The value of postoperative HLA-DR expression and high mobility group box 1 level in predictive diagnosis of sepsis in percutaneous nephrolithotomy surgery.

OBJECTIVE: To analyze the value of postoperative human leukocyte antigen-DR (HLA-DR) expression and high mobility group box 1 (HMGB1) level in predictive diagnosis of postoperative sepsis for patients with percutaneous nephrolithotomy (PCNL) surgery. METHODS: The present prospective observational study included 387 patients with renal calculus who received PCNL surgery from January 2017 to October 2020 in our hospital. After exclusion criteria, 33 patients with sepsis and 78 patients with no sepsis remained. All patients received PCNL surgery. Sepsis definition is according to the third international consensus definitions for sepsis and septic shock (Sepsis-3). The data of the HMGB1, c-reactive protein (CRP), interleukin-6 (IL-6), procalcitonin (PCT) and HLA-DR expression were collected within admission and 24 h and 72 h after surgery. Postoperative HMGB1 levels and HLA-DR expression at 24 h and 72 h were respectively compared between the two groups using t test. ROC cure was used to analyze the value of postoperative HLA-DR expression and HMGB1 level in predictive diagnosis of sepsis. RESULTS: The positive rate of urine culture and the time of hospitalization time in patients with sepsis were significantly higher than those in patients with no sepsis. Sepsis group had higher levels of HMGB1 at post-24 h ((93.07 ± 11.37) ng/mL vs (75.41 ± 4.85) ng/mL), p < 0.05) and 72 h ((96.58 ± 12.12) ng/mL vs (81.16 ± 8.86) ng/mL), p < 0.05) than nosepsis group. Meanwhile, sepsis group had lower expression of HLA-DR at post-24 h ((50.01 ± 7.42) % vs (69.32 ± 10.58) %), p < 0.05) and 72 h ((54.85 ± 9.45) % vs (69.98 ± 11.00) %), p < 0.05) than non-sepsis group. ROC analysis showed that the HLA-DR expression at postoperative 24 h had highest predictive value in the diagnosis of sepsis, the AUC of HLA-DR was 0.934, cutoff value 56.19%, with sensitivity 89.7%, specificity 81.8%. CONCLUSION: Postoperative HLA-DR and HMGB1 can both be used as a predictive diagnosis of sepsis for patients with renal calculus received PCNL surgery. HighlightsSepsis group had higher levels of high mobility group box 1 at post-24 h and 72 h than nosepsis group.Sepsis group had lower expression of HLA-DR at post-24 h and 72 h than nosepsis group.Postoperative HLA-DR and HMGB1 can both be used as a predictive diagnosis of sepsis for patients with renal calculus received PCNL surgery.

Structural basis of a multi-functional deaminase in chlorovirus PBCV-1.

2-Deoxycytidylate deaminase (dCD) is a member of the zinc-dependent cytidine deaminase family features in its allosterically regulated mechanism by dCTP and dTTP. The large double-stranded DNA-containing chlorovirus PBCV-1 encodes a dCD family enzyme PBCV1dCD that was reported to be able to deaminize both dCMP and dCTP, which makes PBCV1dCD unique in the dCD family proteins. In this study, we report the crystal structure of PBCV1dCD in complex with dCTP/dCMP and dTTP/dTMP, respectively. We further proved the ability of PBCV1dCD in the deamination of dCDP, which makes PBCV1dCD a multi-functional deaminase. The structural basis for the versatility of PBCV1dCD is analyzed and discussed, with the finding of a unique Trp121 residue key to the deamination and substrate binding ability. Our findings may broaden the understanding of dCD family proteins and provide novel insights into the multi-functional enzyme.

Preoperative deep vein thrombosis in patients with cervical spondylotic myelopathy scheduled for spinal surgery.

