Search PubMed⌕ Search

Biomedical subjects

G Garnier

Publications and source records attributed to G Garnier.

At least 19 recordsLinked to original sources

A weekly schedule of docetaxel for metastatic hormone-refractory prostate cancer.

RATIONALE: Docetaxel has proven its efficacy in the management of hormone-refractory prostate cancer (HRPC). Schedules of docetaxel administration differ. This prospective phase II study was designed to reevaluate the activity and toxicity of docetaxel administered weekly at an optimal dose to a large cohort of HRPC patients. PATIENTS AND METHODS: Sixty-four patients were treated with docetaxel 40 mg/m(2) i.v., administered weekly for 6 consecutive weeks followed by a 2-week recovery period. Three treatment cycles were planned in the absence of progression or toxicity. The principal end point was the biochemical response based on the prostate-specific antigen (PSA) level (a decline of more than 50% for at least 4 weeks). Secondary end points were objective response to measurable disease, survival and toxicity. RESULTS: Toxicity was assessed in 64 patients. Toxicity was acceptable, with no toxicity-related deaths. Twenty-one percent of the patients developed grade 3-4 hematological toxicity. Sixty-four patients were evaluable for the PSA response. Forty-one patients (64%) achieved a decrease in PSA of >50%, 13 of whom had a PSA <4 ng/ml. Two out of 12 patients with measurable disease exhibited an objective response. With respect to PSA, the median progression-free survival was 29 weeks (95% confidence interval: 18-46 weeks). The global 1-year survival rate was 58%. CONCLUSION: Weekly docetaxel at a dosage of 40 mg/m(2) is a well-tolerated treatment, which has very promising activity on the reduction of PSA in metastatic HRPC. A large phase III study is underway.

Aged↗

Complement component C3 is not required for full expression of immune complex glomerulonephritis in MRL/lpr mice.

Complement activation and tissue deposition of complement fragments occur during disease progression in lupus nephritis. Genetic deficiency of some complement components (e.g., Factor B) and infusion of complement inhibitors (e.g., Crry, anti-C5 Ab) protect against inflammatory renal disease. Paradoxically, genetic deficiencies of early components of the classical complement pathway (e.g., C1q, C4, and C2) are associated with an increased incidence of lupus in humans and lupus-like disease in murine knockout strains. Complement protein C3 is the converging point for activation of all three complement pathways and thus plays a critical role in biologic processes mediated by complement activation. To define the role of C3 in lupus nephritis, mice rendered C3 deficient by targeted deletion were backcrossed for eight generations to MRL/lpr mice, a mouse strain that spontaneously develops lupus-like disease. We derived homozygous knockout (C3(-/-)), heterozygous (C3(+/-)), and C3 wild-type (C3(+/+)) MRL/lpr mice. Serum levels of autoantibodies and circulating immune complexes were similar among the three groups. However, there was earlier and significantly greater albuminuria in the C3(-/-) mice compared with the other two groups. Glomerular IgG deposition was also significantly greater in the C3(-/-) mice than in the other two groups, although overall pathologic renal scores were similar. These results indicate that C3 and/or activation of C3 is not required for full expression of immune complex renal disease in MRL/lpr mice and may in fact play a beneficial role via clearance of immune complexes.

Albuminuria↗

Modulation of renal disease in MRL/lpr mice genetically deficient in the alternative complement pathway factor B.

