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81.
Assessing the delivery of neutrophils to tissues in neutropenia 总被引:2,自引:2,他引:2
Studies of neutrophil kinetics in neutropenic individuals, as well as clinical observations of variability in the occurrence of infection among patients with neutropenia, have suggested that blood neutrophil counts may not uniformly reflect the effective delivery of neutrophils to extravascular tissues where the cells perform their principal host defense functions. To evaluate this possibility we developed a sensitive, reproducible method of measuring the extravascular delivery of neutrophils to a normal mucosal site of neutrophil turnover. This method is based upon the quantification of neutrophils recoverable from saline mouth wash specimens. Twenty-five mL specimens, obtained in a controlled manner from neutropenic patients and normal subjects, were centrifuged and the sediments resuspended in 1.0 mL Hank's buffer with 2 micrograms acridine orange, incubated at 37 degrees C for 15 minutes, and then examined in a hemocytometer chamber by fluorescence microscopy. Neutrophils could be clearly distinguished by their characteristic fluorescence and were counted. With this method as few as 1,500 neutrophils were detected reliably in mouth wash specimens. Mucosal neutrophil counts varied less than 10% with repeated sampling of individual subjects over 5-day periods and were consistently greater than 1.3 X 10(5)/specimen in non-neutropenic individuals. Although profound neutropenia was generally reflected by lower than normal oral mucosal neutrophil counts, these counts were significantly higher in individuals with chronic severe neutropenia (blood neutrophils less than 300/mm3) than in patients with acute neutropenia of comparable severity that had developed following chemotherapy. Also, in individuals recovering from profound neutropenia, neutrophils usually reappeared earlier in mouth wash specimens than in blood, and oral mucosal neutrophil counts attained recovery levels more rapidly than did blood counts. This phenomenon was particularly evident in an individual with cyclic neutropenia. Moreover, mucosal neutrophils could occasionally be detected in profoundly neutropenic patients when neutrophils were not present in blood samples. These findings indicate that mucosal neutrophil counts in individuals with neutropenia provide information about the delivery of neutrophils to tissues that may not be apparent from blood neutrophil counts alone. 相似文献
82.
Intraparental Inconsistency: The Influence of Parenting Behaviors on Aggression and Depression in Children 下载免费PDF全文
Miguel Á. Carrasco Francisco Pablo Holgado‐Tello Miguel Ángel RodrÍguez Serrano 《Family relations》2015,64(5):621-634
The authors examined several different predictive and mediation models of longitudinal parental inconsistency over a 3‐year time span. They hypothesized that parental behavior (communication/affection, kindness, and positive control) mediated the relationship between parental inconsistency (mother or father) and two emotional problems in children: (a) aggression and (b) depression. Data were obtained from a 3‐wave study (2007, 2008, and 2009) of 523 Spanish families with children ranging from 9–15 years of age at the beginning of Wave 1 (41.3% boys). Structural equation models revealed that multiple dimensions of parenting (mother or father) fully or partially mediated the relationship between longitudinal parental inconsistency and the child's adjustment. Communication/affection and kindness are the main processes through which parental inconsistency affects a child's aggression and depression. These results represent an important contribution to the improvement of parenting models of relationships between parental inconsistency and child adjustment. 相似文献
83.
84.
Karvandi Elika Hanrahan John Gerrard Khan Danyal Zaman Boloux Pierre-Marc Bremner Fion Cabrilo Ivan Dorward Neil Grieve Joan Jackson Sue Jimenez Glenda Serrano Inma Nowak Victoria Anne Kolias Angelos Baldeweg Stephanie E. Marcus Hani Joseph 《Pituitary》2022,25(4):673-683
Pituitary - Pituitary adenomas affect patients’ quality-of-life (QoL) across several domains, with long-term implications even following gross-total resection or disease remission. While... 相似文献
85.
Calcineurin controls nerve activity-dependent specification of slow skeletal muscle fibers but not muscle growth 总被引:18,自引:0,他引:18 下载免费PDF全文
86.
Espinet B Solé F Salido M Lloveras E Abella E Besses C Serrano S Woessner S Florensa L 《Haematologica》2000,85(6):607-612
BACKGROUND AND OBJECTIVE: Cross-species color banding (RxFISH) is a new FISH technology based on the use of differentially labeled gibbon chromosome probes to obtain a specific color banding pattern for each human chromosome. The aim of the study was to test the RxFISH technique for better characterization of complex karyotypes in patients with T-prolymphocytic leukemia (T-PLL). DESIGN AND METHODS: The study evaluated the cross-species color banding technique in four patients affected with T-PLL previously studied by conventional cytogenetics. RESULTS: All patients showed an abnormal karyotype and three of them had a complex karyotype. The involvement of 14q11 in all four cases, the gain of 8q in three cases and a loss of chromosome 10, 15 and 17 and a gain of chromosome 21 in two cases were noted. The RxFISH technique identified from 2 to 7 not previously recognized aberrations per case and confirmed the inv(14)(q11q32). INTERPRETATION AND CONCLUSIONS: To our knowledge, this is the first application of RxFISH to characterize chromosomal rearrangements in T-cell neoplasms. RxFISH gave rapid and easy identification of chromosome rearrangements that were difficult to recognize by conventional cytogenetics. Using this new technology we identified 15 rearrangements not detected by conventional cytogenetics. 相似文献
87.
