Validity of the Suicide Behaviors Questionnaire-Revised in patients with short-term suicide risk

Background and objectives: Suicide is known as a public health problem; however, there are few validated scales with no predictive validity. The aim of this study was to assess the validity of the Spanish version of The Suicidal Behavior Questionnaire-Revised in patients with suicidality. Methods: We applied the Spanish version of The Suicidal Behavior Questionnaire-Revised and 2 other scales to patients with suicide risk. Thirty days later we reassessed to determine the predictive validity for suicide attempt or suicide. Results: 484 patients with suicidality were screened of which 417 were eligible and 411 were evaluable. Factor analysis found a domain with an eigenvalue of 2.0 explaining 50.1% of the variance. With a cutoff point ≥11 the NPV was 98.3% (IC95%, 95.2-99.6) and the PPV was 8.7% (IC95%, 4.7-14.4). Conclusion: The Spanish version of The Suicidal Behavior Questionnaire-Revised, similar to the English version, has moderate internal consistency, adequate concurrent validity and predictive validity

No disponible

Cytological characterization of sunflower by in situ hybridization using homologous rDNA sequences and a BAC clone containing highly represented repetitive retrotransposon-like sequences.

In the present work we report new tools for the characterization of the complete chromosome complement of sunflower (Helianthus annuus L.), using a bacterial artificial chromosome (BAC) clone containing repetitive sequences with similarity to retrotransposons and a homologous rDNA sequence isolated from the sunflower genome as probes for FISH. The rDNA signal was found in 3 pairs of chromosomes, coinciding with the location of satellites. The BAC clone containing highly represented retroelements hybridized with all the chromosome complement in FISH, and used together with the rDNA probe allowed the discrimination of all chromosome pairs of sunflower. Their distinctive distribution pattern suggests that these probes could be useful for karyotype characterization and for chromosome identification. The karyotype could be subdivided into 3 clear-cut groups of 12 metacentric pairs, 1 submetacentric pair, and 4 subtelocentric pairs, thus resolving previously described karyotype controversies. The use of BAC clones containing single sequences of specific markers and (or) genes associated with important agricultural traits represents an important tool for future locus-specific identification and physical mapping.

Conservative management of symptomatic and/or complicated haemorrhoids in pregnancy and the puerperium.

BACKGROUND: Haemorrhoids (piles) are swollen veins at or near the anus, normally asymptomatic. They do not constitute a disease, unless they become symptomatic. Pregnancy and the puerperium predispose to symptomatic haemorrhoids, being the most common ano-rectal disease at these stages. Symptoms are usually mild and transient and include intermittent bleeding from the anus and pain. Depending on the degree of pain, quality of life could be affected, varying from mild discomfort to real difficulty in dealing with the activities of everyday life. Treatment during pregnancy is mainly directed to the relief of symptoms, especially pain control. The so-called conservative management includes dietary modifications, stimulants or depressants of the bowel transit, local treatment, and phlebotonics (drugs that cause decreased capillary fragility, improving the microcirculation in venous insufficiency). For many women, symptoms will resolve spontaneously soon after birth, and so any corrective treatment is usually deferred to some time after birth. Thus, the objective of this review is to evaluate the efficacy of conservative management of piles during pregnancy and the puerperium. OBJECTIVES: To determine the possible benefits, risks and side-effects of the conservative management of symptomatic haemorrhoids during pregnancy and the puerperium. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group Trials Register (30 June 2004). SELECTION CRITERIA: Randomised-controlled trials comparing any of the conservative treatments for symptomatic haemorrhoids during pregnancy and the puerperium (such as dietary modifications, stimulant/depressant of the bowel transit, local treatments, drugs that improve the microcirculation in venous insufficiency) with a placebo or no treatment. DATA COLLECTION AND ANALYSIS: Two review authors independently performed a methodological assessment for deciding which studies to include/exclude from the review and extracted data. MAIN RESULTS: From 10 potentially eligible studies, two were included in this review (150 women). Both compared oral rutosides against placebo. Rutosides seem to be effective in reducing the signs identified by the healthcare provider, and symptoms and signs reported by women, of haemorrhoidal disease. For the outcome no response to treatment: relative risk 0.07, 95% confidence interval 0.03 to 0.20. Regarding perinatal outcomes, one fetal death and one congenital malformation (possible not related to exposure) were reported in the control and treatment group respectively. AUTHORS' CONCLUSIONS: Although the treatment with oral hydroxyethylrutosides looks promising for symptom relief in first and second degree haemorrhoids, its use cannot be recommended until new evidence reassures women and their clinicians about their safety. The most commonly used approaches, such as dietary modifications and local treatments, were not properly evaluated during pregnancy and the puerperium.

