Control Rabbits Research Articles

Intramuscular adipocyte and fatty acid differences between high-fat and control rabbit groups subject to a restricted diet.

Fatty acids of intramuscular fat (IMF) in rabbits can influence meat quality, but it is unclear which fatty acids benefit to human health. A rabbit model of weight gain and weight loss was constructed using two rabbit groups and two growth stages. Stage 1 included control group1 fed a commercial diet(CG1) and experimental group1 fed a high fat diet (EG1). Stage 2 include control group2(CG2) and experimental group2 (EG2) both fed a restricted commercial diet. We detected differences in blood biochemical indicators as well as changes in intramuscular adipose cells and intramuscular fatty acid content in control and experiment groups at two stages. High fat induction can make rabbits become obese, have higher concentrations of glucose (GLU), total cholesterol (TC), triglyceride (TG), low density lipoprotein‐cholesterol (LDL‐C) and free fatty acid (FFA), and lower concentrations of insulin (INS). In addition, a high‐fat diet promotes hypertrophy of precursor adipocytes in femoral muscles. Conversely, a restricted diet causes weight loss, decreases the concentration of TG, FFA, and INS in CG2 and EG2, and increases the deposition of unsaturated fatty acids in the femoral muscle. The content of monounsaturated trans oleic acid (C18:1n‐9T) in EG2 was significantly higher than in CG2, whereas oleic acid (C18:1n‐9C) was significantly lower in EG2 than in CG2. The polyunsaturated fatty acids Linolenate (C18:3 n‐3) and cis‐5,8,11,14,17‐Eicosapentaenoate (C20:5 n‐3) increased in CG2 and EG2. The content of Linoleate (C18:2 n‐6) and γ‐Linolenic acid (C18:3 n‐6) significantly increased in CG2. The content of cis‐11,14‐Eicosatrienoic acid (C20:2) decreased significantly in CG2, but increased significantly in EG2.Thus, a high‐fat diet can increase the formation of unhealthy fatty acids. Conversely, weight loss due to a restricted diet leads to an increase in unsaturated fatty acids in the femoral muscle, indicating that it reduces obesity symptoms and it may improve meat quality in rabbit.

Effects of Rocket Seed Oil, Wheat Germ Oil, and Their Mixture on Growth Performance, Feed Utilization, Digestibility, Redox Status, and Meat Fatty Acid Profile of Growing Rabbits

Vegetable oils are a source of natural antioxidants, including tocopherols, sterols, phenolic compounds, coenzymes, and polyunsaturated fatty acids that provide nutritional value, organoleptic properties, and significantly delay or prevent lipid oxidation. Eighty-four V-line rabbits at 5 weeks of age with an initial body weight (BW) of 535.60 ± 13.48 g were assigned randomly to four experimental groups (seven replicates in each group with three rabbits each). The first group served as a control and received 0.3 mL/kg BW of distilled water (CON), while the second and third groups received 0.3 mL/kg BW of rocket seed oil (RSO) and wheat germ oil (WGO), respectively. The fourth group received a mixture of oils consisting of 0.15 mL of RSO and 0.15 mL of WGO/kg BW (MOs). The experiment lasted 7 weeks. The study investigated the effects of RSO, WGO, and their mixture on growth performance, feed utilization, antioxidant status, and immune response of growing rabbits. The results indicated that the rabbits that were administered orally with RSO and WGO or their mixture had higher (p ≤ 0.05) final BW, weight gain, and average daily gain when compared to the control group. In addition, the feed conversion ratio improved significantly with RSO, WGO, and MOs treatments. Different oil treatments improved nutrient digestibility, nutritive value, and nitrogen balance. Moreover, the rabbits that received RSO, WGO, and their mixture had an improvement the meat fatty acid composition compared to the control rabbits. Oral administration of RSO, WGO, and their mixture significantly improved serum protein fractions, decreased blood urea nitrogen, and had a positive effect on serum total lipids, HDL-c, and LDL-c. Furthermore, the treatments of RSO, WGO, and MOs had a significant improvement in the antioxidative status and immune response.

Sensitive and Specific Immunohistochemistry Protocol for Nucleocapsid Protein from All Common SARS-CoV-2 Virus Strains in Formalin-Fixed, Paraffin Embedded Tissues.

