József Géza Kiss

ALA (5-aminolevulinic acid)-induced protoporphyrin IX fluorescence in the endoscopic diagnostic and control of pharyngo-laryngeal cancer.

Photodynamic diagnosis is a modern method for the fluorescence imaging of superficial pharyngeal and laryngeal tumours. 5-aminolevulinic acid (ALA)-induced protoporphyrin IX fluorescence benefits the tumour selective accumulation of protoporphyrin; therefore, tumours can be differentiated from healthy tissue. ALA-induced fluorescence of laryngo-pharyngeal tumours and precancerous and benign lesions were evaluated by endoscopy. At the Department of Otorhinolaryngology, Head and Neck Surgery, Szeged, Hungary, 31 patients underwent ALA-induced protoporphyrin fluorescence imaging. After topical application of ALA, mesopharyngeal tumours were visualised by direct fluorescence endoscopy. Laryngeal and hypopharyngeal tumours were examined with a laryngomicroscope with the patients under general anaesthesia after inhalation of an ALA solution. Intensity of PPIX fluorescence was classified and compared with pathological findings. The examination of all 13 laryngeal and 12 pharyngeal tumours resulted in a middle or strong intensity of red fluorescence, but for one cancer, four praecancerous and two benign lesions. Healthy tissues showed green autofluorescence. Margins of mesopharyngeal and vocal cord tumours were clearly outlined under fluorescent vision, giving a helpful contribution to diagnosis and therapy even in clinically non-visible tumours. Laryngomicroscopy combined with laser surgery also indicated PPIX fluorescence examination visualising margins of the tumour intermediately with the endoscope. The ALA-induced PPIX fluorescence imaging method revealed a sensitivity of 96%. This method is applicable for detecting early superficial tumours, margins of tumours and follow-up after surgery/radiation therapy in the laryngo-pharynx.

Endogenous vasopressin increases acute endotoxin shock-provoked gastrointestinal mucosal injury in the rat.

Administration of a low dose of endotoxin (from Escherichia coli, 3 mg kg(-1), i.v.), which does not affect vascular permeability or blood pressure over 1 h, leads to the release of endogenous vasopressin and damage to the mucosal microvasculature. Thus, endogenous vasopressin could be involved in septic shock. In the present study, we investigated the role of endogenous vasopressin in gastrointestinal mucosal injury induced by acute endotoxin shock, which was generated in rats by administering a high dose of E. coli endotoxin (50 mg kg(-1), i.v.). Tissues were removed 15 min after endotoxin. The vasopressin V1 receptor antagonist, d[CH2]5Tyr[Me]arginine-vasopressin (0.2-1 microg kg(-1), i.v.), was injected 10 min before endotoxin. Monastral blue (30 mg kg(-1), i.v.), which stains damaged vasculature, was injected 10 min before autopsy. Endotoxin reduced systemic arterial blood pressure (from 115+/-5 to 42+/-4 mmHg), generated macroscopic and microvascular injury, and elevated plasma vasopressin levels (from 3.4+/-0.2 to 178+/-16 pg ml(-1)). The vasopressin V1 receptor antagonist reduced this macroscopic injury, and in the vasopressin-deficient Brattleboro rat a similar reduction of gastrointestinal mucosal damage was found. Substantial decreases in endotoxin-induced microvascular damage were observed in each tissue, e.g., the gastric Monastral blue staining was reduced by 47+/-3% and 96+/-3% (P < 0.01) after vasopressin V1 receptor antagonist treatment and in Brattleboro rats, respectively. Vasopressin, acting through its V1 receptors, thus appears to be involved in acute endotoxin shock-provoked gastrointestinal injury.

Si etching affected by ir laser irradiation

Silicon was etched in an aqueous solution of sodium hydroxide under ir laser irradiation. Two types of lasers were used, a Nd:YAG laser with a wavelength of λ=1.06 μm and a CO2 laser with λ=10.6 μm. Small-size blind holes, through holes and reliefs were formed on a Si target, and even a special type of hole can be formed with help of a CO2 laser, namely a blind hole with a hillock in its center.

Two subgroups of schizophrenia identified by systematic cognitive neuropsychiatric mapping

The description of the heterogeneous phenomenological, pathophysiological, and etiological nature of schizophrenia is under way; however, the relationships between heterogeneity levels are still unclear. We performed a robust cross-sectional study, including a systematic neuropsychological battery, assessment of clinical symptoms, neurological soft signs, morphogenetic anomalies and smell identification, and measurement of event-related potentials on 50 outpatients with schizophrenia in their compensated states. An explorative fuzzy cluster analysis revealed two subgroups in this sample that could be distinguished from each other on symptomatological, cognitive and neurological levels. The patterns of cognitive dysfunctions and neurological developmental anomalies equally indicate that there may be hemispherical differences between the patients belonging to the different clusters.

