Kinetic cluster and α-divergence-based dynamic myocardial factorial analysis of positron-emission computed tomography images / 南方医科大学学报

<p><b>OBJECTIVE</b>We purpose a novel factor analysis method based on kinetic cluster and α-divergence measure for extracting the blood input function and the time-activity curve of the regional tissue from dynamic myocardial positron emission computed tomography(PET) images.</p><p><b>METHODS</b>Dynamic PET images were decomposed into initial factors and factor images by minimizing the α-divergence between the factor model and actual image data. The kinetic clustering as a priori constraint was then incorporated into the model to solve the nonuniqueness problem, and the tissue time-activity curves and the tissue space distributions with physiological significance were generated.</p><p><b>RESULTS</b>The model was applied to the 82RbPET myocardial perfusion simulation data and compared with the traditional model-based least squares measure and the minimal spatial overlap constraint. The experimental results showed that the proposed model performed better than the traditional model in terms of both accuracy and sensitivity.</p><p><b>CONCLUSION</b>This method can select the optimal measure by α value, and incorporate the prior information of the kinetic clustering of PET image pixels to obtain the accurate time-activity curves of the tissue, which has shown good performance in visual evaluation and quantitative evaluation.</p>

Regulatory T Cell Activity in Immunosuppresive Mice Model of Pseudomonas Aeruginosa Pneumonia / 华中科技大学学报（医学）（英德文版）

Pseudomonas aeruginosa (PA) pneumonia is a refractory,even lethal complication in immunosuppressive individuals and immune disturbances may promote the pathological process.We aimed to investigate the regulatory T (Treg) cell activity in an immunosuppressive mice model of PA pneumonia by estimating levels of main transcription factor and the main effector of Treg cells,i.e.,Forkhead box protein 3 (FOXP3) and interleukine-10 (IL-10).Seventy-two BALB/c mice were divided into four groups randomly:control (A),PA pneumonia (B),immunosuppression (C) and immunosuppression with PA pneumonia (D).Mice were sacrificed at 4,8 and 24 h after establishing experimental models.The pathological changes of lung tissue were graded,and the FOXP3 mRNA and serum IL-10 levels were detected.Histological analysis of lung tissues showed there were no significantly pathological changes in groups A and C,but significantly pathological changes were found in groups B and D,especially in group D at 8 h (P＜0.05).The expression levels of FOXP3 mRNA in groups A and C showed no significant changes at the three time points,which were significantly lower than those in groups B and D (P＜0.05).FOXP3 mRNA levels were lowest at 4 h,and there was significant difference between groups B and D (P＜0.05).The serum levels of IL-10 in groups A and C were almost normal at the three time points,but decreased significantly in groups B and D (P＜0.05).The serum levels ofIL-10 decreased to the lowest at 8 h,especially in group D (P＜0.05).The results indicate that PA pneumonia in immunosuppressive individuals worsens rapidly,which may be associated with Treg cells function disturbance.And Treg cells may be promising as adjuvant therapeutics for PA pneumonia in immunosuppressive individuals.

Identification of A Novel HLA Allele DRB1 * 16:36 by Sequencing-Based Typing / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To identify a novel HLA allele DRB1 * 16:36 from a Uygur woman.</p><p><b>METHODS</b>PCR-SBT technology was applied to the extracted DNA for genotyping, and a possible new gene was sequenced by using sequence specific primers and single stranded SBT. This novel allele was compared with known most homologous gene sequences and their difference was analyzed.</p><p><b>RESULTS</b>This novel allele was different from HLA alle DRB1 * 16:23, and had highest similarity in 2 nucleotides at position 227 A→T and 236 T→C in exon 2, resulting in 3 amino acid changes from Tyr to Phe at codon 47 and Val to Ala at codon 50. The sequence of this novel allele had been submitted to GenBank.</p><p><b>CONCLUSION</b>This HLA allele DRB1 * 16:23 has been confirmed to be a novel allele, and has been officially named DRB1 * 16:36 by the World Health Organization (WHO) Nomenclature Committee in May 2015.</p>

