COVID-19 vaccines and adverse events of special interest: A multinational Global Vaccine Data Network (GVDN) cohort study of 99 million vaccinated individuals

BACKGROUND

The Global COVID Vaccine Safety (GCoVS) Project, established in 2021 under the multinational Global Vaccine Data Network™ (GVDN®), facilitates comprehensive assessment of vaccine safety. This study aimed to evaluate the risk of adverse events of special interest (AESI) following COVID-19 vaccination from 10 sites across eight countries.

METHODS

Using a common protocol, this observational cohort study compared observed with expected rates of 13 selected AESI across neurological, haematological, and cardiac outcomes. Expected rates were obtained by participating sites using pre-COVID-19 vaccination healthcare data stratified by age and sex. Observed rates were reported from the same healthcare datasets since COVID-19 vaccination program rollout. AESI occurring up to 42 days following vaccination with mRNA (BNT162b2 and mRNA-1273) and adenovirus-vector (ChAdOx1) vaccines were included in the primary analysis. Risks were assessed using observed versus expected (OE) ratios with 95 % confidence intervals. Prioritised potential safety signals were those with lower bound of the 95 % confidence interval (LBCI) greater than 1.5.

RESULTS

Participants included 99,068,901 vaccinated individuals. In total, 183,559,462 doses of BNT162b2, 36,178,442 doses of mRNA-1273, and 23,093,399 doses of ChAdOx1 were administered across participating sites in the study period. Risk periods following homologous vaccination schedules contributed 23,168,335 person-years of follow-up. OE ratios with LBCI > 1.5 were observed for Guillain-Barré syndrome (2.49, 95 % CI: 2.15, 2.87) and cerebral venous sinus thrombosis (3.23, 95 % CI: 2.51, 4.09) following the first dose of ChAdOx1 vaccine. Acute disseminated encephalomyelitis showed an OE ratio of 3.78 (95 % CI: 1.52, 7.78) following the first dose of mRNA-1273 vaccine. The OE ratios for myocarditis and pericarditis following BNT162b2, mRNA-1273, and ChAdOx1 were significantly increased with LBCIs > 1.5.

CONCLUSION

This multi-country analysis confirmed pre-established safety signals for myocarditis, pericarditis, Guillain-Barré syndrome, and cerebral venous sinus thrombosis. Other potential safety signals that require further investigation were identified.

Clinicopathological features and prognostic factors of salivary gland myoepithelial carcinoma: institutional experience of 42 cases

Myoepithelial carcinoma (MECA) is a rare type of carcinoma for which the clinicopathological features and prognostic factors have not yet been fully clarified. A retrospective study of 42 patients diagnosed with salivary gland MECA was performed, focusing on the clinicopathological features and prognostic factors. Of the 42 patients, 20 died of cancer, 20 lived without tumour, one lived with distant metastasis, and one was lost to follow-up. Overall, 69.0% had tumour recurrence, 16.7% had cervical nodal metastasis, and 21.4% had distant metastasis. The 5-year overall survival rate was 70.2%. Kaplan-Meier analysis revealed that patients with pathological positive lymph nodes (pN+), multiple recurrences of tumour, and higher histological grade had worse overall survival. Multivariate Cox analysis indicated pN+ and higher histological grade to be independent predictors of decreased survival. The 5-year overall survival rate in the pN0 group was 87.5%, while that in the pN+ group was 28.6%. In conclusion, myoepithelial carcinoma can be defined as a tumour with a high incidence of recurrence and poor prognosis, especially in pN+ patients. Pathological positive lymph nodes and histological grade may serve as predictors of survival.

Inhibition mechanism of cordycepin and ergosterol from Cordyceps militaris Link. against xanthine oxidase and cyclooxygenase-2

Cordyceps militaris Link. (C. militaris) is an entomopathogenic fungus that parasitizes the pupa or cocoon of lepidopteran insect larvae, with various bioactive compounds. Cordycepin and ergosterol are the two active components in C. militaris. This study aimed to evaluate the inhibitory activity of cordycepin and ergosterol against xanthine oxidase (XO) and cyclooxygenase-2 (COX-2), as well as investigate the inhibition mechanism. Cordycepin could better inhibit XO (IC50 = 0.014 mg/mL) and COX-2 (IC50 = 0.055 mg/mL) than ergosterol. Additionally, surface hydrophobicity and circular dichroism (CD) spectra results confirmed the conformational changes in enzymes induced by cordycepin and ergosterol. Finally, cordycepin and ergosterol significantly decreased uric acid (UA) and inflammatory factors to normal level in mice with gouty nephropathy (GN). This study could provide theoretical evidence for utilization of C. militaris in hyperuricemia-management functional foods.

Association between lactate metabolism‑related molecules and venous thromboembolism: A study based on bioinformatics and an in vitro model

Venous thromboembolism (VTE) is characterized by a high recurrence rate and adverse consequences, including high mortality. Damage to vascular endothelial cells (VECs) serves a key role in VTE and lactate (LA) metabolism is associated with VEC damage. However, the pathogenesis of VTE and the role of lactate metabolism-related molecules (LMRMs) remain unclear. Based on the GSE48000 dataset, the present study identified differentially expressed (DE-)LMRMs between healthy individuals and those with VTE. Thereafter, LMRMs were used to establish four machine learning models, namely, the random forest, support vector machine and generalized linear model (GLM) and eXtreme gradient boosting. To verify disease prediction efficiency of the models, nomograms, calibration curves, decision curve analyses and external datasets were used. The optimal machine learning model was used to predict genes involved in disease and an in vitro oxygen-glucose deprivation (OGD) model was used to detect the survival rate, LA levels and LMRM expression levels of VECs. A total of four DE-LMRMs, solute carrier family 16 member 1 (SLC16A1), SLC16A7, SLC16A8 and SLC5A12 were obtained and GLM was identified as the best performing model based on its ability to predict differential expression of the embigin, lactate dehydrogenase B, SLC16A1, SLC5A12 and SLC16A8 genes. Additionally, SLC16A1, SLC16A7 and SLC16A8 served key roles in VTE and the OGD model demonstrated a significant decrease in VEC survival rate as well as a significant increase and decrease in intracellular LA and SLC16A1 expression levels in VECs, respectively. Thus, LMRMs may be involved in VTE pathogenesis and be used to build accurate VTE prediction models. Further, it was hypothesized that the observed increase in intracellular LA levels in VECS was associated with the decrease in SLC16A1 expression. Therefore, SLC16A1 expression may be an essential target for VTE treatment.

