scholarly journals Phenotypic properties of R factors ofPseudomonas aeruginosa:R factors transferable only inPseudomonas aeruginosa

1974 ◽  
Vol 23 (3) ◽  
pp. 251-257 ◽  
Author(s):  
P. M. Chandler ◽  
V. Krishnapillai
Keyword(s):  
Drug Resistance ◽  
Shigella Flexneri ◽  
Low Frequency ◽  
Wild Type ◽  
Phenotypic Properties ◽  
Specific Phage ◽  
Group 2 ◽  
R Factors ◽  
Type Strains ◽  
Group 1

SUMMARYA study was made of the R factors from two multiply drug resistant wild type isolates ofPseudomonas aeruginosafrom a Birmingham hospital (Lowburyet al.1969) from which, in contrast to other strains from the same source (Chandler & Krishnapillai, 1974a), drug resistance was not transferable toEscherichia coliK12 orSalmonella typhimurium. Transfer of drug resistance occurred at a low frequency toShigella flexneri, although drug resistance in this species was subsequently non-transferable.InP. aeruginosathere are several features of these two R factors which distinguish them from the group 1 and 2 R factors described previously (Chandler & Krishnapillai, 1974a). Although coding for resistance to neomycin and tetracycline, they did not express this resistance in two strains ofP. aeruginosaexamined, in contrast to the wild type strains they were isolated in.The control of transfer of the two R factors is different to the group 1 and 2 R factors in that derepression of transfer could be demonstrated following physiological treatments or mutagenesis. The R factors of this third group were compatible with the group 2 R factors, but did not repress their pilus synthesis on the basis of R factor specific phage plating.

scholarly journals Phenotypic properties of R factors ofPseudomonas aeruginosa:R factors readily transferable betweenPseudomonasand the Enterobacteriaceae

1974 ◽  
Vol 23 (3) ◽  
pp. 239-250 ◽  
Author(s):  
P. M. Chandler ◽  
V. Krishnapillai
Keyword(s):  
Drug Resistance ◽  
Host Range ◽  
Multiple Drug Resistance ◽  
Resistance Pattern ◽  
R Factor ◽  
Specific Phage ◽  
Drug Resistance Pattern ◽  
Group 2 ◽  
R Factors ◽  
Group 1

SUMMARYR factors have been demonstrated in multiply drug resistant strains of enterobacteria andPseudomonas aeruginosain a Birmingham hospital (Lowburyet al.1969; Ingram, Richmond & Sykes, 1973). A comparative genetic analysis of these R factors has been initiated on the basis of a variety of phenotypic characteristics. This paper describes the properties of R factors derived from strains which could transfer multiple drug resistance to the recipient speciesP. aeruginosa, Escherichia coli, Shigella flexneriandSalmonella typhimurium. Two types of R factor could be recognized phenotypically. The single group 1 R factor, R18–1 which is probably the same as RPl-1 (Ingramet al.1972) was different to the group 2 R factors in many respects, including host range, R factor-specific phage plating, cellular location, drug resistance pattern, and stability. The group 2 R factors were found to be very similar to RPl (Grinstedet al.1972) and R1822 (Olsen & Shipley, 1973) with respect to their wide host range, plating of a sex specific phage, extrachromosomal location, and drug resistance pattern. Compatibility was shown between the group 1 R factor and a group 2 R factor, providing additional evidence for significant genetic differences.

CLINICAL AND LABORATORY PECULIARITIES OF WHOOPING COUGH IN CHILDREN OF DIFFERENT AGE GROUPS

2020 ◽  
Vol 99 (6) ◽  
pp. 98-104
Author(s):  
I.V. Babachenko ◽  
◽  
Y.V. Nesterova ◽  
N.V. Skripchenko ◽  
◽  
...  
Keyword(s):  
Whooping Cough ◽  
Severe Disease ◽  
Respiratory Rhythm ◽  
Age Groups ◽  
Low Frequency ◽  
Pertussis Infection ◽  
Group 2 ◽  
Sick Children ◽  
Hematological Changes ◽  
Group 1

