Ultrasonic irradiation as a tool to modify the H-desorption from hydrides: MgH(2) suspended in decane

Effects of ultrasonic irradiation on magnesium hydride (MgH(2)) suspended in decane were investigated with the purpose of improving its hydrogen desorption process. Firstly, we have found that the presence of MgH(2) improves the sonolysis of decane enhancing the amount of hydrogen evolved during the sonication process. The sonicated-MgH(2) maintains its microstructural properties practically unaltered but a drastic reduction of the particle size of MgH(2) (down to approximately 20mum) as well as a high pressure MgH(2) phase are observed. However, no substantial modifications of H-kinetic properties of hydride occur as is determined by thermal desorption measurements. This could be attributed to decomposition of decane during sonication which leads to the formation of carbon compounds that hinder the thermal decomposition of MgH(2).

[Analysis of the literature on the relatives of the critical patient: research in effective care needs to be performed]

AIM

To explore the nature of studies on families and the Intensive Care Unit context and the issues they deal with.

DESIGN AND METHODS

This is a qualitative, methodological study that makes a documental analysis of 24 articles (between 1993-2004) located by descriptors in journals and databases. A double analysis was conducted: quality assessment and content analysis.

RESULTS

The articles analyzed were mainly descriptive and reviews of the literature. Six categories were found: environment hostility, family needs, design of interventions, nursing care, experience of the families, and decision making autonomy.

CONCLUSIONS

The nursing staff wants to establish care aimed at the patient's family. To do so, they need to be trained in psychological aspects such as handling of emotional stress, strategies and skills for coping and communication strategies and skills. Research should change its focus from being description to proposing and evaluating intervention strategies. Research findings should translate into recommendations for this change.

Growth and laccase production by Pleurotus ostreatus in submerged and solid-state fermentation

Pleurotus ostreatus showed atypical laccase production in submerged vs. solid-state fermentation. Cultures grown in submerged fermentation produced laccase at 13,000 U l(-1), with a biomass production of 5.6 g l(-1) and four laccase isoforms. However, cultures grown in solid-state fermentation had a much lower laccase activity of 2,430 U l(-1), biomass production of 4.5 g l(-1), and three laccase isoforms. These results show that P. ostreatus performs much better in submerged fermentation than in solid-state fermentation. This is the first report that shows such atypical behavior in the production of extracellular laccases by fungi.

Determination of bile acids in human serum by on-line restricted access material-ultra high-performance liquid chromatography-mass spectrometry

This paper describes a new, fully automated on-line method combining restricted access material (RAM) extraction and ultra high-performance liquid chromatography (UHPLC) with mass spectrometric (MS) detection for determining congeners of bile acids (BAs) in human serum. In this method, low-pressure RAM and high-pressure UHPLC-MS are hyphenated by using a 2.5-mL loop-type interface. The compatibility problem between the large volume (1.2mL) of strong solvent (methanol) used for RAM elution and the need for a weak solvent in UHPLC injection has been addressed by using an auxiliary pre-column cross-flow of 0.1% aqueous formic acid. In this way, the complete 2.5mL loop volume can be injected into the UHPLC system, thereby maximizing sensitivity while maintaining good chromatographic performance. The optimised method allows the simultaneous analysis of 13 bile acids in a single run, including glycine- and taurine-conjugated bile acids, cholic acid (CA), deoxycholic acid (DCA), chenodeoxycholic acid (CDCA), ursodeoxycholic acid (UDCA), and litocholic acid. The complete analysis of a 100-microL single serum sample is performed in 30 min, providing detection limits in the pg range (corresponding with clinically relevant concentration levels) for all of the analytes except lithocholic acid, intra-day precision values (%R.S.D.) below 4% (except ursodeoxycholic acid) and inter-day precision lower than 15% (except ursodeoxycholic, glycoursodeoxycholic acid (GUDCA) and lithocholic acid).

Cardiovascular risk factor management is poorer in diabetic patients with undiagnosed peripheral arterial disease than in those with known coronary heart disease or cerebrovascular disease. Results of a nationwide study in tertiary diabetes centres

AIMS

To assess whether patients with Type 2 diabetes mellitus and unrecognized peripheral arterial disease (PAD), detected by the ankle-brachial index (ABI), have poorer cardiovascular risk factor management (CVRFs) and receive fewer medications than patients previously diagnosed with coronary heart disease (CHD) or cerebrovascular disease (CVD).

