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R Vidal

Publications and source records attributed to R Vidal.

At least 19 recordsLinked to original sources
PubMed2007

Clinicopathologic features of frontotemporal dementia with progranulin sequence variation.

BACKGROUND: Frontotemporal lobar degeneration with ubiquitin-immunoreactive (ub-ir) inclusions (FTLD-U) has been associated with frontotemporal dementia (FTD) and ALS. Recently, mutations in Progranulin (PGRN), predicted to cause premature truncation of the PGRN coding sequence, were found in patients with inherited FTLD-U and ub-ir neuronal intranuclear inclusions (NII). OBJECTIVE: To describe clinical, pathologic, and genetic features of three FTD patients having either a family history of FTD (A.III.1 and B.II.1) or of ALS (C.III.1). METHODS: Patients underwent a single clinical assessment, MRI, and [(18)F]fluorodeoxyglucose PET brain scan. Neuropathologic examination and genetic analyses were carried out. RESULTS: Patients presented clinically with the behavioral variant of FTD. Language dysfunctions were marked with comprehension being particularly affected. Neuroimaging revealed frontotemporal atrophy and glucose hypometabolism, with predominant left-side involvement, in Patients A.III.1 and B.II.1. Subject C.III.1 displayed mild atrophy and symmetric anterior hypometabolism. All patients were neuropathologically diagnosed with FTLD-U. Ub-ir NII were noted in Patients A.III.1 and B.II.1 but were absent in Patient C.III.1. The following PGRN sequence variations were found: IVS6-2A-->G (A.III.1), R493X (B.II.1), and R433W (C.III.1). IVS6-2A-->G may lead to skipping of exon 7 with consequent frameshift of the coding sequence and premature termination of PGRN translation. CONCLUSIONS: We have found two PGRN mutations associated with FTD, in affected individuals who are members of families with possible autosomal dominant FTD. A third PGRN sequence variation (R433W) was found in an FTD patient with family history of ALS.

Adult↗
PubMed2006

Distribution of putative adhesins in Shiga toxin-producing Escherichia coli (STEC) strains isolated from different sources in Chile.

The distribution of three putative adhesin genes in 123 Shiga toxin-producing (STEC) strains was determined by PCR. The STEC strains were isolated from human patients (n=90) and food (n=33) and were characterized by serogroup, virulence markers (eae, stx(1), stx(2)) and adherence factors (efa1, lpfA(O157), saa) genes. Serogroups O157 (64.4%) and O26 (28.8%) were the most frequent among human strains and the majority (60.6%) of food strains were serologically non-typable. The adhesin genes efa1 (90%) and lpfA(O157) (73.3%) were the most common in humans strains and saa (45.5%) in food strains. The presence of these genes in addition to eae in STEC from different sources may suggest a relevant role in their pathogenesis.

Adhesins, Bacterial↗
PubMed2006

Isolation of Besnoitia besnoiti from infected cattle in Portugal.

Besnoitia besnoiti, an obligate intracellular protozoan parasite belonging to the phylum apicomplexa, is the causative agent of bovine besnoitiosis. Besnoitiosis is responsible for significant losses in the cattle industry of Africa and Mediterranean countries due to the high morbidity rate, abortion and infertility in males. The acute stage of disease is associated with the proliferative forms (tachyzoites) and is characterized by fever, whimpery, general weakness and swelling of the superficial lymph nodes. During the following chronic stage, a huge number of cysts are formed mainly in the subcutaneous tissues. This process is non-reversible, and chronic besnoitiosis is characterized by hyper-sclerodermia, hyperkeratosis, alopecia and, in bulls, atrophy, sclerosis and focal necrosis that cause irreversible lesions in the testis. In this paper we report on the identification of large cysts in the skin of a cow and a bull in Portugal, which presented loss of hair and enlargement and pachydermis all over the body. The observation of a two-layered cyst wall within the host cell, the encapsulation of the host cell by a large outer cyst wall, and the subcutaneous localization of the cysts within the host, were characteristic for B. besnoiti. The parasites were isolated from the infected animals and successfully propagated in Vero cells without prior passages in laboratory animals. Morphological characterization of B. besnoiti tachyzoites and the amplification of the 149 bp segment from the internal transcribed spacer 1 (ITS1), aided with specific primers, confirmed the identification of B. besnoiti.

Animals↗
PubMed2006

Immunodiagnosis of Besnoitia besnoiti infection by ELISA and Western blot.

