Adult Rabbits Research Articles

Reversible effect of castration induced hypogonadism on the morphology of the left coronary arteries in adult male rabbits.

Hypogonadism is associated with an increased risk of coronary artery disease. This study sought to describe the histomorphology of the left coronary arteries of the adult male rabbit following orchiectomy and subsequent testosterone administration. We included 20 adult male rabbits, divided into a baseline group (n=2), an interventional group subjected to castration only (n=6), an intervention group subjected to castration followed by testosterone injection (n=6), and a control group (n=6). Key variables under investigation were serum testosterone levels, the intima-media thickness of coronary arteries, smooth muscle cell density, and adventitial collagen fiber density. The mean coronary arteries' intimal medial thickness was significantly higher in the castrated group than in controls (0.488 mm and 0.388 mm, respectively), while the testosterone-injected group had a mean of 0.440 mm. Mean smooth muscle cell density was significantly lower in the castrated rabbits vs. controls (26.96% and 47.80%, respectively), this observation being reversed with testosterone injection (47.53%). Mean adventitial collagen fiber density was significantly higher in the castrated group than in controls (66.6% and 36.1%, respectively), with a marginal difference after testosterone injection (65.2%). This study demonstrates that castration-induced hypogonadism causes morphological changes in the coronary arteries that are partly reversible using testosterone injections. These findings provide a morphological basis for understanding the role of testosterone in coronary arteries.

The Use of Platelet-Rich Fibrin and Polypropylene Mesh in Repair of Nasal Septal Perforation.

In this study, we aimed to investigate the effectiveness of the use of polypropylene mesh and platelet-rich fibrin (PRF) in nasal septal perforation (NSP) repair. Prospective experimental study. Laboratory. Twenty-four adult male New Zealand rabbits were used in our study. In all subjects, a 10 × 10 mm perforation was created in the septum. The subjects were divided into 3 equal groups according to the different methods used in perforation closure. The bilateral mucosal flap was used in the control group, polypropylene mesh + bilateral mucosal flap in the mesh group, and polypropylene mesh + bilateral mucosal flap + PRF in the mesh + PRF group. NSP treatment success rate was found to be significantly higher in the mesh (4/6, 66.7%) and mesh + PRF (6/6, 100%) groups compared to the control group (0/6, 0%). Re-epithelialization score was higher in the mesh + PRF group and the control group compared to the mesh group. While the necrosis, neutrophil, and abscess scores were highest in the mesh group, they were similar to the control group in the mesh + PRF group. While polypropylene mesh significantly increases the success rate in NSP repair, it causes severe inflammatory responses. However, when polypropylene mesh is combined with PRF, it both increases the rate of perforation closure and significantly reduces the complications associated with the use of mesh.

Reinforcing structures proliferated around a titanium implant inserted into the femur of female rabbits, in a hole smaller than the screw core

One of the basic conditions for the clinical success of osseo-integrated implants is implant stability (Albrektsson and Zarb, 1993). It comprises two components, the primary stability that should be ensured at the time of insertion and the secondary stability, which gradually replaces the primary stability. The primary stability is ensured by the direct contact between the implant surface and that of the bone walls of the insertion hole. Secondary stability begins with the first position of new bone on the implant surface. The aim of the present study was to verify the reinforcing structures proliferated around the titanium implant inserted into the femur of 5 adult female rabbits, in a groove smaller than the screw core diameter. The results suggested that inserting the titanium implant into a hole with a smaller diameter than the screw core produces excessive pressure on the bone, which is felt up to a distance from the bone-implant interface. Consequently, mechanical strength of the bone is decreasing and proliferating bone consolidation formations appears on both periosteum and endosteum areas. Additionally, it was observed that newly proliferated bone extends laterally from the interface to a great distance, causing thickening of the bone wall. The observed structures were represented by branched bone trabeculae and bony protrusions into the medullary cavity, together with bone reshuffling processes with the appearance of numerous osteons, most of which are present at the level of the wall opposite the insertion area.

