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Biomedical subjects

A Alvarez

Publications and source records attributed to A Alvarez.

At least 37 records · Page 2Linked to original sources

HIV-1 subtypes in Spain: a retrospective analysis from 1995 to 2003.

OBJECTIVE: To perform a retrospective analysis of all HIV-1 non-B variants circulating in Spain from 1995 to 2003 and extend their virological characterization. METHODS: Samples from a total of 396 HIV-infected subjects with epidemiological suspicion of being infected with non-B clades were analysed during the study period. Subtyping was carried out on the protease (PR), reverse transcriptase (RT) and envelope (env) genes. RESULTS: PR sequences belonging to non-B subtypes were recognized in 43.2% of cases (23 A, 13C, 6D, 3F, 118 G, 3H, 4 J and 1 U). Subtype G and AG recombinants were the most frequent variants (69%), and were found most often in subjects from West and Central Africa. Up to 70% of pol (PR, RT) sequences belonging to subtype G harboured env sequences belonging to clade A (55%), B (13.8%) or K (3.4%). Nearly half were mosaic GA viruses, and a few were CRF 14 BG viruses. Up to 14 new recombinant viruses, which could not be assigned to previously described circulating recombinant forms (CRFs), were found. CONCLUSIONS: There is great diversity in the HIV-1 variants and recombinant viruses circulating in Spain. Non-B sequences may be underestimated if only the env region is examined in phylogenetic analyses. Drug resistance testing provides the advantage of pol subtyping, and its additional use for this purpose should be encouraged.

CD4 Lymphocyte Count↗

Antimicrobial therapy for pulmonary pathogenic colonisation and infection by Pseudomonas aeruginosa in cystic fibrosis patients.

Pseudomonas aeruginosa colonisation has a negative effect on pulmonary function in cystic fibrosis patients. The organism can only be eradicated in the early stage of colonisation, while reduction of bacterial density is desirable during chronic colonisation or exacerbations. Monthly, or at least 3-monthly, microbiological culture is advisable for patients without previous evidence of P. aeruginosa colonisation. Cultures should be performed at least every 2-3 months in patients with well-established colonisation, and always during exacerbations or hospitalisations. Treatment of patients following the first isolation of P. aeruginosa, but with no clinical signs of colonisation, should be with oral ciprofloxacin (15-20 mg/kg twice-daily for 3-4 weeks) plus inhaled tobramycin or colistin (intravenous treatment with or without inhaled treatment can be used as an alternative), while patients with acute infection should be treated for 14-21 days with high doses of two intravenous antimicrobial agents, with or without an inhaled treatment during or at the end of the intravenous treatment. Maintenance treatment after development of chronic P. aeruginosa infection/colonisation (pathogenic colonisation) in stable patients (aged>6 years) should be with inhaled tobramycin (300 mg twice-daily) in 28-day cycles (on-off) or, as an alternative, colistin (1-3 million units twice-daily). Colistin is also a possible choice for patients aged<6 years. Treatment can be completed with oral ciprofloxacin (3-4 weeks every 3-4 months) for patients with mild pulmonary symptoms, or intravenously (every 3-4 months) for those with severe symptoms or isolates with ciprofloxacin resistance. Moderate and serious exacerbations can be treated with intravenous ceftazidime (50-70 mg/kg three-times-daily) or cefepime (50 mg/kg three-times-daily) plus tobramycin (5-10 mg/kg every 24 h) or amikacin (20-30 mg/kg every 24 h) for 2-3 weeks. Oral ciprofloxacin is recommended for patients with mild pulmonary disease. If multiresistant P. aeruginosa is isolated, antimicrobial agents that retain activity are recommended and epidemiological control measures should be established.

Amikacin↗

Genotype-phenotype correlation for pulmonary function in cystic fibrosis.