Besnoitia besnoiti, an obligate intracellular apicomplexan protozoan parasite, is the causative agent of bovine besnoitiosis. This infection may dramatically affect body condition and lead to irreversible infertility in males, resulting in important economical losses in livestock production. Identification of serologically positive animals is of major relevance to elaborate appropriate measures of control. While identification of clinical cases is relatively easy to carry out, the finding of subclinical forms of infection is more difficult, thus serology is considered as an appropriate diagnostic tool. In view to improve and validate immunodiagnosis, we evaluated an enzyme-linked immunosorbent assay (ELISA), complemented with a Western blot (both using a somatic B. besnoiti-tachyzoite antigen) to detect anti-B. besnoiti antibodies in bovine sera. The comparative evaluation of the 2 methods, using 13 sera from animals affected by the chronic phase of besnoitiosis and 10 asymptomatic carriers, yielded a diagnostic sensitivity of 87% for ELISA and 91% for Western blot analyses. Specificity was tested with sera from animals with confirmed Toxoplasma gondii (n=5) and Neospora caninum (n=12) infection, and with 64 negative sera from either an endemic or a non-endemic area. The ELISA specificity ranged between 96.4% and 98%, the Western blot specificity between 96.4% and 100%. The present study demonstrated that ELISA and Western blot, using in vitro generated somatic B. besnoiti antigen, is a useful tool combination to reliably detect animals that have been exposed to B. besnoiti infection, including both asymptomatic and symptomatic courses of disease.

Animals↗
PubMed2006

Comparison between a GnRH antagonist and a GnRH agonist flare-up protocol in oocyte donors: a randomized clinical trial.

BACKGROUND: Little information is available on the outcome of controlled ovarian hyperstimulation (COH) using GnRH antagonist in oocyte donation cycles especially in comparison with the short GnRH agonist protocol. This study was aimed at comparing the two stimulation protocols in oocyte donation (OD) cycles. METHODS: A total of 113 donors randomly received COH using either GnRH antagonist or GnRH agonist. The primary endpoint was the mean number of mature oocytes retrieved per started donor cycle. Secondary endpoints were the mean number of cumulus-oocyte-complexes (COCs) retrieved, the mean proportion of mature oocytes, pregnancy and implantation rates in recipients. RESULTS: Oocytes were distributed to 166 recipients. The mean number (+/- SD) of COC (11.6 +/- 5.8 versus 12.1 +/- 6.7), mature oocytes (8.4 +/- 4.4 versus 8.9 +/- 5.3) and the proportion of mature oocytes (70.8 versus 75.7%) retrieved per started donor cycle were similar in the antagonist and agonist groups, respectively. The implantation rate (26.1 versus 30.1%), clinical (40.2 versus 45.6%) and ongoing pregnancy rate per recipient cycle (32.2 versus 37.9%) were comparable in antagonist and agonist protocols, respectively. CONCLUSIONS: Similar mean number of mature oocytes and comparable pregnancy rates are achieved after OD in which donors received COH using GnRH antagonist or short GnRH agonist protocols.

Adult↗
PubMed2006

Routine use of pleural fluid cultures. Are they indicated? Limited yield, minimal impact on treatment decisions.

In pleural infection, it has been recommended that Gram stain and cultures should be obtained on a routine basis. However, this recommendation has not been tested prospectively. We evaluated the yield of microbiological studies in 259 patients with parapneumonic pleural effusion. Microbiological studies were positive on the pleural fluid of 50 patients (19.3%). In 48 of the 50 patients with positive microbiological results (96%), the need for pleural drainage was correctly predicted by pleural fluid parameters. There were no differences in hospital stay (9.5+/-2.5 days versus 9.9+/-3.2 days, P=0.68) or in mortality (2 deaths in each group, P=0.58) between the group of patients in which antibiotic treatment was changed according to microbiological results and the group of patients in which it is not. In conclusion, this study demonstrates that, at least in our institution, routine microbial investigation of pleural fluid adds very little to the standard management of parapneumonic effusions.

Adult↗
PubMed2005

A mutation in myotilin causes spheroid body myopathy.

