Antioxidant action of a new flavonic derivative in acute carbon tetrachloride intoxication

The antioxidant potential of a new flavonic derivative named conventionally theophylline-rutoside [TR-1722] was estimated by the measurement of G-6-Pase activity (marker enzyme for the endoplasmic reticulum), catalase activity (enzyme involved in the antioxidant defence process), and total -SH groups from the hepatic homogenate, using CCl4 as a free radical generating model. To show changes in the permeability of the hepatocyte membrane, the activity of lactate dehydrogenase (LDH) in plasma was determined. The obtained results suggest that TR-1722 acts by curtailing both lipid peroxidation and alkylation processes.

MP-3022, a new putative antagonist at pre- and postsynaptic 5-HT1A receptors

The receptor binding and pharmacological profile of the new, putative 5-HT1A receptor antagonist MP-3022 (4-[3-(benzotriazol-1-yl)propyl]-1-(2-methoxyphenyl)piperazine) were studied. Another 5-HT1A receptor antagonist, (S)-WAY 100135 ((S)-N-tert-butyl-3-[4-(2-methoxyphenyl)piperazine-1-yl]-2- phenylpropanamide), was used as a reference drug in functional models. MP-3022 showed a high affinity (Ki) of 25 nM and 69 nM, respectively, at 5-HT1A binding sites and alpha 1-adrenoceptors in vitro. The Ki values of MP-3022 in relation to other binding sites examined (5-HT2A, alpha 2- or beta-adrenoceptors, dopamine D1 and D2) were 20-100-fold lower. In functional studies, MP-3022 significantly attenuated the 8-OH-DPAT (8-hydroxy-2-(di-n-propylamino)tetralin)-induced decrease in the population spike evoked in the CA1 cell layer of the hippocampal slice preparation, without producing its own effects. The 8-OH-DPAT-evoked increase in the corticosterone concentration in the serum as well as the 8-OH-DPAT-mediated decrease in the 5-HT turnover in the hippocampus were attenuated by MP-3022. MP-3022 increased the serum corticosterone concentration only at the highest dose used, but it did not change the 5-HT turnover in the hippocampus. Like MP-3022, (S)-WAY 100135 antagonized the 8-OH-DPAT-induced effects. It has also been demonstrated that (S)-WAY 100135 is devoid of an intrinsic activity at 5-HT1A receptors. The data obtained demonstrate that, like (S)-WAY 100135, MP-3022 behaves like a functional antagonist at pre- and postsynaptic 5-HT1A receptors.

[The use of prostaglandin compounds in treating glaucoma]

The theoretical part of this paper presents the mechanism of the IOP lowering effect using these drugs, the indications of treatment and the main side effects. The second part consist of the experimental study made on rabbits, using the izopropilic ester of (+)Cloprostenol as an hypotensive agent. We have registered the IOP values and the main side effect--conjunctival hyperemia. The third part consist of the clinical study, made on a test lot of 23 patients. We have used the same substance and in the experimental study, as a unique treatment or in association with a beta-blocker or a pilocarpine derivative. The following-up has implied: the IOP, the ophthalmoscopic appearance of the optic disc, the visual field, the visual acuity and the main side effects. In the end, we have formulated the conclusions of these studies.

[The differential diagnosis between symptomatic and idiopathic retinal detachments]

The paper presents a synthesis of today's means for differential diagnosis between symptomatic and idiopathic retinal detachment, considering that the retinal detachment remains an ocular emergency, with high invalidity potential. The characteristic difficulties of this diagnosis are also detailed. The different medical attendance of the two types of retinal detachment requires a rigorous differential diagnosis, according the leading part to the ophthalmological examination. There are also illustrated up-to-date diagnosis tests, less invasive and more informative, such as: CT and MRI. The survey highlights the value still relative of the majority of these investigations and the fundamental significance of the histological examination.

[The explantation and replacement of artificial lens implants]

The paper presents the statistical study of the appearance of explantation on the whole of artificial lenses implants, at the Ophthalmology Service of the Central Military Hospital during the years 1989-1993. The statistics relies on the review of data extracted from the operation registers, elaborated during the mentioned period, followed by their computerized processing and plotting. The authors also referred to the types of postoperative complications and their weight in the genesis of the explanation, as well as their distribution related to the sort of implanted intraocular lens. The survey also illustrates the long-run evolution of the reimplantation percentage. The results are comparatively reviewed to those in the specialty literature.

