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B Romero

Publications and source records attributed to B Romero.

At least 19 recordsLinked to original sources
PubMed2006

Molecular epidemiology of Types I/III strains of Mycobacterium avium subspecies paratuberculosis isolated from goats and cattle.

Molecular characterization of Mycobacterium avium subsp. paratuberculosis (M. a. paratuberculosis) isolates classifies them into three groups: cattle or Type II, sheep or Type I, and intermediate or Type III. To avoid problems associated with characterization of extremely slow growth strains, PCR-based techniques that divide the M. a. paratuberculosis strains in two main groups (cattle or Type II, and sheep or Types I/III) can be performed. The objectives of this study were to characterize the M. a. paratuberculosis isolates identified by different PCR-based tests (IS1311-PCR and restriction endonuclease analysis, PCR test based on a DNA sequence difference, and a PCR aimed at three Type I-specific loci), and to determine the clinical and epidemiological implications of Types I/III M. a. paratuberculosis strains in livestock. One hundred and fifty-eight M. a. paratuberculosis strains from domestic ruminants were analyzed. One hundred and six M. a. paratuberculosis isolates (61 from goats and 45 from cattle) were classified as Type II strains; and 52 (29 from cows, 20 from goats, and three from sheep) were included in the Types I/III. The Types I/III M. a. paratuberculosis strains were associated to Spanish native breeds. The majority of these animals had not been in direct or indirect contact with sheep flocks infected with M. a. paratuberculosis. This fact should be taken into account when implementing paratuberculosis control programs.

Animals↗
PubMed2005

[Nightmares in patients with Alzheimer's disease caused by donepezil. Therapeutic effect depends on the time of intake].

Dementia of the Alzheimer type (DAT) has been linked to losses of cholinergic function in the brain. The acetylcholinesterase inhibitors donepezil, rivastigmine and galantamine improve cognitive performance in manifest dementia. These substances, however, also influence the quality of sleep, and particularly the quality and amount of dreams. We therefore investigated the influence of the time point of donepezil intake on the occurrence of nightmares. We observed a clear-cut relationship between the occurrence of nightmares and an evening dose of donepezil in eight patients with DAT. None of these patients reported nightmares when donepezil was taken in the morning. We suggest that the activation of the visual association cortex during REM sleep is enhanced by donepezil, a mechanism most likely facilitating the development of nightmares in patients with DAT.

Aged↗
PubMed2004

Release of inflammatory mediators in irradiated cell salvage blood and their biological consequences in human beings following transfusion.

BACKGROUND AND OBJECTIVE: Irradiation of intraoperative cell salvage blood has recently been used to inactivate tumour cells before retransfusion, during cancer surgery. No information is available about a potential inflammatory response of the recipient to the retransfusion of irradiated intraoperative cell salvage blood. This pilot study was conducted to investigate the possible release of the pro-inflammatory mediators, tumour necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), eotaxin and monocyte chemo-attractant protein-1 (MCP-1), in the serum of recipients by intraoperative retransfusion of irradiated intraoperative cell salvage blood. METHODS: Nine patients undergoing gynaecological cancer surgery were included in this study. Intraoperative cell salvage blood was irradiated with 50 Gy and retransfused to the patient. Serum and intraoperative cell salvage blood concentrations of TNF-alpha, IL-1beta, eotaxin and MCP-1 were repeatedly analysed before and after retransfusion, respectively before and after irradiation. RESULTS: Traces of mediators were detected in intraoperative cell salvage blood but no increase due to irradiation was observed. Following transfusion of intraoperative cell salvage blood, minute quantities (all < 30 pg mL(-1) of mediators were detected in the serum of patients. However, there was no significant upregulation compared to serum values before retransfusion. CONCLUSIONS: These results provide evidence that retransfusion of irradiated intraoperative cell salvage blood might represent a blood-saving strategy in cancer surgery without an immunological inflammatory response as shown by a lack of upregulation of inflammatory mediators.

Aged↗
PubMed2003

[German-speaking memory clinics: state of the art and practical recommendations].

