Active Volcanism Revealed from a Seismicity Conduit in the Long-resting Tatun Volcano Group of Northern Taiwan.

Abundant earthquakes clustered within a particular zone often reflect an active geological feature, such as clustering seismicity along a fault zone and a huge number of volcanic-earthquakes around the erupting conduit. Herein we perform a double-difference tomographic inversion and relocate the seismicity at the long-resting Tatun volcano group (TVG) in northern Taiwan. A dramatic improvement of the earthquake location model surprisingly show that, from 2014 to 2017, two clustered seismic zones are identified in the TVG. One major group of events (>1000) persistently clustered within a ~500 m diameter vertical conduit with a ~2 km height. The clustering seismicity conduit is just located nearby Dayoukeng, one of the strongest fumaroles in the TVG, and is connected to a fracture zone characterized by low Vp/Vs in the shallow crust. The other group of events is clustered within a sphere-like zone beneath Mt. Chihsin around the depths between 0.5 km and 2 km. Both seismic zones are probably triggered by the significantly volcanic gases and fluids ascending from the deep magma reservoir. Combined with a variety of results from literature, the seismicity conduit near the strong fumarole is the evidence for an active volcano and also identifies a likely pathway for ascending magma if the TVG erupts again in the future. But possibility of developing different magma pathways at other clustered seismic zones such as beneath Mt. Chihsin may not be totally excluded.

A forced running wheel system with a microcontroller that provides high-intensity exercise training in an animal ischemic stroke model

We developed a forced non-electric-shock running wheel (FNESRW) system that provides rats with high-intensity exercise training using automatic exercise training patterns that are controlled by a microcontroller. The proposed system successfully makes a breakthrough in the traditional motorized running wheel to allow rats to perform high-intensity training and to enable comparisons with the treadmill at the same exercise intensity without any electric shock. A polyvinyl chloride runway with a rough rubber surface was coated on the periphery of the wheel so as to permit automatic acceleration training, and which allowed the rats to run consistently at high speeds (30 m/min for 1 h). An animal ischemic stroke model was used to validate the proposed system. FNESRW, treadmill, control, and sham groups were studied. The FNESRW and treadmill groups underwent 3 weeks of endurance running training. After 3 weeks, the experiments of middle cerebral artery occlusion, the modified neurological severity score (mNSS), an inclined plane test, and triphenyltetrazolium chloride were performed to evaluate the effectiveness of the proposed platform. The proposed platform showed that enhancement of motor function, mNSS, and infarct volumes was significantly stronger in the FNESRW group than the control group (P<0.05) and similar to the treadmill group. The experimental data demonstrated that the proposed platform can be applied to test the benefit of exercise-preconditioning-induced neuroprotection using the animal stroke model. Additional advantages of the FNESRW system include stand-alone capability, independence of subjective human adjustment, and ease of use.

A forced running wheel system with a microcontroller that provides high-intensity exercise training in an animal ischemic stroke model.

We developed a forced non-electric-shock running wheel (FNESRW) system that provides rats with high-intensity exercise training using automatic exercise training patterns that are controlled by a microcontroller. The proposed system successfully makes a breakthrough in the traditional motorized running wheel to allow rats to perform high-intensity training and to enable comparisons with the treadmill at the same exercise intensity without any electric shock. A polyvinyl chloride runway with a rough rubber surface was coated on the periphery of the wheel so as to permit automatic acceleration training, and which allowed the rats to run consistently at high speeds (30 m/min for 1 h). An animal ischemic stroke model was used to validate the proposed system. FNESRW, treadmill, control, and sham groups were studied. The FNESRW and treadmill groups underwent 3 weeks of endurance running training. After 3 weeks, the experiments of middle cerebral artery occlusion, the modified neurological severity score (mNSS), an inclined plane test, and triphenyltetrazolium chloride were performed to evaluate the effectiveness of the proposed platform. The proposed platform showed that enhancement of motor function, mNSS, and infarct volumes was significantly stronger in the FNESRW group than the control group (P<0.05) and similar to the treadmill group. The experimental data demonstrated that the proposed platform can be applied to test the benefit of exercise-preconditioning-induced neuroprotection using the animal stroke model. Additional advantages of the FNESRW system include stand-alone capability, independence of subjective human adjustment, and ease of use.