BACKGROUND: Spheroid body myopathy (SBM) is a rare, autosomal dominant, neuromuscular disorder, which has only been previously reported in a single large kindred. Identification of the mutated gene in this disorder may provide insight regarding abnormal neuromuscular function. METHODS: The authors completed a detailed clinical evaluation on an extensive kindred diagnosed with SBM. Genome-wide linkage analysis was performed to localize the disease gene to a specific chromosomal region. Further marker genotyping and screening of a positional, functional candidate gene were completed to detect the disease-causing mutation. Pathologic analysis of muscle biopsy was performed on three individuals. Biochemical studies were performed on one muscle biopsy specimen from an affected individual. RESULTS: Linkage to chromosome 5q23-5q31 was detected with a lod score of 2.9. Genotyping of additional markers in a larger sample of family members produced a maximum lod score of 6.1 and narrowed the critical interval to 12.2 cM. Screening of the candidate gene titin immunoglobulin domain protein (TTID, also known as MYOT) detected a cytosine-to-thymine mutation in exon 2 of all clinically affected family members. Similar pathologic changes were present in all muscle biopsy specimens. Immunohistologic and biochemical analysis revealed that the TTID protein, also known as myotilin, is a component of the insoluble protein aggregate. CONCLUSIONS: A novel mutation in the TTID gene results in the clinical and pathologic phenotype termed "spheroid body myopathy." Mutations in this gene also cause limb-girdle muscular dystrophy 1A and are associated with myofibrillar myopathy.

Adult↗
PubMed2005

Oocyte donation in patients with Turner's syndrome: a successful technique but with an accompanying high risk of hypertensive disorders during pregnancy.

BACKGROUND: Few data are available on pregnancy rate and obstetrical outcome after oocyte donation in Turner's syndrome patients. We conducted a retrospective analysis on the outcome of this subgroup. METHODS: Thirty oocyte donation cycles with fresh embryo transfer were performed in 21 patients between 2001 and 2004. RESULTS: The mean (+/-SD) age of the recipients was 33.1+/-1.8 years. The median (range) number of transferred embryos per cycle was two (1-4). Seventeen pregnancies were obtained (57%), of which 12 were clinical (40%). The implantation rate and the ongoing pregnancy rate were 22% (15 out of 68) and 30% (nine out of 30), respectively. Premature delivery was observed in 50% (four out of eight) of the pregnancies and intrauterine growth retardation in 55.5% (five out of nine) of the fetuses. Hypertensive disorders occurred in five out of eight pregnancies (three pre-eclampsias). CONCLUSIONS: Turner's syndrome patients achieve acceptable pregnancy rates after oocyte donation. A high rate of pregnancy-associated hypertensive disorders was observed which have led to a high rate of prematurity and intrauterine growth restriction. Although the number of cases in this study is limited, these results call for the need for intensive surveillance of such pregnancies. In order to reduce the risk of hypertensive disorders induced by multiple pregnancies, single embryo transfer should be proposed.

Adult↗
PubMed2005

Characterization of six marker chromosomes by comparative genomic hybridization.

We applied comparative genomic hybridization (CGH) in six patients with de novo prenatal or postnatal extra marker chromosomes (MC). In four cases, MCs were mosaic and in one of them, the MC was detected in less than 50% of the cells. In three cases, CGH identified the origin of the extra MCs. In the other three, two prenatal cases and one child with an abnormal phenotype, CGH showed normal profiles. Among these cases, a normal profile and entirely C-band positive was identified suggesting that MC did not contain euchromatin. Genetic imbalances detected by CGH were as follow: a gain of 8p10-p12 in a boy with facial dysmorphism, hyperactivity and speech delay, a gain of 8q10-q12 in a healthy man with a history of spontaneous abortions, and a gain of 15q11-q13 in a girl with speech delay, and motor skill and object manipulation difficulties. Clinical data of these patients were compared with those reported in the literature. We conclude that CGH is a very useful and powerful tool for characterizing prenatal or postnatal MCs, even when the mosaicism is present and the MCs are present in less than 50% of the cells.

Adolescent↗
PubMed2005

[Prognostic value of syncope in the presentation of pulmonary embolism].

OBJECTIVE: Although the prognostic value of syncope has not been specifically addressed, it has generally been considered an indicator of poor prognosis in pulmonary embolism. The objective of this study was to carry out a prospective evaluation of the risk of recurrence and/or death in patients with pulmonary embolism that presents with syncope. PATIENTS AND METHODS: A total of 168 patients had a confirmed diagnosis of pulmonary embolism. Twelve were lost to follow up and did not enter statistical analysis. The mean follow-up period was 5 months. RESULTS: The prevalence of syncope in the patients studied was 22%. Of the 34 patients who presented syncope, objectively confirmed recurrence occurred in 2 (5.9%). In the patients who did not present syncope, recurrence was confirmed in 8 (6.6%; P=.8). Death occurred in 2 patients (5.9%) from the group presenting syncope and 15 (12.3%) from the remaining patients in the series (P=.4). The relative risk of recurrence and/or death associated with presentation of syncope was 0.5 (95% confidence interval, 0.2-1.8). A similar risk was obtained following adjustment for the presence or absence of cancer or deep vein thrombosis. CONCLUSIONS: Patients with pulmonary embolism that presents with syncope do not have an increased risk of recurrence and/or death.

