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91.
M Blanca C Mayorga E Perez R Suau C Juarez J M Vega M J Carmona M Perez-Estrada J Garcia 《Journal of immunological methods》1992,153(1-2):99-105
The influence of two different carriers, poly-L-lysine (PLL) and human serum albumin (HSA) in the binding of specific IgE antibodies to the benzyl penicilloyl hapten (BPO) was determined in a solid-phase assay. Serum samples from patients with a history of immediate reaction to penicillin and which had shown the presence of IgE antibodies to BPO were used. Benzyl penicilloyl derivatized cellulose discs were prepared using PLL of different molecular weight and HSA as carriers. These were treated with different molar ratios of benzyl penicillin. These reagents were compared for uptake of BPO-specific IgE using a pool of sera in a radioallergosorbent test (RAST) type assay. Two PLL systems and two HSA systems were finally compared using 26 individual sera. RAST values were compared by Kruskal-Wallis and Wilcoxon tests. The relationships between the four different assays were evaluated by determining Pearson correlation coefficients and the concordance by determining intraclass correlation coefficients (ICC). Analysis of means by the Wilcoxon test revealed significant differences (P less than 0.01) only when the different carrier assays were compared. The correlation coefficients between all the assays were significant (P less than 0.0001), but the ICC was low when the different carrier assays were compared. These results indicate that the nature of the carriers studied (PLL and HSA) influences the capacity for binding IgE antibodies in the RAST procedure. The differences observed indicate that one conjugate cannot be substituted for the other in the determination of IgE antibodies to BPO and that BPO-PLL is preferable. 相似文献
92.
Antonio Arnaiz-Villena Jose Palacio-Grüber Ignacio Juarez Adrian Lopez-Nares Jorge Nieto Cristina Campos Jose Manuel Martin-Villa 《Human immunology》2019,80(2):91-92
Uros people live in floating reed islands in Titikaka Lake in front of Puno town (Peru). They could have started Tiwanaku culture and shared genes and culture with Pacific Islanders; it is particularly relevant the giant hat covered men statues found in both Tiwanaku at Titikaka Lake shore and Easter Island (3700 km far from Chile in Pacific Ocean). These giants monoliths are very similar one another and unique in America and Pacific Islands. The following HLA alleles are shared in a specifically high frequency between Uros and Pacific Islanders : HLA-A*24:02, HLA-B*35:05, HLA-B*48:01, HLA-DRB1*04:03, HLA-DRB1*08:02 and HLA-DRB1*09:01. Uros also have 3 unique HLA haplotypes: A*24:02-B*15:04 ? DRB1*14:02-DQB1*03:01, A*68:01:02-B*35:05-DRB1*04:03-DQB1*03:02, A*24:02-B*48:01-DRB1*04:03-DQB1*03:02. Also Uros seem to be one of the most ancient population in Titikaka Lake that could have started Tiwanaku culture. Prehistoric contacts between Amerindians and Pacific Islanders are strongly suggested by genetic and cultural traits. It is not discarded that Uros could have come from Pacific Islands: Uros show melanic skin and are dolichocephalic; in contrast, surrounding Aymara people have a clear skin and are brachicephalic. The Kon-Tiki project led by Thor Heyerdahl showed that a simple sailing is possible between Peru and Polynesia Islands; also, the most ancient skull found in America is of black origin: Luzia, suggesting that first America peopling was also carried out by Black/coloured people. 相似文献
93.
Ruling out acute myocardial infarction. A prospective multicenter validation of a 12-hour strategy for patients at low risk 总被引:13,自引:0,他引:13
T H Lee G Juarez E F Cook M C Weisberg G W Rouan D A Brand L Goldman 《The New England journal of medicine》1991,324(18):1239-1246
BACKGROUND. Although previous investigations have suggested that 24 hours is required to exclude acute myocardial infarction in patients who are admitted to a coronary care unit for the evaluation of acute chest pain, we hypothesized that a 12-hour period might be adequate for patients with a low probability of infarction at the time of admission. METHODS. Using a Bayesian model, we developed a strategy to identify candidates for a shorter period of observation from an analysis of a derivation set of 976 patients with acute chest pain who were admitted to three teaching and four community hospitals. In the derivation set, patients whose clinical characteristics in the emergency room predicted a low (less than or equal to 7 percent) probability of myocardial infarction had only a 0.4 percent risk of infarction if they had neither abnormal levels of cardiac enzymes nor recurrent ischemic pain during the first 12 hours of hospitalization. In an independent testing set of 2684 patients from the seven hospitals, 957 admitted patients (36 percent) were classified as candidates for this 12-hour period of observation according to a previously published multivariate algorithm. Few of these patients were actually transferred from a monitored setting at 12 hours. RESULTS. Of the 771 candidates for a 12-hour period of observation who did not have enzyme abnormalities or recurrent pain during the first 12 hours, 4 (0.5 percent) were subsequently found to have acute myocardial infarction, and only 3 (0.4 percent) died after primary cardiac arrests, all of which occurred three to five days after admission. Rates of other major cardiovascular complications were low in the patients who might have been transferred from the coronary care unit after 12 hours with this strategy. In patients with a higher initial risk of infarction, the standard strategy of 24-hour observation identified all but 11 of 739 acute myocardial infarctions (1 percent). CONCLUSIONS. Emergency room clinical data can be used to identify a large subgroup of patients for whom a 12-hour period of observation is normally sufficient to exclude acute myocardial infarction. Patient-specific evaluation and treatment can then proceed without the restrictions imposed by "rule-out" protocols for myocardial infarction. 相似文献
94.
