Levels Of Resistance Research Articles

Evaluation of genetic diversity and genome-wide association studies of resistance to bacterial wilt disease in potato.

The development of novel improved varieties adapted to unstable environmental conditions is possible through the genetic diversity of breeding materials. Potato is among the most important food crops worldwide, however, there are still significant hindrances to breeding gains attributed to its autotetraploid and highly heterozygous genome. Bacterial wilt caused by the Ralstonia solanacearum species complex (RSSC) is an important disease affecting potato among many economically important crops worldwide. No cultivated potato genotypes have shown a satisfactory level of resistance to bacterial wilt. Nevertheless, resistance can play a crucial role in effective integrated disease management. To understand the genetic landscape of bacterial wilt resistance in cultivated potato, we evaluated the diversity of 194 accessions from the International Potato Centre (CIP) using 9,250 single nucleotide polymorphisms (SNPs) and their associations to the response to bacterial wilt disease evaluated over two independent trials. Twenty-four accessions showed high resistance throughout both trials. Genetic diversity analysis revealed three major clusters whose subgroups were mostly represented by CIP clones derived from common parents. Genome-wide association analyses have shown six major hits: two on chromosome 8, and one on each chromosome 2, 4, 5, and 9. These results facilitate genetic dissection of bacterial wilt resistance and marker-enabled breeding in elite genotypes for potato breeding initiatives.

Longitudinal genomic surveillance of a UK intensive care unit shows a lack of patient colonisation by multi-drug-resistant Gram-negative bacterial pathogens.

Vulnerable patients in an intensive care unit (ICU) setting are at high risk of infection from bacteria including gut-colonising Escherichia coli and Klebsiella species. Complex ICU procedures often depend on successful antimicrobial treatment, underscoring the importance of understanding the extent of patient colonisation by multi-drug-resistant organisms (MDROs) in large UK ICUs. Previous work on ICUs globally uncovered high rates of colonisation by transmission of MDROs, but the situation in UK ICUs is less understood. Here, we investigated the diversity and antibiotic resistance gene (ARG) carriage of bacteria present in one of the largest UK ICUs at the Queen Elizabeth Hospital Birmingham (QEHB), focusing primarily on E. coli as both a widespread commensal and a globally disseminated multi-drug-resistant pathogen. Samples were taken during highly restrictive coronavirus disease 2019 (COVID-19) control measures from May to December 2021. Whole-genome and metagenomic sequencing were used to detect and report strain-level colonisation of patients, focusing on E. coli sequence types (STs), their colonisation dynamics and antimicrobial resistance gene carriage. We found a lack of multi-drug resistance (MDR) in the QEHB. Only one carbapenemase-producing organism was isolated, a Citrobacter carrying bla KPC-2. There was no evidence supporting the spread of this strain, and there was little evidence overall of nosocomial acquisition or circulation of colonising E. coli. Whilst 22 different E. coli STs were identified, only 1 strain of the pandemic ST131 lineage was isolated. This ST131 strain was non-MDR and was found to be a clade A strain, associated with low levels of antibiotic resistance. Overall, the QEHB ICU had very low levels of pandemic or MDR strains, a result that may be influenced in part by the strict COVID-19 control measures in place at the time. Employing some of these infection prevention and control measures where reasonable in all ICUs might therefore assist in maintaining low levels of nosocomial MDR.

Evaluation of the Toxicity of Glyphosate and its Impact on the Tolerance of Ancistrotermes guineensis to Chlorpyrifos-ethyl and the Methanolic Extract of Tithonia diversifolia

