Mycobacterium tuberculosis isolates belonging to katG gyrA group 2 are associated with clustered cases of tuberculosis in Italian patients

2004 ◽  
Vol 53 (2) ◽  
pp. 155-159 ◽  
Author(s):  
L. Dolzani ◽  
M. Rosato ◽  
B. Sartori ◽  
E. Banfi ◽  
C. Lagatolla ◽  
...  

Fifty-one consecutive isolates of Mycobacterium tuberculosis, collected during a 2-year period in the north-east of Italy, were subjected to IS6110-RFLP analysis to detect the presence of clusters and assigned to one of the three genotypic groups delineated by single nucleotide polymorphisms in the genes katG and gyrA. All the isolates collected from the local population belonged to group 2 or 3, while group 1 isolates were found only in specimens collected from African immigrants. Clustered cases of tuberculosis, which are likely to be related to recently transmitted infection, were found to be significantly associated with katG gyrA group 2. In the local situation, strains belonging to this group may therefore present a higher risk of transmission.

2000 ◽  
Vol 38 (2) ◽  
pp. 669-676 ◽  
Author(s):  
Hanna Soini ◽  
Xi Pan ◽  
Amol Amin ◽  
Edward A. Graviss ◽  
Anees Siddiqui ◽  
...  

Mycobacterium tuberculosis isolates (n= 1,429) from 1,283 patients collected as part of an ongoing population-based tuberculosis epidemiology study in Houston, Texas, were analyzed by spoligotyping and IS6110 profiling. The isolates were also assigned to one of three major genetic groups on the basis of nucleotide polymorphisms located at codons 463 and 95 in the genes (katG and gyrA) encoding catalase-peroxidase and the A subunit of DNA gyrase, respectively. A total of 225 spoligotypes were identified in the 1,429 isolates. There were 54 spoligotypes identified among 713 isolates (n= 623 patients) assigned to 73 IS6110 clusters. In addition, among 716 isolates (n = 660 patients) with unique IS6110 profiles, 200 spoligotypes were identified. No changes were observed either in the IS6110 profile or in the spoligotype for the 281 isolates collected sequentially from 133 patients. Five instances in which isolates with slightly different spoligotypes had the same IS6110 profile were identified, suggesting that in rare cases isolates with different spoligotypes can be clonally related. Spoligotypes correlated extremely well with major genetic group designations. Only three very similar spoligotypes were shared by isolates from genetic groups 2 and 3, and none was shared by group 1 and group 2 organisms or by group 1 and group 3 organisms. All organisms belonging to genetic groups 2 and 3 failed to hybridize with spacer probes 33 to 36. Taken together, the results support the existence of three distinct genetic groups of M. tuberculosis organisms and provide new information about the relationship between IS6110 profiles, spoligotypes, and major genetic groups of M. tuberculosis.


Author(s):  
Saeed Zaker ◽  
Hanie Bagherifard

Background and Aims: Unlike many global efforts to eradicate tuberculosis caused by Mycobacterium, it remains as a life-threatening infection with a worldwide incidence of 1.5 million cases each year. However, due to the lack of information about Mycobacterium tuberculosis characterization, more studies are required to evaluate strain diversity and epidemiology of tuberculosis to improve the therapeutic approaches. This study aimed to genotype the Mycobacterium tuberculosis isolated from suspected patients in Tehran, Iran through 2015-2017.Materials and Methods: In the current study, 30 isolates (sputum, broncho-alveolar lavage and biopsy) were collected from different tuberculosis patients at Massoud Clinical Lab of Tehran from 2015 to 2017. To find the single nucleotide polymorphisms and mutated regions, polymerase chain reaction (PCR) was performed on all the isolates to amplify the katG and gyrA genes. Then, PCR products were sequenced and analyzed.Results: The majority of isolates were assigned to PGG2 (90%), followed by PGG3 (10%) but no isolate belonging to PGG1 was found.Conclusions: Our findings demonstrate a remarkable epidemiological pattern of tuberculosis in Tehran. In group 2, isolates showed a considerably higher frequency compared to isolates in group 3, which is consistent with other findings reported in Iran. However, in contrast to other Iranian studies, no isolated strains were categorized in principal PGG1.


