Night-time diuresis pattern in children with and without primary monosymptomatic nocturnal enuresis.

INTRODUCTION: Night-time polyuria as the dominating pathophysiological mechanism for primary monosymptomatic nocturnal enuresis (PMNE) has been put in question with nocturnal detrusor overactivity and high arousal thresholds as alternatives. An earlier finding of night-time polyuria in 12% of healthy non-enuretic schoolchildren underscores that excessive night-time diuresis per se is unlikely the major cause of PMNE. OBJECTIVE: The objective of this study was to compare the night-time diuresis pattern in children with and without PMNE and to evaluate the role of night-time polyuria in provoking enuretic episodes in children with PMNE. STUDY DESIGN: Night-time diuresis pattern was recorded in 27 children with PMNE, aged 6-15 years, and 29 non-enuretic children, aged 6-13 years. Using a portable ultrasound recorder, the bladder volume was estimated at 15-min intervals for at least three nights with the child sleeping in its own bed at home. The volume of enuretic episodes was controlled using preweighed diapers. All voids were registered by time and volume. Diuresis during night time was estimated from the slope of regression lines fitted to ultrasound recording points. Mean night-time diuresis was calculated from total urine production during the night and time interval from the last void before bedtime to the first morning void. RESULTS: Night-time bladder filling pattern was recorded from 189 nights, giving 149 interpretable patterns for analysis (77 children with PMNE and 72 dry children). The night-time diuresis pattern was similar for children with or without PMNE, showing large variability between different nights of the same child. Most nights displayed a smooth bladder filling at constant low rate, whereas other nights showed an early phase with high diuresis followed by a longer period of low diuresis with no difference between the two groups. DISCUSSION: Night-time diuresis has been non-invasively monitored in children while asleep in their own beds at home. The pattern of night-time diuresis varies considerably between different nights of the same child, with no obvious differences in any diuresis parameters between children with or without PMNE. CONCLUSION: Non-enuretic children have similar diuresis pattern and maximal night-time diuresis values as children with PMNE, making it unlikely that PMNE is caused by night-time polyuria per se (Summary figure). Delayed maturation of sleep mechanisms such as decreased arousability or sleep inhibition of the micturition reflex is more likely to be the main etiology for enuresis.

ICP-MS and LC-ICP-MS for analysis of trace element content and speciation in cereal grains.

Trace elements are unevenly distributed and speciated throughout the cereal grain. The germ and the outer layers of the grain have the highest concentrations of trace elements. A large fraction of the trace elements is therefore lost during the milling process. The bioavailability of the remaining trace elements is very low. This is usually ascribed to the formation of poorly soluble complexes with the phosphorus storage compound phytic acid. Hence, analysis of the total concentration of trace elements in grain tissues must be combined with a speciation analysis in order to assess their contribution to human nutrition. This chapter deals with the fractionation of anatomically very different cereal tissues. Procedures for microscaling of digestion procedures are outlined together with requirements for the use of certified reference materials in elemental profiling of grain tissue fractions. Methods for extraction and analysis of complexes containing trace elements in the grain tissue fractions are described. Finally, the chapter concludes with criteria for choice of chromatographic methods and setting of ICP-MS instrument parameters.

Survival in extreme environments - on the current knowledge of adaptations in tardigrades.

Tardigrades are microscopic animals found worldwide in aquatic as well as terrestrial ecosystems. They belong to the invertebrate superclade Ecdysozoa, as do the two major invertebrate model organisms: Caenorhabditis elegans and Drosophila melanogaster. We present a brief description of the tardigrades and highlight species that are currently used as models for physiological and molecular investigations. Tardigrades are uniquely adapted to a range of environmental extremes. Cryptobiosis, currently referred to as a reversible ametabolic state induced by e.g. desiccation, is common especially among limno-terrestrial species. It has been shown that the entry and exit of cryptobiosis may involve synthesis of bioprotectants in the form of selective carbohydrates and proteins as well as high levels of antioxidant enzymes and other free radical scavengers. However, at present a general scheme of mechanisms explaining this phenomenon is lacking. Importantly, recent research has shown that tardigrades even in their active states may be extremely tolerant to environmental stress, handling extreme levels of ionizing radiation, large fluctuation in external salinity and avoiding freezing by supercooling to below -20 °C, presumably relying on efficient DNA repair mechanisms and osmoregulation. This review summarizes the current knowledge on adaptations found among tardigrades, and presents new data on tardigrade cell numbers and osmoregulation.