[Clinical characteristics and surgical outcomes of pediatric epiretinal membranes without specific etiologies]

Objective: To describe clinical characteristics and surgical outcomes of pediatric epiretinal membranes (ERMs) without specific etiologies. Methods: Medical data of a cohort of pediatric patients (≤14 years) who had ERMs without specific etiologies, underwent surgical removal from January 2019 to September 2021, and were followed up for at least 12 months were retrospectively reviewed. Age at presentation, chief complaints, color fundus photographs, optical coherence tomographic images, preoperative and postoperative visual acuities, anatomical changes, and postoperative complications were assessed. Results: There were 14 patients (17 eyes), including 5 females (6 eyes) and 9 males (11 eyes). The mean age at surgery was 6.31±2.91 years, and the follow-up duration was 17.3±9.5 months. Eight patients were found to have low vision in the school physical examination. Fifteen eyes had an appearance of cellophane macular reflex on fundus images. On optical coherence tomographic images, 10 eyes had"taco"folds, and 7 eyes had"ripple"folds. Five eyes had ellipsoid zone disruptions, while 12 eyes had ellipsoid zone integrity. The preoperative and postoperative best-corrected visual acuities in logMAR were 0.532±0.302 and 0.340±0.298. One patient suffered traumatic cataract and secondary retinal detachment postoperatively, and after further vitrectomy, the retina became attached. Conclusion: Pediatric ERMs without specific etiologies were mostly found in school-age children with cellophane macular reflex and"taco"folds. Vitrectomy may result in both potential visual acuity and macular anatomical improvements.

Fermented rape pollen powder can alleviate benign prostatic hyperplasia in rats by reducing hormone content and changing gut microbiota

Benign prostatic hyperplasia (BPH) can cause urethral compression, bladder stone formation, and renal function damage, which may endanger the life of patients. Therefore, we aimed to develop plant-based preparations for BPH treatment with no side effects. In this study, the Lactiplantibacillus plantarum 322Hp, Lactobacillus acidophilus 322Ha, and Limosilactobacillus reuteri 322Hr were used to ferment rape pollen. The fermented rape pollen was subsequently converted into fermented rape pollen powder (FRPP) through vacuum freeze-drying technology. After fermenting and drying, the bioactive substances and antioxidant capacity of FRPP were significantly higher than those of unfermented rapeseed pollen, and FRPP had a longer storage duration, which can be stored for over one year. To investigate the therapeutic effect of FRPP on BPH, a BPH rat model was established by hypodermic injection of testosterone propionate. The BPH rats were treated differently, with the model group receiving normal saline, the positive control group receiving finasteride, and the low, medium, and high dose FRPP group receiving FRPP at doses of 0.14 g/kg/d, 0.28 g/kg/d, and 0.56 g/kg/d, respectively. The results indicate that medium dose FRPP reduced the levels of hormone such as testosterone, dihydrotestosterone, and oestradiol in rats with BPH by about 32%, thus bringing the prostate tissue of BPH rats closer to normal. More importantly, medium dose FRPP treatment had a significant effect on the composition of gut microbiota in rats with BPH, increasing the levels of beneficial genera (such as Coprococcus and Jeotgalicoccus), and decreasing the levels of harmful pathogens (such as Turicibacter and Clostridiaceae_Clostridium) in the gut. This study showed that medium dose FRPP reduced the hormone level and regulated the unbalanced gut microbiota in BPH rats, thereby alleviating BPH.

Gut Microbiota-Derived D-Tagatose from EGCG Attenuates Radiation-Induced Intestinal Injury

PURPOSE/OBJECTIVE(S)

As a rapidly self-renewing tissue, the small intestine is particularly sensitive to ionizing radiation, which limits the outcomes of radiotherapy against abdominal malignancies, resulting in poor prognosis. The polyphenol (-)-epigallocatechin-3-gallate (EGCG), a major bioactive constituent of green tea, is beneficial in radiation-induced intestinal injury (RIII) alleviation. However, the bioavailability of EGCG in vivo is very low, with only 0.1% to 1.6% being absorbed into the intestine of mice. It is unclear whether gut microbial metabolites mediated by EGCG exert an effect to protect against radiation-induced intestinal injury.

MATERIALS/METHODS

Male C57BL/6J mice were subjected to 13 Gy abdominal irradiation after EGCG gavage, and the severity of intestinal tissue damage was evaluated by HE staining, immunohistochemistry, and TUNEL assays. Fresh fecal samples were collected after the end of gavage, and then fecal sterile fecal filtrate (SFF) was obtained. Stool samples were collected 3 d after irradiation. The gut microbiome was detected by 16S rRNA sequencing, the metabolites were detected by GC‒MS analysis, and then the metabolites were applied to male C57BL/6J mice, observing and evaluating the severity of RIII.

RESULTS

We first explored the effect of oral EGCG delivery on radiation-induced intestinal injury. Our results revealed that EGCG pre-supplementation prolongs survival time, prevents weight loss in mice and mitigates radiation-induced intestinal injury in irradiated mice. Using 16S rRNA gene-based microbiota analysis, we first found that EGCG ameliorated ionizing radiation-induced gut microbiota dysbiosis and enriched short-chain fatty acid (SCFA)-producing bacteria such as Roseburia, Ruminococcus, and Clostridia_UCG-014. In addition, metabolomic profiling analysis showed that the gut microbiota modulated EGCG-induced metabolic reprogramming in colonic tissues, particularly by enhancing galactose metabolism. Notably, EGCG supplementation resulted in the enrichment of the microbiota-derived galactose metabolism metabolite D-tagatose. Furthermore, exogenous treatment with D-tagatose reproduced similar protective effects as EGCG to protect against radiation-induced intestinal injury (RIII). D-tagatose restored the length of villi and improved the number of goblet cells, Ki-67-positive cells and Lgr5+ ISCs, while the number of TUNEL-positive cells in the intestinal tissues decreased significantly. To validate these discoveries, we performed fecal sterile fecal filtrate (SFF) from EGCG-dosed mice to untreated mice before ionizing radiation. SFF from EGCG-dosed mice alleviated the RIII over SFF from control mice superiorly.

CONCLUSION

This study provides the first data indicating that oral EGCG ameliorated radiation-induced intestinal injury (RIII) by regulating the gut microbiota and metabolites. Our findings provide novel insights into D-tagatose derived by gut microbiota from EGCG-mediated remission of RIII.

