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The discovery of aquaporin-1 (AQP1) by Agre and associates answered the longstanding biophysical question of how water specifically crosses biological membranes. In the kidney at least 7 aquaporins are expressed at distinct sites. AQP1 is extremely abundant in the proximal tubule and descending thin limb and is essential for urinary concentration. AQP2 is exclusively expressed in the principal cells of the connecting tubule and collecting duct and is the predominant vasopressin-regulated water channel. AQP3 and AQP4 are both present in the basolateral plasma membrane of collecting duct principal cells and represent exit pathways for water reabsorbed apically via AQP2. Studies in patients and transgenic mice have shown that both AQP2 and AQP3 are essential for urinary concentration. Three additional aquaporins are present in the kidney. AQP6 is present in intracellular vesicles in collecting duct intercalated cells and AQP8 are present intracellularly at low abundance in proximal tubules and collecting duct principal cells but the physiological function of these 2 channels remain undefined. AQP7 is abundant in the brush border of proximal tubule cells and is likely to be involved in proximal tubule water reabsorption. A series of studies have underscored crucial roles of aquaporins for regulation of renal water metabolism and hence body water balance. Moreover it has become clear that dysregulation of aquaporins, and especially AQP2 is critically involved in many water balance disorders. Lack of functional AQP2 is seen in primary forms of diabetes insipidus, and reduced expression and targeting is seen in several diseases associated with urinary concentrating defects such as acquired nephrogenic diabetes insipidus, postobstructive polyuria, as well as acute and chronic renal failure. In contrast, in conditions with water retention such as severe congestive heart failure, pregnancy and SIADH both AQP2 expression levels and apical plasma membrane targetting is increased suggesting a role for AQP2 in the development of water retention. Continued analysis of the aquaporins is providing detailed molecular insight into the fundamental physiology and pathophysiology of water balance and water balance disorders.

We previously published a method for measuring several physiological traits causing obstructive sleep apnea (OSA). The method, however, had a relatively low success rate (76%) and required mathematical modeling, potentially limiting its application. This paper presents a substantial revision of that technique. To make the measurements, continuous positive airway pressure (CPAP) was manipulated during sleep to quantify 1) eupneic ventilatory demand, 2) the level of ventilation at which arousals begin to occur, 3) ventilation off CPAP (nasal pressure = 0 cmH2O) when the pharyngeal muscles are activated during sleep, and 4) ventilation off CPAP when the pharyngeal muscles are relatively passive. These traits could be determined in all 13 participants (100% success rate). There was substantial intersubject variability in the reduction in ventilation that individuals could tolerate before having arousals (difference between ventilations #1 and #2 ranged from 0.7 to 2.9 liters/min) and in the amount of ventilatory compensation that individuals could generate (difference between ventilations #3 and #4 ranged from −0.5 to 5.5 liters/min). Importantly, the measurements accurately reflected clinical metrics; the difference between ventilations #2 and #3, a measure of the gap that must be overcome to achieve stable breathing during sleep, correlated with the apnea-hypopnea index (r = 0.9, P < 0.001). An additional procedure was added to the technique to measure loop gain (sensitivity of the ventilatory control system), which allowed arousal threshold and upper airway gain (response of the upper airway to increasing ventilatory drive) to be quantified as well. Of note, the traits were generally repeatable when measured on a second night in 5 individuals. This technique is a relatively simple way of defining mechanisms underlying OSA and could potentially be used in a clinical setting to individualize therapy.

