[A study of the clinical curative effect of nucleos(t)ide analogues treated to pegylated interferon-α add-on therapy in patients with chronic hepatitis B]

Objective: To investigate the hepatitis B surface antigen (HBsAg) clearance condition and its predictive factors after treatment with nucleos(t)ide analogues to pegylated interferon-α add-on therapy in patients with chronic hepatitis B. Methods: Patients with chronic hepatitis B who visited the First Affiliated Hospital of Zhengzhou University from 2018~2019 were prospectively enrolled. HBsAg≤ 1500 IU/mL, hepatitis B e antigen-negative, HBV DNA undetectable, received antiviral treatment with nucleos(t)ide analogues for at least one year, and pegylated interferon-α add-on therapy for 48 weeks were included. The primary endpoint of study was to determine the proportion of HBsAg clearance at 72 weeks. Concurrently, the predictive factors for HBsAg clearance were analyzed. Quantitative and qualitative data were analyzed using a t-test or non-parametric test and a Fisher's exact test. Results: A total of 38 cases were included in this study, of which 13 cases obtained HBsAg clearance at 48 weeks of therapy and another six cases obtained HBsAg clearance throughout the extended treatment period of 72 weeks, accounting for 50.00% of all enrolled patients. There was a significant difference in HBsAg dynamics between the HBsAg clearance group and the non-clearance group (P < 0.05). Univariate logistic regression analysis showed that patients' age, baseline, 12-and 24-week HBsAg levels, and early HBsAg reduction were predictive factors for HBsAg clearance at 72 weeks of treatment. Multivariate logistic regression analysis showed that age (OR = 1.311; P = 0.016; 95% confidence interval: 1.051~1.635) and HBsAg levels at 24 weeks of treatment (OR = 4.481; P = 0.004; 95% confidence interval: 1.634~12.290) were independent predictors for HBsAg clearance. Conclusion: Hepatitis B e antigen-negative, nucleos(t)ide analogue treated, HBsAg ≤ 1500 IU/mL, and HBV DNA undetectable, peg-IFNα add-on treatment for 48 weeks could promote HBsAg clearance in patients with chronic hepatitis B. Six of the sixteen cases (37.50%) who did not obtain HBsAg clearance at week 48 did so with the course of therapy extended to week 72. Hence, the optimal individualized treatment strategy should be customized according to the predictors rather than the fixed 48-week course. Age (≤ 38), baseline HBsAg level (≤2.86 log(10)IU/ml), HBsAg level at 24 weeks (≤ 0.92 log(10)IU/ml), and 12-week HBsAg decrease from baseline (≥ 0.67 log(10)IU/ml) indicate that patients are highly likely to obtain HBsAg clearance at the 72 weeks of combination therapy, in which the combined indicator based on HBsAg level ≤0.92 log(10)IU/ml at 24 weeks will identify 85.0% to 100.0% of patients with HBsAg clearance.

Engineered phage with cell-penetrating peptides for intracellular bacterial infections

IMPORTANCE

Salmonella infection is a significant threat to global public health, and the increasing prevalence of antibiotic resistance exacerbates the situation. Therefore, finding new and effective ways to combat this pathogen is essential. Phages are natural predators of bacteria and can be used as an alternative to antibiotics to kill specific bacteria, including drug-resistant strains. One significant limitation of using phages as antimicrobial agents is their low cellular uptake, which limits their effectiveness against intracellular bacterial infections. Therefore, finding ways to enhance phage uptake is crucial. Our study provides a straightforward strategy for displaying cell-penetrating peptides on non-model phages, offering a promising novel and effective therapeutic approach for treating intracellular and drug-resistant bacteria. This approach has the potential to address the global challenge of antibiotic resistance and improve public health outcomes.

Longitudinal Predictive Control for Vehicle-Following Collision Avoidance in Autonomous Driving Considering Distance and Acceleration Compensation

In response to the widespread adoption of vehicle-following systems in autonomous applications, the demand for collision warning to enable safer functionalities is increasing. This study provides an approach for automated vehicle guidance to follow the preceding vehicles longitudinally and puts emphasis on the performance of collision avoidance. The safety distance model is established, which contains a distance compensation algorithm to deal with the special case on curved roads. By introducing the algorithm of velocity and distance prediction, the collision risks are detected and measured in real time. The objective function is established based on optimal control theory to solve the desired following acceleration. The control system designed with the method of proportion integration differentiation combines throttle percentage and brake pressure as outputs to compensate acceleration. In the Carsim and Simulink co-simulation platform, the control system for longitudinal collision avoidance is simulated and analysed for four typical working conditions: the preceding vehicle drives at a constant speed on straight and curved roads, while the preceding vehicle drives at various speeds on straight and curved roads. The results validate the feasibility and effectiveness of the proposed method, which can be used for the longitudinal control of vehicle-following active collision avoidance.

