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J Maestre

Publications and source records attributed to J Maestre.

At least 19 recordsLinked to original sources
PubMed2003

Lung transplantation in young infants with interstitial pneumonia.

OBJECTIVES: We describe our experience with infants suffering from interstitial pneumonia referred for lung transplantation. METHODS: From April 1998 to December 2000, three infants were admitted to our lung transplantation program: a 9-month-old girl (patient 1) suffering from surfactant protein C deficiency who had high oxygen requirements (fraction of inspired oxygen: 70% to 90%), and two boys, ages 2 (patient 2) and 9 months (patient 3), who were ventilator-dependent due to chronic pneumonitis of infancy. RESULTS: Patients were transplanted at the age of 5 months (patient 2) and 13 months (patients 1 and 3) at 87 to 105 days after being accepted for lung transplantation. All cases underwent a sequential double lung transplant on cardiopulmonary bypass. The immunosuppressive regime included tacrolimus, prednisone, and azathioprine. Patients 2 and 3 also received basiliximab. Two cases suffered a mild rejection episode that responded to high-dose steroids. Patient 2 was ventilator-dependent for 8 months after transplant, owing to severe bronchomalacia and left main bronchus stenosis. Bronchial stenosis resolved after pneumatic dilatation and endobronchial stenting. This patient also presented with a pulmonary artery anastomosis stricture that required percutaneous balloon dilatation. All three patients are at home, carrying out normal activities for their age, with no respiratory symptoms after a period of 8 to 29 months of follow-up. CONCLUSIONS: Interstitial pneumonia of infancy is a rare disease with a bad prognosis and no specific treatment; therefore, lung transplantation represents a good therapeutic option for these infants.

Female↗
PubMed2001

Cerebellar ataxia with anti-glutamic acid decarboxylase antibodies: study of 14 patients.

BACKGROUND: Antibodies to glutamic acid decarboxylase (GAD-Ab) are described in patients with insulin-dependent (type 1) diabetes mellitus (IDDM), in stiff-man syndrome, and, recently, in a few patients with cerebellar ataxia. OBJECTIVES: To show a link between GAD-Ab and some patients with cerebellar ataxia and to clarify their clinical and immunologic profiles. METHODS: Serum samples were selected from 9000 samples of 4 laboratories. The selection criterion was an immunohistochemical pattern compatible with GAD-Ab that was confirmed by radioimmunoassay. We identified 22 patients with stiff-man syndrome and 14 with cerebellar ataxia and GAD-Ab. RESULTS: Thirteen of the 14 patients with cerebellar ataxia and GAD-Ab were women, and 11 had late-onset IDDM. Patients did not have clinical or radiologic evidence of brainstem involvement. Ten patients had oligoclonal IgG bands in the cerebrospinal fluid, and intrathecal GAD-Ab synthesis was observed in 5 of the 6 patients studied. The level of GAD-Ab of these patients was similar to those with stiff-man syndrome and significantly higher than those with IDDM or with polyendocrine autoimmunity (P<.001). However, the GAD-Ab levels of 6 of the 9 patients with polyendocrine autoimmunity overlapped with those of patients with cerebellar ataxia. CONCLUSIONS: These results suggest a link between high level of GAD-Ab and some cases of cerebellar ataxia, particularly women with IDDM. If high serum levels of GAD-Ab are detected, the cerebrospinal fluid should be evaluated for the presence of oligoclonal IgG bands and intrathecal synthesis of GAD-Ab to further prove an autoimmune origin of the syndrome.

Adult↗
PubMed2001

The role of chemotherapy in early non-small-cell lung cancer management.

