Spatiotemporal Characterization of Microstructure Morphology, Mechanical Properties and Bone Remodeling of Rat Tibia Under Uniaxial Compressive Overload Loading.

Bone tissue is subjected to increased mechanical stress during high-intensity work. Inadequate bone remodeling reparability can result in the continuous accumulation of microdamage, leading to stress fractures. The aim of this work was to investigate the characteristics and repair mechanisms of tibial microdamage under several degrees of overload. Also, we aimed at better understanding the effects of overload on the multi-scale structure and mechanical properties of bone. Sixty 5-month female rats were divided into three groups with different time points. Micro-CT was used to evaluate the three-dimensional microstructure, and three-point bending, quasi-static fracture toughness and creep mechanical test were carried out to evaluate the mechanical properties. SEM was used to observe the morphological characteristics of fracture surfaces. Section staining was used to count the microdamage parameters and numbers of osteoblasts and osteoclasts. The microarchitectures of cancellous and cortical bones in the three overload groups showed different degrees of damage. Overload led to a messy crystal structure of cortical bone, with slender microcracks mixed in, and a large number of broken fibers of cancellous bone. The properties associated with the elastic plasticity, fracture toughness, and viscoelasticity of cortical bone reduced in three groups, with that corresponding to day 30 presenting the highest damage. The accumulation of microdamage mainly occurred in the first 14 days, that is, the crack density peaked on day 14. Peak-targeted bone remodeling of cortical and cancellous bones occurred mainly between days 14 and 30. The influence of overload mechanical environment on bone quality at different time points was deeply investigated, which is of great significance for the etiology and treatment of stress fractures.

Nanoporous cobalt-doped AlNi3/NiO architecture for high performing hydrogen evolution at high current densities.

Engineering platinum-free catalysts for hydrogen evolution reaction (HER) with high activity and stability is essential for electrochemical hydrogen production. In this paper, we report the synthesis of cobalt-doped AlNi3/NiO (Co-AlNi3/NiO) electrode with three-dimensional nanoporous structure via chemical dealloying method. Density functional theory (DFT) calculations reveal that Co-AlNi3/NiO can accelerate water adsorption / dissociation and optimize adsorption-desorption energies of H* intermediates, thus improving the intrinsic HER activity. Both the introduction of Co and Al can efficiently ameliorate the electronic density around Ni sites of NiO and AlNi3, which can effectively reduce the energy barrier towards Volmer-Heyrovsky reaction and thus synergistically promote the hydrogen evolution. Benefiting from the large electrochemical active surface area, high electrical conductivity and electronic effect, the nanoporous Co-AlNi3/NiO catalyst exhibits remarkable HER activity with an overpotential of 73 mV at a current density of 10 mA cm-2 in alkaline condition, outperforming most of the reported non-precious metal catalysts. The nanoporous Co-AlNi3/NiO catalyst can operate continuously over 1000 h at high current densities with a robust stability. This work provides a new vision for the development of low-cost and efficient electrocatalysts for energy conversion applications.

Dynamic altruistic cooperation within breast tumors.

