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Expression Of Toxoplasma Gondii-Specific Heat Shock Protein 70 During In Vivo Conversion Of Bradyzoites To Tachyzoites, Neide M. Silva, Ricardo T. Gazzinelli, Deise A. O. Silva, Eloisa A. V. Ferro, Lloyd H. Kasper, Jose R. Mineo Aug 1998

Expression Of Toxoplasma Gondii-Specific Heat Shock Protein 70 During In Vivo Conversion Of Bradyzoites To Tachyzoites, Neide M. Silva, Ricardo T. Gazzinelli, Deise A. O. Silva, Eloisa A. V. Ferro, Lloyd H. Kasper, Jose R. Mineo

Dartmouth Scholarship

Stage conversion between bradyzoites and tachyzoites was investigated in C57BL/6 mice chronically infected with the ME-49 strain of Toxoplasma gondii. In order to promote bradyzoite-tachyzoite conversion, mice were treated in vivo with neutralizing doses of anti-gamma interferon (IFN-gamma) or anti-tumor necrosis factor alpha (TNF-alpha) antibodies. Expression of parasite-specific antigens SAG-1, SAG-2, and heat shock protein 70 (Hsp-70) was visualized in the central nervous system by immunocytochemistry and measured by photometric assay. The immunosuppressive effect of anti-IFN-gamma or anti-TNF-alpha treatment was immediate, leading to parasite stage conversion as indicated by the increased expression of tachyzoite-specific antigens (SAG-1 and SAG-2) and by …

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Evaluation Of The Success Of Adoptive Versus Passive Transfer Of Immunity Against Trypanosoma Cruzi, Karen Powell May 1998

Evaluation Of The Success Of Adoptive Versus Passive Transfer Of Immunity Against Trypanosoma Cruzi, Karen Powell

Masters Theses & Specialist Projects

Several investigators have demonstrated an increased resistance to the protozoal parasite Trypanosoma cruzi (the causative agent of Chagas' disease) in highly susceptible C3H mice when maintained at an environmental temperature of 36°C. This increased resistance is manifested as delay in onset of parasitemia, decreased parasitemia, decreased pathology, and increased longevity with eventual clearing of the parasite from the bloodstream. In addition, this enhanced resistance has been shown to be an immunologic phenomenon and not due to the direct effects of elevated temperature on the parasite itself. To ascertain the possible contributions of humoral vs. cellular immunity to the above phenomenon, …

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Antigen-Specific Cd8+ T Cells Protect Against Lethal Toxoplasmosis In Mice Infected With Neospora Caninum, Lloyd H. Kasper, Imtiaz A. Khan Apr 1998

Antigen-Specific Cd8+ T Cells Protect Against Lethal Toxoplasmosis In Mice Infected With Neospora Caninum, Lloyd H. Kasper, Imtiaz A. Khan

Dartmouth Scholarship

Neospora caninum is a coccidial protozoan parasite that appears morphologically indistinguishable from Toxoplasma gondii and that infects a large range of mammals. Both inbred and outbred strains of mice exhibit a high degree of resistance to infection with N. caninum. Three inbred strains of mice (A/J, BALB/c, and C57BL/6) that were infected intraperitoneally with N. caninum were protected against a lethal challenge from T. gondii. Vaccine-induced protection was Neospora dose dependent. A rise in the CD8+ T-cell population in mice that had been vaccinated with N. caninum and challenged with T. gondii was observed. Adoptive transfer of CD8+ T-cell splenocytes …

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Enhancement Of Atp Levels And Glucose Metabolism During An Infection By Chlamydia: Nmr Studies Of Living Cells, David M. Ojcius, H. Degani, Joel Mispelter, Alice Dautry-Varsat Mar 1998

Enhancement Of Atp Levels And Glucose Metabolism During An Infection By Chlamydia: Nmr Studies Of Living Cells, David M. Ojcius, H. Degani, Joel Mispelter, Alice Dautry-Varsat

