Bioinformatics-based design of novel antigenic B-cell linear epitopes of Deinagkistrodon acutus venom

OBJECTIVE

With the help of bioinformatics analysis, we wished to develop a novel antivenom against the Deinagkistrodon (D.) acutus snake venom using B-cell linear epitopes of three primary toxins (serine protease, metalloprotease, and phospholipase A2).

MATERIALS AND METHODS

cDNA sequences of three toxins of D. acutus venom were retrieved from the NCBI database. B-cell linear epitopes were predicted using DNAStar and the website server software provided by IEDB. Then, the sequences of the predicted epitopes were artificially synthesized and inserted into the vector pET-32a-c(+). Recombinant antigen peptide was expressed and purified. BALB/c mice were immunized with the recombinant antigen peptide. The immunoprotective effect of this novel antivenom was measured by neutralization of venom haemorrhagic activity.

RESULTS

Six epitopes were obtained by bioinformatics analysis. ELISA analysis showed that antibody titre was >8,000 against snake venom and >64,000 against the recombinant peptide. Neutralization assays confirmed that the developed antivenom could effectively reduce the haemorrhagic activity of snake venom.

CONCLUSIONS

Six B-cell linear epitopes of D. acutus snake venom were predicted by bioinformatics analysis and successfully utilized to produce a novel antivenom.

Potential role of heat-shock proteins in giant cell tumors

We investigated the differential expression protein profile of giant cell tumors (GCTs), which can be used to monitor the tumor's recurrence and metastasis, to provide preliminary results for further study. We also explored heat-shock protein (HSP) inhibitor that prevents tumors from recurring and migrating. A stable isotope-labeling strategy using isobaric tags for relative and absolute quantitation coupled with two-dimensional liquid chromatography tandem mass spectrometry was used to separate and identify differentially expressed proteins. A total of 467 differentially expressed proteins were identified in GCT tissues. Up to 311 proteins were upregulated, whereas 156 proteins were downregulated in GCT tissues. Three of the differentially expressed HSPs, namely HP90A, HSPB1, and HSPB2, were upregulated. The differentially expressed proteins of GCT tissues will provide a scientific foundation for tumor prognosis, and for further studies exploring HSP inhibitor to prevent tumor recurrence and migration.

Juvenile ossifying fibroma of the jaw: a retrospective study of 15 cases

The management of patients with juvenile ossifying fibroma (JOF) remains controversial. To explore the correlations between different treatments and the patient prognosis, 15 cases of JOF of the jaw were reviewed. Five patients were male and 10 were female. Patient age at the time of disease onset ranged from 7 to 18 years (mean 10.9 years). Nine tumours were located in mandible and six in the maxilla. These cases typically manifested clinically as painless swelling of the jaw (9/15, 60%); 40% (6/15) of the cases were associated with pain, diplopia, stuffy nose, and/or rapid growth. Images of JOF can show a radiolucent, mixed, or ground glass-like appearance. Pathological examinations revealed 10 cases of juvenile trabecular ossifying fibroma (JTOF) and five cases of juvenile psammomatoid ossifying fibroma (JPOF). In terms of the treatment plan, six patients initially received radical surgery; nine patients underwent conservative treatment, among whom six (6/9, 66.7%) had one or more recurrence. At the end of the follow-up period, 12 patients had no evidence of tumour recurrence and three cases were alive with a tumour. In summary, surgeons should develop the surgical plan according to the extent of the lesion, relapse status, growth rate, and family choice, and these patients should be followed up closely.

MicroRNA-215 functions as a tumor suppressor and directly targets ZEB2 in human pancreatic cancer

It has been shown that microRNA-215 (miR-215) is dysregulated in several human malignancies, and this correlates with tumor progression. However, its expression and function in pancreatic cancer is still unclear. The aim of this study was to explore the effects of miR-215 on pancreatic cancer formation and progression. Using quantitative RT-PCR, we detected miR-215 expression in pancreatic cancer cell lines and primary tumor tissues. The association of miR-215 expression with clinicopathological factors and prognosis was also analyzed. We then observed the effects of miR-215 on the biological behavior of pancreatic cancer cells. Lastly, the potential regulatory function of miR-215 on ZEB2 expression was investigated. miR-215 expression levels were significantly downregulated in pancreatic cancer samples and cell lines. Decreased miR-215 expression was significantly associated with large tumor size, advanced TNM stage, lymph node metastasis, vessel invasion, and lower overall survival. Multivariate regression analysis corroborated that downregulation of miR-215 was an independent unfavorable prognostic factor. Overexpression of miR-215 inhibited pancreatic cancer cell proliferation, invasion, and migration; promoted cell apoptosis in vitro; and suppressed tumorigenicity in vivo. Further, ZEB2 was confirmed as a direct target of miR-215 by using a luciferase reporter assay. These findings indicate that miR-215 may act as a tumor suppressor in pancreatic cancer cells, and could serve as a novel therapeutic target for miR-based therapy.