Human coronavirus disease 2019 (COVID-19) is a life-threatening and highly contagious disease caused by coronavirus SARS-CoV-2. Sensitive and specific detection of SARS-CoV-2 viral proteins in tissues and cells of COVID-19 patients will support investigations of the biologic behavior and tissue and cell tropism of this virus. We identified commercially available affinity-purified polyclonal antibodies raised against nucleocapsid and spike proteins of SARS-CoV-2 that provide sensitive and specific detection of the virus by immunohistochemistry in formalin-fixed, paraffin-embedded tissue. Two immunohistochemistry protocols are presented that are mutually validated by the matched detection patterns of the two distinct viral antigens in virus-infected cells within autopsy lung tissue of COVID-19 deceased patients. Levels of nucleocapsid protein in the lungs of COVID-19 decedents, as measured by quantitative histo-cytometry of immunohistochemistry images, showed an excellent log–linear relationship with levels of viral nucleocapsid RNA levels, as measured by qRT-PCR. Importantly, since the nucleocapsid protein sequence is conserved across all known viral strains, the nucleocapsid immunohistochemistry protocol is expected to recognize all common variants of SARS-CoV-2. Negative controls include autopsy lung tissues from patients who died from non-COVID-19 respiratory disease and control rabbit immunoglobulin. Sensitive detection of SARS-CoV-2 in human tissues will provide insights into viral tissue and cell distribution and load in patients with active infection, as well as provide insight into the clearance rate of virus in later COVID-19 disease stages. The protocols are also expected to be readily transferable to detect SARS-CoV-2 proteins in tissues of experimental animal models or animals suspected to serve as viral reservoirs.

IQGAP1: A Potential Therapeutic Target in Acute Myelogenous Leukemia (AML)

Introduction: While AML is phenotypically diverse, genome-wide sequencing studies indicate that the median number of non-synonymous mutations is eight (Science 339,1546, 2013) and that the same pathways are affected in tumors with distinct genetic alterations (Nature 453,1112-1116, 2008). These insights provided the impetus to immunoaffinity purify shared antigenic moieties in human AML and examine their prevalence as well as function.Methods: We employed a previously described method wherein immunization of rabbits with normal human peripheral blood cells whose surface charge had been modified by incubation with fluorodinitrobenzene (FDNB) elicited an antibody response that cross reacted against a broad range of human leukemias (Nature 232,197, 1971). Replicating the described methods WBCs from healthy volunteer donors were suspended at 1x107 cells per ml of PBS and mixed with equal volume of 0.86 mM FDNB for 12 to 15 minutes at room temperature. Three rabbits were immunized with FDNB-treated cells (experimental rabbits). A control rabbit was immunized with sham-treated cells (control rabbit). After complement inactivation, immune sera were absorbed against WBCs from healthy donors. Absorbed immune sera were tested in clinical AML samples by Western blotting. Immunoprecipitation of antigens from whole cell lysates of clinical AML samples was performed using IgG adsorbed on protein A/G Agarose beads. Liquid chromatography and mass spectrometry of the immunoprecipitated material was performed. Fold change in IQGAP1 expression in normal vs AML bone marrow was determined by qRT-PCR and from raw data from Gene Expression Omnibus at the NCBI. IQGAP1 expression was evaluated by immunohistochemistry in cell lines, bone marrow biopsies from AML patients and normal healthy volunteers. IQGAP1 expression was modulated by RNAi and the effect on proliferation and colony formation was measured in cell lines.Results: Western blotting of whole cell lysates of clinical AML samples revealed bands that were recognized by immune serum from experimental rabbits but not the control rabbit. Immuno-precipitation of antigens from whole cell lysates of clinical AML samples revealed the scaffolding protein IQGAP1 as being differentially recognized in independent experiments. We focused on IQGAP1 because it regulates multiple cellular functions including signaling pathways involved in proliferation and transformation and stimulates cell motility and invasion. It is overexpressed in colon cancer, pancreatic cancer, hepatocellular carcinoma, glioma, and other cancers. (Cell Signaling 21,1471-1678, 2009). Western blots of human AML samples probed with anti-IQGAP1 antibody revealed the predicted 190 kDa band, see figure. There was 3 to 9-fold greater expression of IQGAP1 expression in AML versus normal bone marrow observed by qRT-PCR. Analysis of raw data from Gene Expression Omnibus at the NCBI revealed fold change of -3.22636, p-value 2.62 x 10e-7 between normal bone marrow versus AML. Preliminary IHC studies showed strong membranous staining in three leukemia cell lines and bone marrow biopsies from primary AML bone marrow samples but weak partial staining in normal bone marrow. Knocking down expression of IQGAP1 in K562, MV4-11 and THP1 cell lines resulted in significant decrease in proliferation and colony formation as compared to effects of scramble control. Mean and SD of colonies per 2000 cells plated were for K562: naïve 311+/-46, IQGAP1 knockdown 37+/-12, scramble control 127+/-12, MV4-11: naïve 156+/37, IQGAP1 knockdown 55+/- 8, scramble control 147+/-16, and THP1 naïve 232+/-45, IQGAP1 knockdown 17+/-2.9, scramble control 150+/-24.Conclusions: 1. The scaffolding protein IQGAP1is overexpressed in AML compared to normal bone marrow. 2. Knocking down expression of IQGAP1 in AML cell lines resulted in significant decrease in proliferation and colony formation providing proof of concept that IQGAP1 is a potential therapeutic target in AML. [Display omitted] DisclosuresLiesveld:Onconova: Honoraria; Seattle Genetics: Honoraria.