INTRODUCTION: The prevalence of deep vein thrombosis (DVT) and its risk factors in patients with cervical spondylotic myelopathy (CSM) before spinal surgery are poorly understood. We investigated this association with a retrospective cross-sectional study. PATIENTS CONCERNS: The study cohort consisted of all consecutive patients with CSM who were scheduled for spinal surgery at our institution from 2013 to 2015. DVT was defined as an intraluminal filling defect in a lower extremity vein identified by Doppler ultrasonography. OUTCOMES: Of the 396 patients with CSM, 16 (4%) had DVT. Compared with patients without preoperative DVT, patients with preoperative DVT were older (62.75 ±â€Š8.79 vs 53.03 ±â€Š10.95 years, P = 0.001), had higher D-dimer concentrations (2.23 ±â€Š4.15 vs 0.43 ±â€Š0.90 mg/L, P = 0.04), had experienced longer duration of CSM (7.56 ±â€Š7.08 vs 4.01 ±â€Š6.37 months, P = 0.03), had lower Japanese Orthopaedic Association lower limb motor dysfunction scores (1.68 ±â€Š1.25 vs 2.54 ±â€Š0.91, P = 0.01), and had a history of ischemic cardiovascular events (33.3% vs 2.1%, P = 0.02). The area under the curve for the ability of D-dimer levels to predict DVT was 0.858 (95% confidence interval: 0.764-0.951; P < 0.0001). A D-dimer level of 0.54 mg/L detected DVT with a sensitivity and specificity of 87.5% and 83.2%, respectively. Abnormal D-dimer levels and ischemic cardiovascular events history were independent predictors of DVT. CONCLUSION: Patients with CSM who were scheduled for surgery often presented with preoperative DVT. Preoperative vascular screening should be considered for patients with CSM, especially for those who are older, have had longer duration of CSM, have poor lower limb mobility, and have a heart disease history. Inferior vena cava filter insertion and anticoagulation treatments should be considered for CSM patients with preoperative DVT.

Structural basis for the interaction of BamB with the POTRA3-4 domains of BamA.

In Escherichia coli, the Omp85 protein BamA and four lipoproteins (BamBCDE) constitute the BAM complex, which is essential for the assembly and insertion of outer membrane proteins into the outer membrane. Here, the crystal structure of BamB in complex with the POTRA3-4 domains of BamA is reported at 2.1 Šresolution. Based on this structure, the POTRA3 domain is associated with BamB via hydrogen-bonding and hydrophobic interactions. Structural and biochemical analysis revealed that the conserved residues Arg77, Glu127, Glu150, Ser167, Leu192, Leu194 and Arg195 of BamB play an essential role in interaction with the POTRA3 domain.

Citreoviridin Enhances Atherogenesis in Hypercholesterolemic ApoE-Deficient Mice via Upregulating Inflammation and Endothelial Dysfunction.

Vascular endothelial dysfunction and inflammatory response are early events during initiation and progression of atherosclerosis. In vitro studies have described that CIT markedly upregulates expressions of ICAM-1 and VCAM-1 of endothelial cells, which result from NF-κB activation induced by CIT. In order to determine whether it plays a role in atherogenesis in vivo, we conducted the study to investigate the effects of CIT on atherosclerotic plaque development and inflammatory response in apolipoprotein E deficient (apoE-/-) mice. Five-week-old apoE-/- mice were fed high-fat diets and treated with CIT for 15 weeks, followed by assay of atherosclerotic lesions. Nitric oxide (NO), vascular endothelial growth factor (VEGF) and endothelin-1 (ET-1) were detected in serum. Levels of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), VEGF, and ET-1 in plaque areas of artery walls were examined. NF-κB p65 expression and NF-κB activation in aorta also were assessed. CIT treatment significantly augmented atherosclerotic plaques and increased expressions of ICAM-1, VCAM-1, VEGF and ET-1 in aorta. Mechanistic studies showed that activation of NF-κB was significantly elevated by CIT treatment, indicating the effect of CIT on atherosclerosis may be regulated by activation of NF-κB.

Cytotoxic T lymphocyte-associated antigen 4 gene polymorphisms and autoimmune thyroid diseases: an updated systematic review and cumulative meta-analysis.

The association of the cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) gene and susceptibility to autoimmune thyroid diseases (AITDs) has been studied extensively. However, the results were not the same in different ethnic groups. We updated the meta-analysis of association of CTLA-4 gene polymorphisms with AITDs and summarized the results in specific ethnicity. The associations of A49G gene polymorphism with GD, A49G gene polymorphism with HT, CT60 gene polymorphism with GD, and CT60 gene polymorphism with HT were summarized based on the literatures published up to October 30, 2014, in English or Chinese languages. The participants involved in the studies of A49G with GD, A49G with HT, CT60 with GD, and CT60HT were 39004 subjects (in 51 studies), 13102 subjects (in 22 studies), 31446 subjects (in 22 studies), and 6948 subjects (in 8 studies), respectively. The pooled ORs of CTLA-4 gene polymorphisms with AITDs were larger than 1.00, and the 95% CIs of ORs were statistically significant among whole population analyses. However, the subgroup analysis demonstrated that pooled ORs of A49G polymorphisms with GD among Africans or Americans are less than 1.00. The accumulated evidence suggests that the G allele mutant of A49G and CT60 increased the risks of HT and GD.

