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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 204: 125-130, 2018 Nov 05.
Article in English | MEDLINE | ID: mdl-29920415

ABSTRACT

The photo-bleaching reaction of the chemical actinometer, Aberchrome 540™, is reported for the first time in a series of ionic liquids (ILs). This fulgide in its C-form undergoes an opening reaction to yield its E-form, when it is irradiated with UV light at wavelengths >400 nm. The magnitude of bleaching was monitored spectrophotometrically and their kinetics evaluated, obtaining first-order rate constants (kobs). The results obtained in different ILs suggest that changes in the rate constants (kobs) of the opening reaction of Aberchrome 540™ are mainly governed by weaker interactions such as coulombic (π* parameter) and Van der Waals interactions (δH2, parameter). In addition, the photochemical fatigue resistance was also studied in ILs media and compared with conventional solvents (benzene, toluene, etc.). In particular, we found that three different tendencies dependent on the ILs used exist. The first group of ILs where the reversibility of the fulgide is favored (for example, [Bmim][BF4], [Bmim][PF6] and [Bmim][OTf]), behaviour similar to conventional solvents. The second group corresponds to ILs where photo reversibility is partial; and finally, other group of ILs that prevented photo reversibility. It is proposed that depending on the ILs used, the stabilization of different forms of the fulgide can be controlled, thus resulting important in terms of choosing the appropriate ILs for a specific photochemical reaction.

2.
Photochem Photobiol ; 75(6): 585-90, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12081319

ABSTRACT

The effect of Boldo and black tea infusions on the pro-oxidant effects of vitamin B2, riboflavin (RF), when exposed to the action of visible light was studied. The amounts of antioxidants present in Boldo and tea infusions were evaluated by a procedure based on the bleaching of preformed 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cations and were expressed as 6-hydroxy-2,5,7,8-tetramethyl-chroman-2-carboxylic acid equivalent concentrations. The quenching rate constants of singlet oxygen (1O2; [kq]Boldo = 6.0 x 10(7) M(-1) s(-1) and [kq]Tea = 3.2 x 10(7) M(-1) s(-1)) and triplet RF (3RF; [3RFkq]Boldo = 10 x 10(8) M(-1) s(-1) and [3RFkq]TEA = 3.2 x 10(8) M(-1) s(-1)) with Boldo and tea were determined by flash photolysis. These data allow a quantitative interpretation of the results obtained. Our data suggest that most of the oxygen consumption observed in the photolysis of RF in the presence of tea and Boldo infusions is caused by 1O2 reactions. The oxygen consumption quantum yield is considerably smaller than the fraction of RF triplets trapped by the additives (AH) present in the infusion, indicating that their interaction with 3RF does not lead to chemical reactions or that the AH*+ radical ions initially formed participate in secondary processes that do not consume oxygen. Boldo and tea infusions have a significant protective effect when a system containing RF and tryptophan (Trp) is exposed to visible light, not only by quenching the 1O2 and interfering with the Type-I mechanism but also by repairing the damage to Trp molecules associated with the latter mechanism.


Subject(s)
Riboflavin/radiation effects , Tea/physiology , Chromans/chemistry , Kinetics , Light , Oxidants , Riboflavin/chemistry , Singlet Oxygen
3.
Int J Neuropsychopharmacol ; 4(3): 269-72, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11602033

ABSTRACT

The hypothesis implicating the serotonergic system in the pathophysiology of obsessive-compulsive disorder (OCD) is supported by the therapeutic efficacy of selective serotonin reuptake inhibitors (SSRIs). Since SSRIs act on the serotonin transporter (5-HTT), it has been suggested that the 5-HTT gene (SCL6A4) could be a good candidate for OCD. The SCL6A4 gene has a 44-bp insertion/deletion polymorphism in its promoter region (5-HTTLPR). Previous studies have revealed an association between OCD and the l allele. We analysed the 5-HTTLPR polymorphic system in 115 Mexican OCD patients and 136 controls. No significant association was found between l allele and OCD (chi2 = 1.54, d.f. = 1, p = 0.21). Furthermore, we assessed alternative methods that employ family-based designs in a sample of 43 trios. Haplotype-based haplotype relative risk and transmission disequilibrium analysis did not show a preferential transmission of l allele to OCD probands. Our results indicate the need to analyse larger samples using family-based methods.


