Experimental Rabbit Research Articles

Establishment of an animal model to study the effects of amputation on the cardiovascular system

Lower limb amputation is a significant change in body structure. Loss of muscle, blood vessels, and blood leads to a redistribution of blood flow and changes in resistance at the end of blood vessels. In view of the significant increase in the prevalence of cardiovascular disease after lower limb amputation, the mechanism of which is still unclear, this study aims to establish an animal research model that can verify and explore the effects of amputation on cardiovascular system, and provide the experimental basis for subsequent animal experiments when exploring the effect of different amputation levels on the cardiovascular system. SPF New Zealand rabbits were divided into normal group ( n = 6) and amputation group ( n = 6). The amputation group was treated with above-knee amputation. The changes of low-density liptein cholesterol (LDL-C) and total cholesterol (TC) in serum of all the rabbits were monitored regularly after the surgery. The arterial pathological examination was conducted after the experimental rabbits were executed. The results showed that compared with the normal group, serum LDL-C content and TC content in the amputation group were significantly increased ( P<0.05); The blood vessels of the amputated rabbits had pathological changes such as degeneration and necrosis of smooth muscle cells in the middle membrane layer and rupture of elastic fibers. At the abdominal aorta and aortic arch, the elastic fiber area expression percentage (EFEP) of the experimental group was significantly lower than that of the normal group. The results suggest that the cardiovascular system of rabbits has the tendency of decreased arterial elasticity and lipid deposition in blood after amputation, indicating that the animal research model on the effect of amputation on the cardiovascular system has been successfully established, and can provide an experimental platform for further study on the mechanism of the effect of amputation on the cardiovascular system.

Dynamic Detection of HbA1c Using a Silicon Nanowire Field Effect Tube Biosensor.

As an emerging diabetes diagnostic indicator and a dynamic change index, HbA1c can not only reflect the average blood glucose level over a period of time but can also well predict the incidence of related microvascular complications. It is important to develop a detection method that can dynamically characterize HbA1c. Silicon nanowire (SiNW) devices were mass-produced using top-down sputtering technology, and a microdialyzer was installed in a SiNW field effect tube biosensor detection system. Finally, the detection system was used to detect HbA1c levels quantitatively and dynamically in experimental rabbits. Various measurements showed that mass-produced SiNW devices have ideal dimensions, stable structures, and good performance. A series of microscopy results showed that the SiNW surface can be functionalized for intermolecular interactions. The addition of a dialysis device can effectively overcome Debye shielding, making the blood test similar to the pure standard test. Finally, the dynamic detection of HbA1c within 40 h was realized. SiNW biosensors are capable of the dynamic detection of biomolecules, and dynamic observation of the interaction between blood glucose and HbA1c provides new ideas for the diagnosis and treatment of patients with diabetes. Therefore, the SiNW biosensor can reflect the dynamic changes in HbA1c in a shorter time, which has a certain potential value in the clinical treatment of diabetes.

Curcumin loaded polycaprolactone scaffold capable of anti-inflammation to enhance tracheal cartilage regeneration

An inflammatory reaction is one of the primary reasons for deteriorating tracheal cartilage regeneration in vivo, hindering tracheal defect restoration with prominent fibrosis and granulation hyperplasia. Therefore, effective anti-inflammatory therapeutic strategies may considerably promote tracheal cartilage regeneration and tracheal defect restoration. We prepared a porous ring-shaped Cur/PCL scaffold by loading curcumin (Cur), an anti-inflammatory compound, into polycaprolactone (PCL) using the supercritical CO2 foaming method. Our results confirmed that the Cur/PCL possessed similar porosity with the PCL alone scaffold. The Cur loaded within the Cur/PCL scaffold exhibited sustained release kinetics, stability and a favorable anti-inflammation property in vitro. Moreover, The Cur/PCL scaffold displayed gratifying biocompatibility and supported ring-shaped tracheal cartilage regeneration. In addition, the engineered ring-shaped tracheal cartilage in the Cur/PCL group showed a potent anti-inflammatory effect on maintaining the cartilaginous phenotype and enhanced tracheal cartilage regeneration when subcutaneously implanted into an autologous rabbit. Furthermore, the engineered cartilage in the Cur/PCL group exerted a favorable anti-inflammatory capacity to significantly suppress fibrogenesis and granulation hyperplasia, enhancing tracheal cartilage regeneration and elevating survival rate of experimental rabbits after orthotopic transplantation. This study provides an effective strategy to prepare an anti-inflammatory scaffold for enhancing cartilage regeneration in vivo and repairing tracheal cartilage defects.