A Comparison in Terms of Prevalence, Morphological and Histopathological Changes between Eimeria spp. that Infect Local Rabbits (Oryctolagus cuniculus) in Some Regions of Saudi Arabia

Background: The epidemiology of parasitic infections is common in rabbit flocks and poses a significant threat to public health. And the most famous and influential of these causes are coccidia parasites, Coccidiosis in rabbits is an infection caused by intracellular protozoan parasites belonging to Eimeria, which is considered a major cause of significant morbidity and mortality. Methods: A total of 210 fresh feces samples of adult domestic rabbits (Oryctolagus cuniculus) were collected from Riyadh City, Al Kharj and ADilam in Saudi Arabia to examine the incidence of the Eimeria infection of microscopically. Feces concentrated by the floatation technique. After that, freshly collected non-sporulated oocysts were suspended in 2.5% (W/V) potassium dichromate, placed in Petri dishes in the air, and allowed to sporulate at room temperature (25±3oC). The morphometric and specific characteristics of sporulated oocysts were studied by an Olympus microscope (BX51ggTF, OLYMPUS, Tokyo, Japan) using the oil immersion lens. Specimens were taken from all parts intestine and liver, and the tissues were kept in 10% formalin immediately and make tissue sections and that to study the histopathological change under light microscopic. Result: An investigation was conducted in three cities in the Riyadh area (Riyadh, Al Kharj and Adilam) to determine the incidence of Eimeria species that parasitize local rabbits (Oryctolagus cuniculus). The overall frequency of these coccidial illnesses in rabbits in Riyadh City was 45.7%, in Adilam City it was 44.2% and in Al Kharj City it was 37.1%, respectively. There were five different species of Eimeria: E. magna, E. flavescens, E. exigua, E. striedae and E. coecicola, respectively. More than one species of Eimeria oocyst was obtained in the same examined sample. single-infection 13/90 (14.4%), dual-infection 39/90 (43.3%) and triple-infection 38/90 (42.2%). E. magna; E. flavescens; E. exigua; E. stiedae and E. coecicola, respectively. Significant differences (p less than 0.05) in prevalence were observed between the rabbits. Eimeria infection that affects the liver was confirmed by histopathological changes that were noted through the development of parasitic stages in the jejunum, ileum, cecum, end cecum and liver. It is possible to conclude that the current research offers pertinent information that aids in determining potential infection and future preventative measures against rabbit coccidiosis to lessen financial losses in the rabbit industry.

A preclinical model of TB meningitis to determine drug penetration and activity at the sites of disease.

Tuberculosis meningitis (TBM) is essentially treated with the first-line regimen used against pulmonary tuberculosis, with a prolonged continuation phase. However, clinical outcomes are poor in comparison, for reasons that are only partially understood, highlighting the need for improved preclinical tools to measure drug distribution and activity at the site of disease. A predictive animal model of TBM would also be of great value to prioritize promising drug regimens to be tested in clinical trials, given the healthy state of the development pipeline for the first time in decades. Here, we report the optimization of a rabbit model of TBM disease induced via inoculation of Mycobacterium tuberculosis into the cisterna magna, recapitulating features typical of clinical TBM: neurological deterioration within months post-infection, acid-fast bacilli in necrotic lesions in the brain and spinal cord, and elevated lactate levels in cerebrospinal fluid (CSF). None of the infected rabbits recovered or controlled the disease. We used young adult rabbits, the size of which allows for spatial drug quantitation in critical compartments of the central nervous system that cannot be collected in clinical studies. To illustrate the translational value of the model, we report the penetration of linezolid from plasma into the CSF, meninges, anatomically distinct brain areas, cervical spine, and lumbar spine. Across animals, we measured the bacterial burden concomitant with neurological deterioration, offering a useful readout for drug efficacy studies. The model thus forms the basis for building a preclinical platform to identify improved regimens and inform clinical trial design.

