The Acute Satellite Cell Response and Skeletal Muscle Hypertrophy following Resistance Training

The extent of skeletal muscle hypertrophy in response to resistance training is highly variable in humans. The main objective of this study was to explain the nature of this variability. More specifically, we focused on the myogenic stem cell population, the satellite cell (SC) as a potential mediator of hypertrophy. Twenty-three males (aged 18–35 yrs) participated in 16 wk of progressive, whole body resistance training, resulting in changes of 7.9±1.6% (range of −1.9–24.7%) and 21.0±4.0% (range of −7.0 to 51.7%) in quadriceps volume and myofibre cross-sectional area (CSA), respectively. The SC response to a single bout of resistance exercise (80% 1RM), analyzed via immunofluorescent staining resulted in an expansion of type II fibre associated SC 72 h following exercise (pre: 11.3±0.9; 72 h: 14.8±1.4 SC/type II fibre; p<0.05). Training resulted in an expansion of the SC pool associated with type I (pre: 10.7±1.1; post: 12.1±1.2 SC/type I fibre; p<0.05) and type II fibres (pre: 11.3±0.9; post: 13.0±1.2 SC/type II fibre; p<0.05). Analysis of individual SC responses revealed a correlation between the relative change in type I associated SC 24 to 72 hours following an acute bout of resistance exercise and the percentage increase in quadriceps lean tissue mass assessed by MRI (r2 = 0.566, p = 0.012) and the relative change in type II associated SC following 16 weeks of resistance training and the percentage increase in quadriceps lean tissue mass assessed by MRI (r2 = 0.493, p = 0.027). Our results suggest that the SC response to resistance exercise is related to the extent of muscular hypertrophy induced by training

Non-canonical Keap1-independent activation of Nrf2 in astrocytes by mild oxidative stress

The transcription factor Nrf2 is a stress-responsive master regulator of antioxidant, detoxification and proteostasis genes. In astrocytes, Nrf2-dependent gene expression drives cell-autonomous cytoprotection and also non-cell-autonomous protection of nearby neurons, and can ameliorate pathology in several acute and chronic neurological disorders associated with oxidative stress. However, the value of astrocytic Nrf2 as a therapeutic target depends in part on whether Nrf2 activation by disease-associated oxidative stress occludes the effect of any Nrf2-activating drug. Nrf2 activation classically involves the inhibition of interactions between Nrf2's Neh2 domain and Keap1, which directs Nrf2 degradation. Keap1 inhibition is mediated by the modification of cysteine residues on Keap1, and can be triggered by electrophilic small molecules such as tBHQ. Here we show that astrocytic Nrf2 activation by oxidative stress involves Keap1-independent non-canonical signaling. Keap1 deficiency elevates basal Nrf2 target gene expression in astrocytes and occludes the effects of tBHQ, oxidative stress still induced strong Nrf2-dependent gene expression in Keap1-deficient astrocytes. Moreover, while tBHQ prevented protein degradation mediated via Nrf2's Neh2 domain, oxidative stress did not, consistent with a Keap1-independent mechanism. Moreover the effects of oxidative stress and tBHQ on Nrf2 target gene expression are additive, not occlusive. Mechanistically, oxidative stress enhances the transactivation potential of Nrf2's Neh5 domain in a manner dependent on its Cys-191 residue. Thus, astrocytic Nrf2 activation by oxidative stress involves Keap1-independent non-canonical signaling, meaning that further Nrf2 activation by Keap1-inhibiting drugs may be a viable therapeutic strategy

Paternal obesity is associated with IGF2 hypomethylation in newborns: results from a Newborn Epigenetics Study (NEST) cohort

Data from epidemiological and animal model studies suggest that nutrition during pregnancy may affect the health status of subsequent generations. These transgenerational effects are now being explained by disruptions at the level of the epigenetic machinery. Besides in vitro environmental exposures, the possible impact on the reprogramming of methylation profiles at imprinted genes at a much earlier time point, such as during spermatogenesis or oogenesis, has not previously been considered. In this study, our aim was to determine associations between preconceptional obesity and DNA methylation profiles in the offspring, particularly at the differentially methylated regions (DMRs) of the imprinted Insulin-like Growth Factor 2 (IGF2) gene

