[The consideration about study design and implementation of vaccine clinic trials]

The safety of prophylactic vaccine is one of the key points both in clinical trials and evaluation. Based on the review practice of vaccine registration clinical trials in recent years, we puts forward a series of thoughts and suggestions on the common problems of safety study on vaccine, including the hypothesis of safety study, the consideration of inclusion/exclusion criteria and suspension/termination criteria for study; the routine requirements of safety study and some special issue such as medical laboratory test index, vaccine virus shedding and safety of adjuvant, and further clarifies the requirements of safety observation on sequential enrollment; also emphasized the scientific judgment of causality and the quality of safety monitoring. It can be used for reference by vaccine researchers and to explore appropriate solutions to promote vaccine research & development and risk control in China.

[The consideration about safety data analysis and expression in instructions of vaccine clinic trials]

The safety of prophylactic vaccine is one of the key points both in clinical trials and evaluation. Based on the review practice of vaccine registration clinical trials in recent years, we summarized the common problems in safety analysis and report and accordingly puts forward a series of thoughts and suggestions, including discussing the role of statistics in safety analysis, putting forward the framework of safety analysis and report involved analysis content, analysis index and analysis dimension, in which attention is paid to the severity analysis; emphasizing the initiative analysis on risk signal and encouraging the evidence-based initiative safety evaluation. At the same time, this paper discusses the basic principles of the presentation of safety data in the package inserts, as well as the comprehensive consideration of the safety data of each phase of the trial and different subjects. It can be used for reference by sponsor to promote vaccine clinical research and evaluation in China.

A high throughput method for quantifying number and size distribution of Arabidopsis seeds using large particle flow cytometry

BACKGROUND

Seed size and number are important plant traits from an ecological and horticultural/agronomic perspective. However, in small-seeded species such as Arabidopsis thaliana, research on seed size and number is limited by the absence of suitable high throughput phenotyping methods.

RESULTS

We report on the development of a high throughput method for counting seeds and measuring individual seed sizes. The method uses a large-particle flow cytometer to count individual seeds and sort them according to size, allowing an average of 12,000 seeds/hour to be processed. To achieve this high throughput, post harvested seeds are first separated from remaining plant material (dust and chaff) using a rapid sedimentation-based method. Then, classification algorithms are used to refine the separation process in silico. Accurate identification of all seeds in the samples was achieved, with relative errors below 2%.

CONCLUSION

The tests performed reveal that there is no single classification algorithm that performs best for all samples, so the recommended strategy is to train and use multiple algorithms and use the median predictions of seed size and number across all algorithms. To facilitate the use of this method, an R package (SeedSorter) that implements the methodology has been developed and made freely available. The method was validated with seed samples from several natural accessions of Arabidopsis thaliana, but our analysis pipeline is applicable to any species with seed sizes smaller than 1.5 mm.

Comparison of Hogan pharyngeal flap and sphincter pharyngoplasty in postoperative velopharyngeal function

The purpose of this study was to compare speech and breathing after sphincter pharyngoplasty and the Hogan pharyngeal flap in the management of cleft-related velopharyngeal insufficiency (VPI). We reviewed 78 patients with VPI who had either the Hogan flap (n=30) or sphincter pharyngoplasty (n=48) between 2009 and 2011. Velopharyngeal function, nasal patency, and speech were compared. In the Hogan flap group, 25 patients had achieved velopharyngeal competence and nine had normal speech. In the sphincter pharyngoplasty group, 29 patients achieved velopharyngeal competence and 20 normal speech. The Hogan flap group had a higher rate of velopharyngeal competence (n=25) than the sphincter pharyngoplasty group (p=0.033), but there was no significant difference in intelligibility of speech. Eighteen patients in the Hogan flap group and 33 in the sphincter pharyngoplasty group reported symptoms of snoring, with no significant difference in nasal ventilation. Our results suggest that a posterior pharyngeal flap is a more effective technique for managing VPI after repair of cleft palate than sphincter pharyngoplasty, and causes no more postoperative complications in nasal breathing.

Preventive effects of low molecular weight heparin on formation of deep vein thrombosis by reducing D dimer values in patients undergoing spinal surgery

OBJECTIVE

Deep vein thrombosis (DVT) is one of the most common complications for patients undergoing spinal surgery. This study aims to investigate preventive effects of low-molecular-weight heparin (LMWH) on the formation of DVT.

