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21.
Erik HFM van der Heijden Wouter Hoefsloot Hieronymus WH van Hees Olga CJ Schuurbiers 《Respiratory research》2015,16(1)
Background
Videobronchoscopy is an essential diagnostic procedure for evaluation of the central airways and pivotal for the diagnosis and staging of lung cancer. Technological improvements have resulted in high definition (HD) images with advanced real time image enhancement techniques (i-scan).Objectives
In this study we aimed to explore the sensitivity of HD+ i-scan bronchoscopy for detection of epithelial changes like vascular abnormalities and suspicious preinvasive lesions, and tumors.Methods
In patients scheduled for a therapeutic or diagnostic procedure under general anesthesia videos of the bronchial tree were made using 5 videobronchoscopy modes in random order: normal white light videobronchoscopy (WLB), HD-bronchoscopy (HD), HD bronchoscopy with surface enhancement technique (i-scan1), HD with surface- and tone enhancement technique (i-scan2) and dual mode autofluorescence videobronchoscopy (AFB). The videos were scored in random order by two independent and blinded expert bronchoscopists.Results
In 29 patients all videos were available for analysis. Vascular abnormalities were scored most frequently in HD + i-scan2 bronchoscopy (1.33 ± 0.29 abnormal or suspicious sites per patient) as compared to 0.12 ± 0.05 site for AFB (P = 0.003). Sites suspicious for preinvasive lesions were most frequently reported using AFB (0.74 ± 0.12 sites per patient) as compared to 0.17 ± 0.06 for both WLB and HD bronchoscopy (P = 0.003). Tumors were detected equally by all modalities. The preferred modality was HD bronchoscopy with i-scan (tone- plus surface and surface enhancement in respectively 38% and 35% of cases P = 0.006).Conclusions
This study shows that high definition bronchoscopy with image enhancement technique may result in better detection of subtle vascular abnormalities in the airways. Since these abnormalities may be related to preneoplastic lesions and tumors this is of clinical relevance. Further investigations using this technique relating imaging to histology are warranted. 相似文献22.
23.
24.
J Steinbuch AC van Dijk FHBM Schreuder MTB Truijman J Hendrikse PJ Nederkoorn A van der Lugt E Hermeling APG Hoeks WH Mess 《Cardiovascular ultrasound》2017,15(1):9
Background
Mean or maximal intima-media thickness (IMT) is commonly used as surrogate endpoint in intervention studies. However, the effect of normalization by surrounding or median IMT or by diameter is unknown. In addition, it is unclear whether IMT inhomogeneity is a useful predictor beyond common wall parameters like maximal wall thickness, either absolute or normalized to IMT or lumen size. We investigated the interrelationship of common carotid artery (CCA) thickness parameters and their association with the ipsilateral internal carotid artery (ICA) stenosis degree.Methods
CCA thickness parameters were extracted by edge detection applied to ultrasound B-mode recordings of 240 patients. Degree of ICA stenosis was determined from CT angiography.Results
Normalization of maximal CCA wall thickness to median IMT leads to large variations. Higher CCA thickness parameter values are associated with a higher degree of ipsilateral ICA stenosis (p?<?0.001), though IMT inhomogeneity does not provide extra information. When the ratio of wall thickness and diameter instead of absolute maximal wall thickness is used as risk marker for having moderate ipsilateral ICA stenosis (>50%), 55 arteries (15%) are reclassified to another risk category.Conclusions
It is more reasonable to normalize maximal wall thickness to end-diastolic diameter rather than to IMT, affecting risk classification and suggesting modification of the Mannheim criteria.Trial registration
Clinical trials.gov NCT01208025.25.
A mouse genomic clone containing a lactate dehydrogenase-A (LDH-A)
processed pseudogene and a B1 repetitive element was isolated, and a
nucleotide sequence of approximately 3 kb was determined. The pseudogene
and B1 element are flanked by perfect 13-bp repeats, and the B1 sequence
starts at 14 nucleotides 3' to the presumptive polyadenylation signal of
the pseudogene. The nucleotide sequences of the LDH-A genes and processed
pseudogenes from mouse, rat, and human were compared, and a phylogenetic
tree was constructed. The rate and pattern of nucleotide substitutions in
the LDH-A pseudogenes are similar to previously reported results (Li et al.
1984). The average rate of nucleotide substitutions in the LDH-A
pseudogenes is 4.3 X 10(- 9)/site/year. The substitutions of C----T and
G----A are most frequent, and A----G substitutions are relatively high. The
rate of synonymous substitutions in the LDH-A genes is 5.3 X 10(-9), which
is not significantly higher than the average rate of 4.7 X 10(-9) for 35
mammalian genes. The rate of nonsynonymous substitutions in the LDH-A genes
is 0.20 X 10(-9), which is considerably lower than the average rate of 0.88
X 10(-9) for 35 mammalian genes. Thus, the mammalian LDH-A gene appears to
be highly conserved in evolution.
相似文献
26.
