Hematological Changes after Caprine Demineralized Bone Matrix Implantation in Ulnar Critical Defect of Rabbit Model / Alterações hematológicas após implante de matriz óssea desmineralizada caprina em modelo de defeito ulnar crítico em coelhos

Abstract Objective Several animal models have been used in fracture healing and bone graft studies, but hematological responses are seldom reported. Therefore, the present study reported the hematological changes observed in rabbits that underwent xenografting of caprine demineralized bone matrix (CDBM). Method Twenty-four (24) male rabbits (2.5 0.5kg) were acquired for the purpose of this study and were randomly assigned to three groups: autologous bone graft (ABG), unfilled (NC), and caprine demineralized bone matrix (CDBM). Blood samples were collected through cardiac puncture under xylazine-ketamine anesthesia on day 0 (baseline), and on days 28 and 56 postsurgery and were analyzed manually within 2hours of collection. Statistical analysis was performed using a two-way analysis of variance (ANOVA) with repeated measures, and a p-value< 0.05 was considered significant. Result There was an overall significant difference in the values of total white blood cell count (p» 0.0043), neutrophil count (p< 0.0001), monocyte count (p» 0.0184), red blood cell count (p» 0.003), hemoglobin concentration (p< 0.0001) and packed cell volume (p< 0.0001) across the days and the treatment groups. There was, however, no overall significant difference in lymphocyte count (p» 0.4923), basophil count (p» 0.4183), and eosinophil count (0.4806) within days. Conclusion Response to CDBM grafting in rabbits could, therefore, be said to be characterized by marked leukocytosis with neutrophilia, lymphocytosis, and monocytosis by day 28 of postgrafting. This could form the basis with which hematology can be used to monitor body response of bone graft animal models.

Resumo Objetivo Diversos modelos animais têm sido usados em estudos sobre enxertos ósseos e o tratamento de fraturas, mas as respostas hematológicas são raramente relatadas. Este estudo descreveu as alterações hematológicas observadas em coelhos submetidos a xenoenxertos de matriz óssea desmineralizada caprina (MODC). Métodos Vinte e quatro (24) coelhos machos (2,5 0,5 kg) foram adquiridos para este estudo e divididos aleatoriamente em três grupos: enxerto ósseo autólogo (EOA); controle negativo sem preenchimento (SP) e matriz óssea desmineralizada caprina (MODC). Amostras de sangue foram coletadas por punção cardíaca sob anestesia com xilazina-quetamina no dia 0 (para estabelecimento dos valores basais) e aos dias 28 e 56 após a cirurgia; essas amostras foram submetidas à análise manual em até 2 horas após a coleta. A análise estatística foi composta por análise de variância (ANOVA) de dois fatores com medidas repetidas, e o valor de p< 0,05 foi considerado significativo. Resultados Houve uma diferença geral significativa nos números de leucócitos totais (p» 0,0043), neutrófilos (p< 0,0001), monócitos (p» 0,0184) e hemácias (p» 0,003), na concentração de hemoglobina (p< 0,0001) e no hematócrito (p< 0,0001) ao longo dos dias e entre os grupos de tratamento. No entanto, não houve diferença global significativa no número de linfócitos (p» 0,4923), basófilos (p» 0,4183) e eosinófilos (p» 0,4806) entre os dias. Conclusão A resposta ao enxerto de MODC em coelhos é, portanto, caracterizada por leucocitose intensa com neutrofilia, linfocitose e monocitose no 28° dia após o procedimento. Esses dados podem basear a utilização da hematologia no monitoramento da resposta corporal em modelos animais de enxerto ósseo.

Application progress of experimental animal model of humanized fecal microbiota transplantation in depression research / 药学学报

The incidence rate of depression is increasing, but its pathological mechanism is still unknown. More evidence shows that the occurrence and development of depression is closely related to the changes of gut microbiome. However, due to the huge differences in bacterial composition among individuals caused by different environmental factors, researchers usually need a large number of samples to get reliable results. Experimental animal models play an important role in the pathogenesis of diseases and the mechanism of drug action because of their highly consistent background, controllable experimental environment, and the characteristics of artificial intervention. Therefore, the selection of appropriate experimental animal models can not only simulate the clinical symptoms of human depression, but also reveal the causal relationship between clinical characteristics and gut microbiome changes. In this review, the development and application of fecal microbiota transplantation technology, the close relationship between flora and depression, the application of humanized fecal microbiota transplantation experimental animal model in the study of depression, as well as the preparation methods and key technologies of humanized fecal microbiota were summarized, which provided a reference for the research on the pathogenesis of depression and the mechanism of antidepressant drugs of humanized fecal microbiota transplantation experimental animal model. This review provides a reference for the reasonable application of this aspect.

