Vorinostat ameliorates IL-1α-induced reduction of type II collagen by inhibiting the expression of ELF3 in chondrocytes.

Osteoarthritis (OA) is a common joint disease that ultimately causes physical disability and imposes an economic burden on society. Cartilage destruction plays a key role in the development of OA. Vorinostat is an oral histone deacetylase (HDAC) inhibitor and has been used for the treatment of T-cell lymphoma. Previous studies have reported the anti-inflammatory effect of HDAC inhibitors in both in vivo and in vitro models. However, it is unknown whether vorinostat exerts a protective effect in OA. In this study, our results demonstrate that treatment with vorinostat prevents interleukin 1α (IL-1α)-induced reduction of type II collagen at both gene and protein levels. Treatment with vorinostat reduced the IL-1α-induced production of mitochondrial reactive oxygen species (ROS) in T/C-28a2 cells. Additionally, vorinostat rescued the IL-1α-induced decrease in the expression of the collagen type II a1 (Col2a1) gene and the expression of Sry-related HMG box 9 (SOX-9). Importantly, we found that vorinostat inhibited the expression of matrix metalloproteinase-13 (MMP-13), which is responsible for the degradation of type II collagen. Furthermore, vorinostat suppressed the expression of E74-like factor 3 (ELF3), which is a key transcription factor that plays a pivotal role in the IL-1α-induced reduction of type II collagen. Also, the overexpression of ELF3 abolished the protective effects of vorinostat against IL-1α-induced loss of type 2 collagen by inhibiting the expression of SOX-9 whilst increasing the expression of MMP-13. In conclusion, our findings suggest that vorinostat might prevent cartilage destruction by rescuing the reduction of type II collagen, mediated by the suppression of ELF3.

Antiangiogenic effect of arsenic trioxide in HUVECs by FoxO3a-regulated autophagy.

Arsenic trioxide (ATO) has been shown to have antitumor effect in different tumors, although the underlying mechanisms are not fully understood. Autophagy plays a critical role in tumorigenesis and cancer therapy and has been found to be activated by ATO in different cells. However, the role of autophagy in the antitumor effect of ATO has not yet been elucidated. In this study, we investigated the role of autophagy in the antiangiogenic effect of ATO in human umbilical vein endothelial cells (HUVECs) in vitro and its underlying mechanism. Our data showed that ATO suppresses angiogenesis and induces autophagy in HUVECs through upregulation of forkhead box protein O3 (FoxO3a). Co-incubated with autophagy inhibitor or knockdown of FoxO3a effectively inhibited ATO-induced autophagy and reversed the antiangiogenic effect of ATO, indicating that ATO-induced autophagy plays an antiangiogenic role in HUVECs. Our results highlight the importance of autophagy in the antiangiogenic effect of ATO and provide an improved understanding of the function of ATO.

Arsenic Trioxide Suppressed Migration and Angiogenesis by Targeting FOXO3a in Gastric Cancer Cells.

Arsenic trioxide (As2O3), a traditional remedy in Chinese medicine, has been used in acute promyelocytic leukemia (APL) research and clinical treatment. Previous studies have shown that As2O3 exerts its potent antitumor effects in solid tumors by regulating cell proliferation and survival. The aim of this study was to investigate whether As2O3 inhibited gastric cancer cell migration and angiogenesis by regulating FOXO3a expression. We found that As2O3 reduced gastric cancer cell viability in a dose-dependent manner and also inhibited cell migration and angiogenesis in vitro. Western blotting and immunofluorescence showed that As2O3 downregulated the levels of p-AKT, upregulated FOXO3a expression in the nucleus, and attenuated downstream Vascular endothelial growth factor (VEGF) and Matrix metallopeptidase 9 (MMP9) expression. Moreover, we demonstrated that knockdown of FOXO3a significantly reversed the inhibition of As2O3 and promoted cell migration and angiogenesis in vitro. Further, As2O3 significantly inhibited xenograft tumor growth and angiogenesis by upregulating FOXO3a expression in vivo. However, knockdown of FOXO3a attenuated the inhibitory effect of As2O3 in xenograft tumors, and increased microvessel density (MVD) and VEGF expression. Our results demonstrated that As2O3 inhibited migration and angiogenesis of gastric cancer cells by enhancing FOXO3a expression.

