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81.
Background
Several point-of-care (POC) tests are available for evaluation of febrile patients, but the data about their performance in acute care setting is sparse. We investigated the analytical accuracy and feasibility of POC tests for white blood cell (WBC) count and C-reactive protein (CRP) at the pediatric emergency department (ED).Methods
In the first part of the study, HemoCue WBC and Afinion AS100 CRP POC analyzers were compared with laboratory’s routine WBC (Sysmex XE-2100) and CRP (Modular P) analyzers in the hospital central laboratory in 77 and 48 clinical blood samples, respectively. The POC tests were then adopted in use at the pediatric ED. In the second part of the study, we compared WBC and CRP levels measured by POC and routine methods during 171 ED patient visits by 168 febrile children and adolescents. Attending physicians performed POC tests in capillary fingerprick samples.Results
In parallel measurements in the laboratory both WBC and CRP POC analyzers showed good agreement with the reference methods. In febrile children at the emergency department (median age 2.4 years), physician performed POC determinations in capillary blood gave comparable results with those in venous blood analyzed in the laboratory. The mean difference between POC and reference test result was 1.1 E9/L (95% limits of agreement from -6.5 to 8.8 E9/L) for WBC and -1.2 mg/L (95% limits of agreement from -29.6 to 27.2 mg/L) for CRP.Conclusions
POC tests are feasible and relatively accurate methods to assess CRP level and WBC count among febrile children at the ED. 相似文献82.
Tuula Salo Marilena Vered Ibrahim O. Bello Pia Nyberg Carolina Cavalcante Bitu Ayelet Zlotogorski Hurvitz Dan Dayan 《Experimental cell research》2014
The research on oral cancer has focused mainly on the cancer cells, their genetic changes and consequent phenotypic modifications. However, it is increasingly clear that the tumor microenvironment (TME) has been shown to be in a dynamic state of inter-relations with the cancer cells. The TME contains a variety of components including the non-cancerous cells (i.e., immune cells, resident fibroblasts and angiogenic vascular cells) and the ECM milieu [including fibers (mainly collagen and fibronectin) and soluble factors (i.e., enzymes, growth factors, cytokines and chemokines)]. Thus, it is currently assumed that TME is considered a part of the cancerous tissue and the functionality of its key components constitutes the setting on which the hallmarks of the cancer cells can evolve. Therefore, in terms of controlling a malignancy, one should control the growth, invasion and spread of the cancer cells through modifications in the TME components. This mini review focuses on the TME as a diagnostic approach and reports the recent insights into the role of different TME key components [such as carcinoma-associated fibroblasts (CAFs) and inflammation (CAI) cells, angiogenesis, stromal matrix molecules and proteases] in the molecular biology of oral carcinoma. Furthermore, the impact of TME components on clinical outcomes and the concomitant need for development of new therapeutic approaches will be discussed. 相似文献
83.
Telomeres are specialized nucleoprotein complexes that provide protection to the ends of eukaryotic chromosomes. Telomeric DNA consists of tandemly repeated G-rich sequences that terminate with a 3′ single-stranded overhang, which is important for telomere extension by the telomerase enzyme. This structure, as well as most of the proteins that specifically bind double and single-stranded telomeric DNA, are conserved from yeast to humans, suggesting that the mechanisms underlying telomere identity are based on common principles. The telomeric 3′ overhang is generated by different events depending on whether the newly synthesized strand is the product of leading- or lagging-strand synthesis. Here, we review the mechanisms that regulate these processes at Saccharomyces cerevisiae and mammalian telomeres. 相似文献
84.
Rajani Sarojam Pia G. Sappl Alexander Goldshmidt Idan Efroni Sandra K. Floyd Yuval Eshed John L. Bowman 《The Plant cell》2010,22(7):2113-2130
In seed plants, leaves are born on radial shoots, but unlike shoots, they are determinate dorsiventral organs made of flat lamina. YABBY genes are found only in seed plants and in all cases studied are expressed primarily in lateral organs and in a polar manner. Despite their simple expression, Arabidopsis thaliana plants lacking all YABBY gene activities have a wide range of morphological defects in all lateral organs as well as the shoot apical meristem (SAM). Here, we show that leaves lacking all YABBY activities are initiated as dorsiventral appendages but fail to properly activate lamina programs. In particular, the activation of most CINCINNATA-class TCP genes does not commence, SAM-specific programs are reactivated, and a marginal leaf domain is not established. Altered distribution of auxin signaling and the auxin efflux carrier PIN1, highly reduced venation, initiation of multiple cotyledons, and gradual loss of the SAM accompany these defects. We suggest that YABBY functions were recruited to mold modified shoot systems into flat plant appendages by translating organ polarity into lamina-specific programs that include marginal auxin flow and activation of a maturation schedule directing determinate growth. 相似文献
85.
