Role of Capsule in Pulmonary Hypertension Induced by Group B Streptococcus

The article by Bortolussi et al. on pneumococcal septicemia and meningitis in the neonat (Pediatrics 60:352, September 1977) was of great interest to us, since we have been analyzing the effect of antibody directed against Streptococcus pneumoniae on group B Streptococcus type III. We have recently shown (unpublished data) that antibody directed against S. pneumoniae type 14 precipitates the hot hydrochloric acid-extracted polysaccharide antigen of group B Streptococcus type III. Further studies have shown that this antibody is opsonic for group B Streptococcus type III in an in vitro bactericidal assay and protective in a suckling rat model of group B Streptococcus type III sepsis.1

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Maternal colonization with group B Streptococcus and prelabor rupture of membranes at term: The role of induction of labor

American Journal of Obstetrics and Gynecology ◽

10.1016/s0002-9378(97)70268-0 ◽

1997 ◽

Vol 177 (4) ◽

pp. 780-785 ◽

Cited By ~ 42

Author(s):

Mary E. Hannah ◽

Arne Ohlsson ◽

Elaine E.L. Wang ◽

Anne Matlow ◽

Gary A. Foster ◽

...

Keyword(s):

Group B Streptococcus ◽

Induction Of Labor ◽

Prelabor Rupture Of Membranes ◽

Group B

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Diaphragmatic failure during group B streptococcal sepsis in piglets: the role of thromboxane A2

Journal of Applied Physiology ◽

10.1152/jappl.1995.78.2.491 ◽

1995 ◽

Vol 78 (2) ◽

pp. 491-498 ◽

Cited By ~ 10

Author(s):

T. D. Murphy ◽

R. L. Gibson ◽

T. A. Standaert ◽

D. E. Woodrum

Keyword(s):

Group B Streptococcus ◽

Thromboxane A2 ◽

Treated Group ◽

Arachidonic Acid Metabolism ◽

Group 4 ◽

Group 2 ◽

Txa2 Receptor Antagonist ◽

Group B ◽

Spontaneously Breathing

Group B Streptococcus (GBS) causes an impairment of diaphragmatic pressure generation (Pdi) in 2-wk-old piglets, whereas 4-wk-old piglets are unaffected. In this study, we examined the effect on 4-wk-old piglets of a higher dose of GBS than previously utilized. We sought to determine whether an eicosanoid product of arachidonic acid metabolism accounted for the decrease in Pdi during GBS infusion and whether thromboxane A2 (TxA2) is the putative eicosanoid mediator of decreased Pdi during GBS infusion. Measuring Pdi during phrenic nerve stimulation, we studied four groups of anesthetized spontaneously breathing 4-wk-old piglets. Group 1 (GBS) was infused with live GBS, which caused a decrease in Pdi by 1 h at 20-, 30-, 50-, and 100-Hz stimulation frequencies. Group 2 [GBS + indomethacin (Indo)] was pretreated with Indo before GBS infusion. In the GBS + Indo group, Pdi did not decrease throughout 4 h of GBS infusion. Because Indo proved to be protective of Pdi during GBS infusion, we examined the role of TxA2, the only eicosanoid present at 1 h in the serum of GBS-infused piglets. Group 3 was infused with the TxA2 analogue U-46619 only for 1 h. Group 4 was treated with the TxA2-receptor antagonist SQ-29548 before and concomitant with GBS infusion for 1 h; the SQ-29548 was then discontinued, and GBS was continued for 1 h more. In the U-46619-infused group, Pdi decreased at 1 h, and in the SQ-29548-treated group, Pdi did not decrease during GBS infusion.(ABSTRACT TRUNCATED AT 250 WORDS)

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Comparative Disposition Kinetics of 111ln-Labeled Group B Streptococcus and Neutrophils during Onset of Sepsis-Induced Pulmonary Hypertension

Neonatology ◽

10.1159/000243916 ◽

1993 ◽

Vol 63 (2) ◽

pp. 86-95 ◽

Cited By ~ 2

Author(s):

Shewan M. Aziz ◽

Erik P. Sandefer ◽

Thomas H. Pauly ◽

Mark N. Gillespie

Keyword(s):

Pulmonary Hypertension ◽

Group B Streptococcus ◽

Disposition Kinetics ◽

Group B ◽

Kinetics Of

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OR09: The role of zinc homeostasis in Group B Streptococcus biofilm formation in vitro and in an instrumented fetal membrane on a chip

American Journal of Reproductive Immunology ◽

10.1111/aji.08_13119 ◽

2019 ◽

Vol 81 (S1) ◽

pp. 30-30

Keyword(s):

Biofilm Formation ◽

Group B Streptococcus ◽

Zinc Homeostasis ◽

Fetal Membrane ◽

Group B

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Role of PCR in Rapid Detection Group B Streptococcus in Pregnant Females in Al-Quwayiyah General Hospital, Riyadh, Saudi Arabia

