kg of diet in growing rabbits' diets can improve growth and carcass traits, sustain thyroid function by supporting immunity, and reduce oxidative/inflammation pathways.

Comprehensive analysis of key host gene-microbe networks in the cecum tissues of the obese rabbits induced by a high-fat diet.

The Cecum is a key site for cellulose digestion in nutrient metabolism of intestine, but its mechanisms of microbial and gene interactions has not been fully elucidated during pathogenesis of obesity. Therefore, the cecum tissues of the New Zealand rabbits and their contents between the high-fat diet-induced group (Ob) and control group (Co) were collected and analyzed using multi-omics. The metagenomic analysis indicated that the relative abundances of Corallococcus_sp._CAG:1435 and Flavobacteriales bacterium species were significantly lower, while those of Akkermansia glycaniphila, Clostridium_sp._CAG:793, Mycoplasma_sp._CAG:776, Mycoplasma_sp._CAG:472, Clostridium_sp._CAG:609, Akkermansia_sp._KLE1605, Clostridium_sp._CAG:508, and Firmicutes_bacterium_CAG:460 species were significantly higher in the Ob as compared to those in Co. Transcriptomic sequencing results showed that the differentially upregulated genes were mainly enriched in pathways, including calcium signaling pathway, PI3K-Akt signaling pathway, and Wnt signaling pathway, while the differentially downregulated genes were mainly enriched in pathways of NF-kappaB signaling pathway and T cell receptor signaling pathway. The comparative analysis of metabolites showed that the glycine, serine, and threonine metabolism and cysteine and methionine metabolism were the important metabolic pathways between the two groups. The combined analysis showed that CAMK1, IGFBP6, and IGFBP4 genes were highly correlated with Clostridium_sp._CAG:793, and Akkermansia_glycaniphila species. Thus, the preliminary study elucidated the microbial and gene interactions in cecum of obese rabbit and provided a basis for further studies in intestinal intervention for human obesity.

Expression and characterization of scFv-6009FV in Pichia pastoris with improved ability to neutralize the neurotoxin Cn2 from Centruroides noxius.

Small single-chain variable fragments (scFv) are promising biomolecules to inhibit and neutralize toxins and to act as antivenoms. In this work, we aimed to produce a functional scFv-6009FV in the yeast Pichia pastoris, which inhibits the pure Cn2 neurotoxin and the whole venom of Centruroides noxius. We were able to achieve yields of up to 31.6 ± 2 mg/L in flasks. Furthermore, the protein showed a structure of 6.1 % α-helix, 49.1 % ß-sheet, and 44.8 % of random coil by CD. Mass spectrometry confirmed the amino acid sequence and showed no glycosylation profile for this molecule. Purified scFv-6009FV allowed us to develop anti-scFvs in rabbits, which were then used in affinity columns to purify other scFvs. Determination of its half-maximal inhibitory concentration value (IC50) was 40 % better than the scFvs produced by E. coli as a control. Finally, we found that scFv-6009FV was able to inhibit ex vivo the pure Cn2 toxin and the whole venom from C. noxius in murine rescue experiments. These results demonstrated that under the conditions assayed here, P. pastoris is suited to produce scFv-6009FV that, compared to scFvs produced by E. coli, maintains the characteristics of an antibody and neutralizes the Cn2 toxin more effectively.

Glucocorticoids disrupt longitudinal advance of cortical bone basic multicellular units in the rabbit distal tibia.

