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At least 829 records · Page 46Linked to original sources
PubMed1978

[Changes in biogenic amines and connective tissue in the process of chemical carcinogenesis].

On two models of chemically induced tumors (cancer of the mammary gland and subcutaneous sarcoma) in rats the author has demonstrated the kinetics of biogenic amines transformations in the organism and their association with the developed structural-functional disorders in the connective tissue elements. It was found that the activity of connective tissue cells determined by the presence in them of such enzymes as nonspecific esterase, lipase and monoaminoxidase is directly dependent on the status of the intestinal enterochromaffin apparatus and the adrenal medulla and also on the presence of serotonin in connective tissue cells. The appearance of di-and polyamines in the pretumor period and their increase in the tumor period in conncective tissue noncellular structures indicate the enhancement of degeneration of these structures, while the presence of these substances in connective tissue cells evidences the suppression of their specific functions. It is believed that the source of production of di-and polyamines in the organism under tumor development is protein formations of noncellular structures of the connective tissue subjected to deorganization and destruction.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1998

Measurement of nitrite and nitrate in plasma, serum and urine of humans by high-performance liquid chromatography, the Griess assay, chemiluminescence and gas chromatography-mass spectrometry: interferences by biogenic amines and N(G)-nitro-L-arginine analogs.

In this paper, the HPLC method for the measurement of nitrite and nitrate in serum of humans newly reported by E1 Menyawi et al. is discussed, especially in regard to the extremely low nitrate levels measured in serum of healthy humans. From the discussion, it is concluded that: (1) Biogenic amines at physiological concentrations do not significantly interfere with the batch Griess assay. (2) The HPLC method of E1 Menyawi et al. does not reveal accurate levels for serum nitrate. (3) In serum and plasma of healthy humans, nitrate ranges within 15-70 microM. (4) Exogenous NG-nitro-L-arginine analogs can interfere with the measurement of nitrate in human plasma and urine by the batch Griess assay, chemiluminescence and GC-MS; interferences can be effectively eliminated by solid-phase extraction on cation-exchangers.

Artifacts↗
PubMed1976

Malignant APUDoma (carcinoid) of the anterior mediastinum. Simplified methods of demonstrating biogenic amines in endocrine neoplasms.

Endocrine neoplasms of the thymus and mediastinum are uncommon. This report describes such a carcinoma and the difficulty in determining its true nature. A simple modification of the technique for formaldehyde-fume-induced fluorescence (FIF) demonstrated biogenic amines in the cells. Electron microscopy and histochemical findings confirmed the close relationship of these neoplasms with neural-crest cells capable of amine precursor uptake and decarboxylation (APUD). The FIF technique is also a more sensitive method of detecting these tumors, since it has less of the sampling problems of electron microscopy, and the fluorescent granules are more easily seen than those stained by the usual methods. The techniques are simple enough for screening all poorly differentiated carcinomas in this area to determine a more accurate incidence figure.

Adult↗
PubMedDate not supplied

[Biogenic amines and the functional state of the liver in experimental allergic encephalomyelitis and postdiphtheritic polyneuritis in dogs].

Severity of paralytic syndrome correlated with impairments in some functions of liver tissue (bile secretion, concentrating and detoxicating capacities) as well as with content of biogenic amines, lactic and pyruvic acids in liver and in blood, flowing in and out the liver tissue in dogs with experimental allergic encephalomyelitis and with postdiphtheritic polyneuritis. The alterations observed were due to development of demyelinization in the nerves and to the effects of additional factors, caused by insufficiency in external respiration.

Amine Oxidase (Copper-Containing)↗
PubMedDate not supplied

[The characteristics of the effect of tuftsin on the behavior and on the level of biogenic amines in the brain of rats with differing resistance to acoustic stress].

