STUDIES OF POLYMORPHONUCLEAR LEUKOCYTES FROM PATIENTS WITH CHRONIC GRANULOMATOUS DISEASE OF CHILDHOOD: BACTERICIDAL CAPACITY FOR STREPTOCOCCI

PEDIATRICS ◽  
1968 ◽  
Vol 41 (3) ◽  
pp. 591-599
Author(s):  
Edward L. Kaplan ◽  
Throstur Laxdal ◽  
Paul G. Quie

Polymorphonuclear leukocytes (PMNs) from children with chronic granulomatous disease of childhood have been shown to readily phagocytize staphylococci and certain gram-negative bacteria, but they demonstrate an impaired intracellular bactericidal capacity for these organisms. The in vitro phagocytic and bactericidal capacities of PMNs from three patients with this disease for four species of streptococci (Streptococcus faecalis, Streptococcus viridans, microaerophlic streptococci, and Streptococcus pyogenes) were tested by the modified method of Maaloe. The PMNs obtained from the patients phagocytized and killed the four species of streptococci in a normal manner while still showing the defect for Staph. aureus and S. marcescens. Morphologic examination of coverslip preparations of PMNs revealed minimal post-phagocytic degranulation and vacuole formation when either staphylococci and serratia or the streptococcal species were tested. This suggests that different intracellular mechanisms may be responsible for the streptococcal killing. These observations are in accord with the clinical courses of these patients, who rarely have serious streptococcal infections in contrast to the frequent and life-threatening infections caused by staphylococci and some gram-negative bacteria.

PEDIATRICS ◽  
1972 ◽  
Vol 50 (2) ◽  
pp. 264-270
Author(s):  
Paul G. Quie

Serum from most normal persons contains specific antibodies which react with common bacterial species preparing their surfaces so that phagocytosis by leukocytes can take place. The Fab part of these antibodies reacts with immunologic specificity with antigens on the surface of bacteria. Another part of the immunoglobulin molecule termed the Fc portion is activated during the attachment of the Fab portion to bacteria and becomes a site for attachment of bacteria to receptors on the surface of phagocytic cells. This activity is greatly amplified by heat-labile serum factors. Normally bacteria are rapidly killed by human polymorphonuclear leukocytes after engulfment occurs. However staphylococci and gram-negative species of bacteria survive in the leukocytes of patients with the syndrome "Chronic Granulomatous Disease of Childhood." These patients have suffered recurrent severe infections with bacterial species that are part of the body's resident bacterial flora. By contrast these patients are not at increased risk to infection from such pyogenic bacterial species as group A streptococci or pneumococci. The leukocytes from patients with chronic granulomatous disease produce little hydrogen peroxide during phagocytosis. Catalase-producing staphylococci and gram-negative bacteria are not killed, but hydrogen peroxide-producing streptococci and pneumococci are killed. A normal metabolic response to phagocytosis as well as release of lysosonial factors are essential for the bactericidal activity of human polymorphonuclear leukocytes.


2020 ◽  
Vol 20 (3) ◽  
pp. 192-208 ◽  
Author(s):  
Talita Odriane Custodio Leite ◽  
Juliana Silva Novais ◽  
Beatriz Lima Cosenza de Carvalho ◽  
Vitor Francisco Ferreira ◽  
Leonardo Alves Miceli ◽  
...  