Subject(s)
Carrier Proteins/genetics , Carrier Proteins/metabolism , Membrane Glycoproteins/genetics , Membrane Glycoproteins/metabolism , Membrane Transport Proteins , Nerve Tissue Proteins , Obsessive-Compulsive Disorder/genetics , Obsessive-Compulsive Disorder/metabolism , Adult , Alleles , Female , Genotype , Humans , Male , Mexico , Polymorphism, Genetic , Promoter Regions, Genetic/genetics , Serotonin Plasma Membrane Transport Proteins
4.
J Nat Prod ; 64(6): 783-6, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11421743

ABSTRACT

Five new withanolides, 5 alpha,6 alpha:22,26:24,25-triepoxy-16 alpha,26-dihydroxy-18(13-->17)-abeo-ergosta-2,13-dien-1-one (salpichrolide N, 1), 5 alpha,6 alpha:22,26:24,25-triepoxi-15 alpha,26-dihydroxyergosta-2,16-dien-1-one (salpichrolide L, 2), 5 alpha,6 alpha:22,26-diepoxi-24,25,26-trihydroxy-17(13-->18)-abeo-ergosta-2,13,15,17-tetraen-1-one (salpichrolide M, 3a), 5 alpha,6 alpha:22,25:22,26-triepoxy-24-hydroxy-17(13-->18)-abeo-ergosta-2,13,15,17-tetraen-1-one (salpichrolide J, 4), and 5 alpha,6 alpha:22,26-diepoxy-22,24,25-trihydroxy-17(13-->18)-abeo-ergosta-2,13,15,17-tetraen-1-one (salpichrolide K, 5), were isolated from the leaves of Salpichroa origanifolia and characterized by a combination of spectroscopic (1D and 2D NMR, MS) and chemical methods.


Subject(s)
Ergosterol/analogs & derivatives , Ergosterol/isolation & purification , Plants, Medicinal/chemistry , Argentina , Magnetic Resonance Spectroscopy , Mass Spectrometry
5.
Am J Med Genet ; 105(3): 279-82, 2001 Apr 08.
Article in English | MEDLINE | ID: mdl-11353450

ABSTRACT

Studies have recently reported a sexually dimorphic association between obsessive-compulsive disorder (OCD) and a polymorphism related with variations in MAO-A activity. These observations suggest the possibility of gender differences in genetic susceptibility for OCD. We thus reexamined the MAO-A/EcoRV polymorphism in a sample of 122 OCD patients and 124 healthy subjects. An excess of allele 1 in OCD females with major depression disorder was confirmed as previously reported. This difference was more strongly associated with OCD females than males in the total sample. Finally, we analyzed a sample of 51 OCD trios. Haplotype-based haplotype relative risk (HHRR) analysis of the inheritance of the MAO-A variants revealed in the female probands that 14 out of 19 transmitted the allele 1, providing significant evidence for an allelic association between OCD and MAO-A gene. In conclusion, our findings may provide molecular evidence to identify a clinically meaningful gender subtype. However, an effort should be made to replicate the analysis in larger samples of informative parents using strategies such as transmission disequilibrium test to allow definite conclusions.


Subject(s)
Genetic Variation/genetics , Monoamine Oxidase/genetics , Obsessive-Compulsive Disorder/genetics , Adult , Alleles , Case-Control Studies , Chi-Square Distribution , Female , Genetic Predisposition to Disease , Haplotypes , Humans , Male , Middle Aged , Obsessive-Compulsive Disorder/etiology , Polymorphism, Genetic , Sex Factors
6.
J Org Chem ; 65(23): 7949-58, 2000 11 17.
Article in English | MEDLINE | ID: mdl-11073603