Probiotic Consortia and their Metabolites Protect Intestine Against Radiation Injury by Improving Intestinal Epithelial Homeostasis

PURPOSE/OBJECTIVE(S)

The intestine is a highly radiosensitive tissue that is susceptible to structural and functional damage due to systemic as well as localized radiation exposure. Unfortunately, no therapeutic agents are available at present to manage radiation-induced intestinal injuries (RIII). Probiotics, especially Lactobacillus or Bifidobacterium, are orally taken as food supplements or microbial drugs by patients with gastrointestinal disorders due to their safety, efficacy, and power to restore the gut microenvironment. Our results demonstrate that probiotic consortia and their metabolites could exert protective roles in the RIII mouse model by restoring the structure of the gut microbiota and regulating redox imbalance. Moreover, the effect of probiotic consortia is better than that of any single probiotic strain.

MATERIALS/METHODS

Male C57BL/6J mice were treated with 13 Gy of whole abdominal irradiation (WAI). Probiotics were administered by gavage before (once a day for 30 days) WAI. The survival and body weight were recorded, while the severity of RIII was evaluated by HE staining, immunohistochemistry (IHC) and TUNEL assay of gut tissues. Meanwhile, stool samples were obtained 3.5 d after irradiation. Gut microbiome were measured by 16S rRNA sequencing, and metabolites were detected by LC-MS analysis. For sterile fecal filtrate (SFF), the supernatants were collected and passed through 70 and 0.2μm filters.

RESULTS

Compared to the control, probiotic consortia (Lactobacillus plantarum, Bifidobacterium longum, Lactobacillus paracasei) treatment significantly increased survival rates by 50% (P<0.05) and improved clinical scores of mice after WAI. HE staining showed that probiotics mitigated RIII, as reflected by the dramatic attenuation of crypt-villus architecture destruction. IHC results showed that probiotic consortia treatment markedly increased the Lgr5+ cells, Paneth cells, and Ki67+ cells (P<0.001) per crypt, indicating that probiotics promoted the proliferation and differentiation of ISCs after WAI. Consistent with the H&E staining, the level of CD4/CD8 was increased by the probiotic consortia compared with that of the control group. The probiotic consortia modulated the structure of the gut microbiota and metabolites in the RIII mouse model. To further investigate the impact of metabolites on RIII, crude probiotic fermentation metabolites were administered to the RIII mouse model. Specifically, mice fed the mixed-metabolite daily for 7 days before IR had significantly more Lgr5+ and Ki67+cells in the SI crypt than mice of control. Moreover, treatment with mixed metabolites resulted in insignificant changes in SOD, MDA, GSH and T-AOC activity compared to the control group in intestinal tissues.

CONCLUSION

In the present study, we demonstrate that probiotic consortia and their metabolites treatment attenuate RIII by modulating the structure and composition of the gut microbiota and regulating redox imbalance.

Phenylacetylglutamine as a novel biomarker of type 2 diabetes with distal symmetric polyneuropathy by metabolomics

PURPOSE

Type 2 diabetes mellitus (T2DM) with distal symmetric polyneuropathy (DSPN) is a disease involving the nervous system caused by metabolic disorder, while the metabolic spectrum and key metabolites remain poorly defined.

METHODS

Plasma samples of 30 healthy controls, 30 T2DM patients, and 60 DSPN patients were subjected to nontargeted metabolomics. Potential biomarkers of DSPN were screened based on univariate and multivariate statistical analyses, ROC curve analysis, and logistic regression. Finally, another 22 patients with T2DM who developed DSPN after follow-up were selected for validation of the new biomarker based on target metabolomics.

RESULTS

Compared with the control group and the T2DM group, 6 metabolites showed differences in the DSPN group (P < 0.05; FDR < 0.1; VIP > 1) and a rising step trend was observed. Among them, phenylacetylglutamine (PAG) and sorbitol displayed an excellent discriminatory ability and associated with disease severity. The verification results demonstrated that when T2DM progressed to DSPN, the phenylacetylglutamine content increased significantly (P = 0.004).

CONCLUSION

The discovered and verified endogenous metabolite PAG may be a novel potential biomarker of DSPN and involved in the disease pathogenesis.

[Clinical study of induction chemotherapy followed by allogeneic hematopoietic stem cell transplantation in the treatment of FLT3-ITD(+) acute myeloid leukemia with normal karyotype]

Objective: To assess the efficacy of induction chemotherapy followed by allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the treatment of FLT3-ITD(+) acute myeloid leukemia (AML) with normal karyotype. Methods: The clinical data of FLT3-ITD(+) AML patients with normal karyotype in the First Affiliated Hospital of Nanjing Medical University from Jan 2018 to March 2021 were retrospectively analyzed. Results: The study included 49 patients with FLT3-ITD(+)AML, 31 males, and 18 females, with a median age of 46 (16-59) years old. All patients received induction chemotherapy, and 24 patients received sequential allo-HSCT (transplantation group) . The median follow-up time was 465 days, the one-year overall survival (OS) from diagnosis was (70.0 ± 7.4) %, and one-year disease-free survival (DFS) was (70.3±7.4) %. The one-year OS was significantly different between the transplantation group and the non-transplantation group [ (85.2 ± 7.9) % vs (52.6 ± 12.3) %, P=0.049]. but one-year DFS [ (84.7 ± 8.1) % vs (55.2 ± 11.9) %, P=0.061] was not. No significance was found in one-year OS between patients with low-frequency and high-frequency FLT3-ITD(+) (P>0.05) . There were 12 patients with high-frequency FLT3-ITD(+) in the transplantation and the non-transplantation groups, respectively. The one-year OS [ (68.8 ± 15.7) % in the transplantation group vs (26.2 ± 15.3) % in the non-transplantation group, P=0.027] and one-year DFS [ (45.5 ± 21.3) % in the transplantation group vs (27.8±15.8) % in the non-transplantation group, P=0.032] were significantly different between the two groups. Conclusion: Induction chemotherapy followed by allo-HSCT can enhance the prognosis of FLT3-ITD(+) patients, particularly those with FLT3-ITD high-frequency mutation.

Random Traffic Flow Simulation of Heavy Vehicles Based on R-Vine Copula Model and Improved Latin Hypercube Sampling Method

The rationality of heavy vehicle models is crucial to the structural safety assessment of bridges. To establish a realistic heavy vehicle traffic flow model, this study proposes a heavy vehicle random traffic flow simulation method that fully considers the vehicle weight correlation based on the measured weigh-in-motion data. First, a probability model of the key parameters in the actual traffic flow is established. Then, a random traffic flow simulation of heavy vehicles is realized using the R-vine Copula model and improved Latin hypercube sampling (LHS) method. Finally, the load effect is calculated using a calculation example to explore the necessity of considering the vehicle weight correlation. The results indicate that the vehicle weight of each model is significantly correlated. Compared to the Monte Carlo method, the improved LHS method better considers the correlation between high-dimensional variables. Furthermore, considering the vehicle weight correlation using the R-vine Copula model, the random traffic flow generated by the Monte Carlo sampling method ignores the correlation between parameters, leading to a weaker load effect. Therefore, the improved LHS method is preferred.

