Biomedical subjects

J Vallejo

Publications and source records attributed to J Vallejo.

At least 19 recordsLinked to original sources

PubMed2005

Randomized clinical trial of the effect of intravenous fluid administration on hormonal and renal dysfunction in patients with obstructive jaundice undergoing endoscopic drainage.

BACKGROUND: Renal dysfunction in patients with biliary obstruction is associated with extracellular water depletion. This study examined the effect of preoperative saline infusion before biliary drainage on hormonal and renal functional derangements in patients with obstructive jaundice. METHODS: In a randomized study, 49 patients with malignant obstructive jaundice were investigated at baseline, on the day of drainage, and at 24 h, 72 h and 7 days after internal endoscopic biliary drainage. Patients were randomized to receive (n = 22) or not to receive (n = 27) 3000 ml normal saline intravenously for 24 h before drainage. Variables analysed included extracellular water volume, creatinine clearance, and serum levels of aldosterone, renin, atrial natriuretic peptide (ANP), vasopressin and albumin. RESULTS: Preoperative saline infusion produced a rise in creatinine clearance, diuresis, ANP concentration and extracellular water volume but this did not translate into better recovery of renal function after operation. Drainage produced a fall in creatinine clearance in all patients, but hormonal and renal function had recovered by 2 days after restoration of bile flow, independently of preoperative hydration. CONCLUSION: Fluid administration expands the extracellular water compartment before drainage but fails to improve renal function after drainage. Definitive improvement in endocrine and renal function requires the restoration of bile flow into the duodenum.

Adult↗

PubMed2005

Onset of antidepressant action: a pharmacological question?

OBJECTIVE: This study was conducted to analyse the onset of action of antidepressants in naturalistic conditions. METHOD: Multicenter, prospective, open-label, non-comparative naturalistic study among 582 depressed outpatients treated with mirtazapine. The patients were assessed at screening, and after 1, 2 and 4 weeks by the 17-item Hamilton depression rating scale (17-HAM-D) and clinical global impression (CGI). Onset of action was measured by traditional analyses based on the time to a persistent reduction of more than 50% from baseline on the 17-HAM-D. Patients were grouped into four groups: very fast responders, fast responders, traditional responders and partial or non-responders. The non-parametric Kruskall-Wallis test was used to assess differences between the groups and logistic regression to predict response after 1 week of treatment. RESULTS: 16% of patients had a very fast response, 42.1% a fast response, 26.5% a traditional response and 15.5% a partial or non-response. There were no significant differences between these groups with regard to dose of mirtazapine or sociodemographic characteristics. The baseline total 17-HAM-D was lower in the faster groups than in the slower groups. The evolution of 17-HAM-D items was similar in each responder group. CONCLUSION: Time to response varied from early faster response to late slower response. The evolution of 17-HAM-D for each type of response was similar, but occurred at a different time in each group.

Adolescent↗

PubMed2005

Contribution of NTRK2 to the genetic susceptibility to anorexia nervosa, harm avoidance and minimum body mass index.

Anorexia nervosa (AN) and bulimia nervosa (BN) are eating disorders (ED) with complex genetic and environmental components. Genetic studies and animal models support the participation of brain-derived neurotrophic factor (BDNF) in the vulnerability to AN and BN. We investigated the genetic contribution of the BDNF-specific receptor neurotrophic tyrosine kinase receptor type 2 (NTRK2) to the susceptibility to ED. We have screened the entire NTRK2 gene in 91 patients with ED and have identified 14 single-nucleotide polymorphisms (SNPs). A population-based association study with six SNPs from the NTRK2 locus was performed in 164 ED patients and 121 controls. Significant evidence of association for markers -69C>G and IVS13+40G>A was detected. We also observed a strong association between the C-A-insC haplotype (-69/IVS13+40/2784-2785) and binge-eating/purging AN (ANP, P=0.006; OR=2.27), and a reduced frequency of haplotype G-A-delCl in BN patients (P=0.034; OR=0.6). The analysis of ED-related phenotypes revealed a clear association between NTRK2, high scores of Harm avoidance measured by the temperament and character inventory (TCI-R; P=0.003) and minimum body mass index (minBMI; P<0.001). Our data support a contribution of NTRK2 to the genetic susceptibility of ED, mainly ANP, and ED-related phenotypic traits, such as Harm avoidance and minBMI.

