ASSESSMENT OF ANTIMYCOBACTERIAL ACTIVITY OF PROPYLTHIADIAZOLOQUINAZOLINE DERIVATIVES AGAINST MYCOBACTERIUM INTRACELLULARE

2021 ◽  
Vol 92 (2) ◽  
pp. 93-100
Author(s):  
O. G. Sechko ◽  
N. S. Gurina ◽  
V. M. Tsarenkov ◽  
I. N. Slabko ◽  
F. Macaev ◽  
...  
Keyword(s):  
Nutrient Medium ◽  
Antimycobacterial Activity ◽  
Visual Assessment ◽  
Mycobacterium Intracellulare ◽  
Series Of Experiments ◽  
Solid Nutrient Medium ◽  
Academy Of Sciences ◽  
Comprehensive Study

The compounds studied are propylthiadiazoloquinazoline derivatives, tryptanthrin analogs. Tryptantrin and its derivatives were found to have different antimycobacterial activity in vitro and in vivo. This series of experiments is devoted to the study of antimycobacterial activity of three propylthiadiazoloquinazoline derivatives obtained in the laboratory of organic synthesis and Biopharmaceutics of the Institute of Chemistry of the Academy of Sciences in Moldova using a non-tuberculous strain of Mycobacterium intracellulare, which is a part of the Mycobacterium avium complex (MAC). Species of the MAC are one of the main pathogen types causing mycobacteriosis. In this regard, propylthiadiazoloquinazoline derivatives are of interest for a comprehensive study as a potential antimycobacterial drug. To study antimycobacterial activity the method of dilutions in a dense nutrient medium of Middlebrook 7H9 broth with glycerol in Petri dishes was used. To assess antimycobacterial activity visual assessment of M. intracellulare growth in a solid nutrient medium was used. It is shown that the compounds studied inhibit M. Intracellulare growth. The most active compound was compound № 1 - 2-mercapto-5H-[1,3,4]-thiadiazolo-[2,3-b]-quinazoline-5-one.

scholarly journals Biofilm formation in the lung contributes to virulence and drug tolerance of Mycobacterium tuberculosis

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Poushali Chakraborty ◽  
Sapna Bajeli ◽  
Deepak Kaushal ◽  
Bishan Dass Radotra ◽  
Ashwani Kumar
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Immune System ◽  
Biofilm Formation ◽  
Antimycobacterial Activity ◽  
Drug Tolerance ◽  
Host Immune System ◽  
Tissue Sections ◽  
Slow Growing

AbstractTuberculosis is a chronic disease that displays several features commonly associated with biofilm-associated infections: immune system evasion, antibiotic treatment failures, and recurrence of infection. However, although Mycobacterium tuberculosis (Mtb) can form cellulose-containing biofilms in vitro, it remains unclear whether biofilms are formed during infection in vivo. Here, we demonstrate the formation of Mtb biofilms in animal models of infection and in patients, and that biofilm formation can contribute to drug tolerance. First, we show that cellulose is also a structural component of the extracellular matrix of in vitro biofilms of fast and slow-growing nontuberculous mycobacteria. Then, we use cellulose as a biomarker to detect Mtb biofilms in the lungs of experimentally infected mice and non-human primates, as well as in lung tissue sections obtained from patients with tuberculosis. Mtb strains defective in biofilm formation are attenuated for survival in mice, suggesting that biofilms protect bacilli from the host immune system. Furthermore, the administration of nebulized cellulase enhances the antimycobacterial activity of isoniazid and rifampicin in infected mice, supporting a role for biofilms in phenotypic drug tolerance. Our findings thus indicate that Mtb biofilms are relevant to human tuberculosis.

Vasopressin-induced pulmonary vasodilation in rats

1989 ◽  
Vol 257 (2) ◽  
pp. H415-H422 ◽  
Author(s):  
B. R. Walker ◽  
J. Haynes ◽  
H. L. Wang ◽  
N. F. Voelkel
Keyword(s):  
Hypoxic Pulmonary Vasoconstriction ◽  
Systemic Resistance ◽  
Constant Infusion ◽  
Bolus Administration ◽  
Pulmonary Hemodynamics ◽  
Pulmonary Vasodilation ◽  
Isolated Lung ◽  
Series Of Experiments

