scholarly journals Sodium tetraphenylborate displays selective bactericidal activity against N. meningitidis and N. gonorrhoeae and is effective at reducing bacterial infection load.

2020 ◽  
Author(s):  
Eve Bernet ◽  
Marthe Lebughe ◽  
Antony T. Vincent ◽  
Mohammad Mehdi Haghdoost ◽  
Golara Golbaghi ◽  
...  
Keyword(s):  
Bactericidal Activity ◽  
Cell Envelope ◽  
Biological Activities ◽  
Lower Sensitivity ◽  
Healthy Individuals ◽  
Sodium Tetraphenylborate ◽  
Normal Flora ◽  
Boron Uptake ◽  
Icp Ms ◽  
Higher Doses

Neisseria meningitidis and Neisseria gonorrhoeae, two highly related species that may have emerged from a common commensal ancestor, constitute major human threats. Vaccines are available to prevent N. meningitidis infection, whereas for N. gonorrhoeae, there are only a limited number of antibiotics available. Unfortunately, some strains of these species are rapidly evolving and capable of escaping human interventions. Thus, it is now urgent to develop new avenues to fight these bacteria. This study reports that a boron-based salt, sodium tetraphenylborate (NaBPh4), displays high bactericidal activity and remarkable specificity against N. meningitidis and N. gonorrhoeae. Other closely related commensal species such as N. lactamica, found in the normal flora of healthy individuals were found to be less affected even at 5-fold higher doses of NaBPh4. This specificity was further observed where much lower sensitivity was found for the more distant Neisseriaceae (such as N. elongata or Kingella oralis) and completely unrelated species. A significant boron uptake by N. meningitidis cells was observed after incubation with 5 μM of NaBPh4, as measured by ICP-MS, suggesting that this drug candidate's target(s) could be located intracellularly or within the cell envelope. Furthermore, mutants with a slightly decreased susceptibility displayed an alteration in genes coding for cell-envelope elements, which reduced their virulence in an animal model of infection. Finally, a single dose of NaBPh4 resulted in a significant reduction in bacterial burden in a mouse model of N. meningitidis bacteremia. Although numerous boron-containing species were previously reported for their complex biological activities, the observation of this narrow selectivity is unprecedented and of potential importance from a therapeutic standpoint.

scholarly journals Mycoplasmas in Australian fur seals (Arctocephalus pusillus doriferus): identification and association with abortion

2011 ◽  
Vol 23 (6) ◽  
pp. 1123-1130 ◽  
Author(s):  
Michael Lynch ◽  
Trevor K. Taylor ◽  
Pádraig J. Duignan ◽  
Jane Swingler ◽  
Marc Marenda ◽  
...  
Keyword(s):  
Ribosomal Rna ◽  
Mycoplasma Species ◽  
Lung Pathology ◽  
Healthy Individuals ◽  
Normal Flora ◽  
Age Classes ◽  
Culture Techniques ◽  
Fur Seals ◽  
Specific Culture ◽  
Apparently Healthy

Bacteria from the genus Mycoplasma are common inhabitants of the respiratory, gastrointestinal, and genital tracts of mammals. The understanding of the pathological significance of mycoplasmas in seals is poor, as few studies have utilized the specific culture techniques required to isolate these bacteria. The current study surveyed for the Mycoplasma species present in Australian fur seals ( Arctocephalus pusillus doriferus) and investigated the association between infection and pathology. Mycoplasmas were found in the nasal cavities of 55/80 (69%) of apparently healthy individuals. Isolates from 18 individuals were investigated through 16S ribosomal RNA sequencing, and 3 species were identified: M. zalophi, M. phocae, and Mycoplasma sp. (GenBank no. EU714238.1), all of which had previously been isolated from Northern Hemisphere pinnipeds. In addition, mycoplasmas were isolated from the lungs of 4 out of 16 juveniles and 1 out of 5 adults sampled at necropsy. Isolates obtained were M. zalophi, Mycoplasma sp. EU714238.1, and M. phocicerebrale, but infection was not associated with lung pathology in these age classes. Inflammatory disease processes of the heart and/or lungs were present in 12 out of 32 (38%) aborted fetuses on microscopic examination. Predominant findings were interstitial pneumonia, pericarditis, and myocarditis. Mycoplasma phocicerebrale was isolated from the thymus of an aborted fetus, and 3 out of 11 (27%) fetuses with inflammatory heart or lung lesions were PCR-positive for Mycoplasma. In conclusion, several species of Mycoplasma are part of the normal flora of the nasal cavity of Australian fur seals, and some mycoplasmas may be associated with abortion in this species of seal.