The Influence of Chicken Egg Lysozyme or Zinc-Bacitracin Antibiotic on the Growth Performance, Antibacterial Capacity, Blood Profiles, and Antioxidative Status of Rabbits: A Comparative Study.

Simple SummaryDespite the beneficial role of antibiotics in reducing bacterial infection in rabbits, there is an indirect harmful influence on human health. Thus, replacing antibiotics with friendly alternatives is a suitable strategy to protect the performance and welfare of rabbits. This study aimed at comparing the effects of including dietary egg lysozyme and zinc bacitracin antibiotic (ZnB) on the productivity and health conditions of rabbits. The results show a marked enhancement of the growth performance, antibacterial capacity, blood health, and antioxidative status in rabbits treated with egg lysozyme compared with those treated with ZnB. Thus, using egg lysozyme is recommended to replace the usage of ZnB in rabbit production.Dietary egg lysozyme has beneficial roles in the growth performance and health conditions of animals. The study was performed using 90 multicolored rabbits in three groups (each replicate with thirty rabbits). In the control group, rabbits were fed a diet without zinc bacitracin (ZnB) or egg lysozyme, while the second and third groups were treated with ZnB and lysozyme additive at 100 mg/kg, respectively. After eight weeks, the final weight and body weight gain (BWG) of rabbits fed dietary egg lysozyme and ZnB additives were meaningfully increased (p < 0.05). Nevertheless, the feed conversion ratio (FCR) was markedly decreased by dietary egg lysozyme and ZnB (p < 0.05). Interestingly, dietary egg lysozyme resulted in higher final weight and BWG and lower FCR than rabbits treated with ZnB (p < 0.05). Rabbits treated with egg lysozyme and ZnB additives had markedly lower populations of Clostridium spp. and Escherichia coli (p < 0.05) compared with the control. However, the counts of Lactobacillus and total bacteria were meaningfully increased in the the intestines of rabbits treated with egg lysozyme and ZnB (p < 0.05). The blood total protein and globulin of rabbits fed dietary egg lysozyme and ZnB additives were meaningfully increased (p < 0.05). Blood creatinine was significantly lowered by dietary egg lysozyme compared with the control and ZnB-treated rabbits (p < 0.05). The levels of blood urea, ALT, and AST were markedly lowered (p < 0.05) by dietary egg lysozyme and ZnB. The gene expressions of superoxide dismutase 1 (SOD1) and glutathione peroxidase (GPX) in the liver of rabbits fed dietary egg lysozyme and ZnB additives were markedly upregulated (p < 0.05) compared with the control. Dietary egg lysozyme resulted in higher expression of SOD1 and GPX genes than rabbits treated with ZnB (p < 0.05). In conclusion, the inclusion of egg lysozyme could replace the inclusion of ZnB in the diets of rabbits.

Effect of implants of hydroxyapatite with tricalcium phosphates alloyed with Si on histomorphological and biochemical parameters in cases of bone defects of rabbits

Complex comminuted fractures are accompanied by development of bone defects and loss of reparative potential of the bone tissue in the region of the trauma. This brings the necessity of using implants with optimum osteoconductive and osteointegration properties. The objective of the study was determining the condition of biochemical bone markers and peculiarities of histomorphological changes under the influence of ceramic hydroxyapatite (HA) implants with various physical-chemical properties in the conditions of diaphyseal bone defects in rabbits. We composed control and experimental groups of rabbits with 10 individuals in each with diaphyseal bone defects (3 mm) of the radial bones formed under general anesthesia. In one experimental group, they were filled with granules of hydroxyapatite with α-tricalcium phosphate, and in the second group – with β-tricalcium phosphate, alloyed with Si. In the control rabbits, the defects healed under a blood clot. Blood was analyzed on the 3rd, 7th, 14th, 21st and 42nd days, and as reference we used biochemical parameters of blood of clinically healthy rabbits (n = 10). Bone biopsied materials were taken on days 21–42 under general anesthesia. When using hydroxyapatite with β-tricalcium phosphate, alloyed with Si, we determined early intensification of the levels of nitrogen oxide, angiogenesis and development of bone regenerate in conditions of shortening of inflammatory resorption phase, which was verified according to the level of tartrate-resistant acid phosphatase. According to the level of bone isoenzyme of alkaline phosphatase in the blood serum of animals of the control group, the reparative osteogenesis developed slowly and peaked on day 42, whereas in animals implanted with α-tricalcium phosphate, its development peaked peaked on days 14–42, and when using Si-alloy – on days 7–14. Histomorphologically, on the 21st day, in the case of replacement of bone defect with hydroxyapatite with α-tricalcium phosphate, coarse-fibered type of bone regenerate developed with no dense contact with the elements of the regenerate, while spongy bone trabeculae occurred when hydroxyapatite was applied with β-tricalcium phosphate alloyed with Si, and the control rabbits were observed to be in the stage of cartilaginous callus. On the 42nd day, under the influence of implants of hydroxyapatite with α-tricalcium phosphate, the spongy bone tissue transformed into compact tissue with further mineralization. With implants alloyed with Si, there occurred compact bone tissue, and bone regenerates of the control animals were regions of coarse-fibered and spongy bone tissue without dense contact with the parent bone. This study revealed that hydroxyapatite with β-tricalcium phosphate alloyed with Si had notable osteoinductive and osteointegrating properties, as indicated by early angiogenesis and osteoblast reaction, positive dynamics of the marker biochemical parameters with faster and better development of bone regenerate as spongy bone trabeculae.

