Love- and hate-addiction in delinquent male adolescents.
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Biomedical subjects
Publications and source records attributed to J Molnar.
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Prostaglandin E ( 1 ) (PGE ( 1 ) ), the active ingredient of the drug alprostadil-alpha-cyclodextrin, has been effective in mitigating the clinical manifestations of peripheral arterial occlusive disease (PAOD). PGE ( 1 ) often is administered to patients with the potential for developing serious arrhythmias, presenting potential safety hazards if the drug caused or potentiated arrhythmias. However, PGE ( 1 ) has antiadrenergic properties and, theoretically, might have an antiarrhythmic action. Therefore, the effect of PGE ( 1 ) on frequency and severity of atrial and ventricular arrhythmias was evaluated from 48-hour electrocardiographic recordings in patients receiving PGE ( 1 ) therapy for severe PAOD. No significant effects on arrhythmia frequency or severity, and no evidence of proarrhythmia, was apparent after PGE ( 1 ) administration.
Increased QT dispersion (QT(d)) has been associated with increased risk for ventricular arrhythmias. Pathologic extracellular electrolyte concentrations may result in ventricular arrhythmias. The aim of this study was to evaluate the effect of electrolyte abnormalities on QT(d). Ten consecutive patients with isolated electrolyte abnormalities were selected for each of the following groups: hypokalemia, hyperkalemia, hypercalcemia, hypocalcemia, hypomagnesemia, and normal controls. Standard 12-lead electrocardiography was performed for each patient and average QT, JT, and RR intervals were calculated for each lead. Dispersion of QT, JT (JT(d)), and QTc (QTc(d)) intervals were calculated as the range between the longest and shortest measurements. Compared with controls, only patients with hypokalemia had a greater QT(d) (115 +/- 31 vs. 49 +/- 15 ms), JT(d) (116 +/- 34 vs. 52 +/- 12 ms), and QTc(d) (141 +/- 40 vs. 58 +/- 1 ms), (P < 0.05). In an experimental substudy, seven rats were maintained on K(+) and seven on Mg(2+)-free diet followed by normal diet. Experimental hypokalemia significantly increased QT(d) (10 +/- 4 to 37 +/- 7 ms), and QTc(d) (32 +/- 6 to 79 +/- 27 ms) (P < 0.05), whereas hypomagnesemia did not. Restoration of serum potassium resulted in normalization of dispersion (QT(d), 14 +/- 2; QTc(d), 34 +/- 6 ms). Hypokalemia increases the dispersion of ventricular repolarization that may be responsible for arrhythmias. Even though hyperkalemia, hypocalcemia, and hypercalcemia are known to affect ventricular repolarization, our study shows that they are not associated with increased dispersion.
The authors examined the most frequent causes of hematospermia on their clinical material. They describe--in the order of importance--the examinations needed to discover pathological diagnostics. They call the attention to the importance of differentiation of "clear" hematospermia and hemato-pyospermia and review the possible ways of therapy.
Eleven 4-phenyl-3,5-diacetyl-1,4-dihydropyridines (AcDHPs) [G1-11] substituted at the phenyl ring were synthesized and compared for their cytotoxic activity and multidrug resistance (MDR)-reversing activity in in vitro assay systems. Among them, compound [G7] showed the highest cytotoxic activity against human promyelocytic leukemia HL-60 and human squamous cell carcinoma HSC-2 cells. However, no compounds tested produced radicals at pH 7.4-12.5. The activity of P-glycoprotein (Pgp) responsible for MDR in tumor cells was reduced by compounds [G2, 3, 6, 5, 8, 1, 11], verapamil [VP] and nifedipine [NP]. However, compounds [G4, 7, 10] were hardly active while G9 did not show a MDR reversing effect at 2.0-20.0 micrograms/mL. These data show a relationship between chemical structures and MDR-reversing effect on tumor cells.
