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Biomedical subjects

M Antoine

Publications and source records attributed to M Antoine.

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

Sarcoid-like pulmonary disorder in human immunodeficiency virus-infected patients receiving antiretroviral therapy.

We report two cases of HIV-infected patients who presented with diffuse interstitial micronodular lesions on chest X-ray after institution of protease inhibitor-containing highly active antiretroviral therapy (HAART). Granulomatous pulmonary disorder mimicking sarcoidosis was diagnosed on histopathological studies revealing noncaseating granuloma and bronchoalveolar lavage analysis showing an intense CD4(+) lymphocyte alveolitis. Causative agents such as infectious organisms and environmental compounds were excluded. The relationship between sarcoid-like reaction and immune reconstitution under HAART is discussed.

Anti-HIV Agents↗
PubMed1999

Haemodynamic response to dynamic exercise after heart-lung transplantation.

The purpose of this study was to investigate the haemodynamic response to dynamic exercise after heart-lung transplantation (HLT). Nine stable HLT recipients (6 males) were studied 12-55 months after transplantation. While sitting on a cycle ergometer, they first underwent a maximal symptom-limited exercise test (power increment was 10 W x min(-1)) to determine the maximal tolerable workload. On the next day, they performed a second exercise test at 0, 40, 60 and 80% of their predetermined maximal workload (mean+/-sD: 108+/-20 W). Stage duration was 6 min. Respiratory, gas exchange, and haemodynamic measurements were performed at rest, during the last minute of each stage, and after recovery. Haemodynamic variables at rest were within normal limits except heart rate (HR) which was greater and stroke volume index (SVI) which was lower than normal. Peak oxygen consumption was 61+/-8% of predicted. HR showed an initial slow increase followed by a steeper rise, and a delayed return to baseline during the recovery period. SVI and cardiac index (CI) increased at the onset of exercise but did not change significantly at 40-80% of the maximal workload. Pulmonary capillary wedge pressure increased from 4+/-2 mmHg at rest to 14+/-3 mmHg at maximal exercise. It is concluded that during dynamic exercise, heart-lung transplantation recipients demonstrate a chronotropic incompetence, a reduced increase in cardiac index and stroke volume index, and an excessive rise in left ventricular filling pressures. These alterations may contribute to the persistent exercise limitation.

Adult↗
PubMed1999

[Small cell lung carcinoma].

Small cell lung carcinoma represents less than twenty five percent of all lung cancers. Nevertheless, a lot of studies permitted to better define this cancer and to propose specific therapeutic approaches. Clinical symptoms, results and roles of chemotherapy, radiation therapy and surgery are discussed in this review.

Antineoplastic Agents↗
PubMed1999

[Inflammatory and/or locally advanced breast cancers. Difficulty evaluating the response to initial chemotherapy].

At the Tenon Hospital (Paris), 48 inflammatory or locally advanced breast cancers were treated by neoadjuvant chemotherapy (three different protocols), followed by surgery (mastectomy or tumorectomy and axillary dissection). The histological data of the specimens are analyzed with regard to the clinical and radiologic evolution. Twenty complete clinical responses (41%), 22 partial clinical responses (45%), and no response in six cases (14%) were observed. Histology demonstrated residual tumors in 42 cases (87.5%), even in the case of complete clinical response (14 cases), without notable change of the grade (SBR). Lymph node clearance demonstrated positive nodes in 38 cases (79%). Despite its great agreement with clinical examination, mammography does not predict the existence of histological residual tumors after initial chemotherapy. Chemotherapy allowed local treatment, but can rarely sterilize the tumor completely.

Adult↗
PubMed1998

Functional characterization of transcriptional regulatory elements in the upstream region and intron 1 of the human S6 ribosomal protein gene.

Expression of housekeeping genes involves regulation at comparable levels in a wide spectrum of cells. To define the cis-regulatory elements in the human S6 ribosomal protein (rpS6) gene, we made a series of deletions of the upstream non-transcribed region, including or excluding exon 1 or intron 1 sequences. The mutated rpS6 gene regulatory regions were fused to the chloramphenicol acetyltransferase reporter gene and transfected into HeLa and COS-1 cells. The results have identified three parts of the rpS6 gene that are required for efficient and specific transcription. The core promoter includes only a 40 bp region upstream of the transcription start site and initiation region. Both upstream and intronic elements enhance transcription from the core promoter. Furthermore, mutation of the splice donor site of intron 1 almost completely abolished the enhancing activity of the intronic transcriptional modulator. We used gel retardation assays to identify sequence-specific binding sites in the upstream region and in the proximal half of intron 1. Both common and different nuclear factors that bind the rpS6 gene promoter were identified in extracts from HeLa and COS-1 cells, suggesting that different transcription factors may bind specifically to the same binding region and might be interchangeable in their function to ensure high-level expression of housekeeping genes independently of the cell type.

