Weight Gain in College Freshmen: Emerging Adulthood and Health Responsibility

Background and Purpose: College freshmen gain weight at double the rate of same-age peers, and personal, interpersonal, and situational factors play a role in this phenomenon. The objectives of the study were to quantify weight change in first semester college students and to identify predictors of weight gain. Methods: In fall 2011, 76 unmarried freshmen, living in dormitories at a public, southwestern U.S. university, participated in the study. Heights and weights were measured at the beginning and end of the semester, and an on-line survey was administered at both times. Results: In the first semester of college, 43% gained clinically significant weight (> 3.5 pounds) and 15% gained more than 10 pounds. The group at highest risk was students with a normal BMI; 50% of this cohort gained clinically significant weight. Two variables predicted 12% of weight gain: a low level of health responsibility and a normal BMI. Conclusion: For college freshmen at highest risk of precipitous weight gain, health promotion strategies aimed at maximizing health responsibility is needed. Additionally, an integration of mediating influences related to the developmental stage of emerging adulthood, such as perceived social norms, positive peer influence and self-efficacy may result in improved long-term lifestyle practices

Effectiveness of community outreach and engagement in recruitment success for a prebirth cohort.

IntroductionWe describe the effectiveness of community outreach and engagement in supporting recruitment for the US National Children's Vanguard Study between 2009 and 2012.MethodsThirty-seven study locations used 1 of 4 strategies to recruit 18-49-year-old pregnant or trying to conceive women: (1) Initial Vanguard Study used household-based recruitment; (2) Direct Outreach emphasized self-referral; (3) Enhanced Household-Based Recruitment enhanced Initial Vanguard Study strategies; and (4) Provider-Based Recruitment recruited through healthcare providers. Outreach and engagement included advance letters, interactions with healthcare providers, participation in community events, contacts with community organizations, and media outreach.ResultsAfter 1-2 years, 41%-74% of 9844 study-eligible women had heard about the National Children's Vanguard Study when first approached. Women who heard were 1.5-3 times more likely to consent. Hearing via word-of-mouth or the media most frequently predicted consent. The more sources women heard from the higher the odds of consent.ConclusionsWe conclude that tailored outreach and engagement facilitate recruitment in cohort studies

Hepatitis C viral evolution in genotype 1 treatment-naïve and treatment-experienced patients receiving telaprevir-based therapy in clinical trials

Background: In patients with genotype 1 chronic hepatitis C infection, telaprevir (TVR) in combination with peginterferon and ribavirin (PR) significantly increased sustained virologic response (SVR) rates compared with PR alone. However, genotypic changes could be observed in TVR-treated patients who did not achieve an SVR. Methods: Population sequence analysis of the NS3•4A region was performed in patients who did not achieve SVR with TVR-based treatment. Results: Resistant variants were observed after treatment with a telaprevir-based regimen in 12% of treatment-naïve patients (ADVANCE; T12PR arm), 6% of prior relapsers, 24% of prior partial responders, and 51% of prior null responder patients (REALIZE, T12PR48 arms). NS3 protease variants V36M, R155K, and V36M+R155K emerged frequently in patients with genotype 1a and V36A, T54A, and A156S/T in patients with genotype 1b. Lower-level resistance to telaprevir was conferred by V36A/M, T54A/S, R155K/T, and A156S variants; and higher-level resistance to telaprevir was conferred by A156T and V36M+R155K variants. Virologic failure during telaprevir treatment was more common in patients with genotype 1a and in prior PR nonresponder patients and was associated with higher-level telaprevir-resistant variants. Relapse was usually associated with wild-type or lower-level resistant variants. After treatment, viral populations were wild-type with a median time of 10 months for genotype 1a and 3 weeks for genotype 1b patients. Conclusions: A consistent, subtype-dependent resistance profile was observed in patients who did not achieve an SVR with telaprevir-based treatment. The primary role of TVR is to inhibit wild-type virus and variants with lower-levels of resistance to telaprevir. The complementary role of PR is to clear any remaining telaprevir-resistant variants, especially higher-level telaprevir-resistant variants. Resistant variants are detectable in most patients who fail to achieve SVR, but their levels decline over time after treatment

Greenhouse gas production in degrading ice-rich permafrost deposits in northeastern Siberia

