Enhanced osteochondral regeneration with a 3D-Printed biomimetic scaffold featuring a calcified interfacial layer

The integrative regeneration of both articular cartilage and subchondral bone remains an unmet clinical need due to the difficulties of mimicking spatial complexity in native osteochondral tissues for artificial implants. Layer-by-layer fabrication strategies, such as 3D printing, have emerged as a promising technology replicating the stratified zonal architecture and varying microstructures and mechanical properties. However, the dynamic and circulating physiological environments, such as mass transportation or cell migration, usually distort the pre-confined biological properties in the layered implants, leading to undistinguished spatial variations and subsequently inefficient regenerations. This study introduced a biomimetic calcified interfacial layer into the scaffold as a compact barrier between a cartilage layer and a subchondral bone layer to facilitate osteogenic-chondrogenic repair. The calcified interfacial layer consisting of compact polycaprolactone (PCL), nano-hydroxyapatite, and tasquinimod (TA) can physically and biologically separate the cartilage layer (TA-mixed, chondrocytes-load gelatin methacrylate) from the subchondral bond layer (porous PCL). This introduction preserved the as-designed independent biological environment in each layer for both cartilage and bone regeneration, successfully inhibiting vascular invasion into the cartilage layer and preventing hyaluronic cartilage calcification owing to devascularization of TA. The improved integrative regeneration of cartilage and subchondral bone was validated through gross examination, micro-computed tomography (micro-CT), and histological and immunohistochemical analyses based on an in vivo rat model. Moreover, gene and protein expression studies identified a key role of Caveolin (CAV-1) in promoting angiogenesis through the Wnt/β-catenin pathway and indicated that TA in the calcified layer blocked angiogenesis by inhibiting CAV-1.

Oncogenic Fatty Acid Metabolism Rewires Energy Supply Chain in Gastric Carcinogenesis

BACKGROUND & AIMS

Gastric carcinogenesis develops within a sequential carcinogenic cascade from precancerous metaplasia to dysplasia and adenocarcinoma, and oncogenic gene activation can drive the process. Metabolic reprogramming is considered a key mechanism for cancer cell growth and proliferation. However, how metabolic changes contribute to the progression of metaplasia to dysplasia remains unclear. We have examined metabolic dynamics during gastric carcinogenesis using a novel mouse model that induces Kras activation in zymogen-secreting chief cells.

METHODS

We generated a Gif-rtTA;TetO-Cre;KrasG12D (GCK) mouse model that continuously induces active Kras expression in chief cells after doxycycline treatment. Histologic examination and imaging mass spectrometry were performed in the GCK mouse stomachs at 2 to 14 weeks after doxycycline treatment. Mouse and human gastric organoids were used for metabolic enzyme inhibitor treatment. The GCK mice were treated with a stearoyl- coenzyme A desaturase (SCD) inhibitor to inhibit the fatty acid desaturation. Tissue microarrays were used to assess the SCD expression in human gastrointestinal cancers.

RESULTS

The GCK mice developed metaplasia and high-grade dysplasia within 4 months. Metabolic reprogramming from glycolysis to fatty acid metabolism occurred during metaplasia progression to dysplasia. Altered fatty acid desaturation through SCD produces a novel eicosenoic acid, which fuels dysplastic cell hyperproliferation and survival. The SCD inhibitor killed both mouse and human dysplastic organoids and selectively targeted dysplastic cells in vivo. SCD was up-regulated during carcinogenesis in human gastrointestinal cancers.

CONCLUSIONS

Active Kras expression only in gastric chief cells drives the full spectrum of gastric carcinogenesis. Also, oncogenic metabolic rewiring is an essential adaptation for high-energy demand in dysplastic cells.

Ferroptosis is involved in trophoblast cells cytotoxicity induced by black phosphorus nanoparticles

Black phosphorus (BP) is a new type of nanomaterial, which has been widely used in many biomedical fields due to its superior properties, but there are few studies on the toxicity of BP, especially in the reproductive system. To explore the effects of BP exposure on reproduction and reveal its molecular mechanism, we firstly investigated the potential toxicity of black phosphorus nanoparticles (BPNPs) in vivo. The results showed that BP exposure in pregnant mice can reduce the weight of fetal mice and placenta. H&E staining further indicated the changes of placental cross-section and vascular remodeling after BP treatment. Then, human exvillous trophoblast HTR8/SVneo was treated with different concentrations of BPNPs. We found that BPNPs induced significant cytotoxicity, including dose-dependent reduction of cell viability and proliferation. Trophoblast cell migration and invasion were also impaired by BPNPs exposure. Moreover, pretreatment with Cytochalasin D (Cyto-D), a classical phagocytic inhibitor, alleviated the decline of cell viability induced by BPNPs. Transcriptome sequencing showed that BPNPs exposure led to ferroptosis. Subsequently, the related indexes of ferroptosis were detected, including increase of iron ion concentration, decrease of the ferroptosis marker, GPX4 (Glutathione Peroxidase 4), increase of FTL (Ferritin Light Chain), and increase of lipid peroxidation indexes (MDA level and decrease of GSH level). In addition, ferroptosis inhibitors (Fer-1 and DFO) pretreatment can alleviate both the cytotoxic effects and functional impairment induced by BPNPs. In summary, our study confirmed the reproductive toxicity of BPNPs for the first time, and constructed BPNPs injury model in vitro using human villus trophoblast cells and revealed the role of ferroptosis in this process, which deepened our understanding of the biosafety of black phosphorus nanomaterials.

Development of a risk-predicting score for hip preservation with bone grafting therapy for osteonecrosis

Identification and differentiation of appropriate indications on hip preserving with bone grafting therapy remains a crucial challenge in the treatment of osteonecrosis of the femoral head (ONFH). A prospective cohort study on bone grafting therapy for ONFH aimed to evaluate hip survival rates, and to establish a risk scoring derived from potential risk factors (multivariable model) for hip preservation. Eight variables were identified to be strongly correlated with a decreased rate of hip survival post-therapy, and a comprehensive risk scoring was developed for predicting hip-preservation outcomes. The C-index stood at 0.72, and the areas under the receiver operating characteristics for the risk score's 5- and 10-year hip failure event predictions were 0.74 and 0.72, respectively. This risk score outperforms conventional methods in forecasting hip preservation. Bone grafting shows sustained benefits in treating ONFH when applied under the right indications. Furthermore, the risk scoring proves valuable as a decision-making tool, facilitating risk stratification for ONFH treatments in future.

Preferential cleavage of upstream targets in concatenated miRNA/siRNA target sites support a 5'-3' scanning model for RISC target recognition

RNA interference (RNAi) is becoming medicine for curing human diseases. Still, we lack a thorough understanding of some fundamental aspects of RNAi that affect its efficiency and accuracy. One such question is how RNA-induced silencing complex (RISC) can efficiently find its targets. To address this question, we developed a strategy that involves the expression of mRNAs containing concatenations of identical miRNA/siRNA target sites. These mRNAs were cleaved by co-expressed miRNAs in plant cells or by co-transfected siRNAs in mammalian cells. The mRNA cleavage events were then detected using the 5'RACE assay. Using this strategy, we found that RISCs preferentially cleave the upstream ones of concatenated target sites, consistent with a model that RISC scans mRNA in 5'→3' direction to approach its target sites. The stability of the cleaved mRNA fragments correlates with the complementarity between siRNA and its target sequence. When siRNA perfectly complements its target sequence, the cleaved mRNA fragment becomes stable and may be cleaved in a second round. Our findings have practical implications for designing siRNAs with increased efficiency and reduced off-target effects.

Physiological and transcriptomic comparisons shed light on the cold stress response mechanisms of Dendrobium spp

BACKGROUND

Dendrobium spp. comprise a group of tropical orchids with ornamental and medicinal value. Dendrobium spp. are sensitive to low temperature, and the underlying cold response regulatory mechanisms in this group are unclear. To understand how these plants respond to cold stress, we compared the transcriptomic responses of the cold-tolerant cultivar 'Hongxing' (HX) and the cold-sensitive cultivar 'Sonia Hiasakul' (SH) to cold stress.

RESULTS

Chemometric results showed that the physiological response of SH in the later stages of cold stress is similar to that of HX throughout the cold treatment. Orthogonal partial least squares discriminant analysis (OPLS-DA) revealed that soluble protein content and peroxidase activity are key physiological parameters for assessing the cold tolerance of these two Dendrobium spp. cultivars. Additionally, weighted gene co-expression network analysis (WGCNA) results showed that many cold response genes and metabolic pathways significantly associated with the physiological indices were enriched in the 12 detected modules. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and gene ontology (GO) enrichment analyses of the 105 hub genes showed that Dendrobium spp. adapt to cold stress by regulating signal transduction, phytohormones, transcription factors, protein translation and modification, functional proteins, biosynthesis and metabolism, cell structure, light, and the circadian clock. Hub genes of the cold stress response network included the remorin gene pp34, the abscisic acid signaling pathway-related genes PROTEIN PHOSPATASE 2 C (PP2C), SNF1-RELATED PROTEIN KINASE 2 (SnRK2), ABRE-BINDING FACTOR 1 (ABF1) and SKI-INTERACTING PROTEIN 17 (SKIP17), the Ca2+ signaling-related GTP diphosphokinase gene CRSH1, the carbohydrate-related gene STARCH SYNTHASE 2 (SS2), the cell wall biosynthesis gene CINNAMYL ALCOHOL DEHYDROGENASE (CAD7), and the endocytosis-related gene VACUOLAR PROTEIN SORTING-ASSOCIATED PROTEIN 52 A (VPS52A).

