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PubMed1979

Fate of vasoactive biogenic amines and activity of enzyme phenylethanolamine-N-methyltransferase in rat adrenal gland during the course of pregnancy, parturition and postpartum.

Influence of pregnancy, parturition and postparturition upon natural evolution of adrenaline, dopamine and enzyme of adrenaline synthesis, phenylethanolamine-N-methyltransferase in the adrenal gland was studied. Adrenaline content of the adrenal gland showed a progressive decrease from the 14th to the 18th day postcoitum. The mean values for adrenaline remained lower than the value of day 14 throughout the course of pregnancy up to day 21 postcoitum. At parturition (0 to 4 h) adrenaline declined again to its minimum value but was accompanied by an increase in the adrenal adrenaline level 24 h postpartum. The activity of enzyme phenylethanolamine-N-methyltransferase followed a similar pattern of evolution as that of adrenaline during pregnancy and postpartum. Dopamine concentration of the adrenal gland showed nonsignificant increases during days 14--18 postcoitum. At day 20 postcoitum adrenal dopamine was decreased to its minimum value and this decrease persisted up to day 21 postcoitum. At day 22 postcoitum, adrenal dopamine increased sharply to its maximum value but was again back to the level of day 21 at 0 h parturition. At 24 h postpartum, dopamine content decreased maximally again. The results presented here suggest that the content of vasoactive biogenic amines and the enzyme of adrenaline synthesis go through important natural variations during pregnancy, parturition and postpartum from day 14 postcoitum to 24 h postpartum. This phenomenon does not seem to be merely a cyclic effect. All these variations can be attributed to modified endocrine activity of the pregnant animals by correlating natural variations in steroid hormone levels with the observed changes in biogenic amines, since it is well established that most of the hormonal and nonhormonal steroids affect catecholamine regulation. The observed changes in amine levels could have important influence for the termination of pregnancy.

Adrenal Glands↗
PubMed2004

Comparison of different biogenic matrices seeded with cultured Schwann cells for bridging peripheral nerve defects.

Tissue-engineering as laboratory based alternative to human autografts and allografts provides "custom made organs" cultured from patient's material. To overcome the limited donor nerve availability different biologic nerve grafts were engineered in a rat sciatic nerve model: cultured isogenic Schwann cells were implanted into acellular autologous matrices: veins, muscles, nerves, and epineurium tubes. Autologous nerve grafts, and the respective biogenic material without Schwann cells served as control. After 6 weeks regeneration was assessed clinically, histologically and morphometrically. The PCR analysis showed that the implanted Schwann cells remain within all the grafts. A good regeneration was noted in the muscle-Schwann cell-group, while regeneration quality in the other groups (with or without Schwann cells) was impaired. The muscle-Schwann cell graft showed a systematic and organized regeneration including a proper orientation of regenerated fibers. All venous and epineurium grafts had a more disorganized regeneration. Seemingly, the lack of endoneural tube like structures in vein grafts lead to impaired regeneration. And, apparently, the beneficial effects of implanted Schwann cells into a large luminal structure can only be demonstrated to a limited extent if endoneural like structures are lacking. A tube offers less area for Schwann cell adhesion and it is more likely to collapse. This underlines the role of the basal lamina, or at least an inner structure acting as scaffold in axonal regeneration. Although the conventional nerve graft remains the gold standard, the implantation of Schwann cells into an acellular muscle provides a biogenic graft with basal lamina tubes as pathway for regenerating axons and the positive effects of Schwann cells producing neurotrophic and neurotropic factors, and thus, supporting axonal regeneration.

Animals↗
PubMed1994

Modulating a modulator: biogenic amines at subthreshold levels potentiate peptide-mediated cardioexcitation of the heart of the tobacco hawkmoth Manduca sexta.

