Multi-domain cognitive screening test for neuropsychological assessment for cognitive decline in acclimatized lowlanders staying at high altitude.

Background & objectives: Ascent to high altitude has been reported to cause hippocampal atrophy and cognitive impairment in mountaineers. We assessed the cognitive performance and probable occurrence of mild cognitive impairment (MCI) in acclimatized lowlanders (ALL) staying at altitudes above 4,300 m for duration above 12 months and validated a multi-domain cognitive screening test (MDCST) for future demographic studies on MCI. Methods: Following evaluation of sensitivity and correlation of the newly developed MDCST battery with Mini Mental State Examination (MMSE) and Clinical Dementia Rating (CDR) scores on a group of 28 individuals, the MDCST battery was validated on a population of 843 ALL staying at high altitude MSL >4,300 m and 862 subjects staying at MSL <230 m. EEG recordings were performed on 840 ALL staying at altitudes above 4,300 m and 743 control subjects staying at MSL <230 m. Results: Percentage prevalence of MCI was 4.18 per cent in the ALL population as assessed by MMSE while that of the LL population was <0.42 per cent. The percentage prevalence of MCI based on calculations from the MDCST scores was 12.4 per cent in the ALL population as compared to 1.19 per cent in the LL population. Decrease in alpha wave amplitude at the T3 and T4 sources in MCI subjects was observed in LL group while there was an increase in amplitude for alpha wave in these regions in the ALL groups. Domain specific MDCST showed decline in immediate recall, procedural memory and mind body co-ordination which was negligible in the LL population. Interpretation & conclusions: MDCST exhibited excellent psychometric properties in terms of sensitivity, and test-retest reliability qualifying it to be used as a more effective cognitive measure for assessment of MCI in demographic studies in comparison to traditional measures. Our findings also showed increased prevalence of MCI in ALL population staying for longer durations at high altitude which is neurophysiologically distinct from MCI leading to Alzheimer's disease.

Amelioration of inflammatory responses by Chlorogenic acid via suppression of pro-inflammatory mediators.

The premise of the present investigation was to evaluate the detailed anti-inflammatory properties of chlorogenic acid (CGA) and to delineate the possible mode of action. To explore the anti-inflammatory profile, we evaluated the effect of CGA on TNF-alpha expression (in vitro); carrageenan induced rat paw edema and carrageenan induce pleurisy (in vivo). In our studies, CGA significantly inhibited the TNF-alpha expression, paw edema and antioxidant enzymes in livers of rats in pre-treatment schedule but failed to exert any effect when administered 1 h after carrageenan injection. CGA was also found to be safe, as confirmed by the results of acute toxicity studies and MTT assay. CGA also caused reduction in total leucocytes count most probably by inhibiting neutrophils, but could not alter mononuclear cells count in carrageenan induced pleurisy. Inhibition of exudation was evidenced by the less exudate formation in CGA treated animals, which may be due to decrease in vascular permeability which was further confirmed in acetic acid induced vascular permeability model in mice where significant decrease in vascular permeability was observed. CGA was highly effective in reducing the arachidonic acid metabolites, nitric oxide and pro-inflammatory cytokines production in a dose dependent manner and in some conditions effect observed was almost comparable to ibuprofen. Result of the present investigation shows the anti-inflammatory effects of CGS in different models.

Detection of fetal malnutrition using “CAN score”.

Objective. Use of clinical assessment of nutrition status (CAN) score to assess the prevalence of fetal malnutrition among term newborns and to compare other anthropometric criteria used to assess fetal growth. Methods. Prospective study of 529 term healthy newborns assessed using CAN score .Complete anthropometric assessment and determination of weight for gestation was done. Using CAN score as a standard, the usefulness of birth weight, weight for gestation, length, head circumference (HC), mid arm circumference (MAC), MAC/HC ratio and Ponderal index to assess fetal nutrition was determined. Results. With a cut off value of 25, CAN score identified 148 (27.97%) malnourished neonates. 4% of appropriate for gestational age neonate were malnourished and 42.9 % of small for gestational age neonates were well nourished. When CAN score was taken as a standard, weight for gestation and MAC/HC had the highest sensitivity to identify malnourished neonates (92.5% & 90.5%). Conclusion. CAN score identifies malnourished neonates which can be missed by other methods and identifies well nourished neonates classified as growth retarded by other methods.

Egg-laying rhythm in Drosophila melanogaster.

Extensive research has been carried out to understand how circadian clocks regulate various physiological processes in organisms. The discovery of clock genes and the molecular clockwork has helped researchers to understand the possible role of these genes in regulating various metabolic processes. In Drosophila melanogaster, many studies have shown that the basic architecture of circadian clocks is multi-oscillatory. In nature, different neuronal subgroups in the brain of D. melanogaster have been demonstrated to control different circadian behavioural rhythms or different aspects of the same circadian rhythm. Among the circadian phenomena that have been studied so far in Drosophila, the egg-laying rhythm is unique, and relatively less explored. Unlike most other circadian rhythms, the egg-laying rhythm is rhythmic under constant light conditions, and the endogenous or free-running period of the rhythm is greater than those of most other rhythms. Although the clock genes and neurons required for the persistence of adult emergence and activity/rest rhythms have been studied extensively, those underlying the circadian egg-laying rhythm still remain largely unknown. In this review, we discuss our current understanding of the circadian egg-laying rhythm in D. melanogaster, and the possible molecular and physiological mechanisms that control the rhythmic output of the egg-laying process.

Circadian clocks and life-history related traits: is pupation height affected by circadian organization in Drosophila melanogaster?

In D. melanogaster, the observation of greater pupation height under constant darkness than under constant light has been explained by the hypothesis that light has an inhibitory effect on larval wandering behaviour, preventing larvae from crawling higher up the walls of culture vials prior to pupation. If this is the only role of light in affecting pupation height, then various light : dark regimes would be predicted to yield pupation heights intermediate between those seen in constant light and constant darkness. We tested this hypothesis by measuring pupation height under various light : dark regimes in four laboratory populations of Drosophila melanogaster. Pupation height was the greatest in constant darkness, intermediate in constant light, and the least in a light/dark regime of LD 14:14 h. The results clearly suggest that there is more to light regime effects on pupation height than mere behavioural inhibition of wandering larvae, and that circadian organization may play some role in determining pupation height, although the details of this role are not yet clear. We briefly discuss these results in the context of the possible involvement of circadian clocks in life-history evolution.