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21.
Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder that predisposes affected individuals to neoplasms of the parathyroid glands, endocrine pancreas, anterior pituitary, and carcinoids. The MEN1 locus has been localized by family studies to 11q13, flanked by markers PGA and D11S97. Eight new polymorphisms located in three separate radiation-reduced somatic cell hybrid segregation groups were developed. The order of the new markers, within the context of previously described loci, was determined by linkage analysis on the Venezuelan reference pedigree. Four independent MEN1 families, consisting of 57 affected individuals, and 70 individuals at-risk for the disease were genotyped. Sixteen people inherited a chromosome that shows recombination between a linked marker and the disease. The nearest proximal and distal markers that show recombination with the disease are D11S822 and GSTP1, respectively, thereby narrowing the candidate region for MEN1 by 50% on the distal side. Using these loci in haplotype analysis, an accurate presymptomatic molecular diagnostic test has been developed. These new markers in 11q13 linked to MEN1 also facilitate the genetic and physical characterization of this very gene-rich region. 相似文献
22.
Alessandra Cesano Sophie Visonneau Livia Cioé Steven C. Clark Daniela Santoli 《Cancer immunology, immunotherapy : CII》1995,40(3):139-151
The TALL-104 cell line, originally derived from a patient with T cell leukemia, can be maintained indefinitely in culture in the presence of interleukin-2 (IL-2) and is endowed with a highly potent major-histocompatibilitycomplex (MHC)-non-restricted tumoricidal activity both in vitro and in animal models. The present study analyzes in detail the short- and long-term effects of irradiation and cyclosporin A (CsA) treatment on the growth and tumoricidal function of this T cell clone as compared to polyclonal lymphokine-activated killer (LAK) cell preparations from healthy donors. DNA and RNA syntheses by both TALL-104 and LAK cells were irreversibly arrested a few hours after irradiation with 40 Gy. However, 4-h51Cr-release assays, performed on different days (day 1 to day 7) after irradiation, showed that the cytotoxic efficiency of TALL-104 cells against hematopoietic and solid tumor targets was only modestly reduced, whereas that of LAK cells was severely inhibited. Moreover, the cytotoxic responses to recombinant human IL-2 and IL-12, measured 18 h after irradiation and cytokine addition, were normal in the case of TALL-104 cells but were abolished in the case of LAK cells. Co-culture of IL-2-or IL-12-preactivated TALL-104 cells with a tumor target for 5 days in the absence of cytokines resulted in a lower efficiency of lysis, as compared to the non-irradiated effectors, especially if the initial stimulus was IL-12. These findings suggest the requirement of multiple cytokine stimulation for optimal expression of tumoricidal activity by lethally irradiated TALL-104 cells. CsA, while abrogating TALL-104 cell proliferation at the low dose of 0.5 g/ml, inhibited their cytotoxic function marginally only at high doses (100 g/ml). By contrast, CsA reduced dose-dependently the cytotoxicity of LAK cells starting at very low doses (0.5 g/ml). CsA did not impair the ability of TALL-104 and LAK cells to produce interferon (IFN), tumor necrosis factor (TNF) , and granulocyte/macrophage-colony-stimulatory factor (GM-CSF) in response to IL-2, IL-12, or tumor targets. Irradiation reduced drastically IFN production by LAK, but not TALL-104 cells; release of TNF and GM-CSF by either type of effector was inhibited by 10%–50%, depending on the stimulus. The high resistance of the TALL-104 cells' tumoricidal function to irradiation and immunosuppressive drugs renders this immortal T cell clone a potentially safe and effective reagent for new adoptive-transfer approaches to cancer in MHC-incompatible recipients. 相似文献
23.
Summary Conformational preferences of secretin as a model peptide have been analyzed by CD and IR spectroscopy in reverse micelles of AOT/isooctane/water and compared to those in aqueous TFE, in SDS micelles and in DMPG vesicles. Among the systems examined, reverse micelles and phospholipid vesicles displayed almost identical conformational equilibria. Very high lipid-to-peptide ratios can be obtained in reverse micelles with full retention of optical transparency, even at millimolar peptide concentrations, thus indicating this system to be an interesting mimic of cell membrane environments for spectroscopic analysis of bioactive peptide conformations.Abbreviations TFE
trifluoroethanol
- SDS
sodium dodecyl sulfate
- DMPG
dimyristoylphosphatidylglycerol
- AOT
bis(2-ethylhexyl)sulfosuccinate
- CMC
critical micellar concentration
- VIP
vasoactive intestinal peptide 相似文献
24.
