Direct Testing for KPC-Mediated Carbapenem Resistance from Blood Samples Using a T2 Magnetic Resonance Based Assay

Molecular-based carbapenem resistance testing in Gram-negative bacterial bloodstream infections (BSIs) is currently limited because of the reliance on positive blood culture (BC) samples. The T2Resistance™ panel may now allow the detection of carbapenemase- and other β-lactamase encoding genes directly from blood samples. We detected carbapenem resistance genes in 11 (84.6%) of 13 samples from patients with BC-documented BSIs (10 caused by KPC-producing Klebsiellapneumoniae and 1 caused by VIM/CMY-producing Citrobacter freundii). Two samples that tested negative for carbapenem resistance genes were from patients with BC-documented BSIs caused by KPC-producing K. pneumoniae who were receiving effective antibiotic therapy. In conclusion, our findings suggest that the T2Resistance™ panel can be a reliable tool for diagnosing carbapenem-resistant Gram-negative bacterial BSIs.

Covid-19: acquired acute porphyria?

Pandemic Covid-19 pneumonia, of SARS-CoV-2 aetiology, is of global importance to health systems, national economies, and individual civil liberties. Multiple therapeutic and prophylactic agents are currently undergoing clinical trial and, while progress towards a curative agent is promising, the principal limiting factor in public health emergency is time. A pre-existing licensed therapeutic would offer reprieve to international citizens currently enduring the adverse consequences of lockdown policies. The current review advances the author’s original hypothesis and advocates direct testing of the hypothesis by urinalysis of light-protected samples from critical Covid-19 patients to check for elevated aminolevulinic acid and porphobilinogen.

Three-dimensional Time-domain Induced Polarization of a Desert Aridisol for Septic Design

Septic leach field design in the arid southwestern US requires direct testing of soils to ensure adequate drainage. We propose that direct testing costs can be reduced if electrical geophysical methods are used to determine soil structure that facilitates proper drainage rates. We demonstrate this concept at a residential site where resistivity and induced polarization data were acquired within a desert soil with variable mixtures of clay (Argid) and calcareous (Orthid) components. Electrode arrays were tested to ensure high data quality and minimal workload during inversion modeling. The resulting resistivity structure identified a sharp boundary between the eastern and western halves of the property. The west was more conductive than the east, which could indicate the presence of higher moisture or higher clay content. Chargeability data gathered from the induced polarization survey showed similar stark patterns between east and west halves of the property. The western portion of the survey area was verified to have some clay based on high chargeability values and direct soil testing from pits. Test pits dug to 3.65 m showed transitions between Argid and Othid conditions; the test pits were in locations of moderate resistivity and low chargeability. From this study, we concluded that resistivity and IP were useful in septic design because they reduce the total amount of direct testing needed when testing locations are carefully chosen based on the geophysical results.

Detection of KPC, NDM and VIM-Producing Organisms Directly from Rectal Swabs by a Multiplex Lateral Flow Immunoassay

We report a preliminary evaluation of the NG-Test CARBA 5 immunochromatographic assay for detecting carbapenemases directly from rectal swabs on the same day of sampling. Thirty fecal swabs were examined for carbapenemase-producing organisms (CPOs) by conventional culture, PCR, and NG-Test CARBA 5. Each sample was tested by the immunochromatographic assay five times, including direct testing and incubation in trypticase soy broth for 1, 2, 3, and 4 h. Twenty patients yielded CPOs by culture. Immunochromatographic and PCR results were concordant and detected the same 25 carbapenemases (11 KPC, 8 VIM, and 6 NDM). In five cases, we detected co-carriage of KPC and VIM. Compared with PCR, the sensitivity of NG-Test CARBA 5 for the detection of KPC, VIM, and NDM was 80% without incubation, 88% with one hour, 92% with two, and 100% with three hours incubation, while specificity was 100% for all time points. All samples containing adequate fecal content were detected by NG-Test CARBA 5 concordantly with PCR, without incubation. NG-Test CARBA 5 is a reliable test that rapidly detects the presence of carbapenemases at the same day of sampling, directly from rectal swabs. It thus provides early information to guide antimicrobial treatment and infection control interventions.