BACKGROUND: Since the CFTR gene was cloned, more than 1000 mutations have been identified. To date, a clear relationship has not been established between genotype and the progression of lung damage. A study was undertaken of the relationship between genotype, progression of lung disease, and survival in adult patients with cystic fibrosis (CF). METHODS: A prospective cohort of adult patients with CF and two CFTR mutations followed up in an adult cystic fibrosis unit was analysed. Patients were classified according to functional effects of classes of CFTR mutations and were grouped based on the CFTR molecular position on the epithelial cell surface (I-II/I-II, I-II/III-V). Spirometric values, progression of lung disease, probability of survival, and clinical characteristics were analysed between groups. RESULTS: Seventy four patients were included in the study. Patients with genotype I-II/I-II had significantly lower current spirometric values (p < 0.001), greater loss of pulmonary function (p < 0.04), a higher proportion of end-stage lung disease (p < 0.001), a higher risk of suffering from moderate to severe lung disease (odds ratio 7.12 (95% CI 1.3 to 40.5)) and a lower probability of survival than patients with genotype I-II/III, I-II/IV and I-II/V (p < 0.001). CONCLUSIONS: The presence of class I or II mutations on both chromosomes is associated with worse respiratory disease and a lower probability of survival.

Adult↗

Significance of cytosolic hyaluronan levels in gastric cancer.

BACKGROUND: Hyaluronan a high-molecular weight glycosaminoglycan, is considered to be involved in the growth and progression of malignant tumours. The objective of this work was to evaluate the cytosolic hyaluronan content in gastric cancer cells, its possible relationship with clinicopathological tumour parameters and its potential prognostic significance. METHODS: Cytosolic hyaluronan levels were examined utilizing immunoenzymatic techniques in 129 patients with gastric cancer. The mean follow-up period for these patients was 28 months. RESULTS: Cytosolic hyaluronan levels ranged widely in tumours as well as in adjacent mucosal samples (median (range) 2822 (50-24,523) versus 3650 (507-20,782) ng/mg protein). Statistical analysis showed that tumour hyaluronan levels correlated significantly with patient's sex and the presence of lymphatic invasion. In addition, high tumour hyaluronan levels were significantly associated with shorter overall survival period (p<0.05). CONCLUSIONS: Our results suggest that high tumoral cytosolic hyaluronan levels are associated with lesions of unfavorable outcome in gastric cancer patients. Thus, hyaluronan may provide additional prognostic information to that given by other biochemical markers currently used in gastric cancer.

Adenocarcinoma↗

Antibacterial activity of essential oils of Pimenta racemosa var. terebinthina and Pimenta racemosa var. grisea.

The antibacterial activity of essential oils of Pimenta racemosa var. terebinthina and P. racemosa var. grisea was determined against Gram (+) and Gram (-) bacteria. P. racemosa var. grisea demonstrated a more pronounced activity. These data would indicate the potential usefulness of the variety grisea as a microbiostatic, antiseptic or disinfectant agent.

Anti-Bacterial Agents↗

Antinociceptive and anti-inflammatory effect of the aqueous extract from leaves of Pimenta racemosa var. ozua (Mirtaceae).

The leaves of Pimenta racemosa var. ozua (Urban & Ekman) Landrum L. (Myrtaceae) are used against the pain and the inflammation in popular medicine of the Caribe area. In the present work, the antinociceptive, anti-inflammatory effect, and acute toxicity of the aqueous extract from leaves of Pimenta racemosa have been investigated. The antinociceptive action was assayed in several experimental models in mice: acetic acid, formalin, and hot plate tests. The aqueous extract (125 and 250 mg/kg) significantly and in a dose-dependent manner reduced the nociception induced by the acetic acid intraperitoneal injection (P<0.001). In the formalin test, the extract also significantly reduced the painful stimulus in both phases of the test (P<0.001). On the contrary, the extract neither significantly increased the latency time of licking nor jumping in the hot plate test. In the anti-inflammatory study, the plant also showed an interesting effect. Aqueous extract (125 and 250 mg/kg) orally administered, significantly reduced the carrageenan-induced edema in rat paw at 1, 3, and 5 h (P<0.001). In the TPA test the edema was dose-dependent and significantly reduced by the extract (0.5, 1, and 3 mg per ear) when it was topically applied (P<0.01; P<0.001). The levels of myeloperoxidase enzyme also were reduced in the inflamed tissue by the extract. Acute toxicity also was investigated and the results indicated a moderate toxicity (LD50: 287 +/- 12.9 mg residue/kg; 1.854 +/- 0.083 g plant/kg). These results revealed that the extract from leaves of Pimenta racemosa var. ozua exerts an important antinociceptive activity, associated to an anti-inflammatory effect which to appear be markedly influenced by the inhibition of neutrophil migration into inflamed tissue and that lack of toxic effects at usual doses.