Agronomic and In Vitro Quality Evaluation of Dual-Purpose Cereals Clipped at Variable Ages and Their Utilization in Rabbit Feeding

The present study included two experiments; the first one investigated the forage productivity and in vitro quality of a single cut taken at different plant ages (45, 60, and 75 days after sowing—DAS) from four prominent cereal crops, namely, barley, oat, triticale, and ryegrass, grown during two successive winter seasons in Northern Egypt. In addition, the effect of plant age at forage removal on the crop’s regrowth ability and final grain yield was quantified. The second experiment studied the biological in vivo effects of the four crops’ hay cut at the optimum plant age on growth performance, feed utilization, and apparent nutrients’ digestibility of growing rabbits. Despite the progressive increase in the fresh and dry matter yields produced from the four crops with later forage removal and the relatively high quality of the forage removed at 45 DAS, 1st experiment concluded that forage removal at 60 DAS produced a reasonable amount of fresh and dry matter yields with appropriate in vitro quality. Meanwhile, the gain in forage yield, when forage was removed at 60 DAS, was enough to compensate for the consequent reduction in grain yield of the four evaluated crops. The inclusion of variable percentages (0, 10, and 20%) of the four tested crops’ hay, when cut at 60 DAS, in the rabbit’s diet (2nd experiment), resulted in non-significant variations in the rabbit’s final body weight. Meanwhile, regardless of the percentage, the rabbits that were fed on diets including ryegrass hay and barley hay had the highest significant daily weight gain. The best feed conversion ratios were obtained by the rabbits that were fed on diets containing 10 and 20% ryegrass hay as well as 20% triticale hay. The highest dry matter, organic matter, and crude protein digestibility coefficients were obtained by both groups of rabbits that were fed on diets containing 20% ryegrass hay and barley hay. The inclusion of any of the four crops’ hay in the rabbits’ diet resulted in significantly higher digestibility coefficients for all nutrients compared to the control rabbits except for ether extract digestibility. Among the four evaluated crops’ hay, ryegrass hay was found to have an outstanding impact on the productive performance and digestibility of growing rabbits. In growing dual-purpose cereals, it is recommended to cut the crops at 60 DAS to achieve the optimum balance between forage yield and quality on the one hand and final grain yield on the other hand. Moreover, when cut at 60 DAS, the evaluated hay of the four crops was adequate to be included in the rabbits’ diet up to 20% substitution of the commercial fiber sources.

The Role of Instrumentation in the Healing Process of Spinal Tuberculosis: An Experimental Study

Introduction: Tuberculosis is still commonly found in many developing countries. Spinal tuberculosis can cause vertebral deformity and neurological disorders. It was discovered thousands years ago and its management was aimed to eradicate infection and maintain the integrity of the vertebrae. Previously, the management of spinal TB was using drugs and external stabilization. Surgical techniques were developed afterwards to clean the infected vertebral segment. Because of the vertebral deformity remained inevitable and had impacts on neurological disorders, new paradigm had been developed by using instrumentation to stabilize the deformity of infected vertebral segment and to restore and maintain neurological function. TGF-β has a major role in angiogenesis in bone healing process. Spinal TB instrumentation uses metal devices composed of ions and particles that can interact each other so it could produce physical and chemical energy that is transmitted to the vertebrae. The energy is expected to enhance the biomolecular and biocellular activity of the body's immune cells so the healing process could be better.&#x0D; Methods: An experimental study was carried out on New Zealand Rabbits which were given TB H37Rv strain infection in the vertebral body. Samples were divided into five groups namely control rabbits, infected rabbits without intervention, infected rabbits treated by instrumentation, infected rabbits given anti-tuberculosis drugs and infected rabbits treated by instrumentation and given drugs. Then the cytokine levels of TGF-β were evaluated and compared.&#x0D; Results: The results showed a significant TGF- β level increase in infected rabbits given drugs alone and instrumentation alone compared to infected rabbits without intervention. There was a significant TGF- β increase in infected rabbits given drugs and treated by instrumentation compared to control rabbits and rabbits who received drugs only.&#x0D; Conclusions: Instrumentation can improve the healing process in spinal tuberculosis by increasing the body's cytokine levels.

In Vivo Molecular K-Edge Imaging of Atherosclerotic Plaque Using Photon-counting CT.

