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Background: To explore the association of sleep timings, duration, consistency, and chronotype with premyopia and myopia among Indian children., Methods: This hospital-based cross-sectional study included 453 children, aged 6-12 years. Two myopia participants were selected for each individual with the corresponding premyopia or emmetropia. All children underwent cycloplegic autorefraction and ocular biometric tests. The Children's Sleep Habits Questionnaire (CSHQ) and parental information on behavioral habits were used to assess the association of sleep parameters with myopia and premyopia using logistic regression models., Results: Both myopia and premyopia exhibited significant late bedtime, short sleep duration, early wakeup time on only weekdays, and longer weekend catch-up sleep than emmetropia children (p < 0.05). In multivariate analysis, late bedtime (more than 24:00 a.m.) on weekdays (Odds ratio, OR = 3.63, 95% CI [0.74, 8.68]) as well as on free days (OR = 1.04, 95% CI [0.02, 8.08]); and early wake-up time only on weekdays (5:00-6:00 a.m., OR = 2.16, 95% CI [0.24, 6.76] and 06:00-07:00 a.m., OR = 2.42, 95% CI [0.51, 8.44]) were associated with increased risk of myopia (all p < 0.05) but not premyopia. After adjusting the confounding factors, when each of the eight CSHQ subscale components was analyzed, only bedtime resistance, night waking, and daytime sleepiness scores were significantly associated with a higher risk for premyopia and myopia (p < 0.05)., Conclusions: The sleep quality components, including bedtime resistance, night waking, and daytime sleepiness, equally involve a higher risk for myopia as well as premyopia., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The circadian variation in stroke occurrence is a well-documented phenomenon. However, the circadian effect on stroke outcome, particularly on post-stroke cognition, has not yet been fully elucidated. We aim to evaluate the influence of diurnal variation of stroke onset upon post-stroke cognition and development of post-stroke depression. Based on 4-hourly time period of stroke occurrence, 249 recruited cohorts were categorized into 6 groups. Several clinical and cognitive parameters were compared among the groups. Then, the mRNA expression of core clock genes in Peripheral Blood Mononuclear Cells were quantified and correlated with post-stroke outcomes among 24 acute phase cases with day-time or night-time stroke occurrence. Furthermore, the genetic susceptibility towards a higher number of cases in the morning was examined by genotyping CLOCK (rs1801260T/C, rs4580704G/C) and CRY2 (rs2292912C/G) genes variants in cases and 292 controls. In our study, the peak for highest incidence although observed during the early morning from 4 to 8 am, the nocturnal-onset stroke cases showed more severity (12.2 ± 5.67) at the time of admission irrespective of arterial territory involved. The night onset cases were also found to be more susceptible to develop language impairment and post-stroke depression in due course of time. Upon transcript analysis, circadian genes (BMAL1 and CRY1) were found to be downregulated in night-time cases than day-time ones during the acute phase of onset. In addition, those mRNA levels also showed a correlation with raw scores for language and depression. However, the difference in incidence frequency along a day did not reveal any genetic correlation. Therefore, we suggest night-time stroke to be positively associated with higher immediate severity and poor cognitive outcome than day-time injury and propose downregulation of circadian genes during the acute phase could be the underlying molecular mechanism for this., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

In humans, sleep is an essential physiological process for life and survival. The main objective of the current study is to determine the behavioural sleep patterns and social jetlag in elderly adults. The second objective is to define the relationship among subjective sleep quality, mid-sleep timings, social jetlag, and sunlight exposure. We recruited 945 female and 1047 male participants aged ≥ 60 years from 65 rural villages in the Sambalpur district of Odisha, India. The Munich Chrono Type Questionnaire (MCTQ) is a self-reported questionnaire that measures a person's behavioral sleep variables, including social jetlag and chronotype, whereas the Pittsburgh Sleep Quality Index (PSQI) measures the subjective sleep quality of an individual. We employed MCTQ and PSQI to obtain behavioral sleep variables and subjective sleep quality in the recruited subjects. The behavioral sleep variables were compared using a paired t -test on both work and work-free days. In addition, the behavioral sleep variables as a function of gender were compared using an independent Student's t -test. In the current study, most of the elderly individuals reported both midpoint of sleep on workdays (MSW) and midpoint of sleep on work-free days (MSF) between 00:01-03:00. The averages of mid-sleep timings between workdays and work-free days were not statistically significant. Data on MSFsc (midpoint of sleep on work-free days sleep corrected) indicated that most elderly adults (99.6%) are morning type; they go to bed early and wake up early. The elderly participants from the rural population of Sambalpur district in western Odisha had the least social jetlag and exhibited good subjective sleep quality. It would be worthwhile to find out the determinants of these positive features apropos social jetlag and behavioural sleep patterns.