All Dugoni School of Dentistry Faculty Articles

The Chlamydia species are obligate intracellular bacteria that proliferate only within the infected cell. Since the extracellular bacteria are metabolically inert and there are no cell-free systems for characterizingChlamydia metabolism, we studied metabolic changes related to ATP synthesis and glycolysis in HeLa cells infected withChlamydia psittaci during the course of the 2-day infection cycle using noninvasive 31P and 13C NMR methods. We find that the infection stimulates ATP synthesis in the infected cell, with a peak of ATP levels occurring midway through the infection cycle, when most of the metabolically active bacteria are proliferating. The infection also stimulates synthesis of …

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Chlamydia Trachomatis Infection In The Female Reproductive Tract Of The Rat: Influence Of Progesterone On Infectivity And Immune Response, Charu Kaushic, Andrew D. Murdin, Brian J. Underdown, Charles R. Wira Mar 1998

Chlamydia Trachomatis Infection In The Female Reproductive Tract Of The Rat: Influence Of Progesterone On Infectivity And Immune Response, Charu Kaushic, Andrew D. Murdin, Brian J. Underdown, Charles R. Wira

Dartmouth Scholarship

As the most common cause of sexually transmitted disease in women, chlamydial infections can lead to pelvic inflammatory disease, infertility, and ectopic pregnancy. To better understand the role played by sex hormones in modulating the immune response of the genital tract to microbial infections, we have developed a rat model to study Chlamydia trachomatis infection. Inbred female Lewis rats were primed with progesterone and inoculated by intrauterine instillation of C. trachomatis (mouse pneumonitis strain MoPn) into each uterine horn. When infected animals were examined for the presence of chlamydial antigens 14 days postinfection, both the uterus and vagina were found …

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Investigation Of The Roles Of Toxin-Coregulated Pili And Mannose-Sensitive Hemagglutinin Pili In The Pathogenesis Of Vibrio Cholerae O139 Infection, Carol O. Tacket, Ronald K. Taylor, Genevieve Losonsky, Yu Lim Feb 1998

Investigation Of The Roles Of Toxin-Coregulated Pili And Mannose-Sensitive Hemagglutinin Pili In The Pathogenesis Of Vibrio Cholerae O139 Infection, Carol O. Tacket, Ronald K. Taylor, Genevieve Losonsky, Yu Lim

Dartmouth Scholarship

In this study, adult volunteers were fed tcpA and mshA deletion mutants of V. cholerae O139 strain CVD 112 to determine the role of toxin-coregulated pili (TCP) and mannose-sensitive hemagglutinin (MSHA) in intestinal colonization. Eight of 10 volunteers who received CVD 112 or CVD 112 ΔmshA shed the vaccine strains in their stools; the geometric mean peak excretion for both groups was 1.4 × 105 CFU/g of stool. In contrast, only one of nine recipients of CVD 112 ΔtcpA shed vibrios in his stool (P < 0.01); during the first 24 h after inoculation, 3 × 102 CFU/g was recovered from this volunteer. All recipients of CVD …

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Gp120 Envelope Glycoproteins Of Human Immunodeficiency Viruses Competitively Antagonize Signaling By Coreceptors Cxcr4 And Ccr5, Navid Madani, Susan L. Kozak, Michael Kavanaugh, David Kabat Jan 1998

Gp120 Envelope Glycoproteins Of Human Immunodeficiency Viruses Competitively Antagonize Signaling By Coreceptors Cxcr4 And Ccr5, Navid Madani, Susan L. Kozak, Michael Kavanaugh, David Kabat

Biomedical and Pharmaceutical Sciences Faculty Publications

Signal transductions by the dual-function CXCR4 and CCR5 chemokine receptors/HIV type 1 (HIV-1) coreceptors were electrophysiologically monitored in Xenopus laevis oocytes that also coexpressed the viral receptor CD4 and a G protein-coupled inward-rectifying K+ channel (Kir 3.1). Large Kir 3.1-dependent currents generated in response to the corresponding chemokines (SDF-1α for CXCR4 and MIP-1α; MIP-1β and RANTES for CCR5) were blocked by pertussis toxin, suggesting involvement of inhibitory guanine nucleotide-binding proteins. Prolonged exposures to chemokines caused substantial but incomplete desensitization of responses with time constants of 5–7 min and recovery time constants of 12–19 min. CXCR4 and CCR5 exhibited heterologous …

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Health Professions Division Catalog Academic Year 1998-1999, Nova Southeastern University Jan 1998

Health Professions Division Catalog Academic Year 1998-1999, Nova Southeastern University

Health Professions Divisions Course Catalogs and Course Descriptions

No abstract provided.