Experiments were performed to determine the pulmonary vascular responses to exogenous or endogenous arginine vasopressin (AVP) in rats. Both in vitro and in vivo approaches were used to examine the direct pulmonary vasoactive properties of AVP and how those properties affect pulmonary hemodynamics in the intact animal. In conscious, unrestrained rats, constant infusion of AVP (4.0 mU.kg-1.min-1 iv) resulted in a fall in mean pulmonary artery pressure (PAP), although systemic pressure was increased. Coincident with the fall in PAP were similar reductions in cardiac output and heart rate. Similarly, bolus administration of AVP reduced PAP, and this effect was augmented during hypoxia. Another series of experiments examined the effect of endogenous AVP released by arterial hypoxemia on pulmonary hemodynamics in conscious rats. Administration of a specific V1-vasopressinergic antagonist had no effect on the PAP response to hypoxia; however, systemic resistance tended to fall following V1-antagonism. To determine the vasoactive properties of AVP independent of these changes in blood flow, a series of experiments were performed on isolated, perfused rat lungs. Injection of 25, 200, or 2,000 mU of AVP into the circulation of the isolated lung was without effect under normoxic conditions. In contrast, 25 mU AVP elicited reproducible pulmonary vasodilation when injected during ongoing hypoxic pulmonary vasoconstriction. This vasodilatory response was unaffected by meclofenamate or by the platelet-activating factor receptor antagonist SRI 63-441, but was blocked by a specific V1-vasopressinergic antagonist. We conclude that although AVP exerts profound systemic vasoconstriction, the pulmonary circulation appears relatively unaffected by exogenous or endogenous AVP in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)

A Comprehensive Study of Osteogenic Calcium Phosphate Silicate Cement: Material Characterization and In Vitro/In Vivo Testing

2015 ◽  
Vol 5 (4) ◽  
pp. 457-466 ◽  
Author(s):  
Tianxing Gong ◽  
Zhiqin Wang ◽  
Yixi Zhang ◽  
Yubiao Zhang ◽  
Mingxiao Hou ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Material Characterization ◽  
Cement Material ◽  
Phosphate Silicate ◽  
In Vivo Testing ◽  
Comprehensive Study

Development of embryonic rat eyes in organ culture

Development ◽  
1968 ◽  
Vol 19 (3) ◽  
pp. 407-414
Author(s):  
R. Christy Armstrong ◽  
Joel J. Elias
Keyword(s):  
Organ Culture ◽  
Culture Medium ◽  
Folic Acid Deficiency ◽  
Experimental Conditions ◽  
Acid Deficiency ◽  
Series Of Experiments ◽  
Development In Vitro ◽  
Ocular System

Abnormalities of the ocular system which appear in organ culture in Waymouth's medium with freshly added glutamine (Armstrong & Elias, 1968) resemble those caused by transitory pteryolglutamic acid (PGA or folic acid) deficiency in vivo (Armstrong & Monie, 1966). The configurations of such malformations as lens herniations, retinal diverticula, and rosette-like formations of the retina are remarkably similar in both cases. The experiments reported in this paper were undertaken in an effort to understand the mechanisms involved in the production of similar abnormalities by two very different experimental conditions: the addition of glutamine in vitro and the transitory deficiency of PGA in vivo. One series of experiments involved the effects of manipulation of the PGA and glutamine content of the culture medium on eye development in vitro. Parallel studies on PGA-deficiency in vivo were undertaken in conjunction with organ-culture experiments in order to compare the effects on abnormal eye morphogenesis.

The first comprehensive study of praziquantel effects in vivo and in vitro on European liver fluke Opisthorchis felineus (Trematoda)

2015 ◽  
Vol 46 (1) ◽  
pp. 94-100 ◽  
Author(s):  
Mariya Y. Pakharukova ◽  
Alexander G. Shilov ◽  
Darya S. Pirozhkova ◽  
Alexey V. Katokhin ◽  
Viatcheslav A. Mordvinov
Keyword(s):  
Liver Fluke ◽  
Opisthorchis Felineus ◽  
Comprehensive Study

scholarly journals B-1 cell: the precursor of a novel mononuclear phagocyte with immuno-regulatory properties

2009 ◽  
Vol 81 (3) ◽  
pp. 489-496 ◽  
Author(s):  
José Daniel Lopes ◽  
Mario Mariano
Keyword(s):  
Mammalian Cells ◽  
Giant Cells ◽  
Mononuclear Phagocyte ◽  
Different Types ◽  
Series Of Experiments ◽  
B1 Cells ◽  
Regulatory Properties

