Immunoglobulin leakiness in scid mice with CD4(+) T-cell-induced chronic colitis

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Brimnes, J; Reimann, J; Claesson, Mogens Helweg

2000-01-01

Inflammatory bowel disease in scid mice is initiated by transplantation of CD4(+) T-cells from immunocompetent syngenic donor mice. As the disease progresses, immunoglobulin (Ig)-containing cells appear in the gut lamina propria, suggesting that locally accumulating Ig may play a role in disease ...

Low pH immobilizes and kills human leukocytes and prevents transmission of cell-associated HIV in a mouse model

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Markham Richard B

2005-09-01

Full Text Available Abstract Background Both cell-associated and cell-free HIV virions are present in semen and cervical secretions of HIV-infected individuals. Thus, topical microbicides may need to inactivate both cell-associated and cell-free HIV to prevent sexual transmission of HIV/AIDS. To determine if the mild acidity of the healthy vagina and acid buffering microbicides would prevent transmission by HIV-infected leukocytes, we measured the effect of pH on leukocyte motility, viability and intracellular pH and tested the ability of an acidic buffering microbicide (BufferGel® to prevent the transmission of cell-associated HIV in a HuPBL-SCID mouse model. Methods Human lymphocyte, monocyte, and macrophage motilities were measured as a function of time and pH using various acidifying agents. Lymphocyte and macrophage motilities were measured using video microscopy. Monocyte motility was measured using video microscopy and chemotactic chambers. Peripheral blood mononuclear cell (PBMC viability and intracellular pH were determined as a function of time and pH using fluorescent dyes. HuPBL-SCID mice were pretreated with BufferGel, saline, or a control gel and challenged with HIV-1-infected human PBMCs. Results Progressive motility was completely abolished in all cell types between pH 5.5 and 6.0. Concomitantly, at and below pH 5.5, the intracellular pH of PBMCs dropped precipitously to match the extracellular medium and did not recover. After acidification with hydrochloric acid to pH 4.5 for 60 min, although completely immotile, 58% of PBMCs excluded ethidium homodimer-1 (dead-cell dye. In contrast, when acidified to this pH with BufferGel, a microbicide designed to maintain vaginal acidity in the presence of semen, only 4% excluded dye at 10 min and none excluded dye after 30 min. BufferGel significantly reduced transmission of HIV-1 in HuPBL-SCID mice (1 of 12 infected compared to saline (12 of 12 infected and a control gel (5 of 7 infected. Conclusion These

CD4+ T lymphocytes injected into severe combined immunodeficient (SCID) mice lead to an inflammatory and lethal bowel disease

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Claesson, Mogens Helweg; Rudolphi, A; Kofoed, S

1996-01-01

Transfer of 2 x 10(5) congenic or semiallogenic purified TCR alphabeta+ CD4+ T cells to SCID mice leads to an infiltration of the recipient gut lamina propria and epithelium with a donor-derived CD4+ T cell subset which induces a lethal inflammatory bowel disease (IBD) in the recipients....... In contrast, IBD was not observed in SCID mice transplanted with unfractionated splenic cells. The earliest detectable pathological changes after CD4+ T cell transfer were proliferation and hypertrophy of the entire colonic epithelial layer, including increased mitotic activity, increased expression...... plasma cells were present in the lamina propria of both the small and large intestine. We conclude that low numbers of intraveneously transferred CD4+ T cells induce IBD in SCID mice. In the late stages of CD4+ T cell-induced IBD, the colonic lamina propria becomes infiltrated with macrophages...

scid mutation in mice confers hypersensitivity to ionizing radiation and a deficiency in DNA double-strand break repair

International Nuclear Information System (INIS)

Biedermann, K.A.; Sun, J.R.; Giaccia, A.J.; Tosto, L.M.; Brown, J.M.

1991-01-01

C.B-17 severe combined immunodeficient (scid) mice carry the scid mutation and are severely deficient in both T cell- and B cell-mediated immunity, apparently as a result of defective V(D)J joining of the immunoglobulin and T-cell receptor gene elements. In the present studies, we have defined the tissue, cellular, and molecular basis of another characteristic of these mice: their hypersensitivity to ionizing radiation. Bone marrow stem cells, intestinal crypt cells, and epithelial skin cells from scid mice are 2- to 3-fold more sensitive when irradiated in situ than are congenic BALB/c or C.B-17 controls. Two independently isolated embryo fibroblastic scid mouse cell lines display similar hypersensitivities to gamma-rays. In addition, these cell lines are sensitive to cell killing by bleomycin, which also produces DNA strand breaks, but not by the DNA crosslinking agent mitomycin C or UV irradiation. Measurement of the rejoining of gamma-ray-induced DNA double-strand breaks by pulsed-field gel electrophoresis indicates that these animals are defective in this repair system. This suggests that the gamma-ray sensitivity of the scid mouse fibroblasts could be the result of reduced repair of DNA double-strand breaks. Therefore, a common factor may participate in both the repair of DNA double-strand breaks as well as V(D)J rejoining during lymphocyte development. This murine autosomal recessive mutation should prove extremely useful in fundamental studies of radiation-induced DNA damage and repair

CD4+ T regulatory cells from the colonic lamina propria of normal mice inhibit proliferation of enterobacteria-reactive, disease-inducing Th1-cells from scid mice with colitis

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Gad, M; Brimnes, J; Claesson, Mogens Helweg

2003-01-01

Adoptive transfer of CD4+ T cells into scid mice leads to a chronic colitis in the recipients. The transferred CD4+ T cells accumulate in the intestinal lamina propria (LP), express an activated Th1 phenotype and proliferate vigorously when exposed ex vivo to enteric bacterial antigens. As LP CD4......+ T cells from normal BALB/c mice do not respond to enteric bacterial antigens, we have investigated whether colonic LP-derived CD4+ T cells from normal mice suppress the antibacterial response of CD4+ T cells from scid mice with colitis. LP-derived CD4+ T cells cocultured with bone marrow......-derived dendritic cells effectively suppress the antibacterial proliferative response of CD4+ T cells from scid mice with colitis. The majority of these LP T-reg cells display a nonactivated phenotype and suppression is independent of antigen exposure, is partly mediated by soluble factor(s) different from IL-10...

IL-2 receptor γ-chain molecule is critical for intestinal T-cell reconstitution in humanized mice.

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Denton, P W; Nochi, T; Lim, A; Krisko, J F; Martinez-Torres, F; Choudhary, S K; Wahl, A; Olesen, R; Zou, W; Di Santo, J P; Margolis, D M; Garcia, J V

2012-09-01

Intestinal immune cells are important in host defense, yet the determinants for human lymphoid homeostasis in the intestines are poorly understood. In contrast, lymphoid homeostasis has been studied extensively in mice, where the requirement for a functional common γ-chain molecule has been established. We hypothesized that humanized mice could offer insights into human intestinal lymphoid homeostasis if generated in a strain with an intact mouse common γ-chain molecule. To address this hypothesis, we used three mouse strains (non-obese diabetic (NOD)/severe-combined immunodeficient (SCID) (N/S); NOD/SCID γ-chain(-/-) (NSG); and Rag2(-/-) γ-chain(-/-) (DKO)) and two humanization techniques (bone marrow liver thymus (BLT) and human CD34(+) cell bone marrow transplant of newborn mice (hu)) to generate four common types of humanized mice: N/S-BLT, NSG-BLT, NSG-hu, and DKO-hu mice. The highest levels of intestinal human T cells throughout the small and large intestines were observed in N/S-BLT mice, which have an intact common γ-chain molecule. Furthermore, the small intestine lamina propria T-cell populations of N/S-BLT mice exhibit a human intestine-specific surface phenotype. Thus, the extensive intestinal immune reconstitution of N/S-BLT mice was both quantitatively and qualitatively better when compared with the other models tested such that N/S-BLT mice are well suited for the analysis of human intestinal lymphocyte trafficking and human-specific diseases affecting the intestines.

Increased intracellular Th1 cytokines in scid mice with inflammatory bowel disease

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Bregenholt, S; Claesson, Mogens Helweg

1998-01-01

Severe combined immunodeficient (scid) mice engrafted with small pieces of full thickness gut wall from immunocompetent syngenic donors develop a chronic and lethal colitis. Lymphocytes from the lamina propria of engrafted mice were analyzed for phorbol ester/ionomycin-induced cytokine production...... by intracellular staining. A 4-5-fold increase in the fraction of IFN-gamma-producing CD4+ lamina propria T cells was found in moderately and severely diseased mice when compared to healthy congenic C.B-17 control mice. The number of IL-2-producing T cells was increased by approximately 2-fold when comparing mice...... suffering from severe disease to healthy control mice. The fraction of TNF-alpha positive CD4+ T cells was increased by a factor of two in both moderately and severely diseased mice. When analyzing Th2 cytokines, it was found that the levels of IL-4-producing CD4+ T cells was not altered in diseased animals...

Lol p I-specific IgE and IgG synthesis by peripheral blood mononuclear cells from atopic subjects in SCID mice.

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Gagnon, R; Boutin, Y; Hébert, J

1995-06-01

The development of an animal model representative of the in vivo situation of human atopic diseases is always of interest for a better understanding of IgE production and regulation. Along these lines, mice with severe combined immunodeficiency (SCID mice) engrafted with lymphocytes from atopic subjects might be a suitable model for such studies. This study aims to analyze the production of Lol p I-specific IgE and IgG antibodies in SCID mice after transplantation of human peripheral blood mononuclear cells from atopic patients sensitive to grass pollens and from nonatopic donors. Peripheral blood mononuclear cells were transplanted into SCID mice, which were then challenged with Lol p I, and antibody responses (IgG and IgE) were analyzed over a 6-week period. Total IgG antibody was measured in each mouse serum after transplantation. Also, most mice (regardless of whether donors were atopic) that were challenged with Lol p I produced specific IgG antibody. Total IgE antibody production was observed only in mice grafted with cells from atopic patients. Lol p I-specific IgE antibodies were also produced after immunization with Lol p I. Although IgG antibody/response tended to plateau, the IgE antibody response increased until it peaked and declined thereafter. Interferon-gamma was detected in sera from mice producing IgE antibody, which supports a possible role of interferon-gamma in the decrease of IgE response. This study suggests that the SCID mouse model could represent an interesting approach to studying specific, total IgG and IgE antibody production, and ultimately their regulation.

Effects of HIV-1 on Cognition in Humanized NSG Mice

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Akhter, Sidra Pervez

Host species specificity of human immunodeficiency virus (HIV) creates a challenge to study the pathology, diagnostic tools, and therapeutic agents. The closely related simian immunodeficiency virus and studies of neurocognitive impairments on transgenic animals expressing partial viral genome have significant limitations. The humanized mice model provides a small animal system in which a human immune system can be engrafted and immunopathobiology of HIV-1 infection can be studied. However, features of HIV-associated neurocognitive disorders (HAND) were not evaluated in this model. Open field activity test was selected to characterize behavior of original strain NOD/scid-IL-2Rgammac null (NSG) mice, effects of engraftment of human CD34+ hematopoietic stem cells (HSCs) and functional human immune system (huNSG), and finally, investigate the behavior changes induced by chronic HIV-1 infection. Long-term infected HuNSG mice showed the loss of working memory and increased anxiety in the open field. Additionally, these animals were utilized for evaluation of central nervous system metabolic and structural changes. Detected behavioral abnormalities are correlated with obtained neuroimaging and histological abnormalities published.

Reconstitution of immunodeficient SCID/beige mice with human cells: Applications in preclinical studies

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Thomsen, Mogens; Galvani, Sylvain; Canivet, Cindy; Kamar, Nassim; Boehler, Torsten

2008-01-01

Experimental studies of the in vivo behaviour of human cells and tissues have become possible with the development of immunodeficient mice strains. Such mice accept readily allogeneic or xenogeneic grafts, including grafts of human cells or tissues, without rejection. In this review we describe different immunodeficient mouse strains that have been used for reconstitution by human immune cells. We subsequently go through the experience that we and others have had with reconstitution, and mention the adverse effects, in particular xenogeneic graft versus host reactions. The use of haematopoietic stem cells avoids such reactions but the immunological reconstitution may take several months. We then report the use of immunodeficient mice for the study of chronic vascular rejection of human mesenteric arteries due to cellular or humoral alloreaction. We have shown that SCID/beige mice grafted with a human artery at the place of the aorta developed a thickening of the intima of the human artery after 5-6 weeks, when they were reconstituted with spleen cells from another human donor. The thickening is mainly due to a proliferation of smooth muscle cells. The same type of lesion developed if they received injection of antibodies towards HLA class I antigens. The arteries of the mouse did not develop any lesion. The arterial lesions closely resembled those seen after clinical organ transplantation. Mice that received spleen cells from the same human donor developed little or no lesions. An important aspect of this experimental transplantation model is the possibility to test drugs that may be used in clinical transplantation. In recent experiments we have shown that novel immunosuppressive drugs can inhibit the hyperproliferation of smooth muscle cells in vitro. Preclinical testing in reconstituted SCID/beige mice grafted with human arteries will permit the evaluation of the potential use of these drugs to prevent chronic vascular rejection. The model also allows

HIV-1 infection, response to treatment and establishment of viral latency in a novel humanized T cell-only mouse (TOM) model.

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Honeycutt, Jenna B; Wahl, Angela; Archin, Nancie; Choudhary, Shailesh; Margolis, David; Garcia, J Victor

2013-10-24

The major targets of HIV infection in humans are CD4⁺ T cells. CD4⁺ T cell depletion is a hallmark of AIDS. Previously, the SCID-hu thy/liv model was used to study the effect of HIV on thymopoeisis in vivo. However, these mice did not develop high levels of peripheral T cell reconstitution and required invasive surgery for infection and analysis. Here, we describe a novel variant of this model in which thy/liv implantation results in systemic reconstitution with human T cells in the absence of any other human hematopoietic lineages. NOD/SCID-hu thy/liv and NSG-hu thy/liv mice were created by implanting human fetal thymus and liver tissues under the kidney capsule of either NOD/SCID or NSG mice. In contrast to NOD/SCID-hu thy/liv mice that show little or no human cells in peripheral blood or tissues, substantial systemic human reconstitution occurs in NSG-hu thy/liv. These mice are exclusively reconstituted with human T cells (i.e. T-cell only mice or TOM). Despite substantial levels of human T cells no signs of graft-versus-host disease (GVHD) were noted in these mice over a period of 14 months. TOM are readily infected after parenteral exposure to HIV-1. HIV replication is sustained in peripheral blood at high levels and results in modest reduction of CD4⁺ T cells. HIV-1 replication in TOM responds to daily administration of combination antiretroviral therapy (ART) resulting in strong suppression of virus replication as determined by undetectable viral load in plasma. Latently HIV infected resting CD4⁺ T cells can be isolated from suppressed mice that can be induced to express HIV ex-vivo upon activation demonstrating the establishment of latency in vivo. NSG-hu thy/liv mice are systemically reconstituted with human T cells. No other human lymphoid lineages are present in these mice (i.e. monocytes/macrophages, B cells and DC are all absent). These T cell only mice do not develop GVHD, are susceptible to HIV-1 infection and can efficiently maintain virus

Effect of Agaricus blazei Murrill extract on HT-29 human colon cancer cells in SCID mice in vivo.

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Wu, Ming-Fang; Chen, Yung-Liang; Lee, Mei-Hui; Shih, Yung-Luen; Hsu, Yu-Ming; Tang, Ming-Chu; Lu, Hsu-Feng; Tang, Nou-Ying; Yang, Su-Tso; Chueh, Fu-Shin; Chung, Jing-Gung

2011-01-01

Agaricus blazei Murrill (ABM) popularly known as 'Cogumelo do Sol' in Brazil, or 'Himematsutake' in Japan, is a mushroom native to Brazil and widely cultivated in Japan for its medicinal uses and is now considered one of the most important edible and culinary-medicinal biotechnological species. This study is the first tumor growth model to evaluate the amelioratory effect of ABM extract using HT-29 human colon cancer cells in severe combined immunodeficiency (SCID) mice. Forty SCID mice were inoculated with HT-29 cells to induce tumor formation and were then divided into four groups. All the four groups (control, low, medium and high concentration treatment) of mice were separately orally administered 0 mg, 1.125 mg, 4.5 mg or 45 mg ABM extract daily. After six weeks of treatment, 8 out of the 40 mice had not survived including one mouse which scored +++ (tumor up to 15 mm diameter) and four mice which scored ++++ (tumor over 15 mm diameter) in the control group and three mice which scored ++++ on the low-dose ABM treatment. After high- or medium-dose treatment, all ten mice in each group survived. The oral administration of ABM does not prevent tumor growth, as shown by increased tumor mass, but compared with the control group, the tumor mass seems to grow more slowly depending on the ABM dose.

Splenic T helper cell type 1 cytokine profile and extramedullary haematopoiesis in severe combined immunodeficient (scid) mice with inflammatory bowel disease (IBD)

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Bregenholt, S; Claesson, Mogens Helweg

1998-01-01

Scid mice develop a severe, chronic, and lethal IBD 3-6 months after engraftment of gut wall from immunocompetent congenic donors, induced by donor-derived CD4+ T cells migrating from the graft. We have investigated intracellular T-helper type 1 (Th1) cytokines in the spleens of gut wall-transpla......Scid mice develop a severe, chronic, and lethal IBD 3-6 months after engraftment of gut wall from immunocompetent congenic donors, induced by donor-derived CD4+ T cells migrating from the graft. We have investigated intracellular T-helper type 1 (Th1) cytokines in the spleens of gut wall...

Hemopoietic stem-cell compartment of the SCID mouse: Double-exponential survival curve after γ irradiation

International Nuclear Information System (INIS)

Taniguchi, Satoshi; Hirabayashi, Yoko; Inoue, Tohru; Kanisawa, Masayoshi; Sasaki, Hideki; Komatsu, Kenshi; Mori, K.J.

1993-01-01

It has been reported that SCID (severe combined immunodeficiency, scid/scid) mice are more radiosensitive than normal mice. In the present studies, graded doses of radiation were given to bone marrow cells from SCID mice, and double-exponential survival curves were observed for day-9 and day-12 colony-forming units in the spleen (CFU-S). Single-exponential curves were found for SCID CFU in in vitro assays for granulocyte/macrophage-CFUs and erythroid burst-forming units, as reported elsewhere. Since the size of this more resistant fraction seems to decrease with stem-cell maturation, the finding implies that this fraction is a primitive subpopulation of the stem-cell compartment. The mean lethal dose (D 0 ), however, of this less sensitive SCID CFU-S is much less than the D 0 of regular CFU-S in normal littermates. Spleen colonies produced by SCID bone marrow were relatively small and abortive. The size of these colonies decreased nearly exponentially with increasing doses of radiation. These colonies produced by the sensitive fraction have disappeared, being killed by a relatively low dose of radiation. This observation might account for the high lymphomagenesis arising from primitive hemopoietic stem cells in SCID mice, because the smallness of the colonies suggests that there is unrepaired or misrepaired damage. Furthermore, this less sensitive fraction might be a source of the open-quotes leakyclose quotes change of T and B cells, possibly due to the induction of an equivocal repair system which appears in the later stages of life in the SCID mice. 34 refs., 5 figs., 3 tabs

Cytotoxic reactivity of gut lamina propria CD4+ alpha beta T cells in SCID mice with colitis

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Bonhagen, K; Thoma, S; Bland, P

1996-01-01

Polyclonal, mucosa-seeking memory/effector CD4+ T cells containing a large fraction of blasts activated in situ accumulate in the gut lamina propria of severe-combined immunodeficient (SCID) mice developing colitis after CD4+ T cell transplantation. CD4+ T cells isolated from different repopulated...

Human LT-alpha-mediated resistance to autoimmune diabetes is induced in NOD, but not NOD-scid, mice and abrogated by IL-12.

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Miyaguchi, S; Satoh, J; Takahashi, K; Sakata, Y; Nakazawa, T; Miyazaki, J; Toyota, T

2001-01-01

Systemic administration of human lymphotoxin-alpha (hLT-alpha) made NOD mice resistant not only to spontaneous autoimmune type 1 diabetes mellitus but also to cyclophosphamide (CY)-induced diabetes and diabetes transfer by diabetic NOD spleen cells (triple resistance). In this study we analyzed the mechanisms of hLT-alpha-induced resistance, focusing on (1) hLT-alpha-induced resistance in the pancreatic beta cell, (2) CY-resistant suppressor cells, (3) suppression of induction or function of effector cells for beta cell destruction, or (4) others. To examine the first possibility in vitro, a NOD-derived beta cell line (MIN6N) was pretreated with hLT-alpha and then mixed with diabetic NOD spleen cells and MIN6N cell viability was measured. Treatment with hLT-alpha did not protect MIN6N cells but rather enhanced cytotoxicity. Next NOD-scid mice were pretreated with hLT-alpha and then transferred with diabetic NOD spleen. All the recipients developed diabetes. These results excluded the first possibility. The second possibility was also excluded by a cotransfer experiment, in which diabetic NOD spleen cells were cotransferred to NOD-scid mice with nontreated or hLT-alpha-treated nondiabetic NOD spleens. There was no significant difference in diabetes incidence between the two groups. To observe the third possibility, spleen cells of hLT-alpha-treated triple-resistant NOD mice were transferred to NOD-scid mice. Diabetes developed in the recipients, although the onset of diabetes was slightly delayed. Finally, hLT-alpha-treated triple-resistant NOD mice developed diabetes 1 week after daily IL-12 treatment. In summary, hLT-alpha administration made NOD mice resistant to effector cells for beta cell destruction. This resistance was induced in NOD, but not in NOD-scid, mice, indicating that lymphocytes were obligatory for the resistance. However, it was not mediated by transferable suppressor cells. Because effector cells were present in hLT-alpha-treated NOD spleen and

Establishment of Demodex canis on canine skin engrafted onto scid-beige mice.

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Caswell, J L; Yager, J A; Barta, J R; Parker, W

1996-12-01

A small animal model of canine demodicosis is described. Normal canine skin was engrafted onto scid (severe combined immunodeficient)-beige mice, which lack functional B and T lymphocytes and have reduced natural killer cell activity. The xenografts were later infected with Demodex canis collected from a dog with demodicosis. At 30-112 days following infection, mites were seen histologically in the canine hair follicles of the engrafted skin. Demodex canis adults, nymphs, larvae, and eggs were present in samples macerated in sodium hydroxide. Mite infestations could not be demonstrated in the mouse skin, nor were mites passed from the infected graft to uninfected skin grafts on in-contact mice. This model may be utilized to assess the efficacy of miticidal treatments, to evaluate the importance of specific components of the immune response, and to study the biology of D. canis.

Therapeutic efficacy of human hepatocyte transplantation in a SCID/uPA mouse model with inducible liver disease.

Directory of Open Access Journals (Sweden)

Donna N Douglas

2010-02-01

Full Text Available Severe Combined Immune Deficient (SCID/Urokinase-type Plasminogen Activator (uPA mice undergo liver failure and are useful hosts for the propagation of transplanted human hepatocytes (HH which must compete with recipient-derived hepatocytes for replacement of the diseased liver parenchyma. While partial replacement by HH has proven useful for studies with Hepatitis C virus, complete replacement of SCID/uPA mouse liver by HH has never been achieved and limits the broader application of these mice for other areas of biomedical research. The herpes simplex virus type-1 thymidine kinase (HSVtk/ganciclovir (GCV system is a powerful tool for cell-specific ablation in transgenic animals. The aim of this study was to selectively eliminate murine-derived parenchymal liver cells from humanized SCID/uPA mouse liver in order to achieve mice with completely humanized liver parenchyma. Thus, we reproduced the HSVtk (vTK/GCV system of hepatic failure in SCID/uPA mice.In vitro experiments demonstrated efficient killing of vTK expressing hepatoma cells after GCV treatment. For in vivo experiments, expression of vTK was targeted to the livers of FVB/N and SCID/uPA mice. Hepatic sensitivity to GCV was first established in FVB/N mice since these mice do not undergo liver failure inherent to SCID/uPA mice. Hepatic vTK expression was found to be an integral component of GCV-induced pathologic and biochemical alterations and caused death due to liver dysfunction in vTK transgenic FVB/N and non-transplanted SCID/uPA mice. In SCID/uPA mice with humanized liver, vTK/GCV caused death despite extensive replacement of the mouse liver parenchyma with HH (ranging from 32-87%. Surprisingly, vTK/GCV-dependent apoptosis and mitochondrial aberrations were also localized to bystander vTK-negative HH.Extensive replacement of mouse liver parenchyma by HH does not provide a secure therapeutic advantage against vTK/GCV-induced cytotoxicity targeted to residual mouse hepatocytes

A radiolabeled antibody targeting CD123+ leukemia stem cells – initial radioimmunotherapy studies in NOD/SCID mice engrafted with primary human AML

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Jeffrey V. Leyton

2015-01-01

Full Text Available Radioimmunotherapy (RIT with anti-CD123 monoclonal antibody CSL360 modified with nuclear translocation sequence (NLS peptides and labeled with the Auger electron-emitter, 111In (111In-NLS-CSL360 was studied in the prevalent NOD/SCID mouse AML engraftment assay. Significant decreases in CD123+ leukemic cells and impairment of leukemic stem cell self-renewal were achieved with high doses of RIT. However, NOD/SCID mice were very radiosensitive to these doses. At low non-toxic treatment doses, 111In-NLS-CSL360 demonstrated a trend towards improved survival associated with decreased spleen/body weight ratio, an indicator of leukemia burden, and almost complete eradication of leukemia from the bone marrow in some mice.

Genetics of SCID

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Cossu Fausto

2010-11-01

Full Text Available Abstract Human SCID (Severe Combined Immunodeficiency is a prenatal disorder of T lymphocyte development, that depends on the expression of numerous genes. The knowledge of the genetic basis of SCID is essential for diagnosis (e.g., clinical phenotype, lymphocyte profile and treatment (e.g., use and type of pre-hematopoietic stem cell transplant conditioning. Over the last years novel genetic defects causing SCID have been discovered, and the molecular and immunological mechanisms of SCID have been better characterized. Distinct forms of SCID show both common and peculiar (e.g., absence or presence of nonimmunological features aspects, and they are currently classified into six groups according to prevalent pathophysiological mechanisms: impaired cytokine-mediated signaling; pre-T cell receptor defects; increased lymphocyte apoptosis; defects in thymus embryogenesis; impaired calcium flux; other mechanisms. This review is the updated, extended and largely modified translation of the article "Cossu F: Le basi genetiche delle SCID", originally published in Italian language in the journal "Prospettive in Pediatria" 2009, 156:228-238.

Poliomyelitis in MuLV-infected ICR-SCID mice after injection of basement membrane matrix contaminated with lactate dehydrogenase-elevating virus.

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Carlson Scholz, Jodi A; Garg, Rohit; Compton, Susan R; Allore, Heather G; Zeiss, Caroline J; Uchio, Edward M

2011-10-01

The arterivirus lactate dehydrogenase-elevating virus (LDV) causes life-long viremia in mice. Although LDV infection generally does not cause disease, infected mice that are homozygous for the Fv1(n) allele are prone to develop poliomyelitis when immunosuppressed, a condition known as age-dependent poliomyelitis. The development of age-dependent poliomyelitis requires coinfection with endogenous murine leukemia virus. Even though LDV is a common contaminant of transplantable tumors, clinical signs of poliomyelitis after inadvertent exposure to LDV have not been described in recent literature. In addition, LDV-induced poliomyelitis has not been reported in SCID or ICR mice. Here we describe the occurrence of poliomyelitis in ICR-SCID mice resulting from injection of LDV-contaminated basement membrane matrix. After exposure to LDV, a subset of mice presented with clinical signs including paresis, which was associated with atrophy of the hindlimb musculature, and tachypnea; in addition, some mice died suddenly with or without premonitory signs. Mice presenting within the first 6 mo after infection had regions of spongiosis, neuronal necrosis and astrocytosis of the ventral spinal cord, and less commonly, brainstem. Axonal degeneration of ventral roots prevailed in more chronically infected mice. LDV was identified by RT-PCR in 12 of 15 mice with typical neuropathology; positive antiLDV immunolabeling was identified in all PCR-positive animals (n = 7) tested. Three of 8 mice with neuropathology but no clinical signs were LDV negative by RT-PCR. RT-PCR yielded murine leukemia virus in spinal cords of all mice tested, regardless of clinical presentation or neuropathology.

Genome-wide Gene Expression Profiling of SCID Mice with T-cell-mediated Colitis

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Brudzewsky, D.; Pedersen, A. E.; Claesson, M. H.

2009-01-01

Inflammatory bowel disease (IBD) is a multifactorial disorder with an unknown aetiology. The aim of this study is to employ a murine model of IBD to identify pathways and genes, which may play a key role in the pathogenesis of IBD and could be important for discovery of new disease markers in human...... and colitis mice, and among these genes there is an overrepresentation of genes involved in inflammatory processes. Some of the most significant genes showing higher expression encode S100A proteins and chemokines involved in trafficking of leucocytes in inflammatory areas. Classification by gene clustering...... based on the genes with the significantly altered gene expression corresponds to two different levels of inflammation as established by the histological scoring of the inflamed rectum. These data demonstrate that this SCID T-cell transfer model is a useful animal model for human IBD and can be used...

HTLV-1 Infection and Neuropathogenesis in the Context of Rag1-/-γc-/- (RAG1-Hu) and BLT Mice.

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Ginwala, Rashida; Caruso, Breanna; Khan, Zafar K; Pattekar, Ajinkya; Chew, Glen M; Corley, Michael J; Loonawat, Ronak; Jacobson, Steven; Sreedhar, Sreesha; Ndhlovu, Lishomwa C; Jain, Pooja

2017-09-01

To date, the lack of a suitable small animal model has hindered our understanding of Human T-cell lymphotropic virus (HTLV)-1 chronic infection and associated neuropathogenesis defined as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The host immune response plays a critical role in the outcome of HTLV-1 infection, which could be better tested in the context of humanized (hu) mice. Thus, we employ here the Balb/c-Rag1 -/- γc -/- or Rag1 as well as Bone marrow-Liver-Thymic (BLT) mouse models for engraftment of human CD34 + hematopoietic stem cells. Flow cytometry and histological analyses confirmed reconstitution of Rag1 and BLT mice with human immune cells. Following HTLV-1 infection, proviral load (PVL) was detected in the blood of Rag-1 and BLT hu-mice as early as 2 weeks post-infection (wpi) with sustained elevation in the subsequent weeks followed by Tax expression. Additionally, infection was compared between adult and neonatal Rag1 mice with both PVL and Tax expression considerably higher in the adult Rag1 mice as compared to the neonates. Establishment of peripheral infection led to lymphocytic infiltration with concomitant Tax expression and resulting myelin disruption within the central nervous system of infected mice. In addition, up-regulation in the expression of several immune checkpoint mediators such as programmed cell death-1 (PD-1), T-cell Ig and ITIM domain (TIGIT), and T cell Ig and mucin domain-3 protein (Tim-3) were observed on CD8 + T cells in various organs including the CNS of infected hu-mice. Collectively, these studies represent the first attempt to establish HTLV-1 neuropathogenesis in the context of Rag-1 and BLT hu-mice as potential novel tools for understanding HTLV-1 neuropathogenesis and testing of novel therapies such as immune checkpoint blockade in the amelioration of chronic HTLV-1 infection.

Paradoxical effects of Auger electron-emitting 111In-DTPA-NLS-CSL360 radioimmunoconjugates on hCD45+ cells in the bone marrow and spleen of leukemia-engrafted NOD/SCID or NRG mice

International Nuclear Information System (INIS)

Bergstrom, Dane; Leyton, Jeffrey V.; Zereshkian, Arman; Chan, Conrad; Cai, Zhongli; Reilly, Raymond M.

2016-01-01

Introduction: 111 In-DTPA-NLS-CSL360 radioimmunoconjugates (RIC) recognize the overexpression of the interleukin-3 receptor α-subchain (CD123) relative to the β-subchain (CD131) on leukemia stem cells (LSC). Our aim was to study Auger electron radioimmunotherapy (RIT) of acute myeloid leukemia (AML) with 111 In-DTPA-NLS-CSL360 in non-obese diabetic severe combined immunodeficiency (NOD/SCID) mice or NOD-Rag1 null IL2rγ null (NRG) mice engrafted with CD123 + human AML-5 cells. Methods: The toxicity of three doses of 111 In-DTPA-NLS-CSL360 (3.3–4.8 MBq; 11–15 μg each) injected i.v. every two weeks was studied in non-engrafted NOD/SCID or NRG mice pre-treated with 200 cGy of γ-radiation required for AML engraftment. Engraftment efficiency of (1–5) × 10 6 cells AML-5 cells inoculated i.v. into NOD/SCID or NRG mice was assessed by flow cytometric analysis for human CD45 + (hCD45 + ) cells in the bone marrow (BM) and spleen. AML-5 engrafted mice were treated with two or three doses (3.7 MBq; 10 μg each) every two weeks of 111 In-DTPA-NLS-CSL360, non-specific 111 In-DTPA-NLS-hIgG, unlabeled CSL360 (10 μg) or normal saline. The percentage of hCD45 + cells in the BM and spleen were measured at one week after completion of treatment. Results: 111 In-DTPA-NLS-CSL360 in combination with 200 cGy of γ-radiation caused an initial transient decrease in body weight in NOD/SCID but not in NRG mice. There were no hematological, liver or kidney toxicities. The spleen exhibited 13-fold lower engraftment efficiency than the BM in NOD/SCID mice inoculated with 1 × 10 6 cells but both organs were highly (>85%) engrafted in NRG mice. Unexpectedly, 111 In-DTPA-NLS-CSL360 or non-specific 111 In-DTPA-NLS-hIgG caused a paradoxical 1.5-fold increase (P < 0.0001) in the proportion of hCD45 + cells in the BM of NOD/SCID mice compared to normal saline treated mice. 111 In-DTPA-NLS-CSL360 reduced hCD45 + cells in the spleen by 3.0-fold compared to 111 In-DTPA-NLS-hIgG (P = 0

Accumulation of immunoglobulin-containing cells in the gut mucosa and presence of faecal immunoglobulin in severe combined immunodeficient (scid) mice with T cell-induced inflammatory bowel disease (IBD)

DEFF Research Database (Denmark)

Bregenholt, S; Brimnes, J; Reimann, J

1998-01-01

and IgG2b were found to accumulate in colon segments displaying the most severe histopathology, including inflammatory cellular infiltration, epithelial hyperplasia and ulcerative lesions. Compared with colon segments of normal C.B-17 mice, the lesional scid colon shows increased levels of cells positive...

The majority of lamina propria CD4(+) T-cells from scid mice with colitis undergo Fas-mediated apoptosis in vivo

DEFF Research Database (Denmark)

Bregenholt, S; Petersen, T R; Claesson, Mogens Helweg

2001-01-01

We have previously shown that adoptively transferred CD4(+) T-cells mediate an chronic colitis in severe combined immune deficient (scid) mice. Colitis is accompanied by activation and apoptosis of Fas ligand and TNF-alpha expressing CD4(+) T-cells in the diseased colonic lamina propria (Eur. J....... Immunol. 28:3655 (1998)). Here we investigate the apoptosis-inducing mechanism in these lamina propria infiltrating CD4(+) T-cells. We observe that freshly isolated lamina propria CD4(+) T-cells can kill Fas transfected P815 mastocytoma cells in a TCR/CD3 redirected chromium-release assay, but do...... not express TNF-alpha mediated cytotoxicity. Pre-incubation of the isolated lamina propria CD4(+) T-cells with an anti-FasL antiserum partially blocked killing of the Fas transfected target cells, indicating a role for the Fas-FasL system in the killing process. Treatment of scid mice with colitis with anti-Fas...

Enhanced efficacy of gemcitabine in combination with anti-CD20 monoclonal antibody against CD20+ non-Hodgkin's lymphoma cell lines in vitro and in scid mice

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Jin Fang

2005-08-01

Full Text Available Abstract Background Despite exciting new targeted therapeutics against non-Hodgkin's lymphoma (NHL, chemotherapy remains a cornerstone of therapy. While purine nucleoside analogs have significant activity in low grade NHL, the pyrimidine nucleoside analog gemcitabine has been less extensively studied, but has important activity. Use of the anti-CD20 monoclonal antibody rituximab in combination with chemotherapy for B-NHL is becoming prevalent in clinical practice, but has not been extensively studied in pre-clinical models. Methods We have tested the activity of gemcitabine ± rituximab in vitro and in scid/human NHL xenograft models. We used two t(14;18+, CD20+ follicular B cell NHL cell lines, DoHH2 a transformed NHL line and WSU-FSCCL isolated from pleural fluid of a patient with indolent NHL. Results Gemcitabine is cytotoxic to DoHH2 and WSU-FSCCL cells in vitro, and the IC50 is 2–3 fold lower in the presence of rituximab. Apoptosis is also enhanced in the presence of rituximab. Clearance of NHL cells from ascites in scid mice is prolonged by the combination, as compared with either agent alone. Most importantly, survival of scid mice bearing human NHL cells is significantly prolonged by the combination of gemcitabine + rituximab. Conclusion Based on our pre-clinical data showing prolonged survival of mice bearing human lymphoma cell line xenografts after treatment with gemcitabine + anti-CD20 antibody, this combination, expected to have non-overlapping toxicity profiles, should be explored in clinical trials.

Spontaneous lung metastasis formation of human Merkel cell carcinoma cell lines transplanted into scid mice.

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Knips, Jill; Czech-Sioli, Manja; Spohn, Michael; Heiland, Max; Moll, Ingrid; Grundhoff, Adam; Schumacher, Udo; Fischer, Nicole

2017-07-01

Merkel cell carcinoma (MCC) is an aggressive skin cancer entity that frequently leads to rapid death due to its high propensity to metastasize. The etiology of most MCC cases is linked to Merkel cell polyomavirus (MCPyV), a virus which is monoclonally integrated in up to 95% of tumors. While there are presently no animal models to study the role of authentic MCPyV infection on transformation, tumorigenesis or metastasis formation, xenograft mouse models employing engrafted MCC-derived cell lines (MCCL) represent a promising approach to study certain aspects of MCC pathogenesis. Here, the two MCPyV-positive MCC cell lines WaGa and MKL-1 were subcutaneously engrafted in scid mice. Engraftment of both MCC cell lines resulted in the appearance of circulating tumor cells and metastasis formation, with WaGa-engrafted mice showing a significantly shorter survival time as well as increased numbers of spontaneous lung metastases compared to MKL-1 mice. Interestingly, explanted tumors compared to parental cell lines exhibit an upregulation of MCPyV sT-Antigen expression in all tumors, with WaGa tumors showing significantly higher sT-Antigen expression than MKL-1 tumors. RNA-Seq analysis of explanted tumors and parental cell lines furthermore revealed that in the more aggressive WaGa tumors, genes involved in inflammatory response, growth factor activity and Wnt signalling pathway are significantly upregulated, suggesting that sT-Antigen is the driver of the observed differences in metastasis formation. © 2017 UICC.

scid Thymocytes with TCRbeta gene rearrangements are targets for the oncogenic effect of SCL and LMO1 transgenes.

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Chervinsky, D S; Lam, D H; Melman, M P; Gross, K W; Aplan, P D

2001-09-01

SCL and LMO1 were both discovered by virtue of their activation by chromosomaltranslocation in patients with T-cell acute lymphoblastic leukemia (T-ALL). Overexpression of SCL and LMO1 in the thymus of transgenic mice leads to T-ALL at a young age. scid (severe combined immunodeficient) mice are unable to efficiently recombine antigen receptor genes and consequently display a developmental block at the CD4-CD8- to CD4+CD8+ transition. To test the hypothesis that this developmental block would protect SCL/LMO1 transgenic mice from developing T-ALL, we crossed the SCL and LMO1 transgenes onto a scid background. The age of onset for T-ALL in the SCL/LMO1/scid mice was significantly delayed (P < 0.001) compared with SCL/LMO1/wild-type mice. Intriguingly, all of the SCL/LMO1/scid malignancies displayed clonal, in-frame TCRbeta gene rearrangements. Taken together, these findings suggest that the "leaky" scid thymocyte that undergoes a productive TCRbeta gene rearrangement is susceptible to the oncogenic action of SCL and LMO1 and additionally suggests that TCRbeta gene rearrangements may be required for the oncogenic action of SCL and LMO1.

Murine scid cells complement ataxia-telangiectasia cells and show a normal port-irradiation response of DNA synthesis

International Nuclear Information System (INIS)

Komatsu, K.; Yoshida, M.; Okumura, Y.

1993-01-01

The murine severe combined immunodeficient mutation (scid) is characterized by a lack of both B and T cells, due to a deficit in lymphoid variable-(diversity)-joining (V(D)J) rearrangement. Scid cells are highly sensitive to both radiation-induced killing and chromosomal aberrations. Significantly reduced D 0 and n values were demonstrated in scid cells and were similar to ataxia-telangiectasia (AT) cells (a unique human disease conferring whole body radiosensitivity). However, the kinetics of DNA synthesis after irradiation were different between the two cell types. In contrast with the radioresistant DNA synthesis of AT cells, DNA synthesis of scid cells was markedly inhibited after irradiation. The existence of different mutations was also supported by evidence of complementation in somatic cell hybrids between scid cells and AT cells. Results indicate that the radiobiological character of scid is similar to AT but is presumably caused by different mechanisms. (author)

Intratibial injection of human multiple myeloma cells in NOD/SCID IL-2Rγ(null mice mimics human myeloma and serves as a valuable tool for the development of anticancer strategies.

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Julia Schueler

Full Text Available BACKGROUND: We systematically analyzed multiple myeloma (MM cell lines and patient bone marrow cells for their engraftment capacity in immunodeficient mice and validated the response of the resulting xenografts to antimyeloma agents. DESIGN AND METHODS: Using flow cytometry and near infrared fluorescence in-vivo-imaging, growth kinetics of MM cell lines L363 and RPMI8226 and patient bone marrow cells were investigated with use of a murine subcutaneous bone implant, intratibial and intravenous approach in NOD/SCID, NOD/SCID treated with CD122 antibody and NOD/SCID IL-2Rγ(null mice (NSG. RESULTS: Myeloma growth was significantly increased in the absence of natural killer cell activity (NSG or αCD122-treated NOD/SCID. Comparison of NSG and αCD122-treated NOD/SCID revealed enhanced growth kinetics in the former, especially with respect to metastatic tumor sites which were exclusively observed therein. In NSG, MM cells were more tumorigenic when injected intratibially than intravenously. In NOD/SCID in contrast, the use of juvenile long bone implants was superior to intratibial or intravenous cancer cell injection. Using the intratibial NSG model, mice developed typical disease symptoms exclusively when implanted with human MM cell lines or patient-derived bone marrow cells, but not with healthy bone marrow cells nor in mock-injected animals. Bortezomib and dexamethasone delayed myeloma progression in L363- as well as patient-derived MM cell bearing NSG. Antitumor activity could be quantified via flow cytometry and in vivo imaging analyses. CONCLUSIONS: Our results suggest that the intratibial NSG MM model mimics the clinical situation of the disseminated disease and serves as a valuable tool in the development of novel anticancer strategies.

Pretransplant mobilization with granulocyte colony-stimulating factor improves B-cell reconstitution by lentiviral vector gene therapy in SCID-X1 mice.

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Huston, Marshall W; Riegman, Adriaan R A; Yadak, Rana; van Helsdingen, Yvette; de Boer, Helen; van Til, Niek P; Wagemaker, Gerard

2014-10-01

Hematopoietic stem cell (HSC) gene therapy is a demonstrated effective treatment for X-linked severe combined immunodeficiency (SCID-X1), but B-cell reconstitution and function has been deficient in many of the gene therapy treated patients. Cytoreductive preconditioning is known to improve HSC engraftment, but in general it is not considered for SCID-X1 since the poor health of most of these patients at diagnosis and the risk of toxicity preclude the conditioning used in standard bone marrow stem cell transplantation. We hypothesized that mobilization of HSC by granulocyte colony-stimulating factor (G-CSF) should create temporary space in bone marrow niches to improve engraftment and thereby B-cell reconstitution. In the present pilot study supplementing our earlier preclinical evaluation (Huston et al., 2011), Il2rg(-/-) mice pretreated with G-CSF were transplanted with wild-type lineage negative (Lin(-)) cells or Il2rg(-/-) Lin(-) cells transduced with therapeutic IL2RG lentiviral vectors. Mice were monitored for reconstitution of lymphocyte populations, level of donor cell chimerism, and antibody responses as compared to 2 Gy total body irradiation (TBI), previously found effective in promoting B-cell reconstitution. The results demonstrate that G-CSF promotes B-cell reconstitution similar to low-dose TBI and provides proof of principle for an alternative approach to improve efficacy of gene therapy in SCID patients without adverse effects associated with cytoreductive conditioning.

Restoration of human B-cell differentiation into NOD-SCID mice engrafted with gene-corrected CD34+ cells isolated from Artemis or RAG1-deficient patients.

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Lagresle-Peyrou, Chantal; Benjelloun, Fatine; Hue, Christophe; Andre-Schmutz, Isabelle; Bonhomme, Delphine; Forveille, Monique; Beldjord, Kheira; Hacein-Bey-Abina, Salima; De Villartay, Jean-Pierre; Charneau, Pierre; Durandy, Anne; Fischer, Alain; Cavazzana-Calvo, Marina

2008-02-01

Severe combined immunodeficiency (SCID) caused by mutation of the recombination-activating gene 1 (RAG1) or Artemis gene lead to the absence of B- and T-cell differentiation. The only curative treatment is allogeneic bone marrow (BM) transplantation, which displays a high survival rate when an HLA compatible donor is available but has a poorer prognosis when the donor is partially compatible. Consequently, gene therapy may be a promising alternative strategy for these diseases. Here, we report that lentiviral gene-corrected BM CD34(+) cells (isolated from Artemis- or RAG1-deficient patients) sustain human B-cell differentiation following injection into non-obese diabetic/SCID (NOD-SCID) mice previously infused with anti-interleukin-2 receptor beta chain monoclonal antibody. In most of the mice BM, engrafted with Artemis-transduced cells, human B-cell differentiation occurred until the mature stage. The B cells were functional as human immunoglobulin M (IgM) was present in the serum. Following injection with RAG1-transduced cells, human engraftment occurred in vivo but B-cell differentiation until the mature stage was less frequent. However, when it occurred, it was always associated with human IgM production. This overall approach represents a useful tool for evaluating gene transfer efficiency in human SCID forms affecting B-cell development (such as Artemis deficiency) and for testing new vectors for improving in vivo RAG1 complementation.

Germline mutation rates at tandem repeat loci in DNA-repair deficient mice

International Nuclear Information System (INIS)

Barber, Ruth C.; Miccoli, Laurent; Buul, Paul P.W. van; Burr, Karen L.-A.; Duyn-Goedhart, Annemarie van; Angulo, Jaime F.; Dubrova, Yuri E.

2004-01-01

Mutation rates at two expanded simple tandem repeat (ESTR) loci were studied in the germline of non-exposed and irradiated severe combined immunodeficient (scid) and poly(ADP-ribose) polymerase (PARP-1 -/- ) deficient male mice. Non-exposed scid and PARP -/- male mice showed considerably elevated ESTR mutation rates, far higher than those in wild-type isogenic mice and other inbred strains. The irradiated scid and PARP-1 -/- male mice did not show any detectable increases in their mutation rate, whereas significant ESTR mutation induction was observed in the irradiated wild-type isogenic males. ESTR mutation spectra in the scid and PARP-1 -/- strains did not differ from those in the isogenic wild-type strains. Considering these data and the results of previous studies, we propose that a delay in repair of DNA damage in scid and PARP-1 -/- mice could result in replication fork pausing which, in turn, may affect ESTR mutation rate in the non-irradiated males. The lack of mutation induction in irradiated scid and PARP-1 -/- can be explained by the high cell killing effects of irradiation on the germline of deficient mice

A trade-off in replication in mosquito versus mammalian systems conferred by a point mutation in the NS4B protein of dengue virus type 4

International Nuclear Information System (INIS)

Hanley, Kathryn A.; Manlucu, Luella R.; Gilmore, Lara E.; Blaney, Joseph E.; Hanson, Christopher T.; Murphy, Brian R.; Whitehead, Stephen S.

2003-01-01

An acceptable live-attenuated dengue virus vaccine candidate should have low potential for transmission by mosquitoes. We have identified and characterized a mutation in dengue virus type 4 (DEN4) that decreases the ability of the virus to infect mosquitoes. A panel of 1248 mutagenized virus clones generated previously by chemical mutagenesis was screened for decreased replication in mosquito C6/36 cells but efficient replication in simian Vero cells. One virus met these criteria and contained a single coding mutation: a C-to-U mutation at nucleotide 7129 resulting in a Pro-to-Leu change in amino acid 101 of the nonstructural 4B gene (NS4B P101L). This mutation results in decreased replication in C6/36 cells relative to wild-type DEN4, decreased infectivity for mosquitoes, enhanced replication in Vero and human HuH-7 cells, and enhanced replication in SCID mice implanted with HuH-7 cells (SCID-HuH-7 mice). A recombinant DEN4 virus (rDEN4) bearing this mutation exhibited the same set of phenotypes. Addition of the NS4B P101L mutation to rDEN4 bearing a 30 nucleotide deletion (Δ30) decreased the ability of the double-mutant virus to infect mosquitoes but increased its ability to replicate in SCID-HuH-7 mice. Although the NS4B P101L mutation decreases infectivity of DEN4 for mosquitoes, its ability to enhance replication in SCID-HuH-7 mice suggests that it might not be advantageous to include this specific mutation in an rDEN4 vaccine. The opposing effects of the NS4B P101L mutation in mosquito and vertebrate systems suggest that the NS4B protein is involved in maintaining the balance between efficient replication in the mosquito vector and the human host

A link between double-strand break-related repair and V(D)J recombination: the scid mutation

International Nuclear Information System (INIS)

Hendrickson, E.A.; Qin, X.Q.; Bump, E.A.; Schatz, D.G.; Oettinger, M.; Weaver, D.T.

1991-01-01

We show here that mammalian site-specific recombination and DNA-repair pathways share a common factor. The effects of DNA-damaging agents on cell lines derived from mice homozygous for the scid (severe combined immune deficiency) mutation were studied. Surprisingly, all scid cell lines exhibited a profound hypersensitivity to DNA-damaging agents that caused double-strand breaks (x-irradiation and bleomycin) but not to other chemicals that caused single-strand breaks or cross-links. Neutral filter elution assays demonstrated that the x-irradiation hypersensitivity could be correlated with a deficiency in repairing double-strand breaks. These data suggest that the scid gene product is involved in two pathways: DNA repair of random double-strand breaks and the site-specific and lymphoid-restricted variable-(diversity)-joining [V(D)J] DNA rearrangement process. We propose that the scid gene product performs a similar function in both pathways and may be a ubiquitous protein

Renal Protective Effect of Xiao-Chai-Hu-Tang on Diabetic Nephropathy of Type 1-Diabetic Mice

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Chun-Ching Lin

2012-01-01

Full Text Available Xiao-Chai-Hu-Tang (XCHT, a traditional Chinese medicine formula consisting of seven medicinal plants, is used in the treatment of various diseases. We show here that XCHT could protect type-1 diabetic mice against diabetic nephropathy, using streptozotocin (STZ-induced diabetic mice and high-glucose (HG-exposed rat mesangial cell (RMC as models. Following 4 weeks of oral administration with XCHT, renal functions and renal hypertrophy significantly improved in the STZ-diabetic mice, while serum glucose was only moderately reduced compared to vehicle treatment. Treatment with XCHT in the STZ-diabetic mice and HG-exposed RMC resulted in a decrease in expression levels of TGF-β1, fibronectin, and collagen IV, with concomitant increase in BMP-7 expression. Data from DPPH assay, DHE stain, and CM-H2DCFDA analysis indicated that XCHT could scavenge free radicals and inhibit high-glucose-induced ROS in RMCs. Taken together, these results suggest that treatment with XCHT can improve renal functions in STZ-diabetic mice, an effect that is potentially mediated through decreasing oxidative stress and production of TGF-β1, fibronectin, and collagen IV in the kidney during development of diabetic nephropathy. XCHT, therefore merits further investigation for application to improve renal functions in diabetic disorders.

Tumour necrosis factor-alpha (TNF-alpha) transcription and translation in the CD4+ T cell-transplanted scid mouse model of colitis

DEFF Research Database (Denmark)

Williams, A M; Whiting, C V; Bonhagen, K

1999-01-01

The adoptive transfer of activated CD4+ alpha/beta T cell blasts from the spleens of immunocompetent C.B-17+/+ or BALB/cdm2 mice into C.B-17scid/scid (scid) mice induces a colitis in the scid recipient within 8 weeks, which progresses to severe disease within 16 weeks. T cells isolated from......-labelled riboprobes were used. The prominent myeloid cell infiltrate in diseased tissues comprised F4/80+, Mac-l+ macrophages, neutrophils, dendritic cells and activated macrophages. TNF-alpha transcription and translation were associated with activated macrophages in the lamina propria. Activated macrophages...

Establishment of Orthotopic Xuanwei Lung Cancer SCID Mouse Model 
and Analysis of Biological Properties

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Yongchun ZHOU

2012-08-01

Full Text Available Background and objective The incidence of Xuanwei lung cancer ranks first in China, and its pathogenesis requires in-depth investigation. This study aims to establish an orthotopic Xuanwei lung cancer severe combined immunodeficiency (SCID mouse model and to provide a basic experimental platform for further study. Methods The Xuanwei lung cancer cell line XWLC-05 was inoculated into the lung tissue of SCID mice in high and low doses. The tumor formation rates, tumor characteristics, spontaneous metastases, and survival times of the mice were observed, taking a subcutaneously transplanted tumor as control. Results The tumor formation rates of the orthotopic transplantation of lung cancer cells in high and low doses were 81% and 83%, respectively, among which mice in the high-dose group appeared cachectic on day 13. Extensive invasion and adhesion were observed in the contralateral lung and thoracic cavity, but no distant metastasis was exhibited. Mice with low-dose cells in the orthotopic transplantation group appeared cachectic and distant metastasis occurred on day 25. The tumor formation rates in the subcutaneous inoculation group by the high and low doses of cells were 100% and 94.5%, respectively, and no distant metastasis was observed. The rate of metastasis within the orthotopic transplantation group and between the orthotopic and subcutaneous inoculation groups showed a significant difference (P<0.05. A significant difference was indicated by the survival rate within and between the groups (P<0.001. Conclusion We successfully established an orthotopic XWLC SCID mouse model, which lays the foundation for a more in-depth study.

Atypical radiation response of SCID cells

Science.gov (United States)

Chawapun, Nisa

Murine SCID (severe combined immune deficiency) cells are well known for their defect in DNA double-strand break repair and in variable(diversity)joining [V(D)J] recombination due to a mutation in a catalytic subunit of DNA-dependent protein kinase (DNA-PKcs). As a consequence, scid cells are hypersensitive to ionizing radiation. The present study showed that asynchronous populations of scid cells were about two-fold more sensitive than Balb/c with respect to cell killing and the defect in scid cells was corrected by complementation with human chromosome 8. Analysis of the survival of synchronized populations as a function of the cell cycle revealed that while scid cells were hypersensitive in all cell cycle phases compared to wild-type cells, this hypersensitivity is even more pronounced in G1 phase. The hypersensitivity reduced as the cells progressed into S phase suggested that homologous recombination repair plays a role. The results imply that there are at least two pathways for the repair of DSB DNA, consistent with a model previously proposed by others. The scid cells were also more sensitive to UVC light (254 nm) killing as compared to wild type cells by clonogenic survival. Using a host cell reactivation (HCR) assay to study the nucleotide excision repair (NER) which is the major repair pathway for UV-photoproducts, the results showed that NER in scid cells was not as efficient as CB- 17. This suggests that DNA-PK is involved in NER as well as non-homologous end-joining (NHEJ) DSB repair which is responsible for ionizing radiation sensitivity in scid cells. Repair in scid cells was not totally absent as shown by low dose rate sparing of cell killing after exposure to 137Cs γ-rays at dose rate of 0.6 cGy/h, 1.36 cGy/h, 6 cGy/h as compared to high dose rate at 171 cGy/min, although this phenomenon could be explained partly by proliferation. However, for radiation induced transformation, no significant dose rate effect was seen. A plot of transformation

The effect of PBL and film showing, frequent quizzes and lecture-based method on short-term performance of dentistry students

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Sadr Lahijani M.S

2004-01-01

Full Text Available Background: Advocates have proposed that frequent testing increases the effectiveness of instruction by encouraging learners to study and review more often. It has also been argued that in this way, student errors can be identified and corrected earlier and good performance can be recognized, leading to more positive attitudes toward learning process. In problem-based learning (PBL, medical students reportedly take a more active role in learning and have better recall than students in a conventional learning environment. The hypothetical benefits of a PBL and studentbased environment and use of films in the class are the development of self-learning and problem-solving skills and enhancement of knowledge and motivation. Purpose: To examine the effect of combination of PBL method and film showing on the short-term performance of dentistry students and to compare it with lecture-based method and frequent quizzes. Methods: All students of 3 years (from 2000 till 2002 that had theoretical endodontic course (part 1 participated in this descriptive-analytic study. The scores of final examinations of this course were obtained from their files. Data were analyzed by SPSS software & ANOVA. Results: The results showed that by changing the way of learning (PBL and film showing in 2001, there was a statistical difference between scores of the students of 2000 and 2001. Also there was a statistical difference with the students’ scores in 2002- the group with frequent quizzes. Conclusion: The variables such as changing the way of learning, using different methods in teaching, showing scientific films in class or, as a whole, active learning have significant effects on the results of final examination. Key Words: PBL, lecture based method, education, frequent quizzes

PBL as a Tool for Staff Development in the Educational Transformation towards PBL

DEFF Research Database (Denmark)

Du, Xiangyun; Kolmos, Anette; Qvist, Palle

2007-01-01

Abstract Worldwide, the philosophy of problem based and project based learning (PBL) has been implemented as educational models in diverse practice of teaching and learning. Recent years have witnessed more and more educational transformations towards PBL. Despite the diversity of approaches...... and practices in the process of organizational transformation, staff development remains one of key elements in the transformation process in order to teach staff new PBL practice.. A growing body of literature discussing the role of facilitation in PBL, implementation of PBL at different levels in educational...... practice, PBL online; however, little has been documented on the practice of staff development in PBL, especially through online education in the form of PBL. This paper presents the experiences and reflections of using PBL online as a strategy for staff development based on the practice...

Cellular radiosensitivity in human severe-combined-immunodeficiency (SCID) syndromes

International Nuclear Information System (INIS)

Sproston, Anthony R.M.; West, Catharine M.L.; Hendry, Jolyon H.

1997-01-01

Purpose: The aim of the work was to establish to what extent a variety of human severe-combined-immunodeficiency (SCID) disorders are associated with in vitro cellular hypersensitivity to ionizing radiation. Materials and methods: A study was made of fibroblast strains established from individuals with adenosine deaminase deficiency, T(-)B(-) SCID, Omenn's syndrome and a SCID heterozygote. For comparison, an assessment was also made of the radiosensitivity of a series of fibroblast strains derived from: normal donors, a patient with ataxia-telangiectasia (A-T) and an A-T heterozygote. Radiosensitivity was determined using a clonogenic assay following both high (HDR) and low (LDR) dose-rate irradiation. Results: Following HDR irradiation, the fibroblast strains derived from the different human SCID disorders displayed a wide range of radiosensitivity: the adenosine deaminase deficiency cells were similar in radiosensitivity to normal fibroblasts, T(-)B(-) cells were as hypersensitive to radiation as A-T cells and the Omenn's syndrome cells showed intermediate radiosensitivity. However, whereas all four normal cell strains studied showed significant LDR sparing, none of the SCID fibroblasts did. Conclusions: These data indicate that human SCID is variable in terms of radiosensitivity depending on the particular defect. In addition, the lack of LDR sparing of radiation-induced damage suggests the involvement of some form(s) of DNA repair defect in all the human SCID syndromes

Possible reduction of hepatoma formation by Smmu 7721 cells in SCID mice and metastasis formation by B16F10 melanoma cells in C57BL/6 mice by Agaricus blazei murill extract.

Science.gov (United States)

Wu, Ming-Fang; Lu, Hsu-Feng; Hsu, Yu-Ming; Tang, Ming-Chu; Chen, Hsueh-Chin; Lee, Ching-Sung; Yang, Yi-Yuan; Yeh, Ming-Yang; Chung, Hsiung-Kwang; Huang, Yi-Ping; Wu, Chih-Chung; Chung, Jing-Gung

2011-01-01

Agaricus blazei Murill extract (ABM) has been reported to possess antitumor effects. In this study, the role of ABM in tumor growth and metastasis in vivo was evaluated in experimental Smmu 7721 hepatoma cells in severe combined immunodeficiency (SCID) mice and B16F10 melanoma cells lung metastasis in C57BL/6 mice. For the tumor growth model, the size of the liver tumor mass was about 10 mm to 20 mm in the control group. In comparison with the control group, the tumor mass seem to grow slowly with ABM treatment, especially at the high dose. For the tumor metastasis model, after a six-week treatment, the survival rates of B6 mice were 0%, 30%, 10% and 50% for control group, low, median and high concentration ABM treatment groups, respectively. The survival rate showed that pretreatment of C57BL/6 (B6) mice with ABM lengthened their lifespan after tumor cell inoculation, which supports the notion that ABM successfully reduced lung metastasis formation by B16F10 melanoma cells. The treatment effect was dependent on the concentration of ABM for tumor growth and metastasis in these models.

PBL Across Cultures

DEFF Research Database (Denmark)

asked for contributions on the following sub- themes: – Approaches to PBL – The learning process (cognitive studies) – Evaluating practice – models and approaches – Theorising practice – Management of change – Learning spaces – Teacher roles in PBL – Learning technologies for PBL – Student engagement...

Helicobacter sp. MIT 01-6451 infection during fetal and neonatal life in laboratory mice.

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Yamanaka, Hitoki; Nakanishi, Tai; Takagi, Toshikazu; Ohsawa, Makiko; Kubo, Noriaki; Yamamoto, Naoto; Takemoto, Takahira; Ohsawa, Kazutaka

2015-01-01

Helicobacter sp. MIT 01-6451 has been detected in SPF mice kept in Japan. To characterize strain MIT 01-6451, its infection route during fetal and neonatal life and effects on pregnancy were investigated using immunocompetent and immunodeficient mouse strains (BALB/c, C57BL/6, and SCID). MIT 01-6451 was detected in the uterus, vagina, and mammary glands of 50% of infected SCID mice, whereas these tissues were all negative in immunocompetent mice. No fetal infections with MIT 01-6451 were detected at 16-18 days after pregnancy in any mouse strain. In newborn mice, MIT 01-6451 was detected in intestinal tissue of C57BL/6 and SCID mice at 9-11 days after birth, but not in BALB/c mice. The IgA and IgG titers to MIT 01-6451 in sera of C57BL/6 female mice were significantly lower than those of BALB/c mice. Although no significant differences in the number of newborns per litter were observed between MIT 01-6451-infected and MIT 01-6451-free dams, the birth rate was lower in infected SCID mice than in control SCID mice. The present results indicated that MIT 01-6451 infects newborn mice after birth rather than by vertical transmission to the fetus via the placenta and that MIT 01-6451 infection shows opportunistically negative effects on the birth rate. In addition, the maternal immune response may affect infection of newborn mice with MIT 01-6451 through breast milk.

