PubMed Health⌕ Search

Biomedical subjects

D Planelles

Publications and source records attributed to D Planelles.

17 recordsLinked to original sources

HLA class II polymorphisms in Spanish melanoma patients: homozygosity for HLA-DQA1 locus can be a potential melanoma risk factor.

BACKGROUND: The association of melanoma with HLA class II loci is under extensive debate. Different investigators have found discrepant results due to, at least in part, sample size, patient series heterogeneity, choice of control population and differences in the techniques employed for the detection of HLA antigens and alleles. OBJECTIVES: This study was designed to analyse the possible association of melanoma with HLA class II loci with regard to different clinic pathological factors and to investigate other risk factors for melanoma susceptibility, such as HLA homozygosity. PATIENTS AND METHODS: HLA-DRB1, -DQA1 and -DQB1 genotyping was performed for 117 eastern Spanish patients presenting with primary melanoma. RESULTS: Although there were no significant alterations in the phenotypic frequencies of HLA-DQA1, -DQB1 or -DRB1 alleles in any subgroup of patients when compared with controls, patients exhibited a statistically significant increase in HLA-DQA1 homozygosity rate. This DQA1 homozygosity-specific association was particularly dependent on some features in melanoma patients such as light hair colour, skin type I or II, early age at diagnosis, absence of atypical naevi, or abscence of atypical naevus syndrome phenotype (aetiological fractions about 10-20%). Analysis of homozygosity for single DQA1 alleles showed an increased homozygosity rate for DQA1*0505 and DQA1*0301 in comparison with controls. These DQA1 alleles are in strong linkage disequilibrium with DQB1*0301 in white populations, and DQB1*0301 homozygous individuals were significantly increased in red in or fair-haired patients (relative risk 5.65). CONCLUSIONS: Our results indicate that the contribution of HLA class II alleles to primary melanoma incidence is not significant in the Spanish population. However, homozygosity for the HLA-DQA1 locus (and, perhaps, for the HLA-DQB1*0301 allele) might be considered a potential risk factor for developing melanoma depending on the person's genetic background and, perhaps, on certain environmental conditions.

Adult↗

Optimizing donor selection in a cord blood bank.

OBJECTIVES: The main limitation factor for the wide use of umbilical cord blood (UCB) as a source of hematopoietic progenitor for transplantation is cell dose. One of the specific areas identified by some studies for improvement of UCB collection is donor selection. METHODS: Over a 3-mth period, 391 consecutive maternal-neonatal pairs were evaluated during the pre-partum period in the maternity ward at La Fe University Hospital (Valencia) by the Cord Blood Bank staff. Reasons for discarding umbilical cord blood donors and collected UCB units at the Cord Blood Bank in Valencia have been analysed. Obstetric factors influencing TNC content of 1300 collected UCB units have been determined, in order to establish obstetric criteria for cord blood donors selection in our geographic area. RESULTS: Only 32.5% of potential cord blood donors were refused. Among 1300 UCB collected, 506 (38.9%) were discarded before cryopreservation, mainly due to low cell counts. Multivariate analyses showed that the main significant factors influencing nucleated cell count were the weight of the placenta, sex of newborn and mode of collection. CONCLUSIONS: Our study shows that maternal medical histories must be completely reviewed by medical staff before collection of the UCB. Obstetrical factors influence cell content of UCB and could be added to standard cord blood donor criteria in order to improve the bank efficiency.

Antigens, CD↗

Utility of bag segment and cryovial samples for quality control and confirmatory HLA typing in umbilical cord blood banking.

