Molecular mechanism and therapeutic potential of YiQi FuMai injection in acute heart failure

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): The National Science Foundation for Distinguished Young Scholars of China

Background

 Acute heart failure (AHF) is a significant public health problem related to the high mortality and rehospitalization rate of patients. Although drug development is never interrupted, no single drug has been proven to play a decisive role in improving the survival of AHF patients. In China, multi-component traditional Chinese medicine has been widely used to treat AHF. As a Chinese herbal injection included in medical insurance, Yiqi Fumai Injection can reduce the level of NT-proBNP in AHF patients, improve heart function, and alleviate symptoms and signs related to heart failure. To further evaluate the therapeutic effect of Yiqi Fumai Injection on AHF, a multi-center, double-blind, randomized controlled trial that intends to recruit 1270 patients is being carried out in China. However, the mechanism of Yiqi Fumai Injection in the treatment of AHF has not been clarified. To further explore the underlying mechanism, we used systematic pharmacology methods to explore the potential molecular mechanisms of biologically active compounds.

Methods

 We used the databases of HERB, the Encyclopedia of Traditional Chinese Medicine (ETCM), the Comparative Toxicogenomics Database (CTD), Online Mendelian Inheritance in Man (OMIM), and GeneCards to predict the active ingredients and potential targets of Yiqi Fumai Injection in the treatment of AHF. STRING was used for PPI network construction and analysis. Cytoscape was used to build a network between Chinese medicine, ingredients and targets. The DAVID, GO, and KEGG databases were used to predict the potential pathways of Yiqi Fumai Injection for the treatment of AHF.

Results

 We obtained 31 active compounds of Yiqi Fumai Injection from HERB and ECTM databases. By overlapping targets between YQFMI and AHF, a total of 240 potential targets for Yiqi Fumai Injection to treat AHF were selected. According to the H-C-T network topology analysis, the core compounds include beta-sitosterol, Uridine, Guanosine, and Stigmasterol. Sixteen protein targets had significantly higher node degrees than the average in the PPI network, including AKT1, JUN, TNF, EDN1, CASP3, ESR1, DLG4, PTGS2, NOS3, IL1B, C3, AR, LEP, CNR1, CHRM2, and DRD2. The PPI results showed that the potential therapeutic targets of YQFMI were densely enriched in pathways related to endothelial function, neuromodulation, and lipid metabolism.The same results were shown in GO and KEGG pathway enrichment.

Conclusion

 Our results indicate that Yiqi Fumai Injection may achieve the goal of improving AHF-related symptoms by regulating the function of vascular endothelium and nerves and the biosynthetic pathway of lipid metabolism. These findings support previous studies and provide a reference for studying the mechanism of Yiqi Fumai Injection in the treatment of AHF. Abstract Figure.

First Measurement of Polarizations in the Decay D^{0}→ωφ

Using a data sample corresponding to an integrated luminosity of 2.93  fb^{-1} collected at a center-of-mass energy sqrt[s]=3.773  GeV by the BESIII detector, the decay D^{0}→ωϕ is observed for the first time. The branching fraction is measured to be (6.48±0.96±0.40)×10^{-4} with a significance of 6.3σ, where the first and second uncertainties are statistical and systematic, respectively. An angular analysis reveals that the ϕ and ω mesons from the D^{0}→ωϕ decay are transversely polarized. The 95% confidence level upper limit on longitudinal polarization fraction is set to be less than 0.24, which is inconsistent with current theoretical expectations and challenges our understanding of the underlying dynamics in charm meson decays.