The role and mechanism of biological collagen membranes in repairing cartilage injury through the p38MAPK signaling pathway

ObjectiveTo explore the mechanism of the p38MAPK signaling pathway in repairing articular cartilage defects with biological collagen membranes.MethodsThirty-two healthy adult male rabbits were randomly divided into a control group (n = 8), model group (n = 8), treatment group (n = 8) and positive drug group (n = 8). The control group was fed normally, and the models of bilateral knee joint femoral cartilage defects were established in the other three groups. The knee cartilage defects in the model group were not treated, the biological collagen membrane was implanted in the treatment group, and glucosamine hydrochloride was intragastrically administered in the positive drug group. Twelve weeks after the operation, the repair of cartilage defects was evaluated by histological observation (HE staining and Masson staining), the degree of cartilage repair was quantitatively evaluated by the Mankin scoring system, the mRNA expression levels of p38MAPK, MMP1 and MMP13 were detected by real-time fluorescence quantitative PCR (qRT-PCR), and the protein expression levels of p38MAPK, p-p38MAPK, MMP1 and MMP13 were detected by Western blotting. The results after the construction of cartilage defects, histological staining showed that the articular cartilage wound was covered by a large capillary network, the cartilage tissue defect was serious, and a small amount of collagen fibers were formed around the wound, indicating the formation of a small amount of new bone tissue. In the treatment group and the positive drug group, the staining of cartilage matrix was uneven, the cytoplasmic staining was lighter, the chondrocytes became hypertrophic as a whole, the chondrocytes cloned and proliferated, some areas were nest-shaped, the cells were arranged disorderly, the density was uneven, and the nucleus was stained deeply. The Mankin score of the model group was significantly higher than that of the control group, while the Mankin scores of the treatment group and positive drug group were significantly lower than that of the model group. The results of qRT-PCR detection showed that compared with the control group, the expression level of the p38MAPK gene in the model group did not increase significantly, but the gene expression levels of MMP1 and MMP13 in the model group increased significantly, while the gene expression levels of MMP1 and MMP13 decreased significantly in the treatment group and positive drug group compared with the model group. The results of Western blot detection showed that compared with the control group, the expression level of p38MAPK protein in the model group was not significantly increased, but the phosphorylation level of p38MAPK protein and the protein expression levels of MMP1 and MMP13 were significantly increased in the model group, while the phosphorylation level of p38MAPK protein and the protein expression levels of MMP1 and MMP13 in the treatment group and positive drug group were significantly lower than those in the model group.ConclusionThe biological collagen membrane can regulate the expression of MMP1 and MMP13 and repair the activity of chondrocytes by reducing the phosphorylation level of p38MAPK and inhibiting the activation of the p38MAPK signaling pathway, thus improving the repair effect of articular cartilage defects in rabbits. The P38MAPK signaling pathway is expected to become an important molecular target for the clinical treatment of cartilage defects in the future.

Clinical and pathomorphological changes in the rabbit retina after an injection of various doses of the cytostatic melphalan

Background: In recent years, there have been individual reports on intracameral chemotherapy (ICC) for aqueous seeding in retinoblastoma. The effect of melphalan on the structures of the ocular anterior segment (including the cornea, iris and anterior lens capsule) is however, still unknown, since no relevant experimental studies have been carried out so far. Purpose: To experimentally assess the changes in the rabbit anterior segment induced by intracameral injection of various concentrations of the alkylating cytostatic melphalan. Material and Methods: Twelve adult Chinchilla rabbits (22 eyes; age, 5–6 months; weight, 2.5–3 kg) were involved in this experimental study and maintained in the vivarium of the Filatov institute in separate cages under standard conditions. Results: After a 5-µg melphalan injection, corneal and iris changes were reversible and the lens was still clear. With an increase in melphalan concentration in injection solution (to 10, 15 and 20 µg) and time point (to 1 month and 3 weeks) after injection, degenerative changes in some epithelial cells of the iris became irreversible, anterior capsular cataract developed, but the cornea and anterior chamber aqueous remained clear. After a single 20-µg intracameral injection of melphalan, there was depigmentation of the iris, posterior synechia and anterior capsular cataract. Conclusion: Clinical and ultrastructural responses of ocular anterior segment tissue to intracameral melphalan injection depended on the injected dose and time point after injection. Most cells of examined tissues showed the capability to restore their ultrastructure following ceasing of the toxic effect of the drug.

