A novel fluorescent probe based on carbazole-thiophene for the recognition of hypochlorite and its applications.

A carbazole thiophene-aldehyde and 4-methylbenzenesulfonhydrazide conjugate CSH was synthesized by introducing 5-thiophene aldehyde at the 3-position of the carbazole group as the precursor and then condensing it with 4-methylbenzenesulfonhydrazide. CSH has high selectivity and sensitivity towards ClO-, which can specifically identify ClO- by UV-Vis and fluorescence spectroscopy. CSH can rapidly respond to ClO- in the physiological pH range through a fluorescence quenching pattern, accompanied by the color of CSH changing markedly from turquoise to yellowish green under the 365 nm UV light. Probe CSH exhibits a quantitative response to ClO- (0-11 µM) with a low detection limit (1.16 × 10-6 M). Cell imaging experiments have shown that CSH can capture fluorescent signals in the cyan and yellow channels of HeLa cells through fluorescence confocal microscopy, and can successfully identify exogenous ClO- in HeLa cells. In addition, probe CSH can also be used to detect ClO- in environmental water samples. These results indicate that CSH has potential application prospects in the environmental analysis and biological aspects.

Electroacupuncture at ST36 acupoint regulates stem cells during experimental autoimmune encephalomyelitis.

BACKGROUND: Electroacupuncture (EA) is given to assist in the treatment of MS, which is an effective therapeutic method. However, the therapy mechanism of EA related to stem cells in the treatment of MS is not yet known. In this study, we used a classic animal model of multiple sclerosis: experimental autoimmune encephalomyelitis (EAE) to evaluate the therapeutic effect of EA at Zusanli (ST36) acupoint in EAE and shed light on its potential roles in the effects of stem cells in vivo. METHODS: The EAE animal models were established. From the first day after immunization, EAE model mice received EA at ST36 acupoint, named the EA group. The weight and clinical score of the three groups were recorded for 28 days. The demyelination, inflammatory cell infiltration, and markers of neural stem cells (NSCs), hematopoietic stem cells (HSCs), and mesenchymal stem cells (MSCs) were compared. RESULTS: We showed that EAE mice treated with EA at ST36 acupoint, were suppressed in demyelination and inflammatory cell infiltration, and thus decreased clinical score and weight loss and mitigated the development of EAE when compared with the EAE group. Moreover, our data revealed that the proportions of NSCs, HSCs, and MSCs increased in the EA group compared with the EAE group. CONCLUSIONS: Our study suggested that EA at ST36 acupoint was an effective nonpharmacological therapeutic protocol that not only reduced the CNS demyelination and inflammatory cell infiltration in EAE disease but also increased the proportions of various stem cells. Further study is necessary to better understand how EA at the ST36 acupoint affects EAE.

The research on CO oxidation over Ce-Mn oxides: The preparation method effects and oxidation mechanism.

A series of CeO2-MnOx for highly efficient catalytical oxidation of carbon monoxide were prepared by citrate sol-gel (C), hydrothermal (H) and hydrothermal-citrate complexation (CH) methods. The outcome indicates that the catalyst generated using the CH technique (CH-1:8) demonstrated the greatest catalytic performance for CO oxidation with a T50 of 98 °C, and also good stability in 1400 min. Compared to the catalysts prepared by C and H method, CH-1:8 has the highest specific surface of 156.1 m2 g-1, and the better reducibility of CH-1:8 was also observed in CO-TPR. It is also observed the high ratio of adsorbed oxygen/lattice oxygen (1.5) in the XPS result. Moreover, characterizations by the TOF-SIMS method indicated that obtained catalyst CH-Ce/Mn = 1:8 had stronger interactions between Ce and Mn oxides, and the redox cycle of Mn3++Ce4+ ↔ Mn4++Ce3+ was a key process for CO adsorption and oxidation process. According to in-situ FTIR, the possible reaction pathway for CO was deduced in three ways. CO directly oxidize with O2 to CO2, CO adsorbed on Mn4+ and Ce3+ reacts with O to form intermediates (COO-) (T > 50 °C) and carbonates (T > 90 °C), which are further oxidized into CO2.

Adhesion and proliferation of bone marrow stromal cells on acellular spinal cord scaffolds.

OBJECTIVES: This study aimed to produce an acellular spinal cord scaffold-bone marrow stromal cell (ASCS-BMSC) complex in which the growth of BMSCs transplanted into the spinal cord of rats could be simulated in vitro, facilitating the observation and evaluation of the growth of BMSCs on the ASCS for the first time. METHODS: Freeze-thaw, chemical extraction and mechanical shaking approaches were used to remove the cellular components and prepare a rat ASCS containing only the extracellular matrix (ECM) structure from the rat spinal cord. BMSCs were embedded into ASCSs and freeze-dried agarose scaffolds (FASs), and cell migration and proliferation were observed via fluorescence microscopy and the MTT assay. RESULTS: Compared with the normal rat spinal cord, the ASCS had no cell structure and retained ECM components such as type IV collagen, fibronectin and laminin, showing a three-dimensional network structure with good voids. The growth and proliferation of BMSCs on the ASCS was good, as shown by the MTT assay. Scanning electron microscopy showed that BMSCs covered 65% of the ASCS surface, and the mitochondria of BMSCs were developed and adhered to collagen fibres, as demonstrated by transmission electron microscopy. HE staining showed that BMSCs could grow inside the ASCS, and immunohistochemical staining showed that BMSCs still expressed CD44 and CD90 on the ASCS and had stem cell characteristics. CONCLUSIONS: The results of the experiment indicate that the ASCS has the ability to improve cell adhesion and proliferation. Thus, the ASCS-BMSC combination may be used to treat spinal cord injury.

