Changes in the rates of antimicrobial resistance among clinical isolates of Pseudomonas aeruginosa between 2002 and 2004 in a tertiary-care teaching hospital in Turkey

Pseudomonas aeruginosa is an important opportunistic pathogen usually resistant to most antimicrobials. We present changes in the resistance pattern of P. aeruginosa to amikacin (AK) and ciprofloxacin (CIP) between January 2002 and June 2004. The physicians of each unit were given information on antibiotic resistance rates of P. aeruginosa isolated from ward patients at regular intervals. The antibiotic resistance of 161 P. aeruginosa isolates isolated from intensive care units (ICUs) and non-ICUs were tested by disk diffusion method, and the results were interpreted according to the guidelines of National Committee for Clinical Laboratory Standards. Thirty-five percent of all the P. aeruginosa isolates were resistant to AK in 2002, 18% in 2003, and 20% in 2004. The CIP resistance rates were 4% in 2002, 26% in 2003, and 20% in 2004. In that period, resistance to AK decreased, whereas resistance to CIP increased. The usage rate of AK in 2002 was 32%, which fell to 26% in 2003 (p < 0.05). This rate increased to 27% in 2004 (p < 0.05). The usage rate of CIP was very low in 2002 (3%). Subsequently, it increased to 8% in 2003 and 2004 (p < 0.05). The changes in resistance rates may have been due to alteration in drug usage policy in our hospital. It is important to provide physicians with information on antibiotic resistance rates at regular intervals to guide therapy for critical P. aeruginosa infections.     

Protein Paucimannosylation Is an Enriched N‐Glycosylation Signature of Human Cancers

While aberrant protein glycosylation is a recognized characteristic of human cancers, advances in glycoanalytics continue to discover new associations between glycoproteins and tumorigenesis. This glycomics‐centric study investigates a possible link between protein paucimannosylation, an under‐studied class of human N‐glycosylation [Man_1‐3GlcNAc₂Fuc_0‐1], and cancer. The paucimannosidic glycans (PMGs) of 34 cancer cell lines and 133 tissue samples spanning 11 cancer types and matching non‐cancerous specimens are profiled from 467 published and unpublished PGC‐LC‐MS/MS N‐glycome datasets collected over a decade. PMGs, particularly Man_2‐3GlcNAc₂Fuc₁, are prominent features of 29 cancer cell lines, but the PMG level varies dramatically across and within the cancer types (1.0–50.2%). Analyses of paired (tumor/non‐tumor) and stage‐stratified tissues demonstrate that PMGs are significantly enriched in tumor tissues from several cancer types including liver cancer (p = 0.0033) and colorectal cancer (p = 0.0017) and is elevated as a result of prostate cancer and chronic lymphocytic leukaemia progression (p < 0.05). Surface expression of paucimannosidic epitopes is demonstrated on human glioblastoma cells using immunofluorescence while biosynthetic involvement of N‐acetyl‐β‐hexosaminidase is indicated by quantitative proteomics. This intriguing association between protein paucimannosylation and human cancers warrants further exploration to detail the biosynthesis, cellular location(s), protein carriers, and functions of paucimannosylation in tumorigenesis and metastasis.     

Evaluation of amino acid profile in serum of patients with Covid-19 for providing a new treatment strategy

BackgroundAmino acids have an important role in metabolism and may affect COVID-19-related outcomes. In our study, the amino acid serum level of hospitalized COVID19 patients was evaluated to determine a new treatment strategy.MethodsThe amino acid profile covering 43 amino acids in 68 subjects, comprising 30 (14 men and 16 women) controls and 38 (16 men and 22 women) COVID-19 patients, were examined. The amino acid profiles of the participants were screened by LC-MS/MS.ResultsCompared with the control group, serum levels of 27 amino acids increased in the patient group. Alpha-aminopimelic acid, sarcosine, and hydroxyproline amino acids were considerably higher in the control group than in the patient group (p<0.0001). There was no notable difference among control group and the case group for 13 amino acids (p≥0.05). A significant positive correlation was seen among the control and the patient groups in the mean amino acid values (r=0.937; p<0.0001).ConclusionsThese results postulated a clear picture on the serum levels of amino acid in the COVID-19 patients. Serum amino acids measured in hospitalized COVID-19 patients can explain the patient''s metabolic status during the disease.     

In vitro and In vivo Effects of Some Fungicides against the Chickpea Blight Pathogen, Ascochyta rabiei

The effects of various fungicides on mycelial growth and spore germination of Ascochyta rabiei were determined by incorporating them into potato dextrose agar and measuring colony diameter and observing colony growth and spore germination at 20 ± 2°C. Eight fungicides prevented spore germination of the pathogen at concentrations of 0.125–2 μg/ml, three hindered mycelial growth at 2–4 μg/ml and seven failed to inhibit mycelial growth even at 128 μg/ml. The reference fungicide for the pathogen, chlorothalonil, stopped conidial germination at low rates but did not prevent mycelial growth at 128 μg/ml. Thirteen fungicides were tested against seed infections of the pathogen, and benomyl + thiram, carbendazim and carbendazim + chlorothalonil seed treatments gave more than 85% inhibition on both vacuum‐infiltrated and naturally infected seeds. Coating the seeds with polymers did not increase the effectiveness of fungicides. Three fungicides; (azoxystrobin, chlorothalonil and mancozeb), gave the highest protection in the field but protection decreased with increased inoculum pressure. Addition of humic acid to fungicide suspensions did not affect their performance.     

Fucosebeta-1-P-Ser is a new type of glycosylation: using antibodies to identify a novel structure in Dictyostelium discoideum and study multiple types of fucosylation during growth and development

Three antibodies that recognize distinct fucose epitopes were used to study fucosylation during growth and development of Dictyostelium discoideum. mAb83.5 is known to recognize an undefined "fucose epitope" on several proteins with serine-rich domains, while mAb CAB4, and a component of anti-horse-radish peroxidase, specifically recognize Fucalpha1,6GlcNAc and Fucalpha1,3GlcNAc residues respectively in the core of N-linked oligosaccharides. We show that mAb 83.5 defines a new type of O-glycosylation. Serine-containing peptides incubated with GDPbeta[3H]Fuc and microsomes formed two fucosylated products. A neutral product accounting for 30% of the label did not react with the antibody, while the rest of the label was incorporated into a charged product which contained all the mAb83.5 reactive material. beta- Elimination of the labeled peptide or endogenous products produced [3H]Fuc-1-P, indicating phosphodiester linkage to serine. Fucbeta-1-P and GDP-betaFuc at 100 microM blocked mAb83.5 binding to endogenous and peptide products, but their alpha-linked anomers did not. Electrospray ionization mass spectra of the neutral and anionic labeled products showed major peaks of mass units corresponding to O-Fuc-Ser peptide and O-Fuc-phospho-Ser peptide, respectively. The activity of Fuc- phosphotransferase exactly paralleled the accumulation of reactive glycans during growth and development. The expressions of N-glycan core Fucalpha1,6GlcNAc and Fucalpha1,3GlcNAc and their respective fucosyl transferase activities were also synchronous, but their developmental regulation differed from one another. Fucalpha1, 6GlcNAc was expressed maximally during growth but declined during development. In contrast core Fucalpha1,3GlcNAc epitopes were expressed almost exclusively during development. These findings provide direct evidence for a novel type of O-phosphofucosylation, demonstrate the existence of an O- fucosyl transferase, and identify two different types of core fucosylation in the N-glycans of Dictyostelium.