[Bioinformatics analysis in metagenomic next-generation sequencing of pathogenic microorganisms: current status and challenges].

The clinical application of metagenomic next-generation sequencing (mNGS) in the diagnosis of unknown pathogenic infections and critical infections has become increasingly valuable. Due to the huge volume of mNGS data and the complexity of clinical diagnosis and treatment, mNGS has difficulties in data analysis and interpretation in practical application. Therefore, in the process of clinical practice, it is crucial to grasp the key points of bioinformatics analysis and establish a standardized bioinformatics analysis process, which is an important step in the transformation of mNGS from laboratory to clinic. At present, bioinformatics analysis of mNGS has made great progress, but with the high requirements of clinical standardization of bioinformatics analysis and the development of computer technology, bioinformatics analysis of mNGS is also facing new challenges. This article mainly elaborates on quality control, and identification and visualization of pathogenic bacteria.

[Safety and efficacy evaluation of laparoscopic and open hepatectomy for hepatolithiasis: a propensity score matched analysis].

Objective: To compare the safety and efficacy of laparoscopic and open hepatectomy for hepatolithiasis. Methods: Between January 2014 and May 2020, the clinicopathological data of 254 patients with hepatolithiasis who underwent laparoscopic or open hepatectomy at the First Department of Hepatobiliary Surgery,Affiliated Hospital of North Sichuan Medical College were collected retrospectively. There were 74 males and 180 females with age of (56±8) years (range: 38 to 77 years). Of the 254 patients, 162 underwent laparoscopic surgery (laparoscopic group) and 92 underwent open surgery (open group). Propensity score matching(PSM) was performed to match baseline characteristics of the two groups,and then the perioperative results and follow-up efficacy were compared between the two groups. The t-test, Mann-Whitney U test, χ2 test or Fisher's exact probability method was used to compare the perioperative data and follow-up results of the two groups after matching, respectively. Results: Each group had 63 patients after PSM with well-balanced baseline characteristics. There was no statistic difference in the type of hepatectomy,combined common bile duct exploration rate,T tube drainage placement rate,operation time,intraoperative transfusion rate,intraoperative accidental injury rate,initial and final stone clearance rate,and stone recurrence rate between the two groups. However,compared with the open hepatectomy group, the laparoscopic group had significantly lower intraoperative blood loss (M(IQR))(300(175)ml vs. 350(145)ml, Z=3.227,P=0.001),shorter postoperative hospital stay((10.6±4.1)days vs. (14.0±4.0)days,t=4.634,P<0.01),shorter time to postoperative oral intake ((1.8±1.1)days vs. (2.9±1.6)days, t=4.556, P<0.01), and lower postoperative complication rate (25.4%(16/63) vs. 49.2%(31/63), χ²=7.635, P=0.006). Conclusion: Laparoscopic hepatectomy is safe and effective for hepatolithiasis with the advantages of less intraoperative blood loss,lower postoperative complications and faster postoperative recovery.

[CCAAT/enhancer binding protein δ inhibits invasion and metastasis of liver cancer by regulating M1 type macrophages polarization].

Objective: To explore the regulation of macrophage polarization and its effects on liver cancer invasion, metastasis and apoptosis by CCAAT/enhancer binding protein δ (CEBPD). Methods: THP-1 stable transfected cells with knockdown CEBPD (shCEBPD) and negative control shNC were constructed by lentviral transfection technique. THP-1 transfected cells were induced into macrophages, lipopolysaccharide (LPS) and interferon γ(IFNγ) by phorbol 12-tetradecanoate 13-acetate (PMA), and then the polarized macrophages were further induced to M1 type. The quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect M1 type macrophage related interleukin 1ß (IL-1ß) genes, IL-6, tumor necrosis factor α (TNFα), and inducible nitric oxide synthase (iNOS) mRNA expression level. Flow cytometry was used to detect M1 macrophage-specific surface marker CD80 expression levels. M1-induced macrophages were co-cultured with liver cancer MHCC97H cells using Transwell non-contact small sized co-culture dishes. MHCC97H cells invasion and metastasis were detected by Transwell and scratch assay under co-culture conditions, and the MHCC97H cells apoptosis was detected by flow cytometry. Results: The mRNA expression levels of M1 macrophage marker genes iNOS, TNFα, IL-6 and IL-1ß in THP-1 derived macrophages were decreased after CEBPD knockdown. M1 macrophage-specific surface marker CD80 expression levels were decreased (23.7% ± 2.1% and 62.5% ± 2.0%, t = 9.58, P < 0.05). THP-1 were co-cultured with MHCC97H in shCEBPD and shNC group, respectively. Compared with shNC group, the invasion [(158.0 ± 3.5) and (75.0 ± 4.5), t = 39.87, P < 0.01] and metastatic ability (54.6% ± 1.5% and 24.3% ± 1.0%, P < 0.01) of MHCC97H cells co-cultured in shCEBPD group were stronger and the apoptosis rate was reduced [(9.4% ± 1.0%) vs. (23.7% ± 1.2%), t = 12.68, P < 0.01]. Conclusion: CEBPD can inhibit the invasion and metastasis and increase the apoptosis by amplifying M1 type macrophages polarization in liver cancer cells.

[A multicenter clinical analysis of short-term efficacy of laparoscopic radical resection of hilar cholangiocarcinoma].