Cryo-FIB specimen preparation for use in a cartridge-type cryo-TEM.

Cryo-electron tomography (cryo-ET) is a well-established technique for studying 3D structural details of subcellular macromolecular complexes and organelles in their nearly native context in the cell. A primary limitation of the application of cryo-ET is the accessible specimen thickness, which is less than the diameters of almost all eukaryotic cells. It has been shown that focused ion beam (FIB) milling can be used to prepare thin, distortion-free lamellae of frozen biological material for high-resolution cryo-ET. Commercial cryosystems are available for cryo-FIB specimen preparation, however re-engineering and additional fixtures are often essential for reliable results with a particular cryo-FIB and cryo-transmission electron microscope (cryo-TEM). Here, we describe our optimized protocol and modified instrumentation for cryo-FIB milling to produce thin lamellae and subsequent damage-free cryotransfer of the lamellae into our cartridge-type cryo-TEM.

Treatment of Calcified Insertional Achilles Tendinopathy by the Posterior Midline Approach.

The present study investigated the clinical outcomes of the posterior midline approach in the treatment of 34 patients with significantly calcified insertional Achilles tendinopathy. The posterior midline approach was applied for the surgical treatment of 34 patients with chronic significantly calcified insertional Achilles tendinopathy after failed conservative treatment. Gastrocnemius recession was performed simultaneously for patients with gastrocnemius contracture. The Fowler-Philip angle and parallel pitch lines were measured before surgery, and the visual analog scale, Tegner score, and Victorian Institute of Sport tendon study group score were recorded before and after surgery. The mean follow-up period was 45.2 ± 17.7 (range 24 to 84) months. After surgery, the visual analog scale score had decreased notably, and the Tegner score and Victorian Institute of Sport tendon study group score had increased significantly. The posterior midline approach can achieve satisfactory outcomes in the treatment of significantly calcified insertional Achilles tendinopathy, and gastrocnemius recession (Strayer procedure) should be performed for patients with gastrocnemius contracture to improve the surgical outcome.

A new selaginellin derivative from Selaginella pulvinata.

Abstract: A new selaginellin derivative named as selaginellin S (1) was isolated from the whole plants of Selaginella pulvinata (Hook. et Grev.) Maxim. (Selaginellaceae), together with a known one (selaginellin M, 2). Compounds 1 and 2 were separated and purified by silica gel and Sephadex LH-20 column chromatography. Their structures were determined on the basis of extensive spectroscopic analysis including IR, MS, 1D and 2D NMR experiments, as well as ECD calculations. Compound 1 is a key intermidiant in the biosynthesis pathway of selaginellins. Compound 2 is first reported in this plant.

Cellular chaperonin CCTγ contributes to rabies virus replication during infection.

Rabies, as the oldest known infectious disease, remains a serious threat to public health worldwide. The eukaryotic cytosolic chaperonin TRiC/CCT complex facilitates the folding of proteins through ATP hydrolysis. Here, we investigated the expression, cellular localization, and function of neuronal CCTγ during neurotropic rabies virus (RABV) infection using mouse N2a cells as a model. Following RABV infection, 24 altered proteins were identified by using two-dimensional electrophoresis and mass spectrometry, including 20 upregulated proteins and 4 downregulated proteins. In mouse N2a cells infected with RABV or cotransfected with RABV genes encoding nucleoprotein (N) and phosphoprotein (P), confocal microscopy demonstrated that upregulated cellular CCTγ was colocalized with viral proteins N and P, which formed a hollow cricoid inclusion within the region around the nucleus. These inclusions, which correspond to Negri bodies (NBs), did not form in mouse N2a cells only expressing the viral protein N or P. Knockdown of CCTγ by lentivirus-mediated RNA interference led to significant inhibition of RABV replication. These results demonstrate that the complex consisting of viral proteins N and P recruits CCTγ to NBs and identify the chaperonin CCTγ as a host factor that facilitates intracellular RABV replication. This work illustrates how viruses can utilize cellular chaperonins and compartmentalization for their own benefit.

Comparative proteomics analysis of host cells infected with Brucella abortus A19.