Analgesics↗

Neoplasia in solid organ transplant recipients: single-center experience.

The incidence of neoplasms among transplanted patients is increasing, being estimated at between 4% and 18% (mean = 6%). In this article we review the neoplasms in 2514 patients who underwent transplantation in our hospital between 1981 and 2002 including 1579 kidneys, 418 hearts, 430 livers, 70 lungs, and 17 pancreas. We observed 170 tumors in 117 patients. The most frequent neoplasm was skin and lip carcinoma (30 patients) followed by PTLD (18 patients). Our results concur with the literature with one exception, a low incidence of PTLD in heart transplants, which may only be explained due to the use of preventive therapy with antiretroviral drugs.

Aged↗

[Pancoast syndrome and endobronchial tumor infiltration as the first manifestation of Hodgkin lymphoma].

The most common cause of Pancoast syndrome is bronchogenic carcinoma. Other less common causes are solid tumor metastases, other chest tumors, infections, and hematologic neoplasms. Pancoast syndrome due to lymphoma is very rare, and cases described in the literature are essentially associated with non-Hodgkin lymphomas. In a review of the literature we found a single case of Pancoast syndrome secondary to a Hodgkin lymphoma; however, the syndrome manifested during recurrence of disease in that patient. We report a case of nodular sclerosis Hodgkin lymphoma which first manifested clinically as Pancoast syndrome and which was initially diagnosed by bronchial biopsy.

Bronchial Neoplasms↗

Evaluation of the European Union Maize Landrace Core Collection for resistance to Sesamia nonagrioides (Lepidoptera: Noctuidae) and Ostrinia nubilalis (Lepidoptera: Crambidae).

Two corn borer species are the principal maize insect pests in Europe, the European corn borer, Ostrinia nubilalis (Hübner), and the pink stem borer, Sesamia nonagrioides (Lefebvre). Hence, it would be advisable to evaluate the European maize germplasm for corn borer resistance to generate European varieties resistant to corn borer attack. The creation of the European Union Maize Landrace Core Collection (EUMLCC) allowed the screening of most of the variability for European corn borer resistance present among European maize local populations from France, Germany, Greece, Italy, Portugal, and Spain, testing a representative sample. The objective of this study was the evaluation of stem and ear resistance of the EUMLCC to European corn borer and pink stem borer attack. Trials were made at two Spanish locations that represent two very different maize-growing areas. Populations that performed relatively well under corn borer infestation for stem and ear damage were 'PRT0010008' and'GRC0010085', among very early landraces; 'PRT00100120' and 'PRT00100186', among early landraces; 'GRC0010174', among midseason landraces; and 'ESP0070441', among late landraces. Either the selection that could have happen under high insect pressure or the singular origin of determined maize populations would be possible explanations for the higher corn borer resistance of some landraces. Landraces 'PRT0010008', 'FRA0410090', 'PRT00100186', and 'ESP0090214' would be selected to constitute a composite population resistant to corn borers and adapted to short season, whereas populations 'ESP0090033', 'PRT00100530', 'GRC0010174', and 'ITA0370005' would be used to make a resistant composite adapted to longer season.

Animals↗

Cells from the inner mass of blastocyst as a source of neural derivates for differentiation studies.

Our results show that cells derived from the inner cell mass (ICM) show a clear tendency to differentiate into the neural lineage, showing both cells and structures in different degrees of differentiation. Among the experimental paradigms used to learn about neural differentiation, there have been several lines of investigation on stem cells, including embryonic stem (ES) cells isolated from the inner cell mass of embryo and also stem cells derived from embryonic carcinoma (EC). In this work, we have used a cellular line obtained from the inner cell mass of a blastocyst. The cells were cultured and after inoculated subcutaneously in syngenic mice. The neural differentiation was predominant, and could be observed both by morphological and immunohistochemical methods. It was represented by neural-tubes, neurons and glial cells, as expressed by the presence of Microtubule-associated protein-2 (MAP-2) and glial fibrilary acidic protein. Moreover, tyrosine hydroxilase positive labelling was found in neuron-like cells, which suggest the chatecolaminergic differentiation. These results show that isolation of cells from the inner mass of blastocyst represents an easy, reproducible and cheap source of neural derivates suitable for both in vivo and in vitro differentiation studies.