Many cord blood (CB) banks have been established worldwide as a response to the increasing number of CB transplantations. In this study, we describe a quality control program in which the utility of an integral bag segment and cryovial containing aliquots of cryopreserved product as haematopoietic content control and HLA typing confirmation for CB units has been evaluated. For this purpose, every month one stored CB unit and its satellite cryovials were thawed and washed. Nucleated cell counts, viability and clonogenic assays were performed from the bag and cryovial before washing. After washing, total nucleated cell, CD34+ counts, viability, and clonogenic assays were performed from the bag. In order to assure the ability of bag segments to confirm hematopoietic potential of CB units, clonogenic assays and viability were performed from attached segments of 10 CB units and the results were compared with those from bags and cryovials. When comparing all variables between thawed bag and cryovial samples, they showed similar results. Mean colony-forming unit (CFU) content of segment samples was 118.8 +/- 93.72 x 10(4) that resulted similar to bags and cryovials haematopoietic content. In conclusion, the quality control system described in this paper demonstrates that CB units are processed preserving the quantity and quality of the progenitor cells. The contiguous segment haematopoietic content is representative of the final product.

Blood Banks↗

Comparison between two cord blood collection strategies.

BACKGROUND AND OBJECTIVES: Collection strategy is the first step for collecting good quality cord blood (CB) units. There are two principal different techniques to collect CB from the umbilical vein: in the delivery room while the placenta is still in the uterus by midwives and obstetricians or in an adjacent room after placental delivery by CB-bank trained personnel. In this study, the benefits and disadvantages between two different CB collection strategies were evaluated in order to improve CB bank methodology. DESIGN AND METHODS: Valencia CB bank maintains the two different collection strategies aforementioned. Before processing CB units, volume was calculated and samples were drawn for cell counts. After processing and before cryopreservation, samples for cell counts, CD34 analysis, viability, clonogenic assays and microbiology were drawn directly from the bags. We compared the efficiency of the two collection techniques. RESULTS: Obstetric date and umbilical CB was obtained from 848 vaginal (484 collected in uterus and 364 collected ex uterus). The proportion of excluded CB units before processing was 33% for ex uterus and 25% for in uterus. The difference was statistically significant. A larger volume and a higher number of total nucleated cells, CD34+ cells and CFUs were harvested in the in uterus collection group. INTERPRETATION AND CONCLUSIONS: Based on our findings, we conclude that the mode of collection influences the hematopoietic content of CB donations. Collection before placental delivery is the best approach to CB collection and allows optimizing CB bank methodology.

Antigens, CD34↗

Comparison between two strategies for umbilical cord blood collection.

The use of cord blood (CB) for transplantation has increased greatly in recent years. The collection strategy is the first step in collecting good-quality CB units. There are two main techniques for collecting CB from the umbilical vein: in the delivery room while the placenta is still in the uterus by midwives and obstetricians or in an adjacent room after placental delivery by CB bank trained personnel. In this study, the benefits and disadvantages between the two different CB collection strategies were evaluated, in order to improve CB bank methodology. Valencia CB bank maintains the two different collection strategies. CB was obtained from 569 vaginal and 70 caesarean deliveries and obstetrical and clinical charts were reviewed. Before processing CB units, volume was calculated and samples were drawn for cell counts. After processing and before cryopreservation samples were drawn for cell counts, CD34+cell analysis, viability, clonogenic assays and microbiology were drawn directly from the bags. We compared the efficiency of the two collection techniques. Obstetric data and umbilical CB were obtained from 569 vaginal (264 collected in utero and 305 collected ex utero) and 70 caesarean deliveries. The proportion of excluded CB units before processing was 33% for vaginal ex utero, 25% for vaginal in utero and 46% for caesarean deliveries. Differences were statistically significant. For vaginal deliveries a larger volume and a higher number of nucleated cells, percentage of CD34+ cells and colony-forming units (CFUs) were harvested in the in utero collection group. There was no statistical difference between CB collected after placental expulsion from vaginal and caesarean deliveries. Comparison between all vaginal and caesarean deliveries did not show any difference. We conclude that the mode of collection influences the haematopoietic content of CB donations. Collection before placental delivery is the best approach to CB collection and allows optimisation of CB bank methodology. Caesarean deliveries seem to contain similar progenitor content to vaginal deliveries.

Adult↗

Standardized, unrelated donor cord blood transplantation in adults with hematologic malignancies.

