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  1. Article ; Online: Building an institutional K awardee program at UC Davis through utilization of CTSA resources.

    Guo, Betty P / Rainwater, Julie / Neves, Stacey / Anuurad, Erdembileg / Wun, Ted / Berglund, Lars

    Journal of clinical and translational science

    2021  Volume 5, Issue 1, Page(s) e171

    Abstract: NIH offers multiple mentored career development award mechanisms. By building on the UC Davis Clinical and Translational Science Center (CTSC) from its initial NIH funding in 2006, we created an institution-wide K scholar resource. We investigated ... ...

    Abstract NIH offers multiple mentored career development award mechanisms. By building on the UC Davis Clinical and Translational Science Center (CTSC) from its initial NIH funding in 2006, we created an institution-wide K scholar resource. We investigated subsequent NIH funding for K scholars and to what extent CTSC research resources were used. Using NIH RePORTER, we created a database of UC Davis investigators who obtained K01, K08, K23, K25, or K99, as well as institutional KL2 or K12 awards and tracked CTSC research resource use and subsequent funding success. Overall, 94 scholars completed K training between 2007 and 2020, of which 70 participated in one of four institutional, NIH-funded K programs. An additional 103 scholars completed a mentored clinical research training program. Of 94 K awardees, 61 (65%) later achieved NIH funding, with the majority receiving a subsequent individual K award. A higher proportion (73%) of funded scholars used CTSC resources compared to unfunded (48%). Biostatistics and Biomedical Informatics were most commonly used and 55% of scholars used one or more CTSC resource. We conclude that institutional commitment to create a K scholar platform and use of CTSC research resources is associated with high NIH funding rates for early career investigators.
    Language English
    Publishing date 2021-08-13
    Publishing country England
    Document type Journal Article
    ISSN 2059-8661
    ISSN (online) 2059-8661
    DOI 10.1017/cts.2021.839
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Infection-generated electric field in gut epithelium drives bidirectional migration of macrophages.

    Sun, Yaohui / Reid, Brian / Ferreira, Fernando / Luxardi, Guillaume / Ma, Li / Lokken, Kristen L / Zhu, Kan / Xu, Gege / Sun, Yuxin / Ryzhuk, Volodymyr / Guo, Betty P / Lebrilla, Carlito B / Maverakis, Emanual / Mogilner, Alex / Zhao, Min

    PLoS biology

    2019  Volume 17, Issue 4, Page(s) e3000044

    Abstract: Many bacterial pathogens hijack macrophages to egress from the port of entry to the lymphatic drainage and/or bloodstream, causing dissemination of life-threatening infections. However, the underlying mechanisms are not well understood. Here, we report ... ...

    Abstract Many bacterial pathogens hijack macrophages to egress from the port of entry to the lymphatic drainage and/or bloodstream, causing dissemination of life-threatening infections. However, the underlying mechanisms are not well understood. Here, we report that Salmonella infection generates directional electric fields (EFs) in the follicle-associated epithelium of mouse cecum. In vitro application of an EF, mimicking the infection-generated electric field (IGEF), induces directional migration of primary mouse macrophages to the anode, which is reversed to the cathode upon Salmonella infection. This infection-dependent directional switch is independent of the Salmonella pathogenicity island 1 (SPI-1) type III secretion system. The switch is accompanied by a reduction of sialic acids on glycosylated surface components during phagocytosis of bacteria, which is absent in macrophages challenged by microspheres. Moreover, enzymatic cleavage of terminally exposed sialic acids reduces macrophage surface negativity and severely impairs directional migration of macrophages in response to an EF. Based on these findings, we propose that macrophages are attracted to the site of infection by a combination of chemotaxis and galvanotaxis; after phagocytosis of bacteria, surface electrical properties of the macrophage change, and galvanotaxis directs the cells away from the site of infection.
    MeSH term(s) Animals ; Bacterial Proteins ; Cell Movement/physiology ; Electric Conductivity ; Electricity ; Epithelium/immunology ; Epithelium/metabolism ; Female ; Gastrointestinal Tract/immunology ; Macrophages/microbiology ; Macrophages/physiology ; Male ; Mice ; Mice, Inbred C57BL ; Phagocytosis ; Salmonella/pathogenicity ; Salmonella Infections/metabolism ; Salmonella Infections/physiopathology ; Taxis Response/physiology
    Chemical Substances Bacterial Proteins
    Language English
    Publishing date 2019-04-09
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2126776-5
    ISSN 1545-7885 ; 1544-9173
    ISSN (online) 1545-7885
    ISSN 1544-9173
    DOI 10.1371/journal.pbio.3000044
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Rapid genetic analysis of Helicobacter pylori gastric mucosal colonization in suckling mice.

