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J Roca

Publications and source records attributed to J Roca.

At least 37 records · Page 2Linked to original sources
PubMed2004

Flow cytometry identification of X- and Y-chromosome-bearing goat spermatozoa.

Flow cytometric sorting technology was used to measure the difference in DNA content between X- and Y-chromosome-bearing spermatozoa in bucks. Spermatozoa were analysed by flow cytometry to characterize X- and Y-chromosome-bearing sperm populations and to quantify the DNA difference between them. Two symmetrical, overlapping and clearly separated peaks, corresponding to X- and Y-bearing spermatozoa, were detected. The difference in fluorescence intensity between the peaks was 4.4 +/- 0.03% without any significant inter- or intra-animal variations. Therefore, the identification and selection of high-purity samples of sperm populations for sex sorting is easier in bucks compared with other domestic species.

Animals↗
PubMed2004

A cardiological web as an adjunct to medical teaching: prospective analysis.

The aim of the study was to deliver and evaluate an educational web for medical students. A web of the complete cardiovascular course was prepared as an adjunct educational material for the classes. The use and utility of the web was assessed through a questionnaire (frequency of use, impact on in-class attendance and students' satisfaction). The number of visits, the time of the week and the hour when the web was used were registered. A total of 76 students returned the questionnaire. The web was available for 10 weeks and was visited 1062 times, especially at weekends. An increase in visits was noted prior to final examination. The web was accessed preferentially from the faculty or hospital computers. The quality of the web was assessed and rated a mean of 7.7 (score: 1-10); 93.4% students attended the class, but the web freed them from transcribing the contents; 88.2% of students evaluated the web as a useful or very useful adjunct to medical teaching. The Internet can be used to deliver learning in medical students and could be considered as added value to the pedagogic process and did not deter students from attending ordinary classes.

Cardiology↗
PubMed2004

Comparative effects of autologous and homologous seminal plasma on the viability of largely extended boar spermatozoa.

Sperm handling, associated to artificial reproduction technologies (ART) such as in vitro fertilization (IVF) or the use of flow cytometry for cell analysis or sorting imposes volumetric extension of the sperm suspension and decreases sperm viability, presumably because of the removal of seminal plasma (SP) components. This study evaluated whether a 10% v/v of autologous SP (retrieved from the same donor boar) or homologous SP (e.g. from any of the four fertile boars included, other than the one providing the spermatozoa) would differently affect the viability of boar spermatozoa subjected to large extension in a simple saline medium [phosphate-buffered saline and 0.1% ethylenediaminetetraacetic acid (EDTA), PBSm] to a concentration of 0.3 x 10(6) spermatozoa/ml and incubated for 2 h at 30 degrees C. Sperm viability was monitored as membrane integrity [using the fluorophore carboxyfluorescein diacetate (C-FDA) and propidium iodide (PI)], mitochondrial function (using the fluorophore R-123) and motility characteristics [using Computer Assisted Sperm Analysis (CASA)]. Substraction of the SP and extension followed by incubation in PBSm significantly (p < 0.05) decreased sperm viability, which could be restored by addition of autologous SP. Furthermore, exposure of the extended spermatozoa to homologous SP (from any other individual boar) significantly (p < 0.05) varied with the source of the sire; some boars exerting beneficial effects (even surpassing the effects of the autologous SP; p < 0.05) while at least one boar negatively (p < 0.05) influencing the viability of the incubated spermatozoa. It is concluded that SP should be present when incubating highly extended spermatozoa. As a result of the obvious differences among boars, it would be advantageous to examine the ability of SP to maintain sperm viability prior to the use of SP pools during sperm handling in vitro.

Animals↗
PubMed2004

Formoterol protects against platelet-activating factor-induced effects in asthma.

