Two-step thermotropic phase transition and dielectric relaxation in 1D supramolecular lead iodide perovskite [NH4@18-crown ether]PbI3.

The supramolecular lead iodide perovskite crystals, {[NH4(18-crown-6)]PbI3}∞ (1), (18-crown-6 = 1,4,7,10,13,16-hexaoxacyclooctadecane), was successfully achieved by a facile solvent evaporation strategy using a DMF solution containing equal molar quantities of PbI2, NH4I and 18-crown-6. The supramolecular perovskite was characterized by microanalysis for C, H and N elements, thermogravimetric (TG) analysis, differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and single crystal X-ray diffraction techniques. DSC measurements demonstrated that 1 experiences a two-step thermotropic phase transition around 333 K and 383 K, respectively. The phase transition is relevant to the disorder-order transformation of the 18-crown-6 molecule at ∼333 K, while both breaking-symmetry and ordered-disordered transformation of the 18-crown-6 molecule occurred at ∼383 K. In addition, the sharp change of the PbI6 coordination octahedron distortion degree plays a synergistic role in the two-step phase transition. The dielectric relaxation occurs above 243 K in 1 and is mainly attributed to the displacement of the NH4+ ions relative to the ring of the 18-crown-6 molecule and {PbI3}∞ chain induced by an AC electrical field.

A comparison of capillary electrophoresis and next-generation sequencing in the detection of immunoglobulin heavy chain H and light chain κ gene rearrangements in the diagnosis of classic hodgkin's lymphoma.

This study aimed to compare the application value of capillary electrophoresis and next-generation sequencing for immunoglobulin (IG) gene rearrangement in the diagnosis of classic Hodgkin's lymphoma. Twenty paraffin-embedded specimens from patients with classic Hodgkin's lymphoma were screened. For gene rearrangement detection, the ABI 3500 Genetic Analyzer and ABI Ion GeneStudio S5 Plus sequencing system were used, respectively, and the results were compared. Five cases with monoclonal rearrangements (25%, 5/20) were detected by Capillary Electrophoresis, and positivity for the FR1, FR2, FR3, and IGк loci was 5%, 10%, 10%, and 15%, respectively; 12 cases with monoclonal rearrangements (60%, 12/20) were detected by Next-generation Sequencing where the positivity of the above corresponding loci were 35%, 45%, 50%, and 30%, respectively. Among the 20 samples, 6 IGк clonal rearrangements were detected, and the usage frequency (66.7%) of IGкJ4 was the highest in the IGкJ subgroup. The usage frequency of IGкV1 and IGкV3 in the GкV sub-group was 33.3% and 33.3%, respectively. Twelve immunoglobulin heavy chain (IGH) clonal rearrangements were detected among the 20 samples, and the order of usage frequency in the IGH joining region J (IGHJ) subgroup was IGHJ4 > IGHJ5 > IGHJ6 > IGHJ3. The gene with the highest usage frequency in the IGH variable (IGHV) subgroup was IGHV3 (50%) and the percentage of IGHV mutations ranged from 0% ± 11.45% with an average frequency of 3.34%. Compared with Capillary Electrophoresis, Next-generation Sequencing showed a higher positivity in the detection of gene clonal rearrangements, was more accurate in the interpretation of results.

Enhancing immunogenicity of HPV16 E7 DNA vaccine by conjugating codon-optimized GM-CSF to HPV16 E7 DNA.

OBJECTIVE: To generate immunity against human papillomavirus (HPV), the use of a recombinant DNA vaccine to carry an appropriate target gene is a promising and cost-effective approach. Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a potent immunomodulatory cytokine that enhances the efficacy of vaccines by promoting the development and prolongation of humoral and cellular immunity. In this study, we linked codon-optimized GM-CSF (cGM-CSF) to the HPV16 E7 sequence as fused protein and evaluated the immunogenic potential of this DNA vaccine. MATERIALS AND METHODS: We have demonstrated that cGM-CSF enhanced immunity against tumor challenges by generating and promoting the proliferation of HPV16 E7-specific CD8+ T cells, which secrete IFN-γ in the murine model. In this study, we aimed to evaluate the immunogenic potential of DNA vaccine that constructed by linking codon-optimized GM-CSF to HPV16 E7 sequence in the animal model. We study the half-life of RNA decay and cellular location of HPV16 E7 by Q-PCR and Western blot. We also assess immune response in the animal model by flow cytometry and ELISA. RESULTS: The cGM-CSF-E7 sequence increased and extended the expression of E7 mRNA, in comparison with the E7 sequence alone. Mice vaccinated with the cGM-CSF-E7 DNA vaccine exhibited a slower rate of tumor growth than those vaccinated with the unconjugated E7 DNA vaccine. We also found that the CD4 and CD8+ T cells from these mice showed strong secretion of IFN-γ. CONCLUSION: Through in vivo antibody depletion experiments, we demonstrated that both CD4+ and CD8+ T cells play an important role in the suppression of tumor growth.

