Exploration of Zero-Valent Iron Stabilized Calcium–Silicate–Alginate Beads’ Catalytic Activity and Stability for Perchlorate Degradation

Perchlorate contamination in groundwater poses a serious threat to human health, owing to its interference with thyroid function. The high solubility and poor adsorption of perchlorate ions make perchlorate degradation a necessary technology in groundwater contaminant removal. Here, we demonstrate the perchlorate degradation by employing nano zero-valent iron (nZVI) embedded in biocompatible silica alginate hybrid beads fabricated using calcium chloride (1 wt%) as a crosslinker. The concentration of precursors (sodium alginate, sodium silicate) for bead formation was standardized by evaluating the thermal stability of beads prepared at different sodium silicate and alginate concentrations. Thermal degradation of silica alginate hybrid samples showed a stepwise weight loss during the thermal sweep, indicating different types of reactions that occur during the degradation process. The formation of the silica alginate hybrid structure was confirmed by FT-IR spectroscopy. Scanning electron microscopy (SEM) data revealed the surface morphology of silica alginate hybrid changes by varying sodium silicate and alginate concentrations. nZVI-loaded alginate–silicate polymer bead (nZVI-ASB) exhibited excellent perchlorate degradation efficiency by degrading 20 ppm of perchlorate within 4 h. Our study also showed the perchlorate degradation efficiency of nZVI-ASB is maximum at neutral pH conditions.     

Annexin A1, formyl peptide receptor,and NOX1 orchestrate epithelial repair

N-formyl peptide receptors (FPRs) are critical regulators of host defense in phagocytes and are also expressed in epithelia. FPR signaling and function have been extensively studied in phagocytes, yet their functional biology in epithelia is poorly understood. We describe a novel intestinal epithelial FPR signaling pathway that is activated by an endogenous FPR ligand, annexin A1 (ANXA1), and its cleavage product Ac2-26, which mediate activation of ROS by an epithelial NADPH oxidase, NOX1. We show that epithelial cell migration was regulated by this signaling cascade through oxidative inactivation of the regulatory phosphatases PTEN and PTP-PEST, with consequent activation of focal adhesion kinase (FAK) and paxillin. In vivo studies using intestinal epithelial specific Nox1^–/–IEC and AnxA1^–/– mice demonstrated defects in intestinal mucosal wound repair, while systemic administration of ANXA1 promoted wound recovery in a NOX1-dependent fashion. Additionally, increased ANXA1 expression was observed in the intestinal epithelium and infiltrating leukocytes in the mucosa of ulcerative colitis patients compared with normal intestinal mucosa. Our findings delineate a novel epithelial FPR1/NOX1-dependent redox signaling pathway that promotes mucosal wound repair.     

Comparison of the T2Dx instrument with T2Candida assay and automated blood culture in the detection of Candida species using seeded blood samples

As a delay in the diagnosis and treatment of candidemia is associated with increased mortality and healthcare costs, a more rapid method of detection is urgently needed. The T2Candida assay is a new rapid diagnostic test, which uses T2 magnetic resonance technology to identify Candida spp. directly from whole blood in approximately 3 hours. In this study, the performance of the BACTEC 9050 using Aerobic Plus/F blood culture bottles was compared to that of the T2Candida assay run on the T2Dx Instrument for detection of Candida albicans, Candida tropicalis, Candida parapsilosis, Candida glabrata, and Candida krusei, in seeded blood samples at concentrations between 3.1 and 11 CFU/mL. The BACTEC 9050 detected Candida growth in 100% of bottles (n = 20 replicates) within 5 days for all species (63.23 ± 30.27 hours), with the exception of Candida glabrata (0%). The T2Candida assay had a 100% detection rate for each species (n = 13–20 replicates) within 3 hours including C. glabrata. The sensitivity and specificity of the T2Candida assay were 1 and 0.978, respectively.     

Efficacy of Chloroquine for the Treatment of Uncomplicated Plasmodium falciparum Malaria in Honduras

Chloroquine (CQ) is officially used for the primary treatment of Plasmodium falciparum malaria in Honduras. In this study, the therapeutic efficacy of CQ for the treatment of uncomplicated P. falciparum malaria in the municipality of Puerto Lempira, Gracias a Dios, Honduras was evaluated using the Pan American Health Organization—World Health Organization protocol with a follow-up of 28 days. Sixty-eight patients from 6 months to 60 years of age microscopically diagnosed with uncomplicated P. falciparum malaria were included in the final analysis. All patients who were treated with CQ (25 mg/kg over 3 days) cleared parasitemia by day 3 and acquired no new P. falciparum infection within 28 days of follow-up. All the parasite samples sequenced for CQ resistance mutations (pfcrt) showed only the CQ-sensitive genotype (CVMNK). This finding shows that CQ remains highly efficacious for the treatment of uncomplicated P. falciparum malaria in Gracias a Dios, Honduras.     

2-甲酰(乙酰)取代喹啉缩氨基硫脲的合成

缩氨基硫脲类化合物有抗肿瘤、抗病毒和抗菌等多种药理活性。Barret等首次报道了乙二醛二缩氨基硫脲(Ⅰ)的抗疟活性。Klayman等研究了缩     

Spontaneous coronary artery dissection: management options in the stent era

Spontaneous coronary artery dissection (SCAD) is a rare cause of coronary obstruction, usually affecting women in the childbearing age. Pathogenetic mechanisms are elusive, and optimal treatment is not established. We describe a case of spontaneous coronary artery dissection that was successfully treated by coronary stenting. The published literature regarding the outcome of this modality of treatment in patients with SCAD is reviewed. A patient with spontaneous coronary artery dissection treated by stenting is described along with a review of the published literature regarding treatment of similar patients.     

Detection of high frequencies of HIV-1 cross-subtype reactive CD8 T lymphocytes in the peripheral blood of HIV-1-infected Kenyans

OBJECTIVES: To quantitate rapidly the frequency of HIV-1 subtype-specific and broadly HIV-1 cross-subtype-reactive CD8 T cells in the peripheral blood of HIV-1-infected individuals from a geographical region of multiple subtype endemicity. METHODS: Autologous B-lymphoblastoid cell lines infected with recombinant vaccinia-viruses expressing gag, env and nef gene products from HIV-1 subtypes A-H were used as antigen-presenting cells to stimulate CD8 T cells from cryopreserved peripheral blood mononuclear cells. Cross-subtype and subtype-specific CD8 cell responses were assessed by flow cytometry for the upregulation of IFN-gamma gene expression in specifically activated CD8 T cells. RESULTS: Strikingly high frequencies of circulating CD8 T cells (up to 11.3% of peripheral CD8 T cells) with specificity for HIV-1 were detectable using this methodology. Both subtype-specific and broadly cross-subtype-reactive CD8 T cells were detected as assessed by IFN-gamma production after stimulation. The pattern of cross-subtype reactivity appeared to be random when the results were assessed as a population, but analysis of the full-length sequence of the infecting virus for each individual showed some skewing of the CD8 cell response towards the infecting subtype. CONCLUSION: High frequencies of HIV-1 cross-subtype-reactive peripheral CD8 T cells can be detected in individuals from a multiple subtype endemic region, providing an incentive for vaccine advancement in such locations. The future assessment of the subtype specificity of cellular immune responses requires full-length sequencing of the infecting virus in conjunction with a comprehensive analysis of phenotypic and functional parameters.