Systematic review of interventions designed to reduce screen time in children and adolescents

This descriptive systematic review describes intervention trials for children and youth that targeted screen time (ST) as a way to prevent or control obesity and measured ST, and at least one of the following: physical activity, dietary intake, and adiposity. Both “hands-on” (e.g., video games) and “hands free” (e.g., television viewing) ST were included. Published, completed intervention trials (k=12), not-yet-published, completed trials (k=6), and in-progress trials (k=11) were identified through searches of electronic databases, including trial registries and bibliographies of eligible study reports. Study characteristics of the 29 identified trials were coded and presented in evidence tables. Considerable attention was paid to the type of ST addressed, measures used, and the type of interventions. Based on the number of in-progress and not-yet-published trials, the number of completed, published reports will double in the next three years. Most of the studies were funded by federal sources. General populations, not restricted by race, gender, or weight status, were targets of most interventions with children ages 9-12 yeas as the modal age group. Most trials used randomized control trials in which the majority of control or comparison group received an intervention. The mean number of participants was 242.8 (SD=314.7) and interventions were delivered over an average of 10.5 months and consisted of approximately 16 sessions, with a total time of about eight hours. The majority of completed trials evaluate each of the four constructs, however, most studies have more than one measure to assess each construct (e.g., BMI and tricep skinfold thickness to evaluate adiposity) and rarely did studies use the same measures. This is likely why the majority of studies produced at least one significant intervention effect on each outcome that was assessed. The four major outcomes should be evaluated in all interventions attempting to reduce screen time in order to determine the mechanisms involved that may contribute to obesity. More importantly researchers should work together to determine the best measures to evaluate the four main constructs to allow studies to be compared. Another area for consensus is the definition of ST. ^

Strategies for obesity prevention in child care settings: A literature review

Background. Children in the age group of 2-5 years spend substantial amount of time during the day in some kind of childcare setting. These settings are an excellent environmental infrastructure to enhance their nutrition and physical activity behavior and to promote healthy eating and physical activity habits. Due to the steep rise in overweight and obesity among children in the past three decades, it becomes essential to intervene early. There exists a need for literature on a comprehensive and sustainable approach to obesity prevention for younger children in these settings. ^ Methods. Systematic literature search was undertaken using databases like Medline Ovid, Pubmed, Medline Ebsco, and Cochrane Library. Articles published in English as well as English language abstracts of foreign articles were included. The inclusion criteria were as follows: (1) Studies conducted in any part of the world exploring relevant themes and a child care or preschool setting would be included. (2) The interventions promoted physical activity, nutrition/healthy eating/improved diet, reduced television viewing, reduced BMI, changed knowledge and behavior of children and or staff or affected policy/standards/regulations. (3) The population was children in the age group of at least 2 years to 5 years. (4) Articles published in English and English language abstracts for foreign articles would be included. ^ Results. 16 articles were included in the review that consisted of primary interventions in the form of randomized control trials or pre-post interventions were conducted in a preschool or child care or day care setting only. The outcomes pertaining to healthy weight in children were increased vegetable intake, reduced BMI and increased knowledge among others. ^ Conclusion. There is a dearth of data on strong intervention trials in the child care setting. Preschool research studies in the young children that have been conducted are not strong enough. There is a need for more randomized control trials and a well planned evaluation in the preschool age children. There is a need to develop outcome measures that can accurately assess the changes in diet and physical activity in this age group. Child care nutrition and physical activity standards need to be made stringent. ^

A systematic review of community-based colorectal cancer screening randomized controlled trials with multi-ethnic groups

