Development of a method for determination of progesterone sustained-release formulation in Beagle dog plasma and its pharmacokinetic study / 药学学报

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to determine the plasma concentration of progesterone in Beagle dogs, and apply it to the study of the pharmacokinetics of progesterone sustained-release formulation in Beagle dogs. The plasma samples were processed by protein precipitation method and megestrol acetate was used as an internal standard (IS). The quantitation analysis was performed using multiple-reaction monitoring (MRM) mode at the specific ion transitions of m/z 315.2→97.0 for progesterone and m/z 385.2→267.1 for megestrol acetate (IS) under the positive ion condition. Male Beagle dogs were injected intramuscularly with progesterone sustained-release microspheres and the plasma samples were collected at different time points after administration. The relevant pharmacokinetic parameters were calculated by WinNonlin 8.1 software. A good linearity over the range of 0.1-500.0 ng·mL-1 was yielded by this method. The intra- and inter-day precision (RSD) were all less than 13.25% and the accuracy (RE) was within 8.92%. Stability test showed that progesterone in dog plasma was stable at room temperature for 12 h, up to 60 days at -20 ℃ and after three cycles of freeze-thaw. The recovery of it ranged from 71.43%-77.97%. After intramuscular injection of progesterone sustained-release microspheres in Beagle dogs, tmax was 19.00 ± 25.36 h, Cmax was 137.72 ± 11.59 ng·mL-1, t1/2 was 83.83 ± 26.43 h. The drug was released continuously in vivo and in a continuous absorption process for many times with good sustained-release effect. The method developed in this study is sensitive, rapid and stable. It is suitable for the determination of progesterone plasma concentration in Beagle dogs, and can be applied to the preclinical pharmacokinetic study of progesterone-related formulations. The animal experiment scheme of this study was approved by the Animal Ethics Committee of the Academy of Military Medical Sciences.

Enhanced external counterpulsation improves cardiac function in Beagles after cardiopulmonary resuscitation

The aim of this study was to investigate the influence of enhanced external counterpulsation (EECP) on the cardiac function of beagle dogs after prolonged ventricular fibrillation. Twenty-four adult male beagles were randomly divided into control and EECP groups. Ventricular fibrillation was induced in the animals for 12 min, followed by 2 min of cardiopulmonary resuscitation. They then received EECP therapy for 4 h (EECP group) or not (control group). The hemodynamics was monitored using the PiCCO2 system. Blood gas and hemorheology were assessed at baseline and at 1, 2, and 4 h after return of spontaneous circulation (ROSC). The myocardial blood flow (MBF) was quantified by 18F-flurpiridaz PET myocardial perfusion imaging at baseline and 4 h after ROSC. Survival time of the animals was recorded within 24 h. Ventricular fibrillation was successfully induced in all animals, and they achieved ROSC after cardiopulmonary resuscitation. Survival time of the control group was shorter than that of the EECP group [median of 8 h (min 8 h, max 21 h) vs median of 24 h (min 16 h, max 24 h) (Kaplan Meyer plot analysis, P=0.0152). EECP improved blood gas analysis findings and increased the coronary perfusion pressure and MBF value. EECP also improved the cardiac function of Beagles after ROSC in multiple aspects, significantly increased blood flow velocity, and decreased plasma viscosity, erythrocyte aggregation index, and hematocrit levels. EECP improved the hemodynamics of beagle dogs and increased MBF, subsequently improving cardiac function and ultimately improving the survival time of animals after ROSC.

Safety and effectiveness of hemoperfusion on the removal of uremic toxins in chronic kidney disease / 药学学报

The goal of the present study was to determine the effectiveness and safety of hemoperfusion (HP) in beagle dogs with chronic kidney disease (CKD). The experimental protocol was approved by the Institutional Animal Care and Use Committee of Tianjin Institute of Pharmaceutical Research New Drug Evaluation Research (IACUC2019071501). Twelve CKD model beagles were randomly divided into two groups: a low-frequency treatment group (n = 6) and a high-frequency treatment group (n = 6). The dogs in the high- and low-frequency groups received HP treatment every 3 days and once per week, respectively, for two treatments, with each session lasting 2 h. The test results showed that high-frequency HP treatment significantly decreased the accumulation of toxins in the CKD beagles. Hematology, coagulation function, electrolytes and liver function indicated that the HP treatment was safe. The body index effects were consistent between the low- and high-frequency treatment groups. Therefore, HP treatment once every 3 days was safe at the animal level. Multiple HP treatments every 3 days were more conducive than weekly treatments to the removal of uremic toxins with better prognosis and had no associated safety hazards.