PBL3.0

DEFF Research Database (Denmark)

Zotou, Maria; Tambouris, Efthimios; Triantafyllou, Evangelia

This paper presents the PBL3.0 project that aims at enhancing Problem Based Learning (PBL) with Learning Analytics (LA) and Learning Semantics (LS) in order to produce a new educational paradigm and pilot it to produce relevant policy recommendations. To this end, the project will reach the follo......This paper presents the PBL3.0 project that aims at enhancing Problem Based Learning (PBL) with Learning Analytics (LA) and Learning Semantics (LS) in order to produce a new educational paradigm and pilot it to produce relevant policy recommendations. To this end, the project will reach...

Cooperative effect of the attenuation determinants derived from poliovirus sabin 1 strain is essential for attenuation of enterovirus 71 in the NOD/SCID mouse infection model.

Science.gov (United States)

Arita, Minetaro; Ami, Yasushi; Wakita, Takaji; Shimizu, Hiroyuki

2008-02-01

Enterovirus 71 (EV71) is a causative agent of hand, foot, and mouth disease and is also associated with serious neurological disorders. An attenuated EV71 strain [EV71(S1-3')] has been established in the cynomolgus monkey infection model; this strain contains the attenuation determinants derived from the type 1 poliovirus vaccine strain, Sabin 1 [PV1(Sabin)], in the 5' nontranslated region (NTR), 3D polymerase, and 3' NTR. In this study, we analyzed the effect of the attenuation determinants of PV1(Sabin) on EV71 infection in a NOD/SCID mouse infection model. We isolated a mouse-adapted EV71 strain [EV71(NOD/SCID)] that causes paralysis of the hind limbs in 3- to 4-week-old NOD/SCID mice by adaptation of the virulent EV71(Nagoya) strain in the brains of NOD/SCID mice. A single mutation at nucleotide 2876 that caused an amino acid change in capsid protein VP1 (change of the glycine at position 145 to glutamic acid) was essential for the mouse-adapted phenotype in NOD/SCID mice. Next, we introduced attenuation determinants derived from PV1(Sabin) along with the mouse adaptation mutation into the EV71(Nagoya) genome. In 4-week-old mice, the determinants in the 3D polymerase and 3' NTR, which are the major temperature-sensitive determinants, had a strong effect on attenuation. In contrast, the effect of individual determinants was weak in 3-week-old NOD/SCID mice, and all the determinants were required for substantial attenuation. These results suggest that a cooperative effect of the attenuation determinants of PV1(Sabin) is essential for attenuated neurovirulence of EV71.

PBL in Engineering Education

DEFF Research Database (Denmark)

PBL in Engineering Education: International Perspectives on Curriculum Change presents diverse views on the implementation of PBL from across the globe. The purpose is to exemplify curriculum changes in engineering education. Drivers for change, implementation descriptions, challenges and future...... perspectives are addressed. Cases of PBL models are presented from Singapore, Malaysia, Tunisia, Portugal, Spain and the USA. These cases are stories of thriving success that can be an inspiration for those who aim to implement PBL and change their engineering education practices. In the examples presented......, the change processes imply a transformation of vision and values of what learning should be, triggering a transition from traditional learning to PBL. In this sense, PBL is also a learning philosophy and different drivers, facing diverse challenges and involving different actors, trigger its implementation...

PBL and CDIO

DEFF Research Database (Denmark)

Edström, Kristina; Kolmos, Anette

2014-01-01

This paper compares two models for reforming engineering education, problem/project-based learning (PBL), and conceive–design–implement–operate (CDIO), identifying and explaining similarities and differences. PBL and CDIO are defined and contrasted in terms of their history, community, definition......, and that PBL and CDIO can play compatible and mutually reinforcing roles, and thus can be fruitfully combined to reform engineering education....... the communities can learn from each other. It is noted that while the two approaches share many underlying values, they only partially overlap as strategies for educational reform. The conclusions are that practitioners have much to learn from each other's experiences through a dialogue between the communities......This paper compares two models for reforming engineering education, problem/project-based learning (PBL), and conceive–design–implement–operate (CDIO), identifying and explaining similarities and differences. PBL and CDIO are defined and contrasted in terms of their history, community, definitions...

PBL in Educational Psychology

DEFF Research Database (Denmark)

Szulevicz, Thomas; Jensen, Mogens

2013-01-01

This article discusses practical and theoretical aspects related to PBL. In the first section of the article, potentials related to professional training of forthcoming educational psychologists following PBL-principles are analyzed. It is argued that PBL constitutes a good platform for creating ...

Establishment of human patient-derived endometrial cancer xenografts in NOD scid gamma mice for the study of invasion and metastasis.

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Kenji Unno

Full Text Available Most endometrial cancers are detected early and have a good prognosis, while some endometrial cancers are highly invasive, metastasize early, and respond suboptimally to therapy. Currently, appropriate model systems to study the aggressive nature of these tumors are lacking. The objective of this study was to establish a mouse xenograft model of endometrial tumors derived from patients in order to study the biological aggressive characteristics that underlie invasion and metastasis.Endometrial tumor tissue fragments (1.5 mm × 1.5 mm from patients undergoing surgery, were transplanted under the renal capsule of NOD scid gamma mice. After 6-8 weeks, tumors were excised and serially transplanted into additional mice for propagation. Immunohistochemical analysis of the tumors was done for various tumor markers.Four cases of different subtypes of endometrial cancer were grown and propagated in mice. Three of the four tumor cases invaded into the kidneys and to adjacent organs. While all tumors exhibited minimal to no staining for estrogen receptor α, progesterone receptor staining was observed for tumor grafts. In addition, levels and localization of E-cadherin, cytokeratin and vimentin varied depending on subtype. Finally, all tumor xenografts stained positively for urokinase plasminogen activator while 3 tumor xenografts, which showed invasive characteristics, stained positively for urokinase plasminogen activator receptor.Endometrial tumors transplanted under the renal capsule exhibit growth, invasion and local spread. These tumors can be propagated and used to study aggressive endometrial cancer.

Human progenitor cells rapidly mobilized by AMD3100 repopulate NOD/SCID mice with increased frequency in comparison to cells from the same donor mobilized by granulocyte colony stimulating factor

DEFF Research Database (Denmark)

Hess, David A; Bonde, Jesper; Craft, Timothy P

2007-01-01

) or purified CD34(+) cells was compared at limiting dilution into NOD/SCID mice. Human AMD3100-mobilized MNC possessed enhanced repopulating frequency in comparison to G-CSF-mobilized MNC from paired donors, and purified CD34(+) progenitors were at least as efficient as the G-CSF mobilized cells....... The frequencies of NOD/SCID repopulating cells (SRC) were 1 SRC in 8.7 x 10(6) AMD3100-mobilized MNC compared to 1 SRC in 29.0 x 10(6) G-CSF-mobilized MNC, and 1 SRC in 1.2 x 10(5) AMD3100-mobilized CD34(+) cells compared to 1 SRC in 1.8 x 10(5) G-CSF-mobilized CD34(+) cells. Hematopoietic differentiation...

Identification of PblB mediating galactose-specific adhesion in a successful Streptococcus pneumoniae clone.

Science.gov (United States)

Hsieh, Yu-Chia; Lin, Tzu-Lung; Lin, Che-Ming; Wang, Jin-Town

2015-07-21

The pneumococcal genome is variable and there are minimal data on the influence of the accessory genome on phenotype. Pneumococcal serotype 14 sequence type (ST) 46 had been the most prevalent clone causing pneumonia in children in Taiwan. A microarray was constructed using the genomic DNA of a clinical strain (NTUH-P15) of serotype 14 ST46. Using DNA hybridization, genomic variations in NTUH-P15 were compared to those of 3 control strains. Microarray analysis identified 7 genomic regions that had significant increases in hybridization signals in the NTUH-P15 strain compared to control strains. One of these regions encoded PblB, a phage-encoded virulence factor implicated (in Streptococcus mitis) in infective endocarditis. The isogenic pblB mutant decreased adherence to A549 human lung epithelial cell compared to wild-type NTUH-P15 strain (P = 0.01). Complementation with pblB restored the adherence. PblB is predicted to contain a galactose-binding domain-like region. Preincubation of NTUH-P15 with D-galactose resulted in decreases of adherence to A549 cell in a dose-dependent manner. Challenge of mice with NTUH-P15, isogenic pblB mutant and pblB complementation strains determined that PblB was required for bacterial persistence in the nasopharynx and lung. PblB, as an adhesin mediating the galactose-specific adhesion activity of pneumococci, promote pneumococcal clonal success.

Antibody repertoires in humanized NOD-scid-IL2Rγ(null mice and human B cells reveals human-like diversification and tolerance checkpoints in the mouse.

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Gregory C Ippolito

Full Text Available Immunodeficient mice reconstituted with human hematopoietic stem cells enable the in vivo study of human hematopoiesis. In particular, NOD-scid-IL2Rγ(null engrafted mice have been shown to have reasonable levels of T and B cell repopulation and can mount T-cell dependent responses; however, antigen-specific B-cell responses in this model are generally poor. We explored whether developmental defects in the immunoglobulin gene repertoire might be partly responsible for the low level of antibody responses in this model. Roche 454 sequencing was used to obtain over 685,000 reads from cDNA encoding immunoglobulin heavy (IGH and light (IGK and IGL genes isolated from immature, naïve, or total splenic B cells in engrafted NOD-scid-IL2Rγ(null mice, and compared with over 940,000 reads from peripheral B cells of two healthy volunteers. We find that while naïve B-cell repertoires in humanized mice are chiefly indistinguishable from those in human blood B cells, and display highly correlated patterns of immunoglobulin gene segment use, the complementarity-determining region H3 (CDR-H3 repertoires are nevertheless extremely diverse and are specific for each individual. Despite this diversity, preferential D(H-J(H pairings repeatedly occur within the CDR-H3 interval that are strikingly similar across all repertoires examined, implying a genetic constraint imposed on repertoire generation. Moreover, CDR-H3 length, charged amino-acid content, and hydropathy are indistinguishable between humans and humanized mice, with no evidence of global autoimmune signatures. Importantly, however, a statistically greater usage of the inherently autoreactive IGHV4-34 and IGKV4-1 genes was observed in the newly formed immature B cells relative to naïve B or total splenic B cells in the humanized mice, a finding consistent with the deletion of autoreactive B cells in humans. Overall, our results provide evidence that key features of the primary repertoire are shaped by

Engineering Students: Enhancing Employability Skills through PBL

Science.gov (United States)

H, Othman; Mat Daud K., A.; U, Ewon; Salleh B, Mohd; Omar N., H.; Baser J, Abd; Ismail M., E.; A, Sulaiman

2017-05-01

As a developing country, Malaysia faces challenging tasks to develop her economy just like many other countries. Nowadays, change involves many aspects like the economy from agriculture to manufacturing, technology from modern to more advanced ones; mindset from traditional to advanced and so on. Previous studies show that one of the major issues facing local graduates is the lack of employability skills. This problem concerns not only the government but undergraduates and institutions alike. From the pedagogical aspect, one of the more effective ways to improve this is through instructional delivery and in this case the use of Problem-based Learning (PBL). The need to adopt PBL should involved applied subjects undertaken by engineering students. Studies have shown that the use of PBL has been proven to make learning more attractive and effective. In this research, we studied the effectiveness of PBL towards enhancing employability skills among engineering undergraduates. This study adopted a combination of qualitative and quantitative approaches. Data was collected using documents analysis. Student samples comprised manufacturing engineering undergraduates from public institutions of higher learning in Malaysia. The results show that student’s employability skills can be enhanced using PBL. In addition, students become more competitive towards making them more relevance with the needs of the industry with regard to employability skills. In conclusion, PBL is a very effective catalyst towards raising the employability skills among engineering undergraduates and should be adopted in all engineering education.

Chronic Myelogenous Leukemia Cells Contribute to the Stromal Myofibroblasts in Leukemic NOD/SCID Mouse In Vivo

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Ryosuke Shirasaki

2012-01-01

Full Text Available We recently reported that chronic myelogenous leukemia (CML cells converted into myofibroblasts to create a microenvironment for proliferation of CML cells in vitro. To analyze a biological contribution of CML-derived myofibroblasts in vivo, we observed the characters of leukemic nonobese diabetes/severe combined immunodeficiency (NOD/SCID mouse. Bone marrow nonadherent mononuclear cells as well as human CD45-positive cells obtained from CML patients were injected to the irradiated NOD/SCID mice. When the chimeric BCR-ABL transcript was demonstrated in blood, human CML cells were detected in NOD/SCID murine bone marrow. And CML-derived myofibroblasts composed with the bone marrow-stroma, which produced significant amounts of human vascular endothelial growth factor A. When the parental CML cells were cultured with myofibroblasts separated from CML cell-engrafted NOD/SCID murine bone marrow, CML cells proliferated significantly. These observations indicate that CML cells make an adequate microenvironment for their own proliferation in vivo.

From PBL tutoring to PBL coaching in undergraduate medical education: an interpretative phenomenological analysis study

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Qing Wang

2016-07-01

Full Text Available Background: Coaching psychology is of increasing interest to medical educators for its potential benefits as a facilitative method in problem-based learning (PBL. However, the field lacks empirical studies that explore the lived experiences of students and tutors in the PBL coaching process. This study aimed to elicit knowledge regarding medical students’ and tutors’ experiences and perceptions of PBL coaching in the context of Chinese undergraduate medical education. Methods: The qualitative methodology of interpretative phenomenological analysis (IPA was employed. Participants comprised third year medical students (n=20 and PBL tutors (n=5 who have adopted a coaching approach in PBL for a semester. Semi-structured interviews were utilized to obtain a comprehensive understanding of their experiences of PBL coaching. Data analysis followed an iterative four-stage scheme of Biggerstaff and Thompson. Results: Six main themes emerged from diverse experiences and interpretations: 1 mindsets of coaching and learning, 2 the development of learning dispositions and capacities, 3 student group collaboration, 4 tutor–student relationships, 5 personal and professional development, and 6 challenges and difficulties in implementation. Conclusions: It could be concluded that PBL coaching is a dynamic, facilitative process that makes a particular contribution to the learning process from psychological, emotional, and social perspectives, whilst it demonstrates significant overlaps with PBL tutoring in terms of supporting students’ cognitive activities in PBL. Further research is needed to identify the barriers and challenges for medical educators to implement coaching in the PBL process.

From PBL tutoring to PBL coaching in undergraduate medical education: an interpretative phenomenological analysis study.

Science.gov (United States)

Wang, Qing; Li, Huiping; Pang, Weiguo

2016-01-01

Coaching psychology is of increasing interest to medical educators for its potential benefits as a facilitative method in problem-based learning (PBL). However, the field lacks empirical studies that explore the lived experiences of students and tutors in the PBL coaching process. This study aimed to elicit knowledge regarding medical students' and tutors' experiences and perceptions of PBL coaching in the context of Chinese undergraduate medical education. The qualitative methodology of interpretative phenomenological analysis (IPA) was employed. Participants comprised third year medical students (n=20) and PBL tutors (n=5) who have adopted a coaching approach in PBL for a semester. Semi-structured interviews were utilized to obtain a comprehensive understanding of their experiences of PBL coaching. Data analysis followed an iterative four-stage scheme of Biggerstaff and Thompson. Six main themes emerged from diverse experiences and interpretations: 1) mindsets of coaching and learning, 2) the development of learning dispositions and capacities, 3) student group collaboration, 4) tutor-student relationships, 5) personal and professional development, and 6) challenges and difficulties in implementation. It could be concluded that PBL coaching is a dynamic, facilitative process that makes a particular contribution to the learning process from psychological, emotional, and social perspectives, whilst it demonstrates significant overlaps with PBL tutoring in terms of supporting students' cognitive activities in PBL. Further research is needed to identify the barriers and challenges for medical educators to implement coaching in the PBL process.

Assessment of human MAPCs for stem cell transplantation and cardiac regeneration after myocardial infarction in SCID mice.

Science.gov (United States)

Dimomeletis, Ilias; Deindl, Elisabeth; Zaruba, Marc; Groebner, Michael; Zahler, Stefan; Laslo, Saskia M; David, Robert; Kostin, Sawa; Deutsch, Markus A; Assmann, Gerd; Mueller-Hoecker, Josef; Feuring-Buske, Michaela; Franz, Wolfgang M

2010-11-01

Clinical studies suggest that transplantation of total bone marrow (BM) after myocardial infarction (MI) is feasible and potentially effective. However, focusing on a defined BM-derived stem cell type may enable a more specific and optimized treatment. Multilineage differentiation potential makes BM-derived multipotent adult progenitor cells (MAPCs) a promising stem cell pool for regenerative purposes. We analyzed the cardioregenerative potential of human MAPCs in a murine model of myocardial infarction. Human MAPCs were selected by negative depletion of CD45(+)/glycophorin(+) BM cells and plated on fibronectin-coated dishes. In vitro, stem cells were analyzed by reverse transcription polymerase chain reaction. In vivo, we transplanted human MAPCs (5 × 10(5)) by intramyocardial injection after MI in severe combined immunodeficient (SCID) beige mice. Six and 30 days after the surgical procedure, pressure-volume relationships were investigated in vivo. Heart tissues were analyzed immunohistochemically. Reverse transcription polymerase chain reaction experiments on early human MAPC passages evidenced an expression of Oct-4, a stem cell marker indicating pluripotency. In later passages, cardiac markers (Nkx2.5, GATA4, MLC-2v, MLC-2a, ANP, cTnT, cTnI,) and smooth muscle cell markers (SMA, SM22α) were expressed. Transplantation of human MAPCs into the ischemic border zone after MI resulted in an improved cardiac function at day 6 (ejection fraction, 26% vs 20%) and day 30 (ejection fraction, 30% vs 23%). Confirmation of human MAPC marker vimentin in immunohistochemistry demonstrated that human MAPC integrated in the peri-infarct region. The proliferation marker Ki67 was absent in immunohistochemistry and teratoma formation was not found, indicating no tumorous potential of transplanted human MAPCs in the tumor-sensitive SCID model. Transplantation of human MAPCs after MI ameliorates myocardial function, which may be explained by trophic effects of human MAPCs. Lack of

Tuberculin-induced delayed-type hypersensitivity reaction in a model of hu-PBMC-SCID mice grafted with autologous skin.

Science.gov (United States)

Tsicopoulos, A.; Pestel, J.; Fahy, O.; Vorng, H.; Vandenbusche, F.; Porte, H.; Eraldi, L.; Wurtz, A.; Akoum, H.; Hamid, Q.; Wallaert, B.; Tonnel, A. B.

1998-01-01

We have developed an animal model to study human delayed-type hypersensitivity reactions. Previous studies in humans have shown after tuberculin injection the presence of a mononuclear cell infiltration, with almost no eosinophils, associated with a preferential Th-1-type cytokine profile. Human skin graft obtained from tuberculin-reactive donors was grafted onto the back of severe combined immunodeficient mice. After healing, mice were reconstituted intraperitoneally with peripheral mononuclear cells. Tuberculin and diluent were injected intradermally, and skin biopsies were performed 72 hours later. Skin grafts were divided into two parts, one for immunohistochemistry and one for in situ hybridization studies. Immunohistochemistry was performed on cryostat sections using the alkaline phosphatase anti-alkaline phosphatase technique. In the tuberculin-injected sites as compared with the diluent-injected sites, there were significant increases in the number of CD45+ pan leukocytes and CD4+, CD8+, CD45RO+ T cells but not in CD68+ monocytes/macrophages and EG2 or MBP+ eosinophils. The activation markers CD25 and HLA-DR were up-regulated in the tuberculin-injected sites. In situ hybridization was performed using 35S-labeled riboprobes for interleukin (IL)-2, interferon (IFN)-gamma, IL-4, and IL-5. After tuberculin injection, a preferential Th-1-type cytokine profile was observed with significant increases in the numbers of IL-2 and IFN-gamma mRNA-expressing cells. These results are similar to those reported after tuberculin-induced delayed-type hypersensitivity in humans, suggesting that this model might be useful to study cutaneous inflammatory reaction. Images Figure 4 PMID:9626072

Outlines of the PBL Working programme 2012; Hoofdlijnen PBL Werkprogramma 2012

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-01-15

In this note, the Netherlands Environmental Assessment Agency (PBL) sketches the outlines of its working programme for 2012. With the intended research in this working programme, PBL aims to contribute to scientific substantiation and evaluation of the Dutch cabinet's policy in a wide range of areas: environment, mobility, space, living, energy, water, food provision, nature, international collaboration, declining population, administrative reforms and international competitive position. The PBL study is aligned to three (of the six) governmental strategic knowledge themes that have been selected for this administrative period, i.e. Dealing with scarcity of resources and space; (2) the competitive position of the Netherlands; (3) Towards a new division of responsibilities among the state and society and a new balance between rights and obligations [Dutch] Het Planbureau voor de Leefomgeving (PBL) schetst in deze notitie de hoofdlijnen van zijn werkprogramma voor 2012. Met het voorgenomen onderzoek in dit werkprogramma wil het PBL bijdragen aan wetenschappelijke onderbouwing en evaluatie van het kabinetsbeleid op een breed scala aan terreinen: milieu, mobiliteit, ruimte, wonen, energie, water, voedselvoorziening, natuur, internationale samenwerking, bevolkingskrimp, decentralisatie, bestuurlijke vernieuwing en internationale concurrentiepositie. PBL-onderzoek sluit aan bij drie (van de zes) rijksbrede strategische kennisthema's die zijn gekozen voor deze kabinetsperiode, te weten: (1) Omgaan met schaarste aan ruimte en grondstoffen; (2) Het concurrentievermogen van Nederland; (3) Naar een nieuwe verantwoordelijkheidsverdeling tussen staat en samenleving en een nieuwe balans tussen rechten en plichten.

HuD Regulates Coding and Noncoding RNA to Induce APP→Aβ Processing

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Min-Ju Kang

2014-06-01

Full Text Available The primarily neuronal RNA-binding protein HuD is implicated in learning and memory. Here, we report the identification of several HuD target transcripts linked to Alzheimer’s disease (AD pathogenesis. HuD interacted with the 3′ UTRs of APP mRNA (encoding amyloid precursor protein and BACE1 mRNA (encoding β-site APP-cleaving enzyme 1 and increased the half-lives of these mRNAs. HuD also associated with and stabilized the long noncoding (lncRNA BACE1AS, which partly complements BACE1 mRNA and enhances BACE1 expression. Consistent with HuD promoting production of APP and APP-cleaving enzyme, the levels of APP, BACE1, BACE1AS, and Aβ were higher in the brain of HuD-overexpressing mice. Importantly, cortex (superior temporal gyrus from patients with AD displayed significantly higher levels of HuD and, accordingly, elevated APP, BACE1, BACE1AS, and Aβ than did cortical tissue from healthy age-matched individuals. We propose that HuD jointly promotes the production of APP and the cleavage of its amyloidogenic fragment, Aβ.

Aberrant phenotypes of transgenic mice expressing dimeric human erythropoietin

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Yun Seong-Jo

2012-01-01

Full Text Available Abstract Background Dimeric human erythropoietin (dHuEPO peptides are reported to exhibit significantly higher biological activity than the monomeric form of recombinant EPO. The objective of this study was to produce transgenic (tg mice expressing dHuEPO and to investigate the characteristics of these mice. Methods A dHuEPO-expressing vector under the control of the goat beta-casein promoter, which produced a dimer of human EPO molecules linked by a 2-amino acid peptide linker (Asp-Ile, was constructed and injected into 1-cell fertilized embryos by microinjection. Mice were screened using genomic DNA samples obtained from tail biopsies. Blood samples were obtained by heart puncture using heparinized tubes, and hematologic parameters were assessed. Using the microarray analysis tool, we analyzed differences in gene expression in the spleens of tg and control mice. Results A high rate of spontaneous abortion or death of the offspring was observed in the recipients of dHuEPO embryos. We obtained 3 founder lines (#4, #11, and #47 of tg mice expressing the dHuEPO gene. However, only one founder line showed stable germline integration and transmission, subsequently establishing the only transgenic line (#11. We obtained 2 F1 mice and 3 F2 mice from line #11. The dHuEPO protein could not be obtained because of repeated spontaneous abortions in the tg mice. Tg mice exhibited symptoms such as short lifespan and abnormal blood composition. The red blood cell count, white blood cell count, and hematocrit levels in the tg mice were remarkably higher than those in the control mice. The spleens of the tg mice (F1 and F2 females were 11- and -21-fold larger than those of the control mice. Microarray analysis revealed 2,672 spleen-derived candidate genes; more genes were downregulated than upregulated (849/764. Reverse transcriptase-polymerase chain reaction (RT-PCR and quantitative real-time PCR (qRT-PCR were used for validating the results of the microarray

PBL, Social Progress and Sustainability

DEFF Research Database (Denmark)

The IRSPBL has collected 53 contributions from 19 different countries, all compiled in this book. The contributions cover a number of relevant PBL topics such as assessment, learning outcomes, students’ engagement, management of change, curriculum and course design, PBL models, PBL application, ICT...

Cryptosporidium parvum infection in SCID mice infected with only one oocyst: qPCR assessment of parasite replication in tissues and development of digestive cancer.

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Sadia Benamrouz

Full Text Available Dexamethasone (Dex treated Severe Combined Immunodeficiency (SCID mice were previously described as developing digestive adenocarcinoma after massive infection with Cryptosporidium parvum as soon as 45 days post-infection (P.I.. We aimed to determine the minimum number of oocysts capable of inducing infection and thereby gastrointestinal tumors in this model. Mice were challenged with calibrated oocyst suspensions containing intended doses of: 1, 10, 100 or 10(5 oocysts of C. parvum Iowa strain. All administered doses were infective for animals but increasing the oocyst challenge lead to an increase in mice infectivity (P = 0.01. Oocyst shedding was detected at 7 days P.I. after inoculation with more than 10 oocysts, and after 15 days in mice challenged with one oocyst. In groups challenged with lower inocula, parasite growth phase was significantly higher (P = 0.005 compared to mice inoculated with higher doses. After 45 days P.I. all groups of mice had a mean of oocyst shedding superior to 10,000 oocyst/g of feces. The most impressive observation of this study was the demonstration that C. parvum-induced digestive adenocarcinoma could be caused by infection with low doses of Cryptosporidium, even with only one oocyst: in mice inoculated with low doses, neoplastic lesions were detected as early as 45 days P.I. both in the stomach and ileo-caecal region, and these lesions could evolve in an invasive adenocarcinoma. These findings show a great amplification effect of parasites in mouse tissues after challenge with low doses as confirmed by quantitative PCR. The ability of C. parvum to infect mice with one oocyst and to develop digestive adenocarcinoma suggests that other mammalian species including humans could be also susceptible to this process, especially when they are severely immunocompromised.

Cryptosporidium parvum infection in SCID mice infected with only one oocyst: qPCR assessment of parasite replication in tissues and development of digestive cancer.

Science.gov (United States)

Benamrouz, Sadia; Guyot, Karine; Gazzola, Sophie; Mouray, Anthony; Chassat, Thierry; Delaire, Baptiste; Chabé, Magali; Gosset, Pierre; Viscogliosi, Eric; Dei-Cas, Eduardo; Creusy, Colette; Conseil, Valerie; Certad, Gabriela

2012-01-01

Dexamethasone (Dex) treated Severe Combined Immunodeficiency (SCID) mice were previously described as developing digestive adenocarcinoma after massive infection with Cryptosporidium parvum as soon as 45 days post-infection (P.I.). We aimed to determine the minimum number of oocysts capable of inducing infection and thereby gastrointestinal tumors in this model. Mice were challenged with calibrated oocyst suspensions containing intended doses of: 1, 10, 100 or 10(5) oocysts of C. parvum Iowa strain. All administered doses were infective for animals but increasing the oocyst challenge lead to an increase in mice infectivity (P = 0.01). Oocyst shedding was detected at 7 days P.I. after inoculation with more than 10 oocysts, and after 15 days in mice challenged with one oocyst. In groups challenged with lower inocula, parasite growth phase was significantly higher (P = 0.005) compared to mice inoculated with higher doses. After 45 days P.I. all groups of mice had a mean of oocyst shedding superior to 10,000 oocyst/g of feces. The most impressive observation of this study was the demonstration that C. parvum-induced digestive adenocarcinoma could be caused by infection with low doses of Cryptosporidium, even with only one oocyst: in mice inoculated with low doses, neoplastic lesions were detected as early as 45 days P.I. both in the stomach and ileo-caecal region, and these lesions could evolve in an invasive adenocarcinoma. These findings show a great amplification effect of parasites in mouse tissues after challenge with low doses as confirmed by quantitative PCR. The ability of C. parvum to infect mice with one oocyst and to develop digestive adenocarcinoma suggests that other mammalian species including humans could be also susceptible to this process, especially when they are severely immunocompromised.

Recombinant human erythropoietin alpha improves the efficacy of radiotherapy of a human tumor xenograft, affecting tumor cells and microvessels

International Nuclear Information System (INIS)

Loevey, J.; Bereczky, B.; Gilly, R.; Kenessey, I.; Raso, E.; Simon, E.; Timar, J.; Dobos, J.; Vago, A.; Kasler, M.; Doeme, B.; Tovari, J.

2008-01-01

Background and purpose: tumor-induced anemia often occurs in cancer patients, and is corrected by recombinant human erythropoietins (rHuEPOs). Recent studies indicated that, besides erythroid progenitor cells, tumor and endothelial cells express erythropoietin receptor (EPOR) as well; therefore, rHuEPO may affect their functions. Here, the effect of rHuEPOα on irradiation in EPOR-positive human squamous cell carcinoma xenograft was tested. Material and methods: A431 tumor-bearing SCID mice were treated from the tumor implantation with rHuEPOα at human-equivalent dose. Xenografts were irradiated (5 Gy) on day 14, and the final tumor mass was measured on day 22. The systemic effects of rHuEPOα on the hemoglobin level, on tumor-associated blood vessels and on hypoxia-inducible factor-(HIF-)1α expression of the tumor xenografts were monitored. The proliferation, apoptosis and clonogenic capacity of A431 cancer cells treated with rHuEPOα and irradiation were also tested in vitro. Results: in vitro, rHuEPOα treatment alone did not modify the proliferation of EPOR-positive A431 tumor cells but enhanced the effect of irradiation on proliferation, apoptosis and clonogenic capacity. In vivo, rHuEPOα administration compensated the tumor-induced anemia in SCID mice and decreased tumoral HIF-1α expression but had no effect on tumor growth. At the same time rHuEPOα treatment significantly increased the efficacy of radiotherapy in vivo (tumor weight of 23.9 ± 4.7 mg and 34.9 ± 4.6 mg, respectively), mediated by increased tumoral blood vessel destruction. Conclusion: rHuEPOα treatment may modulate the efficacy of cancer radiotherapy not only by reducing systemic hypoxia and tumoral HIF-1α expression, but also by destroying tumoral vessels. (orig.)

SCID

African Journals Online (AJOL)

within days of birth and no high-throughput screening test for SCID is currently available.7 Better prevention of maternal and infant HIV infection and more rapid access to HAART for those infected is likely to reduce the infant population at risk of disseminated BCG disease.3. Conclusion. Vaccination strategies attempt to ...

Neonatal bone marrow transplantation of ADA-deficient SCID mice results in immunologic reconstitution despite low levels of engraftment and an absence of selective donor T lymphoid expansion.

Science.gov (United States)

Carbonaro, Denise A; Jin, Xiangyang; Cotoi, Daniel; Mi, Tiejuan; Yu, Xiao-Jin; Skelton, Dianne C; Dorey, Frederick; Kellems, Rodney E; Blackburn, Michael R; Kohn, Donald B

2008-06-15

Adenosine deaminase (ADA)-deficient severe combined immune deficiency (SCID) may be treated by allogeneic hematopoietic stem cell transplantation without prior cytoreductive conditioning, although the mechanism of immune reconstitution is unclear. We studied this process in a murine gene knockout model of ADA-deficient SCID. Newborn ADA-deficient pups received transplants of intravenous infusion of normal congenic bone marrow, without prior cytoreductive conditioning, which resulted in long-term survival, multisystem correction, and nearly normal lymphocyte numbers and mitogenic proliferative responses. Only 1% to 3% of lymphocytes and myeloid cells were of donor origin without a selective expansion of donor-derived lymphocytes; immune reconstitution was by endogenous, host-derived ADA-deficient lymphocytes. Preconditioning of neonates with 100 to 400 cGy of total body irradiation before normal donor marrow transplant increased the levels of engrafted donor cells in a radiation dose-dependent manner, but the chimerism levels were similar for lymphoid and myeloid cells. The absence of selective reconstitution by donor T lymphocytes in the ADA-deficient mice indicates that restoration of immune function occurred by rescue of endogenous ADA-deficient lymphocytes through cross-correction from the engrafted ADA-replete donor cells. Thus, ADA-deficient SCID is unique in its responses to nonmyeloablative bone marrow transplantation, which has implications for clinical bone marrow transplantation or gene therapy.

Problem-based learning (PBL) and public health: an initial exploration of perceptions of PBL in Vietnam.

Science.gov (United States)

Grisham, John W; Martiniuk, Alexandra L C; Negin, Joel; Wright, E P

2015-03-01

Worldwide interest in problem-based learning (PBL) has grown in past decades. This article aims to evaluate the perceived effectiveness, appropriateness, benefits, and challenges attributed to the use of PBL in public health education in Vietnam with a view to providing recommendations for curricular design and future policy. Teachers at 2 universities in Hanoi participated in group interviews, and students from these 2 universities completed Likert-style questionnaires. Students and teachers regarded PBL positively. However, there was consensus that hybrid models that used PBL alongside other methods are probably the most beneficial for public health education in Vietnam. Teachers discussed the educational and systematic advantages and difficulties associated with PBL. Themes arising from this analysis may be helpful in guiding future research-namely, regarding the application of PBL in low- and middle-income countries and in public health. Further exploration of the use of PBL hybrid models is discussed. © 2012 APJPH.

Eradication of Human Hepatic and Pulmonary Melanoma Metastases in SCID Mice by Antibody--Interleukin 2 Fusion Proteins

Science.gov (United States)

Becker, Jurgen C.; Pancook, James D.; Gillies, Stephen D.; Mendelsohn, John; Reisfeld, Ralph A.

1996-04-01

Antibody--cytokine fusion proteins combine the unique targeting ability of antibodies with the multifunctional activity of cytokines. Here, we demonstrate the therapeutic efficacy of such constructs for the treatment of hepatic and pulmonary metastases of different melanoma cell lines. Two antibody--interleukin 2 (IL-2) fusion proteins, ch225-IL2 and ch14.18-IL2, constructed by fusion of a synthetic sequence coding for human IL-2 to the carboxyl end of the Cγ 1 gene of the corresponding antibodies, were tested for their therapeutic efficacy against xenografted human melanoma in vivo. Tumorspecific fusion proteins completely inhibited the growth of hepatic and pulmonary metastases in C.B-17 scid/scid mice previously reconstituted with human lymphokine-activated killer cells, whereas treatment with combinations of the corresponding antibodies plus recombinant IL-2 only reduced the tumor load. Even when treatment with fusion proteins was delayed up to 8 days after inoculation of tumor cells, it still resulted in complete eradication of micrometastases that were established at that time point. Selection of tumor cell lines expressing or lacking the targeted antigen of the administered fusion protein proved the specificity of the observed antitumor effect. Biodistribution analysis demonstrated that the tumorspecific fusion protein accumulated not only in subcutaneous tumors but also in lungs and livers affected with micrometastases. Survival times of animals treated with the fusion protein were more than doubled as compared to those treated with the combination of the corresponding antibody plus IL-2. Our data demonstrate that an immunotherapeutic approach using cytokines targeted by antibodies to tumor sites has potent effects against disseminated human melanoma.

Modeling Human Leukemia Immunotherapy in Humanized Mice

Directory of Open Access Journals (Sweden)

Jinxing Xia

2016-08-01

Full Text Available The currently available human tumor xenograft models permit modeling of human cancers in vivo, but in immunocompromised hosts. Here we report a humanized mouse (hu-mouse model made by transplantation of human fetal thymic tissue plus hematopoietic stem cells transduced with a leukemia-associated fusion gene MLL-AF9. In addition to normal human lymphohematopoietic reconstitution as seen in non-leukemic hu-mice, these hu-mice showed spontaneous development of B-cell acute lymphoblastic leukemia (B-ALL, which was transplantable to secondary recipients with an autologous human immune system. Using this model, we show that lymphopenia markedly improves the antitumor efficacy of recipient leukocyte infusion (RLI, a GVHD-free immunotherapy that induces antitumor responses in association with rejection of donor chimerism in mixed allogeneic chimeras. Our data demonstrate the potential of this leukemic hu-mouse model in modeling leukemia immunotherapy, and suggest that RLI may offer a safe treatment option for leukemia patients with severe lymphopenia.

PBL and the Postmodern Condition

DEFF Research Database (Denmark)

Ravn, Ole; Jensen, Annie Aarup

2016-01-01

. Through discussions of this alleged condition for university curricula development we investigate its connections to the PBL-model. Some of the explored conditions highlight strong potentials for the PBL-model but the postmodern condition also raises a number of changes and challenges in relation...... to the original PBL-model as an educational setting....

Reduced phosphorylation of brain insulin receptor substrate and Akt proteins in apolipoprotein-E4 targeted replacement mice.

Science.gov (United States)

Ong, Qi-Rui; Chan, Elizabeth S; Lim, Mei-Li; Cole, Gregory M; Wong, Boon-Seng

2014-01-17

Human ApoE4 accelerates memory decline in ageing and in Alzheimer's disease. Although intranasal insulin can improve cognition, this has little effect in ApoE4 subjects. To understand this ApoE genotype-dependent effect, we examined brain insulin signaling in huApoE3 and huApoE4 targeted replacement (TR) mice. At 32 weeks, lower insulin receptor substrate 1 (IRS1) at S636/639 and Akt phosphorylation at T308 were detected in fasting huApoE4 TR mice as compared to fasting huApoE3 TR mice. These changes in fasting huApoE4 TR mice were linked to lower brain glucose content and have no effect on plasma glucose level. However, at 72 weeks of age, these early changes were accompanied by reduction in IRS2 expression, IRS1 phosphorylation at Y608, Akt phosphorylation at S473, and MAPK (p38 and p44/42) activation in the fasting huApoE4 TR mice. The lower brain glucose was significantly associated with higher brain insulin in the aged huApoE4 TR mice. These results show that ApoE4 reduces brain insulin signaling and glucose level leading to higher insulin content.

Radioprotective effect of hematopoietic growth factor gene therapy regulated by Egr-1 promoter on radiation injury of SCID mice

International Nuclear Information System (INIS)

Du Nan; Pei Xuetao; Luo Chengji; Su Yongping; Cheng Tianmin

2002-01-01

Objective: To explore the radioprotective effect of the expression of hematopoietic growth factors regulated by radio-inducible promoter on radiation injury. Methods: The human FL cDNA and EGFP cDNA were linked together with an internal ribosome entry site (IRES) and then inserted into the eukaryotic expression vector pCI-neo with the Egr-1 promoter (Egr-EF), and further transduced into bone marrow stromal cell lines HFCL (HFCL/EF). The HFCL/EF and CD34 + cells from human umbilical cord blood were transplanted i.v. one after the other into sublethally irradiated severe combined immunodeficient (SCID) mice. The number of peripheral blood WBC and human cells engrafted in recipient mice were detected by flow cytometry and CFU-GM assay. Results: In contrast to two control groups (HFCL and HFCL/F), HFCL/EF (the Egr-1 regulatory element-driven expression of FL gene therapy) resulted in a proportionally obvious increase in the number of the WBC at early stage after irradiation. Significant differences were found for CD45 + , CD34 + , CFU-GM, and nucleated cells in the bone marrow. Conclusion: Hematopoietic growth factor gene therapy regulated by radio-inducible promoter has radioprotective effect on radiation hematopoietic injury

Innovation and PBL Implementation in Higher Education-Approaches for Educational Change to PBL

DEFF Research Database (Denmark)

Li, Huichun; Stojcevski, Alex; Du, Xiangyun

2010-01-01

organizational profile. In this paper, we review three international universities from different context which are in the process of transforming their traditional education model to PBL one. We discuss their approaches of changing to PBL from three aspects: strategies, levels, as well as time.......As an innovative and promising education approach, PBL(problem and project based learning) has been adopted by various higher education institutions which are attempting to promote teaching and learning outcome, cultivate self learning and problem solving competences, as well as enhance...

Minocycline attenuates HIV-1 infection and suppresses chronic immune activation in humanized NOD/LtsZ-scidIL-2Rγnull mice

Science.gov (United States)

Singh, Maneesh; Singh, Pratibha; Vaira, Dolores; Amand, Mathieu; Rahmouni, Souad; Moutschen, Michel

2014-01-01

More than a quarter of a century of research has established chronic immune activation and dysfunctional T cells as central features of chronic HIV infection and subsequent immunodeficiency. Consequently, the search for a new immunomodulatory therapy that could reduce immune activation and improve T-cell function has been increased. However, the lack of small animal models for in vivo HIV study has hampered progress. In the current study, we have investigated a model of cord blood haematopoietic progenitor cells (CB-HPCs) -transplanted humanized NOD/LtsZ-scidIL-2Rγnull mice in which progression of HIV infection is associated with widespread chronic immune activation and inflammation. Indeed, HIV infection in humanized NSG mice caused up-regulation of several T-cell immune activation markers such as CD38, HLA-DR, CD69 and co-receptor CCR5. T-cell exhaustion markers PD-1 and CTLA-4 were found to be significantly up-regulated on T cells. Moreover, increased plasmatic levels of lipopolysaccharide, sCD14 and interleukin-10 were also observed in infected mice. Treatment with minocycline resulted in a significant decrease of expression of cellular and plasma immune activation markers, inhibition of HIV replication and improved T-cell counts in HIV-infected humanized NSG mice. The study demonstrates that minocycline could be an effective, low-cost adjunctive treatment to regulate chronic immune activation and replication of HIV. PMID:24409837

Alterations in the adenosine metabolism and CD39/CD73 adenosinergic machinery cause loss of Treg cell function and autoimmunity in ADA-deficient SCID.

Science.gov (United States)

Sauer, Aisha V; Brigida, Immacolata; Carriglio, Nicola; Hernandez, Raisa Jofra; Scaramuzza, Samantha; Clavenna, Daniela; Sanvito, Francesca; Poliani, Pietro L; Gagliani, Nicola; Carlucci, Filippo; Tabucchi, Antonella; Roncarolo, Maria Grazia; Traggiai, Elisabetta; Villa, Anna; Aiuti, Alessandro

2012-02-09

Adenosine acts as anti-inflammatory mediator on the immune system and has been described in regulatory T cell (Treg)-mediated suppression. In the absence of adenosine deaminase (ADA), adenosine and other purine metabolites accumulate, leading to severe immunodeficiency with recurrent infections (ADA-SCID). Particularly ADA-deficient patients with late-onset forms and after enzyme replacement therapy (PEG-ADA) are known to manifest immune dysregulation. Herein we provide evidence that alterations in the purine metabolism interfere with Treg function, thereby contributing to autoimmune manifestations in ADA deficiency. Tregs isolated from PEG-ADA-treated patients are reduced in number and show decreased suppressive activity, whereas they are corrected after gene therapy. Untreated murine ADA(-/-) Tregs show alterations in the plasma membrane CD39/CD73 ectonucleotidase machinery and limited suppressive activity via extracellular adenosine. PEG-ADA-treated mice developed multiple autoantibodies and hypothyroidism in contrast to mice treated with bone marrow transplantation or gene therapy. Tregs isolated from PEG-ADA-treated mice lacked suppressive activity, suggesting that this treatment interferes with Treg functionality. The alterations in the CD39/CD73 adenosinergic machinery and loss of function in ADA-deficient Tregs provide new insights into a predisposition to autoimmunity and the underlying mechanisms causing defective peripheral tolerance in ADA-SCID.

PBL-SEE: An Authentic Assessment Model for PBL-Based Software Engineering Education

Science.gov (United States)

dos Santos, Simone C.

2017-01-01

The problem-based learning (PBL) approach has been successfully applied to teaching software engineering thanks to its principles of group work, learning by solving real problems, and learning environments that match the market realities. However, the lack of well-defined methodologies and processes for implementing the PBL approach represents a…

An alternant method to the traditional NASA hindlimb unloading model in mice.

Science.gov (United States)

Ferreira, J Andries; Crissey, Jacqueline M; Brown, Marybeth

2011-03-10

The Morey-Holton hindlimb unloading (HU) method is a widely accepted National Aeronautics and Space Administration (NASA) ground-based model for studying disuse-atrophy in rodents. Our study evaluated an alternant method to the gold-standard Morey-Holton HU tail-traction technique in mice. Fifty-four female mice (4-8 mo.) were HU for 14 days (n=34) or 28 days (n=20). Recovery from HU was assessed after 3 days of normal cage ambulation following HU (n=22). Aged matched mice (n=76) served as weight-bearing controls. Prior to HU a tail ring was formed with a 2-0 sterile surgical steel wire that was passed through the 5(th), 6(th), or 7(th) inter-vertebral disc space and shaped into a ring from which the mice were suspended. Vertebral location for the tail-ring was selected to appropriately balance animal body weight without interfering with defecation. We determined the success of this novel HU technique by assessing body weight before and after HU, degree of soleus atrophy, and adrenal mass following HU. Body weight of the mice prior to HU (24.3 ± 2.9g) did not significantly decline immediately after 14d of HU (22.7 ± 1.9g), 28d of HU (21.3 + 2.1g) or after 3 days recovery (24.0 ± 1.8g). Soleus muscle mass significantly declined (-39.1%, and -46.6%) following HU for 14 days and 28 days respectively (p<0.001). Following 3 days of recovery soleus mass significantly increased to 74% of control values. Adrenal weights of HU mice were not different compared to control mice. The success of our novel HU method is evidenced by the maintenance of animal body weight, comparable adrenal gland weights, and soleus atrophy following HU, corresponding to expected literature values. The primary advantages of this HU method include: 1) ease of tail examination during suspension; 2) decreased likelihood of cyanotic, inflamed, and/or necrotic tails frequently observed with tail-taping and HU; 3) no possibility of mice chewing the traction tape and coming out of the suspension

dNTP deficiency induced by HU via inhibiting ribonucleotide reductase affects neural tube development

International Nuclear Information System (INIS)

Guan, Zhen; Wang, Xiuwei; Dong, Yanting; Xu, Lin; Zhu, Zhiqiang; Wang, Jianhua; Zhang, Ting; Niu, Bo

2015-01-01

Highlights: • Murine NTDs were successfully induced by means of hydroxyurea (HU). • The impairment of dNTP was induced via inhibition of ribonucleotide reductase. • dNTP deficiency induced by HU caused defective DNA synthesis and repair. • Abnormal apoptosis and proliferation induced by HU affected neural tube development. - Abstract: Exposure to environmental toxic chemicals in utero during the neural tube development period can cause developmental disorders. To evaluate the disruption of neural tube development programming, the murine neural tube defects (NTDs) model was induced by interrupting folate metabolism using methotrexate in our previous study. The present study aimed to examine the effects of dNTP deficiency induced by hydroxyurea (HU), a specific ribonucleotide reductase (RNR) inhibitor, during murine neural tube development. Pregnant C57BL/6J mice were intraperitoneally injected with various doses of HU on gestation day (GD) 7.5, and the embryos were checked on GD 11.5. RNR activity and deoxynucleoside triphosphate (dNTP) levels were measured in the optimal dose. Additionally, DNA damage was examined by comet analysis and terminal deoxynucleotidyl transferase mediated dUTP nick end-labeling (TUNEL) assay. Cellular behaviors in NTDs embryos were evaluated with phosphorylation of histone H3 (PH-3) and caspase-3 using immunohistochemistry and western blot analysis. The results showed that NTDs were observed mostly with HU treatment at an optimal dose of 225 mg/kg b/w. RNR activity was inhibited and dNTP levels were decreased in HU-treated embryos with NTDs. Additionally, increased DNA damage, decreased proliferation, and increased caspase-3 were significant in NTDs embryos compared to the controls. Results indicated that HU induced murine NTDs model by disturbing dNTP metabolism and further led to the abnormal cell balance between proliferation and apoptosis

Depletion of naive CD4 T cells by CXCR4-using HIV-1 variants occurs mainly through increased T-cell death and activation

NARCIS (Netherlands)

Hazenberg, Mette D.; Otto, Sigrid A.; Hamann, Dörte; Roos, Marijke Th L.; Schuitemaker, Hanneke; de Boer, Rob J.; Miedema, Frank

2003-01-01

Objective: Using SCID-Hu mice models and in vitro culture systems, it has been shown that syncytium inducing/CXCR4 using (X4) HIV-1 variants affect thymic function through infection and killing of CXCR4 thymocytes. The effect of X4-emergence on naive, memory and effector T-cell subset kinetics in

Effect of intermittent fasting with or without caloric restriction on prostate cancer growth and survival in SCID mice.

Science.gov (United States)

Buschemeyer, W Cooper; Klink, Joseph C; Mavropoulos, John C; Poulton, Susan H; Demark-Wahnefried, Wendy; Hursting, Stephen D; Cohen, Pinchas; Hwang, David; Johnson, Tracy L; Freedland, Stephen J

2010-07-01

Caloric restriction (CR) delays cancer growth in animals, though translation to humans is difficult. We hypothesized intermittent fasting (i.e., intermittent extreme CR), may be better tolerated and prolong survival of prostate cancer (CaP) bearing mice. We conducted a pilot study by injecting 105 male individually-housed SCID mice with LAPC-4 cells. When tumors reached 200 mm(3), 15 mice/group were randomized to one of seven diets and sacrificed when tumors reached 1,500 mm(3): Group 1: ad libitum 7 days/week; Group 2: fasted 1 day/week and ad libitum 6 days/week; Group 3: fasted 1 day/week and fed 6 days/week via paired feeding to maintain isocaloric conditions to Group 1; Group 4: 14% CR 7 days/week; Group 5: fasted 2 days/week and ad libitum 5 days/week; Group 6: fasted 2 day/week and fed 5 days/week via paired feeding to maintain isocaloric conditions to Group 1; Group 7: 28% CR 7 days/week. Sera from mice at sacrifice were analyzed for IGF-axis hormones. There were no significant differences in survival among any groups. However, relative to Group 1, there were non-significant trends for improved survival for Groups 3 (HR 0.65, P = 0.26), 5 (0.60, P = 0.18), 6 (HR 0.59, P = 0.16), and 7 (P = 0.59, P = 0.17). Relative to Group 1, body weights and IGF-1 levels were significantly lower in Groups 6 and 7. This exploratory study found non-significant trends toward improved survival with some intermittent fasting regimens, in the absence of weight loss. Larger appropriately powered studies to detect modest, but clinically important differences are necessary to confirm these findings.

Improved function and proliferation of adult human beta cells engrafted in diabetic immunodeficient NOD-scid IL2rγnull mice treated with alogliptin

Directory of Open Access Journals (Sweden)

Jurczyk A

2013-12-01

Full Text Available Agata Jurczyk,1 Philip diIorio,1 Dean Brostowin,1 Linda Leehy,1 Chaoxing Yang,1 Fumihiko Urano,2 David M Harlan,3 Leonard D Shultz,4 Dale L Greiner,1 Rita Bortell1 1Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 2Department of Medicine, Washington University School of Medicine, St Louis, MO, 3Department of Medicine, University of Massachusetts Medical School, Worcester, MA, 4The Jackson Laboratory, Bar Harbor, ME, USA Purpose: Dipeptidyl-peptidase-4 (DPP-4 inhibitors are known to increase insulin secretion and beta cell proliferation in rodents. To investigate the effects on human beta cells in vivo, we utilize immunodeficient mice transplanted with human islets. The study goal was to determine the efficacy of alogliptin, a DPP-4 inhibitor, to enhance human beta cell function and proliferation in an in vivo context using diabetic immunodeficient mice engrafted with human pancreatic islets. Methods: Streptozotocin-induced diabetic NOD-scid IL2rγnull (NSG mice were transplanted with adult human islets in three separate trials. Transplanted mice were treated daily by gavage with alogliptin (30 mg/kg/day or vehicle control. Islet graft function was compared using glucose tolerance tests and non-fasting plasma levels of human insulin and C-peptide; beta cell proliferation was determined by bromodeoxyuridine (BrdU incorporation. Results: Glucose tolerance tests were significantly improved by alogliptin treatment for mice transplanted with islets from two of the three human islet donors. Islet-engrafted mice treated with alogliptin also had significantly higher plasma levels of human insulin and C-peptide compared to vehicle controls. The percentage of insulin+BrdU+ cells in human islet grafts from alogliptin-treated mice was approximately 10-fold more than from vehicle control mice, consistent with a significant increase in human beta cell proliferation. Conclusion: Human islet-engrafted immunodeficient mice

Foster Creative Engineers by PBL

DEFF Research Database (Denmark)

Zhou, Chunfang; Nielsen, Jens Frederik Dalsgaard; Kolmos, Anette

2011-01-01

In recent years, Problem and Project Based Learning (PBL) has been employed by a growing number of educational institutions to foster creative engineers. This paper aims to explore how PBL can develop creativity in engineering education. Accordingly, a qualitative case study was carried out...... with a student satellite project (AAUSAT3) in the department of electronic systems at Aalborg University in Denmark. Multiple methods including interviews and observation were employed. The analysis of the empirical data leads to the findings and discussions that PBL can foster creative engineers by providing...... conditions of problem analysis and solving, the shift from teaching to learning and team based projects. This research therefore contributes to both theory and practice in the PBL setting of engineering education....

R5 strains of human immunodeficiency virus type 1 from rapid progressors lacking X4 strains do not possess X4-type pathogenicity in human thymus

NARCIS (Netherlands)

Berkowitz, R. D.; van't Wout, A. B.; Kootstra, N. A.; Moreno, M. E.; Linquist-Stepps, V. D.; Bare, C.; Stoddart, C. A.; Schuitemaker, H.; McCune, J. M.

1999-01-01

Some individuals infected with only R5 strains of human immunodeficiency virus type 1 progress to AIDS as quickly as individuals harboring X4 strains. We determined that three R5 viruses were much less pathogenic than an X4 virus in SCID-hu Thy/Liv mice, suggesting that R5 virus-mediated rapid

Human bone marrow mesenchymal stem cells display anti-cancer activity in SCID mice bearing disseminated non-Hodgkin's lymphoma xenografts.

Directory of Open Access Journals (Sweden)

Paola Secchiero

Full Text Available BACKGROUND: Although multimodality treatment can induce high rate of remission in many subtypes of non-Hodgkin's lymphoma (NHL, significant proportions of patients relapse with incurable disease. The effect of human bone marrow (BM mesenchymal stem cells (MSC on tumor cell growth is controversial, and no specific information is available on the effect of BM-MSC on NHL. METHODOLOGY/PRINCIPAL FINDINGS: The effect of BM-MSC was analyzed in two in vivo models of disseminated non-Hodgkin's lymphomas with an indolent (EBV(- Burkitt-type BJAB, median survival = 46 days and an aggressive (EBV(+ B lymphoblastoid SKW6.4, median survival = 27 days behavior in nude-SCID mice. Intra-peritoneal (i.p. injection of MSC (4 days after i.p. injection of lymphoma cells significantly increased the overall survival at an optimal MSC:lymphoma ratio of 1:10 in both xenograft models (BJAB+MSC, median survival = 58.5 days; SKW6.4+MSC, median survival = 40 days. Upon MSC injection, i.p. tumor masses developed more slowly and, at the histopathological observation, exhibited a massive stromal infiltration coupled to extensive intra-tumor necrosis. In in vitro experiments, we found that: i MSC/lymphoma co-cultures modestly affected lymphoma cell survival and were characterized by increased release of pro-angiogenic cytokines with respect to the MSC, or lymphoma, cultures; ii MSC induce the migration of endothelial cells in transwell assays, but promoted endothelial cell apoptosis in direct MSC/endothelial cell co-cultures. CONCLUSIONS/SIGNIFICANCE: Our data demonstrate that BM-MSC exhibit anti-lymphoma activity in two distinct xenograft SCID mouse models of disseminated NHL.

PBL on Line: A Proposal for the Organization, Part-Time Monitoring and Assessment of PBL Group Activities

Science.gov (United States)

Marti, Enric; Gil, Debora; Gurguí, Antoni; Hernández-Sabaté, Aura; Rocarías, Jaume; Poveda, Ferran

2015-01-01

This report presents the organisation of PBL (Project Based Learning) for a subject included in the IT engineering degree course. It is the result of 10 years of experience of the implantation and continuous improvement of the PBL class structure. The latest innovations include the experience of part-time monitoring with PBL groups using the Open…

Alterations in the adenosine metabolism and CD39/CD73 adenosinergic machinery cause loss of Treg cell function and autoimmunity in ADA-deficient SCID

Science.gov (United States)

Sauer, Aisha V.; Brigida, Immacolata; Carriglio, Nicola; Jofra Hernandez, Raisa; Scaramuzza, Samantha; Clavenna, Daniela; Sanvito, Francesca; Poliani, Pietro L.; Gagliani, Nicola; Carlucci, Filippo; Tabucchi, Antonella; Roncarolo, Maria Grazia; Traggiai, Elisabetta; Villa, Anna

2012-01-01

Adenosine acts as anti-inflammatory mediator on the immune system and has been described in regulatory T cell (Treg)–mediated suppression. In the absence of adenosine deaminase (ADA), adenosine and other purine metabolites accumulate, leading to severe immunodeficiency with recurrent infections (ADA-SCID). Particularly ADA-deficient patients with late-onset forms and after enzyme replacement therapy (PEG-ADA) are known to manifest immune dysregulation. Herein we provide evidence that alterations in the purine metabolism interfere with Treg function, thereby contributing to autoimmune manifestations in ADA deficiency. Tregs isolated from PEG-ADA–treated patients are reduced in number and show decreased suppressive activity, whereas they are corrected after gene therapy. Untreated murine ADA−/− Tregs show alterations in the plasma membrane CD39/CD73 ectonucleotidase machinery and limited suppressive activity via extracellular adenosine. PEG-ADA–treated mice developed multiple autoantibodies and hypothyroidism in contrast to mice treated with bone marrow transplantation or gene therapy. Tregs isolated from PEG-ADA–treated mice lacked suppressive activity, suggesting that this treatment interferes with Treg functionality. The alterations in the CD39/CD73 adenosinergic machinery and loss of function in ADA-deficient Tregs provide new insights into a predisposition to autoimmunity and the underlying mechanisms causing defective peripheral tolerance in ADA-SCID. Trials were registered at www.clinicaltrials.gov as NCT00598481/NCT00599781. PMID:22184407

If PBL is the answer, then what is the problem?

DEFF Research Database (Denmark)

Huttel, Hans; Gnaur, Dorina

2017-01-01

of project work in the undergraduate degree programme in computer science at Aalborg University. Danish PBL-based higher education institutions espouse the qualities of problembased projects but actual practice shows a different picture. The predominant use of project catalogues and the formal requirements...... ways of structuring problem-based project work in different settings. We identify the need for a further discussion of the conflict between the espoused ideals of PBL and the actual practice at PBL-based higher education. In particular, much greater attention should be devoted to the practice...... of semester coordination. This paper gives a critical analysis of the practice in PBL-based higher education and should be of value to practitioners and decision makers in these settings....

Comparison of PBL Curricua within Control Engineering Education

DEFF Research Database (Denmark)

Fernandez-Samaca, Liliana; Nielsen, Kirsten M.; Ramirez, Jose Miguel

2011-01-01

During the last twenty years, various forms of PBL have been implemented in diverse educational programs and national policy regulations, and to different extents, ranging from a single course level to an integrated PBL curriculum. This has resulted in a variety of PBL curriculum practices....... In this article, a comparison of two PBL cases will be described in order to study the advantages and disadvantages of the two systems. One case presents a single level comprised of two courses and the other one is an integrated PBL curriculum, and both are focused on control engineering courses. The PBL...

Evaluating the impact of a PBL-course for first-year engineering students learning through PBL-projects

DEFF Research Database (Denmark)

Mosgaard, Mette; Spliid, Claus Monrad

2011-01-01

The PBL-course for engineering students at Aalborg University provides support for student-groups' project-work and collaborative learning when planning and conducting scientific problem-based project with societal relevance. The results of a survey among some of the groups indicate that the limi...... that the limited experience with the Aalborg PBL Model clearly affects groups' perception of importance of using different PBL-tools. Development of process-competencies depends upon facilitation of reflection and experimentation....

A comparison of course-related stressors in undergraduate problem-based learning (PBL versus non-PBL medical programmes

Directory of Open Access Journals (Sweden)

Ross Elizabeth E

2009-09-01

Full Text Available Abstract Background Medical students report high levels of stress related to their medical training as well as to other personal and financial factors. The aim of this study is to investigate whether there are differences in course-related stressors reported by medical students on undergraduate problem-based learning (PBL and non-PBL programmes in the UK. Method A cross-sectional study of second-year medical students in two UK medical schools (one PBL and one non-PBL programme was conducted. A 16-question self-report questionnaire, derived from the Perceived Medical Student Stress Scale and the Higher Education Stress Inventory, was used to measure course-related stressors. Following univariate analysis of each stressor between groups, multivariate logistic regression was used to determine which stressors were the best predictors of each course type, while controlling for socio-demographic differences between the groups. Results A total of 280 students responded. Compared to the non-PBL students (N = 197, the PBL students (N = 83 were significantly more likely to agree that: they did not know what the faculty expected of them (Odds Ratio (OR = 0.38, p = 0.03; there were too many small group sessions facilitated only by students resulting in an unclear curriculum (OR = 0.04, p Conclusion There are significant differences in the perceived course-related stressors affecting medical students on PBL and non-PBL programmes. Course designers and student support services should therefore tailor their work to minimise, or help students cope with, the specific stressors on each course type to ensure optimum learning and wellbeing among our future doctors.

APPLYING PBL AND ZUVIO TO ENHANCE ENGLISH LEARNING MOTIVATION

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BOR-TYNG WANG

2016-06-01

Full Text Available To inspire college students’ English learning motivation, this study proposed to combine Project-Based Learning (PBL with ZUVIO online teaching platform. The traditional teaching methods focus on teachers’ direct instruction in class, which mean that students only receive knowledge from teachers instead of formulating the answers on their own. This also decreases interaction in the classroom and prevents students from collaborating with other peers. However, implementing PBL and ZUVIO would allow students to apply knowledge in the social context and work with their classmates. In this study, two freshman English classes in a private university in central Taiwan were chosen as the sample. The students in both classes were low-level students (CEF A2 level. One class (N = 39 was chosen as the experimental group which had to complete the PBL tasks assigned by the teacher and use peer assessment function in ZUVIO for one academic year. The other class (N = 43 was chosen as the control group which was given the traditional teaching instructions. The results showed that the experimental group performed better on the midterm exam compared to the control group during both semesters (p = 0.001. Additionally, the results of the questionnaire showed that students’ motivation to learn English increased when using PBL and ZUVIO as teaching methods. To cite this document: Bor-Tyng Wang, "Applying PBL and ZUVIO to enhance English learning motivation", International Journal of Cyber Society and Education, Vol. 9, No. 1, pp. 1-16, 2016.

A comparison of course-related stressors in undergraduate problem-based learning (PBL) versus non-PBL medical programmes.