[Changes of GSH-PX activity and γ-GCS mRNA expression in serum of workers exposed to manganese]

Objective: To explore the changes of γ-GCS mRNA expression and GSH-PX in serum of workers exposed to manganese in order to provide scientific basis for early diagnosis of manganese poisoning. Methods: In June 2017, a total of 180 workers from a motorcycle manufacturer were selected by stratified random sampling, including 115 welders as the exposure group and 65 administrative office workers as the Control Group, the exposure group was divided into high exposure group (43 persons) and low exposure group (72 persons) according to whether the exposure group exceeded the standard limit. The levels of γ-gcs Mrna expression and GSH-Px activity in serum were determined by Occupational Health Survey, and the differences of γ-gcs Mrna expression and GSH-Px activity among different groups were analyzed. Results: Compared with the control group, the serum GSH-Px activity was lower and the serum γ-GCS mRNA expression level was higher in the exposed group (F=370.52, 275.95, P<0.01) . Compared with the control group, there was significant difference in γ-GCS mRNA expression level and GSH-Px activity (F=0.475、1.06, P<0.01; F=48.53、111.70, P<0.01) . The concentrations of manganese in air, welding dust and urine were positively correlated with the level of γ-GCS mRNA (r=0.71, 0.50, 0.31, P<0.01) The serum GSH-Px activity was negatively correlated with the concentrations of manganese in air, welding dust and urine (r=-0.80, -0.52, -0.30, P< 0.01) , There was no correlation between Serum γ-GSH-Px activity and age and years of exposure (P>0.05) . Conclusion: Serum γ-GCS mRNA expression level and GSH-Px activity level can be used as early biomarkers of manganese poisoning. The concentrations of manganese in workplace air, welding dust and urine manganese in workers are the influencing factors.

[Study on the difference of curative effect of conventional mercury displacement treatment on mercury in brain and kidney]

Objective: To explore the expulsion effect of sodium dimercaptopropanesulfonate (DMPS) on mercury in different organs of mercury poisoning and the therapeutic effect of glutathione (GSH) combined with antioxidant therapy on mercury poisoning. Methods: In February 2019, 50 SPF male SD rats were randomly divided into 5 groups, 10 rats in each group: A (saline negative control group) , B (HgCL2 positive control group) , treatment group (C: intramuscular injection of DMPS 15 mg/kg treatment, D: intramuscular injection of DMPS30 mg/kg treatment, E: intramuscular injection of DMPS 15 mg/kg and intraperitoneal injection of GSH200 mg/kg treatment) . Rats in group B, C, D and E were subcutaneously injected with mercury chloride solution (1 mg/kg) to establish a rat model of subacute mercury poisoning kidney injury. Rats in group A were subcutaneously injected with normal saline. After the establishment of the model, rats in the treatment group were injected with DMPS and GSH. Rats in group A and group B were injected with normal saline. At 21 d (treatment 7 d) and 28 d (treatment 14 d) after exposure, urine and blood samples of 5 rats in each group were collected. Blood biochemistry, urine mercury, urine microalbumin and mercury content in renal cortex, cerebral cortex and cerebellum were detected. Results: After exposure to mercury, the contents of mercury in renal cortex, cerebrum and cerebellum of rats in group B, C, D and E increased, and urine microalbumin increased. Pathology showed renal tubular injury and renal interstitial inflammation. Compared with group B, urinary mercury and renal cortex mercury in group C, D and E decreased rapidly after DMPS treatment, and there was no significant decrease in mercury levels in cerebellum and cerebral cortex of rats, accompanied by transient increase in urinary albumin after DMPS treatment (P<0.05) ; the renal interstitial inflammation in group E was improved after GSH treatment. There was a positive correlation between urinary mercury and the contents of mercury in renal cortex, cerebral cortex and cerebellum (r=0.61, 0.47, 0.48, P<0.05) . Conclusion: DMPS mercury expulsion treatment can significantly reduce the level of metal mercury in the kidney, and there is no significant change in the level of metal mercury in the cortex and cerebellum.

Deep-Neural-Network-Based Modelling of Longitudinal-Lateral Dynamics to Predict the Vehicle States for Autonomous Driving

Multibody models built in commercial software packages, e.g., ADAMS, can be used for accurate vehicle dynamics, but computational efficiency and numerical stability are very challenging in complex driving environments. These issues can be addressed by using data-driven models, owing to their robust generalization and computational speed. In this study, we develop a deep neural network (DNN) based model to predict longitudinal-lateral dynamics of an autonomous vehicle. Dynamic simulations of the autonomous vehicle are performed based on a semirecursive multibody method for data acquisition. The data are used to train and test the DNN model. The DNN inputs include the torque applied on wheels and the vehicle’s initial speed that imitates a double lane change maneuver. The DNN outputs include the longitudinal driving distance, the lateral driving distance, the final longitudinal velocities, the final lateral velocities, and the yaw angle. The predicted vehicle states based on the DNN model are compared with the multibody model results. The accuracy of the DNN model is investigated in detail in terms of error functions. The DNN model is verified within the framework of a commercial software package CarSim. The results demonstrate that the DNN model predicts accurate vehicle states in real time. It can be used for real-time simulation and preview control in autonomous vehicles for enhanced transportation safety.

[Association between CD137 and ischemia-reperfusion injury in patients with acute ST-segment elevation myocardial infarction]

