Last data update: Dec 02, 2024. (Total: 48272 publications since 2009)
Records 1-7 (of 7 Records) |
Query Trace: Itsko M[original query] |
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Metabolome dynamics during wheat domestication.
Ben-Abu Y , Itsko M . Sci Rep 2022 12 (1) 8532 One of the most important crops worldwide is wheat. Wheat domestication took place about 10,000 years ago. Not only that its wild progenitors have been discovered and phenotypically characterized, but their genomes were also sequenced and compared to modern wheat. While comparative genomics is essential to track genes that contribute to improvement in crop yield, comparative analyses of functional biological end-products, such as metabolites, are still lacking. With the advent of rigorous mass-spectrometry technologies, it is now possible to address that problem on a big-data scale. In attempt to reveal classes of metabolites, which are associated with wheat domestication, we analyzed the metabolomes of wheat kernel samples from various wheat lines. These wheat lines represented subspecies of tetraploid wheat along primary and secondary domestications, including wild emmer, domesticated emmer, landraces durum, and modern durum. We detected that the groups of plant metabolites such as plant-defense metabolites, antioxidants and plant hormones underwent significant changes during wheat domestication. Our data suggest that these metabolites may have contributed to the improvement in the agricultural fitness of wheat. Closer evaluation of specific metabolic pathways may result in the future in genetically-engineered high-yield crops. |
Meningococcal disease in North America: Updates from the Global Meningococcal Initiative.
Asturias EJ , Bai X , Bettinger JA , Borrow R , Castillo DN , Caugant DA , Chacon GC , Dinleyici EC , Aviles GE , Garcia L , Glennie L , Harrison LH , Howie RL , Itsko M , Lucidarme J , Marin JEO , Marjuki H , McNamara LA , Mustapha MM , Robinson JL , Romeu B , Sadarangani M , Sáez-Llorens X , Sáfadi MAP , Stephens DS , Stuart JM , Taha MK , Tsang RSW , Vazquez J , De Wals P . J Infect 2022 85 (6) 611-622 This review summarizes the recent Global Meningococcal Initiative (GMI) regional meeting, which explored meningococcal disease in North America. Invasive meningococcal disease (IMD) cases are documented through both passive and active surveillance networks. IMD appears to be decreasing in many areas, such as the Dominican Republic (2016: 18 cases; 2021: 2 cases) and Panama (2008: 1 case/100,000; 2021: <0.1 cases/100,000); however, there is notable regional and temporal variation. Outbreaks persist in at-risk subpopulations, such as people experiencing homelessness in the US and migrants in Mexico. The recent emergence of β-lactamase-positive and ciprofloxacin-resistant meningococci in the US is a major concern. While vaccination practices vary across North America, vaccine uptake remains relatively high. Monovalent and multivalent conjugate vaccines (which many countries in North America primarily use) can provide herd protection. However, there is no evidence that group B vaccines reduce meningococcal carriage. The coronavirus pandemic illustrates that following public health crises, enhanced surveillance of disease epidemiology and catch-up vaccine schedules is key. Whole genome sequencing is a key epidemiological tool for identifying IMD strain emergence and the evaluation of vaccine strain coverage. The Global Roadmap on Defeating Meningitis by 2030 remains a focus of the GMI. |
Enhancing meningococcal genomic surveillance in the meningitis belt using high-resolution culture-free whole genome sequencing.
Itsko M , Topaz N , Ousmane S , Popoola M , Ouedraogo R , Gamougam K , Sadji AY , Abdul-Karim A , Lascols C , Wang X . J Infect Dis 2022 226 (4) 729-737 Rollout of meningococcal serogroup A conjugate vaccine in Africa started in 2010, aiming to eliminate meningitis outbreaks, in meningitis belt countries. Since then, studies have been conducted, primarily using isolates, to assess the vaccine impact on the distribution of meningococcal strains in the region. Here, we implemented an innovative, culture-free whole genome sequencing approach on almost 400 clinical specimens collected between 2017-2019 from meningococcal meningitis cases in 6 African countries. About 50% of specimens provided high-quality whole genome sequence data for comprehensive molecular profiling of the meningococcal pathogen. Three major clonal complexes were identified: CC11 associated with serogroup W, CC181 associated with serogroup X and CC10217 associated with serogroup C, which continues to rise as a predominant clonal complex in the region. Genomic surveillance for meningococcal meningitis can be significantly improved using culture-free methods to increase data representativeness and monitor changes in epidemiological landscape, especially for countries with low culture rate. |
Neisseria meningitidis serogroup C clonal complex 10217 outbreak in West Kpendjal Prefecture, Togo 2019
Feagins AR , Sadji AY , Topaz N , Itsko M , Halatoko JWA , Dzoka A , Labite J , Kata Y , Gomez S , Kossi K , Assane H , Nikiema-Pessinaba C , Novak R , Marjuki H , Wang X . Microbiol Spectr 2022 10 (2) e0192321 Togo has reported seasonal meningitis outbreaks caused by non-Neisseria meningitidis serogroup A (NmA) pathogens since the introduction of meningococcal serogroup A conjugate vaccine (MACV, MenAfriVac) in 2014. From 2016 to 2017, NmW caused several outbreaks. In early 2019, a NmC outbreak was detected in the Savanes region of Togo and its investigation is described here. Under case-based surveillance, epidemiological and clinical data, and cerebrospinal fluid specimens were collected for every suspected case of meningitis. Specimens were tested for meningitis pathogens using confirmatory microbiological and molecular methods. During epidemic weeks 9 to 15, 199 cases were reported, with 179 specimens being available for testing and 174 specimens (97.2%) were tested by at least one confirmatory method. The NmC was the predominant pathogen confirmed (93.9%), belonging to sequence type (ST)-9367 of clonal complex (CC) 10217. All NmC cases were localized to the West Kpendjal district of the Savanes region with attack rates ranging from 4.1 to 18.8 per 100,000 population and case fatality rates ranging up to 2.2% during weeks 9 to 15. Of the 93 NmC confirmed cases, 63.4% were males and 88.2% were in the 5 to 29 age group. This is the first report of a NmC meningitis outbreak in Togo. The changing epidemiology of bacterial meningitis in the meningitis belt post-MACV highlights the importance of monitoring of emerging strain and country preparedness for outbreaks in the region. IMPORTANCE The recent emergence of an invasive NmC strain in Togo is an example of the changing bacterial meningitis epidemiology in the meningitis belt post-MACV. The current epidemiology includes the regional circulation of various non-NmA serogroups, which emphasizes the need for effective molecular surveillance, laboratory diagnosis, and a multivalent vaccine that is effective against all serogroups in circulation. |
Evaluation of urethrotropic clade meningococcal infection by urine metagenomic shotgun sequencing.
