Selective expansion of viral variants following experimental transmission of a reconstituted feline immunodeficiency virus quasispecies

Following long-term infection with virus derived from the pathogenic GL8 molecular clone of feline immunodeficiency virus (FIV), a range of viral variants emerged with distinct modes of interaction with the viral receptors CD134 and CXCR4, and sensitivities to neutralizing antibodies. In order to assess whether this viral diversity would be maintained following subsequent transmission, a synthetic quasispecies was reconstituted comprising molecular clones bearing envs from six viral variants and its replicative capacity compared in vivo with a clonal preparation of the parent virus. Infection with either clonal (Group 1) or diverse (Group 2) challenge viruses, resulted in a reduction in CD4+ lymphocytes and an increase in CD8+ lymphocytes. Proviral loads were similar in both study groups, peaking by 10 weeks post-infection, a higher plateau (set-point) being achieved and maintained in study Group 1. Marked differences in the ability of individual viral variants to replicate were noted in Group 2; those most similar to GL8 achieved higher viral loads while variants such as the chimaeras bearing the B14 and B28 Envs grew less well. The defective replication of these variants was not due to suppression by the humoral immune response as virus neutralising antibodies were not elicited within the study period. Similarly, although potent cellular immune responses were detected against determinants in Env, no qualitative differences were revealed between animals infected with either the clonal or the diverse inocula. However, in vitro studies indicated that the reduced replicative capacity of variants B14 and B28 in vivo was associated with altered interactions between the viruses and the viral receptor and co-receptor. The data suggest that viral variants with GL8-like characteristics have an early, replicative advantage and should provide the focus for future vaccine development

Clinical relevance of KRAS mutation detection in metastatic colorectal cancer treated by Cetuximab plus chemotherapy

The predictive value of KRAS mutation in metastatic colorectal cancer (MCRC) patients treated with cetuximab plus chemotherapy has recently been suggested. In our study, 59 patients with a chemotherapy-refractory MCRC treated with cetuximab plus chemotherapy were included and clinical response was evaluated according to response evaluation criteria in solid tumours (RECIST). Tumours were screened for KRAS mutations using first direct sequencing, then two sensitive methods based on SNaPshot and PCR-ligase chain reaction (LCR) assays. Clinical response was evaluated according to gene mutations using the Fisher exact test. Times to progression (TTP) were calculated using the Kaplan–Meier method and compared with log-rank test. A KRAS mutation was detected in 22 out of 59 tumours and, in six cases, was missed by sequencing analysis but detected using the SNaPshot and PCR-LCR assays. Remarkably, no KRAS mutation was found in the 12 patients with clinical response. KRAS mutation was associated with disease progression (P=0.0005) and TTP was significantly decreased in mutated KRAS patients (3 vs 5.5 months, P=0.015). Our study confirms that KRAS mutation is highly predictive of a non-response to cetuximab plus chemotherapy in MCRC and highlights the need to use sensitive molecular methods, such as SNaPshot or PCR-LCR assays, to ensure an efficient mutation detection

Induction cisplatin–irinotecan followed by concurrent cisplatin–irinotecan and radiotherapy without surgery in oesophageal cancer: multicenter phase II FFCD trial

A recent phase I study showed that weekly cisplatin, irinotecan and concurrent radiotherapy can be administered with moderate toxicity in patients with oesophageal cancer. Patients with no prior treatment and oesophageal cancer stage I to III, performance status <3, caloric intake >1500 kcal day−1 were included. Chemotherapy, with cisplatin 30 mg m−2 and irinotecan 60 mg m−2, was administered at days 1, 8, 22, 29, and concurrently with radiotherapy at days 43, 50, 64 and 71. Radiotherapy was delivered with 50 or 50.4 Gy in 25 fractions/5 weeks. Forty-three patients were included, 10 stage I, 19 stage II and 14 stage III. Mean age was 59.2 years (range 44–79). A total of 30 out of 43 (69.8%) patients underwent all planned treatment. During induction chemotherapy, 14 severe toxicities of grade 3 or 4 in 10 patients (23.3%) were reported with 57.1% due to haematoxicity. During chemoradiotherapy, 31 severe toxicities of grade 3 or 4 with 64.5% due to haematotoxicity were reported in 18 patients. One toxic death occurred (diarrhoea grade 4). The complete clinical response rate was 58.1% (95% CI: 43.4–72.8%). Overall survival rate at 1 and 2 years was 62.8%, (95% CI, 58.3–77.3%) and 27.9% (95% CI, 13.4–41.3%), respectively. In conclusion, cisplatin–irinotecan–radiotherapy is an active and well-tolerated regimen feasible in out-patients