[Clinical analysis of two brothers with Imerslund-Gräsbeck syndrome]

The clinical data of two children with Imerslund-Gräsbeck syndrome (IGS) who were admitted to the First Affiliated Hospital of Zhengzhou University in August 2019 was analyzed retrospectively. The two cases were siblings, aged 8 years and 8 months and 6 years and 2 months, respectively. These two boys had megaloblastic anemia, low level of vitamin B₁₂, hyperhomocysteinemia, accompanied by proteinuria and renal tubular injury, while they showed normal folate level and renal function. Blood tandem mass spectrometry and urine organic acid analysis suggested methylmalonic acidemia (MMA). The initial diagnosis was MMA with homocysteinemia. No known pathogenic gene mutation related to MMA was found by gene sequencing. Compound heterozygous variants of amnionless (AMN) gene were detected: c.43+5G>A and c.C717G. The corrected diagnosis was IGS. Both brothers were treated with long-term intramuscular injection of vitamin B₁₂. After follow-up for one year, these two cases had no clinical symptoms, and their blood indicators remained normal, but proteinuria and renal tubular injury persisted. Blood tandem mass spectrometry and urine organic acid analysis alone may easily lead to misdiagnosis, but combined with genetic testing can improve the accuracy of diagnosis of IGS. Lifelong parenteral vitamin B₁₂ replacement therapy can effectively reverse the clinical and biochemical results, but is uncertain in alleviating albuminuria and renal tubule injury. It's necessary to monitor the renal function regularly.

Measurement of the Absolute Branching Fraction of D_{s}^{+}→τ^{+}ν_{τ} via τ^{+}→e^{+}ν_{e}ν[over ¯]_{τ}

Using a dataset of 6.32  fb^{-1} of e^{+}e^{-} annihilation data collected with the BESIII detector at center-of-mass energies between 4178 and 4226 MeV, we have measured the absolute branching fraction of the leptonic decay D_{s}^{+}→τ^{+}ν_{τ} via τ^{+}→e^{+}ν_{e}ν[over ¯]_{τ}, and find B_{D_{s}^{+}→τ^{+}ν_{τ}}=(5.27±0.10±0.12)×10^{-2}, where the first uncertainty is statistical and the second is systematic. The precision is improved by a factor of 2 compared to the previous best measurement. Combining with f_{D_{s}^{+}} from lattice quantum chromodynamics calculations or the |V_{cs}| from the CKMfitter group, we extract |V_{cs}|=0.978±0.009±0.012 and f_{D_{s}^{+}}=(251.1±2.4±3.0)  MeV, respectively. Combining our result with the world averages of B_{D_{s}^{+}→τ^{+}ν_{τ}} and B_{D_{s}^{+}→μ^{+}ν_{μ}}, we obtain the ratio of the branching fractions B_{D_{s}^{+}→τ^{+}ν_{τ}}/B_{D_{s}^{+}→μ^{+}ν_{μ}}=9.72±0.37, which is consistent with the standard model prediction of lepton flavor universality.

Observation of D^{0}→K_{1}(1270)^{-}e^{+}ν_{e}

Using 2.93  fb^{-1} of e^{+}e^{-} collision data taken with the BESIII detector at a center-of-mass energy of 3.773 GeV, the observation of the D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} semileptonic decay is presented. The statistical significance of the decay D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is greater than 10σ. The branching fraction of D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is measured to be (1.09±0.13_{-0.16}^{+0.09}±0.12)×10^{-3}. Here, the first uncertainty is statistical, the second is systematic, and the third originates from the assumed branching fraction of K_{1}(1270)^{-}→K^{-}π^{+}π^{-}. The fraction of longitudinal polarization in D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is determined for the first time to be 0.50±0.19_{stat}±0.08_{syst}.

Molecular cloning and characterization of CD63 in common carp infected with koi herpesvirus

CD63 is a member of the four-transmembrane-domain protein superfamily and is the first characterized tetraspanin protein. In the present study, we cloned the common carp (Cyprinus Carpio) CD63 (ccCD63) sequence and found that the ccCD63 ORF contained 711 bp and encoded a protein of 236 amino acids. Homology analysis revealed that the complete ccCD63 sequence had 84.08% amino acid similarity to CD63 of Sinocyclocheilus anshuiensis. Subcellular localization analysis revealed that ccCD63 was localized in the cytoplasm. Quantitative real-time PCR (qRT-PCR) analysis indicated that ccCD63 was expressed in the gill, intestine, liver, spleen, brain and kidney, with higher expression in spleen and brain tissues than in the other examined tissues. After koi herpesvirus (KHV) infection, these tissues exhibited various expression levels of ccCD63. The expression level was the lowest in the liver and highest in the brain; the expression level in the brain was 8.7-fold higher than that in the liver. Furthermore, knockdown of ccCD63 promoted KHV infection. Moreover, ccCD63 was correlated with the regulation of RIG-I/MAVS/TRAF3/TBK1/IRF3 and may be involved in the antiviral response through the RIG-I viral recognition signalling pathway in a TRAF3/TBK1-dependent manner. Taken together, our results suggested that ccCD63 upregulated the interaction of KHV with the host immune system and suppressed the dissemination of KHV.