    Guo, Betty P / Mekalanos, John J

    Proceedings of the National Academy of Sciences of the United States of America

    2002  Volume 99, Issue 12, Page(s) 8354–8359

    Abstract: Previously described animal models for Helicobacter pylori infection have been limited by cumbersome host requirements (e.g., germ-free conditions or unusual species) or are applicable to only special subsets of H. pylori strains (e.g., fresh clinical ... ...

    Abstract Previously described animal models for Helicobacter pylori infection have been limited by cumbersome host requirements (e.g., germ-free conditions or unusual species) or are applicable to only special subsets of H. pylori strains (e.g., fresh clinical isolates or animal-adapted derivatives). Here, we report that 5- to 6-day-old outbred CD-1 (ICR) suckling mice support 24-h colonization of all H. pylori strains tested (SS1, 26695 SmR-1, 43504 SmR-1, and G27 SmR-1), including lab-passaged strains that cannot be adapted for colonization of adult animals. Total colony-forming units (cfu) recovered from infection with lab-passaged strains did not differ from those with mouse-adapted SS1. We also tested this model's ability to detect colonization defects in strains carrying mutations in known virulence genes by coinfecting with wild-type H. pylori and measuring differential recovery. This competition assay identified colonization defects in several classes of known attenuated mutants, including those defective in acid resistance (ureA), metabolism (frdA), motility (motB), and chemotaxis (cheY). A mutant defective in copA (copper transporting P-type ATPase) is nonattenuated in adult and infant mice. Possibly because of the limited duration of infection, our model did not identify defects in vacuolating cytotoxin (vacA) or gamma-glutamyltranspeptidase (ggt) as attenuating, in contrast to results from other animal models. We also identified a new virulence gene (HP0507) encoding a conserved hypothetical protein, which is important for colonization in our model. The suckling mouse model offers a rapid method to identify colonization defects in any H. pylori strain and may have utility as a new tool for studying immunity to primary infection.
    MeSH term(s) Aging ; Amino Acid Sequence ; Animals ; Animals, Suckling ; DNA Primers ; Gastric Mucosa/microbiology ; Helicobacter pylori/growth & development ; Helicobacter pylori/isolation & purification ; Helicobacter pylori/pathogenicity ; Humans ; Mice ; Mice, Inbred ICR ; Molecular Sequence Data ; Mutagenesis ; Mutation ; Sequence Alignment ; Sequence Homology, Amino Acid
    Chemical Substances DNA Primers
    Language English
    Publishing date 2002-06-11
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.122244899
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: In situ immune response in brain and kidney during early relapsing fever borreliosis.

    Andersson, Marie / Nordstrand, Annika / Shamaei-Tousi, Alireza / Jansson, Anna / Bergström, Sven / Guo, Betty P

    Journal of neuroimmunology

    2007  Volume 183, Issue 1-2, Page(s) 26–32

    Abstract: Characterization of the host immune response during initial pathogenesis of relapsing fever neuroborreliosis would be a key to understanding Borrelia persistence and factors driving the inflammatory process. We analyzed immune cells in brain and kidney ... ...