The Influence of Meteorology on the Spread of Influenza: Survival Analysis of an Equine Influenza (A/H3N8) Outbreak

The influences of relative humidity and ambient temperature on the transmission of influenza A viruses have recently been established under controlled laboratory conditions. The interplay of meteorological factors during an actual influenza epidemic is less clear, and research into the contribution of wind to epidemic spread is scarce. By applying geostatistics and survival analysis to data from a large outbreak of equine influenza (A/H3N8), we quantified the association between hazard of infection and air temperature, relative humidity, rainfall, and wind velocity, whilst controlling for premises-level covariates. The pattern of disease spread in space and time was described using extraction mapping and instantaneous hazard curves. Meteorological conditions at each premises location were estimated by kriging daily meteorological data and analysed as time-lagged time-varying predictors using generalised Cox regression. Meteorological covariates time-lagged by three days were strongly associated with hazard of influenza infection, corresponding closely with the incubation period of equine influenza. Hazard of equine influenza infection was higher when relative humidity was <60% and lowest on days when daily maximum air temperature was 20–25°C. Wind speeds >30 km hour−1 from the direction of nearby infected premises were associated with increased hazard of infection. Through combining detailed influenza outbreak and meteorological data, we provide empirical evidence for the underlying environmental mechanisms that influenced the local spread of an outbreak of influenza A. Our analysis supports, and extends, the findings of studies into influenza A transmission conducted under laboratory conditions. The relationships described are of direct importance for managing disease risk during influenza outbreaks in horses, and more generally, advance our understanding of the transmission of influenza A viruses under field conditions

Equine dendritic cells generated with horse serum have enhanced functionality in comparison to dendritic cells generated with fetal bovine serum

BACKGROUND: Dendritic cells are professional antigen-presenting cells that play an essential role in the initiation and modulation of T cell responses. They have been studied widely for their potential clinical applications, but for clinical use to be successful, alternatives to xenogeneic substances like fetal bovine serum (FBS) in cell culture need to be found. Protocols for the generation of dendritic cells ex vivo from monocytes are well established for several species, including horses. Currently, the gold standard protocol for generating dendritic cells from monocytes across various species relies upon a combination of GM-CSF and IL-4 added to cell culture medium which is supplemented with FBS. The aim of this study was to substitute FBS with heterologous horse serum. For this purpose, equine monocyte-derived dendritic cells (eqMoDC) were generated in the presence of horse serum or FBS and analysed for the effect on morphology, phenotype and immunological properties. Changes in the expression of phenotypic markers (CD14, CD86, CD206) were assessed during dendritic cell maturation by flow cytometry. To obtain a more complete picture of the eqMoDC differentiation and assess possible differences between FBS- and horse serum-driven cultures, a transcriptomic microarray analysis was performed. Lastly, immature eqMoDC were primed with a primary antigen (ovalbumin) or a recall antigen (tetanus toxoid) and, after maturation, were co-cultured with freshly isolated autologous CD5+ T lymphocytes to assess their T cell stimulatory capacity. RESULTS: The microarray analysis demonstrated that eqMoDC generated with horse serum were indistinguishable from those generated with FBS. However, eqMoDC incubated with horse serum-supplemented medium exhibited a more characteristic dendritic cell morphology during differentiation from monocytes. A significant increase in cell viability was also observed in eqMoDC cultured with horse serum. Furthermore, eqMoDC generated in the presence of horse serum were found to be superior in their functional T lymphocyte priming capacity and to elicit significantly less non-specific proliferation. CONCLUSIONS: EqMoDC generated with horse serum-supplemented medium showed improved morphological characteristics, higher cell viability and exhibited a more robust performance in the functional T cell assays. Therefore, horse serum was found to be superior to FBS for generating equine monocyte-derived dendritic cells

