Positive emotional induction interferes with the reconsolidation of negative autobiographical memories, in women only.

After reactivation, a previously consolidated memory can enter into a labile state followed by a re-stabilization process defined as reconsolidation. The aim of this study was to explore whether an existing negative autobiographical memory can be modified by using a non-invasive interference (audiovisual positive preparation) after reactivation and to determine if this effect could be dependent on the reconsolidation process. We found that the presentation of a positive inductor after a negative autobiographical memory reactivation may lead to a change in the emotional information of the original trace and that such effect can be mediated by the reconsolidation process. The modification of the memory has been shown in women only. These results suggest that a positive audiovisual induction may play a potential role in psychotherapeutic techniques for the modification of dysfunctional autobiographical memories.

Alpha-, beta- and kappa-caseins inhibit the proliferation of the myeloid cell lines 32D cl3 and WEHI-3 and exhibit different differentiation properties.

We have recently shown that sodium caseinate (CasNa) was able to inhibit the proliferation of the myeloid cell line 32D cl3 in a non-toxic way, and that it also induced the expression of macrophage colony-stimulating factor (M-CSF). Casein is the main protein present in milk and is composed of alpha (alpha), beta (beta) and kappa (kappa) subunits. This work was undertaken to evaluate if any one casein is responsible for the proliferation and differentiation properties found for CasNa on myeloid cells. Taking into consideration that 32D cl3 cells are considered to be non-malignant and dependent on IL-3 for proliferation, we also included for this study a leukemic cell line, WEHI-3, that does not depend on any external growth factor for its proliferation in order to evaluate if the growth inhibitory effect of caseins is also present for malignant cells. Our results showed that all caseins were inhibitory for the proliferation of either 32D cl3 and WEHI-3 and that only the 32D cl3 cells were induced to differentiate into the monocyte-macrophage lineage. In order to evaluate if CasNa was able to inhibit the proliferation of other myeloid cells we used J774 and P388 and found that they were also inhibited. We also determined that the different caseins exhibit different differentiation properties, with alpha-casein being the only one able to induce the secretion of M-CSF. We consider this work to open a new field of research, where casein, or its components, can be studied for their possible role in hematopoiesis and on the inhibition of malignant cell proliferation for therapeutic use.

Influence of ethanol withdrawal on fear memory: Effect of D-cycloserine.

Animals made dependent via an ethanol (ETOH) -containing liquid diet (6% v/v) for 14 days were subjected to a contextual fear conditioning paradigm 3 days after the last consumption day. After conditioning, rats were subjected to four extinction trials by exposing the animals to the conditioned context and their freezing was evaluated for each trial. Immediately after the first extinction trial, animals were injected with D-cycloserine (DCS) 5 mg/kg i.p., a dose that did not influence the extinction in control rats. Spontaneous recovery of learned fear was tested seven days after the last extinction trial. The following day, animals were subjected to a reacquisition or a reinstatement procedure and their freezing responses evaluated 24 h later. The present study shows that: 1. discontinuation from chronic ETOH administration facilitated the formation of a new fear memory concomitant with a marked resistance to being extinguished, 2. administration of DCS (5 mg/kg) facilitated the extinction process only in ETOH withdrawn rats, 3. both reinstatement and reacquisition procedures restored the increased freezing in ETOH withdrawn animals after extinction, 4. DCS administered immediately after the first extinction trial prevented the increase in freezing following both reacquisition and reinstatement. The enhanced sensitivity to the facilitatory effect of DCS in ETOH withdrawn animals may be mediated by adaptive changes in N-methyl-D-aspartate (NMDA) receptor provoked by ETOH dependence.

Midazolam disrupts fear memory reconsolidation.

The current research examines the influence of midazolam (MDZ) on memory reconsolidation using a contextual fear paradigm in rats, based on three context-shock training trials (0.7 mA, 3 s). First, we evaluate the effect of MDZ (1 mg/kg, i.p.) injected shortly after the training procedure. Second, we examined the influence of MDZ after a brief exposure (90 s) either in the training context (reactivation procedure) or in a neutral environment (no reactivation procedure) and one day later, freezing behavior was scored when rats were re-exposed to the training environment. Third, we investigate both the effect of MDZ administered at different times following reactivation on fear memory and the persistence of such effect 10 days after reactivation. Finally, we test whether the MDZ effect could be reverted by a single weak training trial (0.2 mA, 3 s) or by the presentation of the same unconditioned stimulus in the absence of the conditioned stimulus as a reminder which proves to induce significant freezing in rats not previously trained. Results show that MDZ interferes with the formation of a contextual fear memory only when administered after the reactivation procedure but not after the training procedure. This interference was effective up to 60 min after reactivation and not at a later time. No spontaneous recovery of freezing behavior was observed 11 days after MDZ injection which was not reverted by a weak training trial and by the unconditioned stimulus alone. All these data support the idea that stimulating GABA A receptor sites via MDZ selectively disrupts the reconsolidation process of a contextual fear memory.