Ocimum gratissimum is used in popular medicine to treat painful diseases. The antinociceptive properties of O. gratissimum essential oil (OgEO) and two of its active principles (eugenol and myrcene) were tested in classic models of pain (hot plate test and formalin test). Adult male C57BL/6 J mice acutely received corn oil (control group, p.o.), morphine (positive control group, 5 mg/kg, i.p.), OgEO (10, 20, or 40 mg/kg, p.o.), eugenol or myrcene (both at 1, 5, or 10 mg/kg, p.o.). The highest doses of all tested drugs significantly increased the latency to lick the paw(s) in the hot plate test compared with the control group. OgEO at a dose of 40 mg/kg and eugenol and myrcene at a dose of 10 mg/kg were effective in minimizing animal pain in the first and second phases of the formalin test. The antinociceptive effect shown by all drugs tested in hot plate test was reverted by naloxone administration (1 mg/kg), indicating opiod system participation. These results demonstrate the beneficial effects of OgEO and its active principles against neurogenic and inflammatory pain. Our findings demonstrate that OgEO and its isolated active principles exhibited antinociceptive activity in murine pain models.

In foods, unsaturated lipids are often present as dispersed phases, that favours their oxidation, limiting extended shelf-life of unsaturated lipid-enriched products. Proteins, that are present in the aqueous phase or participate to the stabilization of the dispersions also intervene in the oxidation process. Our work was aimed at investigating oxidation of oil-in-water emulsions stabilized by proteins. Model emulsions were aged at 50°C in sealed tubes. Oxidation was followed by complementary methods allowing evaluation of substrate consumption and formation of free radicals, primary and secondary lipid oxidation products and lipid oxidation- protein reaction products. The odour and the physical stability of the emulsions were also evaluated. According to chelating and free radical scavenging properties of the protein emulsifier, the availability of the metal ions in the medium or the initial pH of the aqueous phase lipid oxidation was significantly delayed or promoted. Differences in the relative compositions of the volatile fraction indicated that oxidation mechanism were modulated by emulsifier and pH of the aqueous phase. The reaction continued after total consumption of oxygen leading to continuous formation of volatile compounds, lipid-protein fluorescent interaction products and changes in the odour of the emulsions. Investigation of the effect of emulsion droplet size on oxidation gave different pictures according to the marker. These results, combined with others of the literature, highlight the need to consider the oxidation of multiphase food systems as a multidimensional phenomenon that involve all food components and phases and should be investigated as different time and space scales.

The present study sought to evaluate concomitant alterations of behavioral and sleep patterns of arthritic rats. Rats were implanted with electrodes for polysomnographic recordings and submitted to the model of arthritis by a subcutaneous (s.c.) administration of Freund adjuvant in the posterior right paw and saline in the posterior left paw. The SHAM group was injected with saline in both paws, whereas the control group (CTL) was not submitted to any manipulation. Behavioral tests were carried out twice before induction of arthritis, on the second day of arthritis, and once a week afterwards until the eighth week. Body weight, colonic temperature, and measurements of the injured paw were carried out on the same days. Arthritic rats presented a reduction of total sleep time, increased latency to synchronized sleep, augmented number of episodes of synchronized sleep, reduction of sleep efficiency, more stage shifts, and increased total alert time. Moreover, these animals presented a lower pain threshold than control and SHAM animals. This reduction was observed on the second day of arthritis and remained so reduced until the end of the study. The data appear to indicate a relationship between altered sleep pattern and increased pain sensitivity in arthritic rats.

In 1997 a new prescription system was introduced in the Danish health care system. The pharmacist must now substitute a prescription with a cheaper version of the drug (either generic or original) unless the prescribing doctor indicates that substitution is not allowed in the specific case. The purpose of this study was to evaluate problems of the system and obtain the pharmacists' views on the system. The study was based on questionnaires to a representative sample of 75 pharmacists (a quarter of Denmark's pharmacists). The response rate was 72%. Half of the pharmacists were dissatisfied with the system, which primarily was due to the excessive workload imposed. In spite of this, about half the pharmacists wanted the system to be continued, because the overall purpose of finding the cheapest drug for the patient is good. Nearly all pharmacists thought that analogue substitution (substitution between drugs with the same overall effects but obtained by different means) should not be introduced.

