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NELL1 and NELL2 (neural epidermal growth factor-like 1 and 2) are recently described members of the epidermal growth factor gene family that have previously been shown to be expressed almost exclusively in brain tissue. Here we demonstrate regulated expression of NELL1 and NELL2 in human hematopoietic cells. Mature NELL1 mRNA is not detected in any normal hemopoietic cell type, although the gene is transcribed during a narrow window of pre-B cell development, and cell lines at the same developmental stage express the NELL1 mRNA. The related NELL2 gene is expressed by all nucleated peripheral blood cells examined (B, T, monocyte, and natural killer cells), but not in any of the bone marrow B lineage cells at earlier stages of development. However, leukemic cell lines corresponding to the same early differentiation stages express abundant NELL2 mRNA. These results suggest normal and possible oncogenic roles for the NELL proteins in hemopoietic cells. 相似文献
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Adoption programs can be enormously satisfying for all involved-not least the animals themselves-and constitute an important refinement in humane animal care and use. Most of the potential problems associated with adoption can be minimized with careful thought and planning. The authors describe adoption programs at two large academic campuses, noting differences between direct and indirect programs. 相似文献
95.
A new magnetic resonance imaging (MRI) contrast agent designed to mimic sialyl Lewis X (sLeX) and to target inflammation has been synthesized and characterized. The evolution of its proton longitudinal relaxivity as a function of the magnetic field (NMRD) and temperature has been studied. The exchange rate of the water coordinated to the metal has been assessed by oxygen-17 relaxometry. The transmetalation by zinc(II) ions and the noncovalent binding to human serum albumin have been evaluated. The results show no limitation by the residence time of the coordinated water molecule above room temperature, a higher stability of the complex versus transmetalation by zinc(II) ions than a parent complex, the clinically used Gd-DTPA-BMA, and negligible interaction with human serum albumin. 相似文献
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Sarah Hafsia Marion Haramboure David Arthur Wilkinson Thierry Baldet Luce Yemadje-Menudier Muriel Vincent Annelise Tran Clestine Atyame Patrick Mavingui 《PLoS neglected tropical diseases》2022,16(7)
BackgroundDengue is the world’s most prevalent mosquito-borne viral disease. It is endemic in many tropical and subtropical countries and represents a significant global health burden. The first reports of dengue virus (DENV) circulation in the South West Indian Ocean (SWIO) islands date back to the early 1940s; however, an increase in DENV circulation has been reported in the SWIO in recent years. The aim of this review is to trace the history of DENV in the SWIO islands using available records from the Comoros, Madagascar, Mauritius, Mayotte, Seychelles, and Reunion. We focus in particular on the most extensive data from Reunion Island, highlighting factors that may explain the observed increasing incidence, and the potential shift from one-off outbreaks to endemic dengue transmission.MethodsFollowing the PRISMA guidelines, the literature review focused queried different databases using the keywords “dengue” or “Aedes albopictus” combined with each of the following SWIO islands the Comoros, Madagascar, Mauritius, Mayotte, Seychelles, and Reunion. We also compiled case report data for dengue in Mayotte and Reunion in collaboration with the regional public health agencies in these French territories. References and data were discarded when original sources were not identified. We examined reports of climatic, anthropogenic, and mosquito-related factors that may influence the maintenance of dengue transmission independently of case importation linked to travel.Findings and conclusionsThe first report of dengue circulation in the SWIO was documented in 1943 in the Comoros. Then not until an outbreak in 1976 to 1977 that affected approximately 80% of the population of the Seychelles. DENV was also reported in 1977 to 1978 in Reunion with an estimate of nearly 30% of the population infected. In the following 40-year period, DENV circulation was qualified as interepidemic with sporadic cases. However, in recent years, the region has experienced uninterrupted DENV transmission at elevated incidence. Since 2017, Reunion witnessed the cocirculation of 3 serotypes (DENV-1, DENV-2 and DENV-3) and an increased number of cases with severe forms and deaths. Reinforced molecular and serological identification of DENV serotypes and genotypes circulating in the SWIO as well as vector control strategies is necessary to protect exposed human populations and limit the spread of dengue. 相似文献
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Angelo Peccerillo Giuliano F. Panza Abdelkrim Aoudia Maria Luce Frezzotti 《Rendiconti Lincei》2008,19(4):291-309
Shear-wave (V
S
) tomography along transects across the Western-Central Mediterranean area reveals heterogeneous lateral and vertical physical
characteristics in the lithosphere-asthenosphere system (LAS). A 50 km thick low velocity layer (LVL), with V
S
∼ 4.0–4.2 km/sec, typical of low rigidity fluid-bearing mantle material, is observed at a depth of about 70–120 km from offshore
Provence, to Sardinia and the Central Tyrrhenian Sea. This LVL, enclosed between higher velocity mantle rocks, rises to a
depth of less than 30 km below the recent and active volcanoes of Central Italy and the Southern Tyrrhenian Sea, where a maximum
in the heath flow is observed. The LVL is absent beneath Southeastern France and the northern border of the African foreland.
In the Balearic Sea-Sardinia-Central Tyrrhenian section, the depth of LVL corresponds to pressure conditions of minimum temperature
of peridotite+CO2+H2O solidus, consistent with conditions where fluid loss from the slab and mantle flow over the subducting plate favor significant
melt generation above steep, west-dipping subduction zones. It is suggested that LVL in the Balearic-Tyrrhenian domains is
the result of mantle contamination and melting left behind by the eastward retreating Adriatic-Ionian subducting plates from
Oligo-Miocene to present. This layer also marks a discontinuity between the lithospere and underlying mantle behind the subduction
zone, favoring detachment and westward drift of the lithosphere, and consequent opening of backarc basins.
These data support the hypothesis that the orogenic Oligocene to Quaternary volcanism in the Western Mediterranean area is
the effect of shallow mantle processes, and argue against the presence of deep mantle plumes. A shallow-mantle origin is also
suggested for the EM1-type Plio-Quaternary anorogenic magmatism in Sardinia and for the FOZO-DMM-type magmatism on the northern
margin of the African foreland.
相似文献
99.
Benziwa Nathalie Johnson Marie Luce Akossiwoa Quashie Gilles Chaix Letizia CamusKulandaivelu Kossi Adjonou Kossi Novinyo Segla Adzo Dzifa Kokutse Christine Ouinsavi Babou Andr Bationo Habou Rabiou Kouami Kokou Hlne Vignes 《Ecology and evolution》2020,10(23):13403
To study the genetic diversity and structure of the forest species Pterocarpus erinaceus Poir., seventeen polymorphic nuclear microsatellite markers were isolated and characterized, using next‐generation sequencing. Three hundred and sixty‐five (365) individuals were analyzed within fifteen (15) West African populations. The number of alleles for these loci varied from 4 to 30, and the heterozygosity varied from 0.23 to 0.82. The seventeen (17) primers designed here will allow characterizing the genetic diversity of this threaten species on its natural stands and to better understand the population differentiation mechanisms shaping it. 相似文献
100.