Sulfur dioxide induces vascular relaxation through PI3K/Akt/eNOS and NO/cGMP signaling pathways in rats

Sulfur dioxide (SO₂) is a common exogenous atmospheric pollutant. Studies have shown that SO₂ can cause vasodilation as a gas signaling molecule, but the specific signaling pathways are not well understood. This study aimed to explore the underlying mechanism behind the effects of SO₂ on vasodilation of isolated rat aorta. The results showed that when the dose of SO₂ was 30 μM, the vasodilation of endothelium-intact rings was partially suppressed by LY294002 and N^G-nitro-l-arginine methyl ester, and the protein levels of phosphoinositide 3-kinase (PI3K), p-Akt, and p-endothelial nitric oxide synthase (p-eNOS) were significantly increased. When the dose of SO₂ was 300 μM or 1500 μM, the vasodilation of endothelium-denuded rings did not change after application of the inhibitor, but the protein levels of PI3K, p-Akt, and p-eNOS were significantly decreased, and the activity of NOS and the level of nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) were significantly increased. We speculate that the mechanism of SO₂-induced vasodilatation likely involved the endothelial PI3K/Akt/eNOS and NO/cGMP signal pathways. In addition, at the concentration of 1500 μM, SO₂ markedly increased the level of caspase-3 and caspase-9. The results suggest that high concentrations of SO₂ may cause damage to blood vessels. This study will help to further inform the etiologies of SO₂-related cardiovascular disease.

Identification of a potential target for treatment of squamous cell carcinoma of the tongue: follistatin

Squamous cell carcinoma (SCC) of the tongue is the most common oral cancer and is prone to develop regional lymph nodes and distant metastases. Reliable and stable therapeutic targets can improve the curative effect and reduce toxic side effects caused by traditional treatments such as surgery, radiotherapy, and chemotherapy. We have analysed three sets of series of functional gene expression of SCC of the tongue from gene expression omnibus (GEO) datasets, and 154 common differentially expressed genes (DEG) between SCC of the tongue and the corresponding normal tissues were screened. Further bioinformatics research that was based on the data from the Cancer genome atlas, Gene ontology, and the Kyoto encyclopaedia of genes and genomes indicated that the increased expression of follistatin might be correlated with a poor prognosis in these patients. By assay of colony formation, reverse transcription polymerase chain reaction (RT-PCR), western blotting, immunohistochemical staining, and lentivirus transfection, we confirmed that downregulation of follistatin inhibited the proliferation of SCC cells in the tongue.

Metformin plus megestrol acetate compared with megestrol acetate alone as fertility-sparing treatment in patients with atypical endometrial hyperplasia and well-differentiated endometrial cancer: a randomised controlled trial

OBJECTIVE

To assess the efficacy of metformin in megestrol acetate (MA)-based fertility-sparing treatment for patients with atypical endometrial hyperplasia (AEH) and endometrioid endometrial cancer (EEC).

DESIGN

A randomised, single-centre, open-label, controlled trial conducted between October 2013 and December 2017.

SETTING

Shanghai OBGYN Hospital of Fudan University, China.

POPULATION

A total of 150 patients (18-45 years old) with primary AEH or well-differentiated EEC were randomised into an MA group (n = 74) and an MA plus metformin group (n = 76).

METHODS

Patients with AEH or EEC were firstly stratified, then randomised to receive MA (160 mg orally, daily) or MA (160 mg orally, daily) plus metformin (500 mg orally, three times a day).

MAIN OUTCOMES AND MEASURES

The primary efficacy parameter was the cumulate complete response (CR) rate within 16 weeks of treatment (16w-CR rate); the secondary efficacy parameters were 30w-CR rate and adverse events.