Epigenetic modification of Nrf2 in 5-fluorouracil-resistant colon cancer cells: involvement of TET-dependent DNA demethylation.

5-Fluorouracil (5-FU) is a widely used anticancer drug for the treatment of colorectal cancer (CRC). However, resistance to 5-FU often prevents the success of chemotherapy. Nuclear factor-erythroid 2-related factor 2 (Nrf2) is a transcriptional regulator and a possible target to overcome 5-FU resistance. The present study examined epigenetic changes associated with Nrf2 induction in a human CRC cell line (SNUC5) resistant to 5-FU (SNUC5/5-FUR). Nrf2 expression, nuclear translocation, and binding to promoter were higher in SNUC5/5-FUR cells than in SNUC5 cells. The activated Nrf2 in SNUC5/5-FUR cells led to an increase in the protein expression and activity of heme oxygenase-1 (HO-1), an Nrf2-regulated gene. SNUC5/5-FUR cells produced a larger amount of reactive oxygen species (ROS) than SNUC5 cells. The siRNA- or shRNA-mediated knockdown of Nrf2 or HO-1 significantly suppressed cancer cell viability and tumor growth in vitro and in vivo, resulting in enhanced 5-FU sensitivity. Methylation-specific (MS) or real-time quantitative MS-PCR data showed hypomethylation of the Nrf2 promoter CpG islands in SNUC5/5-FUR cells compared with SNUC5 cells. Expression of the DNA demethylase ten-eleven translocation (TET) was upregulated in SNUC5/5-FUR cells. ROS generated by 5-FU upregulated TET1 expression and function, whereas antioxidant had the opposite effect. These results suggested that the mechanism underlying the acquisition of 5-FU resistance in CRC involves the upregulation of Nrf2 and HO-1 expression via epigenetic modifications of DNA demethylation.

Corrected flow time is a good indicator for preload responsiveness during living donor liver donation.

BACKGROUND: Corrected flow time (FTc) has been utilized as preload indicator in recent literature. Accurate estimation of preload status during living donor liver donation (LDLD) is important due to fluid restriction. We evaluate the effectiveness of FTc as a surrogate of preload indicator during LDLD. MATERIALS AND METHODS: Twenty-five patients undergoing LDLD were enrolled in the study. Administration of intravenous fluid was restricted before lobectomy was performed. After the organ was harvest, fluid challenge with 500 mL of Voluven (130/0.42, Fresenius, Friedberg, Germany) was performed. Stroke volume (SV) was measured with ultrasonic cardiac output monitor (USCOM; USCOM Pty, Ltd, Sydney, Australia) before and after the fluid challenge. The FTc value obtained with USCOM before fluid challenge was recorded. Fluid responsiveness was defined as an increase in SV of more than 15%. Receiver operating characteristic (ROC) curve was performed. RESULTS: The area under ROC curve was 0.9. The optimal cutoff FTc value was 340 milliseconds during LDLD. CONCLUSIONS: FTc is a noninvasive, easily obtainable, and essentially good preload indicator during LDLD.

Critical components of the pluripotency network are targets for the p300/CBP interacting protein (p/CIP) in embryonic stem cells.

p/CIP, also known as steroid receptor coactivator 3 (SRC-3)/Nuclear Receptor Coactivator 3 (NCoA3), is a transcriptional coactivator that binds liganded nuclear hormone receptors, as well as other transcription factors, and facilitates transcription through direct recruitment of accessory factors. We have found that p/CIP is highly expressed in undifferentiated mouse embryonic stem cells (mESCs) and is downregulated during differentiation. siRNA-mediated knockdown of p/CIP decreased transcript levels of Nanog, but not Oct4 or Sox2. Microarray expression analysis showed that Klf4, Tbx3, and Dax-1 are significantly downregulated in mESCs when p/CIP is knocked down. Subsequent chromatin immunoprecipitation (ChIP) analysis demonstrated that Tbx3, Klf4, and Dax-1 are direct transcriptional targets of p/CIP. Using the piggyBac transposition system, a mouse ESC line that expresses Flag-p/CIP in a doxycycline-dependent manner was generated. p/CIP overexpression increased the level of target genes and promoted the formation of undifferentiated colonies. Collectively, these results indicate that p/CIP contributes to the maintenance of ESC pluripotency through direct regulation of essential pluripotency genes. To better understand the mechanism by which p/CIP functions in ESC pluripotency, we integrated our ChIP and transcriptome data with published protein-protein interaction and promoter occupancy data to draft a p/CIP gene regulatory network. The p/CIP gene regulatory network identifies various feed-forward modules including one in which p/CIP activates members of the extended pluripotency network, demonstrating that p/CIP is a component of this extended network.