Changes in serum lipid profiles of weaner rabbits fed diets fortified with processed Garcinia kola seed

Background: A fifty-six (56) day experiment was conducted at the small animal experimental unit of Federal College of Wildlife Management, New-Bussa, Niger State to determine the effect of fortifying the feed of weaned rabbits with graded levels of Garcinia kola (G. kola). Methods: Forty unsexed New-Zealand white rabbits weighing between 0.90-0.92kg used for this experiment were randomly distributed into five dietary treatments tagged T1, T2, T3, T4 and T5 using a Completely Randomized Design (CRD). The experimental rabbits were fed with Iso-Caloric and Iso-Nitrogenous diets that are rich in lipids with a very high metabolizable energy (M/E). Rabbits in T1which served as the control were fed plain diets not fortified with G. kola. Rabbits in treatments 2 to 5 were fed diets fortified with graded level of processed G. kola seeds at 5g/100g, 10g/100g, 15g/100g and 20g/100g respectively and the animals were fed at 10% of their body biomass by monitoring the weight on weekly basis. Results: Data obtained from this study revealed that feeding of weaner rabbits with feed fortified with powdered G. kola seed produced a significant (p&lt;0.05) dose-dependent serum-lipid lowering effects as compared to the control group, this may be mediated by some of the phytochemical and nutritional constituents of G. kola. The phytochemical analysis revealed that values of Tannin Flavonoids, Saponin and Alkaloids ranges from 5.94 ± 0.58%, 1.57 ± 0.37%, 3.46 ± 0.365% and 6.58 ± 0.38% respectively while the results of the Proximate analysis revealed that G. kola seed contained 8.51 ± 0.045% Moisture, 2.39 ± 0.420% Protein, 4.65 ± 0.365% Ash and 75.91 ± 2.265%NFE. Conclusion: This research work has revealed that G. kola seed has a hypolipidemic effect when consumed and that consumption of G. kola seed may help in the reduction of the incidence of cardiovascular.

Effect of Cissus quadrangularis Hydrogel on Enhancing Osseointegration of Titanium Implant to Bone: An In Vivo Study

The aim of the study was to evaluate the osteogenic potential of Cissus quadrangularis (CQ) hydrogel in enhancing the osseointegration of titanium to the bone in an experimental rabbit model. Six adult male New Zealand white rabbits were used in this study. A total of 24 implants (12 coated test implants and 12 uncoated control implants) were placed in these 6 rabbits. A polyethylene glycol (PEG) hydrogel was prepared with the C. quadrangularis hydrogel in which the test implants were coated. Each rabbit was operated on both hind legs and one implant, each, was placed in the femur and tibia. Hence, one rabbit received four implants [two test implants (HG coated) and two control implants (uncoated)]. The animals were sacrificed after 4 weeks, and the specimens were histomorphometrically analyzed. The bone-to-implant contact (BIC) and the bone area fraction occupancy (BAFO) were calculated using Image J analysis. The statistically analyzed values which were obtained by paired t-test, revealed that the average mean values were higher in the test implants (coated) than the control implants (uncoated). The BIC values of the test implants were not significantly different from the control implants in the case of both femur and tibia (p >0.05). The test implants showed significantly increased BAFO values in femur (p <0.05). However, the BAFO values of test implants in tibia did not vary significantly from the control implants. Based on the findings of the study, the authors conclude that the coating of C. quadrangularis hydrogel enhances the osseointegration of titanium implants to bone. The further studies need to be designed to check the osseointegrative potential of C. quadrangularis. The findings of this study suggest that the C. quadrangularis hydrogel is a potent osteogenic material that can reduce the osseointegration period and thus enhance the patient compliance toward implant treatment.

Autologous Bilayered Adipose-Derived Mesenchymal Cell-Gelatin Sheets Reconstruct Ureters in Rabbits.

