The genetic and molecular basis of flagellar motility has been investigated for several decades, with innovative research strategies propelling advances at a steady pace. Furthermore, as the ...phenomenon is examined in diverse bacteria, new taxon-specific regulatory and structural features are being elucidated. Motility is also a straightforward bacterial phenotype that can allow undergraduate researchers to explore the palette of molecular genetic tools available to microbiologists. This study, driven primarily by undergraduate researchers, evaluated hundreds of flagellar motility mutants in the Gram-negative plant-associated bacterium Agrobacterium fabrum. The nearly saturating screen implicates a total of 37 genes in flagellar biosynthesis, including genes of previously unknown function.
The genetic and molecular basis of flagellar motility has been investigated for several decades, with innovative research strategies propelling advances at a steady pace. Furthermore, as the ...phenomenon is examined in diverse bacteria, new taxon-specific regulatory and structural features are being elucidated. Motility is also a straightforward bacterial phenotype that can allow undergraduate researchers to explore the palette of molecular genetic tools available to microbiologists. This study, driven primarily by undergraduate researchers, evaluated hundreds of flagellar motility mutants in the Gram-negative plant-associated bacterium Agrobacterium fabrum. The nearly saturating screen implicates a total of 37 genes in flagellar biosynthesis, including genes of previously unknown function.
ABSTRACT BACKGROUND Emerging links between household cleaning products and childhood overweight may involve the gut microbiome. We determined mediating effects of infant gut microbiota on ...associations between home use of cleaning products and future overweight. METHODS From the Canadian Healthy Infant Longitudinal Development (CHILD) birth cohort, we tested associations between maternal report of cleaning product use and overweight at age 3, and whether associations were mediated by microbial profiles of fecal samples in 3- to 4-month-old infants. RESULTS Among 757 infants, the abundance of specific gut microbiota was associated with household cleaning with disinfectants and eco-friendly products in a dose-dependent manner. With more frequent use of disinfectants, Lachnospiraceae increasingly became more abundant (highest v. lowest quintile of use: adjusted odds ratio AOR 1.93, 95% confidence interval CI 1.08 to 3.45) while genus Haemophilus declined in abundance (highest v. lowest quintile of use: AOR 0.36, 95% CI 0.20 to 0.65). Enterobacteriaceae were successively depleted with greater use of eco-friendly products (AOR 0.45, 95% CI 0.27 to 0.74). Lachnospiraceae abundance significantly mediated associations of the top 30th centile of household disinfectant use with higher body mass index (BMI) z score ( p = 0.02) and with increased odds of overweight or obesity ( p = 0.04) at age 3. Use of eco-friendly products was associated with decreased odds of overweight or obesity independently of Enterobacteriaceae abundance (AOR 0.44, 95% CI 0.22 to 0.86), with no significant mediation ( p = 0.2). INTERPRETATION Exposure to household disinfectants was associated with higher BMI at age 3, mediated by gut microbial composition at age 3–4 months. Although child overweight was less common in households that cleaned with eco-friendly products, the lack of mediation by infant gut microbiota suggests another pathway for this association.
Aims/hypothesis
While the use of insulin pumps in paediatrics has expanded dramatically, there is still considerable variability among countries in the use of pump technology. The present study ...sought to describe differences in metabolic control and pump use in young people with type 1 diabetes using data collected in three multicentre registries.
Methods
Data for the years 2011 and 2012 from 54,410 children and adolescents were collected from the Prospective Diabetes Follow-up Registry (DPV;
n
= 26,198), T1D Exchange (T1DX;
n
= 13,755) and the National Paediatric Diabetes Audit (NPDA;
n
= 14,457). The modality of insulin delivery, based on age, sex and ethnic minority status, and the impact of pump use on HbA
1c
levels were compared.
