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Biomedical subjects

J M Hernández

Publications and source records attributed to J M Hernández.

At least 19 recordsLinked to original sources
PubMed2006

Prognostic and biological implications of genetic abnormalities in multiple myeloma undergoing autologous stem cell transplantation: t(4;14) is the most relevant adverse prognostic factor, whereas RB deletion as a unique abnormality is not associated with adverse prognosis.

Fluorescence in situ hybridization (FISH) has become a powerful technique for prognostic assessment in multiple myeloma (MM). However, the existence of associations between cytogenetic abnormalities compels us to re-assess the value of each abnormality. A total of 260 patients with MM at the time of diagnosis, enrolled in the GEM-2000 Spanish transplant protocol, have been analyzed by FISH in order to ascertain the independent influence on myeloma prognosis of IGH translocations, as well as RB and P53 deletions. Survival analyses showed that patients with t(4;14), RB or P53 deletions had a significantly shorter survival than patients without these abnormalities. However, patients with RB deletions without other abnormalities in FISH analysis, displayed a similar outcome to those patients without genetic changes by FISH (46 vs 54 months, P=0.3). In the multivariate analysis the presence of t(4;14), RB deletion associated with other abnormalities, age >60 years, high proportion of S-phase cells and advanced stage of the disease according to the International Staging System retained their independent prognostic influence. In summary, RB deletion as a sole abnormality does not lead to a shortening in the survival of MM patients, whereas t(4;14) confers the worst prognosis in MM patients treated with high-dose chemotherapy.

Adult↗
PubMed2006

Optical absorption and thermoluminescence in single NaCl:Cu crystals exposed to 60Co and UV light.

Optical absorption (OA) and thermally stimulated luminescence measurements were performed on NaCl:Cu+(0.04 and 0.08%) crystals blocks grown by the Czochralski technique. The NaCl:Cu+ crystals were exposed to gamma rays from a 60Co source (0.954-30 kGy) as well as UV radiation. The radiation-induced defects were mainly F, Cu- and Cu+ centres, with absorption bands located at 464, 256.7 and 236 nm, respectively. The absorption bands were found to be independent of the Cu impurity concentration. As the gamma-dose irradiation increased, the absorption band at 256.7 nm decreased while the band at 236.3 nm increased highly along with the 256.7 nm band. The F-centres produced at high gamma-radiation dose while thermally bleached showed an increase of the Cu+ OA bands with a simultaneous decrease of Cu- absorption band. The bleaching with F-light showed the participation of the F centre generated by gamma radiation on the ion valence changes of the doping impurity as well as on the TL phenomenon. The TL measurements in NaCl:Cu crystals with both impurity concentrations demonstrated that the Cu+ concentration has a strong influence on the intensity and shape of the glow peaks.

Cobalt Radioisotopes↗
PubMed2006

Pegylated liposomal doxorubicin, melphalan and prednisone therapy for elderly patients with multiple myeloma.

Melphalan & Prednisone (MP) is considered as the standard therapy for Multiple Myeloma (MM) patients not eligible for high-dose therapy. Here, we report the results of a phase I-II study to evaluate the feasibility and efficacy of the association of PLD to the conventional MP regimen during the first six cycles of the front-line therapy for untreated MM patients older than 70. Thirty patients were included in the study with a median age of 77 years (71-84) and a M/F ratio of 17/13. The phase I of the study demonstrated that the maximum tolerable dose of PLD in this setting was 30 mg/m(2), so it was the final dose evaluated in the study. Twenty-nine patients were valuable for response, which was: complete in 4 (14%) partial in 15 (52%) minor/no changes in 7 (24%) and progressive in 3 (10%). The median progression free survival (PFS) was 24 months. The median overall survival (OS) has not been reached yet, with a 3-year probability for OS and PFS of 52 and 37%, respectively. Haematological toxicity was frequent but usually weak/moderate (grades 1 & 2 of the WHO scale) and it was resolved only with dose delays. Infection was a relatively frequent event (30% of patients), but only in 4 cases it was of grade 3. No cases of palmar-plantar erythrodysesthesia were observed. In conclusion, pegylated liposomal doxorubicin can be safely added to the other chemotherapeutic drugs in the treatment of elderly MM patients, which can be very useful for patients in whom novel agents are not tolerated or inefficient.

Aged↗
PubMed2005

F2-isoprostanes in kidney transplant patients: relationship with inflammatory markers.

