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Biomedical subjects

A Torres

Publications and source records attributed to A Torres.

At least 271 records · Page 15Linked to original sources
PubMed1999

Parietaria allergy in children.

Parietaria, a grassy plant belonging to the Urticaceae family which is commonly found in urban environments, tends to grow on fences, walls and soils with a high content in nitrogen. Since 1983 the Xarxa Aerobiologica de Catalunya (Catalonian Aerobiological Network) has been using Hirst and Court sensors to monitor the daily concentrations of its pollen with respect to the weather conditions (wind, rain, temperature) in various sites in Catalonia and the Balearic Islands. This pollen is present practically all year round in our area, mainly during cold, rainy and seaside areas. Studies at a pediatric level are scarce and this is why we reviewed our data in this field. The study included a total of 12,650 case histories of first time attendances to our Pediatric Allergology Unit; 449 children showed sensitivity to Parietal pollen. Exclusive sensitivity to Parietaria in this age group of 1 and 15 years olds tended to be very low. However, we observed that after initial preferential sensitization to domestic allergens, Parietal pollen became the most frequent cause of sensitivity as the patients grew older. Although rhinoconjunctival manifestations predominate, at least at a pediatric level, the implication of Parietal pollen as a cause of bronchial asthma cannot be ignored.

Adolescent↗
PubMed1999

Community-acquired pneumonia in the elderly.

The incidence of community-acquired pneumonia (CAP) in the elderly is higher compared to younger populations. In addition, pneumonia in the elderly is a life-threatening problem. As our demographics have changed, clinicians have developed a heightened interest in managing pneumonia in the elderly. The development of pneumonia in elderly patients differs from that in younger individuals due to a complex array of factors. (1) The organisms involved depend on the setting in which the pneumonia developed: either the nonhospitalized elderly patient with CAP or the institutionalized patient who develops nursing-home-acquired pneumonia. (2) Underlying comorbid conditions commonly exist in the elderly that affect the etiology and outcome of pneumonia. Overall, Streptococcus pneumoniae and Haemophilus influenzae are still the most common etiologies of pneumonia in the elderly. The true role of gram-negative bacilli remains unclear although these micro-organisms may be more common etiologic agents in nursing-home pneumonia. Some recent studies from Mediterranean areas have reported high rates of infection by Chlamydia pneumoniae, but the real role of this micro-organism has to be confirmed. Another important issue is that the presenting symptoms of pneumonia in the elderly can be subtle and sometimes difficult to recognize. Fever is frequently absent, and delirium or alteration of functional physical capacity may be the only manifestations. Mortality in the elderly with CAP is higher when compared to younger populations. However, this may be explained by the concomitant presence of comorbid conditions more than by age per se. This statement has to be kept in mind when considering hospital and, particularly, intensive care unit admissions. Finally, antibiotic pharmacokinetics in the elderly populations with CAP ought to be considered to avoid frequent side-effects and complications. Overall, antibiotic regimens in hospitalized elderly patients with CAP do not differ from other hospitalized CAP populations. An organized approach to assessing elderly patients with suspicion of pneumonia and an awareness of common pitfalls in the management of this pulmonary infection in this population are essential to improving outcomes.

Aged↗
PubMed1999

[Effects of experimental vasectomy on testicular structure: ultrastructural study].

We have performed experimental vasectomies in dogs in order to study effects of vas deferens ligature with close technique, on the testicular ultrastructure. We point out the existence of alterations: structural changes of the seminiferous epithelium, great extracellular spaces which are generated for the premature exfoliation of germinal cells, degeneration of the germinal shock cells, the appearance of immature germinal cells and multinucleate spermatids in every stages of the spermatogenesis, the fall of mature spermatozoid number, thickening of basal membrane, relative increase in the Sertoli's cells size as well as their phagocytic function, and existence of spermaphagos unfasted into tubular lumen. The Leydig's interstitial islets show an absolutely normal cellular and vascular configuration.

Animals↗
PubMed1999

Severe community-acquired pneumonia: how to assess illness severity.

