[Efficacy of thymectomy in patients with non-thymoma myasthenia gravis]

Objective: To compare the efficacy between thymectomy plus prednisone and prednisone alone in patients with non-thymoma myasthenia gravis (MG). Methods: Thirty generalized MG patients without thymoma who underwent thymectomy were collected as the operation group, and thirty-nine patients without thymectomy who were treated with prednisone alone were matched as the control group. The start point was the enrollment time and the endpoint event was the "clinical remission" (including complete stabilization remission, drug remission, and poor performance). The survival curve was used to analyze the difference of endpoint event time between the two groups. Besides, a 12-month follow-up study was conducted to compare relevant clinical indicators between the two groups. Results: There was no significant difference in the occurrence time of endpoint events between the two groups (P=0.614). After 6-month follow-up, no significant differences were found in clinical remission rate, the dosage of pyridostigmine bromide and prednisone, the peak dosage of prednisone, the use of other immunosuppressive medications and the rate of hospitalization for exacerbation of disease between the two groups (all P>0.05). After 12-month follow-up, the dosage of prednisone and pyridostigmine in the operation group was significantly lower than that in the control group (5(0,10)mg/d vs 7.5(5,10)mg/d and 30(0,105)mg/d vs 90(15,180)mg/d; P=0.038, 0.032). Conclusion: In patients with mild to moderate non-thymoma generalized MG, thymectomy does not achieve faster remission, but it does reduce the long-term dosage of prednisone and bromopyrazine.

Polysaccharides from Armillariella tabescens mycelia ameliorate renal damage in type 2 diabetic mice

Diabetic kidney disease (DKD), accompanied by chronic low-grade inflammation, is one of the most common complications of diabetes. Armillariella tabescens has potent anti-inflammatory and immunomodulatory properties. The purpose of the present study was to investigate the effects of polysaccharides from Armillariella tabescens mycelia (AT) on the kidney in type 2 diabetic mice and explore the underlying mechanism. The mice were randomized into 4 groups: normal control (NC), diabetic control (DC), DC + 200 mg/kg AT (LAT), and DC + 400 mg/kg AT (HAT). The results showed that compared with the NC group, the levels of fasting blood glucose, renal function-related indices, and serum pro-inflammatory mediators including lipopolysaccharide (LPS), interleukin (IL)-1β, and IL-18 were elevated; the renal morphopathological alterations, oxidative stress, and nucleotide-binding oligomerization domain-like receptor protein 3 inflammasome-mediated inflammation and renal fibrosis were aggravated; the intestinal microbiota dysbiosis and colonic inflammation and barrier dysfunction were deteriorated in the DC group. After supplementation with AT, the aforementioned indices were ameliorated in the AT treatment groups, especially in the HAT group. In conclusion, these results demonstrated that modulating the intestinal microbiota and inflammatory reaction was implicated in the effects of AT against DKD in mice.

Inhibition of Circulating miR-194-5p Reverses Osteoporosis through Wnt5a/β-Catenin-Dependent Induction of Osteogenic Differentiation

Mesenchymal stem cells (MSCs) critically contribute to bone formation, and proper induction of osteogenic differentiation can lead to an increase in bone mass. In the present study, we reported that an increased miR-194-5p level in plasma is inversely related to the degree of bone formation in osteoporosis patients. We also noted that increased miR-194-5p in the MSCs of ovariectomized (OVX) mice and agomiR-194-5p manipulation of miR-194-5p significantly suppressed bone formation, both in aged and OVX mice. Furthermore, our in vitro study showed that overexpression of miR-194-5p suppresses osteogenic differentiation, as evidenced by the decreased bone formation marker genes and matrix mineralization. The luciferase assay indicated that Wnt family member 5a (Wnt5a) is a target gene of miR-194-5p that positively regulates osteogenic differentiation. Collectively, these data indicated that miR-194-5p inhibition may be a potential strategy for osteoporosis prevention.