The novel model: Experimental optical coherence tomography–guided anterior segment imaging chick embryo model

Purpose: The aim of this study was to present an experimental optical coherence tomography (OCT)–guided anterior segment (AS) imaging chick embryo model. Through this model, we aimed to reveal similarities and differences between human cornea, AS tissues, and chick embryo tissues by quantitative image analysis. Methods: Ex vivo, the chick embryos' globes were determined by detailed AS camera of spectral-domain (SD)-OCT in 10 fertilized specific pathogen-free eggs on the 20th day. Quantitative image analysis of anterior chamber tissues was performed with SD-OCT in detail. After imaging, cross sections of the chick embryo globes containing cornea with anterior chamber were histologically examined and compared with human tissues. The similarities of our model with data in the human cornea and AS studies in the literature were compared. Results: SD-OCT imaging was able to successfully delineate the AS tissues of chick embryos such as the cornea, iris, lens, pupil, conjunctiva, ciliary body, anterior chamber, and lens. Quantitative semi-automated measurements showed the following: mean central corneal thickness: 213.4 ± 7.05 ?m (197–223 ?m), mean anterior chamber depth: 878.9 ± 41.74 (804–919 ?m), mean anterior chamber area: 2.43 ± 0.16 mm2 (2.17–2.73 mm2), mean corneoscleral junction (limbal) thickness: 322.8 ± 20.05 ?m (289–360 ?m), and mean iris thickness: 230.4 ± 13.27 ?m (203–245 ?m). In addition, detailed histological comparisons of the AS tissues with human tissues were evaluated to be very similar. Conclusion: In conclusion, this chick embryo model mimics human tissues and it can be considered as a platform for the study of teratogen-induced malformations and AS dysgenesis during gestation of AS tissues. In addition, this study demonstrates the feasibility of SD-OCT in the quantitative assessment of AS structures in chick embryo model.

Research progress in experimental animal models of breast cancer / 中国比较医学杂志

Breast cancer is the most common spontaneous malignancy in women, causing a serious threat to women's health. Experimental animal models have been important research tools in bringing insights into the related mechanisms of breast cancer, as well as in delivering improved therapies for the disease. To reveal the pathogenesis of various breast cancers and facilitate the development of new drugs,ideal animal models of breast cancer should share some common tumor molecular characteristics and biological behavior with that of human breast cancer. In this review,five types of experimental animal breast cancer models were included, which may provide a basis for research on diagnosis and treatment of human breast cancer.

Effects of acute normovolemic hemodilution on healing of gastric anastomosis in rats

PURPOSE: Acute normovolemic hemodilution (ANH) is an autologous transfusion method, using blood collected during surgery, to reduce the need for allogeneic blood transfusion. ANH is controversial because it may lead to various complications. Among the possible complications, anastomotic leakage is one that would have a significant effect on the operation outcome. However, the relationship between ANH and anastomotic site healing requires additional research. Therefore, we conducted this prospective study of ANH, comparing it with standard intraoperative management, undergoing gastric anastomosis in rats. METHODS: Sixteen Sprague-Dawley rats were randomly assigned to three groups: group A, surgery with ANH; group N, surgery with standard intraoperative management; and group C, sham surgery with standard intraoperative management. ANH was performed in group A animals by, removing 5.8–6.6 mL of blood and replacing it with 3 times as much crystalloid. All rats were enthanized on postoperative day 6, and histopathologic analyses were performed. RESULTS: The mean hematocrit values, after hemodilution were 22.0% (range, 18.0%–29.0%), group A; 33.0% (29.0%–35.0%), group N; and 32.5% (29.0%–34.0%), group C. There were significant differences between groups A and N (P = 0.019, P = 0.009, P = 0.004, P = 0.039, and P = 0.027), and between groups N and C (P = 0.006, P = 0.027, P = 0.04, P = 0.008, and P = 0.009) with respect to inflammatory cell numbers, neovascularization, fibroblast numbers, edema and necrosis, respectively; there were no differences between groups A and N. CONCLUSION: In rat model, anastomotic complications did not increase in the ANH group, compared with the standard intraoperative management group.