Objective: To explore the relationship between the levels of serum soluble CD137 (sCD137) and membrane-bound CD137 (mCD137) and the occurrence of ischemia reperfusion injury (IRI) in patients with acute ST-segment elevation myocardial infarction (STEMI). Methods: This is a cross-sectional study. Consecutive patients with acute STEMI, who underwent emergency percutaneous coronary intervention (PCI) in the Department of Cardiology, Jiangsu University Affiliated Hospital from May 2019 to September 2020, were enrolled. According to the absence or presence of IRI, patients were divided into IRI group and non-IRI group. Clinical data of the two groups were collected and compared. sCD137 level was detected by enzyme linked immunosorbent assay. Ficoll density gradient centrifugation was used to separate peripheral blood mononuclear cells (PBMC) and RNA was extracted, mCD137 mRNA expression level was detected by PCR. Serum sCD137 levels and the mCD137 mRNA levels of PBMC before, after PCI and 24 hours after PCI were compared. The correlation between serum sCD137 level, PBMC mCD137 mRNA level and clinical indicators was observed. The univariate and multivariate logistic binary regression analyses were performed to evaluate the related risk factors of IRI. ROC curve was used to analyze the predictive value of defined parameters for IRI. Results: A total of 112 STEMI patients were enrolled. There were 42 cases (of which 33 were males (78.6%), mean age was (58.6±12.7) years) in non-IRI group and 70 cases(of which 56 were males (80.0%), mean age was (64.5±11.6) years) in IRI group. Compared with the non-IRI group, patients in the IRI group had longer hospital stays, older age, lower rates of obesity, lower systolic and diastolic blood pressure at admission, higher proportion of the the right coronary artery as culprit vessel, lower rate of the use of angiotensin-converting enzyme inhibitor/angiotensin-Ⅱ receptor blocker/angiotensin receptor neprilysin inhibitor, higher levels of urea nitrogen and creatinine, lower glomerular filtration rate, lower triglycerides, higher D-dimer and B-type natriuretic peptide_max, higher proportion of Killip grade Ⅳ and cardiovascular adverse events (all P<0.05). sCD137 levels at the preoperative, postoperative and 24 hours after surgery were significantly higher in the IRI group than in the non-IRI group, while the mRNA levels of CD137 was similar between the two groups. The level of sCD137 in patients after PCI was lower than that before operation, the level of mCD137 mRNA was higher than that before operation (P<0.05). Serum sCD137 levels were positively correlated with hospitalization days, age, B-type natriuretic peptide, creatinine, ischemic time, C Reactive protein (CRP) and CRP/albumin (P<0.05), and negatively correlated with body mass index, glomerular filtration rate and albumin (P<0.05). The mCD137 mRNA expression level of PBMC was positively correlated with hospital stay, age, B-type natriuretic peptide, ischemic time, CRP and CRP/albumin (P<0.05), and negatively correlated with body mass index, glomerular filtration rate, albumin (P<0.05). Multivariate logistic regression analysis showed that higher sCD137 (OR=1.038, 95%CI: 1.009-1.069), aspartate aminotransferase, (OR=1.029, 95%CI: 1.009-1.050) and lower albumin (OR=0.829, 95%CI: 0.703-0.829) before surgery were independent risk factors of IRI (P<0.05). Receiver operating characteristic curve showed that the area under the curve of sCD137 was 0.672 (95%CI: 0.574-0.770, P=0.002) for the prediction of IRI, the best cut-off value was 28.43×10^-3 μg/L with sensitivity of 95.2% and specificity of 48.6%. Conclusion: The significantly increased level of sCD137 in acute STEMI patients is positively correlated with reperfusion injury, which is an independent risk factor of IRI and may be related to the prognosis of patients with IRI.

[Trend analysis and prediction of colorectal cancer morbidity and mortality of residents in urban areas of Guangzhou from 1972 to 2015]

Objective: To analyze the trend of mortality and incidence of colorectal cancer among urban residents in Guangzhou from 1972 to 2015 and to predict the mortality of colorectal cancer from 2016 to 2025. Methods: The mortality data of colorectal cancer among urban residents in Guangzhou were collected from the death registration of malignant tumors of Guangzhou Health Statistics Bureau (1972-1979), Guangzhou Health Statistics (1980-2001), Guangzhou Cancer Registration Annual Report (2002-2009) and China Cancer Registration Annual Report (2010-2015). The incidence of colorectal cancer was collected from Guangzhou Cancer Registration Annual Report (2002-2009) and China Cancer Registration Annual Report (2010-2015). The incidence and mortality data of colorectal cancer coded as C18-C21 in 10th Edition of International Classification of Diseases (ICD-10) were obtained from the above data, and the demographic data were from the Guangzhou Municipal Bureau of Statistics. Joinpoint model was used to calculate the annual change percentage (APC) and average annual change percentage (AAPC) of colorectal cancer mortality and incidence among urban residents in Guangzhou from 1972 to 2015 and from 2002 to 2015. ARIMA model was used to predict colorectal cancer mortality from 2016 to 2025. Results: There were 19 309 colorectal cancer deaths among urban residents in Guangzhou from 1972 to 2015. The crude mortality rate of colorectal cancer increased from 4.33/100 000 to 24.89/100 000 (AAPC=4.2%, P<0.001). A total of 24 033 new cases of colorectal cancer were reported in Guangzhou from 2002 to 2015. The crude incidence rate of colorectal cancer increased from 22.95/100 000 to 52.81/100 000 (AAPC=6.6%, P<0.001). The mortality rate of colorectal cancer among urban residents of Guangzhou would continuously increase from 2016 to 2025 and reach 29.53/100 000 in 2025. Conclusion: The mortality rate of colorectal cancer among urban residents of Guangzhou from 1972 to 2015 and the incidence rate of colorectal cancer from 2002 to 2015 both show an upward trend. The mortality rate will increase from 2016 to 2025.

[Epidemiology, clinical characteristics and treatment in 278 patients with coronavirus disease 2019 in Guangzhou]

