Thermal Decomposition of Co-Doped Calcium Tartrate and Use of the Products for Catalytic Chemical Vapor Deposition Synthesis of Carbon Nanotubes.

Thermal decomposition of Co-doped calcium tartrate in an inert atmosphere or air was studied using thermogravimetric analysis and X-ray absorption fine structure (XAFS) spectroscopy. It was shown that the powder substance containing 4 at.% of cobalt completely decomposes within 650-730 °C, depending on the environment, and the formation of Co clusters does not proceed before 470 °C. The products of decomposition were characterized by transmission electron microscopy, XAFS, and X-ray photoelectron spectroscopy. Surfaceoxidized Co metal nanoparticles as large as ∼5.6 ( 1.2 nm were found to form in an inert atmosphere, while the annealing in air led to a wide distribution of diameters of the nanoparticles, with the largest nanoparticles (30-50 nm) mainly present as a Co3O4 phase. It was found that the former nanoparticles catalyze the growth of CNTs from alcohol while a reducing atmosphere is required for activation of the latter nanoparticles. We propose the scheme of formation of CaO-supported catalyst from Co-doped tartrate, depending on the thermal decomposition conditions

The Association Between TNP2 Gene Polymorphisms and Iranian Infertile Men with Varicocele: A Case-control Study

Background: Numerous researches have provided great evidence that revealed the relationship between varicocele and sperm DNA damage. Objective: Because of the crucial role of nuclear transition proteins (TPs) in sperm DNA condensation and integrity, this case-control study was designed to study TNP2 gene nucleotide variations in Iranian patients with varicocele. Materials and Methods: PCR-SSCP and DNA sequencing were used to search for mutations in exons 1 & 2 of the TNP2 gene in 156 infertile patients with varicocele and 150 fertile men. Results: The results of sequencing showed three variants at positions c.301C > T (p.R101C), c.391C > T (p.R131 W), and g.IVS1-26G >C (rs8043625) of TNP2 gene. It was found that varicocele risk in men who have the CC genotype of g.IVS1-26G >C SNP is higher than those who don't have these genotypes (according to Co-dominant model, Dominant model, Recessive model, and Over-dominant model). The haplotype-based analysis showed that (C/C/T) and (C/T/T) haplotypes were a risk factor of in patients with varicocele compared to controls (OR = 3.278, p = 0.000 and OR= 9.304, p = 0.038, respectively). Conclusion: Because of the significant difference in the genotype and allele frequencies of g.IVS1-26G >C SNP in the intronic region of TNP2 in patients with varicocele compared with controls and also because of the high conservation of this SNP position during evolution, this SNP may be involved in some important processes associated with the expression of this gene like mRNA splicing, but the exact mechanism is not clear

Metronidazole conjugated bismuth sulfide nanoparticles for enhanced X-ray radiation therapy

Over the past few years, several types of radiosensitizers have been developed to address the challenges of tumor hypoxia in favor of cancer radiotherapy. In this study, we aimed to synthesize a nano-radiosensitizers via conjugation of metronidazole (Met) to bovine serum albumin coated bismuth sulfide nanoparticles (Bi2S3@BSA NPs), named Bi2S3@BSA-Met. The NPs were characterized with different techniques. Bi2S3@BSA-Met NPs were shown to have a mean hydrodynamic particle size around 154 nm and a spherical shape with homogenous size distribution. Apoptosis assay revealed that the combination of Bi2S3@BSA-Met NPs with X-Ray irradiation potentiated the cell apoptotic rate. Furthermore, one of the most striking results to emerge from the data comparison was the effects of Met on radiosensitization of 4T1 cells under hypoxia condition. Conjugation of Met to Bi2S3@BSA NPs resulted in superior cell cytotoxicity upon X-ray irradiation. Results provide unprecedented evidence for the potential capability of Met as an effective radiation sensitizer for hypoxic tumor cells.. © 202