The 7th annual meeting of the memory clinics of Germany, Switzerland and Austria in March 2002 in Göttingen, Germany was an optimal opportunity to make an inventory about the state of the art in diagnostic and therapy of dementia and mild cognitive impairment in German-speaking memory clinics. Several problems were discussed including difficulties in 1) diagnosis of patients with aphasia or foreign patients, 2) handling of demented patients without a caregiver, 3) psychological support for patients, who have been diagnosed in a very early stage, 4) misunderstandings between general practitioners, neurologists and psychiatrists in private practice on the one hand and the memory clinics on the other hand, 5) recommendations for prevention of dementia, 6) recommendations concerning dementia and car driving and 7) questions of genetic counselling. The following paper is a summary of the results of a workshop in Göttingen and gives practical recommendations based on the experiences of the memory clinics.

Aged↗
PubMed2003

Molecular brain imaging and the neurobiology and genetics of schizophrenia.

It has been hypothesized that schizophrenia is related to dysfunction in temporolimbic-prefrontal neuronal networks, which is acquired early in an individual's development. After puberty, relatively reduced prefrontal control of striatal dopaminergic neurotransmission may lead to unmodulated striatal dopamine (DA) activity, and the positive symptoms of acute psychosis. Brain imaging studies support the notion of prefrontal dysfunction in schizophrenia and correlated upregulation of presynaptic striatal DA activity. Recent molecular brain imaging studies have combined genetic assessments with a multimodal neuroimaging approach to further refine our understanding of the pathophysiologic architecture of the disorder. We review the literature on functional brain imaging in schizophrenia and discuss genotype effects on core psychotic symptoms. A promising research strategy is the identification of genetic and environmental factors that contribute to intermediate phenotypes such as working memory deficits in schizophrenia. Molecular brain imaging can help to unravel the complex interactions between genes and environment and its association with neuronal network dysfunction in schizophrenia.

Animals↗
PubMed2003

[Self-esteem in Mexican pediatric patients on peritoneal dialysis and kidney transplantation].

It has been reported in literature that self-esteem increases in patients who pass from continuous ambulatory peritoneal dialysis to renal transplantation. However, our clinical observations in the Department of Nephrology of Hospital Infantil de México Federico Gómez indicate otherwise. Therefore, we carried out this research on 60 patients, children and adolescents, male and female between the ages from 8 to 15 years old, and we applied them the Coopersmith self-esteem questionnaire, which has been validated in mexican population. These findings indicate that the social environment continuous ambulatory peritoneal dialysis patients feel more adapted than patients in renal transplant (p = 0.05). However it was also observed that these patients tried to show a better image on their situation through compensatory mechanisms (defense p = 0.03). It was concluded that it would be necessary to follow the adaptation of the transplanted patients, in order to help them achieve complete rehabilitation.

Adaptation, Psychological↗
PubMed2002

[Concept and effectiveness of a treatment program for patients with dementia and their relatives. Results from the Bad Aibling Alzheimer Disease Therapy Center].

A short-term residential treatment programme designed to prepare patients with dementia and caregivers for life with a progressive disease was evaluated in a pre-treatment post-treatment design. The multicomponent programme included: 1) intensive rehabilitation for patients, based on the concept of Self-Maintenance Therapy, and 2) an intervention programme for caregivers. Based on the concept of Self-Maintenance Therapy, it was hypothesised that experiences which are in accordance with patients' self-system would support patients' well-being, reduce psychopathological symptoms and facilitate social participation. In this study treatment effects in FTLD are analysed and compared with treatment effects in AD. The results for both groups show a consistent improvement in patients' depression and in other psychopathological symptoms, which can be seen as directly beneficial for patients. Following treatment, caregivers also felt less depressed, less mentally fatigued and restless, and more relaxed. It was predicted that FTLD patients challenge caregivers in a different way compared to patients with AD due to the particular profile of cognitive and psychiatric problems but there are no significant differences between groups. Further controlled follow-up studies are needed to evaluate the effects of the intervention as dementia progresses and to address hypotheses about factors responsible for benefits as well as for treatment resistance.

Adaptation, Psychological↗
PubMed2002

Reproducibility of sequential head-up tilt testing in patients with recent syncope, normal ECG and no structural heart disease.