Platelet-activating factor (PAF) is an inflammatory mediator that provokes neutropaenia, bronchoconstriction and gas exchange defects due to exudation of bulk plasma within the airways. While the inhibitory effects of short-acting beta2-agonists on PAF-induced disturbances have been consistently shown, those of long-acting beta2-agonists are less convincing. To further explore the mechanisms involved in PAF challenge in asthma, 12 patients (forced expiratory volume in one second, 90 +/- 4% predicted) were investigated 2 h after inhaled formoterol (18 microg), in a double-blind, placebo-controlled, crossover design following PAF (18 microg) inhalation. Compared with the placebo, at 5 min, premedication with formoterol reduced PAF-induced cough and dyspnoea, and attenuated increased respiratory system resistance (by 67%) and arterial deoxygenation (by 50%). Likewise, ventilation-perfusion (V'A/Q') inequality improved, as reflected by the dispersion of pulmonary blood flow (by 63%) and an overall index of V'A/Q' heterogeneity (by 71%). In contrast, PAF-induced facial flushing, neutropaenia and subsequent rebound neutrophilia remained unchanged. The improvement in gas exchange abnormalities shown after platelet-activating factor in patients with asthma pretreated with formoterol at the recommended clinical dose may reflect, in addition to its class effects, an anti-exudative effect of formoterol in the airways.

Administration, Inhalation↗
PubMed2004

Hoechst 33342 stain and u.v. laser exposure do not induce genotoxic effects in flow-sorted boar spermatozoa.

Sex selection by flow cytometry/cell sorting involves the staining of spermatozoa with Hoechst 33342 in combination with the impact of a u.v. laser beam, two potentially mutagenic agents. A phenotypic and cytogenetic study of lymphocytes of piglets born after insemination with spermatozoa stained with Hoechst 33342 and from piglets obtained from stain-sorted spermatozoa was performed to evaluate the genotoxic effect of Hoechst 33342 staining and u.v. laser irradiation on the offspring. Lymphocytes from piglets born after insemination with unstained spermatozoa, but from the same ejaculate, were used as a control group. Peripheral blood lymphocytes from these piglets were cultured following a standard cell culture protocol. Cells were then collected by centrifugation, subjected to hypotonic solution and fixed and dropped onto slides. Sister chromatid exchanges (SCEs) and chromosome aberrations (CAs: including chromosome and chromatid breaks) per cell were scored in 50-s division metaphase spreads from each donor. Reproductive parameters and litter performance of all inseminations performed were also recorded in all groups. Data were analyzed by ANOVA. No significant increase (P > 0.05) of SCE and CA frequencies were observed in piglets born from stained spermatozoa or from stain-sorted spermatozoa with respect to controls (untreated sperm). The results indicated that no mutagenic effect on spermatozoa, expressed as increases in the incidence of abnormalities in the resulting offspring and also as increases in SCE and CA frequencies on lymphocytes from these individuals, was induced by the staining of boar spermatozoa with Hoechst 33342, nor by combination of staining with laser impact during flow cytometry.

Animals↗
PubMed2003

Influence of follicle size on the penetrability of immature pig oocytes for homologous in vitro penetration assay.

In order to improve the performance of homologous in vitro penetration (hIVP) assays using immature oocytes to assess the penetrating ability of boar sperm, the present study was designed to evaluate the influence of oocyte and follicle size on the penetrability of immature pig oocytes obtained from slaughterhouse ovaries. Nonatretic antral follicles were isolated, measured with a computerized image analysis system and grouped according to their diameter: Group 1 (0.40-0.99 mm), Group 2 (1.00-2.19 mm), Group 3 (2.20-2.79 mm), and Group 4 (2.80-6.50 mm). After sperm coincubation and before penetrability evaluation, the immature oocytes were classified into four size categories according to their diameter excluding zona pellucida: <105, 105-109, 110-114, and > or =115 microm. As regards follicle size, the highest viability and penetrability were obtained with oocytes from follicles >2.20 mm (P>0.05). Regarding oocyte size, significant differences (P<0.05) were observed for all parameters evaluated between oocytes with a diameter above or below 110 microm. However, our results revealed that such differences were due to follicle size rather than oocyte diameter, since oocytes with the same diameter but from different follicle size groups showed different penetration rates. With increasing follicle size, the percentage of penetrated oocytes increased (P<0.05). Finally, our results showed that the greater penetrability of immature oocytes from larger follicles is not due to variations in the thickness of the zona pellucida. There were no significant differences in zona pellucida thickness between oocytes from the four follicular size groups. In summary, these results indicate that follicle size directly affects the penetrability of immature pig oocytes used in hIVP.