2021 ◽  
Vol 10 (5) ◽  
pp. e2210514440
Author(s):  
Michelle Lemos Vargens ◽  
Margarida Paula Carreira de Sá Prazeres ◽  
Rosiane de Jesus Barros ◽  
Erlin Cely Cotrim Cavalcante ◽  
Analy Castro Lustosa Cavalcante ◽  
...  

In order to determine Maedi-Visna virus (MVV) seroprevalence and risk factors associated with infection in sheep, 445 animals of both sexes and different ages were tested using the Agarose Gel Immunodiffusion technique (IDGA). The animals were divided into two groups: group 1 composed of exhibition animals (n=70) and group 2 composed of animals from properties from the north, east and central mesoregions of the state of Maranhão (n=375). The general prevalence of MVV infection was 2.02%; 1.42% in group 1 and 2.13% in group 2. In the north mesoregion the prevalence was 2.20%, while a total of 40% of the animals living in municipalities for MVV. It was observed that 1.15% of males and 2.23% of females were seropositive (p> 0.20). Regarding breeds, the Dorper (1.66%); Santa Inês (1.67%); White Dorper (33.33%) and Texel (4.34%) were the most affected. This was the only variable among all the risk factors studied that had a significant association in multivariate analysis (p <0.05). MVV infection is present regardless of the purpose of breeding, and the animals are exposed to the same risk of infection. This demonstrates the need to implement public policies for the prevention, control, and eradication of this disease.


Geofluids ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Qin Ge ◽  
Xing Liang ◽  
Menggui Jin ◽  
Jing Li ◽  
Yan Liu

The hydrogeochemical and stable isotope compositions of aquitard porewater samples from three boreholes were investigated to determine the origin, salinization, and hydrochemical evolution of water in the North Jiangsu coastal plain, China. Three porewater groups were identified based on the water-bearing subsystems. The total dissolved solids (TDS) of porewater samples highly varied from 0.03 to 26.1 g/L. Molar Cl/Br ratios and δ18O and δ2H data indicate that the source of Group 1 salinized porewater was the Holocene seawater, whereas Group 3 salinized samples were probably related to the remnant palaeoseawater of the Late Pleistocene. Group 2 samples had low salinity (TDS < 1 g/L) and undetectable Br− concentrations, which were probably recharged during a colder period and without evidence of seawater involvement. The salinized porewater was likely diluted by freshwater, as evidenced by its depleted isotopes and low salinity relative to standard seawater. The ionic ratios and ionic deltas indicate that considerable water-rock interactions (e.g., cation exchange and mineral weathering) also accounted for the hydrochemical constituents of porewaters, and cation exchange seems to be more noticeable at low salinity.


2021 ◽  
Vol 15 (3) ◽  
pp. 15-19
Author(s):  
M. Yu. Krylov ◽  
G. I. Gridneva ◽  
Yu. V. Muravyev

Clinical response to methotrexate (MT) therapy in rheumatoid arthritis (RA) can be predicted on the basis of some single nucleotide polymorphisms (SNPs) of genes, involved in folate metabolism. One of these SNPs is the rs1801394 (A66G) polymorphism of the methionine synthase reductase gene (MTRR). We investigated the association of this polymorphism with the clinical characteristics of RA patients after 6 months of MT therapy. Studies of the relationship between the response to MT therapy and the rs1801394 polymorphism have not been carried out in Russia previously.Objective: to study the possible association of the rs1801394 polymorphism with the clinical characteristics of patients with RA after 6 months of MT therapy.Patients and methods. The study included 60 patients with RA who met the ACR / EULAR criteria (2010) and received≥20 mg MT per week continuously. Based on the EULAR criteria, patients were divided into two groups: group 1 (n=30) with a good (DAS28>1.2) and group 2 (n=30) with an unsatisfactory (DAS28 <1.2) response to MT therapy. Genotyping of the rs1801394 polymorphism was performed by allelic discrimination using real-time polymerase chain reaction.Results and discussion. The frequency distribution of the A66G polymorphism genotypes in both groups was similar, however, in the 2nd group with an unsatisfactory response, there was a tendency towards a higher frequency of the mutant GG genotype (p=0.067). An association of the A66G polymorphism with gender and disease duration was found. In group 1, the AG genotype was more often detected in men than in women (p=0.017). In group 2, the AG genotype was also more common in men (p=0.075). In addition, in this group, carriers of the G allele (genotypes AG and GG) had a longer duration of the disease than carriers of the AA genotype (p=0.003 and p=0.005, respectively).Conclusion. In the present study, the relationship of the studied polymorphism rs1801394 of the MTRR gene with gender and duration of RA disease was established.


