Protective role of IL-18 in host defenses against group B Streptococcus

2021 ◽  
Author(s):  
G. Mancuso ◽  
A. Midiri ◽  
C. Beninati ◽  
S. Zummo ◽  
C. Biondo
Keyword(s):  
Group B Streptococcus ◽  
Protective Role ◽  
Host Defenses ◽  
Group B

scholarly journals Lactobacillus rhamnosus reduces the cytotoxic effects of Group B Streptococcus on HeLa cells

2021 ◽  
Author(s):  
Jan Mikhale B Cajulao ◽  
Lily Chen
Keyword(s):  
Hela Cell ◽  
Hela Cells ◽  
Group B Streptococcus ◽  
Lactobacillus Rhamnosus ◽  
Protective Role ◽  
Lactobacillus Species ◽  
Sem Images ◽  
Vaginal Tract ◽  
Group B

Group B Streptococcus (GBS) is an opportunistic pathogen found in the vaginal tract and is a leading cause of preterm birth and neonatal illness. Aside from GBS, the vaginal tract is predominantly colonized by commensal Lactobacillus species that are thought to protect the vaginal tract from pathogens, including GBS. Studies that examined if, and how Lactobacilli modulate GBS pathogenicity remain limited. This study sought to investigate the potential protective role of Lactobacillus rhamnosus against GBS, using an in vitro model system. Immunofluorescence microscopy and Scanning Electron Microscopy (SEM) captured images of infected HeLa cells and were analyzed using the image analysis program ImageJ. Results indicate that GBS causes HeLa cell detachment unless L. rhamnosus is present. SEM images show that GBS reduces length and number of microvilli on HeLa cell surface, as well as size of secreted vesicles. L. rhamnosus partially inhibits GBS-dependent microvilli and vesicle disruption. GBS also disrupts HeLa cell F-actin fibers unless L. rhamnosus is present. These results reveal effects of GBS infection on the host cell cytoskeleton and implies a protective role of L. rhamnosus against GBS colonization.

Group B Streptococcal and Pneumococcal Sepsis in Newborn Infants: The Role of Pneumococcal Antibody

PEDIATRICS ◽  
1978 ◽  
Vol 62 (4) ◽  
pp. 620-621
Author(s):  
Gerald W. Fischer ◽  
James W. Bass ◽  
George H. Lowell ◽  
Martin H. Crumrine
Keyword(s):  
Streptococcus Pneumoniae ◽  
Hydrochloric Acid ◽  
Group B Streptococcus ◽  
Newborn Infants ◽  
Polysaccharide Antigen ◽  
Type Iii ◽  
Pneumococcal Sepsis ◽  
Group B

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

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

1997 ◽  
Vol 177 (4) ◽  
pp. 780-785 ◽  
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

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

1995 ◽  
Vol 78 (2) ◽  
pp. 491-498 ◽  
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)

scholarly journals The Effect of a Mediterranean Meal on Sprague Dawley Rats DMBA-Induced Mammary Tumors

2010 ◽  
Vol 3 ◽  
pp. CGM.S5894
Author(s):  
Paula C. Pereira ◽  
A. Filipa Vicente ◽  
Maria F. Mesquita ◽  
Antonio S. Cabrita
Keyword(s):  
Experimental Studies ◽  
Protective Role ◽  
Female Rats ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Total Cancer ◽  
Group A ◽  
Histopathologic Analysis ◽  
Group B

