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Sample records for animal tumor model

  1. Animal tumors

    International Nuclear Information System (INIS)

    Gillette, E.L.

    1983-01-01

    There are few trained veterinary radiation oncologists and the expense of facilities has limited the extent to which this modality is used. In recent years, a few cobalt teletherapy units and megavoltage x-ray units have been employed in larger veterinary institutions. In addition, some radiation oncologists of human medical institutions are interested and willing to cooperate with veterinarians in the treatment of animal tumors. Carefully designed studies of the response of animal tumors to new modalities serve two valuable purposes. First, these studies may lead to improved tumor control in companion animals. Second, these studies may have important implications to the improvement of therapy of human tumors. Much remains to be learned of animal tumor biology so that appropriate model systems can be described for such studies. Many of the latter studies can be sponsored by agencies interested in the improvement of cancer management

  2. Noninvasive Assessment of Tumor Cell Proliferation in Animal Models

    Directory of Open Access Journals (Sweden)

    Matthias Edinger

    1999-10-01

    Full Text Available Revealing the mechanisms of neoplastic disease and enhancing our ability to intervene in these processes requires an increased understanding of cellular and molecular changes as they occur in intact living animal models. We have begun to address these needs by developing a method of labeling tumor cells through constitutive expression of an optical reporter gene, noninvasively monitoring cellular proliferation in vivo using a sensitive photon detection system. A stable line of HeLa cells that expressed a modified firefly luciferase gene was generated, proliferation of these cells in irradiated severe combined immunodeficiency (SCID mice was monitored. Tumor cells were introduced into animals via subcutaneous, intraperitoneal and intravenous inoculation and whole body images, that revealed tumor location and growth kinetics, were obtained. The number of photons that were emitted from the labeled tumor cells and transmitted through murine tissues was sufficient to detect 1×103 cells in the peritoneal cavity, 1×104 cells at subcutaneous sites and 1×106 circulating cells immediately following injection. The kinetics of cell proliferation, as measured by photon emission, was exponential in the peritoneal cavity and at subcutaneous sites. Intravenous inoculation resulted in detectable colonies of tumor cells in animals receiving more than 1×103 cells. Our demonstrated ability to detect small numbers of tumor cells in living animals noninvasively suggests that therapies designed to treat minimal disease states, as occur early in the disease course and after elimination of the tumor mass, may be monitored using this approach. Moreover, it may be possible to monitor micrometastases and evaluate the molecular steps in the metastatic process. Spatiotemporal analyses of neoplasia will improve the predictability of animal models of human disease as study groups can be followed over time, this method will accelerate development of novel therapeutic

  3. Small Animal [18F]FDG PET Imaging for Tumor Model Study

    International Nuclear Information System (INIS)

    Woo, Sang Keun; Kim, Kyeong Min; Cheon, Gi Jeong

    2008-01-01

    PET allows non-invasive, quantitative and repetitive imaging of biological function in living animals. Small animal PET imaging with [ 18 F]FDG has been successfully applied to investigation of metabolism, receptor, ligand interactions, gene expression, adoptive cell therapy and somatic gene therapy. Experimental condition of animal handling impacts on the biodistribution of [ 18 F]FDG in small animal study. The small animal PET and CT images were registered using the hardware fiducial markers and small animal contour point. Tumor imaging in small animal with small animal [ 18 F]FDG PET should be considered fasting, warming, and isoflurane anesthesia level. Registered imaging with small animal PET and CT image could be useful for the detection of tumor. Small animal experimental condition of animal handling and registration method will be of most importance for small lesion detection of metastases tumor model

  4. More Reasonable Animal Model for Study the Effect of Pneumoperitoneum on Abdominal Tumor Cells

    Science.gov (United States)

    Qijun, Lv; Jiang, Du; Chongshu, Wang

    2018-01-27

    Background: Many animal experimental studies showed that abdominal tumor cells will be widely spread during laparoscopic treatment and grow into metastases. These results are different from clinical observations. There is a hypothesis that too much tumor cells was injected in the animals lead to the results of theses bias. We aim to learn the difference of abdominal cavity volume between human body and the nude mice and to determine reasonable amount of tumor cells in the animal experiments. Methods: The insufflated CO2 volume which represents the capacity of the abdominal cavity was recorded during laparoscopic process in 212 patients and 20 nude mice respectively, the relative volume of nude mice and human body was calculated.Based on data from the literature and this study , the amount of tumor cells in the animal experiments was determined.According to these data, we set up a new animal model and a traditional one respectively,and compared the rate of successful modeling and tumor formation between two animal models. Results: The intraperitoneal volumes of humans and nude mice were 3.01±0.36 L and 0.011±0.001 L respectively.The number of tumor cells that be uesd in animal should be approximately 0.26×105 in terms of known data in human beings.Compared with the traditional animal model which formed a large number of intraperitoneal tumor metastasis, the new animal model was shows more moderately,and the rate of successful modeling was similar. Conclusion: In animal experiments, to simulate the clinical situation, about 0.26×105 tumor cells should be inject in peritoneal cavity of the nude mice. Creative Commons Attribution License

  5. Optimal definition of biological tumor volume using positron emission tomography in an animal model.

    Science.gov (United States)

    Wu, Ingrid; Wang, Hao; Huso, David; Wahl, Richard L

    2015-12-01

    The goal of the study is to investigate (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET)'s ability to delineate the viable portion of a tumor in an animal model using cross-sectional histology as the validation standard. Syngeneic mammary tumors were grown in female Lewis rats. Macroscopic histological images of the transverse tumor sections were paired with their corresponding FDG micro-PET slices of the same cranial-caudal location to form 51 pairs of co-registered images. A binary classification system based on four FDG-PET tumor contouring methods was applied to each pair of images: threshold based on (1) percentage of maximum tumor voxel counts (Cmax), (2) percentage of tumor peak voxel counts (Cpeak), (3) multiples of liver mean voxel counts (Cliver) derived from PERCIST, and (4) an edge-detection-based automated contouring system. The sensitivity, which represented the percentage of viable tumor areas correctly delineated by the gross tumor area (GTA) generated from a particular tumor contouring method, and the ratio (expressed in percentage) of the overestimated areas of a gross tumor area (GTAOE)/whole tumor areas on the macroscopic histology (WTAH), which represented how much a particular GTA extended into the normal structures surrounding the primary tumor target, were calculated. The receiver operating characteristic curves of all pairs of FDG-PET images have a mean area under the curve value of 0.934 (CI of 0.911-0.954), for representing how well each contouring method accurately delineated the viable tumor area. FDG-PET single value threshold tumor contouring based on 30 and 35 % of tumor Cmax or Cpeak and 6 × Cliver + 2 × SD achieved a sensitivity greater than 90 % with a GTAOE/WTAH ratio less than 10 %. Contouring based on 50 % of Cmax or Cpeak had a much lower sensitivity of 67.2-75.6 % with a GTAOE/WTAH ratio of 1.1-1.7 %. Automated edge detection was not reliable in this system. Single

  6. Tumor affinity of radiolabeled peanut agglutinin compared with that of Ga-67 citrate in animal models

    International Nuclear Information System (INIS)

    Yokoyama, K.; Aburano, T.; Watanabe, N.; Kawabata, S.; Ishida, H.; Mukai, K.; Tonami, N.; Hisada, K.

    1985-01-01

    Peanut agglutinin (PNA) binds avidly to the immunodominant group of the tumor associated T antigen. The purpose of this study was to evaluate oncodiagnostic potential of radiolabeled PNA in animal models. PNA was labeled with I-125 or I-131 by Iodogen and also with In-111 by cyclic DTPA anhydride. The biological activity of PNA was examined by a hemaglutination titer with a photometer before and after labeling. Animal tumor models used were Lewis Lung Cancer(LLC), B-16 Melanotic Melanoma(MM), Yoshida Sarcoma(YS), Ehrlich Ascites Tumor(EAT and Hepatoma AH109A(HAH). Inflammatory tissue induced by turpentine oil was used as an abscess model. Serial scintigraphic images were obtained following IV injections of 100 μCi of I-131 or In-111-DTPA-PNA. The tumor affinity of Ga-67 citrate was studied to compare that of radiolabeled PNA. Tissue biodistribution was studied in EAT bearing mice. All of these tumor models except HAH were clearly visible by radiolabeled PNA without subtraction techniques. In the models of LLC and EAT, PNA showed the better accumulation into the tumor tissue than Ga-67 citrate. In YS and MM, PNA represented almost the same accumulation as Ga-67 citrate. The localization of PNA into abscess tissue wasn't found although Ga-67 citrate markedly accumulated into abscess tissue as well as tumor tissue. The clearance of PNA from tumor was slower than those from any other organs. Tumor to muscle ratio was 5.1 at 48hrs. and tumor to blood ratio increased with time to 2.3 at 96hrs. These results suggested that radiolabeled PNA may have a potential in the detection of tumor

  7. Immunological considerations of modern animal models of malignant primary brain tumors

    Directory of Open Access Journals (Sweden)

    James C David

    2009-10-01

    Full Text Available Abstract Recent advances in animal models of glioma have facilitated a better understanding of biological mechanisms underlying gliomagenesis and glioma progression. The limitations of existing therapy, including surgery, chemotherapy, and radiotherapy, have prompted numerous investigators to search for new therapeutic approaches to improve quantity and quality of survival from these aggressive lesions. One of these approaches involves triggering a tumor specific immune response. However, a difficulty in this approach is the the scarcity of animal models of primary CNS neoplasms which faithfully recapitulate these tumors and their interaction with the host's immune system. In this article, we review the existing methods utilized to date for modeling gliomas in rodents, with a focus on the known as well as potential immunological aspects of these models. As this review demonstrates, many of these models have inherent immune system limitations, and the impact of these limitations on studies on the influence of pre-clinical therapeutics testing warrants further attention.

  8. Block of purinergic P2X7R inhibits tumor growth in a C6 glioma brain tumor animal model.

    Science.gov (United States)

    Ryu, Jae K; Jantaratnotai, Nattinee; Serrano-Perez, Maria C; McGeer, Patrick L; McLarnon, James G

    2011-01-01

    We examined the expression and pharmacological modulation of the purinergic receptor P2X7R in a C6 glioma model. Intrastriatal injection of C6 cells induced a time-dependent growth of tumor; at 2 weeks postinjection immunohistochemical analysis demonstrated higher levels of P2X7R in glioma-injected versus control vehicle-injected brains. P2X7R immunoreactivity colocalized with tumor cells and microglia, but not endogenous astrocytes. Intravenous administration of the P2X7R antagonist brilliant blue G (BBG) inhibited tumor growth in a spatially dependent manner from the C6 injection site. Treatment with BBG reduced tumor volume by 52% versus that in controls. Double immunostaining indicated that BBG treatment did not alter microgliosis, astrogliosis, or vasculature vessels in C6-injected animals. In vitro, BBG reduced the expression of P2X7R and glioma chemotaxis induced by the P2X7R ligand, 2',3'-O-(4-benzoyl-benzoyl)adenosine triphosphate (BzATP). Immunohistochemical staining of human glioblastoma tissue samples demonstrated greater expression of P2X7R compared to control nontumor samples. These results suggest that the efficacy of BBG in inhibiting tumor growth is primarily mediated by direct actions of the compound on P2X7R in glioma cells and that pharmacological inhibition of this purinergic receptor might serve as a strategy to slow the progression of brain tumors.

  9. Evaluation of cloned cells, animal model, and ATRA sensitivity of human testicular yolk sac tumor

    Directory of Open Access Journals (Sweden)

    Zhao Junfeng

    2012-03-01

    Full Text Available Abstract The testicular yolk sac tumor (TYST is the most common neoplasm originated from germ cells differentiated abnormally, a major part of pediatric malignant testicular tumors. The present study aimed at developing and validating the in vitro and vivo models of TYST and evaluating the sensitivity of TYST to treatments, by cloning human TYST cells and investigating the histology, ultra-structure, growth kinetics and expression of specific proteins of cloned cells. We found biological characteristics of cloned TYST cells were similar to the yolk sac tumor and differentiated from the columnar to glandular-like or goblet cells-like cells. Chromosomes for tumor identification in each passage met nature of the primary tumor. TYST cells were more sensitive to all-trans-retinoic acid which had significantly inhibitory effects on cell proliferation. Cisplatin induced apoptosis of TYST cells through the activation of p53 expression and down-regulation of Bcl- expression. Thus, we believe that cloned TYST cells and the animal model developed here are useful to understand the molecular mechanism of TYST cells and develop potential therapies for human TYST.

  10. The intraportal injection model: A practical animal model for hepatic metastases and tumor cell dissemination in human colon cancer

    International Nuclear Information System (INIS)

    Thalheimer, Andreas; Waaga-Gasser, Ana M; Otto, Christoph; Bueter, Marco; Illert, Bertram; Gattenlohner, Stefan; Gasser, Martin; Meyer, Detlef; Fein, Martin; Germer, Christoph T

    2009-01-01

    The development of new therapeutic strategies for treatment of metastasized colorectal carcinoma requires biologically relevant and adequate animal models that generate both reproducible metastasis and the dissemination of tumor cells in the form of so-called minimal residual disease (MRD), an expression of the systemic character of neoplastic disease. We injected immunoincompetent nude mice intraportally with different numbers (1 × 10 5 , 1 × 10 6 and 5 × 10 6 cells) of the human colon carcinoma cell lines HT-29 and SW-620 and investigated by histological studies and CK-20 RT-PCR the occurrence of hematogenous metastases and the dissemination of human tumor cells in bone marrow. Only the injection of 1 × 10 6 cells of each colon carcinoma cell line produced acceptable perioperative mortality with reproducible induction of hepatic metastases in up to 89% of all animals. The injection of 1 × 10 6 cells also generated tumor cell dissemination in the bone marrow in up to 63% of animals with hepatic metastases. The present intraportal injection model in immunoincompetent nude mice represents a biologically relevant and adequate animal model for the induction of both reproducible hepatic metastasis and tumor cell dissemination in the bone marrow as a sign of MRD

  11. Myeloid leukemias and virally induced lymphomas in miniature inbred swine; development of a large animal tumor model

    Directory of Open Access Journals (Sweden)

    RAIMON eDURAN-STRUUCK

    2015-11-01

    Full Text Available The lack of a large animal transplantable tumor model has limited the study of novel therapeutic strategies for the treatment of liquid cancers. Swine as a species provide a natural option based on their similarities with humans and their already extensive use in biomedical research. Specifically, the MGH miniature swine herd retains unique genetic characteristics that facilitate the study of hematopoietic cell and solid organ transplantation. Spontaneously arising liquid cancers in these swine, specifically myeloid leukemias and B cell lymphomas, closely resemble human malignancies. The ability to establish aggressive tumor cell lines in vitro from these naturally occurring malignancies makes a transplantable tumor model a close reality. Here, we discuss our experience with myeloid and lymphoid tumors in MHC characterized miniature swine and future approaches regarding the development of a large animal transplantable tumor model.

  12. Nanoparticle-based sorting of circulating tumor cells by epithelial antigen expression during disease progression in an animal model.

    Science.gov (United States)

    Muhanna, Nidal; Mepham, Adam; Mohamadi, Reza M; Chan, Harley; Khan, Tahsin; Akens, Margarete; Besant, Justin D; Irish, Jonathan; Kelley, Shana O

    2015-10-01

    Circulating tumor cells (CTCs) can be used as markers for the detection, characterization, and targeted therapeutic management of cancer. We recently developed a nanoparticle-mediated approach for capture and sorting of CTCs based on their specific epithelial phenotype. In the current study, we investigate the phenotypic transition of tumor cells in an animal model and show the correlation of this transition with tumor progression. VX2 tumor cells were injected into rabbits, and CTCs were evaluated during tumor progression and correlated with computerized tomography (CT) measurements of tumor volume. The results showed a dramatic increase of CTCs during the four weeks of tumor growth. Following resection, CTC levels dropped but then rebounded, likely due to lymph node metastases. Additionally, CTCs showed a marked loss of the epithelial cell adhesion molecule (EpCAM) relative to precursor cells. In conclusion, the device accurately traces disease progression and CTC phenotypic shift in an animal model. The detection of circulating tumor cells (CTCs) has been used to predict disease prognosis. In this study, the authors developed a nanoparticle-mediated platform based on microfluidics to analyze the differential expressions of epithelial cell adhesion molecule (EpCAM) on CTCs in an animal model. It was found that the loss of EpCAM correlated with disease progression. Hence, the use of this platform may be further applied in other cancer models in the future. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. The utility of fecal corticosterone metabolites and animal welfare assessment protocols as predictive parameters of tumor development and animal welfare in a murine xenograft model

    DEFF Research Database (Denmark)

    Jacobsen, Kirsten Rosenmaj; Jørgensen, Pernille Schønning; Pipper, Christian Bressen

    2013-01-01

    The aim of the present study was to evaluate the utility of various non-invasive parameters for the prediction of tumor development and animal welfare in a murine xenograft model in male C.B-17 SCID (C.B-Igh-1(b)/IcrTac-Prkdc(scid)) mice. The study showed that body weight, food and water consumpt......The aim of the present study was to evaluate the utility of various non-invasive parameters for the prediction of tumor development and animal welfare in a murine xenograft model in male C.B-17 SCID (C.B-Igh-1(b)/IcrTac-Prkdc(scid)) mice. The study showed that body weight, food and water...... consumption, and an animal welfare assessment (AWA) protocol revealed marked differences between control and cancer lines as the size of the tumor increased. However, only the AWA protocol was effective in predicting the tumor size and the level of fecal corticosterone metabolites (FCM). FCM levels were......, however, negatively-correlated to the AWA score, and the tumor size, both when evaluated on a given day and when accumulated over the entire period. In conclusion, the present study demonstrated that body weight and food and water consumption were negatively-affected as tumor developed but only the animal...

  14. Animal models

    DEFF Research Database (Denmark)

    Gøtze, Jens Peter; Krentz, Andrew

    2014-01-01

    In this issue of Cardiovascular Endocrinology, we are proud to present a broad and dedicated spectrum of reviews on animal models in cardiovascular disease. The reviews cover most aspects of animal models in science from basic differences and similarities between small animals and the human...

  15. Ultrasonic characterization of three animal mammary tumors from three-dimensional acoustic tissue models

    Science.gov (United States)

    Mamou, Jonathan M.

    This dissertation investigated how three-dimensional (3D) tissue models can be used to improve ultrasonic tissue characterization (UTC) techniques. Anatomic sites in tissue responsible for ultrasonic scattering are unknown, which limits the potential applications of ultrasound for tumor diagnosis. Accurate 3D models of tumor tissues may help identify the scattering sites. Three mammary tumors were investigated: a rat fibroadenoma, a mouse carcinoma, and a mouse sarcoma. A 3D acoustic tissue model, termed 3D impedance map (3DZM), was carefully constructed from consecutive histologic sections for each tumor. Spectral estimates (scatterer size and acoustic concentration) were obtained from the 3DZMs and compared to the same estimates obtained with ultrasound. Scatterer size estimates for three tumors were found to be similar (within 10%). The 3DZMs were also used to extract tissue-specific scattering models. The scattering models were found to allow clear distinction between the three tumors. This distinction demonstrated that UTC techniques may be helpful for noninvasive clinical tumor diagnosis.

  16. Tumor cells growth and survival time with the ketogenic diet in animal models: A systematic review

    Directory of Open Access Journals (Sweden)

    Soheila Khodadadi

    2017-01-01

    Full Text Available Recently, interest in targeted cancer therapies via metabolic pathways has been renewed with the discovery that many tumors become dependent on glucose uptake during anaerobic glycolysis. Also the inability of ketone bodies metabolization due to various deficiencies in mitochondrial enzymes is the major metabolic changes discovered in malignant cells. Therefore, administration of a ketogenic diet (KD which is based on high in fat and low in carbohydrates might inhibit tumor growth and provide a rationale for therapeutic strategies. So, we conducted this systematic review to assess the effects of KD on the tumor cells growth and survival time in animal studies. All databases were searched from inception to November 2015. We systematically searched the PubMed, Scopus, Google Scholars, Science Direct and Cochrane Library according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. To assess the quality of included studies we used SYRCLE's RoB tool. 268 articles were obtained from databases by primary search. Only 13 studies were eligible according to inclusion criteria. From included studies, 9 articles indicate that KD had a beneficial effect on tumor growth and survival time. Tumor types were included pancreatic, prostate, gastric, colon, brain, neuroblastoma and lung cancers. In conclusions, although studies in this field are rare and inconsistence, recent findings have demonstrated that KD can potentially inhibit the malignant cell growth and increase the survival time. Because of differences physiology between animals and humans, future studies in cancer patients treated with a KD are needed.

  17. Tumor Cells Growth and Survival Time with the Ketogenic Diet in Animal Models: A Systematic Review.

    Science.gov (United States)

    Khodadadi, Soheila; Sobhani, Nafiseh; Mirshekar, Somaye; Ghiasvand, Reza; Pourmasoumi, Makan; Miraghajani, Maryam; Dehsoukhteh, Somayeh Shahraki

    2017-01-01

    Recently, interest in targeted cancer therapies via metabolic pathways has been renewed with the discovery that many tumors become dependent on glucose uptake during anaerobic glycolysis. Also the inability of ketone bodies metabolization due to various deficiencies in mitochondrial enzymes is the major metabolic changes discovered in malignant cells. Therefore, administration of a ketogenic diet (KD) which is based on high in fat and low in carbohydrates might inhibit tumor growth and provide a rationale for therapeutic strategies. So, we conducted this systematic review to assess the effects of KD on the tumor cells growth and survival time in animal studies. All databases were searched from inception to November 2015. We systematically searched the PubMed, Scopus, Google Scholars, Science Direct and Cochrane Library according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. To assess the quality of included studies we used SYRCLE's RoB tool. 268 articles were obtained from databases by primary search. Only 13 studies were eligible according to inclusion criteria. From included studies, 9 articles indicate that KD had a beneficial effect on tumor growth and survival time. Tumor types were included pancreatic, prostate, gastric, colon, brain, neuroblastoma and lung cancers. In conclusions, although studies in this field are rare and inconsistence, recent findings have demonstrated that KD can potentially inhibit the malignant cell growth and increase the survival time. Because of differences physiology between animals and humans, future studies in cancer patients treated with a KD are needed.

  18. Experimental drug STA-8666 causes complete tumor regression in animal models of pediatric sarcomas | Center for Cancer Research

    Science.gov (United States)

    New studies from scientists in the NCI Center for Cancer Research’s (CCR) Pediatric Oncology Branch suggest that an experimental drug called STA-8666 could be an effective treatment for the childhood cancers Ewing sarcoma and rhabdomyosarcoma. In mouse models of these diseases, STA-8666 eliminated tumors and prolonged survival beyond that of animals treated with a related drug, irinotecan. Read more…

  19. The Pig as a Large Animal Model for Studying Anti-Tumor Immune Responses

    DEFF Research Database (Denmark)

    Overgaard, Nana Haahr

    The immune system plays a crucial role in cancer development and progression. Cancer immunoediting encompasses three phases: elimination, equilibrium, and escape; together, describing the complex interplay between tumor and immune cells. Specifically, the immune system both protects against cancer...... of autologous tumor cells, underlining the capacity of the Oncopig immune system to mount a cytotoxic anti-tumor response. Using the results from RNA-seq analysis, we propose a potential mechanism for in vivo inhibition of anti-tumor cytotoxicity based on elevated expression of the immunosuppressive genes IDO1...... support that the Oncopig provides a crucial platform for studying anti-tumor immune responses in a large in vivo system, although the model currently only allows preclinical testing of therapeutics against the early stages of cancer....

  20. Imaging of lung metastasis tumor mouse model using [{sup 18}F]FDG small animal PET and CT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, June Youp; Woo, Sang Keun; Lee, Tae Sup [Korea Institute of Radiological and Medical Sciences (KIRAMS), Seoul (Korea, Republic of)] (and others)

    2007-02-15

    The purpose of this study is to image metastaic lung melanoma model with optimal pre-conditions for animal handling by using [{sup 18}F]FDG small animal PET and clinical CT. The pre-conditions for lung region tumor imaging were 16-22 h fasting and warming temperature at 30 .deg. C. Small animal PET image was obtained at 60 min postinjection of 7.4 MBq [{sup 18}F]FDG and compared pattern of [{sup 18}F]FDG uptake and glucose standard uptake value (SUVG) of lung region between Ketamine/Xylazine (Ke/Xy) and Isoflurane (Iso) anesthetized group in normal mice. Metastasis tumor mouse model to lung was established by intravenous injection of B16-F10 cells in C57BL/6 mice. In lung metastasis tumor model, [{sup 18}F]FDG image was obtained and fused with anatomical clinical CT image. Average blood glucose concentration in normal mice were 128.0 {+-} 22.87 and 86.0 {+-} 21.65 mg/dL in Ke/Xy group and Iso group, respectively. Ke/Xy group showed 1.5 fold higher blood glucose concentration than Iso group. Lung to Background ratio (L/B) in SUVG image was 8.6 {+-} 0.48 and 12.1 {+-}0.63 in Ke/Xy group and Iso group, respectively. In tumor detection in lung region, [{sup 18}F]FDG image of Iso group was better than that of Ke/Xy group, because of high L/B ratio. Metastatic tumor location in [{sup 18}F]FDG small animal PET image was confirmed by fusion image using clinical CT. Tumor imaging in small animal lung region with [{sup 18}F]FDG small animal PET should be considered pre-conditions which fasting, warming and an anesthesia during [{sup 18}F]FDG uptake. Fused imaging with small animal PET and CT image could be useful for the detection of metastatic tumor in lung region.

  1. SU-G-IeP4-11: Monitoring Tumor Growth in Subcutaneous Murine Tumor Model in Vivo: A Comparison Between MRI and Small Animal CT

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    Wang, B; He, W; Cvetkovic, D; Chen, L; Fan, J; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States)

    2016-06-15

    Purpose: The purpose of the study is to compare the volume measurement of subcutaneous tumors in mice with different imaging platforms, namely a GE MRI and a Sofie-Biosciences small animal CT scanner. Methods: A549 human lung carcinoma cells and FaDu human head and neck squamous cell carcinoma cells were implanted subcutaneously into flanks of nude mice. Three FaDu tumors and three A549 tumors were included in this study. The MRI scans were done with a GE Signa 1.5 Tesla MR scanner using a fast T2-weighted sequence (70mm FOV and 1.2mm slice thickness), while the CT scans were done with the CT scanner on a Sofie-Biosciences G8 PET/CT platform dedicated for small animal studies (48mm FOV and 0.2mm slice thickness). Imaging contrast agent was not used in this study. Based on the DICOM images from MRI and CT scans, the tumors were contoured with Philips DICOM Viewer and the tumor volumes were obtained by summing up the contoured area and multiplied by the slice thickness. Results: The volume measurements based on the CT scans agree reasonably with that obtained with MR images for the subcutaneous tumors. The mean difference in the absolute tumor volumes between MRI- and CT-based measurements was found to be −6.2% ± 1.0%, with the difference defined as (VMR – VCT)*100%/VMR. Furthermore, we evaluated the normalized tumor volumes, which were defined for each tumor as V/V{sub 0} where V{sub 0} stands for the volume from the first MR or CT scan. The mean difference in the normalized tumor volumes was found to be 0.10% ± 0.96%. Conclusion: Despite the fact that the difference between normal and abnormal tissues is often less clear on small animal CT images than on MR images, one can still obtain reasonable tumor volume information with the small animal CT scans for subcutaneous murine xenograft models.

  2. Intrahepatic transneedle inoculation of VX2 particles for obtaining a solitary hepatic tumor in an animal model

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jin Han; Choi, Jong Cheol; Shin, Tae Beom; Park, Byeong Ho [Dong-A University, School of Medicine, Busan (Korea, Republic of)

    2005-07-15

    The purpose of this study was to develop a large animal (rabbit) model which has a proper solitary intrahepatic tumor with lower leakage rates through less traumatic methods. Consequently, we evaluated tumor progression following the intrahepatic inoculation of VX2 cells into New Zealand white rabbits to acquire baseline data on the progression of a VX2 tumor. Twenty New Zealand white rabbits, each weighting 2.5-3 kg, were selected for this study. A 1 mm{sup 3} VX2 tumor fragment was created and then minced to enable the particles to pass through a 21 G needle mounting in a tuberculin syringe with 0.1 ml of normal saline. The minced VX2 tumor particles were injected into the subcapsular parenchyma of the left hepatic lobe. A 21 G needle was used to avoid penetrating large hepatic vessels. In order to prevent hemorrhage or leakage of the VX2 tumor cells through the injection route, a purse-string suture around the puncture site was made using black silk 4-0. The tumor particles were then injected through the center of the suture. While removing the needle, the suture was tightened to prevent hemorrhage or leakage of the VX2 tumor cells through the injection route. Finally, the injection site was covered with a Surgical patch. The inoculated intrahepatic VX2 tumors were then imaged with a 16 channel multidetector CT every week for the duration of the study. The CT images covered from the lung apex to the pelvic floor. Two radiologists evaluated the size, location, and peritoneal seeding of the tumors as well as metastasis of other organs. Three rabbits were sacrificed as random beginning in the second week, and this process continued on a weekly basis for the duration of the study. The CT images and pathologic findings for the sacrificed rabbits were correlated. The inoculated intrahepatic VX2 tumors were not visible in the first week. By the second week 66.7% were visible on CT images and by the third week all tumors were visible. Of the twenty rabbits, three (15

  3. Anti-tumor effects of metformin in animal models of hepatocellular carcinoma: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Juan Li

    Full Text Available Several studies have reported that metformin can reduce the risk of hepatocellular carcinoma (HCC in diabetes patients. However, the direct anti-HCC effects of metformin have hardly been studied in patients, but have been extensively investigated in animal models of HCC. We therefore performed a systematic review and meta-analysis of animal studies evaluating the effects of metformin on HCC.We collected the relevant studies by searching EMBASE, Medline (OvidSP, Web of Science, Scopus, PubMed Publisher, and Google Scholar. Studies were included according to the following inclusion criteria: HCC, animal study, and metformin intervention. Study quality was assessed using SYRCLE's risk of bias tool. A meta-analysis was performed for the outcome measures: tumor growth (tumor volume, weight and size, tumor number and incidence.The search resulted in 573 references, of which 13 could be included in the review and 12 included in the meta-analysis. The study characteristics of the included studies varied considerably. Two studies used rats, while the others used mice. Only one study used female animals, nine used male, and three studies didn't mention the gender of animals in their experiments. The quality of the included studies was low to moderate based on the assessment of their risk of bias. The meta-analysis showed that metformin significantly inhibited the growth of HCC tumour (SMD -2.20[-2.96,-1.43]; n=16, but no significant effect on the number of tumors (SMD-1.05[-2.13,0.03]; n=5 or the incidence of HCC was observed (RR 0.62[0.33,1.16]; n=6. To investigate the potential sources of significant heterogeneities found in outcome of tumor growth (I2=81%, subgroup analyses of scales of growth measures and of types of animal models used were performed.Metformin appears to have a direct anti-HCC effect in animal models. Although the intrinsic limitations of animal studies, this systematic review could provide an important reference for future

  4. Biological characterization of cetuximab-conjugated gold nanoparticles in a tumor animal model

    Science.gov (United States)

    Kao, Hao-Wen; Lin, Yi-Yu; Chen, Chao-Cheng; Chi, Kwan-Hwa; Tien, Der-Chi; Hsia, Chien-Chung; Lin, Wuu-Jyh; Chen, Fu-Du; Lin, Ming-Hsien; Wang, Hsin-Ell

    2014-07-01

    Gold nanoparticles (AuNPs) are widely applied to the diagnosis and treatment of cancer and can be modified to contain target-specific ligands via gold-thiolate bonding. This study investigated the pharmacokinetics and microdistribution of antibody-mediated active targeting gold nanoparticles in mice with subcutaneous lung carcinoma. We conjugated AuNPs with cetuximab (C225), an antibody-targeting epidermal growth factor receptor (EGFR), and then labeled with In-111, which created EGFR-targeted AuNPs. In vitro studies showed that after a 2 h incubation, the uptake of C225-conjugated AuNPs in high EGFR-expression A549 cells was 14.9-fold higher than that of PEGylated AuNPs; furthermore, uptake was also higher at 3.8-fold when MCF7 cells with lower EGFR-expression were used. MicroSPECT/CT imaging and a biodistribution study conducted by using a A549 tumor xenograft mouse model provided evidence of elevated uptake of the C225-conjugated AuNPs into the tumor cells as a result of active targeting. Moreover, the microdistribution of PEGylated AuNPs revealed that a large portion of AuNPs remained in the tumor interstitium, whereas the C225-conjugated AuNPs displayed enhanced internalization via antibody-mediated endocytosis. Our findings suggest that the anti-EGFR antibody-conjugated AuNPs are likely to be a plausible nano-sized vehicle for drug delivery to EGFR-expressing tumors.

  5. Application of Synthetic Polymeric Scaffolds in Breast Cancer 3D Tissue Cultures and Animal Tumor Models

    Directory of Open Access Journals (Sweden)

    Girdhari Rijal

    2017-01-01

    Full Text Available Preparation of three-dimensional (3D porous scaffolds from synthetic polymers is a challenge to most laboratories conducting biomedical research. Here, we present a handy and cost-effective method to fabricate polymeric hydrogel and porous scaffolds using poly(lactic-co-glycolic acid (PLGA or polycaprolactone (PCL. Breast cancer cells grown on 3D polymeric scaffolds exhibited distinct survival, morphology, and proliferation compared to those on 2D polymeric surfaces. Mammary epithelial cells cultured on PLGA- or PCL-coated slides expressed extracellular matrix (ECM proteins and their receptors. Estrogen receptor- (ER- positive T47D breast cancer cells are less sensitive to 4-hydroxytamoxifen (4-HT treatment when cultured on the 3D porous scaffolds than in 2D cultures. Finally, cancer cell-laden polymeric scaffolds support consistent tumor formation in animals and biomarker expression as seen in human native tumors. Our data suggest that the porous synthetic polymer scaffolds satisfy the basic requirements for 3D tissue cultures both in vitro and in vivo. The scaffolding technology has appealing potentials to be applied in anticancer drug screening for a better control of the progression of human cancers.

  6. Sonic hedgehog in normal and neoplastic proliferation: insight gained from human tumors and animal models.

    Science.gov (United States)

    Wetmore, Cynthia

    2003-02-01

    Cancer arises when a cell accumulates multiple genetic changes that allow it to elude the highly regulated balance between proliferation and apoptosis that an organism employs to suppress inappropriate growth. It has become evident that malignant transformation of a cell or group of cells often involves pathways that are active during normal development but are inappropriately regulated in neoplastic proliferation. Signaling via the Sonic hedgehog pathway is critical to vertebrate development and also appears to play an integral role in the initiation and propagation of some tumors of the muscle, skin and nervous system. Analyses of human tumors have revealed mutations in various components of the Sonic hedgehog signaling pathway that appear to result in the activation of this pathway, as inferred by the increased expression of the transcription factor, Gli1. Interestingly, a proportion of the human tumors and most of those arising in mouse models continue to express the normal Patched allele, suggesting the involvement of additional molecular events in the transformation of the haploinsufficient cells.

  7. Comparative animal models for the study of lymphohematopoietic tumors: strengths and limitations of present approaches.

    Science.gov (United States)

    O'Connor, Owen A; Toner, Lorraine E; Vrhovac, Radovan; Budak-Alpdogan, Tulin; Smith, Emily A; Bergman, Philip

    2005-07-01

    The lymphomas probably represent the most complex and heterogenous set of malignancies known to cancer medicine. Underneath the single term lymphoma exist some of the fastest growing cancers known to science (i.e Burkitt's and lymphoblastic lymphoma), as well as some of the slowest growing (i.e. small lymphocytic lymphoma [SLL] and follicular lymphoma). It is this very biology that can dictate the selection of drugs and treatment approaches for managing these patients, strategies that can range from very aggressive combination chemotherapy administered in an intensive care unit (for example, patients with Burkitt's lymphoma), to watch and wait approaches that may go on for years in patients with SLL. This impressive spectrum of biology emerges from a relatively restricted number of molecular defects. The importance of these different molecular defects is of course greatly influenced by the intrinsic biology that defines the lymphocyte at its different stages of differentiation and maturation. It is precisely this molecular understanding that is beginning to form the basis for a new approach to thinking about lymphoma, and novel approaches to its management. Unfortunately, while our understanding of human lymphoma has blossomed, our ability to generate appropriate animal models reflective of this biology has not. Most preclinical models of these diseases still rely upon sub-cutaneous xenograft models of only the most aggressive lymphomas like Burkitt's lymphoma. While these models clearly serve an important role in understanding biology, and perhaps more importantly, in identifying promising new drugs for these diseases, they fall short in truly representing the broader, more heterogenous biology found in patients. Clearly, depending upon the questions being posed, or the types of drugs being studied, the best model to employ may vary from situation to situation. In this article, we will review the numerous complexities associated with various animal models of

  8. Causation of nervous system tumors in children: insights from traditional and genetically engineered animal models

    International Nuclear Information System (INIS)

    Rice, Jerry M.

    2004-01-01

    Pediatric neurogenic tumors include primitive neuroectodermal tumors (PNETs), especially medulloblastoma; ependymomas and choroid plexus papillomas; astrocytomas; retinoblastoma; and sympathetic neuroblastoma. Meningiomas and nerve sheath tumors, although uncommon in childhood, are also significant because they can result from exposures of children to ionizing radiation. Specific chromosomal loci and specific genes are related to each of these tumor types. Virtually all these genes appear to act as tumor suppressor genes, which are inactivated in tumor cells by mutations or by chromosomal loss. In genetically engineered mice, some genes that are clearly associated with specific human tumors (e.g., RB1 in retinoblastoma and NF2 in meningiomas and schwannomas) have no such effect. Other genetic constructs in mice involving the genes p53, ptc1, and Nf1 have produced tumors remarkably similar to some of the human pediatric neoplasms. Some of these tumors become clinically apparent after only a few weeks, while the mice are still juveniles, especially when two or more tumor suppressor genes are inactivated in the same genetic construct. Conversely, at least one genetic pathway in rodents involving point mutation in the coding region of a transforming gene (neu in malignant schwannomas) does not appear to operate in any human tumors. The nervous system is markedly susceptible to experimental carcinogenesis during early life in rodents, dogs, primates, and other nonhuman species, and there is no obvious reason why this generalization should not also apply to humans. However, except for therapeutic ionizing radiation, no physical, chemical, or biological cause of human pediatric nervous system tumors is known. The failure of experimental transplacental carcinogenesis to mirror human pediatric experience more closely may reflect the need for multiple mutational events in target cells, and for experimental carcinogens that are capable of causing the full spectrum of

  9. Productively infected murine Kaposi's sarcoma-like tumors define new animal models for studying and targeting KSHV oncogenesis and replication.

    Directory of Open Access Journals (Sweden)

    Brittany M Ashlock

    Full Text Available Kaposi's sarcoma (KS is an AIDS-defining cancer caused by the KS-associated herpesvirus (KSHV. KS tumors are composed of KSHV-infected spindle cells of vascular origin with aberrant neovascularization and erythrocyte extravasation. KSHV genes expressed during both latent and lytic replicative cycles play important roles in viral oncogenesis. Animal models able to recapitulate both viral and host biological characteristics of KS are needed to elucidate oncogenic mechanisms, for developing targeted therapies, and to trace cellular components of KS ontogeny. Herein, we describe two new murine models of Kaposi's sarcoma. We found that murine bone marrow-derived cells, whether established in culture or isolated from fresh murine bone marrow, were infectable with rKSHV.219, formed KS-like tumors in immunocompromised mice and produced mature herpesvirus-like virions in vivo. Further, we show in vivo that the histone deacetylase (HDAC inhibitor suberoylanilide hydroxamic acid (SAHA/Vorinostat enhanced viral lytic reactivation. We propose that these novel models are ideal for studying both viral and host contributions to KSHV-induced oncogenesis as well as for testing virally-targeted antitumor strategies for the treatment of Kaposi's sarcoma. Furthermore, our isolation of bone marrow-derived cell populations containing a cell type that, when infected with KSHV, renders a tumorigenic KS-like spindle cell, should facilitate systematic identification of KS progenitor cells.

  10. Optically enhanced blood-brain-barrier crossing of plasmonic-active nanoparticles in preclinical brain tumor animal models

    Science.gov (United States)

    Yuan, Hsiangkuo; Wilson, Christy M.; Li, Shuqin; Fales, Andrew M.; Liu, Yang; Grant, Gerald; Vo-Dinh, Tuan

    2014-02-01

    Nanotechnology provides tremendous biomedical opportunities for cancer diagnosis, imaging, and therapy. In contrast to conventional chemotherapeutic agents where their actual target delivery cannot be easily imaged, integrating imaging and therapeutic properties into one platform facilitates the understanding of pharmacokinetic profiles, and enables monitoring of the therapeutic process in each individual. Such a concept dubbed "theranostics" potentiates translational research and improves precision medicine. One particular challenging application of theranostics involves imaging and controlled delivery of nanoplatforms across blood-brain-barrier (BBB) into brain tissues. Typically, the BBB hinders paracellular flux of drug molecules into brain parenchyma. BBB disrupting agents (e.g. mannitol, focused ultrasound), however, suffer from poor spatial confinement. It has been a challenge to design a nanoplatform not only acts as a contrast agent but also improves the BBB permeation. In this study, we demonstrated the feasibility of plasmonic gold nanoparticles as both high-resolution optical contrast agent and focalized tumor BBB permeation-inducing agent. We specifically examined the microscopic distribution of nanoparticles in tumor brain animal models. We observed that most nanoparticles accumulated at the tumor periphery or perivascular spaces. Nanoparticles were present in both endothelial cells and interstitial matrices. This study also demonstrated a novel photothermal-induced BBB permeation. Fine-tuning the irradiating energy induced gentle disruption of the vascular integrity, causing short-term extravasation of nanomaterials but without hemorrhage. We conclude that our gold nanoparticles are a powerful biocompatible contrast agent capable of inducing focal BBB permeation, and therefore envision a strong potential of plasmonic gold nanoparticle in future brain tumor imaging and therapy.

  11. The effect of an osteolytic tumor on the three-dimensional trabecular bone morphology in an animal model

    Energy Technology Data Exchange (ETDEWEB)

    Kurth, A.A. [Orthopedic Biomechanics Lab. (OBL), Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA (United States); Dept. of Orthopaedic Surgery, University Hospital Frankfurt (Germany); Mueller, R. [Orthopedic Biomechanics Lab. (OBL), Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA (United States)

    2001-02-01

    Objective. To investigate the application of micro-computed tomography ({mu}CT) for the assessment of density differences and deterioration of three-dimensional architecture of trabecular bone in an experimental rat model for tumor- induced osteolytic defects.Design and materials. Walker carcinosarcoma 256 malignant breast cancer cells (W256) were surgically implanted into the medullary canal of the left femur of 15 4-month-old rats. Twenty-eight days after surgery all animals were killed and both femora from each rat were harvested. A total of 30 specimens (left and right femur) were scanned in a desk-top {mu}CT imaging system ({mu}CT 20, Scanco Medical) to assess densitometric and architectural parameters. For each specimen a total of 200 micro-tomographic slices with a resolution of 30 {mu}m in the distal metaphysis was taken. Bone mineral content (BMC) was analyzed for both cortical and trabecular bone (ctBMC), and for trabecular bone only (tBMC). Architectural indices (BV/TV, Tb.N, Tb.Th, Tb.Sp) according to standard definitions used in histomorphometry were calculated for trabecular bone.Results. The quantitative analysis of density parameters revealed significantly (P<0.001) lower values for ctBMC and tBMC in the tumor-bearing group (T) of 26% and 31%, respectively, compared with the contralateral control group. The quantitative analysis revealed significant (P<0.001) changes in the architectural parameters in the tumor-bearing bones compared with the contralateral control group: BV/TV was 30% lower, Tb.N and BS/TV decreased by 24% and 21%, respectively, Tb.Th. decreased by 10% and Tb.Sp. increased by 94%.Conclusions. This study demonstrates that {mu}CT is able to provide three-dimensional parameters of bone mass and trabecular structure in an animal model for tumor-induced bone loss. Recent advances in therapeutic approaches for skeletal diseases such as osteoporosis and metastatic bone disease rely on an understanding of the effects of the agents on the

  12. Optimized time-resolved imaging of contrast kinetics (TRICKS) in dynamic contrast-enhanced MRI after peptide receptor radionuclide therapy in small animal tumor models.

    Science.gov (United States)

    Haeck, Joost; Bol, Karin; Bison, Sander; van Tiel, Sandra; Koelewijn, Stuart; de Jong, Marion; Veenland, Jifke; Bernsen, Monique

    2015-01-01

    Anti-tumor efficacy of targeted peptide-receptor radionuclide therapy (PRRT) relies on several factors, including functional tumor vasculature. Little is known about the effect of PRRT on tumor vasculature. With dynamic contrast-enhanced (DCE-) MRI, functional vasculature is imaged and quantified using contrast agents. In small animals DCE-MRI is a challenging application. We optimized a clinical sequence for fast hemodynamic acquisitions, time-resolved imaging of contrast kinetics (TRICKS), to obtain DCE-MRI images at both high spatial and high temporal resolution in mice and rats. Using TRICKS, functional vasculature was measured prior to PRRT and longitudinally to investigate the effect of treatment on tumor vascular characteristics. Nude mice bearing H69 tumor xenografts and rats bearing syngeneic CA20948 tumors were used to study perfusion following PRRT administration with (177) lutetium octreotate. Both semi-quantitative and quantitative parameters were calculated. Treatment efficacy was measured by tumor-size reduction. Optimized TRICKS enabled MRI at 0.032 mm(3) voxel size with a temporal resolution of less than 5 s and large volume coverage, a substantial improvement over routine pre-clinical DCE-MRI studies. Tumor response to therapy was reflected in changes in tumor perfusion/permeability parameters. The H69 tumor model showed pronounced changes in DCE-derived parameters following PRRT. The rat CA20948 tumor model showed more heterogeneity in both treatment outcome and perfusion parameters. TRICKS enabled the acquisition of DCE-MRI at both high temporal resolution (Tres ) and spatial resolutions relevant for small animal tumor models. With the high Tres enabled by TRICKS, accurate pharmacokinetic data modeling was feasible. DCE-MRI parameters revealed changes over time and showed a clear relationship between tumor size and Ktrans . Copyright © 2015 John Wiley & Sons, Ltd.

  13. An Interactive Tool for Animating Biology, and Its Use in Spatial and Temporal Modeling of a Cancerous Tumor and Its Microenvironment.

    Directory of Open Access Journals (Sweden)

    Naamah Bloch

    Full Text Available The ability to visualize the ongoing events of a computational model of biology is critical, both in order to see the dynamics of the biological system in action and to enable interaction with the model from which one can observe the resulting behavior. To this end, we have built a new interactive animation tool, SimuLife, for visualizing reactive models of cellular biology. SimuLife is web-based, and is freely accessible at http://simulife.weizmann.ac.il/. We have used SimuLife to animate a model that describes the development of a cancerous tumor, based on the individual components of the system and its environment. This has helped in understanding the dynamics of the tumor and its surrounding blood vessels, and in verifying the behavior, fine-tuning the model accordingly, and learning in which way different factors affect the tumor.

  14. Improvement of Parameter Estimations in Tumor Growth Inhibition Models on Xenografted Animals: Handling Sacrifice Censoring and Error Caused by Experimental Measurement on Larger Tumor Sizes.

    Science.gov (United States)

    Pierrillas, Philippe B; Tod, Michel; Amiel, Magali; Chenel, Marylore; Henin, Emilie

    2016-09-01

    The purpose of this study was to explore the impact of censoring due to animal sacrifice on parameter estimates and tumor volume calculated from two diameters in larger tumors during tumor growth experiments in preclinical studies. The type of measurement error that can be expected was also investigated. Different scenarios were challenged using the stochastic simulation and estimation process. One thousand datasets were simulated under the design of a typical tumor growth study in xenografted mice, and then, eight approaches were used for parameter estimation with the simulated datasets. The distribution of estimates and simulation-based diagnostics were computed for comparison. The different approaches were robust regarding the choice of residual error and gave equivalent results. However, by not considering missing data induced by sacrificing the animal, parameter estimates were biased and led to false inferences in terms of compound potency; the threshold concentration for tumor eradication when ignoring censoring was 581 ng.ml(-1), but the true value was 240 ng.ml(-1).

  15. 12/15 Lipoxygenase regulation of colorectal tumorigenesis is determined by the relative tumor levels of its metabolite 12-HETE and 13-HODE in animal models.

    Science.gov (United States)

    Chang, Jian; Jiang, Li; Wang, Yinqiu; Yao, Bing; Yang, Shilin; Zhang, Bixiang; Zhang, Ming-Zhi

    2015-02-20

    Colorectal cancer (CRC) continues to be a major cause of morbidity and mortality. The arachidonic acid (AA) pathway and linoleic acid (LA) pathway have been implicated as important contributors to CRC development and growth. Human 15-lipoxygenase 1 (15-LOX-1) converts LA to anti-tumor 13-S-hydroxyoctadecadienoic acid (13-HODE)and 15-LOX-2 converts AA to 15-hydroxyeicosatetraenoic acid (15-HETE). In addition, human 12-LOX metabolizes AA to pro-tumor 12-HETE. In rodents, the function of 12-LOX and 15-LOX-1 and 15-LOX-2 is carried out by a single enzyme, 12/15-LOX. As a result, conflicting conclusions concerning the role of 12-LOX and 15-LOX have been obtained in animal studies. In the present studies, we determined that PD146176, a selective 15-LOX-1 inhibitor, markedly suppressed 13-HODE generation in human colon cancer HCA-7 cells and HCA-7 tumors, in association with increased tumor growth. In contrast, PD146176 treatment led to decreases in 12-HETE generation in mouse colon cancer MC38 cells and MC38 tumors, in association with tumor inhibition. Surprisingly, deletion of host 12/15-LOX alone led to increased MC38 tumor growth, in association with decreased tumor 13-HODE levels, possibly due to inhibition of 12/15-LOX activity in stroma. Therefore, the effect of 12/15-LOX on colorectal tumorigenesis in mouse models could be affected by tumor cell type (human or mouse), relative 12/15 LOX activity in tumor cells and stroma as well as the relative tumor 13-HODE and 12-HETE levels.

  16. Is 18F-FDG a surrogate tracer to measure tumor hypoxia? Comparison with the hypoxic tracer 14C-EF3 in animal tumor models

    International Nuclear Information System (INIS)

    Christian, Nicolas; Deheneffe, Stephanie; Bol, Anne; De Bast, Marc; Labar, Daniel; Lee, John A.; Gregoire, Vincent

    2010-01-01

    Introduction: Fluorodeoxyglucose (FDG) has been reported as a surrogate tracer to measure tumor hypoxia with positron emission tomography (PET). The hypothesis is that there is an increased uptake of FDG under hypoxic conditions secondary to enhanced glycolysis, compensating the hypoxia-induced loss of cellular energy production. Several studies have already addressed this issue, some with conflicting results. This study aimed to compare the tracers 14 C-EF3 and 18 F-FDG to detect hypoxia in mouse tumor models. Materials and methods: C3H, tumor-bearing mice (FSAII and SCCVII tumors) were injected iv with 14 C-EF3, and 1 h later with 18 F-FDG. Using a specifically designed immobilization device with fiducial markers, PET (Mosaic (registered) , Philips) images were acquired 1 h after the FDG injection. After imaging, the device containing mouse was frozen, transversally sliced and imaged with autoradiography (AR) (FLA-5100, Fujifilm) to obtain high resolution images of the 18 F-FDG distribution within the tumor area. After a 48-h delay allowing for 18 F decay a second AR was performed to image 14 C-EF3 distribution. AR images were aligned to reconstruct the full 3D tumor volume, and were compared with the PET images. Image segmentation with threshold-based methods was applied on both AR and PET images to derive various tracer activity volumes. The matching index DSI (dice similarity index) was then computed. The comparison was performed under normoxic (ambient air, FSAII: n = 4, SCCVII, n = 5) and under hypoxic conditions (10% O 2 breathing, SCCVII: n = 4). Results: On AR, under both ambient air and hypoxic conditions, there was a decreasing similarity between 14 C-EF3 and FDG with higher activity sub-volumes. Under normoxic conditions, when comparing the 10% of tumor voxels with the highest 18 F-FDG or 14 C-EF3 activity, a DSI of 0.24 and 0.20 was found for FSAII and SCCVII, respectively. Under hypoxic conditions, a DSI of 0.36 was observed for SCCVII tumors. When

  17. Multi-targeted DATS Prevents Tumor Progression and Promotes Apoptosis in an Animal Model of Glioblastoma via HDAC-inhibition

    Science.gov (United States)

    Wallace, Gerald C; Haar, Catherine P; Vandergrift, W Alex; Giglio, Pierre; Ray, Swapan K; Patel, Sunil J; Banik, Naren L; Das, Arabinda

    2015-01-01

    Glioblastoma, the most malignant and lethal of brain tumors, remains incurable despite aggressive chemotherapy and surgical interventions. Few new chemotherapeutics for glioblastoma therapy have been explored in preclinical models, and some agents approved for have reached the clinical setting. However success rates are not significant. Previous investigations involving diallyl trisulfide (DATS), a garlic constituent, have indicated significant anti-cancer effects in vitro, including: glioblastoma growth inhibition, extrinsic and intrinsic apoptotic pathway activation, and cell death. DATS has also been shown to inhibit histone deacetylase activity and impede glioblastoma tumor progression. We hypothesized that DATS would block ectopic U87MG induced tumors by inhibiting multiple pro-apoptotic pathways via HDAC. To this end, ectopic tumors were developed in SCID mice and subsequently treated with daily intraperitoneal injections of DATS. Results indicate that a range of DATS doses (10μg/kg-10mg/kg) dose-dependently reduced tumor volume and number of mitotic cells within tumors after seven days. Our histological and biochemical assays demonstrate that DATS reduces mitosis in tumors, decreases HDAC activity, increases in acetylation of H3 and H4, inhibits cell cycle progression, promotes apoptotic cascade activation (m-calpian, Bax, caspase-3) and decreases pro-survival markers (Survivin, Bcl-2, p-Akt, c-Myc, mTOR, EGFR, VEGF). Our data also demonstrates an increase in p21/WAF1 expression, which correlates with increased p53 expression and MDM2 degradation following DATS treatment. Finally, histological assessment and enzyme assays suggest that even the highest dose of DATS administered in this study did not negatively impact hepatic function. These in vivo findings strongly support orthotopic investigation into the therapeutic potential of DATS and further review of the epigenetic mechanisms behind its anti-cancer activities. PMID:23754639

  18. Early Detection of Tumor Response by FLT/MicroPET Imaging in a C26 Murine Colon Carcinoma Solid Tumor Animal Model

    Directory of Open Access Journals (Sweden)

    Wan-Chi Lee

    2011-01-01

    Full Text Available Fluorine-18 fluorodeoxyglucose (18F-FDG positron emission tomography (PET imaging demonstrated the change of glucose consumption of tumor cells, but problems with specificity and difficulties in early detection of tumor response to chemotherapy have led to the development of new PET tracers. Fluorine-18-fluorothymidine (18F-FLT images cellular proliferation by entering the salvage pathway of DNA synthesis. In this study, we evaluate the early response of colon carcinoma to the chemotherapeutic drug, lipo-Dox, in C26 murine colorectal carcinoma-bearing mice by 18F-FDG and 18F-FLT. The male BALB/c mice were bilaterally inoculated with 1×105 and 1×106 C26 tumor cells per flank. Mice were intravenously treated with 10 mg/kg lipo-Dox at day 8 after 18F-FDG and 18F-FLT imaging. The biodistribution of 18F-FDG and 18F-FLT were followed by the microPET imaging at day 9. For the quantitative measurement of microPET imaging at day 9, 18F-FLT was superior to 18F-FDG for early detection of tumor response to Lipo-DOX at various tumor sizes (<0.05. The data of biodistribution showed similar results with those from the quantification of SUV (standard uptake value by microPET imaging. The study indicates that 18F-FLT/microPET is a useful imaging modality for early detection of chemotherapy in the colorectal mouse model.

  19. Effect of gemcitabine on the uptake of (18)F-fluorodeoxyglucose and (18)F-fluorothymidine in lung adenocarcinoma A549 cells and the animal tumor model.

    Science.gov (United States)

    Zhang, Bin; Deng, Sheng-Ming; Guo, Ling-Chuan; Dong, Jia-Jia; Zhu, Yan-Bo; Gao, Yuan; Wang, Zhen-Xin; Cho, William C

    2016-01-01

    Gemcitabine is the first-line drug for nonsmall cell lung cancer, and 18F-fluorodeoxyglucose. (18F-FDG) and 18F-fluorothymidine. (18F-FLT) are positron emission tomography. (PET) imaging agents. The aim of this study was to explore the effect of gemcitabine on the uptake of 18F-FDG and 18F-FLT in A549 cells and the animal tumor model. The inhibitory effects of gemcitabine on cell growth were determined by tetrazolium blue method, and uptake rates of 18F-FDG and 18F-FLT were determined under the same conditions. The adenocarcinoma-bearing nude mice before and after gemcitabine treatments were performed microPET imaging with 18F-FDG and 18F-FLT. Hematoxylin and eosin staining and immunohistochemical analysis of tumor specimens were conducted. After the administration of gemcitabine, positive correlations were observed between inhibition of 18F-FDG or 18F.FLT uptake and cell growth. (r = 0.957 or 0.981, P cells at the dose of 60 mmol/L, and the expression of glucose transporter protein-1, Ki-67 and proliferating cell nuclear antigen in tumor cells were inhibited. 18F-FLT imaging can assess the proliferation of tumor cells and 18F-FDG imaging can reflect the changes of the tumor microenvironment after administration of gemcitabine.

  20. Synchrotron supported Dei/KES of a brain tumor in an animal model: The search for a microimaging modality

    International Nuclear Information System (INIS)

    Mannan, K.A.; Schueltke, E.; Menk, R.H.; Siu, K.; Pavlov, K.; Kelly, M.; McLoughlin, G.; Beveridge, T.; Tromba, G.; Juurlink, B.H.; Chapman, D.; Rigon, L.; Griebel, R.W.

    2005-01-01

    Glioblastoma multiforme (GBM) is the commonest and most aggressive primary brain tumor in humans. The high rate of tumor recurrence results in a poor prognosis despite multimodality treatment. One reason for high rate of recurrence is the invasive nature of the tumor into the surrounding normal brain tissue or multifocal occurrence at sites remote from that of the primary tumor establishment. Existing imaging demonstrates the primary tumor but fail to show the residual tumor microaggregates left behind following initial treatment. In this study, we employed diffraction-enhanced imaging (DEI) in an attempt to find an imaging modality that will provide visualization of residual disease that is not be apparent on MRI or CT scans

  1. Protective Vaccination against Papillomavirus-Induced Skin Tumors under Immunocompetent and Immunosuppressive Conditions: A Preclinical Study Using a Natural Outbred Animal Model

    Science.gov (United States)

    Vinzón, Sabrina E.; Braspenning-Wesch, Ilona; Müller, Martin; Geissler, Edward K.; Nindl, Ingo; Gröne, Hermann-Josef

    2014-01-01

    Certain cutaneous human papillomaviruses (HPVs), which are ubiquitous and acquired early during childhood, can cause a variety of skin tumors and are likely involved in the development of non-melanoma skin cancer, especially in immunosuppressed patients. Hence, the burden of these clinical manifestations demands for a prophylactic approach. To evaluate whether protective efficacy of a vaccine is potentially translatable to patients, we used the rodent Mastomys coucha that is naturally infected with Mastomys natalensis papillomavirus (MnPV). This skin type papillomavirus induces not only benign skin tumours, such as papillomas and keratoacanthomas, but also squamous cell carcinomas, thereby allowing a straightforward read-out for successful vaccination in a small immunocompetent laboratory animal. Here, we examined the efficacy of a virus-like particle (VLP)-based vaccine on either previously or newly established infections. VLPs raise a strong and long-lasting neutralizing antibody response that confers protection even under systemic long-term cyclosporine A treatment. Remarkably, the vaccine completely prevents the appearance of benign as well as malignant skin tumors. Protection involves the maintenance of a low viral load in the skin by an antibody-dependent prevention of virus spread. Our results provide first evidence that VLPs elicit an effective immune response in the skin under immunocompetent and immunosuppressed conditions in an outbred animal model, irrespective of the infection status at the time of vaccination. These findings provide the basis for the clinical development of potent vaccination strategies against cutaneous HPV infections and HPV-induced tumors, especially in patients awaiting organ transplantation. PMID:24586150

  2. Modelling Farm Animal Welfare

    Science.gov (United States)

    Collins, Lisa M.; Part, Chérie E.

    2013-01-01

    Simple Summary In this review paper we discuss the different modeling techniques that have been used in animal welfare research to date. We look at what questions they have been used to answer, the advantages and pitfalls of the methods, and how future research can best use these approaches to answer some of the most important upcoming questions in farm animal welfare. Abstract The use of models in the life sciences has greatly expanded in scope and advanced in technique in recent decades. However, the range, type and complexity of models used in farm animal welfare is comparatively poor, despite the great scope for use of modeling in this field of research. In this paper, we review the different modeling approaches used in farm animal welfare science to date, discussing the types of questions they have been used to answer, the merits and problems associated with the method, and possible future applications of each technique. We find that the most frequently published types of model used in farm animal welfare are conceptual and assessment models; two types of model that are frequently (though not exclusively) based on expert opinion. Simulation, optimization, scenario, and systems modeling approaches are rarer in animal welfare, despite being commonly used in other related fields. Finally, common issues such as a lack of quantitative data to parameterize models, and model selection and validation are discussed throughout the review, with possible solutions and alternative approaches suggested. PMID:26487411

  3. Animal models of dementia

    DEFF Research Database (Denmark)

    Olsson, I. Anna S.; Sandøe, Peter

    2011-01-01

    This chapter aims to encourage scientists and others interested in the use of animal models of disease – specifically, in the study of dementia – to engage in ethical reflection. It opens with a general discussion of the moral acceptability of animal use in research. Three ethical approaches are ...

  4. Animal models of dementia

    DEFF Research Database (Denmark)

    Olsson, I. Anna S.; Sandøe, Peter

    2011-01-01

    This chapter aims to encourage scientists and others interested in the use of animal models of disease – specifically, in the study of dementia – to engage in ethical reflection. It opens with a general discussion of the moral acceptability of animal use in research. Three ethical approaches...

  5. Implication of Soluble Forms of Cell Adhesion Molecules in Infectious Disease and Tumor: Insights from Transgenic Animal Models

    Directory of Open Access Journals (Sweden)

    Etsuro Ono

    2018-01-01

    Full Text Available Cell adhesion molecules (CAMs are surface ligands, usually glycoproteins, which mediate cell-to-cell adhesion. They play a critical role in maintaining tissue integrity and mediating migration of cells, and some of them also act as viral receptors. It has been known that soluble forms of the viral receptors bind to the surface glycoproteins of the viruses and neutralize them, resulting in inhibition of the viral entry into cells. Nectin-1 is one of important CAMs belonging to immunoglobulin superfamily and herpesvirus entry mediator (HVEM is a member of the tumor necrosis factor (TNF receptor family. Both CAMs also act as alphaherpesvirus receptor. Transgenic mice expressing the soluble form of nectin-1 or HVEM showed almost complete resistance against the alphaherpesviruses. As another CAM, sialic acid-binding immunoglobulin-like lectins (Siglecs that recognize sialic acids are also known as an immunoglobulin superfamily member. Siglecs play an important role in the regulation of immune cell functions in infectious diseases, inflammation, neurodegeneration, autoimmune diseases and cancer. Siglec-9 is one of Siglecs and capsular polysaccharide (CPS of group B Streptococcus (GBS binds to Siglec-9 on neutrophils, leading to suppress host immune response and provide a survival advantage to the pathogen. In addition, Siglec-9 also binds to tumor-produced mucins such as MUC1 to lead negative immunomodulation. Transgenic mice expressing the soluble form of Siglec-9 showed significant resistance against GBS infection and remarkable suppression of MUC1 expressing tumor proliferation. This review describes recent developments in the understanding of the potency of soluble forms of CAMs in the transgenic mice and discusses potential therapeutic interventions that may alter the outcomes of certain diseases.

  6. Animal models of tinnitus.

    Science.gov (United States)

    Brozoski, Thomas J; Bauer, Carol A

    2016-08-01

    Presented is a thematic review of animal tinnitus models from a functional perspective. Chronic tinnitus is a persistent subjective sound sensation, emergent typically after hearing loss. Although the sensation is experientially simple, it appears to have central a nervous system substrate of unexpected complexity that includes areas outside of those classically defined as auditory. Over the past 27 years animal models have significantly contributed to understanding tinnitus' complex neurophysiology. In that time, a diversity of models have been developed, each with its own strengths and limitations. None has clearly become a standard. Animal models trace their origin to the 1988 experiments of Jastreboff and colleagues. All subsequent models derive some of their features from those experiments. Common features include behavior-dependent psychophysical determination, acoustic conditions that contrast objective sound and silence, and inclusion of at least one normal-hearing control group. In the present review, animal models have been categorized as either interrogative or reflexive. Interrogative models use emitted behavior under voluntary control to indicate hearing. An example would be pressing a lever to obtain food in the presence of a particular sound. In this type of model animals are interrogated about their auditory sensations, analogous to asking a patient, "What do you hear?" These models require at least some training and motivation management, and reflect the perception of tinnitus. Reflexive models, in contrast, employ acoustic modulation of an auditory reflex, such as the acoustic startle response. An unexpected loud sound will elicit a reflexive motor response from many species, including humans. Although involuntary, acoustic startle can be modified by a lower-level preceding event, including a silent sound gap. Sound-gap modulation of acoustic startle appears to discriminate tinnitus in animals as well as humans, and requires no training or

  7. Animal models of sarcoidosis.

    Science.gov (United States)

    Hu, Yijie; Yibrehu, Betel; Zabini, Diana; Kuebler, Wolfgang M

    2017-03-01

    Sarcoidosis is a debilitating, inflammatory, multiorgan, granulomatous disease of unknown cause, commonly affecting the lung. In contrast to other chronic lung diseases such as interstitial pulmonary fibrosis or pulmonary arterial hypertension, there is so far no widely accepted or implemented animal model for this disease. This has hampered our insights into the etiology of sarcoidosis, the mechanisms of its pathogenesis, the identification of new biomarkers and diagnostic tools and, last not least, the development and implementation of novel treatment strategies. Over past years, however, a number of new animal models have been described that may provide useful tools to fill these critical knowledge gaps. In this review, we therefore outline the present status quo for animal models of sarcoidosis, comparing their pros and cons with respect to their ability to mimic the etiological, clinical and histological hallmarks of human disease and discuss their applicability for future research. Overall, the recent surge in animal models has markedly expanded our options for translational research; however, given the relative early stage of most animal models for sarcoidosis, appropriate replication of etiological and histological features of clinical disease, reproducibility and usefulness in terms of identification of new therapeutic targets and biomarkers, and testing of new treatments should be prioritized when considering the refinement of existing or the development of new models.

  8. Comparison of drug and cell-based delivery: engineered adult mesenchymal stem cells expressing soluble tumor necrosis factor receptor II prevent arthritis in mouse and rat animal models.

    Science.gov (United States)

    Liu, Linda N; Wang, Gang; Hendricks, Kyle; Lee, Keunmyoung; Bohnlein, Ernst; Junker, Uwe; Mosca, Joseph D

    2013-05-01

    Rheumatoid arthritis (RA) is a systemic autoimmune disease with unknown etiology where tumor necrosis factor-α (TNFα) plays a critical role. Etanercept, a recombinant fusion protein of human soluble tumor necrosis factor receptor II (hsTNFR) linked to the Fc portion of human IgG1, is used to treat RA based on the rationale that sTNFR binds TNFα and blocks TNFα-mediated inflammation. We compared hsTNFR protein delivery from genetically engineered human mesenchymal stem cells (hMSCs) with etanercept. Blocking TNFα-dependent intercellular adhesion molecule-1 expression on transduced hMSCs and inhibition of nitric oxide production from TNFα-treated bovine chondrocytes by conditioned culture media from transduced hMSCs demonstrated the functionality of the hsTNFR construction. Implanted hsTNFR-transduced mesenchymal stem cells (MSCs) reduced mouse serum circulating TNFα generated from either implanted TNFα-expressing cells or lipopolysaccharide induction more effectively than etanercept (TNFα, 100%; interleukin [IL]-1α, 90%; and IL-6, 60% within 6 hours), suggesting faster clearance of the soluble tumor necrosis factor receptor (sTNFR)-TNFα complex from the animals. In vivo efficacy of sTNFR-transduced MSCs was illustrated in two (immune-deficient and immune-competent) arthritic rodent models. In the antibody-induced arthritis BalbC/SCID mouse model, intramuscular injection of hsTNFR-transduced hMSCs reduced joint inflammation by 90% compared with untransduced hMSCs; in the collagen-induced arthritis Fischer rat model, both sTNFR-transduced rat MSCs and etanercept inhibited joint inflammation by 30%. In vitro chondrogenesis assays showed the ability of TNFα and IL1α, but not interferon γ, to inhibit hMSC differentiation to chondrocytes, illustrating an additional negative role for inflammatory cytokines in joint repair. The data support the utility of hMSCs as therapeutic gene delivery vehicles and their potential to be used in alleviating inflammation

  9. Animal Models of Glaucoma

    Directory of Open Access Journals (Sweden)

    Rachida A. Bouhenni

    2012-01-01

    Full Text Available Glaucoma is a heterogeneous group of disorders that progressively lead to blindness due to loss of retinal ganglion cells and damage to the optic nerve. It is a leading cause of blindness and visual impairment worldwide. Although research in the field of glaucoma is substantial, the pathophysiologic mechanisms causing the disease are not completely understood. A wide variety of animal models have been used to study glaucoma. These include monkeys, dogs, cats, rodents, and several other species. Although these models have provided valuable information about the disease, there is still no ideal model for studying glaucoma due to its complexity. In this paper we present a summary of most of the animal models that have been developed and used for the study of the different types of glaucoma, the strengths and limitations associated with each species use, and some potential criteria to develop a suitable model.

