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11.
Julielani T. Ngo Ivana Klisak Robert A. Dubin Joram Piatigorsky T. Mohandas Robert S. Sparkes J. Bronwyn Bateman 《Genomics》1989,5(4)
Using a human αB-crystallin genomic probe and human-mouse somatic cell hybrids, the human αB-gene was assigned to chromosome 11 and further corroborated by in situ hybridization to normal metaphase chromosomes. This assignment confirmed and regionally mapped the locus to q22.3–23.1. 相似文献
12.
F. Solimano G. I. Bischi M. Bianchi L. Rossi M. Magnani 《Bulletin of mathematical biology》1990,52(6):785-796
A non-linear three-compartment model is proposed to describe a new strategy for the administration of 2′,3′-dideoxycytidine
(ddCyd) in the treatment of HIV infections. The drug is injected after having been encapsulated in a non-diffusible form (ddCMP)
into erythrocytes. Nummerical solutions show that by this treatment the highest ddCyd blood concentration is strongly reduced
and in turn its toxicity, while long-lasting therapeutic effect is assured. The model is compared with experimental data in
vitro. 相似文献
13.
The decrease in the electron flow of the aerobic respiratory chain of the bacterium Paracoccus denitrificans, owing to either the drop in the saturation of terminal oxidases by oxygen or to the inhibition of the rate of respiration by azide or nitrite, resulted in the synthesis of dissimilatory nitrate reductase and nitrite reductase. The dependence of the resulting activities of the two enzymes (after a three-hour adaptation) on the initial value of the parameter Vmax/kLa (oxidase activity of the volume unit of the culture divided by the volumetric oxygen transfer coefficient) or on the concentrations of the inhibitors had a similar form, characterized by the appearance of a maximum. The increasing parts of the obtained curves reflect the synthesis of enzymes, probably initiated by the increase in the intracellular degree of reduction, the subsequent drop being evidently in connection with the lack of metabolic energy for biosynthesis. The possible mechanisms of the effect of nitrogenous terminal acceptors (NO-3 and NO-2) on the formation of the denitrification pathway are discussed. 相似文献
14.
Lydiya I. Sergeeva Ivana Macháčková Tatyana N. Konstantinova Svetlana A. Golyanovskaya Josef Eder Oksana O. Zaltsman Jan Hanuš Nina P. Aksenova 《Journal of Plant Growth Regulation》1994,13(3):147-152
The levels of endogenous IAA and cytokinins (zeatin, zeatin riboside, isopentenyladenine, and isopentenyladenosine) were determined in potato plants cultured in vitro under red light (R) and blue light (B) on medium with or without hormones. On medium without hormones in B, plants contained much higher cytokinin levels, particularly in leaves and roots, and also slightly elevated IAA levels. Kinetin in the medium in B changed the distribution of cytokinins and significantly increased IAA level in roots. In R, the presence of kinetin led to an increased cytokinin level in the whole plant, while the IAA level was slightly lower. IAA in the medium in B decreased cytokinin level in all plant parts, while the IAA level did not change significantly. In R, the presence of IAA in the medium led to a moderate increase of CK level and to a significant increase in IAA level, especially in roots. Uptake of 1-14C-IAA and of 3H-zeatin was generally higher in B than in R. Higher percentage of IAA taken up in B was converted to conjugates in the roots. Metabolism of 3H-zeatin was similar in R and B with only slight differences in metabolite amounts.Thus, in all experimental situations in which tuber formation was stimulated, IAA level in roots and stolons rose significantly, stressing the importance of an IAA gradient for tuber formation. 相似文献
15.
