[Epidemiological characteristics of diarrheagenic Escherichia coli infection in infectious diarrhea outpatients aged 15 years and older in Shanghai, 2014-2021]

Objective: To understand the epidemiological characteristics of diarrheagenic Escherichia (E. ) coli infection in infectious diarrhea outpatients aged 15 years and older in Shanghai and provide evidence for the development of disease control strategies. Methods: Based on multistage systematic sampling, diarrhea surveillance was conducted in 22 sentinel hospitals in Shanghai, the information about cases' demographic, clinical, and epidemiological characteristics were collected. Stool samples were collected for the detection and typing of diarrheagenic E. coli by local centers for disease control and prevention. The positive rate of diarrheagenic E. coli in different populations and seasons from 2014 to 2021 were analyzed. Statistical analysis was conducted by using χ2 test. Results: In 15 185 diarrhea cases, 8.05% (1 222/15 185) were positive for diarrheagenic E. coli. The positive rate was higher in men (8.74%, 684/7 824) than in women (7.31%, 538/7 361). The positive rate was highest in age group 15-29 years (9.14%, 335/3 665) and the annual positive rate was highest in 2021 (10.21%, 83/813), the differences were all significant (P<0.05). In the 1 264 strains of diarrheagenic E. coli analyzed through PCR, enterotoxingenic E. coli was the most frequently identified pathogen (50.24%, 635/1 264), followed by enteroadhesive E. coli (27.93%, 353/1 264), and enteropathogenic E. coli (21.36%, 270/1 264). The positive rate of diarrheagenic E. coli showed obvious seasonality with peak in summer (13.92%, 774/5 562) (χ2=495.73, P<0.001). Conclusions: Diarrheagenic E. coli has become a prominent pathogen in infectious diarrhea cases in Shanghai, the disease can occur all the year round with incidence peak during summer and autumn. Predominant subtypes included enterotoxingenic E. coli, enteroadhesive E. coli and enteropathogenic E. coli. Targeted prevention and control strategies are needed for diarrheagenic E. coli-induced infectious diarrhea in different age groups, seasons and for different types of infections.

Neuroprotection of low dose carbon monoxide in Parkinson's disease models commensurate with the reduced risk of Parkinson's among smokers

Paradoxically, cigarette smoking is associated with a reduced risk of Parkinson's disease (PD). This led us to hypothesize that carbon monoxide (CO) levels, which are constitutively but modestly elevated in smokers, might contribute to neuroprotection. Using rodent models of PD based on α-synuclein (αSyn) accumulation and oxidative stress, we show that low-dose CO mitigates neurodegeneration and reduces αSyn pathology. Oral CO administration activated signaling cascades mediated by heme oxygenase-1 (HO-1), which have been implicated in limiting oxidative stress, and in promoting αSyn degradation, thereby conferring neuroprotection. Consistent with a neuroprotective effect of smoking, HO-1 levels in cerebrospinal fluid were higher in human smokers compared to nonsmokers. Moreover, in PD brain samples, HO-1 levels were higher in neurons without αSyn pathology. Thus, CO in rodent PD models reduces pathology and increases oxidative stress responses, phenocopying possible protective effects of smoking evident in PD patients. These data highlight the potential for low-dose CO modulated pathways to slow symptom onset and limit pathology in PD patients.

In Vivo Effect of Single Intra-Articular Injection of Tranexamic Acid on Articular Cartilage and Meniscus: Study in a Rat Model

BACKGROUND

Tranexamic acid (TXA) has been increasingly used in arthroscopic surgery to prevent hemarthrosis. Despite its effectiveness, safety concerns have been raised regarding its potential cytotoxicity to articular cartilage and meniscus following intra-articular injection.

METHODS

To evaluate the impact of TXA on cartilage and meniscus, a rat model of knee instability was utilized wherein anterior cruciate ligament (ACL) transection surgery was followed by a single intra-articular injection of TXA at varying concentrations (0, 20, 50, 100, and 150 mg/mL) in saline solution. Cell viability assessment of the cartilage and meniscus (n = 6 per group) was conducted at 24 hours, and gross observation and histological analysis of the medial tibial plateau and medial meniscus were conducted at 2, 4, and 8 weeks (n = 6 per group and time point).

RESULTS

The chondrocyte viability was significantly decreased in the 50, 100, and 150 mg/mL TXA groups compared with the specimens injected with saline solution only (saline group) (p = 0.001, p < 0.001, p < 0.001, respectively), as was meniscal cell viability (p = 0.042, p < 0.001, p < 0.001, respectively). At week 8, the saline and 20 and 50 mg/mL groups showed relatively normal appearances, whereas the 100 and 150 mg/mL groups exhibited increased and varying severity of cartilage and meniscal degeneration. In the 150 mg/mL group, the mean Osteoarthritis Research Society International score was significantly higher than that in the saline and 20 mg/mL groups (p = 0.010 and p = 0.007). Additionally, the mean meniscus score in the 150 mg/mL group was significantly higher than that in the saline, 20 mg/mL, and 50 mg/mL groups (p = 0.020, p = 0.021, p = 0.031, respectively).

CONCLUSIONS

Our findings indicate that concentrations of TXA at or above 100 mg/mL can lead to decreased cell viability in both cartilage and meniscus, resulting in significant cartilage degeneration in rats with ACL transection. Furthermore, the use of 150 mg/mL of TXA led to significant meniscal degeneration.

CLINICAL RELEVANCE

It is prudent to avoid using concentrations of TXA at or above 100 mg/mL for intra-articular injection, as such concentrations may result in adverse effects on the cartilage and meniscus.

Dual-response of multi-functional microsphere system to ultrasound and microenvironment for enhanced bone defect treatment

Using bone tissue engineering strategies to achieve bone defect repair is a promising modality. However, the repair process outcomes are often unsatisfactory. Here we properly designed a multi-functional microsphere system, which could deliver bioactive proteins under the dual response of ultrasound and microenvironment, release microenvironment-responsive products on demand, reverse bone injury microenvironment, regulate the immune microenvironment, and achieve excellent bone defect treatment outcomes. In particular, the MnO2 introduced into the poly(lactic-co-glycolic acid) (PLGA) microspheres during synthesis could consume the acid produced by the degradation of PLGA to protect bone morphogenetic protein-2 (BMP-2). More importantly, MnO2 could consume reactive oxygen species (ROS) and produce Mn2+ and oxygen (O2), further promoting the repair of bone defects while reversing the microenvironment. Moreover, the reversal of the bone injury microenvironment and the depletion of ROS promoted the polarization of M1 macrophages to M2 macrophages, and the immune microenvironment was regulated. Notably, the ultrasound (US) irradiation used during treatment also allowed the on-demand release of microenvironment-responsive products. The multi-functional microsphere system combines the effects of on-demand delivery, reversal of bone injury microenvironment, and regulation of the immune microenvironment, providing new horizons for the clinical application of protein delivery and bone defect repair.

Ang1/Tie2/VE-Cadherin Signaling Regulates DPSCs in Vascular Maturation

Adding dental pulp stem cells (DPSCs) to vascular endothelial cell-formed vessel-like structures can increase the longevity of these vessel networks. DPSCs display pericyte-like cell functions and closely assemble endothelial cells (ECs). However, the mechanisms of DPSC-derived pericyte-like cells in stabilizing the vessel networks are not fully understood. In this study, we investigated the functions of E-DPSCs, which were DPSCs isolated from the direct coculture of human umbilical vein endothelial cells (HUVECs) and DPSCs, and T-DPSCs, which were DPSCs treated by transforming growth factor beta 1 (TGF-β1), in stabilizing blood vessels in vitro and in vivo. A 3-dimensional coculture spheroid sprouting assay was conducted to compare the functions of E-DPSCs and T-DPSCs in vitro. Dental pulp angiogenesis in the severe combined immunodeficiency (SCID) mouse model was used to explore the roles of E-DPSCs and T-DPSCs in vascularization in vivo. The results demonstrated that both E-DPSCs and T-DPSCs possess smooth muscle cell-like cell properties, exhibiting higher expression of the mural cell-specific markers and the suppression of HUVEC sprouting. E-DPSCs and T-DPSCs inhibited HUVEC sprouting by activating TEK tyrosine kinase (Tie2) signaling, upregulating vascular endothelial (VE)-cadherin, and downregulating vascular endothelial growth factor receptor 2 (VEGFR2). In vivo study revealed more perfused and total blood vessels in the HUVEC + E-DPSC group, HUVEC + T-DPSC group, angiopoietin 1 (Ang1) pretreated group, and vascular endothelial protein tyrosine phosphatase (VE-PTP) inhibitor pretreated group, compared to HUVEC + DPSC group. In conclusion, these data indicated that E-DPSCs and T-DPSCs could stabilize the newly formed blood vessels and accelerate their perfusion. The critical regulating pathways are Ang1/Tie2/VE-cadherin and VEGF/VEGFR2 signaling.