Traduction et validation française de l’échelle d’évaluation de la conscience des troubles mentaux des patients schizophrènes : The Scale to assess Unawareness of Mental Disorder (SUMD) [French translation and validation of the Scale to assess Unawareness of Mental Disorder (SUMD) in patients with schizophrenics].

International audienceThe Scale to assess Unawareness of Mental Disorder (SUMD) is a semi-structured interview based on a dimensional and quantitative approach of insight. Different forms of insight are assessed: global insight into mental illness, insight into symptoms and insight into symptom aetiology (i.e. attribution). The SUMD divides the recognition of mental disorders into two concepts: awareness of, and attribution for mental disorders. Awareness relates to the subject's ability to recognize that the phenomenon in question is present, whereas attribution refers to explanations as to cause or source of these signs or symptoms. Thus, the scale distinguishes between the recognition of a symptom and its explanation. For example, the scale allows the investigator to distinguish between a patient's ability to recognize visual hallucinations as such (false perceptions), from his/her ability to explain their cause (e.g. due to mental illness or not). The aim of this study was to translate the SUMD (version 3.1 revised) and test its convergent validity among 43 French adult inpatients diagnosed with schizophrenia according to DSM-IV-TR criteria. Awareness of mental disorder was assessed using the SUMD and the Hamilton Rating Scale for Depression (HAMD) insight item (item 17) respectively, as done in the original English validation study. The SUMD was translated into French then back-translated into English. The back-translation was performed by both English and French native speakers who had no prior knowledge of the scale (the back translation was reviewed by one of the SUMD's authors, Dr Amador, for accuracy). The SUMD manual (v.2/14/99) was also translated into French. Concerning the SUMD directions followed in this study, the first three SUMD items, which are called general items: G1 "Awareness of mental disorder", G2 "Awareness of the achieved effects of medication" and G3 "Awareness of the social consequences of mental disorder" were systematically rated. However, symptom items (four through 20) are not always relevant for every patient. Indeed, for each symptom-item on the scale, it must first be ascertained that the patient has exhibited the particular symptom during the period under investigation. Therefore, for every patient, the symptom checklist was completed prior to filling out the scale, in order to determine which symptom-items were relevant. In addition, symptom attribution items are rated only if the subject received a score between 1 and 3 on the awareness item. Two periods of time of insight were assessed: "current" insight involved rating the highest level of awareness obtained at the time of the interview for the psychopathology present at anytime during the past 7 days. "Past" insight was defined as the present level of awareness during the period of time preceding the current period of investigation. The French translation of the SUMD achieved good convergent validity with the insight item of the Hamilton rating scale for depression. The SUMD has proven to be a reliable and valid instrument to assess insight into schizophrenia. The more psychometrically sound rating tools we have at our disposal, many of which have been published in non French journals, the more we will be able to sharpen our assessment of insight into schizophrenia. We are facing an epistemic paradox in which quantification helps description, i.e. we need to have access to different rating tools to measure insight in order to improve our knowledge of the causes, course and treatment of poor insight into mental disorders

Medial unicompartimental knee arthroplasty for osteonecrosis or osteoarthritis

We report a prospective series of 33 unicompartmental knee arthroplasties (UKAs) operated for a spontaneous osteonecrosis of the knee (SPONK) compared with 35 UKAs operated for osteoarthritis (OA). The mean follow-up was 5 years. Preoperative functional score in the SPONK group was significantly lower than that in the OA group. The results were comparable in terms of pain, knee score and function. At the last follow-up, the survival rate was 92.8% for the SPONK group and 95.4% for the OA group. We found a higher rate of radiolucencies in the SPONK group, however, without any clinical symptoms. The UKA is a good option in the treatment of SPONK