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Urban wastewater treatment plants (UWTPs) are reservoirs of antibiotic resistance. Wastewater treatment changes the bacterial community and inevitably impacts the fate of antibiotic resistant bacteria and antibiotic resistance genes (ARGs). Some bacterial groups are major carriers of ARGs and hence, their elimination during wastewater treatment may contribute to increasing resistance removal efficiency. This study, conducted at a full-scale UWTP, evaluated variations in the bacterial community and ARGs loads and explored possible associations among them. With that aim, the bacterial community composition (16S rRNA gene Illumina sequencing) and ARGs abundance (real-time PCR) were characterized in samples of raw wastewater (RWW), secondary effluent (sTWW), after UV disinfection (tTWW), and after a period of 3 days storage to monitoring possible bacterial regrowth (tTWW-RE). Culturable enterobacteria were also enumerated. Secondary treatment was associated with the most dramatic bacterial community variations and coincided with reductions of ~2 log-units in the ARGs abundance. In contrast, no significant changes in the bacterial community composition and ARGs abundance were observed after UV disinfection of sTWW. Nevertheless, after UV treatment, viability losses were indicated ~2 log-units reductions of culturable enterobacteria. The analysed ARGs ( qnrS , bla CTX-M , bla OXA-A , bla TEM , bla SHV , sul1 , sul2 , and intI1 ) were strongly correlated with taxa more abundant in RWW than in the other types of water, and which associated with humans and animals, such as members of the families Campylobacteraceae , Comamonadaceae , Aeromonadaceae , Moraxellaceae, and Bacteroidaceae . Further knowledge of the dynamics of the bacterial community during wastewater treatment and its relationship with ARGs variations may contribute with information useful for wastewater treatment optimization, aiming at a more effective resistance control. [ABSTRACT FROM AUTHOR]

Mutation frequencies were studied in 174 Stenotrophomonas maltophilia isolates from clinical and nonclinical environments by detecting spontaneous rifampin-resistant mutants in otherwise-susceptible populations. The distribution of mutation frequencies followed a pattern similar to that found for other bacterial species, with a modal value of 1 x 10-8. Nevertheless, the proportion of isolates showing mutation frequencies below the modal value (hypomutators) was significantly higher for S. maltophilia than those so far reported in other organisms. Low mutation frequencies were particularly frequent among environmental S. inaltophilia strains (583%), whereas strong mutators were found only among isolates with a clinical origin. These results indicate that clinical environments might select bacterial populations with high mutation frequencies, likely by secondorder selection processes. In several of the strong-mutator isolates, functional-complementation assays with a wild-type allele of the mutS gene demonstrated that the mutator phenotype was due to the impairment of MutS activity. In silico analysis of the amino acid changes present in the MutS proteins of these hypermutator strains in comparison with the normomutator isolates suggests that the cause of the defect in MutS might be a H683P amino acid change. [ABSTRACT FROM AUTHOR]

The Crc protein is involved in the repression of several catabolic pathways for the assimilation of some sugars, nitrogenated compounds, and hydrocarbons in Pseudomonas putida and Pseudomonas aeruginosa when other preferred carbon sources are present in the culture medium (catabolic repression). Crc appears to be a component of a signal transduction pathway modulating carbon metabolism in pseudomonads, although its mode of action is unknown. To better understand the role of Crc, the proteome profile of two otherwise isogenic P. putida strains containing either a wild-type or an inactivated crc allele was compared. The results showed that Crc is involved in the catabolic repression of the hpd and hmgA genes from the homogentisate pathway, one of the central catabolic pathways for aromatic compounds that is used to assimilate intermediates derived from the oxidation of phenylalanine, tyrosine, and several aromatic hydrocarbons. This led us to analyze whether Crc also regulates the expression of the other central catabolic pathways for aromatic compounds present in P. putida. It was found that genes required to assimilate benzoate through the catechol pathway (benA and catBCA) and 4-OH-benzoate through the protocatechuate pathway (pobA and pcaHG) are also negatively modulated by Crc. However, the pathway for phenylacetate appeared to be unaffected by Crc. These results expand the influence of Crc to pathways used to assimilate several aromatic compounds, which highlights its importance as a master regulator of carbon metabolism in P. putida. [ABSTRACT FROM AUTHOR]

