Establishment of an Animal Model of Dog Bite Injuries.

Nowadays dog bite is becoming a world public health problem. Therefore, the study aimed to develop a dog bite animal model that is helpful to solve these problems. In this study, the skull of an adult dog was scanned. The three-dimensional model of the dog maxillofacial bones and dentition was built by MIMICS. Next, the model was printed with Co-Cr alloy by using selective laser sintering technology to develop the dog bite simulation pliers. Then, to simulate dog bite to most, the maximum bite force of the pliers was measured and actions contained in dog bite process was analyzed. Afterwards, according to action analysis results, rabbits were bitten by the prepared instrument in actions that simulate dog's bite. Finally, the reproducibility and controllability of this animal model of dog bite injuries was validated in an in vivo study. The results showed a reliable animal model of dog bite injuries has been developed in this study. The sites and severities of the injuries could be adjusted as the operator wishes and the animal model of dog bite injuries was highly repeatable. This study also indicates the feasibility of using digital technology in establishing animal bite models.

Extract from Aronia melanocarpa, Lonicera caerulea, and Vaccinium myrtillus Improves near Visual Acuity in People with Presbyopia.

Presbyopia is a global problem with an estimated 1.3 billion patients worldwide. In the area of functional food applications, dietary supplements or herbs, there are very few reports describing the positive effects of their use. In the available literature, there is a lack of studies in humans as well as on an animal model of extracts containing, simultaneously, compounds from the polyphenol group (in particular, anthocyanins) and iridoids, so we undertook a study of the effects of a preparation composed of these compounds on a condition of the organ of vision. Our previous experience on a rabbit model proved the positive effect of taking an oral extract of Cornus mas in stabilizing the intraocular pressure of the eye. The purpose of this study was to evaluate the effect of an orally administered ternary compound preparation on the status of physiological parameters of the ocular organ. The preparation contained an extract of the chokeberry Aronia melanocarpa, the honeysuckle berry Lonicera caerulea L., and the bilberry Vaccinium myrtillus (hereafter AKB) standardized for anthocyanins and iridoids, as bioactive compounds known from the literature. A randomized, double-blind, cross-over study lasting with a "wash-out" period of 17 weeks evaluated a group of 23 people over the age of 50, who were subjects with presbyopia and burdened by prolonged work in front of screen monitors. The group of volunteers was recruited from people who perform white-collar jobs on a daily basis. The effects of the test substances contained in the preparation on visual acuity for distance and near, sense of contrast for distance and near, intraocular pressure, and conjunctival lubrication, tested by Schirmer test, LIPCOF index and TBUT test, and visual field test were evaluated. Anthocyanins (including cyanidin 3-O-galactoside, delphinidin 3-O-arabinoside, cyanidin 3-O-glucoside, cyanidin 3-O-rutinoside, cyanidin 3-O-arabinoside) and iridoids (including loganin, sweroside, loganic acid) were identified as substances present in the extract obtained by HPLC-MS. The preliminary results showed that the composition of AKB applied orally does not change visual acuity in the first 6 weeks of administration. Only in the next cycle of the study was an improvement in near visual acuity observed in 92.3% of the patients. This may indicate potential to correct near vision in presbyopic patients. On the other hand, an improvement in conjunctival wetting was observed in the Schirmer test at the beginning of week 6 of administration in 80% of patients. This effect was weakened in subsequent weeks of conducting the experiment to 61.5%. The improvement in conjunctival hydration in the Schirmer test shows the potential beneficial effect of the AKB formulation in a group of patients with dry eye syndrome. This is the first study of a preparation based on natural, standardized extracts of chokeberry, honeysuckle berry, and bilberry. Preliminary studies show an improvement in near visual acuity and conjunctival hydration on the Schirmer test, but this needs to be confirmed in further studies.

[Clinical study of the efficacies of ruxolitinib plus low-dose PTCY for acute GVHD prevention after haploidentical transplantation in malignant hematological diseases].