The present study intents to find a possible protective role of a Mediterranean type meal on mammary carcinogenesis. Several factors have been associated with breast cancer risk, genetics and environment are the most pointed out in epidemiologic and experimental studies. Diet is an environmental factor that can promote or prevent disease, being responsible for almost 35% of total cancer cases. A total of 72 female rats 50 days old were randomly divided in three groups of 24 rats and housed 4 in each plastic cage in a holding room under constant conditions of 22 ± 2 °C, 55 ± 10% humidity and a 12 h light/dark cycle. All the animals were submitted to the administration of 20 mg of 7, 12 dimethylbenzanthracene (DMBA) in olive oil, by gavages, except group A. The same defined standard food was provided for all the animals in group A and B, supplemented with a Mediterranean meal in group C. All the animals were sacrificed by the end of 150 days. Total carcinoma number did not differ significantly between Groups B and C and there were not found any neoplastic lesions in Group A. Most tumors showed a mixed architectural pattern, with cribriform and papillary areas, comedocarcinoma and necrosis was only seen in Group B. Histopathologic analysis showed that Group C tumors had lower mitotic activity and Pattern Grades, but higher Nuclear Grades. Mediterranean diet type meal showed lower Pattern Grades and lower Mitotic count in spite of that a higher nuclear pleomorphism was also found. Even so, tumors from Group C were better differentiated which can indicate lower malignancy.

scholarly journals Role of Capsule in Pulmonary Hypertension Induced by Group B Streptococcus

1992 ◽  
Vol 31 (4) ◽  
pp. 386-390 ◽  
Author(s):  
Joseph B Philips ◽  
Jia-Xian Li ◽  
Barry M Gray ◽  
David G Pritchard ◽  
James R Oliver
Keyword(s):  
Pulmonary Hypertension ◽  
Group B Streptococcus ◽  
Group B

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

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.

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

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.

scholarly journals Protective Role of Different Local Spices on Lambda Cyhalothrin Induced Nephrotoxicity in Male Mice

2021 ◽  
pp. 61-70
Author(s):  
Eme Efioanwan Orlu ◽  
Adetutu Olubunmi Obulor
Keyword(s):  
Experimental Design ◽  
Total Protein ◽  
Protective Role ◽  
Male Mice ◽  
Lambda Cyhalothrin ◽  
Significant Difference ◽  
Group A ◽  
Group B ◽  
Animal House

Aim: This study was aimed at evaluating the protective role of different local spices on lambda cyhalothrin induced nephrotoxicity in male mice Experimental Design: A completely randomized experimental design using standard methods for analysis. Place and Duration of Study: This study was carried out in the Animal house, Department of Animal and Environmental Biology of Rivers State University, Nkpolu-Oroworukwo Port Harcourt, Nigeria. GPS 4o47'50''N 6o58'49''E. This study lasted for 35days. Methodology: The experimental animals were separated into 6 groups (A-F) of seven mice each. Group A served as the control and Group B – F served as the test groups. At the end of the 35 day treatment period, feed was withdrawn from the mice 24 hours before termination of the experiment. Blood samples for analysis of kidney function test were collected from each mouse by ocular puncture into plain tubes. The blood was allowed to clot and centrifuged at 2500g to separate the serum from the cells. Total protein was analyzed using the spectrophotometric method of biuret, Bradford and erythrosine – b, albumin was estimated, creatinine and urea was done using enzymatic method. Vital organs were removed and weighed for organosomatic indices. Histological sections of the kidney were mounted on slides, stained with hematoxylin and eosin (H&E). Photomicrographs were generated. Results: There is no significant difference (P=0.05) between the organ weight and bodyweight in group A compared with the treatment groups. The values of Albumin, total protein, urea, creatinine and total bilirubin increased significantly in group B administered lambda cyhalothrin alone but decreased in groups administered the local spices. Histopathological analysis of the kidney shows the regular structure of the kidney architecture in group A, tubular degeneration and several vacuolations were observed in group B. However, less degeneration of the epithelial cells, regeneration of renal tubular epithelium were observed in groups C- F. Conclusion: Based on the results from liver biomarkers and histological micrographs from this study, pronounced degeneration was observed in the kidney cells exposed to lambda-cyhalothrin only. Moreover, all spices used had a regenerating ability on the kidney tubules. It is advocated therefore that consumption of this spices either singly or in combination should be encouraged especially for those exposed to insecticides poisoning

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