Amiodarone inhibits thyroidal iodide transport in vitro by a cyclic adenosine 5'-monophosphate- and iodine-independent mechanism

Thyroid side effects are common in patients treated for cardiac arrhythmias with amiodarone (AM). A major disturbance is inhibited thyroidal radioiodine uptake in AM-induced thyrotoxicosis, which makes 131I therapy ineffective. On the other hand, failure to escape from the Wolff-Chaikoff effect by down-regulation of the sodium/iodide symporter (NIS) is proposed to explain AM-induced hypothyroidism. However, previously no experimental studies on the possible mechanisms have been conducted. We therefore investigated the early effects of AM on thyroidal iodide transport using bicameral chamber cultures of primary pig thyrocytes that reproduce the three tissue compartments (epithelium, lumen, and extrafollicular space) of the gland. AM dose-dependently (1-50 microm) inhibited the TSH-stimulated transepithelial (basal to apical) transport of 125I- by up to 90%. The inhibitory effect was noticed already after 8 h and was further pronounced after 1-4 d, depending on the AM concentration. The intracellularly accumulated 125I- was reduced by perchlorate but not AM, and quantitative real-time RT-PCR revealed no change in the NIS expression in AM-treated cells. Blocking of cAMP degradation with 3-isobutyl-1-methylxanthine or withdrawal of AM reversed AM-induced changes in electrolyte transport but were unable to recover the suppressed 125I- transport. The iodine-free AM analog dronedarone also inhibited 125I- transport to the same extent as AM. The findings indicate that AM blocks thyroidal iodide uptake by reducing the iodide permeability of the apical plasma membrane of the thyroid epithelial cells. The effect is iodine independent and long-lasting and does not involve impaired function of NIS or the TSH receptor/cAMP signaling pathway.

Improving pulse sequences for 3D diffusion-ordered NMR spectroscopy: 2DJ-IDOSY

An improved pulse sequence for the 3D DOSY experiment 2DJ-DOSY, using diffusion encoding internal to the parent 2DJ spectroscopy sequence (2DJ-IDOSY), is presented. The diffusion-encoding pulses are used to enforce the desired coherence transfer pathway, reducing the minimum experimental time by at least a factor of 4, as compared to existing techniques, and approximately doubling the signal-to-noise ratio for small molecules. The new sequence is demonstrated on a simple mixture and on a complex sample with a high dynamic range (port wine). The principle of internal diffusion encoding can be applied with profit to a range of other 3D DOSY experiments.

Perception of very small visual stimuli in the fovea: normative data for the Rarebit Foveal Test

BACKGROUND

Conventional visual tests are not sensitive enough to detect low degree neural damage, as 6/6 (1.0) visual acuity can be upheld with less than two-thirds of the normal number of optic nerve axons. The aim of the current study was to evaluate the physiologic properties of a new computerised test, the Rarebit Fovea Test (RFT), using very small stimuli, by quantifying the effect of age and binocular summation in relation to stimulus luminance.

METHODS

The RFT relies on the perception of very small (less than 0.5 minutes of arc) bright stimuli. Two different experiments were performed. 1. Thirty-five subjects (age 19 to 63 years) were tested with five different stimulus luminances, 158, 64, 53, 41 and 33 cd/m(2). 2. Nineteen subjects (age 19 to 63 years) were tested using binocular stimulation to define the binocular summation.

RESULTS

Significantly reduced median hit rates were observed at luminances of 53 cd/m(2) or below. Age and mean hit rate correlated negatively at all luminance levels below 158 cd/m(2). The mean hit rate from binocular stimulation, compared to the highest value from monocular stimulation in the same subject, was increased by a factor of 1.54 +/- 0.45 (SD). No age effect was found regarding binocular summation.

CONCLUSIONS

The results in the current study indicate that RFT can identify some of the well-known features of the visual system, that is, the effects of age and binocular summation, provided that the stimulus luminance is adequately selected.

