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Resistance to clarithromycin, a macrolide antibiotic used in the first-line treatment of Helicobacter pylori infection, is the most important cause of treatment failure. Although most cases of clarithromycin resistance in H. pylori are associated with point mutations in 23S ribosomal RNA (rRNA), the relationships of other mutations with resistance remain unclear. We examined possible new macrolide resistance mechanisms in resistant strains using next-generation sequencing. Two resistant strains were obtained from clarithromycin-susceptible H. pylori following exposure to low clarithromycin concentrations using the agar dilution method. Sanger sequencing and whole-genome sequencing were performed to detect resistance-related mutations. Both strains carried the A2142G mutation in 23S rRNA. Candidate mutations (T1495A, T1494A, T1490A, T1476A, and G1472T) for clarithromycin resistance were detected in the Mutant-1 strain. Furthermore, a novel mutation in the gene encoding for the sulfite exporter TauE/SafE family protein was considered to be linked to clarithromycin resistance or cross-resistance, being identified as a target for further investigations. In the Mutant-2 strain, a novel mutation in the gene that encodes DUF874 family protein that can be considered as relevant with antibiotic resistance was detected. These mutations were revealed in the H. pylori genome for the first time, emphasizing their potential as targets for advanced studies. [ABSTRACT FROM AUTHOR]

This study provides a kinetic examination of methanol steam reforming (MSR) over a Cu-based commercial catalyst (CuO/ZnO/Al 2 O 3 , Alfa Aesar) as a function of CH 3 OH and H 2 O partial pressures at 246 °C and 1 atm in a once-through flow reactor. A power rate law was used to best describe the experimental rate data by linear and non-linear regressions at the operating conditions where transport bottlenecks were eliminated. Comparison of the rate parameters indicated that a strong correlation was suggested by non-linear regression giving reaction orders of 0.29 for methanol and 0.09 for water along with a frequency factor of 53.48 (mol CH3OH s−1 g catalyst −1 kPa−0.38) and an activation energy of 65.59 kJ mol−1. A simulation study of the rate equation to analyze an integrated system of a reformer and an HT-PEMFC was also conducted. The results demonstrate that the system has the potential to produce 15 W power output. • Kinetic analysis of methanol steam reforming on a commercial CuO/ZnO/Al 2 O 3 catalyst (HiFUEL®W220, Alfa Aesar) is reported. • A power rate law is used to best describe the experimental rate data by non-linear regression. • Aspen Plus is used to simulate the integrated system of a reformer and a HT-PEMFC to produce 15 W power output. [ABSTRACT FROM AUTHOR]

Herein, a performance analysis of La-doped copper-based catalysts (CuO/ZrO2/La-Al2O3) in methanol steam reforming (MSR) was conducted and compared with a commercial low temperature water-gas shift catalyst (HiFUEL W220) to produce H2 with low CO selectivity. The physicochemical properties of as-obtained catalysts were characterized by N2 adsorption, XRD, and ICP-OES. Effect of calcination temperature (750 and 1000) on the properties of mixed oxide support (La-Al2O3) were discussed based on catalytic activity. The optimum conditions of H2O/CH3OH ratio (1.0-3.0), space-time ratio (WFA0) (40-120 kg s mol-1), and reaction temperature (180-310) were evaluated by a parametric study using the commercial catalyst (HF220). Additionally, thermodynamic equilibrium calculations of experimentally identified components by using Aspen HYSYS process simulation software were also performed to analyze MSR process. The results were indicated that the calcination temperature significantly affected the structural properties and the activity with respect to CO selectivity. An increasing trend in CO selectivity for catalysts with supports calcined at 750 and a decreasing trend for catalysts with supports calcined at 1000 were observed. Hence, CZ30LA750 and CZ30LA1000 catalysts were selected to attain low CO selectivity and comparable activity when compared to other catalysts and the simulated thermodynamic calculation results. [ABSTRACT FROM AUTHOR]