It is not well understood how the spectral composition (wavelength) of daylight that varies considerably during the day and seasons affects photoperiodic responses in a seasonal species. Here, we investigated the molecular underpinnings of wavelength-dependent photoperiodic induction in migratory redheaded buntings transferred to 13 h long days in neutral (white), 460 nm (blue), 500 nm (green) or 620 nm (red) wavelength that were compared with one another, and to short day controls for indices of the migratory (body fattening and weight gain, and Zugunruhe) and reproductive (testicular maturation) responses. Buntings showed wavelength-dependent photoperiodic response, with delayed Zugunruhe and slower testis maturation under 620 nm red light. Post-mortem comparison of gene expressions further revealed wavelength-dependence of the photoperiodic molecular response. Whereas there were higher retinal expressions of opn2 (rhodopsin) and opn5 (neuropsin) genes in red daylight, and of rhodopsin-like opsin (rh2) gene in green daylight, the hypothalamic opn2 mRNA levels were higher in blue daylight. Similarly, we found in birds under blue daylight an increased hypothalamic expression of genes involved in the photoperiodic induction (thyroid stimulating hormone subunit beta, tshb; eye absent 3, eya3; deiodinase type 2, dio2) and associated neural responses such as the calcium signaling (ATPase sarcoplasmic/endoplasmic reticulum Ca2+ transporting 2, atp2a2), dopamine biosynthesis (tyrosine hydroxylase, th) and neurogenesis (brain-derived neurotrophic factor, bdnf). These results demonstrate transcriptional changes in parallel to responses associated with migration and reproduction in buntings, and suggest a role of daylight spectrum in photoperiodic induction of the vernal response in obligate spring avian migrants., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Population pharmacokinetic/pharmacodynamic (PK/PD) analysis was performed for extensive data for differing dosage forms and routes for dexamethasone (DEX) and betamethasone (BET) in 48 healthy nonpregnant Indian women in a partial and complex cross-over design. Single doses of 6 mg dexamethasone phosphate (DEX-P), betamethasone phosphate (BET-P), or 1:1 mixture of betamethasone phosphate and acetate (BET-PA) were administered orally (PO) or intramuscularly (IM) where each woman enrolled in a two-period cross-over study. Plasma concentrations collected over 96 h were described with a two-compartment model with differing PO and IM first-order absorption inputs. Overall, BET exhibited slower clearance, similar volume of distribution, faster absorption, and longer persistence than DEX with BET acetate producing extremely slow absorption but full bioavailability of BET. Six biomarkers were assessed over a 24-h baseline period with four showing circadian rhythms with complex baselines. These baselines and the strong responses seen after drug dosing were fitted with various indirect response models using the Laplace estimation methods in NONMEM 7.4. Both the PK and six biomarker responses were well-described with modest variability likely due to the homogeneous ages, weights, and ethnicities of the women. The drugs either inhibited or stimulated the influx processes with some models requiring joint inclusion of drug effects on circadian cortisol suppression. The biomarkers and order of sensitivity (lowest IC 50 /SC 50 to highest) were: cortisol, T-helper cells, basophils, glucose, neutrophils, and T-cytotoxic cells. DEX sensitivities were generally greater than BET with corresponding mean ratios for these biomarkers of 2.86, 1.27, 1.72, 1.27, 2.69, and 1.06. Overall, the longer PK (e.g. half-life) of BET, but lesser PD activity (e.g. higher IC 50 ), produces single-dose response profiles that appear quite similar, except for the extended effects from BET-PA. This comprehensive population modeling effort provides the first detailed comparison of the PK profiles and six biomarker responses of five commonly used dosage forms of DEX and BET in healthy women.

COVID-19 has brought the world into uncharted waters. Many countries are under lockdown, the economy has ground to a halt, and almost everyone is afraid of dire consequences. The unprecedented changes that came on so quickly due to the pandemic and stay-at-home confinement to accomplish social distancing and mitigate risk for infection pose many challenges. These include compromised health, well-being, and sleep as a consequence of disruption of the daily life routine, anxiety, worry, isolation, greater family and work stress, and excessive screen time. Our study of 203 corporate sector professionals performing '9-5' work from home during this phase of the pandemic and of 325 undergraduate and postgraduate university students substantiates, relative to the before lockdown condition, more extensive feelings of sleepiness, with significantly ( p < .05) increased daytime nap duration, and depressive symptomatology ( p < .001) that is a matter of concern. Moreover, the chronic stress of living through a pandemic led to a host of physical symptoms, like headaches, insomnia, digestive problems, hormonal imbalances, and fatigue.