CONCLUSIONS

The cold-responsive genes and metabolic pathways of Dendrobium spp. revealed in this study provide important insight to enable the genetic enhancement of cold tolerance in Dendrobium spp., and to facilitate cold tolerance breeding in related plants.

Semantic Invariant Multi-View Clustering With Fully Incomplete Information

Robust multi-view learning with incomplete information has received significant attention due to issues such as incomplete correspondences and incomplete instances that commonly affect real-world multi-view applications. Existing approaches heavily rely on paired samples to realign or impute defective ones, but such preconditions cannot always be satisfied in practice due to the complexity of data collection and transmission. To address this problem, we present a novel framework called SeMantic Invariance LEarning (SMILE) for multi-view clustering with incomplete information that does not require any paired samples. To be specific, we discover the existence of invariant semantic distribution across different views, which enables SMILE to alleviate the cross-view discrepancy to learn consensus semantics without requiring any paired samples. The resulting consensus semantics remains unaffected by cross-view distribution shifts, making them useful for realigning/imputing defective instances and forming clusters. We demonstrate the effectiveness of SMILE through extensive comparison experiments with 13 state-of-the-art baselines on five benchmarks. Our approach improves the clustering accuracy of NoisyMNIST from 19.3%/23.2% to 82.7%/69.0% when the correspondences/instances are fully incomplete. We will release the code after acceptance.

Pcgf5: An important regulatory factor in early embryonic neural induction

Polycomb group RING finger (PCGF) proteins, a crucial subunits of the Polycomb complex, plays an important role in regulating gene expression, embryonic development, and cell fate determination. In our research, we investigated Pcgf5, one of the six PCGF homologs, and its impact on the differentiation of P19 cells into neural stem cells. Our findings revealed that knockdown of Pcgf5 resulted in a significant decrease in the expression levels of the neuronal markers Sox2, Zfp521, and Pax6, while the expression levels of the pluripotent markers Oct4 and Nanog increased. Conversely, Pcgf5 overexpression upregulated the expression of Sox2 and Pax6, while downregulating the expression of Oct4 and Nanog. Additionally, our analysis revealed that Pcgf5 suppresses Wnt3 expression via the activation of Notch1/Hes1, and ultimately governs the differentiation fate of neural stem cells. To further validate our findings, we conducted in vivo experiments in zebrafish. We found that knockdown of pcgf5a using morpholino resulted in the downregulated expression of neurodevelopmental genes such as sox2, sox3, and foxg1 in zebrafish embryos. Consequently, these changes led to neurodevelopmental defects. In conclusion, our study highlights the important role of Pcgf5 in neural induction and the determination of neural cell fate.

Osteocyte mitochondria regulate angiogenesis of transcortical vessels

Transcortical vessels (TCVs) provide effective communication between bone marrow vascular system and external circulation. Although osteocytes are in close contact with them, it is not clear whether osteocytes regulate the homeostasis of TCVs. Here, we show that osteocytes maintain the normal network of TCVs by transferring mitochondria to the endothelial cells of TCV. Partial ablation of osteocytes causes TCV regression. Inhibition of mitochondrial transfer by conditional knockout of Rhot1 in osteocytes also leads to regression of the TCV network. By contrast, acquisition of osteocyte mitochondria by endothelial cells efficiently restores endothelial dysfunction. Administration of osteocyte mitochondria resultes in acceleration of the angiogenesis and healing of the cortical bone defect. Our results provide new insights into osteocyte-TCV interactions and inspire the potential application of mitochondrial therapy for bone-related diseases.

Enhanced articular cartilage regeneration using costal chondrocyte-derived scaffold-free tissue engineered constructs with ascorbic acid treatment

Background

Cartilage tissue engineering faces challenges related to the use of scaffolds and limited seed cells. This study aims to propose a cost-effective and straightforward approach using costal chondrocytes (CCs) as an alternative cell source to overcome these challenges, eliminating the need for special culture equipment or scaffolds.

Methods

CCs were cultured at a high cell density with and without ascorbic acid treatment, serving as the experimental and control groups, respectively. Viability and tissue-engineered constructs (TEC) formation were evaluated until day 14. Slices of TEC samples were used for histological staining to evaluate the secretion of glycosaminoglycans and different types of collagen proteins within the extracellular matrix. mRNA sequencing and qPCR were performed to examine gene expression related to cartilage matrix secretion in the chondrocytes. In vivo experiments were conducted by implanting TECs from different groups into the defect site, followed by sample collection after 12 weeks for histological staining and scoring to evaluate the extent of cartilage regeneration. Hematoxylin-eosin (HE), Safranin-O-Fast Green, and Masson's trichrome stainings were used to examine the content of cartilage-related matrix components in the in vivo repair tissue. Immunohistochemical staining for type I and type II collagen, as well as aggrecan, was performed to assess the presence and distribution of these specific markers. Additionally, immunohistochemical staining for type X collagen was used to observe any hypertrophic changes in the repaired tissue.

Results

Viability of the chondrocytes remained high throughout the culture period, and the TECs displayed an enriched extracellular matrix suitable for surgical procedures. In vitro study revealed glycosaminoglycan and type II collagen production in both groups of TEC, while the TEC matrix treated with ascorbic acid displayed greater abundance. The results of mRNA sequencing and qPCR showed that genes related to cartilage matrix secretion such as Sox9, Col2, and Acan were upregulated by ascorbic acid in costal chondrocytes. Although the addition of Asc-2P led to an increase in COL10 expression according to qPCR and RNA-seq results, the immunofluorescence staining results of the two groups of TECs exhibited similar distribution and fluorescence intensity. In vivo experiments showed that both groups of TEC could adhere to the defect sites and kept hyaline cartilage morphology until 12 weeks. TEC treated with ascorbic acid showed superior cartilage regeneration as evidenced by significantly higher ICRS and O'Driscoll scores and stronger Safranin-O and collagen staining mimicking native cartilage when compared to other groups. In addition, the immunohistochemical staining results of Collgan X indicated that, after 12 weeks, the ascorbic acid-treated TEC did not exhibit further hypertrophy upon transplantation into the defect site, but maintained an expression profile similar to untreated TECs, while slightly higher than the sham-operated group.

Conclusion

These results suggest that CC-derived scaffold-free TEC presents a promising method for articular cartilage regeneration. Ascorbic acid treatment enhances outcomes by promoting cartilage matrix production. This study provides valuable insights and potential advancements in the field of cartilage tissue engineering.

The translational potential of this article

Cartilage tissue engineering is an area of research with immense clinical potential. The approach presented in this article offers a cost-effective and straightforward solution, which can minimize the complexity of cell culture and scaffold fabrication. This simplification could offer several translational advantages, such as ease of use, rapid scalability, lower costs, and the potential for patient-specific clinical translation. The use of costal chondrocytes, which are easily obtainable, and the scaffold-free approach, which does not require specialized equipment or membranes, could be particularly advantageous in clinical settings, allowing for in situ regeneration of cartilage.

Ferroptosis in Osteocytes as a Target for Protection Against Postmenopausal Osteoporosis

Ferroptosis is a necrotic form of iron-dependent regulatory cell death. Estrogen withdrawal can interfere with iron metabolism, which is responsible for the pathogenesis of postmenopausal osteoporosis (PMOP). Here, it is demonstrated that estrogen withdrawal induces iron accumulation in the skeleton and the ferroptosis of osteocytes, leading to reduced bone mineral density. Furthermore, the facilitatory effect of ferroptosis of osteocytes is verified in the occurrence and development of postmenopausal osteoporosis is associated with over activated osteoclastogenesis using a direct osteocyte/osteoclast coculture system and glutathione peroxidase 4 (GPX4) knockout ovariectomized mice. In addition, the nuclear factor erythroid derived 2-related factor-2 (Nrf2) signaling pathway is confirmed to be a crucial factor in the ferroptosis of osteocytic cells. Nrf2 regulates the expression of nuclear factor kappa-B ligand (RANKL) by regulating the DNA methylation level of the RANKL promoter mediated by DNA methyltransferase 3a (Dnmt3a), which is as an important mechanism in osteocytic ferroptosis-mediated osteoclastogenesis. Taken together, this data suggests that osteocytic ferroptosis is involved in PMOP and can be targeted to tune bone homeostasis.