Objective: To retrospective analyze the epidemiology, clinical characteristics, treatment and prognosis in patients with coronavirus disease 2019 (COVID-19). Methods: A total of 278 patients with COVID-19 admitted to Guangzhou Eighth People's Hospital from January 20 to February 10, 2020 were selected. The general demographic data, epidemiological data, clinical symptoms, laboratory examinations, lung CT imaging, treatment and prognosis were analyzed. Results: There were 130 male patients (46.8%) and 148 females (53.2%) with age (48.1±17.0) years and 88.8% patients between 20-69 years. Two hundred and thirty-six (84.9%) patients had comorbidities. Two hundred and eleven cases (75.9%) were common type. The in-hospital mortality was 0.4% (1/278). The majority (201, 72.3%) were imported cases mainly from Wuhan (89, 44.3%). The most common clinical manifestations were fever (70.9%) and dry cough (61.5%). In some patients, hemoglobin (10.4%), platelets (12.6%) and albumin (55.4%) were lower than the normal range. Other biochemical tests according to liver and function were normal, while lactic dehydrogenase (LDH) was elevated in 61 patients (21.9%), creatine kinase increased in 26 patients (9.4%). Prolonged activated partial thromboplastin time (APTT) was seen in 52 patients (18.7%), D-dimer higher than normal in 140 patients (50.4%), while 117 patients (42.1%) had elevated high-sensitivity C-reactive protein. Typical CT manifestations included single or multiple ground glass shadows especially in lung periphery in early disease which infiltrated and enlarged during progressive stage. Diffuse consolidation with multiple patchy density in severe/critical cases and even "white lung" presented in a few patients. Two hundred and forty-two patients (87.1%) received one or more antiviral agents, 242 (87.1%) combined with antibacterials, 191 (68.7%) with oxygen therapy. There were 198 patients (71.2%) treated with traditional Chinese medicine. Conclusions: COVID-19 could attack patients in all ages with majority of common type and low mortality rate. Clinical manifestations involve multiple organs or systems. Progression of the disease results in critical status which should be paid much attention.

[Development of ethylene glycol Samples in silicone tubes and their application in inter-laboratory comparison]

Objective: To development of ethylene glycol samples in silicone tubes, and the samples were applied to inter-laboratory comparison, through it to evaluate the detection capacity of occupational health testing laboratories. Methods: Three content levels of ethylene glycol samples in silicone tubes were prepared, and the homogeneity and stability of samples were investigated, the results were statistically analyzed. A robust statistical four-point distance method was used to calculate the results submitted by each participant laboratory and the test capability of the laboratory was assessed by the z-score method. Results: The statistic of the homogeneity of ethylene glycol samples in silicone tubes were less than the critical value (P>0.05) , and the samples were stable at room temperature for one month. The satisfactory rate of comparison between 204 laboratories was 88.24%. Conclusion: The homogeneity and stability of the ethylene glycol samples in the silicone tubes can meet the requirements of proficiency testing and can be used for laboratory comparison. Most of the laboratories that participated in the comparison had the ability to detect ethylene glycol.

[Determination of fluorine-ion in human urine by ion chromatography method]

Objective: To establish a method to determine fluorine ion in human urine by ion chromatography method. Methods: The samples were centrifuged, diluted and processed by C(18) solid-phase column, potassium hydroxide as mobile phase, gradient elution, separated by AS(15), and determined by anion conductivity detector. Results: The linear correlation coefficient of fluoride ion in the range of 0.02-10.00 mg/L was more than 0.999. The lowest detection limit of urinary fluoride was 0.06 mg/L (in 3 ml urine) . The recoveries of the method were 96.9%-99.5%, the inter batch precision range was 0.40%-2.89%. The intra batch precision was from 1.01 to 7.23%. Fluoride samples could be stored for 7 days at room temperature and 4 ℃, and be stored for 14 days at -20 ℃. Conclusion: Determination of fluoride in urine by ion chromatography, the method could meet the requirement in GBZ/T 210.5-2008.

[Analysis of inter-laboratory comparison results of arsenic in urine and explore the influence factors on detection]

Objective: Through inter-laboratory comparison to analysis and evaluation of the detection capacity of arsenic in the urine. Methods: Urine arsenic samples were prepared with normal human urine as matrix. The homogeneity of the samples was investigated and the results were statistically analyzed by single factor analysis of variance. 2 samples were issued to each participant laboratory. A robust statistical four-point distance method was used to calculate the results submitted by each participant laboratory and the test capability of the laboratory was assessed by the z-score method. By means of method experiments and records, the reasons of dissatisfaction and the influencing factors of the results were discussed. Results: The statistic of the homogeneity of urine arsenic samples was less than the critical value (P>0.05) , which showed that the arsenic in the sample was homogeneous. The satisfactory rate of comparison between 36 laboratories was 86.1%. The main reasons for dissatisfaction were the testing conditions and the quality control measures. The selection of sample pretreatment, acidity control and hydrogenation conditions was the main influencing factor for the determination of urinary arsenic by atomic fluorescence spectrometry. Conclusion: The level of urinary arsenic detection in the occupational health laboratories was generally better and a few laboratories need to be improved ability of detection. It was very important to control the test conditions reasonably and strengthen the quality control measures to improve the accuracy of urine arsenic detection.

Investigation of Mechanical Properties of Silicone/Phosphor Composite Used in Light Emitting Diodes Package

Mass fraction of phosphor in silicone and aging time play important roles in the optics and mechanical performance of the silicone that is used in the light emitting diode (LED) package. In this paper, the mechanical properties of silicone/phosphor composites are investigated experimentally by separate tensile and compression tests. Distribution of the phosphors is observed by scanning electron microscopy (SEM) to ensure the homogeneity of the samples. Different loading rates are applied to study the silicone material’s rate-dependent properties. The experimental results of the tensile and compression test show that the Young’s modulus increases with the mass fraction of phosphor in silicone. Longer aging time stiffens the silicone composite and weakens the ductility of the materials. A three-dimensional model used cohesive zone material (CZM) between the interface of the phosphor particles, and matrix silicone is built up to study the degradation mechanism at a micro-scale level. The simulation results indicate that the diameter of particles in silicone also impacts its interface debonding and crack growth. The theoretical results concerning the mass fraction of phosphor are in good agreement with the experiments.