In 1997 a new prescription system was introduced in Denmark. The pharmacist must now substitute the prescribed drug with a cheaper version either by a generic prescription (G-substitution) or by an original prescription (O-substitution) unless the prescribing doctor indicates that substitution is not allowed in the specific case. The purpose of this study was to obtain the patients' view on the new prescription system and to identify any related problems. The investigation was based on structured interviews. The interview guide was designed as a questionnaire, which was validated and tested before use. The response rate was 82%. The study showed that 84% of the patients were satisfied with the system and 85% of the patients thought that it should continue. Eighty-three percent of the patients had tried another version of the substituted medicine earlier. Out of these, 6% had experienced more side-effects from the substituted medicine, and 10% felt that the substituted medicine had a weaker effect. There was one case of erroneous medical treatment as a consequence of the substitution system. Only few problems such as more side-effects or less effect of the substituted medicine was experienced by the patients. It can be concluded that the patients in general are satisfied with the new prescription system.

Among Scandinavian paediatric spinal surgeons there has been a debate whether the prevalence of idiopathic adolescent scoliosis (AIS) has declined. We examined all children in the town of Hillerød, Denmark attending third and fifth grade (age 10 and 12) with forward-bending-test using a scoliometer. All children with more than seven degrees of trunk inclination were referred to a PA radiogram of the spine. We found a 0.4 percent prevalence of AIS with Cobbangles greater than 19 degrees. This is similar to earlier findings, suggesting that the declining referral rate is due to late detection of idiopathic adolescent scoliosis.

A number of potential antioxidants have been evaluated for their effect on formation of radicals in beer using the electron spin resonance (ESR) lag phase method. Sulfite was found to be the only compound that was able to delay the formation of radicals, whereas phenolic compounds such as phenolic acids, catechin, epicatechin, and proanthocyanidin dimers had no effect on the formation of radicals. Ascorbate, cystein, and cysteamin were on the other hand found to be prooxidants. It is suggested that antioxidants must be able to either scavenge peroxides or trap metal ions in order to be effective in beer. The effectiveness of sulfite is suggested to be a consequence of its two-electron nonradical producing reaction with peroxides.

The reactions 204Hg(d, p)205Hg and 204Hg(d, t)203Hg were investigated for Ed = 12–13 MeV, using magnetic spectrographs and photographic detection. Six excited states were observed in 205Hg below 3.6 MeV and thirteen were found in 203Hg below 1.8 MeV. The measured angular distributions were compared with DWBA predictions, and l-values and spectroscopic factors were determined for some of the levels. The data are compared with the corresponding reaction data for the lead nuclei. The nucleus 205Hg appears to have some features in common with 207Pb. In particular, one can identify a 205Hg state at 1.853 MeV which probably corresponds to the 2.73 MeV g92-2h-1p state of 207Pb. The energy systematics of the 12− and 92+ states near 208Pb is discussed in terms of the pairing vibrational model. It is suggested that the change in excitation energy observed between the g92 states of 207Pb and 205Hg is due mainly to the interaction between the proton-hole pair and the neutron-hole pair.

The precise determination of total organic carbon (TOC) in aquifer materials is important in the estimation of retardation coefficients for organic compound transport. Commonly used methods for TOC determination after carbonate removal by acidification include: weight loss on ignition of solids at 550° C, acid-dichromate oxidation, and combustion at 800–950° C. Since carbonate carbon frequently is more abundant than organic carbon all TOC methods depend on efficient and complete carbonate removal prior to the TOC quantification step. A method for the determination of TOC in aquifer solids involving carbonate removal by 0.73 M sulfurous acid and subsequent combustion at 800° C was tested on solids from three aquifers and on mineral standards. The carbon quantification by combustion and infrared detection of CO2 was accurate at solid organic carbon contents between 30 and 10,000 μgC/g. The acid treatment added small amounts of carbon to the sample, and siderite removal was incomplete. For samples without siderite or dolomite, the accuracy of TOC determinations was enhanced by grinding the solids. Measurement of very low TOC contents (50–100 /μgC/g) requires supplementary testing of grinding and acid treatment effects.