Simple Summary: Cancer is one of the leading causes of death worldwide. Colorectal cancer belongs to the group of the most malignant tumors for which their burden can be only reduced through early detection and appropriate treatment. Increasing evidence indicates that the intestine microbiota is related and can impact colorectal carcinogenesis. This study proposes a multidisciplinary approach of two-phase methodology for modeling and interpreting the key biomarkers that can play a significant role in understanding the drug-resistant mechanism for patients diagnosed with colorectal cancer. The proposed methodology was evaluated using a publicly accessible dataset, which may serve clinicians as a complementary analysis tool in colorectal cancer diagnostics and therapeutics. This study contributes to the field of predictive modeling in healthcare. Recent studies have highlighted that gut microbiota can alter colorectal cancer susceptibility and progression due to its impact on colorectal carcinogenesis. This work represents a comprehensive technical approach in modeling and interpreting the drug-resistance mechanisms from clinical data for patients diagnosed with colorectal cancer. To accomplish our aim, we developed a methodology based on evaluating high-performance machine learning models where a Python-based random forest classifier provides the best performance metrics, with an overall accuracy of 91.7%. Our approach identified and interpreted the most significant genera in the cases of resistant groups. Thus far, many studies point out the importance of present genera in the microbiome and intend to treat it separately. The symbiotic bacterial analysis generated different sets of joint feature combinations, providing a combined overview of the model's predictiveness and uncovering additional data correlations where different genera joint impacts support the therapy-resistant effect. This study points out the different perspectives of treatment since our aggregate analysis gives precise results for the genera that are often found together in a resistant group of patients, meaning that resistance is not due to the presence of one pathogenic genus in the patient microbiome, but rather several bacterial genera that live in symbiosis. [ABSTRACT FROM AUTHOR]

In this study, a comparative thermodynamic equilibrium calculation of biogas oxy-reforming and oxy-steam reforming processes to produce syngas has been conducted by Aspen Plus simulation software. The effects of temperature (600–800°C), pressure (1−20 atm), and inlet O2/CH4 (0−1.0), H2O/CH4 (0−3.0), and CO2/CH4 (0.3−1.0) mole ratios on the equilibrium compositions of products were determined. The operation of the process was optimized using Gibbs free energy minimization method and statistical approach: response surface methodology (RSM). Optimum operating conditions CH4/CO2/O2 = 1:0.51:0.12 at 788°C and 1 atm for oxy-reforming and CH4/CO2/H2O/O2 = 1:0.63:0.19:0.07 at 780°C and 1 atm for oxy-steam reforming were obtained to reach maximum H2 yield, CH4 and CO2 conversions by minimizing carbon selectivity to produce syngas for methanol production. [ABSTRACT FROM AUTHOR]

A statistical modeling and optimization study on the thermodynamic equilibrium of methanol steam reforming (MSR) process was performed by using Aspen Plus and the response surface methodology (RSM). The impacts of operation parameters; temperature, pressure and steam-to-methanol ratio (H 2 O/MeOH) on the product distribution were investigated. Equilibrium compositions of the H 2 -rich stream and the favorable conditions within the operating range of interest (temperature: 25–600 °C, pressure: 1–3.0 atm, H 2 O/MeOH: 0–7.0) were analyzed. Furthermore, ideal conditions were determined to maximize the methanol conversion, hydrogen production with high yield and to minimize the undesirable products such as CO, methane, and carbon. The optimum corresponding MSR thermodynamic process parameters which are temperature, pressure and H 2 O/MeOH ratio for the production of HT-PEMFC grade hydrogen were identified to be 246 °C, 1 atm and 5.6, respectively. • Influence of steam-to-methanol ratio, temperature, and pressure on equilibrium conditions was investigated. • Optimization of process parameters was performed by response surface methodology (RSM). • Optimum temperature, pressure and H 2 O/MeOH ratio for Case-1 were identified to be 246 °C, 1 atm and 5.6 respectively. • CO production was reached to very low values of 30–1700 ppm (mole) (dry basis) which can be tolerated by HT-PEMFC systems. [ABSTRACT FROM AUTHOR]