The potential role of unrelated donor cord blood transplantation (UD-CBT) in adults remains unclear. This study reports the results of UD-CBT in 22 adults with hematologic malignancies following conditioning with thiotepa, busulfan, cyclophosphamide, and antithymocyte globulin in 21, with thiotepa, fludarabine, and antithymocyte globulin in 1, and graft-versus-host disease (GVHD) prophylaxis with cyclosporine and prednisone. Median age was 29 years (range, 18-46 years), and median weight was 69.5 kg (range, 41-85 kg). HLA match was 6 of 6 in 1 case, 5 of 6 in 13 cases, and 4 of 6 in 8 cases. Median number of nucleated cells infused was 1.71 x 10(7)/kg (range, 1.01 x 10(7)/kg to 4.96 x 10(7)/kg). All 20 patients surviving more than 30 days had myeloid engraftment, and only 1, who received the lowest cell dose, developed secondary graft failure. Median time to reach an absolute neutrophil count of at least 0.5 x 10(9)/L was 22 days (range, 13-52 days). Median time to platelets numbered at least 20 x 10(9)/L was 69 days (range, 49-153 days). Seven patients (32%) developed acute GVHD above grade II, and 9 of 10 patients at risk developed chronic GVHD, which became extensive in 4 patients. Twelve patients remained alive and disease-free 3 to 45 months after transplantation. Disease-free survival (DFS) at 1 year was 53%. Age strongly influenced DFS (P =.01). For patients aged 30 years or younger, the DFS at 1 year was 73%. These preliminary results suggest that UD-CBT should be considered a reasonable alternative in young adults with hematologic malignancy and no appropriate bone marrow donor.

Adult↗

Unrelated donor cord blood transplantation in adults with chronic myelogenous leukemia: results in nine patients from a single institution.

The potential role of unrelated donor cord blood transplantation (UD-CBT) in adults is not well established. We report the results of UD-CBT in nine adult patients with chronic myeloid leukemia (CML). The median age was 27 years (range, 19-41 years), and the median weight was 62 kg (range, 45-78 kg). At transplant, six patients were in chronic phase (five in first, and one in second), two in blast crisis, and one in accelerated phase. Eight had received intensive chemotherapy, and three had undergone autologous peripheral blood hematopoietic stem cell transplantation. Four had received interferon with no cytogenetic response, and only three underwent UD-CBT within 1 year of diagnosis. After serological typing for class I antigens, and high-resolution DNA typing for DRB1, the degree of HLA match between patients and cord blood (CB) units was 4/6 in six cases and 5/6 in three cases. The median number of nucleated cells infused was 1.7 x 10(7)/kg (range, 1.2 to 4.9 x 10(7)/kg), and was above 2 x 10(7)/kg in only two cases. All patients received thiotepa, busulfan, cyclophosphamide and anti-thymocyte globulin as conditioning; cyclosporine and prednisone for graft-versus-host disease (GVHD) prophylaxis; and G-CSF from day +7 until engraftment. All seven evaluable cases engrafted. The median time to reach an absolute neutrophil count > or =0.5 x 10(9)/l and > or =1 x 10(9)/l was 22 days (range, 19-52 days) and 28 days (range, 23-64 days), respectively. In the four patients evaluable for platelet recovery time to levels of > or =20 x 10(9) platelets/l, > or =50 x 10(9) platelets/l, and > or =100 x 10(9) platelets/l, these ranged from 50 to 128 days, 60 to 139 days, and 105 to 167 days, respectively. Three patients developed acute GVHD above grade II, and three of the five patients at risk developed extensive chronic GVHD. Four patients, all transplanted in chronic phase, remain alive in molecular remission more than 18, 19, 24 and 42 months after transplantation. These preliminary results suggest that UD-CBT may be considered a reasonable alternative in adults with CML who lack an appropriate bone marrow donor.

Acute Disease↗

HLA-DQA, -DQB and -DRB allele contribution to narcolepsy susceptibility.