In systemic lupus erythematosus, the renal deposition of complement-containing immune complexes initiates an inflammatory cascade resulting in glomerulonephritis. Activation of the classical complement pathway with deposition of C3 is pathogenic in lupus nephritis. Although the alternative complement pathway is activated in lupus nephritis, its role in disease pathogenesis is unknown. To determine the role of the alternative pathway in lupus nephritis, complement factor B-deficient mice were backcrossed to MRL/lpr mice. MRL/lpr mice develop a spontaneous lupus-like disease characterized by immune complex glomerulonephritis. We derived complement factor B wild-type (B+/+), homozygous knockout (B-/-), and heterozygous (B+/-) MRL/lpr mice. Compared with B+/- or B+/+ mice, MRL/lpr B-/- mice developed significantly less proteinuria, less glomerular IgG deposition, and decreased renal scores as well as lower IgG3 cryoglobulin production and vasculitis. Serum C3 levels were normal in the B-/- mice compared with significantly decreased levels in the other two groups. These results suggest that: 1) factor B plays an important role in the pathogenesis of glomerulonephritis and vasculitis in MRL/lpr mice; and 2) activation of the alternative pathway, either by the amplification loop or by IgA immune complexes, has a prominent effect on serum C3 levels in this lupus model.

Animals↗

Genetic disruption of the murine complement C3 promoter region generates deficient mice with extrahepatic expression of C3 mRNA.

Genetic deficiencies of the complement protein C3 occur naturally in humans and animal models and have been induced in mice by targeted deletion of the C3 gene. The study of these deficiencies has provided evidence for C3 functions in immune responses. C3 deficient mice were generated by replacing the 5'-flanking region of the C3 gene with the neomycin-resistance (neo) gene. Serum from these mice had no detectable C3 protein or complement activity. Challenge with Streptococcus pneumoniae revealed approximately 2000-fold increase in bacteremia as compared to littermate controls. C3 mRNA was absent in the liver, but it was detected in the lung, kidney, fat tissue, heart and spleen. Metabolic labeling of the lung tissue and peritoneal macrophages showed synthesis of pro-C3, but no post-synthetic intracellular processing of the protein and no secretion of mature C3. cDNA analysis at the cap site indicated that extrahepatic transcription of the targeted gene was initiated in the neo cassette, close to the C3/neo junction and predicted a primary translation product lacking the leader peptide. The data indicate that these mice provide a good animal model for the study of complete C3 deficiencies and a potential probe for tissue-specific C3 gene regulatory elements.

Animals↗

Identification of a novel alternatively spliced mRNA of murine pulmonary surfactant protein B.

An alternatively spliced mRNA of pulmonary surfactant protein B (SP-B) was identified in murine lung. Sequencing analysis revealed a 69 base-pair (bp) deletion at the beginning of exon 7 of SP-B, presumably the result of an alternative splicing event. Reverse transcription-polymerase chain reaction (RT-PCR) of mouse, rat, and rabbit lung RNA revealed the existence of full-length and the 69-bp deleted short form. Ribonuclease protection assay of the SP-B messenger RNA (mRNA) demonstrated expression of both isoforms in five strains of adult and fetal mice with different genetic backgrounds, as well as in rabbit, but not in human. Splice junction sequences in exon 6 and at the exon 7 splice boundary for the two isoforms are similar, including AG doublet identity, but sequence differences do not account for species variation in isoform abundance. The abundance of the short SP-B mRNA isoform was approximately 30% of total SP-B mRNA in mouse and rabbit. Analysis of precursor SP-B protein in mouse lung suggested that the two mRNA species are expressed as stable protein isoforms.

Alternative Splicing↗

Long-term survivors of small-cell lung cancer (SCLC): a French multicenter study. Groupe d'Oncologie de Langue Française.