Comparing self-efficacy and self-care behaviours between outpatients with comorbid schizophrenia and type 2 diabetes and outpatients with only type 2 diabetes.

People with schizophrenia show higher-than-normal rates of type 2 diabetes mellitus (T2DM); however, research on their understanding of diabetes self-efficacy and self-care behaviours is lacking. This study compared differences in scores of self-efficacy and self-care behaviours between outpatients with comorbid schizophrenia and T2DM and outpatients with T2DM alone. Data were collected using the Diabetes Management Self-Efficacy Scale and Summary of Diabetes Self-Care Activity questionnaire. In total, 105 outpatients with schizophrenia and T2DM and 106 outpatients with T2DM returned completed questionnaires. Results of this study revealed that outpatients with schizophrenia and T2DM had significantly lower total self-efficacy and self-care scores than outpatients with only T2DM. The stepwise regression analysis revealed that self-efficacy, the haemoglobin A1C level and current smoking were significant predictors of self-care behaviours in outpatients with comorbid schizophrenia and T2DM, which explained 33.20% of the variance. These findings help mental health professionals improve patient care through a better understanding of self-care behaviours among outpatients with comorbid schizophrenia and T2DM.

Use of variability in national and regional data to estimate the prevalence of lymphangioleiomyomatosis.

BACKGROUND: Understanding the true prevalence of lymphangioleiomyomatosis (LAM) is important in estimating disease burden and targeting specific interventions. As with all rare diseases, obtaining reliable epidemiological data is difficult and requires innovative approaches. AIM: To determine the prevalence and incidence of LAM using data from patient organizations in seven countries, and to use the extent to which the prevalence of LAM varies regionally and nationally to determine whether prevalence estimates are related to health-care provision. METHODS: Numbers of women with LAM were obtained from patient groups and national databases from seven countries (n = 1001). Prevalence was calculated for regions within countries using female population figures from census data. Incidence estimates were calculated for the USA, UK and Switzerland. Regional variation in prevalence and changes in incidence over time were analysed using Poisson regression and linear regression. RESULTS: Prevalence of LAM in the seven countries ranged from 3.4 to 7.8/million women with significant variation, both between countries and between states in the USA. This variation did not relate to the number of pulmonary specialists in the region nor the percentage of population with health insurance, but suggests a large number of patients remain undiagnosed. The incidence of LAM from 2004 to 2008 ranged from 0.23 to 0.31/million women/per year in the USA, UK and Switzerland. CONCLUSION: Using this method, we have found that the prevalence of LAM is higher than that previously recorded and that many patients with LAM are undiagnosed.

Antinuclear antibody is associated with a more advanced fibrosis and lower RNA levels of hepatitis C virus in patients with chronic hepatitis C.

