High-dose dual therapy is superior to standard first-line or rescue therapy for Helicobacter pylori infection.

BACKGROUND & AIMS: The efficacy of treatment of Helicobacter pylori infection has decreased steadily because of increasing resistance to clarithromycin, metronidazole, and levofloxacin. Resistance to amoxicillin is generally low, and high intragastric pH increases the efficacy of amoxicillin, so we investigated whether a combination of a high-dose proton pump inhibitor and amoxicillin (dual therapy) was more effective than standard first-line or rescue therapies in eradicating H pylori. METHODS: We performed a large-scale multihospital trial to compare the efficacy of a high-dose dual therapy (HDDT) with that of standard therapies in treatment-naive (n = 450) or treatment-experienced (n = 168) patients with H pylori infection. Treatment-naive patients were randomly assigned to groups given HDDT (rabeprazole 20 mg and amoxicillin 750 mg, 4 times/day for 14 days, group A1), sequential therapy for 10 days (group B1), or clarithromycin-containing triple therapy for 7 days (group C1). Treatment-experienced patients were randomly assigned to groups given HDDT for 14 days (group A2), sequential therapy for 10 days (B2), or levofloxacin-containing triple therapy for 7 days (C2). H pylori infection was detected by using the (13)C-urea breath test. We evaluated factors associated with treatment outcomes. RESULTS: In the intention-to-treat analysis, H pylori was eradicated in 95.3% of patients in group A1 (95% confidence interval [CI], 91.9%-98.8%), 85.3% in B1 (95% CI, 79.6%-91.1%), and 80.7% in group C1 (95% CI, 74.3%-87.1%). Infection was eradicated in 89.3% of patients in group A2 (95% CI, 80.9%-97.6%), 51.8% in group B2 (95% CI, 38.3%-65.3%), and 78.6% (95% CI, 67.5%-89.7%) in group C2. The efficacy of HDDT was significantly higher than that of currently recommended regimens, irrespective of CYP2C19 genotype. Bacterial resistance to drugs was associated with treatment failure. There were no significant differences between groups in adverse events or patient adherence. CONCLUSIONS: HDDT is superior to standard regimens as empirical first-line or rescue therapy for H pylori infection, with similar safety profiles and tolerability. ClinicalTrials.gov number: NCT01163435.

Prediction of fatty liver disease using machine learning algorithms.

BACKGROUND AND OBJECTIVE: Fatty liver disease (FLD) is a common clinical complication; it is associated with high morbidity and mortality. However, an early prediction of FLD patients provides an opportunity to make an appropriate strategy for prevention, early diagnosis and treatment. We aimed to develop a machine learning model to predict FLD that could assist physicians in classifying high-risk patients and make a novel diagnosis, prevent and manage FLD. METHODS: We included all patients who had an initial fatty liver screening at the New Taipei City Hospital between 1st and 31st December 2009. Classification models such as random forest (RF), Naïve Bayes (NB), artificial neural networks (ANN), and logistic regression (LR) were developed to predict FLD. The area under the receiver operating characteristic curve (ROC) was used to evaluate performances among the four models. RESULTS: A total of 577 patients were included in this study; of those 377 patients had fatty liver. The area under the receiver operating characteristic (AUROC) of RF, NB, ANN, and LR with 10 fold-cross validation was 0.925, 0.888, 0.895, and 0.854 respectively. Additionally, The accuracy of RF, NB, ANN, and LR 87.48, 82.65, 81.85, and 76.96%. CONCLUSION: In this study, we developed and compared the four classification models to predict fatty liver disease accurately. However, the random forest model showed higher performance than other classification models. Implementation of a random forest model in the clinical setting could help physicians to stratify fatty liver patients for primary prevention, surveillance, early treatment, and management.

Removal of cesium ions from aqueous solution by adsorption onto local Taiwan laterite.