Microbiology Research Journal International ◽

10.9734/mrji/2021/v31i330305 ◽

2021 ◽

pp. 45-52

Author(s):

E. S. Khater ◽

A. S. Abdel-Motaal

Keyword(s):

Saudi Arabia ◽

Pregnant Women ◽

General Hospital ◽

Antimicrobial Susceptibility ◽

Gestational Age ◽

Group B Streptococcus ◽

Predictive Values ◽

Pregnant Females ◽

Group B

Background: Group B streptococcus is one of the most common causes of severe neonatal infections. Aim: To detect the prevalence of group B. Streptococcus and their antimicrobial susceptibility and to assess the role of PCR as a rapid method of its detection. Place and Duration of the Study: A cross sectional and prospective cohort study was carried out from September 2019 to February 2020 in Gynaecology and Obstetrics OPD and inpatient units in Al- Quwayiyah General hospital, Riyadh, Saudi Arabia Methodology: Paired rectal/vaginal specimens were collected from 540 pregnant females with gestational age 35 or more, Each swab was inoculated into selective medium, Todd Hewitt, One swab is streaked onto blood agar plates incubated in 5% CO2 for 24h at 36ºC. β-hemolytic colonies growth is identified by Gram’s stain, colony morphology and CAMP test. The confirmation and antimicrobial susceptibility were done by Vitek II machine, The second swab was used for PCR to identify atr gene. Results: Out of 540 pregnant women 87 (16.1%) were colonized with GBS isolates. The positive GBS women aged 25 (22-34) and negative GBS women aged 23 (24-35) with no statistical difference. Patients aged more than 35 years old has the higher rate of positive GBS, 46.2%. No significant association detected between GBS and gestational age at delivery, antenatal visits, BMI and gravidity. The GBS strains isolated from pregnant women was 100% susceptible to linezolid and vancomycin followed by ampicillin (93.1%) and tobramicin (83.9%) then gentamicin (81.6%) and levofloxacin(78.2%) and showed least antibiotic susceptibility to erythromycin (26.4%). The PCR was positive in 145 (26.9%). Using culture as gold method, PCR sensitivity was 100% (95% CI: 91.62-100), while specificity was 83.2% (95% CI: 82.61-91.02). Negative and positive predictive values were 100% and 61% respectively. Kappa between the two methods was 0.71, which indicate major agreement. Conclusion: The GBS prevalence among the pregnant females in Al Quwayiyah General Hospital was 16.1%. Detection of GBS using new PCR technique was found to have high sensitivity and faster results, allowing efficient management of GBS and reduction in newborn morbidity and mortality however the cost is high for some laboratories. Further studies should be assessed to be both low cost and accurate rapid screening.

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A type VII secretion system in Group B Streptococcus mediates cytotoxicity and virulence

PLoS Pathogens ◽

10.1371/journal.ppat.1010121 ◽

2021 ◽

Vol 17 (12) ◽

pp. e1010121

Author(s):

Brady L. Spencer ◽

Uday Tak ◽

Jéssica C. Mendonça ◽

Prescilla E. Nagao ◽

Michael Niederweis ◽

...

Keyword(s):

Group B Streptococcus ◽

Bioinformatic Analysis ◽

Effector Proteins ◽

Dependent Manner ◽

Secretion Systems ◽

Gram Positive Bacteria ◽

Type Vii Secretion ◽

Type Vii Secretion System ◽

Group B

Type VII secretion systems (T7SS) have been identified in Actinobacteria and Firmicutes and have been shown to secrete effector proteins with functions in virulence, host toxicity, and/or interbacterial killing in a few genera. Bioinformatic analysis indicates that isolates of Group B Streptococcus (GBS) encode at least four distinct subtypes of T7SS machinery, three of which encode adjacent putative T7SS effectors with WXG and LXG motifs. However, the function of T7SS in GBS pathogenesis is unknown. Here we assessed the role of the most abundant GBS T7SS subtype during GBS pathogenesis. In a murine model of hematogenous meningitis, mice infected with GBS lacking a functional T7SS or lacking the secreted WXG100 effector EsxA exhibited less mortality, lower bacterial burdens in tissues, and decreased inflammation in the brain compared to mice infected with the parental GBS strain. We further showed that this T7SS induces cytotoxicity in brain endothelium and that EsxA contributes to these cytotoxicity phenotypes in a WXG motif-dependent manner. Finally, we determined that EsxA is a pore-forming protein, thus demonstrating the first role for a non-mycobacterial EsxA homolog in pore formation. This work reveals the importance of a T7SS in host–GBS interactions and has implications for T7SS effector function in other Gram-positive bacteria.

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