Fusion of Magnetic Resonance Imaging and Real-Time Elastography to Visualize Prostate Cancer: A Prospective Analysis using Whole Mount Sections after Radical Prostatectomy

PURPOSE

To determine whether the fusion of multiparametric magnetic resonance imaging (MRI) with transrectal real-time elastography (RTE) improves the visualization of PCa lesions compared to MRI alone.

MATERIALS AND METHODS

In a prospective setting, 45 patients with biopsy-proven PCa received prostate MRI prior to radical prostatectomy (RP). T2 and diffusion-weighted imaging (T2WI/DW-MRI) and, if applicable, dynamic contrast-enhanced sequences (T2WI/DW/DCE-MRI) were used to perform MRI/RTE fusion. The probability of PCa on MRI was graded according to the PI-RADS score for 12 different prostate sectors per patient. MRI images were fused with RTE to stratify suspicious from non-suspicious sectors. Imaging results were compared to whole mount sections using nonparametrical receiver operating characteristic curves and the area under these curves (AUC).

RESULTS

41 of 45 patients were eligible for final analyses. Histopathology confirmed PCa in 261 (53%) of 492 prostate sectors. MRI alone provided an AUC of 0.62 (T2WI/DW-MRI) and 0.65 (T2WI/DW/DCE-MRI) to predict PCa and was meaningfully enhanced to 0.75 (T2WI/DW-MRI) and 0.74 (T2WI/DW/DCE-MRI) using MRI/RTE fusion. Sole MRI showed a sensitivity and specificity of 57.9% and 61% with the best results for ventral prostate sectors whereas RTE was superior in dorsal and apical sectors. MRI/RTE fusion improved sensitivity and specificity to 65.9% and 75.3%, respectively. Additional use of DCE sequences showed a sensitivity and specificity of 65% and 55.7% for MRI and 72.1% and 66% for MRI/RTE fusion.

CONCLUSION

MRI/RTE fusion provides improved PCa visualization by combining the strength of both imaging techniques in regard to prostate zonal anatomy and thereby might improve future biopsy-guided PCa detection.

Impact of pH on molecular structure and surface properties of lentil legumin-like protein and its application as foam stabilizer

The capacity of a protein to form and stabilize foams and emulsions depends on its structural characteristics and its physicochemical properties. The structural properties of lentil legumin-like protein including molecular weight, hydrodynamic size, surface charge and hydrophobicity, and conformation were studied in relation to its air-water interfacial behaviors. Kinetics study suggested that the foaming stability was closely related to the surface conformation of the protein that strongly affected adsorption and re-organization of the protein layer at the air-water interface. Foams prepared at neutral pH showed dense and strong networks at the interface, where combination of the α-helix secondary structure, medium hydrodynamic molecular size, and balance between solubility/hydrophobicity all contributed to the formation of such strong protein network at the interface. At pH 5.0, the protein formed a dense and thick network composed of randomly aggregated protein particles at the air-water interface. Whereas at pH 3.0, the unordered structure increased intra-protein flexibility producing a less compact and relaxed interface that reduces elasticity modulus with time and reduced foam resistance against collapse. This research revealed that lentil legumin-like protein could form long-life foams at mild acidic and neutral pH. The potential for use of lentil protein as a novel foaming plant-based stabilizer is demonstrated in food and non-food applications where stable, long-life foams are required.

Maternal hyperoxygenation improves left heart filling in fetuses with atrial septal aneurysm causing impediment to left ventricular inflow

OBJECTIVES

Aneurysm of the atrial septum (AAS) with excessive excursion of septum primum into the left atrium is an uncommon and relatively benign fetal condition associated with impediment to left ventricular (LV) filling and the appearance of a slender, but apex-forming, LV on fetal echocardiography. Impediment to filling can be severe, creating the image of LV hypoplasia with retrograde aortic flow. We hypothesize that maternal hyperoxygenation alters atrial septal position, improves LV filling, and normalizes aortic flow in fetuses with AAS by increasing fetal pulmonary venous return.

METHODS

Fetal echocardiography was performed prior to, and at 10 min of, maternal hyperoxygenation in 12 fetuses with AAS who were referred to our center because of LV hypoplasia. Atrial septal excursion (ASE), LV and right ventricular (RV) sphericity index (SI) and direction of flow in the aortic isthmus, as determined by Doppler, were measured.