Objective: To investigate and verify a novel acute graft versus host disease (aGVHD) prevention protocol in the context of haploidentical hematopoietic stem cell transplantation (haplo-HSCT) . Methods: Patients who underwent haplo-HSCT in our center between January 2022 and December 2022 were included. All patients received reduced doses of cyclophosphamide, Rabbit anti-human tymoglobulin, ruxolitinib, methotrexate, cyclosporine, and MMF to prevent aGVHD. The transplantation outcomes, complications, and survival rate of all patients were investigated. Results: A total of 52 patients with haplo-HSCT were enrolled, 29 (55.8%) male and 23 (44.2%) female, with a median age of 28 (5-59) years. There were 25 cases of acute myeloid leukemia, 17 cases of acute lymphocyte leukemia, 6 cases of myelodysplastic syndrome, 2 cases of chronic myeloid leukemia and 2 cases of myeloproliferative neoplasms. 98.1% of patients had successful engraftment. The incidence of Ⅱ-Ⅳ aGVHD and Ⅲ-Ⅳ aGVHD was 19.2% (95% CI 8.2% -30.3% ) and 7.7% (95% CI 0.2% -15.2% ), respectively. No patients experienced severe gastrointestinal mucositis. The Epstein-Barr virus and CMV reactivation rates were 40.4% and 21.3%, respectively. 9.6% of patients relapsed during followup, with 1-year overall survival, progression-free survival, and non-relapse mortality rates of 86.5% (95% CI 76.9% -96.1% ), 78.8% (95% CI 67.4% -90.3% ) and 11.5% (95% CI 2.6% -20.5% ), respectively. Conclusion: Ruxolitinib combined with a low dose of PTCY is a safe and effective first-line aGVHD prevention strategy.

CoPoP liposomes displaying stabilized clade C HIV-1 Env elicit tier 2 multiclade neutralization in rabbits.

One of the strategies towards an effective HIV-1 vaccine is to elicit broadly neutralizing antibody responses that target the high HIV-1 Env diversity. Here, we present an HIV-1 vaccine candidate that consists of cobalt porphyrin-phospholipid (CoPoP) liposomes decorated with repaired and stabilized clade C HIV-1 Env trimers in a prefusion conformation. These particles exhibit high HIV-1 Env trimer decoration, serum stability and bind broadly neutralizing antibodies. Three sequential immunizations of female rabbits with CoPoP liposomes displaying a different clade C HIV-1 gp140 trimer at each dosing generate high HIV-1 Env-specific antibody responses. Additionally, serum neutralization is detectable against 18 of 20 multiclade tier 2 HIV-1 strains. Furthermore, the peak antibody titers induced by CoPoP liposomes can be recalled by subsequent heterologous immunization with Ad26-encoded membrane-bound stabilized Env antigens. Hence, a CoPoP liposome-based HIV-1 vaccine that can generate cross-clade neutralizing antibody immunity could potentially be a component of an efficacious HIV-1 vaccine.

HWJMSC-EVs promote cartilage regeneration and repair via the ITGB1/TGF-ß/Smad2/3 axis mediated by microfractures.

The current first-line treatment for repairing cartilage defects in clinical practice is the creation of microfractures (MF) to stimulate the release of mesenchymal stem cells (MSCs); however, this method has many limitations. Recent studies have found that MSC-derived extracellular vesicles (MSC-EVs) play an important role in tissue regeneration. This study aimed to verify whether MSC-EVs promote cartilage damage repair mediated by MFs and to explore the repair mechanisms. In vitro experiments showed that human umbilical cord Wharton's jelly MSC-EVs (hWJMSC-EVs) promoted the vitality of chondrocytes and the proliferation and differentiation ability of bone marrow-derived MSCs. This was mainly because hWJMSC-EVs carry integrin beta-1 (ITGB1), and cartilage and bone marrow-derived MSCs overexpress ITGB1 after absorbing EVs, thereby activating the transforming growth factor-ß/Smad2/3 axis. In a rabbit knee joint model of osteochondral defect repair, the injection of different concentrations of hWJMSC-EVs into the joint cavity showed that a concentration of 50 µg/ml significantly improved the formation of transparent cartilage after MF surgery. Extraction of regenerated cartilage revealed that the changes in ITGB1, transforming growth factor-ß, and Smad2/3 were directly proportional to the repair of regenerated cartilage. In summary, this study showed that hWJMSC-EVs promoted cartilage repair after MF surgery.