Hydrothermally treated coral scaffold promotes proliferation of mesenchymal stem cells and enhances segmental bone defect healing

Introduction: Synthetic hydroxyapatite (HAp) scaffolds have shown promising therapeutic outcomes in both animals and patients. In this study, we aim to evaluate the chemical and physical phenotype, biocompatibility, and bone repair effects of hydrothermally treated coral with natural coral and synthetic HAp. Methods: The phase composition, surface pattern, 3D structures, and porosity of the scaffolds were characterized, and cell viability, proliferation, and osteogenic differentiation of mesenchymal stem cells (MSCs) after seeding onto the scaffold were determined. The scaffolds were implanted into rats to assess their bone repair effects using micro-CT analysis, mechanical testing, and histological staining. Results: The results showed that the phase composition, porous structure, and porosity of hydrothermally treated coral were comparable to pure HAp scaffold. While only the natural coral happens to be dominantly calcium carbonate. Higher cell proliferation and osteogenic differentiation potential were observed in the hydrothermally treated coral scaffold compared to natural coral and pure HAp. Histological results also showed increased new bone formation in the hydrothermally treated coral group. Discussion: Overall, our study suggests that hydrothermal modification enhances the cytocompatibility and therapeutic capacity of coral without altering its physical properties, showing superior effectiveness in bone repair to synthetic HAp.

[Analysis and prediction of burden of viral hepatitis C-associated diseases in China from 1990 to 2044]

OBJECTIVE

To measure the burden of hepatitis C-associated diseases in China from 1990 to 2019, and to predict its changes from 2020 to 2044, so as to provide insights into formulation of the targeted hepatitis C control strategy.

METHODS

The total burden due to hepatitis C-associated diseases in China from 1990 to 2019 were extracted from the Global Burden of Disease 2019 (GBD 2019) data resources, and the trends in age-standardized prevalence, incidence, mortality and disability-adjusted life years (DALYs) rate of hepatitis C-associated acute hepatitis C (AHC), chronic liver diseases (CLD) and liver cancer in China from 1990 to 2019 were evaluated in China from 1990 to 2019 using estimated annual percentage change (EAPC). In addition, the changes in the burden of hepatitis C-associated diseases were predicted in China from 2020 to 2044 using a Bayesian model.

RESULTS

The prevalence, incidence, mortality and DALY rate of hepatitis C-associated diseases all appeared an overall tendency towards a decline in China from 1990 to 2019 (EAPC = -2.64%, -2.24%, -3.81% and -3.90%, respectively); however, there was a minor rise in the incidence and prevalence of hepatitis C-associated diseases from 2015 to 2019. The overall prevalence of hepatitis C-associated diseases reduced from 2 152.7/105 in 1990 to 1 254.1/105 in 2019 in China, with a reduction of 41.7%. The overall incidence reduced from 87.9/105 in 1990 to 55.0/105 in 2019 in China, with a reduction of 37.4%, and the highest incidence was seen for AHC, followed by CLD and liver cancer. The overall mortality and DALY rate of hepatitis C-associated diseases was 4.0/105 and 100.8/105 in China from 1990 to 2019, with CLD showing the largest contributions to the gross mortality and DALY. The mortality and DALY rate of hepatitis C-associated diseases were 5.5/105 and 142.4/105 among men in China in 2019, which were both much higher than among women (2.8/105 and 60.3/105, respectively), and the overall prevalence (1 604.9/105), mortality (30.2/105) and DALYs (437.1/105) of hepatitis C-associated diseases were all highest among patients at ages of 70 years and older, and the highest incidence was seen among patients at ages of 0 to 9 years (167.3/105). The incidence of hepatitis C-associated diseases was predicted to rise in China from 2020 to 2044; however, the DALY rate was projected to appear a tendency towards a decline.

CONCLUSIONS

Although the burden of hepatitis C-associated diseases showed a tendency towards a decline in China from 1990 to 2019, the burden remained high, and was predicted to slightly rise from 2020 to 2044. High attention should be paid to screening of hepatitis C among infants and treatment among adults.

[Burden of hepatitis B-associated diseases in China from 1990 to 2030]

OBJECTIVE

To measure the burden of hepatitis B-associated diseases in China from 1990 to 2019, and to predict its changes from 2020 to 2030.

METHODS

The age-standardized prevalence, incidence, mortality and disability-adjusted life years (DALY) rate of hepatitis B-associated diseases in China from 1990 to 2019 were extracted from the Global Burden of Disease 2019 (GBD 2019) data resources, and the trends in burdens of hepatitis B-associated diseases were evaluated from 1990 to 2019 using estimated annual percentage change (EAPC) and annual percent change (APC). In addition, the changes in the burden of hepatitis B-associated diseases were predicted in China from 2020 to 2023 using the Bayesian model.

RESULTS

The overall incidence of hepatitis B-associated diseases reduced from 2 725.98/105 in 1990 to 1 397.31/105 in 2019 in China [estimated annual percentage change (EAPC) = -2.35%, 95% confidential interval (CI): (-2.58%, -2.13%)], with a reduction in the prevalence from 12 239.53/105 in 1990 to 6 566.12/105 in 2019 [EAPC = -2.34%, 95% CI: (-2.54%, -2.14%)], a reduction in the mortality from 24.67/105 in 1990 to 8.07/105 in 2019 [EAPC = -4.92%, 95% CI: (-5.37%, -4.47%)], and a reduction in the DALY rate from 793.38/105 in 1990 to 247.71/105 in 2019 [(EAPC = -5.15%, 95% CI: (-5.64%, -4.66%)]. The DALY rate of hepatitis B-associated diseases were mainly attributed to liver cancer, and the DALY rate of hepatitis B-associated diseases appeared a tendency towards a rise in China from 2012 to 2019 [APC = 1.30%, 95% CI: (0.16%, 2.45%)]. The overall burden of hepatitis Bassociated diseases was higher in males than in females, and the DALY rate of hepatitis B-associated diseases increased with age, with the greatest DALY rate seen among patients at ages of 50 to 69 years. The overall incidence of hepatitis B-associated diseases was projected to be 866.79/105 in China in 2030, with the greatest incidence seen in acute hepatitis B (854.87/105), and the burden of hepatitis B-associated diseases was predicted to decline in China from 2020 to 2030; however, the burden of liver disease was projected to appear a tendency towards a rise.

CONCLUSIONS

The burden of hepatitis B-associated diseases appears an overall tendency towards a decline in China from 1990 to 2030; however, the burden of liver cancer appears a tendency towards aggravation. Early diagnosis and treatment of liver cancer should be given a high priority.

[Advances in the applications of dissolving polymer microneedles for delivering drugs in ocular diseases]

Due to the unique anatomical structure and physiological barriers of the eye, drug delivery for ocular diseases presents a formidable challenge. Conventional methods of ocular drug administration often suffer from limitations such as low drug bioavailability and a lack of tissue targeting, necessitating multiple administrations to achieve the desired therapeutic drug concentrations. In recent years, microneedles, known for their attributes of safety, minimally invasive application, and high efficiency, have found widespread application in ocular drug delivery research. Among the various types of microneedles, dissolving polymer microneedles have emerged as a prominent focus in the field of ocular drug delivery due to their distinct advantages over other microneedle types. This article provides a comprehensive summary and outlook on the progress in the application of dissolving polymer microneedles for drug delivery in ocular diseases.

