The distribution of SMN protein complex in human fetal tissues and its alteration in spinal muscular atrophy

Spinal muscular atrophy (SMA) is a common autosomal recessive neuromuscular disorder characterized by degeneration of motor neurons of the spinal cord and muscular atrophy. SMA is caused by alterations to the survival of motor neuron (SMN) gene, the function of which has hitherto been unclear. Here, we present immunoblot analyses showing that normal SMN protein expression undergoes a marked decay in the postnatal period compared with fetal development. Morphological and immunohistochemical analyses of the SMN protein in human fetal tissues showed a general distribution in the cytoplasm, except in muscle cells, where SMN protein was immunolocalized to large cytoplasmic dot-like structures and was tightly associated with membrane-free heavy sedimenting complexes. These cytoplasmic structures were similar in size to gem. The SMN protein was markedly deficient in tissues derived from type I SMA fetuses, including skeletal muscles and, as previously shown, spinal cord. While our data do not help decide whether SMA results from impaired SMN expression in spinal cord, skeletal muscle or both, they suggest a requirement for SMN protein during embryo-fetal development.      

External validation of prognostic models for ongoing pregnancy after in- vitro fertilization

This study aimed to validate prognostic models for predicting ongoing pregnancy after the first and second in-vitro fertilization cycles. Models were developed using data from the University Hospital, Nijmegen, 1991-1994 and tested using more recent data from the same centre and data from two other centres. Although the variables included in the models seemed plausible, the predictions of the models were unsatisfactory. The models did not discriminate between women who had achieved pregnancy and women who did not achieve pregnancy; neither could they indicate which women had a (very) low probability of ongoing pregnancy. Taking into account the success rate of a specific clinic or the success rate during a specific period did not show any advantage. The predictions were even inaccurate in the same hospital during another period. It is obvious that these prognostic models should not be used. This study shows the importance of validating prognostic models before their implementation in clinical practice.      

ESTIMATES OF EX-SERVICEMEN POPULATION FOR NEXT 30 YEARS: A NEED TO REORIENT OUR HEALTH PLANNING

A mathematical model, using survival analysis methods has been developed to estimate the total population as well as the populations as per specific age groups of ex-servicemen for the next 30 years. The results indicate that from the present population of 13.75 lakhs., the total population of ex-servicemen would be 15.62 lakhs by 2027 A.D. In addition, there are likely to be noteworthy changes in the population structure. While the population of geriatric age group (65 years and above) is only 21% at present compared to 49% from age group 45-54 years, by 2027 A.D. the geriatric age group would contribute to 34% of the ex-servicemen population while 45-54 years age group would constitute only 36%. There is a need, therefore, to start rethinking on our future plans as regards health services since geriatric health problems are likely to become a leading health issue after the next ten years.KEY WORDS: Ageing population, Demography, Epidemiological models, Health care planning     

CAN WAIST/HIP RATIO BE USED AS A SIMPLE MEASURE OF CARDIOVASCULAR RISK IN THE ARMED FORCES : RESULTS FROM A FIELD EPIDEMIOLOGICAL STUDY

A cross-sectional analytical epidemiologic study was undertaken in the community setting, on 1080 army personnel in a field formation, to study the association between waist/hip ratio (WHR) and certain physiological and biochemical parameters of cardiovascular risk. The study revealed that Junior Commissioned Officers, personnel aged 35 years and above, and personnel from Services had an increased probability of having higher WHR. WHR was consistently, linearly and significantly associated with increasing mean values of serum cholesterol, blood sugar and blood pressure. The optimum cut-off point of WHR from the findings of this study seems to be 0.91 and above. Beyond this value of WHR, the cardiovascular risk increases significantly and becomes more dramatic at WHR values of 0.96 and above.KEYWORDS: Cardio-vascular risk, Central adiposity, Obesity, Waist/hip ratio     

Robust estimation of interconnected systems subject to sensor nonlinearities

An efficient robust LMI‐based scheme is developed for decentralized state‐estimation of linear interconnected systems with static nonlinear interconnections and subjected to sensor nonlinearities. The interconnections satisfy quadratic constraints with manipulated parameters and the sensor nonlinearities are modeled as sector nonlinearities. The design procedure utilizes a general linear estimator structure and consists of two steps: the first giving a block‐diagonal Lyapunov matrix together with the robustness degree and the second determining the filter parameters. A numerical example is provided to illustrate the applicability of the method. Copyright © 2012 John Wiley & Sons, Ltd.     

Effects of Tobacco Smoking on the Dorsum of the Tongue and Buccal Epithelium

Objective: The aim of this study was to assess the effects of tobacco smoking on the dorsum of the tongue and buccal epithelium. Methodology: This case control cross-sectional study was conducted with 174 smoking and non-smoking volunteers living in the city of Hail, Northern KSA. Cytological Materials were obtained from buccal mucosa and dorsum of the tongue, and assessed using cytopathological methods. Results: In buccal smears, cytological atypia was observed in 17 out of 101 (16.8%) smoker cases but only 3/73(4.1%) of the controls. For cytological atypia in buccal and tongue smears, the adjusted odd ratio (OR) and the 95% confidence interval (CI) were found to be 4.7 (1.3-16.8), P < 0.016)) and 4.3 (0.93- 20.2), P <0.06)), respectively, in the two sites. Conclusion: Tobacco smoking is a major risk factor for occurrence of cytological atypia, which might subsequently develop into oral precancerous and cancerous lesions. Oral exfoliative cytology is an easy and cheap non-invasive procedure which appears highly suitable for screening populations at risk of developing oral cancer.