Traumatic Retroperitoneal Injuries: Review of Multidetector CT Findings.

Multidetector computed tomography (CT) represents a significant advance in CT technology and can allow the accurate assessment of trauma patients, including the detection of traumatic retroperitoneal injuries, many of which are clinically occult. Retroperitoneal injuries include duodenal, pancreatic, vascular, renal, and adrenal injuries. Abnormal blood, fluid, or air within the retroperitoneal spaces may be isolated findings but can also occur in association with these injuries, and their recognition is the key to correctly identifying the injury. Accurate characterization of injury with CT can affect clinical management and can help minimize unnecessary laparotomies. Equivocal findings at initial abdominal CT should prompt close clinical follow-up with possible imaging follow-up, particularly for suspected occult duodenal and pancreatic injuries.

Electrophysiological and behavioral activity of secondary metabolites in the confused flour beetle, Tribolium confusum.

Several previous studies have addressed pheromone communication in various flour beetles (Coleoptera: Tenebrionidae), including the confused flour beetle, Tribolium confusum (du Val). Different stereoisomers of 4,8-dimethyldecanal (DMD) were reported as the only components of an aggregation pheromone, but the behavioral activity of DMD is low. In the present study, additional previously reported secondary metabolites (benzoquinones and hydrocarbons) were tested for electrophysiological activity (EAG) with both sexes of T. confusum. Two benzoquinones and three monoenic hydrocarbons elicited significant EAG activity from both male and female antennae. There was an elevated male EAG response (vs. the females) to two out of the three hydrocarbons and for both quinones. The EAG-active compounds were subsequently investigated for behavioral activity in a walking bioassay. Benzoquinones are considered toxic and have been assigned a function as alarm substances in flour beetles, but we found that methyl-1, 4-benzoquinone in intermediate concentrations was attractive to both male and female beetles and could therefore act as an aggregation pheromone component. Males were also attracted to ethyl-1,4-benzoquinone. The corresponding hydroquinones, presumed precursors of the benzoquinones, did not elicit any electrophysiological response and were not tested for behavioral activity. The unsaturated hydrocarbons (1-tetradecene, 1-pentadecene, and 1-hexadecene) elicited significant EAG responses from both male and female antennae and were also attractive in the behavioral assay. Our results show that several beetle-produced compounds, in addition to 4,8-dimethyldecanal, may be part of a complex pheromone system in flour beetles and play a role in mediating aggregation in T. confusum.

Penetratin-induced aggregation and subsequent dissociation of negatively charged phospholipid vesicles.

The interaction of the cellular delivery vector penetratin with a model system consisting of negatively charged phospholipid vesicles has been studied. Above a certain peptide to lipid molar ratio, the cationic oligopeptide induces vesicle aggregation. Interestingly, the aggregation is followed by spontaneous disaggregation, which may be related to membrane translocation of the peptide. Circular dichroism (CD) measurements indicate a conformational transition, from alpha-helix to antiparallel beta-pleated sheet, which is simultaneous with the aggregation process. The potential influence of spectroscopic artifacts on CD data due to the drastically increased turbidity during aggregation is discussed.

The antennapedia peptide penetratin translocates across lipid bilayers - the first direct observation.

The potential use of polypeptides and oligonucleotides for therapeutical purposes has been questioned because of their inherently poor cellular uptake. However, the 16-mer oligopeptide penetratin, derived from the homeodomain of Antennapedia, has been reported to enter cells readily via a non-endocytotic and receptor- and transporter-independent pathway, even when conjugated to large hydrophilic molecules. We here present the first study where penetratin is shown to traverse a pure lipid bilayer. The results support the idea that the uptake mechanism involves only the interaction of the peptide with the membrane lipids. Furthermore, we conclude that the translocation does not involve pore formation.

Voiding pattern in healthy newborns.