The central nervous system of the moth Manduca sexta contains a group of myoregulatory neuropeptides, the CAPs (Cardioacceleratory Peptides), which cause a physiologically important, dose-dependent increase in heart rate during wing inflation and flight in adult moths. We report here that the response of the adult heart to a subset of the CAPs, the CAP2S, is potentiated nearly twofold in the chronic presence of subthreshold levels of the biogenic amine octopamine or near-threshold levels of the biogenic amine serotonin. Subthreshold levels of the CAP2S fail to alter the response of the heart to octopamine. We have begun to investigate the molecular mechanisms underlying this potentiation. Previous work on the adult heart has shown that the CAP2s act through an inositol-1,4,5-trisphosphate second-messenger system. Here, we demonstrate that the cardioexcitatory effects of the two amines, in contrast to those of the CAP2S, are both mediated by cyclic AMP. Application to the heart of either 10(-5) moll-1 octopamine or 10(-6)moll-1 serotonin elicits a threefold increase in intracellular cyclic AMP levels. The CAP2S have no effect on cyclic AMP levels in the heart. These results illustrate a mechanism by which the effectiveness of a neurohormone can be increased with minimal cost to the animal. In Manduca sexta, subthreshold levels of octopamine are found in the haemolymph during wing inflation and flight. Thus, it is possible that octopamine up-regulates the effects of CAP2 via a cyclic-AMP-dependent mechanism during these activities.

Animals↗
PubMed1987

Biogenic amine regulation of bovine luteal progesterone production in vivo.

Biogenic amines were administered using osmotic pumps placed subcutaneously in the neck region of regularly cycling, non-lactating dairy cows on Days 9-11 (oestrus = Day 0) of the oestrous cycle. Blood samples were collected using indwelling jugular catheters and the plasma progesterone concentrations were measured. Samples were collected at 4-h intervals for the first 12 h of treatment and thereafter at 12-h intervals for the remainder of the 72-h treatment period. After administration of various doses of noradrenaline, adrenaline and serotonin (0.5-2.0 micrograms/kg/h) significant elevation of plasma progesterone was achieved at a dosage of 2.0 micrograms/kg/h (P less than 0.01). The response to adrenaline was greater than that observed for noradrenaline and serotonin (P less than 0.05). Within-treatment comparison to pretreatment samples showed plasma progesterone concentrations to increase within 4 h after the administration of noradrenaline, adrenaline and serotonin (P less than 0.05) and this enhancement was maintained throughout the treatment period (P less than 0.05). The elevation in plasma progesterone concentrations induced by noradrenaline, adrenaline and serotonin was independent of changes in circulating concentrations of luteinizing hormone. These results support a physiological role for endogenous biogenic amines in the control of bovine luteal progesterone production.

Animals↗
PubMed2003

Biogenic peptides and their potential use.

This paper reviews bioactive peptides, biogenic peptides, opioid peptides, immunostimulating peptides, mineral soluble peptides, antihypertensive peptides and antimicrobial peptides originating from food materials and enzymatic hydrolysis of proteins. Antihypertensive peptides are extensively reviewed and have been divided into angiotensin I-converting enzyme inhibitory peptides and others. These peptides are produced in the enzymatic hydrolysate of treated food materials such as milk, animal and fish meat, maize, wheat, soybeans and egg, and also from microbe-fermented products. Peptides with strong antihypertensive effects on spontaneously hypertensive rats are discussed and are divided into high and low angiotensin I-converting enzyme inhibitory activities. In addition, new topics from our studies on antihypertensive peptides are introduced. Efficacies of these peptides in clinical studies and differences with medicinal substances are summarized. Recent studies in this area shown the possibility of using biogenic peptides for improvements in treatment or prevention of hypertension.

Adjuvants, Immunologic↗
PubMed1988

Diabetes-related changes in L-tryptophan-induced release of striatal biogenic amines.

In vivo voltammetry was used to measure the synaptic release of rat striatal dopamine and serotonin after the administration of the amino acid L-tryptophan to streptozocin-induced diabetic rats. Dopamine and serotonin release from rat striatum was studied at a short-term or acute (3-day) interval and a long-term or chronic (3- to 7-wk) interval after the induction of diabetes. The study was also done in age-, sex-, and food-matched controls. The findings show that L-tryptophan decreased dopamine release from rat striatum in nondiabetic rats. The decreased striatal dopamine release, after L-tryptophan administration, was exacerbated in acutely diabetic rats and further exacerbated in chronically diabetic rats. By contrast, rat striatal serotonin release predictably increased after L-tryptophan injection in nondiabetic rats. A further increased striatal serotonin release was seen in acutely diabetic rats. Chronically diabetic rats, however, responded to L-tryptophan with a dramatic and significant decrease in striatal serotonin release. The results show that in acutely diabetic and normal rats, L-tryptophan administration reduced striatal dopamine and increased striatal serotonin release, whereas in chronically diabetic rats, the release of both biogenic amines was decreased. The findings indicate that the progression of diabetes is associated with an impaired ability to release primary neurotransmitter biogenic amines.