A lifestyle with erratic eating patterns and habits predisposes youngsters to obesity. Through a two-phase feasibility study among Indian students living in the Delhi area, we longitudinally examined the following: (1) the daily eating-fasting cycles of students (N = 34) in school and college using smartphones as they transition from high school (aged 13-15 years; nIX = 13) to higher secondary school (HSSS; 16-18 years; nXII = 9) to their first year (FY) of college (18-19 years; nFC = 12); and (2) daily activity-rest cycles and light-dark exposure of 31 higher secondary school students (HSSS) using actigraphy. In phase 1, students' food data were analyzed for temporal details of eating events and observable differences in diet composition, such as an energy-dense diet (fast food (FF)), as confounding factors of circadian health. Overall, the mean eating duration in high school, higher secondary and FY college students ranged from 14.1 to 16.2h. HSSS exhibited the shortest night fasting. Although FY college students exhibited the highest fast food percentage (FF%), a positive correlation between body mass index (BMI) and FF% was observed only among HSSS. Furthermore, the body weight of HSSS was significantly higher, indicating that FF, untimely eating and reduced night fasting were important obesity-associated factors in adolescents. Reduced night fasting duration was also related to shorter sleep in HSSS. Therefore, food data were supplemented with wrist actigraphy, i.e., activity-rest data, in HSSS. Actigraphy externally validated the increased obesogenic consequences of deregulated eating rhythms in HSSS. CamNtech motion watches were used to assess the relationship between disturbed activity cycles of HSSS and other circadian clock-related rhythms, such as sleep. Less than 50% of Indian HSSS slept 6 hours or more per night. Seven of 31 students remained awake throughout the night, during which they had more than 20% of their daily light exposure. Three nonparametric circadian rhythm analysis (NPCRA) variables revealed circadian disruption of activity in HSSS. The present study suggests that inappropriate timing and quality of food and sleep disturbances are important determinants of circadian disruptions in adolescents attending school., Competing Interests: The authors have declared that no competing interests exist

This is the first research article that documents circadian variability in behavioral variables, namely resting (Rt) and standing (St) in stray street dogs of Sambalpur city, India. We also estimated the abundance as a function of time of the day and gender in a population of stray dog inhabiting streets of the city. In addition, we determined the association between the behavioral variables and the environmental variables, such as light intensity, sound intensity, temperature and humidity. We determined the abundance of street dogs at 10 hotspots using the photographic capture-recapture technique and Lincoln index equation. In another study, we determined dogs' density along the three randomly selected routes that connect the beginning (Dhanupali) and end (P.C. Bridge) of the city precincts. We recorded the resting and standing activities of the stray street dogs using still and video cameras at four times of the day continuously over a longitudinal timescale of 72 hours. This study was conducted at four randomly selected dog hotspots. Subjecting the log-transformed time series data to the Cosinor rhythmometry we obtained three different rhythm parameters, such as mesor (M), amplitude (A) and acrophase (Ø) of the rhythm in resting and standing behavior of stray street dogs. We found out both spatial and temporal variability in the behavior of street dogs. The sightings of dogs were always more during the evening and nighttime irrespective of the investigated routes and hotspots. Further, we also observed that the abundance of male dogs was always significantly more as compared with the bitches. A lack of association between two attributes the time of the day and gender apropos the number of sightings of the street dogs was validated by the Fisher's exact test. Using Pearson's correlation analysis technique we found a negative relationship between light intensity and resting activity. In addition, we also found a negative association between standing activity and ambient environmental temperature. These findings were complimentary to the observed circadian variability in the resting and standing behavior of the stray street dogs. In conclusion, despite a few limitations, this study documents a statistically significant circadian rhythm in activities of stray street dogs. It also highlights spatial variability in the abundance of dogs on the streets and hotspot localities of the urban Sambalpur. We do have a hunch. It is likely that similar phenomenamight be of common occurrence in many urban areas of the world. These data might also help in addressing street dog menace - one of the major problems the people and administrative authorities of most of the Indian cities and elsewhere worldwide are experiencing since quite long.