Transcriptomic responses of rabbits to infections by precocious line and wild-type Eimeria media: revealing molecular signatures and pathway differences in liver and duodenum during the peak and terminal phases of oocyst production.

Eimeria media is a principal pathogen responsible for rabbit coccidiosis, targeting the rabbit's intestinal epithelial cells. This parasitism damages the intestinal mucosal barrier, initiating a systemic immune and inflammatory response that jeopardizes the sustainable growth of rabbit farming. To understand the implications of infection on the host's immune and metabolic responses, we employed RNA-Seq to analyze RNA from the liver and duodenum tissues of post-infected rabbits infected with both the precocious line and wild-type strain of E.media. Comprehensive transcriptomic analysis revealed that the two parasites exhibit divergent transcriptomic imprints on host tissues. While the precocious line predominantly modulates immune-centric pathways with significant differential gene enrichment, wild-type strain favors pathways that affect metabolism. In addition, our study pinpointed a set of genes that undergo significant modifications in response to these effects. These revelations grant a fresh avenue to probe deeper into the symbiotic intricacies of the E.media and its rabbit host.

Radiological, histological and clinical side effects of incisor trimming in rabbits.

INTRODUCTION: Incisor malocclusion in rabbits (Oryctolagus cuniculus) is a common clinical problem seen in general practice. Given that the growth rate is about 2 mm per week, a lack of wear quickly leads to feeding difficulties and soft tissue injuries. Therefore, pathologically elongated incisors must be shortened every three to six weeks. The goal of this study was to assess the potential adverse effects on dental and periodontal tissues associated with the three most commonly used trimming methods: nail cutter, diamond-coated cutting disc and diamond burr. The left mandibular incisor of 28 healthy New Zealand rabbits was subjected to four trimmings with one of the three cutting methods. After the fattening period, the mandibles were collected and both mandibular incisors were investigated on dental radiographs, micro-computed tomography scans and histological sections. Dental and periodontal tissue changes were evaluated. This study allowed a more accurate statement of the potential short-term adverse effects of the three trimming methods. At the clinical level, the nail cutter caused the formation of an irregular occlusal surface with sharp edges. Both engine-drive methods allowed the attainment of a smooth surface but the disc was less accurate. Histological evaluation revealed that the primary modifications, including coronal fractures, periodontal ligament widening and inflammation, reparative osteodentine, paracementosis and biofilm accumulation, were found in the nail cutter group.

INTRODUCTION: La malocclusion des incisives chez le lapin (Oryctolagus cuniculus) est un problème clinique courant en médecine générale. Étant donné que le taux de croissance est d'environ 2 mm par semaine, un manque d'usure entraîne rapidement des difficultés d'alimentation et des lésions des tissus mous. Par conséquent, les incisives pathologiquement trop longues doivent être raccourcies toutes les trois à six semaines. L'objectif de cette étude était d'évaluer les effets négatifs potentiels sur les tissus dentaires et parodontaux associés aux trois méthodes de taille les plus couramment utilisées: le coupeongles, le disque de coupe diamanté et la fraise diamantée. L'incisive mandibulaire gauche de 28 lapins néo-zélandais en bonne santé a été soumise à quatre tailles avec l'une des trois méthodes de coupe. Après la période d'engraissement, les mandibules ont été prélevées et les deux incisives mandibulaires ont été examinées sur des radiographies dentaires, des examens micro-tomodensitométriques et des coupes histologiques. Les modifications des tissus dentaires et parodontaux ont été évaluées. Cette étude a permis de mieux cerner les effets indésirables potentiels à court terme des trois méthodes de coupe. Au niveau clinique, le coupe-ongles a entraîné la formation d'une surface occlusale irrégulière avec des bords tranchants. Les deux autres méthodes de taille permettent d'obtenir une surface lisse, mais le disque est moins précis. L'évaluation histologique a révélé que les modifications primaires, y compris les fractures coronaires, l'élargissement et l'inflammation du ligament parodontal, l'ostéodentine réparatrice, la paracémentose et l'accumulation de biofilm, ont été trouvées dans le groupe coupe-ongles.