PRL3 enhances T-cell acute lymphoblastic leukemia growth through suppressing T-cell signaling pathways and apoptosis

T cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy of thymocytes and is largely driven by the NOTCH/MYC pathway. Yet, additional oncogenic drivers are required for transformation. Here, we identify protein tyrosine phosphatase type 4 A3 (PRL3) as a collaborating oncogenic driver in T-ALL. PRL3 is expressed in a large fraction of primary human T-ALLs and is commonly co-amplified with MYC. PRL3 also synergized with MYC to initiate early-onset ALL in transgenic zebrafish and was required for human T-ALL growth and maintenance. Mass spectrometry phosphoproteomic analysis and mechanistic studies uncovered that PRL3 suppresses downstream T cell phosphorylation signaling pathways, including those modulated by VAV1, and subsequently suppresses apoptosis in leukemia cells. Taken together, our studies have identified new roles for PRL3 as a collaborating oncogenic driver in human T-ALL and suggest that therapeutic targeting of the PRL3 phosphatase will likely be a useful treatment strategy for T-ALL.

Inhibition of circulating exosomal microRNA-15a-3p accelerates diabetic wound repair

Diabetic foot ulcers are a common complication of diabetes, and are usually incurable in the clinic. Exosomes (carriers that transfer endogenous molecules) from diabetic patients' blood have been demonstrated to suppress diabetic wound repair. In this study, we investigated the effects of circulating exosomal microRNA-15a-3p (miR-15a-3p) on diabetic wound repair. Exosomes were extracted from diabetic patients' blood, and were found to inhibit diabetic wound repair in vitro and in vivo. miR-15a-3p was upregulated in diabetic exosomes, and impaired wound healing. When miR-15a-3p was knocked down in diabetic exosomes, their negative effects were partially reversed both in vitro and in vivo. NADPH oxidase 5 (NOX5) was identified as a potential target of miR-15a-3p, and the inhibition of NOX5 reduced the release of reactive oxygen species, thereby impairing the functionality of human umbilical vein endothelial cells. In summary, inhibition of circulating exosomal miR-15a-3p accelerated diabetic wound repair by activating NOX5, providing a novel therapeutic target for diabetic foot ulcer therapy.

Association study of SNCA gene polymorphisms with schizophrenia in a Chinese North Han population

OBJECTIVE

Previous studies suggested that the alpha-synapse protein (SNCA) gene and its coding product α-synuclein (α-Syn) may play a role in the pathogenesis of neurodegenerative diseases. The mutation of SNCA can influence the formation of nerve fibers and the function of dopaminergic neurons, and that may be related to addictive behavior, such as alcohol dependence. SNCA may overlap with the pathogenesis of schizophrenia and Parkinson's disease or alcohol dependence associated with the dopamine pathway. The aim was to determine the association between three SNCA SNPs (rs3822086C/T, rs11931074G/T, and rs356219A/G) and schizophrenia in a Chinese North Han population.

PATIENTS AND METHODS

A total of 878 subjects, with or without schizophrenia, were included in our study. DNA purification, Polymerase Chain Reaction (PCR) amplification, and subsequent restriction fragment length polymorphism (RFLP) analysis were manipulated to determine genotypes.

RESULTS

Between the schizophrenia group and healthy group, neither the genotype nor allele frequencies of rs3822086C/T, rs11931074G/T, or rs356219A/G differed significantly in either the total sample or the subgroups. In the haplotype analysis, the ATT and GTT haplotype frequencies differed significantly between the patients and controls in the total sample (χ2=6.052, p=0.0139; χ2=4.508, p=0.0337). In the female subgroup, the ATT haplotype frequency differed significantly between the patients and controls (χ2=4.219, p=0.04).

CONCLUSIONS

There was no association between SNCA polymorphisms and schizophrenia in the North Han Chinese population, and the ATT haplotype may be a susceptibility factor for schizophrenia.