Animals↗
PubMed2003

Antigenicity of a recombinant NS3 protein representative of ATPase/helicase domain from hepatitis C virus.

It has been shown that the Hepatitis C virus nonstructural NS3 protein possesses at least two enzymatic domains: a serine-protease domain and an adenosine triphosphatase (ATPase)/helicase domain. In this report, a truncated fragment of NS3 (26 kDa), representing main epitopes from the (ATPase)/helicase domain, has been expressed in Escherichia coli. The recombinant protein was purified by Ion Metal Affinity Chromatography (IMAC) with more than 90% purity. The recognition of B-cell linear epitopes in the NS3 protein was evaluated by immunoblot. The recombinant NS3 protein was reduced and carboxymethylated, and the recognition of either conformational and/or linear B-cell determinants was evaluated by ELISA. The inclusion of the recombinant NS3 protein in a third-generation diagnostic system UltraMicroELISA (UMELISA) allowed an increase in the sensitivity, due to the detection of a new variety of false-negative sera in blood donor test samples.

Adenosine Triphosphatases↗
PubMed2003

Sirolimus in heart transplantation: a single center initial experience.

Sirolimus (SRL) is a potent non-nephrotoxic immunosuppressant. In our unit, SRL was administered to 17 heart transplant (HT) recipients at 1770+/-1234 days' posttransplant surgery, for the following reasons: (1) calcineurin inhibitor (CI) withdrawal due to renal insufficiency (RI; n=6); (2) neurotoxicity (n=1) and pancytopenia (n=1); (3) vascular graft disease (VGD) treatment (n=5); (4) immunosuppression optimization due to lung cancer (n=2); (5) CI use was delayed due to postsurgery RI (n=2). The mean follow-up was 190+/-165 days. Mean SRL doses (mg)/concentrations (ng/mL) at 7 (n=17), 30 (n=14), and 180 (n=8) days were: 1.2+/-0.6/5.9+/-6; 1.6+/-0.8/4.8+/-3.1; and 1.7+/-1.0/5.2+/-3.7. Among group 1, CI patients were discontinued without favorable functional impact. Neurotoxicity and pancytopenia improved, but there were no major clinical events in the VGD group. One "bridge" to CI was successfully performed (postsurgery RI). Total leukocyte count fell while hemoglobin, platelet, and cholesterol profiles were not affected. Ten of 15 patients (67%) were discontinued from CI without rejection and with a dose reduction of mycophenolate mofetil. There were 8 episodes (47%) of SRL-related toxicity, leading to 4 discontinuations (23%); 8 patients (47%) have died during follow-up. This retrospective analysis of outcomes in the context of severe complicated patients suggests that more premature introduction SRL is preferable, particularly in a large patient cohort.

Heart Transplantation↗
PubMed2003

Acute myocardial infarction with cardiogenic shock: treatment with mechanical circulatory assistance and heart transplantation.

UNLABELLED: The mortality of cardiogenic shock (CS) after an acute myocardial infarction (AMI) still remains high. Thrombolysis, PTCA or CABG, when possible, can improve the results, but when all the treatments fail death is almost certain. OBJECTIVE: We investigate the use of the mechanical circulatory assistance (MCA) and heart transplantation (HT) to improve the adverse results in this irreversible situation. METHODS: Among 11 patients with irreversible CS after an AMI we used a MCA (Abiomed BVS-5000). After improvement and hemodynamic stabilization, we performed heart transplantation in 7 patients of mean age 52 years (35-60) including two women. The MCA was univentricular in 7 patients and biventricular in 4. Mean duration of the MCA was 5 days (1-12). RESULTS: Three patients died during the MCA: two due to cerebrovascular accidents and one multiorgan failure. Weaning was possible in one patient. Among Seven transplanted patients one died due to sepsis. Seven (64%) patients are long-term survivors. CONCLUSION: When all the treatments have failed for CS after an AMI, MCA may be used as a bridge to heart transplantation in a select group of patients where the procedure is not contraindicated. The long-term results of 64% survivors in our experience is satisfactory.