Results
The overall mean HbA
1c
level was higher in the NPDA (8.9 ± 1.6% 74 ± 17.5 mmol/mol) than in the DPV (8.0 ± 1.6% 64 ± 17.0 mmol/mol,
p <
0.001) and T1DX (8.3 ± 1.4% 68 ± 15.4 mmol/mol,
p <
0.001). Conversely, pump use was much lower in the NPDA (14%) than in the DPV (41%,
p <
0.001) and T1DX (47%,
p <
0.001). In a pooled analysis, pump use was associated with a lower mean HbA
1c
(pump: 8.0 ± 1.2% 64 ± 13.3 mmol/mol vs injection: 8.5 ± 1.7% 69 ± 18.7 mmol/mol,
p <
0.001). In all three registries, those with an ethnic minority status were less likely to be treated with a pump (
p <
0.001) and boys were treated with a pump less often compared with girls (
p <
0.001).
Conclusions/interpretation
Despite similar clinical characteristics and proportion of minority participants, substantial differences in metabolic control exist across the three large transatlantic registries of paediatric patients with type 1 diabetes, which appears to be due in part to the frequency of insulin pump therapy.
Traumatic brain injury (TBI) is a major cause of death and disability in the United States, exacting a debilitating physical, social, and financial strain. Therefore, it is crucial to examine the ...impact of TBI on medically underserved communities in the U.S. The purpose of the current study was to review the literature on TBI for evidence of racial/ethnic differences in the U.S. Results of the review showed significant racial/ethnic disparities in TBI outcome and several notable differences in other TBI variables. American Indian/Alaska Natives have the highest rate and number of TBI-related deaths compared with all other racial/ethnic groups; Blacks/African Americans are significantly more likely to incur a TBI from violence when compared with Non-Hispanic Whites; and minorities are significantly more likely to have worse functional outcome compared with Non-Hispanic Whites, particularly among measures of community integration. We were unable to identify any studies that looked directly at underlying racial/ethnic biological variations associated with different TBI outcomes. In the absence of studies on racial/ethnic differences in TBI pathobiology, taking an indirect approach, we looked for studies examining racial/ethnic differences in oxidative stress and inflammation outside the scope of TBI as they are known to heavily influence TBI pathobiology. The literature indicates that Blacks/African Americans have greater inflammation and oxidative stress compared with Non-Hispanic Whites. We propose that future studies investigate the possibility of racial/ethnic differences in inflammation and oxidative stress within the context of TBI to determine whether there is any relationship or impact on TBI outcome.
The Hymenoptera Genome Database (HGD) is a comprehensive model organism database that caters to the needs of scientists working on insect species of the order Hymenoptera. This system implements ...open-source software and relational databases providing access to curated data contributed by an extensive, active research community. HGD contains data from 9 different species across ~200 million years in the phylogeny of Hymenoptera, allowing researchers to leverage genetic, genome sequence and gene expression data, as well as the biological knowledge of related model organisms. The availability of resources across an order greatly facilitates comparative genomics and enhances our understanding of the biology of agriculturally important Hymenoptera species through genomics. Curated data at HGD includes predicted and annotated gene sets supported with evidence tracks such as ESTs/cDNAs, small RNA sequences and GC composition domains. Data at HGD can be queried using genome browsers and/or BLAST/PSI-BLAST servers, and it may also be downloaded to perform local searches. We encourage the public to access and contribute data to HGD at: http://HymenopteraGenome.org.
Fat-soluble vitamers (FSV) are a class of diverse organic substances important in a wide range of biological processes, including immune function, vision, bone health, and coagulation. Profiling FSV ...in parents and children enables insights into gene-environment contributions to their circulating levels, but no studies have reported on the population epidemiology of FSV in these groups as of yet. In this study, we report distributions of FSV, their parent-child concordance and variation by key characteristics for 2490 children (aged 11-12 years) and adults (aged 28-71 years) in the Child Health CheckPoint of the Longitudinal Study of Australian Children. Ten A, D, E and K vitamers were quantified using a novel automated LC-MS/MS method. All three K vitamers (i.e., K1, MK-4, MK-7) and 1-α-25(OH)
D
were below the instrument detection limit and were removed from the present analysis. We observed a strong vitamer-specific parent-child concordance for the six quantifiable A, D and E FSVs. FSV concentrations all varied by age, BMI, and sex. We provide the first cross-sectional population values for multiple FSV. Future studies could examine relative genetic vs. environmental determinants of FSV, how FSV values change longitudinally, and how they contribute to future health and disease.