Saliva exosomes-derived UBE2O mRNA promotes angiogenesis in cutaneous wounds by targeting SMAD6

Background

Enhancing angiogenesis is critical for accelerating wound healing. Application of different types of exosomes (Exos) to promote angiogenesis represents a novel strategy for enhanced wound repair. Saliva is known to accelerate wound healing, but the underlying mechanisms remain unclear.

Results

Our results have demonstrated that saliva-derived exosomes (saliva-Exos) induce human umbilical vein endothelial cells (HUVEC) proliferation, migration, and angiogenesis in vitro, and promote cutaneous wound healing in vivo. Further experiments documented that Ubiquitin-conjugating enzyme E2O (UBE2O) is one of the main mRNAs of saliva-Exos, and activation of UBE2O has effects similar to those of saliva-Exos, both in vitro and in vivo. Mechanistically, UBE2O decreases the level of SMAD family member 6 (SMAD6), thereby activating bone morphogenetic protein 2 (BMP2), which, in turn, induces angiogenesis.

Conclusions

The present work suggests that administration of saliva-Exos and UBE2O represents a promising strategy for enhancing wound healing through promotion of angiogenesis.

Size-dependent influence of NOx on the growth rates of organic aerosol particles

Atmospheric new-particle formation (NPF) affects climate by contributing to a large fraction of the cloud condensation nuclei (CCN). Highly oxygenated organic molecules (HOMs) drive the early particle growth and therefore substantially influence the survival of newly formed particles to CCN. Nitrogen oxide (NOx) is known to suppress the NPF driven by HOMs, but the underlying mechanism remains largely unclear. Here, we examine the response of particle growth to the changes of HOM formation caused by NOx. We show that NOx suppresses particle growth in general, but the suppression is rather nonuniform and size dependent, which can be quantitatively explained by the shifted HOM volatility after adding NOx. By illustrating how NOx affects the early growth of new particles, a critical step of CCN formation, our results help provide a refined assessment of the potential climatic effects caused by the diverse changes of NOx level in forest regions around the globe.

M2 Macrophagy-derived exosomal miRNA-5106 induces bone mesenchymal stem cells towards osteoblastic fate by targeting salt-inducible kinase 2 and 3

BACKGROUND

Osteoblast differentiation is a vital process for fracture healing, and exosomes are nanosized membrane vesicles that can deliver therapeutic drugs easily and safely. Macrophages participate in the regulation of various biological processes in vivo, and macrophage-derived exosomes (MD-Exos) have recently been a topic of increasing research interest. However, few study has explored the link between MD-Exos and osteoblast differentiation. Herein, we sought to identify miRNAs differentially expressed between M1 and M2 macrophage-derived exosomes, and to evaluate their roles in the context of osteoblast differentiation.

RESULTS

We found that microRNA-5106 (miR-5106) was significantly overexpressed in M2 macrophage-derived exosomes (M2D-Exos), while its expression was decreased in M1 macrophage-derived exosomes (M1D-Exos), and we found that this exosomal miRNA can induce bone mesenchymal stem cell (BMSC) osteogenic differentiation via directly targeting the Salt-inducible kinase 2 and 3 (SIK2 and SIK3) genes. In addition, the local injection of both a miR-5106 agonist or M2D-Exos to fracture sites was sufficient to accelerate healing in vivo.

CONCLUSIONS

Our study demonstrates that miR-5106 is highly enriched in M2D-Exos, and that it can be transferred to BMSCs wherein it targets SIK2 and SIK3 genes to promote osteoblast differentiation.

Methyltransferase-like 3-mediated N6-methyladenosine modification of miR-7212-5p drives osteoblast differentiation and fracture healing

N6-methyladenosine (m6A) modification has been reported in various diseases and implicated in increasing numbers of biological processes. However, previous studies have not focused on the role of m6A modification in fracture healing. Here, we demonstrated that m6A modifications are decreased during fracture healing and that methyltransferase-like 3 (METTL3) is the main factor involved in the abnormal changes in m6A modifications. Down-regulation of METTL3 promotes osteogenic processes both in vitro and in vivo, and this effect is recapitulated by the suppression of miR-7212-5p maturation. Further studies have shown that miR-7212-5p inhibits osteoblast differentiation in MC3T3-E1 cells by targeting FGFR3. The present study demonstrated an important role of the METTL3/miR-7212-5p/FGFR3 axis and provided new insights on m6A modification in fracture healing.