PATIENTS AND METHODS

This study involved 37 patients who underwent spinal surgery between April 2016 and April 2017. Patients were divided into LMWH group and Control group. Clinical parameters, including operation time, intra-operative blood loss, incision length, post-operative visual analogue scale (VAS), exercise-time leaving bed and post-operative extubation time, were collected. Blood routine analysis, including platelet count (PLT), red blood cell count (RBC), white blood cell count (WBC) and hemoglobin (HGB) were also conducted. Coagulation parameters, including prothrombin time-international normalized ratio (PT-INR), fibrinogen (FIB), activated partial thromboplastin time (APTT), thrombin time (TT), prothrombin time 1 (PT-1) and D-dimer (DD), were evaluated. The drainage fluid was collected.

RESULTS

LMWH treatment significantly decreased operative time, blood loss and incision length compared to Control group at 1st, 3rd and 7th day post-operation (all p<0.05). LMWH treatment significantly increased WBC levels compared to Control group at 1st, 3rd and 7th day post-operation (p<0.05). LMWH treatment significantly decreased DD levels in the post-operative patients compared to Control group at 1st, 3rd and 7th day post-operation (p<0.05). However, LMWH treatment doesn't affect drainage amounts of patients. DD levels were positively correlated with WBC counts for the LMWH treated patients.

CONCLUSIONS

Low molecular weight heparin effectively prevents the formation of DVT by reducing DD values in patients undergoing spinal surgery.

444Plasma levels of microfibrillar associated protein type 4 (MFAP4) are predictive for aortic dissection in patients with Marfan Syndrome

Aim

Marfan syndrome is a disorder with mutations in the fibrillin-1 gene, leading to elastic fiber degradation and increased TGF-beta signaling. The life-threatening feature of Marfan is aneurysm formation with a risk of fatal aortic dissections. In a proteomics screen, we identified MFAP4, a protein involved in fibrillin-1 and elastic fiber formation, to be increased in the Marfan aorta. We aim to study the role of MFAP4 in Marfan aortic disease.

Methods and results

MFAP4 co-localizes in the aorta with elastin and collagen fibers.

In vitro experiments show that MFAP4 expression is upregulated by TGF-beta, which could explain the increased MFAP4 protein levels in the Marfan aorta.

In a substudy of 96 Marfan patients from the COMPARE trial, MFAP4 levels correlate with aortic root diameter (r=0.30, p=0.01). Patients previously enrolled in the COMPARE trial were retrospectively analyzed. Cardiovascular events, including aortic dissection, were assessed. Plasma samples were prospectively collected at time of inclusion in the study and analyzed retrospectively on MFAP4. In the 7 years of follow up, 5 Type B dissections occurred, all of them in patients in the upper tertile of plasma MFAP4. High plasma MFAP4 associates with poor dissection-free survival (Figure 1).

Moreover, the aortic distensibility as measure for aortic stiffness and damage, was calculated throughout the aorta from available MRI images of these patients. Interestingly, in the descending thoracic aorta where type B dissections occur, the aortic distensibility is significantly lower (indicating decreased aortic elasticity) in Marfan patients with high plasma MFAP4, thus associating with aortic damage.

Figure 1

Conclusion

MFAP4, a protein involved in extracellular matrix assembly, is elevated in the Marfan aorta. High plasma MFAP4 seems to reflect aortic damage and predicted type B aortic dissections in up to 7 years follow up.

VEGFR2 and VEGF-C Suppresses the Epithelial-Mesenchymal Transition Via YAP in Retinal Pigment Epithelial Cells

BACKGROUND

Whereas retinal pigment epithelial (RPE) cells are known to secrete VEGF-A and VEGFR2, the functions of the autocrine VEGF signaling remain unclear. Meanwhile, anti-VEGF therapies have been applied routinely to treat ocular vascular diseases.

OBJECTIVE

The aim of this study was to determine the functions of the VEGF signaling in RPE cells and evaluate the consequences of its interruption.

METHODS

The genes involved in the VEGF and Hippo signal pathways were knocked down with siRNAs in both ARPE-19 cell line and human primary RPE cells via transient transfection whereas overexpression of VEGFR2 was mediated via adenovirus transduction. Expression of the epithelial-mesenchymal transition (EMT) markers and the downstream genes of YAP were determined by real-time PCR and Western Blot analysis. Immunofluorescence staining was utilized to determine gene expression in tissue and mouse samples.

RESULTS

Knockdown of VEGFR2 results in epithelial-mesenchymal transition in vitro and in vivo. Overexpression of VEGFR2 suppresses TGF β-mediated EMT in RPE cells. Loss of VEGF-C rather than VEGF-A induces EMT. Mechanistically, the VEGFR2 ablation-induced EMT in RPE cells is mediated by activation of YAP, an effector of the Hippo pathway. Finally, the immunohistochemical analysis of VEGFR2 and YAP in human proliferative vitreoretinopathy (PVR) membranes indicates a tendency of an inverse correlation between VEGFR2-positive and YAP-positive cells.

