Relationship between smoking, dietary intakes and plasma levels of vitamin E and beta-carotene in matched maternal-cord pairs.

The concentrations of tocopherols and carotenoids are lowered in umbilical cord blood plasma, which may have a negative effect on antioxidant protection in neonates. Smoking may adversely affect dietary intakes and plasma concentrations of carotenoids. The dietary intakes of vitamin E and beta-carotene were assessed in 66 pregnant women (31 smokers and 35 non-smokers) between 10 and 20 weeks gestation using a food frequency questionnaire. The concentrations of alpha-tocopherol and beta-carotene were measured in maternal plasma at the time of the dietary assessment, and in the matched umbilical cords of their newborn after delivery. In smoking and non-smoking mothers, the mean intakes of vitamin E (9.3 [SD 5] and 8.2 [SD 5] mgd-1) and beta-carotene (3464 [SD 1885] and 2977 [SD 1503] micrograms d-1) were not significantly different. The plasma concentrations of alpha-tocopherol (20.8 [SD 4] and 20.5 [SD 4] mumol L-1), the alpha-tocopherol to lipid ratios (3.2 [SD 0.8] and 3.5 [SD 0.8]) and the plasma concentrations of beta-carotene (0.22 [SD 0.1] and 0.22 [SD 0.1] mumol L-1) were not significantly different in smoking and non-smoking mothers. There were no significant differences in plasma alpha-tocopherol (7.4 [SD 2] and 7.3 [SD 2] mumol L-1), in alpha-tocopherol to lipid ratios (3.2 [SD 0.6] and 2.8 [SD 0.6]) or in beta-carotene concentrations (0.05 [SD 0.04] and 0.03 [SD 0.02] mumol L-1) in cords from newborns of smoking and non-smoking mothers. There was a significant correlation (r = 0.41, P = 0.015) between dietary intakes and plasma concentrations of beta-carotene in non-smoking mothers. However, this relationship was not significant in smoking mothers (r = 0.28, P = 0.12). There were no relationships between dietary intakes and plasma concentrations of tocopherol. These results indicate that smoking during pregnancy does not appear to affect the dietary intakes or plasma concentrations of alpha-tocopherol and beta-carotene in pregnant women or their babies. However, smoking does influence the relationship between dietary intakes and plasma levels of beta-carotene.     

Abstracts

Clinical Autonomic Research Society Proceedings

Abstracts     

Isolated corticotropin deficiency in chronic alcoholism

Three patients who chronically abused alcohol were found to be hyponatraemic with normal plasma potassium. The first had been admitted with confusion and weight loss, the second with hypotension and sepsis, and the third with confusion and hypoglycaemia-induced seizures. All three patients had a subnormal cortisol response in the short synacthen test; however, the plasma cortisol after three days of tetracosactrin administration was greater than 550 nmol/L. Baseline corticotropin levels were less than 10 pg/mL in all three. No structural lesions of the hypothalamo-pituitary tract were found and there was no evidence of other endocrinopathies. Glucocorticoid replacement therapy led to the resolution of hyponatraemia and hypoglycaemia, where present, and to clinical improvement. The two surviving patients remained hypocortisolaemic in the long term, without recurrence of hyponatraemia or hypoglycaemia. The features of isolated corticotropin deficiency are easily confused with other effects of chronic alcohol abuse. In alcoholic patients with unexplained hyponatraemia, hypoglycaemia or haemodynamic instability, a short tetracosactrin test is advisable.     

Assembly and Maturation of a T = 4 Quasi-Equivalent Virus Is Guided by Electrostatic and Mechanical Forces

Nudaurelia capensis ω virus (NωV) is a eukaryotic RNA virus that is well suited for the study of virus maturation. The virus initially assembles at pH 7.6 into a marginally stable 480-Å procapsid formed by 240 copies of a single type of protein subunit. During maturation, which occurs during apoptosis at pH 5.0, electrostatic forces guide subunit trajectories into a robust 410-Å virion that is buttressed by subunit associated molecular switches. We discuss the competing factors in the virus capsid of requiring near-reversible interactions during initial assembly to avoid kinetic traps, while requiring robust stability to survive in the extra-cellular environment. In addition, viruses have a variety of mechanisms to deliver the genome, which must remain off while still inside the infected cell, yet turn on under the proper conditions of infection. We conclude that maturation is the process that provides a solution to these conflicting requirements through a program that is encoded in the procapsid and that leads to stability and infectivity.     

Sleep and Sleep-Wake Disturbances in Care Recipient-Caregiver Dyads in the Context of a Chronic Illness: A Critical Review of the Literature

ContextAlterations in sleep-wake patterns of care recipients and their informal caregivers are common in the context of a chronic illness. Given the current notion that sleep may be regulated within and affected by close human relationships, concurrent and interrelated sleep problems may be present in care recipient-caregiver dyads.ObjectivesTo critically analyze evidence regarding concurrent sleep patterns or changes in care recipient-caregiver dyads in the context of a chronic illness and address methodological and research gaps.MethodsUsing a wide range of key terms and synonyms, three electronic databases (Medline, CINAHL, and Embase) were systematically searched for the period between January 1990 and July 2011.ResultsTen studies met prespecified selection criteria and were included for analysis. Study quality was fair to good on average. Seven studies were conducted in the context of dementia or Parkinson's disease, two in the context of cancer, and one study included a group of community elders with mixed related comorbidities and their informal caregivers. Bidirectional associations in the sleep of care recipient-caregiver dyads seem to exist. Concurrent and comparable nocturnal sleep disruptions also may be evident. Yet, inconsistencies in the methods implemented, and the samples included, as well as uncertainty regarding factors coaffecting sleep, still preclude safe conclusions to be drawn on.ConclusionThe dyadic investigation of sleep is a promising approach to the development of truly effective interventions to improve sleep quality of care recipients and their caregivers. Nevertheless, more systematic, longitudinal dyadic research is warranted to augment our understanding of co-occurrence and over time changes of sleep problems in care recipient-caregiver dyads, as well as to clarify covariates/factors that appear to contribute to these problems within the dyad and across time and context of illness.