Rapid and visual detection of 2019 novel coronavirus (SARS-CoV-2) by a reverse transcription loop-mediated isothermal amplification assay

OBJECTIVE

To evaluate a reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and compare it with RT-PCR.

METHODS

We designed primers specific to the orf1ab and S genes of SARS-CoV-2. Total viral RNA was extracted using the QIAamp Viral RNA Mini Kit. We optimized the RT-LAMP assay, and evaluated it for its sensitivity and specificity of detection using real-time turbidity monitoring and visual observation.

RESULTS

The primer sets orf1ab-4 and S-123 amplified the genes in the shortest times, the mean (±SD) times were 18 ± 1.32 min and 20 ± 1.80 min, respectively, and 63°C was the optimum reaction temperature. The sensitivities were 2 × 10¹ copies and 2 × 10² copies per reaction with primer sets orf1ab-4 and S-123, respectively. This assay showed no cross-reactivity with 60 other respiratory pathogens. To describe the availability of this method in clinical diagnosis, we collected 130 specimens from patients with clinically suspected SARS-CoV-2 infection. Among them, 58 were confirmed to be positive and 72 were negative by RT-LAMP. The sensitivity was 100% (95% CI 92.3%-100%), specificity 100% (95% CI 93.7%-100%). This assay detected SARS-CoV-2 in a mean (±SD) time of 26.28 ± 4.48 min and the results can be identified with visual observation.

CONCLUSION

These results demonstrate that we developed a rapid, simple, specific and sensitive RT-LAMP assay for SARS-CoV-2 detection among clinical samples. It will be a powerful tool for SARS-CoV-2 identification, and for monitoring suspected patients, close contacts and high-risk groups.

CTXA hip: the effect of partial volume correction on volumetric bone mineral density data for cortical and trabecular bone

This study compares the results of computed tomography X-ray absorptiometry (CTXA) hip volumetric BMD (vBMD) analyses of cortical and trabecular bone with and without partial volume correction. For cortical bone in some circumstances, corrected cortical volumes were negative and corrected vBMD was very high. For trabecular bone, the correction effects are smaller. CTXA volumetric data should be interpreted with caution.

PURPOSE

Previous studies have reported concerns about the reliability of CTXA hip cortical vBMD measurements generated using partial volume (PV) correction (the "default" analysis, with cortical PV correction). To date, no studies have examined the results of the alternative ("new") analysis (with trabecular PV correction). This study presents in vivo and phantom data comparing the corrected and uncorrected data for cortical and trabecular bone respectively.

METHODS

We used the commercial QCTPro CTXA software to analyze CT scans of 129 elderly Chinese men and women and an anthropomorphic European Proximal Femur phantom (EPFP) and accessed data for two alternative scan analyses using the database dump utility. The CTXA software gives the user two methods of performing the PV correction: (1) a default analysis in which only cortical bone results are corrected; (2) a new analysis in which only trabecular bone results are corrected. Both methods are based on a numerical recalculation of vBMD values without any change in volume of interest (VOI) placement.

RESULT

In vivo, the results of the two analyses for integral bone were the same while cortical and trabecular results were different. PV correction of cortical bone led to a decrease of cortical volume for all four VOIs: total hip (TH), femoral neck (FN), trochanter (TR), and intertrochanter (IT) volumes were reduced on average by 7.8 cm³, 0.9 cm³, 2.5 cm³, and 4.3 cm³ respectively. For TR, where cortex was thinnest, average corrected cortical volume was negative (- 0.4± 1.3 cm³). Corrected cortical vBMD values were much larger than uncorrected ones for TH, FN, and IT. Scatter plots of corrected cortical vBMD against cortical bone thickness showed that elevated results correlated with thinner cortices. When trabecular bone was corrected for the PV effect, trabecular volumes of TH, FN, TR, and IT were reduced on average by 7.9 cm³, 0.8 cm³, 2.6 cm³, and 4.4 cm³ respectively, while vBMD measurements were increased correspondingly. The trabecular volume and vBMD measurements of the two datasets both had highly positive correlations. For the EPFP, the PV-corrected FN data deviated from the nominal phantom value, but was closer for the TR and IT VOIs. Both corrected and uncorrected data overestimated trabecular vBMD, with the corrected results showing greater deviation from nominal values.