Vulnerability assessment and feasibility analysis of seismic strengthening of school buildings

The majority of structures in seismic-prone areas worldwide are structures that have been designed either without seismic design considerations, or using codes of practice that are seriously inadequate in the light of current seismic design principles. In Cyprus, after a series of earthquakes that occurred between 1995 and 1999, it was decided to carry out an unprecedented internationally seismic retrofitting of all school buildings, taking into account the sensitivity of the society towards these structures. In this paper representative school buildings are analysed in both their pristine condition and after applying retrofitting schemes typical of those implemented in the aforementioned large-scale strengthening programme. Non-linear analysis is conducted on calibrated analytical models of the selected buildings and fragility curves are derived for typical reinforced concrete and unreinforced masonry structures. These curves are then used to carry out a feasibility study, including both benefit-cost and life-cycle analysis, and evaluate the effectiveness of the strengthening programme

Are Bone and Muscle Changes from POWER PE, an 8-month In-school Jumping Intervention, Maintained at Three Years?

Our aim was to determine if the musculoskeletal benefits of a twice-weekly, school-based, jumping regime in healthy adolescent boys and girls were maintained three years later. Subjects of the original POWER PE trial (n = 99) were contacted and asked to undergo retesting three years after cessation of the intervention. All original measures were completed including: sitting height, standing height, weight, calcaneal broadband ultrasound attenuation (BUA), whole body, hip and spine bone mineral content (BMC), lean tissue mass, and fat mass. Physical activity was recorded with the bone-specific physical activity questionnaire (BPAQ) and calcium intake was estimated with a calcium-focussed food questionnaire. Maturity was determined by Tanner staging and estimation of the age of peak height velocity (PHV). Twenty-nine adolescents aged 17.3±0.4 years agreed to participate. Three years after the intervention, there were no differences in subject characteristics between control and intervention groups (p>0.05). Three-year change in weight, lean mass, and fat mass were similar between groups (p>0.05). There were no significant group differences in three-year change in BUA or BMC at any site (p>0.05), although the between-group difference in femoral neck BMC at follow-up exceeded the least significant change. While significant group differences were not observed three years after cessation of the intervention, changes in bone parameters occurred in parallel for intervention and control groups such that the original benefits of the intervention observed within the treatment group were sustained

Cerebrovascular reactivity among native-raised high altitude residents: an fMRI study

Background: The impact of long term residence on high altitude (HA) on human brain has raised concern among researchers in recent years. This study investigated the cerebrovascular reactivity among native-born high altitude (HA) residents as compared to native sea level (SL) residents. The two groups were matched on the ancestral line, ages, gender ratios, and education levels. A visual cue guided maximum inspiration task with brief breath holding was performed by all the subjects while Blood-Oxygenation-Level-Dependent (BOLD) functional Magnetic Resonance Imaging (fMRI) data were acquired from them

The cost-effectiveness of the WINGS intervention: a program to prevent HIV and sexually transmitted diseases among high-risk urban women

BACKGROUND: We evaluated the cost-effectiveness of the WINGS project, an intervention to prevent HIV and other sexually transmitted diseases among urban women at high risk for sexual acquisition of HIV. METHODS: We used standard methods of cost-effectiveness analysis. We conducted a retrospective analysis of the intervention's cost and we used a simplified model of HIV transmission to estimate the number of HIV infections averted by the intervention. We calculated cost-effectiveness ratios for the complete intervention and for the condom use skills component of the intervention. RESULTS: Under base case assumptions, the intervention prevented an estimated 0.2195 new cases of HIV at a cost of $215,690 per case of HIV averted. When indirect costs of HIV were excluded from the analysis, the intervention's cost-effectiveness ratios were$357,690 per case of HIV averted and $31,851 per quality-adjusted life year (QALY) saved. Under base case assumptions, the condom use skills component of the intervention prevented an estimated 0.1756 HIV infections and was cost-saving. When indirect HIV costs were excluded, the cost-effectiveness ratios for the condom use skills component of the intervention were$97,404 per case of HIV averted and $8,674 per QALY saved. CONCLUSIONS: The WINGS intervention, particularly the two sessions of the intervention which focussed on condom use skills, could be cost-effective in preventing HIV among women

Management of chronic obstructive pulmonary disease in India: a systematic review.

