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101.
Analysis of cells obtained by bronchial lavage of infants with respiratory syncytial virus infection
ML Everard A Swarbrick M Wrightham J McIntyre C Dunkley PD James HF Sewell AD Milner 《Archives of disease in childhood》1994,71(5):428-432
To study the cellular infiltrate that occurs within the airways of infants with respiratory syncytial virus bronchiolitis, samples of airways secretions were obtained by bronchial lavage from the lower respiratory tract of infants ventilated for this condition and from the upper airway of non-intubated infants with this disorder using nasopharyngeal aspirates. Cytospin samples were prepared so that differential cell counts could be performed on the cells obtained and alkaline phosphatase-antialkaline phosphatase immunocytochemical analysis of lymphocyte subsets was carried out using a panel of monoclonal antibodies, which included anti-CD3, anti-CD4, anti-CD8, anti-CD19, and anti-TcR gamma delta. Results from the lower and upper airways were similar. Large numbers of inflammatory cells were obtained, of which neutrophils accounted for a median of 93% in the upper airway and 76% in the lower airway. The numbers of CD8 positive cells detected were small and consistently less than CD4 positive cells, median CD4:CD8 ratios being 22.5:1 and 15:1 for the lower and upper airways. CD19 positive cells were rarely observed and no gamma delta positive lymphocytes were detected. These results indicate that neutrophils probably play a major part in causing symptoms in these infants. They do not support the concept that excessive lymphocyte mediated cytotoxic activity is principally responsible for the pathology in respiratory syncytial virus bronchiolitis. 相似文献
102.
103.
Differential binding of erythroid and myeloid progenitors to fibroblasts and fibronectin 总被引:11,自引:2,他引:9
Using a novel coverslip-transfer culture technique, we recently demonstrated that primitive erythroid burst-forming units (BFU-E) can migrate, proliferate, and differentiate in intimate association with stromal fibroblastoid cells in the presence of serum proteins and erythropoietin. No other exogenous hemopoietic growth factors are required. Most of the colonies that develop in this system are very large erythroid bursts, and very few granulocyte-macrophage (GM) colonies are observed. In this report, we present data indicating that the predominance of erythroid burst colonies in this culture system is due to preferential binding of primitive erythroid progenitors to the stromal fibroblastoid cells and not to differential stimulation of these erythroid progenitors by these cells. We next show that the binding of BFU-E to stromal cells is blocked by anti-fibronectin antibodies. Finally, we demonstrate the preferential binding of BFU-E to fibronectin by using glass coverslips or Petri dishes coated with purified human plasma fibronectin. The binding is blocked by a monoclonal antibody specific for the cell-binding domain of fibronectin. We conclude that: primitive erythroid progenitors bind strongly whereas G and/or M progenitors (CFU-G/M) bind only weakly to fibronectin; primitive erythroid progenitors bind to the cell-binding domain on the fibronectin molecule; and erythroid progenitors and precursors remain bound to fibronectin throughout differentiation. 相似文献
104.
Parenchymal cysts of the lower neck 总被引:4,自引:0,他引:4
Som PM; Sacher M; Lanzieri CF; Solodnik P; Cohen BA; Reede DL; Bergeron RT; Biller HF 《Radiology》1985,157(2):399-406
We report on the appearance of parathyroid, thyroid, and cervical thymic cysts on computed tomography (CT) scans. The differential diagnostic considerations include thyroglossal and branchial cleft cysts, cystic hygromas, primary and metastatic tumors, dermoids, teratomas, choristomas, tracheoesophageal and cervical bronchogenic cysts, as well as cystic neuromas, abscesses, and lipomas. Most cannot be differentiated using CT alone and require clinical observations, laboratory testing, and surgical and histologic findings for definitive diagnosis. Our experience with these rare lesions is reported, and the differential diagnoses are discussed. 相似文献
105.
