An improved method for rapid identification of hook effect samples in HBsAg quantitative assay.

Quantitative hepatitis B surface antigen assay is widely used for diagnosis of hepatitis B virus infection; however, specimens with high levels of the antigen can cause false-negative results (Hook effect), which needs to be resolved. The hook effect samples and non-hook effect samples were detected on the LiCA® 500 instrument using three methods, viz., 1, 2, and 3. Method 1, the currently used procedure, was performed in two steps with a total reaction time of 25 min in a final volume of 250 µL: first incubation was with two reagents for 15 min and then with one other reagent for 10 min. In Method 2, all three reagents were added in one step with a final volume of 250 µL, and the total reaction time was still 25 min. In Method 3, the improved method, all three reagents were added in one step while the final volume was only 130 µL and the total reaction time was only 1 min. Signal values of the non-hook effect samples obtained using Method 2 were significantly lower than those with Method 1, showing competitive inhibition. The hook effect samples tested with Method 2 approximated those obtained using Method 1. Method 3 took 1 min and differentiated hook effect samples successfully, similar to the results with Method 2 which took 25 min. Changing the timing of one reagent addition and incubation time in Method 3 provided a rapid and effective method for the identification of hook effect. The results were more clearly distinguishable due to the phenomenon of competitive inhibition. Method 3 can be considered an improvement on the chemiluminescence platform.

A Rapid Method for Extracting High-Quality DNA from Soils.

Metagenomics offers the possibility to study the microbial community of soils at large scale, allowing the characterization also of unculturable microorganisms. Availability of high-quality DNA is a prerequisite of this approach. However, since soils have highly heterogeneous physicochemical properties, several parameters need to be considered for the development of the best molecular practices. A method for isolation of high-molecular-weight and good-quality metagenomic DNA from different soil samples is described here. The protocol combines physical and chemical strategies to ensure efficient cell lysis and precipitation of humic impurities-free DNA suitable for downstream processing for metagenomics study.

An improved method to generate megakaryocytes from human induced pluripotent stem cells / 中国输血杂志

【Objective】 To optimize the existing spin-EB method and promote human induced pluripotent stem cells (hiPSCs) differentiate into megakaryocytes (MKs). 【Methods】 In this study, the initial inoculation amount of hiPSCs was increased from 3 500 cells/well to 8 000 cells/well, and the size of EB was increased. By observing the generation time of EB- hematopoietic cells during differentiation, and detecting the proliferation of CD34+ hematopoietic progenitor cells and CD41+ MKs in different stages, it was studied whether the optimized scheme could promote the differentiation of hiPSCs into hematopoietic progenitor cells(HPCs) and MKs. 【Results】 By increasing the initial inoculation amount of hiPSCs and the size of EB, the differentiation of hiPSCs into HPCs and MKs and the cell production efficiency can be promoted. 【Conclusion】 Our research describes an optimized and repeatable differentiation method, which can produce hematopoietic progenitor cells and mature MKs from hiPSCs in a relatively short time with higher yield. It is of great clinical significance and broad scientific research prospect to continuously optimize the culture scheme of hiPSCs differentiation to produce MKs and platelets in vitro, and to promote large-scale platelet generation in vitro in transfusion medicine.

Improved method for production of chitin and chitosan from shrimp shells.

In this study, pretreatment procedures have been investigated preceding the standard production of chitin and chitosan. These steps can be used in industrial processes to preserve raw shrimp shells as long as the amount of material is not enough for one production batch. After these treatments, shrimp shells are clean and are facile for further demineralization, deproteinization and deacetylation processes. The prepared chitin and chitosan show a high purity with very low ash (less than 0.3%) and protein residues (less than 0.5%), along with their high molecular weight and high crystallinity. This modified approach has potential for application in large-scale production due to its ease of operation and reduction of environmental concerns.

An Improved Method for the Identification of Soybean Resistance to Phytophthora sojae Applied to Germplasm Resources from the Huanghuaihai and Dongbei Regions of China.