Biomimetic Targeting Nanoadjuvants for Sonodynamic and Chronological Multi-Immunotherapy against Holistic Biofilm-Related Infections

Biofilm-related infections (BRIs) present significant challenges owing to drug resistance, adverse immune responses, and implant failure; however, current approaches inadequately cater to the diverse therapeutic requirements at different stages of infection. To address this issue, a multi-immunotherapy strategy in combination with sonodynamic therapy is proposed for the chronological treatment of BRIs. Macrophage membrane-decorated targeting sonosensitive nanoadjuvants are fabricated to load cytosine-phosphate-guanine oligodeoxynucleotide (CPG-ODN) or microRNA (miR)-21-5p. In the early stages of BRI (Stage I), CPG-ODN-loaded nanoadjuvants (CPG@HMPN@M) promote the formation of neutrophil extracellular traps to capture and neutralize detached microbes. During the late stage of infection (Stage II), CPG-ODNs redirect macrophage polarization into the M1 phase to combat infections via TLR9/Myd88/TRAF6 pathway. During these stages, CPG@HMPN@M generates singlet oxygen through sonodynamic processes, eradicating the biofilms under US irradiation. Once the BRIs are eliminated, miR-21-5p-loaded nanoadjuvants (miR@HMPN@M) are delivered to the lesions to suppress excessive inflammation and promote tissue integration by evoking macrophage M2 polarization during the repair phase (Stage III) through PTEN/PI3K/Akt pathway. This innovative approach aims to provide comprehensive treatment strategies for the chronological treatment of BRI by effectively eliminating infections, promoting tissue restoration, and implementing different immune regulations at different stages, thus demonstrating promising clinical value.

Pick-and-Place Transform Learning for Fast Multi-View Clustering

To manipulate large-scale data, anchor-based multi-view clustering methods have grown in popularity owing to their linear complexity in terms of the number of samples. However, these existing approaches pay less attention to two aspects. 1) They target at learning a shared affinity matrix by using the local information from every single view, yet ignoring the global information from all views, which may weaken the ability to capture complementary information. 2) They do not consider the removal of feature redundancy, which may affect the ability to depict the real sample relationships. To this end, we propose a novel fast multi-view clustering method via pick-and-place transform learning named PPTL, which could capture insightful global features to characterize the sample relationships quickly. Specifically, PPTL first concatenates all the views along the feature direction to produce a global matrix. Considering the redundancy of the global matrix, we design a pick-and-place transform with l2,p -norm regularization to abandon the poor features and consequently construct a compact global representation matrix. Thus, by conducting anchor-based subspace clustering on the compact global representation matrix, PPTL can learn a consensus skinny affinity matrix with a discriminative clustering structure. Numerous experiments performed on small-scale to large-scale datasets demonstrate that our method is not only faster but also achieves superior clustering performance over state-of-the-art methods across a majority of the datasets.

Autoencoder in Autoencoder Networks

Modeling complex correlations on multiview data is still challenging, especially for high-dimensional features with possible noise. To address this issue, we propose a novel unsupervised multiview representation learning (UMRL) algorithm, termed autoencoder in autoencoder networks (AE2-Nets). The proposed framework effectively encodes information from high-dimensional heterogeneous data into a compact and informative representation with the proposed bidirectional encoding strategy. Specifically, the proposed AE2-Nets conduct encoding in two directions: the inner-AE-networks extract view-specific intrinsic information (forward encoding), while the outer-AE-networks integrate this view-specific intrinsic information from different views into a latent representation (backward encoding). For the nested architecture, we further provide a probabilistic explanation and extension from hierarchical variational autoencoder. The forward-backward strategy flexibly addresses high-dimensional (noisy) features within each view and encodes complementarity across multiple views in a unified framework. Extensive results on benchmark datasets validate the advantages compared to the state-of-the-art algorithms.

Osteocyte mitochondria inhibit tumor development via STING-dependent antitumor immunity

Bone is one of the most common sites of tumor metastases. During the last step of bone metastasis, cancer cells colonize and disrupt the bone matrix, which is maintained mainly by osteocytes, the most abundant cells in the bone microenvironment. However, the role of osteocytes in bone metastasis is still unclear. Here, we demonstrated that osteocytes transfer mitochondria to metastatic cancer cells and trigger the cGAS/STING-mediated antitumor response. Blocking the transfer of mitochondria by specifically knocking out mitochondrial Rho GTPase 1 (Rhot1) or mitochondrial mitofusin 2 (Mfn2) in osteocytes impaired tumor immunogenicity and consequently resulted in the progression of metastatic cancer toward the bone matrix. These findings reveal the protective role of osteocytes against cancer metastasis by transferring mitochondria to cancer cells and potentially offer a valuable therapeutic strategy for preventing bone metastasis.

Targeting Stem Cells and Dysplastic Features With Dual MEK/ERK and STAT3 Suppression in Gastric Carcinogenesis

BACKGROUNDS & AIMS

Precancerous metaplasia progression to dysplasia can increase the risk of gastric cancers. However, effective strategies to specifically target these precancerous lesions are currently lacking. To address this, we aimed to identify key signaling pathways that are upregulated during metaplasia progression and critical for stem cell survival and function in dysplasia.

METHODS

To assess the response to chemotherapeutic drugs, we used metaplastic and dysplastic organoids derived from Mist1-Kras mice and 20 human precancerous organoid lines established from patients with gastric cancer. Phospho-antibody array analysis and single-cell RNA-sequencing were performed to identify target cell populations and signaling pathways affected by pyrvinium, a putative anticancer drug. Pyrvinium was administered to Mist1-Kras mice to evaluate drug effectiveness in vivo.

RESULTS

Although pyrvinium treatment resulted in growth arrest in metaplastic organoids, it induced cell death in dysplastic organoids. Pyrvinium treatment significantly downregulated phosphorylation of ERK and signal transducer and activator of transcription 3 (STAT3) as well as STAT3-target genes. Single-cell RNA-sequencing data analyses revealed that pyrvinium specifically targeted CD133+/CD166+ stem cell populations, as well as proliferating cells in dysplastic organoids. Pyrvinium inhibited metaplasia progression and facilitated the restoration of normal oxyntic glands in Mist1-Kras mice. Furthermore, pyrvinium exhibited suppressive effects on the growth and survival of human organoids with dysplastic features, through simultaneous blocking of the MEK/ERK and STAT3 signaling pathways.

CONCLUSIONS

Through its dual blockade of MEK/ERK and STAT3 signaling pathways, pyrvinium can effectively induce growth arrest in metaplasia and cell death in dysplasia. Therefore, our findings suggest that pyrvinium is a promising chemotherapeutic agent for reprogramming the precancerous milieu to prevent gastric cancer development.

H3K36 methyltransferase NSD1 protects against osteoarthritis through regulating chondrocyte differentiation and cartilage homeostasis

Osteoarthritis (OA) is one of the most common joint diseases, there are no effective disease-modifying drugs, and the pathological mechanisms of OA need further investigation. Here, we show that H3K36 methylations were decreased in senescent chondrocytes and age-related osteoarthritic cartilage. Prrx1-Cre inducible H3.3K36M transgenic mice showed articular cartilage destruction and osteophyte formation. Conditional knockout Nsd1Prrx1-Cre mice, but not Nsd2Prrx1-Cre or Setd2Prrx1-Cre mice, replicated the phenotype of K36M/+; Prrx1-Cre mice. Immunostaining results showed decreased anabolic and increased catabolic activities in Nsd1Prrx1-Cre mice, along with decreased chondrogenic differentiation. Transcriptome and ChIP-seq data revealed that Osr2 was a key factor affected by Nsd1. Intra-articular delivery of Osr2 adenovirus effectively improved the homeostasis of articular cartilage in Nsd1Prrx1-Cre mice. In human osteoarthritic cartilages, both mRNA and protein levels of NSD1 and OSR2 were decreased. Our results indicate that NSD1-induced H3K36 methylations and OSR2 expression play important roles in articular cartilage homeostasis and OA. Targeting H3K36 methylation and OSR2 would be a novel strategy for OA treatment.

Costal Cartilage Graft Repair Osteochondral Defect in a Mouse Model

OBJECTIVE

Osteochondral defects develop into osteoarthritis without intervention. Costal cartilage can be utilized as an alternative source for repairing osteochondral defect. Our previous clinical study has shown the successful osteochondral repair by costal cartilage graft with integration into host bone bed. In this study, we investigate how cartilaginous graft adapt to osteochondral environment and the mechanism of bone-cartilage interface formation.

DESIGN

Costal cartilage grafting was performed in C57BL/6J mice and full-thickness osteochondral defect was made as control. 3D optical profiles and micro-CT were applied to evaluate the reconstruction of articular cartilage surface and subchondral bone as well as gait analysis to evaluate articular function. Histological staining was performed at 2, 4, and 8 weeks after surgery. Moreover, costal cartilage from transgenic mice with fluorescent markers were transplanted into wild-type mice to observe the in vivo changes of costal chondrocytes.

RESULTS

At 8 weeks after surgery, 3D optical profiles and micro-CT showed that in the graft group, the articular surface and subchondral bone were well preserved. Gait analysis and International Cartilage Repair Society (ICRS) score evaluation showed a good recovery of joint function and histological repair in the graft group. Safranin O staining showed the gradual integration of graft and host tissue. Costal cartilage from transgenic mice with fluorescent markers showed that donor-derived costal chondrocytes turned into osteocytes in the subchondral area of host femur.

CONCLUSION

Costal cartilage grafting shows both functional and histological repair of osteochondral defect in mice. Graft-derived costal chondrocytes differentiate into osteocytes and contribute to endochondral ossification.