METHODS

In 31 diabetes centres throughout Spain, 1303 patients with Type 2 diabetes mellitus were screened for PAD using the ABI. Patient history of CHD and CVD and treatment and control of CVRFs were recorded.

RESULTS

Forty-one patients had an ABI > 1.30 and were excluded, leaving 1262 patients (age 65.3 +/- 7.7 years) for the study. Of those screened, 790 patients had a normal ABI (ABI > 0.9) and no known history of CHD or CVD (no CHD/CVD/PAD group), 194 had unrecognized PAD (ABI < or = 0.9) with no known history of CHD or CVD (undiagnosed PAD group) and 278 had a known history of CHD and/or CVD (CHD/CVD group). The undiagnosed PAD group had higher low-density lipoprotein (LDL) cholesterol (2.9 +/- 0.83 vs. 2.4 +/- 0.84 mmol/l; P < 0.001) and systolic blood pressure (150 +/- 20 vs. 145 +/- 21 mmHg; P < 0.001) compared with the CHD/CVD group. They were less likely to take statins (56.9 vs. 71.6%; P < 0.001), anti-hypertensive agents (75.9 vs. 90.1%, P = 0.001), and anti-platelet agents (aspirin, 28.7 vs. 57.2%; P < 0.001; clopidogrel, 5.6 vs. 20.9%; P < 0.001) and more likely to smoke (21.0 vs. 9.2%; P < 0.001). Higher LDL in the undiagnosed PAD group was associated with the underutilization of statins.

CONCLUSIONS

Measurement of ABI detected a significant number of patients with PAD, who did not have CHD or CVD, but whose CVRFs were under treated and poorly controlled compared with subjects with CHD and/or CVD.

Epicrania fugax: an ultrabrief paroxysmal epicranial pain

Ten patients (one man and nine women, mean age 48.8 +/- 20.1) presented with a stereotypical and undescribed type of head pain. They complained of strictly unilateral, shooting pain paroxysms starting in a focal area of the posterior parietal or temporal region and rapidly spreading forward to the ipsilateral eye (n = 7) or nose (n = 3) along a lineal or zigzag trajectory, the complete sequence lasting 1-10 s. Two patients had ipsilateral lacrimation, and one had rhinorrhoea at the end of the attacks. The attacks could be either spontaneous or triggered by touch on the stemming area (n = 2), which could otherwise remain tender or slightly painful between the paroxysms (n = 5). The frequency ranged from two attacks per month to countless attacks per day, and the temporal pattern was either remitting (n = 5) or chronic (n = 5). This clinical picture might be a variant of an established headache or represent a novel syndrome.

[Escitalopram: a selective inhibitor and allosteric modulator of the serotonin transporter]