Repair of ureteral defects or strictures due to disease or trauma is usually dependent upon surgery that often requires either reoperation or an alternative treatment. By taking advantage of tissue engineering and regenerative techniques, it may be possible to define new approaches to ureteral repair. In this study, we fabricated autologous bilayered adipose-derived mesenchymal cell (AMC)-gelatin sheets and transplanted them into rabbits to replace surgically excised ureteral segments. AMCs harvested from abdominal adipose tissues of female New Zealand white rabbits were cultured on collagen-coated dishes and labeled with PKH26, a red fluorescent dye, for later identification. Monolayers of the cultured PKH26-labeled AMCs were detached and applied to gelatin hydrogel sheets. Two gelatin sheets were then united with the AMC monolayers apposed together, forming a bilayered AMC-gelatin sheet. Following each partial ureterectomy, a bilayered autologous AMC-gelatin sheet was transplanted, joining the proximal and distal ends of the remaining ureter (n = 9). Control animals underwent the same procedure except that the transplant was achieved with a bilayered acellular-gelatin sheet (n = 9). At 4 and 8 weeks after transplantation, the proximal regions of ureters treated with the control bilayered acellular-gelatin sheets exhibited flexures and dilations, which are not characteristic of unoperated ureters. In contrast, the bilayered AMC-gelatin sheet-transplanted rabbits did not have ureteral flexures or dilations. About midway between the proximal and distal ends, both the control and experimental reconstructed ureteral walls had smooth muscle layers; however, those in the experimental reconstructed ureteral walls were significantly thicker and better organized than those in the control reconstructed ureteral walls. Some AMCs differentiated into smooth muscle marker-positive cells. The experimental ureteral walls contained smooth muscle cells derived from the PKH26-labeled AMCs and others that were derived through migration and differentiation of cells from the remaining proximal and distal ends of the original ureter. In addition, the lumina of the 8-week reconstructed ureteral tissues in experimental rabbits did not show histological strictures as seen in the control ureters. These results suggest that the bilayered AMC-gelatin sheets have the potential to replace defective tissues and/or reconstruct damaged ureters. Impact Statement To reconstruct ureter tissues following partial ureterectomy, we fabricated bilayered adipose-derived mesenchymal cell (AMC)-gelatin sheets based on cell sheet engineering principles. The bilayered AMC-gelatin sheets were transplanted into rabbits to replace a surgically excised ureteral segment. At 4 and 8 weeks after, the ureters that received bilayered AMC-gelatin sheets did not exhibit severe flexures, dilations, or strictures. The experimental ureteral walls had smooth muscle marker-positive cells that were differentiated from the AMCs, and similar cells were present in the adjacent intact ureteral tissues. Therefore, the bilayered AMC-gelatin sheets have the potential to reconstruct ureters damaged through disease or trauma.

The Antibacterial Activity Comparison between Novel Carbon-Based Nanofilm Coated Titanium Alloy and Co-Cr-Mo Alloy.

Objective The purpose of this study was to reveal the antibacterial activity of carbon-based nanofilm titanium alloy. Methods The experiments were performed both in vitro and in vivo of animals using two circular-piece test specimens of the same specification, which were made from carbon-based nanofilm coated titanium alloy and commonly used in artificial joints Co-Cr-Mo alloy, respectively. In the in vitro experiments, the two test specimens were cocultured with standard strains of Staphylococcus aureus and Escherichia coli, and the antibacterial properties of the two test specimens were evaluated via inhibition zone size, scanning electron microscopy, fluorescence staining, colony forming unit count, and others; the cytotoxicities of the two test specimens were evaluated by coculturing and them with rabbit bone marrow mesenchymal stem cells (BMSCs). In the in vivo experiments, the two test specimens were implanted in the muscle tissue of experimental rabbits to evaluate their histocompatibilities. Results Both in vitro cocultures of the carbon-based nanofilm titanium alloy and the Co-Cr-Mo alloy with Staphylococcus aureus and Escherichia coli failed to form inhibition zone. However, some biofilms were observed on the surface of the Co-Cr-Mo alloy. Fewer bacteria adhered to the carbon-based nanofilm titanium alloy can be observed via scanning electron microscopy and fluorescence staining techniques. Meanwhile, the colony forming counts showed that, compared with the Co-Cr-Mo alloy, the carbon-based nanofilm titanium alloy had fewer bacteria adhered (P < 0.05). After coculture of the two test specimens with rabbit BMSCs, there was no significant difference in cell count, and both cell counts showed no cytotoxicity. In the in vivo experiment of animals, there are relatively fewer giant cells and better histocompatibility in tissues near the carbon-based nanofilm titanium alloy. Conclusion Compared with Co-Cr-Mo alloy, the novel carbon-based nanofilm titanium alloy enjoys stronger in vitro antibacterial activity and better in vivo histocompatibility.