The association of narcolepsy with HLA class I antigens and HLA class II alleles was studies in a series of Spanish narcoleptic patients. The haplotype DRB1*1501-DRB5*0101-DQA1*0102-DQB1*0602 was found to be significantly associated with the disease, while the haplotype DRB1*0701-DRB4*01-DQA1*0201-DQB1*02 might confer a slight protective effect against narcolepsy. Gene dose-effect was not seen in any of the involved alleles, and linkage disequilibrium between the positively associated alleles was found to be stronger in patients than in controls. Statistical analysis applied to identify the HLA allele truly responsible for the association did not clearly discriminate between the contribution of DRB1*1501 and that of DQB1*0602, but it proved that the association with DQA1*0102 is secondary to that with DRB1*1501/DQB1*0602. Analysis of the diagnostic value of typing for the narcolepsy-associated alleles demonstrated a very high negative predictive value and revealed that this test can be convenient for exclusion of narcolepsy in cases when the diagnosis is not evident after clinical evaluation and the marker haplotype is absent. Finally, a family study indicated that narcolepsy is a multifactorial disorder that involves HLA genes under an incomplete penetrance model, with possible influences from environmental factors or other genes different to HLA genes.

Adolescent↗

A new, fast, and simple DNA extraction method for HLA and VNTR genotyping by PCR amplification.

In the present study a new DNA extraction method is described. The new protocol, which uses caprylic acid for isolating DNA, is technically simple and very fast, as it enables us to obtain DNA from peripheral blood in only 10 minutes. Moreover, DNA preparations obtained with this procedure can be effectively used for HLA class II and variable number tandem repeat genotyping by polymerase chain reaction, so the new method is well suited for routine clinical use in any type of analysis requiring DNA typing for individual characterization.

Caprylates↗

Effects of nordihydroguaiaretic acid on murine antibody-dependent cellular cytotoxicity.

The purpose of this study was to analyze the effects of nordihydroguaiaretic acid, an inhibitor of the lipoxygenase pathway of arachidonic acid, on antibody-dependent cellular cytotoxicity. Antibody-dependent cellular cytotoxicity mediated by murine spleen cells was significantly inhibited by concentrations of nordihydroguaiaretic acid from 10(-5) to 10(-4) M (1C50 = 2 x 10(-5) M). The inhibitory effect of nordihydroguaiaretic acid was also observed on antibody-dependent cellular cytotoxicity mediated by macrophage-depleted spleen cells as well as isolated macrophages. Nordihydroguaiaretic acid was highly effective when added at the beginning of the assay and was always present throughout the assay, but failed to inhibit the binding of effector and target cells. The inhibition produced by nordihydroguaiaretic acid could not be reversed by leukotriene B4, a 5-lipoxygenase product. These results suggest that arachidonic acid metabolites other than leukotriene B4 are released by different populations of spleen cells to positively regulate important events in the postbinding phase of murine antibody-dependent cellular cytotoxicity.

Animals↗

Seasonal variation in proliferative response and subpopulations of lymphocytes from mice housed in a constant environment.

A seasonal variation in the proliferative response to mitogens and in the proportion of splenic lymphocyte subpopulations was found in mice housed in a constant environment. The lymphoproliferative responses to T-cell and B-cell mitogens reached maximum values in autumn and summer. Identification of lymphocyte subpopulations by flow cytometry demonstrated that the proportion of T cytotoxic-suppressor (Tcs) lymphocytes was significantly higher in autumn and summer than in spring and winter. However, the proportion of B lymphocytes was significantly lower in spring than in the other three seasons, whereas the proportions of T and T helper (Th) cells did not show any seasonal variation. On the other hand, we observed a significant correlation between the level of mitogenic responsiveness and the proportion of Tcs cells, but not between the former and the proportions of B, T or Th cells. These data suggest that the seasonal variation in murine lymphoproliferative responses may depend on the cyclic changes in the proportion of Tcs lymphocytes; these changes, in turn, may be predetermined by the inherent internal biological rhythms of the animal.

Animals↗

Differential effects of the calcium ionophore A23187 and the phorbol ester PMA on lymphocyte proliferation.