The assessment of severity is one of the most important issues in the management of the patient with community-acquired pneumonia. If forms the basis of decisions about hospitalization or admission to an intensive care unit. Age, comorbid illness and vital sign abnormalities have been shown to represent the principal criteria of pneumonia severity. Severe community-acquired pneumonia is characterized by one or more of the following criteria: acute respiratory failure, haemodynamic compromise, severe sepsis and septic shock, multilobar radiographic infiltrates, plus some additional laboratory parameters (blood urea nitrogen > 7 mM, lactate dehydrogenase > 260 U.L-1 and low serum albumin at admission). Several sets of corresponding simple clinical and laboratory criteria have consistently been shown to have considerable potential in predicting death caused by pneumonia. It was recently found that the tentative definition of severe community-acquired pneumonia provided by the American Thoracic Society guidelines is highly sensitive but poorly specific. An alternative rule, defining severe pneumonia as the presence of two of three minor criteria (systolic blood pressure < 90 mmHg, multilobar involvement and arterial oxygen tension/inspiratory oxygen fraction < 250) or one of two major criteria (mechanical ventilation and septic shock), had a sensitivity of 78%, a specificity of 94%, a positive predictive value of 75% and a negative predictive value of 95%. When validated in an independent patient population, this rule may contribute to a more uniform definition of severe community-acquired pneumonia.

Age Factors↗
PubMed1999

Statistical considerations in the methodology of quantifying immunocompetent cells in tumors.

OBJECTIVE: To quantify immunocompetent cell (IC) density for different testicular tumors and antibodies and to verify if the results of the comparisons depend on the antibody used. STUDY DESIGN: T-lymphocytes were studied with CD3 and UCHL1 antibodies and macrophages with MAC387 and CD68 in 43 patients with seminomas, mature teratomas, immature teratomas and embryonal carcinomas of the testis. Counts were expressed as number of IC per square millimeter. RESULTS: Use of different antibodies produced significant differences in the IC cell number; moreover, in the case of macrophages, the tumor type sequence by increasing cell number was different according to the antibody used. CONCLUSION: These results suggest the existence of a statistical interaction between the type of tumor and antibody.

Antibodies, Neoplasm↗
PubMed1999

Increased levels of tissue factor mRNA in mononuclear blood cells of patients with primary antiphospholipid syndrome.

Antiphospholipid antibodies (aPL) may stimulate tissue factor (TF) expression in cultured endothelial cells and monocytes, but there are discrepancies as to the expression of TF in the patients with antiphospholipid syndrome (APS). By using reverse transcription and polymerase chain reaction amplification, we have analysed TF mRNA accumulation in freshly isolated mononuclear blood cells (MBC) of 14 patients with primary APS (PAPS) and six normal controls. TF mRNA accumulation was low or absent in uncultured MBC from all normal controls, but was elevated in uncultured MBC from nine of the patients as well as in normal MBC incubated with 100 ng/ml lipopolysaccharide (LPS). Mean levels of TF mRNA, as measured by densitometry, were higher in MBC from patients (N = 14) than in those from controls (N = 6, P = 0.009), and in MBC from patients with a history of thrombosis (N = 9) than in those from patients without thrombosis (N = 5, P = 0.02). Uncultured MBC of patients with thrombosis accumulated TF mRNA at similar levels to LPS-treated normal MBC. Increased levels of TF mRNA were found in eight of ten patients with conventional aPL (ie, anti-cardiolipin antibodies [aCL] and/or lupus anticoagulant [LA]) and little if any accumulation of TF mRNA was observed in three of four patients without aPL at the time of study. These data strongly suggest that circulating monocytes of many patients with PAPS are subjected to an up-regulated TF expression that may well explain their prothrombotic state. Although the presence or absence of TF mRNA in MBC was associated with, respectively, the presence or absence of conventional aPL in 11 of the 14 patients studied, our study cannot exclude the involvement of factors other than aCL or LA in inducing TF expression.

Adult↗
PubMed1999

[Experimental vasectomy: comparison of epididymal structure with various surgical techniques].