Cell swelling, seizures and spreading depression: an impedance study

The cellular processes that take place during the transition from pre-seizure state to seizure remain to be defined. In this study in awake, paralyzed rats, we used an electrical impedance measure of changes in extra-cellular intracranial volume to estimate changes in cell size in acute models of epilepsy. Animals were prepared with extradural electroencephalographic (EEG)/impedance electrodes and a venous catheter. On a subsequent day, animals were paralyzed, ventilated and treated with picrotoxin, kainic acid or fluorocitrate in doses that usually induce epileptiform discharges. We now report that increases in baseline impedance were induced by kainic acid and smaller increases by picrotoxin. We also demonstrated that epileptiform discharges were preceded by small, accelerated increases in impedance. Increases in baseline impedance were highly correlated with increases in power of non-ictal high frequency EEG activity. Seizures were accompanied by increases in impedance and all treatments induced transient, relatively large, increases in impedance often associated with unilateral reductions in low frequency EEG, likely periods of spreading depression. We conclude: cerebral cells swell in convulsant models of epilepsy, that there are pre-ictal accelerations in cell swelling, and that spreading depression-like events are frequently associated with seizures.

Biexponential Fitting of Diffusion-Ordered NMR Data: Practicalities and Limitations

High resolution diffusion-ordered NMR spectroscopy (HR-DOSY) generally uses monoexponential fitting of the diffusional attenuation of pulsed-field gradient stimulated echo spectra and can, thus, only give proper separation of signals in the diffusion domain where the individual peaks are well-resolved in the spectral domain. In principle, it should be possible to resolve the decays of coincident spectral peaks by multiexponential fitting, but the well-known fundamental difficulties in such a separation are exacerbated by instrumental distortions of the signal decay. The limitations imposed on biexponential fitting by finite signal-to-noise ratio and by the distortion of the theoretical form of the signal attenuation as a result of pulsed-field gradient nonuniformity are explored, and the improvement in DOSY spectra produced using biexponential fitting afforded by compensating for the latter are illustrated.

ImmunoCAP Phadiatop Infant--a new blood test for detecting IgE sensitisation in children at 2 years of age

BACKGROUND

Correct diagnosis of immunoglobulin E (IgE)-mediated disease is the prerequisite for secondary allergy prevention during early childhood.

OBJECTIVE

To evaluate the diagnostic efficacy of a new blood test, Phadiatop Infant, in detecting IgE sensitisation to food and inhalant allergens among children at 2 years of age.

METHODS

Children (n = 239) were followed prospectively from birth to 2 years of age for the presence of IgE sensitisation and the development of atopic manifestations. Immunoglobulin E sensitisation was evaluated by skin prick test (SPT) and analysis of allergen-specific IgE antibodies in plasma to food and inhalant allergens. The children were classified into three groups: IgE-sensitised, non-IgE sensitised and inconclusive, depending on SPT and allergen-specific IgE results.

RESULTS

Twenty-six (11%) of the children were classified as IgE-sensitised, 182 (76%) as non-IgE sensitised and 31 (13%) as inconclusive. Phadiatop Infant was positive in 50 (21%) of the children. Ten children (4%) with identified IgE antibodies against the selected food and inhalant allergens showed negative Phadiatop Infant. Three children showed positive Phadiatop Infant but were negative in the other tests performed. These results correspond to positive and negative predictive values for Phadiatop Infant of 89 and 99%, respectively. Children with clinical symptoms of atopic diseases had significantly increased levels for Phadiatop Infant (P < 0.01).

CONCLUSION

Phadiatop Infant appears to be a reliable alternative to SPT and the measurement of allergen-specific IgE antibodies in plasma for detecting clinically important IgE sensitisation among children at 2 years of age.

Truncation and fusion of HMGA2 in lipomas with rearrangements of 5q32-->q33 and 12q14-->q15