Background: India is a subtropical country with clear seasonal variations in weather conditions. Seasonal and circadian variation in occurrence of subtypes of cerebrovascular disease has been of interest in several studies from different countries and climate zones, but discrepant results have made the conclusions unclear. The aim of the present study was to observe the seasonal and circadian variation in the occurrence of stroke and its subtypes among our population., Methods: This was a cross-sectional observational study based on new cases and past cases of stroke on follow-up, conducted between January 2011 and December 2012 in the Department of Neurology, at the All India Institute of Medical Sciences, New Delhi, India. The date and time of onset of the stroke was recorded. The categorization of months into season was in accordance with the Indian Meteorological Department guidelines. The time of onset was distributed into 6 hourly intervals. Statistical calculations were performed using Stata version 12.1 and SPSS version 20., Results: A total of 583 patients were included for the study. The rate of occurrence of stroke was highest in the late morning 0600-1159 hours (P value <.001) compared with other times of the day, regardless of gender or age for both ischemic and hemorrhagic strokes. It was lowest in late evening (1800-2359 hours) quadrant compared with other quadrants. Although there was no significant difference found by dichotomizing the groups into two 6-month periods, there was an increasing trend in number of patients with stroke during the months November-February. There was no difference in stroke occurrence between the types of stroke or within each type among different seasons with different temperatures. Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification of ischemic strokes also did not show any association with season or circadian rhythm., Conclusions: There is a significant increase in occurrence of strokes between 0600 and 1159 hours and lowest between 1800-2359 hours. No significant variation in stroke occurrence or subtype for any of the seasons was observed., (Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.)

The Healthy Eating Asians Remain Together (HEART) study was carried out to investigate the relationship between 24-hour urine nutritional biomarkers and cardiometabolic risks in India. A total of 168 participants underwent health examination to assess body mass index, blood pressure, and 24-hour urine samples. The participants were divided into normotensive and hypertensive. The average blood pressure, weight, and body mass index were significantly high in patients considered to be hypertensive, and 24-hour urine biomarkers showed significant differences in sodium and magnesium/creatinine ratios in patients aged 40 and older. High sodium intake and reduction in magnesium consumption are associated with increased blood pressure in patients from India., (©2014 Wiley Periodicals, Inc.)

Family is the smallest unit of people to share most of the lifestyle, environmental and genetic factors. They are likely to have similarity in many physiological and behavioural aspects. Therefore, we designed a protocol to test the effect of large rural Indian families living together (Kumbas), on blood pressure variability. We also investigated the hypothesis that 'nocturnal dipping' in systolic blood pressure (SBP) is not heritable. Members of two families (1 and 2) consisting of 3-4 generations willingly participated in the study. Both families (natives of Chhattisgarh) belong to reasonably peaceful rural area and are financially stable. Farming is the main occupation of the members of both families. Few members of the families had jobs or small business. The null hypothesis regarding heritability of nocturnal dipping trait was accepted based on data emanating from either of the studied families. Hourly-averaged values depicted less variation in males and females of family 1 from midnight to early morning at around 06:00, as compared to that in males and females of family 2. The 24 h averages of BP in family 2 were significantly higher as compared to that in family 1. Further, in family 2 the peaks of SBP, diastolic blood pressure (DBP) and mean arterial pressure (MAP) occurred significantly earlier as compared to that in family 1. The peak spread of SBP, DBP, heart rate (HR), MAP and pulse pressure (PP) among the members of family 1 was narrower than that for the members of family 2. Arbitrary cut-off values for classification of dipping, small sample size, and age dependency of nocturnal dipping might have marred outcome of the pedigree analysis of nocturnal dipping trait in this study. We have a hunch that the family shares typical temporal ups and downs in 24 h BP and HR. The above hypothesis needs confirmation based on studies with large data set involving subjective and objective assessment of the effects of psychosocial factors on BP and HR variability.