Magnani P. Paganelli G. Siccardi A. G. Songini C. Colombo P. Faglia G. Fazio F. 《Cell biochemistry and biophysics》1994,24(1-3):307-313
For various pituitary adenomas, it has been demonstrated that somatostatin receptor can be present. Pilot studies have shown
that radio-indium labeled pentetreotide allows very good scintigraphic localization of somatostatin receptor-bearing cell
masses. Recently, the presence of CgA in pituitary adenomas has also been demonstrated. MAb A11, raised against CgA, has been
successfully used with a three-step ISG for the diagnosis of neuroendocrine tumors. Therefore the combined use of three-step
ISG with MAb A11 and radiolabeled somatostatin can be useful in the diagnosis of pituitary adenomas. Twelve patients, 5 secreting
(group A) and 7 nonsecreting (group B) pituitary adenomas, were enrolled in the study. All patients underwent three-step ISG,
and, 2 wk later, scintigraphy with111In-labeled pentetreotide (Octreoscan). Three-step ISG consisted of iv injection of 1 mg of biotinylated MAb A11 (first step),
followed by 10 mg of avidin (second step) and [99mTc]PnAO-biotin (third step). Tomographic imaging were acquired for three-step ISG and Octreoscan at 2 and 4 h after radiotracer
injection, respectively. The results are the following: 2 patients of group A (secreting tumors) had a positive three-step
ISG, whereas all the patients but one of the same group had a positive pentetreotide study; all the patients of group B (nonsecreting
tumors) had a positive three-step ISG and 4 had a positive pentetreotide scintigraphy. These data suggest the utility of the
combined use of these techniques for a better diagnosis of pituitary adenomas. 相似文献
16.
Tupa Basuroy Megan Dreier Caitlin Baum Thomas Blomquist Robert Trumbly Fabian V. Filipp Ivana L. de la Serna 《Pigment cell & melanoma research》2023,36(1):19-32
Lineage-specific differentiation programs are activated by epigenetic changes in chromatin structure. Melanin-producing melanocytes maintain a gene expression program ensuring appropriate enzymatic conversion of metabolites into the pigment, melanin, and transfer to surrounding cells. During neuroectodermal development, SMARCA4 (BRG1), the catalytic subunit of SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodeling complexes, is essential for lineage specification. SMARCA4 is also required for development of multipotent neural crest precursors into melanoblasts, which differentiate into pigment-producing melanocytes. In addition to the catalytic domain, SMARCA4 and several SWI/SNF subunits contain bromodomains which are amenable to pharmacological inhibition. We investigated the effects of pharmacological inhibitors of SWI/SNF bromodomains on melanocyte differentiation. Strikingly, treatment of murine melanoblasts and human neonatal epidermal melanocytes with selected bromodomain inhibitors abrogated melanin synthesis and visible pigmentation. Using functional genomics, iBRD9, a small molecule selective for the bromodomain of BRD9 was found to repress pigmentation-specific gene expression. Depletion of BRD9 confirmed a requirement for expression of pigmentation genes in the differentiation program from melanoblasts into pigmented melanocytes and in melanoma cells. Chromatin immunoprecipitation assays showed that iBRD9 disrupts the occupancy of BRD9 and the catalytic subunit SMARCA4 at melanocyte-specific loci. These data indicate that BRD9 promotes melanocyte pigmentation whereas pharmacological inhibition of BRD9 is repressive. 相似文献
17.
Ivana Gribaudo M. Asuncion Morte Andrea Schubert 《Plant Cell, Tissue and Organ Culture》1995,42(3):303-303
Corrigendum
Use of gentian violet to differentiate in vitro and ex vitro- formed roots during acclimatization of grapevine 相似文献18.
Laura Chiarantini Luigia Rossi Alessandra Fraternale Mauro Magnani 《Molecular and cellular biochemistry》1995,144(1):53-59
Human and murine blood cells treated with ZnCl2 and bis(sulfosuccinimidyl)suberate (BS3) (a cross linking agent) undergo band 3 clustering and binding of hemoglobin to red blood cell membrane proteins. These clusters induce autologous IgG binding and complement fixation, thus favouring the phagocytosis of ZnCl2/BS3 treated cells by macrophages. The extension of red blood cell opsonization can be easily modulated by changing the ZnCl2 concentration in the 0.1–1.0 mM range thus providing an effective way to affect blood cell recognition by macrophages. In fact, murine erythrocytes treated with increasing ZnCl2 concentrations have proportionally reduced survivals when reinjected into the animal. Furthermore, the organ sequestration of ZnCl2/BS3 treated cells strongly resembles the typical distribution of the senescent cells. Since the ZnCl2/BS3 treatment can also be performed on red blood cells loaded with drugs or other substances, this procedure is an effective drug-targeting system to be used for the delivery of molecules to peritoneal, liver and spleen macrophages. 相似文献
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