Allium victorialis L. (Liliaceae, "Hon-Gyoujya Nin-Niku" in Japanese) was successively extracted with hexane, acetone, methanol and 70% methanol and the extracts were further separated into a total of twenty-five fractions by silica gel and ODS column chromatographies. The biological activities of these four extracts and 25 column fractions were compared. The cytotoxic activity of all extracts and fractions against two oral tumor cell lines was significantly higher than that against normal human gingival fibroblasts, suggesting their tumor-specific action. Three methanol column fractions [M2, M3, M6] and a 70% methanol column fraction [70M6] most effectively reversed the multidrug resistance (MDR) against L5178 mouse T cell lymphoma. The electron spin resonance (ESR) spectroscopy showed that methanol column fractions and 70% methanol extracts produced the highest amount of radical(s) and most efficiently scavenging O2*-, generated by the hypoxanthine-xanthine reaction system, suggesting that the same substances in these fractions display both prooxidant and antioxidant properties. They showed no anti-human immunodeficiency virus (HIV) or anti-Helicobacterpylori activity. These data suggest the medicinal efficacy of Allium victorialis extract.
In order to investigate the correlation between the carcinogenic activity of benz[c]acridines and the electron density, the Huckel orbital method was used. Resonance energies, circuit resonance energies and bond currents of benz[c]acridines were calculated by Aihara's TRE theory. It was shown that these compounds had very stable aromatic characters with positive resonance energies and that the resonance energies per pi-electron values for the compounds with lack of the double bond corresponding to the K-region from the parent skeleton were more stable than those of their parent compounds. 7-Methyl-benz[c]acridine derivatives with the methyl groups at 7-, 7, 9-, 7, 10-, 7, 11-, 7, 9, 10-, or 7, 9, 11-positions except 5, 7-dimethylbenz[c]acridine had potent carcinogenic activity and significantly lower resonance energy per pi-electron.
Tricyclic medical compounds like many other non-antibiotics exhibit antimicrobial activities. Two chemically representative groups were tested in plasmid DNA transformation and replication to assign intracellular target sites responsible for the multiple effects in Escherichia coli and Yersinia enterocolitica cells. To analyse the mechanism of action at the molecular level, the effects of chlorpromazine, 7,8 dioxochlorpromazine, promethazine, methylene blue, imipramine, cannabidiolic acid and tetrahydrocannabidiolic acid were examined at several points in the course of transformation, in plasmid replication and on the topological state of plasmid DNA. Two possible target sites were identified, one of them involving membrane binding sites which participate in plasmid DNA replication. Drug binding at these sites interfered with the replicating plasmid DNA and membrane protein complex, preventing the proper processing of the replication that resulted in plasmid loss. The other in vivo and in vitro effect was observed on the topological state of plasmid DNA. Tricyclic drugs intefered with energy dependent gyrase activity and promoted the relaxation of plasmid DNA, causing disturbances in gene expression and in plasmid replication. The results give insight into the chemical structures connected with significant specific antimicrobial effects.
The abilities of 14 phenothiazines, 8 benzo[a]phenothiazines and 12 benz[c]acridines to induce anti-Escherichia coli activity in mice were compared. Pretreatment with several benzo[a]phenothiazines or benz[c]acridines protected mice from lethal infection of Escherichia coli in a dose-dependent manner, whereas most of the phenothiazines induced much weaker anti-Escherichia coli activity. However, direct contact of Escherichia coli with these compounds or their administration just after bacterial inoculation were ineffective. These data suggest the immunopotentiation activity of benzo[a]phenothiazines and benz[c]acridines.
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In order to study the correlation between the anti-tumor activity of benzo[a]phenothiazines and the electron densities, the Huckel orbital method and modified-neglect-of-diatomic overlap (MNDO) orbital method were used. 9-Methyl-12H-benzo[a]phenothiazine (2), which showed the most potent anticancer activity among benzo[a]phenothiazines, had the highest charge of nitrogen atom (QN), L-region (QL) and M-region (QM) in the molecule. The other derivatives, which showed weaker anticancer activity, had a much reduced value of these charges (QN, QL, QM). The data suggest that stability of pi-electron in 1 benzene ring and 1 naphthalene ring in the benzo[a]phenothiazine skeleton might be responsible for the induction of anticancer activity.
Plasmids of Agrobacterium tumefaciens and Rhizobium meliloti carrying Kanamycin resistance genes were eliminated from 1.4 to 0.2% of the growing bacterial cultures by promethazine and imipramine. As a result of plasmid elimination, the A. tumefaciens plasmidless isolate was not able to induce crown gall tumor on tobacco plants. The plasmidless R. meliloti strain failed to induce nodule formation on alfalfa plants. The efficiency of nodulation was decreased when the bacteria were grown in the presence of the drugs. The antiplasmid effects of the drugs were not prevented by opines, (nopaline and octopine) in Escherichia coli F'lac cells.