Retrospective Analysis on Traumatic Rupture of Intracranial Internal Carotid Artery in 11 Cases

Abstract

Objective To retrospectively analyze the characteristics of the traumatic rupture of intracranial internal carotid artery in order to provide reference for forensic expertise examination and identification. Methods A total of 11 autopsy cases of traumatic rupture of intracranial internal carotid artery were collected. The gender, age, cause of injury, blood loss on the scene, location of internal carotid artery rupture, hardening degree of the rupture of the wall, brain injury, blood ethanol content and cause of death were also recorded. Results All 11 cases died on the scene, of which 7 died from traffic accidents, 2 falls from height and 2 from bare handed injuries. None of the 11 victims suffered serious head and body surface injury. The internal carotid artery rupture in the 9 cases of traffic injury and fall from height injury occurred in the cavernous segment. In all these cases, there were transverse fractures of the middle cranial fossa with the carotid sulcus involved, and minor intracranial hemorrhage and brain contusion. In 2 cases of bare handed injuries, internal carotid artery rupture occurred in the ophthalmic artery segment, accompanied by fatal intracranial hemorrhage and diffuse axonal injury, but no skull fracture. All 11 cases showed full-thickness rupture of the vessel wall, and the long axis of the wounds was perpendicular to those of the artery. Conclusion The incidence of intracranial internal carotid artery rupture in high-energy trauma events such as traffic accidents and high falls deserves attention. Injuries of the cavernous segment or ophthalmic segment might be more common. The main injury mechanism of intracranial internal carotid artery rupture might be that the blood vessels were pulled and the bone fragments caused damage.

[Effects of duodenal ligation on gastroesophageal reflux and bleomycin-induced pulmonary fibrosis in rats]

Objective: To investigate the effects of duodenal ligation on gastroesophageal reflux and bleomycin-induced pulmonary fibrosis in rats. Methods: Wistar rats were randomized into the control (Ctrl) group, bleomycin (BLM) group, duodenal ligation (GER) group and duodenal ligation plus bleomycin treatment (BLM+GER) group. At day 0 (d0), duodenum ligation was performed in the GER and the BLM+GER group through an open-abdomen surgery at 1.0 cm below the pylorus by about 30% of the circumference. Meanwhile, sham operation was performed in the Ctrl and the BLM group with similar procedures to the above without ligation of the duodenum. At day 14, bleomycin solution (5 mg/kg, for the BLM and BLM+GER groups) or saline (for the Ctrl and GER groups) was intratracheally instilled. Rats were sacrificed at d28 or at d42. HE, Masson's trichrome or TUNEL staining was performed on lung sections of the groups. The levels of hyrdoxyproline (HYP) or malondialdehyde (MDA) were measured respectively by alkaline hydrolysis or thiobarbituric acid colorimetry. The levels of pepsin and cytokines in bronchoalveolar lavage fluid (BALF) samples were assessed by ELISA. Western blot or RT-PCR was used to quantify relative lung expression of proteins or mRNA, respectively. Results: Lungs of the GER group rats were presented with mild inflammatory cell infiltration. Alveolitis and lung fibrosis was prominent in the BLM group but even more severe in the BLM+GER group. Of the Ctrl, GER, BLM and BLM+GER group, the average numbers of apoptotic cells per each magnified field (×200) on d28 lung sections was (5.6±3.0), (6.4±5.3), (15.4±5.3) and (18.4±9.1), respectively (P=0.008); the proportion (%) of blue-stained area under Masson's trichrome at d42 was (21.5±2.8), (23.4±2.5), (34.0±5.8) and (41.3±2.9) (P<0.05); the HYP contents (mg/L) at d42 of each group was (0.77±0.01), (1.26±0.01), (2.02±0.01) and (2.39±0.01) (P<0.01); the BALF levels of MDA (μmol/L) at d42 were (0.51±0.09), (0.87±0.12), (1.40±0.31) and (1.71±0.12) (P<0.001), and differences of these three indices at d42 reached statistical significance when comparing the Ctrl or GER group with the BLM or BLM+GER group (all P<0.05). The levels of pepsin, pH, interleukin (IL)-1β, transforming growth factor (TGF)-β1 and HYP at d28 and d42 were statistically different between the GER group and the Ctrl group (all P<0.05). As compared with the BLM group, the values of TGF-β1, HYP, p-Smad3, vimentin, p-ERK1/2 and cleaved caspase-3 at d28 and d42 were different in the BLM+GER group (all P<0.05). At both d28 and d42, the BALF levels of pepsin and pH were statistically different between the BLM and the Ctrl group, or between the BLM+GER group and the GER group (all P<0.05). Conclusions: Gastroesophageal reflux is induced through duodenal ligation, which activates proinflammatory and profibrotic signals in the lungs and significantly aggravates bleomycin-induced lung injury and fibrosis. In addition, pulmonary fibrosis may induce or worsen the extent of reflux.