Effect of Cimetidine on the Histopathology and the Expression of SOD2 and GPX1 in Low-dose Accumulative Irradiated Beagle Dogs Spleen / 中国药学杂志

OBJECTIVE: To study the effect of cimetidine on the histopathology and the expression of SOD2, GPX1 gene and protein in low-dose accumulative irradiated Beagle dogs spleen and to investigate the mechanism of cimetidine′s protective effect on low-dose accumulative irradiation. METHODS: Twenty-four male Beagle dogs were divided into six groups: normal control group,model group,positive drug control group and cimetidine groups at the dose of 5.33, 10.67, 21.33 mg•kg-1 respectively. The dogs were irradiated with 60Co-γ-ray at 0.040 8 mGy•min-1 rate for 23 d. Cimitidine was administered intragastrically during irradiation, once a day. Microscope was adopted to observe the pathologic change of spleen and the expression levels of SOD2,GPX1 gene and protein in the spleen tissue of dogs were detected by qRT-PCR and immunohistochemistry techniques. RESULTS: Compared with the model group,cimetidine ameliorated the pathological changes and ultrastructure lesions in the spleen of dogs. Also compared with the model group, the levels of SOD2 and GPX1 protein in cimetidine groups at the dose of 5.33, 10.67, 21.33 mg•kg-1 were higher(P<0.05) and the levels of SOD2 and GPX1 mRNA of the three cimetidine groups were increased significantly(P<0.01). CONCLUSION: Cimetidine can reduce the histological damage. Cimetidine can upregulate the expressions of SOD2 and GPX1 gene and protein and it has good protective effect on the antioxidant system injury.

Comparative Study on the Pharmacokinetics of Ibrutinib and Its Phospholipid Complex in Beagle Dogs / 中国药房

OBJECTIVE： To establish a method for the determination of ibrutinib concentration in Beagle dogs， and to compare the pharmacokinetic difference of ibrutinib and its phospholipid complex in Beagle dogs. METHODS： The male Beagle dogs were randomly divided into Ibrutinib suspension group and Ibrutinib phospholipid complex group （using 0.5％ Carboxymethylcellulose sodium solution and water as solvent， mass concentration of 5 mg/mL）， with 3 dogs in each group. All Beagle dogs were given relevant medicine suspension （15 mg/kg） intragastrically， and 2 mL of blood were collected from the forelimb vein before administration and 0.017， 0.083， 0.25， 0.5， 1， 2， 4， 8 and 12 h after administration. Plasma concentration of ibrutinib was were determined by HPLC. Using tolbutamide as internal standard， the determination was performed on Betasil C18 column with mobile phase consisted of acetonitrile-water （contained 0.5％ triethylamine， pH value adjusted to 3.2 with glacial acetic acid）（45 ∶ 55， V/V） at the flow rate of 1.0 mL/min. The detection wavelength was set at 256 nm， and the column temperature was 25 ℃. The sample size was 20 μL. The pharmacokinetic parameters of Beagle dogs in 2 groups were calculated by using DAS 2.1.1 software. The difference of ibrutinib and its phospholipid complex were investigated by t-test. RESULTS： The linear range of ibrutinib was 5-5 000 ng/mL （r＝0.999 8）； lower limit of quantitation was 5 ng/mL； minimum detection limit was 1.3 ng/mL. RSDs of intra-batch and inter-batch were lower than 10％； the accuracy was 98.81％-106.20％； the extraction method did not influence the determination of the substance to be measured. Pharmacokinetic parameters of Ibrutinib suspension and Ibrutinib phospholipid complex with signal intragastric administration were as follows： tmax were（2.00±0.09） and （0.25±0.03）h； cmax were（610.67±21.36） and （2 308.72±100.41）ng/mL； AUC0-12 h were （4 516.67±383.43） and （9 394.16±874.21）ng·h/mL； AUC0-∞ were （6 174.32±525.27） and （10 717.33±897.62）ng·h/mL，with statistical significance （P＜0.05）. The relative bioavailability of Ibrutinib phospholipid complex was 207.99％. CONCLUSIONS： Established HPLC method is simple， specific and sensitive， and can be used for plasma concentration determination and pharmacokinetic study of ibrutinib. The pharmacokinetic parameters of phospholipid complex prepared from ibrutinib changed significantly， drug absorption is accelerated and bioavailability is improved significantly.

