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Urban sprawl and energy consumption issues suggest to consider how to design energy efficient dense cities. Solar radiation is a significant heat input in well insulated buildings in temperate climates. However, the solar masks generated by the surrounding buildings in dense urban areas can reduce significantly this energy gain. This paper proposes a definition of a district as a periodic urban fabric, where a given configuration of buildings, called urban cell , is repeated to represent the urban outline. It allows us to evaluate the relationship between cumulative solar potential on façades and urban shape, with solar masks that are consistent with the considered area. In this study, an evolutionary algorithm is used to explore the set of urban cells composed of a square grid of blocks of varying height. Four conditions for solar radiation are taken into account: clear sky direct radiation at the latitude of 50° North for three particular days (winter solstice, summer solstice and equinox), and annual direct and diffuse radiation based on the meteorological data of Paris, France. For each condition of solar radiation, the influence on the optimization results of the size of the area of interest and its built density is assessed. The results provide information on what are the urban shapes maximizing solar potential and give some quantitative indications on the amount of solar radiation that can be captured. [ABSTRACT FROM AUTHOR]

Deficiency of the urea cycle enzyme carbamylphosphate synthetase 1 ( CPS1) causes hyperammonemia with a vast range of clinical severity from neonatal onset with early lethality to onset after age 40 with rare episodes of hyperammonemic confusion. The cause for this variability is not understood. We report two patients from one family with highly divergent clinical course, one presenting neonatally with a fatal form and the other at age 45 with benign diet-responsive disease. The patients are compound heterozygous for two mutations of the CPS1 gene, c.3558 + 1G > C and c.4101 + 2T > C. The haplotypes containing each mutation are identical between the two patients, as are the sequences of CPS1 exons and flanking introns. Transcriptional experiments show that the abnormal CPS1 transcripts generated by both mutations are identical in these two patients. We characterize promoter and enhancer sequences of the CPS1 gene and find also in these regions no sequence differences between patients. Finally, we perform cloning experiments and find that in the neonatal-onset case, clones of messenger RNA (mRNA) expressed from the allele carrying the c.4101 + 2T > C mutation are threefold more than clones of mRNA from the allele with the c.3558 + 1G > C mutation, whereas in the adult-onset case the two types of clones are equal, indicating skewed expression towards the c.4101 + 2T > C allele in the neonatal case. Although we are yet to understand the mechanism of this differential expression, our work suggests that allelic imbalance may explain clinical variability in CPS1 deficiency in some families. [ABSTRACT FROM AUTHOR]

Abstract: Background. Glutamine synthetase (GS) is ubiquitously expressed in the human and plays a major role for many metabolic pathways. However, little is known about its role during the fetal period. Methods. Cultured skin fibroblasts derived from an aborted fetus deficient in GS activity due to a R324C exchange as well as fetal and mature controls were used to determine the level of GS-expression, apoptosis, and proliferation in presence or absence of exogenous glutamine. Results. Glutamine synthetase can be found at early gestational stages. Loss of GS activity either inherited or induced through l-methionine sulfoximine leads to an upregulation of the GS protein but not of the GS mRNA and results in a significant drop in the proliferation rate but has no effect on apoptosis. Exogenous glutamine does not influence the rate of apoptosis but increases proliferation rates of the fetal but not the mature fibroblasts. Conclusion. GS can be found during early human fetal stages when it displays a significant effect on cell proliferation. [Copyright &y& Elsevier]

Résumé: Les fistules coronaro-camérales sont des malformations souvent congénitales, rarement acquises ; la complication de cette anomalie d’un pseudo-anévrysme ventriculaire est exceptionnelle. Nous rapportons un nouveau cas de fistule coronaro-camérale acquise, survenue chez un patient ayant bénéficié d’un pontage aorto-coronaire et devenu symptomatique d’angor d’effort une année après la chirurgie. Sur le coroscanner, la fistule paraît communiquer la première diagonale à un pseudo-anévrysme du ventricule gauche. Une embolisation de la fistule et un comblement du pseudo-anévrysme par un neurocoil ont été réalisés avec succès. Le contrôle clinique et angiographique, réalisé après trois mois, a montré une disparition de la symptomatologie et l’absence de reperméabilisation de la fistule. [ABSTRACT FROM AUTHOR]

An abstract of the article "Apoptosis versus active gene transcription in skeletal muscle of chronic heart failure patients. The effect of exercise training," by V. Conraads and colleagues is presented.

An abstract of the study "Apoptosis Versus Active Gene Transcription in the Skeletal Muscle of Patients With Mild to Moderate Chronic Heart Failure. Relationship With Exercise Capacity," by V. Conraads and colleagues is presented.