Background: Several pen and paper measures of human circadian preference are available in English, but none are available in Hindi, hampering research in circadian behavior among Hindi speaking populations in India and elsewhere. The present study describes a Hindi version of the Composite Scale of Morningness (CSM), a self-reported questionnaire widely used to assess morningness/eveningness (M/E). M/E has been used a proxy for circadian phase in lieu of cumbersome and expensive laboratory studies., Method: The thirteen item English version of the CSM was translated into Hindi and independently back translated into English. Inconsistencies between the original and back translated versions were then resolved. Both versions were next administered to bilingual persons at Delhi, India (N=130). After intra-class correlations between the Hindi and the English versions were examined, the Hindi version was administered to community based participants representing different age groups (N=310)., Results: There was satisfactory intra-class correlation (ICC) between the total scores for the Hindi and the English versions of the CSM (Cronbach's alpha=0.873), with variation for individual items scores. Total CSM scores in the second sample suggested a significant association with age, consistent with published reports with the English CSM, i.e., morningness tendencies were more likely to be reported by older adults. Significant associations with gender or educational status were not observed., Conclusions: The Hindi CSM is a brief questionnaire that provides behavioral measures of diurnal preference. It is freely available for research in Hindi speaking populations., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The gravitational pull of the moon on the earth is not the same in all phases of the lunar month, i.e. new moon (NM), first quarter (FQ), full moon (FM) and third quarter (TQ), and as a result the amplitude of tide differs in different phases. The gravitational pull of the moon may have effects on the fluid compartments of the human body and hence the cardiovascular system may be affected differentially in the different phases of the lunar month. In the present study resting heart rate (HR) and blood pressure (BP), physical fitness index (PFI), peak HR and BP immediately after step test, and recovery HR and BP after step test were measured during different phases of the lunar month in 76 male university students (age 23.7 ± 1.7 years). At rest, both systolic and mean arterial BP were ∼5 mmHg lower in NM and FM compared to FQ and TQ, but resting HR was not significantly different between phases. Further, peak HR and peak systolic BP after step test were lower (∼4 beat/min and ∼5 mmHg, respectively) in NM and FM compared to FQ and TQ. PFI was also higher (∼5) in NM and FM compared to FQ and TQ. Recovery of HR after step test was quicker in NM and FM compared to that of FQ and TQ. It appears from this study that gravitational pull of the moon may affect the cardiovascular functions of the human body. Moreover, the physical efficiency of humans is increased in NM and FM due to these altered cardiovascular regulations.

Delirium is understudied in developing countries, where there tends to be a lower proportion of older persons and comorbid dementia. The authors assessed 100 consecutive cases of DSM-IV delirium (patients' mean age: 44.4 [standard deviation: 19.4] years; mean DRS-R98 score: 25.6 [3.6]) referred to an adult Consultation-Liaison Psychiatry service in Northern India. Disturbances of attention, orientation, visuospatial ability, and sleep disturbance were the most frequent symptoms, followed by language, thought-process abnormality, and motor agitation. A three-factor solution was identified, representing domains for cognition, higher-order thinking, and circadian rhythm/psychosis. These domains can guide studies addressing the relationship between symptom profile, therapeutic needs, and outcomes and are consistent with core domains previously identified in other countries.

Rising early in the morning has been a prescribed discipline of ancient Indian tradition. While there are no scientific studies comparing early rising volitionally versus circumstantially, selected studies on the latter (rising forcefully) have shown negative impact on an individual's peroformance. Hence the present study was undertaken to assess the influence of early rising (during Brahma-muhurtha) on tasks requiring attention and the ability to recall. Fifty four normal healthy male volunteers, with ages ranging from 16-22 years from a residential school were selected. They were randomly allocated to two groups (Brahma-muhurtha and control). They were assessed on day 1, day 10 and day 20 of the intervention, using a digit letter substitution task and verbal and spatial memory task. The Brahma-muhurtha group were asked to rise before 4:30 am in the morning based on the traditional Indian astrological calculations, while the control group were allowed to wake up just before 7 am which was their regular timing for waking. Brahma-muhurtha group after 20 days showed a significant improvement in the net scores for digit letter substitution task as well as scores for verbal and spatial memory tasks. The control group also showed an improvement in the memory task but not in the task requiring attentional processes. The present study suggests that rising early in the morning as described in ancient Indian tradition influences the process of attention and can improve the ability to recall.

Narcolepsy is a common sleep disorder with a prevalence of about 0.02%. However, it may remain largely unrecognized in the Indian population owing to the perceived low prevalence. To the best of our knowledge there is only one case of narcolepsy reported from India so far. We present a case of narcolepsy with cataplexy with classical clinical and polysomnographic findings of narcolepsy.

Peak expiratory flow rate (PEFR) variability follows a specific pattern in asthmatics as well as in healthy individuals. There is scarcity of data for Indian healthy subjects. The PEFR (L/min.) was measured with Wright's portable peak flow meter at 05:00, 8:00, 11:00, 14:00, 17:00, 20:00 and 23:00 hours in 42 healthy, non-smoking adults of age group between 18-26 years. The variability of PEFR revealed a circadian pattern. PEFR levels tend to increase from morning at 5:00 hours till evening at 17:00 hours, with peak PEFR in evening at 17:00 hours, after which there was a progressive fall in PEFR levels, till morning 5:00 hours. This study provides the preliminary reference data of circadian pattern of PEFR in healthy individuals.

