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Due to its ability to reversibly bind O2, alongside a relatively low redox reactivity and a limited cytotoxicity, the oxygen-carrying protein hemerythrin has been considered as an alternative to hemoglobin in preparing blood substitutes. In order to increase the hydrodynamic volume and lower antigenicity, two site-directed variants, H82C and K92C, were engineered that contained a single cysteine residue on the surface of each hemerythrin octamer for the specific attachment of polyethylene glycol (PEG). A sulfhydryl-reactive PEGylation reagent with a 51.9 Å spacer arm was used for selective cysteine derivatization. The mutants were characterized by UV-vis spectroscopy, size-exclusion chromatography, oxygen affinity, and autooxidation rate measurements. The H82C variant showed altered oligomeric behavior compared to the wild-type and was unstable in the met form. The PEGylated K92C variant is reasonably stable, displays an oxygen affinity similar to that of the wild-type, and shows an increased rate of autoxidation; the latter disadvantage may be counteracted by further chemical modifications. [ABSTRACT FROM AUTHOR]

A mud volcano (MV) is a naturally hydrocarbon-spiked environment, as indicated by the presence of various quantities of PAHs and aromatic isotopic shifts in its sediments. Recurrent expulsion of various hydrocarbons consolidates the growth of hydrocarbonoclastic bacterial communities in the areas around MVs. In addition to the widely-known availability of biologically malleable alkanes, MVs can represent hotbeds of polyaromatic hydrocarbons (PAHs), as well - an aspect that has not been previously explored. This study measured the availability of highly recalcitrant PAHs and the isotopic signature of MV sediments both by GC-MS and δ13C analyses. Subsequently, this study highlighted both the occurrence and distribution of putative PAH-degrading bacterial OTUs using a metabarcoding technique. The putative hydrocarbonoclastic taxa incidence are the following: Enterobacteriaceae (31.5%), Methylobacteriaceae (19.9%), Bradyrhizobiaceae (16.9%), Oxalobacteraceae (10.2%), Comamonadaceae (7.6%) and Sphingomonadaceae (5.5%). Cumulatively, the results of this study indicate that MVs represent polyaromatic hydrocarbonoclastic hotbeds, as defined by both natural PAH input and high incidence of putative PAH-degrading bacterial OTUs. [ABSTRACT FROM AUTHOR]

Introduction: Neuroblastoma ranks third among pediatric malignancies.Case Report: The case of a 3-year-old child is presented, who suddenly had frequent, unproductive, emetic cough; fever; and weight loss. Lung X-ray showed an opacity situated in the posterior superior mediastinum. Thoracic ultrasound revealed a slightly inhomogeneous, hypoechoic mass located in the posterior superior mediastinum. Computed tomography evidenced a tumor mass with homogeneous appearance in the costo-vertebral groove. Histological examination confirmed the diagnosis of ganglioneuroblastoma.Conclusion: Although history and clinical examination provided few elements, diagnosis was made based on imaging and histopathological examination. [ABSTRACT FROM AUTHOR]

Celiac disease remains one of the most challenging pathologies of the small intestine. It involves multiple pathogenic pathways and there are no disease-changing pharmacological agents available against it yet. The term microbiota refers to the community of microorganisms that inhabit a particular region of the body. Normal gut microbiota has a vital role in maintaining the intestinal homeostasis and promoting health. Celiac disease is associated with microbiota alteration, especially with an increase in the number of Gram-negative bacteria and a decrease in the number of Gram-positive bacteria. There is a strong relationship between intestinal dysbiosis and celiac disease, and recent studies are aimed at determining whether the celiac disease is a risk factor for dysbiosis or dysbiosis is for celiac disease. Therefore, the aim of this review was to assess the latest findings regarding the gut microbiota and its impact on the celiac disease, including therapeutic aspects. [ABSTRACT FROM AUTHOR]

The North of Romania is known for its wooden churches dating from the seventeenth and eighteenth centuries. Their deterioration constitutes a major problem due to their value for the cultural heritage. The microbial community from a seventeenth-century wooden church (Nicula, Romania) was investigated by characterization of uncultivated and cultivated bacteria using 16S rDNA sequence analysis. The study revealed not only the prevalence of the Bacillus thuringiensis strain IAM 12077 but also the presence of new microbial communities of Planomicrobium and Variovorax that were not previously reported in paintings or on wood. The identification of fungi showed the presence of seven common genera found on the walls and icon surfaces. Common bacteria from the human oral microbiota were not identified in the bacterial community. [ABSTRACT FROM AUTHOR]

Hemerythrin is proposed as an alternative to hemoglobin-based blood substitutes. In contrast to hemoglobin, hemerythrin exhibits negligible reactivity towards oxidative and nitrosative stress agents (peroxide, nitric oxide, nitrite). Protocols for attachment of polyethylene glycol and glutaraldehyde cross-linking of Hr are described. These derivatizations appear to have favorable effects on O affinity and autoxidation rates for use in blood substitutes. Based on lessons learned from hemoglobin-based blood substitutes, these derivatizations should also help limit extravasation and antigenicity of a hemerythrin-based blood substitute. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]