Enhanced gorilla troops optimizer powered by marine predator algorithm: global optimization and engineering design.

This study presents an advanced metaheuristic approach termed the Enhanced Gorilla Troops Optimizer (EGTO), which builds upon the Marine Predators Algorithm (MPA) to enhance the search capabilities of the Gorilla Troops Optimizer (GTO). Like numerous other metaheuristic algorithms, the GTO encounters difficulties in preserving convergence accuracy and stability, notably when tackling intricate and adaptable optimization problems, especially when compared to more advanced optimization techniques. Addressing these challenges and aiming for improved performance, this paper proposes the EGTO, integrating high and low-velocity ratios inspired by the MPA. The EGTO technique effectively balances exploration and exploitation phases, achieving impressive results by utilizing fewer parameters and operations. Evaluation on a diverse array of benchmark functions, comprising 23 established functions and ten complex ones from the CEC2019 benchmark, highlights its performance. Comparative analysis against established optimization techniques reveals EGTO's superiority, consistently outperforming its counterparts such as tuna swarm optimization, grey wolf optimizer, gradient based optimizer, artificial rabbits optimization algorithm, pelican optimization algorithm, Runge Kutta optimization algorithm (RUN), and original GTO algorithms across various test functions. Furthermore, EGTO's efficacy extends to addressing seven challenging engineering design problems, encompassing three-bar truss design, compression spring design, pressure vessel design, cantilever beam design, welded beam design, speed reducer design, and gear train design. The results showcase EGTO's robust convergence rate, its adeptness in locating local/global optima, and its supremacy over alternative methodologies explored.

The scar-reducing effect of a novel chitosan gel: an in vivo study.

OBJECTIVE: Scar tissue formation, as a normal part of wound healing, initiates in the proliferation phase, continues after the remodelling phase, and may cause an unpleasant appearance or disruption in normal functioning. This study investigated the effects of a topical gel on acute wound healing and reducing scars in a rat model. METHOD: ChitoScar (ChitoTech Company, Iran), a commercial scar-reducing gel based on chitosan, was analysed for antibacterial and antiviral activity through a quantitative suspension test. Its cytotoxic effect was investigated, and then irritation and delayed-type hypersensitivity tests were carried out on rabbits through direct application of the gel. Furthermore, the effect of the chitosan-based gel on wound healing and scar tissue formation was studied in rats with an acute wound in two groups: the treatment group (topical application of the chitosan-based gel); and the control group (without treatment). Histopathological examination was carried out based on the inflammatory cells, collagen fibre, keratinocytes and fibroblasts. RESULTS: Analysis revealed that the chitosan-based gel had no cytotoxicity and caused no erythema, oedema, local or other systemic adverse response. Wound healing occurred earlier in the treatment group, which was a result of a significant increase in re-epithelialisation, angiogenesis, fibroblast population and collagen fibre thickness (p<0.05). In the treatment group, wounds healed completely after 21 days and scars totally disappeared after 28 days, while in the control group, wound healing remained incomplete with distinct scar tissue. CONCLUSION: The results demonstrated the positive effect of the chitosan-based gel on the duration and quality of the wound healing process, as well as minimising the scar tissue formation in this in vivo study.

Keratin Formed Bioadhesive Ophthalmic Gel for the Bacterial Conjunctivitis Treatment.