Catalytic ozonation of toluene over amorphous Cu-Mn bimetallic oxide: Influencing factors, degradation mechanism and pathways.

Herein, amorphous catalysts were employed to investigate the catalytic ozonation system, revealing the degradation mechanism and influencing factors (O3 concentration, temperature, and humidity) for toluene catalytic ozonation. Cu0.2MnOx exhibited the highest toluene oxidized and excellent stability (∼85% at 60 h) based on the suitable value of Oads/Olat and potent synergy between Cu with Mn. To explore the effect of factors, the change of fresh and post-reaction samples was compared as revealed in the relevant characterization results (SEM, XRD, BET, XPS, TGA), DRIFTS and GC-MS identified the intermediates and byproducts. The results show that appropriate temperature (100 °C) and O3 concentration (2100 ppm) can effectively enhance the number of reactive oxygen species. Although H2O can increase the production of ·OH to promote degradation, it is easier to quench the active sites on the surface of amorphous catalysts. During the reaction, the main role of Cu in Cu-Mn bimetallic oxides is adsorption of toluene and O3, formation of benzoic acid, and oxidation of short-chain products. As for the adjacent Mn, it works on the cleavage of O-O in O3 and the ring-opening of benzene. Then, the mainly catalytic ozonation pathway of toluene was proposed and followed the order: toluene, benzoic acid, benzene, maleic anhydride, short-chain carbon species, CO2, and H2O.

Heterogeneous epidemic modelling within an enclosed space and corresponding Bayesian estimation.

Since March 11th, 2020, COVID-19 has been a global pandemic for more than one years due to a long and infectious incubation period. This paper establishes a heterogeneous epidemic model that divides the incubation period into infectious and non-infectious and employs the Bayesian framework to model the 'Diamond Princess' enclosed space incident. The heterogeneity includes two different identities, two transmission methods, two different-size rooms, and six transmission stages. This model is also applicable to similar mixed structures, including closed schools, hospitals, and communities. As the COVID-19 pandemic continues, our mathematical modeling can provide management insights to the governments and policymakers on how the COVID-19 disease has spread and what prevention strategies still need to be taken.

Establishment of the glioma polyploid giant cancer cell model by a modified PHA-DMSO-PEG fusion method following dual drug-fluorescence screening in vitro.

BACKGROUND: In glioma, cell fusion and the number of the polyploid giant cancer cells (PGCC) were found to be augmented with tumor grades (WHO Ⅰ-Ⅳ) and closely related to poor prognosis. However, the pathological and molecular characteristics of glioma PGCCs remain unclear due to the lack of cell model in vitro and in vivo. NEW METHOD: Here, we reported a novel approach to obtain the glioma PGCCs by the PHA-DMSO-PEG fusion method following dual drug-fluorescence screening in vitro. Glioma cells were labelled by lentiviruses infection and fusion hybrids were obtained by puromycin screening and fluorescence-activated cell sorting (FACS). RESULTS: Glioma tumor-tumor cell fusion efficiency was significantly improved by PHA and DMSO. Glioma PGCCs were successfully obtained after puromycin screening and FACS. Cell size, DNA content and chromosome numbers of the glioma PGCCs were almost twice than that of the parental glioma cells. Moreover, glioma PGCCs showed a decreased proliferation rate but enhanced temozolomide resistance potential compared to the parental cells. COMPARISON WITH EXISTING METHODS: We firstly obtained the glioma PGCCs by a modified fusion method in vitro. The fusion efficiency of the PHA-DMSO-PEG fusion method was much higher compared to PEG fusion method. Moreover, the dual drug-fluorescence screening method was more convenient and effective compared to the single one. CONCLUSIONS: We successfully established the glioma PGCC model through a modified PHA-DMSO-PEG fusion method following dual drug-fluorescence screening in vitro. Glioma PGCCs showed a deceased proliferation rate but increased TMZ resistance capacity.

Involvement of microRNA-155 in the mechanism of electroacupuncture treatment effects on experimental autoimmune encephalomyelitis.