Study on the morphology of micro-implant-bone interface cells and bone histomorphology under different implantation / Estudio sobre la morfología de las células de la interfaz microscópica implante-hueso y la histomorfología ósea bajo diferentes implantaciones

SUMMARY: Micro-implant stability has always been the focus of orthodontic clinical research.In the experiment, the morphological changes of bone tissue around the micro-implants in self-tapping and assisting implantation were investigated to explore the effect of different implantation on the osseointegration of micro-implants in order to provide some theoretical basis for clinical practice. Six adult male Beagle dogs were selected,three implants were implanted into the left and right maxillary bone of Beagle dogs at the 0th, 4th and 6th week, respectively. One side to self-tapping implantation, the opposite side to assisting implantation. At the 8th week of the experiment, the animals were sacrificed and the micro-implant-bone tissue specimens with the healing time of 8w, 4w and 2w were obtained.The specimens were stained with Toluidine Blue (TB) and photographed under 100X, 200X microscope. Morphology of microimplant- bone interface cells was observed under light microscope. In self-tapping group, there were some fibrous tissues surrounding the micro-implants at the 2th week, the formation of osteoblasts and osteoid was observed at the 4th week, the wavy and lamellar bone tissues were seen at the 8th week.In assisting group,more collagen fibers were deposited around the micro-implant at the 2th week, there were a large number of osteoid-like cells, and the collagen was gradually replaced by the bone tissue at the 4th week, the osteoblasts were active and the osteoblasts were linear arrange and form a laminate bone at the 8th week.Whether implanted self-tapping or assisted implantation, micro-implant-bone interface reconstruction can occur. If the clinical need for early loading force, micro-implant try to choose selftapping implantation. By appropriately prolonging the healing time, the initial stability of the micro-implant under assistive implantation can be improved.

RESUMEN: La estabilidad del microimplante siempre ha sido el foco de la investigación clínica en ortodoncia. En este trabajo se investigaron los cambios morfológicos del tejido óseo alrededor de los microimplantes autorroscantes y se ayudó a la implantación para explorar el efecto de diferentes implantes en la osteointegración de microimplantes con el fin de proporcionar alguna base teórica para la práctica clínica. Se seleccionaron seis perros Beagle machos adultos, y se colocaron tres implantes en los huesos maxilares izquierdo y derecho en la 0ª, 4ª y 6ª semana, respectivamente. De un lado se colocó el implante autorroscante, y del otro lado el implante asistido. En la octava semana, se sacrificaron los animales y se obtuvieron las muestras de microimplante-hueso con el tiempo de cicatrización de 8, 4 y 2 semanas. Las muestras fueron teñidas con azul de toluidina (TB) y fotografiadas bajo aumento de 100X, y microscopio de 200X. La morfología de las células de la interfaz microimplante-hueso se observó bajo microscopio óptico. En el grupo autorroscante, había tejido fibroso que rodeaba los microimplantes a la 2ª semana, se observó la formación de osteoblastos y osteoide a la 4ª semana y de tejido óseo ondulado y lamelar a la 8ª semana. En el grupo asistido, se depositaron más fibras de colágeno alrededor del microimplante en la 2ª semana, hubo un gran número de células similares a osteoide, y el colágeno fue reemplazado gradualmente por el tejido óseo en la 4ª semana; los osteoblastos estaban activos y se ubicaron linealmente formando un hueso laminado en la 8ª semana. Ya sea que el implante sea con autoasistencia o con implantación asistida, puede ocurrir la reconstrucción de la interfaz microimplante-hueso. Si existe la necesidad clínica de una fuerza de carga temprana, el microimplante de elección sería la implantación autorroscante. Al prolongar apropiadamente el tiempo de curación, se puede mejorar la estabilidad inicial del microimplante bajo implantación asistida.