We carried out a proteomic analysis of THP-1-derived macrophages with and without Brucella abortus A19 (B. abortus A19) infection in order to study the cellular responses to B. abortus A19. The proteins were analyzed at different time points after infection with 2DE followed by MALDI-TOF/TOF identification. Comparative analysis of multiple 2DE gels revealed that the majority of changes in protein abundance appeared between 48 and 96 h after infection. MS identified 44 altered proteins, including 20 proteins increased in abundance and 24 proteins decreased in abundance, which were found to be involved in cytoskeleton, signal transduction, energy metabolism, host macromolecular biosynthesis, and stress response. Moreover, 22 genes corresponding to the altered proteins were quantified by real-time RT-PCR to examine the transcriptional profiles between infected and uninfected THP-1-derived macrophages. Finally, we mapped the altered pathways and networks using ingenuity pathway analysis, which suggested that the altered protein species were heavily favored germ cell-Sertoli cell junction signaling as the primary pathway. Furthermore, mechanisms of viral exit from host cell and macrophage stimulating protein-recepteur d'origine nantais signaling appeared to be major pathways modulated in infected cells. This study effectively provides useful dynamic protein-related information concerning B. abortus infection in macrophages.

Boundary quantitative characterization of the top-coal limit equilibrium zone in fully mechanized top-coal caving stope along the strike direction of working face.

In the process of fully mechanized top-coal caving mining, the top-coal is affected by mining-induced stress, and the stress varies along the strike direction of working face, so the boundary position of its entering the limit equilibrium state changes accordingly. The determination of the boundary along the strike direction of working face can provide scientific guidance for the stability control of support-surrounding rock in fully mechanized top-coal caving face. Using the research methods of theoretical analysis, physical similarity simulation experiment and numerical simulation experiment, the stress state analysis model of the boundary position of the top-coal limit equilibrium zone under macro-scale conditions was established, the stress state characterization method of the boundary of the top-coal limit equilibrium zone along the strike direction of working face was given, and the quantitative characterization of the boundary of the top-coal limit equilibrium zone along the strike direction of working face was realized by combining with the mining-induced stress path, and the distance relationship between the boundary of the top-coal limit equilibrium zone and the langwall face along the strike direction of working face was revealed. The results show that after critical mining in fully mechanized top-coal caving face, the distance between the boundary of top-coal limit equilibrium zone and the langwall face along the strike direction of working face presents a relationship of increasing from top to bottom. The distance between the top-coal upper boundary and the langwall face was 2.85 m and the distance between the top-coal lower boundary and the langwall face was 5.39 m. The boundary of top-coal limit equilibrium zone along the strike direction of working face was verified by the top-coal elastic-plastic zone boundary and the boundary of the peak position of front abutment pressure in different layers of top-coal. The results show that the quantitative characterization of the top-coal limit equilibrium zone boundary along the strike direction of working face was reasonable. In order to improve mine production efficiency, optimization measures were put forward for hard coal seam and soft coal seam respectively.

Internal stress transfer characteristics of coal-rock medium under concentrated force based on particle flow method.

To solve the problem that the macroscopic deformation and failure of coal-rock medium under external loads are easy to be observed while the internal stress transfer mode and path are unclear. Based on the discrete element idea, the numerical models for pure coal or rock samples and coal-rock combination samples with different lithologies and combination methods under concentrated force are established by PFC2D software. Then the influence of coal or rock strength and combination methods on the internal stress transfer law and distribution evolution characteristics of coal-rock medium are discussed from the perspectives of macroscopic stress and mesoscopic force chain, respectively. The results showed that under concentrated load, the macroscopic stress transfer paths within pure coal or rock samples and coal-rock combination samples are primarily in the form of 'point source radiation'. However, when transferring between coal-rock interfaces, there is a certain interface effect. For pure coal or rock samples, differences in lithology does not change the transfer rules and macro distribution patterns of internal stress, but it can cause changes in internal unit transfer stress value and local area transfer direction. For coal-rock combination samples, the greater the difference in lithology between the two sides of the interface, the more likely the interface effect will occur. In addition, the internal stress transfer is also influenced by the relative stratigraphic relationships of coal and rock. When the stress is transferred from a higher-strength rock to a lower-strength coal mass, the interface effect will be more significant. However, regardless of the combination pattern, the locations where significant stress surges occur are always within the higher strength rock mass near the interface. The findings are helpful to understand the mechanical properties and failure mechanism of mining coal and rock mass, and provide a theoretical basis for the study of the mining-induced mechanical behavior of the floor under the action of the coal pillar.