The aim of this study was to identify and analyze the incidence rate of amputations and their risk factors in people with Diabetes Mellitus (DM) in two specialized outpatient clinics in Brazil. This is an epidemiological, retrospective cohort study using data collected from electronic health records of 281 adult diabetic patient types 1 or 2; attended in specialized outpatient service between 2015 and 2020. Statistical analyses were performed using the 2 sample t-test or Wilcoxon-Mann-Whitney test, for quantitative variables, and the Pearson's χ2 test or Fisher's exact test for categorical variables. The investigation of the risk factors for amputation was carried out through logistic regression. The study was approved by ethical committee. The sample mean age was 65.6 years (SD 13.05), predominating male gender n = 211 (75%), type 2 DM n = 223 (86.7%), with cardiovascular disease n = 143 (63.2%), and about 68.7% (n = 156) with peripheral arterial disease (PAD). Seventy-seven had lower limb amputation (LLA), with a rate incidence of 31.9% during five years. Logistic regression analysis showed the following associations with amputation: Diabetic peripheral neuropathy increased the rate of amputation by 3.6 times (OR = 3.631, 95% CI = 1.214-11.353; P  = .022), and peripheral arterial disease increased by 10 times (OR = 10.631; 95% CI = 2.969-57.029; P  = .001). The LLA in individuals with DM in two specialized outpatient services was higher compared to international literature; DPN and PAD were confirmed as risk factors for amputation, according to literature. This finding suggests that the study population faces an increased risk of amputation, highlighting the urgent need for targeted interventions and implementing robust preventive strategies to transform the current scenario and mitigate these severe outcomes. A comprehensive approach is essential to proactively address the underlying issues and reduce the prevalence and impact of amputations in Brazil., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

This work investigates the potential utilization of Cu(i) as a reducing agent for the transformation of the platinum salt K 2 PtCl 4 , resulting in the production of stable nanoparticles. The synthesized nanoparticles exhibit a bimetallic composition, incorporating copper within their final structure. This approach offers a convenient and accessible methodology for the production of bimetallic nanostructures. The catalytic properties of these novel nanomaterials have been explored in various applications, including their use as artificial metalloenzymes and in the degradation of dyes. The findings underscore the significant potential of Cu(i)-mediated reduction in the development of functional nanomaterials with diverse catalytic applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Bimetallic nanostructures composed of gold (Au) and palladium (Pd) have garnered increased interest for their applications in heterogeneous catalysis. This study reports a simple strategy for manufacturing Au@Pd bimetallic branched nanoparticles (NPs), which offer a tunable optical response, using polyallylamine-stabilized branched AuNPs as template cores for Pd overgrowth. The palladium content can be altered by manipulating the concentration of PdCl 4 2- and ascorbic acid (AA) that are injected, which permit an overgrowth of the Pd shell up to ca. 2 nm thick. The homogeneous distribution of Pd at the surfaces of Au NPs can be carried out regardless of their size or branching degree, which allows for an adjustment of the plasmon response in the near-infrared (NIR) spectral range. As a proof of concept, the nanoenzymatic activity of pure gold and gold-palladium NPs was compared, exploring their peroxidase-like activity in the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB). The bimetallic AuPd NPs demonstrate an increase in the catalytic properties attributed to the presence of palladium at the surface of gold.

In this manuscript we briefly describe bipolar disorder (a depressive and manic mental disease), its classification, its effects on the patient, which sometimes include suicidal tendencies, and the drugs used for treatment. We also address the status quo with regard to diagnosis of bipolar disorder and recent advances in bioanalytical approaches for biomarker discovery. These approaches focus on blood samples (serum and plasma) and proteins as the main biomarker targets, and use various strategies for protein depletion. Strategies include use of commercially available kits or other homemade strategies and use of classical proteomics methods for protein identification based on "bottom-up" or "top-down" approaches, which used SELDI, ESI, or MALDI as sources for mass spectrometry, and up-to-date mass analyzers, for example Orbitrap. We also discuss some future objectives for treatment of this disorder and possible directions for the correct diagnosis of this still-unclear mental illness.