[Pneumatic retinopexy with SF6]

Pneumatic retinopexy has been recently reported as an alternative procedure in the treatment of retinal detachments. This technique may be considered if the break is no larger than the 1 o'clock hour, the break is located superiorly between 8 o'clock and 4 o'clock and there is no proliferative vitreoretinopathy greater than C1. The expandable gas SF6 (sulphur hexafluoride) has been used in the treatment of 16 cases of retinal detachment. Two of them were new cases treated with pneumatic retinopexy and cryotherapy applications and they were both successful. The other 14 cases were redetachments, so the treatment was completed by scleral buckling in 9 cases and scleral buckling with permanent implants of silicon in 5 cases. The rate of success was 3 to 9 and 2 to 5. For the rest of 9 cases vitrectomy or silicon oil injection would have been useful. Pneumatic retinopexy proved to be a low-price surgical treatment easy to use even in a consulting room, in one or two-session method. It may be performed as a single procedure for new cases of superior retinal detachments or in addition to other surgical techniques on selected cases.

[Replacement of an intervertebral disc, using a ceramic prosthesis, in the treatment of degenerative diseases of the spine.]

The authors tested in experimentally a suitable shape and approach to replacement of an intervertebral disc by means of an endoprosthesis made from glass-ceramic material of Lasak Co. In experiments on post-mortem material they succeded eventually in creating the optimal shape and finding a route of administration of the endoprosthesis into the intervertebral space. The endoprosthesis should create a spondylodesis and primary fixation of the affected portion of the lumbar spine. In some instances it thus will not be necessary, after insertion of the ceramic prosthesis into the intervertebral space, to make a supplementary instrumental fixation. Key words: ceramic endoprosthesis, replacement of degenerated lumbar intervertebral disc.

[Corneal transplantation today]

Corneal transplant become a surgical procedure which is performed with success in more many ophthalmological medico-surgical centers. This way it raised a fully experience concerning selection of cases and the preservation of the graft, surgical technique and the graft rejection. The authors present a general view of the problems concerning keratoplasty making a briefly summary of the indications, contraindications and prognosis of this technique, screening of donor tissue and a little larger one the surgical technique with his problems: trephining, preserving the donor tissue and placing the graft, and also the postoperative problems--suture removal, visual correction and corneal transplant rejection.

Structure-activity relationship studies of central nervous system agents. 13. 4-[3-(Benzotriazol-1-yl)propyl]-1-(2-methoxyphenyl)piperazine, a new putative 5-HT1A receptor antagonist, and its analogs

A new set of 4-alkyl-1-(o-methoxyphenyl)piperazines containing a terminal benzotriazole fragment were synthesized, and their 5-HT1A and 5-HT2 affinity was determined. It was shown that the benzotriazole moiety contributes to both the 5-HT1A and 5-HT2 receptor affinity. It was demonstrated in several behavioral models that 4-[3-(benzotriazol-1- yl)propyl]-1-(2-methoxyphenyl)piperazine (11) is a new, potent presynaptic and postsynaptic 5-HT1A receptor antagonist. However, it is not selective for 5-HT1A versus alpha 1 receptors.

The role of 5-hydroxytryptamine1A (5-HT1A) receptors in the anticonflict activity of beta-adrenoceptor antagonists

Using the conflict drinking test as a model, we studied in rats the effect of the nonselective beta-adrenoceptor blockers pindolol and cyanopindolol which bind to 5-HT1A and 5-HT1B receptors, and of the selective beta 1- and beta 2-adrenoceptor antagonists betaxolol and ICI 118,551, respectively, which have a negligible affinity for 5-HT receptors. Both pindolol (2.0-8.0 mg/kg) and cyanopindolol (0.5-2.0 mg/kg) showed an anticonflict effect, having dose dependently increased the number of punished licks. On the other hand, neither betaxolol nor ICI 118,551--administered separately or in combination--affected the punished responding. The anticonflict effects of pindolol and cyanopindolol were completely abolished by the 5-HT1A receptor and alpha 1-adrenoceptor antagonist 1-(2-methoxyphenyl)-4-[4-(2-phtalimmido)butyl]piperazine (NAN-190), but were not modified by the selective alpha 1(-)-adrenoceptor antagonist prazosin. The effects of pindolol and cyanopindolol were also not modified in animals with lesions of 5-HT neurons, produced by p-chloroamphetamine (PCA). Moreover, it was also found that the anticonflict effects of pindolol and cyanopindolol in PCA-pretreated rats were antagonized by NAN-190 but not prazosin. Our results indicate that the anticonflict effects of pindolol and cyanopindolol depend on their agonist action on postsynaptic 5-HT1A receptors.