Model-Based Re-Examination of the Effectiveness of Tumor/Immunohistochemistry and Direct-to-Sequencing Protocols for Lynch Syndrome Case Finding in Endometrial Cancer

PURPOSE: Despite widespread provision of Lynch syndrome (LS) screening programs, questions remain about the most effective and efficient protocol for LS case finding. The purpose of this study was to explore the performance of the two protocols widely shown to be the most efficient and effective, respectively: immunohistochemical (IHC) staining of tumor and direct-to-sequencing (DtS) in endometrial cancer populations. METHODS: Simulation models were developed to explore performance of the IHC and DtS protocols, updated to reflect current evidence. Analyses explicitly account for protocol complexity and failure points, as well as decreased sequencing costs. Key outcomes are percent of LS cases identified, total protocol costs and efficiency, and break-even analyses of sequencing costs. All costs are in 2020 US dollars (USD). RESULTS: Under plausible conditions, the IHC protocol is expected to identify 40%-78% of LS cases and DtS protocol from 49% to 97%. When the key variable success in proceeding to sequencing is fixed for both protocols at 50%, 75%, and 100%, the DtS protocol is 9%, 12%, and 16% better at case finding, respectively, than the IHC protocol. The break-even cost of sequencing is about $488 USD when the outcome is total direct testing protocol costs; it is about $670 USD when the outcome is cost per LS case detected. CONCLUSION: This study quantifies the plausible differences in the clinical effectiveness and cost-effectiveness of the two LS case-finding protocols. We demonstrate the large influence of success in proceeding to sequencing and potential impact of decreasing sequencing prices.

Prototype of Rainfall Intensity Measurement Using CCD TSL1401CL Linear Sensor Array

A prototype measurement of rainfall intensity was developed using a CCD TSL1401CL linear sensor array. The prototype consists of a He-Ne laser that functions as a light source, which later is focused by the beam expander and conditioned by a convex lens. Each pixel will receive the same voltage depending on the light intensity so that it produces a decimal value of ADC. This ADC decimal value determines rainfall intensity based on the diameter and velocity of the raindrops. The diameter variations used ranges from 1 mm to 10 mm, while for variations in the height of rainfall are 50 cm, 100 cm, and 150 cm. The test results proved that the greater the decimal value of the ADC is, the smaller the diameter of the raindrops detected will be, and vice versa. The values of the diameter and velocity of were used to obtain the value of rainfall intensity. The percentage value of error measuring rainfall intensity is 3.11% when compared to the rain gauge module is still considered rather accurate. However, direct testing is still needed when rain falls with various types and intensities.

Investigation on Slagging Fouling Potential in Coal Blending for PLTU with PC Boiler with Droptube Furnace Method

The majority of power plants in Indonesia are Coal-Fired Power Plants (PLTU) which using coal as the main fuel. The coal used in the PLTU is coal that has been adjusted to the existing PLTU design. However, coal availability according to the initial design of the PLTU is running low and even almost non-existent. If the coal does not meet the PLTU design specifications is forced to be used as fuel, various problems will arise regarding to the capability and reliability of the power plant itself. Therefore, looking for coal alternatives that have similar specifications to the PLTU design is very important, to get these alternatives can be done by Blending coal from various specifications. The Blending product must be evaluated from various aspects, one of which is slagging and fouling. This research will focus on the aspects of slagging fouling resulting from the Blending of two different coals in terms of characteristics and specifications. Evaluation is carried out by taking samples and tested to make predictions based on AAS and AFT, burning in the Drop Tube Furnace (DTF), and performing SEM and XRD analysis of two coal Blending products. The results obtained are that the A and B Blending products are in an acceptable risk for direct testing on a larger scale (PLTU) or boiler simulator. However, Blending A has a greater potential for further research than Blending product B.