Great advances have been made in chemotherapy in advanced and metastatic non-small-cell lung cancer (NSCLC), and a major milestone was reached with the administration of neoadjuvant chemotherapy in stage IIIA N2 disease. The systemic nature of lung cancer has been confirmed by many genetic analyses documenting micrometastases in negative lymph nodes and bone marrow, and mRNA gene overexpression as a surrogate of cancer cells has been identified in peripheral blood. Furthermore, serum or plasma cell-free tumor DNA has been observed even in tumors with a diameter of less than 2 cm. Pharmacogenetic screening can lead to tailored chemotherapy even in patients with early disease through the use of a genetic tool kit that will allow us to optimize the use of chemotherapy by using serial measurements of serum DNA that can help to detect residual disease and re-assess the chemosensitivity of sub-clinical micrometastatic disease. The ongoing (neo)adjuvant taxol/carboplatin hope (NATCH) trial is testing the value of three cycles of chemotherapy given pre- or post-operatively compared with surgery alone and will analyze genetic abnormalities in serum DNA at three different points during patient follow-up. Our major concern in this review is to analyze the pros and cons of chemotherapy in NSCLC. Although this review is not a formal meta-analysis, we have discussed the most relevant published studies in this field. We conclude that not only is there no evidence of detrimental effects of chemotherapy, in fact, there are many indications that chemotherapy induces response in up to 80% of patients and downgrades N2 disease in up to 50% of patients. This translates into significantly better survival when accompanied by complete resection. Since at least 50% of patients with stage IB disease develop distant metastases, it seems logical to explore the role of chemotherapy in early disease.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Nebulized amphotericin B prophylaxis for Aspergillus infection in lung transplantation: study of risk factors.

BACKGROUND: Aspergillus infection remains a major cause of morbidity and mortality after lung transplantation. Therefore, some strategies have been attempted, one of which is nebulized amphotericin B (nAB); however, the efficacy of this prophylaxis has not been shown clearly. The aim is to study whether nAB can protect against Aspergillus infection in lung transplant recipients. PATIENTS AND METHODS: A study of risk factors was conducted in 55 consecutive lung allograft recipients. Twenty-three potential risk factors were analyzed. In 44 (80%) patients, nAB was indicated as prophylaxis. Multivariate analysis using logistic regression was performed. RESULTS: Eighteen of the 55 patients (33%) developed infection due to Aspergillus spp. Multivariate analysis showed nAB to be a preventive factor (odds ratio: 0.13; 95% confidence interval [CI] 0.02-0.69; p < 0.05) and cytomegalovirus (CMV) disease was an independent risk factor for developing Aspergillus infection (odds ratio: 5.1; 95% CI 1.35-19.17; p < 0.05). Only 1 patient required withdrawal of the prophylaxis owing to bronchospasm. nAB was well-tolerated in the remaining patients with only a few, mild, easily controlled side effects. CONCLUSIONS: The present results show that nAB prophylaxis may be efficient and safe in preventing Aspergillus infection in lung-transplanted patients, and CMV disease increases the probability of Aspergillus infection.

Adolescent↗
PubMed2000

Isoniazid prophylaxis in lung transplantation.

The incidence of tuberculous disease (TD) is higher in lung-transplant patients than in the general population. During a 7-year period, we included 61 patients who underwent lung transplantation in a prospective isoniazid prophylaxis protocol. Isoniazid was prescribed to infected and anergic patients not previously treated when added to the waiting list. Six of 61 patients (10%) developed tuberculosis. We observed no differences in tuberculous disease incidence between infected-anergic and non-infected patients. In our tuberculous-endemic area, isoniazid prophylaxis is safe and offers protection from TD to infected and anergic patients who must be enrolled in a lung transplantation program.

Adolescent↗
PubMed2000

Human LINE retrotransposons generate processed pseudogenes.

Long interspersed elements (LINEs) are endogenous mobile genetic elements that have dispersed and accumulated in the genomes of higher eukaryotes via germline transposition, with up to 100,000 copies in mammalian genomes. In humans, LINEs are the major source of insertional mutagenesis, being involved in both germinal and somatic mutant phenotypes. Here we show that the human LINE retrotransposons, which transpose through the reverse transcription of their own transcript, can also mobilize transcribed DNA not associated with a LINE sequence by a process involving the diversion of the LINE enzymatic machinery by the corresponding mRNA transcripts. This results in the 'retroposition' of the transcribed gene and the formation of new copies that disclose features characteristic of the widespread and naturally occurring processed pseudogenes: loss of intron and promoter, acquisition of a poly(A) 3' end and presence of target-site duplications of varying length. We further show-by introducing deletions within either coding sequence of the human LINE-that both ORFs are necessary for the formation of the processed pseudogenes, and that retroviral-like elements are not able to produce similar structures in the same assay. Our results strengthen the unique versatility of LINEs as genome modellers.