Aged↗
PubMed2005

Results of a case-detection programme for alpha1-antitrypsin deficiency in COPD patients.

Alpha1-antitrypsin (alpha1-AT) deficiency is an underdiagnosed condition in patients with chronic obstructive pulmonary disease (COPD). The present authors have conducted a nationwide case detection programme of alpha1-AT deficiency in unselected patients with COPD using dried blood spots. The first phase analysed samples from 971 patients by determining alpha1-AT concentrations and identifying the deficient Z allele by genotyping using rapid real-time PCR. The second phase analysed 1,166 samples with alpha1-AT concentrations and identified both the S and the Z allele, but only in samples with low alpha1-AT concentrations. A total of eight (0.37%) individuals with the severe deficiency PiZZ were detected. In addition, three patients were identified with the PiSZ genotype in the second phase (0.3%). The global cost of the programme was 41,512, which represents 19.42 per sample and 5,189 per PiZZ detected. A sensitivity analysis demonstrated that performing Z genotype to all samples would have resulted in increased costs of 28 per sample and 7,479.5 per PiZZ case identified. In conclusion, a case detection programme of alpha1-antitrypsin deficiency in patients with chronic obstructive pulmonary disease using dried blood spots is feasible and at a reasonable cost per case detected. Diagnostic yield and costs depend largely on inclusion criteria and the protocol for processing of samples.

Adult↗
PubMed2005

Severe hepatotoxicity due to anti-tuberculosis drugs in Spain.

OBJECTIVES: To determine the frequency of severe hepatotoxicity due to anti-tuberculosis (TB) drugs, and predictors of development of acute liver failure or of death. METHODS: A retrospective study conducted by members of the Spanish Society of Pneumology from 18 hospitals during 1997-2001. A case of severe hepatotoxicity was defined as any asymptomatic patient with a ten-fold increase in transaminases or three-fold increase in colostasis parameters, or, among patients with hepatitis symptoms, any raised hepatic parameters or development of hepatic failure. Predictive factors were studied using logistic regression, calculating odds ratios (OR) and their 95% confidence intervals (CI). RESULTS: One hundred and six patients developed severe hepatotoxicity. Of a total of 3510 patients, 90 were treated for active TB (2.56%). Eleven cases (10.3%) presented with acute liver failure, three of whom underwent liver transplant. The global case fatality rate was 4.7% (five cases, three associated with alcohol use or hepatotoxic drugs). The predictors of poor prognosis were total bilirubin > 2 mg/dl (OR 9.4, 95% CI 1.0-85.5) and serum creatinine > 1.5 mg/dl (OR 32.1, 95% CI 2.4-424.6). CONCLUSIONS: Severe hepatotoxicity due to anti-tuberculosis drugs is associated with a high fatality rate. Prevention should be based on informing patients and frequent clinical and laboratory controls.

Adult↗
PubMed2004

Intracellular ferritin accumulation in neural and extraneural tissue characterizes a neurodegenerative disease associated with a mutation in the ferritin light polypeptide gene.

Abnormal accumulation of ferritin was found to be associated with an autosomal dominant slowly progressing neurodegenerative disease clinically characterized by tremor, cerebellar ataxia, parkinsonism and pyramidal signs, behavioral disturbances, and cognitive decline. These symptoms may appear sequentially over a period of 4 decades. Pathologically, intranuclear and intracytoplasmic bodies were found in glia and subsets of neurons in the central nervous system as well as in extraneural tissue. Biochemical analyses of these bodies isolated from the striatum and cerebellar cortex revealed that ferritin light polypeptide (FTL) and ferritin heavy polypeptide (FTH1) were the main constituents. Molecular genetic studies revealed a 2-bp insertion mutation in exon 4 of the FTL gene. The resulting mutant polypeptide is predicted to have a carboxy terminus that is altered in amino-acid sequence and length. In tissue sections, the bodies were immunolabeled by anti-ferritin and anti-ubiquitin antibodies and were stained by Perls' method for ferric iron. Synthetic peptides homologous to the altered and wild-type carboxy termini were used to raise polyclonal antibodies. These novel antibodies as well as an antibody recognizing FTH1 immunolabeled the bodies. This study of this disorder has provided additional knowledge and insights in the growing area of ferritin-related neurodegeneration.

Adult↗
PubMed2004

Effect of exacerbations on quality of life in patients with chronic obstructive pulmonary disease: a 2 year follow up study.

