Influencing factors for chronic pancreatitis complicated by pancreatogenic portal hypertension and establishment of a predictive model / 临床肝胆病杂志

ObjectiveTo investigate the influencing factors for chronic pancreatitis （CP） complicated by pancreatogenic portal hypertension （PPH）， and to establish a predictive model. MethodsA retrospective analysis was performed for the clinical data of 99 patients with CP complicated by PPH who were hospitalized in The First Affiliated Hospital of Kunming Medical University， Chuxiong Yi Autonomous Prefecture People’s Hospital， Wenshan People’s Hospital， and Puer People’s Hospital from January 2017 to December 2022， and these patients were enrolled as PPH group. The incidence density sampling method was used to select 198 CP patients from databases as control group. The independent-samples t test was used for comparison of normally distributed continuous data between two groups， and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups； the chi-square test or the Fisher’s exact test was used for comparison of categorical data between two groups. The Least Absolute Shrinkage and Selection Operator （LASSO） regression model was used to identify the potential predictive factors for CP complicated by PPH， and the predictive factors obtained were included in the multivariate Logistic regression analysis to obtain independent risk factors， which were used to establish a nomogram prediction model. The receiver operating characteristic （ROC） curve， the calibration curve， and the Hosmer-Lemeshow goodness-of-fit test were used to perform internal validation of the model， and the clinical decision curve was used to assess the clinical practicability of the model. ResultsThere were significant differences between the two groups in sex， history of recurrent acute pancreatitis attacks， acute exacerbation of CP， bile duct stones， peripancreatic fluid accumulation， pseudocysts， pulmonary infection， elevated C-reactive protein （CRP）， elevated procalcitonin， fibrinogen （FIB）， neutrophil-lymphocyte ratio （NLR）， gamma-glutamyl transpeptidase， total bilirubin， direct bilirubin， low-density lipoprotein （LDL）， serum amylase， D-dimer， and serum albumin （all P<0.05）. The predictive variables obtained by the LASSO regression analysis included sex， recurrent acute pancreatitis attacks， bile duct stones， peripancreatic fluid accumulation， pulmonary infection， pseudocysts， CRP， NLR， FIB， and LDL. The multivariate Logistic regression analysis showed that sex （odds ratio ［OR］=2.716， P<0.05）， recurrent acute pancreatitis attacks （OR=2.138， P<0.05）， peripancreatic fluid accumulation （OR=2.297， P<0.05）， pseudocysts （OR=2.805， P<0.05）， and FIB （OR=1.313， P<0.05） were independent risk factors for CP complicated by PPH. The above factors were fitted into the model， and the Bootstrap internal validation showed that the nomogram model had an area under the ROC curve of 0.787 （95% confidence interval： 0.730 — 0.844）， and the calibration curve was close to the reference curve. The Hosmer-Lemeshow goodness-of-fit test showed that the model had a good degree of fitting （χ2=7.469， P=0.487）. The clinical decision curve analysis showed that the prediction model had good clinical practicability. ConclusionMale sex， recurrent acute pancreatitis attacks， peripancreatic fluid accumulation， pseudocysts， and FIB are independent risk factors for CP complicated by PPH， and the nomogram model established has good discriminatory ability， calibration， and clinical practicability.

Function and Cryo-EM structures of broadly potent bispecific antibodies against multiple SARS-CoV-2 Omicron sublineages

The SARS-CoV-2 variant, Omicron (B.1.1.529), rapidly swept the world since its emergence. Compared with previous variants, Omicron has a high number of mutations, especially those in its spike glycoprotein that drastically dampen or abolish the efficacy of currently available vaccines and therapeutic antibodies. Several major sublineages of Omicron involved, including BA.1, BA.2, BA.2.12.1, BA.3 and BA.4/BA.5, rapidly changing the global and regional landscape of the pandemic. Although vaccines are available, therapeutic antibodies remain critical for infected and especially hospitalized patients. To address this, we have designed and generated a panel of human/humanized therapeutic bispecific antibodies against Omicron and its sub-lineage variants, with activity spectrum against other lineages. Among these, the top clone CoV2-0213 has broadly potent activities against multiple SARS-CoV-2 ancestral and Omicron lineages, including BA.1, BA.1.1, BA.2, BA.2.12.1, BA.3 and BA.4/BA.5. We have solved the cryo-EM structure of the lead bi-specific antibody CoV-0213 and its major Fab arm MB.02. Three-dimensional structural analysis shows distinct epitope of antibody - spike receptor binding domain (RBD) interactions, and demonstrates that both Fab fragments of the same molecule of CoV2-0213 can target the same spike trimer simultaneously, further corroborating its mechanism of action. CoV2-0213 represents a unique and potent broad-spectrum SARS-CoV-2 neutralizing bispecific antibody (nbsAb) against the currently circulating major Omicron variants (BA.1, BA.1.1, BA.2, BA.2.12.1, BA.3 and BA.4/BA.5), while maintaining activity against certain ancestral lineages (WT/WA-1, Delta), and to some degree other {beta}-coronavirus species (SARS-CoV). CoV2-0213 is primarily human and ready for translational testing as a countermeasure against the ever-evolving pathogen.