Objective: To investigate the feasibility and safety of laparoscopic radical resection of hilar cholangiocarcinoma at multiple centers in China. Methods: Between December 2015 and August 2019, the clinical data of 143 patients who underwent LRHC in Affiliated Hospital of North Sichuan Medical College, Second Hospital of Hebei Medical University, Affiliated Hospital of Xuzhou Medical University, Affiliated Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Hunan Provincial People's Hospital, the First Hospital Affiliated to Army Medical University, Sir Run Run Shaw Hospital Affiliated to Medical College of Zhejiang University, West China Hospital of Sichuan University, Nanfang Hospital of Southern Medical University and the First Affiliated Hospital of Chongqing Medical University were collected prospectively. There were 92 males and 51 females with age of (64±11) years (range: 53 to 72 years). Bismuth type: type I, 38 cases (26.6%), type Ⅱ, 19 cases (13.3%), type Ⅲa, 15 cases (10.5%), type Ⅲb, 28 cases (19.6%) and type Ⅳ, 43 cases (30.0%). The patients within the first 10 operation cases in each operation time (the first 10 patients in each operation team) were divided into group A (77 cases), and the patients after 10 cases in each operation time were classified as group B (66 cases); the cases with more than 10 cases in the center were further divided into group A(1) (116 cases), and the center with less than 10 cases was set as group A(2) (27 cases). T test or Wilcoxon test was used to compare the measurement data between groups, and the chi square test or Fisher exact probability method was used to compare the counting data between groups. Kaplan Meier curve was used for survival analysis. Results: All patients successfully completed laparoscopic procedure. The mean operation time was (421.3±153.4) minutes (range: 159 to 770 minutes), and the intraoperative blood loss was 100 to 1 500 ml (median was 300 ml) .Recent post-operative complications contained bile leakage, abdominal bleeding, abdominal infection, gastrointestinal bleeding, and delay gastric emptying, pulmonary infection, liver failure, et al.The post-operative hospital stay was (15.9±9.2) days. The operation time in group B was relatively reduced ( (429.5±190.7)minutes vs. (492.3±173.1)minutes, t=2.063, P=0.041) and the blood loss (465 ml vs. 200 ml) was also reduced (Z=2.021, P=0.043) than that in group B. The incidence of postoperative biliary fistula and lung infection in patients in group A was significantly higher than that in group B (χ(2)=4.341, 0.007; P=0.037, 0.047) .Compared with group A(2), the operation time in group A(1) was relatively reduced( (416.3±176.5)minutes vs. (498.1±190.4)minutes, t=2.136, P=0.034) , the incidence of bile leakage and abdominal cavity infection in group A(1) was lower than that in group A(2) (χ(2)=7.537, 3.162; P=0.006, 0.046) . Kaplan Meier survival curve showed that the difference of short-term survival time between group A and group B was statistically significant (P<0.05) . Conclusions: The completion of laparoscopic hilar cholangiocarcinoma radical surgery is based on improved surgical skills, and proficiency in standardized operation procedures.It is feasible for laparoscopic radical resection of hilar cholangiocarcinoma to well experienced surgeon with cases be strictly screened, but it is not recommended for widespread promotion at this exploratory stage.

[Expression and mechanism of Twist2 in glioma].

Objective: To investigate the significance of Twist2 in glioma and whether it is involved in the malignant transformation of glioma by epithelial-mesenchymal transition (EMT). Methods: Using immunohistochemical method detected the expression level of Twist2 in 60 cases of gliomas (including WHO grades Ⅱ, Ⅲ and Ⅳ, each for 20 cases) and 20 cases of non-tumor brain tissues. Real-time fluorescence quantitative PCR and Western blot were used to detect the expression level of Twist2 mRNA and protein in 61 cases of fresh glioma tissue (WHO grade Ⅱ 16 cases, Ⅲ 21 cases, Ⅳ 24 cases) and 12 cases of adjacent tissues, and the expression levels of E-cadherin, N-cadherin and vimentin were also investigated in fresh glioma tissue. Results: Immunohistochemistry results showed that the percentages of Twist2 expression in glioma was 90%(54/60) compared with 30%(6/20) in non-tumor brain tissues(P<0.01). The percentages of Twist2 expression were 75% (15/20), 95% (19/20), and 100% (20/20) in the WHO gradesⅡ, Ⅲ and Ⅳ gliomas, respectively. WHO grades Ⅳ and Ⅲ were significantly higher than that of WHO grade Ⅱ (P<0.01). There was no significant difference between WHO grade Ⅳand WHO Ⅲ glioma (P>0.05). Real-time fluorescence quantitative PCR and Western blot showed that the expression level of Twist 2 in gliomas was significantly higher than that in para-cancerous tissues (P<0.01), and those in WHO grades Ⅳ and Ⅲ gliomas were significantly higher than that in WHO grade Ⅱ glioma (P<0.01). There was no significant difference between WHO grade Ⅳand grade Ⅲ glioma (P>0.05). Detection of key protein expression in EMT by Western blot displayed that the expression of E-cadherin was negatively associated with Twist2 in glioma (r=-0.972, P<0.01). The expression of N-cadherin and vimentin was positively associated with Twist2 in glioma(r=0.971, P<0.01; r=0.968, P<0.01). Conclusions: The expression of Twist2 in human glioma is positively correlated with the malignant grade of glioma, which may be involved in the malignant progression of glioma by EMT.

Morphology changes of nanocrystals induced by a small amount of water in the composite-hydroxide-mediated approach.

The influence of water on morphology and structure of nanomaterials synthesized by the composite-hydroxide-mediated (CHM) approach has been systematically investigated. A small amount of water would affect the morphology and size, while a large amount of water would affect not only the morphology, but the structure of nanomaterials. The experimental results indicate that the nanocrystals prefer anisotropic growth and form more regular shape by the CHM route to hydrothermal synthesis.