Keratin has the potential to function as the gel matrix in an ophthalmic formulation for the encapsulation of the macrolide antibiotic azithromycin. The quality of this formulation was thoroughly evaluated through various analyses, such as in vitro release assessment, rheological examination, intraocular retention studies in rabbits, assessment of bacteriostatic efficacy, and safety evaluations. It is worth mentioning that the gel demonstrated shear thinning properties and exhibited characteristics of an elastic solid, thereby confirming its structural stability. The gel demonstrated a notable affinity for mucosal surfaces in comparison to traditional azithromycin aqueous solutions. In vitro release testing revealed that drug release transpired via diffusion mechanisms, following a first-order kinetic release pattern. Additionally, the formulated gel exhibited remarkable antibacterial efficacy against Staphylococcus aureus and Pseudomonas aeruginosa in bacteriostatic evaluations. Lastly, safety assessments confirmed that the gel eye drops induced minimal irritation and displayed no apparent cytotoxicity, indicating their good safety and biocompatibility for ocular application. Thus, these findings indicated that the prepared azithromycin gel eye drops complied with the requisite standards for ophthalmic preparations.

Mucoadhesive, antioxidant, and lubricant catechol-functionalized poly(phosphobetaine) as biomaterial nanotherapeutics for treating ocular dryness.

Dry eye disease (DED) is associated with ocular hyperosmolarity and inflammation. The marketed topical eye drops for DED treatment often lack bioavailability and precorneal residence time. In this study, we investigated catechol-functionalized polyzwitterion p(MPC-co-DMA), composed of 2-methacryloyloxyethyl phosphorylcholine (MPC) and dopamine methacrylamide (DMA) monomers, as potential topical nanotherapeutics for DED. The copolymers were synthesized via random free-radical copolymerization, producing different proportions of catecholic functionalization. All as-prepared polymer compositions displayed good ocular biocompatibility. At a feeding ratio of 1:1, p(MPC1-co-DMA1) can facilitate a robust mucoadhesion via Michael addition and/or Schiff base reaction, thus prolonging ocular residence time after 4 days of topical instillation. The hydration lubrication of MPC and radical-scavenging DMA endow the nano-agent to ease tear-film hyperosmolarity and corneal inflammation. A single dose of p(MPC1-co-DMA1) (1 mg/mL) after 4 days post-instillation can protect the cornea against reactive oxygen species, inhibiting cell apoptosis and the over-expression of pro-inflammatory factors (IL-6 and TNF-α). In clinical assessment, DED-induced rabbit eyes receiving p(MPC1-co-DMA1) could increase lacrimal fluid secretion by 5-fold higher than cyclosporine A. The catechol-functionalized polyzwitterion with enhanced lubricity, mucoadhesion, and anti-oxidation/anti-inflammation properties has shown high promise as a bioactive eye drop formulation for treating DED.

Pasteurella multocida activates apoptosis via the FAK-AKT-FOXO1 axis to cause pulmonary integrity loss, bacteremia, and eventually a cytokine storm.

Pasteurella multocida is an important zoonotic respiratory pathogen capable of infecting a diverse range of hosts, including humans, farm animals, and wild animals. However, the precise mechanisms by which P. multocida compromises the pulmonary integrity of mammals and subsequently induces systemic infection remain largely unexplored. In this study, based on mouse and rabbit models, we found that P. multocida causes not only lung damage but also bacteremia due to the loss of lung integrity. Furthermore, we demonstrated that bacteremia is an important aspect of P. multocida pathogenesis, as evidenced by the observed multiorgan damage and systemic inflammation, and ultimately found that this systemic infection leads to a cytokine storm that can be mitigated by IL-6-neutralizing antibodies. As a result, we divided the pathogenesis of P. multocida into two phases: the pulmonary infection phase and the systemic infection phase. Based on unbiased RNA-seq data, we discovered that P. multocida-induced apoptosis leads to the loss of pulmonary epithelial integrity. These findings have been validated in both TC-1 murine lung epithelial cells and the lungs of model mice. Conversely, the administration of Ac-DEVD-CHO, an apoptosis inhibitor, effectively restored pulmonary epithelial integrity, significantly mitigated lung damage, inhibited bacteremia, attenuated the cytokine storm, and reduced mortality in mouse models. At the molecular level, we demonstrated that the FAK-AKT-FOXO1 axis is involved in P. multocida-induced lung epithelial cell apoptosis in both cells and animals. Thus, our research provides crucial information with regard to the pathogenesis of P. multocida as well as potential treatment options for this and other respiratory bacterial diseases.