BACKGROUND: Social behaviors such as altruism, where one self-sacrifices for collective benefits, critically influence an organism's survival and responses to the environment. Such behaviors are widely exemplified in nature but have been underexplored in cancer cells which are conventionally seen as selfish competitive players. This multidisciplinary study explores altruism and its mechanism in breast cancer cells and its contribution to chemoresistance. METHODS: MicroRNA profiling was performed on circulating tumor cells collected from the blood of treated breast cancer patients. Cancer cell lines ectopically expressing candidate miRNA were used in co-culture experiments and treated with docetaxel. Ecological parameters like relative survival and relative fitness were assessed using flow cytometry. Functional studies and characterization performed in vitro and in vivo include proliferation, iTRAQ-mass spectrometry, RNA sequencing, inhibition by small molecules and antibodies, siRNA knockdown, CRISPR/dCas9 inhibition and fluorescence imaging of promoter reporter-expressing cells. Mathematical modeling based on evolutionary game theory was performed to simulate spatial organization of cancer cells. RESULTS: Opposing cancer processes underlie altruism: an oncogenic process involving secretion of IGFBP2 and CCL28 by the altruists to induce survival benefits in neighboring cells under taxane exposure, and a self-sacrificial tumor suppressive process impeding proliferation of altruists via cell cycle arrest. Both processes are regulated concurrently in the altruists by miR-125b, via differential NF-κB signaling specifically through IKKß. Altruistic cells persist in the tumor despite their self-sacrifice, as they can regenerate epigenetically from non-altruists via a KLF2/PCAF-mediated mechanism. The altruists maintain a sparse spatial organization by inhibiting surrounding cells from adopting the altruistic fate via a lateral inhibition mechanism involving a GAB1-PI3K-AKT-miR-125b signaling circuit. CONCLUSIONS: Our data reveal molecular mechanisms underlying manifestation, persistence and spatial spread of cancer cell altruism. A minor population behave altruistically at a cost to itself producing a collective benefit for the tumor, suggesting tumors to be dynamic social systems governed by the same rules of cooperation in social organisms. Understanding cancer cell altruism may lead to more holistic models of tumor evolution and drug response, as well as therapeutic paradigms that account for social interactions. Cancer cells constitute tractable experimental models for fields beyond oncology, like evolutionary ecology and game theory.

Dealloying-derived nanoporous Sn-doped copper with prior selectivity toward formate for CO2 electrochemical reduction.

We report nanoporous Cu-Sn catalysts fabricated by chemically dealloying rapid solidified Al-Cu-Sn alloys for the CO2RR. The np-Cu11Sn1 catalyst exhibits a three-dimensional interconnected ligament-channel network structure, which can efficiently convert CO2 to formate with a Faradaic efficiency (FE) of 72.1% at -1.0 V (vs. RHE).

Chronic exposure to yttrium induced cell apoptosis in the testis by mediating Ca2+/IP3R1/CaMKII signaling.

Introduction: Environmental pollutants, such as rare earth elements, affect human health and particularly induce reproductive system injury. Yttrium (Y), one of the most widely used heavy rare earth elements, has been reported the cytotoxicity. However, the biological effects of Y3+ in the human body are largely unknown. Methods: To further investigate the effects of Y on the reproductive system, in vivo (rat models) and in vitro studies were performed. Histopathological and immunohistochemical examination were conducted, and western blotting assays were performed to detect the protein expression. TUNEL/DAPI staining were used to detect cell apoptosis, and the intracellular calcium concentrations were also determined. Results: Long-term exposure to YCl3 in rats produced significant pathological changes. YCl3 treatment could induce cell apoptosis in vivo and in vitro. In addition, YCl3 enhanced the concentration of cytosolic Ca2+ and up regulated the expression of IP3R1/CaMKII axis in Leydig cells. However, inhibition of IP3R1 and CaMKII with 2-APB and KN93, respectively, could reverse these effects. Conclusion: Long-term exposure to yttrium could induce testicular injury by stimulating cell apoptosis, which might be associated with activation of Ca2+/IP3R1/CaMKII axis in Leydig cells.

Recent Progresses in Electrochemical DNA Biosensors for SARS-CoV-2 Detection.

Coronavirus disease 19 (COVID-19) is still a major public health concern in many nations today. COVID-19 transmission is now controlled mostly through early discovery, isolation, and therapy. Because of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the contributing factor to COVID-19, establishing timely, sensitive, accurate, simple, and budget detection technologies for the SARS-CoV-2 is urgent for epidemic prevention. Recently, several electrochemical DNA biosensors have been developed for the rapid monitoring and detection of SARS-CoV-2. This mini-review examines the latest improvements in the detection of SARS-COV-2 utilizing electrochemical DNA biosensors. Meanwhile, this mini-review summarizes the problems faced by the existing assays and puts an outlook on future trends in the development of new assays for SARS-CoV-2, to provide researchers with a borrowing role in the generation of different assays.

