Inhibition of evoked glutamate release by the neuroprotective 5-HT(1A) receptor agonist BAY x 3702 in vitro and in vivo

Brain ischemia provoked by stroke or traumatic brain injury induces a massive increase in neurotransmitter release, in particular of the excitotoxin glutamate. Glutamate triggers a cascade of events finally leading to widespread neuronal cell damage and death. The aminomethylchroman derivative BAY x 3702 is a novel neuroprotectant which shows pronounced beneficial effects in various animal models of ischemic brain injury. As shown previously BAY x 3702 binds to 5-HT(1A) receptors of different species in subnanomolar range and is characterized as a full receptor agonist. In this study we investigated the influence of BAY x 3702 on potassium-evoked glutamate release in vitro and ischemia-induced glutamate release in vivo. In rat hippocampal slices BAY x 3702 inhibited evoked glutamate release in a dose-dependent manner (IC(50)=1 microM). This effect was blocked by the selective 5-HT(1A) receptor antagonist WAY 100635, indicating that BAY x 3702 specifically acts via 5-HT(1A) receptors. In vivo, release of endogenous aspartate and glutamate was measured in the cortex of rats by microdialysis before and after onset of permanent middle cerebral artery occlusion. Single dose administration of BAY x 3702 (1 microg/kg or 10 microg/kg i.v.) immediately after occlusion reduced the increase and total release of extracellular glutamate by about 50% compared to non-treated animals, whereas the extracellular aspartate levels were not significantly affected. Inhibition of glutamate release may therefore contribute to the pronounced neuroprotective efficacy of BAY x 3702 in various animal models of ischemic brain damage.

[Follow-up study of children after functional endoscopic sinus surgery]

In the pathology of recidive infection of upper and lower respiratory tract the chronic diseases of the paranasal sinuses play an important role. The authors ordered for their FESS patients a control examination, 1 year after operation. They present examination data of 30 patients. They analyzed the respiratory complaints, the results of anterior rhinoscopy and CT, the allergies and the performed surgery. 17 patients were healed, 10 got better and in 3 cases the complaints were unchanged. Allergic rhinitis or bronchial asthma were found in more then 2/3 of their patients. According to their opinion the FESS is effective method in treatment of he chronic respiratory tract infections. In the background of the recidive respiratory tract inflammation the chronic diseases of the paranasal sinuses are often found if they are looked for.

A new method for reconstruction of the larynx after vertical partial resections

The indications and problems of organ-preserving vertical partial laryngectomy (VPL) in cases of T1b glottic or T2 glottic and subglottic cancers are well known. The first and imperative requirement for the surgeon is adequate resection of tumor while the second prerequisite is the safe and successful correction of the excised portion of the anterolateral wall of the larynx. Since reconstruction of the defect can cause significant challenges for surgeons, the main requirements are an adequate lumen for breathing, a smooth surface for epithelialization, voice restoration and good deglution. Krajina's method for reconstruction of the larynx utilizes pedicled sternohyoid fascia, which is thin, elastic, well adaptable to defects, and resistent to infection or saliva. By providing a large surface for covering defects, granulations and synechiae can be prevented. We now use the superficial fascia colli as a new method for reconstruction of laryngeal defects after frontolateral partial resections. The technique was first refined experimentally in dogs. A Leroux-Robert partial laryngectomy was carried aut on five animals and laterally pedicled fascia was sutured to the edge of the defect created. At 2-week intervals through 8 weeks after the operation fixation, vascularization and epithelialization were examined histologically. To date, clinical reconstruction with the fascial flap has been used in 29 cases. Because the flap has a very low metabolism, no necrosis was seen. Functional results of respiration, phonation and swallowing have been good. These findings show that laterally pedicled fascia with the bipedicled sternohyoid muscles can play an important role in laryngeal reconstruction.

[The relationship between benign breast proliferation (fibrocystic mastopathy) and the appearance of breast carcinoma]

Fibrocystic mastopathy (FM), a benign lesion, is considered by many author like a premalignant lesion. Breast carcinoma (CA) represents the most frequent female tumor and the second mortality cause through cancer, after the bronchopulmonary cancer. At the Department of Pathology from Tg. Mureş, we selected 190 cases, for 10 month: 102 presented FM, 41 CA and 47 CA + FM. In every case, we have examined 2 slides stained with HE. In difficult cases, we performed special stains (van Gieson, H-PAS, Alcian). We studied the pulmonary tumor, adjacent mammary tissue and axillary lymph nodes. The present data of literature and the experience of the Department of Pathology from Tg. Mureş showed a strong relationship between the presence of FM and the appearance of CA: both lesions have a common field of hormonal disfunction and intraductal and intralobular hyperplasia (an microscopic feature of mastopathy) increase the risk of CA.