A rabbit model of ear otitis established using the Malassezia pachydermatis strain C23 from dogs.

Fungal infections are a growing problem for both humans and animals due to the emergence of pathogenic strains resistant to modern antifungal treatments. To evaluate the efficacy of new antifungal drugs, it is essential to develop animal models that demonstrate typical responses to both the infection (pathogenesis and clinical course) and to the treatment, including adverse effects. In this study, we established a rabbit otitis model by infection of an aggressive multidrug-resistant strain from dogs, Malassezia pachydermatis C23, with no need for concomitant immunosuppression. Twenty healthy adult male gray giant rabbits (1 year old, 5.5 kg) were inoculated once with M. pachydermatis C23 at 108 colony-forming units/mL. We observed the clinical signs of the disease and collected ear smears and blood samples every 5 days. The infection progressed rapidly and exhibited characteristic clinical signs without spontaneous recovery for at least 1 month. In fact, substantial deterioration was observed as evidenced by blood parameters. This rabbit otitis model established using an aggressive drug-resistant fungus strain without immunosuppression could prove valuable for testing novel antifungal agents.

Rabbit model for the study of nasal tip plasty: a comparative cephalometric analysis after rhinoplasty

Background Open rhinoplasty and septoplasty have emerged as popular surgical techniques for both functional and aesthetic procedures. To study open rhinoplasty with or without septoplasty, the use of animals is necessary. However, no reports have been published on radiologic methods for evaluating rhinoplasty or nasal tip plasty in animals using cephalometry. In this study, a validated model of open rhinoplasty and septoplasty was utilized in rabbits to establish radiographic guidelines for assessing the degree of tip plasty in these animals.Methods Eight adult New Zealand rabbits were used to establish an autologous septal extension graft (SEG) model. The rabbits underwent concurrent submucosal septal resection and open rhinoplasty. The SEG was implanted using nasal septal cartilage. To evaluate the results of nasal tip plasty, lateral-view X-ray images were obtained preoperatively, as well as 2 days, 2 months, and 12 months postoperatively.Results This open rhinoplasty rabbit model appears to be a practical tool for studying open rhinoplasty and tip plasty, demonstrating statistically significant results following SEG implantation. Furthermore, it is suitable for training purposes, specifically for the submucosal resection of septal cartilage.Conclusions This study presents a statistical analysis of the long-term (1-year) postoperative results of SEG implantation, using experimental procedures like those utilized in humans. Through a cephalometric comparison of rabbit noses, the effect of various SEG and tip plasty methods on the rabbit nose can be objectively measured.

Ameliorative Role of Grape Seed Extract (Vitis Vinifera) on Gemcitabine- Induced Testicular Damage in Rabbits

