7 research outputs found
which marker is best for prediction? Pooled analysis of four German population-based cohort studies and comparison with a nationwide cohort study
Objective To compare the association between different anthropometric
measurements and incident type 2 diabetes mellitus (T2DM) and to assess their
predictive ability in different regions of Germany. Methods Data of 10 258
participants from 4 prospective population-based cohorts were pooled to assess
the association of body weight, body mass index (BMI), waist circumference
(WC), waist-to-hip-ratio (WHR) and waist-to-height-ratio (WHtR) with incident
T2DM by calculating HRs of the crude, adjusted and standardised markers, as
well as providing receiver operator characteristic (ROC) curves. Differences
between HRs and ROCs for the different anthropometric markers were calculated
to compare their predictive ability. In addition, data of 3105 participants
from the nationwide survey were analysed separately using the same methods to
provide a nationally representative comparison. Results Strong associations
were found for each anthropometric marker and incidence of T2DM. Among the
standardised anthropometric measures, we found the strongest effect on
incident T2DM for WC and WHtR in the pooled sample (HR for 1 SD difference in
WC 1.97, 95% CI 1.75 to 2.22, HR for WHtR 1.93, 95% CI 1.71 to 2.17 in women)
and in female DEGS participants (HR for WC 2.24, 95% CI 1.91 to 2.63, HR for
WHtR 2.10, 95% CI 1.81 to 2.44), whereas the strongest association in men was
found for WHR among DEGS participants (HR 2.29, 95% CI 1.89 to 2.78). ROC
analysis showed WHtR to be the strongest predictor for incident T2DM.
Differences in HR and ROCs between the different markers confirmed WC and WHtR
to be the best predictors of incident T2DM. Findings were consistent across
study regions and age groups (<65 vs ≥65 years). Conclusions We found stronger
associations between anthropometric markers that reflect abdominal obesity
(ie, WC and WHtR) and incident T2DM than for BMI and weight. The use of these
measurements in risk prediction should be encouraged
Anthropometric markers and their association with incident type 2 diabetes mellitus: which marker is best for prediction? Pooled analysis of four German population-based cohort studies and comparison with a nationwide cohort study
Objective: To compare the association between different anthropometric measurements and incident type 2 diabetes mellitus (T2DM) and to assess their predictive ability in different regions of Germany. Methods: Data of 10 258 participants from 4 prospective population-based cohorts were pooled to assess the association of body weight, body mass index (BMI), waist circumference (WC), waist-to-hip-ratio (WHR) and waist-to-height-ratio (WHtR) with incident T2DM by calculating HRs of the crude, adjusted and standardised markers, as well as providing receiver operator characteristic (ROC) curves. Differences between HRs and ROCs for the different anthropometric markers were calculated to compare their predictive ability. In addition, data of 3105 participants from the nationwide survey were analysed separately using the same methods to provide a nationally representative comparison. Results: Strong associations were found for each anthropometric marker and incidence of T2DM. Among the standardised anthropometric measures, we found the strongest effect on incident T2DM for WC and WHtR in the pooled sample (HR for 1 SD difference in WC 1.97, 95% CI 1.75 to 2.22, HR for WHtR 1.93, 95% CI 1.71 to 2.17 in women) and in female DEGS participants (HR for WC 2.24, 95% CI 1.91 to 2.63, HR for WHtR 2.10, 95% CI 1.81 to 2.44), whereas the strongest association in men was found for WHR among DEGS participants (HR 2.29, 95% CI 1.89 to 2.78). ROC analysis showed WHtR to be the strongest predictor for incident T2DM. Differences in HR and ROCs between the different markers confirmed WC and WHtR to be the best predictors of incident T2DM. Findings were consistent across study regions and age groups
High level expression of a recombinant amylosucrase gene and selected properties of the enzyme.
Two high-level heterologous expression systems for amylosucrase genes have been constructed. One depends on sigma-70 bacterial RNA polymerase, the other on phage T7 RNA polymerase. Translational fusions were formed between slightly truncated versions of the gene from Neisseria polysaccharea and sequences of expression vectors pQE-81L or pET33b(+), respectively. These constructs were introduced into different Escherichia coli strains. The resulting recombinants yielded up to 170 mg of dissolved enzyme per litre of culture at a moderate cell density of five OD(600). To our knowledge, this is the highest yield per cell described so far for amylosucrases. The recombinant enzymes could rapidly be purified through the use of histidine tags in the N-terminally attached sequences. These segments did not alter catalytic properties and therefore need not be removed for most applications. Investigations with glucose and malto-oligosaccharides of different lengths identified rate-limiting steps in the elongation (acceptor reaction) and truncation (donor reaction) of these substrates. The elongation of maltotriose and its reversal, the truncation of maltotetraose, were found to be particularly slow reactions. Potential reasons are discussed, based on the crystal structure of the enzyme. It is furthermore shown that amylosucrase is able to synthesise mixed disaccharides. All of the glucose epimers mannose, allose, and galactose served as acceptors, yielding between one and three main products. We also demonstrate that, as an alternative to the use of purified amylosucrase, cells of the constructed recombinant strains can be used to carry out glucosylations of acceptors