To better use the phase information to compensate the influence of blood flow, the phase unwrapping problem in susceptibility weighted imaging (SWI) is studied in this paper. In order to improve the accuracy of unwrapping, this paper proposes a magnitude image-guided phase unwrapping algorithm of SWI. The basic idea is as follows: (1) reduce the influence of noise by improving the rotational invariant non-local principal component analysis method (PRI-NL-PCA); (2) extract the corresponding solid region in the phase image to avoid the influence of the background noise on the phase unwrapping method; (3) use the phase compensation method to constrain the phase image reconstructed by the K-space. Finally, the reliability of the unwrapping method is evaluated by using four kinds of statistics as quantification index: the number, mean (M), variance (Var), and positive percentage (Pos) and negative percentage (Neg) of phasic error points. By comparing the simulated data with 226 sets of true head SWI data, the results show that the proposed algorithm has high accuracy compared with the classical branch cut method and the least squares method.
More and more medical devices can capture different features of human body and form three dimensional (3D) images. In clinical applications, usually it is required to fuse multiple source images containing different and crucial information into one for the purpose of assisting medical treatment. However, traditional image fusion methods are normally designed for two dimensional (2D) images and will lead to loss of the third dimensional information if directly applied to 3D data. Therefore, a novel 3D magnetic image fusion method was proposed based on the combination of newly invented beyond wavelet transform, called 3D band limited shearlet transformand (BLST), and four groups of traditional fusion rules. The proposed method was then compared with the 2D and 3D wavelet and dual-tree complex wavelet transform fusion methods through 4 groups of human brain T2* and quantitative susceptibility mapping (QSM) images. The experiments indicated that the performance of the method based on 3D transform was generally superior to the existing methods based on 2D transform. Taking advantage of direction representation, shearlet transform could effectively improve the performance of conventional fusion method based on 3D transform. It is well concluded, therefore, that the proposed method is the best among the methods based on 2D and 3D transforms.
Objective To explore the association between manganese superoxide dismutase (MnSOD) Val-9Ala polymorphism and breast cancer risk and to investigate the interaction with menopausal status by meta-analysis. Methods Such databases as The Cochrane Libtary (Issue1, 2010), Pubmed, CBM, CNKI and WanFang Data were searched from the date of their establishment to October, 2010, and the case-control studies of MnSOD Val-9Ala polymorphism and breast cancer risk were collected according to the inclusion and exclusion criteria. Then the quality of the included trials was assessed and meta-analysis was performed by RevMan 4.2.10 software. Results A total of 14 studies involving 17 842 patients were included. The results of meta-analyses showed no significant relation between MnSOD Val-9Ala polymorphism and the breast cancer susceptibility (Val/Ala vs. Val/Val: OR=1.04, 95%CI 0.93 to 1.17; Ala/Ala vs. Val/Val: OR=1.12, 95%CI 0.95 to 1.33; Ala/Ala vs. Val/Ala+Val/Val: OR=1.06, 95%CI 0.93 to 1.20; Val/Ala+ Ala/Ala vs. Val/Val: OR=1.06, 95%CI 0.94 to 1.10). However, in the subgroup analysis, the breast cancer risk significantly increased for premenopausal women (Val/Ala+Ala/Ala vs. Val/Val: OR=1.15, 95%CI 1.01 to1.31). Conclusion This meta-analysis suggests that the MnSOD Val-9Ala polymorphism is not significantly associated with the breast cancer susceptibility, but it may increase the risk of breast cancer in the presence of menopausal state.
Objective To summarize the advancement of hereditary thrombophilia. Methods Relevant literatures about hereditary thrombophilia published recently domestic and abroad were reviewed and analyzed. Results The hereditary risk factors of venous thromboembolism were different among different races. In western population, the main risk factors were activated protein C resistance (APC-R) and mutation of factor V Leiden, methylene tetrahydrofolate reductase polymorphism (C677T) and prothrombin G20210A. While in Chinese population, the disorder of protein C system and hyperhomocysteinemia were the major genetic risk factor. The existence of multiple genetic risk factors increased the incidence of primary and recurrent venous thromboembolism. Conclusion Further study on the relations between the hereditary risk factors and thrombophilia will be very important for prediction and prevention of the venous thromboembolism.