AIMS: Positive serum antinuclear antibody (ANA) is present in a number of patients with chronic hepatitis C virus (HCV) infection. This study aimed to evaluate the prevalence of ANA in patients with chronic hepatitis C (CHC) and to elucidate its clinical implications in virological and histological characteristics of CHC infection. METHODS: A total of 614 CHC patients were enrolled in this prospective, hospital-based study. The serum levels of aspartate aminotransferase, alanine aminotransferase and ANA, and HCV genotype, HCV RNA level, and histological activity index scores for liver histopathology, were determined. RESULTS: The prevalence of positive ANA (titre >1:40) was 35.0%. Women had a significantly higher prevalence than men (41.2 vs 31.0%; p = 0.012). Patients positive for ANA were significantly older (mean (SD), 53.7 (10.5) vs 49.7 (11.3) years; p<0.001) and had higher mean (SD) alanine aminotransferase levels (186.9 (178.8) vs 155.50 (113.5) IU/l; p<0.001) and lower mean (SD) HCV RNA levels (5.2 (0.9) vs 5.4 (1.0) log IU/ml; p = 0.048) than those without ANA. Among 447 patients undergoing liver biopsy, those positive for ANA had a significantly higher mean (SD) fibrosis score (2.0 (1.3) vs 1.5 (1.1); p<0.001) and a higher frequency of F3-4 (69/187, 36.9% vs 50/260, 19.2%; p<0.001) than those negative for ANA. Multivariate logistic regression analyses showed that advanced fibrosis, lower HCV RNA levels and age were significant factors related to positive ANA. CONCLUSION: ANA is associated with a more advanced liver fibrosis and lower serum HCV RNA level in patients with CHC.

Associations of tumour necrosis factor alpha promoter polymorphisms at position -308 and -238 with clinical characteristics of chronic hepatitis C.

The aim of this study was to investigate the association between G vs A transitions in the promoter region of the tumour necrosis factor (TNF) alpha at positions -308 (TNF308.2) and -238 (TNF238.2) and clinical features of chronic hepatitis C (CHC). These two promoter TNF-alpha variants were determined in 250 biopsy-proven CHC patients by polymerase chain reaction amplification, followed by the Restriction Fragment Length Polymorphism (RFLP) method. The distribution of -308 and -238 TNF-alpha promoter genotypes were TNF308.1/TNF308.1: 187 (74.8%), TNF308.1/TNF308.2: 57 (22.8%) and TNF308.2/TNF308.2: 6 (2.4%), respectively, and TNF238.1/TNF238.1: 247 (98.8%) and TNF238.1/TNF238.2: 3 (1.2%). The frequencies of the TNF308.2 and TNF238.2 promoter alleles were 13.8% and 0.6%. Increased TNF308.2 allele copy numbers were significantly associated with increased frequency of lower pretreatment hepatitis C virus (HCV) RNA levels (<800 000 IU/mL; P = 0.031) and severe fibrosis stage (F3-F4; P = 0.006) and higher mean fibrosis score (P = 0.007). The higher cytokine production (with one or two TNF308.2 alleles) was correlated significantly with lower pretreatment HCV RNA levels with a lower mean HCV RNA level (P = 0.024) and increased frequency of lower pretreatment HCV RNA levels (<800 000 IU/mL; P = 0.017). Stepwise logistic regression showed that higher fibrosis score and low HCV RNA levels were independently related to the TNF308.2 allele [odds ratio (95% CI): 1.385 (1.127-1.702) and 0.698 (0.488-0.990)]. We conclude that inheritance of the TNF-alpha promoter genotype at the position -308 appears to be associated with variability in severity of fibrosis and viral load in chronic HCV infection.

Viral hepatitis and proteinuria in an area endemic for hepatitis B and C infections: another chain of link?

BACKGROUND AND OBJECTIVES: Virus hepatitis may lead to nephropathy as one of its multiple extrahepatic manifestations. Proteinuria by dipstick, a simple test in practice, is a useful and cardinal sign of underlying renal abnormalities. The aim of this study was to elucidate the impact of hepatitis B virus (HBV) and/or hepatitis C virus (HCV) infections on the occurrence of proteinuria amongst adults. DESIGN AND SETTING: A prospective, cross-sectional, community-based study was conducted in an HBV/HCV endemic area of southern Taiwan. Eligible subjects aged 40-65 years (n=9934) underwent testing of hepatitis B surface antigen (HBsAg), HCV antibody (anti-HCV) and other related biochemical profiles. Urinalysis with repeated dipstick for proteinuria detection was performed. RESULTS: Anti-HCV-positive rate amongst proteinuria subjects was significantly higher than nonproteinuria subjects (9.6% vs. 6.2%, P<0.001). By contrast, HBsAg-positive rate did not differ between subjects with and without proteinuria (13.0% vs. 13.8%, P=0.57). Prevalence of proteinuria amongst anti-HCV-positive subjects (10.2%) was significantly higher than that in HBsAg-positive subjects (6.4%, P=0.004) and in HBsAg-negative or anti-HCV-negative subjects (7.0%, P=0.004). The difference persisted even after excluding diabetics. Multivariate logistic regression analyses showed that diabetes was the most important significant factor associated with proteinuria, followed by hypertension, anti-HCV seropositivity, body mass index, age and triglyceride levels. CONCLUSION: We demonstrated the significant association between proteinuria and HCV, but not HBV, infection in this HBV/HCV-endemic area.