Citalopram (Séropram) is an antidepressant of the selective serotonin (5-HT) reuptake inhibitor (SSRI) class, composed of equal amounts of S-enantiomer, escitalopram, and R-enantiomer, R-citalopram. Both clinical and preclinical studies have reported that escitalopram is a potent SSRI that possesses a faster onset of antidepressant activity in comparison with citalopram. Conversely, R-citalopram, although devoid of 5-HT reuptake inhibition property, was reported to counteract the effect of the S-enantiomer in several in vitro and in vivo experiments. For instance, microdialysis studies have shown that escitalopram increased the extracellular 5-HT levels in the frontal cortex and the ventral hippocampus, and this effect was prevented by concomitant injection of R-citalopram. The in vivo relevance of the antagonistic effect of R-citalopram on escitalopram efficacy was confirmed in dorsal raphe nucleus, a brain region known to be a target for SSRIs. In the later region, escitalopram was four times more potent than citalopram in suppressing the firing activity of 5-HT neurons and this effect of escitalopram was significantly prevented by R-citalopram. The antagonizing effect of R-citalopram on escitalopram efficacy was also observed in behavioural tests predictive of anxiolytic or antidepressant properties. In adult rats, R-citalopram reduced the anxiolytic-like effect of escitalopram obtained in the footshock-induced ultrasonic vocalization model, the conditioned fear model or the Vogel conflict and elevated plus maze tests. In validated chronic models with high predictive value for antidepressant activity, when escitalopram was administered for five weeks, either alone or with twice as much R-citalopram, the effect of the treatment regimens on reversal of hedonic deficit was significantly different. Importantly, chronic treatment with escitalopram reversed the decrease in cytogenesis in the rat dentate gyrus, induced by chronic mild stress. However, in naïve rats, while chronic treatment with R-citalopram did not modify the basal proliferation rate in the dentate gyrus, it blocked the increase induced by escitalopram when coadministered. This suggests that neuronal adaptive changes, which are essential for antidepressant response, are rapidly induced by escitalopram but prevented by R-citalopram coadministration. The attenuating effect of R-citalopram was suggested to underlie the delayed recovery of 5-HT neuronal activity following long-term treatment with citalopram versus escitalopram. This is confirmed since a treatment with R-citalopram antagonized the recovery of firing observed in escitalopram-treated rats. The exact mechanism by which R-citalopram exerts its action is not yet fully defined; however, an allosteric interaction between the enantiomers and the 5-HT transporter (SERT) has been proposed. In this context, in vitro studies have revealed the existence of at least two binding sites on SERT: (1) a primary high-affinity binding site or orthosteric site that mediates the inhibition of 5-HT reuptake and (2) an allosteric low-affinity binding site that modulates the binding of ligands at the primary site. In presence of escitalopram alone, both the primary and the allosteric sites are occupied. Thus, escitalopram exerts a stabilizing effect on this association to SERT, resulting in an effective inhibition of 5-HT reuptake activity. On the other hand, in the presence of the two enantiomers, R-citalopram binds to the allosteric site and decreases the escitalopram action on SERT. Such an innovative mechanism of action can constitute a basis for development of new allosteric antidepressants that demonstrate higher efficacy and earlier onset of therapeutic effect.

[Vitamin B complex and homocysteine in chronic renal failure]

Metabolic, biochemical, and hormonal changes occur in chronic renal failure usually associated with hyponutrition states. In predialysis patients, knowing the nutritional state about water-soluble vitamins such as thiamine, riboflavin, pyridoxine, cianocobalamine, and folic acid is becoming more and more important since some of the manifestations of chronic renal failure may be due to the deficiency of some of these water-soluble vitamins. The metabolic pathways in which most of these vitamins participate are interrelated and it is difficult to understand how the individual deficits of each vitamin affect renal pathology. This work aims at reviewing not only this issue but also the status of these water-soluble vitamins that different authors have found in groups of predialysis patients. On the other hand, the issue on the high prevalence of hyperhomocysteinemia in chronic renal failure as the main mortality risk factor due to cardiovascular pathologies as well as the implication of these vitamins in the metabolism of homocysteine, and consequently in plasma levels of this metabolite in predialysis patients is reviewed.

Development of flexible antimicrobial films using essential oils as active agents

The antimicrobial activity in the vapor-phase of laboratory-made flexible films of polypropylene (PP) and polyethylene/ethylene vinyl alcohol copolymer (PE/EVOH) incorporating essential oil of cinnamon ( Cinnamomum zeylanicum), oregano ( Origanum vulgare), clove ( Syzygium aromaticum), or cinnamon fortified with cinnamaldehyde was evaluated against a wide range of microorganisms: the Gram-negative bacteria Escherichia coli, Yersinia enterocolitica, Pseudomonas aeruginosa, and Salmonella choleraesuis; the Gram-positive bacteria Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, and Enterococcus faecalis; the molds Penicillium islandicum, Penicillium roqueforti, Penicillium nalgiovense, Eurotium repens, and A spergillus flavus and the yeasts Candida albicans, Debaryomyces hansenii, and Zigosaccharomyces rouxii. Films with a nominal concentration of 4% (w/w) of fortified cinnamon or oregano essential oil completely inhibited the growth of the fungi; higher concentrations were required to inhibit the Gram-positive bacteria (8 and 10%, respectively), and higher concentrations still were necessary to inhibit the Gram-negative bacteria. PP films were more effective than PE/EVOH films. The atmospheres generated by the antimicrobial films inside Petri dishes were quantitatively analyzed using headspace-single drop microextraction (HS-SDME) in combination with gas chromatography-mass spectrometry (GC-MS). The analyses showed that the oregano-fortified PP films released higher levels of carvacrol and thymol, and the cinnamon-fortified PP films released higher levels of cinnamaldehyde, during the first 3-6 h of incubation, than the corresponding PE/EVOH films. Shelf-life tests were also performed, demonstrating that the antifungal activities of the films persisted for more than two months after their manufacture. In addition, migration tests (overall and specific) were performed, using both aqueous and fatty simulants, to ensure that the films meet EU regulations regarding food contact materials. Following contact with the tested films, the substances that had migrated into the aqueous simulants were recovered by direct immersion-single drop extraction (DI-SDME) and then analyzed by GC-MS. The fatty stimulant (isooctane) was directly injected into the chromatographic system.