Genetically Engineered Biomimetic Nanoparticles for Targeted Delivery of mRNA to Treat Rheumatoid Arthritis

In addition to inhibiting persistent inflammation, phosphatase and tensin homolog deleted from chromosome 10 (PTEN) is known as an important therapeutic target for alleviating rheumatoid arthritis (RA) symptoms. Modulation of PTEN gene expression in synovial tissue using messenger RNA (mRNA) is a promising approach to combat RA. However, mRNA therapeutics are often hampered by unsatisfactory stability and inefficient localization in synovial tissue. In this study, a genetically engineered biomimetic membrane-coated mRNA (MR@P-mPTEN) carrier that effectively delivers mRNA-PTEN (mPTEN) directly to the RA joint is presented. By overexpressing tumor necrosis factor (TNF-α) receptors on macrophage biomimetic membranes via plasmid transfection, decoys that reduce inflammatory pathway activation are prepared for TNF-α. The resulting construct, MR@P-mPTEN, shows good stability and RA targeting based on in vivo fluorescence imaging. It is also found that MR@P-mPTEN competitively binds TNF-α and activates the PTEN pathway in vitro and in vivo, thereby inhibiting synovitis and joint damage. Clinical micro-computed tomography and histological analyses confirm the treatment effects. These results suggest that the genetically engineered biomimetic therapeutic platform MR@P-mPTEN both inhibits pro-inflammatory cytokines and upregulates PTEN protein expression to alleviate RA damage, providing a new a new combination strategy for RA treatment.

Effects of dietary methionine supplementation from different sources on growth performance and meat quality of barrows and gilts

Methionine is indispensable for growth and meat formation in pigs. However, it is still unclear that increasing dietary sulphur-containing amino acid (SAA) levels using different methionine sources affects the growth performance and meat quality of barrows and gilts. To investigate this, 144 pigs (half barrows and half gilts) were fed the control (100% SAA, CON), DL-Methionine (125% SAA, DL-Met)-supplemented, or OH-Methionine (125% SAA, OH-Met)-supplemented diets during the 11-110 kg period. The results showed that plasma methionine levels varied among treatments during the experimental phase, with increased plasma methionine levels observed following increased SAA consumption during the 25-45 kg period. In contrast, pigs fed the DL-Met diet had lower plasma methionine levels than those fed the CON diet (95-110 kg). Additionally, gilts fed the DL-Met or OH-Met diets showed decreased drip loss in longissimus lumborum muscle (LM) compared to CON-fed gilts. OH-Met-fed gilts had higher pH45min values than those fed the CON or DL-Met diets, whereas OH-Met-fed barrows had higher L45min values than those fed the CON or DL-Met diets. Moreover, increased consumption of SAA, regardless of the methionine source, tended to decrease the shear force of the LM in pigs. In conclusion, this study indicates that increasing dietary levels of SAA (+25%) appeared to improve the meat quality of gilts by decreasing drip loss and increasing meat tenderness.

Single-stage computer-assisted approach for tumour resection and functional restoration of Brown class III maxillary defects-titanium mesh and zygomatic implants combined with vascularized anterolateral thigh flap

The functional restoration of Brown class III maxillary defects is a challenging endeavour in oral and maxillofacial surgery. Conventional reconstruction techniques with osseous free flaps have certain limitations, such as the need for multiple operations and greater patient morbidity. This study introduces a single-stage computer-assisted approach for tumour resection and functional restoration of these defects using titanium mesh, zygomatic implants, and a vascularized anterolateral thigh flap (ALTF). Virtual surgical planning was used to simulate tumour resection, titanium mesh placement, and zygomatic implant insertion. Surgery was performed under the guidance of mixed reality and surgical navigation. The tumour was resected by total hemimaxillectomy, and the reconstruction was performed using a pre-bent patient-specific titanium mesh for the orbital floor and two zygomatic implants placed and exposed through tunnels in an ALTF. The ALTF survived without any perioperative complications. A fixed prosthesis with built-in titanium frame was delivered 4 months postoperatively. At the 1-year follow-up, there was no tumour recurrence, the implants were osseointegrated, and aesthetics and masticatory function were satisfactory. An occlusal force of 155 N was attained on the reconstructed side, compared to 127 N on the non-surgical side.

Low-Dose Staphylococcal Enterotoxin C2 Mutant Maintains Bone Homeostasis via Regulating Crosstalk between Bone Formation and Host T-Cell Effector Immunity

Studies in recent years have highlighted an elaborate crosstalk between T cells and bone cells, suggesting that T cells may be alternative therapeutic targets for the maintenance of bone homeostasis. Here, it is reported that systemic administration of low-dose staphylococcal enterotoxin C2 (SEC2) 2M-118, a form of mutant superantigen, dramatically alleviates ovariectomy (OVX)-induced bone loss via modulating T cells. Specially, SEC2 2M-118 treatment increases trabecular bone mass significantly via promoting bone formation in OVX mice. These beneficial effects are largely diminished in T-cell-deficient nude mice and can be rescued by T-cell reconstruction. Neutralizing assays determine interferon gamma (IFN-γ) as the key factor that mediates the beneficial effects of SEC2 2M-118 on bone. Mechanistic studies demonstrate that IFN-γ stimulates Janus kinase/signal transducer and activator of transcription (JAK-STAT) signaling, leading to enhanced production of nitric oxide, which further activates p38 mitogen-activated protein kinase (MAPK) and Runt-related transcription factor 2 (Runx2) signaling and promotes osteogenic differentiation. IFN-γ also directly inhibits osteoclast differentiation, but this effect is counteracted by proabsorptive factors tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1β) secreted from IFN-γ-stimulated macrophages. Taken together, this work provides clues for developing innovative approaches which target T cells for the prevention and treatment of osteoporosis.

Selectively Irradiation of the Supraclavicular Area in Nasopharyngeal Carcinoma Treated with Intensity Modulated Radiotherapy

PURPOSE/OBJECTIVE(S)

The application of intensity-modulated radiotherapy (IMRT) has significantly improved the locoregional control and overall survival of patients with nasopharyngeal carcinoma (NPC), but how to deescalate the intensity of treatment to further reduce the side effects while ensuring the efficacy is the main concern of clinicians. Decreasing radiation volume is one of the hot research topics. Whole-neck irradiation is recommended for patients with cervical lymph node involvement, which includes levels IVb and Vc. Since the implementation of IMRT in our clinic, patients with only upper cervical lymph node invasion have not been irradiated in the levels IVb and Vc, and the regional control rate is comparable to that of other centers. This study intends to retrospectively analyze the feasibility of omitting levels IVb and Vc in patients with only upper cervical lymph node invasion, and provide a basis for the revision of international guideline for the delineation of the clinical target volume (CTV).

MATERIALS/METHODS

Patients with histologically confirmed NPC who completed IMRT successfully at our attending group between January 2014 to March 2018 were candidates for this study. Other eligibility criteria for analysis were as follows: (1) The first patient without distant metastasis; (2) Only patients with upper cervical lymph node invasion (only N1, N2, because the maximum diameter of the upper neck 6cm diagnosed as N3 patients were not included) (AJCC staging system, 8th edition); (3) Having complete baseline imaging data; (4) Over 3 months of follow-up; (5) Patients without previous history of malignant tumor and secondary cancer. According to the delineation of CTV in our protocol for patients with stage N1 and N2, levels IVb and Vc are not irradiated (i.e., retaining the original supraclavicular area). The main endpoints of the study were regional recurrence-free survival (RRFS) and recurrence rates in levels IVb and Vc.

RESULTS

In all, 363 patients with NPC and median follow-up of 61.9 months (range, 3.67-93.3) met the study inclusion criteria and comprise the dataset for the analysis. The overall survival, survival without local recurrence, survival without regional recurrence, and survival without distant metastasis at 3 and 5 years were 94.6% and 91.1%, 97.7% and 96.5%, 98.6% and 98.0%, 93.5% and 91.1%. At the final follow-up, 11 cases showed regional recurrence, and only one case (0.28%) showed recurrence in regions IVb and Vc, which were field recurrences, while the rest were intra-field recurrences.

CONCLUSION

Omitting levels Ⅳb and Ⅴc IMRT should be safe and feasible for patients who only had involvement of upper neck LNs. Further well-designed multicenter prospective trials should be conducted to confirm our results and further optimize the recommendation of the International Guideline.