Uncertainty-inspired open set learning for retinal anomaly identification

Failure to recognize samples from the classes unseen during training is a major limitation of artificial intelligence in the real-world implementation for recognition and classification of retinal anomalies. We establish an uncertainty-inspired open set (UIOS) model, which is trained with fundus images of 9 retinal conditions. Besides assessing the probability of each category, UIOS also calculates an uncertainty score to express its confidence. Our UIOS model with thresholding strategy achieves an F1 score of 99.55%, 97.01% and 91.91% for the internal testing set, external target categories (TC)-JSIEC dataset and TC-unseen testing set, respectively, compared to the F1 score of 92.20%, 80.69% and 64.74% by the standard AI model. Furthermore, UIOS correctly predicts high uncertainty scores, which would prompt the need for a manual check in the datasets of non-target categories retinal diseases, low-quality fundus images, and non-fundus images. UIOS provides a robust method for real-world screening of retinal anomalies.

6-Gingerol alleviates placental injury in preeclampsia by inhibiting oxidative stress via BNIP3/LC3 signaling-mediated trophoblast mitophagy

Background and aims: Preeclampsia (PE) is the leading cause of maternal and fetal morbidity and mortality worldwide. Apoptosis of trophoblast cells induced by oxidative stress is a principal reason of placental injury in PE. 6-Gingerol, an antioxidant from ginger, plays an important role in many disease models, but its effect on obstetric diseases has not been elucidated. In this study, we investigated the protective effect of 6-gingerol against placental injury. Methods: In vitro hypoxia/reoxygenation (H/R) model of HTR8/Svneo cells and preeclamptic mice model were established to simulate PE. The effects of 6-Gingerol on PE were evaluated by morphological detection, biochemical analysis, and Western blot. Results: We found that H/R treatment induced cell apoptosis, increased the production of reactive oxygen species, malondialdehyde and lactate dehydrogenase, and decreased superoxide dismutase in trophoblast. In addition, the polarization of mitochondrial membrane potential and the cellular calcium flux were also destroyed under H/R condition, which also activated BCL2-interacting protein 3 (BNIP3) and provoked excessive mitophagy. Importantly, 6-Gingerol reversed these corrosive effects. Furthermore, the placenta damage in PE-like mouse caused by the cell apoptosis, oxidative stress and mitophagy was mitigated by 6-Gingerol. Conclusion: These findings suggest that 6-Gingerol exerts a protective effect against placental injury in PE by reducing oxidative stress and inhibiting excessive mitophagy caused by mitochondrial dysfunction.

Myeloid Cells As a Promising Target for Brain-Bone Degenerative Diseases from a Metabolic Point of View

Brain and bone degenerative diseases such as Alzheimer's disease and osteoporosis are common in the aging population and lack efficient pharmacotherapies. Myeloid cells are a diverse group of mononuclear cells that plays important roles in development, immune defense, and tissue homeostasis. Aging drastically alters the expansion and function of myeloid cells, which might be a common pathogenesis of the brain-bone degenerative diseases. From this perspective, the role of myeloid cells in brain-bone degenerative diseases is discussed, with a particular focus on metabolic alterations in myeloid cells. Furthermore, targeting myeloid cells through metabolic regulation via drugs such as metformin and melatonin is proposed as a potential therapy for the clinical treatment of brain-bone diseases.

Cancer cells reprogram to metastatic state through the acquisition of platelet mitochondria

Metastasis is the major cause of cancer deaths, and cancer cells evolve to adapt to various tumor microenvironments, which hinders the treatment of tumor metastasis. Platelets play critical roles in tumor development, especially during metastasis. Here, we elucidate the role of platelet mitochondria in tumor metastasis. Cancer cells are reprogrammed to a metastatic state through the acquisition of platelet mitochondria via the PINK1/Parkin-Mfn2 pathway. Furthermore, platelet mitochondria regulate the GSH/GSSG ratio and reactive oxygen species (ROS) in cancer cells to promote lung metastasis of osteosarcoma. Impairing platelet mitochondrial function has proven to be an efficient approach to impair metastasis, providing a direction for osteosarcoma therapy. Our findings demonstrate mitochondrial transfer between platelets and cancer cells and suggest a role for platelet mitochondria in tumor metastasis.

GMP-grade human neural progenitors delivered subretinally protect vision in rat model of retinal degeneration and survive in minipigs

BACKGROUND

Stem cell products are increasingly entering early stage clinical trials for treating retinal degeneration. The field is learning from experience about comparability of cells proposed for preclinical and clinical use. Without this, preclinical data supporting translation to a clinical study might not adequately reflect the performance of subsequent clinical-grade cells in patients.

METHODS

Research-grade human neural progenitor cells (hNPC) and clinical-grade hNPC (termed CNS10-NPC) were injected into the subretinal space of the Royal College of Surgeons (RCS) rat, a rodent model of retinal degeneration such as retinitis pigmentosa. An investigational new drug (IND)-enabling study with CNS10-NPC was performed in the same rodent model. Finally, surgical methodology for subretinal cell delivery in the clinic was optimized in a large animal model with Yucatan minipigs.

RESULTS

Both research-grade hNPC and clinical-grade hNPC can survive and provide functional and morphological protection in a dose-dependent fashion in RCS rats and the optimal cell dose was defined and used in IND-enabling studies. Grafted CNS10-NPC migrated from the injection site without differentiation into retinal cell phenotypes. Additionally, CNS10-NPC showed long-term survival, safety and efficacy in a good laboratory practice (GLP) toxicity and tumorigenicity study, with no observed cell overgrowth even at the maximum deliverable dose. Finally, using a large animal model with the Yucatan minipig, which has an eye size comparable to the human, we optimized the surgical methodology for subretinal cell delivery in the clinic.

CONCLUSIONS

These extensive studies supported an approved IND and the translation of CNS10-NPC to an ongoing Phase 1/2a clinical trial (NCT04284293) for the treatment of retinitis pigmentosa.

PM2.5 leads to adverse pregnancy outcomes by inducing trophoblast oxidative stress and mitochondrial apoptosis via KLF9/CYP1A1 transcriptional axis

Epidemiological studies have demonstrated that fine particulate matter (PM2.5) is associated with adverse obstetric and postnatal metabolic health outcomes, but the mechanism remains unclear. This study aimed to investigate the toxicological pathways by which PM2.5 damaged placental trophoblasts in vivo and in vitro. We confirmed that PM2.5 induced adverse gestational outcomes such as increased fetal mortality rates, decreased fetal numbers and weight, damaged placental structure, and increased apoptosis of trophoblasts. Additionally, PM2.5 induced dysfunction of the trophoblast cell line HTR8/SVneo, including in its proliferation, apoptosis, invasion, migration and angiogenesis. Moreover, we comprehensively analyzed the transcriptional landscape of HTR8/SVneo cells exposed to PM2.5 through RNA-Seq and observed that PM2.5 triggered overexpression of pathways involved in oxidative stress and mitochondrial apoptosis to damage HTR8/SVneo cell biological functions through CYP1A1. Mechanistically, PM2.5 stimulated KLF9, a transcription factor identified as binding to CYP1A1 promoter region, which further modulated the CYP1A1-driven downstream phenotypes. Together, this study demonstrated that the KLF9/CYP1A1 axis played a crucial role in the toxic progression of PM2.5 induced adverse pregnancy outcomes, suggesting adverse effects of environmental pollution on pregnant females and putative targeted therapeutic strategies.

Multiview Clustering by Consensus Spectral Rotation Fusion

Multiview clustering (MVC) aims to partition data into different groups by taking full advantage of the complementary information from multiple views. Most existing MVC methods fuse information of multiple views at the raw data level. They may suffer from performance degradation due to the redundant information contained in the raw data. Graph learning-based methods often heavily depend on one specific graph construction, which limits their practical applications. Moreover, they often require a computational complexity of O(n3 ) because of matrix inversion or eigenvalue decomposition for each iterative computation. In this paper, we propose a consensus spectral rotation fusion (CSRF) method to learn a fused affinity matrix for MVC at the spectral embedding feature level. Specifically, we first introduce a CSRF model to learn a consensus low-dimensional embedding, which explores the complementary and consistent information across multiple views. We develop an alternating iterative optimization algorithm to solve the CSRF optimization problem, where a computational complexity of O(n2 ) is required during each iterative computation. Then, the sparsity policy is introduced to design two different graph construction schemes, which are effectively integrated with the CSRF model. Finally, a multiview fused affinity matrix is constructed from the consensus low-dimensional embedding in spectral embedding space. We analyze the convergence of the alternating iterative optimization algorithm and provide an extension of CSRF for incomplete MVC. Extensive experiments on multiview datasets demonstrate the effectiveness and efficiency of the proposed CSRF method.

Glucagon-like peptide-1 receptor agonists as a disease-modifying therapy for knee osteoarthritis mediated by weight loss: findings from the Shanghai Osteoarthritis Cohort

OBJECTIVE

Obesity is a risk factor for knee osteoarthritis (KOA) development and progression. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are indicated for type 2 diabetes mellitus (T2DM) and obesity. However, whether KOA patients can benefit from GLP-1RA therapies has not been sufficiently investigated, especially in the long term.