Utilization of local Taiwan laterite (LTL) to remove aqueous cesium was investigated in this work under the conditions of various contact time, cesium (Cs) loading and temperature. Experimental results show that adsorption is instantaneous. Freundlich and Langmuir simulation results demonstrate that local Taiwan laterite has high affinity and sorption capacity for Cs at low temperatures, which may be attributed to enhanced desorption as temperature increased. Thermodynamic parameters including DeltaH, DeltaG and DeltaS were calculated and it is indicated that Cs adsorption on LTL is an exothermic, spontaneous and physical adsorption reaction. Moreover, the adsorbed Cs is distributed evenly on the LTL surface, which is confirmed by SEM/EDS mapping images. Furthermore, the absence of apparent shifting or broadening of the kaolinite signal in XRD patterns after Cs adsorption is an indication of the non-expanding characteristic of kaolinite structure.

Long-term follow-up of hepatic hemangiomas by ultrasonography: with emphasis on the growth rate of the tumor.

BACKGROUND/AIMS: It is not rare to find hepatic hemangiomas in people in Taiwan where hepatitis B is endemic during ultrasonographic examinations for the screening of hepatocellular carcinoma, and we can therefore monitor these hemangiomas longitudinally since detected. METHODOLOGY: Totally 180 hepatic hemangiomas in 130 adult patients were followed up for more than 5 years with at least twice ultrasound examinations in our hospital. The diagnosis of hemangiomas was made by typical ultrasonographic findings as well as compatible findings in other imaging modalities. The largest diameter of the same tumor at various examinations was compared in each patient. The doubling time of tumor volume was calculated for the enlarging hepatic hemangiomas. RESULTS: The diameters of the 180 hemangiomas ranged from <8 cm - >4 cm in 11 (6.1%), < or =4 cm - >2 cm in 55 (30.6%), and < or =2 cm in 114 (63.3%). Among them, the diameter of 14 (7.7%) hemangiomas in 13 patients increased. The tumor volume doubling time of these hemangiomas ranged from 17.3 to 178.1 months. CONCLUSIONS: Although hepatic hemangiomas are benign, some of them indeed grow slowly. The growth rates of these hemangiomas varied and were definitely slower as compared with those of malignant hepatic tumors.

Liver steatosis classification using high-frequency ultrasound.

High-frequency B-mode images of 19 fresh human liver samples were obtained to evaluate their usefulness in determining the steatosis grade. The images were acquired by a mechanically controlled single-crystal probe at 25 MHz. Image features derived from gray-level concurrence and nonseparable wavelet transform were extracted to classify steatosis grade using a classifier known as the support vector machine. A subsequent histologic examination of each liver sample graded the steatosis from 0 to 3. The four grades were then combined into two, three and four classes. The classification results were correlated with histology. The best classification accuracies of the two, three and four classes were 90.5%, 85.8% and 82.6%, respectively, which were markedly better than those at 7 MHz. These results indicate that liver steatosis can be more accurately characterized using high-frequency B-mode ultrasound. Limitations and their potential solutions of applying high-frequency ultrasound to liver imaging are also discussed.

Liver fibrosis grade classification with B-mode ultrasound.

B-mode images of 20 fresh postsurgical human liver samples were obtained to evaluate ultrasound ability in determining the grade of liver fibrosis. Image features derived from gray level concurrence and nonseparable wavelet transform were extracted to classify fibrosis with a classifier known as the support vector machine. Each liver sample subsequently underwent histologic examination and liver fibrosis was graded from 0 to 5 (i.e., six grades total). The six grades were then combined into two, three, four and six classes. Classifications with the extracted image features by the support vector machine were tested and correlated with histology. The results revealed that the best classification accuracy of two, three, four and six classes were 91%, 85%, 81% and 72%, respectively. Thus, liver fibrosis can be noninvasively characterized with B-mode ultrasound, even though the performance declines as the number of classes increases. The elastic constants of 16 samples out of a total of 20 were also correlated with the image features. The Pearson correlation coefficients indicated that the image features are more strongly correlated with the fibrosis grade than with the elastic constant.

Elastic modulus measurements of human liver and correlation with pathology.

