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排序方式: 共有4373条查询结果,搜索用时 15 毫秒
1.
Nataly Mancette Rijensky Netta R. Blondheim Shraga Eilon Barnea Nir Peled Eli Rosenbaum Aron Popovtzer Solomon M. Stemmer Alejandro Livoff Mark Shlapobersky Neta Moskovits Dafna Perry Eitan Rubin Itzhak Haviv Arie Admon 《Molecular & cellular proteomics : MCP》2020,19(8):1360-1374
Highlights
- •Sufficient tumor tissues are often unavailable large HLA peptidome discovery.
- •Using patient derived xenograft (PDX) tumors can overcome this limitation.
- •The large PDX HLA peptidomes expand significantly those of the original biopsies.
- •The HLA peptidomes of the PDX tumors included many tumor antigens.
2.
3.
Polyamines and Anaerobic Elongation of Rice Coleoptile 总被引:2,自引:0,他引:2
The role of polyamines in the anaerobic elongation of rice (Oryzasativa L.) coleoptiles was studied. The reduced growth of ricecoleoptiles under anoxic conditions was accompanied by a massiveaccumulation of free putrescine. Putrescine was synthesizedfrom arginine in a reaction catalyzed by arginine decarboxylase(ADC). The anoxic titer of putrescine was closely correlatedwith elongation of coleoptiles. In experiments in which putrescineand inhibitors [-difluoromethylarginine (DFMA) and -difluoromethylornithine(DFMO)] of the synthesis of polyamines were exogenously supplied,we demonstrated an absolute requirement for putrescine, synthesizedby ADC, for anaerobic elongation of coleoptiles. The presenceof exogenous putrescine (alone or in combination with DFMA)increased the rate of anaerobic elongation of coleoptile by3040%. (Received December 1, 1988; Accepted June 19, 1989) 相似文献
4.
A strain of Cryptococcus neoformans that was isolated from the cerebrospinal fluid of a human diagnosed as having acquired immunodeficiency syndrome (AIDS), and that produced cutaneous lesions in experimentally infected, normal mice is described. Although no unusual cutaneous manifestations were noted in the patient's records, this isolate of C. neoformans proved to be dermotropic when injected intravenously into CD-1 mice. The LD50 at 28 days post infection ranged from 3.6–7.5×105 cells per mouse, and in vitro growth rate studies demonstrated that this isolate grew well at 35 °C and at 37 °C, but did not grow at 40 °C and higher. This isolate was rhinotropic producing large granulomatous lesions in the nasal tissues. Other cutaneous tissues affected were the periocular tissues, ears, feet and tail, although the granulomas were nodular in structure and less necrotic than the nasal lesions. The brain, lungs, liver, kidneys and spleen also were culture positive for C. neoformans. Histopathologically, each affected tissue examined had large densities of yeast cells and a chronic, granulomatous host response. Animals surviving the infection appeared to develop a commensal-type relationship with the infective yeast. This is the first report of an isolate of C. neoformans from an AIDS patient that has caused cutaneous manifestations in an animal model. The model described in this report may be useful for elucidating pathogenic mechanisms of cryptococcosis, particularly cutaneous manifestations of the disease. 相似文献
5.
Bioflavonoid interaction with rat uterine type II binding sites and cell growth inhibition 总被引:10,自引:0,他引:10
B M Markaverich R R Roberts M A Alejandro G A Johnson B S Middleditch J H Clark 《Journal of steroid biochemistry》1988,30(1-6):71-78
Competition analysis with a number of known bioflavonoids demonstrated that these compounds (luteolin, quercetin, pelargonin) compete for [3H]estradiol binding to cytosol and nuclear type II sites in rat uterine preparations. The inhibition of [3H]estradiol binding to type II sites was specific and these bioflavonoids did not interact with the rat uterine estrogen receptor. Since estradiol stimulation of nuclear type II sites in the rat uterus is highly correlated with cellular hypertrophy and hyperplasia, we assessed the effects of these compounds on the growth of MCF-7 human breast cancer cells in culture and on estradiol stimulation of uterine growth in the immature rat. The data demonstrated that addition of quercetin (5-10 micrograms/ml) to MCF-7 cell cultures resulted in a dose-dependent inhibition of cell growth (DNA/flask). This effect was reversible by removal of quercetin from the culture medium, or by the addition of 10 nM estradiol-17 beta to these cell cultures containing this bioflavonoid. Since estradiol-17 beta (10 nM) stimulated nuclear type II sites and proliferation of MCF-7 cells, we believe bioflavonoid inhibition of MCF-7 cell growth may be mediated through an interaction with nuclear type II sites. This hypothesis was confirmed by in vivo studies which demonstrated that injection of luteolin or quercetin blocked estradiol stimulation of nuclear type II sites in the immature rat uterus and this correlated with an inhibition of uterine growth (wet and dry weight). These studies suggest bioflavonoids, through an interaction with type II sites, may be involved in cell growth regulation. 相似文献
6.