BACKGROUND: The aim of this study was to analyze SCLC patients beyond 30 months, particularly their outcome, their way of life, and factors which could influence relapses, second-primary cancers and death. PATIENTS AND METHODS: Between January 1986 and May 1995, 263 SCLC patients who survived longer than 30 months were included from 52 French institutions. The analysis was performed on the 155 cases confirmed by a pathologic review. RESULTS: Physical, mental and psychological states were considered as normal at 30 months in respectively 70.3%, 87.7% and 67.7% of patients, not influenced by prophylactic cranial irradiation, number of chemotherapy cycles, CCNU or cisplatin. Therapeutic sequelae were neurological impairment (13%), pulmonary fibrosis (18%) and cardiac disorders (11%) at 30 months. Return to work was possible for 40% of patients in the first two years following diagnosis. Among 43 relapsing patients, 33 benefited from a second-line treatment. Their median survival was 12 months since retreatment, and seven patients have survived again longer than 30 months. Age > 60 at the time of diagnosis was found as an independent factor increasing the risk of relapse beyond 30 months (OR = 2.46, IC 95% (1.16-5.26), P = 0.01). The risk of relapse became less than 10% beyond five years. Twenty patients (13%) developed a second primary cancer in a mean time of 58.6 months. The risk of second primary cancer was increased by a number of chemotherapy cycles > 6 (OR = 3.25, IC 95% (1.08-9.8) P = 0.02) and by an age > 60 (OR = 2.92, IC 95% (1.07-7.97), P = 0.03). Five- and 10-year survival rates were respectively 68% and 44%. In these patients having reached a 30-month survival, three independent factors were predictive of a survival longer than five years: age < or = 60 at the time of diagnosis (OR = 2.85, IC 95% (1.23-6.6), P = 0.01), chest radiotherapy (OR = 3.1, IC 95% (1.28-7.69), P = 0.006) and absence of relapse (OR = 4.5, IC 95% (1.75-12.5), P = 0.002). This study suggests that: 1) therapeutic sequelae are rather mild, allowing return to work in 40% of patients; 2) relapsing 30-month survivors can benefit from second-line treatment; 3) SCLC cure can be achieved with a 10-year follow-up.

Adult↗

Two cases of localized B-cell lymphoma in the acquired immunodeficiency syndrome.

We report 2 cases of localized B-cell non-Hodgkin lymphoma occurring on the face in AIDS patients. The tumors were limited to the skin and bone, without other involvement. They were characterized by an aggressive local behavior that caused infectious and compressive complications and resulted in fatal outcome. Knowledge of the possibility that lymphoma may remain localized in AIDS patients should prompt clinicians to perform a biopsy as soon as possible, regardless of the CD4 count. Indeed, early diagnosis might increase the efficacity of treatment and might avoid disastrous local complications.

AIDS-Related Opportunistic Infections↗

[Is fetal fibronectin a valid test predictive of premature labor?].

This study sought to determine the value of oncofetal fibronectin as predictor of preterm delivery in patients presenting with preterm labor. Patients admitted for preterm labor with intact membrane between 24 and 34 weeks gestation were included. A dacron swab applied to the external os for 10 seconds. The fetal fibronectin is detected bill a biologic membrane test. 90 patients were included. 25 (28%) had positive fetal fibronectin, and 13 (52%) had preterm delivery (specificity and positive value 81% and 52% respectively). Among 65 (72%) with negative fetal fibronectin, only 12 (18%) had preterm delivery (sensitivity 81% and negative predictive value 81%: p < 0.001). Median interval between sampling and delivery was 5 days in the positive compared to 23 in the false negative group. The presence of fetal fibronectin in the cervico-vaginal mucus strongly suggest an eminent delivery within few days after sampling. The sensitivity of the test is the 62% and still more interesting the negative predictive value is 86% (p < 0.001). The fetal fibronectin is a useful test to help the obstetrician discriminating true from false labor in patients with high risk preterm delivery. A negative test is very reassuring according to its high negative predictive value. Allowing to avoid unuseful tocolyse and long hospital.

Adult↗

Constitutive expression of murine complement factor B gene is regulated by the interaction of its upstream promoter with hepatocyte nuclear factor 4.