Glucocorticoids (GCs) are the leading cause of secondary osteoporosis. The emerging perspective, derived primarily from 2D histological study of trabecular bone, is that GC-induced bone loss arises through the uncoupling of bone formation and resorption at the level of the basic multicellular units (BMUs), which carry out bone remodeling. Here we explore the impact of GCs on cortical bone remodeling in the rabbit model. Based upon the rapid reduction of bone formation and initial elevation of resorption caused by GCs, we hypothesized that the rate of advance (longitudinal erosion rate; LER) of cortical BMUs would be increased. To test this hypothesis we divided 20 female New Zealand White rabbits into four experimental groups: ovariohysterectomy (OVH), glucocorticoid (GC), OVH + GC and SHAM controls (n = 5 animals each). Ten weeks post-surgery (OVH or sham), and two weeks after the initiation of dosing (daily subcutaneous injections of 1.5 mg/kg of methylprednisolone sodium succinate in the GC-treated groups and 1 ml of saline for the others), the right tibiae were scanned in vivo using Synchrotron Radiation (SR) in-line phase contrast micro-CT at the Canadian Light Source. After an additional 2 weeks of dosing, the rabbits were euthanized and ex vivo images were collected using desktop micro-CT. The datasets were co-registered in 3D and LER was calculated as the distance traversed by BMU cutting-cones in the 14-day interval between scans. Counter to our hypothesis, LER was greatly reduced in GC-treated rabbits. Mean LER was lower in GC (4.27 µm/d; p < 0.001) and OVH + GC (4.19 µm/d; p < 0.001), while similar in OVH (40.13 µm/d; p = 0.990), compared to SHAM (40.44 µm/d). This approximately 90 % reduction in LER with GCs was also associated with an overall disruption of BMU progression, with radial expansion of the remodeling space occurring in all directions. This unexpected outcome suggests that GCs do not simply uncouple formation and resorption within cortical BMUs and highlights the value of the time-lapsed 4D approach employed.

Preliminary study of cyclosporine A/Lifitegrast subconjunctival sustained-release drug membrane in the treatment of dry eyes.

BACKGROUND: Dry eyes can cause discomfort. To treat dry eye disease, cyclosporine A (CsA) and Lifitegrast are two eye drugs approved by the U.S. Food and Drug Administration (FDA). However, frequent use of eye drops can be challenging and lead to poor compliance, especially in elderly patients. Therefore, this study aimed to develop a drug sustained-release vector and explore its therapeutic effect in animal models of dry eye. METHODS: Firstly, drug membranes loaded with both CsA and Lifitegrast using a carrier called poly(lactate-co-ε-caprolactone) (P(LLA-CL)) were prepared and evaluated for their physicochemical properties, release behavior in vitro, and safety in vivo. Next, a rabbit dry eye model using a 0.1% benzalkonium chloride (BAC) solution was developed and treated by drug-loaded micro membranes. We observed and recorded conjunctival hyperemia, corneal staining, corneal edema, corneal neovascularization, conjunctival goblet cells and hematoxylin and eosin (H&E) staining. Finally, we detected the MUC5AC and MMP-9 by immunofluorescence staining and enzyme-linked immunosorbent assay (ELISA). RESULTS: The composite film released both CsA and Lifitegrast for at least one month. Compared to the blank membrane group, conjunctival hyperemia, corneal fluorescein staining, corneal edema, corneal neovascularization and conjunctival goblet cells recovered faster in the drug membrane group, and the difference was statistically significant. At the molecular level, the drug membrane group showed an increase in mucin density and a significant anti-inflammatory effect. CONCLUSIONS: The implantation of CsA/Lifitegrast loaded P(LLA-CL) membrane under the subconjunctival of the rabbit eye is safe. The study suggests that this subconjunctival administration could be developed into a minimally invasive delivery system to help patients with dry eye disease who require multiple daily eyedrops but have poor compliance.

Optimization of immunosuppression strategies for the establishment of chronic hepatitis E virus infection in rabbits.

Chronic hepatitis E mostly occurs in organ transplant recipients and can lead to rapid liver fibrosis and cirrhosis. Previous studies found that the development of chronic hepatitis E virus (HEV) infection is linked to the type of immunosuppressant used. Animal models are crucial for the study of pathogenesis of chronic hepatitis E. We previously established a stable chronic HEV infection rabbit model using cyclosporine A (CsA), a calcineurin inhibitor (CNI)-based immunosuppressant. However, the immunosuppression strategy and timing may be optimized, and how different types of immunosuppressants affect the establishment of chronic HEV infection in this model is still unknown. Here, we showed that chronic HEV infection can be established in 100% of rabbits when CsA treatment was started at HEV challenge or even 4 weeks after. Tacrolimus or prednisolone treatment alone also contributed to chronic HEV infection, resulting in 100% and 77.8% chronicity rates, respectively, while mycophenolate mofetil (MMF) only led to a 28.6% chronicity rate. Chronic HEV infection was accompanied with a persistent activation of innate immune response evidenced by transcriptome analysis. The suppressed adaptive immune response evidenced by low expression of genes related to cytotoxicity (like perforin and FasL) and low anti-HEV seroconversion rates may play important roles in causing chronic HEV infection. By analyzing HEV antigen concentrations with different infection outcomes, we also found that HEV antigen levels could indicate chronic HEV infection development. This study optimized the immunosuppression strategies for establishing chronic HEV infection in rabbits and highlighted the potential association between the development of chronic HEV infection and immunosuppressants.IMPORTANCEOrgan transplant recipients are at high risk of chronic hepatitis E and generally receive a CNI-based immunosuppression regimen containing CNI (tacrolimus or CsA), MMF, and/or corticosteroids. Previously, we established stable chronic HEV infection in a rabbit model by using CsA before HEV challenge. In this study, we further optimized the immunosuppression strategies for establishing chronic HEV infection in rabbits. Chronic HEV infection can also be established when CsA treatment was started at the same time or even 4 weeks after HEV challenge, clearly indicating the risk of progression to chronic infection under these circumstances and the necessity of HEV screening for both the recipient and the donor preoperatively. CsA, tacrolimus, or prednisolone instead of MMF significantly contributed to chronic HEV infection. HEV antigen in acute infection phase indicates the development of chronic infection. Our results have important implications for understanding the potential association between chronic HEV infection and immunosuppressants.

