2,625 research outputs found

    ATG16L1 and pathogenesis of urinary tract infections

    Get PDF
    Autophagy is generally considered to be antipathogenic. The autophagy gene ATG16L1 has a commonly occurring mutation associated with Crohn disease (CD) and intestinal cell abnormalities. Mice hypomorphic for ATG16L1 (ATG16L1(HM)) recreate specific features of CD. Our recent study shows that the same ATG16L1(HM) mice that are susceptible to intestinal inflammatory disease are protected from urinary tract infections (UTI), a common and important human disease primarily caused by uropathogenic E. coli (UPEC). UPEC colonize the bladder and exhibit both luminal and intra-epithelial stages. The host responds by recruiting innate immune cells and shedding infected epithelial cells to clear infection. Despite these countermeasures, UPEC can persist within the bladder epithelium as membrane-enclosed quiescent intracellular reservoirs (QIRs) that can seed recurrent UTI. The mechanisms of persistence remain unknown. In this study, we show that ATG16L1 deficiency protects the host against acute UTI and UPEC latency. ATG16L1(HM) mice clear urinary bacterial loads more rapidly and thoroughly due to ATG16L1-deficient innate immune components. Furthermore, ATG16L1(HM) mice exhibit superficial urothelial cell-autonomous architectural aberrations that also result in significantly reduced QIR numbers. Our findings reveal a host-protective effect of ATG16L1 deficiency in vivo against a common pathogen

    Construction of recombinant attenuated Salmonella enterica serovar typhimurium vaccine vector strains for safety in newborn and infant mice

    Get PDF
    Recombinant bacterial vaccines must be safe, efficacious, and well tolerated, especially when administered to newborns and infants to prevent diseases of early childhood. Many means of attenuation have been shown to render vaccine strains susceptible to host defenses or unable to colonize lymphoid tissue effectively, thus decreasing their immunogenicity. We have constructed recombinant attenuated Salmonella vaccine strains that display high levels of attenuation while retaining the ability to induce high levels of immunogenicity and are well tolerated in high doses when administered to infant mice as young as 24 h old. The strains contain three means of regulated delayed attenuation, as well as a constellation of additional mutations that aid in enhancing safety, regulate antigen expression, and reduce disease symptoms commonly associated with Salmonella infection. The vaccine strains are well tolerated when orally administered to infant mice 24 h old at doses as high as 3.5 × 10(8) CFU

    Estrogenic modulation of uropathogenic Escherichia coli infection pathogenesis in a murine menopause model

    Get PDF
    Recurrent urinary tract infections (UTIs), primarily caused by uropathogenic Escherichia coli (UPEC), annually affect over 13 million patients in the United States. Menopausal women are disproportionally susceptible, suggesting estrogen deficiency is a significant risk factor for chronic and recurrent UTI. How estrogen status governs susceptibility to UTIs remains unknown, and whether hormone therapy protects against UTIs remains controversial. Here, we used a mouse model of surgical menopause by ovariectomy and demonstrate a protective role for estrogen in UTI pathogenesis. We found that ovariectomized mice had significantly higher bacteriuria, a more robust inflammatory response, and increased production of the proinflammatory cytokine interleukin-6 (IL-6) upon UPEC infection compared to sham-operated controls. We further show that response of the urothelial stem cell niche to infection, normally activated to restore homeostasis after infection, was aberrant in ovariectomized mice with defective superficial urothelial cell differentiation. Finally, UPEC-infected ovariectomized mice showed a significant increase in quiescent intracellular bacterial reservoirs, which reside in the urothelium and can seed recurrent infections. Importantly, this and other ovariectomy-induced outcomes of UTI were reversible upon estrogen supplementation. Together, our findings establish ovariectomized mice as a model for UTIs in menopausal women and pinpoint specific events during course of infection that are most susceptible to estrogen deficiency. These findings have profound implications for the understanding of the role of estrogen and estrogen therapy in bladder health and pathogen defense mechanisms and open the door for prophylaxis for menopausal women with recurrent UTIs

