To distinguish pathogens from commensals, the intestinal epithelium employs cytosolic innate immune sensors. Activation of the NAIP-NLRC4 inflammasome initiates extrusion of infected intestinal epithelial cells (IEC) upon cytosolic bacterial sensing. We previously reported that activation of the inflammasome in tuft cells, which are primarily known for their role in parasitic infections, leads to the release of prostaglandin D2 (PGD2).
View Article and Find Full Text PDFThe intracellular human pathogen Shigella invades the colonic epithelium to cause disease. Prior to invasion, this bacterium navigates through different environments within the human body, including the stomach and the small intestine. To adapt to changing environments, Shigella uses the bacterial second messenger cyclic di-GMP (c di-GMP) signaling system, synthesized by diguanylate cyclases (DGCs) encoding GGDEF domains.
View Article and Find Full Text PDFThe intracellular human pathogen invades the colonic epithelium to cause disease. Prior to invasion, this bacterium navigates through different environments within the human body, including the stomach and the small intestine. To adapt to changing environments, uses the bacterial second messenger c-di-GMP signaling system, synthesized by diguanylate cyclases (DGCs) encoding GGDEF domains.
View Article and Find Full Text PDFMultidrug-resistant (MDR) (Mtb) poses significant challenges to global tuberculosis (TB) control efforts. Host-directed therapies (HDTs) offer a novel approach to TB treatment by enhancing immune-mediated clearance of Mtb. Prior preclinical studies found that the inhibition of heme oxygenase-1 (HO-1), an enzyme involved in heme metabolism, with tin-protoporphyrin IX (SnPP) significantly reduced mouse lung bacillary burden when co-administered with the first-line antitubercular regimen.
View Article and Find Full Text PDFHost cytosolic sensing of Mycobacterium tuberculosis (M. tuberculosis) RNA by the RIG-I-like receptor (RLR) family perturbs innate immune control within macrophages; however, a distinct role of MDA5, a member of the RLR family, in M. tuberculosis pathogenesis has yet to be fully elucidated.
View Article and Find Full Text PDFMultidrug-resistant (MDR) (Mtb) poses significant challenges to global tuberculosis (TB) control efforts. Host-directed therapies (HDT) offer a novel approach for TB treatment by enhancing immune-mediated clearance of Mtb. Prior preclinical studies found that inhibition of heme oxygenase-1 (HO-1), an enzyme involved in heme metabolism, with tin-protoporphyrin IX (SnPP) significantly reduced mouse lung bacillary burden when co-administered with the first-line antitubercular regimen.
View Article and Find Full Text PDFDespite numerous advances in tuberculosis (TB) drug development, long treatment durations have led to the emergence of multidrug resistance, which poses a major hurdle to global TB control. Shortening treatment time therefore remains a top priority. Host-directed therapies that promote bacterial clearance and/or lung health may improve the efficacy and treatment duration of tuberculosis antibiotics.
View Article and Find Full Text PDFFollowing infection with , the causative agent of tuberculosis (TB), most human hosts are able to contain the infection and avoid progression to active TB disease through expression of a balanced, homeostatic immune response. Proinflammatory mechanisms aiming to kill, slow and sequester the pathogen are key to a successful host response. However, an excessive or inappropriate pro-inflammatory response may lead to granuloma enlargement and tissue damage, which may prolong the TB treatment duration and permanently diminish the lung function of TB survivors.
View Article and Find Full Text PDFLow thyroid hormone (TH) conditions caused by a variety of prenatal and perinatal problems have been shown to alter postnatal regulatory thyrotropin (TSH) responsiveness to TH in humans and rodents. The mechanisms underlying this pituitary TH resistance remain unknown. Here we use the evolutionarily conserved zebrafish model to examine the effects of low TH on thyrotrope development and function.
View Article and Find Full Text PDFNaturally occurring cell death is essential to the development of the mammalian nervous system. Although the importance of developmental cell death has been appreciated for decades, there is no comprehensive account of cell death across brain areas in the mouse. Moreover, several regional sex differences in cell death have been described for the ventral forebrain and hypothalamus, but it is not known how widespread the phenomenon is.
View Article and Find Full Text PDFThe circadian mutation duper in Syrian hamsters shortens the free-running circadian period (τ(DD)) by 2 hours when expressed on a tau mutant (τ(ss)) background and by 1 hour on a wild-type background. We have examined the effects of this mutation on phase response curves and entrainment. In contrast to wild types, duper hamsters entrained to 14L:10D with a positive phase angle.
View Article and Find Full Text PDFThree animals born to homozygous tau mutant (τ(ss), "super short") Syrian hamsters showed extremely short free-running periods of locomotor activity (τ(DD) of approximately 17.8 hours). Inbreeding produced 33 such "super duper" animals, which had a τ(DD) of 18.
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