Animals↗

Lung transplants with tacrolimus and mycophenolate mofetil: a review.

Traditionally, immunosuppressive maintenance therapy in solid organ transplantation has consisted of cyclosporine (CsA), azathioprine, and prednisone. However, lung transplant recipients are far more frequently affected by acute rejection, especially during the first 6 months after the transplantation, than patients with other transplanted organs. Further, they display a greater risk for chronic transplant dysfunction and ultimate graft loss. Bronchiolitis obliterans syndrome (BOS) is the major cause of morbidity and mortality among long-term survivors after lung transplantation. Acute pulmonary allograft rejection has been identified as the major risk factor for the development of BOS. Based on favourable results in kidney, liver, and heart transplantation, tacrolimus and mycophenolate mofetil have been used as primary prophylaxis and as rescue therapy for recurrent or persistent acute rejection and BOS. A secondary indication is CsA toxicity. This review focuses on reported results of the combination of tacrolimus and mycophenolate mofetil in lung transplantation. These new immunosuppressive drugs have markedly improved the efficacy profiles without additional detrimental toxicities, and appear to be a safe alternative to CsA and azathioprine in patients following lung transplantation. However, at present, BOS is not influenced by these new drugs. The optimal long-term immunosuppressive regimen remains to be established.

Clinical Trials as Topic↗

Cardiovascular risk profile in nondiabetic renal transplant patients: cyclosporine versus tacrolimus.

Calcineurin inhibitors (CIs) contribute to cardiovascular risk (CR) in renal transplant (RT) patients. However, the CR profile in RT patients without preexistent diabetes is not well known. We compared CR factors in 191 nondiabetic RT recipients with functioning grafts beyond 1 year, receivingly either CsA (Neoral; n=100) or tacrolimus (Tac; n= 91). Clinical data and pretransplant CR profiles were similar in both groups. There were no differences in acute rejection episodes and graft survival rates during follow-up. The overall proportions of posttransplant diabetes (9% versus 6%), and of hypertension (73% vs 63%) were similar in both groups. Hyperlipidemia was more frequent in the CsA group (58% vs 31%; P=.0001). The cholesterol levels in the CsA group showed at 3 months (232+/-47 vs 202+/-42 m/dL; P=.0001), 6 months (232+/-49 vs 205+/-41 mg/dL; P=.0001), and 12 months (217+/-50 vs 202+/-40 mg/dL; P=.028), despite receiving a greater proportion of lipid-lowering drugs (49% vs 15%; P=.0001). Logistic regression analysis showed that CsA was an independent predictor of posttransplant hyperlipidemia (OR: 5.8, CI 95%; 3.3-10.7; P=.0001) as were age, female gender, pretransplant dyslipidemia, and body mass index (BMI). Interestingly, an interaction was observed between pretransplant BMI and CIs: Among pretransplant normal weight patients (BMI <25 kg/m2), CsA produced a greater incidence of hyperlipidemia than tacrolimus (58% vs 23%; P=.0001) while not among patients who were overweight (BMI >25 kg/m2: pretransplant 58% vs 42%; P=.341). In conclusion, CsA confers a higher risk of hyperlipidemia after RT in nondiabetic patients, particularly those with normal pretransplant weight.

Adult↗

[Gastrointestinal bleeding after endoscopic treatment of polypoid hamartoma (adenoma of Brunner's glands)].

The incidence of polypoidal tumors in the duodenum is scarce and Brunner's gland tumors represent 11% of these proliferations. Brunner's gland polypoid hamartoma or adenoma is a highly infrequent benign polypoid proliferation of Brunner's glands that is usually asymptomatic, although gastrointestinal bleeding or intestinal obstruction may sometimes occur. We present the case of a woman with an incidental diagnosis of duodenal polypoid hamartoma. The lesion was resected with polypectomy loop and at 48 h, the patient presented gastrointestinal bleeding as a complication. We describe the endoscopic treatment of the lesion and this complication.

Adult↗