CONCLUSIONS

Our results disclose unexpected novel roles of VEGFR2 and VEGF-C in the process of EMT of RPE cells and in the Hippo pathway. The data shown here demonstrated that VEGFR2 and VEGF-C are important to maintain the normal physiological state of RPE cells.

Spleen phenotype in autosomal dominant polycystic kidney disease

AIM

To evaluate splenic phenotype in autosomal dominant polycystic kidney disease (ADPKD) including presence of cysts and splenomegaly to determine if these are ADPKD related or represent unrelated incidental findings.

MATERIALS AND METHODS

The axial/coronal T2-weighted images of ADPKD patients (n=215) and age/gender-matched controls (n=215) were evaluated for the presence of T2-bright splenic lesions by three blinded observers. Spleen volume (SV) was evaluated in the context of clinical and imaging features as well as results of gene testing for PKD1 and PKD2 mutations.

RESULTS

T2-bright splenic lesions were found in 16 of 215 (7%) ADPKD patients compared to 11 of 215 (5%) control patients (p=0.32) and their prevalence was similar in patients with either PKD1 or PKD2 mutations. Median SV was significantly higher in ADPKD patients than controls (236 [182; 313 ml] versus 176 [129; 264 ml], p<0.0001). In multivariable analysis, height-adjusted SV (htSV) was not associated with the presence of liver cysts, haemorrhagic cysts, or infections; however, htSV was directly associated with height-adjusted total kidney volume (htTKV), a biomarker for ADPKD disease severity.

CONCLUSIONS

The prevalence of T2-bright splenic lesions is similar in ADPKD patients and non-ADPKD controls, suggesting no relation to the diagnosis of ADPKD; however, splenic enlargement in ADPKD compared to controls could not be explained by liver cystic involvement, by infection/inflammatory conditions, or by haemorrhagic renal cysts. This combined with direct correlation of htSV with htTKV, a biomarker of ADPKD severity, suggests splenomegaly may be related to the pathogenesis of ADPKD.

Long-term denosumab treatment restores cortical bone loss and reduces fracture risk at the forearm and humerus: analyses from the FREEDOM Extension cross-over group

Upper limb fractures (including wrist, forearm, and humerus) represent a significant burden among postmenopausal women with osteoporosis. Up to 7 years of treatment with denosumab resulted in an increase in bone mineral density and decrease in fractures in upper limb sites.

INTRODUCTION

Upper limb (wrist, forearm, and humerus) fractures are a significant burden in osteoporosis, associated with significant morbidity and mortality. Denosumab, a monoclonal antibody against RANK ligand, increases bone mineral density (BMD) and decreases vertebral, nonvertebral, and hip fractures. Here, we evaluated the long-term effect of denosumab treatment on upper limb fracture risk and BMD.

METHODS

In the FREEDOM trial, subjects were randomized 1:1 to receive every-6-month denosumab 60 mg or placebo subcutaneously for 3 years, after which all subjects could receive denosumab for up to 7 years (Extension). Among placebo subjects who completed FREEDOM and enrolled in the Extension, wrist, forearm, humerus, and upper limb fracture rates and rate ratios between different time periods (FREEDOM years 1-3, Extension years 1-3, and Extension years 4-7) were computed. BMD at the ultradistal radius, 1/3 radius, and total radius was analyzed in a subset of subjects in a BMD substudy.

RESULTS

This analysis included 2207 subjects (116 in the BMD substudy). Fracture rates decreased over the 7-year Extension; fracture rate ratios between Extension years 4-7 (denosumab) and FREEDOM years 1-3 (placebo) reduced significantly for the wrist (0.57), forearm (0.57), humerus (0.42), and upper limb (0.52; p < 0.05 for all). Percentage increase in BMD from Extension baseline at the ultradistal radius, 1/3 radius, and total radius was significant by Extension year 7 (p < 0.05 for all).

CONCLUSIONS

Long-term treatment with denosumab decreases upper limb fracture risk and increases forearm BMD, suggesting beneficial effects on both cortical and trabecular bone accruing over time.