The influence of tetrapeptide tuftsin (Tyr-Lys-Pro-Arg) on learning, exploratory activity, emotional behavior, and hypothalamic monoamine content was studied in Wistar rats with different resistance to stress induced by acoustic stimuli. Positive effects of taftsin were more pronounced in low-resistant rats. Administration of taftsin induced in these animals a significant increase in reactivity to stimuli of different modalities, the open-field exploratory activity, rate of alimentary conditioning and its modification in emotionally negative situation. Biochemical examinations showed that in rats with high resistance to stress taftsin administration led to a decrease in hypothalamic noradrenaline level and increase in dopamine and serotonin levels. On the contrary, in low-resistant animals taftsin increased the level of noradrenaline and decreased that of dopamine, serotonin, and 5-hydroxyindoleacetic acid. It is suggested that different behavioral effects of taftsin in stress-resistant and nonresistant rats are caused by its different influence on hypothalamic biogenic amines.

Acoustic Stimulation↗
PubMed1976

Effects of chronic exposure to cadmium, lead and mercury of brain biogenic amines in the rat.

Effects of chronic (45 days) treatment with different doses of cadmium chloride (0.25 and 1.0 mg/kg/day), methylmercury chloride (0.4 and 4.0 mg/kg/day) and lead acetate (0.2 and 1.0 mg/kg/day) and of 28-day withdrawal of treatment on the levels of acetylcholine (ACh) and activity of acetylcholinesterase (AChE) in cerebral cortex, and concentration of norepinephrine (NE) and 5-hydroxytryptamine (5-HT) in brain-stem were examined in rats. Exposure to both cadmium and methylmercury produced significant decreases in cortical ACh and brain-stem 5-HT levels. In addition, brain-stem NE concentration was increased in methylmercury-treated rats. In contrast, chronic treatment with lead resulted in enhanced cerebrocortical ACh levels but a decreased brain-stem NE concentration. Treatment with cadmium also produced a transient enhancement of striatal dopamine levels. Cadmium-induced decrease in brain-stem 5-HT and lead-induced accumulation of cortical ACh persisted even after 28 day withdrawal of treatment. The data indicate that chronic exposure to low doses of heavy metals produces differential changes in regional levels of various brain biogenic amines. These changes may represent the early signs of adverse effects on CNS function since they occur before any overt symptoms of neurotoxic effects of heavy metals become apparent.

Acetylcholine↗
PubMed2004

The effect of mutations altering biogenic amine metabolism in Drosophila on viability and the response to environmental stresses.

Dopamine (DA) content, tyrosine decarboxylase (TDC) activity and survival were studied under normal and environmental stress conditions in the ste and e strains carrying ebony mutation increasing DA level and the octopamineless strain Tbetah(nM18) of Drosophila melanogaster. Wild-type strains Canton S and Oregon R, and strain p845 from which Tbetah(nM18) strain was derived were used as controls. Sexual dimorphism of TDC activity, DA content, and survival in flies of all D. melanogaster strains under study was found. Tbetah(nM18) mutation sharply reduced TDC activity in females, while ebony had no such effect. DA content and survival under heat stress in Tbetah(nM18) flies did not differ from those in the wild type. ste and e flies had drastically increased DA content under normal conditions, dramatically decreased survival under heat stress, but increased survival under starvation. DA content and survival under heat stress were also studied in the reciprocal hybrids (males) F(1) of the cross D. virilis strains 101 (wild type) and 147 with X-linked mutation, which significantly increases DA content. 147x101 males had a considerably higher DA content and lower survival than 101x147 ones. Individuals of all D. melanogaster strains under study developed the stress reaction, as judged by changes in TDC activity and DA levels. The role of biogenic amines in the stress reaction development and adaptation to environmental stresses in Drosophila is discussed. Arch. Insect Biochem. Physiol. 55:55-67, 2004.

Adaptation, Physiological↗
PubMed2001

The influence of three months of methylphenidate treatment on platelet-poor plasma biogenic amine levels in boys with attention deficit hyperactivity disorder.