Adult↗

PubMed2003

Auditory event-related potentials in 50 melancholic patients: increased N100, N200 and P300 latencies and diminished P300 amplitude.

BACKGROUND: To investigate whether there are some differences in Event-Related Potentials (ERP) between melancholic patients and healthy controls. To establish whether there is a relationship between abnormalities of ERP and severity of depression and psychomotor retardation. METHOD: Melancholic depressed patients (N=50) and normal comparison subjects (N=31) were assessed for latencies and interlatencies of N100, N200, N400, latency and amplitude of P300. The ERPs were studied with an 'oddball paradigm' in the auditory modality. Severity of depression was measured by the Hamilton Depression Rating Scale (HDRS) and psychomotor retardation with the Depressive Retardation Rating Scale (DRRS). RESULTS: The melancholic group showed a significantly higher latency in N100 (P<0.001), N200 (P<0.001) and P300 (P<0.001) and a significantly lower P300 amplitude (P<0.001) than healthy controls. No other differences were found either in the latencies of the N400 or in their interlatencies. HDRS and DRRS do not have any significant correlations with amplitude or latency measures. LIMITATIONS: The subjects of this study are inpatients, with a severe subcategory of depression and high average age. It is difficult to generalize these findings. CONCLUSIONS: The principal finding of this study is the increase in three of the four latencies measured (N100, N200 and P300) and in the decreased P300 amplitude in melancholic patients compared to normal controls. There is no association between these abnormalities and clinical variables.

Depressive Disorder↗

PubMed2003

[Neuroactivation of the Tower of Hanoi in patients with obsessive-compulsive disorder and healthy volunteers].

UNLABELLED: The aim of the study was to evaluate changes in regional cerebral blood flow (rCBF) in obsessive-compulsive disorder (OCD) patients and healthy controls during performance of Tower of Hanoi (TOH) test (cognitive task). MATERIAL AND METHODS: We compared TOH test performance in 30 OCD patients and 30 individually matched healthy volunteers. Intelligence and anxiety measurements were taken into account for all participants. Within the patient group, factors such as duration and severity of symptoms and low mood were considered. rCBF was estimated through the uptake of 99mTc-hexamethylpropylamine-oxime (HMPAO) on single photon emission computerised tomography (SPECT). Regional values were quantified as ratios of cortical blood flow. RESULTS: OCD patients and volunteers differed significantly in terms of subjective anxiety during procedures. TOH test performance was significantly impaired in OCD patients when compared with matched controls. 2-tailed t tests for repeated measures suggested that there were overall significant differences (p = 0.039) between both groups (OCD patients and controls) confined to left caudate activation. There was increased activity after activation in control subjects, but not in OCD patients. No differences in other regions were observed. CONCLUSIONS: These results suggest a modification of the activating systems of basal ganglia functions in OCD compared with normal subjects.

Adolescent↗

PubMed2003

Met66 in the brain-derived neurotrophic factor (BDNF) precursor is associated with anorexia nervosa restrictive type.

Several lines of evidence support a role for brain-derived neurotrophic factor (BDNF) alterations in the etiology of eating disorders (EDs). BDNF heterozygous knockout mice show alterations in eating behavior, increased body weight and adipocyte hypertrophy. BDNF also regulates the synaptic efficiency through the modulation of key neurotransmitter systems previously known to be involved in ED. These findings, together with the fact that this neurotrophin is expressed in the hypothalamus nuclei associated with weight regulation and feeding control, led us to propose BDNF as a candidate gene for ED. To investigate the possible involvement of this neurotrophin in eating behavior, we screened the BDNF gene in 95 ED patients and identified four sequence variants. Two of them, -374A/T and -256G/A, were found in two patients with anorexia nervosa (AN) and consisted of single-nucleotide mutations within the 5' untranslated region (5'UTR). The other two polymorphisms resulted in a C to T transition located at the 5'UTR of the BDNF gene and an amino-acid substitution within the BDNF precursor protein (Val66Met). We performed a case-control study for these two Single-nucleotide polymorphisms in a sample of 143 ED patients and 112 unrelated controls and found a strong association of restricting AN (ANR) with the Met allele of the Val66Met BDNF polymorphism (2p=0.002). There was also evidence for a significant effect of this sequence variant on the minimum body mass index (MBMI) (2p=0.006). These results suggest that the BDNF Met66 variant may be a susceptibility factor to ED, mainly to ANR and low MBMI.