METHODS

The Shanghai Osteoarthritis Cohort study is a prospective, observational, multicentre study of >40 000 adults with clinically diagnosed osteoarthritis aged >45 years in Shanghai. We identified all KOA participants with comorbid T2DM enrolled from 1 January 2011 to 1 January 2017. Primary outcome was incidence of knee surgery after enrolment. Secondary outcomes included pain-relieving medication use, number of intra-articular therapies, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and medial femorotibial joint cartilage thickness. To evaluate the effects of GLP-1RA, we performed before-and-after comparison and comparison with participants who had no GLP-1RA exposure.

RESULTS

For an intergroup comparison (non-GLP-1RA vs GLP-1RA), more weight loss (adjusted mean difference in weight change from baseline -7.29 kg (95% CI -8.07 to -6.50 kg), p<0.001) and lower incidence of knee surgery (93/1574 (5.9%) vs 4/233 (1.7%), adjusted p=0.014) were observed in the GLP-1RA group. Statistically significant differences in mean change from baseline for the WOMAC total and pain subscale scores were observed (adjusted mean difference in WOMAC total score -1.46 (95% CI -2.84 to -0.08), p=0.038; adjusted mean difference in WOMAC pain subscore -3.37 (95% CI -5.79 to -0.94), p=0.007). Cartilage-loss velocity of the medial femorotibial joint was significantly lower in the GLP-1RA group postadjustment for baseline characteristics (adjusted mean difference -0.02 mm (95% CI -0.03 to -0.002 mm), p=0.004). For the before-and-after comparison within the GLP-1RA group, we observed a significant decrease of symptom-relieving medication consumption and cartilage loss velocity of medial femorotibial joint (after-treatment vs before-treatment: -0.03±0.05 vs -0.05±0.07 mm/year, p<0.001). The association between GLP-1RA exposure and decreased incidence of knee surgery was mediated by weight reduction (mediation proportion: 32.1%), instead of glycaemic control (too small to calculate).

CONCLUSION

With sufficient treatment duration, GLP-1RA therapies might be disease-modifying for KOA patients with comorbid T2DM, possibly mediated by weight loss. Further investigation is needed to elucidate effects of GLP-1RA on disease process, joint structure and patient-reported outcomes of osteoarthritis.

Mitochondrial heterogeneity in diseases

As key organelles involved in cellular metabolism, mitochondria frequently undergo adaptive changes in morphology, components and functions in response to various environmental stresses and cellular demands. Previous studies of mitochondria research have gradually evolved, from focusing on morphological change analysis to systematic multiomics, thereby revealing the mitochondrial variation between cells or within the mitochondrial population within a single cell. The phenomenon of mitochondrial variation features is defined as mitochondrial heterogeneity. Moreover, mitochondrial heterogeneity has been reported to influence a variety of physiological processes, including tissue homeostasis, tissue repair, immunoregulation, and tumor progression. Here, we comprehensively review the mitochondrial heterogeneity in different tissues under pathological states, involving variant features of mitochondrial DNA, RNA, protein and lipid components. Then, the mechanisms that contribute to mitochondrial heterogeneity are also summarized, such as the mutation of the mitochondrial genome and the import of mitochondrial proteins that result in the heterogeneity of mitochondrial DNA and protein components. Additionally, multiple perspectives are investigated to better comprehend the mysteries of mitochondrial heterogeneity between cells. Finally, we summarize the prospective mitochondrial heterogeneity-targeting therapies in terms of alleviating mitochondrial oxidative damage, reducing mitochondrial carbon stress and enhancing mitochondrial biogenesis to relieve various pathological conditions. The possibility of recent technological advances in targeted mitochondrial gene editing is also discussed.

Hydrogenated silicene nanosheet functionalized scaffold enables immuno-bone remodeling

An ideal implant needs to have the ability to coordinate the foreign body response and tissue regeneration. Here, Hydrogenated-silicon nanosheets (H-Si NSs) with favorable biodegradability are integrated and functionalized into a β-tricalcium phosphate scaffold (H-Si TCP) for bone defect healing. H-Si TCP can greatly improve bone regeneration through osteoimmunomodulation-guided biodegradation in vivo. The spatiotemporal regulation of degradation products replenishes sufficient nutrients step by step for the entire process of bone repair. Extracellular and intracellular reactive oxygen species (ROS) are first downregulated by reaction with H-Si NSs, followed by marked M2 polarization, remodeling the micro-environment timely for immune-bone regeneration. The release of primary reaction products awakened bone marrow mesenchymal stem cells (BMSCs), which are converted into osteoblasts anchored on scaffolds. Subsequently, biomineralization is promoted by the final degradation products. The intrinsic ROS-responsive, immunoregulatory, and osteo-promotive capability of 2D H-Si NSs makes such composite H-Si TCP scaffold a highly potential alternative for the treatment of critical bone defect.

Distinct differences between calvarial and long bone osteocytes in cell morphologies, gene expression and aging responses

Osteocytes are the terminally differentiated bone cells resulted from bone formation. Although there are two distinct processes of bone formation, intramembranous and endochondral ossifications contributing to the formation of calvarial and long bones, it is not clear whether the distinct pathways determine the differences between calvaria and femoral cortical bone derived osteocytes. In the present study, we employed confocal structured illumination microscopy and mRNA-sequencing analysis to characterize the morphologic and transcriptomic expression of osteocytes from murine calvaria and mid-shaft femoral cortical bone. Structured illumination microscopy and geometric modelling showed round shaped and irregularly scattered calvarial osteocytes compared to spindle shaped and orderly arrayed cortical osteocytes. mRNA-sequencing analysis indicated different transcriptomic profiles between calvarial and cortical osteocytes and provided evidence that mechanical response of osteocytes may contribute to geometrical differences. Furthermore, transcriptomic analysis showed that these two groups of osteocytes come from distinct pathways with 121 ossification-related genes differentially expressed. Analysis of correlation between ossification and osteocyte geometries via a Venn diagram showed that several genes related to ossification, cytoskeleton organization and dendrite development were differentially expressed between calvarial and cortical osteocytes. Finally, we demonstrated that aging disrupted the organization of dendrites and cortical osteocytes but had no significant effects on calvarial osteocytes. Together, we conclude that calvarial and cortical osteocytes are different in various aspects, which is probably the consequence of their distinct pathways of ossification.

[Effect of inactivated SARS-CoV-2 vaccine on the clinical outcomes of patients infected with the Omicron variant in Guangdong Province]

Objective: To evaluate the effect of inactivated SARS-CoV-2 vaccine on the clinical outcomes of patients infected with the Omicron variant. Methods: A total of 1 403 Omicron-infected patients admitted to 20 designated hospitals in Guangdong Province from January 1 to May 31, 2022, were selected as subjects in this study. A case-control study was conducted to collect the demographic data, underlying disease, vaccination status, last exposure date, gene sequencing of infected strains and clinical outcomes from the China Disease Prevention and Control Information System and Guangdong telemedicine platform. Pneumonia (common, severe and critical) and non-pneumonia (asymptomatic and mild) were selected as the case group and control group. The effect of inactivated SARS-CoV-2 vaccine on the clinical outcomes of patients infected with the Omicron variant was analyzed. Results: The median age [M (Q₁, Q₃)] of the subjects was 36 (27-47) years old, with males accounting for 52.25% (733 cases). The main outcome of the infection was non-pneumonia, accounting for 92.09% (1 292 cases), and the duration [M (Q₁, Q₃)] of the disease was 18 (14-22) days. There were 134 (9.55%), 39 (2.78%), 403 (28.72%), 437 (31.15%) and 390 (27.80%) cases with no or partial vaccination, within 90 days of primary vaccination, over 90 days of primary vaccination, within 90 days of booster vaccination and over 90 days of booster vaccination, respectively. Multivariate logistic regression analysis showed that after adjusting for gender, age, underlying disease, and location of the report, compared with those with no or partial vaccination, the risk of developing pneumonia was lower in those with over 90 days of primary vaccination, within 90 days of booster vaccination and over 90 days of booster vaccination [OR (95%CI) values were 0.52 (0.28-0.98), 0.39 (0.21-0.73) and 0.40 (0.21-0.77), respectively]. Cox proportional hazard regression model analysis showed that after adjusting for gender, age, underlying disease and location of the report, the duration of the disease was shorter in those who received booster vaccinated for more than 90 days compared with that in those who had no or partial vaccination [HR (95%CI): 1.26 (1.03-1.55)]. Conclusion: The inactivated SARS-CoV-2 vaccine affects the clinical outcomes of patients infected with the Omicron variant.

A prophylactic lumbosacral brace and the biomechanics of parachute landing

Background

Lumbar injuries are common among paratroopers during landing maneuvers. Although bracing is widely advocated to increase spine stability, the effect of lumbar bracing on parachuting has yet to be quantified and the Chinese parachutist does not have a uniform prophylactic brace. The aim is to compare the effects of a novel, self-designed and self-manufactured lumbosacral brace with two ordinary lumbar braces based on biomechanical assessment of the lumbar and lower extremity joints during parachute landing.

Methods

The study cohort consisted of 30 elite male paratroopers. Each participant was instructed to jump off a platform at two different heights (60 and 120 cm, respectively) and land on the force plate in a half-squat posture. Participants at each height were tested under four different conditions (no brace, elastic brace, semi-rigid brace, and lumbosacral brace). The Vicon 3D motion capture system and force plate were used to record and calculate biomechanical data, such as vertical ground reaction forces (vGRFs), joint angles, moments, and energy absorption. After the experiment, every participant completed the study questionnaires.