Science.gov (United States)

Lewis, Alexander D; Menezes, Darryl A Braganza; McDermott, Helen E; Hibbert, Louise J; Brennan, Sarah-Louise; Ross, Elizabeth E; Jones, Lisa A

2009-09-13

Medical students report high levels of stress related to their medical training as well as to other personal and financial factors. The aim of this study is to investigate whether there are differences in course-related stressors reported by medical students on undergraduate problem-based learning (PBL) and non-PBL programmes in the UK. A cross-sectional study of second-year medical students in two UK medical schools (one PBL and one non-PBL programme) was conducted. A 16-question self-report questionnaire, derived from the Perceived Medical Student Stress Scale and the Higher Education Stress Inventory, was used to measure course-related stressors. Following univariate analysis of each stressor between groups, multivariate logistic regression was used to determine which stressors were the best predictors of each course type, while controlling for socio-demographic differences between the groups. A total of 280 students responded. Compared to the non-PBL students (N = 197), the PBL students (N = 83) were significantly more likely to agree that: they did not know what the faculty expected of them (Odds Ratio (OR) = 0.38, p = 0.03); there were too many small group sessions facilitated only by students resulting in an unclear curriculum (OR = 0.04, p academic subjects of interest (OR = 0.40, p = 0.02). They were significantly more likely to disagree that: there was a lack of encouragement from teachers (OR = 3.11, p = 0.02); and that the medical course fostered a sense of anonymity and feelings of isolation amongst students (OR = 3.42, p = 0.008). There are significant differences in the perceived course-related stressors affecting medical students on PBL and non-PBL programmes. Course designers and student support services should therefore tailor their work to minimise, or help students cope with, the specific stressors on each course type to ensure optimum learning and wellbeing among our future doctors.

Identifying needs to develop a PBL staff development program

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Prarthana Coffin

2013-08-01

Full Text Available Staff development is a crucial element for educational intervention. Recognizing the importance of staff development, this study aims to pin-point suitable methodologies in developing a Problem-Based Learning (PBL academic staff development program for a higher education institute where PBL has become an intervention alternative. The study aims to answer the following research questions 1 how can university academic staff be assisted to acquire pedagogical competences for an initiative of the implementation of PBL curriculum? 2 What kinds of support do university academic staff need in order to maintain PBL implementation? Through a combination of a literature review, interviews with 6 PBL experts which emphasize the importance of PBL facilitators, and document analysis of reflection notes from 18 trainees of a PBL workshop, this study will produce a guideline in developing a PBL Academic Staff Development Program for an institute wishes to implement and retain PBL as the education strategy.

The PBL projects: where we've been and where we are going

Science.gov (United States)

Donnelly, Judith F.; Massa, Nicholas M.

2015-10-01

Problem-based learning (PBL) is an instructional approach in which students learn course content by using a structured approach to collaboratively solving complex real-world problems. PBL addresses widespread industry concern that graduates of technician and engineering programs often have difficulty applying their technical knowledge to novel situations and working effectively in teams. Over the past 9 years, the PBL Projects of the New England Board of Higher Education (Boston, MA) have developed instructional strategies and materials that research shows address industry concerns by improving student learning, retention, critical thinking and problem-solving skills as well as the transfer of knowledge to new situations. In this paper we present a retrospective of the PBL Projects, three National Science Foundation Advanced Technology Education (NSF-ATE) projects that developed twenty interdisciplinary multi-media PBL case studies called "Challenges" in the topic areas of optics/photonics, sustainable technology and advanced manufacturing, provided faculty professional development in the use of PBL in the classroom to teachers across the U.S. and abroad, and conducted research on the efficacy of the PBL method. We will describe the resources built into the Challenges to scaffold the development of students' problem solving and critical thinking skills and the support provided to instructors who wish to create a student-centered classroom by incorporating PBL. Finally, we will discuss plans for next steps and examine strategies for taking PBL to the next level through actual industry-based problem solving experiences.

Promoting and supporting PBL interests world wide

DEFF Research Database (Denmark)

Enemark, Stig; Kolmos, Anette; Moesby, Egon

2006-01-01

of projects world wide focusing on institutional change toward a more student centred, project organised, and problem based approach to learning. The Centre is also establishing a UCPBL Global Network on Problem Based Learning in order to facilitate better access to and co-operation within the PBL area.......-Based Learning (PBL) in Engineering Education, an increasing number of universities and engineering schools throughout the world are seeking consultancy and cooperation with Aalborg University. The establishment of UCPBL is therefore a timely opportunity to merge the efforts into one organisational structure...... aiming to promote and support PBL interests worldwide. This paper presents the UCPBL profile and plan of action. This includes a wide range of activities such as promoting research and development within the various PBL models and their implementation; Education and training in PBL through offering...

A repeated injection of polyethyleneglycol-conjugated recombinant human butyrylcholinesterase elicits immune response in mice

International Nuclear Information System (INIS)

Chilukuri, Nageswararao; Sun Wei; Parikh, Kalpana; Naik, Ramachandra S.; Tang Lin; Doctor, Bhupendra P.; Saxena, Ashima

2008-01-01

Human serum butyrylcholinesterase (Hu BChE) serves as an efficacious bioscavenger of highly toxic organophosphorus (OP) compounds. Since there is a concern that the supply of native Hu BChE may be limited, monomeric and tetrameric forms of recombinant Hu BChE (rHu BChE) were evaluated as replacements and found that they lacked sufficient stability in vivo. However, their in vivo stability could be significantly prolonged by conjugation with polyethyleneglycol-20K (PEG) suggesting that monomeric and tetrameric PEG-rHu BChE could function as bioscavengers. Here, the immunogenicity of PEG-rHu BChE was evaluated in mice following two injections given four weeks apart. In addition to pharmacokinetic parameters, such as mean residence time, maximal concentration, time to reach the maximal concentration, elimination half-life and area under the plasma concentration-time curve extrapolated to infinity, the presence of circulating anti-rHu BChE antibodies was also determined. Although the pharmacokinetic parameters were significantly improved for the first injection of monomeric and tetrameric PEG-rHu BChEs, they were much lower for the second injection. Anti-rHu BChE antibodies were detected in the blood of mice following the first and second enzyme injections and their levels were approximately higher by 5-fold and 2-fold in mice injected with monomeric and tetrameric PEG-rHu BChEs as compared to mice injected with unconjugated enzymes. The findings that the rapid clearance of a repeat injection of PEG-rHu BChEs in mice which coincides with the presence of circulating anti-rHu BChE antibodies suggest that PEG conjugation prolonged the circulatory stability of rHu BChE but failed to eliminate its immunogenicity in mice

MicroPET/CT imaging of patient-derived pancreatic cancer xenografts implanted subcutaneously or orthotopically in NOD-scid mice using 64Cu-NOTA-panitumumab F(ab')2 fragments

International Nuclear Information System (INIS)

Boyle, Amanda J.; Cao, Ping-Jiang; Hedley, David W.; Sidhu, Sachdev S.; Winnik, Mitchell A.; Reilly, Raymond M.

2015-01-01

Introduction: Our objective was to study microPET/CT imaging of patient-derived pancreatic cancer xenografts in NOD-scid mice using F(ab') 2 fragments of the fully-human anti-EGFR monoclonal antibody, panitumumab (Vectibix) labeled with 64 Cu. More than 90% of pancreatic cancers are EGFR-positive. Methods: F(ab') 2 fragments were produced by proteolytic digestion of panitumumab IgG or non-specific human IgG, purified by ultrafiltration then modified with NOTA chelators for complexing 64 Cu. Panitumumab IgG and Fab fragments were similarly labeled with 64 Cu. EGFR immunoreactivity was determined in competition and direct (saturation) cell binding assays. The biodistribution of 64 Cu-labeled panitumumab IgG, F(ab') 2 and Fab was compared in non-tumor-bearing Balb/c mice. MicroPET/CT and biodistribution studies were performed in NOD-scid mice engrafted subcutaneously (s.c.) or orthotopically with patient-derived OCIP23 pancreatic tumors, or in NOD-scid with s.c. PANC-1 human pancreatic cancer xenografts. Results: Panitumumab F(ab') 2 fragments were produced in high purity (> 90%), derivitized with 3.2 ± 0.7 NOTA/F(ab') 2 , and labeled with 64 Cu (0.3–3.6 MBq/μg). The binding of 64 Cu-NOTA-panitumumab F(ab') 2 to OCIP23 or PANC-1 cells was decreased significantly by an excess of panitumumab IgG. The K d for binding of 64 Cu-NOTA-panitumumab F(ab') 2 to EGFR on PANC-1 cells was 0.14 ± 0.05 nmol/L. F(ab') 2 fragments exhibited more suitable normal tissue distribution for tumor imaging with 64 Cu than panitumumab IgG or Fab. Tumor uptake at 48 h post injection (p.i.) of 64 Cu-NOTA-panitumumab F(ab') 2 was 12.0 ± 0.9% injected dose/g (ID/g) in s.c. and 11.8 ± 0.9% ID/g in orthotopic OCIP23 tumors vs. 6.1 ± 1.1% ID/g in s.c. PANC-1 xenografts. Tumor/Blood (T/B) ratios were 5:1 to 9:1 for OCIP23 and 2.4:1 for PANC-1 tumors. Tumor uptake of 64 Cu-NOTA-non-specific F(ab') 2 in OCIP23 xenografts was 5-fold lower than 64

PROBLEM-BASED LEARNING (PBL) LANGUAGE CASE-CRAFTING MODEL (PBL-LcCRAFT): LANGUAGE-IN-USE AND THE 3R

OpenAIRE

Mohd-Ali, Suraini; Baharun, Hazleena; Harun, Haliza; Darmi, Ramiaida; Mat Saad, Noor Saazai; Puteh-Behak, Fariza; Massari, Norhaili; Ahmad Mahir, Normazla

2017-01-01

This article describes a new PBL case designmodel for language practitioners that emerged from an action research projecton PBL case-design training for language practitioners. Participants of theaction research project underwent two cycles of PBL case-design training. Datacollection tools consisting of an observation checklist and a series of focusgroup interview were used to collect data from the participants. Data gatheredwere then analyzed using content analysis for emerging themes. Findi...

Overexpression of IGF-I in skeletal muscle of transgenic mice does not prevent unloading-induced atrophy

Science.gov (United States)

Criswell, D. S.; Booth, F. W.; DeMayo, F.; Schwartz, R. J.; Gordon, S. E.; Fiorotto, M. L.

1998-01-01

This study examined the association between local insulin-like growth factor I (IGF-I) overexpression and atrophy in skeletal muscle. We hypothesized that endogenous skeletal muscle IGF-I mRNA expression would decrease with hindlimb unloading (HU) in mice, and that transgenic mice overexpressing human IGF-I (hIGF-I) specifically in skeletal muscle would exhibit less atrophy after HU. Male transgenic mice and nontransgenic mice from the parent strain (FVB) were divided into four groups (n = 10/group): 1) transgenic, weight-bearing (IGF-I/WB); 2) transgenic, hindlimb unloaded (IGF-I/HU); 3) nontransgenic, weight-bearing (FVB/WB); and 4) nontransgenic, hindlimb unloaded (FVB/HU). HU groups were hindlimb unloaded for 14 days. Body mass was reduced (P < 0.05) after HU in both IGF-I (-9%) and FVB mice (-13%). Contrary to our hypothesis, we found that the relative abundance of mRNA for the endogenous rodent IGF-I (rIGF-I) was unaltered by HU in the gastrocnemius (GAST) muscle of wild-type FVB mice. High-level expression of hIGF-I peptide and mRNA was confirmed in the GAST and tibialis anterior (TA) muscles of the transgenic mice. Nevertheless, masses of the GAST and TA muscles were reduced (P < 0.05) in both FVB/HU and IGF-I/HU groups compared with FVB/WB and IGF-I/WB groups, respectively, and the percent atrophy in mass of these muscles did not differ between FVB and IGF-I mice. Therefore, skeletal muscle atrophy may not be associated with a reduction of endogenous rIGF-I mRNA level in 14-day HU mice. We conclude that high local expression of hIGF-I mRNA and peptide in skeletal muscle alone cannot attenuate unloading-induced atrophy of fast-twitch muscle in mice.

Hydroxyurea treatment inhibits proliferation of Cryptococcus neoformans in mice

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Kaushlendra eTripathi

2012-05-01

Full Text Available The fungal pathogen Cryptococcus neoformans (Cn is a serious threat to immunocompromised individuals, especially for HIV patients who develop meningoencephalitis. For effective cryptococcal treatment, novel antifungal drugs or innovative combination therapies are needed. Recently, sphingolipids have emerged as important bioactive molecules in the regulation of microbial pathogenesis. Previously we reported that the sphingolipid pathway gene, ISC1, which is responsible for ceramide production, is a major virulence factor in Cn infection. Here we report our studies of the role of ISC1 during genotoxic stress induced by the antineoplastic hydroxyurea (HU and methylmethane sulfonate (MMS, which affect DNA replication and genome integrity. We observed that Cn cells lacking ISC1 are highly sensitive to HU and MMS in a rich culture medium. HU affected cell division of Cn cells lacking the ISC1 gene, resulting in cell clusters. Cn ISC1, when expressed in a Saccharomyces cerevisiae (Sc strain lacking its own ISC1 gene, restored HU resistance. In macrophage-like cells, although HU affected the proliferation of WT Cn cells by 50% at the concentration tested, HU completely inhibited Cn isc1-delta cell proliferation. Interestingly, our preliminary data show that mice infected with WT or Cn isc1-delta cells and subsequently treated with HU had longer lifespans than untreated, infected control mice. Our work suggests that the sphingolipid pathway gene, ISC1, is a likely target for combination therapy with traditional drugs such as HU.

Globalization of Problem-based Learning (PBL: Cross-cultural Implications

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Matthew Choon-Eng Gwee

2008-03-01

Full Text Available Problem-based learning (PBL is essentially a learning system design that incorporates several educational strategies to optimize student-centered learning outcomes beyond just knowledge acquisition. PBL was implemented almost four decades ago as an innovative and alternative pathway to learning in medical education in McMaster University Medical School. Since then, PBL has spread widely across the world and has now been adopted globally, including in much of Asia. The globalization of PBL has important cross-cultural implications. Delivery of instruction in PBL involves active peer teaching-learning in an open communication style. Consequently, this may pose an apparent serious conflict with the Asian communication style generally dominated by a cultural reticence. However, evidence available, especially from the PBL experience of some senior Korean medical students doing an elective in the University of Toronto Medical School and the cross-cultural PBL experience initiated by Kaohsiung Medical University, strongly suggests creating a conducive and supportive learning environment for students learning in a PBL setting can overcome the perceived cultural barriers; that is, nurture matters more than culture in the learning environment. Karaoke is very much an Asian initiative. The Karaoke culture and philosophy provide a useful lesson on how to create a conducive and supportive environment to encourage, enhance and motivate group activity. Some key attributes associated with Asian culture are in fact consistent with, and aligned to, some of the basic tenets of PBL, including the congruence between the Asian emphasis on group before individual interest, and the collaborative small group learning design used in PBL. Although there are great expectations of the educational outcomes students can acquire from PBL, the available evidence supports the contention the actual educational outcomes acquired from PBL do not really match the expected

Globalization of problem-based learning (PBL): cross-cultural implications.

Science.gov (United States)

Gwee, Matthew Choon-Eng

2008-03-01

Problem-based learning (PBL) is essentially a learning system design that incorporates several educational strategies to optimize student-centered learning outcomes beyond just knowledge acquisition. PBL was implemented almost four decades ago as an innovative and alternative pathway to learning in medical education in McMaster University Medical School. Since then, PBL has spread widely across the world and has now been adopted globally, including in much of Asia. The globalization of PBL has important cross-cultural implications. Delivery of instruction in PBL involves active peer teaching-learning in an open communication style. Consequently, this may pose an apparent serious conflict with the Asian communication style generally dominated by a cultural reticence. However, evidence available, especially from the PBL experience of some senior Korean medical students doing an elective in the University of Toronto Medical School and the cross-cultural PBL experience initiated by Kaohsiung Medical University, strongly suggests creating a conducive and supportive learning environment for students learning in a PBL setting can overcome the perceived cultural barriers; that is, nurture matters more than culture in the learning environment. Karaoke is very much an Asian initiative. The Karaoke culture and philosophy provide a useful lesson on how to create a conducive and supportive environment to encourage, enhance and motivate group activity. Some key attributes associated with Asian culture are in fact consistent with, and aligned to, some of the basic tenets of PBL, including the congruence between the Asian emphasis on group before individual interest, and the collaborative small group learning design used in PBL. Although there are great expectations of the educational outcomes students can acquire from PBL, the available evidence supports the contention the actual educational outcomes acquired from PBL do not really match the expected educational outcomes commonly

PBL online

DEFF Research Database (Denmark)

Kolbæk, Ditte; Nortvig, Anne-Mette

2017-01-01

Problem- and Project-Based Learning (PBL) is a widely used pedagogical method in higher education. Although PBL encourages self-directed learning and works with the students’ own projects and problems, it also includes teacher presentations, discussions and group reflections, both on......-campus and online. Therefore, the teacher’s plans might be relevant to the students’ projects, but that is not always the case. This study investigates how master’s students interact with an online Problem-Based Learning design and examines how technology influences these interactions. The empirical data stem from...... lessons at an online master’s course, and they were collected and analyzed using a netnographic approach. The study finds that concepts like self-directed learning and active involvement of everyone can have very different meanings from the teachers’ and the students’ points of view. If the students do...

Performance Anxiety at English PBL Groups Among Taiwanese Medical Students: A Preliminary Study

Directory of Open Access Journals (Sweden)

Cheng-Sheng Chen

2008-03-01

Full Text Available Students' performance anxiety can impact negatively on the effectiveness of medical education reform, including performance in problem-based learning (PBL and in using English in discussion. This study aimed to investigate the nature of performance anxiety among Taiwanese medical students in an English-language PBL group. Eighteen Taiwanese, one American and four Asian medical students who were attending an international PBL workshop were enrolled. A questionnaire seeking demographic data and experience in use of PBL and eight questions evaluating performance anxiety were administered. The performance anxiety of Taiwanese medical students was compared to that of the Asians and the one American. Frequencies of each performance anxiety were calculated. The results suggested that the Taiwanese students showed more anxiety than the one student from the United States, but less than other Asian students. The acts of giving a report, being the center of attention, and talking in the PBL group were the most common situations related to anxiety in PBL groups. Using English and working in a new PBL environment are possible sources of anxiety. The presence of anxiety among the Taiwanese medical students in English PBL groups implies the necessity for developing an effective strategy to deal with students' performance anxiety.

Development of a model for marburgvirus based on severe-combined immunodeficiency mice

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Kalina Warren V

2007-10-01

Full Text Available Abstract The filoviruses, Ebola (EBOV and Marburg (MARV, cause a lethal hemorrhagic fever. Human isolates of MARV are not lethal to immmunocompetent adult mice and, to date, there are no reports of a mouse-adapted MARV model. Previously, a uniformly lethal EBOV-Zaire mouse-adapted virus was developed by performing 9 sequential passages in progressively older mice (suckling to adult. Evaluation of this model identified many similarities between infection in mice and nonhuman primates, including viral tropism for antigen-presenting cells, high viral titers in the spleen and liver, and an equivalent mean time to death. Existence of the EBOV mouse model has increased our understanding of host responses to filovirus infections and likely has accelerated the development of countermeasures, as it is one of the only hemorrhagic fever viruses that has multiple candidate vaccines and therapeutics. Here, we demonstrate that serially passaging liver homogenates from MARV-infected severe combined immunodeficient (scid mice was highly successful in reducing the time to death in scid mice from 50–70 days to 7–10 days after MARV-Ci67, -Musoke, or -Ravn challenge. We performed serial sampling studies to characterize the pathology of these scid mouse-adapted MARV strains. These scid mouse-adapted MARV models appear to have many similar properties as the MARV models previously developed in guinea pigs and nonhuman primates. Also, as shown here, the scid-adapted MARV mouse models can be used to evaluate the efficacy of candidate antiviral therapeutic molecules, such as phosphorodiamidate morpholino oligomers or antibodies.

Development of Murine Cyp3a Knockout Chimeric Mice with Humanized Liver.

Science.gov (United States)

Kato, Kota; Ohbuchi, Masato; Hamamura, Satoko; Ohshita, Hiroki; Kazuki, Yasuhiro; Oshimura, Mitsuo; Sato, Koya; Nakada, Naoyuki; Kawamura, Akio; Usui, Takashi; Kamimura, Hidetaka; Tateno, Chise

2015-08-01

We developed murine CYP3A knockout ko chimeric mice with humanized liver expressing human P450S similar to those in humans and whose livers and small intestines do not express murine CYP3A this: approach may overcome effects of residual mouse metabolic enzymes like Cyp3a in conventional chimeric mice with humanized liver, such as PXB-mice [urokinase plasminogen activator/severe combined immunodeficiency (uPA/SCID) mice repopulated with over 70% human hepatocytes] to improve the prediction of drug metabolism and pharmacokinetics in humans. After human hepatocytes were transplanted into Cyp3a KO/uPA/SCID host mice, human albumin levels logarithmically increased until approximately 60 days after transplantation, findings similar to those in PXB-mice. Quantitative real-time-polymerase chain reaction analyses showed that hepatic human P450s, UGTs, SULTs, and transporters mRNA expression levels in Cyp3a KO chimeric mice were also similar to those in PXB-mice and confirmed the absence of Cyp3a11 mRNA expression in mouse liver and intestine. Findings for midazolam and triazolam metabolic activities in liver microsomes were comparable between Cyp3a KO chimeric mice and PXB-mice. In contrast, these activities in the intestine of Cyp3a KO chimeric mice were attenuated compared with PXB-mice. Owing to the knockout of murine Cyp3a, hepatic Cyp2b10 and 2c55 mRNA levels in Cyp3a KO/uPA/SCID mice (without hepatocyte transplants) were 8.4- and 61-fold upregulated compared with PXB-mice, respectively. However, human hepatocyte transplantation successfully restored Cyp2b10 level nearly fully and Cyp2c55 level partly (still 13-fold upregulated) compared with those in PXB-mice. Intestinal Cyp2b10 and 2c55 were also repressed by human hepatocyte transplantation in Cyp3a KO chimeric mice. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

Good supervision and PBL

DEFF Research Database (Denmark)

Otrel-Cass, Kathrin

This field study was conducted at the Faculty of Social Sciences at Aalborg University with the intention to investigate how students reflect on their experiences with supervision in a PBL environment. The overall aim of this study was to inform about the continued work in strengthening supervision...... at this faculty. This particular study invited Master level students to discuss: • How a typical supervision process proceeds • How they experienced and what they expected of PBL in the supervision process • What makes a good supervision process...

X irradiation combined with TNF alpha-related apoptosis-inducing ligand (TRAIL) reduces hypoxic regions of human gastric adenocarcinoma xenografts in SCID mice

International Nuclear Information System (INIS)

Takahashi, Momoko; Yasui, Hironobu; Ogura, Aki; Asanuma, Taketoshi; Inanami, Osamu; Kubota, Nobuo; Tsujitani, Michihiko; Kuwabara, Mikinori

2008-01-01

Our previous study showed that X irradiation induced the expression of death receptor DR5 on the cell surface in tumor cell lines under not only normoxia but also hypoxia. X irradiation combined with TNF α-related apoptosis-inducing ligand (TRAIL), which is the ligand of DR5, induced apoptosis in vitro (Takahashi et al., (2007) Journal of Radiation Research, 48: 461-468). In this report, we examined the in vivo antitumor efficacy of X irradiation combined with TRAIL treatment in tumor xenograft models derived from human gastric adenocarcinoma MKN45 and MKN28 cells in severe combined immunodeficiency (SCID) mice. X irradiation combined with TRAIL synergistically suppressed the tumor growth rates in the xenograft models derived from MKN45 and MKN28 cells, which have wild type Tp53 and mutated Tp53, respectively, indicating that the antitumor effects occurred in a Tp53-independent manner. Histological analysis showed that the combination of X irradiation and TRAIL induced caspase-3-dependent apoptotic cell death. Moreover, the immunohistochemical detection of hypoxic regions using the hypoxic marker pimonidazole revealed that caspase-3-dependent apoptosis occurred in the hypoxic regions in the tumors. These results indicated that X irradiation combined with TRAIL may be a useful treatment to reduce tumor growth in not only normoxic but also hypoxic regions. (author)

Glyoxalase 1 overexpression does not affect atherosclerotic lesion size and severity in ApoE-/- mice with or without diabetes

DEFF Research Database (Denmark)

Hanssen, Nordin M J; Brouwers, Olaf; Gijbels, Marion J

2014-01-01

are higher in rupture-prone plaques. We here investigated whether overexpression of human GLO1 in ApoE(-/-) mice could reduce the development of atherosclerosis. METHODS AND RESULTS: We crossed C57BL/6 ApoE(-/-) mice with C57BL/6 GLO1 overexpressing mice (huGLO1(+/-)) to generate ApoE(-/-) (n = 16) and Apo......E(-/-) huGLO1(+/-) (n = 20) mice. To induce diabetes, we injected a subset with streptozotocin (STZ) to generate diabetic ApoE(-/-) (n = 8) and ApoE(-/-) huGLO1(+/-) (n = 13) mice. All mice were fed chow and sacrificed at 25 weeks of age. The GLO1 activity was three-fold increased in huGLO1(+/-) aorta......, but aortic root lesion size and phenotype did not differ between mice with and without huGLO1(+/-) overexpression. We detected no differences in gene expression in aortic arches, in AGE levels and cytokines, in circulating cells, and endothelial function between ApoE(-/-) mice with and without huGLO1...

Constitutive activation of p38 MAPK in tumor cells contributes to osteolytic bone lesions in multiple myeloma

Science.gov (United States)

Yang, Jing; He, Jin; Wang, Ji; Cao, Yabing; Ling, Jianhua; Qian, Jianfei; Lu, Yong; Li, Haiyan; Zheng, Yuhuan; Lan, Yongsheng; Hong, Sungyoul; Matthews, Jairo; Starbuck, Michael W; Navone, Nora M; Orlowski, Robert Z.; Lin, Pei; Kwak, Larry W.; Yi, Qing

2012-01-01

Bone destruction is a hallmark of multiple myeloma and affects more than 80% of patients. However, current therapy is unable to completely cure and/or prevent bone lesions. Although it is accepted that myeloma cells mediate bone destruction by inhibition of osteoblasts and activation of osteoclasts, the underlying mechanism is still poorly understood. This study demonstrates that constitutive activation of p38 mitogen-activated protein kinase in myeloma cells is responsible for myeloma-induced osteolysis. Our results show that p38 is constitutively activated in most myeloma cell lines and primary myeloma cells from patients. Myeloma cells with high/detectable p38 activity, but not those with low/undetectable p38 activity, injected into SCID or SCID-hu mice caused bone destruction. Inhibition or knockdown of p38 in human myeloma reduced or prevented myeloma-induced osteolytic bone lesions without affecting tumor growth, survival, or homing to bone. Mechanistic studies showed that myeloma cell p38 activity inhibited osteoblastogenesis and bone formation and activated osteoclastogenesis and bone resorption in myeloma-bearing SCID mice. This study elucidates a novel molecular mechanism—sactivation of p38 signaling in myeloma cells—by which myeloma cells induce osteolytic bone lesions and indicates that targeting myeloma cell p38 may be a viable approach to treating or preventing myeloma bone disease. PMID:22425892

Balancing Teaching and Research in a PBL Context

DEFF Research Database (Denmark)

Turcan, Romeo V.

2016-01-01

as a main function area of a PBL model. However, the research component is not well embedded in a PBL model; most of the time teaching-based research is not considered or is not part of PBL teaching and learning. Hence, this paper studies the reciprocity of research-based teaching and teaching...

Maternal T-cell engraftment impedes with diagnosis of a SCID-ADA patient.

Science.gov (United States)

Lanfranchi, Arnalda; Lougaris, Vassilios; Notarangelo, Lucia Dora; Soncini, Elena; Comini, Marta; Beghin, Alessandra; Bolda, Federica; Montanelli, Alessandro; Imberti, Luisa; Porta, Fulvio

2018-02-02

We describe the case of a child affected by severe combined immunodeficiency (SCID) with adenosine deaminase (ADA) deficiency showing a maternal T-cell engraftment, a finding that has never been reported before. The presence of engrafted maternal T cells was misleading. Although ADA enzymatic levels were suggestive of ADA-SCID, the child did not present the classical signs of ADA deficiency; therefore, the initial diagnosis was of a conventional SCID. However, ADA toxic metabolites and molecular characterization confirmed this diagnosis. Polyethylene glycol-modified bovine (PEG) ADA therapy progressively decreased the number of maternal engrafted T cells. The child was grafted with full bone marrow from a matched unrelated donor, after a reduced conditioning regimen, and the result was the complete immunological reconstitution. Copyright © 2018 Elsevier Inc. All rights reserved.

PBL – Reflections after 10 years

DEFF Research Database (Denmark)

Soler, José

The poster describes course 34357 at DTU, where PBL has been used in the last 10 years. While the course responsibles where not aware initially that the used methodology was PBL, the poster describes the triggering idea for the initial taken choices, i.e. homogenize working methodologies...

PBL and critical thinking disposition in Chinese medical students

DEFF Research Database (Denmark)

Du, Xiangyun; Emmersen, Jeppe; Toft, Egon

2013-01-01

The purpose of this study was to explore the relationship of problem-based learning (PBL) and the development of critical thinking disposition (CT) and academic achievement in Chinese medical students using a cross-sectional randomized design. Medical students from China Medical University (CMU....... Total CT score was higher in PBL students (n=170) than non-PBL students (n=83) (304.7±36.8 vs. 279.2±39.4, p ...). There was no significant difference in terms of gender on the total CT score, though minor differences were seen in subscales favoring female PBL students. PBL students had higher CCS scores than non-PBL students, but not significantly (112.8±20.6 vs. 107.3±16.5; p=0.11). There was no significant correlation between CCS...

B lymphocytes not required for progression from insulitis to diabetes in non-obese diabetic mice.

Science.gov (United States)

Charlton, B; Zhang, M D; Slattery, R M

2001-12-01

Previous studies have implicated B lymphocytes in the pathogenesis of diabetes in the non-obese diabetic (NOD) mouse. While it is clear that B lymphocytes are necessary, it has not been clear at which stage of disease they play a role; early, late or both. To clarify when B lymphocytes are needed, T lymphocytes were transferred from 5-week-old NOD female mice to age-matched NOD/severe combined immunodeficiency (SCID) recipient mice. NOD/SCID mice, which lack functionally mature T and B lymphocytes, do not normally develop insulitis or insulin-dependent diabetes melitus (IDDM). The NOD/SCID mice that received purified T lymphocytes from 5-week-old NOD mice subsequently developed insulitis and diabetes even though they did not have detectable B lymphocytes. This suggests that while B lymphocytes may be essential for an initial priming event they are not requisite for disease progression in the NOD mouse.

Targeting Transfer in a STELLAR PBL Course for Pre-Service Teachers

OpenAIRE

Hmelo-Silver, Cindy E.; Derry, Sharon J.; Bitterman, Alan; Hatrak, Natalie

2009-01-01

Helping students in the professions apply conceptual ideas to the problems of practice is a key goal of problem-based learning (PBL). Because PBL is organized around small, collaborative groups, scaling up PBL to large, heterogeneous classes poses significant challenges for implementation. This study presents a hybrid model that mixes online and face-to-face PBL. The STELLAR system was developed to support online and hybrid PBL courses for pre-service teachers. It allows PBL to be implemented...

Temperature dependence of HU values for various water equivalent phantom materials

International Nuclear Information System (INIS)

Homolka, P.; Nowotny, R.; Gahleitner, A.

2002-01-01

The temperature dependence of water equivalent phantom materials used in radiotherapy and diagnostic imaging has been investigated. Samples of phantom materials based on epoxy resin, polyethylene, a polystyrene-polypropylene mixture and commercially available phantom materials (Solid Water TM , Gammex RMI and Plastic Water TM , Nuclear Associates) were scanned at temperatures from 15 to 40 deg. C and HU values determined. At a reference temperature of 20 deg. C materials optimized for CT applications give HU values close to zero while the commercial materials show an offset of 119.77 HU (Plastic Water) and 27.69 HU (Solid Water). Temperature dependence was lowest for epoxy-based materials (EPX-W: -0.23 HU deg. C -1 ; Solid Water: -0.25 HU deg. C -1 ) and highest for a polyethylene-based material (X0: -0.72 HU deg. C -1 ). A material based on a mixture of polystyrene and polypropylene (PSPP1: -0.27 HU deg. C -1 ) is comparable to epoxy-based materials and water (-0.29 HU deg. C -1 ). (author)

Insights into the mechanism of Piper betle leaf-induced contact leukomelanosis using C57BL/6 mice as the animal model and tyrosinase assays.

Science.gov (United States)

Liu, Han-Nan; Liu, Tsung-Yun; Chen, Chih-Chiang; Lee, Ding-Dar; Chang, Yun-Ting

2011-08-01

Steamed piper betle leaves (PBL) were once used by many Taiwanese women to treat pigment disorders on the face. Most women claimed a quick, favourable response at first, only to be overcome with facial leukomelanosis later. C57BL/6 mice were randomly assigned to different groups to study if PBL could cause the following effects: contact dermatitis, leukomelanosis, or hair bleaching. Intracellular melanin content was measured by tyrosinase assays. Most steamed PBL-treated mice developed contact dermatitis and postinflammatory hyperpigmentation (PIH) on their shaved backs. About half developed bleached hair to varying extents. The steamed PBL did not only bleach the hairs, but also, unexpectedly, stimulated melanocyte replication, indicated by the fact that the number of functional melanocytes in the tail epidermis increased significantly after treatment (P = 0.007). Using tyrosinase assays PBL extract at the undiluted concentration showed limited inhibition of melanogenesis, probably via melanocytotoxicity. The leukomelanosis observed in patients might be the consequence of PIH combined with a mixed reaction (hyper- and hypopigmentation), probably due to the different volatile chemicals that surface after steaming the PBL. This conflicting mixed reaction suggests that counteractive ingredients might exist in PBL. PBL, if purified, might be a promising source of a novel bleaching agent. © 2011 The Authors; Australasian Journal of Dermatology © 2011 The Australasian College of Dermatologists.

Severe combined immunodeficiency (SCID) presenting with neonatal aplastic anemia.

Science.gov (United States)

Scott, Angela; Glover, Jason; Skoda-Smith, Suzanne; Torgerson, Troy R; Xu, Min; Burroughs, Lauri M; Woolfrey, Ann E; Fleming, Mark D; Shimamura, Akiko

2015-11-01

Aplastic anemia in the neonate is rare. We report a case of severe combined immunodeficiency (SCID) presenting with neonatal aplastic anemia. This report highlights the importance of considering SCID early in the evaluation of neonatal aplastic anemia prior to the development of infectious complications. © 2015 Wiley Periodicals, Inc.

Comparison of monkeypox viruses pathogenesis in mice by in vivo imaging.

Directory of Open Access Journals (Sweden)

Jorge E Osorio

2009-08-01

Full Text Available Monkeypox viruses (MPXV cause human monkeypox, a zoonotic smallpox-like disease endemic to Africa, and are of worldwide public health and biodefense concern. Using viruses from the Congo (MPXV-2003-Congo-358 and West African (MPXV-2003-USA-044 clades, we constructed recombinant viruses that express the luciferase gene (MPXV-Congo/Luc+and MPXV-USA-Luc+ and compared their viral infection in mice by biophotonic imaging. BALB/c mice became infected by both MPXV clades, but they recovered and cleared the infection within 10 days post-infection (PI. However, infection in severe combined immune deficient (SCID BALB/c mice resulted in 100% lethality. Intraperitoneal (IP injection of both MPXV-Congo and MPXV-Congo/Luc+resulted in a systemic clinical disease and the same mean time-to-death at 9 (+/-0 days post-infection. Likewise, IP injection of SCID-BALB/c mice with MPXV-USA or the MPXV-USA-Luc+, resulted in similar disease but longer (P<0.05 mean time-to-death (11+/-0 days for both viruses compared to the Congo strains. Imaging studies in SCID mice showed luminescence in the abdomen within 24 hours PI with subsequent spread elsewhere. Animals infected with the MPXV-USA/Luc+had less intense luminescence in tissues than those inoculated with MPXV-Congo/Luc+, and systemic spread of the MPXV-USA/Luc+virus occurred approximately two days later than the MPXV-Congo/Luc+. The ovary was an important target for viral replication as evidenced by the high viral titers and immunohistochemistry. These studies demonstrate the suitability of a mouse model and biophotonic imaging to compare the disease progression and tissue tropism of MPX viruses.

Teacher's experiences in PBL: implications for practice

Science.gov (United States)

Alves, Anabela C.; Sousa, Rui M.; Fernandes, Sandra; Cardoso, Elisabete; Carvalho, Maria Alice; Figueiredo, Jorge; Pereira, Rui M. S.

2016-03-01

Project-Based Learning (PBL) has been implemented in the first year of the Industrial Engineering and Management programme at the University of Minho, Portugal, since 2004/2005. The purpose of this paper is to analyse and discuss teachers' experiences in PBL in this programme and to explore its implications for student learning and for teaching practices in higher education. For data collection, the research method used was written narratives to these teachers, at the end of the PBL semester. Findings suggest that teachers express a positive view of PBL as a learning approach. They identify student motivation and engagement, along with a better understanding of the application of concepts in real-life situations, as important outcomes of the project for students. Besides this, teachers also highlight the importance of the development of transversal skills by students throughout the project. Recommendations for future work and implications for practice will also be discussed.

Aryl hydrocarbon receptor-dependent retention of nuclear HuR suppresses cigarette smoke-induced cyclooxygenase-2 expression independent of DNA-binding.

Science.gov (United States)

Zago, Michela; Sheridan, Jared A; Nair, Parameswaran; Rico de Souza, Angela; Gallouzi, Imed-Eddine; Rousseau, Simon; Di Marco, Sergio; Hamid, Qutayba; Eidelman, David H; Baglole, Carolyn J

2013-01-01

The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor that responds to man-made environmental toxicants, has emerged as an endogenous regulator of cyclooxygenase-2 (Cox-2) by a mechanism that is poorly understood. In this study, we first used AhR-deficient (AhR(-/-) ) primary pulmonary cells, together with pharmacological tools to inhibit new RNA synthesis, to show that the AhR is a prominent factor in the destabilization of Cox-2 mRNA. The destabilization of Cox-2 mRNA and subsequent suppression of cigarette smoke-induced COX-2 protein expression by the AhR was independent of its ability to bind the dioxin response element (DRE), thereby differentiating the DRE-driven toxicological AhR pathway from its anti-inflammatory abilities. We further describe that the AhR destabilizes Cox-2 mRNA by sequestering HuR within the nucleus. The role of HuR in AhR stabilization of Cox-2 mRNA was confirmed by knockdown of HuR, which resulted in rapid Cox-2 mRNA degradation. Finally, in the lungs of AhR(-/-) mice exposed to cigarette smoke, there was little Cox-2 mRNA despite robust COX-2 protein expression, a finding that correlates with almost exclusive cytoplasmic HuR within the lungs of AhR(-/-) mice. Therefore, we propose that the AhR plays an important role in suppressing the expression of inflammatory proteins, a function that extends beyond the ability of the AhR to respond to man-made toxicants. These findings open the possibility that a DRE-independent AhR pathway may be exploited therapeutically as an anti-inflammatory target.

The inclusion of ADA-SCID in expanded newborn screening by tandem mass spectrometry.

Science.gov (United States)

la Marca, Giancarlo; Giocaliere, Elisa; Malvagia, Sabrina; Funghini, Silvia; Ombrone, Daniela; Della Bona, Maria Luisa; Canessa, Clementina; Lippi, Francesca; Romano, Francesca; Guerrini, Renzo; Resti, Massimo; Azzari, Chiara

2014-01-01

Severe combined immunodeficiency due to adenosine-deaminase defect (ADA-SCID) is usually deadly in childhood because of severe recurrent infections. When clinical diagnosis is done, permanent damages due to infections or metabolite accumulation are often present. Gene therapy, bone marrow transplantation or enzyme replacement therapy may be effective if started early. The aim of this study was to set-up a robust method suitable for screening with a minimized preparation process and with inexpensive running costs, for diagnosing ADA-SCID by tandem mass spectrometry. ADA-SCID satisfies all the criteria for inclusion in a newborn screening program. We describe a protocol revised to incorporate adenosine and 2-deoxyadenosine testing into an expanded newborn screening program. We assessed the effectiveness of this approach testing dried blood spots from 4 genetically confirmed early-onset and 5 delayed-onset ADA-SCID patients. Reference values were established on 50,000 healthy newborns (deoxyadenosine ADA) gene. The results show that the method having great simplicity, low cost and low process preparations can be fully applicable to a mass screening program. Copyright © 2013 Elsevier B.V. All rights reserved.

How We Manage Adenosine Deaminase-Deficient Severe Combined Immune Deficiency (ADA SCID).

Science.gov (United States)

Kohn, Donald B; Gaspar, H Bobby

2017-05-01

Adenosine deaminase-deficient severe combined immune deficiency (ADA SCID) accounts for 10-15% of cases of human SCID. From what was once a uniformly fatal disease, the prognosis for infants with ADA SCID has improved greatly based on the development of multiple therapeutic options, coupled with more frequent early diagnosis due to implementation of newborn screening for SCID. We review the various treatment approaches for ADA SCID including allogeneic hematopoietic stem cell transplantation (HSCT) from a human leukocyte antigen-matched sibling or family member or from a matched unrelated donor or a haplo-identical donor, autologous HSCT with gene correction of the hematopoietic stem cells (gene therapy-GT), and enzyme replacement therapy (ERT) with polyethylene glycol-conjugated adenosine deaminase. Based on growing evidence of safety and efficacy from GT, we propose a treatment algorithm for patients with ADA SCID that recommends HSCT from a matched family donor, when available, as a first choice, followed by GT as the next option, with allogeneic HSCT from an unrelated or haplo-identical donor or long-term ERT as other options.

Human adipose stromal cells expanded in human serum promote engraftment of human peripheral blood hematopoietic stem cells in NOD/SCID mice

International Nuclear Information System (INIS)

Kim, Su Jin; Cho, Hyun Hwa; Kim, Yeon Jeong; Seo, Su Yeong; Kim, Han Na; Lee, Jae Bong; Kim, Jae Ho; Chung, Joo Seop; Jung, Jin Sup

2005-01-01

Human mesenchymal stem cells (hMSC), that have been reported to be present in bone marrow, adipose tissues, dermis, muscles, and peripheral blood, have the potential to differentiate along different lineages including those forming bone, cartilage, fat, muscle, and neuron. Therefore, hMSC are attractive candidates for cell and gene therapy. The optimal conditions for hMSC expansion require medium supplemented with fetal bovine serum (FBS). Some forms of cell therapy will involve multiple doses, raising a concern over immunological reactions caused by medium-derived FBS proteins. In this study, we cultured human adipose stromal cells (hADSC) and bone marrow stroma cells (HBMSC) in human serum (HS) during their isolation and expansion, and demonstrated that they maintain their proliferative capacity and ability for multilineage differentiation and promote engraftment of peripheral blood-derived CD34(+) cells mobilized from bone marrow in NOD/SCID mice. Our results indicate that hADSC and hBMSC cultured in HS can be used for clinical trials of cell and gene therapies, including promotion of engraftment after allogeneic HSC transplantation

The inhibition, reactivation and mechanism of VX-, sarin-, fluoro-VX and fluoro-sarin surrogates following their interaction with HuAChE and HuBuChE.

Science.gov (United States)

Chao, Chih-Kai; Balasubramanian, Narayanaganesh; Gerdes, John M; Thompson, Charles M

2018-06-16

In this study, the mechanisms of HuAChE and HuBChE inhibition by Me-P(O) (OPNP) (OR) [PNP = p-nitrophenyl; R = CH 2 CH 3 , CH 2 CH 2 F, OCH(CH 3 ) 2 , OCH(CH 3 ) (CH 2 F)] representing surrogates and fluoro-surrogates of VX and sarin were studied by in vitro kinetics and mass spectrometry. The in vitro measures showed that the VX- and fluoro-VX surrogates were relatively strong inhibitors of HuAChE and HuBChE (k i  ∼ 10 5 -10 6  M -1 min -1 ) and underwent spontaneous and 2-PAM-mediated reactivation within 30 min. The sarin surrogates were weaker inhibitors of HuAChE and HuBChE (k i  ∼ 10 4 -10 5  M -1 min -1 ), and in general did not undergo spontaneous reactivation, although HuAChE adducts were partially reactivatable at 18 h using 2-PAM. The mechanism of HuAChE and HuBChE inhibition by the surrogates was determined by Q-TOF and MALDI-TOF mass spectral analyses. The surrogate-adducted proteins were trypsin digested and the active site-containing peptide bearing the OP-modified serine identified by Q-TOF as triply- and quadruply-charged ions representing the respective increase in mass of the attached OP moiety. Correspondingly, monoisotopic ions of the tryptic peptides representing the mass increase of the OP-adducted peptide was identified by MALDI-TOF. The mass spectrometry analyses validated the identity of the OP moiety attached to HuAChE or HuBChE as MeP(O) (OR)-O-serine peptides (loss of the PNP leaving group) via mechanisms consistent with those found with chemical warfare agents. MALDI-TOF MS analyses of the VX-modified peptides versus time showed a steady reduction in adduct versus parent peptide (reactivation), whereas the sarin-surrogate-modified peptides remained largely intact over the course of the experiment (24 h). Overall, the presence of a fluorine atom on the surrogate modestly altered the rate constants of inhibition and reactivation, however, the mechanism of inhibition (ejection of PNP group) did not change

Teaching PBL with Web 2.0

DEFF Research Database (Denmark)

Dohn, Nina Bonderup; Buus, Lillian

2013-01-01

Web 2.0-mediated learning activities are associated with a number of potentials for learning. Among these potentials are pedagogical advantages connected with bottom-up user-generation of content; opportunities for organizing flexible learning; and possibilities of supporting the development...... of competences necessary for participating in contemporary society. In this article we report on a study of three cases where web 2.0 activities have been introduced into PBL settings. Our focus is the unexpected challenges teachers may face due to inherent tensions between the practice logic of the educational...... system and that of web 2.0-practices. The study documents the development of viable ways of making use of web 2.0-mediated activities in support of a PBL approach and thus provides existence proof that web 2.0 activities may contribute constructively and productively to learning within a PBL perspective...

SupT1 Cell Infusion as a Possible Cell-Based Therapy for HIV: Results from a Pilot Study in Hu-PBMC BRGS Mice

Directory of Open Access Journals (Sweden)

Jonathan Fior

2016-04-01

Full Text Available In a previous in vitro study, the SupT1 cell line was explored as a decoy target for HIV-1, proposing SupT1 cell infusion as a possible cell-based therapy for HIV. In the present work, the previous in vitro model was translated into an in vivo setting. Specifically, Hu-PBMC BRGS mice were infected with a high input of HIV-1 LAI (100,000 TCID50, and 40 million 30 Gy-irradiated SupT1 cells were infused weekly for 4 weeks as a therapy. Blood samples were taken to monitor CD4+ T cell count and viral load, and mice were monitored daily for signs of illness. At the earliest time point analyzed (Week 1, there was a significantly lower plasma viral load (~10-fold in all animals treated with SupT1 cell infusion, associated with a higher CD4+ T cell count. At later time points, infection proceeded with robust viral replication and evident CD4+ T cell depletion, except in one mouse that showed complete suppression of viral replication and preservation of CD4+ T cell count. No morbidity or mortality was associated with SupT1 cell infusion. The interesting tendencies observed in the generated data suggest that this approach should be further investigated as a possible cell-based HIV therapy.

Visualizing the prostate gland by MR imaging in young and old mice.

Directory of Open Access Journals (Sweden)

Murali Ravoori

Full Text Available Prostate imaging requires optimization in young and old mouse models. We tested which MR sequences and field strengths best depict the prostate gland in young and old mice; and, whether prostate MR signal, size, and architecture change with age.Magnetic resonance imaging (MRI of the prostate of young (2 months and old (18 months male nude mice (n = 6 was performed at 4.7 and 7 T and SCID mice (n = 6 at 7 T field strengths, using T1, fat suppressed T1, DWI, T2, fat suppressed T2, as well as T2-based- and proton density-based Dixon "water only" sequences. Images were ranked for best overall sequence for prostate visualization, prostate delineation, and quality of fat suppression. Prostate volume and signal characteristics were compared and histology was performed.T2-based-Dixon "water only" images ranked best overall for prostate visualization and delineation as well as fat suppression (n = 6, P<0.001 at both 4.7 T and 7 T in nude and 7T in SCID mice. Evaluated in nude mice, T2-based Dixon "water only" had greater prostate CNR and lower fat SNR at 7 T than 4.7 T (P<0.001. Prostate volume was less in older than younger mice (n = 6, P<0.02 nude mice; n = 6, P<0.002 SCID mice. Prostate T2 FSE as well as proton density-based and T2-based-Dixon "water only" signal intensity was higher in younger than older mice (P<0.001 nude mice; P<0.01 SCID mice both at 4.7 and 7 T. This corresponded to an increase in glandular hyperplasia in older mice by histology (P<0.01, n = 6.T2-based Dixon "water only" images best depict the mouse prostate in young and old nude mice at 4.7 and 7 T. The mouse prostate decreases in size with age. The decrease in T2 and T2-based Dixon "water only" signal with age corresponds with glandular hyperplasia. Findings suggest age should be an important determinant when choosing models of prostate biology and disease.

Introducing PBL to Foreign Studentsin International Engineering Programs

DEFF Research Database (Denmark)

Du, Xiangyun; Dahms, Mona-Lisa; Jensen, Lars Peter

2007-01-01

programs to develop process competencies from an intercultural perspective. The POL course has had positive effects in terms of helping foreign students understand PBL and develop learning strategies in a PBL setting. However, our experiences show that issues arising from cultural diversity in educational...... to develop process competencies (i.e. skills in project management, collaboration, communication, etc.) in addition to technical skills. This paper presents the development of a course, the Project Organized Learning (POL) course, which has been designed to assist students in international engineering...... settings are more complex than only integrating foreign students into existing programs. More efforts and better strategies are needed to improve intercultural competencies for teaching staff and students, foreigners as well as locals, in engineering education....

Kids as Airborne Mission Scientists: Designing PBL To Inspire Kids.

Science.gov (United States)

Koszalka, Tiffany A.; Grabowski, Barbara L.; Kim, Younghoon

Problem-based learning (PBL) has great potential for inspiring K-12 learning. KaAMS, a NASA funded project and an example of PBL, was designed to help teachers inspire middle school students to learn science. The students participate as scientists investigating environmental problems using NASA airborne remote sensing data. Two PBL modules were…

An experiment with PBL in higher education as appraised by the teacher and students

Directory of Open Access Journals (Sweden)

Luis Roberto de Camargo Ribeiro

2006-01-01

Full Text Available PBL (Problem-based Learning has gained worldwide acceptance as an effective instructional approach that helps students to acquire knowledge as well as develop desired professional skills and attitudes. Contrary to other conventional methods that use problems after theory has been introduced, PBL uses a problem to initiate, focus and motivate the learning of new concepts. This paper presents and discusses the students' and the teacher's viewpoints on the implementation of PBL in an Administration Theory course of an engineering curriculum at a public university in Brazil. The data were collected by means of unstructured interviews, participant observation and an open-ended questionnaire responded by the students at the end of the course. The results show that despite increasing the workload for the teacher and the students, both evaluated PBL positively because it is more motivating and dynamic.

An experiment with PBL in higher education as appraised by the teacher and students

Directory of Open Access Journals (Sweden)

Luis Roberto de Camargo Ribeiro

2005-08-01

Full Text Available PBL (Problem-based Learning has gained worldwide acceptance as an effective instructional approach that helps students to acquire knowledge as well as develop desired professional skills and attitudes. Contrary to other conventional methods that use problems after theory has been introduced, PBL uses a problem to initiate, focus and motivate the learning of new concepts. This paper presents and discusses the students' and the teacher's viewpoints on the implementation of PBL in an Administration Theory course of an engineering curriculum at a public university in Brazil. The data were collected by means of unstructured interviews, participant observation and an open-ended questionnaire responded by the students at the end of the course. The results show that despite increasing the workload for the teacher and the students, both evaluated PBL positively because it is more motivating and dynamic.

Synthetic miR-34a mimics as a novel therapeutic agent for multiple myeloma: in vitro and in vivo evidence.

Science.gov (United States)

Di Martino, Maria T; Leone, Emanuela; Amodio, Nicola; Foresta, Umberto; Lionetti, Marta; Pitari, Maria R; Cantafio, Maria E Gallo; Gullà, Annamaria; Conforti, Francesco; Morelli, Eugenio; Tomaino, Vera; Rossi, Marco; Negrini, Massimo; Ferrarini, Manlio; Caraglia, Michele; Shammas, Masood A; Munshi, Nikhil C; Anderson, Kenneth C; Neri, Antonino; Tagliaferri, Pierosandro; Tassone, Pierfrancesco

2012-11-15

Deregulated expression of miRNAs has been shown in multiple myeloma (MM). A promising strategy to achieve a therapeutic effect by targeting the miRNA regulatory network is to enforce the expression of miRNAs that act as tumor suppressor genes, such as miR-34a. Here, we investigated the therapeutic potential of synthetic miR-34a against human MM cells in vitro and in vivo. Either transient expression of miR-34a synthetic mimics or lentivirus-based miR-34a-stable enforced expression triggered growth inhibition and apoptosis in MM cells in vitro. Synthetic miR-34a downregulated canonic targets BCL2, CDK6, and NOTCH1 at both the mRNA and protein level. Lentiviral vector-transduced MM xenografts with constitutive miR-34a expression showed high growth inhibition in severe combined immunodeficient (SCID) mice. The anti-MM activity of lipidic-formulated miR-34a was further shown in vivo in two different experimental settings: (i) SCID mice bearing nontransduced MM xenografts; and (ii) SCID-synth-hu mice implanted with synthetic 3-dimensional scaffolds reconstituted with human bone marrow stromal cells and then engrafted with human MM cells. Relevant tumor growth inhibition and survival improvement were observed in mice bearing TP53-mutated MM xenografts treated with miR-34a mimics in the absence of systemic toxicity. Our findings provide a proof-of-principle that formulated synthetic miR-34a has therapeutic activity in preclinical models and support a framework for development of miR-34a-based treatment strategies in MM patients. ©2012 AACR.

Learning about Severe Combined Immunodeficiency (SCID)

Science.gov (United States)

... immunodeficiency From The Journal of Allergy and Clinical Immunology Learning About Severe Combined Immunodeficiency (SCID) What is ... immunodeficiency From The Journal of Allergy and Clinical Immunology Get Email Updates Privacy Copyright Contact Accessibility Plug- ...

The Effectiveness of Problem Based Learning (PBL on Intermediate Financial Accounting Subject

Directory of Open Access Journals (Sweden)

Nunuk Suryanti

2016-12-01

Full Text Available This research aims to know the effectiveness of Problem Based Learning (PBL Model comparing to Drill Model on Intermediate Financial Accounting subject. The research was a quasi-experimental research. Population was four classes of Accounting Education students in the year of 2014/2015 at Faculty of Educational Science and Teaching of Riau Islamic University (UIR. Sample was taken by using purposive sampling. Then, it used Problem Based Learning (PBL at experimental class and Drill Model at controlled class. Data was collected by using interview, observation, and tests (pre-test and post-test. Moreover, data were analyzed by using independent sample test. Findings show that there is no any difference of learning outcomes between students who taught by Problem Based Learning (PBL Model and Drill Model on Intermediate Financial Accounting.

Implementation of Problem Based Learning (PBL) - in a Malaysian Teacher Education Course

DEFF Research Database (Denmark)

Borhan, Mohamad Termizi Bin; Yassin, Sopia Md

2013-01-01

The paper describes an employment of a Problem Based Learning (PBL) approach in a Malaysian graduate teacher education course. The discussions focus on how PBL was introduced, the PBL tasks and explore issues and benefits perceived by students. Data were obtained from journal reflections......, interviews and field note of observations. All types of data were analyze using inductive analytical approach. The result indicated that students were struggling at the preliminary phase of PBL, require more time in PBL learning process and link the acquisition of skills and group working process as benefits...

Hyperbilirubinemia and rapid fatal hepatic failure in severe combined immunodeficiency caused by adenosine deaminase deficiency (ADA-SCID).

Science.gov (United States)

Kühl, J S; Schwarz, K; Münch, A; Schmugge, M; Pekrun, A; Meisel, C; Wahn, V; Ebell, W; von Bernuth, H

2011-03-01

Adenosin deaminase (ADA) deficiency is the cause for Severe Combined Immunodeficiency (SCID) in about 15% of patients with SCID, often presenting as T (-)B (-)NK (-)SCID. Treatment options for ADA-SCID are enzyme replacement, bone marrow transplantation or gene therapy. We here describe the first patient with ADA-SCID and fatal hepatic failure despite bone marrow transplantation from a 10/10 HLA identical related donor. As patients with ADA-SCID may be at yet underestimated increased risk for rapid hepatic failure we speculate whether hepatitis in ADA-SCID should lead to the immediate treatment with enzyme replacement by pegylated ADA. © Georg Thieme Verlag KG Stuttgart · New York.

Development of a Survey to Examine the Factors that Motivate Secondary Education Teachers' Use of Problem-based Learning (PBL)

Science.gov (United States)

Lao, Huei-Chen

In this quantitative study, a survey was developed and administered to middle and high school teachers to examine what factors motivated them to implement problem-based learning (PBL). Using Expectancy-Value Theory by Eccles et al. (1983) and Self-Determination Theory by Ryan and Deci (2000b) as the theoretical framework, this instrument measured respondents' perceived competence, support for autonomy and relatedness, and value and cost they placed on implementing PBL. Data analyses indicated that the instrument had good reliability. A 3-factor structure was established by exploratory factor analysis which confirmed the construct validity of the instrument. Value of PBL to teachers and their students was the most dominant factor that motivated teachers to implement it. The second most important factor was their self-efficacy and anxiety about failing this pedagogy, and the third factor was teachers' perceived autonomy, and support from schools and colleagues. Regression models showed the predictive power of the factors on teachers' intention to implement PBL, with their perceptions of the value of PBL being the strongest predictor. Results also indicate that teachers with PBL experience perceived significantly higher levels of competence and support from peers, and placed a higher level of value and perceived less cost in implementing PBL than teachers who had not implemented PBL. Teachers' formal training in PBL played a significant role in positively influencing their perceptions of competence and the value of PBL, and reduced their perceived cost of implementing PBL. This, in turn, enhanced teachers' intention of practicing PBL. For teachers who had previously taught with PBL, their responses to two open-ended questions in this instrument corresponded with the theoretical framework of this study and triangulated well with the quantitative data. These teachers highly valued PBL and they recognized the challenges associated with its implementation. These teachers

Vicarious Learning in PBL Variants for Learning Electronics

Science.gov (United States)

Podges, Martin; Kommers, Piet

2017-01-01

Three different groups in a class of first-year tertiary engineering students had to solve a problem based on a project by applying the distinctive problem-based learning (PBL) approach. Each group's project (PBL project) was then studied by the other two groups after successful completion and demonstration. Each group then had to study the…

Enhancing Critical Thinking in a PBL Environment

DEFF Research Database (Denmark)

Guerra, Aida; Holgaard, Jette Egelund

2016-01-01

Engineering education accreditation bodies emphasize the need for competencies beyond technical expertise. Critical thinking is one of these competencies, which is also considered as a precursor for the development of other competencies such as multidisciplinary collaboration, problem......-solving skills and lifelong learning. There is an urgent need to enhance engineering students’ critical thinking and one way to do this is to make use of active, student-centred learning approaches such as Problem Based Learning (PBL). This study aims to provide a model for understanding and enhancing critical...... thinking in a PBL environment. The development of the model takes its point of departure from a conceptual model for critical thinking that is concretized in a PBL context by including theoretical as well as empirical perspectives. The empirical study was conducted at the Faculty of Engineering and Science...

Designing, implementing and evaluating an online problem-based learning (PBL) environment--a pilot study.

Science.gov (United States)

Ng, Manwa L; Bridges, Susan; Law, Sam Po; Whitehill, Tara

2014-01-01

Problem-based learning (PBL) has been shown to be effective for promoting student competencies in self-directed and collaborative learning, critical thinking, self-reflection and tackling novel situations. However, the need for face-to-face interactions at the same place and time severely limits the potential of traditional PBL. The requirements of space and for meeting at a specific location at the same time create timetabling difficulties. Such limitations need to be tackled before all potentials of PBL learning can be realized. The present study aimed at designing and implementing an online PBL environment for undergraduate speech/language pathology students, and assessing the associated pedagogical effectiveness. A group of eight PBL students were randomly selected to participate in the study. They underwent 4 weeks of online PBL using Adobe Connect. Upon completion of the experiment, they were assessed via a self-reported questionnaire and quantitative comparison with traditional PBL students based on the same written assignment. The questionnaire revealed that all participating students enjoyed online PBL, without any perceived negative effects on learning. Online PBL unanimously saved the students travel time to and from school. Statistical analysis indicated no significant difference in assignment grades between the online and traditional PBL groups, indicating that online PBL learning appears to be similarly effective as traditional face-to-face PBL learning.

Acute HBV infection in humanized chimeric mice has multiphasic viral kinetics.

Science.gov (United States)

Ishida, Yuji; Chung, Tje Lin; Imamura, Michio; Hiraga, Nobuhiko; Sen, Suranjana; Yokomichi, Hiroshi; Tateno, Chise; Canini, Laetitia; Perelson, Alan S; Uprichard, Susan L; Dahari, Harel; Chayama, Kazuaki

2018-03-23

Chimeric uPA/SCID mice reconstituted with humanized livers are useful for studying HBV infection in the absence of an adaptive immune response. However, the detailed characterization of HBV infection kinetics necessary to enable in-depth mechanistic studies in this novel in vivo HBV infection model is lacking. To characterize HBV kinetics post-inoculation (p.i.) to steady state, 42 mice were inoculated with HBV. Serum HBV DNA was frequently measured from 1 minute to 63 days p.i. Total intrahepatic HBV DNA, HBV cccDNA, and HBV RNA was measured in a subset of mice at 2, 4, 6, 10, and 13 weeks p.i. HBV half-life (t 1/2 ) was estimated using a linear mixed-effects model. During the first 6 h p.i. serum HBV declined in repopulated uPA/SCID mice with a t 1/2 =62 min [95%CI=59-67min]. Thereafter, viral decline slowed followed by a 2 day lower plateau. Subsequent viral amplification was multiphasic with an initial mean doubling time of t 2 =8±3 h followed by an interim plateau before prolonged amplification (t 2 =2±0.5 days) to a final HBV steady state of 9.3±0.3 log copies/ml. Serum HBV and intrahepatic HBV DNA were positively correlated (R 2 =0.98). HBV infection in uPA/SCID chimeric mice is highly dynamic despite the absence of an adaptive immune response. The serum HBV t 1/2 in humanized uPA/SCID mice was estimated to be ∼1 h regardless of inoculum size. The HBV acute infection kinetics presented here is an important step in characterizing this experimental model system so that it can be effectively used to elucidate the dynamics of the HBV lifecycle and thus possibly reveal effective antiviral drug targets. This article is protected by copyright. All rights reserved. © 2018 by the American Association for the Study of Liver Diseases.