Multiple sclerosis (MS) is a neurodegenerative and demyelinating autoimmune disease mediated by autoreactive T cells that affects the central nervous system (CNS). Electroacupuncture (EA) has emerged as an alternative or supplemental treatment for MS, but the mechanism by which EA may alleviate MS symptoms is unresolved. Here, we examined the effects of EA at the Zusanli (ST36) acupoint on mice with experimental autoimmune encephalomyelitis (EAE), the predominant animal model of MS. The effects of EA on EAE emergence, inflammatory cell levels, proinflammatory cytokines, and spinal cord pathology were examined. EA treatment attenuated the EAE clinical score and associated spinal cord demyelination, while reducing the presence of proinflammatory cytokines in mononuclear cells (MNCs), downregulating microRNA (miR)-155, and upregulating the opioid peptide precursor proopiomelanocortin (POMC) in the CNS. Experiments in which cultured neurons were transfected with a miR-155 mimic or a miR-155 inhibitor further showed that the direct modulation of miR-155 levels could regulate POMC levels in neurons. In conclusion, the alleviation of EAE by EA is characterized by reduced proportions of Th1/Th17 cells and increased proportions of Th2 cells, POMC upregulation, and miR-155 downregulation, while miR-155 itself can suppress POMC expression. These results, support the hypothesis that the effects of EA on EAE may involve the downregulation of miR-155.

The enhanced efficacy of herpes simplex virus by lentivirus mediated VP22 and cytosine deaminase gene therapy against glioma.

Despite the comprehensive treatment of surgery following by concurrent radiochemotherapy, the prognosis of malignant glioma remains unsatisfactory with an awful median survival time of only 12-18 months. This might be improved by the development of oncolytic herpes simplex virus. However, the biggest challenge of recombinant herpes simplex virus (rHSV) lies in their limited therapeutic efficiency in clinical trials. This study aims to enhance the efficacy of rHSV against glioma by a HSV-1 tegument protein VP22 modified cytosine deaminase/5-flurocytosine (CD/5-FC) suicide gene system. Stable glioma cell lines carrying CD or VP22-CD fusion gene were successfully obtained by lentiviral infection following Fluorescence-activated cell sorting. The lethal effect of the prodrug 5-FC was significantly increased in the transduced VP22-CD glioma cells compared to the transduced CD glioma cells. Interestingly, VP22 was found to elicit the enhanced efficacy of rHSV-1 against glioma. Furthermore, we detected a synergistic efficacy of rHSV-1 combined with lentivirus mediated VP22 and CD suicide gene therapy in the orthotopic glioma xenograft models. In conclusion, we successfully established the stable cell lines carrying VP22-CD fusion genes. The incorporation of VP22 further induced an enhanced efficacy of rHSV-1 as well as CD suicide gene therapy respectively and synthetically in vitro. Also, we demonstrated an increased therapeutic benefit of rHAV-1 by VP22 modified CD gene therapy against glioma in vivo.

Tunable Two-Layer Dual-Band Metamaterial with Negative Modulus.

A tunable dual-band acoustic metamaterial (AM) with nested two-layer split hollow spheres (TLSHSs) is presented here, which was achieved by adjusting the hole diameter and the ratio of the two layers' volumes. This work comprises theoretical and numerical studies. Based on sound-force analogy (SFA), TLSHSs can be considered equivalent to a model of two spring oscillators in series. The equations of two resonant frequencies were derived, which precisely provided the relation between two resonant frequencies and the hole diameter as well as the ratio of the two layers' volumes. The analytical formulas and simulation results by the finite element method (FEM) showed that there were two resonant frequencies for the TLSHSs, and their dynamic modulus became negative near the resonant frequencies. As the the diameter of two holes increased, both of the resonant frequencies underwent a blue shift. As the relative volume ratio increased, both of the resonant frequencies underwent a red shift. The calculation and simulation results were in good agreement. This kind of precisely controllable dual-band AM with negative modulus can easily be coupled to other structures with negative mass density, thereby achieving a double-negative AM in an expected frequency range.

UiO-66-NH2/GO Composite: Synthesis, Characterization and CO2 Adsorption Performance.

In this work, a new composite materials of graphene oxide (GO)-incorporated metal-organic framework (MOF)(UiO-66-NH2/GO) were in-situ synthesized, and were found to exhibit enhanced high performances for CO2 capture. X-ray diffraction (XRD), scanning electron microscope (SEM), N2 physical adsorption, and thermogravimetric analysis (TGA) were applied to investigate the crystalline structure, pore structure, thermal stability, and the exterior morphology of the composite. We aimed to investigate the influence of the introduction of GO on the stability of the crystal skeleton and pore structure. Water, acid, and alkali resistances were tested for physical and chemical properties of the new composites. CO2 adsorption isotherms of UiO-66, UiO-66-NH2, UiO-66/GO, and UiO-66-NH2/GO were measured at 273 K, 298 K, and 318 K. The composite UiO-66-NH2/GO exhibited better optimized CO2 uptake of 6.41 mmol/g at 273 K, which was 5.1% higher than that of UiO-66/GO (6.10 mmol/g). CO2 adsorption heat and CO2/N2 selectivity were then calculated to further evaluate the CO2 adsorption performance. The results indicated that UiO-66-NH2/GO composites have a potential application in CO2 capture technologies to alleviate the increase in temperature of the earth's atmosphere.