  10. ANIMAL MODELS IN SURGICAL

    African Journals Online (AJOL)

    ASSEMBLED BY

    1 Dept.of Veterinary Surgery and Medicine 2Veterinary Teaching Hospital Ahmadu Bello University. Zaria .... unnecessary suffering., Administration of poisons .... way that humans are. Vivisection/ Surgical Training And Research. Animal model use: In both the human and veterinary medical practice, there continue to be ...

  11. Animal models of sepsis.

    Science.gov (United States)

    Fink, Mitchell P

    2014-01-01

    Sepsis remains a common, serious, and heterogeneous clinical entity that is difficult to define adequately. Despite its importance as a public health problem, efforts to develop and gain regulatory approval for a specific therapeutic agent for the adjuvant treatment of sepsis have been remarkably unsuccessful. One step in the critical pathway for the development of a new agent for adjuvant treatment of sepsis is evaluation in an appropriate animal model of the human condition. Unfortunately, the animal models that have been used for this purpose have often yielded misleading findings. It is likely that there are multiple reasons for the discrepancies between the results obtained in tests of pharmacological agents in animal models of sepsis and the outcomes of human clinical trials. One of important reason may be that the changes in gene expression, which are triggered by trauma or infection, are different in mice, a commonly used species for preclinical testing, and humans. Additionally, many species, including mice and baboons, are remarkably resistant to the toxic effects of bacterial lipopolysaccharide, whereas humans are exquisitely sensitive. New approaches toward the use of animals for sepsis research are being investigated. But, at present, results from preclinical studies of new therapeutic agents for sepsis must be viewed with a degree of skepticism.

  12. Animal Models of Atherosclerosis

    Science.gov (United States)

    Getz, Godfrey S.; Reardon, Catherine A.

    2012-01-01

    Atherosclerosis is a chronic inflammatory disorder that is the underlying cause of most cardiovascular disease. Both cells of the vessel wall and cells of the immune system participate in atherogenesis. This process is heavily influenced by plasma lipoproteins, genetics and the hemodynamics of the blood flow in the artery. A variety of small and large animal models have been used to study the atherogenic process. No model is ideal as each has its own advantages and limitations with respect to manipulation of the atherogenic process and modeling human atherosclerosis or lipoprotein profile. Useful large animal models include pigs, rabbits and non-human primates. Due in large part to the relative ease of genetic manipulation and the relatively short time frame for the development of atherosclerosis, murine models are currently the most extensively used. While not all aspects of murine atherosclerosis are identical to humans, studies using murine models have suggested potential biological processes and interactions that underlie this process. As it becomes clear that different factors may influence different stages of lesion development, the use of mouse models with the ability to turn on or delete proteins or cells in tissue specific and temporal manner will be very valuable. PMID:22383700

  13. Animal models of spondyloarthritis.

    Science.gov (United States)

    Lories, Rik J U

    2006-07-01

    The aim of this article is to review new insights into spondyloarthritis obtained in animal models during the last year. HLA-B27 misfolding has been demonstrated in HLA-B27/human beta2-microglobulin transgenic rats. HLA-B27 misfolding is associated with a typical unfolded protein stress response and with an interferon-response signature. Prebiotic treatment of these rats reduced colitis and arthritis. Proteoglycan-induced spondylitis is distinct from proteoglycan-induced arthritis. Specific susceptibility loci for proteoglycan-induced spondylitis have been demonstrated. Bone morphogenetic proteins are important in new cartilage and bone formation in ankylosing enthesitis. Psoriasis and psoriatic arthritis-like disease develops in conditional double JunB/c-Jun knockout mice. Insights into the molecular signaling pathways driving HLA-B27 associated spondylitis, autoimmune spondylitis, ankylosing enthesitis and psoriasis, resulting from animal models, identify new and specific therapeutic targets in spondyloarthritis.

  14. Animal models of sepsis

    OpenAIRE

    Fink, Mitchell P

    2013-01-01

    Sepsis remains a common, serious, and heterogeneous clinical entity that is difficult to define adequately. Despite its importance as a public health problem, efforts to develop and gain regulatory approval for a specific therapeutic agent for the adjuvant treatment of sepsis have been remarkably unsuccessful. One step in the critical pathway for the development of a new agent for adjuvant treatment of sepsis is evaluation in an appropriate animal model of the human condition. Unfortunately, ...

  15. Animal Models of Hemophilia

    Science.gov (United States)

    Sabatino, Denise E.; Nichols, Timothy C.; Merricks, Elizabeth; Bellinger, Dwight A.; Herzog, Roland W.; Monahan, Paul E.

    2013-01-01

    The X-linked bleeding disorder hemophilia is caused by mutations in coagulation factor VIII (hemophilia A) or factor IX (hemophilia B). Unless prophylactic treatment is provided, patients with severe disease (less than 1% clotting activity) typically experience frequent spontaneous bleeds. Current treatment is largely based on intravenous infusion of recombinant or plasma-derived coagulation factor concentrate. More effective factor products are being developed. Moreover, gene therapies for sustained correction of hemophilia are showing much promise in pre-clinical studies and in clinical trials. These advances in molecular medicine heavily depend on availability of well-characterized small and large animal models of hemophilia, primarily hemophilia mice and dogs. Experiments in these animals represent important early and intermediate steps of translational research aimed at development of better and safer treatments for hemophilia, such a protein and gene therapies or immune tolerance protocols. While murine models are excellent for studies of large groups of animals using genetically defined strains, canine models are important for testing scale-up and for longer-term follow-up as well as for studies that require larger blood volumes. PMID:22137432

  16. Animal models of schizophrenia

    Science.gov (United States)

    Jones, CA; Watson, DJG; Fone, KCF

    2011-01-01

    Developing reliable, predictive animal models for complex psychiatric disorders, such as schizophrenia, is essential to increase our understanding of the neurobiological basis of the disorder and for the development of novel drugs with improved therapeutic efficacy. All available animal models of schizophrenia fit into four different induction categories: developmental, drug-induced, lesion or genetic manipulation, and the best characterized examples of each type are reviewed herein. Most rodent models have behavioural phenotype changes that resemble ‘positive-like’ symptoms of schizophrenia, probably reflecting altered mesolimbic dopamine function, but fewer models also show altered social interaction, and learning and memory impairment, analogous to negative and cognitive symptoms of schizophrenia respectively. The negative and cognitive impairments in schizophrenia are resistant to treatment with current antipsychotics, even after remission of the psychosis, which limits their therapeutic efficacy. The MATRICS initiative developed a consensus on the core cognitive deficits of schizophrenic patients, and recommended a standardized test battery to evaluate them. More recently, work has begun to identify specific rodent behavioural tasks with translational relevance to specific cognitive domains affected in schizophrenia, and where available this review focuses on reporting the effect of current and potential antipsychotics on these tasks. The review also highlights the need to develop more comprehensive animal models that more adequately replicate deficits in negative and cognitive symptoms. Increasing information on the neurochemical and structural CNS changes accompanying each model will also help assess treatments that prevent the development of schizophrenia rather than treating the symptoms, another pivotal change required to enable new more effective therapeutic strategies to be developed. LINKED ARTICLES This article is part of a themed issue on

  17. Combination of vatalanib and a 20-HETE synthesis inhibitor results in decreased tumor growth in an animal model of human glioma

    Directory of Open Access Journals (Sweden)

    Shankar A

    2016-03-01

    different treatment groups: vehicle, vatalanib (oral treatment 50 mg/kg/d, HET0016 (intraperitoneal treatment 10 mg/kg/d, and combined (vatalanib and HET0016. Following scheduled treatments, all animals underwent magnetic resonance imaging on day 22, followed by euthanasia. Brain specimens were equally divided for immunohistochemistry and protein array analysis.Results: Our results demonstrated a trend that HET0016, alone or in combination with vatalanib, is capable of controlling the tumor growth compared with that of vatalanib alone, indicating attenuation of the unwanted effect of vatalanib. When both vatalanib and HET0016 were administered together on the day of the tumor implantation (0–21 days treatment, tumor volume, tumor blood volume, permeability, extravascular and extracellular space volume, tumor cell proliferation, and cell migration were decreased compared with that of the vehicle-treated group. Conclusion: HET0016 is capable of controlling tumor growth and migration, but these effects are dependent on the timing of drug administration. The addition of HET0016 to vatalanib may attenuate the unwanted effect of vatalanib.Keywords: magnetic resonance imaging, glioblastoma, antiangiogenic treatments, HET0016, vascular parameters, protein array

  18. The rat as animal model in breast cancer research: a histopathological study of radiation- and hormone-induced rat mammary tumors

    International Nuclear Information System (INIS)

    Zwieten, M.J. van.

    1984-01-01

    One of the goals of this monograph is to present data on the frequency of mammary neoplasms following irradiation and/or hormone administration in intact and castrated female rats of three strains allowed to live their natural life spans. These data are intended to give an overview of the effects of radiation and hormonal manipulation on the mammary gland based on histological examination of necropsied rats and using standard morphological criteria for mammary tumors. The second goal of this monograph is to provide detailed histological descriptions of the mammary tumors found in the various experimental groups as well as in several groups of untreated control rats. The aims are to examine whether possible strain-related and treatment-related differences in morphology or growth patterns exist, as well as to define the pathogensis of radiation-induced rat mammary tumors through the study of early lesions. An attempt will be made to describe tumor characteristics which may be of comparative value in identifying tumor types (and their induction methods) useful as models for specific human breast neoplasms. A rat mammary tumor classification system reflecting the morphological features useful for comparative purposes is also presented. (Auth.)

  19. Activation of the PI3K/AKT pathway induces urothelial carcinoma of the renal pelvis: identification in human tumors and confirmation in animal models.

    Science.gov (United States)

    Qian, Chao-Nan; Furge, Kyle A; Knol, Jared; Huang, Dan; Chen, Jindong; Dykema, Karl J; Kort, Eric J; Massie, Aaron; Khoo, Sok Kean; Vanden Beldt, Kristin; Resau, James H; Anema, John; Kahnoski, Richard J; Morreau, Hans; Camparo, Philippe; Comperat, Eva; Sibony, Mathilde; Denoux, Yves; Molinie, Vincent; Vieillefond, Annick; Eng, Charis; Williams, Bart O; Teh, Bin Tean

    2009-11-01

    Urothelial carcinoma of the renal pelvis is a deadly disease with an unclear tumorigenic mechanism. We conducted gene expression profiling on a set of human tumors of this type and identified a phosphatidylinositol 3-kinase (PI3K)/AKT activation expression signature in 76.9% (n = 13) of our samples. Sequence analysis found both activating mutations of PIK3CA (13.6%, n = 22) and loss of heterozygosity at the PTEN locus (25%, n = 8). In contrast, none of the other subtypes of kidney neoplasms (e.g., clear-cell renal cell carcinoma) harbored PIK3CA mutations (n = 87; P elevation of phosphorylated mammalian target of rapamycin (mTOR; 63.6%, n = 11). To confirm the role of the PI3K/AKT pathway in urothelial carcinoma, we generated mice containing biallelic inactivation of Pten in the urogenital epithelia. These mice developed typical renal pelvic urothelial carcinomas, with an incidence of 57.1% in mice older than 1 year. Laser capture microdissection followed by PCR confirmed the deletion of Pten exons 4 and 5 in the animal tumor cells. Immunohistochemical analyses showed increased phospho-mTOR and phospho-S6K levels in the animal tumors. Renal lymph node metastases were found in 15.8% of the animals with urothelial carcinoma. In conclusion, we identified and confirmed an important role for the PI3K/AKT pathway in the development of urothelial carcinoma and suggested that inhibitors of this pathway (e.g., mTOR inhibitor) may serve as effective therapeutic agents.

  20. Skull base tumor model.

    Science.gov (United States)

    Gragnaniello, Cristian; Nader, Remi; van Doormaal, Tristan; Kamel, Mahmoud; Voormolen, Eduard H J; Lasio, Giovanni; Aboud, Emad; Regli, Luca; Tulleken, Cornelius A F; Al-Mefty, Ossama

    2010-11-01

    Resident duty-hours restrictions have now been instituted in many countries worldwide. Shortened training times and increased public scrutiny of surgical competency have led to a move away from the traditional apprenticeship model of training. The development of educational models for brain anatomy is a fascinating innovation allowing neurosurgeons to train without the need to practice on real patients and it may be a solution to achieve competency within a shortened training period. The authors describe the use of Stratathane resin ST-504 polymer (SRSP), which is inserted at different intracranial locations to closely mimic meningiomas and other pathological entities of the skull base, in a cadaveric model, for use in neurosurgical training. Silicone-injected and pressurized cadaveric heads were used for studying the SRSP model. The SRSP presents unique intrinsic metamorphic characteristics: liquid at first, it expands and foams when injected into the desired area of the brain, forming a solid tumorlike structure. The authors injected SRSP via different passages that did not influence routes used for the surgical approach for resection of the simulated lesion. For example, SRSP injection routes included endonasal transsphenoidal or transoral approaches if lesions were to be removed through standard skull base approach, or, alternatively, SRSP was injected via a cranial approach if the removal was planned to be via the transsphenoidal or transoral route. The model was set in place in 3 countries (US, Italy, and The Netherlands), and a pool of 13 physicians from 4 different institutions (all surgeons and surgeons in training) participated in evaluating it and provided feedback. All 13 evaluating physicians had overall positive impressions of the model. The overall score on 9 components evaluated--including comparison between the tumor model and real tumor cases, perioperative requirements, general impression, and applicability--was 88% (100% being the best possible

  1. Human tumor infiltrating lymphocytes cooperatively regulate prostate tumor growth in a humanized mouse model

    OpenAIRE

    Roth, Michael D; Harui, Airi

    2015-01-01

    BACKGROUND: The complex interactions that occur between human tumors, tumor infiltrating lymphocytes (TIL) and the systemic immune system are likely to define critical factors in the host response to cancer. While conventional animal models have identified an array of potential anti-tumor therapies, mouse models often fail to translate into effective human treatments. Our goal is to establish a humanized tumor model as a more effective pre-clinical platform for understanding and manipulating ...

  2. Animal models for cancer cachexia.

    Science.gov (United States)

    Ballarò, Riccardo; Costelli, Paola; Penna, Fabio

    2016-12-01

    Cancer cachexia is a frequent syndrome that affects patient quality of life, anticancer treatment effectiveness, and overall survival. The lack of anticancer cachexia therapies likely relies on the complexity of the syndrome that renders difficult to design appropriate clinical trials and, conversely, on the insufficient knowledge of the underlying pathogenetic mechanisms. The aim of this review is to collect the most relevant latest information regarding cancer cachexia with a special focus on the experimental systems adopted for modeling the disease in translational studies. The scenario of preclinical models for the study of cancer cachexia is not static and is rapidly evolving in parallel with new prospective treatment options. The well established syngeneic models using rodent cancer cells injected ectopically are now used alongside new ones featuring orthotopic injection, human cancer cell or patient-derived xenograft, or spontaneous tumors in genetically engineered mice. The use of more complex animal models that better resemble cancer cachexia, ideally including also the administration of chemotherapy, will expand the understanding of the underlying mechanisms and will allow a more reliable evaluation of prospective drugs for translational purposes.

  3. Microparticles and cancer thrombosis in animal models.

    Science.gov (United States)

    Mege, Diane; Mezouar, Soraya; Dignat-George, Françoise; Panicot-Dubois, Laurence; Dubois, Christophe

    2016-04-01

    Cancer-associated venous thromboembolism (VTE) constitutes the second cause of death after cancer. Many risk factors for cancer-associated VTE have been identified, among them soluble tissue factor and microparticles (MPs). Few data are available about the implication of MPs in cancer associated-VTE through animal model of cancer. The objective of the present review was to report the state of the current literature about MPs and cancer-associated VTE in animal model of cancer. Fourteen series have reported the role of MPs in cancer-associated VTE, through three main mouse models: ectopic or orthotopic tumor induction, experimental metastasis by intravenous injection of tumor cells into the lateral tail vein of the mouse. Pancreatic cancer is the most used animal model, due to its high rate of cancer-associated VTE. All the series reported that tumor cell-derived MPs can promote thrombus formation in TF-dependent manner. Some authors reported also the implication of phosphatidylserine and PSGL1 in the generation of thrombin. Moreover, MPs seem to be implicated in cancer progression through a coagulation-dependent mechanism secondary to thrombocytosis, or a mechanism implicating the regulation of the immune response. For these reasons, few authors have reported that antiplatelet and anticoagulant treatments may prevent tumor progression and the formation of metastases in addition of coagulopathy. © 2016 Elsevier Ltd. All rights reserved.

  4. Influence of sedation and data acquisition method on tracer uptake in animal models: [{sup 123}I]-2-iodo-L-phenylalanine in pentobarbital-sedated tumor-bearing athymic mice

    Energy Technology Data Exchange (ETDEWEB)

    Kersemans, Veerle [Laboratory for Radiopharmacy, Universiteit Gent, Harelbekestraat 72 B-9000 Gent (Belgium)]. E-mail: veerle.kersemans@utoronto.ca; Spiegeleer, Bart de [Laboratory for Radiopharmacy, Universiteit Gent, Harelbekestraat 72 B-9000 Gent (Belgium); Mertens, John [Laboratory for Medical Imaging and Physics, Vrije Universiteit Brussel, Laarbecklaan 103 B-1090 Brussel (Belgium); Slegers, Guido [Laboratory for Radiopharmacy, Universiteit Gent, Harelbekestraat 72 B-9000 Gent (Belgium)

    2006-01-15

    Objectives: To minimize movement artifacts during tracer imaging studies, the animals are generally sedated. Although many reports describe the effect of barbiturates on brain function, less is published about the general impact on the extracerebral metabolism and tracer biodistribution. This report describes the influence of pentobarbital on tumor uptake of [{sup 123}I]-2-iodo-L-phenylalanine ([{sup 123}I]-2I-L-PA) using dissection and nuclear imaging. Methods: R1M tumor-bearing athymic mice were divided into two populations: untreated and pentobarbital-treated. Each group was subjected to dynamic and static planar imaging and organ dissection after [{sup 123}I]-2I-L-PA injection. Two-compartment blood modeling was performed. Analysis of variance (ANOVA), t test and clustered boxplot analyses were used to compare the results between the treatment groups and between the data acquisition methods. Results: Two-compartment blood modeling demonstrated that pentobarbital decreased the elimination velocity and the distribution toward the peripheral compartment. Both observations lead to higher blood pool and kidney activities after administering pentobarbital. The dependence of the differential absorption/differential uptake ratio results on the factors organ, method and treatment (3-factor ANOVA) demonstrated that all factors had a significant effect. Moreover, a significant effect for method and treatment was observed for each individual organ, and the ratio of tumor to background showed additionally an ordinal interaction between the latter two factors. Although the tumor uptake values were lower when using sedation and nuclear imaging, the tumor could still be visualized. Conclusions: An effect of sedation treatment and data acquisition method was demonstrated for 2-iodo-phenylalanine, currently under development as tumor tracer. It is recommended that animal experiments should include quantitative investigation of sedation and the data acquisition method.

  5. Animal Models of Neuropsychiatric Disorders

    Science.gov (United States)

    Nestler, Eric J.; Hyman, Steven E.

    2013-01-01

    Modeling of human neuropsychiatric disorders in animals is extremely challenging given the subjective nature of many key symptoms, the lack of biomarkers and objective diagnostic tests, and the early state of the relevant neurobiology and genetics. Nonetheless, progress in understanding pathophysiology and in treatment development would benefit greatly from improved animal models. Here we review the current state of animal models of mental illness, with a focus on schizophrenia, depression, and bipolar disorder. We argue for areas of focus that might increase the likelihood of creating more useful models, at least for some disorders, and for explicit guidelines when animal models are reported. PMID:20877280

  6. Synthesis, analysis, purification and biodistribution in an animal model of radiopharmaceutical 177Lu3+ -dotatato for diagnostic and therapeutic use in neuroendocrine tumors

    International Nuclear Information System (INIS)

    Caldeira Filho, Jose de Souza

    2009-01-01

    The aim of this work was to propose rationalization in the synthesis, analysis and purification of radiopharmaceutical 177 Lu 3+ - DOTATATO for diagnostic and therapeutic use in neuroendocrine tumors, as well as for evaluation g biodistribution of this radiopharmaceutical an animal-mode. The complexation reaction for the synthesis of radiopharmaceutical was carried out in ammonium acetate buffer 0.5 M, p H 7.0, for 30 minutes at 95 deg C. The radiochemical purity was > 95%, according to analysis by chromatography in ITLC-SG, when using the sodium citrate buffer 0,1 M, p H 5.0, as the mobile phase. The molar-limit ratio 177 Lu 3+ :DOTATATO, in ammonium acetate buffer 0.5 M, p H 7.0, for 30 minutes at 95 deg C, was dependent on the specific activity and origin of the radioisotope, this being 1:3.5 (370 MBq : 26μg) for that from the Oak Ridge National Laboratory /USA, and 1:16 (370 MBq: 11.8 μg) for that from Nuclear Analytical and Medical Services/Holland, when considering a decay of five days from the production date of te radioisotopes. This rationalization in the synthesis of radiopharmaceutical 177 Lu 3+ - DOTATATO permits high economy in production costs. Chemical studies on the synthesis of radiopharmaceuticals also placed in evidence the interference of 177 Hf 4+ , the decay product of 177 Lu 3= , as the 177 Lu 3= competitor for DOTATATO. Radiopharmaceutical preparation proved to be stable during 24 hours, at an activity rate of 2775 MBq, with the addition of 0.6 mg/mL of gentisic acid and when kept in dry ice. In biodistribution studies on Swiss and Nuce mice, the specificity of radiopharmaceutical for somatostatin positive-receptor tissues, such as the pancreas, stomach, lungs, adrenal glands, kidneys and the cell tumor AR42J was demonstrated. (author)

  7. ANIMAL MODELS FOR IMMUNOTOXICITY

    Science.gov (United States)

    Greater susceptibility to infection is a hallmark of compromised immune function in humans and animals, and is often considered the benchmark against which the predictive value of immune function tests are compared. This focus of this paper is resistance to infection with the pa...

  8. Cyclophosphamide Enhances Human Tumor Growth in Nude Rat Xenografted Tumor Models

    Directory of Open Access Journals (Sweden)

    Yingjen Jeffrey Wu

    2009-02-01

    Full Text Available The effect of the immunomodulatory chemotherapeutic agent cyclophosphamide (CTX on tumor growth was investigated in primary and metastatic intracerebral and subcutaneous rat xenograft models. Nude rats were treated with CTX (100 mg/kg, intraperitoneally 24 hours before human ovarian carcinoma (SKOV3, small cell lung carcinoma (LX-1 SCLC, and glioma (UW28, U87MG, and U251 tumor cells were inoculated subcutaneously, intraperitoneally, or in the right cerebral hemisphere or were infused into the right internal carotid artery. Tumor development was monitored and recorded. Potential mechanisms were further investigated. Only animals that received both CTX and Matrigel showed consistent growth of subcutaneous tumors. Cyclophosphamide pretreatment increased the percentage (83.3% vs 0% of animals showing intraperitoneal tumors. In intracerebral implantation tumor models, CTX pretreatment increased the tumor volume and the percentage of animals showing tumors. Cyclophosphamide increased lung carcinoma bone and facial metastases after intra-arterial injection, and 20% of animals showed brain metastases. Cyclophosphamide transiently decreased nude rat white blood cell counts and glutathione concentration, whereas serum vascular endothelial growth factor was significantly elevated. Cyclophosphamide also increased CD31 reactivity, a marker of vascular endothelium, and macrophage (CD68-positive infiltration into glioma cell-inoculated rat brains. Cyclophosphamide may enhance primary and metastatic tumor growth through multiple mechanisms, including immune modulation, decreased response to oxidative stress, increased tumor vascularization, and increased macrophage infiltration. These findings may be clinically relevant because chemotherapy may predispose human cancer subjects to tumor growth in the brain or other tissues.

  9. Photoradiation therapy of animal tumors and nasopharyngeal carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, S.P.; Tao, Z.D.; Xiao, J.Y.; Peng, Y.Y.; Yang, Y.H.; Zeng, Q.S.; Liu, Z.W. (First Affiliated Hospital, Changsha (China))

    1990-06-01

    Both animal tumors and human nasopharyngeal carcinoma were submitted to a photoradiation therapy (PRT) trial in order to determine the efficacy and side effects of PRT, as well as to elucidate its mechanism of cytotoxicity. In animal tumors, the inhibition rate was 70%, and of 20 patients, eight achieved complete remission, and ten, significant remission, with an overall response rate of 90%. The blood picture and the values of serum IgG, IgM, IgA, and C3 all remained stable post-PRT. Only three patients developed mild generalized skin photosensitive reactions, and these did not affect subsequent treatment. There was no immunosuppressive effect as evidenced by a tritium-labeled thymidine-incorporated lymphocytoblast transformation assay performed both before and after PRT. Ultrastructural studies at different time intervals after PRT highly suggested that the mitochondria and rough endoplasmic reticulum were among the first organelles to be damaged.

  10. Photoradiation therapy of animal tumors and nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Zhao, S.P.; Tao, Z.D.; Xiao, J.Y.; Peng, Y.Y.; Yang, Y.H.; Zeng, Q.S.; Liu, Z.W.

    1990-01-01

    Both animal tumors and human nasopharyngeal carcinoma were submitted to a photoradiation therapy (PRT) trial in order to determine the efficacy and side effects of PRT, as well as to elucidate its mechanism of cytotoxicity. In animal tumors, the inhibition rate was 70%, and of 20 patients, eight achieved complete remission, and ten, significant remission, with an overall response rate of 90%. The blood picture and the values of serum IgG, IgM, IgA, and C3 all remained stable post-PRT. Only three patients developed mild generalized skin photosensitive reactions, and these did not affect subsequent treatment. There was no immunosuppressive effect as evidenced by a tritium-labeled thymidine-incorporated lymphocytoblast transformation assay performed both before and after PRT. Ultrastructural studies at different time intervals after PRT highly suggested that the mitochondria and rough endoplasmic reticulum were among the first organelles to be damaged

  11. In silico modeling for tumor growth visualization.

    Science.gov (United States)

    Jeanquartier, Fleur; Jean-Quartier, Claire; Cemernek, David; Holzinger, Andreas

    2016-08-08

    Cancer is a complex disease. Fundamental cellular based studies as well as modeling provides insight into cancer biology and strategies to treatment of the disease. In silico models complement in vivo models. Research on tumor growth involves a plethora of models each emphasizing isolated aspects of benign and malignant neoplasms. Biologists and clinical scientists are often overwhelmed by the mathematical background knowledge necessary to grasp and to apply a model to their own research. We aim to provide a comprehensive and expandable simulation tool to visualizing tumor growth. This novel Web-based application offers the advantage of a user-friendly graphical interface with several manipulable input variables to correlate different aspects of tumor growth. By refining model parameters we highlight the significance of heterogeneous intercellular interactions on tumor progression. Within this paper we present the implementation of the Cellular Potts Model graphically presented through Cytoscape.js within a Web application. The tool is available under the MIT license at https://github.com/davcem/cpm-cytoscape and http://styx.cgv.tugraz.at:8080/cpm-cytoscape/ . In-silico methods overcome the lack of wet experimental possibilities and as dry method succeed in terms of reduction, refinement and replacement of animal experimentation, also known as the 3R principles. Our visualization approach to simulation allows for more flexible usage and easy extension to facilitate understanding and gain novel insight. We believe that biomedical research in general and research on tumor growth in particular will benefit from the systems biology perspective.

  12. Animal Models for Candidiasis

    Science.gov (United States)

    Conti, Heather R.; Huppler, Anna R.; Whibley, Natasha; Gaffen, Sarah L.

    2014-01-01

    Multiple forms of candidiasis are clinically important in humans. Established murine models of disseminated, oropharyngeal, vaginal, and cutaneous candidiasis caused by Candida albicans are described in this unit. Detailed materials and methods for C. albicans growth and detection are also described. PMID:24700323

  13. Animal Models of Bacterial Keratitis

    Science.gov (United States)

    Marquart, Mary E.

    2011-01-01

    Bacterial keratitis is a disease of the cornea characterized by pain, redness, inflammation, and opacity. Common causes of this disease are Pseudomonas aeruginosa and Staphylococcus aureus. Animal models of keratitis have been used to elucidate both the bacterial factors and the host inflammatory response involved in the disease. Reviewed herein are animal models of bacterial keratitis and some of the key findings in the last several decades. PMID:21274270

  14. Animal models for human diseases.

    Science.gov (United States)

    Rust, J H

    1982-01-01

    The use of animal models for the study of human disease is, for the most part, a recent development. This discussion of the use of animal models for human diseases directs attention to the sterile period, early advances, some personal experiences, the human as the model, biological oddities among common laboratory animals, malignancies in laboratory animals, problems created by federal regulations, cancer tests with animals, and what the future holds in terms of the use of animal models as an aid to understanding human disease. In terms of early use of animal models, there was a school of rabbis, some of whom were also physicians, in Babylon who studied and wrote extensively on ritual slaughter and the suitability of birds and beasts for food. Considerable detailed information on animal pathology, physiology, anatomy, and medicine in general can be found in the Soncino Babylonian Talmudic Translations. The 1906 edition of the "Jewish Encyclopedia," has been a rich resource. Although it has not been possible to establish what diseases of animals were studied and their relationship to the diseases of humans, there are fascinating clues to pursue, despite the fact that these were sterile years for research in medicine. The quotation from the Talmud is of interest: "The medical knowledge of the Talmudist was based upon tradition, the dissection of human bodies, observation of disease and experiments upon animals." A bright light in the lackluster years of medical research was provided by Galen, considered the originator of research in physiology and anatomy. His dissection of animals and work on apes and other lower animals were models for human anatomy and physiology and the bases for many treatises. Yet, Galen never seemed to suggest that animals could serve as models for human diseases. Most early physicians who can be considered to have been students of disease developed their medical knowledge by observing the sick under their care. 1 early medical investigator

  15. Animal models in myopia research.

    Science.gov (United States)

    Schaeffel, Frank; Feldkaemper, Marita

    2015-11-01

    Our current understanding of the development of refractive errors, in particular myopia, would be substantially limited had Wiesel and Raviola not discovered by accident that monkeys develop axial myopia as a result of deprivation of form vision. Similarly, if Josh Wallman and colleagues had not found that simple plastic goggles attached to the chicken eye generate large amounts of myopia, the chicken model would perhaps not have become such an important animal model. Contrary to previous assumptions about the mechanisms of myopia, these animal models suggested that eye growth is visually controlled locally by the retina, that an afferent connection to the brain is not essential and that emmetropisation uses more sophisticated cues than just the magnitude of retinal blur. While animal models have shown that the retina can determine the sign of defocus, the underlying mechanism is still not entirely clear. Animal models have also provided knowledge about the biochemical nature of the signal cascade converting the output of retinal image processing to changes in choroidal thickness and scleral growth; however, a critical question was, and still is, can the results from animal models be applied to myopia in children? While the basic findings from chickens appear applicable to monkeys, some fundamental questions remain. If eye growth is guided by visual feedback, why is myopic development not self-limiting? Why does undercorrection not arrest myopic progression even though positive lenses induce myopic defocus, which leads to the development of hyperopia in emmetropic animals? Why do some spectacle or contact lens designs reduce myopic progression and others not? It appears that some major differences exist between animals reared with imposed defocus and children treated with various optical corrections, although without the basic knowledge obtained from animal models, we would be lost in an abundance of untestable hypotheses concerning human myopia. © 2015 Optometry

  16. Combined MR and Optical Imaging System for Noninvasive Tumor Characterization and Quantification of Oxygenation Gain Factor in a Breast Cancer Animal Model

    National Research Council Canada - National Science Library

    Shafiiha, Roshanak

    2007-01-01

    This study proposes to modify and improve an existing MR-compatible optical tomography system that is used for non-invasive tumor characterization and provides higher sensitivity and specificity for cancer imaging...

  17. Towards PDT with Genetically Encoded Photosensitizer KillerRed: A Comparison of Continuous and Pulsed Laser Regimens in an Animal Tumor Model.

    Directory of Open Access Journals (Sweden)

    Marina Shirmanova

    Full Text Available The strong phototoxicity of the red fluorescent protein KillerRed allows it to be considered as a potential genetically encoded photosensitizer for the photodynamic therapy (PDT of cancer. The advantages of KillerRed over chemical photosensitizers are its expression in tumor cells transduced with the appropriate gene and direct killing of cells through precise damage to any desired cell compartment. The ability of KillerRed to affect cell division and to induce cell death has already been demonstrated in cancer cell lines in vitro and HeLa tumor xenografts in vivo. However, the further development of this approach for PDT requires optimization of the method of treatment. In this study we tested the continuous wave (593 nm and pulsed laser (584 nm, 10 Hz, 18 ns modes to achieve an antitumor effect. The research was implemented on CT26 subcutaneous mouse tumors expressing KillerRed in fusion with histone H2B. The results showed that the pulsed mode provided a higher rate of photobleaching of KillerRed without any temperature increase on the tumor surface. PDT with the continuous wave laser was ineffective against CT26 tumors in mice, whereas the pulsed laser induced pronounced histopathological changes and inhibition of tumor growth. Therefore, we selected an effective regimen for PDT when using the genetically encoded photosensitizer KillerRed and pulsed laser irradiation.

  18. Animal models of pituitary neoplasia

    OpenAIRE

    Lines, K.E.; Stevenson, M.; Thakker, R.V.

    2016-01-01

    Pituitary neoplasias can occur as part of a complex inherited disorder, or more commonly as sporadic (non-familial) disease. Studies of the molecular and genetic mechanisms causing such pituitary tumours have identified dysregulation of >35 genes, with many revealed by studies in mice, rats and zebrafish. Strategies used to generate these animal models have included gene knockout, gene knockin and transgenic over-expression, as well as chemical mutagenesis and drug induction. These animal mod...

  19. XX. Animal models of pneumocystosis

    DEFF Research Database (Denmark)

    Dei-Cas, E.; Brun-Pascaud, M.; Bille-Hansen, Vivi

    1998-01-01

    As in vitro culture systems allowing to isolate Pneumocystis samples from patients or other mammal hosts are still not available, animal models have critical importance in Pneumocystis research. The parasite was reported in numerous mammals but P. carinii pneumonia (PCP) experimental models were...... a source of parasites taxonomically related to P. carinii sp. f hominis. Moreover, primates might be used as experimental hosts to human Pneumocystis. A marked variability of parasite levels among corticosteroid-treated animals and the fact that the origin of the parasite strain remains unknown......, are important drawbacks of the corticosteroid-treated models. For these reasons, inoculated animal models of PCP were developed. The intratracheal inoculation of lung homogenates containing viable parasites in corticosteroid-treated non-latently infected rats resulted in extensive, reproducible Pneumocystis...

  20. Animal models of pituitary neoplasia

    Science.gov (United States)

    Lines, K.E.; Stevenson, M.; Thakker, R.V.

    2016-01-01

    Pituitary neoplasias can occur as part of a complex inherited disorder, or more commonly as sporadic (non-familial) disease. Studies of the molecular and genetic mechanisms causing such pituitary tumours have identified dysregulation of >35 genes, with many revealed by studies in mice, rats and zebrafish. Strategies used to generate these animal models have included gene knockout, gene knockin and transgenic over-expression, as well as chemical mutagenesis and drug induction. These animal models provide an important resource for investigation of tissue-specific tumourigenic mechanisms, and evaluations of novel therapies, illustrated by studies into multiple endocrine neoplasia type 1 (MEN1), a hereditary syndrome in which ∼30% of patients develop pituitary adenomas. This review describes animal models of pituitary neoplasia that have been generated, together with some recent advances in gene editing technologies, and an illustration of the use of the Men1 mouse as a pre clinical model for evaluating novel therapies. PMID:26320859

  1. Animal welfare and use of silkworm as a model animal.

    Science.gov (United States)

    Sekimizu, N; Paudel, A; Hamamoto, H

    2012-08-01

    Sacrificing model animals is required for developing effective drugs before being used in human beings. In Japan today, at least 4,210,000 mice and other mammals are sacrificed to a total of 6,140,000 per year for the purpose of medical studies. All the animals treated in Japan, including test animals, are managed under control of "Act on Welfare and Management of Animals". Under the principle of this Act, no person shall kill, injure, or inflict cruelty on animals without due cause. "Animal" addressed in the Act can be defined as a "vertebrate animal". If we can make use of invertebrate animals in testing instead of vertebrate ones, that would be a remarkable solution for the issue of animal welfare. Furthermore, there are numerous advantages of using invertebrate animal models: less space and small equipment are enough for taking care of a large number of animals and thus are cost-effective, they can be easily handled, and many biological processes and genes are conserved between mammals and invertebrates. Today, many invertebrates have been used as animal models, but silkworms have many beneficial traits compared to mammals as well as other insects. In a Genome Pharmaceutical Institute's study, we were able to achieve a lot making use of silkworms as model animals. We would like to suggest that pharmaceutical companies and institutes consider the use of the silkworm as a model animal which is efficacious both for financial value by cost cutting and ethical aspects in animals' welfare.

  2. Small animal models of xenotransplantation.

    Science.gov (United States)

    Wang, Hao

    2012-01-01

    Organ transplantation has become a successful and acceptable treatment for end-stage organ failure. Such success has allowed transplant patients to resume a normal lifestyle. The demands for transplantation have been steadily increasing, as more patients and new diseases are being deemed eligible for treatment via transplantation. However, it is clear that human organs will never meet the increasing demand of transplantation. Therefore, scientists must continue to pursue alternative therapies and explore new treatments to meet the growing demand for the limited number of organs available. Transplanting organs from animals into humans (xenotransplantation) is one such therapy. The observed enthusiasm for xenotransplantation, irrespective of the severe shortage of human organs and tissues available for transplantation, can be said to stem from at least two factors. First, there is the possibility that animal organs and tissues might be less susceptible than those of humans to the recurrence of disease processes. Second, a xenograft might be used as a vehicle for introducing novel genes or biochemical processes which could be of therapeutic value for the transplant recipient.To date, millions of lives have been saved by organ transplantation. These remarkable achievements would have been impossible without experimental transplantation research in animal models. Presently, more than 95% of organ transplantation research projects are carried out using rodents, such as rats and mice. The key factor to ensure the success of these experiments lies in state-of-the art experimental surgery. Small animal models offer unique advantages for the mechanistic study of xenotransplantation rejection. Currently, multiple models have been developed for investigating the different stages of immunological barriers in xenotransplantation. In this chapter, we describe six valuable small animal models that have been used in xenotransplantation research. The methodology for the small animal

  3. Anesthesia condition for 18F-FDG imaging of lung metastasis tumors using small animal PET

    International Nuclear Information System (INIS)

    Woo, Sang-Keun; Lee, Tae Sup; Kim, Kyeong Min; Kim, June-Youp; Jung, Jae Ho; Kang, Joo Hyun; Cheon, Gi Jeong; Choi, Chang Woon; Lim, Sang Moo

    2008-01-01

    Small animal positron emission tomography (PET) with 18 F-FDG has been increasingly used for tumor imaging in the murine model. The aim of this study was to establish the anesthesia condition for imaging of lung metastasis tumor using small animal 18 F-FDG PET. Methods: To determine the impact of anesthesia on 18 F-FDG distribution in normal mice, five groups were studied under the following conditions: no anesthesia, ketamine and xylazine (Ke/Xy), 0.5% isoflurane (Iso 0.5), 1% isoflurane (Iso 1) and 2% isoflurane (Iso 2). The ex vivo counting, standard uptake value (SUV) image and glucose SUV of 18 F-FDG in various tissues were evaluated. The 18 F-FDG images in the lung metastasis tumor model were obtained under no anesthesia, Ke/Xy and Iso 0.5, and registered with CT image to clarify the tumor region. Results: Blood glucose concentration and muscle uptake of 18 F-FDG in the Ke/Xy group markedly increased more than in the other groups. The Iso 2 group increased 18 F-FDG uptake in heart compared with the other groups. The Iso 0.5 anesthesized group showed the lowest 18 F-FDG uptake in heart and chest wall. The small size of lung metastasis tumor (2 mm) was clearly visualized by 18 F-FDG image with the Iso 0.5 anesthesia. Conclusion: Small animal 18 F-FDG PET imaging with Iso 0.5 anesthesia was appropriate for the detection of lung metastasis tumor. To acquire 18 F-FDG PET images with small animal PET, the type and level of anesthetic should be carefully considered to be suitable for the visualization of target tissue in the experimental model

  4. 12/15 lipoxygenase regulation of colorectal tumorigenesis is determined by the relative tumor levels of its metabolite 12-HETE and 13-HODE in animal models

    OpenAIRE

    Chang, Jian; Jiang, Li; Wang, Yinqiu; Yao, Bing; Yang, Shilin; Zhang, Bixiang; Zhang, Ming-Zhi

    2014-01-01

    Colorectal cancer (CRC) continues to be a major cause of morbidity and mortality. The arachidonic acid (AA) pathway and linoleic acid (LA) pathway have been implicated as important contributors to CRC development and growth. Human 15-lipoxygenase 1 (15-LOX-1) converts LA to anti-tumor 13-S-hydroxyoctadecadienoic acid (13-HODE)and 15-LOX-2 converts AA to 15-hydroxyeicosatetraenoic acid (15-HETE). In addition, human 12-LOX metabolizes AA to pro-tumor 12-HETE. In rodents, the function of 12-LOX ...

  5. Effects of experimental radiotherapy and hyperthermia on tumors and normal tissues in small animals

    International Nuclear Information System (INIS)

    Wondergem, J.

    1985-01-01

    Experiments on responses of tumors, implanted subcutaneously in the leg, to irradiation alone or combined with heat are reported. The influence of factors modifying the fraction of hypoxic cells (e.g. anesthesia of the animal and tumor volume) is also discussed. The radiosensitivity of developing lung tumors was examined for spontaneous as well as for artificial lung metastases. Both experimental tumor models were compared with regard to their value in experimental radiotherapy. Data obtained on the response of artificial metastases and lung tissue to combined treatment with irradiation and several drugs are presented. Data on damage of the mouse foot, as a result of heat and/or irradiation treatments are presented. In particular the influence of thermotolerance on thermal enhancement of the radiation induced skin reaction was studied. Tolerance of the skin of previously irradiated mice to retreatment with irradiation, to hyperthermia alone and combined with X-rays was assessed. (Auth.)

  6. Myeloid cell leukemia-1 is a key molecular target for mithramycin A-induced apoptosis in androgen-independent prostate cancer cells and a tumor xenograft animal model.

    Science.gov (United States)

    Choi, Eun-Sun; Jung, Ji-Youn; Lee, Jin-Seok; Park, Jong-Hwan; Cho, Nam-Pyo; Cho, Sung-Dae

    2013-01-01

    Mithramycin A (Mith) is a natural polyketide that has been used in multiple areas of research including apoptosis of various cancer cells. Here, we examined the critical role of Mith in apoptosis and its molecular mechanism in DU145 and PC3 prostate cancer cells and tumor xenografts. Mith decreased cell growth and induced apoptosis in DU145 and PC-3 cells. Myeloid cell leukemia-1 (Mcl-1) was over-expressed in both cell lines compared to RWPE1 cells. Mith inhibited Mcl-1 protein expression in both cells, but only altered Mcl-1 mRNA levels in PC-3 cells. We also found that Mith reduced Mcl-1 protein levels through both proteasome-dependent protein degradation and the inhibition of protein synthesis in DU145 cells. Studies using siRNA confirmed that the knockdown of Mcl-1 induced apoptosis. Mith significantly suppressed TPA-induced neoplastic cell transformation through the down-regulation of the Mcl-1 protein in JB6 cells, and suppressed the transforming activity of both cell types. Mith also inhibited tumor growth and Mcl-1 levels, in addition to inducing apoptosis, in athymic nude mice bearing DU145 cell xenografts without affecting five normal organs. Therefore, Mith inhibits cell growth and induces apoptosis by suppressing Mcl-1 in both prostate cancer cells and xenograft tumors, and thus is a potent anticancer drug candidate for prostate cancer. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  7. Animal models for auditory streaming

    Science.gov (United States)

    Itatani, Naoya

    2017-01-01

    Sounds in the natural environment need to be assigned to acoustic sources to evaluate complex auditory scenes. Separating sources will affect the analysis of auditory features of sounds. As the benefits of assigning sounds to specific sources accrue to all species communicating acoustically, the ability for auditory scene analysis is widespread among different animals. Animal studies allow for a deeper insight into the neuronal mechanisms underlying auditory scene analysis. Here, we will review the paradigms applied in the study of auditory scene analysis and streaming of sequential sounds in animal models. We will compare the psychophysical results from the animal studies to the evidence obtained in human psychophysics of auditory streaming, i.e. in a task commonly used for measuring the capability for auditory scene analysis. Furthermore, the neuronal correlates of auditory streaming will be reviewed in different animal models and the observations of the neurons’ response measures will be related to perception. The across-species comparison will reveal whether similar demands in the analysis of acoustic scenes have resulted in similar perceptual and neuronal processing mechanisms in the wide range of species being capable of auditory scene analysis. This article is part of the themed issue ‘Auditory and visual scene analysis’. PMID:28044022

  8. Animal Models of Cancer-Associated Hypercalcemia.

    Science.gov (United States)

    Kohart, Nicole A; Elshafae, Said M; Breitbach, Justin T; Rosol, Thomas J

    2017-04-13

    Cancer-associated hypercalcemia (CAH) is a frequently-occurring paraneoplastic syndrome that contributes to substantial patient morbidity and occurs in both humans and animals. Patients with CAH are often characterized by markedly elevated serum calcium concentrations that result in a range of clinical symptoms involving the nervous, gastrointestinal and urinary systems. CAH is caused by two principle mechanisms; humorally-mediated and/or through local osteolytic bone metastasis resulting in excessive calcium release from resorbed bone. Humoral hypercalcemia of malignancy (HHM) is the most common mechanism and is due to the production and release of tumor-associated cytokines and humoral factors, such as parathyroid hormone-related protein (PTHrP), that act at distant sites to increase serum calcium concentrations. Local osteolytic hypercalcemia (LOH) occurs when primary or metastatic bone tumors act locally by releasing factors that stimulate osteoclast activity and bone resorption. LOH is a less frequent cause of CAH and in some cases can induce hypercalcemia in concert with HHM. Rarely, ectopic production of parathyroid hormone has been described. PTHrP-mediated hypercalcemia is the most common mechanism of CAH in human and canine malignancies and is recognized in other domestic species. Spontaneous and experimentally-induced animal models have been developed to study the mechanisms of CAH. These models have been essential for the evaluation of novel approaches and adjuvant therapies to manage CAH. This review will highlight the comparative aspects of CAH in humans and animals with a discussion of the available animal models used to study the pathogenesis of this important clinical syndrome.

  9. Animal models of papillomavirus pathogenesis.

    Science.gov (United States)

    Campo, M Saveria

    2002-11-01

    Tumorigenesis due to papillomavirus (PV) infection was first demonstrated in rabbits and cattle early last century. Despite the evidence obtained in animals, the role of viruses in human cancer was dismissed as irrelevant. It took a paradigm shift in the late 1970s for some viruses to be recognised as 'tumour viruses' in humans, and in 1995, more than 60 years after Rous's first demonstration of CRPV oncogenicity, WHO officially declared that 'HPV-16 and HPV-18 are carcinogenic to humans'. Experimental studies with animal PVs have been a determining factor in this decision. Animal PVs have been studied both as agents of disease in animals and as models of human PV infection. In addition to the study of PV infection in whole animals, in vitro studies with animal PV proteins have contributed greatly to the understanding of the mechanisms of cell transformation. Animal PVs cause distressing diseases in both farm and companion animals, such as teat papillomatosis in cattle, equine sarcoids and canine oral papillomatosis and there is an urgent need to understand the pathogenesis of these problematic infections. Persistent and florid teat papillomatosis in cows can lead to mastitis, prevent the suckling of calves and make milking impossible; heavily affected animals are culled and so occasionally are whole herds. Equine sarcoids are often recurrent and untreatable and lead to loss of valuable animals. Canine oral papillomatosis can be very extensive and persistent and lead to great distress. Thus the continuing research in the biology of animal PVs is amply justified. BPVs and CRPV have been for many years the model systems with which to study the biology of HPV. Induction of papillomas and their neoplastic progression has been experimentally demonstrated and reproduced in cattle and rabbits, and virus-cofactor interactions have been elucidated in these systems. With the advancements in molecular and cell culture techniques, the direct study of HPV has become less

  10. Animal Models of Zika Virus

    Science.gov (United States)

    Bradley, Michael P; Nagamine, Claude M

    2017-01-01

    Zika virus has garnered great attention over the last several years, as outbreaks of the disease have emerged throughout the Western Hemisphere. Until quite recently Zika virus was considered a fairly benign virus, with limited clinical severity in both people and animals. The size and scope of the outbreak in the Western Hemisphere has allowed for the identification of severe clinical disease that is associated with Zika virus infection, most notably microcephaly among newborns, and an association with Guillian–Barré syndrome in adults. This recent association with severe clinical disease, of which further analysis strongly suggested causation by Zika virus, has resulted in a massive increase in the amount of both basic and applied research of this virus. Both small and large animal models are being used to uncover the pathogenesis of this emerging disease and to develop vaccine and therapeutic strategies. Here we review the animal-model–based Zika virus research that has been performed to date. PMID:28662753

  11. XX. Animal models of pneumocystosis

    DEFF Research Database (Denmark)

    Dei-Cas, E.; Brun-Pascaud, M.; Bille-Hansen, Vivi

    1998-01-01

    As in vitro culture systems allowing to isolate Pneumocystis samples from patients or other mammal hosts are still not available, animal models have critical importance in Pneumocystis research. The parasite was reported in numerous mammals but P. carinii pneumonia (PCP) experimental models were...... the host immune response as well as Pneumocystis-surfactant interactions. Pigs and horses also develop spontaneous PCP. Treated with corticosteroids, piglets develop extensive PCP and could be used as a non-rodent model. Pneumocystis was detected in many non-human primates. Primates could represent...... a source of parasites taxonomically related to P. carinii sp. f hominis. Moreover, primates might be used as experimental hosts to human Pneumocystis. A marked variability of parasite levels among corticosteroid-treated animals and the fact that the origin of the parasite strain remains unknown...

  12. Animal models of drug addiction.

    Science.gov (United States)

    García Pardo, María Pilar; Roger Sánchez, Concepción; De la Rubia Ortí, José Enrique; Aguilar Calpe, María Asunción

    2017-09-29

    The development of animal models of drug reward and addiction is an essential factor for progress in understanding the biological basis of this disorder and for the identification of new therapeutic targets. Depending on the component of reward to be studied, one type of animal model or another may be used. There are models of reinforcement based on the primary hedonic effect produced by the consumption of the addictive substance, such as the self-administration (SA) and intracranial self-stimulation (ICSS) paradigms, and there are models based on the component of reward related to associative learning and cognitive ability to make predictions about obtaining reward in the future, such as the conditioned place preference (CPP) paradigm. In recent years these models have incorporated methodological modifications to study extinction, reinstatement and reconsolidation processes, or to model specific aspects of addictive behavior such as motivation to consume drugs, compulsive consumption or drug seeking under punishment situations. There are also models that link different reinforcement components or model voluntary motivation to consume (two-bottle choice, or drinking in the dark tests). In short, innovations in these models allow progress in scientific knowledge regarding the different aspects that lead individuals to consume a drug and develop compulsive consumption, providing a target for future treatments of addiction.

  13. Modelling group dynamic animal movement

    DEFF Research Database (Denmark)

    Langrock, Roland; Hopcraft, J. Grant C.; Blackwell, Paul G.

    2014-01-01

    in non-ideal scenarios, we show that generally the estimation of models of this type is both feasible and ecologically informative. We illustrate the approach using real movement data from 11 reindeer (Rangifer tarandus). Results indicate a directional bias towards a group centroid for reindeer......Group dynamic movement is a fundamental aspect of many species' movements. The need to adequately model individuals' interactions with other group members has been recognised, particularly in order to differentiate the role of social forces in individual movement from environmental factors. However......, to date, practical statistical methods which can include group dynamics in animal movement models have been lacking. We consider a flexible modelling framework that distinguishes a group-level model, describing the movement of the group's centre, and an individual-level model, such that each individual...

  14. Response of the tumor and organs of the tumor-bearing animal to the action of an ionizing radiation

    International Nuclear Information System (INIS)

    Burlakova, E.B.; Gaintseva, V.D.; Pal'mina, N.P.; Sezina, N.P.

    1977-01-01

    Changes in the antioxigenic activity (AOA) of the liver of the tumor-bearing animals and the tumor have been studied after a single whole-body exposure of animals to a dose of 600 R. AOA of the liver of animals having hepatoma 22-a and Ehrlich ascites tumor (EAT) was found to decrease immediately after irradiation while that of the tumor itself can both increase (hepatoma 22-a) and decrease (EAT). Proceeding from the assumption that AOA is connected with tissue radiosensitivity it is suggested that the observed variations in the response of tumor cells and normal tissue to the action of ionizing radiation should be taken into account when developing the schemes of radiation effect on the tumor

  15. Experimental rat lung tumor model with intrabronchial tumor cell implantation.

    Science.gov (United States)

    Gomes Neto, Antero; Simão, Antônio Felipe Leite; Miranda, Samuel de Paula; Mourão, Lívia Talita Cajaseiras; Bezerra, Nilfácio Prado; Almeida, Paulo Roberto Carvalho de; Ribeiro, Ronaldo de Albuquerque

    2008-01-01

    The objective of this study was to develop a rat lung tumor model for anticancer drug testing. Sixty-two female Wistar rats weighing 208 +/- 20 g were anesthetized intraperitoneally with 2.5% tribromoethanol (1 ml/100 g live weight), tracheotomized and intubated with an ultrafine catheter for inoculation with Walker's tumor cells. In the first step of the experiment, a technique was established for intrabronchial implantation of 10(5) to 5 x 10(5) tumor cells, and the tumor take rate was determined. The second stage consisted of determining tumor volume, correlating findings from high-resolution computed tomography (HRCT) with findings from necropsia and determining time of survival. The tumor take rate was 94.7% for implants with 4 x 10(5) tumor cells, HRCT and necropsia findings matched closely (r=0.953; p<0.0001), the median time of survival was 11 days, and surgical mortality was 4.8%. The present rat lung tumor model was shown to be feasible: the take rate was high, surgical mortality was negligible and the procedure was simple to perform and easily reproduced. HRCT was found to be a highly accurate tool for tumor diagnosis, localization and measurement and may be recommended for monitoring tumor growth in this model.

  16. Choline molecular imaging with small-animal PET for monitoring tumor cellular response to photodynamic therapy of cancer

    Science.gov (United States)

    Fei, Baowei; Wang, Hesheng; Wu, Chunying; Meyers, Joseph; Xue, Liang-Yan; MacLennan, Gregory; Schluchter, Mark

    2009-02-01

    We are developing and evaluating choline molecular imaging with positron emission tomography (PET) for monitoring tumor response to photodynamic therapy (PDT) in animal models. Human prostate cancer (PC-3) was studied in athymic nude mice. A second-generation photosensitizer Pc 4 was used for PDT in tumor-bearing mice. MicroPET images with 11C-choline were acquired before PDT and 48 h after PDT. Time-activity curves of 11C-choline uptake were analyzed before and after PDT. For treated tumors, normalized choline uptake decreased significantly 48 h after PDT, compared to the same tumors pre-PDT (p PET imaging with 11C-choline is sensitive to detect early tumor response to PDT in the animal model of human prostate cancer.

  17. Animal Models of Allergic Diseases

    Directory of Open Access Journals (Sweden)

    Domenico Santoro

    2014-12-01

    Full Text Available Allergic diseases have great impact on the quality of life of both people and domestic animals. They are increasing in prevalence in both animals and humans, possibly due to the changed lifestyle conditions and the decreased exposure to beneficial microorganisms. Dogs, in particular, suffer from environmental skin allergies and develop a clinical presentation which is very similar to the one of children with eczema. Thus, dogs are a very useful species to improve our understanding on the mechanisms involved in people’s allergies and a natural model to study eczema. Animal models are frequently used to elucidate mechanisms of disease and to control for confounding factors which are present in studies with patients with spontaneously occurring disease and to test new therapies that can be beneficial in both species. It has been found that drugs useful in one species can also have benefits in other species highlighting the importance of a comprehensive understanding of diseases across species and the value of comparative studies. The purpose of the current article is to review allergic diseases across species and to focus on how these diseases compare to the counterpart in people.

  18. Animal Models of Periventricular Leukomalacia

    Science.gov (United States)

    Choi, Ehn-Kyoung; Park, Dongsun; Kim, Tae Kyun; Lee, Sun Hee; Bae, Dae-Kwon; Yang, Goeun; Yang, Yun-Hui; Kyung, Jangbeen; Kim, Dajeong; Lee, Woo Ryoung; Suh, Jun-Gyo; Jeong, Eun-Suk; Kim, Seung U.

    2011-01-01

    Periventricular leukomalacia, specifically characterized as white matter injury, in neonates is strongly associated with the damage of pre-myelinating oligodendrocytes. Clinical data suggest that hypoxia-ischemia during delivery and intrauterine or neonatal infection-inflammation are important factors in the etiology of periventricular leukomalacia including cerebral palsy, a serious case exhibiting neurobehavioral deficits of periventricular leukomalacia. In order to explore the pathophysiological mechanisms of white matter injury and to better understand how infectious agents may affect the vulnerability of the immature brain to injury, novel animal models have been developed using hypoperfusion, microbes or bacterial products (lipopolysaccharide) and excitotoxins. Such efforts have developed rat models that produce predominantly white matter lesions by adopting combined hypoxia-ischemia technique on postnatal days 1-7, in which unilateral or bilateral carotid arteries of animals are occluded (ischemia) followed by 1-2 hour exposure to 6-8% oxygen environment (hypoxia). Furthermore, low doses of lipopolysaccharide that by themselves have no adverse-effects in 7-day-old rats, dramatically increase brain injury to hypoxic-ischemic challenge, implying that inflammation sensitizes the immature central nervous system. Therefore, among numerous models of periventricular leukomalacia, combination of hypoxia-ischemia-lipopolysaccharide might be one of the most-acceptable rodent models to induce extensive white matter injury and ensuing neurobehavioral deficits for the evaluation of candidate therapeutics. PMID:21826166

  19. T cell receptor (TCR-transgenic CD8 lymphocytes rendered insensitive to transforming growth factor beta (TGFβ signaling mediate superior tumor regression in an animal model of adoptive cell therapy

    Directory of Open Access Journals (Sweden)

    Quatromoni Jon G

    2012-06-01

    Full Text Available Abstract Tumor antigen-reactive T cells must enter into an immunosuppressive tumor microenvironment, continue to produce cytokine and deliver apoptotic death signals to affect tumor regression. Many tumors produce transforming growth factor beta (TGFβ, which inhibits T cell activation, proliferation and cytotoxicity. In a murine model of adoptive cell therapy, we demonstrate that transgenic Pmel-1 CD8 T cells, rendered insensitive to TGFβ by transduction with a TGFβ dominant negative receptor II (DN, were more effective in mediating regression of established B16 melanoma. Smaller numbers of DN Pmel-1 T cells effectively mediated tumor regression and retained the ability to produce interferon-γ in the tumor microenvironment. These results support efforts to incorporate this DN receptor in clinical trials of adoptive cell therapy for cancer.

  20. Animal models of RLS phenotypes.

    Science.gov (United States)

    Allen, Richard P; Donelson, Nathan C; Jones, Byron C; Li, Yuqing; Manconi, Mauro; Rye, David B; Sanyal, Subhabrata; Winkelmann, Juliane

    2017-03-01

    Restless legs syndrome (RLS) is a complex disorder that involves sensory and motor systems. The major pathophysiology of RLS is low iron concentration in the substantia nigra containing the cell bodies of dopamine neurons that project to the striatum, an area that is crucial for modulating movement. People who have RLS often present with normal iron values outside the brain; recent studies implicate several genes are involved in the syndrome. Like most complex diseases, animal models usually do not faithfully capture the full phenotypic spectrum of "disease," which is a uniquely human construct. Nonetheless, animal models have proven useful in helping to unravel the complex pathophysiology of diseases such as RLS and suggesting novel treatment paradigms. For example, hypothesis-independent genome-wide association studies (GWAS) have identified several genes as increasing the risk for RLS, including BTBD9. Independently, the murine homolog Btbd9 was identified as a candidate gene for iron regulation in the midbrain in mice. The relevance of the phenotype of another of the GWAS identified genes, MEIS1, has also been explored. The role of Btbd9 in iron regulation and RLS-like behaviors has been further evaluated in mice carrying a null mutation of the gene and in fruit flies when the BTBD9 protein is degraded. The BTBD9 and MEIS1 stories originate from human GWAS research, supported by work in a genetic reference population of mice (forward genetics) and further verified in mice, fish flies, and worms. Finally, the role of genetics is further supported by an inbred mouse strain that displays many of the phenotypic characteristics of RLS. The role of animal models of RLS phenotypes is also extended to include periodic limb movements. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Animal models and conserved processes

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    Greek Ray

    2012-09-01

    Full Text Available Abstract Background The concept of conserved processes presents unique opportunities for using nonhuman animal models in biomedical research. However, the concept must be examined in the context that humans and nonhuman animals are evolved, complex, adaptive systems. Given that nonhuman animals are examples of living systems that are differently complex from humans, what does the existence of a conserved gene or process imply for inter-species extrapolation? Methods We surveyed the literature including philosophy of science, biological complexity, conserved processes, evolutionary biology, comparative medicine, anti-neoplastic agents, inhalational anesthetics, and drug development journals in order to determine the value of nonhuman animal models when studying conserved processes. Results Evolution through natural selection has employed components and processes both to produce the same outcomes among species but also to generate different functions and traits. Many genes and processes are conserved, but new combinations of these processes or different regulation of the genes involved in these processes have resulted in unique organisms. Further, there is a hierarchy of organization in complex living systems. At some levels, the components are simple systems that can be analyzed by mathematics or the physical sciences, while at other levels the system cannot be fully analyzed by reducing it to a physical system. The study of complex living systems must alternate between focusing on the parts and examining the intact whole organism while taking into account the connections between the two. Systems biology aims for this holism. We examined the actions of inhalational anesthetic agents and anti-neoplastic agents in order to address what the characteristics of complex living systems imply for inter-species extrapolation of traits and responses related to conserved processes. Conclusion We conclude that even the presence of conserved processes is

  2. Animal models and conserved processes.

    Science.gov (United States)

    Greek, Ray; Rice, Mark J

    2012-09-10

    The concept of conserved processes presents unique opportunities for using nonhuman animal models in biomedical research. However, the concept must be examined in the context that humans and nonhuman animals are evolved, complex, adaptive systems. Given that nonhuman animals are examples of living systems that are differently complex from humans, what does the existence of a conserved gene or process imply for inter-species extrapolation? We surveyed the literature including philosophy of science, biological complexity, conserved processes, evolutionary biology, comparative medicine, anti-neoplastic agents, inhalational anesthetics, and drug development journals in order to determine the value of nonhuman animal models when studying conserved processes. Evolution through natural selection has employed components and processes both to produce the same outcomes among species but also to generate different functions and traits. Many genes and processes are conserved, but new combinations of these processes or different regulation of the genes involved in these processes have resulted in unique organisms. Further, there is a hierarchy of organization in complex living systems. At some levels, the components are simple systems that can be analyzed by mathematics or the physical sciences, while at other levels the system cannot be fully analyzed by reducing it to a physical system. The study of complex living systems must alternate between focusing on the parts and examining the intact whole organism while taking into account the connections between the two. Systems biology aims for this holism. We examined the actions of inhalational anesthetic agents and anti-neoplastic agents in order to address what the characteristics of complex living systems imply for inter-species extrapolation of traits and responses related to conserved processes. We conclude that even the presence of conserved processes is insufficient for inter-species extrapolation when the trait or response

  3. Medulloblastoma: Molecular Genetics and Animal Models

    Directory of Open Access Journals (Sweden)

    Corey Raffel

    2004-07-01

    Full Text Available Medulloblastoma is a primary brain tumor found in the cerebellum of children. The tumor occurs in association with two inherited cancer syndromes: Turcot syndrome and Gorlin syndrome. Insights into the molecular biology of the tumor have come from looking at alterations in the genes altered in these syndromes, PTC and APC, respectively. Murine models of medulloblastoma have been constructed based on these alterations. Additional murine models that, while mimicking the appearance of the human tumor, seem unrelated to the human tumor's molecular alterations have been made. In this review, the clinical picture, origin, molecular biology, murine models of medulloblastoma are discussed. Although a great deal has been discovered about this tumor, the genetic alterations responsible for tumor development in a majority of patients have yet to be described.

  4. Parathyroid diseases and animal models.

    Science.gov (United States)

    Imanishi, Yasuo; Nagata, Yuki; Inaba, Masaaki

    2012-01-01

    CIRCULATING CALCIUM AND PHOSPHATE ARE TIGHTLY REGULATED BY THREE HORMONES: the active form of vitamin D (1,25-dihydroxyvitamin D), fibroblast growth factor (FGF)-23, and parathyroid hormone (PTH). PTH acts to stimulate a rapid increment in serum calcium and has a crucial role in calcium homeostasis. Major target organs of PTH are kidney and bone. The oversecretion of the hormone results in hypercalcemia, caused by increased intestinal calcium absorption, reduced renal calcium clearance, and mobilization of calcium from bone in primary hyperparathyroidism. In chronic kidney disease, secondary hyperparathyroidism of uremia is observed in its early stages, and this finally develops into the autonomous secretion of PTH during maintenance hemodialysis. Receptors in parathyroid cells, such as the calcium-sensing receptor, vitamin D receptor, and FGF receptor (FGFR)-Klotho complex have crucial roles in the regulation of PTH secretion. Genes such as Cyclin D1, RET, MEN1, HRPT2, and CDKN1B have been identified in parathyroid diseases. Genetically engineered animals with these receptors and the associated genes have provided us with valuable information on the patho-physiology of parathyroid diseases. The application of these animal models is significant for the development of new therapies.

  5. Parathyroid diseases and animal models

    Directory of Open Access Journals (Sweden)

    Yasuo eImanishi

    2012-06-01

    Full Text Available Circulating calcium and phosphate are tightly regulated by 3 hormones: the active form of vitamin D (1,25-dihydroxyvitamin D, fibroblast growth factor (FGF-23, and parathyroid hormone (PTH. PTH acts to stimulate a rapid increment in serum calcium and has a crucial role in calcium homeostasis. Major target organs of PTH are kidney and bone. The oversecretion of the hormone results in hypercalcemia, caused by increased intestinal calcium absorption, reduced renal calcium clearance, and mobilization of calcium from bone in primary hyperparathyroidism. In chronic kidney disease, secondary hyperparathyroidism of uremia is observed in its early stages, and early stages, and this finally develops into the autonomous secretion of PTH during maintenance hemodialysis. Receptors in parathyroid cells, such as the calcium-sensing receptor, vitamin D receptor, and FGF receptor (FGFR-Klotho complex have crucial roles in the regulation of PTH secretion. Genes such as Cyclin D1, RET, MEN1, HRPT2, and CDKN1B have been identified in parathyroid diseases. Genetically engineered animals with these receptors and the associated genes have provided us with valuable information on the patho-physiology of parathyroid diseases. The application of these animal models is significant for the development of new therapies.

  6. Imaging circulating tumor cells in freely moving awake small animals using a miniaturized intravital microscope.

    Directory of Open Access Journals (Sweden)

    Laura Sarah Sasportas

    Full Text Available Metastasis, the cause for 90% of cancer mortality, is a complex and poorly understood process involving the invasion of circulating tumor cells (CTCs into blood vessels. These cells have potential prognostic value as biomarkers for early metastatic risk. But their rarity and the lack of specificity and sensitivity in measuring them render their interrogation by current techniques very challenging. How and when these cells are circulating in the blood, on their way to potentially give rise to metastasis, is a question that remains largely unanswered. In order to provide an insight into this "black box" using non-invasive imaging, we developed a novel miniature intravital microscopy (mIVM strategy capable of real-time long-term monitoring of CTCs in awake small animals. We established an experimental 4T1-GL mouse model of metastatic breast cancer, in which tumor cells express both fluorescent and bioluminescent reporter genes to enable both single cell and whole body tumor imaging. Using mIVM, we monitored blood vessels of different diameters in awake mice in an experimental model of metastasis. Using an in-house software algorithm we developed, we demonstrated in vivo CTC enumeration and computation of CTC trajectory and speed. These data represent the first reported use we know of for a miniature mountable intravital microscopy setup for in vivo imaging of CTCs in awake animals.

