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The mosquito Aedes aegypti(L.) is the primary vector of various infectious viruses and is typified by a polymorphic color and abundance of white scales on the body. It has been conventionally separated into two subspecies, Ae. aeg. formosus(Walker) (Aaf) and Ae. aeg. aegypti(L.) (Aaa), with Aaf considered a ‘sylvan’ form and Aaa a ‘domestic’ form. Because the two subspecies show different susceptibilities to dengue viruses it is important to understand their distribution. In this study, we collected larvae from artificial and natural habitats in southern Kenya and reared them to adults to morphologically identify subspecies. We describe the geographical distribution and relative abundance of Aaa and Aaf in Kenya, and estimate the environmental factors associated with their distributions by GIS using climate and environment data. A total of 5,243 Ae. aegyptiadults were collected from 249 sites, with Aaa accounting for 22% of the specimens. The relative abundance of Aaa was higher in coastal areas versus sites in western Kenya. Aaa abundance was also higher in urbanized than forested areas, which is consistent with known ecology. In contrast and inconsistent with previous studies, both Aaa and Aaf were sympatric in artificial and natural habitats. The high relative abundance of Aaa in coastal areas might derive from old populated cities, climate, and/or introduction from abroad.

Abstract: A numerical model and computational procedure for static recrystallization are developed using a phase-field method coupled with crystal-plasticity theory. In this model, first, the microstructure and dislocation density during the deformation process of a polycrystalline metal are simulated using a finite element method based on strain-gradient crystal-plasticity theory. Second, the calculated data are mapped onto the regular grids used in the phase-field simulation. The stored energy is calculated from the dislocation density and is smoothed to avoid computational difficulty. Furthermore, the misorientation required for nucleation criteria is calculated at all grid points. Finally, phase-field simulation of the nucleation and growth of recrystallization is performed using the mapped data. By performing a series of numerical simulations based on the proposed numerical procedure, it has been confirmed that the recrystallization microstructure can be reproduced from the deformation microstructure.

Summary: A 7-year and 11 month-old girl with cerebellar astrocytoma linked to familial ataxia-telangiectasia (AT) is presented. She was born as the 7th girl of a woman with aortic arch syndrome. Two elder sisters of the patient have ataxia telangiectasia. She had immunodeficiency, and cerebellar ataxia, but had no oculocutaneous telangiectasia. The risk of cancer developing in AT patients is about 1,200 times greater than that in age-matched controls. With regard to central nervous system tumours, seven primary tumours have been reported, such as 3 cases of medulloblastoma and 4 cases of glioma. Members of AT families who were under the age of 45 had a risk of dying of a malignant neoplasm five times greater than in the general population. However, there were no reports of glioma in AT families. In this case, it is suggested that IgA deficiency linked to familial AT may have contributed to the development of astrocytoma.

125I-Hemoglobin.haptoglobin injected intravenously into rats was incorporated into liver parenchymal cells as evidenced by a cell separation technique. A mixture of freshly isolated liver parenchymal and nonparenchymal cells failed to internalize and degrade the 125I-hemoglobin.haptoglobin added, although it retained the ability to bind the molecule. The liver parenchymal cells in primary culture also lacked the ability to degrade 125I-hemoglobin.haptoglobin, although they bound the molecule more extensively as compared with the freshly isolated liver cells. It was confirmed that the 125I-hemoglobin.haptoglobin which was bound to the freshly isolated liver parenchymal cells localized on the outer surface of liver plasma membranes. Scatchard plots revealed the existence of two binding sites for 125I-hemoglobin-haptoglobin on the isolated liver plasma membrane: an apparent high affinity binding site (Kd = 1.3 X 10(-7) M) and an apparent low affinity binding site (Kd = 4.0 X 10(-6) M) at 37 degrees C. In contrast, freshly isolated liver parenchymal cells had only an apparent low affinity binding site (Kd = 1.4 X 10(-6) M) at 37 degrees C. Impairment of the apparent high affinity binding site during the isolation procedure with collagenase seemed to be related to loss of the ability to internalize and degrade the 125I-hemoglobin.haptoglobin molecules into the freshly isolated liver parenchymal cells or liver parenchymal cells in primary culture.

The binding of [ 125I]Hpx—heme with the rat hepatic plasma membrane receptor was studied at 37°C as well as different parameters such as plasma membrane concentration, calcium dependence, optimal pH and specific binding. A Scatchard plot revealed the existence of one binding for [ 125I]Hpx—heme on the isolated liver plasma membrane with a Kd= 3.2 × 10 −8M.

The binding of [125I]Hpx—heme with the rat hepatic plasma membrane receptor was studied at 37°C as well as different parameters such as plasma membrane concentration, calcium dependence, optimal pH and specific binding. A Scatchard plot revealed the existence of one binding for [125I]Hpx—heme on the isolated liver plasma membrane with a Kd= 3.2 × 10−8M.