Investigation of mandelic acid bonding on Pirkle type chromatographic stationary phases by Raman spectroscopy

The bonding of mandelic acid enantiomers has been studied on benzene-leucine, dinitrobenzene-leucine and dinitrobenzene-phenylalanine type chiral stationary phases connected to zeolite A supports. The pi-donor, pi-acceptor and H-bonding interactions responsible for diastereomer pair formations can be studied under quasi in situ chromatographic conditions by Fourier transform Raman and surface enhanced Raman spectroscopic techniques. Structural differences between diastereomer pairs result in observable spectral differences at a phase load of approx. 50%. It was shown that the decreasing pi-acceptor character of the phase is associated with its increasing capability of H-bond formation. Correlating spectral data to chromatographic results it can be concluded that, in addition to H-bonding as well as to pi-donor-pi-acceptor interactions, steric hindrances due to bulky moieties of either the stationary phase or the analyte molecules are of importance in successful separations.

[Genetic counseling and prenatal care after medications during the first trimester]

Analysis of the outcome of 127 pregnancies with first trimester medication (8.4% of the total number of the patients seeking genetic advice in 1997 at the Institute of Medical Genetics in Szeged) was carried out. The gestational age at the time of the medication and genetic counselling, the indications of the treatment, the drugs, the estimated fetal risk, and results of genetic ultrasound examinations and pregnancy outcome were evaluated. The majority of pregnant woman (78%) asked for genetic counselling before the 12. gestational week. The main indications the treatment were: infections, psychiatric-neurologic (depression, anxiety, epilepsy), endocrine (diabetes, hyperthyreoidism), and cardiovascular diseases and gastrointestinal problems. The main groups of the drugs were: antibiotics, antipyretic-, antidepressive-, antidiabetic- and antihypertensive drugs. When the multiple medication was conducted by simultaneous administration of two or more drugs, a complex risk calculation was performed. The fetal risk was higher than 10% in 31 cases (24%). The ultrasound examinations performed by qualified sonographer contributed to a correct evaluation and to reliable follow-up of pregnancies. No suspicious ultrasound finding was reported in the first trimester. However, a severe fatal brain malformation was found in a second trimester pregnancy, which was terminated by the couple's request in the 18th gestational week. A complete follow-up was obtained in 70.9% (90) of the cases. Out of 64 pregnancies intended to continue to term 4 fetal malformations were found. Of them three malformations (patent ductus arteriosus, Robin sequence and a ventricular septal defect) were explored at birth or in the newborn period. The actual 6.3% of fetal malformations was higher compared to the rate expected at birth, but almost equal to the rate of congenital malformation found up to the end of the first year of age in Hungary.

Induction of protective immunity in chickens immunised with plasmid DNA encoding infectious bursal disease virus antigens

Direct DNA inoculations were used to determine the efficacy of gene immunisation of chickens to elicit protective immune responses against infectious bursal disease virus (IBDV). The vp2 gene of IBDV strains GP40 and D78, and the vp2-vp4-vp3 encoding segment of strain D78 were cloned in an expression vector which consisted of human cytomegalovirus (HCMV) immediate early enhancer and promoter, adenovirus tripartite leader sequences and SV40 polyadenylation signal. For purification of vaccine-quality plasmid DNA from E. coli, an effective method was developed. Chickens were vaccinated by inoculation of DNA by two routes (intramuscular and intraperitoneal). Two weeks later, chickens were boosted with DNA, and at 2 weeks post-boost, they were challenged with virulent IBDV strain. Low to undetectable levels of IBDV-specific antibodies and no protection were observed with DNA encoding VP2. However, plasmids encoding VP2-VP4-VP3 induced IBDV-specific antibodies and protection in the chickens. DNA immunisation opens a new approach to the development of gene vaccines for chickens against infectious diseases.

Potency test of inactivated Newcastle disease vaccines by monoclonal antibody blocking ELISA

The potency of 27 different inactivated Newcastle disease (ND) vaccines was determined by immunization and challenge tests. Three- and four-week-old SPF chickens were immunized with 1/50 dose of vaccines. The chickens were bled and challenged three weeks later. The protected/challenged ratio was determined. Serum samples were tested by the haemagglutination inhibition (HI) test and by a monoclonal antibody (MAB) blocking enzyme-linked immunosorbent assay (B-ELISA). Ninety-four percent of the vaccinated chickens (353 birds) with a B-ELISA value above 60% were protected. A strong positive correlation (0.934) was found between 'actual protection' (protection against challenge) and 'estimated protection' (protection calculated from the B-ELISA results). Based upon the results obtained, this B-ELISA seems to be suitable for replacing the challenge test in the potency control of inactivated ND vaccines in the future.