    Abstract Characterization of the host immune response during initial pathogenesis of relapsing fever neuroborreliosis would be a key to understanding Borrelia persistence and factors driving the inflammatory process. We analyzed immune cells in brain and kidney with the highly invasive B. crocidurae during the first two weeks of murine infection. In both organs, microglia and/or macrophages predominated while T-cell changes were minimal. Compared to kidney, brain neutrophils infiltrated more rapidly and B-cells were essentially absent. Our results indicate that during early neuroborreliosis, brain defense is comprised primarily of innate immune cells while adaptive immunity plays a minor role.
    MeSH term(s) Animals ; Antigens, Differentiation/metabolism ; Borrelia Infections/complications ; Borrelia Infections/immunology ; Brain/immunology ; Immunohistochemistry/methods ; Kidney/immunology ; Macrophages/metabolism ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Neuropil/metabolism ; Relapsing Fever/etiology ; Relapsing Fever/immunology ; Spirochaetales/isolation & purification ; Time Factors
    Chemical Substances Antigens, Differentiation
    Language English
    Publishing date 2007-02
    Publishing country Netherlands
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 8335-5
    ISSN 1872-8421 ; 0165-5728
    ISSN (online) 1872-8421
    ISSN 0165-5728
    DOI 10.1016/j.jneuroim.2006.11.004
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Persistent brain infection and disease reactivation in relapsing fever borreliosis.

    Larsson, Christer / Andersson, Marie / Pelkonen, Jenni / Guo, Betty P / Nordstrand, Annika / Bergström, Sven

    Microbes and infection

    2006  Volume 8, Issue 8, Page(s) 2213–2219

    Abstract: Relapsing fever, an infection caused by Borrelia spirochetes, is generally considered a transient, self-limiting disease in humans. The present study reveals that murine infection by Borrelia duttonii can be reactivated after an extended time as a silent ...

    Abstract Relapsing fever, an infection caused by Borrelia spirochetes, is generally considered a transient, self-limiting disease in humans. The present study reveals that murine infection by Borrelia duttonii can be reactivated after an extended time as a silent infection in the brain, with no bacteria appearing in the blood and spirochete load comparable to the numbers in an infected tick. The host cerebral gene expression pattern is indistinguishable from that of uninfected animals, indicating that persistent bacteria are not recognized by the immune system nor cause noticeable tissue damage. Silent infection can be reactivated by immunosuppression, inducing spirochetemia comparable to that of initial densities. B. duttonii has never been found in any host except man and the tick vector. We therefore propose the brain to be a possible natural reservoir of the spirochete. The view of relapsing fever as an acute disease should be extended to include in some cases prolonged persistence, a feature characteristic of the related spirochetal infections Lyme disease and syphilis.
    MeSH term(s) Animals ; Bacteremia ; Borrelia/classification ; Borrelia/isolation & purification ; Brain/microbiology ; Brain Chemistry ; Brain Diseases/microbiology ; Colony Count, Microbial ; Disease Models, Animal ; Gene Expression Profiling ; Immunosuppression ; Male ; Mice ; Mice, Inbred C57BL ; Relapsing Fever/microbiology ; Serotyping
    Language English
    Publishing date 2006-07
    Publishing country France
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1465093-9
    ISSN 1769-714X ; 1286-4579
    ISSN (online) 1769-714X
    ISSN 1286-4579
    DOI 10.1016/j.micinf.2006.04.007
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Relapsing fever Borrelia binds to neolacto glycans and mediates rosetting of human erythrocytes.

    Guo, Betty P / Teneberg, Susann / Münch, Robert / Terunuma, Daiyo / Hatano, Ken / Matsuoka, Koji / Angström, Jonas / Borén, Thomas / Bergström, Sven

    Proceedings of the National Academy of Sciences of the United States of America

    2009  Volume 106, Issue 46, Page(s) 19280–19285

    Abstract: A hallmark of acute relapsing fever borreliosis is severe bacteremia. Some Borrelia species, such as B. duttonii and B. crocidurae, associate with erythrocytes and induce aggregation recognized as erythrocyte rosetting. Erythrocyte rosettes contribute to ...