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Cyclospora Sp. Associated With Diarrhea In Apatient With Aids In Turkey, A. Nedret Koç, Bilge Aygen, İzzet Şahi̇n, Üner Kayabaş Jan 1998

Cyclospora Sp. Associated With Diarrhea In Apatient With Aids In Turkey, A. Nedret Koç, Bilge Aygen, İzzet Şahi̇n, Üner Kayabaş

Turkish Journal of Medical Sciences

No abstract provided.

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Detection Of Antinuclear Antibody (Ana) Inpatients With Mycoplasmal Pneumonia, Sevtap Arikan, Sibel Ergüven, Şemsettin Ustaçelebi̇ Jan 1998

Detection Of Antinuclear Antibody (Ana) Inpatients With Mycoplasmal Pneumonia, Sevtap Arikan, Sibel Ergüven, Şemsettin Ustaçelebi̇

Turkish Journal of Medical Sciences

No abstract provided.

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Polyadenylation Of Vesicular Stomatitis Virus Mrna Dictates Efficient Transcription Termination At The Intercistronic Gene Junctions, Leroy N. Hwang, Nathan Englund, Asit K. Pattnaik Jan 1998

Polyadenylation Of Vesicular Stomatitis Virus Mrna Dictates Efficient Transcription Termination At The Intercistronic Gene Junctions, Leroy N. Hwang, Nathan Englund, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

The intercistronic gene junctions of vesicular stomatitis virus (VSV) contain conserved sequence elements that are important for polyadenylation and transcription termination of upstream transcript as well as reinitiation of transcription of downstream transcript. To examine the role of the putative polyadenylation signal 3' AUACU75' at the gene junctions in polyadenylation and transcription termination, we constructed plasmids encoding antigenomic minireplicons containing one or two transcription units. In plasmid-transfected cells, analyses of the bicistronic minireplicon containing the wild-type or mutant intercistronic gene junctions for the ability to direct synthesis of polyadenylated upstream, downstream, and readthrough mRNAs showed that the AUACU …

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A Dichotomous Role For Nitric Oxide During Acute Toxoplasma Gondii Infection In Mice, Imtiaz A. Khan, Joseph D. Schwartzman, Tadashi Matsuura, Lloyd H. Kasper Dec 1997

A Dichotomous Role For Nitric Oxide During Acute Toxoplasma Gondii Infection In Mice, Imtiaz A. Khan, Joseph D. Schwartzman, Tadashi Matsuura, Lloyd H. Kasper

Dartmouth Scholarship

Production of nitric oxide by macrophages is believed to be an important microbicidal mechanism for a variety of intracellular pathogens, including Toxoplasma gondii. Mice with a targeted disruption of the inducible nitric oxide synthase gene (iNOS) were infected orally with T. gondii tissue cysts. Time to death was prolonged compared with parental controls. Histologic analysis of tissue from infected mice showed scattered small foci of inflammation with parasites in various tissues of iNOS−/− mice, whereas tissue from the parental C57BL/6 mice had more extensive tissue inflammation with few visible parasites. In particular, extensive ulceration and necrosis of distal small …

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The Beneficial Effect Of Vitamin E And Selenium During Experimental Chagas' Disease, Yue Hou Aug 1997

The Beneficial Effect Of Vitamin E And Selenium During Experimental Chagas' Disease, Yue Hou

Masters Theses & Specialist Projects

The present study was conducted to determine if vitamin E and selenium could have a positive synergistic effect during experimental Chagas' disease. In the first phase of the study, 25 female C3HeB/FeJ mice were infected with a Brazil strain of Trypanosoma cruzi while receiving vitamin E supplementation of 0 IU/kg, 200 IU/kg, 400 IU/kg, 600 IU/kg, 800 IU/kg in their diets. In the second phase, 20 female C3HeB/FeJ mice were infected while receiving 400 IU/kg vitamin E plus selenium supplementation of 2 ppm, 4 ppm, 8 ppm, 16 ppm in their drinking water. The results demonstrate that vitamin E does …