RESULTS

The 16w-CR rate was higher in the metformin plus MA group than in the MA-only group (34.3 versus 20.7%, odds ratio [OR] 2.0, 95% confidence interval [CI] 0.89-4.51, P = 0.09) but the difference was more significant in 102 AEH patients (39.6 versus 20.4%, OR 2.56, 95% CI 1.06-6.21, P = 0.04). This effect of metformin was also significant in non-obese (51.4 versus 24.3%, OR 3.28, 95% CI 1.22-8.84, P = 0.02) and insulin-sensitive (54.8 versus 28.6%, OR 3.04, 95% CI 1.03-8.97, P = 0.04) subgroups of AEH women. No significant result was found in secondary endpoints.

CONCLUSION

As a fertility-sparing treatment, metformin plus MA was associated with a higher early CR rate compared with MA alone in AEH patients.

TWEETABLE ABSTRACT

For AEH patients, metformin plus MA might be a better fertility-sparing treatment to achieve a higher early CR rate compared with MA alone.

Notch signaling is involved in regulation of LPS-induced macrophage apoptosis through JNK/NF-kB signaling pathway

Notch signaling plays a critical role in the development and function of macrophages. The aim of the present study was to investigate the relationship between Notch signaling pathway and macrophage apoptosis after LPS stimulation. In RAW 264.7 cells, the mRNA expression of Jagged1, Hes1, Hes 5 and GM-CSF, and protein expression of NICD1 and GM-CSF were increased after LPS stimulation. Inhibition of Notch signaling by γ-secretase inhibitor DAPT and the suppression of Notch1 expression using siRNA both significantly prevented LPS induced activation of JNK and NF-kB, and simultaneously the expression of GM-CSF was also down regulated significantly. JNK inhibitor SP600125 was used to block the phosphorylation of JNK signaling, Western blot results showed that the activation of NF-kB was blocked and expression of GM-CSF was down-regulated. Finally, flow cytometry analyses showed that the Notch signaling was involved in the regulation of macrophage apoptosis after LPS stimulation. Our study showed that the Notch signaling pathway was activated and involved in the regulation of macrophage apoptosis after LPS stimulation through JNK/ NF-kB signaling regulated GM-CSF expression.

Epithelial Wnt10a Is Essential for Tooth Root Furcation Morphogenesis

WNT10A (Wingless-type MMTV integration site family, member 10A) plays a crucial role in tooth development, and patients with biallelic WNT10A mutation and mice lacking Wnt10a show taurodontism. However, whether epithelial or mesenchymal WNT10A controls the initiation of the root furcation formation remains unclear, and the functional significance of WNT10A in regulating root morphogenesis has not been clarified. Here, we investigated how Wnt10a affects tooth root development by generating different tissue-specific Wnt10a conditional knockout mice. Wnt10a knockout in the whole tissue (EIIa-Cre;Wnt10a^flox/flox) and in dental epithelium (K14-Cre;Wnt10a^flox/flox) led to an absence of or apically located root furcation in molars of mice, a phenotype that resembled taurodontism. An RNAscope analysis showed that the dynamic epithelial and mesenchymal Wnt10a expression pattern occurred during root development. Immunofluorescent staining of E-cadherin and EdU revealed decreased epithelial cell proliferation at the cervical region of the molar in K14-Cre;Wnt10a^flox/flox mice at postnatal day 0 (PN0), just before the initiation of root morphogenesis. Interestingly, we found increased pulpal mesenchymal cell proliferation in the presumptive root furcating region of the molar in K14-Cre;Wnt10a^flox/flox mice at PN4 and PN7. RNA-seq indicated that among the Wnt ligands with high endogenous expression levels in molars, Wnt4 was increased after epithelial knockout of Wnt10a. The RNAscope assay confirmed that the expression of Wnt4 and Axin2 in the dental papilla of the presumptive root furcating region, where dental pulp overgrowth occurred, was increased in K14-Cre;Wnt10a^flox/flox molars. Furthermore, after suppression of the elevated Wnt4 level in K14-Cre;Wnt10a^flox/flox molars by Wnt4 shRNA adenovirus and kidney capsule grafts, the root furcation defect was partially rescued. Taken together, our study provides the first in vivo evidence that epithelial Wnt10a guides root furcation formation and plays a crucial role in controlling the organized proliferation of adjacent mesenchymal cells by regulating proper Wnt4 expression during root furcation morphogenesis.

