Carbapenemase-Producing \u3cem\u3ePseudomonas aeruginosa \u3c/em\u3e – an Emerging Challenge

Carbapenem-resistant Pseudomonas aeruginosa (CR-PA) is a major healthcare-associated pathogen worldwide. In the United States, 10–30% of P. aeruginosa isolates are carbapenem-resistant, while globally the percentage varies considerably. A subset of carbapenem-resistant P. aeruginosa isolates harbour carbapenemases, although due in part to limited screening for these enzymes in clinical laboratories, the actual percentage is unknown. Carbapenemase-mediated carbapenem resistance in P. aeruginosa is a significant concern as it greatly limits the choice of anti-infective strategies, although detecting carbapenemase-producing P. aeruginosa in the clinical laboratory can be challenging. Such organisms also have been associated with nosocomial spread requiring infection prevention interventions. The carbapenemases present in P. aeruginosa vary widely by region but include the Class A beta-lactamases, KPC and GES; metallo-beta-lactamases IMP, NDM, SPM, and VIM; and the Class D, OXA-48 enzymes. Rapid confirmation and differentiation among the various classes of carbapenemases is key to the initiation of early effective therapy. This may be accomplished using either molecular genotypic methods or phenotypic methods, although both have their limitations. Prompt evidence that rules out carbapenemases guides clinicians to more optimal therapeutic selections based on local phenotypic profiling of non-carbapenemase-producing, carbapenem-resistant P. aeruginosa. This article will review the testing strategies available for optimizing therapy of P. aeruginosa infections

Progresso da fusariose em espigas de triticale.

Editores técnicos: Joseani Mesquita Antunes, Ana Lídia Variani Bonato, Márcia Barrocas Moreira Pimentel

Plasma extravasation mediated by lipopolysaccharide-induction of kinin B1 receptors in rat tissues.

The present study was performed to: (a) evaluate the effects of kinin B1 (Sar[D-Phe8]-des-Arg9-BK; 10 nmol/kg) and B2 (bradykinin (BK); 10 nmol/kg) receptor agonists on plasma extravasation in selected rat tissues; (b) determine the contribution of a lipopolysaccharide (LPS) (100 microg/kg) to the effects triggered by B1 and B2 agonists; and (c) characterize the selectivity of B1 ([Leu8]desArg9-BK; 10 nmol/kg) and B2 (HOE 140; 10 nmol/kg) antagonists as inhibitors of this kinin-induced phenomenon. B1 and B2 agonists were shown to increase plasma extravasation in the duodenum, ileum and also in the urinary bladder of the rat. LPS pretreatment enhanced the plasma extravasation mediated only by the B1 agonist in the duodenum, ileum, trachea, main and segmentar bronchi. These effects were prevented by the B1. but not the B2 antagonist. In normal rats, the B2 antagonist inhibited the effect of B2 agonist in all the tissues analyzed. However, in LPS-treated rats, the B2 antagonist was ineffective in the urinary bladder. These results indicate that kinins induce plasma extravasation in selected rat tissues through activation of B1 and B2 receptors, and that LPS selectively enhances the kinin effect on the B1 receptor in the duodenum, ileum, trachea and main and segmentar bronchi, and may increase B1 receptor expression in these tissues

High residual platelet reactivity during aspirin therapy in patients with non-st segment elevation acute coronary syndrome: Comparison between initial and late phases

Background: High platelet reactivity (HPR) during therapy with acetylsalicylic acid (ASA) is a poor prognostic factor in acute coronary syndromes (ACS). The prevalence of HPR during ACS is greater than that reported in stable diseases. However, it is unclear whether this prevalence of HPR is a transient phenomenon or a characteristic of this high-risk population. Objective; The main objective is to compare the effects of ASA on platelet function in the initial and late phases of ACS in a single population. Secondary objectives are: correlation between the tests between themselves and the relationship between the tests and the variation of the inflammatory markers (C-reactive protein and interleukin-6). Methods: Seventy patients with non-ST segment elevation (NSTE) ACS in use of 100-200 mg of ASA per day for at least 7 days were prospectively studied. Platelet function was assessed in the first 48 hours and subsequently after 3 months using four methods: VerifyNow (TM) (VFN), whole blood platelet aggregation (WBPA) with arachidonic acid (AA) and collagen as agonists, and platelet function analyzer (PFA). The level of statistical significance considered was < 0.05. Results: According to the more specific methods (WBPA with AA and VFN), the incidence of HPR was significantly higher in the early phase than in the late phase: WBPA with AA: 31% versus 13%, p = 0.015; VFN: 32% versus 16%, p = 0.049. The other methods tested, which were less specific for ASA, did not show significant differences between phases. The correlation between the methods was weak or moderate (r ranging from 0.3 to 0.5, p < 0.05), and there were no significant associations between HPR and inflammatory markers. Conclusion: The prevalence of HPR during AAS therapy, assessed by specific methods for cyclooxygenase 1 (COX-1), is higher during the acute phase than in the late phase of NSTE ACS