The massive use of glyphosate as a means of weed control is increasingly observed in cocoa plantations in Ivory Coast. Added to this is the ineffectiveness of the treatments. These observations led us to evaluate the level of resistance of A. guineensis to Chlorpyrifos-ethyl and T. diversifolia extract after exposure to glyphosate. The toxicity of glyphosate on A. guineensis workers was evaluated by direct toxicity. For the evaluation of the impact of glyphosate on the tolerance of A. guineensis workers, 50 workers taken at random from 75 workers previously exposed to glyphosate for 4, 6, 12 and 24 hours at concentrations 1.9, 2.14 and 3.56 g/l, were used for the bioassays with Chlorpyrifos-ethyl (22.4 mg/l) and T. diversifolia extract (10 mg/l). The study revealed no toxicity of glyphosate on A. guineensis workers. On the other hand, it showed that the exposure of workers of A.guineensis to glyphosate could modify their sensitivity to Chlorpyrifos-ethyl. This modification begins 4 hours after contact with glyphosate and at the lowest concentration. Tolerance of A. guineensis workers to Chlorpyrifos-ethyl is linked to the duration of exposure to glyphosate. After 24 hours of Chlorpyrifos-ethyl treatment, the mortality of unexposed workers and those exposed (4 and 24 hours) to glyphosate (1.9g/l) was respectively 60.00±3.65, 23.00± 1.9 and 15.00±1.15. Unlike Chlorpyrifos-ethyl, the study revealed no impact of glyphosate on the sensitivity of A. guineensis workers to the T. diversifolia extract. After 24 bioassays with T. diversifolia, the mortality of unexposed workers and those exposed (4 and 24 hours) to glyphosate (1.9g/l) was respectively 30.40±1.67, 30.40±1 .69 and 29.20±2.28. Given the cases of resistance observed with chemical products, the fight against termites must be done with natural plant extracts.

Study on resistance performance of hexagonal hull form with variation of angle of attack, deadrise, and stern for flat-sided catamaran vessel

Abstract The flat-sided hull vessel was designed with the purpose of simplifying hull production by eliminating the requirement for fairing, bending, and assembly of curved panel lines. Nevertheless, implementing the flat hull concept may marginally increase the hull resistance. The objective of the study is to investigate the impact of the hexagonal hull concept on resistance characteristics when altering the deadrise angle, angle of attack, and stern angle. Additionally, the resistance performances of the proposed hexagonal hulls were compared to evaluate the influence of the hull design geometry parameter. The contribution of this work is to identify the configuration of the design parameters to achieve an ideal level of resistance in a hexagonal catamaran hull design. The findings indicate that a greater angle of attack could potentially enhance wave generation and increase the resistance. Despite the increase in the wave resistance coefficient caused by the increment in deadrise angle, the overall resistance was reduced due to the significant reduction in wetted surface area resulting from the greater deadrise angle. As a result, the decrease in friction resistance was more pronounced than the increase in wave resistance. At last, the stern angle can cause a substantial oscillation in the curved line, resulting in a large increase in wave generation and overall resistance, particularly at high speeds.

Myroides species, pathogenic spectrum and clinical microbiology sight in Mexican isolates.

Myroides is a bacterial genus of opportunistic bacteria responsible for diverse infections including in the skin and soft tissues, urinary tract, cardiovascular system, and bacteremia, although the incidence of its reported infections is low, it is increasing, likely due the use of better bacterial identification methods, but also perhaps due an increase in its prevalence. In addition, their pathogenic role is limited in terms of reporting their microbial physiology, so the present work provides information in this regard in addition to the information that is available in the international literature. To describe the microbiological and genetic characteristics of seven different Myroides spp. clinical strains and comment on their phylum, pathogenic and resistance characteristics. Seven Myroides spp., strains associated with infections were included from 1/January/2012 to 1/January/20 and identified by miniaturized biochemistry and MALDI-ToF. Susceptibility tests were performed according to CLSI recommendations by broth microdilution. Whole genome sequencing was performed for each strain and bioinformatics analysis were performed. Strains were identified at genus level by two methodologies. Our results revealed that likely four strains belong to the species Myroides odoratimimus, while the other two may be undescribed ones. Remarkably, all isolates harbored several genes encoding antibiotic resistance determinants for ß-lactams, aminoglycosides and glycopeptides and in concordance, presented high levels of resistance, against these antibiotics (AK and GN both 100%, ATM, CAZ and FEP 100%, e.g.); moreover, the presences of carbapenemases were evidenced by meropenem (mCIM) and imipenem (CARBA NP) degrading activity in six isolates and two strains possessed plasmids harboring mainly ribosomal RNA genes, tRNAs and genes encoding proteins with unknown functions. Our study increases the knowledge about the biology of this understudied genus and highlights the potential of Myroides to emerge as a broader cause of recalcitrant opportunistic infections.

What role does antibiotic resistance play in secondary endodontic infections?