Spermatogenesis is a highly conserved and regulated process and it is sensitive to fluctuations in the physical and chemical environment. Gemcitabine is a novel antimetabolic anticancer drug used frequently in the treatment of many cancers. Gemcitabine may disrupt spermatogenesis by targeting various testicular cell types. Grape seed extract is a natural product, recently identified as one of the most powerful antioxidants. In addition, it has been reported to exert anticarcinogenic effects. This current work aimed to study the effect of gemcitabine on the testicular tissue of local adult rabbits and to evaluate the possible protective role of Grape seed extract. A experimental study was performed on twenty seven adult male local rabbits, were divided into three groups, nine rabbit in each group as following: group (A): animals of control group received normal saline injection, group (B): animals of treated group received therapeutic dose of gemcitabine alone in a dose of 25 mg/kg body weight intraperitoneally once per week for six successive weeks and group (C): served as protective group and was concomitantly treated with grape seeds extract by oral gavages in a dose of 250 mg/kg body weight and gemcitabine in a dose of 25 mg/kg body weight intraperitoneally once per week for six successive weeks. The results of the present investigation showed that gemcitabine toxicity produced significant structural changes in the testis of group B, gemcitabine treated group, in the form of multiple distortion of the seminiferous tubules, with cellular disorganization, testicular tubular cell degeneration, necrosis, tubular atrophy, desquamation and sloughing of the seminiferous epithelium which was accumulated in the centre of the seminiferous tubules in the form of degenerated tissue. Many seminiferous tubules showed widely spaced spermatogenic cells. Karyopyknosis, disappearance of interstitial cells of Leydig and necrotic Sertoli cells, progressive tubular and interstitial testicular damage together with spermatogenic arrest was an initial necrotic change induced by gemcitabine exposure. Disorganization of spermatogenic cells, an interruption in spermatogenesis process and the seminiferous tubules are devoid of sperms was also showed in this study. Sections from the testes of animals received therapeutic dose of gemcitabine and treated by grape seed extract, group (C) were showing partial preservation of the normal structure of the seminiferous tubules. Most of them more or less resembled the normal structure. It could be concluded that gemcitabine caused marked alterations in the structure of the seminiferous tubules of the rabbit testis that may be minimized by administration of grape seed extract. Our findings simply revealed that grape seeds extract treatment significantly inhibits testicular cell apoptosis, which suggests that apoptosis may be one of the underlying mechanisms by which grape seeds extract protects against gemcitabine induced defective spermatogenesis.

Inhibition of urethral stricture by a catheter loaded with nanoparticle/ pirfenidone complexes.

Background: Urethral strictures are common injurious conditions of the urinary system. Reducing and preventing urethral strictures has become a hot and challenging topic for urological surgeons and related researchers. In this study, we developed a catheter loaded with nanoparticle/pirfenidone (NP/PFD) complexes and evaluated its effectiveness at inhibiting urethral stricture in rabbits, providing more references for the clinical prevention and reduction of urethral stenosis. Methods: Twelve adult male New Zealand rabbits were selected and divided into the following four groups in a ratio of 1:1:1:1 using the random number table method: Group A, sham; Group B, urethral stricture (US); Group C, US + unmodified catheter; and Group D, US + NP/PFD catheter. On the 30th day after modelling, retrograde urethrography was performed to evaluate urethral stricture formation, and histopathological examination was performed on the tissues of the corresponding surgical site. Meanwhile, changes in the expression level of Transforming growth factor β1 (TGF-β1) in the tissues were detected by immunohistochemistry. Results: The NP/PFD complexes adhered uniformly to the catheter surface. They remained on the surface of the catheter after insertion into the urethra. In addition, the NP/PFD complexes spread into the urethral epithelium 2weeks after surgery. Ultimately, urethral strictures were significantly reduced with the placement of the NP/PFD complex catheter. Conclusion: Our catheter loaded with NP/PFD complexes effectively delivered PFD to the urethral epithelium through continuous local delivery, thereby reducing fibrosis and stricture after urethral injury, which may be associated with the inhibition of TGF-β1 expression.

The effect of platelet-rich fibrin, platelet-rich plasma, and concentrated growth factor in the repair of full thickness rotator cuff tears