Results

The increase of the jumping height raised all the parameters significantly (P<0.01). The use of all three braces slightly decreased vGRF, and reduced the lumbar angle, moment, and angular velocity in the sagittal plane. The use of lumbosacral and semi-rigid braces restricted lumbar flexion more efficiently (P<0.05), and significantly increased the energy absorption of the hip joints (P<0.01) and hip flexion (P<0.01) at 120 cm. No significant effect of braces was found on the motion of knee and ankle joints. The subjective scores suggested that the lumbosacral brace was softer and more comfortable than the semi-rigid brace, and more effective than the elastic brace.

Conclusions

The lumbosacral brace markedly restricted the lumbar motion in the sagittal plane than the elastic brace and was more comfortable than the semi-rigid brace. Therefore, the innovative design, high efficiency, and comfortable landing of the lumbosacral brace represent a reliable option for parachute jumping and training.

Sexual activity satisfaction in symptomatic hip osteoarthritis patients: A cross-sectional, national web-based study

AIM

Despite high-interest rates in sex in people with hip osteoarthritis (OA), clinicians tend not to address sexual issues, especially in older adults. The objective of this study is to evaluate sexual activity and factors associated with sexual activity satisfaction in people with symptomatic hip OA.

METHODS

A cross-sectional study was conducted among 252 participants with symptomatic hip OA in Australia. Quality of sex life was assessed using the online composite of sexual activities and positions questionnaires. A Poisson model with robust variance was used to calculate the prevalence ratio (PR). Factors that showed a univariate association with sexual satisfaction were then included in a multivariable model. PR with corresponding 95% confidence intervals (CI) are reported.

RESULTS

Among the 282 participants registered on the study website, 252 met the inclusion criteria, and 60.3% (152/252) completed the sexual activity questionnaires. Hip OA interfered with sexual activity in 70.0% of the participants. High confidence in completing sexual activity (PR: 0.53, 95% CI: 0.36 to 0.77) was associated with an increased prevalence ratio of sexual satisfaction. High anxiety, depression or stress during sexual activity (PR: 1.33, 95% CI: 1.10 to 1.60) was associated with an increased prevalence ratio of sexual dissatisfaction after adjusting for hip pain level and perceived partner's orgasm.

CONCLUSION

Although a large proportion of people with hip OA remain sexually active, a substantial proportion of persons are dissatisfied with their sexual activity. Hip OA interfered with sexual activity in most participants. Psychological factors were found to be associated with sexual activity satisfaction.

A median fin derived from the lateral plate mesoderm and the origin of paired fins

The development of paired appendages was a key innovation during evolution and facilitated the aquatic to terrestrial transition of vertebrates. Largely derived from the lateral plate mesoderm (LPM), one hypothesis for the evolution of paired fins invokes derivation from unpaired median fins via a pair of lateral fin folds located between pectoral and pelvic fin territories1. Whilst unpaired and paired fins exhibit similar structural and molecular characteristics, no definitive evidence exists for paired lateral fin folds in larvae or adults of any extant or extinct species. As unpaired fin core components are regarded as exclusively derived from paraxial mesoderm, any transition presumes both co-option of a fin developmental programme to the LPM and bilateral duplication2. Here, we identify that the larval zebrafish unpaired pre-anal fin fold (PAFF) is derived from the LPM and thus may represent a developmental intermediate between median and paired fins. We trace the contribution of LPM to the PAFF in both cyclostomes and gnathostomes, supporting the notion that this is an ancient trait of vertebrates. Finally, we observe that the PAFF can be bifurcated by increasing bone morphogenetic protein signalling, generating LPM-derived paired fin folds. Our work provides evidence that lateral fin folds may have existed as embryonic anlage for elaboration to paired fins.

The RhWRKY33a-RhPLATZ9 regulatory module delays petal senescence by suppressing rapid reactive oxygen species accumulation in rose flowers

Redox homeostasis in plant cells is critical for maintaining normal growth and development because reactive oxygen species (ROS) can function as signaling molecules or toxic compounds. However, how plants fine-tune redox homeostasis during natural or stress-induced senescence remains unclear. Cut roses (Rosa hybrida), an economically important ornamental product worldwide, often undergo stress-induced precocious senescence at the post-harvest bud stage. Here, we identified RhPLATZ9, an age- and dehydration-induced PLATZ (plant AT-rich sequence and zinc-binding) protein, and determined that it functions as a transcriptional repressor in rose flowers during senescence. We also showed that RhWRKY33a regulates RhPLATZ9 expression during flower senescence. RhPLATZ9-silenced flowers and RhWRKY33a-silenced flowers showed accelerated senescence, with higher ROS contents than the control. By contrast, overexpression of RhWRKY33a or RhPLATZ9 delayed flower senescence, and overexpression in rose calli showed lower ROS accumulation than the control. RNA-sequencing analysis revealed that apoplastic NADPH oxidase genes (RhRbohs) were enriched among the upregulated differentially expressed genes in RhPLATZ9-silenced flowers compared to wild-type flowers. Yeast one-hybrid assays, electrophoretic mobility shift assays, dual luciferase assays and chromatin immunoprecipitation quantitative PCR confirmed that the RhRbohD gene is a direct target of RhPLATZ9. These findings suggest that the RhWRKY33a-RhPLATZ9-RhRbohD regulatory module acts as a brake to help maintain ROS homeostasis in petals and thus antagonize age- and stress-induced precocious senescence in rose flowers.

In-hospital waiting time to surgery and functional outcomes in geriatric hip fractures: a directed acyclic graph-based preplanned analysis from a prospective multicenter cohort study

BACKGROUND

The early recovery of hip function after hip fracture surgery values more attention, especially for patients with delayed surgery of longer than 48 h. We aim to evaluate the associations of in-hospital surgical waiting time with the functional outcomes [Harris Hip Score (HHS), Parker Mobility Score (PMS), and EuroQol 5 dimensions VAS (visual analogue scale) score (EQ-5D VAS)] in elderly patients who sustained hip fractures.

MATERIALS AND METHODS

Data on sociodemographic and clinical factors were prospectively collected using a multicenter hip fracture registry system. Participants in the cohort underwent a 12-month follow-up investigation. After adjusting potential confounders identified by the directed acyclic graphs, the associations between surgical waiting time longer than 48 h and functional outcomes were estimated by log-binomial regression and multivariable linear regression models with generalized estimating equations.

RESULTS

Of 863 survival participants with available functional data at 12 months after surgery, an increased risk was obtained from receiving surgery after 48 h and the poor functional outcomes (HHS<80: relative risk (RR)=1.56, 95% CI: 1.00-2.51; PMS<7: RR=1.49, 95% CI: 1.13-2.01; EQ-5D VAS<80: RR=1.97, 95% CI: 1.57-2.47). In-hospital waiting time greater than 48 h were time-invariantly associated with lower PMS during recovery (-0.44 units 95% CI: -0.70 to -0.18). In addition, delayed surgery was time-varying associated with HHS and EQ-5D VAS.

CONCLUSIONS

The associations between in-hospital waiting time and postoperative functional score suggest that delayed surgery can lead to poor functional outcomes, especially in patients waiting longer than 72 h from injury. Delayed surgery mainly impacted hip function and mobility recovery with a slower speed in early recovery of the first 3 months. More attention should be paid to mechanisms behind the associations between delayed surgery on general healthy status.

[Analysis of incidence and clinical characteristics of osteonecrosis of femoral head in patients with systemic lupus erythematosus treated with glucocorticoid: A descriptive study based on a prospective cohort]

Objective

To describe the disease characteristics of osteonecrosis of the femoral head (ONFH) in patients with systemic lupus erythematosus (SLE) who experiencing prolonged glucocorticoid (GC) exposure.

Methods

Between January 2016 and June 2019, 449 SLE patients meeting the criteria were recruited from multiple centers. Hip MRI examinations were performed during screening and regular follow-up to determine the occurrence of ONFH. The cohort was divided into ONFH and non-ONFH groups, and the differences in demographic baseline characteristics, general clinical characteristics, GC medication information, combined medication, and hip clinical features were compared and comprehensively described.

Results

The age at SLE diagnosis was 29.8 (23.2, 40.9) years, with 93.1% (418 cases) being female. The duration of GC exposure was 5.3 (2.0, 10.5) years, and the cumulative incidence of SLE-ONFH was 9.1%. Significant differences ( P<0.05) between ONFH and non-ONFH groups were observed in the following clinical characteristics: ① Demographic baseline characteristics: ONFH group had a higher proportion of patients with body mass index (BMI)<20 kg/m ² compared to non-ONFH group. ② General clinical characteristics: ONFH group showed a higher proportion of patients with cutaneous and renal manifestations, positive antiphospholipid antibodies (aPLs) and anticardiolipin antibodies, severe SLE patients [baseline SLE Disease Activity Index 2000 (SLEDAI-2K) score ≥15], and secondary hypertension. Fasting blood glucose in ONFH group was also higher. ③ GC medication information: ONFH group had higher initial intravenous GC exposure rates, duration, cumulative doses, higher cumulative GC doses in the first month and the first 3 months, higher average daily doses in the first 3 months, and higher proportions of average daily doses ≥15.0 mg/d and ≥30.0 mg/d, as well as higher full-course average daily doses and proportion of full-course daily doses ≥30.0 mg/d compared to non-ONFH group. ④ Combined medications: ONFH group had a significantly higher rate of antiplatelet drug use than non-ONFH group. ⑤ Hip clinical features: ONFH group had a higher proportion of hip discomfort or pain and a higher incidence of hip joint effusion before MRI screening than non-ONFH group.