Chronic hepatotoxicity evaluation of Chinese medicinal herb Zishen Yutai pill prepared from Polygoni Multiflori Radix preparata in dogs / 中国中药杂志

To study the chronic hepatotoxicity of Chinese medicine Zishen Yutai pill (ZYP) prepared from Polygonum multiflorum with the recommended dosage in normal Beagle dogs. Low, middle and high doses of ZYP (1.5, 3.0, 6.0 g·kg⁻¹; i.e. 3×, 6× and 12× equivalent doses) were given orally to dogs for 39 consecutive weeks. At the same time, the same volume of deionized water was used as the solvent control group, one time a day. The general condition of the animals was observed every day during the period of administration, and the blood was collected before and 13, 26, 39, 43 weeks after administration to detect the biomarkers related to the hepatotoxicity of the dog serum. 2/7, 3/7 and 2/7 animals were dissected after 13, 39, and 43 weeks of administration to observe the pathological changes of the animal organs, weigh the mass of main organs and conduct pathological examination of the liver. As compared to the solvent control group, 11 liver hepatotoxicity traditional biomarkers such as ALT, AST were found no ZYP-related changes at month 3, 6, 9 of the administration and month 1 in recovery period; There was no significant difference in liver viscera index and liver pathology. Therefore, no obvious hepatotoxicity was shown by ZYP administered up to 6.0 g·kg⁻¹ for 9 months in normal dogs at doses of 1.5, 3.0, and 6.0 g·kg⁻¹.

Biomechanical study on nickel-titanium three-dimensional memory alloy mesh combined with autologous bone for living model of canine tibial plateau collapse fracture / 中国修复重建外科杂志

Objective: To evaluate the effect of nickel-titanium three-dimensional memory alloy mesh combined with autologous bone for living model of canine tibial plateau collapse fracture by biomechanical testing. Methods: Sixteen healthy 12-month-old Beagle dogs were randomly divided into 4 group, 4 dogs in each group. The dogs were used to establish the tibial plateau collapse fracture model in groups A, B, and C. Then, the nickel-titanium three-dimensional memory alloy mesh combined with autologous bone (the fibula cortical bone particles), the artificial bone (nano-hydroxyapatite), and autologous fibula cortical bone particles were implanted to repair the bone defects within 4 hours after modeling in groups A, B, and C, respectively; and the plate and screws were fixed outside the bone defects. The dogs were not treated in group D, as normal control. At 5 months after operation, all animals were sacrificed and the tibial specimens were harvested and observed visually. The destructive axial compression experiments were carried out by the biomechanical testing machine. The displacement and the maximum failure load were recorded and the axial stiffness was calculated. Results: All animals stayed alive after operation, and all incisions healed. After 1-3 days of operation, the animals could stand and move, and no obvious limb deformity was found. The articular surfaces of the tibial plateau specimens were completely smooth at 5 months after operation. No obvious articular surface collapse was observed. The displacement and maximum failure load of specimens in groups A and D were significantly higher than those in groups B and C ( P0.05). Conclusion: The nickel-titanium three-dimensional memory alloy mesh combined with autologous bone for subarticular bone defect of tibial plateau in dogs has good biomechanical properties at 5 months after operation, and has better axial stiffness when compared with the artificial bone and autologous bone graft.

Establishment of a penile transplantation model in beagle dogs / 中华男科学杂志

Objective@#To investigate the feasibility of establishing a model of allograft penile transplantation in adult beagle dogs and explore the conditions for constructing a stable animal model of penis transplant.@*METHODS@#Following the principles of similarity, repeatability, feasibility, applicability, and controllability in the construction of experimental animal models, we compared the major anatomic features of the penis of 20 adult beagle dogs with those of 10 adult men. Using microsurgical techniques, we performed cross-transplantation of the penis in the 20 (10 pairs) beagle dogs and observed the survival rate of the transplanted penises by FK506+MMF+MP immune induction. We compared the relevant indexes with those of the 10 cases of microsurgical replantation of the amputated penis.@*RESULTS@#High similarities but no statistically significant differences were observed in penile anatomic features between the 20 beagle dogs and 10 men. All the 10 cases of cross-transplantation of the penis were successfully completed in the 20 beagle dogs, of which the transplanted glans survived with normal micturition in 12 but developed necrosis in the other 8; the success rate of one-time venous anastomosis was 95.0% (38/40) and that of one-time arterial anastomosis was 87.5% (35/40), with an average vascular anastomosis time of (71.0±9.0) minutes, a mean operation time of (133.0±10.3) minutes, and a mean blood loss of (135.8±41.4) ml. In the 10 cases of penile replantation, the success rate of one-time venous anastomosis was 100% (20/20) and that of one-time arterial anastomosis was 90.0% (18/20), with an average vascular anastomosis time of (65.0±7.9) minutes, a mean operation time of (117.4±10.0) minutes, and a mean blood loss of (85.0±10.8) ml. In the 12 cases of replantation of the amputated penis, the success rate of one-time venous anastomosis was 100% (24/24) and that of one-time arterial anastomosis was 95.8% (23/24), with an average vascular anastomosis time of (79.0±17.6) minutes, a mean operation time of (125.0±20.6) minutes, and a mean blood loss of (140.0±44.3) ml. No statistically significant differences were found in the relevant indexes among the three groups.@*CONCLUSIONS@#The anatomic structure of the corpus cavernosum penis of beagle dogs is highly similar to that of men, almost the same in cross-section anatomy. Microsurgical replantation and allograft transplantation of the penis were both successfully performed in beagle dogs, which showed similar operative indexes to those of human penile replantation. The construction of the allograft penile transplantation model in adult beagle dogs is feasible clinically, with the advantages of operability and repeatability.