BackgroundMacrophage burden is a major factor in the risk of atherosclerotic plaque rupture, and its evaluation remains challenging with molecular noninvasive imaging approaches. Photon-counting CT (PCCT) with k-edge imaging aims to allow for the specific detection of macrophages using gold nanoparticles.PurposeTo perform k-edge imaging in combination with gold nanoparticles to detect and quantify the macrophage burden within the atherosclerotic aortas of rabbits.Materials and MethodsAtherosclerotic and control New Zealand white rabbits were imaged before and at several time points up to 2 days after intravenous injection of gold nanoparticles (3.5 mL/kg, 65 mg gold per milliliter). Aortic CT angiography was performed at the end of the follow-up using an intravenous injection of an iodinated contrast material. Gold k-edge and conventional CT images were reconstructed for qualitative and quantitative assessment of the macrophage burden. PCCT imaging results were compared with findings at histologic examination, quantitative histomorphometry, transmission electron microscopy, and quantitative inductively coupled plasma optical emission spectrometry. Pearson correlations between the macrophage area measured in immunostained sections and the concentration of gold and attenuation measured in the corresponding PCCT sections were calculated.ResultsSeven rabbits with atherosclerosis and four control rabbits without atherosclerosis were analyzed. In atherosclerotic rabbits, calcifications were observed along the aortic wall before injection. At 2 days after injection of gold nanoparticles, only gold k-edge images allowed for the distinction of plaque enhancement within calcifications and for lumen enhancement during angiography. A good correlation was observed between the gold concentration measured within the wall and the macrophage area in 35 plaques (five per rabbit) (r = 0.82; 95% CI: 0.67, 0.91; P < .001), which was higher than that observed on conventional CT images (r = 0.41; 95% CI: 0.09, 0.65; P = .01). Transmission electron microscopy and inductively coupled plasma optical emission spectrometry analyses confirmed the gold k-edge imaging findings.ConclusionPhoton-counting CT with gold nanoparticles allowed for the noninvasive evaluation of both molecular and anatomic information in vivo in rabbits with atherosclerotic plaques.Published under a CC BY 4.0 license.Online supplemental material is available for this article.See also the editorial by Leiner in this issue.

Feasibility studies of intraocular use of gelatin methacryloyl hydrogel to patch retinal tears

AbsractWe engineered gelatin methacryloyl (GelMA) to be a sealant that can patch retinal tears and verified its biocompatibility in rabbit eyes. We compared adhesion, stability at 37°C, degradation time, swelling ratio, photo‐crosslinking time, pH, and physical conditions before photo‐crosslinking GelMA at 37°C with different methacrylic anhydride (MA) degrees of substitution (25, 50, and 75%) and concentrations (10, 20, and 30%). We injected 0.1 ml GelMA prepolymer into the vitreous cavity in study rabbits (n = 6) and 0.1 ml normal saline into control rabbits (n = 6), and performed clinical and histological examinations. GelMA hydrogel with a 75% degree of substitution and 20% concentration (75/20) exhibited stronger adhesion and stable properties during the first 2 weeks. It can be injected with a 25‐gauge needle at 37°C before photo‐crosslinking. Degradation time was acceptable, the swelling ratio was low, photo‐crosslinking time was short, and the pH was stable. No significant inflammation or other complications occurred, and intraocular pressure remained within a normal range of 16–20 mmHg after surgery. Histological examination revealed no damage to the retinal layers. GelMA (75/20) was the most suitable formulation to close retinal tears, and it exhibited satisfactory intraocular biocompatibility. GelMA can be used as a patch to seal retinal tears during vitrectomy for rhegmatogenous retinal detachment.

A fast and high-sensitivity liquid chromatography-tandem mass spectrometry method combined with in vivo microdialysis for quantification of meropenem in rabbits with sepsis under the simultaneous infusion of total parenteral nutrition: Application to a pharmacokinetic study.

A fast and high-sensitivity liquid chromatography-tandem mass spectrometry (LC-MS/MS) method assisted by microdialysis was established for the determination of meropenem in total parenteral nutrition (TPN) infused plasma. A 10-times dilution was arranged for sample preparation to overcome the severe matrix effect caused by the high salt content in dialysate and complex composition of TPN. This quantification method was proved to be satisfied in selectivity, accuracy, precision, linearity (R2 > 0.998), recovery, matrix effect and stability. In the optimized conditions, the calibration curve range was set from 2 to 2000 ng/ml. This validated method was applied to pharmacokinetics study of meropenem in rabbits with sepsis (induced by cecal ligation and punctures) under simultaneous infusion of TPN to simulate the clinical practice. The results demonstrated that the LC-MS/MS method assisted by microdialysis can be used successfully for the determination of meropenem in TPN-infused plasma. Moreover, the area under the curve and the maximum concentrations in the plasma of meropenem in control rabbits were significantly smaller (P < 0.05), while clearance and distribution volumes were significantly greater (P < 0.05) than in those with sepsis. It could be speculated that drug monitoring in patients with sepsis may be necessary.