Chromosome segment 12q13-->q15 recombines with many different chromosome bands in lipomas and at least ten recurrent translocations have been identified. The HMGA2 gene is often rearranged, but little is known about the molecular consequences at other breakpoints. Fusion genes between HMGA2 (12q14-->q15) and LPP (3q27-->q28), LHFP (13q12) and CMKOR1 (2q37) have been reported. In the present study, eight lipomas with rearrangements involving chromosome bands 12q14-->q15 and 5q32-->q33 were analyzed. In chromosome 5, five of the cases had a breakpoint in the 5' part of EBF in 5q33, while three cases had breakpoints located about 200 kb 3' of EBF. In chromosome 12, the breakpoints clustered to the region of HMGA2. Four cases had breaks within the gene and four had breaks 5' to HMGA2 where the gene BC058822 is located. Two versions of an HMGA2/EBF fusion transcript were detected in one case; one transcript was in frame and the other out of frame. Identical EBF/BC058822 fusion transcripts, seen in two cases, one of which also had the HMGA2/EBF transcript, were out of frame and resulted in truncation of EBF. Since EBF and HMGA2 have different orientations, the findings must be explained by complex aberrations including multiple breaks. The combined data indicate that the pathogenetically significant event is fusion, truncation or transcriptional activation of HMGA2, but it can not be excluded that EBF, which has been implicated in adipogenesis, contributes to the tumor development.

Quantification of mtDNA mixtures in forensic evidence material using pyrosequencing

Analysis of mtDNA variation using Sanger sequencing does not allow accurate quantification of the components of mtDNA mixtures. An alternative method to determine the specific mixture ratios in samples displaying hetero-plasma, consisting of DNA contributions from several individuals, or containing contamination would therefore be valuable. A novel quantification system for mtDNA mixture analysis has been developed based on pyrosequencing technology, in which the linear relationship between incorporated nucleotides and released light allows quantification of the components of a sample. Within five polymerase chain reaction fragments, seven variable positions in the mtDNA control and coding region were evaluated using this quantification analysis. For all single nucleotide polymorphisms quantified in this study, a linear relationship was observed between the measured and expected mixture ratios. This mtDNA quantification assay is an easy to use, fast and accurate quantification system, with the ability to resolve and interpret major and minor mtDNA components in forensic mixture samples.

Reactive astrogliosis induces astrocytic differentiation of adult neural stem/progenitor cells in vitro

Neural stem cells reside in defined areas of the adult mammalian brain, including the dentate gyrus of the hippocampus. Rat neural stem/progenitor cells (NSPCs) isolated from this region retain their multipotency in vitro and in vivo after grafting into the adult brain. Recent studies have shown that endogenous or grafted NSPCs are activated after an injury and migrate toward lesioned areas. In these areas, reactive astrocytes are present and secrete numerous molecules and growth factors; however, it is not currently known whether reactive astrocytes can influence the lineage selection of NSPCs. We investigated whether reactive astrocytes could affect the differentiation, proliferation, and survival of adult NSPCs by modelling astrogliosis in vitro, using mechanical lesion of primary astrocytes. Initially, it was found that conditioned medium from lesioned astrocytes induced astrocytic differentiation of NSPCs without affecting neuronal or oligodendrocytic differentiation. In addition, NSPCs in coculture with lesioned astrocytes also displayed increased astrocytic differentiation and some of these NSPC-derived astrocytes participated in glial scar formation in vitro. When proliferation and survival of NSPCs were analyzed, no differential effects were observed between lesioned and nonlesioned astrocytes. To investigate the molecular mechanisms of the astrocyte-inducing activity, the expression of two potent inducers of astroglial differentiation, ciliary neurotrophic factor and leukemia inhibitory factor, was analyzed by Western blot and shown to be up-regulated in conditioned medium from lesioned astrocytes. These results demonstrate that lesioned astrocytes can induce astroglial differentiation of NSPCs and provide a mechanism for astroglial differentiation of these cells following brain injury.

