GCN2 phosphorylates HIV-1 integrase and decreases HIV-1 replication by limiting viral integration.

GCN2 is a serine/threonine kinase involved in cellular stress response related to amino acid starvation. Previously, we showed that GCN2 interacts with HIV-1 integrase and is activated during HIV-1 infection. Herein, we identified HIV-1 integrase as a previously unknown substrate of GCN2 in vitro with a major site of phosphorylation at residue S255 located in the C-terminal domain of HIV-1 integrase. The underlying mechanism was investigated and it appeared that the integrase active site was required in order for GCN2 to target the integrase residue S255. Moreover, various integrases from other retroviruses (e.g. MLV, ASV) were also recognized as a substrate by GCN2. In cells, HIV-1 lentiviral particles harboring mutation at integrase position 255 were affected in their replication. Preventing phosphorylation resulted in an increase in infectivity that correlated with an increase in viral DNA integration. Infectivity of MLV was also higher in cells knocked-out for GCN2 suggesting a conserved mechanism to control viral replication. Altogether, our data suggest that GCN2 may constitute a general guardian of genome stability by regulating foreign DNA integration and as such be part of the antiviral armamentarium of the cell.

Prevalence of HIV-1 drug resistance in treated patients with viral load >50 copies/mL: a 2014 French nationwide study.

Background: Surveillance of HIV-1 resistance in treated patients with a detectable viral load (VL) is important to monitor, in order to assess the risk of spread of resistant viruses and to determine the proportion of patients who need new antiretroviral drugs with minimal cross-resistance. Methods: The HIV-1 protease and reverse transcriptase (RT) and integrase genes were sequenced in plasma samples from 782 consecutive patients on failing antiretroviral regimens, seen in 37 specialized centres in 2014. The genotyping results were interpreted using the ANRS v24 algorithm. Prevalence rates were compared with those obtained during a similar survey conducted in 2009. Results: The protease and RT sequences were obtained in 566 patients, and the integrase sequence in 382 patients. Sequencing was successful in 60%, 78%, 78% and 87% of patients with VLs of 51-200, 201-500, 501-1000 and >1000 copies/mL, respectively. Resistance to at least one antiretroviral drug was detected in 56.3% of samples. Respectively, 3.9%, 8.7%, 1.5% and 3.4% of patients harboured viruses that were resistant to any NRTI, NNRTI, PI and integrase inhibitor (INI). Resistance rates were lower in 2014 than in 2009. Resistance was detected in 48.5% of samples from patients with a VL between 51 and 200 copies/mL. Conclusion: In France in 2014, 90.0% of patients in AIDS care centres were receiving antiretroviral drugs and 12.0% of them had VLs >50 copies/mL. Therefore, this study suggests that 6.7% of treated patients in France might transmit resistant strains. Resistance testing may be warranted in all treated patients with VL > 50 copies/mL.

HIV-1 dynamics and coreceptor usage in Maraviroc-treated patients with ongoing replication.

There is evidence that HIV-1 evolution under maraviroc (MVC) pressure can lead to the selection of either X4-tropic variants and/or R5-tropic, MVC-resistant isolates. However, the viral dynamics of HIV-1 variants in patients with virological failure (VF) on MVC-containing regimens remain poorly studied. Here, we investigated the V3 loop evolution of HIV-1 on MVC in relation to coreceptor usage and the nature of HIV-1 quasispecies before MVC therapy using bulk population sequences and ultradeep sequencing. The majority of patients had no detectable minority X4 variant at baseline. The evolution of tropism was followed up until VF and showed three possibilities for viral evolution in these patients: emergence of preexisting X4 variants, de novo selection of R5 variants presenting V3 loop mutations, or replication of R5 variants without selection of known mutations.

HIV-1 reverse transcriptase (RT) genotypic patterns and treatment characteristics associated with the K65R RT mutation.

