scholarly journals Directional Gene Movement from Human-Pathogenic to Commensal-Like Streptococci

2001 ◽  
Vol 69 (8) ◽  
pp. 4858-4869 ◽  
Author(s):  
Awdhesh Kalia ◽  
Mark C. Enright ◽  
Brian G. Spratt ◽  
Debra E. Bessen

ABSTRACT Group A streptococci (GAS) are highly pathogenic for humans, and their closest genetic relatives, group C and G streptococci (GCS and GGS, respectively), are generally regarded as commensals, although they can be found in association with human disease. As part of an effort to better understand the evolution of virulence, the phylogenetic relationships between GAS, GCS, and GGS were examined. The nucleotide sequence was determined for an internal portion of seven housekeeping (neutral) loci among >200 isolates of GAS and 34 isolates of GCS or GGS obtained from human subjects. Genotypic analysis failed to show support for the separation of GCS and GGS into two distinct populations. Unlike GAS, there was poor concordance betweenemm type and genetic relatedness among GCS and GGS. All housekeeping genes within GAS displayed relatively low levels of sequence diversity. In contrast, individual GCS and GGS strains had mosaic genomes, containing alleles at some loci that were similar or identical to GAS alleles, whereas the alleles at other loci were about 10 to 30% diverged. The data provide evidence for a history of recent interspecies transfer of neutral genes that exhibits a strong net directionality from GAS donors to GCS and GGS recipients. A model for the evolution of GAS and of GCS and GGS is described.

1991 ◽  
Vol 105 (6) ◽  
pp. 439-441 ◽  
Author(s):  
A. Stjernquist-Desatnik ◽  
K. Prellner ◽  
C. Schalén

AbstractOne hundred and twenty-six patients who underwent tonsillectomy because of recurrent acute tonsillitis, tonsillar hypertrophy or sleep apnoea were evaluated by tonsillar core culturing. The sleep apnoea patients served as controls, since none of them had tonsillar hypertrophy at ENT examination or any history of recurrent acute tonsillitis, and thus their tonsillar core flora could be regarded as normal.The isolation rate ofH. influenzaewas much lower among sleep apnoea controls (2.7 per cent) than among either the patients with recurrent acute tonsillitis (20.3 per cent) or those with tonsillar hypertrophy (36.7 per cent) (p<0.05), as was that of group A streptococci, 5.4 per centversus16.9 and 20 per cent, respectively (though the latter differences were not statistically significant). The isolation frequencies ofB. catarrhalis, pneumococci, group C and G streptococci did not differ between the three groups.The high tonsillar core recovery rates ofH. influenzaeand group A streptococci both in patients with recurrent acute tonsillitis and in those with tonsillar hypertrophy, as compared with normal controls, suggests the possible involvement of these bacteria in both conditions.


2000 ◽  
Vol 125 (2) ◽  
pp. 299-301 ◽  
Author(s):  
S. POURNARAS ◽  
A. EFSTRATIOU ◽  
J. DOUBOYAS ◽  
R. C. GEORGE ◽  
A. TSAKRIS

Twenty-six isolates of the newly designated M90 serotype group A Streptococcus (GAS) from a large food-borne outbreak of pharyngitis in Greece and six M90 sporadic isolates from UK, were typed by pulsed-field gel electrophoresis (PFGE). Twenty-four outbreak isolates were identical and two closely related. The Greek isolates were possibly related with one UK isolate, while other sporadic isolates exhibited distinct PFGE profiles from the former isolates.


2000 ◽  
Vol 68 (12) ◽  
pp. 7132-7136 ◽  
Author(s):  
Kevin F. Jones ◽  
Stephen S. Whitehead ◽  
Madeleine W. Cunningham ◽  
Vincent A. Fischetti

ABSTRACT Archived sera (collected in 1946) from acute rheumatic fever (ARF) and untreated scarlet fever and/or pharyngitis patients were reacted with streptococcal M protein, cardiac myosin, and cardiac tropomyosin. Except for very low levels to tropomyosin, antibodies to other antigens were not elevated in the sera of ARF patients relative to those of non-ARF patients, even though there was roughly equivalent exposure to group A streptococci. This suggests that antibodies to these molecules may not play a central role in the induction of ARF.


