Anti-VIM monoclonal antibody, clone WJ-SF/2 [APC]

Decomposition of bodies generates several types of polar volatile organic compounds (VOCs), whose types, patterns and ratios change during the various stages of decomposition and, therefore, their determination has huge potential to provide useful information to disclose events related to the time of death, or body surrounding environment. As sample preparation is a mandatory key-point in a method development, this research aims to develop a simple, accurate and rapid approach to study death-related polar VOCs based on headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography-time of flight mass spectrometry (GC x GC-ToFMS) analysis. The performance of zwitterionic PIL-based fibers (containing a [VIm(+)C(9)COO(-)] monomer and a [(VIm)(2)Cl-2(2)+]-2Br(-) crosslinker), tailored for polar compounds, was evaluated for a set of 19 analytes associated with the unique odour created by decomposing bodies, and it was compared to the commercially-available fibers: divinylbenzene/carboxen/poly(dimethylsiloxane) - DVB/CAR/PDMS, poly(dimethylsiloxane)/divinylbenzene - PDMS/DVB and polyacrylate (PA). Fibers with absorptive-type mechanism, such as PA and PIL, showed the best results in the balance of the parameters studied, being able to detect analytes at ng level and providing a profile representative of the headspace composition, thus they may represent a useful tool to respond to current challenges in forensic taphonomy. The reproducibility (with relative standard deviation lower than 18%, depending on the analyte) and relative recoveries (higher than 99.1%) were similar and acceptable for both fibers. The zwitterionic PIL, with ca. 4 times smaller film thickness than PA, still has potential to have the best performance, supported by the efforts to obtain thicker sorbent coatings.

Resistance to antibiotics is one of the most relevant public health concerns in the world. Aquatic environments play an important role because they are reservoirs for antibiotic resistance genes and antibiotic-resistant strains, contributing to the spread of resistance. The present study investigated the resistome in Lake Bolonha (three sampling sites) in the Amazon region using a metagenomics approach and culture-dependent methods. Whole-metagenome-based results showed that the most abundant phyla were Protobacteria, Actinobacteria, Firmicutes, Bacteroidetes and Cyanobacteria. The composition of the resistome demonstrated that the genes that confer resistance to beta-lactams were prevalent at all sampling sites, followed by genes conferring resistance to aminoglycosides and tetracycline. Acquired genes encoding extended-spectrum beta-lactamases (e.g., bla(CTX-M)) and resistance to carbapenems (e.g., bla(IMP) and bla(VIM)) were detected through metagenome analysis. Bacteria were isolated from culture medium supplemented with cefotaxime or imipenem, and isolates were identified and analyzed for their antibiotic susceptibility profiles and resistance genes. In total, 98 bacterial isolates belonging to the genera Pseudomonas (37), Acinetobacter (32), Klebsiella (13), Enterobacter (9), Pantoe (3), Stenotrophomonas (3), and Methylobacterium (1) were obtained. Among isolates, the most abundant genes were bla(CTX-M) (28.3%), bla(SHV) (22.6%) and bla(TEM) (18.8%) in isolates from cefotaxime-supplemented medium and bla(VIM) (28.8%) and bla(IMP) (22.2%) in isolates recovered from imipenem-supplemented medium. The genes intl1 and intl2 were detected in 19.3% and 7.1% of isolates. Antibiograms showed that 94.9% (from cefotaxime-supplemented medium) and 85.7% (from imipenem-supplemented medium) of the isolates were multidrug resistant. Besides cefotaxime and imipenem, isolates were mostly resistant to aztreonam (91.8%), amoxicillin (98.8%), ampicillin (82.6%), and nalidixic acid (77.5%). Hence, the present study demonstrates that Lake Bolonha is a reservoir of bacteria resistant to antibiotics and resistance genes, some of which are of critical importance to human health.