Willian Juarez Granucci Guirro Karina Maria Salvatore Freitas Guilherme Janson Marcos Roberto de Freitas Camila Leite Quaglio 《The Angle orthodontist》2016,86(1):3
Objective:To compare the postretention stability of maxillary incisors alignment in subjects with Class I and II malocclusion treated with or without extractions.Materials and Methods:The sample comprised 103 subjects with initial maxillary anterior irregularity greater than 3 mm and was divided into four groups: group 1 comprised 19 patients with Class I malocclusion treated with nonextraction (mean initial age = 13.06 years); group 2 comprised 19 patients with Class II malocclusion treated with nonextraction (mean initial age = 12.54 years); group 3 comprised 30 patients with Class I malocclusion treated with extractions (mean initial age = 13.16 years); group 4 comprised 35 patients with Class II malocclusion treated with extractions (mean initial age = 12.99 years). Dental casts were obtained at three different stages: pretreatment (T1), posttreatment (T2), and long-term posttreatment (T3). Maxillary incisor irregularity and arch dimensions were evaluated. Intergroup comparisons were performed by one-way analysis of variance followed by Tukey tests.Results:In the long-term posttreatment period, relapse of maxillary crowding and arch dimensions was similar in all groups.Conclusion:Changes in maxillary anterior alignment in Class I and Class II malocclusions treated with nonextractions and with extractions were similar in the long-term posttreatment period. 相似文献
95.
Fabricio M. Locatelli S. Pamela Cajal Paola A. Barroso Juan J. Lauthier María C. Mora Marisa Juarez Hirotomo Kato Julio R. Nasser Yoshihisa Hashiguchi Masataka Korenaga Jorge D. Marco 《Acta tropica》2014
American tegumentary leishmaniasis (ATL) is a group of zoonotic diseases caused by kinetoplastid flagellates of the genus Leishmania. A total of 66 patients diagnosed as positive ATL cases from northwest Argentina were included in this study. Leishmania stocks were isolated in vitro and analyzed over promastigote cultures sown on FTA through nested PCR and sequence of cytochrome b (cyt b). The molecular analysis resulted in the incrimination of L. (Viannia) braziliensis as the predominant species in the studied area, identifying two genotypes of L. (V.) braziliensis, 24 cases of Ab-1 cyt b and 41 cases of Ab-2 cyt b. One L. (V.) guyanensis strain was obtained from a traveler from the Brazilian Amazon. The prevalence of different genotypes was in agreement with previous studies, suggesting the necessity for new systems to study the genetic diversity in more detail. Most of the cases typified in this study were registered in the area of Zenta Valley (Orán, Hipólito Yrigoyen, and Pichanal cities), pointing a link between genotype and geographical origin of the sample. Sex and age distribution of the patients indicate that the transmission was predominantly associated with rural areas or rural activities, although the results might not exclude the possibility of peri-urban transmission. This work represents, so far, the largest isolation and molecular characterization of ATL cases in Argentina. 相似文献
96.
Acute leukemia and pregnancy 总被引:2,自引:0,他引:2
J Feliu S Juarez A Ordo?ez M L Garcia-Paredes M Gonzalez-Baron J M Montero 《Cancer》1988,61(3):580-584
Acute leukemia was diagnosed in five pregnant patients who received chemotherapy during the course of pregnancy. Three were undergoing chemotherapy at conception. One patient died in the fifth month of pregnancy and the anatomic study of the fetus was normal. Four babies had low birth weights at birth. Of the four one was born prematurely, but without malformations. Later development was normal. The results are reviewed and compared with data from the literature, leading to the conclusion that pregnancy is not an absolute contraindication for cytostatic treatment, except in the first trimester, in which cytostatic treatment should be avoided. 相似文献
97.
L M Molina J A De Diego M Diez I Delgado L De Frutos D Juarez J L Balibrea 《Hepato-gastroenterology》1988,35(2):91-93
A case of papillary adenoma of the gallbladder unassociated with cholelithiasis and showing detachment of part of the growth with obstruction of the common bile duct is described. One the basis of a search of the literature, it would appear that this is the first time such a case has been reported. The bibliography is discussed and a distinction drawn between this kind of adenoma and other benign tumors of the gallbladder. 相似文献
98.