Rotator cuff lesions rank among the prevalent causes of shoulder pain. Combining surgical interventions with growth factors, scaffolds, and stem cell therapies can effectively decrease the likelihood of rotator cuff repair recurrence. Platelet-rich plasma (PRP), platelet-rich fibrin (PRF), and concentrated growth factor (CGF), isolated from blood and rich in growth factors, have a critical role in cell migration, cell proliferation, and angiogenesis during the tissue regeneration process. Investigations have further substantiated the beneficial impact of PRP and PRF on the biomechanical and histologic attributes of the tendon-bone interface. We aimed to investigate the effectiveness of CGF compared with PRF and PRP in the repair of rotator cuff lesions as a new treatment strategy. Incision was performed on both shoulder regions of 21 adult rabbits. After 8 weeks, both shoulders of the rabbits were repaired by suturing. PRF and CGF were administered to 2 separate groups along with the repair. Tissues were collected for biomechanical measurements and histologic evaluations. Histologically, CGF, PRF, and PRP showed similar results to the healthy control group. The level of improvement was significant in the PRF and PRP groups. In the PRF group, the distribution of Ki67 (+), CD31 (+), and CD34 (+) cells was determined intensely in the tendon-bone junction regions. Apoptotic cells increased significantly in the repair group compared with the healthy group, whereas fewer apoptotic cells were found in the PRF-, PRP-, and CGF-applied groups. In the biomechanical results, no statistical difference was recorded among the groups. The use of PRF, PRP, and CGF in rotator cuff repair shows promise in shortening the treatment period and preventing the recurrence of rotator cuff lesions.

Therapeutic Ultrasound for Enhanced Corneal Permeability to Macromolecules.

Topically applied macromolecules have the potential to provide vision-saving treatments for many of the leading causes of blindness in the United States. The aim of this study was to determine if ultrasound can be applied to increase transcorneal drug delivery of macromolecules without dangerously overheating surrounding ocular tissues. Dissected corneas of adult rabbits were placed in a diffusion cell between a donor compartment filled with a solution of macromolecules (40, 70 kDa, or 150 kDa) and a receiver compartment. Each cornea was exposed to the drug solution for 60 minutes, with the experimental group receiving 5 minutes of continuous ultrasound or 10 minutes of pulsed ultrasound at a 50% duty cycle (pulse repetition frequency of 500 ms on, 500 ms off) at the beginning of treatment. Unfocused circular ultrasound transducers were operated at 0.5 to 1 W/cm2 intensity and at 600 kHz frequency. The greatest increase in transcorneal drug delivery seen was 1.2 times (P < .05) with the application of pulsed ultrasound at 0.5 W/cm2 and 600 kHz for 10 minutes with 40 kDa macromolecules. Histological analysis revealed structural damage mostly in the corneal epithelium, with most damage occurring at the epithelial surface. This study suggests that ultrasound may be used for enhancing transcorneal delivery of macromolecules of lower molecular weights. Further research is needed on the long-term effects of ultrasound parameters used in this study on human ocular tissues.

Preventive Effect of Molecular Iodine in Pancreatic Disorders from Hypothyroid Rabbits.

Pancreatic alterations such as inflammation and insulin resistance accompany hypothyroidism. Molecular iodine (I2) exerts antioxidant and differentiation actions in several tissues, and the pancreas is an iodine-uptake tissue. We analyzed the effect of two oral I2 doses on pancreatic disorders in a model of hypothyroidism for 30 days. Adult female rabbits were divided into the following groups: control, moderate oral dose of I2 (0.2 mg/kg, M-I2), high oral dose of I2 (2.0 mg/kg, H-I2), oral dose of methimazole (MMI; 10 mg/kg), MMI + M-I2,, and MMI + H-I2. Moderate or high I2 supplementation did not modify circulating metabolites or pancreatic morphology. The MMI group showed reductions of circulating thyroxine (T4) and triiodothyronine (T3), moderate glucose increments, and significant increases in cholesterol and low-density lipoproteins. Acinar fibrosis, high insulin content, lipoperoxidation, and overexpression of GLUT4 were observed in the pancreas of this group. M-I2 supplementation normalized the T4 and cholesterol, but T3 remained low. Pancreatic alterations were prevented, and nuclear factor erythroid-2-related factor-2 (Nrf2), antioxidant enzymes, and peroxisome proliferator-activated receptor gamma (PPARG) maintained their basal values. In MMI + H-I2, hypothyroidism was avoided, but pancreatic alterations and low PPARG expression remained. In conclusion, M-I2 supplementation reestablishes thyronine synthesis and diminishes pancreatic alterations, possibly related to Nrf2 and PPARG activation.

