Predictive value of procalcitonin level for pharyngocutaneous fistula after laryngectomy.

BACKGROUND: Pharyngocutaneous fistula (PCF) is among the most common postoperative infective complications following laryngectomy. Its diagnosis is often late and identified only after the formation of an abnormal, bacterial infection-harboring fistula track between the pharynx and the skin. This study was aimed at determining whether procalcitonin (PCT), white blood cell count (WBC), C-reactive protein (CRP), and neutrophil percentage are good predictors of PCF. METHODS: We prospectively analysed 65 consecutive patients undergoing total laryngectomy. Clinicodemographic, surgical, and body mass index data were collected. Data on serum levels of PCT, WBC, CRP, and neutrophils were obtained before surgery and on postoperative days 2, 4, 6, 8, and 10 by immunofluorescence, immune turbidimetry, and automatic blood analyzer. The area under the receiving operating characteristic (ROC) curve was calculated for each marker. RESULTS: There were 65 patients with a mean age of 60.34 years. The PCF occurrence rate was 18.46 % (12/65). Serum levels of PCT and CRP determined on postoperative day 2, 4, 6, 8, and 10 after surgery were higher in patients with PCF (P < 0.01). PCT level was identified as a good predictor area under the curve (AUC) > 0.800 on postoperative days 2, 4, and 6. Considering the sensitivity and specificity, the best combination was PCT on postoperative days 4, which with a cutoff level of 0.12 µg/L showed 91.67 % sensitivity and 100 % specificity. CONCLUSIONS: Procalcitonin can predict PCF following laryngectomy. PCT > 0.12 µg/L on postoperative day 4 was a reliable predictor of PCF. This may help guide postoperative antibiotic management.

The mechanism of the receptors for advanced glycation end products affecting pericyte detachment from blood vessels after traumatic brain injury / 西安交通大学学报(医学版)

【Objective】 To observe the reactive change of cortical perivascular cells after craniocerebral injury and explore its mechanism. 【Methods】 The controllable cortical impact animal model was used to simulate craniocerebral injury, the expressions of cortical pericyte markers at different time points after trauma were studied by Western blotting, and the biological behavior of vascular pericytes after craniocerebral injury was determined by transmission electron microscopy. Post-traumatic high mobility group box 1 (HMGB1), receptor for advanced glycation end product (RAGE), and nuclear factor κB (NF-κB) were detected by Western blotting. The experimental animals were divided into FPS-ZM1 (a specific RAGE receptor blocker) injection group and wild-type group. Wet and dry brain weight and transmission electron microscopy were used to study the post-traumatic effects of HMGB1-RAGE on pericytes. The primary mouse brain microvascular pericytes were cultured and supplemented with HMGB1 recombinant protein; the cultured pericytes supplemented with FPS-ZM1 were used as the control to explore the effect of HMGB1-RAGE pathway on vascular pericytes in vitro. 【Results】 The expression levels of early post-traumatic cortical pericyte markers platelet-derived growth factor receptor beta (PDGFR-β) and NG2 proteoglycan (NG2) decreased (PDGFR-β, Control vs. CCI 3D P<0.05; NG2, Control vs. CCI 6H P<0.05; Control vs. CCI 1D P<0.05). We found that pericytes were detached from blood vessels, accompanied by local blood-brain barrier opening. The expression of HMGB1-RAGE-NF-κB signaling pathway was increased in the early cortex after trauma (HMGB1, Control vs. CCI 6H P<0.05, Control vs. CCI 1D P<0.05; RAGE, Control vs. CCI 6H P<0.05, Control vs. CCI 1D P<0.05, Control vs. CCI 3D P<0.05, Control vs. CCI 5D P<0.05, Control vs. CCI 7D P<0.05; NF-κB, Control vs. CCI 6H P<0.05, Control vs. CCI 1D P<0.05). After blocking the binding of RAGE with the ligand, cortical edema was reduced (CCI 6H P<0.05, CCI 1D P<0.05), and neurovascular unit damage was reduced. HMGB1 recombinant protein could increase the migration ability of cultured pericytes (Control vs. HMGB1 P<0.05, Control vs. HMGB1+FPS-ZM1 P<0.05), and could be reversed by FPS-ZM1 (HMGB1 vs. HMGB1+FPS-ZM1 P<0.05). 【Conclusion】 High-level HMGB1 after traumatic brain injury mediates pericytes’ detachment from blood vessels through RAGE on pericytes and leads to the occurrence of local cerebral edema.