Amination-mediated nano eye-drops with enhanced corneal permeability and effective burst release for acute glaucoma treatment

The development of topical formulations with advanced functions to overcome the poor and sluggish permeability/bioavailability of traditional eye drops into interior of the eye is significantly important for efficient management of acute intraocular diseases. For the first time, we herein exploit the amination level effects of chitosan coatings for facilitating a fast penetration of ceria nanocapsules (NCs) through the corneal barriers followed by triggering an effective burst release of pilocarpine in a controlled manner. Specifically, high amination level can help to improve the permeability of the ceria NCs through corneal cell layers by ∼ 43 folds while endowing the carriers with the most effective burst release performance. In an experimental rabbit model of acute glaucoma, a single dose topical instillation of pilocarpine-loaded chitosan-coated ceria NCs could effectively reduce the extremely high intraocular pressures to normal, prevent damage of endothelium (precluding ∼ 98.7 % cell death), open the angle closure, and inhibit retinal degeneration (impeding ∼ 98 % of retinal axon loss) at 4 h post-treatment. These findings show a great promise for the development of nano eye-drops for efficient management of acute glaucoma and other acute diseases that need prompt treatments.

Evaluation of clinical and histological effects of KGF-2 and NGF on corneal wound healing in an experimental alkali burn rabbit model

Endogenously produced peptide growth factors such as keratinocyte growth factor-2 (KGF-2) and nerve growth factor (NGF) play a key role in the natural corneal wound healing process. However, this self-healing ability of the corneal tissue is often impaired in cases of severe corneal damage, as in corneal alkali injuries. In the present study, we investigated the clinical and histopathological effects of topical recombinant human keratinocyte growth factor-2 and nerve growth factor treatments in a rabbit model of corneal alkali burn. After induction of an alkali burn, 24 rabbits were divided equally into three groups: control group, KGF-2 group, and NGF group. Clinical parameters including epithelial healing, opacification, neovascularization and central corneal thickness were evaluated on the first (D1), seventh (D7) and fourteenth (D14) days after injury. Corneal histology was performed using hematoxylin/eosin (H&E) and Masson's Trichrome stains. Immunohistochemical staining for matrix metalloproteinase-2 (MMP-2), MMP-9 and transforming growth factor-β (TGF-β) was performed. On D14, the percentage of epithelial defect and opacity were significantly less in the KGF-2 and NGF groups compared to the control group (p < 0.05). There was no significant difference between the groups in central corneal thickness. In the evaluation of neovascularization on D14, the NGF group was significantly less vascularized than the control group (p = 0.011). Histological examination showed a significant increase in stromal edema and inflammation in the control group compared to both treatment groups (p < 0.05). There was also a significant difference between the NGF and control groups in histological evaluation of epithelial repair and vascularization (p < 0.05). When immunoreactivity of MMP-2, MMP-9 and TGF-β was examined, there was a significant increase in the control group compared to the NGF group (p < 0.05). Taken together, both NGF and KGF-2 treatments were effective for early re-epithelialization and decrease in inflammation, opacity and neovascularization after corneal alkali burn. The inhibitory effect of NGF treatment on chemical-induced neovascularization was found to be superior to KGF-2 treatment.

Neuroprotective Effects of Dexpanthenol on Rabbit Spinal Cord Ischemia/Reperfusion Injury Model