Antidepressant Drugs Correct the Imbalance Between proBDNF/p75NTR/Sortilin and Mature BDNF/TrkB in the Brain of Mice with Chronic Stress

Depression is a worldwide problem with a great social and economic burden in many countries. In our previous research, we found that the expression of proBDNF/p75NTR/sortilin is upregulated in patients with major depressive disorder. In addition, the treatment of proBDNF antibodies reversed both the depressive behaviors and the reduced BDNF mRNA detected in our rodent chronic stress models. Antidepressant drugs are usually only effective in a subpopulation of patients with major depression with a delayed time window of 2-4 weeks to exert their efficacy. The mechanism underlying such delayed response is not known. In this study, we hypothesize that antidepressant drugs exert their therapeutic effect by modulating proBDNF/p75NTR and mature BDNF/TrkB signaling pathways. To test the hypothesis, C57 mice were randomly divided into normal control, chronic unpredictable mild stress (CUMS), vehicle (VEH), fluoxetine (FLU), and clozapine (CLO) groups. Behavioral tests (sucrose preference, open field, and tail suspension tests) were performed before and after 4 weeks of CUMS. The gene and protein expression of proBDNF, the neurotrophin receptor (p75NTR), sortilin, and TrkB in the cortex and hippocampus were examined. At the protein level, CUMS induced a significant increase in proBDNF, p75NTR, and sortilin production while the TrkB protein level was found to be lower in the cortex and hippocampus compared with the control group. Consistently, at the mRNA level, p75NTR expression increased with reduced BDNF/TrkB mRNA in both cortex and hippocampus, while sortilin increased only in the hippocampus after CUMS. FLU and CLO treatments of CUMS mice reversed all protein and mRNA expression of the biomarkers in both cortex and hippocampus, except for sortilin mRNA in the cortex and proBDNF in the hippocampus, respectively. This study further confirms that the imbalance between proBDNF/p75NTR/sortilin and mBDNF/TrkB production is important in the pathogenesis of depression. It is likely that antidepressant FLU and antipsychotic CLO exert their antidepressant-like effect correcting the imbalance between proBDNF/p75NTR/sortilin and mBDNF/TrkB.

miR-126 suppresses neuronal apoptosis in rats after cardiopulmonary resuscitation via regulating p38MAPK

In this study, we aimed to evaluate the effect of microRNA-126 (miR-126) on neuronal apoptosis in cardiopulmonary resuscitation rats and to explore the related molecular mechanism. The expression of miR-126 in brain tissues of rats after cardiopulmonary resuscitation was measured by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR). The basic parameters of cardiopulmonary resuscitation were recorded by miR-126 mimic injection in rats after cardiopulmonary resuscitation. Hematoxylin-eosin staining was used to observe the pathological changes of hippocampus. Immunohistochemistry was used to observe the expression of p38 and caspase-3 protein. Furthermore, the expression of p38 mitogen-activated protein kinase (p38MAPK), Jun N-terminal kinase (JNK), and extracellular signal-regulated kinase 1/2 (ERK1/2) in rat hippocampus was detected by RT-qPCR and Western blot. In order to confirm whether miR-126 takes part in the p38MAPK pathway in the hippocampus of rats after cardiopulmonary resuscitation, the p38MAPK pathway inhibitor (SB203580) and activator (anisomycin) were added. The results showed overexpression of miR-126 could significantly increase the neurological function score and improve the pathological morphology of hippocampus in rats after cardiopulmonary resuscitation. miR-126 overexpression also could reduce the neuronal apoptosis, p38, and caspase-3 expression in the hippocampus. Moreover, the p38MAPK and JNK expression was downregulated and ERK1/2 expression was upregulated after miR-126 mimic injection (p < 0.05). The results of inhibition of p38MAPK pathway were consistent with those of overexpression of miR-126 (p > 0.05). This study indicated miR-126 could significantly reduce neuronal apoptosis of hippocampus in rats after cardiopulmonary resuscitation, which might be involved in the regulation of p38MAPK pathway.