Phytophthora root and stem rot (PRR) caused by Phytophthora sojae is a destructive disease afflicting soybean. The use of resistant cultivars is the most effective method to combat PRR. PRR resistance was assessed in 223 soybean cultivars from Huanghuaihai and Dongbei, major soybean-producing regions in east central and northeastern China. To evaluate levels of soybean resistance to P. sojae, we used eight representative P. sojae isolates and a modified etiolated hypocotyl-slit inoculation method. The cultivars Wandou21020, Xu9302-A, Kedou10, and Lidi055 showed resistance to all eight isolates; 14 cultivars showed intermediate resistance to all eight P. sojae isolates, and 53 cultivars were resistant to seven isolates. Thirty-three cultivars (15%) were susceptible only to the highly virulent PsJS2 isolate, which is consistent with the reactions of the Chapman differential line that carries Rps3a. The diverse reaction patterns seen in germplasm from different regions (provinces/cities) in this study reflect the variety of PRR-resistant soybean sources in China. Our research indicates that sources of P. sojae resistance are present in the major soybean production areas of China. This study provides useful information for soybean breeding programs.

An improved method of culturing somatotropic cells from rat adenohypophysis.

This study aimed to propose a simple and practical method for culturing primary rat somatotropic cells in vitro free of pericytes contamination. Rat adenohypophyses were randomly divided into two groups. An improved method was used in group A (digesting adenohypophysis with 0.25% trypsin-EDTA, followed by removing pericytes by double filtration and using serum-free medium for culturing somatotropic cells). The traditional method was used in group B (digesting adenohypophysis with 0.35% collagenase, using serum medium for culturing somatotropic cells, and removing pericytes by changing the culture dish). The numbers and viability of somatotropic cells were higher in group A than in group B after 6 days. GH secretion of somatotropic cells was also higher in group A than in group B. Besides, the pericytes grew rapidly only in group B after 3 days. α-SMA, type I collagen, and type III collagen had weaker expression in group A. Also, the viability of pericytes decreased in group A. The improved method could solve the problem of pericytes contamination, and the culture of primary rat somatotropic cells in vitro was successful. This method can be used for other primary cultures with pericytes contamination.

Application and Extension of Vertical Intensity Lower-Mode in Methods for Target Depth-Resolution with a Single-Vector Sensor.

In this paper, based on the reactive component of the vertical intensity, the method for target depth resolution has been improved. In the previous existing research results, using the reactive component of vertical intensity, the research objects for target depth resolution in shallow water, can only be the targets whose frequencies can only excite the first two normal modes, and the depth of targets whose frequencies excite more than two normal modes cannot be correctly identified. The basic idea of the improved method is to classify targets on the foundation of the lower-mode correlation quantity of the vertical intensity. Based on the improved method, we can realize depth resolution of the targets whose frequency can excite the first three normal modes so as to effectively expand the working band useful for target depth resolution. Finally, we can realize the three-dimensional target depth resolution so as to distinguish the aerial, surface and underwater targets. The feasibility of the algorithm is verified by simulation and experimental data processing.

Improved method for qualitative screening of lipolytic bacterial strains.

Esterases and lipases are lipolytic enzymes that catalyse the hydrolysis of triacylglycerols, Determination of lipolysis on agar plates is a simple approach to determine lipase or esterase action, but visual evaluation of lipolysis is frequently difficult in practice. Therefore, the aim of this work was to improve the efficiency of lipolysis visualization in tributyrin agar (mTBA) by adding calcium and/or magnesium ions in the screening of lipolytic microbial strains. Lipolytic activity was evaluated in mTBA using the well diffusion technique, where a clear zone around the inoculated wells indicated lipid hydrolysis. Results suggest that the addition of 2.5 mM calcium and 5.0 mM magnesium was the best combination of ion addition to TBA. Lipolytic activity increased the clearing zone up to 38% more than without the addition of ions and the clear zone was clearly observed. The mTBA plate was used with culture collection microbial strains, as well as with a collection of soil microorganisms, to identify lipase producers. The addition of calcium and magnesium ions can provide an easier screening procedure for selection of lipolytic bacterial strains. •A modified tributyrin agar for screening of lipolytic bacteria was prepared by adding calcium and magnesium ions.•The modified TBA agar was tested with control bacterial strains, and, based on the results, 2.5 mM Ca and 5.0 mM Mg ions were added in the mTBA.•mTBA was validated with environmental bacterial strains for screening of lipolytic activity.

