Rohit Pradhan - Academia.edu (original) (raw)

Papers by Rohit Pradhan

Biological Rhythm Research, 2012

Sickle cell disease (HbSS) is the most common variant of β-globin gene, resulting from the replac... more Sickle cell disease (HbSS) is the most common variant of β-globin gene, resulting from the replacement of glutamic acid by valine at position 6 in the β chain. Under the action of certain factors, such as cold, fever, dehydration, and infections, sickle cell crisis is usually precipitated. The crisis predisposes to aggregation of sickle cells, which may produce vaso-occlusion of capillaries, resulting in pain, swelling, and infarction. In response to inflammation, the liver releases a variety of acute phase proteins. C-reactive protein (CRP) is pentameric hepatocyte protein and is the measure marker of the “acute phase response,” or the formation of plasma proteins in response to an inflammatory stimulus in human. This study is an attempt to document diurnal variations in the level of CRP in sickle cell disease (SCD) patients in steady or crisis state. Saliva samples from SCD, sickle cell trait (SCT), and control subjects were collected continuously over a period of three days. C-reactive protein level was detected using RHELAX CRP Latex kit with the sensitivity of 0.6 mg/dl. When pooled data were subjected for Cosinor rhythmometry, it failed to detect sinusoidality among SCD patients suggesting a constant elevated level of CRP level due to inflammation. However, a statistically significant circadian variation among control and SCT in CRP levels was discerned. Result suggests that although the level of CRP in SCT is comparatively higher than the normal individuals, the CRP contents significantly fluctuate in the absence of chronic inflammation among traits. The rhythm-adjusted mean was found to be significantly higher in SCD (p ≤ 0.005) patients when compared to control and trait subjects. A constant higher level of CRP can also be an indicator of future cardiac complications in SCD patients.

Biological Rhythm Research, 2011

Sleep quality is a main indicator of health and well-being. Poor sleep indicates stress factors i... more Sleep quality is a main indicator of health and well-being. Poor sleep indicates stress factors in the living environment or a health-compromising lifestyle with increases in the synthesis of C-reactive protein (CRP). We hypothesized that the level of CRP – a marker of stress and excessive daytime sleepiness (EDS) – increases as a function sleep deprivation. Randomly selected 2,105 subjects from the urban, rural (villages with electricity) and remote (villages without electricity) of Chhattisgarh, India were included in the study. Sleep behaviour was studied with the help of a questionnaire and EDS was quantified using the Epworth Sleepiness Scale (ESS). Average nocturnal sleeps of peoples living in remote, rural and urban areas were found to be 8:56 hr, 8:29 hr and 6:55 hr, respectively. A statistically significantly rise in the prevalence of EDS was observed as a function of habitat with 3% in remote, 7.8% in rural and 27.69% in urban areas. The salivary CRP level of people living in urban areas is significantly higher (6.0 ± 0.25 mg/dl) than rural (2.7 ± 0.53 mg/dl) or remote (2.1 ± 0.48 mg/dl) populations (p < 0.001). Further, a heightened association between intensity of sleepiness and level of CRP was also witnessed (p < 0.001). Elevated CRP contents among EDS subjects indicate a higher stress level in sleep-deprived individuals. The findings of the present study suggest that CRP levels may be an index of sleep deprivation and existence of excessive sleepiness during daytime.

Journal of Indian Association of Pediatric Surgeons, 2008

Presence of thymus in the normal position as well as in the posterior mediastinum is an unusual p... more Presence of thymus in the normal position as well as in the posterior mediastinum is an unusual phenomenon. We report here a case of posterior mediastinal mass in a 20-month old male child who presented with dysphagia and dry cough. Investigations revealed it to be a solid posterior mediastinal mass, suspected to be either lymphoma or a neuroblastoma. Excision of the mass followed by histopathologic examination revealed the mass to be a normal thymus. This case indicates that a benign mass, an accessory thymus, though rare, can be located in the posterior mediastinum and cause symptoms similar to solid mediastinal tumors.