AIMS: To assess the reproducibility of the response to sequential head-up tilt tests. METHODS AND RESULTS: A head-up tilt test was performed early after syncope in 127 patients with a normal ECG and no structural heart disease. Patients with a positive response (82 patients) were randomized to two (1 week and 2 weeks later) or one (2 weeks later) additional head-up tilt tests, and patients with a negative response (45 patients) were randomized to a second head-up tilt test 1 or 2 weeks after the first. The reproducibility of a positive response in the second head-up tilt test was 80% after 1 week and 53% after 2 weeks (P<0.01). Only 53% of the patients with a positive response to a first and second head-up tilt test had a positive response to a third (P=0.01). Intra-individual variation in the time to a positive response was wide. The reproducibility of the cardioinhibitory responses was very poor. Reproducibility of a negative response was 80%. CONCLUSIONS: In patients with recent syncope, the rate of positive responses decreases with sequential head-up tilt tests. Furthermore, the time to a positive response in different head-up tilt tests shows important intra-individual variations, and the reproducibility of the cardioinhibitory responses is very poor. In contrast, the reproducibility of the negative responses is high.

Adolescent↗
PubMed2002

[Chronic ethanol feeding induces oxidative stress in the optic nerve of rats].

PURPOSE: To assess the involvement of oxidative stress in optic nerves after chronic intake of ethanol in adult rats, when compared to animals fed with an ethanol-free isocaloric diet. METHODS: Male Sprague-Dawley rats were used throughout the study. They were fed an ethanol-containing liquid diet, whereas the pair-fed group was given an ethanol-free isocaloric diet. After six weeks of the experiment, optic nerves were extracted and markers of oxidative stress were assayed, i.e., antioxidants such as glutathione and lipid peroxidation products such as malondialdehyde (MDA). RESULTS: The GSH content in the optic nerves of ethanol-fed animals was significantly reduced, and the concentration of MDA was significantly higher in this group when compared with the pair-fed group. Time-course of body weight of animals in both groups varied identically throughout the six weeks of the experiment. CONCLUSION: The increase in lipid peroxidation products (MDA), together with the decrease in cellular antioxidants (GSH) confirm, in this experimental model, the involvement of oxidative stress in ethanol-induced toxicity of the optic nerves of rats. In view of the body weight time course, the influence of nutritional status on the parameters studied could also be discarded (Arch Soc Esp Oftalmol 2002; 77: 263-268).

Animals↗
PubMed2001

Development of a homologous transformation system for the opportunistic human pathogen Aspergillus fumigatus based on the sC gene encoding ATP sulfurylase.

The development of a homologous transformation system for the opportunistic human pathogenic fungus Aspergillus fumigatus is described. The system is based on the sC gene encoding ATP sulfurylase. Several A. fumigatus sC mutant strains were readily isolated by strong selection for selenate resistance. The coding region plus upstream and downstream regulatory sequences of the A. fumigatus sC gene were cloned by inverse PCR and then sequenced. Sequencing of the sC cDNA revealed the presence of five introns located within the first half of the gene. The A. fumigatus sC gene encodes a protein of 574 amino acids which is highly similar to ATP sulfurylases from the filamentous fungal species Aspergillus nidulans, Aspergillus terreus and Penicillium chrysogenum. By contrast, ATP sulfurylases from the yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe lack the C-terminal adenosine-5'-phosphosulfate kinase-like domain present in the filamentous fungal orthologues. A 3.8-kb DNA fragment amplified by PCR and containing the sC gene plus 5' and 3' flanking regions was cloned into pUC19 to give the vector pSCFUM. Transformation of two different sC mutant isolates with the plasmid pSCFUM established the functionality of this new homologous transformation system. Molecular analysis of sC+ transformants showed that up to 44% of transformed clones contained one or more copies of the entire plasmid integrated at the sC locus. This result also demonstrates the utility of the sC marker for targeting specific genetic constructs to the A. fumigatus sC locus, facilitating studies of gene regulation and function.

Amino Acid Sequence↗
PubMed2000

Beta-amyloid-induced activation of caspase-3 in primary cultures of rat neurons.

It is known that beta-amyloid peptide (Abeta) contributes to the neurodegeneration in Alzheimer's disease (AD) and operates through activation of an apoptotic pathway. Apoptotic signal is driven by a family of cysteine proteases called caspases. The beta-amyloid precursor protein (APP) is directly and efficiently cleaved by caspases during apoptosis, resulting in elevated beta-amyloid peptide formation. Cerebellar neurons from rat pups were treated with the aged Abeta(25-35) at 1 and 5 microM and fluorescence assays of caspase activity performed over 4 days. We observed an increase in caspase activity after 48 h treatment in both 1 and 5 microM treated cells, then (72-96 h) caspase activity decreased to control values. The data presented support the hypothesis that Abeta(25-35)-induced apoptosis is mediated by the activation of Caspase-3 and that this is a transient effect.