Animals↗
PubMed1998

Reactivation of hepatitis B after transplantation in patients with pre-existing anti-hepatitis B surface antigen antibodies: report on three cases and review of the literature.

BACKGROUND: Patients who have been exposed to the hepatitis B virus (HBV) and who were able to clear the hepatitis B surface antigen from the serum and to develop anti-hepatitis B surface antigen (anti-HBs) antibodies are not considered at risk for HBV reactivation after solid organ transplantation. METHODS AND RESULTS: We, however, observed three solid organ transplant recipients who demonstrated clinically significant HBV reactivation after transplantation. All patients presented normal liver enzymes and serological stigmates of healed HBV infection at the time of transplantation, as indicated by the absence of hepatitis B surface antigen and the presence of anti-HBs and anti-hepatitis B core antibodies in the serum. Patient 1, a renal transplant recipient, presented HBV reactivation 3 years after transplantation and developed chronic HBV hepatitis. Patient 2 developed HBV reactivation 7 months after a second cadaveric renal graft and died of cirrhosis four and a half years after transplantation. Patient 3, a heart-lung transplant recipient, developed HBV reactivation within months after transplantation, but died of unrelated causes. HBV reactivation in the presence of anti-HBs antibodies has been previously reported in other settings of immunosuppression, mainly in patients with acquired immunodeficiency syndrome and after bone marrow transplantation, and may lead to fatal liver disease. Data from our renal transplant recipients suggest that the incidence of HBV reactivation among patients with anti-HBs and anti-hepatitis B core antibodies is about 5%. CONCLUSIONS: Transplant physicians should be aware of the risk of HBV reactivation in patients presenting with healed HBV infection before transplantation.

Adult↗
PubMed1998

Gastric perforation due to mucormycosis after heart-lung and heart transplantation.

BACKGROUND: Gastrointestinal complications are a well-documented source of morbidity and mortality after heart and lung transplantation. METHODS: We report on two patients who presented with gastric perforation caused by mucormycosis during the first 2 months after heart-lung and heart transplantation. RESULTS: In the first patient, the clinical presentation was insidious and the diagnosis was made at an advanced stage of the disease. Despite surgery and aggressive antifungal treatment, the patient died. In the second patient, the diagnosis was made promptly, but despite antifungal treatment, he presented with gastric perforation within a week. CONCLUSIONS: These cases illustrate that fungal invasive disease may be a cause of early gastrointestinal perforation after solid organ transplantation.

Adult↗
PubMed1998

Envelope and long terminal repeat sequences of an infectious murine leukemia virus from a human SCLC cell line: implications for gene transfer.

Development of methods for gene transfer into specific cell types or tissues is important for experimental research as well as clinical therapeutical approaches. We report here the cloning and characterization of the envelope (env) gene and the U3 region of a retrovirus from an infected human Small Cell Lung Cancer (SCLC) cell line. The replication of this murine retrovirus is also fully supported by other lung cancer cell lines of different histological origin. We present evidence that a long terminal repeat (LTR)-beta-galactosidase (beta-Gal) reporter construct performed as well as an analogous cytomegalovirus (CMV) promoter beta-Gal construct in the human lung epithelial cell line A549 and in the human larynx carcinoma cell line HEp2.

Amino Acid Sequence↗
PubMed1998

AIDS-related primary pulmonary lymphoma.

We describe 12 cases of AIDS-related primary pulmonary lymphoma occurring between 1986 and 1996 in a large French cohort of HIV-infected patients. Diagnostic criteria were: (1) histologically proven lymphomatous pulmonary involvement; (2) absence of mediastinal and/or hilar adenopathy on chest radiography; (3) absence of extrathoracic lymphoma extension. All patients were severely immunodeficient at the time of diagnosis. All but one patient presented with B and/or nonspecific respiratory symptoms. Chest radiography showed one or more marginated nodule(s) or large mass. CT scan showed a cavitary lesion in five patients. No lymph node enlargement or specific pleural effusion was detected. Transthoracic needle biopsies were performed in 10 patients and avoided open-lung biopsy for the diagnosis of lymphoma in five patients. All but one of the primary pulmonary lymphoma were high-grade B-cell non-Hodgkin's lymphomas. Using antilatent membrane protein-1 antibodies and an Epstein-Barr-Virus-encoded RNA transcript-specific probe, latent EBV infection of tumor cells was demonstrated in every case. All but one of the patients received chemotherapy. The median survival time was 4 mo, and no patient was still alive at the cut-off date for this analysis. Progessive pulmonary lymphoma was the main cause of death, but infections were also frequent.

AIDS-Related Opportunistic Infections↗
PubMed1998

Neutrophil alveolitis in bronchioloalveolar carcinoma: induction by tumor-derived interleukin-8 and relation to clinical outcome.

