Bone Tumor Suppression in Rabbits by Hyperthermia below the Clinical Safety Limit Using Aligned Magnetic Bone Cement.

Demonstrating highly efficient alternating current (AC) magnetic field heating of nanoparticles in physiological environments under clinically safe field parameters has remained a great challenge, hindering clinical applications of magnetic hyperthermia. In this work, exceptionally high loss power of magnetic bone cement under the clinical safety limit of AC field parameters, incorporating direct current field-aligned soft magnetic Zn0.3 Fe2.7 O4 nanoparticles with low concentration, is reported. Under an AC field of 4 kA m-1 at 430 kHz, the aligned bone cement with 0.2 wt% nanoparticles achieves a temperature increase of 30 °C in 180 s. This amounts to a specific loss power value of 327 W gmetal-1 and an intrinsic loss power of 47 nHm2 kg-1 , which is enhanced by 50-fold compared to randomly oriented samples. The high-performance magnetic bone cement allows for the demonstration of effective hyperthermia suppression of tumor growth in the bone marrow cavity of New Zealand White Rabbits subjected to rapid cooling due to blood circulation, and significant enhancement of survival rate.

Highly interconnected inverse opal extracellular matrix scaffolds enhance stem cell therapy in limb ischemia.

The therapeutic effectiveness of cell transplantation in treatment of diseases and injuries is often limited by low cell retention, survivability, and engraftment. Extracellular matrix (ECM)-derived scaffolds are capable of controlling cell responses, thereby offering potential solutions to current challenges associated with cell therapy. However, it remains a technical challenge to produce ECM scaffolds with highly interconnected porous structure specifically required for cell transplantation. Here, we developed inverse opal porous extracellular matrix (ioECM) scaffolds through subcutaneous implantation of sacrificial templates assembled from polymer microspheres, followed by removal of the microsphere template and cellular content. Such highly interconnected porous ioECM scaffolds supported the anchorage, survival, viability, anti-apoptotic and paracrine activities of rat bone marrow mesenchymal stem cells (BMSCs), which further promoted endothelial cell migration and tube formation and viability. Upon transplantation into nude mouse critical limb ischemic model, ioECM promoted the engraftment of laden BMSCs, facilitated interconnected vascular network formation with accelerated recovery of blood perfusion and inhibited muscle atrophy and fibrosis. Our study demonstrates a unique strategy to engineer highly porous yet well-interconnected ECM scaffolds specifically for cell transplantation with marked improvement of survivability and vascularization, which offers an essential step toward the success of cell therapy and regenerative medicine. STATEMENT OF SIGNIFICANCE: Cell-based therapy has a good developing foreground applied in a variety of tissue regeneration. Extracellular matrix (ECM) scaffolds is an optimal choice for cell delivery duo to its superior biocompatibility and favorable immune responses. However, the current ECM scaffolds lacking of the controllable pore structure restrict the cell delivery efficiency and therapeutic outcome. Here, we fabricated highly interconnected inverse opal extracellular matrix (ioECM) scaffolds, which can enhance the effect of stem cell therapy in limb ischemic model by improving the survival, viability, and paracrine activities of stem cells. Our study provides reference value for the design and fabrication of ECM based biomaterials for cell transplantation.

Maximizing Specific Loss Power for Magnetic Hyperthermia by Hard-Soft Mixed Ferrites.

Maximized specific loss power and intrinsic loss power approaching theoretical limits for alternating-current (AC) magnetic-field heating of nanoparticles are reported. This is achieved by engineering the effective magnetic anisotropy barrier of nanoparticles via alloying of hard and soft ferrites. 22 nm Co0.03 Mn0.28 Fe2.7 O4 /SiO2 nanoparticles reach a specific loss power value of 3417 W g-1metal at a field of 33 kA m-1 and 380 kHz. Biocompatible Zn0.3 Fe2.7 O4 /SiO2 nanoparticles achieve specific loss power of 500 W g-1metal and intrinsic loss power of 26.8 nHm2 kg-1 at field parameters of 7 kA m-1 and 380 kHz, below the clinical safety limit. Magnetic bone cement achieves heating adequate for bone tumor hyperthermia, incorporating an ultralow dosage of just 1 wt% of nanoparticles. In cellular hyperthermia experiments, these nanoparticles demonstrate high cell death rate at low field parameters. Zn0.3 Fe2.7 O4 /SiO2 nanoparticles show cell viabilities above 97% at concentrations up to 500 µg mL-1 within 48 h, suggesting toxicity lower than that of magnetite.