Toll-like receptor 4 activation modulates pericardium-myocardium interactions in lipopolysaccharide-induced atrial arrhythmogenesis.

Inflammation plays a role in the pathogenesis of atrial fibrillation (AF). Pericarditis enhanced atrial arrhythmogenesis, but the role of the pericardium remains unclear in AF. Activation of the toll-like receptor 4 (TLR4) by binding to lipopolysaccharide (LPS) promotes cardiac electrical remodelling. In this study, we hypothesized that pericarditis may induce atrial arrhythmogenesis via pericardium-myocardium interactions by TLR4 signalling. Pericarditis was induced in rabbits by injecting LPS (1-2 mg/kg) into the pericardium. Conventional microelectrodes were used to record the action potentials of left atrial (LA) posterior walls (LAPWs) and LA appendages (LAAs) with and without attached pericardium in the control or pericarditis-induced rabbits. Cytokine array was used to measure the expression levels of proinflammatory cytokines in control and LPS-treated pericardium. Compared with the controls, the LPS-treated pericardium had higher expressions of IL-1α, IL-8, and MIP-1β. Rapid atrial pacing-induced burst firing in LPS-treated LAPWs and LAAs, and in control LAPWs (but not in LAAs). The incidence of pacing-induced spontaneous activity and burst firing was increased by LPS-treated pericardium but was attenuated by the control pericardium. Moreover, burst firing induced by LPS-treated pericardium was blocked upon administration of the TLR4 inhibitor, TAK-242 (100 ng/mL), ryanodine receptor inhibitor (ryanodine, 3 μM), or calmodulin kinase II inhibitor (KN-93, 1 μM). Healthy and inflamed pericardium differently modulate LPS-induced atrial arrhythmogenesis. Targeting pericardium via TLR4 signalling may be a novel therapeutic strategy for AF.

Targeted Delivery of Salusin-α Into Rabbit Carotid Arterial Endothelium Using SonoVue.

ObjectivesA new method based on the adhesion of SonoVue to plasmids was assessed to achieve targeted gene delivery into the vascular endothelium.MethodspEGFP‐Salusin‐α and pcDNA3.1‐Salusin‐α plasmids were transfected into the arterial endothelium of different rabbit groups. Western blotting was performed to analyze the expression of EGFP and salusin‐α in the common carotid arteries of rabbits from different groups, and ELISA was performed to detect plasma salusin‐α levels in rabbits from each group; simultaneously, blood parameters of different groups of rabbits were measured.ResultsGreen fluorescence was observed in the right common carotid artery of rabbits transfected with pEGFP‐Salusin‐α, but not in the endothelial cells of not‐transfected control rabbits. The expression of salusin‐α in the transfected animals was higher than that in the control not‐transfected animals (P < .05). In rabbits transfected with pcDNA3.1‐Salusin‐α plasmid, salusin‐α expression was higher than in the not‐transfected control animals (P < .05). However, there was no significant difference in plasma salusin‐α levels between transfected animals and controls (P > .05). Blood parameters were also measured in both groups.ConclusionsOur data confirm the establishment of a new method using SonoVue for targeted gene delivery into the arterial endothelium. Our study outcomes propose a new method of intervention in atherosclerosis and a new tool for targeted gene delivery.

Influence of Streptomyces levoris CNMN-Ac-01 on meat productivity and chemical parameters of rabbit meat

The purpose of the work was to evaluate the influence of biomass of Streptomyces levoris CNMN-Ac-01 added to fodder on meat productivity and chemical composition of rabbit meat. The experimental and control groups of animals (each one consisting of 5 rabbits) were formed according to analogous principles of age, sex (only females), body weight, mode of maintenance and feeding. The age of rabbits used for the experiment was 45 days. The control rabbits were fed with granulated fodder produced according to the recipe developed in the laboratory of Nutrition and Forage Technologies. The rabbits in experimental group were fed with the same granulated fodder supplemented with 0.1% biomass of Streptomyces levoris CNMN-Ac-01. The results of the chemical analyzes of the used fodder indicated that the elaborated fodder composition provide rabbits with all necessaries for their vital activity, where as added biomass of Streptomyces levoris CNMN-Ac-01 do not significantly affect its chemical composition. The increase of the protein content by 0.20% and water by 1.15% were observed in meat of experimental rabbits where the content of fat was decreased for 0.71% in comparison to those of the experimental group. The supplementing of streptomycete biomass in granulated fodder had an essential effect on the weight gain of rabbits and improves the bone and meat ratio in the carcass.