[Supplementation with high-dose L-carnitine on hemodialysis tolerance in uremic patients with severe heart diseases]

Objective: To investigate the effect of intravenous supplementation with high-dose L-carnitinen on hemodialysis tolerance in uremic patients with severe heart disease (ischemic heart disease, congestive heart disease and arrhythmia). Methods: Between March 2012 and March 2017, 5 gram L-carnitine was given after the completion of each hemodialysis treatment (3-4 times a week) over a period of two weeks in 29 maintenance hemodialysis patients with severe heart diseases manifested by frequently symptomatic hypotension, chest tightness, wheezing, palpitation, chest pain and other symptoms during hemodialysis. The hemodialysis duration, heart functional classification (New York Heart Association Functional Classification, NYHA ), blood pressure and arrhythmia were analyzed before and after the treatment. Results: The duration of hemodialysis was significantly prolonged after treatment [from 2.0-3.5 (2.6±0.4)h to 3.0-4.0 (3.8±0.4) h, t=10.66, P<0.01]. Cardiac function was improved (Z=-4.74, P<0.01). The hypotension and arrhythmia during dialysis was improved. Conclusion: High-dose of intravenous L-carnitine supplementation can improve hemodialysis tolerance and the symptoms of heart failure, arrhythmia, ischemic cardiac disease in hemodialysis patients with severe heart diseases.

Ultrasonic power measurement system based on acousto-optic interaction

Ultrasonic waves are widely used, with applications including the medical, military, and chemical fields. However, there are currently no effective methods for ultrasonic power measurement. Previously, ultrasonic power measurement has been reliant on mechanical methods such as hydrophones and radiation force balances. This paper deals with ultrasonic power measurement based on an unconventional method: acousto-optic interaction. Compared with mechanical methods, the optical method has a greater ability to resist interference and also has reduced environmental requirements. Therefore, this paper begins with an experimental determination of the acoustic power in water contained in a glass tank using a set of optical devices. Because the light intensity of the diffraction image generated by acousto-optic interaction contains the required ultrasonic power information, specific software was written to extract the light intensity information from the image through a combination of filtering, binarization, contour extraction, and other image processing operations. The power value can then be obtained rapidly by processing the diffraction image using a computer. The results of this work show that the optical method offers advantages that include accuracy, speed, and a noncontact measurement method.

Nanocomposite membranes modified by graphene-based materials for anion exchange membrane fuel cells

Nanocomposite AEMs consisting of QPSF and GO or DGO showed improved alkaline solution stabilities.

Removal of Polycyclic Aromatic Hydrocarbons from Precipitation in an Urban Forest of Guangzhou, South China

Polycyclic aromatic hydrocarbon (PAH) concentrations and fluxes were measured monthly in situ from rain events in an urban forest in the megapolitan city Guangzhou, China, to investigate impacts of forest canopy and soils on PAHs. Mean Σ9-PAH concentrations were 107.5, 101.6, 106.3, 107.1 and 42.4 ng L(-1) in precipitation, throughfall, seepage water at the 30 and 60 cm soil depth, and runoff, respectively, indicating a great decrease in the form of runoff. Meanwhile, annual fluxes of total PAHs decreased from precipitation (205.9 µg m(-2) year(-1)), to throughfall (156.3 µg m(-2) year(-1)), and to seepage water (65.3 µg m(-2) year(-1) at 30-cm soil depth and 7.5 µg m(-2) year(-1) at 60-cm soil depth), but increased in runoff (34.1 µg m(-2) year(-1)). When compared to precipitation, PAH fluxes decreased by 83.4% in runoff, with 29% contributed by forest canopy and 71% by soils. Soil biodegradation explained 18.2% of PAH reduction by the surface soil layer and 34.6% by the middle soil layer.

Simultaneous construction of PCR-DGGE-based predictive models of Listeria monocytogenes and Vibrio parahaemolyticus on cooked shrimps

The aim of this study was to simultaneously construct PCR-DGGE-based predictive models of Listeria monocytogenes and Vibrio parahaemolyticus on cooked shrimps at 4 and 10°C. Calibration curves were established to correlate peak density of DGGE bands with microbial counts. Microbial counts derived from PCR-DGGE and plate methods were fitted by Baranyi model to obtain molecular and traditional predictive models. For L. monocytogenes, growing at 4 and 10°C, molecular predictive models were constructed. It showed good evaluations of correlation coefficients (R(2) > 0.92), bias factors (Bf ) and accuracy factors (Af ) (1.0 ≤ Bf ≤ Af ≤ 1.1). Moreover, no significant difference was found between molecular and traditional predictive models when analysed on lag phase (λ), maximum growth rate (μmax ) and growth data (P > 0.05). But for V. parahaemolyticus, inactivated at 4 and 10°C, molecular models show significant difference when compared with traditional models. Taken together, these results suggest that PCR-DGGE based on DNA can be used to construct growth models, but it is inappropriate for inactivation models yet. This is the first report of developing PCR-DGGE to simultaneously construct multiple molecular models.

SIGNIFICANCE AND IMPACT OF THE STUDY

It has been known for a long time that microbial predictive models based on traditional plate methods are time-consuming and labour-intensive. Denaturing gradient gel electrophoresis (DGGE) has been widely used as a semiquantitative method to describe complex microbial community. In our study, we developed DGGE to quantify bacterial counts and simultaneously established two molecular predictive models to describe the growth and survival of two bacteria (Listeria monocytogenes and Vibrio parahaemolyticus) at 4 and 10°C. We demonstrated that PCR-DGGE could be used to construct growth models. This work provides a new approach to construct molecular predictive models and thereby facilitates predictive microbiology and QMRA (Quantitative Microbial Risk Assessment).