scholarly journals Model-Driven Controlled Alteration of Nanopillar Cap Architecture Reveals its Effects on Bactericidal Activity

2020 ◽  
Vol 8 (2) ◽  
pp. 186 ◽  
Author(s):  
Taiyeb Zahir ◽  
Jiri Pesek ◽  
Sabine Franke ◽  
Jasper Van Pee ◽  
Ashish Rathore ◽  
...  
Keyword(s):  
Bactericidal Activity ◽  
Cell Envelope ◽  
Antibacterial Properties ◽  
Biophysical Model ◽  
Surface Measurement ◽  
Dependent Manner ◽  
Bending Rigidity ◽  
Nanostructured Surfaces ◽  
Model Driven ◽  
Antibacterial Surfaces

Nanostructured surfaces can be engineered to kill bacteria in a contact-dependent manner. The study of bacterial interactions with a nanoscale topology is thus crucial to developing antibacterial surfaces. Here, a systematic study of the effects of nanoscale topology on bactericidal activity is presented. We describe the antibacterial properties of highly ordered and uniformly arrayed cotton swab-shaped (or mushroom-shaped) nanopillars. These nanostructured surfaces show bactericidal activity against Staphylococcus aureus and Pseudomonas aeruginosa. A biophysical model of the cell envelope in contact with the surface, developed ab initio from the infinitesimal strain theory, suggests that bacterial adhesion and subsequent lysis are highly influenced by the bending rigidity of the cell envelope and the surface topography formed by the nanopillars. We used the biophysical model to analyse the influence of the nanopillar cap geometry on the bactericidal activity and made several geometrical alterations of the nanostructured surface. Measurement of the bactericidal activities of these surfaces confirms model predictions, highlights the non-trivial role of cell envelope bending rigidity, and sheds light on the effects of nanopillar cap architecture on the interactions with the bacterial envelope. More importantly, our results show that the surface nanotopology can be rationally designed to enhance the bactericidal efficiency.

scholarly journals Role of Antilipopolysaccharide Antibodies in Serum Bactericidal Activity against Salmonella enterica Serovar Typhimurium in Healthy Adults and Children in the United States

2013 ◽  
Vol 20 (10) ◽  
pp. 1491-1498 ◽  
Author(s):  
Estela Trebicka ◽  
Susan Jacob ◽  
Waheed Pirzai ◽  
Bryan P. Hurley ◽  
Bobby J. Cherayil
Keyword(s):  
United States ◽  
Bactericidal Activity ◽  
Salmonella Enterica ◽  
The United States ◽  
Healthy Children ◽  
Healthy Individuals ◽  
Serum Samples ◽  
Content Type ◽  
Serovar Typhimurium

ABSTRACTRecent observations from Africa have rekindled interest in the role of serum bactericidal antibodies in protecting against systemic infection withSalmonella entericaserovar Typhimurium. To determine whether the findings are applicable to other populations, we analyzed serum samples collected from healthy individuals in the United States. We found that all but 1 of the 49 adult samples tested had robust bactericidal activity againstS. Typhimurium in a standardin vitroassay. The activity was dependent on complement and could be reproduced by immunoglobulin G (IgG) purified from the sera. The bactericidal activity was inhibited by competition with soluble lipopolysaccharide (LPS) fromS. Typhimurium but not fromEscherichia coli, consistent with recognition of a determinant in the O-antigen polysaccharide. Sera from healthy children aged 10 to 48 months also had bactericidal activity, although it was significantly less than in the adults, correlating with lower levels of LPS-specific IgM and IgG. The lone sample in our collection that lacked bactericidal activity was able to inhibit killing ofS. Typhimurium by the other sera. The inhibition correlated with the presence of an LPS-specific IgM and was associated with decreased complement deposition on the bacterial surface. Our results indicate that healthy individuals can have circulating antibodies to LPS that either mediate or inhibit killing ofS. Typhimurium. The findings contrast with the observations from Africa, which linked bactericidal activity to antibodies against anS. Typhimurium outer membrane protein and correlated the presence of inhibitory anti-LPS antibodies with human immunodeficiency virus infection.