Value of blood lipid parameters in predicting the progression of HBV-related acute-on-chronic pre-liver failure / 临床肝胆病杂志

Objective To investigate the difference in blood lipid parameters between acute-on-chronic pre-liver failure (pre-ACLF) and acute-on-chronic liver failure (ACLF) and the risk factors for disease progression. Methods A retrospective analysis was performed for the related data of 118 patients with ACLF (ACLF group) and 44 patients with pre-ACLF (pre-ACLF group) who were treated in The General Hospital of Western Theater Command from January 2012 to December 2020, including baseline age, albumin, creatinine, routine blood test results, and blood lipids. The independent samples t -test was used for comparison between normally distributed continuous data; and the Mann-Whitney U test was used for comparison between non-normally distributed continuous data; the chi-square test was used for comparison of categorical data between groups. A binary logistic regression analysis was used for multivariate analysis to identify independent predictive factors. The receiver operating characteristic (ROC) curve was used to compare the sensitivity and specificity of related indicators, and Youden index was used to calculate cut-off values. Results Compared with the pre-ACLF group, the ACLF group had significantly lower levels of total cholesterol (TC)[2.02(1.56-2.37) mmol/L vs 3.01(2.57-3.66) mmol/L, Z =5.411, P 0.05). The logistic regression analysis showed that TC (odds ratio [ OR ]=0.003, 95% confidence interval [ CI ]: 0.000-0.068, P < 0.05), LDL ( OR =61.901, 95% CI : 3.354-1142.558, P < 0.05), and WBC ( OR =3.175, 95% CI : 1.097-9.185, P < 0.05) had an independent predictive value, and the ROC analysis showed that the area under the ROC curve of TC was 0.852, the sensitivity of LDL was 0.887, and TC had the best specificity of TC was 0.840. Conclusion There are reductions in blood lipid parameters in the progression from pre-ACLF to ACLF, suggesting that clinicians should pay attention to the changes in lipids in the pre-ACLF stage and adjust the nutritional regimen in a timely manner.

Towards increased accuracy and reproducibility in SARS-CoV-2 next generation sequence analysis for public health surveillance

During the COVID-19 pandemic, SARS-CoV-2 surveillance efforts integrated genome sequencing of clinical samples to identify emergent viral variants and to support rapid experimental examination of genome-informed vaccine and therapeutic designs. Given the broad range of methods applied to generate new viral genomes, it is critical that consensus and variant calling tools yield consistent results across disparate pipelines. Here we examine the impact of sequencing technologies (Illumina and Oxford Nanopore) and 7 different downstream bioinformatic protocols on SARS-CoV-2 variant calling as part of the NIH Accelerating COVID-19 Therapeutic Interventions and Vaccines (ACTIV) Tracking Resistance and Coronavirus Evolution (TRACE) initiative, a public-private partnership established to address the COVID-19 outbreak. Our results indicate that bioinformatic workflows can yield consensus genomes with different single nucleotide polymorphisms, insertions, and/or deletions even when using the same raw sequence input datasets. We introduce the use of a specific suite of parameters and protocols that greatly improves the agreement among pipelines developed by diverse organizations. Such consistency among bioinformatic pipelines is fundamental to SARS-CoV-2 and future pathogen surveillance efforts. The application of analysis standards is necessary to more accurately document phylogenomic trends and support data-driven public health responses.