Gastrointestinal polyp detection in endoscopic images using an improved feature extraction method.

Gastrointestinal polyps are treated as the precursors of cancer development. So, possibility of cancers can be reduced at a great extent by early detection and removal of polyps. The most used diagnostic modality for gastrointestinal polyps is video endoscopy. But, as an operator dependant procedure, several human factors can lead to miss detection of polyps. In this peper, an improved computer aided polyp detection method has been proposed. Proposed improved method can reduce polyp miss detection rate and assists doctors in finding the most important regions to pay attention. Color wavelet features and convolutional neural network features are extracted from endoscopic images, which are used for training a support vector machine. Then a target endoscopic image will be given to the classifier as input in order to find whether it contains any polyp or not. If polyp is found, it will be marked automatically. Experiment shows that, color wavelet features and convolutional neural network features together construct a highly representative of endoscopic polyp images. Evaluations on standard public databases show that, proposed system outperforms state-of-the-art methods, gaining accuracy of 98.34%, sensitivity of 98.67% and specificity of 98.23%. In this paper, the strength of color wavelet features and power of convolutional neural network features are combined. Fusion of these two methodology and use of support vector machine results in an improved method for gastrointestinal polyp detection. An analysis of ROC reveals that, proposed method can be used for polyp detection purposes with greater accuracy than state-of-the-art methods.

Gastrointestinal polyp detection in endoscopic images using an improved feature extraction method

Gastrointestinal polyps are treated as the precursors of cancer development. So, possibility of cancers can be reduced at a great extent by early detection and removal of polyps. The most used diagnostic modality for gastrointestinal polyps is video endoscopy. But, as an operator dependant procedure, several human factors can lead to miss detection of polyps. In this peper, an improved computer aided polyp detection method has been proposed. Proposed improved method can reduce polyp miss detection rate and assists doctors in finding the most important regions to pay attention. Color wavelet features and convolutional neural network features are extracted from endoscopic images, which are used for training a support vector machine. Then a target endoscopic image will be given to the classifier as input in order to find whether it contains any polyp or not. If polyp is found, it will be marked automatically. Experiment shows that, color wavelet features and convolutional neural network features together construct a highly representative of endoscopic polyp images. Evaluations on standard public databases show that, proposed system outperforms state-of-the-art methods, gaining accuracy of 98.34%, sensitivity of 98.67% and specificity of 98.23%. In this paper, the strength of color wavelet features and power of convolutional neural network features are combined. Fusion of these two methodology and use of support vector machine results in an improved method for gastrointestinal polyp detection. An analysis of ROC reveals that, proposed method can be used for polyp detection purposes with greater accuracy than state-of-the-art methods.

An improved method suitable for isolation of high-quality metagenomic DNA from diverse soils.

Standardization of metagenomic DNA extraction protocol is a pre-requisite for a successful metagenomic study aiming to screen and exploit the variety of microorganisms inhabiting a particular soil environment. Six methods reported earlier were used for isolation of metagenomic DNA in the present study. These methods suffered with regard to either poor yield or quality of DNA. Therefore, we developed an improved method for isolation of high-molecular weight and good quality metagenomic DNA from different soil samples. Our protocol combines the enzymatic (lysozyme and proteinase K) and chemical (CTAB and CaCl2) strategies to ensure efficient cell lysis and use of PEG and isopropanol for precipitation of humic impurities-free DNA. Our improved method gave high yield of good quality metagenomic DNA from diverse soils collected from garden, domestic waste dumping site, cellulose waste dumping site, sewage site, and tannery waste site. The good quality of the metagenomic DNA was evident by spectrophotometry data, PCR amplification of 16S rRNA gene and restriction digestion.