  7. Construction of a fusion plasmid containing the PSCA gene and cytotoxic T-lymphocyte associated antigen-4 (CTLA-4) and its anti-tumor effect in an animal model of prostate cancer.

    Science.gov (United States)

    Mai, T J; Ma, R; Li, Z; Bi, S C

    2016-10-24

    Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) is a negative regulator of T cell activation, which competes with CD28 for B7.1/B7.2 binding, and which has a greater affinity. Fusion of specific antigens to extracellular domain of CTLA4 represents a promising approach to increase the immunogenicity of DNA vaccines. In this study, we evaluated this interesting approach for CTLA4 enhancement on prostate stem cell antigen (PSCA)-specific immune responses and its anti-tumor effects in a prostate cancer mouse model. Consequently, we constructed a DNA vaccine containing the PSCA and the CTLA-4 gene. Vaccination with the CTLA4-fused DNA not only induced a much higher level of anti-PSCA antibody, but also increased PSCA-specific T cell response in mice. To evaluate the anti-tumor efficacy of the plasmids, murine models with PSCA-expressing tumors were generated. After injection of the tumor-bearing mouse model, the plasmid carrying the CTLA4 and PSCA fusion gene showed stronger inhibition of tumor growth than the plasmid expressing PSCA alone. These observations emphasize the potential of the CTLA4-fused DNA vaccine, which could represent a promising approach for tumor immunotherapy.

  8. Construction of a fusion plasmid containing the PSCA gene and cytotoxic T-lymphocyte associated antigen-4 (CTLA-4 and its anti-tumor effect in an animal model of prostate cancer

    Directory of Open Access Journals (Sweden)

    T.J. Mai

    Full Text Available Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4 is a negative regulator of T cell activation, which competes with CD28 for B7.1/B7.2 binding, and which has a greater affinity. Fusion of specific antigens to extracellular domain of CTLA4 represents a promising approach to increase the immunogenicity of DNA vaccines. In this study, we evaluated this interesting approach for CTLA4 enhancement on prostate stem cell antigen (PSCA-specific immune responses and its anti-tumor effects in a prostate cancer mouse model. Consequently, we constructed a DNA vaccine containing the PSCA and the CTLA-4 gene. Vaccination with the CTLA4-fused DNA not only induced a much higher level of anti-PSCA antibody, but also increased PSCA-specific T cell response in mice. To evaluate the anti-tumor efficacy of the plasmids, murine models with PSCA-expressing tumors were generated. After injection of the tumor-bearing mouse model, the plasmid carrying the CTLA4 and PSCA fusion gene showed stronger inhibition of tumor growth than the plasmid expressing PSCA alone. These observations emphasize the potential of the CTLA4-fused DNA vaccine, which could represent a promising approach for tumor immunotherapy.

  9. Cyclosporin safety in a simplified rat brain tumor implantation model

    Directory of Open Access Journals (Sweden)

    Francisco H. C. Felix

    2012-01-01

    Full Text Available Brain cancer is the second neurological cause of death. A simplified animal brain tumor model using W256 (carcinoma 256, Walker cell line was developed to permit the testing of novel treatment modalities. Wistar rats had a cell tumor solution inoculated stereotactically in the basal ganglia (right subfrontal caudate. This model yielded tumor growth in 95% of the animals, and showed absence of extracranial metastasis and systemic infection. Survival median was 10 days. Estimated tumor volume was 17.08±6.7 mm³ on the 7th day and 67.25±19.8 mm³ on 9th day post-inoculation. Doubling time was 24.25 h. Tumor growth induced cachexia, but no hematological or biochemical alterations. This model behaved as an undifferentiated tumor and can be promising for studying tumor cell migration in the central nervous system. Dexamethasone 3.0 mg/kg/day diminished significantly survival in this model. Cyclosporine 10 mg/kg/day administration was safely tolerated.

  10. Human tumor infiltrating lymphocytes cooperatively regulate prostate tumor growth in a humanized mouse model.

    Science.gov (United States)

    Roth, Michael D; Harui, Airi

    2015-01-01

    The complex interactions that occur between human tumors, tumor infiltrating lymphocytes (TIL) and the systemic immune system are likely to define critical factors in the host response to cancer. While conventional animal models have identified an array of potential anti-tumor therapies, mouse models often fail to translate into effective human treatments. Our goal is to establish a humanized tumor model as a more effective pre-clinical platform for understanding and manipulating TIL. The immune system in NOD/SCID/IL-2Rγnull (NSG) mice was reconstituted by the co-administration of human peripheral blood lymphocytes (PBL) or subsets (CD4+ or CD8+) and autologous human dendritic cells (DC), and animals simultaneously challenged by implanting human prostate cancer cells (PC3 line). Tumor growth was evaluated over time and the phenotype of recovered splenocytes and TIL characterized by flow cytometry and immunohistochemistry (IHC). Serum levels of circulating cytokines and chemokines were also assessed. A tumor-bearing huPBL-NSG model was established in which human leukocytes reconstituted secondary lymphoid organs and promoted the accumulation of TIL. These TIL exhibited a unique phenotype when compared to splenocytes with a predominance of CD8+ T cells that exhibited increased expression of CD69, CD56, and an effector memory phenotype. TIL from huPBL-NSG animals closely matched the features of TIL recovered from primary human prostate cancers. Human cytokines were readily detectible in the serum and exhibited a different profile in animals implanted with PBL alone, tumor alone, and those reconstituted with both. Immune reconstitution slowed but could not eliminate tumor growth and this effect required the presence of CD4+ T cell help. Simultaneous implantation of human PBL, DC and tumor results in a huPBL-NSG model that recapitulates the development of human TIL and allows an assessment of tumor and immune system interaction that cannot be carried out in humans

  11. Accuracy and reproducibility of tumor positioning during prolonged and multi-modality animal imaging studies

    International Nuclear Information System (INIS)

    Zhang Mutian; Huang Minming; Le, Carl; Zanzonico, Pat B; Ling, C Clifton; Koutcher, Jason A; Humm, John L; Claus, Filip; Kolbert, Katherine S; Martin, Kyle

    2008-01-01

    Dedicated small-animal imaging devices, e.g. positron emission tomography (PET), computed tomography (CT) and magnetic resonance imaging (MRI) scanners, are being increasingly used for translational molecular imaging studies. The objective of this work was to determine the positional accuracy and precision with which tumors in situ can be reliably and reproducibly imaged on dedicated small-animal imaging equipment. We designed, fabricated and tested a custom rodent cradle with a stereotactic template to facilitate registration among image sets. To quantify tumor motion during our small-animal imaging protocols, 'gold standard' multi-modality point markers were inserted into tumor masses on the hind limbs of rats. Three types of imaging examination were then performed with the animals continuously anesthetized and immobilized: (i) consecutive microPET and MR images of tumor xenografts in which the animals remained in the same scanner for 2 h duration, (ii) multi-modality imaging studies in which the animals were transported between distant imaging devices and (iii) serial microPET scans in which the animals were repositioned in the same scanner for subsequent images. Our results showed that the animal tumor moved by less than 0.2-0.3 mm over a continuous 2 h microPET or MR imaging session. The process of transporting the animal between instruments introduced additional errors of ∼0.2 mm. In serial animal imaging studies, the positioning reproducibility within ∼0.8 mm could be obtained.

  12. Chronobiology of ethanol: animal models.

    Science.gov (United States)

    Rosenwasser, Alan M

    2015-06-01

    Clinical and epidemiological observations have revealed that alcohol abuse and alcoholism are associated with widespread disruptions in sleep and other circadian biological rhythms. As with other psychiatric disorders, animal models have been very useful in efforts to better understand the cause and effect relationships underlying the largely correlative human data. This review summarizes the experimental findings indicating bidirectional interactions between alcohol (ethanol) consumption and the circadian timing system, emphasizing behavioral studies conducted in the author's laboratory. Together with convergent evidence from multiple laboratories, the work summarized here establishes that ethanol intake (or administration) alters fundamental properties of the underlying circadian pacemaker. In turn, circadian disruption induced by either environmental or genetic manipulations can alter voluntary ethanol intake. These reciprocal interactions may create a vicious cycle that contributes to the downward spiral of alcohol and drug addiction. In the future, such studies may lead to the development of chronobiologically based interventions to prevent relapse and effectively mitigate some of the societal burden associated with such disorders. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Synthesis, analysis, purification and biodistribution in an animal model of radiopharmaceutical {sup 177}Lu{sup 3+} -dotatato for diagnostic and therapeutic use in neuroendocrine tumors; Sintese, analise, purificacao e biodistribuicao em modelo animal do radiofarmaco {sup 177}Lu{sup 3+} -dotatato para uso diagnostico e terapeutico em tumores neuroendocrinos

    Energy Technology Data Exchange (ETDEWEB)

    Caldeira Filho, Jose de Souza

    2009-07-01

    The aim of this work was to propose rationalization in the synthesis, analysis and purification of radiopharmaceutical {sup 177} Lu{sup 3+} - DOTATATO for diagnostic and therapeutic use in neuroendocrine tumors, as well as for evaluation g biodistribution of this radiopharmaceutical an animal-mode. The complexation reaction for the synthesis of radiopharmaceutical was carried out in ammonium acetate buffer 0.5 M, p H 7.0, for 30 minutes at 95 deg C. The radiochemical purity was > 95%, according to analysis by chromatography in ITLC-SG, when using the sodium citrate buffer 0,1 M, p H 5.0, as the mobile phase. The molar-limit ratio {sup 177}Lu{sup 3+}:DOTATATO, in ammonium acetate buffer 0.5 M, p H 7.0, for 30 minutes at 95 deg C, was dependent on the specific activity and origin of the radioisotope, this being 1:3.5 (370 MBq : 26{mu}g) for that from the Oak Ridge National Laboratory /USA, and 1:16 (370 MBq: 11.8 {mu}g) for that from Nuclear Analytical and Medical Services/Holland, when considering a decay of five days from the production date of te radioisotopes. This rationalization in the synthesis of radiopharmaceutical {sup 177}Lu{sup 3+} - DOTATATO permits high economy in production costs. Chemical studies on the synthesis of radiopharmaceuticals also placed in evidence the interference of {sup 177}Hf{sup 4+}, the decay product of {sup 177}Lu{sup 3=}, as the {sup 177} Lu{sup 3=} competitor for DOTATATO. Radiopharmaceutical preparation proved to be stable during 24 hours, at an activity rate of 2775 MBq, with the addition of 0.6 mg/mL of gentisic acid and when kept in dry ice. In biodistribution studies on Swiss and Nuce mice, the specificity of radiopharmaceutical for somatostatin positive-receptor tissues, such as the pancreas, stomach, lungs, adrenal glands, kidneys and the cell tumor AR42J was demonstrated. (author)

  14. Comparison of the Intraperitoneal, Retroorbital and per Oral Routes for F 18 FDG Administration as Effective Alternatives to Intravenous Administration in Mouse Tumor Models Using Small Animal PET/CT Studies

    International Nuclear Information System (INIS)

    Kim, Chulhan; Kim, In Hye; Kim, Seo il; Kim, Young Sang; Kang, Se Hun; Moon, Seung Hwan; Kim, Tae Sung; Kim, Seok ki

    2011-01-01

    We compared alternative routes for 18F fluorodeoxyglucose (FDG) administration, such as the retroorbital (RO), intraperitoneal (IP) and per oral (PO) routes, with the intravenous (IV) route in normal tissues and tumors of mice. CRL 1642 (ATCC, Lewis lung carcinoma) cells were inoculated in female BALB/c nu/nu mice 6 to 10 weeks old. When the tumor grew to about 9mm in diameter, positron emission tomography (PET) scans were performed after FDG administration via the RO, IP, PO or IV route. Additional serial PET scans were performed using the RO, IV or IP route alternatively from 5 to 29 days after the tumor cell injection. There was no significant difference in the FDG uptake in normal tissues at 60 min after FDG administration via RO, IP and IV routes. PO administration, however, showed delayed distribution and unwanted high gastrointestinal uptake. Tumoral uptake of FDG showed a similar temporal pattern and increased until 60 min after FDG administration in the RO, IP and IV injection groups. In the PO administration group, tumoral uptake was delayed and reduced. There was no statistical difference among the RO, IP and IV administration groups for additional serial PET scans. RO administration is an effective alternative route to IV administration for mouse FDG PET scans using normal mice and tumor models. In addition, IP administration can be a practical alternative in the late phase, although the initial uptake is lower than those in the IV and RO groups.

  15. Mathematical Modeling of Tumor-Tumor Distant Interactions Supports a Systemic Control of Tumor Growth.

    Science.gov (United States)

    Benzekry, Sebastien; Lamont, Clare; Barbolosi, Dominique; Hlatky, Lynn; Hahnfeldt, Philip

    2017-09-15

    Interactions between different tumors within the same organism have major clinical implications, especially in the context of surgery and metastatic disease. Three main explanatory theories (competition, angiogenesis inhibition, and proliferation inhibition) have been proposed, but precise determinants of the phenomenon remain poorly understood. Here, we formalized these theories into mathematical models and performed biological experiments to test them with empirical data. In syngeneic mice bearing two simultaneously implanted tumors, growth of only one of the tumors was significantly suppressed (61% size reduction at day 15, P < 0.05). The competition model had to be rejected, whereas the angiogenesis inhibition and proliferation inhibition models were able to describe the data. Additional models including a theory based on distant cytotoxic log-kill effects were unable to fit the data. The proliferation inhibition model was identifiable and minimal (four parameters), and its descriptive power was validated against the data, including consistency in predictions of single tumor growth when no secondary tumor was present. This theory may also shed new light on single cancer growth insofar as it offers a biologically translatable picture of how local and global action may combine to control local tumor growth and, in particular, the role of tumor-tumor inhibition. This model offers a depiction of concomitant resistance that provides an improved theoretical basis for tumor growth control and may also find utility in therapeutic planning to avoid postsurgery metastatic acceleration. Cancer Res; 77(18); 5183-93. ©2017 AACR . ©2017 American Association for Cancer Research.

  16. Brain tumors in children and adolescents and exposure to animals and farm life

    DEFF Research Database (Denmark)

    Christensen, Jeppe Schultz; Mortensen, Laust Hvas; Röösli, Martin

    2012-01-01

    The etiology of brain tumors in children and adolescents is largely unknown, and very few environmental risk factors have been identified. The aim of this study was to examine the relationship between pre- or postnatal animal contacts or farm exposures and the risk of childhood brain tumors (CBTs...

  17. Anti-tumor immunity generated by photodynamic therapy in a metastatic murine tumor model

    Science.gov (United States)

    Castano, Ana P.; Hamblin, Michael R.

    2005-04-01

    Photodynamic therapy (PDT) is a modality for the treatment of cancer involving excitation of photosensitizers with harmless visible light producing reactive oxygen species. The major biological effects of PDT are apoptosis of tumor cells, destruction of the blood supply and activation of the immune system. The objective of this study is to compare in an animal model of metastatic cancer, PDT alone and PDT combined with low-dose cyclophosphamide (CY). Since the tumor we used is highly metastatic, it is necessary to generate anti-tumor immunity using PDT to both cure the primary tumor and prevent death from metastasis. This immunity may be potentiated by low dose CY. In our model we used J774 cells (a Balb/c reticulum cell sarcoma line with the characteristics of macrophages) and the following PDT regimen: benzoporphyrin derivative monoacid ring A (BPD, 2mg/kg injected IV followed after 15 min by 150 J/cm2 of 690-nm light). CY (50 mg/kg i.p.) was injected 48 hours before light delivery. BPD-PDT led to complete regression of the primary tumor in more than half the mice but no permanent cures were obtained. BPD-PDT in combination with CY led to 60% permanent cures. CY alone gave no permanent cures but did provide a survival advantage. To probe permanent immunity cured animals were rechallenged with the same tumor cell line and the tumors were rejected in 71% of mice cured with BPD-PDT plus CY. We conclude that BPD-PDT in combination with CY gives best overall results and that this is attributable to immunological response activation in addition to PDT-mediated destruction of the tumor.

  18. Towards a reliable animal model of migraine

    DEFF Research Database (Denmark)

    Olesen, Jes; Jansen-Olesen, Inger

    2012-01-01

    The pharmaceutical industry shows a decreasing interest in the development of drugs for migraine. One of the reasons for this could be the lack of reliable animal models for studying the effect of acute and prophylactic migraine drugs. The infusion of glyceryl trinitrate (GTN) is the best validated...... and most studied human migraine model. Several attempts have been made to transfer this model to animals. The different variants of this model are discussed as well as other recent models....

  19. Anesthesia condition for {sup 18}F-FDG imaging of lung metastasis tumors using small animal PET

    Energy Technology Data Exchange (ETDEWEB)

    Woo, Sang-Keun; Lee, Tae Sup; Kim, Kyeong Min; Kim, June-Youp; Jung, Jae Ho; Kang, Joo Hyun [Division of Nuclear Medicine and RI Application, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of); Cheon, Gi Jeong [Division of Nuclear Medicine and RI Application, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of); Department of Nuclear Medicine, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of)], E-mail: larry@kcch.re.kr; Choi, Chang Woon; Lim, Sang Moo [Division of Nuclear Medicine and RI Application, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of); Department of Nuclear Medicine, Korea Institute of Radiological and Medical Sciences (KIRAMS), Nowon-Gu, Seoul 139-706 (Korea, Republic of)

    2008-01-15

    Small animal positron emission tomography (PET) with {sup 18}F-FDG has been increasingly used for tumor imaging in the murine model. The aim of this study was to establish the anesthesia condition for imaging of lung metastasis tumor using small animal {sup 18}F-FDG PET. Methods: To determine the impact of anesthesia on {sup 18}F-FDG distribution in normal mice, five groups were studied under the following conditions: no anesthesia, ketamine and xylazine (Ke/Xy), 0.5% isoflurane (Iso 0.5), 1% isoflurane (Iso 1) and 2% isoflurane (Iso 2). The ex vivo counting, standard uptake value (SUV) image and glucose SUV of {sup 18}F-FDG in various tissues were evaluated. The {sup 18}F-FDG images in the lung metastasis tumor model were obtained under no anesthesia, Ke/Xy and Iso 0.5, and registered with CT image to clarify the tumor region. Results: Blood glucose concentration and muscle uptake of {sup 18}F-FDG in the Ke/Xy group markedly increased more than in the other groups. The Iso 2 group increased {sup 18}F-FDG uptake in heart compared with the other groups. The Iso 0.5 anesthesized group showed the lowest {sup 18}F-FDG uptake in heart and chest wall. The small size of lung metastasis tumor (2 mm) was clearly visualized by {sup 18}F-FDG image with the Iso 0.5 anesthesia. Conclusion: Small animal {sup 18}F-FDG PET imaging with Iso 0.5 anesthesia was appropriate for the detection of lung metastasis tumor. To acquire {sup 18}F-FDG PET images with small animal PET, the type and level of anesthetic should be carefully considered to be suitable for the visualization of target tissue in the experimental model.

  20. Animal models in fetal medicine and obstetrics

    DEFF Research Database (Denmark)

    Dahl Andersen, Maria; Alstrup, Aage Kristian Olsen; Duvald, Christina Søndergaard

    2017-01-01

    Animal models remain essential to understand the fundamental mechanisms occurring in fetal medicine and obstetric diseases, such as intrauterine growth restriction, preeclampsia and gestational diabetes. These vary regarding the employed method used for induction of the disease, and vary regarding...... the animal characteristics (size, number of fetuses, placenta barrier type, etc). While none of these exactly mirrors the human condition, different pregnant animal models (mice, rats, guinea pigs, chinchillas, rabbits, sheep and pigs) are here described with respect to advantages and limitations...

  1. Animal models of cerebral arterial gas embolism

    NARCIS (Netherlands)

    Weenink, Robert P.; Hollmann, Markus W.; van Hulst, Robert A.

    2012-01-01

    Cerebral arterial gas embolism is a dreaded complication of diving and invasive medical procedures. Many different animal models have been used in research on cerebral arterial gas embolism. This review provides an overview of the most important characteristics of these animal models. The properties

  2. Animal models of gastrointestinal and liver diseases. Animal models of acute and chronic pancreatitis.

    Science.gov (United States)

    Zhan, Xianbao; Wang, Fan; Bi, Yan; Ji, Baoan

    2016-09-01

    Animal models of pancreatitis are useful for elucidating the pathogenesis of pancreatitis and developing and testing novel interventions. In this review, we aim to summarize the most commonly used animal models, overview their pathophysiology, and discuss their strengths and limitations. We will also briefly describe common animal study procedures and refer readers to more detailed protocols in the literature. Although animal models include pigs, dogs, opossums, and other animals, we will mainly focus on rodent models because of their popularity. Autoimmune pancreatitis and genetically engineered animal models will be reviewed elsewhere. Copyright © 2016 the American Physiological Society.

  3. Animal models of gastrointestinal and liver diseases. Animal models of acute and chronic pancreatitis

    Science.gov (United States)

    Zhan, Xianbao; Wang, Fan; Bi, Yan

    2016-01-01

    Animal models of pancreatitis are useful for elucidating the pathogenesis of pancreatitis and developing and testing novel interventions. In this review, we aim to summarize the most commonly used animal models, overview their pathophysiology, and discuss their strengths and limitations. We will also briefly describe common animal study procedures and refer readers to more detailed protocols in the literature. Although animal models include pigs, dogs, opossums, and other animals, we will mainly focus on rodent models because of their popularity. Autoimmune pancreatitis and genetically engineered animal models will be reviewed elsewhere. PMID:27418683

  4. Animal model and neurobiology of suicide.

    Science.gov (United States)

    Preti, Antonio

    2011-06-01

    Animal models are formidable tools to investigate the etiology, the course and the potential treatment of an illness. No convincing animal model of suicide has been produced to date, and despite the intensive study of thousands of animal species naturalists have not identified suicide in nonhuman species in field situations. When modeling suicidal behavior in the animal, the greatest challenge is reproducing the role of will and intention in suicide mechanics. To overcome this limitation, current investigations on animals focus on every single step leading to suicide in humans. The most promising endophenotypes worth investigating in animals are the cortisol social-stress response and the aggression/impulsivity trait, involving the serotonergic system. Astroglia, neurotrophic factors and neurotrophins are implied in suicide, too. The prevention of suicide rests on the identification and treatment of every element increasing the risk. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Animal Migraine Models for Drug Development

    DEFF Research Database (Denmark)

    Jansen-Olesen, Inger; Tfelt-Hansen, Peer; Olesen, Jes

    2013-01-01

    responses are likely to be behavioral, allowing multiple experiments in each individual animal. Distinction is made between acute and prophylactic models and how to validate each of them. Modern insight into neurobiological mechanisms of migraine is so good that it is only a question of resources...... for headache has almost come to a standstill partly because of a lack of valid animal models. Here we review previous models with emphasis on optimal characteristics of a future model. In addition to selection of animal species, the method of induction of migraine-like changes and the method of recording...

  6. Overview of Animal Models of Obesity

    Science.gov (United States)

    Lutz, Thomas A.; Woods, Stephen C.

    2012-01-01

    This is a review of animal models of obesity currently used in research. We have focused upon more commonly utilized models since there are far too many newly created models to consider, especially those caused by selective molecular genetic approaches modifying one or more genes in specific populations of cells. Further, we will not discuss the generation and use of inducible transgenic animals (induced knock-out or knock-in) even though they often bear significant advantages compared to traditional transgenic animals; influences of the genetic modification during the development of the animals can be minimized. The number of these animal models is simply too large to be covered in this chapter. PMID:22948848

  7. Animal models of obesity and diabetes mellitus

    DEFF Research Database (Denmark)

    Kleinert, Maximilian; Clemmensen, Christoffer; Hofmann, Susanna M

    2018-01-01

    More than one-third of the worldwide population is overweight or obese and therefore at risk of developing type 2 diabetes mellitus. In order to mitigate this pandemic, safer and more potent therapeutics are urgently required. This necessitates the continued use of animal models to discover...... available animal models of obesity and diabetes and highlight the advantages, limitations and important caveats of each of these models....

  8. Treatment of bovine cancer-eye (and other animal tumors) with heat

    International Nuclear Information System (INIS)

    Doss, J.D.

    1980-01-01

    Hyperthermia appears to be an excellent technique for the treatment of a variety of animal tumors. While this report has emphasized the application of hyperthermia to bovine cancer-eye, there cannot be serious doubt about the potential for wider applications of the technique. We have collaborated with the Animal Resource Facility at the University of New Mexico in the successful treatment of a variety of tumors in small animals which would not be a particular interest to stockmen, but the program included the successful treatment of a number of sarcoids in horses. This investigation involving heat effects on sarcoids will continue, but early results appear to be promising. Other veterinarians are using the commercial hyperthermia instruments to treat a variety of small-animal tumors; these practitioners are enthusiastic about the results but no data have been published to date. We have treated an equine lid tumor with good results, and others are pursuing investigations in this area. Use of commercial hyperthermia instruments for treatment of any condition other than bovine cancer-eye or similar small tumors on animals cannot be justified. Like other therapeutic techniques, hyperthermia must be applied to appropriate cases and retreatment will be necessary in some instances

  9. Animal Models of Middle Ear Cholesteatoma

    Directory of Open Access Journals (Sweden)

    Tomomi Yamamoto-Fukuda

    2011-01-01

    Full Text Available Middle ear acquired cholesteatoma is a pathological condition associated with otitis media, which may be associated with temporal bone resorption, otorrhea and hearing loss, and occasionally various other complications. Cholesteatoma is characterized by the enhanced proliferation of epithelial cells with aberrant morphologic characteristics. Unfortunately, our understanding of the mechanism underlying its pathogenesis is limited. To investigate its pathogenesis, different animal models have been used. This paper provides a brief overview of the current status of research in the field of pathogenesis of middle ear acquired cholesteatoma, four types of animal models previously reported on, up-to-date cholesteatoma research using these animal models, our current studies of the local hybrid ear model, and the future prospect of new animal models of middle ear cholesteatoma.

  10. A large animal model for boron neutron capture therapy

    International Nuclear Information System (INIS)

    Gavin, P.R.; Kraft, S.L.; DeHaan, C.E.; Moore, M.P.; Griebenow, M.L.

    1992-01-01

    An epithermal neutron beam is needed to treat relatively deep seated tumors. The scattering characteristics of neutrons in this energy range dictate that in vivo experiments be conducted in a large animal to prevent unacceptable total body irradiation. The canine species has proven an excellent model to evaluate the various problems of boron neutron capture utilizing an epithermal neutron beam. This paper discusses three major components of the authors study: (1) the pharmacokinetics of borocaptate sodium (NA 2 B 12 H 11 SH or BSH) in dogs with spontaneously occurring brain tumors, (2) the radiation tolerance of normal tissues in the dog using an epithermal beam alone and in combination with borocaptate sodium, and (3) initial treatment of dogs with spontaneously occurring brain tumors utilizing borocaptate sodium and an epithermal neutron beam

  11. Animal models: an important tool in mycology.

    Science.gov (United States)

    Capilla, Javier; Clemons, Karl V; Stevens, David A

    2007-12-01

    Animal models of fungal infections are, and will remain, a key tool in the advancement of the medical mycology. Many different types of animal models of fungal infection have been developed, with murine models the most frequently used, for studies of pathogenesis, virulence, immunology, diagnosis, and therapy. The ability to control numerous variables in performing the model allows us to mimic human disease states and quantitatively monitor the course of the disease. However, no single model can answer all questions and different animal species or different routes of infection can show somewhat different results. Thus, the choice of which animal model to use must be made carefully, addressing issues of the type of human disease to mimic, the parameters to follow and collection of the appropriate data to answer those questions being asked. This review addresses a variety of uses for animal models in medical mycology. It focuses on the most clinically important diseases affecting humans and cites various examples of the different types of studies that have been performed. Overall, animal models of fungal infection will continue to be valuable tools in addressing questions concerning fungal infections and contribute to our deeper understanding of how these infections occur, progress and can be controlled and eliminated.

  12. The development of expertise: animal models?

    Science.gov (United States)

    Helton, William S

    2004-01-01

    There is a continuing debate in the psychological literature between researchers who lean more toward learning theories of expertise development and those who lean more toward talent theories. However, the development of human expertise has not been open to direct experimental methods and will probably continue to elude experimentalists in the future. A promising alternative to direct experimental methods is to use human animal models, a possibility that researchers in expertise seem to have overlooked. However, there are studies in the animal behavior literature that address the development of nonhuman animal expertise without specifically referring to the topic as expertise. In the present study, the author discusses two nonhuman animal examples of expertise development that have been researched by ethologists. Nonhuman animal expertise development, unlike human expertise development, is subject to direct experimentation. The author thus recommends that researchers use nonhuman animals in their studies of expertise.

  13. Potential for tumor therapy with tritiated tetracycline. Summary evaluation. [Animal tests

    Energy Technology Data Exchange (ETDEWEB)

    Davis, R.C.; Wood, P.; Wood, L.L.; Mendelsohn, M.L.

    1976-10-26

    Reports of tetracycline accumulation in human and animal tumors have led a number of investigators to postulate that this drug, if radio-labeled, might have potential as a therapeutic or diagnostic agent. This paper describes attempts to investigate this potential for tritiated tetracycling. The therapeutic studies demonstrated that while a significant reduction in the growth rates of transplanted tumors could be obtained by the administration of heavy doses of TTC relative to uninjected controls, similar reductions were observed in the growth rates of tumors in animals receiving unlabeled TC. In the localization studies in rodents, the concentrations of TTC in normal tissues and tumors were compared and were correlated with the corresponding concentrations of /sup 14/C-thymidine, a measure of proliferative activity.

  14. Animal Models of Chemotherapy-induced Mucositis

    DEFF Research Database (Denmark)

    Sangild, Per T; Shen, René Liang; Pontoppidan, Peter Erik Lotko

    2018-01-01

    of CIM, and how to prevent it. Animal models allow highly controlled experimental conditions, detailed organ (e.g. GIT) insights, standardized, clinically-relevant treatment regimens and discovery of new biomarkers. Still, surprisingly few results from animal models have been translated into clinical CIM......Chemotherapy for cancer patients induces damaging tissue reactions along the epithelium of the gastrointestinal tract (GIT). This chemotherapy-induced mucositis (CIM) is a serious side effect of cytotoxic drugs and several animal models of CIM have been developed to help understand the progression...... mangement and treatments. The results obtained from specific animal models can be difficult to translate to the diverse range of CIM manifestations in patients that vary according to the antineoplastic drugs, dose, underlying (cancer) disease and patient characteristics (e.g. age, genetics, body...

  15. Lessons from animal models of osteoarthritis.

    NARCIS (Netherlands)

    Berg, W.B. van den

    2008-01-01

    Animal models of osteoarthritis (OA) provide valuable insight into pathogenetic pathways. Although OA is not an inflammatory disease, synovial activation clearly plays a role. Matrix metalloproteinases 3 (stromelysin) and 13 (collagenase) appear crucial, and a disintegrin and metalloproteinase with

  16. STRESS RESPONSE STUDIES USING ANIMAL MODELS

    Science.gov (United States)

    This presentation will provide the evidence that ozone exposure in animal models induce neuroendocrine stress response and this stress response modulates lung injury and inflammation through adrenergic and glucocorticoid receptors.

  17. Animal models of cerebral amyloid angiopathy.

    Science.gov (United States)

    Jäkel, Lieke; Van Nostrand, William E; Nicoll, James A R; Werring, David J; Verbeek, Marcel M

    2017-10-15

    Cerebral amyloid angiopathy (CAA), due to vascular amyloid β (Aβ) deposition, is a risk factor for intracerebral haemorrhage and dementia. CAA can occur in sporadic or rare hereditary forms, and is almost invariably associated with Alzheimer's disease (AD). Experimental (animal) models are of great interest in studying mechanisms and potential treatments for CAA. Naturally occurring animal models of CAA exist, including cats, dogs and non-human primates, which can be used for longitudinal studies. However, due to ethical considerations and low throughput of these models, other animal models are more favourable for research. In the past two decades, a variety of transgenic mouse models expressing the human Aβ precursor protein (APP) has been developed. Many of these mouse models develop CAA in addition to senile plaques, whereas some of these models were generated specifically to study CAA. In addition, other animal models make use of a second stimulus, such as hypoperfusion or hyperhomocysteinemia (HHcy), to accelerate CAA. In this manuscript, we provide a comprehensive review of existing animal models for CAA, which can aid in understanding the pathophysiology of CAA and explore the response to potential therapies. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  18. A cognitive model's view of animal cognition

    Directory of Open Access Journals (Sweden)

    Sidney D'MELLO, Stan FRANKLIN

    2011-08-01

    Full Text Available Although it is a relatively new field of study, the animal cognition literature is quite extensive and difficult to synthesize. This paper explores the contributions a comprehensive, computational, cognitive model can make toward organizing and assimilating this literature, as well as toward identifying important concepts and their interrelations. Using the LIDA model as an example, a framework is described within which to integrate the diverse research in animal cognition. Such a framework can provide both an ontology of concepts and their relations, and a working model of an animal’s cognitive processes that can compliment active empirical research. In addition to helping to account for a broad range of cognitive processes, such a model can help to comparatively assess the cognitive capabilities of different animal species. After deriving an ontology for animal cognition from the LIDA model, we apply it to develop the beginnings of a database that maps the cognitive facilities of a variety of animal species. We conclude by discussing future avenues of research, particularly the use of computational models of animal cognition as valuable tools for hypotheses generation and testing [Current Zoology 57 (4: 499–513, 2011].

  19. Decreased tumor uptake of gallium-67 in animals after whole-body irradiation. [Gamma radiation, rats

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, W.P.; Alderson, P.O.; Eckelman, W.C.; Hamilton, R.G.; Weiss, J.F.

    1978-02-01

    The mechanism of decreased Ga-67 citrate retention and serum binding after whole-body irradiation is unknown. To investigate this mechanism and to determine the effects of prior irradiation on tumor uptake of Ga-67, Sprague-Dawley rats bearing a subcutaneous Walker-256 carcinosarcoma were exposed to whole-body Co-60 irradiations of 250-1000 rads. Each animal received 10 ..mu..Ci of Ga-67 citrate intravenously 24 hr after exposure. Control animals received Ga-67 but were not irradiated. Animals were killed at 48 hr and the uptakes (percentage ID/g) in the tumor and other tissues were determined. A blood sample was also obtained to determine the serum iron, unsaturated iron-binding capacity (UIBC) and transferrin level. Tumor uptake and serum UIBC were decreased in irradiated animals, whereas serum iron levels and Ga-67 urinary excretion were increased. There was a significant correlation between the UIBC and the Ga-67 tumor uptake (r = 0.78, p < 0.001, n = 49). Transferrin levels in the irradiated group were not different from control values. The results indicate that the decreased Ga-67 retention and tumor uptake seen after whole-body irradiation are related--at least in part--to the saturation of transferrin by increased levels of circulating iron.

  20. Animal models in motion sickness research

    Science.gov (United States)

    Daunton, Nancy G.

    1990-01-01

    Practical information on candidate animal models for motion sickness research and on methods used to elicit and detect motion sickness in these models is provided. Four good potential models for use in motion sickness experiments include the dog, cat, squirrel monkey, and rat. It is concluded that the appropriate use of the animal models, combined with exploitation of state-of-the-art biomedical techniques, should generate a great step forward in the understanding of motion sickness mechanisms and in the development of efficient and effective approaches to its prevention and treatment in humans.

  1. Radiation-induced relief of pain in an animal model with bone invasion from cancer

    International Nuclear Information System (INIS)

    Seong, J.; Kim, J.; Kim, K.H.; Kim, U.J.; Lee, B.W.

    2003-01-01

    In clinic, local radiation is effective for relief of pain from cancer invasion into the bones. This effect is usually observed before the regression of tumor occurs, which implies radiation-induced pain relief by mechanisms other than tumor irradication. In this study, possible mechanisms were explored in animal model system. To establish an animal model, syngeneic hepatocarcinoma, HCa-I was transplanted on femoral periosteum of C3H/HeJ male mice and bone-invasive tumor growth was identified through the histological analysis. Development of tumor-induced pain was assessed by von Frey filament test, acetone test, and radiant heat test. Animals were also irradiated for their tumors. Any change in pain was analyzed by above tests for the quantitative change and by immunohistochemical stain for the expression of molecules such as c-fos, substance P, and calcitonin gene-related peptide (CGRP) in lumbar spinal cord. Cancer invasion into the bone was started from 7th day after transplantation and became evident at day 14. Objective increase of pain in the ipsilateral thigh was observed at day 14 on von Frey filament test and acetone test, while there was no remarkable regression of the tumors. In this model system, local radiation of tumor resulted in decrease in objective pain on von Frey filament test and acetone test. In the immunohistochemical stain for lumbar spinal cord, the expression of substance P and CGRP but not c-fos increased in tumor-bearing animal compared to the control. The expression of these molecules decreased in animals given local radiation. In summary, an animal model system was established for objective pain from cancer invasion into the bones. Local radiation of tumor induced objective pain relief and this effect seems to be mediated not by tumor regression but through altered production of pain-related molecules

  2. Final model of multicriterionevaluation of animal welfare

    DEFF Research Database (Denmark)

    Bonde, Marianne; Botreau, R; Bracke, MBM

    One major objective of Welfare Quality® is to propose harmonized methods for the overall assessment of animal welfare on farm and at slaughter that are science based and meet societal concerns. Welfare is a multidimensional concept and its assessment requires measures of different aspects. Welfare...... Quality® proposes a formal evaluation model whereby the data on animals or their environment are transformed into value scores that reflect compliance with 12 subcriteria and 4 criteria of good welfare. Each animal unit is then allocated to one of four categories: excellent welfare, enhanced welfare......, acceptable welfare and not classified. This evaluation model is tuned according to the views of experts from animal and social sciences, and stakeholders....

  3. Optogenetics in animal model of alcohol addiction

    Science.gov (United States)

    Nalberczak, Maria; Radwanska, Kasia

    2014-11-01

    Our understanding of the neuronal and molecular basis of alcohol addiction is still not satisfactory. As a consequence we still miss successful therapy of alcoholism. One of the reasons for such state is the lack of appropriate animal models which would allow in-depth analysis of biological basis of addiction. Here we will present our efforts to create the animal model of alcohol addiction in the automated learning device, the IntelliCage setup. Applying this model to optogenetically modified mice with remotely controlled regulation of selected neuronal populations by light may lead to very precise identification of neuronal circuits involved in coding addiction-related behaviors.

  4. Oxymetazoline ototoxicity in a chinchilla animal model.

    Science.gov (United States)

    Daniel, Sam J; Akinpelu, Olubunmi V; Sahmkow, Sofia; Funnell, W Robert J; Akache, Fadi

    2012-01-01

    To investigate possible ototoxic effects of a one-time application of oxymetazoline drops in a chinchilla animal model with tympanostomy tubes. Study Design. A prospective, controlled animal study. The Research Institute of the Montreal's Children Hospital, McGill University Health Centre. Ventilation tubes were inserted in both ears of 12 animals. One ear was randomly assigned to receive oxymetazoline drops (0.5 mL). The contralateral ear did not receive any drops, serving as a control ear. Distortion product otoacoustic emissions were measured bilaterally for a wide range of frequencies (between 1 and 16 kHz) before and 1 day after the application of oxymetazoline in the experimental ears. Two months later, the animals were sacrificed and all cochleae were dissected out and processed for scanning electron microscopy. In this established chinchilla animal model, the measured distortion product otoacoustic emission amplitudes and the morphological appearance on scanning electron microscopy were similar for both control and experimental ears. Oxymetazoline did not cause ototoxicity in a chinchilla animal model 2 months after a single application via a tympanostomy tube.

  5. Animal models of preeclampsia; uses and limitations.

    LENUS (Irish Health Repository)

    McCarthy, F P

    2012-01-31

    Preeclampsia remains a leading cause of maternal and fetal morbidity and mortality and has an unknown etiology. The limited progress made regarding new treatments to reduce the incidence and severity of preeclampsia has been attributed to the difficulties faced in the development of suitable animal models for the mechanistic research of this disease. In addition, animal models need hypotheses on which to be based and the slow development of testable hypotheses has also contributed to this poor progress. The past decade has seen significant advances in our understanding of preeclampsia and the development of viable reproducible animal models has contributed significantly to these advances. Although many of these models have features of preeclampsia, they are still poor overall models of the human disease and limited due to lack of reproducibility and because they do not include the complete spectrum of pathophysiological changes associated with preeclampsia. This review aims to provide a succinct and comprehensive assessment of current animal models of preeclampsia, their uses and limitations with particular attention paid to the best validated and most comprehensive models, in addition to those models which have been utilized to investigate potential therapeutic interventions for the treatment or prevention of preeclampsia.

  6. Animal models for HIV cure research

    Directory of Open Access Journals (Sweden)

    Ben Bruno Policicchio

    2016-01-01

    Full Text Available The HIV-1/AIDS pandemic continues to spread unabated worldwide and no vaccine exists within our grasp. Effective antiretroviral therapy (ART has been developed, but ART cannot clear the virus from the infected patient. A cure for HIV-1 is badly needed to stop both the spread of the virus in human populations and disease progression in infected individuals. A safe and effective cure strategy for HIV infection will require multiple tools and appropriate animal models are tools that are central to cure research. An ideal animal model should recapitulate the essential aspects of HIV pathogenesis and associated immune responses, while permitting invasive studies, thus allowing a thorough evaluation of strategies aimed at reducing the size of the reservoir (functional cure or eliminating the reservoir altogether (sterilizing cure. Since there is no perfect animal model for cure research, multiple models have been tailored and tested to address specific quintessential questions of virus persistence and eradication. The development of new nonhuman primate and mouse models, along with a certain interest in the feline model, have the potential to fuel cure research. In this review, we highlight the major animal models currently utilized for cure research and the contributions of each model to this goal.

  7. Animal Models for HIV Cure Research.

    Science.gov (United States)

    Policicchio, Benjamin B; Pandrea, Ivona; Apetrei, Cristian

    2016-01-01

    The HIV-1/AIDS pandemic continues to spread unabated worldwide, and no vaccine exists within our grasp. Effective antiretroviral therapy (ART) has been developed, but ART cannot clear the virus from the infected patient. A cure for HIV-1 is badly needed to stop both the spread of the virus in human populations and disease progression in infected individuals. A safe and effective cure strategy for human immunodeficiency virus (HIV) infection will require multiple tools, and appropriate animal models are tools that are central to cure research. An ideal animal model should recapitulate the essential aspects of HIV pathogenesis and associated immune responses, while permitting invasive studies, thus allowing a thorough evaluation of strategies aimed at reducing the size of the reservoir (functional cure) or eliminating the reservoir altogether (sterilizing cure). Since there is no perfect animal model for cure research, multiple models have been tailored and tested to address specific quintessential questions of virus persistence and eradication. The development of new non-human primate and mouse models, along with a certain interest in the feline model, has the potential to fuel cure research. In this review, we highlight the major animal models currently utilized for cure research and the contributions of each model to this goal.

  8. Large animal models for stem cell therapy.

    Science.gov (United States)

    Harding, John; Roberts, R Michael; Mirochnitchenko, Oleg

    2013-03-28

    The field of regenerative medicine is approaching translation to clinical practice, and significant safety concerns and knowledge gaps have become clear as clinical practitioners are considering the potential risks and benefits of cell-based therapy. It is necessary to understand the full spectrum of stem cell actions and preclinical evidence for safety and therapeutic efficacy. The role of animal models for gaining this information has increased substantially. There is an urgent need for novel animal models to expand the range of current studies, most of which have been conducted in rodents. Extant models are providing important information but have limitations for a variety of disease categories and can have different size and physiology relative to humans. These differences can preclude the ability to reproduce the results of animal-based preclinical studies in human trials. Larger animal species, such as rabbits, dogs, pigs, sheep, goats, and non-human primates, are better predictors of responses in humans than are rodents, but in each case it will be necessary to choose the best model for a specific application. There is a wide spectrum of potential stem cell-based products that can be used for regenerative medicine, including embryonic and induced pluripotent stem cells, somatic stem cells, and differentiated cellular progeny. The state of knowledge and availability of these cells from large animals vary among species. In most cases, significant effort is required for establishing and characterizing cell lines, comparing behavior to human analogs, and testing potential applications. Stem cell-based therapies present significant safety challenges, which cannot be addressed by traditional procedures and require the development of new protocols and test systems, for which the rigorous use of larger animal species more closely resembling human behavior will be required. In this article, we discuss the current status and challenges of and several major directions

  9. Tumores em animais de produção: aspectos comparativos Tumors in farm animals: comparative aspects

    Directory of Open Access Journals (Sweden)

    Adriano Tony Ramos

    2008-02-01

    Full Text Available Com o objetivo de realizar um estudo retrospectivo de tumores em animais de produção (bovinos, ovinos, eqüinos e suínos, foi realizada uma revisão nos casos suspeitos de neoplasmas recebidos pelo Laboratório Regional de Diagnóstico da Faculdade de Veterinária da Universidade Federal de Pelotas num período de 24 anos (1978-2002. Os aspectos epidemiológicos dos neoplasmas nessas espécies foram relatados, e uma classificação concisa para padronizar a nomenclatura, seguindo padrões internacionais de classificação histológica de tumores, foi realizada. O estudo baseou-se em um universo de 6.267 materiais. Obtiveram-se 175 casos de tumores distribuídos entre as espécies bovina (98/4407, ovina (9/636, eqüina (65/774 e suína (3/450. Esses tumores foram então avaliados e reclassificados. Os dados referentes foram analisados quanto a sua prevalência por raça, sexo, idade e localização anatômica (origem do tumor. Os tumores com maior casuística foram os linfomas nos bovinos, os carcinomas de células escamosas nos bovinos e ovinos e os sarcóides nos eqüinos.Aiming at a complete study on all neoplastic lesions in farm animals (cattle, sheep, horses and swine, a retrospective review was performed covering a 24 years period (1978-2002 at the Regional Diagnostic Laboratory of the Veterinary School in Pelotas, Southern Brazil. The analysis included the review of epidemiological data and the standardization of classification parameters considering current rules of international classification of tumors. Six thousand two hundred and sixty seven samples were analyzed. The distribution among the species was: 98 in cattle, 9 in sheep, 65 in horses and 3 in pigs, over 175 cases detected. Prevalence studies as for the breed, sex, age and anatomical distribution of the tumors were analyzed. Lymphoma in cattle, squamous cell carcinoma in cattle and sheep, and sarcoids in horses were the tumors with higher incidence.

  10. A novel BLK-induced tumor model

    DEFF Research Database (Denmark)

    Petersen, David Leander; Berthelsen, Jens; Willerslev-Olsen, Andreas

    2017-01-01

    -hematological malignancies including breast, kidney, and lung cancers, suggesting that BLK could be a new potential target for therapy. Here, we studied the oncogenic potential of human BLK. We found that engrafted Ba/F3 cells stably expressing constitutive active human BLK formed tumors in mice, whereas neither Ba/F3 cells...... expressing wild type BLK nor non-transfected Ba/F3 cells did. Inhibition of BLK with the clinical grade and broadly reacting SRC family kinase inhibitor dasatinib inhibited growth of BLK-induced tumors. In conclusion, our study provides evidence that human BLK is a true proto-oncogene capable of inducing...... tumors, and we demonstrate a novel BLK activity-dependent tumor model suitable for studies of BLK-driven lymphomagenesis and screening of novel BLK inhibitors in vivo....

  11. Standardization of A Physiologic Hypoparathyroidism Animal Model.

    Science.gov (United States)

    Jung, Soo Yeon; Kim, Ha Yeong; Park, Hae Sang; Yin, Xiang Yun; Chung, Sung Min; Kim, Han Su

    2016-01-01

    Ideal hypoparathyroidism animal models are a prerequisite to developing new treatment modalities for this disorder. The purpose of this study was to evaluate the feasibility of a model whereby rats were parathyroidectomized (PTX) using a fluorescent-identification method and the ideal calcium content of the diet was determined. Thirty male rats were divided into surgical sham (SHAM, n = 5) and PTX plus 0, 0.5, and 2% calcium diet groups (PTX-FC (n = 5), PTX-NC (n = 10), and PTX-HC (n = 10), respectively). Serum parathyroid hormone levels decreased to non-detectable levels in all PTX groups. All animals in the PTX-FC group died within 4 days after the operation. All animals survived when supplied calcium in the diet. However, serum calcium levels were higher in the PTX-HC than the SHAM group. The PTX-NC group demonstrated the most representative modeling of primary hypothyroidism. Serum calcium levels decreased and phosphorus levels increased, and bone volume was increased. All animals survived without further treatment and did not show nephrotoxicity including calcium deposits. These findings demonstrate that PTX animal models produced by using the fluorescent-identification method, and fed a 0.5% calcium diet, are appropriate for hypoparathyroidism treatment studies.

  12. Standardization of A Physiologic Hypoparathyroidism Animal Model.

    Directory of Open Access Journals (Sweden)

    Soo Yeon Jung

    Full Text Available Ideal hypoparathyroidism animal models are a prerequisite to developing new treatment modalities for this disorder. The purpose of this study was to evaluate the feasibility of a model whereby rats were parathyroidectomized (PTX using a fluorescent-identification method and the ideal calcium content of the diet was determined. Thirty male rats were divided into surgical sham (SHAM, n = 5 and PTX plus 0, 0.5, and 2% calcium diet groups (PTX-FC (n = 5, PTX-NC (n = 10, and PTX-HC (n = 10, respectively. Serum parathyroid hormone levels decreased to non-detectable levels in all PTX groups. All animals in the PTX-FC group died within 4 days after the operation. All animals survived when supplied calcium in the diet. However, serum calcium levels were higher in the PTX-HC than the SHAM group. The PTX-NC group demonstrated the most representative modeling of primary hypothyroidism. Serum calcium levels decreased and phosphorus levels increased, and bone volume was increased. All animals survived without further treatment and did not show nephrotoxicity including calcium deposits. These findings demonstrate that PTX animal models produced by using the fluorescent-identification method, and fed a 0.5% calcium diet, are appropriate for hypoparathyroidism treatment studies.

  13. Development of animal models of otitis media.

    Science.gov (United States)

    Park, Moo Kyun; Lee, Byung Don

    2013-04-01

    Otitis media is defined as inflammation of the middle ear, including the auditory ossicles and the Eustachian tube. Otitis media is a major health problem in many societies. The causes of otitis media includes infection and anatomic/physiologic, host, and environmental factors. In general, otitis media is a childhood disease, and anatomic and physiologic changes have great effects on its development. Thus, in vitro or human experimental studies of otitis media are difficult. Several experimental animal models have been introduced to investigate the pathogenesis and treatment of otitis media. However, none are ideal. The aim of this review is to provide a brief overview of the current status of animal models of otitis media with effusion, acute otitis media, and cholesteatoma. This review will assist determination of the most appropriate animal models of otitis media.

  14. Animal models for Gaucher disease research

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    Tamar Farfel-Becker

    2011-11-01

    Full Text Available Gaucher disease (GD, the most common lysosomal storage disorder (LSD, is caused by the defective activity of the lysosomal hydrolase glucocerebrosidase, which is encoded by the GBA gene. Generation of animal models that faithfully recapitulate the three clinical subtypes of GD has proved to be more of a challenge than first anticipated. The first mouse to be produced died within hours after birth owing to skin permeability problems, and mice with point mutations in Gba did not display symptoms correlating with human disease and also died soon after birth. Recently, conditional knockout mice that mimic some features of the human disease have become available. Here, we review the contribution of all currently available animal models to examining pathological pathways underlying GD and to testing the efficacy of new treatment modalities, and propose a number of criteria for the generation of more appropriate animal models of GD.

  15. Model of vascular desmoplastic multispecies tumor growth.

    Science.gov (United States)

    Ng, Chin F; Frieboes, Hermann B

    2017-10-07

    We present a three-dimensional nonlinear tumor growth model composed of heterogeneous cell types in a multicomponent-multispecies system, including viable, dead, healthy host, and extra-cellular matrix (ECM) tissue species. The model includes the capability for abnormal ECM dynamics noted in tumor development, as exemplified by pancreatic ductal adenocarcinoma, including dense desmoplasia typically characterized by a significant increase of interstitial connective tissue. An elastic energy is implemented to provide elasticity to the connective tissue. Cancer-associated fibroblasts (myofibroblasts) are modeled as key contributors to this ECM remodeling. The tumor growth is driven by growth factors released by these stromal cells as well as by oxygen and glucose provided by blood vasculature which along with lymphatics are stimulated to proliferate in and around the tumor based on pro-angiogenic factors released by hypoxic tissue regions. Cellular metabolic processes are simulated, including respiration and glycolysis with lactate fermentation. The bicarbonate buffering system is included for cellular pH regulation. This model system may be of use to simulate the complex interactions between tumor and stromal cells as well as the associated ECM and vascular remodeling that typically characterize malignant cancers notorious for poor therapeutic response. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Augmented reality in a tumor resection model.

    Science.gov (United States)

    Chauvet, Pauline; Collins, Toby; Debize, Clement; Novais-Gameiro, Lorraine; Pereira, Bruno; Bartoli, Adrien; Canis, Michel; Bourdel, Nicolas

    2018-03-01

    Augmented Reality (AR) guidance is a technology that allows a surgeon to see sub-surface structures, by overlaying pre-operative imaging data on a live laparoscopic video. Our objectives were to evaluate a state-of-the-art AR guidance system in a tumor surgical resection model, comparing the accuracy of the resection with and without the system. Our system has three phases. Phase 1: using the MRI images, the kidney's and pseudotumor's surfaces are segmented to construct a 3D model. Phase 2: the intra-operative 3D model of the kidney is computed. Phase 3: the pre-operative and intra-operative models are registered, and the laparoscopic view is augmented with the pre-operative data. We performed a prospective experimental study on ex vivo porcine kidneys. Alginate was injected into the parenchyma to create pseudotumors measuring 4-10 mm. The kidneys were then analyzed by MRI. Next, the kidneys were placed into pelvictrainers, and the pseudotumors were laparoscopically resected. The AR guidance system allows the surgeon to see tumors and margins using classical laparoscopic instruments, and a classical screen. The resection margins were measured microscopically to evaluate the accuracy of resection. Ninety tumors were segmented: 28 were used to optimize the AR software, and 62 were used to randomly compare surgical resection: 29 tumors were resected using AR and 33 without AR. The analysis of our pathological results showed 4 failures (tumor with positive margins) (13.8%) in the AR group, and 10 (30.3%) in the Non-AR group. There was no complete miss in the AR group, while there were 4 complete misses in the non-AR group. In total, 14 (42.4%) tumors were completely missed or had a positive margin in the non-AR group. Our AR system enhances the accuracy of surgical resection, particularly for small tumors. Crucial information such as resection margins and vascularization could also be displayed.

  17. Development of a New Positron Emission Tomography Tracer for Targeting Tumor Angiogenesis: Synthesis, Small Animal Imaging, and Radiation Dosimetry

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    David S. Lalush

    2013-05-01

    Full Text Available Angiogenesis plays a key role in cancer progression and correlates with disease aggressiveness and poor clinical outcomes. Affinity ligands discovered by screening phage display random peptide libraries can be engineered to molecularly target tumor blood vessels for noninvasive imaging and early detection of tumor aggressiveness. In this study, we tested the ability of a phage-display-selected peptide sequence recognizing specifically bone marrow- derived pro-angiogenic tumor-homing cells, the QFP-peptide, radiolabeled with 64Cu radioisotope to selectively image tumor vasculature in vivo by positron emission tomography (PET. To prepare the targeted PET tracer we modified QFP-phage with the DOTA chelator and radiolabeled the purified QFP-phage-DOTA intermediate with 64Cu to obtain QFP-targeted radioconjugate with high radiopharmaceutical yield and specific activity. We evaluated the new PET tracer in vivo in a subcutaneous (s.c. Lewis lung carcinoma (LLC mouse model and conducted tissue distribution, small animal PET/CT imaging study, autoradiography, histology, fluorescence imaging, and dosimetry assessments. The results from this study show that, in the context of the s.c. LLC immunocompetent mouse model, the QFP-tracer can target tumor blood vessels selectively. However, further optimization of the biodistribution and dosimetry profile of the tracer is necessary to ensure efficient radiopharmaceutical applications enabled by the biological specificity of the QFP-peptide.

  18. Animal models of asthma: utility and limitations

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    Aun MV

    2017-11-01

    Full Text Available Marcelo Vivolo Aun,1,2 Rafael Bonamichi-Santos,1,2 Fernanda Magalhães Arantes-Costa,2 Jorge Kalil,1 Pedro Giavina-Bianchi1 1Clinical Immunology and Allergy Division, Department of Internal Medicine, University of São Paulo School of Medicine, São Paulo, Brazil, 2Laboratory of Experimental Therapeutics (LIM20, Department of Internal Medicine, University of Sao Paulo, Sao Paulo, Brazil Abstract: Clinical studies in asthma are not able to clear up all aspects of disease pathophysiology. Animal models have been developed to better understand these mechanisms and to evaluate both safety and efficacy of therapies before starting clinical trials. Several species of animals have been used in experimental models of asthma, such as Drosophila, rats, guinea pigs, cats, dogs, pigs, primates and equines. However, the most common species studied in the last two decades is mice, particularly BALB/c. Animal models of asthma try to mimic the pathophysiology of human disease. They classically include two phases: sensitization and challenge. Sensitization is traditionally performed by intraperitoneal and subcutaneous routes, but intranasal instillation of allergens has been increasingly used because human asthma is induced by inhalation of allergens. Challenges with allergens are performed through aerosol, intranasal or intratracheal instillation. However, few studies have compared different routes of sensitization and challenge. The causative allergen is another important issue in developing a good animal model. Despite being more traditional and leading to intense inflammation, ovalbumin has been replaced by aeroallergens, such as house dust mites, to use the allergens that cause human disease. Finally, researchers should define outcomes to be evaluated, such as serum-specific antibodies, airway hyperresponsiveness, inflammation and remodeling. The present review analyzes the animal models of asthma, assessing differences between species, allergens and routes

  19. Modeling tumor invasion and metastasis in Drosophila

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    Wayne O. Miles

    2011-11-01

    Full Text Available Conservation of major signaling pathways between humans and flies has made Drosophila a useful model organism for cancer research. Our understanding of the mechanisms regulating cell growth, differentiation and development has been considerably advanced by studies in Drosophila. Several recent high profile studies have examined the processes constraining the metastatic growth of tumor cells in fruit fly models. Cell invasion can be studied in the context of an in vivo setting in flies, enabling the genetic requirements of the microenvironment of tumor cells undergoing metastasis to be analyzed. This Perspective discusses the strengths and limitations of Drosophila models of cancer invasion and the unique tools that have enabled these studies. It also highlights several recent reports that together make a strong case for Drosophila as a system with the potential for both testing novel concepts in tumor progression and cell invasion, and for uncovering players in metastasis.

  20. Are animal models predictive for humans?

    Directory of Open Access Journals (Sweden)

    Greek Ray

    2009-01-01

    Full Text Available Abstract It is one of the central aims of the philosophy of science to elucidate the meanings of scientific terms and also to think critically about their application. The focus of this essay is the scientific term predict and whether there is credible evidence that animal models, especially in toxicology and pathophysiology, can be used to predict human outcomes. Whether animals can be used to predict human response to drugs and other chemicals is apparently a contentious issue. However, when one empirically analyzes animal models using scientific tools they fall far short of being able to predict human responses. This is not surprising considering what we have learned from fields such evolutionary and developmental biology, gene regulation and expression, epigenetics, complexity theory, and comparative genomics.

  1. Use of the vasodilator sodium nitroprusside during local hyperthermia: effects on tumor temperature and tumor response in a rat tumor model

    International Nuclear Information System (INIS)

    Krossnes, Baard Kronen; Mella, Olav; Dahl, Olav

    1996-01-01

    .3 and 0.4 deg. C higher during SNP infusion in the MFF and pentobarbital group, respectively. Conclusion: We have developed a small animal model in inbred rats feasible for exploring the influence of a stable blood pressure reduction induced by SNP, on the effect of HT given alone or in combination with other treatment modalities to a transplantable tumor. The greatly increased cytotoxic effect of local waterbath HT in the present tumor response experiments is probably a consequence of increased tumor temperature during SNP infusion

  2. Henipavirus Infections: Lessons from Animal Models

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    Kévin P. Dhondt

    2013-04-01

    Full Text Available The Henipavirus genus contains two highly lethal viruses, the Hendra and Nipah viruses and one, recently discovered, apparently nonpathogenic member; Cedar virus. These three, negative-sense single-stranded RNA viruses, are hosted by fruit bats and use EphrinB2 receptors for entry into cells. The Hendra and Nipah viruses are zoonotic pathogens that emerged in the middle of 90s and have caused severe, and often fatal, neurologic and/or respiratory diseases in both humans and different animals; including spillover into equine and porcine species. Development of relevant models is critical for a better understanding of viral pathogenesis, generating new diagnostic tools, and assessing anti-viral therapeutics and vaccines. This review summarizes available data on several animal models where natural and/or experimental infection has been demonstrated; including pteroid bats, horses, pigs, cats, hamsters, guinea pigs, ferrets, and nonhuman primates. It recapitulates the principal features of viral pathogenesis in these animals and current knowledge on anti-viral immune responses. Lastly it describes the recently characterized murine animal model, which provides the possibility to use numerous and powerful tools available for mice to further decipher henipaviruses immunopathogenesis, prophylaxis, and treatment. The utility of different models to analyze important aspects of henipaviruses-induced disease in humans, potential routes of transmission, and therapeutic approaches are equally discussed.

  3. The wobbler mouse, an ALS animal model

    DEFF Research Database (Denmark)

    Moser, Jakob Maximilian; Bigini, Paolo; Schmitt-John, Thomas

    2013-01-01

    This review article is focused on the research progress made utilizing the wobbler mouse as animal model for human motor neuron diseases, especially the amyotrophic lateral sclerosis (ALS). The wobbler mouse develops progressive degeneration of upper and lower motor neurons and shows striking...

  4. Animal models of chronic obstructive pulmonary disease.

    Science.gov (United States)

    Pérez-Rial, Sandra; Girón-Martínez, Álvaro; Peces-Barba, Germán

    2015-03-01

    Animal models of disease have always been welcomed by the scientific community because they provide an approach to the investigation of certain aspects of the disease in question. Animal models of COPD cannot reproduce the heterogeneity of the disease and usually only manage to represent the disease in its milder stages. Moreover, airflow obstruction, the variable that determines patient diagnosis, not always taken into account in the models. For this reason, models have focused on the development of emphysema, easily detectable by lung morphometry, and have disregarded other components of the disease, such as airway injury or associated vascular changes. Continuous, long-term exposure to cigarette smoke is considered the main risk factor for this disease, justifying the fact that the cigarette smoke exposure model is the most widely used. Some variations on this basic model, related to exposure time, the association of other inducers or inhibitors, exacerbations or the use of transgenic animals to facilitate the identification of pathogenic pathways have been developed. Some variations or heterogeneity of this disease, then, can be reproduced and models can be designed for resolving researchers' questions on disease identification or treatment responses. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.

  5. Spherical Cancer Models in Tumor Biology

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    Louis-Bastien Weiswald

    2015-01-01

    Full Text Available Three-dimensional (3D in vitro models have been used in cancer research as an intermediate model between in vitro cancer cell line cultures and in vivo tumor. Spherical cancer models represent major 3D in vitro models that have been described over the past 4 decades. These models have gained popularity in cancer stem cell research using tumorospheres. Thus, it is crucial to define and clarify the different spherical cancer models thus far described. Here, we focus on in vitro multicellular spheres used in cancer research. All these spherelike structures are characterized by their well-rounded shape, the presence of cancer cells, and their capacity to be maintained as free-floating cultures. We propose a rational classification of the four most commonly used spherical cancer models in cancer research based on culture methods for obtaining them and on subsequent differences in sphere biology: the multicellular tumor spheroid model, first described in the early 70s and obtained by culture of cancer cell lines under nonadherent conditions; tumorospheres, a model of cancer stem cell expansion established in a serum-free medium supplemented with growth factors; tissue-derived tumor spheres and organotypic multicellular spheroids, obtained by tumor tissue mechanical dissociation and cutting. In addition, we describe their applications to and interest in cancer research; in particular, we describe their contribution to chemoresistance, radioresistance, tumorigenicity, and invasion and migration studies. Although these models share a common 3D conformation, each displays its own intrinsic properties. Therefore, the most relevant spherical cancer model must be carefully selected, as a function of the study aim and cancer type.

  6. Spherical cancer models in tumor biology.

    Science.gov (United States)

    Weiswald, Louis-Bastien; Bellet, Dominique; Dangles-Marie, Virginie

    2015-01-01

    Three-dimensional (3D) in vitro models have been used in cancer research as an intermediate model between in vitro cancer cell line cultures and in vivo tumor. Spherical cancer models represent major 3D in vitro models that have been described over the past 4 decades. These models have gained popularity in cancer stem cell research using tumorospheres. Thus, it is crucial to define and clarify the different spherical cancer models thus far described. Here, we focus on in vitro multicellular spheres used in cancer research. All these spherelike structures are characterized by their well-rounded shape, the presence of cancer cells, and their capacity to be maintained as free-floating cultures. We propose a rational classification of the four most commonly used spherical cancer models in cancer research based on culture methods for obtaining them and on subsequent differences in sphere biology: the multicellular tumor spheroid model, first described in the early 70s and obtained by culture of cancer cell lines under nonadherent conditions; tumorospheres, a model of cancer stem cell expansion established in a serum-free medium supplemented with growth factors; tissue-derived tumor spheres and organotypic multicellular spheroids, obtained by tumor tissue mechanical dissociation and cutting. In addition, we describe their applications to and interest in cancer research; in particular, we describe their contribution to chemoresistance, radioresistance, tumorigenicity, and invasion and migration studies. Although these models share a common 3D conformation, each displays its own intrinsic properties. Therefore, the most relevant spherical cancer model must be carefully selected, as a function of the study aim and cancer type. Copyright © 2014 Neoplasia Press, Inc. Published by Elsevier Inc. All rights reserved.

  7. Large Mammalian Animal Models of Heart Disease

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    Paula Camacho

    2016-10-01

    Full Text Available Due to the biological complexity of the cardiovascular system, the animal model is an urgent pre-clinical need to advance our knowledge of cardiovascular disease and to explore new drugs to repair the damaged heart. Ideally, a model system should be inexpensive, easily manipulated, reproducible, a biological representative of human disease, and ethically sound. Although a larger animal model is more expensive and difficult to manipulate, its genetic, structural, functional, and even disease similarities to humans make it an ideal model to first consider. This review presents the commonly-used large animals—dog, sheep, pig, and non-human primates—while the less-used other large animals—cows, horses—are excluded. The review attempts to introduce unique points for each species regarding its biological property, degrees of susceptibility to develop certain types of heart diseases, and methodology of induced conditions. For example, dogs barely develop myocardial infarction, while dilated cardiomyopathy is developed quite often. Based on the similarities of each species to the human, the model selection may first consider non-human primates—pig, sheep, then dog—but it also depends on other factors, for example, purposes, funding, ethics, and policy. We hope this review can serve as a basic outline of large animal models for cardiovascular researchers and clinicians.

  8. [Skin defect modeling in experimental animals].

    Science.gov (United States)

    Oleshko, A N; Kornienko, V V; Tkachenko, Yu A; Kurganskaya, V A

    2015-02-01

    To assess the skin regeneration and explore new medical devices for the treatment of skin defects is necessary to conduct long-term experiments using laboratory animals. Currently, there are many methods for skin trauma modeling but most of them have disadvantages that limit their use. The purpose of this work - the development of an experimental model of the formation of skin defect of various etiologies with the specified parameters of depth and area of damage to the absence of systemic effects on the animal's body. We have developed an installation that allows us to form a skin defect of mechanical, thermal and chemical etiology with area from 1.76 cm2 to 2.0 cm2. The experiment was conducted on 18 male laboratory rats to examine the effectiveness of current method and control the depth and area of the defect. As a result of the new methodology, we were able to carry out simulation skin injuries of different etiology on laboratory animals in the short term and reduce the severity of injuries to extend the life span of animals to monitor the repair processes, as well as to standardize the modeling of injuries according to the criteria of area and depth of the defect.