S-nitrosylation of mixed lineage kinase 3 contributes to its activation after cerebral ischemia.

Previous studies in our laboratory have shown that mixed lineage kinase 3 (MLK3) can be activated following global ischemia. In addition, other laboratories have reported that the activation of MLK3 may be linked to the accumulation of free radicals. However, the mechanism of MLK3 activation remains incompletely understood. We report here that MLK3, overexpressed in HEK293 cells, is S-nitrosylated (forming SNO-MLK3) via a reaction with S-nitrosoglutathione, an exogenous nitric oxide (NO) donor, at one critical cysteine residue (Cys-688). We further show that the S-nitrosylation of MLK3 contributes to its dimerization and activation. We also investigated whether the activation of MLK3 is associated with S-nitrosylation following rat brain ischemia/reperfusion. Our results show that the administration of 7-nitroindazole, an inhibitor of neuronal NO synthase (nNOS), or nNOS antisense oligodeoxynucleotides diminished the S-nitrosylation of MLK3 and inhibited its activation induced by cerebral ischemia/reperfusion. In contrast, 2-amino-5,6-dihydro-6-methyl-4H-1,3-thiazine (an inhibitor of inducible NO synthase) or nNOS missense oligodeoxynucleotides did not affect the S-nitrosylation of MLK3. In addition, treatment with sodium nitroprusside (an exogenous NO donor) and S-nitrosoglutathione or MK801, an antagonist of the N-methyl-D-aspartate receptor, also diminished the S-nitrosylation and activation of MLK3 induced by cerebral ischemia/reperfusion. The activation of MLK3 facilitated its downstream protein kinase kinase 4/7 (MKK4/7)-JNK signaling module and both nuclear and non-nuclear apoptosis pathways. These data suggest that the activation of MLK3 during the early stages of ischemia/reperfusion is modulated by S-nitrosylation and provides a potential new approach for stroke therapy whereby the post-translational modification machinery is targeted.

Target expression of Staphylococcus enterotoxin A from an oncolytic adenovirus suppresses mouse bladder tumor growth and recruits CD3+ T cell.

We recently engineered an oncolytic adenovirus (PPE3-SEA) that expresses the superantigen, Staphylococcus enterotoxin A (SEA), and that has enhanced tumor specificity because the telomerase reverse transcriptase and hypoxia-inducible factor promoters regulate expression of E1A and E1B genes, respectively. Here, we evaluated the PPE3-SEA adenovirus anti-tumor activity against MB49 mouse bladder cancer cell proliferation in vitro and in vivo. PPE3-SEA infection of murine MB49 cells in vitro induced cytopathic effects, and significant expression of SEA mRNA and protein, as measured by RT-PCR and western blot, respectively. Subcutaneous MB29 bladder tumors were established in syngeneic C57BL/6 mice. After 10 days, tumors were injected with either oncolytic virus or PBS. Tumor dimensions were measured on days 1, 3, 5, 7, 9, and 11 post-treatment and tumor volumes were calculated. One of eight PPE3-SEA-treated mice had no tumor by day 9. PPE3-SEA treated group had significantly lower mean tumor volume beginning on day 5 post-treatment (p < 0.01), more fibrous tissue in the tumor, and increased presence of infiltrating CD3+ T cells than those of the control group. Gross appearance and histologic sections from the livers and kidneys of the PPE3-SEA-treated group were similar to those of the control group. In conclusion, oncolytic adenoviruses can provide a novel delivery vehicle for SEA to tumor sites, and PPE3-SEA warrants further study as a potential anti-tumor agent for bladder cancer.

Localized Histoplasma capsulatum osteomyelitis of the fibula in an immunocompetent teenage boy: a case report.