Application of three-line positioning method in blood collection by cardiac puncture from rats / 局解手术学杂志

Objective To introduce an improved method for collecting the blood of rat by cardiac puncture .Methods The study se-lected 90 Wistar rats,half male and half female ,and then the rats were anesthetized by intraperitoneally injecting 10％chloral hydrate solution according to 0.3 mL/kg body weight.Then using three-line positioning method to determine the puncture site ,the blood collection needle and blood collection tube were used to collecting the blood ,Finally,the blood volume of each rat was recorded .Results The success rate was cal-culated according to the single blood collection of 5 mL or more,and our 90 rats were collected 90 times,the success rate was about 82.2％. After centrifugation,the total serum was about 260 mL,the average serum separation of each rat was about 2.8 mL.Conclusion The im-proved positioning method of heart blood collection is intuitive and easy to learn ,and the total volume and quality of blood is high ,besides ,the new method has a small surgical trauma and a high efficiency ,which is worth to extend .

Improved method for measurement of multi-walled carbon nanotubes in rat lung.

BACKGROUND: Previously, we have developed and reported the method of measuring multi-walled carbon nanotube (MWCNT) in the lung from rats exposed to MWCNT intratracheally. The present research was performed to improve the analytical method of MWCNT to measure multiple samples in a short period of time. For the xanalysis of MWCNTs from tissues, the existence of carbon black may interfere. Therefore, it was examined whether or not carbon black interfere the determination of MWCNT in the standard solutions. Then, MWCNTs were administered to rats and the MWCNTs were determined in the rats by the new method and the recovery rates and time for determination were calculated. The standard solutions for MWCNTs and carbon black were prepared, and the concentrations in the solutions were determined by HPLC with checking their linearity between the concentrations and signal intensities. The reproducibility of the determination was also checked. METHODS: The concentrations of MWCMTs in the standard solutions were determined by HPLC with a fluorescent detector. Those of carbon black were also determined using the same method. The MWCNTs were administered to rats intratracheally. The MWCNTs in the lung were determined in a newly modified method including digestion of lung tissues by strong alkali solution and marking MWCNTs by benzo[ghi]perylene. The time for the determinations was recorded and the recovery rate of MWVNTs was calculated. RESULTS: MWCNT showed linearity in a range of 0.2 to 1.0 µg/mL. In contrast, carbon black demonstrated a very low slope, showing flat pattern. Regarding the reproducibility of the analysis, the coefficient of variation was lower than 10 %. The analysis of 20 samples were completed in 1.5 h. The recovery rates of MWCNT from the lung of rats receiving intratracheal MWCNT administration were 101 to 102 %. CONCLUSIONS: The improved method for measuring MWCNT allows an efficient MWCNT quantitation in a short period of time. Also, a small amount of MWCNTs can be measured without influence of carbon black.

An improved method for measuring metaldehyde in surface water using liquid chromatography tandem mass spectrometry.