Discovery of multipotent progenitor cells from human induced membrane: Equivalent to periosteum-derived stem cells in bone regeneration

Background

The periosteum stem cells (PSCs) plays a critical role in bone regeneration and defect reconstruction. Insertion of polymethyl methacrylate (PMMA) bone cement can form an induced membrane(IM) and showed promising strategy for bone defect reconstruction, the underlying mechanism remains unclear. Our study sought to determine whether IM-derived cells(IMDCs) versus PSCs have similar characteristics in bone regeneration.

Methods

IM and periosteum were harvested from ten bone defect patients treated with PMMA, the IMDCs and PSCs were isolated respectively. Morphological, functional and molecular evaluation was performed and matched for comparison.

Results

Both progenitor-like IMDCs and PSCs were successfully isolated. In vitro, we found IMDCs were similar to PSCs in morphology, colony forming capacity and expression of surface marker(CD90+, CD73+, CD105+, CD34-/CD45-). Meanwhile, these IMSCs displayed multipotency with chondrogenic, adipogenic and osteogenic differentiation, but differed in some IMSCs(3/10) population showing relatively poor osteogenic differentiation. The molecular profiles suggests that cell cycle and DNA replication signaling pathways were associated with these varying osteogenic potential. In vivo, we established a cell-based tissue-engineered bone by seeding IMDSs/PSCs to demineralized bone matrix (DBM) scaffold and demonstrated both IMDSs and PSCs enhanced bone regeneration in SCID mice bone defect model compared with DBM alone.

Conclusion

Our data demonstrated IM containing multipotent progenitor cells similar to that periosteum promoting bone regeneration, and indicated the existence of multiple subsets in osteogenic differentiation. Overall, the study provided a cellular and molecular insights in understanding the successful or failed outcome of bone defect healing.The translational potential of this article: This study confirmed IMDCs and PSCs share similar regeneration capacity and inform a translation potential of that cellular therapy applying IMDCs in bone defect repair.

Upregulation of FTX Promotes Osteosarcoma Tumorigenesis by Increasing SOX4 Expression via miR-214-5p [Retraction]

[This retracts the article DOI: 10.2147/OTT.S238070.].

An osteoinductive and biodegradable intramedullary implant accelerates bone healing and mitigates complications of bone transport in male rats

Bone transport is a surgery-driven procedure for the treatment of large bone defects. However, challenging complications include prolonged consolidation, docking site nonunion and pin tract infection. Here, we develop an osteoinductive and biodegradable intramedullary implant by a hybrid tissue engineering construct technique to enable sustained delivery of bone morphogenetic protein-2 as an adjunctive therapy. In a male rat bone transport model, the eluting bone morphogenetic protein-2 from the implants accelerates bone formation and remodeling, leading to early bony fusion as shown by imaging, mechanical testing, histological analysis, and microarray assays. Moreover, no pin tract infection but tight osseointegration are observed. In contrast, conventional treatments show higher proportion of docking site nonunion and pin tract infection. The findings of this study demonstrate that the novel intramedullary implant holds great promise for advancing bone transport techniques by promoting bone regeneration and reducing complications in the treatment of bone defects.

Biomimetic Nanofibrillar Hydrogel with Cell-Adaptable Network for Enhancing Cellular Mechanotransduction, Metabolic Energetics, and Bone Regeneration

The natural extracellular matrix, with its heterogeneous structure, provides a stable and dynamic biophysical framework and biochemical signals to guide cellular behaviors. It is challenging but highly desirable to develop a synthetic matrix that emulates the heterogeneous fibrous structure with macroscopic stability and microscopical dynamics and contains inductive biochemical signals. Herein, we introduce a peptide fiber-reinforced hydrogel in which the stiff ß-sheet fiber functions as a multivalent cross-linker to enhance the hydrogel's macroscopic stability. The dynamic imine cross-link between the peptide fiber and polymer network endows the hydrogel with a microscopically dynamic network. The obtained fibrillar nanocomposite hydrogel, with its cell-adaptable dynamic network, enhances cell-matrix and cell-cell interactions and therefore significantly promotes the mechanotransduction, metabolic energetics, and osteogenesis of encapsulated stem cells. Furthermore, the hydrogel can codeliver a fiber-attached inductive drug to further enhance osteogenesis and bone regeneration. We believe that our work provides valuable guidance for the design of cell-adaptive and bioactive biomaterials for therapeutic applications.

[Clinical characteristics of 13 cases with entrapped temporal horn syndrome and efficacy of refined temporal-to-frontal horn shunt]

Thirteen consecutive patients with entrapped temporal horn syndrome in the Department of Neurosurgery of Beijing Tiantan Hospital from February 2018 to September 2022 were retrospectively analyzed, and there were 5 males and 8 females, with a mean age of (43±21) years. Increased intracranial pressure caused by hydrocephalus was the main clinical symptom. All the patients underwent refined temporal-to-frontal horn shunt, and all the symptoms were improved after surgery. Postoperative Karnofsky performance score (KPS) [90 (90, 100)] was higher than preoperative KPS [57 (40, 70)] (P=0.001). However, postoperative entrapped temporal horn volume [13.85 (8.90, 15.25) cm³] decreased, compared with preoperative volume [66.52 (38.65, 88.65) cm³] (P=0.001). Likewise, postoperative midline shift [0.77 (0, 1.50) mm] was longer than preoperative midline shift [6.69 (2.50, 10.00) mm] (P=0.002). No surgery-related complications were observed after the operation. Therefore, the refined temporal-to-frontal horn shunt is safe and effective treatment for entrapped temporal horn syndrome, with favorable outcomes.

Improved Measurement of the Evolution of the Reactor Antineutrino Flux and Spectrum at Daya Bay

Reactor neutrino experiments play a crucial role in advancing our knowledge of neutrinos. In this Letter, the evolution of the flux and spectrum as a function of the reactor isotopic content is reported in terms of the inverse-beta-decay yield at Daya Bay with 1958 days of data and improved systematic uncertainties. These measurements are compared with two signature model predictions: the Huber-Mueller model based on the conversion method and the SM2018 model based on the summation method. The measured average flux and spectrum, as well as the flux evolution with the ^{239}Pu isotopic fraction, are inconsistent with the predictions of the Huber-Mueller model. In contrast, the SM2018 model is shown to agree with the average flux and its evolution but fails to describe the energy spectrum. Altering the predicted inverse-beta-decay spectrum from ^{239}Pu fission does not improve the agreement with the measurement for either model. The models can be brought into better agreement with the measurements if either the predicted spectrum due to ^{235}U fission is changed or the predicted ^{235}U, ^{238}U, ^{239}Pu, and ^{241}Pu spectra are changed in equal measure.

[Analysis on missed diagnosis or misdiagnosis of anomalous origin of left coronary artery from pulmonary artery by echocardiography from one single medical center]