Three-dimensional bioprinting of artificial ovaries by an extrusion-based method using gelatin-methacryloyl bioink

PURPOSE

The aim of this study was to design and fabricate a three-dimensional (3D) printed artificial ovary.

METHODS

We first compared the printability of gelatin-methacryloyl (GelMA), alginate and GelMA-alginate bioinks, of which GelMA was selected for further investigation. The swelling properties, degradation kinetics and shape fidelity of GelMA scaffolds were characterized by equilibrium swelling/lyophilization, collagenase processing and micro-computed tomography evaluation. Commercial ovarian tumor cell lines (COV434, KGN, ID8) and primary culture ovarian somatic cells were utilized to perform cell-laden 3D printing, and the results were evaluated by live/dead assays and TUNEL detection. Murine ovarian follicles were seeded in the ovarian scaffold and their diameters were recorded every day. Finally, in vitro maturation was performed, and the ovulated oocytes were collected and observed.

RESULTS

Our results indicated that GelMA was suitable for 3D printing fabrication. Its scaffolds performed well in terms of hygroscopicity, degradation kinetics and shape fidelity. The viability of ovarian somatic cells was lower than that of commercial cell lines, suggesting that extrusion-based 3D culture fabrication is not suitable for primary ovarian cells. Nevertheless, the GelMA-based 3D printing system provided an appropriate microenvironment for ovarian follicles, which successfully grew and ovulated in the scaffolds. Metaphase II oocytes were also observed after in vitro maturation.

CONCLUSIONS

The GelMA-based 3D printing culture system is a viable alternative option for follicular growth, development and transfer. Accordingly, it shows promise for clinical application in the treatment of female endocrine and reproductive conditions.

Forensic Analysis of 105 Autopsy Cases of Psychiatric Patients

Abstract

Objective To provide reference for medical and health services and forensic expertise, the causes and manners of death of psychiatric patients were analyzed retrospectively. Methods A total of 105 autopsy cases of psychiatric patients accepted and settled by Institute of Forensic Science of Criminal Investigation Police University of China from 2004 to 2019 were collected. The cases were divided into four groups： disease death, suicidal death, accidental death and homicidal death. The common causes of death of each group were statistically analyzed and the differences in age, disease duration, body mass index （BMI） and gender among the groups were assessed. Results Of the 105 cases, 60 were male and 45 were female, the course of psychosis was （12.9±10.4） years, the age of the deceased was （51.3±11.4） years, and 61.0% was schizophrenic. There were 50 cases （47.6%） in the disease death group, in which the psychiatric patients were the oldest and had the longest course of psychosis and lowest BMI. Pulmonary thromboembolism, respiratory infections, and cardiogenic disease were the most common causes of death in the group. There were 26 accidental deaths （24.8%）, among which traffic accidents were the most common cause of death. There were 15 homicidal deaths （14.3%）, all of which were male, with craniocerebral injury being the most common cause of death. There were 14 suicidal deaths （13.3%）. In suicidal death group, the age of the deceased was the youngest, the course of psychosis was the shortest and falling from the height was the most common way to commit suicide. Conclusion Understanding the common causes of death of psychiatric patients may contribute to developing measures to reduce the mortality rate of the population. It is necessary to investigate the age, course of psychosis and gender of the deceased when assessing the manner of death.