Dexpanthenol (DXP) reportedly protects tissues against oxidative damage in various inflammation models. This study aimed to evaluate its effects on oxidative stress, inflammation, apoptosis, and neurological recovery in an experimental rabbit spinal cord ischemia/reperfusion injury (SCIRI) model. Rabbits were randomized into 5 groups of 8 animals each: group 1 (control), group 2 (ischemia), group 3 (vehicle), group 4 (methylprednisolone, 30mg/kg), and group 5 (DXP, 500mg/kg). The control group underwent laparotomy only, whereas other groups were subjected to spinal cord ischemia by aortic occlusion (just caudal to the 2 renal arteries) for 20min. After 24h, a modified Tarlov scale was employed to record neurological examination results. Malondialdehyde and caspase-3 levels and catalase and myeloperoxidase activities were analyzed in tissue and serum samples. Xanthine oxidase activity was measured in the serum. Histopathological and ultrastructural evaluations were also performed in the spinal cord. After SCIRI, serum and tissue malondialdehyde and caspase-3 levels and myeloperoxidase and serum xanthine oxidase activities were increased (P<0.05-0.001). However, serum and tissue catalase activity decreased significantly (P<0.001). DXP treatment was associated with lower malondialdehyde and caspase-3 levels and reduced myeloperoxidase and xanthine oxidase activities but increased catalase activity (P<0.05-0.001). Furthermore, DXP was associated with better histopathological, ultrastructural, and neurological outcome scores. This study was the first to evaluate antioxidant, anti-inflammatory, antiapoptotic, and neuroprotective effects of DXP on SCIRI. Further experimental and clinical investigations are warranted to confirm that DXP can be administered to treat SCIRI.

The effect of conjugated linoleic acids on the growth performance, carcase composition and meat quality of fattening rabbits

This experiment was conducted to study the effects of dietary conjugated linoleic acids (CLAs) on the growth performance, fat metabolism, carcase composition and muscle quality of fattening rabbits. A total of 160 Minxinan black rabbits aged 75 days with body weights of 1658.9 ± 188.8 g were randomly divided into 4 groups. They were fed a basic diet supplemented with 0 (control), 0.5%, 1.0%, or 1.5% CLA for 50 days. Dietary CLA reduced the feed intake and serum triglyceride and cholesterol levels. In addition, the crude protein content in rabbit meat was increased, along with the cholesterol and the ether extract levels in the 1.5% depression group. Moreover, the fatty acid composition in rabbit meat was changed, and the content of polyunsaturated fatty acids/monounsaturated fatty acids (PUFAs/MUFAs) increased with the increasing levels of CLA addition. These findings indicate that CLA greatly improved the nutritional value of rabbit meat. From an economic point of view, CLA would normally be included at a concentration of 0.5% in the formulation of feeds for fattening rabbits. HIGHLIGHTS Minxinan black rabbits were fed conjugated linoleic acid (CLA)- supplemented diets for 50 d. CLA decreased the feed intake of experimental rabbits. CLA has significant effects on fat deposition and serum triglyceride and cholesterol levels. CLA greatly improved the nutritional value of rabbit meat. The recommended CLA level is 0.5% for meat rabbits．

Effect of high- intensity extremely low frequency magnetic field on the intermediate stage atherosclerotic plaque remodeling: Monitored by histopathology and color doppler ultrasonography

Background and Aims : The aim of this study was to generate an experimental rabbit common carotid artery model of intermediate stage atherosclerosis and the subsequent, investigating the effect of Extremely Low Frequency (ELF) magnetic field exposure on the foam cells- rich plaque structure in this model.

The correlation between multimodal radiomics and pathology about thermal ablation lesion of rabbit lung VX2 tumor.

ObjectiveTo explore the correlation of CT-MRI pathology with lung tumor ablation lesions by comparing CT, MRI, and pathological performance of rabbit lung VX2 tumor after thermal ablation.MethodsThermal ablation including microwave ablation (MWA) and radiofrequency ablation (RFA) was carried out in 12 experimental rabbits with lung VX2 tumors under CT guidance. CT and MRI performance was observed immediately after ablation, and then the rabbits were killed and pathologically examined. The maximum diameter of tumors on CT before ablation, the central hypointense area on T2-weighted image (T2WI) after ablation, and the central hyperintense area on T1-weighted image (T1WI) after ablation and pathological necrosis were measured. Simultaneously, the maximum diameter of ground-glass opacity (GGO) around the lesion on CT after ablation, the surrounding hyperintense area on T2WI after ablation, the surrounding isointense area on T1WI after ablation, and the pathological ablation area were measured, and then the results were compared and analyzed.ResultsAblation zones showed GGO surrounding the original lesion on CT, with a central hypointense and peripheral hyperintense zone on T2WI as well as a central hyperintense and peripheral isointense zone on T1WI. There was statistical significance in the comparison of the maximum diameter of the tumor before ablation with a central hyperintense zone on T1WI after ablation and pathological necrosis. There was also statistical significance in the comparison of the maximum diameter of GGO around the lesion on CT with the surrounding hyperintense zone on T2WI and isointense on T1WI after ablation and pathological ablation zone. There was only one residual tumor abutting the vessel in the RFA group.ConclusionsMRI manifestations of thermal ablation of VX2 tumors in rabbit lungs have certain characteristics with a strong pathological association. CT combined with MRI multimodal radiomics is expected to provide an effective new method for clinical evaluation of the immediate efficacy of thermal ablation of lung tumors.