[Percutaneous endoscopic gastrostomy: experience of three years]

Patients who are not able to eat do need tube feeding. The most preferred way of artificial enteral nutritional support is feeding via percutaneous endoscopic gastrostomy (PEG) tubes. Head and neck cancer patients do represent a special group of patients needing a PEG. On the one hand at the time of admission to the hospital they are mainly undernourished. On the other hand the failure rate of placing a PEG is the highest among them. Furthermore in the perioperative period nasogastric tubes do cause a lot of complications in these settings. 188 PEG placements were carried out from July 1995 till November 1998.

INDICATIONS

head and neck cancer (n = 171), neurologic disorders (n = 17). PEG tubes were placed 76 times during intratracheal narcosis and 112 times following local anaesthesia. 39 times there was a prior abdominal surgery in our patients medical history. The pull-through, the push-wire and the introducer techniques were used. Beside the usual oro-gastric way of endoscopying (n = 163), 25 times the following alternative ways of entering the upper gastrointestinal tract were used: transnasal route (n = 4), through a Kleinsasser type direct laryngoscope (n = 7) and via the opened pharynx (n = 14). No immediate or late onset procedure related complications occurred. During a follow-up of 22,480 tubedays 26 minor (dermatitis n = 24, ulcer n = 2) and 8 major (abscess n = 4, perforation/peritonitis n = 3, stomach and bowel wall necrosis n = 1) complications occurred. The success rate of placing a PEG was 98.9%. In head and neck cancer patients placing a PEG is suggested when there is a need for at least a 7 days time tube-feeding. Using the described alternative ways, a PEG tube can be placed almost always. Because of the uncertain outcome, nutritional support via PEG tubes is suggested also in cachectic patients and in vegetative state as well.

Binding of girisopam (a 2,3-benzodiazepine derivative) to the substantia nigra is prevented by lesioning of the striatonigral pathway

The binding sites of girisopam, a homophthalazine (2,3-benzodiazepine)-derivate have a specific distribution pattern restricted to the striato-pallido-nigral system of the rat brain. Following kainic acid lesions in the caudate-putamen or the ventral striatum (nucleus accumbens, olfactory tubercle), as well as after surgical transection of the striatonigral pathway, [3H]girisopam binding sites were reduced or completely eliminated from the substantia nigra and the entopeduncular nucleus. Kainic acid lesions of the globus pallidus failed to act on girisopam binding sites in the substantia nigra. Surgical transections or 6-hydroxydopamine lesions of the striatonigral pathway, as well as intranigral kainic acid injections did not influence binding sites in the striatum or the pallidum. These findings indicate that girisopam in the striatum to be postsynaptic on striatonigral projecting neurons. Girisopam in the striatum seems is present in striatonigral projecting neurons. The binding sites are transported from the striatum (mainly from the caudate-putamen, partly from the ventral striatum) to the substantia nigra and the entopeduncular nucleus. The exact identity of these striatonigral fibres bearing homopthalazines is uncertain.

Sensorimotor impairments in rats with cerebral infarction, induced by unilateral occlusion of the left middle cerebral artery: strain differences and effects of the occlusion site

Enormous differences exist between rat strains with respect to the infarct volume induced by unilateral middle cerebral artery (MCA) occlusion. We performed three experiments to address the following questions. Firstly, whether the pattern of MCA-occlusion (MCA-O) induced sensorimotor impairments in rats are strain dependent; secondly, whether proximal (i.e., close to its origin) and distal occlusions (above the lenticulostriate branch) of the MCA affect infarct volume and the behavioral impairments to a different extent; and thirdly, whether there is a relationship between the infarct volume and behavioral deficits. We found that the pattern of sensorimotor malfunctions induced by proximal unilateral MCA-O were highly strain dependent. Of the eight strains tested, Winkelmann-Wistar rats, Spontaneously Hypertensive Stroke-Prone rats, and Wistar-Kyoto rats were most severely affected. By contrast, Brown-Norway rats showed only mild behavioral deficits after the MCA-O. The second experiment confirmed that proximal occlusions induced slightly more behavioral malfunctions than distal occlusions did. Histological evaluation of the brain damage caused by proximal and distal MCA-O, confirmed that distal MCA-O damaged nearly exclusively cortical areas, and spared the caudate/putamen. An exploratory analysis of the relationship between infarct volume and behavioral deficits did not indicate that the severity of sensorimotor malfunctions can be predicted from the size of the infarct.