[Modification of clinical profile of stroke in atrial fibrillation patients. Effect of antithrombotic treatment]. / Modificacion del perfil clinico de los ictus en enfermos con fibrilacion auricular. Efecto del tratamiento antitrombotico.

BACKGROUND: Atrial fibrillation is present in 24% of the population over 60 and it increases the risk of stroke by 2,4% 3%/year. Antithrombotic treatment is considered as the treatment of choice for cardioembolic stroke prevention in this patients. As far as we know there are not relevant data about the influence of these treatments on the type of stroke that may develop in these patients. AIM: Analyze whether there are differences in the clinical profile and functional prognosis after stroke in patients with atrial fibrillation depending on the type of treatment they were on at the time of occurrence of the event. PATIENTS AND METHODS: We identified 67 patients who were admitted consecutively to our stroke unit with a stroke and atrial fibrillation over a period of 2 years. Patients were classified according to the type of antithrombotic treatment they were on. Functional prognosis was estimated by Rankin score at discharge. RESULTS: Treated patient showed a non significant tendency to suffer less severe strokes and present a better functional situation at discharge than those who were not on prophylactic treatment. Treated patients had a significant higher prevalence of previous TIA (44,2% vs 9,1%; p= 0,0042) and HBP (81,4% vs 52%; p= 0,041) than non treated patients. Embolic strokes were more frequent in non treated patients. CONCLUSION: Antithrombotic treatment not only prevents strokes but may also contribute to the development of less severe strokes with a better functional prognosis in patients with AF and does not contribute to increase complications in these group of patients.

Experiencia y resultados del tratamiento de pacientes con cáncer de vesícula biliar / Experience and results of patients treatment with gallblader cancer

Antecedentes: El cáncer de la vesícula biliar (CaVB) persiste como una neoplasia frecuente, y en general del mal pronóstico. Los tratamientos utilizados hasta la fecha son diversos, pero en general coinciden en la práctica de una resección quirúrgica de aseo, asociado o no a esquemas de neoadyuvancia y adyuvancia, ya sean éstos de quimio y/o radioterapia. Objetivo: Describir los resultados de un protocolo de tratamiento para CaVB en diferentes estadios de la enfermedad. Material y Método: Estudio observacional, descriptivo y prospectivos para valorar un esquema terapeútico en pacientes con CaVB, realizado entre julio de 1994 y julio de 2000. Se trataron consecutivamente a todos los pacientes colecistectomizados cuyo estudio histológico reveló carcinoma infiltrante de la vesícula biliar y se encontraban en etapas intermedias y avanzadas de la enfermedad. Para ello, se realizó bisegmentectomía parcial de los segmentos IV y V del hígado y linfadenectomía regional, asociada a una adyuvancia con quimioterapia ambulatoria en base a 5-FU y leucovorina (6 ciclos). Con un seguimiento promedio de la serie de 35,6 meses, se valoró evolución, morbilidad, mortalidad operatoria, y supervivencia actuaria. Se realizó un análisis exploratorio descriptivo de los datos y análisis de supervivencia. Resultados: Fueron incluidos en este protocolo 20 pacientes, con una edad promedio de 60,9 años (42-85 años), de los cuales 15 son mujeres (75 por ciento). Nivel de invasión: muscular 5 pacientes (25 por ciento), subserosa 6 casos (30 por ciento), serosa 6 pacientes (30 por ciento), y grasa perivesicular 3 casos (15 por ciento). La morbilidad de la serie fue de 30 por ciento. No hubo mortalidad operatoria. La quimioterapia fue bien tolerada, y sólo un paciente no la completó pues falleció antes. La supervivencia actuarial global de la serie fue de 76,5 por ciento a los 60 meses. Conclusiones: El tratamiento realizado es satisfactorio desde el punto de vista de la morbilidad y mortalidad, con una supervivencia actuarial global y por estadio, dentro de rangos aceptables

Chronic benzodiazepine administration facilitates the subsequent development of ethanol dependence.