Meta-analysis of InterTan, PFNA and PFNA-II internal fixation for the treatment of unstable intertrochanteric fractures in elderly individuals

Elderly individuals are often affected by osteoporosis and have poor stability after fracture reduction. Moreover, there is still controversy regarding the clinical effects of the treatment for unstable intertrochanteric fractures in the elderly. The Cochrane, Embase, PubMed, and other databases were searched, and a meta-analysis of the literature on the treatment of unstable intertrochanteric fractures of the elderly with InterTan, PFNA, and PFNA-II was conducted. Seven studies were screened, with a total of 1236 patients. Our meta-analysis results show that InterTan is not significantly different from PFNA in terms of operation and fluoroscopy times, but it takes longer than PFNA-II. In terms of postoperative screw cut, pain, femoral shaft fracture, and secondary operations, InterTan is superior to PFNA and PFNA-II. Conversely, in terms of intraoperative blood loss, hospital stay, and postoperative Harris score, there is no significant difference between InterTan and PFNA and PFNA-II. Compared to PFNA and PFNA-II, InterTan internal fixation has advantages in the treatment of unstable intertrochanteric fractures in elderly individuals in terms of screw cutting, femoral shaft fractures, and secondary operations. However, InterTan operation and fluoroscopy times take longer than PFNA and PFNA-II.

Kruppel-like Factors 3 Regulates Migration and Invasion of Gastric Cancer Cells Through NF-κB Pathway

Context

The poorly understood regulatory mechanisms impede gastric cancer therapy. Kruppel-like factors (KLFs) are associated with the development of various tumors, The studies on the role of the KLF transcription factor 13 (KLF13) in gastric cancer progression haven't been studied.

Objective

The current study aimed to investigate the role of KLF13 in the migration and invasion of gastric cancer and the regulatory mechanism of KLF13 in gastric cancer progression.

Design

The research team performed a laboratory study.

Setting

The study took place at the Zengcheng District People's Hospital of Guangzhou in Zengcheng, China.

Participants

In addition to using normal gastric cells, GES1, and seven gastric cancer cell lines, the research team compared the fresh, gastric cancer tissues (T) and paired, adjacent, noncancerous gastric tissues (ANT) from eight patients undergoing surgical resection at the hospital. The research team also downloaded the data for 33 gastric cancer tissues and adjacent, normal gastric tissues from the Cancer Genome Atlas' TCGA database.

Intervention

The research team used: (1) short hairpin RNAs (shRNAs) to knock down KLF13, (2) wound healing and transwell invasion analyses to determine the effects of KLF13 on the migration and invasion of gastric cancer, and (3) a Luciferase reporter assay to determine the effects of KLF13 on nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activity.

Results

KLF13 was upregulated in gastric cancer cells and tissues, and the patients with a high KLF13 expression had poor outcome. Downregulation of KLF13 significantly inhibited the migration and invasion of gastric cancer cells. Mechanistically, downregulation of KLF13 significantly inhibited NF-κB activity, and its targets such as: (1) snail family transcriptional repressor 1 (SNAI1 or Snail), (2) snail family transcriptional repressor 2 (SNAI2 or Slug), (3) zinc finger e-box binding homeobox 1 (ZEB1), (4) Smad interacting protein 1 (Sip1), (5) twist family basic helix-loop-helix (BHLH) transcription factor (Twist), (6) matrix metallopeptidase 2 (MMP2), and (7) MMP9. Tumor necrosis factor alpha (TNF-α) can activate NF-κB. Treating with TNF-α can reverse the effects of KLF13 downregulation on migration and invasion, confirming that KLF13 promotes the migration and invasion of gastric cancer cells through activating the NF-κB pathway.

Conclusions

KLF13 promoted the migration and invasion of gastric cancer cells through activating the NF-κB pathway, providing a new target for gastric cancer therapy.

Association between sarcopenia and prediabetes among non-elderly US adults

AIM

To explore the specific association between sarcopenia and prediabetes based on large population samples.

METHODS

A total of 16,116 U.S. adults aged 20-59 with dual energy X-ray absorptiometry (DXA) was identified from the National Health and Nutrition Examination Surveys (NHANES). Sarcopenia was defined according to appendicular skeletal muscle mass (ASM) adjusted for body mass index (BMI). Multivariable binary logistic regression models were used to ascertain odds ratios (ORs) for developing prediabetes. Stratified analyses were also performed.

RESULTS

Prevalence of prediabetes was higher in the sarcopenia group (n = 1055) compared with the non-sarcopenia group (n = 15,061) (45.50% vs 28.74%, P < 0.001). Sarcopenia was strongly associated with an increased risk of prediabetes after full adjustment (OR = 1.21, 95CI%: 1.05, 1.39, P = 0.009). In the stratified analysis, this association remained significant independent of obesity, triglycerides, and low-density lipoprotein cholesterol levels. When sarcopenia subjects combined with obesity especially central obesity, the risk of prediabetes was the highest (OR = 2.63, 95CI%: 2.22, 3.11, P < 0.001). Furthermore, a greater proportion of any of impaired glucose tolerance (IGT) individuals was observed in the sarcopenia group compared to the non-sarcopenia group among prediabetes population (41.72% vs 24.06%, P < 0.001).

CONCLUSIONS

Sarcopenia was positively associated with prevalent prediabetes especially IGT in the non-elderly. Moreover, synergistic interactions between the sarcopenia and obesity could greatly increase the risk of prediabetes.

METTL21C mediates lysine trimethylation of IGF2BP1 to regulate chicken myoblast proliferation

1. Methyltransferase-like 21C (METTL21C) and insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) play important roles in the proliferation of chicken myoblasts. However, it remains unclear whether there is protein-protein interaction between METTL21C and IGF2BP1 to regulate proliferation of chicken myoblasts.2. In this study, the Igf2bp1 gene was amplified from cDNA of liver tissue of Lueyang black-bone chicken to construct the overexpression vector HA-Igf2bp1. The HA-Igf2bp1 and Flag-Mettl21c vectors were individually transfected and co-transfected into HEK293T, respectively. Co-immunoprecipitation (Co-IP) assay indicated a protein-protein interaction between METTL21C and IGF2BP1.3. Using the Western blotting and LC-MS/MS, it was found that METTL21C could mediate the lysine methylation modification of IGF2BP1. Furthermore, the His-tagged overexpression vector HA-Igf2bp1-His was constructed, transfected and co-transfected with Flag-Mettl21c into HEK293T. His-tagged IGF2BP1 was purified by nickel ion affinity chromatography. Western blotting revealed that IGF2BP1 was successfully purified, and the trimethylation modification level of co-transfection group was significantly elevated compared with the single-transfection Igf2bp1 group.4. Mettl21c and Igf2bp1 overexpression vectors were transfected and co-transfected into primary chicken myoblasts, respectively. The results of 5-ethynyl-2'-deoxyuridine assay and the expression level of Pax7 and MyoD indicated that overexpression of Igf2bp1 alone inhibited the chicken myoblast proliferation, whereas co-expression of Mettl21c and Igf2bp1 eliminated the inhibitory effects of Igf2bp1, thereby favouring cell proliferation and differentiation.5. The results, for the first time, revealed that METTL21C mediated the lysine trimethylation modification of IGF2BP1 to regulate the proliferation of chicken myoblasts, which provided a new insight into in-depth analysis of the molecular mechanism of METTL21C methylation involved in regulating the growth and development of skeletal muscle in Lueyang black-bone chicken.