BACKGROUND: Infection of local bone with Histoplasma capsulatum is rare and difficult to diagnosis, and occurs particularly in immunocompetent subjects, who are more likely to be affected by a wide range of organisms. CASE PRESENTATION: An 11-year-old boy presented with localized histoplasmosis osteomyelitis in the left fibula without any evidence of abnormal immunological function or systemic disease. After surgical clearance of the lesion and homologous cancellous bone, the patient was treated orally with voriconazole for 6 months. The patient completely recovered with full function of his left leg during the 5-year follow-up. CONCLUSIONS: Histoplasmosis osteomyelitis can occasionally occur in immunocompetent individuals and can be complete cured by surgical clearance of the lesion and antibiotic treatment.

Research progress in the mechanism of effect of PRP in bone deficiency healing.

Platelet-rich plasma (PRP) therapy is a recently developed technique that uses a concentrated portion of autologous blood to try to improve and accelerate the healing of various tissues. There is a considerable interest in using these PRP products for the treatment used in bone deficiency healing. Because PRP products are safe and easy to prepare and administer, there has been increased attention toward using PRP in numerous clinical settings. The benefits of PRP therapy appear to be promising, and many investigators are exploring the ways in which this therapy can be used in the clinical setting. At present, the molecular mechanisms of bone defect repair studies have focused on three aspects of the inflammatory cytokines, growth factors and angiogenic factors. The role of PRP works mainly through these three aspects of bone repair. The purpose of this paper is to review the current evidence on the mechanism of the effect of PRP in bone deficiency healing.

Forecast for peak infections in the second wave of the Omicron after the adjustment of zero-COVID policy in the mainland of China.

On December 7, 2022, the Chinese government optimized the current epidemic prevention and control policy, and no longer adopted the zero-COVID policy and mandatory quarantine measures. Based on the above policy changes, this paper establishes a compartment dynamics model considering age distribution, home isolation and vaccinations. Parameter estimation was performed using improved least squares and Nelder-Mead simplex algorithms combined with modified case data. Then, using the estimated parameter values to predict a second wave of the outbreak, the peak of severe cases will reach on 8 May 2023, the number of severe cases will reach 206,000. Next, it is proposed that with the extension of the effective time of antibodies obtained after infection, the peak of severe cases in the second wave of the epidemic will be delayed, and the final scale of the disease will be reduced. When the effectiveness of antibodies is 6 months, the severe cases of the second wave will peak on July 5, 2023, the number of severe cases is 194,000. Finally, the importance of vaccination rates is demonstrated, when the vaccination rate of susceptible people under 60 years old reaches 98%, and the vaccination rate of susceptible people over 60 years old reaches 96%, the peak of severe cases in the second wave of the epidemic will be reached on 13 July 2023, when the number of severe cases is 166,000.

Study of CFD-DEM on the Impact of the Rolling Friction Coefficient on Deposition of Lignin Particles in a Single Ceramic Membrane Pore.

The discrete element method coupled with the computational fluid dynamic (CFD-DEM) method is effective for studying the micro-flow process of lignin particles in ceramic membranes. Lignin particles may exhibit various shapes in industry, so it is difficult to model their real shapes in CFD-DEM coupled solutions. Meanwhile, the solution of non-spherical particles requires a very small time-step, which significantly lowers the computational efficiency. Based on this, we proposed a method to simplify the shape of lignin particles into spheres. However, the rolling friction coefficient during the replacement was hard to be obtained. Therefore, the CFD-DEM method was employed to simulate the deposition of lignin particles on a ceramic membrane. Impacts of the rolling friction coefficient on the deposition morphology of the lignin particles were analyzed. The coordination number and porosity of the lignin particles after deposition were calculated, based on which the rolling friction coefficient was calibrated. The results indicated that the deposition morphology, coordination number, and porosity of the lignin particles can be significantly affected by the rolling friction coefficient and slightly influenced by that between the lignin particles and membranes. When the rolling friction coefficient among different particles increased from 0.1 to 3.0, the average coordination number decreased from 3.96 to 2.73, and the porosity increased from 0.65 to 0.73. Besides, when the rolling friction coefficient among the lignin particles was set to 0.6-2.4, the spherical lignin particles could replace the non-spherical particles.

Glioblastoma cellular MAP4K1 facilitates tumor growth and disrupts T effector cell infiltration.