Background: According to the World Health Organization, antimicrobial resistance is one of the most important public health threats of the 21st century. Therefore, there is an urgent need for the development of antimicrobial agents with new mechanism of action, especially those capable of evading known resistance mechanisms. Objective: We described the synthesis, in vitro antimicrobial evaluation, and in silico analysis of a series of 1H-indole-4,7-dione derivatives. Methods: The new series of 1H-indole-4,7-diones was prepared with good yield by using a copper(II)- mediated reaction between bromoquinone and β-enamino ketones bearing alkyl or phenyl groups attached to the nitrogen atom. The antimicrobial potential of indole derivatives was assessed. Molecular docking studies were also performed using AutoDock 4.2 for Windows. Characterization of all compounds was confirmed by one- and two-dimensional NMR techniques 1H and 13C NMR spectra [1H, 13C – APT, 1H x 1H – COSY, HSQC and HMBC], IR and mass spectrometry analysis. Results: Several indolequinone compounds showed effective antimicrobial profile against Grampositive (MIC = 16 µg.mL-1) and Gram-negative bacteria (MIC = 8 µg.mL-1) similar to antimicrobials current on the market. The 3-acetyl-1-(2,5-dimethylphenyl)-1H-indole-4,7-dione derivative exhibited an important effect against different biofilm stages formed by a serious hospital life-threatening resistant strain of Methicillin-Resistant Staphylococcus aureus (MRSA). A hemocompatibility profile analysis based on in vitro hemolysis assays revealed the low toxicity effects of this new series. Indeed, in silico studies showed a good pharmacokinetics and toxicological profiles for all indolequinone derivatives, reinforcing their feasibility to display a promising oral bioavailability. An elucidation of the promising indolequinone derivatives binding mode was achieved, showing interactions with important sites to biological activity of S. aureus DNA gyrase. These results highlighted 3-acetyl-1-(2-hydroxyethyl)-1Hindole- 4,7-dione derivative as broad-spectrum antimicrobial prototype to be further explored for treating bacterial infections. Conclusion: The highly substituted indolequinones were obtained in moderate to good yields. The pharmacological study indicated that these compounds should be exploited in the search for a leading substance in a project aimed at obtaining new antimicrobials effective against Gram-negative bacteria.


ACS Omega ◽  
2021 ◽  
Author(s):  
Faizan Abul Qais ◽  
Mohammad Shavez Khan ◽  
Iqbal Ahmad ◽  
Fohad Mabood Husain ◽  
Rais Ahmad Khan ◽  
...  

2006 ◽  
Vol 50 (6) ◽  
pp. 2261-2264 ◽  
Author(s):  
Hee-Soo Park ◽  
Hyun-Joo Kim ◽  
Min-Jung Seol ◽  
Dong-Rack Choi ◽  
Eung-Chil Choi ◽  
...  

ABSTRACT DW-224a showed the most potent in vitro activity among the quinolone compounds tested against clinical isolates of gram-positive bacteria. Against gram-negative bacteria, DW-224a was slightly less active than the other fluoroquinolones. The in vivo activities of DW-224a against gram-positive bacteria were more potent than those of other quinolones.


2006 ◽  
Vol 50 (7) ◽  
pp. 2478-2486 ◽  
Author(s):  
Andrea Giacometti ◽  
Oscar Cirioni ◽  
Roberto Ghiselli ◽  
Federico Mocchegiani ◽  
Fiorenza Orlando ◽  
...  

ABSTRACT Sepsis remains a major cause of morbidity and mortality in hospitalized patients, despite intense efforts to improve survival. The primary lead for septic shock results from activation of host effector cells by endotoxin, the lipopolysaccharide (LPS) associated with cell membranes of gram-negative bacteria. For these reasons, the quest for compounds with antiendotoxin properties is actively pursued. We investigated the efficacy of the amphibian skin antimicrobial peptide temporin L in binding Escherichia coli LPS in vitro and counteracting its effects in vivo. Temporin L strongly bound to purified E. coli LPS and lipid A in vitro, as proven by fluorescent displacement assay, and readily penetrated into E. coli LPS monolayers. Furthermore, the killing activity of temporin L against E. coli was progressively inhibited by increasing concentrations of LPS added to the medium, further confirming the peptide's affinity for endotoxin. Antimicrobial assays showed that temporin L interacted synergistically with the clinically used β-lactam antibiotics piperacillin and imipenem. Therefore, we characterized the activity of temporin L when combined with imipenem and piperacillin in the prevention of lethality in two rat models of septic shock, measuring bacterial growth in blood and intra-abdominal fluid, endotoxin and tumor necrosis factor alpha (TNF-α) concentrations in plasma, and lethality. With respect to controls and single-drug treatments, the simultaneous administration of temporin L and β-lactams produced the highest antimicrobial activities and the strongest reduction in plasma endotoxin and TNF-α levels, resulting in the highest survival rates.


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