This prospective study evaluated the relationship between inflammation and oxidative stress in a group of dialysis patients just before and 3 months after kidney transplantation and compared the results with a control group of healthy subjects. The oxidative stress markers determined were different F2-isoprostane isomers. The inflammatory markers included C-reactive protein, interleukin-6, tumor necrosis factor-alpha, and pregnancy-associated plasma protein A. Forty-three patients were the study group and 50 healthy subjects from a hospital blood bank as controls. The results showed levels of inflammatory and oxidative stress markers to be higher in the dialysis patients than in the control group, although they improved following kidney transplantation. Finally, significant correlations were observed between F2-isoprostane isomers and inflammatory markers.

Adult↗
PubMed2005

Gene expression profile reveals deregulation of genes with relevant functions in the different subclasses of acute myeloid leukemia.

Bone marrow samples from 43 adult patients with de novo diagnosed acute myeloid leukemia (AML)--10 acute promyelocytic leukemias (APL) with t(15;17), four AML with inv(16), seven monocytic leukemias and 22 nonmonocytic leukemias--were analyzed using high-density oligonucleotide microarrays. Hierarchical clustering analysis segregated APL, AML with inv(16), monocytic leukemias and the remaining AML into separate groups. A set of only 21 genes was able to assign AML to one of these three classes: APL, inv(16) and other AML subtype without a specific translocation. Quantitative RT-PCR performed for 18 out of these predictor genes confirmed microarray results. APL expressed high levels of FGF13 and FGFR1 as well as two potent angiogenic factors, HGF and VEGF. AML with inv(16) showed an upregulation of MYH11 and a downregulation of a gene encoding a core-binding factor protein, RUNX3. Genes involved in cell adhesion represented the most altered functional category in monocytic leukemias. Two major groups emerged from the remaining 22 AML: cluster A with 10 samples and cluster B with 12. All the eight leukemias that were either refractory to treatment or that relapsed afterwards were assigned to cluster B. In the latter cluster, CD34 upregulation and serine proteases downregulation is consistent with a maturation arrest and lack of granulocytic differentiation.

Adolescent↗
PubMed2005

Evaluation of the antitumor activity of interleukin-12 in an experimental murine model of colorectal cancer induced by 1,2 dimethyl-hydrazine (DMH).

OBJECTIVE: Interleukin 12 (IL-12) is a cytokine that may enhance the proliferation and cytotoxic activity of T lymphocytes and natural killer (NK) cells. A relationship between extensive intratumoral infiltration of NK cells and longer survival rates in colorectal cancer (CRC) patients was previously noted. Preliminary evidence suggests that the combined administration of IL-12 and IL-2 may produce additive immunomodulatory activity. The purpose of this study was to determine whether the systemic administration of IL-12 (+/- IL-2) may induce an immune response against CRC as induced by 1,2-dimethylhydrazine (DMH). METHODS: Sixty-five 6-week-old Wistar rats were treated with weekly subcutaneous injections of DMH for 26 weeks at a dose of 20 mg/kg of body weight. Once tumoral induction was over, the animals were randomly allocated to one of three groups: I, control; II, intraperitoneal injections of IL-12; III, intraperitoneal injections of IL-12 combined with IL-2. At 30 weeks, all surviving animals were sacrificed. We studied the following parameters in each rat--number of tumors, size of tumors, and total tumoral volume. Tumor samples were studied using the monoclonal antibody CD 57 for the detection of NK cells. The extent of NK infiltration was classified as small, less than 50 NK cells/50 high-power field (HPF); moderate, 50 to 150 NK cells/50 HPF, and extensive, more than 150 NK cells/50 HPF. RESULTS: Thirty-five rats died before completion of the carcinogen exposure, and 30 rats were randomized (10 each group). In group II, 2 animals died during treatment. All rats in groups I and III developed tumors, while in group II two rats (25%) were tumor-free. Moreover, only one rat in group II developed multiple neoplasms, in contrast with group I and group III, where six rats (60%) and seven rats (70%), respectively, had more than one tumor. We found statistically significant differences in the mean number of tumors found in group II when compared to group I (p = 0.028) and group III (p = 0.019). Other parameters measured, such as biggest tumor size and total tumoral volume were found to be lower in group II, although no statistical differences were found between groups. Only 10% of rats in group I showed moderated/extensive NK cell infiltration, vs. 60% of rats in group II (p = 0.077) and 70% in group III (p = 0.02). CONCLUSION: The administration of DMH to rodents provides a reliable and consistent means of inducing CRC that may be suitable for the evaluation of anti-cancer therapies. Our findings suggest that IL-12 is effective against the development of experimental CRC. Its antineoplastic effect could be attributed to the stimulus of this cytokine on the intratumoral infiltration of NK cells.

