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C Martín

Publications and source records attributed to C Martín.

At least 73 records · Page 4Linked to original sources
PubMed1999

Cutaneous hyalohyphomycosis caused by Paecilomyces lilacinus in an immunocompetent host successfully treated with itraconazole: case report and review.

Paecilomyces lilacinus is an emerging fungal pathogen that is highly resistant to many antifungal drugs. Skin and subcutaneous soft tissue infections caused by this organism are very unusual. Most cases occur in patients with impaired host defenses or following surgical procedures. There has been only one previous report of a histologically confirmed cutaneous infection due to Paecilomyces lilacinus in a patient without predisposing factors. Described here is the second histopathologically proven case of Paecilomyces lilacinus cutaneous infection in a healthy patient without any apparent portal of entry. Prolonged antifungal chemotherapy with itraconazole led to resolution of the skin lesion. This case of sporadic cutaneous infection due to Paecilomyces lilacinus is believed to be the first reported in Europe and the first histopathologically proven case successfully treated with itraconazole.

Adult↗
PubMed1999

A new enzyme electrode for quantification of salicylic acid in a FIA system.

This work presents an amperometric biosensor incorporated into a flow configuration comprising salicylate hydroxylase that catalyses the irreversible hydroxylation of salicylate to catechol in the presence of NADH and molecular oxygen, and tyrosinase that further oxidises catechol giving o-quinone which is electrochemically reduced at -100 mV vs. Ag/AgCl yielding catechol and entering the catalytic oxidation and electrochemical reduction cycling which results in signal amplification and, consequently, low limits of detection. Additional incorporation of glucose dehydrogenase in the enzymatic sequence results in regeneration of NADH provided that glucose is present in the carrier stream and incorporation of a dialysis membrane provides operational stability to the biosensor. The analytical characteristics of this catalytic and electrochemical transduction sequence in a FIA system are: a limit of detection of 3.5 10(-6) M (S/N = 3), a sensitivity of 22.6 nA microM(-1) cm(-2), no loss of response at least after 5 h of continuous operation, and a sample frequency of 15 h(-1). Monitoring of salicylate after ingestion of 500 mg of acetylsalicylic acid has been followed in non-pretreated urine samples and the amount of salicylate in several drugs has been also successfully quantified.

Biosensing Techniques↗
PubMed1999

Influence of propylene glycol and isopropyl myristate on the in vitro percutaneous penetration of diclofenac sodium from carbopol gels.

The influence of propylene glycol (PG) on the in vitro penetration of diclofenac sodium (DFS) through a synthetic membrane and abdominal rat skin from carbopol gels was investigated using Franz-type diffusion cells. The combined effect of isopropyl myristate (IPM) and PG was also evaluated. It was found that the penetration through the synthetic membrane was well described by the Higuchi model. The gel containing 40% PG showed the highest release rate, indicating that a releasing maximum exists for PG content which provides the fully solubilized drug in the vehicle. When using rat skin as the barrier, the penetration rate was controlled by the membrane. DFS flux decreased with increasing PG content of the gels due to an increase of the drug affinity to the vehicle. A cosolvent action of PG was evident. However, the combination of PG and IPM resulted in a synergistic enhancement of DFS flux. Maximum enhancing activity was obtained from gels containing 40% PG, which yielded an enhancement ratio of about 8. Increasing IPM content from 3 to 5% increased the flux and decreased the lag time taken to reach a steady-state level.

Acrylic Resins↗
PubMed1999

Influence of polyethylene glycol 4000 on the polymorphic forms of diflunisal.

The present study was carried out to investigate the physico-chemical characteristics of diflunisal-PEG 4000 solid dispersions prepared by melting, solvent and melting-solvent methods. The solvents chosen were chloroform, methanol and ethanol-water due to the fact that the drug presents different polymorphic forms in these solvents. The characterization of solid dispersions was performed by X-ray powder diffraction because this technique has the advantage over other identification methods that it can detect both drug and ligand simultaneously. The X-ray diffraction patterns of the diflunisal-PEG systems suggested that the drug/polymer ratio and the solvent nature play an important role in the crystallization of the drug. In this regard, diflunisal crystallizes in form I at high concentrations of the drug (drug/polymer 2:1) in the solidified melt dispersions, however, polymorph III is mainly obtained as the polymer content increases (1:1 and 2:3). Likewise, in solid systems obtained by the solvent and melting solvent methods the drug solidifies in form III in ethanol/water and methanol while polymorph IV crystallizes in chloroform. Finally, DSC thermograms and hot-stage microscopy data of solid dispersions prepared by the melting method have allowed to draw the diflunisal-PEG 4000 solid-liquid phase diagram.

Calorimetry, Differential Scanning↗
PubMed1999

Bilateral lymphocytic alveolitis: a common reaction after unilateral thoracic irradiation.