Shortlasting Effects Of Acetylsalicylic Acid (ASA) And Dipyridamole On Spontaneous And Tissue Extract Induced Platelet Stimulation And On Platelet Retention

1981 ◽  
Author(s):  
K Breddin ◽  
C M Kirchmaier ◽  
K O Trautmann ◽  
M Sehrbrock ◽  
G Reinfelder
Keyword(s):  
Myocardial Infarction ◽  
Clinical Trials ◽  
Tissue Extract ◽  
Healthy Individuals ◽  
Antithrombotic Effect ◽  
Inhibition Of Platelet Aggregation ◽  
Contrast Microscopy ◽  
Interference Contrast Microscopy ◽  
Induced Aggregation ◽  
Higher Doses

30 healthy individuals received single doses of 250,500 or 1000 mg ASA (Aspirin), 10 persons took 750 mg of an ASA preparation with retarded intestinal absorption.24 volunteers received 75 or 150 mg dipyridamole alone or together with 500 mg ASA.Spontaneous and tissue extract induced platelet stimulation were investigated using interference contrast microscopy. Collagen induced aggregation (1µg/mlPRP) was measured 30 - 45 minutes after blood sampling. Platelet retention was investigated using a modified Hellem test.Platelet stimulation and retention were inhibited for 8 - 10 hours after the intake of ASA. The higher doses had a more pronounced and longer lasting effect. The effect of 750 mg of the slowly absorbed form of ASA lasted longer than that of 1000 mg Aspirin. Platelet retention was inhibited in a similar way as platelet stimulation. No correlation between the long lasting inhibition of platelet aggregation and the shortlasting effects of ASA on platelet retention and platelet stimulation was found.It has to be established to which extent the shortlasting effects of ASA and Dipyridamole are essential for the antithrombotic effect of both drugs. If these effects are contributing to the antithrombotic effect of ASA, differences in the results of similar clinical trials as the AMIS and PARIS studies on patients with recent myocardial infarction could be explained by different dose regimens in these studies, e.g.the use of 2 × 500 against 3 × 330 mg ASA.

scholarly journals Effect of Human Immunodeficiency Virus Infection on Plasma Bactericidal Activity against Salmonella enterica Serovar Typhimurium

2014 ◽  
Vol 21 (10) ◽  
pp. 1437-1442 ◽  
Author(s):  
Estela Trebicka ◽  
Nanda Kumar N. Shanmugam ◽  
Anastassia Mikhailova ◽  
Galit Alter ◽  
Bobby J. Cherayil
Keyword(s):  
Human Immunodeficiency Virus ◽  
Bactericidal Activity ◽  
Salmonella Enterica ◽  
Hiv Positive ◽  
Healthy Controls ◽  
Elite Controllers ◽  
Healthy Individuals ◽  
Immunodeficiency Virus ◽  
Serovar Typhimurium ◽  
Specific Igg

ABSTRACTIndividuals with human immunodeficiency virus (HIV) infection have increased susceptibility to invasive disease caused bySalmonella entericaserovar Typhimurium. Studies from Africa have suggested that this susceptibility is related in part to the development of a high level of lipopolysaccharide (LPS)-specific IgG that is able to inhibit the killing ofS. Typhimurium by bactericidal antibodies in healthy individuals. To explore this issue further, we examined the bactericidal activity againstS. Typhimurium using serum and plasma samples from healthy controls and various clinical subgroups of HIV-infected adults in the United States. We found that the bactericidal activity in the samples from HIV-positive elite controllers was comparable to that from healthy individuals, whereas it was significantly reduced in HIV-positive viremic controllers and untreated chronic progressors. As demonstrated previously for healthy controls, the bactericidal activity of the plasma from the elite controllers was inhibited by preincubation withS. Typhimurium LPS, suggesting that it was mediated by anti-LPS antibodies.S. Typhimurium LPS-specific IgG was significantly reduced in all subgroups of HIV-infected individuals. Interestingly, and in contrast to the healthy controls, plasma from all HIV-positive subgroups inhibitedin vitrokilling ofS. Typhimurium by plasma from a healthy individual. Our results, together with the findings from Africa, suggest that multiple mechanisms may be involved in the HIV-induced dysregulation of humoral immunity toS. Typhimurium.