1,2-Dimethylhydrazine↗
PubMed2005

An analysis of postnatal growth in OF1 mice within an interval of 1-220 days of age.

The body weight growth of OF1 mice, both females and males, from day of birth to 220 days old is studied herein. After comparison of different theoretical models, an extension of Koops's multiphasic functions, the tetraphasic, is proposed as the best choice in so wide a time interval in mouse development. This function has allowed us to take into account different aspects of growth. Coefficients and phases of this function are characterized. The end of the first phase was established at 17 days of age. The second phase finished at 35 days of age in females and at 39 days in males. This difference increased during the third phase: the end of it was at 173 days of age in males, and at 160 days in females. The end of the fourth phase in OF1 mice would be produced after 220 days of age. Inflexion points in every four phases, in females and males, are situated. The biggest weight increase occurred in the second phase in both sexes, specially in males (1.26 g per day). Biological meanings of every phase are also discussed. The short lifetime of rodents have allowed us to study a great number of growth phases in a short period of time. Thus the present analysis could be a good starting point for the study of growth curves in other species of mammals.

Age Factors↗
PubMed2004

Proliferative activity of plasma cells is the most relevant prognostic factor in elderly multiple myeloma patients.

Although multiple myeloma (MM) is predominantly a disease of the elderly, few studies have focused on the identification of prognostic factors in this group of patients. Four hundred twenty five MM patients >65 years were uniformly treated with chemotherapy (MP or VCMP/VBAD). Multivariate analysis identified 4 factors with independent unfavorable prognostic influence: high percentage of S-phase bone marrow plasma cells (>2.5%); elevated beta(2) microglobulin (B2M) (>4 mg/L); age >80 years old; and LDH serum levels (above normal limit). The S-phase value was the most powerful independent prognostic factor to discriminate subgroups of patients with different prognosis. Thus, 3 main risk categories could be identified according to S-phase values: </=1%, 1-3% and >3%, with median survivals of 34, 22 and 12 months, respectively (p < 0.0001). Our study also proved the value for elderly patients of the recently developed International Score System (ISS) based on B2M and albumin. Furthermore, the number of S-phase cells helped to subdivide the ISS III Group identifying a subset of patients with very poor prognosis defined by an additional high S-phase, who displayed a median survival of only 8 months. These results demonstrate that elderly patients can be accurately classified according to prognosis, which may be particularly valuable when comparing the efficacy of new treatment strategies. Moreover, our results underline the high prognostic value of proliferative activity of PC, a parameter that should be considered in routine laboratory investigations of MM.

Age Factors↗
PubMed2004

Limits for the central production of Theta+ and Xi(--)pentaquarks in 920-GeV pA collisions.

We have searched for Theta+(1540) and Xi(--)(1862) pentaquark candidates in proton-induced reactions on C, Ti, and W targets at midrapidity and square root of s = 41.6 GeV. In 2 x 10(8) inelastic events we find no evidence for narrow (sigma approximately 5 MeV) signals in the Theta+ --> pK0(S) and Xi(--) --> Xi- pi- channels; our 95% C.L. upper limits (UL) for the inclusive production cross section times branching fraction B dsigma/dy/(y approximately 0) are (4-16) mub/N for a Theta+ mass between 1521 and 1555 MeV, and 2.5 mub/N for the Xi(--). The UL of the yield ratio of Theta+/Lambda(1520) < (3-12)% is significantly lower than model predictions. Our UL of B Xi(--)/Xi(1530)0 < 4% is at variance with the results that have provided the first evidence for the Xi(--).

Journal Article↗
PubMed2004

The oral combination of thalidomide, cyclophosphamide and dexamethasone (ThaCyDex) is effective in relapsed/refractory multiple myeloma.

We evaluate the efficacy of the oral combination of thalidomide, cyclophosphamide and dexamethasone (ThaCyDex) in 71 refractory/relapsed multiple myeloma patients, including a prognostic analysis to predict both response and survival. Patients received thalidomide at escalating doses (200-800 mg/day), daily cyclophosphamide (50 mg/day) and pulsed dexamethasone (40 mg/day, 4 days every 3 weeks). On an intention-to-treat basis and using the EBMT response criteria, 2% patients reached complete response (CR), 55% partial response (PR) and 26% minor response (MR) yielding a total response (CR+PR+MR) rate of 83% after 3 months of therapy. After 6 months of therapy, responses were maintained including a 10% CR. The 2-year progression free and overall survival were 57 and 66%, respectively. A favorable response was associated with beta2 microglobulin < or =4 mg/dl, platelets >80 x 10(9)/l and nonrefractory disease. Regarding survival, low beta2 microglobulin (< or =4 mg/dl), age (< or =65 years) and absence of extramedullary myelomatous lesion were associated with a longer survival. Major adverse effects included constipation (24%), somnolence (18%), fatigue (17%) and infection (13%). Only 7% of patients developed a thrombo-embolic event. ThaCyDex is an oral regimen that induces a high response rate and long remissions, particularly in relapsing patients with beta2 microglobulin < or =4 mg/dl and < or =65 years.