Factor B (Bf) is a constituent of the alternative pathway of complement activation encoded within the major histocompatibility complex. Transcription of the murine gene from two initiation sites generates two Bf mRNA species differing in size and tissue distribution. Striking genetic, tissue-specific differences in Bf mRNA levels at extrahepatic sites (kidney and intestine) among mouse strains correlate with a DNA sequence polymorphism in the 5'-flanking region of the gene and differential nuclear protein binding at the Bf upstream transcriptional initiation site (UIS). To ascertain the functional consequences of this polymorphism in the Bf promoter, we analyzed the effects of strain-specific sequences in the Bf 5' region on the expression of a chloramphenicol acetyltransferase (CAT) reporter gene transfected in human and mouse hepatoma cells. The CAT activity and mRNA level produced when transcription was driven by the sequence of strains with high extrahepatic expression were reduced to background levels when the sequence specific to the low expressor strains was used. Eighty percent of this difference was accounted for by a point substitution that affects DNA-protein interaction at the UIS, the sequence of higher affinity conferring higher expression. Hepatocyte nuclear factor 4 (HNF-4), derived from HepG2, mouse liver and kidney or cell-free translation of HNF-4 RNA, is the nuclear protein that preferentially binds to the high expressor UIS. Bf-CAT is not expressed in cells that lack HNF-4 (CV-1). However, co-transfection of HNF-4 into CV-1 cells drives Bf-CAT expression and reproduces the differences derived from the substitution that affect HNF-4 binding in vitro. These data show that interaction of HNF-4 with polymorphic variants of the upstream Bf promoter is the major determinant of strain-specific extrahepatic factor B expression.

Animals↗

[Hemostasis anomalies and human immunodeficiency virus infection].

Because hemostasis disorder in HIV infected patients are frequent and have clinical effects, they have aroused the interest of internal medicine. Such anomalies are not yet clearly defined and include various parameters. Thrombocytopenia which is the most widespread and the best documented manifestation, whether of peripheral origin by immunological platelet destruction or of central origin by a shortage in platelet production, responds well to medical treatment, especially to zidovudine. The circulating anti-coagulants frequently observed in HIV infected patients, whether anti-phospholipid antibodies or anti-cardiolipines are mostly asymptomatic. Other coagulation disorders (affection of the inhibitory system or fibrinolysis) are rarely observed and generally have no clinical incidence. Apart from thrombocytopenias and thrombotic thrombocytopenic purpura the incidence of clinical signs (thrombotic or hemorrhagic accidents) in HIV infected patients is not higher than in an HIV-free population and respond to the same treatment.

Blood Coagulation Disorders↗

Phase II study of alternating doses of vinorelbine in combination with cisplatin for non-small cell lung cancer (NSCLC): a disappointing experience.

UNLABELLED: In both Phase III trials of vinorelbine-cisplatin (VP) versus single-agent vinorelbine, the received vinorelbine dose intensities were 18.8 and 21.1 mg/m2 per week in the VP arms. Vinorelbine was administered at the weekly dose of 30 mg/m2. A new structure of the vinorelbine-cisplatin regimen delivering alternating doses of vinorelbine (35 mg/m2 on weeks 1, 3, 5 and 17.5 mg/m2 on weeks 2 and 4) was reported to increase the vinorelbine dose intensity in patients with non-small cell lung cancer (NSCLC). To further analyze the ability of such an alternating vinorelbine schedule to enhance vinorelbine delivery, a Phase II study of VP was conducted in NSCLC patients using the previously published alternating doses of vinorelbine for 6 cycles. Cisplatin was administered on weeks 1, 5 and every 6 weeks thereafter, at a dose of 75 mg/m2 in the first 14 patients and at a dose of 100 mg/m2 in the 18 remaining patients. The intended vinorelbine dose intensity was 26.25 mg/m2 per week. The median delivered dose intensities of vinorelbine calculated during the first 8-week period were: all patients, 17.9 mg/m2 per week; patients treated with cisplatin 75 mg/m2, 18.1 mg/m2 per week; patients receiving cisplatin 100 mg/m2, 17.9 mg/m2 per week; naive patients 18.2 mg/m2 per week and previously treated patients. 13.2 mg/m2 per week. Reductions and delays in the vinorelbine treatment mostly occurred on weeks 3 and 7, which are times of high-dose treatments (35 mg/m2) according to the protocol. The partial response rate was 34% (95% C.I. = 26-42%). Median survival was 21 weeks. The main toxicities were febrile neutropenia (nine patients, including two septic deaths) and constipation Grades 3 and 4 (five patients). CONCLUSION: The use of alternating doses of vinorelbine within the VP regimen did not lead to higher vinorelbine delivered dose intensities than those reported with a standard weekly 30 mg/m2 administration.