Sensorimotor impairments in Wistar Kyoto rats with cerebral infarction, induced by unilateral occlusion of the middle cerebral artery: recovery of function

Wistar Kyoto (WKY) rats with cerebral infarction induced by permanent unilateral occlusion of the middle cerebral artery (MCA) and sham-operated rats were tested in a series of simple behavioral test 2, 16 and 37 days after surgery. In addition, the motility of the animals was measured over a period of 62 h, after the third test series. A subset of the tests appeared to be suitable to assess the effects of cerebral infarction, namely, grasping reflex of contralateral hindpaw, circling behavior, forelimb flexion, hindlimb flexion, and latency to fall off a square bridge. Except for the impaired grasping reflex of the contralateral hindpaw, there was spontaneous complete recovery of function by the third test session, 37 days after surgery. Some of the other tests might not have been sensitive enough to detect the effects of the unilateral MCA-occlusion (MCA-O) on behavior. Moreover, the WKY rats were very inactive in some of the tests, so that reliable scoring of the effects was not always possible. A rat strain other than the WKY strain might be more suitable to study the behavioral consequences of MCA-O.

Functional cerebral activity during regeneration from entorhinal lesions in the rat

The consequences of an unilateral electrolytic entorhinal lesion on the functional activity in all major anatomically defined brain regions were evaluated in the rat. The 14C-2 deoxyglucose method served as a tool to quantify alterations of local cerebral glucose utilization (LCGU) ipsilateral and contralateral to the lesion at 4 days, 2 weeks, or 3 months after stereotaxic surgery. Apart from a few minor increases in the contralateral hemisphere, the predominant pattern consisted of reductions in the range of 10-40% in the ipsilateral hemisphere. Ipsilaterally, in extrahippocampal areas, LCGU had regained control levels at 2 weeks postlesion in contrast to hippocampal regions, where reductions were more pronounced than in other brain areas and partially persisted for up to 3 months. Interestingly, the termination zones of entorhinal fibers in the dentate gyrus did not regain control levels within 3 months. We conclude from the data that functional recovery of denervated primary target areas does not occur within 3 months after entorhinal lesions and that altered functional activity may be found beyond the primary target areas predominantly during the acute recovery period after the lesion. The data suggest that sprouting fibers do not reestablish a fully functional neuronal network during the recovery period.

Correlation between retention behaviour and GC-FTIR data in the study of flavonoids

Trimethylsilyl derivatives of 10 different hydroxy- and methoxyhydroxyflavonoid compounds were studied by the GC-FTIR technique. Optimal deviation parameters were determined for the flavonoids studied. The correlation found between retention and gas-phase IR data can successfully be used in structural identification of compounds having very similar chromatographic behaviour. The shift of the carbonyl frequency gives information on the presence of substituting agents.

[Comparative study of antibiotic use at hospital departments in 7 Hungarian hospitals 1989-1991]

In their present work, authors, referring to their previous paper, wanted to compare the antibiotic consumption of the special medical fields in different hospitals. Computer database were utilised from different hospitals to obtain the necessary figures concerning antibiotic consumption. The amount of antibiotic consumption was expressed in Defined Daily Dose/1000 hospital day. The great differences found between hospitals in quality of antibiotic consumption related to the same subspeciality can be due to the different therapeutical approach in the respective departments. Quality of drug utilisation did not meet the expectations of the modern antibiotic therapy. Relatively low consumption was found in departments of ophthalmology, neurology, psychiatry and rehabilitation. Medium amount of antibiotic consumption was recorded in departments of internal medicine, general surgery, traumatology, obstetrics and gynecology, E. N. T. and dermatology. High antibiotic consumption was observed at the departments of urology, intensive care, infectology, pediatrics and pulmonology. Authors emphasise the importance of the education of the usage of antibiotics both at the medical universities and in postgraduate training as well.

[Comparative study of antibiotic consumption in Hungarian hospitals during 1989-1991]

The data of case histories of the year of 1989 of seven Hungarian hospitals and also the 1990 and 1991 data of two hospitals were collected and integrated in a database. Consumption of antibiotics were represented in DDD (Defined Daily Dose)/1000 hospital day. These data were compared with the data of the drugs delivered by the hospital pharmacy in one of the mentioned hospitals between 1989 and 1992. It was concluded that data based on case histories represent better the real antibiotic consumption than those of the hospital pharmacy. Reason of this phenomenon is the fact, that considerable amount of drug supply gets out of institutions. Great differences were observed between the seven hospitals in the total amount of antibiotic consumption and between the different antibiotic groups as well. Drugs most frequently used were tetracyclines, broad spectrum penicillins, sulfonamides and aminoglycosides. Consumption of penicillins was decreasing. Regarding new drugs only utilisation of quinolones was increasing. It was concluded, that structure of antibiotic selection did not follow the recommendations of the medical literature. The authors suggest that "antibiotic policy" should be introduced in Hungarian hospitals so as to imporve antibiotic utilisation.