Nitration and inactivation of tyrosine hydroxylase by peroxynitrite.

Tyrosine hydroxylase (TH) is modified by nitration after exposure of mice to 1-methyl-4-phenyl-1,2,3,6-tetrahydrophenylpyridine. The temporal association of tyrosine nitration with inactivation of TH activity in vitro suggests that this covalent post-translational modification is responsible for the in vivo loss of TH function (Ara, J., Przedborski, S., Naini, A. B., Jackson-Lewis, V., Trifiletti, R. R., Horwitz, J., and Ischiropoulos, H. (1998) Proc. Natl. Acad. Sci. U. S. A. 95, 7659-7663). Recent data showed that cysteine oxidation rather than tyrosine nitration is responsible for TH inactivation after peroxynitrite exposure in vitro (Kuhn, D. M., Aretha, C. W., and Geddes, T. J. (1999) J. Neurosci. 19, 10289-10294). However, re-examination of the reaction of peroxynitrite with purified TH failed to produce cysteine oxidation but resulted in a concentration-dependent increase in tyrosine nitration and inactivation. Cysteine oxidation is only observed after partial unfolding of the protein. Tyrosine residue 423 and to lesser extent tyrosine residues 428 and 432 are modified by nitration. Mutation of Tyr(423) to Phe resulted in decreased nitration as compared with wild type protein without loss of activity. Stopped-flow experiments reveal a second order rate constant of (3.8 +/- 0.9) x 10(3) m(-1) s(-1) at pH 7.4 and 25 degrees C for the reaction of peroxynitrite with TH. Collectively, the data indicate that peroxynitrite reacts with the metal center of the protein and results primarily in the nitration of tyrosine residue 423, which is responsible for the inactivation of TH.

Reaction of peroxynitrite with Mn-superoxide dismutase. Role of the metal center in decomposition kinetics and nitration.

Manganese superoxide dismutase (Mn-SOD), a critical mitochondrial antioxidant enzyme, becomes inactivated and nitrated in vitro and potentially in vivo by peroxynitrite. Since peroxynitrite readily reacts with transition metal centers, we assessed the role of the manganese ion in the reaction between peroxynitrite and Mn-SOD. Peroxynitrite reacts with human recombinant and Escherichia coli Mn-SOD with a second order rate constant of 1.0 +/- 0.2 x 10(5) and 1.4 +/- 0.2 x 10(5) m(-)1 s(-)1 at pH 7.47 and 37 degrees C, respectively. The E. coli apoenzyme, obtained by removing the manganese ion from the active site, presents a rate constant <10(4) m(-)1 s(-)1 for the reaction with peroxynitrite, whereas that of the manganese-reconstituted apoenzyme (apo/Mn) was comparable to that of the holoenzyme. Peroxynitrite-dependent nitration of 4-hydroxyphenylacetic acid was increased 21% by Mn-SOD. The apo/Mn also promoted nitration, but the apo and the zinc-substituted apoenzyme (apo/Zn) enzymes did not. The extent of tyrosine nitration in the enzyme was also affected by the presence and nature (i.e. manganese or zinc) of the metal center in the active site. For comparative purposes, we also studied the reaction of peroxynitrite with low molecular weight complexes of manganese and zinc with tetrakis-(4-benzoic acid) porphyrin (tbap). Mn(tbap) reacts with peroxynitrite with a rate constant of 6.8 +/- 0.1 x 10(4) m(-)1 s(-)1 and maximally increases nitration yields by 350%. Zn(tbap), on the other hand, affords protection against nitration. Our results indicate that the manganese ion in Mn-SOD plays an important role in the decomposition kinetics of peroxynitrite and in peroxynitrite-dependent nitration of self and remote tyrosine residues.