The adaptive response of rat tibia to different levels of peak strain and durations of experiment.

The osteogenic response of bone to compressive load is affected by peak strain and duration of experiment, however, combined effect of peak load and duration of experiment on the rat tibia axial loading model remains unclear. In this study, rat tibia axial loading models with different levels of peak strains and durations of experiments were established (peak loads: 10 N, 20 N and 40 N, experimental duration: 2 weeks and 4 weeks). Microcomputer tomography scanning (Micro-CT), compression mechanical test and bone tissue alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) staining were used to investigate the effects of cyclic loading with different levels of peak strains and durations of experiments on osteogenic response of tibia in adult female Sprague-Dawley (SD) rats. This experiment demonstrates that high-level strain can significantly stimulate the osteogenic response of cancellous and cortical bones in a short period of time. However, under mid-level strain, prolonging the experiment time can significantly improve the microsturcture and macromechanical properties of bone, increase the number of osteoblasts, and achieve the goal of improving bone quality. In this study, two loading schemes of mid-level-long-term and high-level-short-term were analyzed, and the mechanical response of the tibia under two different loading schemes was investigated. It provided a theoretical basis for further promoting the study of improving human bone quality and preventing aging-related bone diseases through mechanical stimulation.

Identification of a glycolysis-related gene signature for predicting pancreatic cancer survival.

Background: Pancreatic cancer (PC) is one of the most common malignant tumors of the digestive tract. Its clinical symptoms are obscure and atypical. It is difficult to diagnose and treat. Tumor cells mainly obtain energy through glycolysis to promote their growth. Inhibiting glycolysis can inhibit proliferation and kill tumor cells. Methods: Using bioinformatics method, we investigate the relationships between glycolysis-related genes and PC tumor samples' epidemiologic information comprehensively. Results: Different expression levels of 27 genes were identified. Using bioinformatics methods, we plotted two subgroup curves based on glycolysis-related gene expression level. Potential predictive genes were screened and their prognostic values were analyzed. Survival among high-risk group and low risk group had significant difference. Receiver operating characteristic (ROC) curve analysis indicated that area under curve (AUC) of 10 genes was greater than 0.8. These genes could be used for clinical diagnosis and prediction for PC. Two potential predictors [Kinesin Family Member 20A (KIF20A) and MET Proto-Oncogene, Receptor Tyrosine Kinase (MET)] that met the independent predictive value were selected. In univariate analysis, we screened out 3 regulators MET, protein kinase CAMP-activated catalytic subunit alpha (PRKACA) and KIF20A. According to the 3 regulatory factors, the prognostic signals of PC were constructed, by which the samples with good prognosis and poor prognosis can be clearly distinguished independently of potential confounding factors. Conclusions: Our results indicate that for PC, glycolysis -related genes could be promising therapeutic targets or prognostic indicators.

Systematic Characterization of Novel Immune Gene Signatures Predicts Prognostic Factors in Hepatocellular Carcinoma.