Glutamate dehydrogenase in astrocytes of the rat dentate gyrus following lesion of the entorhinal cortex

Applying quantitative microscopic histochemistry, the activity of the mitochondrial glutamate dehydrogenase which is localized in astrocytes was determined in the molecular layer of the dentate gyrus of the rat hippocampus. This hippocampal region contains the important terminations of the glutamatergic perforant path. For comparison, determinations of the mitochondrial succinate dehydrogenase were performed, which is localized preferentially in terminals and dendrites. Two age groups of animals were examined: young adults (three months old) and aged subjects (24 months old). Both age groups were divided into controls, and animals killed three, 21 and 90 days following unilateral electrolytic lesion of the entorhinal cortex. The post-lesional shrinkage of the terminal field of the perforant path, ipsilateral to the lesion side, was determined and considered in the evaluation of enzymatic data. Statistic analysis revealed that ipsilateral to the lesion side there was a significant decrease of glutamate and succinate dehydrogenase activities in the terminal field of the perforant path three, 21 and 90 days following lesion. It is reasonable to assume that the decrease of succinate dehydrogenase activity (50-60%) was caused by the loss of mitochondria localized in degenerating terminals, whereas the decrease of glutamate dehydrogenase activity (20-30%) was related to the decrease of glutamatergic transmission following lesion. In the terminal field of the perforant path contralateral to the lesion side both significant increases and decreases of enzyme activities were measured following lesion. From these results it is concluded that the hippocampus contralateral to the lesion side cannot be considered as an appropriate intraindividual control. The comparison between young and aged animals showed no differences in the demonstration of glutamate dehydrogenase and only restricted differences in the activity level of succinate dehydrogenase post-lesion. Therefore, it is reasonable to assume that the post-lesional reactivity of the enzymes studied was very similar in both age groups.

[Specific enzyme diagnosis in mitochondrial myopathies and encephalomyopathies]

Mitochondrial enzyme activities (cytochrome c-oxidase = COX, carnitine acyl-transferase = CAT, citrate synthase = CS, lipoamide dehydrogenase = lipDH from the pyruvate-dehydrogenase complex, lactate dehydrogenase = LDH, and malate-dehydrogenase = MDH) were measured from progressive myopathy/encephalomyopathy. Cytochrome oxidase (COX) deficiency was detected from muscle or liver tissues, adult type of COX defectus had been diagnosed in 1 case and infantile type in further 6 cases. The 3 familial atactic children showed decreased activity of carnitine acetyl-transferase, too.

Determination of oxytetracycline and its decomposition products in Tetran vulnerary powder

A simple and fast HPLC method was developed for the determination of oxytetracycline and its decomposition products in pharmaceutical preparations. For this purpose an octadecyl modified silica stationary phase and a terner eluent containing aceto-nitrile-methanol-aqueous oxalic acid/EDTA solution was employed. Using this method, a stability study of oxytetracycline-containing powder was carried out. In this paper the analytical method and its performance data, the sample preparation and the obtained stability data are presented. The literature published on this topic is also shortly overviewed and discussed.

Acetylcholinesterase activity and post-lesional plasticity in the hippocampus of young and aged rats

Applying quantitative microscopic histochemistry, the activity of acetylcholinesterase was determined in the various layers of the rat hippocampus at three different levels along the rostrocaudal extent. Two age groups of animals were examined: young adults (two to three months old) and aged subjects (26 months old). Young adults were divided into controls, and animals killed eight and 35 days following bilateral ibotenate lesioning of the medial septum-diagonal band complex. Aged rats were divided into controls and animals 35 days post-lesion. Analysis of variance revealed that the mean acetylcholinesterase activities of the entire hippocampus of individuals were not significantly different between young and aged rats when averaged across controls and 35 days post-lesion. There was a significant decrease of acetylcholinesterase activity (-52%) in young adults eight days post-lesion as compared to controls, but a significant increase (+63%) took place until 35 days post-lesion as compared to eight days post-lesion. Significantly lower activities existed, however, in young (-22%) and aged rats (-18%) 35 days post-lesion as compared to controls. This decrease in mean activity was not age dependent. As acetylcholinesterase is considered to be a good cholinergic indicator in the hippocampus, the results suggest a homotypic collateral sprouting from spared cholinergic afferents following ibotenate lesion of the medial septum-diagonal band complex in young and aged rats. Based on the data obtained, it is reasonable to assume that there was no difference in the post-lesional plasticity of neuronal acetylcholinesterase between young adult and aged rats.

