2,727 research outputs found
Adipocytokines modulate ionic currents – A key to lipotoxicity potentiated cardiac arrhythmia
Bronchioloalveolar carcinoma
AbstractBronchioloalveolar carcinoma is a subtype of adenocarcinoma of the lung with a relatively better prognosis. We reviewed the cases of 50 consecutive patients with bronchioloalveolar carcinoma treated during a 10-year period and attempted to analyze factors related to prognosis. During the 10-year study period, the prevalence of bronchioloalveolar carcinoma relative to adenocarcinoma of the lung remained steady. The subjects included 32 male and 18 female patients with mean ages of 64.7 years and 55.1 years, respectively (p = 0.0030). The preoperative radiographic findings included 40 cases of localized and 10 cases of diffuse bronchioloalveolar carcinoma. The clinicopathologic TNM staging included 20 patients with stage I cancer, 4 with stage II cancer, 11 with stage IIIa cancer, 3 with stage IIIb cancer, and 12 with stage IV cancer. Forty patients with clinical stage I, II, or III disease underwent operation (operability 80%). The resectability rate was 90% (36 of 40). Thirty-four procedures were considered as curative. The overall cumulative survival at 5 years was 22.2% (46.4% for stage I). Different TNM stages showed significant differences in survival time (p = 0.0001). The median survival times were 64.6 months for stage I, 48.0 months for stage II, 24.7 months for stage IIIa, 9.0 months for stage IIIb, and 4.5 months for stage IV disease. The median survival time for localized bronchioloalveolar carcinoma was 27.5 months, and the median survival time for diffuse bronchioloalveolar carcinoma was 4.3 months (p = 0.0002). The median survival time for the curative resection group was 30.6 months, and the median survival time for the noncurative resection or nonresection group was 5.8 months (p = 0.0001). On the basis of this study we conclude that (1) the prevalence of bronchioloalveolar carcinoma is quite steady, (2) bronchioloalveolar carcinoma presents at an earlier age in women, (3) bronchioloalveolar carcinoma frequently presents with lymphatic spread or systemic metastasis at diagnosis, (4) most localized bronchioloalveolar carcinomas are resectable and the prognosis with this type is better than that of the diffuse type, and (5) long-term survival correlates closely with initial roentgenographic appearance, TNM stage, and completeness of surgical resection. (J THORAC CARDIOVASC SURG 1995;110:374-81
An Image Retrieval System Based on the Color Complexity of Images
The fuzzy color histogram (FCH) spreads each pixel's total membership value to all histogram bins based on their color similarity. The FCH is insensitive to quantization errors. However, the FCH can state only the global properties of an image rather than the local properties. For example, it cannot depict the color complexity of an image. To characterize the color complexity of an image, this paper presents two image features -- the color variances among adjacent segments (CVAAS) and the color variances of the pixels within an identical segment (CVPWIS). Both features can explain not only the color complexity but also the principal pixel colors of an image. Experimental results show that the CVAAS and CVPWIS based image retrieval systems can provide a high accuracy rate for finding out the database images that satisfy the users' requirement. Moreover, both systems can also resist the scale variances of images as well as the shift and rotation variances of segments in images
Determining Optimal Wireless Propagation Model for a Region and Wavelength
Generally, the present disclosure is directed to determining an optimal wireless propagation model for a given region and wavelength. In particular, in some implementations, the systems and methods of the present disclosure can include or otherwise leverage one or more machine-learned models to predict an optimal wireless propagation model for a region based on terrain data for the region
Machine-Learned Wireless Propagation Model
Generally, the present disclosure is directed to predicting wireless propagation in an area and/or at a wavelength. In particular, in some implementations, the systems and methods of the present disclosure can include or otherwise leverage one or more machine-learned models to predict propagation data (e.g. radio signal attenuation and/or Bit Error Rate (BER)) based on connection data and terrain data
Differentially profiling the low-expression transcriptomes of human hepatoma using a novel SSH/microarray approach