Objective of the research: to present the clinical and laboratory peculiarities of modern whooping cough in hospitalized children of different ages. Materials and methods: сlinical and laboratory characteristics of whooping cough were analyzed in 88 hospitalized sick children aged 1 month to 18 years in groups of children: group 1 – children under 1 year old; group 2 – children 1–6 years old; group 3 – children 7–17 years old. DNA of causative agents of pertussis infection was isolated by PCR in nasopharyngeal swabs using a commercial kit AmpliSens®Bordetella multi-FL (Moscow). Results: children of group 1 in 90% (n=43) of cases were not vaccinated against whooping cough, severe forms were recorded in 17% (n=8) of children of the 1st year of life, and in 15% (n=7) – due to respiratory rhythm disturbances. The diagnosis was confirmed by PCR in 94% (n=45) of children, leukocytosis with lymphocytosis was detected in 81,5% (n=101). Along with hematological changes typical for whooping cough, 79% (n=38) of patients in the first year of life had thrombocytosis (>400×109/l), which was most pronounced in severe disease course 511,5 [425; 568,5]×109/l vs 421 [347; 505,5]×109/l; p<0,05, which has no tendency to decrease throughout the entire observation period and correlates with the level of leukocytes (rs=0,69; p<0,001). Patients over 7 years old in 88% (n=21) of cases were vaccinated against whooping cough, but 79% (n=27) hemograms had no characteristic changes, which, along with a low frequency of confirmation of the diagnosis by PCR 22% (n=4), made it difficult to diagnose whooping cough. Conclusion: children over 7 years of age may not have characteristic hematological changes and PCR diagnostics are insufficiently effective, which contributes to the spread of whooping cough in family foci.

IMMU-25. SYNERGY BETWEEN TMZ AND INDIVIDUALIZED MULTIMODAL IMMUNOTHERAPY TO IMPROVE OS OF IDH1 WILD TYPE MGMT PROMOTOR UNMETHYLATED GBM PATIENTS

2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi97-vi97
Author(s):  
Stefaan Van Gool ◽  
Jennifer Makalowski ◽  
Volker Schirrmacher ◽  
Wilfried Stuecker
Keyword(s):  
Local Therapy ◽  
Extent Of Resection ◽  
Wild Type ◽  
Advanced Therapy Medicinal Product ◽  
Icd Therapy ◽  
Complementary Medicines ◽  
Relevant Effect ◽  
Advanced Therapy ◽  
Group 2 ◽  
Group 1

Abstract The prognosis of IDH1 wild type MGMT promotor unmethylated (MGMT-p-UM) GBM patients remains poor. Addition of TMZ to radiotherapy shifted the median OS from 11.8 to 12.6 months (Stupp, Lancet Oncol 2019). We retrospectively analysed the value of individualized multimodal immunotherapy (IMI) to improve OS in these patients. Adults with first event of IDH1wt GBM and documented status of MGMT-p-UM, and treated with IMI in the period June 2015 till July 2020, were selected. IMI consisted of 1/ immunogenic cell death (ICD) therapy (NDV injections + modulated electrohyperthermia), 2/ active specific immunotherapy with autologous mature dendritic cells loaded with tumor lysate or ICD therapy-induced serum-derived antigenic extracellular microvesicles and apoptotic bodies (IO-Vac® is an approved advanced therapy medicinal product since 27/05/2015), 3/ modulatory immunotherapy adapted to the patient, and 4/ complementary medicines. Twenty-eight patients (11f, 17m) had a median age of 48y (range 18-69) and a KPI of 90 (50-100). Extent of resection was complete (11), &lt; complete (9) or not documented (8). Seven patients were treated with surgery/radio(chemo)therapy and subsequent IMI (Group-1); 21 patients were treated with radiochemotherapy followed by maintenance TMZ + ICD therapy, followed by DC vaccines (Group-2). Both groups received further maintenance ICD therapy. Age, KPI and extent of resection were not different amongst both groups. PFS was not assessed because of challenges about pseudoprogression. The median OS of group-1 patients was 11m (2y OS: 0%). Surprisingly the median OS of group-2 patients was 18m with 2y OS of 17% (CI95%: +31, -15), which was significantly (Log-rank: p = 0.027) different from group-1. The data suggest that addition of IMI after local therapy on its own has no relevant effect on OS in IDH1 wild type MGMT-p-UM GBM patients, similar to maintenance TMZ. However, the combination of both TMZ + IMI significantly improves median OS.

scholarly journals Bacteriophage use in the focus of hospital-acquired shigellosis

2017 ◽  
Vol 98 (6) ◽  
pp. 917-921
Author(s):  
E S Kurakin
Keyword(s):  
Infection Prevention ◽  
Clinical Effect ◽  
Shigella Flexneri ◽  
Clinical Effectiveness ◽  
Antibacterial Treatment ◽  
Clinical Recovery ◽  
Study Evaluation ◽  
Group 2 ◽  
Hospital Acquired ◽  
Group 1