Pharmacokinetics of the prototype and hydrolyzed carboxylic forms of ginkgolides A, B, and K administered as a ginkgo diterpene lactones meglumine injection in beagle dogs / 中国天然药物

Ginkgo diterpene lactones meglumine injection (GDLI) is a commercially available product used for neuroprotection. However, the pharmacokinetic properties of the prototypes and hydrolyzed carboxylic forms of the primary components in GDLI, i.e., ginkgolide A (GA), ginkgolide B (GB), and ginkgolide K (GK), have never been fully evaluated in beagle dogs. In this work, a simple, sensitive, and reliable method based on ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) was developed, and the prototypes and total amounts of GA, GB, and GK were determined in beagle dog plasma. The plasma concentrations of the hydrolyzed carboxylic forms were calculated by subtracting the prototype concentrations from the total lactone concentrations. For the first time, the pharmacokinetics of GA, GB, and GK were fully assessed in three forms, i.e., the prototypes, the hydrolyzed carboxylic forms, and the total amounts, after intravenous administration of GDLI in beagle dogs. It was shown that ginkgolides primarily existed in the hydrolyzed form in plasma, and the ratio of hydrolysates to prototype forms of GA and GB decreased gradually to a homeostatic ratio. All of the three forms of the three ginkgolides showed linear exposure of AUC to the dosages. GA, GB, and GK showed a constant half-life approximately 2.7, 3.4, and 1.2 h, respectively, which were consistent for the forms at three dose levels (0.3, 1.0, and 3.0 mg·kg) and after a consecutive injection of GDLI for 7 days (1.0 mg·kg).

Main technical points of quarantine inspection of Beagle dogs used for drug GLP experiment / 中国比较医学杂志

The quarantine inspection and acceptance of laboratory animals is an important work, which can protect animals from pollution, occurrence and spread of diseases in the surounding area, and it is the key point to realize the quality standardization of laboratory animals.Beagle dogs are acknowledged widely as specialized laboratory dogs which is widely employed in experiments of drug safety evaluation because of the good genetic stability, environmental adaptability, disease resistance and consistency testing in the experiments.Establishment of standard operating procedures of beagle dog quarantine acceptance check for drug GLP organization tests, refining technical points, strengthen the technical training of quarantine officers, and efforts to improve the level of quarantine are needed to finally ensure the quality of laboratory animals.

Study on the Pharmacokinetics of Arotinoid Ethylester in Beagle Dogs / 中国药房

OBJECTIVE:To study the pharmacokinetic characteristics of arotinoid ethyl ester (RO) in Beagle dogs in vivo. METHODS:18 Beagle dogs were randomly divided into high-dose,medium-dose,low-dose groups (40,20,10 mg/kg),6 in each group. Rats were intragastrically administrated related doses of RO. Blood sample 1 mL was taken after 0.5,1.0,2.0,4.0, 6.0,8.0,12.0,24.0,36.0,48.0,60.0,72.0 h of administration,and plasma was separated. RP-HPLC was used to determine the concentrations of RO and its metabolite arotinoid acetic acid(RA)in plasma. Using DAS 2.0 software for fitting,pharmacokinetic parameters were calculated. RESULTS:Both RO and RA showed a distribution in one-compartment model in dogs in vivo. The cmax of RO high-dose,medium-dose,low-dose groups in dogs in vivo were (0.42 ± 0.87),(0.54 ± 0.09),(0.31 ± 0.05)μg/mL;t1/2z were(1.20±0.33),(1.14±0.45),(1.90±0.65)h;AUC0-72 h were(3.55±0.90),(0.87±0.50),(0.92±0.31)μg·h/mL;and CL/F were(11.99±4.01),(19.87±10.79),(12.29±7.57)L/(kg·h). The cmax of RA high-dose,medium-dose,low-dose groups in dogs in vivo were (32.51 ± 4.04),(19.87 ± 2.78),(16.55 ± 4.06)μg/mL;t1/2z were (7.27 ± 4.20),(7.17 ± 4.20),(10.18 ± 4.01) h;AUC0-72 h were (408.14 ± 96.61),(333.39 ± 61.28),(286.55 ± 30.96)μg·h/mL;and CL/F were (1.30 ± 0.53)、(0.76 ± 0.87)、(0.54±0.10)L/(kg·h). CONCLUSIONS:Orally taking RO is easy to absorb with rapid elimination. Its active metabolite RA has longer accumulation time in vivo.

