STUDY OF ARTERIAL GLUCOSE METABOLIC ACTIVITY RELATIONSHIP WITH AORTIC STIFFNESS AND REGIONAL HETEROGENEITY USING PET-MRI

Research on the discovery of new drugs to treat bacterial biofilm infections has been a priority for biomedical and scientific communities. Actually, the sessile mode of growth accounts for more than 80% of human bacterial infections and displays increased resistance to antibiotics. To date, there are no drugs with total efficacy against biofilms and the treatment failure is a recurrent clinical situation. This lack of alternatives boosted up again the exploration of the pharmacological properties of health-promoting agents from natural origin. In this connection, the potential of phytotherapeutic agents for the treatment/prevention of complex infectious diseases, such as those that involve biofilm formation has been intensified[1]. In view of that, the main aim of the present study was to evaluate the activity of four phytochemicals bellowing to terpenoids class [cis-6-nonen-1-ol (CIS), citronellic acid (CITACID), citronellol (CITRO) and 3-7-dimethyl-1-octanol (3,7DOC)] against Staphylococcus aureus, both in planktonic and sessile state. Firstly, the minimum inhibitory and bactericidal concentrations (MIC and MBC) were determined by the broth microdilution method and culturability on plate count agar, respectively. Then, the potential of each terpenoid as resistance modifying agent was assessed by the disc diffusion method, using antibiotics from different classes. Besides, its potential to eradicate pre-formed S. aureus biofilms (24-h old) was performed using a microtiter plate assay and characterized in terms of biofilm mass removal (crystal violet staining), metabolic activity reduction (alamar blue staining) and culturability (colony forming units - CFU - counts). Considering that the selected terpenoids are chemical structurally related, i.e. present a similar backbone and differ only on the functional groups location, a structure activity relationship (SAR) analysis was also established. Both CITO and 3,7DOC presented the lowest MIC value (200 &#956;g/mL) followed by CIS (400 &#956;g/mL) and CITACID (1000 &#956;g/mL). The MBC was found to be 1000 &#181;g/mL with CIS, 2000 &#181;g/mL with CITACID and > 2000 &#181;g/mL (the maximum concentration tested) with CITO/3,7DOC. Apparently, the hydrophobicity of the molecules appear to affect positively its inhibitory proprieties &#8211; molecules with higher hydrophobicity presented lower MIC values. Moreover, it seems that the hydroxyl and methyl functional groups play the major influence on the antimicrobial properties. Indeed, CITO and 3,7DOC presented the higher hydrophobicity values and both had hydroxyl and methyl functional groups, possessing the lowest MIC value. Independently of the terpenoid tested, all combinations (terpenoid-antibiotic) resulted in a potentiation effect. Regarding biofilm eradication, although no biomass removal was observed, metabolic activity reductions from 25% (CIS at 5&#215;MIC) up to 44% (CITACID at 10&#215;MIC) and total loss of culturability (CITACID at 10&#215;MIC; 6-log CFU/cm2 reduction) was found. These effects were found to be dose dependent. Overall, the results obtained suggest that all the tested terpenoids might be interesting antibiotic adjuvants and emphasize the use of CITACID for biofilm cells inactivation. The results obtained are promising since the terpenoids studied are natural occurring flavoring ingredients, generally recognized as safe by the FDA, which are usually applied as food additives for human consumption. References: [1] A.Borges, A.Abreu, C.Dias, M.Saavedra, F.Borges, M.Sim&#245;es, Molecules 21(2016)877.

Download Full-text

Ultrastructure and Drug Metabolism in the Developing Guinea Pig

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100073131 ◽

1973 ◽

Vol 31 ◽

pp. 538-539

Author(s):

W. Kuenzig ◽

M. Boublik ◽

J.J. Kamm ◽

J.J. Burns

Keyword(s):

Guinea Pig ◽

Metabolic Activity ◽

Animal Species ◽

Adult Animal ◽

Smooth Endoplasmic Reticulum ◽

Fetal Life ◽

Mixed Function Oxidase ◽

Cytochrome P 450 ◽

Microsomal Mixed Function Oxidase ◽

Mixed Function Oxidase Activity

Unlike a variety of other animal species, such as the rabbit, mouse or rat, the guinea pig has a relatively long gestation period and is a more fully developed animal at birth. Kuenzig et al. reported that drug metabolic activity which increases very slowly during fetal life, increases rapidly after birth. Hepatocytes of a 3-day old neonate metabolize drugs and reduce cytochrome P-450 at a rate comparable to that observed in the adult animal. Moreover the administration of drugs like phenobarbital to pregnant guinea pigs increases the microsomal mixed function oxidase activity already in the fetus.Drug metabolic activity is, generally, localized within the smooth endoplasmic reticulum (SER) of the hepatocyte.

Download Full-text

Fibroblasts During Hypertrophic Scar Formation and Resolution

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072587 ◽

1973 ◽

Vol 31 ◽

pp. 428-429

Author(s):

C. W. Kischer

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Cell Proliferation ◽

Fine Structure ◽

Metabolic Activity ◽

Hypertrophic Scar ◽

Normal Skin ◽

Ground Substance ◽

Hypertrophic Scars ◽

Scanning Electron

The morphology of the fibroblasts changes markedly as the healing period from burn wounds progresses, through development of the hypertrophic scar, to resolution of the scar by a self-limiting process of maturation or therapeutic resolution. In addition, hypertrophic scars contain an increased cell proliferation largely made up of fibroblasts. This tremendous population of fibroblasts seems congruous with the abundance of collagen and ground substance. The fine structure of these cells should reflect some aspects of the metabolic activity necessary for production of the scar, and might presage the stage of maturation.A comparison of the fine structure of the fibroblasts from normal skin, different scar types, and granulation tissue has been made by transmission (TEM) and scanning electron microscopy (SEM).

Download Full-text

Ultrastructural aspects of gymnosperms reproductive organs tissues due to their functional condition

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083060 ◽

1978 ◽

Vol 36 (2) ◽

pp. 440-441

Author(s):

G. M. Kozubov

Keyword(s):

Metabolic Activity ◽

Functional Condition ◽

Reproductive Organs ◽

Considerable Change ◽

Complicated Structure ◽

Tetrad Stage ◽

Ubisch Bodies ◽

Similar Organization ◽

Female Reproductive Organs ◽

High Metabolic Activity

The ultrastructure of reproductive organs of pine, spruce, larch and ginkgo was investigated. It was found that the male reproductive organs possess similar organization. The most considerable change in the ultrastructure of the microsporocytes occur in meiosis. Sporoderm is being laid at the late tetrad stage. The cells of the male gameto-phyte are distinguished according to the metabolic activity of the or- ganells. They are most weakly developed in the spermiogenic cell. Ta-petum of the gymnosperms is of the periplasmodic - secretorial type. The Ubisch bodies which possess similar structure in the types investigated but are specific in details in different species are produced in tapetum.Parietal and subepidermal layers are distinguished for their high metabolic activity and are capable of the autonomous photosynthesis. Female reproductive organs differ more greatly in their struture and have the most complicated structure in primitive groups. On the first stages of their formation the inner cells of nucellus are transformed into the nucellar tapetum in which the structures similar to the Ubisch bodies taking part in the formation of the sporoderm of female gametophyte have been found.

Download Full-text