The systematic review utilised multiple electronic databases to gather relevant literature, including PubMed, Scopus, EMBASE, Web of Science, and Medline. The search was conducted focusing on clinical studies where Enterococcus strains were isolated to assess their antimicrobial resistance. The search strategy was designed based on the PICO model, targeting patients with secondary/persistent endodontic infections (SPEI) and evaluating the resistance profiles of Enterococci to systemic antibiotics. A total of 584 studies were initially identified through database searches. After removing duplicates, 517 studies were excluded based on title and abstract screening, leading to the final inclusion of 11 clinical trials that met the eligibility criteria. The studies were conducted in various countries, including Brazil, Lithuania, Poland, Germany, Sweden, the United States, and Japan. The focus was on permanent teeth with post-treatment apical periodontitis undergoing endodontic retreatment. Data extraction was performed independently by two reviewers, who compiled details such as authorship, year of publication, country of study, sample groups, bacterial strains tested, antibiotics used, and resistance outcomes. The risk of bias was assessed using the ROB-2 platform, and all studies were considered to have a low risk of bias, with occasional minor deficiencies noted. The analysis revealed fluctuating resistance profiles of Enterococcus faecalis (E. faecalis) and Enterococcus faecium (E. faecium) to various antibiotics over time. E. faecalis isolated from teeth with SPEI showed intermediate resistance to 16 antibiotics. The most effective antibiotics identified were the combination of amoxicillin and clavulanate, followed by amoxicillin and benzylpenicillin. In patients with penicillin allergies, moxifloxacin and azithromycin were suggested as alternatives, albeit with caution due to their varying resistance levels. The antibiotics demonstrating the highest resistance patterns against E. faecalis included clindamycin, gentamicin, metronidazole, and rifampicin, which are contraindicated in SPEI cases. Ongoing monitoring of antibiotic resistance patterns is crucial for effective endodontic treatment protocols. The emergence of resistance among Enterococci, particularly E. faecalis, necessitates regular susceptibility testing to inform clinical decisions and improve treatment outcomes. The findings underscore the need for health professionals to stay informed about the evolving resistance landscape to ensure safe and effective therapeutic regimens in endodontics.

Establishing a Female Animal Model of Prediabetes Using a High-Carbohydrate, High-Fat Diet

Prediabetes is a condition that often precedes the onset of type 2 diabetes and is characterized by moderate levels of insulin resistance. This condition is well established in male animal models for diabetes; however, few female models exist. There is accumulating evidence that sex variations affect the pathogenesis, treatment, and consequences of numerous diseases, such as type 2 diabetes. Therefore, we sought to develop a diet-induced prediabetic female animal model to better understand prediabetes development and its effects in females. Female Sprague Dawley rats were randomly allocated to one of two groups: the standard diet (SD) group fed a standard diet with normal drinking water, and the high-carbohydrate, high-fat (HCHF) group fed a high-carbohydrate and high-fat diet with drinking water supplemented with fructose. During induction, we measured food intake, body weight, body mass index (BMI), and oral glucose tolerance response (OGT). After the induction period, biochemical analyses were conducted to assess the levels of plasma leptin, ghrelin, insulin, and glycated hemoglobin (HbA1c). Glycogen concentrations were quantified in the liver and skeletal muscles. The HCHF diet-fed group presented higher body weight gain, food intake, and BMI levels, which were accompanied by elevated plasma insulin, ghrelin, and liver and skeletal muscle glycogen levels compared to the SD-fed group. In the HCHF diet-fed group, the HOMA-IR was above 1.9, suggesting the presence of moderate levels of insulin resistance. The OGT response was significantly higher in the HCHF-fed group versus the SD-fed group, suggesting impaired glucose tolerance, thus displaying the signs and symptoms of prediabetes. The HCHF diet with fructose led to the induction of prediabetes in female Sprague Dawley rats. This model could be used to investigate and outline the pathophysiological complications associated with prediabetes in females as a result of the prolonged ingestion of a high carbohydrate, high-fat diet with fructose. The development of this model could also serve as an effort to further bridge the gap regarding the inclusion of females in biomedical research, thus providing advancements in deriving better, specified treatment strategies for women.