Maximum likelihood estimation of the heterogeneity of substitution rate among nucleotide sites 总被引:23,自引:9,他引:14
This paper presents a maximum likelihood approach to estimating the
variation of substitution rate among nucleotide sites. We assume that the
rate varies among sites according to an invariant+gamma distribution, which
has two parameters: the gamma parameter alpha and the proportion of
invariable sites theta. Theoretical treatments on three, four, and five
sequences have been conducted, and computer program have been developed. It
is shown that rho = (1 + theta alpha)/(1 + alpha) is a good measure for the
rate heterogeneity among sites. Extensive simulations show that (1) if the
proportion of invariable sites is negligible, i.e., theta = 0, the gamma
parameter alpha can be satisfactorily estimated, even with three sequences;
(2) if the proportion of invariable sites is not negligible, the
heterogeneity rho can still be suitably estimated with four or more
sequences; and (3) the distances estimated by the proposed method are
almost unbiased and are robust against violation of the assumption of the
invariant + gamma distribution.
相似文献
27.
A specific, saturable receptor for rabies virus was analyzed on cultured cells of neural or non-neural origin. Viral attachment kinetics were enhanced by DEAE-dextran, an effect which in turn enhanced the apparent infectivity of the virus inoculum. Under optimized conditions, the attachment of metabolically labeled ERA strain rabies virus obeyed the laws of mass action, whereby the amount of virus bound to cells varied proportionally with the concentration of cells or virus. Attachment was sensitive to changes of temperature and pH, did not require divalent cations such as Mg2+ or Ca2+, and occurred despite prior treatment of cells with proteolytic or sialic acid-specific enzymes. Saturation of the cell surface with rabies virus could be accomplished with 3 X 10(3) to 15 X 10(3) attached virions per cell. Competition for the rabies receptor occurred with rabies nonpathogenic variant virus, RV194 -2, and vesicular stomatitis virus. Reovirus type 3, another neurotropic virus, failed to inhibit rabies virus binding, and West Nile virus only slightly inhibited rabies virus binding, suggesting independent cellular receptors were recognized by these viruses. Isolated rabies virus glycoprotein failed to compete in an equivalent manner. However, solubilization of BHK-21 cells with octylglucoside yielded a chloroform-methanol-soluble extract which blocked rabies virus attachment. The binding inhibition activity of this extract was resistant to proteases but could be destroyed by phospholipases and neuraminidase, suggesting a phospholipid or glycolipid component at the receptor site. These data provide evidence for a rhabdovirus-common mechanism for cellular attachment to cells in culture. 相似文献
28.
Virus Replication in Enucleate Cells: Vesicular Stomatitis Virus and Influenza Virus 总被引:28,自引:17,他引:11 下载免费PDF全文
The requirement of the presence of a nucleus for the replication of vesicular stomatitis virus and influenza virus has been examined by following the growth and development of these viruses in enucleate BS-C-1 cells. Vesicular stomatitis virus replicates normally in enucleate cells with the rate of production of infectious virus, the amount of virus-specific protein synthesis, and the type of proteins produced being essentially the same in nucleate and enucleate cells. Influenza virus does not replicate in enucleate cells, no virus gene products can be detected, and there is no inhibition of cellular protein synthesis. 相似文献
29.
30.
Purev E Cai D Miller E Swoboda R Mayer T Klein-Szanto A Marincola FM Mick R Otvos L Wunner W Birebent B Somasundaram R Wikstrand CJ Bigner D DeMichele A Acs G Berlin JA Herlyn D 《Journal of immunology (Baltimore, Md. : 1950)》2004,173(10):6472-6480
Mutated epidermal growth factor receptor (EGF-RvIII, DeltaEGF-R, and de2-7 EGF-R) is the result of an 801-bp deletion within the extracellular domain of wild-type EGF-R and is expressed by breast carcinomas, but not by normal breast tissues. EGF-RvIII is expressed both on the surface and in the cytoplasm of tumor cells. Thus, EGF-RvIII is a potential tumor-specific target for both Abs and T cells. However, it is not known whether breast cancer patients can raise immune responses to EGF-RvIII expressed by their tumors. The demonstration of EGF-RvIII-specific immune responses in patients would suggest that immunization of patients with EGF-RvIII vaccines is feasible, because these vaccines may boost a pre-existing immune response. We have evaluated humoral and cellular immune responses to EGF-RvIII in 16 breast cancer patients and three healthy donors. Seven of 16 patients developed EGF-RvIII-specific Abs that bound to isolated EGF-RvIII protein or the protein expressed by EGF-RvIII-transfected mouse fibroblasts. The Abs that bound to EGF-RvIII did not bind to wild-type EGF-R, and anti-EGF-RvIII Abs were not found in the sera of healthy donors. Three patients had EGF-RvIII peptide-specific lymphoproliferative responses, and two of these patients also had humoral immune responses. Humoral and cellular immune responses correlated with EGF-RvIII expression by patients' tumors in most cases. These studies demonstrate that breast cancer patients specifically recognize EGF-RvIII with an overall immune response rate of 50%, suggesting that patients may benefit from vaccination against EGF-RvIII, boosting pre-existing immune responses. 相似文献