Promotion and Mechanism of Acupotomy on Chondrocyte Autophagy in Knee Osteoarthritis Rabbits.

OBJECTIVE: To explore the effect of acupotomy intervention on autophagy of chondrocytes in rabbits with knee osteoarthritis (KOA), and to determine the possible mechanisms of acupotomy to alleviate cartilage degeneration. METHODS: The modified Videman method was used to construct a KOA rabbit model. After modeling, 40 rabbits were randomly divided into 4 groups by a random number table: control; KOA (model); KOA + acupotomy (acupotomy), and KOA + sham acupotomy (sham), 10 in each group. After a 3-week treatment course, the knee joint activity was determined by the modified Lequesne MG index. Hematoxylin-eosin staining staining was used to examine the morphological changes of chondrocytes. Autophagy of chondrocytes was observed by transmission electron microscopy. The surface morphology of cartilage tissue was observed by scanning electron microscope. The mRNA and protein levels of AMP kinase/mammalian target of rapamycin/Unc-51 (AMPK/mTOR/ULK1) signal pathway key proteins, autophagy-related factor Beclin-1 and microtubule-associated protein 1A/1B light chain 3 (LC3) in rabbit knee cartilage were assessed by real-time fluorescence quantitative polymerase chain reaction and Western blot, respectively. RESULTS: The modified Lequesne MG score of acupotomy group was significantly lower than that of model group (P<0.05). Pathological results showed that chondrocyte autophagy decreased and cartilage surface was rough in the model group, which recovered after acupotomy treatment. The mRNA expressions of AMPK, ULK1, Beclin-1 and the protein levels of p-AMPK, p-ULK1, Beclin-1, and LC3 II/LC3 I were decreased in the model group, while the mRNA and protein expressions of mTOR were increased (P<0.01). However, acupotomy treatment reversed these abnormal changes (P<0.05). CONCLUSIONS: Acupotomy could effectively up-regulate the expressions of AMPK, ULK1 and Beclin1, reduce the expression of mTOR, promote autophagy, and alleviate joint degeneration. Acupotomy is a promising complementary and alternative therapy for KOA.

Establishment of a rabbit model of different degrees of testicular torsion.

INTRODUCTION AND OBJECTIVES: Different degrees of testicular torsion result in varying degrees of testicular damage, which influences treatment options and outcomes. Therefore, establishing a testicular torsion model with different degrees is necessary for clinical diagnosis. MATERIALS AND METHODS: Rabbits were randomly divided into four groups and their spermatic cords were twisted at 0 °, 180 °, 360 °, and 720 °, respectively. Color Doppler flow imaging (CDFI) were performed to evaluate the blood supply in testicles. The twisted testicles were surgically removed at six hours post-operation and were evaluated by morphological observation and Hematoxylin and Eosin staining. RESULTS: CDFI signals were gradually decreased as the degree of testicular torsion increased, and scores of CDFI in the 360 ° and 720 ° groups were significantly decreased at postoperative six hours compared to pre-surgery. Compared to the sham, the testicle in the 180 ° group exhibited slight congestion, whereas the testicles in the 360 ° and 720 ° groups were dark red in color and had severe congestion and unrecognizable vessels. Hematoxylin and Eosin staining showed mild spermatogenic cell reduction and testicular interstitial hemorrhage in the 180 ° group. In the 360 ° and 720 ° groups, disordered seminiferous tubules, shed spermatogenic cells in tubules, inflammatory cell infiltration, and severe hemorrhage were found. In comparison with the sham, interstitial hemorrhage scores in the 360 ° and 720 ° groups were significantly higher, and scores of germinal epithelial cell thickness in the three testicular torsion groups were significantly decreased. CONCLUSIONS: Collectively, we successfully constructed a testicular torsion model with different degrees in rabbits.