ABSTRACT

The photophysical and photochemical behavior of 1-methyl-3-phenylquinoxalin-2-one (MeNQ) and 3-phenylquinoxalin-2-one (HNQ) in the presence of amines is reported. While HNQ fluorescence shows an auxochromic effect and a bathochromic shift with added amines, explained by association of HNQ with amine in the ground state and emission from both excited species HNQ and [HNQ-amine], both MeNQ and HNQ are photoreduced efficiently on irradiation in the presence of amines, leading to the semireduced quinoxalin-2-ones, MeNQH(-) and HNQH(-), respectively, via an electron-proton-electron transfer, with unit quantum yields at high amine concentrations. The semireduced quinoxalin-2-ones XNQH(-) (X = H, Me) revert almost quantitatively to the parent XNQ in a dark thermal reaction with an activation free energy for MeNQH(-) of 17.4 and 25.9 kcal/mol in acetonitrile and benzene, respectively. Kinetic and spectroscopic (UV and NMR) evidence supports the proposed reaction mechanism for the reversible photoreduction.

7.
Life Sci ; 66(26): 2509-18, 2000 May 19.
Article in English | MEDLINE | ID: mdl-10883729

ABSTRACT

The pseudoguaianolide sesquiterpene lactones 4-alpha-O-acetyl-pseudoguaian-6beta-olide (1), hymenin (2), ambrosanolide (3), tetraneurin A (4), parthenin (5), hysterin (6) and confertdiolide (7) were evaluated for their ability to affect the inflammation responses induced by different agents. All the compounds showed activity against the 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced mouse ear edema. The ethyl phenylpropiolate (EPP)-induced mouse ear edema was inhibited by compounds 3, 5 and 7. However, when sesquiterpene-lactones were assayed on the arachidonic acid (AA)-induced mouse ear edema, none of them were active. The only sesquiterpene lactone orally active against the paw mouse edema induced by carrageenan was 7, which gave a 46% edema inhibition after 3 h. On the other hand, compounds 3, 5 and 7 reduced the serotonin-induced paw edema in mice, although compound 7 was inactive in presence of cycloheximide. In addition, the sesquiterpene lactones were assayed against the chronic inflammation induced by repeated application of TPA on mouse ear. Confertdiolide was the most active compound; it reduced the edema by 87% and had a more moderate effect against the leukocyte recruitment (36% reduction in myeloperoxidase (MPO) levels). A histological study of ear the samples treated with 7 presented no detectable morphological lesions such as those treated with dexamethasone. On the oxazolone-induced delayed type hypersensitivity (DTH) only compounds 4 and 5 were active 24 h after the challenge. Compound 5 affected polymorphonuclear leukocyte infiltration (69% reduction in MPO levels). The results suggest that the especial chemical structure and spatial conformation of confertdiolide may facilitate its anti-inflammatory effect.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Inflammation/drug therapy , Sesquiterpenes/pharmacology , Acute Disease , Animals , Anti-Inflammatory Agents, Non-Steroidal/isolation & purification , Chronic Disease , Female , Inflammation/chemically induced , Mice , Plants/chemistry , Sesquiterpenes/isolation & purification , Tetradecanoylphorbol Acetate/antagonists & inhibitors , Tetradecanoylphorbol Acetate/pharmacology
8.
Phytochemistry ; 55(7): 769-72, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11190393

ABSTRACT

A population of Parthenium hysterophorus collected in Salta Argentina afforded two ambrosanolides, 2beta-hydroxycoronopilin and 1alpha,2beta,4beta-trihydroxypseudoguaian-6beta,12-olide, as well as five known others. Plants of the fructification from those transplanted from the Puna Argentina at 1200 m over the sea level produced hymenin.