Adult↗

PubMed2002

Loss of the circadian variation of platelet [3H]imipramine binding in delusional compared with non-delusional endogenously depressed patients.

BACKGROUND: The circadian variations of the serotonin reuptake sites were studied in 16 patients meeting DSM-IV criteria for major depression with melancholia, either with (n=8) or without (n=8) psychotic symptomatology. METHOD: The [3H]imipramine binding sites were measured in platelet samples. RESULTS: While no statistically significant difference was found between the morning (09:00 h) and evening (21:00 h) [3H]imipramine B(max) values in the control group, both the non-delusional and delusional melancholic patients showed higher evening than morning B(max) values, which were only statistically significant in the former. When both diagnostic groups were compared, the delusional patients showed significantly lower [3H]imipramine binding values than the non-delusional patients both in the morning and evening samples. Within the non-delusional depressed patients, those individuals with mood circadian variation, assessed by the 18th item of the HDRS, showed significantly lower B(max) values than those without mood variation. Lowest morning and evening B(max) values were noted in the delusional depressed group without mood variations. CONCLUSIONS: These results suggest that delusional depressions might have a different neurobiological substrate with loss of chronobiological rhythms.

Antidepressive Agents, Tricyclic↗

PubMed2002

Obsessive-compulsive disorder (OCD) patients are impaired in remembering temporal order and in judging their own performance.

Obsessive-compulsive disorder (OCD) has been related to frontostriatal dysfunction, but some inconsistencies between studies and a relative paucity of neuropsychological research still characterizes the study of OCD. We compared 28 patients with OCD and matched healthy controls on two neuropsychological tests sensitive to frontal dysfunction: temporal ordering and a "feeling-of-doing" (FOD) judgment about ordering. The OCD group performed significantly worse than controls in the temporal ordering task despite showing normal recognition memory. Patients were also impaired in "feeling-of-doing" judgments suggesting they have a lack of self-awareness of their performance. Thus, the results of the current study reinforces previous research that indicates that OCD patients fail on tasks that require adequate functioning of the frontal-striatal pathways.

Adolescent↗

PubMed2001

Impairment of incidental memory for frequency in patients with obsessive-compulsive disorder.

The aim of our study was to investigate whether patients with obsessive-compulsive disorder (OCD) have impaired incidental memory for frequency. Fifty-four subjects (27 OCD patients and 27 matched control subjects) performed a task assessing estimation of occurrence of previously heard words. Performance on this task was compared with other intentional verbal memory tasks (recognition, recall and learning of common words). We also correlated memory for frequency with frontal lobe tests (Wisconsin Card Sorting Test, Trail Making Tests A and B, and verbal fluency). Performance on incidental learning of frequency was significantly worse in the OCD group than in control subjects. Other verbal memory measures did not show significant differences. Performance in the frequency task correlated with verbal fluency. Although intentional verbal memories are normal in OCD patients, incidental memory for frequency is impaired, suggesting that prefrontal systems are involved in OCD.

Adolescent↗

PubMed2001

Right prefrontal repetitive transcranial magnetic stimulation in obsessive-compulsive disorder: a double-blind, placebo-controlled study.

OBJECTIVE: The efficacy of repetitive transcranial magnetic stimulation (rTMS) of the right prefrontal cortex for patients with obsessive-compulsive disorder (OCD) was studied under double-blind, placebo-controlled conditions. METHOD: Patients were randomly assigned to 18 sessions of real (N=10) or sham (N=8) rTMS. Treatments lasted 20 minutes, and the frequency was 1 Hz for both conditions, but the intensity was 110% of motor threshold for real rTMS and 20% for the sham condition. RESULTS: No significant changes in OCD were detected in either group after treatment. Two patients who received real rTMS, with checking compulsions, and one receiving sham treatment, with sexual/religious obsessions, were considered responders. CONCLUSIONS: Low-frequency rTMS of the right prefrontal cortex failed to produce significant improvement of OCD and was not significantly different from sham treatment. Further studies are indicated to assess the efficacy of rTMS in OCD and to clarify the optimal stimulation characteristics.

Adult↗

PubMed2001

Long-term follow-up and predictors of clinical outcome in obsessive-compulsive patients treated with serotonin reuptake inhibitors and behavioral therapy.