[Analysis of clinical characteristics of middle ear osteoma at different locations]

Objective: To explore the clinical characteristics, intervention and treatment of tympanic osteoma at different locations. Methods: The medical history, audiological and imaging examination, operation and follow-up results of two patients with tympanic osteoma at different sites were reviewed and summarized. Furthermore, the clinical characteristics and interventions of 36 patients reported in literatures with tympanic osteomas were also summarized and analyzed. Results: Osteoma of the two patients collected in this study located at promontory and incus respectively;both of them presented with intact tympanum and conductive deafness, without obvious etiology or predisposing factor. Both of them underwent surgeries and the hearing improved significantly. For patient one, the ossicular chain was intact and restored to activity after removed the osteoma. For patient two, an artificial ossicle was implanted after removed the osteoma and incus. In the 36 patients reported in literatures, the average age was 26.5 years, and 39.47% of them located at promontory; in addition, the main symptoms of them were progressive hearing loss, tinnitus and ear stuffy. Conclusions: Patients with tympanic osteoma are characterized by conduction deafness with intact tympanic membrane, and the most common lesion is promontory. Hearing can be restored by excision of the osteoma and maintenance or reconstruction of the ossicle chain.

Shear stress-induced MMP1 and PDE2A expressions in coronary atherosclerosis

AIM

Biomechanical stress plays an essential role in coronary atherosclerosis (CAS), however, inter-relations between mechanical conditions and gene expressions remain unclear.

METHODS

We constructed finite element model of CAS to map human wall shear stress (WSS). Biopsy aortic tissue samples were obtained from 3 CAS patients. Gene expression pattern in CAS was analyzed by GEO datasets. Immunofluorescence staining and western blot confirmed protein expression and localization.

RESULTS

Peak WSS was significantly increased in the vessel stenosis of CAS at 0.25 s (mean 55.1 Pa). Analyses results of GSE76275 showed matrix metalloproteinases1 (MMP1) and phosphodiesterase-2A (PDE2A) up-regulation in endothelial shear responsiveness, which was further validated and localized in vascular endothelial cells, smooth muscle cells and other cells by double immunofluorescence staining. Western blotting assay demonstrated up-regulation of MMP1 and PDE2A expression dependent on the WSS.

CONCLUSIONS

MMP1 and PDE2A up-regulations rely on increased WSS in development and risk of CAS, suggesting that their elevation may be potential target for diagnosis and treatment (Fig. 3, Ref. 28).

Observation of a Near-Threshold Structure in the K^{+} Recoil-Mass Spectra in e^{+}e^{-}→K^{+}(D_{s}^{-}D^{*0}+D_{s}^{*-}D^{0})

We report a study of the processes of e^{+}e^{-}→K^{+}D_{s}^{-}D^{*0} and K^{+}D_{s}^{*-}D^{0} based on e^{+}e^{-} annihilation samples collected with the BESIII detector operating at BEPCII at five center-of-mass energies ranging from 4.628 to 4.698 GeV with a total integrated luminosity of 3.7  fb^{-1}. An excess of events over the known contributions of the conventional charmed mesons is observed near the D_{s}^{-}D^{*0} and D_{s}^{*-}D^{0} mass thresholds in the K^{+} recoil-mass spectrum for events collected at sqrt[s]=4.681  GeV. The structure matches a mass-dependent-width Breit-Wigner line shape, whose pole mass and width are determined as (3982.5_{-2.6}^{+1.8}±2.1)  MeV/c^{2} and (12.8_{-4.4}^{+5.3}±3.0)  MeV, respectively. The first uncertainties are statistical and the second are systematic. The significance of the resonance hypothesis is estimated to be 5.3  σ over the contributions only from the conventional charmed mesons. This is the first candidate for a charged hidden-charm tetraquark with strangeness, decaying into D_{s}^{-}D^{*0} and D_{s}^{*-}D^{0}. However, the properties of the excess need further exploration with more statistics.