Autism and multiple exostoses associated with an X;8 translocation occurring within the GRPR gene and 3' to the SDC2 gene 总被引:2,自引:0,他引:2
Ishikawa-Brush Y; Powell JF; Bolton P; Miller AP; Francis F; Willard HF; Lehrach H; Monaco AP 《Human molecular genetics》1997,6(8):1241-1250
An X;8 translocation was identified in a 27-year-old female patient
manifesting multiple exostoses and autism accompanied by mental retardation
and epilepsy. Through molecular analysis using yeast artificial chromosomes
(YACs) and cosmid clones, the translocation breakpoint was isolated and
confirmed to be reciprocal within a 5'-GGCA- 3' sequence found on both X
and 8 chromosomes without gain or loss of a single nucleotide. The
translocation breakpoint on the X chromosome occurred in the first intron
of the gastrin-releasing peptide receptor (GRPR) gene and that on
chromosome 8 occurred approximately 30 kb distal to the 3' end of the
Syndecan-2 gene (SDC2), also known as human heparan sulfate proteoglycan or
fibroglycan. The GRPR gene was shown to escape X-inactivation. A dosage
effect of the GRPR and a position effect of the SDC2 gene may, however,
contribute the phenotype observed in this patient since the orientation of
these genes with respect to the translocation was incompatible with the
formation of a fusion gene. Investigation of mutations in these two genes
in unrelated patients with either autism or multiple exostoses as well as
linkage and association studies is needed to validate them as candidate
genes.
相似文献
106.
Organization of the neurons of origin of the descending pathways from the ferret superior colliculus
M. A. Meredith L. K. Miller A. S. Ramoa H. R. H. Clemo M. Behan 《Neuroscience research》2001,40(4):301-313
The superior colliculus (SC), through its descending projections to the brainstem and spinal cord, is involved in initiating sensory-driven orienting behaviors. Ferrets are carnivores that hunt both above and below ground using visual (and auditory) cues in the daylight but non-visual cues in darkness and in subterranean environments. The present investigation sought to determine whether the ferret SC shows organizational features similar to those found in other visually dominant animals (e.g. cats), or whether characteristics of colliculi from non-visually dominant animals (e.g. rodents) prevail. Injection of retrograde tracer into the identified targets of the colliculus (cervical spinal cord, the contralateral pontomedullary reticular formation, or the ipsilateral pontine reticular formation) labeled tectospinal, crossed tectoreticular, and ipsilateral tectoreticular neurons, respectively, within the adult ferret SC. Labeled tectospinal and crossed tectoreticular neurons were far outnumbered by neurons with ipsilateral reticular projections. Like those of their visually dominant relatives, ferret tectospinal neurons were well represented throughout the anterior-posterior extent of the SC and crossed tectoreticular neurons tended to be distributed more broadly across the intermediate gray layer than those of rodents. Thus, even though ferrets perform well as subterranean predators where non-visual cues initiate orienting behaviors, these anatomical characteristics indicate that their colliculi are organized similar to that of their visually dominant, carnivorous relatives. 相似文献
107.