Comperative Study on Anesthetic Effect of Xylazine-Ketamine And Diazepam-Ketamine In Rabbit Model

This study was conducted to investigate the anesthetic effects of Xylazine-ketamine and Diazepam-ketamine in rabbits. Twelve adult white New-Zealand rabbits weighing 1.3+0.2 kg, were divided into two groups. A (Xylazine 5mg/kg – ketamine 35mg/kg) and B (Diazepam 5mg/kg – ketamine 35mg/kg). However, the following parameters were observed: analgesic effects (onset and duration) and clinical-parameters (means of heart-rates/BPM, respiratory-rates/BPM and rectal temperature. The onset was significantly p&lt;0.05 increased, and the duration was significantly p&gt;0.05 decreased in A. The heart-rate and the respiratory-rate was significantly p&lt;0.01 decreased in A. But the rectal temperature decreased non-significantly p&gt;0.05 in both groups. General observations: in Group A, urination, nasal-discharge, salivation and lacrimation were present, in Group B, defecation, corneal-reflex and pedal-reflex were observed at their peak. It was concluded that the xylazine-ketamine is used for clinical/surgical procedures, while diazepam-ketamine may further be investigated by using other analgesics with this combination.

Preclinical In-Vivo Safety and Toxicokinetics of D-PLEX100 in an Abdominal Surgery Incision Model in Juvenile Miniature Swine.

D-PLEX100 (D-PLEX) is a novel product candidate made of a polymer-lipid-based matrix (PLEX platform) which contains doxycycline that is being released at a constant rate for 30days. D-PLEX was developed to prevent surgical site infections, which are a major global health challenge. Previous studies have shown its safety in adult humans, adult swine, and adult rabbits. The aim of this study was to assess the toxicity and safety of D-PLEX also in juvenile animals to support future clinical trials in pediatric patients. Yucatan miniature swine were selected as a model, primarily due to their relatively larger mass. D-PLEX or placebo (formulation without doxycycline) was administered locally to abdominal incisions, and the animal's safety parameters were followed for 9months and compared to sham-control swine. There was no evidence of any systemic safety concern or local toxicity at the incision site in D-PLEX-treated animals. D-PLEX was detected after 1month and was fully resorbed at the 3-month time point. The surgical incision sites were fully healed at the 6-month time point in all D-PLEX-treated animals. Toxicokinetic (TK) assessments revealed that doxycycline exhibited low Cmax and therefore minimal systemic exposure following a single dose of local administration. This study provides evidence for the safety of D-PLEX and PLEX-based formulation in juvenile miniature swine and supports its further testing in clinical pediatric population. In addition, it can be used as a reference for future preclinical studies aiming to evaluate the safety of other PLEX-based product candidates for the pediatric population.

Effects of imidacloprid contaminated feed exposure on the spleen, lymph node, and mucosa-associated lymphoid tissues of adult male rabbits (Oryctolagus cuniculus)

Effects of imidacloprid contaminated feed exposure on the spleen, lymph node, and mucosa-associated lymphoid tissues of adult male rabbits (Oryctolagus cuniculus)

Exploring the Potential of Hesperidin in Preventing Hypertrophic Scars: Insights from a Rabbit Ear Model.