Causative Agents and Antibiotic Resistance in Nosocomial Sepsis: A Cross-Sectional Multicenter Study from Isfahan Province, Iran

Background: Nosocomial sepsis is a leading cause of morbidity and mortality worldwide. Understanding the antibiotic susceptibility patterns of pathogens specific to each geographic region is essential for effective patient management. Methods: This cross-sectional study aimed to investigate the microorganisms causing nosocomial sepsis and their antibiotic sensitivity in patients admitted to three referral hospitals in Isfahan, Iran. Clinical information and blood culture results were obtained from hospital records. Results from patients without signs of sepsis, as well as contaminants and community-acquired isolates, were excluded. Stratification was conducted based on sex and age (< 20 and > 20 years) categories. Results: In this study, 267 patients with hospital-acquired sepsis were identified, with gram-negative bacteria accounting for 77.2% of infections. The most common pathogens included Klebsiella spp. (35.2%), Acinetobacter spp. (21.7%), Enterococcus spp. (13.5%), Escherichiacoli (8.6%), Pseudomonasaeruginosa (8.6%), and Staphylococcusaureus (8.2%). The highest resistance among gram-negative bacteria was observed with cefepime (80.3%), ceftazidime (76.5%), cefotaxime/ceftriaxone (70.0%), trimethoprim-sulfamethoxazole (68.6%), ciprofloxacin (68.2%), meropenem (60.0%), and amikacin (50.3%). All gram-negative isolates were sensitive to colistin. Among gram-positive bacteria, the highest resistance was to ciprofloxacin (77.3%), ampicillin (75.7%), clindamycin (74.4%), vancomycin (64.9%), and gentamicin (30.0%). All gram-positive isolates in this study were sensitive to linezolid. Conclusions: The study indicates a high level of resistance among bacterial agents causing nosocomial sepsis in the studied area. Consequently, treatment may necessitate the use of last-line antibiotics, such as linezolid and colistin.

Listeria monocytogenes in Fruits and Vegetables: Antimicrobial Resistance, Biofilm, and Genomic Insights

Background/Objectives: Listeria monocytogenes is a foodborne pathogen that can infect both humans and animals and cause noninvasive gastrointestinal listeriosis or invasive listeriosis. The objectives of this study were to determine the genetic diversity of L. monocytogenes; the genes associated with its resistance to antibiotics, benzalkonium chloride (BC), and cadmium chloride (CdCl2); and its biofilm formation. Methods: A total of 132 fresh fruits (44 samples) and vegetables (88 samples) were selected for this study. The genetic diversity of the isolates and the genes associated with their antibiotic resistance were determined using PCR amplification; meanwhile, their levels of susceptibility to antibiotics were determined using the agar diffusion method. Their levels of resistance to BC and CdCl2 were determined using the minimum inhibitory concentration method, and their capacity for biofilm formation was evaluated using the crystal violet staining method. Results: A total of 17 L. monocytogenes strains were collected: 12.8% (17/132) from fresh fruits and vegetables in this study. The isolates of L. monocytogenes belonged to phylogenetic groups I.1 (29.4% (5/17); serotype 1/2a) and II.2 (70.5% (12/17); serotype 1/2b); strains containing Listeria pathogenicity islands (LIPIs) were also identified at prevalence rates of 100% for LIPI-1 and LIPI-2 (17/17), 29.4% for LIPI-3 (5/17), and 11.7% for LIPI-4 (2/17). The antibiotic susceptibility tests showed that the L. monocytogenes isolates exhibited six different multiresistant patterns, with multiple antibiotic resistance (MAR) index of ≥0.46 (70.5%; 12/17); additionally, the genes Ide, tetM, and msrA, associated with efflux pump Lde, tetracycline, and ciprofloxacin resistance, were detected at 52.9% (9/17), 29.4% (5/17), and 17.6% (3/17), respectively. The phenotypic tests showed that 58.8% (10/17) of cadmium-resistant L. monocytogenes isolates had a co-resistance of 23.5% (4/17) to BC. Finally, all strains of L. monocytogenes exhibited moderate biofilm production. Conclusions: The results of this study contribute to our understanding of the persistence and genetic diversity of L. monocytogenes strains isolated from fresh fruits and vegetables; in addition, their resistance to CdCl2, which is correlated with co-resistance to BC disinfectant, is helpful for the food industry.