Do Learners Like Project in Their English Classes?: Impact of PBL on Students’ Attitudes

Directory of Open Access Journals (Sweden)

Putri Astawa Ni Luh Putu Ning Septyarini

2018-01-01

Full Text Available This article presents the results of a study on the effect of Project-Based Learning (PBL on students’ English language learning (ELL attitudes and how the activities influence teaching-learning process in a junior high school in Bali. This research applied an embedded mixed-method design in which the quantitative data were collected using close-ended questionnaires test, and the qualitative data were collected using interview, observation checklist, open-ended questionnaire, and field note. Paired-samples t-test was used to analyse whether or not there is a significant effect on students’ attitude after being taught using PBL, while the qualitative data were analysed descriptively. The analysis shows a significant effect on students’ attitude. PBL enhances students’ learning quality in term of enthusiasm, confidence, and creativity learning ability while it also promotes teacher’s teaching satisfaction. This study supports the implementation of PBL which enhances students’ English Language Learning attitude and teaching-learning process.

Den danske udgave af Structured Clinical Interview for DSM-5 Personality Disorders (SCID-5-PD)

DEFF Research Database (Denmark)

Kongerslev, Mickey T; Bach, Bo; Olsen, Cecilie Westergaard

2017-01-01

The chapter outlines the rationale for using structured clinical interviews to diagnose personality disorder, provides an overview of the changes from SCID-II to SCID-5-PD, and describes the translation procedures used for the Danish version......The chapter outlines the rationale for using structured clinical interviews to diagnose personality disorder, provides an overview of the changes from SCID-II to SCID-5-PD, and describes the translation procedures used for the Danish version...

The Elav-like protein HuR exerts translational control of viral internal ribosome entry sites

International Nuclear Information System (INIS)

Rivas-Aravena, Andrea; Ramdohr, Pablo; Vallejos, Maricarmen; Valiente-Echeverria, Fernando; Dormoy-Raclet, Virginie; Rodriguez, Felipe; Pino, Karla; Holzmann, Cristian; Huidobro-Toro, J. Pablo; Gallouzi, Imed-Eddine; Lopez-Lastra, Marcelo

2009-01-01

The human embryonic-lethal abnormal vision (ELAV)-like protein, HuR, has been recently found to be involved in the regulation of protein synthesis. In this study we show that HuR participates in the translational control of the HIV-1 and HCV IRES elements. HuR functions as a repressor of HIV-1 IRES activity and acts as an activator of the HCV IRES. The effect of HuR was evaluated in three independent experimental systems, rabbit reticulocyte lysate, HeLa cells, and Xenopus laevis oocytes, using both overexpression and knockdown approaches. Furthermore, results suggest that HuR mediated regulation of HIV-1 and HCV IRESes does not require direct binding of the protein to the RNA nor does it need the nuclear translocation of the IRES-containing RNAs. Finally, we show that HuR has a negative impact on post-integration steps of the HIV-1 replication cycle. Thus, our observations yield novel insights into the role of HuR in the post-transcriptional regulation of HCV and HIV-1 gene expression.

An eLearning Standard Approach for Supporting PBL in Computer Engineering

Science.gov (United States)

Garcia-Robles, R.; Diaz-del-Rio, F.; Vicente-Diaz, S.; Linares-Barranco, A.

2009-01-01

Problem-based learning (PBL) has proved to be a highly successful pedagogical model in many fields, although it is not that common in computer engineering. PBL goes beyond the typical teaching methodology by promoting student interaction. This paper presents a PBL trial applied to a course in a computer engineering degree at the University of…

Partial correction of the dwarf phenotype by non-viral transfer of the growth hormone gene in mice: Treatment age is critical.

Science.gov (United States)

Higuti, Eliza; Cecchi, Cláudia R; Oliveira, Nélio A J; Lima, Eliana R; Vieira, Daniel P; Aagaard, Lars; Jensen, Thomas G; Jorge, Alexander A L; Bartolini, Paolo; Peroni, Cibele N

2016-02-01

Non-viral transfer of the growth hormone gene to different muscles of immunodeficient dwarf (lit/scid) mice is under study with the objective of improving phenotypic correction via this particular gene therapy approach. Plasmid DNA was administered into the exposed quadriceps or non-exposed tibialis cranialis muscle of lit/scid mice followed by electroporation, monitoring several growth parameters. In a 6-month bioassay, 50μg DNA were injected three times into the quadriceps muscle of 80-day old mice. A 50% weight increase, with a catch-up growth of 21%, together with a 16% increase for nose-to-tail and tail lengths (catch-up=19-21%) and a 24-28% increase for femur length (catch-up=53-60%), were obtained. mIGF1 serum levels were ~7-fold higher than the basal levels for untreated mice, but still ~2-fold lower than in non-dwarf scid mice. Since treatment age was found to be particularly important in a second bioassay utilizing 40-day old mice, these pubertal mice were compared in a third bioassay with adult (80-day old) mice, all treated twice with 50μg DNA injected into each tibialis cranialis muscle, via a less invasive approach. mIGF1 concentrations at the same level as co-aged scid mice were obtained 15days after administration in pubertal mice. Catch-up growth, based on femur length (77%), nose-to-tail (36%) and tail length (39%) increases was 40 to 95% higher than those obtained upon treating adult mice. These data pave the way for the development of more effective pre-clinical assays in pubertal dwarf mice for the treatment of GH deficiency via plasmid-DNA muscular administration. Copyright © 2015 Elsevier Ltd. All rights reserved.

Ebola Virus Replication and Disease Without Immunopathology in Mice Expressing Transgenes to Support Human Myeloid and Lymphoid Cell Engraftment.

Science.gov (United States)

Spengler, Jessica R; Lavender, Kerry J; Martellaro, Cynthia; Carmody, Aaron; Kurth, Andreas; Keck, James G; Saturday, Greg; Scott, Dana P; Nichol, Stuart T; Hasenkrug, Kim J; Spiropoulou, Christina F; Feldmann, Heinz; Prescott, Joseph

2016-10-15

The study of Ebola virus (EBOV) pathogenesis in vivo has been limited to nonhuman primate models or use of an adapted virus to cause disease in rodent models. Herein we describe wild-type EBOV (Makona variant) infection of mice engrafted with human hematopoietic CD34 + stem cells (Hu-NSG™-SGM3 mice; hereafter referred to as SGM3 HuMice). SGM3 HuMice support increased development of myeloid immune cells, which are primary EBOV targets. In SGM3 HuMice, EBOV replicated to high levels, and disease was observed following either intraperitoneal or intramuscular inoculation. Despite the high levels of viral antigen and inflammatory cell infiltration in the liver, the characteristic histopathology of Ebola virus disease was not observed, and this absence of severe immunopathology may have contributed to the recovery and survival of some of the animals. Future investigations into the underlying mechanisms of the atypical disease presentation in SGM3 HuMice will provide additional insights into the immunopathogenesis of severe EBOV disease. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

In vitro activated CD4+ T cells from interferon-gamma (IFN-gamma)-deficient mice induce intestinal inflammation in immunodeficient hosts

DEFF Research Database (Denmark)

Bregenholt, S; Brimnes, J; Nissen, Mogens Holst

1999-01-01

To investigate the role of IFN-gamma in the immunopathogenesis of inflammatory bowel disease (IBD), severe combined immunodeficient (SCID) mice were transplanted with in vitro activated CD4+ T cells from either wild-type (WT) or IFN-gamma-deficient (IFN-gammaKO) BALB/c mice. In vitro, the two types...... of T cells displayed comparable proliferation rates and production of tumour necrosis factor-alpha (TNF-alpha), IL-2, IL-4 and IL-10 after concanavalin A (Con A) stimulation. When transplanted into SCID mice, WT CD4+ blasts induced a lethal IBD, whereas IFN-gammaKO blasts induced a less severe...... intestinal inflammation with moderate weight loss. Intracellular cytokine staining of lamina propria lymphocytes (LPL) revealed comparable fractions of CD4+ T cells positive for TNF-alpha, IL-2 and IL-10 in the two groups of transplanted SCID mice, whereas a two-to-three-fold increase in the fraction of IL-4...

Genotype, Phenotype and Outcomes of Nine Patients with T-B+NK+ SCID

OpenAIRE

Yu, Grace P; Nadeau, Kari C; Berk, David R; de Saint Basile, Geneviève; Lambert, Nathalie; Knapnougel, Perrine; Roberts, Joseph; Kavanau, Kristina; Dunn, Elizabeth; Stiehm, E. Richard; Lewis, David B; Umetsu, Dale T; Puck, Jennifer M; Cowan, Morton J

2011-01-01

There are few reports of clinical presentation, genotype, and hematopoietic cell transplant (HCT) outcomes for T-B+NK+ SCID patients. Between 1981 and 2007, 8 of 84 SCID patients who received and/or were followed after HCT at UCSF had the T-B+NK+ phenotype. One additional T-B+NK+ SCID patient was identified as the sibling of a patient treated at UCSF. Chart reviews were performed. Molecular analyses of IL7R, IL2RG, JAK3 and the genes encoding the CD3 T-cell receptor components δ (CD3D), ε (CD...

Pengenalan Pose Tangan Menggunakan HuMoment

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Dina Budhi Utami

2017-02-01

Full Text Available Computer vision yang didasarkan pada pengenalan bentuk memiliki banyak potensi dalam interaksi manusia dan komputer. Pose tangan dapat dijadikan simbol interaksi manusia dengan komputer seperti halnya pada penggunaan berbagai pose tangan pada bahasa isyarat. Berbagai pose tangan dapat digunakan untuk menggantikan fungsi mouse, untuk mengendalikan robot, dan sebagainya. Penelitian ini difokuskan pada pembangunan sistem pengenalan pose tangan menggunakan HuMoment. Proses pengenalan pose tangan dimulai dengan melakukan segmentasi citra masukan untuk menghasilkan citra ROI (Region of Interest yaitu area telapak tangan. Selanjutnya dilakukan proses deteksi tepi. Kemudian dilakukan ekstraksi nilai HuMoment. Nilai HuMoment dikuantisasikan ke dalam bukukode yang dihasilkan dari proses pelatihan menggunakan K-Means. Proses kuantisasi dilakukan dengan menghitung nilai Euclidean Distance terkecil antara nilai HuMomment citra masukan dan bukukode. Berdasarkan hasil penelitian, nilai akurasi sistem dalam mengenali pose tangan adalah 88.57%.

Alterations in the brain adenosine metabolism cause behavioral and neurological impairment in ADA-deficient mice and patients

Science.gov (United States)

Sauer, Aisha V.; Hernandez, Raisa Jofra; Fumagalli, Francesca; Bianchi, Veronica; Poliani, Pietro L.; Dallatomasina, Chiara; Riboni, Elisa; Politi, Letterio S.; Tabucchi, Antonella; Carlucci, Filippo; Casiraghi, Miriam; Carriglio, Nicola; Cominelli, Manuela; Forcellini, Carlo Alberto; Barzaghi, Federica; Ferrua, Francesca; Minicucci, Fabio; Medaglini, Stefania; Leocani, Letizia; la Marca, Giancarlo; Notarangelo, Lucia D.; Azzari, Chiara; Comi, Giancarlo; Baldoli, Cristina; Canale, Sabrina; Sessa, Maria; D’Adamo, Patrizia; Aiuti, Alessandro

2017-01-01

Adenosine Deaminase (ADA) deficiency is an autosomal recessive variant of severe combined immunodeficiency (SCID) caused by systemic accumulation of ADA substrates. Neurological and behavioral abnormalities observed in ADA-SCID patients surviving after stem cell transplantation or gene therapy represent an unresolved enigma in the field. We found significant neurological and cognitive alterations in untreated ADA-SCID patients as well as in two groups of patients after short- and long-term enzyme replacement therapy with PEG-ADA. These included motor dysfunction, EEG alterations, sensorineural hypoacusia, white matter and ventricular alterations in MRI as well as a low mental development index or IQ. Ada-deficient mice were significantly less active and showed anxiety-like behavior. Molecular and metabolic analyses showed that this phenotype coincides with metabolic alterations and aberrant adenosine receptor signaling. PEG-ADA treatment corrected metabolic adenosine-based alterations, but not cellular and signaling defects, indicating an intrinsic nature of the neurological and behavioral phenotype in ADA deficiency. PMID:28074903

PBL and CDIO: Complementary Models for Engineering Education Development

Science.gov (United States)

Edström, Kristina; Kolmos, Anette

2014-01-01

This paper compares two models for reforming engineering education, problem/project-based learning (PBL), and conceive-design-implement-operate (CDIO), identifying and explaining similarities and differences. PBL and CDIO are defined and contrasted in terms of their history, community, definitions, curriculum design, relation to disciplines,…

PBL and CDIO: complementary models for engineering education development

Science.gov (United States)

Edström, Kristina; Kolmos, Anette

2014-09-01

This paper compares two models for reforming engineering education, problem/project-based learning (PBL), and conceive-design-implement-operate (CDIO), identifying and explaining similarities and differences. PBL and CDIO are defined and contrasted in terms of their history, community, definitions, curriculum design, relation to disciplines, engineering projects, and change strategy. The structured comparison is intended as an introduction for learning about any of these models. It also invites reflection to support the understanding and evolution of PBL and CDIO, and indicates specifically what the communities can learn from each other. It is noted that while the two approaches share many underlying values, they only partially overlap as strategies for educational reform. The conclusions are that practitioners have much to learn from each other's experiences through a dialogue between the communities, and that PBL and CDIO can play compatible and mutually reinforcing roles, and thus can be fruitfully combined to reform engineering education.

Comparison the Application of PBL (Project Based Learning and PBL (Problem Based Learning Learning Model on Online Marketing Subjects

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Agnes Dini Mardani

2017-09-01

Full Text Available Purpose of this study are (1 the application of learning PjBL with PBL to improve study results students, (2 assessing the domain affective, cognitive, and psychomotor, (3 the difference study results use the PjBL with PBL to improve study results students. The research is research quantitative and including research apparent experiment (quasi eksperiment by taking sample class two classes X PM 1 as a class experiment and class X PM 2 as a class control. Research instruments used for data collection namely: (1 tests to pretes and postest used to determine the cognitive assessment, (2 sheets observation affective, (3 sheets of the process for the psychomotor. The trial research instruments use the validity and reabilitas. Analysis techniques data using: (1 test a prerequisite analysis consisting of normality test and the homogeneity (2 T test unpaired which ended with the help of computer programs spss. Based on the result of this research can be concluded that: (1 the application of PjBL (Project Based Learning and PBL (Problem Based Learning should be conducted well in accordance syntax learning, (2 assessing the cognitive students have a difference and class experiment having an average higher than class control, (3 assessing the results affective students have a difference and on the application of PjBL is better than PBL.

Long-term leukocyte reconstitution in NSG mice transplanted with human cord blood hematopoietic stem and progenitor cells.

Science.gov (United States)

Audigé, Annette; Rochat, Mary-Aude; Li, Duo; Ivic, Sandra; Fahrny, Audrey; Muller, Christina K S; Gers-Huber, Gustavo; Myburgh, Renier; Bredl, Simon; Schlaepfer, Erika; Scherrer, Alexandra U; Kuster, Stefan P; Speck, Roberto F

2017-05-30

Humanized mice (hu mice) are based on the transplantation of hematopoietic stem and progenitor cells into immunodeficient mice and have become important pre-clinical models for biomedical research. However, data about their hematopoiesis over time are scarce. We therefore characterized leukocyte reconstitution in NSG mice, which were sublethally irradiated and transplanted with human cord blood-derived CD34+ cells at newborn age, longitudinally in peripheral blood and, for more detailed analyses, cross-sectionally in peripheral blood, spleen and bone marrow at different time points. Human cell chimerism and absolute human cell count decreased between week 16 and 24 in the peripheral blood of hu mice, but were stable thereafter as assessed up to 32 weeks. Human cell chimerism in spleen and bone marrow was maintained over time. Notably, human cell chimerism in peripheral blood and spleen as well as bone marrow positively correlated with each other. Percentage of B cells decreased between week 16 and 24, whereas percentage of T cells increased; subsequently, they levelled off with T cells clearly predominating at week 32. Natural killer cells, monocytes and plasmacytoid dendritic cells (DCs) as well as CD1c + and CD141+ myeloid DCs were all present in hu mice. Proliferative responses of splenic T cells to stimulation were preserved over time. Importantly, the percentage of more primitive hematopoietic stem cells (HSCs) in bone marrow was maintained over time. Overall, leukocyte reconstitution was maintained up to 32 weeks post-transplantation in our hu NSG model, possibly explained by the maintenance of HSCs in the bone marrow. Notably, we observed great variation in multi-lineage hematopoietic reconstitution in hu mice that needs to be taken into account for the experimental design with hu mice.

Hyper-radiation sensitivity of murine scid mutation and mapping of the human homologue HYRC1 gene

International Nuclear Information System (INIS)

Komatsu, Kenshi; Ohta, Tohru; Niikawa, Norio; Okumura, Yutaka; Kubota, Nobuo.

1994-01-01

The murine severe combined immunodeficient mutation (scid) is characterized by a lack of both B and T cells, due to a defect in lymphoid variable-(diversity)-joining(V(D)J) rearrangement. Scid cells are highly sensitive to both radiation-induced killing and chromosomal aberrations. Present experiments also demonstrated the high sensitivity of scid cells to killing, because of a deficient repair of double strand breaks(DSB). Scid cells can repair only 60% of radiation-induced DSB for 3 hours, while normal cells repair 85% of the DSB. Significantly reduced Do and n values were obtained from survival curves of scid cells and were similar to ataxia-telangiectasia(AT) cells (a unique human disease conferring whole body radiosensitivity). However, the kinetics of DNA synthesis after irradiation were different between the two cell types. In contrast with the radioresistant DNA synthesis of AT cells, DNA synthesis of scid cells was markedly inhibited after irradiation. The existence of different mutations was also supported by evidence of complementation in somatic cell hybrids between scid cells and AT cells. Using these hybrid cells, fragments of human chromosome 8 were introduced into scid cells HPRT mutant via X-irradiation and somatic cell fusion. The resulting hybrid clones contained human DNA fragment(s) which complemented the hyper-radiosensitivity of the scid cells. Alu-PCR products from these hybrids were used for chromosome painting using the technique of chromosome in situ suppression hybridization, allowing assignment of the human HYRC1 (hyper-radiosensitivity of murine scid mutation, complementing 1) gene, a candidate for a V(D)J recombinant gene, to human chromosome 8q11. (author)

Sparks sädeleb Rabarocki öös. Ettevaatust! Eliidi rünnak. Hu? Hu da hell?

Index Scriptorium Estoniae

2007-01-01

Ameerika ansamblist Sparks. Vaiko Eplik & Eliit heliplaatidest "1: Aastaajad", "2: Aastaajad" ja "3: Kosmoseodüsseia", esinemisest festivalil Rabarock. Hannaliisa Uusma, Leslie Da Bassi ja DJ Criticali projektist HU?, singlitest "Kosmos" ja "Absoluutselt" (Rabarockil esitusel materjal HU? debüütalbumilt "Film")

Journey into the Problem-Solving Process: Cognitive Functions in a PBL Environment

Science.gov (United States)

Chua, B. L.; Tan, O. S.; Liu, W. C.

2016-01-01

In a PBL environment, learning results from learners engaging in cognitive processes pivotal in the understanding or resolution of the problem. Using Tan's cognitive function disc, this study examines the learner's perceived cognitive functions at each stage of PBL, as facilitated by the PBL schema. The results suggest that these learners…

Activity of nucleic acid polymers in rodent models of HBV infection.

Science.gov (United States)

Schöneweis, Katrin; Motter, Neil; Roppert, Pia L; Lu, Mengji; Wang, Baoju; Roehl, Ingo; Glebe, Dieter; Yang, Dongliang; Morrey, John D; Roggendorf, Michael; Vaillant, Andrew

2018-01-01

Nucleic acid polymers (NAPs) block the release of HBsAg from infected hepatocytes. These compounds have been previously shown to have the unique ability to eliminate serum surface antigen in DHBV-infected Pekin ducks and achieve multilog reduction of HBsAg or HBsAg loss in patients with chronic HBV infection and HBV/HDV coinfection. In ducks and humans, the blockage of HBsAg release by NAPs occurs by the selective targeting of the assembly and/or secretion of subviral particles (SVPs). The clinically active NAP species REP 2055 and REP 2139 were investigated in other relevant animal models of HBV infection including woodchucks chronically infected with WHV, HBV transgenic mice and HBV infected SCID-Hu mice. The liver accumulation of REP 2139 in woodchucks following subcutaneous administration was examined and was found to be similar to that observed in mice and ducks. However, in woodchucks, NAP treatment was associated with only mild (36-79% relative to baseline) reductions in WHsAg (4/10 animals) after 3-5 weeks of treatment without changes in serum WHV DNA. In HBV infected SCID-Hu mice, REP 2055 treatment was not associated with any reduction of HBsAg, HBeAg or HBV DNA in the serum after 28 days of treatment. In HBV transgenic mice, no reductions in serum HBsAg were observed with REP 2139 with up to 12 weeks of treatment. In conclusion, the antiviral effects of NAPs in DHBV infected ducks and patients with chronic HBV infection were weak or absent in woodchuck and mouse models despite similar liver accumulation of NAPs in all these species, suggesting that the mechanisms of SVP assembly and or secretion present in rodent models differs from that in DHBV and chronic HBV infections. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

NOD/scid IL-2Rgnull mice: a preclinical model system to evaluate human dendritic cell-based vaccine strategies in vivo

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Spranger Stefani

2012-02-01

Full Text Available Abstract Background To date very few systems have been described for preclinical investigations of human cellular therapeutics in vivo. However, the ability to carry out comparisons of new cellular vaccines in vivo would be of substantial interest for design of clinical studies. Here we describe a humanized mouse model to assess the efficacy of various human dendritic cell (DC preparations. Two reconstitution regimes of NOD/scid IL2Rgnull (NSG mice with adult human peripheral blood mononuclear cells (PBMC were evaluated for engraftment using 4-week and 9-week schedules. This led to selection of a simple and rapid protocol for engraftment and vaccine evaluation that encompassed 4 weeks. Methods NSG recipients of human PBMC were engrafted over 14 days and then vaccinated twice with autologous DC via intravenous injection. Three DC vaccine formulations were compared that varied generation time in vitro (3 days versus 7 days and signals for maturation (with or without Toll-like receptor (TLR3 and TLR7/8 agonists using MART-1 as a surrogate antigen, by electroporating mature DC with in vitro transcribed RNA encoding full length protein. After two weekly vaccinations, the splenocyte populations containing human lymphocytes were recovered 7 days later and assessed for MART-1-specific immune responses using MHC-multimer-binding assays and functional assessment of specific killing of melanoma tumor cell lines. Results Human monocyte-derived DC generated in vitro in 3 days induced better MART-1-specific immune responses in the autologous donor T cells present in the humanized NSG mice. Moreover, consistent with our in vitro observations, vaccination using mature DC activated with TLR3 and TLR7/8 agonists resulted in enhanced immune responses in vivo. These findings led to a ranking of the DC vaccine effects in vivo that reflected the hierarchy previously found for these mature DC variations in vitro. Conclusions This humanized mouse model system enables

Metacognição em Grupos de Problem-based Learning (PBL

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Adriana Vargas

2017-08-01

Full Text Available Aprendizagem em grupo é um processo que envolve a mobilização de funções cognitivas e desenvolve competências necessárias no decorrer da vida. A Problem-based Learning (PBL, uma proposta de aprendizagem em grupo, enfatiza o desenvolvimento cognitivo e pode potencializar a metacognição. Objetivou-se responder as questões: 1 a PBL é uma metodologia que envolve o desenvolvimento da metacognição? 2 pode-se relacionar os estudos da metacognição no contexto grupal à PBL? Realizou-se o estado do conhecimento do tema, entre 2010 a 2015, contendo os termos metacognition e Problem-based Learning, no portal de periódicos da CAPES. Oito pesquisas foram selecionadas por descreverem evidências empíricas da metacognição em grupos de PBL. A PBL pode ser aplicada aos estudos de aprendizagem em grupo e metacognição, por mobilizar conhecimentos, a tomada de consciência e o autocontrole.

Motivation, Challenges, Support (MCS) Cycle Model for the Development of PBL Tutors

Science.gov (United States)

Constantinou, Costas S.; Nicolaou, Stella A.

2018-01-01

Problem-Based Learning (PBL) is well known for enhancing students' problem solving skills and teamwork, while the role of PBL tutors is to facilitate discussion rather than teach. This study used four focus groups to explore PBL tutors' motivation, challenges and support mechanisms, and the relationship between these. The study found that there…

Somatic mosaicism caused by monoallelic reversion of a mutation in T cells of a patient with ADA-SCID and the effects of enzyme replacement therapy on the revertant phenotype.

Science.gov (United States)

Moncada-Vélez, M; Vélez-Ortega, A; Orrego, J; Santisteban, I; Jagadeesh, J; Olivares, M; Olaya, N; Hershfield, M; Candotti, F; Franco, J

2011-11-01

Patients with adenosine deaminase (ADA) deficiency exhibit spontaneous and partial clinical remission associated with somatic reversion of inherited mutations. We report a child with severe combined immunodeficiency (T-B- SCID) due to ADA deficiency diagnosed at the age of 1 month, whose lymphocyte counts including CD4+ and CD8+ T and NK cells began to improve after several months with normalization of ADA activity in Peripheral blood lymphocytes (PBL), as a result of somatic mosaicism caused by monoallelic reversion of the causative mutation in the ADA gene. He was not eligible for haematopoietic stem cell transplantation (HSCT) or gene therapy (GT); therefore he was placed on enzyme replacement therapy (ERT) with bovine PEG-ADA. The follow-up of metabolic and immunologic responses to ERT included gradual improvement in ADA activity in erythrocytes and transient expansion of most lymphocyte subsets, followed by gradual stabilization of CD4+ and CD8+ T (with naïve phenotype) and NK cells, and sustained expansion of TCRγδ+ T cells. This was accompanied by the disappearance of the revertant T cells as shown by DNA sequencing from PBL. Although the patient's clinical condition improved marginally, he later developed a germinal cell tumour and eventually died at the age of 67 months from sepsis. This case adds to our current knowledge of spontaneous reversion of mutations in ADA deficiency and shows that the effects of the ERT may vary among these patients, suggesting that it could depend on the cell and type in which the somatic mosaicism is established upon reversion. © 2011 The Authors. Scandinavian Journal of Immunology © 2011 Blackwell Publishing Ltd.

Microenvironment-dependent phenotypic changes in a SCID mouse model for malignant mesothelioma

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Eva eDarai-Ramqvist

2013-08-01

Full Text Available Background and Aims: Malignant mesothelioma is an aggressive, therapy-resistant tumor. Mesothelioma cells may assume an epithelioid or a sarcomatoid phenotype, and presence of sarcomatoid cells predicts poor prognosis. In this study, we investigated differentiation of mesothelioma cells in a xenograft model, where mesothelioma cells of both phenotypes were induced to form tumors in SCID mice. Methods: Xenografts were established and thoroughly characterized using a comprehensive immunohistochemical panel, array comparative genomic hybridization of chromosome 3, fluorescent in situ hybridization and electron microscopy.Results: Epithelioid and sarcomatoid cells gave rise to xenografts of similar epithelioid morphology. While sarcomatoid-derived xenografts had higher growth rates, the morphology and expression of differentiation-related markers was similar between xenografts derived from both phenotypes. Array comparative genomic hybridization showed a convergent genotype for both xenografts, resembling the original aggressive sarcomatoid cell sub-line.Conclusions: Human mesothelioma xenografts from sarcomatoid and epithelioid phenotypes converged to a similar differentiation state, and genetic analyses suggested that clonal selection in the mouse microenvironment was a major contributing factor. This thoroughly characterized animal model can be used for further studies of molecular events underlying tumor cell differentiation.

PBL at Aalborg university

DEFF Research Database (Denmark)

From the preface: "All the articles in this book have been presented at the International Conference PBL 2006 ABP, that was held in Lima, Peru, July 19th-21th 2006. This conference is part of a series of Pan-American conferences. It is the first time that Aalborg University has participated...

Ex vivo expanded human regulatory T cells delay islet allograft rejection via inhibiting islet-derived monocyte chemoattractant protein-1 production in CD34+ stem cells-reconstituted NOD-scid IL2rγnull mice.

Science.gov (United States)

Xiao, Fang; Ma, Liang; Zhao, Min; Huang, Guocai; Mirenda, Vincenzo; Dorling, Anthony; Lechler, Robert; Lombardi, Giovanna

2014-01-01

Type 1 diabetes mellitus (T1DM) is an autoimmune disease caused by immune-mediated destruction of insulin-secreting β cells of the pancreas. Near complete dependence on exogenous insulin makes T1DM very difficult to control, with the result that patients are exposed to high blood glucose and risk of diabetic complications and/or intermittent low blood glucose that can cause unconsciousness, fits and even death. Allograft transplantation of pancreatic islets restores normoglycemia with a low risk of surgical complications. However, although successful immediately after transplantation, islets are progressively lost, with most of the patients requiring exogenous insulin within 2 years post-transplant. Therefore, there is an urgent requirement for the development of new strategies to prevent islet rejection. In this study, we explored the importance of human regulatory T cells in the control of islets allograft rejection. We developed a pre-clinical model of human islet transplantation by reconstituting NOD-scid IL2rγnull mice with cord blood-derived human CD34+ stem cells and demonstrated that although the engrafted human immune system mediated the rejection of human islets, their survival was significantly prolonged following adoptive transfer of ex vivo expanded human Tregs. Mechanistically, Tregs inhibited the infiltration of innate immune cells and CD4+ T cells into the graft by down-regulating the islet graft-derived monocyte chemoattractant protein-1. Our findings might contribute to the development of clinical strategies for Treg therapy to control human islet rejection. We also show for the first time that CD34+ cells-reconstituted NOD-scid IL2rγnull mouse model could be beneficial for investigating human innate immunity in vivo.

Ex Vivo Expanded Human Regulatory T Cells Delay Islet Allograft Rejection via Inhibiting Islet-Derived Monocyte Chemoattractant Protein-1 Production in CD34+ Stem Cells-Reconstituted NOD-scid IL2rγnull Mice

Science.gov (United States)

Xiao, Fang; Ma, Liang; Zhao, Min; Huang, Guocai; Mirenda, Vincenzo; Dorling, Anthony

2014-01-01

Type 1 diabetes mellitus (T1DM) is an autoimmune disease caused by immune-mediated destruction of insulin-secreting β cells of the pancreas. Near complete dependence on exogenous insulin makes T1DM very difficult to control, with the result that patients are exposed to high blood glucose and risk of diabetic complications and/or intermittent low blood glucose that can cause unconsciousness, fits and even death. Allograft transplantation of pancreatic islets restores normoglycemia with a low risk of surgical complications. However, although successful immediately after transplantation, islets are progressively lost, with most of the patients requiring exogenous insulin within 2 years post-transplant. Therefore, there is an urgent requirement for the development of new strategies to prevent islet rejection. In this study, we explored the importance of human regulatory T cells in the control of islets allograft rejection. We developed a pre-clinical model of human islet transplantation by reconstituting NOD-scid IL2rγnull mice with cord blood-derived human CD34+ stem cells and demonstrated that although the engrafted human immune system mediated the rejection of human islets, their survival was significantly prolonged following adoptive transfer of ex vivo expanded human Tregs. Mechanistically, Tregs inhibited the infiltration of innate immune cells and CD4+ T cells into the graft by down-regulating the islet graft-derived monocyte chemoattractant protein-1. Our findings might contribute to the development of clinical strategies for Treg therapy to control human islet rejection. We also show for the first time that CD34+ cells-reconstituted NOD-scid IL2rγnull mouse model could be beneficial for investigating human innate immunity in vivo. PMID:24594640

Ex vivo expanded human regulatory T cells delay islet allograft rejection via inhibiting islet-derived monocyte chemoattractant protein-1 production in CD34+ stem cells-reconstituted NOD-scid IL2rγnull mice.

Directory of Open Access Journals (Sweden)

Fang Xiao

Full Text Available Type 1 diabetes mellitus (T1DM is an autoimmune disease caused by immune-mediated destruction of insulin-secreting β cells of the pancreas. Near complete dependence on exogenous insulin makes T1DM very difficult to control, with the result that patients are exposed to high blood glucose and risk of diabetic complications and/or intermittent low blood glucose that can cause unconsciousness, fits and even death. Allograft transplantation of pancreatic islets restores normoglycemia with a low risk of surgical complications. However, although successful immediately after transplantation, islets are progressively lost, with most of the patients requiring exogenous insulin within 2 years post-transplant. Therefore, there is an urgent requirement for the development of new strategies to prevent islet rejection. In this study, we explored the importance of human regulatory T cells in the control of islets allograft rejection. We developed a pre-clinical model of human islet transplantation by reconstituting NOD-scid IL2rγnull mice with cord blood-derived human CD34+ stem cells and demonstrated that although the engrafted human immune system mediated the rejection of human islets, their survival was significantly prolonged following adoptive transfer of ex vivo expanded human Tregs. Mechanistically, Tregs inhibited the infiltration of innate immune cells and CD4+ T cells into the graft by down-regulating the islet graft-derived monocyte chemoattractant protein-1. Our findings might contribute to the development of clinical strategies for Treg therapy to control human islet rejection. We also show for the first time that CD34+ cells-reconstituted NOD-scid IL2rγnull mouse model could be beneficial for investigating human innate immunity in vivo.

The influence of combined treatment of Cd, and γ-irradiation on DNA damage and repair in lymphoid tissues of mice

International Nuclear Information System (INIS)

Privezentsev, K.V.; Sirota, N.P.; Gaziev, A.I.

1996-01-01

The effect of combined treatment of Cd and γ-irradiation on DNA damage and repair was studied in lymphoid tissues of mice using single-cell gel assay. Single i.p. injection of CdCl 2 (1 mg Cd/kg body wt), 2 h prior to irradiation resulted in increasing of DNA lesions in peripheral blood lymphocytes (PBL) when compared to non-injected animals. However, the same treatment, 48 h prior to irradiation is shown to decrease DNA damage in PBL and splenocytes in comparison with untreated mice. In thymocytes maximal protective effect of Cd was determined when mice were irradiated in 24 h after injection. The protective effect observed is due to decreasing of initial level of DNA damage in thymocytes as well as acceleration of DNA repair in PBL and splenocytes. 28 refs.; 2 figs

Does a PBL-based medical curriculum predispose training in specific career paths? A systematic review of the literature.

Science.gov (United States)

Tsigarides, Jordan; Wingfield, Laura R; Kulendran, Myutan

2017-01-07

North American medical schools have used problem-based learning (PBL) structured medical education for more than 60 years. However, it has only recently been introduced in other medical schools outside of North America. Since its inception, there has been the debate on whether the PBL learning process predisposes students to select certain career paths. To review available evidence to determine the predisposition of specific career paths when undertaking a PBL-based medical curriculum. The career path trajectory was determined as measured by official Matching Programs, self-reported questionnaires and surveys, and formally defined career development milestones. A systematic literature review was performed. PubMed, Medline, Cochrane and ERIC databases were analysed in addition to reference lists for appropriate inclusion. Eleven studies fitting the inclusion criteria were identified. The majority of studies showed that PBL did not predispose a student to a career in a specific speciality (n = 7 out of 11 studies, 64%). However, three studies reported a significantly increased number of PBL graduates working in primary care compared to those from a non-PBL curriculum. PBL has been shown not to predispose medical students to a career in General Practice or any other speciality. Furthermore, a greater number of similar studies are required before a definitive conclusion can be made in the future.

Problem-based Learning (PBL in Sociolinguistics as a Way of Encouraging Active Learning

Directory of Open Access Journals (Sweden)

Engku Ibrahim Engku Haliza

2018-01-01

Full Text Available The major concern of this paper is to advocate the integration of PBL strategies in classroom instruction as a way of promoting active learning. It is undoubted that the benefits of problem-based learning (PBL are numerous. In the sciences, PBL has been well integrated in the curriculum. This research reports of an experience of integrating problem-based learning in an introductory Sociolinguistics course for 60 undergraduates of a Bachelors of English programme through a semester that ran for 14 weeks. A focused group interview and questionnaire were used to find out the perceptions of the students undergoing the hybrid PBL course. The findings of this study reveal that students generally enjoyed the PBL approach and found that they had little choice but to become active learners. Some challenges faced by the learners were also highlighted. These findings have implications for the integration of PBL in the field of social sciences.

Antiproliferative effects of TRPV1 ligands on nonspecific and enteroantigen-specific T cells from wild-type and Trpv1 KO mice

DEFF Research Database (Denmark)

Belmaáti, Mohammed-Samir; Diemer, Sanne; Hvarness, Tine

2014-01-01

BACKGROUND: Treatment with the TRPV1 agonist, capsaicin, was previously shown to protect against experimental colitis in the severe combined immunodeficiency (SCID) T-cell transfer model. Here, we investigate trpv1 gene expression in lymphoid organs and cells from SCID and BALB/c mice to identify...

Cytoplasmic Hu-Antigen R (HuR) Expression is Associated with Poor Survival in Patients with Surgically Resected Cholangiocarcinoma Treated with Adjuvant Gemcitabine-Based Chemotherapy.

Science.gov (United States)

Toyota, Kazuhiro; Murakami, Yoshiaki; Kondo, Naru; Uemura, Kenichiro; Nakagawa, Naoya; Takahashi, Shinya; Sueda, Taijiro

2018-05-01

Hu-antigen R (HuR) is an RNA-binding protein that regulates the stability, translation, and nucleus-to-cytoplasm translocation of messenger RNAs (mRNAs). The aim of this study was to investigate the prognostic significance of HuR in cholangiocarcinoma patients who received adjuvant gemcitabine-based chemotherapy (AGC) after surgical resection. Nuclear and cytoplasmic HuR expression was investigated immunohistochemically in 131 patients with resected cholangiocarcinoma, including 91 patients administered AGC and 40 patients who did not receive adjuvant chemotherapy. The correlation between HuR expression and survival was evaluated by statistical analysis. High nuclear and cytoplasmic HuR expression was observed in 67 (51%) and 45 (34%) patients, respectively. Cytoplasmic HuR expression was significantly associated with lymph node metastasis (p < 0.01), while high cytoplasmic HuR expression was significantly associated with poor disease-free survival [DFS] (p = 0.03) and overall survival [OS] (p = 0.001) in the 91 patients who received AGC, but not in the 40 patients who did not receive AGC (DFS p = 0.17; OS p = 0.07). In the multivariate analysis of patients who received AGC, high cytoplasmic HuR expression was an independent predictor of poor DFS (hazard ratio [HR] 1.77; p = 0.04) and OS (HR 2.09; p = 0.02). Nuclear HuR expression did not affect the survival of enrolled patients. High cytoplasmic HuR expression was closely associated with the efficacy of AGC in patients with cholangiocarcinoma. The current findings warrant further investigations to optimize adjuvant chemotherapy regimens for resectable cholangiocarcinoma.

Developing intercultural competencies in a PBL environment

DEFF Research Database (Denmark)

Du, Xiangyun; Hansen, Carsten Jahn

2006-01-01

This paper discusses the influences of international programs in a problem based, project and group work organized learning (PBL) environment on the development of intercultural competencies. Based on the discussion of the positive effects as well as the observed barriers in the educational...... practice of international programs, this paper suggests that PBL can be a good example of a supportive learning environment in terms of providing students opportunities to develop intercultural competences. However, in order to make the best of international programs as an intercultural learning context...... students from different cultures can learn from each other and develop intercultural competencies together....

Loyalty, Harm and Duty: PBL in a Media Ethics Course.

Science.gov (United States)

Slattery, Karen L.

2002-01-01

Considers how to teach the various areas of mass media in sufficient depth, without sacrificing breadth. Discusses a variation of problem-based learning (PBL) as one possible solution to that educational conundrum. Focuses on a project developed by a group of public relations students using the PBL method. (SG)

Targeting Mycobacterium tuberculosis nucleoid-associated protein HU with structure-based inhibitors

Science.gov (United States)

Bhowmick, Tuhin; Ghosh, Soumitra; Dixit, Karuna; Ganesan, Varsha; Ramagopal, Udupi A.; Dey, Debayan; Sarma, Siddhartha P.; Ramakumar, Suryanarayanarao; Nagaraja, Valakunja

2014-06-01

The nucleoid-associated protein HU plays an important role in maintenance of chromosomal architecture and in global regulation of DNA transactions in bacteria. Although HU is essential for growth in Mycobacterium tuberculosis (Mtb), there have been no reported attempts to perturb HU function with small molecules. Here we report the crystal structure of the N-terminal domain of HU from Mtb. We identify a core region within the HU-DNA interface that can be targeted using stilbene derivatives. These small molecules specifically inhibit HU-DNA binding, disrupt nucleoid architecture and reduce Mtb growth. The stilbene inhibitors induce gene expression changes in Mtb that resemble those induced by HU deficiency. Our results indicate that HU is a potential target for the development of therapies against tuberculosis.

The Effect of Model Problem Based Learning (Pbl)

OpenAIRE

Safrina, Safrina; Saminan, Saminan

2015-01-01

This study aims to determine the effect of the application of PBL models of science process skills (PPP) and the understanding of the concept of chemical substances in food at eighth grade students MTsN Meureudu. This study is a descriptive study using the research design one group pretest and posttest design. Samples were 19 eighth grade students MTsN Meureudu school year 2013/2014. Data collected by pretest and posttest to determine the effect of the application of PBL models and observatio...

PBL 教学模式在眼科教学中应用的探讨与实践%Probe and Practice into the Tuition of Ophthalmology in a PBL Curriculum

Institute of Scientific and Technical Information of China (English)

邓禹

2014-01-01

The curriculum of problem-based learning (PBL)trended to be the new model of medical education.The superior-ities of PBL were evaluated and compared with lecture-based learning (LBL).Introducing PBL into ophthalmology could im-prove educational quality and effectiveness.%PBL 教学法（problem-based learning）即“以问题为基础的讨论式学习”逐渐成为我国医学教育模式改革的趋势。在传统的LBL 教学方法（lecture-based learning）基础上，眼科教学中引入PBL 教学法，提高教学质量。

Different modes of interaction by TIAR and HuR with target RNA and DNA.

Science.gov (United States)

Kim, Henry S; Wilce, Matthew C J; Yoga, Yano M K; Pendini, Nicole R; Gunzburg, Menachem J; Cowieson, Nathan P; Wilson, Gerald M; Williams, Bryan R G; Gorospe, Myriam; Wilce, Jacqueline A

2011-02-01

TIAR and HuR are mRNA-binding proteins that play important roles in the regulation of translation. They both possess three RNA recognition motifs (RRMs) and bind to AU-rich elements (AREs), with seemingly overlapping specificity. Here we show using SPR that TIAR and HuR bind to both U-rich and AU-rich RNA in the nanomolar range, with higher overall affinity for U-rich RNA. However, the higher affinity for U-rich sequences is mainly due to faster association with U-rich RNA, which we propose is a reflection of the higher probability of association. Differences between TIAR and HuR are observed in their modes of binding to RNA. TIAR is able to bind deoxy-oligonucleotides with nanomolar affinity, whereas HuR affinity is reduced to a micromolar level. Studies with U-rich DNA reveal that TIAR binding depends less on the 2'-hydroxyl group of RNA than HuR binding. Finally we show that SAXS data, recorded for the first two domains of TIAR in complex with RNA, are more consistent with a flexible, elongated shape and not the compact shape that the first two domains of Hu proteins adopt upon binding to RNA. We thus propose that these triple-RRM proteins, which compete for the same binding sites in cells, interact with their targets in fundamentally different ways.

PBL, Hands-On/ Digital resources in Geology, (Teaching/ Learning)

Science.gov (United States)

Soares, Rosa; Santos, Cátia; Carvalho, Sara

2015-04-01

The present study reports the elaboration, application and evaluation of a problem-based learning (PBL) program that aims to evaluate the effectiveness in students learning the Rock Cycle theme. Prior research on both PBL and Rock Cycle was conducted within the context of science education so as to elaborate and construct the intervention program. Findings from these studies indicated both the PBL methodology and Rock Cycle as helpful for teachers and students. PBL methodology has been adopted in this study since it is logically incorporated in a constructivism philosophy application and it was expected that this approach would assist students towards achieving a specific set of competencies. PBL is a student-centered method based on the principle of using problems as the starting point for the acquisition of new knowledge. Problems are based on complex real-world situations. All information needed to solve the problem is initially not given. Students will identify, find, and use appropriate resources to complete the exercise. They work permanently in small groups, developing self-directed activities and increasing participation in discussions. Teacher based guidance allows students to be fully engaged in knowledge building. That way, the learning process is active, integrated, cumulative, and connected. Theme "Rock Cycle" was introduced using a problematic situation, which outlined the geological processes highlighted in "Foz do Douro" the next coastline of the school where the study was developed. The questions proposed by the students were solved, using strategies that involved the use of hands-on activities and virtual labs in Geology. The systematization of the selected theme was performed in a field excursion, implemented according to the organizational model of Nir Orion, to The "Foz do Douro" metamorphic complex. In the evaluation of the learning process, data were obtained on students' development of knowledge and competencies through the application of

Radioimmunodetection of human leukemia with anti-interleukin-2 receptor antibody in severe combined immunodeficiency mice

International Nuclear Information System (INIS)

Hosono, Makoto; Takaori-Kondo, Akifumi; Zheng-Sheng, Yao; Kobayashi, Hisataka; Hosono, Masako N.; Sakahara, Harumi; Imada, Kazunori; Okuma, Minoru; Uchiyama, Takashi; Konishi, Junji

1995-01-01

Anti-Tac monoclonal antibody recognizes human interleukin-2 receptor, which is overexpressed in leukemic cells of most adult T-cell leukemia (ATL) patients. To examine the potency of anti-Tac for targeting of ATL, biodistributions of intravenously administered 125 I- and 111 In-labeled anti-Tac were examined in severe combined immunodeficiency (SCID) mice inoculated with ATL cells. Significant amounts of radiolabeled anti-Tac were found in the spleen and thymus. The trafficking of ATL cells in SCID mice was detected using 111 In-oxine-labeled ATL cells. These results were coincident with the histologically confirmed infiltration of ATL cells. The radiolabeled anti-Tac seemed potent for targeting of ATL

Application of Problem Based Learning ((PBL) in a Course on Financial Accounting Principles

Science.gov (United States)

Manaf, Nor Aziah Abdul; Ishak, Zuaini; Hussin, Wan Nordin Wan

2011-01-01

Purpose: This paper aims to share experiences in teaching a Financial Accounting Principles course using a hybrid problem based learning (PBL) method. The three specific objectives of this paper are to document how the PBL project for this course was developed and managed in class, to compare the academic performance of PBL students with non-PBL…

Integrating Creativity Training into Problem and Project-Based Learning (PBL) Curriculum in Engineering Education

DEFF Research Database (Denmark)

Zhou, Chunfang

2012-01-01

In order to foster creative engineers, a creativity training programme was carried out in medialogy education in a Problem and Project-Based Learning (PBL) environment at Aalborg University, Denmark. This paper focuses on the question of how engineering students perceive the strategy of integrating...... creativity training into a PBL curriculum. A total of 20 medialogy students in the training programme were interviewed. The data shows that the training programme was thought useful and students get benefits such as gaining project work skills, creative concepts and confidence of being creative. However...

Status of medical education reform at Saga Medical School 5 years after introducing PBL.

Science.gov (United States)

Oda, Yasutomo; Koizumi, Shunzo

2008-03-01

In Japan, problem-based learning (PBL) is a relatively new method of educating medical students that is reforming the face of medical education throughout the world, including Asia. It shifts from teacher-centered learning strategies (for example, lectures in large auditoriums) to student-centered, self-directed learning methods (for example, active discussions and problem-solving by students in small groups under the guidance of faculty tutors). Upon a recommendation by the Japan Model Core Curriculum, Saga Medical School introduced a PBL curriculum 5 years ago. A full PBL curriculum was adopted from the McMaster model through Hawaii. A description of how PBL was implemented into the 3rd and 4th year (Phase III curriculum) is given. The overall result has been good. Students who experienced PBL had increased scores on the National Medical License Exam, and Saga increased its ranking from 56th to 19th of the 80 medical schools in Japan. A key step was introduction of the educational scaffolding in PBL Step 0. Students were allowed to see page one of the PBL case, containing the chief complaint, on the weekend before meeting in small groups. Despite a perceived overall benefit to student learning, symptoms of superficial discussions by students have been observed recently. How this may be caused by poor case design is discussed. Other problems, including "silent tutors" and increased faculty workload, are discussed. It is concluded that after 5 years, Saga's implementation of a PBL curriculum has been successful. However, many additional issues, including motivation of students and preparation for PBL in the first 2 years, must still be resolved in the future. This is the first description of the positive and negative outcomes associated with the reform of medical education and the introduction of PBL to a traditional medical school curriculum in Japan.

Status of Medical Education Reform at Saga Medical School 5 Years After Introducing PBL

Directory of Open Access Journals (Sweden)

Yasutomo Oda

2008-03-01

Full Text Available In Japan, problem-based learning (PBL is a relatively new method of educating medical students that is reforming the face of medical education throughout the world, including Asia. It shifts from teacher-centered learning strategies (for example, lectures in large auditoriums to student-centered, self-directed learning methods (for example, active discussions and problem-solving by students in small groups under the guidance of faculty tutors. Upon a recommendation by the Japan Model Core Curriculum, Saga Medical School introduced a PBL curriculum 5 years ago. A full PBL curriculum was adopted from the McMaster model through Hawaii. A description of how PBL was implemented into the 3rd and 4th year (Phase III curriculum is given. The overall result has been good. Students who experienced PBL had increased scores on the National Medical License Exam, and Saga increased its ranking from 56th to 19th of the 80 medical schools in Japan. A key step was introduction of the educational scaffolding in PBL Step 0. Students were allowed to see page one of the PBL case, containing the chief complaint, on the weekend before meeting in small groups. Despite a perceived overall benefit to student learning, symptoms of superficial discussions by students have been observed recently. How this may be caused by poor case design is discussed. Other problems, including “silent tutors” and increased faculty workload, are discussed. It is concluded that after 5 years, Saga's implementation of a PBL curriculum has been successful. However, many additional issues, including motivation of students and preparation for PBL in the first 2 years, must still be resolved in the future. This is the first description of the positive and negative outcomes associated with the reform of medical education and the introduction of PBL to a traditional medical school curriculum in Japan.

If PBL is the answer, then what is the problem?

DEFF Research Database (Denmark)

Huttel, Hans; Gnaur, Dorina

of project work in the undergraduate degree programme in computer science at Aalborg University. Danish PBL-based higher education institutions espouse the qualities of problembased projects but actual practice shows a different picture. The predominant use of project catalogues and the formal requirements......This paper identifies and analyzes problems with routinization of project work in PBL-based degree programmes and points towards possible solutions. The paper uses a survey of students’ and supervisor’s perceptions of project work in the context of attempts to emphasize problem-based aspects...... imposed by accreditation inhibit central intentions behind problem-based project work. The study reported on is limited to a specific degree programme and to a particular approach to dealing with the problem of routinization. The findings in this paper point towards the need for action research into new...

Virulent variants emerging in mice infected with the apathogenic prototype strain of the parvovirus minute virus of mice exhibit a capsid with low avidity for a primary receptor.

Science.gov (United States)

Rubio, Mari-Paz; López-Bueno, Alberto; Almendral, José M

2005-09-01

The mechanisms involved in the emergence of virulent mammalian viruses were investigated in the adult immunodeficient SCID mouse infected by the attenuated prototype strain of the parvovirus Minute Virus of Mice (MVMp). Cloned MVMp intravenously inoculated in mice consistently evolved during weeks of subclinical infection to variants showing altered plaque phenotypes. All the isolated large-plaque variants spread systemically from the oronasal cavity and replicated in major organs (brain, kidney, liver), in sharp contrast to the absolute inability of the MVMp and small-plaque variants to productively invade SCID organs by this natural route of infection. The virulent variants retained the MVMp capacity to infect mouse fibroblasts, consistent with the lack of genetic changes across the 220-to-335 amino acid sequence of VP2, a capsid domain containing main determinants of MVM tropism. However, the capsid of the virulent variants shared a lower affinity than the wild type for a primary receptor used in the cytotoxic infection. The capsid gene of a virulent variant engineered in the MVMp background endowed the recombinant virus with a large-plaque phenotype, lower affinity for the receptor, and productive invasiveness by the oronasal route in SCID mice, eventually leading to 100% mortality. In the analysis of virulence in mice, both MVMp and the recombinant virus similarly gained the bloodstream 1 to 2 days postoronasal inoculation and remained infectious when adsorbed to blood cells in vitro. However, the wild-type MVMp was cleared from circulation a few days afterwards, in contrast to the viremia of the recombinant virus, which was sustained for life. Significantly, attachment to an abundant receptor of primary mouse kidney epithelial cells by both viruses could be quantitatively competed by wild-type MVMp capsids, indicating that virulence is not due to an extended receptor usage in target tissues. We conclude that the selection of capsid-receptor interactions of

PBL in a multicultural environment

DEFF Research Database (Denmark)

Hansen, Carsten Jahn; Du, Xiangyun

2006-01-01

, Aalborg University has developed its own version of PBL, based in project work organised in groups of students. The result is a focus on the development of student abilities and competences related to discipline knowledge as well as to cooperation, communication, management and self-reflection. So far...

Mice lacking neuropeptide Y show increased sensitivity to cocaine

DEFF Research Database (Denmark)

Sørensen, Gunnar; Woldbye, David Paul Drucker

2012-01-01

There is increasing data implicating neuropeptide Y (NPY) in the neurobiology of addiction. This study explored the possible role of NPY in cocaine-induced behavior using NPY knockout mice. The transgenic mice showed a hypersensitive response to cocaine in three animal models of cocaine addiction...

Global network on engineering education research and expertise in PBL

DEFF Research Database (Denmark)

Enemark, Stig; Kolmos, Anette; Moesby, Egon

2006-01-01

in order to facilitate better access to and co-operation within the PBL area. One of the absolute important tasks for UCPBL is to provide evidence for the effectiveness of PBL worldwide. Thus, there is a special attempt to establish links between engineering education researchers in this field....... This involves considerations concerning what is engineering education research – and how do we promote research based staff and educational development.......The UCPBL Centre for Problem Based Learning is based at Aalborg University, Denmark, known world-wide for its successful educational approach based on problem oriented project work. Due to more than 30 years of experience in utilizing PBL-learning principles in Engineering Education, an increasing...

Application of HSVtk suicide gene to X-SCID gene therapy: Ganciclovir treatment offsets gene corrected X-SCID B cells

International Nuclear Information System (INIS)

Uchiyama, Toru; Kumaki, Satoru; Ishikawa, Yoshinori; Onodera, Masafumi; Sato, Miki; Du, Wei; Sasahara, Yoji; Tanaka, Nobuyuki; Sugamura, Kazuo; Tsuchiya, Shigeru

2006-01-01

Recently, a serious adverse effect of uncontrolled clonal T cell proliferation due to insertional mutagenesis of retroviral vector was reported in X-SCID gene therapy clinical trial. To offset the side effect, we have incorporated a suicide gene into therapeutic retroviral vector for selective elimination of transduced cells. In this study, B-cell lines from two X-SCID patients were transduced with bicistronic retroviral vector carrying human γc chain cDNA and Herpes simplex virus thymidine kinase gene. After confirmation of functional reconstitution of the γc chain, the cells were treated with ganciclovir (GCV). The γc chain positive cells were eliminated under low concentration without cytotoxicity on untransduced cells and have not reappeared at least for 5 months. Furthermore, the γc chain transduced cells were still sensitive to GCV after five months. These results demonstrated the efficacy of the suicide gene therapy although further in vivo studies are required to assess feasibility of this approach in clinical trial

Dental students' evaluation of 2 community-oriented PBL modules.

Science.gov (United States)

Pau, A K; Collinson, S; Croucher, R

1999-11-01

To evaluate dental students' perception of 2 problem-based learning (PBL) modules in Dental Public Health implemented within the context of a traditional formal curriculum. 2 dental community modules were implemented with an 8-month interval between them on the same group of dental undergraduates; the first in Term 2 and the second in Term 4 of a 5-year 15-term dental course. At the end of each module, a semi-structured questionnaire was administered to evaluate the introductory lecture, the fieldwork activity and the organisation of the modules. In both modules, students reported gaining insight into the subject matter, skills in teamwork, making presentations and collecting data. Some students in the 1st module needed more time to fulfil their learning objectives and had difficulty in collecting data. In the 2nd module, students reported that they lacked motivation because of the place of the module within their timetable. Opinions differed about groupwork. The content of and interest generated by fieldwork activity was rated more positively in the 2nd module than the 1st. Less positively rated in the 2nd module was the introductory lecture and module organisation. Implementing PBL within a traditional curriculum does not offer uniform outcomes for students. Optimum group size and adequate time are necessary if students are to benefit from PBL. A consistent and continuous PBL approach should be adopted rather than a sporadic one. Further research should establish the optimum balance between PBL and traditional approaches that would allow students to maximise the benefits of both and to identify those students best equipped to benefit from a 'mixed economy' of learning.

Simultaneous Administration of ADSCs-Based Therapy and Gene Therapy Using Ad-huPA Reduces Experimental Liver Fibrosis.

Science.gov (United States)

Meza-Ríos, Alejandra; García-Benavides, Leonel; García-Bañuelos, Jesus; Salazar-Montes, Adriana; Armendáriz-Borunda, Juan; Sandoval-Rodríguez, Ana

2016-01-01

hADSCs transplantation in cirrhosis models improves liver function and reduces fibrosis. In addition, Ad-huPA gene therapy diminished fibrosis and increased hepatocyte regeneration. In this study, we evaluate the combination of these therapies in an advanced liver fibrosis experimental model. hADSCs were expanded and characterized before transplantation. Ad-huPA was simultaneously administrated via the ileac vein. Animals were immunosuppressed by CsA 24 h before treatment and until sacrifice at 10 days post-treatment. huPA liver expression and hADSCs biodistribution were evaluated, as well as the percentage of fibrotic tissue, hepatic mRNA levels of Col-αI, TGF-β1, CTGF, α-SMA, PAI-I, MMP2 and serum levels of ALT, AST and albumin. hADSCs homed mainly in liver, whereas huPA expression was similar in Ad-huPA and hADSCs/Ad-huPA groups. hADSCs, Ad-huPA and hADSCs/Ad-huPA treatment improves albumin levels, reduces liver fibrosis and diminishes Collagen α1, CTGF and α-SMA mRNA liver levels. ALT and AST serum levels showed a significant decrease exclusively in the hADSCs group. These results showed that combinatorial effect of cell and gene-therapy does not improve the antifibrogenic effects of individual treatments, whereas hADSCs transplantation seems to reduce liver fibrosis in a greater proportion.

Cooperative Problem-Based Learning (CPBL: A Practical PBL Model for a Typical Course

Directory of Open Access Journals (Sweden)

Khairiyah Mohd-Yusof

2011-09-01

Full Text Available Problem-Based Learning (PBL is an inductive learning approach that uses a realistic problem as the starting point of learning. Unlike in medical education, which is more easily adaptable to PBL, implementing PBL in engineering courses in the traditional semester system set-up is challenging. While PBL is normally implemented in small groups of up to ten students with a dedicated tutor during PBL sessions in medical education, this is not plausible in engineering education because of the high enrolment and large class sizes. In a typical course, implementation of PBL consisting of students in small groups in medium to large classes is more practical. However, this type of implementation is more difficult to monitor, and thus requires good support and guidance in ensuring commitment and accountability of each student towards learning in his/her group. To provide the required support, Cooperative Learning (CL is identified to have the much needed elements to develop the small student groups to functional learning teams. Combining both CL and PBL results in a Cooperative Problem-Based Learning (CPBL model that provides a step by step guide for students to go through the PBL cycle in their teams, according to CL principles. Suitable for implementation in medium to large classes (approximately 40-60 students for one floating facilitator, with small groups consisting of 3-5 students, the CPBL model is designed to develop the students in the whole class into a learning community. This paper provides a detailed description of the CPBL model. A sample implementation in a third year Chemical Engineering course, Process Control and Dynamics, is also described.

Problem based learning (PBL) vs. Case based curriculum in clinical clerkship, Internal Medicine innovated Curriculum, Student prospective.

Science.gov (United States)

Aljarallah, Badr; Hassan, Mohammad Saleh

2015-04-01

The vast majority of PBL experience is in basic science courses. Application of classic Problem based learning in clerkship phase is challenging. Although the clinical case is considered a problem, yet solving this problem following the burrow's law has faced hurdles. The difficulties are facing the learner, the teacher and curricula. We implement innovative curriculum for the clerkship year in internal medicine course. We surveyed the student just before coming to an internal medicine course to ask them about continuing PBL or other types of learning in clinical years. A committee was created to study the possible ways to integrate PBL in the course. After multiple brainstorming meeting, an innovated curriculum was implemented. Student surveyed again after they completed their course. The survey is asking them about what is the effect of the implemented curriculum in their skills, attitude, and knowledge. 70% of Students, who finished their basic science in PBL, preferred not to have classical PBL, but more a clinical oriented case based curriculum in the clinical years. After this innovated curriculum, 50-60 % of students who completed it showed a positive response in all aspects of effects including skill, attitude, and knowledge. The Innovated curriculum includes daily morning report, 3 bedside teaching, investigation session, and clinical reasoning weekly, and Lectures up to twice a week. We suggest implementing a curriculum with PBL and case-based criteria in clinical phase are feasible, we are providing a framework with this innovated curriculum.

Barrows' Integration of Cognitive and Clinical Psychology in PBL Tutor Guidelines

Science.gov (United States)

McCaughan, Kareen

2013-01-01

Scholars have noted PBL is consistent with John Dewey's educational theories and with constructivist philosophies. This paper explores the similarities between the assumptions within Howard Barrows' principles for the PBL tutor's actions with Dewey's theories that address teacher behaviors and with Carl Rogers's conceptual frameworks that support…

PBL and critical thinking disposition in Chinese medical students – A randomized cross-sectional stu

Directory of Open Access Journals (Sweden)

XiangYun Du

2013-07-01

Full Text Available The purpose of this study was to explore the relationship of problem-based learning (PBL and the development of critical thinking disposition (CT and academic achievement in Chinese medical students using a cross-sectional randomized design. Medical students from China Medical University (CMU were randomized to PBL or non-PBL teaching at the commencement of the study. After five years of study, CT was scored by a Chinese version of the California Critical Thinking Disposition Inventory (CCTDI-CV. The score achieved on a Computer Case Simulation (CCS test evaluated academic performance. Total CT score was higher in PBL students (n=170 than non-PBL students (n=83 (304.7±36.8 vs. 279.2±39.4, p < 0.01. Subscale CT-scores were significant in favor of PBL in six of the seven subscales (truth seeking, open-mindedness, analyticity, systematicity, inquisitiveness, maturity. There was no significant difference in terms of gender on the total CT score, though minor differences were seen in subscales favoring female PBL students. PBL students had higher CCS scores than non-PBL students, but not significantly (112.8±20.6 vs. 107.3±16.5; p=0.11. There was no significant correlation between CCS scores and CCTDI-CV results. Male students scored slightly higher on the CCS test compared to female students (male 113.4±18.9 vs. female 109.7±19.7, but the difference was not significant. This study concludes that in Chinese medical students, PBL teaching was related to a higher disposition of critical thinking, but not to improved academic skills.