Hypertrophic scars, commonly occurring after trauma or surgery in critical areas like the head and joints, pose significant challenges to both physical and mental health due to their impact on skin function and aesthetics. While the complex pathogenesis involves fibroblast activation and collagen deposition, effective treatments are lacking, underscoring the importance of exploring pathogenesis and targeted therapies. Hesperidin, a bioactive compound in citrus fruits with diverse health benefits, including anti-fibrotic and anti-angiogenic effects, is the focus of this study with the aim of investigating its impact on hypertrophic scar formation, given its potential to promote blood flow and improve skin microcirculation. This study aimed to observe the inhibitory effect of topical hesperidin on hypertrophic scars in rabbits. A total of 8 healthy adult New Zealand white rabbits were used to establish a rabbit hypertrophic scarring animal model. Five wounds were created on each rabbit's two ears, with three wounds on the left ear (groups A, B, and C) and two wounds on the right ear (groups D and E). After six days of wound drying postoperatively, the wounds were locally treated with medication as followed: group A, 0.1% hesperidin; group B, 1% hesperidin; group C, 1% triamcinolone acetonide; group D, Vaseline; and group E, blank control without any medication. After 28 days, the scar tissue samples were collected for histological examination. The results showed that the scar texture of groups B and C was softer and lighter in color, and the number of fibroblasts, capillaries, and inflammatory cells in the tissue was significantly less than those in the other three groups. The hypertrophic scar indices of groups B and C were significantly smaller than those of groups A, D, and E, and the difference was statistically significant (P < 0.05). There were no significant difference between groups B and C. Topical application of hesperidin demonstrated promising potential for reducing hypertrophic scar formation in rabbits.

Assessment of Subchronic Dermal Toxicity of Ziziphus oenoplia extract incorporated Carbopol hydrogel on New Zealand White Rabbits

Since the ancient times herbal formulations have been used in the ailment of various diseases. The plant Ziziphus oenoplia is also known for its various pharmacological activities including wound healing property. But evaluation of the safety of the herbal formulations after application is necessary for their acceptance in the scientific community. As a result, in the current research work sub-chronic dermal toxicity of Ziziphus oenoplia extract incorporated herbal hydrogel was conducted to evaluate its safety profile upon application on the skin. Three different doses of extract loaded hydrogel (1g/kg, 2g/kg and 4g/kg body weight of animals), blank (4g/kg body weight) and control (0.9% NaCl solution) was applied on 15 adult healthy New Zealand White Rabbits in groups of 3 animals each. Application was done on the dorso-ventricular trunk of the rabbits and the animals were observed for 28 days for any clinical signs of intoxication, food consumption and change in body weight gain. After completion of the experiment no skin irritation such as erythema, edema or eschar formation was observed in all the animal groups. No signs of mortality or morbidity was seen. Food consumption was found to be normal and no drastic increase in body weight gain of the rabbits was observed in the control, blank and test groups of rabbits. From this study it was concluded that the Ziziphus oenoplia extract loaded Carbopol hydrogel was non-toxic and could be safely used as a dermal formulation.

Osseointegration effects of whey protein (histological and histomorphological observations): An experimental study on rabbits

Background: Whey protein is the green-yellow colored, liquid portion of the milk, and it is also called the cheese serum, it is obtained after the separation of curd, during the coagulation of the milk. It contains a considerable amount of α-helix pattern with an evenly distributed hydrophobic and hydrophilic as well as basic and acidic amino acids along with their polypeptide chain. The major whey protein constituents include β-lactoglobulin (β-LG),α-lactalbumin (α-LA), immunoglobulins (IG), bovine serum albumin (BSA), bovine lactoperoxidase (LP), bovine lactoferrin (BLF) and minor amounts of a glycol macro peptide (GMP). Osseointegration can be defined as a process that is immune driven which leads to the formation of the new bone surrounding the surface of the implant rather than a pure response of the bone. Titanium can activate a balance recognized to be tolerogenic with a peri-implant tissue leading to a "foreign body equilibrium (FBE)" response. Materials and methods: Twelve adult male white New Zealand healthy rabbits were used in this study, the animals were divided into two groups according to the time of scarification as follows; 2 and 6 weeks after the implantation (6 rabbits will be sacrificed for each group). Results: Statistical analysis showed that there is a highly significant difference in all parameters between the experimental group and control group at 2 weeks and 6 weeks periods. Histological results at 2 weeks period showed thread formation in whey protein and control group, distribution of osteocyte cells and osteoblast was higher in whey protein, and the bone trabecular area was also larger in whey protein groups but at 6 weeks showed mature bone in whey protein groups while in control group still woven bone. Conclusions: Whey protein is an effective in osseointegration because it enhances bone formation.