Adult↗
PubMed2003

A prospective study of the incidence of skin cancer and its risk factors in a Spanish Mediterranean population of kidney transplant recipients.

BACKGROUND: Skin cancer is the most common malignancy occurring in kidney transplant recipients (KTRs). OBJECTIVES: Our purpose was to investigate, prospectively, the cumulative incidence of cancerous and precancerous skin lesions as well as their risk factors in a close follow-up population of KTRs from a Mediterranean area of Spain. PATIENTS AND METHODS: One hundred and seventy-four consecutive KTRs were examined at the moment of transplant and then at 6-month intervals. The cumulative incidence of skin cancer was computed. To analyse the role of potential risk factors (age at transplantation, cause of renal failure, duration of pretransplant dialysis, type of immunosuppressive regimen, sun-reactive skin type and history of occupational sun exposure), the Cox regression method was used. RESULTS: After a median follow-up of 72 months (range, 12-140), 39 patients (25.3%) developed 142 tumours [84 basal cell carcinoma (BCC) and 58 squamous cell carcinoma (SCC)]. The BCC/SCC ratio was 1.4 : 1. The cumulative incidence for skin cancer was 13% after 3 years of graft survival, increasing to 27.5% at 6 years and 48% at 10 years. Only age at the time of transplantation and occupational sun exposure had statistical significance as risk factors (P < 0.001). CONCLUSIONS: Our study confirms the high incidence of non-melanoma skin cancer among KTRs in a Mediterranean population with occupational sun exposure and the patient's age at the time of transplantation being the main risk factors. We believe that all organ transplant programs should provide educational information about protecting oneself from the sun as well as include follow-up visits by dermatologists in order to facilitate early diagnosis and treatment of skin cancer.

Adolescent↗
PubMed2003

Unsupervised self-testing of airway obstruction by forced oscillation at the patient's home.

As active patient cooperation is not required, the forced oscillation technique (FOT) could be suitable for measuring airway obstruction in routine home applications. Nevertheless, FOT has never been used at the patient's home to date. The aim of this study was to assess the feasibility of FOT and the reproducibility of measured respiratory resistance (Rrs) in routine patient self-testing at home. Altogether, nine asthmatic patients self-measured their Rrs with a portable FOT device and spirometry for 10-14 days, in the morning and evening, and before and after bronchodilator inhalation. During each measurement session, the patients carried out four consecutive FOT measurements. Grubbs' discordancy test for detecting outliers was used to evaluate intermeasure reliability. Only 4.9% of Rrs data reported by patients were rejected as artefacts. The coefficient of variation of Rrs was 7.9 +/- 6.3% (mean +/- SD). When compared with spirometry, the per cent change in Rrs for detecting a positive bronchodilator response showed an 83% sensitivity and 72% specificity. Unsupervised self-measurement of respiratory resistance at the patient's home provided results similar to those obtained by a technician in a lung function lab. Forced oscillation technique could be a useful tool for the routine follow-up of asthmatic patients at home.

Adult↗
PubMed2003

Home hospitalisation of exacerbated chronic obstructive pulmonary disease patients.

It was postulated that home hospitalisation (HH) of selected chronic obstructive pulmonary disease (COPD) exacerbations admitted at the emergency room (ER) could facilitate a better outcome than conventional hospitalisation. To this end, 222 COPD patients (3.2% female; 71+/-10 yrs (mean+/-SD)) were randomly assigned to HH (n=121) or conventional care (n=101). During HH, integrated care was delivered by a specialised nurse with the patient's free-phone access to the nurse ensured for an 8-week follow-up period. Mortality (HH: 4.1%; controls: 6.9%) and hospital readmissions (HH: 0.24+/-0.57 controls: 0.38+/-0.70) were similar in both groups. However, at the end of the follow-up period, HH patients showed: 1) a lower rate of ER visits (0.13+/-0.43 versus 0.31+/-0.62); and 2) a noticeable improvement of quality of life (delta St George's Respiratory Questionnaire (SGRQ), -6.9 versus -2.4). Furthermore, a higher percentage of patients had a better knowledge of the disease (58% versus 27%), a better self-management of their condition (81% versus 48%), and the patient's satisfaction was greater. The average overall direct cost per HH patient was 62% of the costs of conventional care, essentially due to fewer days of inpatient hospitalisation (1.7+/-2.3 versus 4.2+/-4.1 days). A comprehensive home care intervention in selected chronic obstructive pulmonary disease exacerbations appears as cost effective. The home hospitalisation intervention generates better outcomes at lower costs than conventional care.