Background: The prognosis of patients with hepatocellular carcinoma (HCC) is negatively affected by the lack of effective prognostic indicators. The change of tumor immune microenvironment promotes the development of HCC. This study explored new markers and predicted the prognosis of HCC patients by systematically analyzing immune characteristic genes. Methods: Immune-related genes were obtained, and the differentially expressed immune genes (DEIGs) between tumor and para-cancer samples were identified and analyzed using gene expression profiles from TCGA, HCCDB, and GEO databases. An immune prognosis model was also constructed to evaluate the predictive performance in different cohorts. The high and low groups were divided based on the risk score of the model, and different algorithms were used to evaluate the tumor immune infiltration cell (TIIC). The expression and prognosis of core genes in pan-cancer cohorts were analyzed, and gene enrichment analysis was performed using clusterProfiler. Finally, the expression of the hub genes of the model was validated by clinical samples. Results: Based on the analysis of 730 immune-related genes, we identified 64 common DEIGs. These genes were enriched in the tumor immunologic related signaling pathways. The first 15 genes were selected using RankAggreg analysis, and all the genes showed a consistent expression trend across multi-cohorts. Based on lasso cox regression analysis, a 5-gene signature risk model (ATG10, IL18RAP, PRKCD, SLC11A1, and SPP1) was constructed. The signature has strong robustness and can stabilize different cohorts (TCGA-LIHC, HCCDB18, and GSE14520). Compared with other existing models, our model has better performance. CIBERSORT was used to assess the landscape maps of 22 types of immune cells in TCGA, GSE14520, and HCCDB18 cohorts, and found a consistent trend in the distribution of TIIC. In the high-risk score group, scores of Macrophages M1, Mast cell resting, and T cells CD8 were significantly lower than those of the low-risk score group. Different immune expression characteristics, lead to the different prognosis. Western blot demonstrated that ATG10, PRKCD, and SPP1 were highly expressed in cancer tissues, while IL18RAP and SLC11A1 expression in cancer tissues was lower. In addition, IL18RAP has a highly positive correlation with B cell, macrophage, Neutrophil, Dendritic cell, CD8 cell, and CD4 cell. The SPP1, PRKCD, and SLC11A1 genes have the strongest correlation with macrophages. The expression of ATG10, IL18RAP, PRKCD, SLC11A1, and SPP1 genes varies among different immune subtypes and between different T stages. Conclusion: The 5-immu-gene signature constructed in this study could be utilized as a new prognostic marker for patients with HCC.

[Design of new gradient scaffolds based on triply periodic minimal surfaces and study on its mechanical, permeability and tissue differentiation characteristics].

In order to establish a bone scaffold with good biological properties, two kinds of new gradient triply periodic minimal surfaces (TPMS) scaffolds, i.e., two-way linear gradient G scaffolds (L-G) and D, G fusion scaffold (N-G) were designed based on the gyroid (G) and diamond (D)-type TPMS in this study. The structural mechanical parameters of the two kinds of scaffolds were obtained through the compressive simulation. The flow property parameters were also obtained through the computational fluid dynamics (CFD) simulation in this study, and the permeability of the two kinds of scaffolds were calculated by Darcy's law. The tissue differentiation areas of the two kinds of scaffolds were calculated based on the tissue differentiation theory. The results show that L-G scaffold has a better mechanical property than the N-G scaffold. However, N-G scaffold is better than the L-G scaffold in biological properties such as permeability and cartilage differentiation areas. The modeling processes of L-G and N-G scaffolds provide a new insight for the design of bone scaffold. The simulation in this study can also give reference for the prediction of osseointegration after the implantation of scaffold in the human body.

Systematic Analysis of an Invasion-Related 3-Gene Signature and Its Validation as a Prognostic Model for Pancreatic Cancer.

BACKGROUND: Pancreatic adenocarcinoma (PAAD) is a malignant tumor of the digestive system that is associated with a poor prognosis in patients owing to its rapid progression and high invasiveness. METHODS: Ninety-seven invasive-related genes obtained from the CancerSEA database were clustered to obtain the molecular subtype of pancreatic cancer based on the RNA-sequencing (RNA-seq) data of The Cancer Genome Atlas (TCGA). The differentially expressed genes (DEGs) between subtypes were obtained using the limma package in R, and the multi-gene risk model based on DEGs was constructed by Lasso regression analysis. Independent datasets GSE57495 and GSE62452 were used to validate the prognostic value of the risk model. To further explore the expression of the hub genes, immunohistochemistry was performed on PAAD tissues obtained from a large cohort. RESULTS: The TCGA-PAAD samples were divided into two subtypes based on the expression of the invasion-related genes: C1 and C2. Most genes were overexpressed in the C1 subtype. The C1 subtype was mainly enriched in tumor-related signaling pathways, and the prognosis of patients with the C1 subtype was significantly worse than those with the C2 subtype. A 3-gene signature consisting of LY6D, BCAT1, and ITGB6 based on 538 DEGs between both subtypes serves as a stable prognostic marker in patients with pancreatic cancer across multiple cohorts. LY6D, BCAT1, and ITGB6 were over-expressed in 120 PAAD samples compared to normal samples. CONCLUSIONS: The constructed 3-gene signature can be used as a molecular marker to assess the prognostic risk in patients with PAAD.