Preliminary report of the use of a microvascular coupling device for arterial anastomoses in oral and maxillofacial reconstruction

Our aim was to record our preliminary use of a microvascular coupler for arterial anastomoses with free flap transfer in the reconstruction of oral and maxillofacial defects in 45 patients with defects that were repaired with anterolateral thigh, fibular, and radial forearm flaps. The microvascular coupler was used for both the venous and the arterial anastomoses. The site of the defect, type of flap, recipient artery, duration of operating time for the anastomosis, size of coupler, and survival of the flap were recorded and analysed. A total of 45 consecutive patients had microsurgical reconstructions in the head and neck, including 16 radial forearm, 18 fibular, and 11 anterolateral thigh free flaps. The sizes of coupler required ranged from 1.5-2.5 mm, with most flaps (n = 30) requiring a 2.0 mm coupler. The mean (SD) operating time for arterial anastomoses was 7 (2) mins. One arterial crisis occurred during an operation, and required a sutured anastomosis instead. There were no complications related to the technical performance of the coupler. The coupler is reliable for arterial anastomoses of free tissue transfers in reconstructions of the head and neck. With proper selection of vessels and enough experience in using the microvascular coupler, it may be used in an expeditious, safe, and reliable fashion with minimal morbidity. Though not common, the use of the coupler for arterial anastomoses saves a lot of time, and is a viable alternative to a sutured anastomosis.

[The value of muscle biopsy in rhabdomyolysis]

Objective: To analyze the diagnostic value of skeletal muscle biopsy in patients with rhabdomyolysis. Methods: Clinical and pathological data of 26 patients with rhabdomyolysis from January 2002 to December 2018 undergoing muscle biopsy were collected. Results: Eighteen males and 8 females were finally recruited with median age of 6-73 (37.3±19.6) years. The average time from onset to biopsy was 44 days (median course was 30 days). All patients had acute manifestations with muscle pain and/or weakness. Serum creatine kinase was between 1 648-92 660 U/L. Muscle biopsies showed nonspecific changes in 12 cases (a few with type 2 muscle fiber atrophy, slight deposition of lipid droplets), 10 cases with necrotizing myopathy (muscle fiber necrosis and regeneration). Toxic neurogenic damages were seen in 2 cases (type 1 and type 2 angular atrophic muscle fibers with group change), lipid storage disease in 1 case (lipid droplets deposit significantly) and idiopathic inflammatory myopathy in 1 case (muscle fiber necrosis and regeneration, with lymphocyte infiltration). The etiology of non-specific pathological changes included short-term strenuous exercise in 6 patients, poisoning in two, chronic kidney disease in one, viral infection in one, hypothyroidism in one and unknown reason in one. As to patients with necrotizing myopathy, seven were poisoning or drug-related, one with hyperthyroidism, two with unknown reason. Conclusions: Among the numerous causes of rhabdomyolysis, exercise usually links nonspecific skeletal muscle changes and poisoning or drug-related disorders are commonly associated with necrotic myopathy. Rhabdomyolysis induced by primary myopathy is rare.

Oral vaccination with the porcine circovirus type 2 (PCV-2) capsid protein expressed by Lactococcus lactis induces a specific immune response against PCV-2 in mice

AIMS

Porcine circovirus type 2 (PCV2) can cause postweaning, multisystemic wasting syndrome in pigs, which leads to enormous losses in the swine industry worldwide. Here, a genetically engineered Lactococcus strain expressing the main protective antigen of PCV2, the Cap protein, was developed to act against PCV2 infection as an oral vaccine.