In Vitro Selection of Remdesivir-Resistant SARS-CoV-2 Demonstrates High Barrier to Resistance.

In vitro selection of remdesivir-resistant SARS-CoV-2 revealed the emergence of a V166L substitution, located outside of the polymerase active site of the nsp12 protein, after 9 passages. V166L remained the only nsp12 substitution after 17 passages at a final concentration of 10 {micro}M RDV, conferring a 2.3-fold increase in EC50. When V166L was introduced into a recombinant SARS-CoV-2 virus, a 1.5-fold increase in EC50 was observed, indicating a high in vitro barrier to RDV resistance.

Remdesivir and GS-441524 retain antiviral activity against Delta, Omicron, and other emergent SARS-CoV-2 variants

Genetic variation of SARS-CoV-2 has resulted in the emergence and rapid spread of multiple variants throughout the pandemic, of which Omicron is currently the predominant variant circulating worldwide. SARS-CoV-2 variants of concern or interest (VOC/VOI) have evidence of increased viral transmission, disease severity, or decreased effectiveness of vaccines and neutralizing antibodies. Remdesivir (RDV, VEKLURY(R)) is a nucleoside analog prodrug and the first FDA-approved antiviral treatment of COVID-19. Here we present a comprehensive antiviral activity assessment of RDV and its parent nucleoside, GS-441524, against 10 current and former SARS-CoV-2 VOC/VOI clinical isolates by nucleoprotein ELISA and plaque reduction assay. Delta and Omicron variants remained susceptible to RDV and GS-441524, with EC50 values 0.31 to 0.62-fold of those observed against the ancestral WA1 isolate. All other tested variants exhibited EC50 values ranging from 0.15 to 2.3-fold of the observed EC50 values against WA1. Analysis of nearly 6 million publicly available variant isolate sequences confirmed that Nsp12, the RNA-dependent RNA polymerase (RdRp) target of RDV and GS-441524, is highly conserved across variants with only 2 prevalent changes (P323L and G671S). Using recombinant viruses, both RDV and GS-441524 retained potency against all viruses containing frequent variant substitutions or their combination. Taken together, these results highlight the conserved nature of SARS-CoV-2 Nsp12 and provide evidence of sustained SARS-CoV-2 antiviral activity of RDV and GS-441524 across the tested variants. The observed pan-variant activity of RDV supports its continued use for the treatment of COVID-19 regardless of the SARS-CoV-2 variant.

Distinct genetic determinants and mechanisms of SARS-CoV-2 resistance to remdesivir

The nucleoside analog remdesivir (RDV) is an FDA-approved antiviral for the treatment of SARS- CoV-2 infections, and as such it is critical to understand potential genetic determinants and barriers to RDV resistance. In this study, SARS-CoV-2 was subjected to 13 passages in cell culture with increasing concentrations of GS-441524, the parent nucleoside of RDV. At passage 13 the RDV resistance of the lineages ranged from 2.7-to 10.4-fold increase in EC50. Sequence analysis of the three lineage populations identified non-synonymous mutations in the nonstructural protein 12 RNA-dependent RNA polymerase (nsp12-RdRp): V166A, N198S, S759A, V792I and C799F/R. Two of the three lineages encoded the S759A substitution at the RdRp Ser759-Asp-Asp active motif. In one lineage, the V792I substitution emerged first then combined with S759A. Introduction of the S759A and V792I substitutions at homologous nsp12 positions in viable isogenic clones of the betacoronavirus murine hepatitis virus (MHV) demonstrated their transferability across CoVs, up to 38-fold RDV resistance in combination, and a significant replication defect associated with their introduction. Biochemical analysis of SARS-CoV-2 RdRp encoding S759A demonstrated a [~]10- fold decreased preference for RDV-triphosphate (RDV-TP) as a substrate, while nsp12-V792I diminished the UTP concentration needed to overcome the template-dependent inhibition associated with RDV. The in vitro selected substitutions here identified were rare or not detected in the >6 million publicly available nsp12-RdRp consensus sequences in the absence of RDV selection. The results define genetic and biochemical pathways to RDV resistance and emphasize the need for additional studies to define the potential for emergence of these or other RDV resistance mutations in various clinical settings. One Sentence SummarySARS-CoV-2 develops in vitro resistance to remdesivir by distinct and complementary mutations and mechanisms in the viral polymerase