This study investigated the effect of chronic benzodiazepine (BZD) administration and its abrupt discontinuation on later subsequent ethanol consumption employing a free choice paradigm between water and increasing ethanol concentrations. In addition, we also studied the anxiolytic and reinforcing properties of ethanol assessed in the elevated plus maze (EPM) and in the conditioned place preference paradigm, respectively. Adult male Wistar rats were subjected to a chronic diazepam (DZM) treatment (2 mg/kg/day, i.p.) during 21 days. Twenty-four hours after that treatment and, in another experiment, 10 days after the last DZM injection, rats were subjected to an oral ethanol self-administration procedure (ethanol was increased in concentration (v/v) on 4 consecutive days as follows: 2%, 4%, 6%, 8% followed by an additional period of 8 days in which animals were offered a 10% (v/v) ethanol solution. Diazepam treated rats showed a higher ethanol intake and spontaneous signs of ethanol withdrawal when the access to ethanol was discontinued. These results were observed when ethanol was available at day 1 of withdrawal but not when DZM treated rats were initiated in the ethanol choice test 10 days after BDZ withdrawal. Furthermore, DZM treated rats exhibited an increased anxiolytic ethanol induced effect (1 g/kg, i.p.) in the EPM and a significant ethanol-induced conditioned place preference (1 g/kg, i.p.). These data suggest that early DZM treatment facilitates ethanol consumption and the development of ethanol dependence.

Strand displacement amplification and homogeneous real-time detection incorporated in a second-generation DNA probe system, BDProbeTecET.

BACKGROUND: Amplified DNA probes provide powerful tools for the detection of infectious diseases, cancer, and genetic diseases. Commercially available amplification systems suffer from low throughput and require decontamination schemes, significant hands-on time, and specially trained laboratory staff. Our objective was to develop a DNA probe system to overcome these limitations. METHODS: We developed a DNA probe system, the BDProbeTecTMET, based on simultaneous strand displacement amplification and real-time fluorescence detection. The system uses sealed microwells to minimize the release of amplicons to the environment. To avoid the need for specially trained labor, the system uses a simple workflow with predispensed reagent devices; a programmable, expandable-spacing pipettor; and the 96-microwell format. Amplification and detection time was 1 h, with potential throughput up to 564 patient results per shift. We tested 122 total patient specimens obtained from a family practice clinic with the BD ProbeTecET and the Abbott LCx(R) amplified system for the detection of Chlamydia trachomatis and Neisseria gonorrhoeae. RESULTS: Based on reportable results, the BDProbeTecET results for both organisms were 100% sensitive and 100% specific relative to the LCx. CONCLUSIONS: The BDProbeTecET is an easy-to-use, high-throughput, closed amplification system for the detection of nucleic acid from C. trachomatis and N. gonorrhoeae and other organisms.

Respuesta inmunológica de linfocitos T frente a diferentes fracciones antigénicas de mycobacterium bovis en poliartritis crónica juvenil / T lymphocyte immunological response to different antigenic fractions of mycobacterium bovis in juvenile chronic polyarthritis

Background: The possible relationship of stress or heat-shock proteins (hsp) with the pathogenesis of autoimmune disease has been intensely studied recently. In adult rheumatoid arthritis, a bacterial hsp (65 kDa hsp from Mycobacterium tuberculosis or bovis) would have a cross reactivity with a hsp of ARTICULAR cartilage. Aim: To assess the cellular immune response to the 65 kA hsp from M Bovis in children. Patients and methods: The proliferative response of peripheral mononuclear cells of 20 children with juvenile chronic polyarthritis and 20 healthy controls, against the 65 kDa hsp and other antigenic fractions from M bovis, was studied. Results: Patients with juvenile chronic polyarthritis had a intense reaction against 65 kDa fraction and a second fraction located between 32.5 and 27.5 kDa. Patients with a prolonged evolution of the disease (more than five years), reacted preferentially to an antigenic segment located between 32.5 and 27.5 kDa and those with a shorter evolution did so with an antigen of 27.5-18.5 kDa. Conclusions: These results support the hypothesis that 65 kDa hsp from M bovis is involved in the pathogenesis of chronic juvenile polyarthritis and suggest that patients with short or prolonged evolutions of the disease would react to different antigenic fractions

Benzodiazepine withdrawal facilitates the subsequent onset of escape failures and anhedonia: influence of different antidepressant drugs.

The effect of benzodiazepine (BDZ) withdrawal on escape acquisition and on the behavioral response to two different reinforcing stimuli was investigated. In addition, the influence of antidepressant drugs (AD) differing in their mechanism of action on these behavioral outputs was also evaluated. Rats subjected to withdrawal from a chronic treatment with diazepam (DZM; 2 mg/kg per day, i.p.) during 21 days were subsequently exposed to a brief inescapable shock session (IS) and 48 h later to an active avoidance test. Only withdrawn animals exposed to the IS exhibited enhanced escape failures. In an additional experiment, withdrawn rats were repeatedly administered with vehicle (VEH), desipramine (DMI; 5 mg/kg, i.p.), fluoxetine (FLU; 5 mg/kg, i.p.) or phenelzine (PHEN; 5 mg/kg, i.p.) and subsequently exposed to IS and to active avoidance task. A significant reversal of escape deficit was only observed following DMI and PHEN but not after FLU. Furthermore, withdrawn rats showed a reduced preference for a sexually relevant olfactory cue, this reduced sensitivity was only normalized following DMI but not after the administration of FLU or PHEN. Finally, rats exposed to abrupt cessation of chronic BDZ administration did not exhibit preference for a context previously associated with amphetamine (AMP) under the conditioned place preference (CPP) procedure. All these findings are indicative that BDZ withdrawal facilitates the subsequent occurrence of behavioral changes-escape failures and reduced behavioral response to rewarding stimuli-suggested to parallel important symptoms of human depression. In addition, DMI seems to be much more effective in restoring such behavioral abnormalities as compared to a MAO inhibitor and to a inhibitor of 5-HT uptake.