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Distribution Of Endosomal, Lysosomal And Mhc Markers In A Monocytic Cell Line Infected With Chlamydia Psittaci, David M. Ojcius, Raymond Hellio, Alice Dautry-Varsat Jun 1997

Distribution Of Endosomal, Lysosomal And Mhc Markers In A Monocytic Cell Line Infected With Chlamydia Psittaci, David M. Ojcius, Raymond Hellio, Alice Dautry-Varsat

All Dugoni School of Dentistry Faculty Articles

The intracellular fate of Chlamydia psittaci during infection of a monocytic cell line, THP1, was characterized. Cytochalasin D inhibited phagocytosis of latex beads but had no effect on infection by C. psittaci, and vacuoles expressed the transferrin receptor, suggesting accessibility to the endocytic pathway. Early Chlamydia-containing vacuoles expressed major histocompatibility complex (MHC) class I molecules, and most vacuoles fused with host cell lysosomes, since they expressed LAMP-1 and had acidic pHs. In cells prestimulated with gamma interferon, vacuoles also expressed MHC class II molecules, suggesting that the monocytes might effectively process Chlamydia-derived antigens for presentation by MHC class I and …

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Phosphorylation Within The Amino-Terminal Acidic Domain I Of The Phosphoprotein Of Vesicular Stomatitis Virus Is Required For Transcription But Not For Replication, Asit K. Pattnaik, Leroy Hwang, Tong Le, Nathan Englund, Manjula Mathur, Tapas Das, Amiya Banerjee Jan 1997

Phosphorylation Within The Amino-Terminal Acidic Domain I Of The Phosphoprotein Of Vesicular Stomatitis Virus Is Required For Transcription But Not For Replication, Asit K. Pattnaik, Leroy Hwang, Tong Le, Nathan Englund, Manjula Mathur, Tapas Das, Amiya Banerjee

School of Veterinary and Biomedical Sciences: Faculty Publications

Phosphorylation by casein kinase II at three specific residues (S-60, T-62, and S-64) within the acidic domain I of the P protein of Indiana serotype vesicular stomatitis virus has been shown to be critical for in vitro transcription activity of the viral RNA polymerase (P-L) complex. To examine the role of phosphorylation of P protein in transcription as well as replication in vivo, we used a panel of mutant P proteins in which the phosphate acceptor sites in domain I were substituted with alanines or other amino acids. Analyses of the alanine-substituted mutant P proteins for the ability to support …

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Cellular Basis Of Decreased Immune Responses To Pneumococcal Vaccines In Aged Mice, Manju Garg, Wei Luo, Alan M. Kaplan, Subbarao Bondada Nov 1996

Cellular Basis Of Decreased Immune Responses To Pneumococcal Vaccines In Aged Mice, Manju Garg, Wei Luo, Alan M. Kaplan, Subbarao Bondada

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Previously, model systems were developed in our laboratory to study murine immune responses to the 23-valent pneumococcal polysaccharide vaccine Pnu-Imune, both in vivo and in vitro (M. Garg and B. Subbarao, Infect. Immun. 60:2329-2336, 1992; M. Garg, A. M. Kaplan, and S. Bondada, J. Immunol. 152: 1589-1596, 1994). Using these systems, we found that aged mice did not respond to the vaccine in vivo or in vitro. Cell separation studies showed that the unresponsiveness of the aged spleen cells to the vaccine was not due to an intrinsic B-cell defect or to T-cell-mediated immunosuppression but resulted from an accessory cell …

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Attachment Of Toxoplasma Gondii To Host Cells Is Host Cell Cycle Dependent., Jane Grimwood, Jose R. Mineo, Lloyd H. Kasper Oct 1996

Attachment Of Toxoplasma Gondii To Host Cells Is Host Cell Cycle Dependent., Jane Grimwood, Jose R. Mineo, Lloyd H. Kasper