OBJECTIVE: To analyze the effects of different surgical techniques of vasectomy on the epididymal structure. METHODS: Experimental vasectomies were performed in dogs using the conventional and open-ended techniques. The animals were orchidectomized 1 to 12 months after vasectomy and the epididymal structure was analyzed. RESULTS: The epididymal structure of dogs submitted to the conventional technique showed marked ectasia, reinforced basement membrane, loss of stereocilia in the principal cells, and formation of spermatic granulomas in interstitial tissue. At 12 months the principal cells showed signs of degenerative changes. In the different time periods analyzed in the study, no changes were observed in the epididymal structure of dogs submitted to the open-ended technique. CONCLUSIONS: The changes observed in the principal cells are ascribable to the increased intraluminal pressure produced by ligation of both ends of the vas deferens (conventional technique), since no changes were found in the epididymal structure of dogs submitted to the open-ended technique, at least in the different time periods analyzed in the study.

Animals↗
PubMed1999

[Giant-cell myocarditis simulating an apical myocardial infarct].

We present a case of a 57-year-old man with a giant-cell myocarditis that made its debut as a sustained ventricular polymorphic tachycardia interpreted in the context of old apical myocardium infarct, with a posterior evolution towards refractory heart failure, which finally needed urgent cardiac transplantation. We explain the characteristics of this unusual myocarditis, which has a poor prognosis, and also the results of the laboratory techniques that led to an equivocal diagnosis in this patient.

Diagnosis, Differential↗
PubMed1999

[Pneumonia caused by Haemophilus influenzae. Study in a series of 58 patients].

Haemophilus influenzae tends to form part of the usual respiratory flora in adults, especially if they have a chronic underlying disease or are smokers. Pneumonia due to H. influenzae is frequently involved in respiratory infections and its level of resistance to ampicillin has remained stable over the last five years. Most of the literature on the subject was published more than 10 years ago. In this study, we describe the clinical features and evolution of 58 adult patients admitted to hospital for pneumonia due to H. influenzae over a 2-year period, with this group accounting for 6.5% of all the patients admitted with pneumonia during this time period. The etiological diagnosis was made using a good quality sputum sample. Forty patients (69%) were male. The mean age (+/- SD) of the group was 67 (+/-16.8) years and all the patients had at least one underlying disease. The mean duration of the symptoms was 6.7 days. All patients presented an increase in the quantity or purulence of the sputum. On admittance, respiratory failure was present in 52 patients (90%). Gram-negative coccus-bacilli were observed in the direct sputum test and H. influenzae grew in the culture. In two cases, H. influenzae was recovered from the blood culture and in one from bronchial aspiration obtained through bronchoscopy. Another pathogen was identified in 28 patients (48%). In 21 it was another pyogenic bacteria (15 S. pneumoniae, 4 M. catharralis, 1 K. pneumoniae, 1 E. coli), an atypical microorganism in 5 (3 C. pneumoniae, 2 C. burnetii) and a respiratory virus in 2 (syncytial and influenza A). Atypical bacteria and respiratory virus were detected using serological techniques. The radiographic infiltrate was unilobar in 54 of the 58 patients and all showed an alveolar pattern. The empirical treatment included the administration of a third generation cephalosporin (or a fluoroquinolone in patients allergic to penicillin). The evolution was favorable in all the cases in which H. influenzae was the only pathogen or was accompanied by an atypical microorganism or a respiratory virus. Four patients with mixed bacterial pneumonia died (2 S. pneumoniae, 1 E. coli and 1 M. catharralis). The study indicates that pneumoniae due to H. influenzae affects a population with an underlying disease, preferably pulmonary, that it has a longer clinical period than that for pneumococcal pneumonia, that it is slightly bacteremic and, that, usually, it evolves benignly with a low mortality.