Objectives: To analyze the reasons of missed diagnosis or misdiagnosis on anomalous origin of left coronary artery from pulmonary artery (ALCAPA) by echocardiography. Methods: This is a retrospective study. Patients with ALCAPA who underwent surgical treatment in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from August 2008 to December 2021 were included. According to the results of preoperative echocardiography and surgical diagnosis, the patients were divided into confirmed group or missed diagnosis/misdiagnosis group. The results of preoperative echocardiography were collected, and the specific echocardiographic signs were analyzed. According to the experience of the doctors, the echocardiographic signs were divided into four types, namely clear displayed, vague/doubtful displayed, no display and no notice, and the display rate of each sign was calculated (display rate=number of clearly displayed cases/total number of cases×100%). By referring the surgical data, we analyzed and recorded the pathological anatomy and pathophysiological characteristics of the patients, and the rate of missed diagnosis/misdiagnosis of echocardiography in patients with different characteristics was compared. Results: A total of 21 patients were enrolled, including 11 males, aged 1.8 (0.8, 12.3) years (range 1 month to 47 years). Except for one patient with anomalous origin of left anterior descending artery, the others were all originated from the main left coronary artery (LCA). There were 13 cases of ALCAPA in infant and children, and 8 cases of adult ALCAPA. There were 15 cases in the confirmed group (diagnostic accuracy was 71.4% (15/21)), and 6 cases in the missed diagnosis/misdiagnosis group (three cases were misdiagnosed as primary endocardial fibroelastosis, two cases were misdiagnosed as coronary-pulmonary artery fistula; and one case was missed diagnosis). The working years of the physicians in the confirmed group were longer than those in the missed diagnosis/misdiagnosed group ((12.8±5.6) years vs. (8.3±4.7) years, P=0.045). In infants with ALCAPA, the detection rate of LCA-pulmonary shunt (8/10 vs. 0, P=0.035) and coronary collateral circulation (7/10 vs. 0, P=0.042) in confirmed group was higher than that in missed diagnosis/misdiagnosed group. In adult ALCAPA patients, the detection rate of LCA-pulmonary artery shunt was higher in confirmed group than that in missed diagnosis/misdiagnosed group (4/5 vs. 0, P=0.021). The missed diagnosis/misdiagnosis rate of adult type was higher than that of infant type (3/8 vs. 3/13, P=0.410). The rate of missed diagnosis/misdiagnosis was higher in patients with abnormal origin of branches than that of abnormal origin of main trunk (1/1 vs. 5/21, P=0.028). The rate of missed diagnosis/misdiagnosis in patients with LCA running between the main and pulmonary arteries was higher than that distant from the main pulmonary artery septum (4/7 vs. 2/14, P=0.064). The rate of missed diagnosis/misdiagnosis in patients with severe pulmonary hypertension was higher than that in patients without severe pulmonary hypertension (2/3 vs. 4/18, P=0.184). The reasons with an echocardiography missed diagnosis/misdiagnosis rate of≥50% included that (1) the proximal segment of LCA ran between the main and pulmonary arteries; (2) abnormal opening of LCA at the right posterior part of the pulmonary artery; (3) abnormal origin of LCA branches; (4) complicated with severe pulmonary hypertension. Conclusions: Echocardiography physicians' knowledge of ALCAPA and diagnostic vigilance are critical to the accuracy of diagnosis. Attention should be paid to the pediatric cases with no obvious precipitating factors of left ventricular enlargement, regardless of whether the left ventricular function is normal or not, the origin of coronary artery should be routinely explored.

HIF-1α dependent RhoA as a novel therapeutic target to regulate rheumatoid arthritis fibroblast-like synoviocytes migration in vitro and in vivo

Objective

The purpose of this work is to investigate how the Rho family of GTPases A (RhoA) mediates the pathogenesis of rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS).

Methods

The expression of RhoA in the synovial tissues of RA and Healthy people (Control) was detected using immunohistochemistry methods. The expression of RhoA and hypoxia-inducible factor-1α (HIF-1α) is inhibited by small interfering RNAs (siRNAs). The inhibition effect on RA-FLS migration was further investigated. The protein expression level of HIF-1α, RhoA, focal adhesion kinase (FAK), and myosin light chain (MLC) was also analysed using western blotting (WB). DBA1 mice were immunised with the mixture of bovine type II collagen and Freund's adjuvant to establish collagen induced arthritis (CIA) mouse model. Lip-siRhoA is administered through joint injection every two days. Micro-computed tomography (micro-CT) was used to detect mouse ankle joint destruction and evaluate the bone loss of the periarticular side. Destruction of the ankle articular cartilage was tested by histology. Expressions of P-RhoA, P-FAK and P-MLC in the ankle joint was detected by immunohistochemistry assay.

Results

The expression level of RhoA in the synovial tissues of RA patients was significantly higher than that in control group. Hypoxia was able to up-regulate the expression of RhoA. Whereas, HIF-1α siRNA (siHIF-1α) could down-regulate the expression of RhoA. Additionally, both of siHIF-1α and RhoA siRNA (siRhoA) delivered by liposome (Lip-siHIF-1α and Lip-siRhoA) were found to suppress FAK and MLC phosphorylation in vitro. In CIA mouse model, Lip-siRhoA was demonstrated to ameliorate the destruction of ankle joint and reduce the severity of ankle joint cartilage damage by micro-CT and histological staining, respectively. Therefore, inhibition of FLS cell migration can protect articular bone from destruction. Furthermore, the expression of P-RhoA, P-FAK and P-MLC was evaluated and found to be down-regulated by Lip-siRhoA in vivo.

Conclusion

The results demonstrated that under hypoxic environment, HIF-1α dependent RhoA pathway played an important role on cytoskeleton remodelling and RA-FLS migration. Through down-regulating RhoA expression, it could effectively treat RA in vitro and in vivo.

The translational potential of this article

Our study provides new evidence for the potential clinical application of RhoA as a candidate for the treatment of RA.

Precision Measurement of Reactor Antineutrino Oscillation at Kilometer-Scale Baselines by Daya Bay

We present a new determination of the smallest neutrino mixing angle θ_{13} and the mass-squared difference Δm_{32}^{2} using a final sample of 5.55×10^{6} inverse beta-decay (IBD) candidates with the final-state neutron captured on gadolinium. This sample is selected from the complete dataset obtained by the Daya Bay reactor neutrino experiment in 3158 days of operation. Compared to the previous Daya Bay results, selection of IBD candidates has been optimized, energy calibration refined, and treatment of backgrounds further improved. The resulting oscillation parameters are sin^{2}2θ_{13}=0.0851±0.0024, Δm_{32}^{2}=(2.466±0.060)×10^{-3}  eV^{2} for the normal mass ordering or Δm_{32}^{2}=-(2.571±0.060)×10^{-3}  eV^{2} for the inverted mass ordering.

Long Non-Coding RNA Malat1 Increases the Rescuing Effect of Quercetin on TNFα-Impaired Bone Marrow Stem Cell Osteogenesis and Ovariectomy-Induced Osteoporosis

Osteoporosis, a common systematic bone homeostasis disorder related disease, still urgently needs innovative treatment methods. Several natural small molecules were found to be effective therapeutics in osteoporosis. In the present study, quercetin was screened out from a library of natural small molecular compounds by a dual luciferase reporter system. Quercetin was found to upregulate Wnt/β-catenin while inhibiting NF-κB signaling activities, and thereby rescuing osteoporosis-induced tumor necrosis factor alpha (TNFα) impaired BMSCs osteogenesis. Furthermore, a putative functional lncRNA, Malat1, was shown to be a key mediator in quercetin regulated signaling activities and TNFα-impaired BMSCs osteogenesis, as mentioned above. In an ovariectomy (OVX)-induced osteoporosis mouse model, quercetin administration could significantly rescue OVX-induced bone loss and structure deterioration. Serum levels of Malat1 were also obviously rescued in the OVX model after quercetin treatment. In conclusion, our study demonstrated that quercetin could rescue TNFα-impaired BMSCs osteogenesis in vitro and osteoporosis-induced bone loss in vivo, in a Malat1-dependent manner, suggesting that quercetin may serve as a therapeutic candidate for osteoporosis treatment.

[Analysis of the difference in MGMT promoter status in gliomas and its significance in prognosis assessment]

The data of 1 268 newly diagnosed gliomas from the Fourth Ward of Neurosurgery Department of Beijing Tiantan Hospital between April 2013 and March 2022 were retrospectively analyzed. Based on postoperative pathology, the gliomas were divided into groups: oligodendrogliomas (n=308), astrocytomas (n=337) and glioblastomas (n=623). According to the O6-methylguanine-DNA methyl transferase (MGMT) promoter status defined by the 12% of best cut-off value in previous research results, patients were divided into methylation group (n=763) and non-methylation group (n=505). Methylation level [M (Q₁, Q₃)] in patients with glioblastoma, astrocytoma and oligodendroglioma was 6% (2%, 24%), 17% (10%, 28%) and 29% (19%, 40%), respectively (P<0.001). Compared with non-methylation patients, the progression-free survival (PFS) and overall survival (OS) of glioblastomas patients with methylation of MGMT promoter demonstrated more favorable prognosis [M (Q₁, Q₃)]) of PFS: 14.0 (6.0, 36.0) months vs 8.0 (4.0, 15.0) months, P<0.001; M (Q₁, Q₃) of OS: 29.0 (17.0, 60.5) months vs 16.0 (11.0, 26.5) months, P<0.001]. In astrocytomas patients, the PFS was much longer for those with methylation [the median PFS of patients with methylation was not observed at the end of follow-up, but those without methylation showed a median PFS of 46.0 (29.0, 52.0) months] (P=0.001). However, no statistically significant difference was observed in OS [the median OS of patients with methylation was not observed at the end of follow-up, but those without methylation had a median OS of 62.0 (46.0, 98.0) months] (P=0.085). In oligodendrogliomas patients, no statistically significant differences of PFS and OS were observed between patients with methylation and those without methylation. MGMT promoter status was a related factor affecting PFS and OS in glioblastomas (PFS: HR=0.534,95%CI: 0.426-0.668, P<0.001; OS: HR=0.451, 95%CI: 0.353-0.576, P<0.001). Moreover, MGMT promoter status was also a related factor affecting PFS in astrocytomas (HR=0.462, 95%CI: 0.221-0.966, P=0.040), but not for OS (HR=0.664, 95%CI: 0.259-1.690, P=0.389). The methylation level of MGMT promoter differed substantially in different types of gliomas, and the status of MGMT promoter profoundly affected the prognosis of glioblastomas.