Estimating TYLCV resistance level using RGBD sensors in production greenhouse conditions

Automated phenotyping is the task of automatically measuring plant attributes to help farmers and breeders in developing and growing strong robust plants. An automated tool for early illness detection can accelerate the process of identifying plant resistance and quickly pinpoint problematic breeding. Many such phenotyping tasks can be achieved by analyzing images from simple, low cost, RGB-D sensors. In this paper we focused on a particular case study — identifying the resistance level of tomato hybrids to the tomato yellow leaf curl virus (TYLCV) in production greenhouses. This is a difficult task, as separating between resistance levels based on images is difficult even for expert breeders. We collected a large dataset of images from an experiment containing many tomato hybrids with varying resistance levels. We used the depth information to identify the topmost part of the tomato plant. We then used deep learning models to classify the various resistance levels. For identifying plants with visual symptoms, our methods achieved an accuracy of 0.928, a precision of 0.934, and a recall of 0.95. In the multi-class case we achieved an accuracy of 0.76 in identifying the correct level, and an error of 0.278. Our methods are not particularly tailored for the specific task, and can be extended to other tasks that identify various plant diseases with visual symptoms such as ToBRFV,mildew, ToMV and others.

Wear behaviour of T4 and T6 heat treated LM28 composite reinforced with ZrO2 particles by stir casting method

Abstract The current study was performed to investigate the metal alloy LM28’s wear characteristics, strengthened by fine and coarse ZrO2 were investigated after undergoing thermal treatment with T4 and T6 process. Aluminium degasification tablets were used during the stir casting liquid metallurgy process to produce the composites with less porosity. ZrO2 was employed as fine (10–30 μm) and coarse (80–120 μm) particles in a step size of 3% from 0 to 12 wt%. The traditional T4 and T6 HT process was applied to the composite materials (LM28 nZrO2). T4 heat treatment involved in elevating the composites to 450 °C for 120–180 min before quenching them into the oil and age them naturally for 8–42 days at ambient room temperature. T6 HT was performed in a routine fashion, but also underwent artificial aging at 190–240 °C for 3–7 h before normal cooling. When compared to T4 HT process and non-HT composites, the hardness of T6 HT composites gives better results against wear property. The ideal level of hardness and resistance to wear of the composite was found in T6 HT composites when tested with a pin on a disk throughout a range of sliding distances and loads. Scanning electron microscopy demonstrated that T4 HT and non-HT composites suffered more surface damage than T6 HT composites when subjected to the same load and sliding distance. Initially, material was removed by an abrasive wear process, but this shifted to an adhesive one as sliding distance increased. T6 thermal treated composites are ideal for usage in tough conditions as a result of their excellent hardness and resilience to wear.

Color and functionality construction of cellulose towels with biological Monascus pigment based on a nano-suspension system

As a sanitary textile that directly contacts sensitive parts of the human body, such as mouth, nose and eyes, towel is very important for our daily life and health. However, the colored cellulose towels we use daily are dyed with synthetic dyes. This can be a problem for people with sensitive skin, particularly babies. In this research, cellulose towel fabric was dyed using a nano-level Monascus pigment dyeing solution, which eliminated the need for organic solvent to dissolve the pigment, making it an environmentally friendly dyeing scheme. After 90 °C pre-mordanting treatment and 80 °C dyeing for 30 min respectively, the K/S value of towel fabric could reach 9. In addition, the washing fastness of dyed towel fabric was 3–4, the dry/wet friction fastness was 4–5 and 3–4, and the K/S value remained high even after 20 washing times, and also demonstrated a certain level of UV resistance and antibacterial properties. In conclusion, the application of the dyeing method for cellulose towel fabric with biological Monascus pigment based on a nano-suspension system was found to be both efficient and environmentally friendly, which was anticipated to replace certain traditional synthetic dyes in the future.

Barrier height modulation in Amorphous IGZO/Metal interface using Trichlorosilane-Based Self-Assembled monolayers

Amorphous InGaZnO (a-IGZO) has become a key material for thin-film transistors (TFTs) due to its high mobility, low leakage current, and optical transparency. However, the increasing demands for ultra-high-resolution displays, such as those required for virtual and augmented reality applications, pose challenges related to contact resistance and Fermi level pinning at the a-IGZO/metal interface, as TFTs are scaled down. To address these challenges, we investigated trichlorosilane-based self-assembled monolayers (SAMs) as an interfacial layer between a-IGZO and metal contacts (Al, Ag, and Ni). By employing SAMs with varying carbon chain lengths—methyl trichlorosilane (MTS), octyl trichlorosilane (OTS), and octadecyl trichlorosilane (ODTS)—we aimed to improve interface properties and reduce contact resistance. Our study comprehensively analyzed thermionic emission characteristics, including barrier height, saturation current, ideality factor, and contact resistance, across different metal electrodes. The results show that the SAM layers effectively modulate barrier height and Fermi level pinning, depending on the combination of SAM layers (MTS, OTS, and ODTS) and metal electrodes (Al, Ag, and Ni). Additionally, the study provides insights into the influence of SAM carbon chain length on direct tunneling current and interface passivation, and contributes to a deeper understanding of conduction mechanisms at a-IGZO/metal interfaces.