Small Molecule-Activated O-GlcNAcase for Spatiotemporal Removal of O-GlcNAc in Live Cells

The nutrient sensor O-linked N-acetylglucosamine (O-GlcNAc) is a post-translational modification found on thousands of nucleocytoplasmic proteins. O-GlcNAc levels in cells dynamically respond to environmental cues in a temporal and spatial manner, leading to altered signal transduction and functional effects. The spatiotemporal regulation of O-GlcNAc levels would accelerate functional interrogation of O-GlcNAc and manipulation of cell behaviors for desired outcomes. Here, we report a strategy for spatiotemporal reduction of O-GlcNAc in live cells by designing an O-GlcNAcase (OGA) fused to an intein triggered by 4-hydroxytamoxifen (4-HT). After rational protein engineering and optimization, we identified an OGA-intein variant whose deglycosidase activity can be triggered in the desired subcellular compartments by 4-HT in a time- and dose-dependent manner. Finally, we demonstrated that 4-HT activation of the OGA-intein fusion can likewise potentiate inhibitory effects in breast cancer cells by virtue of the reduction of O-GlcNAc. The spatiotemporal control of O-GlcNAc through the chemically activatable OGA-intein fusion will facilitate the manipulation and functional understanding of O-GlcNAc in live cells.

Hydrogen sulfide protects against ischemic heart failure by inhibiting RIP1/RIP3/MLKL-mediated necroptosis

The aim of the present study was to explore whether hydrogen sulfide (H2S) protects against ischemic heart failure (HF) by inhibiting the necroptosis pathway. Mice were randomized into Sham, myocardial infarction (MI), MI + propargylglycine (PAG) and MI + sodium hydrosulfide (NaHS) group, respectively. The MI model was induced by ligating the left anterior descending coronary artery. PAG was intraperitoneally administered at a dose of 50 mg/kg/day for 4 weeks, and NaHS at a dose of 4mg/kg/day for the same period. At 4 weeks after MI, the following were observed: A significant decrease in the cardiac function, as evidenced by a decline in ejection fraction (EF) and fractional shortening (FS); an increase in plasma myocardial injury markers, such as creatine kinase-MB (CK-MB) and cardiac troponin I (cTNI); an increase in myocardial collagen content in the heart tissues; and a decrease of H2S level in plasma and heart tissues. Furthermore, the expression levels of necroptosis-related markers such as receptor interacting protein kinase 1 (RIP1), RIP3 and mixed lineage kinase domain-like protein (MLKL) were upregulated after MI. NaHS treatment increased H2S levels in plasma and heart tissues, preserving the cardiac function by increasing EF and FS, decreasing plasma CK-MB and cTNI and reducing collagen content. Additionally, NaHS treatment significantly downregulated the RIP1/RIP3/MLKL pathway. While, PAG treatment aggravated cardiac function by activated the RIP1/RIP3/MLKL pathway. Overall, the present study concluded that H2S protected against ischemic HF by inhibiting RIP1/RIP3/MLKL-mediated necroptosis which could be a potential target treatment for ischemic HF.

[Research progress of persistent hyperplastic primary vitreous with Peters anomaly]

Persistent hyperplastic primary vitreous is a rare congenital ocular developmental malformation caused by the failure of regression of the primary vitreous during the embryonic development period. Peters anomaly is a monogenetic disease of congenital anterior segment dysgenesis. Recent studies have shown that these two diseases may occur concomitantly and be associated with a variety of systemic abnormalities. This review demonstrates the basis of ocular embryonic development, research status of molecular genetics, clinical manifestations, surgical objectives and progress of treatment of persistent hyperplastic primary vitreous with Peters anomaly, in order to provide guidance for clinical practice and research as well as to promote further progression of related gene detection.

Anterior cervical discectomy and fusion with zero-profile versus stand-alone cages for two-level cervical spondylosis: A retrospective cohort study

OBJECTIVE

To assess the mid-long-term clinical and radiological outcomes of zero-profile (ZP) compared with stand-alone (ST) cages for two-level anterior cervical discectomy and fusion (ACDF).

METHODS

We included 77 patients (39 women and 38 men) who underwent two-level ACDF between May 5, 2016, and May 5, 2020, and who were followed up for at least 1 year. The subjects were divided into the ST (n = 38) and ZP (n = 39) group. For the evaluation of functional status, Japanese Orthopedic Association (JOA), Neck Disability Index (NDI), and Visual Analogue Scale (VAS) scores were used. Additionally, radiological outcomes and procedure complications were observed at final follow-up.

RESULTS

Both groups had excellent clinical outcomes at the final follow-up. There were no significant intergroup (ZP vs. ST) differences in the fusion rate (91.02% vs. 90.79%, P > 0.05) and postoperative dysphagia (15.4% vs. 2.6%, P = 0.108). However, the disc height at the final follow-up in the ZP group was higher than that in the ST group (6.86 ± 0.84 vs. 6.17 ± 1.03, P = 0.002). The ZP group accomplished a lower loss of cervical lordosis (18.46 ± 4.78 vs. 16.55 ± 4.36, P = 0.071), but without reaching statistical significance.

CONCLUSION

ACDF with either ZP or ST cages turns out to be a dependable strategy for two-level ACDF in terms of clinical results. However, compared with the ST, the ZP cage may achieve a significantly lower loss of disc height.