The role of thyroid autoantibodies in the development of thyroid dysfunction in Taiwanese chronic hepatitis C patients with interferon-alpha and ribavirin combination therapy.

To investigate the role of thyroid autoantibodies in the development of thyroid dysfunction among chronic hepatitis C (CHC) patients receiving interferon-alpha (IFN-alpha) plus ribavirin (RBV) combination therapy, 95 Taiwanese naïve patients with baseline euthyroidism were enrolled. They were treated with IFN-alpha2b, 6 million units thrice weekly, plus RBV 1,000-1,200 mg daily for 24 weeks. Thyroid function, anti-thyroglobulin and antiperoxidase autoantibodies were tested at enrollment (M0), at the end-of-treatment (M6) and 6 months after end-of-treatment (M12). The percentages of thyroid autoantibodies were 8.4%, 11.6% and 9.5%, at M0, M6 and M12 respectively. Fourteen (14.7%) patients developed thyroid dysfunction at M6 or M12. Thyroid dysfunction occurred during treatment in five (62.5%) of the eight patients with baseline thyroid autoantibodies, which was significantly higher than nine (10.3%) of 87 patients without baseline thyroid autoantibodies (P = 0.0001). Among 14 patients who developed thyroid dysfunction, four (80.0%) of five patients with baseline thyroid autoantibodies recovered at M12, in contrast to two (25%) of eight without baseline thyroid autoantibodies recovered at M12 (P < 0.05). In conclusion, thyroid autoantibodies, either occurred before or during IFN-alpha plus RBV combination therapy, carry a high prediction of subsequent thyroid dysfunction. There also exists difference in the clinical manifestations of thyroid dysfunction in CHC patients treated with combination therapy.

Conservation of Pitx1 expression during amphibian limb morphogenesis.

In contrast to the pattern of limb emergence in mammals, chicks, and the newt N. viridescens, embryos such as Xenopus laevis and Eleutherodactylus coqui initiate pelvic limb buds before they develop pectoral ones. We studied the expression of Pitx1 in X. laevis and E. coqui to determine if this paired-like homeodomain transcription factor directs differentiation specifically of the hindlimb, or if it directs the second pair of limbs to form, namely the forelimbs. We also undertook to determine if embryonic expression patterns were recapitulated during the regeneration of an amputated limb bud. Pitx1 is expressed in hindlimbs in both X. laevis and E. coqui, and expression is similar in both developing and regenerating limb buds. Expression in hindlimbs is restricted to regions of proliferating mesenchyme.

Comparison of a 6-month course peginterferon alpha-2b plus ribavirin and interferon alpha-2b plus ribavirin in treating Chinese patients with chronic hepatitis C in Taiwan.