  9. Evolution of animal models in cancer vaccine development.

    Science.gov (United States)

    Wei, Wei-Zen; Jones, Richard F; Juhasz, Csaba; Gibson, Heather; Veenstra, Jesse

    2015-12-16

    Advances in cancer vaccine development are facilitated by animal models reflecting key features of human cancer and its interface with host immunity. Several series of transplantable preneoplastic and neoplastic mouse mammary lesions have been used to delineate mechanisms of anti-tumor immunity. Mimicking immune tolerance to tumor-associated antigens (TAA) such as HER2/neu, transgenic mice developing spontaneous mammary tumors are strong model systems for pre-clinical vaccine testing. In these models, HER2 DNA vaccines are easily administered, well-tolerated, and induce both humoral and cellular immunity. Although engineered mouse strains have advanced cancer immunotherapy, basic shortcomings remain. For example, multiple mouse strains have to be tested to recapitulate genetic regulation of immune tolerance in humans. Outbred domestic felines more closely parallel humans in the natural development of HER2 positive breast cancer and their varying genetic background. Electrovaccination with heterologous HER2 DNA induces robust adaptive immune responses in cats. Importantly, homologous feline HER2 DNA with a single amino acid substitution elicits unique antibodies to feline mammary tumor cells, unlocking a new vaccine principle. As an alternative approach to targeted vaccination, non-surgical tumor ablation such as cryoablation induces anti-tumor immunity via in situ immunization, particularly when combined with toll-like receptor (TLR) agonist. As strategies for vaccination advance, non-invasive monitoring of host response becomes imperative. As an example, magnetic resonance imaging (MRI) and positron emission tomography (PET) scanning following administration of tryptophan metabolism tracer [11C]-alpha-methyl-tryptophan (AMT) provides non-invasive imaging of both tumor growth and metabolic activities. Because AMT is a substrate of indoleamine-pyrrole 2,3-dioxygenase (IDO), an enzyme that produces the immune regulatory molecule kynurenine, AMT imaging can provide

  10. Phenotyping animal models of diabetic neuropathy

    DEFF Research Database (Denmark)

    Biessels, G J; Bril, V; Calcutt, N A

    2014-01-01

    of statistically different values between diabetic and control animals in 2 of 3 assessments (nocifensive behavior, nerve conduction velocities, or nerve structure). The participants propose that this framework would allow different research groups to compare and share data, with an emphasis on data targeted......NIDDK, JDRF, and the Diabetic Neuropathy Study Group of EASD sponsored a meeting to explore the current status of animal models of diabetic peripheral neuropathy. The goal of the workshop was to develop a set of consensus criteria for the phenotyping of rodent models of diabetic neuropathy....... The discussion was divided into five areas: (1) status of commonly used rodent models of diabetes, (2) nerve structure, (3) electrophysiological assessments of nerve function, (4) behavioral assessments of nerve function, and (5) the role of biomarkers in disease phenotyping. Participants discussed the current...

  11. Animal models of anxiety disorders and stress

    Directory of Open Access Journals (Sweden)

    Alline C. Campos

    2013-01-01

    Full Text Available Anxiety and stress-related disorders are severe psychiatric conditions that affect performance in daily tasks and represent a high cost to public health. The initial observation of Charles Darwin that animals and human beings share similar characteristics in the expression of emotion raise the possibility of studying the mechanisms of psychiatric disorders in other mammals (mainly rodents. The development of animal models of anxiety and stress has helped to identify the pharmacological mechanisms and potential clinical effects of several drugs. Animal models of anxiety are based on conflict situations that can generate opposite motivational states induced by approach-avoidance situations. The present review revisited the main rodent models of anxiety and stress responses used worldwide. Here we defined as “ethological” the tests that assess unlearned/unpunished responses (such as the elevated plus maze, light-dark box, and open field, whereas models that involve learned/punished responses are referred to as “conditioned operant conflict tests” (such as the Vogel conflict test. We also discussed models that involve mainly classical conditioning tests (fear conditioning. Finally, we addressed the main protocols used to induce stress responses in rodents, including psychosocial (social defeat and neonatal isolation stress, physical (restraint stress, and chronic unpredictable stress.

  12. A Western-type diet accelerates tumor progression in an autochthonous mouse model of prostate cancer.

    Science.gov (United States)

    Llaverias, Gemma; Danilo, Christiane; Wang, Yu; Witkiewicz, Agnes K; Daumer, Kristin; Lisanti, Michael P; Frank, Philippe G

    2010-12-01

    Epidemiological studies have provided evidence suggesting an important role for diet and obesity in the development of cancer. Specifically, lipid nutrients of the diet have been identified as important regulators of tumor development and progression. In the present study, we have examined the role of dietary fat and cholesterol in the initiation and progression of prostate cancer using the well-characterized TRAMP mouse model. Consumption of a Western-type diet--that is, enriched in both fat and cholesterol--accelerated prostate tumor incidence and tumor burden compared to mice fed a control chow diet. Furthermore, we also show that this diet increased the extent and the histological grade of prostate tumors. These findings were confirmed by the presence of increased levels of protein markers of advanced tumors in prostates obtained from animals fed a Western-type diet compared to those obtained from control animals. Increased lung metastases in animals fed a Western-type diet were also observed. In addition, we found that with a Western diet, animals bearing tumors presented with reduced plasma cholesterol levels compared with animals fed a control diet. Finally, we show that tumors obtained from animals fed a Western-type diet displayed increased expression of the high-density lipoprotein receptor SR-BI and increased angiogenesis. Taken together, our data suggest that dietary fat and cholesterol play an important role in the development of prostate cancer.

  13. Fantastic animals as an experimental model to teach animal adaptation

    Science.gov (United States)

    Guidetti, Roberto; Baraldi, Laura; Calzolai, Caterina; Pini, Lorenza; Veronesi, Paola; Pederzoli, Aurora

    2007-01-01

    Background Science curricula and teachers should emphasize evolution in a manner commensurate with its importance as a unifying concept in science. The concept of adaptation represents a first step to understand the results of natural selection. We settled an experimental project of alternative didactic to improve knowledge of organism adaptation. Students were involved and stimulated in learning processes by creative activities. To set adaptation in a historic frame, fossil records as evidence of past life and evolution were considered. Results The experimental project is schematized in nine phases: review of previous knowledge; lesson on fossils; lesson on fantastic animals; planning an imaginary world; creation of an imaginary animal; revision of the imaginary animals; adaptations of real animals; adaptations of fossil animals; and public exposition. A rubric to evaluate the student's performances is reported. The project involved professors and students of the University of Modena and Reggio Emilia and of the "G. Marconi" Secondary School of First Degree (Modena, Italy). Conclusion The educational objectives of the project are in line with the National Indications of the Italian Ministry of Public Instruction: knowledge of the characteristics of living beings, the meanings of the term "adaptation", the meaning of fossils, the definition of ecosystem, and the particularity of the different biomes. At the end of the project, students will be able to grasp particular adaptations of real organisms and to deduce information about the environment in which the organism evolved. This project allows students to review previous knowledge and to form their personalities. PMID:17767729

  14. Spatiotemporal epidemic models for rabies among animals

    Directory of Open Access Journals (Sweden)

    Shigui Ruan

    2017-08-01

    Full Text Available Rabies is a serious concern to public health and wildlife management worldwide. Over the last three decades, various mathematical models have been proposed to study the transmission dynamics of rabies. In this paper we provide a mini-review on some reaction-diffusion models describing the spatial spread of rabies among animals. More specifically, we introduce the susceptible-exposed-infectious models for the spatial transmission of rabies among foxes (Murray et al., 1986, the spatiotemporal epidemic model for rabies among raccoons (Neilan and Lenhart, 2011, the diffusive rabies model for skunk and bat interactions (Bonchering et al., 2012, and the reaction-diffusion model for rabies among dogs (Zhang et al., 2012. Numerical simulations on the spatiotemporal dynamics of these models from these papers are presented.

  15. Antidiabetic dietary materials and animal models.

    Science.gov (United States)

    Wang, Sunan; Zhu, Fan

    2016-07-01

    The ever-increasing occurrence of diabetes worldwide demands cost-effective anti-diabetic strategies. Food-based materials have great potential as efficient anti-diabetic agents. Focusing on the literatures of the recent 5years, this review summarizes the methods, findings, and limitations of each research involving non-medicinal foods (individual and mixed) and diabetic animal models. Various types of fruits, vegetables, legumes, cereals, spices, beverages, oilseeds, and edible oils showed antidiabetic effects in different animal models. Animal feeding trials rarely had identical designs in food doses, feeding schedules, and routes of administration, as well as biochemical markers for antidiabetic evaluation. Various possible cellular and metabolic targets were speculated for the anti-hyperglycemic effects of the dietary materials, and the molecular mechanisms of action remain to be better explored. Short-term (maximum 16weeks) antidiabetic studies have been established. Limited safety/tolerability data are available for antidiabetic dietary materials. Findings from current animal studies present a generic antidiabetic dietary pattern associated with plant-based whole foods, which agrees well with the findings of epidemiological studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Animal Models of Human Placentation - A Review

    DEFF Research Database (Denmark)

    Carter, Anthony Michael

    2007-01-01

    This review examines the strengths and weaknesses of animal models of human placentation and pays particular attention to the mouse and non-human primates. Analogies can be drawn between mouse and human in placental cell types and genes controlling placental development. There are, however...... and delivers poorly developed young. Guinea pig is a good alternative rodent model and among the few species known to develop pregnancy toxaemia. The sheep is well established as a model in fetal physiology but is of limited value for placental research. The ovine placenta is epitheliochorial...

  17. Datamining approaches for modeling tumor control probability.

    Science.gov (United States)

    Naqa, Issam El; Deasy, Joseph O; Mu, Yi; Huang, Ellen; Hope, Andrew J; Lindsay, Patricia E; Apte, Aditya; Alaly, James; Bradley, Jeffrey D

    2010-11-01

    Tumor control probability (TCP) to radiotherapy is determined by complex interactions between tumor biology, tumor microenvironment, radiation dosimetry, and patient-related variables. The complexity of these heterogeneous variable interactions constitutes a challenge for building predictive models for routine clinical practice. We describe a datamining framework that can unravel the higher order relationships among dosimetric dose-volume prognostic variables, interrogate various radiobiological processes, and generalize to unseen data before when applied prospectively. Several datamining approaches are discussed that include dose-volume metrics, equivalent uniform dose, mechanistic Poisson model, and model building methods using statistical regression and machine learning techniques. Institutional datasets of non-small cell lung cancer (NSCLC) patients are used to demonstrate these methods. The performance of the different methods was evaluated using bivariate Spearman rank correlations (rs). Over-fitting was controlled via resampling methods. Using a dataset of 56 patients with primary NCSLC tumors and 23 candidate variables, we estimated GTV volume and V75 to be the best model parameters for predicting TCP using statistical resampling and a logistic model. Using these variables, the support vector machine (SVM) kernel method provided superior performance for TCP prediction with an rs=0.68 on leave-one-out testing compared to logistic regression (rs=0.4), Poisson-based TCP (rs=0.33), and cell kill equivalent uniform dose model (rs=0.17). The prediction of treatment response can be improved by utilizing datamining approaches, which are able to unravel important non-linear complex interactions among model variables and have the capacity to predict on unseen data for prospective clinical applications.

  18. Experimental animal modelling for TB vaccine development

    Directory of Open Access Journals (Sweden)

    Pere-Joan Cardona

    2017-03-01

    Full Text Available Research for a novel vaccine to prevent tuberculosis is an urgent medical need. The current vaccine, BCG, has demonstrated a non-homogenous efficacy in humans, but still is the gold standard to be improved upon. In general, the main indicator for testing the potency of new candidates in animal models is the reduction of the bacillary load in the lungs at the acute phase of the infection. Usually, this reduction is similar to that induced by BCG, although in some cases a weak but significant improvement can be detected, but none of candidates are able to prevent establishment of infection. The main characteristics of several laboratory animals are reviewed, reflecting that none are able to simulate the whole characteristics of human tuberculosis. As, so far, no surrogate of protection has been found, it is important to test new candidates in several models in order to generate convincing evidence of efficacy that might be better than that of BCG in humans. It is also important to investigate the use of “in silico” and “ex vivo” models to better understand experimental data and also to try to replace, or at least reduce and refine experimental models in animals.

  19. Animals living in polluted environments are a potential source of anti-tumor molecule(s).

    Science.gov (United States)

    Jeyamogan, Shareni; Khan, Naveed Ahmed; Siddiqui, Ruqaiyyah

    2017-11-01

    Despite advances in therapeutic interventions and supportive care, the morbidity and mortality associated with cancer have remained significant. Thus, there is a need for newer and more powerful anti-tumor agents. The search for new anti-tumor compounds originating from natural resources is a promising research area. Animals living in polluted environments are a potent source of anti-tumor agents. Under polluted milieus, species such as crocodiles, feed on rotten meat, are exposed to heavy metals, endure high levels of radiation, and are among the very few species to survive the catastrophic Cretaceous-Tertiary extinction event with a prolonged lifespan. Thus, it is reasonable to speculate that animals such as crocodiles have developed mechanisms to defend themselves against cancer. The discovery of antitumor activity in animals such as crocodiles, whales, sharks, etc. will stimulate research in finding therapeutic molecules from unusual sources, and has potential for the development of novel antitumor compound(s) that may also overcome current drug resistance. Nevertheless, intensive research in the next few years will be required to realize these expectations.

  20. A new ODE tumor growth modeling based on tumor population dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Oroji, Amin; Omar, Mohd bin [Institute of Mathematical Sciences, Faculty of Science University of Malaya, 50603 Kuala Lumpur, Malaysia amin.oroji@siswa.um.edu.my, mohd@um.edu.my (Malaysia); Yarahmadian, Shantia [Mathematics Department Mississippi State University, USA Syarahmadian@math.msstate.edu (United States)

    2015-10-22

    In this paper a new mathematical model for the population of tumor growth treated by radiation is proposed. The cells dynamics population in each state and the dynamics of whole tumor population are studied. Furthermore, a new definition of tumor lifespan is presented. Finally, the effects of two main parameters, treatment parameter (q), and repair mechanism parameter (r) on tumor lifespan are probed, and it is showed that the change in treatment parameter (q) highly affects the tumor lifespan.

  1. A new ODE tumor growth modeling based on tumor population dynamics

    International Nuclear Information System (INIS)

    Oroji, Amin; Omar, Mohd bin; Yarahmadian, Shantia

    2015-01-01

    In this paper a new mathematical model for the population of tumor growth treated by radiation is proposed. The cells dynamics population in each state and the dynamics of whole tumor population are studied. Furthermore, a new definition of tumor lifespan is presented. Finally, the effects of two main parameters, treatment parameter (q), and repair mechanism parameter (r) on tumor lifespan are probed, and it is showed that the change in treatment parameter (q) highly affects the tumor lifespan

  2. Modeling measurement error in tumor characterization studies

    Directory of Open Access Journals (Sweden)

    Marjoram Paul

    2011-07-01

    Full Text Available Abstract Background Etiologic studies of cancer increasingly use molecular features such as gene expression, DNA methylation and sequence mutation to subclassify the cancer type. In large population-based studies, the tumor tissues available for study are archival specimens that provide variable amounts of amplifiable DNA for molecular analysis. As molecular features measured from small amounts of tumor DNA are inherently noisy, we propose a novel approach to improve statistical efficiency when comparing groups of samples. We illustrate the phenomenon using the MethyLight technology, applying our proposed analysis to compare MLH1 DNA methylation levels in males and females studied in the Colon Cancer Family Registry. Results We introduce two methods for computing empirical weights to model heteroscedasticity that is caused by sampling variable quantities of DNA for molecular analysis. In a simulation study, we show that using these weights in a linear regression model is more powerful for identifying differentially methylated loci than standard regression analysis. The increase in power depends on the underlying relationship between variation in outcome measure and input DNA quantity in the study samples. Conclusions Tumor characteristics measured from small amounts of tumor DNA are inherently noisy. We propose a statistical analysis that accounts for the measurement error due to sampling variation of the molecular feature and show how it can improve the power to detect differential characteristics between patient groups.

  3. Animal models of age related macular degeneration

    Science.gov (United States)

    Pennesi, Mark E.; Neuringer, Martha; Courtney, Robert J.

    2013-01-01

    Age related macular degeneration (AMD) is the leading cause of vision loss of those over the age of 65 in the industrialized world. The prevalence and need to develop effective treatments for AMD has lead to the development of multiple animal models. AMD is a complex and heterogeneous disease that involves the interaction of both genetic and environmental factors with the unique anatomy of the human macula. Models in mice, rats, rabbits, pigs and non-human primates have recreated many of the histological features of AMD and provided much insight into the underlying pathological mechanisms of this disease. In spite of the large number of models developed, no one model yet recapitulates all of the features of human AMD. However, these models have helped reveal the roles of chronic oxidative damage, inflammation and immune dysregulation, and lipid metabolism in the development of AMD. Models for induced choroidal neovascularization have served as the backbone for testing new therapies. This article will review the diversity of animal models that exist for AMD as well as their strengths and limitations. PMID:22705444

  4. Deformation Models Tracking, Animation and Applications

    CERN Document Server

    Torres, Arnau; Gómez, Javier

    2013-01-01

    The computational modelling of deformations has been actively studied for the last thirty years. This is mainly due to its large range of applications that include computer animation, medical imaging, shape estimation, face deformation as well as other parts of the human body, and object tracking. In addition, these advances have been supported by the evolution of computer processing capabilities, enabling realism in a more sophisticated way. This book encompasses relevant works of expert researchers in the field of deformation models and their applications.  The book is divided into two main parts. The first part presents recent object deformation techniques from the point of view of computer graphics and computer animation. The second part of this book presents six works that study deformations from a computer vision point of view with a common characteristic: deformations are applied in real world applications. The primary audience for this work are researchers from different multidisciplinary fields, s...

  5. Animal models of compulsive eating behavior.

    Science.gov (United States)

    Di Segni, Matteo; Patrono, Enrico; Patella, Loris; Puglisi-Allegra, Stefano; Ventura, Rossella

    2014-10-22

    Eating disorders are multifactorial conditions that can involve a combination of genetic, metabolic, environmental, and behavioral factors. Studies in humans and laboratory animals show that eating can also be regulated by factors unrelated to metabolic control. Several studies suggest a link between stress, access to highly palatable food, and eating disorders. Eating "comfort foods" in response to a negative emotional state, for example, suggests that some individuals overeat to self-medicate. Clinical data suggest that some individuals may develop addiction-like behaviors from consuming palatable foods. Based on this observation, "food addiction" has emerged as an area of intense scientific research. A growing body of evidence suggests that some aspects of food addiction, such as compulsive eating behavior, can be modeled in animals. Moreover, several areas of the brain, including various neurotransmitter systems, are involved in the reinforcement effects of both food and drugs, suggesting that natural and pharmacological stimuli activate similar neural systems. In addition, several recent studies have identified a putative connection between neural circuits activated in the seeking and intake of both palatable food and drugs. The development of well-characterized animal models will increase our understanding of the etiological factors of food addiction and will help identify the neural substrates involved in eating disorders such as compulsive overeating. Such models will facilitate the development and validation of targeted pharmacological therapies.

  6. Animal Models of Compulsive Eating Behavior

    Directory of Open Access Journals (Sweden)

    Matteo Di Segni

    2014-10-01

    Full Text Available Eating disorders are multifactorial conditions that can involve a combination of genetic, metabolic, environmental, and behavioral factors. Studies in humans and laboratory animals show that eating can also be regulated by factors unrelated to metabolic control. Several studies suggest a link between stress, access to highly palatable food, and eating disorders. Eating “comfort foods” in response to a negative emotional state, for example, suggests that some individuals overeat to self-medicate. Clinical data suggest that some individuals may develop addiction-like behaviors from consuming palatable foods. Based on this observation, “food addiction” has emerged as an area of intense scientific research. A growing body of evidence suggests that some aspects of food addiction, such as compulsive eating behavior, can be modeled in animals. Moreover, several areas of the brain, including various neurotransmitter systems, are involved in the reinforcement effects of both food and drugs, suggesting that natural and pharmacological stimuli activate similar neural systems. In addition, several recent studies have identified a putative connection between neural circuits activated in the seeking and intake of both palatable food and drugs. The development of well-characterized animal models will increase our understanding of the etiological factors of food addiction and will help identify the neural substrates involved in eating disorders such as compulsive overeating. Such models will facilitate the development and validation of targeted pharmacological therapies.

  7. Animal Models Utilized in HTLV-1 Research

    Directory of Open Access Journals (Sweden)

    Amanda R. Panfil

    2013-01-01

    Full Text Available Since the isolation and discovery of human T-cell leukemia virus type 1 (HTLV-1 over 30 years ago, researchers have utilized animal models to study HTLV-1 transmission, viral persistence, virus-elicited immune responses, and HTLV-1-associated disease development (ATL, HAM/TSP. Non-human primates, rabbits, rats, and mice have all been used to help understand HTLV-1 biology and disease progression. Non-human primates offer a model system that is phylogenetically similar to humans for examining viral persistence. Viral transmission, persistence, and immune responses have been widely studied using New Zealand White rabbits. The advent of molecular clones of HTLV-1 has offered the opportunity to assess the importance of various viral genes in rabbits, non-human primates, and mice. Additionally, over-expression of viral genes using transgenic mice has helped uncover the importance of Tax and Hbz in the induction of lymphoma and other lymphocyte-mediated diseases. HTLV-1 inoculation of certain strains of rats results in histopathological features and clinical symptoms similar to that of humans with HAM/TSP. Transplantation of certain types of ATL cell lines in immunocompromised mice results in lymphoma. Recently, “humanized” mice have been used to model ATL development for the first time. Not all HTLV-1 animal models develop disease and those that do vary in consistency depending on the type of monkey, strain of rat, or even type of ATL cell line used. However, the progress made using animal models cannot be understated as it has led to insights into the mechanisms regulating viral replication, viral persistence, disease development, and, most importantly, model systems to test disease treatments.

  8. Cat Mammary Tumors: Genetic Models for the Human Counterpart

    Directory of Open Access Journals (Sweden)

    Filomena Adega

    2016-08-01

    Full Text Available The records are not clear, but Man has been sheltering the cat inside his home for over 12,000 years. The close proximity of this companion animal, however, goes beyond sharing the same roof; it extends to the great similarity found at the cellular and molecular levels. Researchers have found a striking resemblance between subtypes of feline mammary tumors and their human counterparts that goes from the genes to the pathways involved in cancer initiation and progression. Spontaneous cat mammary pre-invasive intraepithelial lesions (hyperplasias and neoplasias and malignant lesions seem to share a wide repertoire of molecular features with their human counterparts. In the present review, we tried to compile all the genetics aspects published (i.e., chromosomal alterations, critical cancer genes and their expression regarding cat mammary tumors, which support the cat as a valuable alternative in vitro cell and animal model (i.e., cat mammary cell lines and the spontaneous tumors, respectively, but also to present a critical point of view of some of the issues that really need to be investigated in future research.

  9. Pancreas tumor model in rabbit imaged by perfusion CT scans

    Science.gov (United States)

    Gunn, Jason; Tichauer, Kenneth; Moodie, Karen; Kane, Susan; Hoopes, Jack; Stewart, Errol E.; Hadway, Jennifer; Lee, Ting-Yim; Pereira, Stephen P.; Pogue, Brian W.

    2013-03-01

    The goal of this work was to develop and validate a pancreas tumor animal model to investigate the relationship between photodynamic therapy (PDT) effectiveness and photosensitizer drug delivery. More specifically, this work lays the foundation for investigating the utility of dynamic contrast enhanced blood perfusion imaging to be used to inform subsequent PDT. A VX2 carcinoma rabbit cell line was grown in the tail of the pancreas of three New Zealand White rabbits and approximately 3-4 weeks after implantation the rabbits were imaged on a CT scanner using a contrast enhanced perfusion protocol, providing parametric maps of blood flow, blood volume, mean transit time, and vascular permeability surface area product.

  10. Potential animal models of seasonal affective disorder.

    Science.gov (United States)

    Workman, Joanna L; Nelson, Randy J

    2011-01-01

    Seasonal affective disorder (SAD) is characterized by depressive episodes during winter that are alleviated during summer and by morning bright light treatment. Currently, there is no animal model of SAD. However, it may be possible to use rodents that respond to day length (photoperiod) to understand how photoperiod can shape the brain and behavior in humans. As nights lengthen in the autumn, the duration of the nightly elevation of melatonin increase; seasonally breeding animals use this information to orchestrate seasonal changes in physiology and behavior. SAD may originate from the extended duration of nightly melatonin secretion during fall and winter. These similarities between humans and rodents in melatonin secretion allows for comparisons with rodents that express more depressive-like responses when exposed to short day lengths. For instance, Siberian hamsters, fat sand rats, Nile grass rats, and Wistar rats display a depressive-like phenotype when exposed to short days. Current research in depression and animal models of depression suggests that hippocampal plasticity may underlie the symptoms of depression and depressive-like behaviors, respectively. It is also possible that day length induces structural changes in human brains. Many seasonally breeding rodents undergo changes in whole brain and hippocampal volume in short days. Based on strict validity criteria, there is no animal model of SAD, but rodents that respond to reduced day lengths may be useful to approximate the neurobiological phenomena that occur in people with SAD, leading to greater understanding of the etiology of the disorder as well as novel therapeutic interventions. Copyright © 2010 Elsevier Ltd. All rights reserved.

  11. An animal model to study regenerative endodontics.

    Science.gov (United States)

    Torabinejad, Mahmoud; Corr, Robert; Buhrley, Matthew; Wright, Kenneth; Shabahang, Shahrokh

    2011-02-01

    A growing body of evidence is demonstrating the possibility for regeneration of tissues within the pulp space and continued root development in teeth with necrotic pulps and open apices. There are areas of research related to regenerative endodontics that need to be investigated in an animal model. The purpose of this study was to investigate ferret cuspid teeth as a model to investigate factors involved in regenerative endodontics. Six young male ferrets between the ages of 36-133 days were used in this investigation. Each animal was anesthetized and perfused with 10% buffered formalin. Block sections including the mandibular and maxillary cuspid teeth and their surrounding periapical tissues were obtained, radiographed, decalcified, sectioned, and stained with hematoxylin-eosin to determine various stages of apical closure in these teeth. The permanent mandibular and maxillary cuspid teeth with open apices erupted approximately 50 days after birth. Initial signs of closure of the apical foramen in these teeth were observed between 90-110 days. Complete apical closure was observed in the cuspid teeth when the animals were 133 days old. Based on the experiment, ferret cuspid teeth can be used to investigate various factors involved in regenerative endodontics that cannot be tested in human subjects. The most appropriate time to conduct the experiments would be when the ferrets are between the ages of 50 and 90 days. Copyright © 2011. Published by Elsevier Inc.

  12. Halofuginone Inhibits Angiogenesis and Growth in Implanted Metastatic Rat Brain Tumor Model-an MRI Study

    Directory of Open Access Journals (Sweden)

    Rinat Abramovitch

    2004-09-01

    Full Text Available Tumor growth and metastasis depend on angiogenesis; therefore, efforts are made to develop specific angiogenic inhibitors. Halofuginone (HF is a potent inhibitor of collagen type α1(I. In solid tumor models, HF has a potent antitumor and antiangiogenic effect in vivo, but its effect on brain tumors has not yet been evaluated. By employing magnetic resonance imaging (MRI, we monitored the effect of HF on tumor progression and vascularization by utilizing an implanted malignant fibrous histiocytoma metastatic rat brain tumor model. Here we demonstrate that treatment with HF effectively and dose-dependently reduced tumor growth and angiogenesis. On day 13, HF-treated tumors were fivefold smaller than control (P < .001. Treatment with HF significantly prolonged survival of treated animals (142%; P = .001. In HF-treated rats, tumor vascularization was inhibited by 30% on day 13 and by 37% on day 19 (P < .05. Additionally, HF treatment inhibited vessel maturation (P = .03. Finally, in HF-treated rats, we noticed the appearance of a few clusters of satellite tumors, which were distinct from the primary tumor and usually contained vessel cores. This phenomenon was relatively moderate when compared to previous reports of other antiangiogenic agents used to treat brain tumors. We therefore conclude that HF is effective for treatment of metastatic brain tumors.

  13. Animal models for HIV/AIDS research

    Science.gov (United States)

    Hatziioannou, Theodora; Evans, David T.

    2015-01-01

    The AIDS pandemic continues to present us with unique scientific and public health challenges. Although the development of effective antiretroviral therapy has been a major triumph, the emergence of drug resistance requires active management of treatment regimens and the continued development of new antiretroviral drugs. Moreover, despite nearly 30 years of intensive investigation, we still lack the basic scientific knowledge necessary to produce a safe and effective vaccine against HIV-1. Animal models offer obvious advantages in the study of HIV/AIDS, allowing for a more invasive investigation of the disease and for preclinical testing of drugs and vaccines. Advances in humanized mouse models, non-human primate immunogenetics and recombinant challenge viruses have greatly increased the number and sophistication of available mouse and simian models. Understanding the advantages and limitations of each of these models is essential for the design of animal studies to guide the development of vaccines and antiretroviral therapies for the prevention and treatment of HIV-1 infection. PMID:23154262

  14. Analysis of animal experiments of radiation dependent tumor regression in relation to different parameters

    International Nuclear Information System (INIS)

    Heinzel, F.; Mueller-Duysing, W.; Blattman, H.; Bacesa, L.; Rao, K.R.; Mindek, G.

    In order to be able to test the therapeutic value of the pions in comparison with conventional X-rays, analyses of animal experiments with induced tumors, transplantation tumors, and comparative cellular kinetic studies of tissue cultures will be performed. So that differences in radiation effect and a possible superiority of the pion therapy be objectively acknowledged, the reaction systems to be tested must be as homogenous as possible. For this purpose, the dependence of the radiation related regression on various parameters such as sex, age of hosts, environmental factors radiation conditions (intensity, fractionation, and so on), tumor size, and so on, must be investigated on sterile animals in a sterile environment. The experiments should be conducted under conditions as close as possible to clinical ones. For comparison, the reaction of normal tissue (in vitro and in vivo) and of malignant cells in short-time tissue cultures will be analysed. Cellular kinetics, alteration of chromosomes and metabolic activity of the cells will be studied

  15. Experimental Oral Candidiasis in Animal Models

    Science.gov (United States)

    Samaranayake, Yuthika H.; Samaranayake, Lakshman P.

    2001-01-01

    Oral candidiasis is as much the final outcome of the vulnerability of the host as of the virulence of the invading organism. We review here the extensive literature on animal experiments mainly appertaining to the host predisposing factors that initiate and perpetuate these infections. The monkey, rat, and mouse are the choice models for investigating oral candidiasis, but comparisons between the same or different models appear difficult, because of variables such as the study design, the number of animals used, their diet, the differences in Candida strains, and the duration of the studies. These variables notwithstanding, the following could be concluded. (i) The primate model is ideal for investigating Candida-associated denture stomatitis since both erythematous and pseudomembranous lesions have been produced in monkeys with prosthetic plates; they are, however, expensive and difficult to obtain and maintain. (ii) The rat model (both Sprague-Dawley and Wistar) is well proven for observing chronic oral candidal colonization and infection, due to the ease of breeding and handling and their ready availability. (iii) Mice are similar, but in addition there are well characterized variants simulating immunologic and genetic abnormalities (e.g., athymic, euthymic, murine-acquired immune deficiency syndrome, and severe combined immunodeficient models) and hence are used for short-term studies relating the host immune response and oral candidiasis. Nonetheless, an ideal, relatively inexpensive model representative of the human oral environment in ecological and microbiological terms is yet to be described. Until such a model is developed, researchers should pay attention to standardization of the experimental protocols described here to obtain broadly comparable and meaningful data. PMID:11292645

  16. Brain Tumor Segmentation Using a Generative Model with an RBM Prior on Tumor Shape

    DEFF Research Database (Denmark)

    Agn, Mikael; Puonti, Oula; Rosenschöld, Per Munck af

    2016-01-01

    In this paper, we present a fully automated generative method for brain tumor segmentation in multi-modal magnetic resonance images. The method is based on the type of generative model often used for segmenting healthy brain tissues, where tissues are modeled by Gaussian mixture models combined...... with a spatial atlas-based tissue prior. We extend this basic model with a tumor prior, which uses convolutional restricted Boltzmann machines (cRBMs) to model the shape of both tumor core and complete tumor, which includes edema and core. The cRBMs are trained on expert segmentations of training images, without...

  17. Tumorer

    DEFF Research Database (Denmark)

    Prause, J.U.; Heegaard, S.

    2005-01-01

    oftalmologi, øjenlågstumorer, conjunctivale tumorer, malignt melanom, retinoblastom, orbitale tumorer......oftalmologi, øjenlågstumorer, conjunctivale tumorer, malignt melanom, retinoblastom, orbitale tumorer...

  18. Mefenamic Acid Induced Nephrotoxicity: An Animal Model

    Directory of Open Access Journals (Sweden)

    Muhammad Nazrul Somchit

    2014-12-01

    Full Text Available Purpose: Nonsteroidal anti-inflammatory drugs (NSAIDs are used for the treatment of many joint disorders, inflammation and to control pain. Numerous reports have indicated that NSAIDs are capable of producing nephrotoxicity in human. Therefore, the objective of this study was to evaluate mefenamic acid, a NSAID nephrotoxicity in an animal model. Methods: Mice were dosed intraperitoneally with mefenamic acid either as a single dose (100 or 200 mg/kg in 10% Dimethyl sulfoxide/Palm oil or as single daily doses for 14 days (50 or 100 mg/kg in 10% Dimethyl sulfoxide/Palm oil per day. Venous blood samples from mice during the dosing period were taken prior to and 14 days post-dosing from cardiac puncture into heparinized vials. Plasma blood urea nitrogen (BUN and creatinine activities were measured. Results: Single dose of mefenamic acid induced mild alteration of kidney histology mainly mild glomerular necrosis and tubular atrophy. Interestingly, chronic doses induced a dose dependent glomerular necrosis, massive degeneration, inflammation and tubular atrophy. Plasma blood urea nitrogen was statistically elevated in mice treated with mefenamic acid for 14 days similar to plasma creatinine. Conclusion: Results from this study suggest that mefenamic acid as with other NSAIDs capable of producing nephrotoxicity. Therefore, the study of the exact mechanism of mefenamic acid induced severe nephrotoxicity can be done in this animal model.

  19. Small-Animal Models of Zika Virus.

    Science.gov (United States)

    Julander, Justin G; Siddharthan, Venkatraman

    2017-12-16

    Zika virus (ZIKV) infection can result in serious consequences, including severe congenital manifestations, persistent infection in the testes, and neurologic sequelae. After a pandemic emergence, the virus has spread to much of North and South America and has been introduced to many countries outside of ZIKV-endemic areas as infected travelers return to their home countries. Rodent models have been important in gaining a better understanding of the wide range of disease etiologies associated with ZIKV infection and for the initial phase of developing countermeasures to prevent or treat viral infections. We discuss herein the advantages and disadvantages of small-animal models that have been developed to replicate various aspects of disease associated with ZIKV infection. © The Author(s) 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  20. Biokinetic models for radionuclides in experimental animals

    International Nuclear Information System (INIS)

    Morcillo, M. A.

    2003-01-01

    The biokinetic models for many radionuclides are, to a large extent, based on data obtained in experimental animals. The methods used in the experimental development of a biokinetic model can be classified in two groups (i) those applied during the experimental work, which include the activity determination of a given radionuclide at different times and in different biological media such as blood, serum, organs/tissues, urine, bile and faeces and (ii) those methods used for the analysis and study of the experimental data, based in mathematical tools. Some of these methods are reviewed,with special emphasis in the whole body macro autoradiography. To conclude, the contribution that this type of studies can have in two fields of radiation protection is discussed, namely optimization of dosimetric evaluations and decorporation of radionuclides. (Author)

  1. Advances in transgenic animal models and techniques.

    Science.gov (United States)

    Ménoret, Séverine; Tesson, Laurent; Remy, Séverine; Usal, Claire; Ouisse, Laure-Hélène; Brusselle, Lucas; Chenouard, Vanessa; Anegon, Ignacio

    2017-10-01

    On May 11th and 12th 2017 was held in Nantes, France, the international meeting "Advances in transgenic animal models and techniques" ( http://www.trm.univ-nantes.fr/ ). This biennial meeting is the fifth one of its kind to be organized by the Transgenic Rats ImmunoPhenomic (TRIP) Nantes facility ( http://www.tgr.nantes.inserm.fr/ ). The meeting was supported by private companies (SONIDEL, Scionics computer innovation, New England Biolabs, MERCK, genOway, Journal Disease Models and Mechanisms) and by public institutions (International Society for Transgenic Technology, University of Nantes, INSERM UMR 1064, SFR François Bonamy, CNRS, Région Pays de la Loire, Biogenouest, TEFOR infrastructure, ITUN, IHU-CESTI and DHU-Oncogeffe and Labex IGO). Around 100 participants, from France but also from different European countries, Japan and USA, attended the meeting.

  2. Animal Models of Dengue Virus Infection

    Directory of Open Access Journals (Sweden)

    Eva Harris

    2012-01-01

    Full Text Available The development of animal models of dengue virus (DENV infection and disease has been challenging, as epidemic DENV does not naturally infect non-human species. Non-human primates (NHPs can sustain viral replication in relevant cell types and develop a robust immune response, but they do not develop overt disease. In contrast, certain immunodeficient mouse models infected with mouse-adapted DENV strains show signs of severe disease similar to the ‘vascular-leak’ syndrome seen in severe dengue in humans. Humanized mouse models can sustain DENV replication and show some signs of disease, but further development is needed to validate the immune response. Classically, immunocompetent mice infected with DENV do not manifest disease or else develop paralysis when inoculated intracranially; however, a new model using high doses of DENV has recently been shown to develop hemorrhagic signs after infection. Overall, each model has its advantages and disadvantages and is differentially suited for studies of dengue pathogenesis and immunopathogenesis and/or pre-clinical testing of antiviral drugs and vaccines.

  3. MR Vascular Fingerprinting in Stroke and Brain Tumors Models.

    Science.gov (United States)

    Lemasson, B; Pannetier, N; Coquery, N; Boisserand, Ligia S B; Collomb, Nora; Schuff, N; Moseley, M; Zaharchuk, G; Barbier, E L; Christen, T

    2016-11-24

    In this study, we evaluated an MRI fingerprinting approach (MRvF) designed to provide high-resolution parametric maps of the microvascular architecture (i.e., blood volume fraction, vessel diameter) and function (blood oxygenation) simultaneously. The method was tested in rats (n = 115), divided in 3 models: brain tumors (9 L, C6, F98), permanent stroke, and a control group of healthy animals. We showed that fingerprinting can robustly distinguish between healthy and pathological brain tissues with different behaviors in tumor and stroke models. In particular, fingerprinting revealed that C6 and F98 glioma models have similar signatures while 9 L present a distinct evolution. We also showed that it is possible to improve the results of MRvF and obtain supplemental information by changing the numerical representation of the vascular network. Finally, good agreement was found between MRvF and conventional MR approaches in healthy tissues and in the C6, F98, and permanent stroke models. For the 9 L glioma model, fingerprinting showed blood oxygenation measurements that contradict results obtained with a quantitative BOLD approach. In conclusion, MR vascular fingerprinting seems to be an efficient technique to study microvascular properties in vivo. Multiple technical improvements are feasible and might improve diagnosis and management of brain diseases.

  4. The role of bisphosphonates in breast cancer: Actions of bisphosphonates in animal models of breast cancer

    Science.gov (United States)

    Padalecki, Susan S; Guise, Theresa A

    2002-01-01

    The skeleton is the most common site of breast cancer metastases. These bone metastases are usually osteolytic and cause significant morbidity. Bisphosphonates, potent inhibitors of bone resorption, reduce skeletal morbidity in breast cancer patients with bone metastases. Animal studies with bisphosphonates are crucial to understanding the mechanisms by which these compounds affect bone and tumor cells in vivo. Such animal models of breast cancer that are used to test the efficacy of bisphosphonates are discussed. These studies may offer insight into the treatment of other tumor types that frequently metastasize to bone. PMID:11879558

  5. [Analysis of dalbavancin in animal models].

    Science.gov (United States)

    Murillo, Óscar; El-Haj, Cristina

    2017-01-01

    Multiresistant Gram-positive infections continue to pose a major clinical challenge and the development of new antibiotics is always desirable. Dalbavancin is a lipoglycopeptide with a prolonged half-life that allows long dosing intervals. In experimental models, its activity has been evaluated in distinct models and microorganisms, which limits the conclusions that can be drawn; however, the largest number of studies have been conducted in Staphylococcus aureus infection. Overall, dalbavancin has shown concentration-dependent efficacy and the parameters best explaining its activity are maximal pharmacodynamic concentration/minimal inhibitory concentration and the area under the curve/minimal inhibitory concentration. In these experimental models, dalbavancin has shown good distribution, a prolonged half-life in all animal species and efficacy that is mostly similar to that of previous glycopeptides but with lower doses and with longer dosing intervals. Of note, the efficacy of dalbavancin is not altered by methicillin resistance or the glycopeptide sensitivity of S. aureus. In the case of difficult-to-treat staphylococcal infections (eg, endocarditis, foreign body infections), an adequate dosing interval and high dosage seem to play an important role in the efficacy of the drug. All in all, experimental models can still provide greater knowledge of this new antibiotic to guide clinical research and determine its role in the treatment of distinct infections produced by Gram-positive microorganisms. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

  6. Animal models of chronic wound care

    DEFF Research Database (Denmark)

    Trøstrup, Hannah; Thomsen, Kim; Calum, Henrik

    2016-01-01

    Chronic wounds are a substantial clinical problem affecting millions of people worldwide. Pathophysiologically, chronic wounds are stuck in the inflammatory state of healing. The role of bacterial biofilms in suppression and perturbation of host response could be an explanation for this observation....... An inhibiting effect of bacterial biofilms on wound healing is gaining significant clinical attention over the last few years. There is still a paucity of suitable animal models to recapitulate human chronic wounds. The etiology of the wound (venous insufficiency, ischemia, diabetes, pressure) has to be taken...... into consideration as underlying pathophysiological mechanisms and comorbidities display tremendous variation in humans. Confounders such as infection, smoking, chronological age, sex, medication, metabolic disturbances, and renal impairment add to the difficulty in gaining systematic and comparable studies...

  7. Animal models for HCV and HBV studies

    Directory of Open Access Journals (Sweden)

    Isabelle Chemin

    2007-02-01

    Full Text Available

    The narrow host range of infection and lack of suitable tissue culture systems for the propagation of hepatitis B and C viruses are limitations that have prevented a more thorough understanding of persistent infection and the pathogenesis of chronic liver disease.

    Despite decades of intensive research and significant progresses in understanding of viral hepatitis, many basic questions and clinical problems still await to be resolved. For example, the HBV cellular receptor and related mechanisms of viral entry have not yet been identified. Little is also known about the function of certain non-structural viral products, such as the hepatitis B e antigen and the X protein, or about the role of excess hepadnavirus subviral particles circulating in the blood stream during infection. Furthermore, the molecular mechanisms involved in the development of hepatocellular carcinoma and the role of the immune system in determining the fate of infection are not fully understood.

    The reason for these drawbacks is essentially due to the lack of reliable cell-based in vitro infection systems and, most importantly, convenient animal models.

    This lack of knowledge has been partially overcome for hepatitis B virus (HBV, by the discovery and characterization of HBV-like viruses in wild animals while for hepatitis C virus (HCV, related flaviviruses have been used as surrogate systems.

    Other laboratories have developed transgenic mice that express virus gene products and/or support virus replication. Some HBV transgenic mouse models

  8. Protective effects of dendrosomal curcumin on an animal metastatic breast tumor.

    Science.gov (United States)

    Farhangi, Baharak; Alizadeh, Ali Mohammad; Khodayari, Hamid; Khodayari, Saeed; Dehghan, Mohammad Javad; Khori, Vahid; Heidarzadeh, Alemeh; Khaniki, Mahmood; Sadeghiezadeh, Majid; Najafi, Farhood

    2015-07-05

    Curcumin has been shown to inhibit migration and invasion of cancer angiogenesis via interacting with key regulatory molecules like NF-κB. Rapidly metabolized and conjugated in the liver, curcumin has the limited systemic bioavailability. Previous results have shown a new light of potential biocompatibility, biodegradability, as well as anti-cancer effects of dendrosomal curcumin (DNC) in biological systems. The present study aims to deliberate the protective effects of DNC on metastatic breast tumor in vitro and in vivo. After the dosing procedure, twenty-seven female mice were divided into 40 and 80mg/kg groups of DNC, along with a control group to investigate the anti-metastatic effects of DNC on mammary tumor-bearing mice. In vitro results showed that the different concentrations of DNC reduced the migration and the adhesion of 4T1 cells after 24h (PDNC was safe at 80mg/kg and lower doses. The treated DNC animals had a higher survival rate and lower metastatic signs (14%) compared to control (100%) (PDNC had smaller tumor volume in comparison with control group (PDNC groups, respectively (PDNC led to down-regulation of VEGF, COX-2, and MMP-9 expressions in the breast tumor, the lung, the brain, the spleen and the liver tissues (P<0.05). These outcomes indicate that dendrosomal curcumin has a chemoprotective effect on the breast cancer metastasis through suppression of NF-κB and its regulated gene products. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Inhibition of tumor growth in a glioma model treated with boron neutron capture therapy

    International Nuclear Information System (INIS)

    Goodman, J.H.; McGregor, J.M.; Clendenon, N.R.; Gahbauer, R.A.; Barth, R.F.; Soloway, A.H.; Fairchild, R.G.

    1990-01-01

    This investigation attempts to determine whether increased survival time seen when the F98 glioma model is treated with boron neutron capture therapy (BNCT) is a result of inhibition of tumor growth caused by radiation-induced alterations in endothelial cells and normal tissue components. This indirect effect of radiation has been called the tumor bed effect. A series of tumor-bearing rats was studied, using a standardized investigational BNCT protocol consisting of 50 mg/kg of Na2B12H11SH injected intravenously 14 to 17 hours before neutron irradiation at 4 x 10(12) n/cm2. Ten rats, serving as controls, received no treatment either before or after tumor implantation. A second group of 10 rats was treated with BNCT 4 days before tumor implantation; these animals received no further treatment. The remaining group of 10 rats received no pretreatment but was treated with BNCT 10 days after implantation. Histological and ultrastructural analyses were performed in 2 animals from each group 17 days after implantation. Survival times of the untreated control animals (mean, 25.8 days) did not differ statistically from the survival times of the rats in the pretreated group (mean, 25.5 days). The rats treated with BNCT after implantation survived significantly longer (P less than 0.02; mean, 33.2 days) than the controls and the preirradiated animals. Tumor size indices calculated from measurements taken at the time of death were similar in all groups. These results indicate that, with this tumor model, BNCT does not cause a tumor bed effect in cerebral tissue. The therapeutic gains observed with BNCT result from direct effects on tumor cells or on the peritumoral neovascularity

  10. Ethical guidelines, animal profile, various animal models used in periodontal research with alternatives and future perspectives

    Directory of Open Access Journals (Sweden)

    Mohan Kumar Pasupuleti

    2016-01-01

    Full Text Available Laboratory animal models serve as a facilitator to investigate the etiopathogenesis of periodontal disease, are used to know the efficacy of reconstructive and regenerative procedures, and are also helpful in evaluation of newer therapeutic techniques including laser and implant therapies prior to application in the human beings. The aim of this review is to know the different animal models used in various specialties of dental research and to know the ethical guidelines prior to the usage of experimental models with main emphasis on how to refine, replace, and reduce the number of animal models usage in the laboratory. An online search for experimental animal models used in dental research was performed using MEDLINE/PubMed database. Publications from 2009 to May 2013 in the specialty of periodontics were included in writing this review. A total of 652 references were published in PubMed/MEDLINE databases based on the search terms used. Out of 245 studies, 241 were related to the periodontal research published in English from 2009 to 2013. Relevant papers were chosen according to the inclusion and exclusion criteria. After extensive electronic and hand search on animal models, it has been observed that various animal models were used in dental research. Search on animal models used for dental research purpose revealed that various animals such as rats, mice, guinea pigs, rabbit, beagle dogs, goats, and nonhuman primates were extensively used. However, with the new advancement of ex vivo animal models, it has become easy to investigate disease pathogenesis and to test the efficacy of newer therapeutic modalities with the reduced usage of animal models. This review summarized the large amount of literature on animal models used in periodontal research with main emphasis on ethical guidelines and on reducing the animal model usage in future perspective.

  11. {sup 131}I-CRTX internal dosimetry: animal model and human extrapolation

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Henrique Martins de; Ferreira, Andrea Vidal; Soares, Marcella Araugio; Silveira, Marina Bicalho; Santos, Raquel Gouvea dos [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN-CNEN-MG), Belo Horizonte, MG (Brazil)], e-mail: hma@cdtn.br

    2009-07-01

    Snake venoms molecules have been shown to play a role not only in the survival and proliferation of tumor cells but also in the processes of tumor cell adhesion, migration and angiogenesis. {sup 125}I-Crtx, a radiolabeled version of a peptide derived from Crotalus durissus terrificus snake venom, specifically binds to tumor and triggers apoptotic signalling. At the present work, {sup 125}I-Crtx biokinetic data (evaluated in mice bearing Erlich tumor) were treated by MIRD formalism to perform Internal Dosimetry studies. Doses in several organs of mice were determinate, as well as in implanted tumor, for {sup 131}I-Crtx. Doses results obtained for animal model were extrapolated to humans assuming a similar concentration ratio among various tissues between mouse and human. In the extrapolation, it was used human organ masses from Cristy/Eckerman phantom. Both penetrating and non-penetrating radiation from {sup 131}I in the tissue were considered in dose calculations. (author)

  12. 131I-CRTX internal dosimetry: animal model and human extrapolation

    International Nuclear Information System (INIS)

    Andrade, Henrique Martins de; Ferreira, Andrea Vidal; Soares, Marcella Araugio; Silveira, Marina Bicalho; Santos, Raquel Gouvea dos

    2009-01-01

    Snake venoms molecules have been shown to play a role not only in the survival and proliferation of tumor cells but also in the processes of tumor cell adhesion, migration and angiogenesis. 125 I-Crtx, a radiolabeled version of a peptide derived from Crotalus durissus terrificus snake venom, specifically binds to tumor and triggers apoptotic signalling. At the present work, 125 I-Crtx biokinetic data (evaluated in mice bearing Erlich tumor) were treated by MIRD formalism to perform Internal Dosimetry studies. Doses in several organs of mice were determinate, as well as in implanted tumor, for 131 I-Crtx. Doses results obtained for animal model were extrapolated to humans assuming a similar concentration ratio among various tissues between mouse and human. In the extrapolation, it was used human organ masses from Cristy/Eckerman phantom. Both penetrating and non-penetrating radiation from 131 I in the tissue were considered in dose calculations. (author)

  13. Animal Model of Acute Deep Vein Thrombosis

    International Nuclear Information System (INIS)

    Roy, Sumit; Laerum, Frode; Brosstad, Frank; Kvernebo, Knut; Sakariassen, Kjell S.

    1998-01-01

    Purpose: To develop an animal model of acute deep vein thrombosis (DVT). Methods: In part I of the study nine juvenile domestic pigs were used. Each external iliac vein was transluminally occluded with a balloon catheter. Thrombin was infused through a microcatheter in one leg according to one of the following protocols: (1) intraarterial (IA): 1250 U at 25 U/min in the common femoral artery (n= 3); (2) intravenous (IV): 5000 U in the popliteal vein at 500 U/min (n= 3), or at 100 U/min (n= 3). Saline was administered in the opposite leg. After the animals were killed, the mass of thrombus in the iliofemoral veins was measured. The pudendoepiploic (PEV), profunda femoris (PF), and popliteal veins (PV) were examined. Thrombosis in the tributaries of the superficial femoral vein (SFVt) was graded according to a three-point scale (0, +, ++). In part II of the study IV administration was further investigated in nine pigs using the following three regimens with 1000 U at 25 U/min serving as the control: (1) 1000 U at 100 U/min, (2) 250 U at 25 U/min, (3) 250 U at 6.25 U/min. Results: All animals survived. In part I median thrombus mass in the test limbs was 1.40 g as compared with 0.25 g in the controls (p= 0.01). PEV, PFV and PV were thrombosed in all limbs infused with thrombin. IV infusion was more effective in inducing thrombosis in both the parent veins (mass 1.32-1.78 g) and SVFt (++ in 4 of 6 legs), as compared with IA infusion (mass 0.0-1.16 g; SFVt ++ in 1 of 3 legs). In part II thrombus mass in axial veins ranged from 1.23 to 2.86 g, and showed no relationship with the dose of thrombin or the rate of infusion. Tributary thrombosis was less extensive with 250 U at 25 U/min than with the other regimens. Conclusion: Slow distal intravenous thrombin infusion in the hind legs of pigs combined with proximal venous occlusion induces thrombosis in the leg veins that closely resembles clinical DVT in distribution

  14. Microencapsulated tumor assay: Evaluation of the nude mouse model of pancreatic cancer

    Science.gov (United States)

    Ma, Ming-Zhe; Cheng, Dong-Feng; Ye, Jin-Hua; Zhou, Yong; Wang, Jia-Xiang; Shi, Min-Min; Han, Bao-San; Peng, Cheng-Hong

    2012-01-01

    displayed an obvious advantage in tumor mass (4th wk: 0.0461 ± 0.0399 vs 0.0313 ± 0.021, t = -0.81, P = 0.4379; 8th wk: 0.1284 ± 0.0284 vs 0.0943 ± 0.0571, t = -2.28, respectively, P = 0.0457) compared with the latter in the orthotopic implantation model. CONCLUSION: Encapsulation of pancreatic tumor cells is a reliable method for establishing a pancreatic tumor animal model. PMID:22294829

  15. Mathematical models of tumor growth: translating absorbed dose to tumor control probability

    International Nuclear Information System (INIS)

    Sgouros, G.

    1996-01-01

    Full text: The dose-rate in internal emitter therapy is low and time-dependent as compared to external beam radiotherapy. Once the total absorbed dose delivered to a target tissue is calculated, however, most dosimetric analyses of radiopharmaceuticals are considered complete. To translate absorbed dose estimates obtained for internal emitter therapy to biologic effect, the growth characteristics, repair capacity, and radiosensitivity of the tumor must be considered. Tumor growth may be represented by the Gompertz equation in which tumor cells increase at an exponential growth rate that is itself decreasing at an exponential rate; as the tumor increases in size, the growth rate diminishes. The empirical Gompertz expression for tumor growth may be derived from a mechanistic model in which growth is represented by a balance between tumor-cell birth and loss. The birth rate is assumed to be fixed, while the cell loss rate is time-dependent and increases with tumor size. The birth rate of the tumors may be related to their potential doubling time. Multiple biopsies of individual tumors have demonstrated a heterogeneity in the potential doubling time of tumors. By extending the mechanistic model described above to allow for sub-populations of tumor cells with different birth rates, the effect of kinetic heterogeneity within a tumor may be examined. Model simulations demonstrate that the cell kinetic parameters of a tumor are predicted to change over time and measurements obtained using a biopsy are unlikely to reflect the kinetics of the tumor throughout its growth history. A decrease in overall tumor mass, in which each sub-population is reduced in proportion to its cell number, i.e., the log-kill assumption, leads to re-growth of a tumor that has a greater proliferation rate. Therapy that is linked to the potential doubling time or to the effective proliferation rate of the tumor may lead to re-growth of a tumor that is kinetically unchanged. The simplest model of

  16. RASopathies: unraveling mechanisms with animal models

    Directory of Open Access Journals (Sweden)

    Granton A. Jindal

    2015-08-01

    Full Text Available RASopathies are developmental disorders caused by germline mutations in the Ras-MAPK pathway, and are characterized by a broad spectrum of functional and morphological abnormalities. The high incidence of these disorders (∼1/1000 births motivates the development of systematic approaches for their efficient diagnosis and potential treatment. Recent advances in genome sequencing have greatly facilitated the genotyping and discovery of mutations in affected individuals, but establishing the causal relationships between molecules and disease phenotypes is non-trivial and presents both technical and conceptual challenges. Here, we discuss how these challenges could be addressed using genetically modified model organisms that have been instrumental in delineating the Ras-MAPK pathway and its roles during development. Focusing on studies in mice, zebrafish and Drosophila, we provide an up-to-date review of animal models of RASopathies at the molecular and functional level. We also discuss how increasingly sophisticated techniques of genetic engineering can be used to rigorously connect changes in specific components of the Ras-MAPK pathway with observed functional and morphological phenotypes. Establishing these connections is essential for advancing our understanding of RASopathies and for devising rational strategies for their management and treatment.

  17. Dynamic {sup 11}C-methionine PET analysis has an additional value for differentiating malignant tumors from granulomas: an experimental study using small animal PET

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Songji; Zhao, Yan [Hokkaido University, Department of Nuclear Medicine, Graduate School of Medicine, Sapporo (Japan); Hokkaido University, Department of Tracer Kinetics and Bioanalysis, Graduate School of Medicine, Sapporo (Japan); Kuge, Yuji; Hatano, Toshiyuki [Hokkaido University, Central Institute of Isotope Science, Sapporo (Japan); Yi, Min; Kohanawa, Masashi [Hokkaido University, Department of Advanced Medicine, Graduate School of Medicine, Sapporo (Japan); Magota, Keiichi; Tamaki, Nagara [Hokkaido University, Department of Nuclear Medicine, Graduate School of Medicine, Sapporo (Japan); Nishijima, Ken-ichi [Hokkaido University, Department of Molecular Imaging, Graduate School of Medicine, Sapporo (Japan)

    2011-10-15

    We evaluated whether the dynamic profile of L-{sup 11}C-methionine ({sup 11}C-MET) may have an additional value in differentiating malignant tumors from granulomas in experimental rat models by small animal positron emission tomography (PET). Rhodococcus aurantiacus and allogenic rat C6 glioma cells were inoculated, respectively, into the right and left calf muscles to generate a rat model bearing both granulomas and tumors (n = 6). Ten days after the inoculations, dynamic {sup 11}C-MET PET was performed by small animal PET up to 120 min after injection of {sup 11}C-MET. The next day, after overnight fasting, the rats were injected with {sup 18}F-2-deoxy-2-fluoro-D-glucose ({sup 18}F-FDG), and dynamic {sup 18}F-FDG PET was performed up to 180 min. The time-activity curves, static images, and mean standardized uptake value (SUV) in the lesions were calculated. {sup 11}C-MET uptake in the granuloma showed a slow exponential clearance after an initial distribution, while the uptake in the tumor gradually increased with time. The dynamic pattern of {sup 11}C-MET uptake in the granuloma was significantly different from that in the tumor (p < 0.001). In the static analysis of {sup 11}C-MET, visual assessment and SUV analysis could not differentiate the tumor from the granuloma in all cases, although the mean SUV in the granuloma (1.48 {+-} 0.09) was significantly lower than that in the tumor (1.72 {+-} 0.18, p < 0.01). The dynamic patterns, static images, and mean SUVs of {sup 18}F-FDG in the granuloma were similar to those in the tumor (p = NS). Dynamic {sup 11}C-MET PET has an additional value for differentiating malignant tumors from granulomatous lesions, which deserves further elucidation in clinical settings. (orig.)

  18. A Multimodal Imaging Approach for Longitudinal Evaluation of Bladder Tumor Development in an Orthotopic Murine Model.

    Directory of Open Access Journals (Sweden)

    Chantal Scheepbouwer

    Full Text Available Bladder cancer is the fourth most common malignancy amongst men in Western industrialized countries with an initial response rate of 70% for the non-muscle invasive type, and improving therapy efficacy is highly needed. For this, an appropriate, reliable animal model is essential to gain insight into mechanisms of tumor growth for use in response monitoring of (new agents. Several animal models have been described in previous studies, but so far success has been hampered due to the absence of imaging methods to follow tumor growth non-invasively over time. Recent developments of multimodal imaging methods for use in animal research have substantially strengthened these options of in vivo visualization of tumor growth. In the present study, a multimodal imaging approach was addressed to investigate bladder tumor proliferation longitudinally. The complementary abilities of Bioluminescence, High Resolution Ultrasound and Photo-acoustic Imaging permit a better understanding of bladder tumor development. Hybrid imaging modalities allow the integration of individual strengths to enable sensitive and improved quantification and understanding of tumor biology, and ultimately, can aid in the discovery and development of new therapeutics.

  19. Therapeutic Implications from Sensitivity Analysis of Tumor Angiogenesis Models

    Science.gov (United States)

    Poleszczuk, Jan; Hahnfeldt, Philip; Enderling, Heiko

    2015-01-01

    Anti-angiogenic cancer treatments induce tumor starvation and regression by targeting the tumor vasculature that delivers oxygen and nutrients. Mathematical models prove valuable tools to study the proof-of-concept, efficacy and underlying mechanisms of such treatment approaches. The effects of parameter value uncertainties for two models of tumor development under angiogenic signaling and anti-angiogenic treatment are studied. Data fitting is performed to compare predictions of both models and to obtain nominal parameter values for sensitivity analysis. Sensitivity analysis reveals that the success of different cancer treatments depends on tumor size and tumor intrinsic parameters. In particular, we show that tumors with ample vascular support can be successfully targeted with conventional cytotoxic treatments. On the other hand, tumors with curtailed vascular support are not limited by their growth rate and therefore interruption of neovascularization emerges as the most promising treatment target. PMID:25785600

  20. Framework for hyperspectral image processing and quantification for cancer detection during animal tumor surgery

    Science.gov (United States)

    Lu, Guolan; Wang, Dongsheng; Qin, Xulei; Halig, Luma; Muller, Susan; Zhang, Hongzheng; Chen, Amy; Pogue, Brian W.; Chen, Zhuo Georgia; Fei, Baowei

    2015-01-01

    Abstract. Hyperspectral imaging (HSI) is an imaging modality that holds strong potential for rapid cancer detection during image-guided surgery. But the data from HSI often needs to be processed appropriately in order to extract the maximum useful information that differentiates cancer from normal tissue. We proposed a framework for hyperspectral image processing and quantification, which includes a set of steps including image preprocessing, glare removal, feature extraction, and ultimately image classification. The framework has been tested on images from mice with head and neck cancer, using spectra from 450- to 900-nm wavelength. The image analysis computed Fourier coefficients, normalized reflectance, mean, and spectral derivatives for improved accuracy. The experimental results demonstrated the feasibility of the hyperspectral image processing and quantification framework for cancer detection during animal tumor surgery, in a challenging setting where sensitivity can be low due to a modest number of features present, but potential for fast image classification can be high. This HSI approach may have potential application in tumor margin assessment during image-guided surgery, where speed of assessment may be the dominant factor. PMID:26720879

  1. Framework for hyperspectral image processing and quantification for cancer detection during animal tumor surgery.

    Science.gov (United States)

    Lu, Guolan; Wang, Dongsheng; Qin, Xulei; Halig, Luma; Muller, Susan; Zhang, Hongzheng; Chen, Amy; Pogue, Brian W; Chen, Zhuo Georgia; Fei, Baowei

    2015-01-01

    Hyperspectral imaging (HSI) is an imaging modality that holds strong potential for rapid cancer detection during image-guided surgery. But the data from HSI often needs to be processed appropriately in order to extract the maximum useful information that differentiates cancer from normal tissue. We proposed a framework for hyperspectral image processing and quantification, which includes a set of steps including image preprocessing, glare removal, feature extraction, and ultimately image classification. The framework has been tested on images from mice with head and neck cancer, using spectra from 450- to 900-nm wavelength. The image analysis computed Fourier coefficients, normalized reflectance, mean, and spectral derivatives for improved accuracy. The experimental results demonstrated the feasibility of the hyperspectral image processing and quantification framework for cancer detection during animal tumor surgery, in a challenging setting where sensitivity can be low due to a modest number of features present, but potential for fast image classification can be high. This HSI approach may have potential application in tumor margin assessment during image-guided surgery, where speed of assessment may be the dominant factor.

  2. Clinical Trials of Immunogene Therapy for Spontaneous Tumors in Companion Animals

    Science.gov (United States)

    Glikin, Gerardo Claudio; Finocchiaro, Liliana María Elena

    2014-01-01

    Despite the important progress obtained in the treatment of some pets' malignancies, new treatments need to be developed. Being critical in cancer control and progression, the immune system's appropriate modulation may provide effective therapeutic options. In this review we summarize the outcomes of published immunogene therapy veterinary clinical trials reported by many research centers. A variety of tumors such as canine melanoma, soft tissue sarcomas, osteosarcoma and lymphoma, feline fibrosarcoma, and equine melanoma were subjected to different treatment approaches. Both viral and mainly nonviral vectors were used to deliver gene products as cytokines, xenogeneic tumor associated antigens, specific ligands, and proapoptotic regulatory factors. In some cases autologous, allogenic, or xenogeneic transgenic cytokine producing cells were assayed. In general terms, minor or no adverse collateral effects appeared during this kind of therapies and treated patients usually displayed a better course of the disease (longer survival, delayed or suppressed recurrence or metastatic spread, and improvement of the quality of life). This suggests the utility of these methodologies as standard adjuvant treatments. The encouraging outcomes obtained in companion animals support their ready application in veterinary clinical oncology and serve as preclinical proof of concept and safety assay for future human gene therapy trials. PMID:25506617

  3. Wound healing in animal models: review article

    Directory of Open Access Journals (Sweden)

    Fariba Jaffary

    2017-10-01

    Full Text Available Wound healing and reduction of its recovery time is one of the most important issues in medicine. Wound is defined as disruption of anatomy and function of normal skin. This injury could be the result of physical elements such as  surgical incision, hit or pressure cut of the skin and gunshot wound. Chemical or caustic burn is another category of wound causes that can be induced by acid or base contact irritation. Healing is a process of cellular and extracellular matrix interactions that occur in the damaged tissue. Wound healing consists of several stages including hemostasis, inflammatory phase, proliferative phase and new tissue formation which reconstructs by new collagen formation. Wounds are divided into acute and chronic types based on their healing time. Acute wounds have sudden onset and in normal individuals usually have healing process of less than 4 weeks without any residual side effects. In contrast, chronic wounds have gradual onset. Their inflammatory phase is prolonged and the healing process is stopped due to some background factors like diabetes, ischemia or local pressure. If the healing process lasts more than 4 weeks it will be classified as chronic wound. Despite major advances in the treatment of wounds, still finding effective modalities for healing wounds in the shortest possible time with the fewest side effects is a current challenge. In this review different phases of wound healing and clinical types of wound such as venous leg ulcer, diabetic foot ulcer and pressure ulcer are discussed. Also acute wound models (i.e burn wounds or incisional wound and chronic wound models (such as venous leg ulcers, diabetic foot ulcer, pressure ulcers or bedsore in laboratory animals are presented. This summary can be considered as a preliminary step to facilitate designing of more targeted and applied research in this area.

  4. Animal models of human colorectal cancer: Current status, uses and limitations.

    Science.gov (United States)

    Mittal, Vijay K; Bhullar, Jasneet Singh; Jayant, Kumar

    2015-11-07

    To make orthotopic colon cancer murine models a more clearly understood subject. The orthotopic tumor models have been found to be more relevant in replicating the human disease process as compared to heterotopic models, many techniques for making orthotopic colorectal murine models have been reported. We evaluated the current literature for various reported orthotopic colon cancer models to understand their techniques, advantages and limitations. An extensive literature review was performed by searching the National Library of Medicine Database (PubMed) using MeSH terms animal model; colon cancer; orthotopic model; murine model. Twenty studies related to colon cancer orthotopic xenograft model were evaluated in detail and discussed here. The detailed analysis of all relevant reports on orthotopic model showed tumor take rate between 42%-100%. While models using the enema technique and minimally invasive technique have reported development of tumor from mucosa with tumor take rate between 87%-100% with metastasis in 76%-90%. Over the years, the increased understanding of the murine models of human colon cancer has resulted in the development of various models. Each reported model has some limitations. These latest models have opened up new doors for continuing cancer research for not only understanding the colon cancer pathogenesis but also aid in the development of newer chemotherapeutic drugs as they mimic the human disease closely.

  5. [Construction and improvement of animal models with different positional osseous metastasis of prostate cancer in vivo].

    Science.gov (United States)

    Bi, Y X; Xiao, M H; Zhang, N N; Li, X Y; Mao, X P; Zhang, K; Zhang, Z R; Zhao, L Y

    2017-08-18

    To provide an important tool for the study of diagnose and treatment of prostate cancer (PCa) osseous metastasis and change of bone stress force on prostate cancer (PCa) osseous metastasis and a platform, which is more congruous to clinical process, for prevention and cure of neoplastic bone metastases, and to carry out the construction and improvement of animal models of PCa with different positional osseous metastasis in vivo. Different gradient concentrations of RM-1 cells were inoculated into the cavity of left femoral bone or lumbar vertebra of mice (C57BL/6) respectively. The change of mouse activity, tumor formation, tumor size and survival time were observed respectively. And the femur tissue and spinal tissue were obtained from the mice after death. The gray value of iconography were measured by imageological examination of femur tissue, and the final histopathological examination were taken to determine the tumor type in both femur and spinal tissue. The tumor growth could be touched at the puncture site in all the mice after inoculated for 7 days. There were no obvious differences in the time of tumorigenesis, the rate of tumor growth and tumor size among the mice in the same group (P>0.05). As the result, the construction femoral bone and lumbar vertebra metastatic models of PCa had been confirmed by iconography and pathology detection. At the same time, the survival time of the mice inoculated with low concentrations of PCa cells was obviously longer than that of high concentrations of PCa cells ( at least 2 weeks longer). The animal models with different positional osseous metastasis (limbs and axial skeleton) of PCa using the same PCa cells (RM-1) had been first constructed successfully in our study. At the same time, a high success rate of construction of PCa animal model with bone metastasis was obtained by femoral bone marrow cavity injection of PCa cells. The rate of tumor growth was rapid, animal survival time was appropriate, and the PCa animal

  6. Dynamical analysis of fractional order model of immunogenic tumors

    Directory of Open Access Journals (Sweden)

    Sadia Arshad

    2016-07-01

    Full Text Available In this article, we examine the fractional order model of the cytotoxic T lymphocyte response to a growing tumor cell population. We investigate the long-term behavior of tumor growth and explore the conditions of tumor elimination analytically. We establish the conditions for the tumor-free equilibrium and tumor-infection equilibrium to be asymptotically stable and provide the expression of the basic reproduction number. Existence of physical significant tumor-infection equilibrium points is investigated analytically. We show that tumor growth rate, source rate of immune cells, and death rate of immune cells play vital role in tumor dynamics and system undergoes saddle-node and transcritical bifurcation based on these parameters. Furthermore, the effect of cancer treatment is discussed by varying the values of relevant parameters. Numerical simulations are presented to illustrate the analytical results.