Chloroplast transformation in plants: polyethylene glycol (PEG) treatment of protoplasts is an alternative to biolistic delivery systems

Nicotiana plumbaginifolia protoplasts were directly transformed by PEG treatment with a cloned 16S rRNA gene isolated from a double antibiotic-resistant Nicotiana tabacum plastid mutant. Putative plastid transformants were selected in cell culture by their spectinomycin resistance and identified by their unselected streptomycin resistance. Alternatively, cell lines were selected in the presence of both antibiotics. The cell line (and its regenerated plants) selected solely for spectinomycin resistance demonstrated an extensive segregation of streptomycin resistance in subsequent tests, while the double-selected line showed stable resistance for both antibiotics. The resistance markers were inherited maternally. In the putative plastid transformants the origin of the resistance mutations was identified by the absence of an AatII site, missing in the donor N. tabacum plastid gene (spectinomycin resistance site) but present in that of wild-type N. plumbaginifolia, and a sequence analysis of the particular nucleotide changes in both resistance sites. Restriction enzyme analysis of total plastid DNA (ptDNA), and the recloning and full sequencing of the fragment introduced, investigated in one of the plastid transformants, showed no DNA rearrangements accompanied with the integration process. Sequence analysis indicated a targeted, homologous integration of the DNA fragment introduced but an unexpectedly complete homology of the parental ptDNA sequences in this region prevented the location of borders. Although the frequency of plastid transformant colonies (2 x 10(-5)) should still be improved, this method for stable chloroplast DNA transformation is comparable with or more efficient than the particle bombardment techniques.

Chloroplast transformation in plants: polyethylene glycol (PEG) treatment of protoplasts is an alternative to biolistic delivery systems

Nicotiana plumbaginifolia protoplasts were directly transformed by PEG treatment with a cloned 16S rRNA gene isolated from a double antibiotic-resistant Nicotiana tabacum plastid mutant. Putative plastid transformants were selected in cell culture by their spectinomycin resistance and identified by their unselected streptomycin resistance. Alternatively, cell lines were selected in the presence of both antibiotics. The cell line (and its regenerated plants) selected solely for spectinomycin resistance demonstrated an extensive segregation of streptomycin resistance in subsequent tests, while the double-selected line showed stable resistance for both antibiotics. The resistance markers were inherited maternally. In the putative plastid transformants the origin of the resistance mutations was identified by the absence of an AatII site, missing in the donor N. tabacum plastid gene (spectinomycin resistance site) but present in that of wild-type N. plumbaginifolia, and a sequence analysis of the particular nucleotide changes in both resistance sites. Restriction enzyme analysis of total plastid DNA (ptDNA), and the recloning and full sequencing of the fragment introduced, investigated in one of the plastid transformants, showed no DNA rearrangements accompanied with the integration process. Sequence analysis indicated a targeted, homologous integration of the DNA fragment introduced but an unexpectedly complete homology of the parental ptDNA sequences in this region prevented the location of borders. Although the frequency of plastid transformant colonies (2 x 10(-5)) should still be improved, this method for stable chloroplast DNA transformation is comparable with or more efficient than the particle bombardment techniques.

[Informative value of varying serum alpha fetoprotein levels in pregnant women based on a screening program in a Hungarian institute. What next?]

The authors evaluated the maternal serum alfa fetoprotein screening data of 3 years period. Out the neural tube defects they observed increased values at 20% of another congenital malformations. At the pregnant having abnormal serum alfa fetoprotein significantly accumulated the late-term abortion, stillbirth and preterm delivery. At the mothers of stillborns and abortions frequently noticed the different values. They direct attention to the fetal-living-danger importance, control functions of the abnormal level and after prospective data collection it may have new aspecific alarm role too. Accordingly the maternal serum alfa fetoprotein may consider like fetal blood sediment examination.

Effects of the 1,4-dihydropyridine-sensitive L-type calcium channel antagonist nimodipine and calcium channel activator Bay K 8644 on local cerebral glucose utilization in the rat

The quantitative [14C]-2-deoxy-D-glucose autoradiographic method was used to compare the acute effects of the Ca2+ channel antagonist nimodipine (10 mg/kg) and the Ca2+ channel activator Bay K 8644 (1.25 mg/kg) on local cerebral glucose utilization of rat brain after single, intraperitoneal application. Nimodipine reduced glucose metabolism significantly in 23 of the 49 brain regions evaluated. Bay K 8644 decreased the local cerebral glucose utilization to an even greater extent in all regions studied. The anatomic localization of those regions with the largest decrease of glucose utilization was almost identical for both drugs (globus pallidus, hippocampus, geniculate body, substantia nigra, and entorhinal cortex). No increase in glucose metabolism was measured in any of the brain areas evaluated.

Effects of 5-hydroxytryptamine1A-receptor agonists on hippocampal damage after transient forebrain ischemia in the Mongolian gerbil

The activation of 5-hydroxytryptamine receptors exerts an inhibitory influence on neuronal activity in a way similar to the activation gamma-amino-n-butyric acid and adenosine A1 receptors. Therefore, we hypothesized that 5-HT1A-receptor agonists might exert a neuroprotective effect. We tested the full agonists Bay R 1531 and 8-OH-DPAT and the partial agonists ipsapirone and gepirone in the model of transient global ischemia in the Mongolian gerbil. Ipsapirone protected 53% of pyramidal neurons (p less than 0.05) in the CA1 area of the hippocampus from ischemic damage at a dose of 3 mg/kg. Bay R 1531 showed a powerful neuroprotective effect with 100% preservation of neurons at a dose of 3 mg/kg (p less than 0.001) while gepirone and 8-OH-DPAT were ineffective. These findings suggest that 5-HT1A-receptor agonists might be effective tools for the therapy of cerebral ischemia. However, the varying results indicate that transient forebrain ischemia in the gerbil may not be the optimal model system to demonstrate clearly the neuroprotective activity of these compounds.