Previous studies in Caucasian patients showed treatment of chronic hepatitis C with pegylated interferon/ribavirin was well tolerated, and produced a higher response rate especially in genotype 1 infections. However, it is unknown whether this conclusion can be extrapolated to patients with Chinese ethnic origin. A total of 153 patients with biopsy-proven chronic hepatitis C were randomly assigned to receive either weekly injection of peginterferon alpha-2b 1.5 mcg/kg plus oral ribavirin (1000 or 1200 mg/day, depending on body weight) (PEG group, n = 76) or 3 MU of interferon alpha-2b t.i.w. plus ribavirin (IFN group, n = 77) for 24 weeks. Sustained virological response (SVR) was defined as the sustained disappearance of serum hepatitis C virus (HCV) RNA at 24 weeks after the end of treatment by polymerase chain reaction assay. Baseline demographic, viral and histological characteristics were comparable between the two groups. Using an intent-to-treat analysis, HCV genotype 1 patients showed a significantly higher SVR in patients receiving PEG-IFN rather than IFN (65.8%vs 41.0%, P = 0.019), but no difference was found in genotype non-1 patients (PEG vs IFN: 68.4%vs 86.8%, P = 0.060). Genotype 1 patients (28.6%) in the PEG-IFN group relapsed, as compared with 52.9% in the IFN group (P = 0.040). Multivariate analyses showed early virological response at week 12 of therapy and genotype non-1 were significant predictors to SVR. As compared with the IFN group, patients receiving PEG-IFN had a significantly higher rate of discontinuation, dose reduction, fever, headache, insomnia, leucopenia and thrombocytopenia. In genotype 1 chronic hepatitis C Chinese patient, PEG-IFNalpha2b ribavirin had significantly better SVR and lower relapse rate when compared to IFN/ribavirin. Both regimens can be recommended for genotype non-1 chronic hepatitis C Chinese patients. However, a higher rate of adverse events and discontinuance of therapy were noted in patients treated with PEG-IFNalpha2b ribavirin.

In-patient medical resource utilization for high-level cervical spinal cord injury without bone fracture in Taiwan.

STUDY DESIGN: Retrospective review of secondary data obtained from the Bureau of National Health Insurance (BNHI) on medical resource utilization in in-patient cervical spinal cord injury patients in Taiwan. OBJECTIVES: Since the start of the National Health Insurance Program in Taiwan in 1995, costs have continued to increase each year. High-level cervical spinal cord injury, a catastrophic illness, consumes a large amount of medical resources. Appropriate control of in-patient costs for these patients is mandatory. Analyses of the factors influencing the health-care costs of these patients are needed, so cost-containment policies can be established by the BNHI to conserve health-care resources. SETTING: Health-care institutions throughout Taiwan. METHODS: We obtained secondary data on a randomized basis for diagnostic codes 952.00, 952.01, 952.02, or 952.03 of the International Classification of Diseases, Ninth Revision, Clinical Modification from the BNHI files of annual in-patient expenses during the period from 1998 to 2000. There were 184 hospital admission records studied. RESULTS: The lengths of stay and in-patient costs were significantly different among different hospital types. Length of stay also was statistically different according to patient, gender, and age. The lengths of stay and in-patient costs were influenced by the hospital accreditation level and patient gender. Medical orders were influenced by patient age. CONCLUSIONS: Basic and selective diagnostics and therapeutics for high-level spinal cord injury without bone fracture should be established. Thus, patient needs for appropriate medical care will be met and overuse of medical resources will be prevented. Communication among doctors also should be strengthened.

Clinical evaluation of the COBAS Amplicor HBV monitor test for measuring serum HBV DNA and comparison with the Quantiplex branched DNA signal amplification assay in Taiwan.

AIMS: To evaluate the performance characteristics and clinical usefulness of the COBAS Amplicor HBV monitor (COBAS-AM) test in Taiwan and to examine its correlation with the Quantiplex branched DNA signal amplification (bDNA) assay for measuring serum hepatitis B virus (HBV) DNA concentrations. METHODS: HBV DNA was measured by the COBAS-AM test in 149 sera from chronic HBV infected patients that had previously been analysed by the bDNA assay. RESULTS: The COBAS-AM test showed good reproducibility, with acceptable intra-assay and interassay coefficients of variation (1.6% and 0.9%, respectively) and good linearity (r2=0.98). The overall sensitivity of the COBAS-AM test was significantly higher than that of the bDNA assay (95.3% v 83.2%): 69.6% of samples with HBV DNA below the detection limit of the bDNA assay could be measured by the COBAS-AM test. There was a significant correlation between the results of the two assays (r=0.901; p<0.0001). On average, the results derived from the COBAS-AM test were 0.55 log lower than those of the bDNA assay. HBV DNA concentrations were significantly higher among HBV e antigen (HBeAg) positive patients than negative ones, and higher among patients with abnormal alanine aminotransferase (ALT) concentrations than those with normal ALT concentrations (p=0.0003). CONCLUSIONS: The COBAS-AM assay, more sensitive in HBeAg negative samples than the bDNA assay, can effectively measure HBV DNA concentrations in Taiwanese patients. HBV DNA values measured by the COBAS-AM test and bDNA assay correlate significantly.