    Abstract A hallmark of acute relapsing fever borreliosis is severe bacteremia. Some Borrelia species, such as B. duttonii and B. crocidurae, associate with erythrocytes and induce aggregation recognized as erythrocyte rosetting. Erythrocyte rosettes contribute to disease severity by increased tissue invasiveness (such as invasion of CNS and encephalitis), hemorrhaging, and reduced blood flow in affected microcapillaries. Here we report that relapsing fever Borrelia binds to neolacto (Galbeta4GlcNAcbeta3Galbeta4Glcbeta1)-carrying glycoconjugates that are present on human erythrocytes. This interaction is of low affinity but is compensated for by the multivalency of neo-lacto-oligosaccharides on the erythrocyte cell surface. Hence, the protein-carbohydrate interaction is dependent on multivalent neolacto-glycans to mediate binding.
    MeSH term(s) Borrelia/immunology ; Epitopes/immunology ; Erythrocytes/immunology ; Erythrocytes/microbiology ; Globosides/immunology ; Humans ; Polysaccharides/immunology ; Relapsing Fever/immunology ; Relapsing Fever/microbiology ; Rosette Formation/methods
    Chemical Substances Epitopes ; Globosides ; Polysaccharides ; paragloboside (56573-54-7)
    Language English
    Publishing date 2009-11-02
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.0905470106
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Molecular cloning and characterization of two Helicobacter pylori genes coding for plasminogen-binding proteins.

    Jönsson, Klas / Guo, Betty P / Monstein, Hans-Jürg / Mekalanos, John J / Kronvall, Göran

    Proceedings of the National Academy of Sciences of the United States of America

    2004  Volume 101, Issue 7, Page(s) 1852–1857

    Abstract: Helicobacter pylori binds a number of host cell proteins, including the plasma protein plasminogen, which is the proenzyme of the serine protease plasmin. Two H. pylori plasminogen-binding proteins have been described; however, no genes were identified. ... ...

    Abstract Helicobacter pylori binds a number of host cell proteins, including the plasma protein plasminogen, which is the proenzyme of the serine protease plasmin. Two H. pylori plasminogen-binding proteins have been described; however, no genes were identified. Here we report the use of a phage display library to clone two genes from the H. pylori CCUG 17874 genome that mediate binding to plasminogen. DNA sequence analysis of one of these genes revealed 96.6% homology with H. pylori 26695 HP0508. A subsequent database search revealed that the amino acid sequence of a lysine-rich C-terminal segment of HP0508 is identical to the C terminus of HP0863. Recombinant proteins expressed from HP0508 and HP0863 bound plasminogen specifically and in a lysine-dependent manner. We designate these genes pgbA and pgbB, respectively. These proteins are expressed by a variety of H. pylori strains, have surface-exposed domains, and do not inhibit plasminogen activation. These results indicate that pgbA and pgbB may allow H. pylori to coat its exterior with plasminogen, which subsequently can be activated to plasmin. The surface acquisition of protease activity may enhance the virulence of H. pylori.
    MeSH term(s) Amino Acid Sequence ; Bacterial Proteins/chemistry ; Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; Carrier Proteins/chemistry ; Carrier Proteins/genetics ; Carrier Proteins/metabolism ; Cloning, Molecular ; Computational Biology ; Fibrinolysin/metabolism ; Genes, Bacterial/genetics ; Helicobacter pylori/genetics ; Lysine/metabolism ; Molecular Sequence Data ; Plasminogen/metabolism ; Protein Binding ; Recombinant Proteins/chemistry ; Recombinant Proteins/genetics ; Recombinant Proteins/metabolism
    Chemical Substances Bacterial Proteins ; Carrier Proteins ; Recombinant Proteins ; plasminogen-binding protein, bacteria ; Plasminogen (9001-91-6) ; Fibrinolysin (EC 3.4.21.7) ; Lysine (K3Z4F929H6)
    Language English
    Publishing date 2004-02-09
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.0307329101
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Complications of pregnancy and transplacental transmission of relapsing-fever borreliosis.