Robert A. Hammer Alejandro Ochoa Cesar Fernandez Atilla Ertan Akira Arimura 《Peptides》1992,13(6):1175-1179
Neurotensin and somatostatin have both been shown to inhibit gastric acid secretion, but no interaction between these peptides has been demonstrated. To determine whether somatostatin might be a mediator of neurotensin's effect on pentagastrin-stimulated gastric acid secretion, we performed the following three experiments. First, we collected 0.2-ml samples of portal venous blood as frequently as every 5 min, and we confirmed a significant release of somatostatin-like immunoreactivity into portal venous blood during neurotensin-induced inhibition of acid secretion. This release of somatostatin-like immunoreactivity and inhibition of acid secretion were only seen in pentobarbital-anesthetized rats, but no sustained release of somatostatin-like immunoreactivity or inhibition of acid secretion occurred in urethane-anesthetized animals. In the second experiment, we analyzed portal plasma by high pressure liquid chromatography, and found that portal somatostatin-like immunoreactivity in blood collected during neurotensin infusion was composed of a single peak corresponding to somatostatin-14. In the third experiment, we found that infusion of antibody to somatostatin prevented neurotensin from inhibiting pentagastrin-stimulated acid secretion. Taken together, these data show that somatostatin, possibly from the stomach itself, is a necessary mediator of neurotensin's inhibitory effect in pentobarbital-anesthetized rats. 相似文献
7.
Antitumor evaluation of marine algae in Argentina 总被引:3,自引:3,他引:0
8.
Rabbit skeletal muscle protein phosphatases C-I and C-II have been previously isolated as two proteins of Mr = approximately 35,000. Both enzymes display broad substrate specificities but have distinct enzymatic properties in regard to their susceptibility to heat-stable protein inhibitor-2 and their response to divalent cations. Monoclonal antibodies against both protein phosphatase C-I and C-II were produced by fusion of spleen cells of immunized BALB/c mice with SP2/0-Ag14 mouse myeloma cells. The products of the hybrid cells were screened by solid phase radioimmunoassay for the production of antibodies to protein phosphatase C-I and C-II. Positive cells were cloned and injected into mice to produce ascitic fluids. Ten monoclonal antibodies against phosphatase C-I and eight monoclonal antibodies against phosphatase C-II were obtained. These antibodies were characterized with regard to their relative binding affinities to the two protein phosphatases and their abilities to inhibit the phosphorylase phosphatase activities of the two enzymes. All ten of the phosphatase C-I monoclonal antibodies inhibited the phosphorylase phosphatase activity of phosphatase C-I, and three of these also inhibited phosphatase C-II. Only one of the eight antibodies to phosphatase C-II was inhibitory and inhibited the activities of both phosphatase C-I and C-II. Examination of the binding of these monoclonal antibodies by a solid phase radioimmunoassay showed that eight of the ten phosphatase C-I antibodies cross-reacted with phosphatase C-II, while all eight of the phosphatase C-II antibodies cross-reacted with phosphatase C-I. These findings show that phosphatases C-I and C-II possess common antigenic determinant(s) and may, therefore, be structurally related proteins. 相似文献
9.
Alejandro Lynch Allan J. Baker 《Evolution; international journal of organic evolution》1994,48(2):351-359
We investigated cultural evolution in populations of common chaffinches (Fringilla coelebs) in the Atlantic islands (Azores, Madeira, and Canaries) and neighboring continental regions (Morocco and Iberia) by employing a population-memetic approach. To quantify differentiation, we used the concept of a song meme, defined as a single syllable or a series of linked syllables capable of being transmitted. The levels of cultural differentiation are higher among the Canaries populations than among the Azorean ones, even though the islands are on average closer to each other geographically. This is likely the result of reduced levels of migration, lower population sizes, and bottlenecks (possibly during the colonization of these populations) in the Canaries; all these factors produce a smaller effective population size and therefore accentuate the effects of differentiation by random drift. Significant levels of among-population differentiation in the Azores, in spite of substantial levels of migration, attest to the differentiating effects of high mutation rates of memes, which allow the accumulation of new mutants in different populations before migration can disperse them throughout the entire region. 相似文献
10.
Mayrel Palestino-Domínguez Alejandro Escobedo-Calvario Soraya Salas-Silva Moises Vergara-Mendoza Veronica Souza-Arroyo Roberto Lazzarini Roxana Miranda-Labra Leticia Bucio-Ortiz María Concepción Gutiérrez-Ruiz Luis E. Gomez-Quiroz 《Journal of biochemical and molecular toxicology》2023,37(4):e23302
Alcohol-induced pancreas damage remains as one of the main risk factors for pancreatitis development. This disorder is poorly understood, particularly the effect of acetaldehyde, the primary alcohol metabolite, in the endocrine pancreas. Hepatocyte growth factor (HGF) is a protective protein in many tissues, displaying antioxidant, antiapoptotic, and proliferative responses. In the present work, we were focused on characterizing the response induced by HGF and its protective mechanism in the RINm5F pancreatic cell line treated with ethanol and acetaldehyde. RINm5F cells were treated with ethanol or acetaldehyde for 12 h in the presence or not of HGF (50 ng/ml). Cells under HGF treatment decreased the content of reactive oxygen species and lipid peroxidation induced by both toxics, improving cell viability. This effect was correlated to an improvement in insulin expression impaired by ethanol and acetaldehyde. Using a specific inhibitor of Erk1/2 abrogated the effects elicited by the growth factor. In conclusion, the work provides mechanistic evidence of the HGF-induced-protective response to the alcohol-induced damage in the main cellular component of the endocrine pancreas. 相似文献