An internal 24-hour biological clock working in tandem with external environmental cues like bright light regulates our daily rhythms specially sleep-wake cycle. In a blind individual, due to absence of external cue endogenous rhythm may take upper hand and free running of sleep-wake cycle starts without any synchronicity with day-night cycle, creating ground for sleep disorders. To evaluate the frequency of sleep disorders, 65 blind individuals without any comorbid medical or surgical problem were interviewed according to the criteria of Diagnostic and Statistical Manual of Mental Disorder-IV (DSM-IV). Simultaneously 70 persons with no visual impairment were assessed in the same manner as used for blind persons. Blind patients showed far higher presence (44.6%) of sleep problems compared to controls (15.7%), and this difference was highly significant statistically [odd's ratio (OR) = 4.32, CI 95 =1.8-10.54]. Blind patients showed far higher presence (43.1%) of DSM-IV based diagnosis compared to controls (8.6%), and this difference was highly significant statistically [OR = 8.072, CI 95 = 3.059-21.298]. Circadian sleep disorders, insomnia and hypersomnia were relatively higher in blind patients. High incidence of sleep disorders calls for development of short reliable screener for sleep disorders among blind persons and better liaison among ophthalmologists and psychiatrists for early detection of this problem.

This paper examines the importance of vision in the lives of nocturnal primates in comparison to diurnal and cathemeral species. Vision is the major sense in all primates and there is evidence that the eyesight of nocturnal species is more acute and variable than has previously been recognized. Case studies of the behaviour of a galago and a loris in open woodland habitats in relation to ambient light show that Galago moholi males are more likely to travel between clumps of vegetation along the ground when the moon is up, and during periods of twilight, whereas they retreat to more continuous vegetation and travel less when the moon sets. This is interpreted as a strategy for avoiding predators that hunt on the ground when it is dark. The travel distances of Loris lydekkerianus are not affected by moonlight but this species reduces its choice of food items from more mobile prey to mainly ants when the moon sets, indicating the importance of light when searching for high-energy supplements to its staple diet. Evidence is presented for the first time to indicate key aspects of nocturnal vision that would benefit from further research. It is suggested that the light and dark facial markings of many species convey information about species and individual identity when animals approach each other at night. Differences in the colour of the reflective eye-shine, and behavioural responses displayed when exposed to white torchlight, point to different kinds of nocturnal vision that are suited to each niche, including the possibility of some degree of colour discrimination. The ability of even specialist nocturnal species to see well in broad daylight demonstrates an inherent flexibility that would enable movement into diurnal niches. The major differences in the sensitivity and perceptual anatomy of diurnal lemurs compared to diurnal anthropoids, and the emergence of cathemerality in lemurs, is interpreted as a reflection of evolution from different ancestral stocks in very different ecosystems, and not a recent shift towards diurnality due to human disturbance., (Copyright (c) 2006 S. Karger AG, Basel.)

The risk of acquiring malaria transmitted by Anopheles baimaii Sallum & Peyton, 2005, formerly known as An. dirus species D (Sallum et al., 2005) (Diptera: Culicidae), at different hours of the night in a forest-fringed village of Assam, North-east India was assessed through all-night mosquito landing catches during 1995-2000. An estimated overall mean biting rate of 36.1 bites/person/night (95% CI = 26.2-45.8), a sporozoite rate of 1.9% (95% CI = 1.1-2.9%) and a parous rate of 58.7% (95% CI = 55.3-62.0%) were recorded. Parous and sporozoite-positive females tended to be caught mainly before midnight. The effective entomological inoculation rate was the highest (0.249 positive bites/person/night) from 21.00 to 24.00 hours, suggesting that the second quartile of the night is the most risky period for malaria transmission by An. baimaii. Considering that approximately 21% of mean inoculations take place before 21.00 hours, it appears that there is a need for appropriate protective measures during the pre-bed time period to supplement the impact of insecticide-treated nets against An. baimaii in north-east India.

Time structurally (chronomically) interpreted half-hourly monitoring of blood pressure (BP) and heart rate (HR) for at least 7 days and preferably for 17 days is recommended, separately for a diagnosis of BP disorders and when necessary again for the same or longer spans for treatment, whenever a positive diagnosis of a disorder is made. In this study, 30 clinically healthy subjects underwent 7-day monitoring and provided a series of findings, including the detection of Circadian Hyper-Amplitude-Tension (CHAT), that is blood pressure overswinging, which carries a high risk of hard cardiovascular events. The results specifically bear upon south-east Asian-Indian immigrants. They show that cardiovascular disease risk increases with age, with a positive family history of hypertension and/or other cardiovascular diseases and even with the duration of stay in the USA. A relation to body mass index is also shown. Such monitoring for prehabilitation may eventually reduce the need for rehabilitation.

