scholarly journals Molecular characterisation of Mycoplasma gallisepticum isolates from Iran in the period 2012–2017

2019 ◽  
Vol 67 (3) ◽  
pp. 347-359 ◽  
Author(s):  
Hassan Norouzian ◽  
Ghasem Farjanikish ◽  
Hossein Hosseini
Keyword(s):  
Egg Production ◽  
Mycoplasma Gallisepticum ◽  
Feed Consumption ◽  
Upper Respiratory Tract ◽  
Nucleotide Difference ◽  
Genetic Characteristics ◽  
Backyard Poultry ◽  
Amino Acid Insertion ◽  
Upper Respiratory ◽  
Backyard Flocks

Mycoplasma gallisepticum (MG) causes chronic non-fatal diseases in the poultry industry with a remarkable decrease in feed consumption, egg production and other production indices. To study the genetic characteristics of MG isolates in commercial and backyard poultry flocks, 21 positive samples from different regions of Iran were analysed in the period 2012–2017. Typical macroscopic and histopathological lesions of the upper respiratory tract and lungs were found, similar to those reported by other researchers. A 298–361 bp part of the mgc2 gene was sequenced and analysed. Based on the phylogenetic analysis, the Iranian MG isolates fell into four distinct subgroups. The nucleotide difference between subgroups 1 and 4 was remarkable (91.6–94.9%). A 22-amino-acid insertion was present in two of the studied MG isolates, not observed in other vaccine and standard MG strains. The Iranian Veterinary Organisation (IVO) should consider the observed diversity of prevalent MG isolates from both commercial and backyard flocks in designing the strategy for controlling MG. More studies are needed to understand modifications in MG antigenicity and pathogenicity because of the observed genetic variations.

scholarly journals Genetic Characteristics and Clonal Dissemination of β-Lactamase-Negative Ampicillin-Resistant Haemophilus influenzae Strains Isolated from the Upper Respiratory Tract of Patients in Japan

2007 ◽  
Vol 51 (11) ◽  
pp. 3969-3976 ◽  
Author(s):  
Muneki Hotomi ◽  
Keiji Fujihara ◽  
Dewan S. Billal ◽  
Kenji Suzuki ◽  
Tadao Nishimura ◽  
...  
Keyword(s):  
Haemophilus Influenzae ◽  
Upper Respiratory Tract ◽  
Gene Encoding ◽  
Genetic Characteristics ◽  
Group Iii ◽  
Medical Centers ◽  
Group I ◽  
Dna Restriction ◽  
Resistant Strains ◽  
Upper Respiratory

ABSTRACT We evaluated the recent prevalence of antimicrobial-resistant Haemophilus influenzae isolated from the upper respiratory tracts (URT) of patients in Japan. Mutations in the ftsI gene, which encodes penicillin binding protein 3 (PBP3), and the clonal dissemination of the resistant strains were also investigated. A total of 264 H. influenzae isolates were collected from patients with URT infections. According to the criteria of the Clinical and Laboratory Standards Institute for the susceptibility of H. influenzae to ampicillin (AMP), the isolates were distributed as follows: 161 (61.0%) susceptible strains (MIC ≤ 1 μg/ml), 37 (14.0%) intermediately resistant strains (MIC = 2 μg/ml), and 66 (25.0%) resistant strains (MIC ≥ 4 μg/ml). According to PCR-based genotyping, 172 (65.1%) of the isolates had mutations in the ftsI gene and were negative for the β-lactamase (bla) gene. These 172 isolates were thus defined as genetically β-lactamase-negative ampicillin-resistant (gBLNAR) strains. The ftsI mutant group included 98 (37.1%) strains with group I/II mutations in the variable mutated region (group I/II gBLNAR) and 74 (28.0%) strains with group III mutations in the highly mutated region (group III gBLNAR). Eighty-seven (33.0%) of the isolates were genetically β-lactamase-negative ampicillin-susceptible (gBLNAS) strains. The group III gBLNAR strains showed resistance to β-lactams. Only five strains (1.9%) were positive for a bla gene encoding TEM-type β-lactamase. The three clusters consisting of 16 strains found among the 61 BLNAR strains (MIC ≥ 4 μg/ml and without the bla gene) showed identical or closely related DNA restriction fragment patterns. Those isolates were frequently identified among strains with a MIC to AMP of 16 μg/ml. The current study demonstrates the apparent dissemination and spread of a resistant clone of H. influenzae among medical centers in Japan. The gBLNAR strains show a remarkable prevalence among H. influenzae isolates, with the prevalence increasing with time. This fact should be taken into account when treating URT infections.

Allergy of the Upper Respiratory Tract

1970 ◽  
Vol 3 (2) ◽  
pp. 265-276 ◽  
Author(s):  
Jack D. Clemis ◽  
Eugene L. Derlacki
Keyword(s):  
Respiratory Tract ◽  
Upper Respiratory Tract ◽  
Upper Respiratory
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