Animals↗
PubMed1990

Ultrastructure, morphology and crystal growth of biogenic and synthetic apatites.

The morphology, structure and crystal growth of apatite crystals isolated from calcified turkey tendon and synthetic carbonated apatites have been examined using high resolution transmission electron microscopy. The biogenic apatite consisted of small (35 x 20 x 5 nm) platelike crystals. Despite their irregular shape and ill-defined edges, individual particles were single domain crystals. Lattice images recorded from isolated turkey tendon crystals indicated that the crystallographic c-axis (0001) of apatite lies in the plane of the plate and parallel to the length of the crystallites. Lattice images suggested that the top face corresponds to the (1100) face of carbonated apatite. Lattice fringes observed in platelike crystallites viewed from the side corresponded to the projection of the apatite structure viewed along the [1120] direction. Thus, it can be argued that crystal growth is constrained along the [1100] direction, extends laterally along the [1120] direction, and is maximal along the [0001] direction. This latter direction is aligned with the collagen fiber axis. A mean length to width ratio (1.7) was determined by systemically measuring the maximum distances parallel and perpendicular to the c-axis identified from lattice images of the crystals. Similar information was obtained from lattice images of crystals located in collagen fibres. This confirmed that the morphological and structural features of isolated turkey tendon apatite crystals correlate directly with the in vivo crystallochemical characteristics of apatite. Crystals of synthetic carbonated apatite prepared at 37 degrees C were also platelike and, although generally much larger, had length to width ratios comparable with the turkey tendon apatite. The synthetic carbonated apatites were noticeably more sensitive to radiolytic damage than the turkey tendon crystals. The crystallographic c-axis of the inorganic particles was aligned parallel with the long, physical axis of the plate and the top face was identified as (1100). Similar data were also obtained from noncarbonated synthetic apatite samples. The results of the present study offer critical information about the crystal growth of individual carbonated apatite crystals in calcified turkey tendon and its relationship to the morphology of the crystallites. As similar growth characteristics are expressed in synthetic analogues, the data bring into question the putative regulatory role of the collagen-based matrix upon the nucleation and growth of biogenic apatite.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed2004

The biogenic amine tyramine modulates the adherence of Escherichia coli O157:H7 to intestinal mucosa.

The environmental factors that influence the ability of Escherichia coli O157:H7 to attach to the intestinal mucosa are incompletely understood. In the present study, the ability of one of the most common biogenic amines present in food, tyramine, to influence the ability of E. coli O157:H7 to adhere to murine cecal mucosa was examined. Ex vivo full-thickness sheets of murine cecum were mounted in Ussing chambers, which preserved the enteric nervous system innervation of the luminal epithelia and thereby allowed us to achieve a closer approximation of bacterial adherence than would be encountered in vivo. After exposure of the luminal aspect of the cecum to tyramine, E. coli O157:H7 was added for 90 min. The cecal tissue was then removed and washed, and adhered E. coli O157:H7 was enumerated using a selective medium. Tyramine significantly increased E. coli O157:H7 adherence to cecal mucosa when compared to that of controls. The 50% effective concentration of tyramine was 92.6 microM. Specific adrenergic antagonists were then employed to examine whether the effect of tyramine was mediated through alpha- or beta-adrenergic receptors on the intestinal tissue. Pretreatment of tissues with either the alpha-adrenergic receptor antagonist phentolamine or the beta-adrenergic receptor antagonist propranolol prevented the action of tyramine. Measurement of active transepithelial ion transport and ionic permeability in the cecal sheets before and after the addition of tyramine and E. coli O157:H7 did not show any impairment of tissue viability or transepithelial conductance. Further, tyramine did not influence either the growth of E. coli O157:H7 or the expression of the intimin attachment factor. The present findings suggest that biogenic amines, such as tyramine, present within the food matrix influence host susceptibility to E. coli O157:H7 infection.