BACKGROUND: A study was undertaken to evaluate exacerbations and their impact on the health related quality of life (HRQL) of patients with chronic obstructive pulmonary disease (COPD). METHODS: A 2 year follow up study was performed in 336 patients with COPD of mean (SD) age 66 (8.2) years and mean (SD) forced expiratory volume in 1 second (FEV(1)) 33 (8)% predicted. Spirometric tests, questions regarding exacerbations of COPD, and HRQL measurements (St George's Respiratory Questionnaire (SGRQ) and SF-12 Health Survey) were conducted at 6 month intervals. RESULTS: A total of 1015 exacerbations were recorded, and 103 (30.7%) patients required at least one hospital admission during the study. After adjustment for baseline characteristics and season of assessment, frequent exacerbations had a negative effect on HRQL in patients with moderate COPD (FEV(1) 35-50% predicted); the change in SGRQ total score of moderate patients with > or =3 exacerbations was almost two points per year greater (worse) than those with <3 exacerbations during the follow up (p = 0.042). For patients with severe COPD (FEV(1) <35% predicted) exacerbations had no effect on HRQL. The change in SGRQ total score of patients admitted to hospital was almost 2 points per year greater (worse) than patients not admitted, but this effect failed to show statistical significance in any severity group. There was a significant and independent seasonal effect on HRQL since SGRQ total scores were, on average, 3 points better in measurements performed in spring/summer than in those measured in the winter (p<0.001). CONCLUSIONS: Frequent exacerbations significantly impair HRQL of patients with moderate COPD. A significant and independent effect of seasonality was also observed.

Adult↗
PubMed2003

[Screening program for alpha-1 antitrypsin deficiency in patients with chronic obstructive pulmonary disease, using dried blood spots on filter paper].

Alpha-1 antitrypsin (AAT) deficiency is an under-diagnosed disease and screening programs have therefore been recommended for patients with chronic obstructive pulmonary disease (COPD). We present the results of the pilot phase of a screening program for AAT deficiency in order to evaluate the technique used, the procedures for transporting samples and the results obtained. Over a period of one month, five centers collected samples from all COPD patients for whom plasma concentrations of AAT or Pi phenotype had not yet been determined. Capillary blood spots were dried on filter paper and then sent by surface mail to a central laboratory for study. An immunonephelometric assay was used to determine AAT and DNA phenotyping was done by use of a Light Cycler. Samples were analyzed from 86 COPD patients (76 men, 10 women) with a mean age of 68.2 years. AAT deficiency was ruled out for 74 patients (86%) who had concentrations above the cutoff established, although one of them was MZ heterozygote by genotype. Among the 12 remaining patients (13.9%), only two also had a Z allele. The rest were individuals with concentrations below the established threshold and no evidence of a Z allele (10 patients, 11.6%). The Z allele frequency observed (3/172; 1.74%) was very similar to that found in the general population. The results of this pilot study allowed us to confirm that the method used to collect samples worked well. The sampling method is applicable, easy and well-accepted by participating physicians. It allowed AAT concentrations and Z allele deficiency to be determined. The method correlates well with standard techniques used for samples in whole blood.

Aged↗
PubMed2003

Hippocampal infection with HSV-1-derived vectors expressing an NMDAR1 antisense modifies behavior.

Herpes simplex virus-derived amplicon vectors simultaneously expressing the open reading frame encoding NR1 subunit of the NMDA receptor, either in sense or antisense orientation, as well as the open reading frame encoding the green fluorescent protein (GFP), as distinct transcription units, were constructed. Vector expression in cells was demonstrated by GFP-fluorescence, immunofluorescence, Western blots and RT-PCR. The vectors were inoculated into the dorsal hippocampus of adult male rats, which were then trained for habituation to an open field and for inhibitory avoidance to a foot-shock. Those animals injected with vectors expressing NR1 protein showed habituation to a new environment, and achieved the criteria for a step-down inhibitory avoidance to a foot-shock. In contrast, animals injected with vectors carrying the NR1 open reading frame in antisense position, showed neither habituation nor appropriate performance in the inhibitory avoidance task. There was no evidence for motor impairment or motivational disturbance, since all the animals exhibit similar behavior and performance in the training sessions. Hence, the impaired performance might be due to either amnesia or disability to record events. Transgene expression in brain, as revealed by GFP fluorescence, was mainly observed in pyramidal cells of CA1, but also in CA3. Therefore, our results strongly support the participation of hippocampal NR1 subunit in habituation to a new environment, but also in recording events for the inhibitory avoidance task. Hence, amplicon vectors appear to be useful tools to modify endogenous gene expression at a defined period, in restricted brain regions, and should allow investigating in vivo functions of genes.

Animals↗