Transplantation of human induced pluripotent stem cell-derived neural crest cells for corneal endothelial regeneration

BackgroundThe corneal endothelium maintains corneal hydration through the barrier and pump function, while its dysfunction may cause corneal edema and vision reduction. Considering its development from neural crest cells (NCCs), here we investigated the efficacy of the human induced pluripotent stem cell (hiPSC)-derived NCCs for corneal endothelial regeneration in rabbits.MethodsDirected differentiation of hiPSC-derived NCCs was achieved using the chemically defined medium containing GSK-3 inhibitor and TGF-β inhibitor. The differentiated cells were characterized by immunofluorescence staining, FACS analysis, and in vitro multi-lineage differentiation capacity. For in vivo functional evaluation, 1.0 × 106 hiPSC-derived NCCs or NIH-3 T3 fibroblasts (as control) combined with 100 μM Y-27632 were intracamerally injected into the anterior chamber of rabbits following removal of corneal endothelium. Rabbit corneal thickness and phenotype changes of the transplanted cells were examined at 7 and 14 days with handy pachymeter, dual-immunofluorescence staining, and quantitative RT-PCR.ResultsThe hiPSC-derived NCCs were differentiated homogenously through 7 days of induction and exhibited multi-lineage differentiation capacity into peripheral neurons, mesenchymal stem cells, and corneal keratocytes. After 7 days of intracameral injection in rabbit, the hiPSC-derived NCCs led to a gradual recovery of normal corneal thickness and clarity, when comparing to control rabbit with fibroblasts injection. However, the recovery efficacy after 14 days deteriorated and caused the reappearance of corneal edema. Mechanistically, the transplanted cells exhibited the impaired maturation, cellular senescence, and endothelial-mesenchymal transition (EnMT) after the early stage of the in vivo directional differentiation.ConclusionsTransplantation of the hiPSC-derived NCCs rapidly restored rabbit corneal thickness and clarity. However, the long-term recovery efficacy was impaired by the improper maturation, senescence, and EnMT of the transplanted cells.

Managing ecosystems in a sea of uncertainty: invasive species management and assisted colonizations.

Managing ecosystems in the face of complex species interactions, and the associated uncertainty, presents a considerable ecological challenge. Altering those interactions via actions such as invasive species management or conservation translocations can result in unintended consequences, supporting the need to be able to make more informed decisions in the face of this uncertainty. We demonstrate the utility of ecosystem models to reduce uncertainty and inform future ecosystem management. We use Phillip Island, Australia, as a case study to investigate the impacts of two invasive species management options and consider whether a critically endangered mammal is likely to establish a population in the presence of invasive species. Qualitative models are used to determine the effects of apex predator removal (feral cats) and invasive prey removal (rabbits, rats, and mice). We extend this approach using Ensemble Ecosystem Models to consider how suppression, rather than eradication influences the species community; and consider whether an introduction of the critically endangered eastern barred bandicoot is likely to be successful in the presence of invasive species. Our analysis revealed the potential for unintended outcomes associated with feral cat control operations, with rats and rabbits expected to increase in abundance. A strategy based on managing prey species appeared to have the most ecosystem-wide benefits, with rodent control showing more favorable responses than a rabbit control strategy. Eastern barred bandicoots were predicted to persist under all feral cat control levels (including no control). Managing ecosystems is a complex and imprecise process. However, qualitative modeling and ensemble ecosystem modeling address uncertainty and are capable of improving and optimizing management practices. Our analysis shows that the best conservation outcomes may not always be associated with the top-down control of apex predators, and land managers should think more broadly in relation to managing bottom-up processes as well. Challenges faced in continuing to conserve biodiversity mean new, bolder, conservation actions are needed. We suggest that endangered species are capable of surviving in the presence of feral cats, potentially opening the door for more conservation translocations.

Electrophysiological and Pathological Impact of Medium-Dose External Carbon Ion and Proton Beam Radiation on the Left Ventricle in an Animal Model.

BackgroundMedium‐dose (25 gray) x‐ray radiation therapy has recently been performed on patients with refractory ventricular tachyarrhythmias. Unlike x‐ray, carbon ion and proton beam radiation can deliver most of their energy to the target tissues. This study investigated the electrophysiological and pathological changes caused by medium‐dose carbon ion and proton beam radiation in the left ventricle (LV).Methods and ResultsExternal beam radiation in the whole LV was performed in 32 rabbits. A total of 9 rabbits were not irradiated (control). At the 3‐month or 6‐month follow‐up, the animals underwent an open‐chest electrophysiological study and were euthanized for histological analyses. No acute death occurred. Significant LV dysfunction was not seen. The surface ECG revealed a significant reduction in the P and QRS wave voltages in the radiation groups. The electrophysiological study showed that the local conduction times in each LV site were significantly longer and that the local LV bipolar voltages were significantly lower in the radiation groups than in the control rabbits. Histologically, apoptosis, fibrotic changes, and a decrease in the expression of the connexin 43 protein were seen in the LV myocardium. These changes were obvious at 3 months, and the effects were sustained 6 months after radiation. No histological changes were seen in the coronary artery and esophagus, but partial radiation pneumonitis was observed.ConclusionsMedium‐dose carbon ion and proton beam radiation in the whole LV resulted in a significant electrophysiological disturbance and pathological changes in the myocardium. Radiation of the arrhythmogenic substrate would modify the electrical status and potentially induce the antiarrhythmic effect.