Infecciones en huéspedes inmunocomprometidos

OpenAIRE

Cuéllar Ponce de León, Luis Ernesto

2013-01-01

Las infecciones son causa frecuente de morbimortalidad en huéspedes inmunocomprometidos. La frecuencia y diversidad de infecciones en esta población dependerá del tipo de inmunocompromiso, tratamiento recibido y aspecto epidemiológico. Los huéspedes con neutropenia desarrollan infecciones por bacterias extracelulares no encapsuladas y hongos levaduriformes y filamentosos; el diagnóstico precoz y tratamiento oportuno de las mismas son considerados una emergencia por su severidad y gran mortali...

The Design and Program Evaluation of a Distributed PBL Curriculum for Training Family Doctors in Brazil

Science.gov (United States)

Tomaz, Jose B. C.; van der Molen, Henk T.; Mamede, Silvia

2013-01-01

Over the past decade Problem-based Learning (PBL) and distance education have been combined as educational approaches in higher education. This combination has been called distributed PBL (dPBL). However, more research is needed to obtain more evidence and deeper insight in how to design and implement dPBL. The present study aims at describing the…

PBL-GIS in Secondary Geography Education: Does It Result in Higher-Order Learning Outcomes?

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Liu, Yan; Bui, Elisabeth N.; Chang, Chew-Hung; Lossman, Hans G.

2010-01-01

This article presents research on evaluating problem-based learning using GIS technology in a Singapore secondary school. A quasi-experimental research design was carried to test the PBL pedagogy (PBL-GIS) with an experimental group of students and compare their learning outcomes with a control group who were exposed to PBL but not GIS. The…

Lack of spontaneous and radiation-induced chromosome breakage at interstitial telomeric sites in murine scid cells.

Science.gov (United States)

Wong, H-P; Mozdarani, H; Finnegan, C; McIlrath, J; Bryant, P E; Slijepcevic, P

2004-01-01

Interstitial telomeric sites (ITSs) in chromosomes from DNA repair-proficient mammalian cells are sensitive to both spontaneous and radiation-induced chromosome breakage. Exact mechanisms of this chromosome breakage sensitivity are not known. To investigate factors that predispose ITSs to chromosome breakage we used murine scid cells. These cells lack functional DNA-PKcs, an enzyme involved in the repair of DNA double-strand breaks. Interestingly, our results revealed lack of both spontaneous and radiation-induced chromosome breakage at ITSs found in scid chromosomes. Therefore, it is possible that increased sensitivity of ITSs to chromosome breakage is associated with the functional DNA double-strand break repair machinery. To investigate if this is the case we used scid cells in which DNA-PKcs deficiency was corrected. Our results revealed complete disappearance of ITSs in scid cells with functional DNA-PKcs, presumably through chromosome breakage at ITSs, but their unchanged frequency in positive and negative control cells. Therefore, our results indicate that the functional DNA double-strand break machinery is required for elevated sensitivity of ITSs to chromosome breakage. Interestingly, we observed significant differences in mitotic chromosome condensation between scid cells and their counterparts with restored DNA-PKcs activity suggesting that lack of functional DNA-PKcs may cause a defect in chromatin organization. Increased condensation of mitotic chromosomes in the scid background was also confirmed in vivo. Therefore, our results indicate a previously unanticipated role of DNA-PKcs in chromatin organisation, which could contribute to the lack of ITS sensitivity to chromosome breakage in murine scid cells. Copyright 2003 S. Karger AG, Basel

Dexamethasone/1alpha-25-dihydroxyvitamin D3-treated dendritic cells suppress colitis in the SCID T-cell transfer model

DEFF Research Database (Denmark)

Pedersen, Anders Elm; Schmidt, Esben Gjerløff Wedebye; Gad, Monika

2008-01-01

severe combined immunodeficient (SCID) mice adoptively transferred with CD4(+) CD25(-) T cells from the development of wasting disease and colitis. We therefore established an in vitro test that could predict the in vivo function of DCs and improve strategies for the preparation of immunomodulatory DCs...... in this model. Based on these in vitro findings, we here evaluate three methods for DC generation including short-term and long-term IL-10 exposure or DC exposure to dexamethasone in combination with vitamin D3 (Dex/D3). All DCs resulted in lower CD4(+) CD25(-) T-cell enteroantigen-specific responses in vitro...

Introducing Process Competences in a PBL-based Engineering Course

DEFF Research Database (Denmark)

Soler, José; Andersson, Pernille Hammar

2013-01-01

The article describes an experiment in which elements related to generic professional competences, such as group work methodology, project planning, task delegation and communication, have been introduced in an existing course, tailored as a Problem Base Learning (PBL) course in Advanced Telecomm......The article describes an experiment in which elements related to generic professional competences, such as group work methodology, project planning, task delegation and communication, have been introduced in an existing course, tailored as a Problem Base Learning (PBL) course in Advanced...

Middle School Engineering Problem Solving Using Traditional vs. e-PBL Module Instruction

Science.gov (United States)

Baele, Loren C.

This multiple methods (Denzin, 1978) study investigated two instructional approaches, traditional module and electronic Problem-Based Learning instruction (e-PBL), used within a middle school engineering classroom focused on the variables of engagement, content knowledge, student self-assessment and teacher assessment of problem solving solutions. A non-equivalent group quasi-experimental research design (Creswell, 2015) was used on middle school students (N = 100) between those that received traditional module instruction (n = 51) and e-PBL instruction (n = 49). The qualitative approach of triangulation (Jick, 1979) was used to identify emergent themes for both between and within methods of data analysis on student engagement survey responses, two days of field observations notes, and six student interview transcripts. The quantitative results identified that students who received e-PBL instruction self-reported significantly greater engagement than those who received traditional module instruction. Further, there was a significant interaction effect between engineering content knowledge by group and gender as males who received e-PBL instruction had greater growth of content knowledge scores than males receiving traditional instruction, while females who received traditional instruction had greater growth of content knowledge scores than females in the e-PBL group. Through triangulation of the qualitative data, the emergent themes of the study suggest that hands-on learning produces higher levels of reported engagement independent of instructional method. The emergence of problem solving fatigue developed when both study groups reported a decline in engagement when entering into the final phase of the quantitative study suggesting that too many complex, ill-structured problems in rapid succession may negatively impact student engagement. Although females within the treatment group were most engaged, they did not achieve the knowledge growth of the females in the

PBL in Teacher Education: Its Effects on Achievement and Self-Regulation

Science.gov (United States)

Erdogan, Tolga; Senemoglu, Nuray

2017-01-01

Problem-based learning (PBL) as an educational practice continues to have great impact on all levels of education and across different disciplines. The aim of this experimental study is to examine the effects of PBL on prospective teachers' academic achievements and self-regulation. The treatment group (n = 36) and the control group (n = 21)…

Pediatric SCI/D caregiver mental health and family dynamics in Colombia, South America.

Science.gov (United States)

Doyle, Sarah T; Perrin, Paul B; Nicholls, Elizabeth; Olivera, Silvia Leonor; Quintero, Lorena Medina; Otálvaro, Nadezda Yulieth Méndez; Arango-Lasprilla, Juan Carlos

2016-01-01

This study examined the connections between family dynamics and the mental health of caregivers of youth with spinal cord injuries/disorders (SCI/D) caregivers from Colombia, South America. It was hypothesized that lower family functioning would be associated with poorer caregiver mental health. A cross-sectional study of self-report data collected from caregivers through the Hospital Universatario Hernando Moncaleano Perdomo in Neiva, Colombia. Thirty caregivers of children with SCI/D from Nevia, Colombia who were a primary caregiver for ≥3 months, providing care for an individual who was ≥6 months post-injury/diagnosis, familiar with the patient's history, and without neurological or psychiatric conditions. Caregivers' average age was 41.30 years (SD = 10.98), and 90% were female. Caregivers completed Spanish versions of instruments assessing their own mental health and family dynamics. Family dynamics explained 43.2% of the variance in caregiver burden and 50.1% of the variance in satisfaction with life, although family dynamics were not significantly associated with caregiver depression in the overall analysis. Family satisfaction was the only family dynamics variable to yield a significant unique association with any index of caregiver mental health (satisfaction with life). If similar findings emerge in future intervention research, interventions for pediatric SCI/D caregivers in Colombia and other similar global regions could benefit from including techniques to improve family dynamics, especially family satisfaction, given the strong potentially reciprocal connection between these dynamics and caregiver mental health. The degree of disability resulting from SCI/D can vary greatly depending on the severity and level of the lesion, though permanent impairment is often present that profoundly impacts both physical and psychological functioning. Very little is known about the impact of pediatric SCI/D in developing countries, despite the high rates of

[Teaching Bioethics to Students of Medicine with Problem-Based Learning (PBL)].

Science.gov (United States)

Bosch-Barrera, Joaquim; Briceño García, Hugo C; Capella, Dolors; De Castro Vila, Carmen; Farrés, Ramón; Quintanas, Anna; Ramis, Josep; Roca, Rosa; Brunet, Joan

2015-01-01

We present the experience of the introduction of the subject of bioethics in a medical school in order to give to the 73 students of 5th degree skills to handle ethical conflicts in their practice. The main teaching method used was problem-based learning (PBL). Skills objectives are described. The course was structured with a theoretical seminar (2 hours of duration), a workshop (2 hours of duration), 4 cases of PBL (24 hours of duration in total) and a role playing workshop (2 hours of duration). The seminar was aimed at the acquisition of theoretical knowledge. The PBL cases provided critical appraisal, obtaining knowledge, and application. The Role Playing set out for the practical demonstration of skills acquired in a simulated environment. A continuous assessment of students was performed throughout their practice on the PBL cases (40% of the final score) and also a final evaluation of the course was carried out via exam (60% of the final score). Students completed a course and faculty evaluation anonymously, which came out with positive results (median score of 8.5/10).

Teaching process competencies in a PBL curriculum

DEFF Research Database (Denmark)

Kofoed, Lise Busk; Hansen, Søren; Kolmos, Anette

2004-01-01

The article describes the background in teaching students process competencies in a project-organized and problem-based (PBL) educational system at Aalborg University, and presents an analysis of a course development....

HU deviation in lung and bone tissues: Characterization and a corrective strategy.

Science.gov (United States)

Ai, Hua A; Meier, Joseph G; Wendt, Richard E

2018-05-01

In the era of precision medicine, quantitative applications of x-ray Computed Tomography (CT) are on the rise. These require accurate measurement of the CT number, also known as the Hounsfield Unit. In this study, we evaluated the effect of patient attenuation-induced beam hardening of the x-ray spectrum on the accuracy of the HU values and a strategy to correct for the resulting deviations in the measured HU values. A CIRS electron density phantom was scanned on a Siemens Biograph mCT Flow CT scanner and a GE Discovery 710 CT scanner using standard techniques that are employed in the clinic to assess the HU deviation caused by beam hardening in different tissue types. In addition, an anthropomorphic ATOM adult male upper torso phantom was scanned on the GE Discovery 710 scanner. Various amounts of Superflab bolus material were wrapped around the phantoms to simulate different patient sizes. The mean HU values that were measured in the phantoms were evaluated as a function of the water-equivalent area (A w ), a parameter that is described in the report of AAPM Task Group 220. A strategy by which to correct the HU values was developed and tested. The variation in the HU values in the anthropomorphic ATOM phantom under different simulated body sizes, both before and after correction, were compared, with a focus on the lung and bone tissues. Significant HU deviations that depended on the simulated patient size were observed. A positive correlation between HU and A w was observed for tissue types that have an HU of less than zero, while a negative correlation was observed for tissue types with HU values that are greater than zero. The magnitude of the difference increases as the underlying attenuation property deviates further away from that of water. In the electron density phantom study, the maximum observed HU differences between the measured and reference values in the cortical bone and lung materials were 426 and 94 HU, respectively. In the anthropomorphic phantom

PBL Trigger Design by Medical Students: An Effective Active Learning Strategy Outside the Classroom.

Science.gov (United States)

Roche, Maya; Adiga, Indira Kakkunje; Nayak, Akshatha G

2016-12-01

Problem Based Learning (PBL) is known world over as an effective, active learning strategy with many benefits for the student. Usually, in medical schools, PBL triggers are designed by a well-trained group of faculty from basic and clinical sciences. The challenge was whether this task could be given to students in the first year of their curriculum and be executed by them effectively. To enhance active learning, comprehension and critical thinking with a view to promote horizontal and vertical integration between subjects. Student volunteers of the first year MBBS course (n=10), who had been exposed to the curriculum for approximately 38 weeks and were familiar with the PBL process were recruited for the study. In addition to a handout on the topic 'gout', they were given the freedom to access any resource in the university library to construct the PBL triggers. The PBL triggers were vetted by two faculties. In addition to a focus group discussion with students, students' and faculty's responses were collected on a Likert scale. Students opined that the exercise helped improve their comprehension (100%), critical thinking abilities (90%) and clinical orientation to the topic (100%). They felt that designing a PBL trigger was a relevant active learning strategy (100%) and would help them answer questions on this topic better in the future (90%). The clinicians who examined the PBL triggers, felt that they were of good quality and that the process was a good tool for vertical integration between basic and clinical sciences. The results prove that students when given a challenge will rise to the occasion. Unfamiliarity with the nuances of a disease did not prevent them from going the extra mile to achieve their target. By taking part in this exercise, students benefitted in many ways and got a holistic understanding of the topic. PBL trigger design can be introduced as an active learning strategy for students in medical schools where PBL is part of the curriculum. It

SU-E-T-470: Importance of HU-Mass Density Calibration Technique in Proton Pencil Beam Dose Calculation

Energy Technology Data Exchange (ETDEWEB)

Penfold, S; Miller, A [University of Adelaide, Adelaide, SA (Australia)

2015-06-15

Purpose: Stoichiometric calibration of Hounsfield Units (HUs) for conversion to proton relative stopping powers (RStPs) is vital for accurate dose calculation in proton therapy. However proton dose distributions are not only dependent on RStP, but also on relative scattering power (RScP) of patient tissues. RScP is approximated from material density but a stoichiometric calibration of HU-density tables is commonly neglected. The purpose of this work was to quantify the difference in calculated dose of a commercial TPS when using HU-density tables based on tissue substitute materials and stoichiometric calibrated ICRU tissues. Methods: Two HU-density calibration tables were generated based on scans of the CIRS electron density phantom. The first table was based directly on measured HU and manufacturer quoted density of tissue substitute materials. The second was based on the same CT scan of the CIRS phantom followed by a stoichiometric calibration of ICRU44 tissue materials. The research version of Pinnacle{sup 3} proton therapy was used to compute dose in a patient CT data set utilizing both HU-density tables. Results: The two HU-density tables showed significant differences for bone tissues; the difference increasing with increasing HU. Differences in density calibration table translated to a difference in calculated RScP of −2.5% for ICRU skeletal muscle and 9.2% for ICRU femur. Dose-volume histogram analysis of a parallel opposed proton therapy prostate plan showed that the difference in calculated dose was negligible when using the two different HU-density calibration tables. Conclusion: The impact of HU-density calibration technique on proton therapy dose calculation was assessed. While differences were found in the calculated RScP of bony tissues, the difference in dose distribution for realistic treatment scenarios was found to be insignificant.

Analysis Critical Thinking Stage of Eighth Grade in PBL-Scaffolding Setting To Solve Mathematical Problems

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Nur Aisyah Isti

2017-03-01

Full Text Available The purpose of this research was described critical thinking stage of students grade VIII in setting PBL and scaffolding to solve mathematics problems. Critical thinking stage consists of clarification, assesment, inference, and strategy/tactics. The subject were teo students in the level of capacity to think critical (uncritical, less critical, quite critical, and critical. So that this research subject was 8 students in VIII A One State Junior High School of Temanggung. The result showed a description (1 critical thinking stage of students in setting PBL, in clarification the higher level of capacity to think critical students, students can identification information from question fully, can identificatio problem became detailed, and can explored the relationship among the information; (2 a strategy of scaffolding were given by critical thinking stage and TKBK, in assesment, scaffolding had given was given hint/key classically; and (3 transformation characteristic of the critical thinking stage of students after given scaffolding, it because of habituation in setting PBL and scaffolding.

Quantitative assessment of periimplant bone density (HU) on CBCT image

International Nuclear Information System (INIS)

Goo, Jong Gook; Kim, Jin Soo; Kim, Jae Duk

2008-01-01

The primary aims of this retrospective study were to compare subjective bone quality and bone quality based on the Hounsfield scale in different segments of the edentulous jaw, and to establish quantitative and objective assessment of the bone quality. Twenty eight randomly selected cone-beam computed tomographic (CBCT) scans were analyzed. For evaluation one hundred and twelve edentulous areas were selected. Implant recipient sites were evaluated visually for Lekholm and Zarb classification. The same sites were subsequently evaluated digitally using the Hounsfield scale with Vimplant 2.0 TM , and the results were correlated with visual classification. Data was subject for statistical analysis in order to determine correlation between recorded HU and the regions of the mouth with the Kruskal-Wallis test. The highest unit/mean density value (311 HU) was found in the anterior mandible, followed by 259 HU for the posterior mandible, 216 HU for the anterior maxilla, and 127 HU for the posterior maxilla. These results demonstrate a strong correlation for HU depending on the region of the mouth (p TM with Vimplant TM software.

Decision PBL: A 4-year retrospective case study of the use of virtual patients in problem-based learning.

Science.gov (United States)

Ellaway, Rachel H; Poulton, Terry; Jivram, Trupti

2015-01-01

In 2009, St George's University of London (SGUL) replaced their paper-based problem-based learning (PBL) cases with virtual patients for intermediate-level undergraduate students. This involved the development of Decision-Problem-Based Learning (D-PBL), a variation on progressive-release PBL that uses virtual patients instead of paper cases, and focuses on patient management decisions and their consequences. Using a case study method, this paper describes four years of developing and running D-PBL at SGUL from individual activities up to the ways in which D-PBL functioned as an educational system. A number of broad issues were identified: the importance of debates and decision-making in making D-PBL activities engaging and rewarding; the complexities of managing small group dynamics; the time taken to complete D-PBL activities; the changing role of the facilitator; and the erosion of the D-PBL process over time. A key point in understanding this work is the construction and execution of the D-PBL activity, as much of the value of this approach arises from the actions and interactions of students, their facilitators and the virtual patients rather than from the design of the virtual patients alone. At a systems level D-PBL needs to be periodically refreshed to retain its effectiveness.

Integrating Sustainability in a PBL Environment for Electronics Engineering

DEFF Research Database (Denmark)

Arsat, Mahyuddin; Holgaard, Jette Egelund; de Graaff, Erik

2013-01-01

(PBL) has been put forward as a promising pedagogical model and emerged as an opportunity to implement sustainability successfully. Due to the almost forty years of experience in PBL, a case study was carried out at Aalborg University, Denmark to excerpt their experience of integrating sustainability...... in a problem based learning environment. Three electronics engineering project modules were selected as example and empirically supported by constructed interviews with staff and document analysis of selected material. The findings were analysed with a systems approach and presented with reference to three...

Infecciones en huéspedes inmunocomprometidos

Directory of Open Access Journals (Sweden)

Luis Ernesto Cuéllar Ponce de León

2013-04-01

Full Text Available Las infecciones son causa frecuente de morbimortalidad en huéspedes inmunocomprometidos. La frecuencia y diversidad de infecciones en esta población dependerá del tipo de inmunocompromiso, tratamiento recibido y aspecto epidemiológico. Los huéspedes con neutropenia desarrollan infecciones por bacterias extracelulares no encapsuladas y hongos levaduriformes y filamentosos; el diagnóstico precoz y tratamiento oportuno de las mismas son considerados una emergencia por su severidad y gran mortalidad asociada. El compromiso de la inmunidad humoral se relaciona con infecciones por microorganismos encapsulados (bacterias extracelulares y hongos; la secuencia clínica presentada en estas infecciones es neumonía aguda-bacteremia/fungemia-meningoencefalitis aguda/crónica. Muchas de estas infecciones son inmunoprevenibles. Los huéspedes con compromiso de la inmunidad celular desarrollan infecciones por microorganismos intracelulares y también por algunos extracelulares; muchas de las infecciones ocurren por reactivación; a menudo requieren profilaxis antimicrobiana tanto primaria como secundaria. El tratamiento medicamentoso (quimioterapia, drogas inmunosupresoras, etc. y los procedimientos invasivos facilitan el desarrollo de determinadas infecciones. El aspecto epidemiológico, que incluye el estilo de vida, ocupación, viajes previos, etc. permite evaluar y determinar el riesgo de potenciales infecciones. En conclusión, la prevención de las infecciones y el uso racional de antimicrobianos son los pilares fundamentales en el manejo efectivo de los huéspedes inmunocomprometidos.

A probabilistic Hu-Washizu variational principle

Science.gov (United States)

Liu, W. K.; Belytschko, T.; Besterfield, G. H.

1987-01-01

A Probabilistic Hu-Washizu Variational Principle (PHWVP) for the Probabilistic Finite Element Method (PFEM) is presented. This formulation is developed for both linear and nonlinear elasticity. The PHWVP allows incorporation of the probabilistic distributions for the constitutive law, compatibility condition, equilibrium, domain and boundary conditions into the PFEM. Thus, a complete probabilistic analysis can be performed where all aspects of the problem are treated as random variables and/or fields. The Hu-Washizu variational formulation is available in many conventional finite element codes thereby enabling the straightforward inclusion of the probabilistic features into present codes.

3D printing in social education: Eki-Fab and student PBL

Science.gov (United States)

Makino, Masato; Saito, Azusa; Kodama, Mai; Takamatsu, Kyuuichiro; Tamate, Hideaki; Sakai, Kazuyuki; Wada, Masato; Khosla, Ajit; Kawakami, Masaru; Furukawa, Hidemitsu

2017-04-01

Additive manufacturing or 3D printer is one of the most innovative material processing methods. We are considering that human resources for 3D printing would be needed in the future. To educate the abilities of the digital fabrication, we have the public digital fabrication space "Eki-Fab" for junior and high school students and Project Based Learning (PBL) class for undergraduate students. Eki-Fab is held on every Saturday at the Yonezawa train station. In the "Eki-Fab", anybody can study the utilizing of 3D printer and modeling technics under the instruction of staff in Yamagata University. In the PBL class, we have the class every Thursday. The students get the techniques of the digital fabrication through the PBL.

ANALISIS DESKRIPTIF DALAM PENERAPAN MODEL PEMBELAJARAN PBL (PROBLEM BASED LEARNING OLEH GURU MATA PELAJARAN EKONOMI SMA NEGERI 1 SLIYEG KABUPATEN INDRAMAYU

Directory of Open Access Journals (Sweden)

Sheilla Az Zahra

2015-06-01

Sliyeg (3 Evaluation of PBL learning by teachers of Economics. The method used in this study is a qualitative method. The research was conducted in SMAN 1 Sliyeg Indramayu district. Data analysis is an analysis tool interaction. Techniques of data collection using interviews and documentation. Key informants were social studies teachers, Science, and Mathematics. Data analysis techniques in the study include: data collection, data reduction, data display and conclusion drawing or verification data. The results showed that teachers Economics lesson in SMAN 1 Sliyeg always made at the beginning of the semester learning devices and always arrange and prepare lesson plans sebelu mmengajar. Implementation of PBL learning by Economics teacher is good enough and the teacher was quite understand about PBL and chances, positive trespon of students. Evaluation and assessment of Economics teachers each have a different way, such as quizzes and question and answer, and then the teacher members additional value to students who are active in answering. The advice given in this research is the teacher should improve the understanding of the PBL learning. Teachers must be knowledgeable, increase kretivitas and innovative in the implementation of PBL. Teachers should broaden horizons and be more creative in developing ways of evaluation at the end of the lesson.

An Application of Context- and Problem-Based Learning (C-PBL) into Teaching Thermodynamics

Science.gov (United States)

Baran, Mukadder; Sozbilir, Mustafa

2017-05-01

This study aims to investigate the applicability of context- and problem-based learning (C-PBL) into teaching thermodynamics and to examine its influence on the students' achievements in chemistry, retention of knowledge, students' attitudes, motivation and interest towards chemistry. The embedded mixed method design was utilized with a group of 13 chemistry students in a 2-year program of "Medical Laboratory and Techniques" at a state university in an underdeveloped city at the southeastern region of Turkey. The research data were collected via questionnaires regarding the students' attitudes, motivation and interest in chemistry, an achievement test on "thermodynamics" and interviews utilized to find out the applicability of C-PBL into thermodynamics. The findings demonstrated that C-PBL led a statistically significant increase in the students' achievement in thermodynamics and their interest in chemistry, while no statistically significant difference was observed in the students' attitudes and motivation towards chemistry before and after the intervention. The interviews revealed that C-PBL developed not only the students' communication skills but also their skills in using time effectively, making presentations, reporting research results and using technology. It was also found to increase their self-confidence together with the positive attitudes towards C-PBL and being able to associate chemistry with daily life. In light of these findings, it could be stated that it will be beneficial to increase the use of C-PBL in teaching chemistry.

Adenosine Deaminase (ADA)-Deficient Severe Combined Immune Deficiency (SCID): Molecular Pathogenesis and Clinical Manifestations.

Science.gov (United States)

Bradford, Kathryn L; Moretti, Federico A; Carbonaro-Sarracino, Denise A; Gaspar, Hubert B; Kohn, Donald B

2017-10-01

Deficiency of adenosine deaminase (ADA, EC3.5.4.4), a housekeeping enzyme of purine metabolism encoded by the Ada gene, is a cause of human severe combined immune deficiency (SCID). Numerous deleterious mutations occurring in the ADA gene have been found in patients with profound lymphopenia (T - B - NK - ), thus underscoring the importance of functional purine metabolism for the development of the immune defense. While untreated ADA SCID is a fatal disorder, there are multiple life-saving therapeutic modalities to restore ADA activity and reconstitute protective immunity, including enzyme replacement therapy (ERT), allogeneic hematopoietic stem cell transplantation (HSCT) and gene therapy (GT) with autologous gene-corrected hematopoietic stem cells (HSC). We review the pathogenic mechanisms and clinical manifestations of ADA SCID.

Understanding "Green Chemistry" and "Sustainability": An Example of Problem-Based Learning (PBL)

Science.gov (United States)

Günter, Tugçe; Akkuzu, Nalan; Alpat, Senol

2017-01-01

Background: This study uses problem-based learning (PBL) to ensure that students comprehend the significance of green chemistry better by experiencing the stages of identifying the problem, developing hypotheses, and providing solutions within the problem-solving process. Purpose: The aim of this study is to research the effect of PBL implemented…

Bex1 knock out mice show altered skeletal muscle regeneration

International Nuclear Information System (INIS)

Koo, Jae Hyung; Smiley, Mark A.; Lovering, Richard M.; Margolis, Frank L.

2007-01-01

Bex1 and Calmodulin (CaM) are upregulated during skeletal muscle regeneration. We confirm this finding and demonstrate the novel finding that they interact in a calcium-dependent manner. To study the role of Bex1 and its interaction with CaM in skeletal muscle regeneration, we generated Bex1 knock out (Bex1-KO) mice. These mice appeared to develop normally and are fertile, but displayed a functional deficit in exercise performance compared to wild type (WT) mice. After intramuscular injection of cardiotoxin, which causes extensive and reproducible myotrauma followed by recovery, regenerating muscles of Bex1-KO mice exhibited elevated and prolonged cell proliferation, as well as delayed cell differentiation, compared to WT mice. Thus, our results provide the first evidence that Bex1-KO mice show altered muscle regeneration, and allow us to propose that the interaction of Bex1 with Ca 2+ /CaM may be involved in skeletal muscle regeneration

Autoimmune manifestations in SCID due to IL7R mutations: Omenn syndrome and cytopenias.

Science.gov (United States)

Zago, Claudia Augusta; Jacob, Cristina Miuki Abe; de Albuquerque Diniz, Edna Maria; Lovisolo, Silvana Maria; Zerbini, Maria Claudia Nogueira; Dorna, Mayra; Watanabe, Letícia; Fernandes, Juliana Folloni; Rocha, Vanderson; Oliveira, João Bosco; Carneiro-Sampaio, Magda

2014-07-01

B+NK+SCID (severe combined immunodeficiency) due to IL7Rα deficiency represents approximately 10% of American SCID cases. To better understand the spectrum of autoimmune disorders associated with IL7Rα deficiency, we describe two unrelated IL7Rα-deficient female SCID infants whose clinical picture was dominated by autoimmune manifestations: one with intrauterine Omenn syndrome (OS) and another with persistent thrombocytopenic purpura since 4months of age. The OS baby harbored a homozygous p.C118Y mutation in IL7R. She presented dense eosinophilic infiltrates in several organs, including pancarditis, which may have contributed to her death (on the 2nd day of life). B cells were observed in lymph nodes, spleen, bone marrow and thymus. The second patient harbored compound heterozygous p.C118Y and p.I121NfsX8 mutations. She underwent a successful unrelated cord blood transplant. In conclusion, early OS can be observed in patients with IL7R mutations, and autoimmune cytopenias could also complicate the clinical course of SCID babies with this type of defect. Copyright © 2014. Published by Elsevier Inc.

PBL Trigger Design by Medical Students: An Effective Active Learning Strategy Outside the Classroom

Science.gov (United States)

Adiga, Indira Kakkunje; Nayak, Akshatha G.

2016-01-01

Introduction Problem Based Learning (PBL) is known world over as an effective, active learning strategy with many benefits for the student. Usually, in medical schools, PBL triggers are designed by a well-trained group of faculty from basic and clinical sciences. The challenge was whether this task could be given to students in the first year of their curriculum and be executed by them effectively. Aim To enhance active learning, comprehension and critical thinking with a view to promote horizontal and vertical integration between subjects. Materials and Methods Student volunteers of the first year MBBS course (n=10), who had been exposed to the curriculum for approximately 38 weeks and were familiar with the PBL process were recruited for the study. In addition to a handout on the topic ‘gout’, they were given the freedom to access any resource in the university library to construct the PBL triggers. The PBL triggers were vetted by two faculties. In addition to a focus group discussion with students, students’ and faculty’s responses were collected on a Likert scale. Results Students opined that the exercise helped improve their comprehension (100%), critical thinking abilities (90%) and clinical orientation to the topic (100%). They felt that designing a PBL trigger was a relevant active learning strategy (100%) and would help them answer questions on this topic better in the future (90%). The clinicians who examined the PBL triggers, felt that they were of good quality and that the process was a good tool for vertical integration between basic and clinical sciences. Discussion The results prove that students when given a challenge will rise to the occasion. Unfamiliarity with the nuances of a disease did not prevent them from going the extra mile to achieve their target. By taking part in this exercise, students benefitted in many ways and got a holistic understanding of the topic. Conclusion PBL trigger design can be introduced as an active learning

The problem-based learning (PBL and health education.

Directory of Open Access Journals (Sweden)

Carine Moraes Vignochi

2009-05-01

Full Text Available The Problem-Based Learning (Problem-Based Learning - PBL has been recognized worldwide as an approach to promote the acquisition of knowledge by students at the same time that helps them develop skills and professional attitudes desirable. Unlike the conventional methods of teaching that use of application problems after the theory was presented, the PBL uses a problem to start, focus and motivate the learning of new concepts 13. In this approach, the student uses different mental processes, such as ability to raise hypotheses, compare, analyze, interpret, and evaluate and develop the ability to take responsibility for their education 11.12. The methodology of PBL has been a valuable tool in shaping the health care professional, with advantages over the traditional method of teaching. However, for its deployment there is a need for considerable institutional effort. Are necessary adjustments, including changes in the way of evaluation, for changes in mindset about the role of teachers in the process teaching / learning, investment in infrastructure, adaptations of the environment, improvement of libraries and other 19,20,21, 22. The process of change in education will bring many challenges, such as a break with traditional models of education and train health professionals with skills to recover the essential dimension of care: the relationship between humans.

Micrometeorological and PBL experiments in Australia

Science.gov (United States)

Garratt, J. R.; Hicks, B. B.

1990-03-01

A brief summary is given of five main field experiments (or sets of expeditions) carried out in Australia in the last thirty years. The main objectives and results of each are described, and an indication is given of their impact on progress in our understanding of the planetary boundary layer (PBL).

MicroRNA-16 Modulates HuR Regulation of Cyclin E1 in Breast Cancer Cells

Directory of Open Access Journals (Sweden)

Xun Guo

2015-03-01

Full Text Available RNA binding protein (RBPs and microRNAs (miRNAs or miRs are post-transcriptional regulators of gene expression that are implicated in development of cancers. Although their individual roles have been studied, the crosstalk between RBPs and miRNAs is under intense investigation. Here, we show that in breast cancer cells, cyclin E1 upregulation by the RBP HuR is through specific binding to regions in the cyclin E1 mRNA 3' untranslated region (3'UTR containing U-rich elements. Similarly, miR-16 represses cyclin E1, dependent on its cognate binding sites in the cyclin E1 3'UTR. Evidence in the literature indicates that HuR can regulate miRNA expression and recruit or dissociate RNA-induced silencing complexes (RISC. Despite this, miR-16 and HuR do not affect the other’s expression level or binding to the cyclin E1 3'UTR. While HuR overexpression partially blocks miR-16 repression of a reporter mRNA containing the cyclin E1 3'UTR, it does not block miR-16 repression of endogenous cyclin E1 mRNA. In contrast, miR-16 blocks HuR-mediated upregulation of cyclin E1. Overall our results suggest that miR-16 can override HuR upregulation of cyclin E1 without affecting HuR expression or association with the cyclin E1 mRNA.

Preliminary look at the diurnal behavior of the PBL

International Nuclear Information System (INIS)

Hess, G.D.; Sisterson, D.L.; Hicks, B.B.; Miller, E.L.

1975-01-01

Atmospheric factors that govern the dispersion and transport of air pollutants discussed include the behavior of the planetary boundary layer (PBL) during the morning hours, beginning before the sun rises; the influence of surface heating after the sun rises on erosion of the base of the nocturnal inversion; and the influence wind speed and height and temperature on mixing throughout the boundary layer. It is pointed out that many of the processes occurring within the PBL must be parameterized in numerical models rather than being directly calculated since they occur on scales smaller than the resolution of the models

The effect of combining recombinant human tumor necrosis factor-alpha with local radiation on tumor control probability of a human glioblastoma multiforme xenograft in nude mice

International Nuclear Information System (INIS)

Huang, Peigen; Allam, Ayman; Perez, Luis A.; Taghian, Alphonse; Freeman, Jill; Suit, Herman D.

1995-01-01

Purpose: To evaluate the antitumor activity of recombinant human tumor necrosis factor-alpha (rHuTNF-α) on a human glioblastoma multiforme (U87) xenograft in nude mice, and to study the effect of combining rHuTNF-α with local radiation on the tumor control probability of this tumor model. Methods and Materials: U87 xenograft was transplanted SC into the right hindleg of NCr/Sed nude mice (7-8 weeks old, male). When tumors reached a volume of about 110 mm 3 , mice were randomly assigned to treatment: rHuTNF-α alone compared with normal saline control; or local radiation plus rHuTNF-α vs. local radiation plus normal saline. Parameters of growth delay, volume doubling time, percentage of necrosis, and cell loss factor were used to assess the antitumor effects of rHuTNF-α on this tumor. The TCD 50 (tumor control dose 50%) was used as an endpoint to determine the effect of combining rHuTNF-α with local radiation. Results: Tumor growth in mice treated with a dose of 150 μg/kg body weight rHuTNF-α, IP injection daily for 7 consecutive days, was delayed about 8 days compared to that in controls. Tumors in the treatment group had a significantly longer volume doubling time, and were smaller in volume and more necrotic than matched tumors in control group. rHuTNF-α also induced a 2.3 times increase of cell loss factor. The administration of the above-mentioned dose of rHuTNF-α starting 24 h after single doses of localized irradiation under hypoxic condition, resulted in a significant reduction in TCD 50 from the control value of 60.9 Gy to 50.5 Gy (p 50 value in the treatment vs. the control groups

The effect of combining recombinant human tumor necrosis factor-alpha with local radiation on tumor control probability of a human glioblastoma multiforme xenograft in nude mice

Energy Technology Data Exchange (ETDEWEB)

Huang, Peigen; Allam, Ayman; Perez, Luis A; Taghian, Alphonse; Freeman, Jill; Suit, Herman D

1995-04-30

Purpose: To evaluate the antitumor activity of recombinant human tumor necrosis factor-alpha (rHuTNF-{alpha}) on a human glioblastoma multiforme (U87) xenograft in nude mice, and to study the effect of combining rHuTNF-{alpha} with local radiation on the tumor control probability of this tumor model. Methods and Materials: U87 xenograft was transplanted SC into the right hindleg of NCr/Sed nude mice (7-8 weeks old, male). When tumors reached a volume of about 110 mm{sup 3}, mice were randomly assigned to treatment: rHuTNF-{alpha} alone compared with normal saline control; or local radiation plus rHuTNF-{alpha} vs. local radiation plus normal saline. Parameters of growth delay, volume doubling time, percentage of necrosis, and cell loss factor were used to assess the antitumor effects of rHuTNF-{alpha} on this tumor. The TCD{sub 50} (tumor control dose 50%) was used as an endpoint to determine the effect of combining rHuTNF-{alpha} with local radiation. Results: Tumor growth in mice treated with a dose of 150 {mu}g/kg body weight rHuTNF-{alpha}, IP injection daily for 7 consecutive days, was delayed about 8 days compared to that in controls. Tumors in the treatment group had a significantly longer volume doubling time, and were smaller in volume and more necrotic than matched tumors in control group. rHuTNF-{alpha} also induced a 2.3 times increase of cell loss factor. The administration of the above-mentioned dose of rHuTNF-{alpha} starting 24 h after single doses of localized irradiation under hypoxic condition, resulted in a significant reduction in TCD{sub 50} from the control value of 60.9 Gy to 50.5 Gy (p < 0.01). Conclusion: rHuTNF-{alpha} exhibits an antitumor effect against U87 xenograft in nude mice, as evidenced by an increased delay in tumor growth as well as cell loss factor. Also, there was an augmentation of tumor curability when given in combination with radiotherapy, resulting in a significantly lower TCD{sub 50} value in the treatment vs. the

Jumping the PBL Implementation Hurdle: Supporting the Efforts of K-12 Teachers

Science.gov (United States)

Ertmer, Peggy A.; Simons, Krista D.

2006-01-01

While problem-based learning (PBL) has a relatively long history of successful use in medical and pre-professional schools, it has yet to be widely adopted by K--12 teachers. This may be due, in part, to the numerous challenges teachers experience when implementing PBL. In this paper, we describe specific hurdles that teachers are likely to…

The «PBL WORKING ENVIRONMENT» as interactive and expert system to learn the problem-based learning method

Directory of Open Access Journals (Sweden)

Susana Correnti

2016-01-01

Full Text Available The «PBL working environment» is a virtual environment developed in the framework of SCENE project (profeSsional development for an effeCtive PBL approach: a practical experiENce through ICT-enabled lEarning solution, co-funded by the European Lifelong Learning Program. The «PBL working environment» is devoted to prepare headmasters and teachers of secondary and vocational schools to use Problem-Based Learning (PBL pedagogy effectively. It is a student-centered pedagogy where learners are «actively» engaged in real world problems to solve or challenges to meet. Students develop problem-solving, self-directed learning and team skills. The «PBL working environment» is an virtual tool including three main elements: e-learning platform, virtual facilitator and PBL repository. Teachers, trainers and headmasters/school managers learn the PBL pedagogy by attending an on-line course (e-learning platform delivered through the «inductive method». It allows learners to experience PBL approach, by practicing it stage by stage, and then learn to turn practice into theory by abstracting their experience to build a theoretical understanding. Since generating the proper scenario is the most critical aspect of PBL, after benefiting from the on-line course, users can benefit from a further support: the Virtual Facilitator. It provides tips and hints on how correctly design a problem scenario and by asking questions to collect data on user's specific needs. The Virtual Facilitator is able to provide a/or more suitable example(s which match as closest as possible the teacher/trainer need. Finally, users can share problem scenarios and projects of different subjects of studies and with different characteristics uploaded and downloaded in the PBL repository.

Pumilio2-deficient mice show a predisposition for epilepsy

Directory of Open Access Journals (Sweden)

Philipp Follwaczny

2017-11-01

Full Text Available Epilepsy is a neurological disease that is caused by abnormal hypersynchronous activities of neuronal ensembles leading to recurrent and spontaneous seizures in human patients. Enhanced neuronal excitability and a high level of synchrony between neurons seem to trigger these spontaneous seizures. The molecular mechanisms, however, regarding the development of neuronal hyperexcitability and maintenance of epilepsy are still poorly understood. Here, we show that pumilio RNA-binding family member 2 (Pumilio2; Pum2 plays a role in the regulation of excitability in hippocampal neurons of weaned and 5-month-old male mice. Almost complete deficiency of Pum2 in adult Pum2 gene-trap mice (Pum2 GT causes misregulation of genes involved in neuronal excitability control. Interestingly, this finding is accompanied by the development of spontaneous epileptic seizures in Pum2 GT mice. Furthermore, we detect an age-dependent increase in Scn1a (Nav1.1 and Scn8a (Nav1.6 mRNA levels together with a decrease in Scn2a (Nav1.2 transcript levels in weaned Pum2 GT that is absent in older mice. Moreover, field recordings of CA1 pyramidal neurons show a tendency towards a reduced paired-pulse inhibition after stimulation of the Schaffer-collateral-commissural pathway in Pum2 GT mice, indicating a predisposition to the development of spontaneous seizures at later stages. With the onset of spontaneous seizures at the age of 5 months, we detect increased protein levels of Nav1.1 and Nav1.2 as well as decreased protein levels of Nav1.6 in those mice. In addition, GABA receptor subunit alpha-2 (Gabra2 mRNA levels are increased in weaned and adult mice. Furthermore, we observe an enhanced GABRA2 protein level in the dendritic field of the CA1 subregion in the Pum2 GT hippocampus. We conclude that altered expression levels of known epileptic risk factors such as Nav1.1, Nav1.2, Nav1.6 and GABRA2 result in enhanced seizure susceptibility and manifestation of epilepsy in the

Spectrum of mutations in a cohort of UK patients with ADA deficient SCID: Segregation of genotypes with specific ethnicities.

Science.gov (United States)

Adams, Stuart P; Wilson, Melanie; Harb, Elissar; Fairbanks, Lynette; Xu-Bayford, Jinhua; Brown, Lucie; Kearney, Laura; Madkaikar, Manisha; Bobby Gaspar, H

2015-12-01

Severe combined immunodeficiency (SCID) arises from a number of different genetic defects, one of the most common being mutations in the gene encoding adenosine deaminase (ADA). In the UK, ADA deficient SCID compromises approximately 20% of all known cases of SCID. We carried out a retrospective analysis of the ADA gene in 46 known ADA deficient SCID patients on whom DNA had been stored. Here, we report a high frequency of two previously reported mutations and provide a link between the mutations and patient ethnicity within our patient cohort. We also report on 9 novel mutations that have been previously unreported. Copyright © 2015 Elsevier Inc. All rights reserved.

Ultra-Sensitive HIV-1 Latency Viral Outgrowth Assays Using Humanized Mice.

Science.gov (United States)

Schmitt, Kimberly; Akkina, Ramesh

2018-01-01

In the current quest for a complete cure for HIV/AIDS, highly sensitive HIV-1 latency detection methods are critical to verify full viral eradication. Until now, the in vitro quantitative viral outgrowth assays (qVOA) have been the gold standard for assessing latent HIV-1 viral burden. However, these assays have been inadequate in detecting the presence of ultralow levels of latent virus in a number of patients who were initially thought to have been cured, but eventually showed viral rebound. In this context, new approaches utilizing in vivo mouse-based VOAs are promising. In the murine VOA (mVOA), large numbers of CD4 + T cells or PBMC from aviremic subjects are xenografted into immunodeficient NSG mice, whereas in the humanized mouse-based VOA (hmVOA) patient CD4 + T cell samples are injected into BLT or hu-hematopoetic stem cells (hu-HSC) humanized mice. While latent virus could be recovered in both of these systems, the hmVOA provides higher sensitivity than the mVOA using a fewer number of input cells. In contrast to the mVOA, the hmVOA provides a broader spectrum of highly susceptible HIV-1 target cells and enables newly engrafted cells to home into preformed human lymphoid organs where they can infect cells in situ after viral activation. Hu-mice also allow for both xenograft- and allograft-driven cell expansions with less severe GvH providing a longer time frame for potential viral outgrowth from cells with a delayed latent viral activation. Based on these advantages, the hmVOA has great potential in playing an important role in HIV-1 latency and cure research.

PBL structure: the Sangamon Experiment of 1975

International Nuclear Information System (INIS)

Hess, G.D.; Hicks, B.B.

1975-01-01

The environmental impact of a number of fossil-fuel power plants in Illinois was investigated using numerical models of air pollution effects for a regional analysis. As a part of this study a field study (the Sangamon Experiment) was conducted during 1975 to examine physical mechanisms in the planetary boundary layer (PBL). This experiment was coordinated with the Midwest Interstate Sulfur Transformation and Transport (MISTT) project to investigate the effects of the urban plume emanating from St. Louis at distances of up to 100 km. Results are reported from studies on the evolution of the PBL capping inversion between the hours of 0400 and 1200; micrometeorological studies over maize and soybean crops growing in the area; measurements of wind speed, turbulence, and temperature in the lowest 100 m of the atmosphere; and measurements of the concentration of ozone, sulfur dioxide, nitrogen dioxide, and hydrocarbons in air samples from a kytoon system

Transcriptomic-Wide Discovery of Direct and Indirect HuR RNA Targets in Activated CD4+ T Cells.

Directory of Open Access Journals (Sweden)

Patsharaporn Techasintana

Full Text Available Due to poor correlation between steady state mRNA levels and protein product, purely transcriptomic profiling methods may miss genes posttranscriptionally regulated by RNA binding proteins (RBPs and microRNAs (miRNAs. RNA immunoprecipitation (RIP methods developed to identify in vivo targets of RBPs have greatly elucidated those mRNAs which may be regulated via transcript stability and translation. The RBP HuR (ELAVL1 and family members are major stabilizers of mRNA. Many labs have identified HuR mRNA targets; however, many of these analyses have been performed in cell lines and oftentimes are not independent biological replicates. Little is known about how HuR target mRNAs behave in conditional knock-out models. In the present work, we performed HuR RIP-Seq and RNA-Seq to investigate HuR direct and indirect targets using a novel conditional knock-out model of HuR genetic ablation during CD4+ T activation and Th2 differentiation. Using independent biological replicates, we generated a high coverage RIP-Seq data set (>160 million reads that was analyzed using bioinformatics methods specifically designed to find direct mRNA targets in RIP-Seq data. Simultaneously, another set of independent biological replicates were sequenced by RNA-Seq (>425 million reads to identify indirect HuR targets. These direct and indirect targets were combined to determine canonical pathways in CD4+ T cell activation and differentiation for which HuR plays an important role. We show that HuR may regulate genes in multiple canonical pathways involved in T cell activation especially the CD28 family signaling pathway. These data provide insights into potential HuR-regulated genes during T cell activation and immune mechanisms.

Teachers' Perspectives of their roles and student autonomy in a PBL context in China

DEFF Research Database (Denmark)

Li, Huichun; Du, Xiangyun

2015-01-01

in a PBL context. In particular, we are mainly concerned with teachers’ attitudes towards student learning autonomy in PBL contexts. The data is mainly relied upon in-depth interviews of the teachers who participate in PBL practice from the two cases. When focusing on how teachers perceive student learning...... autonomy, we can note three major patterns. In general, Chinese teachers have a tendency to maintain high interference in student learning process even though they admit the value of giving student learning autonomy. This study further indicates a dilemma between teachers’ intention to encourage students...

Teaching practice of the course of Laser Principle and Application based on PBL mode

Science.gov (United States)

Li, Yongliang; Lv, Beibei; Wang, Siqi

2017-08-01

The primary task of university education is to stimulate students' autonomic learning and cultivate students' creative thinking. This paper put to use problem based learning (PBL) teaching mode, to enable students master flexible knowledge as the goal, and a detailed analysis of the implementation method and concrete measures of PBL teaching reform in the course of Laser Principle and Application, then compared with the former teaching methods. From the feedback of students and teaching experience, we get good teaching effect and prove the feasibility of PBL teaching mode in practice.

Introducing problem-based learning (PBL) into a foundation ...

African Journals Online (AJOL)

constructivist case study was located in evaluation research. .... Approval to proceed with this study was granted by the university ethics .... to PBL, students shifted their learning conceptions from mere textbook learning ..... business education.

Notas sobre el paisaje de Huánuco Pampa

OpenAIRE

Román Godines, Oscar; Ministerio de Cultura

2013-01-01

El complejo arqueológico Huánuco Pampa se encuentra ubicado en la provincia Dos de Mayo en el departamento de Huánuco y en la actualidad es quizás el principal vestigio de la cosmovisión y la planificación urbana inca.

The type 2 cannabinoid receptor regulates susceptibility to osteoarthritis in mice.

Science.gov (United States)

Sophocleous, A; Börjesson, A E; Salter, D M; Ralston, S H

2015-09-01

Cannabinoid receptors and their ligands have been implicated in the regulation of various physiological processes but their role in osteoarthritis has not been investigated. The aim of this study was to evaluate the role of the type 2 cannabinoid receptor (Cnr2) in regulating susceptibility to osteoarthritis in mice. We analysed the severity of knee osteoarthritis as assessed by the Osteoarthritis Research Society International (OARSI) scoring system in mice with targeted deletion of Cnr2 (Cnr2(-/-)) and wild type (WT) littermates. Studies were conducted in mice subjected to surgical destabilisation of the medial meniscus (DMM) and in those with spontaneous age-related osteoarthritis (OA). Osteoarthritis was more severe following DMM in the medial compartment of the knee in Cnr2(-/-) compared with WT mice (mean ± sem score = 4.9 ± 0.5 vs 3.6 ± 0.3; P = 0.017). Treatment of WT mice with the CB2-selective agonist HU308 following DMM reduced the severity of OA in the whole joint (HU308 = 8.4 ± 0.2 vs vehicle = 10.4 ± 0.6; P = 0.007). Spontaneous age related osteoarthritis was also more severe in the medial compartment of the knee in 12-month old Cnr2(-/-) mice compared with WT (5.6 ± 0.5 vs 3.5 ± 0.3, P = 0.008). Cultured articular chondrocytes from Cnr2(-/-) mice produced less proteoglycans in vitro than wild type chondrocytes. These studies demonstrate that the Cnr2 pathway plays a role in the pathophysiology of osteoarthritis in mice and shows that pharmacological activation of CB2 has a protective effect. Further studies of the role of cannabinoid receptors in the pathogenesis of osteoarthritis in man are warranted. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

A humanised murine monoclonal antibody protects mice from Venezuelan equine encephalitis virus, Everglades virus and Mucambo virus when administered up to 48 h after airborne challenge

Energy Technology Data Exchange (ETDEWEB)

O' Brien, Lyn M., E-mail: lmobrien@dstl.gov.uk; Goodchild, Sarah A.; Phillpotts, Robert J.; Perkins, Stuart D.

2012-05-10

Currently there are no licensed antiviral treatments for the Alphaviruses Venezuelan equine encephalitis virus (VEEV), Everglades virus and Mucambo virus. We previously developed a humanised version of the mouse monoclonal antibody 1A3B-7 (Hu1A3B-7) which exhibited a wide range of reactivity in vitro and was able to protect mice from infection with VEEV. Continued work with the humanised antibody has now demonstrated that it has the potential to be a new human therapeutic. Hu1A3B-7 successfully protected mice from infection with multiple Alphaviruses. The effectiveness of the humanisation process was determined by assessing proliferation responses in human T-cells to peptides derived from the murine and humanised versions of the V{sub H} and V{sub L} domains. This analysis showed that the number of human T-cell epitopes within the humanised antibody had been substantially reduced, indicating that Hu1A3B-7 may have reduced immunogenicity in vivo.

A humanised murine monoclonal antibody protects mice from Venezuelan equine encephalitis virus, Everglades virus and Mucambo virus when administered up to 48 h after airborne challenge

International Nuclear Information System (INIS)

O'Brien, Lyn M.; Goodchild, Sarah A.; Phillpotts, Robert J.; Perkins, Stuart D.

2012-01-01

Currently there are no licensed antiviral treatments for the Alphaviruses Venezuelan equine encephalitis virus (VEEV), Everglades virus and Mucambo virus. We previously developed a humanised version of the mouse monoclonal antibody 1A3B-7 (Hu1A3B-7) which exhibited a wide range of reactivity in vitro and was able to protect mice from infection with VEEV. Continued work with the humanised antibody has now demonstrated that it has the potential to be a new human therapeutic. Hu1A3B-7 successfully protected mice from infection with multiple Alphaviruses. The effectiveness of the humanisation process was determined by assessing proliferation responses in human T-cells to peptides derived from the murine and humanised versions of the V H and V L domains. This analysis showed that the number of human T-cell epitopes within the humanised antibody had been substantially reduced, indicating that Hu1A3B-7 may have reduced immunogenicity in vivo.

Mice lacking hippocampal left-right asymmetry show non-spatial learning deficits.

Science.gov (United States)

Shimbo, Akihiro; Kosaki, Yutaka; Ito, Isao; Watanabe, Shigeru

2018-01-15

Left-right asymmetry is known to exist at several anatomical levels in the brain and recent studies have provided further evidence to show that it also exists at a molecular level in the hippocampal CA3-CA1 circuit. The distribution of N-methyl-d-aspartate (NMDA) receptor NR2B subunits in the apical and basal synapses of CA1 pyramidal neurons is asymmetrical if the input arrives from the left or right CA3 pyramidal neurons. In the present study, we examined the role of hippocampal asymmetry in cognitive function using β2-microglobulin knock-out (β2m KO) mice, which lack hippocampal asymmetry. We tested β2m KO mice in a series of spatial and non-spatial learning tasks and compared the performances of β2m KO and C57BL6/J wild-type (WT) mice. The β2m KO mice appeared normal in both spatial reference memory and spatial working memory tasks but they took more time than WT mice in learning the two non-spatial learning tasks (i.e., a differential reinforcement of lower rates of behavior (DRL) task and a straight runway task). The β2m KO mice also showed less precision in their response timing in the DRL task and showed weaker spontaneous recovery during extinction in the straight runway task. These results indicate that hippocampal asymmetry is important for certain characteristics of non-spatial learning. Copyright © 2017 Elsevier B.V. All rights reserved.

Domain-specific phosphomimetic mutation allows dissection of different protein kinase C (PKC) isotype-triggered activities of the RNA binding protein HuR.

Science.gov (United States)

Schulz, Sebastian; Doller, Anke; Pendini, Nicole R; Wilce, Jacqueline A; Pfeilschifter, Josef; Eberhardt, Wolfgang

2013-12-01

The ubiquitous mRNA binding protein human antigen R (HuR) participates in the post-transcriptional regulation of many AU-rich element (ARE)-bearing mRNAs. Previously, by using in vitro kinase assay, we have identified serines (Ser) 158, 221 and 318 as targets of protein kinase C (PKC)-triggered phosphorylation. In this study, we tested whether GFP- or GST-tagged HuR constructs bearing a phosphomimetic Ser (S)-to-Asp (D) substitution at the different PKC target sites, would affect different HuR functions including HuR nucleo-cytoplasmic redistribution and binding to different types of ARE-containing mRNAs. The phosphomimetic GFP-tagged HuR protein bearing a phosphomimetic substitution in the hinge region of HuR (HuR-S221D) showed an increased cytoplasmic abundance when compared to wild-type HuR. Conversely, data from in vitro kinase assay and electrophoretic mobility shift assay (EMSA), implicates that phosphorylation at Ser 221 is not relevant for mRNA binding of HuR. Quantification of in vitro binding affinities of GST-tagged wild-type HuR and corresponding HuR proteins bearing a phosphomimetic substitution in either RRM2 (HuR-S158D) or in RRM3 (HuR-S318D) by microscale thermophoresis (MST) indicates a specific binding of wild-type HuR to type I, II or type III-ARE-oligonucleotides in the high nanomolar range. Interestingly, phosphomimetic mutation at position 158 or 318 had a negative influence on HuR binding to type I- and type II-ARE-mRNAs whereas it significantly enhanced HuR affinity to a type III-ARE substrate. Our data suggest that differential phosphorylation of HuR by PKCs at different HuR domains coordinates subcellular HuR distribution and leads to a preferential binding to U-rich bearing target mRNA. © 2013.

PBL in the Era of Reform Standards: Challenges and Benefits Perceived by Teachers in One Elementary School

Science.gov (United States)

Nariman, Nahid; Chrispeels, Janet

2016-01-01

We explore teachers' efforts to implement problem-based learning (PBL) in an elementary school serving predominantly English learners. Teachers had an opportunity to implement the Next Generation Science Standards (NGSS) using PBL in a summer school setting with no test-pressures. To understand the challenges and benefits of PBL implementation, a…

Detrimental ELAVL-1/HuR-dependent GSK3β mRNA stabilization impairs resolution in acute respiratory distress syndrome.

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Olivia Hoffman

Full Text Available A hallmark of acute respiratory distress syndrome (ARDS is accumulation of protein-rich edema in the distal airspaces and its removal is critical for patient survival. Previous studies have shown a detrimental role of Glycogen Synthase Kinase (GSK 3β during ARDS via inhibition of alveolar epithelial protein transport. We hypothesized that post-transcriptional regulation of GSK3β could play a functional role in ARDS resolution. To address this hypothesis, we performed an in silico analysis to identify regulatory genes whose expression correlation to GSK3β messenger RNA utilizing two lung cancer cell line array datasets. Among potential regulatory partners of GSK3β, these studies identified the RNA-binding protein ELAVL-1/HuR (Embryonic Lethal, Abnormal Vision, Drosophila-Like as a central component in a likely GSK3β signaling network. ELAVL-1/HuR is a RNA-binding protein that selectively binds to AU-rich elements of mRNA and enhances its stability thereby increasing target gene expression. Subsequent studies with siRNA suppression of ELAVL-1/HuR demonstrated deceased GSK3β mRNA and protein expression and improved clearance of FITC-albumin in A549 cells. Conversely, stabilization of ELAVL-1/HuR with the proteasome inhibitor MG-132 resulted in induction of GSK3β at mRNA and protein level and attenuated FITC-albumin clearance. Utilizing ventilator-induced lung injury or intra-tracheal installation of hydrochloric acid to induce ARDS in mice, we observed increased mRNA and protein expression of ELAVL-1/HuR and GSK3β. Together, our findings indicate a previously unknown interaction between GSK3β and ELAV-1 during ARDS, and suggest the inhibition of the ELAV-1- GSK3β pathways as a novel ARDS treatment approach.

PENINGKATAN KEMAMPUAN PEMECAHAN MASALAH DAN PENGEMBANGAN KARAKTER PADA SISWA KELAS VII MELALUI MODEL PBL BERBANTUAN SCAFFOLDING

OpenAIRE

Novy Kris Zaini; Wuryanto Wuryanto; Hery Sutarto

2016-01-01

Tujuan penelitian ini adalah untuk mengetahui (1) apakah kemampuan pemecahan masalah matematika peserta didik yang diajar dengan model PBL berbantuan scaffolding pada materi pokok segiempat kelas VII dapat mencapai KKM yang ditetapkan, (2) apakah pembelajaran matematika dengan model PBL berbantuan scaffolding pada materi pokok segiempat kelas VII dapat meningkatkan kemampuan pemecahan masalah peserta didik pilihan, (3) apakah pembelajaran matematika dengan model PBL berbantuan scaffolding pad...

Twenty-Five Years of Gene Therapy for ADA-SCID: From Bubble Babies to an Approved Drug.

Science.gov (United States)

Ferrua, Francesca; Aiuti, Alessandro

2017-11-01

Twenty-five years have passed since first attempts of gene therapy (GT) in children affected by severe combined immunodeficiency (SCID) due to adenosine deaminase (ADA) defect, also known by the general public as bubble babies. ADA-SCID is fatal early in life if untreated. Unconditioned hematopoietic stem cell (HSC) transplant from matched sibling donor represents a curative treatment but is available for few patients. Enzyme replacement therapy can be life-saving, but its chronic use has many drawbacks. This review summarizes the history of ADA-SCID GT over the last 25 years, starting from first pioneering studies in the early 1990s using gamma-retroviral vectors, based on multiple infusions of genetically corrected autologous peripheral blood lymphocytes. HSC represented the ideal target for gene correction to guarantee production of engineered multi-lineage progeny, but it required a decade to achieve therapeutic benefit with this approach. Introduction of low-intensity conditioning represented a crucial step in achieving stable gene-corrected HSC engraftment and therapeutic levels of ADA-expressing cells. Recent clinical trials demonstrated that gamma-retroviral GT for ADA-SCID has a favorable safety profile and is effective in restoring normal purine metabolism and immune functions in patients >13 years after treatment. No abnormal clonal proliferation or leukemia development have been observed in >40 patients treated experimentally in five different centers worldwide. In 2016, the medicinal product Strimvelis™ received marketing approval in Europe for patients affected by ADA-SCID without a suitable human leukocyte antigen-matched related donor. Positive safety and efficacy results have been obtained in GT clinical trials using lentiviral vectors encoding ADA. The results obtained in last 25 years in ADA-SCID GT development fundamentally contributed to improve patients' prognosis, together with earlier diagnosis thanks to newborn screening. These advances

Introducing problem-based learning (PBL) into a foundation ...

African Journals Online (AJOL)

second chance learners they cannot be taught by the same traditional methods that ... a shift from content coverage to problem engagement; from lecturing to coaching; and ..... Project on the effectiveness of Problem Based Learning (PBL).

Potential utility of eGFP-expressing NOG mice (NOG-EGFP as a high purity cancer sampling system

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Shima Kentaro

2012-06-01

Full Text Available Abstract Purpose It is still technically difficult to collect high purity cancer cells from tumor tissues, which contain noncancerous cells. We hypothesized that xenograft models of NOG mice expressing enhanced green fluorescent protein (eGFP, referred to as NOG-EGFP mice, may be useful for obtaining such high purity cancer cells for detailed molecular and cellular analyses. Methods Pancreato-biliary cancer cell lines were implanted subcutaneously to compare the tumorigenicity between NOG-EGFP mice and nonobese diabetic/severe combined immunodeficiency (NOD/SCID mice. To obtain high purity cancer cells, the subcutaneous tumors were harvested from the mice and enzymatically dissociated into single-cell suspensions. Then, the cells were sorted by fluorescence-activated cell sorting (FACS for separation of the host cells and the cancer cells. Thereafter, the contamination rate of host cells in collected cancer cells was quantified by using FACS analysis. The viability of cancer cells after FACS sorting was evaluated by cell culture and subsequent subcutaneous reimplantation in NOG-EGFP mice. Results The tumorigenicity of NOG-EGFP mice was significantly better than that of NOD/SCID mice in all of the analyzed cell lines (p  Conclusions This method provides a novel cancer sampling system for molecular and cellular analysis with high accuracy and should contribute to the development of personalized medicine.