Attention deficit hyperactivity disorder (ADHD) is related to dysregulation in the activity of brain monoamines. The aim of the present study was to assess the impact of three months' methylphenidate (MPH) treatment on platelet-poor plasma (PPP) norepinephrine (NE), dopa and serotonin (5-HT) levels as well as on ADHD symptomatology. Three months of MPH treatment in 16 ADHD boys, aged 11.4 +/- 1.6 years, resulted in a significant reduction in PPP NE levels (p < 0.05). A tendency towards a reduction of PPP 5-HT and dopa levels was detected (p < 0.1 for both). The decrease in PPP biogenic amine levels after three months of MPH treatment was accompanied by a significant reduction in all psychometric characteristics of ADHD. This result indicates the possible role of overactivity of the noradrenergic system in the pathophysiology of ADHD and suggests that the MPH therapeutic action may be related to stimulant-induced inhibitory effect on the noradrenergic system. Copyright 2001 John Wiley & Sons, Ltd.

Journal Article↗
PubMed2025

Biogenic Synthesis and Characterization of Hypecoum pendulum Mediated Silver Nanoparticles: Revealed Outstanding Anticancer and Genotoxic Potentials.

Fabrication of silver nanoparticles by green approach is the most effective and eco-friendly technique in recent technologies. The current study aimed to generate a simple, valid, and justifiable method for biogenic synthesis of silver nanoparticles (HP-AgNPs) using aqueous extract of Hypecoum pendulum L.(HP) and to assess their in&#xa0;vitro anticancer and genotoxic potentials on baby hamster kidney cell (BHK-21) and human blood lymphocytes using 3-(4,5-dimethylthiazol-2-yl-)-2,5-di-phenyltetrazolium bromide (MTT) and alkaline comet assay, respectively. HP-AgNP characterization was done using UV-vis spectrometry, EDX, SEM, XRD, and FTIR techniques. The crystalline nature of HP-AgNPs with a particle size of 36.3&#x2009;nm was assessed using the XRD technique. The surface morphologies with a particle size of 80&#x2009;nm were verified by SEM analysis. UV spectroscopy verified the existence of HP-AgNPs by yielding a sharp peak at 417&#x2009;nm with an absorbance intensity of 1.54. FTIR assessment revealed the existence of different functional moieties that contribute to the HP-AgNPs stabilization and reduction. Similarly, EDX analysis revealed Ag as a principal element (49%). MTT assay showed significant cytotoxicity by Doxorubicin and HP-AgNPs with a smaller IC50 value of 104.21&#x2009;&#xb1;&#x2009;4.33 and 134.91&#x2009;&#xb1;&#x2009;6.33&#x2009;&#x3bc;g/mL correlated to HP extract (229.84&#x2009;&#xb1;&#x2009;4.66&#x2009;&#x3bc;g/mL). The outcomes of the comet assay revealed potential DNA damage in a positive trend with concentration (25-600&#x2009;&#x3bc;g/mL). HP-AgNP-treated lymphocytes showed higher DNA damage as compared to HP extract-treated cells, but less damage as compared to a positive control, H2O2. These outcomes showed that HP-AgNPs have demonstrated promising anticancer and genotoxic action than HP extract due to their size and shape.

Silver↗
PubMed1979

High-performance liquid chromatographic studies of reaction of hydralazine with biogenic aldehydes and ketones.

To understand hydrazone formation in hydralazine metabolism, the reaction of hydralazine with various biogenic aldehydes and ketones (acetone, pyruvic acid, acetoacetic acid, formaldehyde, and acetaldehyde) in pH 7.4 buffer was studied for potential alterations in hydralazine pharmacokinetics secondary to alcoholism and diabetes. The corresponding hydrazones were isolated, and their structures were characterized. High-performance liquid chromatography was used to monitor the reactions. An aqueous solvent reversed-phase liquid chromatographic system was used to separate hydralazine and its derivatives. Reaction of hydralazine with formaldehyde or acetaldehyde produced the corresponding hydrazones. Formation of an s-triazolo ring system yielded the known s-triazolo[3,4-alpha]phthalazine and 3-methyl-s-triazolo[3,4-alpha]phthalazine metabolites, which also were isolated and characterized and suggested nonenzymatic metabolism.