Terebratulide brachiopod shell biomineralization by mantle epithelial cells

To understand mineral transport pathways for shell secretion and to assess differences in cellular activity during mineralization, we imaged with TEM and FE-SEM ultrastructural characteristics of outer mantle epithelium (OME) cells. Imaging was carried out on Magellania venosa shells embedded/etched, chemically fixed/decalcified and high-pressure frozen/freeze-substituted samples from the commissure, central shell portions and from puncta. Imaging results are complemented with morphometric evaluations of volume fractions of membrane-bound organelles. At the commissure the OME consists of several layers of cells. These cells form oblique extensions that, in cross-section, are round below the primary layer and flat underneath fibres. At the commissure the OME is multi-cell layered, in central shell regions it is single-cell layered. When actively secreting shell carbonate extrapallial space is lacking, because OME cells are in direct contact with the calcite of the forming fibres. Upon termination of secretion, OME cells attach via apical hemidesmosomes to extracellular matrix membranes that line the proximal surface of fibres. At the commissure volume fractions for vesicles, mitochondria and lysosomes are higher relative to single-cell layered regions, whereas for endoplasmic-reticulum and Golgi apparatus there is no difference. FE-SEM, TEM imaging reveals the lack of extrapallial space between OME cells and developing fibres. In addition, there is no indication for an amorphous precursor within fibres when these are in active secretion mode. Accordingly, our results do not support transport of minerals by vesicles from cells to sites of mineralization, rather by transfer of carbonate ions via transport mechanisms associated with OME cell membranes.

Pressure tuning of iron-based superconductor Ca10(Pt3As8) ((Fe0.95Pt0.05)2As2)5

Systematic high pressure transport measurements were performed on underdoped Ca₁₀(Pt₃As₈)((Fe_0.95Pt_0.05)₂As₂)₅ single crystal sample. At ambient pressure, the sample shows a metallic behavior at high temperatures and then increases with further decreasing temperature. The resistivity dip, which is associated with metal to semiconductor transition is monotonically suppressed by increasing pressure. In contrast, the superconducting transition temperature [Formula: see text] first increases with pressure and then decreases with further increasing pressure. Magnetization measurements, which gives the bulk [Formula: see text], show the same trend as the one obtained from resistivity measurements. An upward curvature is observed in the temperature dependence of the upper critical field [Formula: see text], which suggests the multiband nature of the superconductivity. The constructed temperature-pressure (T-P) phase diagram is very similar to the reported temperature-doping (T  -  x) phase diagram, suggesting the similar role played by pressure and chemical doping.

The clinical significance of perineural invasion in patients with de novo metastatic prostate cancer

BACKGROUND

The clinical value of perineural invasion (PNI) in patients with localized prostate cancer (PCa) is widely explored. However, its role in metastatic PCa (mPCa) remains unknown.

OBJECTIVES

We aim to investigate the clinical significance of PNI in patients with mPCa.

MATERIALS AND METHODS

Data of 515 mPCa patients between 2012 and 2018 were retrospectively studied. PNI and its intensity were identified by prostate biopsy. The prognostic value of PNI was evaluated by Kaplan-Meier curves and Cox proportional-hazards model.

RESULTS

Perineural invasion was detected in 170/515 (33.0%) cases. Among them 73/170 (42.9%) and 97/170 (57.1%) harbored unifocal PNI (uni-PNI) and multifocal PNI (multi-PNI), respectively. Compared to patients without PNI, those with PNI had statistically shorter castration-resistant PCa-free survival (CFS) and numerically shorter overall survival (OS) (mCFS: 15.4- vs. 18.5-Mo, p = 0.015; mOS: 63.8- vs. 71.4-Mo, p = 0.108). Patients harboring multi-PNI were associated with poorer clinical outcomes than those with uni-PNI (mCFS: 12.4- vs. 18.0-Mo, p = 0.040; mOS: 39.7-Mo vs. NR, p = 0.018) or those without PNI (mCFS: 12.4- vs. 18.5-Mo, p = 0.002; mOS: 39.7- vs. 71.4-Mo, p = 0.002). Totally, neither uni-PNI nor multi-PNI was an independent risk factor impacting survival outcomes in multivariate analyses. While remarkably, for patients with favorable/intermediate-risk mPCa, multi-PNI was an independent adverse prognosticator for both CFS and OS (CFS: HR: 1.705, 95% CI: 1.029-2.825, p = 0.038; OS: HR: 3.294, 95% CI: 1.464-7.413, p = 0.004).

DISCUSSION AND CONCLUSION

This study filled the blank of the clinical significance of PNI in mPCa. We found that multi-PNI could distinguish men with relatively poor prognosis from patients initially regarded as with favorable survival outcomes by other prognosticators, and thus, avoid disease underestimation in this group of patients. Our finding would help physicians have a deeper understanding of the heterogeneity of mPCa and make better individualized therapeutic strategy.