Retchless AC , Itsko M , Bazan JA , Norris Turner A , Hu F , Joseph SJ , Carter A , Brown M , Snyder B , Wang X . J Clin Microbiol 2021 60 (2) Jcm0173221 Background Urethral infections caused by an emerging nongroupable (NG) urethrotropic clade of Neisseria meningitidis (Nm) were first reported in the United States in 2015 (the "U.S. NmNG urethritis clade"). Here we evaluate for the presence of other urethral pathogens in men with U.S. NmNG urethritis clade infection. Methods: We evaluated 129 urine specimens collected from men at a sexual health clinic, including 33 from patients with culture-confirmed or suspected urethral Nm infection and 96 specimens in which nucleic acid amplification test detected Neisseria gonorrhoeae (Ng), Chlamydia trachomatis (Ct), both pathogens, or neither pathogen. Nm was detected first by real-time PCR, followed by metagenomic shotgun sequencing of 91 specimens to identify coinfections. Nm genomes were sequenced following selective whole genome amplification when possible. Results: Metagenomic sequencing detected Nm in 16 of 17 specimens from culture-confirmed Nm cases, with no coinfection by other conventional urethral pathogens. Metagenomic sequencing also detected Nm in three Ct positive specimens, one specimen positive for both Ng and Ct, and nine specimens with negative Ng and Ct results, eight of which had suspected Neisseria infections. Nm from culture-confirmed Nm cases belonged to the U.S. NmNG urethritis clade, while Nm identified in other specimens belonged to multiple clonal complexes. Additional urethral pathogens were predominant in non-Nm specimens, including Ng, Ct, Mycoplasma genitalium, Ureaplasma urealyticum, and herpes simplex virus type-2. Conclusions: Coinfection with other conventional urethral pathogens is rare in men with culture-confirmed U.S. NmNG urethritis clade infection and points to the strong association of this clade with disease. |
Novel type of coagulation equation and its application to DNA repeat expansion process
Itsko M , Ben Abu Y . J Theor Biol 2020 511 110555 DNA molecules containing repetitive motifs are prone to expand in their lengths. Once there appear a head to tail tandem of two identical DNA sequences in the system, they can propagate indefinitely by the mechanism involving cycles of staggered annealing of complementary DNA strands of variable lengths and polymerase mediated filling-in of the generated overhangs. Microgene Polymerization Reaction (MPR) is an experimental model for expansion of short repetitive DNA to longer lengths. The testable kinetic model of (MPR) was formulated and solved numerically by Itsko et al. in Kinetics of Repeat propagation in the Microgene Polymerization Reaction (2009). Here, the simple cases of MPR were solved analytically. It was found that the repeats propagate according to Gumbel probability density function when the distribution of lengths of obtained polymers follows inverted Gumbel probability density function. |
Full Molecular Typing of Neisseria meningitidis Directly from Clinical Specimens for Outbreak Investigation.
Itsko M , Retchless AC , Joseph SJ , Turner AN , Bazan JA , Sadji AY , Ouédraogo-Traoré R , Wang X . J Clin Microbiol 2020 58 (12) Neisseria meningitidis (Nm) is a leading cause of bacterial meningitis and sepsis worldwide and an occasional cause of meningococcal urethritis. When isolates are unavailable for surveillance or outbreak investigations, molecular characterization of pathogens needs to be performed directly from clinical specimens such as cerebrospinal fluid (CSF), blood, or urine. However, genome sequencing of specimens is challenging because of low bacterial and high human DNA abundances. We developed selective whole genome amplification (SWGA), an isothermal multiple displacement amplification-based method, to efficiently enrich, sequence and de novo assemble Nm DNA from clinical specimens with low bacterial loads. SWGA was validated with 12 CSF specimens from invasive meningococcal disease cases and 12 urine specimens from meningococcal urethritis cases. SWGA increased the mean proportion of Nm reads by 2-3 orders of magnitude enabling identification of at least 90% of the 1605 Nm core genome loci for 50% of the specimens. The validated method was used to investigate two meningitis outbreaks recently reported in Togo and Burkina Faso. Twenty-seven specimens with low bacterial load were processed by SWGA before sequencing and 12 of 27 were successfully assembled to obtain the full molecular typing and vaccine antigen profile of the Nm pathogen, therefore enabling thorough characterization of outbreaks. This method is particularly important for enhancing molecular surveillance in regions with low culture rate. SWGA produces enough reads for phylogenetic and allelic analysis with a low cost. More importantly, the procedure can be extended to enrich other important human bacterial pathogens. |
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