Animals↗
PubMed1975

[Biogenic amines and schizophrenia].

Three main biogenic amine hypotheses for the origin of schizophrenia are discussed. The dopamine theory of schizophrenia postulates a pathogenetic connection between the disease and changes in the activity of dopaminergic cells in the brain. The theory is mainly based on findings on the mechanism of action of neuroleptics, on the clinical features and pharmacology of the amphetamine psychosis, and on some amphetamine effects in animals. Several results are in good agreement with the assumption of a state of hyperactivity of central dopamine neurons, whereas others, e.g. the lack of an increased dopamine turnover, are not. According to another theory, schizophrenia is caused by reversible damage to central norepinephrine cells. So far the only empirical basis for this theory is the finding that the activity of dopamine-beta-hydroxylase, a marker enzyme for noradrenaline cells, is lowered in the brains of schizophrenic patients. Thus further confirmation is required. The transmethylation hypotheses assume that hallucinogenic amine metabolites are produced in the body and lead to the appearance of schizophrenic symptoms. Whether or not the occurrence of DMPEA, presumably an oxymethylation product of the dopamine metabolism, is specific for schizophrenics is still open to question; if it is, the meaning of this finding is obscure. Current results leave open the possibility that N-dimethyltryptamine or other N-methylated hallucinogenic biogenic amine metabolites cause the disease; however, this hypothesis is hardly confirmed by positive empirical results.

Amphetamines↗
PubMed2000

Ecological, energetic and economic comparison of anaerobic digestion with different competing technologies to treat biogenic wastes.

In order to get more detailed information for better decision making in future biogenic waste treatment, different processes to treat biogenic wastes in plants with a treating capacity of 10,000 tons of organic household wastes per year were compared. The comparison included life cycle assessments as well as economic considerations for different treating methods. Measurements on compost plants showed that methane emissions are higher than estimated so far. With the tools ECOINDICATOR and UBP anaerobic digestion shows to be advantageous as compared to composting, incineration or combination of digestion and composting, mainly because of a better energy balance. In fully enclosed, professional treatment plants, the specific biotechnological treatment costs are in the range of about 150.-sFr/ton for aerobic, anaerobic and combined technologies. It can be concluded, that anaerobic processes will become considerably more important in the future mainly for ecological reasons.

Bacteria, Anaerobic↗
PubMed1975

[Distribution of biogenic amines in the hippocampal formation in the rabbit].

The hippocampal formation (the hippocampus and the dentate fascia) of the rabbit was studied by histochemical fluorescent method of Falk to determine localization of monoaminergic terminals containing biogenic amines: noradrenalin, dophamine and serotonin. It was shown that monoaminenergic terminals in the hippocampus were in two zones of afferent terminations: in the zone of ending of the perforating way (str. lacunosum-moleculare of fields CA1 and CA2; str. moleculare of the dentate fascia) and in the subgranular zone of the hilum where a part of septofimbrial way terminated on granular neurons of the dentate fascia, the main cellular elements of the hipocampus (pyramidal, granular and basket cells of the hippocampus) did not contain biogenic amines.

Animals↗
PubMed2002

Anti-hypertensive activity of fermented dairy products containing biogenic peptides.

A considerable amount of research has been conducted to study the health benefits of fermented milks. One possible mechanism for the beneficial effects is the involvement of biogenic compounds, which are produced by the action of microorganisms and make the products directly beneficial without the need for live bacteria. Research on the health effects of a pasteurized sour milk, which is fermented by a starter culture containing Lactobacillus helveticus as the predominant microorganism, indicated clear evidence for the involvement of biogenic compounds. In this paper, beneficial effects of sour milk are reviewed with special attention to the effect on anti-hypertension and angiotensin-I converting enzyme inhibitory peptides identified in sour milk.

Animals↗
PubMed2003

Alefacept. Biogen.

Alefacept is a lymphocyte function-associated antigen-3/IgG1 fusion protein that inhibits T-cells by antagonizing CD2, which has been developed and launched by Biogen for the potential treatment of psoriasis. In February 2003, Biogen launched alefacept in the US for use in adults with moderate-to-severe chronic plaque psoriasis, and by March 2003, the company was preparing for psoriasis trials to commence in Japan by the end of December 2003.

