The treatment of chronic myelogenous leukemia (CML) with imatinib mesylate (IM) has dramatically improved the prognosis of this disease, notably for chronic phase (CP) patients. However, a ...significant proportion of CP patients may progress along the years and it is important to identify early markers of poor response in order to offer to such patients the best alternative treatment. It has been demonstrated recently that the activity of some membrane transporters such as the organic cation transporter 1 (OCT-1), and ATP-binding cassette transporters (ABCB-1 and ABCG-2) may modify IM intracellular concentrations within leukemic cells and influence disease response and survival. In this study, we enrolled 76 CP CML patients (47M, 29F) at diagnosis and we measured in 66 patients on peripheral blood (PB) samples with RQ-PCR, the levels of OCT-1, ABCB-1 and ABCG-2 and analyse the impact on disease response and steady-state plasmatic IM and desmethyl-IM trough concentrations. The transporter data generated were normalised using a pool of peripheral blood samples from 10 healthy blood donors. Additionally, OCT-1 SNPs in exons 1 to 9 have been analysed in 41 patients out of 76. Median age at diagnosis was 50.3 (18.1–81.8) years, Sokal score was high for 16 (21%), intermediate for 34 (45%) and low for 23 (30%) patients and unknown for 3 (4%), Hasford score was high for 5 (7%), intermediate for 29 (38%), low for 30 (39%), and unknown 12 (16%). IM alone was initiated at 400 mg/day for 50 patients, 600 mg/day for 3 patients, IM was associated to monthly subcutaneous courses of 14 days Cytarabine in 13 patients and to Peg-IFN-a in 10 patients the first year of treatment. Heighty eight percent of patients were in optimal cytogenetic response (PCyR) at 6 months. Seven percent, 33%, 39%, 46%, 59% and 63% of patients were in major molecular response MMR, BCR-ABL/ABL (IS) <0.1% at 3, 6, 9, 12, 18 and 24 months respectively. Univariate analysis demonstrated a significant correlation (p=0.04) between ABCG-2 RQ-PCR levels at diagnosis and the proportion of patients in MMR at 6 months, between ABCB-1 levels and MMR at 12 months (p<0.01), and between OCT-1 levels and MMR at 24 months. A conditional logistic-regression model was used to analyse associations between molecular responses and transporter RQ-PCR levels, age, gender, Sokal and Hasford scores, and showed that only ABCB-1 levels were a favourable factor on the MMR rate at 12 months (HR= 2.62, 95%CI= 2.32–6.10). Logrank test did not find any significant impact of transporters levels, IM and desmethyl-IM trough concentrations, on disease progression. More extensive statistical analysis will be presented. OCT-1 SNPs analysis identified 3 patients with polymporphisms reported to decrease the enzymatic activity of OCT-1 (exon 1) and 1 patient with a polymorphism reported to fully abolish OCT-1 activity (exon 1). However, these 4 patients showed optimal cytogenetic and molecular responses, suggesting the involvement of other mechanisms in the regulation of the response to IM. Ten patients were identified with OCT-1 polymorphisms (in exons 2, 3 and 7) reported not to influence the enzymatic activity of this protein. In conclusion, the activity of these transporters (as assessed by RQ-PCR) may have some impact on the molecular response of CP CML to front-line IM therapy, however, the interrelationships between the different transporters in conjunction with other factors (drug-drug interactions, genetic background…) do not contribute to clearly distinguish one transporter more than another as a key prognostic factor for IM-molecular disease control.
In vitro Plasmodium falciparum drug sensitivity was investigated in 115 brazzavillians children, between 1 year and 10 years of age. On the basis of clinical aspects, four groups were constituted: ...Group 1: 39 asymptomatic school children, Group 2: 16 children with uncomplicated malaria, Group 3: 40 with severe but not pernicious malaria and Group 4: 20 with pernicious malaria. The drugs tested were chloroquine (CQ), quinine (QN) and mefloquine (MQ). The sensitivity level was assessed by a 48-hour in vitro maturation test involving the uptake of tritiated hypoxanthine, the initial blood level of parasite being > or = 0.1% in all cases. For QN and MQ, the median IC50 values showed no significant difference related to clinical status, age or parasitaemia levels. For CQ, the proportion of resistant strains and the 50 inhibitory concentration (IC50) values were greater in the cases of children hospitalised for malaria but there were no differences related to clinical severity of these hospitalised children nor, within each group, to the age or parasitaemia levels. The percentage of subjects with an IC50 value greater than the 90 percentile of the IC50 of the asymptomatic group, which we propose as the severity index related to chemoresistance, was 15% for uncomplicated malaria, 38% for severe but non-pernicious forms and 35% for pernicious malaria. The IC50 for QN was significantly higher in CQ-resistant strains and there was a positive correlation for CQ vs QN and for QN vs MQ.