  7. Selenium prevents tumor development in a rat model for chemical carcinogenesis

    DEFF Research Database (Denmark)

    Bjorkhem-Bergman, L.; Torndal, U. B.; Eken, S.

    2005-01-01

    for chemically induced hepatocarcinogenesis, the resistant hepatocyte model. Selenite in supra-nutritional but subtoxic doses (1 and 5 p.p.m.) was administrated to the animals through the drinking water. Such supplementation during the initiation phase did not have a tumor preventive effect. However, selenite...

  8. Searching for better animal models of BPD: a perspective.

    Science.gov (United States)

    Ambalavanan, Namasivayam; Morty, Rory E

    2016-11-01

    There have been many efforts to develop good animal models of bronchopulmonary dysplasia (BPD) to better understand the pathophysiology and mechanisms underlying development of BPD as well as to test potential strategies for its prevention and treatment. This Perspectives summarizes the features of common animal models of BPD and the strengths and limitations of such models. Potential optimal approaches to development of animal models are indicated, with the underlying concepts that require emphasis. Copyright © 2016 the American Physiological Society.

  9. Investigation of independence in inter-animal tumor-type occurrences within the NTP rodent-bioassay database

    Energy Technology Data Exchange (ETDEWEB)

    Bogen, K.T. [Lawrence Livermore National Lab., CA (United States); Seilkop, S. [Analytical Sciences, Inc., Durham, NC (United States)

    1993-05-01

    Statistically significant elevation in tumor incidence at multiple histologically distinct sites is occasionally observed among rodent bioassays of chemically induced carcinogenesis. If such data are to be relied on (as they have, e.g., by the US EPA) for quantitative cancer potency assessment, their proper analysis requires a knowledge of the extent to which multiple tumor-type occurrences are independent or uncorrelated within individual bioassay animals. Although difficult to assess in a statistically rigorous fashion, a few significant associations among tumor-type occurrences in rodent bioassays have been reported. However, no comprehensive studies of animal-specific tumor-type occurrences at death or sacrifice have been conducted using the extensive set of available NTP rodent-bioassay data, on which most cancer-potency assessment for environmental chemicals is currently based. This report presents the results of such an analysis conducted on behalf of the National Research Council`s Committee on Risk Assessment for Hazardous Air Pollutants. Tumor-type associations among individual animals were examined for {approximately}2500 to 3000 control and {approximately}200 to 600 treated animals using pathology data from 62 B6C3F1 mouse studies and 61 F/344N rat studies obtained from a readily available subset of the NTP carcinogenesis bioassay database. No evidence was found for any large correlation in either the onset probability or the prevalence-at-death or sacrifice of any tumor-type pair investigated in control and treated rats and niece, although a few of the small correlations present were statistically significant. Tumor-type occurrences were in most cases nearly independent, and departures from independence, where they did occur, were small. This finding is qualified in that tumor-type onset correlations were measured only indirectly, given the limited nature of the data analyzed.

  10. Modeling individual animal histories with multistate capture–recapture models

    Science.gov (United States)

    Lebreton, Jean-Dominique; Nichols, James D.; Barker, Richard J.; Pradel, Roger; Spendelow, Jeffrey A.

    2009-01-01

    Many fields of science begin with a phase of exploration and description, followed by investigations of the processes that account for observed patterns. The science of ecology is no exception, and recent decades have seen a focus on understanding key processes underlying the dynamics of ecological systems. In population ecology, emphasis has shifted from the state variable of population size to the demographic processes responsible for changes in this state variable: birth, death, immigration, and emigration. In evolutionary ecology, some of these same demographic processes, rates of birth and death, are also the determinants of fitness. In animal population ecology, the estimation of state variables and their associated vital rates is especially problematic because of the difficulties in sampling such populations and detecting individual animals. Indeed, early capture–recapture models were developed for the purpose of estimating population size, given the reality that all animals are not caught or detected at any sampling occasion. More recently, capture–recapture models for open populations were developed to draw inferences about survival in the face of these same sampling problems. The focus of this paper is on multi‐state mark–recapture models (MSMR), which first appeared in the 1970s but have undergone substantial development in the last 15 years. These models were developed to deal explicitly with biological variation, in that animals in different “states” (classes defined by location, physiology, behavior, reproductive status, etc.) may have different probabilities of survival and detection. Animal transitions between states are also stochastic and themselves of interest. These general models have proven to be extremely useful and provide a way of thinking about a remarkably wide range of important ecological processes. These methods are now at a stage of refinement and sophistication where they can readily be used by biologists to tackle a wide

  11. Canine parvovirus NS1 protein exhibits anti-tumor activity in a mouse mammary tumor model.

    Science.gov (United States)

    Gupta, Shishir Kumar; Yadav, Pavan Kumar; Gandham, Ravi Kumar; Sahoo, A P; Harish, D R; Singh, Arvind Kumar; Tiwari, A K

    2016-02-02

    Many viral proteins have the ability to kill tumor cells specifically without harming the normal cells. These proteins, on ectopic expression, cause lysis or induction of apoptosis in the target tumor cells. Parvovirus NS1 is one of such proteins, which is known to kill high proliferating tumor cells. In the present study, we assessed the apoptosis inducing ability of canine parvovirus type 2 NS1 protein (CPV2.NS1) in vitro in 4T1 cells, and found it to cause significant cell death due to induction of apoptosis through intrinsic or mitochondrial pathway. Further, we also evaluated the oncolytic activity of CPV2.NS1 protein in a mouse mammary tumor model. The results suggested that CPV2.NS1 was able to inhibit the growth of 4T1 induced mouse mammary tumor as indicated by significantly reduced tumor volume, mitotic, AgNOR and PCNA indices. Further, inhibition of tumor growth was found to be because of induction of apoptosis in the tumor cells, which was evident by a significant increase in the number of TUNEL positive cells. Further, CPV2.NS1 was also able to stimulate the immune cells against the tumor antigens as indicated by the increased CD4+ and CD8+ counts in the blood of CVP2.NS1 treated mice. Further optimization of the delivery of NS1 protein and use of an adjuvant may further enhance its anti-tumor activity. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Computational modeling of brain tumors: discrete, continuum or hybrid?

    Science.gov (United States)

    Wang, Zhihui; Deisboeck, Thomas S.

    In spite of all efforts, patients diagnosed with highly malignant brain tumors (gliomas), continue to face a grim prognosis. Achieving significant therapeutic advances will also require a more detailed quantitative understanding of the dynamic interactions among tumor cells, and between these cells and their biological microenvironment. Data-driven computational brain tumor models have the potential to provide experimental tumor biologists with such quantitative and cost-efficient tools to generate and test hypotheses on tumor progression, and to infer fundamental operating principles governing bidirectional signal propagation in multicellular cancer systems. This review highlights the modeling objectives of and challenges with developing such in silico brain tumor models by outlining two distinct computational approaches: discrete and continuum, each with representative examples. Future directions of this integrative computational neuro-oncology field, such as hybrid multiscale multiresolution modeling are discussed.

  13. Sensitivity of MRI tumor biomarkers to VEGFR inhibitor therapy in an orthotopic mouse glioma model.

    Directory of Open Access Journals (Sweden)

    Christian T Farrar

    Full Text Available MRI biomarkers of tumor edema, vascular permeability, blood volume, and average vessel caliber are increasingly being employed to assess the efficacy of tumor therapies. However, the dependence of these biomarkers on a number of physiological factors can compromise their sensitivity and complicate the assessment of therapeutic efficacy. Here we examine the response of these MRI tumor biomarkers to cediranib, a potent vascular endothelial growth factor receptor (VEGFR inhibitor, in an orthotopic mouse glioma model. A significant increase in the tumor volume and relative vessel caliber index (rVCI and a slight decrease in the water apparent diffusion coefficient (ADC were observed for both control and cediranib treated animals. This contrasts with a clinical study that observed a significant decrease in tumor rVCI, ADC and volume with cediranib therapy. While the lack of a difference between control and cediranib treated animals in these biomarker responses might suggest that cediranib has no therapeutic benefit, cediranib treated mice had a significantly increased survival. The increased survival benefit of cediranib treated animals is consistent with the significant decrease observed for cediranib treated animals in the relative cerebral blood volume (rCBV, relative microvascular blood volume (rMBV, transverse relaxation time (T2, blood vessel permeability (K(trans, and extravascular-extracellular space (ν(e. The differential response of pre-clinical and clinical tumors to cediranib therapy, along with the lack of a positive response for some biomarkers, indicates the importance of evaluating the whole spectrum of different tumor biomarkers to properly assess the therapeutic response and identify and interpret the therapy-induced changes in the tumor physiology.

  14. Digital creature creation: applied 3D modelling and animation for Australian animal visualization

    OpenAIRE

    Ung, Chandara

    2017-01-01

    This exegesis focuses on the investigative and studio research informing the digital construction of a diverse selection of Australian animals. A series of case studies of digital creature construction - the Jackie Dragon, Jabiru, Bandicoot, Eel, Blue Ringed Octopus and Fiddler Crab - will be outlined along with the key creation study of the Groper. Through investigating how visual research can inform the creation of 3D modelled and animated animal subjects and tracing their development proce...

  15. A tumor cord model for Doxorubicin delivery and dose optimization in solid tumors

    Directory of Open Access Journals (Sweden)

    Eikenberry Steffen

    2009-08-01

    Full Text Available Abstract Background Doxorubicin is a common anticancer agent used in the treatment of a number of neoplasms, with the lifetime dose limited due to the potential for cardiotoxocity. This has motivated efforts to develop optimal dosage regimes that maximize anti-tumor activity while minimizing cardiac toxicity, which is correlated with peak plasma concentration. Doxorubicin is characterized by poor penetration from tumoral vessels into the tumor mass, due to the highly irregular tumor vasculature. I model the delivery of a soluble drug from the vasculature to a solid tumor using a tumor cord model and examine the penetration of doxorubicin under different dosage regimes and tumor microenvironments. Methods A coupled ODE-PDE model is employed where drug is transported from the vasculature into a tumor cord domain according to the principle of solute transport. Within the tumor cord, extracellular drug diffuses and saturable pharmacokinetics govern uptake and efflux by cancer cells. Cancer cell death is also determined as a function of peak intracellular drug concentration. Results The model predicts that transport to the tumor cord from the vasculature is dominated by diffusive transport of free drug during the initial plasma drug distribution phase. I characterize the effect of all parameters describing the tumor microenvironment on drug delivery, and large intercapillary distance is predicted to be a major barrier to drug delivery. Comparing continuous drug infusion with bolus injection shows that the optimum infusion time depends upon the drug dose, with bolus injection best for low-dose therapy but short infusions better for high doses. Simulations of multiple treatments suggest that additional treatments have similar efficacy in terms of cell mortality, but drug penetration is limited. Moreover, fractionating a single large dose into several smaller doses slightly improves anti-tumor efficacy. Conclusion Drug infusion time has a significant

  16. Sodium MRI of glioma in animal models at ultrahigh magnetic fields.

    Science.gov (United States)

    Schepkin, Victor D

    2016-02-01

    High magnetic fields expand our capability to use sodium MRI for biomedical applications. The central goal of this review is devoted to the unique features of sodium MRI in tumor animal models, mainly in glioma, performed at 9.4 and 21.1 T. The ability of sodium MRI to monitor tumor response to therapy was evaluated. It is noteworthy that sodium MRI can detect glioma response to chemotherapy earlier than diffusion MRI. Especially attractive is the ability of sodium MRI to predict tumor therapeutic resistance before therapy. The non-invasive prediction of tumor chemo-resistance by sodium MRI presents a potential to individualize strategies for cancer treatment. Specifics of sodium MRI and technical aspects of imaging are also presented. Copyright © 2015 John Wiley & Sons, Ltd.

  17. The complete guide to blender graphics computer modeling and animation

    CERN Document Server

    Blain, John M

    2014-01-01

    Smoothly Leads Users into the Subject of Computer Graphics through the Blender GUIBlender, the free and open source 3D computer modeling and animation program, allows users to create and animate models and figures in scenes, compile feature movies, and interact with the models and create video games. Reflecting the latest version of Blender, The Complete Guide to Blender Graphics: Computer Modeling & Animation, 2nd Edition helps beginners learn the basics of computer animation using this versatile graphics program. This edition incorporates many new features of Blender, including developments

  18. Investigation into the cancer protective effect of flaxseed in Tg.NK (MMTV/c-neu) mice, a murine mammary tumor model

    DEFF Research Database (Denmark)

    Birkved, Franziska Kramer; Mortensen, Alicja; Penalvo, Jose L

    2011-01-01

    The aim of the present study was to investigate whether low flaxseed doses relevant to human dietary exposure can prevent mammary tumors in transgenic Tg.NK mice, a model of breast cancer. Animals were exposed to flaxseed through the diet at human relevant levels. Tumor-related parameters and tumor...

  19. Modelling Nanoparticle Diffusion into Cancer Tumors

    Science.gov (United States)

    Podduturi, Vishwa Priya; Derosa, Pedro

    2011-03-01

    Cancer is one of the major, potentially deadly diseases and has been for years. Non-specific delivery of the drug can damage healthy tissue seriously affecting in many cases the patient's living condition. Nanoparticles are being used for a targeted drug delivery thereby reducing the dose. In addition, metallic nanoparticles are being used in thermal treatment of cancer cells where nanoparticles help concentrate heat in the tumor and away from living tissue. We proposed a model that combines random walk with diffusion principles. The particle drift velocity is taken from the Hagen-Poiseuille equation and the velocity profile of the particle at the pores in the capillary wall is obtained using the Coventorware software. Pressure gradient and concentration gradient through the capillary wall are considered. Simulations are performed in Matlab using the Monte Carlo technique. Number of particles leaving the blood vessel through a pore is obtained as a function of blood pressure, the osmotic pressure, temperature, particle concentration, blood vessel radius, and pore size, and the relative effect of each of the parameters is discussed.

  20. Modeling and testing treated tumor growth using cubic smoothing splines.

    Science.gov (United States)

    Kong, Maiying; Yan, Jun

    2011-07-01

    Human tumor xenograft models are often used in preclinical study to evaluate the therapeutic efficacy of a certain compound or a combination of certain compounds. In a typical human tumor xenograft model, human carcinoma cells are implanted to subjects such as severe combined immunodeficient (SCID) mice. Treatment with test compounds is initiated after tumor nodule has appeared, and continued for a certain time period. Tumor volumes are measured over the duration of the experiment. It is well known that untreated tumor growth may follow certain patterns, which can be described by certain mathematical models. However, the growth patterns of the treated tumors with multiple treatment episodes are quite complex, and the usage of parametric models is limited. We propose using cubic smoothing splines to describe tumor growth for each treatment group and for each subject, respectively. The proposed smoothing splines are quite flexible in modeling different growth patterns. In addition, using this procedure, we can obtain tumor growth and growth rate over time for each treatment group and for each subject, and examine whether tumor growth follows certain growth pattern. To examine the overall treatment effect and group differences, the scaled chi-squared test statistics based on the fitted group-level growth curves are proposed. A case study is provided to illustrate the application of this method, and simulations are carried out to examine the performances of the scaled chi-squared tests. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Model construction of nursing service satisfaction in hospitalized tumor patients.

    Science.gov (United States)

    Chen, Yongyi; Liu, Jingshi; Xiao, Shuiyuan; Liu, Xiangyu; Tang, Xinhui; Zhou, Yujuan

    2014-01-01

    This study aims to construct a satisfaction model on nursing service in hospitalized tumor patients. Using questionnaires, data about hospitalized tumor patients' expectation, quality perception and satisfaction of hospital nursing service were obtained. A satisfaction model of nursing service in hospitalized tumor patients was established through empirical study and by structural equation method. This model was suitable for tumor specialized hospital, with reliability and validity. Patient satisfaction was significantly affected by quality perception and patient expectation. Patient satisfaction and patient loyalty was also affected by disease pressure. Hospital brand was positively correlated with patient satisfaction and patient loyalty, negatively correlated with patient complaint. Patient satisfaction was positively correlated with patient loyalty, patient complaints, and quality perception, and negatively correlated with disease pressure and patient expectation. The satisfaction model on nursing service in hospitalized tumor patients fits well. By this model, the quality of hospital nursing care may be improved.

  2. A dose- and time-controllable syngeneic animal model of breast cancer microcalcification.

    Science.gov (United States)

    Liu, Fangbing; Misra, Preeti; Lunsford, Elaine P; Vannah, Joanne T; Liu, Yuxia; Lenkinski, Robert E; Frangioni, John V

    2010-07-01

    The development of novel diagnostic agents for the detection of breast cancer microcalcifications requires a reliable animal model. Based on previous work from our group, we hypothesized that a single systemic injection of recombinant bone morphogenetic protein-2 (rBMP-2) could be used to create such a model. The cDNA encoding mature human BMP-2 was expressed in BL21(DE3) bacteria, purified to homogeneity, and refolded as a dimer. Bioactivity was confirmed using a C2C12 alkaline phosphatase assay. rBMP-2 was radiolabeled with (99m)Tc, and its biodistribution and clearance were quantified after both intravenous (IV) and intraperitoneal (IP) injection. Fischer 344 rats bearing syngeneic R3230 breast tumors received a single intraperitoneal injection of rBMP-2 at a specified dose. Tumor microcalcification was quantified over time using micro-single photon emission computed tomography (SPECT) and microcomputed tomography (CT). rBMP-2 could be expressed in E. coli at high levels, isolated at >95% purity, and refolded to a bioactive dimer. Beta-phase half-life was 30.5 min after IV administration and 47.6 min after IP administration. Renal excretion was the primary mode of clearance. A single IP injection of >or=50 microg rBMP-2 when tumors were not yet palpable resulted in dose-dependent microcalcification in 8 of 8 R3230 tumors. No calcification was found in control tumors or in normal tissues and organs of animals injected with rBMP-2. Tumor calcification increased progressively between weeks 2 and 4 post-rBMP-2 injection. A single IP injection of rBMP-2 in rats bearing a syngeneic breast cancer will produce dose-dependent and time-dependent microcalcifications. This animal model lays the foundation for the development of novel diagnostic radiotracers for breast cancer.

  3. Single and 30 fraction tumor control doses correlate in xenografted tumor models: implications for predictive assays

    International Nuclear Information System (INIS)

    Gerweck, Leo E.; Dubois, Willum; Baumann, Michael; Suit, Herman D.

    1995-01-01

    , the rank-order correlation coefficient between the single dose hypoxic versus fractionated dose TCD50s under hypoxic or aerobic conditions was 1.0. For all 5 tumors examined, a trend for rank correlation was observed between the single dose and the fractionated dose TCD50s performed under normal or clamp hypoxic conditions (r=0.7, p=0.16 in both cases). The linear correlation coefficients were 0.83, p=0.08 and 0.72, p=0.17, respectively. Failure to attain a rank correlation of 1.0 was due to one tumor exhibiting an insignificant fractionation effect. The rank correlation between the TCD50s for fractionated treatments under normal versus the extrapolated TCD50s under clamp hypoxic conditions was 1.00; the linear correlation coefficient was 0.97 (p=0.01). Conclusions: In the tumor models examined, factors controlling the single fraction tumor control dose, also impact the response to fractionated treatments. These results suggest that laboratory estimates of intrinsic radiosensitivity and tumor clonogen number at the onset of treatment, will be of use in predicting radiocurability for fractionated treatments, as has been observed for single dose treatments

  4. A novel xenograft model in zebrafish for high-resolution investigating dynamics of neovascularization in tumors.

    Directory of Open Access Journals (Sweden)

    Chengjian Zhao

    Full Text Available Tumor neovascularization is a highly complex process including multiple steps. Understanding this process, especially the initial stage, has been limited by the difficulties of real-time visualizing the neovascularization embedded in tumor tissues in living animal models. In the present study, we have established a xenograft model in zebrafish by implanting mammalian tumor cells into the perivitelline space of 48 hours old Tg(Flk1:EGFP transgenic zebrafish embryos. With this model, we dynamically visualized the process of tumor neovascularization, with unprecedented high-resolution, including new sprouts from the host vessels and the origination from VEGFR2(+ individual endothelial cells. Moreover, we quantified their contributions during the formation of vascular network in tumor. Real-time observations revealed that angiogenic sprouts in tumors preferred to connect each other to form endothelial loops, and more and more endothelial loops accumulated into the irregular and chaotic vascular network. The over-expression of VEGF165 in tumor cells significantly affected the vascularization in xenografts, not only the number and size of neo-vessels but the abnormalities of tumor vascular architecture. The specific inhibitor of VEGFR2, SU5416, significantly inhibited the vascularization and the growth of melanoma xenografts, but had little affects to normal vessels in zebrafish. Thus, this zebrafish/tumor xenograft model not only provides a unique window to investigate the earliest events of tumoral neoangiogenesis, but is sensitive to be used as an experimental platform to rapidly and visually evaluate functions of angiogenic-related genes. Finally, it also offers an efficient and cost-effective means for the rapid evaluation of anti-angiogenic chemicals.

  5. Animation of 3D Model of Human Head

    Directory of Open Access Journals (Sweden)

    V. Michalcin

    2007-04-01

    Full Text Available The paper deals with the new algorithm of animation of 3D model of the human head in combination with its global motion. The designed algorithm is very fast and with low calculation requirements, because it does not need the synthesis of the input videosequence for estimation of the animation parameters as well as the parameters of global motion. The used 3D model Candide generates different expressions using its animation units which are controlled by the animation parameters. These ones are estimated on the basis of optical flow without the need of extracting of the feature points in the frames of the input videosequence because they are given by the selected vertices of the animation units of the calibrated 3D model Candide. The established multiple iterations inside the designed animation algorithm of 3D model of the human head between two successive frames significantly improved its accuracy above all for the large motion.

  6. MODELING OF ANIMATED SIMULATIONS BY MAXIMA PROGRAM TOOLS

    Directory of Open Access Journals (Sweden)

    Nataliya O. Bugayets

    2015-06-01

    Full Text Available The article deals with the methodical features in training of computer simulation of systems and processes using animation. In the article the importance of visibility of educational material that combines sensory and thinking sides of cognition is noted. The concept of modeling and the process of building models has been revealed. Attention is paid to the development of skills that are essential for effective learning of animated simulation by visual aids. The graphical environment tools of the computer mathematics system Maxima for animated simulation are described. The examples of creation of models animated visual aids and their use for the development of research skills are presented.

  7. Heralding a new paradigm in 3D tumor modeling.

    Science.gov (United States)

    Fong, Eliza L S; Harrington, Daniel A; Farach-Carson, Mary C; Yu, Hanry

    2016-11-01

    Numerous studies to date have contributed to a paradigm shift in modeling cancer, moving from the traditional two-dimensional culture system to three-dimensional (3D) culture systems for cancer cell culture. This led to the inception of tumor engineering, which has undergone rapid advances over the years. In line with the recognition that tumors are not merely masses of proliferating cancer cells but rather, highly complex tissues consisting of a dynamic extracellular matrix together with stromal, immune and endothelial cells, significant efforts have been made to better recapitulate the tumor microenvironment in 3D. These approaches include the development of engineered matrices and co-cultures to replicate the complexity of tumor-stroma interactions in vitro. However, the tumor engineering and cancer biology fields have traditionally relied heavily on the use of cancer cell lines as a cell source in tumor modeling. While cancer cell lines have contributed to a wealth of knowledge in cancer biology, the use of this cell source is increasingly perceived as a major contributing factor to the dismal failure rate of oncology drugs in drug development. Backing this notion is the increasing evidence that tumors possess intrinsic heterogeneity, which predominantly homogeneous cancer cell lines poorly reflect. Tumor heterogeneity contributes to therapeutic resistance in patients. To overcome this limitation, cancer cell lines are beginning to be replaced by primary tumor cell sources, in the form of patient-derived xenografts and organoids cultures. Moving forward, we propose that further advances in tumor engineering would require that tumor heterogeneity (tumor variants) be taken into consideration together with tumor complexity (tumor-stroma interactions). In this review, we provide a comprehensive overview of what has been achieved in recapitulating tumor complexity, and discuss the importance of incorporating tumor heterogeneity into 3D in vitro tumor models. This

  8. Animal Models of Compulsive Eating Behavior

    OpenAIRE

    Matteo Di Segni; Enrico Patrono; Loris Patella; Stefano Puglisi-Allegra; Rossella Ventura

    2014-01-01

    Eating disorders are multifactorial conditions that can involve a combination of genetic, metabolic, environmental, and behavioral factors. Studies in humans and laboratory animals show that eating can also be regulated by factors unrelated to metabolic control. Several studies suggest a link between stress, access to highly palatable food, and eating disorders. Eating “comfort foods” in response to a negative emotional state, for example, suggests that some individuals overeat to self-medica...

  9. A mouse model of luciferase-transfected stromal cells of giant cell tumor of bone.

    Science.gov (United States)

    Lau, Carol P Y; Wong, Kwok Chuen; Huang, Lin; Li, Gang; Tsui, Stephen K W; Kumta, Shekhar Madhukar

    2015-11-01

    A major barrier towards the study of the effects of drugs on Giant Cell Tumor of Bone (GCT) has been the lack of an animal model. In this study, we created an animal model in which GCT stromal cells survived and functioned as proliferating neoplastic cells. A proliferative cell line of GCT stromal cells was used to create a stable and luciferase-transduced cell line, Luc-G33. The cell line was characterized and was found that there were no significant differences on cell proliferation rate and recruitment of monocytes when compared with the wild type GCT stromal cells. We delivered the Luc-G33 cells either subcutaneously on the back or to the tibiae of the nude mice. The presence of viable Luc-G33 cells was assessed using real-time live imaging by the IVIS 200 bioluminescent imaging (BLI) system. The tumor cells initially propagated and remained viable on site for 7 weeks in the subcutaneous tumor model. We also tested in vivo antitumor effects of Zoledronate (ZOL) and Geranylgeranyl transferase-I inhibitor (GGTI-298) alone or their combinations in Luc-G33-transplanted nude mice. ZOL alone at 400 µg/kg and the co-treatment of ZOL at 400 µg/kg and GGTI-298 at 1.16 mg/kg reduced tumor cell viability in the model. Furthermore, the anti-tumor effects by ZOL, GGTI-298 and the co-treatment in subcutaneous tumor model were also confirmed by immunohistochemical (IHC) staining. In conclusion, we established a nude mice model of GCT stromal cells which allows non-invasive, real-time assessments of tumor development and testing the in vivo effects of different adjuvants for treating GCT.

  10. A new survival model for hyperthermic intraperitoneal chemotherapy (HIPEC) in tumor-bearing rats in the treatment of peritoneal carcinomatosis

    International Nuclear Information System (INIS)

    Pelz, Joerg OW; Doerfer, Joerg; Hohenberger, Werner; Meyer, Thomas

    2005-01-01

    Cytoreduction followed by hyperthermic intraperitoneal chemotherapy (HIPEC) improves survival in patients with peritoneal carcinomatosis of colorectal origin. Animal models are important in the evaluation of new treatment modalities. The purpose of this study was to devise an experimental setting which can be routinely used for the investigation of HIPEC in peritoneal carcinomatosis. A new peritoneal perfusion system in tumor bearing rats were tested. For this purpose CC531 colon carcinoma cells were implanted intraperitoneally in Wag/Rija rats. After 10 days of tumor growth the animals were randomized into three groups of six animals each: group 1: control (n = 6), group 2: HIPEC with mitomycin C in a concentration of 15 mg/m 2 (n = 6), group III: mitomycin C i.p. as monotherapy in a concentration of 10 mg/m 2 (n = 6). After 10 days, total tumor weight and the extent of tumor spread, as classified by the modified Peritoneal Cancer Index (PCI), were assessed by autopsy of the animals. No postoperative deaths were observed. Conjunctivitis, lethargy and loss of appetite were the main side effects in the HIPEC group. No severe locoregional or systemic toxity was observed. All control animals developed massive tumor growth. Tumor load was significantly reduced in the treatment group and was lowest in group II. The combination of hyperthermia with MMC resulted in an increased tumoricidal effect in the rat model. The presented model provides an opportunity to study the mechanism and effect of hyperthermic intraperitoneal chemotherapy and new drugs for this treatment modality

  11. A model of tumor architecture and spatial interactions with tumor microenvironment in breast carcinoma

    Science.gov (United States)

    Ben Cheikh, Bassem; Bor-Angelier, Catherine; Racoceanu, Daniel

    2017-03-01

    Breast carcinomas are cancers that arise from the epithelial cells of the breast, which are the cells that line the lobules and the lactiferous ducts. Breast carcinoma is the most common type of breast cancer and can be divided into different subtypes based on architectural features and growth patterns, recognized during a histopathological examination. Tumor microenvironment (TME) is the cellular environment in which tumor cells develop. Being composed of various cell types having different biological roles, TME is recognized as playing an important role in the progression of the disease. The architectural heterogeneity in breast carcinomas and the spatial interactions with TME are, to date, not well understood. Developing a spatial model of tumor architecture and spatial interactions with TME can advance our understanding of tumor heterogeneity. Furthermore, generating histological synthetic datasets can contribute to validating, and comparing analytical methods that are used in digital pathology. In this work, we propose a modeling method that applies to different breast carcinoma subtypes and TME spatial distributions based on mathematical morphology. The model is based on a few morphological parameters that give access to a large spectrum of breast tumor architectures and are able to differentiate in-situ ductal carcinomas (DCIS) and histological subtypes of invasive carcinomas such as ductal (IDC) and lobular carcinoma (ILC). In addition, a part of the parameters of the model controls the spatial distribution of TME relative to the tumor. The validation of the model has been performed by comparing morphological features between real and simulated images.

  12. The Use of Animal Models in Behavioural Neuroscience Research

    NARCIS (Netherlands)

    Bovenkerk, B.; Kaldewaij, F.

    2015-01-01

    Animal models are used in experiments in the behavioural neurosciences that aim to contribute to the prevention and treatment of cognitive and affective disorders in human beings, such as anxiety and depression. Ironically, those animals that are likely to be the best models for psychopathology are

  13. The Use of Animal Models in Behavioural Neuroscience Research.

    NARCIS (Netherlands)

    Bovenkerk, Bernice; Kaldewaij, Frederike

    2015-01-01

    Animal models are used in experiments in the behavioural neurosciences that aim to contribute to the prevention and treatment of cognitive and affective disorders in human beings, such as anxiety and depression. Ironically, those animals that are likely to be the best models for psychopathology are

  14. Stress and adaptation : Toward ecologically relevant animal models

    NARCIS (Netherlands)

    Koolhaas, Jaap M.; Boer, Sietse F. de; Buwalda, Bauke

    Animal models have contributed considerably to the current understanding of mechanisms underlying the role of stress in health and disease. Despite the progress made already, much more can be made by more carefully exploiting animals' and humans' shared biology, using ecologically relevant models.

  15. Aspects of animal models for major neuropsychiatric disorders

    Directory of Open Access Journals (Sweden)

    Lefter Radu

    2014-01-01

    Full Text Available We will review the main animal models for the major neuropsychiatric disorders, focusing on schizophrenia, Alzheimer’s disease, Parkinson’s disease, depression, anxiety and autism. Although these mental disorders are specifically human pathologies and therefore impossible to perfectly replicate in animals, the use of experimental animals is based on the physiological and anatomical similarities between humans and animals such as the rat, and mouse, and on the fact that 99% of human and murine genomes are shared. Pathological conditions in animals can be assessed by manipulating the metabolism of neurotransmitters, through various behavioral tests, and by determining biochemical parameters that can serve as important markers of disorders.

  16. Epidemiological Study of Mammary Tumors in Female Dogs Diagnosed during the Period 2002-2012: A Growing Animal Health Problem.

    Directory of Open Access Journals (Sweden)

    Yaritza Salas

    Full Text Available Epidemiological studies enable us to analyze disease behavior, define risk factors and establish fundamental prognostic criteria, with the purpose of studying different types of diseases. The aim of this study was to determine the epidemiological characteristics of canine mammary tumors diagnosed during the period 2002-2012. The study was based on a retrospective study consisting of 1,917 biopsies of intact dogs that presented mammary gland lesions. Biopsies were sent to the Department of Pathology FMVZ-UNAM diagnostic service. The annual incidence of mammary tumors was 16.8%: 47.7% (benign and 47.5% (malignant. The highest number of cases was epithelial, followed by mixed tumors. The most commonly diagnosed tumors were tubular adenoma, papillary adenoma, tubular carcinoma, papillary carcinoma, solid carcinoma, complex carcinoma and carcinosarcoma. Pure breeds accounted for 80% of submissions, and the Poodle, Cocker Spaniel and German Shepherd were consistently affected. Adult female dogs (9 to 12 years old were most frequently involved, followed by 5- to 8-year-old females. Some association between breeds with histological types of malignant tumors was observed, but no association was found between breeds and BN. Mammary tumors in intact dogs had a high incidence. Benign and malignant tumors had similar frequencies, with an increase in malignant tumors in the past four years of the study. Epithelial tumors were more common, and the most affected were old adult females, purebreds and small-sized dogs. Mammary tumors in dogs are an important animal health problem that needs to be solved by improving veterinary oncology services in Mexico.

  17. Formal models in animal-metacognition research: the problem of interpreting animals' behavior.

    Science.gov (United States)

    Smith, J David; Zakrzewski, Alexandria C; Church, Barbara A

    2016-10-01

    Ongoing research explores whether animals have precursors to metacognition-that is, the capacity to monitor mental states or cognitive processes. Comparative psychologists have tested apes, monkeys, rats, pigeons, and a dolphin using perceptual, memory, foraging, and information-seeking paradigms. The consensus is that some species have a functional analog to human metacognition. Recently, though, associative modelers have used formal-mathematical models hoping to describe animals' "metacognitive" performances in associative-behaviorist ways. We evaluate these attempts to reify formal models as proof of particular explanations of animal cognition. These attempts misunderstand the content and proper application of models. They embody mistakes of scientific reasoning. They blur fundamental distinctions in understanding animal cognition. They impede theoretical development. In contrast, an energetic empirical enterprise is achieving strong success in describing the psychology underlying animals' metacognitive performances. We argue that this careful empirical work is the clear path to useful theoretical development. The issues raised here about formal modeling-in the domain of animal metacognition-potentially extend to biobehavioral research more broadly.

  18. A Big Bang model of human colorectal tumor growth.

    Science.gov (United States)

    Sottoriva, Andrea; Kang, Haeyoun; Ma, Zhicheng; Graham, Trevor A; Salomon, Matthew P; Zhao, Junsong; Marjoram, Paul; Siegmund, Kimberly; Press, Michael F; Shibata, Darryl; Curtis, Christina

    2015-03-01

    What happens in early, still undetectable human malignancies is unknown because direct observations are impractical. Here we present and validate a 'Big Bang' model, whereby tumors grow predominantly as a single expansion producing numerous intermixed subclones that are not subject to stringent selection and where both public (clonal) and most detectable private (subclonal) alterations arise early during growth. Genomic profiling of 349 individual glands from 15 colorectal tumors showed an absence of selective sweeps, uniformly high intratumoral heterogeneity (ITH) and subclone mixing in distant regions, as postulated by our model. We also verified the prediction that most detectable ITH originates from early private alterations and not from later clonal expansions, thus exposing the profile of the primordial tumor. Moreover, some tumors appear 'born to be bad', with subclone mixing indicative of early malignant potential. This new model provides a quantitative framework to interpret tumor growth dynamics and the origins of ITH, with important clinical implications.

  19. Experimental Animal Models of Pancreatic Carcinogenesis for Prevention Studies and Their Relevance to Human Disease

    OpenAIRE

    Takahashi, Mami; Hori, Mika; Mutoh, Michihiro; Wakabayashi, Keiji; Nakagama, Hitoshi

    2011-01-01

    Pancreatic cancer is difficult to cure, so its prevention is very important. For this purpose, animal model studies are necessary to develop effective methods. Injection of N-nitrosobis(2-oxopropyl)amine (BOP) into Syrian golden hamsters is known to induce pancreatic ductal adenocarcinomas, the histology of which is similar to human tumors. Moreover, K-ras activation by point mutations and p16 inactivation by aberrant methylation of 5’ CpG islands or by homozygous deletions have been frequent...

  20. Animal models for microbicide safety and efficacy testing.

    Science.gov (United States)

    Veazey, Ronald S

    2013-07-01

    Early studies have cast doubt on the utility of animal models for predicting success or failure of HIV-prevention strategies, but results of multiple human phase 3 microbicide trials, and interrogations into the discrepancies between human and animal model trials, indicate that animal models were, and are, predictive of safety and efficacy of microbicide candidates. Recent studies have shown that topically applied vaginal gels, and oral prophylaxis using single or combination antiretrovirals are indeed effective in preventing sexual HIV transmission in humans, and all of these successes were predicted in animal models. Further, prior discrepancies between animal and human results are finally being deciphered as inadequacies in study design in the model, or quite often, noncompliance in human trials, the latter being increasingly recognized as a major problem in human microbicide trials. Successful microbicide studies in humans have validated results in animal models, and several ongoing studies are further investigating questions of tissue distribution, duration of efficacy, and continued safety with repeated application of these, and other promising microbicide candidates in both murine and nonhuman primate models. Now that we finally have positive correlations with prevention strategies and protection from HIV transmission, we can retrospectively validate animal models for their ability to predict these results, and more importantly, prospectively use these models to select and advance even safer, more effective, and importantly, more durable microbicide candidates into human trials.

  1. Numerical modeling of fluid flow in solid tumors.

    Directory of Open Access Journals (Sweden)

    M Soltani

    Full Text Available A mathematical model of interstitial fluid flow is developed, based on the application of the governing equations for fluid flow, i.e., the conservation laws for mass and momentum, to physiological systems containing solid tumors. The discretized form of the governing equations, with appropriate boundary conditions, is developed for a predefined tumor geometry. The interstitial fluid pressure and velocity are calculated using a numerical method, element based finite volume. Simulations of interstitial fluid transport in a homogeneous solid tumor demonstrate that, in a uniformly perfused tumor, i.e., one with no necrotic region, because of the interstitial pressure distribution, the distribution of drug particles is non-uniform. Pressure distribution for different values of necrotic radii is examined and two new parameters, the critical tumor radius and critical necrotic radius, are defined. Simulation results show that: 1 tumor radii have a critical size. Below this size, the maximum interstitial fluid pressure is less than what is generally considered to be effective pressure (a parameter determined by vascular pressure, plasma osmotic pressure, and interstitial osmotic pressure. Above this size, the maximum interstitial fluid pressure is equal to effective pressure. As a consequence, drugs transport to the center of smaller tumors is much easier than transport to the center of a tumor whose radius is greater than the critical tumor radius; 2 there is a critical necrotic radius, below which the interstitial fluid pressure at the tumor center is at its maximum value. If the tumor radius is greater than the critical tumor radius, this maximum pressure is equal to effective pressure. Above this critical necrotic radius, the interstitial fluid pressure at the tumor center is below effective pressure. In specific ranges of these critical sizes, drug amount and therefore therapeutic effects are higher because the opposing force, interstitial fluid

  2. Mathematical models of behavior of individual animals.

    Science.gov (United States)

    Tsibulsky, Vladimir L; Norman, Andrew B

    2007-01-01

    This review is focused on mathematical modeling of behaviors of a whole organism with special emphasis on models with a clearly scientific approach to the problem that helps to understand the mechanisms underlying behavior. The aim is to provide an overview of old and contemporary mathematical models without complex mathematical details. Only deterministic and stochastic, but not statistical models are reviewed. All mathematical models of behavior can be divided into two main classes. First, models that are based on the principle of teleological determinism assume that subjects choose the behavior that will lead them to a better payoff in the future. Examples are game theories and operant behavior models both of which are based on the matching law. The second class of models are based on the principle of causal determinism, which assume that subjects do not choose from a set of possibilities but rather are compelled to perform a predetermined behavior in response to specific stimuli. Examples are perception and discrimination models, drug effects models and individual-based population models. A brief overview of the utility of each mathematical model is provided for each section.

  3. Systematic reviews of animal models: methodology versus epistemology.

    Science.gov (United States)

    Greek, Ray; Menache, Andre

    2013-01-01

    Systematic reviews are currently favored methods of evaluating research in order to reach conclusions regarding medical practice. The need for such reviews is necessitated by the fact that no research is perfect and experts are prone to bias. By combining many studies that fulfill specific criteria, one hopes that the strengths can be multiplied and thus reliable conclusions attained. Potential flaws in this process include the assumptions that underlie the research under examination. If the assumptions, or axioms, upon which the research studies are based, are untenable either scientifically or logically, then the results must be highly suspect regardless of the otherwise high quality of the studies or the systematic reviews. We outline recent criticisms of animal-based research, namely that animal models are failing to predict human responses. It is this failure that is purportedly being corrected via systematic reviews. We then examine the assumption that animal models can predict human outcomes to perturbations such as disease or drugs, even under the best of circumstances. We examine the use of animal models in light of empirical evidence comparing human outcomes to those from animal models, complexity theory, and evolutionary biology. We conclude that even if legitimate criticisms of animal models were addressed, through standardization of protocols and systematic reviews, the animal model would still fail as a predictive modality for human response to drugs and disease. Therefore, systematic reviews and meta-analyses of animal-based research are poor tools for attempting to reach conclusions regarding human interventions.

  4. Intermittent hypoxia increases kidney tumor vascularization in a murine model of sleep apnea.

    Directory of Open Access Journals (Sweden)

    Antoni Vilaseca

    Full Text Available We investigate the effects of intermittent hypoxia (IH, a characteristic feature of obstructive sleep apnea (OSA, on renal cancer progression in an animal and cell model. An in vivo mouse model (Balb/c, n = 50 of kidney cancer was used to assess the effect of IH on tumor growth, metastatic capacity, angiogenesis and tumor immune response. An in vitro model tested the effect of IH on RENCA cells, macrophages and endothelial cells. Tumor growth, metastatic capacity, circulating vascular endothelial growth factor (VEGF and content of endothelial cells, tumor associated macrophages and their phenotype were assessed in the tumor. In vitro, VEGF cell expression was quantified.Although IH did not boost tumor growth, it significantly increased endothelial cells (p = 0.001 and circulating VEGF (p<0.001 in the in vivo model. Macrophages exposed to IH in vitro increased VEGF expression, whereas RENCA cells and endothelial cells did not. These findings are in keeping with previous clinical data suggesting that OSA has no effect on kidney cancer size and that the association observed between OSA and higher Fuhrman grade of renal cell carcinoma may be mediated though a proangiogenic process, with a key role of macrophages.

  5. Intermittent hypoxia increases kidney tumor vascularization in a murine model of sleep apnea.

    Science.gov (United States)

    Vilaseca, Antoni; Campillo, Noelia; Torres, Marta; Musquera, Mireia; Gozal, David; Montserrat, Josep M; Alcaraz, Antonio; Touijer, Karim A; Farré, Ramon; Almendros, Isaac

    2017-01-01

    We investigate the effects of intermittent hypoxia (IH), a characteristic feature of obstructive sleep apnea (OSA), on renal cancer progression in an animal and cell model. An in vivo mouse model (Balb/c, n = 50) of kidney cancer was used to assess the effect of IH on tumor growth, metastatic capacity, angiogenesis and tumor immune response. An in vitro model tested the effect of IH on RENCA cells, macrophages and endothelial cells. Tumor growth, metastatic capacity, circulating vascular endothelial growth factor (VEGF) and content of endothelial cells, tumor associated macrophages and their phenotype were assessed in the tumor. In vitro, VEGF cell expression was quantified.Although IH did not boost tumor growth, it significantly increased endothelial cells (p = 0.001) and circulating VEGF (p<0.001) in the in vivo model. Macrophages exposed to IH in vitro increased VEGF expression, whereas RENCA cells and endothelial cells did not. These findings are in keeping with previous clinical data suggesting that OSA has no effect on kidney cancer size and that the association observed between OSA and higher Fuhrman grade of renal cell carcinoma may be mediated though a proangiogenic process, with a key role of macrophages.

  6. Animal Models of Hemophilia and Related Bleeding Disorders

    Science.gov (United States)

    Lozier, Jay N.; Nichols, Timothy C.

    2013-01-01

    Animal models of hemophilia and related diseases are important for development of novel treatments and to understand the pathophysiology of bleeding disorders in humans. Testing in animals with the equivalent human disorder provides informed estimates of doses and measures of efficacy, which aids in design of human trials. Many models of hemophilia A, hemophilia B, and von Willebrand disease have been developed from animals with spontaneous mutations (hemophilia A dogs, rats, sheep; hemophilia B dogs; and von Willebrand disease pigs and dogs), or by targeted gene disruption in mice to create hemophilia A, B, or VWD models. Animal models have been used to generate new insights into the pathophysiology of each bleeding disorder and also to perform pre-clinical assessments of standard protein replacement therapies as well as novel gene transfer technology. Both the differences between species and differences in underlying causative mutations must be considered in choosing the best animal for a specific scientific study PMID:23956467

  7. Time series sightability modeling of animal populations.

    Directory of Open Access Journals (Sweden)

    Althea A ArchMiller

    Full Text Available Logistic regression models-or "sightability models"-fit to detection/non-detection data from marked individuals are often used to adjust for visibility bias in later detection-only surveys, with population abundance estimated using a modified Horvitz-Thompson (mHT estimator. More recently, a model-based alternative for analyzing combined detection/non-detection and detection-only data was developed. This approach seemed promising, since it resulted in similar estimates as the mHT when applied to data from moose (Alces alces surveys in Minnesota. More importantly, it provided a framework for developing flexible models for analyzing multiyear detection-only survey data in combination with detection/non-detection data. During initial attempts to extend the model-based approach to multiple years of detection-only data, we found that estimates of detection probabilities and population abundance were sensitive to the amount of detection-only data included in the combined (detection/non-detection and detection-only analysis. Subsequently, we developed a robust hierarchical modeling approach where sightability model parameters are informed only by the detection/non-detection data, and we used this approach to fit a fixed-effects model (FE model with year-specific parameters and a temporally-smoothed model (TS model that shares information across years via random effects and a temporal spline. The abundance estimates from the TS model were more precise, with decreased interannual variability relative to the FE model and mHT abundance estimates, illustrating the potential benefits from model-based approaches that allow information to be shared across years.

  8. Reviewing model application to support animal health decision making.

    Science.gov (United States)

    Singer, Alexander; Salman, Mo; Thulke, Hans-Hermann

    2011-04-01

    Animal health is of societal importance as it affects human welfare, and anthropogenic interests shape decision making to assure animal health. Scientific advice to support decision making is manifold. Modelling, as one piece of the scientific toolbox, is appreciated for its ability to describe and structure data, to give insight in complex processes and to predict future outcome. In this paper we study the application of scientific modelling to support practical animal health decisions. We reviewed the 35 animal health related scientific opinions adopted by the Animal Health and Animal Welfare Panel of the European Food Safety Authority (EFSA). Thirteen of these documents were based on the application of models. The review took two viewpoints, the decision maker's need and the modeller's approach. In the reviewed material three types of modelling questions were addressed by four specific model types. The correspondence between tasks and models underpinned the importance of the modelling question in triggering the modelling approach. End point quantifications were the dominating request from decision makers, implying that prediction of risk is a major need. However, due to knowledge gaps corresponding modelling studies often shed away from providing exact numbers. Instead, comparative scenario analyses were performed, furthering the understanding of the decision problem and effects of alternative management options. In conclusion, the most adequate scientific support for decision making - including available modelling capacity - might be expected if the required advice is clearly stated. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Time series sightability modeling of animal populations

    Science.gov (United States)

    ArchMiller, Althea A.; Dorazio, Robert; St. Clair, Katherine; Fieberg, John R.

    2018-01-01

    Logistic regression models—or “sightability models”—fit to detection/non-detection data from marked individuals are often used to adjust for visibility bias in later detection-only surveys, with population abundance estimated using a modified Horvitz-Thompson (mHT) estimator. More recently, a model-based alternative for analyzing combined detection/non-detection and detection-only data was developed. This approach seemed promising, since it resulted in similar estimates as the mHT when applied to data from moose (Alces alces) surveys in Minnesota. More importantly, it provided a framework for developing flexible models for analyzing multiyear detection-only survey data in combination with detection/non-detection data. During initial attempts to extend the model-based approach to multiple years of detection-only data, we found that estimates of detection probabilities and population abundance were sensitive to the amount of detection-only data included in the combined (detection/non-detection and detection-only) analysis. Subsequently, we developed a robust hierarchical modeling approach where sightability model parameters are informed only by the detection/non-detection data, and we used this approach to fit a fixed-effects model (FE model) with year-specific parameters and a temporally-smoothed model (TS model) that shares information across years via random effects and a temporal spline. The abundance estimates from the TS model were more precise, with decreased interannual variability relative to the FE model and mHT abundance estimates, illustrating the potential benefits from model-based approaches that allow information to be shared across years.

  10. Animal models for dengue vaccine development and testing.

    Science.gov (United States)

    Na, Woonsung; Yeom, Minjoo; Choi, Il-Kyu; Yook, Heejun; Song, Daesub

    2017-07-01

    Dengue fever is a tropical endemic disease; however, because of climate change, it may become a problem in South Korea in the near future. Research on vaccines for dengue fever and outbreak preparedness are currently insufficient. In addition, because there are no appropriate animal models, controversial results from vaccine efficacy assessments and clinical trials have been reported. Therefore, to study the mechanism of dengue fever and test the immunogenicity of vaccines, an appropriate animal model is urgently needed. In addition to mouse models, more suitable models using animals that can be humanized will need to be constructed. In this report, we look at the current status of model animal construction and discuss which models require further development.

  11. Animals

    International Nuclear Information System (INIS)

    Skuterud, L.; Strand, P.; Howard, B.J.

    1997-01-01

    The radionuclides of most concern with respect to contamination of animals after a nuclear accident are radioiodine, radiocaesium and radiostrontium (ICRP 30, 1979). Of the other significant anthropogenic radionuclides likely to be released in most accidents, only small proportions of that ingested will be absorbed in an animals gut, and the main animal products, milk and meat, will not normally be contaminated to a significant extent. Animal products will mostly be contaminated as a result of ingestion of contaminated feed and possibly, but to a much lesser extent, from inhalation (for radioiodine only). Direct external contamination of animals is of little or no consequence in human food production. Radioiodine and radiostrontium are important with respect to contamination of milk; radiocaesium contaminates both milk and meat. The physical and chemical form of a radionuclide can influence its absorption in the animal gut. For example, following the Chernobyl accident radiocaesium incorporated into vegetation by root uptake was more readily absorbed than that associated with the original deposit. The transfer of radiocaesium and radiostrontium to animals will be presented both as transfer coefficients and aggregated transfer coefficients. For most animal meat products, only radiocaesium is important as other radionuclides do not significantly contaminate muscle. Farm animal products are the most important foodstuff determining radiocaesium intake by the average consumer in the Nordic countries. The major potential source of radioiodine and radiostrontium to humans is milk and milk products. Of the different species, the smaller animals have the highest transfer of radiocaesium from fodder to meat and milk. (EG)

  12. Recent advances in animal model experimentation in autism research.

    Science.gov (United States)

    Tania, Mousumi; Khan, Md Asaduzzaman; Xia, Kun

    2014-10-01

    Autism, a lifelong neuro-developmental disorder is a uniquely human condition. Animal models are not the perfect tools for the full understanding of human development and behavior, but they can be an important place to start. This review focused on the recent updates of animal model research in autism. We have reviewed the publications over the last three decades, which are related to animal model study in autism. Animal models are important because they allow researchers to study the underlying neurobiology in a way that is not possible in humans. Improving the availability of better animal models will help the field to increase the development of medicines that can relieve disabling symptoms. Results from the therapeutic approaches are encouraging remarkably, since some behavioral alterations could be reversed even when treatment was performed on adult mice. Finding an animal model system with similar behavioral tendencies as humans is thus vital for understanding the brain mechanisms, supporting social motivation and attention, and the manner in which these mechanisms break down in autism. The ongoing studies should therefore increase the understanding of the biological alterations associated with autism as well as the development of knowledge-based treatments therapy for those struggling with autism. In this review, we have presented recent advances in research based on animal models of autism, raising hope for understanding the disease biology for potential therapeutic intervention to improve the quality of life of autism individuals.

  13. Animal models for human genetic diseases

    African Journals Online (AJOL)

    Sharif Sons

    to be the prime model of inherited human disease and share 99% of their ... disturbances (including anxiety and depression) ..... Leibovici M, Safieddine S, Petit C (2008). Mouse models for human hereditary deafness. Curr. Top. Dev. Biol. 84:385-429. Levi YF, Meiner Z, Canello T, Frid K, Kovacs GG, Budka H, Avrahami.

  14. Research progress on animal models of Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Wen DONG

    2015-08-01

    Full Text Available Alzheimer's disease (AD is a degenerative disease of the central nervous system, and its pathogenesis is complex. Animal models play an important role in study on pathogenesis and treatment of AD. This paper summarized methods of building models, observation on animal models and evaluation index in recent years, so as to provide related evidence for basic and clinical research in future. DOI: 10.3969/j.issn.1672-6731.2015.08.003

  15. Monitoring Prostate Tumor Growth in an Orthotopic Mouse Model Using Three-Dimensional Ultrasound Imaging Technique

    Directory of Open Access Journals (Sweden)

    Jie Ni

    2016-02-01

    Full Text Available Prostate cancer (CaP is the most commonly diagnosed and the second leading cause of death from cancer in males in USA. Prostate orthotopic mouse model has been widely used to study human CaP in preclinical settings. Measurement of changes in tumor size obtained from noninvasive diagnostic images is a standard method for monitoring responses to anticancer modalities. This article reports for the first time the usage of a three-dimensional (3D ultrasound system equipped with photoacoustic (PA imaging in monitoring longitudinal prostate tumor growth in a PC-3 orthotopic NODSCID mouse model (n = 8. Two-dimensional and 3D modes of ultrasound show great ability in accurately depicting the size and shape of prostate tumors. PA function on two-dimensional and 3D images showed average oxygen saturation and average hemoglobin concentration of the tumor. Results showed a good fit in representative exponential tumor growth curves (n = 3; r2 = 0.948, 0.955, and 0.953, respectively and a good correlation of tumor volume measurements performed in vivo with autopsy (n = 8, r = 0.95, P < .001. The application of 3D ultrasound imaging proved to be a useful imaging modality in monitoring tumor growth in an orthotopic mouse model, with advantages such as high contrast, uncomplicated protocols, economical equipment, and nonharmfulness to animals. PA mode also enabled display of blood oxygenation surrounding the tumor and tumor vasculature and angiogenesis, making 3D ultrasound imaging an ideal tool for preclinical cancer research.

  16. Animal Models and Antifungal Agents in Paracoccidioidomycosis: An Overview.

    Science.gov (United States)

    Goldani, Luciano Z; Wirth, Fernanda

    2017-08-01

    Paracoccidioides brasiliensis is the etiologic agent of paracoccidioidomycosis, the most prevalent systemic mycosis in Latin America. The morbidity and mortality associated with paracoccidioidomycosis necessitate our understanding of fungal pathogenesis and discovering of new agents to treat this infection. Animal models have contributed much to the knowledge of fungal infections and their corresponding therapeutic treatments. This is true for animal models of the primary fungal pathogens such as P. brasiliensis. This review describes the development, details and utility of animal models of paracoccidioidomycosis for studying and developing the current antifungal agents used for therapy of this fungal disease and novel agents with antifungal properties against P. brasiliensis.

  17. Lansoprazole as a rescue agent in chemoresistant tumors: a phase I/II study in companion animals with spontaneously occurring tumors

    Directory of Open Access Journals (Sweden)

    Spugnini Enrico P

    2011-12-01

    Full Text Available Abstract Background The treatment of human cancer has been seriously hampered for decades by resistance to chemotherapeutic drugs. Mechanisms underlying this resistance are far from being entirely known. A very efficient mechanism of tumor resistance to drugs is related to the modification of tumour microenvironment through changes in the extracellular and intracellular pH. The acidification of tumor microenvironment depends on proton pumps that actively pump protons outside the cells, mostly to avoid intracellular acidification. In fact, we have shown in pre-clinical settings as pre-treatment with proton-pumps inhibitors (PPI increase tumor cell and tumor responsiveness to chemotherapeutics. In this study pet with spontaneously occurring cancer proven refractory to conventional chemotherapy have been recruited in a compassionate study. Methods Thirty-four companion animals (27 dogs and 7 cats were treated adding to their chemotherapy protocols the pump inhibitor lansoprazole at high dose, as suggested by pre-clinical experiments. Their responses have been compared to those of seventeen pets (10 dogs and 7 cats whose owners did not pursue any other therapy than continuing the currently ongoing chemotherapy protocols. Results The drug was overall well tolerated, with only four dogs experiencing side effects due to gastric hypochlorhydria consisting with vomiting and or diarrhea. In terms of overall response twenty-three pets out of 34 had partial or complete responses (67.6% the remaining patients experienced no response or progressive disease however most owners reported improved quality of life in most of the non responders. On the other hand, only three animals in the control group (17% experienced short lived partial responses (1-3 months duration while all the others died of progressive disease within two months. Conclusions high dose proton pump inhibitors have been shown to induce reversal of tumor chemoresistance as well as improvement of

  18. Modeling the Effect of Tumor Size in Early Breast Cancer

    Science.gov (United States)

    Verschraegen, Claire; Vinh-Hung, Vincent; Cserni, Gábor; Gordon, Richard; Royce, Melanie E.; Vlastos, Georges; Tai, Patricia; Storme, Guy

    2005-01-01

    Summary Background Data: The purpose of this study was to determine the type of relationship between tumor size and mortality in early breast carcinoma. Methods: The data was abstracted from 83,686 cases registered in the Surveillance, Epidemiology, and End Results Program of women diagnosed with primary breast carcinoma between 1988 and 1997 presenting with a T1–T2 lesion and no metastasis in whom axillary node dissection was performed: 58,070 women were node-negative (N0) and 25,616 were node-positive (N+). End point was death from any cause. Tumor size was modeled as a continuous variable by proportional hazards using a generalized additive models procedure. Results: Functionally, a Gompertzian expression exp(-exp(-(size-15)/10)) provided a good fit to the effect of tumor size (in millimeters) on mortality, irrespective of nodal status. Quantitatively, for tumor size between 3 and 50 mm, the increase of crude cumulative death rate (number of observed deaths divided by the number of patients at risk) increased with size from 10% to 25% for N0 and from 20% to 40% for N+. Conclusions: The functional relationship of tumor size with mortality is concordant with current knowledge of tumor growth. However, its qualitative and quantitative independence of nodal status is in contradiction with the prevailing concept of sequential disease progression from primary tumor to regional nodes. This argues against the perception that nodal metastases are caused by the primary tumor. PMID:15650642

  19. Epidemiological models to support animal disease surveillance activities

    DEFF Research Database (Denmark)

    Willeberg, Preben; Paisley, Larry; Lind, Peter

    2011-01-01

    Epidemiological models have been used extensively as a tool in improving animal disease surveillance activities. A review of published papers identified three main groups of model applications: models for planning surveillance, models for evaluating the performance of surveillance systems...... and models for interpreting surveillance data as part of ongoing control or eradication programmes. Two Danish examples are outlined. The first illustrates how models were used in documenting country freedom from disease (trichinellosis) and the second demonstrates how models were of assistance in predicting...

  20. Animal models for periodontal regeneration and peri-implant responses.

    Science.gov (United States)

    Kantarci, Alpdogan; Hasturk, Hatice; Van Dyke, Thomas E

    2015-06-01

    Translation of experimental data to the clinical setting requires the safety and efficacy of such data to be confirmed in animal systems before application in humans. In dental research, the animal species used is dependent largely on the research question or on the disease model. Periodontal disease and, by analogy, peri-implant disease, are complex infections that result in a tissue-degrading inflammatory response. It is impossible to explore the complex pathogenesis of periodontitis or peri-implantitis using only reductionist in-vitro methods. Both the disease process and healing of the periodontal and peri-implant tissues can be studied in animals. Regeneration (after periodontal surgery), in response to various biologic materials with potential for tissue engineering, is a continuous process involving various types of tissue, including epithelia, connective tissues and alveolar bone. The same principles apply to peri-implant healing. Given the complexity of the biology, animal models are necessary and serve as the standard for successful translation of regenerative materials and dental implants to the clinical setting. Smaller species of animal are more convenient for disease-associated research, whereas larger animals are more appropriate for studies that target tissue healing as the anatomy of larger animals more closely resembles human dento-alveolar architecture. This review focuses on the animal models available for the study of regeneration in periodontal research and implantology; the advantages and disadvantages of each animal model; the interpretation of data acquired; and future perspectives of animal research, with a discussion of possible nonanimal alternatives. Power calculations in such studies are crucial in order to use a sample size that is large enough to generate statistically useful data, whilst, at the same time, small enough to prevent the unnecessary use of animals. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Mathematical Modeling of Branching Morphogenesis and Vascular Tumor Growth

    Science.gov (United States)

    Yan, Huaming

    Feedback regulation of cell lineages is known to play an important role in tissue size control, but the effect in tissue morphogenesis has yet to be explored. We first use a non-spatial model to show that a combination of positive and negative feedback on stem and/or progenitor cell self-renewal leads to bistable or bi-modal growth behaviors and ultrasensitivity to external growth cues. Next, a spatiotemporal model is used to demonstrate spatial patterns such as local budding and branching arise in this setting, and are not consequences of Turing-type instabilities. We next extend the model to a three-dimensional hybrid discrete-continuum model of tumor growth to study the effects of angiogenesis, tumor progression and cancer therapies. We account for the crosstalk between the vasculature and cancer stem cells (CSCs), and CSC transdifferentiation into vascular endothelial cells (gECs), as observed experimentally. The vasculature stabilizes tumor invasiveness but considerably enhances growth. A gEC network structure forms spontaneously within the hypoxic core, consistent with experimental findings. The model is then used to study cancer therapeutics. We demonstrate that traditional anti-angiogenic therapies decelerate tumor growth, but make the tumor highly invasive. Chemotherapies help to reduce tumor sizes, but cannot control the invasion. Anti-CSC therapies that promote differentiation or disturb the stem cell niche effectively reduce tumor invasiveness. However, gECs inherit mutations present in CSCs and are resistant to traditional therapies. We show that anti-gEC treatments block the support on CSCs by gECs, and reduce both tumor size and invasiveness. Our study suggests that therapies targeting the vasculature, CSCs and gECs, when combined, are highly synergistic and are capable of controlling both tumor size and shape.

  2. Application of Model Animals in the Study of Drug Toxicology

    Science.gov (United States)

    Song, Yagang; Miao, Mingsan

    2018-01-01

    Drug safety is a key factor in drug research and development, Drug toxicology test is the main method to evaluate the safety of drugs, The body condition of an animal has important implications for the results of the study, Previous toxicological studies of drugs were carried out in normal animals in the past, There is a great deviation from the clinical practice.The purpose of this study is to investigate the necessity of model animals as a substitute for normal animals for toxicological studies, It is expected to provide exact guidance for future drug safety evaluation.

  3. Animal models for testing anti-prion drugs.

    Science.gov (United States)

    Fernández-Borges, Natalia; Elezgarai, Saioa R; Eraña, Hasier; Castilla, Joaquín

    2013-01-01

    Prion diseases belong to a group of fatal infectious diseases with no effective therapies available. Throughout the last 35 years, less than 50 different drugs have been tested in different experimental animal models without hopeful results. An important limitation when searching for new drugs is the existence of appropriate models of the disease. The three different possible origins of prion diseases require the existence of different animal models for testing anti-prion compounds. Wild type, over-expressing transgenic mice and other more sophisticated animal models have been used to evaluate a diversity of compounds which some of them were previously tested in different in vitro experimental models. The complexity of prion diseases will require more pre-screening studies, reliable sporadic (or spontaneous) animal models and accurate chemical modifications of the selected compounds before having an effective therapy against human prion diseases. This review is intended to put on display the more relevant animal models that have been used in the search of new antiprion therapies and describe some possible procedures when handling chemical compounds presumed to have anti-prion activity prior to testing them in animal models.

  4. Modeling animal movements using stochastic differential equations

    Science.gov (United States)

    Haiganoush K. Preisler; Alan A. Ager; Bruce K. Johnson; John G. Kie

    2004-01-01

    We describe the use of bivariate stochastic differential equations (SDE) for modeling movements of 216 radiocollared female Rocky Mountain elk at the Starkey Experimental Forest and Range in northeastern Oregon. Spatially and temporally explicit vector fields were estimated using approximating difference equations and nonparametric regression techniques. Estimated...

  5. Modeling and Targeting MYC Genes in Childhood Brain Tumors

    Science.gov (United States)

    Hutter, Sonja; Bolin, Sara; Weishaupt, Holger; Swartling, Fredrik J.

    2017-01-01

    Brain tumors are the second most common group of childhood cancers, accounting for about 20%–25% of all pediatric tumors. Deregulated expression of the MYC family of transcription factors, particularly c-MYC and MYCN genes, has been found in many of these neoplasms, and their expression levels are often correlated with poor prognosis. Elevated c-MYC/MYCN initiates and drives tumorigenesis in many in vivo model systems of pediatric brain tumors. Therefore, inhibition of their oncogenic function is an attractive therapeutic target. In this review, we explore the roles of MYC oncoproteins and their molecular targets during the formation, maintenance, and recurrence of childhood brain tumors. We also briefly summarize recent progress in the development of therapeutic approaches for pharmacological inhibition of MYC activity in these tumors. PMID:28333115

  6. Animal models of substance abuse and addiction: implications for science, animal welfare, and society.

    Science.gov (United States)

    Lynch, Wendy J; Nicholson, Katherine L; Dance, Mario E; Morgan, Richard W; Foley, Patricia L

    2010-06-01

    Substance abuse and addiction are well recognized public health concerns, with 2 NIH institutes (the National Institute on Drug Abuse and the National Institute on Alcohol Abuse and Alcoholism) specifically targeting this societal problem. As such, this is an important area of research for which animal experiments play a critical role. This overview presents the importance of substance abuse and addiction in society; reviews the development and refinement of animal models that address crucial areas of biology, pathophysiology, clinical treatments, and drug screening for abuse liability; and discusses some of the unique veterinary, husbandry, and IACUC challenges associated with these models.

  7. Mathematical and Computational Modeling for Tumor Virotherapy with Mediated Immunity.

    Science.gov (United States)

    Timalsina, Asim; Tian, Jianjun Paul; Wang, Jin

    2017-08-01

    We propose a new mathematical modeling framework based on partial differential equations to study tumor virotherapy with mediated immunity. The model incorporates both innate and adaptive immune responses and represents the complex interaction among tumor cells, oncolytic viruses, and immune systems on a domain with a moving boundary. Using carefully designed computational methods, we conduct extensive numerical simulation to the model. The results allow us to examine tumor development under a wide range of settings and provide insight into several important aspects of the virotherapy, including the dependence of the efficacy on a few key parameters and the delay in the adaptive immunity. Our findings also suggest possible ways to improve the virotherapy for tumor treatment.

  8. Animals

    Energy Technology Data Exchange (ETDEWEB)

    Skuterud, L.; Strand, P. [Norwegian Radiation Protection Authority (Norway); Howard, B.J. [Inst. of Terrestrial Ecology (United Kingdom)

    1997-10-01

    The radionuclides of most concern with respect to contamination of animals after a nuclear accident are radioiodine, radiocaesium and radiostrontium (ICRP 30, 1979). Of the other significant anthropogenic radionuclides likely to be released in most accidents, only small proportions of that ingested will be absorbed in an animals gut, and the main animal products, milk and meat, will not normally be contaminated to a significant extent. Animal products will mostly be contaminated as a result of ingestion of contaminated feed and possibly, but to a much lesser extent, from inhalation (for radioiodine only). Direct external contamination of animals is of little or no consequence in human food production. Radioiodine and radiostrontium are important with respect to contamination of milk; radiocaesium contaminates both milk and meat. The physical and chemical form of a radionuclide can influence its absorption in the animal gut. For example, following the Chernobyl accident radiocaesium incorporated into vegetation by root uptake was more readily absorbed than that associated with the original deposit. The transfer of radiocaesium and radiostrontium to animals will be presented both as transfer coefficients and aggregated transfer coefficients. For most animal meat products, only radiocaesium is important as other radionuclides do not significantly contaminate muscle. Farm animal products are the most important foodstuff determining radiocaesium intake by the average consumer in the Nordic countries. The major potential source of radioiodine and radiostrontium to humans is milk and milk products. Of the different species, the smaller animals have the highest transfer of radiocaesium from fodder to meat and milk. (EG). 68 refs.