Permafrost deposits have been a sink for atmospheric carbon for millennia. Thaw-erosional processes, however, can lead to rapid degradation of ice-rich permafrost and the release of substantial amounts of organic carbon (OC). The amount of the OC stored in these deposits and their potential to be microbially decomposed to the greenhouse gases carbon dioxide (CO2) and methane (CH4) depends on climatic and environmental conditions during deposition and the decomposition history before incorporation into the permafrost. Here, we examine potential greenhouse gas production in degrading ice-rich permafrost deposits from three locations in the northeast Siberian Laptev Sea region. The deposits span a period of about 55 kyr from the last glacial period and Holocene interglacial. Samples from all three locations were incubated under aerobic and anaerobic conditions for 134 days at 4 °C. Greenhouse gas production was generally higher in deposits from glacial periods, where 0.2–6.1% of the initially available OC was decomposed to CO2. In contrast, only 0.1–4.0% of initial OC were decomposed in permafrost deposits from the Holocene and the late glacial transition. Within the deposits from the Kargin interstadial period (Marine Isotope Stage 3), local depositional environments, especially soil moisture, also affected the preservation of OC. Sediments deposited under wet conditions contained more labile OC and thus produced more greenhouse gases than sediments deposited under drier conditions. To assess the greenhouse gas production potentials over longer periods, deposits from two locations were incubated for a total of 785 days. However, more than 50% of total CO2 production over 785 days occurred within the first 134 days under aerobic conditions while even 80% were produced over the same period under anaerobic conditions, which emphasizes the non-linearity of the OC decomposition processes. Methanogenesis was generally observed in active layer samples but only sporadically in permafrost samples and was several orders of magnitude smaller than CO2 production

Sensitivity of CSM-CERES-Maize model to soil available water and impact on rainfed maize grown in the Brazilian Cerrado.

The response of maize to variations in soil available water (AW) is a function of the interactions among plant, soil and weather conditions. We studied the sensitivity of a previously calibrated CSM-CERES-Maize model and the response of rainfed maize grain yield to soil AW. The study was conducted for conditions in southeast Brazil. The model was set for weekly sowings, from August to September, for a total of 52 sowing dates. At each sowing date, six scenarios of soil AW using field capacity estimated at -4 kPa, -6 kPa, -10 kPa, -20 kPa, -33 kPa and determined in situ, were used. For each sowing date, the model was also set for rainfall reductions of 10%, 20%, 30%, 40% and 50%. The simulated results showed the sensitivity of the model to soil AW, which in turn affected grain yield of maize among sowing dates. For the highest yielding sowing date, a reduction of 48.3% in average grain yield was simulated with soil AW using FC at -4 kPa and FC at -33 kPa. Additionally, our simulations indicated significant correlation between grain yield and total crop evapotranspiration and between grain yield and maximum leaf area index. Scenarios of low rainfall had little effect on yield with high soil AW. Therefore, our simulations indicate that accurate information on FC is needed for the simulation of maize grown under rainfed conditions. Our simulations also indicate that the best sowing window for maize in southeastern Brazil ranges from Oct 17 to Nov 28

Impact of climate change on maize grown in the brazilian cerrado.

Crops are subject to instabilities of climatic conditions that affect yield. Maize is very sensitive to factors like temperature, solar radiation and rainfall. The objective of this work was to evaluate, using crop growth models, the effects of climate change on maize grain yield produced under rainfed conditions. Two global circulation models, HadGEM2-ES and MIROC5, coupled to the regional model Eta, were used to generate projections of changes in maximum and minimum air temperature, solar radiation and rainfall for conditions in southeastern Brazil. The CSM-CERES-Maize model was then used to evaluate the effect of climate changes on rainfed maize grain yield. For each combination of global and regional circulation models, two greenhouse gas concentration scenarios were used: RCP4.5 and RCP8.5. The combined use of global circulation and crop growth models allowed us to estimate the expected average grain yield of corn as affected by future climate. The simulated results indicated that, even at best sowing dates, considerable reduction in maize grain yield may occur. Our simulated results also indicated that the largest grain yield reductions may occur for future climate scenarios from 2071 to the end of the 21st century

Role of Endothelial Progenitor Cells and Inflammatory Cytokines in Healing of Diabetic Foot Ulcers

Background: To evaluate changes in endothelial progenitor cells (EPCs) and cytokines in patients with diabetic foot ulceration (DFU) in association with wound healing. Methods: We studied healthy subjects, diabetic patients not at risk of DFU, at risk of DFU and with active DFU. We prospectively followed the DFU patients over a 12-week period. We also investigated similar changes in diabetic rabbit and mouse models of wound healing. Results: All EPC phenotypes except the kinase insert domain receptor (KDR)+CD133+ were reduced in the at risk and the DFU groups compared to the controls. There were no major EPC differences between the control and not at risk group, and between the at risk and DFU groups. Serum stromal-cell derived factor-1 (SDF-1) and stem cell factor (SCF) were increased in DFU patients. DFU patients who healed their ulcers had lower CD34+KDR+ count at visits 3 and 4, serum c-reactive protein (CRP) and granulocyte-macrophage colony-stimulating factor (GM-CSF) at visit 1, interleukin-1 (IL-1) at visits 1 and 4. EPCs tended to be higher in both diabetic animal models when compared to their non-diabetic counterparts both before and ten days after wounding. Conclusions: Uncomplicated diabetes does not affect EPCs. EPCs are reduced in patients at risk or with DFU while complete wound healing is associated with CD34+KDR+ reduction, suggesting possible increased homing. Low baseline CRP, IL-1α and GM-CSF serum levels were associated with complete wound healing and may potentially serve as prognostic markers of DFU healing. No animal model alone is representative of the human condition, indicating the need for multiple experimental models