A comparative study of a rabbit spinal tuberculosis model constructed by local direct infection via the posterior lateral approach

The present study aims to establish a method of constructing a New Zealand rabbit spinal tuberculosis model by direct local infusion of M. tuberculosis H37Rv strain into the intervertebral disc space through the posterior lateral approach. Sixty-six New Zealand rabbits were pretreated with complete Freund's adjuvant and randomly divided into 4 group: the posterolateral approach model group (Group A, 25), ventral transverse process approach model group (Group B, 25), control group (Group C, 10), and blank group (Group D, 6). In Groups A and B, the bone holes were filled with gelatin sponge after drilling, and the local area was directly infused with 0.1 ml of M. tuberculosis H37Rv strain suspension. In Group C, the gelatin sponge was filled through the posterolateral approach and the local area was infused with 0.1 ml of normal saline suspension. In Group D, No specific treatment was performed. The general conditions of the experimental rabbits in each group were compared to those of a control group; the degree of vertebral body exposure, incision length, and complications of the two methods were compared; and the tuberculosis models were evaluated by imaging, histopathology, and bacterial culture. In Group A, the lateral side of the vertebral body was well exposed, the damage was mild, and no peritoneal rupture or gastrointestinal complications were observed. In Group B, the ventral side of the vertebral body and the intervertebral disc were exposed, and abdominal complications were more likely to occur. The survival rates of the experimental rabbits at 8 weeks after surgery were 92.0% in Group A, 88.00% in Group B, 90.0% in Group C, and 100% in Group D. MRI examinations showed that in Group A, the positive rate of radiographic bone findings was 86.9% at 4 weeks after surgery and 100% at 8 weeks after surgery; in Group B, the positive rate of radiographic bone findings was 78.2% at 4 weeks after surgery and 95.4% at 8 weeks after surgery. There was no significant difference between Groups A and B in the radiographic bone findings rate detected by the same imaging method at the same time point (P > 0.05). Eight weeks after surgery, bone destruction, paravertebral abscess, and caseous necrosis occurred in the vertebral bodies of surviving rabbits in Groups A and B. The BacT/ALERT 3D rapid culture system was used to culture the pus in the lesion, and the results showed that the positive rate of tuberculosis was 52.17% in Group A and 54.54% in Group B, and the difference was not statistically significant (P > 0.05). After pretreatment with complete Freund's adjuvant, direct infusion of the H37Rv strain of M. tuberculosis into the intervertebral disc space of New Zealand rabbits via the posterolateral approach and the ventral transverse process approach can successfully establish rabbit spinal tuberculosis models.

Safety assessment of useing Ba Kich dried extract for 28 days

The &amp;ldquo;Ba kich&amp;rdquo; (Extractum Morinda ofcinalis) dried extract was evaluated for repeated dose toxicity at 28 days in rabbits. In a repeat dose toxicity test, rabbits were given oral solution of dry extract of Ba kich at the level of 0.2 g/kg and 1.0 g/kg for 28 days. Blood samples were taken on days 0, 14 and 28 to check biochemical and hematological parameters. Liver and kidney samples were obtained on day 28 for histopathology. The results of the 28-day repeated dose toxicity assessment showed that the dried Ba kich extract did not have a statistically significant effect on the biochemical and hematological indices, and did not cause damage to the histopathology of the kidney. However, dried Ba kich extract at both dose levels caused fatty degeneration and congestion in the liver of experimental rabbits.

Comparison of the effects of autologous and allogeneic purified platelet-rich plasma on cartilage damage in a rabbit model of knee osteoarthritis.