Dilemma of applying telehealth for overseas organ transplantation: comparison on perspectives of health professionals and e-health information and communication technologists in Taiwan

INTRODUCTION

Telehealth is one of the avenues of e-health; it is a voice, image, or document delivery system via the internet and aims to assist patients to prevent disease and to promote health, diagnosis, self-care, and treatment. The purpose of using telehealth for overseas organ transplantation (OOT) was debated. This study aimed to explore the dilemma in applying telehealth for OOT patients from the perspectives of health professionals and e-health information and communication technologists (eh-ICTs) in Taiwan.

METHODS

An exploratory qualitative method was used, with a purposive sample of OT health professionals (OTHP) and eh-ICTs in Taiwan. Qualitative data were collected by face-to-face semistructured interviews, and were analyzed by content analysis.

RESULTS

Fifty subjects including 10 OT surgeons (OTS), 30 registered nurses (RNs), and 10 eh-ICTs participated in this study. Five dilemmas were identified: (1) medical law violation (80%, n = 40 of 50; 100% OTS [n = 10 of 10], 67% RNs [n = 20 of 30], 100% eh-ICTs [n = 10 of 10]); (2) integrating telecommunication and medical systems for OOT (74%, n = 37 of 50; 90% OTS [n = 9 of 10], 73% RNs [n = 22 of 30], 60% eh-ICTs [n = 6 of 10]); (3) the inconsistent caring protocols among medical parties (68%, n = 34 of 50; 80% OTS [n = 8 of 10], 70% RNs [n = 21 of 30], 50% eh-ICTs [n = 5 of 10]); (4) the uncertainty in quality of care in overseas medical institutes (62%, n = 31 of 50; 80% OTS [n = 8 of 10], 60% RNs [n = 18 of 30], 50% eh-ICTs [n = 5 of 10]); and (5) the uncertainty in cost-effectiveness (36%, n = 18 of 50; 60% OTS [n = 6 of 10], 17% RNs [n = 5 of 30], 70% eh-ICTs [n = 7 of 10]).

CONCLUSIONS

The use of telehealth for OOT is in its infancy. A systematic curriculum with advanced pilots targeted to develop telehealth for OOT will be needed for mutual communication between OTHPs and eh-ICTs in the near future.

Two novel DAX1 gene mutations in Chinese patients with X-linked adrenal hypoplasia congenita: clinical, hormonal and genetic analysis

Mutations in the DAX1 gene result in X-linked congenital adrenal hypoplasia (AHC). Affected boys usually present with primary adrenal failure in early infancy or childhood and hypogonadotropic hypogonadism (HH) at puberty. This paper describes the clinical, hormonal, radiological, and genetic characteristics of 2 Chinese patients with X-linked AHC. Primary adrenal insufficiency occurred in the 2 patients during their childhood and HH was recognized at puberty. Genomic DNA was extracted from their peripheral blood leukocytes and coding sequence abnormalities of the DAX1 gene were assessed by PCR and direct sequencing analysis. Genetic analysis of the DAX1 gene revealed 2 novel mutations c.572-575 dupGGGC, p.Thr193Gly,fs,205X and c.773- 774 dupCC, p.Ser259Pro,fs,264X in exon 1, causing frameshifts and yeilding premature stop codons at 205 and 264, respectively. This study identifies 2 novel mutations in the DAX1 gene which can further expand the mutation database and benefit patients in the diagnosis and treatment of AHC.

Brazilein inhibits survivin protein and mRNA expression and induces apoptosis in hepatocellular carcinoma HepG2 cells

Hepatocellular carcinomas represent the third leading cause of cancer-related deaths worldwide. Survivin, a structurally unique member of the inhibitor of apoptosis protein (IAP) family, is overexpressed in a wide range of malignancies, including hepatocellular carcinoma. Due to its involvement in cancer progression and treatment resistance, survivin is currently undergoing extensive investigation as a novel intervention target to induce apoptosis in cancer cells by phytochemicals or synthetic agents. Brazilein, a compound obtained in a large amount from the dried heartwood of Caesalpinia sappan Linn., which has long been used in traditional medicine in China, has some pharmacological activities. Human hepatocellular carcinoma HepG2 cells were treated with brazilein and analyzed for survivin protein and mRNA levels by Western blotting and real-time RT-PCR, respectively. Brazilein treatment of cells for 48 h at 5 and 10 microg/ml doses resulted in significantly decrease in survivin protein expression. We also observed that brazilein caused a strong decrease in survivin mRNA expression. In other studies, down-regulation of survivin by brazilein was associated with a strong and prominent caspases-9 and -3 activation as well as PARP cleavage. It was also shown that brazilein induced a strong apoptotic cell death, as shown by DNA ladder assay, and growth inhibition of HepG2 cells. Further studies are needed to investigate in vivo effect of brazilein on survivin expression and associated biological effects in hepatocellular carcinoma that could provide useful information for brazilein efficacy in the prevention/intervention of human hepatocellular carcinoma.

[Studies on chemical structure of polysaccharide from fruit body of Coriolus versicolor]

AIM

To study the structure of polysaccharides from Coriolus versicolor.

METHODS

By chromatography a homogeneous polysaccharide B-1-3 was obtained. The structure of B-1-3 was elucidated using the method of total acid hydrolysis, methylation, and 1D and 2D NMR.

RESULTS

B-1-3 was found to be mainly composed of Glc by total acid hydrolysis. Its molecular weight was estimated to be 3.16 x 10(5) by HPLC method. Methylation analysis and 1H and 13CNMR indicated the main chain of B-1-3 consisted of beta-D-1,4-Glc and beta-D-1,3-Glc, and branch chains were situated, beta-D-1,3,6-Glc and beta-D-1,4,6-Glc. 1H and 13CNMR also showed that beta-D-Glc-1-->3-beta-D-Glc-beta-D-Glc-1-->4-beta-D-Glc and beta-D-Glc-1-->4-beta-D-Glc-beta-D-Glc-1-->4-beta-D-Glc fragments existed in B-1-3.