Conclusion

The incidence of ONFH after GC exposure in China's SLE population remains high (9.1%), with short-term (first 3 months), medium-to-high dose (average daily dose ≥15 mg/d) GC being closely associated with ONFH. Severe SLE, low BMI, certain clinical phenotypes, positive aPLs, and secondary hypertension may also be related to ONFH.

Apposition of fibroblasts with metaplastic gastric cells promotes dysplastic transition

BACKGROUND & AIMS

Elements of field cancerization including atrophic gastritis, metaplasia and dysplasia promote gastric cancer development in association with chronic inflammation. However, it remains unclear how stroma changes during carcinogenesis and how the stroma contributes to progression of gastric preneoplasia. Here we investigated heterogeneity of fibroblasts, one of the most important elements in the stroma, and their roles in neoplastic transformation of metaplasia.

METHODS

We utilized single cell transcriptomics to evaluate the cellular heterogeneity of mucosal cells from human gastric cancer patients. Tissue sections from the same cohort and tissue microarrays were used to identify the geographical distribution of distinct fibroblast subsets. We further evaluated the role of fibroblasts from pathologic mucosa in dysplastic progression of metaplastic cells using patient-derived metaplastic gastroids and fibroblasts.

RESULTS

We identified four subsets of fibroblasts within stromal cells defined by the differential expression of PDGFRA, FBLN2, ACTA2 or PDGFRB. Each subset was distributed distinctively throughout stomach tissues with different proportions at each pathologic stage. The PDGFRα⁺ subset expanded in metaplasia and cancer compared with normal, maintaining a close proximity with the epithelial compartment. Co-culture of metaplasia- or cancer-derived fibroblasts with gastroids showing the characteristics of spasmolytic polypeptide-expressing metaplasia (SPEM) induced disordered growth, loss of metaplastic markers and increases in markers of dysplasia. Culture of metaplastic gastroids with conditioned media from metaplasia- or cancer-derived fibroblasts also promoted dysplastic transition.

CONCLUSIONS

These findings indicate that fibroblast associations with metaplastic epithelial cells can facilitate direct transition of metaplastic SPEM cell lineages into dysplastic lineages.

Generation of Albino Phenotype in Ornamental Fish by CRISPR/Cas9-Mediated Genome Editing of slc45a2 Gene

Albinism is the most common color variation described in fish and is a fascinating trait of some ornamental fish species. Albino mutants can be generated by knocking out core genes affecting melanin synthesis like slc45a2 in several fish species. However, genetic mutation remains challenging for species with unknown genome information. In this study, we generated albino mutants in two selected ornamental fish species, royal farlowella (Sturisoma panamense), and redhead cichlid (Vieja melanura). For this purpose, we carried out phylogenetic analyses of fish slc45a2 sequences and identified a highly conserved region among different fish species. A pair of degenerate primers spanning this region was designed and used to amplify a conserved slc45a2 fragment of 340 bp from the two fish species. Based on the amplified sequences, a target site in the 6^th exon was used for designing guide RNA and this targeted site was first verified by the CRISPR/Cas9 system in the zebrafish (Danio rerio) model for the effectiveness. Then, specific guide RNAs were designed for the two ornamental fish species and tested. Most of the injected larvae completely lost black pigment over the whole body and eyes. DNA sequencing confirmed a high degree of mutation at the targeted site. Overall, we described a fast and efficient method to generate albino phenotype in fish species by targeting the conserved 6^th exon of slc45a2 gene for genome editing via CRISPR/Cas9 and this approach could be a new genetic tool to generate desirable albino ornamental fish.

Knockdown of PLAGL2 in hibits oral squamous cell carcinoma cell growth and cisplatin resistance via ZEB1/PD L1 pathway

Purpose: To investigate the effects of pleomorphic adenoma gene like-2 (PLAGL2) on oral squamous cell carcinoma (OSCC). Methods: The effects of PLAGL2 on OSCC (CAL-27 and HSC-3) were conducted with loss- and gain-functional assays. Cell proliferation was determined by Cell Counting Kit-8 (CCK8) and colony formation assays. Cell metastasis was assessed by Transwell and wound healing assays. Cell apoptosis of cisplatin-resistant OSCC was evaluated by flow cytometry. Results: PLAGL2 expression was significantly elevated in OSCC (p < 0.001), while silencing of PLAGL2 significantly reduced cell proliferation and metastasis of OSCC (p < 0.001). However, overexpression of PLAGL2 promoted OSCC progression through increase in cell proliferation, invasion, and migration. Knockdown of PLAGL2 promoted cell apoptosis of -resistant OSCC, but significantly downregulated protein expression of programmed cell death ligand 1(PD-L1) and zinc finger E-box-binding homeobox 1 (ZEB1) in OSCC (p < 0.01). Moreover, loss of ZEB1 attenuated the PLAGL2 overexpression-induced increase in ZEB1 and PD-L1. Loss of PLAGL2 also reduced in vivo tumor growth of OSCC via regulation of cluster of differentiation 4 protein (CD4) and CD8. Conclusion: Knockdown of PLAGL2 exerts anti-tumor effects, improves cisplatin resistance, and enhances anti-tumor immunity in OSCC through suppression of ZEB1/PD-L1 pathway. Thus, PLAGL2 might be a potential therapeutic target for the treatment of OSCC.

Trusted Multi-View Classification With Dynamic Evidential Fusion

Existing multi-view classification algorithms focus on promoting accuracy by exploiting different views, typically integrating them into common representations for follow-up tasks. Although effective, it is also crucial to ensure the reliability of both the multi-view integration and the final decision, especially for noisy, corrupted and out-of-distribution data. Dynamically assessing the trustworthiness of each view for different samples could provide reliable integration. This can be achieved through uncertainty estimation. With this in mind, we propose a novel multi-view classification algorithm, termed trusted multi-view classification (TMC), providing a new paradigm for multi-view learning by dynamically integrating different views at an evidence level. The proposed TMC can promote classification reliability by considering evidence from each view. Specifically, we introduce the variational Dirichlet to characterize the distribution of the class probabilities, parameterized with evidence from different views and integrated with the Dempster-Shafer theory. The unified learning framework induces accurate uncertainty and accordingly endows the model with both reliability and robustness against possible noise or corruption. Both theoretical and experimental results validate the effectiveness of the proposed model in accuracy, robustness and trustworthiness.

Structural Attention Graph Neural Network for Diagnosis and Prediction of COVID-19 Severity

With rapid worldwide spread of Coronavirus Disease 2019 (COVID-19), jointly identifying severe COVID-19 cases from mild ones and predicting the conversion time (from mild to severe) is essential to optimize the workflow and reduce the clinician's workload. In this study, we propose a novel framework for COVID-19 diagnosis, termed as Structural Attention Graph Neural Network (SAGNN), which can combine the multi-source information including features extracted from chest CT, latent lung structural distribution, and non-imaging patient information to conduct diagnosis of COVID-19 severity and predict the conversion time from mild to severe. Specifically, we first construct a graph to incorporate structural information of the lung and adopt graph attention network to iteratively update representations of lung segments. To distinguish different infection degrees of left and right lungs, we further introduce a structural attention mechanism. Finally, we introduce demographic information and develop a multi-task learning framework to jointly perform both tasks of classification and regression. Experiments are conducted on a real dataset with 1687 chest CT scans, which includes 1328 mild cases and 359 severe cases. Experimental results show that our method achieves the best classification (e.g., 86.86% in terms of Area Under Curve) and regression (e.g., 0.58 in terms of Correlation Coefficient) performance, compared with other comparison methods.

Less sclerotic microarchitecture pattern with increased bone resorption in glucocorticoid-associated osteonecrosis of femoral head as compared to alcohol-associated osteonecrosis of femoral head

BACKGROUND

Glucocorticoid usage and alcohol abuse are the most widely accepted risk factors for nontraumatic osteonecrosis of femoral head (ONFH). Despite distinct etiologies between glucocorticoid-associated ONFH (GONFH) and alcohol-associated ONFH (AONFH), little is known about the differences of the microarchitectural and histomorphologic characteristics between these subtypes of ONFH.

PURPOSES

To investigate bone microarchitecture, bone remodeling activity and histomorphology characteristics of different regions in femoral heads between GONFH and AONFH.

METHODS

From September 2015 to October 2020, 85 patients diagnosed with GONFH and AONFH were recruited. Femoral heads were obtained after total hip replacement. Femoral head specimens were obtained from 42 patients (50 hips) with GONFH and 43 patients (50 hips) with AONFH. Micro-CT was utilized to assess the microstructure of 9 regions of interest (ROIs) in the femoral head. Along the supero-inferior orientation, the femoral head was divided into necrotic region, reactive interface, and normal region; along the medio-lateral orientation, the femoral head was divided into medial region, central region and lateral region. Decalcified and undecalcified bone histology was subsequently performed to evaluate histopathological alterations and bone remodeling levels.