Genetic Conservation of SARS-CoV-2 RNA Replication Complex in Globally Circulating Isolates from Humans and Minks Predicts Minimal Pre-Existing Resistance to Remdesivir

Remdesivir (RDV) exhibits potent antiviral activity against SARS-CoV-2 and is currently the only drug approved for the treatment of COVID-19. However, little is currently known about the potential for pre-existing resistance to RDV and the possibility of SARS-CoV-2 genetic diversification that might impact RDV efficacy as the virus continue to spread globally. In this study, >90,000 SARS-CoV-2 sequences from globally circulating clinical isolates, including sequences from recently emerged United Kingdom and South Africa variants, and >300 from mink isolates were analyzed for genetic diversity in the RNA replication complex (nsp7, nsp8, nsp10, nsp12, nsp13, and nsp14) with a focus on the RNA-dependent RNA polymerase (nsp12), the molecular target of RDV. Overall, low genetic variation was observed with only 12 amino acid substitutions present in the entire RNA replication complex in [≥]0.5% of analyzed sequences with the highest overall frequency (82.2%) observed for nsp12 P323L that consistently increased over time. Low sequence variation in the RNA replication complex was also observed among the mink isolates. Importantly, the coronavirus Nsp12 mutations previously selected in vitro in the presence of RDV were identified in only 2 isolates (0.002%) within all the analyzed sequences. In addition, among the sequence variants observed in [≥]0.5% clinical isolates, including P323L, none were located near the established polymerase active site or sites critical for the RDV mechanism of inhibition. In summary, the low diversity and high genetic stability of the RNA replication complex observed over time and in the recently emerged SARS-CoV-2 variants suggests a minimal global risk of pre-existing SARS-CoV-2 resistance to RDV.

Current research on liver regeneration: Pathogenesis and serum markers / 临床肝胆病杂志

Liver regeneration is an important response after liver injury and necrosis to maintain liver volume and function, with the involvement of various factors and signaling pathways. This process has three main stages, i.e., the initial stage of mitosis triggered by certain factors, the proliferation stage of promoting hepatocytes to enter the cell cycle, and the termination stage of promoting liver cells to reach a certain number and the recovery of liver mass. This article introduces various factors and multiple cellular signaling pathways that promote the differentiation of liver stem cells into liver cells to restore liver volume and function and summarizes the previous research findings of our group that alpha-fetoprotein is an important serum marker for liver regeneration after liver failure. The analysis shows that in-depth studies of the occurrence and clinical application of liver regeneration will help to improve the understanding of liver regeneration, better predict the prognosis of acute and chronic liver diseases, and provide new ideas and methods for the clinical diagnosis and treatment of various advanced liver diseases.

Repair of pulmonary atresia with ventricular septal defect: choice of right ventricle outflow tract reconstruction / 中华胸心血管外科杂志