Administration, Oral↗
PubMed2004

Randomized comparison of dexamethasone combined with melphalan versus melphalan with prednisone in the treatment of elderly patients with multiple myeloma.

Melphalan-prednisone (MP) has been the gold standard treatment for more than 30 years in elderly multiple myeloma (MM) patients. In order to assess whether the combination of dexamethasone with melphalan (MD) could improve on the efficacy of MP, we have carried out a randomized trial comparing both treatment approaches. A total of 201 patients >/=70 years old were included in the study. The overall response rate was similar after six cycles (MP: 67.9%versus MD: 64.5%) and after 12 cycles (MP: 49.4%versus MD: 46.1%). However, the proportion of complete responses (CR) was higher in the MD arm, particularly after 12 cycles (MD: 22.4%versus MP: 9.1%; P < 0.05). There was no significant difference in event-free survival (MP: 15.9 months versus MD: 23.3 months). The median overall survival in both arms was almost identical (MP: 29.4 months versus MD: 27.2 months; P = 0.63). No significant differences in haematological toxicity were observed, but non-haematological toxicity was significantly higher in the MD arm. According to these results MP remains as the gold standard for treatment of MM and should be the reference for comparison of new therapeutic approaches involving novel agents.

Aged↗
PubMed2002

Tight junctions are sensitive to peptides eliminated in the urine.

We prepare an extract of dog urine (DLU) that, when applied to monolayers of MDCK cells (epithelial, derived from a normal dog), enhances the transepithelial electrical resistance (TER) in a dose-dependent manner. This increase is not reflected in variations of the linear amount of TJ nor in changes of the pattern of junctional strands as observed in freeze fracture replicas, nor in the distribution of claudin 1 (a membrane protein of the TJ) nor ZO-1 (a TJ-associated protein). A preliminary characterization of the active component of DLU indicates that it weighs 30-50 kDa, bears a net negative electric charge, and is destroyed by type I protease but not by 10-min boiling. DLUs prepared from human, dog, rabbit and cat are effective on MDCK cells. However, dog DLU increases TER in MDCK (dog) as well as LLCPK1 (pig) monolayers, but not in other epithelial cell lines such as LLCRK1 (rabbit), PTK2 (kangaroo) and MA-104 (monkey), nor in the endothelial cell line CPA47 (cow). Given that in its transit from the glomerulus to the urinary bladder the filtrate increases its concentration by more than two orders of magnitude, the substance(s) we report may act at increasingly higher concentrations in each segment, and afford a potential clue to the progressive increase of TER across the walls of the nephron from the proximal to the collecting duct.

Animals↗
PubMed2002

Estimated risk of transfusion-transmitted viral infections in Spain.

BACKGROUND: Estimates of the risk of transfusion-transmitted viral infections are essential for monitoring the safety of the blood supply. The aim of the present study was to estimate the residual risk of blood-borne viral infections in Spain. STUDY DESIGN AND METHODS: Incidence rates of seroconversion for HIV, HBV, and HCV were calculated among 673,018 persons who donated blood more than once (repeat donors), from 1997 through 1999 at 22 blood donation centers (for a total of 2,464,964 allogeneic blood donations and 1,052,752 person-years). RESULTS: Incidence rates per 100,000 person-years and their 95-percent CIs were as follows: for HBV, 8.36 (5.24-12.62); for HIV, 3.23 (2.24-4.52); and for HCV, 3.70 (2.63-5.07). After adjusting incidence rates for the estimated duration of the infectious window period for each virus, the residual risk per unit transfused was estimated at 1 in 513,000 for HIV, 1 in 74,000 for HBV, and 1 in 149,000 for HCV. The introduction of new screening test based on NAT would have reduced these risks by 27 to 50 percent for HIV, by 42 percent for HBV, and by 62 to 65 percent for HCV. CONCLUSION: The residual risks of transmission of HIV, HBV, and HCV in Spain are similar to those reported in other countries and should be further reduced in the future.