Celiac disease (CD) has a recognized association with type 1 diabetes. We examined international differences in CD prevalence and clinical characteristics of youth with coexisting type 1 diabetes and ...CD versus type 1 diabetes only.
Data sources were as follows: the Prospective Diabetes Follow-up Registry (DPV) (Germany/Austria); the T1D Exchange Clinic Network (T1DX) (U.S.); the National Paediatric Diabetes Audit (NPDA) (U.K. England/Wales); and the Australasian Diabetes Data Network (ADDN) (Australia). The analysis included 52,721 youths <18 years of age with a clinic visit between April 2013 and March 2014. Multivariable linear and logistic regression models were constructed to analyze the relationship between outcomes (HbA
, height SD score SDS, overweight/obesity) and type 1 diabetes/CD versus type 1 diabetes, adjusting for sex, age, and diabetes duration.
Biopsy-confirmed CD was present in 1,835 youths (3.5%) and was diagnosed at a median age of 8.1 years (interquartile range 5.3-11.2 years). Diabetes duration at CD diagnosis was <1 year in 37% of youths, >1-2 years in 18% of youths, >3-5 years in 23% of youths, and >5 years in 17% of youths. CD prevalence ranged from 1.9% in the T1DX to 7.7% in the ADDN and was higher in girls than boys (4.3% vs. 2.7%,
< 0.001). Children with coexisting CD were younger at diabetes diagnosis compared with those with type 1 diabetes only (5.4 vs. 7.0 years of age,
< 0.001) and fewer were nonwhite (15 vs. 18%,
< 0.001). Height SDS was lower in those with CD (0.36 vs. 0.48, adjusted
< 0.001) and fewer were overweight/obese (34 vs. 37%, adjusted
< 0.001), whereas mean HbA
values were comparable: 8.3 ± 1.5% (67 ± 17 mmol/mol) versus 8.4 ± 1.6% (68 ± 17 mmol/mol).
CD is a common comorbidity in youth with type 1 diabetes. Differences in CD prevalence may reflect international variation in screening and diagnostic practices, and/or CD risk. Although glycemic control was not different, the lower height SDS supports close monitoring of growth and nutrition in this population.
Diabetic ketoacidosis (DKA) in children and adolescents with established type 1 diabetes is a major problem with considerable morbidity, mortality, and associated costs to patients, families, and ...health care systems. We analyzed data from three multinational type 1 diabetes registries/audits with similarly advanced, yet differing, health care systems with an aim to identify factors associated with DKA admissions.
Data from 49,859 individuals <18 years with type 1 diabetes duration ≥1 year from the Prospective Diabetes Follow-up Registry (DPV) initiative (n = 22,397, Austria and Germany), the National Paediatric Diabetes Audit (NPDA; n = 16,314, England and Wales), and the T1D Exchange (T1DX; n = 11,148, U.S.) were included. DKA was defined as ≥1 hospitalization for hyperglycemia with a pH <7.3 during the prior year. Data were analyzed using multivariable logistic regression models.
The frequency of DKA was 5.0% in DPV, 6.4% in NPDA, and 7.1% in T1DX, with differences persisting after demographic adjustment (P < 0.0001). In multivariable analyses, higher odds of DKA were found in females (odds ratio OR 1.23, 99% CI 1.10-1.37), ethnic minorities (OR 1.27, 99% CI 1.11-1.44), and HbA1c ≥7.5% (≥58 mmol/mol) (OR 2.54, 99% CI 2.09-3.09 for HbA1c from 7.5 to <9% 58 to <75 mmol/mol and OR 8.74, 99% CI 7.18-10.63 for HbA1c ≥9.0% ≥75 mmol/mol).
These multinational data demonstrate high rates of DKA in childhood type 1 diabetes across three registries/audits and five nations. Females, ethnic minorities, and HbA1c above target were all associated with an increased risk of DKA. Targeted DKA prevention programs could result in substantial health care cost reduction and reduced patient morbidity and mortality.
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