Objective To investigate the pathogen distribution and drug resistance in ICU patients, provide reference for prevention of severe infection and empirical antibacterial treatment. Methods The patients admitted in ICU between January 2013 and December 2014 were retrospectively analyzed. The pathogenic data were collected including bacterial and fungal culture results, the flora distribution and drug resistance of pathogenic bacteria. Results A total of 2088 non-repeated strains were isolated, including 1403 (67.2%) strains of Gram-positive bacteria, 496 (23.8%) strains of Gram-negative bacteria, and 189 (9.0%) strains of fungus. There were 1324 (63.42%) strains isolated from sputum or other respiratory specimens, 487 (23.33%) strains from blood specimens, 277 (13.27%) strains from other specimens. The bacteria included Acinetobacter baumannii (17.2%), Klebsiella pneumoniae (14.8%), Pseudomonas aeruginosa (9.9%), C. albicans (6.3%), E. coli (5.6%), E. cloacae (5.4%), Epidermis staphylococcus (5.0%) and Staphylococcus aureus (4.7%). There were 15 strains of penicillium carbon resistant enterobacteriaceae bacteria (CRE) accounting for 2.3%, including 5 strains of Pneumonia klebsiella, 4 strains of E. cloacae. In 117 strains of E. coli, drug-resistant strains accounted for 86.4% including 85.5% of multiple drug-resistant strains (MDR) and 0.9% of extremely-drug resistant (XDR) strains. In 359 strains of Acinetobacter baumannii, drug-resistant strains accounted for 75.2% including 72.1% of XDR strains and 3.1% of MDR strains. MDR strains accounted for 10.6% in Pseudomonas aeruginosa. Detection rate of methicillin resistant Staphylococcus aureus (MRSA) and methicillin resistant coagulase-negative Staphylococci (MRCNS) was 49.0% and 95.5%, respectively. There were 4 strains of vancomycin resistant Enterococcus faecalis. There were 131 (69.3%) strains of C. albicans, 23 (12.2%) strains of smooth candida. C. albicans was sensitive to amphotericin and 5-fluorine cytosine, and the resistance rate was less than 1% to other antifungle agents. The resistance rate of smooth ball candida was higher than C. albicans and nearly smooth candida, but still less than 15%. Conclusions The predominant pathogens in ICU was gram-negative bacteria. The top eight pathogenic bacteria were Acinetobacter baumanni, Klebsiella pneumoniae, Pseudomonas aeruginosa, C. albicans, E. coli, E. cloacae, Epidermis staphylococcus and S. aureus. Sputum and blood are common specimens. CRE accounts for 2.3%. Drug-resistant strains are most common in E. coli mainly by MDR, followed by Acinetobacter baumannii mainly by XDR, and least in Pseudomonas aeruginosa. C. albicans is the most common fungus with low drug resitance.
ObjectiveTo summarize functions and mechanisms of poly ADP-ribose polymerase (PARP) inhibitors and its application in germline BRCA mutated breast cancer.MethodThe literatures about the PARP inhibitors and their applications in the treatment of germline BRCA mutated breast cancer at home and abroad in recent years were collected to make a review.ResultsAs a DNA repair enzyme, the PARP played an important role in the DNA repair pathway. Based on this mechanism, the PARP inhibitors had been developed and widely used in the clinic. On the other hand, the previous studies had shown that the PARP inhibitors marked the synthetic lethal effect in the cancers with homologous recombination deficiency mechanism. By inhibiting the PARP activity in the tumor cells with BRCA mutation, all the DNA damage repair pathways were blocked, which could induce the cell apoptosis or increase the sensitivity of tumor cells to chemoradiotherapy, resulting in the cell death.ConclusionIn patients with germline BRCA mutated breast cancer, PARP inhibitors can selectively kill breast cancer cells and show a high potential for individualized treatment.
Antimicrobial resistance is a rigorous health issue around the world. Because of the short turn-around-time and broad pathogen spectrum, culture-independent metagenomic next-generation sequencing (mNGS) is a powerful and highly efficient tool for clinical pathogen detection. The increasing question is whether mNGS is practical in the prediction of antimicrobial susceptibility. This review summarizes the current mNGS-based antimicrobial susceptibility testing technologies. The critical determinants of mNGS-based antibacterial resistance prediction have been comprehensively analyzed, including antimicrobial resistance databases, sequence alignment tools, detection tools for genomic antimicrobial resistance determinants, as well as resistance prediction models. The clinical challenges for mNGS-based antibacterial resistance prediction have also been reviewed and discussed.
Objective To analyze the human leukocyte antigen (HLA) gene polymorphism and haplotype frequency and distribution in Han patients with end stage renal disease (ESRD) in Sichuan province, and explore the correlation of HLA gene polymorphism and haplotype with the susceptibility to ESRD in Sichuan Han patients. Methods Polymerase chain reaction-sequence specific oligonucleotide probe hybridization typing technique was used to detect the HLA-A, -B, -DRB1, and -DQB1 genotypes of Han patients with ESRD and healthy participants. The allele and haplotype frequencies in the ESRD group and the control group were analyzed using SPSS 25.0 and Arlequin 3.5.2.2 softwares. Results A total of 756 ESRD patients and 1118 healthy participants were enrolled. In the four loci of HLA-A, -B, -DRB1, and -DQB1, the frequency of HLA-B*39 allele in the ESRD group was higher than that in the control group [3.37% vs. 2.19%; χ2=4.850, P=0.028, odds ratio (OR)=1.558, 95% confidence interval (CI) (1.047, 2.319)], the frequency of HLA-DQB1*06 allele in the ESRD group was lower than that in the control group [17.39% vs. 21.20%; χ2=8.264, P=0.004, OR=0.783, 95%CI (0.662, 0.925)], and the frequency of HLA-DQB1*04 allele in the ESRD group was higher than that in the control group [7.41% vs. 5.46%; χ2=5.867, P=0.015, OR=1.386, 95%CI (1.063, 1.807)]. The frequencies of 10 haplotypes, including HLA-A*11-B*39, HLA-DRB1*15-DQB1*06, and HLA-DRB1*04-DQB1*04, were significantly different between the ESRD group and the control group (P<0.05), among which 9 haplotypes were possibly susceptible to ESRD and 1 haplotype was possibly protective. Conclusions HLA gene polymorphism is closely related to the susceptibility to ESRD. HLA-B*39 and HLA-DQB1*04 may be susceptible genes for ESRD in Sichuan Han patients, while HLA-DQB1*06 may be a protective gene. In addition, 10 HLA haplotypes are possibly associated with the susceptibility to ESRD in Sichuan Han patients.