Vasopressin deficiency decreases the frequency of gastroduodenal ulceration in humans

Vasopressin is a stress hormone released from the posterior pituitary. In humans suffering from central diabetes insipidus, this release of vasopressin is diminished. It was shown previously that the congenitally vasopressin-deficient Brattleboro homozygous rat is less sensitive to various ulcerogenic stimuli. In this study, we investigated the incidence of gastroduodenal ulceration in vasopressin deficient patients. Data on patients aged 20-70, hospitalized in Hungary between 1992 and 1995 were compared with those on the total population in this age group (6,681,020 in 1994). Subjects with central diabetes insipidus were selected separately (815 cases). Gastroduodenal ulceration was compared in subjects with an intact vasopressin release and vasopressin-deficient patients. The frequencies of gastroduodenal ulceration were also examined separately in male and female subjects. In the total population, the frequency of gastroduodenal ulceration was lower in vasopressin-deficient cases (2.22% versus 0.61%; P < 0.005). Among normal-vasopressin subjects, males have a higher risk of gastroduodenal ulceration than females (3.04% versus 1.46%, respectively; P < 0.001). Among vasopressin-deficient subjects, a similar male:female ratio was observed, but it was not significant (P = 0.36). In comparison to the normal-vasopressin population, the incidence of gastroduodenal ulceration was reduced among vasopressin-deficient males and females by 77% (P < 0.01) and by 82% (P < 0.05), respectively. In conclusion, endogenous vasopressin has a significant harmful action towards the human gastroduodenal mucosa. Peptide and non-peptide vasopressin receptor antagonists might have a potential therapeutic benefit in the treatment (as an adjuvant) and prevention of gastroduodenal ulceration.

Severity of Autonomic and Sensory Neuropathy and the Impairment of Visual- and Auditory-Evoked Potentials in Type 1 Diabetes: Is there a relationship?

It became clear in the last decades that neuropathy is not a separate clinical entity, but a component of several related complications (1). Although the functional consequences of neuropathy are well defined in various organ systems, the relationship of the alterations in the networks of the neuronal system is still poorly documented. Assessment of the potential common alterations of the different neuronal functions in patients with diabetic neuropathy may provide new pathogenetic and diagnostic considerations. Previously, we observed correlations between the delay of certain auditory-evoked potentials and the severity of autonomic and peripheral sensory neuropathy in patients with type 1 diabetes (2). In addition, we found a relationship between the latency of visual-evoked potentials and the peripheral neuronal function (3). The aims of this study were to analyze the possible correlations between the central auditory and visual afferentations and the severity of autonomic and sensory neuropathy in patients with long-standing type 1 diabetes. A total of 10 middle-aged type 1 diabetic patients …

Helicobacter pylori lipopolysaccharide-provoked injury to rat gastroduodenal microvasculature involves inducible nitric oxide synthase

The actions of a purified Helicobacter pylori lipopolysaccharide (3 mg x kg(-1), i.v.) on rat gastric antral and duodenal microvascular integrity (determined as radiolabelled albumin leakage) and the expression of the inducible nitric oxide (NO) synthase (iNOS; assessed by the citrulline assay) were investigated 4 h after challenge. Significant increases of albumin leakage and expression of iNOS in both antral and duodenal tissues were observed following challenge. Concurrent administration of the selective iNOS inhibitor, 1400W (N-(8-(aminomethyl)benzyl)-acetamidine; 0.2-1 mg x kg(-1), s.c.), with lipopolysaccharide, caused a dose-dependent attenuation of the gastric and duodenal albumin leakage. Thus, H. pylori lipopolysaccharide can initiate the expression of iNOS in the stomach and duodenum following systemic challenge, which can provoke gastroduodenal microvascular dysfunction.

Cathepsin-B activity in otosclerosis

SummaryCathepsin-B activity was determined fluorimetrically in the otosclerotic stapes footplate, the stapes superstructure, normal temporal cortical bone, and os frontale osteoma. Measurements with a synthetic substrate made determinations in individual samples possible. The cathepsin-B activity in the otosclerotic stapes footplate was one order of magnitude higher than that of the superstructure, which was not affected by the disease. The cortical bone and the superstructure displayed similar activities, as did os frontale osteoma and otosclerosis. The high lysosomal proteinase activity appears to be closely connected to the otosclerotic bone resorption process.

Inhibition of myosin light-chain kinase activity in the organ of Corti by 0.3–5 kilodalton substances of the otosclerotic perilymph

SummaryThe guinea pig organ of Corti contains myosin light-chain kinase (MLCK) activity. The upper and lowermost parts of the cochlea do not show significantly different activities of the enzyme, which is Ca2+ and calmodulin-dependent. Short-term noise exposure does not cause a significant change. 0.3–5 Kilodalton substances of the otosclerotic perilymph, separated by SG-25 column chromatography, inhibit the MLCK activity in in vitro organ of Corti preparations. This inhibitory action of the perilymph substances can also be observed with the purified MLCK of turkey gizzard. The activity of the enzyme can be specifically inhibited by cyclic AMP-dependent protein kinase.

Electrophysiological and99mTc-HMPAO-SPECT studies in Menkes disease

A diagnosis of Menkes kinky hair disease was made in two brothers who had typical clinical symptoms and laboratory findings. The older one, 11 months old at the time of diagnosis, showed an EEG pattern of low amplitude and slow waves. Visual evoked potentials (VEPs) were absent, brainstem auditory evoked potentials (BAEPs) were abnormal. Regional cerebral blood flow (rCBF) studied by hexamethylpropyleneamine oxime single photon emission computed tomography (99mTc-HMPAO-SPECT) revealed reduced blood flow in both frontal and the right temporal regions. The younger boy, followed from birth, started seizures at the age of 3 months and had a hypsarrhythmia-like EEG. BAEPs were abnormal with prolongation of the latencies at the age of 12 months, while VEPs were near normal at 6 months, but disappeared by the age of 18 months. 99mTc-HMPAO-SPECT revealed an unexpected left parietal hyperperfusion.