[Clinical analysis of 11 patients with neuroendocrine carcinoma in maxillofacial region]

Objective: To investigate the clinicopathological features, treatment and prognosis of maxillofacial neuroendocrine carcinoma. Methods: A total of 11 patients with maxillofacial neuroendocrine carcinoma diagnosed in the Department of Pathology of The First Affiliated Hospital of Zhengzhou University from December 2010 to July 2022 were retrospectively enrolled, including 8 males and 3 females, aged (65.2±9.5) years (ranged from 49 to 87 years), with a disease course of 0.5 to 6.0 months. The clinicopathological data including head and neck CT, MRI and treatment methods were analyzed. Results: Submandibular gland and maxilla were involved in 3 cases, parapharynx in 2 cases, and face, tongue root and soft palate in 1 case respectively. Clinically, the initial symptom is a rapidly growing painless or tender mass, which may be accompanied by restricted mouth opening, dysphagia, and local numbness after invasion of masticatory muscles and nerves. The tumors were all invasive and low-density, with unclear boundaries from the surrounding tissues. Among the patients, 9 received surgical treatment, and 5 received adjuvant treatment after surgery (2 received chemotherapy, 3 received radiotherapy+chemotherapy). According to the 5th edition of the World Health Organization classification of head and neck tumors in 2022, there were 1 case (1/11) with poorly differentiated large cells and 10 cases (10/11) with poorly differentiated small cells. Histologically, the macrocell type is composed of large cells with rough chromatin, obvious vacuolar nucleolus, protruding nucleolus, and necrosis. The small cell type is dominated by small blue round cells with neuroendocrine characteristics, with active growth and multifocal necrosis. Immunohistochemical staining showed that cytokeratin (CK), epithelial membrane antigen (EMA) and synaptophysin (Syn) were diffusively expressed, 10 cases expressed CD56, 8 cases expressed p63, 6 cases expressed weakly punctated chromograin-A (CgA), and S-100 was not expressed. The Ki-67 index ranges from 20 to 90 percent. By the end of follow-up (0.5 to 127.0 months), 3 patients were alive, and the mean progression-free survival (21.0 months) of postoperative chemoradiotherapy patients was significantly longer than that of surgery and/or chemotherapy alone (3.3 months). Conclusions: Maxillofacial neuroendocrine carcinoma is characterized by low differentiation of small cells, high degree of malignancy and poor prognosis. Radical surgery combined with chemoradiotherapy has better local control effect.

Measurement of the ν_{e}-Nucleus Charged-Current Double-Differential Cross Section at ⟨E_{ν}⟩=2.4 GeV Using NOvA

The inclusive electron neutrino charged-current cross section is measured in the NOvA near detector using 8.02×10^{20} protons-on-target in the NuMI beam. The sample of GeV electron neutrino interactions is the largest analyzed to date and is limited by ≃17% systematic rather than the ≃7.4% statistical uncertainties. The double-differential cross section in final-state electron energy and angle is presented for the first time, together with the single-differential dependence on Q^{2} (squared four-momentum transfer) and energy, in the range 1  GeV≤E_{ν}<6  GeV. Detailed comparisons are made to the predictions of the GENIE, GiBUU, NEUT, and NuWro neutrino event generators. The data do not strongly favor a model over the others consistently across all three cross sections measured, though some models have especially good or poor agreement in the single differential cross section vs Q^{2}.

Glucocorticoid induced bone disorders in children: Research progress in treatment mechanisms

Long-term or supra-physiological dose of glucocorticoid (GC) application in clinic can lead to impaired bone growth and osteoporosis. The side effects of GC on the skeletal system are particularly serious in growing children, potentially causing growth retardation or even osteoporotic fractures. Children's bone growth is dependent on endochondral ossification of growth plate chondrocytes, and excessive GC can hinder the development of growth plate and longitudinal bone growth. Despite the availability of drugs for treating osteoporosis, they have failed to effectively prevent or treat longitudinal bone growth and development disorders caused by GCs. As of now, there is no specific drug to mitigate these severe side effects. Traditional Chinese Medicine shows potential as an alternative to the current treatments by eliminating the side effects of GC. In summary, this article comprehensively reviews the research frontiers concerning growth and development disorders resulting from supra-physiological levels of GC and discusses the future research and treatment directions for optimizing steroid therapy. This article may also provide theoretical and experimental insight into the research and development of novel drugs to prevent GC-related side effects.

A bioactive compliant vascular graft modulates macrophage polarization and maintains patency with robust vascular remodeling

Conventional synthetic vascular grafts are associated with significant failure rates due to their mismatched mechanical properties with the native vessel and poor regenerative potential. Though different tissue engineering approaches have been used to improve the biocompatibility of synthetic vascular grafts, it is still crucial to develop a new generation of synthetic grafts that can match the dynamics of native vessel and direct the host response to achieve robust vascular regeneration. The size of pores within implanted biomaterials has shown significant effects on macrophage polarization, which has been further confirmed as necessary for efficient vascular formation and remodeling. Here, we developed biodegradable, autoclavable synthetic vascular grafts from a new polyurethane elastomer and tailored the grafts' interconnected pore sizes to promote macrophage populations with a pro-regenerative phenotype and improve vascular regeneration and patency rate. The synthetic vascular grafts showed similar mechanical properties to native blood vessels, encouraged macrophage populations with varying M2 to M1 phenotypic expression, and maintained patency and vascular regeneration in a one-month rat carotid interposition model and in a four-month rat aortic interposition model. This innovative bioactive synthetic vascular graft holds promise to treat clinical vascular diseases.

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Small diameter vascular grafts were fabricated from a new elastomeric polyurethane designed for vascular tissue engineering.

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The grafts combined excellent elasticity, strength, porosity, hemocompatibility, degradability, and biocompatibility.

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In vivo, grafts maintained patency for four months and supported tissue regeneration resembling the native arterial wall.

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Pore size was found to influence graft characteristics and efficacy.

CCL2 promotes proliferation, migration and angiogenesis through the MAPK/ERK1/2/MMP9, PI3K/AKT, Wnt/β‑catenin signaling pathways in HUVECs

Severe bone trauma can lead to poor or delayed bone healing and nonunion. Bone regeneration is based on the interaction between osteogenesis and angiogenesis. Angiogenesis serves a unique role in the repair and remodeling of bone defects. Monocyte chemoattractant protein-1, also known as CC motif ligand 2 (CCL2), is a member of the CC motif chemokine family and was the first human chemokine to be revealed to be an effective chemokine of monocytes. However, its underlying mechanism in angiogenesis of bone defect repair remains to be elucidated. Therefore, the present study investigated the detailed mechanism by which CCL2 promoted angiogenesis in bone defects based on cell and animal model experiments. In the present study, CCL2 promoted proliferation, migration and tube formation in human umbilical vein endothelial cells (HUVECs) in a concentration-dependent manner. Western blot analysis revealed that treatment of HUVECs with CCL2 upregulated the protein expression levels of rho-associated coiled-coil-containing protein kinase (Rock)1, Rock2, N-cadherin, c-Myc and VEGFR2. Furthermore, CCL2 promoted the expression of MAPK/ERK1/2/MMP9, PI3K/AKT and Wnt/β-catenin signaling pathway-related proteins, which also demonstrated that CCL2 promoted these functions in HUVECs. Immunohistochemical staining of Sprague Dawley rat femurs following bone defects revealed that VEGF expression was positive in the newly formed bone area in each group, while the expression area of VEGF in the CCL2 addition group was markedly increased. Therefore, CCL2 is a potential therapeutic approach for bone defect repair and reconstruction through the mechanism of angiogenesis-osteogenesis coupling.