Toxocaríase experimental em hamster / Experimental toxocariasis in hamsters

INTRODUÇÃO: Toxocaríase é uma infecção parasitária de distribuição global, causada pela fase larval de Toxocara spp. Os hospedeiros naturais são cães e gatos, nos quais o parasita completa o ciclo chegando a fase adulta. Outros hospedeiros podem ser infectados pela fase larval do parasita, após ingestão de ovos embrionados do solo, mãos contaminadas, fomites, ou ingestão de carne ou vísceras de animais infectados. Em hospedeiros paratênicos o parasita não completa o ciclo, invadindo em estágio larval vísceras ou outros tecidos, onde podem sobreviver e induzir a patologia. O presente estudo teve como objetivo caracterizar o hamster (Mesocricetus auratus), como modelo experimental de toxocaríase, inicialmente através do estudo das lesões histopatológicas em fígado, pulmão e rim. A caracterização da resposta imunológica do modelo, foi feita através do estudo de citocinas envolvidas nas respostas Th1 e Th2, e foi sugerida uma correlação entre alterações glomerulares e depósitos de complexos antígenos-anticorpo pré-formados na circulação. MÉTODOS: Hamsters foram inoculados com ovos embrionados de Toxocara canis, e mantidos no biotério do Instituto de Medicina Tropical de São Paulo. O estudo histopatológico foi desenvolvido utilizando-se cortes parafinados corados por hematoxilina e eosina. Para detecção de antígenos nos tecidos foram realizadas reações imunohistoquímicas, utilizando-se anticorpo monoclonal e policlonal anti- Toxocara canis. Utilizando-se o soro dos animais infectados e animais controle, foi realizada pesquisa de antígeno e anticorpo por ELISA. Para pesquisa de imunoglobulinas IgG e IgM e complemento, foram utilizados cortes congelados de rins para realização de reação de Imunofluorescência. Fragmentos de rins foram incluídos para utilização em microscopia eletrônica, para detecção de antígenos de toxocara e de imune complexos. Para caracterização de resposta imunológica foram estudadas citocinas envolvidas na resposta Th1 e Th2 por técnica de...

INTRODUCTION: Toxocariasis is a parasitic infection of global distribution, caused by the larval stage of Toxocara spp. The natural hosts are dogs and cats, in which the parasite completes the cycle reaching adulthood. Other hosts can be infected with the larval stage of the parasite, after ingestion of embryonated eggs from the soil, contaminated hands, fomites, or ingestion of meat or viscera of infected animals. In paratenics hosts the parasite not complete the cycle, encroaching on larval stage in viscera or other tissues where they can survive and induce pathology. The present study aimed to characterize the hamster, Mesocricetus auratus, as experimental model of toxocariasis, initially through the study of histopathological lesions in the liver, lung and kidney. The characterization of immune response model, was made through the study of cytokines Th1 and Th2 responses involved, and a correlation was suggested between glomerular changes and antibody-antigen complexes deposits preformed in the circulation. METHODS: Hamsters were inoculated with embryonated eggs of Toxocara canis, and kept in the bioterium of the Institute of Tropical Medicine of the São Paulo. The histopathologic study was developed using paraffin slides stained by hematoxylin and eosin. For detection of antigens in tissues immunohistochemistry reactions were performed using monoclonal and polyclonal anti-Toxocara canis sera. Using the serum of infected and control animals, search has been carried out of antigen and antibody by ELISA. For the search of immunoglobulins IgG, IgM and complement, were used slides prepared from frozen fragments of kidneys and a immunofluorescence reaction. Fragments of kidneys were included for electron microscopy to detect antigens of Toxocara and immune complexes. For characterization of Th1 and Th2 response cytokines involved were detected by RT-PCR technique. RESULTS: Histopathological findings demonstrated since the beginning of the...

Evaluation of changes in left ventricular myocardial function observed in canine myocardial dysfunction model using a two-dimensional tissue tracking technique

This study was conducted to assess the ability of two-dimensional tissue tracking (2DTT) to evaluate changes in left ventricular (LV) myocardial function associated with sustained high electrical pacing. Pacemakers were implanted at the right ventricular (RV) apex of five female Beagles, and sustained high electrical pacing of 250 beats per minute (bpm) was performed for three consecutive weeks. Conventional echocardiography and 2DTT were performed at baseline, and at every week for three weeks with pacing. The baseline parameters were then compared to those of weeks 1, 2, and 3. Three weeks of pacing resulted in significant reduction of radial and circumferential global strains (p < 0.001). Regional analysis revealed reduction of segmental strains in both radial and circumferential directions, as well as increased dyssynchrony after three weeks of pacing in the radial direction (p = 0.0007). The results of this study revealed the ability of 2DTT to measure radial and circumferential strains in dogs with sustained high-electrical pacing, and allowed assessment of global and regional myocardial function and the degree of dyssynchrony.