Rapid decrease of free vancomycin in dense staphylococcal cultures

Bacterial numbers in broth cultures were determined by bioluminescence assay of intracellular bacterial ATP. Broth MICs for strains of Staphylococcus epidermidis (ATCC 14990 and 35984) and Staphylococcus aureus (ATCC 25923, 29213 and 6538) were determined for cultures with different inocula (10(5)-10(8) bacteria/ml) after 24 h of incubation in supplemented Mueller-Hinton broth containing vancomycin. All of the tested strains except one were susceptible to methicillin, and all of the strains were susceptible to vancomycin. Free vancomycin concentrations in the broth cultures of all strains were determined with an agar well bioassay after 24 h of incubation. Free vancomycin concentrations and bacterial numbers of ATCC 35984 and ATCC 29213 were also determined after 0.5, 2, 4, and 8 h. In a low inoculum (10(5) bacteria/ml), the broth MICs were 1-4 microg/ml. In a high inoculum (approximately 10(8) bacteria/ml), the broth MICs increased two- to fourfold to 4-8 microg/ml. In dense inocula ( approximately 10(9)-10(10) bacteria/ml), the concentrations of free vancomycin in the broth were reduced, in most cases below the detection limit of the bioassay (</=0.5 microg/ml). This reduction of free vancomycin was fast, occurring in initially dense inocula in less than 30 min. No emergence of resistance was seen. These results show a rapid reduction of free vancomycin in the broth and a simultaneous increase in broth MICs in high inocula, without development of resistance. This indicates that the dosing regimen of vancomycin is of particular importance in staphylococcal infections with dense inocula, e.g. infective endocarditis.

Improving pulse sequences for 3D DOSY: convection compensation

Signal overlap in the NMR dimension significantly complicates the construction and analysis of 2D diffusion-ordered (DOSY) spectra. Such problems can often be reduced or even eliminated by extending the NMR domain of a DOSY experiment into two dimensions, giving a 3D-DOSY spectrum. To date such experiments have generally sacrificed some signal-to-noise ratio and have required extensive and time-consuming phase cycling. A new family of pulse sequences with internal diffusion encoding (IDOSY) has been introduced which avoids both of these problems. It is often straightforward to incorporate convection compensation in such sequences at no cost in signal-to-noise ratio. Here, some of the problems caused by convection in DOSY are described and illustrated, and the efficacy of convection compensation in the 2DJ-IDOSY and COSY-IDOSY experiments is demonstrated.

Dissociation in a polymerization model of homochirality

A fully self-contained model of homochirality is presented that contains the effects of both polymerization and dissociation. The dissociation fragments are assumed to replenish the substrate from which new monomers can grow and undergo new polymerization. The mean length of isotactic polymers is found to grow slowly with the normalized total number of corresponding building blocks. Alternatively, if one assumes that the dissociation fragments themselves can polymerize further, then this corresponds to a strong source of short polymers, and an unrealistically short average length of only 3. By contrast, without dissociation, isotactic polymers becomes infinitely long.

Glucose and insulin responses to porridge and gruel meals intended for infants

OBJECTIVE

The objective was to determine the glycaemic index (GI) and insulinaemic index (II) of some common products intended for infants; that is, three commercial porridges and one gruel. Also, the influence of added fruit components to porridge on postprandial metabolic responses was studied by comparing corresponding data with a matched model product without fruit.

DESIGN

The volunteers were served the test products in random order following an overnight fast. A white bread was included as a reference product. Capillary blood samples were collected before and during 3 h after the meals.

SETTING

The study was performed at the Department of Applied Nutrition and Food Chemistry, Lund University, Sweden.

SUBJECTS

A total of 10 healthy volunteers, six men and four women, aged 24-41 y, with normal body mass indices, were recruited.

RESULTS

The GIs (67-75) of the commercial porridges and gruel were significantly lower than for the white bread reference (P < 0.05). In contrast, the GI (79) of the model product (porridge without fruit) could not be distinguished from the reference. The IIs (112-149) for the commercial products and model products, respectively, were not significantly different from the reference.

CONCLUSIONS

: The commercial porridges and gruel gave unexpectedly low GIs. In contrast, high IIs were noted. The inconsistency between GI and II could probably be explained by the insulinotrophic effect of the milk component in the products. The fruit and fruit juice added to some of the products had only minor effect on postprandial glycaemia.

SPONSORSHIP

The Swedish Council for Forestry and Agricultural Research.

