Metabolic flexibility is impaired in women who are pregnant and overweight/obese and related to insulin resistance and inflammation.

CONTEXT: Maternal obesity is a significant public health concern that contributes to unfavorable outcomes such as inflammation and insulin resistance. Women with obesity may have impaired metabolic flexibility (i.e. an inability to adjust substrate metabolism according to fuel availability). Impaired metabolic flexibility during pregnancy may mediate poor pregnancy outcomes in women with obesity. PURPOSE: The purposes of this study were to: 1) compare metabolic flexibility between overweight/obese and lean women; and 2) determine the relationships between metabolic flexibility, inflammation following a high-fat meal, and maternal metabolic health outcomes (i.e. gestational weight gain and insulin resistance). PROCEDURES: This interventional physiology study assessed lipid oxidation rates via indirect calorimetry before and after consumption of a high-fat meal. The percent change in lipid metabolism was calculated to determine 'metabolic flexibility.' Maternal inflammatory profiles (CRP, IL-6, IL-8, IL-10, IL-12, TNF-α) and insulin resistance (HOMA-IR) were determined via plasma analyses. MAIN FINDINGS: 64 women who were pregnant (lean = 35, overweight/obese = 29) participated between 32 and 38 weeks gestation. Lean women had significantly higher metabolic flexibility compared to overweight/obese women (lean 48.0 ±â€¯34.1% vs overweight/obese 29.3 ±â€¯34.3%, p = .035). Even when controlling for pre-pregnancy BMI, there was a negative relationship between metabolic flexibility and percent change in CRP among the overweight/obese group (r = -0.526, p = .017). Metabolic flexibility (per kg fat free mass) was negatively correlated with postprandial HOMA-IR (2 h: r = -0.325, p = .016; 4 h: r = -0.319, p = .019). CONCLUSIONS: Overweight and obese women who are pregnant are less 'metabolically flexible' than lean women, and this is related to postprandial inflammation and insulin resistance.

Borrelia burgdorferi in small mammal reservoirs in Kentucky, a traditionally non-endemic state for Lyme disease.

The incidence of tick-borne zoonoses such as Lyme disease has steadily increased in the southeastern United States. Southeastern states accounted for 1500 of over 28,000 confirmed cases of Lyme disease reported in the United States during 2015. Borrelia burgdorferi, the etiologic agent of Lyme disease, is maintained in small mammal reservoirs and vectored to new hosts by ixodid ticks. This study examined ecological relationships of the B. burgdorferi/vector/reservoir system in order to understand the dynamics of Lyme disease risk in Kentucky. Small mammals were captured using live traps from November 2014 to October 2015. Ticks were removed and blood and tissue collected from small mammals were screened for B. burgdorferi DNA by PCR with primers specific to the OspA gene. Prevalence of B. burgdorferi (21.8%) in Kentucky small mammals was comparable to the lowest recorded prevalence in regions where Lyme disease is endemic. Moreover, infestation of small mammals by Ixodes scapularis, the primary vector of B. burgdorferi, was rare, while Dermacentor variabilis comprised the majority of ticks collected. These findings provide ecological insight into the relative paucity of Lyme disease in Kentucky.

Genome Sequences of Subcluster K5 Mycobacteriophages AlleyCat, Edugator, and Guillsminger.

Bacteriophages AlleyCat, Edugator, and Guillsminger were isolated on Mycobacterium smegmatis mc2155 from enriched soil samples. All are members of mycobacteriophage subcluster K5, with genomes of 62,112 to 63,344 bp. Each genome contains 92 to 99 predicted protein-coding genes and one tRNA. Guillsminger is the first mycobacteriophage to carry an IS1380 family transposon.

In Silico characterization of phosphorylase kinase: evidence for an alternate intronic polyadenylation site in PHKG1.

Phosphorylase kinase (PhK), the key enzyme that regulates glycogenolysis, has traditionally been thought to be expressed predominantly in muscle and liver. In this study, we show by two different database searches (Expressed Sequence Tag and UniGene) that PhK gene expression occurs in at least 28-36 different tissues, and that the genes encoding the alpha, beta, and gamma subunits of PhK undergo extensive transcriptional processing. In particular, we have identified exon 6 of PHKG1 as a 3' composite terminal exon due to the presence of a weak polyadenylation and cleavage site in intron 6. We have verified biochemically that transcriptional processing of PHKG1 does occur in vivo; mRNA corresponding to the alternate variant is expressed in skeletal muscle, brain, heart, and tongue. In silico translation of this mRNA yields a PhK gamma subunit that contains the first 181 residues of the protein, followed by an additional 21 amino acids. The implication of this alternate processing is discussed within the context of gamma catalysis and regulation.