Reconstruction of dynamic positron emission tomographic images by exploiting low rank and sparse penalty / 南方医科大学学报

<p><b>OBJECTIVE</b>To propose a new method for dynamic positron emission tomographic (PET) image reconstruction using low rank and sparse penalty (L&S).</p><p><b>METHODS</b>The L&S reconstruction model was established and the split Bregman method was used to solve the optimal cost function. The one-tissue compartment model was used to simulate a set of PET 82Rb myocardial perfusion image. The L&S reconstruction method was compared with maximum likelihood expectation maximization (MLEM) method, low-rank penalty method and sparse penalty method.</p><p><b>RESULTS</b>The L&S reconstruction method had the smallest MSE and well maintained the feature information. The polar map created by L&S method was the most similar with the reference actual polar map.</p><p><b>CONCLUSION</b>L&S reconstruction method is better than the other three methods in both visual and quantitative analysis of the PET images.</p>

Incorporation of TV regularization in deconvolution for partial volume correction in PET imaging / 南方医科大学学报

We propose a method using total variation (TV) regularization in deconvolution for partial volume correction in PET imaging. In the degraded image model, we used TV regularization procedure in Van Cittert (VC) and Richardson-Lucy (RL) deconvolution algorithms. These methods were tested in simulated NCAT images and images of NEMA NU4-2008 IQ phantom and tumor-bearing mouse scanned by Simens Invoen microPET. The simulated experiment and tumor-bearing mouse experiment showed that the algorithms using TV regularization provided superior qualitative and quantitative appearance compared with traditional VC and RL algorithms. When the mean intensity of the tumor increased by (10±1.8)%, the SD increase percentage was decreased from 49.98% to 14.26% and from 42.76% to 4.70%, suggesting the efficiency of the proposed algorithms for reducing PVEs in PET.

Vulvar intraepithelial neoplasia: a clinicopathologic study of twenty cases / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the clinical, pathological and immunohistochemical features of vulvar intraepithelial neoplasia (VIN).</p><p><b>METHODS</b>According to the 2004 modified terminology of International Society for the Study of Vulvovaginal Diseases (ISSVD), the cases were diagnosed as VIN from patients who had performed vulvar biopsy in Beijing Wuzhou Women's Hospital from February 2009 to December 2011, which were reclassified as usual VIN and differentiated VIN. The clinical and pathological studies were conducted respectively. MaxVision immunohistochemical staining was used to detect the expression of Ki-67, p16 and p53 proteins.</p><p><b>RESULTS</b>There were 20 cases of VIN in 237 patients, and the incidence of VIN was 8.4% in all of contemporary vulvar biopsy. In 17 cases of usual VIN, mean age was 29.6 years, the lesion typically presented with atypical cells involving almost all layers of the epithelium, which was equivalent to the high-grade squamous intraepithelial neoplasia of cervix. Immunohistochemistry for Ki-67 and p16 was strongly positive in usual VIN. High risk human papillomavirus (HPV) detection was also positive. The incidence of differentiated VIN was less than usual VIN, and there were only 3 cases in this study. In differentiated VIN, patients aged over 50 years, with mean of 53.7 years, and the lesion most commonly presented with lichen sclerosis background. There were epithelial thickening and extending, and parakeratosis, and atypia was strictly confined to the basal and parabasal layers of the epithelium where the cells enlarged with abundant eosinophilic cytoplasm, presented with prominent nucleoli, increased cellularity and abnormal keratinization. In differentiated VIN, p53 was strongly positive, Ki-67 and p16 immunohistochemical expression was confined to the basal layer only.</p><p><b>CONCLUSIONS</b>VIN is a precursor of invasive squamous cell carcinoma of the vulva. The modified terminology of ISSVD classifies VIN as high-grade lesions. Definitive pathological diagnosis of VIN plays an important role in its timely treatment and the prevention of vulvar carcinoma.</p>

