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991.
992.
Transient expression of keratin 19 is induced in originally negative interfollicular epidermal cells by adhesion of suspended cells 总被引:2,自引:0,他引:2
Dvoránková B Smetana K Chovanec M Lacina L Stork J Plzáková Z Galovicová M Gabius HJ 《International journal of molecular medicine》2005,16(4):525-531
Keratin 19 and nuclear reactivity to an endogenous lectin, galectin-1, represent a potential marker of epidermal stem cells. We detected expression of keratin 19 and nuclear binding sites for galectin-1 in adult cells migrating from the hair follicle, where cells expressing keratin 19 are located in the bulge region. The results were compared with the expression of both markers in cells adhering from suspension prepared from the interfollicular epidermis without keratin-19-positive cells and with nuclear binding sites for galectin-1. The results were compared with data from basal cell carcinomas. All cells were analyzed concerning size, as it is known that cell diameter influences the clonogenic potential of keratinocytes. The major result of this study is the observation of transient expression of keratin 19 and nuclear galectin-1 binding sites in originally negative interfollicular epidermal cells induced by adhesion. These cells were very small in size, similar to basal cells of the interfollicular epidermis or the bulge region of the hair follicle. The influence of the suspension regimen on beta1-integrin expression, cell diameter and growth was also monitored. A population of cells highly positive for beta1 integrin of the same diameter as keratin-19-positive cells insensitive to induction of terminal differentiation by lack of anchorage was characterized. Cells of the same size were also observed in the keratin-19-positive cells of basal cell carcinomas. In conclusion, the expression of poor levels of differentiation induced by cell adhesion is transient. Also, keratin 19 expression should not be exclusively regarded as a marker of stem cell activity. 相似文献
993.
Inflammatory responses and cell adhesion to self-assembled monolayers of alkanethiolates on gold 总被引:1,自引:0,他引:1
The acute inflammatory response and the adhesion of cells to self-assembled monolayers (SAMs) of well-defined surface chemistry was studied in vivo using a rodent air-pouch model of inflammation. SAMs with three different terminal functional groups (OH, COOH and CH3) were implanted in subcutaneous air pouches induced in BALB/c mice. After 24 h, inflammatory cells were recovered from the air pouches and the implants were removed and prepared for observation by scanning electron microscopy (SEM). The implants coated with OH and CH3, were found to cause the highest recruitment of inflammatory cells into the subcutaneous pouches. Polymorphonuclear neutrophils (PMNs) leukocytes predominated over mononuclear cells in inflammatory exudates of SAMs-coated implants, the opposite being found in uncoated implants (controls). CH3-coated implants induced the highest number of inflammatory cells and also the largest percentage of PMNs seen in the subcutaneous pouches. Control and OH-covered implants presented the higher densities of attached inflammatory cells detected by SEM. In contrast, the CH3-coated implants showed a very low density of cells adherent to the implant surface. We conclude that the chemical nature and the degree of hydrophobicity of the surface of implants modulate both the local acute inflammatory reaction and the adhesion of leukocytes. 相似文献
994.
995.
N Sneige S Zachariah T V Fanning R H Dekmezian N G Ordó?ez 《American journal of clinical pathology》1989,92(1):27-35
Twenty cases of metastatic neoplasms in the breast were identified in a series of 1,034 fine-needle aspirations (FNAs) of the breast, of which 389 were malignant. Patients with breast carcinomas in whom metastasis to the contralateral breast developed were excluded from this study. This series consisted of 17 women and 3 men, ranging in age from 28 to 63 years (mean, 49 years). The tumors included oat cell carcinoma (three), melanoma (three), ovarian serous carcinoma (one), bronchogenic adenocarcinoma and squamous carcinoma (four and two, respectively), lymphoma (two), carcinoid (two), transitional cell carcinoma (one), plasma cell myeloma (one), and rhabdomyosarcoma (one). In two patients, the breast mass was the first manifestation of an extramammary cancer (two adenocarcinoma of the lung). Eleven patients died of disseminated cancer shortly after the breast metastasis was diagnosed. In most cases, the aspirates displayed the cytologic features characteristic of the primary tumors, thereby establishing the metastatic nature of the neoplasm. In four cases (two carcinoids, one myeloma, and one rhabdomyosarcoma), the cytologic features were difficult to differentiate from a primary breast carcinoma; however, the final diagnosis was established by electron microscopic examination and immunocytochemical studies on the aspirates. One case (adenocarcinoma of the lung) was misdiagnosed as primary breast carcinoma on both FNA and mastectomy specimen. Because metastatic neoplasms in the breast may mimic primary breast tumors, the authors recommend the following: (1) Evaluation of FNA of breast should be done with complete knowledge of the patient's clinical history. (2) The possibility of metastasis should be suspected in lesions with unusual cytologic patterns. (3) Ancillary studies on FNA can be helpful in interpreting selected cases. 相似文献
996.