This study analyzed the role of day length in regulation of seasonal body fattening and testicular growth in a latitudinal Palaearctic-Indian migrant, the redheaded bunting (Emberiza bruniceps). When exposed to increasing photoperiods (hours of light: hours of darkness; 11.5L:12.5D, 12L:12D, 12.5L:11.5D, 13L:11D, 14L:10D, and 18L:6D) for 9-12 weeks, buntings responded in a photoperiod-dependent manner and underwent growth and regression cycle under photoperiods of > or =12 hr per day. Also, the response to a long photoperiod of birds that were held under natural photoperiods at 27 degrees N for 2 years was similar to those who arrived the same year from their breeding grounds ( approximately 40 degrees N), suggesting that the experience of higher amplitude day-night (light-dark, LD) cycles during migratory and breeding seasons were not critical for the subsequent response (initiation-termination-reinitiation) cycle. Another experiment examined entrainment of the circadian photoperiodic rhythm in buntings by subjecting them to T=24+/-2 hr LD-cycles with 8 hr photophase and to T=22 and 24 hr with 11 hr photophase. The results showed a reduction in critical day length under T=22 hr LD-cycle. In the last experiment, we constructed an action spectrum for photoperiodic induction by exposing birds for 4.5 weeks to 13L:11D of white (control), blue (450 nm), or red (640 nm) light at irradiances ranging from 0.028 to 1.4 W m(-2). The threshold light irradiance for photoinduction was about 10-fold higher for blue light, than for red and white lights. These results conclude that the daily light of the environment regulates the endogenous program that times seasonal responses in body fattening and testicular cycles of the redheaded bunting.

Of 54 patients with acute coronary artery disease (CAD) that were included in this study, 41 patients had acute myocardial infarction (AMI), five patients possible MI, four patients unstable angina and the remaining four angina pectoris. The control subjects (n = 85) were randomly selected from the general population of the city of Moradabad of similar age range after exclusion for CAD (n = 9), diabetes (n = 6) and excess intake of trans fatty acids (n = 20). The incidence of lipoprotein(a) excess (> 30 mg/dl; 42.6 vs 24.7%; P < 0.05) and mean concentration of lipoprotein(a) (Lp[a], 6.4 mg/dl, 95% confidence interval: 2.8-10.5; P < 0.05) was significantly greater in the acute CAD group compared with control subjects. Mean total cholesterol and triglycerides were significantly higher and mean nitrite level lower in the study group as compared with the control group.There was a significant greater incidence of cardiac events in the second quarter of the day compared with the fourth quarter. Lp(a), triglycerides, blood glucose, plasma insulin, malondialdehyde, diene conjugates, TBARS and TNF-alpha and IL-6 levels, which were significantly greater during the acute phase, showed a significant decline and serum nitrite and coenzyme Q demonstrated an increase at 4 weeks of follow-up when the acute reactions evoked by MI had been controlled. Large breakfasts were a predisposing factor for cardiac events in the second quarter of the day and it was significantly associated with metabolic reactions. The findings indicate that acute reactions as a result or as circadian rhythms appear to be important in the pathogenesis of AMI-associated complications and that a large breakfast in association with nitrite deficiency may further trigger the circadian rhythms. However, more studies in a larger number of subjects would be necessary in order to confirm our findings.

Monosodium glutamate (MSG) was administrated chronically for 60 days to Wistar rats and 24 h rhythms of glucose, cholesterol, total protein and alkaline phosphatase were studied. MSG treatment was found to cause acrophase delays in the glucose and alkaline phosphatase rhythms and advances in acrophases of cholesterol and total protein levels. Amplitude and mesor values of these rhythms were found to be altered during MSG treatment. Glutamate levels in the brain were found to be significantly increased, which could alter these biochemical rhythms by modulating the transmission in retinohypothalamic tract and in the hypothalamic nuclei, probably including suprachiasmatic nuclei.

Five daily readings of peak expiratory flow (PEF) were obtained for three days on 100 patients with chronic stable asthma. The variability of PEF was calculated as the amplitude percent mean (A%M) from the readings obtained on the third day, and compared to previously reported data from 152 healthy Indian adults. Patients with severe asthma exhibited significantly higher A%M than patients with both mild and moderate asthma (p < 0.05), but there was considerable overlap across disease categories. The area under the receiver operating characteristic curve plotted to assess the performance of PEF variability as a discriminator in diagnosing asthma was 0.826, with best discrimination at a value of 12.5 (sensitivity 0.640, specificity 0.941). Using a cut-off value of 16.5 (as proposed earlier by us) improved specificity to 0.987 but reduced sensitivity to 0.510. Using a traditional cut-off of 20, specificity remained almost unchanged (0.993), but sensitivity dropped further to 0.440. Thus A%M>16.5 is a useful marker of bronchial asthma in epidemiological studies in India. However, its use in population screening, clinical diagnosis, or in the assessment of the severity of asthma in individual patients has serious limitations because of poor sensitivity.

