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L Alonso

Publications and source records attributed to L Alonso.

At least 55 records · Page 3Linked to original sources
PubMed1995

In vivo gene transfer into murine corneal endothelial and trabecular meshwork cells.

PURPOSE: To determine whether a reporter gene can be introduced into adult mammalian corneal endothelial and trabecular meshwork cells in vivo using a recombinant replication-deficient adenovirus. METHODS: Purified replication-deficient adenovirus containing the cytomegalovirus-promoted Escherichia coli reporter gene, lacZ, was injected into the vitreous cavities or anterior chambers of 30 adult CD-1 mice using the contralateral eyes as controls. LacZ expression was assessed histochemically in enucleated eyes from 2 to 21 days after injection using the beta-Galactosidase (beta-Gal) assay. RESULTS: LacZ expression was demonstrated in corneal endothelial and trabecular meshwork cells for as long as 14 days after injection. beta-Gal activity was also observed in lens and iris epithelial cells. There was no toxicity of the adenoviral vector demonstrated histologically, and no nonocular tissues expressed lacZ as measured by beta-Gal assay. CONCLUSIONS: A functional gene can be transferred in vivo into adult mammalian corneal endothelial and trabecular meshwork cells using a replication-defective adenoviral vector. Gene expression is relatively short-lived compared to that demonstrated previously in other ocular tissues (photoreceptors and retinal pigment epithelium). Adenoviral vectors may be a viable means for short-term delivery of therapeutic genes in vivo to cells in the anterior segment of the eye.

Adenoviruses, Human↗
PubMed1995

[Coronary angioscopy: initial experience during coronary interventions].

BACKGROUND AND OBJECTIVE: Percutaneous coronary angioscopy (CAG) provides in vivo visual information about the luminal aspect of the vessel. In this report we describe our initial experience with CAG during coronary angioplasty (PTCA). METHODS: Fifty-five patients (age 60 +/- 9 years), 8 female, were included. Most patients, 42 (76%) were treated for unstable angina. RESULTS: In 49 patients (89%) CAG was performed prior to PTCA, and in all cases the intraluminal material responsible of the stenosis was recognized. This included plaque associated to thrombus in 29 patients (59%), isolated plaque in 15 (31%) and isolated thrombus in 5 (10%). Of these plaques, 25 (57%) were yellow, 14 (32%) were yellow and white and 5 (11%) were white. Of the 34 thrombi, 23 (68%) were mural and 11 (32%) protruding. CAG post-PTCA was performed in 43 patients (78%). CAG visualized residual plaque in 41 patients (95%) and residual thrombus in 34 (79%). In addition, CAG recognized dissections in 30 patients (70%). CAG was more sensitive than angiography for the detection of thrombus (pre-PTCA 34 [69%] vs 11 [22%]; p < 0.05, and post-PTCA 34 [79%] vs 5 [12%]; p < 0.05]) and coronary dissections (post-PTCA 30 [70%] vs 19 [44%]; p < 0.05). CAG before intervention caused angina in 39 patients (80%), ventricular fibrillation (successfully managed with DC cardioversion) in 1, and AV block in another patient. The angiographic result deteriorated in 4 patients (9%) immediately after the CAG performed following PTCA. A repeat balloon PTCA was required in these patients. CONCLUSIONS: CAG provides unique information on coronary lumen surface that complements angiographic data. As compared with angiography, CAG is more sensitive in the detection of intracoronary thrombi and dissections. Further studies are required to determine whether the additional information provided by CAG may be used, to select coronary interventions according to specific lesion characteristics, to optimize dilation results and, eventually, to improve the clinical outcome of these patients.

Aged↗
PubMed1995

[Cardiac tamponade with the absence of a paradoxical pulse. The practical utility of echocardiography].

A patient with cardiac tamponade but without hypotension and pulsus paradoxus is reported. In this patient, echocardiography confirmed the diagnosis of cardiac tamponade, showing diastolic collapse of the right ventricle and also the presence of an atrial septal defect (ostium secundum) that explains the absence of pulsus paradoxus. The role of echocardiography in those rare clinical situations that in the presence of cardiac tamponade showed no pulsus paradoxus are discussed.

Cardiac Tamponade↗
PubMed1994

Ontogeny of rat thymic dendritic cells.

In the present study we have combined various in vivo and in vitro approaches to analyse the appearance and development throughout ontogeny and postnatal life of the dendritic cell (DC) populations of rat thymus. The in situ ultrastructural study demonstrated immature interdigitating cells (IDC)/DC in the thymus of 17-day-old embryonic rats, but thymic stromal cell cultures from 16-day-old fetal rats seemed to contain DC precursors which, after several days in culture, produced strongly class II major histocompatibility complex (MHC)-positive, mature DC. According to morphology and class II MHC expression we also defined three different DC populations in the late embryonic rat thymus; two of them, which remained in the adult rat thymus, could represent distinct developmental stages within the IDC/DC lineage. The third cell subset might be involved in a massive process of negative selection, presumably occurring at the end of fetal life in the rat thymus. In supporting the existence of thymic DC subpopulations, we also demonstrated a differential expression of various cell markers, including CD4, CD8, CD25, adhesion molecules and the antigen recognized by OX44 monoclonal antibody (mAb), on thymic DC during both embryonic and adult life. Their possible significance for the attributed functions to thymic DC are discussed extensively.

