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61.
Alain Chapel Sabine Francois Luc Douay Marc Benderitter Jan Voswinkel 《World journal of stem cells》2013,5(4):106-111
Radiotherapy may induce irreversible damage on healthy tissues surrounding the tumor. It has been reported that the majority of patients receiving pelvic radiation therapy show early or late tissue reactions of graded severity as radiotherapy affects not only the targeted tumor cells but also the surrounding healthy tissues. The late adverse effects of pelvic radiotherapy concern 5% to 10% of them, which could be life threatening. However, a clear medical consensus concerning the clinical management of such healthy tissue sequelae does not exist. Although no pharmacologic interventions have yet been proven to efficiently mitigate radiotherapy severe side effects, few preclinical researches show the potential of combined and sequential pharmacological treatments to prevent the onset of tissue damage. Our group has demonstrated in preclinical animal models that systemic mesenchymal stromal cell (MSC) injection is a promising approach for the medical management of gastrointestinal disorder after irradiation. We have shown that MSCs migrate to damaged tissues and restore gut functions after irradiation. We carefully studied side effects of stem cell injection for further application in patients. We have shown that clinical status of four patients suffering from severe pelvic side effects resulting from an over-dosage was improved following MSC injection in a compationnal situation. 相似文献
62.
Variants of the anti-Müllerian hormone gene in a compound heterozygote with the persistent Müllerian duct syndrome and his family 总被引:25,自引:0,他引:25
Danièle Carré-Eusèbe Sandrine Imbeaud Madeleine Harbison Maria I. New Nathalie Josso Jean-Yves Picard 《Human genetics》1992,89(4):389-394
Summary The human genome contains a large number of interspersed simple repeat sequences that are variable in length and can therefore serve as highly informative, polymorphic markers. Typing procedures include conventional multilocus and single locus probing, and polymerase chain reaction aided analysis. We have identified simple sequences in a cosmid clone stemming from the human Y chromosome and consisting of (gata)n repeats. We have compared these with two equivalent simple repeat loci from chromosome 12. After amplifying the tandemly repeated motifs, we detected between four and eight different alleles at each of the three loci. Codominant inheritance of the alleles was established in family studies and the informativity of the simple repeat loci was determined by typing unrelated individuals. The polymorphisms are suitable for application in linkage studies, practical forensic case work, deficiency cases in paternity determination, and for studying ethnological questions. The mutational mechanisms that bring about changes in simple repeats located both on the autosomes and on the sex chromosomes, are discussed.Professor Dr. Otto Prokop (Humboldt-Universität Berlin) on the occasion of his 70th birthday 相似文献
63.
64.
Sujoy Ghosh John W. Kyle Sara Dastgheib Francois Daussin Zhixiong Li Subhash Basu 《Glycoconjugate journal》1995,12(6):838-847
A 1-3 galactosyltransferase (GalT-3; UDP-Gal; GM2 1-3galactosyltransferase) was purified over 5100-fold from 19-day-old embryonic chicken brain homogenate employing detergent solubilization, -lactalbumin Sepharose, Q-Sepharose, UDP-hexanolamine Sepharose, and GalNAc1-4Gal-Synsorb column chromatography. The purified enzyme was resolved into two bands on reducing gels with apparent molecular weights of 62 kDa and 65 kDa, respectively. GalT-3 activity was also localized in the same regions by activity gel analysis and sucrose-density gradient centrifugation of a detergent-solubilized extract of 19-day-old embryonic chicken brain. Purified GalT-3 exhibited apparentK
mS of 33 µm, 22 µm and 14.4mM with respect to the substrates GM2, UDP-galactose, and MnCl2, respectively. Substrate specificity studies with the purified enzyme and a variety of glycosphingolipids, glycoproteins, and synthetic substrates revealed that the enzyme was highly specific only for the glycosphingolipid acceptors, GM2 and GgOse3Cer (asialo-GM2). Ovine-asialo-agalacto submaxillary mucin inhibited the transfer of galactose to GM2 but did not act as an acceptor in the range of concentrations tested. Polyclonal antibodies raised against purified GalT-3 inhibited GalT-3 activityin vitro and Western-immunoblot analysis of purified GalT-3 showed immunopositive bands at 62 and 65 kDa.Abbreviations CNS
central nervous system
- GM1
monosialotetraosylganglioside, Gal1-3GalNAc1-4(NeuAc2-3)Gal1-4Glc1-1Cer
- GM2
monosialotriaosylganglioside, GalNAc1-4(NeuAc2-3)Gal1-4Glc1-1Cer
- DSS
detergent solubilized supernatant
- ECB
embryonic chicken brain
- TBS
Tris-buffered saline 相似文献
65.