Amyloid beta-Peptides↗
PubMed2000

Reduction of brain antioxidant defense upon treatment with butylated hydroxyanisole (BHA) and Sudan III in Syrian golden hamster.

Treatment with the antioxidant butylated hydroxyanisole (BHA) or the azo dye Sudan III during two weeks led to changes in the brain enzymatic antioxidant defense of Syrian golden hamsters. BHA was able to induce liver superoxide dismutase (SOD) 2-fold but had no effect on the brain SOD activity, whereas SOD activity was reduced to 50% in brain and remained unchanged in liver with Sudan III. These two substances are known inducers of DT-diaphorase and in fact this enzymatic activity was induced 4- and 6-fold in liver with BHA and Sudan III, respectively. However, BHA promoted a significant 40% reduction, whereas no change was observed with Sudan III in brain DT-diaphorase activity. Glutathione(GSH)-related enzymatic activities were also assayed in brain and liver. No induction was observed with BHA or Sudan III for any of the activities tested in hamster brain: GSH S-transferase (GST), GSH peroxidase (GSH-Px) and glutathione disulfide (GSSG) reductase (GR). Only 1.3- and 1.4-fold increases of GST and GR activities were observed in liver and no change in any of these enzymatic activities in brain with BHA; a partial limitation of permeability to BHA of the blood-brain barrier may explain this results. Furthermore, Sudan III promoted reductions in all these GSH-related enzymatic activities in brain and liver. The possible explanations for these results are discussed.

Animals↗
PubMed1999

Perceived health over 3 years after percutaneous coronary balloon angioplasty.

The magnitude of the benefit of percutaneous transluminal coronary angioplasty (PTCA) in terms of quality of life depending on baseline and outcome clinical variables is not sufficiently understood because of the restrictive inclusion criteria of randomized clinical trials. The present study was designed to assess perceived health outcome at 3 years and its association with clinical variables after successful elective PTCA in a tertiary hospital throughout a prospective cohort study. Questionnaires were administered on the day before the procedure and 1 month and 3.4 years later (as mean follow-up) to 106 patients recruited during a 15-month period. Mean perceived health scores improved significantly for the population as a whole 1 month after PTCA, and improvement was maintained at the end of follow-up. The magnitude of the effect was different depending on clinical subgroups: (a) It was greatest in patients free from angina, myocardial infarction, or new revascularization procedures at the end of follow-up; (b) It was moderately reduced in patients with comorbidity; (c) Patients who reported to have dyspnea or angina at rest after the latest revascularization procedure did not improve, with poor final perceived health scores. Elective PTCA is associated with a significant improvement in perceived health, which varies depending on the clinical outcome. Comorbidity and initial perceived health influence outcome but do not preclude improvement.

Adult↗
PubMed1999

Clinical usefulness of head-up tilt test in patients with syncope and intraventricular conduction defect.

Head-up tilt test was performed in 99 patients with syncope of unknown origin and intraventricular conduction defect. Twenty-five per cent had a positive response to tilt with reproduction of spontaneous clinical symptoms. Holter recording revealed paroxysmal atrioventricular (AV) block in three patients. Carotid sinus massage was positive in four patients. An electrophysiological study was performed in 76 patients with abnormal findings in 17 (22%). Thus, vasovagal syncope was the discharge diagnosis in 25 patients (25%). Therefore, tilt test should be considered in patients with intraventricular conduction defect presenting with syncope of unknown origin, especially if clinical findings suggest the possibility of a vasovagal mechanism, or if the results of the electrophysiological study are inconclusive.

Adolescent↗
PubMed1998

Serum malondialdehyde: possible use for the clinical management of chronic hepatitis C patients.