scholarly journals THE FUNCTIONAL STATUS OF NEUTROPHILS IN PATIENTS WITH CHRONIC RECURRENT INFECTIONS OF VARIOUS ETIOLOGY

2016 ◽  
pp. 48-53
Author(s):  
N. V. Gusakova ◽  
I. A. Novikova
Keyword(s):  
Functional Status ◽  
Bactericidal Activity ◽  
Acute Stage ◽  
Net Generation ◽  
No Production ◽  
Recurrent Infections ◽  
Healthy Individuals ◽  
Herpetic Infection ◽  
Recurrent Furunculosis

Objective: complex assessment of the functional status of neutrophils in patients with chronic recurrent furunculosis (CRF) and recurrent herpetic infection (RHI). Material and methods. We have studied the functional status of neutrophils: ROS-, NO-production and NET-generation, apoptosis, phagocytosis, and bactericidal ability of 103 patients with CRF and 238 patients with RHI examined during remission and exacerbation stages. Conclusion. The patients examined during remission showed the same type of the functional status changes of neutrophils in comparison with healthy individuals. The exception was the parameters of the bactericidal activity of neutrophils decreased in the patients with CRF. During the acute stage we marked the maximum changes of netosis and apoptosis. We have defined the possibility of using these data for more precise differentiation of exacerbation and remission in patients with CRF and RHI.

scholarly journals Chemical Compositions of the Essential Oil Extracted from the Seeds of Garcina Kola, and Its Biological Activities

2021 ◽  
Vol 14 (2) ◽  
pp. 607-621
Author(s):  
Olagoke Zacchaeus Olatunde ◽  
Danian Tian ◽  
Jianping Yong ◽  
Canzhong Lu
Keyword(s):  
Essential Oil ◽  
Biological Activities ◽  
Chemical Compositions ◽  
Anticancer Activities ◽  
Potent Inhibition ◽  
Icp Ms ◽  
Hela Cell Lines ◽  
Long Time ◽  
Human Breast Carcinoma Cells

The essential oil was obtained from the seeds of Garcina kola and its compositions were investigated by GC-MS and ICP-MS, respectively. 74 organic compounds and 9 trace elements beneficial to human health were confirmed in this oil. Then, the in vitro antioxidant and anticancer activities were evaluated accordingly. The results showed that this essential oil exhibited stronger antioxidant activity against DPPH⸱ with the scavenging rate of 94.19% at 0.2 mg/mL, as well as potent inhibition against gastric cancer, lung cancer(A549) and Hela cell lines with the inhibitions of 96.397%±0.929, 98.005%±0.513 and 94.77±2.09 respectively at 8.3 mg/mL. While it exhibited moderate inhibition against the human breast carcinoma cells (MCF-7) with the inhibition of 59.257%±4.544 at 8.3mg/mL. In consideration of Garcina kola being consumed in Nigeria for a long time, this essential oil obtained from the Garcina kola can be used in the field of food, cosmetic or drugs.

Candidiasis of the Larynx

1973 ◽  
Vol 82 (6) ◽  
pp. 812-815 ◽  
Author(s):  
A. J. Yonkers
Keyword(s):  
Foreign Bodies ◽  
Topical Therapy ◽  
Invasive Disease ◽  
Immunosuppressive Drugs ◽  
Healthy Individuals ◽  
Normal Flora ◽  
Cutaneous Lesions ◽  
Specific Therapy ◽  
Mucus Membrane ◽  
Candida Infections

Candida albicans, the fungus which is responsible for moniliasis, is a common inhabitant of the throat and not ordinarily a pathogen in the adult. In the presence of lowered host resistance by disease, corticosteroid therapy, immunosuppressive drugs or in the presence of altered normal flora by prolonged use of broad spectrum antibiotics, a candida infection may occur. Usually there is little difficulty in assessing the significance of this fungus when it is associated with visible mucus membrane or cutaneous lesions in healthy individuals. However, multiple or persistent isolations of the fungus from body fluids even after the removal of provocative factors such as antibiotics and foreign bodies indicates an invasive disease which requires specific therapy. Mucocutaneous and superficial Candida infections usually respond to topical therapy such as nystatin spray or gargle. When this is ineffective and the patient is still symptomatic, low doses of intravenously administered amphotercin B should be considered as the next step in the management of the infection. In patients with Candida meningitis or endocarditis this regimen is not recommended.

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