Synthesis and antitrypanosomal evaluation of E-isomers of 5-nitro-2-furaldehyde and 5-nitrothiophene-2-carboxaldehyde semicarbazone derivatives. structure-activity relationships.

Several novel semicarbazone derivatives were prepared from 5-nitro-2-furaldehyde or 5-nitrothiophene-2-carboxaldehyde and semicarbazides bearing a spermidine-mimetic moiety. All derivatives presented the E-configuration, as determined by NMR-NOE experiments. These compounds were tested in vitro as potential antitrypanosomal agents, and some of them, together with the parent compounds, 5-nitro-2-furaldehyde and 5-nitrothiophene-2-carboxaldehyde semicarbazone derivatives, were also evaluated in vivo using infected mice. Structure-activity relationship studies were carried out using voltammetric response and lipophilic-hydrophilic balance as parameters. Two of the compounds (1 and 3) displayed the highest in vivo activity. A correlation was found between lipophilic-hydrophilic properties and trypanocidal activity, high R(M) values being associated with low in vivo effects.

1,2,5-Oxadiazole N-oxide derivatives and related compounds as potential antitrypanosomal drugs: structure-activity relationships.

The syntheses of a new series of derivatives of 1,2,5-oxadiazole N-oxide, benzo[1,2-c]1,2,5-oxadiazole N-oxide, and quinoxaline di-N-oxide are described. In vitro antitrypanosomal activity of these compounds was tested against epimastigote forms of Trypanosoma cruzi. For the most effective drugs, derivatives IIIe and IIIf, the 50% inhibitory dose (ID50) was determined as well as their cytotoxicity against mammalian fibroblasts. Electrochemical studies and ESR spectroscopy show that the highest activities observed are associated with the facile monoelectronation of the N-oxide moiety. Lipophilic-hydrophilic balance of the compounds could also play an important role in their effectiveness as antichagasic drugs.

Synthesis and anti-trypanosomal activity of novel 5-nitro-2-furaldehyde and 5-nitrothiophene-2-carboxaldehyde semicarbazone derivatives.

Several novel semicarbazones derivatives were prepared from 5-nitro-2-furaldehyde or 5-nitrothiophene-2-carboxaldehyde, and tested in vitro as potential anti-trypanosomal agents. The compounds were prepared in good to excellent yields in 2-3 steps from readily available starting materials. Some derivatives were found to be active against Trypanosoma cruzi with an activity similar to that of Nifurtimox.

Cytogenetically aberrant cells are present in the CD34+CD33-38-19- marrow compartment in children with acute lymphoblastic leukemia.

Acute lymphoblastic leukemia (ALL), the most common cancer in childhood, is characterized by clonal proliferation of transformed lymphoblasts that comprise the majority of marrow and/or blood specimens. Although the leukemic cells typically express antigens associated with lymphoid maturation or activation (ie CD19, CD38, etc), it has been suggested that ALL blasts may evolve from a more primitive precursor. Increased understanding of the phenotypic and molecular heterogeneity of cells in ALL may provide clues to leukemogenesis and/ or impact prognostication or treatment. We utilized a phenotype/genotype approach to measure the prevalence and frequency of cytogenetically aberrant cells in a phenotypically defined primitive compartment (CD34+33-19-38-; CD34+Lin-). Bone marrow cells were flow cytometrically sorted into CD34-Lin+, CD34+Lin+ and CD34+Lin- subpopulations. Fluorescence in situ hybridization (FISH) was used to quantify the frequency of cells with aneusomies in the sorted populations. Approximately 26% (5/19) of ALL cases at diagnosis contain cytogenetically aberrant CD34+Lin- cells. The frequency of cytogenetically aberrant cells in the CD34+Lin- compartment is independent of FAB, WBC and blast counts. These data indicate that cytogenetically aberrant cells may reside in a phenotypically defined primitive subpopulation and suggest that ALL blasts in some patients may evolve from a precursor compartment.