Effects of early onset of nimodipine treatment on microvascular integrity in the aging rat brain

We studied the effects of long-term treatment with 1,4-dihydropyridine nimodipine on age-related changes of the cerebral microvasculature in layers I, III, and V of the frontoparietal motor cortex of aged (30 months) male Wistar rats. Ultrastructural alterations of microvessels can either be attributed to degeneration or to deposition processes. Nimodipine application, irrespective of the time of onset, did not interfere with the degeneration of microvascular pericytes. However, nimodipine treatment from 24-30 months significantly reduced the amount of microvascular deposition products in cortical layers I and III, while an earlier onset (16 months) of the drug application resulted in a significant reduction in all motor cortex layers studied. This indicates a different susceptibility of microvessels in layer V of the frontoparietal motor cortex. These results show a beneficial effect of nimodipine on the integrity of cerebral microvasculature during aging and may provide a morphologic basis for the improved motor and cognitive performance in aged rats after chronic nimodipine application.

Synthesis of a gene for human serum albumin and its expression in Saccharomyces cerevisiae

A 1761 base pairs long artificial gene coding for human serum albumin (HSA) has been prepared by a newly developed synthetic approach, resulting in the largest synthetic gene so far described. Oligonucleotides corresponding to only one strand of the HSA gene were prepared by chemical synthesis, while the complementary strand was obtained by a combination of enzymatic and cloning steps. 24 synthetic, 69-85 nucleotides long oligonucleotides covering the major part of the HSA gene (41-1761 nucleotides) were used as building blocks. Generally, four groups of 6-6 such oligonucleotides were successively cloned in pUC19 Escherichia coli vector to obtain about quarters of the gene as large fragments. Joining of these four fragments resulted in a cloned DNA coding for the 13-585 amino acid region of HSA, which was further supplemented with a double-stranded linker sequence coding for the amino terminal 12 amino acids. The completed structural gene composed of frequently used codons in the highly expressed yeast genes was then supplied with yeast regulatory sequences and the HSA expression cassette so obtained was inserted into an Escherichia coli-Saccharomyces cerevisiae shuttle vector. This vector was shown to direct the expression in Saccharomyces cerevisiae of correctly processed, mature HSA which was recognized by antiserum to HSA, and possessed the correct N-terminal amino acid sequence.

[Mammosomatotropic cells in the pituitary gland of the rat with and without adenoma. Immunoelectron microscopic study]

In non-tumorous adenohypophysis and in adenomas of adenohypophysis of rats the GN and PRL producing bihormonal mammosomatotroph cells were demonstrated by double marked immune-gold immuno-electronmicroscopic examinations. Cytogenesis and regulation of these cells are known, their clearing up is expected. Further examinations are needed to elicit, whether mammosototroph cells may occur also in nontumorous human adenohypophysises.

Acute effects of cadmium on preovulatory serum FSH, LH, and prolactin levels and on ovulation and ovarian hormone secretion in estrous rats

On the day of diestrus II CFY rats were given 5, 10, or 15 mg/kg cadmium chloride (CdCl2) or 1.0 mL/kg of 0.9% NaCl. On the next day a group of animals was anesthetized with pentobarbital and blood was collected from the aorta at 13:00, 15:00, 16:30, or 18:00 h. for FSH, LH, prolactin (PRL), progesterone (P), and estradiol-17 beta (E2) determination. On the day of the expected estrus, the second group of animals was anesthetized with pentobarbital and cannulas were inserted in one of the femoral arteries and veins, and in one of the utero-ovarian veins. Five-minute blood fractions were collected from the ovary for 40 min, and following the first blood samples, 10 IU hCG was injected iv. Ovarian venous outflow and blood pressure were continuously recorded. From the blood fractions, P and E2 were determined, and their secretion rates were calculated. In a third group of treated animals, the ovaries were excised for histological examination, and oviducts were flushed for counting oocytes. CdCl2 in the dose of 10 or 15 mg/kg increased the PRL serum levels at 13:00 h; it diminished FSH serum levels in the dose of 10 mg/kg and LH serum levels in the doses of 10 and 15 mg/kg at 15:00 h. The decrease in LH levels continued until 16:30 h in the dose of 10 mg/kg CdCl2. In estrous animals, CdCl2 did not influence the blood pressure and ovarian blood flow. In animals receiving 10 or 15 mg/kg CdCl2, a decrease in basal secretion of P occurred.(ABSTRACT TRUNCATED AT 250 WORDS)