CONCLUSION

The default and new CTXA analyses for volumetric data generate different results, both for cortical and trabecular bone. For cortical bone, the uncorrected results are subject to partial volume effects but the correction method of the default analysis overcorrects the effect leading to in part unreasonable results for cortical bone volume and BMD. For trabecular bone, the correction effects are smaller. CTXA volumetric data should be interpreted with caution.

The lncRNA Rhno1/miR-6979-5p/BMP2 Axis Modulates Osteoblast Differentiation

The roles of long non-coding RNAs (lncRNAs) and micro RNAs (miRNAs) as regulators of mRNA expression in various diseases have recently been reported. Osteoblast differentiation is the vital process which mediates bone formation and fracture healing. In present study, we found microRNA-6979-5p (miR-6979-5p) to be the most differentially expressed miRNA between normal bone and calluses of mice, and overexpression of miR-6979-5p was negatively associated with osteoblast differentiation. Through luciferase assays, we found evidence that bone morphogenetic protein 2 (BMP2) is a miR-6979-5p target gene that positively regulates osteoblast differentiation. We further identified the lncRNA Rhno1 as a competing endogenous RNA (ceRNA) of miR-6979-5p, and we verified that it was able to influence osteoblast differentiation both in vitro and in vivo. In summary, our data indicates that the lncRNA Rhno1/miR-6979-5p/BMP2 axis is a significant regulatory mechanism controlling osteoblast differentiation, and it may thus offer a novel therapeutic strategy for fracture healing.

Identification of key microRNAs and target genes for the diagnosis of bone nonunion

A number of recent studies have highlighted the causes of bone nonunion (BN), however, the rate of BN incidence continues to rise and available therapeutic options to treat this condition remain limited. Thus, to prevent disease progression and improve patient prognosis, it is vital that BN, or the risk thereof, be accurately identified in a timely manner. In the present study, bioinformatics analyses were used to screen for the differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs) between patients with BN and those with bone union, using data from the Gene Expression Omnibus database. Furthermore, clinical samples were collected and analyzed by reverse transcription‑quantitative PCR and western blotting. In vitro and in vivo experiments were carried out to confirm the relationship between BN and the DEGs of interest, in addition to being used to explore the underlying molecular mechanism of BN. Functional enrichment analysis of the downregulated DEGs revealed them to be enriched for genes associated with 'ECM‑receptor interactions', 'focal adhesion', 'and the calcium signaling pathway'. When comparing DEM target genes with these DEGs, nine DEGs were identified as putative DEM targets, where hsa‑microRNA (miR)‑1225‑5p‑CCNL2, hsa‑miR‑339‑5p‑PRCP, and hsa‑miR‑193a‑3p‑mitogen‑activated protein kinase 10 (MAPK10) were the only three pairs which were associated with decreased gene expression levels. Furthermore, hsa‑miR‑193a‑3p was demonstrated to induce BN by targeting MAPK10. Collectively, the results of the present study suggest that hsa‑miR‑193a‑3p may be a viable biomarker of BN.