A 4-hour observation period has been used in infants to investigate suspected bladder dysfunction. The aim of the present study was to extend the usefulness of this protocol by establishing reference values for voiding frequency, intervals, volumes, and residual urine in healthy newborns. The study included 51 healthy newborns, 26 girls and 25 boys, aged 3 to 14 days. During a 4-hour period, all micturitions and residuals were recorded as well as feeding, sleeping, crying, and defecations. The observation was completed with the child undressed to observe the urinary stream during one void. Different provocation tests were tried to induce urinary leakage. All newborns voided with a stream, about once per hour, with a median volume of 23 mL. For each voiding parameter, there was a large inter- and intra-individual variability. Double voidings were common as well as sizable residual volumes. The diuresis was about six times higher than in healthy school children. The healthy newborns did not leak during provocation tests such as manual compression of the bladder. Neurourol. Urodynam. 19:177-184, 2000.

Occupation and survival: a 25-year follow-up study of an aging population.

OBJECTIVE: In this retrospective study of an elderly population cohort living in a defined Swedish rural area, the relationship between occupation and survival as a measure of objective health was investigated. The cohort has been followed for 25 years. METHOD: On the basis of the baseline socioeconomic interview from assessments performed when the participants were 67 years of age, an index of active participation in daily occupation was devised. The index was used to investigate the covariation between generic everyday occupation and long-time survival. RESULTS: For the female participants, Kaplan-Meier curves demonstrated differences in survival between the "less active" and "more active," and Cox regression survival analyses resulted in a significant covariance between occupation and survival. For the male participants, no such differences were found. CONCLUSION: The significant results for the women implied support for the core assumption of occupational therapy that a relationship exists between occupation and health. The lack of differences in survival among more active and less active men demonstrates the complexity of studying occupation.

The elderly driver: deciding when to stop.

This study examines the decision of people (N = 56) living in retirement communities to quit driving, and the role of their physician and family in making this decision. Most of the elderly stopped driving when a threshold was reached after an accumulation of compensatory behaviors. Few stopped because of their doctor's advice, although all felt a physician was in the best position to evaluate driving, and family involvement received limited support.

The condensation of DNA by chromium (III) ions.

Cr(III), one of the most potent inorganic carcinogens, induces condensation of DNA into a very compact product at 37 degrees, as shown by electron microscopy. The condensation begins with the appearing of some supercoil structures and complete condensation occurs at relatively low Cr(III) concentrations; for 3 and 30 mM ionic strength they are 4.5 and 45 microM, respectively. Under these conditions, Cr(III) inhibits the interaction between ethidium and DNA as shown by absorption and fluorescence spectra.

Cr(III)-Induced polymerization of human albumin : A small-angle X-ray scattering study of an allergen for chromium contact dermatitis.

Chromium (III)-albumin complexes that have allergenic properties and induce contact dermatitis are aggregated in solution. This is shown by small-angle X-ray scattering of Cr(III)-albumin solutions at 21°C in a Tris-HCl buffer of pH=7.40.At high concentrations of Cr(III), albumin appears to aggregate to an average molecular weight of an octamer, with an average gyration radius of 116 Å. At low concentration of Cr(III), dimers and also some higher polymers form with an average molecular weight of 135,000 and an average radius of gyration of 57 Å.Analysis of the shapes of the Cr(III)-albumin complexes indicate that they are more elongated than albumin, suggesting that, in the presence of Cr(III), the albumin molecules associate sideways with an expansion mainly of the largest axis.

Copper(I) complexes of penicillamine and glutathione.

Equilibrium analysis of a model system for the in vivo reactions between penicillamine and Cu(I), the penicillamine-glutathione-Cu(I) system, indicates that in a certain concentration range the use of penicillamine as a drug will not disturb the normal Cu(I) metabolism. The equilibrium data required for this analysis were obtained by emf titrations on the Cu(I)-glutathione (H3A) and the Cu(I)-pencillamine (H2A) systems at 25 degrees C. in 0.5 M NaClO4 medium, using glass and copper amalgam electrodes; the data were analyzed first by various graphical methods and then by a general least squares computer program. The results show that mononuclear Cu(I) species Cu(HA)2 form in both systems with stability constants log beta 122 of 38.8 (glutathione) and 39.18 (penicillamine); in addition, the polynuclear Cu5A43- species forms in the penicillamine system and the mononuclear CuHA- species might form in the glutathione system. The results are discussed in relation to the therapeutic use of penicillamine as well as in relation to the toxic action of copper on living cells.