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Background: One main challenge in Helicobacter pylori (H. pylori) eradication is its increasing antibiotic resistance. Additionally, resistance rates vary between geographic areas and periods. However, data are limited since susceptibility testing is not routinely performed. Thus, it is valuable to gather data regarding H. pylori's resistance rates in Israel that would aid in better adjustment of treatment. Materials and Methods: The study included 540 H. pylori isolates, recovered from gastric biopsy samples of patients who had undergone endoscopy, during 2015–2020, at the Padeh Poriya Medical Center. Antibiotic susceptibility testing to amoxicillin, clarithromycin, metronidazole, levofloxacin, rifampicin, and tetracycline was performed using the Etest technique. Data regarding participants' sex, age, and ethnic group were collected. For every antibiotic and for multi‐resistance, generalized linear models were used to estimate crude and adjusted estimated differences in mean MIC and odds ratios (ORs) for every year, compared with the reference year 2015. Results: The highest resistance rates were for clarithromycin and metronidazole (46.3% and 16.3%, respectively). Patients above 18 had higher resistance rate to rifampicin and multi‐resistance (3.3% and 14.8%), compared with patients under 18 (0.5% and 8.4%, respectively). Resistance rates for levofloxacin, rifampicin, and multi‐resistance were significantly higher among Arab patients, compared with Jewish patients. During the 6‐year surveillance, a significant annual trend in MIC for metronidazole and in ORs for metronidazole, levofloxacin, and multi‐resistance were observed (after adjustment). During 2020 compared with 2015, significant increased ORs were observed for levofloxacin and metronidazole [5.72 (1.03–31.84); 4.28 (1.30–14.14), respectively]. Conclusions: In light of the remarkable changes in antibiotic resistance of H. pylori during the study's period and the increasing resistance rates to various antibiotics, it is very important to continuously monitor H. pylori antibiotic susceptibly. In order to increase eradication rates of this bacterium, therapy regimes must be based on an updated antibiotic resistance data. [ABSTRACT FROM AUTHOR]

BACKGROUND Tetranychus urticae is a notorious crop pest with a worldwide distribution that has developed resistance to a wide range of acaricides. Here, we investigated the resistance levels of a T. urticae population collected from an ornamental greenhouse in Peloponnese, Greece, and analyzed its resistance mechanisms at the molecular level. RESULTS: Toxicological assays showed resistance against compounds with different modes of action, with resistance ratios of: 89‐fold for abamectin; > 1000‐fold for clofentezine; > 5000‐fold for etoxazole; 27‐fold for fenpyroximate and pyridaben; 20‐ and 36‐fold for spirodiclofen and spirotetramat, respectively; and 116‐ and > 500‐fold for cyenopyrafen and cyflumetofen, respectively. Bioassays with synergists indicated the involvement of detoxification enzymes in resistance to abamectin, but not to cyflumetofen and spirodiclofen. RNA sequencing (RNA‐seq) analysis showed significant over‐expression of several genes encoding detoxification enzymes such as cytochrome P450 monooxygenases and UDP‐glycosyltransferases, which have been previously associated with acaricide resistance. Known target‐site resistance mutations were identified in acetyl‐choline esterase, chitin synthase 1 and NDUFS7/psst, but putative novel resistance mutations were also discovered in targets such as glutamate‐gated chloride channel subunit 3. Interestingly, target‐site resistance mutations against pyrethroids or bifenazate were not identified, possibly indicating a recent reduced selection pressure in Greece, as well as a possible opportunity to rotate these chemistries. CONCLUSION: We identified and characterized a striking case of multiple acaricide resistance in a field population of T. urticae. Exceptionally strong resistance phenotypes, with accumulation of multiple resistance mutations and over‐expression of P450s and other detoxification genes in the same field population are reported. [ABSTRACT FROM AUTHOR]

Gram‐negative germs with and without multi‐resistance are garnering more and more importance. The aim of this study was to investigate the frequency and rate of resistance against antibiotics and to clarify the impact of Gram‐negative bacteria, especially with high rates of resistance, for the treatment of venous leg ulcers. This is a retrospective, monocentric, non‐randomised open study. Included were all data within 1 year of bacterial swabs of venous leg ulcers. We performed summarization, pooling, and descriptive analysis for frequencies and crossover. We analysed 679 swabs of 285 patients with venous leg ulcers. The mean patient age was 69.78 years. There were 76.1% Gram‐positive and 58.2% Gram‐negative germs detected; 56.5% of the swabs showed multi‐resistance. Gram‐negative bacteria were associated with more pain. Exacerbation and relevant aggravation of wounds that led to stationary treatment occurred more frequently. With polihexanid treatment, we saw less Gram‐negative flora. This study showed an immediate impact of Gram‐negative germs on the patient's pain, the risk for aggravation, and the choice of treatment. Further studies for prophylaxis and treatment of Gram‐negative germs in venous leg ulcer therapy are needed. [ABSTRACT FROM AUTHOR]

SummaryThe possible insecticide resistance mechanisms of four Malaysian field-collected strains of the German cockroach, Blattella germanica (Linnaeus) (Dictyoptera: Blattellidae), were characterized with biochemical assays and native polyacrylamide gel electrophoresis (PAGE). Elevated esterase activity (at low to moderate frequency) and altered acetylcholinesterase (low frequency) were detected in all field strains, while elevated glutathione S-transferase levels were present in only two strains. Seven esterase bands were separated by native PAGE; a greater intensity occurred in three bands in the resistant strains compared to the susceptible strain. Inhibition studies using specific inhibitors on polyacrylamide gels suggested that the slowest of these three esterases is a cholinesterase, while the other two are carboxylesterases with a preference for β- over α-naphthyl acetate. [ABSTRACT FROM AUTHOR]