Dartmouth Scholarship

The initial attachment of Toxoplasma tachyzoites to target host cells is an important event in the life cycle of the parasite and hence critical in the pathogenesis of this infection. The efficiency of Toxoplasma attachment to synchronized populations of Chinese hamster ovary cells and bovine kidney cells was investigated by using a glutaraldehyde-fixed host cell assay system. For both cell lines, parasite attachment increased as the synchronized host cells proceeded from the G1 phase to the mid-S phase and then decreased as the cells entered the G2-M boundary. Postulating that these differences in attachment reflect the upregulation of a specific …

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The Effects Of Lead Acetate On Host Susceptibility To Trypanosoma Cruzi, Tabitha Ellis Aug 1996

The Effects Of Lead Acetate On Host Susceptibility To Trypanosoma Cruzi, Tabitha Ellis

Masters Theses & Specialist Projects

Trypanosoma cruzi. a protozoan parasite, causes American trypanosomiasis or Chagas' disease. The infective stage of this parasite resides in the hindgut of the reduviid bug (family Reduviidae), which is both host and vector, and is transmitted to the mammalian host through fecal material released during a blood meal. Chagas' disease, an acute to chronic infection resulting in fever, malaise, and heart and liver enlargement, is becoming a concern in the United States due to the large increase in Latin American immigrants, and the lack of safe and effective therapeutic treatment and vaccination. Another growing concern in the United States involves …

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Interleukin-10 Inhibits Tumor Metastasis Through An Nk-Cell Dependent Mechanism, Li-Mou Zheng, David M. Ojcius, F. Garaud, C. Roth, E. Maxwell, Z. Li, H. Rong, J. Chen, X. Y. Wang, J. J. Catino, I. King Aug 1996

Interleukin-10 Inhibits Tumor Metastasis Through An Nk-Cell Dependent Mechanism, Li-Mou Zheng, David M. Ojcius, F. Garaud, C. Roth, E. Maxwell, Z. Li, H. Rong, J. Chen, X. Y. Wang, J. J. Catino, I. King

All Dugoni School of Dentistry Faculty Articles

Interleukin-10 (IL-10) is a recently described pleiotropic cytokine secreted mainly by type 2 helper T cells. Previous studies have shown that IL-10 suppresses cytokine expression by natural killer (NK) and type 1 T cells, thus down-regulating cell-mediated immunity and stimulating humoral responses. We here report that injected IL-10 protein is an efficient inhibitor of tumor metastasis in experimental (B16-F10) and spontaneous (M27 and Lox human melanoma) metastasis models in vivo at doses that do not have toxic effects on normal or cancer cells. Histological characterization after IL-10 treatment confirmed the absence of CD8+ and CD4+ T cells and macrophages at …

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Toxin-Coregulated Pilus, But Not Mannose-Sensitive Hemagglutinin, Is Required For Colonization By Vibrio Cholerae O1 El Tor Biotype And O139 Strains., K Helene Thelin, Ronald K. Taylor Jul 1996

Toxin-Coregulated Pilus, But Not Mannose-Sensitive Hemagglutinin, Is Required For Colonization By Vibrio Cholerae O1 El Tor Biotype And O139 Strains., K Helene Thelin, Ronald K. Taylor

Dartmouth Scholarship

The relative contributions of toxin-coregulated pilus (TCP) and cell-associated mannose-sensitive hemagglutinin (MSHA) to the colonization ability of Vibrio cholerae O1 El Tor biotype strains and O139 Bengal strains was determined by using isogenic parental and in-frame deletion mutant pairs in the infant mouse cholera model. Both the El Tor and O139 tcpA mutant strains showed a dramatic defect in colonization as indicated by their competitive indices, whereas deletion of mshA had a negligible effect on colonization in either background.

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Toxoplasma Gondii-Induced Immune Suppression By Human Peripheral Blood Monocytes: Role Of Gamma Interferon., Jacqueline Y. Channon, Lloyd H. Kasper Apr 1996

Toxoplasma Gondii-Induced Immune Suppression By Human Peripheral Blood Monocytes: Role Of Gamma Interferon., Jacqueline Y. Channon, Lloyd H. Kasper