Aim. Evaluation of epidemiologic effectiveness of polyvalent dysentery bacteriophage use for management of infection outbreak caused by Shigella flexneri. Methods. Investigation was performed in Tula psychoneurological hospital where the persistent focus of shigellosis was formed by Sh. flexneri 2a. As part of the study, evaluation of efficacy of antibacterial treatment (ciprofloxacin 250 mg per day for 7 days - group 1) was performed by evaluating duration of bacterial excretion in 18 patients with mild, 21 with moderate and 2 with severe Shigella infection. At the same time efficacy of Shigella bacteriophage (group 2) was assessed during treatment of 19 patients with mild and 17 with moderate form of the infection. Prevention of hospital-acquired shigellosis was provided for all patients in the departments where the infection was diagnosed. In this case bacteriophage was administered as following: first 5 days - 2 pills of bacteriophage 4 times a day, then 2 pills once a day during the whole period of hospitalization. This scheme was administered also to all patients newly admitted to the involved departments from day 1 of hospital stay. Results. Treatment with antibiotics led to fast and full recovery not in all cases. Insufficient clinical effect (persistence of disease signs and bacterial excretion for more than 7 days) in the treatment of mild, moderate and severe forms of Shigella infection was 16.7, 61.9 and 50.0%, respectively. High clinical effectiveness was noted in the treatment of patients with the use of Shigella bacteriophage. Ratio of insufficient clinical recovery from mild and moderate forms of the disease was 5.3 and 17.6%, respectively. In the course of anti-epidemiological measures aimed at localization and elimination of the focus, about 1000 patients were exposed to mentioned regimen of prevention. No patients had manifested infection or bacterial excretion registered. Conclusion. The study confirmed clinical and epidemiological effectiveness of polyvalent dysentery bacteriophage use for management of outbreak caused by Sh. flexneri 2a.

scholarly journals The Role of Risk Factors in the Development of Tuberculosis in Children Exposed to Rifampicin Resistant Tuberculosis

2021 ◽  
Vol 99 (7) ◽  
pp. 18-25
Author(s):  
N. A. Nikiforenko ◽  
M. E. Lozovskaya ◽  
G. А. Novik ◽  
А. V. Derevyanko ◽  
N. V. Kochmarev
Keyword(s):  
Risk Factors ◽  
Drug Resistance ◽  
Retrospective Study ◽  
Bcg Vaccination ◽  
Resistant Tuberculosis ◽  
Group 2 ◽  
Tuberculosis In Children ◽  
Index Cases ◽  
Group 1

The objective: to identify factors of a higher risk to develop tuberculosis in children exposed to tuberculosis cases resistant or sensitive to rifampicin.Subjects 161 children under 6 years old exposed to tuberculosis in their families were enrolled in the retrospective study. The children were divided into 2 groups: Group 1 (n = 92) – children free of TB; Group 2 (n = 69) – children ill with TB. In each group, two subgroups were identified: those with index cases susceptible to rifampicin (RS) 1A (n = 40) and 2A (n = 43) and those with index cases resistant to rifampicin (RR) 1Б (n = 52) and 2Б (n = 26).Results. Exposure to isoniazid resistant tuberculosis increases the risk of TB in the child by 12 times, on the opposite, drug resistance to rifampicin provides no impact on the risk to develop tuberculosis. If the child is exposed to 2 cases of tuberculosis and more, the risk to develop tuberculosis increases by 2-14 times. BCG vaccination of the child exposed to tuberculosis reduces the risk to develop tuberculosis by 2-13 times.

NUDT15 genetic variants are related to thiopurine-induced neutropenia in Thai children with acute lymphoblastic leukemia

2020 ◽  
Vol 21 (6) ◽  
pp. 403-410
Author(s):  
Apichaya Puangpetch ◽  
Rawiporn Tiyasirichokchai ◽  
Samart Pakakasama ◽  
Supaporn Wiwattanakul ◽  
Usanarat Anurathapan ◽  
...  
Keyword(s):  
Acute Lymphoblastic Leukemia ◽  
Maintenance Therapy ◽  
Therapy Group ◽  
Lymphoblastic Leukemia ◽  
Wild Type ◽  
Homozygous Variant ◽  
Heterozygous Variant ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