  9. Advances in Animal Models of Hepatitis B Virus Infection

    Directory of Open Access Journals (Sweden)

    Zhang Hang

    2015-12-01

    Full Text Available Hepatitis B virus (HBV infection seriously affects human health. Stable and reliable animal models of HBV infection bear significance in studying pathogenesis of this health condition and development of intervention measures. HBV exhibits high specificity for hosts, and chimpanzee is long used as sole animal model of HBV infection. However, use of chimpanzees is strictly constrained because of ethical reasons. Many methods were used to establish small-animal models of HBV infection. Tupaia is the only nonprimate animal that can be infected by HBV. Use of HBV-related duck hepatitis virus and marmot hepatitis virus infection model contributed to evaluation of mechanism of HBV replication and HBV treatment methods. In recent years, development of human–mouse chimeric model provided possibility of using common experimental animals to carry out HBV research. These models feature their own advantages and disadvantages and can be complementary in some ways. This study provides an overview of current and commonly used animal models of HBV infection.

  10. Animal models for evaluation of oral delivery of biopharmaceuticals

    DEFF Research Database (Denmark)

    Harloff-Helleberg, Stine; Nielsen, Line Hagner; Nielsen, Hanne Mørck

    2017-01-01

    of systems for oral delivery of biopharmaceuticals may result in new treatment modalities to increase the patient compliance and reduce product cost. In the preclinical development phase, use of experimental animal models is essential for evaluation of new formulation designs. In general, the limited oral...... bioavailability of biopharmaceuticals, of just a few percent, is expected, and therefore, the animal models and the experimental settings must be chosen with utmost care. More knowledge and focus on this topic is highly needed, despite experience from the numerous studies evaluating animal models for oral drug...... delivery of small molecule drugs. This review highlights and discusses pros and cons of the most currently used animal models and settings. Additionally, it also looks into the influence of anesthetics and sampling methods for evaluation of drug delivery systems for oral delivery of biopharmaceuticals...

  11. Albino mice as an animal model for infantile nystagmus syndrome

    NARCIS (Netherlands)

    D.L. Traber (Daniel); C.-C. Chen (Chien-Cheng); Y.-Y. Huang (Ying-Yu); M. Spoor (Monique); J. Roos (Jeanine); M.A. Frens (Maarten); D. Straumann (Dominik); C. Grimm (Christian)

    2012-01-01

    textabstractPURPOSE. Individuals with oculocutaneous albinism are predisposed to visual system abnormalities affecting the retina and retinofugal projections, which may lead to reduced visual acuity and Infantile Nystagmus Syndrome (INS). Due to absence of an established mammalian animal model,

  12. Instrumental and ethical aspects of experimental research with animal models

    Directory of Open Access Journals (Sweden)

    Mirian Watanabe

    2014-02-01

    Full Text Available Experimental animal models offer possibilities of physiology knowledge, pathogenesis of disease and action of drugs that are directly related to quality nursing care. This integrative review describes the current state of the instrumental and ethical aspects of experimental research with animal models, including the main recommendations of ethics committees that focus on animal welfare and raises questions about the impact of their findings in nursing care. Data show that, in Brazil, the progress in ethics for the use of animals for scientific purposes was consolidated with Law No. 11.794/2008 establishing ethical procedures, attending health, genetic and experimental parameters. The application of ethics in handling of animals for scientific and educational purposes and obtaining consistent and quality data brings unquestionable contributions to the nurse, as they offer subsidies to relate pathophysiological mechanisms and the clinical aspect on the patient.

  13. Biology of Obesity: Lessons from Animal Models of Obesity

    Directory of Open Access Journals (Sweden)

    Keizo Kanasaki

    2011-01-01

    problems, including diabetes, cardiovascular disease, respiratory failure, muscle weakness, and cancer. The precise molecular mechanisms by which obesity induces these health problems are not yet clear. To better understand the pathomechanisms of human disease, good animal models are essential. In this paper, we will analyze animal models of obesity and their use in the research of obesity-associated human health conditions and diseases such as diabetes, cancer, and obstructive sleep apnea syndrome.

  14. Computer Implementation of a New Therapeutic Model for GBM Tumor

    Directory of Open Access Journals (Sweden)

    Ali Jamali Nazari

    2014-01-01

    Full Text Available Modeling the tumor behavior in the host organ as function of time and radiation dose has been a major study in the previous decades. Here the effort in estimation of cancerous and normal cell proliferation and growth in glioblastoma multiform (GBM tumor is presented. This paper introduces a new mathematical model in the form of differential equation of tumor growth. The model contains dose delivery amount in the treatment scheme as an input term. It also can be utilized to optimize the treatment process in order to increase the patient survival period. Gene expression programming (GEP as a new concept is used for estimating this model. The LQ model has also been applied to GEP as an initial value, causing acceleration and improvement of the algorithm estimation. The model shows the number of the tumor and normal brain cells during the treatment process using the status of normal and cancerous cells in the initiation of treatment, the timing and amount of dose delivery to the patient, and a coefficient that describes the brain condition. A critical level is defined for normal cell when the patient’s death occurs. In the end the model has been verified by clinical data obtained from previous accepted formulae and some of our experimental resources. The proposed model helps to predict tumor growth during treatment process in which further treatment processes can be controlled.

  15. A fractional motion diffusion model for grading pediatric brain tumors.

    Science.gov (United States)

    Karaman, M Muge; Wang, He; Sui, Yi; Engelhard, Herbert H; Li, Yuhua; Zhou, Xiaohong Joe

    2016-01-01

    To demonstrate the feasibility of a novel fractional motion (FM) diffusion model for distinguishing low- versus high-grade pediatric brain tumors; and to investigate its possible advantage over apparent diffusion coefficient (ADC) and/or a previously reported continuous-time random-walk (CTRW) diffusion model. With approval from the institutional review board and written informed consents from the legal guardians of all participating patients, this study involved 70 children with histopathologically-proven brain tumors (30 low-grade and 40 high-grade). Multi- b -value diffusion images were acquired and analyzed using the FM, CTRW, and mono-exponential diffusion models. The FM parameters, D fm , φ , ψ (non-Gaussian diffusion statistical measures), and the CTRW parameters, D m , α , β (non-Gaussian temporal and spatial diffusion heterogeneity measures) were compared between the low- and high-grade tumor groups by using a Mann-Whitney-Wilcoxon U test. The performance of the FM model for differentiating between low- and high-grade tumors was evaluated and compared with that of the CTRW and the mono-exponential models using a receiver operating characteristic (ROC) analysis. The FM parameters were significantly lower ( p  CTRW model. Similar to the CTRW model, the FM model can improve differentiation between low- and high-grade pediatric brain tumors over ADC.

  16. Stop staring facial modeling and animation done right

    CERN Document Server

    Osipa, Jason

    2010-01-01

    The de facto official source on facial animation—now updated!. If you want to do character facial modeling and animation at the high levels achieved in today's films and games, Stop Staring: Facial Modeling and Animation Done Right, Third Edition , is for you. While thoroughly covering the basics such as squash and stretch, lip syncs, and much more, this new edition has been thoroughly updated to capture the very newest professional design techniques, as well as changes in software, including using Python to automate tasks.: Shows you how to create facial animation for movies, games, and more;

  17. Technical Note: How to use Winbugs to infer animal models

    DEFF Research Database (Denmark)

    Damgaard, Lars Holm

    2007-01-01

    This paper deals with Bayesian inferences of animal models using Gibbs sampling. First, we suggest a general and efficient method for updating additive genetic effects, in which the computational cost is independent of the pedigree depth and increases linearly only with the size of the pedigree. ...... having Student's t distributions. In conclusion, Winbugs can be used to make inferences in small-sized, quantitative, genetic data sets applying a wide range of animal models that are not yet standard in the animal breeding literature...

  18. Reflected stochastic differential equation models for constrained animal movement

    Science.gov (United States)

    Hanks, Ephraim M.; Johnson, Devin S.; Hooten, Mevin B.

    2017-01-01

    Movement for many animal species is constrained in space by barriers such as rivers, shorelines, or impassable cliffs. We develop an approach for modeling animal movement constrained in space by considering a class of constrained stochastic processes, reflected stochastic differential equations. Our approach generalizes existing methods for modeling unconstrained animal movement. We present methods for simulation and inference based on augmenting the constrained movement path with a latent unconstrained path and illustrate this augmentation with a simulation example and an analysis of telemetry data from a Steller sea lion (Eumatopias jubatus) in southeast Alaska.

  19. Proteomics in farm animals models of human diseases.

    Science.gov (United States)

    Ceciliani, Fabrizio; Restelli, Laura; Lecchi, Cristina

    2014-10-01

    The need to provide in vivo complex environments to understand human diseases strongly relies on the use of animal models, which traditionally include small rodents and rabbits. It is becoming increasingly evident that the few species utilised to date cannot be regarded as universal. There is a great need for new animal species that are naturally endowed with specific features relevant to human diseases. Farm animals, including pigs, cows, sheep and horses, represent a valid alternative to commonly utilised rodent models. There is an ample scope for the application of proteomic techniques in farm animals, and the establishment of several proteomic maps of plasma and tissue has clearly demonstrated that farm animals provide a disease environment that closely resembles that of human diseases. The present review offers a snapshot of how proteomic techniques have been applied to farm animals to improve their use as biomedical models. Focus will be on specific topics of biomedical research in which farm animal models have been characterised through the application of proteomic techniques. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Animal models of pancreatic cancer for drug research.

    Science.gov (United States)

    Kapischke, Matthias; Pries, Alexandra

    2008-10-01

    The operative and conservative results of therapy in pancreatic ductal adenocarcinoma remain appallingly poor. This underlines the demand for further research for effective anticancer drugs. The various animal models remain the essential method for the determination of efficacy of substances during preclinical phase. Unfortunately, most of these tested substances showed a good efficacy in pancreatic carcinoma in the animal model but were not confirmed during the clinical phase. The available literature in PubMed, Medline, Ovid and secondary literature was searched regarding the available animal models for drug testing against pancreatic cancer. The models were analyzed regarding their pros and cons in anticancer drug testing. The different modifications of the orthotopic model (especially in mice) seem at present to be the best model for anticancer testing in pancreatic carcinoma. The value of genetically engineered animal model (GEM) and syngeneic models is on debate. A good selection of the model concerning the questions supposed to be clarified may improve the comparability of the results of animal experiments compared to clinical trials.

  1. Effect of Irradiation on Tumor Microenvironment and Bone Marrow Cell Migration in a Preclinical Tumor Model

    Energy Technology Data Exchange (ETDEWEB)

    Kane, Jonathan L. [Department of Biological Sciences, Oakland University, Rochester, Michigan (United States); Department of Radiation Oncology, William Beaumont Health System, Royal Oak, Michigan (United States); Krueger, Sarah A.; Hanna, Alaa [Department of Radiation Oncology, William Beaumont Health System, Royal Oak, Michigan (United States); Raffel, Thomas R. [Department of Biological Sciences, Oakland University, Rochester, Michigan (United States); Wilson, George D. [Department of Radiation Oncology, William Beaumont Health System, Royal Oak, Michigan (United States); Madlambayan, Gerard J. [Department of Biological Sciences, Oakland University, Rochester, Michigan (United States); Marples, Brian, E-mail: Brian.Marples@beaumont.edu [Department of Radiation Oncology, William Beaumont Health System, Royal Oak, Michigan (United States)

    2016-09-01

    Purpose: To characterize the tumor microenvironment after standard radiation therapy (SRT) and pulsed radiation therapy (PRT) in Lewis lung carcinoma (LLC) allografts. Methods and Materials: Subcutaneous LLC tumors were established in C57BL/6 mice. Standard RT or PRT was given at 2 Gy/d for a total dose of 20 Gy using a 5 days on, 2 days off schedule to mimic clinical delivery. Radiation-induced tumor microenvironment changes were examined after treatment using flow cytometry and antibody-specific histopathology. Normal tissue effects were measured using noninvasive {sup 18}F-fluorodeoxyglucose positron emission tomography/computed tomography after naïve animals were given whole-lung irradiation to 40 Gy in 4 weeks using the same 2-Gy/d regimens. Results: Over the 2 weeks of therapy, PRT was more effective than SRT at reducing tumor growth rate (0.31 ± 0.02 mm{sup 3}/d and 0.55 ± 0.04 mm{sup 3}/d, respectively; P<.007). Histopathology showed a significant comparative reduction in the levels of Ki-67 (14.5% ± 3%), hypoxia (10% ± 3.5%), vascular endothelial growth factor (2.3% ± 1%), and stromal-derived factor-1α (2.5% ± 1.4%), as well as a concomitant decrease in CD45{sup +} bone marrow–derived cell (BMDC) migration (7.8% ± 2.2%) after PRT. The addition of AMD3100 also decreased CD45{sup +} BMDC migration in treated tumors (0.6% ± 0.1%). Higher vessel density was observed in treated tumors. No differences were observed in normal lung tissue after PRT or SRT. Conclusions: Pulsed RT–treated tumors exhibited slower growth and reduced hypoxia. Pulsed RT eliminated initiation of supportive mechanisms utilized by tumors in low oxygen microenvironments, including angiogenesis and recruitment of BMDCs.

  2. Large animal models for vaccine development and testing.

    Science.gov (United States)

    Gerdts, Volker; Wilson, Heather L; Meurens, Francois; van Drunen Littel-van den Hurk, Sylvia; Wilson, Don; Walker, Stewart; Wheler, Colette; Townsend, Hugh; Potter, Andrew A

    2015-01-01

    The development of human vaccines continues to rely on the use of animals for research. Regulatory authorities require novel vaccine candidates to undergo preclinical assessment in animal models before being permitted to enter the clinical phase in human subjects. Substantial progress has been made in recent years in reducing and replacing the number of animals used for preclinical vaccine research through the use of bioinformatics and computational biology to design new vaccine candidates. However, the ultimate goal of a new vaccine is to instruct the immune system to elicit an effective immune response against the pathogen of interest, and no alternatives to live animal use currently exist for evaluation of this response. Studies identifying the mechanisms of immune protection; determining the optimal route and formulation of vaccines; establishing the duration and onset of immunity, as well as the safety and efficacy of new vaccines, must be performed in a living system. Importantly, no single animal model provides all the information required for advancing a new vaccine through the preclinical stage, and research over the last two decades has highlighted that large animals more accurately predict vaccine outcome in humans than do other models. Here we review the advantages and disadvantages of large animal models for human vaccine development and demonstrate that much of the success in bringing a new vaccine to market depends on choosing the most appropriate animal model for preclinical testing. © The Author 2015. Published by Oxford University Press on behalf of the Institute for Laboratory Animal Research. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  3. Animal Models Used to Explore Abdominal Aortic Aneurysms

    DEFF Research Database (Denmark)

    Lysgaard Poulsen, J; Stubbe, J; Lindholt, J S

    2016-01-01

    OBJECTIVE: Experimental animal models have been used to investigate the formation, development, and progression of abdominal aortic aneurysms (AAAs) for decades. New models are constantly being developed to imitate the mechanisms of human AAAs and to identify treatments that are less risky than...... those used today. However, to the authors' knowledge, there is no model identical to the human AAA. The objective of this systematic review was to assess the different types of animal models used to investigate the development, progression, and treatment of AAA and to highlight their advantages...... and limitations. METHODS: A search protocol was used to perform a systematic literature search of PubMed and Embase. A total of 2,830 records were identified. After selection of the relevant articles, 564 papers on animal AAA models were included. RESULTS: The most common models in rodents, including elastase...

  4. Mouse Models Recapitulating Human Adrenocortical Tumors: What is lacking?

    Directory of Open Access Journals (Sweden)

    Felicia Leccia

    2016-07-01

    Full Text Available Adrenal cortex tumors are divided into benign forms such as primary hyperplasias and adrenocortical adenomas (ACAs, and malignant forms or adrenocortical carcinomas (ACCs. Primary hyperplasias are rare causes of ACTH-independent hypercortisolism. ACAs are the most common type of adrenal gland tumors and they are rarely functional, i.e producing steroids. When functional, adenomas result in endocrine disorders such as Cushing’s syndrome (hypercortisolism or Conn’s syndrome (hyperaldosteronism. In contrast, ACCs are extremely rare but highly aggressive tumors that may also lead to hypersecreting syndromes. Genetic analyses of patients with sporadic or familial forms of adrenocortical tumors led to the identification of potentially causative genes, most of them being involved in PKA, Wnt/β-catenin and P53 signaling pathways. Development of mouse models is a crucial step to firmly establish the functional significance of candidate genes, to dissect mechanisms leading to tumors and endocrine disorders and in fine to provide in vivo tools for therapeutic screens. In this article we will provide an overview on the existing mouse models (xenografted and genetically engineered of adrenocortical tumors by focusing on the role of PKA and Wnt/β-catenin pathways in this context. We will discuss the advantages and limitations of models that have been developed heretofore and we will point out necessary improvements in the development of next generation mouse models of adrenal diseases.

  5. The effect of the administration of iron on Ga-67 uptake in animal tumor and biodistribution

    International Nuclear Information System (INIS)

    Furukawa, Keiji

    1983-01-01

    In 1979 Larson reported that the uptake of Ga-67 in tumor cell was preceded by binding of the Ga-67 to transferrin. Since that time there have been many papers concerning changes in Ga-67 accumulation in experimental tumor by administration of iron before and after Ga-67 injection. This study was undertaken in the attempt to discern what changes are produced in Ga-67 images of tumor-bearing rabbits (VX-II) when iron was administered before and after Ga-67 injection. Additionally, the relationships between the change in the serum iron concentration in the tumor tissue in mice bearing Ehrlich's ascites tumor were studied. The following results were obtained. 1) The tumor uptake and biodistribution of Ga-67 following administration of iron in the form of Fesin (saccharated ferric oxide) or ferric-citrate is obviously diminished. This iron administration leads to an elevated excretion of Ga-67 from tumor and other organs except from bone. From this results, it was found that Ga-67 binds somewhat less avidity than iron to various iron transport protein. Accordingly, Ga-67 biodistribution may be markedly influenced by iron-loading. 2) The Ga-67 activity in blood following administration of iron was noted to suddenly markedly decrease. However, 24-48 hours after iron injection the Ga-67 activity in blood gradually increased. This result suggests that the Ga-67 displaced into the extravascular space by iron-loading reentered the vascular space when the iron concentration of serum returned to normal. 3) The accumulation of Ga-67 in the tumor and soft tissues was slightly decreased compared with controls after iron administration. However, the tumor to blood ratio (T/B) of Ga-67 in mice by iron loading was several time greater than that of Ga-67 alone because the clearance of Ga-67 from the blood was more accelated than that of tumor. The large tumor to blood ratio (T/B) would be advantageous in obtaining a more distinct tumor scan. (author)

  6. Preliminary study of experimental tumor radioimmunoimagination in animals by CA-50 monoclonal antibody

    International Nuclear Information System (INIS)

    Chen zhizhou

    1988-01-01

    The 125 I labelling of CA-50 monoclonal antibody, the distribution of radioactivity in experimental lung cancer 739 bearing mice, and tumor radioimmunoimagination were studied. At 24 hrs after the i.v. administrations of 5.55∼8.14 MBq 125 I-CA50, the relative values of radioactivity in different tissues were: muscle 1, blood 4.1, heart 1.4, liver 6.7, spleen 2.2, lung 2.8, kidney 5.3, tumor 14.5. Radioimmunoimagination showed clearly the locatization of the tumor

  7. Animal Models of Cystic Fibrosis Pathology: Phenotypic Parallels and Divergences

    Directory of Open Access Journals (Sweden)

    Gillian M. Lavelle

    2016-01-01

    Full Text Available Cystic fibrosis (CF is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR gene. The resultant characteristic ion transport defect results in decreased mucociliary clearance, bacterial colonisation, and chronic neutrophil-dominated inflammation. Much knowledge surrounding the pathophysiology of the disease has been gained through the generation of animal models, despite inherent limitations in each. The failure of certain mouse models to recapitulate the phenotypic manifestations of human disease has initiated the generation of larger animals in which to study CF, including the pig and the ferret. This review will summarise the basic phenotypes of three animal models and describe the contributions of such animal studies to our current understanding of CF.

  8. International Workshop on Mathematical Modeling of Tumor-Immune Dynamics

    CERN Document Server

    Kim, Peter; Mallet, Dann

    2014-01-01

    This collection of papers offers a broad synopsis of state-of-the-art mathematical methods used in modeling the interaction between tumors and the immune system. These papers were presented at the four-day workshop on Mathematical Models of Tumor-Immune System Dynamics held in Sydney, Australia from January 7th to January 10th, 2013. The workshop brought together applied mathematicians, biologists, and clinicians actively working in the field of cancer immunology to share their current research and to increase awareness of the innovative mathematical tools that are applicable to the growing field of cancer immunology. Recent progress in cancer immunology and advances in immunotherapy suggest that the immune system plays a fundamental role in host defense against tumors and could be utilized to prevent or cure cancer. Although theoretical and experimental studies of tumor-immune system dynamics have a long history, there are still many unanswered questions about the mechanisms that govern the interaction betwe...

  9. Cytomegalovirus Antivirals and Development of Improved Animal Models

    Science.gov (United States)

    McGregor, Alistair; Choi, K. Yeon

    2015-01-01

    Introduction Cytomegalovirus (CMV) is a ubiquitous pathogen that establishes a life long asymptomatic infection in healthy individuals. Infection of immunesuppressed individuals causes serious illness. Transplant and AIDS patients are highly susceptible to CMV leading to life threatening end organ disease. Another vulnerable population is the developing fetus in utero, where congenital infection can result in surviving newborns with long term developmental problems. There is no vaccine licensed for CMV and current antivirals suffer from complications associated with prolonged treatment. These include drug toxicity and emergence of resistant strains. There is an obvious need for new antivirals. Candidate intervention strategies are tested in controlled pre-clinical animal models but species specificity of HCMV precludes the direct study of the virus in an animal model. Areas covered This review explores the current status of CMV antivirals and development of new drugs. This includes the use of animal models and the development of new improved models such as humanized animal CMV and bioluminescent imaging of virus in animals in real time. Expert Opinion Various new CMV antivirals are in development, some with greater spectrum of activity against other viruses. Although the greatest need is in the setting of transplant patients there remains an unmet need for a safe antiviral strategy against congenital CMV. This is especially important since an effective CMV vaccine remains an elusive goal. In this capacity greater emphasis should be placed on suitable pre-clinical animal models and greater collaboration between industry and academia. PMID:21883024

  10. Brain tumor modeling using the CRISPR/Cas9 system: state of the art and view to the future.

    Science.gov (United States)

    Mao, Xiao-Yuan; Dai, Jin-Xiang; Zhou, Hong-Hao; Liu, Zhao-Qian; Jin, Wei-Lin

    2016-05-31

    Although brain tumors have been known tremendously over the past decade, there are still many problems to be solved. The etiology of brain tumors is not well understood and the treatment remains modest. There is in great need to develop a suitable brain tumor models that faithfully mirror the etiology of human brain neoplasm and subsequently get more efficient therapeutic approaches for these disorders. In this review, we described the current status of animal models of brain tumors and analyzed their advantages and disadvantages. Additionally, prokaryotic clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9), a versatile genome editing technology for investigating the functions of target genes, and its application were also introduced in our present work. We firstly proposed that brain tumor modeling could be well established via CRISPR/Cas9 techniques. And CRISPR/Cas9-mediated brain tumor modeling was likely to be more suitable for figuring out the pathogenesis of brain tumors, as CRISPR/Cas9 platform was a simple and more efficient biological toolbox for implementing mutagenesis of oncogenes or tumor suppressors that were closely linked with brain tumors.

  11. Review of Animal Models of Prostate Cancer Bone Metastasis

    Directory of Open Access Journals (Sweden)

    Jessica K. Simmons

    2014-06-01

    Full Text Available Prostate cancer bone metastases are associated with a poor prognosis and are considered incurable. Insight into the formation and growth of prostate cancer bone metastasis is required for development of new imaging and therapeutic strategies to combat this devastating disease. Animal models are indispensable in investigating cancer pathogenesis and evaluating therapeutics. Multiple animal models of prostate cancer bone metastasis have been developed, but few effectively model prostatic neoplasms and osteoblastic bone metastases as they occur in men. This review discusses the animal models that have been developed to investigate prostate cancer bone metastasis, with a focus on canine models and also includes human xenograft and rodent models. Adult dogs spontaneously develop benign prostatic hyperplasia and prostate cancer with osteoblastic bone metastases. Large animal models, such as dogs, are needed to develop new molecular imaging tools and effective focal intraprostatic therapy. None of the available models fully reflect the metastatic disease seen in men, although the various models have provided important insight into the metastatic process. As additional models are developed and knowledge from the different models is combined, the molecular mechanisms of prostate cancer bone metastasis can be deciphered and targeted for development of novel therapies and molecular diagnostic imaging.

  12. Sex differences in animal models of psychiatric disorders

    Science.gov (United States)

    Kokras, N; Dalla, C

    2014-01-01

    Psychiatric disorders are characterized by sex differences in their prevalence, symptomatology and treatment response. Animal models have been widely employed for the investigation of the neurobiology of such disorders and the discovery of new treatments. However, mostly male animals have been used in preclinical pharmacological studies. In this review, we highlight the need for the inclusion of both male and female animals in experimental studies aiming at gender-oriented prevention, diagnosis and treatment of psychiatric disorders. We present behavioural findings on sex differences from animal models of depression, anxiety, post-traumatic stress disorder, substance-related disorders, obsessive–compulsive disorder, schizophrenia, bipolar disorder and autism. Moreover, when available, we include studies conducted across different stages of the oestrous cycle. By inspection of the relevant literature, it is obvious that robust sex differences exist in models of all psychiatric disorders. However, many times results are conflicting, and no clear conclusion regarding the direction of sex differences and the effect of the oestrous cycle is drawn. Moreover, there is a lack of considerable amount of studies using psychiatric drugs in both male and female animals, in order to evaluate the differential response between the two sexes. Notably, while in most cases animal models successfully mimic drug response in both sexes, test parameters and treatment-sensitive behavioural indices are not always the same for male and female rodents. Thus, there is an increasing need to validate animal models for both sexes and use standard procedures across different laboratories. Linked Articles This article is part of a themed section on Animal Models in Psychiatry Research. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-20 PMID:24697577

  13. Animal models for the study of hepatitis B virus infection

    Directory of Open Access Journals (Sweden)

    Wei-Na Guo

    2018-01-01

    Full Text Available Even with an effective vaccine, an estimated 240 million people are chronically infected with hepatitis B virus (HBV worldwide. Current antiviral therapies, including interferon and nucleot(side analogues, rarely cure chronic hepatitis B. Animal models are very crucial for understanding the pathogenesis of chronic hepatitis B and developing new therapeutic drugs or strategies. HBV can only infect humans and chimpanzees, with the use of chimpanzees in HBV research strongly restricted. Thus, most advances in HBV research have been gained using mouse models with HBV replication or infection or models with HBV-related hepadnaviral infection. This review summarizes the animal models currently available for the study of HBV infection.

  14. Animal models of pulmonary emphysema: a stereologist's perspective

    Directory of Open Access Journals (Sweden)

    H. Fehrenbach

    2006-12-01

    Full Text Available A variety of animal models have been suggested as models of pulmonary emphysema; these are critically discussed in the present article from a stereologist's perspective. In addition, a stereological design for the quantification of experimentally induced emphysema is proposed. On the basis of the widely accepted definition of pulmonary emphysema being an "abnormal permanent enlargement of the airspaces distal to the terminal bronchioles, accompanied by destruction of their walls," quantitative morphology is the only method with which to reliably assess the presence of emphysema. Recognising this, careful inspection of animal models that are based on instillation of elastase, genetic alterations, inhalation of cigarette smoke or induction of apoptosis, reveals that both criteria of emphysema definition were demonstrated in surprisingly few of them. Several aspects are suggested to be critical for the understanding of animal models of human emphysema. For example, genetic models that rely on the inhibition of the formation of alveoli during post-natal alveolarisation should clearly be distinguished from models that rely on the loss of mature alveoli after alveolarisation is complete. Furthermore, inhalation models that are characterised by exposed animals exhibiting a severe loss of body weight should carefully examine the relative contribution of intervention and weight loss, respectively. Models that rely on the exposure of juvenile animals for several weeks or even months should take into account the effects of normal lung growth and ageing. Stereology offers appropriate tools with which to quantify the parameters relevant to assess development and the regeneration of emphysema. Stereologists continue to develop tools that will help ascertain the reliability of established and new models. If inappropriate parameters continue to be used for the evaluation of animal models of emphysema, thinking and resources are likely to be misdirected and the

  15. Elementary of animal model for percutaneous and ocular penetration

    Directory of Open Access Journals (Sweden)

    Kalpesh Chhotalal Ashara

    2016-12-01

    Full Text Available Models of animal are the most appropriate method for assessments of human in-vivo percutaneous and ocular penetrations. Monkey and rodents are used for the same. There are several nuts and bolts of each one, so it is necessary to study each one separately. Monkey, porcine and guinea pig penetration are correlated with that of human skin. The skin of rodents, lupus, pigs, etc. has more penetration properties than human skin. Rabbit, goat and sheep eye are mostly used for ocular penetration. The researcher also used hen’s egg chorioallantoic membrane test for ocular irritation study. The other animals’ cornea, cul-de-sac, eyeballs and prepared corneal epithelial models are very less in practice. Web-based alternative non-animal models are also available instead of animal models too. This article describes characteristics of monkeys, pigs, rats, rabbits, guinea pigs and hairless rodents, HuSki model, Cellophane® membrane, egg membrane, gelatin membrane, animal models for ophthalmic delivery, hen’s egg chorioallantoic membrane test, prepared corneal epithelial models and web-based alternative non-animal database.

  16. Apoptosis imaging studies in various animal models using radio-iodinated peptide.

    Science.gov (United States)

    Kwak, Wonjung; Ha, Yeong Su; Soni, Nisarg; Lee, Woonghee; Park, Se-Il; Ahn, Heesu; An, Gwang Il; Kim, In-San; Lee, Byung-Heon; Yoo, Jeongsoo

    2015-01-01

    Apoptosis has a role in many medical disorders and treatments; hence, its non-invasive evaluation is one of the most riveting research topics. Currently annexin V is used as gold standard for imaging apoptosis. However, several drawbacks, including high background, slow body clearance, make it a suboptimum marker for apoptosis imaging. In this study, we radiolabeled the recently identified histone H1 targeting peptide (ApoPep-1) and evaluated its potential as a new apoptosis imaging agent in various animal models. ApoPep-1 (CQRPPR) was synthesized, and an extra tyrosine residue was added to its N-terminal end for radiolabeling. This peptide was radiolabeled with (124)I and (131)I and was tested for its serum stability. Surgery- and drug-induced apoptotic rat models were prepared for apoptosis evaluation, and PET imaging was performed. Doxorubicin was used for xenograft tumor treatment in mice, and the induced apoptosis was studied. Tumor metabolism and proliferation were assessed by [(18)F]FDG and [(18)F]FLT PET imaging and compared with ApoPep-1 after doxorubicin treatment. The peptide was radiolabeled at high purity, and it showed reasonably good stability in serum. Cell death was easily imaged by radiolabeled ApoPep-1 in an ischemia surgery model. And, liver apoptosis was more clearly identified by ApoPep-1 rather than [(124)I]annexin V in cycloheximide-treated models. Three doxorubicin doses inhibited tumor growth, which was evaluated by 30-40% decreases of [(18)F]FDG and [(18)F]FLT PET uptake in the tumor area. However, ApoPep-1 demonstrated more than 200% increase in tumor uptake after chemotherapy, while annexin V did not show any meaningful uptake in the tumor compared with the background. Biodistribution data were also in good agreement with the microPET imaging results. All of the experimental data clearly demonstrated high potential of the radiolabeled ApoPep-1 for in vivo apoptosis imaging.

  17. Tumor dormancy and frailty models: A novel approach.

    Science.gov (United States)

    Rancoita, Paola M V; Valberg, Morten; Demicheli, Romano; Biganzoli, Elia; Di Serio, Clelia

    2017-03-01

    Frailty models are here proposed in the tumor dormancy framework, in order to account for possible unobservable dependence mechanisms in cancer studies where a non-negligible proportion of cancer patients relapses years or decades after surgical removal of the primary tumor. Relapses do not seem to follow a memory-less process, since their timing distribution leads to multimodal hazards. From a biomedical perspective, this behavior may be explained by tumor dormancy, i.e., for some patients microscopic tumor foci may remain asymptomatic for a prolonged time interval and, when they escape from dormancy, micrometastatic growth results in a clinical disease appearance. The activation of the growth phase at different metastatic states would explain the occurrence of metastatic recurrences and mortality at different times (multimodal hazard). We propose a new frailty model which includes in the risk function a random source of heterogeneity (frailty variable) affecting the components of the hazard function. Thus, the individual hazard rate results as the product of a random frailty variable and the sum of basic hazard rates. In tumor dormancy, the basic hazard rates correspond to micrometastatic developments starting from different initial states. The frailty variable represents the heterogeneity among patients with respect to relapse, which might be related to unknown mechanisms that regulate tumor dormancy. We use our model to estimate the overall survival in a large breast cancer dataset, showing how this improves the understanding of the underlying biological process. © 2016, The International Biometric Society.

  18. Models of 'obesity' in large animals and birds.

    Science.gov (United States)

    Clarke, Iain J

    2008-01-01

    Most laboratory-based research on obesity is carried out in rodents, but there are a number of other interesting models in the animal kingdom that are instructive. This includes domesticated animal species such as pigs and sheep, as well as wild, migrating and hibernating species. Larger animals allow particular experimental manipulations that are not possible in smaller animals and especially useful models have been developed to address issues such as manipulation of fetal development. Although some of the most well-studied models are ruminants, with metabolic control that differs from monogastrics, the general principles of metabolic regulation still pertain. It is possible to obtain much more accurate endocrine profiles in larger animals and this has provided important data in relation to leptin and ghrelin physiology. Genetic models have been created in domesticated animals through selection and these complement those of the laboratory rodent. This short review highlights particular areas of research in domesticated and wild species that expand our knowledge of systems that are important for our understanding of obesity and metabolism.

  19. Innovative Disease Model: Zebrafish as an In Vivo Platform for Intestinal Disorder and Tumors

    Directory of Open Access Journals (Sweden)

    Jeng-Wei Lu

    2017-09-01

    Full Text Available Colorectal cancer (CRC is one of the world’s most common cancers and is the second leading cause of cancer deaths, causing more than 50,000 estimated deaths each year. Several risk factors are highly associated with CRC, including being overweight, eating a diet high in red meat and over-processed meat, having a history of inflammatory bowel disease, and smoking. Previous zebrafish studies have demonstrated that multiple oncogenes and tumor suppressor genes can be regulated through genetic or epigenetic alterations. Zebrafish research has also revealed that the activation of carcinogenesis-associated signal pathways plays an important role in CRC. The biology of cancer, intestinal disorders caused by carcinogens, and the morphological patterns of tumors have been found to be highly similar between zebrafish and humans. Therefore, the zebrafish has become an important animal model for translational medical research. Several zebrafish models have been developed to elucidate the characteristics of gastrointestinal diseases. This review article focuses on zebrafish models that have been used to study human intestinal disorders and tumors, including models involving mutant and transgenic fish. We also report on xenograft models and chemically-induced enterocolitis. This review demonstrates that excellent zebrafish models can provide novel insights into the pathogenesis of gastrointestinal diseases and help facilitate the evaluation of novel anti-tumor drugs.

  20. OBESITY AND CRITICAL ILLNESS: INSIGHTS FROM ANIMAL MODELS.

    Science.gov (United States)

    Mittwede, Peter N; Clemmer, John S; Bergin, Patrick F; Xiang, Lusha

    2016-04-01

    Critical illness is a major cause of morbidity and mortality around the world. While obesity is often detrimental in the context of trauma, it is paradoxically associated with improved outcomes in some septic patients. The reasons for these disparate outcomes are not well understood. A number of animal models have been used to study the obese response to various forms of critical illness. Just as there have been many animal models that have attempted to mimic clinical conditions, there are many clinical scenarios that can occur in the highly heterogeneous critically ill patient population that occupies hospitals and intensive care units. This poses a formidable challenge for clinicians and researchers attempting to understand the mechanisms of disease and develop appropriate therapies and treatment algorithms for specific subsets of patients, including the obese. The development of new, and the modification of existing animal models, is important in order to bring effective treatments to a wide range of patients. Not only do experimental variables need to be matched as closely as possible to clinical scenarios, but animal models with pre-existing comorbid conditions need to be studied. This review briefly summarizes animal models of hemorrhage, blunt trauma, traumatic brain injury, and sepsis. It also discusses what has been learned through the use of obese models to study the pathophysiology of critical illness in light of what has been demonstrated in the clinical literature.

  1. Cytoreductive Chemotherapy Improves the Biodistribution of Antibodies Directed Against Tumor Necrosis in Murine Solid Tumor Models

    Science.gov (United States)

    Jang, Julie K.; Khawli, Leslie A.; Park, Ryan; Wu, Brian W.; Li, Zibo; Canter, David; Conti, Peter S.; Epstein, Alan L.

    2013-01-01

    Current strategies in cancer treatment employ combinations of different treatment modalities, which include chemotherapy, radiotherapy, immunotherapy, and surgery. Consistent with that approach, the present study demonstrates how chemotherapeutic agents can potentiate the delivery of radiolabeled, necrosis-targeting antibodies (chTNT-3, NHS76) to tumor. All chemotherapeutics in this study (5-fluorouracil, etoposide, vinblastine, paclitaxel, and doxorubicin) resulted in statistically significant increases in tumor uptake of radiolabeled antibodies and their F(ab')2 fragments compared to no pretreatment with chemotherapy. Labeled antibodies were administered at various time points following a single dose of chemotherapy in multiple tumor models, and the biodistribution of the antibodies were determined by measuring radioactivity in harvested tissues. MicroPET/CT was also done to demonstrate clinical relevancy of using chemotherapy pretreatment to increase antibody uptake. Results of biodistribution and imaging data reveal specific time frames following chemotherapy when necrosis-targeting antibodies are best delivered, either for imaging or radiotherapy. Thus, the present work offers the prospect of using cytoreductive chemotherapy to increase tumor accumulation of select therapeutic antibodies, especially when combined with other forms of immunotherapy, for the successful treatment of solid tumors. PMID:24130055

  2. MicroRNA signature characterizes primary tumors that metastasize in an esophageal adenocarcinoma rat model.

    Directory of Open Access Journals (Sweden)

    Ali H Zaidi

    Full Text Available To establish a miRNA signature for metastasis in an animal model of esophageal adenocarcinoma (EAC.The incidence of esophageal adenocarcinoma (EAC has dramatically increased and esophageal cancer is now the sixth leading cause of cancer deaths worldwide. Mortality rates remain high among patients with advanced stage disease and esophagectomy is associated with high complication rates. Hence, early identification of potentially metastatic disease would better guide treatment strategies.The modified Levrat's surgery was performed to induce EAC in Sprague-Dawley rats. Primary EAC and distant metastatic sites were confirmed via histology and immunofluorescence. miRNA profiling was performed on primary tumors with or without metastasis. A unique subset of miRNAs expressed in primary tumors and metastases was identified with Ingenuity Pathway Analysis (IPA along with upstream and downstream targets. miRNA-linked gene expression analysis was performed on a secondary cohort of metastasis positive (n=5 and metastasis negative (n=28 primary tumors.The epithelial origin of distant metastasis was established by IF using villin (VIL1 and mucin 5AC (MUC5AC antibodies. miRNome analysis identified four down-regulated miRNAs in metastasis positive primary tumors compared to metastasis negative tumors: miR-92a-3p (p=0.0001, miR-141-3p (p=0.0022, miR-451-1a (p=0.0181 and miR133a-3p (p=0.0304. Six target genes identified in the top scoring networks by IPA were validated as significantly, differentially expressed in metastasis positive primary tumors: Ago2, Akt1, Kras, Bcl2L11, CDKN1B and Zeb2.In vivo metastasis was confirmed in the modified Levrat's model. Analysis of the primary tumor identified a distinctive miRNA signature for primary tumors that metastasized.

  3. Cellular Interaction and Tumoral Penetration Properties of Cyclodextrin Nanoparticles on 3D Breast Tumor Model

    Directory of Open Access Journals (Sweden)

    Gamze Varan

    2018-01-01

    Full Text Available Amphiphilic cyclodextrins are biocompatible oligosaccharides that can be used for drug delivery especially for the delivery of drugs with solubility problems thanks to their unique molecular structures. In this paper, Paclitaxel was used as a model anticancer drug to determine the inclusion complex properties of amphiphilic cyclodextrins with different surface charge. Paclitaxel-loaded cyclodextrin nanoparticles were characterized in terms of mean particle diameter, zeta potential, encapsulation efficacy, drug release profile and cell culture studies. It was determined that the nanoparticles prepared from the inclusion complex according to characterization studies have a longer release profile than the conventionally prepared nanoparticles. In order to mimic the tumor microenvironment, breast cancer cells and healthy fibroblast cells were used in 3-dimensional (3D cell culture studies. It was determined that the activities of nanoparticles prepared by conventional methods behave differently in 2-dimensional (2D and 3D cell cultures. In addition, it was observed that the nanoparticles prepared from the inclusion complex have a stronger anti-tumoral activity in the 3D multicellular tumor model than the drug solution. Furthermore, polycationic amphiphilic cyclodextrin nanoparticles can diffuse and penetrate through multilayer cells in a 3D tumor model, which is crucial for an eventual antitumor effect.

  4. Modeling evolutionary dynamics of epigenetic mutations in hierarchically organized tumors.

    Directory of Open Access Journals (Sweden)

    Andrea Sottoriva

    2011-05-01

    Full Text Available The cancer stem cell (CSC concept is a highly debated topic in cancer research. While experimental evidence in favor of the cancer stem cell theory is apparently abundant, the results are often criticized as being difficult to interpret. An important reason for this is that most experimental data that support this model rely on transplantation studies. In this study we use a novel cellular Potts model to elucidate the dynamics of established malignancies that are driven by a small subset of CSCs. Our results demonstrate that epigenetic mutations that occur during mitosis display highly altered dynamics in CSC-driven malignancies compared to a classical, non-hierarchical model of growth. In particular, the heterogeneity observed in CSC-driven tumors is considerably higher. We speculate that this feature could be used in combination with epigenetic (methylation sequencing studies of human malignancies to prove or refute the CSC hypothesis in established tumors without the need for transplantation. Moreover our tumor growth simulations indicate that CSC-driven tumors display evolutionary features that can be considered beneficial during tumor progression. Besides an increased heterogeneity they also exhibit properties that allow the escape of clones from local fitness peaks. This leads to more aggressive phenotypes in the long run and makes the neoplasm more adaptable to stringent selective forces such as cancer treatment. Indeed when therapy is applied the clone landscape of the regrown tumor is more aggressive with respect to the primary tumor, whereas the classical model demonstrated similar patterns before and after therapy. Understanding these often counter-intuitive fundamental properties of (non-hierarchically organized malignancies is a crucial step in validating the CSC concept as well as providing insight into the therapeutical consequences of this model.

  5. Precise MRI-based stereotaxic surgery in large animal models

    DEFF Research Database (Denmark)

    Glud, A. N.; Bech, J.; Tvilling, L.

    and subcortical anatomical differences. NEW METHOD: We present a convenient method to make an MRI-visible skull fiducial for 3D MRI-based stereotaxic procedures in larger experimental animals. Plastic screws were filled with either copper-sulphate solution or MRI-visible paste from a commercially available......BACKGROUND: Stereotaxic neurosurgery in large animals is used widely in different sophisticated models, where precision is becoming more crucial as desired anatomical target regions are becoming smaller. Individually calculated coordinates are necessary in large animal models with cortical...... cranial head marker. The screw fiducials were inserted in the animal skulls and T1 weighted MRI was performed allowing identification of the inserted skull marker. RESULTS: Both types of fiducial markers were clearly visible on the MRÍs. This allows high precision in the stereotaxic space. COMPARISON...

  6. Procoagulant snake venoms have differential effects in animal plasmas: Implications for antivenom testing in animal models.

    Science.gov (United States)

    Maduwage, Kalana P; Scorgie, Fiona E; Lincz, Lisa F; O'Leary, Margaret A; Isbister, Geoffrey K

    2016-01-01

    Animal models are used to test toxic effects of snake venoms/toxins and the antivenom required to neutralise them. However, venoms that cause clinically relevant coagulopathy in humans may have differential effects in animals. We aimed to investigate the effect of different procoagulant snake venoms on various animal plasmas. Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen and D-dimer levels were measured in seven animal plasmas (human, rabbit, cat, guinea pig, pig, cow and rat). In vitro clotting times were then used to calculate the effective concentration (EC50) in each plasma for four snake venoms with different procoagulant toxins: Pseudonaja textilis, Daboia russelli, Echis carinatus and Calloselasma rhodostoma. Compared to human, PT and aPTT were similar for rat, rabbit and pig, but double for cat and cow, while guinea pig had similar aPTT but double PT. Fibrinogen and D-dimer levels were similar for all species. Human and rabbit plasmas had the lowest EC50 for P. textilis (0.1 and 0.4 μg/ml), D. russelli (0.4 and 0.1 μg/ml), E. carinatus (0.6 and 0.1 μg/ml) venoms respectively, while cat plasma had the lowest EC50 for C. rhodostoma (11 μg/ml) venom. Cow, rat, pig and guinea pig plasmas were highly resistant to all four venoms with EC50 10-fold that of human. Different animal plasmas have varying susceptibility to procoagulant venoms, and excepting rabbits, animal models are not appropriate to test procoagulant activity. In vitro assays on human plasma should instead be adopted for this purpose. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Advancing research on animal-transported subsidies by integrating animal movement and ecosystem modelling.

    Science.gov (United States)

    Earl, Julia E; Zollner, Patrick A

    2017-09-01

    Connections between ecosystems via animals (active subsidies) support ecosystem services and contribute to numerous ecological effects. Thus, the ability to predict the spatial distribution of active subsidies would be useful for ecology and conservation. Previous work modelling active subsidies focused on implicit space or static distributions, which treat passive and active subsidies similarly. Active subsidies are fundamentally different from passive subsidies, because animals can respond to the process of subsidy deposition and ecosystem changes caused by subsidy deposition. We propose addressing this disparity by integrating animal movement and ecosystem ecology to advance active subsidy investigations, make more accurate predictions of subsidy spatial distributions, and enable a mechanistic understanding of subsidy spatial distributions. We review selected quantitative techniques that could be used to accomplish integration and lead to novel insights. The ultimate objective for these types of studies is predictions of subsidy spatial distributions from characteristics of the subsidy and the movement strategy employed by animals that transport subsidies. These advances will be critical in informing the management of ecosystem services, species conservation and ecosystem degradation related to active subsidies. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

  8. Research advances in animal models of nonalcoholic fatty liver disease

    Directory of Open Access Journals (Sweden)

    HUANG Haiyan

    2014-09-01

    Full Text Available In recent years, the incidence of nonalcoholic fatty liver disease (NAFLD has increased gradually along with the rising prevalence of obesity, type 2 diabetes, and hyperlipidemia, and NAFLD has become one of the most common chronic liver diseases in the world and the second major liver disease after chronic viral hepatitis in China. However, its pathogenesis has not yet been clarified. Animal models are playing an important role in researches on NAFLD due to the facts that the development and progression of NAFLD require a long period of time, and ethical limitations exist in conducting drug trials in patients or collecting liver tissues from patients. The animal models with histopathology similar to that of NAFLD patients are reviewed, and their modeling principle, as well as the advantages and disadvantages, are compared. Animal models provide a powerful tool for further studies of NAFLD pathogenesis and drug screening for prevention and treatment of NAFLD.

  9. Animal models for the study of Helicobacter pylori infection

    Directory of Open Access Journals (Sweden)

    Eliza Miszczyk

    2014-05-01

    Full Text Available The Gram-negative bacillus Helicobacter pylori is widely recognized as a major etiologic agent responsible for chronic active gastritis, peptic ulcers, the development of gastric cancer and mucosa-associated lymphoid tissue (MALT lymphoma. Still, little is known about the natural history of H. pylori infection, since patients usually after many years of not suffering from symptoms of the infection are simply asymptomatic. Since the research investigators carried out on human models has many limitations, there is an urgent need for the development of an animal model optimal and suitable for the monitoring of H. pylori infections. This review summarizes the recent findings on the suitability of animal models used in H. pylori research. Several animal models are useful for the assessment of pathological, microbiological and immunological consequences of infection, which makes it possible to monitor the natural

  10. Th17 in Animal Models of Rheumatoid Arthritis

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    Motomu Hashimoto

    2017-07-01

    Full Text Available IL-17-secreting helper CD4 T cells (Th17 cells constitute a newly identified subset of helper CD4 T cells that play a key role in the development of rheumatoid arthritis (RA in its animal models. Recently, several models of spontaneous RA, which elucidate the mechanism of RA onset, have been discovered. These animal models shed new light on the role of Th17 in the development of autoimmune arthritis. Th17 cells coordinate inflammation and promote joint destruction, acting on various cells, including neutrophils, macrophages, synovial fibroblasts, and osteoclasts. Regulatory T cells cannot control Th17 cells under conditions of inflammation. In this review, the pathogenic role of Th17 cells in arthritis development, which was revealed by the recent animal models of RA, is discussed.

  11. Th17 in Animal Models of Rheumatoid Arthritis.

    Science.gov (United States)

    Hashimoto, Motomu

    2017-07-21

    IL-17-secreting helper CD4 T cells (Th17 cells) constitute a newly identified subset of helper CD4 T cells that play a key role in the development of rheumatoid arthritis (RA) in its animal models. Recently, several models of spontaneous RA, which elucidate the mechanism of RA onset, have been discovered. These animal models shed new light on the role of Th17 in the development of autoimmune arthritis. Th17 cells coordinate inflammation and promote joint destruction, acting on various cells, including neutrophils, macrophages, synovial fibroblasts, and osteoclasts. Regulatory T cells cannot control Th17 cells under conditions of inflammation. In this review, the pathogenic role of Th17 cells in arthritis development, which was revealed by the recent animal models of RA, is discussed.

  12. Animal Models for Tuberculosis in Translational and Precision Medicine

    Directory of Open Access Journals (Sweden)

    Lingjun Zhan

    2017-05-01

    Full Text Available Tuberculosis (TB is a health threat to the global population. Anti-TB drugs and vaccines are key approaches for TB prevention and control. TB animal models are basic tools for developing biomarkers of diagnosis, drugs for therapy, vaccines for prevention and researching pathogenic mechanisms for identification of targets; thus, they serve as the cornerstone of comparative medicine, translational medicine, and precision medicine. In this review, we discuss the current use of TB animal models and their problems, as well as offering perspectives on the future of these models.

  13. ANIMAL MODELS OF POST-TRAUMATIC STRESS DISORDER: FACE VALIDITY

    Directory of Open Access Journals (Sweden)

    SONAL eGOSWAMI

    2013-05-01

    Full Text Available Post-traumatic stress disorder (PTSD is a debilitating condition that develops in a proportion of individuals following a traumatic event. Despite recent advances, ethical limitations associated with human research impede progress in understanding PTSD. Fortunately, much effort has focused on developing animal models to help study the pathophysiology of PTSD. Here, we provide an overview of animal PTSD models where a variety of stressors (physical, psychosocial, or psychogenic are used to examine the long-term effects of severe trauma. We emphasize models involving predator threat because they reproduce human individual differences in susceptibility to, and in the long-term consequences of, psychological trauma.

  14. Animal models of post-traumatic stress disorder: face validity

    Science.gov (United States)

    Goswami, Sonal; Rodríguez-Sierra, Olga; Cascardi, Michele; Paré, Denis

    2013-01-01

    Post-traumatic stress disorder (PTSD) is a debilitating condition that develops in a proportion of individuals following a traumatic event. Despite recent advances, ethical limitations associated with human research impede progress in understanding PTSD. Fortunately, much effort has focused on developing animal models to help study the pathophysiology of PTSD. Here, we provide an overview of animal PTSD models where a variety of stressors (physical, psychosocial, or psychogenic) are used to examine the long-term effects of severe trauma. We emphasize models involving predator threat because they reproduce human individual differences in susceptibility to, and in the long-term consequences of, psychological trauma. PMID:23754973

  15. Animal Models for Tuberculosis in Translational and Precision Medicine.

    Science.gov (United States)

    Zhan, Lingjun; Tang, Jun; Sun, Mengmeng; Qin, Chuan

    2017-01-01

    Tuberculosis (TB) is a health threat to the global population. Anti-TB drugs and vaccines are key approaches for TB prevention and control. TB animal models are basic tools for developing biomarkers of diagnosis, drugs for therapy, vaccines for prevention and researching pathogenic mechanisms for identification of targets; thus, they serve as the cornerstone of comparative medicine, translational medicine, and precision medicine. In this review, we discuss the current use of TB animal models and their problems, as well as offering perspectives on the future of these models.

  16. Animal Models for the Study of Female Sexual Dysfunction

    Science.gov (United States)

    Marson, Lesley; Giamberardino, Maria Adele; Costantini, Raffaele; Czakanski, Peter; Wesselmann, Ursula

    2017-01-01

    Introduction Significant progress has been made in elucidating the physiological and pharmacological mechanisms of female sexual function through preclinical animal research. The continued development of animal models is vital for the understanding and treatment of the many diverse disorders that occur in women. Aim To provide an updated review of the experimental models evaluating female sexual function that may be useful for clinical translation. Methods Review of English written, peer-reviewed literature, primarily from 2000 to 2012, that described studies on female sexual behavior related to motivation, arousal, physiological monitoring of genital function and urogenital pain. Main Outcomes Measures Analysis of supporting evidence for the suitability of the animal model to provide measurable indices related to desire, arousal, reward, orgasm, and pelvic pain. Results The development of female animal models has provided important insights in the peripheral and central processes regulating sexual function. Behavioral models of sexual desire, motivation, and reward are well developed. Central arousal and orgasmic responses are less well understood, compared with the physiological changes associated with genital arousal. Models of nociception are useful for replicating symptoms and identifying the neurobiological pathways involved. While in some cases translation to women correlates with the findings in animals, the requirement of circulating hormones for sexual receptivity in rodents and the multifactorial nature of women’s sexual function requires better designed studies and careful analysis. The current models have studied sexual dysfunction or pelvic pain in isolation; combining these aspects would help to elucidate interactions of the pathophysiology of pain and sexual dysfunction. Conclusions Basic research in animals has been vital for understanding the anatomy, neurobiology, and physiological mechanisms underlying sexual function and urogenital pain

  17. Food allergy: What do we learn from animal models?

    NARCIS (Netherlands)

    Knippels, L.M.J.; Wijk, F. van; Penninks, A.H.

    2004-01-01

    Purpose of review This review summarizes selected articles on animal models of food allergy published in 2003. The research areas that are covered include mechanistic studies, the search for new therapies, as well as screening models for hazard identification of potential allergens. Recent findings

  18. Animal models for human genetic diseases | Sharif | African Journal ...

    African Journals Online (AJOL)

    The study of human genetic diseases can be greatly aided by animal models because of their similarity to humans in terms of genetics. In addition to understand diverse aspects of basic biology, model organisms are extensively used in applied research in agriculture, industry, and also in medicine, where they are used to ...

  19. An animal model to train Lichtenstein inguinal hernia repair

    DEFF Research Database (Denmark)

    Rosenberg, J; Presch, I; Pommergaard, H C

    2013-01-01

    pigs, and a total of 55 surgeons have been educated to perform Lichtenstein's hernia repair in these animals. CONCLUSIONS: This new experimental surgical model for training Lichtenstein's hernia repair mimics the human inguinal anatomy enough to make it suitable as a training model. The operation...

  20. Obsessive-compulsive disorder: Insights from animal models.

    Science.gov (United States)

    Szechtman, Henry; Ahmari, Susanne E; Beninger, Richard J; Eilam, David; Harvey, Brian H; Edemann-Callesen, Henriette; Winter, Christine

    2017-05-01

    Research with animal models of obsessive-compulsive disorder (OCD) shows the following: (1) Optogenetic studies in mice provide evidence for a plausible cause-effect relation between increased activity in cortico-basal ganglia-thalamo-cortical (CBGTC) circuits and OCD by demonstrating the induction of compulsive behavior with the experimental manipulation of the CBGTC circuit. (2) Parallel use of several animal models is a fruitful paradigm to examine the mechanisms of treatment effects of deep brain stimulation in distinct OCD endophenotypes. (3) Features of spontaneous behavior in deer mice constitute a rich platform to investigate the neurobiology of OCD, social ramifications of a compulsive phenotype, and test novel drugs. (4) Studies in animal models for psychiatric disorders comorbid with OCD suggest comorbidity may involve shared neural circuits controlling expression of compulsive behavior. (5) Analysis of compulsive behavior into its constitutive components provides evidence from an animal model for a motivational perspective on OCD. (6) Methods of behavioral analysis in an animal model translate to dissection of compulsive rituals in OCD patients, leading to diagnostic tests. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Chest compressions in newborn animal models: A review.

    Science.gov (United States)

    Solevåg, Anne Lee; Cheung, Po-Yin; Lie, Helene; O'Reilly, Megan; Aziz, Khalid; Nakstad, Britt; Schmölzer, Georg Marcus

    2015-11-01

    Much of the knowledge about the optimal way to perform chest compressions (CC) in newborn infants is derived from animal studies. The objective of this review was to identify studies of CC in newborn term animal models and review the evidence. We also provide an overview of the different models. MEDLINE, EMBASE and CINAHL, until September 29th 2014. Study eligibility criteria and interventions: term newborn animal models where CC was performed. Based on 419 retrieved studies from MEDLINE and 502 from EMBASE, 28 studies were included. No additional studies were identified in CINAHL. Most of the studies were performed in pigs after perinatal transition without long-term follow-up. The models differed widely in methodological aspects, which limits the possibility to compare and synthesize findings. Studies uncommonly reported the method for randomization and allocation concealment, and a limited number were blinded. Only the evidence in favour of the two-thumb encircling hands technique for performing CC, a CC to ventilation ratio of 3:1; and that air can be used for ventilation during CC; was supported by more than one study. Animal studies should be performed and reported with the same rigor as in human randomized trials. Good transitional and survival models are needed to further increase the strength of the evidence derived from animal studies of newborn chest compressions. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. How animal models inform child and adolescent psychiatry.

    Science.gov (United States)

    Stevens, Hanna E; Vaccarino, Flora M

    2015-05-01

    Every available approach should be used to advance the field of child and adolescent psychiatry. Biological systems are important for the behavioral problems of children. Close examination of nonhuman animals and the biology and behavior that they share with humans is an approach that must be used to advance the clinical work of child psychiatry. We review here how model systems are used to contribute to significant insights into childhood psychiatric disorders. Model systems have not only demonstrated causality of risk factors for psychiatric pathophysiology, but have also allowed child psychiatrists to think in different ways about risks for psychiatric disorders and multiple levels that might be the basis of recovery and prevention. We present examples of how animal systems are used to benefit child psychiatry, including through environmental, genetic, and acute biological manipulations. Animal model work has been essential in our current thinking about childhood disorders, including the importance of dose and timing of risk factors, specific features of risk factors that are significant, neurochemistry involved in brain functioning, molecular components of brain development, and the importance of cellular processes previously neglected in psychiatric theories. Animal models have clear advantages and disadvantages that must be considered for these systems to be useful. Coupled with increasingly sophisticated methods for investigating human behavior and biology, animal model systems will continue to make essential contributions to our field. Copyright © 2015 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

  3. Animal models of GM2 gangliosidosis: utility and limitations

    Directory of Open Access Journals (Sweden)

    Lawson CA

    2016-07-01

    Full Text Available Cheryl A Lawson,1,2 Douglas R Martin2,3 1Department of Pathobiology, 2Scott-Ritchey Research Center, 3Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL, USA Abstract: GM2 gangliosidosis, a subset of lysosomal storage disorders, is caused by a deficiency of the glycohydrolase, β-N-acetylhexosaminidase, and includes the closely related Tay–Sachs and Sandhoff diseases. The enzyme deficiency prevents the normal, stepwise degradation of ganglioside, which accumulates unchecked within the cellular lysosome, particularly in neurons. As a result, individuals with GM2 gangliosidosis experience progressive neurological diseases including motor deficits, progressive weakness and hypotonia, decreased responsiveness, vision deterioration, and seizures. Mice and cats are well-established animal models for Sandhoff disease, whereas Jacob sheep are the only known laboratory animal model of Tay–Sachs disease to exhibit clinical symptoms. Since the human diseases are relatively rare, animal models are indispensable tools for further study of pathogenesis and for development of potential treatments. Though no effective treatments for gangliosidoses currently exist, animal models have been used to test promising experimental therapies. Herein, the utility and limitations of gangliosidosis animal models and how they have contributed to the development of potential new treatments are described. Keywords: GM2 gangliosidosis, Tay–Sachs disease, Sandhoff disease, lysosomal storage disorder, sphingolipidosis, brain disease

  4. Animal models of GM2 gangliosidosis: utility and limitations.

    Science.gov (United States)

    Lawson, Cheryl A; Martin, Douglas R

    2016-01-01

    GM2 gangliosidosis, a subset of lysosomal storage disorders, is caused by a deficiency of the glycohydrolase, β-N-acetylhexosaminidase, and includes the closely related Tay-Sachs and Sandhoff diseases. The enzyme deficiency prevents the normal, stepwise degradation of ganglioside, which accumulates unchecked within the cellular lysosome, particularly in neurons. As a result, individuals with GM2 gangliosidosis experience progressive neurological diseases including motor deficits, progressive weakness and hypotonia, decreased responsiveness, vision deterioration, and seizures. Mice and cats are well-established animal models for Sandhoff disease, whereas Jacob sheep are the only known laboratory animal model of Tay-Sachs disease to exhibit clinical symptoms. Since the human diseases are relatively rare, animal models are indispensable tools for further study of pathogenesis and for development of potential treatments. Though no effective treatments for gangliosidoses currently exist, animal models have been used to test promising experimental therapies. Herein, the utility and limitations of gangliosidosis animal models and how they have contributed to the development of potential new treatments are described.

  5. Analysis of mice tumor models using dynamic MRI data and a dedicated software platform

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    Alfke, H.; Maurer, E.; Klose, K.J. [Philipps Univ. Marburg (Germany). Dept. of Radiology; Kohle, S.; Rascher-Friesenhausen, R.; Behrens, S.; Peitgen, H.O. [MeVis - Center for Medical Diagnostic Systems and Visualization, Bremen (Germany); Celik, I. [Philipps Univ. Marburg (Germany). Inst. for Theoretical Surgery; Heverhagen, J.T. [Philipps Univ. Marburg (Germany). Dept. of Radiology; Ohio State Univ., Columbus (United States). Dept. of Radiology

    2004-09-01

    Purpose: To implement a software platform (DynaVision) dedicated to analyze data from functional imaging of tumors with different mathematical approaches, and to test the software platform in pancreatic carcinoma xenografts in mice with severe combined immunodeficiency disease (SCID). Materials and Methods: A software program was developed for extraction and visualization of tissue perfusion parameters from dynamic contrast-enhanced images. This includes regional parameter calculation from enhancement curves, parametric images (e.g., blood flow), animation, 3D visualization, two-compartment modeling a mode for comparing different datasets (e.g., therapy monitoring), and motion correction. We analyzed xenograft tumors from two pancreatic carcinoma cell lines (B x PC3 and ASPC1) implanted in 14 SCID mice after injection of Gd-DTPA into the tail vein. These data were correlated with histopathological findings. Results: Image analysis was completed in approximately 15 minutes per data set. The possibility of drawing and editing ROIs within the whole data set makes it easy to obtain quantitative data from the intensity-time curves. In one animal, motion artifacts reduced the image quality to a greater extent but data analysis was still possible after motion correction. Dynamic MRI of mice tumor models revealed a highly heterogeneous distribution of the contrast-enhancement curves and derived parameters, which correlated with differences in histopathology. ASPc1 tumors showed a more hypervascular type of curves with faster and higher signal enhancement rate (wash-in) and a faster signal decrease (wash-out). BXPC3 tumors showed a more hypovascular type with slower wash-in and wash-out. This correlated with the biological properties of the tumors. (orig.)

  6. Analysis of mice tumor models using dynamic MRI data and a dedicated software platform

    International Nuclear Information System (INIS)

    Alfke, H.; Maurer, E.; Klose, K.J.; Celik, I.; Heverhagen, J.T.; Ohio State Univ., Columbus

    2004-01-01

    Purpose: To implement a software platform (DynaVision) dedicated to analyze data from functional imaging of tumors with different mathematical approaches, and to test the software platform in pancreatic carcinoma xenografts in mice with severe combined immunodeficiency disease (SCID). Materials and Methods: A software program was developed for extraction and visualization of tissue perfusion parameters from dynamic contrast-enhanced images. This includes regional parameter calculation from enhancement curves, parametric images (e.g., blood flow), animation, 3D visualization, two-compartment modeling a mode for comparing different datasets (e.g., therapy monitoring), and motion correction. We analyzed xenograft tumors from two pancreatic carcinoma cell lines (B x PC3 and ASPC1) implanted in 14 SCID mice after injection of Gd-DTPA into the tail vein. These data were correlated with histopathological findings. Results: Image analysis was completed in approximately 15 minutes per data set. The possibility of drawing and editing ROIs within the whole data set makes it easy to obtain quantitative data from the intensity-time curves. In one animal, motion artifacts reduced the image quality to a greater extent but data analysis was still possible after motion correction. Dynamic MRI of mice tumor models revealed a highly heterogeneous distribution of the contrast-enhancement curves and derived parameters, which correlated with differences in histopathology. ASPc1 tumors showed a more hypervascular type of curves with faster and higher signal enhancement rate (wash-in) and a faster signal decrease (wash-out). BXPC3 tumors showed a more hypovascular type with slower wash-in and wash-out. This correlated with the biological properties of the tumors. (orig.)

  7. Pioglitazone treatment increases survival and prevents body weight loss in tumor-bearing animals: possible anti-cachectic effect.

    Directory of Open Access Journals (Sweden)

    Mércia Beluzi

    Full Text Available Cachexia is a multifactorial syndrome characterized by profound involuntary weight loss, fat depletion, skeletal muscle wasting, and asthenia; all symptoms are not entirely attributable to inadequate nutritional intake. Adipose tissue and skeletal muscle loss during cancer cachexia development has been described systematically. The former was proposed to precede and be more rapid than the latter, which presents a means for the early detection of cachexia in cancer patients. Recently, pioglitazone (PGZ was proposed to exhibit anti-cancer properties, including a reduction in insulin resistance and adipose tissue loss; nevertheless, few studies have evaluated its effect on survival. For greater insight into a potential anti-cachectic effect due to PGZ, 8-week-old male Wistar rats were subcutaneously inoculated with 1 mL (2×107 of Walker 256 tumor cells. The animals were randomly assigned to two experimental groups: TC (tumor + saline-control and TP5 (tumor + PGZ/5 mg. Body weight, food ingestion and tumor growth were measured at baseline and after removal of tumor on days 7, 14 and 26. Samples from different visceral adipose tissue (AT depots were collected on days 7 and 14 and stored at -80o C (5 to 7 animals per day/group. The PGZ treatment showed an increase in the survival average of 27.3% (P< 0.01 when compared to TC. It was also associated with enhanced body mass preservation (40.7 and 56.3%, p< 0.01 on day 14 and 26 compared with the TC group. The treatment also reduced the final tumor mass (53.4%, p<0.05 and anorexia compared with the TC group during late-stage cachexia. The retroperitoneal AT (RPAT mass was preserved on day 7 compared with the TC group during the same experimental period. Such effect also demonstrates inverse relationship with tumor growth, on day 14. Gene expression of PPAR-γ, adiponectin, LPL and C/EBP-α from cachectic rats was upregulated after PGZ. Glucose uptake from adipocyte cells (RPAT was entirely re

  8. The use of animal models in behavioural neuroscience research.

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    Bovenkerk, Bernice; Kaldewaij, Frederike

    2015-01-01

    Animal models are used in experiments in the behavioural neurosciences that aim to contribute to the prevention and treatment of cognitive and affective disorders in human beings, such as anxiety and depression. Ironically, those animals that are likely to be the best models for psychopathology are also likely to be considered the ones that are most morally problematic to use, if it seems probable that (and if indeed they are initially selected as models because) they have experiences that are similar to human experiences that we have strong reasons to avoid causing, and indeed aim to alleviate (such as pain, anxiety or sadness). In this paper, against the background of contemporary discussions in animal ethics and the philosophy of animal minds, we discuss the views that it is morally permissible to use animals in these kinds of experiments, and that it is better to use less cognitively complex animals (such as zebrafish) than more complex animals (such as dogs). First, we criticise some justifications for the claim that human beings and more complex animals have higher moral status. We argue that contemporary approaches that attribute equal moral status to all beings that are capable of conscious strivings strivings (e.g. avoiding pain and anxiety; aiming to eat and play) are based on more plausible assumptions. Second, we argue that it is problematic to assume that less cognitively complex animals have a lesser sensory and emotional experience than more complex beings across the board. In specific cases, there might be good reasons to assume that more complex beings would be harmed more by a specific physical or environmental intervention, but it might also be that they sometimes are harmed less because of a better ability to cope. Determining whether a specific experiment is justified is therefore a complex issue. Our aim in this chapter is to stimulate further reflection on these common assumptions behind the use of animal models for psychopathologies. In

  9. Amphibians as animal models for laboratory research in physiology.

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    Burggren, Warren W; Warburton, Stephen

    2007-01-01

    The concept of animal models is well honored, and amphibians have played a prominent part in the success of using key species to discover new information about all animals. As animal models, amphibians offer several advantages that include a well-understood basic physiology, a taxonomic diversity well suited to comparative studies, tolerance to temperature and oxygen variation, and a greater similarity to humans than many other currently popular animal models. Amphibians now account for approximately 1/4 to 1/3 of lower vertebrate and invertebrate research, and this proportion is especially true in physiological research, as evident from the high profile of amphibians as animal models in Nobel Prize research. Currently, amphibians play prominent roles in research in the physiology of musculoskeletal, cardiovascular, renal, respiratory, reproductive, and sensory systems. Amphibians are also used extensively in physiological studies aimed at generating new insights in evolutionary biology, especially in the investigation of the evolution of air breathing and terrestriality. Environmental physiology also utilizes amphibians, ranging from studies of cryoprotectants for tissue preservation to physiological reactions to hypergravity and space exploration. Amphibians are also playing a key role in studies of environmental endocrine disruptors that are having disproportionately large effects on amphibian populations and where specific species can serve as sentinel species for environmental pollution. Finally, amphibian genera such as Xenopus, a genus relatively well understood metabolically and physiologically, will continue to contribute increasingly in this new era of systems biology and "X-omics."