Construction of versatile Escherichia coli--yeast shuttle vectors for promoter testing in Saccharomyces cerevisiae

The promoterless PHO5 gene of the yeast Saccharomyces cerevisiae, encoding the repressible acid phosphatase (AP) was utilized as a reporter gene for the construction of a novel vector system for selection and functional analysis of yeast promoters. The Escherichia coli-yeast shuttle plasmids, pZHB81 and pZHB82, contain different arrays of unique restriction sites located upstream of the PHO5 coding region. Yeast promoters could be screened from random DNA fragments (cloned in the upstream sites) for their ability to direct the expression of the PHO5 gene in transformed (AP-deficient) yeast host cells. AP-expressing transformants were selected directly on agar plates by using a routine colony staining method. Relative promoter strength was assessed by direct assay for AP activity in cell lysates.

GTP effects in rat brain slices support the non-interconvertability of M1 and M2 muscarinic acetylcholine receptors

GTP (guanosine-5'-triphosphate) markedly reduced high-affinity 3H-oxotremorine-M binding to M2 receptors on brain slices in autoradiographic experiments while 3H-pirenzepine binding to M1 receptors was largely unaffected. The distribution of M1 receptors so labelled was also not altered by GTP to include former M2-rich regions, thus indicating that GTP could not, by itself, interconvert high agonist-affinity M2 receptors to M1 receptors.

Effect of the 5-HT1A receptor agonist ipsapirone on the local cerebral glucose utilization of the rat hippocampus

Local cerebral glucose utilization (LCGU) was measured in the hippocampus of the rat brain following i.p. injection of the anxiolytic drug and 5-HT1A receptor agonist ipsapirone (TVX Q 7821). Administration of ipsapirone (5 mg/kg) reduced glucose utilization in the various hippocampal areas to variable extent. The most subtle reduction took place in the dorsal subiculum, while the most pronounced decrease was found in sector CA4 of Ammon's horn. The degree of LCGU reduction can be related to the 5-HT1A receptor density in the respective areas.

Effects of N-ethylmaleimide on muscarinic acetylcholine receptor subtype autoradiography and inositide response in rat brain

Chemical modification of brain muscarinic acetylcholine receptors (mAChr) with N-ethylmaleimide (NEM) has been employed to investigate mAChr-subtype distribution and mediation of the inositide response. 3H-Pirenzepine and 3H-oxotremorine-M were used to autoradiographically localize the M1- and M2-AChr subtypes, respectively, in brain slices. M1- and M2-AChr distribution were observed to be distinct from each other. The presence of 1 mM NEM selectively reduced the labeling of M2-, but not of M1-AChr. These data support the notion that NEM converts the high-affinity M2-AChr to a lower affinity state, without affecting the affinity of the M1-AChr. Also, regional analysis indicated that the M1- and M2-AChr subtypes were not interconvertible by NEM. NEM at 30 microM enhanced the carbamylcholine stimulated labeling of phosphatidic acid from 32Pi in nerve endings from rat forebrain, suggesting that the low affinity M2-AChr may mediate at least a part of the inositide response to cholinergic stimulation.

Direct autoradiographic determination of M1 and M2 muscarinic acetylcholine receptor distribution in the rat brain: relation to cholinergic nuclei and projections

The autoradiographic distributions of receptors with high affinity for [3H]oxotremorine-M (the M2 receptor) and [3H]pirenzepine (the M1 receptor) were studied in the rat brain. M1 receptors were seen in highest density only in telencephalic structures: cerebral cortex (layers I-II), hippocampus, dentate gyrus, medial and basolateral amygdala, nucleus accumbens and caudate/putamen. M2 receptors were detected throughout the brain, with highest levels observed in cerebral cortical layers III and V, forebrain cholinergic nuclei, caudate/putamen, various thalamic areas, inferior and superior colliculus, interpeduncular and pontine nuclei, brainstem cholinergic nuclei and cervical spinal cord regions. M2 receptors were found to be good markers for cholinergic cell groups and the majority of cholinergic projection areas, whereas M1 receptors were only found in a large sub-group of telencephalic cholinergic projection areas, and the pattern of distribution of receptors in these areas differed from that of M2 receptors. Scatchard analysis of [3H]oxotremorine-M binding to inferior collicular slices revealed one site with a dissociation constant (Kd) of 1.9 nM and a receptor density (Bmax) of 1.4 pmol/mg protein. Our data support the hypothesis that M1 and M2 receptors are physically distinct sub-types of the muscarinic acetylcholine receptor.