Therapeutic effects of xylazine and dexmedetomidine in establishing the model of spinal cord inj ury in beagle dogs / 西安交通大学学报(医学版)

ABSTRACT:Objective To observe the anesthetic effects of xylazine and dexmedetomidine in establishing the model of spinal cord injury in beagle dogs.Methods Thirty female beagle dogs were randomly divided into 3 groups with 1 0 in each:xylazine group (group S ), dexmedetomidine group (group D ), and xylazine +dexmedetomidine group (group S+D).Basal anesthesia with ketamine was performed in all the dogs.Then group S was intramuscularly injected with xylazine discontinuously, group D was intravenously injected with dexmedetomidine 2μg/(kg·h)continuously,but group S+D was injected with xylazine and dexmedetomidine in combination.The heart rate (HR),respiratory frequency (RR),Ramsay score and spasm index (SI)were observed at the time of skin incision (T1),after the beginning of the operation 30 min (T2),before the end of the operation 30 min (T3),and the end of the operation(T4);and the usage of anesthetics was recorded.Results Compared with that in groups S and D,the usage of xylazine and dexmedetomidine in group S+D was decreased by 1/2 and 1/4,respectively (P<0.01),but HR and RR did not change significantly;the sedative effect was superior to that in S.No obvious increase in muscular tensility in the foreleg was observed before operation.Conclusion Xylazine and dexmedetomidine used in combination to establish the model of spinal cord injury in beagle dogs have advantages of better sedative effect,less respiratory depression and lower dosage of anesthetic drugs.

Alteration of gene expression profile in Beagle dogs' peripheral blood lymphocytes after acute γ-ray irradiation / 中华放射医学与防护杂志

Objective To investigate the changes of gene expression profile in Beagle dogs' peripheral blood lymphocytes after acute irradiation.Methods Totally 20 male adult Beagle dogs were randomly divided into four groups including non-treatment blank control group and three radiation groups exposed to 0.5,2.0,and 5.0 Gy of γ-rays,respectively.Six hours after radiation,the peripheral blood were collected for lymphocytes isolation.Total RNA was extracted from the lymphocytes and analyzed by microarray hybridization.The differential gene profiles of radiation groups were analyzed by gene ontology (GO) analysis and kyoto encyclopedia of genes and genomes (KEGG) pathways analysis,and the alerted genes were further confirmed by the real time quantitative PCR (qRT-PCR) assay.Results Compared to the blank control group,the expressions of 308 genes in the radiation groups were perturbed over 2-fold of control,including 61 genes up-regulated and 247 genes down-regulated,which were mainly associated with immune response and cancer occurrence.The GO analysis indicated that the differential expressed genes were associated with cell connection,signal transduction,oxidation-reduction reaction and metabolism.The KEGG pathway analysis showed that some physiological and biochemical processes were involved,such as phagocytosis,tumor pathway,p53 signaling pathway,JAK-STAT signal pathway,cell differentiation,and proliferation,oxidative phosphorylation,glycogen dysplasia and other pathways.The microarray data of the alterations of apoptosis enhancing nuclease (AEN) and mitogenactivated protein kinase 13 (MAP3K13) gene expressions were further confirmed by qRT-PCR.Conclusions Exposure to different doses of acute γ-ray irradiation had significant impact on the gene expressions in Beagle dogs' peripheral blood lymphocytes and those differential expressed genes were related to a series of biological processes and pathways including immune response,metabolism and carcinogenesis.