METHODS AND RESULTS

Expression of the Cap protein was confirmed via western blot, ELISA and fluorescence microscopy. Over 90% of the recombinant pAMJ399-Cap/MG1363 survived a simulated gastrointestinal transit. It also survived the murine intestinal tract for at least 11 days. Then, the safety and immunogenicity of pAMJ399-Cap/MG1363 in orally immunized mice was evaluated. The levels of the sIgA, IgG and cytokines (IL-4 and IFN-γ) obtained from the mice immunized with pAMJ399-Cap/MG1363 were significantly higher than those in the control groups.

CONCLUSIONS

pAMJ399-Cap/MG1363 can survive in the gastrointestinal transit and effectively induce mucosal, cellular and humoral immune response against PCV2 infection via oral administration.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study demonstrates the potential of the genetically engineered Lactococcus lactis as a candidate for an oral vaccine against PCV2.

[Association between edentulism and cognition among people aged 50 and over]

Objective: To investigate the association between edentulism and cognition in people aged 50 and over in China. Methods: Cross-sectional data was collected from the first wave of World Health Organization Study on global AGEing and adult health in China, among people aged 50 and over in China. A comprehensive cognitive test was used to assess cognitive functions, including verbal recall (VR), verbal fluency (VF), forward digit span (FDS) and backward digit span (BDS) among the subjects. Association between edentulism and cognition was examined by a two-level (individual level and community level) linear model. Results: A total of 12 843 individuals aged 50 years and over were included for analysis, with an average age of (63.0±9.3) years. The overall prevalence of edentulism was 11.0%. The edentulous adults had lower mean scores of VR (4.55), VF (10.88), FDS (6.25), BDS (2.96) and overall cognition (49.15) (P<0.001). Edentulism was negatively associated with VR (β=-0.216, 95%CI: -0.370 - -0.062), FDS (β=-0.186, 95%CI: -0.293 - -0.078) and overall cognition (β=-1.703, 95%CI: -3.025 - -0.381) after adjusted for age, sex, residence, education level, marital status, household income, co-morbidity of chronic conditions, BMI, smoking and drinking alcohol. Conclusion: Edentulism was related with lower cognition level in people aged 50 and over in China.

Long-term decomposed straw return positively affects the soil microbial community

AIMS

In order to understand the response of soil microbial communities to the long-term of decomposed straw return, the modifications of soil microbial community structure and composition induced by more than 10 years of fresh and decomposed straw return was investigated and the key environmental factors were analysed.

METHODS AND RESULTS

Phospholipid fatty acid analysis and high-through sequencing technique were applied to analyse the structure and composition of the soil microbial communities. Compared with fresh straw, returning decomposed straw increased the relative abundance of bacteria and fungi by 1·9 and 7·7% at a rate of ~3750 kg ha^-1 , and increased by 23·1 and 5·7%, at a rate of ~7500 kg ha^-1 respectively. The relative abundance of the bacteria related to soil nitrification increased, but the ones related to soil denitrification decreased with decomposed straw return, which led to higher total nitrogen contents in soils. Moreover, returning decomposed straw reduced pathogenic fungal populations (genus of Alternara), which had significantly positive correlation with soil electric conductivity. It indicated that the long-term of decomposed straw return might have lower risk of soil-borne disease mainly for the reasonable soil salinity.

CONCLUSIONS

Long-term of decomposed straw return could provide suitable nutrient and salinity for healthier development of soil microbial community, both in abundance and structure, compared with fresh straw return.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results of the study helps to better understand how the microbial community modifications induced by decomposed straw return benefit on soil health. The obtained key factors impacting soil microbial community variations is meaningful in soil health management under conditions of straw return.