Structure of Escherichia coli BamB and its interaction with POTRA domains of BamA.

In Escherichia coli, the BAM complex is essential for the assembly and insertion of outer membrane proteins (OMPs). The BAM complex is comprised of an integral ß-barrel outer membrane protein BamA and four accessory lipoproteins BamB, BamC, BamD and BamE. Here, the crystal structure of BamB is reported. The crystal of BamB diffracted to 2.0 Å with one monomer in the asymmetric unit and the structure is composed of eight-bladed ß-propeller motifs. Pull-down and Western blotting assays indicate that BamB interacts directly with the POTRA 1-3 domain of BamA and the C-terminal region of the POTRA 1-3 domain plays an important role in the interaction, while the POTRA 1-2 domain is not required for the interaction.

Structure of Escherichia coli BamD and its functional implications in outer membrane protein assembly.

The outer membrane protein complex (BAM complex) plays an important role in outer membrane protein (OMP) assembly in Escherichia coli. The BAM complex includes the integral ß-barrel protein BamA as well as four lipoproteins: BamB, BamC, BamD and BamE. One of these lipoproteins, BamD, is essential for the survival of Escherichia coli. The structure of BamD at 2.6 Šresolution shows that this lipoprotein is composed of ten α-helices that form five tetratricopeptide-repeat (TPR) motifs. The arrangement of the BamD motifs is similar to that in the periplasmic part of BamA. One of the ten α-helices, α10, which has been shown to be important for the assembly of the BAM complex, is located in the very C-terminal region of BamD. A deep groove between TPR domains 4 and 5 is also observed. This groove, as well as the surface around α10, may provide binding sites for other components of the BAM complex. The C-terminal region of BamD serves as a platform for interactions with other components of the BAM complex. The N-terminal region shares structural similarity to other proteins whose functions are related to assistance in or regulation of secretion. Therefore, this region is likely to play an important role in the insertion of other outer membrane proteins.

[The cytotoxic effect and injury mechanism of deoxynivalenol on articular chondrocytes in human embryo].

OBJECTIVE: This study was to explore the cytotoxic effect and the related injury mechanism of deoxynivalenol (DON) on articular chondrocytes in human embryo. METHODS: Articular cartilage cells were isolated from knees of human embryo and cultured in DMEM/F12 medium. The cells of the 4th generation were divided into five groups and incubated with varying concentrations of DON as the followings: control group and group with DON of 0.1, 0.2, 0.4, 1.0 µg/ml. The effects of DON were observed 72 hours after incubation. Cell apoptosis was assayed by flow cytometry (FCM) with Annexin V-FITC/PI staining; MMP-13 and PGE2 were detected by ELISA kits; NO was measured by Griess assay with spectrophotometer. Inducible nitric oxide synthase (iNOS) and collagen II in cells were detected by FCM. The expression levels of iNOS, mRNA and collagen II mRNA were measured with RT-PCR. RESULTS: The rates of cell apoptosis in DON groups were 6.78% - 19.05%, which were significantly higher than that in control (1.20%, F = 174.761, P < 0.05). The levels of NO in DON groups were 20.8 - 40.7 µmol/L, which were significantly higher than that in control (10.2 µmol/L, F = 91.966, P < 0.05). The levels of MMP-13 in DON groups were 0.25 - 0.56 µmol/L, which were significantly higher than that in control (0 µmol/L, F = 78.420, P < 0.05). The levels of PGE2 in DON groups were 3.2-20.6 µmol/L, which were significantly higher than that in control (11.6 µmol/L, F = 276.453, P < 0.05). The proportions of cells with positive iNOS in DON groups were 14.8% - 56.8% which were significantly higher than that in controls (7.1%, F = 214.614, P < 0.05). The proportions of cells with positive collagen II in groups with DON of 0.4 µg/ml and 1.0 µg/ml were 56.7% and 52.7%, which were significantly lower than that in control (62.2%, F = 5.134, P < 0.05). The relative absorbance values of iNOS mRNA in DON groups were 1.07 - 1.33, which were significantly higher than that in control (0.62, F = 8.358, P < 0.05). The levels of collagen II mRNA in groups with DON of 0.4 µg/ml and 1.0 µg/ml were 0.83 and 0.82, which were significantly lower than that in control (1.14, F = 7.887, P < 0.05). CONCLUSION: DON could promote anabolism of NO in articular cartilage cells by which up-regulated the expression of PGE2 and MMP-13, which both promoted resolution of articular cartilage matrix such as collagen II. DON induced apoptosis in articular cartilage cells.