BACKGROUND: The K65R HIV-1 reverse transcriptase (RT) mutation is a multidrug resistance mutation which may be correlated with specific antiretroviral combinations and with the presence or absence of other RT resistance mutations. OBJECTIVES: The aims of this study were: (i) to determine the prevalence of the K65R mutation in a cohort of antiretroviral-treated patients; (ii) to study genotypic patterns and treatment characteristics in patients in whom the K65R mutation was present. STUDY DESIGN: We included in the study all antiretroviral-experienced patients followed up at the Bordeaux University Hospital in 2003 and 2004 for whom an HIV-1 genotypic resistance analysis was available. Information on RT resistance mutations was reported from a hospital database including therapeutic and biological parameters. The prevalence of K65R was investigated for all patients. Genotypic patterns and treatment characteristics were examined at the time of detection of the K65R mutation. RESULTS: The prevalence of K65R was 1.9% (26 of 1404 patients). K65R was associated with nucleoside RT inhibitor-based regimens in 22 patients, and with tenofovir disoproxil fumarate, lamivudine, didanosine and abacavir in 23, 17, 17 and eight patients, respectively. The M184V and Q151M mutations were the most commonly co-selected substitutions. Thymidine analogue mutations (TAMs) were rarely co-selected with K65R and inversely associated with K65R. CONCLUSION: The K65R mutation may emerge preferentially in the absence of zidovudine and TAMs, suggesting the possibility of an antagonistic interaction between K65 and TAMs.

[Myositis as a 'radiation-recall phenomenon' following palliative chemotherapy with carboplatin-gemcitabin for non-small-cell pulmonary carcinoma]. / Myositis als 'radiatie-recallfenomeen' na palliatieve chemotherapie met carboplatine-gemcitabine voor niet-kleincellig longcarcinoom.

A 58-year-old woman suffered pain due to a stage-IV adenocarcinoma of the right upper-lung lobe with signs of growth into the right axilla. Palliative local radiotherapy directed at the primary tumour followed by combination chemotherapy with carboplatin-gemcitabin led to partial remission. During the fourth and last cycle of her three-months course of chemotherapy, the patient again complained of pain in the right half of the thorax; later, a local swelling of the pectoralis muscles was found. She was diagnosed with myositis as a delayed reaction to irradiation (radiation-recall phenomenon) based on the clinical symptoms (redness of the skin, pain and distinct swelling) but especially on the basis of a CT-scan. This revealed a clear swelling of the pectoralis muscles, even though the tumour was in remission. The possibility of myositis as a radiation-recall phenomenon should be borne in mind whenever a patient presents with skin changes or pain within a previous irradiation field during chemotherapy with, for example, gemcitabin.

Synthesis and characterization of fluorescent cobalamin (CobalaFluor) derivatives for imaging.

Fluorescent derivatives of cobalamin have been prepared by linking fluorophores to cobalamin through a propylamide spacer. Fluorescein, naphthofluorescein, and Oregon Green derivatives have been prepared in good yield by reaction of the fluorophore NHS-ester with beta-(3-aminopropyl)cobalamin to form fluorescent cobalamin conjugates (CobalaFluors) that are potentially suitable for the in vitro and in vivo imaging of transcobalamin receptors on cancer cells.

The value of lung function measurements for the assessment of chemotherapy in lung cancer patients.

A retrospective analysis of lung function changes in lung cancer patients (NSCLC and SCLC) receiving various chemotherapy regimens, showed--statistically non significant--improvements of some parameters in responders, especially FEV1 and VC (mean increase of 230 and 310 ml after three cycles of chemotherapy), while stable values were observed in non responders. The majority of patients suffered from a decline in diffusing capacity, irrespective of response. Although the specificity and sensitivity of this functional evaluation are too low to allow lung function parameters to replace more conventional staging procedures, improvement in lung function in responders might indicate that chemotherapy can improve quality of life.

Serum neuron-specific enolase as a tumor marker in the diagnosis and follow-up of small-cell lung cancer.