Curcumin attenuates vascular calcification via the exosomal miR-92b-3p/KLF4 axis

Vascular calcification (VC) is the most widespread pathological change in diseases of the vascular system. However, we do not have a good understanding of the molecular mechanisms and effective therapeutic approaches for VC. Curcumin (CUR) is a natural polyphenolic compound that has hypolipidemic, anti-inflammatory, and antioxidant effects on the cardiovascular system. Exosomes are known to have extensive miRNAs for intercellular regulation. This study investigated whether CUR attenuates VC by affecting the secretion of exosomal miRNAs. Calcification models were established in vivo and in vitro using vitamin D3 and β-glycerophosphate, respectively. Appropriate therapeutic concentrations of CUR were detected on vascular smooth muscle cells (VSMCs) using a cell counting kit 8. Exosomes were extracted by super speed centrifugation from the supernatant of cultured VSMCs and identified by transmission electron microscopy and particle size analysis. Functional and phenotypic experiments were performed in vitro to verify the effects of CUR and exosomes secreted by VSMCs treated with CUR on calcified VSMCs. Compared with the calcified control group, both CUR and exosomes secreted by VSMCs after CUR intervention attenuated calcification in VSMCs. Real-Time quantitative PCR (RT-qPCR) experiments showed that miR-92b-3p, which is important for alleviating VC, was expressed highly in both VSMCs and exosomes after CUR intervention. The mimic miR-92b-3p significantly decreased the expression of transcription factor KLF4 and osteogenic factor RUNX2 in VSMCs, while the inhibitor miR-92b-3p had the opposite effect. Based on bioinformatics databases and dual luciferase experiments, the prospective target of miR-92b-3p was determined to be KLF4. Both mRNA and protein of RUNX2 were decreased and increased in VSMCs by inhibiting and overexpressing of KLF4, respectively. In addition, in the rat calcification models, CUR attenuated vitamin D3-induced VC by increasing miR-92b-3p expression and decreasing KLF4 expression in the aorta. In conclusion, our study suggests that CUR attenuates vascular calcification via the exosomal miR-92b-3p/KLF4 axis.

Cytocompatibility of pH-sensitive, chitosan-coated Fe3O4 nanoparticles in gynecological cells

Nanoparticles that contact human cells without damaging basic human tissues are becoming more widely used in medicine. Efficient delivery to the intracellular target cell or compartment through the cell membrane must be achieved with minimal cytotoxicity to healthy cells. Fe₃O₄ nanoparticles have been widely used in biomedical research for their magnetic, non-toxic, and biocompatible properties. However, the effects of Fe₃O₄ nanoparticles coated with chitosan (CS) on gynecological cells are unclear. In this study, the Fe₃O₄ nanoparticles were coated with CS to enhance their cytocompatibility and dispersion in water. These CS-Fe₃O₄ nanoparticles were taken up by gynecological cells and did not affect cell viability in vitro. They have greater cytocompatibility in acidic environments than normal Fe₃O₄ nanoparticles and have the potential for drug delivery into gynecological cells.

LncRNA ABHD11-AS1 promotes tumor progression in papillary thyroid carcinoma by regulating EPS15L1/EGFR signaling pathway

OBJECTIVES

lncRNA ABHD11 antisense RNA 1 (ABHD11-AS1) acts as an oncogene involved in papillary thyroid carcinoma (PTC) occurrence and progression. ABHD11-AS1 exerts biologic functions by some miRNAs and proteins to regulate multiple targets. Identification of novel mechanism of ABHD11-AS1 could be helpful in therapeutic targeting for PTC treatment.

METHODS

Differentially expressed lncRNAs were selected from TCGA database. qRT-PCR analysis was applied to examine the expression of ABHD11-AS1 in PTC cell lines and tissues. The relationship of ABHD11-AS1 expression and clinicopathological features was analyzed by Kaplan-Meier analysis. Two PTC cell lines (TPC-1 and KTC-1) were transfected with pcDNA 3.1, pcDNA3.1-ABHD11-AS1, si-NC and si-ABHD11-AS1, respectively, to verify the ABHD11-AS1 oncogene-regulating capacity to promote tumor progression. The cell metastasis and proliferation had been evaluated both in vitro and in vivo.

RESULTS

High expression of ABHD11-AS1 was found in PTC tissues (P < 0.01), which was significantly correlated with lymph node metastasis (P < 0.05). ABHD11-AS1 overexpression noticeably promoted cell proliferation, migration, and invasion capabilities, which were obviously decreased upon ABHD11-AS1 knockdown. ABHD11-AS1 positively regulated EGFR/EPS15L1 pathway, as EGFR, EPS15L1, STAT3, and p-STAT3 were activated.

CONCLUSION

ABHD11-AS1 promotes tumor progression in PTC by regulating EPS15L1/EGFR pathway.

Overexpression of microRNA-145 enhanced docetaxel sensitivity in breast cancer cells via inactivation of protein kinase B gamma-mediated phosphoinositide 3-kinase -protein kinase B pathway

Chemoresistance is a major challenge for the treatment of breast cancer (BC). Previous studies showed that miR-145 level decreases in chemoresistant BC tissues. Nevertheless, the biological function of miR-145 on docetaxel resistance of BC cells remains unclear, which is what our research attempted to clarify. RT-qPCR analyzed miR-145 level, and cell viability and colony formation assays assessed the impact of miR-145 on docetaxel resistance. Molecular mechanisms of miR-145-mediated docetaxel sensitivity were examined by Luciferase reporter assay and Western Blot assessed the function of AKT3 and PI3K/AKT signaling. Our research found that miR-145 expression presented significant downregulation in docetaxel-resistant BC cells. Meanwhile, miR-145 overexpression facilitated the docetaxel sensitivity of BC cells in vivo and in vitro, while the miR-145 inhibitor decreased the sensitivity of BC cells to docetaxel. We also observed that miR-145 inhibited docetaxel resistance mainly via downregulation of the AKT3 expression and further inhibited PI3K/AKT pathway. To conclude, this research provides a novel strategy for improving chemosensitivity through the newly identified miR-145-AKT3/PI3K-AKT signaling pathway in BC.

[Clinicopathological characteristics and differential diagnosis of 6 cases of congenital granular cell tumor]

To provide references for the diagnosis and treatment of congenital granular cell tumor (CGCT), by comprehensive analysis of the clinical data, histopathological and immunohistochemical results. Patients with CGCT were involede, from March 2015 to November 2020, at the Department of Oral and Maxillofacial Surgery of the First Affiliated Hospital of Zhengzhou University. A total of 6 children, aged 3-16 days, 1 male and 5 female, 5 maxillary and 1 mandibular, with maximum tumor diameter of 6-70 mm, were included. The lesions of CGCT were single and connected to the alveolar ridge by a pedicle. The surface of the tumor was covered with a vascular network, and two cases had ulcers on the surface of the tumor. All 6 cases had the tumor removed surgically and there was no recurrence or metastasis in the follow-up visit. Although CGCT is rare, it is a benign tumor and generally does not recur or metastasize after surgery, and has a good prognosis. The prenatal imaging, clinical manifestations after delivery, pathological characteristics and immunohistochemical analyses may provide reference for early diagnosis and treatment of CGCT.