Characterization of the origin, properties, functions and fate of cells is a fundamental task for the understanding of physiological and pathological phenomena. Despite the bulk of knowledge concerning the diverse characteristics of mammalian cells, some of them, such as B-1 cells, are still poorly understood. Here we report the results obtained in our laboratory on these cells in the last 10 years. After showing that B-1 cells could be cultured and amplified in vitro, a series of experiments were performed with these cells. They showed that B1 cells reside mostly in the peritoneal and pleural cavities, migrate to distant inflammatory foci, coalesce to form giant cells and participate in granuloma formation, both in vitro and in vivo. They are also able to present antigens to immunologically responsive cells and are endowed with regulatory properties. Further, we have also shown that these cells facilitate different types of infection as well as tumor growth and spreading. These data are presently reviewed pointing to a pivotal role that these cells may play in innate and acquired immunity.

Comprehensive Study of Evodia rutaecarpa-induced Contraction on Blood Vascular in Vivo and in Vitro

2011 ◽  
Vol 9 (1) ◽  
pp. 65-73
Author(s):  
Xiu-Kun WANG ◽  
Yu-Gang WANG ◽  
Hong-Lei ZHAN ◽  
Yu-Shuang CHAI ◽  
Jun HU ◽  
...  
Keyword(s):  
Evodia Rutaecarpa ◽  
Comprehensive Study

scholarly journals Ambroxol Induces Autophagy and Potentiates Rifampin Antimycobacterial Activity

2018 ◽  
Vol 62 (9) ◽  
Author(s):  
Seong Won Choi ◽  
Yuexi Gu ◽  
Ryan Scott Peters ◽  
Padmini Salgame ◽  
Jerrold J. Ellner ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Antimycobacterial Activity ◽  
Lead Compound ◽  
Content Type ◽  
Tuberculosis Model

ABSTRACT Host-directed therapy in tuberculosis is a potential adjunct to antibiotic chemotherapy directed at Mycobacterium tuberculosis. Ambroxol, a lead compound, emerged from a screen for autophagy-inducing drugs. At clinically relevant doses, ambroxol induced autophagy in vitro and in vivo and promoted mycobacterial killing in macrophages. Ambroxol also potentiated rifampin activity in a murine tuberculosis model.

Reappraisal of H2S/sulfide concentration in vertebrate blood and its potential significance in ischemic preconditioning and vascular signaling

2008 ◽  
Vol 294 (6) ◽  
pp. R1930-R1937 ◽  
Author(s):  
Nathan L. Whitfield ◽  
Edward L. Kreimier ◽  
Francys C. Verdial ◽  
Nini Skovgaard ◽  
Kenneth R. Olson
Keyword(s):  
Ischemic Preconditioning ◽  
Baseline Level ◽  
Venous Blood ◽  
Sulfide Concentration ◽  
Potential Significance ◽  
Aortic Blood ◽  
Total Sulfide ◽  
Series Of Experiments

Hydrogen sulfide (H2S) is rapidly emerging as a biologically significant signaling molecule. Studies published before 2000 report low or undetectable H2S (usually as total sulfide) levels in blood or plasma, whereas recent work has reported sulfide concentrations between 10 and 300 μM, suggesting it acts as a circulating signal. In the first series of experiments, we used a recently developed polarographic sensor to measure the baseline level of endogenous H2S gas and turnover of exogenous H2S gas in real time in blood from numerous animals, including lamprey, trout, mouse, rat, pig, and cow. We found that, contrary to recent reports, H2S gas was essentially undetectable (<100 nM total sulfide) in all animals. Furthermore, exogenous sulfide was rapidly removed from blood, plasma, or 5% bovine serum albumin in vitro and from intact trout in vivo. To determine if blood H2S could transiently increase, we measured oxygen-dependent H2S production by trout hearts in vitro and in vivo. H2S has been shown to mediate ischemic preconditioning (IPC) in mammals. IPC is present in trout and, unlike mammals, the trout myocardium obtains its oxygen from relatively hypoxic systemic venous blood. In vitro, myocardial H2S production was inversely related to Po2, whereas we failed to detect H2S in ventral aortic blood from either normoxic or hypoxic fish in vivo. These results provide an autocrine or paracrine mechanism for myocardial coupling of hypoxia to H2S in IPC, i.e., oxygen sensing, but they fail to provide any evidence that H2S signaling is mediated by the circulation.

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