[Long-term outcomes of intravascular ultrasound-guided drug-eluting stent implantation in patients with chronic kidney disease: ULTIMATE CKD subgroup analysis]

Objective: To explore the long-term effect of intravascular ultrasound (IVUS) guidance on patients with chronic kidney disease (CKD) undergoing drug-eluting stent (DES) implantation. Methods: Data used in this study derived from ULTIMATE trial, which was a prospective, multicenter, randomized study. From August 2014 to May 2017, 1 448 patients with coronary heart disease undergoing DES implantation were selected from 8 domestic centers and randomly divided into two groups in the ratio of 1∶1 (IVUS or coronary angiography guided stent implantation). A total of 1 443 patients with the baseline serum creatine available were enrolled. The patients were divided into CKD group and non CKD group. CKD was defined as the estimated glomerular filtration rate (eGFR) derived from Cockcroft Gault (CG) formula< 60 ml·min^-1·1.73 m^-2 for at least 3 months. Primary endpoint of this study was target vessel failure (TVF) at 3 years, including cardiac death, target vessel myocardial infarction, and clinically-driven target vessel revascularization. Kaplan Meier method was used for survival analysis, and log rank test was used to compare the occurrence of end-point events in each group. Cox proportional hazards model was used to calculate HR and 95%CI, and interaction was tested. Multivariate Cox regression was used to analyze the independent influencing factors of TVF. Results: A total of 1 443 patients with coronary heart disease were enrolled in this study, including 349 (24.2%) patients in CKD group and 1 094 patients in non CKD group. In CKD group, IVUS was used to guide stent implantation in 180 cases and angiography was used in 169 cases; in non CKD group, IVUS was used to guide stent implantation in 543 cases and angiography was used in 551 cases. Three-year clinical follow-up was available in 1 418 patients (98.3%). The incidence of TVF in CKD group was 12.0% (42/349), which was higher than that in non CKD group (7.4% (81/1 094) (P = 0.01). The difference was mainly due to the higher cardiac mortality in CKD group (4.6% (16/349) vs. 1.5% (16/1094), P<0.001). In CKD group, the incidence of TVF in patients who underwent IVUS guided stent implantation was lower than that in angiography guided stent implantation (8.3% (15/180) vs. 16.0% (27/169), P = 0.03). There was no significant difference in the incidence of TVF between IVUS guided stent implantation and angiography guided stent implantation in non CKD group (5.9% (32/543) vs. 8.9% (49/551), P = 0.06), and there was no interaction (P = 0.47). Multivariate Cox regression analysis showed that IVUS guidance (HR = 0.56, 95%CI 0.39-0.81, P = 0.002), CKD (HR = 1.83, 95%CI 1.17-2.87, P = 0.010) and stent length (every 10 mm increase) (HR = 1.11, 95%CI 1.04-1.19, P = 0.002) were independent risk factors for TVF within 3 years after DES implantation. Conclusions: CKD patients undergoing DES implantation are associated with a higher risk of 3-year TVF. More importantly, the risk of TVF could be significantly decreased through IVUS guidance in comparison with angiography guidance in patients with CKD.

[Agreement of EV-A71 neutralization assay: serial 4-fold versus 2-fold dilution comparison]