Monospecific and bispecific monoclonal SARS-CoV-2 neutralizing antibodies that maintain potency against B.1.617

COVID-19 pathogen SARS-CoV-2 has infected hundreds of millions and caused over 5 million deaths to date. Although multiple vaccines are available, breakthrough infections occur especially by emerging variants. Effective therapeutic options such as monoclonal antibodies (mAbs) are still critical. Here, we report the development, cryo-EM structures, and functional analyses of mAbs that potently neutralize SARS-CoV-2 variants of concern. By high-throughput single cell sequencing of B cells from spike receptor binding domain (RBD) immunized animals, we identified two highly potent SARS-CoV-2 neutralizing mAb clones that have single-digit nanomolar affinity and low-picomolar avidity, and generated a bispecific antibody. Lead antibodies showed strong inhibitory activity against historical SARS-CoV-2 and several emerging variants of concern. We solved several cryo-EM structures at [~]3 [A] resolution of these neutralizing antibodies in complex with prefusion spike trimer ectodomain, and revealed distinct epitopes, binding patterns, and conformations. The lead clones also showed potent efficacy in vivo against authentic SARS-CoV-2 in both prophylactic and therapeutic settings. We also generated and characterized a humanized antibody to facilitate translation and drug development. The humanized clone also has strong potency against both the original virus and the B.1.617.2 Delta variant. These mAbs expand the repertoire of therapeutics against SARS-CoV-2 and emerging variants.

Nonstructural protein 1 of SARS-CoV-2 is a potent pathogenicity factor redirecting host protein synthesis machinery toward viral RNA.

The COVID-19 pandemic affects millions of people worldwide with a rising death toll. The causative agent, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), uses its nonstructural protein 1 (Nsp1) to redirect host translation machinery to the viral RNA by binding to the ribosome and suppressing cellular, but not viral, protein synthesis through yet unknown mechanisms. We show here that among all viral proteins, Nsp1 has the largest impact on host viability in the cells of human lung origin. Differential expression analysis of mRNA-seq data revealed that Nsp1 broadly alters the transcriptome in human cells. The changes include repression of major gene clusters in ribosomal RNA processing, translation, mitochondria function, cell cycle and antigen presentation; and induction of factors in transcriptional regulation. We further gained a mechanistic understanding of the Nsp1 function by determining the cryo-EM structure of the Nsp1-40S ribosomal subunit complex, which shows that Nsp1 inhibits translation by plugging the mRNA entry channel of the 40S. We also determined the cryo-EM structure of the 48S preinitiation complex (PIC) formed by Nsp1, 40S, and the cricket paralysis virus (CrPV) internal ribosome entry site (IRES) RNA, which shows that this 48S PIC is nonfunctional due to the incorrect position of the 3 region of the mRNA. Results presented here elucidate the mechanism of host translation inhibition by SARS-CoV-2, provide insight into viral protein synthesis, and furnish a comprehensive understanding of the impacts from one of the most potent pathogenicity factors of SARS-CoV-2. HighlightsORF screen identified Nsp1 as a major cellular pathogenicity factor of SARS-CoV-2 Nsp1 broadly alters the gene expression programs in human cells Nsp1 inhibits translation by blocking mRNA entry channel Nsp1 prevents physiological conformation of the 48S PIC

Early diagnostic value of plasma miR-155, miR-196a, miR-21 and miR-210 in patients with pancreatic cancer / 肿瘤

Objective: To evaluate the clinical value of the plasma microRNA-155 (miR-155), miR-196a, miR-21 and miR-210 in early diagnosis of patients with pancreatic cancer. Methods: The real-time fluorescent quantitative-PCR was performed to detect the levels of miR-155, miR-196a, miR-21 and miR-210 in plasma samples from sixty patients with pancreatic cancer, twenty patients with chronic pancreatitis, and ten healthy volunteers, as well as the levels of four miRNAs in cancer tissue specimens from ten patients with pancreatic cancer. The serum tumor markers carbohydrate antigen 199 (CA199), CA242 and carcino-embryonic antigen (CEA) were simultaneously detected. The relative expression levels of four miRNAs in plasma among these three groups were compared, and the relationship between miRNA levels in plasma and their levels in pancreatic cancer tissues were statistically analyzed. Finally, the diagnostic efficiency of plasma miR-155, miR-196a, miR-21 and miR-210 for pancreatic cancer was evaluated. Results: The relative expression levels of plasma miR-155, miR-196a, miR-21 and miR-210 in pancreatic cancer group were significantly higher than those in the chronic pancreatitis group and the healthy control group (all P 0.05). The area under receiver operating characteristic (AUC-ROC) curve of plasma miR-155, miR-196a, miR-21 and miR-210 in diagnosis of pancreatic cancer indicated that these four miRNAs had diagnostic value independently (all P < 0.01), in which miR-155 had the highest diagnostic efficiency. The binary Logistic regression model showed that combined detection of plasma miR-196a and miR-210 was more effective in diagnosis of stageI pancreatic cancer as compared with CA199. Conclusion: The plasma miR-155, miR-196a, miR-21 and miR-210 levels are effective to distinguish pancreatic cancer from non-pancreatic cancer. The combined detection of miR-196a and miR-210 may become a promising method for early diagnosis of pancreatic cancer.

Research progress of the relationship between miRNAs and pancreatic carcinoma / 医学研究生学报

MiRNA is a small non-coding single stranded RNA(ssRNA)which is made up by 21~23 nucleotide.This ssRNA has a double effect as tumor suppressor genes and oncogenes , and plays an important role in cell proliferation , differentiation and apop-tosis.Pancreatic carcinoma is a highly malignant tumor with poor prognosis and high mortality rate , and the early diagnosis is difficult . In the last decades , growing studies highlighted the interactions between miRNAs and pancreatic carcinoma .This review provides a re-search overview between miRNAs and pancreatic carcinoma .Meanwhile , the significance of Expression Profile in pancreatic carcinoma′s diagnosis ,treatment and prognosis is also discussed .