BackgroundPurified platelet-rich plasma (P-PRP) is gradually being used in the treatment of osteoarthritis (OA), and its sources are mainly divided into autologous and allogeneic blood. However, it is unclear whether autologous PRP is more effective or allogeneic PRP is superior.ObjectiveIn this study, autologous and allogeneic P-PRP was injected at early stage of KOA in rabbits, and then the differences in the efficacy of the two P-PRPs against KOA were compared from several perspectives, including pathological histology and immunohistochemistry.MethodExperimental rabbits were divided into normal group (n = 8), model group (n = 8), autologous P-PRP group (n = 8), and allogeneic P-PRP group (n = 8) using a random number table method. The normal and model groups did not receive any treatment, and the autologous P-PRP and allogeneic P-PRP groups received intra-articular injections of autologous and allogeneic P-PRP, respectively, to observe the changes in the gross specimens of the knee joints of the experimental rabbits in each group. The histopathological changes of chondrocytes were also observed by HE-stained sections of articular cartilage, and the expression of chondrocytes Bone morphogenetic protein-2 (BMP-2) and Sox9 were detected by immunohistochemistry.ResultsCompared with the allogeneic P-PRP group, the differences were statistically significant (P < 0.05) in the gross specimens and pathological histological findings in the autologous PRP group. Immunohistochemical results showed that the expression of BMP-2 and Sox9 was elevated in both the autologous P-PRP group and the allogeneic P-PRP group compared with the model group, and the expression of BMP-2 was higher in the autologous P-PRP group than in the allogeneic P-PRP group, with a statistically significant difference (P < 0.05), while there was no difference in the expression of Sox9 between the two groups (P > 0.05).ConclusionIntra-articular injection of autologous P-PRP activated the expression of BMP-2 and Sox9 in chondrocytes and effectively improved KOA cartilage repair and reduced bone redundancy and joint fluid formation, and its efficacy was superior to that of intra-articular injection of allogeneic P-PRP.

Histopathological characteristics of larynx in hypothyroidism in an experimental rabbit model.

ObjectiveHypothyroidism has a significant effect on the patients' voices. This study evaluated the histopathological characteristics of larynx following hypothyroidism in an experimental rabbit model.MethodsEleven male Dutch rabbits were included. Methimazole‐induced hypothyroidism was done for nine rabbits. The remaining two rabbits were assigned as controls. Six weeks after starting methimazole, a histological examination was performed with parameters of inflammation, ulceration, hemorrhage, and thickness of epithelium, Reinke's space, vocal ligament, thyroarytenoid muscle, collagen deposition, and periodic acid‐Schiff (PAS)‐positive materials, as well as confirmation of hypothyroidism by T4 measurement.ResultsHistologic examination showed a significant thickening of epithelium, Reinke's space, vocal ligament, and collagen PAS‐positive materials deposition in hypothyroid rabbits (p < .05). There was significant reduction in thyroarytenid muscle thickness (p < .05). Inflammation, ulceration, and bleeding were not significantly different between hypothyroid and control rabbits' laryngeal specimens.ConclusionHypothyroidism causes significant changes in the laryngeal tissues. Thickening of epithelium, Reinke's space, vocal ligament, collagen, PAS‐positive materials, and reduced thickness of thyroarytenoid muscle are the major findings of this study.

Genetic analysis of some productive and reproductive traits in New Zealand White rabbits

A total of 625 progenies of New Zealand White rabbits, kept at Sakha Experimental Rabbits, Kafr-El-Sheikh, Government, belonging to Animal production Research Institute, Ministry of Agriculture, Dokki, Cairo, Egypt, during 2010-2017 were used to estimate the genetic parameters and phenotypic and genetic trends for some reproductive and productive traits. Traits studied were litter size at birth (LSB), litter weight at birth (LWB), kit body weight for four weeks (BW1), body weight for 6 weeks (BW2), body weight for 8 weeks (BW3), and marketing weight (BW4). Data were analyzed by using a multivariate animal model. Direct heritability estimates were 0.05, 0.20, 0.23, 0.24, 0.31 and 0.34 for LSB, LWB, BW1, BW2, BW3 and BW4, respectively. All phenotypic and genetic correlations among traits studied were positive and ranged from 0.21 to 0.90 for phenotypic correlations and from 0.04 to 0.78 for genetic correlations. Annual phenotypic changes for LSB, LWB, BW1, BW2, BW3, and BW4 were positive and equal to 0.06, 15.96 g, 18.70 g, 23.15 g, 27.72 g, and 50.69 g, respectively. Also, genetic changes for LSB, LWB, BW4, BW6, BW8, and MW were 0.20, 12.50 g, 14.20 g, 16.25 g, 20.09, and 40.10 g, respectively. The moderate estimates of heritability for body weights confirmed that improvement of these traits can be achieved by genetic selection. Also, positive and significant phenotypic and genetic trends for all traits studied indicated that selection for economic traits is very useful to increase the reproductive and productive performance of rabbits.