Study on pathomorphological changes of the Iiver in Beagle Dog with spontaneous hepatocirrhosis / 中国比较医学杂志

Objective To study the liver pathomorphological and serum biochemical changes in Beagle dog with spontaneous hepatocirrhosis and establish the backgroud information of experimental animals for GLP .Methods The ALT, AST,TP,ALB, ALP, TBIL, TC, TG and GGT were detected using an automatic biochemical analyzer , and compared the differences of above index between blank control and diseased animal .The histological changes of the liver were observed by optical microscopy.Results Compared with the blank control ,the ALT,AST,ALP,TBIL and GGT of diseased dogs were increased significantly , and the ALB decreased significantly .Compared with normal dogs , the liver cells had nodular regeneration , arranged irregularly and pseudolobule formation .The pseudolobules were packaged with collagen fibers . Conclusion It is suggested that spontaneous lesions in Beagle dogs should be monitored so as to provide appropriate experimental animal histopathologicalbackgroud information for drug safety evaluation .

Advantages and application of telemetry compared with the traditional methods in safety pharmacology / 中国比较医学杂志

Objective To prove the advantages of telemetry by comparing with the traditional methods in safety pharmacology.Methods To monitor continuously the heart rate, respiratory rate, blood pressure and ECG of Beagle dogs by traditional and telemetry methods respectively, analyze and compare the changes between anesthetized and conscious dogs before and after feeding.Results Maintenance of anesthesia changed significantly the heart rate, respiratory rate, blood pressure and QT interval in the ECG of animals.The changes of physiological indicators in 24 h is not obvious in conscious animals, and showed a certain biorhythm.Compared with the conscious animals, the anesthetized dogs’ heart rate was significantly higher, blood pressure increased significantly, QRS and QTcf interval prolonged significantly, respiratory frequency decreased, heart rate increased significantly after feeding, and QTcf interval extended very significantly.Conclusions Traditional methods in safety pharmacology affect animal physiological indicators such as heart rate, blood pressure, respiratory rate and QT interval, which affect the objectivity of drug evaluation.Using conscious animals by telemetry can reduce these errors, however, the interference from outside should be eliminated.

Comparison of human and animal oral microbiota by Illumina sequencing of 16S rRNA tags / 中国比较医学杂志

Objective To provide original reference data for oral ecosystem research, Tibet minipigs, beagle dogs, rhesus monkey, New Zealand white rabbits and Wistar rats were selected to study their respective characteristics of oral microbial mmunities and compared with normal data of humans.Methods Total DNA was extracted from the specimens of oral microbial communities of Tibet minipigs, beagle dogs, rhesus monkey, New Zealand white rabbits and Wistar rats, and used to amplify 16S rRNA V4 fragments with labeled universal primers.The diversity and structure of microbial communities from those animals were compared with that of humans using BIPES and QIIME analysis after Illumina sequencing of 16S rRNA V4 fragments.Results The richness of the oral microbial communities of humans and the five species of laboratory animals was significantly different (P <0.05).Different species of animals have their own unique oral flora, among which the oral flora of the monkey is the most similar to that of humans.Conclusions Among the five species of laboratory animals, the oral microbial communities of rhesus monkeys and humans have highest similarity. Specifically, the Fusobacterium and Porphyromonas levels of rhesus monkeys is most similar to those of humans.Our findings indicate that rhesus monkeys may be suitable animal model for studies of human oral microbial communities.Tibet minipigs may be suitable animal model for Proteobacteria studies, while beagle dogs may be appropriate for modeling of diseases related to Spirochaetes.

Age-associated histological changes of gastric fundal mucosa and ultrastructure of gastric chief cells in human and Beagle dogs / 中华消化杂志