E. Kathryn Morris Francois Buscot Christine Herbst Torsten Meiners Elisabeth Obermaier Nicole W. Wäschke Tesfaye Wubet Matthias C. Rillig 《Biodiversity and Conservation》2013,22(10):2193-2205
Arbuscular mycorrhizal fungi (AMF) provide a number of ecosystem services as important members of the soil microbial community. Increasing evidence suggests AMF diversity is at least partially controlled by the identities of plants in the host plant neighborhood. However, much of this evidence comes from greenhouse studies or work in invaded systems dominated by single plant species, and has not been tested in species-rich grasslands. We worked in 67 grasslands spread across the three German Biodiversity Exploratories that are managed primarily as pastures and meadows, and collected data on AMF colonization, AMF richness, AMF community composition, plant diversity, and land use around focal Plantago lanceolata plants. We analyzed the data collected within each Exploratory (ALB Schwäbische Alb, HAI Hainich-Dün, SCH Schorfheide-Chorin) separately, and used variance partitioning to quantify the contribution of land use, host plant neighborhood, and spatial arrangement to the effect on AMF community composition. We performed canonical correspondence analysis to quantify the effect of each factor independently by removing the variation explained by the other factors. AMF colonization declined with increasing land use intensity (LUI) along with concurrent increases in non-AMF, suggesting that the ability of AMF to provide protection from pathogens declined under high LUI. In ALB and HAI mowing frequency and percent cover of additional P. lanceolata in the host plant neighborhood were important for AMF community composition. The similar proportional contribution of land use and host neighborhood to AMF community composition in a focal plant rhizosphere suggests that the diversity of this important group of soil microbes is similarly sensitive to changes at large and small scales. 相似文献
66.
The α-ASTREE e-Tongue instrument uses seven sensors to characterize taste signals associated with a liquid sample. The instrument was used to study eight test preparations (comprised of a blank, four preparations corresponding to four known tastes and Sodium Topiramate in three concentrations known to have a bitter taste) and eight washes. Serially balanced residual effects designs were used to order the samples to estimate residual and main effects. The design provided for eight repeated measurements per test preparation. The experimental results suggested the following: (1) The seven sensors can be separated into three groups according to the ability to discriminate test preparations, and three of the sensors contributed little or no information. Further investigation suggested the lack of differentiability might be due to the age of the sensors. (2) The sensors discriminated known tastes from blank. The residual effect due to test preparations might appear after repeated usage. (3) Exploratory principal component analysis of the data indicated that nearly 90% of the total variability across the seven sensors could be explained by a single principal component. (4) The four standard taste preparations did not correspond to orthogonal dimensions in the principal component axes. (5) The three Sodium Topiramate test preparations could neither be associated with the corresponding known bitter taste sample nor could the three doses be shown to follow a quantitative dose-response relationship on the e-Tongue measurement scale. The practical interpretation of the results of the statistical analysis indicates only poor discriminative ability of the e-Tongue to distinguish clearly between increasing concentrations of a known bitter compound such as Sodium Topiramate. No apparent linear relationship could be discerned over increasing concentrations that would allow the quantification of bitterness.KEY WORDS: cluster analysis, electronic tongue, principal component analysis, residual effects designs, serially balanced design 相似文献
67.
Marcus Eriksen Laurent C. M. Lebreton Henry S. Carson Martin Thiel Charles J. Moore Jose C. Borerro Francois Galgani Peter G. Ryan Julia Reisser 《PloS one》2014,9(12)
Plastic pollution is ubiquitous throughout the marine environment, yet estimates of the global abundance and weight of floating plastics have lacked data, particularly from the Southern Hemisphere and remote regions. Here we report an estimate of the total number of plastic particles and their weight floating in the world''s oceans from 24 expeditions (2007–2013) across all five sub-tropical gyres, costal Australia, Bay of Bengal and the Mediterranean Sea conducting surface net tows (N = 680) and visual survey transects of large plastic debris (N = 891). Using an oceanographic model of floating debris dispersal calibrated by our data, and correcting for wind-driven vertical mixing, we estimate a minimum of 5.25 trillion particles weighing 268,940 tons. When comparing between four size classes, two microplastic <4.75 mm and meso- and macroplastic >4.75 mm, a tremendous loss of microplastics is observed from the sea surface compared to expected rates of fragmentation, suggesting there are mechanisms at play that remove <4.75 mm plastic particles from the ocean surface. 相似文献
68.
