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PubMedDate not supplied

Biogenic amines in human gingiva in healthy and inflamed states.

As inflammatory disturbance are of significance in every aspect of periodontal disease, it was deemed pertinent to conceive on experimental study exploring the existence and relationship of biogenic amines, at least in the inflammatory gingiva. Gingival samples from 50 human individuals representing varying grades of inflammatory involvement have been utilised in the present work. From the results of this study, it could be elucidated that biogenic amines (noradrenaline, dopamine and 5-hydroxytryptamine) should show elevated concentration in inflammatory states of the gingiva. Further, these amines turnover was confirmed by studying monoamine oxidase which is a catalyzing enzyme of noradrenaline and 5-hydroxytryptamine; and 5-hydroxy indole aceticacid is a metabolic end product of 5-hydroxytryptamine. This was of a transitory nature indicating increased levels at the early stages of inflammation followed by a decrease at the peak of the gingival inflammation. It is assumed that biogenic amines helps in regeneration of connective tissue of the oral mucosa during the initial development of inflammation rather than final stages of the process, thereby emphasizing its transitory role in the inflammatory process.

Adult↗
PubMed1989

[Changes in the balance of biogenic monoamines and their metabolites in the organs of rats with oxygen-induced epilepsy].

The content of some biogenic monoamines and their metabolites in rat brain and heart in different periods of oxygen epilepsia was studied using high performance liquid chromatography with electrochemical detection. It was shown that already at the 5th minute of exposure to oxygen adrenaline, DOPA and some noradrenaline metabolites disappeared in the brain and noradrenaline level reduced. At this period in rat heart the reduction of catecholamine content was the most distinct and serotonin level was unchanged. At the beginning of convulsive period the modifications of biogenic amines content were nonparallel in brain regions: in the heart the reduction of catecholamine level went on, especially in right ventricle. In the terminal phase of oxygen epilepsia brain biogenic amines increased, however, not up to normal meaning, heart catecholamines at this period were at the same level as at the beginning of the convulsive period.

Animals↗
PubMedDate not supplied

[Participation of the lungs in the absorption and liberation of biogenic amines in the postresuscitation period].

After revival from a 10-minute clinical death caused by acute blood loss the transport of biogenic amines to the lungs in dogs did not increase for 3 hours. Their absorption by the lungs was replaced periodically by their liberation; both processes were intensified for serotonin but weakened for histamine. In 6-9 hours during the period of hypoperfusion and reduction of the transport of amines to the lungs the intensity of absorption and liberation of serotonin by the lungs were normalized, while these processes for histamine remained diminished. The content of biogenic amines in arterial blood reduced. Twenty-four hours later, under conditions of normalization of hemodynamics, the transport of histamine to the lungs and its concentration in blood were still reduced, while the transport and absorption of serotonin by the lungs, as well as its content in arterial blood, increased; this was attended by an increase in total pulmonary resistance and the development of moderate hypoxemia. Animals who died subsequently had a higher level of serotonin in arterial blood but a lower level of histamine. The role of the lungs in homeostasis of blood biogenic amines in the postresuscitation period is discussed.

Animals↗
PubMed1987

[Synthesis and binding characteristics of an artificial receptor for biogenic amines].

The synthesis of a ditopic linear receptor 3 consisting of an azacrown ether moiety for binding prim. ammonium functions and a macrotricyclic tetrahedral moiety for binding hydrophobic guest species is described. The covalent interconnection of these subunits was supposed to constitute a receptor with enhanced specificity towards dopamine-type biogenic amines. Host-guest complexation was studied in a competition method with potassium ion using ion selective electrodes. The binding features of 3 with a series of biogenic amines reveal that neither the absolute binding strength nor the selectivity is enhanced in relation to the monotopic receptor 4. It is concluded that 3 does not simultaneously utilize both receptor subunits in binding the biogenic amine substrates.

Biogenic Amines↗
PubMed1986

Topographic aspects of prostacyclin-like and fibrinolytic activity and of biogenic amines in the arterial system of the mini-pig.

Although arteriosclerosis is a systemic disease, it nevertheless exhibits noticeable topographical preference and particularities. The reason for this could be lie with certain biochemical features of the arterial wall. We therefore examined prostacyclin-like and fibrinolytic activity in mini-pigs, as well as the concentration of various biogenic amines in the thoracic and abdominal aorta, in coronary arteries and in the carotid and femoral artery. There was a similar behaviour between PG I2-like release and biogenic amines in the different arteries, whereas fibrinolytic activity behaved differently in some cases. In the femoral artery particularly low fibrinolytic activity was confronted by a particularly high level of PG I2-like activity and biogenic amines, while the reverse was the case in the abdominal aorta. In older animals PG I2-like activity considerably decreased.

