The Benefits and Costs of Head Start

In this essay we review what is known about Head Start and argue that the program is likely to generate benefits to participants and society as a whole that are large enough to justify the program's costs. Our conclusions differ importantly from those offered in some previous reviews because we use a more appropriate standard to judge the success of Head Start (namely, benefit-cost analysis), draw on new accumulating evidence for Head Start's long-term effects on early cohorts of program participants, and discuss why common interpretations of a recent randomized experimental evaluation of Head Start's short-term impacts may be overly pessimistic. While in principle there could be more beneficial ways of deploying Head Start resources, the benefits of such changes remain uncertain and there is some downside risk.

The natural history of subjective tinnitus in adults: a systematic review and meta-analysis of ‘no-intervention’ periods in controlled trials

Objectives Tinnitus is a prevalent condition, but little has been published regarding the natural history of the condition. One technique for evaluating the long-term progression of the disease is to examine what happens to participants in the no-intervention control arm of a clinical trial. The aim of this study was to examine no-intervention or waiting-list data reported in trials, in which participants on the active arm received any form of tinnitus intervention. Data Sources CINAHL, PsychINFO, EMBASE, ASSIA, PubMed, Web of Science, Science Direct, EBSCO Host, and Cochrane. Methods Inclusion criteria followed the PICOS principles: Participants, adults with tinnitus; Intervention, none; Control, any intervention for alleviating tinnitus; Outcomes, a measure assessing tinnitus symptoms using a multi-item patient-reported tinnitus questionnaire. Secondary outcome measures included multi-item patient-reported questionnaires of mood and health-related quality of life and measures that quantified change in tinnitus loudness; Study design, randomized controlled trials or observational studies utilizing a no-intervention or waiting-list control group. Data were extracted and standardized mean difference was calculated for each study to enable meta-analysis. Results The evidence strongly favored a statistically significant decrease in the impact of tinnitus over time, though there was significant heterogeneity and clinical significance cannot be interpreted. Outcome data regarding secondary measures did not demonstrate any clinically significant change. Conclusions Participants allocated to the no-intervention or waiting-list control arm of clinical trials for a tinnitus intervention show a small but significant improvement in self-reported measures of tinnitus with time; the clinical significance of this finding is unknown. There is, however, considerable variation across individuals. These findings support previous work and can cautiously be used when counseling patients

Puzzling It Out: The Current State of Scientific Knowledge on Pre-Kindergarten Effects - A Consensus Statement

Scientific research has established that if all children are to achieve their developmental potential, it is important to lay the foundation during the earliest years for lifelong health, learning, and positive behavior. A central question is how well our public pre-kindergarten (pre-K) programs are doing to build this foundation.Forty-two states and the District of Columbia, through 57 pre-K programs, have introduced substantial innovations in their early education systems by developing the infrastructure, program sites, and workforce required to accommodate pre-K education. These programs now serve nearly 30 percent of the nation's 4-year-olds and 5 percent of 3-year-olds

Heschl's gyrus is more sensitive to tone level than non-primary auditory cortex

Previous neuroimaging studies generally demonstrate a growth in the cortical response with an increase in sound level. However, the details of the shape and topographic location of such growth remain largely unknown. One limiting methodological factor has been the relatively sparse sampling of sound intensities. Additionally, most studies have either analysed the entire auditory cortex without differentiating primary and non-primary regions or have limited their analyses to Heschl's gyrus (HG). Here, we characterise the pattern of responses to a 300-Hz tone presented in 6-dB steps from 42 to 96 dB sound pressure level as a function of its sound level, within three anatomically defined auditory areas; the primary area, on HG, and two non-primary areas, consisting of a small area lateral to the axis of HG (the anterior lateral area, ALA) and the posterior part of auditory cortex (the planum temporale, PT). Extent and magnitude of auditory activation increased non-linearly with sound level. In HG, the extent and magnitude were more sensitive to increasing level than in ALA and PT. Thus, HG appears to have a larger involvement in sound-level processing than does ALA or PT

Comparative analyses of proteins from Haemophilus influenzae biofilm and planktonic populations using metabolic labeling and mass spectrometry

