Biological studies on the effects of some therapeutic procedures used in psychiatry.

The glucose, lactate, and pyruvate levels, the lactate/pyruvate ratio and pH were studied in serum and CSF of patients with schizophrenia, reactive psychosis, symptomatic or circular psychosis under the effect of atropine coma, ES and pentetrazole convulsions, tranquilizer treatment and combined therapy. Convulsive therapy caused a disorder in cerebral carbohydrate metabolism while no similar changes were induced by atropine coma. Anaerobic carbohydrate metabolism was stimulated by combined therapy. This treatment had the best effect and the changes caused by it were slighter than in the case of convulsive therapy. The changes in EEG frequency corresponded to the biochemical changes.     

Biological evaluation of some selected cyclic imides: mitochondrial effects and in vitro cytotoxicity

Cyclic imides such as succinimides, maleimides, glutarimides, phthalimides and their derivatives contain an imide ring and a general structure -CO-N(R)-CO- that confers hydrophobicity and neutral characteristic. A diversity of biological activities and pharmaceutical uses have been attributed to them, such as antibacterial, antifungal, antinociceptive, anticonvulsant, antitumor. In spite of these activities, much of their action mechanisms at molecular and cellular levels remain to be elucidated. We now show the effects of several related cyclic imides: maleimides (S2, S2.1, S2.2, S3), glutarimides (S4, S5, S6), 4-aminoantipyrine derivatives (L1, F1, AL1, F1.14, F1.2) and sulfonated succinimides (RO1, FA, FE, FD, MC, DMC) on isolated rat liver mitochondria, B16-F10 melanoma cell line, peritoneal macrophages and different bacterial streams. The effects on mitochondrial respiratory parameters, cell viability and antibacterial activity were also evaluated. The results indicated that S3, S5 and S6 caused an increased oxygen consumption in the presence of ADP (state III) or its absence (state IV), while all other compounds decreased those parameters at different degrees of inhibition. All the compounds decreased the respiratory control coefficient (RCC). Loss of cell viability of peritoneal macrophages and the B16-F10 cell line was observed, L1 and S2.1 being more effective. S1, S2, S3, L1 and F1 compounds showed antibacterial activity at experimental concentrations.     

Biological activity of some conjugated gibberellins

Summary The biological activity of several gibberellin (GA) conjugates was studied and compared with that of the corresponding free GAs. The following conjugates were included: O(3)--d-glucopyranosides of GA₁, GA₃ and GA₄; O(13)--d-glucopyranosides of GA₁, GA₃ and GA₅; O(13)--d-glucopyranosyl-GA₅--d-glucopyranosyl ester; GA₃--d-glucopyranosyl ester and GA₃--d-glucopyranosyl ester; N-GA₃-oyl-glycine, its methyl ester, N-GA₃-oyl-glycylglycine, and N-GA₃-oyl-proline. All compounds were synthesized chemically but some of them are known to occur as endogenous plant products, or to be formed in plants upon application of a free GA. Activity was determined in the dwarf pea, dwarf corn, dwarf rice, and lettuce hypocotyl bioassays. The GA conjugates were found to posses different relative activities depending on the chemical structure, the bioassay system, and the site of application (shoot or roots). It is concluded that the activity of GA conjugates as measured in different bioassays is based upon the ability of plant enzymes and possibly of certain microorganisms to hydrolyze glucosidic, glucosyl ester, and amide-like linkages.Gibberellins-XLVIII. Part XLVII=Adam et al. (1976b)     

Biological effects of resveratrol

Resveratrol (3, 4', 5 trihydroxystilbene) is a naturally occuring phytoalexin produced by some spermatophytes, such as grapevines, in response to injury. Given that it is present in grape berry skins but not in flesh, white wine contains very small amounts of resveratrol, compared to red wine. The concentrations in the form of trans- and cis- isomers of aglycone and glucosides are subjected to numerous variables. In red wine, the concentrations of the trans-isomer, which is the major form, generally ranges between 0.1 and 15 mg/L. As phenolic compound, resveratrol contributes to the antioxidant potential of red wine and thereby may play a role in the prevention of human cardiovascular diseases. Resveratrol has been shown to modulate the metabolism of lipids, and to inhibit the oxidation of low-density lipoproteins and the aggregation of platelets. Moreover, as phytoestrogen, resveratrol may provide cardiovascular protection. This compound also possesses anti-inflammatory and anticancer properties. However, the bioavailability and metabolic pathways must be known before drawing any conclusions on the benefits of dietary resveratrol to health.     