Aged↗
PubMed2003

Increased tumour necrosis factor-alpha plasma levels during moderate-intensity exercise in COPD patients.

Post-training downregulation of muscle tumour necrosis factor (TNF)-alpha messenger ribonucleic acid (mRNA) expression and decrease in cellular TNF-alpha levels have been reported in the elderly. It is hypothesised that chronic obstructive pulmonary disease (COPD) patients may not show these adaptations due to their reduced ability to increase muscle antioxidant capacity with training. Eleven COPD patients (forced expiratory volume in one second 40 +/- 4.4% of the predicted value) and six age-matched controls were studied. Pre- and post-training levels of TNF-alpha, soluble TNF receptors (sTNFRs: sTNFR55 and sTNFR75) and interleukin (IL)-6 in plasma at rest and during exercise and vastus lateralis TNF-alpha mRNA were examined. Moderate-intensity constant-work-rate exercise (11 min at 40% of pretraining peak work-rate) increased pretraining plasma TNF-alpha levels in COPD patients (from 17 +/- 3.2 to 23 +/- 2.7 pg x mL(-1); p<0.005) but not in controls (from 19 +/- 4.6 to 19 +/- 3.2 pg x mL(-1)). No changes were observed in sTNFRs or IL-6 levels. After 8 weeks' endurance training, moderate-intensity exercise increased plasma TNF-alpha levels similarly to pretraining (from 16 +/- 3 to 21 +/- 4 pg x mL(-1); p<0.01). Pretraining muscle TNF-alpha mRNA expression was significantly higher in COPD patients than in controls (29.3 +/- 13.9 versus 5.0 +/- 1.5 TNF-alpha/18S ribonucleic acid, respectively), but no changes were observed after exercise or training. It is concluded that moderate-intensity exercise abnormally increases plasma tumour necrosis factor-alpha levels in chronic obstructive pulmonary disease patients without exercise-induced upregulation of the tumour necrosis factor-alpha gene in skeletal muscle.

Aged↗
PubMed2003

Fluorescence in situ hybridization in diluted and flow cytometrically sorted boar spermatozoa using specific DNA direct probes labelled by nick translation.

Successful evaluation of X- and Y-chromosome-bearing sperm separation technology using flow cytometry-cell sorter is of great importance. Fluorescence in situ hybridization (FISH), which allows for the detection of specific nucleic acid sequences on morphologically preserved spermatozoa, is an ideal method for quantitatively and qualitatively assessing the purity of sorted sperm samples. In this study specific pig DNA direct probes for small regions of chromosomes 1 and Y were used. Chromosome 1 was labelled in green and used as internal control to detect a lack of hybridization, whereas chromosome Y was labelled in red. Nick translation was used as the labelling method for the preparation of these probes. Spermatozoa, unsorted and sorted for high and low Y-chromosome purity from ejaculates of five boars, were fixed on slides and two-colour direct FISH was performed for chromosomes 1 and Y. About 500 non-sorted and 200 sorted spermatozoa per sample were scored. The proportion of Y-chromosome-bearing spermatozoa was determined by the presence of a red fluorescent signal on the sperm head and the proportion of X-chromosome-bearing spermatozoa was determined by subtraction. The efficiency of the hybridization procedure was established as near 98% on sorted and unsorted samples. The results of this study confirm that direct FISH using specific pig DNA probes labelled by nick translation provides a useful tool for laboratory validation of sperm separation by flow sorting technology. Moreover, the ease of nick translation and the quality of the fluorescent signal obtained using this method makes this procedure the most appropriate method for labelling pig DNA probes to be used for direct FISH on pig spermatozoa.