Animals↗
PubMed2000

Preoperative high-dose cisplatin versus moderate-dose cisplatin combined with ifosfamide and mitomycin in stage IIIA (N2) non small-cell lung cancer: results of a randomized multicenter trial.

Preoperative chemotherapy has become an accepted treatment for stage IIIA (N2) non small-cell lung cancer (NSCLC). The majority of induction regimens employ cisplatin, although the importance of cis-platin dose in combination is unclear. A randomized trial was conducted to address whether higher pre-operative cisplatin doses result in improved survival and increased pathologic complete response in NSCLC. Patients with stage IIIA clinically enlarged and biopsy-proven N2 lesions were randomly assigned to receive either high-dose cisplatin (HDCP) (100 mg/m2) or moderate-dose cisplatin (MDCP) (50 mg/ m2) in combination with ifosfamide (3 g/m2) and mitomycin (6 mg/m2). Disease was restaged after 3 cycles, and those patients with response or stable disease underwent thoracotomy. From March 1993 to February 1997, 83 patients were randomized: 46 received HDCP, and 37 received MDCP. Clinical characteristics were well matched. Radiographic response rate was 59% for HDCP patients and 30% for MDCP patients (P = 0.01). Thoracotomy was performed in 71 patients (86%), 58 of whom had resectable disease. Complete resection rate was 61% in the HDCP group, and 51% in the MDCP group (P = 0.5). Postoperative mortality was 11%. Pathologic complete response was observed in one patient who received MDCP. Median survival in the HDCP and MDCP groups was 13 and 11 months, respectively (P = 0.3). In conclusion, higher radiographic response rate is observed in patients who receive HDCP, but this study fails to show any significant improvement in either overall survival or pathologic complete response in this group of patients.

Clinical Trial↗
PubMed1999

Preresectional chemotherapy in stage IIIA non-small-cell lung cancer: a 7-year assessment of a randomized controlled trial.

In 1989, we began a multicenter study to evaluate the potential benefit of preoperative chemotherapy with cisplatin, ifosfamide and mitomycin over surgery alone in CT-visible N2 non-small-cell lung cancer. We present here a 7-year assessment of this randomized trial. Sixty patients were randomized to receive either surgery alone or three cycles of mitomycin 6 mg/m2, ifosfamide 3 g/m2 and cisplatin 50 mg/m2, given intravenously on day 1 of each cycle at 3-week intervals and followed by surgery. All patients received thoracic irradiation after surgery. The resected tumors were evaluated for the presence of K-ras gene point mutations. Treatment arms were well-balanced in characteristics such as gender, age, histology, and tumor size. Mediastinoscopy and/or mediastinotomy (Chamberlain procedure) with a biopsy was performed in all patients with N2 stage detected by CT scan of the chest (83% of the patients in the preresectional chemotherapy arm and 63% of those in the surgery arm). In eight of the 25 patients (32%) who had mediastinoscopy in the preresectional chemotherapy arm, the initially positive mediastinal lymph nodes were downstaged. For the 30 patients who received preresectional chemotherapy, overall median survival was 22 months (95% CI, 13.4 30.6). Of the 30 patients who received surgery alone, overall median survival was 10 months (95% CI, 7.4-12.6; P = 0.005 by the log rank test). Updated survival data reveals a plateau in the preresectional chemotherapy group, and this still significant long-term survival benefit prompts us to hypothesize that even with short-term preresectional chemotherapy, the natural history of still resectable CT-visible N2 non-small cell lung cancer is favorably altered. The results of our study mirror the long-term survival recently reported in the MD Anderson randomized study.

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↗
PubMed1997

Functional differences between the human LINE retrotransposon and retroviral reverse transcriptases for in vivo mRNA reverse transcription.