Adult↗
PubMed1999

[Pneumonia due to Haemophilus influenzae.Study in a series of 58 patients]

Haemophilus influenzae tends to form part of the usual respiratory flora in adults, especially if they have a chronic underlying disease or are smokers. Pneumonia due to H. influenzae is frequently involved in respiratory infections and its level of resistance to ampicillin has remained stable over the last five years. Most of the literature on the subject was published more than 10 years ago. In this study, we describe the clinical features and evolution of 58 adult patients admitted to hospital for pneumonia due to H. influenzae over a 2-year period, with this group accounting for 6.5% of all the patients admitted with pneumonia during this time period. The etiological diagnosis was made using a good quality sputum sample. Forty patients (69%) were male. The mean age (+/- SD) of the group was 67 (+/-16.8) years and all the patients had at least one underlying disease. The mean duration of the symptoms was 6.7 days. All patients presented an increase in the quantity or purulence of the sputum. On admittance, respiratory failure was present in 52 patients (90%). Gram-negative coccus-bacilli were observed in the direct sputum test and H. influenzae grew in the culture. In two cases, H. influenzae was recovered from the blood culture and in one from bronchial aspiration obtained through bronchoscopy. Another pathogen was identified in 28 patients (48%). In 21 it was another pyogenic bacteria (15 S. pneumoniae, 4 M. catharralis, 1 K. pneumoniae, 1 E. coli), an atypical microorganism in 5 (3 C. pneumoniae, 2 C. burnetii) and a respiratory virus in 2 (syncytial and influenza A). Atypical bacteria and respiratory virus were detected using serological techniques. The radiographic infiltrate was unilobar in 54 of the 58 patients and all showed an alveolar pattern. The empirical treatment included the administration of a third generation cephalosporin (or a fluoroquinolone in patients allergic to penicillin). The evolution was favorable in all the cases in which H. influenzae was the only pathogen or was accompanied by an atypical microorganism or a respiratory virus. Four patients with mixed bacterial pneumonia died (2 S. pneumoniae, 1 E. coli and 1 M. catharralis). The study indicates that pneumoniae due to H. influenzae affects a population with an underlying disease, preferably pulmonary, that it has a longer clinical period than that for pneumococcal pneumonia, that it is slightly bacteremic and, that, usually, it evolves benignly with a low mortality.

Journal Article↗
PubMed1999

[Effects of 17 alpha-hydroxy-progesterone on cortico-caudate transmission in rats].

Estrogen and progesterone have known effects on the endocrine control of sexual functions, however there is renewed interest on their potential action on extrahypothalamic sites. Previous results obtained in this laboratory, showed that estradiol has an inhibitory effect on cortico-caudate transmission. In this study the action of 17 alpha-Hydroxy-Progesterone on cortico-caudate transmission was assessed. Intact, ovariectomized female rats and intact male Sprague-Dawley rats were anesthetized with chloral hydrate (40 mg/100 g i.p.) and 17 alpha-Hydroxy-Progesterone (10 microliters of a 2.5 mg/ml solution) was administered via a right jugular catheter. Conventional electrophysiological recordings were made in the caudate nucleus by means of glass electrodes, and the motor cortex was electrically stimulated by means of metal electrodes, insulated except at the tip. Excitatory responses were analyzed by a computer, adding successive sweeps to build Post-stimulus time histograms. Injection of 17 alpha-Hydroxy-Progesterone produced an increase in the magnitude of the response in the majority of neurons tested (95%). In some cells this increase was followed by a decrease (35%), and in one case the excitatory response was decreased. These changes started 5 to 10 minutes after the injection, and lasted for about one hour, when the excitatory response returned to control values. These results show that progesterone can modulate cortico-caudate transmission in the rat, and suggest that due to the short latency of this effect, this could be exerted through a non-genomic mechanism of action.

17-alpha-Hydroxyprogesterone↗
PubMed1998

[Clinical factors that affect the detection of BCR-ABL transcripts after allogenic bone marrow transplantation for chronic myeloid leukemia].