Multiple inflammatory pseudotumors of the spleen: case report.

The imaging findings of multiple splenic inflammatory pseudotumors in a 45-year-old male are described. Peripheral ring enhancement on arterioportal phase and gradual enhancement from the periphery to the center on venous delay phase on contrast-enhanced dynamic magnetic resonance imaging were compatible with the pathologic findings. This result may aid in the preoperative diagnosis of these benign lesions.

Influence of age on intrarenal resistive index measurement in normal subjects.

BACKGROUND: We investigated the influence of age on intrarenal arterial resistive index (RI) measurement in 135 normal subjects (71 male, 64 female; age range = 17-68 years, median age = 37 years). METHODS: Each subject underwent color Doppler measurement of the intrarenal RI from three distinct interlobar arteries in the superior, middle, and inferior parts of both kidneys. The mean of six RI values obtained from both kidneys was used for analysis. The correlation of RI with different variables was investigated by linear regression and stepwise multiple linear regression. Variables analyzed were age, systolic blood pressure, diastolic blood pressure, mean blood pressure, pulse pressure, and pulse rate. RESULTS: The results of linear regression showed that age had a significantly positive correlation ( r = 0.276, p = 0.0012) and diastolic blood pressure had a significantly negative correlation ( r = -0.186, p = 0.0311) with the RI. The results of stepwise multiple linear regression showed that the combination of age and diastolic blood pressure could explain approximately 15% of the RI changes ( r(2) = 0.1535). CONCLUSION: Although there is a statistically significant positive correlation between intrarenal RI and age, the correlation is weak. This suggests that the influence of age on RI measurement is small and may be of no clinical importance.

Voxel-based texture mapping for medical data.

In computerized image and graphic applications, texture mapping is one of the most commonly used methods to improve the realism or to enhance the visual effect of object rendering without too much increase in computational complexity. The conventional method usually has to transfer three-dimensional (3D) object to the polygonal structure, and is computationally expensive. As the medical data are mostly in voxel format, the polygonal structure is not efficient or requires more complicated mechanism in retrieving the internal information of medical data. In this paper, we propose a new texture mapping method, based on flattening a chain-coded 3D surface, to handle the voxel-based data directly. The method flattens the 3D object surface onto a two-dimensional (2D) plane and then uses 2D metamorphosis to generate the correspondences between object surface and texture image. Therefore, polygon transformation is no longer necessary and texture mapping is handled with inexpensive 2D morphing. More importantly, the internal information of medical data can be easily preserved and utilized further. Experimental results have shown the effectiveness and efficiency of the proposed algorithm.

The prevalence of TT virus and GB virus C/hepatitis G virus infection in individuals with raised liver enzymes but without HBV or HCV infection in Taiwan.

The prevalence of TT virus (TTV) and GB virus-C/hepatitis G virus (GBV-C/HGV) infection and the association with raised liver function tests in 546 Taiwanese with negative HBsAg, anti-HCV and HCV RNA was elucidated. They were tested for serum alanine aminotransferase (ALT), GBV-C/HGV RNA, anti-envelope protein 2 antibody (anti-E2) and TTV DNA. Direct sequencing and phylogenetic analyses were performed on 58 isolates for TTV genotype determination. The prevalence of TTV DNA, GBV-C/HGV RNA, anti-E2 and over all GBV-C/HGV exposure was 24.9, 3.4, 8.2 and 11.1%, respectively. Using uni- and multi-variate analyses, male gender and TTV viremia were associated significantly with raised ALT values. Sixty-nine percent of TTV isolates were deduced to be TTV genotype 1 and they had significantly lower mean age than genotype non-1 isolates. In the population, raised ALT may be related to male gender and be attributable to TTV infection but not to GBV-C/HGV among individuals with no evidence of current HBV and HCV infection. TTV genotype 1 is the most prevalent genotype and associated with younger age.