Chemicals and Drugs Commons^™

Pubertal Lipid Levels Are Significantly Lower In Youth With Type 1 Diabetes Who Experienced Partial Clinical Remission, Benjamin U. Nwosu, Shwetha Rupendu, Emily Zitek-Morrison, Deepa Patel, Tony R. Villalobos-Ortiz, Gabrielle Jasmin, Bruce A. Barton

Benjamin U. Nwosu

Importance: The physiologic changes in lipids during puberty in type 1 diabetes (T1D) is unclear as subjects in previous studies were not stratified by partial clinical remission (PCR) status.

Aim: To determine the effect of PCR on lipid changes during puberty in youth with T1D.

Subjects and Methods: A retrospective cross-sectional study of 194 subjects consisting of 71 controls of age 12.9±1.3y and 123 subjects with T1D stratified into remitters (n=44, age 13.0±0.8y) and non-remitters (n=79, age 11.2±0.6y). PCR was defined as insulin-dose adjusted HbA1c of ≤9. Pubertal status was determined by Tanner staging.

Results: Among the pubertal cohort, low-density …

Children With Type 1 Diabetes Who Experienced A Honeymoon Phase Had Significantly Lower Ldl Cholesterol 5 Years After Diagnosis, Benjamin U. Nwosu, Bo Zhang, Sanaa S. Ayyoub, Stephanie Choi, Tony R. Villalobos-Ortiz, Laura C. Alonso, Bruce A. Barton

Benjamin U. Nwosu

IMPORTANCE: Landmark studies showed that partial clinical remission in new-onset type 1 diabetes is associated with reduced prevalence of long-term complications, but early clinical indicators of this favorable outcome are poorly characterized.

AIM: To determine if there were any differences in lipid parameters, especially LDL-cholesterol, between remitters and non-remitters 4 to 5 years after the diagnosis of type 1 diabetes after controlling for hemoglobin A1c, body mass index, and pubertal status.

SUBJECTS AND METHODS: A longitudinal retrospective cohort study of 123 subjects of mean age 11.9 +/- 2.9 years, [male 11.7 +/- 2.9 years, (n = 55); female 12.0 +/- …

The Effect Of All-Trans Retinoic Acid And Fatty Acids On Mcf-7 Breast Cancer Cell Progression, David Brown

David C. Brown

Vitamin A metabolites and retinoids may slow the progression of breast cancer and elicit anti-neoplastic properties similar to those of omega-3 fatty acids. Studies using animal models show a decrease in the incidence, growth and metastisis of mammary tumors in the presence of specific fatty acids. This effect is also seen with use of retinoids, specifically all-trans retinoic acid (AtRA). Thus, fatty acids may also alter retinoid homeostasis in mammary carcinoma cells (MCF-7s). The potential for inter/co dependency among fatty acids and retinoids is considerable, and here it has been hypothesized that a decrease in cancer progression will occur in …

Cloning And Characterization Of The Escherichia Coli Heptosyltransferase Iii: Exploring Substrate Specificity In Lipopolysaccaride Core Biosynthesis, Jagadesh Mudapaka, Erika Taylor

Erika A. Taylor, Ph.D.

Bacterial lipopolysaccharide (LPS) molecules are an important cell surface component that enables adhesion to surfaces and cell motility, amongst other functions. In Escherichia coli, there are multiple Heptosyltransferase enzymes involved in the biosynthesis of the core region of LPS. Here we describe the first ever cloning, expression, purification and characterization of Heptosyltransferase III (HepIII) from E. coli, which catalyzes the addition of an l-glycero-d-manno-heptose (Hep) residue to the growing LPS core via an α(1→7) bond. Inspired by results from our lab on the E. coli HepI, we assessed the catalytic efficiency with phospho-Hep2-Kdo2-Lipid A (PH2K2LA) and two deacylated analogues.

Lipopolysaccharide Biosynthesis Without The Lipids: Substrate Recognition For Escherichia Coli Heptosyltransferasei, Daniel J. Czyzyk, Cassie Liu, Erika A. Taylor

Erika A. Taylor, Ph.D.

Heptosyltransferase I (HepI) is responsible for the transfer of l-glycero-d-manno-heptose to a 3-deoxy-α-D-oct-2-ulopyranosonic acid (Kdo) of the growing core region of lipopolysaccharide (LPS). The catalytic efficiency of HepI with the fully deacylated analogue of Escherichia coli HepI LipidA is 12-fold greater than with the fully acylated substrate, with a k(cat)/K(m) of 2.7 × 10(6) M(-1) s(-1), compared to a value of 2.2 × 10(5) M(-1) s(-1) for the Kdo(2)-LipidA substrate. Not only is this is the first demonstration that an LPS biosynthetic enzyme is catalytically enhanced by the absence of lipids, this result has significant implications for downstream enzymes that …