Objective: To evaluate consistency between 2-fold serial and 4-fold serial diluted neutralization tests against Enterovirus A71 (EV-A71) in estimating titer, Geometric mean titer (GMT), seroprevalence, and seroincidence. Methods: Based on a prospective cohort of 1-9 years old children, mothers and infants established in Anhua County, Hunan Province, during 2013-2018, from which 92 participants with a total of 386 blood specimens were sampled and tested with a 2-fold serial dilution and a 4-fold serial dilution neutralization tests against EV-A71 at the same time. Agreement was estimated using the Bland-Altman method. Stratified analysis was conducted to estimate effect dilution approach on GMT, seroprevalence and seroincidence. Results: The mean difference (0.04, 95%CI:-0.02-0.10) between the two dilution approaches was not significant. However, the limits of agreement (LOA) (-1.12-1.21), with the 95% confidence interval of upper LOA (1.10-1.31) and of lower LOA (-1.22--1.02), significantly exceeded the Clinic accept interval (-1, 1) indicating insufficient agreement between the two approaches in practice. While the dilution approaches did not affect estimates of GMT of the total population and the positive population, and seroincidence with seroconversion only, the differences were 2, 6 and 2%, respectively (P>0.05). Estimates of seroincidence with at least 4-fold increase and seroconversion/4-fold increase were significantly higher using a 4-fold dilution neutralization test compared to the 2-fold dilution neutralization test with 8% (95%CI: 1%-12%) and 9% (95%CI: 1%-17%), respectively. Conclusion: The 2-dilution and 4-dilution neutralization tests yielded comparable results when estimating the population's GMT; however, the difference between the two is not negligible when assessing the seroincidence.

Recent development and new insight of diversification and symbiosis specificity of legume rhizobia: mechanism and application

Currently, symbiotic rhizobia (sl., rhizobium) refer to the soil bacteria in α- and β-Proteobacteria that can induce root and/or stem nodules on some legumes and a few of nonlegumes. In the nodules, rhizobia convert the inert dinitrogen gas (N₂ ) into ammonia (NH₃ ) and supply them as nitrogen nutrient to the host plant. In general, this symbiotic association presents specificity between rhizobial and leguminous species, and most of the rhizobia use lipochitooligosaccharides, so called Nod factor (NF), for cooperating with their host plant to initiate the formation of nodule primordium and to inhibit the plant immunity. Besides NF, effectors secreted by type III secretion system (T3SS), exopolysaccharides and many microbe-associated molecular patterns in the rhizobia also play important roles in nodulation and immunity response between rhizobia and legumes. However, the promiscuous hosts like Glycine max and Sophora flavescens can nodulate with various rhizobial species harbouring diverse symbiosis genes in different soils, meaning that the nodulation specificity/efficiency might be mainly determined by the host plants and regulated by the soil conditions in a certain cases. Based on previous studies on rhizobial application, we propose a '1+n-N' model to promote the function of symbiotic nitrogen fixation (SNF) in agricultural practice, where '1' refers to appreciate rhizobium; '+n' means the addition of multiple trace elements and PGPR bacteria; and '-N' implies the reduction of chemical nitrogen fertilizer. Finally, open questions in the SNF field are raised to future think deeply and researches.

[Visualization analysis of liver fibrosis diagnosis based on Citespace software]

Objective: To explore the research hotspots and development trends in the field of liver fibrosis diagnosis by using visualization methods. Methods: The relevant literatures on liver fibrosis diagnosis were downloaded from the China National Knowledge Infrastructure database. CiteSpace 5.3.R6 software was used to analyze the authors, institutions and key node information to explore the main research groups, institutions and research hotspots and development trends of this field. Results: The analysis showed that the main research authors were Cai Weimin, Guo Qiyong, etc. The main research institutions included were Shengjing Hospital affiliated to China Medical University, Shenzhen Third People's Hospital, etc. The current diagnosis of liver fibrosis was mainly focused on invasive (liver biopsy) and non-invasive (serology, imaging) diagnosis. The non-invasive diagnosis may be the research hotspot and direction of liver fibrosis in the future. Conclusion: The visualization analysis of liver fibrosis diagnosis by CiteSpace software can quickly and intuitively understand the basic knowledge and evolution of this field, as well as the main research directions, hot spots and future development trends.