The main aim of the present study was to assess the early diagnostic value of bronchoalveolar lavage (BAL) in radiation-induced lung injury in patients with breast carcinoma. Twenty-six females receiving postoperative radiotherapy for breast cancer were evaluated before and 0, 15, 30, 60, and 180 days after radiotherapy. History, physical examination, chest radiographs, and pulmonary function tests were obtained. BAL, including lymphocyte subsets analysis, was limited to the second evaluation after radiotherapy. A group of 21 healthy females were used as control. Findings after radiotherapy in asymptomatic patients were compared with findings in a group of patients with radiation pneumonitis. Irradiated patients showed a significantly (p<0.01) greater percentage (29.5+/-15.7%) of BAL lymphocytes than controls (6.2+/-3.3%). No statistical differences existed in BAL findings between the irradiated and unirradiated sides of the chest. Percentages of BAL lymphocytes did not differ significantly between patients who developed subsequent pneumonitis (24.5+/-13.5%) and those who did not develop pneumonitis (32.8+/-16.5%). Patients with pneumonitis at the time of BAL had significantly higher (p<0.05) alveolar CD4 subset cells (24.8+/-10.2%) than asymptomatic patients (15.2+/-8.9%). Maximal reductions in total lung capacity (p<0.01), and residual volume (p<0.05) occurred 60 days after irradiation. The early lymphocytic alveolitis induced by unilateral thoracic radiotherapy in most patients with breast cancer is always bilateral and does not predict the subsequent development of radiological evidence of pneumonitis.

Breast Neoplasms↗
PubMed1999

Genetic, phenotypic and clinical features of acute lymphoblastic leukemias expressing myeloperoxidase mRNA detected by RT-PCR.

Myeloperoxidase (MPO) is found in the azurophilic granules of normal myelocytic cells. Cytochemical staining for MPO activity is used clinically to distinguish myeloid from acute lymphoid leukemias (ALL). However, using a highly sensitive RT-PCR technique, it is possible to detect MPO mRNA in otherwise clear ALL. The significance of this finding remains poorly understood. We have extended our observations to a series of 57 patients with the primary diagnosis of ALL (46 patients tested at diagnosis and 11 cases at relapse). We identified 25 cases (43.8%) of MPO mRNA(+)/enzyme(-) ALL (17 B cell and eight T cell lineage). Expression of myeloid antigens (CD13 or CD33) were detected in nine of them, and remarkably, 18 cases (72%) displayed CD34. Of these 25 MPO mRNA(+) leukemias, 10 (40%) are Bcr-Abl positive (with P210 fusion transcript in five patients while the five remaining cases carried P190 transcript). Moreover, 11 of 16 myeloid negative cases were also negative for any type of Bcr-Abl and MLL rearrangement, indicating that MPO mRNA positivity is not either invariably related to that chromosomal abnormality or necessarily associated with the presence of other myeloid differentiation features. Interestingly, six of these 11 cases are T-ALL, suggesting the presence of some overlapping phase for T and myeloid lineage commitment. Taken together, these findings could suggest a separate biological disease with immature origin and bipotential differentiation capability, which involves B and T-ALL subtypes and should lead to new investigations regarding their prognostic impact.

Adolescent↗
PubMed1999

Comparison of methods based on different molecular epidemiological markers for typing of Mycobacterium tuberculosis complex strains: interlaboratory study of discriminatory power and reproducibility.

In this study, the currently known typing methods for Mycobacterium tuberculosis isolates were evaluated with regard to reproducibility, discrimination, and specificity. Therefore, 90 M. tuberculosis complex strains, originating from 38 countries, were tested in five restriction fragment length polymorphism (RFLP) typing methods and in seven PCR-based assays. In all methods, one or more repetitive DNA elements were targeted. The strain typing and the DNA fingerprint analysis were performed in the laboratory most experienced in the respective method. To examine intralaboratory reproducibility, blinded duplicate samples were included. The specificities of the various methods were tested by inclusion of 10 non-M. tuberculosis complex strains. All five RFLP typing methods were highly reproducible. The reliability of the PCR-based methods was highest for the mixed-linker PCR, followed by variable numbers of tandem repeat (VNTR) typing and spoligotyping. In contrast, the double repetitive element PCR (DRE-PCR), IS6110 inverse PCR, IS6110 ampliprinting, and arbitrarily primed PCR (APPCR) typing were found to be poorly reproducible. The 90 strains were best discriminated by IS6110 RFLP typing, yielding 84 different banding patterns, followed by mixed-linker PCR (81 patterns), APPCR (71 patterns), RFLP using the polymorphic GC-rich sequence as a probe (70 patterns), DRE-PCR (63 patterns), spoligotyping (61 patterns), and VNTR typing (56 patterns). We conclude that for epidemiological investigations, strain differentiation by IS6110 RFLP or mixed-linker PCR are the methods of choice. A strong association was found between the results of different genetic markers, indicating a clonal population structure of M. tuberculosis strains. Several separate genotype families within the M. tuberculosis complex could be recognized on the basis of the genetic markers used.