Aim: 6-Mercaptopurine (6MP) is key to the treatment of acute lymphoblastic leukemia (ALL) as part of maintenance therapy. NUDT15 was identified as a novel thiopurine regulator conferring 6MP sensitivity. The aim of this study was to evaluate the influence of NUDT15 variants on 6MP-induced neutropenia in Thai children with ALL. Materials & methodology: Genotyping of NUDT15 (c.415C>T; rs116855232) and c.36_37insGGAGTC; rs554405994) was performed by Sanger sequencing in 100 patients with ALL. Patients were classified into wild-type (group 1), heterozygous variant (group 2) and homozygous variant (group 3). Clinical and laboratory features during the first 6 months of maintenance therapy were investigated. Therapy-induced neutropenia was observed in 31 patients during the weeks 1–8 (early myelotoxicity), while therapy-induced neutropenia was observed in 47 patients during the weeks 9–24 (late myelotoxicity). Results: There were 85 wild-type patients, 14 heterozygous variant patients and one homozygous variant patient. NUDT15 variants were associated with neutropenia as compared with wild-type (odds ratio: 17.862; 95% CI: 4.198–75.992, padj = 9.5 × 10-5). Multivariate analysis showed that the low-risk group was associated with neutropenia (p = 0.014) in the first 8 weeks of 6MP therapy. Group 2 and group 3 patients had significantly lower absolute neutrophil counts compared with group 1. The adjusted dose during the first 6 months of maintenance therapy with NUDT15 genotype group 1, 2 and 3 were 50, 36.6 and 12.5 mg/m2/day, respectively. Conclusion: Taken together, our results indicate NUDT15 variants may cause neutropenia, and the 6MP dosage should be considered in patients according to the NUDT15 variants to inform personalized 6MP therapy.

scholarly journals Systematic truncations of chromosome 4 and their responses to antifungals in Candida albicans

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Wasim Uddin ◽  
Darshan Dhabalia ◽  
S. M. Udaya Prakash ◽  
M. Anaul Kabir
Keyword(s):  
Drug Resistance ◽  
Candida Albicans ◽  
Resistant Mutant ◽  
Wild Type ◽  
Human Fungal Pathogen ◽  
Zones Of Inhibition ◽  
Life Threatening ◽  
Fluconazole Resistant ◽  
Diffusion Assay ◽  
Type Strains

Abstract Background Candida albicans is an opportunistic human fungal pathogen responsible for superficial and systemic life-threatening infections. Treating these infections is challenging as many clinical isolates show increased drug resistance to antifungals. Chromosome (Chr) 4 monosomy was implicated in a fluconazole-resistant mutant. However, exposure to fluconazole adversely affects Candida cells and can generate numerous mutations. Hence, the present study aimed to truncate Chr4 and challenge the generated Candida strains to antifungals and evaluate their role in drug response. Results Herein, Chr4 was truncated in C. albicans using the telomere-mediated chromosomal truncation method. The resulting eight Candida strains carrying one truncated homolog of Chr4 were tested for response to multiple antifungals. The minimal inhibitory concentration (MIC) for these strains was determined against three classes of antifungals. The MIC values against fluconazole, amphotericin B, and caspofungin were closer to that of the wild type strain. Microdilution assay against fluconazole showed that the mutants and wild type strains had similar sensitivity to fluconazole. The disc diffusion assay against five azoles and two polyenes revealed that the zones of inhibition for all the eight strains were similar to those of the wild type. Thus, none of the generated strains showed any significant resistance to the tested antifungals. However, spot assay exhibited a reasonably high tolerance of a few generated strains with increasing concentrations of fluconazole. Conclusion This analysis suggested that Chr4 aneuploidy might not underlie drug resistance but rather drug tolerance in Candida albicans.

scholarly journals Description of Shewanella glacialipiscicola sp. nov. and Shewanella algidipiscicola sp. nov., isolated from marine fish of the Danish Baltic Sea, and proposal that Shewanella affinis is a later heterotypic synonym of Shewanella colwelliana

2007 ◽  
Vol 57 (2) ◽  
pp. 347-352 ◽  
Author(s):  
Masataka Satomi ◽  
Birte Fonnesbech Vogel ◽  
Kasthuri Venkateswaran ◽  
Lone Gram
Keyword(s):  
Dna Hybridization ◽  
Type Strain ◽  
Gene Sequence ◽  
Novel Species ◽  
Sequence Similarity ◽  
Rrna Gene ◽  
Rrna Gene Sequence ◽  
Group 2 ◽  
Type Strains ◽  
Group 1