Biological effects of ultrasound

When ultrasound is absorbed by tissue, heat is produced which may be destructive or, if controlled, can be therapeutic. In addition, ultrasound produces biological effects which cannot be explained on the basis of heating alone. Under certain exposure conditions production of ultrasonic lesions in brain tissue can be explained on a purely thermal basis. Examples of nonthermal effects of ultrasound include changes in growth, mitotic index and the production of chromosomal aberrations in plant roots.     

Biological properties of some nitrogen-fixing associative enterobacteria

Enterobacteria isolates from potato tubers were able to fix nitrogen, to protect plants against phytopathogens and to produce phytohormones thus increasing the plant yield. These isolates were previously phenotypically identified as Erwinia carotovora; however, they differed from typical E. carotovora in a number of biological characteristics and were found to be nonphytopathogenic (avirulent) due to the lack of pectate lyase activity. A data matrix, containing 31 strains and 105 biological characteristics was used for computer cluster analysis. The avirulent strains formed a separate cluster more closely related to Klebsiella spp. strains (with a 0.67 level of similarity) than to typical phytopathogenic bacteria of the E. carotovora group (with a 0.48 level of similarity). A phylogenetic analysis based on restriction polymorphisms of an amplified ribosomal DNA spacer region revealed that the avirulent strains studied here were different from all Erwinia, Klebsiella and other enterobacteria species strains. The AP PCR/hybridization technique showed cross homology of amplified DNA of these avirulent strains and a lack of such homology with the DNA from strains of other species. Numerical taxonomy data, rDNA analysis and AP PCR/hybridization assays confirmed that these avirulent bacteria may be regarded as an independent group of enterobacteria.     

Antifungal effects of the 3-methyl-5-aminoisoxazole-4-thiocyanate on some dermatophytes

This preliminary research demonstrates the dose dependent antimycotic effect of 3-methyl-5-aminoisoxazole-4-thiocyanate against a number of animal and human dermatophytes. The in vitro results suggest potential medical applications.     

Biological effects of magnetic fields

The literature about the biological effects of magnetic fields is reviewed. We begin by discussing the weak and/or time variable fields, responsible for subtle changes in the circadian rhythms of superior animals, which are believed to be induced by same sort of "resonant mechanism". The safety issues related with the strong magnetic fields and gradients generated by clinical NMR magnets are then considered. The last portion summarizes the debate about the biological effects of strong and uniform magnetic fields.     

Biological effects of electromagnetic fields

Life on earth has evolved in a sea of natural electromagnetic (EM) fields. Over the past century, this natural environment has sharply changed with introduction of a vast and growing spectrum of man-made EM fields. From models based on equilibrium thermodynamics and thermal effects, these fields were initially considered too weak to interact with biomolecular systems, and thus incapable of influencing physiological functions. Laboratory studies have tested a spectrum of EM fields for bioeffects at cell and molecular levels, focusing on exposures at athermal levels. A clear emergent conclusion is that many observed interactions are not based on tissue heating. Modulation of cell surface chemical events by weak EM fields indicates a major amplification of initial weak triggers associated with binding of hormones, antibodies, and neurotransmitters to their specific binding sites. Calcium ions play a key role in this amplification. These studies support new concepts of communication between cells across the barriers of cell membranes; and point with increasing certainty to an essential physical organization in living matter, at a far finer level than the structural and functional image defined in the chemistry of molecules. New collaborations between physical and biological scientists define common goals, seeking solutions to the physical nature of matter through a strong focus on biological matter. The evidence indicates mediation by highly nonlinear, nonequilibrium processes at critical steps in signal coupling across cell membranes. There is increasing evidence that these events relate to quantum states and resonant responses in biomolecular systems, and not to equilibrium thermodynamics associated with thermal energy exchanges and tissue heating.     

Biological effects of noble gases

Noble gases are known for their inertness. They do not react chemically with any element at normal temperature and pressure. Through that, some of them are known to be biologically active by their sedative, hypnotic and analgesic properties. Common inhalation anesthetics are characterized by some disadvantages (toxicity, decreased cardiac output, etc). Inhalation of xenon introduces anesthesia and has none of the above disadvantages, hence xenon seems to be the anesthetic gas of the future (with just one disadvantage - its cost). It is known that argon has similar anesthetic properties (under hyperbaric conditions), which is much cheaper and easily accessible. The question is if this could be used in clinical practice, in anesthesia of patients who undergo treatment in the hyperbaric chamber. Xenon was found to be organ-protective. Recent animal experiments indicated that xenon decreases infarction size after ischemic attack on brain or heart. The goal of our study is to check if hyperbaric argon has properties similar to those of xenon.