[Analysis of pregnancy outcomes of D6 single blastocyst transplantation in fresh and frozen-thawed cycles]

Objective: To compare the main clinical outcomes of Day 6 (D6) single blastocyst transplantation in fresh and frozen-thawed cycles. Methods: The data of fresh blastocyst transplantation patients and frozen-thawed blastocyst transplantation patients from January 2013 to December 2017 were retrospectively analysed. Fresh blastocyst transplantation and frozen-thawed blastocyst transplantation were matched in a ratio of 1∶3 by using propensity score matching, the matching factors included age, body mass index, thickness of endometrium and blastocyst grade. Totally 180 cases were included in the fresh cycle group and 540 cases in the frozen-thawed cycle group. Results: There was no significant difference in basal FSH between the two groups [(6.9±2.5) versus (6.4±3.8) U/L, P=0.334]. The positive rate of hCG in D6 blastocyst fresh cycle transplantation group [32.8%(59/180) versus 48.1%(260/540)], clinical pregnancy rate [28.9%(52/180) versus 43.5%(235/540)] and live birth rate [21.1%(38/180) versus 32.2%(174/540)] were lower than those of frozen-thawed cycle group (all P<0.05). The miscarriage rate was higher [26.9%(14/52) versus 24.7%(58/235)], but there was no statistical difference (P>0.05). Conclusions: The clinical pregnancy outcome of D6 single blastocyst frozen-thawed cycle transplantation is better than that of fresh cycle. In order to obtain better clinical outcomes, frozen-thawed cycle transplantation of blastocysts formed on the 6th day is recommended.

[Current status of anti-reflux surgery of proximal gastrectomy for esophagogastric junction tumor]

In recent years, the overall incidence of gastric cancer has been decreasing worldwide, while the incidence of the esophagogastric junction tumor is increasing year by year. With the progress of the diagnostic technology of upper gastrointestinal tumors and the gradual popularization of early cancer screening, the detection rate of early esophagogastric junction tumor keeps increasing. Therefore, in recent years, the clinical application of gastric function preserving surgery is gradually increasing. As an important part of the surgical treatment strategy of esophagogastric junction tumors, proximal gastrectomy has attracted more and more attention with the confirmation of oncological safety. Compared with total gastrectomy, patients after proximal gastrectomy have better nutritional status and quality of life. However, the high incidence of reflux esophagitis after traditional proximal gastrectomy has seriously affected the quality of life of patients, and also hindered the application of proximal gastrectomy in esophagogastric junction tumors. How to reduce the occurrence of reflux esophagitis after proximal gastrectomy by optimizing the method of digestive tract reconstruction has been a big challenge in clinical practice. This article reviews the current methods of anti-reflux surgery for proximal gastrectomy for esophagogastric junction tumors, aiming to provide a reference for choosing a reasonable anti-reflux surgery.

[The relationship between soluble silicate acid in drinking water and food and human health]

Silicon was once considered a biologically inert element, but recent research has shown its value for human health.Soluble silicic acid is the available form of silicon in human body. This paper reviews the absorption, distribution and metabolic characteristics of dietary soluble silicic acid in human body, as well as its relationship with human health.Available data show that it has lots of supporting evidences that dietary soluble silicic acid can prevent osteoporosis, maintain vascular health, improve the symptoms of Alzheimer's disease and multiple sclerosis.Its unique crosslinking ability and antagonism to toxic aluminum play a crucial role. In the early stage of human life, there is a strong demand for silicon, and the level of silicon in the aged is generally reduced, suggesting that pregnant women and old people should pay attention to the intake of soluble silicic acid. It is suggested to strengthen the basic and applied research on dietary soluble silicic acid,and gradually establish the relevant nutrition and hygiene standards.

[Debridement combined with negative-pressure wound therapy and local flap for treating a case of stingray sting]

On January 10, 2018, a 35-year-old male patient with a 3 day stingray stinger injury in his left thigh was admitted to Xuzhou Central Hospital. At the time of admission, the patient's left thigh was red, swollen, and painful. On the day of admission, the patient underwent emergency operation in the outpatient operating room for local debridement to remove the infected and necrotic tissue. After the routine dressing change and the wound got better, surgical debridement and negative-pressure wound therapy were performed, and finally local flap was used to repair the wound. On the 14th day after the flap repair operation, the suture was removed and the patient was discharged. After half a year follow-up, the appearance of the operation area recovered well. This case suggests that the timely and correct pre-hospital treatment, thorough and timely debridement, and systemic antibiotic application are important means to reduce further injury of toxin. The local flap can achieve satisfactory result on wound healing after the wound bed is prepared by negative-pressure wound therapy.