Animals↗
PubMed1987

Entrance of tetrahydropterin derivatives in brain after peripheral administration: effect on biogenic amine metabolism.

The ability of various structural analogs of tetrahydrobiopterin to enter the rat brain and remain in the reduced form after i.p. administration was tested because tetrahydrobiopterin itself enters poorly. The total content of various pterins in different brain areas was measured by high-pressure liquid chromatography-fluorescence detection, whereas high-pressure liquid chromatography-electrochemical detection was used to measure the content of reduced pterins. The effect of injection of certain tetrahydropterins on brain content of biogenic amines and their major metabolites was also monitored. In general, when the position 6 side-chain of tetrahydrobiopterin was made shorter and smaller in size, entrance into the brain from the periphery was markedly enhanced. Increasing the lipophilicity or size of the position 6 side-chain did not allow for better entry into brain and, in some cases, hindered entry. Under the conditions tested, none of the tetrahydropterins influenced the brain content of biogenic amines or their major metabolites; higher brain concentrations of tetrahydropterins are probably necessary to modify central nervous system biogenic amine metabolism. Other types of structural modifications or experimental approaches may be necessary to achieve higher brain concentrations of active cofactors, which may be required for the successful treatment of certain human diseases with tetrahydropterins.

Animals↗
PubMedDate not supplied

[Status of biogenic amine metabolism in tumors of chiasm-sellar localization].

Histamine, serotonin, and catecholamine metabolism was studied in 47 patients with tumors of diencephalic localization. It was shown that the degree of involvement of the hypothalamus in the tumor determined the different character of metabolic changes of biogenous amines. Three stages of biogenous amine metabolism were distinguished: activation, compensation, and exhaustion. The degree of metabolic changes manifestation before the operation determined to a great measure the organism's reaction to it. The work substantiates the necessity for taking into consideration the metabolism of biogenous amines before undertaking surgery.

Biogenic Amines↗
PubMed1975

[Methods of the histochemical detection of biogenic amines (author's transl)].

Histochemical and ultrahistochemical methods for the demonstration of biogenic amines are investigated with regard to their efficiencies and limitations. For the purposes of the light microscopy fluorescent histochemical methods at present are sufficient. Hereby beta-arylethyl-amines and indolalkylamines are demonstrable with formaldehyde or glyoxylic acid whilst histamine is traceable with o-phthaldialdehyde. In this connection those chemical and physical conditions of this methods are shown, under which the demarcation and quantitative determination of the several amines is possible. Ultrahistochemically biogenic amines can be demonstrated by means of the chromaffine and the argentaffine reaction, the reaction with permanganate and the REINECKE-salt precipitation technique. Apart from the latter one, all these methods are based on an initially reaction between glutaraldehyde and amines. Thus these techniques might be founded on one and the same principle. Besides, the demonstration of adreanline as a secondary amine might be hindered also by the fact that the product of its reaction with glutaraldehyde is soluble in water. On the other hand the reaction product of primary amines with glutaraldehyde is insoluble in water. When using REINECKE-salt the correctly localizated precipitation of amines is the first step of the reaction. After that the treatment with glutaraldehyde is only serving for the fixation of the tissues. But the ultrahistochemical methods mentioned above altogether are showing a deficiency as far as they do not allow to make the several amines selectively visible. Therefore a quantitative ultrahistochemistry of biogenic amines is still impossible at present.

Biogenic Amines↗
PubMedDate not supplied

[Isoniazid distribution and biogenic amine metabolism in brain structures].

The effect of isoniazid (200 mg/kg) on metabolism of biogenic amines in different parts of the brain was studied in acute experiments on white rats. Isoniazid was detected in all test organs one hour after the administration, with metabolism of biogenic amines changed. The level of biogenic amines is related not only to the drug distribution pattern but also to the specificity of its participation in the biochemical processes, restricting the synthesis of monoamines.

Animals↗
PubMedDate not supplied

[Biogenic amine metabolism in severe brain trauma during various techniques of brain protection from hypoxia].

Biogenic amine metabolism in severe brain trauma has been analysed in 165 patients whose brain was protected from hypoxia with GOBA and thiobarbiturates in subnarcotic doses (116 cases) and the combination of the above agents with an early course of HBO (49 cases). The peculiarities of biogenic amine metabolism have been established in patients recovered and those who died later. As any activation of biogenic amine systems realizing stress enhances disadaptation processes, it is recommended to begin a course of HBO upon their stabilization.