Contribution of Fc-dependent cell-mediated activity of a vestigial esterase-targeting antibody against H5N6 virus infection.

The highly pathogenic avian influenza A (H5N6) virus has caused sporadic human infections with a high case fatality rate. Due to the continuous evolution of this virus subtype and its ability to transmit to humans, there is an urgent need to develop effective antiviral therapeutics. In this study, a murine monoclonal antibody 9F4 was shown to display broad binding affinity against H5Nx viruses. Furthermore, 9F4 can neutralize H5N6 pseudotyped particles and prevent entry into host cells. Additionally, ADCC/ADCP deficient L234A, L235A (LALA) and CDC deficient K322A mutants were generated and displayed comparable binding affinity and neutralizing activity as wild type 9F4 (9F4-WT). Notably, 9F4-WT, 9F4-LALA and 9F4-K322A exhibit in vivo protective efficacies against H5N6 infections in that they were able to reduce viral loads in mice. However, only 9F4-WT and 9F4-K322A but not 9F4-LALA were able to reduce viral pathogenesis in H5N6 challenged mice. Furthermore, depletion of phagocytic cells in mice lungs nullifies 9F4-WT's protection against H5N6 infections, suggesting a crucial role of the host's immune cells in 9F4 antiviral activity. Collectively, these findings reveal the importance of ADCC/ADCP function for 9F4-WT protection against HPAIV H5N6 and demonstrate the potential of 9F4 to confer protection against the reassortant H5-subtype HPAIVs.

Effects of treadmill with different intensities on bone quality and muscle properties in adult rats.

BACKGROUND: Bone is a dynamically hierarchical material that can be divided into length scales of several orders of magnitude. Exercise can cause bone deformation, which in turn affects bone mass and structure. This study aimed to study the effects of treadmill running with different intensities on the long bone integrity and muscle biomechanical properties of adult male rats. METHODS: Forty-eight 5-month-old male SD rats were randomly divided into 4 groups: i.e., sedentary group (SED), exercise with speed of 12 m/min group (EX12), 16 m/min group (EX16), and 20 m/min group (EX20). The exercise was carried out for 30 min every day, 5 days a week for 4 weeks. The femurs were examined using three-point bending test, microcomputer tomography scanning and nanoindentation test; the soleus muscle was dissected for tensile test; ALP and TRACP concentrations were measured by serum analysis. RESULTS: The failure load was significantly increased by the EX12 group, whereas the elastic modulus was not significantly changed. The microstructure and mineral densities of the trabecular and cortical bone were significantly improved by the EX12 group. The mechanical properties of the soleus muscle were significantly increased by treadmill exercise. Bone formation showed significant increase by the EX12 group. Statistically higher nanomechanical properties of cortical bone were detected in the EX12 group. CONCLUSION: The speed of 12 m/min resulted in significant changes in the microstructure and biomechanical properties of bone; besides, it significantly increased the ultimate load of the soleus muscle. The different intensities of treadmill running in this study provide an experimental basis for the selection of exercise intensity for adult male rats.

Combination of gemcitabine and erlotinib inhibits recurrent pancreatic cancer growth in mice via the JAK-STAT pathway.