Microbiome composition as a potential predictor of longevity in rabbits.

BACKGROUND: Longevity and resilience are two fundamental traits for more sustainable livestock production. These traits are closely related, as resilient animals tend to have longer lifespans. An interesting criterion for increasing longevity in rabbit could be based on the information provided by its gut microbiome. The gut microbiome is essential for regulating health and plays crucial roles in the development of the immune system. The aim of this research was to investigate if animals with different longevities have different microbial profiles. We sequenced the 16S rRNA gene from soft faeces from 95 does. First, we compared two maternal rabbit lines with different longevities; a standard longevity maternal line (A) and a maternal line (LP) that was founded based on longevity criteria: females with a minimum of 25 parities with an average prolificacy per parity of 9 or more. Second, we compared the gut microbiota of two groups of animals from line LP with different longevities: females that died/were culled with two parities or less (LLP) and females with more than 15 parities (HLP). RESULTS: Differences in alpha and beta diversity were observed between lines A and LP, and a partial least square discriminant analysis (PLS-DA) showed a high prediction accuracy (> 91%) of classification of animals to line A versus LP (146 amplicon sequence variants (ASV)). The PLS-DA also showed a high prediction accuracy (> 94%) to classify animals to the LLP and HLP groups (53 ASV). Interestingly, some of the most important taxa identified in the PLS-DA were common to both comparisons (Akkermansia, Christensenellaceae R-7, Uncultured Eubacteriaceae, among others) and have been reported to be related to resilience and longevity. CONCLUSIONS: Our results indicate that the first parity gut microbiome profile differs between the two rabbit maternal lines (A and LP) and, to a lesser extent, between animals of line LP with different longevities (LLP and HLP). Several genera were able to discriminate animals from the two lines and animals with different longevities, which shows that the gut microbiome could be used as a predictive factor for longevity, or as a selection criterion for these traits.

Effect of platelet-rich plasma in Achilles tendon allograft in rabbits.

BACKGROUND: Achilles tendon is composed of dense connective tissue and is one of the largest tendons in the body. In veterinary medicine, acute ruptures are associated with impact injury or sharp trauma. Healing of the ruptured tendon is challenging because of poor blood and nerve supply as well as the residual cell population. Platelet-rich plasma (PRP) contains numerous bioactive agents and growth factors and has been utilized to promote healing in bone, soft tissue, and tendons. OBJECTIVE: The purpose of this study was to evaluate the healing effect of PRP injected into the surrounding fascia of the Achilles tendon after allograft in rabbits. METHODS: Donor rabbits (n = 8) were anesthetized and 16 lateral gastrocnemius tendons were fully transected bilaterally. Transected tendons were decellularized and stored at -80°C prior to allograft. The allograft was placed on the partially transected medial gastrocnemius tendon in the left hindlimb of 16 rabbits. The allograft PRP group (n = 8) had 0.3 mL of PRP administered in the tendon and the allograft control group (n = 8) did not receive any treatment. After 8 weeks, rabbits were euthanatized and allograft tendons were transected for macroscopic, biomechanical, and histological assessment. RESULTS: The allograft PRP group exhibited superior macroscopic assessment scores, greater tensile strength, and a histologically enhanced healing process compared to those in the allograft control group. CONCLUSIONS: Our results suggest administration of PRP on an allograft tendon has a positive effect on the healing process in a ruptured Achilles tendon.

A Shape Memory Polymeric Shield for Protecting Corneal Endothelium During Phacoemulsification.