We have analysed the reverse transcriptase (RT) activity of the human LINE retrotransposon and that of two retroviruses, using an in vivo assay within mammalian (murine and human) cells. The assay relies on transfection of the cells with expression vectors for the RT of the corresponding elements and PCR analysis of the DNA extracted 2-4 days post-transfection using primers bracketing the intronic domains of co-transfected reporter genes or of cellular genes. This assay revealed high levels of reverse-transcribed cDNA molecules, with the intron spliced out, with expression vectors for the LINE. Generation of cDNA molecules requires LINE ORF2, whereas ORF1 is dispensable. Deletion derivatives within the 3.8 kb LINE ORF2 allowed further delineation of the RT domain: > 0.7 kb at the 5'-end of the LINE ORF2 is dispensable for reverse transcription, consistent with this domain being an endonuclease-like domain, as well as 1 kb at the 3'-end, a putative RNase H domain. Conversely, the RT of the two retroviruses tested, Moloney murine leukemia virus and human immunodeficiency virus, failed to produce similar reverse transcripts. These experiments demonstrate a specific and high efficiency reverse transcription activity for the LINE RT, which applies to RNA with no sequence specificity, including those from cellular genes, and which might therefore be responsible for the endogenous activity that we previously detected within mammalian cells through the formation of pseudogene-like structures.

3T3 Cells↗
PubMed1997

[Toxigenic Vibrio cholerae: identification of the ctxB gene].

BACKGROUND: A specific probe was designed to identify part of the genetic sequence of the ctxB gene which encodes for the B subunit of the cholera toxin by polymerase chain reaction (PCR) which amplifies a 318 bp segment of the ctxB gene. Marked with P32, we used this probe for colony hybridization which is a technique for identifying the production capacity of subunit B of strains of Vibrio cholerae O1 from different outbreaks in South America (Perú 1992 and Ecuador 1993-1995) and from, collection strains. This probe was tested for the identification of the ctxB gene in Vibrio cholerae O139. METHOD: Thirty-eight phylogenetically related strains were studied: 24 V. cholerae O1, 4 V. cholerae non O1, 5 Aeromonas, 4 Plesiomonas and 1 Escherichia coli. RESULTS: The probe demonstrated to be useful for the identification of the ctxB gene (which codifies for the subunit B of the cholera toxin) in 24 strains of Vibrio cholerae O1 and in the Vibrio cholerae O139 strain. The ctxB gene was not detected in the remaining strains pertaining to the Vibrio cholerae non O1 species (non O139), Plesiomonas, Aeromonas spp. and E. coli. The specificity of this product was not demonstrated since no signal of unspecific hybridization appeared with phylogenetically related strains such as Escherichia coli K88 (LT+) and Aeromonas hydrophila ATCC (LT+), producers of the thermolabile LT toxin. It is important to indicate that the ctxB gene in V. cholerae O139 has been identified, for the first time, with our probe and thus it may be said that all the strains which have genetic codification for CT up to now may be identified. CONCLUSIONS: We conclude that the system herein described provides advantages over the immunologic and biologic methods for evaluating a large number of samples in a short time and with excellent specificity and sensitivity which are important in the diagnosis and the epidemiologic surveillance of the disease.

Aeromonas↗
PubMed1995

mRNA retroposition in human cells: processed pseudogene formation.

Using a sensitive assay for detection of reverse transcription events, we demonstrate that human HeLa cells can 'retropose', i.e. reverse transcribe and integrate, the mRNA of a naive reporter gene, at a low but detectable frequency. Furthermore, we show that the retroposed copies have all the hallmarks of the processed pseudogenes naturally found in the mammalian genome: they lack intron and 5' promoter sequence, they have acquired a 3' poly(A) tail, and they are flanked by short repeats (< 15 bp) of target DNA sequence. These results demonstrate that human cells possess an endogenous reverse transcription activity, which is not restricted to transcripts of transposable elements, and which is likely to be involved in the formation, still ongoing, of a large fraction of the eukaryotic genome.

Base Sequence↗
PubMed1994

A randomized trial comparing preoperative chemotherapy plus surgery with surgery alone in patients with non-small-cell lung cancer.