BACKGROUND: To evaluate the relationship between clinical parameters and the ability to detect BCR-ABL-positive cells in a series of 27 long survivor patients after allogeneic bone marrow transplantation (BMT) for chronic myelogenous leukemia (CML). PATIENTS AND METHODS: A total of 78 samples obtained between 1 and 160 months after BMT were analyzed for the presence of the BCR-ABL transcript detected by the reverse-transcription polymerase chain reaction (PCR) using nested primers. Median follow up was 83 months. RESULTS: 16 patients were persistently PCR-positive and 7 patients persistently PCR-negative. The original transcript became negative in four patients. Only two of the positive cases developed hematologic relapse during the period of study. High white blood cell counts before BMT (17.88 vs 10.12 x 10(9)/l; p = 0.008) and immunosuppressive therapy for chronic graft-versus-host disease (p < 0.05) were associated with an increased ability to detect residual BCR-ABL positive cells. CONCLUSIONS: Our data show that most patient are persistently BCR-ABL positive after BMT for CML. If these findings represents a dynamic balance between the tumour burden prior BMT and the immunological capability of the graft must be confirmed in further studies.

Adolescent↗
PubMed1998

[Surgical management of soft tissue sarcomas: principles of resection and reconstructive plastic procedures].

1. Adequate complete surgical resection with a oncologic radical or wide margin of normal tissue represents the most important measure to prevent a local recurrence. Limited excision with "shelling-out" of the tumor, through its "pseudocapsule" almost invariably means positive microscopic margins. The pathohistologically or macroscopically marginal or intralesional positive resection margins make a salvage surgery necessary. 2. A close safety margin of < 1 cm due to neighboured anatomic structures indicates a high risk of local recurrence and makes an adjuvant radiotherapy mandatory. Plastic-reconstructive surgery should prepare the radiotherapy fields, to avoid cavities or ulcerations. 3. Facts should be stated in the clinical record and the operation report, e.g. the safety margin should be defined by the surgeon and the pathologist; the histopathologic stage and grade are absolutely basic requirements. If necessary, a second histopathologic review should be asked for. 4. Tumor resection and reconstructive oncoplastic measures should correspond individually to the oncologic parameters, to the functional demands and to the age of the patient. 5. Multidisciplinary cooperation in a tumorboard is a precondition for an adequate treatment.

Humans↗
PubMed1998

Mutational spectra of a 100-base pair mitochondrial DNA target sequence in bronchial epithelial cells: a comparison of smoking and nonsmoking twins.

Seventeen separate mitochondrial hot spot mutations in a 100-bp target sequence (mitochondrial bp 10,030-10,130) were detected and measured in bronchial epithelial cell samples isolated from smokers and nonsmokers. Among the individuals sampled were three pairs of monozygotic twins in which one twin had never smoked and had a nonsmoking spouse, and the other had a smoking history of >10 pack-years. Individual point mutations present at frequencies as low as 10(-6) were detected. Partially denaturing electrophoresis was used to separate mutant from nonmutant sequences on the basis of their melting temperatures, and the target sequence was subsequently amplified via high-fidelity PCR with Pfu DNA polymerase. Tests were performed to determine whether mismatch intermediates or DNA adducts present in the cellular DNA were converted to mutants during PCR. Hot spot mutations were clearly observed in bronchial epithelial cells, and the same hot spots were observed consistently in different samples. Significant numerical variability in the mutant fractions for individual mutants was observed among samples and are ascribed to unequal mitochondrial segregation in stem and transition cells. The mutational spectra in smokers' samples did not differ significantly from the mutational spectra in nonsmokers' samples for this 100 bp of mitochondrial DNA. No smoking-specific hot spots were detected. The overall mutant fractions in smokers' samples were not elevated compared to those of nonsmokers. As much variability was observed between two samples from the same individual's lung as between a sample from a smoker and a sample from a nonsmoker. These findings demonstrate that inhaled tobacco smoke does not induce prominent point mutations in this 100-bp target mitochondrial sequence in smokers' bronchial epithelial cells. Endogenous factors (e.g., DNA replication errors or DNA damage by endogenous reactive chemicals) are suggested to be more likely to represent the most important contributors to mitochondrial mutagenesis.

Adult↗