RESULTS

In the necrotic region, most of the microarchitectural parameters did not differ significantly between GONFH and AONFH, whereas both the reactive interface and normal region revealed a less sclerotic microarchitecture but a higher bone remodeling level in GONFH than AONFH. Despite similar necrotic pathological manifestations, subchondral trabecular microfracture in the necrotic region was more severe and vasculature of the reactive interface was more abundant in GONFH.

CONCLUSIONS

GONFH and AONFH shared similar microarchitecture and histopathological features in the necrotic region, while GONFH exhibited a less sclerotic microarchitecture and a more active bone metabolic status in both the reactive interface and normal region. These differences between GONFH and AONFH in bone microarchitectural and histopathological characteristics might contribute to the development of disease-modifying prevention strategies and treatments for ONFH, taking into etiologies.

SGU-Net: Shape-Guided Ultralight Network for Abdominal Image Segmentation

Convolutional neural networks (CNNs) have achieved significant success in medical image segmentation. However, they also suffer from the requirement of a large number of parameters, leading to a difficulty of deploying CNNs to low-source hardwares, e.g., embedded systems and mobile devices. Although some compacted or small memory-hungry models have been reported, most of them may cause degradation in segmentation accuracy. To address this issue, we propose a shape-guided ultralight network (SGU-Net) with extremely low computational costs. The proposed SGU-Net includes two main contributions: it first presents an ultralight convolution that is able to implement double separable convolutions simultaneously, i.e., asymmetric convolution and depthwise separable convolution. The proposed ultralight convolution not only effectively reduces the number of parameters but also enhances the robustness of SGU-Net. Secondly, our SGUNet employs an additional adversarial shape-constraint to let the network learn shape representation of targets, which can significantly improve the segmentation accuracy for abdomen medical images using self-supervision. The SGU-Net is extensively tested on four public benchmark datasets, LiTS, CHAOS, NIH-TCIA and 3Dircbdb. Experimental results show that SGU-Net achieves higher segmentation accuracy using lower memory costs, and outperforms state-of-the-art networks. Moreover, we apply our ultralight convolution into a 3D volume segmentation network, which obtains a comparable performance with fewer parameters and memory usage. The available code of SGUNet is released at https://github.com/SUST-reynole/SGUNet.

Loss of linker histone H1 in the maternal genome influences DEMETER-mediated demethylation and affects the endosperm DNA methylation landscape

The Arabidopsis DEMETER (DME) DNA glycosylase demethylates the central cell genome prior to fertilization. This epigenetic reconfiguration of the female gamete companion cell establishes gene imprinting in the endosperm and is essential for seed viability. DME demethylates small and genic-flanking transposons as well as intergenic and heterochromatin sequences, but how DME is recruited to these loci remains unknown. H1.2 was identified as a DME-interacting protein in a yeast two-hybrid screen, and maternal genome H1 loss affects DNA methylation and expression of selected imprinted genes in the endosperm. Yet, the extent to which H1 influences DME demethylation and gene imprinting in the Arabidopsis endosperm has not been investigated. Here, we showed that without the maternal linker histones, DME-mediated demethylation is facilitated, particularly in the heterochromatin regions, indicating that H1-bound heterochromatins are barriers for DME demethylation. Loss of H1 in the maternal genome has a very limited effect on gene transcription or gene imprinting regulation in the endosperm; however, it variably influences euchromatin TE methylation and causes a slight hypermethylation and a reduced expression in selected imprinted genes. We conclude that loss of maternal H1 indirectly influences DME-mediated demethylation and endosperm DNA methylation landscape but does not appear to affect endosperm gene transcription and overall imprinting regulation.

[Potential application of improved hard tissue section technique in the clinical pathological diagnosis of bone and bone marrow]

Objective: To discuss the application value of hard tissue section in the clinicopathology diagnosis. Methods: From March 2021 to December 2021, bone slices of 19 patients (1 patient with osteochondroma, 2 patients with chondrosarcoma, 4 patients with osteosarcoma, 2 patients with fibrous dysplasia, 2 patients with bone metastasis from thyroid papillary carcinoma, 2 patients with osteomyelitis, 4 patients with giant cell tumor of bone, 2 patients with Ewing sarcoma) and 16 hemopathy patients were collected from the Department of Pathology, Shanghai Sixth People's Hospital. Of the osteopathy patients, there were 14 male and 5 female with a median age of 31 (10-66) years. Meanwhile, there were 7 male and 9 female with a median age of 28 (16-65) years among these hemopathy patients. Thirty-five cases were treated with modified hard tissue slicing technique and paraffin embedding technique, respectively. The advantages and disadvantages of the two methods for clinical diagnosis of bone disease were compared by Hematoxylin-Eosin staining (H&E staining), immunohistochemical staining (IHC), fluorescence in situ hybridization (FISH) and Sanger sequencing. Results: The improved resin-embedded method showed better histological morphology and cell structure. Besides, the expression of Ki67, SATB2, CD34, SMA, CD68,MPO,CD4 and CD33 in immunohistochemical staining in bone tissues which were embedded in resin were more clear in the accurate positive localization than those using paraffin-embedded. MDM2 of FISH exhibited a higher fluorescence intensity and more accurate location. Meanwhile, both methods treated with Sanger sequencing met the requirements of DNA purity and mutation detection. Conclusion: The improved hard tissue section method is simple and short time-consuming, which is suitable for optimizing the clinical bone and bone marrow pathological diagnosis process.

Characterization of zearalenone-induced hepatotoxicity and its mechanisms by transcriptomics in zebrafish model

Zearalenone is a mycotoxin produced by several species of Fusarium fungi, which contaminates crop and cereal products worldwide. It is widely distributed and can be transported from agricultural fields to the aquatic environment via soil run-off. Zearalenone exposure can cause serious health problems to humans and animals, including estrogenic, immunotoxic, and xenogenic effects. Though its hepatotoxicity has been reported by few studies, the underlying mechanisms are yet to be investigated. This study aimed to comprehensively evaluate the hepatotoxic effects of zearalenone and its molecular mechanism in the zebrafish model system. First, we found zearalenone exposure can cause liver injury, as evidenced by reduced liver size, decreased liver-specific fluorescence, increased aspartate aminotransferase (AST) activity, delayed yolk sac absorption and lipid accumulation. Then, RNA sequencing (RNA-seq) was performed using dissected zebrafish fry liver, which found genes involved in oxidation and reduction were significantly enriched. Quantitative real-time PCR further confirmed the dysregulated expression of several antioxidant enzymes. Additionally, lipid peroxidation was proved by increased malondialdehyde (MDA) production and gene expression at the mRNA level. In contrast to the previous study, apoptosis was likely decreased in response to zearalenone exposure. Last, glucuronidation and amino acid metabolism were also disrupted by zearalenone. Our results revealed the complex mechanism of zearalenone-induced hepatotoxicity, which is a valuable contribution to a more comprehensive understanding of the toxicity of zearalenone.

The impact of facemask on patients with COPD: A systematic review and meta-analysis

Background

Since the emergence of COVID-19, mandatory facemask wearing has been implemented around the world to prevent viral transmission, however, the impact of wearing facemasks on patients with COPD was unclear.

Methods

The current study undertakes a systematic review and meta-analysis of a comprehensive literature retrieval from six databases, based on the pre-determined eligibility criteria, irrespective of language. The risk of bias was assessed using an established instrument. We primarily focused on analyzing ETCO₂, SpO₂, and heart and respiratory rates, and also considered the impacts on physiological and exercise performance. A descriptive summary of the data and possible meta-analysis was performed. Forest plots were generated to pool estimates based on each of the study outcomes.

Results

Of the 3,751 publications considered, six publications were selected for a systematic review and two publications were included for meta-analysis, however, the quality of these six studies was relatively low overall. In the case of inactivity, the facemask wearing COPD cohort had higher respiratory rates than that of the non-facemask wearing cohort (MD = 1.00 and 95% CI 0.47-1.53, P < 0.05). There was no significant difference in ETCO₂ (MD = 0.10 and 95% CI -1.57-1.78, P > 0.05) and heart rate (MD = 0.40 and 95% CI -3.59-4.39, P > 0.05) nor SpO₂ (MD = -0.40 and 95% CI -0.84-0.04, P > 0.05) between the COPD patients with and without facemasks. Furthermore, it was observed that the only significant differences between the COPD patients with and without facemasks undertaking different activities were FEV1 (%) (MD = 3.84 and 95% CI 0.14-7.54, P < 0.05), FEV1/FVC (%) (MD = 3.25 and 95% CI 0.71-5.79, P < 0.05), and blood lactate (MD = -0.90 and 95% CI -1.73 to -0.07, P < 0.05).

Conclusion

Wearing facemasks decreased the exercise performance of patients with COPD, however, it had minimal impact on physiological indexes. Further investigations will be performed on the high-quality data from randomized control studies.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=326265, identifier: CRD42022326265.