Biological Rhythm Research, 2008

The objective of this study was to explore the impact of permanent night shift on rest–activity r... more The objective of this study was to explore the impact of permanent night shift on rest–activity rhythm in 20 randomly selected male permanent night workers, employed in a local newspaper printing office. The machine operators performed their job from 20:00 to 04:00 and the computer operators from 18:00 to 02:00 every day. The night workers availed one-day rest after working six consecutive days. Twenty-one age- and gender-matched day workers were also studied for comparison of rhythm parameters. In each subject rest–activity rhythm was monitored non-invasively by using Actiwatch (AW64 Mini Mitter Co. Inc., USA). Data were gathered at one-minute intervals for seven consecutive days. In addition, all subjects also responded to the morningness-eveningness questionnaire (Horne and Östberg's MEQ). Data were stored in the form of records and analyzed with the help of Actiware sleep software, Cosinor rhythmometry, Power spectrum analysis, Autocorrelation, ANOVA and Duncan's multiple range test, t-test and descriptive statistics. Rhythm parameters were computed at two different fixed windows, namely τ = 24 h and τ = 12 h. Harmonic means were calculated for those parameters obtained at both windows. All permanent night workers and day workers exhibited statistically significant circadian rhythm in rest–activity profile. At least five permanent night workers exhibited prominent non-circadian period. Statistically significant differences were observed between the rhythm characteristics of permanent night workers and day workers. The circadian 24-h average of activity in computer operators was significantly lower compared to that of the machine operators and day workers. Circadian amplitude of both machine operators and computer operators was significantly lower than that of day workers. Further, the peak appeared significantly later in machine operators (18.1 h) than that of the computer operators (16.8 h) and the day workers (10.9 h). The value of r24 was also lower in permanent night workers compared with that of the day workers. Results of this study conclusively demonstrate that permanent night shift alters circadian rhythm characteristics of rest–activity in night workers significantly and the changes were independent of the factors age and to the most extent chronotype. These might force permanent night workers to face negative health consequences in future.

Chronobiology International, 1989

Phototactic responses of three groups, each of 16 cave fishes, were observed at 4-hr intervals be... more Phototactic responses of three groups, each of 16 cave fishes, were observed at 4-hr intervals beginning at 0900, following 5 days of acclimation inside specially designed aquaria. The latter consisted of two parts, a photic zone and an aphotic zone. The first group of fishes were fed ad libitum, while the second and third group of fishes were fed with minced mutton and/or liver delivered in the photic zone between 0700-1100, and in the aphotic zone between 1900-2100. The percentage of fishes present in the photic zone at a given time was used as a measure of their phototactic responses. Single cosinor analysis of these data has revealed, for the first time, a circadian rhythmicity in the phototactic behaviour of a cavernicolous organism. However, imposition of restricted feeding schedules shifted the peak time of the circadian rhythm in phototactic responses. Meal scheduling may thus be an effective synchronizer for this behavioural rhythm.

Total protein content in blood serum and different lymphoid organs, such as bursa, spleen and thy... more Total protein content in blood serum and different lymphoid organs, such as bursa, spleen and thymus was investigated in chickens at two different circadian stages (0800 or 1600 hrs; early or late photophase) following administration of either saline or hormones (thyroxine or hydrocortisone or epinephrine). The results suggest that the lymphoid organs may respond differently to the exogenous administration of different hormones depending on the time of their administration.

Present study is an attempt to know the existence of colour change physiology of the cave fish Ne... more Present study is an attempt to know the existence of colour change physiology of the cave fish Nemaeheilus evezardi (Day) along a circadian time scale. Though, due to subterranean mode of life, practically this function has no survival value. The study has been conducted simultaneously in two different photoperiodic conditions (LD 00: 24 and LD 12: 12 hr). The variation in different states of chromatophore have been computed with respect to different time points of the day. Results suggest that the phenomenon is lying completely disturbed in its in situ conditions. Interestingly, circadian rhythm in all the types of chromatophores were validated when the same fish was exposed under LD 12: 12 hr photoperiod.

General and Comparative Endocrinology, 1989