BACKGROUND: Non-typeable H. influenzae (NTHi) is a nasopharyngeal commensal that can become an opportunistic pathogen causing infections such as otitis media, pneumonia, and bronchitis. NTHi is known to form biofilms. Resistance of bacterial biofilms to clearance by host defense mechanisms and antibiotic treatments is well-established. In the current study, we used stable isotope labeling by amino acids in cell culture (SILAC) to compare the proteomic profiles of NTHi biofilm and planktonic organisms. Duplicate continuous-flow growth chambers containing defined media with either “light” (L) isoleucine or “heavy” (H) (13)C(6)-labeled isoleucine were used to grow planktonic (L) and biofilm (H) samples, respectively. Bacteria were removed from the chambers, mixed based on weight, and protein extracts were generated. Liquid chromatography-mass spectrometry (LC-MS) was performed on the tryptic peptides and 814 unique proteins were identified with 99% confidence. RESULTS: Comparisons of the NTHi biofilm to planktonic samples demonstrated that 127 proteins showed differential expression with p-values ≤0.05. Pathway analysis demonstrated that proteins involved in energy metabolism, protein synthesis, and purine, pyrimidine, nucleoside, and nucleotide processes showed a general trend of downregulation in the biofilm compared to planktonic organisms. Conversely, proteins involved in transcription, DNA metabolism, and fatty acid and phospholipid metabolism showed a general trend of upregulation under biofilm conditions. Selected reaction monitoring (SRM)-MS was used to validate a subset of these proteins; among these were aerobic respiration control protein ArcA, NAD nucleotidase and heme-binding protein A. CONCLUSIONS: The present proteomic study indicates that the NTHi biofilm exists in a semi-dormant state with decreased energy metabolism and protein synthesis yet is still capable of managing oxidative stress and in acquiring necessary cofactors important for biofilm survival. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12866-014-0329-9) contains supplementary material, which is available to authorized users

Ethanolic extract of Jatropha gossypifolia exacerbates Potassium Bromate-induced clastogenicity, hepatotoxicity, and lipid peroxidation in rats

Extracts of J. gossypifolia L. have been reported to have several medicinal values, including potential anti-cancer and anti-inflammatory properties. In this study, we investigated the anti-clastogenic and hepatoprotective, effects of the ethanolic leaf extract of J. gossypifolia L. in potassium bromate (KBrO3)-induced toxicity in rats. The general trend of the results indicates significant increases (p < 0.05) in mean values when toxicant (KBrO3) only group is compared with normal control group, except for catalase where a significant decrease (p < 0.05) was recorded. Surprisingly, treatment of the toxic effects of KBrO3 by J. gossypifolia did not lower the mean values of any of these parameters investigated. Instead, there were significant increases (p < 0.05) in the mean number of bone marrow micronucleated polychromatic erythrocytes (mPCEs), plasma malondialdehyde (MDA) concentration, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and gamma glutamyl transferase activities, and sodium, while the increases in mean concentrations of creatinine, urea, and potassium were not significant (p > 0.05). Also, there was a further reduction in the activity of catalase by J. gossypifolia treatment, and was also not significant (p > 0.05). We therefore concluded that the ethanolic leaf extract of J. gossypifolia may not have a protective role against chromosomal and liver damage in KBrO3-induced toxicity, but complicating effects.Keywords: Jatropha gossypifolia, KBrO3, ethanolic extract, toxicity, rat

The targeted delivery of multicomponent cargos to cancer cells by nanoporous particle-supported lipid bilayers.

Encapsulation of drugs within nanocarriers that selectively target malignant cells promises to mitigate side effects of conventional chemotherapy and to enable delivery of the unique drug combinations needed for personalized medicine. To realize this potential, however, targeted nanocarriers must simultaneously overcome multiple challenges, including specificity, stability and a high capacity for disparate cargos. Here we report porous nanoparticle-supported lipid bilayers (protocells) that synergistically combine properties of liposomes and nanoporous particles. Protocells modified with a targeting peptide that binds to human hepatocellular carcinoma exhibit a 10,000-fold greater affinity for human hepatocellular carcinoma than for hepatocytes, endothelial cells or immune cells. Furthermore, protocells can be loaded with combinations of therapeutic (drugs, small interfering RNA and toxins) and diagnostic (quantum dots) agents and modified to promote endosomal escape and nuclear accumulation of selected cargos. The enormous capacity of the high-surface-area nanoporous core combined with the enhanced targeting efficacy enabled by the fluid supported lipid bilayer enable a single protocell loaded with a drug cocktail to kill a drug-resistant human hepatocellular carcinoma cell, representing a 10(6)-fold improvement over comparable liposomes