Using pack animals instead of tractors in Central Italy's protected areas: No evidence of reduced soil disturbance

In thinning operations in Mediterranean beech forests, pack animals are often used when topographic conditions do not allow for the use of mechanisation to perform logging operations. Otherwise, mechanised extraction is the primary choice. In an effort to reduce soil disturbance caused by mechanised ground-based logging, the forest authorities who guard protected areas have been mandating animal logging at all logging sites in recent years. Since no comparative scientific trials of soil disturbance of these two extraction systems have ever been conducted in the target setting, there is no scientific evidence to sustain this approach. On this basis, we chose two study areas where the forest authorities mandated animal logging. Each study area consists of three sub-compartments, one unharvested, one harvested by animals, and one harvested by tractor in the same year (2021). We examined soil compaction, soil organic matter, and soil microarthropod biodiversity in animal skid trails, tractor skid trails, soil unaffected by extraction methods, and unharvested control sites in each study areas. We used linear mixed-effects models, indicating the study area as random intercept, to investigate the effect of the experimental treatments on the target soil features, and to check the relationship among soil physico-chemical parameters and soil microarthropod biodiversity. We discovered that only the animal and tractor skid trails showed signs of disturbance in terms of soil compaction and organic matter loss. Additionally, there was a significant decline in the biodiversity of soil microarthropods in both the skid trail types, with values of the QBS-ar index which were practically halved in comparison to the control area. We did not find any significant difference in the values in the tractor and animal skid trails for any of the examined soil characteristics. Low soil microarthropod biodiversity was found to be correlated with high soil compaction in terms of penetration resistance and low soil organic matter levels, according to linear mixed-effects models. Despite our preliminary findings, we made it clear that the short wood system by a tractor fitted with forwarding bins is unquestionably a very soil-disturbing extraction system, that ought to be avoided when conducting logging operations in protected areas. However, pack animals are not a suitable solution to reduce soil disturbance. Other extraction systems such as chute, small-scale cable yarders, as well as combination of animals and machine avoiding extensive traffic on the forest soil, are better solutions to the fundamental issue of low-impact logging in protected areas.

High resistance levels to pyrimethanil and fludioxonil among fourteen Penicillium spp. from pome fruits in the U.S. Pacific Northwest

In this study, 162 Penicillium isolates, i.e., 31 P. expansum isolates and 131 isolates from 13 other Penicillium spp. referred to as “non-expansum” were collected from apples and pears from multiple packinghouses in Washington State and Oregon. The sensitivity of the isolates to the postharvest fungicides pyrimethanil (PYR) and fludioxonil (FDL) was assessed in vitro. The mean EC50 value for PYR was 0.75 μg/mL in P. expansum compared to 1.63, 3.47, 6.95, 7.06 and 32.21 μg/mL in P. solitum, P. palitans, P. commune, P. roqueforti and P. carneum, respectively. For FDL, the mean EC50 value was 0.04 μg/mL in P. expansum compared to >0.80, 1.00, 10.40, 13.99, and 158.10 μg/mL in P. commune, P. palitans, P. roqueforti, P. solitum, and P. paneum, respectively. Overall, > 40 % of isolates from five “non-expansum” species showed dual resistance to PYR and FDL versus 9.6 % in P. expansum. The recommended rates of PYR and FDL failed to control isolates of six Penicillium spp. on detached apples after five months at 1.5 °C. Sequencing of the Mdl1, NikA, and Os1 genes from different isolates of eight species revealed a high polymorphism in the Mdl1 and NikA of several “non-expansum” species. Three and two concurrent mutations, in addition to a G409R and S959, were detected in the Mdl1 and NikA, respectively, that potentially confer resistance to PYR and FDL. The high level of resistance and the control failure observed on fruits highlight the potential risk posed by several “non-expansum” Penicillium species to pome fruit packers.