Scheduled transplantation of human umbilical cord blood to severe combined immunodeficient mice

International Nuclear Information System (INIS)

Wu Jianqiu; Yang Yunfang; Jin Zhijun; Cai Jianming; Yang Rujun; Xiang Yingsong

2000-01-01

Objective: To explore a new method for developing the efficiency of human umbilical cord blood (UCB) cells engraftment, and further understand the growth characteristic of hematopoietic stem cells (HSC) in vivo. Methods: Sublethally irradiated severe combined immunodeficient (SCID) mice were transplanted i.v. with UCB cells which had been cryo-preserved at -80 degree C. The human cells in recipient mice were detected by flow cytometry and CFU-GM assay. Results: In contrast to the single transplantation, scheduled engraftment of similar numbers of UCB cells resulted in a proportionally obvious increase in the percentages of CD45 + , CD34 + cells produced in SCID mouse bone marrow (BM). When the donor cells were reduced to 20 percent, an identical reconstitution of both hematopoietic and part of immunologic functions was achieved. Conclusion: Scheduled engraftment improves the repopulating ability of HSC, which would provide a novel way for clinical cord blood engraftment in adult objects

Sensitivity of land-atmosphere exchanges to overshooting PBL thermals in an idealized coupled model

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Ian T. Baker

2009-11-01

Full Text Available The response of atmospheric carbon dioxide to a given amount of surface flux is inversely proportional to the depth of the planetary boundary layer (PBL. Overshooting thermals that entrain free tropospheric air down into the boundary layer modify the characteristics and depth of the mixed layer through the insertion of energy and mass. In addition, entrainment "dilutes" the effects of surface fluxes on scalar quantities (temperature, water vapor, carbon dioxide, etc. in the PBL. Therefore, incorrect simulation of PBL depth can lead to linear errors in estimates of carbon dioxide fluxes in inverse models. Dilution by entrainment directly alters the surface-air gradients in scalar properties, which serve as the "driving force" for surface fluxes. In addition, changes in near-surface temperature and water vapor affect surface fluxes through physiological processes in plant canopies (e.g. stomatal conductance. Although overshooting thermals are important in the physical world, their effects are unresolved in most regional models. We explore the sensitivity of surface fluxes and PBL scalars to the intensity of PBL top entrainment by manipulating its strength in an idealized version of the coupled SiB-RAMS model. An entrainment parameterization based on the virtual potential temperature flux at the surface is implemented into SiB-RAMS to produce a warmer and drier mixed layer, to alter the surface fluxes, and to increase the depth of the PBL. These variations produce modified CO₂ concentrations and vary with the strength of the parameterized entrainment.

BDNF-Deficient Mice Show Reduced Psychosis-Related Behaviors Following Chronic Methamphetamine.

Science.gov (United States)

Manning, Elizabeth E; Halberstadt, Adam L; van den Buuse, Maarten

2016-04-01

One of the most devastating consequences of methamphetamine abuse is increased risk of psychosis. Brain-derived neurotrophic factor has been implicated in both psychosis and neuronal responses to methamphetamine. We therefore examined persistent psychosis-like behavioral effects of methamphetamine in brain-derived neurotrophic factor heterozygous mice. Mice were chronically treated with methamphetamine from 6 to 9 weeks of age, and locomotor hyperactivity to an acute D-amphetamine challenge was tested in photocell cages after a 2-week withdrawal period. Methamphetamine-treated wild-type mice, but not brain-derived neurotrophic factor heterozygous mice, showed locomotor sensitization to acute 3mg/kg D-amphetamine. Qualitative analysis of exploration revealed tolerance to D-amphetamine effects on entropy in methamphetamine-treated brain-derived neurotrophic factor heterozygous mice, but not wild-type mice. Chronic methamphetamine exposure induces contrasting profiles of behavioral changes in wild-type and brain-derived neurotrophic factor heterozygous mice, with attenuation of behaviors relevant to psychosis in methamphetamine-treated brain-derived neurotrophic factor heterozygous mice. This suggests that brain-derived neurotrophic factor signalling changes may contribute to development of psychosis in methamphetamine users. © The Author 2015. Published by Oxford University Press on behalf of CINP.

Improved Human Erythropoiesis and Platelet Formation in Humanized NSGW41 Mice

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Susann Rahmig

2016-10-01

Full Text Available Human erythro-megakaryopoiesis does not occur in humanized mouse models, preventing the in vivo analysis of human hematopoietic stem cell (HSC differentiation into these lineages in a surrogate host. Here we show that stably engrafted KIT-deficient NOD/SCID Il2rg−/− KitW41/W41 (NSGW41 mice support much improved human erythropoiesis and platelet formation compared with irradiated NSG recipients. Considerable numbers of human erythroblasts and mature thrombocytes are present in the bone marrow and blood, respectively. Morphology, composition, and enucleation capacity of de novo generated human erythroblasts in NSGW41 mice are comparable with those in human bone marrow. Overexpression of human erythropoietin showed no further improvement in human erythrocyte output, but depletion of macrophages led to the appearance of human erythrocytes in the blood. Human erythropoiesis up to normoblasts and platelet formation is fully supported in NSGW41 mice, allowing the analysis of human HSC differentiation into these lineages, the exploration of certain pathophysiologies, and the evaluation of gene therapeutic approaches.

Comparison of the Debye–Hückel and the Mean Spherical Approximation Theories for Electrolyte Solutions

DEFF Research Database (Denmark)

Maribo-Mogensen, Bjørn; Kontogeorgis, Georgios M.; Thomsen, Kaj

2012-01-01

The thermodynamics of electrolyte solutions has been investigated by many scientists throughout the last century. While several theories have been presented, the most popular models for the electrostatic interactions are based on the Debye–Hückel and mean spherical approximation (MSA) theories....... In this paper we investigate the differences between the Debye–Hückel and the MSA theories, and comparisons of the numerical results for the Helmholtz energy and its derivatives with respect to temperature, volume and composition are presented. The investigation shows that the nonrestricted primitive MSA...... theory performs similarly to Debye–Hückel, despite the differences in the derivation. We furthermore show that the static permittivity is a key parameter for both models and that in many cases it completely dominates the results obtained from the two models. Consequently, we conclude that the simpler...

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

Energy Technology Data Exchange (ETDEWEB)

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.)

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.)

Adapted PBL Practical Exercises: Benefits for Apprentices

Science.gov (United States)

Monks, Alan

2010-01-01

Use was made of adapted problem-based learning (PBL) practical exercises to address the disengagement of apprentices with the existing assembly-style electronic laboratory programme. Apprentices perceived the traditional routines as having little real-world relevance. This detracted from the value and benefit to them of the practical component of…

Mice deficient in PAPP-A show resistance to the development of diabetic nephropathy.

Science.gov (United States)

Mader, Jessica R; Resch, Zachary T; McLean, Gary R; Mikkelsen, Jakob H; Oxvig, Claus; Marler, Ronald J; Conover, Cheryl A

2013-10-01

We investigated pregnancy-associated plasma protein-A (PAPP-A) in diabetic nephropathy. Normal human kidney showed specific staining for PAPP-A in glomeruli, and this staining was markedly increased in diabetic kidney. To assess the possible contribution of PAPP-A in the development of diabetic nephropathy, we induced diabetes with streptozotocin in 14-month-old WT and Papp-A knockout (KO) mice. Renal histopathology was evaluated after 4 months of stable hyperglycemia. Kidneys from diabetic WT mice showed multiple abnormalities including thickening of Bowman's capsule (100% of mice), increased glomerular size (80% of mice), tubule dilation (80% of mice), and mononuclear cell infiltration (90% of mice). Kidneys of age-matched non-diabetic WT mice had similar evidence of tubule dilation and mononuclear cell infiltration to those of diabetic WT mice, indicating that these changes were predominantly age-related. However, thickened Bowman's capsule and increased glomerular size appeared specific for the experimental diabetes. Kidneys from diabetic Papp-A KO mice had significantly reduced or no evidence of changes in Bowman's capsule thickening and glomerular size. There was also a shift to larger mesangial area and increased macrophage staining in diabetic WT mice compared with Papp-A KO mice. In summary, elevated PAPP-A expression in glomeruli is associated with diabetic nephropathy in humans and absence of PAPP-A is associated with resistance to the development of indicators of diabetic nephropathy in mice. These data suggest PAPP-A as a potential therapeutic target for diabetic nephropathy.

PBL scaling using surface flux information

International Nuclear Information System (INIS)

Hess, G.D.; Hicks, B.B.

1975-01-01

The role of the atmospheric planetary boundary layer (PBL) in the transport and dispersion of air pollutants is discussed. It is pointed out that because the physical processes controlling the structure in the lowest one to two km of the atmosphere can be complex, interpretation of observational data is often ambiguous. The value of similarity theory for interpreting experimental data and for designing field experiments is discussed

Influence of PBL with open-book tests on knowledge retention measured with progress tests

NARCIS (Netherlands)

Heijne-Penninga, M.; Kuks, J. B. M.; Hofman, W. H. A.; Muijtjens, A. M. M.; Cohen-Schotanus, J.

The influence of problem-based learning (PBL) and open-book tests on long-term knowledge retention is unclear and subject of discussion. Hypotheses were that PBL as well as open-book tests positively affect long-term knowledge retention. Four progress test results of fifth and sixth-year medical

Blocking Breast Cancer Metastasis by Targeting RNA-Binding Protein HuR

Science.gov (United States)

2017-10-01

AWARD NUMBER: W81XWH-16-1-0730 TITLE: Blocking Breast Cancer Metastasis by Targeting RNA-Binding Protein HuR PRINCIPAL INVESTIGATOR: Danny Welch...NUMBER Blocking Breast Cancer Metastasis by Targeting RNA-Binding Protein HuR 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...increased aggressiveness in breast cancer , the primary objective of this proposal is to assess whether HuR (or analogs) prevent and/or treat metastasis and/or

Application of Project-Based Learning (PBL) to the Teaching of Electrical Power Systems Engineering

Science.gov (United States)

Hosseinzadeh, N.; Hesamzadeh, M. R.

2012-01-01

Project-based learning (PBL), a learning environment in which projects drive learning, has been successfully used in various courses in the educational programs of different disciplines. However, concerns have been raised as to the breadth of the content covered and, in particular, whether PBL can be applied to specialized subjects without…

The Importance and Current Limitations of Planetary Boundary Layer (PBL) Retrieval from Space for Land-Atmosphere Coupling Studies

Science.gov (United States)

Santanello, J. A., Jr.; Schaefer, A.

2016-12-01

There is an established need for improved PBL remote sounding over land for hydrology, land-atmosphere (L-A), PBL, cloud/convection, pollution/chemistry studies and associated model evaluation and development. Most notably, the connection of surface hydrology (through soil moisture) to clouds and precipitation relies on proper quantification of water's transport through the coupled system, which is modulated strongly by PBL structure, growth, and feedback processes such as entrainment. In-situ (ground-based or radiosonde) measurements will be spatially limited to small field campaigns for the foreseeable future, so satellite data is a must in order to understand these processes globally. The scales of these applications require diurnal resolution (e.g. 3-hourly or finer) at land-PBL coupling and water and energy cycles at their native scales. Today's satellite sensors (e.g. advanced IR, GEO, lidar, GPS-RO) do not reach close to these targets in terms of accuracy or resolution, and each of these sensors has some advantages but even more limitations that make them impractical for PBL and L-A studies. Unfortunately, there is very little attention or planning (short or long-term) in place for improving lower tropospheric sounding over land, and as a result PBL and L-A interactions have been identified as `gaps' in current programmatic focal areas. It is therefore timely to assess how these technologies can be leveraged, combined, or evolved in order to form a dedicated mission or sub-mission to routinely monitor the PBL on diurnal timescales. In addition, improved PBL monitoring from space needs to be addressed in the next Decadal Survey. In this talk, the importance of PBL information (structure, evolution) for L-A coupling diagnostics and model development will be summarized. The current array of PBL retrieval methods and products from space will then be assessed in terms of meeting the needs of these models, diagnostics, and scales, with a look forward as to how

Supporting traditional PBL with online discussion forums: a study from Qassim Medical School.

Science.gov (United States)

Alamro, Ahmad S; Schofield, Susie

2012-01-01

The Qassim Medical School first year curriculum includes a 5-week problem-based learning (PBL) block. Student evaluation has highlighted inadequate feedback and lack of student-student and student-tutor interactions. An online intervention may alleviate this. For each problem, a discussion forum (DF) was created with 14 threads (one for each group) in virtual PBL rooms. Students' and tutors' perceived satisfaction of the intervention was evaluated and types of posts were classified. By the end of the block, all academic staff involved and 123 students (95%) had participated in the DFs. There were around 2800 posts and 28,500 views. All 14 tutors and 102 (78%) students completed the online questionnaire. Of the students, 66 (76%) male and 36 (92%) female students responded. Overall, both students and tutors perceived the intervention positively. Posts included: reforming and finalizing learning objectives, posting the concept map constructed in the face-to-face session and questioning, encouraging and motivating each other. In addition, posts included tutors' feedback and redirection. Blending e-learning with conventional PBL may help overcome student-perceived shortcomings of conventional PBL and improve the learning experience, making learning more interactive and interesting.

Transversal knowledge formations in Professional Bachelor Education employing Problem Based Learning (PBL)

DEFF Research Database (Denmark)

Larsen, Verner

2013-01-01

This paper describes the principles underlying how various knowledge areas blend into transversal formations in two educational contexts employing PBL. Such ‘transversality’ has often been referred to as inter- cross- or trans-disciplinarity. However, these terms are ambiguous, especially...... case studies - Nursing and the Constructing Architect education - have been researched, compared and contrasted in order to demonstrate how institutional practices demonstrate different modalities of transversal knowledge in their PBL-courses. For the purpose of this paper Nursing Education...

The Effectiveness of Problem Based Learning (PBL) on Intermediate Financial Accounting Subject

OpenAIRE

Nunuk Suryanti

2016-01-01

This research aims to know the effectiveness of Problem Based Learning (PBL) Model comparing to Drill Model on Intermediate Financial Accounting subject. The research was a quasi-experimental research. Population was four classes of Accounting Education students in the year of 2014/2015 at Faculty of Educational Science and Teaching of Riau Islamic University (UIR). Sample was taken by using purposive sampling. Then, it used Problem Based Learning (PBL) at experimental class and Drill Model a...

Repeated Gestational Exposure of Mice to Chlorpyrifos Oxon Is Associated with Paraoxonase 1 (PON1) Modulated Effects in Maternal and Fetal Tissues

Science.gov (United States)

Co, Aila L.; Hay, Ariel M.; MacDonald, James W.; Bammler, Theo K.; Farin, Federico M.; Costa, Lucio G.; Furlong, Clement E.

2014-01-01

Chlorpyrifos oxon (CPO), the toxic metabolite of the organophosphorus (OP) insecticide chlorpyrifos, causes developmental neurotoxicity in humans and rodents. CPO is hydrolyzed by paraoxonase-1 (PON1), with protection determined by PON1 levels and the human Q192R polymorphism. To examine how the Q192R polymorphism influences fetal toxicity associated with gestational CPO exposure, we measured enzyme inhibition and fetal-brain gene expression in wild-type (PON1+/+), PON1-knockout (PON1−/−), and tgHuPON1R192 and tgHuPON1Q192 transgenic mice. Pregnant mice exposed dermally to 0, 0.50, 0.75, or 0.85 mg/kg/d CPO from gestational day (GD) 6 through 17 were sacrificed on GD18. Biomarkers of CPO exposure inhibited in maternal tissues included brain acetylcholinesterase (AChE), red blood cell acylpeptide hydrolase (APH), and plasma butyrylcholinesterase (BChE) and carboxylesterase (CES). Fetal plasma BChE was inhibited in PON1−/− and tgHuPON1Q192, but not PON1+/+ or tgHuPON1R192 mice. Fetal brain AChE and plasma CES were inhibited in PON1−/− mice, but not in other genotypes. Weighted gene co-expression network analysis identified five gene modules based on clustering of the correlations among their fetal-brain expression values, allowing for correlation of module membership with the phenotypic data on enzyme inhibition. One module that correlated highly with maternal brain AChE activity had a large representation of homeobox genes. Gene set enrichment analysis revealed multiple gene sets affected by gestational CPO exposure in tgHuPON1Q192 but not tgHuPON1R192 mice, including gene sets involved in protein export, lipid metabolism, and neurotransmission. These data indicate that maternal PON1 status modulates the effects of repeated gestational CPO exposure on fetal-brain gene expression and on inhibition of both maternal and fetal biomarker enzymes. PMID:25070982

Different modes of interaction by TIAR and HuR with target RNA and DNA

OpenAIRE

Kim, Henry S.; Wilce, Matthew C. J.; Yoga, Yano M. K.; Pendini, Nicole R.; Gunzburg, Menachem J.; Cowieson, Nathan P.; Wilson, Gerald M.; Williams, Bryan R. G.; Gorospe, Myriam; Wilce, Jacqueline A.

2011-01-01

TIAR and HuR are mRNA-binding proteins that play important roles in the regulation of translation. They both possess three RNA recognition motifs (RRMs) and bind to AU-rich elements (AREs), with seemingly overlapping specificity. Here we show using SPR that TIAR and HuR bind to both U-rich and AU-rich RNA in the nanomolar range, with higher overall affinity for U-rich RNA. However, the higher affinity for U–rich sequences is mainly due to faster association with U-rich RNA, which we propose i...

Enhanced normal short-term human myelopoiesis in mice engineered to express human-specific myeloid growth factors.

Science.gov (United States)

Miller, Paul H; Cheung, Alice M S; Beer, Philip A; Knapp, David J H F; Dhillon, Kiran; Rabu, Gabrielle; Rostamirad, Shabnam; Humphries, R Keith; Eaves, Connie J

2013-01-31

Better methods to characterize normal human hematopoietic cells with short-term repopulating activity cells (STRCs) are needed to facilitate improving recovery rates in transplanted patients.We now show that 5-fold more human myeloid cells are produced in sublethally irradiated NOD/SCID-IL-2Receptor-γchain-null (NSG) mice engineered to constitutively produce human interleukin-3, granulocyte-macrophage colony-stimulating factor and Steel factor (NSG-3GS mice) than in regular NSG mice 3 weeks after an intravenous injection of CD34 human cord blood cells. Importantly, the NSG-3GS mice also show a concomitant and matched increase in circulating mature human neutrophils. Imaging NSG-3GS recipients of lenti-luciferase-transduced cells showed that human cells being produced 3 weeks posttransplant were heterogeneously distributed, validating the blood as a more representative measure of transplanted STRC activity. Limiting dilution transplants further demonstrated that the early increase in human granulopoiesis in NSG-3GS mice reflects an expanded output of differentiated cells per STRC rather than an increase in STRC detection. NSG-3GS mice support enhanced clonal outputs from human short-term repopulating cells (STRCs) without affecting their engrafting efficiency. Increased human STRC clone sizes enable their more precise and efficient measurement by peripheral blood monitoring.

Genital herpes simplex virus type 2 infection in humanized HIV-transgenic mice triggers HIV shedding and is associated with greater neurological disease.

Science.gov (United States)

Nixon, Briana; Fakioglu, Esra; Stefanidou, Martha; Wang, Yanhua; Dutta, Monica; Goldstein, Harris; Herold, Betsy C

2014-02-15

Epidemiological studies consistently demonstrate synergy between herpes simplex virus type 2 (HSV-2) and human immunodeficiency virus type 1 (HIV-1). Higher HIV-1 loads are observed in coinfected individuals, and conversely, HIV-1 is associated with more-severe herpetic disease. A small animal model of coinfection would facilitate identification of the biological mechanisms underlying this synergy and provide the opportunity to evaluate interventions. Mice transgenic for HIV-1 provirus and human cyclin T1 under the control of a CD4 promoter (JR-CSF/hu-cycT1) were intravaginally infected with HSV-2 and evaluated for disease progression, HIV shedding, and mucosal immune responses. HSV-2 infection resulted in higher vaginal HIV loads and genital tissue expression of HIV RNA, compared with HSV-uninfected JR-CSF/hu-cycT1 mice. There was an increase in genital tract inflammatory cells, cytokines, chemokines, and interferons in response to HSV-2, although the kinetics of the response were delayed in HIV-transgenic, compared with control mice. Moreover, the JR-CSF/hu-cycT1 mice exhibited earlier and more-severe neurological disease. The latter was associated with downregulation of secretory leukocyte protease inhibitor expression in neuronal tissue, a molecule with antiinflammatory, antiviral, and neuroprotective properties. JR-CSF/hu-cycT1 mice provide a valuable model to study HIV/HSV-2 coinfection and identify potential mechanisms by which HSV-2 facilitates HIV-1 transmission and HIV modulates HSV-2-mediated disease.

A Qualitative Study on How Health Professional Students and Their PBL Facilitators Perceive the Use of Mobile Devices during PBL

Science.gov (United States)

Chan, Lap Ki; Bridges, Susan M.; Doherty, Iain; Ng, Manwa L.; Jin, Jun; Sharma, Neel; Chan, Nam Kiu; Lai, Henrietta Yan Yu

2015-01-01

Mobile devices are increasingly being used by undergraduate students to access online information in the problem-based learning (PBL) process, initially in the self-directed phase, and more recently within face-to-face tutorials. This qualitative study across three undergraduate health professional programs used semi-structured interviews to…

PDZ domain-binding motif of Tax sustains T-cell proliferation in HTLV-1-infected humanized mice

Science.gov (United States)

Artesi, Maria; Jalinot, Pierre

2018-01-01

Human T-cell leukemia virus type 1 (HTLV-1) is the etiological agent of adult T-cell leukemia/lymphoma (ATLL), an aggressive malignant proliferation of activated CD4+ T lymphocytes. The viral Tax oncoprotein is critically involved in both HTLV-1-replication and T-cell proliferation, a prerequisite to the development of ATLL. In this study, we investigated the in vivo contribution of the Tax PDZ domain-binding motif (PBM) to the lymphoproliferative process. To that aim, we examined T-cell proliferation in humanized mice (hu-mice) carrying a human hemato-lymphoid system infected with either a wild type (WT) or a Tax PBM-deleted (ΔPBM) provirus. We observed that the frequency of CD4+ activated T-cells in the peripheral blood and in the spleen was significantly higher in WT than in ΔPBM hu-mice. Likewise, human T-cells collected from WT hu-mice and cultivated in vitro in presence of interleukin-2 were proliferating at a higher level than those from ΔPBM animals. We next examined the association of Tax with the Scribble PDZ protein, a prominent regulator of T-cell polarity, in human T-cells analyzed either after ex vivo isolation or after in vitro culture. We confirmed the interaction of Tax with Scribble only in T-cells from the WT hu-mice. This association correlated with the presence of both proteins in aggregates at the leading edge of the cells and with the formation of long actin filopods. Finally, data from a comparative genome-wide transcriptomic analysis suggested that the PBM-PDZ association is implicated in the expression of genes regulating proliferation, apoptosis and cytoskeletal organization. Collectively, our findings suggest that the Tax PBM is an auxiliary motif that contributes to the sustained growth of HTLV-1 infected T-cells in vivo and in vitro and is essential to T-cell immortalization. PMID:29566098

PDZ domain-binding motif of Tax sustains T-cell proliferation in HTLV-1-infected humanized mice.

Science.gov (United States)

Pérès, Eléonore; Blin, Juliana; Ricci, Emiliano P; Artesi, Maria; Hahaut, Vincent; Van den Broeke, Anne; Corbin, Antoine; Gazzolo, Louis; Ratner, Lee; Jalinot, Pierre; Duc Dodon, Madeleine

2018-03-01

Human T-cell leukemia virus type 1 (HTLV-1) is the etiological agent of adult T-cell leukemia/lymphoma (ATLL), an aggressive malignant proliferation of activated CD4+ T lymphocytes. The viral Tax oncoprotein is critically involved in both HTLV-1-replication and T-cell proliferation, a prerequisite to the development of ATLL. In this study, we investigated the in vivo contribution of the Tax PDZ domain-binding motif (PBM) to the lymphoproliferative process. To that aim, we examined T-cell proliferation in humanized mice (hu-mice) carrying a human hemato-lymphoid system infected with either a wild type (WT) or a Tax PBM-deleted (ΔPBM) provirus. We observed that the frequency of CD4+ activated T-cells in the peripheral blood and in the spleen was significantly higher in WT than in ΔPBM hu-mice. Likewise, human T-cells collected from WT hu-mice and cultivated in vitro in presence of interleukin-2 were proliferating at a higher level than those from ΔPBM animals. We next examined the association of Tax with the Scribble PDZ protein, a prominent regulator of T-cell polarity, in human T-cells analyzed either after ex vivo isolation or after in vitro culture. We confirmed the interaction of Tax with Scribble only in T-cells from the WT hu-mice. This association correlated with the presence of both proteins in aggregates at the leading edge of the cells and with the formation of long actin filopods. Finally, data from a comparative genome-wide transcriptomic analysis suggested that the PBM-PDZ association is implicated in the expression of genes regulating proliferation, apoptosis and cytoskeletal organization. Collectively, our findings suggest that the Tax PBM is an auxiliary motif that contributes to the sustained growth of HTLV-1 infected T-cells in vivo and in vitro and is essential to T-cell immortalization.

Isolation and characterization of a catalase gene "HuCAT3" from pitaya (Hylocereus undatus) and its expression under abiotic stress.

Science.gov (United States)

Nie, Qiong; Gao, Guo-Li; Fan, Qing-jie; Qiao, Guang; Wen, Xiao-Peng; Liu, Tao; Peng, Zhi-Jun; Cai, Yong-Qiang

2015-05-25

Abiotic stresses usually cause H2O2 accumulation, with harmful effects, in plants. Catalase may play a key protective role in plant cells by detoxifying this excess H2O2. Pitaya (Hylocereus undatus) shows broad ecological adaptation due to its high tolerance to abiotic stresses, e.g. drought, heat and poor soil. However, involvement of the pitaya catalase gene (HuCAT) in tolerance to abiotic stresses is unknown. In the present study, a full-length HuCAT3 cDNA (1870 bp) was isolated from pitaya based on our previous microarray data and RACE method. The cDNA sequence and deduced amino acid sequence shared 73-77% and 75-80% identity with other plant catalases, respectively. HuCAT3 contains conserved catalase family domain and catalytic sites. Pairwise comparison and phylogenetic analysis indicated that HuCAT3 is most similar to Eriobotrya japonica CAT, followed by Dimocarpus longan CAT and Nicotiana tabacum CAT1. Expression profile analysis demonstrated that HuCAT3 is mainly expressed in green cotyledons and mature stems, and was regulated by H2O2, drought, cold and salt stress, whereas, its expression patterns and maximum expression levels varied with stress types. HuCAT activity increased as exposure to the tested stresses, and the fluctuation of HuCAT activity was consistent with HuCAT3 mRNA abundance (except for 0.5 days upon drought stress). HuCAT3 mRNA elevations and HuCAT activities changes under cold stress were also in conformity with the cold tolerances among the four genotypes. The obtained results confirmed a major role of HuCAT3 in abiotic stress response of pitaya. This may prove useful in understanding pitaya's high tolerance to abiotic stresses at molecular level. Copyright © 2015 Elsevier B.V. All rights reserved.

The scid mutation does not affect slowly repairing potentially lethal damage that is sensitive to 0.23 M NaCl

International Nuclear Information System (INIS)

Kimura, Hiroshi; Ikebuchi, Makoto; Fushiki, Masato; Komatsu, Kenshi.

1996-01-01

The repair of slowly repairing potentially lethal damage (PLD) in radiosensitive cells from the severe combined immunodeficient (scid) mouse was compared with that in Balb/c 3T3 cells with ''wild-type'' radiosensitivity and that in RD13B2 cells derived from scid cells whose sensitivity is normal because of the presence of fragments of human chromosome 8. Treatment with 0.23 M NaCl was used for fixation of slowly repairing PLD. The scid cells repaired PLD sensitive to 0.23 M NaCl to a great extent whin 3-4 h, similarly to Balb/c 3T3 and RD13B2 cells. This indicates that the scid mutation hardly affects the repair of PLD sensitive to 0.23 M NaCl. On the other hand, as reported previously, the rapidly repairing PLD that is sensitive to 0.5 M NaCl was repaired only slowly (3-4 h) in scid cells, in contrast to the rapid repair (within 1 h) seen with Balb/c 3T3 and RD13B2. This suggests that scid mutation is responsible for this repair at reduced rate. To confirm the independence of repair of 0.23 M NaCl-sensitive PLD from that of 0.5 M NaCl-sensitive PLD, both treatments with 0.23 M NaCl and 0.5 M NaCl were combined in each line. It is found that the repair of either PLD was not affected by the other treatment. The scid mutation impaired only the repair of 0.5 M NaCl-sensitive PLD. (author)

Teaching Environmental Education through PBL: Evaluation of a Teaching Intervention Program

Science.gov (United States)

Vasconcelos, Clara

2012-04-01

If our chosen aim in science education is to be inclusive and to improve students' learning achievements, then we must identify teaching methodologies that are appropriate for teaching and learning specific knowledge. Karagiorgi and Symeo 2005) remind us that instructional designers are thus challenged to translate the philosophy of constructivism into current practice. Thus, research in science education must focus on evaluating intervention programs which ensure the effective construction of knowledge and development of competencies. The present study reports the elaboration, application and evaluation of a problem-based learning (PBL) program with the aim of examining its effectiveness with students learning Environmental Education. Prior research on both PBL and Environmental Education (EE) was conducted within the context of science education so as to elaborate and construct the intervention program. Findings from these studies indicated both the PBL methodology and EE as helpful for teachers and students. PBL methodology has been adopted in this study since it is logically incorporated in a constructivism philosophy application (Hendry et al. 1999) and it was expected that this approach would assist students towards achieving a specific set of competencies (Engel 1997). On the other hand, EE has evolved at a rapid pace within many countries in the new millennium (Hart 2007), unlike any other educational area. However, many authors still appear to believe that schools are failing to prepare students adequately in EE (Walsche 2008; Winter 2007). The following section describes the research that was conducted in both areas so as to devise the intervention program.

HuMiTar: A sequence-based method for prediction of human microRNA targets

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Chen Ke

2008-12-01

Full Text Available Abstract Background MicroRNAs (miRs are small noncoding RNAs that bind to complementary/partially complementary sites in the 3' untranslated regions of target genes to regulate protein production of the target transcript and to induce mRNA degradation or mRNA cleavage. The ability to perform accurate, high-throughput identification of physiologically active miR targets would enable functional characterization of individual miRs. Current target prediction methods include traditional approaches that are based on specific base-pairing rules in the miR's seed region and implementation of cross-species conservation of the target site, and machine learning (ML methods that explore patterns that contrast true and false miR-mRNA duplexes. However, in the case of the traditional methods research shows that some seed region matches that are conserved are false positives and that some of the experimentally validated target sites are not conserved. Results We present HuMiTar, a computational method for identifying common targets of miRs, which is based on a scoring function that considers base-pairing for both seed and non-seed positions for human miR-mRNA duplexes. Our design shows that certain non-seed miR nucleotides, such as 14, 18, 13, 11, and 17, are characterized by a strong bias towards formation of Watson-Crick pairing. We contrasted HuMiTar with several representative competing methods on two sets of human miR targets and a set of ten glioblastoma oncogenes. Comparison with the two best performing traditional methods, PicTar and TargetScanS, and a representative ML method that considers the non-seed positions, NBmiRTar, shows that HuMiTar predictions include majority of the predictions of the other three methods. At the same time, the proposed method is also capable of finding more true positive targets as a trade-off for an increased number of predictions. Genome-wide predictions show that the proposed method is characterized by 1.99 signal

Validation of whole-blood transcriptome signature during microdose recombinant human erythropoietin (rHuEpo) administration.

Science.gov (United States)

Wang, Guan; Durussel, Jérôme; Shurlock, Jonathan; Mooses, Martin; Fuku, Noriyuki; Bruinvels, Georgie; Pedlar, Charles; Burden, Richard; Murray, Andrew; Yee, Brendan; Keenan, Anne; McClure, John D; Sottas, Pierre-Edouard; Pitsiladis, Yannis P

2017-11-14

Recombinant human erythropoietin (rHuEpo) can improve human performance and is therefore frequently abused by athletes. As a result, the World Anti-Doping Agency (WADA) introduced the Athlete Biological Passport (ABP) as an indirect method to detect blood doping. Despite this progress, challenges remain to detect blood manipulations such as the use of microdoses of rHuEpo. Forty-five whole-blood transcriptional markers of rHuEpo previously derived from a high-dose rHuEpo administration trial were used to assess whether microdoses of rHuEpo could be detected in 14 trained subjects and whether these markers may be confounded by exercise (n = 14 trained subjects) and altitude training (n = 21 elite runners and n = 4 elite rowers, respectively). Differential gene expression analysis was carried out following normalisation and significance declared following application of a 5% false discovery rate (FDR) and a 1.5 fold-change. Adaptive model analysis was also applied to incorporate these markers for the detection of rHuEpo. ALAS2, BCL2L1, DCAF12, EPB42, GMPR, SELENBP1, SLC4A1, TMOD1 and TRIM58 were differentially expressed during and throughout the post phase of microdose rHuEpo administration. The CD247 and TRIM58 genes were significantly up- and down-regulated, respectively, immediately following exercise when compared with the baseline both before and after rHuEpo/placebo. No significant gene expression changes were found 30 min after exercise in either rHuEpo or placebo groups. ALAS2, BCL2L1, DCAF12, SLC4A1, TMOD1 and TRIM58 tended to be significantly expressed in the elite runners ten days after arriving at altitude and one week after returning from altitude (FDR > 0.059, fold-change varying from 1.39 to 1.63). Following application of the adaptive model, 15 genes showed a high sensitivity (≥ 93%) and specificity (≥ 71%), with BCL2L1 and CSDA having the highest sensitivity (93%) and specificity (93%). Current results provide further evidence that

Identification of an astrovirus commonly infecting laboratory mice in the US and Japan.

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Terry Fei Fan Ng

Full Text Available Mice (Mus musculus are the most commonly used laboratory animals. Viral metagenomics on tissues of immunodeficient mice revealed sequences of a novel mammalian astrovirus. Using PCR, we screened mice from 4 breeders, 4 pharmaceutical companies, 14 research institutes and 30 universities in the US and Japan. Mice from one US breeder tested positive while none from Japanese breeders were positive for MuAstV. Mice in over half of the universities (19/30, institutes (7/14 and pharmaceutical animal facilities (2/4 investigated revealed the presence of MuAstV. Nine mice strains tested positive including both immunodeficient strains (NSG, NOD-SCID, NSG-3GS, C57BL6-Timp-3 (-/-, and uPA-NOG and immunocompetent strains (B6J, ICR, Bash2, BALB/c. Our data indicates that MuAstV has a wide geographical, institutional and host strain distribution. Comparison of the MuAstV RdRp sequences showed numerous mutations indicating ongoing viral divergence in different facilities. This study demonstrates the need for metagenomic screening of laboratory animals to identify adventitious infections that may affect experimental outcomes.

Portraits of PBL: Course Objectives and Students' Study Strategies in Computer Engineering, Psychology and Physiotherapy.

Science.gov (United States)

Dahlgren, Madeleine Abrandt

2000-01-01

Compares the role of course objectives in relation to students' study strategies in problem-based learning (PBL). Results comprise data from three PBL programs at Linkopings University (Sweden), in physiotherapy, psychology, and computer engineering. Faculty provided course objectives to function as supportive structures and guides for students'…

Immunostimulatory effects of natural human interferon-alpha (huIFN-alpha) on carps Cyprinus carpio L.

Science.gov (United States)

Watanuki, Hironobu; Chakraborty, Gunimala; Korenaga, Hiroki; Kono, Tomoya; Shivappa, R B; Sakai, Masahiro

2009-10-15

Human interferon-alpha (huIFN-alpha) is an important immunomodulatory substance used in the treatment and prevention of numerous infectious and immune-related diseases in animals. However, the immunostimulatory effects of huIFN-alpha in fish remain to be investigated. In the current study, the immune responses of the carp species Cyprinus carpio L. to treatment with huIFN-alpha were analyzed via measurement of superoxide anion production, phagocytic activity and the expression of cytokine genes including interleukin-1beta, tumor necrosis factor-alpha and interleukin 10. Low doses of huIFN-alpha were administered orally once a day for 3 days, and sampling was carried out at 1, 3 and 5 days post-treatment. Our results indicate that a low dose of huIFN-alpha significantly increased phagocytic activity and superoxide anion production in the carp kidney. The huIFN-alpha-treated fish also displayed a significant upregulation in cytokine gene expression. The current study demonstrates the stimulatory effects of huIFN-alpha on the carp immune system and highlights the immunomodulatory role of huIFN-alpha in fish.

Activity-dependent expression of ELAV/Hu RBPs and neuronal mRNAs in seizure and cocaine brain.

Science.gov (United States)

Tiruchinapalli, Dhanrajan M; Caron, Marc G; Keene, Jack D

2008-12-01

Growing evidence indicates that both seizure (glutamate) and cocaine (dopamine) treatment modulate synaptic plasticity within the mesolimbic region of the CNS. Activation of glutamatergic neurons depends on the localized translation of neuronal mRNA products involved in modulating synaptic plasticity. In this study, we demonstrate the dendritic localization of HuR and HuD RNA-binding proteins (RBPs) and their association with neuronal mRNAs following these two paradigms of seizure and cocaine treatment. Both the ubiquitously expressed HuR and neuronal HuD RBPs were detected in different regions as well as within dendrites of the brain and in dissociated neurons. Quantitative analysis revealed an increase in HuR, HuD and p-glycogen synthase kinase 3beta (GSK3beta) protein levels as well as neuronal mRNAs encoding Homer, CaMKIIalpha, vascular early response gene, GAP-43, neuritin, and neuroligin protein products following either seizure or cocaine treatment. Inhibition of the Akt/GSK3beta signaling pathway by acute or chronic LiCl treatment revealed changes in HuR, HuD, pGSK3beta, p-Akt, and beta-catenin protein levels. In addition, a genetically engineered hyperdopaminergic mouse model (dopamine transporter knockout) revealed decreased expression of HuR protein levels, but no significant change was observed in HuD or fragile-X mental retardation protein RBPs. Finally, our data suggest that HuR and HuD RBPs potentially interact directly with neuronal mRNAs important for differentiation and synaptic plasticity.

HuR represses Wnt/β-catenin-mediated transcriptional activity by promoting cytoplasmic localization of β-catenin

Energy Technology Data Exchange (ETDEWEB)

Kim, Inae; Hur, Jung; Jeong, Sunjoo, E-mail: sjsj@dankook.ac.kr

2015-01-30

Highlights: • Wnt signaling as well as β-catenin overexpression enhance HuR cytoplasmic export. • HuR overexpression promotes cytoplasmic localization of β-catenin from the perinuclear fraction. • Wnt/β-catenin-mediated transcriptional activity is repressesed by HuR. - Abstract: β-Catenin is the key transcriptional activator of canonical Wnt signaling in the nucleus; thus, nuclear accumulation of β-catenin is a critical step for expressing target genes. β-Catenin accumulates in the nucleus of cancer cells where it activates oncogenic target genes. Hu antigen R (HuR) is a RNA binding protein that regulates multiple post-transcriptional processes including RNA stability. Thus, cytoplasmic HuR protein may be involved in tumorigenesis by stabilizing oncogenic transcripts, but the molecular mechanism remains unclear. Here, we observed that Wnt/β-catenin signaling induced export of the HuR protein, whereas HuR overexpression promoted accumulation of the β-catenin protein in the cytoplasm. Thus, Wnt/β-catenin-mediated transcriptional activity in the nucleus was reduced by overexpressing HuR. These results suggest novel and uncharacterized cytoplasmic β-catenin functions related to HuR-mediated RNA metabolism in cancer cells.

HuR represses Wnt/β-catenin-mediated transcriptional activity by promoting cytoplasmic localization of β-catenin

International Nuclear Information System (INIS)

Kim, Inae; Hur, Jung; Jeong, Sunjoo

2015-01-01

Highlights: • Wnt signaling as well as β-catenin overexpression enhance HuR cytoplasmic export. • HuR overexpression promotes cytoplasmic localization of β-catenin from the perinuclear fraction. • Wnt/β-catenin-mediated transcriptional activity is repressesed by HuR. - Abstract: β-Catenin is the key transcriptional activator of canonical Wnt signaling in the nucleus; thus, nuclear accumulation of β-catenin is a critical step for expressing target genes. β-Catenin accumulates in the nucleus of cancer cells where it activates oncogenic target genes. Hu antigen R (HuR) is a RNA binding protein that regulates multiple post-transcriptional processes including RNA stability. Thus, cytoplasmic HuR protein may be involved in tumorigenesis by stabilizing oncogenic transcripts, but the molecular mechanism remains unclear. Here, we observed that Wnt/β-catenin signaling induced export of the HuR protein, whereas HuR overexpression promoted accumulation of the β-catenin protein in the cytoplasm. Thus, Wnt/β-catenin-mediated transcriptional activity in the nucleus was reduced by overexpressing HuR. These results suggest novel and uncharacterized cytoplasmic β-catenin functions related to HuR-mediated RNA metabolism in cancer cells

Complete Plasmodium falciparum liver-stage development in liver-chimeric mice

Science.gov (United States)

Vaughan, Ashley M.; Mikolajczak, Sebastian A.; Wilson, Elizabeth M.; Grompe, Markus; Kaushansky, Alexis; Camargo, Nelly; Bial, John; Ploss, Alexander; Kappe, Stefan H.I.

2012-01-01

Plasmodium falciparum, which causes the most lethal form of human malaria, replicates in the host liver during the initial stage of infection. However, in vivo malaria liver-stage (LS) studies in humans are virtually impossible, and in vitro models of LS development do not reconstitute relevant parasite growth conditions. To overcome these obstacles, we have adopted a robust mouse model for the study of P. falciparum LS in vivo: the immunocompromised and fumarylacetoacetate hydrolase–deficient mouse (Fah–/–, Rag2–/–, Il2rg–/–, termed the FRG mouse) engrafted with human hepatocytes (FRG huHep). FRG huHep mice supported vigorous, quantifiable P. falciparum LS development that culminated in complete maturation of LS at approximately 7 days after infection, providing a relevant model for LS development in humans. The infections allowed observations of previously unknown expression of proteins in LS, including P. falciparum translocon of exported proteins 150 (PTEX150) and exported protein-2 (EXP-2), components of a known parasite protein export machinery. LS schizonts exhibited exoerythrocytic merozoite formation and merosome release. Furthermore, FRG mice backcrossed to the NOD background and repopulated with huHeps and human red blood cells supported reproducible transition from LS infection to blood-stage infection. Thus, these mice constitute reliable models to study human LS directly in vivo and demonstrate utility for studies of LS–to–blood-stage transition of a human malaria parasite. PMID:22996664

PBL og de sammensatte hold på kandidatuddannelser

DEFF Research Database (Denmark)

Engen, Mie; Fallov, Mia Arp; Jensen, Rune Hagel Skaarup

Denne rapport omhandler pædagogiske udfordringer og muligheder i Aalborgs Problembaserede Læringstilgang (PBL), når den omsættes til pædagogisk og didaktisk handling på kandidatuddannelser med sammensatte hold. Sammensatte hold betyder i denne sammenhæng kandidatuddannelser, hvor de optagne stude...

Coordination of genomic structure and transcription by the main bacterial nucleoid-associated protein HU

Science.gov (United States)

Berger, Michael; Farcas, Anca; Geertz, Marcel; Zhelyazkova, Petya; Brix, Klaudia; Travers, Andrew; Muskhelishvili, Georgi

2010-01-01

The histone-like protein HU is a highly abundant DNA architectural protein that is involved in compacting the DNA of the bacterial nucleoid and in regulating the main DNA transactions, including gene transcription. However, the coordination of the genomic structure and function by HU is poorly understood. Here, we address this question by comparing transcript patterns and spatial distributions of RNA polymerase in Escherichia coli wild-type and hupA/B mutant cells. We demonstrate that, in mutant cells, upregulated genes are preferentially clustered in a large chromosomal domain comprising the ribosomal RNA operons organized on both sides of OriC. Furthermore, we show that, in parallel to this transcription asymmetry, mutant cells are also impaired in forming the transcription foci—spatially confined aggregations of RNA polymerase molecules transcribing strong ribosomal RNA operons. Our data thus implicate HU in coordinating the global genomic structure and function by regulating the spatial distribution of RNA polymerase in the nucleoid. PMID:20010798

HuAc: Human Activity Recognition Using Crowdsourced WiFi Signals and Skeleton Data

Directory of Open Access Journals (Sweden)

Linlin Guo

2018-01-01

Full Text Available The joint of WiFi-based and vision-based human activity recognition has attracted increasing attention in the human-computer interaction, smart home, and security monitoring fields. We propose HuAc, the combination of WiFi-based and Kinect-based activity recognition system, to sense human activity in an indoor environment with occlusion, weak light, and different perspectives. We first construct a WiFi-based activity recognition dataset named WiAR to provide a benchmark for WiFi-based activity recognition. Then, we design a mechanism of subcarrier selection according to the sensitivity of subcarriers to human activities. Moreover, we optimize the spatial relationship of adjacent skeleton joints and draw out a corresponding relationship between CSI and skeleton-based activity recognition. Finally, we explore the fusion information of CSI and crowdsourced skeleton joints to achieve the robustness of human activity recognition. We implemented HuAc using commercial WiFi devices and evaluated it in three kinds of scenarios. Our results show that HuAc achieves an average accuracy of greater than 93% using WiAR dataset.

Occurrence of chai hu (Bupleuri radix) in prescriptions of Chinese herbal medicine in Switzerland.

Science.gov (United States)

Klein, Sabine D; Becker, Simon; Wolf, Ursula

2012-01-01

Chai hu (Bupleuri radix), one of the most frequently used herbs in Chinese herbal medicine, has 3 major functions, depending on dosage and combination with other herbs. The aim of this study was to investigate how chai hu is prescribed in everyday practice in Switzerland, and whether these prescription patterns reflect its various applications. A random sample of 1,053 prescriptions was drawn from the database of Lian Chinaherb AG, Wollerau, Switzerland, and analyzed regarding the most frequently used classical formulas containing chai hu, daily dosages and combinations with other herbs. 29.0% of all prescriptions contained chai hu, and 98.0% of these were in granular form. The most frequently used classical formulas were xiao yao san ('rambling powder'), jia wei xiao yao san ('augmented rambling powder') and chai hu shu gan san ('Bupleurum powder to spread the liver'). In more than half of the prescriptions, chai hu was combined with bai shao (Paeoniae Radix Alba), dang gui (Angelicae sinensis radix) or fu ling (Poria). 51.8% of the prescriptions contained a low daily dosage of chai hu, 24.9% a medium and 15.1% a high dosage. Chai hu was generally prescribed in classic combinations with other herbs and in a medium dosage. Due to the addition of supplementary herbs to classical formulas, its daily dose was often diminished from a high or medium dose to a low dose. This raises the question if chai hu would then still exert its desired function of, e.g., moving liver-qi in these prescriptions.

Characterizing T Cells in SCID Patients Presenting with Reactive or Residual T Lymphocytes

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Atar Lev

2012-01-01

Full Text Available Introduction. Patients with severe combined immunodeficiency (SCID may present with residual circulating T cells. While all cells are functionally deficient, resulting in high susceptibility to infections, only some of these cells are causing autoimmune symptoms. Methods. Here we compared T-cell functions including the number of circulating CD3+ T cells, in vitro responses to mitogens, T-cell receptor (TCR repertoire, TCR excision circles (TREC levels, and regulatory T cells (Tregs enumeration in several immunodeficinecy subtypes, clinically presenting with nonreactive residual cells (MHC-II deficiency or reactive cells. The latter includes patients with autoreactive clonal expanded T cell and patients with alloreactive transplacentally maternal T cells. Results. MHC-II deficient patients had slightly reduced T-cell function, normal TRECs, TCR repertoires, and normal Tregs enumeration. In contrast, patients with reactive T cells exhibited poor T-cell differentiation and activity. While the autoreactive cells displayed significantly reduced Tregs numbers, the alloreactive transplacentally acquired maternal lymphocytes had high functional Tregs. Conclusion. SCID patients presenting with circulating T cells show different patterns of T-cell activity and regulatory T cells enumeration that dictates the immunodeficient and autoimmune manifestations. We suggest that a high-tolerance capacity of the alloreactive transplacentally acquired maternal lymphocytes represents a toleration advantage, yet still associated with severe immunodeficiency.

An experimental study of mechanism in treatment for endometriosis with Xiao Chai Hu Tang in rats

International Nuclear Information System (INIS)

Zhang Hui; Zuo Liandong; Li Hongyi

2005-01-01

To explore the mechanism of Xiao Chai Hu Tang in treatment for endometriosis in rats, the rat model of endometriosis was established. Using immunohistochemistry method, Fas and Caspase-3 protein expression in endometrium and endometriotic tissue of each group were observed. The results showed that in the group treated with Xiao Chai Hu Tang, the protein expressions of Fas and Caspase-3 in endometriotic tissue were higher than those in endometrium, while in the control group, the result was just opposite. The difference was not obvious in the group treated with Danazol . The higher levels of the protein expression of Fas in endometriotic tissue may related to the pathogenesis of the endometriosis. The mechanism of Xiao Chai Hu Tang treatment may be partly to increase apoptosis in endometriotic tissue. (authors)

[The good PBL tutor--to be or not to be: instructional films for tutors].

Science.gov (United States)

Skelin, Silvia; Huwendiek, Sören; Nikendei, Christoph; Dieter, Peter; Kirschfink, Michael; Bosse, Hans-Martin

2008-01-01

Many faculties worldwide apply the method of problem-based learning (PBL) in their curricula as a form of instruction by which students in small groups develop problem-solving strategies on the basis of a specific case. This approach fosters self-responsible and context-dependent learning, which aims at providing an improved anchoring of knowledge. For this reason, the previous decades have seen a distribution of the method to medical schools across the world. The role of the tutor assumes particular importance since, in contrast to the traditional university system, he or she serves as a facilitator who fosters and structures content-related and group-dynamic learning processes. In some cases, this requires an intervention by the tutor. The major challenge is to intervene at the right time and in an appropriate manner. This paper presents examples of difficult PBL situations using short film sequences to demonstrate and comments on potential approaches of the tutor in attempting to resolve the problem. Standard problem situations within a PBL tutorial were defined and produced in a film. A collection of seven frequent critical PBL situations are presented in short film sequences. Potential instruments of intervention are demonstrated in the videos and discussed. The film sequences may be downloaded in the supplementary of the electronic version of this article (www.sciencedirect.com). Within the framework of a tutor-training programme, the problematic situations and interventions presented in this article will help to sensitise tutors to potentially critical PBL tutorial situations and aid the development of individual resolution approaches.

Choices Outlined 2013-2017. An analysis of ten election programmes for accessibility effects. PBL-CPB background document; Keuzes in kaart 2013-2017. Een analyse van tien verkiezingsprogramma's op bereikbaarheidseffecten. PBL-CPB Achtergronddocument

Energy Technology Data Exchange (ETDEWEB)

Zwaneveld, P.; Verrips, A. [CPB Netherlands Bureau for Economic Policy Analysis, The Hague (Netherlands); Hilbers, H.; Zondag, B.; Van Meerkerk, J. [Planbureau voor de Leefomgeving PBL, Den Haag (Netherlands); Weijschede-van der Straaten, W. [CBS Statistics Netherlands, The Hague (Netherlands)

2012-11-15

In their report 'Keuzes in Kaart 2013-2017' (Choices outlined 2013-2017) the Netherlands Bureau for Economic Policy Analysis (CPB) and the Environmental Assessment Agency (PBL) made calculations for thirteen themes of the election programs of ten Dutch political parties. Accessibility is one of these thirteen themes. Analyses on this theme were conducted jointly by PBL and CPB. This paper addresses which different political choices the Dutch parties have made for the theme of accessibility, how PBL and CPB conducted analyses and which results were yielded. The effect of the party program is compared to a basic path, the expected image for 2020 based on implementation of the Budget Agreement 2013 ('Spring Agreement'). [Dutch] Het Centraal Planbureau (CPB) en het Planbureau voor de Leefomgeving (PBL) hebben in het rapport 'Keuzes in Kaart 2013-2017' de verkiezingsprogramma's van tien politieke partijen doorgerekend op dertien thema's. Bereikbaarheid is één van de dertien thema's. De analyses rond dit thema zijn gezamenlijk uitgevoerd door PBL en CPB. Dit paper gaat in op welke verschillende politieke keuzes de partijen ten aanzien van bereikbaarheid hebben gemaakt, op welke wijze de planbureaus dit hebben geanalyseerd en tot welke resultaten dit heeft geleid. Het effect van het partijprogramma wordt vergeleken met het 'basispad', het verwachte beeld voor 2020 uitgaande van uitvoering van het Begrotingsakkoord 2013 (het 'Lenteakkoord')

Pengembangan Critical Thinking melalui Penerapan Model PBL (Problem Based Learning) dalam Pembelajaran Sains

OpenAIRE

Widowati, Asri

2010-01-01

This paper examines to explore how study by using model of Problem Based Learning ( PBL). Basically, this discussion is focussed at model of PBL as an effort in developing cognitive ability, especially critical thinking.Critical thinking including ability think high level (higher order of thinking) representing one of the component in issue intellegence of 21 st century ( Issue of The 21st literacy century). Development of ability of critical thinking in study of science of vital importance b...

Subunit-specific phenotypes of Salmonella typhimurium HU mutants.

OpenAIRE

Hillyard, D R; Edlund, M; Hughes, K T; Marsh, M; Higgins, N P

1990-01-01

Salmonella hupA and hupB mutants were studied to determine the reasons for the high degree of conservation in HU structure in bacteria. We found one HU-1-specific effect; the F'128 plasmid was 25-fold less stable in hupB compared with hupA or wild-type cells. F' plasmids were 120-fold more unstable in hupA hupB double mutants compared with wild-type cells, and the double mutant also had a significant alteration in plasmid DNA structure. pBR322 DNA isolated from hupA hupB strains was deficient...

Heterozygous Che-1 KO mice show deficiencies in object recognition memory persistence.

Science.gov (United States)

Zalcman, Gisela; Corbi, Nicoletta; Di Certo, Maria Grazia; Mattei, Elisabetta; Federman, Noel; Romano, Arturo

2016-10-06

Transcriptional regulation is a key process in the formation of long-term memories. Che-1 is a protein involved in the regulation of gene transcription that has recently been proved to bind the transcription factor NF-κB, which is known to be involved in many memory-related molecular events. This evidence prompted us to investigate the putative role of Che-1 in memory processes. For this study we newly generated a line of Che-1(+/-) heterozygous mice. Che-1 homozygous KO mouse is lethal during development, but Che-1(+/-) heterozygous mouse is normal in its general anatomical and physiological characteristics. We analyzed the behavioral characteristic and memory performance of Che-1(+/-) mice in two NF-κB dependent types of memory. We found that Che-1(+/-) mice show similar locomotor activity and thigmotactic behavior than wild type (WT) mice in an open field. In a similar way, no differences were found in anxiety-like behavior between Che-1(+/-) and WT mice in an elevated plus maze as well as in fear response in a contextual fear conditioning (CFC) and object exploration in a novel object recognition (NOR) task. No differences were found between WT and Che-1(+/-) mice performance in CFC training and when tested at 24h or 7days after training. Similar performance was found between groups in NOR task, both in training and 24h testing performance. However, we found that object recognition memory persistence at 7days was impaired in Che-1(+/-) heterozygous mice. This is the first evidence showing that Che-1 is involved in memory processes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Maternal influence on susceptibility of offspring to Brugia malayi infection in a murine model of filariasis.

Science.gov (United States)

Rajan, T V; Bailis, J M; Yates, J A; Shultz, L D; Greiner, D L; Nelson, F K

1994-12-01

We have used the severe combined immunodeficient C.B-17-scid/scid mouse to investigate the influences of maternal immune status and parasite burden on the susceptibility (or resistance) of offspring to infection with the human filarial parasite, Brugia malayi. C.B-17-scid/scid mice are permissive for infection while immunocompetent C.B-17(-)+/+ mice are uniformly resistant. Reciprocal matings of C.B-17-scid/scid and C.B-17(-)+/+ mice were performed. The C.B-17-scid/scid females were either naive or infected with Brugia malayi. The resulting immunocompetent C.B-17-scid/+ and C.B-17(-)+/scid progeny were challenged at weaning with an intraperitoneal injection of Brugia malayi third stage larvae known to produce patent infection in > 95% of C.B-17-scid/scid mice. We observed that 40.0%l (34/85) of the immunocompetent offspring of C.B-17-scid/scid females x C.B-17(-)+/+ males were permissive for the growth and development of Brugia malayi larvae to adults. No difference was observed in susceptibility to infection between the progeny of infected or uninfected C.B-17-scid/scid mothers mated with C.B-17(-)+/+ fathers, arguing against acquired immunological tolerance to the parasite in the former. In marked contrast, only 4.8% (2/42) of the heterozygous progeny of wild type C.B-17(-)+/+ females mated with C.B-17-scid/scid males were permissive. These observations document conversion of a 'resistant' phenotype to a 'susceptible' phenotype by manipulation of maternal immune status and provide clear evidence of maternal influence on offspring susceptibility to infection with Brugia malayi.

89Zr-huJ591 immuno-PET imaging in patients with advanced metastatic prostate cancer

International Nuclear Information System (INIS)

Pandit-Taskar, Neeta; Solomon, Stephen B.; Durack, Jeremy C.; Carrasquillo, Jorge A.; Lefkowitz, Robert A.; Osborne, Joseph R.; O'Donoghue, Joseph A.; Beylergil, Volkan; Ruan, Shutian; Cheal, Sarah M.; Lyashchenko, Serge; Gonen, Mithat; Lewis, Jason S.; Holland, Jason P.; Reuter, Victor E.; Loda, Massimo F.; Smith-Jones, Peter M.; Weber, Wolfgang A.; Larson, Steven M.; Bander, Neil H.; Scher, Howard I.; Morris, Michael J.

2014-01-01

conventional imaging modality was negative. 89 Zr-huJ591 PET imaging of prostate-specific membrane antigen expression is safe and shows good localization of disease in prostate cancer patients. Liver is the critical organ for dosimetry, and 7 ± 1 days is the optimal imaging time. A larger study is underway to determine lesion detection in an expanded cohort of patients with metastatic prostate cancer. (orig.)

Health related quality of life and mental health in children with SCI/D from Neiva, Colombia.

Science.gov (United States)

Leibach, Gillian G; Perrin, Paul B; Nicholls, Elizabeth; Leonor Olivera, Silvia; Medina Quintero, Lorena; Mauricio Velasco Trujillo, Diego; Carlos Arango-Lasprilla, Juan

2015-01-01

To date, no research has been published on the health related quality of life (HRQOL) and mental health of children with spinal cord injury and disorders (SCI/D) in Latin America, although limited previous research in Western countries has demonstrated the debilitating and chronic nature of these conditions in children. The aim was to examine the connections between HRQOL and mental health in children with SCI/D from Neiva, Colombia. Thirty children (8- 17 years) were recruited from the Hospital Universatario Hernando Mocaleano Perdomo in Neiva, Colombia. Participants completed self-report measures administered verbally by trained research staff. A correlation matrix generally suggested that higher HRQOL was robustly associated with better mental health. A series of multiple regressions found that HRQOL explained 50.5% of the variance in children's depression, 31.5% of the variance in worry, and 41.9% of the variance in social anxiety. Within these regressions, emotional and social functioning were uniquely associated with depression, and emotional functioning was uniquely associated with social anxiety. This is the first published study to examine psychosocial outcomes in children with SCI/D in Latin America, and its findings suggest that future research and interventions for children with SCI/D in Colombia - and possibly in other regions of Latin America - would benefit from emphasizing emotional and social functioning.

Characteristic scapular and rib changes on chest radiographs of children with ADA-deficiency SCIDS in the first year of life.

Science.gov (United States)

Manson, David; Diamond, Lauren; Oudjhane, Kamaldine; Hussain, Faisal Bin; Roifman, Chaim; Grunebaum, Eyal

2013-03-01

We describe radiographic changes in the ribs and scapulae seen in the first 6 months of life in children with ADA (adenosine deaminase) deficiency severe combined immundeficiency syndrome (SCIDS). We suggest that these changes are reversible with appropriate enzyme replacement therapy. The purpose of this study was to describe characteristic rib and scapular radiographic changes in infants with ADA-deficiency SCIDS. This was a retrospective review of chest radiographs of nine children with ADA-deficiency SCIDS performed in the first year of life by two experienced pediatric radiologists. A control cohort of unaffected children was used for comparison. All children with ADA-deficiency SCIDS manifested unusual scapular spurring and anterior rib cupping. None of the control children manifested these changes. Characteristic and reversible scapular and rib changes in the correct clinical setting should suggest an early diagnosis of ADA deficiency, prompting appropriate diagnostic and therapeutic measures.

HuMOVE: a low-invasive wearable monitoring platform in sexual medicine.

Science.gov (United States)

Ciuti, Gastone; Nardi, Matteo; Valdastri, Pietro; Menciassi, Arianna; Basile Fasolo, Ciro; Dario, Paolo

2014-10-01

To investigate an accelerometer-based wearable system, named Human Movement (HuMOVE) platform, designed to enable quantitative and continuous measurement of sexual performance with minimal invasiveness and inconvenience for users. Design, implementation, and development of HuMOVE, a wearable platform equipped with an accelerometer sensor for monitoring inertial parameters for sexual performance assessment and diagnosis, were performed. The system enables quantitative measurement of movement parameters during sexual intercourse, meeting the requirements of wearability, data storage, sampling rate, and interfacing methods, which are fundamental for human sexual intercourse performance analysis. HuMOVE was validated through characterization using a controlled experimental test bench and evaluated in a human model during simulated sexual intercourse conditions. HuMOVE demonstrated to be a robust and quantitative monitoring platform and a reliable candidate for sexual performance evaluation and diagnosis. Characterization analysis on the controlled experimental test bench demonstrated an accurate correlation between the HuMOVE system and data from a reference displacement sensor. Experimental tests in the human model during simulated intercourse conditions confirmed the accuracy of the sexual performance evaluation platform and the effectiveness of the selected and derived parameters. The obtained outcomes also established the project expectations in terms of usability and comfort, evidenced by the questionnaires that highlighted the low invasiveness and acceptance of the device. To the best of our knowledge, HuMOVE platform is the first device for human sexual performance analysis compatible with sexual intercourse; the system has the potential to be a helpful tool for physicians to accurately classify sexual disorders, such as premature or delayed ejaculation. Copyright © 2014 Elsevier Inc. All rights reserved.

Heterologous human/rat HER2-specific exosome-targeted T cell vaccine stimulates potent humoral and CTL responses leading to enhanced circumvention of HER2 tolerance in double transgenic HLA-A2/HER2 mice.

Science.gov (United States)

Xie, Yufeng; Wu, Jie; Xu, Aizhang; Ahmeqd, Shahid; Sami, Amer; Chibbar, Rajni; Freywald, Andrew; Zheng, Changyu; Xiang, Jim

2018-03-07

DNA vaccines composed of heterologous human HER2 and rat neu sequences induce stronger antibody response and protective antitumor immunity than either HER2 or neu DNA vaccines in transgenic mice. We previously developed HER2-specific exosome-targeted T-cell vaccine HER2-T EXO capable of stimulating HER2-specific CD8 + T-cell responses, but only leading to partial protective immunity in double-transgenic HLA-A2/HER2 mice with self-immune tolerance to HER2. Here, we constructed an adenoviral vector AdV HuRt expressing HuRt fusion protein composed of NH 2 -HER2 1-407 (Hu) and COOH-neu 408-690 (Rt) fragments, and developed a heterologous human/rat HER2-specific exosome-targeted T-cell vaccine HuRt-T EXO using polyclonal CD4 + T-cells uptaking exosomes released by AdV HuRt -transfected dendritic cells. We found that the HuRt-T EXO vaccine stimulates enhanced CD4 + T-cell responses leading to increased induction of HER2-specific antibody (∼70 µg/ml) compared to that (∼40 µg/ml) triggered by the homologous HER2-T EXO vaccine. By using PE-H-2K d /HER2 23-71 tetramer, we determined that HuRt-T EXO stimulates stronger HER2-specific CD8 + T-cell responses eradicating 90% of HER2-specific target cells, while HER2-T EXO -induced CD8 + T-cell responses only eliminating 53% targets. Furthermore, HuRt-T EXO , but not HER2-T EXO vaccination, is capable of suppressing early stage-established HER2-expressing 4T1 HER2 breast cancer in its lung metastasis or subcutaneous form in BALB/c mice, and of completely protecting transgenic HLA-A2/HER2 mice from growth of HLA-A2/HER2-expressing BL6-10 A2/HER2 melanoma. HuRt-T EXO -stimulated HER2-specific CD8 + T-cells not only are cytolytic to trastuzumab-resistant HLA-A2/HER2-expressing BT474/A2 breast tumor cells in vitro but also eradicates pre-established BT474/A2 tumors in athymic nude mice. Therefore, our novel heterologous human/rat HER2-specific T-cell vaccine HuRt-T EXO, circumventing HER2 tolerance, may provide a new

Subjective and Objective Evaluation of PBL Outcomes in Preclinical ...