  10. Engineering Large Animal Species to Model Human Diseases.

    Science.gov (United States)

    Rogers, Christopher S

    2016-07-01

    Animal models are an important resource for studying human diseases. Genetically engineered mice are the most commonly used species and have made significant contributions to our understanding of basic biology, disease mechanisms, and drug development. However, they often fail to recreate important aspects of human diseases and thus can have limited utility as translational research tools. Developing disease models in species more similar to humans may provide a better setting in which to study disease pathogenesis and test new treatments. This unit provides an overview of the history of genetically engineered large animals and the techniques that have made their development possible. Factors to consider when planning a large animal model, including choice of species, type of modification and methodology, characterization, production methods, and regulatory compliance, are also covered. © 2016 by John Wiley & Sons, Inc. Copyright © 2016 John Wiley & Sons, Inc.

  11. Dynamic modeling of lung tumor motion during respiration

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    Kyriakou, E; McKenzie, D R, E-mail: e.kyriakou@physics.usyd.edu.au, E-mail: d.mckenzie@physics.usyd.edu.au [School of Physics, University of Sydney, NSW 2006 (Australia)

    2011-05-21

    A dynamic finite element model of the lung that incorporates a simplified geometry with realistic lung material properties has been developed. Observations of lung motion from respiratory-gated computed tomography were used to provide a database against which the predictions of the model are assessed. Data from six patients presenting with lung tumors were processed to give sagittal sections of the lung containing the tumor as a function of the breathing phase. Statistical shape modeling was used to outline the diaphragm, the tumor volume and the thoracic wall at each breathing phase. The motion of the tumor in the superior-inferior direction was plotted against the diaphragm displacement. The finite element model employed a simplified geometry in which the lung material fills a rectangular volume enabling two-dimensional coordinates to be used. The diaphragm is represented as a piston, driving the motion. Plots of lung displacement against diaphragm displacement form hysteresis loops that are a sensitive indicator of the characteristics of the motion. The key parameters of lung material that determine the motion are the density and elastic properties of lung material and the airway permeability. The model predictions of the hysteresis behavior agreed well with observation only when lung material is modeled as viscoelastic. The key material parameters are suggested for use as prognostic indicators of the progression of disease and of changes arising from the response of the lung to radiation treatment.

  12. Alternative animal model for studies of total skin thickness burns.

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    Andrade, Ana Laura Martins de; Parisi, Julia Risso; Brassolatti, Patrícia; Parizotto, Nivaldo Antonio

    2017-10-01

    To present an alternative experimental model of third degree burn of easy reproducibility. Eighteen male Wister rats were randomly divided into three groups, 6 of which were allocated to each group. A soldering iron coupled to an aluminum plate was used to produce burn, at a temperature of 150ºC, with different exposure times per group. Group 5 (G5) animals were burned at 150°C with exposure time of 5 seconds; Group 10 (G10) the animals were burned at 150°C with exposure time of 10 seconds and group 15 (G15) the animals were burned at 150°C with exposure time of 15 seconds. Histopathological analyzes showed that all three groups had similar morphological characteristics, with total thickness involvement. The technique is effective to reproduce a third degree burn and suggests the temperature of 150ºC with 5 seconds of exposure in order to minimize the risks to the animals.

  13. Animal Models of Diabetic Retinopathy: Summary and Comparison

    Science.gov (United States)

    Lo, Amy C. Y.

    2013-01-01

    Diabetic retinopathy (DR) is a microvascular complication associated with chronic exposure to hyperglycemia and is a major cause of blindness worldwide. Although clinical assessment and retinal autopsy of diabetic patients provide information on the features and progression of DR, its underlying pathophysiological mechanism cannot be deduced. In order to have a better understanding of the development of DR at the molecular and cellular levels, a variety of animal models have been developed. They include pharmacological induction of hyperglycemia and spontaneous diabetic rodents as well as models of angiogenesis without diabetes (to compensate for the absence of proliferative DR symptoms). In this review, we summarize the existing protocols to induce diabetes using STZ. We also describe and compare the pathological presentations, in both morphological and functional aspects, of the currently available DR animal models. The advantages and disadvantages of using different animals, ranging from zebrafish, rodents to other higher-order mammals, are also discussed. Until now, there is no single model that displays all the clinical features of DR as seen in human. Yet, with the understanding of the pathological findings in these animal models, researchers can select the most suitable models for mechanistic studies or drug screening. PMID:24286086

  14. Animal models of disc degeneration and major genetic strategies.

    Science.gov (United States)

    Sun, Fu; Qu, Ji-Ning; Zhang, Yin-Gang

    2013-01-01

    The establishment of a reliable animal model of lumbar disc degeneration (AMDD) is important for studying pathogenesis and evaluating treatment effectiveness. However, an ideal AMDD for use in laboratory studies has not yet been produced. This retrospective study reviews and compares several common AMDD and discusses their strengths and weaknesses. We also suggest a new method for establishing future AMDD. The identified genes associated with disc degeneration are susceptibility genes, which elevate risk but do not necessarily lead to disease occurrence. We propose to identify families with hereditary disc degeneration, find major casual genes with exome sequencing, and establish transgenic animal models. This approach may help us to build an improved AMDD.

  15. Simple models for studying complex spatiotemporal patterns of animal behavior

    Science.gov (United States)

    Tyutyunov, Yuri V.; Titova, Lyudmila I.

    2017-06-01

    Minimal mathematical models able to explain complex patterns of animal behavior are essential parts of simulation systems describing large-scale spatiotemporal dynamics of trophic communities, particularly those with wide-ranging species, such as occur in pelagic environments. We present results obtained with three different modelling approaches: (i) an individual-based model of animal spatial behavior; (ii) a continuous taxis-diffusion-reaction system of partial-difference equations; (iii) a 'hybrid' approach combining the individual-based algorithm of organism movements with explicit description of decay and diffusion of the movement stimuli. Though the models are based on extremely simple rules, they all allow description of spatial movements of animals in a predator-prey system within a closed habitat, reproducing some typical patterns of the pursuit-evasion behavior observed in natural populations. In all three models, at each spatial position the animal movements are determined by local conditions only, so the pattern of collective behavior emerges due to self-organization. The movement velocities of animals are proportional to the density gradients of specific cues emitted by individuals of the antagonistic species (pheromones, exometabolites or mechanical waves of the media, e.g., sound). These cues play a role of taxis stimuli: prey attract predators, while predators repel prey. Depending on the nature and the properties of the movement stimulus we propose using either a simplified individual-based model, a continuous taxis pursuit-evasion system, or a little more detailed 'hybrid' approach that combines simulation of the individual movements with the continuous model describing diffusion and decay of the stimuli in an explicit way. These can be used to improve movement models for many species, including large marine predators.

  16. The enduring importance of animal models in understanding periodontal disease.

    Science.gov (United States)

    Hajishengallis, George; Lamont, Richard J; Graves, Dana T

    2015-01-01

    Whereas no single animal model can reproduce the complexity of periodontitis, different aspects of the disease can be addressed by distinct models. Despite their limitations, animal models are essential for testing the biological significance of in vitro findings and for establishing cause-and-effect relationships relevant to clinical observations, which are typically correlative. We provide evidence that animal-based studies have generated a durable framework for dissecting the mechanistic basis of periodontitis. These studies have solidified the etiologic role of bacteria in initiating the inflammatory response that leads to periodontal bone loss and have identified key mediators (IL-1, TNF, prostaglandins, complement, RANKL) that induce inflammatory breakdown. Moreover, animal studies suggest that dysbiosis, rather than individual bacterial species, are important in initiating periodontal bone loss and have introduced the concept that organisms previously considered commensals can play important roles as accessory pathogens or pathobionts. These studies have also provided insight as to how systemic conditions, such as diabetes or leukocyte adhesion deficiency, contribute to tissue destruction. In addition, animal studies have identified and been useful in testing therapeutic targets.

  17. Cardiovascular Imaging: What Have We Learned From Animal Models?

    Directory of Open Access Journals (Sweden)

    Arnoldo eSantos

    2015-10-01

    Full Text Available Cardiovascular imaging has become an indispensable tool for patient diagnosis and follow up. Probably the wide clinical applications of imaging are due to the possibility of a detailed and high quality description and quantification of cardiovascular system structure and function. Also phenomena that involve complex physiological mechanisms and biochemical pathways, such as inflammation and ischemia, can be visualized in a nondestructive way. The widespread use and evolution of imaging would not have been possible without animal studies. Animal models have allowed for instance, i the technical development of different imaging tools, ii to test hypothesis generated from human studies and finally, iii to evaluate the translational relevance assessment of in vitro and ex-vivo results. In this review, we will critically describe the contribution of animal models to the use of biomedical imaging in cardiovascular medicine. We will discuss the characteristics of the most frequent models used in/for imaging studies. We will cover the major findings of animal studies focused in the cardiovascular use of the repeatedly used imaging techniques in clinical practice and experimental studies. We will also describe the physiological findings and/or learning processes for imaging applications coming from models of the most common cardiovascular diseases. In these diseases, imaging research using animals has allowed the study of aspects such as: ventricular size, shape, global function and wall thickening, local myocardial function, myocardial perfusion, metabolism and energetic assessment, infarct quantification, vascular lesion characterization, myocardial fiber structure, and myocardial calcium uptake. Finally we will discuss the limitations and future of imaging research with animal models.

  18. Contemporary Animal Models For Human Gene Therapy Applications.

    Science.gov (United States)

    Gopinath, Chitra; Nathar, Trupti Job; Ghosh, Arkasubhra; Hickstein, Dennis Durand; Nelson, Everette Jacob Remington

    2015-01-01

    Over the past three decades, gene therapy has been making considerable progress as an alternative strategy in the treatment of many diseases. Since 2009, several studies have been reported in humans on the successful treatment of various diseases. Animal models mimicking human disease conditions are very essential at the preclinical stage before embarking on a clinical trial. In gene therapy, for instance, they are useful in the assessment of variables related to the use of viral vectors such as safety, efficacy, dosage and localization of transgene expression. However, choosing a suitable disease-specific model is of paramount importance for successful clinical translation. This review focuses on the animal models that are most commonly used in gene therapy studies, such as murine, canine, non-human primates, rabbits, porcine, and a more recently developed humanized mice. Though small and large animals both have their own pros and cons as disease-specific models, the choice is made largely based on the type and length of study performed. While small animals with a shorter life span could be well-suited for degenerative/aging studies, large animals with longer life span could suit longitudinal studies and also help with dosage adjustments to maximize therapeutic benefit. Recently, humanized mice or mouse-human chimaeras have gained interest in the study of human tissues or cells, thereby providing a more reliable understanding of therapeutic interventions. Thus, animal models are of great importance with regard to testing new vector technologies in vivo for assessing safety and efficacy prior to a gene therapy clinical trial.

  19. Finite Element Modeling of Avascular Tumor Growth Using a Stress-Driven Model.

    Science.gov (United States)

    Iranmanesh, Faezeh; Nazari, Mohammad Ali

    2017-08-01

    Tumor growth being a multistage process has been investigated from different aspects. In the present study, an attempt is made to represent a constitutive-structure-based model of avascular tumor growth in which the effects of tensile stresses caused by collagen fibers are considered. Collagen fibers as a source of anisotropy in the structure of tissue are taken into account using a continuous fiber distribution formulation. To this end, a finite element modeling is implemented in which a neo-Hookean hyperelastic material is assigned to the tumor and its surrounding host. The tumor is supplied with a growth term. The growth term includes the effect of parameters such as nutrient concentration on the tumor growth and the tumor's solid phase content in the formulation. Results of the study revealed that decrease of solid phase is indicative of decrease in growth rate and the final steady-state value of tumor's radius. Moreover, fiber distribution affects the final shape of the tumor, and it could be used to control the shape and geometry of the tumor in complex morphologies. Finally, the findings demonstrated that the exerted stresses on the tumor increase as time passes. Compression of tumor cells leads to the reduction of tumor growth rate until it gradually reaches an equilibrium radius. This finding is in accordance with experimental data. Hence, this formulation can be deployed to evaluate both the residual stresses induced by growth and the mechanical interactions with the host tissue.

  20. Fluorescence laparoscopy imaging of pancreatic tumor progression in an orthotopic mouse model

    Science.gov (United States)

    Tran Cao, Hop S.; Kaushal, Sharmeela; Lee, Claudia; Snyder, Cynthia S.; Thompson, Kari J.; Horgan, Santiago; Talamini, Mark A.; Hoffman, Robert M.

    2010-01-01

    Background The use of fluorescent proteins to label tumors is revolutionizing cancer research, enabling imaging of both primary and metastatic lesions, which is important for diagnosis, staging, and therapy. This report describes the use of fluorescence laparoscopy to image green fluorescent protein (GFP)-expressing tumors in an orthotopic mouse model of human pancreatic cancer. Methods The orthotopic mouse model of human pancreatic cancer was established by injecting GFP-expressing MiaPaCa-2 human pancreatic cancer cells into the pancreas of 6-week-old female athymic mice. On postoperative day 14, diagnostic laparoscopy using both white and fluorescent light was performed. A standard laparoscopic system was modified by placing a 480-nm short-pass excitation filter between the light cable and the laparoscope in addition to using a 2-mm-thick emission filter. A camera was used that allowed variable exposure time and gain setting. For mouse laparoscopy, a 3-mm 0° laparoscope was used. The mouse’s abdomen was gently insufflated to 2 mm Hg via a 22-gauge angiocatheter. After laparoscopy, the animals were sacrificed, and the tumors were collected and processed for histologic review. The experiments were performed in triplicate. Results Fluorescence laparoscopy enabled rapid imaging of the brightly fluorescent tumor in the pancreatic body. Use of the proper filters enabled simultaneous visualization of the tumor and the surrounding structures with minimal autofluorescence. Fluorescence laparoscopy thus allowed exact localization of the tumor, eliminating the need to switch back and forth between white and fluorescence lighting, under which the background usually is so darkened that it is difficult to maintain spatial orientation. Conclusion The use of fluorescence laparoscopy permits the facile, real-time imaging and localization of tumors labeled with fluorescent proteins. The results described in this report should have important clinical potential. PMID:20533064

  1. Animal models for implant biomaterial research in bone: A review

    Directory of Open Access Journals (Sweden)

    A I Pearce

    2007-03-01

    Full Text Available Development of an optimal interface between bone and orthopaedic and dental implants has taken place for many years. In order to determine whether a newly developed implant material conforms to the requirements of biocompatibility, mechanical stability and safety, it must undergo rigorous testing both in vitro and in vivo. Results from in vitro studies can be difficult to extrapolate to the in vivo situation. For this reason the use of animal models is often an essential step in the testing of orthopaedic and dental implants prior to clinical use in humans. This review discusses some of the more commonly available and frequently used animal models such as the dog, sheep, goat, pig and rabbit models for the evaluation of bone-implant interactions. Factors for consideration when choosing an animal model and implant design are discussed. Various bone specific features are discussed including the usage of the species, bone macrostructure and microstructure and bone composition and remodelling, with emphasis being placed on the similarity between the animal model and the human clinical situation. While the rabbit was the most commonly used of the species discussed in this review, it is clear that this species showed the least similarities to human bone. There were only minor differences in bone composition between the various species and humans. The pig demonstrated a good likeness with human bone however difficulties may be encountered in relation to their size and ease of handling. In this respect the dog and sheep/goat show more promise as animal models for the testing of bone implant materials. While no species fulfils all of the requirements of an ideal model, an understanding of the differences in bone architecture and remodelling between the species is likely to assist in the selection of a suitable species for a defined research question.

  2. Social defeat models in animal science: What we have learned from rodent models.

    Science.gov (United States)

    Toyoda, Atsushi

    2017-07-01

    Studies on stress and its impacts on animals are very important in many fields of science, including animal science, because various stresses influence animal production and animal welfare. In particular, the social stresses within animal groups have profound impact on animals, with the potential to induce abnormal behaviors and health problems. In humans, social stress induces several health problems, including psychiatric disorders. In animal stress models, social defeat models are well characterized and used in various research fields, particularly in studies concerning mental disorders. Recently, we have focused on behavior, nutrition and metabolism in rodent models of social defeat to elucidate how social stresses affect animals. In this review, recent significant progress in studies related to animal social defeat models are described. In the field of animal science, these stress models may contribute to advances in the development of functional foods and in the management of animal welfare. © 2017 The Authors. Animal Science Journal published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Animal Science.

  3. A systematic review of current osteoporotic metaphyseal fracture animal models.

    Science.gov (United States)

    Wong, R M Y; Choy, M H V; Li, M C M; Leung, K-S; K-H Chow, S; Cheung, W-H; Cheng, J C Y

    2018-01-01

    The treatment of osteoporotic fractures is a major challenge, and the enhancement of healing is critical as a major goal in modern fracture management. Most osteoporotic fractures occur at the metaphyseal bone region but few models exist and the healing is still poorly understood. A systematic review was conducted to identify and analyse the appropriateness of current osteoporotic metaphyseal fracture animal models. A literature search was performed on the Pubmed, Embase, and Web of Science databases, and relevant articles were selected. A total of 19 studies were included. Information on the animal, induction of osteoporosis, fracture technique, site and fixation, healing results, and utility of the model were extracted. Fracture techniques included drill hole defects (3 of 19), bone defects (3 of 19), partial osteotomy (1 of 19), and complete osteotomies (12 of 19). Drill hole models and incomplete osteotomy models are easy to perform and allow the study of therapeutic agents but do not represent the usual clinical setting. Additionally, biomaterials can be filled into drill hole defects for analysis. Complete osteotomy models are most commonly used and are best suited for the investigation of therapeutic drugs or noninvasive interventions. The metaphyseal defect models allow the study of biomaterials, which are associated with complex and comminuted osteoporotic fractures. For a clinically relevant model, we propose that an animal model should satisfy the following criteria to study osteoporotic fracture healing: 1) induction of osteoporosis, 2) complete osteotomy or defect at the metaphysis unilaterally, and 3) internal fixation. Cite this article : R. M. Y. Wong, M. H. V. Choy, M. C. M. Li, K-S. Leung, S. K-H. Chow, W-H. Cheung, J. C. Y. Cheng. A systematic review of current osteoporotic metaphyseal fracture animal models. Bone Joint Res 2018;7:6-11. DOI: 10.1302/2046-3758.71.BJR-2016-0334.R2. © 2018 Wong et al.

  4. Overview on available animal models for application in leukemia research

    International Nuclear Information System (INIS)

    Borkhardt, A.; Sanchez-Garcia, I.; Cobaleda, C.; Hauer, J.

    2015-01-01

    The term ''leukemia'' encompasses a group of diseases with a variable clinical and pathological presentation. Its cellular origin, its biology and the underlying molecular genetic alterations determine the very variable and individual disease phenotype. The focus of this review is to discuss the most important guidelines to be taken into account when we aim at developing an ''ideal'' animal model to study leukemia. The animal model should mimic all the clinical, histological and molecular genetic characteristics of the human phenotype and should be applicable as a clinically predictive model. It should achieve all the requirements to be used as a standardized model adaptive to basic research as well as to pharmaceutical practice. Furthermore it should fulfill all the criteria to investigate environmental risk factors, the role of genomic mutations and be applicable for therapeutic testing. These constraints limit the usefulness of some existing animal models, which are however very valuable for basic research. Hence in this review we will primarily focus on genetically engineered mouse models (GEMMs) to study the most frequent types of childhood leukemia. GEMMs are robust models with relatively low site specific variability and which can, with the help of the latest gene modulating tools be adapted to individual clinical and research questions. Moreover they offer the possibility to restrict oncogene expression to a defined target population and regulate its expression level as well as its timely activity. Until recently it was only possible in individual cases to develop a murin model, which fulfills the above mentioned requirements. Hence the development of new regulatory elements to control targeted oncogene expression should be priority. Tightly controlled and cell specific oncogene expression can then be combined with a knock-in approach and will depict a robust murine model, which enables almost physiologic oncogene

  5. Principles for developing animal models of military PTSD

    Directory of Open Access Journals (Sweden)

    Nikolaos P. Daskalakis

    2014-08-01

    Full Text Available The extent to which animal studies can be relevant to military posttraumatic stress disorder (PTSD continues to be a matter of discussion. Some features of the clinical syndrome are more easily modeled than others. In the animal literature, a great deal of attention is focused on modeling the characteristics of military exposures and their impact on measurable behaviors and biological parameters. There are many issues to consider regarding the ecological validity of predator, social defeat or immobilization stress to combat-related experience. In contrast, less attention has been paid to individual variation following these exposures. Such variation is critical to understand how individual differences in the response to military trauma exposure may result to PTSD or resilience. It is important to consider potential differences in biological findings when comparing extremely exposed to non-exposed animals, versus those that result from examining individual differences. Animal models of military PTSD are also critical in advancing efforts in clinical treatment. In an ideal translational approach to study deployment related outcomes, information from humans and animals, blood and brain, should be carefully considered in tandem, possibly even computed simultaneously, to identify molecules, pathways and networks that are likely to be the key drivers of military PTSD symptoms. With the use novel biological methodologies (e.g., optogenetics in the animal models, critical genes and pathways can be tuned up or down (rather than over-expressed or ablated completely in discrete brain regions. Such techniques together with pre-and post-deployment human imaging will accelerate the identification of novel pharmacological and non-pharmacological intervention strategies.

  6. Building Context with Tumor Growth Modeling Projects in Differential Equations

    Science.gov (United States)

    Beier, Julie C.; Gevertz, Jana L.; Howard, Keith E.

    2015-01-01

    The use of modeling projects serves to integrate, reinforce, and extend student knowledge. Here we present two projects related to tumor growth appropriate for a first course in differential equations. They illustrate the use of problem-based learning to reinforce and extend course content via a writing or research experience. Here we discuss…

  7. Concise Review: Stem Cell Trials Using Companion Animal Disease Models.

    Science.gov (United States)

    Hoffman, Andrew M; Dow, Steven W

    2016-07-01

    Studies to evaluate the therapeutic potential of stem cells in humans would benefit from more realistic animal models. In veterinary medicine, companion animals naturally develop many diseases that resemble human conditions, therefore, representing a novel source of preclinical models. To understand how companion animal disease models are being studied for this purpose, we reviewed the literature between 2008 and 2015 for reports on stem cell therapies in dogs and cats, excluding laboratory animals, induced disease models, cancer, and case reports. Disease models included osteoarthritis, intervertebral disc degeneration, dilated cardiomyopathy, inflammatory bowel diseases, Crohn's fistulas, meningoencephalomyelitis (multiple sclerosis-like), keratoconjunctivitis sicca (Sjogren's syndrome-like), atopic dermatitis, and chronic (end-stage) kidney disease. Stem cells evaluated in these studies included mesenchymal stem-stromal cells (MSC, 17/19 trials), olfactory ensheathing cells (OEC, 1 trial), or neural lineage cells derived from bone marrow MSC (1 trial), and 16/19 studies were performed in dogs. The MSC studies (13/17) used adipose tissue-derived MSC from either allogeneic (8/13) or autologous (5/13) sources. The majority of studies were open label, uncontrolled studies. Endpoints and protocols were feasible, and the stem cell therapies were reportedly safe and elicited beneficial patient responses in all but two of the trials. In conclusion, companion animals with naturally occurring diseases analogous to human conditions can be recruited into clinical trials and provide realistic insight into feasibility, safety, and biologic activity of novel stem cell therapies. However, improvements in the rigor of manufacturing, study design, and regulatory compliance will be needed to better utilize these models. Stem Cells 2016;34:1709-1729. © 2016 AlphaMed Press.

  8. Animal Models of Diabetes Mellitus for Islet Transplantation

    Directory of Open Access Journals (Sweden)

    Naoaki Sakata

    2012-01-01

    Full Text Available Due to current improvements in techniques for islet isolation and transplantation and protocols for immunosuppressants, islet transplantation has become an effective treatment for severe diabetes patients. Many diabetic animal models have contributed to such improvements. In this paper, we focus on 3 types of models with different mechanisms for inducing diabetes mellitus (DM: models induced by drugs including streptozotocin (STZ, pancreatomized models, and spontaneous models due to autoimmunity. STZ-induced diabetes is one of the most commonly used experimental diabetic models and is employed using many specimens including rodents, pigs or monkeys. The management of STZ models is well established for islet studies. Pancreatomized models reveal different aspects compared to STZ-induced models in terms of loss of function in the increase and decrease of blood glucose and therefore are useful for evaluating the condition in total pancreatomized patients. Spontaneous models are useful for preclinical studies including the assessment of immunosuppressants because such models involve the same mechanisms as type 1 DM in the clinical setting. In conclusion, islet researchers should select suitable diabetic animal models according to the aim of the study.

  9. Animation Augmented Reality Book Model (AAR Book Model) to Enhance Teamwork

    Science.gov (United States)

    Chujitarom, Wannaporn; Piriyasurawong, Pallop

    2017-01-01

    This study aims to synthesize an Animation Augmented Reality Book Model (AAR Book Model) to enhance teamwork and to assess the AAR Book Model to enhance teamwork. Samples are five specialists that consist of one animation specialist, two communication and information technology specialists, and two teaching model design specialists, selected by…

  10. Geospatial forecast model for tsetse-transmitted animal ...

    African Journals Online (AJOL)

    Results indicate that GIS model developed for parasitic diseases based on growing degree day (GDD) concept can be applied to tsetse-transmitted trypanosomosis. GIS for animal trypanosomosis was created using Food and Agriculture Organization – Crop Production System Zones (FAO-CPSZ) database and Normalized ...

  11. Unraveling the genetics of chronic kidney disease using animal models

    NARCIS (Netherlands)

    Korstanje, Ron; DiPetrillo, K.

    2004-01-01

    Identifying genes underlying common forms of kidney disease in humans has proven difficult, expensive, and time consuming. Quantitative trait loci (QTL) for several complex traits are concordant among mice, rats, and humans, suggesting that genetic findings from these animal models are relevant to

  12. In search for animal models of female sexual dysfunction

    NARCIS (Netherlands)

    Snoeren, E.M.S.

    2010-01-01

    Female Sexual Dysfunction (FSD) is a disorder that affects around 40% of the population. Low sexual arousal and low sexual desire are the most common problems. The mechanisms underlying the disorder are still unclear. The aims of this thesis were 1) the search for animal models of FSD, 2) the

  13. Animation Model to Conceptualize ATP Generation: A Mitochondrial Oxidative Phosphorylation

    Science.gov (United States)

    Jena, Ananta Kumar

    2015-01-01

    Adenosine triphosphate (ATP) is the molecular unit of intracellular energy and it is the product of oxidative phosphorylation of cellular respiration uses in cellular processes. The study explores the growth of the misconception levels amongst the learners and evaluates the effectiveness of animation model over traditional methods. The data…

  14. Animal models for plaque rupture: a biomechanical assessment

    NARCIS (Netherlands)

    van der Heiden, Kim; Hoogendoorn, Ayla; Daemen, Mat J.; Gijsen, Frank J. H.

    2016-01-01

    Rupture of atherosclerotic plaques is the main cause of acute cardiovascular events. Animal models of plaque rupture are rare but essential for testing new imaging modalities to enable diagnosis of the patient at risk. Moreover, they enable the design of new treatment strategies to prevent plaque

  15. The miniature pig as an animal model in biomedical research

    Czech Academy of Sciences Publication Activity Database

    Vodička, Petr; Smetana Jr., K.; Dvořánková, B.; Emerick, T.; Xu, Y.; Ourednik, J.; Ourednik, V.; Motlík, Jan

    2005-01-01

    Roč. 1049, - (2005), s. 161-171 ISSN 0077-8923 R&D Projects: GA MŠk(CZ) LN00A065 Institutional research plan: CEZ:AV0Z50450515 Keywords : animal model * stem cell * transgenic pig Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.971, year: 2005

  16. Genetic Evaluation and Ranking of Different Animal Models Using ...

    African Journals Online (AJOL)

    An animal model utilizes all relationships available in a given data set. Estimates for variance components for additive direct, additive maternal, maternal environmental and direct environmental effects, and their covariances between direct and maternal genetic effects for post weaning growth traits have been obtained with ...

  17. Modeling herbivorous animal digestive system as 3- continuous ...

    African Journals Online (AJOL)

    Modeling herbivorous animal digestive system as 3- continuous stirred tank reactor (CSTR) and 1-plug flow reactor (PFR) in series with specific reference to ... This shows the efficiency of each reactor at converting the purely lignocellulosics substrates to useful products like protein, vitamin, fatty acid and the bye-products.

  18. Antimyeloperoxidase-associated proliferative glomerulonephritis: an animal model

    NARCIS (Netherlands)

    Brouwer, E.; Huitema, M. G.; Klok, P. A.; de Weerd, H.; Tervaert, J. W.; Weening, J. J.; Kallenberg, C. G.

    1993-01-01

    To develop an animal model for antimyeloperoxidase (MPO)-associated necrotizing crescentic glomerulonephritis (NCGN), we immunized Brown Norway rats with MPO and localized a neutrophil lysosomal enzyme extract, primarily consisting of MPO and elastinolytic enzymes, plus H2O2, the substrate of MPO,

  19. ANTIMYELOPEROXIDASE-ASSOCIATED PROLIFERATIVE GLOMERULONEPHRITIS - AN ANIMAL-MODEL

    NARCIS (Netherlands)

    BROUWER, E; HUITEMA, MG; KLOK, PA; DEWEERD, H; TERVAERT, JWC; WEENING, JJ; KALLENBERG, CGM

    1993-01-01

    To develop an animal model for antimyeloperoxidase (MPO)-associated necrotizing crescentic glomerulonephritis (NCGN), we immunized Brown Norway rats with MPO and localized a neutrophil lysosomal enzyme extract, primarily consisting of MPO and elastinolytic enzymes, plus H2O2, the substrate of MPO,

  20. Animal models of human respiratory syncytial virus disease

    NARCIS (Netherlands)

    Bem, Reinout A.; Domachowske, Joseph B.; Rosenberg, Helene F.

    2011-01-01

    Infection with the human pneumovirus pathogen, respiratory syncytial virus (hRSV), causes a wide spectrum of respiratory disease, notably among infants and the elderly. Laboratory animal studies permit detailed experimental modeling of hRSV disease and are therefore indispensable in the search for

  1. A review of animal models for portal vein embolization

    NARCIS (Netherlands)

    Huisman, Floor; van Lienden, Krijn P.; Damude, Samantha; Hoekstra, Lisette T.; van Gulik, Thomas M.

    2014-01-01

    Portal vein embolization (PVE) is a preoperative intervention to increase the future remnant liver (FRL) through regeneration of the non-embolized liver lobes. This review assesses all the relevant animal models of PVE available, to guide researchers who intend to study PVE. We performed a

  2. Animal models for arthritis: innovative tools for prevention and treatment

    NARCIS (Netherlands)

    Kollias, G.; Papadaki, P.; Apparailly, F.; Vervoordeldonk, M.J.; Holmdahl, R.; Baumans, V.; Desaintes, C.; Di Santo, J.; Distler, J.; Garside, P.; Hegen, M.; Huizinga, T.W.J.; Jüngel, A.; Klareskog, L.; McInnes, I.; Ragoussis, I.; Schett, G.; Hart, B.t.; Tak, P.P.; Toes, R.; van den Berg, W.; Wurst, W.; Gay, S.

    2011-01-01

    The development of novel treatments for rheumatoid arthritis (RA) requires the interplay between clinical observations and studies in animal models. Given the complex molecular pathogenesis and highly heterogeneous clinical picture of RA, there is an urgent need to dissect its multifactorial nature

  3. Applications of Magnetic Resonance in Model Systems: Tumor Biology and Physiology

    Directory of Open Access Journals (Sweden)

    Robert J. Gillies

    2000-01-01

    Full Text Available A solid tumor presents a unique challenge as a system in which the dynamics of the relationship between vascularization, the physiological environment and metabolism are continually changing with growth and following treatment. Magnetic resonance imaging (MRI and magnetic resonance spectroscopy (MRS studies have demonstrated quantifiable linkages between the physiological environment, angiogenesis, vascularization and metabolism of tumors. The dynamics between these parameters continually change with tumor aggressiveness, tumor growth and during therapy and each of these can be monitored longitudinally, quantitatively and non-invasively with MRI and MRS. An important aspect of MRI and MRS studies is that techniques and findings are easily translated between systems. Hence, pre-clinical studies using cultured cells or experimental animals have a high connectivity to potential clinical utility. In the following review, leaders in the field of MR studies of basic tumor physiology using pre-clinical models have contributed individual sections according to their expertise and outlook. The following review is a cogent and timely overview of the current capabilities and state-of-the-art of MRI and MRS as applied to experimental cancers. A companion review deals with the application of MR methods to anticancer therapy.

  4. Computational Model for Tumor Oxygenation Applied to Clinical Data on Breast Tumor Hemoglobin Concentrations Suggests Vascular Dilatation and Compression.

    Directory of Open Access Journals (Sweden)

    Michael Welter

    Full Text Available We present a computational model for trans-vascular oxygen transport in synthetic tumor and host tissue blood vessel networks, aiming at qualitatively explaining published data of optical mammography, which were obtained from 87 breast cancer patients. The data generally show average hemoglobin concentration to be higher in tumors versus host tissue whereas average oxy-to total hemoglobin concentration (vascular segment RBC-volume-weighted blood oxygenation can be above or below normal. Starting from a synthetic arterio-venous initial network the tumor vasculature was generated by processes involving cooption, angiogenesis, and vessel regression. Calculations of spatially resolved blood flow, hematocrit, oxy- and total hemoglobin concentrations, blood and tissue oxygenation were carried out for ninety tumor and associated normal vessel networks starting from various assumed geometries of feeding arteries and draining veins. Spatial heterogeneity in the extra-vascular partial oxygen pressure distribution can be related to various tumor compartments characterized by varying capillary densities and blood flow characteristics. The reported higher average hemoglobin concentration of tumors is explained by growth and dilatation of tumor blood vessels. Even assuming sixfold metabolic rate of oxygen consumption in tumorous versus host tissue, the predicted oxygen hemoglobin concentrations are above normal. Such tumors are likely associated with high tumor blood flow caused by high-caliber blood vessels crossing the tumor volume and hence oxygen supply exceeding oxygen demand. Tumor oxy- to total hemoglobin concentration below normal could only be achieved by reducing tumor vessel radii during growth by a randomly selected factor, simulating compression caused by intra-tumoral solid stress due to proliferation of cells and extracellular matrix. Since compression of blood vessels will impede chemotherapy we conclude that tumors with oxy- to total

  5. 75 FR 54349 - Animal Models-Essential Elements To Address Efficacy Under the Animal Rule; Notice of Public...

    Science.gov (United States)

    2010-09-07

    ... the Animal Rule; Notice of Public Meeting; and Reopening of Comment Period AGENCY: Food and Drug... challenges as addressed in the draft document entitled ``Guidance for ] Industry: Animal Models--Essential Elements to Address Efficacy Under the Animal Rule'' dated January 2009 (Draft Guidance), and as related to...

  6. In Vivo Measurements of Tumor Metabolism and Growth after Administration of Enzastaurin Using Small Animal FDG Positron Emission Tomography

    Directory of Open Access Journals (Sweden)

    Karen E. Pollok

    2009-01-01

    Full Text Available Background. The use of 2-[18F]fluoro-2-deoxy-D-glucose ([18F]FDG may help to establish the antitumor activity of enzastaurin, a novel protein kinase C-beta II (PKC-II inhibitor, in mouse xenografts. Methods. The hematologic cell line RAJI and the solid tumor cell line U87MG were each implanted in NOD/SCID mice. Standard tumor growth measurements and [18F]FDG PET imaging were performed weekly for up to three weeks after tumor implantation and growth. Results. Concomitant with caliper measurements, [18F]FDG PET imaging was performed to monitor glucose metabolism. Heterogeneity of glucose uptake in various areas of the tumors was observed after vehicle or enzastaurin treatment. This heterogeneity may limit the use of [18F]FDG PET imaging to measure enzastaurin-associated changes in xenograft tumors. Conclusion. [18F]FDG PET imaging technique does not correlate with standard caliper assessments in xenografts to assess the antitumor activity of enzastaurin. Future studies are needed to determine the use of [18F]FDG PET imaging in preclinical models.

  7. Fluctuation of Parameters in Tumor Cell Growth Model

    Science.gov (United States)

    Ai, Bao-Quan; Wang, Xian-Ju; Liu, Guo-Tao; Liu, Liang-Gang

    2003-07-01

    We study the steady state properties of a logistic growth model in the presence of Gaussian white noise. Based on the corresponding Fokker-Planck equation the steady state solution of the probability distribution function and its extrema have been investigated. It is found that the fluctuation of the tumor birth rate reduces the population of the cells while the fluctuation of predation rate can prevent the population of tumor cells from going into extinction. Noise in the system can induce the phase transition. The project supported by National Natural Science Foundation of China under Grant No. 10275099 and Natural Science Foundation of Guangdong Province of China under Grant Nos. 021707 and 001182

  8. An Experimental Animal Model for Abdominal Fascia Healing after Surgery

    DEFF Research Database (Denmark)

    Burcharth, J; Pommergaard, H-C; Klein, M

    2013-01-01

    Background: Incisional hernia (IH) is a well-known complication after abdominal surgical procedures. The exact etiology of IH is still unknown even though many risk factors have been suggested. The aim of this study was to create an animal model of a weakly healed abdominal fascia that could...... be used to evaluate the actively healing fascia. Such an animal model may promote future research in the prevention of IH. Methods: 86 male Sprague-Dawley rats were used to establish a model involving six experiments (experiments A-F). Mechanical testing of the breaking strength of the healed fascia...... was performed by testing tissue strips from the healed fascia versus the unincised control fascia 7 and 28 days postoperatively. Results: During the six experiments a healing model was created that produced significantly weaker coherent fascia when compared with the control tissue measured in terms...

  9. Tumor mouse model confirms MAGE-A3 cancer immunotherapeutic as an efficient inducer of long-lasting anti-tumoral responses.

    Directory of Open Access Journals (Sweden)

    Catherine Gérard

    Full Text Available MAGE-A3 is a potential target for immunotherapy due to its tumor-specific nature and expression in several tumor types. Clinical data on MAGE-A3 immunotherapy have raised many questions that can only be addressed by using animal models. In the present study, different aspects of the murine anti-tumor immune responses induced by a recombinant MAGE-A3 protein (recMAGE-A3 in combination with different immunostimulants (AS01, AS02, CpG7909 or AS15 were investigated.Based on cytokine profile analyses and protection against challenge with MAGE-A3-expressing tumor, the combination recMAGE-A3+AS15 was selected for further experimental work, in particular to study the mechanisms of anti-tumor responses. By using MHC class I-, MHC class II-, perforin-, B-cell- and IFN-γ- knock-out mice and CD4+ T cell-, CD8+ T cell- and NK cell- depleted mice, we demonstrated that CD4+ T cells and NK cells are the main anti-tumor effectors, and that IFN-γ is a major effector molecule. This mouse tumor model also established the need to repeat recMAGE-A3+AS15 injections to sustain efficient anti-tumor responses. Furthermore, our results indicated that the efficacy of tumor rejection by the elicited anti-MAGE-A3 responses depends on the proportion of tumor cells expressing MAGE-A3.The recMAGE-A3+AS15 cancer immunotherapy efficiently induced an antigen-specific, functional and long-lasting immune response able to recognize and eliminate MAGE-A3-expressing tumor cells up to several months after the last immunization in mice. The data highlighted the importance of the immunostimulant to induce a Th1-type immune response, as well as the key role played by IFN-γ, CD4+ T cells and NK cells in the anti-tumoral effect.

  10. Orthotopic animal model of pseudomyxoma peritonei: An in vivo model to test anti-angiogenic drug effects.

    Science.gov (United States)

    Dohan, Anthony; Lousquy, Ruben; Eveno, Clarisse; Goere, Diane; Broqueres-You, Dong; Kaci, Rachid; Lehmann-Che, Jacqueline; Launay, Jean-Marie; Soyer, Philippe; Bonnin, Philippe; Pocard, Marc

    2014-07-01

    Pseudomyxoma peritonei (PMP) is an uncommon peritoneal mucinous carcinomatosis confined to the peritoneal cavity. The rarity of PMP in humans makes evaluation of the disease biological features and new therapeutic strategies difficult. Accordingly, there is a need for animal models of PMP. Human PMP tissue was i.p. grafted and grown into nude mice, then constituted into reliable and reproducible orthotopic models. Histological and immunostaining analysis was performed. Bevacizumab was injected twice a week either during tumor growth or after cytoreductive surgery. In vivo imaging of tumor angiogenesis was performed using barium sulfate or isolectin microangiography and Doppler ultrasonography of the superior mesenteric artery. Tumor angiogenesis was confirmed by the presence of tortuous vascular networks with high levels of expression of CD31, vascular endothelial cadherin, and desmin. Doppler ultrasonography of the superior mesenteric artery revealed a twofold increase in blood flow velocity compared with tumor-free mice (P preclinical studies, the efficacy of new therapeutic strategies and anti-angiogenic therapies. Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  11. Targeted hyperthermia after selective embolization with ferromagnetic nanoparticles in a VX2 rabbit liver tumor model

    Directory of Open Access Journals (Sweden)

    Sun HL

    2013-10-01

    Full Text Available Hongliang Sun,1 Linfeng Xu,1 Tianyuan Fan,2 Hongzhi Zhan,3 Xiaodong Wang,3 Yanfei Zhou,2 Ren-jie Yang3 1Department of Interventional Therapy, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou, 2Pharmacy School of Beijing University, Beijing, 3Department of Interventional Therapy, Peking University School of Oncology, Beijing Cancer Hospital and Institute, Beijing, People's Republic of China Background: The purpose of this study was to observe the effect and feasibility of hyperthermia and the influence of heat on surrounding organs in a VX2 rabbit liver model exposed to an alternating magnetic field after embolization with ferromagnetic nanoparticles. Methods: Forty rabbits containing implanted hepatic VX2 carcinomas were divided into four groups, each containing ten rabbits. Fourteen days after tumor transplantation, we opened the abdomen to observe the size and shape of the tumor. A transfemoral retrograde approach was then used for hepatic arterial catheterization in groups B, C, and D to perform angiography and embolization. The next day, three rabbits in group B and all rabbits in group D were exposed to an alternating magnetic field, and the temperature was recorded simultaneously in the center of the tumor, at the edge of the tumor, and in the normal liver parenchyma. On day 28, all animals was euthanized to observe changes in the implanted liver tumor and the condition of the abdomen. A pathologic examination was also done. Results: Before surgery, there was no significant difference in tumor volume between the four groups. Three different temperature points (center of the tumor, edge of the tumor, and in the normal liver parenchyma of group B under an alternating magnetic field were 37.2°C ± 1.1°C, 36.8°C ± 1.2°C, and 36.9°C ± 2.1°C, none of which were significantly different from pretreatment values. Three points basal temperature in group D showed no significant difference (F = 1.038, P = 0.413. Seven to 26

  12. Freshwater Planarians as an Alternative Animal Model for Neurotoxicology.

    Science.gov (United States)

    Hagstrom, Danielle; Cochet-Escartin, Olivier; Zhang, Siqi; Khuu, Cindy; Collins, Eva-Maria S

    2015-09-01

    Traditional toxicology testing has relied on low-throughput, expensive mammalian studies; however, timely testing of the large number of environmental toxicants requires new in vitro and in vivo platforms for inexpensive medium- to high-throughput screening. Herein, we describe the suitability of the asexual freshwater planarian Dugesia japonica as a new animal model for the study of developmental neurotoxicology. As these asexual animals reproduce by binary fission, followed by regeneration of missing body structures within approximately 1 week, development and regeneration occur through similar processes allowing us to induce neurodevelopment "at will" through amputation. This short time scale and the comparable sizes of full and regenerating animals enable parallel experiments in adults and developing worms to determine development-specific aspects of toxicity. Because the planarian brain, despite its simplicity, is structurally and molecularly similar to the mammalian brain, we are able to ascertain neurodevelopmental toxicity that is relevant to humans. As a proof of concept, we developed a 5-step semiautomatic screening platform to characterize the toxicity of 9 known neurotoxicants (consisting of common solvents, pesticides, and detergents) and a neutral agent, glucose, and quantified effects on viability, stimulated and unstimulated behavior, regeneration, and brain structure. Comparisons of our findings with other alternative toxicology animal models, such as zebrafish larvae and nematodes, demonstrated that planarians are comparably sensitive to the tested chemicals. In addition, we found that certain compounds induced adverse effects specifically in developing animals. We thus conclude that planarians offer new complementary opportunities for developmental neurotoxicology animal models. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  13. An animal model of spontaneous metabolic syndrome: Nile grass rat

    OpenAIRE

    Noda, Kousuke; Melhorn, Mark I.; Zandi, Souska; Frimmel, Sonja; Tayyari, Faryan; Hisatomi, Toshio; Almulki, Lama; Pronczuk, Andrzej; Hayes, K. C.; Hafezi-Moghadam, Ali

    2010-01-01

    Metabolic syndrome (MetS) is a prevalent and complex disease, characterized by the variable coexistence of obesity, dyslipidemia, hyperinsulinaemia, and hypertension. The alarming rise in the prevalence of metabolic disorders makes it imperative to innovate preventive or therapeutic measures for MetS and its complications. However, the elucidation of the pathogenesis of MetS has been hampered by the lack of realistic models. For example, the existing animal models of MetS, i.e., genetically e...

  14. Experimental animal model for late postradiation reaction of the colon

    International Nuclear Information System (INIS)

    Trott, K.R.

    1987-01-01

    Experimental animal model worked out in Muenchen is discussed in which late postradiation reaction in Wistar rats following local irradiation of the colon manifests itself by appearance of colonic stenoses causing death of the animal. Clinical symptoms of this reaction together with results of histopathologic examination of the excised parts of the colon localized in the irradiated area are discussed. The relationships effect-dose obtained in this system for X radiation applying different regimen of dose fractionation and different total times of irradiation are presented. 8 refs., 5 figs., 1 tab. (author)

  15. Alternative animal model for studies of total skin thickness burns

    OpenAIRE

    Andrade, Ana Laura Martins de; Parisi, Julia Risso; Brassolatti, Patrícia; Parizotto, Nivaldo Antonio

    2017-01-01

    Abstract Purpose: To present an alternative experimental model of third degree burn of easy reproducibility. Methods: Eighteen male Wister rats were randomly divided into three groups, 6 of which were allocated to each group. A soldering iron coupled to an aluminum plate was used to produce burn, at a temperature of 150ºC, with different exposure times per group. Group 5 (G5) animals were burned at 150°C with exposure time of 5 seconds; Group 10 (G10) the animals were burned at 150°C with e...

  16. Peripheral biomarkers in animal models of major depressive disorder.

    Science.gov (United States)

    Carboni, Lucia

    2013-01-01

    Investigations of preclinical biomarkers for major depressive disorder (MDD) encompass the quantification of proteins, peptides, mRNAs, or small molecules in blood or urine of animal models. Most studies aim at characterising the animal model by including the assessment of analytes or hormones affected in depressive patients. The ultimate objective is to validate the model to better understand the neurobiological basis of MDD. Stress hormones or inflammation-related analytes associated with MDD are frequently measured. In contrast, other investigators evaluate peripheral analytes in preclinical models to translate the results in clinical settings afterwards. Large-scale, hypothesis-free studies are performed in MDD models to identify candidate biomarkers. Other studies wish to propose new targets for drug discovery. Animal models endowed with predictive validity are investigated, and the assessment of peripheral analytes, such as stress hormones or immune molecules, is comprised to increase the confidence in the target. Finally, since the mechanism of action of antidepressants is incompletely understood, studies investigating molecular alterations associated with antidepressant treatment may include peripheral analyte levels. In conclusion, preclinical biomarker studies aid the identification of new candidate analytes to be tested in clinical trials. They also increase our understanding of MDD pathophysiology and help to identify new pharmacological targets.

  17. Malarial birds: modeling infectious human disease in animals.

    Science.gov (United States)

    Slater, Leo B

    2005-01-01

    Through the examination of avian malarias as models of infectious human disease, this paper reveals the kinds of claims that scientists and physicians made on the basis of animal models-biological systems in the laboratory and the field-and what characteristics made for congruence between these models and human malaria. The focus is on the period between 1895 and 1945, and on the genesis and trajectory of certain animal models of malaria within specific locations, such as the Johns Hopkins School of Hygiene and Public Health in Baltimore and Bayer (I. G. Farben) in Elberfeld. These exemplars illustrate a diversity of approaches to malaria-as-disease, and the difficulties of framing aspects of this disease complex within an animal or laboratory system. The diversity and nearness to wild types of the birds, protozoan parasites, and mosquitoes that made up these malaria models contributed a great deal to the complexity of the models. Avian malarias, adopted with enthusiasm, were essential to the success of the U.S. antimalarial program during World War II.

  18. Modelling animal waste pathogen transport from agricultural land to streams

    International Nuclear Information System (INIS)

    Pandey, Pramod K; Soupir, Michelle L; Ikenberry, Charles

    2014-01-01

    The transport of animal waste pathogens from crop land to streams can potentially elevate pathogen levels in stream water. Applying animal manure into crop land as fertilizers is a common practice in developing as well as in developed countries. Manure application into the crop land, however, can cause potential human health. To control pathogen levels in ambient water bodies such as streams, improving our understanding of pathogen transport at farm scale as well as at watershed scale is required. To understand the impacts of crop land receiving animal waste as fertilizers on stream's pathogen levels, here we investigate pathogen indicator transport at watershed scale. We exploited watershed scale hydrological model to estimate the transport of pathogens from the crop land to streams. Pathogen indicator levels (i.e., E. coli levels) in the stream water were predicted. With certain assumptions, model results are reasonable. This study can be used as guidelines for developing the models for calculating the impacts of crop land's animal manure on stream water

  19. Animal models of enterovirus 71 infection: applications and limitations

    Science.gov (United States)

    2014-01-01

    Human enterovirus 71 (EV71) has emerged as a neuroinvasive virus that is responsible for several outbreaks in the Asia-Pacific region over the past 15 years. Appropriate animal models are needed to understand EV71 neuropathogenesis better and to facilitate the development of effective vaccines and drugs. Non-human primate models have been used to characterize and evaluate the neurovirulence of EV71 after the early outbreaks in late 1990s. However, these models were not suitable for assessing the neurovirulence level of the virus and were associated with ethical and economic difficulties in terms of broad application. Several strategies have been applied to develop mouse models of EV71 infection, including strategies that employ virus adaption and immunodeficient hosts. Although these mouse models do not closely mimic human disease, they have been applied to determine the pathogenesis of and treatment and prevention of the disease. EV71 receptor-transgenic mouse models have recently been developed and have significantly advanced our understanding of the biological features of the virus and the host-parasite interactions. Overall, each of these models has advantages and disadvantages, and these models are differentially suited for studies of EV71 pathogenesis and/or the pre-clinical testing of antiviral drugs and vaccines. In this paper, we review the characteristics, applications and limitation of these EV71 animal models, including non-human primate and mouse models. PMID:24742252

  20. Raloxifene inhibits tumor growth and lymph node metastasis in a xenograft model of metastatic mammary cancer

    Directory of Open Access Journals (Sweden)

    Li Zhong-Lian

    2010-10-01

    Full Text Available Abstract Background The effects of raloxifene, a novel selective estrogen receptor modulator, were studied in a mouse metastatic mammary cancer model expressing cytoplasmic ERα. Methods Mammary tumors, induced by inoculation of syngeneic BALB/c mice with BJMC3879luc2 cells, were subsequently treated with raloxifene at 0, 18 and 27 mg/kg/day using mini-osmotic pumps. Results In vitro study demonstrated that the ERα in BJMC3879luc2 cells was smaller (between 50 and 64 kDa than the normal-sized ERα (66 kDa and showed cytoplasmic localization. A statistically significant but weak estradiol response was observed in this cell line. When BJMC3879luc2 tumors were implanted into mice, the ERα mRNA levels were significantly higher in females than in males. In vitro studies showed that raloxifene induced mitochondria-mediated apoptosis and cell-cycle arrest in the G1-phase and a decrease in the cell population in the S-phase. In animal experiments, tumor volumes were significantly suppressed in the raloxifene-treated groups. The multiplicity of lymph node metastasis was significantly decreased in the 27 mg/kg group. Levels of apoptosis were significantly increased in the raloxifene-treated groups, whereas the levels of DNA synthesis were significantly decreased in these groups. No differences in microvessel density in tumors were observed between the control and raloxifene-treated groups. The numbers of dilated lymphatic vessels containing intraluminal tumor cells were significantly reduced in mammary tumors in the raloxifene-treated groups. The levels of ERα mRNA in mammary tumors tended to be decreased in the raloxifene-treated groups. Conclusion These results suggest that the antimetastatic activity of raloxifene in mammary cancer expressing cytoplasmic ERα may be a crucial finding with clinical applications and that raloxifene may be useful as an adjuvant therapy and for the chemoprevention of breast cancer development.

  1. Animal models for Ebola and Marburg virus infections

    Science.gov (United States)

    Nakayama, Eri; Saijo, Masayuki

    2013-01-01

    Ebola and Marburg hemorrhagic fevers (EHF and MHF) are caused by the Filoviridae family, Ebolavirus and Marburgvirus (ebolavirus and marburgvirus), respectively. These severe diseases have high mortality rates in humans. Although EHF and MHF are endemic to sub-Saharan Africa. A novel filovirus, Lloviu virus, which is genetically distinct from ebolavirus and marburgvirus, was recently discovered in Spain where filoviral hemorrhagic fever had never been reported. The virulence of this virus has not been determined. Ebolavirus and marburgvirus are classified as biosafety level-4 (BSL-4) pathogens and Category A agents, for which the US government requires preparedness in case of bioterrorism. Therefore, preventive measures against these viral hemorrhagic fevers should be prepared, not only in disease-endemic regions, but also in disease-free countries. Diagnostics, vaccines, and therapeutics need to be developed, and therefore the establishment of animal models for EHF and MHF is invaluable. Several animal models have been developed for EHF and MHF using non-human primates (NHPs) and rodents, which are crucial to understand pathophysiology and to develop diagnostics, vaccines, and therapeutics. Rhesus and cynomolgus macaques are representative models of filovirus infection as they exhibit remarkably similar symptoms to those observed in humans. However, the NHP models have practical and ethical problems that limit their experimental use. Furthermore, there are no inbred and genetically manipulated strains of NHP. Rodent models such as mouse, guinea pig, and hamster, have also been developed. However, these rodent models require adaptation of the virus to produce lethal disease and do not mirror all symptoms of human filovirus infection. This review article provides an outline of the clinical features of EHF and MHF in animals, including humans, and discusses how the animal models have been developed to study pathophysiology, vaccines, and therapeutics. PMID:24046765

  2. Animal models for Ebola and Marburg virus infections

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    Eri eNakayama

    2013-09-01

    Full Text Available Ebola and Marburg hemorrhagic fevers (EHF and MHF are caused by the Filoviridae family, Ebolavirus and Marburgvirus (ebolavirus and marburgvirus, respectively. These severe diseases have high mortality rates in humans. Although EHF and MHF are endemic to sub-Saharan Africa. A novel filovirus, Lloviu virus, which is genetically distinct from ebolavirus and marburgvirus, was recently discovered in Spain where filoviral hemorrhagic fever had never been reported. The virulence of this virus has not been determined. Ebolavirus and marburgvirus are classified as biosafety level-4 (BSL-4 pathogens and Category A agents, for which the US government requires preparedness in case of bioterrorism. Therefore, preventive measures against these viral hemorrhagic fevers should be prepared, not only in disease-endemic regions, but also in disease-free countries. Diagnostics, vaccines, and therapeutics need to be developed, and therefore the establishment of animal models for EHF and MHF is invaluable. Several animal models have been developed for EHF and MHF using nonhuman primates (NHPs and rodents, which are crucial to understand pathophysiology and to develop diagnostics, vaccines, and therapeutics. Rhesus and cynomolgus macaques are representative models of filovirus infection as they exhibit remarkably similar symptoms to those observed in humans. However, the NHP models have practical and ethical problems that limit their experimental use. Furthermore, there are no inbred and genetically manipulated strains of NHP. Rodent models such as mouse, guinea pig, and hamster, have also been developed. However, these rodent models require adaptation of the virus to produce lethal disease and do not mirror all symptoms of human filovirus infection. This review article provides an outline of the clinical features of EHF and MHF in animals, including humans, and discusses how the animal models have been developed to study pathophysiology, vaccines, and therapeutics.

  3. Role of Cyclooxygenase-2 on Intermittent Hypoxia-Induced Lung Tumor Malignancy in a Mouse Model of Sleep Apnea.

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    Campillo, Noelia; Torres, Marta; Vilaseca, Antoni; Nonaka, Paula Naomi; Gozal, David; Roca-Ferrer, Jordi; Picado, César; Montserrat, Josep Maria; Farré, Ramon; Navajas, Daniel; Almendros, Isaac

    2017-03-16

    An adverse role for obstructive sleep apnea (OSA) in cancer epidemiology and outcomes has recently emerged from clinical and animal studies. In animals, intermittent hypoxia (IH) mimicking OSA promotes tumor malignancy both directly and via host immune alterations. We hypothesized that IH could potentiate cancer aggressiveness through activation of the cyclooxygenase-2 (COX-2) pathway and the concomitant increases in prostaglandin E2 (PGE 2 ). The contribution of the COX-2 in IH-induced enhanced tumor malignancy was assessed using celecoxib as a COX-2 specific inhibitor in a murine model of OSA bearing Lewis lung carcinoma (LLC1) tumors. Exposures to IH accelerated tumor progression with a tumor associated macrophages (TAMs) shift towards a pro-tumoral M2 phenotype. Treatment with celecoxib prevented IH-induced adverse tumor outcomes by inhibiting IH-induced M2 polarization of TAMs. Furthermore, TAMs isolated from IH-exposed mice treated with celecoxib reduced the proliferation of LLC1 naïve cells, while the opposite occurred with placebo-treated IH-exposed mice. Finally, in vitro IH exposures of murine macrophages and LLC1 cells showed that both cell types increased PGE 2 release in response to IH. These results suggest a crucial role for the COX-2 signaling pathway in the IH-exacerbated malignant processes, and designate macrophages and lung adenocarcinoma cells, as potential sources of PGE 2 .

  4. Combined IL-21 and Low-Dose IL-2 therapy induces anti-tumor immunity and long-term curative effects in a murine melanoma tumor model

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    Fox Bernard A

    2006-06-01

    Full Text Available Abstract Background In vivo studies have recently demonstrated that interleukin 21 (IL-21 enhances the anti-tumor function of T-cells and NK cells in murine tumor models, and the combined use of IL-21 and IL-15 has resulted in prolonged tumor regression and survival in mice with previously established tumors. However, the combined anti-tumor effects of IL-21 and low dose IL-2 have not been studied even though IL-2 has been approved for human use, and, at low dose administration, stimulates the proliferation of memory T cells, and does not significantly increase antigen-induced apoptosis or regulatory T cell (Treg expansion. This study examined whether recombinant IL-21 alone or in combination with low-dose IL-2 could improve the in vivo anti-tumor function of naïve, tumor-antigen specific CD8+ T cells in a gp10025–33 T cell receptor transgenic pmel murine melanoma model. Methods Congenic C57BL/6 (Ly5.2 mice bearing subcutaneous B16F10 melanoma tumors were sublethally irradiated to induce lymphopenia. After irradiation naive pmel splenocytes were adoptively transferred, and mice were immunized with bone marrow-derived dendritic cells pulsed with human gp10025–33 (hgp10025–33. Seven days after vaccination groups of mice received 5 consecutive days of intraperitoneal administration of IL-2 alone (20 × 103 IU, IL-21 alone (20 μg or IL-21 and IL-2. Control animals received no cytokine therapy. Results IL-21 alone and IL-2 alone both delayed tumor progression, but only IL-21 significantly augmented long-term survival (20% compared to the control group. However, combination therapy with IL-21 and IL-2 resulted in the highest long-term (>150 days tumor-free survival frequency of 46%. Animals that were tumor-free for > 150 days demonstrated tumor-specific protection after rechallenge with B16F10 melanoma cells. At peak expansion (21 days post vaccination, the combination of IL-21 plus IL-2 resulted in a 2- to 3-fold higher absolute number of

  5. An Animal Model Using Metallic Ions to Produce Autoimmune Nephritis

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    Roxana Ramírez-Sandoval

    2015-01-01

    Full Text Available Autoimmune nephritis triggered by metallic ions was assessed in a Long-Evans rat model. The parameters evaluated included antinuclear autoantibody production, kidney damage mediated by immune complexes detected by immunofluorescence, and renal function tested by retention of nitrogen waste products and proteinuria. To accomplish our goal, the animals were treated with the following ionic metals: HgCl2, CuSO4, AgNO3, and Pb(NO32. A group without ionic metals was used as the control. The results of the present investigation demonstrated that metallic ions triggered antinuclear antibody production in 60% of animals, some of them with anti-DNA specificity. Furthermore, all animals treated with heavy metals developed toxic glomerulonephritis with immune complex deposition along the mesangium and membranes. These phenomena were accompanied by proteinuria and increased concentrations of urea. Based on these results, we conclude that metallic ions may induce experimental autoimmune nephritis.

  6. Transmission of Helicobacter pyori in an animal model.

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    Cellini, L; Marzio, L; Ferrero, G; Del Vino, A; Di Campli, E; Grossi, L; Toracchio, S; Artese, L

    2001-01-01

    An experimental murine model was studied to evaluate the orogastrointestinal colonization of Helicobacter pylori and the animal-to-animal transmission. Balb/C mice were infected with H. pylori and housed with uninoculated mice in cages with and without a grate on the floor. Mice were killed after 7, 14, 30, and 45 days, and samples from the esophagus, stomach, small intestine, colon, and rectum were analyzed for H. pylori by PCR and immunohistochemistry and for histological changes. Bacterial colonization was assessed also by culture from stomach samples. H. pylori was cultured by stomach samples of infected mice at 7, 14, and 30 days. Using PCR and immunohistochemistry, H. pylori was detected in inoculated and uninoculated mice in all areas examined, with an high percentage of positive samples in the esophagus and stomach. Moreover transmission was detected, without differences, regardless of whether mice were housed with or without a grate on the floor, supporting an orooral animal transmission.

  7. Animal models of osteogenesis imperfecta: applications in clinical research

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    Enderli TA

    2016-09-01

    Full Text Available Tanya A Enderli, Stephanie R Burtch, Jara N Templet, Alessandra Carriero Department of Biomedical Engineering, Florida Institute of Technology, Melbourne, FL, USA Abstract: Osteogenesis imperfecta (OI, commonly known as brittle bone disease, is a genetic disease characterized by extreme bone fragility and consequent skeletal deformities. This connective tissue disorder is caused by mutations in the quality and quantity of the collagen that in turn affect the overall mechanical integrity of the bone, increasing its vulnerability to fracture. Animal models of the disease have played a critical role in the understanding of the pathology and causes of OI and in the investigation of a broad range of clinical therapies for the disease. Currently, at least 20 animal models have been officially recognized to represent the phenotype and biochemistry of the 17 different types of OI in humans. These include mice, dogs, and fish. Here, we describe each of the animal models and the type of OI they represent, and present their application in clinical research for treatments of OI, such as drug therapies (ie, bisphosphonates and sclerostin and mechanical (ie, vibrational loading. In the future, different dosages and lengths of treatment need to be further investigated on different animal models of OI using potentially promising treatments, such as cellular and chaperone therapies. A combination of therapies may also offer a viable treatment regime to improve bone quality and reduce fragility in animals before being introduced into clinical trials for OI patients. Keywords: OI, brittle bone, clinical research, mouse, dog, zebrafish

  8. Animal models of transcranial direct current stimulation: Methods and mechanisms.

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    Jackson, Mark P; Rahman, Asif; Lafon, Belen; Kronberg, Gregory; Ling, Doris; Parra, Lucas C; Bikson, Marom

    2016-11-01

    The objective of this review is to summarize the contribution of animal research using direct current stimulation (DCS) to our understanding of the physiological effects of transcranial direct current stimulation (tDCS). We comprehensively address experimental methodology in animal studies, broadly classified as: (1) transcranial stimulation; (2) direct cortical stimulation in vivo and (3) in vitro models. In each case advantages and disadvantages for translational research are discussed including dose translation and the overarching "quasi-uniform" assumption, which underpins translational relevance in all animal models of tDCS. Terminology such as anode, cathode, inward current, outward current, current density, electric field, and uniform are defined. Though we put key animal experiments spanning decades in perspective, our goal is not simply an exhaustive cataloging of relevant animal studies, but rather to put them in context of ongoing efforts to improve tDCS. Cellular targets, including excitatory neuronal somas, dendrites, axons, interneurons, glial cells, and endothelial cells are considered. We emphasize neurons are always depolarized and hyperpolarized such that effects of DCS on neuronal excitability can only be evaluated within subcellular regions of the neuron. Findings from animal studies on the effects of DCS on plasticity (LTP/LTD) and network oscillations are reviewed extensively. Any endogenous phenomena dependent on membrane potential changes are, in theory, susceptible to modulation by DCS. The relevance of morphological changes (galvanotropy) to tDCS is also considered, as we suggest microscopic migration of axon terminals or dendritic spines may be relevant during tDCS. A majority of clinical studies using tDCS employ a simplistic dose strategy where excitability is singularly increased or decreased under the anode and cathode, respectively. We discuss how this strategy, itself based on classic animal studies, cannot account for the

  9. Adoptively transferred human lung tumor specific cytotoxic T cells can control autologous tumor growth and shape tumor phenotype in a SCID mouse xenograft model

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    Ferrone Soldano

    2007-06-01

    Full Text Available Abstract Background The anti-tumor efficacy of human immune effector cells, such as cytolytic T lymphocytes (CTLs, has been difficult to study in lung cancer patients in the clinical setting. Improved experimental models for the study of lung tumor-immune cell interaction as well as for evaluating the efficacy of adoptive transfer of immune effector cells are needed. Methods To address questions related to the in vivo interaction of human lung tumor cells and immune effector cells, we obtained an HLA class I + lung tumor cell line from a fresh surgical specimen, and using the infiltrating immune cells, isolated and characterized tumor antigen-specific, CD8+ CTLs. We then established a SCID mouse-human tumor xenograft model with the tumor cell line and used it to study the function of the autologous CTLs provided via adoptive transfer. Results The tumor antigen specific CTLs isolated from the tumor were found to have an activated memory phenotype and able to kill tumor cells in an antigen specific manner in vitro. Additionally, the tumor antigen-specific CTLs were fully capable of homing to and killing autologous tumors in vivo, and expressing IFN-γ, each in an antigen-dependent manner. A single injection of these CTLs was able to provide significant but temporary control of the growth of autologous tumors in vivo without the need for IL-2. The timing of injection of CTLs played an essential role in the outcome of tumor growth control. Moreover, immunohistochemical analysis of surviving tumor cells following CTL treatment indicated that the surviving tumor cells expressed reduced MHC class I antigens on their surface. Conclusion These studies confirm and extend previous studies and provide additional information regarding the characteristics of CTLs which can be found within a patient's tumor. Moreover, the in vivo model described here provides a unique window for observing events that may also occur in patients undergoing adoptive cellular

  10. Wide-field lifetime-based FRET imaging for the assessment of early functional distribution of transferrin-based delivery in breast tumor-bearing small animals

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    Sinsuebphon, Nattawut; Rudkouskaya, Alena; Barroso, Margarida; Intes, Xavier

    2016-02-01

    Targeted drug delivery is a critical aspect of successful cancer therapy. Assessment of dynamic distribution of the drug provides relative concentration and bioavailability at the target tissue. The most common approach of the assessment is intensity-based imaging, which only provides information about anatomical distribution. Observation of biomolecular interactions can be performed using Förster resonance energy transfer (FRET). Thus, FRET-based imaging can assess functional distribution and provide potential therapeutic outcomes. In this study, we used wide-field lifetime-based FRET imaging for the study of early functional distribution of transferrin delivery in breast cancer tumor models in small animals. Transferrin is a carrier for cancer drug delivery. Its interaction with its receptor is within a few nanometers, which is suitable for FRET. Alexa Fluor® 700 and Alexa Fluor® 750 were conjugated to holo-transferrin which were then administered via tail vein injection to the mice implanted with T47D breast cancer xenografts. Images were continuously acquired for 60 minutes post-injection. The results showed that transferrin was primarily distributed to the liver, the urinary bladder, and the tumor. The cellular uptake of transferrin, which was indicated by the level of FRET, was high in the liver but very low in the urinary bladder. The results also suggested that the fluorescence intensity and FRET signals were independent. The liver showed increasing intensity and increasing FRET during the observation period, while the urinary bladder showed increasing intensity but minimal FRET. Tumors gave varied results corresponding to their FRET progression. These results were relevant to the biomolecular events that occurred in the animals.