Adolescent↗
PubMedDate not supplied

Determination of biogenic amines in cheese.

A liquid chromatographic (LC) procedure for determining 10 biogenic amines in cheese is described. The method is based on ion-pair chromatography on a reversed-phase column with postcolumn derivatization with o-phthaldialdehyde and fluorometric detection. It allowed simultaneous determination of 10 amines in < 80 min: histamine, tyramine, tryptamine, 2-phenylethylamine, serotonin, agmatine, spermine, spermidine, putrescine, and cadaverine. Linearity for each amine was observed between 0.5 and 6.0 micrograms/mL. Detection limits ranged form 0.004 to 0.009 micrograms/20 microL, and determination limits ranged from 0.066 to 0.149 mg/100 g. Amino acids and other amines did not interfere with determination of biogenic amines. Three extractants--methanol, hydrochloric acid, and trichloroacetic acid--were compared in their efficiency to recover amines from spiked samples. Purification of the cheese extract was required prior to LC to avoid interference from compounds in the cheese matrix. Hydrochloric acid extraction followed by purification with diethyl ether gave best recoveries for all the amines (75.5-112.3%). The method is simple, fast, and reliable. It can be used to study the technological and toxicological implications of biogenic amines in cheeses.

Biogenic Amines↗
PubMed1999

Experimental calibration and field investigation of the oxygen isotopic fractionation between biogenic aragonite and water.

Marine molluscs have long been recognised as potential records of palaeoclimate change using the patterns and differences in the stable isotopic composition of the carbonate shells. The aim of this study is to improve the robustness of this approach for aragonitic molluscs by completing the first experimental calibration of the fractionation between water and biogenic aragonite. Fractionation factors were calibrated by growing specimens of the freshwater mollusc Lymnaea peregra under controlled conditions of water temperature and isotopic composition. Fifteen populations of L. peregra were maintained at constant temperature and isotopic conditions for five months (at five different temperatures and using three different water compositions). Water samples and temperature measurements were taken regularly throughout the experiment. The temperature dependence of the fractionation factor, between 8 and 24 degrees C, is given by: 1000 ln alpha=16.74x(1000T(-1))-26.39 (T in Kelvin) and the relationship between temperature (T), delta(18)O(carb) and delta(18)O(wat) is given by: T=21.36-4.83xdelta(+ degrees )O(carb)-delta(+ degrees )O(wat) (T is in degrees C, delta(18)O(carb) is with respect to Vienna Pee Dee Belemnite (PDB), the International Atomic Energy Agency (IAEA) replacement standard for PDB, and delta(18)O(wat) is with respect to Vienna standard mean ocean water (VSMOW)) The outcome of the controlled experiment is compared with previous studies on synthetic, and biogenic, calcite and aragonite from field and laboratory investigations. These comparisons suggest that although a vital offset exists between the fractionation of isotopes in synthetic and biogenic aragonite for molluscs in general, there is no vital effect that is specific either to freshwater, or to individual, genera. Therefore, the calibrated relationship may be used for any freshwater or marine mollusc to derive palaeotemperatures providing the isotopic composition of the environmental water can be reliably constrained. Copyright 1999 John Wiley & Sons, Ltd.

Journal Article↗
PubMed1986

Structural aspects of biogenic silica.

The objectives of this paper are to discuss the characterization of biogenic silica in terms of structural properties, and to elucidate the mechanisms of structural organization within biological systems. The scale of organization is a critical factor in the characterization of biosilicification processes, and order at the nanometre, micrometre and macroscopic levels is described. Molecular order is discussed in the light of high-resolution transmission electron microscopy and solid-state NMR results obtained from samples of biogenic silica. Microscopic organization is expressed in a range of structural motifs, e.g. gels, sheets, fibres, tubes and globular assemblies, and reflects the infinitely adaptive morphology of biogenic silica. Macroscopic structures such as curved rods, spicules, perforated plates, teeth and reticular frameworks can be assembled from these microscopic motifs. The mechanisms of structural organization involve spatial (scalar and vectorial) constraints, ordered particle aggregation and chemical regulation. The possible importance of organic surfaces is discussed.

Eukaryota↗
PubMed2001

Current perspectives on the development of non-biogenic amine-based antidepressants.