Cingulate circuits are associated with escalation of heroin use and naloxone-induced increases in heroin self-administration

Opioid use disorder (OUD) is defined as a compulsion to seek and take opioids, loss of control over intake and the development of a negative emotional state when access to opioids is denied. Using functional magnetic resonance imaging (fMRI) data in a rat model of OUD, we demonstrate that the escalation of heroin self-administration (SA) and the increased heroin SA following an injection of an opioid receptor antagonist (naloxone) are associated with changes in distinct brain circuits, centered on the cingulate cortex (Cg). Here, SA escalation score was negatively associated with changes in resting state functional connectivity (rsFC) between the Cg and the dorsal striatum. Conversely, increased heroin SA following naloxone injection, was associated with increased connectivity between the Cg and the extended amygdala and hypothalamus. Naloxone-induced increased SA was also positively associated with changes in the amplitude of low frequency fluctuations within the Cg, a measure of spontaneous neuronal activity. Characterizing the distinct brain circuit and behavior changes associated with different facets of addiction increases our understanding of OUD and may provide insight into addiction prevention and treatment.

Preparation and performance study of a reactive polyurethane hot-melt adhesive/CS–Fe3O4 magnetic nanocomposite film/fabric

Magnetic nanoparticles are attracting significant attention for their wide application as biomaterials and magnetic storage materials. As an environmentally friendly adhesive, reactive polyurethane hot-melt adhesive (PUR) is a biocompatible polymer with a wide range of applications. In this paper, chitosan (CS)-surface-modified magnetic Fe₃O₄ nanoparticles were synthesized by the sol–gel method. Surface modification of the Fe₃O₄ nanoparticles with CS enhanced their mechanical properties in PUR. The nanoparticles were characterized by Fourier transform infrared (FTIR) and X-ray diffraction (XRD) analyses, while their surface morphology was elucidated using scanning electron microscopy (SEM) and projection electron microscopy (TEM) techniques. Subsequently, PUR/CS–Fe₃O₄ magnetic nanocomposite films were prepared using an in situ method, wherein different amounts of CS–surface-modified magnetic Fe₃O₄ nanoparticles were doped into the PUR and coated on the films. The thermal, UV resistance and mechanical properties of the PUR/CS–Fe₃O₄ magnetic nanocomposite films were investigated by TGA, UV spectrometer and tensile testing. CS–Fe₃O₄ nanoparticles were successfully prepared using the sol–gel method and CS to modify the surface of the Fe₃O₄ nanoparticles. The results show that the mechanical properties and UV resistance of PUR/CS–Fe₃O₄ magnetic nanocomposites are improved by almost 50%, so the constructed PUR/CS–Fe₃O₄ magnetic nanocomposites have good UV-resistant properties and mechanical properties. The as-synthesized CS–Fe₃O₄ magnetic nanocomposites show great potential for application to mechanical and textile development.

Magnetic nanoparticles are attracting significant attention for their wide application as biomaterials and magnetic storage materials. As an environmentally friendly adhesive, reactive polyurethane hot-melt adhesive is a biocompatible polymer with a range of applications.

Biosynthesis of Novel Naphthoquinone Derivatives in the Commonly-used Chassis Cells Saccharomyces cerevisiae and Escherichia coli

Naphthoquinones harboring 1,4-naphthoquinone pharmacophore are considered as privileged structures in medicinal chemistry. In pharmaceutical industry and fundamental research, polyketide naphthoquinones were widely produced by heterologous expression of polyketide synthases in microbial chassis cells, such as Saccharomyces cerevisiae and Escherichia coli. Nevertheless, these cell factories still remain, to a great degree, black boxes that often exceed engineers’ expectations. In this work, the biotransformation of juglone or 1,4-naphthoquinone was conducted to generate novel derivatives and it was revealed that these two naphthoquinones can indeed be modified by the chassis cells. Seventeen derivatives, including 6 novel compounds, were isolated and their structural characterizations indicated the attachment of certain metabolites of chassis cells to naphthoquinones. Some of these biosynthesized derivatives were reported as potent antimicrobial agents with reduced cytotoxic activities. Additionally, molecular docking as simple and quick in silico approach was performed to screen the biosynthesized compounds for their potential antiviral activity. It was found that compound 11 and 17 showed the most promising binding affinities against Nsp9 of SARS-CoV-2, demonstrating their potential antiviral activities. Overall, this work provides a new approach to generate novel molecules in the commonly used chassis cells, which would expand the chemical diversity for the drug development pipeline. It also reveals a novel insight into the potential of the catalytic power of the most widely used chassis cells.

Stage of colorectal cancer diagnosis for immigrants: a population-based retrospective cohort study in Ontario, Canada

BACKGROUND

Colorectal cancer (CRC) is the second most common cause of cancer death in Canada. Immigrants in Ontario, Canada's most populous province, are known to have lower rates of CRC screening, but differences in stage of CRC diagnosis are not known.

METHODS

We utilized linked administrative databases to compare early (stage I-II) versus late (stage III-IV) stage of CRC diagnosis for immigrants versus long-term residents among patients diagnosed in Ontario between 2012 and 2017 (n = 37,717) and examined the association of immigration-related, sociodemographic, and healthcare-related factors with stage.

RESULTS

Almost 45% of those with CRC were diagnosed at a late stage. Immigrants were slightly more likely to be diagnosed at a late stage than their long-term resident counterparts [Adjusted relative risks (ARRs) 1.06 (95% CI 1.02-1.10)], but after adjusting for age and sex, this difference was no longer significant. In fully adjusted models, we observed a higher likelihood of late-stage diagnosis for people with the fewest co-morbidities (ARR 0.86 [95% CI 0.83-0.89]) and those with no visits to primary care (versus a high level of continuity of care) [ARR 1.07 (95% CI 1.03-1.12)].

CONCLUSION

Immigrants were not more likely to have a late-stage CRC diagnosis after adjusting for relevant factors, but access to primary care and healthcare contact was significantly associated with diagnostic stage.

IMPACT

Attachment to a primary care provider who provides regular preventive care may play a role in more favorable stage at diagnosis for CRC and thus should be a healthcare system priority.