Antagonism of (+)WAY 100135 to behavioral, hypothermic and corticosterone effects induced by 8-OH-DPAT

The 5-HT1A antagonistic properties of (+)-N-tert-butyl-3-[4-(2-methoxyphenyl)piperazin-1-yl]-2-phenyl pro panamide ((+)WAY 100135) were studied. Its effect on the 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT)-induced behavioral syndrome (flat body posture and reciprocal forepaw treading) in reserpine-pretreated rats, the stimulus effect in a drug discrimination model in rats, the lower lip retraction in rats, the hypothermia in mice and secretion of corticosterone in rats, i.e. responses mediated by 5-HT1A receptors, were examined. (+)WAY 100135 administered in doses up to 10 mg/kg dose-dependently antagonized all the above responses to 8-OH-DPAT, the lowest effective doses ranging from 1.25 to 2.5 mg/kg. At the same time, (+)WAY 100135 alone given in doses of 1.25-10 mg/kg did not mimic the activity of 8-OH-DPAT in the tests used. Our results indicate that (+)WAY 100135 is an antagonist of pre- and postsynaptic 5-HT1A receptors devoid of agonist properties.

[The therapeutic prospects in glaucoma treatment]

The appearance of new drugs in glaucoma's treatment has the aim to reduce the ocular hypertonia and to preserve the visual field maintaining the integrity of visual fibres which form the optic nerve. The authors review the drugs which have action on the trabeculum, such as parasympathomimetics, adrenalin, glicocorticoid antihormones and colchicine, also influencing the ciliary processes as inhibitors of carbonic anhydrase, and the drugs which have an action on the uveoscleral paths such as prostaglandines.

[The artificial lens implant]

The paper presents a short history of the cataract intervention, starting from the lens luxation in vitreum and going to the implant of artificial lens. From the three classes of artificial lenses, up-to-date options are the posterior chamber artificial lenses. Today, in 80% of the cases, artificial lens implant is done, 80% of the implanted lenses being posterior chamber lenses. The paper also exposes various operatorial techniques, post-operatorial evolution and the results obtained.

Discriminative stimulus properties of (+)-oxaprotiline in rats

Using a drug discrimination procedure on a fixed ratio (FR) 10 schedule of reinforcement, rats were trained to distinguish between the stimulus properties of the selective inhibitor of noradrenaline uptake (+)-oxaprotiline ((+)-OXA) and saline. Fifty per cent of the rats that learned to reliably discriminate (+)-OXA from saline, reached high discrimination accuracy. In substitution testing, maprotiline (MAP) and desipramine (DMI) produced dose-related responding on the (+)-OXA lever. (-)-OXA failed to show substitution. The results of our findings demonstrate that (+)-OXA may be used as a discriminative cue in rats. The NA uptake inhibition seems to be involved in the effect of this drug.

[The effect of the ascorbic acid-Cu (II) couple on enzyme activity]

Ascorbic acid (AA), Cu (II) and their association affect in different ways the activity of G6P-ase and G6PDH from the rat hepatic cytoplasm enriched in microsomes. G6P-ase is inhibited at a wide range of concentrations: 200-2 mM AA and 1-0.1 mM Cu (II). The association AA-Cu in the above mentioned concentrations, proved to be a stronger inhibitor than AA or Cu (II) introduced separately in the incubation medium. The activity of G6PDH is stimulated by AA-Cu (II) association and inhibited by AA in the dialyzed and nondialyzed cytoplasm. Cu (II) inhibits the activity of G6PDH in the nondialyzed cytoplasm and stimulates it following dialysis. The compounds with recognized antiradical action prove to be inefficient in restoring the activity of G6PDH affected by the AA-Cu (II) association.