The usefulness of a nested PCR assay for detection of Aspergillus sp. DNA was evaluated in 177 bronchoalveolar lavage (BAL) fluid specimens. This test was accurate both to diagnose culture-negative ...BAL fluid specimens from patients with invasive pulmonary aspergillosis and to confirm culture-positive samples. However, it did not differentiate between infection and colonization.
CLINICAL REPORT: A clinical report of a contact lenses wearer with Acanthamoeba keratitis pointed out the diagnosis problem. The medical treatment is needed previously to any surgery. Finally the ...patient underwent enucleation. DISCUSSION: The authors are considering the microbiological aspects and laboratory techniques are described. CONCLUSION: For this very severe but hopefully rare pathology, the sooner the treatment the best. A therapeutic approach is described.
The FLRG gene encodes a secreted glycoprotein that binds to activin and is highly homologous to follistatin, an activin ligand. We cloned the promoter region of the human FLRG gene, and defined the ...minimal region necessary for transcription activation in a reporter-system assay. We showed that the fragment between positions -130 and +6, which consists of multiple consensus Sp1-binding sites, is required for the constitutive expression of the FLRG gene. We demonstrate here that FLRG mRNA expression is rapidly induced by TGFbeta or by transfection with Smad protein expression vectors in human HepG2 cells. We investigated the transcription-regulation mechanism of FLRG expression in HepG2 cells following treatment with TGFbeta. By deletion and point-mutation analysis of the FLRG promoter, we identified a Smad-binding element involved in the TGFbeta-inducible expression of the FLRG gene. Moreover, transactivation of the FLRG promoter by TGFbeta was compromised by dominant-negative mutants of Smad3 and Smad4 proteins. In addition, gel electrophoresis mobility-shift assays demonstrated the specific interaction of Smad3 and Smad4 proteins with the Smad-binding element consensus motif found in the FLRG promoter. Taken together, our data imply that Smad proteins participate in the regulation of expression of FLRG, a new target of TGFbeta transcription activation.
Various projects were launched in 1993 to monitor the chemosensitivity of Plasmodium falciparum in Congo. Resistance of 34 strains in Brazzaville to chloroquine, quinine and mefloquine and of 35 to ...halofantrine was investigated in an in vitro survey using an isotopic micro test. The resistance rates were 61.8, 14.7, 3.0 and 0.0% respectively. Thus, the chemoresistance which first appeared in 1990 is confirmed and is stable in the population. This finding was further confirmed by a parallel in vitro analysis of sensitivity to chloroquine in Brazzaville. A chloroquine monitoring network is now being established throughout the country based on simplified WHO tests of 100 asymptomatic schoolchildren conducted every six months. The first results in 1993, from three Southern regions indicate that parasites are found in 20 to 60% of cases seven days after a standard 3 day treatment with 25 mg/kg, according to the region. The results of in vitro and in vivo tests are very variable. Indeed, the value of such results for these tests for national monitoring is questionable: a more reliable system of identifying true therapeutic failures would be better suited.
Afin de poursuivre la surveillance de la chimiosensibilité de Plasmodium falciparum au Congo, différentes actions ont été ccconduites en 1993. A Brazzaville une enquête in vitro utilisant un microtest isotopique a permis de tester 34 souches face à la choloroquine, la quinine et la méfloquine, et 35 face à l'halofantrine. Avec des taux de résistance à ces drogues de respectivement 61,8%, 14.7%, 3 et 0%, la stabilité de la chimiorésistance in vitro, entrevue en 1990, se confirme actuellement. Cette stabilité dans la capitale est également confirmée par l'étude de la chloroquinosensibilité in vivo menée parallèlement lors de cette enquête. Dans le reste du pays, un réseau de chloroquinosurveillance se met en place sous forme de tests OMS simplifiés réalisés chez 100 écoliers asymptomatiques tous les six mois. Les premiers résultats obtenus en 1993 dans trois régions du sud du pays montrent que, après un traitemetn standard de 25 mg/kg, pendant 3 jours, des parasites sont retrouvés à J7 dans 20 à 60% des cas selon les endroits. Par ailleurs les résultats des tests in vitro et in vivo réalisés sur les mêmes souches sont très différent entre eux. Cet élément conduit les auteurs à s'interroger sur la signification des résultats de tels tests dans le cadre d'une surveillance nationale. Le recours à un système fiable de détection des vrais échecs thérapeutiques semble plus adapté à cet objectif.
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