Growth and differentiation factor-7 immobilized, mechanically strong quadrol-hexamethylene diisocyanate-methacrylic anhydride polyurethane polymer for tendon repair and regeneration

Biological and mechanical cues are both vital for biomaterial aided tendon repair and regeneration. Here, we fabricated mechanically tendon-like (0 s UV) QHM polyurethane scaffolds (Q: Quadrol, H: Hexamethylene diisocyanate; M: Methacrylic anhydride) and immobilized them with Growth and differentiation factor-7 (GDF-7) to produce mechanically strong and tenogenic scaffolds. In this study, we assessed QHM polymer cytocompatibility, amenability to fibrin-coating, immobilization and persistence of GDF-7, and capability to support GDF-7-mediated tendon differentiation in vitro as well as in vivo in mouse subcutaneous and acute rat rotator cuff tendon resection models. Cytocompatibility studies showed that QHM facilitated cell attachment, proliferation, and viability. Fibrin-coating and GDF-7 retention studies showed that mechanically tendon-like 0 s UV QHM polymer could be immobilized with GDF-7 and retained the growth factor (GF) for at least 1-week ex vivo. In vitro differentiation studies showed that GDF-7 mediated bone marrow-derived human mesenchymal stem cell (hMSC) tendon-like differentiation on 0 s UV QHM. Subcutaneous implantation of GDF-7-immobilized, fibrin-coated, QHM polymer in mice for 2 weeks demonstrated de novo formation of tendon-like tissue while implantation of GDF-7-immobilized, fibrin-coated, QHM polymer in a rat acute rotator cuff resection injury model indicated tendon-like tissue formation in situ and the absence of heterotopic ossification. Together, our work demonstrates a promising synthetic scaffold with human tendon-like biomechanical attributes as well as immobilized tenogenic GDF-7 for tendon repair and regeneration. STATEMENT OF SIGNIFICANCE: Biological activity and mechanical robustness are key features required for tendon-promoting biomaterials. While synthetic biomaterials can be mechanically robust, they often lack bioactivity. To biologically augment synthetic biomaterials, numerous drug and GF delivery strategies exist but the large tissue space within the shoulder is constantly flushed with saline during arthroscopic surgery, hindering efficacious controlled release of therapeutic molecules. Here, we coated QHM polymer (which exhibits human tendon-to-bone-like biomechanical attributes) with fibrin for GF binding. Unlike conventional drug delivery strategies, our approach utilizes immobilized GFs as opposed to released GFs for sustained, localized tissue regeneration. Our data demonstrated that GF immobilization can be broadly applied to synthetic biomaterials for enhancing bioactivity, and GDF-7-immobilized QHM exhibit high clinical translational potential for tendon repair.

Enhancing cartilage repair with optimized supramolecular hydrogel-based scaffold and pulsed electromagnetic field

Functional tissue engineering strategies provide innovative approach for the repair and regeneration of damaged cartilage. Hydrogel is widely used because it could provide rapid defect filling and proper structure support, and is biocompatible for cell aggregation and matrix deposition. Efforts have been made to seek suitable scaffolds for cartilage tissue engineering. Here Alg-DA/Ac-β-CD/gelatin hydrogel was designed with the features of physical and chemical multiple crosslinking and self-healing properties. Gelation time, swelling ratio, biodegradability and biocompatibility of the hydrogels were systematically characterized, and the injectable self-healing adhesive hydrogel were demonstrated to exhibit ideal properties for cartilage repair. Furthermore, the new hydrogel design introduces a pre-gel state before photo-crosslinking, where increased viscosity and decreased fluidity allow the gel to remain in a semi-solid condition. This granted multiple administration routes to the hydrogels, which brings hydrogels the ability to adapt to complex clinical situations. Pulsed electromagnetic fields (PEMF) have been recognized as a promising solution to various health problems owing to their noninvasive properties and therapeutic potentials. PEMF treatment offers a better clinical outcome with fewer, if any, side effects, and wildly used in musculoskeletal tissue repair. Thereby we propose PEMF as an effective biophysical stimulation to be 4th key element in cartilage tissue engineering. In this study, the as-prepared Alg-DA/Ac-β-CD/gelatin hydrogels were utilized in the rat osteochondral defect model, and the potential application of PEMF in cartilage tissue engineering were investigated. PEMF treatment were proven to enhance the quality of engineered chondrogenic constructs in vitro, and facilitate chondrogenesis and cartilage repair in vivo. All of the results suggested that with the injectable self-healing adhesive hydrogel and PEMF treatment, this newly proposed tissue engineering strategy revealed superior clinical potential for cartilage defect treatment.

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The supramolecular Alg-DA/Ac-β-CD/gelatin hydrogel with physical and chemical multiple crosslinking was fabricated.

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The multi-crosslinked structure of the hydrogels endows strong injection, adhesion abilities and mechanical performance.

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A pre-gel state of the hydrogel grants it more administration routes and ability to adapt to complex clinical scenarios.

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Pulsed electromagnetic field (PEMF) serves as the 4^th element in mesenchymal stem cell-based cartilage tissue engineering.

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Bioinformatics analysis reveal that PEMF regulates chondrogenesis and cell hypertrophy via ERK and p38 MAPK pathways.

Bioactive Scaffold Fabricated by 3D Printing for Enhancing Osteoporotic Bone Regeneration

We develop a poly (lactic-co-glycolic acid)/β-calcium phosphate (PLGA/TCP)-based scaffold through a three-dimensional (3D) printing technique incorporating icaritin (ICT), a unique phytomolecule, and secretome derived from human fetal mesenchymal stem cells (HFS), to provide mechanical support and biological cues for stimulating bone defect healing. With the sustained release of ICT and HFS from the composite scaffold, the cell-free scaffold efficiently facilitates the migration of MSCs and promotes bone regeneration at the femoral defect site in the ovariectomy (OVX)-induced osteoporotic rat model. Furthermore, mechanism study results indicate that the combination of ICT and HFS additively activates the Integrin-FAK (focal adhesion kinase)-ERK1/2 (extracellular signal-regulated kinase 1/2)-Runx2 (Runt-related transcription factor 2) axis, which could be linked to the beneficial recruitment of MSCs to the implant and subsequent osteogenesis enhancement. Collectively, the PLGA/TCP/ICT/HFS (P/T/I/S) bioactive scaffold is a promising biomaterial for repairing osteoporotic bone defects, which may have immense implications for their translation to clinical practice.

Impacts of menopause hormone therapy on mood disorders among postmenopausal women

OBJECTIVE

This study aimed to explore the modulatory effects of menopause hormone therapy (MHT) on mood disorders among postmenopausal women.

METHODS

A cross-sectional study was conducted to recruit postmenopausal women, including patients (arranged MHT for over 3 years as the medication group) and non-MHT controls. All participants were asked to respond to the Center for Epidemiological Studies Depression Scale (CES-D) and Generalized Anxiety Disorder Screener (GAD-7) questionnaires to assess their depression and anxiety status.

RESULTS

A total of 230 cases from the two groups were determined based on propensity score matching analysis by matching the menopausal age and menopausal durations. We found that MHT served as a favorable modulator in the depression status of postmenopausal women. Among the four factors of the CES-D questionnaire, our data indicated that the differences between the two groups fell primarily into two aspects: depressive emotion, and somatic symptoms or retarded activities. MHT was mainly involved in improving the depression of overweight women. However, no substantial effects of MHT were observed on the regulation of anxiety.

CONCLUSION

Postmenopausal women, especially the overweight population, who have experienced MHT exhibited an improved depressive status but not their anxiety condition.