Directed Carbapenemase Testing Is No Longer Just for Enterobacterales: Cost, Labor, and Workflow Assessment of Expanding Carbapenemase Testing to Carbapenem-Resistant \u3cem\u3eP. aeruginosa\u3c/em\u3e

Molecular carbapenem-resistance testing, such as for the presence of carbapenemases genes, is commonly implemented for the detection of carbapenemase-producing Enterobacterales. Carbapenemase-producing P. aeruginosa is also associated with significant morbidity and mortality, although; prevalence may be underappreciated in the United States due to a lack of carbapenemase testing. The present study sought to compare hands-on time, cost and workflow implementation of carbapenemase gene testing in Enterobacterales and P. aeruginosa isolates versus sending out isolates to a public health laboratory (PHL) for testing to assess if in-house can provide actionable results. The time to carbapenemase gene results were compared. Differences in cost for infection prevention measures were extrapolated from the time of positive carbapenemase gene detection in-house versus PHL. The median time to perform carbapenemase gene testing was 7.5 min (range 5–14) versus 10 min (range 8–22) for preparation to send isolates to the PHL. In-house testing produced same day results compared with a median of 6 days (range 3–14) to receive results from PHL. Cost of in-house testing and send outs were similar ($46.92 versus$40.53, respectively). If contact precautions for patients are implemented until carbapenemase genes are ruled out, in-house testing can save an estimated $76,836.60 annually. Extension of in-house carbapenemase testing to include P. aeruginosa provides actionable results 3–14 days earlier than PHL Standard Pathway testing, facilitating guided therapeutic decisions and infection prevention measures. Supplemental phenotypic algorithms can be implemented to curb the cost of P. aeruginosa carbapenemases testing by identifying isolates most likely to harbour carbapenemases

Development of an image analysis procedure for identifying protozoa and metazoa typical of activated sludge system

A procedure for the semi-automatic identification of the main protozoa and metazoa species present in the activated sludge of wastewater treatment plants was developed. This procedure was based on both image processing and multivariable statistical methodologies, leading to the use of the image analysis morphological descriptors by discriminant analysis and neural network techniques. The image analysis programwritten in Matlab has proved to be adequate in terms of protozoa and metazoa recognition, as well as for the operating conditions assessment.National Council of Scientific and Technological Development of Brazil (CNPq); BIEURAM III ALFA co-operation project (European Commission); Fundação para a Ciência e a Tecnologia (FCT

Stalked protozoa identification by image analysis and multivariable statistical techniques

Protozoa are considered good indicators of the treatment quality in activated sludge systems as they are sensitive to physical, chemical and operational processes. Therefore, it is possible to correlate the predominance of certain species or groups and several operational parameters of the plant. This work presents a semi-automatic image analysis procedure for the recognition of the stalked protozoa species most frequently found in WWTP by determining the physical, morphological and signature data and subsequent processing by discriminant analysis and neural network techniques. Physical descriptors were found to be responsible the largest identification ability and the crucial Opercularia and V. microstoma micro-organisms identification provided some degree of confidence to establish their presence in WWTP

Recognition of protozoa and metazoa using image analysis tools, discriminant analysis, neural networks and decision trees

Protozoa and metazoa are considered good indicators of the treatment quality in activated sludge systems due to the fact that these organisms are fairly sensitive to physical, chemical and operational processes. Therefore, it is possible to establish close relationships between the predominance of certain species or groups of species and several operational parameters of the plant, such as the biotic indices, namely the Sludge Biotic Index (SBI). This procedure requires the identification, classification and enumeration of the different species, which is usually achieved manually implying both time and expertise availability. Digital image analysis combined with multivariate statistical techniques has proved to be a useful tool to classify and quantify organisms in an automatic and not subjective way. Thiswork presents a semi-automatic image analysis procedure for protozoa and metazoa recognition developed in Matlab language. The obtained morphological descriptors were analyzed using discriminant analysis, neural network and decision trees multivariable statistical techniques to identify and classify each protozoan or metazoan. The obtained procedure was quite adequate for distinguishing between the non-sessile protozoa classes and also for the metazoa classes, with high values for the overall species recognition with the exception of sessile protozoa. In terms of the wastewater conditions assessment the obtained results were found to be suitable for the prediction of these conditions. Finally, the discriminant analysis and neural networks results were found to be quite similar whereas the decision trees technique was less appropriate.National Council of Scientific and Technological Development of Brazil (CNPq); BI-EURAM III ALFA co-operation project (European Commission); Fundação para a Ciência e a Tecnologia (FCT)