Antioxidant and anti-apoptotic potential of whole-pomegranate extract promoted growth performance, physiological homeostasis, and meat quality of V-line rabbits under hot summer conditions

The present research evaluated the antioxidant and anti-apoptotic potentialities of whole-pomegranate extract (WPE) on the performance, hemato-biochemical indices, carcass yield, and meat quality of male V-line rabbits under hot summer conditions. For this purpose, 48 weaned, 4-week-old male V-line rabbits were randomly divided into groups of 12 as: group 1 was fed a basal diet (control); and groups 2, 3, and 4 were fed a basal diet supplemented with 1,000 mg/kg (T1), 1,250 mg/kg (T2), and 1,500 mg/kg (T3) of WPE, respectively, for 60 days during the summer. Chromatographic analysis of WPE indicated that syringic acid (SA), vanillic acid and caffeic acid were the predominant flavonoids, while Eicosapentaenoic acid (EPA) was the major quantified fatty acid. Concerning growth performance, WPE supplementation increased the final rabbit weight gain compared with that of the control. Meat-quality traits that were significantly affected (P < 0.05) by dietary WPE supplementation were tenderness and yellowness. Physiologically, WPE induced high levels of dose-dependent hemoglobin, superoxide dismutase (SOD), total antioxidant capacity (TAC), and high-density lipoprotein cholesterol. In addition, WPE significantly restricted heat oxidative stress indicators, namely malondialdehyde, aspartate aminotransferase (AST), alanine aminotransferase (ALT), total cholesterol, triacylglycerol, and white blood cells, which were adversely affected by summer heat stress in the control rabbits (P < 0.05). However, there were no significant variations (P> 0.05) in the catalase and creatinine levels between the WPE-treated groups and the control. Genetically, WPE increased the expressions of the antioxidant glutathione peroxidase (GPX1) and anti-apoptotic B-cell lymphoma 2 (Bcl-2) genes and inhibited the expressions of Bcl-2 Associated X-protein (Bax) and caspase-3 genes. The LibDock ligand-protein modelling suggested that the three biological candidates most likely modulated by SA supplementation at the molecular level were catalase enzyme, glutathione peroxidase (GPX1), and caspase genes. Collectively, rabbit supplementation with 1,250 or 1,500 mg/kg WPE potentially protected V-line rabbits from adverse effects of chronic heat stress by improving endogenous and genetic expressions of antioxidant and anti-apoptotic enzymes and genes.

Serum Glucose, Bilirubin, Liver Enzymes, Renal Parameters, Protein Profile and Some Electrolytes in Adult Male Domestic Rabbits Intoxicated with Chlorpyrifos

Administration of 1/10 LD₅₀ chlorpyrifos (33.3 mg kg^-1 body weight) provoked a general increase in serum glucose and bilirubin compared to control rabbits, with maximum % differences of 27.2 and 15.2%, and p-values of 0.002 and 0.044, respectively. Alanine amino transferase (ALT), aspartate amino transferase (AST), gamma-glutamyl transferase (γ-GT), and alkaline phosphatase (ALP) showed significant elevation registering maximum % differences of 30.2, 37.1, 29.4 and 26.8%, and p-values of 0.007, 0.003, 0.008 and 0.002, respectively.

Titania-Containing Bone Cement Shows Excellent Osteoconductivity in a Synovial Fluid Environment and Bone-Bonding Strength in Osteoporosis.

Titania bone cement (TBC) reportedly has excellent in vivo bioactivity, yet its osteoconductivity in synovial fluid environments and bone-bonding ability in osteoporosis have not previously been investigated. We aimed to compare the osteoconductivity of two types of cement in a synovial fluid environment and determine their bone-bonding ability in osteoporosis. We implanted TBC and commercial polymethylmethacrylate bone cement (PBC) into rabbit femoral condyles and exposed them to synovial fluid pressure. Rabbits were then euthanized at 6, 12, and 26 weeks, and affinity indices were measured to evaluate osteoconductivity. We generated a rabbit model of osteoporosis through bilateral ovariectomy (OVX) and an 8-week treatment with methylprednisolone sodium succinate (PSL). Pre-hardened TBC and PBC were implanted into the femoral diaphysis of the rabbits in the sham control and OVX + PSL groups. Affinity indices were significantly higher for TBC than for PBC at 12 weeks (40.9 ± 16.8% versus 24.5 ± 9.02%) and 26 weeks (40.2 ± 12.7% versus 21.2 ± 14.2%). The interfacial shear strength was significantly higher for TBC than for PBC at 6 weeks (3.69 ± 1.89 N/mm2 versus 1.71 ± 1.23 N/mm2) in the OVX + PSL group. These results indicate that TBC is a promising bioactive bone cement for prosthesis fixation in total knee arthroplasty, especially for osteoporosis patients.