R-citalopram prevents the neuronal adaptive changes induced by escitalopram

This study examined the long-term effects of the antidepressant escitalopram on rat serotonin (5-HT) neuronal activity and hippocampal neuroplasticity. In the dorsal raphe nucleus, a 2-week treatment with escitalopram (10 mg/kg/day, subcutaneous) did not modify the firing activity of 5-HT neurons, whereas a cotreatment with R-citalopram (20 mg/kg/day, subcutaneous) decreased it. In the dentate gyrus of dorsal hippocampus, escitalopram increased significantly (57%) the number of de novo cells and this was prevented by a cotreatment with R-citalopram. The present results support the role of the allosteric modulation of the 5-HT transporter in the regulation of the recovery of 5-HT neuronal activity and long-lasting hippocampal cellular plasticity induced by escitalopram, two adaptive changes presumably associated with the antidepressant response.

Haplotype frequencies of 16 Y-chromosome STR loci in the Barcelona metropolitan area population using Y-Filer™ kit

Haplotype frequencies for 16 Y-chromosomal short tandem repeat (STR) loci, included in the Y-Filer kit, were determined in 247 unrelated healthy individuals from the Barcelona metropolitan area (Catalonia, NE Spain). After PCR amplification and denaturing PAGE electrophoresis, DYS456, DYS389I, DYS390, DYS389II, DYS458, DYS19, DYS385a/b, DYS393, DYS391, DYS439, DYS635, DYS392, Y GATA H4.1, DYS437, DYS438 and DYS448 loci were typed. The aim of this study is to evaluate the performance in our population of the 16 loci of the Y-chromosome present in the new Y-Filer commercial identification kit, and acquire haplotype frequencies for mathematic processing of the forensic diagnosis in our geographical working area. In this sample, all haplotypes were unique. From the forensic point of view, the combined polymorphisms of the Y-Filer kit provide a high diagnostic efficiency.

Prevalence of Dementia Subtypes in El Prat de Llobregat, Catalonia, Spain: The PRATICON Study

BACKGROUND

Studies on dementia subtypes show a wide variation in the prevalence of Alzheimer's disease (AD) and vascular dementia (VD) worldwide. However, studies reporting on Lewy body dementia (LBD) and frontotemporal dementia (FTD) are sparse.

AIMS

To describe the prevalence of dementia and subtypes.

METHOD

A 34% sample of 5,150 subjects aged 70 years and over in El Prat de Llobregat (Barcelona) were screened by the Mini-Mental State Examination. When scoring <24, participants were assessed to establish a diagnosis.

RESULTS

There were 165 subjects diagnosed with dementia (prevalence of 9.4%). Subtypes of dementia were: AD 69.1%, VD 12.7%, LBD 9.1%, FTD 3% and secondary dementia 1.8%. Prevalences were: AD 6.5%, VD 1.2%, LBD 0.9% and FTD 0.3%.

CONCLUSIONS

AD and VD were the most common type of dementia. Prevalence of dementia, AD and FTD were similar to those reported, while prevalence of VD and LBD were lower.