    The morphological dependent Tully-Fisher relation of spiral galaxies

    Full text link
    The Tully-Fisher relation of spiral galaxies shows notable dependence on morphological types, with earlier type spirals having systematically lower luminosity at fixed maximum rotation velocity VmaxV_{max}. This decrement of luminosity is more significant in shorter wavelengths. By modeling the rotation curve and stellar population of different morphological type spiral galaxies in combination, we find the VmaxV_{max} of spiral galaxies is weakly dependent on the morphological type, whereas the difference of the stellar population originating from the bulge disk composition effect mainly account for the morphological type dependence of the Tully-Fisher relation.Comment: 8 pages, 3 figures, ApJ accepte

    Implications of C1q/TNF-related protein superfamily in patients with coronary artery disease.

    Get PDF
    The C1q complement/TNF-related protein superfamily (CTRPs) displays differential effects on the regulation of metabolic homeostasis, governing cardiovascular function. However, whether and how they may serve as predictor/pro-diagnosis factors for assessing the risks of coronary artery disease (CAD) remains controversial. Therefore, we performed a clinical study to elaborate on the implication of CTRPs (CTRP1, CTRP5, CTRP7, and CTRP15) in CAD. CTRP1 were significantly increased, whereas CTRP7 and CTRP15 levels were decreased in CAD patients compared to the non-CAD group. Significant differences in CTRP1 levels were discovered between the single- and triple-vascular-vessel lesion groups. ROC analysis revealed that CTRP7 and CTRP15 may serve as CAD markers, while CTRP1 may serve as a marker for the single-vessel lesion of CAD. CTRP1 and CTRP5 can serve as markers for the triple-vessel lesion. CTRP1 may serve as an independent risk predictor for triple-vessel lesion, whereas CTRP15 alteration may serve for a single-vessel lesion of CAD. CTRP1 may serve as a novel superior biomarker for diagnosis of severity of vessel-lesion of CAD patients. CTRP7, CTRP15 may serve as more suitable biomarker for the diagnosis of CAD patients, whereas CTRP5 may serve as an independent predictor for CAD. These findings suggest CTRPs may be the superior predictive factors for the vascular lesion of CAD and represent novel therapeutic targets against CAD

    Valence band offset of InN/BaTiO3 heterojunction measured by X-ray photoelectron spectroscopy

    Get PDF
    X-ray photoelectron spectroscopy has been used to measure the valence band offset of the InN/BaTiO(3 )heterojunction. It is found that a type-I band alignment forms at the interface. The valence band offset (VBO) and conduction band offset (CBO) are determined to be 2.25 ± 0.09 and 0.15 ± 0.09 eV, respectively. The experimental VBO data is well consistent with the value that comes from transitivity rule. The accurate determination of VBO and CBO is important for use of semiconductor/ferrroelectric heterojunction multifunctional devices

    PSR J1926-0652: A Pulsar with Interesting Emission Properties Discovered at FAST

    Get PDF
    We describe PSR J1926-0652, a pulsar recently discovered with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). Using sensitive single-pulse detections from FAST and long-term timing observations from the Parkes 64-m radio telescope, we probed phenomena on both long and short time scales. The FAST observations covered a wide frequency range from 270 to 800 MHz, enabling individual pulses to be studied in detail. The pulsar exhibits at least four profile components, short-term nulling lasting from 4 to 450 pulses, complex subpulse drifting behaviours and intermittency on scales of tens of minutes. While the average band spacing P3 is relatively constant across different bursts and components, significant variations in the separation of adjacent bands are seen, especially near the beginning and end of a burst. Band shapes and slopes are quite variable, especially for the trailing components and for the shorter bursts. We show that for each burst the last detectable pulse prior to emission ceasing has different properties compared to other pulses. These complexities pose challenges for the classic carousel-type models.Comment: 13pages with 12 figure
    corecore