RESULTS

With maternal hyperoxygenation, mean ± SD ASE decreased (0.76 ± 0.17 before maternal hyperoxygenation vs 0.53 ± 0.23 after maternal hyperoxygenation; P < 0.01), consistent with increased pulmonary venous return, LV-SI increased (0.29 ± 0.06 vs 0.42 ± 0.06; P < 0.001), indicating increased LV filling, and the direction of aortic isthmus flow changed from retrograde in all cases prior to maternal hyperoxygenation to antegrade in 10 and to bidirectional in two. RV-SI remained unchanged (0.53 ± 0.13 vs 0.52 ± 0.10; P = 0.7).

CONCLUSIONS

In cases of AAS, short-term maternal hyperoxygenation increases fetal pulmonary venous return, substantially alters LV geometry and promotes antegrade flow in the aortic isthmus. This demonstrates proof-of-concept that maternal hyperoxygenation can improve filling of the left side of the fetal heart in AAS.

Non-invasive prenatal testing for trisomies 21, 18 and 13: clinical experience from 146,958 pregnancies

OBJECTIVES

To report the clinical performance of massively parallel sequencing-based non-invasive prenatal testing (NIPT) in detecting trisomies 21, 18 and 13 in over 140,000 clinical samples and to compare its performance in low-risk and high-risk pregnancies.

METHODS

Between 1 January 2012 and 31 August 2013, 147,314 NIPT requests to screen for fetal trisomies 21, 18 and 13 using low-coverage whole-genome sequencing of plasma cell-free DNA were received. The results were validated by karyotyping or follow-up of clinical outcomes.

RESULTS

NIPT was performed and results obtained in 146,958 samples, for which outcome data were available in 112,669 (76.7%). Repeat blood sampling was required in 3213 cases and 145 had test failure. Aneuploidy was confirmed in 720/781 cases positive for trisomy 21, 167/218 cases positive for trisomy 18 and 22/67 cases positive for trisomy 13 on NIPT. Nine false negatives were identified, including six cases of trisomy 21 and three of trisomy 18. The overall sensitivity of NIPT was 99.17%, 98.24% and 100% for trisomies 21, 18 and 13, respectively, and specificity was 99.95%, 99.95% and 99.96% for trisomies 21, 18 and 13, respectively. There was no significant difference in test performance between the 72,382 high-risk and 40,287 low-risk subjects (sensitivity, 99.21% vs. 98.97% (P = 0.82); specificity, 99.95% vs. 99.95% (P = 0.98)). The major factors contributing to false-positive and false-negative NIPT results were maternal copy number variant and fetal/placental mosaicism, but fetal fraction had no effect.

CONCLUSIONS

Using a stringent protocol, the good performance of NIPT shown by early validation studies can be maintained in large clinical samples. This technique can provide equally high sensitivity and specificity in screening for trisomy 21 in a low-risk, as compared to high-risk, population.

Frequent proviral integration of the human betaretrovirus in biliary epithelium of patients with autoimmune and idiopathic liver disease

BACKGROUND

A human betaretrovirus (HBRV) has been linked with primary biliary cirrhosis (PBC) following the detection of viral particles in biliary epithelium by electron microscopy and cloning of the betaretrovirus genome from biliary epithelium and peri-hepatic lymph nodes. Evidence for viral infection was found in the majority of PBC patients' peri-hepatic lymph node samples. However, less than a third of the liver samples had detectable HBRV, whereas others were unable to detect betaretrovirus infection or noted the presence of virus in the liver of patients with other diagnoses.

AIMS

To address the hypothesis that the betaretrovirus may be below the limits of detection in the liver, biliary epithelial cells (BEC) were investigated for the evidence of infection.

METHODS

Ligation-mediated PCR and next generation sequencing were used to detect proviral integrations in liver, lymph nodes and BEC isolated from liver transplant recipients. Hybridisation-based assays were used to detect betaretroviral RNA in BEC.

RESULTS

Unique HBRV integrations and betaretrovirus RNA were detected in the majority of biliary epithelia derived from patients with PBC, autoimmune hepatitis and cryptogenic liver disease but rarely in other liver transplant recipients with primary sclerosing cholangitis and other hepatic disorders. HBRV integrations were commonly found in PBC patients' lymph nodes but rarely in whole liver samples.

CONCLUSIONS

Human betaretrovirus infection is frequently observed at the site of disease in patients with primary biliary cirrhosis and also in biliary epithelium of patients with autoimmune hepatitis and cryptogenic liver disease.