Increase in 6-hydroxymelatonin excretion in humans during ascent to high altitudes

Melatonin (MLT), the pineal gland hormone involved in the regulation of circadian rhythms, shows characteristic diurnal variation. Its physiological role in humans is not clear. Exposure to high altitudes may disrupt the circadian rhythm and lead to various endocrine changes. MLT in humans has not been studied under these conditions. Urinary 6-hydroxy-MLT sulfate (aMT6s) excretion was analyzed during the day (0700-2200 h) and night (2200-0700 h) phases. A cohort of 33 healthy volunteers, aged 19-65 yr, was studied during an ascent to a high altitude in the Himalayas on three occasions (at a lower altitude, at 3400 m, and after reaching maximal altitudes of 5600-6100 m). aMT6s excretion during the daytime remained unchanged during exposure to high altitudes. As expected, nocturnal values were higher than diurnal values at each point in time. However, there was a significant increase in nocturnal MLT excretion after the ascent to high altitudes. Ascent to high altitudes is associated with increased nocturnal excretion of aMT6s. The mechanism and physiological significance of this MLT increase are unclear.     

Late-onset intermittent fasting dietary restriction as a potential intervention to retard age-associated brain function impairments in male rats

Lifelong dietary restriction (DR) is known to have many potential beneficial effects on brain function as well as delaying the onset of neurological diseases. In the present investigation, the effect of late-onset short-term intermittent fasting dietary restriction (IF-DR) regimen was studied on motor coordination and cognitive ability of ageing male rats. These animals were further used to estimate protein carbonyl content and mitochondrial complex I-IV activity in different regions of brain and peripheral organs, and the degree of age-related impairment and reversion by late-onset short-term IF-DR was compared with their levels in 3-month-old young rats. The results of improvement in motor coordination by rotarod test and cognitive skills by Morris water maze in IF-DR rats were found to be positively correlated with the decline in the oxidative molecular damage to proteins and enhanced mitochondrial complex IV activity in different regions of ageing brain as well as peripheral organs. The work was further extended to study the expression of synaptic plasticity-related proteins, such as synaptophysin, calcineurin and CaM kinase II to explore the molecular basis of IF-DR regimen to improve cognitive function. These results suggest that even late-onset short-term IF-DR regimen have the potential to retard age-associated detrimental effects, such as cognitive and motor performance as well as oxidative molecular damage to proteins.     

The tuberculin specificity in humans of Mycobacterium tuberculosis antigen 5

Mycobacterium tuberculosis antigen 5 is a protein antigen limited in distribution to M. tuberculosis and M. bovis and capable of eliciting typical delayed tuberculin skin test reactions in humans. A single large batch of this antigen was purified by immunoabsorbent affinity chromatography and used to skin test patients with tuberculosis and other mycobacterial infections and healthy persons in general populations in geographic areas where nonspecific tuberculin reactivity is frequently encountered. Antigen 5 was found to be no more specific as a tuberculin antigen than PPD. If the available data are accepted, then either a disparity in antigen recognition by antibody and T lymphocytes may exist or the widely accepted hypothesis attributing nonspecific tuberculin reactivity to antigenic cross reactivity with other mycobacteria may be incorrect.     

Laparoscopic Drainage of a Large Pancreatic Pseudocyst

Laparoscopic cystogastrostomy is an established procedure for the drainage of pancreatic pseudocysts. Cysts are mainly present in the lesser sac (retro-gastric), which is completely amenable to cystogastrostomy. We discuss the problems faced and simple solutions to the problems in managing a huge pancreatic pseudocyst of 22 cm×18 cm in a young boy 18 y of age.     

Ogilvie's syndrome of colonic pseudo-obstruction: A complication of radical hysterectomy with pelvic and paraaortic lymphadenectomy

Ogilvie's syndrome of colonic pseudo-obstruction has been reported in a wide variety of systemic disorders including blunt and surgical trauma but apparently not as a complication of radical hysterectomy with pelvic and paraaortic lymphadenectomy. Its occurrence following extensive paraaortic dissection in this case but no report so far of its occurrence after routine radical hysterectomy supports the most commonly proposed etiology of disturbed splanchnic nerve supply to the colon as a cause. Colonic pseudo-obstruction following radical hysterectomy with pelvic and paraaortic lymphadenectomy is reported and the etiology, diagnosis, and management are discussed to highlight the condition so that possible associated morbidity/mortality may be avoided.