Effects of exercise and food restriction on rat skeletal muscles.

Studies were undertaken to compare the effects of exercise and food restriction on body weight (BW), muscle weight (MW), muscle fiber size, and proportion of muscle fiber types. 20 male Fischer 344 rats were randomly assigned to four equal groups: ad libitum-fed control (AC), ad libitum-fed exercise (AE), food restricted control (RC) and food restricted exercise (RE). From 6 weeks of age, RC and RE rats received 60% of the daily food intake of AC and AE rats, respectively. At 7 months of age, AE and RE rats began 40-50 min of daily treadmill exercise. Running speed increased from 1.2 to 1.6 miles/hour and the grade increased to 15% during the first 2 weeks of training. After 10 weeks of training, rats were weighed, sacrificed, and the soleus (SOL), plantaris (PLN) and extensor digitorum longus (EDL) muscles were removed at in situ rest length, weighed, and quick-frozen. Standard histochemical assays were performed, and muscle fiber cross-sectional area was determined planimetrically. Training had little effect on MW or BW, but food restriction greatly reduced BW. This resulted in greater MW/BW ratio in RC and RE than AC and AE rats, respectively. Exercise also increased SOL muscle fiber area in ad libitum-fed but not food restricted rats resulting in smaller fibers in SOL of RE than AE. No changes in percentage of SOL fiber types occurred with food restriction or exercise. In PLN, the percentage of fast-twitch oxidative fibers of AE and RE was greater than in AC and RC, but there was no effect of food restriction or exercise on fiber area.(ABSTRACT TRUNCATED AT 250 WORDS)     

Highly efficient shoot regeneration of <Emphasis Type="Italic">Bacopa monnieri</Emphasis> (L.) using a two-stage culture procedure and assessment of genetic integrity of micropropagated plants by RAPD

A two-stage culture procedure has been developed for highly efficient shoot regeneration from leaf and internode explants of Bacopa monnieri. Adventitious shoot buds were obtained on the shoot induction medium containing Murashige and Skoog’s (MS) basal salt supplemented with 1.5 mg/l thidiazuron and 0.5 mg/l naphthalene acetic acid; these shoot buds were subcultured on the multiplication (second) medium amended with BAP (benzyl amino purine). Multiplication medium containing 0.5 mg/l BAP produced more shoots (135) and longer shoots (7.8 cm) with more nodes (6). Best response of root induction with more number of roots (16.5) and longer roots (8.7 cm) was observed in half strength MS basal medium supplemented with 1.0 mg/l IBA (indole-3-butyric acid) and 0.5 mg/l phloroglucinol. In vitro obtained plants were transferred to the field after hardening with a 100% survival rate. Random amplified polymorphic DNA analysis was carried out using five random primers. The amplification products were monomorphic in micropropagated plants and similar to those of mother plant. No polymorphism was detected revealing the genetic integrity of micropropagated plants.     

Complex genetic association of 6q23 with autoimmune rheumatic conditions

Autoantibodies to the polymyositis/scleroderma (PM/Scl) complex have been associated with systemic sclerosis and PM/Scl overlap syndrome. The report of Hanke and colleagues in a recent issue of Arthritis Research and Therapy is the first to describe the separate evaluation of anti-PM/Scl-75c and PM/Scl-100 autoantibodies and their relationship to clinical manifestations of systemic sclerosis. Several observations are of paramount interest, but are not in general agreement with earlier studies. These include the prevalence of anti-PM/Scl antibodies in systemic sclerosis, the association with certain clinical manifestations and prognosis of patients. This report will hopefully trigger systematic multi-centre studies to confirm and/or elucidate the novel line immunoassay and clinical associations.     

A Computational Model for the Loss of Neuronal Organization in Microcolumns

A population of neurons in the cerebral cortex of humans and other mammals organize themselves into vertical microcolumns perpendicular to the pial surface. Anatomical changes to these microcolumns have been correlated with neurological diseases and normal aging; in particular, in area 46 of the rhesus monkey brain, the strength of microcolumns was shown to decrease with age. These changes can be caused by alterations in the spatial distribution of the neurons in microcolumns and/or neuronal loss. Using a three-dimensional computational model of neuronal arrangements derived from thin tissue sections and validated in brain tissue from rhesus monkeys, we show that neuronal loss is inconsistent with the findings in aged individuals. In contrast, a model of simple random neuronal displacements, constrained in magnitude by restorative harmonic forces, is consistent with observed changes and provides mechanistic insights into the age-induced loss of microcolumnar structure. Connection of the model to normal aging and disease are discussed.     

Validation of Next Generation Sequencing Technologies in Comparison to Current Diagnostic Gold Standards for BRAF,EGFR and KRAS Mutational Analysis

Next Generation Sequencing (NGS) has the potential of becoming an important tool in clinical diagnosis and therapeutic decision-making in oncology owing to its enhanced sensitivity in DNA mutation detection, fast-turnaround of samples in comparison to current gold standard methods and the potential to sequence a large number of cancer-driving genes at the one time. We aim to test the diagnostic accuracy of current NGS technology in the analysis of mutations that represent current standard-of-care, and its reliability to generate concomitant information on other key genes in human oncogenesis. Thirteen clinical samples (8 lung adenocarcinomas, 3 colon carcinomas and 2 malignant melanomas) already genotyped for EGFR, KRAS and BRAF mutations by current standard-of-care methods (Sanger Sequencing and q-PCR), were analysed for detection of mutations in the same three genes using two NGS platforms and an additional 43 genes with one of these platforms. The results were analysed using closed platform-specific proprietary bioinformatics software as well as open third party applications. Our results indicate that the existing format of the NGS technology performed well in detecting the clinically relevant mutations stated above but may not be reliable for a broader unsupervised analysis of the wider genome in its current design. Our study represents a diagnostically lead validation of the major strengths and weaknesses of this technology before consideration for diagnostic use.     

Surgical Technique for the Implantation of Tissue Engineered Vascular Grafts and Subsequent In Vivo Monitoring

The development of Tissue Engineered Vessels (TEVs) is advanced by the ability to routinely and effectively implant TEVs (4-5 mm in diameter) into a large animal model. A step by-step protocol for inter-positional placement of the TEV and real-time digital assessment of the TEV and native carotid arteries is described here. In vivo monitoring is made possible by the implantation of flow probes, catheters and ultrasonic crystals (capable of recording dynamic diameter changes of implanted TEVs and native carotid arteries) at the time of surgery. Once implanted, researchers can calculate arterial blood flow patterns, invasive blood pressure and artery diameter yielding parameters such as pulse wave velocity, augmentation index, pulse pressures and compliance. Data acquisition is accomplished using a single computer program for analysis throughout the duration of the experiment. Such invaluable data provides insight into TEV matrix remodeling, its resemblance to native/sham controls and overall TEV performance in vivo.