Aldehydes↗
PubMed1996

DNA triple helix stabilization by bisguanidinyl analogues of biogenic polyamines.

The polycationic nature of biogenic polyamines such as spermine (SPM, 1) and spermidine (SPD, 2) plays an important role in selective binding to polyanionic nucleic acids. These interactions are mediated by electrostatic and hydrogen bonding forces which led to stabilization of DNA duplexes and triplexes. Transformation of primary amino groups in these molecules into corresponding guanidinium functions is expected to amplify the electrostatic component resulting in improved binding. An easy chemical transformation route as described here gives rise to bisguanidinated derivatives of spermine (SPMG, 3) and spermidine (SPDG, 4). Both enhances DNA duplex stability over the parent polyamines whereas SPMG is more selective for stabilization of DNA triplexes even at pH 7.0. The results have implication for designing of new DNA binding ligands.

Base Sequence↗
PubMed1988

Differential distribution of biogenic amines in the hypoglossal nucleus of the rat.

The distribution of biogenic amines in the rat hypoglossal nucleus (nXII) was investigated with immunocytochemical methods using antibodies to tyrosine hydroxylase (TH) as a marker for catecholamines, and to 5-hydroxytryptamine (5-HT), the principal indoleamine, at the light microscopic level. TH and 5-HT immunoreactivity were found throughout all regions of nXII. Although the innervations overlapped, clearly different patterns of distribution were observed. TH immunoreactivity was localized primarily in the ventromedial quadrant of the caudal half of nXII and appeared largely as perisomatic-like profiles. In contrast, 5-HT immunoreactivity was greatest dorsally along the caudal half of nXII, although secondary foci of staining were evident ventrolaterally and, to a lesser extent, ventromedially. A perisomatic-like pattern of termination was observed for 5-HT in both dorsal and ventral regions of nXII. Since ventral and dorsal districts of nXII contain motoneurons that innervate protrusor and retrusor tongue muscles, respectively, we propose that the overlapping, yet differential distributions of catecholamines and indoleamines are important in controlling the relationships between functionally related groups of nXII motoneurons. These findings are discussed in relation to oro-lingual motor dysfunction.

Animals↗
PubMed1977

[A contribution to the distinction of biogenic vinegar and vinegar made from synthetic acetic acid by determining the specific 14C-radioactivity (author's transl)].

The method of Simon et al. [2] for the separation of the acetic acid from vinegar prior to the determination of the specific 14C-radioactivity has been modified. The precipitation as calcium acetate and the preparation of free acetic acid by addition of diphosphoric acid has been replaced by an extraction procedure with diisopropylether which is faster and cheaper. On the Austrian market glacial acetic acid (Merck, p.A.) having the natural spezific 14C-radioactitivity was found. The natural specific 14C-radioactivity is therfore necessary but not sufficient to prove the biogenic origin of vinegar.

Acetates↗
PubMed1996

Depression in Parkinson's disease: biogenic amines in CSF of "de novo" patients.

