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91.
Javier I. Escobar David J. Lakatua Barbara Streifel Norman L. Virnig Otto Sanchez 《Clinical genetics》1977,11(1):8-12
An abnormal chromosome No. 2 was found in the case of a child with an imperforate anus, a recto-vaginal fistula, unilateral atresia of the inner canal, and deformity of the external ear. G-banding studies revealed an insertion of a segment of the short arm into the long arm in one of the chromosomes No. 2 of the proband, the apparent result of a de novo phenomenon of chromosome rearrangement. 相似文献
92.
Miranda D Puente J Blanco L Jara P Wolf ME Mosnaim AD 《Research communications in molecular pathology and pharmacology》2002,111(1-4):3-12
Peripheral blood mononuclear cell (PBMC) cytotoxicity against S. typhi (wild type or mutant strain TYT1231)-infected U937 cells was significantly higher than its lytic effect against noninfected cells (control) at the various effector-to-target cell ratio used (30:1, 50:1 and 70:1). Natural killer cell activity [expressed as % specific lysis (mean +/- SEM); 30:1 (25.4 +/- 3.6, 25.1 +/- 4.2 and 16.3 +/- 3.3); 50:1 (27.8 +/- 3.7, 26.7 +/- 4.5 and 20.9 +/- 2.9) and 70:1 ratio (33.2 +/- 5.9, 29.4 +/- 4.2 and 22.8 +/- 2.8), respectively] appeared to be dependent on such ratios and independent of the S strain studied. Most (80%) of individual samples tested showed at least a 20% specific lysis increase over their own control; essentially no changes or smaller increases in NKC activity were observed in all other samples. Similar results were obtained when using highly purified NKC (HPNKC) preparations as effector cells [NKC activity (mean +/- SEM); 5:1 (46.2 +/- 4.7, 43.2 +/- 5.0 and 25.2 +/- 2.3) and 10:1 effector-to-target cell ratio (49.3 +/- 4.9, 44.7 +/- 5.2 and 27.2 +/- 2.6, respectively)]. All individual samples tested showed at least a 20% specific lysis increase over their own control. These results show that S. typhi-infected U937 cells are a significantly better target for NKCs than control cells and indicate that intracellular bacteria survival capacity is not a critical factor for infected cells becoming a NKC target. 相似文献
93.
R M González C Cortés J Conde J M Negro J Rodriguez A Tursi B Wüthrich J Carreira 《Annals of allergy》1987,59(2):149-154
We have studied the cross-reactivity between L. perenne, S. cereale, P. pratense, C. dactylon, and Ph. communis. The results obtained demonstrate that L. perenne, S. cereale, and P. pratense have strong cross-reactivity. C. dactylon has a number of allergens that cross-react with the rest of the grasses studied but they are minor allergens. Ph. communis possesses a moderate cross-reactivity with the species of the group but it has, as well, individual allergens. 相似文献
94.
Lucía Núñez Ruth A. Valero Laura Senovilla Sara Sanz-Blasco Javier García-Sancho Carlos Villalobos 《The Journal of physiology》2006,571(1):57-73
Store-operated Ca2+ entry (SOCE) is a ubiquitous Ca2+ influx pathway involved in control of multiple cellular and physiological processes including cell proliferation. Recent evidence has shown that SOCE depends critically on mitochondrial sinking of entering Ca2+ to avoid Ca2+ -dependent inactivation. Thus, a role of mitochondria in control of cell proliferation could be anticipated. We show here that activation of SOCE induces cytosolic high [Ca2+ ] domains that are large enough to be sensed and avidly taken up by a pool of nearby mitochondria. Prevention of mitochondrial clearance of the entering Ca2+ inhibited both SOCE and cell proliferation in several cell types including Jurkat and human colon cancer cells. In addition, we find that therapeutic concentrations of salicylate, the major metabolite of aspirin, depolarize partially mitochondria and inhibit mitochondrial Ca2+ uptake, as revealed by mitochondrial Ca2+ measurements with targeted aequorins. This salicylate-induced inhibition of mitochondrial Ca2+ sinking prevented SOCE and impaired cell growth of Jurkat and human colon cancer cells. Finally, direct blockade of SOCE by the pyrazole derivative BTP-2 was sufficient to arrest cell growth. Taken together, our results reveal that cell proliferation depends critically on mitochondrial Ca2+ uptake and suggest that inhibition of tumour cell proliferation by salicylate may be due to interference with mitochondrial Ca2+ uptake, which is essential for sustaining SOCE. This novel mechanism may contribute to explaining the reported anti-proliferative and anti-tumoral actions of aspirin and dietary salicylates. 相似文献
95.