Jose Juarez Gary Clayman Motowo Nakajima Kenneth K. Tanabe Hideyuki Saya Garth L. Nicolson Douglas Boyd 《International journal of cancer. Journal international du cancer》1993,55(1):10-18
The present study was undertaken to determine the role of the metalloproteinase MMP-9 in the invasive phenotype of squamous-cell carcinoma of the oral cavity and the regulation of its expression. Zymographic analysis of conditioned medium from 2 highly invasive squamous-cell-carcinoma cell lines indicated large amounts of an enzyme which was indistinguishable, in size (92 kDa) from the MMP-9 pro-enzyme. Conversion of the 92-kDa gelatinase into a lower-molecular-weight species (84 kDa), identical in size to the activated gelatinase, was evident when both cell lines, which are avid secretors of urokinase, were cultured in the presence of plasminogen. Penetration of an extracellular-matrix-coated filter was dramatically reduced in the presence of the collagenase inhibitor, tissue inhibitor of metalloproteinase-2, suggesting a critical role for MMP-9 in the invasive process. Immunohistochemical studies demonstrating the presence of MMP-9 in tumor cells of resected squamous-cell cancers suggested that secretion of this collagenase by cells in vitro was reflective of the in vivo setting. Since several phorbol-ester response elements are present in the MMP-9 promoter, we determined the role of protein-kinase-C pathways in the regulation of MMP-9 expression in cultured SCC. Treatment of cells with PMA resulted in a more-than-20-fold increase in the level of protein and mRNA. Conversely, culturing of cells in the presence of the protein-kinase-C inhibitor, calphostin-C, led to a dose-dependent decrease in the amount of MMP-9 mRNA and protein, suggesting that the constitutive expression of this collagenase reflects activation of this signal transduction pathway. In summary, our data suggest that, for a sub-population of squamous-cell carcinomas, secreted MMP-9 is an important determinant of the invasive phenotype, and that the expression of this metalloproteinase is regulated by protein-kinase-C pathways. © 1993 Wiley-Liss, Inc. 相似文献
99.
David Encinas-Basurto Jaime Ibarra Josué Juarez María G. Burboa Silvia Barbosa Pablo Taboada 《Journal of microencapsulation》2017,34(3):231-242
The objective of this study is to establish the ability of entrap allyl isothiocyanate (AITC) into polymeric nanoparticles to extend its shelf life and enhance its antiproliferative properties. Natural compounds, such as AITC, have showed multi-targeting activity resulting in a wide-range spectrum of therapeutic properties in chronic and degenerative diseases, conversely with most current pharmaceutical drugs showing single targeting activity and often result in drug resistance after extended administration periods. Apparently, AITC-loaded poly(lactic-co-glycolic acid) nanoparticles (PLGA NPs) reduced AITC degradation and volatility and were able to extend AITC shelf life compared with free AITC (65% vs. 20% in 24?h, respectively). Cell viability and uptake of AITC-loaded nanoparticles were studied in vitro, showing that the protection and sustained release of AITC from polymeric NPs involved a larger toxicity of tumoral cells. These nanoparticles could be used as protective systems for enhancing a biological activity. 相似文献
100.
H Orozco F Juarez M Uribe J Hernandez J Ordorica R Armenta M Aranceta M A Mercado P Santillan A Mendoza 《American journal of surgery》1986,152(5):539-542
In the last 10 years, we operated on 231 patients with hemorrhagic portal hypertension. Most of these patients had some form of liver disease. We performed various surgical procedures: 47 conventional shunts with H grafts and terminolateral portacaval shunts with arterialization of the portal stump, 139 selective Warren shunts, and in those patients in whom a selective portasystemic shunt could not be performed for technical reasons, esophagogastric devascularization in the form of the Sugiura procedure. Forty-five patients were treated with the Sugiura procedure as a one stage or two stage procedure. A total of 68 emergency and elective operations were performed. The operative mortality rate for the emergency thoracic operation was 41 percent and for the abdominal operation, 42 percent. The overall operative mortality rate in the emergency group was 41 percent. The incidence of recurrent variceal bleeding and encephalopathy was 0 in the surviving patients. The survival rate at 3 year follow-up was 40 percent. The elective group was made up of 24 patients. Eighteen patients had a two stage procedure and 6 patients had a one stage procedure. The operative mortality rate for the abdominal operation was 11 percent, whereas that for the thoracic operation was 7 percent. The operative mortality rate for the one stage procedure was 16 percent. The overall operative mortality rate in the elective group was 10.8 percent. None of these patients had recurrent variceal bleeding and encephalopathy developed in only one (5 percent). The encephalopathy was easily controlled with medical treatment. The 3 year survival rate was 83 percent. We conclude that the Sugiura procedure is an effective procedure to treat hemorrhagic portal hypertension when a selective shunt cannot be performed. 相似文献