Tumor infiltrate, predominantly constituted by lymphocytes, may represent an important prognostic factor in bronchioloalveolar carcinoma (BAC), in addition to tumor extension and histological type. In the present study, we determined the presence, the origin, and the prognostic importance of neutrophils that also participate in leukocyte infiltrates of BAC. Neutrophil alveolitis was determined immunohistochemically in both lung biopsies and bronchoalveolar lavage (BAL) fluid samples from 29 patients with histologically proved BAC. The local expression of interleukin (IL)-8 was determined by immunohistochemical and immunoenzymatic techniques. Neutrophil counts were analyzed in relation to the clinical outcome of patients by the Kaplan-Meier method and Cox's univariate and stepwise multivariate models. Lymphocytes and neutrophils dominated the inflammatory cell population in the lower respiratory tract of patients with BAC. Neutrophils were located mainly in the alveolar lumen and seldom in alveolar wall whereas lymphocytes were exclusively present in alveolar wall. A relationship was observed between the number of neutrophils and the level of IL-8 in BAL fluid suggesting the involvement of that chemokine in neutrophil recruitment. The tumor cells were the predominant cells that appeared to express IL-8 by immunolocalization. The presence of increased numbers of neutrophils was significantly associated with a poorer outcome in patients with BAC (P = 0.02). In a multivariate analysis, the neutrophil percentage in BAL fluid was an independent predictor of clinical outcome. The risk of death was increased substantially (rate ratio, 5.2; 95% confidence interval, 1.1 to 24.7) among patients with BAL neutrophil percentage of > or = 39% (median of the distribution) as compared with the others. In BAC, neutrophils accumulate in the alveolar lumen. Elaboration of IL-8 by tumor cells may be responsible for this event, which is associated with a significantly higher risk of death.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1998

Covalent sequestration of the nitrogen mustard mechlorethamine by metallothionein.

The research reported here demonstrates covalent binding to the metal-binding protein metallothionein (MT) by the therapeutic nitrogen mustard mechlorethamine. The most surprising aspect of this interaction is the selectivity of the alkylating agent for specific residues of MT. A combination of MS and proteolytic and enzymatic methods was used to deduce specific locations of mechlorethamine alkylation. These experiments indicated that alkylation occurs predominantly in the carboxyl domain of MT, with one molecule of mechlorethamine covalently cross-linking two cysteine residues. Electrospray MS revealed the retention of all seven metal ions in the cross-linked MT/mechlorethamine adducts, highlighting the uniqueness of this protein. Computerized docking experiments supported the hypothesis that selective binding precedes selective alkylation, and the structure of the drug indicates the minimal structural requirements for this binding. These results support the idea that MT overexpressed in tumor cells contributes to the inactivation of anticancer drugs.

Alkylating Agents↗
PubMed1998

[Cystic opacity of the posterior mediastinum].

A patient with atypical clinical signs had a thoracic schwannoma in the left paravertebral gutter. Rigorous analysis of the standard x-rays, computed tomography examination and magnetic resonance imaging gave the diagnosis and guided surgical resection. The pathology report confirmed the imaging findings.

Humans↗
PubMed1998

[Pulmonary crytosporidium in a patient with AIDS].

Compared to digestive disorders, respiratory disease linked to cryptosporidium has not been very well documented in AIDS. We report a case of a patient suffering from AIDS who presented with chronic bronchial symptoms which became more and more incapacitating. Different respiratory specimens (broncho-alveolar lavage, expectoration and bronchial biopsy) revealed the presence of cryptosporidium species. The patient died in a few weeks from respiratory insufficiency without the parasite being eradicated from the bronchi. Although the autopsy confirmed the presence of cryptosporidium species, it was difficult to confirm its responsibility due to the fact that other pathogens were present in the bronchial tree.

AIDS-Related Opportunistic Infections↗
PubMed1997

Fibroblast growth factor 3, a protein with dual subcellular localization, is targeted to the nucleus and nucleolus by the concerted action of two nuclear localization signals and a nucleolar retention signal.

The major isoform of fibroblast growth factor 3 (FGF3) is initiated from a CUG codon, and the resultant product is distributed to the nucleus/nucleolus and secretory pathway. This dual subcellular localization is achieved in part by the competing effects of two classical intracellular targeting signals located near the amino terminus. At the extreme amino terminus is a short stretch of 29 amino acids before a signal peptide necessary for translocation into the endoplasmic reticulum, which is next to an adjacent bipartite nuclear localization signal. The carboxyl-terminal region of FGF3 is also implicated in nuclear/nucleolar localization. We describe here the characterization of carboxyl-terminal signals by showing they are capable of directing a heterologous protein, beta-galactosidase, to the nucleus. Furthermore, appending both the amino- and carboxyl-terminal domains onto beta-galactosidase, reproduces the dual subcellular localization properties of FGF3. Nuclear uptake of FGF3 appears to be signal-mediated since it binds to karyopherin alpha, the nuclear localization signal binding subunit of a heterodimeric receptor of the nuclear import machinery. The import of FGF3 into the nucleus is energy-dependent, and the inhibition of this process has demonstrated the importance of the nucleolar retention signal in nucleoplasmic and nucleolar accumulation.