C G Gustavsson A Gustafson U Albrechtsson H Lárusdóttir E St?hl C Olin 《Acta medica Scandinavica》1988,223(3):247-253
A clinical series of acute aortic dissections is presented. Twenty cases were of type A and 10 of type B. Acute severe chest pain was common, in type A also blood pressure difference between the arms and aortic regurgitation. The diagnosis was established by echocardiography, computerized tomography and/or aortography. Antihypertensive therapy was instituted immediately after diagnosis and was in type A cases followed by acute surgery unless definite contraindications existed. Of 14 surgically treated type A patients 13 survived the operation. On follow-up 1.5-3.5 years later, 12 patients were still alive and doing well, but the false channel remained open in all cases where it had not been resected totally. Only one of six conservatively treated type A patients survived. Type B dissections were operated on only if conservative therapy failed. Four of five conservatively and two of five surgically treated type B patients survived. 相似文献
997.
998.
Jiří Bártek Vladimir Viklický František Franěk Pavla Angelisová Pavel Dráber Taťána Jarošíková Miloš Němec Hana Verlová 《Immunology letters》1982,4(5):231-235
Five stable hybridoma lines were prepared using the myeloma cell line P3-X63-Ag.653 and spleen cells of mice hyperimmunized by pig transferrin. All hybridomas grew well in mouse peritoneal cavity and produced antibodies of the IgG1 subclass. Antibody preparations obtained from ascitic fluids tested for their capacity of antigen precipitation. No precipitation was obtained with single antibodies and with pairs of antibodies. Three out of 10 possible triads gave clear and sharp precipitation zones and rings in immunodiffusion tests performed in agar gel. All 5 antibodies were shown by quantitative enzyme-immunoassay to be specific for pig transferrin: no cross-reaction was obtained with mouse, human, horse and sheep transferrins. 相似文献
999.
Dr. A. O. Donoso M. B. Zárate 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1983,52(2):277-280
Responses to histamine agonists administered intraventricularly under ether anesthesia were analyzed to evaluate receptor mediation in histamine stimulation of prolactin and LH release in ovariectomized, estradiol-progesterone-treated rats (OVX-E2P-treated rats). Prolactin release was markedly increased by the H2-histamine agonists, 4-methyl histamine and Dimaprit. These effects were antagonized by metiamide, an H2-blocking agent. The H1-histamine agonist, 2-(2-pyridyl)ethylamine (PEA) in high doses released prolactin and its effect was partially prevented by metiamide. Mepyramine, and H1-antagonist, did not exert any effect on the release of prolactin enhanced by the histamine agonists. LH release was significantly increased after 4-methyl histamine administration. Its effect was weak and was blocked by metiamide. Neither Dimaprit nor PEA exhibited action on plasma LH levels. The results obtained with histamine agonists suggest that histamine evokes prolactin release in OVX,E2P-treated rats through H2-receptors. At present, conclusions on H2-receptor mediation in LH release induced by histamine cannot be drawn from these results. The above-mentioned data, however, conclusively discard a significant participation of H1-receptors. 相似文献
1000.
A Balázs 《Haematologia》1976,10(3-4):433-444
The ultrastructural effects of the endogenous inhibitor, granuloid crude extract (GCE), known to control the proliferation of myeloid cells, and of the current hexitol derivative, 1,2 : 5,6-dianhydrogalactitol (DAD) were compared on the rat bone marrow. A single intraperitoneally injected LD50 dose of DAD induces the following changes in the fine structure: The mitochondria become swollen, the matrix less electron-dense, the cristae fragmentate, the ribosomes aggregate, anomalies appear in the perinuclear the cell membranes, and myelin figures and intranuclear bodies develop. Autophagy, degeneration and the phagocytotic activity of the reticulum cells is appreciable in 4 hours after treatment and increase by the 24th hour. The toxic effect of DAD is cell aspecific but in the ultrastructure its myelotropic effect manifests earlier than in erythropoiesis. In contrast, the arrest caused by a single dose of the endogenous granuloid inhibitor [2] is cell-specific and non-toxic. 相似文献