96.
Isolation, lactoperoxidase catalyzed radioiodination, and recovery of proteins bound to insoluble immunoadsorbents. 总被引:1,自引:0,他引:1
A method for the direct radioiodination and recovery of proteins specifically absorbed to an insoluble immunoadsorbent is described. The optimal conditions for adsorption, washing, radiolabelling by lactoperoxidase catalyzed iodination, and elution of radiolabelled proteins from the immunoadsorbent have been determined. The technique is a rapid and efficient means of isolating and radioiodinating specific proteins present in biological fluids and has been applied to the detection of immunoglobulin and histocompatibility antigens in mouse cell culture supernates. This method should be particularly applicable in research situations in which the specific antisera are available but the antigen concentration is low or the volume of material to be analyzed is limited. 相似文献
97.
Leone PE Vega ME Jervis P Pestaña A Alonso J Paz-y-Miño C 《Journal of human genetics》2003,48(12):639-641
RB1 is the gene responsible for retinoblastoma, the most common malignant intraocular tumor of infancy and early childhood. There are no reports about this gene in Ecuadorian populations, and only a few studies have been published in Latin America about this subject. There is a spectrum of more than 370 mutations described in the RB1 gene mutation database (http://www.d-lohmann.de/Rb/mutations.html), and alterations have been found in 25 of the 27 exons. During the exon-by-exon analysis of 31 tumor and blood samples from Ecuadorian patients, we found two new mutations and three novel polymorphisms. One of the polymorphisms is located in intron 26 where no alterations of the gene have been described previously. The polymorphisms were found in all of the patients tumor samples, but not in normal population, suggesting there might be a relationship between these polymorphisms and the development of retinoblastoma in the Ecuadorian population.The nucleotide sequence data reported are available in the GenBank database under the accession numbers: AY243567, AY260472, AY260473, AY273783 相似文献
98.
Julio C. lvarez Jos M. García Jos G. De la Campa Javier de Abajo 《Macromolecular chemistry and physics.》1997,198(10):3293-3303
Two series of aromatic polyamides were prepared from m-phenylenediamine (MPD) and 4,4′-diaminodiphenyl sulfone (DDS) in combination with a set of new halogenated diacyl chlorides, namely, 5-fluoroisophthaloyl chloride, 5-chloroisophthaloyl chloride, 5-bromoisophthaloyl chloride and 5-iodoisophthaloyl chloride. The polymers were synthesized in high yields and in high molecular weight (as determined by gel permeation chromatography) by means of the low temperature condensation method. Noticeable changes in the spectral characteristics of the halogen-modified polyisophthalamides were observed compared to those of the corresponding unmodified polyisophthalamides. Slight improvements were observed for the glass transition temperatures, which increased 5–30°C relative to those of the conventional polyisophthalamides. Moreover, a correlation was found between the size of the halogen substituents and the increase in Tg values. Thermogravimetric analysis showed that the new polymers are almost as thermally resistant as the unmodified ones, while solubility in organic solvents was some-what poorer. 相似文献
99.
Cortés-Gutiérrez EI Cerda-Flores RM González-Ramírez D Zúñiga-Charles MA Lazcano-Martínez S Sampayo-Reyes A Leal-Garza CH 《Mutagenesis》2004,19(3):203-205
The aims of this study were to evaluate the mutagenic and cytotoxic activity of mercurous chloride by the micronucleus technique in vivo on the bone marrow of golden Syrian hamsters after a single i.p. drug administration. Forty male golden Syrian hamsters were classified into eight groups: negative control, positive control and six groups treated with different doses of mercurous chloride (1.25, 2.5, 5, 10, 20 and 40 mg/kg). The negative control was injected with physiological saline i.p. and the positive control with cyclophosphamide at a dose of 80 mg/kg i.p. With respect to mutagenic effect, the average number of micronucleated polychromatic erythrocytes (MPE) in hamsters treated with different doses of mercurous chloride was not significant compared with the negative control. With respect to cytotoxic effect, the average polychromatic erythrocyte/red blood cell ratio showed a significant decrease when the doses were higher than the 2.5 mg/kg dose compared with the negative control. In conclusion, this preliminary study shows a cytotoxic effect but not a mutagenic effect of calomel in vivo at one time point (24 h). 相似文献
100.