Lipid Metabolism in Cartilage Development, Degeneration, and Regeneration

Lipids affect cartilage growth, injury, and regeneration in diverse ways. Diet and metabolism have become increasingly important as the prevalence of obesity has risen. Proper lipid supplementation in the diet contributes to the preservation of cartilage function, whereas excessive lipid buildup is detrimental to cartilage. Lipid metabolic pathways can generate proinflammatory substances that are crucial to the development and management of osteoarthritis (OA). Lipid metabolism is a complicated metabolic process involving several regulatory systems, and lipid metabolites influence different features of cartilage. In this review, we examine the current knowledge about cartilage growth, degeneration, and regeneration processes, as well as the most recent research on the significance of lipids and their metabolism in cartilage, including the extracellular matrix and chondrocytes. An in-depth examination of the involvement of lipid metabolism in cartilage metabolism will provide insight into cartilage metabolism and lead to the development of new treatment techniques for metabolic cartilage damage.

Exosome-based strategy for degenerative disease in orthopedics: Recent progress and perspectives

BACKGROUND

Degenerative diseases in orthopaedics have become a significant global public health issue with the aging of the population worldwide. The traditional medical interventions, including physical therapy, pharmacological therapy and even surgery, hardly work to modify degenerative progression. Stem cell-based therapy is widely accepted to treat degenerative orthopaedic disease effectively but possesses several limitations, such as the need for strict monitoring of production and storage and the potential risks of tumorigenicity and immune rejection in clinical translation. Furthermore, the ethical issues surrounding the acquisition of embryonic stem cells are also broadly concerned. Exosome-based therapy has rapidly grown in popularity in recent years and is regarded as an ideal alternative to stem cell-based therapy, offering a promise to achieve 'cell-free' tissue regeneration.

METHODS

Traditionally, the native exosomes extracted from stem cells are directly injected into the injured site to promote tissue regeneration. Recently, several modified exosome-based strategies were developed to overcome the limitations of native exosomes, which include mainly exogenous molecule loading and exosome delivery through scaffolds. In this paper, a systematic review of the exosome-based strategy for degenerative disease in orthopaedics is presented.

RESULTS

Treatment strategies based on the native exosomes are effective but with several disadvantages such as rapid diffusion and insufficient and fluctuating functional contents. The modified exosome-based strategies can better match the requirements of the regeneration in some complex healing processes.

CONCLUSION

Exosome-based strategies hold promise to manage degenerative disease in orthopaedics prior to patients reaching the advanced stage of disease in the future. The timely summary and highlights offered herein could provide a research perspective to promote the development of exosome-based therapy, facilitating the clinical translation of exosomes in orthopaedics.

TRANSLATIONAL POTENTIAL OF THIS ARTICLE

Exosome-based therapy is superior in anti-senescence and anti-inflammatory effects and possesses lower risks of tumorigenicity and immune rejection relative to stem cell-based therapy. Exosome-based therapy is regarded as an ideal alternative to stem cell-based therapy, offering a promise to achieve 'cell-free' tissue regeneration.

Dual Delivery of BMP2 and IGF1 Through Injectable Hydrogel Promotes Cranial Bone Defect Healing

Critical-sized cranial bone defect remains a great clinical challenge. With advantages in regenerative medicine, injectable hydrogels incorporated with bioactive molecules show great potential in promoting cranial bone repair. Recently, we developed a dual delivery system by sequential release of bone morphogenetic protein 2 (BMP2) followed by insulin-like growth factor 1 (IGF1) in microparticles (MPs), and an injectable alginate/collagen (alg/col)-based hydrogel. In this study, we aim to evaluate the effect of dual delivery of BMP2 and IGF1 in MPs through the injectable hydrogel in critical-sized cranial bone defect healing. The gelatin MPs loaded with BMP2 and poly(lactic-co-glycolic acid)-poly(ethylene glycol)-carboxyl (PLGA-PEG-COOH) MPs loaded with IGF1 were prepared, respectively. The encapsulation efficiency and release profile of growth factors in MPs were measured. A cranial defect model was applied to evaluate the efficacy of the dual delivery system in bone regeneration. Adult Sprague Dawley rats were subjected to osteotomy to make an ⌀8-mm cranial defect. The injectable hydrogel containing MPs loaded with BMP2 (2 μg), IGF1 (2 μg), or a combination of BMP2 (1 μg) and IGF1 (1 μg) were injected to the defect site. New bone formation was evaluated by microcomputed tomography, histological analysis, and immunohistochemistry after 4 or 8 weeks. Data showed that dual delivery of the low-dose BMP2 and IGF1 in MPs through alg/col-based hydrogel successfully restored cranial bone as early as 4 weeks after implantation, whose effect was comparable to the single delivery of high-dose BMP2 in MPs. In conclusion, this study suggests that dual delivery of BMP2 and IGF1 in MPs in alg/col-based hydrogel achieves early bone regeneration in critical-sized bone defect, with advantage in reducing the dose of BMP2. Impact Statement Sequential release of bone morphogenetic protein 2 (BMP2) followed by insulin-like growth factor 1 (IGF1) in two different microparticles promotes critical-sized bone defect healing. This dual delivery system reduces the dose of BMP2 by supplementing IGF1, which may diminish the potential side effects of BMP2.

First Measurement of High-Energy Reactor Antineutrinos at Daya Bay

This Letter reports the first measurement of high-energy reactor antineutrinos at Daya Bay, with nearly 9000 inverse beta decay candidates in the prompt energy region of 8-12 MeV observed over 1958 days of data collection. A multivariate analysis is used to separate 2500 signal events from background statistically. The hypothesis of no reactor antineutrinos with neutrino energy above 10 MeV is rejected with a significance of 6.2 standard deviations. A 29% antineutrino flux deficit in the prompt energy region of 8-11 MeV is observed compared to a recent model prediction. We provide the unfolded antineutrino spectrum above 7 MeV as a data-based reference for other experiments. This result provides the first direct observation of the production of antineutrinos from several high-Q_{β} isotopes in commercial reactors.

Scintillation light detection in the 6-m drift-length ProtoDUNE Dual Phase liquid argon TPC

DUNE is a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon decay searches. ProtoDUNE Dual Phase (DP) is a 6  ×  6  ×  6 m 3 liquid argon time-projection-chamber (LArTPC) that recorded cosmic-muon data at the CERN Neutrino Platform in 2019-2020 as a prototype of the DUNE Far Detector. Charged particles propagating through the LArTPC produce ionization and scintillation light. The scintillation light signal in these detectors can provide the trigger for non-beam events. In addition, it adds precise timing capabilities and improves the calorimetry measurements. In ProtoDUNE-DP, scintillation and electroluminescence light produced by cosmic muons in the LArTPC is collected by photomultiplier tubes placed up to 7 m away from the ionizing track. In this paper, the ProtoDUNE-DP photon detection system performance is evaluated with a particular focus on the different wavelength shifters, such as PEN and TPB, and the use of Xe-doped LAr, considering its future use in giant LArTPCs. The scintillation light production and propagation processes are analyzed and a comparison of simulation to data is performed, improving understanding of the liquid argon properties.

Human fetal mesenchymal stem cells secretome promotes scarless diabetic wound healing through heat-shock protein family

The high mortality rate of patients with diabetic foot ulcers is urging the appearance of an effective biomedical drug. Senescence is one of the major reasons of aging-induced decline in the diabetic wound. Our previous studies have demonstrated the anti-senescence effect of secretomes derived from human fetal mesenchymal stem cells (hfMSC). The present study tends to explore the potential role of hfMSC secretome (HFS) in wound healing through anti-aging. Meanwhile, we try to overcome several obstacles in the clinical application of stem cell secretome. A verticle bioreactor and microcarriers are employed to expand hfMSC and produce the HFS on a large scale. The HFS was then subjected to lyophilization (L-HFS). The PLGA (poly lactic-co-glycolic acid) particles were used to encapsulate and protect L-HFS from degradation in the streptozotocin (STZ)-induced diabetic rat model. Results showed that HFS-PLGA significantly enhanced wound healing by promoting vascularization and inhibiting inflammation in the skin wound bed. We further analyzed the contents of HFS. Isobaric tag for relative and absolute quantitation (ITRAQ) and label-free methods were used to identify peptides in the secretome. Bioinformatics analysis indicated that exosome production-related singling pathways and heat-shock protein family could be used as bio-functional markers and quality control for stem cell secretome production.