2019 ◽  
Vol 63 (7) ◽  
Author(s):  
Marva Seifert ◽  
Edmund Capparelli ◽  
Donald G. Catanzaro ◽  
Timothy C. Rodwell

ABSTRACT Clinical phenotypic fluoroquinolone susceptibility testing of Mycobacterium tuberculosis is currently based on M. tuberculosis growth at a single critical concentration, which provides limited information for a nuanced clinical response. We propose using specific resistance-conferring M. tuberculosis mutations in gyrA together with population pharmacokinetic and pharmacodynamic modeling as a novel tool to better inform fluoroquinolone treatment decisions. We sequenced the gyrA resistance-determining region of 138 clinical M. tuberculosis isolates collected from India, Moldova, Philippines, and South Africa and then determined each strain’s MIC against ofloxacin, moxifloxacin, levofloxacin, and gatifloxacin. Strains with specific gyrA single-nucleotide polymorphisms (SNPs) were grouped into high or low drug-specific resistance categories based on their empirically measured MICs. Published population pharmacokinetic models were then used to explore the pharmacokinetics and pharmacodynamics of each fluoroquinolone relative to the empirical MIC distribution for each resistance category to make predictions about the likelihood of patients achieving defined therapeutic targets. In patients infected with M. tuberculosis isolates containing SNPs associated with a fluoroquinolone-specific low-level increase in MIC, models suggest increased fluoroquinolone dosing improved the probability of achieving therapeutic targets for gatifloxacin and moxifloxacin but not for levofloxacin and ofloxacin. In contrast, among patients with isolates harboring SNPs associated with a high-level increase in MIC, increased dosing of levofloxacin, moxifloxacin, gatifloxacin, or ofloxacin did not meaningfully improve the probability of therapeutic target attainment. We demonstrated that quantifiable fluoroquinolone drug resistance phenotypes could be predicted from rapidly detectable gyrA SNPs and used to support dosing decisions based on the likelihood of patients reaching therapeutic targets. Our findings provide further supporting evidence for the moxifloxacin clinical breakpoint recently established by the World Health Organization.


Antibiotics ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 107 ◽  
Author(s):  
Hein ◽  
Sander ◽  
Giryes ◽  
Reinhardt ◽  
Hoegel ◽  
...  

(1) Background: Genetically based hyperinflammation may play a role in pathogen defense. We here questioned whether alterations in circulating monocytes/macrophages, inflammatory biomarkers and a functional SNP (single nucleotide polymorphisms) of the Interleukin-6 (IL-6) promotor might play a role in patients with persistent, and treatment resistant borreliosis. (2) Methods: Leukocyte subpopulations were studied by flow cytometry; plasma cytokines were determined by a chemiluminescence based ELISA (Immulite®), and genotypes of the IL-6 promotor SNP rs1800795 were determined by pyrosequencing. (3) Results: In a cohort of n = 107 Lyme borreliosis patients, who concomitantly manifested either malignant diseases (group 1), autoimmune disorders (group 2), neurological diseases (group 3), or morbidities caused by multiple other infectious complications (group 4), we found decreased numbers of anti-inflammatory CD163-positive macrophages, elevated concentrations of inflammatory cytokines, and an imbalance of IL-6 promotor SNP rs1800795 genotypes. The most prominently upregulated cytokines were IL-1β, and IL-8. (4) Conclusions: Increased pro-inflammatory phenotypes identified by monocyte/macrophage subtypes and concomitantly increased cytokines appear to be valid to monitor disease activity in patients with persistent Lyme borreliosis. Patterns may vary by additional co-morbidities. In patients with autoimmune diseases, increased frequencies of a heterozygous IL-6 promotor SNP rs1800795 were identified. This functional SNP may guide chronic inflammation, impacting other cytokines to trigger trigger chronicity and therapeutic resistance in Lyme borreliosis.


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