Background. The CDC estimates that 40% of adults 50 years of age or older do not receive time-appropriate colorectal cancer screening. Sixty percent of colorectal cancer deaths could be prevented by regular screening of adults 50 years of age and older. Yet, in 2000 only 42.5% of adults age 50 or older in the U.S. had received recommended screening. Disparities by health care, nativity status, socioeconomic status, and race/ethnicity are evident. Disparities in minority, underserved populations prevent us from attaining Goal 2 of Healthy People 2010 to “eliminate health disparities.” This review focuses on community-based screening research among underserved populations that includes multiple ethnic groups for appropriate disparities analysis. There is a gap in the colorectal cancer screening literature describing the effectiveness of community-based randomized controlled trials. ^ Objective. To critically review the literature describing community-based colorectal cancer screening strategies that are randomized controlled trials, and that include multiple racial/ethnic groups. ^ Methods. The review includes a preliminary disparities analysis to assess whether interventions were appropriately targeted in communities to those groups experiencing the greatest health disparities. Review articles are from an original search using Ovid Medline and a cross-matching search in Pubmed, both from January 2001 to June 2009. The Ovid Medline literature review is divided into eight exclusionary stages, seven electronic, and the last stage consisting of final manual review. ^ Results. The final studies (n=15) are categorized into four categories: Patient mailings (n=3), Telephone outreach (n=3), Electronic/multimedia (n=4), and Counseling/community education (n=5). Of 15 studies, 11 (73%) demonstrated that screening rates increased for the intervention group compared to controls, including all studies (100%) from the Patient mailings and Telephone outreach groups, 4 of 5 (80%) Counseling/community education studies, and 1 of 4 (25%) Electronic/multimedia interventions. ^ Conclusions. Patient choice and tailoring education and/or messages to individuals have proven to be two important factors in improving colorectal cancer screening adherence rates. Technological strategies have not been overly successful with underserved populations in community-based trials. Based on limited findings to date, future community-based colorectal cancer screening trials should include diverse populations who are experiencing incidence, survival, mortality and screening disparities. ^

Procedure for the identification of population characteristics for targeting intervention services on the basis of outcome-goal priorities: Case management services for the chronic mentally ill

Although the processes involved in rational patient targeting may be obvious for certain services, for others, both the appropriate sub-populations to receive services and the procedures to be used for their identification may be unclear. This project was designed to address several research questions which arise in the attempt to deliver appropriate services to specific populations. The related difficulties are particularly evident for those interventions about which findings regarding effectiveness are conflicting. When an intervention clearly is not beneficial (or is dangerous) to a large, diverse population, consensus regarding withholding the intervention from dissemination can easily be reached. When findings are ambiguous, however, conclusions may be impossible.^ When characteristics of patients likely to benefit from an intervention are not obvious, and when the intervention is not significantly invasive or dangerous, the strategy proposed herein may be used to identify specific characteristics of sub-populations which may benefit from the intervention. The identification of these populations may be used both in further informing decisions regarding distribution of the intervention and for purposes of planning implementation of the intervention by identifying specific target populations for service delivery.^ This project explores a method for identifying such sub-populations through the use of related datasets generated from clinical trials conducted to test the effectiveness of an intervention. The method is specified in detail and tested using the example intervention of case management for outpatient treatment of populations with chronic mental illness. These analyses were applied in order to identify any characteristics which distinguish specific sub-populations who are more likely to benefit from case management service, despite conflicting findings regarding its effectiveness for the aggregate population, as reported in the body of related research. However, in addition to a limited set of characteristics associated with benefit, the findings generated, a larger set of characteristics of patients likely to experience greater improvement without intervention. ^

Differential Activity of the KRAS Oncogene by Method of Activation: Implications for Signaling and Therapeutic Intervention

Despite having been identified over thirty years ago and definitively established as having a critical role in driving tumor growth and predicting for resistance to therapy, the KRAS oncogene remains a target in cancer for which there is no effective treatment. KRas is activated b y mutations at a few sites, primarily amino acid substitutions at codon 12 which promote a constitutively active state. I have found that different amino acid substitutions at codon 12 can activate different KRas downstream signaling pathways, determine clonogenic growth potential and determine patient response to molecularly targeted therapies. Computer modeling of the KRas structure shows that different amino acids substituted at the codon 12 position influences how KRas interacts with its effecters. In the absence of a direct inhibitor of mutant KRas several agents have recently entered clinical trials alone and in combination directly targeting two of the common downstream effecter pathways of KRas, namely the Mapk pathway and the Akt pathway. These inhibitors were evaluated for efficacy against different KRAS activating mutations. An isogenic panel of colorectal cells with wild type KRas replaced with KRas G12C, G12D, or G12V at the endogenous loci differed in sensitivity to Mek and Akt inhibition. In contrast, screening was performed in a broad panel of lung cell lines alone and no correlation was seen between types of activating KRAS mutation due to concurrent oncogenic lesions. To find a new method to inhibit KRAS driven tumors, siRNA screens were performed in isogenic lines with and without active KRas. The knockdown of CNKSR1 (CNK1) showed selective growth inhibition in cells with an oncogenic KRAS. The deletion of CNK1 reduces expression of mitotic cell cycle proteins and arrests cells with active KRas in the G1 phase of the cell cycle similar to the deletion of an activated KRas regardless of activating substitution. CNK1 has a PH domain responsible for localizing it to membrane lipids making KRas potentially amenable to inhibition with small molecules. The work has identified a series of small molecules capable of binding to this PH domain and inhibiting CNK1 facilitated KRas signaling.