Subject(s)
Asteraceae/chemistry , Lactones/chemistry , Sesquiterpenes/chemistry , Spectrum Analysis
10.
Recent Dev Alcohol ; 14: 383-96, 1998.
Article in English | MEDLINE | ID: mdl-9751955

ABSTRACT

This chapter describes the development of the Alcohol Use Disorders Identification Test (AUDIT) among various Mexican populations, the evaluations that followed the World Health Organization international research project from where this screening instrument was derived, its use in nonclinical settings, modifications introduced in its wording, the development of a short version, and validity and reliability tests. It also describes rates of hazardous, harmful, and dependent drinkers and biobehavioral consequences of abuse among various Mexican populations. Data drawn from different samples showed adequate levels of specificity and sensitivity. Findings from general population samples confirmed previous observations in general practice: That the AUDIT could capture not only regular consumption at hazardous levels, but also episodic heavy drinking. Data from an International Labor Office/World Health Organization project on model programs for alcohol prevention in the workplace showed that it was possible to derive a short version, easily used for intervention programs, that differentiated categories of drinkers at various risk levels. Rates of problem drinkers in clinical samples varied between 28 and 43% for males and 3.6 and 4.8% among females. Hazardous drinking varied between 0.7 and 15.5% among males and females in general populations and reached 44% in a sample of male workers; in clinical settings, harmful drinking ranged from 7 to 16% among males and dependence from 3 to 10%.


Subject(s)
Alcoholism/diagnosis , Cross-Cultural Comparison , Mass Screening , Personality Inventory , Adult , Aged , Alcoholism/epidemiology , Cross-Sectional Studies , Female , Humans , Incidence , Male , Mexico/epidemiology , Middle Aged , Patient Care Team , Psychometrics , Reproducibility of Results
11.
J Appl Toxicol ; 18(1): 15-8, 1998.
Article in English | MEDLINE | ID: mdl-9526829

ABSTRACT

Differences in ethanol pharmacokinetics within the menstrual cycle have previously been reported and attributed to variations in body composition, hormonal influences and gastric emptying. To establish the role of the menstrual cycle in ethanol pharmacokinetics associated with changes in body composition, ethanol blood concentrations were measured in nine healthy women during the midfollicular (P1, days 8-10) and midluteal (P2, days 22-24) phases of the menstrual cycle after a postprandial oral ethanol dose (0.3 g kg(-1)). Total body water was assessed by dual-energy x-ray densitometry (DEXA) on both occasions. Median total body water did not vary during either phase of the menstrual cycle (P1 = 54.54%, P2 = 54.66%; P = 0.9296). Median area under the ethanol concentration-time curve (AUC) was lower during P1 (215.33 mg.h dl(-1)) than during P2 (231.33 mg.h dl(-1))(P = 0.8253). No significant differences were found on ethanol pharmacokinetics in either phase of the menstrual cycle.


Subject(s)
Ethanol/pharmacokinetics , Menstrual Cycle/blood , Administration, Oral , Adult , Area Under Curve , Body Composition , Body Water , Ethanol/administration & dosage , Ethanol/blood , Female , Follicular Phase/blood , Humans , Liver Function Tests , Luteal Phase/blood , Mexico
12.
Neurosci Lett ; 231(1): 1-4, 1997 Aug 01.
Article in English | MEDLINE | ID: mdl-9280153

ABSTRACT

The polymorphism characterized by a varying number of 48 bp repeats (VNTR) in the dopamine D4 receptor (DRD4) gene was examined in 61 obsessive-compulsive disorder (OCD) probands with and without tics. Most of the OCD patients with tics showed at least one copy of the 7-fold variant compared to those affected subjects without tics (91 vs. 48%, respectively, Yates corrected chi2 = 5.54, P = 0.018). Similarly, a higher number of copies of this common variant were detected in the group of probands displaying tics compared to those OCD's without tics (Yates corrected chi2 = 4.66, P = 0.03). Our study suggests that the seven-repeat allele of the DRD4 gene could be a factor in the phenotypic variance of tics among OCD individuals.


Subject(s)
Obsessive-Compulsive Disorder/genetics , Receptors, Dopamine D2/genetics , Repetitive Sequences, Nucleic Acid , Tic Disorders/genetics , Alleles , DNA/analysis , Family Health , Female , Gene Frequency , Genotype , Humans , Male , Receptors, Dopamine D4 , Tourette Syndrome/genetics
14.
Mol Psychiatry ; 1(6): 461-5, 1996 Dec.
Article in English | MEDLINE | ID: mdl-9154247

ABSTRACT

We performed an association analysis of the DRD2, DRD3 and 5HT2A genes polymorphisms in 67 Obsessive-Compulsive Disorder (OCD) patients and 54 healthy controls. There were no statistically significant differences in genotype or allele frequencies for any of the polymorphisms studied between OCD subjects and controls. For the subgrouped analysis, no results were significant after correction for multiple testing, although homozygosity of DRD2/A2A2 in subjects displaying vocal or motor tics approached significance compared to controls (Fisher exact test, P = 0.008). Our results may follow the notion that OCD patients with tics represent a different genetic subtype of the disease.