Lack of generalisation between the GABAA receptor agonist, gaboxadol, and allosteric modulators of the benzodiazepine binding site in the rat drug discrimination procedure

INTRODUCTION

The binding sites for gamma-aminobutyric acid (GABA) and GABA(A) receptor agonists are located differently from the binding sites for benzodiazepine receptor agonists. Furthermore, the major pharmacological effects of benzodiazepine receptor agonists and the GABA(A) receptor agonist gaboxadol (4,5,6,7-tetrahydrroisoxazolo(5,4-c)pyridin-3-ol, THIP) are mediated by different GABA(A) receptor subunit compositions; that is, gaboxadol may interact primarily with extra-synaptically located alpha(4)beta(2/3)delta-containing receptors and benzodiazepines with the synaptically located alpha(1)beta(2/3)gamma(2)-containing receptors.

OBJECTIVES

The aim of the present study was to address if this different receptor subtype selectivity was reflected in vivo.

MATERIALS AND METHODS

A two-lever liquid reinforced operant discrimination procedure was conducted. Three groups of rats were trained to discriminate gaboxadol, diazepam and zolpidem 5.5, 1.5 and 0.7 mg/kg i.p., respectively, from vehicle.

RESULTS

Substitution tests showed that gaboxadol-trained animals failed to recognize diazepam (0.75-1.5 mg/kg), zolpidem (0.4-0.7 mg/kg), zopiclone (2.5 mg/kg), zaleplon (1.0-1.5 mg/kg) or indiplon (0.31 mg/kg). In contrast, all benzodiazepine receptor agonists, but not gaboxadol (4.5-5.5 mg/kg), generalised to the discriminative stimulus in diazepam- and zolpidem-trained animals.

DISCUSSION

In agreement with these data, the competitive benzodiazepine receptor antagonist flumazenil (10 mg/kg s.c.) antagonised the discriminative stimulus of zolpidem but not of gaboxadol. Interaction tests showed no synergistic interaction of concomitant administration of gaboxadol and zolpidem or diazepam.

CONCLUSION

Previous studies have shown that gaboxadol and benzodiazepines interact with different receptor populations, and the present study confirms that in vivo functional consequences of this receptor selectivity exist in the form of differential behavioural responses in rats.

Measurement of sigma chi c2 B(chi c2-->J/psi gamma)/sigma chi c1 B(chi c1 -->J/psi gamma) in pp collisions at square root s=1.96 TeV

We measure the ratio of cross section times branching fraction, Rp=sigma chi c2 B(chi c2-->J/psi gamma)/sigma chi c1 B(chi c1-->J/psi gamma), in 1.1 fb(-1) of pp collisions at square root s=1.96 TeV. This measurement covers the kinematic range pT(J/psi)>4.0 GeV/c, |eta(J/psi)<1.0, and pT(gamma)>1.0 GeV/c. For events due to prompt processes, we find Rp=0.395+/-0.016(stat)+/-0.015(syst). This result represents a significant improvement in precision over previous measurements of prompt chi c1,2 hadro production.

Inclusive search for new physics with like-sign dilepton events in pp collisions at square root of s =1.96 TeV

We describe a search for anomalous production of events with two leptons (e or mu) of the same electric charge in pp[over ] collisions at a center-of-mass energy of 1.96 TeV. Many extensions to the standard model predict the production of two leptons of the same electric charge. This search has a significant increase in sensitivity compared to earlier searches. Using a data sample corresponding to 1 fb(-1) of integrated luminosity recorded by the CDF II detector, we observe no significant excess in an inclusive selection (expect 33.2+/-4.7 events, observe 44) or in a supersymmetry-optimized selection (expect 7.8+/-1.1 events, observe 13.).

Data for Y-chromosome haplotypes in Fang and Bubi populations from Bioko (Equatorial Guinea)

Haplotype frequencies for 16 Y-chromosomal short tandem repeat (DYS456, DYS389I, DYS390, DYS389II, DYS458, DYS19, DYS385a/b, DYS393, DYS391, DYS439, DYS635, DYS392, Y GATA H4, DYS437, DYS438 and DYS448) loci, included in the AmpFLSTR Yfiler PCR Amplification Kit, were analysed in 110 Fang and 133 Bubi individuals from Bioko Island, Equatorial Guinea. The diversity was higher in Fang population, probably since they were originally from the mainland, with which they maintain tribal village and family links, and to which they travel frequently. Comparisons were made with previously published haplotype data on European and African populations, and significant differences were found between them.