Mammalian lures monitored with time-lapse cameras increase detection of pythons and other snakes.

Background: Enhancing detection of cryptic snakes is critical for the development of conservation and management strategies; yet, finding methods that provide adequate detection remains challenging. Issues with detecting snakes can be particularly problematic for some species, like the invasive Burmese python (Python bivittatus) in the Florida Everglades. Methods: Using multiple survey methods, we predicted that our ability to detect pythons, larger snakes and all other snakes would be enhanced with the use of live mammalian lures (domesticated rabbits; Oryctolagus cuniculus). Specifically, we used visual surveys, python detection dogs, and time-lapse game cameras to determine if domesticated rabbits were an effective lure. Results: Time-lapse game cameras detected almost 40 times more snakes (n = 375, treatment = 245, control = 130) than visual surveys (n = 10). We recorded 21 independent detections of pythons at treatment pens (with lures) and one detection at a control pen (without lures). In addition, we found larger snakes, and all other snakes were 165% and 74% more likely to be detected at treatment pens compared to control pens, respectively. Time-lapse cameras detected almost 40 times more snakes than visual surveys; we did not detect any pythons with python detection dogs. Conclusions: Our study presents compelling evidence that the detection of snakes is improved by coupling live mammalian lures with time-lapse game cameras. Although the identification of smaller snake species was limited, this was due to pixel resolution, which could be improved by changing the camera focal length. For larger snakes with individually distinctive patterns, this method could potentially be used to identify unique individuals and thus allow researchers to estimate population dynamics.

Rabbit muscle pyruvate kinase activators: Synthesis, molecular docking and theoretical studies of N-substituted sulfonamide derivatives.

Pyruvate kinase (PK) activators have potential therapeutic applications in diseases such as sickle cell anemia. In this study, N-Substituted sulfonamide derivatives of 1,4-dihydropyridines were synthesized and evaluated as PK activators in vitro and using molecular docking studies. The compounds were synthesized by reacting dicarbonyl compounds with ammonium acetate, 5-nitrobenzaldehyde, and alumina sulfuric acid (ASA), followed by reduction and sulfonylation. The structures of the compounds were analyzed using spectroscopic techniques. DFT calculations provided insights into the electronic properties. Molecular docking of the compounds into the active site of PK showed favorable binding interactions. ADME evaluation indicated suitable solubility, BBB permeation, and lack of CYP450 inhibition. Overall, this study demonstrates the potential of new hybrid 1,4-dihydropyridine substituted sulfonamides as PK activators for further development. According to AC50 values, the compound (DTSF7, 0.97µM) is about 100-fold higher affective than the clinically used sulfonamide compound (AC50 = 90µM) for PK.

In Vivo Imaging of Rabbit Follicles through Combining Ultrasound Bio-Microscopy and Intravital Window.

Continuous ovarian imaging has been proven to be a method for monitoring the development of follicles in vivo. The aim of this study was to evaluate the efficacy of combining ultrasound bio-microscopy (UBM) with an intravital window for follicle imaging in rabbits and to monitor the ovarian dynamic processes. New Zealand White female rabbits (n = 10) received ovarian translocation to a subcutaneous position. The ovarian tissue was sutured onto the abdominal muscles and covered with an intravital window for the continuous monitoring of the follicles using UBM. Results show that physiological changes (red blood cell and white blood cell counts, feed intake, and body weight change) in rabbits induced by surgery returned to normal physiological levels in one week. Furthermore, UBM could provide high-resolution imaging of follicles through the intravital window. Daily monitoring of ovarian dynamic processes for 6 days displayed variabilities in follicle counts and size. Collectively, these results provide a relatively new method to monitor ovarian dynamic processes and to understand the reproductive physiology of female rabbits.