2006 ◽  
Vol 44 (6) ◽  
pp. 2160-2166 ◽  
Author(s):  
V. Sakota ◽  
A. M. Fry ◽  
T. M. Lietman ◽  
R. R. Facklam ◽  
Z. Li ◽  
...  

1994 ◽  
Vol 71 (01) ◽  
pp. 129-133 ◽  
Author(s):  
P J Declerck ◽  
S Vanderschueren ◽  
J Billiet ◽  
H Moreau ◽  
D Collen

SummaryStreptokinase (SK) is a routinely used thrombolytic agent but it is immunogenic and allergenic; staphylokinase (STA) is a potential alternative agent which is under early clinical evaluation. The comparative prevalence of antibodies against recombinant STA (STAR) and against SK was studied in healthy subjects and their induction with intravenous administration in small groups of patients.Enzyme-linked immunosorbent assays, using microtiter plates coated with STAR or SK and calibration with affinospecific human antibodies, revealed 2.1 to 65 μg/ml (median 11 μg/ml) anti-STAR antibodies and 0.9 to 370 μg/ml (median 18 μg/ml) anti-SK antibodies (p <0.001 vs anti-STAR antibodies) in plasma from 100 blood donors, with corresponding values of 0.6 to 100 μg/ml (median 7.1 μg/ml) and 0.4 to 120 μg/ml (median 7.3 μg/ml), respectively, in 104 patients with angina pectoris. Three out of 17 patients with Staphylococcus aureus bacteremia had significantly increased anti-STAR antibody levels (150, 75 and 75 μg/ml), and STAR neutralizing activities (2.2, 3.6 and 4.1 μg STAR neutralized per ml plasma, respectively). In 6 patients with acute myocardial infarction, given 10 mg STAR intravenously over 30 min, median anti-STAR antibody levels were 3.5 μg/ml at baseline, 2.9 μg/ml at 6 to 8 days and 1.2 μg/ml at 2 to 9 weeks, with median corresponding titers of STAR neutralizing activity at 2 to 9 weeks of 42 μg/ml plasma. Conversely, in 5 patients treated with 1,500,000 units SK over 60 min, median anti-SK antibodies increased from 2.9 μg/ml at baseline to 360 μg/ml at 5 to 10 days, with corresponding median SK neutralizing activities of 13 μg/ml. Antibodies against STAR did not cross-react with SK and vice versa.Plasma from human subjects contains low levels of circulating antibodies against recombinant staphylokinase, and intravenous administration of this compound boosts antibody titers. These antibodies do however not cross-react with streptokinase, whereby the use of these two immunogenic thrombolytic agents would not be mutually exclusive.


2018 ◽  
Vol 52 (1-4) ◽  
pp. 22-30
Author(s):  
A K Paul ◽  
S M T Rahman

Hormonal treatment of cows at the coastal region of Barisal district of Bangladesh was performed to assess the improvement of pregnancy rate. A total of 100 cows and heifers with irregular history of cyclicity were selected randomly and divided into five treatment groups. The groups were A (treated with anthelmintic), B (treated with anthelmintic, vitamin ADE and multivitamin powder), C (treated with PGF2α), D (treated with GnRH) and E (treated with GnRH and PGF2α). Each group comprised of 20 animals. The age, breed and parity of experimental cows were considered during treatment. In the study, the cows treated with both GnRH and PGF2α (group E) showed significantly (p<0.05) higher estrus (80%) and pregnancy rate (60%) than that of group A, B, C and D. The overall estrus rates of local and crossbred cows were 64% and 70%, respectively and the pregnancy rates were 40 and 52%, respectively. The crossbred cows responded significantly (p<0.05) to hormonal treatment than that of local cows. Parity-2 cows showed higher estrus sign than that of other parities. However, the pregnancy rates were higher significantly (p<0.05) in parity-2 and parity ≥4 cows than that of parity-0, parity-1 and parity-3 cows. The pregnancy rate was also found higher in case of 4 to <5 years old cows than that of 2 to <3, 3 to <4, 5 to <6, and ≥6 years old. It may conclude that the hormonal regimen increases the pregnancy rate as well as decreases the undesired waiting of estrus and conception. Further study with more sample size will reveal the more effective treatment for cows at the coastal areas of Bangladesh.