CONCLUSION

B-1-3 is a glucan which main chain was composed of beta-D-1,4-Glc and beta-D-1,3-Glc beta-D-1,6-Glc.

[New triterpenoid saponins from Anemone begoniifolia]

AIM

To study the triterpenoid saponins in the whole plants of Anemone begoniifolia Lévl. et Vant.

METHODS

Methanol extraction, normal and reversed phase silica gel column chromatography and various spectral analysis were used to isolate and determine the structures of the triterpenoid saponins.

RESULTS

Four triterpenoid saponins were idenetified as: 3-O-beta-D-glucopyranosyl(1-->2)-alpha-L-arabinopyranosyl oleanolic acid 28-O-alpha-L-rhamnopyranosyl (1-->4)-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranoside (1), 3-O-beta-D-glucopyranosyl (1-->3)-alpha-L-arabinopyranosyl oleanolic acid 28-O-alpha-L-rhamnopyranosyl (1-->4)-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranoside (2), 23-O-methyl malonyl hederagenin 28-O-alpha-L-rhamnopyranosyl (1-->4)-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranoside (3) and 3-O-methyl malonyl hederagenin 28-O-alpha-L-rhamnopyranosyl (1-->4)-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranoside (4).

CONCLUSION

Compunds 2, 3 and 4 are new compounds and named as begoniifolides A, B and C, respectively.

Influence of several grating sensor parameters on the modulation depth of moiré signals under incoherent illumination

Theoretical expressions for the modulation depth of moiré signals under incoherent illumination are derived. Consequently, the modulation depth of a moiré signal is related to the following factors: the geometric shape and the size of the light source; the diffraction effect of the grating, which relates to the number of lines in the grating; the line and the space ratio; the grating pair gap; the geometric shape and the size of the receiving window; etc. In addition, the influence of the grating pair on the period and the inclination of moiré fringes under noncollimated illumination are discussed, and the changes in the moiré signal modulation depth under noncollimated illumination with that under collimated illumination are made. Finally, some experimental results are given to verify the theoretical expressions. This research is useful for the actual design of grating sensors.

Environmental and dietary risk factors for nasopharyngeal carcinoma: a case-control study in Zangwu County, Guangxi, China

A case-control study was conducted on 88 incident cases of histologically confirmed undifferentiated nasopharyngeal carcinoma (NPC) in Zangwu County, China, and 176 age- sex- and neighbourhood-matched controls. The design of this study was defined after an anthropological survey on living habits in regions of high NPC incidence and the evidence of carcinogenic substances in some commonly consumed preserved foods. Subjects were interviewed regarding living conditions and diet in the year preceding the diagnosis of NPC and, with the help of their families, during childhood and weaning. After adjustment for a living conditions score to eliminate a confounding effect, an increased risk associated with consumption of salted fish during weaning and childhood was confirmed, especially for salted fish in rice porridge. The consumption of leafy vegetables was associated with a reduced risk for NPC, and consumption of melon seeds between 2 and 10 years of age with an increased risk. After multivariate analysis and adjustment according to the living conditions score, the consumption of salted fish in rice porridge before age 2 (OR = 3.8, P = 0.005), exposure to domestic woodfire (OR = 5.4, P = 0.01) and consumption of herbal tea (OR = 4.2, P = 0.02) were found to be independently related to the risk of NPC. The excess risk associated with the use of domestic wood fire increased if there were no windows in the house and with poor ventilation and cooking outside the house in a shack. As well as confirming the importance of the consumption of salted fish in childhood, this study has been the first to provide unequivocal evidence for two other factors implicated in increasing the risk of NPC in China, the adult consumption of traditional medicines (herbal tea) and exposure to domestic wood fumes.

Diterpenoid Alkaloids from Delphinium caeruleum

A new minor diterpenoid alkaloid, caeruline, was isolated from DELPHINIUM CAERULEUM Jacq. ex Camb. Its structure was elucidated as 1 on the basis of spectral evidence. Along with this new compound, three known diterpenoid alkaloids were also isolated from this plant and identified as tatsiensine, delcosine, and lycoctonine which had not been found in this herb previously.

Role of renal nerves in compensatory adaptation to chronic reductions in sodium intake

The aim of this study was to investigate the importance of the renal nerves in adaptation to chronic reductions in sodium intake. Conscious dogs with unilateral (n = 7) or bilateral (n = 4) renal denervation were studied. In dogs studied before and after bilateral denervation, there were no differences in urine volume (UO), Na excretion (UNaV), or fractional reabsorption of Li (FR Li, an index of proximal tubular Na reabsorption) between innervated and denervated kidneys on either normal (80 meq/day) or low Na intake (5 meq/day, 15 days). Plasma renin activity (PRA) was attenuated following denervation on both normal (0.39 +/- 0.06 vs. 0.18 +/- 0.01 ng angiotensin I X ml-1 X h-1) and low Na intake (1.00 +/- 0.06 vs. 0.59 +/- 0.01). In unilaterally denervated dogs the left kidney was denervated and the bladder was split, allowing continuous urine collection from separate innervated and denervated kidneys in the same dog. There was no difference in UO between innervated and denervated kidneys on normal (80 meq/day) or low (7 meq/day, 9 days) Na intake. UNaV averaged 33.6 +/- 1.3 and 37.6 +/- 2.1 meq/day in innervated and denervated kidneys, respectively, on normal Na intake and 3.5 +/- 0.5 and 4.0 +/- 0.4 meq/day in innervated and denervated kidneys on low Na intake. FR Li was not different in denervated compared with innervated kidneys during normal or low sodium intake. Norepinephrine content was reduced by 99 +/- 1% in denervated kidneys.(ABSTRACT TRUNCATED AT 250 WORDS)