Biomarkers↗
PubMed2001

Reversed-phase high-performance liquid chromatography versus spectrophotometric assay for thimerosal in Cuban recombinant hepatitis B vaccine.

A reversed-phase liquid chromatographic method was applied to study the stability of thimerosal in Cuban recombinant hepatitis B vaccine samples stored under different temperature conditions. Salicylic acid was used as internal standard, it allowed one to determine the thimerosal in the presence of its degradation products. Good stability of the preservative was demonstrated in vaccine samples for as long as 6 years. The same results were obtained when the vaccine samples were incubated at 37 and 45 degrees C during 30 days. The results were in compliance with the microbiological test for determining the effectiveness of antimicrobial preservative in these samples.

Anti-Infective Agents↗
PubMed2001

Identification and characterization by high-performance liquid chromatography/electrospray ionization mass spectrometry of a new variant hemoglobin, Mataro [beta134(H12) Val > Ala.

This work illustrates the practical use of combined microbore reversed-phase high-performance liquid chromatography (RP-HPLC) with electrospray ionization mass spectrometry (ESI-MS) in protein identification. The approach consisted of the detection of the abnormal beta-globin chain by ESI-MS analysis of mixtures of intact globins, which simultaneously provided their molecular masses. Separation of the polypeptide globin chains was carried out using microbore C4 RP-HPLC on-line with ESI-MS. Direct peptide-mapping ESI-MS without previous chromatographic separation was performed in order to identify tryptic peptides from whole blood. For the sequence confirmation of the abnormal peptide containing the mutation point, C18 RP-HPLC tryptic separation of the globin mixture on-line with collision-induced dissociation (CID) fragmentation was done. The y series ions allowed the identification of the hemoglobin (Hb) variant as [beta134(H12) Val > Ala]. This new Hb was named Hb Mataró, after the city where it was detected.

Alanine↗
PubMed2001

Recognition of carbohydrate epitopes specific for electron-dense granule antigens from Entamoeba histolytica by monoclonal antibodies in the cecal content of infected hamsters.

The pathogenic trophozoites of Entamoeba histolytica produce and secrete electron-dense granules (EDG) containing collagenase, considered a virulence factor. Two monoclonal antibodies (MAbs) (L7.1 and L1.1) anti-EDG antigens were raised. MAb L7.1 has been reported to recognize proteic EDG antigens and MAb L1.1 reacted with a carbohydrate epitope. These epitopes were present in axenic and xenic amoebas. To detect EDG antigens by a enzyme-linked immunosorbent assay (ELISA) in a experimental model of early intestinal amoebiasis, both MAbs were employed. E. histolytica HM1 axenic and monoxenic trophozoites were inoculated into the cecum according to the washed-closed cecal loop technique. The cecal content was recovered at 8, 24, and 48 h post-inoculation. Antigens from EDG in whole trophozoites and cell-free supernatants were detected. Our results indicate that it is possible to detect EDG antigens in the cecal content of hamsters in the early phase of the invasive amoebiasis.

Animals↗
PubMed2001

Novel genomic imbalances in B-cell splenic marginal zone lymphomas revealed by comparative genomic hybridization and cytogenetics.

Splenic marginal zone lymphoma (SMZL) has recently been recognized in the World Health Organization classification of hematological diseases as distinct type of non-Hodgkin's lymphoma. In contrast to the well-established chromosomal changes associated with other B-cell non-Hodgkin's lymphoma, few genetic alterations have been found associated with SMZL. The aim of our study was to analyze by comparative genomic hybridization (CGH) the chromosomal imbalances in 29 patients with SMZL and to correlate these findings with clinical and biological characteristics and patient outcome. In 21 cases, cytogenetic studies were simultaneously performed. Most of the patients (83%) displayed genomic imbalances. A total of 111 DNA copy number changes were detected with a median of four abnormalities per case (range, 1 to 12). Gains (n = 92) were more frequent than losses (n = 16), while three high-level amplifications (3q26-q29, 5p11-p15, and 17q22-q25) were observed. The most frequent gains involved 3q (31%), 5q (28%), 12q and 20q (24% each), 9q (21%), and 4q (17%). Losses were observed in 7q (14%) and 17p (10%). SMZL patients with genetic losses had a shorter survival than the remaining SMZL patients (P < 0.05). In summary, chromosomal imbalances in regions 3q, 4q, 5q, 7q, 9q, 12q, and 20q have been detected by CGH in SMZL. Patients with SMZL displaying genetic losses by CGH had a short survival.

Adult↗