Martin Flajšhans David Gela Martin Kocour Hana Buchtová Marek Rodina Martin Pšenička Vojtěch Kašpar Veronika Piačková Eliška Sudová Otomar Linhart 《Reviews in Fish Biology and Fisheries》2010,20(3):317-329
Performance and physiological traits and health of spontaneous and induced triploid tench are reviewed. Triploidy is best
induced with cold shock; with triploids exhibiting 13.5–51.5% better weight gain, 2.69–3.94% higher slaughtering value, 20–60%
lower gonadosomatic index, 0.9–4.5% higher dry matter in flesh and up to 107% more flesh fat than diploids, if farmed untill
post sexual maturity. Triploids exhibit more abdominal fat and less polyunsaturated fatty acids of the n-3 and n-6 groups
in the flesh. Triploid females are sterile, while triploid males may produce aneuploid spermatozoa with varying DNA content
(1–1.9n) which may initiate development of embryos. Triploids have milder seasonal dynamics in their erythrocyte profile than
the diploids. Thinner diffusion distance in gills of triploids than in diploids is interpreted as adaptation to lower aerobic
capacity. Triploids show neither stronger tendencies to anatomic malformations, nor have bigger affinity to parasitic diseases
than the diploids. Production of triploid tench could be an economically interesting method of farming to higher marketable
weight, bringing a relatively high product quality. 相似文献
86.
Proteinase activated receptors (PAR 1-4) are membrane receptors with a unique way of activation by proteinases like thrombin, trypsin and matrix metalloproteinases which lead to a specific cellular response. To evaluate the significance of expression and co-expression of PAR in cancer we performed a survey on published data. A Pubmed literature search on “PAR, thrombin, cancer” was performed and 46 publications were selected for systematic review based on the availability of information on tumor type, material type, detection method and specification of positive cases. PAR-1 was found in 77.3% of malignant samples (n = 678), PAR-2 in 79.5% (n = 592), PAR-3 in 12.6% (n = 87) and PAR-4 in 54.9% (n = 153). PAR-1 and -2 were present in adenocarcinomas, melanomas, osteosarcomas, glioblastomas, meningiomas, leukaemias and squamous cell carcinomas. Presence of PAR-3 was limited to kidney and liver cancer. The data on PAR-4 expression was inconclusive. Those studies analysing PAR-1 and PAR-2 reported coexpression of the two receptors. PAR-1 and -2 are widely expressed in human tumors suggesting an important role in tumorigenesis and providing potential targets for therapy. PAR-3 and PAR-4 are less frequently detectable, their expression and potential role in tumorigenesis require further investigation. 相似文献
87.
88.
Hansen PS Brix TH Iachine I Sørensen TI Kyvik KO Hegedüs L 《American journal of physiology. Endocrinology and metabolism》2007,292(3):E765-E770
Serum thyrotropin (TSH), free thyroxine (T4), and free triiodothyronine (T3) levels illustrate the thyroid function set point, but the interrelations between these have never been characterized in detail. The aim of this study was to examine the associations between TSH and thyroid hormone levels in healthy euthyroid twins and to determine the extent to which the same genes influence more than one of these biochemical traits; 1,380 healthy euthyroid Danish twins (284 monozygotic, 286 dizygotic, 120 opposite-sex twin pairs) were recruited. Genetic and environmental associations between thyroid function measurements were examined using quantitative genetic modeling. In bivariate genetic models, the phenotypic relation between two measurements was divided into genetic and environmental correlations. Free T4 and free T3 levels were positively correlated (r=0.32, P<0.0001). The genetic correlation between serum free T4 and free T3 levels was rg=0.25 (95% CI 0.14-0.35), suggesting that a set of common genes affect both phenotypes (pleiotropy). The correlation between the environmental effects was re=0.41 (0.32-0.50). From this we calculated that the proportion of the correlation between free T4 and free T3 levels mediated by common genetic factors was 48%. Only 7% of the genetic component of serum free T3 levels is shared with serum free T4. Serum TSH and thyroid hormone levels did not share any genetic influences. In conclusion, thyroid hormone levels are partly genetically correlated genes that affect free T4 levels and exert pleiotropic effects on free T3 levels, although most of the genetic variance for these measurements is trait specific. 相似文献
89.
Chun-yu YIN Hong-zhou LU Wei-ming JIANG Maria Pia De Pasquale Yue-kai HU Xiao-zhang PAN Xin-hua WENG Richard T. D'Aquila Yi-Wei TANG 《Virologica Sinica》2007,22(3):212-217
Illegally paid blood donation was a risk factor for HIV acquisition exclusively in Henan and Hubei Provinces of China,and not in Shanghai.Nucleotide sequences in the gag and env genes of HIV-1 were compared between isolates from Henan and Shanghai regions of China to test whether an expected higher degree of a common source of infections from this unique blood donation transmission risk would be evident as decreased variation among Henan isolates in an exploratory cross-sectional analysis.Among 38 isolates studied,23 of 23(100%)from Henan and 8 of 15(54%)from Shanghai were subtype B.In addition,fewer sequence differences were found in gp41 of subtype B isolates from Henan than from Shanghai isolates.Further studies with additional controls are therefore warranted to confirm the role of the degree of a common source of infections in differences in HIV variation across populations. 相似文献
90.
Slc7a7 disruption causes fetal growth retardation by downregulating Igf1 in the mouse model of lysinuric protein intolerance 总被引:4,自引:0,他引:4