A pragmatic cluster randomized clinical trial of diabetes prevention strategies for women with gestational diabetes: design and rationale of the Gestational Diabetes' Effects on Moms (GEM) study.

BACKGROUND: Women with gestational diabetes (GDM) are at high risk of developing diabetes later in life. After a GDM diagnosis, women receive prenatal care to control their blood glucose levels via diet, physical activity and medications. Continuing such lifestyle skills into early motherhood may reduce the risk of diabetes in this high risk population. In the Gestational Diabetes' Effects on Moms (GEM) study, we are evaluating the comparative effectiveness of diabetes prevention strategies for weight management designed for pregnant/postpartum women with GDM and delivered at the health system level. METHODS/DESIGN: The GEM study is a pragmatic cluster randomized clinical trial of 44 medical facilities at Kaiser Permanente Northern California randomly assigned to either the intervention or usual care conditions, that includes 2,320 women with a GDM diagnosis between March 27, 2011 and March 30, 2012. A Diabetes Prevention Program-derived print/telephone lifestyle intervention of 13 telephonic sessions tailored to pregnant/postpartum women was developed. The effectiveness of this intervention added to usual care is to be compared to usual care practices alone, which includes two pages of printed lifestyle recommendations sent to postpartum women via mail. Primary outcomes include the proportion of women who reach a postpartum weight goal and total weight change. Secondary outcomes include postpartum glycemia, blood pressure, depression, percent of calories from fat, total caloric intake and physical activity levels. Data were collected through electronic medical records and surveys at baseline (soon after GDM diagnosis), 6 weeks (range 2 to 11 weeks), 6 months (range 12 to 34 weeks) and 12 months postpartum (range 35 to 64 weeks). DISCUSSION: There is a need for evidence regarding the effectiveness of lifestyle modification for the prevention of diabetes in women with GDM, as well as confirmation that a diabetes prevention program delivered at the health system level is able to successfully reach this population. Given the use of a telephonic case management model, our Diabetes Prevention Program-derived print/telephone intervention has the potential to be adopted in other settings and to inform policies to promote the prevention of diabetes among women with GDM.

Referral to telephonic nurse management improves outcomes in women with gestational diabetes.

OBJECTIVE: We sought to determine whether, among women with gestational diabetes mellitus, referral to a telephonic nurse management program was associated with lower risk of macrosomia and increased postpartum glucose testing. STUDY DESIGN: There was medical center-level variation in the percent of patients referred to a telephonic nurse management program at 12 Kaiser Permanente medical centers, allowing us to examine in a quasi-experimental design the associations between referral and outcomes. RESULTS: Compared with women from centers where the annual proportion of referral nurse management was <30%, women who delivered from centers with an annual referral proportion >70% were less likely to have a macrosomic infant and more likely to have postpartum glucose testing (multiple-adjusted odds ratio, 0.75; 95% confidence interval, 0.57-0.98 and multiple-adjusted odds ratio, 22.96; 95% confidence interval, 2.56-3.42, respectively). CONCLUSION: Receiving care at the centers with higher referral frequency to telephonic nurse management for gestational diabetes mellitus was associated with decreased risk of macrosomic infant and increased postpartum glucose testing.

Mechanism of NS2B-mediated activation of NS3pro in dengue virus: molecular dynamics simulations and bioassays.

The NS2B cofactor is critical for proteolytic activation of the flavivirus NS3 protease. To elucidate the mechanism involved in NS2B-mediated activation of NS3 protease, molecular dynamic simulation, principal component analysis, molecular docking, mutagenesis, and bioassay studies were carried out on both the dengue virus NS3pro and NS2B-NS3pro systems. The results revealed that the NS2B-NS3pro complex is more rigid than NS3pro alone due to its robust hydrogen bond and hydrophobic interaction networks within the complex. These potent networks lead to remodeling of the secondary and tertiary structures of the protease that facilitates cleavage sequence recognition and binding of substrates. The cofactor is also essential for proper domain motion that contributes to substrate binding. Hence, the NS2B cofactor plays a dual role in enzyme activation by facilitating the refolding of the NS3pro domain as well as being directly involved in substrate binding/interactions. Kinetic analyses indicated for the first time that Glu92 and Asp50 in NS2B and Gln27, Gln35, and Arg54 in NS3pro may provide secondary interaction points for substrate binding. These new insights on the mechanistic contributions of the NS2B cofactor to NS3 activation may be utilized to refine current computer-based search strategies to raise the quality of candidate molecules identified as potent inhibitors against flaviviruses.

Signature Optical Cues: Emerging Technologies for Monitoring Plant Health.