[Development and evaluation of a measure scale of risk of mother-newborn infant relations]. / Construcción y evaluación de pauta de medición de riesgo relacional madre-recién nacido.

The purpose of this work was to construct and assess a scale aimed to detect risky relationships between mothers and newborns that could predict future child abuse and neglect. The instrument was applied in two opportunities, by a trained midwife and by an expert in mental health, to a sample of 106 mother-newborn dyads. When both assessments were compared, the concordance to assess relationship risk was 99.3%. The reliability of the scale, measured with the Crombach, an internal consistence index, was 0.88. Those items with a low discriminative capacity were eliminated. The massive use of the resultant scale, that is easy to apply and highly reliable, could help to prevent child abuse and neglect.

Reaching out. Locating and lengthening the interdomain linker in AraC protein.

A genetic method was developed to determine, in proteins, areas which are tolerant of insertions and deletions. Attractive candidates for these areas are linker regions. Such a region was found to include positions 171 to 178 in the Escherichia coli regulatory protein AraC. Independent biochemical methods identified amino acid residues 11 to 170 as the minimal dimerization domain of AraC, and amino acid residues 178 to 286 out of the 291 residue protein as the minimal DNA-binding domain. Hence, by both the genetic and biochemical approaches, the interdomain linking region was determined to include amino acid residues 171 to 177. The properties of altered proteins were examined using templates with AraC half-sites more widely separated than in the wild-type case. Both AraC protein containing an insertion in the interdomain linker region and a protein consisting of the minimal functional dimerization and DNA-binding domains separated by a 39 amino acid residue linker were able to bind to and function on such a DNA site. In vitro, the proteins with longer linkers bound substantially more stably than wild-type AraC to the DNA containing half-sites for AraC separated by an extra two helical turns of DNA. In vivo on an ara promoter with the more widely separated AraC half-sites, the proteins could activate transcription much better than wild-type AraC.

Functional domains of the AraC protein.

The AraC protein, which regulates the L-arabinose operons in Escherichia coli, was dissected into two domains that function in chimeric proteins. One provides a dimerization capability and binds the ligand arabinose, and the other provides a site-specific DNA-binding capability and activates transcription. In vivo and in vitro experiments showed that a fusion protein consisting of the N-terminal half of the AraC protein and the DNA-binding domain of the LexA repressor dimerizes, binds well to a LexA operator, and represses expression of a LexA operator-beta-galactosidase fusion gene in an arabinose-responsive manner. In vivo and in vitro experiments also showed that a fusion protein consisting of the C-terminal half of the AraC protein and the leucine zipper dimerization domain from the C/EBP transcriptional activator binds to araI and activates transcription from a PBAD promoter-beta-galactosidase fusion gene. Dimerization was necessary for occupancy and activation of the wild-type AraC binding site.

Light-regulated expression of the psbD gene family in Synechococcus sp. strain PCC 7942: evidence for the role of duplicated psbD genes in cyanobacteria.

The genome of the cyanobacterium Synechococcus sp. strain PCC 7942 contains two psbD genes encoding the D2 protein of the photosystem II reaction center: psbDI, which is cotranscribed as a discistronic message with psbC (the gene encoding CP43, a chlorophyll-a binding protein), and psbDII, which is monocistronic. Northern blot analysis of psbD transcripts showed that the two genes responded differently when wild-type cells were shifted from moderate to high light intensity. Whereas psbDII transcripts increased 500% relative to unshifted control cells, psbDI-psbC transcripts remained unchanged. The beta-galactosidase activities expressed from translational fusions between the psbD genes and the Escherichia coli lacZ reporter gene displayed responses similar to those seen in the RNA. D2 protein levels in thylakoid membranes from wild-type cells increased to 250% of those of the unshifted control cells 12 h after a shift to high light intensities. In contrast, in a mutant strain (AMC016) that carries an inactive psbDII gene, D2 levels decreased by 50% under identical conditions. These results suggested that induction of psbDII gene expression by light can serve as a supplementary system for maintaining a functional photosystem II reaction center at high light intensity. This hypothesis was corroborated by mixed-culture experiments, in which AMC016 cells competed poorly with wild-type cells at high light intensity. These data suggest for the first time that differential expression of members of a cyanobacterial gene family serves to maintain a functional PSII reaction center under diverse environmental conditions.