Osteocytogenesis: Roles of Physicochemical Factors, Collagen Cleavage, and Exogenous Molecules.

Osteocytes, the most abundant cell type in mammalian bone, are generally considered as the terminally differentiated cells of osteoblasts that are progressively self-buried or passively embedded in bone matrix. Emerging evidence reveals the essential functions of osteocytes in bone homeostasis and mechanotransduction. However, our knowledge on osteocytes, especially their formation, remains scarce. In this regard, the current review mainly focuses on several key factors that drive the osteocytic differentiation of osteoblasts, that is, osteocytogenesis. Available literature has demonstrated the involvement of physicochemical factors such as matrix composition, oxygen tension, and mechanical stress in the osteoblast-to-osteocyte transition. During cell migration and matrix remodeling, the matrix metalloproteinase-dependent collagen cleavage would play an "active" role in maturation and maintenance of the osteocytes. Besides, some in vitro methodologies are also established to induce the transformation of osteoblastic cell lines and primary mesenchymal cells to preosteocytes through cell transfection or addition of exogenous molecules (e.g., fibroblast growth factor-2, retinoic acid), which could potentiate the effort to form functional bone substitutes through elevated osteocytogenesis. Thus, advances of new technologies would enable comprehensive and in-depth understanding of osteocytes and their development, which in turn help promote the research on osteocyte biology and osteopathology.

The GhmiR157a-GhSPL10 regulatory module controls initial cellular dedifferentiation and callus proliferation in cotton by modulating ethylene-mediated flavonoid biosynthesis.

MicroRNAs (miRNAs) modulate many biological processes through inactivation of specific mRNA targets such as those encoding transcription factors. A delicate spatial/temporal balance between specific miRNAs and their targets is central to achieving the appropriate biological outcomes. Somatic embryogenesis in cotton (Gossypium hirsutum), which goes through initial cellular dedifferentiation, callus proliferation, and somatic embryo development, is of great importance for both fundamental research and biotechnological applications. In this study, we characterize the function of the GhmiR157a-GhSPL10 miRNA-transcription factor module during somatic embryogenesis in cotton. We show that overexpression of GhSPL10, a target of GhmiR157a, increases free auxin and ethylene content and expression of associated signaling pathways, activates the flavonoid biosynthesis pathway, and promotes initial cellular dedifferentiation and callus proliferation. Inhibition of expression of the flavonoid synthesis gene F3H in GhSPL10 overexpression lines (35S:rSPL10-7) blocked callus initiation, while exogenous application of several types of flavonol promoted callus proliferation, associated with cell cycle-related gene expression. Inhibition of ethylene synthesis by aminoethoxyvinylglycine treatment in the 35S:rSPL10-7 line severely inhibited callus initiation, while activation of ethylene signaling through 1-aminocyclopropane 1-carboxylic acid treatment, EIN2 overexpression, or inhibition of the ethylene negative regulator CTR1 by RNA interference promoted flavonoid-related gene expression and flavonol accumulation. These results show that an up-regulation of ethylene signaling and the activation of flavonoid biosynthesis in GhSPL10 overexpression lines were associated with initial cellular dedifferentiation and callus proliferation. Our results demonstrate the importance of a GhmiR157a-GhSPL10 gene module in regulating somatic embryogenesis via hormonal and flavonoid pathways.

Application of sequential (18)F-FDG PET/CT scans for concurrent chemoradiotherapy of non-surgical squamous cell esophageal carcinoma.