Mandy Krumbiegel Francesca Pasutto Ursula Schl?tzer-Schrehardt Steffen Uebe Matthias Zenkel Christian Y Mardin Nicole Weisschuh Daniela Paoli Eugen Gramer Christian Becker Arif B Ekici Bernhard HF Weber Peter Nürnberg Friedrich E Kruse André Reis 《European journal of human genetics : EJHG》2011,19(2):186-193
Genetic and nongenetic factors contribute to development of pseudoexfoliation (PEX) syndrome, a complex, age-related, generalized matrix process frequently associated with glaucoma. To identify specific genetic variants underlying its etiology, we performed a genome-wide association study (GWAS) using a DNA-pooling approach. Therefore, equimolar amounts of DNA samples of 80 subjects with PEX syndrome, 80 with PEX glaucoma (PEXG) and 80 controls were combined into separate pools and hybridized to 500K SNP arrays (Affymetrix). Array probe intensity data were analyzed and visualized with expressly developed software tools GPFrontend and GPGraphics in combination with GenePool software. For replication, independent German cohorts of 610 unrelated patients with PEX/PEXG and 364 controls as well as Italian cohorts of 249 patients and 190 controls were used. Of 19, 17 SNPs showing significant allele frequency difference in DNA pools were confirmed by individual genotyping. Further single genotyping at CNTNAP2 locus revealed association between PEX/PEXG for two SNPs, which was confirmed in an independent German but not the Italian cohort. Both SNPs remained significant in the combined German cohorts even after Bonferroni correction (rs2107856: Pc=0.0108, rs2141388: Pc=0.0072). CNTNAP2 was found to be ubiquitously expressed in all human ocular tissues, particularly in retina, and localized to cell membranes of epithelial, endothelial, smooth muscle, glial and neuronal cells. Confirming efficiency of GWAS with DNA-pooling approach by detection of the known LOXL1 locus, our study data show evidence for association of CNTNAP2 with PEX syndrome and PEXG in German patients. 相似文献
108.
de Groot RI Dekkers OM Herold IH de Jonge E Arbous MS 《Critical care (London, England)》2011,15(1):R19
Introduction
Unplanned extubation (UE) is a frequent event during mechanical ventilation in critically ill patients and might be associated with increased morbidity and mortality. However, detailed knowledge of risk factors and outcomes after UE is lacking. 相似文献109.
T. Zieliski M. Sobieszczaska-Maek A. Browarek M. Piotrowska M. Zakliczyski P. Przybyowski K. Roguski J. Sadowski M. Zembala J. Korewicki POLKARD HF investigators 《Transplantation proceedings》2009,41(8):3166-3170
Introduction
The aim of the study was to analyze the influence of body weight of the adult heart recipient on the chance to obtain a transplant.Methods
We analyzed the data from all 658 patients listed for heart transplantation.Results
During the follow-up period, 325 (49%) of listed patients underwent transplantation with 102 (15%) succumbing before heart transplantation. The mean weight of transplanted patients was 73.7 ± 13.7 kg and 81.2 ± 15.4 kg for those not transplanted (P < .00001). Patients were divided according to body weight in two groups: light = below 80 kg (n = 360) or heavy ≥ 80 kg or above (n = 297). On the transplant list, 111 heavy patients (37%) versus 213 light patients (59%) underwent the procedure, a significant difference.The waiting time among light patients was 255 versus heavy patients of 395 days (P < .005).There was a similar number of deaths before transplantation among the light (n = 56 360 patients; 15.5%) versus the heavy group (49/297; 16%).Upon multivariate Cox mode analysis independent factors related to not receiving a heart transplant were greater weight, systolic blood pressure, pulmonary vascular resistance, Heart Failure Survival Score (HFSS) score and lower N-terminal pro-brain natriuretic peptide (NTproBNP) levels.Conclusions
Among adult heart transplant candidates, the chance to receive a heart transplant significantly decreased when the recipient's weight exceeded 80 kg. Patients with a body weight more than 110 kg had a poor chance to receive a heart transplantation. 相似文献110.
Bioassay-guided fractionation of the active n-BuOH extract of the starfish Culcita novaeguineae resulted in the isolation of three new sulfated steroidal glycosides (asterosaponins) 1, 2 and 3, as active compounds causing morphological abnormality of Pyricularia oryzae mycelia. Compounds 1-3 possess the same pentasaccharide moiety, beta-D-fucopyranosyl-(1→2)-alpha-L-arabinopyranosyl- ( 1 → 4 )-[- beta-D- quinovopyranosyl- ( 1 →2 ) ]-beta-D-xylopyranosyl- ( 1 → 3 )-beta-D-quinovopyranosyl, linked to C-6 of 3beta-sulfated steroidal aglycones and differ from each other in the side chains. 相似文献