Animals↗
PubMed2002

Relationship between antral follicle size, oocyte diameters and nuclear maturation of immature oocytes in pigs.

We designed the present study to examine the possible relationship between oocyte, antral follicle size and the nuclear heterogeneity of immature pig oocytes, in order to study the heterogeneity of oocyte populations in ovaries obtained from slaughterhouses. Previously, we carried out an initial experiment to determine, by histological analysis, the effectiveness of the macroscopic criteria (MC) used to screen atretic and nonatretic antral follicles. We recovered 239 follicles by mechanical dissection, measured them with a computerized image analysis system, and classified them into five size categories according to their diameter (FD): Group 1 (0.40-0.99 mm), Group 2 (1.00-2.19 mm), Group 3 (2.20-2.79 mm), Group 4 (2.80-3.59 mm) and Group 5 (3.60-6.50 mm). In relation to histological analysis, the results showed that MC is an effective method to select atretic and nonatretic antral follicles from 0.40 to 6.50 mm in diameter (overall accuracy was 80.75%, with sensitivity and specificity rates of 79.33 and 82.20%, respectively). In a second experiment, we recovered 454 nonatretic follicles, then measured and classified them as mentioned above. We removed oocytes individually from follicles and measured their size (oocyte diameter without and with zona pellucida, OD and TOD, respectively). Finally, we evaluated the relationship between OD, FD and nuclear maturation of immature oocytes (germinal vesicles (GV) Stages 0, I, II, III and IV; diakinesis, prophase I, and metaphase I). Overall OD was 101.77 +/- 0.65, 109.19 +/- 0.45, 113.55 +/- 0.50, 116.92 +/- 0.46 and 117.13 +/- 0.47 microm (Groups 1, 2, 3, 4, and 5, respectively). Differences in OD between groups were significant (P < 0.01), although from 2.80 to 6.50 mm follicles, the oocytes were not different in size. There was a certain heterogeneity in OD within each follicular group. Although we observed a certain degree of nuclear variability, regardless of FD or OD, the present study showed a clear progression in GV when FD increased from 0.40 to 6.50 mm. A positive correlation (r2 = 0.4248; P > 0.05) was established mainly between the nuclear stage and oocyte diameter.

Animals↗
PubMed2002

Motility characteristics and fertilizing capacity of boar spermatozoa stained with Hoechst 33342.

Flow cytometry sorting of spermatozoa using fluorescence dye Hoechst 33342 is the only effective sex selection methodology validated in numerous laboratories. This study was carried out to determine the effect of Hoechst 33342 on the motility and fertility of stained boar spermatozoa. Experiment 1 evaluated motility parameters (percentage of motile spermatozoa, velocity, angularity and oscillation) of boar spermatozoa stained with Hoechst 33342 by a computer-aided sperm analysis (CASA) instrument. Spermatozoa (30 million/ml) were divided into five treatment groups and stained during 1 h at 35 degrees C with 9, 18, 27, 60 and 90 microM of H33342. There were no differences in sperm motility patterns nor percentages of motile spermatozoa incubated in the presence of 9, 18 or 27 microM. Percentage of motile spermatozoa and motility parameters decreased significantly (p < 0.05) at 60 microM of Hoechst 33342. Spermatozoa were immotile at concentration of 90 microM. In experiment 2, pregnancy rates, farrowing rates and litter size from sows (n = 275) artificially inseminated (AI) with either Hoechst 33342 stained (27 microM) or unstained (control) spermatozoa were determined. Sows inseminated with stained spermatozoa had no significant lower pregnancy rate (88.33%) as compared with controls (90.32%). Staining neither affected farrowing rates (85.0 vs 87.7%) nor total number of piglets born (10.56 +/- 0.32 vs 10.47 +/- 0.24, stained and controls, respectively). No phenotypical abnormalities were registered among the newborn piglets. The data suggest that incubating spermatozoa with Hoechst 33342 at levels required for X- and Y-bearing chromosome sperm sorting, does not impair sperm viability or their fertility after AI.

Animals↗