MAP4K1 has been identified as a cancer immunotherapy target. Whether and how cancer cell-intrinsic MAP4K1 contributes to glioblastoma multiforme (GBM) progression remains unclear. We found that MAP4K1 was highly expressed in the glioma cells of human GBM specimens. High levels of MAP4K1 mRNA were prevalent in IDH-WT and 1p/19q non-codeletion gliomas and correlated with poor prognosis of patients. MAP4K1 silencing inhibited GBM cell proliferation and glioma growth. Transcriptome analysis of GBM cells and patient samples showed that MAP4K1 modulated cytokine‒cytokine receptor interactions and chemokine signaling pathway, including IL-18R and IL-6R Importantly, MAP4K1 loss down-regulated membrane-bound IL-18R/IL-6R by inhibiting the PI3K-AKT pathway, whereas MAP4K1 restoration rescued this phenotype and therefore GBM cell proliferation. MAP4K1 deficiency abolished GBM cell pro-proliferation responses to IL-18, suggesting an oncogenic role of MAP4K1 via the intrinsic IL-18/IL-18R pathway. In addition, GBM cell-derived MAP4K1 impaired T-cell migration and reduced CD8+ T-cell infiltration in mouse glioma models. Together, our findings provide novel insight into the pathological significance of GBM cell-intrinsic MAP4K1 in driving tumor growth and immune evasion by remodeling cytokine-chemokine networks.

Proteome dynamics in primary target organ of infectious bursal disease virus.

Viruses induce dramatic changes in target tissue during pathogenesis, including host cellular responses that either limit or support the pathogen. The infectious bursal disease virus (IBDV) targets primarily the bursa of Fabricius (BF) of chickens, causing severe immunodeficiency. Here, we characterized the cellular proteome changes of the BF caused by IBDV replication in vivo using 2DE followed MALDI-TOF MS identification. Comparative analysis of multiple 2DE gels revealed that the majority of protein expression changes appeared between 24 and 96 h after IBDV infection. MS identified 54 altered cell proteins, 12 of which were notably upregulated by IBDV infection. Meanwhile, the other 42 cellular proteins were considerably suppressed by IBDV infection and are involved in protein degradation, energy metabolism, stress response, host macromolecular biosynthesis, and transport process. The upregulation of ß-actin and downregulation of dynamin during IBDV infection were also confirmed by Western blot and immunofluorescence analysis. These altered protein expressions provide a response profile of chicken BF to virulent IBDV infection. Further functional study on these altered proteins may lead to better understanding of pathogenic mechanisms of virulent IBDV infection and to new potential therapeutic targets.

Activation of GluR6-containing kainate receptors induces ubiquitin-dependent Bcl-2 degradation via denitrosylation in the rat hippocampus after kainate treatment.

We previously showed that Bcl-2 (B-cell lymphoma 2) is down-regulated in a kainate (KA)-induced rat epileptic seizure model. The underlying mechanism had remained largely unknown, but we here report for the first time that denitrosylation and ubiquitination are involved. Our results show that the S-nitrosylation levels of Bcl-2 are down-regulated after KA injection and that the GluR6 (glutamate receptor 6) antagonist NS102 can inhibit the denitrosylation of Bcl-2. Moreover, the ubiquitin-dependent degradation of Bcl-2 was found to be promoted after KA treatment, which could be suppressed by the proteasome inhibitor MG132 and the NO donors, sodium nitroprusside and S-nitrosoglutathione. In addition, experiments based on siRNA transfections were performed in the human SH-SY5Y neuroblastoma cell line to verify that the stability of Bcl-2 is causal to neuronal survival. At the same time, it was found that the exogenous NO donor GSNO could protect neurons when Bcl-2 is targeted. Subsequently, these mechanisms were morphologically validated by immunohistochemistry, cresyl violet staining, and in situ TUNEL staining to analyze the expression of Bcl-2 as well as the survival of CA1 and CA3/DG pyramidal neurons. NS102, GSNO, sodium nitroprusside, and MG132 contribute to the survival of CA1 and CA3/DG pyramidal neurons by attenuating Bcl-2 denitrosylation. Taken together, our data reveal that Bcl-2 ubiquitin-dependent degradation is induced by Bcl-2 denitrosylation during neuronal apoptosis after KA treatment.