The abilities of 14 phenothiazines, 8 benzo[a]phenothiazines and 12 benz[c]acridines to induce an antibacterial effect against Escherichia coli K12 were compared. Several phenothiazines, which showed antiplasmid activity, displayed the most potent antibacterial activity. All benz[c]acridine derivatives were moderately antibacterial, whereas benzo[a]phenothiazines were inactive. The active phenothiazine derivatives had more potent inhibitory activity against fungi, including phytopathogen filamentous, human pathogen filamentous fungi and yeasts, than against gram-positive and -negative bacteria. Taken together with previously reported data, the induction mechanism of antimicrobial and antiplasmid activity by these compounds seems to be different from that of antitumor, differentiation-inducing and carcinogenic activity.
The efficiency of chemotherapy is often decreased by the development of resistance of cancer cells to cytostatic drugs. This phenomenon is in most cases caused by the activity of the various ABC transporters, multidrug-resistance (MDR) gene-encoded p-glycoproteins, that pump anticancer drugs out of the cells. The inhibition of the activities of the MDR proteins MDR1 and MRP was investigated via the administration of two new organosilicon compounds, alis-409 and alis-421. The study was focused on the inhibition of MDR by blocking the ADR1 gene expression and through the inhibition of the pump-function of mdr-p-glycoprotein, in human breast cancer cell lines expressing mrp and prostate cancer cell line (PC-3). Apoptosis induction and the interaction between epirubicin and the silicon-substituted compounds were studied in human MDR-1 gene-transfected mouse lymphoma and its parent cell line, Colo320/MDR-LRP and sensitive subline Colo205, by means of rhodamine 123 accumulation. The activity of MRP1 p-glycoprotein was studied in human breast cancer cell lines such as HTB-26/MRP1 and two MRP-negative breast cancer cell lines, T47D and MCF7, by carboxyfluorescein accumulation, and on a stomach cancer cell line. The activity of MRP in 257P/MDR and its drug-sensitive derivative were studied in human stomach cancer cells by daunorubicin accumulation in a flow cytometer. The two representative organosilicon derivatives, alis-409 and alis-421, showed antiproliferative effects without apoptosis induction. The drug accumulation in the human MDR1 gene-transfected mouse lymphoma cells was increased without down-regulation of the MDR1 gene expression tested by RT-PCR assay. The rhodamine uptake was increased in L5178/MDR1 and Colo320/MDR1-LRP, but not drug-sensitive human breast cancer MCF-7 and T47D, and L5178 mouse lymphoma parent cells in the presence of alis-409 and alis-421. The MRP-mediated carboxyfluorescein accumulation in HTB-26/MRP human breast cancer cells and daunorubicin accumulation in human stomach cancer cells 257P/MDR were not modified by these alis compounds. A synergistic interaction between epirubicin and the silicon-substituted resistance modifiers was found only in MDR1-mediated MDR in the case of colo-320/MDR1-LRP cells and mouse lymphoma cells transfected with the human MDR1 gene. The results indicate that the organosilyl derivatives specifically act on MDR1 p-glycoprotein 170. The alis compounds act on pgp170 in a way which is similar to verapamil isomers.
Various synthetic derivatives of phenothiazines, benzo[a]phenothiazines and benz[c]acridines were compared for their abilities to induce antiplasmid activity against E. coli F'lac plasmid. Several phenothiazine derivatives were much more potent in antiplasmid activity than benzo[a]phenothiazine- or benz[c]acridine derivatives. Their antiplasmid activity seemed to be enhanced by Cl- or CF3- substitution at 2 C atom, and modified by the side chain length and charge at the L-region of the molecules, as well as by hydrophilicity.
Some of the phenothiazines and dibenz[b,f]azepines exert an antiproliferative effect on HEp-2 and rat prolactinoma cells. The same compounds also have effects on different membrane-bound biochemical events, such as H2O2 formation and the peroxide-generated chemiluminescence of polymorphonuclear leukocytes. The superoxide dismutase inhibition by 7,8-dioxochlorpromazine and 6,9-dioxochlorpromazine have some relation to the growth inhibitory action on the growth of HEP-2 and prolactinoma cells in vitro. The antiproliferative effects of phenothiazines were synergized with resistance modifiers like verapamil, omeprazole and tubulozole-C, due to increased drug-influx or decreased drug-efflux and due to possible action on the cytoskeleton.