The anxiolytic-like effects of 5-hydroxytryptamine3 (5-HT3) receptor antagonists

The effect of six 5-HT3 receptor antagonists: ondansetron (0.01-3 mg/kg ip), granisetron (0.01-1 mg/kg ip), zacopride (0.01-3 mg/kg ip), tropisetron (0.001-0.1 mg/kg ip), MDL 72222 (0.01-3 mg/kg ip) and DAU 6215 (0.01-3 mg/kg sc) were examined in the conflict drinking test (Vogel test) and in the elevated plus-maze test in rats. Ondansetron (0.1-0.3 or 1 mg/kg), zacopride (0.1-1 mg/kg) and tropisetron (0.01 mg/kg) increased the punished responding in the Vogel test and showed anxiolytic effects in the elevated plus-maze test. Their effects were limited to a narrow dose range and were not dose-dependent. Granisetron (0.1 mg/kg) exhibited an anti-conflict activity, but was ineffective in the elevated plus-maze test. MDL 72222 and DAU 6215 were ineffective in both those tests. On the other hand, diazepam (2.5-10 mg/kg), used as a reference drug, was active in either procedure and its effects were dose-dependent. These results indicate that an anxiolytic-like activity is not a common characteristic of 5-HT3 receptor antagonists. Moreover, even the anxiolytic action of drugs which were active in the experimental models used should be accepted with caution.

The action of the couple ascorbic acid--Cu(II) on NAD(+)-coenzymatic function

The coenzymatic capacity of NAD+ decreases by exposing it to the action of ascorbic acid--Cu(II) system, a generator of free radicals. The participation of the radicals in degrading NAD+ depends on the nature of the buffer, incubation medium pH, temperature, incubation time. Thiourea, IK, GSH, cysteine, mannitol, albumine reduce to different extents the noxious action of the radicals. The decrease of the coenzymatic function of NAD+ is caused by the break of esther and anhydride links, evidenced by releasing th cian-sensitive compounds--nicotinamide riboside and nicotinamide ribonucleotide. Also the presence of ortophosphate was demonstrated.

[Sympathetic ophthalmia with an atypical onset]

Authors report the case of a patient in whom a sympathetic ophthalmia with posterior onset under the aspect of a massive CRSC was diagnosed. The clinical and therapeutic aspects are described in detail.

Malondialdehyde and 4-hydroxynonenal protein adducts in plasma and liver of rats with iron overload

In hepatic iron overload, iron-catalyzed lipid peroxidation has been implicated in the mechanisms of hepatocellular injury. Lipid peroxidation may produce reactive aldehydes such as malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), which may form aldehyde-protein adducts. We investigated whether lipid peroxidation occurred in rats fed a diet containing 3% carbonyl iron for 5-13 wk, and if this resulted in the formation of MDA- and 4-HNE- protein adducts. Chronic iron feeding resulted in hepatic iron overload (greater than 10-fold) and concomitantly induced a 2-fold increase in hepatic lipid peroxidation. Using an antiserum specific for MDA-lysine protein adducts, we demonstrated by immunohistochemistry the presence of aldehyde-protein adducts in the cytosol of periportal hepatocytes, which co-localized with iron. In addition, MDA- and 4-HNE-lysine adducts were found in plasma proteins of animals with iron overload. Only MDA adducts were detected in albumin, while other plasma proteins including a approximately 120-kD protein had both MDA and 4-HNE adducts. In this animal model of hepatic iron overload, injury occurs primarily in periportal hepatocytes, where MDA-lysine protein adducts and excess iron co-localized.

[Present problems in health services and health care]

In order to deal with and resolve contemporary problems of the health services and health care it is important to outline their concept, contents and definition as well as those of their fundamental constituents--the material, technical basis, workers and their activities, which determine the state health policy. The author analyzes from this aspect the hitherto accomplished development with regard to all basic constituents and discusses the problem of the relationship of the intensity and extensity of activities of the health services and health care. A foremost part is played by medical is played by medical science--medicine, its state, knowledge assembled by students during their undergraduate studies and medical graduates during their postgraduate training. A substantial and decisive component of the health services as regards therapeutic and preventive care is formed by health workers and the quality of their work which depends on objective as well as subjective factors which are analyzed. Health services do not comprise only practical activities but social medicine and the organization of health services are very important scientific disciplines which participate in the quality of activities. This scientific discipline was founded by prominent personalities. It must be stated that in practical medical work leading authorities do not always respect the scientific character of the discipline and thus very complicated problems arise as regards scientific control. All these problems from the aspect of the department of social medicine and organization of health services as well as subjective and scientific control must be resolved from the aspect of reconstruction of society.

[The reasons for failure in retinal detachment]

Detachment of the retina is still a very serious ocular disease which poses many problems to the ophthalmologist. The study shows the causes of the treatment failure in this disease on the basis of the authors' experience and the specially literature.