Bacterial Typing Techniques↗
PubMed1999

Paclitaxel resistance in non-small-cell lung cancer associated with beta-tubulin gene mutations.

PURPOSE: The mechanisms that cause chemoresistance in non-small-cell lung cancer (NSCLC) patients have yet to be clearly elucidated. Paclitaxel is a tubulin-disrupting agent that binds preferentially to beta-tubulin. Tubulins are guanosine triphosphate (GTP)-binding proteins. Beta-tubulin is a GTPase, whereas alpha-tubulin has no enzyme activity. We reasoned that polymerase chain reaction (PCR) and DNA sequencing of the beta-tubulin gene could reveal more information regarding the connection between beta-tubulin mutations and primary paclitaxel resistance. PATIENTS AND METHODS: Constitutional genomic DNA and paired tumor DNA were isolated from 49 biopsies from 43 Spanish and six American stage IIIB and IV NSCLC patients who had been treated with a 3-hour, 210 mg/m(2) paclitaxel infusion and a 24-hour, 200 mg/m(2) infusion, respectively. Oligonucleotides specific to beta-tubulin were designed for PCR amplification and sequencing of GTP- and paclitaxel-binding beta-tubulin domains. RESULTS: Of 49 patients with NSCLC, 16 (33%; 95% confidence interval [CI], 20.7% to 45.3%) had beta-tubulin mutations in exons 1 (one patient) or 4 (15 patients). None of the patients with beta-tubulin mutations had an objective response, whereas 13 of 33 (39.4%; 95% CI, 22.8% to 56%; P = 0.01) patients without beta-tubulin mutations had complete or partial responses. Median survival was 3 months for the 16 patients with beta-tubulin mutations and 10 months for the 33 patients without beta-tubulin mutations (P =.0001). CONCLUSION: We have identified beta-tubulin gene mutations as a strong predictor of response to the antitubulin drug paclitaxel; these mutations may represent a novel mechanism of resistance and should be examined prospectively in future trials of taxane-based therapy in NSCLC.

Adult↗
PubMed1999

A novel anti-apoptosis gene: Re-expression of survivin messenger RNA as a prognosis marker in non-small-cell lung cancers.

PURPOSE: The survivin gene is a novel apoptosis inhibitor, related to the baculovirus gene, which is believed to play a pivotal role in fetal development and in cancer. We hypothesised that survivin would be expressed in tumors of patients with non-small-cell lung cancer (NSCLC), and we attempted to determine the influence of survivin re-expression on clinical outcome in patients with up to stage IIIA NSCLC who had undergone radical surgery. METHODS: We designed a reverse transcriptase polymerase chain reaction (RT-PCR) assay to study the expression of the survivin gene in 83 NSCLC tumor samples and compared the results with relevant clinical and pathologic data. RESULTS: The RT-PCR identified survivin gene transcript in 71 (85. 5%) of the tumor samples and in only 10 (12%) of the paired, histopathologically normal lung samples. There was no relationship between histologic subtype (squamous v nonsquamous) and survivin gene expression. The 12 patients without survivin expression had significantly better overall survival than the 71 patients with survivin expression (P =.01 by univariate analysis; relative risk, 2. 1). There was no significant correlation between survivin expression and age, sex, cigarette smoking, histologic subtype, tumor differentiation, tumor size, or the presence of mediastinal lymph node metastases in surgical specimens. CONCLUSION: The survivin gene was expressed in a vast majority of NSCLC tumors. We conclude that survivin transcript is a defining diagnostic marker for NSCLC that may also yield prognostic information and, as an apoptosis inhibitor, be an important target in cancer therapy.

Adult↗
PubMed1998

[Clinical factors that affect the detection of BCR-ABL transcripts after allogenic bone marrow transplantation for chronic myeloid leukemia].

BACKGROUND: To evaluate the relationship between clinical parameters and the ability to detect BCR-ABL-positive cells in a series of 27 long survivor patients after allogeneic bone marrow transplantation (BMT) for chronic myelogenous leukemia (CML). PATIENTS AND METHODS: A total of 78 samples obtained between 1 and 160 months after BMT were analyzed for the presence of the BCR-ABL transcript detected by the reverse-transcription polymerase chain reaction (PCR) using nested primers. Median follow up was 83 months. RESULTS: 16 patients were persistently PCR-positive and 7 patients persistently PCR-negative. The original transcript became negative in four patients. Only two of the positive cases developed hematologic relapse during the period of study. High white blood cell counts before BMT (17.88 vs 10.12 x 10(9)/l; p = 0.008) and immunosuppressive therapy for chronic graft-versus-host disease (p < 0.05) were associated with an increased ability to detect residual BCR-ABL positive cells. CONCLUSIONS: Our data show that most patient are persistently BCR-ABL positive after BMT for CML. If these findings represents a dynamic balance between the tumour burden prior BMT and the immunological capability of the graft must be confirmed in further studies.