PURPOSE: To explore the values of sequential (18)F-FDG PET/CT scanning in patients with non-surgical esophageal squamous cell carcinoma (ESCC) who received concurrent chemoradiotherapy (CCRT). METHODS: Twenty-eight patients with pathologically confirmed stage I-IV ESCC and who received definitive CCRT were prospectively enrolled into this trial. The (18)F-FDG PET/CT scans were performed four times. The maximum standardized uptake values (SUVmax) of each scanning were named as SUVmaxpet1, SUVmaxpet2, SUVmaxpet3, and SUVmaxpet4, respectively. The tumor volume with SUV greater than 40% of SUVmax was named as metabolic tumor volume (MTV). Follow-up investigation of patients was performed to record progression-free survival (PFS), relapse-free survival (RFS), and overall survival time (OS). RESULTS: The average value of MTV before treatment is 19.3 ml. The average value of SUVmax at four time points was 13.0 ± 7.4, 6.4 ± 3.2, 4.7 ± 1.9, and 3.4 ±1.8, respectively. Median follow-up time was 18.5 months (range 5-40). There was statistically significant difference in ΔR14 ((SUVmaxpet1- SUVmaxpet4) / SUVmaxpet1). Multivariate Cox regression survival analysis indicated that the MTV was an independent prognostic factor for PFS and RFS (HR = 1.13 and 1.14, respectively) before treatment. CONCLUSION: In CCRT of non-surgical ESCC, MTV before treatment could independently predict OS survival. SUVmaxpet2, SUVmaxpet3, and SUVmaxpet4 could predict RFS. Patients with reductions of SUVmaxpet4 less than 75% had a poor PFS, RFS, and OS.

Pre-treatment metabolic tumor volume and total lesion glycolysis are useful prognostic factors for esophageal squamous cell cancer patients.

OBJECTIVES: To study application of the maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) with 18F-FDG PET/CT for predicting prognosis of esophageal squamous cell cancer (ESC) patients. METHODS: Eighty-six patients with ESC staged from I to IV were prospectively enrolled. Cisplatin-based chemoradiotherapy (CCRT) or palliative chemoradiotherapy were the main treatment methods and none received surgery. 18F-FDG PET/CT scans were performed before the treatment. SUVmax, MTV, and TLG were measured for the primary esophageal lesion and regional lymph nodes. Receiver operating characteristic curves (ROCs) were generated to calculate the P value of the predictive ability and the optimal threshold. RESULTS: MTV and TLG proved to be good indexes in the prediction of outcome for the ESC patients. An MTV value of 15.6 ml and a TLG value of 183.5 were optimal threshold to predict the overall survival (OS). The areas under the curve (AUC) for MTV and TLG were 0.74 and 0.70, respectively. Kaplan-Meier analysis showed an MTV less than 15.6 ml and a TLG less than 183.5 to indicate good media survival time (p value <0.05). In the stage III-IV patient group, MTV could better predict the OS (P < 0.001), with a sensitivity and specificity of 0.80 and 0.67, respectively. CONCLUSIONS: Pre-treatment MTV and TLG are useful prognostic factors in non- surgical ESC.

Infrared photodissociation spectroscopy of iron nitrosyl cation complexes: Fe(NO)n⁺ (n = 1-5).

Infrared spectra of mass-selected mononuclear iron nitrosyl cations Fe(NO)n(+) with n = 1-5 and their argon tagged complexes are measured via infrared photodissociation spectroscopy in the nitrosyl stretching frequency region in the gas phase. The structures are established by comparison of the experimental spectra with the simulated spectra derived from density functional calculations. Two IR active bands were observed for the argon-tagged Fe(NO)2(+) and Fe(NO)3(+) complexes, consistent with theoretical predictions that these complexes have bent C(2v) and nonplanar C(3v) symmetry, respectively. The Fe(NO)4(+) complex was characterized to have a completed coordination sphere with 17 electrons containing a bent one-electron NO ligand and three three-electron NO ligands. The Fe(NO)5(+) complex was determined to involve a Fe(NO)4(+) core ion that is solvated by an external NO molecule.

Molecular cloning and functional characterization of a novel cotton CBL-interacting protein kinase gene (GhCIPK6) reveals its involvement in multiple abiotic stress tolerance in transgenic plants.