[Analysis of M2 macrophage infiltration and its clinical significance in 44 patients with multiple primary cancers of the head and neck]

Objective: To investigate and analyze the characteristics of M2 macrophage infiltration and the clinical significance in patients with multiple primary cancers (MPCs) of head and neck in order to explore its role in the diagnosis and prognosis for patients with MPCs. Methods: RNA-seq data were downloaded from the Genomic Data Commons data portal (TCGA) and the R software v4.0.3 was used to statistically analyze the differences. A retrospective analysis was conducted by screening the clinical data of 44 patients (17 males and 27 females) with MPCs in head and neck from July 1998 to February 2016 in the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology. Clinical data from a batch of 41 patients (28 males and 13 females) with gingival cancer and without MPCs from August 2013 to December 2015 were collected and analyzed. The number of CD163 positive cells and the expression patterns in immunohistochemically panoramic slices were observed under high magnification. Chi-square test and Spearman correlation analysis were used to compare the difference and correlation between the CD163 positive counts and/or depths of invasion and the number of incidences. The descriptive statistics on the clinical features was performed by SPSS 25.0. Results: TCGA database analysis showed that the infiltration of macrophage in patients with squamous cell carcinoma of head and neck (HNSCC) was increased compared to the para-cancer sites. A total of 142 tissue samples from 44 patients with MPCs were selected in the present single-center retrospective research. The number of CD163-positive cells in MPCs patients [90.9% (40/44)] was significantly increased compared to single gingival cancer patients [61.0%(25/41)] (r=0.353, P=0.001), which was related to the number of occurrence (r=0.368, P=0.001). The ratio of the CD163 counts in primary tumor to the depths of invasion was positively correlated with the number of onsets (r=0.331, P=0.03). In terms of clinical features, the 44 patients with MPCs were mainly female, non-smoking, no alcohol addiction, no systemic history, Tis-T2 stage and N0 stage squamous cell carcinoma. The number of incidences ranged from two to eight. The incidence of cancer relative to synchronous cancer increased with the increased occurrence of MPCs. The primary cancer mainly occurred in tongue, gingiva and buccal sites, while the proportion of onset sites in gingiva, buccal and palate areas increased with the increased occurrence. Conclusions: M2 type macrophage counts and/or ratio to depth of infiltration were associated with the occurrence of MPCs, which could be used as a clinical indicator to distinguish single and MPCs in HNSCC. For early stage of HNSCC, patients with clinical characters of women, non-smoking, no alcohol addiction, no systemic medical history and sites of tongue, gingiva, and buccal should be paid more attention on their follow-up plan. The findings in the present study was also helpful to explore new treatment methods for the patients with MPCs.

[Current status of CD34+cell enumeration assay in clinical laboratories and its improvement]

Objective: To investigate the current status and problems of CD34⁺ cell enumeration in clinical laboratories and provide suggestions for the development of quality improvement programs. Methods: A total of 101 laboratories participating in the national external quality assessment program of CD34⁺cell enumeration were surveyed. Questionnaires and quality assessment materials were distributed to collect information on assay methodology and testing results. Quality control requirements for CD34⁺cell enumeration were determined according to the international guidelines, and the compliance of the surveyed laboratories was analyzed. Testing results were analyzed in groups and compared with the College of American Pathologists (CAP) quality assessment data. Results: A total of 97 laboratories returned the questionnaires and 99 laboratories returned the results of quality assessment materials. The questionnaire data showed high compliance rates of quality control requirements such as gating protocols, pipetting methods, and the number of cells acquired (92.8%, 83.9%, and 82.5% respectively). However, these laboratories had relatively low compliance rates such as the use of whole blood quality control materials for internal quality control, selection of erythrocyte lysing reagents, sample processing method, whether to report absolute count results, and quality control of equipment (5.2 %, 28.9%, 39.2%, 46.4%, and 55.7%, respectively). Testing results demonstrated that the coefficient of variation (CV) of percent counts was similar to the CAP quality assessment data, but the CV of absolute counts was greater than the CAP quality assessment data. Conclusions: Clinical laboratories have poor compliance with some quality control requirements and the variability of absolute count results between different laboratories is not satisfactory. Therefore, it is recommended that clinical laboratories should strengthen the training related to the quality control of CD34⁺cell enumeration, especially the absolute counting.

Slow-release lubrication of artificial joints using self-healing polyvinyl alcohol/polyethylene glycol/ graphene oxide hydrogel

New fabrication methods and lubrication materials must be developed to improve the lubrication performance of artificial joints and increase the lubrication duration. Herein, a novel polyvinyl alcohol/polyethylene glycol/graphene oxide (PVA/PEG/GO) hydrogel was prepared by a physical cross-linking method, and then the hydrogel and its sustained-release solution were used as lubricant for friction evaluation. The results demonstrated that the slow-release gel solution has good lubrication performance, and coefficient of friction (COF) is only 0.04, which is much lower than the COF of distilled water (about 0.08) under the same conditions. The structure characterization results revealed that no new materials are formed in the gel. The results of thermogravimetric analyses and differential scanning calorimetry demonstrated that the addition of GO may improve the network crosslinking structure of the PVA/PEG hydrogel and improve its mechanical strength. In addition, PVA/PEG/GO hydrogel has superior self-healing function. The self-healing hydrogel did not break again after being pulled under 200 G of weights. The PVA/PEG/GO hydrogel with excellent slow-release lubricating performance and self-healing properties provides a novel candidate for design of long-term lubricating artificial joints, and is expected to promote the progress of artificial joint lubrication applications.

Effect of xylanase and live yeast supplementation on growth performance, nutrient digestibility, and gut microbiome diversity of pigs

Effect of xylanase (Xyl) and live yeast (LY) supplementation on gut microbiome composition, growth performance, and nutrient digestibility of weanling pigs was determined. A total of 180 weanling pigs were assigned to five treatments from weaning to market. Treatments were designated based on whether Xyl, LY, or their combination were fed in the first 2 wk postweaning or thereafter until finishing at day 141 postweaning. Treatments were (days 1–15; days 15–141): control–control, control–Xyl, Xyl–Xyl, LY–Xyl, Xyl + LY–Xyl. Xylanase was added at 16 000 BXU·kg−1 and LY at 1 kg·t−1. Pigs fed with LY and LY + Xyl from days 0–15 had greater body weight and average daily gain at day 15 compared with control (P < 0.05). Glucose transporter 2 mRNA was higher in LY and LY + Xyl groups on day 15 compared with control (P < 0.05). Xylanase supplementation from week 2 postweaning increased apparent total tract nutrient digestibility of gross energy, nitrogen, and phosphorus on day 43. Live yeast with or without Xyl improved growth performance in the first 2 wk after weaning; Xyl + LY–Xyl and control–Xyl groups had improved overall feed efficiency. In conclusion, LY and Xyl supplementation improved performance of weanling pigs in the first 2 wk after weaning with no effects on long-term growth performance.