Amino Acid Sequence↗
PubMed1997

Structure and erythroid cell-restricted expression of a chicken cDNA encoding a novel zinc finger protein of the Cys + His class.

We report the cloning, sequence analysis and expression pattern of chGfi, a zinc finger protein (Zfp)-encoding cDNA that was isolated from a cDNA library constructed with RNA from avian erythroblastosis virus (AEV)-transformed primary chicken erythroblasts. The 1387-bp-long chGfi cDNA encodes a full-length 337-amino-acid (aa) protein that contains six zinc fingers (Zf) of the 2Cys + 2His class at its C-terminus. Immunoblotting experiments with extracts from bone marrow cells detected a 38-kDa protein that corresponds to the M(r) of 38,690 calculated for the protein deduced from chGfi. The chGfi protein is most homologous to the rat Gfi-1 showing a sequence similarity of 92% over the Zf region and only two exchanges within the N-terminal 19 aa that constitute the Gfi-1 repressor domain. Expression of chGfi is only detected in transformed primary erythroblasts, in erythroid cells of the primitive and definitive lineage and in bone marrow cells. chGfi activity does not vary significantly during differentiation of transformed primary erythroblasts of the definitive lineage. No chGfi expression is detected in cells of the myeloid and lymphoid lineages or in a total of nine different organs of adult origin. Our results indicate that chGfi expression is restricted to erythroid cells of the primitive and definitive lineage.

Amino Acid Sequence↗
PubMed1997

Lung rejection occurs in lung transplant recipients with blood chimerism.

BACKGROUND: It has been postulated that chimerism after transplantation might promote graft acceptance. In the present study, we prospectively assessed blood chimerism in 10 lung transplant recipients during the first posttransplant year and investigated whether chimerism was associated with an immunologically stable situation of the graft. METHODS: The recipients' peripheral blood mononuclear cells were obtained before transplantation and at various time points during the first postoperative year. Donor cells were detected using nested polymerase chain reaction amplification of a donor-specific HLA-DRB1 allele. Clinical graft acceptance was determined by the number of rejection episodes. RESULTS: The incidence of blood chimerism was high during the first 3 postoperative months and then decreased over time. All patients experienced at least one acute rejection episode, and three patients developed chronic rejection. CONCLUSION: We, thus, conclude that rejection of the lung allograft may occur in the presence of blood chimerism.

Adolescent↗
PubMed1997

Role of pulmonary function in the detection of allograft dysfunction after heart-lung transplantation.

BACKGROUND: Lung function is altered by infection and rejection in patients who undergo heart-lung transplantation. The sensitivity, specificity, and positive/negative predictive values (PPV and NPV) of lung function for the detection of allograft dysfunction in these patients were measured. METHODS: Thirty three patients who underwent heart-lung transplantation were followed for a mean period of 16.3 months. On 123 occasions functional measurements were obtained at the time a transbronchial biopsy specimen and/or bronchoalveolar lavage fluid was taken, which were used as gold standards. Optimal sensitivity (the value for which sensitivity equals specificity) was computed for each functional test from receiver-operator characteristic (ROC) curves. RESULTS: Acute rejection was present on 31 occasions and infection on 36 occasions; 56 samples were normal. Infection and rejection were accompanied by airflow obstruction, a rise in the slopes of the alveolar plateaus for nitrogen, hexafluoride sulphur and helium (SN2, SSF6, and SHe), and a decrease in the difference between SSF6 and SHe (delta S), total lung capacity (TLC), and lung transfer factor (TLCO). Optimal sensitivities for SHe, mid forced expiratory flow (FEF25-75), TLC, and forced expiratory volume in one second (FEV1) were 68%, 67%, 66%, and 60%, respectively; they were not different for infection and rejection and did not change over the study period. For infection and rejection together, PPV ranged from 72% to 88% and NPV from 27% to 52% according to the functional test and the postoperative period considered. CONCLUSIONS: Indices of ventilation distribution, FEF25-75, and TLC have the best optimal sensitivity for the diagnosis of infection and rejection after heart-lung transplantation. The high PPV of pulmonary function in detecting allograft dysfunction observed in this study suggests that a diagnostic procedure should be performed whenever one or more functional tests deteriorate; conversely, the low NPV indicates that a stable pulmonary function does not rule out allograft dysfunction.

Adolescent↗