Efficiency of Nanohydroxyapatite on Repairing Type II Diabetes Dental Implant-Bone Defect.

The purpose of this study was to see how a nanohydroxyapatite (n-HA) composite polyamide 66 (PA66) affected the repair of bone defects in diabetics with titanium implants, as well as to develop experimental materials for the creation of the interface between bone tissue and titanium implants. Rabbit bone marrow mesenchymal stem cells (MSCs) were isolated using n-HA/PA66 composite material, and the effect of coculture with the material on cell proliferation was analyzed after induction of mineralization. Bone defect models of diabetic experimental rabbits and titanium implants were prepared. Normal rabbits with bone defects were used as control (NC group, N = 8). After the diabetic bone defect (DM group, N = 8) and the implantation of n-HA/PA66 composite material (n-HA/PA66 group, N = 8), the differences in body weight, blood glucose, scanning electron microscopy of the implant-bone interface, bone mineral density, new bone trabecular parameters, histomorphology, and biomechanical properties of the implant-bone interface were compared and analyzed. In vitro test results showed that MSC cell growth could be promoted by mineralization induction, the cell growth condition was good after coculture with n-HA/PA66, and the proliferation activity of MSCs was not affected by the material. In vivo test results showed that the body weight of the DM group and n-HA/PA66 group was considerably inferior to that of the NC group, and the blood glucose was dramatically superior to that of the NC group (P < 0.05). However, the body weight of the n-HA/PA66 group was dramatically superior to that of the DM group (P < 0.05). The bone mineral density, bone volume fraction (BV/TV), bone surface area fraction (BS/BV), bone trabecular thickness (Tb.Th), bone trabecular number (Tb.N), bone trabecular area, and biomechanical properties in the DM group were considerably inferior to those in the NC group and n-HA/PA66 group (P < 0.05). The trabecular space (Tb.Sp) in the NC group and n-HA/PA66 group was dramatically superior to that in the NC group (P < 0.05). The bone mineral density, BV/TV, BS/BV, Tb.Th, Tb.N, trabecular area, and biomechanical properties of the n-HA/PA66 group were dramatically superior to those of the NC group (P < 0.05), while Tb.Sp was considerably inferior to that of the NC group (P < 0.05). These findings showed that the n-HA/PA66 material had good biocompatibility and minimal cytotoxicity, and that filling the space between the surrounding bone and the titanium implant can enhance bone repair. This research paved the way for future research into the tissue-engineered bone in the field of oral surgery.

Changes and Significance of Cytokines in Serum of Rabbits with Acute Pulmonary Embolism

Objective:To observe the changes of cytokines in serum of rabbits with acute pulmonary embolism, and to provide scientific basis for clinical treatment of the disease.Methods: The animal models of pulmonary embolism were established in 26 healthy rabbits by autologous thrombus reinfusion and normal saline injection, and the serum levels of cytokines (TNF-α, IL-1β, HGF) in the two groups were monitored by enzyme-linked immunosorbent assay.Results: The expression levels of serum inflammatory cytokines (TNF-α, IL-1β) increased in both groups of rabbits within 1-3 hours of the acute stage of embolism, but the expression levels of serum inflammatory cytokines in experimental group of rabbits with pulmonary embolism caused by thrombosis increased more obviously；There was no significant change in serum HGF of rabbits before and after embolization in group B. The serum HGF content of experimental rabbits at 1h, 3h, 12h, 24h and 48h after embolization was significantly higher than that before embolization.And in the acute stage of embolism (1-12 hours), it showed a gradual upward trend.Conclusion: The expression level of serum growth factor is different in different acute stages of pulmonary embolism. Detecting serum cytokines in rabbits with acute pulmonary embolism is of great reference significance for improving clinical diagnosis.