A response surface methodology (RSM) was implemented to investigate the effect of sol-gel synthesis variables in the structural and textural properties of boron doped alumina synthesis. The effects of four independent operating variables (mol HNO 3 /mol AIP, concentration of AIP, mol H 2 O/mol AIP, and boron weight/total catalyst support weight) were explored on the responses, namely the total surface area, and the BJH desorption pore diameter of boron doped alumina (B-Al 2 O 3 ) supports. The variables were optimized and the models were validated by the experimental runs which were synthesized by simultaneously adjusting the operating variables giving maximum deviation of 3.3% from the desired value. The synthesized samples were characterized by XRD, BET, SEM, ICP-OES and TEM techniques. The characterization studies pointed out the interactions between process variables significantly affect the morphology of the catalyst support. The morphology of the supports can be modified from cracked surface to nano-sphere formation by the introduction of boron. [ABSTRACT FROM AUTHOR]

Members of the family Iridoviridae (iridovirids) are large dsDNA viruses that infect both invertebrate and vertebrate ectotherms and whose symptoms range in severity from minor reductions in host fitness to systemic disease and large-scale mortality. Several characteristics have been useful for classifying iridoviruses; however, novel strains are continuously being discovered and, in many cases, reliable classification has been challenging. Further impeding classification, invertebrate iridoviruses (IIVs) can occasionally infect vertebrates; thus, host range is often not a useful criterion for classification. In this review, we discuss the current classification of iridovirids, focusing on genomic and structural features that distinguish vertebrate and invertebrate iridovirids and viral factors linked to host interactions in IIV6 (Invertebrate iridescent virus 6). In addition, we show for the first time how complete genome sequences of viral isolates can be leveraged to improve classification of new iridovirid isolates and resolve ambiguous relations. Improved classification of the iridoviruses may facilitate the identification of genus-specific virulence factors linked with diverse host phenotypes and host interactions. [ABSTRACT FROM AUTHOR]

We present a global atlas of 4,728 metagenomic samples from mass-transit systems in 60 cities over 3 years, representing the first systematic, worldwide catalog of the urban microbial ecosystem. This atlas provides an annotated, geospatial profile of microbial strains, functional characteristics, antimicrobial resistance (AMR) markers, and genetic elements, including 10,928 viruses, 1,302 bacteria, 2 archaea, and 838,532 CRISPR arrays not found in reference databases. We identified 4,246 known species of urban microorganisms and a consistent set of 31 species found in 97% of samples that were distinct from human commensal organisms. Profiles of AMR genes varied widely in type and density across cities. Cities showed distinct microbial taxonomic signatures that were driven by climate and geographic differences. These results constitute a high-resolution global metagenomic atlas that enables discovery of organisms and genes, highlights potential public health and forensic applications, and provides a culture-independent view of AMR burden in cities., Competing Interests: Declaration of interests C.E.M. is co-founder of Biotia and Onegevity Health. D.B. is co-founder and CSO of Poppy Health Inc. The other authors declare they have no competing interests that impacted this study., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

Leishmania virus (LRV) has previously been identified in different Leishmania species. Host-LRV interaction is associated with exacerbated clinical manifestations of cutaneous leishmaniasis (CL) and may cause poor therapeutic response. CL cases due to L. major with large skin lesions resistant to routine therapy were recently identified in Turkey. Here, we report the first autochthonous case of cutaneous leishmaniasis caused by LRV-positive Leishmania major, using conventional PCR targeting the viral capsid protein of LRV. The lesion of the case was 6 months old, relatively large (4 cm), and did not recover despite three consecutive intralesional applications of glucantime. Assessment of LRV's influence on prognosis and clinical outcomes of leishmaniasis, based on additional studies, is required.