BACKGROUND: The efficacy of surgery for patients with non-small-cell lung cancer is limited, although recent studies suggest that preoperative chemotherapy may improve survival. We conducted a randomized trial to examine the possible benefit of preoperative chemotherapy and surgery for the treatment of patients with non-small-cell lung cancer. METHODS: We studied 60 patients (59 men and 1 woman) with stage IIIA non-small-cell lung cancer. The patients were randomly assigned to receive either surgery alone or three courses of chemotherapy (6 mg of mitomycin per square meter of body-surface area, 3 g of ifosfamide per square meter, and 50 mg of cisplatin per square meter) given intravenously at three-week intervals and followed by surgery. All patients received mediastinal radiation after surgery. The resected tumors were evaluated by means of K-ras oncogene analysis and flow cytometry. RESULTS: The median period of survival was 26 months in the patients treated with chemotherapy plus surgery, as compared with 8 months in the patients treated with surgery alone (P < 0.001); the median period of disease-free survival was 20 months in the former group, as compared with 5 months in the latter (P < 0.001). The rate of recurrence was 56 percent in the group treated with chemotherapy plus surgery and 74 percent in the group treated with surgery alone. The prevalence of mutated K-ras oncogenes was 15 percent among the patients receiving preoperative chemotherapy and 42 percent among those treated with surgery alone (P = 0.05). Most of the patients treated with chemotherapy plus surgery had tumors that consisted of diploid cells, whereas the patients treated with surgery alone had tumors with aneuploid cells. CONCLUSIONS: Preoperative chemotherapy increases the median survival in patients with non-small-cell lung cancer.

Adult↗
PubMed1994

A randomized trial of mitomycin/ifosfamide/cisplatin preoperative chemotherapy plus surgery versus surgery alone in stage IIIA non-small cell lung cancer.

The efficacy of surgery or radiotherapy as conventional treatment for stage IIIA non-small cell lung cancer (NSCLC) is limited. Recent studies have pointed out that preoperative chemotherapy may improve survival. To reconcile the two approaches, we undertook a multidisciplinary randomized trial to examine the possible synergism between preoperative chemotherapy and surgery in improved survival. Stage IIIA NSCLC patients were randomly assigned to receive either three preoperative courses of mitomycin/ifosfamide/cisplatin chemotherapy and surgery or surgery alone. The median survival was significantly greater in the chemotherapy plus surgery group than in the surgery group (26 months v 8 months; P < .001). However, the prognostic value of the mutated K-ras gene data presented awaits the analysis of larger sample populations. Similarly, the role of high-dose cisplatin in inducing higher pathologic complete remissions has to be corroborated in future randomized trials.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Prognostic impact of mutated K-ras gene in surgically resected non-small cell lung cancer patients.

Mutated K-ras oncogenes have been detected in a third of lung adenocarcinomas, located usually in codon 12, its presence correlating negatively with survival. To further define the role of K-ras point mutations in non-small cell lung cancer, we studied the presence of mutated K-ras genes in surgical specimens from 66 patients. Polymerase chain reaction was performed from sections of formalin-fixed paraffin-embedded tissue. We screened for point mutations in codons 12, 13 and 61 of the K-ras gene by dot blot hybridization analysis with mutation-specific oligonucleotide probes. Ras gene mutations were present in 13 of 66 carcinomas (20%), nine in codon 12 and four in codon 61. Three squamous cell carcinomas harbored two different point mutations in K-ras codon 12. Mutated K-ras genes were found more frequently in squamous cell carcinomas (eight of 38) than in adenocarcinoma (three of 22). Analysis of nucleotide sequence disclosed a multifarious mutation pattern of K-ras codon 12, where the most common conversion was from glycine (GGT) to valine (GTT). K-ras point mutation positive subset had poorer survival, nine of the 13 patients died during the follow-up period as compared with 22 of 53 patients with no mutation in the K-ras gene (P = 0.01). The difference was also strikingly significant when stratified according to node status.

Adult↗
PubMed1991

Pulmonary mass and air meniscus sign in a 19-year-old man.

Sacrococcygeal teratoma is rarely diagnosed in adults. Pulmonary mass as the presenting clinical form of the malignant variety of this germ-cell tumor is exceptional. We report herein such a case with the noticeable peculiarity of showing the air meniscus sign on chest roentgenographic examination.

Adult↗