Two novel species belonging to the genus Shewanella are described on the basis of a polyphasic taxonomic approach. A total of 40 strains of Gram-negative, psychrotolerant, H2S-producing bacteria were isolated from marine fish (cod and plaice) caught in the Baltic Sea off Denmark. Strains belonging to group 1 (seven strains) were a lactate-assimilating variant of Shewanella morhuae with a G+C content of 44 mol%. The strains of group 2 (33 strains) utilized lactate, N-acetylglucosamine and malate but did not produce DNase or ornithine decarboxylase. Their G+C content was 47 mol%. Phylogenetic analysis of the 16S rRNA gene sequence data placed the two novel species within the genus Shewanella. Group 1 showed greatest sequence similarity with S. morhuae ATCC BAA-1205T (99.9 %). However, gyrB gene sequence analysis and DNA–DNA hybridization differentiated these isolates from S. morhuae, with 95.6 % sequence similarity and less than 57 % DNA relatedness, respectively. Group 2 strains shared more than 99 % 16S rRNA gene sequence similarity with the type strains of Shewanella colwelliana and Shewanella affinis, but gyrB sequence similarity (~85 %) and the results of DNA hybridization (~28 %) indicated that the new isolates represented a novel species. Furthermore, when compared to each other, the type strains of S. colwelliana and S. affinis had almost identical gyrB sequences and significantly high DNA reassociation values (76–83 %), indicating that they belonged to the same species. Based on the conclusions of this study, we propose the novel species Shewanella glacialipiscicola sp. nov. (type strain T147T=LMG 23744T=NBRC 102030T) for group 1 strains and Shewanella algidipiscicola sp. nov. (type strain S13T=LMG 23746T=NBRC 102032T) for group 2 strains, and we propose that Shewanella affinis as a later heterotypic synonym of Shewanella colwelliana.

scholarly journals Sexual Recombination in Gibberella zeae

1999 ◽  
Vol 89 (2) ◽  
pp. 182-188 ◽  
Author(s):  
Robert L. Bowden ◽  
John F. Leslie
Keyword(s):  
The United States ◽  
Vegetative Compatibility ◽  
Gibberella Zeae ◽  
Rapid Testing ◽  
Wild Type ◽  
Vegetative Compatibility Groups ◽  
Nit Mutants ◽  
Sexual Recombination ◽  
Group 2 ◽  
Group 1

We developed a method for inducing sexual outcrosses in the homothallic Ascomycete fungus Gibberella zeae (anamorph: Fusarium graminearum). Strains were marked with different nitrate nonutilizing (nit) mutations, and vegetative compatibility groups served as additional markers in some crosses. Strains with complementary nit mutations were cocultured on carrot agar plates. Ascospores from individual perithecia were plated on a minimal medium (MM) containing nitrate as the sole nitrogen source. Crosses between different nit mutants segregated in expected ratios (3:1 nit-:nit+) from heterozygous perithecia. Analysis of vegetative compatibility groups of progeny of two crosses indicated two and three vegetative incompatibility (vic) genes segregating, respectively. For rapid testing of sexual recombination between nit mutants, perithecia were inverted over MM to deposit actively discharged ascospores. Development of proto-trophic wild-type colonies was taken as evidence of sexual recombination. Strains of G. zeae group 2 from Japan, Nepal, and South Africa, and from Indiana, Kansas, and Ohio in the United States were sexually interfertile. Four group 1 strains were not interfertile among themselves or with seven group 2 strains. Attempts to cross G. zeae with representatives of F. acuminatum, F. avenaceum, F. culmorum, F. crookwellense, F. oxysporum, and three mating populations of G. fujikuroi were not successful.

scholarly journals Amylose starch with no detectable branching developed through DNA-free CRISPR-Cas9 mediated mutagenesis of two starch branching enzymes in potato

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xue Zhao ◽  
Shishanthi Jayarathna ◽  
Helle Turesson ◽  
Ann-Sofie Fält ◽  
Gustav Nestor ◽  
...  
Keyword(s):  
Genome Editing ◽  
Crystalline Structure ◽  
Mutation Frequency ◽  
Branching Enzyme ◽  
Wild Type ◽  
Branching Enzymes ◽  
Group 3 ◽  
Group 2 ◽  
A Chain ◽  
Group 1

AbstractDNA-free genome editing was used to induce mutations in one or two branching enzyme genes (Sbe) in tetraploid potato to develop starch with an increased amylose ratio and elongated amylopectin chains. By using ribonucleoprotein (RNP) transfection of potato protoplasts, a mutation frequency up to 72% was achieved. The large variation of mutations was grouped as follows: Group 1 lines with all alleles of Sbe1 mutated, Group 2 lines with all alleles of Sbe1 as well as two to three alleles of Sbe2 mutated and Group 3 lines having all alleles of both genes mutated. Starch from lines in Group 3 was found to be essentially free of amylopectin with no detectable branching and a chain length (CL) distribution where not only the major amylopectin fraction but also the shortest amylose chains were lost. Surprisingly, the starch still formed granules in a low-ordered crystalline structure. Starch from lines of Group 2 had an increased CL with a higher proportion of intermediate-sized chains, an altered granule phenotype but a crystalline structure in the granules similar to wild-type starch. Minor changes in CL could also be detected for the Group 1 starches when studied at a higher resolution.

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