The molluscicide metaldehyde (2,4,6,8-tetramethyl-1,3,5,7-tetraoxocanemetacetaldehyde) is an emerging pollutant. It is frequently detected in surface waters, often above the European Community Drinking Water Directive limit of 0.1 µg/L for a single pesticide. Gas chromatography mass spectrometry (GC-MS) can be used to determine metaldehyde in environmental waters, but this method requires time consuming extraction techniques prior to instrumental analysis. Use of liquid chromatography-tandem mass spectrometry (LC-MS/MS) can overcome this problem. We describe a novel LC-MS/MS method, using a methylamine mobile phase additive, coupled with on-line sample enrichment that allows for the rapid and sensitive measurement of metaldehyde in surface water. Only the methylamine adduct of metaldehyde was formed with other unwanted alkali metal adducts and dimers being suppressed. As considerably less collision energy is required to fragment the methylamine adduct, a five-fold improvement in method sensitivity, compared to a previous method using an ammonium acetate buffer mobile phase was achieved. This new approach offers: •A validated method that meets regulatory requirements for the determination of metaldehyde in surface water.•Improved reliability of quantification over existing LC-MS/MS methods by using stable precursor ions for multiple reaction monitoring.•Low limits of quantification for tap water (4 ng/L) and river water (20 ng/L) using only 800 µL of sample; recoveries > 97%.

Improvement of Content Determination for Polygala XanthoneⅢin Polygalae Radix / 中国药房

OBJECTIVE:To improve the content determination for polygala xanthone Ⅲ in Polygalae Radix contained in Chi-nese Pharmacopoeia (2010 edition). METHODS:HPLC was performed on the column of Hypersil BDS C18 with mobile phase of acetonitrile-0.05% phosphoric acid(gradient elution)at a flow rate of 1.0 ml/min;detection wavelength was 320 nm,column tem-perature was 25℃,and the injection volume was 10μl. RESULTS:The linear range of polygala xanthoneⅢwas 0.029-0.928 μg/ml (r=0.999 1);RSDs of precision,stability and reproducibility tests were lower than 2.0%;recovery was 94.66%-100.90%(RSD=2.46%,n=6). CONCLUSIONS:The method is simple,stable and reproducible. Although the determination time is prolonged,it has improved the accuracy and it is more suitable for the content determination of polygala xanthoneⅢin Polygalae Radix.

Study on current status and problems of continuing medical education (CME) in Beijing Shijitan Hospital / 中华医学教育探索杂志

To understand the continuing medical education status of Beijing Shijitan Hospital,so as to continue to reform and improve the teaching management of continuing medical education.,literature and information retrieval methods were used and relevant personnel was interviewed about the content,form,time and suggestions of continuing medical education.The results indicate the presence of training content is too wide,training methods are too simple,and there is lack of medical humanities quality training and other issues in continuing medical education.Variety of training methods should be increased,the quality of medical humanities education and training should be enhanced,featured training should be developed to make the continuing medical education more scientific,standardized and highly efficient.

The clinical utility of improved percutaneous lung biopsy under CT guidance / 中国医师进修杂志

Objective To discuss the clinical value of improved percutaneous lung biopsy under CT guidance.Methods Reviewed the clinical data of 80 cases of improved percutaneous lung biopsy under CT guidance,which were confirmed by surgery or pathology.When took the operation,18 G semi-automatic cutting biopsy needle (made in American Cook's company) was used to improve the ways of positioning scan,two-step method of insert the needle,and the cutting technique of coaxial in each direction.Results All of the 80 patients were successfully completed pathological biopsy,successful rate was 100.0％ (80/80),and diagnosis rate was 98.8％ (79/80),incidence of complication was 10.0 ％ (8/80),all of these patients were recovered after treatment 2-5 d.Conclusion The method of improved percutaneous lung biopsy under CT guidance is safe,effective,simple and practical,which has high successful rate and low complication rate,the generalizability is certain.

An Improved Method of Internal Hemorrhoid Ligation Treatment / 中国医师杂志

Objective To compare the clinical efficacy and safety between the improved ligation method and the traditional ligation method in the treatment of internal hemorrhoid. Methods Double blind and randomized study were made in 86 patients with internal hemorrhoid. The traditional method was performed by ligation of internal hemorrhoidal body, and the improved method was to ligate rectal mucous membrane above internal hemorrhoidal radicles. Results The improved method has better effect than the traditional method. The clinical symptoms of internal hemorrhoid such as bleeding,pain,constipation,edema,itching and erosion in the patients treated by the improved method were significantly improved compared with the patients treated by the traditional method(P