High-resolution structure of a new crystal form of BamA POTRA4-5 from Escherichia coli.

In Escherichia coli, the BAM complex is employed to mediate correct folding of the outer membrane (OM) proteins into ß-barrels and their insertion into the OM. BamA, which is an essential component of the complex, consists of a C-terminal transmembrane region and five N-terminal polypeptide transport-associated (POTRA) domains. Although deletion studies have shown that each of the POTRA domains plays an important role in the process of BAM complex formation, only POTRA5 is essential for cell viability. Here, the crystal structure of POTRA4-5 has been determined to 1.50 Šresolution with an R factor of 14.7% and an Rfree of 18.9%.

Structure of orotate phosphoribosyltransferase from the caries pathogen Streptococcus mutans.

Orotate phosphoribosyltransferase (OPRTase) catalyzes the OMP-forming step in de novo pyrimidine-nucleotide biosynthesis. Here, the crystal structure of OPRTase from the caries pathogen Streptococcus mutans is reported at 2.4 A resolution. S. mutans OPRTase forms a symmetric dimer and each monomer binds two sulfates at the active sites. The structural symmetry of the sulfate-binding sites and the missing loops in this structure are consistent with a symmetric catalysis mechanism.

Crystal structures of Streptococcus mutans 2'-deoxycytidylate deaminase and its complex with substrate analog and allosteric regulator dCTP x Mg2+.

2'-Deoxycytidylate deaminase [or deoxycytidine-5'-monophosphate (dCMP) deaminase, dCD] catalyzes the deamination of dCMP to deoxyuridine-5'-monophosphate to provide the main nucleotide substrate for thymidylate synthase, which is important in DNA synthesis. The activity of this homohexameric enzyme is allosterically regulated by deoxycytidine-5'-triphosphate (dCTP) as an activator and by deoxythymidine-5'-triphosphate as an inhibitor. In this article, we report the crystal structures of dCMP deaminase from Streptococcus mutans and its complex with dCTP and an intermediate analog at resolutions of 3.0 and 1.66 A. The protein forms a hexamer composed of subunits adopting a three-layer alpha/beta/alpha sandwich fold. The positive allosteric regulator dCTP mainly binds at the interface between two monomers in a molar ratio of 1:1 and rearranges the neighboring interaction networks. Structural comparisons and sequence alignments revealed that dCMP deaminase from Streptococcus mutans belongs to the cytidine deaminase superfamily, wherein the proteins exhibit a similar catalytic mechanism. In addition to the two conserved motifs involved in the binding of Zn(2+), a new conserved motif, (G(43)YNG(46)), related to the binding of dCTP was also identified. N-terminal Arg4, a key residue located between two monomers, binds strongly to the gamma phosphate group of dCTP. The regulation signal was transmitted by Arg4 from the allosteric site to the active site via modifications in the interactions at the interface where the substrate-binding pocket was involved and the relocations of Arg26, His65, Tyr120, and Arg121 to envelope the active site in order to stabilize substrate binding in the complex. Based on the enzyme-regulator complex structure observed in this study, we propose an allosteric mechanism for dCD regulation.

Protein preparation, crystallization and preliminary X-ray crystallographic studies of Smu.1392c from Streptococcus mutans.

Smu.1392c is a protein with 158 residues of uncharacterized function. Bioinformatics studies predict it is a putative acetyltransferase. In order to identify its exact function via structural studies, Smu.1392c gene was amplified from Streptococcus mutans genomic DNA and cloned into expression vector PET28a. Smu.1392c was crystallized and diffracted to a resolution of 3 A in-house. The crystal belongs to R32 space group, with unit cell parameters a=b=229.10, c=63.49 A. There are 2 or 3 molecules in the asymmetric unit.

[Combination products: a new model of medical devices].

A combination product is a new model of the medical product that incorporates at least two of the regulated component categories of device, drug, or biological product into one product. It has become a new hot point within the development of devices and drugs, and has brought about a new opportunity for device and drug industries and a new challenge for administration too. In the paper, the properties of combination products are summed up and the impact on device and drug industries are discussed.