Compounds that inhibit the re-uptake and/or metabolism of biogenic amines (i.e. serotonin, norepinephrine, and dopamine) have been used to treat depression for more than 40 years. Selective re-uptake inhibitors, currently the most widely prescribed class of biogenic amine-based agents, are certainly safe and relatively easy to use, but do not exhibit either a faster onset of action or greater efficacy than their predecessors. An approach to overcome the limitations that may be inherent to these 'conventional' therapies is to circumvent the monoaminergic synapse. In this review, two potential antidepressant strategies are discussed that may converge with intracellular pathways impacted by chronic treatment with biogenic amine-based agents. Drugs emerging from these strategies may offer significant advantages over currently used antidepressants.

Animals↗
PubMed1993

Abnormalities of biogenic amine metabolism.

The term biogenic amine is an umbrella term that encompasses all amines with an origin in biological processes. This review will be restricted to the biogenic amine abnormalities that affect the metabolism of serotonin and the catecholamines. The synthesis and catabolism of these neurotransmitters are outlined, and a summary is given of the neurological details, biochemical features, and treatment of the inborn errors that primarily affect their metabolism. An idea is also developed that proposes that abnormalities of biogenic amine metabolism are far more common than is currently considered, and that the search for these problems may be appropriate in any neonate or infant who presents with neurological problems of unknown origin.

Biopterins↗
PubMed1983

Psychometric differentiation of biogenic and psychogenic impotence.

In a sequential clinical sample of 64 subjects exclusively diagnosed as either biogenically or functionally impotent, Minnesota Multiphasic Personality Inventory (MMPI) and California Psychological Inventory (CPI) standard scales and the Beutler, et al., MMPI signs were all found to be ineffective in reliably classifying patients into the correct diagnostic groupings. Specific item analysis of the MMPI and CPI did identify a significant number of significantly differentiating individual items. Most of these items were shown to be reliably characterizable as indicating either performance anxiety or somatic complaint. Using these classifications of the items, the performance anxiety items were shown, consistent with theory, to be clearly associated with the functional impotence group. The somatic complaint items were shown to be clearly associated with the biogenic impotence group, presumably reflecting the symptoms of physiopathology, such as diabetes, underlying the biogenic condition.

Diagnosis, Differential↗
PubMed2004

Exploitation of marine algae: biogenic compounds for potential antifouling applications.

Marine algae are one of the largest producers of biomass in the marine environment. They produce a wide variety of chemically active metabolites in their surroundings, potentially as an aid to protect themselves against other settling organisms. These active metabolites, also known as biogenic compounds, produced by several species of marine macro- and micro-algae, have antibacterial, antialgal, antimacrofouling and antifungal properties, which are effective in the prevention of biofouling, and have other likely uses, e.g. in therapeutics. The isolated substances with potent antifouling activity belong to groups of fatty acids, lipopeptides, amides, alkaloids, terpenoids, lactones, pyrroles and steroids. These biogenic compounds have the potential to be produced commercially using metabolic engineering techniques. Therefore, isolation of biogenic compounds and determination of their structure could provide leads for future development of, for example, environmentally friendly antifouling paints. This paper mainly discusses the successes of such research, and the future applications in the context of understanding the systems biology of micro-algae and cyanobacteria.

Animals↗
PubMed2003

Can the presence of structural phosphorus help to discriminate between abiogenic and biogenic magnetites?

The influence of phosphate on the competitive formation of magnetite and lepidocrocite and the properties of magnetite prepared from mixtures of Fe(II) and Fe(III) salts were studied. Products were prepared at 90 degrees C and pH 12.5 (series 1), 50 degrees C and pH 7 (series 2) and 20 degrees C and pH 8 (series 3). The P/Fe atomic ratio in the initial solution ranged from 0 to 3% and the pH was kept at the desired value with NaOH or KOH. Air was used as oxidant in series 2 and 3. All products, which were characterized by X-ray diffraction, transmission electron microscopy, chemical analysis and IR spectroscopy, contained a phase intermediate between magnetite and maghemite (referred to as magnetite in this paper). The products of series 1 consisted only of magnetite at all P/Fe ratios, whereas both magnetite and lepidocrocite formed in series 2 and 3 above a certain P/Fe ratio. On increasing the P/Fe ratio in the initial solution, the magnetite crystals became smaller and more oxidized (i.e. closer to maghemite) and the lepidocrocite/magnetite ratio increased. The P associated with magnetite was partly in the form of occluded P, i.e. non-surface-adsorbed phosphate. IR spectra suggested this P to be structural and occurring as low-symmetry PO(4) units. Because abiogenic magnetites produced in various environments incorporate structural P but some well-characterized biogenic magnetites seem to contain no P or be formed in P-poor environments, we hypothesize that natural magnetites containing occluded P are unlikely to be biogenic. However, more studies are needed to discard the presence of P in biogenic magnetites.

Ferrosoferric Oxide↗