Background: The purpose of this study was to explore the protective effect of a shape memory polymeric shield on corneal endothelium during phacoemulsification in rabbits. Methods: Poly-(glycerol dodecanedioate) (PGD) with a transition temperature of 24.416°C was prepared to make a shape memory shield with a thickness of 100 µm, an arc length of 14 mm, and a radius of curvature of 8.8 mm. In the control group, a phaco-tip with bevel-down was used to simulate injury to the corneal endothelium by phacoemulsification in rabbits. In the experimental group, the pre-cooled and curled shape memory shield was injected into and removed from the anterior chamber before and after phaco-power release. Anterior segment optical coherence tomography (AS-OCT), confocal microscope, trypan blue/alizarin red staining, and scanning electron microscope were performed to measure endothelial damage after surgery. Results: One day postoperatively, the lost cell ratio of the control group and the experimental group were 28.08 ± 5.21% and 3.50 ± 1.43%, respectively (P < 0.0001), the damaged cell ratios were 11.83 ± 2.30% and 2.55 ± 0.52%, respectively (P < 0.0001), and the central corneal thicknesses (CCT) were 406.75 ± 16.74 µm and 340. 5 ±13.48 µm, respectively (P < 0.0001). Seven days postoperatively, the endothelial cell density (ECD) of the control group and the experimental group were 1674 ± 285/mm2 and 2561 ± 554/mm2, respectively (P < 0.05). The above differences were all statistically significant. Conclusions: This PGD based shape memory shield has a protective effect on corneal endothelium during phacoemulsification. It reduces postoperative corneal edema and ECD decrease in the short term after surgery. Translational Relevance: The shape memory PGD "shield" in this study may have a use in certain human patients with vulnerable corneas of low endothelial cell count or shallow anterior chambers.

Isolation and grouping of RNA phages by Itaru Watanabe et al. (1967).

I. Watanabe et al. isolated approximately 30 strains of RNA phages from various parts of Japan. To isolate RNA phages, they assessed the infection specificity of male Escherichia coli and RNase sensitivity. They found that the isolated strains of RNA phages could be serologically separated into three groups. Furthermore, most of them were serologically related, and the antiphage rabbit serum prepared by one of these phages neutralized most of the other phages. The only serologically unrelated phage was the RNA phage Qß, which was isolated at the Institute for Virus Research, Kyoto University, in 1961.

Wet 3D printing of biodegradable porous scaffolds to enable room-temperature deposition modeling of polymeric solutions for regeneration of articular cartilage.

Tissue engineering has emerged as an advanced strategy to regenerate various tissues using different raw materials, and thus it is desired to develop more approaches to fabricate tissue engineering scaffolds to fit specific yet very useful raw materials such as biodegradable aliphatic polyester like poly (lactide-co-glycolide) (PLGA). Herein, a technique of 'wet 3D printing' was developed based on a pneumatic extrusion three-dimensional (3D) printer after we introduced a solidification bath into a 3D printing system to fabricate porous scaffolds. The room-temperature deposition modeling of polymeric solutions enabled by our wet 3D printing method is particularly meaningful for aliphatic polyester, which otherwise degrades at high temperature in classic fuse deposition modeling. As demonstration, we fabricated a bilayered porous scaffold consisted of PLGA and its mixture with hydroxyapatite for regeneration of articular cartilage and subchondral bone. Long-termin vitroandin vivodegradation tests of the scaffolds were carried out up to 36 weeks, which support the three-stage degradation process of the polyester porous scaffold and suggest faster degradationin vivothanin vitro. Animal experiments in a rabbit model of articular cartilage injury were conducted. The efficacy of the scaffolds in cartilage regeneration was verified through histological analysis, micro-computed tomography (CT) and biomechanical tests, and the influence of scaffold structures (bilayerversussingle layer) onin vivotissue regeneration was examined. This study has illustrated that the wet 3D printing is an alternative approach to biofabricate tissue engineering porous scaffolds based on biodegradable polymers.

Evaluation of the effect of Carica papaya seed on the growth performance of fattening rabbits.

Successful breeding depends on feeding. The present study aims to evaluate the Carica papaya seed effect on the growth performance of rabbits. The zootechnical parameters studied are weight growth, average daily gain, Feed Conversion Ratio, and carcass characteristics of kits. The experiment was conducted on 48 rabbits, divided into 4 groups, for 6 weeks. Forty-eight rabbits were divided into four (04) groups of 3 repetitions of 4 rabbits. The animals were fed diets containing various levels of papaya seed powder at variable contents: 0% (group T0), 4% (group T1), 6% (group T2), and 8% (group T3). At the end of the experiment, three animals were slaughtered in each animal group to assess the quality of the carcasses and organs. 6% of the seeds of Carica papaya significantly improved (p < 0.05) the average daily gain of the kits: T2 (22.40 g / d) compared to the T0 group (11.32 g / d), T1 (12.20 g / d) and T3 (17.53 g / d). The best Feed Conversion Ratio (0.80) was recorded in the animals of group T2. In contrast, the highest carcass yield was recorded in the rabbits of group T3 (62.70%). In conclusion, 6% was optimal in the feed rations of fattened rabbits to improve production performance. Breeders can consider the benefits of introducing Carica papaya seeds into the rabbits' diet.