African Journals Online (AJOL)

Subjective and Objective Evaluation of PBL Outcomes in Preclinical Medical Students. ... ABSTRACT: Problem based learning curriculum is widely recognized as a progressive, learner-centered, active learning approach and is currently used in the entire medical curriculum in over 10% of medical schools worldwide.

Infestivity of Demodex canis to hamster skin engrafted onto SCID mice.

Science.gov (United States)

Tani, Kenji; Une, Satoshi; Hasegawa, Atsuhiko; Adachi, Makoto; Kanda, Naoko; Watanabe, Shin-ichi; Nakaichi, Munekazu; Taura, Yasuho

2005-04-01

We demonstrated that Demodex canis was transferred to skin xenografts of a dog and a hamster onto severe combined immunodeficiency mice. After the transfer of mites, the number of eggs, larvae, nymphs and adult mites per gram of canine and hamster xenografts increased, whereas no live mites were detected on murine allograft. These results indicate that D. canis proliferates in hair follicles of dog and hamster skins but not in murine allograft. Therefore, D. canis may have host preference but not strict host-specificity.

WE-AB-202-06: Correlating Lung CT HU with Transformation-Based and Xe-CT Derived Ventilation

International Nuclear Information System (INIS)

Du, K; Patton, T; Bayouth, J; Reinhardt, J; Christensen, G

2016-01-01

Purpose: Regional lung ventilation is useful to reduce radiation-induced function damage during lung cancer radiation therapy. Recently a new direct HU (Hounsfield unit)-based method was proposed to estimate the ventilation potential without image registration. The purpose of this study is to examine if there is a functional dependence between HU values and transformation-based or Xe-CT derived ventilation. Methods: 4DCT images acquired from 13 patients prior to radiation therapy and 4 mechanically ventilated sheep subjects which also have associated Xe-CT images were used for this analysis. Transformation-based ventilation was computed using Jacobian determinant of the transformation field between peak-exhale and peak-inhale 4DCT images. Both transformation and Xe-CT derived ventilation was computed for each HU bin. Color scatter plot and cumulative histogram were used to compare and validate the direct HU-based method. Results: There was little change of the center and shape of the HU histograms between free breathing CT and 4DCT average, with or without smoothing, and between the repeated 4DCT scans. HU of −750 and −630 were found to have the greatest transformation-based ventilation for human and sheep subjects, respectively. Maximum Xe-CT derived ventilation was found to locate at HU of −600 in sheep subjects. The curve between Xe-CT ventilation and HU was noisy for tissue above HU −400, possibly due to less intensity change of Xe gas during wash-out and wash-in phases. Conclusion: Both transformation-based and Xe-CT ventilation demonstrated that lung tissues with HU values in the range of (-750, −600) HU have the maximum ventilation potential. The correlation between HU and ventilation suggests that HU might be used to help guide the ventilation calculation and make it more robust to noise and image registration errors. Research support from NIH grants CA166703 and CA166119 and a gift from Roger Koch.

WE-AB-202-06: Correlating Lung CT HU with Transformation-Based and Xe-CT Derived Ventilation

Energy Technology Data Exchange (ETDEWEB)

Du, K; Patton, T; Bayouth, J [University of Wisconsin, Madison, WI (United States); Reinhardt, J; Christensen, G [The University of Iowa, Iowa City, IA (United States)

2016-06-15

Purpose: Regional lung ventilation is useful to reduce radiation-induced function damage during lung cancer radiation therapy. Recently a new direct HU (Hounsfield unit)-based method was proposed to estimate the ventilation potential without image registration. The purpose of this study is to examine if there is a functional dependence between HU values and transformation-based or Xe-CT derived ventilation. Methods: 4DCT images acquired from 13 patients prior to radiation therapy and 4 mechanically ventilated sheep subjects which also have associated Xe-CT images were used for this analysis. Transformation-based ventilation was computed using Jacobian determinant of the transformation field between peak-exhale and peak-inhale 4DCT images. Both transformation and Xe-CT derived ventilation was computed for each HU bin. Color scatter plot and cumulative histogram were used to compare and validate the direct HU-based method. Results: There was little change of the center and shape of the HU histograms between free breathing CT and 4DCT average, with or without smoothing, and between the repeated 4DCT scans. HU of −750 and −630 were found to have the greatest transformation-based ventilation for human and sheep subjects, respectively. Maximum Xe-CT derived ventilation was found to locate at HU of −600 in sheep subjects. The curve between Xe-CT ventilation and HU was noisy for tissue above HU −400, possibly due to less intensity change of Xe gas during wash-out and wash-in phases. Conclusion: Both transformation-based and Xe-CT ventilation demonstrated that lung tissues with HU values in the range of (-750, −600) HU have the maximum ventilation potential. The correlation between HU and ventilation suggests that HU might be used to help guide the ventilation calculation and make it more robust to noise and image registration errors. Research support from NIH grants CA166703 and CA166119 and a gift from Roger Koch.

Are deep strategic learners better suited to PBL? A preliminary study.

Science.gov (United States)

Papinczak, Tracey

2009-08-01

The aim of this study was to determine if medical students categorized as having deep and strategic approaches to their learning find problem-based learning (PBL) enjoyable and supportive of their learning, and achieve well in the first-year course. Quantitative and qualitative data were gathered from first-year medical students (N = 213). All students completed the Medical Course Learning Questionnaire at the commencement and completion of their first year of medical studies. The instrument measured a number of different aspects of learning, including approaches to learning, preferences for different learning environments, self-efficacy, and perceptions of learning within PBL tutorials. Qualitative data were collected from written responses to open questions. Results of students' performance on two forms of examinations were obtained for those giving permission (N = 68). Two-step cluster analysis of the cohort's responses to questions about their learning approaches identified five clusters, three of which represented coherent combinations of learning approaches (deep, deep and strategic, and surface apathetic) and two clusters which had unusual or dissonant combinations. Deep, strategic learners represented 25.8% of the cohort. They were more efficacious, preferred learning environments which support development of understanding and achieved significantly higher scores on the written examination. Strongly positive comments about learning in PBL tutorials were principally described by members of this cluster. This preliminary study employed a technique to categorize a student cohort into subgroups on the basis of their approaches to learning. One, the deep and strategic learners, appeared to be less vulnerable to the stresses of PBS in a medical course. While variation between individual learners will always be considerable, this analysis has enabled classification of a student group that may be less likely to find PBL problematic. Implications for practice and

MODELAGEM DE UM SISTEMA MULTIAGENTE DE APOIO À PBL UTILIZANDO A METODOLOGIA MAS-COMMONKADS+

Directory of Open Access Journals (Sweden)

Laysa Mabel de Oliveira Fontes

2014-10-01

Full Text Available A aprendizagem baseada em problema (Problem-Based Learning - PBL é um método no qual os estudantes aprendem através da resolução de um problema que, em geral, não possui uma solução trivial e uma única solução correta. A PBL destaca o trabalho em equipe como um dos principais requisitos para o sucesso do processo de aprendizagem, ou seja, a colaboração é essencial. No entanto, a implantação de um método de ensino com base na PBL não é uma tarefa trivial. Em Ambientes Virtuais de Aprendizagem (AVAs, a complexidade de implantação deste método é ainda maior, pois o facilitador nem sempre pode detectar possíveis problemas na colaboração, nem possui todas as informações necessárias para aplicar as técnicas de aprendizagem deste método. Desta forma, este artigo apresenta o processo de modelagem de um Sistema Multiagente (SMA de apoio à PBL. O SMA proposto foi modelado utilizando a metodologia MAS-CommonKADS+, que consiste em uma extensão da metodologia MAS-CommonKADS.

Hu on poolel teel / James Miles

Index Scriptorium Estoniae

Miles, James

2006-01-01

2007. aastal toimuv kommunistliku partei 17. kongress tähistab Hiina presidendi Hu Jintao jaoks oma võimuaja poole peale jõudmist, ees ootavad sellised väljakutsed nagu olümpiamängude korraldamine, valimiskeeris Taiwanis ning hullunud majanduse stabiliseerimine. Vt samas: Hiina avanemise pidu

PROJECT BASED LEARNING (PBL TO IMPROVE PSYCHOMOTORIC SKILLS: A CLASSROOM ACTION RESEARCH

Directory of Open Access Journals (Sweden)

W. Sumarni

2016-10-01

Full Text Available This paper discusses the application of project-based learning (PBL to improve student’ psychomotor skills and concept understanding, as well as knowing what PBL contribution to the improvement of student’ psychomotor skills in chemistry learning. The study was conducted in three cycles. Each cycle consisted of planning, implementation, observation, and reflection steps. One set of data consists of student’ psychomotor skills assesment, student’ conceptual understanding and questionnaire responses were obtained from the action research. Learning process was performed in the eleventh grade students included 37 students (10 males and 27 females and 3 collaborators. The successful research was indicated by 85% of students achieve the mastery learning on concept understanding and well on psychomotor aspects. Data collection was performed using documentation method by questionnaire, observations, and tests. Data was analyzed quantitatively and qualitatively. The results show that all aspects of the psychomotor assessed include sets, mechanical response, complex response, adaptation, and origination were in high category. At the end of the lesson, the project assigned to students were evaluated jointly between teachers and students. The project results in the form of a series of distillation apparatus is applied to separate the natural compounds.

Pengembangan Modul Pembelajaran Fisika Berbasis Problem Based Learning (PBL pada Materi Gelombang Bunyi untuk Siswa SMA Kelas XII

Directory of Open Access Journals (Sweden)

Tri Anita Nur Hasanah

2017-03-01

Full Text Available The 2013 curriculum emphasizes on Scientific Approach taht tie topic with real context. Either learning model that leads to Scientific Approach that is Problem Based Learning (PBL. So that need to prepare appropriate teaching material to support learning model PBL one of them module independent teaching topic for learners. The aim of these research is describe the Learning Module which is developed that is physic learning module based on PBL of the topic sound wave for senior high school grade XII and examine its feasibility. This development research used 4-D Thiagarajan with modified model. This research has been done in three stages such as define, design, and develop which are restricted until the limited try out. The data collection is used questionnaire. The module validation by 4 validators and limited try out to 10 students. The result of research drawn that material aspect is 3,59 with the suitable criterion, presentation aspect is 3,9 with the suitable criterion, language aspect is 3,41 with the suitable criterion, and the limited try out result got 3,6 with an appropriate criterion. In conclusion, physic learning module based on PBL in sound wave material for senior high school grade XII is applicable. Keywords: Physic Learning Module, Problem Based Learning (PBL, Topic sound wave Pada kurikulum 2013 menekankan pada Scientific Approach yang mengaitkan materi dengan konteks dunia nyata. Salah satu model pembelajaran yang mengarah ke Scientific Approach yaitu Problem Based Learning (PBL. Sehingga perlu dipersiapkan bahan ajar yang tepat untuk mendukung model pembelajaran PBL salah satunya modul yang merupakan bahan ajar mandiri bagi peserta didik. Tujuan penelitian ini adalah mendeskripsikan pengembangan modul yaitu modul pembelajaran fisika berbasis PBL pada materi Gelombang Bunyi untuk siswa SMA kelas XII dan menguji kelayakannya.Penelitian pengembangan menggunakan model 4-D Thiagarajan yang sudah di modifikasi. Penelitian ini

A murine model of falciparum-malaria by in vivo selection of competent strains in non-myelodepleted mice engrafted with human erythrocytes.

Directory of Open Access Journals (Sweden)

Iñigo Angulo-Barturen

Full Text Available To counter the global threat caused by Plasmodium falciparum malaria, new drugs and vaccines are urgently needed. However, there are no practical animal models because P. falciparum infects human erythrocytes almost exclusively. Here we describe a reliable falciparum murine model of malaria by generating strains of P. falciparum in vivo that can infect immunodeficient mice engrafted with human erythrocytes. We infected NOD(scid/beta2m-/- mice engrafted with human erythrocytes with P. falciparum obtained from in vitro cultures. After apparent clearance, we obtained isolates of P. falciparum able to grow in peripheral blood of engrafted NOD(scid/beta2m-/- mice. Of the isolates obtained, we expanded in vivo and established the isolate Pf3D7(0087/N9 as a reference strain for model development. Pf3D7(0087/N9 caused productive persistent infections in 100% of engrafted mice infected intravenously. The infection caused a relative anemia due to selective elimination of human erythrocytes by a mechanism dependent on parasite density in peripheral blood. Using this model, we implemented and validated a reproducible assay of antimalarial activity useful for drug discovery. Thus, our results demonstrate that P. falciparum contains clones able to grow reproducibly in mice engrafted with human erythrocytes without the use of myeloablative methods.

Nanosystems based on siRNA silencing HuR expression counteract diabetic retinopathy in rat.

Science.gov (United States)

Amadio, Marialaura; Pascale, Alessia; Cupri, Sarha; Pignatello, Rosario; Osera, Cecilia; D Agata, Velia; D Amico, Agata Grazia; Leggio, Gian Marco; Ruozi, Barbara; Govoni, Stefano; Drago, Filippo; Bucolo, Claudio

2016-09-01

We evaluated whether specifically and directly targeting human antigen R (HuR), a member of embryonic lethal abnormal vision (ELAV) proteins family, may represent a new potential therapeutic strategy to manage diabetic retinopathy. Nanosystems loaded with siRNA silencing HuR expression (lipoplexes), consisting of solid lipid nanoparticles (SLN) and liposomes (SUV) were prepared. Photon correlation spectroscopy analysis, Zeta potential measurement and atomic force microscopy (AFM) studies were carried out to characterize the complexation of siRNA with the lipid nanocarriers. Nanosystems were evaluated by using AFM and scanning electron microscopy. The lipoplexes were injected into the eye of streptozotocin (STZ)-induced diabetic rats. Retinal HuR and VEGF levels were detected by Western blot and ELISA, respectively. Retinal histology was also carried out. The results demonstrated that retinal HuR and VEGF are significantly increased in STZ-rats and are blunted by HuR siRNA treatment. Lipoplexes with a weak positive surface charge and with a 4:1 N/P (cationic lipid nitrogen to siRNA phosphate) ratio exert a better transfection efficiency, significantly dumping retinal HuR and VEGF levels. In conclusion, we demonstrated that siRNA can be efficiently delivered into the rat retina using lipid-based nanocarriers, and some of the lipoplexes loaded with siRNA silencing HuR expression are potential candidates to manage retinal diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

Merging research orientation with professional apprenticeship training through PBL

DEFF Research Database (Denmark)

Willert, Søren

2012-01-01

The paper discusses an ongoing process of merging two university-based teaching traditions. The two traditions are alike in that both share a basic commitment to PBL-related values. Differences refer (as stated in the paper’s title) to one tradition being relatively more research oriented, whereas...

Clinical utility of the DSM-5 alternative model for borderline personality disorder: Differential diagnostic accuracy of the BFI, SCID-II-PQ, and PID-5.

Science.gov (United States)

Fowler, J Christopher; Madan, Alok; Allen, Jon G; Patriquin, Michelle; Sharp, Carla; Oldham, John M; Frueh, B Christopher

2018-01-01

With the publication of DSM 5 alternative model for personality disorders it is critical to assess the components of the model against evidence-based models such as the five factor model and the DSM-IV-TR categorical model. This study explored the relative clinical utility of these models in screening for borderline personality disorder (BPD). Receiver operator characteristics and diagnostic efficiency statistics were calculated for three personality measures to ascertain the relative diagnostic efficiency of each measure. A total of 1653 adult inpatients at a specialist psychiatric hospital completed SCID-II interviews. Sample 1 (n=653) completed the SCID-II interviews, SCID-II Questionnaire (SCID-II-PQ) and the Big Five Inventory (BFI), while Sample 2 (n=1,000) completed the SCID-II interviews, Personality Inventory for DSM5 (PID-5) and the BFI. BFI measure evidenced moderate accuracy for two composites: High Neuroticism+ low agreeableness composite (AUC=0.72, SE=0.01, ptrait constellation for diagnosing BPD. Limitations of the study include the single inpatient setting and use of two discrete samples to assess PID-5 and SCID-II-PQ. Copyright © 2017 Elsevier Inc. All rights reserved.

Evolution to pathogenicity of the parvovirus minute virus of mice in immunodeficient mice involves genetic heterogeneity at the capsid domain that determines tropism.

Science.gov (United States)

López-Bueno, Alberto; Segovia, José C; Bueren, Juan A; O'Sullivan, M Gerard; Wang, Feng; Tattersall, Peter; Almendral, José M

2008-02-01

Very little is known about the role that evolutionary dynamics plays in diseases caused by mammalian DNA viruses. To address this issue in a natural host model, we compared the pathogenesis and genetics of the attenuated fibrotropic and the virulent lymphohematotropic strains of the parvovirus minute virus of mice (MVM), and of two invasive fibrotropic MVM (MVMp) variants carrying the I362S or K368R change in the VP2 major capsid protein, in the infection of severe combined immunodeficient (SCID) mice. By 14 to 18 weeks after oronasal inoculation, the I362S and K368R viruses caused lethal leukopenia characterized by tissue damage and inclusion bodies in hemopoietic organs, a pattern of disease found by 7 weeks postinfection with the lymphohematotropic MVM (MVMi) strain. The MVMp populations emerging in leukopenic mice showed consensus sequence changes in the MVMi genotype at residues G321E and A551V of VP2 in the I362S virus infections or A551V and V575A changes in the K368R virus infections, as well as a high level of genetic heterogeneity within a capsid domain at the twofold depression where these residues lay. Amino acids forming this capsid domain are important MVM tropism determinants, as exemplified by the switch in MVMi host range toward mouse fibroblasts conferred by coordinated changes of some of these residues and by the essential character of glutamate at residue 321 for maintaining MVMi tropism toward primary hemopoietic precursors. The few viruses within the spectrum of mutants from mice that maintained the respective parental 321G and 575V residues were infectious in a plaque assay, whereas the viruses with the main consensus sequences exhibited low levels of fitness in culture. Consistent with this finding, a recombinant MVMp virus carrying the consensus sequence mutations arising in the K368R virus background in mice failed to initiate infection in cell lines of different tissue origins, even though it caused rapid-course lethal leukopenia in SCID

HuD and the Survival Motor Neuron Protein Interact in Motoneurons and Are Essential for Motoneuron Development, Function, and mRNA Regulation.

Science.gov (United States)

Hao le, Thi; Duy, Phan Q; An, Min; Talbot, Jared; Iyer, Chitra C; Wolman, Marc; Beattie, Christine E

2017-11-29

Motoneurons establish a critical link between the CNS and muscles. If motoneurons do not develop correctly, they cannot form the required connections, resulting in movement defects or paralysis. Compromised development can also lead to degeneration because the motoneuron is not set up to function properly. Little is known, however, regarding the mechanisms that control vertebrate motoneuron development, particularly the later stages of axon branch and dendrite formation. The motoneuron disease spinal muscular atrophy (SMA) is caused by low levels of the survival motor neuron (SMN) protein leading to defects in vertebrate motoneuron development and synapse formation. Here we show using zebrafish as a model system that SMN interacts with the RNA binding protein (RBP) HuD in motoneurons in vivo during formation of axonal branches and dendrites. To determine the function of HuD in motoneurons, we generated zebrafish HuD mutants and found that they exhibited decreased motor axon branches, dramatically fewer dendrites, and movement defects. These same phenotypes are present in animals expressing low levels of SMN, indicating that both proteins function in motoneuron development. HuD binds and transports mRNAs and one of its target mRNAs, Gap43 , is involved in axonal outgrowth. We found that Gap43 was decreased in both HuD and SMN mutants. Importantly, transgenic expression of HuD in motoneurons of SMN mutants rescued the motoneuron defects, the movement defects, and Gap43 mRNA levels. These data support that the interaction between SMN and HuD is critical for motoneuron development and point to a role for RBPs in SMA. SIGNIFICANCE STATEMENT In zebrafish models of the motoneuron disease spinal muscular atrophy (SMA), motor axons fail to form the normal extent of axonal branches and dendrites leading to decreased motor function. SMA is caused by low levels of the survival motor neuron (SMN) protein. We show in motoneurons in vivo that SMN interacts with the RNA binding

{sup 89}Zr-huJ591 immuno-PET imaging in patients with advanced metastatic prostate cancer

Energy Technology Data Exchange (ETDEWEB)

Pandit-Taskar, Neeta; Solomon, Stephen B.; Durack, Jeremy C.; Carrasquillo, Jorge A.; Lefkowitz, Robert A.; Osborne, Joseph R. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Weill Cornell Medical College, Department of Radiology, New York, NY (United States); O' Donoghue, Joseph A. [Memorial Sloan Kettering Cancer Center, Department of Medical Physics, New York, NY (United States); Beylergil, Volkan; Ruan, Shutian; Cheal, Sarah M. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Lyashchenko, Serge [Memorial Sloan Kettering Cancer Center, Department of Radiochemistry and Molecular Imaging Probes Core, New York, NY (United States); Gonen, Mithat [Memorial Sloan Kettering Cancer Center, Department of Epidemiology and Biostatistics, New York, NY (United States); Lewis, Jason S. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Memorial Sloan Kettering Cancer Center, Department of Radiochemistry and Molecular Imaging Probes Core, New York, NY (United States); Memorial Sloan Kettering Cancer Center, Program in Molecular Pharmacology and Chemistry, New York, NY (United States); Weill Cornell Medical College, Department of Radiology, New York, NY (United States); Holland, Jason P. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Harvard Medical School, Department of Radiology of Massachusetts General Hospital, Boston, MA (United States); Reuter, Victor E. [Memorial Sloan Kettering Cancer Center, Department of Pathology, New York, NY (United States); Weill Cornell Medical College, Department of Pathology, New York, NY (United States); Loda, Massimo F. [Dana-Farber Cancer Institute, Boston, MA (United States); Broad Institute of Harvard and MIT, Cambridge, MA (United States); Smith-Jones, Peter M. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Department of Psychiatry and Behavioral Science of Stony Brook University, Stony Brook, NY (United States); Weber, Wolfgang A.; Larson, Steven M. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Memorial Sloan Kettering Cancer Center, Program in Molecular Pharmacology and Chemistry, New York, NY (United States); Weill Cornell Medical College, Department of Radiology, New York, NY (United States); Bander, Neil H. [Memorial Sloan Kettering Cancer Center, Department of Surgery, New York, NY (United States); Weill Cornell Medical College, Department of Urology, New York, NY (United States); Scher, Howard I.; Morris, Michael J. [Memorial Sloan Kettering Cancer Center, Department of Medicine, New York, NY (United States); Weill Cornell Medical College, Department of Medicine, New York, NY (United States)

2014-11-15

{sup 89}Zr-huJ591 study, while the conventional imaging modality was negative. {sup 89}Zr-huJ591 PET imaging of prostate-specific membrane antigen expression is safe and shows good localization of disease in prostate cancer patients. Liver is the critical organ for dosimetry, and 7 ± 1 days is the optimal imaging time. A larger study is underway to determine lesion detection in an expanded cohort of patients with metastatic prostate cancer. (orig.)

Apolipoprotein E-knockout mice on high-fat diet show autoimmune injury on kidney and aorta

Energy Technology Data Exchange (ETDEWEB)

Wang, Yuehai [Cardiovascular Department, Liaocheng People’s Hospital of Shandong University, Liaocheng, Shandong 252000 (China); Cardiovascular Department, The Second Clinical Medical College of Fujian Medical University, Quanzhou, Fujian 362000 (China); Lu, Huixia [The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Shandong University Qilu Hospital, Jinan, Shandong 250012 (China); Huang, Ziyang, E-mail: huangziyang666@126.com [Cardiovascular Department, The Second Clinical Medical College of Fujian Medical University, Quanzhou, Fujian 362000 (China); Lin, Huili [Cardiovascular Department, The Second Clinical Medical College of Fujian Medical University, Quanzhou, Fujian 362000 (China); Lei, Zhenmin [Department of OB/GYN, University of Louisville School of Medicine, Louisville, KY 40292 (United States); Chen, Xiaoqing [Department of Rheumatism and Immunology, The Second Clinical Medical College of Fujian Medical University, Quanzhou, Fujian 362000 (China); Tang, Mengxiong; Gao, Fei; Dong, Mei [The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Shandong University Qilu Hospital, Jinan, Shandong 250012 (China); Li, Rongda [Department of Rheumatism and Immunology, The Second Clinical Medical College of Fujian Medical University, Quanzhou, Fujian 362000 (China); Lin, Ling, E-mail: qzlinl@163.com [Department of Rheumatism and Immunology, The Second Clinical Medical College of Fujian Medical University, Quanzhou, Fujian 362000 (China)

2014-07-18

Highlights: • Titers of ANA and anti-dsDNA antibodies were similar in ApoE{sup −/−} and Fas{sup −/−} mice. • The spleen weights and glomerular areas were similar in ApoE{sup −/−} and Fas{sup −/−} mice. • Expressions of IgG and C3 in glomeruli were similar in ApoE{sup −/−} and Fas{sup −/−} mice. • IgG, C3 and macrophage infiltration in aortic plaques were found in ApoE{sup −/−} mice. - Abstract: Background: Apolipoprotein E-knockout (ApoE{sup −/−}) mice is a classic model of atherosclerosis. We have found that ApoE{sup −/−} mice showed splenomegaly, higher titers of serum anti-nuclear antibody (ANA) and anti-dsDNA antibody compared with C57B6/L (B6) mice. However, whether ApoE{sup −/−} mice show autoimmune injury remains unclear. Methods and results: Six females and six males in each group, ApoE{sup −/−}, Fas{sup −/−} and B6 mice, were used in this study. The titers of serum ANA, anti-dsDNA antibody and creatinine and urine protein were measured by ELISA after 4 months of high-fat diet. The spleen weight and the glomerular area were determined. The expressions of IgG, C3 and macrophage in kidney and atherosclerotic plaque were detected by immunostaining followed by morphometric analysis. Similar to the characteristics of Fas{sup −/−} mice, a model of systemic lupus erythematosus (SLE), ApoE{sup −/−} mice, especially female, displayed significant increases of spleen weight and glomerular area when compared to B6 mice. Also, elevated titers of serum ANA, anti-dsDNA antibody and creatinine and urine protein. Moreover, the expressions of IgG, C3 and macrophage in glomeruli and aortic plaques were found in ApoE{sup −/−} mice. In addition, the IgG and C3 expressions in glomeruli and plaques significantly increased (or a trend of increase) in female ApoE{sup −/−} mice compared with males. Conclusions: Apolipoprotein E-knockout mice on high-fat diet show autoimmune injury on kidney and aorta.

Apolipoprotein E-knockout mice on high-fat diet show autoimmune injury on kidney and aorta

International Nuclear Information System (INIS)

Wang, Yuehai; Lu, Huixia; Huang, Ziyang; Lin, Huili; Lei, Zhenmin; Chen, Xiaoqing; Tang, Mengxiong; Gao, Fei; Dong, Mei; Li, Rongda; Lin, Ling

2014-01-01

Highlights: • Titers of ANA and anti-dsDNA antibodies were similar in ApoE −/− and Fas −/− mice. • The spleen weights and glomerular areas were similar in ApoE −/− and Fas −/− mice. • Expressions of IgG and C3 in glomeruli were similar in ApoE −/− and Fas −/− mice. • IgG, C3 and macrophage infiltration in aortic plaques were found in ApoE −/− mice. - Abstract: Background: Apolipoprotein E-knockout (ApoE −/− ) mice is a classic model of atherosclerosis. We have found that ApoE −/− mice showed splenomegaly, higher titers of serum anti-nuclear antibody (ANA) and anti-dsDNA antibody compared with C57B6/L (B6) mice. However, whether ApoE −/− mice show autoimmune injury remains unclear. Methods and results: Six females and six males in each group, ApoE −/− , Fas −/− and B6 mice, were used in this study. The titers of serum ANA, anti-dsDNA antibody and creatinine and urine protein were measured by ELISA after 4 months of high-fat diet. The spleen weight and the glomerular area were determined. The expressions of IgG, C3 and macrophage in kidney and atherosclerotic plaque were detected by immunostaining followed by morphometric analysis. Similar to the characteristics of Fas −/− mice, a model of systemic lupus erythematosus (SLE), ApoE −/− mice, especially female, displayed significant increases of spleen weight and glomerular area when compared to B6 mice. Also, elevated titers of serum ANA, anti-dsDNA antibody and creatinine and urine protein. Moreover, the expressions of IgG, C3 and macrophage in glomeruli and aortic plaques were found in ApoE −/− mice. In addition, the IgG and C3 expressions in glomeruli and plaques significantly increased (or a trend of increase) in female ApoE −/− mice compared with males. Conclusions: Apolipoprotein E-knockout mice on high-fat diet show autoimmune injury on kidney and aorta

Learning Radiology in an Integrated Problem-Based Learning (PBL ...

African Journals Online (AJOL)

Background: The Faculty of Medicine (FoM) has been training health professions in Uganda since 1924. Five years ago, it decided to change the undergraduate curriculum from traditional to Problem Based Learning (PBL) and adopted the SPICES model. Radiology was integrated into the different courses throughout the 5 ...

Enhanced engraftment of human cells in RAG2/gammac double-knockout mice after treatment with CL2MDP liposomes

NARCIS (Netherlands)

Rozemuller, Henk; Knaän-Shanzer, Shosh; Hagenbeek, Anton; van Bloois, Louis; Storm, Gert; Martens, Anton C. M.

2004-01-01

OBJECTIVE: The ability of human cells to repopulate the bone marrow of nonobese diabetic immunodeficient mice (NOD/SCID) is commonly used as a standard assay to quantify the primitive human hematopoietic stem cell population. We studied the applicability of the immunodeficient RAG2(-/-)gammac(-/-)

Recent developments and assessment of a three-dimensional PBL parameterization for improved wind forecasting over complex terrain

Science.gov (United States)

Kosovic, B.; Jimenez, P. A.; Haupt, S. E.; Martilli, A.; Olson, J.; Bao, J. W.

2017-12-01

At present, the planetary boundary layer (PBL) parameterizations available in most numerical weather prediction (NWP) models are one-dimensional. One-dimensional parameterizations are based on the assumption of horizontal homogeneity. This homogeneity assumption is appropriate for grid cell sizes greater than 10 km. However, for mesoscale simulations of flows in complex terrain with grid cell sizes below 1 km, the assumption of horizontal homogeneity is violated. Applying a one-dimensional PBL parameterization to high-resolution mesoscale simulations in complex terrain could result in significant error. For high-resolution mesoscale simulations of flows in complex terrain, we have therefore developed and implemented a three-dimensional (3D) PBL parameterization in the Weather Research and Forecasting (WRF) model. The implementation of the 3D PBL scheme is based on the developments outlined by Mellor and Yamada (1974, 1982). Our implementation in the Weather Research and Forecasting (WRF) model uses a pure algebraic model (level 2) to diagnose the turbulent fluxes. To evaluate the performance of the 3D PBL model, we use observations from the Wind Forecast Improvement Project 2 (WFIP2). The WFIP2 field study took place in the Columbia River Gorge area from 2015-2017. We focus on selected cases when physical phenomena of significance for wind energy applications such as mountain waves, topographic wakes, and gap flows were observed. Our assessment of the 3D PBL parameterization also considers a large-eddy simulation (LES). We carried out a nested LES with grid cell sizes of 30 m and 10 m covering a large fraction of the WFIP2 study area. Both LES domains were discretized using 6000 x 3000 x 200 grid cells in zonal, meridional, and vertical direction, respectively. The LES results are used to assess the relative magnitude of horizontal gradients of turbulent stresses and fluxes in comparison to vertical gradients. The presentation will highlight the advantages of the 3

Metabolic aspects of growth in HU-treated crown-gall tissue cultures. I. Nicotiana tabacum

Directory of Open Access Journals (Sweden)

Aldona Rennert

2015-01-01

Full Text Available An influence of hydroxyurea (HU on the growth, DNA and RNA contents and protein synthesis in the tobacco tumour tissue culture was studied in comparison with a homologous callus tissue. In conformity with expectations considerable decrease of DNA level in both tissues is a primary effect of HU activity. This results in the growth inhibition and in the secondary metabolic effects; these effects depend not only on the concentration of inhibitor but also on the age of tissue. In spite of some common features the character of these changes shows a distinct differentiation depending on the tissue type. TMs points to specific modifications of the biochemical regulation of growth in a tumour.

Infusion of Trx-1-overexpressing hucMSC prolongs the survival of acutely irradiated NOD/SCID mice by decreasing excessive inflammatory injury.

Science.gov (United States)

Hu, JiangWei; Yang, ZaiLiang; Wang, Jun; Tang, YongYong; Liu, Hao; Zhang, Bin; Chen, Hu

2013-01-01

A protective reagent for ARI should have the ability to repair injured tissue caused by radiation and prevent continuous damage from secondary risk factors. Trx-1 was explored as a candidate therapy for ARI, as it scavenges reactive oxygen species, regulates cell growth and differentiation, participates in immune reactions, and inhibits apoptosis by acting inside and/or outside cells. Trx-1 can also decrease excessive inflammation in ARI by regulating the creation of inflamed media, by inhibiting the activation of complement, and by reducing the chemotaxis, adhesion, and migration of inflammatory cells. As effectively and stably expressing exogenous genes in the long term and regulating immune inflammation and tissue repair, MSC are a good choice for Trx-1 gene therapy. In this study, Trx-1-overexpressing hucMSC-Trx-1 were obtained by adenoviral vector-mediated infection. We first measured the redox capacity of hucMSC-Trx-1 with an antioxidant capacity (T-AOC) assay, a hydrogen peroxide (H2O2) content determination assay in vivo, a H2O2-induced oxidation hemolysis assay, and a lipid peroxidation assay in vitro. Then, we measured survival time, the protection of the hematopoietic system, and the regulation of inflammation in important organs in three treatment groups of NOD/SCID mice (treated with hucMSC-Trx-1, with hucMSC, and with saline) that were exposed to 4.5 Gy (60)Co-γ-ray radiation. The hucMSC-Trx-1 group achieved superior antioxidation results, protecting bone marrow hematopoietic stem cells (Lin(-)CD117(+): hucMSC-Trx-1 vs. hucMSC, PTrx-1 vs. NS, PTrx-1 vs. hucMSC or NS, PTrx-1 vs. NS, PTrx-1 vs. hucMSC, PTrx-1 vs. NS, PTrx-1 vs. hucMSC, PTrx-1 vs. hucMSC or NS, PTrx-1 combines the merits of gene and cell therapy as a multifunctional radioprotector for ARI.

HuB (elavl2 mRNA is restricted to the germ cells by post-transcriptional mechanisms including stabilisation of the message by DAZL.

Directory of Open Access Journals (Sweden)

Sophie E Wiszniak

Full Text Available The ability of germ cells to carry out a gene regulatory program distinct from the surrounding somatic tissue, and their capacity to specify an entire new organism has made them a focus of many studies that seek to understand how specific regulatory mechanisms, particularly post-transcriptional mechanisms, contribute to cell fate. In zebrafish, germ cells are specified through the inheritance of cytoplasmic determinants, termed the germ plasm, which contains a number of maternal mRNAs and proteins. Investigation of several of these messages has revealed that the restricted localisation of these mRNAs to the germ plasm and subsequent germ cells is due to cis-acting sequence elements present in their 3'UTRs. Here we show that a member of the Hu family of RNA-binding proteins, HuB, is maternally provided in the zebrafish embryo and exhibits germ cell specific expression during embryogenesis. Restriction of HuB mRNA to the germ cells is dependent on a number of sequence elements in its 3'UTR, which act to degrade the mRNA in the soma and stabilise it in the germ cells. In addition, we show that the germ cell specific RNA-binding protein DAZL is able to promote HuB mRNA stability and translation in germ cells, and further demonstrate that these activities require a 30 nucleotide element in the 3'UTR. Our study suggests that DAZL specifically binds the HuB 3'UTR and protects the message from degradation and/or enhances HuB translation, leading to the germ cell specific expression of HuB protein.

DNA Barcoding and PBL in an Australian Postsecondary College

Science.gov (United States)

Cross, Joseph; Garard, Helen; Currie, Tina

2018-01-01

DNA barcoding is increasingly being introduced into biological science educational curricula worldwide. The technique has a number of features that make it ideal for science curricula and particularly for Project-Based Learning (PBL). This report outlines the development of a DNA barcoding project in an Australian TAFE college, which also combined…

Zebrafish transgenic line huORFZ is an effective living bioindicator for detecting environmental toxicants.

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Hung-Chieh Lee

Full Text Available Reliable animal models are invaluable for monitoring the extent of pollution in the aquatic environment. In this study, we demonstrated the potential of huORFZ, a novel transgenic zebrafish line that harbors a human upstream open reading frame of the chop gene fused with GFP reporter, as an animal model for monitoring environmental pollutants and stress-related cellular processes. When huORFZ embryos were kept under normal condition, no leaked GFP signal could be detected. When treated with hazardous chemicals, including heavy metals and endocrine-disrupting chemicals near their sublethal concentrations (LC50, huORFZ embryos exhibited different tissue-specific GFP expression patterns. For further analysis, copper (Cu2+, cadmium (Cd2+ and Chlorpyrifos were applied. Cu2+ triggered GFP responses in skin and muscle, whereas Cd2+ treatment triggered GFP responses in skin, olfactory epithelium and pronephric ducts. Moreover, fluorescence intensity, as exhibited by huORFZ embryos, was dose-dependent. After surviving treated embryos were returned to normal condition, survival rates, as well as TUNEL signals, returned to pretreatment levels with no significant morphological defects observed. Such results indicated the reversibility of treatment conditions used in this study, as long as embryos survived such conditions. Notably, GFP signals decreased along with recovery, suggesting that GFP signaling of huORFZ embryos likely reflected the overall physiological condition of the individual. To examine the performance of the huORFZ line under real-world conditions, we placed huORFZ embryos in different river water samples. We found that the huORFZ embryos correctly detected the presence of various kinds of pollutants. Based on these findings, we concluded that such uORFchop-based system can be integrated into a first-line water alarm system monitoring the discharge of hazardous pollutants.

Zebrafish Transgenic Line huORFZ Is an Effective Living Bioindicator for Detecting Environmental Toxicants

Science.gov (United States)

Chu, Chien; Li, Hong-Ping; Tsai, Huai-Jen

2014-01-01

Reliable animal models are invaluable for monitoring the extent of pollution in the aquatic environment. In this study, we demonstrated the potential of huORFZ, a novel transgenic zebrafish line that harbors a human upstream open reading frame of the chop gene fused with GFP reporter, as an animal model for monitoring environmental pollutants and stress-related cellular processes. When huORFZ embryos were kept under normal condition, no leaked GFP signal could be detected. When treated with hazardous chemicals, including heavy metals and endocrine-disrupting chemicals near their sublethal concentrations (LC50), huORFZ embryos exhibited different tissue-specific GFP expression patterns. For further analysis, copper (Cu2+), cadmium (Cd2+) and Chlorpyrifos were applied. Cu2+ triggered GFP responses in skin and muscle, whereas Cd2+ treatment triggered GFP responses in skin, olfactory epithelium and pronephric ducts. Moreover, fluorescence intensity, as exhibited by huORFZ embryos, was dose-dependent. After surviving treated embryos were returned to normal condition, survival rates, as well as TUNEL signals, returned to pretreatment levels with no significant morphological defects observed. Such results indicated the reversibility of treatment conditions used in this study, as long as embryos survived such conditions. Notably, GFP signals decreased along with recovery, suggesting that GFP signaling of huORFZ embryos likely reflected the overall physiological condition of the individual. To examine the performance of the huORFZ line under real-world conditions, we placed huORFZ embryos in different river water samples. We found that the huORFZ embryos correctly detected the presence of various kinds of pollutants. Based on these findings, we concluded that such uORFchop-based system can be integrated into a first-line water alarm system monitoring the discharge of hazardous pollutants. PMID:24594581

Utility of immunodeficient mouse models for characterizing the preclinical pharmacokinetics of immunogenic antibody therapeutics.

Science.gov (United States)

Myzithras, Maria; Bigwarfe, Tammy; Li, Hua; Waltz, Erica; Ahlberg, Jennifer; Giragossian, Craig; Roberts, Simon

Prior to clinical studies, the pharmacokinetics (PK) of antibody-based therapeutics are characterized in preclinical species; however, those species can elicit immunogenic responses that can lead to an inaccurate estimation of PK parameters. Immunodeficient (SCID) transgenic hFcRn and C57BL/6 mice were used to characterize the PK of three antibodies that were previously shown to be immunogenic in mice and cynomolgus monkeys. Four mouse strains, Tg32 hFcRn SCID, Tg32 hFcRn, SCID and C57BL/6, were administered adalimumab (Humira®), mAbX and mAbX-YTE at 1 mg/kg, and in SCID strains there was no incidence of immunogenicity. In non-SCID strains, drug-clearing ADAs appeared after 4-7 days, which affected the ability to accurately calculate PK parameters. Single species allometric scaling of PK data for Humira® in SCID and hFcRn SCID mice resulted in improved human PK predictions compared to C57BL/6 mice. Thus, the SCID mouse model was demonstrated to be a useful tool for assessing the preclinical PK of immunogenic therapeutics.

An Empirical Study on the Influence of PBL Teaching Model on College Students' Critical Thinking Ability

Science.gov (United States)

Zhou, Zhen

2018-01-01

The critical thinking ability is an indispensable ability of contemporary college students, and the PBL teaching model abandons the shortcomings of traditional teaching methods, which is more suitable for the development trend of university curriculum teaching reform in China. In order to understand the influence of PBL teaching mode on college…

Interplay between Individual Creativity and Group Creativity in Problem and Project-Based Learning (PBL) Environment in Engineering Education

DEFF Research Database (Denmark)

Zhou, Chunfang; Kolmos, Anette

2013-01-01

Recent studies regard Problem and Project Based Learning (PBL) as providing a learning environment which fosters both individual and group creativity. This paper focuses on the question: In a PBL environment, how do students perceive the interplay between individual and group creativity? Empirica...

Pharmacological Evaluation of the SCID T Cell Transfer Model of Colitis

DEFF Research Database (Denmark)

Lindebo Holm, Thomas; Poulsen, Steen Seier; Markholst, Helle

2012-01-01

the SCID adoptive transfer colitis model, we have evaluated the effect of currently used IBD drugs and IBD drug candidates, that is, anti-TNF-α, TNFR-Fc, anti-IL-12p40, anti-IL-6, CTLA4-Ig, anti-α4β7 integrin, enrofloxacin/metronidazole, and cyclosporine. We found that anti-TNF-α, antibiotics, anti-IL-12p...

The long and the short of telomeres in bone marrow recipient SCID patients.

Science.gov (United States)

Sarzotti-Kelsoe, Marcella; Daniell, Xiaoju G; Whitesides, John F; Buckley, Rebecca H

2011-04-01

Telomeres are noncoding DNA regions at the end of the chromosomes that are crucial for genome stability. Since telomere length decreases with cell division, they can be used as a signature of cell proliferation history. T-cell reconstitution in severe combined immunodeficiency (SCID) subjects, recipients of T-cell-depleted, allogeneic-related bone marrow cells, is due to the development and maturation of donor T-cell precursors in the infant's vestigial thymus and to homeostatic proliferation of mature T cells in the peripheral organs. Since T-cell function, thymic output, and T-cell clonal diversity are maintained long term in these patients, we investigated whether donor T-cell engraftment resulted in increased telomere shortening. Our study of seven SCID patients, following successful bone marrow transplantation, demonstrates that the patients' peripheral T cells did not exhibit greater than normal telomere shortening.

Chinese business students’ changes in beliefs and strategy use in a constructively aligned PBL course

DEFF Research Database (Denmark)

Zhao, Ke; Zhang, Jie; Du, Xiangyun

2017-01-01

This study adopted a longitudinal retrospective case study approach to investigate Chinese business students’ transitional learning experience in a problem-based learning (PBL) course with innovative assessment practices. The study focused on students’ beliefs and strategy use in a constructively...... that align social constructivist learning principles with students’ beliefs and strategies. The results also highlight the importance of developing appropriate assessment rubrics to enhance student engagement with PBL learning for improved outcomes....

PENINGKATAN KEMAMPUAN PEMECAHAN MASALAH DAN PENGEMBANGAN KARAKTER PADA SISWA KELAS VII MELALUI MODEL PBL BERBANTUAN SCAFFOLDING

Directory of Open Access Journals (Sweden)

Novy Kris Zaini

2016-04-01

Full Text Available Tujuan penelitian ini adalah untuk mengetahui (1 apakah kemampuan pemecahan masalah matematika peserta didik yang diajar dengan model PBL berbantuan scaffolding pada materi pokok segiempat kelas VII dapat mencapai KKM yang ditetapkan, (2 apakah pembelajaran matematika dengan model PBL berbantuan scaffolding pada materi pokok segiempat kelas VII dapat meningkatkan kemampuan pemecahan masalah peserta didik pilihan, (3 apakah pembelajaran matematika dengan model PBL berbantuan scaffolding pada materi pokok segiempat kelas VII dapat meningkatkan karakter rasa ingin tahu peserta didik pilihan. Desain penelitian ini adalah concurrent triangulation (campuran kuatitatif dan kualitatif secara seimbang, menggabungkan antara metode kuantitatif dan metode kualitatif untuk digunakan secara bersama-sama dalam suatu kegiatan penelitian, sehingga diperoleh data yang lebih komprehensif, valid, reliabel dan obyektif. Penentuan sumber data dalam penelitian ini menggunakan teknik triangulasi, yaitu menggabungkan dari berbagai teknik pengumpulan data dan sumber data yang telah ada. Data diperoleh dengan observasi, wawancara, dan dokumentasi yang kemudian dianalisis menggunakan analisis kualitatif, sedangkan tes dan observasi dianalisis menggunakan analisis kuantitatif dan analisis gain untuk mengukur peningkatan. Analisis kualitatif menunjukkan karakter rasa ingin tahu dan kemampuan pemecahan masalah peserta didik meningkat, serta kemampuan pemecahan masalah peserta didik mencapai KKM melalui model pembelajaran PBL

Measurement of hard tissue density of head phantom based on the HU by using CBCT

International Nuclear Information System (INIS)

Kim, Moon Sun; Kang, Dong Wan; Kim, Jae Duk

2009-01-01

The purpose of this study was to determine a conversion coefficient for Hounsfield Units(HU) to material density (g cm -3 ) obtained from cone-beam computed tomography (CBMercuRay TM ) data and to measure the hard tissue density based on the Hounsfield scale on dental head phantom. CT Scanner Phantom (AAPM) equipped with CT Number Insert consists of five cylindrical pins of materials with different densities and teflon ring was scanned by using the CBMercuRay TM (Hitachi, Tokyo, Japan) volume scanner. The raw data were converted into DICOM format and the HU of different areas of CT number insert measured by using CBWorks TM . Linear regression analysis and Student t-test were performed statistically. There was no significant difference (P>0.54) between real densities and measured densities. A linear regression was performed using the density, ρ (g cm -3 ), as the dependent variable in terms of the HU (H). The regression equation obtained was ρ=0.00072 H-0.01588 with an R2 value of 0.9968. Density values based on the Hounsfield scale was 1697.1 ± 24.9 HU in cortical bone, 526.5 ± 44.4 HU in trabecular bone, 2639.1 ± 48.7 HU in enamel, 1246.1 ± 39.4 HU in dentin of dental head phantom. CBCT provides an effective option for determination of material density expressed as Hounsfield Units.

One of the Two Genes Encoding Nucleoid-Associated HU Proteins in Streptomyces coelicolor Is Developmentally Regulated and Specifically Involved in Spore Maturation▿ †

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Salerno, Paola; Larsson, Jessica; Bucca, Giselda; Laing, Emma; Smith, Colin P.; Flärdh, Klas

2009-01-01

Streptomyces genomes encode two homologs of the nucleoid-associated HU proteins. One of them, here designated HupA, is of a conventional type similar to E. coli HUα and HUβ, while the other, HupS, is a two-domain protein. In addition to the N-terminal part that is similar to that of HU proteins, it has a C-terminal domain that is similar to the alanine- and lysine-rich C termini of eukaryotic linker histones. Such two-domain HU proteins are found only among Actinobacteria. In this phylum some organisms have only a single HU protein of the type with a C-terminal histone H1-like domain (e.g., Hlp in Mycobacterium smegmatis), while others have only a single conventional HU. Yet others, including the streptomycetes, produce both types of HU proteins. We show here that the two HU genes in Streptomyces coelicolor are differentially regulated and that hupS is specifically expressed during sporulation, while hupA is expressed in vegetative hyphae. The developmental upregulation of hupS occurred in sporogenic aerial hyphal compartments and was dependent on the developmental regulators whiA, whiG, and whiI. HupS was found to be nucleoid associated in spores, and a hupS deletion mutant had an average nucleoid size in spores larger than that in the parent strain. The mutant spores were also defective in heat resistance and spore pigmentation, although they possessed apparently normal spore walls and displayed no increased sensitivity to detergents. Overall, the results show that HupS is specifically involved in sporulation and may affect nucleoid architecture and protection in spores of S. coelicolor. PMID:19717607

T lymphocytes derived from human cord blood provide effective antitumor immunotherapy against a human tumor

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Kim Tae-Sik

2011-06-01

Full Text Available Abstract Background Although the graft-versus-tumor (GVT effect of donor-derived T cells after allogeneic hematopoietic stem cell transplantation has been used as an effective adoptive immunotherapy, the antitumor effects of cord blood (CB transplantation have not been well studied. Methods We established the animal model by transplantation of CB mononuclear cells and/or tumor cells into NOD/SCID mice. The presence of CB derived T cells in NOD/SCID mice or tumor tissues were determined by flow cytometric and immunohistochemical analysis. The anti-tumor effects of CB derived T cells against tumor was determined by tumor size and weight, and by the cytotoxicity assay and ELISPOT assay of T cells. Results We found dramatic tumor remission following transfer of CB mononuclear cells into NOD/SCID mice with human cervical tumors with a high infiltration of CD3+ T cells in tumors. NOD/SCID mice that receive neonatal CB transplants have reconstituted T cells with significant antitumor effects against human cervical and lung tumors, with a high infiltration of CD3+ T cells showing dramatic induction of apoptotic cell death. We also confirmed that T cells showed tumor specific antigen cytotoxicity in vitro. In adoptive transfer of CD3+ T cells into mice with pre-established tumors, we observed much higher antitumor effects of HPV-specific T cells by ELISPOT assays. Conclusions Our results show that CB derived T lymphocytes will be useful for novel immunotherapeutic candidate cells for therapy of several tumors in clinic.

Obese Neuronal PPARγ Knockout Mice Are Leptin Sensitive but Show Impaired Glucose Tolerance and Fertility.

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Fernandez, Marina O; Sharma, Shweta; Kim, Sun; Rickert, Emily; Hsueh, Katherine; Hwang, Vicky; Olefsky, Jerrold M; Webster, Nicholas J G

2017-01-01

The peroxisome-proliferator activated receptor γ (PPARγ) is expressed in the hypothalamus in areas involved in energy homeostasis and glucose metabolism. In this study, we created a deletion of PPARγ brain-knockout (BKO) in mature neurons in female mice to investigate its involvement in metabolism and reproduction. We observed that there was no difference in age at puberty onset between female BKOs and littermate controls, but the BKOs gave smaller litters when mated and fewer oocytes when ovulated. The female BKO mice had regular cycles but showed an increase in the number of cycles with prolonged estrus. The mice also had increased luteinizing hormone (LH) levels during the LH surge and histological examination showed hemorrhagic corpora lutea. The mice were challenged with a 60% high-fat diet (HFD). Metabolically, the female BKO mice showed normal body weight, glucose and insulin tolerance, and leptin levels but were protected from obesity-induced leptin resistance. The neuronal knockout also prevented the reduction in estrous cycles due to the HFD. Examination of ovarian histology showed a decrease in the number of primary and secondary follicles in both genotypes due to the HFD, but the BKO ovaries showed an increase in the number of hemorrhagic follicles. In summary, our results show that neuronal PPARγ is required for optimal female fertility but is also involved in the adverse effects of diet-induced obesity by creating leptin resistance potentially through induction of the repressor Socs3. Copyright © 2017 by the Endocrine Society.

Hidden realities inside PBL design processes

DEFF Research Database (Denmark)

Pihl, Ole Verner

2015-01-01

Design Process, but is a group-based architecture and design education better than that which is individually based? How does PBL affect space, form, and creative processes? Hans Kiib, professor and one of the founders of the Department of Architecture and Design in Aalborg, describes his intentions...... are passing from a complex world into one based on super complexity? Could Gaston Bachelard (1958), who writes in his book The Poetic of Space "that poets and artists are born phenomenologists," help architecture and design students in their journey to find his/her own professional expression? This paper...

Socially dominant mice in C57BL6 background show increased social motivation.

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Kunkel, Thaddeus; Wang, Hongbing

2018-01-15

A series of behavioral tests measuring social dominance, social motivation, and non-social motivation are examined in adult male C57BL6 mice. By using the well-known tube dominance test to determine social dominance and rank, we find that, in the absence of competition for resource and mating, group-housed mouse cage-mates display stable and mostly linear and transitive social hierarchies. Mice with top and bottom social ranks are subjected to a three-chamber social interaction test to measure social motivation. The top ranked mice spend more time interacting with a stranger mouse than the bottom ranked mice, suggesting that social dominance may positively influence social motivation. When subjected to a novel environment, mice with different social ranks show similar locomotion and exploring activity in the open field test, suggesting no detectable difference in certain aspects of non-social motivation. These results demonstrate a behavioral correlation between social dominance and social motivation. Copyright © 2017 Elsevier B.V. All rights reserved.

Transgenic Mice Overexpressing Vitamin D Receptor (VDR) Show Anti-Inflammatory Effects in Lung Tissues.

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Ishii, Masaki; Yamaguchi, Yasuhiro; Isumi, Kyoko; Ogawa, Sumito; Akishita, Masahiro

2017-12-01

Vitamin D insufficiency is increasingly recognized as a prevalent problem worldwide, especially in patients with a chronic lung disease. Chronic obstructive pulmonary disease (COPD) is a type of chronic inflammatory lung disease. Previous clinical studies have shown that COPD leads to low vitamin D levels, which further increase the severity of COPD. Vitamin D homeostasis represents one of the most important factors that potentially determine the severity of COPD. Nonetheless, the mechanisms underlying the anti-inflammatory effects of vitamin D receptor (VDR) in lung tissues are still unclear. To investigate the anti-inflammatory effects of VDR, we generated transgenic mice that show lung-specific VDR overexpression under the control of the surfactant protein C promoter (TG mice). The TG mice were used to study the expression patterns of proinflammatory cytokines using real-time polymerase chain reaction and immunohistochemistry. The TG mice had lower levels of T helper 1 (Th1)-related cytokines than wild-type (WT) mice did. No significant differences in the expression of Th2 cytokines were observed between TG and WT mice. This study is the first to achieve lung-specific overexpression of VDR in TG mice: an interesting animal model useful for studying the relation between airway cell inflammation and vitamin D signaling. VDR expression is an important factor that influences anti-inflammatory responses in lung tissues. Our results show the crucial role of VDR in anti-inflammatory effects in lungs; these data are potentially useful for the treatment or prevention of COPD.

Implementation of problem-based learning (PBL) approach to improve student’s academic achievement and creativity on the topic of electrolyte and non-electrolyte solutions at vocational school

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Wahyu, W.; Kurnia; Syaadah, R. S.

2018-05-01

The purpose of study was to investigate the implementation of PBL to improve student’s academic achievement and creativity on the topic of electrolyte and non-electrolye solutions. This study was conducted as a descriptive method with case study design. Subject of this study consisted of 30 students in the class X. Instruments used in the study included tests and observation sheets. Student’s achievement changes is calculated using N-gain formula, hereafter, the data that have been processed then was analyzed descriptively. The results showed that generally academic achievement and creativity of students has increased as indicated by the value of N-gain (0.667; 0.656). The results of the study also showed that there was a correlation with the moderate category between the academic achievement and the student’s creative thinking as indicated by (r = 0.413), meanwhile, the relationship between academic achievement and creativity(r = 0.340) that belongs to the weak category. Implementation of PBL had a good response from students with percentage 80.3%. Based on these findings, PBL is recommended to be applied on the learning process for other chemistry topics that suitable in term of characteristics between learning materials and PBL stages in order to develop academic achievement and creativity of students.

T-cell-dependent control of acute Giardia lamblia infections in mice.

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Singer, S M; Nash, T E

2000-01-01

We have studied immune mechanisms responsible for control of acute Giardia lamblia and Giardia muris infections in adult mice. Association of chronic G. lamblia infection with hypogammaglobulinemia and experimental infections of mice with G. muris have led to the hypothesis that antibodies are required to control these infections. We directly tested this hypothesis by infecting B-cell-deficient mice with either G. lamblia or G. muris. Both wild-type mice and B-cell-deficient mice eliminated the vast majority of parasites between 1 and 2 weeks postinfection with G. lamblia. G. muris was also eliminated in both wild-type and B-cell-deficient mice. In contrast, T-cell-deficient and scid mice failed to control G. lamblia infections, as has been shown previously for G. muris. Treatment of wild-type or B-cell-deficient mice with antibodies to CD4 also prevented elimination of G. lamblia, confirming a role for T cells in controlling infections. By infecting mice deficient in either alphabeta- or gammadelta-T-cell receptor (TCR)-expressing T cells, we show that the alphabeta-TCR-expressing T cells are required to control parasites but that the gammadelta-TCR-expressing T cells are not. Finally, infections in mice deficient in production of gamma interferon or interleukin 4 (IL-4) and mice deficient in responding to IL-4 and IL-13 revealed that neither the Th1 nor the Th2 subset is absolutely required for protection from G. lamblia. We conclude that a T-cell-dependent mechanism is essential for controlling acute Giardia infections and that this mechanism is independent of antibody and B cells.

Short-interval test-retest interrater reliability of the Dutch version of the structured clinical interview for DSM-IV personality disorders (SCID-II)

NARCIS (Netherlands)

Weertman, A; ArntZ, A; Dreessen, L; van Velzen, C; Vertommen, S

2003-01-01

This study examined the short-interval test-retest reliability of the Structured Clinical Interview (SCID-II: First, Spitzer, Gibbon, & Williams, 1995) for DSM-IV personality disorders (PDs). The SCID-II was administered to 69 in- and outpatients on two occasions separated by 1 to 6 weeks. The

The Structured Clinical Interview for DSM-IV Childhood Diagnoses (Kid-SCID): first psychometric evaluation in a Dutch sample of clinically referred youths

NARCIS (Netherlands)

Roelofs, J.; Muris, P.; Braet, C.; Arntz, A.; Beelen, I.

2015-01-01

The Structured Clinical Interview for DSM-IV Childhood Disorders (Kid-SCID) is a semi-structured interview for the classification of psychiatric disorders in children and adolescents. This study presents a first evaluation of the psychometric properties of the Kid-SCID in a Dutch sample of children

From Print to Digital Platforms: A PBL Framework for Fostering Multimedia Competencies and Consciousness in Traditional Journalism Education

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Goh, Debbie; Kale, Ugur

2015-01-01

The project-based learning (PBL) approach closely reflects the tenets of journalism and provides a potential pedagogical guide for transforming traditional journalism education. This study operationalizes and applies a PBL framework in digitizing a print journalism course. The findings illustrate how the presence of seven key elements of PBL…

HuR and podoplanin expression is associated with a high risk of malignant transformation in patients with oral preneoplastic lesions.

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Habiba, Umma; Kitamura, Tetsuya; Yanagawa-Matsuda, Aya; Higashino, Fumihiro; Hida, Kyoko; Totsuka, Yasunori; Shindoh, Masanobu

2016-11-01

The risk of malignant transformation in oral preneoplastic lesions (OPLs) is challenging to assess. The objective of the present study was to determine the expression of ELAV like RNA binding protein 1 (HuR) and podoplanin in OPLs, and to evaluate the use of each protein as biomarkers for the risk assessment of malignant transformations. Immunohistochemistry for HuR and podoplanin was performed on the tissues of 51 patients with OPL, including cases of low grade dysplasia (LGD) and high grade dysplasia (HGD). The association between the protein expression patterns and clinicopathological parameters, including oral cancer free survival (OCFS) time, was analyzed during the follow-up period. HuR and podoplanin expression was observed in 28 (55%) and 36 (71%) of 51 patients, respectively. Kaplan-Meier analysis showed that the expression of HuR and podoplanin was associated with the risk of progression to oral cancer (P<0.05). Multivariate analysis revealed that HuR and podoplanin expression was associated with a 2.93-fold (95% confidence interval (CI), 0.98-10.34; P=0.055) and 2.06-fold (95% CI, 0.55-8.01; P=0.283) increase in risk of malignant transformation, respectively. The risk of OPL malignant transformation was considerably increased with the coexpression of HuR and podoplanin compared with the histological grading (95% CI, 1.64-23.59; P=0.005). The results of the present study demonstrated that the expression of HuR and podoplanin associates with malignant transformation and suggests that the proteins may be used as biomarkers to identify OPL patients with an increased risk of cancer development.

MSA Mimic? Rare Occurrence of Anti-Hu Autonomic Failure and Thymoma in a Patient with Parkinsonism: Case Report and Literature Review

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Vito A. G. Ricigliano

2018-01-01

Full Text Available Thymoma is a tumor originating from thymic gland, frequently manifesting with paraneoplastic neurological disorders. Its association with paraneoplastic dysautonomia is relatively uncommon. Here, we describe the challenging case of a 71 year-old female who developed subacute autonomic failure with digestive pseudo-obstruction, dysphagia, urinary tract dysfunction and orthostatic hypotension complicating an underlying extrapyramidal syndrome that had started 3 months before hospital admission. Autonomic symptoms had 2-month course and acutely worsened just before and during hospitalization. Combination of severe dysautonomia and parkinsonism mimicked rapidly progressing multiple system atrophy. However, diagnostic exams showed thymic tumor with positive anti-Hu antibodies on both serum and cerebrospinal fluid. Complete response of dysautonomia to immunoglobulins followed by thymectomy confirmed the diagnosis of anti-Hu-related paraneoplastic neurological syndrome. With regards to extrapyramidal symptoms, despite previous descriptions of paraneoplastic parkinsonism caused by other antineuronal antibodies, in our case no relation between anti-Hu and parkinsonism could be identified. A literature review of published reports describing anti-Hu positivity in thymic neoplasms highlighted that a definite autonomic disease due to anti-Hu antibodies is extremely rare in patients with thymoma but without myasthenia gravis, with only one case published so far.