Animals↗
PubMed1994

Morphometrical changes in the rat thymic lymphoid cells after treatment with two different doses of estradiol benzoate.

In the present study we have evaluated morphometrically the contribution of thymocytes to the thymic involution induced by a single injection either of 100 micrograms or 500 micrograms of estradiol benzoate. Our results demonstrate that changes in the numbers of both cortical and medullary thymocytes contribute to thymic involution although the importance of the first is quantitatively higher. On the other hand, while cortical pyknosis and a decreased mitotic index could be important for explaining the estrogen-dependent thymic changes, the release of lymphocytes from thymus seems to be the main factor inducing the thymic involution as well as the lack of recovery observed at the end of the experimental period.

Animals↗
PubMed1994

The diffusely-infiltrated lymphoid tissue of the bursa of Fabricius of Sturnus unicolor. Histological organization and functional significance.

In the present study we confirm and extend previous reports about the existence of a T-dependent area in the bursa of Fabricius of some birds, analyzing ultrastructurally the cell content of the so-called diffusely-infiltrated lymphoid tissue of the bursa of the spotless starling, Sturnus unicolor. It consists of lymphocytes, plasma cells, macrophages (Mphis) and interdigitating cells (IDCs) in a supporting reticular stroma which, apart from blood capillaries, contains postcapillary high-endothelial venules (HEVs). The presence of both IDCs and HEVs confirms the T-cell-dependent nature of this area, as previously claimed for other avian species, and emphasizes other functions, apart from its role in B-cell maturation, for the bursa of Fabricius specially in adult birds.

Aging↗
PubMed1993

In vitro antigen trapping by gill cells of the rainbow trout: an immunohistochemical study.

An in vitro assay was used to study the involvement of gill cells in the trapping and processing of particulate antigens. Gills were routinely processed for light microscopy after being placed in medium containing either Yersinia ruckeri O-antigen-labelled fluorescent beads, unlabelled fluorescent beads, Y, ruckeri O-antigen or formalin-killed Y. ruckeri, for 0, 30 s, 1, 5 and 30 min. Y. ruckeri formalin-killed cells, Y. ruckeri O-antigen and fluorescent beads labelled with Y. ruckeri O-antigen were taken in by gill epithelial cells as soon as 30 s after administration. In contrast, unlabelled fluorescent beads adhered to the epithelial cell membranes, but did not occur inside the gill cells. These results are discussed principally in relationship with the specificity of antigen trapping.

Animals↗
PubMed1992

Weekly first-line chemotherapy of metastatic breast cancer with cyclophosphamide and epirubicin.

Forty-six patients with metastatic breast cancer who had not received previous chemotherapy for advanced disease entered a phase II trial of weekly chemotherapy with cyclophosphamide (250 mg/m2) + epirubicin (25 mg/m2) for 16 weeks. The overall response rate was 61% (95% confidence limits, 47-75%), with 10 complete and 17 partial responses. Toxicity was mild and confined to nausea and vomiting and asymptomatic neutropenia (except in 2 cases). Sixty-three per cent of patients had no side effects. Weekly cyclophosphamide + epirubicin is an active and nontoxic regimen for patients with metastatic breast cancer who have had no prior anthracycline-containing adjuvant chemotherapy.

Adult↗
PubMed1992

Proposed guidelines for diagnosis of chromosome mosaicism in amniocytes based on data derived from chromosome mosaicism and pseudomosaicism studies.

Currently, accepted protocol which has been developed at the Prenatal Diagnosis Laboratory of New York City (PDL) requires that when a chromosome abnormality is found in one or more cells in one flask, another 20-40 cells must be examined from one or two additional flasks. Chromosome mosaicism is diagnosed only when an identical abnormality is detected in cells from two or more flasks. In a recent PDL series of 12,000 cases studied according to this protocol, we diagnosed 801 cases (6.68 per cent) of single-cell pseudomosaicism (SCPM), 126 cases (1.05 per cent) of multiple-cell pseudomosaicism (MCPM), and 24 cases (0.2 per cent) of true mosaicism. Pseudomosaicism (PM) involving a structural abnormality was a frequent finding (2/3 of SCPM and 3/5 of MCPM), with an unbalanced structural abnormality in 55 per cent of SCPM and 24 per cent of MCPM. We also reviewed all true mosaic cases (a total of 50) diagnosed in the first 22,000 PDL cases. Of these 50 cases, 23 were sex chromosome mosaics and 27 had autosomal mosaicism; 48 cases had numerical abnormalities and two had structural abnormalities. Twenty-five cases of mosaicism were diagnosed in the first 20 cells from two flasks, i.e., without additional work-up, whereas the other 25 cases required extensive work-up to establish a diagnosis (12 needed additional cell counts from the initial two culture flasks; 13 required harvesting a third flask for cell analysis). Our data plus review of other available data led us to conclude that rigorous efforts to diagnose true mosaicism have little impact in many instances, and therefore are not cost-effective. On the basis of all available data, a work-up for potential mosaicism involving a sex chromosome aneuploidy or structural abnormality should have less priority than a work-up for a common viable autosomal trisomy. We recommend revised guidelines for dealing with (1) a numerical versus a structural abnormality and (2) an autosomal versus a sex chromosome numerical aneuploidy. Emphasis should be placed on autosomes known to be associated with phenotypic abnormalities. These new guidelines, which cover both flask and in situ methods, should result in more effective prenatal cytogenetic diagnosis and reduced patient anxiety.