Subject(s)
Obsessive-Compulsive Disorder/genetics , Polymorphism, Genetic , Receptors, Dopamine D2/genetics , Receptors, Serotonin/genetics , Adolescent , Adult , Aged , Brain Chemistry/genetics , Cloning, Molecular , Female , Genetic Linkage , Genotype , Humans , Male , Middle Aged , Polymorphism, Restriction Fragment Length , Receptor, Serotonin, 5-HT2A , Receptors, Dopamine D3
15.
Psychopharmacology (Berl) ; 121(4): 476-9, 1995 Oct.
Article in English | MEDLINE | ID: mdl-8619011

ABSTRACT

The role of nicotine as an indirect cholinergic agent in sleep has been studied in normal subjects. There are no studies of its effects on sleep in depressed patients. Nicotine transdermal patches (17.5 mg), were studied in eight depressed patients (DSM-III-R) and eight normal volunteers. Subjects wore placebo and nicotine patches for 24 h. Depressed patients showed increased REM sleep without changes in other sleep variables. They also showed a short term improvement of mood. Normal volunteers had sleep fragmentation, and reduction of REM sleep time. No major side effects were reported in either group.


Subject(s)
Affect/drug effects , Depressive Disorder/drug therapy , Nicotine/therapeutic use , Sleep/drug effects , Adult , Analysis of Variance , Female , Humans , Male , Middle Aged
18.
Addiction ; 88(6): 791-804, 1993 Jun.
Article in English | MEDLINE | ID: mdl-8329970

ABSTRACT

The Alcohol Use Disorders Identification Test (AUDIT) has been developed from a six-country WHO collaborative project as a screening instrument for hazardous and harmful alcohol consumption. It is a 10-item questionnaire which covers the domains of alcohol consumption, drinking behaviour, and alcohol-related problems. Questions were selected from a 150-item assessment schedule (which was administered to 1888 persons attending representative primary health care facilities) on the basis of their representativeness for these conceptual domains and their perceived usefulness for intervention. Responses to each question are scored from 0 to 4, giving a maximum possible score of 40. Among those diagnosed as having hazardous or harmful alcohol use, 92% had an AUDIT score of 8 or more, and 94% of those with non-hazardous consumption had a score of less than 8. AUDIT provides a simple method of early detection of hazardous and harmful alcohol use in primary health care settings and is the first instrument of its type to be derived on the basis of a cross-national study.


Subject(s)
Alcoholism/prevention & control , Cross-Cultural Comparison , Mass Screening , World Health Organization , Alcoholism/classification , Alcoholism/genetics , Humans , Personality Assessment/statistics & numerical data , Psychometrics , Reference Standards , Risk Factors
19.
Acta Psiquiatr Psicol Am Lat ; 39(1): 45-9, 1993 Mar.
Article in Spanish | MEDLINE | ID: mdl-8237432

ABSTRACT

This paper describes the procedure to obtain some DNA probes likely to be good candidate genes for mapping major psychiatric disorders. The advantages in using this mapping strategy are discussed as well.


Subject(s)
Chromosome Mapping/methods , DNA Probes , Mental Disorders/genetics , Cloning, Molecular , DNA Restriction Enzymes , Electrophoresis, Agar Gel , Humans , Molecular Weight , Plasmids/isolation & purification
20.
Acta Psiquiatr. Psicol. Am. Lat ; 39(1): 45-9, 1993 Mar.
Article in Spanish | BINACIS | ID: bin-37820

ABSTRACT

This paper describes the procedure to obtain some DNA probes likely to be good candidate genes for mapping major psychiatric disorders. The advantages in using this mapping strategy are discussed as well.

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