Adult↗

Translational regulation of murine complement factor B alternative transcripts by upstream AUG codons.

Factor B (Bf), a constituent of the alternative pathway of complement activation, is encoded by a single gene that is located within the MHC. In murine kidney and intestine, two Bf transcripts (Bf short and Bf long), generated from distinct transcriptional initiation sites, are expressed in approximately equal amounts. In the liver, > 95% of Bf mRNA is the short transcript. To ascertain the biologic consequences of this tissue-specific mRNA polymorphism, we quantitated the effect of structural differences between the two transcripts on net Bf protein synthesis. Cell-free translation of Bf mRNA in vitro revealed that the rate of translation of Bf short is about twice that of Bf long. The 5' extension of Bf long includes four short open reading frames upstream of the authentic translational initiation codons. Mutation of all four upstream AUGs generates a Bf long transcript with a translational rate about equal to that of Bf short. This effect was primarily accounted for by mutation of the second AUG from the 5' end. Similar studies of Bf expression in vivo showed an approximately twofold difference in translational rate between Bf long and the transcript mutated at the upstream AUGs. Because systemic and local inflammation in kidney alters the ratio of Bf long and short, net production of complement protein Bf in extrahepatic tissues is regulated by both transcriptional and translational control mechanisms.

Alternative Splicing↗

Subacute cutaneous lupus erythematosus associated with Hodgkin's disease.

Simultaneous occurrence of subacute cutaneous lupus erythematosus and malignancy has rarely been reported. We report the first case of subacute cutaneous lupus erythematosus associated with Hodgkin's disease. Although our case does not fulfill the criteria of paraneoplastic process, a relationship between the two disorders might be suggested by their simultaneous occurrence and in view of the cases of disseminated lupus erythematosus associated with lymphoma reported so far. The different hypotheses are discussed.

Hodgkin Disease↗

Phase I study of vinorelbine and carboplatin in advanced non-small cell lung cancer.

Thirty-one patients with previously untreated advanced non-small cell lung cancer were included in a Phase I study to determine the optimal dose of Carboplatin (CBDCA) which preserves the best Navelbine (NVB) dose-intensity. NVB was administered at a 30-mg/m2 fixed-dose on days 1-8/q 3 weeks, whereas CBDCA doses were planned to be escalated from 275 to 400 mg/m2 on day 1/q 3 weeks for six successive groups of patients. The toxicity limiting dose of CBDCA in the combination was 350 mg/m2 on day 1/q 3 weeks because of repetitive Grade IV neutropenia, and the optimal dose of CBDCA was 325 mg/m2 on day 1/q3 weeks, offering a 86.4% NVB and a 92.6% CBDCA relative dose-intensity for the first 9 weeks. Responses were observed at each step. This study demonstrates the feasibility and the efficacy of the NVB-CBDCA combination. It suggests that dose-intensity calculation can be helpful to determine the recommended dose for Phase II studies of new drug combinations.

Aged↗

Rearrangement of proximal 11q13 band in a CMML in acute transformation.

Fluorescence in situ hybridization (FISH) was performed on bone marrow cells thought to contain a t(7;11)(p22;q13) from a patient with chronic myelomonocytic leukemia in transformation. FISH analysis using a panel of 10 probes previously mapped to 11q13 revealed a cytogenetically undetected complex rearrangement that involved chromosomes 7 and 11 as well as a chromosome 3 at band p24. Two distinct translocation breakpoints, both proximal to the BCL1 locus, were found in chromosome 11 that perforce separate it into three subregions. The two breakpoints appear distinct from the two previously described ones which involved the FAU and GSTP1 genes. Our observations add to the involvement of proximal 11q13 in myeloid malignancies.

Acute Disease↗