Less effective selection leads to larger genomes

International audienceThe evolutionary origin of the striking genome size variations found in eukaryotes remains enigmatic. The effective size of populations, by controlling selection efficacy, is expected to be a key parameter underlying genome size evolution. However, this hypothesis has proved difficult to investigate using empirical datasets. Here, we tested this hypothesis using twenty-two de novo transcriptomes and low-coverage genomes of asellid isopods, which represent eleven independent habitat shifts from surface water to resource-poor groundwater. We show that these habitat shifts are associated with higher transcriptome-wide dN/dS. After ruling out the role of positive selection and pseudogenization, we show that these transcriptome-wide dN/dS increases are the consequence of a reduction in selection efficacy imposed by the smaller effective population size of subterranean species. This reduction is paralleled by an important increase in genome size (25% increase on average), an increase also confirmed in subterranean decapods and mollusks. We also control for an adaptive impact of genome size on life history traits but find no correlation between body size, or growth rate, and genome size. We show instead that the independent increases in genome size measured in subterranean isopods are the direct consequence of increasing invasion rates by repeated elements, which are less efficiently purged out by purifying selection. Contrary to selection efficacy, polymorphism is not correlated to genome size. We propose that recent demographic fluctuations and the difficulty to observe polymorphism variations in polymorphism-poor species can obfuscate the link between effective population size and genome size when polymorphism data is used alone

Suicide gene strategies applied in ovarian cancer studies

Ovarian cancer represents the most lethal gynecological malignancy among women in developed countries. Despite the recent innovations, the improvements in the 5-year survival rate have been insufficient and the management of this disease still remains a challenge. The fact that the majority of patients experience recurrent or resistant disease have substantiated the necessity of an innovative treatment. Among various strategies investigated, the recent strides made in gene delivery techniques have made gene therapy, including suicide gene strategies, a potential alternative for treating ovarian cancer. Various suicide gene candidates, which are capable of promoting cancer cell apoptosis directly after its entry or indirectly by prodrug administration, can be separated into three systems using enzyme-coding, toxin or pro-apoptotic genes. With this review, we aim to provide an overview of different suicide genes depending on therapeutic strategies, the vectors used to deliver these transgenes specifically to malignant cells, and the combined treatments of these genes with various therapeutic regimens

Warm brine lakes in craters of active mud volcanoes, Menes caldera off NW Egypt: evidence for deep-rooted thermogenic processes

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Repeated sustained release dinoprostone vaginal inserts in women with unfavorable cervix may increase the risk of postpartum hemorrhage: preliminary results

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The cytotoxic effect of combined hyperthermia and taxane chemotherapy on ovarian cancer cells: results of an in vitro study.

International audiencePURPOSE: Hyperthermic intraperitoneal chemotherapy (HIPEC) is under continuous evaluation as a potential treatment for ovarian cancer. The purpose of this study was to evaluate the effect of chemotherapy, drug concentration and temperature. MATERIALS AND METHODS: We examined the combined effects of hyperthermia and taxane chemotherapy on the clonogenic survival of the human ovarian carcinoma SHIN-3 cell line in vitro. RESULTS: When hyperthermia was combined with chemotherapy, the median lethal dose (LD50) was equivalent regardless of the duration of exposure, and was independent of the exposure temperature. Taxanes showed a similar LD50 over the temperature range tested. CONCLUSIONS: In our study, hyperthermia does not increase the cytotoxic effects of taxanes, at least for the concentrations and durations tested

Cytotoxic effect of hyperthermia and chemotherapy with platinum salt on ovarian cancer cells: results of an in vitro study.

International audiencePURPOSE: Hyperthermic intraperitoneal chemotherapy is continuously under evaluation in ovarian cancer. The purpose of the present study was to evaluate the effect of chemotherapy, drug concentration and temperature. MATERIALS AND METHODS: A human ovarian carcinoma cell line was used. The effect of hyperthermia combined with chemotherapy was analyzed. RESULTS: When hyperthermia was combined with chemotherapy, the 50% lethal dose (LD(50)) decreased with the duration of exposure. The effect of temperature was similar between 39 and 43 °C for a 30-min exposure. For a 60- to 90-min exposure, the LD(50) was equivalent between 38 and 43 °C. Beyond 40 °C, an increase in platinum salt concentration was necessary to obtain similar results according to the duration of exposure. CONCLUSIONS: The cytotoxic effect of the combination seemed to be potentiated and limited at 40 °C

Antenne compacte pour la détection de tumeurs cancéreuses du sein

National audienceAux fréquences basses du spectre microondes, les tumeurs cancéreuses du sein présentent des permittivités supérieures à celles des tissus constitutifs environnants. Cette caractéristique offre la possibilité de les détecter à partir d’antennes. La présence d’une tumeur se caractérise alors par un décalage fréquentiel du paramètre de réflexion S11. Nous présentons ici une antenne miniature à très faible bande passante pour des mesures en contact direct avec le sein. Une campagne de mesures a été menée sur plusieurs patientes, mettant en évidence la nécessité d’une modélisation très fine du sein ainsi que les limites de cette technique

Microstrip Back-Cavity Hilbert Fractal Antenna for Experimental Detection of Breast Tumors

International audienceThis paper presents a miniaturized microstrip back-cavity Hilbert Fractal Antenna specifically designed for breast cancer detection. This antenna is used to investigate on the possibility of detecting the presence of breast tumors by directly measuring the shift of the antenna resonance frequency. First, simulations are performed on a multi-layer breast model; then the proposed approach was applied for in vivo measurements on two different patients diagnosed with breast cancer, followed by ex vivo characterization of the electrical properties of excised tumors

Monte-Carlo dosimetry for intraoperative radiotherapy using a low energy x-ray source

International audienceIntraoperative radiotherapy (IORT) is continuously gaining ground in cancer treatment. However, there is currently no planning system associated with these devices, which precludes patient-specific dose delivery optimization. The objective of this study was the development and validation of a Monte Carlo simulation (MCS)-based dosimetry platform using the Intrabeam™ system