Optical technologies can be developed as practical tools for monitoring plant health by providing unique spectral signatures that can be related to specific plant stresses. Signatures from thermal and fluorescence imaging have been used successfully to track pathogen invasion before visual symptoms are observed. Another approach for noninvasive plant health monitoring involves elucidating the manner with which light interacts with the plant leaf and being able to identify changes in spectral characteristics in response to specific stresses. To achieve this, an important step is to understand the biochemical and anatomical features governing leaf reflectance, transmission and absorption. Many studies have opened up possibilities that subtle changes in leaf reflectance spectra can be analyzed in a plethora of ways for discriminating nutrient and water stress, but with limited success. There has also been interest in developing transgenic phytosensors to elucidate plant status in relation to environmental conditions. This approach involves unambiguous signal creation whereby genetic modification to generate reporter plants has resulted in distinct optical signals emitted in response to specific stressors. Most of these studies are limited to laboratory or controlled greenhouse environments at leaf level. The practical translation of spectral cues for application under field conditions at canopy and regional levels by remote aerial sensing remains a challenge. The movement towards technology development is well exemplified by the Controlled Ecological Life Support System under development by NASA which brings together technologies for monitoring plant status concomitantly with instrumentation for environmental monitoring and feedback control.

The Comparative Effectiveness of Diabetes Prevention Strategies to Reduce Postpartum Weight Retention in Women With Gestational Diabetes Mellitus: The Gestational Diabetes' Effects on Moms (GEM) Cluster Randomized Controlled Trial.

OBJECTIVE: To compare the effectiveness of diabetes prevention strategies addressing postpartum weight retention for women with gestational diabetes mellitus (GDM) delivered at the health system level: mailed recommendations (usual care) versus usual care plus a Diabetes Prevention Program (DPP)-derived lifestyle intervention. RESEARCH DESIGN AND METHODS: This study was a cluster randomized controlled trial of 44 medical facilities (including 2,280 women with GDM) randomized to intervention or usual care. The intervention included mailed gestational weight gain recommendations plus 13 telephone sessions between 6 weeks and 6 months postpartum. Primary outcomes included the following: proportion meeting the postpartum goals of 1) reaching pregravid weight if pregravid BMI <25.0 kg/m(2) or 2) losing 5% of pregravid weight if BMI ≥25.0 kg/m(2); and pregravid to postpartum weight change. RESULTS: On average, over the 12-month postpartum period, women in the intervention had significantly higher odds of meeting weight goals than women in usual care (odds ratio [OR] 1.28 [95% CI 1.10, 1.47]). The proportion meeting weight goals was significantly higher in the intervention than usual care at 6 weeks (25.5 vs. 22.4%; OR 1.17 [1.01, 1.36]) and 6 months (30.6 vs. 23.9%; OR 1.45 [1.14, 1.83]). Condition differences were reduced at 12 months (33.0 vs. 28.0%; OR 1.25 [0.96, 1.62]). At 6 months, women in the intervention retained significantly less weight than women in usual care (mean 0.39 kg [SD 5.5] vs. 0.95 kg [5.5]; mean condition difference -0.64 kg [95% CI -1.13, -0.14]) and had greater increases in vigorous-intensity physical activity (mean condition difference 15.4 min/week [4.9, 25.8]). CONCLUSIONS: A DPP-derived lifestyle intervention modestly reduced postpartum weight retention and increased vigorous-intensity physical activity.

A His6-SUMO-eXact tag for producing human prepro-urocortin 2 in Escherichia coli for raising monoclonal antibodies.

This is a first report of recombinant production of human prepro-Urocortin 2 in Escherichia coli by N-terminal fusion with a triple His6-SUMO-eXact tag and its subsequent use as an antigen for the production and screening of very high affinity monoclonal antibodies. The rationale for this combinatorial construct is that the His tag allows first step protein purification of insoluble and soluble proteins, the SUMO tag enhances protein expression level and solubility, while the eXact tag facilitates anion-triggered on-column cleavage of the triple tag to recover pure native proteins in a simple two-step protein purification procedure. Compared with an eXact fusion alone, the presence of the SUMO moiety enhanced overall expression levels by 4 to 10 fold but not the solubility of the highly basic prepro-Urocortin 2. Insoluble SUMO-eXact-preproUCN2 was purified in milligram quantities by denaturing IMAC and solubilized in native phosphate buffer by on-column refolding or step-wise dialysis. Only a small fraction of this solubilized protein was able to bind onto the eXact™ affinity column and cleaved by NaF treatment. To test whether binding and cleavage failure was due to improperly refolded SUMO-eXact-preproUCN2 or to the presence of N- and C-terminal sequences flanking the eXact moiety, we created a SUMO-eXact-thioredoxin construct which was overexpressed mainly in the soluble form. This protein bound to and was cleaved efficiently on the eXact™ column to yield native thioredoxin. Solubilized SUMO-eXact-preproUCN2 was used successfully to generate two high affinity mouse monoclonal antibodies (KD~10⁻¹° and 10⁻¹¹ M) specific to the pro-region of Urocortin 2.