The Chinese National Twin Registry: a 'gold mine' for scientific research

The Chinese National Twin Registry (CNTR) currently includes data from 61 566 twin pair from 11 provinces or cities in China. Of these, 31 705, 15 060 and 13 531 pairs are monozygotic, same-sex dizygotic and opposite-sex dizygotic pairs, respectively, determined by opposite sex or intrapair similarity. Since its establishment in 2001, the CNTR has provided an important resource for analysing genetic and environmental influences on chronic diseases especially cardiovascular diseases. Recently, the CNTR has focused on collecting biologic specimens from disease-concordant or disease-discordant twin pairs or from twin pairs reared apart. More than 8000 pairs of these twins have been registered, and blood samples have been collected from more than 1500 pairs. In this review, we summarize the main findings from univariate and multivariate genetic effects analyses, gene-environment interaction studies, omics studies exploring DNA methylation and metabolomic markers associated with phenotypes. There remains further scope for CNTR research and data mining. The plan for future development of the CNTR is described. The CNTR welcomes worldwide collaboration.

[Interpretation for the group standards in technical specification of long-term follow-up for end point in large population-based cohort study]

Long-term follow-up for end point is an extremely important and arduous task in large population-based cohort studies, which is also the key to the success of large cohort studies. Thus, the fundamental question of the achievements above is how to construct a large population- based cohort in a standardized way. The Chinese Preventive Medicine Association coordinated experienced researchers from Zhejiang Provincial Center for Disease Control and Prevention and other professional institutes to write up the group standard entitled Technical specification of long-term follow-up for end point in large population-based cohort study (T/CPMA 002-2019). The standard is drafted with principles of emphasizing the scientific, normative, applicability, and feasible nature. This group standard recommended the follow-up target population, time, content, methods, quality control, and indicators assessment. The standard aims to guide the large population-based cohorts that have been or intended to be established in China, including national cohorts, regional population cohorts, and special population cohorts, hence, to improve domestic scientific research level and the international influence, and to support decision-making and practice of disease prevention and control.

[Interpretation for the group standards in technical specification of management for field survey in large population-based cohort study]

Large population-based cohort study is an important resource for population disease prevention and control, the results of which provide scientific basis for individualized treatment and precise prevention, and it is also the key strategic content of precision medicine. The Chinese Preventive Medicine Association coordinated experienced researchers from the Chinese Academy of Medical Sciences and other professional institutes to write up the group standard entitled Technical specification of management for field investigation in large population-based cohort study (T/CPMA 001-2019). Based on the research of large population-based cohort study in China and the principle of scientific, normative, applicable, and feasible, the standard proposed six aspects of management requirements including institutional arrangement, personnel composition, equipment, materials, documents and finance, as well as the basic requirements of the on-site investigation, the requirements of each position and the overall quality control requirements, etc.. The standard aims to guide the large population-based cohorts that have been or intended to be established in China, including national cohorts, regional population cohorts, and special population cohorts, hence to improve scientific research level, accelerate scientific research output and provide localization basis for disease prevention and control in China.

Small molecule delivery across a perforated artificial membrane by thermoreversible hydrogel poloxamer 407

Microperforations in the round window membrane have been suggested for enhancing the rate and reliability of drug delivery into the cochlea. Intratympanic injection, the most common delivery method, involves injecting therapy into the middle ear to establish a reservoir from which drug diffuses across the round window membrane into the cochlea. This process is highly variable because (i) the reservoir, if liquid, can lose contact with the membrane and (ii) diffusion across the membrane is intrinsically variable even with a stable reservoir. To address these respective sources of variability, we compared the thermoreversible hydrogel poloxamer 407 (P407) to saline as a drug carrier and studied the effect of membrane microperforations on drug diffusion rate. We used Rhodamine B as a drug proxy to measure permeance across an artificial membrane in a horizontal diffusion cell. We found that permeance of Rhodamine B from a saline reservoir was an order of magnitude higher than that from a P407 reservoir across unperforated membranes. Moreover, permeance increased with total perforation cross-sectional area regardless of number of perforations (p < 0.05 for all saline-based experiments), but the same association was not found with P407. Rather, for a P407 reservoir, only a large perforation increased permeance (p < 0.001), while multiple small perforations did not (p = 0.749). These results confirm that for drug dissolved in saline, multiple small perforations can effectively enhance diffusion. However, for drug dissolved in P407, larger perforations are necessary.