Objective To compare the two different ways of right ventricular outflow tract(RVOT) reconstruction at repair of pulmonary atresia with ventricular septal defect,the direct RV-PA anastomosis and pericardial conduit to find the better way.Methods From Jun.2002 to Oct.2012,66 patients underwent pulmonary atresia with ventricular septal defect repair in our hospital,age at operation from 14 days to 272 months.Patients were divided into 2 groups according to the way of RVOT reconstruction.Group 1:31 of them,using direct RV-PA anastomasis,Group 2:35 of them,using pericardial conduit.Paired t test was used to evaluate the growth of pulmonary arteries.Chi-square test and Kaplan-Meier were used to calculate the postoperative mortality,reopemtion situation and survival time.Results There are 3 early hospital death in group 1 (9.7 ％),and 5 in group 2(14.3％),P =0.71.There is a significant difference between the two groups in restenosis rate of the RV-PA anastomasis and autologous pericardial conduit with pulmonary branch artery(Group 1:22.2％,Group 2:55.6％,P =0.01).The diameters of RV-PA anastomasis and the pulmonary artery branches in follow-up were significantly lager than the earlier diameters(P ＜ 0.05) in group 1.There is no growth on diameters of the pericardial conduit and pulmonary branches except the right pulmonary artery in follow-up in group 2.There is no significant difference between the two groups in later survival(P =0.30).Conclusion Both the direct anastomasis of RV-PA and pericardial conduit are available for RVOT reconstruction in pulmonary atresia with ventricular setal defect repair.There is lower incidence of RVOT and pulmonary stenosis and anastomosis absolutely has the ability for later growth in the former.

Evaluating right heart function after right ventricle-pulmonary anastomosis for right ventricle outflow reconstruction / 中华胸心血管外科杂志

Objective To evaluate the right heart function with echocardiography after right ventricle-pulmonary artery (RV-PA) anastomasis for right ventricle outflow (RVOT) reconstruction in patients with different types of pulmonary atresia and ventricle septal defect(PA/VSD).Methods From Nov 2002 to Aug 2013,31 patients with PA/VSD had undergone right ventricle-pulmonary anastomasis to reconstruct RVOT for radical or palliative repair.Related echocardiography indexs including strain/rate etc.were used to evaluate the right heart function and the progress of the right heart valves regurgitation.Results There were 3 early hospital deaths.No later death during follow-up.The echocardiography suggested the pulmonary artery and tricuspid regurgitation were more serious,however,the right heart function was relatively fine.The regurgitation of tricuspid valve was positive correlation with duration of follow-up (P =0.016).Conclusion The right heart function in follow-up keeps relatively well,and tricuspid valve regurgitation needs a long-term follow-up.

A feasibility study of coelocentesis in prenatal diagnosis / 中国医师杂志

Objective To explore the feasibility of coelocentesis in prenatal diagnosis.Methods Coelocentesis were applied on 58 women scheduled for at 6～12 weeks of gestation,and fetal heart rate before the procedure and 1,5,30 minutes afterwards and hemorrhage of amnionic cyst was observed.Y gene of sex-determining region was detected by polymerase chain reaction,and compared with chorionic villi sample.Results The total achievement ratio of coelocentesis was 96.6% of all cases in five minutes.The coelomic fluid was successfully aspirated at first attempt in 93.2% at 7～10 week's gestation,25.0% at 6～7weeks and 50.0% at 10 ~ 12 weeks.There was no significant difference in FHR between before coelocentesis and afterwards (P＞0.05).The detection accurate rate of SRY was 91.1%,all female fetus were matched with those observation by chorionic villi sampling,and only 5 male fetus were not matched,the accurate rate was 80.8%.Conclusion Coclocentesis has the advantage of simple procedure,safe and high feasibility.The optimal time of coclocentesis is in the 7th to 10th week of gestation.

Detection of alpha-thalassemia gene by coelocentesis in early prenatal diagnosis / 中华围产医学杂志

Objective To investigate the safety and accuracy of diagnosing alpha-thalassemia with extraembryonic coelomic cells. Methods Coelocentesis was performed before artificial abortion to collect extraembryonic coelmic fluid in 40 women with singleton pregnancy during 6-10 gestational weeks. The villi was gathered after suction. PCR technique was used to amplify alpha-thalassemia gene in both extraembryonic coelomic cells and villi and concordant rate of two different kinds of samples were compared. Results The genotypes of alpha-thalassemia were successfully amplified in 37 cases of coelomic cells and all were concordant with the results of villi. Conclusion Extraembryonic coelomic cells can be used in early prenatal diagnosis of alpha-thalassemia by PCR technique and is practicable.