The effects of the phorbol ester, phorbol-12-myristate-13-acetate (PMA), and of the calcium ionophore A23187 on DNA synthesis in murine quiescent and mitogen-stimulated lymphocytes have been examined. Neither PMA nor A23187 had any mitogen effect on their own on quiescent lymphocytes. However, stimulation of cells sequentially with A23187 and then PMA resulted in a proliferative response in proportion to the duration of the exposure to A23187, and the sustained simultaneous presence of both agents was necessary for maximum proliferation. On the other hand, while short incubations with A23187 potentiated mitogen-induced DNA synthesis, prolonged exposure inhibited it. Furthermore, on lymphocytes stimulated with two T cell mitogens, the effects of A23187 and PMA depended on the proliferation-inducing mitogens and the responsiveness level induced by them. Therefore, while PMA and short pretreatments with A23187 had no effect on high intensity mitogenic responses, low intensity responses were significantly enhanced. These results demonstrate differential effects of A23187 and PMA on DNA synthesis that should be useful in studies on the mechanisms of activation of lymphocyte proliferation.

Animals↗

Effects of lipoxygenase and cyclooxygenase inhibitors on murine antibody-dependent cellular cytotoxicity (ADCC).

The purpose of this study was to determine the effects that specific inhibition of arachidonic acid (AA) metabolism has on the antibody-dependent cellular cytotoxicity (ADCC) of murine spleen cells. The action of three inhibitors of the lipoxygenase (LO) pathway--nordihydroguaiaretic acid (NDGA), esculetin (Es), and phenanthroline (Phe)--was compared with that of three inhibitors of the cyclooxygenase (CO) pathway--indomethacin (INDO), acetyl salicylic acid (ASA), and imidazole (IMI). All the LO inhibitors suppressed ADCC function in a dose-dependent manner, but NDGA was the most potent inhibitor of this cytolytic activity. In fact, NDGA inhibited the ADCC function with 97% inhibition at 100 microM, while Phe and Es, at the same concentration, inhibited ADCC by 21% and 19%, respectively. However, CO inhibitors did not markedly affect ADCC function and only some doses of them had a slight, but significant, depressing effect (8-11% inhibition at 0.01-0.1 microM of INDO, 7% inhibition at 400 microM of ASA, and 13% inhibition at 800-1000 microM of IMI). These results suggest the LO pathway of the arachidonic acid metabolism plays an important role in regulating ADCC activity of murine spleen cells and the products of the CO pathway have little effect on ADCC lysis.

Animals↗

Autoantibodies in splenectomized patients as a consequence of abdominal trauma.

The presence of autoantibodies was examined in 100 adult patients splenectomized because of abdominal trauma and without systemic disease, and the results were compared with those observed in a healthy control group. Thirty-seven percent of the patients studied presented some type of autoantibody. Those observed were antinuclear, anti-smooth muscle and, in 1 case, anti-reticulin. Patients with antinuclear antibodies have no antibodies against native DNA, but in 5 cases, anti-Ro (SS-A) and anti-La (SS-B) antibodies were observed. Rheumatoid factors were also found, but their incidence was similar in patients and controls. The incidence of autoantibodies proved not to be related to either the period of time since splenectomy or to age of the patient; they were observed in patients many years after splenectomy and in individuals of both sexes and all ages. Although the presence of autoantibodies seemed to have no effect on our patients, all of whom were asymptomatic, it is important to be aware of this phenomenon when evaluating the laboratory results obtained from splenectomized patients.

Abdominal Injuries↗

Changes in total serum IgE concentrations after splenectomy.

In addition to allergic diseases, there are other disorders that can be accompanied by increased levels of total serum IgE. It has been demonstrated that splenectomy can alter the serum concentrations of other immunoglobulins. The aim of this study was to examine the concentrations of total IgE in the serum of patients splenectomized as a result of abdominal trauma but with no associated disease. Our results show that the average concentrations in the serum of patients were significantly higher that in the control group. Furthermore, in a large number of patients, the concentrations were above the normal limit set for the nonatopic Spanish population. These results suggest that splenectomy can alter the regulation of IgE concentrations. Since total IgE is usually determined for diagnostic purposes, it is useful to be aware of this anomaly when dealing with splenectomized patients in order to interpret correctly the laboratory analyses.

Adolescent↗