BACKGROUND: The objective of this study was to examine the long-term course of obsessive-compulsive disorder (OCD) in patients treated with serotonin reuptake inhibitors (SRIs) and behavioral therapy and to identify predictors of clinical outcome. METHOD: Sixty outpatients meeting DSM-II-R or DSM-IV criteria for OCD were followed up for 1 to 5 years (mean = 2.5 years). All of them received prolonged pharmacologic therapy with an SRI. RESULTS: Thirty-seven patients (61.7%) completed an adequate behavioral treatment. At long-term assessment, 22 patients (36.7%) exhibited a global Yale-Brown Obsessive Compulsive Scale (Y-BOCS) score greater than 16 or a final reduction in Y-BOCS global score of less than 35% and were considered nonresponders. Patients who completed behavioral therapy showed a significant decrease in Y-BOCS compulsions subscale score (p = .01), whereas no significant differences in either Y-BOCS global or obsessions subscale scores between those who did and those who did not undergo behavioral therapy were detected. Obsessions of sexual/religious content were the unique factor related to a poorer long-term outcome. CONCLUSION: A substantial number of OCD patients showed persistent disabling symptoms at the long-term follow-up in spite of combined pharmacologic and behavioral treatment. Major benefits from behavioral therapy appeared to be the improvement of ritualistic behaviors. Sexual/religious obsessions predicted poorer long-term outcome, whereas short-term response to SRI treatment failed to achieve predictive value in the long-term course of OCD.

Adolescent↗

PubMed2000

Altered 5-HT(2A) binding sites and second messenger inositol trisphosphate (IP(3)) levels in hippocampus but not in frontal cortex from depressed suicide victims.

The binding parameters of 5-HT(2A) and levels of its second messenger, 1,4,5-trisphosphate (IP(3)), were simultaneously studied in frontal cortex and hippocampus from the brains of 18 control subjects and 18 depressed suicide victims. All suicides met DSM-III-R criteria for depressive symptoms, suffered a violent death and had not taken any antidepressant drugs for at least 6 months prior to death. A significant decrease in the number of 5-HT(2A) binding sites (154+/-22 vs. 254+/-36 fmol/mg), together with a significantly lower apparent affinity constant (1.02+/- 0.08 vs. 1. 36+/-0.09 nM), was detected in hippocampus but not in frontal cortex from the depressed suicides compared to the control subjects. Furthermore, IP(3) concentrations were significantly increased in hippocampus (3.2+/-0.3 vs. 2.1+/-0.3 pmol/g) but not in frontal cortex (1.3+/-0.3 vs. 2.7+/-0.5 pmol/g) from the suicide victims. The reported results may indicate a significant hypersensitivity of the 5-HT(2A) postsynaptic receptor located in the hippocampus from depressed suicide victims, giving rise to an enhancement of its intracellular signaling system with higher IP(3) production.

Adolescent↗

PubMed1999

Functional magnetic resonance imaging study of frontal lobe activation during word generation in obsessive-compulsive disorder.

BACKGROUND: Functional imaging studies have demonstrated abnormal patterns of brain activity in obsessive-compulsive disorder, which consistently suggest the alteration of frontal lobe functioning. We performed a brain activation study in obsessive-compulsive disorder using a cognitive task involving the frontal lobes. METHODS: Twenty patients and 20 healthy control subjects were assessed with functional magnetic resonance imaging during a phonologically guided word generation task. The study analysis was based on the comparison of group average time-course functional changes occurring at the site of largest frontal cortex activation during alternating rest and task periods. RESULTS: In terms of relative signal changes, patients showed a significantly greater activation during word generation and a defective suppression of this activation during the following rest period. Both abnormal imaging findings significantly correlated with the severity of the clinical process assessed by the Yale-Brown Obsessive-Compulsive Scale. CONCLUSIONS: The results indicate that functional magnetic resonance imaging during cognitive challenge may be useful to reveal distinctive features of latent brain dysfunction in obsessive-compulsive disorder.

Adolescent↗

PubMed1999

Neuropsychological functioning in a subclinical obsessive-compulsive sample.