Adolescent↗
PubMed1998

Allelic loss on chromosome 18q as a prognostic marker in stage II colorectal cancer.

BACKGROUND & AIMS: Loss of heterozygosity (LOH) on chromosome 18q is frequent in colorectal cancer (CRC) and has been associated with poor prognosis in stage II tumors. This study investigated the frequency of LOH in sporadic CRC and its effect on patient prognosis. METHODS: One hundred forty-four patients were screened for LOH at 18q by polymerase chain reaction using three polymorphic microsatellite markers. RESULTS: Nineteen patients were excluded because their tumors showed microsatellite instability in at least one marker. Of the remaining 125 patients, 121 were informative in at least one marker; 45% (54 of 121) showed 18q LOH. Five-year survival was 42% in those with 18q LOH and 73% in those without 18q LOH (P = 0.008). Multivariate analysis showed that tumor side (P = 0.0001) and 18q LOH (P = 0.01) were the only independent prognostic factors. Examining markers individually showed that only the lost of D18S474 had a significant influence on survival in patients with stage II CRC (P = 0.016). CONCLUSIONS: 18q LOH indicates an unfavorable outcome in patients with stage II CRC. Our results emphasize the importance of the 18q21.1 region, where several tumor-suppressor genes have been mapped. Microsatellite analysis may be useful in identifying high-risk patients who might benefit from adjuvant therapy.

Adult↗
PubMed1998

Autologous peripheral blood stem cell transplantation (PBSCT) mobilized with G-CSF in AML in first complete remission. Role of intensification therapy in outcome.

In order to determine if peripheral blood stem cells (PBSC) collected after priming with G-CSF in AML in first complete remission (CR) can be used for autologous transplantation and to evaluate the efficacy of early intensification therapy as in vivo purging, we studied 35 consecutive patients with AML in first CR. After standard induction and consolidation chemotherapy, 24 of them were treated with one (10 patients) or two (14 patients) cycles of high-dose cytarabine plus etoposide prior to PBSC collection. G-CSF was used as the priming agent. Of the 35 patients scheduled for peripheral blood stem cell transplantation (PBSCT), three relapsed before transplantation, and the 32 remaining underwent PBSCT. High-dose therapy consisted of either total body irradiation plus cyclophosphamide or busulphan plus cyclophosphamide. The median number of CD34+ cells infused was 3.24 x 10(6)/kg (range 0.15-14). The median times to reach a PMN count of 0.5 x 10(9)/l and a platelet count of 50 x 10(9)/l were 12 (8-28) and 30 (11-345) days, respectively. There was no transplant-related mortality. Twelve patients relapsed between 2 and 21 months post-PBSCT. With a median follow-up of 28 months, actuarial disease-free survival (DFS) is 52.41 +/- 9% in the intent-to-treat group and 57.4 +/- 9.8% in patients who underwent PBSCT. The probability of DFS is significantly higher for patients who receive early intensification therapy prior to both PBSC collection and PBSCT as compared with patients that do not: 68.8 +/- 10.27% vs 35.5 +/- 12.6%, P = 0.0418. These results indicate the feasibility of PBSCT in AML using G-CSF-mobilized PBSC. The use of intensification treatment as 'purging in vivo' prior both to collection of PBSC and PBSCT significantly reduces the risk of relapse in this group of patients.

Adolescent↗
PubMed1998

Autologous reconstitution with BCR-ABL-negative haematopoiesis after T cell-depleted allogeneic BMT for CML.

We report a patient with Ph chromosome-positive CML who underwent an HLA-identical T cell-depleted BMT from a sibling donor. DNA polymorphism analysis showed complete donor chimaerism after BMT, followed by mixed chimaerism of granulocytes, natural killer cells and B lymphocytes, with T lymphocytes host-derived at day +120 post BMT. From month +20 haematopoiesis was exclusively of host origin in all cell lineages. RT-PCR was used in order to detect residual disease, but at the time, analysis did not show BCR-ABL transcripts. This case is unusual in that non-malignant stem cells of recipient origin survived the transplant and reconstituted haematopoiesis after BMT. Two years post transplant, no molecular or haematological relapse was documented. The observation that subsequent recipient recovery without molecular relapse implies that, at least in this case, the GVL effect can occur in the absence of donor T cells.

Bone Marrow Purging↗