    Larsson, Christer / Andersson, Marie / Guo, Betty P / Nordstrand, Annika / Hagerstrand, Inga / Carlsson, Sara / Bergstrom, Sven

    The Journal of infectious diseases

    2006  Volume 194, Issue 10, Page(s) 1367–1374

    Abstract: Relapsing-fever borreliosis caused by Borrelia duttonii is a common cause of complications of pregnancy, miscarriage, and neonatal death in sub-Saharan Africa. We established a murine model of gestational relapsing fever infection for the study of the ... ...

    Abstract Relapsing-fever borreliosis caused by Borrelia duttonii is a common cause of complications of pregnancy, miscarriage, and neonatal death in sub-Saharan Africa. We established a murine model of gestational relapsing fever infection for the study of the pathological development of these complications. We demonstrate that B. duttonii infection during pregnancy results in intrauterine growth retardation, as well as placental damage and inflammation, impaired fetal circulation, and decreased maternal hemoglobin levels. We show that spirochetes frequently cross the maternal-fetal barrier, resulting in congenital infection. Furthermore, we compared the severity of infection in pregnant and nonpregnant mice and show that pregnancy has a protective effect. This model closely parallels the consequences of human gestational infection, and our results provide insight into the mechanisms behind the complications of pregnancy that have been reported in human relapsing-fever infection.
    MeSH term(s) Animals ; Bacteremia ; Borrelia ; Disease Models, Animal ; Female ; Fetal Diseases/microbiology ; Fetal Diseases/pathology ; Fetal Growth Retardation ; Fetal Weight ; Hemoglobins/analysis ; Histocytochemistry ; Infectious Disease Transmission, Vertical ; Mice ; Mice, Inbred C3H ; Placenta/microbiology ; Placenta/pathology ; Placental Circulation ; Pregnancy ; Pregnancy Complications, Infectious/microbiology ; Pregnancy Complications, Infectious/pathology ; Relapsing Fever/microbiology ; Relapsing Fever/pathology ; Relapsing Fever/transmission
    Chemical Substances Hemoglobins
    Language English
    Publishing date 2006-11-15
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 3019-3
    ISSN 1537-6613 ; 0022-1899
    ISSN (online) 1537-6613
    ISSN 0022-1899
    DOI 10.1086/508425
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Relapsing fever Borrelia binds to neolacto glycans and mediates rosetting of human erythrocytes

    Guo, Betty P / Teneberg, Susann / Münch, Robert / Terunuma, Daiyo / Hatano, Ken / Matsuoka, Koji / Ångström, Jonas / Borén, Thomas / Bergström, Sven

    Proceedings of the National Academy of Sciences of the United States of America. 2009 Nov. 17, v. 106, no. 46

    2009  

    Abstract: A hallmark of acute relapsing fever borreliosis is severe bacteremia. Some Borrelia species, such as B. duttonii and B. crocidurae, associate with erythrocytes and induce aggregation recognized as erythrocyte rosetting. Erythrocyte rosettes contribute to ...

    Abstract A hallmark of acute relapsing fever borreliosis is severe bacteremia. Some Borrelia species, such as B. duttonii and B. crocidurae, associate with erythrocytes and induce aggregation recognized as erythrocyte rosetting. Erythrocyte rosettes contribute to disease severity by increased tissue invasiveness (such as invasion of CNS and encephalitis), hemorrhaging, and reduced blood flow in affected microcapillaries. Here we report that relapsing fever Borrelia binds to neolacto (Galβ4GlcNAcβ3Galβ4Glcβ1)-carrying glycoconjugates that are present on human erythrocytes. This interaction is of low affinity but is compensated for by the multivalency of neo-lacto-oligosaccharides on the erythrocyte cell surface. Hence, the protein-carbohydrate interaction is dependent on multivalent neolacto-glycans to mediate binding.
    Keywords Borrelia ; Lyme disease ; bacteremia ; blood flow ; disease severity ; encephalitis ; erythrocytes ; fever ; glycoconjugates ; humans ; polysaccharides
    Language English
    Dates of publication 2009-1117
    Size p. 19280-19285.
    Publishing place National Academy of Sciences
    Document type Article
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.0905470106
    Database NAL-Catalogue (AGRICOLA)

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