BACKGROUND: Previous neuropsychological research has suggested that the study of psychometrically defined subclinical samples might be a valid approach to understand the underlying pathophysiology of obsessive-compulsive disorder (OCD). This approach has the potential benefit of overcoming some of the methodological problems linked to the use of clinical samples. METHODS: A group of subclinical obsessive-compulsive (OC) subjects (n = 35), selected on the basis of their scores on the Padua Inventory, and a control group were assessed on executive functioning tasks and other neuropsychological tests which have been demonstrated to be impaired in clinical OCD patients and/or in those with several basal ganglia disorders. RESULTS: Subclinical OC subjects needed significantly more moves than controls to reach the solution criteria on the Tower of Hanoi puzzle, and performance on this test was positively correlated with total score and the Checking factor of the Padua Inventory. There were no between-group differences on the other frontal lobe tests. CONCLUSIONS: The results suggest that deficits in manipulating spatial information might be basic in OCD, and are congruent with the involvement of the frontostriatal circuits in the disorder.

Adult↗

PubMed1999

Reduced design fluency in subclinical obsessive-compulsive subjects.

This study examined the verbal and design fluency abilities of 25 subclinical obsessive-compulsive (OC) subjects and 27 noncompulsive control subjects. As hypothesized, the OC group showed reduced design fluency, and design fluency was also negatively correlated with obsessionality. These results provide further evidence for the involvement of the right corticostriatal systems in the mediation of OC behaviors, extending the findings to individuals with subclinical symptoms.

Adult↗

PubMed1999

[CEA, CA 19.9 and CA 195 in patients with colorectal carcinoma. ROC analysis].

The aim of this study was to assess the utility of determining serum levels of the CEA, CA 19.9 and CA 195 tumor markers in 906 patients with colorectal carcinoma for a 5-year follow-up period. In addition to calculating sensitivity and specificity for the common normal limits, the results were analyzed with RO curves. Sensitivity values for 90% and 95% specificity were also obtained. The results of the areas under the curve (CEA: 0.887; CA 19.9: 0.802; CA 195: 0.971) and sensitivities and specificities at different normality limits showed better behavior for CEA with respect to CA 19.9 and CA 195, the last two presenting similar results. CEA continues to be the best tumor marker to monitor patients with colorectal carcinoma.

Adenocarcinoma↗

PubMed1998

Variations in [3H]imipramine and 5-HT2A but not [3H]paroxetine binding sites in suicide brains.

Both the [3H]imipramine and [3H]paroxetine binding sites and the 5-HT2A receptor were simultaneously determined in frontal cortex, cingulate cortex, hippocampus and amygdala from 17 control subjects and 17 depressed suicide victims. A significant decrease in the maximum binding (Bmax) of [3H]imipramine was observed in the hippocampus of suicide victims as compared to control subjects (160 +/- 25 vs. 328 +/- 52 fmol/mg protein; P = 0.007) without changes in the apparent affinity constant (Kd). Furthermore, a significant decrease in the number of 5-HT2A binding sites, together with a significantly lower Kd, was also observed in the hippocampus of suicides as compared to control subjects (129 +/- 18 vs. 225 +/- 32 fmol/mg protein; P = 0.02 and 0.91 +/- 0.07 vs. 1.38 +/- 0.08 nM, respectively; P = 0.006). [3H]Paroxetine binding did not display modifications between the two groups in either Bmax or Kd from any of the brain regions studied. When all four brain regions were taken together, a down-regulation was noted between presynaptic [3H]imipramine binding and the postsynaptic 5-HT2A receptor (r = -0.40; P = 0.0013) in the control group. This correlation did not appear in the suicide group. No correlation was observed between [3H]paroxetine binding and the 5-HT2A receptor in either control subjects or suicides. Taken together, these results suggest that the 5-HT uptake site measured with [3H]imipramine and the 5-HT2A receptors are reliable markers of serotonergic dysfunction.

Adult↗

PubMed1998

Outpatient group therapy for anorexia nervosa: a preliminary study.

Group therapy is generally recognized as an important form of psychotherapy for anorexia nervosa patients, but there are few controlled studies of its effectiveness. The aim of the current study was to determine the effectiveness of cognitive-behavioural therapy (CBT) for the treatment of anorexia nervosa in outpatients. Twenty-six outpatients with anorexia nervosa, were assessed for depression (BDI, Beck Depression Inventory), eating psychopathology (EDI, Eating Disorders Inventory), eating attitudes (EAT, Eating Attitudes Test) and weight at the beginning and at the end of the treatment and at one year follow-up. Our results substantiate the effectiveness of the CBT approach as a treatment and also at one year follow-up. Good EAT scores were observed in 70% of our cases after the treatment and in 60% at follow-up. Further research should assess the effectiveness of therapeutic groups more intensively because of their economic advantages.

Adolescent↗