Amniocentesis↗
PubMed1992

Alternating chemotherapy for small-cell lung cancer. A twelve-week schedule of six drugs.

We have treated sixty-two patients (21 with limited disease, 41 with extensive disease), on an outpatient-basis schedule of six drugs administered weekly for twelve weeks. Cyclophosphamide, 400 mg/m2, adriamycin, 20 mg/m2 and vincristine, 2 mg, full dose, were administered during weeks 1, 5 and 9; cisplatin, 50 mg/m2 and etoposide, 100 mg/m2 during weeks 2, 6 and 10; adriamycin and vincristine at the same doses during weeks 3, 7 and 11; methotrexate 30 mg/m2, during weeks 4, 8 and 12. After the first 28 patients vincristine was replaced by teniposide (VM-26) due to neurotoxicity. The overall response rate was 64.5% (complete remission 13 p., partial remission 27 p.). Toxicity grade 3-4, mainly nausea and vomiting or neutropenia, was recorded in 17 patients. Alopecia grade 1-2 was universal. One toxic death occurred from sepsis. The overall survival was 8 months (range 1-40), (95% CL: 53-77%); 8 months in limited disease (range 1-40), and 7 months in extensive disease (range 1-23). Time to treatment failure was 6 months (7 limited disease, 5 extensive disease). In conclusion, the results of this alternating schedule are poorer than those attained with standard, high-dose treatments, mainly in limited disease, but could be a less toxic option for patients with extensive disease.

Adult↗
PubMed1989

[Hodgkin's disease associated with infection by human immunodeficiency virus].

We present four patients with Hodgkin's disease and human immunodeficiency virus infection (HIV). Three patients were addicts to parenteral drugs. The disease was very advanced at the time of diagnosis, stage IVB in all cases. Histologic types were mixed cellularity in two cases, nodular sclerosis in one case and it was not typifiable in the remaining case. The disturbances of cell-mediated immunity that the patients presented were those of the acquired immunodeficiency syndrome (AIDS) as well as the infectious complications. Response to treatment was poor with a high incidence of bone marrow toxicity; three patients died during the first 3 months after the diagnosis (X = 7.3 months). We emphasize the necessity of considering different prognostic and therapeutic approaches for the HD in these patients in contrast with those of seronegative patients. We pose some questions suggested by the review of the literature and the data of this series.

Adult↗
PubMed1989

[Arterial hypertension in the Baix Ebre region (Tarragona)].

The results of a cross-sectional study for the evaluation of the prevalence of hypertension in the Baix Ebre region (Tarragona) are reported. 628 individuals from a randomly selected sample of 670 gave their consent to participate. The study was based on interview and examination at the patients home after getting an appointment by post. The prevalence of hypertension was 31.84 +/- 3.64%, and that of borderline hypertension 16.56 +/- 2.97%. Only 57% of hypertensives were previously known as such, and only 18.5% of these were being correctly treated. There was a significant association of hypertension with age (basically systolic blood pressure for women); also with alcohol intake, obesity and family history of hypertension or cardiovascular disease. There was no significant correlation with sex, residence in rural or urban areas, emigration, marital status, occupational status, social and professional level, education, or with the coexistence of hypertension in the spouse. The high prevalence of hypertension was a remarkable finding, consistent with its recognized importance as a first rate health problem.

Adult↗
PubMed1988

Changes in hepatic and serum gamma-glutamyltransferase activities following chronic ethanol intake in rats.

The effect of chronic ethanol consumption on serum and liver gamma-glutamyltransferase (GGT) activities was studied in male Wistar rats. Animals were fed for 1-9 weeks a liquid diet containing 36% of total energy as ethanol or isocaloric carbohydrates. Compared to control diet, chronic ethanol significantly and progressively increased serum activity from 3 weeks of treatment. Liver GGT activity was also enhanced although changes were not parallel to those found in serum. Chronic ethanol intake led to an enhancement of liver glutathione concentration with a 45% increase at 3 weeks of treatment and a decrease thereafter. It is suggested that the increased hepatic GGT activity is not the only determinant of the enhanced serum levels of the enzyme and that it is not related to the modifications of liver glutathione content induced by ethanol consumption.

Animals↗