Genetic characteristics and antimicrobial resistance of Staphylococcus aureus isolates from pig farms in Korea: emergence of cfr-positive CC398 lineage

BackgroundLivestock-associated Staphylococcus aureus (LA-SA) has gained global attention because of its ability to colonize farm animals and transmit to the environment and humans, leading to symptomatic infections and the spread of antimicrobial resistance (AMR). In the last decade, numerous studies have reported a high prevalence of S. aureus clonal complex (CC) 398 in pig farms.ResultsIn this study, 163 S. aureus isolates were collected from healthy pigs (n = 110), farm environments (n = 42), and farm workers (n = 11), and their AMR profiles and epidemiological characteristics were analyzed. We identified 51 (31.3%) methicillin-resistant S. aureus (MRSA) and 112 (68.7%) methicillin-susceptible S. aureus (MSSA), with 161 (98.8%) isolates belonging to the CC398 lineage. The highest prevalence of spa type t571 was observed among the CC398 isolates. All 47 sequence type (ST) 398 MRSA isolates carried staphylococcal cassette chromosome mec (SCCmec) V, while four ST541 isolates carried SCCmec IV. High levels of resistance to commonly used antibiotics, including phenicols, quinolones, lincosamides, macrolides, aminoglycosides, and tetracyclines, have been observed on Korean pig farms. Notably, 21 cfr-positive CC398 isolates (four ST541-SCCmec IV MRSA and 17 ST398 MSSA) displaying increased resistance to linezolid were identified in healthy pigs.ConclusionsIn summary, these findings suggest that the multidrug-resistant CC398 S. aureus lineage predominantly colonizes healthy pigs and farm environments in Korea. The emergence of cfr-positive S. aureus at human-animal interfaces presents a significant threat to food safety and public health.

Farmers’ preferences for rice bean production traits in western Kenya

Rice bean (Vigna umbellata) is an important legume for food and nutritional security. However, the level of its cultivation in western Kenya, where there is a serious malnutrition challenge, is still low due to a lack of insights into its attributes. Hence, to bridge this knowledge gap, this study analyzed smallholder farmers' preferences for production traits. We collected data from 204 farmers through a choice experiment (CE) approach in upper and lower midland agro-ecological zones. Subsequently, we used the random parameter logit (RPL) model to analyze the data. Results showed that farmers preferred all attribute levels presented except 61% or more pest resistance. The lower midland farmers preferred compensation of Kenya shillings (Ksh) 34.93 for yields of 9 or more bags per acre; Ksh 52.22 for 61 to 79 maturity days and; Ksh 20.24 for 40% to 60% pest resistance level. In comparison, upper midland farmers preferred compensation of Ksh 66.44 for 6 to 8 bags per acre; Ksh 53.82 for 9 or more bags per acre; no compensation for 50 to 60 maturity days; and Ksh 132.98 for 40% to 60% pest resistance. However, farmers preferred no compensation for intact pods. The observed differences in farmers’ preferences for rice bean attributes are explained by heterogeneity in the agroecological conditions, farmers’ socio-economic characteristics, and risk perceptions. The findings should inform targeted extension and breeding programs that fit farmers’ diverse environments and resource endowments.

The combination of FLCWK with 5-FU inhibits colon cancer and multidrug resistance by activating PXR to suppress the IL-6/STAT3 pathway.

5-fluorouracil (5-FU) is a preferred chemotherapeutic agent for the treatment of colon cancer. Nonetheless, its clinical effectiveness is frequently hampered by suboptimal therapeutic outcomes and the emergence of drug resistance. Therefore, there exists a pressing demand for novel therapeutic agents to circumvent chemoresistance. The pregnane X receptor (PXR) exerts a pivotal regulatory influence on the proliferation, invasion, and chemoresistance mechanisms in colon cancer. Activation of PXR drives up the transcription of the multidrug resistance gene (MDR1), thus prompting the expression of P-glycoprotein (P-gp) responsible for conferring tumour resistance. This study scrutinized the potential of Fengliao Changweikang (FLCWK) in augmenting the efficacy of 5-FU in the management of colon cancer. To this end, we engineered colon cancer cells with varied levels of PXR expression via lentiviral transfection, subsequently validating the findings in nude mice. By means of MTT assays, flow cytometry apoptosis analysis, Western blotting and immunofluorescence, we probed into the prospective impacts of FLCWK and 5-FU on cellular viability and resistance. Our results revealed that while upregulation of PXR amplified the therapeutic benefits in colon cancer treatment, it concurrently heightened resistance levels. FLCWK demonstrated a capacity to reduce P-gp expression, with the combined administration of FLCWK and 5-FU effectively reversing resistance mechanisms. Furthermore, activation of PXR was found to impede the IL-6/STAT3 signalling pathway. In an effort to mimic the development of colon cancer, we established an azomethane oxide (AOM)/ dextran sodium sulfate (DSS) mouse model, showing that FLCWK bolstered the inhibitory effects of 5-FU, impeding the progression of colon cancer. In summation, our findings point towards the potential of FLCWK in the treatment of colon cancer, particularly in strengthening the therapeutic efficacy of 5-FU in the prevention and control of the disease.