Objective To investigate the effect of aging on gastric pepsinogen secretion through observing histological changes of gastric fundal mucosa and ultrastructure of gastric chief cells in human and Beagle dogs at different ages.Methods Fifty middle-aged and elderly indigestion patients with gastroscopy were selected as study objects and divided into young and middle age group (age 20-59 years,n=19),junior elderly group (age 60-69 years,n=11),middle elderly group (age 70-79 years,n=10),and senior elderly group (no less than 80 years,n=10).In addition,nineteen healthy Beagle dogs were also selected as study objects and divided into young and middle age group (age between 1 to 5 years,n=8),junior elderly group (age six to eight years,n=5),and senior elderly group (no less than 9 years,n=6).The histology and morphology of gastric fundal mucosa of human and Beagle dogs were observed under light microscope.Then the thickness of lamina propria was measured and the number of gastric chief cells was counted.The ultrastructure of gastric chief cells was observed under electron microscope,and the area percentages of secretory granule(also called mucous granule)area in cytoplasm of chief cell was calculated.The data was analyzed by one-way analysis of variance.Results No significant histological and morphological changes of gastric fundal mucosa were observed in human and Beagle dogs at different ages.There was no significant difference in the thickness of lamina propria among different ages in human and Beagle dogs (all P＞0.05).The number of human chief cells of young and middle age group,junior elderly group,middle elderly group and senior elderly group was 71.79±16.85,52.73±16.60,57.10±20.21 and 43.70 ±16.89/high power field (HPF),respectively,which decreased as age increased (F=6.431,P=0.001).The numbers of chief cells of young and middle age group,junior elderly group,and senior elderly group of Beagle dogs were 328.38 ±32.36,341.20 ±42.49 and 225.67 ± 52.19/HPF,respectively,which decreased as age increased (F=13.647,P＜0.01).Aging-related degeneration was founded in ultrastructure of gastric chief cells in human and Beagle dogs including rough endoplasmic reticulum dilation,ribosones missing,secretory granule decreasing and so on.The area percentages of secretory granule area in cytoplasm of human chief cells of young and middle age group,junior elderly group,middle elderly group and senior elderly group were (67.28±3.79)％,(66.88±4.84)％,(65.63±7.10)％ and (56.25±8.47)％,respectively,which decreased as age increased (F=6.069,P=0.002).The area percentages of secretory granule area in cytoplasm of Beagle dogs' chief cells of young and middle age group,junior elderly group,and senior elderly group were (58.83 ± 3.07) ％,(52.34 ± 4.73) ％ and (39.89 ± 4.46) ％,respectively,which decreased as age increased (F=38.837,P＜0.01).Condusion As age increased,the ability of pepsinogen secretion of fundal gland decreased,which may be one of the reasons of functional dyspepsia in the eldly.

Simultaneous determination of metolazone and valsartan in beagle dog plasma using liquid chromatography-tandem mass spectrometry / 军事医学

Objective To develop an LC-MS/MS method for simultaneous determination of metolazone and valsartan in beagle dog plasma.Methods The chromatographic separation was achieved on an Agilent Poroshell 120(2.1 mm ×30 mm × 2.7 μm)analytical column.The multiple reaction monitoring mode operating in positive ion was adopted in MS detection, and precursors to the product ion transitions of m/z 366.2/259, 436.2/291 and 423.4/207 were used to measure metola-zone, valsartan and internal standard ( losartan potassium) .Results The method was linear over the concentration range of 0.5 ng/ml-100 ng/ml for metolazone and 5-5000 ng/ml for valsartan, with the correlation coefficients ( r2 ) of 0.9937 and 0.9939, respectively.The average intra-day precision values ( RSD) were 2.09% -8.85% for metolazone and 2.36%-13.12%for valsartan.The matrix effect values were 87.73%-98.62%for metolazone and 99.03%-137.35%for valsartan.The average recovery was 75.74%-81.82%for metolazone and 83.89%-95.64%for valsartan.Conclu-sion This analytical method for metolazone and valsartan is simple, accurate and sensitive, so it can be used for pharma-cokinetic research of metolazone and valsartan immediate release tablets in beagle dogs.

Pharmacokinetics of acteoside following single dose intragastric and intravenous administrations in dogs / 中国天然药物

Acteoside (verbascoside), a phenylethanoid glycoside widely distributed in various plants, has been shown to have potential activity against Alzheimer's disease, attracting great attentions recently. The present study was designed to develop a selective and sensitive LC-MS/MS method for the determination of acteoside in biological samples and carry our a pharmacokinetic (PK) study in beagle dogs. The PK parameters were calculated using non-compartmental models. Following a single-dose oral administration, acteoside was rapidly absorbed and eliminated, with Tmax being between 30 to 45 min and terminal half-life being about 90 min. The areas under the time-concentration curve (AUC) were 47.28 ± 8.74, 87.86 ± 13.33, and 183.14 ± 28.69 mg · min · L(-1) for oral administration of 10, 20, and 40 mg · kg(-1), respectively, demonstrating that the exposure of acteoside proportionally increased with the dose level. The absolute bioavailability of acteoside was around 4%. For all the PK parameters, there were large variations between individual dogs. In conclusion, the pharmacokinetic characteristics observed in the present study can be of great value to help better understand the pharmacological properties of acteoside and to improve the outcome of its clinical use.