The parametric or tonic effects of light were studied in a recently established diurnal circadian model-the Indian palm squirrel, Funambulus pennanti. Sixteen squirrels (7 female, 9 male) were housed individually under varying constant light conditions (0.1 lux to 46 lux) with gross locomotor activity continuously monitored. Free-running period (tau), amplitude, mesor and day-to-day stability of the activity rhythm were determined using modified periodogram and iterative harmonic analyses, while the ratio of activity to rest time was estimated by eye-fit. The main findings were as follows: 1) tau did not vary between sexes or between light conditions, although a trend for tau to lengthen when light intensity was increased was noted; 2) amplitude and mesor did not show sex differences, but both sexes showed a decrease in amplitude and mesor when light intensity was decreased; 3) the stability of the activity rhythm was greater in males than in females, and a trend was observed for rhythm stability to decrease when light intensity was reduced. These descriptive data contribute to the growing literature on this diurnal species.

Diurnal variability in peak expiratory flow (PEF) was studied for three days in 152 healthy volunteers aged 20-40 years, and expressed as amplitude percent mean (A%M) and standard deviation percent mean (SD%M). The commonest pattern (74.6%) observed was that of a nadir at waking in morning, a progressive rise upto late afternoon and a plateau or a small decrease at bedtime. Mean diurnal variation in PEF on the third day was 7.23 +/- 3.48 (A%M) and 2.98 +/- 1.31 (SD%M). Both the diurnal variation and the calculated upper limits of normality were found to be lower than those reported previously for Western subjects. This knowledge of diurnal variation is important for any meaningful interpretation of PEF recordings used to monitor patients with asthma.

To examine if there are changes in the levels of affections over different times of day, affective state measures, alertness, irritability, mental tension, headache and anxiety of 100 female staff nurses were assessed, on visual analogue scales at 2-h intervals over a 24-h work cycle spread over three different shift works. Oral temperature was also recorded simultaneously. Sleep pattern, dietary habit and menstruation cycle of subjects were monitored. Analysis of variance reflected a significant rise in oral temperature as the day progressed with a peak during 16:00-18:00 h, which however gradually declined thereafter. Significant changes in the affective states indicated ascendancy in alertness, mental tension and anxiety within the first few hours of the beginning of each shift work, but descendancy towards the end of it. Further studies on some more affective states and physiological measures which may show parallelism have been suggested.

Urinary citrate excretion was estimated colorimetrically from urine samples collected every 3 h for 24 h from 25 healthy adult males (non-stone formers; mean age 39 +/- 7 years) and 25 male patients suffering from calcium nephrolithiasis (stone formers; mean age 41 +/- 6 years). The 24 h citrate excretion was 2.47 +/- 0.65 mmol in non-stone formers and 2.02 +/- 0.71 mmol in stone formers. This difference was not significant. However, cosinor rhythmometry revealed a significant circadian rhythmicity in urinary citrate excretion in the healthy males which was absent in the stone formers; the amplitude was 0.06 mmol in non-stone formers and 0.017 mmol in stone formers. The acrophase was located at 14:25 h in non-stone formers and at 23:30 h in stone formers.

Circulatory levels of growth hormone (GH) were estimated at 0600 h, 1200 h, 1800 h and 2400 h in each of 10 subjects of sea level residents (SLR) in New Delhi (226 m) and in high altitude natives (HAN) settled at an altitude of 3650 m. Both in SLR and HAN the GH secretion showed an identical pattern, the values were lowest at 0600 h and highest at 2400 h. Nevertheless, in HAN the GH levels at different timings of the day were found to be significantly higher than in SLR.

Circadian rhythm of serum urea concentration was studied in 25 clinically healthy, diurnally active, nocturnally resting young male Indians. The mean urea concentration was observed to be 22.32 mg/dl at 0800 h which increased gradually reaching maximum at 0000 h with a mean of 31.00 mg/dl. A marked circadian variation in serum urea was recorded with a statistically significant amplitude and acrophase at 2232 h (Cosinor analysis). The observation that serum urea concentration oscillates physiologically in the peripheral blood according to a circadian rhythm may prove to be of importance in the clinical interpretation of values at different times along the 24 h light-dark period.