The pathogenic role of the kidney

The discussions of this article suggest that the pressure natriuresis mechanism of the kidneys is the most important of all long-term regulators of arterial pressure. This is especially so because of the infinite-gain feature of this mechanism, a feature that is explained here. However, experiments have shown that it is not the accumulation of sodium per se in the body that causes hypertension. Instead, it is the increase in extracellular fluid volume that usually accompanies sodium accumulation that increases the arterial pressure. If the increase in fluid volume is prevented, hypertension will not occur despite marked sodium retention. Long-term autoregulation in hypertension plays a very important role for two major reasons: (a) it greatly increases the total peripheral resistance when the cardiac output increases only a small amount, and (b) when it promotes arteriolar constriction, capillary pressure is reduced, which in turns allows a very large proportion of the extracellular fluid to remain in the blood rather than to leak into the interstitium. Marked loss of renal mass usually does not cause hypertension because, as long as there is a proper balance between glomerular filtration capability and tubular reabsorption capability, as little as 10% of the normal kidney mass theoretically can excrete the normal daily load of salt without a significant rise in arterial pressure. However, whenever the ratio of glomerular filtration capability to tubular reabsorption capability falls below normal, salt and water are retained until enough hypertension develops to overcome the deficit in glomerular filtration.

Experimental aldosterone hypertension in the dog

Sequential changes in arterial pressure, renal function, body fluid, and electrolyte balance, and several hemodynamic variables were examined during chronic intravenous infusion of aldosterone (14 micrograms/kg/day) in eight conscious dogs maintained on 250 mEq/day sodium and 140 mEq/day potassium intake. Arterial pressure gradually increased and stabilized at 132% +/- 3% (p less than 0.05) of the control value on the 16th day of aldosterone infusion, and cardiac output remained within the normal range. Coinciding with the rise in arterial pressure on the first 2 days of infusion was a marked retention of water and sodium and a rise in extracellular fluid volume and blood volume. Blood volume increased from a baseline value of 64.0 +/- 0.3 ml/kg to 70.7 +/- 1.9 ml/kg (p less than 0.05) on Day 4 and extracellular fluid volume increased from 318 +/- 5 ml/kg to 352 +/- 11 ml/kg (p less than 0.05) on Day 3 of infusion. Both blood volume and extracellular fluid volume remained elevated during infusion. Mean circulatory filling pressure increased from the baseline volume of 9.7 +/- 0.4 mm Hg to an average of 11.7 +/- 0.3 mm Hg (p less than 0.05) during the experimental period. The elevation of mean circulatory filling pressure suggested that this increase may be an essential component in the onset and maintenance of hypertension.

Control of extracellular sodium concentration by antidiuretic hormone-thirst feedback mechanism

The effectiveness of the antidiuretic hormone (ADH)-thirst feedback mechanism to control extracellular sodium concentration was studied in dogs. The design consisted of increasing daily sodium intake from 10 to 200 meq in a group of dogs, first in the normal condition and second with a continuous 24 h/day infusion of an amount of ADH sufficient to maintain urine osmolarity at a maximal level and with fixed water intake. We were therefore able to compare the effectiveness of sodium concentration control in the same dogs with and without feedback control of the ADH-thirst mechanism, the difference in effectiveness being a quantitative measure of the control capability of the system. In the normal condition the increase in sodium intake resulted in a steady-state 2.3% elevation in sodium concentration. With the feedback control of ADH secretion and water intake blocked, the same sodium forcing produced an 11.9% increase in extracellular sodium concentration. The minimum feedback gain for the system calculated from the data is -4.2. We conclude that control of sodium concentration in the intact state is accomplished mainly by the ADH-thirst feedback mechanism.

The natriuretic and hypotensive effects of potassium

The chronic effects of potassium loading on sodium balance and related variables were studied in two groups of dogs. The first group was intact except for the presence of indwelling arterial and venous cannulas. On the 1st day, increasing daily potassium intake from a normal level (30 mEq/day) to 200 mEq/day produced a 0.47-mEq increase in plasma potassium with a 56% increase (P greater than 0.01) in sodium excretion in spite of a 58% increase in plasma aldosterone concentration. After 6 days of potassium loading the cumulative negative sodium balance averaged 44 mEq while 22Na space decreased 6.7% (P less than 0.025). In this group arterial pressure did not change measurably. The same experimental protocol was repeated in a second group of dogs that were chronically adrenalectomized and maintained on fixed levels of aldosterone (50 mug/day) and hydrocortisone (1 mg/day). With aldosterone levels held constant the same increase in potassium intake produced a 1st day increase in potassium concentration of 1.20 mEq/liter and 217% (P less than 0.001) increase in sodium excretion. After 5 days of high potassium intake, the cumulative negative sodium balance totaled 84 mEq. Sodium space decreased 7.5% (P less than .005) during the course of the 5-day high potassium intake period. Potassium loading caused a fall in mean arterial pressure in this group; pressure fell from the control level of 110 +/- mm Hg to 87 +/- 4 mm Hg (P less than .001) after 3 days of high intake. By the 5th day of the experiment, pressure stabilized at 96 +/- 3 mm Hg, 13% less than (P less than 0.01) the control level. The results suggest that changes in plasma potassium concentration within physiological limits may have long term effects on sodium balance.