BACKGROUND: The main limitation in performing genome-wide gene-expression profiling is the assay of low-expression genes. Approaches with high throughput and high sensitivity for assaying low-expression transcripts are urgently needed for functional genomic studies. Combination of the suppressive subtractive hybridization (SSH) and cDNA microarray techniques using the subtracted cDNA clones as probes printed on chips has greatly improved the efficiency for fishing out the differentially expressed clones and has been used before. However, it remains tedious and inefficient sequencing works for identifying genes including the great number of redundancy in the subtracted amplicons, and sacrifices the original advantages of high sensitivity of SSH in profiling low-expression transcriptomes. RESULTS: We modified the previous combination of SSH and microarray methods by directly using the subtracted amplicons as targets to hybridize the pre-made cDNA microarrays (named as "SSH/microarray"). mRNA prepared from three pairs of hepatoma and non-hepatoma liver tissues was subjected to the SSH/microarray assays, as well as directly to regular cDNA microarray assays for comparison. As compared to the original SSH and microarray combination assays, the modified SSH/microarray assays allowed for much easier inspection of the subtraction efficiency and identification of genes in the subtracted amplicons without tedious and inefficient sequencing work. On the other hand, 5015 of the 9376 genes originally filtered out by the regular cDNA microarray assays because of low expression became analyzable by the SSH/microarray assays. Moreover, the SSH/microarray assays detected about ten times more (701 vs. 69) HCC differentially expressed genes (at least a two-fold difference and P < 0.01), particularly for those with rare transcripts, than did the regular cDNA microarray assays. The differential expression was validated in 9 randomly selected genes in 18 pairs of hepatoma/non-hepatoma liver tissues using quantitative RT-PCR. The SSH/microarray approaches resulted in identifying many differentially expressed genes implicated in the regulation of cell cycle, cell death, signal transduction and cell morphogenesis, suggesting the involvement of multi-biological processes in hepato-carcinogenesis. CONCLUSION: The modified SSH/microarray approach is a simple but high-sensitive and high-efficient tool for differentially profiling the low-expression transcriptomes. It is most adequate for applying to functional genomic studies
Integrin-mediated membrane blebbing is dependent on the NHE1 and NCX1 activities.
Integrin-mediated signal transduction and membrane blebbing have been well studied to modulate cell adhesion, spreading and migration^1-6^. However, the relationship between membrane blebbing and integrin signaling has not been explored. Here we show that integrin-ligand interaction induces membrane blebbing and membrane permeability change. We found that sodium-proton exchanger 1 (NHE1) and sodium-calcium exchanger 1 (NCX1) are located in the membrane blebbing sites and inhibition of NHE1 disrupts membrane blebbing and decreases membrane permeability change. However, inhibition of NCX1 enhances cell blebbing to cause cell swelling which is correlated with an intracellular sodium accumulation induced by NHE17. These data suggest that sodium influx induced by NHE1 is a driving force for membrane blebbing growth, while sodium efflux induced by NCX1 in a reverse mode causes membrane blebbing retraction. Together, these data reveal a novel function of NHE1 and NCX1 in membrane permeability change and blebbing and provide the link for integrin signaling and membrane blebbing
Nitroprusside modulates pulmonary vein arrhythmogenic activity
<p>Abstract</p> <p>Background</p> <p>Pulmonary veins (PVs) are the most important sources of ectopic beats with the initiation of paroxysmal atrial fibrillation, or the foci of ectopic atrial tachycardia and focal atrial fibrillation. Elimination of nitric oxide (NO) enhances cardiac triggered activity, and NO can decrease PV arrhythmogensis through mechano-electrical feedback. However, it is not clear whether NO may have direct electrophysiological effects on PV cardiomyocytes. This study is aimed to study the effects of nitroprusside (NO donor), on the ionic currents and arrhythmogenic activity of single cardiomyocytes from the PVs.</p> <p>Methods</p> <p>Single PV cardiomyocytes were isolated from the canine PVs. The action potential and ionic currents were investigated in isolated single canine PV cardiomyocytes before and after sodium nitroprusside (80 μM,) using the whole-cell patch clamp technique.</p> <p>Results</p> <p>Nitroprusside decreased PV cardiomyocytes spontaneous beating rates from 1.7 ± 0.3 Hz to 0.5 ± 0.4 Hz in 9 cells (P < 0.05); suppressed delayed afterdepolarization in 4 (80%) of 5 PV cardiomyocytes. Nitroprusside inhibited L-type calcium currents, transient outward currents and transient inward current, but increased delayed rectified potassium currents.</p> <p>Conclusion</p> <p>Nitroprusside regulates the electrical activity of PV cardiomyocytes, which suggests that NO may play a role in PV arrhythmogenesis.</p
- …