Fusion of the HMGA2 and NFIB genes in lipoma

The major cytogenetic subgroup of lipomas is characterized by aberrations of chromosome segment 12q13-15, which recombines with a large number of other chromosomal regions. The gene HMGA2 is the main target in these aberrations. For some recurrent rearrangements, chimeric transcripts, including the 5' part of HMGA2, have been described. The 3' partners identified are LPP, LHFP, CMKOR1, and EBF. In addition, subsets of other benign solid tumors show aberrations of 12q13-15. Among pleomorphic adenomas of the salivary glands, where the preferred recombination partner with 12q13-15 is 9p22-24, an HMGA2/NFIB fusion gene has been reported. In the present study, two cases of lipoma with rearrangements of 9p22-24 and 12q15 were analyzed by reverse transcription polymerase chain reaction to find out if HMGA2/NFIB was also present in lipoma. An in-frame fusion transcript, combining the four first exons of HMGA2 with exon 8 of NFIB, was detected in one case. It was identical to a transcript that was previously described in salivary gland adenoma and contained a stop codon shortly 3' of the fusion point. The finding of the same fusion gene in different tumors is not unique. For example, HMGA2/LPP has been reported in lipoma, pulmonary chondroid hamartoma, and soft tissue chondroma. Since similar 9;12 translocations have been described also in rare cases of hamartoma and uterine leiomyoma, the occurrence of HMGA2/NFIB could be postulated in these tumors as well.

Medical intelligence in Sweden. Vitamin B12: oral compared with parenteral?

BACKGROUND

Sweden is the only country in which oral high dose vitamin B12 has gained widespread use in the treatment of deficiency states.

OBJECTIVE

The aim of the study was to describe prescribing patterns and sales statistics of vitamin B12 tablets and injections in Sweden 1990-2000.Design, setting, and sources: Official statistics of cobalamin prescriptions and sales were used.

RESULTS

The use of vitamin B12 increased in Sweden 1990-2000, mainly because of an increase in the use of oral high dose vitamin B12 therapy. The experience, in statistical terms a "total investigation", comprised 1,000,000 patient years for tablets and 750,000 patient years for injections. During 2000, 13% of residents aged 70 and over were treated with vitamin B12, two of three with the tablet preparation. Most patients in Sweden requiring vitamin B12 therapy have transferred from parenteral to oral high dose vitamin B12 since 1964, when the oral preparation was introduced.

CONCLUSION

The findings suggest that many patients in other post-industrial societies may also be suitable for oral vitamin B12 treatment.

Homochiral growth through enantiomeric cross-inhibition

The stability and conservation properties of a recently proposed polymerization model are studied. The achiral (racemic) solution is linearly unstable once the relevant control parameter (here the fidelity of the catalyst) exceeds a critical value. The growth rate is calculated for different fidelity parameters and cross-inhibition rates. A chirality parameter is defined and shown to be conserved by the nonlinear terms of the model. Finally, a truncated version of the model is used to derive a set of two ordinary differential equations and it is argued that these equations are more realistic than those used in earlier models of that form.

Mitochondrial glutathione: a modulator of brain cell death

The small fraction of glutathione in mitochondria in nonneural tissues is an important contributor to cell survival under some conditions. However, there has been only limited characterization of the properties and function of mitochondrial glutathione in cells from the brain. In astrocytes in culture, highly selective depletion of this glutathione pool does not affect cell viability, at least in the first 24 h, but does greatly increase susceptibility to exposure to nitric oxide or peroxynitrite. In vivo, a selective partial loss of glutathione develops during focal cerebral ischemia and persists during reperfusion. The timing and distribution of glutathione loss shows an apparent association with the likelihood that tissue infarction will subsequently develop. Furthermore, infarct volume is greatly decreased by intracerebroventricular infusion of glutathione monoethylester, a compound that can increase mitochondrial glutathione. Together these recent findings indicate that alterations in mitochondrial glutathione are likely to contribute to the severity of tissue damage in stroke and possibly other neurological disorders. Thus, this antioxidant pool provides a potentially useful target for therapeutic intervention.

Improving pulse sequences for 3D DOSY: COSY-IDOSY

An improved pulse sequence for measuring diffusion-ordered COSY spectra is achieved by incorporating the diffusion encoding directly into the evolution and detection periods of a gradient-enhanced COSY sequence, giving improved sensitivity and a 32-fold reduction in minimum experiment time.