Accurate quantification of the water balance, in particular evapotranspiration, is fundamental in managing water resources, especially in semi-arid areas. The objective of this study was to compare evaporation from endemic vegetation - Renosterveld - and a dryland wheat/fallow cropping system. The study was carried out in the mid-reaches of the Berg River catchment (South Africa), characterised by dryland salinity. Measurements of total evaporation from these 2 land uses were carried out with large aperture scintillometers during window periods from 2005 to 2007. Total evaporation was measured to be higher in Renosterveld than in wheat during the rainy winter season. In the dry summer season, total evaporation from Renosterveld was limited by soil water supply, and vegetation was under water stress. Spatial variability of total evaporation from both wheat/fallow land and Renosterveld was estimated using the Surface Energy Balance Algorithm for Land (SEBAL) model for 3 climatically different years. The scintillometer measurements were used to determine basal crop coefficients for long-term (20 years) simulations with the HYDRUS-1D model to assess temporal variability in total evaporation. Long-term simulations indicated that well-established, deep-rooted Renosterveld uses 39% more water than the shallowrooted wheat/fallow system. A change in land use from Renosterveld to dryland annual crops could therefore affect the soil water balance, cause shallow saline groundwater tables and degradation of soil and water resources. [ABSTRACT FROM AUTHOR]

Aims: Despite many improvements, cervical cancer screening is still subject to shortcomings. Diagnostic accuracy may improve by using molecular biological techniques, requiring RNA of superior quality. This study determined the effect of SurePath fixation on RNA integrity to assess the suitability of clinical samples collected in this medium for RNA-based molecular assays. Methods: RNA isolation was performed on fresh and fixed HeLa cells and exfoliated cervical cells fixed in SurePath. The RNA integrity was evaluated by analysis of ribosomal RNA as an indicator of quality. The effect of SurePath preservation on PCR amplification was evaluated by real-time reverse transcriptase (RT)-PCR. Results: In contrast to unfixed cells, SurePath-fixed cells yielded less and severely degraded RNA, as shown by the absence of ribosomal RNA bands. RNA derived from SurePath-fixed cells showed poor real-time RT-PCR amplification characteristics, as evidenced by the absent correlation between threshold values and log cDNA concentration. Conclusions: Implementation of molecular biology in a clinical context is on the rise and may alleviate shortcomings in current screening and diagnostics. This study shows that SurePath fixation gives rise to highly fragmented RNA with insufficient quality for further reliable analysis by standard real-time RT-PCR applications. The increasing prominence of molecular screening stresses the importance of this finding, which must be considered in relation to choice of an appropriate liquid-based cytology system. [ABSTRACT FROM AUTHOR]

Twenty isolates of Phytophthora infestans from potato and twenty-two from tomato, collected in Uganda and Kenya in 1995, were compared for dilocus allozyme genotype, mitochondrial DNA (mtDNA) haplotype, mating type and restriction fragment length polymorphism (RFLP) fingerprint using probe RG57. Based on RFLP fingerprint and mtDNA haplotype, all isolates were classified in the US-1 clonal lineage. Nonetheless, isolates from potato differed from isolates from tomato in several characteristics. Isolates from potato had the 86/100 glucose-6-phosphate isomerase (Gpi) genotype, while those from tomato were 100/100, which represents a variant of US-1 that had been identified previously as US-1.7. Furthermore, while pure cultures of the pathogen were acquired from infected potato leaflets by first growing the isolates on potato tuber slices, this approach failed with infected tomato tissue because the isolates grew poorly on this medium. Tomato isolates were eventually purified using a selective medium. Six isolates from each host were compared for the diameter of lesions they produced on three tomato and three potato cultivars in one or two detached-leaf assays (four isolates from the first test were repeated in the second). On potato leaflets, isolates from potato caused larger lesions than isolates from tomato. On tomato leaflets, isolates from that host caused larger lesions than did isolates from potato, but the difference was significant in only one test. The interaction between source of inoculum (potato or tomato) and inoculated host (potato or tomato) was significant in both tests. Isolates from tomato were highly biotrophic on tomato leaflets, producing little or no necrosis during the seven days following infection, even though abundant sporulation could be seen. In contrast, isolates from potato sporulated less abundantly on tomato leaflets and produced darkly pigmented lesions that were most visible on the adaxial side of the leaflets. Nonetheless, all isolates infected and sporulated on both hosts, indicating that host adaptation is not determined by an ability to cause disease but rather by quantitative differences in pathogenic fitness. Assessment of Gpi banding patterns, mtDNA haplotype and RFLP fingerprint of 39 isolates from potato collected in Uganda and Kenya in 1997 indicated that the population had not changed on this host. The population of P. infestans from Kenya and Uganda provides an interesting model for the study of quantitative host adaptation. [ABSTRACT FROM AUTHOR]

The article describes the cases of familial thoracic aortic aneyrysms /dissections (FTAAD) characterized by disease-causing heterozygous MYLK gene mutations. Member of the families were subjected to various medical procedures including screening of first-degree relatives, Petticoat examination at the aortic level, and thoracic endovascular aortic repair (TEVAR). Genetic mutations linked to aortic disease are described.