  11. Model systems to study immunomodulation in domestic food animals.

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    Roth, J A; Flaming, K P

    1990-01-01

    Development of immunomodulators for use in food producing animals is an active area of research. This research has generally incorporated aspects of immunosuppression in model systems. This methodology is appropriate because most of the research has been aimed at developing immunomodulators for certain economically significant diseases in which immunosuppression is believed to be an important component of their pathogenesis. The primary focus has been on stress-associated diseases (especially bovine respiratory disease), infectious diseases in young animals, and mastitis. The model systems used have limitations, but they have demonstrated that immunomodulators are capable of significantly increasing resistance to these important infectious disease syndromes. As our understanding of molecular immunology increases and as more potential immunomodulators become available, the use of relevant model systems should greatly aid advancement in the field of immunomodulation.

  12. Infantile Spasms: A Critical Review of Emerging Animal Models

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    Stafstrom, Carl E

    2009-01-01

    Infantile spasms is a developmental epilepsy syndrome with unique clinical and EEG features, a specific pattern of pharmacological responsiveness, and poor outcome in terms of cognition and epilepsy. Despite the devastating nature of infantile spasms, little is known about its pathogenesis. Until recently, there has been no animal model available to investigate the pathophysiology of the syndrome or to generate and test novel therapies. Now, several promising animal models have emerged, spanning the etiological spectrum from genetic causes (e.g., Down syndrome or Aristaless-related homeobox [ARX] mutation) to acquired causes (e.g., endogenous and exogenous toxins or stress hormones with convulsant activity or blockade of neural activity). These new models are discussed in this review, with emphasis on the insights each can provide for understanding, treating, and preventing infantile spasms. PMID:19471616

  13. Reproduction of an animal model of landmine blast injuries

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    Sen ZHANG

    2014-03-01

    Full Text Available Objective To reproduce an animal model of landmine blast injuries for studying its mechanism and characteristics. Methods Fifteen healthy New Zealand white rabbits (body weight 1.9-2.4 kg were prepared as experimental animals. Punctiform burster was used to simulate the landmine, and it was electrically detonated far away to produce landmine blast injuries on unilateral hind limb of rabbits in upright state. The vital signs before and 5min, 15min, 30min, 45min, 1h, 2h, 3h, 6h, 9h and 12h after injuries were recorded. Autopsy of dead animals was performed immediately and the survivors were sacrificed for pathological examination 6h and 12h after the injury. Macroscopic and microscopic changes in the injured limb and distant organs were observed. Fifteen random adult body weights were generated by random number table, and the explosive energy of M14 landmine (about 29g TNT explosive energy was simulated, to compare the ratio of explosive force equivalent to weight calculated between experimental animals and randomly selected adults. Results No significant change in blood pressure was observed at different time points before and after injuries. A broom-like change was found in the injured limb by the general observation. The subareas and pathological changes of injured limb coincided with the typical limb injuries produced by landmine explosion. Damage in different degrees was found in distant organs, and the wound characteristics and injury of major organs were in accordance with the reports of relevant literature. The ratio of explosive equivalent to weight of experimental animals (0.50±0.04g TNT/kg was similar to that of randomly selected adults (0.51±0.05g TNT/kg. Conclusion The present animal model could simulate the landmine explosive injuries, and may be used in research of landmine explosive injuries. DOI: 10.11855/j.issn.0577-7402.2014.01.14

  14. An animal model of spontaneous metabolic syndrome: Nile grass rat.

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    Noda, Kousuke; Melhorn, Mark I; Zandi, Souska; Frimmel, Sonja; Tayyari, Faryan; Hisatomi, Toshio; Almulki, Lama; Pronczuk, Andrzej; Hayes, K C; Hafezi-Moghadam, Ali

    2010-07-01

    Metabolic syndrome (MetS) is a prevalent and complex disease, characterized by the variable coexistence of obesity, dyslipidemia, hyperinsulinaemia, and hypertension. The alarming rise in the prevalence of metabolic disorders makes it imperative to innovate preventive or therapeutic measures for MetS and its complications. However, the elucidation of the pathogenesis of MetS has been hampered by the lack of realistic models. For example, the existing animal models of MetS, i.e., genetically engineered rodents, imitate certain aspects of the disease, while lacking other important components. Defining the natural course of MetS in a spontaneous animal model of the disease would be desirable. Here, we introduce the Nile grass rat (NGR), Arvicanthis niloticus, as a novel model of MetS. Studies of over 1100 NGRs in captivity, fed normal chow, revealed that most of these animals spontaneously develop dyslipidemia (P<0.01), and hyperglycemia (P<0.01) by 1 yr of age. Further characterization showed that the diabetic rats develop liver steatosis, abdominal fat accumulation, nephropathy, atrophy of pancreatic islets of Langerhans, fatty streaks in the aorta, and hypertension (P<0.01). Diabetic NGRs in the early phase of the disease develop hyperinsulinemia, and show a strong inverse correlation between plasma adiponectin and HbA1c levels (P<0.01). These data indicate that the NGR is a valuable, spontaneous model for exploring the etiology and pathophysiology of MetS as well as its various complications.

  15. Animal Modelling of Interstitial Cystitis/Bladder Pain Syndrome.

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    Birder, Lori; Andersson, Karl-Erik

    2018-01-01

    The etiology of interstitial cystitis/bladder pain syndrome (IC/BPS) remains elusive and may involve multiple causes. To better understand its pathophysiology, many efforts have been made to create IC/BPS models. Most existing models of IC/BPS strive to recreate bladder-related features by applying noxious intravesical or systemic stimuli to healthy animals. These models are useful to help understand various mechanisms; however, they are limited to demonstrating how the bladder and nervous system respond to noxious stimuli, and are not representative of the complex interactions and pathophysiology of IC/BPS. To study the various factors that may be relevant for IC/BPS, at least 3 different types of animal models are commonly used: (1) bladder-centric models, (2) models with complex mechanisms, and (3) psychological and physical stressors/natural disease models. It is obvious that all aspects of the human disease cannot be mimicked by a single model. It may be the case that several models, each contributing to a piece of the puzzle, are required to recreate a reasonable picture of the pathophysiology and time course of the disease(s) diagnosed as IC/BPS, and thus to identify reasonable targets for treatment.

  16. Tumor glucose metabolism imaged in vivo in small animals with whole-body photoacoustic computed tomography

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    Chatni, Muhammad Rameez; Xia, Jun; Sohn, Rebecca; Maslov, Konstantin; Guo, Zijian; Zhang, Yu; Wang, Kun; Xia, Younan; Anastasio, Mark; Arbeit, Jeffrey; Wang, Lihong V.

    2012-07-01

    With the increasing use of small animals for human disease studies, small-animal whole-body molecular imaging plays an important role in biomedical research. Currently, none of the existing imaging modalities can provide both anatomical and glucose molecular information, leading to higher costs of building dual-modality systems. Even with image co-registration, the spatial resolution of the molecular imaging modality is not improved. Utilizing a ring-shaped confocal photoacoustic computed tomography system, we demonstrate, for the first time, that both anatomy and glucose uptake can be imaged in a single modality. Anatomy was imaged with the endogenous hemoglobin contrast, and glucose metabolism was imaged with a near-infrared dye-labeled 2-deoxyglucose.

  17. Sleep and Obesity: A focus on animal models

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    Mavanji, Vijayakumar; Billington, Charles J.; Kotz, Catherine M.; Teske, Jennifer A.

    2012-01-01

    The rapid rise in obesity prevalence in the modern world parallels a significant reduction in restorative sleep (Agras et al., 2004; Dixon et al., 2007; Dixon et al., 2001; Gangwisch and Heymsfield, 2004; Gupta et al., 2002; Sekine et al., 2002; Vioque et al., 2000; Wolk et al., 2003). Reduced sleep time and quality increases the risk for obesity, but the underlying mechanisms remain unclear (Gangwisch et al., 2005; Hicks et al., 1986; Imaki et al., 2002; Jennings et al., 2007; Moreno et al., 2006). A majority of the theories linking human sleep disturbances and obesity rely on self-reported sleep. However, studies with objective measurements of sleep/wake parameters suggest a U-shaped relationship between sleep and obesity. Studies in animal models are needed to improve our understanding of the association between sleep disturbances and obesity. Genetic and experimenter-induced models mimicking characteristics of human obesity are now available and these animal models will be useful in understanding whether sleep disturbances determine propensity for obesity, or result from obesity. These models exhibit weight gain profiles consistently different from control animals. Thus a careful evaluation of animal models will provide insight into the relationship between sleep disturbances and obesity in humans. In this review we first briefly consider the fundamentals of sleep and key sleep disturbances, such as sleep fragmentation and excessive daytime sleepiness (EDS), observed in obese individuals. Then we consider sleep deprivation studies and the role of circadian alterations in obesity. We describe sleep/wake changes in various rodent models of obesity and obesity resistance. Finally, we discuss possible mechanisms linking sleep disturbances with obesity. PMID:22266350

  18. Sex Differences in Animal Models: Focus on Addiction

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    Becker, Jill B.

    2016-01-01

    The purpose of this review is to discuss ways to think about and study sex differences in preclinical animal models. We use the framework of addiction, in which animal models have excellent face and construct validity, to illustrate the importance of considering sex differences. There are four types of sex differences: qualitative, quantitative, population, and mechanistic. A better understanding of the ways males and females can differ will help scientists design experiments to characterize better the presence or absence of sex differences in new phenomena that they are investigating. We have outlined major quantitative, population, and mechanistic sex differences in the addiction domain using a heuristic framework of the three established stages of the addiction cycle: binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation. Female rats, in general, acquire the self-administration of drugs and alcohol more rapidly, escalate their drug taking with extended access more rapidly, show more motivational withdrawal, and (where tested in animal models of “craving”) show greater reinstatement. The one exception is that female rats show less motivational withdrawal to alcohol. The bases for these quantitative sex differences appear to be both organizational, in that estradiol-treated neonatal animals show the male phenotype, and activational, in that the female phenotype depends on the effects of gonadal hormones. In animals, differences within the estrous cycle can be observed but are relatively minor. Such hormonal effects seem to be most prevalent during the acquisition of drug taking and less influential once compulsive drug taking is established and are linked largely to progesterone and estradiol. This review emphasizes not only significant differences in the phenotypes of females and males in the domain of addiction but emphasizes the paucity of data to date in our understanding of those differences. PMID:26772794

  19. Tumor microenvironment in focus: LA-ICP-MS bioimaging of a preclinical tumor model upon treatment with platinum(IV)-based anticancer agents.

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    Theiner, Sarah; Kornauth, Christoph; Varbanov, Hristo P; Galanski, Markus; Van Schoonhoven, Sushilla; Heffeter, Petra; Berger, Walter; Egger, Alexander E; Keppler, Bernhard K

    2015-08-01

    The selection of drug candidates for entering clinical development relies on in vivo testing in (solid) tumor animal models. However, the heterogeneity of tumor tissue (e.g. in terms of drug uptake or tissue composition) is rarely considered when testing novel drug candidates. Therefore, we used the murine colon cancer CT-26 tumor model to study the spatially-resolved drug distribution in tumor tissue upon repetitive treatment of animals over two weeks with three investigational platinum(IV)-based anticancer agents, oxaliplatin or satraplatin. A quantitative laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) imaging method revealed a heterogeneous platinum distribution, which correlated well with the histologic features of the tumor and surrounding tissue at the microscopic level. In most of the cases, higher amounts of intratumoral platinum were found in the surrounding tissue than in the malignant parts of the sample. This indicates that determination of average platinum amounts (e.g. by microwave-assisted digestion of the sample followed by analysis with ICP-MS) might overestimate the drug uptake in tumor tissue causing misleading conclusions. In addition, we studied the platinum distribution in the kidneys of treated animals to probe if accumulation in the cortex and medulla predict potential nephrotoxicity. A 10-fold increase of platinum in the cortex of the kidney over the medulla was observed for oxaliplatin and satraplatin. Although these findings are similar to those in the platinum distribution of the nephrotoxic anticancer drug cisplatin, treatment with the compounds of our study did not show signs of nephrotoxicity in clinical use or clinical trials (oxaliplatin, satraplatin) and did not result in the alteration of renal structures. Thus, predicting the side effects based on bioimaging data by LA-ICP-MS should be considered with caution. To the best of our knowledge, this is the first LA-ICP-MS study on spatially-resolved platinum

  20. Neural models on temperature regulation for cold-stressed animals

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    Horowitz, J. M.

    1975-01-01

    The present review evaluates several assumptions common to a variety of current models for thermoregulation in cold-stressed animals. Three areas covered by the models are discussed: signals to and from the central nervous system (CNS), portions of the CNS involved, and the arrangement of neurons within networks. Assumptions in each of these categories are considered. The evaluation of the models is based on the experimental foundations of the assumptions. Regions of the nervous system concerned here include the hypothalamus, the skin, the spinal cord, the hippocampus, and the septal area of the brain.

  1. Modelo de tumor de pulmão em rato com o carcinossarcoma de Walker Lung tumor model in rats with Walker’s carcinosarcoma

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    Antero Gomes Neto

    2002-02-01

    Full Text Available OBJETIVO: Desenvolver um modelo de tumor pulmonar em ratos com o carcinossarcoma de Walker e verificar in vivo a presença de tumor por meio de tomografia computadorizada (TC. MÉTODOS: Ratos Wistar fêmeas (n=47 foram anestesiados com pentobarbital, intubados por traqueostomia e submetidos a toracotomia para injeção no parênquima pulmonar de células do tumor de Walker ou do veículo das mesmas. O estudo consistiu de duas etapas: na primeira desenvolveu-se a técnica de implante do tumor e estabeleceu-se o número de células necessário para um bom índice de pega tumoral. Na segunda etapa, determinou-se o volume do tumor em cm³ (Dxd²/2 através de TC e necropsia (6° dia do implante, e analizou-se a sobrevida dos animais. RESULTADOS: O índice de pega do tumor foi 93,3%, sendo 81,8% na primeira etapa e 100% na segunda. A mortalidade cirúrgica foi 17,0%. As medidas dos tumores foram semelhantes (0,099 vs. 0,111 cm³ na tomografia e na necropsia, respectivamente (r=0,993; pOBJECTIVE: To develop a lung tumor model in rats using Walker’s carcinosarcoma and to verify the presence in vivo of tumors using computerized tomography (CT. METHODS: Female Wistar rats (n=47 were anesthetized with pentobarbital, intubated through tracheostomy and submitted to thoracotomy; subsequently a 50-70 mu L volume containing Walker’s tumor cells, or the suspension of these same cells, was injected into the lung parenchyma. The study consisted of two phases: in the first a tumor implantation technique was developed and the number of cells required to attain a satisfactory tumor development rate was established. In the second phase, the tumor volume in cm³ (Dxd²/2 was determined through CT scan and necropsis, and the survival rates were analyzed. RESULTS: The overall tumor development rate was 93.3%, or rather, 81.1% in the first phase and 100% in the second. The surgical mortality rate was 17.0%. The average tumor volume was similar (0.099 vs. 0.111 cm

  2. Large Animal Models for Foamy Virus Vector Gene Therapy

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    Peter A. Horn

    2012-12-01

    Full Text Available Foamy virus (FV vectors have shown great promise for hematopoietic stem cell (HSC gene therapy. Their ability to efficiently deliver transgenes to multi-lineage long-term repopulating cells in large animal models suggests they will be effective for several human hematopoietic diseases. Here, we review FV vector studies in large animal models, including the use of FV vectors with the mutant O6-methylguanine-DNA methyltransferase, MGMTP140K to increase the number of genetically modified cells after transplantation. In these studies, FV vectors have mediated efficient gene transfer to polyclonal repopulating cells using short ex vivo transduction protocols designed to minimize the negative effects of ex vivo culture on stem cell engraftment. In this regard, FV vectors appear superior to gammaretroviral vectors, which require longer ex vivo culture to effect efficient transduction. FV vectors have also compared favorably with lentiviral vectors when directly compared in the dog model. FV vectors have corrected leukocyte adhesion deficiency and pyruvate kinase deficiency in the dog large animal model. FV vectors also appear safer than gammaretroviral vectors based on a reduced frequency of integrants near promoters and also near proto-oncogenes in canine repopulating cells. Together, these studies suggest that FV vectors should be highly effective for several human hematopoietic diseases, including those that will require relatively high percentages of gene-modified cells to achieve clinical benefit.

  3. Behavioral impairments in animal models for zinc deficiency

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    Simone eHagmeyer

    2015-01-01

    Full Text Available Apart from teratogenic and pathological effects of zinc deficiency such as the occurrence of skin lesions, anorexia, growth retardation, depressed wound healing, altered immune function, impaired night vision, and alterations in taste and smell acuity, characteristic behavioral changes in animal models and human patients suffering from zinc deficiency have been observed. Given that it is estimated that about 17% of the worldwide population are at risk for zinc deficiency and that zinc deficiency is associated with a variety of brain disorders and disease states in humans, it is of major interest to investigate, how these behavioral changes will affect the individual and a putative course of a disease. Thus, here, we provide a state of the art overview about the behavioral phenotypes observed in various models of zinc deficiency, among them environmentally produced zinc deficient animals as well as animal models based on a genetic alteration of a particular zinc homeostasis gene. Finally, we compare the behavioral phenotypes to the human condition of mild to severe zinc deficiency and provide a model, how zinc deficiency that is associated with many neurodegenerative and neuropsychological disorders might modify the disease pathologies.

  4. Calcium-activated potassium channels mediated blood-brain tumor barrier opening in a rat metastatic brain tumor model

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    Ong John M

    2007-03-01

    Full Text Available Abstract Background The blood-brain tumor barrier (BTB impedes the delivery of therapeutic agents to brain tumors. While adequate delivery of drugs occurs in systemic tumors, the BTB limits delivery of anti-tumor agents into brain metastases. Results In this study, we examined the function and regulation of calcium-activated potassium (KCa channels in a rat metastatic brain tumor model. We showed that intravenous infusion of NS1619, a KCa channel agonist, and bradykinin selectively enhanced BTB permeability in brain tumors, but not in normal brain. Iberiotoxin, a KCa channel antagonist, significantly attenuated NS1619-induced BTB permeability increase. We found KCa channels and bradykinin type 2 receptors (B2R expressed in cultured human metastatic brain tumor cells (CRL-5904, non-small cell lung cancer, metastasized to brain, human brain microvessel endothelial cells (HBMEC and human lung cancer brain metastasis tissues. Potentiometric assays demonstrated the activity of KCa channels in metastatic brain tumor cells and HBMEC. Furthermore, we detected higher expression of KCa channels in the metastatic brain tumor tissue and tumor capillary endothelia as compared to normal brain tissue. Co-culture of metastatic brain tumor cells and brain microvessel endothelial cells showed an upregulation of KCa channels, which may contribute to the overexpression of KCa channels in tumor microvessels and selectivity of BTB opening. Conclusion These findings suggest that KCa channels in metastatic brain tumors may serve as an effective target for biochemical modulation of BTB permeability to enhance selective delivery of chemotherapeutic drugs to metastatic brain tumors.

  5. High dose lansoprazole combined with metronomic chemotherapy: a phase I/II study in companion animals with spontaneously occurring tumors.

    Science.gov (United States)

    Spugnini, Enrico P; Buglioni, Sabrina; Carocci, Francesca; Francesco, Menicagli; Vincenzi, Bruno; Fanciulli, Maurizio; Fais, Stefano

    2014-08-21

    The treatment of human cancer has been seriously hampered for decades by resistance to chemotherapeutic drugs. A very efficient mechanism of tumor resistance to drugs is the proton pumps-mediated acidification of tumor microenvironment. Metronomic chemotherapy has shown efficacy in adjuvant fashion as well as in the treatment of pets with advanced disease. Moreover, we have shown in veterinary clinical settings that pre-treatment with proton-pumps inhibitors (PPI) increases tumor responsiveness to chemotherapeutics. In this study pet with spontaneously occurring cancer have been recruited to be treated by a combination of metronomic chemotherapy and high dose PPIs and their responses have been matched to those of a historical control of ten patients treated with metronomic chemotherapy alone. Single arm, non randomized phase II open study, with historical control group, evaluating safety and efficacy of the combination of metronomic chemotherapy and alkalization. Twenty-four companion animals (22 dogs and 2 cats) were treated adding to their metronomic chemotherapy protocol the pump inhibitor lansoprazole at high dose, and a water alkalizer. Their responses have been evaluated by clinical and instrumental evaluation and matched to those of the control group. The protocol was overall well tolerated, with only two dogs experiencing side effects due to gastric hypochlorhydria consisting with vomiting and or diarrhea. In terms of overall response, in the alkalized cohort, 18 out of 24 had partial or complete responses (75%), two patients had a stable disease and the remaining patients experienced no response or progressive disease. On the other hand, only one patient in the control group experienced a complete response (10%) and three other experienced short lived responses. Median time to terminal event was 34 weeks for the experimental group versus 2 weeks in the controls (p= 0.042). Patient alkalization has shown to be well tolerated and to increase tumor response

  6. Peptide Mediated In Vivo Tumor Targeting of Nanoparticles through Optimization in Single and Multilayer In Vitro Cell Models

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    Celina Yang

    2018-03-01

    Full Text Available Optimizing the interface between nanoparticles (NPs and the biological environment at various levels should be considered for improving delivery of NPs to the target tumor area. For NPs to be successfully delivered to cancer cells, NPs needs to be functionalized for circulation through the blood vessels. In this study, accumulation of Polyethylene Glycol (PEG functionalized gold nanoparticles (GNPs was first tested using in vitro monolayer cells and multilayer cell models prior to in vivo models. A diameter of 10 nm sized GNP was selected for this study for sufficient penetration through tumor tissue. The surfaces of the GNPs were modified with PEG molecules, to improve circulation time by reducing non-specific uptake by the reticuloendothelial system (RES in animal models, and with a peptide containing integrin binding domain, RGD (arginyl-glycyl-aspartic acid, to improve internalization at the cellular level. A 10–12% accumulation of the injected GNP dose within the tumor was observed in vivo and the GNPs remained within the tumor tissue up to 72 h. This study suggests an in vitro platform for optimizing the accumulation of NP complexes in cells and tissue structures before testing them in animal models. Higher accumulation within the tumor in vivo upon surface modification is a promising outcome for future applications where GNPs can be used for drug delivery and radiation therapy.

  7. Relevance of animal models to human tardive dyskinesia

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    Blanchet Pierre J

    2012-03-01

    Full Text Available Abstract Tardive dyskinesia remains an elusive and significant clinical entity that can possibly be understood via experimentation with animal models. We conducted a literature review on tardive dyskinesia modeling. Subchronic antipsychotic drug exposure is a standard approach to model tardive dyskinesia in rodents. Vacuous chewing movements constitute the most common pattern of expression of purposeless oral movements and represent an impermanent response, with individual and strain susceptibility differences. Transgenic mice are also used to address the contribution of adaptive and maladaptive signals induced during antipsychotic drug exposure. An emphasis on non-human primate modeling is proposed, and past experimental observations reviewed in various monkey species. Rodent and primate models are complementary, but the non-human primate model appears more convincingly similar to the human condition and better suited to address therapeutic issues against tardive dyskinesia.

  8. Modelling gait transition in two-legged animals

    Science.gov (United States)

    Pinto, Carla M. A.; Santos, Alexandra P.

    2011-12-01

    The study of locomotor patterns has been a major research goal in the last decades. Understanding how intralimb and interlimb coordination works out so well in animals' locomotion is a hard and challenging task. Many models have been proposed to model animal's rhythms. These models have also been applied to the control of rhythmic movements of adaptive legged robots, namely biped, quadruped and other designs. In this paper we study gait transition in a central pattern generator (CPG) model for bipeds, the 4-cells model. This model is proposed by Golubitsky, Stewart, Buono and Collins and is studied further by Pinto and Golubitsky. We briefly resume the work done by Pinto and Golubitsky. We compute numerically gait transition in the 4-cells CPG model for bipeds. We use Morris-Lecar equations and Wilson-Cowan equations as the internal dynamics for each cell. We also consider two types of coupling between the cells: diffusive and synaptic. We obtain secondary gaits by bifurcation of primary gaits, by varying the coupling strengths. Nevertheless, some bifurcating branches could not be obtained, emphasizing the fact that despite analytically those bifurcations exist, finding them is a hard task and requires variation of other parameters of the equations. We note that the type of coupling did not influence the results.

  9. Animal models of social anxiety disorder and their validity criteria.

    Science.gov (United States)

    Réus, Gislaine Z; Dos Santos, Maria Augusta B; Abelaira, Helena M; Quevedo, João

    2014-09-26

    Anxiety disorders pose one of the largest threats to global mental health, and they predominantly emerge early in life. Social anxiety disorder, also known as social phobia, is the most common of all anxiety disorders. Moreover, it has severe consequences and is a disabling disorder that can cause an individual to be unable to perform the tasks of daily life. Social anxiety disorder is associated with the subsequent development of major depression and other mental diseases, as well as increased substance abuse. Although some neurobiological alterations have been found to be associated with social anxiety disorder, little is known about this disorder. Animal models are useful tools for the investigation of this disorder, as well as for finding new pharmacological targets for treatment. Thus, this review will highlight the main animal models of anxiety associated with social phobia. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Gender Differences in Animal Models of Posttraumatic Stress Disorder

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    Hagit Cohen

    2011-01-01

    Full Text Available Epidemiological studies report higher prevalence rates of stress-related disorders such as acute stress disorder and post-traumatic stress disorder (PTSD in women than in men following exposure to trauma. It is still not clear whether this greater prevalence in woman reflects a greater vulnerability to stress-related psychopathology. A number of individual and trauma-related characteristics have been hypothesized to contribute to these gender differences in physiological and psychological responses to trauma, differences in appraisal, interpretation or experience of threat, coping style or social support. In this context, the use of an animal model for PTSD to analyze some of these gender-related differences may be of particular utility. Animal models of PTSD offer the opportunity to distinguish between biological and socio-cultural factors, which so often enter the discussion about gender differences in PTSD prevalence.

  11. Altered glial plasticity in animal models for mood disorders.

    Science.gov (United States)

    Czéh, Boldizsár; Fuchs, Eberhard; Flügge, Gabriele

    2013-10-01

    Numerous clinical evidences support the notion that glial changes in fronto-limbic brain areas could contribute to the pathophysiology of mood disorders. Glial alterations have been reported not only in patients, but also in various kinds of animal models for depression. Molecular and cellular data suggest that all the major classes of glial cells are affected in these conditions, including astrocytes, oligodendrocytes, NG2-positive cells and microglia. The aim of this review was to summarize the currently available experimental results demonstrating alterations in glial morphology and functioning in animal models for mood disorders. Better understanding of these glial changes affecting neuronal activity could help us to identify novel targets for the development of antidepressant drugs.

  12. Cardiovascular Changes in Animal Models of Metabolic Syndrome

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    Alexandre M. Lehnen

    2013-01-01

    Full Text Available Metabolic syndrome has been defined as a group of risk factors that directly contribute to the development of cardiovascular disease and/or type 2 diabetes. Insulin resistance seems to have a fundamental role in the genesis of this syndrome. Over the past years to the present day, basic and translational research has used small animal models to explore the pathophysiology of metabolic syndrome and to develop novel therapies that might slow the progression of this prevalent condition. In this paper we discuss the animal models used for the study of metabolic syndrome, with particular focus on cardiovascular changes, since they are the main cause of death associated with the condition in humans.

  13. Animal models of tic disorders: a translational perspective.

    Science.gov (United States)

    Godar, Sean C; Mosher, Laura J; Di Giovanni, Giuseppe; Bortolato, Marco

    2014-12-30

    Tics are repetitive, sudden movements and/or vocalizations, typically enacted as maladaptive responses to intrusive premonitory urges. The most severe tic disorder, Tourette syndrome (TS), is a childhood-onset condition featuring multiple motor and at least one phonic tic for a duration longer than 1 year. The pharmacological treatment of TS is mainly based on antipsychotic agents; while these drugs are often effective in reducing tic severity and frequency, their therapeutic compliance is limited by serious motor and cognitive side effects. The identification of novel therapeutic targets and development of better treatments for tic disorders is conditional on the development of animal models with high translational validity. In addition, these experimental tools can prove extremely useful to test hypotheses on the etiology and neurobiological bases of TS and related conditions. In recent years, the translational value of these animal models has been enhanced, thanks to a significant re-organization of our conceptual framework of neuropsychiatric disorders, with a greater focus on endophenotypes and quantitative indices, rather than qualitative descriptors. Given the complex and multifactorial nature of TS and other tic disorders, the selection of animal models that can appropriately capture specific symptomatic aspects of these conditions can pose significant theoretical and methodological challenges. In this article, we will review the state of the art on the available animal models of tic disorders, based on genetic mutations, environmental interventions as well as pharmacological manipulations. Furthermore, we will outline emerging lines of translational research showing how some of these experimental preparations have led to significant progress in the identification of novel therapeutic targets for tic disorders. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. A novel animal model of dysphagia following stroke.

    Science.gov (United States)

    Sugiyama, Naoto; Nishiyama, Eiji; Nishikawa, Yukitoshi; Sasamura, Takashi; Nakade, Shinji; Okawa, Katsumasa; Nagasawa, Tadashi; Yuki, Akane

    2014-02-01

    Patients who have an ischemic stroke are at high risk of swallowing disorders. Aspiration due to swallowing disorders, specifically delayed trigger of the pharyngeal stage of swallowing, predisposes such patients to pneumonia. In the present study, we evaluated swallowing reflex in a rat model of transient middle cerebral artery occlusion (tMCAO), which is one of the most common experimental animal models of cerebral ischemia, in order to develop a novel animal model of dysphagia following ischemic stroke. A swallowing reflex was elicited by a 10-s infusion of distilled water (DW) to the pharyngolaryngeal region in the tMCAO rat model. Swallowing reflex was estimated using the electromyographic activity of the mylohyoid muscle from 1 to 3 weeks after surgery. Two weeks after tMCAO, the number of swallows significantly decreased and the onset latency of the first swallow was prolonged compared with that of the sham group. The number of swallows in rats significantly increased by infusions of 10 mM citric acid and 0.6 μM capsaicin to the pharyngolaryngeal region compared with the number from infusion of DW. It has been reported that sensory stimulation of the pharyngolaryngeal region with citric acid, capsaicin, and L-menthol ameliorates hypofunction of pharyngeal-stage swallowing in dysphagia patients. Therefore, the tMCAO rat model may show some of the symptoms of pharyngeal-stage swallowing disorders, similar to those in patients with ischemic stroke. This rat tMCAO model has the potential to become a novel animal model of dysphagia following stroke that is useful for development of therapeutic methods and drugs.

  15. NAFLD, Estrogens, and Physical Exercise: The Animal Model

    Directory of Open Access Journals (Sweden)

    Jean-Marc Lavoie

    2012-01-01

    Full Text Available One segment of the population that is particularly inclined to liver fat accumulation is postmenopausal women. Although nonalcoholic hepatic steatosis is more common in men than in women, after menopause there is a reversal in gender distribution. At the present time, weight loss and exercise are regarded as first line treatments for NAFLD in postmenopausal women, as it is the case for the management of metabolic syndrome. In recent years, there has been substantial evidence coming mostly from the use of the animal model, that indeed estrogens withdrawal is associated with modifications of molecular markers favouring the activity of metabolic pathways ultimately leading to liver fat accumulation. In addition, the use of the animal model has provided physiological and molecular evidence that exercise training provides estrogens-like protective effects on liver fat accumulation and its consequences. The purpose of the present paper is to present information relative to the development of a state of NAFLD resulting from the absence of estrogens and the role of exercise training, emphasizing on the contribution of the animal model on these issues.

  16. Stem cells in animal asthma models: a systematic review.

    Science.gov (United States)

    Srour, Nadim; Thébaud, Bernard

    2014-12-01

    Asthma control frequently falls short of the goals set in international guidelines. Treatment options for patients with poorly controlled asthma despite inhaled corticosteroids and long-acting β-agonists are limited, and new therapeutic options are needed. Stem cell therapy is promising for a variety of disorders but there has been no human clinical trial of stem cell therapy for asthma. We aimed to systematically review the literature regarding the potential benefits of stem cell therapy in animal models of asthma to determine whether a human trial is warranted. The MEDLINE and Embase databases were searched for original studies of stem cell therapy in animal asthma models. Nineteen studies were selected. They were found to be heterogeneous in their design. Mesenchymal stromal cells were used before sensitization with an allergen, before challenge with the allergen and after challenge, most frequently with ovalbumin, and mainly in BALB/c mice. Stem cell therapy resulted in a reduction of bronchoalveolar lavage fluid inflammation and eosinophilia as well as Th2 cytokines such as interleukin-4 and interleukin-5. Improvement in histopathology such as peribronchial and perivascular inflammation, epithelial thickness, goblet cell hyperplasia and smooth muscle layer thickening was universal. Several studies showed a reduction in airway hyper-responsiveness. Stem cell therapy decreases eosinophilic and Th2 inflammation and is effective in several phases of the allergic response in animal asthma models. Further study is warranted, up to human clinical trials. Copyright © 2014 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  17. Modeling DNA structure and processes through animation and kinesthetic visualizations

    Science.gov (United States)

    Hager, Christine

    There have been many studies regarding the effectiveness of visual aids that go beyond that of static illustrations. Many of these have been concentrated on the effectiveness of visual aids such as animations and models or even non-traditional visual aid activities like role-playing activities. This study focuses on the effectiveness of three different types of visual aids: models, animation, and a role-playing activity. Students used a modeling kit made of Styrofoam balls and toothpicks to construct nucleotides and then bond nucleotides together to form DNA. Next, students created their own animation to depict the processes of DNA replication, transcription, and translation. Finally, students worked in teams to build proteins while acting out the process of translation. Students were given a pre- and post-test that measured their knowledge and comprehension of the four topics mentioned above. Results show that there was a significant gain in the post-test scores when compared to the pre-test scores. This indicates that the incorporated visual aids were effective methods for teaching DNA structure and processes.

  18. Vestibular animal models: contributions to understanding physiology and disease.

    Science.gov (United States)

    Straka, Hans; Zwergal, Andreas; Cullen, Kathleen E

    2016-04-01

    Our knowledge of the vestibular sensory system, its functional significance for gaze and posture stabilization, and its capability to ensure accurate spatial orientation perception and spatial navigation has greatly benefitted from experimental approaches using a variety of vertebrate species. This review summarizes the attempts to establish the roles of semicircular canal and otolith endorgans in these functions followed by an overview of the most relevant fields of vestibular research including major findings that have advanced our understanding of how this system exerts its influence on reflexive and cognitive challenges encountered during daily life. In particular, we highlight the contributions of different animal models and the advantage of using a comparative research approach. Cross-species comparisons have established that the morpho-physiological properties underlying vestibular signal processing are evolutionarily inherent, thereby disclosing general principles. Based on the documented success of this approach, we suggest that future research employing a balanced spectrum of standard animal models such as fish/frog, mouse and primate will optimize our progress in understanding vestibular processing in health and disease. Moreover, we propose that this should be further supplemented by research employing more "exotic" species that offer unique experimental access and/or have specific vestibular adaptations due to unusual locomotor capabilities or lifestyles. Taken together this strategy will expedite our understanding of the basic principles underlying vestibular computations to reveal relevant translational aspects. Accordingly, studies employing animal models are indispensible and even mandatory for the development of new treatments, medication and technical aids (implants) for patients with vestibular pathologies.

  19. The establishment of animal model of acute massive pulmonary embolism

    International Nuclear Information System (INIS)

    Lu Junliang; Yang Ning; Yang Jianping; Ma Junshan; Zhao Shijun

    2008-01-01

    Objective: To find a way of establishing the model of acute massive pulmonary embolism in dog. Methods: Seven dogs were selected with self-clots made outside the body transferring through a 10 F guiding catheter into the central branch of pulmonary artery via the femoral vein approach on one side and then under pressure monitor of pulmonary artery until the very branch of pulmonary artery was occluded. Blood gas and pulmonary arterial pressure were tested before and after the embolization, Pulmonary artery pressure was continuously monitored together with the examinations of angiography. The bilateral lung specimens were resected for histological examination 12 hours in average after the embolization for comparative study. Results: One animal died of cardiogenic shock after clots injection; the other one presented with tachycardia and premature ventricular beat causing partial recanalization 12 h later. The others were occluded successfully in central branch of pulmonary artery and the pulmonary arterial pressure reached above 50 mmHg after occlusion. Pathologic examination showed the formation of red and mix thrombi within the vascular lumens. Conclusions: This method for making acute massive pulmonary embolism animal model was reliable, feasible and reproducible, and could provide an animal model of acute massive pulmonary embolism for other correlative experiments. (authors)

  20. Tumor hypoxia - A confounding or exploitable factor in interstitial brachytherapy? Effects of tissue trauma in an experimental rat tumor model

    NARCIS (Netherlands)

    van den Berg, AP; van Geel, CAJF; van Hooije, CMC; van der Kleij, AJ; Visser, AG

    2000-01-01

    Purpose: To evaluate the potential effects of tumor hypoxia induced by afterloading catheter implantation on the effectiveness of brachytherapy in a rat tumor model. Methods and Materials: Afterloading catheters (4) Here implanted in subcutaneously growing R1M rhabdomyosarcoma in female Wag/Rij

  1. Testing flow diversion in animal models: a systematic review.

    Science.gov (United States)

    Fahed, Robert; Raymond, Jean; Ducroux, Célina; Gentric, Jean-Christophe; Salazkin, Igor; Ziegler, Daniela; Gevry, Guylaine; Darsaut, Tim E

    2016-04-01

    Flow diversion (FD) is increasingly used to treat intracranial aneurysms. We sought to systematically review published studies to assess the quality of reporting and summarize the results of FD in various animal models. Databases were searched to retrieve all animal studies on FD from 2000 to 2015. Extracted data included species and aneurysm models, aneurysm and neck dimensions, type of flow diverter, occlusion rates, and complications. Articles were evaluated using a checklist derived from the Animal Research: Reporting of In Vivo Experiments (ARRIVE) guidelines. Forty-two articles reporting the results of FD in nine different aneurysm models were included. The rabbit elastase-induced aneurysm model was the most commonly used, with 3-month occlusion rates of 73.5%, (95%CI [61.9-82.6%]). FD of surgical sidewall aneurysms, constructed in rabbits or canines, resulted in high occlusion rates (100% [65.5-100%]). FD resulted in modest occlusion rates (15.4% [8.9-25.1%]) when tested in six complex canine aneurysm models designed to reproduce more difficult clinical contexts (large necks, bifurcation, or fusiform aneurysms). Adverse events, including branch occlusion, were rarely reported. There were no hemorrhagic complications. Articles complied with 20.8 ± 3.9 of 41 ARRIVE items; only a small number used randomization (3/42 articles [7.1%]) or a control group (13/42 articles [30.9%]). Preclinical studies on FD have shown various results. Occlusion of elastase-induced aneurysms was common after FD. The model is not challenging but standardized in many laboratories. Failures of FD can be reproduced in less standardized but more challenging surgical canine constructions. The quality of reporting could be improved.

  2. Imaging of Tumor-Associated Macrophages in a Transgenic Mouse Model of Orthotopic Ovarian Cancer.

    Science.gov (United States)

    He, Huanhuan; Chiu, Alan C; Kanada, Masamitsu; Schaar, Bruce T; Krishnan, Venkatesh; Contag, Christopher H; Dorigo, Oliver

    2017-10-01

    Tumor-associated macrophages (TAMs) are often associated with a poor prognosis in cancer. To gain a better understanding of cellular recruitment and dynamics of TAM biology during cancer progression, we established a novel transgenic mouse model for in vivo imaging of luciferase-expressing macrophages. B6.129P2-Lyz2 tm1(cre)Ifo /J mice, which express Cre recombinase under the control of the lysozyme M promoter (LysM) were crossed to Cre-lox Luc reporter mice (RLG), to produce LysM-LG mice whose macrophages express luciferase. Cell-type-specific luciferase expression in these mice was verified by flow cytometry, and via in vivo bioluminescence imaging under conditions where macrophages were either stimulated with lipopolysaccharide or depleted with clodronate liposomes. The distribution of activated macrophages was longitudinally imaged in two immunocompetent LysM-LG mouse models with either B16 melanoma or ID8 ovarian cancer cells. In vivo imaging of LysM-LG mice showed luciferase activity was generated by macrophages. Clodronate liposome-mediated depletion of macrophages lowered overall bioluminescence while lipopolysaccharide injection increased macrophage bioluminescence in both the B16 and ID8 models. Tracking macrophages weekly in tumor-bearing animals after intraperitoneal (i.p.) or intraovarian (i.o.) injection resulted in distinct, dynamic patterns of macrophage activity. Animals with metastatic ovarian cancer after i.p. injection exhibited significantly higher peritoneal macrophage activity compared to animals after i.o. injection. The LysM-LG model allows tracking of macrophage recruitment and activation during disease initiation and progression in a noninvasive manner. This model provides a tool to visualize and monitor the benefit of pharmacological interventions targeting macrophages in preclinical models.

  3. Doxorubicin-Loaded QuadraSphere Microspheres: Plasma Pharmacokinetics and Intratumoral Drug Concentration in an Animal Model of Liver Cancer

    International Nuclear Information System (INIS)

    Lee, Kwang-Hun; Liapi, Eleni A.; Cornell, Curt; Reb, Philippe; Buijs, Manon; Vossen, Josephina A.; Ventura, Veronica Prieto; Geschwind, Jean-Francois H.

    2010-01-01

    The purpose of this study was to evaluate, in vitro and in vivo, doxorubicin-loaded poly (vinyl alcohol-sodium acrylate) copolymer microspheres [QuadraSphere microspheres (QSMs)] for transcatheter arterial delivery in an animal model of liver cancer. Doxorubicin loading efficiency and release profile were first tested in vitro. In vivo, 15 rabbits, implanted with a Vx-2 tumor in the liver, were divided into three groups of five rabbits each, based on the time of euthanasia. Twenty-five milligrams of QSMs was diluted in 10 ml of a 10 mg/ml doxorubicin solution and 10 ml of nonionic contrast medium for a total volume of 20 ml. One milliliter of a drug-loaded QSM solution containing 5 mg of doxorubicin was injected into the tumor feeding artery. Plasma doxorubicin and doxorubicinol concentrations, and intratumoral and peritumoral doxorubicin tissue concentrations, were measured. Tumor specimens were pathologically evaluated to record tumor necrosis. As a control, one animal was blandly embolized with plain QSMs in each group. In vitro testing of QSM doxorubicin loadability and release over time showed 82-94% doxorubicin loadability within 2 h and 6% release within the first 6 h after loading, followed by a slow release pattern. In vivo, the doxorubicin plasma concentration declined at 40 min. The peak doxorubicin intratumoral concentration was observed at 3 days and remained detectable till the study's end point (7 days). Mean percentage tumor cell death in the doxorubicin QSM group was 90% at 7 days and 60% in the bland QSM embolization group. In conclusion, QSMs can be efficiently loaded with doxorubicin. Initial experiments with doxorubicin-loaded QSMs show a safe pharmacokinetic profile and effective tumor killing in an animal model of liver cancer.

  4. Acute liver failure: a critical appraisal of available animal models.

    Science.gov (United States)

    Bélanger, Mireille; Butterworth, Roger F

    2005-12-01

    The availability of adequate experimental models of acute liver failure (ALF) is of prime importance to provide a better understanding of this condition and allow the development and testing of new therapeutic approaches for patients with ALF. However, the numerous etiologies and complications of ALF contribute to the complexity of this condition and render the development of an ideal experimental model of ALF more difficult than expected. Instead, a number of different models that may be used for the study of specific aspects of ALF have been developed. The most common approaches used to induce ALFin experimental animals are surgical procedures, toxic liver injury,or a combination of both. Despite the high prevalence of viral hepatitis worldwide, very few satisfactory viral models of ALF are available. Established and newly developed models of ALF are reviewed.

  5. Evaluation of Tumor Angiogenesis with a Second-Generation US Contrast Medium in a Rat Breast Tumor Model

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Eun Young [Samsung Medical Center, Sungkyunkwan University School of Medicine (Korea, Republic of); Lee, Sang Hoon; Kim, Hak Hee; Kim, Sung Moon; Shin, Myung Jin; Kim, Nam Kug; Gong, Gyung Yub [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2008-06-15

    Tumor angiogenesis is an important factor for tumor growth, treatment response and prognosis. Noninvasive imaging methods for the evaluation of tumor angiogenesis have been studied, but a method for the quantification of tumor angiogenesis has not been established. This study was designed to evaluate tumor angiogenesis in a rat breast tumor model by the use of a contrast enhanced ultrasound (US) examination with a second-generation US contrast agent. The alkylating agent 19N-ethyl-N-nitrosourea (ENU) was injected into the intraperitoneal cavity of 30-day-old female Sprague-Dawley rats. Three to four months later, breast tumors were detected along the mammary lines of the rats. A total of 17 breast tumors larger than 1 cm in nine rats were evaluated by gray-scale US, color Doppler US and contrast-enhanced US using SonoVue. The results were recorded as digital video images; time-intensity curves and hemodynamic parameters were analyzed. Pathological breast tumor specimens were obtained just after the US examinations. The tumor specimens were stained with hematoxylin and eosin (H and E) and the expression of CD31, an endothelial cell marker, was determined by immunohistochemical staining. We also evaluated the pathological diagnosis of the tumors and the microvessel density (MVD). Spearman's correlation and the Kruskal-Wallis test were used for the analysis. The pathological diagnoses were 11 invasive ductal carcinomas and six benign intraductal epithelial proliferations. The MVD did not correlate with the pathological diagnosis. However, blood volume (BV) showed a statistically significant correlation with MVD (Spearman's correlation, p < 0.05). Contrast-enhanced US using a second-generation US contrast material was useful for the evaluation of tumor angiogenesis of breast tumors in the rat.

  6. Melittin restores proteasome function in an animal model of ALS

    Directory of Open Access Journals (Sweden)

    Lee Sang Min

    2011-06-01

    Full Text Available Abstract Amyotrophic lateral sclerosis (ALS is a paralyzing disorder characterized by the progressive degeneration and death of motor neurons and occurs both as a sporadic and familial disease. Mutant SOD1 (mtSOD1 in motor neurons induces vulnerability to the disease through protein misfolding, mitochondrial dysfunction, oxidative damage, cytoskeletal abnormalities, defective axonal transport- and growth factor signaling, excitotoxicity, and neuro-inflammation. Melittin is a 26 amino acid protein and is one of the components of bee venom which is used in traditional Chinese medicine to inhibit of cancer cell proliferation and is known to have anti-inflammatory and anti-arthritic effects. The purpose of the present study was to determine if melittin could suppress motor neuron loss and protein misfolding in the hSOD1G93A mouse, which is commonly used as a model for inherited ALS. Meltittin was injected at the 'ZuSanLi' (ST36 acupuncture point in the hSOD1G93A animal model. Melittin-treated animals showed a decrease in the number of microglia and in the expression level of phospho-p38 in the spinal cord and brainstem. Interestingly, melittin treatment in symptomatic ALS animals improved motor function and reduced the level of neuron death in the spinal cord when compared to the control group. Furthermore, we found increased of α-synuclein modifications, such as phosphorylation or nitration, in both the brainstem and spinal cord in hSOD1G93A mice. However, melittin treatment reduced α-synuclein misfolding and restored the proteasomal activity in the brainstem and spinal cord of symptomatic hSOD1G93A transgenic mice. Our research suggests a potential functional link between melittin and the inhibition of neuroinflammation in an ALS animal model.

  7. Evaluation of the toxicity of tirapazamine plus cisplatin in a mouse tumor model

    International Nuclear Information System (INIS)

    Adam, M.; Ottenjann, S.; Kuenzel, G.; Nieder, C.; Molls, M.; Busch, R.; Erhardt, W.

    2006-01-01

    Background and purpose: tirapazamine (TPZ) is an anticancer drug that is selectively activated by the low oxygen environment in solid tumors. Furthermore, TPZ also enhances the tumor cell-killing effect of cisplatin. So far, detailed information on the toxicity of combined treatment is rare. The authors evaluated the toxicity of TPZ in combination with cisplatin in a mouse tumor model. For this purpose, general toxicity was monitored and all inner organs were examined histologically. Material and methods: RIF-1 fibrosarcomas of murine origin growing in the right hindfoot dorsum of C3H mice were used. The animals were treated with 10 x 2 Gy irradiation plus six i.p. injections of 4 mg/kg cisplatin (total dose 24 mg/kg) together with varying doses of TPZ (0-28 mg/kg per injection; total dose 0, 43.2, 86.4, 129.6, 151.2, 172.8 mg/kg). Treatment was applied within 2 weeks (figure 1). Total observation period was up to 35 days. Results: combined treatment with TPZ led to a dose-dependent, significant decrease in motor activity (table 1) and body weight and an increase in mortality (figures 2 and 3, tables 2 and 3). Histological analyses showed areas of necrosis in the heart, liver and kidney and gastric ulcers (table 4). Cisplatin alone produced no severe toxicity. Tumor doubling times were TPZ dose-dependent and comparable with data from the literature (figures 4 and 5, table 3). (orig.)

  8. Current State of Animal (Mouse Modeling in Melanoma Research

    Directory of Open Access Journals (Sweden)

    Omer F. Kuzu

    2015-01-01

    Full Text Available Despite the considerable progress in understanding the biology of human cancer and technological advancement in drug discovery, treatment failure remains an inevitable outcome for most cancer patients with advanced diseases, including melanoma. Despite FDA-approved BRAF-targeted therapies for advanced stage melanoma showed a great deal of promise, development of rapid resistance limits the success. Hence, the overall success rate of melanoma therapy still remains to be one of the worst compared to other malignancies. Advancement of next-generation sequencing technology allowed better identification of alterations that trigger melanoma development. As development of successful therapies strongly depends on clinically relevant preclinical models, together with the new findings, more advanced melanoma models have been generated. In this article, besides traditional mouse models of melanoma, we will discuss recent ones, such as patient-derived tumor xenografts, topically inducible BRAF mouse model and RCAS/TVA-based model, and their advantages as well as limitations. Although mouse models of melanoma are often criticized as poor predictors of whether an experimental drug would be an effective treatment, development of new and more relevant models could circumvent this problem in the near future.

  9. Animal models of bone cancer pain: systematic review and meta-analyses.

    Science.gov (United States)

    Currie, Gillian L; Delaney, Ada; Bennett, Michael I; Dickenson, Anthony H; Egan, Kieren J; Vesterinen, Hanna M; Sena, Emily S; Macleod, Malcolm R; Colvin, Lesley A; Fallon, Marie T

    2013-06-01

    Pain can significantly decrease the quality of life of patients with advanced cancer. Current treatment strategies often provide inadequate analgesia and unacceptable side effects. Animal models of bone cancer pain are used in the development of novel pharmacological approaches. Here we conducted a systematic review and meta-analysis of publications describing in vivo modelling of bone cancer pain in which behavioural, general health, macroscopic, histological, biochemical, or electrophysiological outcomes were reported and compared to appropriate controls. In all, 150 publications met our inclusion criteria, describing 38 different models of bone cancer pain. Reported methodological quality was low; only 31% of publications reported blinded assessment of outcome, and 11% reported random allocation to group. No publication reported a sample size calculation. Studies that reported measures to reduce bias reported smaller differences in behavioural outcomes between tumour-bearing and control animals, and studies that presented a statement regarding a conflict of interest reported larger differences in behavioural outcomes. Larger differences in behavioural outcomes were reported in female animals, when cancer cells were injected into either the tibia or femur, and when MatLyLu prostate or Lewis Lung cancer cells were used. Mechanical-evoked pain behaviours were most commonly reported; however, the largest difference was observed in spontaneous pain behaviours. In the spinal cord astrocyte activation and increased levels of Substance P receptor internalisation, c-Fos, dynorphin, tumor necrosis factor-α and interleukin-1β have been reported in bone cancer pain models, suggesting several potential therapeutic targets. However, the translational impact of animal models on clinical pain research could be enhanced by improving methodological quality. Copyright © 2013. Published by Elsevier B.V.

  10. Animal models of gastrointestinal and liver diseases. Animal models of infant short bowel syndrome

    DEFF Research Database (Denmark)

    Sangild, Per Torp; Ney, Denise M; Sigalet, David L

    2014-01-01

    help but careful evaluation of the cellular mechanisms, safety and translational relevance of new procedures are required. Distal intestinal resection, without a functioning colon, results in the most severe complications and adaptation may depend on the age at resection (preterm, term, young, adult...... hormone, insulin-like growth factor 1, epidermal growth factor, keratinocyte growth factor). The greater size of rats, and especially young pigs, is an advantage for testing surgical procedures and nutritional interventions (e.g. PN, milk diets, long/short chain lipids, pre- and probiotics). Conversely......, newborn pigs and weanling rats represent a translational advantage for infant SBS due to their immature intestine. A balance among practical, economical, experimental and ethical constraints determines the choice of SBS model for each clinical or basic research question....

  11. Biochemical correlates in an animal model of depression

    International Nuclear Information System (INIS)

    Johnson, J.O.

    1986-01-01

    A valid animal model of depression was used to explore specific adrenergic receptor differences between rats exhibiting aberrant behavior and control groups. Preliminary experiments revealed a distinct upregulation of hippocampal beta-receptors (as compared to other brain regions) in those animals acquiring a response deficit as a result of exposure to inescapable footshock. Concurrent studies using standard receptor binding techniques showed no large changes in the density of alpha-adrenergic, serotonergic, or dopaminergic receptor densities. This led to the hypothesis that the hippocampal beta-receptor in responses deficient animals could be correlated with the behavioral changes seen after exposure to the aversive stimulus. Normalization of the behavior through the administration of antidepressants could be expected to reverse the biochemical changes if these are related to the mechanism of action of antidepressant drugs. This study makes three important points: (1) there is a relevant biochemical change in the hippocampus of response deficient rats which occurs in parallel to a well-defined behavior, (2) the biochemical and behavioral changes are normalized by antidepressant treatments exhibiting both serotonergic and adrenergic mechanisms of action, and (3) the mode of action of antidepressants in this model is probably a combination of serotonergic and adrenergic influences modulating the hippocampal beta-receptor. These results are discussed in relation to anatomical and biochemical aspects of antidepressant action

  12. Improved animal models for testing gene therapy for atherosclerosis.

    Science.gov (United States)

    Du, Liang; Zhang, Jingwan; De Meyer, Guido R Y; Flynn, Rowan; Dichek, David A

    2014-04-01

    Gene therapy delivered to the blood vessel wall could augment current therapies for atherosclerosis, including systemic drug therapy and stenting. However, identification of clinically useful vectors and effective therapeutic transgenes remains at the preclinical stage. Identification of effective vectors and transgenes would be accelerated by availability of animal models that allow practical and expeditious testing of vessel-wall-directed gene therapy. Such models would include humanlike lesions that develop rapidly in vessels that are amenable to efficient gene delivery. Moreover, because human atherosclerosis develops in normal vessels, gene therapy that prevents atherosclerosis is most logically tested in relatively normal arteries. Similarly, gene therapy that causes atherosclerosis regression requires gene delivery to an existing lesion. Here we report development of three new rabbit models for testing vessel-wall-directed gene therapy that either prevents or reverses atherosclerosis. Carotid artery intimal lesions in these new models develop within 2-7 months after initiation of a high-fat diet and are 20-80 times larger than lesions in a model we described previously. Individual models allow generation of lesions that are relatively rich in either macrophages or smooth muscle cells, permitting testing of gene therapy strategies targeted at either cell type. Two of the models include gene delivery to essentially normal arteries and will be useful for identifying strategies that prevent lesion development. The third model generates lesions rapidly in vector-naïve animals and can be used for testing gene therapy that promotes lesion regression. These models are optimized for testing helper-dependent adenovirus (HDAd)-mediated gene therapy; however, they could be easily adapted for testing of other vectors or of different types of molecular therapies, delivered directly to the blood vessel wall. Our data also supports the promise of HDAd to deliver long

  13. Doxorubicin-Loaded QuadraSphere Microspheres: Plasma Pharmacokinetics and Intratumoral Drug Concentration in an Animal Model of Liver Cancer

    OpenAIRE

    Lee, Kwang-Hun; Liapi, Eleni A.; Cornell, Curt; Reb, Philippe; Buijs, Manon; Vossen, Josephina A.; Ventura, Veronica Prieto; Geschwind, Jean-Francois H.

    2010-01-01

    The purpose of this study was to evaluate, in vitro and in vivo, doxorubicin-loaded poly (vinyl alcohol-sodium acrylate) copolymer microspheres [QuadraSphere microspheres (QSMs)] for transcatheter arterial delivery in an animal model of liver cancer. Doxorubicin loading efficiency and release profile were first tested in vitro. In vivo, 15 rabbits, implanted with a Vx-2 tumor in the liver, were divided into three groups of five rabbits each, based on the time of euthanasia. Twenty-five millig...

  14. Basic mechanisms of catastrophic epilepsy – overview from animal models

    Science.gov (United States)

    Galanopoulou, Aristea S.

    2013-01-01

    Infantile spasms are age-specific seizures of infantile epileptic encephalopathies that are usually associated with poor epilepsy and neurodevelopmental outcomes. The current treatments are not always effective and may be associated with significant side effects. Various mechanisms have been proposed as pathogenic for infantile spasms, including cortical or brainstem dysfunction, disruption of normal cortical-subcortical communications, genetic defects, inflammation, stress, developmental abnormalities. Many of these have been recently tested experimentally, resulting into the emergence of several animal models of infantile spasms. The stress theory of spasms yielded the corticotropin releasing hormone (CRH) induced model, which showed the higher proconvulsant potency of CRH in developing rats, although only limbic seizures were observed. Models of acute induction of infantile spasms in rodents include the N-methyl-D-aspartate (NMDA) model of emprosthotonic seizures, the prenatal betamethasone and prenatal stress variants of the NMDA model, and the γ-butyrolactone induced spasms in a Down’s syndrome mouse model. Chronic rodent models of infantile spasms include the tetrodotoxin model and the multiple-hit models in rats, as well as two genetic mouse models of interneuronopathies with infantile spasms due to loss of function of the aristaless X-linked homeobox related gene (ARX). This review discusses the emerging mechanisms for generation of infantile spasms and their associated chronic epileptic and dyscognitive phenotype as well as the recent progress in identifying pathways to better treat this epileptic encephalopathy. PMID:23312951

  15. Development of virtual hands using animation software and graphical modelling

    International Nuclear Information System (INIS)

    Oliveira, Erick da S.; Junior, Alberico B. de C.

    2016-01-01

    The numerical dosimetry uses virtual anthropomorphic simulators to represent the human being in computational framework and thus assess the risks associated with exposure to a radioactive source. With the development of computer animation software, the development of these simulators was facilitated using only knowledge of human anatomy to prepare various types of simulators (man, woman, child and baby) in various positions (sitting, standing, running) or part thereof (head, trunk and limbs). These simulators are constructed by loops of handling and due to the versatility of the method, one can create various geometries irradiation was not possible before. In this work, we have built an exhibition of a radiopharmaceutical scenario manipulating radioactive material using animation software and graphical modeling and anatomical database. (author)

  16. Animal models of gene-environment interactions in schizophrenia.

    Science.gov (United States)

    Ayhan, Yavuz; Sawa, Akira; Ross, Christopher A; Pletnikov, Mikhail V

    2009-12-07

    The pathogenesis of schizophrenia and related mental illnesses likely involves multiple interactions between susceptibility genes of small effects and environmental factors. Gene-environment interactions occur across different stages of neurodevelopment to produce heterogeneous clinical and pathological manifestations of the disease. The main obstacle for mechanistic studies of gene-environment interplay has been the paucity of appropriate experimental systems for elucidating the molecular pathways that mediate gene-environment interactions relevant to schizophrenia. Recent advances in psychiatric genetics and a plethora of experimental data from animal studies allow us to suggest a new approach to gene-environment interactions in schizophrenia. We propose that animal models based on identified genetic mutations and measurable environment factors will help advance studies of the molecular mechanisms of gene-environment interplay.

  17. Radiation-induced nitric oxide mitigates tumor hypoxia and radioresistance in a murine SCCVII tumor model

    Energy Technology Data Exchange (ETDEWEB)

    Nagane, Masaki, E-mail: nagane@vetmed.hokudai.ac.jp [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan); Yasui, Hironobu, E-mail: yassan@vetmed.hokudai.ac.jp [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan); Yamamori, Tohru, E-mail: yamamorit@vetmed.hokudai.ac.jp [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan); Zhao, Songji, E-mail: zsi@med.hokudai.ac.jp [Department of Tracer Kinetics and Bioanalysis, Graduate School of Medicine, Hokkaido University, Sapporo (Japan); Kuge, Yuji, E-mail: kuge@med.hokudai.ac.jp [Central Institute of Isotope Science, Hokkaido University, Sapporo (Japan); Tamaki, Nagara, E-mail: natamaki@med.hokudai.ac.jp [Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Sapporo (Japan); Kameya, Hiromi, E-mail: kameya@affrc.go.jp [Food Safety Division, National Food Research Institute, Tsukuba (Japan); Nakamura, Hideo, E-mail: naka@science-edu.org [Department of Chemistry, Hokkaido University of Education, Hakodate (Japan); Fujii, Hirotada, E-mail: hgfujii@sapmed.ac.jp [Center for Medical Education, Sapporo Medical University, Sapporo (Japan); Inanami, Osamu, E-mail: inanami@vetmed.hokudai.ac.jp [Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo (Japan)

    2013-08-02

    Highlights: •IR-induced NO increased tissue perfusion and pO{sub 2}. •IR increased NO production in tumors without changes in the mRNA and protein levels of NOS isoforms. •NOS activity assay showed that IR upregulated eNOS activity in tumors. •IR-induced NO decreased tumor hypoxia and altered tumor radiosensitivity. -- Abstract: Tumor hypoxia, which occurs mainly as a result of inadequate tissue perfusion in solid tumors, is a well-known challenge for successful radiotherapy. Recent evidence suggests that ionizing radiation (IR) upregulates nitric oxide (NO) production and that IR-induced NO has the potential to increase intratumoral circulation. However, the kinetics of NO production and the responsible isoforms for NO synthase in tumors exposed to IR remain unclear. In this study, we aimed to elucidate the mechanism by which IR stimulates NO production in tumors and the effect of IR-induced NO on tumor radiosensitivity. Hoechst33342 perfusion assay and electron spin resonance oxymetry showed that IR increased tissue perfusion and pO{sub 2} in tumor tissue. Immunohistochemical analysis using two different hypoxic probes showed that IR decreased hypoxic regions in tumors; treatment with a nitric oxide synthase (NOS) inhibitor, L-NAME, abrogated the effects of IR. Moreover, IR increased endothelial NOS (eNOS) activity without affecting its mRNA or protein expression levels in SCCVII-transplanted tumors. Tumor growth delay assay showed that L-NAME decreased the anti-tumor effect of fractionated radiation (10 Gy × 2). These results suggested that IR increased eNOS activity and subsequent tissue perfusion in tumors. Increases in intratumoral circulation simultaneously decreased tumor hypoxia. As a result, IR-induced NO increased tumor radiosensitivity. Our study provides a new insight into the NO-dependent mechanism for efficient fractionated radiotherapy.

  18. Large animal models and new therapies for glycogen storage disease.

    Science.gov (United States)

    Brooks, Elizabeth D; Koeberl, Dwight D

    2015-05-01

    Glycogen storage diseases (GSD), a unique category of inherited metabolic disorders, were first described early in the twentieth century. Since then, the biochemical and genetic bases of these disorders have been determined, and an increasing number of animal models for GSD have become available. At least seven large mammalian models have been developed for laboratory research on GSDs. These models have facilitated the development of new therapies, including gene therapy, which are undergoing clinical translation. For example, gene therapy prolonged survival and prevented hypoglycemia during fasting for greater than one year in dogs with GSD type Ia, and the need for periodic re-administration to maintain efficacy was demonstrated in that dog model. The further development of gene therapy could provide curative therapy for patients with GSD and other inherited metabolic disorders.

  19. STTARR: a radiation treatment and multi-modal imaging facility for fast tracking novel agent development in small animal models

    International Nuclear Information System (INIS)

    Yeung, Ivan; McKee, Trevor; Jaffray, David; Hill, Richard

    2014-01-01

    Small animal models play a pivotal role in the pipeline development of novel agents and strategies in personalized cancer therapy. The Spatio-Temporal Targeting and Amplification of Radiation Response Program (STTARR) consists of an animal imaging and precision radiation facility designed to provide innovative biologic imaging and targeted radiation treatment strategies in small animals. The design is to mirror the imaging and radiation treatment facility in a modern cancer center. The STTARR features imaging equipment of small animal scale including CT, MRI, PET, SPECT, Optical devices as well as image guided irradiators. The fleet of imaging and irradiation equipment provides a platform for identification of biological targets of the specific molecular pathways that influence both tumor progression and a patient's response to radiation therapy. Examples will be given in the utilization of the imaging facilities for development in novel approaches in cancer therapy including a PET-FAZA study for hypoxia measurement in a pancreatic adenocarcinoma xenograft model. In addition, the cone-beam image guided small animal irradiator developed at our institute will also be described. The animal platform (couch) provides motion in 3 dimensions to position the animal to the isocentre of the beam. A pair of rotational arms supporting the X-ray/detector pair enables acquisition of cone-beam images of the animal which give rise to image guided precision of 0.5 mm. The irradiation energy ranges from 50 to 225 kVp at a dose rate from 10-400 cGy/min. The gantry is able to direct X-ray beam of different directions to give conformal radiation treatment to the animal. A dedicated treatment planning system is able to perform treatment planning and provide commonly used clinical metrics in the animal treatment plan. Examples will be given to highlight the use of the image guided irradiator for research of drug/irradiation regimen in animal models. (author)

  20. Establishment of animal model of dual liver transplantation in rat.

    Directory of Open Access Journals (Sweden)

    Ying Zhang

    Full Text Available The animal model of the whole-size and reduced-size liver transplantation in both rat and mouse has been successfully established. Because of the difficulties and complexities in microsurgical technology, the animal model of dual liver transplantation was still not established for twelve years since the first human dual liver transplantation has been made a success. There is an essential need to establish this animal model to lay a basic foundation for clinical practice. To study the physiological and histopathological changes of dual liver transplantation, "Y" type vein from the cross part between vena cava and two iliac of donor and "Y' type prosthesis were employed to recanalize portal vein and the bile duct between dual liver grafts and recipient. The dual right upper lobes about 45-50% of the recipient liver volume were taken as donor, one was orthotopically implanted at its original position, the other was rotated 180° sagitally and heterotopically positioned in the left upper quadrant. Microcirculation parameters, liver function, immunohistochemistry and survival were analyzed to evaluate the function of dual liver grafts. No significant difference in the hepatic microcirculatory flow was found between two grafts in the first 90 minutes after reperfusion. Light and electronic microscope showed the liver architecture was maintained without obvious features of cellular destruction and the continuity of the endothelium was preserved. Only 3 heterotopically positioned graft appeared patchy desquamation of endothelial cell, mitochondrial swelling and hepatocytes cytoplasmic vacuolization. Immunohistochemistry revealed there is no difference in hepatocyte activity and the ability of endothelia to contract and relax after reperfusion between dual grafts. Dual grafts made a rapid amelioration of liver function after reperfusion. 7 rats survived more than 7 days with survival rate of 58.3.%. Using "Y" type vein and bile duct prosthesis, we

  1. Current understanding of hypospadias: relevance of animal models.

    Science.gov (United States)

    Cunha, Gerald R; Sinclair, Adriane; Risbridger, Gail; Hutson, John; Baskin, Laurence S

    2015-05-01

    Hypospadias is a congenital abnormality of the penile urethra with an incidence of approximately 1:200-1:300 male births, which has doubled over the past three decades. The aetiology of the overwhelming majority of hypospadias remains unknown but appears to be a combination of genetic susceptibility and prenatal exposure to endocrine disruptors. Reliable animal models of hypospadias are required for better understanding of the mechanisms of normal penile urethral formation and hence hypospadias. Mice and/or rats are generally used for experimental modelling of hypospadias, however these do not fully reflect the human condition. To use these models successfully, researchers must understand the similarities a