Lifestyle related risk factors in the aetiology of gastro-oesophageal reflux

BACKGROUND/AIM

The aetiology of gastro-oesophageal reflux is largely unknown. The authors' aim was to examine the relation between lifestyle habits and gastro-oesophageal reflux symptoms.

SUBJECTS

Participants of two consecutive public health surveys in Nord-Trondelag, Norway.

METHODS

In a case control study within the two public health surveys, 3153 individuals who in the second survey reported severe heartburn or regurgitation during the last 12 months were defined as cases, while 40 210 people without reflux symptoms constituted the control group. The risk of reflux symptoms was estimated and multivariately calculated as odds ratios in relation to exposure to tobacco smoking, alcohol, coffee, tea, table salt, cereal fibres, and physical exercise.

RESULTS

There was a significant dose response association between tobacco smoking and reflux symptoms. Among people who had smoked daily for more than 20 years the odds ratio was 1.7 (95% confidence interval 1.5 to 1.9) compared with non-smokers. A similar positive association was found for table salt intake. The odds ratio for reflux was 1.7 (95% CI 1.4 to 2.0) among those who always used extra table salt compared with those who never did so. We found moderately strong negative associations between the risk of reflux and exposure to coffee, bread high in dietary fibre content, and frequent physical exercise. Intake of alcohol or tea did not affect the risk of reflux.

CONCLUSIONS

Tobacco smoking and table salt intake seem to be risk factors for gastro-oesophageal reflux symptoms. Dietary fibres and physical exercise may protect against reflux. Alcohol, coffee, and tea do not seem to be risk factors for reflux.

Prevalence of gastro-oesophageal reflux symptoms and the influence of age and sex

BACKGROUND

Most previous studies of reflux symptom prevalence are of small sample size. No reliable data concerning age- and sex-stratified prevalence are available.

METHODS

Among 65,363 adult participants in a public health survey in Nord-Trondelag, Norway, 58,596 (90%) responded concerning occurrence and severity of heartburn or regurgitation during the past 12 months. The prevalence of minor, severe and any reflux symptoms was calculated, including stratification for age and sex. In order to examine whether the relative risk of reflux symptoms between sexes, in different age groups, was affected by other potential risk factors for reflux, confounding effects were tested using multivariate logistic regression. Odds ratios and their 95% confidence intervals were used to estimate relative risks.

RESULTS

Total prevalence of reflux symptoms was 31.4%, whereof 26.0% were minor symptoms and 5.4% severe symptoms. The prevalence of symptoms occurring at least weekly was 11.6%. Among women, the prevalence increased gradually from 22.1% in the youngest age category to 37.5% in the oldest, while among men it gradually increased from 25.8% in the youngest age group to peak at 36.0% between the ages of 50 and 60 years, after which it declined to 33.8% after age 70. A higher prevalence among women compared to men in the oldest age groups was not explained by confounding by body mass, tobacco smoking, alcohol consumption, dietary factors, or physical exercise.

CONCLUSIONS

About every third adult person suffered from reflux symptoms. The prevalence increases linearly with age among women, while among men it peaked between the age of 50 and 70 years and thereafter declined.

Localised astroglial dysfunction disrupts high-frequency EEG rhythms

We used cerebral cortex injections of fluorocitrate to determine if selective astrocytic disturbances affect the electroencephalogram (EEG). Rats were halothane-anaesthetized and 0.8 nmol of sodium fluorocitrate was injected into hindlimb (motor-sensory) cortex. Extra-dural EEG electrodes were implanted after which the anaesthesia was ceased. EEG was recorded at 1, 3, 5, 7, 24 and 48 hours. There was a broad-band reduction in frequencies in the EEG between 20 and 100 Hz commencing within 1 hour of injection and largely restricted to the side of injection and to frontal cortex, and maximal at 3 hours. Halothane had a suppressive effect on gamma power after citrate injection, but also prevented EEG suppression caused by fluorocitrate, consistent with the hypothesis that some of the action of fluorocitrate depended on gap-junctions. The findings are consistent with the hypothesis that primary astroglial dysfunction leads to reduced neuronal transmission and further supports gap-junctions as mediating fluorocitrate-induced astroglial effects.