Double negative (CD3+ 4- 8- TCR alphabeta splenic cells from young NOD mice provide long-lasting protection against type 1 diabetes.

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Beverly Duncan

2010-07-01

Full Text Available Double negative CD3(+4(-8(- TCR alphabeta splenic cells (DNCD3 can suppress the immune responses to allo and xenografts, infectious agents, tumors, and some autoimmune disorders. However, little is known about their role in autoimmune diabetes, a disease characterized by the reduction of insulin production subsequent to destruction of pancreatic beta-cells by a polyclonal population of self-reactive T-cells. Herein, we analyzed the function and phenotype of DNCD3 splenic cells in young NOD mice predisposed to several autoimmune disorders among which, the human-like autoimmune diabetes.DNCD3 splenic cells from young NOD mice (1 provided long-lasting protection against diabetes transfer in NOD/Scid immunodeficient mice, (2 proliferated and differentiated in the spleen and pancreas of NOD/Scid mice and pre-diabetic NOD mice into IL-10-secreting T(R-1 like cells in a Th2-like environment, and (3 their anti-diabetogenic phenotype is CD3(+(CD4(-CD8(-CD28(+CD69(+CD25(low Foxp3(- iCTLA-4(-TCR alphabeta(+ with a predominant Vbeta13 gene usage.These findings delineate a new T regulatory component in autoimmune diabetes apart from that of NKT and CD4(+CD25(high Foxp3(+T-regulatory cells. DNCD3 splenic cells could be potentially manipulated towards the development of autologous cell therapies in autoimmune diabetes.

Feasibility of PBL implementation in clinical courses of nursing and midwifery from the viewpoints of faculty members of Tabriz University of Medical Sciences

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Vahidi R.Gh

2004-01-01

Full Text Available Background: PBL, as a teaching method, has a basic role in promoting education level and combining the theoretical and practical knowledge. But there still exist serious obstacles to implementing this educational method Purpose: To recognize the impediments an obstacle preventing PBL method implementation. Methods: The Subjects studied in this research are all the tutors who taught basic and clinical courses in the faculty of nursing and midwifery in the first and second terms of the year 2001-2002. Choosing subjects was done by using census method and the number of subjects was 33 basic course teachers and 20 clinical course teachers. A questionnaire developed based on the studies’ goals was the tool used for collecting data. Data was analysed by means of SPSS/Win 10 Soft ware using descriptive statistics Results: The 95% of basic course teachers and 93.9% clinical course teachers think of the conditions and facilities needed for implementing PBL as of medium level. Tutors believe that most of the impediments are related to student's lack of group work skills, and the skills needed for making correct communication, and the need for students practical participation in PBL for making them ready and receptive. They also relate most of the strong points to PBL's being efficient in training community – oriented students. The tutors state that performing PBL does not decrease their motivation at all, due to the change in their role from lecturer to facilitator. Conclusion: The Although findings of this research indicate that the conditions needed for implementing PBL exist at present, still there are many obstacles to its performance such as student's lack of group work skills and their disability in making correct interaction, costliness of beginning and marinating PBL, large number of students and lack of tutors Keywords: PBL IMPLEMENTATION, MEDICAL EDUCATION

Mitogen-activated protein kinase phosphatase-1 expression in macrophages is controlled by lymphocytes during macrophage activation.

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Luo, Chong; Yang, Xiqiang; Yao, Lan; Jiang, Liping; Liu, Wei; Li, Xin; Wang, Lijia

2012-01-01

The viewpoints on the control of innate immune cells by the adaptive immune system during sepsis remain controversial. Mitogen-activated protein kinase phosphatase-1 (MKP-1) is essential to the negative control of innate immunity and suppresses the activation of macrophages by inhibiting activated mitogen-activated protein kinase (MAPK). The purpose of the current study was to observe inflammatory response and macrophage activation in mice with severe combined immunodeficiency (SCID) with endotoxemia and to determine the role of MKP-1 in the control of macrophage activation by the adaptive immune system. Endotoxemia was induced in wild-type and SCID mice by an intraperitoneal injection of lipopolysaccharide (LPS), and all of the SCID mice died. SCID mice produced more inflammatory cytokines than BALB/c mice systemically and locally. TNF-α mRNA expression was higher and MKP-1 mRNA expression was lower in peritoneal macrophages (PMa) from SCID mice compared to PMa from wild-type mice after and even before LPS injection. Thioglycollate-stimulated PMa from wild-type mice were stimulated with LPS in vitro in the presence or absence of pan-T cells. The levels of TNF-α and IL-6 were higher in the supernatants from PMa cultured alone compared to PMa co-cultured with pan-T cells, and PMa MKP-1 mRNA and protein expression were higher when PMa were co-cultured with pan-T cells. Therefore, pan-T cells can up-regulate MKP-1 expression in macrophages and inhibit the secretion of inflammatory cytokines secretion by macrophages. In SCID mice, lymphocyte deficiency, especially T cell deficiency, causes insufficient MKP-1 expression in macrophages, which can be responsible for the severe inflammation and bad prognosis of septic SCID mice. MKP-1 plays an important role in the control of macrophage activation by the adaptive immune system.

Qualitative Research in PBL in Health Sciences Education: A Review

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Jin, Jun; Bridges, Susan

2016-01-01

Context: Qualitative methodologies are relatively new in health sciences education research, especially in the area of problem-based learning (PBL). A key advantage of qualitative approaches is the ability to gain in-depth, textured insights into educational phenomena. Key methodological issues arise, however, in terms of the strategies of…

Immunogenicity, protective efficacy, and non-replicative status of the HSV-2 vaccine candidate HSV529 in mice and guinea pigs.

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Bernard, Marie-Clotilde; Barban, Véronique; Pradezynski, Fabrine; de Montfort, Aymeric; Ryall, Robert; Caillet, Catherine; Londono-Hayes, Patricia

2015-01-01

HSV-2 vaccine is needed to prevent genital disease, latent infection, and virus transmission. A replication-deficient mutant virus (dl5-29) has demonstrated promising efficacy in animal models of genital herpes. However, the immunogenicity, protective efficacy, and non-replicative status of the highly purified clinical vaccine candidate (HSV529) derived from dl5-29 have not been evaluated. Humoral and cellular immune responses were measured in mice and guinea pigs immunized with HSV529. Protection against acute and recurrent genital herpes, mortality, latent infection, and viral shedding after vaginal HSV-2 infection was determined in mice or in naïve and HSV-1 seropositive guinea pigs. HSV529 replication and pathogenicity were investigated in three sensitive models of virus replication: severe combined immunodeficient (SCID/Beige) mice inoculated by the intramuscular route, suckling mice inoculated by the intracranial route, and vaginally-inoculated guinea pigs. HSV529 immunization induced HSV-2-neutralizing antibody production in mice and guinea pigs. In mice, it induced production of specific HSV-2 antibodies and splenocytes secreting IFNγ or IL-5. Immunization effectively prevented HSV-2 infection in all three animal models by reducing mortality, acute genital disease severity and frequency, and viral shedding. It also reduced ganglionic viral latency and recurrent disease in naïve and HSV-1 seropositive guinea pigs. HSV529 replication/propagation was not detected in the muscles of SCID/Beige mice, in the brains of suckling mice, or in vaginal secretions of inoculated guinea pigs. These results confirm the non-replicative status, as well as its immunogenicity and efficacy in mice and guinea pigs, including HSV-1 seropositive guinea pigs. In mice, HSV529 produced Th1/Th2 characteristic immune response thought to be necessary for an effective vaccine. These results further support the clinical investigation of HSV529 in human subjects as a prophylactic vaccine.

Immunogenicity, protective efficacy, and non-replicative status of the HSV-2 vaccine candidate HSV529 in mice and guinea pigs.

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Marie-Clotilde Bernard

Full Text Available HSV-2 vaccine is needed to prevent genital disease, latent infection, and virus transmission. A replication-deficient mutant virus (dl5-29 has demonstrated promising efficacy in animal models of genital herpes. However, the immunogenicity, protective efficacy, and non-replicative status of the highly purified clinical vaccine candidate (HSV529 derived from dl5-29 have not been evaluated. Humoral and cellular immune responses were measured in mice and guinea pigs immunized with HSV529. Protection against acute and recurrent genital herpes, mortality, latent infection, and viral shedding after vaginal HSV-2 infection was determined in mice or in naïve and HSV-1 seropositive guinea pigs. HSV529 replication and pathogenicity were investigated in three sensitive models of virus replication: severe combined immunodeficient (SCID/Beige mice inoculated by the intramuscular route, suckling mice inoculated by the intracranial route, and vaginally-inoculated guinea pigs. HSV529 immunization induced HSV-2-neutralizing antibody production in mice and guinea pigs. In mice, it induced production of specific HSV-2 antibodies and splenocytes secreting IFNγ or IL-5. Immunization effectively prevented HSV-2 infection in all three animal models by reducing mortality, acute genital disease severity and frequency, and viral shedding. It also reduced ganglionic viral latency and recurrent disease in naïve and HSV-1 seropositive guinea pigs. HSV529 replication/propagation was not detected in the muscles of SCID/Beige mice, in the brains of suckling mice, or in vaginal secretions of inoculated guinea pigs. These results confirm the non-replicative status, as well as its immunogenicity and efficacy in mice and guinea pigs, including HSV-1 seropositive guinea pigs. In mice, HSV529 produced Th1/Th2 characteristic immune response thought to be necessary for an effective vaccine. These results further support the clinical investigation of HSV529 in human subjects as a

MRI-tracking of transplanted human ASC in a SCID mouse model

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Siegmund, Birte J.; Kasten, Annika [Department of Oral and Maxillofacial Surgery, Facial Plastic Surgery, Rostock University Medical Center (Germany); Kühn, Jens-Peter [Institute of Diagnostic Radiology and Neuroradiology, Greifswald University Medical Center (Germany); Winter, Karsten [Institute of Anatomy, Faculty of Medicine, University of Leipzig (Germany); Grüttner, Cordula [Micromod Partikeltechnologie GmbH, Rostock (Germany); Frerich, Bernhard, E-mail: bernhard.frerich@med.uni-rostock.de [Department of Oral and Maxillofacial Surgery, Facial Plastic Surgery, Rostock University Medical Center (Germany)

2017-04-01

Background: Regarding strategies improving the efficacy of stem cell transplantation in adipose tissue engineering, cell tracking might be useful. Here we report the in vivo tracking of adipose tissue derived stem cells (ASC) by means of nanoparticle labeling and magnetic resonance imaging (MRI). Here we report the in vivo tracking of adipose tissue derived stromal cells (ASC) by means of nanoparticle labeling and magnetic resonance imaging (MRI). Materials and methods: Human ASC were amplified and labeled with two types of magnetic nanoparticles (MNP), BNF starch and nanomag®-D-spio. Adipose tissue constructs were fabricated by seeding collagen scaffolds with labeled and unlabeled ASCs. Constructs were implanted subcutaneously in the back of severe combined immunodeficient (SCID) mice (n =69, group 1: control with cells w/o label, group 2: BNF starch labeled cells, group 3: nanomag®-D-spio labeled cells). MRI scans were performed at 24 hours, four, twelve and 28 days and four months in a 7.1 T animal device. Explanted constructs were analyzed histomorphometrically. Results: MRI scans showed high contrast of the labeled cells in t2-tse-sequence compared to unlabeled controls. Loss of volume of the implants was observed over time due to partial loss for transplanted cells without significant difference (level of significance p<0.017). Compared to histomorphometry, there was found a positiv correlations in measurement of implant size with a significant at day four (correlation coefficient =0.643; p=0.024) and day twelve (correlation coefficient =0.687; p=0.010). Additional Prussian blue stain showed iron in all implants. Significant differences between the three groups (significance level p<0.017) were found after twelve days between control group and group 3 (p=0.008) and after 28 days between control group and group 2 and 3 (p=0.011). Conclusion: Both MNPs might be suitable for tracking of ASC in vivo and show long term stability over 4 months. - Highlights: �

Runaway Train: A Leaky Radiosensitive SCID with Skin Lesions and Multiple Lymphomas

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Børre Fevang

2018-01-01

Full Text Available The nuclease Artemis is essential for the development of T-cell and B-cell receptors and repair of DNA double-strand breaks, and a loss of expression or function will lead to a radiosensitive severe combined immunodeficiency with no functional T-cells or B-cells (T-B-SCID. Hypomorphic mutations in the Artemis gene can lead to a functional, but reduced, T-cell and B-cell repertoire with a more indolent clinical course called “leaky” SCID. Here, we present the case of a young man who had increasingly aggressive lymphoproliferative skin lesions from 2 years of age which developed into multiple EBV+ B-cell lymphomas, where a hypomorphic mutation in the Artemis gene was found in a diagnostic race against time using whole exome sequencing. The patient was given a haploidentical stem cell transplant while in remission for his lymphomas and although the initial course was successful, he succumbed to a serious Pneumocystis jirovecii pneumonia 5 months after the transplant. The case underscores the importance of next-generation sequencing in the diagnosis of patients with suspected severe immunodeficiency.

Successful Project Based Learning (PBL) Across Disciplines Geared Towards Middle School: An Example from a Wetlands PBL Unit in Reno, Nevada, USA

Science.gov (United States)

Howard, K. L.; Suchy-Mabrouk, A.; Noble, P. J.; Mensing, S. A.; Ewing-Taylor, J.

2014-12-01

A growing need for broad dissemination of current scientific research and improved scientific literacy requires new models of professional development that allow for direct collaboration between educators and university researchers. One example is a project funded by the National Science Foundation (NSF) as part of a study titled, "Reconstructing 2500 years of environmental change at the periphery of Rome: Integrating paleoecology and socioeconomic history to understand human response to climate." This project involves a team of middle school teachers working with researchers at the University of Nevada, Reno (UNR) to gain first-hand knowledge in multidisciplinary research connecting science and society, and applies a similar approach in the classroom. In 2013, the team's science teacher traveled to Italy as a member of the science research group. A series of workshops introduced the remaining teachers to the research project. Teachers collaborated to develop a Project Based Learning (PBL) unit that incorporated Next Generation Science Standards and encompassed English, Social Studies, Math, and Science curricula using a pedagogical approach different from the single subject-based PBL's usually taught in their school district. The PBL unit draws on the NSF study and focuses on exploring the balance between economic and environmental issues surrounding local wetlands. In May 2014, 160 middle school students worked in groups to create and test a question about physio-chemical parameters in a nearby wetland and used these data to discuss local economic development. Initially, students claimed polarized views of environmental issues or economic development interests; however, during a multimedia session showcasing results, students communicated more informed perspectives that clearly incorporated knowledge gained from their own research. Some students were able to make recommendations for good practices involving planned economic development near the wetland

Brain mitochondria from DJ-1 knockout mice show increased respiration-dependent hydrogen peroxide consumption

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Pamela Lopert

2014-01-01

Full Text Available Mutations in the DJ-1 gene have been shown to cause a rare autosomal-recessive genetic form of Parkinson’s disease (PD. The function of DJ-1 and its role in PD development has been linked to multiple pathways, however its exact role in the development of PD has remained elusive. It is thought that DJ-1 may play a role in regulating reactive oxygen species (ROS formation and overall oxidative stress in cells through directly scavenging ROS itself, or through the regulation of ROS scavenging systems such as glutathione (GSH or thioredoxin (Trx or ROS producing complexes such as complex I of the electron transport chain. Previous work in this laboratory has demonstrated that isolated brain mitochondria consume H2O2 predominantly by the Trx/Thioredoxin Reductase (TrxR/Peroxiredoxin (Prx system in a respiration dependent manner (Drechsel et al., Journal of Biological Chemistry, 2010. Therefore we wanted to determine if mitochondrial H2O2 consumption was altered in brains from DJ-1 deficient mice (DJ-1−/−. Surprisingly, DJ-1−/− mice showed an increase in mitochondrial respiration-dependent H2O2 consumption compared to controls. To determine the basis of the increased H2O2 consumption in DJ1−/− mice, the activities of Trx, Thioredoxin Reductase (TrxR, GSH, glutathione disulfide (GSSG and glutathione reductase (GR were measured. Compared to control mice, brains from DJ-1−/− mice showed an increase in (1 mitochondrial Trx activity, (2 GSH and GSSG levels and (3 mitochondrial glutaredoxin (GRX activity. Brains from DJ-1−/− mice showed a decrease in mitochondrial GR activity compared to controls. The increase in the enzymatic activities of mitochondrial Trx and total GSH levels may account for the increased H2O2 consumption observed in the brain mitochondria in DJ-1−/− mice perhaps as an adaptive response to chronic DJ-1 deficiency.

Treatment of depression with Chai Hu Shu Gan San: a systematic review and meta-analysis of 42 randomized controlled trials.

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Sun, Yan; Xu, Xia; Zhang, Jinping; Chen, Yuanyuan

2018-02-17

Depression is a common mental disorder. Chai Hu Shu Gan San, a traditional Chinese medicine, is used to treat depression empirically. We present a systematic review and meta-analysis of the therapeutic efficacy and safety of Chai Hu Shu Gan San in treating depression. Several databases, including PubMed, China National Knowledge Internet, Wanfang, Chongqing VIP, and the Cochrane library, were systematically searched from their date of foundation to January 1, 2017. In this review, wehave included randomized control trials that compared Chai Hu Shu Gan San (or its combination with a regular Western medicine) with a regular Western medicine alone for the treatment of depression. Two investigators independently extracted and analyzed the data using RevMan 5.2.0 software. Mean difference (with a 95% confidence interval) was used as efficacy indices for outcomes. We included 42 studies involving 3234 patients with depression in 15 different types of diseases. Meta analyses showed better effect of Chai Hu Shu Gan San than fluoxetine for pure depression (MD = - 1.59, from - 2.82 to - 0.37, 4 trials, I 2  = 26%), for post-stroke depression (MD = - 4.20, from - 6.20 to - 2.19, 7 trials, I 2  = 96%), and for postpartum depression (MD = - 4.10, from - 7.48 to - 0.72 7 trials, I 2  = 86%). None of the articles reported severe adverse events of oral administration of Chai Hu Shu Gan San. Furthermore, any adverse effects of using Chai Hu Shu Gan San alone were fewer than those of regular Western medicines. This review found that Chai Hu Shu Gan San has some advantages in treating depression, especially post-stroke depression and post-partum depression. A meticulously designed and conducted randomized control trial is needed for further evaluation.

HuR/ELAVL1 RNA binding protein modulates interleukin-8 induction by muco-active ribotoxin deoxynivalenol

International Nuclear Information System (INIS)

Choi, Hye Jin; Yang, Hyun; Park, Seong Hwan; Moon, Yuseok

2009-01-01

HuR/Elav-like RNA binding protein 1 (ELAVL1) positively regulates mRNA stability of AU-rich elements (ARE)-containing transcript such as pro-inflammatory cytokines. Ribotoxic stresses can trigger the production of pro-inflammatory mediators by enhancing mRNA stability and the transcriptional activity. We investigated the effects of ribotoxin deoxynivalenol (DON) on HuR translocation and its involvement in the regulation of the pro-inflammatory interleukin-8 (IL-8) mRNA stability. Exposure to the muco-active DON induced nuclear export of both endogenous and exogenous HuR RNA binding protein in human intestinal epithelial cells. Moreover, the interference with HuR protein production suppressed ribotoxic DON-induced IL-8 secretion and its mRNA stability. Cytoplasmic HuR protein interacted with IL-8 mRNA and the complex stabilization was due to the presence of 3'-untranslated region of the transcript. Partly in terms of IL-8-modulating transcription factors, HuR protein was demonstrated to be positively and negatively associated with DON-induced early growth response gene 1 (EGR-1) and activating transcription factor 3 (ATF3), respectively. HuR was a critical mechanistic link between ribotoxic stress and the pro-inflammatory cytokine production, and may have a broader functional significance with regard to mucosal insults since ribotoxic stress responses are also produced upon interactions with the diverse environment of gut.

The monomeric form of Neisseria DNA mimic protein DMP19 prevents DNA from binding to the histone-like HU protein

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Ko, Tzu-Ping; Liao, Yi-Ting; Hsu, Kai-Cheng

2017-01-01

DNA mimicry is a direct and effective strategy by which the mimic competes with DNA for the DNA binding sites on other proteins. Until now, only about a dozen proteins have been shown to function via this strategy, including the DNA mimic protein DMP19 from Neisseria meningitides. We have shown previously that DMP19 dimer prevents the operator DNA from binding to the transcription factor NHTF. Here, we provide new evidence that DMP19 monomer can also interact with the Neisseria nucleoid-associated protein HU. Using BS3 crosslinking, gel filtration and isothermal titration calorimetry assays, we found that DMP19 uses its monomeric form to interact with the Neisseria HU dimer. Crosslinking conjugated mass spectrometry was used to investigate the binding mode of DMP19 monomer and HU dimer. Finally, an electrophoretic mobility shift assay (EMSA) confirmed that the DNA binding affinity of HU is affected by DMP19. These results showed that DMP19 is bifunctional in the gene regulation of Neisseria through its variable oligomeric forms. PMID:29220372

The Impact of the Implementation of the PBL for EFL Interdisciplinary Study in a Local Thai Context

DEFF Research Database (Denmark)

Coffin, Prarthana

2013-01-01

Can Problem-Based Learning (PBL) principles and practices be applied to language education, especially within an academic writing course? The answer to this question remains ambivalent to many language teachers and educators. This study describes how PBL principles are used as the fundamental basis...... the benefits gained in their learning experience from the PBL process. The focused benefits gained in this case are motivation in learning, communication skills, collaborative skills, critical thinking, problem-solving and self-directed learning skills. Furthermore, triangulation between teachers’ perception...... of restructuring English as a foreign language (EFL) writing course, called Writing3, at a Thai university. The study also examines students’ and teachers’ perceptions as related to their learning experiences. The case study involves 182 English major students and 3 English teachers who participated in learning...

[Application of PBL combined with SP method in during-course practice of endodontics for undergraduate dental students].

Science.gov (United States)

Shao, Li-Na; Qiu, Li-Hong; Zhan, Fu-Liang; Xue, Ming

2016-10-01

To apply problem-based learning (PBL) combined with standardized patients(SP) in during-course practice of endodontics for undergraduate dental students, in order to improve the teaching quality. One hundred and four undergraduate dental students of China Medical University School of Stomatology were randomly divided into 2 groups, 52 students in each group. One group were taught with PBL combined with SP while the other group with lecture-based learning (LBL) alone. The teaching effect was measured with examination and questionnaire survey. The data were analyzed by Student's t test using SPSS 11.5 software package. Students in PBL combined with SP group was better than LBL group in case analysis, didactic tests, practical tests and total scores, and there was significant difference between the two groups (Pendodontics to undergraduate dental students.

Nav 1.8-null mice show stimulus-dependent deficits in spinal neuronal activity

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Wood John N

2006-02-01

Full Text Available Abstract Background The voltage gated sodium channel Nav 1.8 has a highly restricted expression pattern to predominantly nociceptive peripheral sensory neurones. Behaviourally Nav 1.8-null mice show an increased acute pain threshold to noxious mechanical pressure and also deficits in inflammatory and visceral, but not neuropathic pain. Here we have made in vivo electrophysiology recordings of dorsal horn neurones in intact anaesthetised Nav 1.8-null mice, in response to a wide range of stimuli to further the understanding of the functional roles of Nav 1.8 in pain transmission from the periphery to the spinal cord. Results Nav 1.8-null mice showed marked deficits in the coding by dorsal horn neurones to mechanical, but not thermal, -evoked responses over the non-noxious and noxious range compared to littermate controls. Additionally, responses evoked to other stimulus modalities were also significantly reduced in Nav 1.8-null mice where the reduction observed to pinch > brush. The occurrence of ongoing spontaneous neuronal activity was significantly less in mice lacking Nav 1.8 compared to control. No difference was observed between groups in the evoked activity to electrical activity of the peripheral receptive field. Conclusion This study demonstrates that deletion of the sodium channel Nav 1.8 results in stimulus-dependent deficits in the dorsal horn neuronal coding to mechanical, but not thermal stimuli applied to the neuronal peripheral receptive field. This implies that Nav 1.8 is either responsible for, or associated with proteins involved in mechanosensation.

An improved protocol for efficient engraftment in NOD/LTSZ-SCIDIL-2Rγnull mice allows HIV replication and development of anti-HIV immune responses.

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Maneesh Singh

Full Text Available Cord blood hematopoietic progenitor cells (CB-HPCs transplanted immunodeficient NOD/LtsZ-scidIL2Rγ(null (NSG and NOD/SCID/IL2Rγ(null (NOG mice need efficient human cell engraftment for long-term HIV-1 replication studies. Total body irradiation (TBI is a classical myeloablation regimen used to improve engraftment levels of human cells in these humanized mice. Some recent reports suggest the use of busulfan as a myeloablation regimen to transplant HPCs in neonatal and adult NSG mice. In the present study, we further ameliorated the busulfan myeloablation regimen with fresh CB-CD34+cell transplantation in 3-4 week old NSG mice. In this CB-CD34+transplanted NSG mice engraftment efficiency of human CD45+cell is over 90% in peripheral blood. Optimal engraftment promoted early and increased CD3+T cell levels, with better lymphoid tissue development and prolonged human cell chimerism over 300 days. These humanized NSG mice have shown long-lasting viremia after HIV-1JRCSF and HIV-1Bal inoculation through intravenous and rectal routes. We also saw a gradual decline of the CD4+T cell count, widespread immune activation, up-regulation of inflammation marker and microbial translocation after HIV-1 infection. Humanized NSG mice reconstituted according to our new protocol produced, moderate cellular and humoral immune responses to HIV-1 postinfection. We believe that NSG mice reconstituted according to our easy to use protocol will provide a better in vivo model for HIV-1 replication and anti-HIV-1 therapy trials.

PENINGKATAN AKTIFITAS DAN HASIL BELAJAR DENGAN METODE PROBLEM BASIC LEARNING (PBL PADA MATA PELAJARAN TUNE UP MOTOR BENSIN SISWA KELAS XI DI SMK INSAN CENDEKIA TURI SLEMAN TAHUN AJARAN 2015/2016

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Hermawan Budi Santoso

2017-06-01

Full Text Available The aim of this research is to know the increase of learning activityand result using Problem Based Learning in motorbike gasoline Tune-up lesson for students in grade XI SMK Insan Cendekia Sleman. This research is a kind of action research, which in the process applying the PBL method. This research has 4 steps, which are planning, application, observation and reflection. The observation of students activity in applying PBL learning is done by going to the class directly while the learning process is still ongoing. While, the result of student learning is measured by first assessment and final assessment. The result shows that after PBL method which is given to the students there is an increase of learning activity in amount 60%, while the increase of learning result in time of observation is approximately getting 6,5 for average mark First cycle, the average mark is 6,5, while for the second cycle 6,8 and 7,3 for third cycle. These evidences show PBL method application can increase the learning activity and result using Problem Based Learning in motorbike gasoline Tune-up lesson for students in grade XI SMK Insan Cendekia Sleman

Dysregulated Intrahepatic CD4+ T-Cell Activation Drives Liver Inflammation in Ileitis-Prone SAMP1/YitFc MiceSummary

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Sara Omenetti

2015-07-01

Full Text Available Background & Aims: Liver inflammation is a common extraintestinal manifestation of inflammatory bowel disease (IBD, but whether liver involvement is a consequence of a primary intestinal defect or results from alternative pathogenic processes remains unclear. Therefore, we sought to determine the potential pathogenic mechanism(s of concomitant liver inflammation in an established murine model of IBD. Methods: Liver inflammation and immune cell subsets were characterized in ileitis-prone SAMP1/YitFc (SAMP and AKR/J (AKR control mice, lymphocyte-depleted SAMP (SAMPxRag-1−/−, and immunodeficient SCID recipient mice receiving SAMP or AKR donor CD4+ T cells. Proliferation and suppressive capacity of CD4+ T-effector (Teff and T-regulatory (Treg cells from gut-associated lymphoid tissue (GALT and livers of SAMP and AKR mice were measured. Results: Surprisingly, prominent inflammation was detected in 4-week-old SAMP livers before histologic evidence of ileitis, whereas both disease phenotypes were absent in age-matched AKR mice. SAMP liver disease was characterized by abundant infiltration of lymphocytes, required for hepatic inflammation to occur, a TH1-skewed environment, and phenotypically activated CD4+ T cells. SAMP intrahepatic CD4+ T cells also had the ability to induce liver and ileal inflammation when adoptively transferred into SCID recipients, whereas GALT-derived CD4+ T cells produced milder ileitis but not liver inflammation. Interestingly, SAMP intrahepatic CD4+ Teff cells showed increased proliferation compared with both SAMP GALT- and AKR liver-derived CD4+ Teff cells, and SAMP intrahepatic Tregs were decreased among CD4+ T cells and impaired in in vitro suppressive function compared with AKR. Conclusions: Activated intrahepatic CD4+ T cells induce liver inflammation and contribute to experimental ileitis via locally impaired hepatic immunosuppressive function. Keywords: Hepatic CD4+ T Cells, IBD-Associated Liver

Development of a Murine Model for Aerosolized Ebolavirus Infection Using a Panel of Recombinant Inbred Mice

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Malak Kotb

2012-12-01

Full Text Available Countering aerosolized filovirus infection is a major priority of biodefense research.  Aerosol models of filovirus infection have been developed in knock-out mice, guinea pigs and non-human primates; however, filovirus infection of immunocompetent mice by the aerosol route has not been reported.  A murine model of aerosolized filovirus infection in mice should be useful for screening vaccine candidates and therapies.  In this study, various strains of wild-type and immunocompromised mice were exposed to aerosolized wild-type (WT or mouse-adapted (MA Ebola virus (EBOV.  Upon exposure to aerosolized WT-EBOV, BALB/c, C57BL/6 (B6, and DBA/2 (D2 mice were unaffected, but 100% of severe combined immunodeficiency (SCID and 90% of signal transducers and activators of transcription (Stat1 knock-out (KO mice became moribund between 7–9 days post-exposure (dpe.  Exposure to MA-EBOV caused 15% body weight loss in BALB/c, but all mice recovered.  In contrast, 10–30% lethality was observed in B6 and D2 mice exposed to aerosolized MA-EBOV, and 100% of SCID, Stat1 KO, interferon (IFN-γ KO and Perforin KO mice became moribund between 7–14 dpe. In order to identify wild-type, inbred, mouse strains in which exposure to aerosolized MA-EBOV is uniformly lethal, 60 BXD (C57BL/6 crossed with DBA/2 recombinant inbred (RI and advanced RI (ARI mouse strains were exposed to aerosolized MA-EBOV, and monitored for disease severity. A complete spectrum of disease severity was observed. All BXD strains lost weight but many recovered. However, infection was uniformly lethal within 7 to 12 days post-exposure in five BXD strains.  Aerosol exposure of these five BXD strains to 10-fold less MA-EBOV resulted in lethality ranging from 0% in two strains to 90–100% lethality in two strains.  Analysis of post-mortem tissue from BXD strains that became moribund and were euthanized at the lower dose of MA-EBOV, showed liver damage in all mice as well as lung lesions in

The cytoskeletal inhibitors latrunculin A and blebbistatin exert antitumorigenic properties in human hepatocellular carcinoma cells by interfering with intracellular HuR trafficking

International Nuclear Information System (INIS)

Doller, Anke; Badawi, Amel; Schmid, Tobias; Brauß, Thilo; Pleli, Thomas; Meyer zu Heringdorf, Dagmar; Piiper, Albrecht; Pfeilschifter, Josef; Eberhardt, Wolfgang

2015-01-01

The impact of the RNA-binding protein HuR for the post-transcriptional deregulation of tumor-relevant genes is well established. Despite of elevations in HuR expression levels, an increase in cytoplasmic HuR abundance in many cases correlates with a high grade of malignancy. Here, we demonstrated that administration of the actin-depolymerizing macrolide latrunculin A, or blebbistatin, an inhibitor of myosin II ATPase activity, caused a dose- and time-dependent reduction in the high cytoplasmic HuR content of HepG2 and Huh7 hepatocellular carcinoma (HCC) cells. Subcellular fractionation revealed that in addition, both inhibitors strongly attenuated cytoskeletal and membrane-bound HuR abundance and conversely increased the HuR amount in nuclear cell fractions. Concomitant with changes in intracellular HuR localization, both cytoskeletal inhibitors markedly decreased the half-lives of cyclooxygenase-2 (COX-2), cyclin A and cyclin D 1 encoding mRNAs resulting in a significant reduction in their expression levels in HepG2 cells. Importantly, a similar reduction in the expression of these HuR targets was achieved by a RNA interference (RNAi)-mediated knockdown of either HuR or nonmuscle myoin IIA. Using polysomal fractionation, we further demonstrate that the decrease in cytoplasmic HuR by latrunculin A or blebbistatin is accompanied by a marked change in the allocation of HuR and its mRNA cargo from polysomes to ribonucleoprotein (RNP) particles. Functionally, the basal migration and prostaglandin E 2 synthesis are similarly impaired in inhibitor-treated and stable HuR-knockdown HepG2 cells. Our data demonstrate that interfering with the actomyosin-dependent HuR trafficking may comprise a valid therapeutic option for antagonizing pathologic posttranscriptional gene expression by HuR and furthermore emphasize the potential benefit of HuR inhibitory strategies for treatment of HCC. - Highlights: • We tested the effects of latrunculin A and blebbistatin on different Hu

Managing PBL difficulties in an industrial engineering and management program

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Anabela Alves

2016-08-01

Full Text Available Purpose: Project-Based Learning (PBL is considered to be an active learning methodology which can be used to develop both technical and transversal competences in engineering programs. This methodology demands a great deal of work effort from the students and also from the teachers and it requires a meticulous plan and a well-managed project as well. These activities go far beyond the normal activities in traditional lectures, enabling to outpace the difficulties that spur along the way that may be both complex and demotivating. This methodology has been implemented in the Integrated Master Degree on Industrial Engineering and Management (IEM, at one public university in Portugal, since the 2004/2005 academic year. The aim of this paper is to identify and discuss the main difficulties of the implementation of PBL, mainly from the teachers’ perspectives. Additionally, some effective strategies will be recommended to overcome such difficulties. Design/methodology/approach: The perceptions of the teachers were collected through a survey based on six main themes. The participants in the study include eight teachers from the five courses of the first semester of the first year of the IEM program involved in the 2012/2013 and 2013/2014 editions. Findings: Integration of courses in the project; student assessment; growing number of students in each team and the need of physical spaces for them; and compartmentalized knowledge has emerged as the main difficulties. To overcome these difficulties some key strategies were recommended. Originality/value: A new perspective based on course teachers' views and experiences will deepen the understanding of the problems and provide inputs for the development of strategies that may improve the effectiveness of PBL and introduce changes for its successful implementation. These strategies are intended to be transferable to other contexts, as most of the problems and constraints are common to other active learning

Managing PBL difficulties in an industrial engineering and management program

International Nuclear Information System (INIS)

Alves, A.; Sousa, R.; Moreira, F.; Carvalho, M.A.; Cardoso, E.; Pimenta, P.; Malheiro, T.; Brito, I.; Fernandes, S.; Mesquita, D.

2016-01-01

Project-Based Learning (PBL) is considered to be an active learning methodology which can be used to develop both technical and transversal competences in engineering programs. This methodology demands a great deal of work effort from the students and also from the teachers and it requires a meticulous plan and a well-managed project as well. These activities go far beyond the normal activities in traditional lectures, enabling to outpace the difficulties that spur along the way that may be both complex and demotivating. This methodology has been implemented in the Integrated Master Degree on Industrial Engineering and Management (IEM), at one public university in Portugal, since the 2004/2005 academic year. The aim of this paper is to identify and discuss the main difficulties of the implementation of PBL, mainly from the teachers’ perspectives. Additionally, some effective strategies will be recommended to overcome such difficulties. Design/methodology/approach: The perceptions of the teachers were collected through a survey based on six main themes. The participants in the study include eight teachers from the five courses of the first semester of the first year of the IEM program involved in the 2012/2013 and 2013/2014 editions. Findings: Integration of courses in the project; student assessment; growing number of students in each team and the need of physical spaces for them; and compartmentalized knowledge has emerged as the main difficulties. To overcome these difficulties some key strategies were recommended. Originality/value: A new perspective based on course teachers' views and experiences will deepen the understanding of the problems and provide inputs for the development of strategies that may improve the effectiveness of PBL and introduce changes for its successful implementation. These strategies are intended to be transferable to other contexts, as most of the problems and constraints are common to other active learning approaches. (Author)

Managing PBL difficulties in an industrial engineering and management program

Energy Technology Data Exchange (ETDEWEB)

Alves, A.; Sousa, R.; Moreira, F.; Carvalho, M.A.; Cardoso, E.; Pimenta, P.; Malheiro, T.; Brito, I.; Fernandes, S.; Mesquita, D.

2016-07-01

Project-Based Learning (PBL) is considered to be an active learning methodology which can be used to develop both technical and transversal competences in engineering programs. This methodology demands a great deal of work effort from the students and also from the teachers and it requires a meticulous plan and a well-managed project as well. These activities go far beyond the normal activities in traditional lectures, enabling to outpace the difficulties that spur along the way that may be both complex and demotivating. This methodology has been implemented in the Integrated Master Degree on Industrial Engineering and Management (IEM), at one public university in Portugal, since the 2004/2005 academic year. The aim of this paper is to identify and discuss the main difficulties of the implementation of PBL, mainly from the teachers’ perspectives. Additionally, some effective strategies will be recommended to overcome such difficulties. Design/methodology/approach: The perceptions of the teachers were collected through a survey based on six main themes. The participants in the study include eight teachers from the five courses of the first semester of the first year of the IEM program involved in the 2012/2013 and 2013/2014 editions. Findings: Integration of courses in the project; student assessment; growing number of students in each team and the need of physical spaces for them; and compartmentalized knowledge has emerged as the main difficulties. To overcome these difficulties some key strategies were recommended. Originality/value: A new perspective based on course teachers' views and experiences will deepen the understanding of the problems and provide inputs for the development of strategies that may improve the effectiveness of PBL and introduce changes for its successful implementation. These strategies are intended to be transferable to other contexts, as most of the problems and constraints are common to other active learning approaches. (Author)

A pandemic influenza H1N1 live vaccine based on modified vaccinia Ankara is highly immunogenic and protects mice in active and passive immunizations.

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Annett Hessel

Full Text Available BACKGROUND: The development of novel influenza vaccines inducing a broad immune response is an important objective. The aim of this study was to evaluate live vaccines which induce both strong humoral and cell-mediated immune responses against the novel human pandemic H1N1 influenza virus, and to show protection in a lethal animal challenge model. METHODOLOGY/PRINCIPAL FINDINGS: For this purpose, the hemagglutinin (HA and neuraminidase (NA genes of the influenza A/California/07/2009 (H1N1 strain (CA/07 were inserted into the replication-deficient modified vaccinia Ankara (MVA virus--a safe poxviral live vector--resulting in MVA-H1-Ca and MVA-N1-Ca vectors. These live vaccines, together with an inactivated whole virus vaccine, were assessed in a lung infection model using immune competent Balb/c mice, and in a lethal challenge model using severe combined immunodeficient (SCID mice after passive serum transfer from immunized mice. Balb/c mice vaccinated with the MVA-H1-Ca virus or the inactivated vaccine were fully protected from lung infection after challenge with the influenza H1N1 wild-type strain, while the neuraminidase virus MVA-N1-Ca induced only partial protection. The live vaccines were already protective after a single dose and induced substantial amounts of neutralizing antibodies and of interferon-gamma-secreting (IFN-gamma CD4- and CD8 T-cells in lungs and spleens. In the lungs, a rapid increase of HA-specific CD4- and CD8 T cells was observed in vaccinated mice shortly after challenge with influenza swine flu virus, which probably contributes to the strong inhibition of pulmonary viral replication observed. In addition, passive transfer of antisera raised in MVA-H1-Ca vaccinated immune-competent mice protected SCID mice from lethal challenge with the CA/07 wild-type virus. CONCLUSIONS/SIGNIFICANCE: The non-replicating MVA-based H1N1 live vaccines induce a broad protective immune response and are promising vaccine candidates for

Pengembangan Perangkat Pembelajaran Matematika Berbasis Problem Based Learning (PBL untuk Meningkatkan Kemampuan Pemecahan Masalah Peserta Didik Kelas VIII

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Rizza Yustianingsih

2017-09-01

that can be facilitate learners to improve solving of mathematical problems ability and student’s activities to learn. From that case, to be underlying to do development learning tools of mathematics, there are plan lesson plan (RPP and student’s worksheet (LKPD on Problem Based Learning (PBL, which can provide a learning experience to learn problem solving and can provide a good potential effects on student’s activities during the learning proccess. Data were collected through observation, questionnaires, interviews, and test problem solving abilities. The subjects of this research are students grade VIII SMP N 3 Sawahlunto. This research development is used Plomp mode consists of phase preliminary research, prototype phase, and assessment phase. Based on the data analysis result, it was showed that the learning equipment based on  PBL has fulfilled valid criteria in term of content and construct. The lesson equipment has been considered as practical in terms of implementation and the efficiency of time use by teachers and students. The lesson equipment has also been effective in terms of process  the presentation mastery learning students after using the device based learning problem-based learning is greater than or equal to 75% while in terms of results the average student has been active in the learning. Based on these results, it can be concluded that the mathematics lesson equipment based on PBL which was conducted to student's of class VIII was valid, practical, and effective. Keyword. Mathematics Lesson Equipment, Problem Solving, PBL.

Problem-Based Learning (PBL and Student Interest in STEM Careers: The Roles of Motivation and Ability Beliefs

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Melanie LaForce

2017-12-01

Full Text Available Amid growing concerns about the future of the U.S. economy and workforce, educators and policymakers alike have increasingly emphasized the need to expand the number of students interested in, qualified for and actually pursuing careers in science, technology, engineering and mathematics (STEM. The current study draws on survey responses from a sample of 3852 high school students at inclusive STEM schools across the U.S. to investigate how project- and problem-based learning (PBL may work to address this need. Multivariate regression results indicate that student ratings of PBL are associated with interest in pursuing a career in STEM, as well as with intrinsic motivation for science and students’ ability beliefs for both science and math. Further, mediation analysis using Hayes’ (2014 MEDIATE macro suggests that science intrinsic motivation and ability beliefs mediate the relationship between perceived PBL experiences and student interest in a future STEM career (IFSC. Our results highlight the important potential of PBL for increasing student STEM attitudes and interest in future STEM careers. As one of the only large-scale quantitative analyses of its kind, this study provides critical information for educators, school administrators and policymakers as they continue to seek effective ways of encouraging students to pursue STEM careers.

Analysis Critical Thinking Stage of Eighth Grade in PBL-Scaffolding Setting To Solve Mathematical Problems

OpenAIRE

Nur Aisyah Isti; Arief Agoestanto; Ary Woro Kurniasih

2017-01-01

The purpose of this research was described critical thinking stage of students grade VIII in setting PBL and scaffolding to solve mathematics problems. Critical thinking stage consists of clarification, assesment, inference, and strategy/tactics. The subject were teo students in the level of capacity to think critical (uncritical, less critical, quite critical, and critical). So that this research subject was 8 students in VIII A One State Junior High School of Temanggung. The result showed a...

Understanding `green chemistry' and `sustainability': an example of problem-based learning (PBL)

Science.gov (United States)

Günter, Tuğçe; Akkuzu, Nalan; Alpat, Şenol

2017-10-01

Background: This study uses problem-based learning (PBL) to ensure that students comprehend the significance of green chemistry better by experiencing the stages of identifying the problem, developing hypotheses, and providing solutions within the problem-solving process.

Thyroid epithelial cell hyperplasia in IFN-gamma deficient NOD.H-2h4 mice.

Science.gov (United States)

Yu, Shiguang; Sharp, Gordon C; Braley-Mullen, Helen

2006-01-01

The role of inflammatory cells in thyroid epithelial cell (thyrocyte) hyperplasia is unknown. Here, we demonstrate that thyrocyte hyperplasia in IFN-gamma-/- NOD.H-2h4 mice has an autoimmune basis. After chronic exposure to increased dietary iodine, 60% of IFN-gamma-/- mice had severe thyrocyte hyperplasia with minimal or moderate lymphocyte infiltration, and thyroid dysfunction with reduced serum T4. All mice produced anti-thyroglobulin autoantibody. Some wild-type NOD.H-2h4 mice had isolated areas of thyrocyte hyperplasia with predominantly lymphocytic infiltration, whereas IL-4-/- and 50% of wild-type NOD.H-2h4 mice developed lymphocytic thyroiditis but no thyrocyte hyperplasia. Both thyroid infiltrating inflammatory cells and environmental factors (iodine) were required to induce thyrocyte hyperplasia. Splenocytes from IFN-gamma-/- mice with thyrocyte hyperplasia, but not splenocytes from naïve IFN-gamma-/- mice, induced hyperplasia in IFN-gamma-/- NOD.H-2h4.SCID mice. These results may provide clues for understanding the mechanisms underlying development of epithelial cell hyperplasia not only in thyroids but also in other tissues and organs.

Evaluation of two MM5-PBL parameterization for solar radiation and temperature estimation in the South-Eastern area of the Iberian Peninsula

International Nuclear Information System (INIS)

Ruiz-Arias, J.A.; Pozo-Vasquez, D.; Sanchez-Sanchez, N.; Hayas-Barru, A.; Tovar-Pescador, J.; Montavez, J.P.

2008-01-01

We study the relative performance of two different MM5-PBL parametrizations (Blackadar and MRF) simulating hourly values of solar irradiance and temperature in the south-eastern part of the Iberian Peninsula. The evaluation was carried out throughout the different season of the year 2005 and for three different sky conditions: clear-sky, broken-clouds and overcast conditions. Two integrations, one per PBL parameterization, were carried out for every sky condition and season of the year and results were compared with observational data. Overall, the MM5 model, both using the Blackadar or MRF PBL parameterization, revealed to be a valid tool to estimate hourly values of solar radiation and temperature over the study area. The influence of the PBL parameterization on the model estimates was found to be more important for the solar radiation than for the temperature and highly dependent on the season and sky conditions. Particularly, a detailed analysis revealed that, during broken-clouds conditions, the ability of the model to reproduce hourly changes in the solar radiation strongly depends upon the selected PBL parameterization. Additionally, it was found that solar radiation RMSE values are about one order of magnitude higher during broken-clouds and overcast conditions compared to clear-sky conditions. For the temperature, the two PBL parameterizations provide very similar estimates. Only under overcast conditions and during the autumn, the MRF provides significantly better estimates.

The cytoskeletal inhibitors latrunculin A and blebbistatin exert antitumorigenic properties in human hepatocellular carcinoma cells by interfering with intracellular HuR trafficking

Energy Technology Data Exchange (ETDEWEB)

Doller, Anke; Badawi, Amel [Pharmazentrum Frankfurt/ZAFES, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main (Germany); Schmid, Tobias; Brauß, Thilo [Institut für Biochemie I (Pathobiochemie), Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main (Germany); Pleli, Thomas [Medizinische Klinik 1, Schwerpunkt Gastroenterologie und Hepatologie, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main (Germany); Meyer zu Heringdorf, Dagmar [Pharmazentrum Frankfurt/ZAFES, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main (Germany); Piiper, Albrecht [Medizinische Klinik 1, Schwerpunkt Gastroenterologie und Hepatologie, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main (Germany); Pfeilschifter, Josef [Pharmazentrum Frankfurt/ZAFES, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main (Germany); Eberhardt, Wolfgang, E-mail: w.eberhardt@em.uni-frankfurt.de [Pharmazentrum Frankfurt/ZAFES, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main (Germany)

2015-01-01

The impact of the RNA-binding protein HuR for the post-transcriptional deregulation of tumor-relevant genes is well established. Despite of elevations in HuR expression levels, an increase in cytoplasmic HuR abundance in many cases correlates with a high grade of malignancy. Here, we demonstrated that administration of the actin-depolymerizing macrolide latrunculin A, or blebbistatin, an inhibitor of myosin II ATPase activity, caused a dose- and time-dependent reduction in the high cytoplasmic HuR content of HepG2 and Huh7 hepatocellular carcinoma (HCC) cells. Subcellular fractionation revealed that in addition, both inhibitors strongly attenuated cytoskeletal and membrane-bound HuR abundance and conversely increased the HuR amount in nuclear cell fractions. Concomitant with changes in intracellular HuR localization, both cytoskeletal inhibitors markedly decreased the half-lives of cyclooxygenase-2 (COX-2), cyclin A and cyclin D{sub 1} encoding mRNAs resulting in a significant reduction in their expression levels in HepG2 cells. Importantly, a similar reduction in the expression of these HuR targets was achieved by a RNA interference (RNAi)-mediated knockdown of either HuR or nonmuscle myoin IIA. Using polysomal fractionation, we further demonstrate that the decrease in cytoplasmic HuR by latrunculin A or blebbistatin is accompanied by a marked change in the allocation of HuR and its mRNA cargo from polysomes to ribonucleoprotein (RNP) particles. Functionally, the basal migration and prostaglandin E{sub 2} synthesis are similarly impaired in inhibitor-treated and stable HuR-knockdown HepG2 cells. Our data demonstrate that interfering with the actomyosin-dependent HuR trafficking may comprise a valid therapeutic option for antagonizing pathologic posttranscriptional gene expression by HuR and furthermore emphasize the potential benefit of HuR inhibitory strategies for treatment of HCC. - Highlights: • We tested the effects of latrunculin A and blebbistatin on

Metabolic aspects of growth in HU-treated crown-gall tissue cultures. II. Helianthus annuus

Directory of Open Access Journals (Sweden)

Aldona Rennert

2015-01-01

Full Text Available The dynamics of growth and changes in nucleic acid and protein contents in sunflower calluses and tumours cultured in hydroxyurea (HU containing media were examined. HU-induced changes in healthy tissues ran in parallel always in the same direction, in tumourous ones however an uncoupling between DNA synthesis and tissue growth on one hand and RNA and protein synthesis on the other took place. A detailed analysis of the results allows to suppose that the specific activity of HU on tumourous tissue could be an index of: 1 quantitative disturbances in its genes function (2 degree of the lass of sensitivity to the factors of regulation.

Effets des sels organiques de tributyletain sur l'huître adulte Crassostrea gigas

OpenAIRE

Heral, Maurice; Alzieu, Claude; Caux, O.; Razet, Daniel; Garnier, Jacqueline

1983-01-01

La toxicité des composés organostanniques a été mise en évidence à l'égard de l'huître Crassostrea gigas tant aux stades larvaires (His & Robert, 1980) que chez l'adulte (Alzieu & al., 1980, 1981). Parallèlement ces mêmes auteurs ont montré l'accumulation d'étain dans les huîtres contaminées expérimentalement ainsi que le rôle que peut jouer le fluorure de TBT dans la perturbation de la croissance (Héral & al. 1981) et dans la malformation de la coquille des huîtres (Alzieu & al., 1981). Dans...

Proton pump inhibitors while belonging to the same family of generic drugs show different anti-tumor effect.

Science.gov (United States)

Lugini, Luana; Federici, Cristina; Borghi, Martina; Azzarito, Tommaso; Marino, Maria Lucia; Cesolini, Albino; Spugnini, Enrico Pierluigi; Fais, Stefano

2016-08-01

Tumor acidity represents a major cause of chemoresistance. Proton pump inhibitors (PPIs) can neutralize tumor acidity, sensitizing cancer cells to chemotherapy. To compare the anti-tumor efficacy of different PPIs in vitro and in vivo. In vitro experiments PPIs anti-tumor efficacy in terms of cell proliferation and cell death/apoptosis/necrosis evaluation were performed. In vivo PPIs efficacy experiments were carried out using melanoma xenograft model in SCID mice. Lansoprazole showed higher anti-tumor effect when compared to the other PPIs. The lansoprazole effect lasted even upon drug removal from the cell culture medium and it was independent from the lipophilicity of the PPIs formulation. These PPIs have shown different anti-tumoral efficacy, and the most effective at low dose was lansoprazole. The possibility to contrast tumor acidity by off-label using PPIs opens a new field of oncology investigation.

Integration of Sustainability in Engineering Education: Why Is PBL an Answer?

Science.gov (United States)

Guerra, Aida

2017-01-01

Purpose: Education for sustainable development (ESD) is one of the challenges engineering education currently faces. Engineering education needs to revise and change its curriculum to integrate ESD principles and knowledge. Problem based learning (PBL) has been one of the main learning pedagogies used to integrate sustainability in engineering…

The Impact of PBL on Transferable Skills Development in Management Education

Science.gov (United States)

Carvalho, Ana

2016-01-01

Attention to transferable skills is growing in higher education. Problem-based learning (PBL) is increasingly used in management education for its promising potential to, amongst others, promote transferable skills, including problem-solving, critical thinking and teamwork skills. However, this relationship is seldom assessed. In this study, I use…

Drug Transporter Expression and Activity in Human Hepatoma HuH-7 Cells

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Elodie Jouan

2016-12-01

Full Text Available Human hepatoma cells may represent a valuable alternative to the use of human hepatocytes for studying hepatic drug transporters, which is now a regulatory issue during drug development. In the present work, we have characterized hepatic drug transporter expression, activity and regulation in human hepatoma HuH-7 cells, in order to determine the potential relevance of these cells for drug transport assays. HuH-7 cells displayed notable multidrug resistance-associated protein (MRP activity, presumed to reflect expression of various hepatic MRPs, including MRP2. By contrast, they failed to display functional activities of the uptake transporters sodium taurocholate co-transporting polypeptide (NTCP, organic anion-transporting polypeptides (OATPs and organic cation transporter 1 (OCT1, and of the canalicular transporters P-glycoprotein and breast cancer resistance protein (BCRP. Concomitantly, mRNA expressions of various sinusoidal and canalicular hepatic drug transporters were not detected (NTCP, OATP1B1, organic anion transporter 2 (OAT2, OCT1 and bile salt export pump or were found to be lower (OATP1B3, OATP2B1, multidrug and toxin extrusion protein 1, BCRP and MRP3 in hepatoma HuH-7 cells than those found in human hepatocytes, whereas other transporters such as OAT7, MRP4 and MRP5 were up-regulated. HuH-7 cells additionally exhibited farnesoid X receptor (FXR- and nuclear factor erythroid 2-related factor 2 (Nrf2-related up-regulation of some transporters. Such data indicate that HuH-7 cells, although expressing rather poorly some main hepatic drug transporters, may be useful for investigating interactions of drugs with MRPs, notably MRP2, and for studying FXR- or Nrf2-mediated gene regulation.

Abundances of the planetary nebula Hu 1-2

NARCIS (Netherlands)

Pottasch, [No Value; Hyung, S; Aller, LH; Beintema, DA; Bernard-Salas, J; Feibelman, WA; Klockner, HR

The ISO and IUE spectra of the "elliptical" nebula Hu 1-2 are presented. These spectra are combined with new, high resolution spectra in the visual wavelength region to obtain a complete, extinction corrected, spectrum. The chemical composition of the nebula is then calculated and compared to

Ionizing radiation-induced DNA double-strand break and repair assessed by γ-H2AX foci analysis in neurons in mice

International Nuclear Information System (INIS)

Dong Xiaorong; Wu Gang; Ruebe Claudia; Ruebe Christian

2009-01-01

Objective: To investigate if the γ-H2AX foci is a precise index for the DSB formation and repair in mature neurons of brain in vivo after clinically relevant doses irradiation. Methods: For the DSB formation experiment, the mature neurons in the neocortex of brain tissue of C57BL/6 mice were analyzed at 10 rain after whole-body irradiation with 0.1, 0.5 and 1.0 Gy. For the DSB repair kinetics experiment, the mature neurons in the neocortex of brain tissue of repair-proficient (C57BL/6 mice) and repair-deficient mouse strains (BALB/c, A-T and SCID mice) were analyzed at 0.5, 2.5, 5, 24 and 48 h after whole-body irradiation with 2 Gy. The mature neurons in the neocortex of brain tissue of sham-irradiated mice of each strain served as controls. γ-H2AX immunohistochemistry and γ-H2AX and NeuN double immunofluorescence analysis was used to measure DSBs formation and repair in the mature neurons in the neocortex of brain tissue of the different mouse strains. Results: For the DSB formation experiment, γ-H2AX foci levels with a clear linear close correlation and very low backgrounds in the nuclei in the neocortex of brain tissue were observed. Scoring the loss of γ-H2AX foci allowed us to verify the different, genetically determined DSB repair deficiencies, including the minor impairment of BALB/c mice. Repair-proficient C57BL/6 mice exhibited the fastest decrease in foci number with time, and displayed low levels of residual damage at 24 h and 48 h post-irradiation. In contrast, SCID mice showed highly increased γ-H2AX foci levels at all repair times (0.5 h to 48 h) while A-T mice exhibited a lesser defect which was most significant at later repair times (≥ 5 h). Radiosensitive BALB/c mice exhibited slightly elevated foci numbers compared with C57BL/6 mice at 5 h and 24 h but not at 48 h post-irradiation. Conclusion: Quantifying the γ-H2AX foci in normal tissue represents a sensitivie tool for the detection of induction and repair of radiation-induced DSBs at

Preclinical evaluation of human T lymphocytes in RAG2-/-γc-/- mice

NARCIS (Netherlands)

Rijn, R.S. van

2006-01-01

This thesis describes the development and application of a new model for the preclinical study of human T cells by transfer of huPBMCs into RAG2-/-γc-/- immunodeficient mice. The ultimate goal of treating patients with a malignancy is to eradicate the malignant cells, while keeping hold of damage to

Implementation of team-based learning in year 1 of a PBL based medical program: a pilot study.

Science.gov (United States)

Burgess, Annette; Ayton, Tom; Mellis, Craig

2016-02-04

A traditional and effective form of teaching within medical education has been Problem Based Learning (PBL). However, this method of teaching is resource intensive, normally requiring one tutor for every ten students. Team-based learning (TBL) has gained recent popularity in medical education, and can be applied to large groups of up to 100 students. TBL makes use of the advantages of small group teaching and learning, but in contrast to PBL, does not need large numbers of teachers. This study sought to explore the efficacy of using TBL in place of PBL in Year 1 of a medical program. In Year 1 of the medical program, two iterations of TBL, with 20 students, were run following four iterations of PBL within the Cardiology teaching block. Student feedback following PBL and TBL was collected by questionnaire, using closed and open ended questions. Additionally, individual and team tests were held at the beginning of each TBL class, and results of each week were compared. All students (n = 20) participated in the test in week 1, and 18/20 students participated in week 2. In total, 19/20 (95%) of students completed the questionnaires regarding their PBL and TBL experiences. The use of small groups, the readiness assurance tests, immediate feedback from an expert clinician, as well as time efficiency were all aspects of the TBL experience that students found positive. The clinical problem-solving activity, however, was considered to be less effective with TBL. There was a significant improvement (p = 0.004) in students' score from the week 1 assessment (median = 2) to the week 2 (median = 3.5) assessment. Interestingly, all teams but one (Team 1) achieved a lower score on their second week assessment than on their first. However, the lowest performing team in week 1 outperformed all other teams in week 2. Students favoured many aspects of the TBL process, particularly motivation to do the pre-reading, and better engagement in the process. Additionally, the

HuR binds to a single site on the C/EBPβ mRNA of 3T3-L1 adipocytes

International Nuclear Information System (INIS)

Jones, Heath; Carver, Melinda; Pekala, Phillip H.

2007-01-01

HuR is a ligand for nuclear mRNAs containing adenylate-uridylate rich elements in the 3'-untranslated region. Once bound to the mRNA, HuR is recognized by adapter proteins which then facilitate nuclear export of the complex. In the cytosol HuR is thought to function to control stability and translation of its ligand message. In the 3T3-L1 cells HuR is constitutively expressed and localized predominantly to the nucleus in the preadipocytes. However within 30 min of exposure to the differentiation stimulus, the HuR content in the cytosol increases consistent with HuR regulating the availability of relevant mRNAs for translation. Using in vitro RNA gel shifts, we have demonstrated that the C/EBPβ message is a ligand for HuR and that the single binding site is an adenylate-uridylate rich element in the 3'-untranslated region

人格障碍定式临床会谈量表(第2版)与人格诊断问卷对比分析%A study on the comparability of SCID-Ⅱ and PDQ-4

Institute of Scientific and Technical Information of China (English)

戴云飞; 肖泽萍

2008-01-01

Objective To study the comparability of two personality diagnostic instruments(SCID-Ⅱ and PDQ-4)in psychiatric patients. Methods One hundred and twelve mental disorder patients were investigated with the SCID-Ⅱ and PDQ-4. Results 1)Significant differences were found between groups(dividing by total scores on PDQ-4)by means of SCID-Ⅱ interviews(P＜0. 0 1). 2)Categorical personality disorder(PD)groups by means of SCID-Ⅱ interviews had hisher scores on PDQ-4 than their related non-PD groups. 3)For agreement on categorical diagnoses between SCID-Ⅱ and PDQ-4, the correlation coefficients varied from 0. 17 to 0. 57. Except for antisocial PD(r=0. 57), the others had poor-fair coefficients, as r＜0. 50. Conclusions In general, there is some correlation between SCID-Ⅱ and PDQ-4. Low agreement between PDQ-4 and SCID-Ⅱ is observed for categorical PD evaluations. Thus, PDQ-4 can't be a substitute tool for SCID-Ⅱ.%目的 探讨人格诊断问卷人格障碍定式临床会谈量表(SCID-Ⅱ)(第2版)和PDQ-4两种工具的相关性和差异.方法 对112例精神障碍患者进行量表评定及相关的统计分析.结果 (1)按PDQ-4总分分组,组间根据SCID-Ⅱ诊断为人格障碍的例数,其差异具有显著性(P＜0.01).(2)SCID-Ⅱ各型人格障碍组PDQ-4得分均高于无该型人格障碍组.(3)对于人格障碍的分型诊断,SCID-Ⅱ与PDQ-4的相关系数r为0.17～0.57,除反社会型r=0.57外,其余各型相关系数(r＜0.50).结论 总体上SCID-Ⅱ与PDQ-4具有一定的相关性,但PDQ-4与SCID-Ⅱ对人格障碍的分型诊断一致性较差,PDQ-4不能代替定式问卷SCID-Ⅱ来诊断人格障碍.

Dental students' perception of their approaches to learning in a PBL programme.

Science.gov (United States)

Haghparast, H; Ghorbani, A; Rohlin, M

2017-08-01

To compare dental students' perceptions of their learning approaches between different years of a problem-based learning (PBL) programme. The hypothesis was that in a comparison between senior and junior students, the senior students would perceive themselves as having a higher level of deep learning approach and a lower level of surface learning approach than junior students would. This hypothesis was based on the fact that senior students have longer experience of a student-centred educational context, which is supposed to underpin student learning. Students of three cohorts (first year, third year and fifth year) of a PBL-based dental programme were asked to respond to a questionnaire (R-SPQ-2F) developed to analyse students' learning approaches, that is deep approach and surface approach, using four subscales including deep strategy, surface strategy, deep motive and surface motive. The results of the three cohorts were compared using a one-way analysis of variance (ANOVA). A P-value was set at approach than the first-year students (P = 0.020). There was a significant decrease in surface strategy from the first to the fifth year (P = 0.003). No differences were found concerning deep approach or its subscales (deep strategy and deep motive) between the mean scores of the three cohorts. The results did not show the expected increased depth in learning approaches over the programme years. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.