The effect of high alkaline pH on the reinitiation of cell growth was studied in six different mammalian cells. We failed to confirm the observation of Zetterberg & Engström, Proc natl acad sci US 78 (1981) 4334 [17] and Exp cell res 144 (1983) 199 [18]. Treatment of quiescent cells at pH 9.5 did not stimulate cell growth when measured by total protein/flask or increase in cell number. 相似文献
25.
Daniela Duca Doina Ioan P. Meilă M. Ionescu-Cerna Ligia Simionescu C. Maximilian 《Human genetics》1981,57(2):214-216
Summary A dysmorphic 5-year-old girl with severe growth and mental deficiency was studied. She presented a de novo interstitial 2p deletion. Karyotype: 46,XX,del(2)(p13p15). 相似文献
26.
Arabidopsis thaliana tumors were induced by octopine strain ofAgrobacterium tumefaciens B6S3 and its derivatives with modified T-DNA. Flowering shoots appeared sponta-neously onin vitro cultivated tumors and set seeds. R1 and R2 progeny of octopine synthesizing plants segregated in opine synthesis activities 3:1 and 15:1. Octopine synthase activity
showed absolute linkage with agropine synthesis in most lines. In R3 and R4 progenies, the fraction of octopine synthase and agropine synthesis positive plants was lower than expected, but Mendelian
segregation was restored if plants were cultivated on medium with 5-azacytidine. The most probable mechanism of disapearance
of opine synthesis is cytosine methylation. The effect of 5-azacytidine lasted for at least next two generations. 相似文献
27.
28.
Remains of vertebrates of Villafranchian age have been found in the Nuraghe Su Casteddu (Nuoro, Sardinia) formation. The fossiliferous layer contain a rich fauna of continental molluscs. The composition of the vertebrate fauna is as follows: Rana sp., ? Coluber sp., Aves indet., Episoriculus aff. gibberodon PETENYI, Talpa sp., Chiroptera indet. and Rodentia indet. It is the first discovery of Villafranchian vetebrates in Sardinia. 相似文献
29.
Daniela Perrotta Enrique Frias-Martinez Ana Pastore y Piontti Qian Zhang Miguel Luengo-Oroz Daniela Paolotti Michele Tizzoni Alessandro Vespignani 《PLoS neglected tropical diseases》2022,16(7)
Timely, accurate, and comparative data on human mobility is of paramount importance for epidemic preparedness and response, but generally not available or easily accessible. Mobile phone metadata, typically in the form of Call Detail Records (CDRs), represents a powerful source of information on human movements at an unprecedented scale. In this work, we investigate the potential benefits of harnessing aggregated CDR-derived mobility to predict the 2015-2016 Zika virus (ZIKV) outbreak in Colombia, when compared to other traditional data sources. To simulate the spread of ZIKV at sub-national level in Colombia, we employ a stochastic metapopulation epidemic model for vector-borne diseases. Our model integrates detailed data on the key drivers of ZIKV spread, including the spatial heterogeneity of the mosquito abundance, and the exposure of the population to the virus due to environmental and socio-economic factors. Given the same modelling settings (i.e. initial conditions and epidemiological parameters), we perform in-silico simulations for each mobility network and assess their ability in reproducing the local outbreak as reported by the official surveillance data. We assess the performance of our epidemic modelling approach in capturing the ZIKV outbreak both nationally and sub-nationally. Our model estimates are strongly correlated with the surveillance data at the country level (Pearson’s r = 0.92 for the CDR-informed network). Moreover, we found strong performance of the model estimates generated by the CDR-informed mobility networks in reproducing the local outbreak observed at the sub-national level. Compared to the CDR-informed networks, the performance of the other mobility networks is either comparatively similar or substantially lower, with no added value in predicting the local epidemic. This suggests that mobile phone data captures a better picture of human mobility patterns. This work contributes to the ongoing discussion on the value of aggregated mobility estimates from CDRs data that, with appropriate data protection and privacy safeguards, can be used for social impact applications and humanitarian action. 相似文献
30.