Immunohistochemical features of paragangliomas

Immunohistochemistry is part of the routine diagnosis of the neuroendocrine tumors. In our study, we included 52 paragangliomas with various localizations by routine histology and immunohistochemistry. In order to increase the diagnostic specificity, a complex immunohistochemistry panel has been performed consisting of Bcl-2, Ki-67, Bax and Pituitary Adenylate Cyclase-Activating Peptide (PACAP), somatostatin, VIP and Calcitonin Gene Related Peptide (CGRP). After heat induced antigen retrieval, the immunostaining was performed by StreptABC using DAB as a chromogen. We were the first to demonstrate the presence of Bax and PACAP in paragangliomas. Some of the used markers are of prognostic value. The relationship between Bcl-2 and Bax is decisive in generating the final response to the input apoptotic signals. The Ki-67 antigen staining has gained wide acceptance in prognostic evaluation of other tumor types. We noted a small number of Ki-67 positive cases, which signifies a low mitotic activity of these tumors and a relatively high number of Bax positivities (32.9%) and the much lower number of Bcl-2 positivities (11.39%), and could explain the benign behaviour of paragangliomas.

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

The glutamate transporters GLT-1 and GLAST localized in astrocytes are essential in limiting transmitter signalling and restricting harmful receptor overstimulation. To show changes in the expression of both transporters following lesion of the entorhinal cortex (and degeneration of the glutamatergic tractus perforans), quantitative microscopic in situ hybridization (ISH) using alkaline-phosphatase-labelled oligonucleotide probes was applied to the outer molecular layer of the hippocampal dentate gyrus of rats (termination field of the tractus perforans). Four groups of rats were studied: sham-operated controls, and animals 3, 14 and 60 days following unilateral electrolytic lesion of the entorhinal cortex. The postlesional shrinkage of the terminal field of the perforant path, ipsilateral to the lesion side, was determined and considered in the evaluation of quantitative ISH data. Statistical analysis revealed that ipsilateral to the lesion side there was a significant decrease of the GLT-1 mRNA at every postlesional time-point and of the GLAST mRNA at 14 and 60 days postlesion. The maximal decrease was approximately 45% for GLT-1 and approximately 35% for GLAST. In the terminal field of the perforant path contralateral to the lesion side, no significant changes of ISH labelling were measured. The results were complemented by immunocytochemical data achieved using antibodies against synthetic GLT-1 and GLAST peptides. In accordance with ISH results, there was an obvious decrease of GLT-1 and GLAST immunostaining in the terminal field of the perforant path ipsilateral to the lesion side. From these data we conclude that, following a lesioning of the entorhinal cortex, the loss of glutamatergic synapses in the terminal field of the perforant path resulted in a strong downregulation of glutamate transporters in astrocytes. The decrease of synaptically released glutamate or of other neuronal factors could be involved in this downregulation.

Fetomaternal transfusion and pregnancy outcome after cordocentesis

OBJECTIVE

To study the extent of fetomaternal transfusion and the outcome of pregnancy after cordocentesis.

MATERIAL AND METHODS

268 women underwent percutaneous fetal umbilical cord blood sampling for fetal karyotyping between 15 and 26 gestations of weeks. Complete follow-up was available in 221 (82.5%) of the cases. Cordocentesis was performed under continuous real-time ultrasound guidance. The duration of the procedure and the post-procedural bleeding time was counted in seconds. Fetomaternal transfusion was calculated by using the measurements of the maternal serum levels of alpha-fetoprotein before and after the procedure. The data were analyzed by Student's t and multiple regression tests.

RESULTS

The maximum and mean amounts of fetomaternal transfusion were 1.067 and 0.061 ml, respectively. Twenty percent or more alpha-fetoprotein elevation was in 35.4% of the cases. Positive correlation was found between bleeding time after cordocentesis and fetomaternal transfusion (r = 0.174, p < 0.0129) as well as between the duration of the procedure (r = 0.165, p < 0.0171) and the amount of fetomaternal transfusion. Comparing the cordocentesis at the placental insertion site and at the free cord loop, a smaller amount of fetomaternal transfusion was observed (p < 0.0123) in the latter. Transplacental passage was associated with a higher amount of fetomaternal transfusion (p < 0.0067). No association was found between the extent of fetomaternal transfusion and the outcome of pregnancy. The fetal loss related to the cordocentesis was 0.50%.

CONCLUSIONS

The extent of fetomaternal transfusion was influenced by the subsequent four parameters: procedural time, bleeding time, puncture site and transplacental penetration. The lack of the association between the degree of fetomaternal transfusion and the outcome of pregnancy, along with the low (0.50%) post-procedural fetal loss rate, suggest that cordocentesis is clinically a safe procedure.

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.