Dartmouth Scholarship

The ability of Toxoplasma gondii to evade the host immune response during primary infection in humans is poorly understood. In murine toxoplasmosis, infected spleen macrophages release soluble factors that mediate a transient immunosuppression, which may allow the parasite to become established. When an enriched population of human monocytes from seronegative individuals was incubated with toxoplasmas in vitro, soluble factors that mediated market suppression of mitogen-induced lymphocyte DNA synthesis were released. Irradiated tachyzoites that do not undergo replication were sufficient stimuli for near-maximal soluble factor release. Up to 50% of the soluble factor-mediated suppression is attributable to a gamma interferon (IFN-gamma)-dependent …

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Cd40-Cd40 Ligand Interactions In Experimental Allergic Encephalomyelitis And Multiple Sclerosis., Koen Gerritse, Jon D. Laman, Randolph J. Noelle, Alejandro Aruffo Mar 1996

Cd40-Cd40 Ligand Interactions In Experimental Allergic Encephalomyelitis And Multiple Sclerosis., Koen Gerritse, Jon D. Laman, Randolph J. Noelle, Alejandro Aruffo

Dartmouth Scholarship

We investigated the role of CD40-CD40 ligand (CD40L) interactions in multiple sclerosis (MS) and experimental allergic encephalomyelitis (EAE). Activated helper T cells expressing CD40L (gp39) surface protein were found in MS patient brain sections, but not in brain tissue sections of normal controls or patients with other neurological disease. CD40L-positive cells were co-localized with CD40-bearing cells in active lesions (perivascular infiltrates). Most of these CD40-bearing cells proved to be of the monocytic lineage (macrophages or microglial cells), and relatively few were B cells. To functionally evaluate CD40-CD40L interactions, EAE was elicited in mice by means of proteolipid-peptide immunization. Treatment with …

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Health Professions Division Academic Year 1996-1997, Nova Southeastern University Jan 1996

Health Professions Division Academic Year 1996-1997, Nova Southeastern University

Health Professions Divisions Course Catalogs and Course Descriptions

No abstract provided.

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Faculty Publications 1995, Lsu Health Sciences Center New Orleans Jan 1996

Faculty Publications 1995, Lsu Health Sciences Center New Orleans

Historical Faculty Publications

This Faculty bibliography contains 703 publications.

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Bovine Cell Line Resistant To In Vtro Infection By Bovine Viral Darrheavirus And All Other Known Pestiviruses, Ruben O. Donis, Eduardo F. Flores Jan 1996

Bovine Cell Line Resistant To In Vtro Infection By Bovine Viral Darrheavirus And All Other Known Pestiviruses, Ruben O. Donis, Eduardo F. Flores

School of Veterinary and Biomedical Sciences: Faculty Publications

Bovine cell line resistant to infection by the pestiviruses Bovine Viral Diarrhea Virus (BVDV), Hog Cholera Virus (HCV) and Border Disease Virus (BDV) and all progeny and mutants thereof. A bovine cell line (CRIB) that is resistant to infection by cytopathic and non-cytopathic BVDV and by other Pestiviruses due to a stable, recessive genetic defect which blocks infection at the level of viral entry.

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Microevolutionary Patterns And Molecular Markers: The Genetics Of Geographic Variation In Ascaris Suum, Steven A. Nadler Jan 1996

Microevolutionary Patterns And Molecular Markers: The Genetics Of Geographic Variation In Ascaris Suum, Steven A. Nadler

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Molecular markers have been used only rarely to characterize the population genetic structure of nematodes. Published studies have suggested that different taxa may show distinct genetic architectures. Isoenzyme and RAPD markers have been used to investigate geographic variation of Ascaris suum at the level of infrapopulations (nematodes within individual hosts), within localities, and among geographic regions. Independent estimates of genetic differentiation among population samples based on isoenzyme and RAPD data showed similar patterns and substantial correlation. Heterozygote deficiencies within infrapopulations and large values for inbreeding coefficients among infrapopulations suggested that the composition of these populations was not consistent with a …

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Survival Of Immunoglobulin G-Opsonized Toxoplasma Gondii In Nonadherent Human Monocytes., Camilo E. Fadul, Jacqueline Y. Channon, Lloyd H. Kasper Nov 1995

Survival Of Immunoglobulin G-Opsonized Toxoplasma Gondii In Nonadherent Human Monocytes., Camilo E. Fadul, Jacqueline Y. Channon, Lloyd H. Kasper