ObjectiveTo understand the drug resistance of Mycobacterium tuberculosis complex in West China Hospital, Sichuan University, analyze its drug resistance characteristics, and provide reference for the monitoring of drug-resistant tuberculosis.MethodsFrom January 2016 to March 2018, Mycobacterium tuberculosis drug susceptibility testing kit was used to detect the drug susceptibility of Mycobacterium tuberculosis culture-positive strains in Department of Laboratory Medicine, West China Hospital, Sichuan University. The tested drugs included four of the first-line anti-tuberculosis drugs: rifampicin, isoniazid, ethambutol, and streptomycin, and ten of the second-line anti-tuberculosis drugs: capreomycin, ofloxacin, ethionamide, p-aminosalicylic acid, levofloxacin, moxifloxacin, rifabutin, amikacin, kanamycin, and chlorine phenazine.ResultsA total of 130 patients (130 strains) were enrolled, including 82 newly diagnosed patients (82 strains) and 48 re-treated patients (42 strains). The drug resistance rate of the 130 patients was 37.69%. The drug resistance rate of the newly diagnosed patients (28.05%) was significantly lower than that of the re-treated patients (54.17%), and there was a statistical difference (χ2=8.794, P=0.003). The multi-drug resistance rate of the newly diagnosed patients (6.10%) was significantly lower than that of the re-treated patients (25.00%), and the difference was statistically significant (χ2=9.517, P=0.002). The resistance rate of isoniazid, rifampicin, and streptomycin in newly diagnosed patients (23.17%, 8.54%, and 7.32%, respectively) were significantly lower than those in the re-treated patients (45.83%, 41.67%, and 29.17%, respectively), and the differences were statistically significant (P<0.05). The resistance rate of ofloxacin, moxifloxacin, rifabutin and ethionamide in the newly diagnosed patients (9.76%, 8.54%, 7.31%, and 4.88%, respectively) were significantly lower than those in the re-treated patients (39.58%, 27.08%, 25.00%, and 22.92%, respectively), and the differences were statistically significant (P<0.05).ConclusionIt is necessary to strengthen the standardized treatment of patients with newly diagnosed tuberculosis, increase the treatment and management of re-treated tuberculosis patients, and prevent the generation and spread of drug-resistant patients, especially multidrug-resistant patients.
ObjectiveThrough Sequenom iPEX system analyzed the genetic susceptibility in patients with Medial temporal lobe epilepsy (MTLE) which screening hyperpolarization-activated cyclic nucleotide gated channel (HCN) subunit HCN1 and HCN2 single nucleotide polymorphism blood samples. MethodsPatients with epilepsy who were diagnosed MTLE in our epileptic clinic from December 2013 to April 2016 were included in this study, total 143 cases. Healthy volunteers who received annual physical checkups were recruited to serve as controls total 120 cases. The group enter criterion according to a 2004 ILAE report mainly:①12~55 years old; ②attack forms:partial onset seizures or secondary tonic-closure-clonus attack, a common onset symptoms such as stomach gas rise feeling, sense of deja vu, automatism etc.; ③with or without febrile convulsions history; ④EEG displayed unilateral or bilateral temporal spike, sharp slow wave, or their spines slow-wave sample such as epilepsy wave; ⑤head MRI displayed hippocampal sclerosis. Exclusion criteria:①tumors; ②head MRI display focal cortical dysplasia (FCD). Using sequenom iPLEX technology platform to detect all the object of study of gene polymorphism sites total ten sites. All statistical tests were conducted using SPSS version 16.0. Resultsall sites fulfilled Hardy-Weinberg genetic balance. The results showed that HCN1 rs17344896 C/T, rs6451973 A/G and HCN2 rs12977194 A/G three polypeptide sites associated with MTLE, with statistical differences(P < 0.05). ConclusionHCN1 and HCN2 genetic suscepibility is one of possible mechanism of MTLE.