A pregnancy and postpartum lifestyle intervention in women with gestational diabetes mellitus reduces diabetes risk factors: a feasibility randomized control trial.

OBJECTIVE: To pilot, among women with gestational diabetes mellitus (GDM), the feasibility of a prenatal/postpartum intervention to modify diet and physical activity similar to the Diabetes Prevention Program. The intervention was delivered by telephone, and support for breastfeeding was addressed. RESEARCH DESIGN AND METHODS: The goal was to help women return to their prepregnancy weight, if it was normal, or achieve a 5% reduction from prepregnancy weight if overweight. Eligible participants were identified shortly after a GDM diagnosis; 83.8% consented to be randomly assigned to intervention or usual medical care (96 and 101 women, respectively). The retention was 85.2% at 12 months postpartum. RESULTS: The proportion of women who reached the postpartum weight goal was higher, although not statistically significant, in the intervention condition than among usual care (37.5 vs. 21.4%, absolute difference 16.1%, P=0.07). The intervention was more effective among women who did not exceed the recommended gestational weight gain (difference in the proportion of women meeting the weight goals: 22.5%, P=0.04). The intervention condition decreased dietary fat intake more than the usual care (condition difference in the mean change in percent of calories from fat: -3.6%, P=0.002) and increased breastfeeding, although not significantly (condition difference in proportion: 15.0%, P=0.09). No differences in postpartum physical activity were observed between conditions. CONCLUSIONS: This study suggests that a lifestyle intervention that starts during pregnancy and continues postpartum is feasible and may prevent pregnancy weight retention and help overweight women lose weight. Strategies to help postpartum women overcome barriers to increasing physical activity are needed.

Comparison of glyburide and insulin for the management of gestational diabetes in a large managed care organization.

OBJECTIVE: This study was undertaken to compare the use of glyburide with insulin for the treatment of gestational diabetes mellitus (GDM) unresponsive to diet therapy. STUDY DESIGN: A retrospective study was performed among women with singleton pregnancies who had GDM diagnosed, with fasting plasma glucose 140 mg/dL or less on glucose tolerance testing, between 12 and 34 weeks who failed diet therapy from 1999 to 2002. We identified 584 women and compared those treated with insulin between 1999 and 2000 with women treated with glyburide between 2001 and 2002. Maternal and neonatal outcomes and complications were assessed. Statistical methods included univariate analyses and multivariable logistic regression. RESULTS: In 1999 through 2000, 268 women had GDM diagnosed and were treated with insulin; in 2001 through 2002, 316 women had GDM diagnosed of which 236 (75%) received glyburide. The 2 groups were similar with regard to age, nulliparity, and historical GDM risk factors; however, women in the insulin group had a higher mean body mass index (31.9 vs 30.6 kg/m 2 , P=.04), a greater proportion identified themselves as white (43%, 28%, P<.001) and fewer as Asian (24%, 37%, P=.001), and they had a significantly higher mean fasting on glucose tolerance test (105.4 vs 102.4 mg/dL , P=.005) compared with the glyburide group. There were no significant differences in birth weight (3599+/-650 g vs 3661+/-629 g, P=.3), macrosomia (24%, 25%, P=.7), or cesarean delivery (35%, 39 %, P=.4). Women in the glyburide group had a higher incidence of preeclampsia (12%, 6%, P=.02), and neonates in the glyburide group were more likely to receive phototherapy (9%, 5%, P<.05), and less likely to be admitted to the neonatal intensive care unit (NICU) (15%, 24%, P=.008) though they had a longer NICU length of stay (4.3+/-9.6 vs 8.0+/-10.1, P=.002). Posttreatment glycemic control data were available for 122 women treated with insulin and 137 women treated with glyburide. More women in the glyburide group achieved mean fasting and postprandial goals (86%, 63%, P<.001). These findings remained significant in logistic regression analysis. CONCLUSION: In a large managed care organization, glyburide was at least as effective as insulin in achieving glycemic control and similar birth weights in women with GDM who failed diet therapy. The increased risk of preeclampsia and phototherapy in the glyburide group warrant further study.