Pathways of peroxynitrite oxidation of thiol groups.

Peroxynitrite mediates the oxidation of the thiol group of both cysteine and glutathione. This process is associated with oxygen consumption. At acidic pH and a cysteine/peroxynitrite molar ratio of < or = 1.2, there was a single fast phase of oxygen consumption, which increased with increasing concentrations of both cysteine and oxygen. At higher molar ratios the profile of oxygen consumption became biphasic, with a fast phase (phase I) that decreased with increasing cysteine concentration, followed by a slow phase (phase II) whose rate of oxygen consumption increased with increasing cysteine concentration. Oxygen consumption in phase I was inhibited by desferrioxamine and 5,5-dimethyl-1-pyrroline N-oxide, but not by mannitol; superoxide dismutase also inhibited oxygen consumption in phase I, while catalase added during phase II decreased the rate of oxygen consumption. For both cysteine and glutathione, oxygen consumption in phase I was maximal at neutral to acidic pH: in contrast, total thiol oxidation was maximal at alkaline pH. EPR spin-trapping studies using N-tert-butyl-alpha-phenylnitrone indicated that the yield of thiyl radical adducts had a pH profile comparable with that found for oxygen consumption. The apparent second-order rate constants for the reactions of peroxynitrite with cysteine and glutathione were 1290 +/- 30 M-1.S-1 and 281 +/- 6 M-1.S-1 respectively at pH 5.75 and 37 degrees C. These results are consistent with two different pathways participating in the reaction of peroxynitrite with low-molecular-mass thiols: (a) the reaction of the peroxynitrite anion with the protonated thiol group, in a second-order process likely to involve a two-electron oxidation, and (b) the reaction of peroxynitrous acid, or a secondary species derived from it, with the thiolate in a one-electron transfer process that yields thiyl radicals capable of initiating an oxygen-dependent radical chain reaction.

Partial cognitive-dysmnesic seizures as a model for studying psychosis.

Nineteen patients were analyzed who exhibited cognitive-dysmnesic psychic partial seizures and structural damage shown by means of CT scans. It was observed that these seizures originated in the amygdala-hippocampal system, coinciding with the effects found when using electrical stimulation of the brain. An attempt is made to relate these findings to the present biochemical hypotheses of schizophrenia, the kindling effect and the genetico-maturational hypotheses. All these data seem to agree and point in the direction of the possible neurophysiological mechanisms of psychosis and of schizophrenia in particular.

Isolation of serologically active HLA-A, B, C and DR antigens as monitored by a fixed cell radioimmunoassay.

Procedures for isolation of antigenically active preparations of human HLA antigens were monitored using a sensitive and quantitative radioimmunoassay for HLA-A, B, C or HLA-DR antigens. These assays involve binding of radiolabeled monoclonal antibodies to appropriate target cells and inhibition of this binding by solubilized antigen preparations. Fixation of the target cells with glutaraldehyde allows quantitation of inhibitors in high concentrations of nonionic detergents. Using this assay, it was possible to examine quantitatively the relative merits of several alternative procedures for isolating both class I and class II antigens. For example, chromatography of cell lysates on columns of Ricinus communis agglutinin gave high recoveries of DR antigens purified from the majority of cell proteins. When Lens culinaris hemagglutinin was used for separation of cell lysates approximately 90% of the A, B, C antigens but only 32% of the DR antigens bound the column and were eluted by alpha-methyl-mannoside. Immunoadsorbent column were then used to recover antigenically active molecules suitable for structural or functional studies from these enriched fractions.