LncRNA KCNQ1OT1 accelerates fracture healing via modulating miR-701-3p/FGFR3 axis

Emerging evidence highlights the role of the long noncoding RNA (lncRNA) KCNQ1OT1 in fracture healing. Osteoblast proliferation, migration, and survival are pivotal during this process. In this study, we aimed to improve our understanding of the regulatory role of lncRNA KCNQ1OT1 during osteoblast proliferation, migration, and survival. We searched the gene expression omnibus databases and LncBase Experimental V.2 to identify key microRNAs (miRNAs) targets of KCNQ1OT1. MiR-701-3p was selected as a differentially expressed miRNA and RNA immunoprecipitation assays were performed to verify its interaction with KCNQ1OT1. Fibroblast growth factor receptor 3 (FGFR3) was also identified as a target of miR-701-3p. We further identified KCNQ1OT1 as a competing endogenous RNA of miR-701-3p that could influence osteoblast proliferation, migration, and apoptosis in vitro and in vivo. Taken together, our results indicate that the KCNQ1OT1/miR-701-3p/FGFR3 axis is an important regulator of osteoblast proliferation, migration, and apoptosis, and provide a new therapeutic avenue for fracture healing.

Anastomosis for distal gastrectomy in Chinese patients: uncut roux-Y or roux-Y?

Background

An appropriate method of anastomosis is crucial for gastric cancer patients who require gastrojejunal anastomosis. Surgeons have proposed different types of modified gastrojejunostomies in the last two decades. We focused on two types of standard anastomosis, i.e., Uncut Roux-Y and Roux-Y gastrojejunostomies, and compared the differences in immediate postoperative complications between the two types.

Methods

This is a retrospective study on 236 gastric cancer patients who underwent curative distal gastrectomy with gastrojejunal Roux-Y or Uncut Roux-Y anastomosis for six consecutive years. Immediate postoperative complications were compared between the two groups. The authors discussed the causes of the significant complications and their management.

Results

There was no difference in demographics between the two groups (92 Roux-y Versus 144 Uncut Roux-y). The overall complication rate was 20.8% with 1.4% anastomotic leakage in the Uncut Roux-Y group versus 33.7% with 7.6% anastomotic failures in the Roux-Y group (p < 0.05). More abdominal infections occurred in the Roux-Y anastomosis group compared with the Uncut Roux-Y anastomosis group (p < 0.05). Duration of postoperative stay was significantly longer in patients with Roux-y anastomosis group (p < 0.05).

Conclusions

Considering the surgical simplicity and postoperative complications, the Uncut Roux-Y is a better choice for anastomosis in patients with gastric cancer undergoing gastrojejunostomy. A well-designed large cohort in a multi-centre randomized controlled trial is necessary to support these findings and compare other aspects.

Circulating Exosomal miR-20b-5p Inhibition Restores Wnt9b Signaling and Reverses Diabetes-Associated Impaired Wound Healing

At present, developing therapeutic strategies to improve wound healing in individuals with diabetes remains challenging. Exosomes represent a promising nanomaterial from which microRNAs (miRNAs) can be isolated. These miRNAs have the potential to exert therapeutic effects, and thus, determining the potential therapeutic contributions of specific miRNAs circulating in exosomes is of great importance. In the present study, circulating exosomal miRNAs are identified in diabetic patients and assessed for their roles in the context of diabetic wound healing. A significant upregulation of miR-20b-5p is observed in exosomes isolated from patients with type 2 diabetes mellitus (T2DM), and this miRNA is able to suppress human umbilical vein endothelial cell angiogenesis via regulation of Wnt9b/β-catenin signaling. It is found that the application of either miR-20b-5p or diabetic exosomes to wound sites is sufficient to slow wound healing and angiogenesis. In diabetic mice, it is found that knocking out miR-20b-5p significantly enhances wound healing and promotes wound angiogenesis. Together, these findings thus provide strong evidence that miR-20b-5p is highly enriched in exosomes from patients with T2DM and can be transferred to cells of the vascular endothelium, where it targets Wnt9b signaling to negatively regulate cell functionality and angiogenesis.

Sarcodon aspratus polysaccharides ameliorated obesity-induced metabolic disorders and modulated gut microbiota dysbiosis in mice fed a high-fat diet

The polysaccharides isolated from the fruit body of S. aspratus (SATPs) might be a potential health supplement or prebiotic in the prevention of obesity and associated metabolic disorders.