Plant CIPKs were specific Ser/Thr protein kinases, which were activated through interaction with calcineurin B-like protein (CBL) containing four EF hands for Ca(2+) binding. The CBL/CIPK complexes play an important role in signal transduction in biotic and abiotic stresses, as well as developmental processes. Here a Ser/Thr protein kinase gene (defined as GhCIPK6), which was isolated from RNA-Seq profile during cotton somatic embryogenesis in our previous research was characterized. The GhCIPK6 gene contains an ORF of 1296 bp that putatively encodes a polypeptide of 431 amino acids with a predicted molecular mass of 48.46 kDa and isoelectric point of 9.12. Sequence alignment analysis confirmed that GhCIPK6 has no intron, and it was homologous to AtCIPK6. Expression analysis of the GhCIPK6 suggested that they might function in diverse tissues, including styles and anthers but not fibers. In addition, expression of the GhCIPK6 gene was induced by salt, drought and ABA treatments. Overexpression of GhCIPK6 significantly enhances the tolerance to salt, drought and ABA stresses in transgenic Arabidopsis, indicating that GhCIPK6 acts as a positive regulator in response to salt and drought stress, and is supposed to be a potential candidate gene to improve stress tolerance by genetic manipulation in cotton and other crops.

[Serial (18)F-FDG PET-CT imaging during radiotherapy for nasopharyngeal carcinoma: a prospective clinical study].

OBJECTIVE: The primary aim of this prospective study was to use serial (18)F-FDG PET-CT imaging to evaluate the trend of the tumor's maximum standardized uptake value (SUVmax) during radiotherapy (RT) for patients with nasopharyngeal carcinoma (NPC), and to explore the possibility of early evaluation of the tumor bio-metabolic response during radiotherapy. METHODS: Sixty patients with biopsy-proven primary NPC were prospectively enrolled into the study. All patients underwent four (18)F-FDG PET-CT scans: one initial scan before RT/cisplatin based concurrent chemoradiotherapy, at the point of 50 Gy during RT, the end of RT, and one month after RT, respectively. Tumor (18)F-FDG uptake was analyzed according to the World Health Organization pathological type. RESULTS: There was a significant difference (P < 0.001) of the mean of SUVmax of the primary site among pretreatment (11.20 ± 5.37) and posttreatment at the dose of 50 Gy (3.50 ± 1.59), at the end of RT (3.05 ± 1.56) and one month after RT (2.52 ± 1.46). There was also a significant difference (P < 0.001) of the mean of SUVmax of neck node site. However, there was a significant difference of the SUVmax between histological WHO type IIb and type IIa in the primary site (P = 0.046) [(67 ± 19)% reduction at dose 50 Gy for type IIb vs. (55 ± 24)% for type IIa] but not in the lymph nodes. CONCLUSIONS: Early PET scan during or right after RT instead of conventional 3 months interval after RT is indicated to evaluate the tumor response and to develop individualized adaptive radiotherapy in NPC. Our next study will attempt to demonstrate the results based on long-term follow-up data.

A Rasch-based validation of the Hooper Visual Organization Test in Chinese-speaking children.

The aim of this study was to examine the validation of the Hooper Visual Organization Test (HVOT) for use in children by testing for item fit, unidimensionality, item hierarchy, reliability, and screening capacity. A modified scoring system was devised for the HVOT so that children received some credit for being able to describe the function of objects. The HVOT was administered to 630 typically developing school-aged children and 210 children with Down syndrome matched for age and education. Rasch analysis and receiver operating characteristic curve were applied. Rasch analysis of data from typically developing children showed that twelve items were candidates for deletion due to poor fit to the Rasch model, violation of normality and age-related item bias. Removing these items resulted in a shortened version with 18 items that forms a reliable and strong unidimensional, hierarchical scale. The items were well targeted to the ability level of the children tested. Area under the curve for HVOT-18 was 0.84, indicating very good ability to identify visual integration deficit in children with Down syndrome. The 18-item HVOT can be summed to produce an overall index of visual synthetic ability. Subsequent work is needed to validate its use in other childhood disabilities.