OBJECTIVES: Chronic diseases are fast becoming the largest health burden in India. Despite this, their management in India has not been well studied. We aimed to systematically review the nature and efficacy of current management strategies for chronic obstructive pulmonary disease (COPD) in India. METHODS: We used database searches (MEDLINE, EMBASE, IndMED, CENTRAL and CINAHL), journal hand-searches, scanning of reference lists and contact with experts to identify studies for systematic review. We did not review management strategies aimed at chronic diseases more generally, nor management of acute exacerbations. Due to the heterogeneity of reviewed studies, meta-analysis was not appropriate. Thus, narrative methods were used. SETTING: India. PARTICIPANTS: All adult populations resident in India. MAIN OUTCOME MEASURES: 1. Trialled interventions and outcomes 2. Extent and efficacy of current management strategies 3. Above outcomes by subgroup. RESULTS: We found information regarding current management - particularly regarding the implementation of national guidelines and primary prevention - to be minimal. This led to difficulty in interpreting studies of management strategies, which were varied and generally of positive effect. Data regarding current management outcomes were very few. CONCLUSIONS: The current understanding of management strategies for COPD in India is limited due to a lack of published data. Determination of the extent of current use of management guidelines, availability and use of treatment, and current primary prevention strategies would be useful. This would also provide evidence on which to interpret existing and future studies of management outcomes and novel interventions

Lunar resources: a review

There is growing interest in the possibility that the resource base of the Solar System might in future be used to supplement the economic resources of our own planet. As the Earth’s closest celestial neighbour, the Moon is sure to feature prominently in these developments. In this paper I review what is currently known about economically exploitable resources on the Moon, while also stressing the need for continued lunar exploration. I find that, although it is difficult to identify any single lunar resource that will be sufficiently valuable to drive a lunar resource extraction industry on its own (notwithstanding claims sometimes made for the 3He isotope, which are found to be exaggerated), the Moon nevertheless does possess abundant raw materials that are of potential economic interest. These are relevant to a hierarchy of future applications, beginning with the use of lunar materials to facilitate human activities on the Moon itself, and progressing to the use of lunar resources to underpin a future industrial capability within the Earth-Moon system. In this way, gradually increasing access to lunar resources may help ‘bootstrap’ a space-based economy from which the world economy, and possibly also the world’s environment, will ultimately benefit

Socioeconomic and physical distance to the maternity hospital as predictors for place of delivery: an observation study from Nepal

BACKGROUND: Although the debate on the safety and women's right of choice to a home delivery vs. hospital delivery continues in the developed countries, an undesirable outcome of home delivery, such as high maternal and perinatal mortality, is documented in developing countries. The objective was to study whether socio-economic factors, distance to maternity hospital, ethnicity, type and size of family, obstetric history and antenatal care received in present pregnancy affected the choice between home and hospital delivery in a developing country. METHODS: This cross-sectional study was done during June, 2001 to January 2002 in an administratively and geographically well-defined territory with a population of 88,547, stretching from urban to adjacent rural part of Kathmandu and Dhading Districts of Nepal with maximum of 5 hrs of distance from Maternity hospital. There were no intermediate level of private or government hospital or maternity homes in the study area. Interviews were carried out on 308 women who delivered within 45 days of the date of the interview with a pre-tested structured questionnaire. RESULTS: A distance of more than one hour to the maternity hospital (OR = 7.9), low amenity score status (OR = 4.4), low education (OR = 2.9), multi-parity (OR = 2.4), and not seeking antenatal care in the present pregnancy (OR = 4.6) were statistically significantly associated with an increased risk of home delivery. Ethnicity, obstetric history, age of mother, ritual observance of menarche, type and size of family and who is head of household were not statistically significantly associated with the place of delivery. CONCLUSIONS: The socio-economic standing of the household was a stronger predictor of place of delivery compared to ethnicity, the internal family structure such as type and size of family, head of household, or observation of ritual days by the mother of an important event like menarche. The results suggested that mothers, who were in the low-socio-economic scale, delivered at home more frequently in a developing country like Nepal