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Metagenomics has emerged as a central technique for studying the structure and function of microbial communities. Often the functional analysis is restricted to classification into broad functional categories. However, important phenotypic differences, such as resistance to antibiotics, are often the result of just one or a few point mutations in otherwise identical sequences. Bioinformatic methods for metagenomic analysis have generally been poor at accounting for this fact, resulting in a somewhat limited picture of important aspects of microbial communities. Here, we address this problem by providing a software tool called Mumame, which can distinguish between wildtype and mutated sequences in shotgun metagenomic data and quantify their relative abundances. We demonstrate the utility of the tool by quantifying antibiotic resistance mutations in several publicly available metagenomic data sets. We also identified that sequencing depth is a key factor to detect rare mutations. Therefore, much larger numbers of sequences may be required for reliable detection of mutations than for most other applications of shotgun metagenomics. Mumame is freely available from http://microbiology.se/software/mumame

Titanium alloys have created a biomedical revolution in the past three decades and several research works are being carried out globally to combat the day to day challenges posed by the biomedical industries to meet the needs of a patient-friendly implant. Enhancement of corrosion and wear resistance of titanium alloys serve as the major treat for the stability of implant material after implantation. These problems could be overcome through various objectives, one among them being alloying titanium with non-toxic β-stabilizer elements to both increase the surface-related properties and improve biocompatibility. Other objectives include surface engineering methods such as coating, oxidation, nanograined surface and laser texturing. Overall, in this article an attempt has been made to bring out the current advances in the development of highly stable Ti-alloys with superior corrosion and wear resistance through various processes has been reviewed in detail.

In the present report, silver nanoparticles were synthesized using Piper nigrum extract for in vitro cytotoxicity efficacy against MCF-7 and Hep-2 cells. The silver nanoparticles (AgNPs) were formed within 20 minutes and preliminarily confirmed by UV-Visible spectroscopy. Further, it was characterized by FT-IR and HR-TEM. The UVVisible analysis showed the strong broad peak located at 441 nm observed for Ag nanoparticles. TEM images of biosynthesized AgNPs pre-dominantly spherical shape with particle size in the range 20 nm. MTT assays were carried out using various concentrations of silver nanoparticles and Piper nigrum extract ranging from 10 to 100μg/ml. At various concentrations, biosynthesized silver nanoparticles showed a significant cytotoxic effect against both MCF-7 and Hep-2 cells compared to Piper nigrum extract. Therefore, the results reveal excellent applications of green synthesis of silver nanoparticles using Piper nigrum

Background: Neopterin, a metabolite of guanosine, belongs to the class of chemical compounds known as pteridines and is an early and valuable marker of cellular immunity. Recently, it was shown to be associated with the initiation and progression of periodontal disease. The aim of the present study was to assess the relationship between clinical parameters and concentrations of neopterin within gingival crevicular fluid (GCF) from inflamed gingiva and periodontitis sites before and after the treatment of periodontitis. Methods: Sixty age (35 to 65 years)- and gender-matched (30 males and 30 females) subjects were recruited and divided into the following four groups of 15 subjects each based on gingival index, Ramfjord periodontal disease index, clinical attachment loss (CAL), and radiographic parameters (bone loss): healthy (group 1), gingivitis (group 2), mild periodontitis (group 3), and moderate to severe periodontitis (group 4). A fifth group consisted of the 15 subjects from group 4, 6 to 8 weeks after treatment (scaling and root planing). GCF was collected from each patient, and the neopterin levels were determined by enzyme immunoassay. Results were analyzed statistically. Results: The mean concentration of neopterin in GCF was the highest in group 4 (51 nmol/l) and the lowest in group 1 (1.36 nmol/l). The mean neopterin concentrations in group 2 (9.69 nmol/l) and group 3 (16.58 nmol/l) fell between the highest and lowest values. This suggested a positive correlation between CAL and GCF neopterin concentrations. Neopterin levels in group 4 decreased to 1.77 nmol/l after treatment (group 5). Conclusions: Neopterin increased in parallel with the severity of inflammatory disease. Its levels in GCF may be potentially useful as an indicator of periodontal inflammation and the host response.