Sparse angular CT projection onto convex set reconstruction using nonlocal means iterative modification / 南方医科大学学报

Based on the fact that nonlocal means (NL-means) filtered image can likely produce an acceptable priori solution, we propose a sparse angular CT projection onto convex set (POCS) reconstruction using NL-means iterative modification. The new reconstruction scheme consists of two components, POCS and NL-means filter. In each phase of the sparse angular CT iterative reconstruction, we first used POCS algorithm to meet the identity and non-negativity of projection data, and then performed NL-means filter to the image obtained by POCS method for image quality improvement. Simulation experiments showed that the proposed POCS scheme can significantly improve the quality of sparse angular CT image by suppressing the noise and removing the streak-artifacts.

Self-adapted segmentation of pulmonary nodule based on region growing / 南方医科大学学报

<p><b>OBJECTIVE</b>To improve the accuracy and efficiency of pulmonary nodule segmentation of thoracic CT image for computer-aided diagnostic (CAD) system, especially for those nodules adhering to the pleural or blood vessels.</p><p><b>METHODS</b>We proposed the automatic process of pulmonary nodule segmentation, and using region growing method based on the contrast and gradient, the pulmonary nodule images were acquired. A self-adapted morphologic segmentation algorithm was presented for the unsuccessful nodule segmentation using region growing.</p><p><b>RESULTS AND CONCLUSIONS</b>Experiments on clinical 2D pulmonary images showed that the solitary pulmonary nodules and those adhering to the pleural or blood vessels could all be segmented. This pulmonary nodule segmentation algorithm is feasible for automated segmentation of the thoracic CT images.</p>

Recent Progress on Rhamnolipid Produced from Fermentation of Waste Edible Oils / 微生物学通报

Although it is widely studied as a promising bio-surfactant,biosynthesis of Rhamnolipid has not been applied in large-scale due to its high production cost.As a cheap alternative carbon source,waste edible oils have been extensively studied for the production of rhamnolipid.This paper reviewed the recent re-search in this field,including the influence of various waste edible oils and production,chemical structure and properties of the produced rhamnolipids.With waste edible oils,the maximum production of rham-nolipids was reported to be 24.61 g/L.The lowest surface tension was 24 mN/m and the lowest CMC of the produced rhamnolipids was 40.19 mg/L.In addition,this paper also summarized the effect of various factors on the rhamnolipids biosynthesis,such as bacteria strains,nitrogen sources,trace minerals,dissolved oxygen,pH and fermentation conditions.Based on this,the key points of the mass production of rhamnolipids with waste edible oils were also discussed.

Isolation of Strains Producing Bio-demulsifiers and Comparison of Screening Methods / 微生物学通报

Four screening methods, colorimetric assay, blood-plate hemolysis method, surface tension activ- ity and oil spreading technique were introduced to isolate strains producing bio-demulsifiers from 6 different bacteria source samples. The results of various screening methods were evaluated in this paper. Seventeen demulsifying strains were obtained, which are qualified in demulsification test of kerosene model emulsions. Among them, 5 strains showed high demulsifying ability, achieving 70% plus demulsifying ratio within 24 hours. Petroleum-contaminated soil, excess sludge from biological process treating oilfield produced water and sludge from municipal wastewater treatment plant were the best among all tested sources. Due to the determination limit, the colorimetric assay and blood-plate hemolysis method are not competent to screen bio-demulsifiers strains. The measurement of surface tension and oil spreading method were easy but accu- rate methods to isolate bio-demulsifiers strains. Although demulsification test of model emulsion is an effec- tive technique to target strains with the capability of breaking emulsions, it is sophisticated and time-con- suming. Thus it is recommended to use surface tension and oil spreading methods in pre-screening and vali- date the results in demulsification test with kerosene model emulsions.