Serum lipid peroxidation products are increased in inflammatory liver disease and, as we previously reported, also in chronic hepatitis C. We have performed a specific assay of malondialdehyde, the reported most abundant product of lipid peroxidation, in serum of twenty four chronic hepatitis C patients, before, during, and after interferon treatment. Liver biopsies were performed in each patient before and after interferon treatment. The results show higher serum malondialdehyde values in chronic hepatitis C patients than healthy subjects (n = 68) before interferon treatment (p < .001). Mean value of serum malondialdehyde levels after interferon treatment was significantly lower than before it (p < .002). Associating the histopathological findings in each of the 48 biopsies performed, with serum malondialdehyde and alanine aminotransferase activity levels, of the sample obtained the same day of biopsy, a much better correspondence with the histopathological severity was observed for malondialdehyde concentration than for alanine aminotransferase activity. These levels decreased significantly after interferon treatment. However, when the patients were grouped in responding (group I; n = 9) and non-responding (group II; n = 15) to interferon treatment, according to the histopathological findings before and after interferon, the values of group I before interferon treatment were significantly higher than group II (p < .03). Thus, a potential predictive value could be ascribed to the serum malondialdehyde levels before interferon treatment in these patients. We propose the utility of the specific assay of malondialdehyde for the clinical management of chronic hepatitis C patients.

Adult↗
PubMed1998

Lipid peroxidation products and antioxidants in human disease.

Lipid peroxidation (LPO) is a free radical-related process that in biologic systems may occur under enzymatic control, e.g., for the generation of lipid-derived inflammatory mediators, or nonenzymatically. This latter form is associated mostly with cellular damage as a result of oxidative stress, which also involves cellular antioxidants in this process. This article focuses on the relevance of two LPO products, malondialdehyde (MDA) and 4-hydroxynonenal (HNE), to the pathophysiology of human disease. The former has been studied in human serum samples of hepatitis C virus-infected adults and human immunodeficiency virus-infected children. In these two cases it is shown that the specific assay of serum MDA is useful for the clinical management of these patients. The presence of MDA in subretinal fluid of patients with retinal detachment suggests the involvement of oxidative stress in this process. Moreover, we were able to report the dependence of this involvement on the degree of myopia in these patients. The assay of MDA contents in the peripheral nerves of rats fed a chronic alcohol-containing diet or diabetic mice also confirms the pathophysiologic role of oxidative stress in these experimental models. In these two cases, associated with an increase in tissue LPO products content, we detected a decrease of glutathione peroxidase (GSHPx) activity in peripheral nerve, among other modifications. We have demonstrated that in vitro HNE is able to inhibit GSHPx activity in an apparent competitive manner, and that glutathione may partially protect and/or prevent this inactivation. The accumulation of LPO products in the brain of patients with Alzheimer's disease has also been described, and it is on the basis of this observation that we have tried to elucidate the role of oxidative stress and cellular antioxidants in beta-amyloid-induced apoptotic cell death of rat embryo neurons. Finally, we discuss the possible role of the observed vascular effects of HNE on human arteries.

Adult↗
PubMed1998

Renal graft survival in children with early acute rejection.

Acute rejection episodes (AREs) are an important cause of morbidity and mortality in children following renal transplantation. For the purpose of this study, the diagnosis of early rejection was established when it developed within the first 6 months post-transplantation. The impact of an early ARE on patient and graft survival areas was studied in 44 patients who received their grafts between January 1987 and December 1995. Group I (GI) was comprised of 25 patients who developed 30 ARE. They were compared to 19 age- and sex-matched controls without ARE, group II (GII), who were transplanted during the same time-period and received similar long-term immunosuppressive triple therapy, oral prednisone, azathioprine and cyclosporine A. The ARE was confirmed by renal biopsy in 83% of the cases. Morbidity, mortality and graft function were assessed statistically at baseline, 12 and 24 months after transplantation. Seven GI patients lost their grafts during an ARE; in 4 cases death that was related to opportunistic infections presenting during or soon after anti-rejection therapy, whereas 3 patients who survived lost their grafts due to thromboses or infections, also as a consequence of ARE. The GI graft survival rates were 76% and 72% at 12 and 24 months post-transplant, respectively, whereas the graft survival rate of GII patients was 100% at both evaluation periods. The patient survival rate was 84% in GI and 100% in GII patients at 24 months. No statistically significant differences of renal function were found between and/or within groups at 12 and 24 months. Recipients of living related donor (LRD) and cadaveric donor (CD) kidneys were evaluated independently of the group to which they were allocated. The acute rejection ratio (number of AREs/number of transplants) was 0.61 in LRD and 0.38 in CD (differences non-significant). This study concludes that AREs are an important cause of patient and graft loss, with opportunistic infections being a major threat to be considered during aggressive anti-rejection therapy. The renal function was normal after long-term follow-up in both groups of patients, regardless of ARE.

Acute Disease↗