TSH receptor signaling via cyclic AMP inhibits cell surface degradation and internalization of E-cadherin in pig thyroid epithelium

Incorporation of E-cadherin into the adherens junction is a highly regulated process required to establish firm cell-cell adhesion in most epithelia. Less is known about the mechanisms that govern the clearance of E-cadherin from the cell surface in both normal and pathological states. In this study, we found that the steady-state removal of E-cadherin in primary cultured pig thyroid cell monolayers is slow and involves intracellular degradation. Experimental abrogation of adhesion by a Ca2+ switch induces rapid cell surface proteolysis of E-cadherin. At the same time, endocytosed intact E-cadherin and newly synthesized E-cadherin accumulate in intracellular compartments that largely escape further degradation. Acute stimulation with thyroid-stimulating hormone (TSH) or forskolin prevents all signs of accelerated E-cadherin turnover. The findings indicate that TSH receptor signaling via cyclic AMP stabilizes the assembly and retention of E-cadherin at the cell surface. This suggests a new mechanism by which TSH supports maintenance of thyroid follicular integrity.

High-resolution NMR and diffusion-ordered spectroscopy of port wine

The use of high-resolution NMR and high-resolution diffusion-ordered spectroscopy (DOSY) for the characterization of selected Port wine samples of different ages with the aim of identifying changes in composition is described. Conventional 1D and 2D NMR methods enabled the identification of about 35 compounds, including minor components such as some medium-chain alcohols, amino acids, and organic acids. High-resolution (HR) DOSY extended sample characterization, increasing the number of compounds identified and NMR assignments made, by providing information on the relative molecular sizes of the metabolites present. Port wines of different ages were found to differ mainly in their content of (a) organic acids and some amino acids, (b) an unidentified possible disaccharide, and (c) large aromatic species. The relative amount of these last high Mw aromatics is seen to decrease significantly in the oldest wine, as expected from the known formation and precipitation of anthocyanin-based polymers during red wine aging.

Gene expression profiling identifies liver X receptor alpha as an estrogen-regulated gene in mouse adipose tissue

Estrogens reduce adipose tissue mass in both humans and animals. The molecular mechanisms for this effect are, however, not well characterized. We took a gene expression profiling approach to study the direct effects of estrogen on mouse white adipose tissue (WAT). Female ovariectomized mice were treated for 10, 24 and 48 h with 17beta-estradiol or vehicle. RNA was extracted from gonadal fat and hybridized to Affymetrix MG-U74Av2 arrays. 17beta-Estradiol was shown to decrease mRNA expression of liver X receptor (LXR) alpha after 10 h of treatment compared with the vehicle control. The expression of several LXRalpha target genes, such as sterol regulatory element-binding protein 1c, apolipoprotein E, phospholipid transfer protein, ATP-binding cassette A1 and ATP-binding cassette G1, was similarly decreased. We furthermore identified a 1.5 kb LXRalpha promoter fragment that is negatively regulated by estrogen. Several genes involved in lipogenesis and lipolysis were identified as novel targets that could mediate estrogenic effects on adipose tissue. Finally, we show that ERalpha is the main estrogen receptor expressed in mouse white adipose tissue (WAT) with mRNA levels several hundred times higher than those of ERbeta mRNA.

Schizophrenia: From Dopamine to Glutamate and Back

The first part of the present review describes the exciting journey of dopamine stabilizers, starting in the early eighties with the development of the partial dopamine agonist (-)-3-PPP of phenylpiperidine structure, via various compounds with aminotetraline structure with preferential autoreceptor antagonist properties, and then back again to phenylpiperidine compounds carrying substituents on the aromatic ring that transformed them from partial dopamine agonists to partial dopamine receptor antagonists, such as OSU6162. OSU6162 was brought to the clinic and has in preliminary trials showed antidyskinetic and antipsychotic efficacy. The second part of this review describes results from a hypoglutamatergia mouse model for cognitive symptoms of schizophrenia, where we have tested traditional neuroleptics, new generation antipsychotics with marked 5-HT2 vs dopamine D2 receptor blockade as well as a dopamine stabilizer belonging to the partial dopamine receptor antagonist category.