Dartmouth Scholarship

Toxoplasma gondii is a protozoan parasite that is able to penetrate human monocytes by either passive uptake during phagocytosis or active penetration. It is expected that immunoglobulin G (IgG) opsonization will target the parasite to macrophage Fc gamma receptors for phagocytic processing and subsequent degradation. Antibody-opsonized T. gondii tachyzoites were used to infect nonadherent and adherent human monocytes obtained from the peripheral blood of seronegative individuals. The infected monocytes were evaluated for the presence of intracellular parasites and the degree of parasiticidal activity. A marked difference in both the numbers of infected macrophages and numbers of parasites per 100 macrophages …

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Ph And Calcium Dependence Of Hemolysis Due To Rickettsia Prowazekii: Comparison With Phospholipase Activity, David M. Ojcius, M. Thibon, C. Mounier, Alice Dautry-Varsat Aug 1995

Ph And Calcium Dependence Of Hemolysis Due To Rickettsia Prowazekii: Comparison With Phospholipase Activity, David M. Ojcius, M. Thibon, C. Mounier, Alice Dautry-Varsat

All Dugoni School of Dentistry Faculty Articles

Rickettsia prowazekii invades nucleated cells through phagocytosis and subsequently proliferates in the cytoplasm of the host cell. Hemolysis and a phospholipase A2 (PLA2) activity at neutral pHs have previously been reported; even though the phagosomal environment is most likely acidic. We here show that R. prowazekii and R. typhi also lyse erythrocytes at mildly acidic pHs, compatible with an early phagosomal compartment. For R. prowazekii, hemolysis at an acidic pH but not a neutral pH is enhanced by Ca2+, raising the possibility that more than one membranolytic factor may be produced by the rickettsiae. The rickettsiae alone display PLA2 activity, …

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Heterozygosity Mapping Of Partially Congenic Lines: Mapping Of A Semidominant Neurological Mutation, Wheels ( Whl), On Mouse Chromosome 4, Patrick M. Nolan, Patricia J. Sollars, Barbara A. Bohne, Warren J. Ewens, Gary E. Pickard, Maja Bucan May 1995

Heterozygosity Mapping Of Partially Congenic Lines: Mapping Of A Semidominant Neurological Mutation, Wheels ( Whl), On Mouse Chromosome 4, Patrick M. Nolan, Patricia J. Sollars, Barbara A. Bohne, Warren J. Ewens, Gary E. Pickard, Maja Bucan

School of Veterinary and Biomedical Sciences: Faculty Publications

We identified a semidominant, chemically induced, mouse use mutation with a complex array of abnormal behaviors including bidirectional circling and hyperactivity, abnormal circadian rhythmicity and abnormal responses to light. In this report, we genetically and phenotypically characterized the circling/ waltzing component of the abnormal behavior. We mapped the locus controlling this trait by heterozygosity mapping of partially congenic lines carrying the mutagenized chromosome outcrossed to different inbred strains for three generations. Analysis of 68 PCR-based markers in 13 affected individuals indicated that the mutant locus, named Wheels (Whl), resides in the subcentromeric portion of mouse chromosome 4. The …

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Polyclonal Mycobacterium Avium Infections In Patients With Aids: Variations In Antimicrobial Susceptibilities Of Different Strains Of M. Avium Isolated From The Same Patient., C Fordham Von Reyn, Nicholas J. Jacobs, Robert D. Arbeit, Joe N. Maslow, S Niemczyk Apr 1995

Polyclonal Mycobacterium Avium Infections In Patients With Aids: Variations In Antimicrobial Susceptibilities Of Different Strains Of M. Avium Isolated From The Same Patient., C Fordham Von Reyn, Nicholas J. Jacobs, Robert D. Arbeit, Joe N. Maslow, S Niemczyk

Dartmouth Scholarship

Broth microdilution MICs were determined for pairs of strains isolated from five AIDS patients with polyclonal Mycobacterium avium infection. Four (80%) of the five patients were infected simultaneously with strains having different antimicrobial susceptibility patterns. These findings have implications for the interpretation of susceptibility data in M. avium prophylaxis and treatment trials.

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