Polidocanol sclerotherapy for multiple gastrointestinal hemangiomas: A case report.

BACKGROUND: Gastrointestinal (GI) hemangioma has a low incidence among systemic hemangiomas, and some GI hemangiomas occur in the intestine, stomach, and esophagus. Polidocanol has been increasingly used in sclerotherapy. However, this paper reports that minimally invasive treatment of multiple hemangiomas with large diameters can achieve satisfactory results by multipoint injection. CASE SUMMARY: A 46-year-old female patient was hospitalized in another hospital for cough. We accidentally found thickening of the lower esophagus by chest computed tomography. The patient was eventually diagnosed with multiple GI hemangiomas and underwent a series of examinations including esophagogastroduodenoscopy (EGD), endoscopic ultrasound, and magnetic resonance imaging. We calculated the dose of polidocanol according to the volumes of the hemangiomas, fixed the target vein with the help of a transparent cap, and then administered polidocanol via multipoint injection into the hemangiomas under endoscopic guidance. EGD and endoscopic ultrasound showed that the hemangiomas disappeared. The color of the esophageal mucosa returned to normal 1 mo after sclerotherapy. CONCLUSION: Sclerotherapy may be a safe and effective method for treating multiple hemangiomas of the alimentary canal.

Facile synthesis of platinum-rhodium alloy nanodendrites as an advanced electrocatalyst for ethylene glycol oxidation and hydrogen evolution reactions.

Direct ethylene glycol fuel cells (DEGFCs) and water splitting devices have received intensive interest during the past few decades. However, the commonly used Pt catalysts are seriously restricted by the high cost and very low resistance to CO-like intermediates during the catalysis. Herein, a general and simple solvothermal method was developed to synthesize three-dimensional (3D) bimetallic alloyed PtRh nanodendrites (NDs) for ethylene glycol oxidation reaction (EGOR) and hydrogen evolution reaction (HER). Citric acid (CA) and cetyltrimethylammonium chloride (CTAC) played important roles in formation of such dendritic structures. The optimized Pt56Rh44 NDs displayed the greatest mass activity (MA) for EGOR in 0.5 M KOH, which was 2.6-fold higher than commercial Pt black, coupled with the remarkable increase in the HER activity with a decayed overpotential of 20.0 mV to drive a current density of 10 mA cm-2 relative to the homemade Pt41Rh59 NDs (26.2 mV), Pt81Rh19 NDs (26.2 mV), Pt black (44.3 mV), Pt/C (44.4 mV) and Rh NFs (37.3 mV). This work offers some constructive guidelines for synthesis of advanced Pt-based catalysts in such energy devices.

[Downregulation of 53BP1 by short hairpin RNA enhances radiosensitivity in laryngeal carcinoma cells].

OBJECTIVE: To determine the effect of downregulation of 53BP1 expression on cell growth and radiosensitivity in laryngeal carcinoma Hep-2 cells. METHODS: HEP-2 cell lines were established with a stable knockdown of 53BP1 with short hairpin RNA (shRNA). The level of expressed protein of negative control group (NC),wild type Hep-2 and downregulation of 53BP1 (P6) group was determined by Western blotting. Proliferation on normal conditions was detected by MTT. Radiosensitivity and growth of cells were detected by flow cytometry. RESULTS: A stable 53BP1 downregulated cell line P6 was established. Similar cell growth was observed between the 53BP1 downregulated cells and the control cells. The downregulation of 53BP1 reduced the number of clonogenic cells exposed to radiation. Compared with wild type Hep-2 group and NC group, Western blot results showed a decrease in 53BP1 protein level in P6 group (P < 0.05), reducing the ratio of arrest of G2/M with radiation dose increased (P < 0.05). MTT results revealed the lower 53BP1 protein level did not affect the cell proliferation. After exposure to 0, 2, 6, 10 Gy ionizing radiation (IR), P6 cells had lower, radiosensitivity parameters (D0, SF2, Dq, N) than controls and wild type Hep-2 (P < 0.05). CONCLUSION: RNA interference could effectively down-regulate the expression of 53BP1 and reduce arrest of G2/M phase, thus enhancing the radiosensitivity of Hep-2 cell line.