Cady FM Muto DN Ciabeterri G Johns A Gainey Church K Wolff DJ 《Journal of the Association of Genetic Technologists》2004,30(3):77-81
Specific genetic abnormalities are of prognostic significance for patients with chronic lymphocytic leukemia (CLL) and multiple myeloma (MM); however, routine cytogenetic analysis usually provides normal results. We utilized two probe panels for interphase fluorescence in situ hybridization (FISH) studies to enhance the ability to detect genetic abnormalities in samples that were referred for routine cytogenetic studies for possible diagnoses of CLL or MM. The CLL panel consisted of probes for 11q22.3 (ATM gene), 13q14 (D13S319), the centromere of chromosome 12 (D12Z3) and 17p13.1 (P53 gene). The MM panel included probes for 14q32 (IgH gene) and/or t(11:14)(q13;q32) (BCL1/IgH), 13q14 (D13S319) and 17p13.1 (P53 gene). FISH detected clonal aberrations not identified by conventional cytogenetics in an additional 8 of 23 (35%) samples referred for possible CLL and 7 of 42 (17%) samples with possible MM. The prognostic significance of the aberrations identified ranged from favorable, to intermediate, to poor. Our studies indicate that many samples referred for routine cytogenetics testing for CLL and MM yield normal results for both conventional and FISH testing, likely due to lack of definitive diagnosis in a percentage of cases. However, FISH is more sensitive for the detection of clinically significant chromosome abnormalities and should be the testing methodology of choice for these disorders. 相似文献
69.
Pamela McElwee Katherine Calvin Donovan Campbell Francesco Cherubini Giacomo Grassi Vladimir Korotkov Anh Le Hoang Shuaib Lwasa Johnson Nkem Ephraim Nkonya Nobuko Saigusa Jean‐Francois Soussana Miguel Angel Taboada Frances Manning Dorothy Nampanzira Pete Smith 《Global Change Biology》2020,26(9):4691-4721
Interlocked challenges of climate change, biodiversity loss, and land degradation require transformative interventions in the land management and food production sectors to reduce carbon emissions, strengthen adaptive capacity, and increase food security. However, deciding which interventions to pursue and understanding their relative co‐benefits with and trade‐offs against different social and environmental goals have been difficult without comparisons across a range of possible actions. This study examined 40 different options, implemented through land management, value chains, or risk management, for their relative impacts across 18 Nature's Contributions to People (NCPs) and the 17 Sustainable Development Goals (SDGs). We find that a relatively small number of interventions show positive synergies with both SDGs and NCPs with no significant adverse trade‐offs; these include improved cropland management, improved grazing land management, improved livestock management, agroforestry, integrated water management, increased soil organic carbon content, reduced soil erosion, salinization, and compaction, fire management, reduced landslides and hazards, reduced pollution, reduced post‐harvest losses, improved energy use in food systems, and disaster risk management. Several interventions show potentially significant negative impacts on both SDGs and NCPs; these include bioenergy and bioenergy with carbon capture and storage, afforestation, and some risk sharing measures, like commercial crop insurance. Our results demonstrate that a better understanding of co‐benefits and trade‐offs of different policy approaches can help decision‐makers choose the more effective, or at the very minimum, more benign interventions for implementation. 相似文献
70.
Janine Duppach Sandra Francois Jara J. Joedicke Ulf Dittmer Anke R. M. Kraft 《Journal of virology》2014,88(23):13892-13896
It is still unclear whether expanded and activated regulatory T cells (Tregs) in chronic viral infections can influence primary immune responses against superinfections with unrelated viruses. Expanded Tregs found in the spleens of chronically Friend virus (FV)-infected mice decreased murine cytomegalovirus (mCMV)-specific CD8+ T cell responses during acute mCMV superinfection. This suppression of mCMV-specific T cell immunity was found only in organs with FV-induced Treg expansion. Surprisingly, acute mCMV infection itself did not expand or activate Tregs. 相似文献