Mercury-tolerant metalophiles: A bio tool for remediation of mercury (Hg) affected Environs

Due to their low solubility, carcinogenic and mutagenic effects, heavy metals are of critical concern to humans and the environment. Mercury (Hg) is one of the rarest and least concentrated elements in the world, but it is ranked third in terms of toxicity. The present investigation evaluates the response and tolerance limit of bacteria isolated from the saffron soil of the Kashmir Valley to various mercury concentrations (50 ppm to 400 ppm). The minimum inhibitory concentration (MIC) was calculated after 24hours by measuring the optical density. Isolated bacteria have been characterized using two efficient methods, i.e. 16S rRNA gene sequence and MALDI-TOF MS. A total of 72 isolates were investigated for the mercury tolerance and among them, only 8 isolates (Staphylococcus equorum, Leclercia adecarboxylata, Staphylococcus warneri, Klebsiella pneumoniae, Serratia plymuthica, Bacillus megaterium, Pseudomonas putida and Bacillus safensis) were found tolerant to mercury with varying MIC. In comparison, Pseudomonas putida has been found to have the maximum resistance (400 ppm) for mercury and S. plymuthica and L. adecarboxylate had the lowest resistance level (200 ppm). The sequestration potential results revealed that P. putida executed the highest sequestration potential (73%) while K. pneumoniae showed the lowest sequestration potential (51.63%). Thus mercury tolerance capacity of these species may be utilised for detoxification and removal of mercury from polluted sites, providing an eco-friendly technique for bioremediation of mercury-affected environments.

Water Use Efficiency Characteristics and Their Contributions to Yield in Diverse Sugarcane Genotypes with Varying Drought Resistance Levels Under Different Field Irrigation Conditions

Drought is the major abiotic constraint affecting sugarcane productivity and quality worldwide. This obstacle may be alleviated through sugarcane genotypes demonstrating good water use efficiency (WUE) performance. This study aims to investigate the WUE characteristics of various sugarcane genotypes under different soil water availability levels. Plant and ratoon field experiments were conducted using a split-plot randomized complete block design with three replications. The main plots were assigned three types of irrigation: (1) rainfed conditions (RF), (2) field capacity conditions (FC), and (3) half-available water (½ AW). The subplots consisted of six sugarcane genotypes with varying levels of drought resistance, i.e., KK3, UT13, Kps01-12, KKU99-03, KKU99-02, and UT12. Data on yield, stalk numbers, stalk diameter, height, and WUE were collected throughout the crop cycle for both plant and ratoon crops. For the plant crop, the net photosynthesis rate, transpiration rate, stomatal conductance, and leaf area index (LAI) were recorded during the crop period. In both plant and ratoon crops, the WUE in the RF treatment was lower than in the FC and ½ AW treatments during the drought stress period 4 months after planting (MAP). In the recovery phase, the WUE in the ½ AW treatment fell between the FC and RF treatments. The RF treatment exhibited the lowest WUE compared to the other two water regime treatments at the maturity stage. The drought-resistant genotypes KK3 and UT13 maintained high WUE values throughout both the drought and recovery periods and exhibited outstanding LAIs at 4 and 6 MAP. A significant relationship existed between WUE and LAI during these periods. Moreover, WUE was positively correlated with cane yields and yield components, such as stalk weight, shoot diameter, and height, during recovery and tiller number and height during ripening. Therefore, WUE and LAI are efficient parameters for supporting and maintaining growth and yield during water deficit and recovery phases under rainfed conditions.