Establishment of an experimental model of autogenousoxygenator cardiopulmonary bypass in dogs / 重庆医科大学学报

Objective:To establish an experimental autogenous oxygenator cardiopulmonary bypass in dogs.Methods:Sixteen mongrel dogs were used.Under intravenous anesthesia and artificial respiration,thoracotomy and cardiac cannulations were performed:right atrium cannulation and pulmonary artery cannulation,connecting to reservoir and pump,the right heart bypass system was established;left atrium and ascending aotra cannulation,connecting to reservoir,heat exchanger and pump,the left heart bypass was established.Results:The experimental model was established successfully in fifteen dogs and one failed.Conclusion:The susscessful establishment of this experimental model depends on skillful cannulation,balance of left and right circulation,appropriate body temperature.

An Experimental Animal Model of Anomalous Pancreaticobiliary Duct Union

It is generally believed that the anomalous pancreaticobiliary duct union (APBDU) might be involved in the formation of choledochal cyst and malignancies of hepatopancreaticobiliary system. The purpose of this study is to make an animal model of APBDU similar to that of human. One to two-month-old Mongrel dogs (n=12) were divided into two groups; the control group (n=2) in which sham operation was performed, and the experimental group (n=10) in which the end of distal common bile duct (CBD) was anastomosed to the side of dorsal pancreatic duct to produce APBDU. Serum was obtained for chemical analysis at the 10th postoperative day. The dogs were sacrificed at the 5th week (n=3), the 6th week (n=3), the 7th week (n=2), the 8th week (n=2) and the 6th month (n=2) after the operative intervention. At the day when the experimental animals were sacrificed, operative cholangiogram was taken, and bile juice was obtained for chemical analysis and bacterial culture. The en-bloc specimens of hepatopancreaticobiliary system were obtained for microscopic examination. Serum and bile juice amylase levels were elevated in the experimental group (n=10), but not in the control group (n=2). On operative cholangiogram, there was no evidence of bile duct dilatation in control group (n=2). On the other hand, bile duct in the experimental group was markedly dilated without any evidence of stenosis in all (n=10). Histologic examination of the hepatopancreaticobiliary system in the experimental group resembled the findings of choledochal cyst in human. The APBDU of this animal model can produce bile duct dilatation by pancreaticobiliary reflux. We think that this animal model can be potentially promising for the research about the APBDU associated hepatopancreaticobiliary diseases.

Establishment of Animal Model with Stomach-heat Syndrome / 中药新药与临床药理

Objective SD rat models of stomach-heat syndrome were established to further investigate the physiopathological mechanism of stomach-heat syndrome.Methods Under certain laboratory condition,criteria of stomach-heat syndrome for the animal models were set up firstly.Then decoction of Rhizoma Zingiberis was given to the rats for modeling.Two weeks after modeling,the symptoms of the rats were observed and pathological and biochemical examination was carried out.Weireqing capsules were used to confirm the success of the establishment of stomach-heat syndrome in rats.Results Two weeks after modeling,the model rats had the symptoms of thirst with preference for drinking and reddened tongue.Congestion in gastric mucosa occurred and the levels of 6-keto-PGF1?and TXB2 in the model group were higher than those in the control group.However,in model rats pretreated with Weireqing,the symptoms and signs of stomach-heat syndrome and histological changes were relieved.Conclusion Under the controlled laboratory condition,feeding rats with decoction of Radix Zingiberis can be successfully used to establish animal model of human stomach-heat syndrome .

Experimental Model of Acute Myocardial Infarction Induced by Ligation of Coronary Artery in Swines / 昆明医科大学学报

Objective To establish an experimental animal model of acute myocardial infarction (AMI) in the swine. Methods Under sterilization, the swine’s chest was cut open and the left circumflex coronary artery (LCX) was ligated.Results After the operation, the changes of Electrocardiogram (ECG) and myocardial-enzymes in the blood serum and selective coronary angiography all proved that the animal model of AMI in the swine was successful. Conclusions Ligating coronary was a valuable method to make an animal model of AMI.

THE ESTABLISHMENT OF EXPERIMENTAL ANIMAL MODEL OF CARDIAC CONTUSION / 中国法医学杂志

In the present study an experimental animal model of closed chest cardiac contusion in dogs was successfully established by impacting precardial area at the velocity of 9- 1 - 10. 5m/s with home-made elastic cord propelled impactor, After impact, some significant abnormalities of the left and right ventricular pressure,ECG and heart rate were recorded. Cardiac contusions were demonstrated at au-topsy. The establishment of the experimental cardiac contusion model could provide the tool for further study on nonpenetrating cardiac injury.