Serum samples for the determination of neuron-specific enolase (NSE) levels were collected at diagnosis, after induction of chemotherapy and at relapse in order to assess the value of NSE in the diagnosis and management of small-cell lung cancer (SCLC). At diagnosis, 47 of 64 patients with SCLC (73%) had abnormal NSE values (i.e. NSE > 12.5 micrograms/l). Mean NSE values were significantly higher in patients with extensive disease compared to limited disease. Patients with other malignancies or benign lung diseases presented with elevated NSE levels in approximately 15 and 4% of cases. Sensitivity, specificity and predictive value of positive results of NSE at diagnosis were 74, 83 and 71%, respectively, for a cutoff value of 12.5 micrograms/l. In responders mean NSE dropped significantly from 46.1 micrograms/l before chemotherapy to 17.0 micrograms/l after three cycles of chemotherapy. Nonresponders as a group showed a nonsignificant drop. At relapse mean NSE increased from 6.5 micrograms/l at the time of response to 51.9 micrograms/l at the time of progression, but in 5 of the 18 evaluable patients normal levels persisted. Thus, evolution of NSE in patients receiving chemotherapy correlated well with tumor volume in patients who responded, but often failed to predict a therapeutic outcome in patients with apparently chemoresistant tumor (i.e. some nonresponders showed a decrease in NSE levels). A similar lack of correlation between NSE levels and tumor volume was seen at the time of relapse. We conclude that the determination of NSE levels is of doubtful utility in the diagnosis and follow-up of SCLC patients.

Second primary lung cancer in Flanders: frequency, clinical presentation, treatment and prognosis.

Patient and tumour characteristics of 23 patients presenting with a second primary lung cancer were analysed and compared with 534 patients with radically resected stage 1 non-small cell lung cancer (NSCLC). None of these characteristics is associated with a higher occurrence rate for second primary lung cancer. Prognosis in the latter patients is significantly worse than after resection of a 'solitary' NSCLC: the median survival time (MST) after resection of the first tumour is 50 months; after diagnosis of the second tumour only 14 months. Surgically retreated patients have a prognosis that is similar to that after resection of a 'solitary' NSCLC. No separate independent prognostic factors responsible for this survival difference could be isolated. Squamous histology and central location are associated with a longer recurrence free survival time. We conclude that the occurrence of a second primary lung cancer can not be predicted based on patient or tumour characteristics and that only surgical retreatment offers a chance of long survival in these patients.

Paclitaxel for malignant pleural mesothelioma: a phase II study of the EORTC Lung Cancer Cooperative Group.

The EORTC Lung Cancer Cooperative Group undertook a phase II study of paclitaxel in 25 chemotherapy-naive patients with malignant pleural mesothelioma. Paclitaxel was given intravenously at a dose of 200 mg m-2 as a 3 h infusion every 3 weeks, after standard premedication with corticosteroids and antihistamines. This regimen was well tolerated, with < 4% of cycles resulting in severe toxicity. No major objective responses were observed and ten patients had stable disease. Median survival time was 39 weeks and the 1 year survival rate was 30%. In conclusion, paclitaxel at the dose and schedule investigated in this trial had no major activity in the treatment of malignant pleural mesothelioma.

Primary pulmonary Hodgkin's disease.

26 months after the onset of alcohol-induced pain, a diagnosis of primary pulmonary Hodgkin's (PPHD) disease could be made in a 34-year-old woman. Standard radiology of the thorax remains normal up to 18 months after the onset of symptoms. A short review of the literature concerning PPHD is given.

Fibrotic stage of allergic bronchopulmonary candidiasis.

Since its first description in 1952, ABPA has been recognized with increasing frequency. More recently fungi other than Aspergillus fumigatus, in particular Candida albicans, have been implicated in a similar disease process. The following case report illustrates the possibility of finding a fibrotic stage 5 ABPM caused by C albicans.

High Resolution Infrared Spectrometer in the 8-10-microm Range.

A double pass SISAM interferometer is presented. Its resolving power is close to 0.011 cm(-1) Accurate q(u) constants of 11(1)0 and 03(1)0 levels of N(2)O are calculated using the first spectra recorded.

Etalonnage absolu d'un spectrometre SISAM.

A SISAM spectrometer was adjusted. It was fitted with an apparatus for measuring absolute wavelengths. This used the fringes of a Fabry-Perot with emission lines. The results indicate that the width of the apparatus function is less than 0.025 cm(-1) and that the relative accuracy of the wavelength measurements is 0.003 cm(-1).