Compared to single gemcitabine treatment, the combination of gemcitabine and erlotinib has shown effective response in patients with locally advanced or metastatic pancreatic cancer. However, the combination therapy has not proven effective in patients with pancreatic cancer after R0 or R1 resection. In the present study, a nude mice model of orthotopic xenotransplantation after tumor resection was established using pancreatic cancer cell lines, BxPC-3 and PANC­1. Mice were divided in four groups (each with n=12) and were treated as follows: the control group received a placebo via intraperitoneal injection (i.p.), while the other three groups were treated with gemcitabine (50 mg/kg i.p., twice a week), erlotinib (50 mg/kg oral gavage, once every three days), and combined treatment of gemcitabine and erlotinib, respectively. The treatment lasted for 21 days, after which all mice were sacrificed and tumors were examined ex vivo. We determined that the combination of gemcitabine and erlotinib inhibited recurrent tumor growth and induced apoptosis in vivo by downregulating phosphorylation levels of JAKs and STATs, which in turn downregulated the downstream proteins HIF­1α and cyclin D1, and upregulated caspase­9 and caspase­3 expression. To sum up, the combination of gemcitabine with erlotinib was effective in treating patients with pancreatic cancer after R0 or R1 resection.

[Herbs for calming liver and suppressing yang in treatment of hyperthyroidism with hyperactive liver yang: herbal effects on lymphocyte protein expression].

OBJECTIVE: To observe the herbal effects on hyperthyroidism patients with syndrome of hyperactivity of liver-Yang by method for calming the liver and suppressing Yang and investigate its effects on the lymphocyte protein expression. This approach may lay a foundation for the further investigation of the curative mechanisms of calming the liver and suppressing Yang treatment. METHOD: A total of 48 hyperthyroidism patients with syndrome of hyperactivity of liver-Yang were randomly divided into treatment group and control group. The treatment group was treated by method for calming the liver and suppressing Yang in accordance with traditional Chinese medicine (TCM) and the control group with thiamazole tablets for three periods of treatment The therapeutic effects, the score of TCM symptom, electrocardiogram (P wave), thyroid hormones and ultrasound were observed in both groups before and after the treatment. The side effects in the treatment course were observed in both groups. The level of differential protein expression was analyzed by two-dimensional electrphoresis and matrix assisted laser desorption/ionizaton time-of-flight mass spectrometry. RESULT: The treatment group has the effect on stepping down the heart rate, cutting down the P wave amplitude changes, regulating the level of thyroid hormones and decreasing the volume of thyromegaly. There are not statistically significant between the treatment group and control group. However, the treatment group has obviously better effect on regulating TCM symptom and decreasing the side reaction than the control group (P<0.05). There are not statistically significant on the total effective between the treatment group and control group. The average spots in lymphocyte for normal people, before and after treating hyperthyroidism patients with syndrome of hyperactivity of liver-Yang were (429 +/- 31), (452 +/- 28) and (437 +/- 36) spots respectively. Eight down-regulated protein expressions and 11 up-regulated protein expressions were obtained in the hyperthyroidism patients with syndrome of hyperactivity of liver-Yang and normal people. Five strengthened expressions of protein were also obtained in 8 down-regulated expressions of protein and 8 lower expressions of protein in 11 up-regulated expressions of protein before and after treating the migraine patients with syndrome of hyperactivity of liver-Yang. Ten of the total 8 differential protein spots were successfully identified by MALDI-TOF-MS. The functions of these proteins were involved in metabolism associated, transportation, antioxidation, sigal transduction and immume associated protein, etc. according to information provided by NCBI and MSDB database. CONCLUSION: In this study, the TCM complex prescription with herbs for calming the liver and suppressing Yang can regulate the thyroid hormones, improves TCM symptoms, and decrease the adverse reaction. It can possibly regulate lymphocyte protein expression.