2018 ◽  
Vol 52 (1-4) ◽  
pp. 22-30
Author(s):  
A K Paul ◽  
S M T Rahman

Hormonal treatment of cows at the coastal region of Barisal district of Bangladesh was performed to assess the improvement of pregnancy rate. A total of 100 cows and heifers with irregular history of cyclicity were selected randomly and divided into five treatment groups. The groups were A (treated with anthelmintic), B (treated with anthelmintic, vitamin ADE and multivitamin powder), C (treated with PGF2α), D (treated with GnRH) and E (treated with GnRH and PGF2α). Each group comprised of 20 animals. The age, breed and parity of experimental cows were considered during treatment. In the study, the cows treated with both GnRH and PGF2α (group E) showed significantly (p<0.05) higher estrus (80%) and pregnancy rate (60%) than that of group A, B, C and D. The overall estrus rates of local and crossbred cows were 64% and 70%, respectively and the pregnancy rates were 40 and 52%, respectively. The crossbred cows responded significantly (p<0.05) to hormonal treatment than that of local cows. Parity-2 cows showed higher estrus sign than that of other parities. However, the pregnancy rates were higher significantly (p<0.05) in parity-2 and parity ≥4 cows than that of parity-0, parity-1 and parity-3 cows. The pregnancy rate was also found higher in case of 4 to <5 years old cows than that of 2 to <3, 3 to <4, 5 to <6, and ≥6 years old. It may conclude that the hormonal regimen increases the pregnancy rate as well as decreases the undesired waiting of estrus and conception. Further study with more sample size will reveal the more effective treatment for cows at the coastal areas of Bangladesh.


GYNECOLOGY ◽  
2018 ◽  
Vol 20 (6) ◽  
pp. 48-52
Author(s):  
E N Kravchenko ◽  
R A Morgunov

The aim of the study. Assess the importance of pregravid preparation and outcomes of pregnancy and childbirth, depending on the reproductive attitudes of women in the city of Omsk. Materials and methods. The study included 92 women who were divided into groups: group A (n=43) - women whose pregnancy was planned; group B (n=49) - women whose pregnancy occurred accidentally. Each group was divided into subgroups depending on age: from 18 to 30 and from 31 to 49 years. For each patient included in the study, a specially designed map was filled out. These patients were interviewed at the City Clinical Perinatal Center. Results. Comparative analysis revealed the relationship between the reproductive settings of women of childbearing age and the peculiarity of the course of pregnancy and childbirth in these patients. Summary. The majority of women of fertile age are married: in subgroup AA - 25 (96.2%), AB - 13 (76.5%), BA - 25 (92.6%), BB - 20 (91.0%). The predominant number of women of fertile age have one or more abortions: in subgroup AA - 12 (46.2%), AB - 6 (35.3%), in subgroups of comparison BA - 8 (29.6%), BB - 6 (27.3%). More than half of the women of fertile age surveyed have a history of untreated cervical pathology (from 40.8% to 64.7%). The course of pregnancy in women planning pregnancy in most cases proceeded without complications: in subgroup AA - 13 (50.0%), AB - 11 (64.7%). The most common cause of complicated pregnancy in women whose pregnancy occurred accidentally is the threat of spontaneous miscarriage: in subgroup BA - 15 (55.6%), BB - 16 (72.7%). The uncomplicated course of labor more often [subgroup AA - 19 (73.0%), AB - 12 (70.6%)] was observed in women whose pregnancy was planned and they were motivated to give birth to a healthy child.


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