INTRODUCTION: Etiology of depression in Parkinson's disease (PD) is associated with serotonergic dysfunction. Previous studies, supporting this hypothesis, were performed on patients treated with antiparkinsonian drugs. To eliminate the influence of parkinsonian drug therapy and to elucidate significance of different biochemical pathways in PD associated with depression we determined levels of biogenic amines in cerebrospinal fluid (CSF) of 26 untreated "de novo" Parkinsonian patients. MATERIAL AND METHODS: Patients were scored with the Hamilton depression scale (HD) and subdivided into groups with HD score > or = 18 and HD score < 18. Diagnosis of depression was made according to DSM III R. Both groups were matched for age and motor disability. RESULTS: In both groups no significant differences appeared between CSF levels of dopamine, noradrenaline, 3,4-dihydroxyphenylacetic acid, homovanillic acid, 3-methoxy-4-hydroxyphenylglycol and 5-hydroxyindole acetic acid, determined by high-performance liquid chromatography. DISCUSSION: In contrast to previous studies on treated Parkinsonian patients no sign of altered serotonin metabolism especially in context with severity of depression in early stages of PD was found. Due to our results, we suggest, that biochemical markers of depression in CSF of PD may be influenced by antiparkinsonian therapy and that depression in PD may respond to serotonin reuptake inhibitors mainly in later stages of PD.

Aged↗
PubMed2004

A direct quantitative analysis method for monitoring biogenic volatile organic compounds released from leaves of Pelargonium hortorum in situ.

A direct quantitative method is presented that is based upon the use of multiple headspace solid phase microextraction (HS-SPME) to monitor biogenic volatile organic compounds (BVOCs) released from a living leaf of Pelargonium hortorum in situ. Seventeen BVOCs were detected by GC-MS after a single SPME extraction using a CAR/DVB/PDMS fibre. An internal standard was employed to determine the absolute amounts of seven terpenoid compounds released from a P. hortorum leaf. The quantitative analysis was performed over two days, with extraction preformed for 20 min every 3 h. The amount of volatiles extracted varied with the time of day, with two maxima recorded at 14:00 (day 1) and 17:00 (day 2), corresponding to 236 and 277 ng of the seven terpenoids recorded, respectively. These results indicate that multiple HS-SPME in combination with an internal standard is a simple, quick, and quantitative technique for analysising BVOC emissions from a live plant sample.

Calibration↗
PubMed2006

Development of a supercritical fluid extraction-gas chromatography-mass spectrometry method for the identification of highly polar compounds in secondary organic aerosols formed from biogenic hydrocarbons in smog chamber experiments.

A new one-step method for the analysis of highly polar components of secondary organic aerosols (SOA) has been developed. This method should lead to a better understanding of SOA formation and evolution since it enables the compounds responsible for SOA formation to be identified. Since it is based on supercritical fluid extraction coupled to gas chromatography-mass spectrometry, it minimizes the analysis time and significantly enhances sensitivity, which makes it suitable for trace-level compounds, which are constituents of SOA. One of the key features of this method is the in situ derivatisation step: an online silylation allowing the measurement of highly polar, polyfunctional compounds, which is a prerequisite for the elucidation of chemical mechanisms. This paper presents the development of this analytical method and highlights its ability to address this major atmospheric issue through the analysis of SOA formed from the ozonolysis of a biogenic hydrocarbon (sabinene). Ozonolysis of sabinene was performed in a 6 m3 Teflon chamber. The aerosol components were derivatised in situ. More than thirty products, such as sabinaketone, sabinic acid and other multifunctional compounds including dicarboxylic acids and oxoacids, were measured. Nine of them were identified and quantified. The sensitivity and the linearity (0.91<R<0.98) of the method were both good and detection limits ranged from 1.2 to 6.4 ng for the investigated compounds.

Aerosols↗
PubMed2002

Investigation of age-related variations in biogenic magnetite levels in the human hippocampus.

The magnetic properties of human hippocampal tissue from 23 subjects (15 epilepsy patients and eight cadavers with no neuropathology) were analysed and tissue concentrations of magnetic material were calculated. The biogenic iron oxide magnetite (Fe(3)O(4)) is the dominant source of magnetisation in the tissue. Analysis of the group as a whole revealed no significant trend towards either increasing or decreasing magnetite concentration with age. Separate analysis of male and female subjects, however, reveals a trend towards increasing magnetite concentration with age in males. This trend is not seen in females and may have implications for iron metabolism and neurological disorders associated with disruptions in normal iron homeostasis.

Adolescent↗