Alefacept↗
PubMed2004

[Adaptive value of genes controlling the level of biogenic amines in Drosophila].

The effects of mutations that change the level of biogenic amines (octopamine and dopamine) on stress-reactivity and fitness of Drosophila imagoes are considered. It has been shown that (1) the biogenic amines represent an important but not triggering factor of the development of stress reaction; (2) under normal conditions, reproduction is regulated by genes that control dopamine metabolic pathways (indirectly via regulation of the juvenile hormone level). Under unfavorable conditions, reproduction is regulated by genes that control octopamine metabolism; (3) heat-stress adaptation depends on expression of genes controlling the background level of dopamine.

Adaptation, Physiological↗
PubMed2005

A biogenic volatile organic compounds emission inventory for Yunnan Province.

The first detailed inventory for volatile organic compounds (VOC) emissions from vegetation over Yunnan Province, China was presented. The spatially and temporally resolved inventory was developed based on a geographic information system (GIS), remote sensing (RS) data and field measurement data, such as digitized land-use data, normalized difference vegetation index (NDVI) and temperature data from direct real-time measurement. The inventory has a spatial resolution of 5 km x 5 km and a time resolution of 1 h. Urban, agriculture, and natural land-use distributions in Yunnan Province were combined with biomass factors for each land-use category to produce a spatially resolved biomass inventory. A biogenic emission inventory was developed by combining the biomass inventory with hourly emission rates for tree, shrub and ground cover species of the study area. Correcting for environmental factors, including light intensity and temperature, a value of 1.1 x 10(12) gC for total annual biogenic VOC emissions from Yunnan Province, including 6.1 x 10(11) gC for isoprene, 2.1 x 10(11) gC for monoterpenes, and 2.6 x 10(11) gC for OVOC was obtained. The highest VOC emissions occurred in the northwestern, southwestern and north region of Yunnan Province. Some uncertainties were also discussed in this study.

Algorithms↗
PubMed2005

[Research advances in the effects of elevated atmospheric carbon dioxide and ozone on biogenic VOCs emission].

The increasing concentrations of CO2 and O3 in the troposphere have become a focus of both the domestic and foreign researchers, and the emissions of biogenic volatile organic compounds (BVOCs) can be affected by the change of concentrations. The BVOCs with high chemical reactivity may affect the chemical compositions of lower atmosphere, and promote photochemistry air pollution. At one time, the greenhouse effect and global environment changes will be influenced by the BVOCs. The effects of single and joint action of CO2 and 03 on the emitting characteristics of biogenic volatile organic compounds (BVOCs) were summarized and further researches on this field, especially that of trees in urban areas under the condition of multiple environmental stresses were perspected in this paper.

Acclimatization↗
PubMedDate not supplied

[The effect of a biogenic paste containing hydroxyapatite on the dynamics of the bone integration of immediate implants].

The effect of a biogenic paste containing hydroxylapatite and collagen on the course of bone integration of implants inserted in the hole immediately after tooth or root extraction was studied in dog experiments. Histologic examination has revealed accelerated osteogenesis round the implant in experimental animals vs. the reference ones. This fact permits a conclusion that application of the biogenic paste will be conducive to a more rapid and effective taking in of the implant and, therefore, to a sooner prosthesis.

Animals↗
PubMed1990

[Absorption and release of biogenic amines by the lung during the restorative period after hypovolemic hypotension].

The processes of serotonin and histamine absorption and release by the lungs were studied in dogs during 1 to 3.5 hour hypovolemic hypotension and during 24 hours after blood retains fusion. Absorption of biogenic amines by the lungs tended to increase in all the animals under hypovolemic hypotension. In the group of non-survivors the serotonin absorption by the lungs in the post-terminal period remained increased, while in the group of survivors it came down to normal soon, though the histamine release was increased. The above processes were aggravated in the group of animals whose lungs were affected by oleic acid. It resulted in the absorption of histamine instead of its release. The intensified absorption of biogenic amines by the lungs was accompanied by a quick fall in cardiac output, by the increase in resistance of systemic and pulmonary circulation.

Animals↗