Viral hepatitis causes fibrosis in the liver and may change mechanical properties of the liver. To evaluate the impact of fibrosis on elastic properties of human liver and to investigate potential benefits of ultrasonic elasticity imaging, 19 fresh human liver samples and 1 hepatic tumor (focal nodular hyperplasia) sample obtained during operations were studied. Simple 1-D estimates based on the cyclic compression-relaxation method were performed. Elastic modulus values were derived from the predetermined strain (controlled by a step motor system) and the stress values (measured by an electronic balance). Each specimen subsequently received histologic examination and a grade of liver fibrosis was scored from 0 to 5. Results show that the elastic modulus values were on the order of several hundreds to thousands of Pascals. The elastic modulus generally increased with the fibrosis grade, although some discrepancies existed at the middle grades of fibrosis (scores 1 to 3). The correlation between the fibrosis score and the elastic modulus was significant (p < 0.01) based on the statistical analysis using the Pearson correlation method. In addition, the relation between the elastic modulus and the fibrosis grade generally exhibited a quadratic trend. It was concluded that severity of fibrosis had a good correlation with stiffness of the liver. Results also indicated that the elasticity imaging of the liver may provide significant clinical values if the elastic modulus can be accurately measured.

Characterization of malignant focal liver lesions with contrast-enhanced 40 MHz ultrasound imaging in hepatitis B virus X transgenic mice: a feasibility study.

Contrast-enhanced ultrasound (CEUS) imaging has been a reliable clinical method of detecting three vascular contrast phases and characterizing focal liver lesions. Previous results were all from human (i.e., clinical studies). The main purpose of this study was to extend this to small animals and to investigate the feasibility of using CEUS in preclinical research. Specifically, high-frequency (40 MHz) ultrasound liver imaging with albumin-shelled microbubbles was employed to detect the three vascular contrast phases and characterize focal liver lesions that developed in thirteen Hepatitis B virus X (HBx) transgenic mice at around 14 to 16 months of age. Previous studies indicated that 90-100% incidence of hepatocellular carcinoma (HCC) was observed in HBx transgenic male mice. After injecting the contrast agent, the time-intensity curves (TICs) of focal liver lesions, vessels in focal liver lesions and surrounding liver parenchyma tissues were measured for 30 minutes. The peak of mean intensity relative to the baseline increased 7.36 dB (p < 0.02). On the other hand, the mean contrast between the focal liver lesion and the liver parenchyma increased by 7.74 (p < 0.05) dB, thus allowing clear detection ofthe lesion margin. Histopathology investigations confirmed the development of the lesion in these mice. In addition, guidelines of European Federation of Societies for Ultrasound in Medicine and Biology were followed as an attempt to characterize features of the TICs in mice. The arterial phase was defined as 2 to 60 seconds post contrast injection, and the parenchyma phase was defined as the time period from 10 to 30 minutes post contrast injection. Comparing the imaging with the pathology results, the sensitivity, specificity and accuracy of CEUS for the detection of malignant focal liver lesion in HBx transgenic mice were 91%, 100% and 92%. These results demonstrated that high-frequency CEUS imaging potentially can be used for detecting the three vascular contrast phases of malignant focal liver lesions and characterizing malignant focal liver lesions in mice. Thus can be a valuable tool in preclinical research.

Tissue motion and elevational speckle decorrelation in freehand 3D ultrasound.

3D positioning is essential for quantitative volume analysis in 3D ultrasound. Particularly for freehand scanning without an external positioning device, such information must be estimated by analyzing the original 2D images prior to 3D reconstruction. Previous work on freehand 3D positioning has focused on elevational displacement estimation using speckle decorrelation for linear scans. However, the effects of other types of motion have been ignored. Given that all types of motion potentially introduce speckle decorrelation, the accuracy of the elevational displacement estimation is likely to be diminished by the presence of motions of other types. In the present study, simulations were performed to probe the effects of various motions on elevational displacement estimation. In particular, the effects of rotational motions on image correlation are investigated in detail. It is found that these motions significantly affect the estimation results and thus should be taken into account when reconstructing the 3D image. In addition, speckle variations also affect the estimation even when only elevational motion is present. Finally, full motion analysis in freehand scanning may not be possible by only using speckle correlation analysis unless speckle variations can be reduced and the correlation distribution under complex motion can be obtained.