Lourdes Serrano Paloma Martínez-Redondo Anna Marazuela-Duque Berta N. Vazquez Scott J. Dooley Philipp Voigt David B. Beck Noriko Kane-Goldsmith Qiang Tong Rosa M. Rabanal Dolors Fondevila Purificación Mu?oz Marcus Krüger Jay A. Tischfield Alejandro Vaquero 《Genes & development》2013,27(6):639-653
The establishment of the epigenetic mark H4K20me1 (monomethylation of H4K20) by PR-Set7 during G2/M directly impacts S-phase progression and genome stability. However, the mechanisms involved in the regulation of this event are not well understood. Here we show that SirT2 regulates H4K20me1 deposition through the deacetylation of H4K16Ac (acetylation of H4K16) and determines the levels of H4K20me2/3 throughout the cell cycle. SirT2 binds and deacetylates PR-Set7 at K90, modulating its chromatin localization. Consistently, SirT2 depletion significantly reduces PR-Set7 chromatin levels, alters the size and number of PR-Set7 foci, and decreases the overall mitotic deposition of H4K20me1. Upon stress, the interaction between SirT2 and PR-Set7 increases along with the H4K20me1 levels, suggesting a novel mitotic checkpoint mechanism. SirT2 loss in mice induces significant defects associated with defective H4K20me1–3 levels. Accordingly, SirT2-deficient animals exhibit genomic instability and chromosomal aberrations and are prone to tumorigenesis. Our studies suggest that the dynamic cross-talk between the environment and the genome during mitosis determines the fate of the subsequent cell cycle. 相似文献
88.
M.J. Parada Blázquez D. Rodríguez Vargas J. Mohigefer Barrera J.J. Borrero Martín B. Vargas Serrano 《Radiologia》2021,63(2):159-169
ObjectiveTo review the pathophysiology of Fontan-associated liver disease, its histologic changes, and its radiologic manifestations.ConclusionsFontan-associated liver disease is the result of a set of structural and functional changes in the liver that occur secondary to hemodynamic changes brought about by Fontan surgery. The radiologic manifestations of Fontan-associated liver disease consist of changes in the size and shape of the liver, alterations in the signal intensity or pattern of enhancement, abnormalities in the vascular structures, and focal lesions, which include benign nodules with intense uptake in the arterial phase and hepatocellular carcinoma. Radiologists need to be familiar with this disease and its complications, because the number of patients who undergo Fontan surgery continues to increase, and these patients undergo an increasing number of imaging tests. 相似文献
89.
Susanne Krämer James Lucas Francisca Gamboa Miguel Peñarrocha Diago David Peñarrocha Oltra Marcelo Guzmán-Letelier Sanchit Paul Gustavo Molina Lorena Sepúlveda Ignacio Araya Rubén Soto Carolina Arriagada Anne W Lucky Jemima E Mellerio Roger Cornwall Fatimah Alsayer Reinhard Schilke Mark Adam Antal Fernanda Castrillón Camila Paredes Maria Concepción Serrano Victoria Clark 《Special care in dentistry》2020,40(Z1):3-81
90.
Involvement of the carboxyl-terminal domain of tubulin in the regulation of its assembly. 总被引:21,自引:6,他引:21 下载免费PDF全文
L Serrano J de la Torre R B Maccioni J Avila 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(19):5989-5993
Limited proteolysis of phosphocellulose-purified tubulin with subtilisin resulted in cleavage of both alpha and beta tubulin subunits, with the formation of two major fragments (S alpha, and S beta, 48 kDa) and a small peptide (4 kDa) containing the carboxyl-terminal region of tubulin. Interestingly, tubulin cleaved under the present conditions showed an increased ability to assemble into large polymers in the absence of MAPs and under conditions that do not promote assembly of undigested tubulin--i.e., low magnesium concentrations and the absence of taxol and polyalcohols. The critical concentrations for the subtilisin-cleaved tubulin assembly was similar to that of MAPs-promoted tubulin assembly. Assembly product from subtilisin-cleaved tubulin consisted mainly of protofilament bundles, hooked polymer, and open tubules, structures showing equatorial and longitudinal spacings of 50 and 40 A, respectively. The existence of junctions between polymer walls indicates that the carboxyl-terminal removal facilitates polymer-polymer interactions. These results, together with previous studies on the involvement of the carboxyl-terminal domain of tubulin in its interaction with MAP-2, suggest a regulatory role for this domain in tubulin assembly. Thus, in general terms the tubulin molecule can be analyzed as a protein containing two essential domains with functional significance, one domain playing a major role in self-association and the other (the carboxyl-terminal moiety) playing a regulatory role in modulating the interactions responsible for self-association. 相似文献