Lactic acid bacteria reduce bacterial diarrhea in rabbits via enhancing immune function and restoring intestinal microbiota homeostasis.

BACKGROUND: Numerous previous reports have demonstrated the efficacy of Lactic acid bacteria (LAB) in promoting growth and preventing disease in animals. In this study, Enterococcus faecium ZJUIDS-R1 and Ligilactobaciiius animalis ZJUIDS-R2 were isolated from the feces of healthy rabbits, and both strains showed good probiotic properties in vitro. Two strains (108CFU/ml/kg/day) were fed to weaned rabbits for 21 days, after which specific bacterial infection was induced to investigate the effects of the strains on bacterial diarrhea in the rabbits. RESULTS: Our data showed that Enterococcus faecium ZJUIDS-R1 and Ligilactobaciiius animalis ZJUIDS-R2 interventions reduced the incidence of diarrhea and systemic inflammatory response, alleviated intestinal damage and increased antibody levels in animals. In addition, Enterococcus faecium ZJUIDS-R1 restored the flora abundance of Ruminococcaceae1. Ligilactobaciiius animalis ZJUIDS-R2 up-regulated the flora abundance of Adlercreutzia and Candidatus Saccharimonas. Both down-regulated the flora abundance of Shuttleworthia and Barnesiella to restore intestinal flora balance, thereby increasing intestinal short-chain fatty acid content. CONCLUSIONS: These findings suggest that Enterococcus faecium ZJUIDS-R1 and Ligilactobaciiius animalis ZJUIDS-R2 were able to improve intestinal immunity, produce organic acids and regulate the balance of intestinal flora to enhance disease resistance and alleviate diarrhea-related diseases in weanling rabbits.

Optimizing environmental enrichment for Sprague Dawley rats: Exemplary insights into the liver proteome.

BACKGROUND: Considering the expected increase in the elderly population and the growing emphasis on aging-related biomedical research, the demand for aged laboratory animals has surged, challenging established husbandry practices. Our objective was to establish a cost-effective method for environmental enrichment, utilizing the liver as a representative organ to assess potential metabolic changes in response to differing enrichment levels. METHODS: We conducted a six-month study involving 24 male Sprague Dawley rats, randomly assigned to four environmental enrichment groups. Two groups were housed in standard cages, while the others were placed in modified rabbit cages. Half of the groups received weekly playtime in an activity focused rat housing unit. We evaluated hormone levels, playtime behavior, and subjective handling experience. Additionally, liver tissue proteomic analysis was performed. RESULTS: Initial corticosterone levels and those after 3 and 6 months showed no significant differences. Yet, testosterone levels were lower in the control group by the end of the study (p = 0.007). We observed 1871 distinct proteins in liver tissue, with 77% being common across groups. In gene ontology analysis, no specific pathways were overexpressed. In semiquantitative analysis, we observed differences in proteins associated in lipid metabolism such as Apolipoprotein A-I and Acyl-CoA 6-desaturase, which were lower in the control group (p = 0.024 and p = 0.009). Rats in the intervention groups with weekly playtime displayed the least amount of reported distress during inspection or upon room entry and were less prone to accepting treats. Removing animals from their enclosure was most effortless for those in the large cage group. Over time, there was a decrease in conflicts among rats that interacted only twice weekly during playpen time. DISCUSSION: In summary, refining husbandry practices for aging rats is both simple and budget-friendly, with no apparent adverse effects on stress levels, animal development, or relevant metabolic changes in the liver.