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K Nowak

Publications and source records attributed to K Nowak.

At least 55 records · Page 3Linked to original sources

Computer-aided analysis of the nuclear area in proliferative lesions of the colonic and bronchial epithelium.

The aim of this study was to establish the diagnostical value of nuclear area in proliferative lesions of colonic and bronchial epithelium. The study included 11 adenomas and 9 adenocarcinomas of colon, 11 control samples of normal colonic epithelium as well as 5 cases of bronchial squamous cell metaplasia, 25 squamous cell carcinomas, 9 small cell carcinomas and 3 adenocarcinomas of bronchi and 13 control samples of normal bronchial epithelium. All tissue samples were formalin fixed, paraffin embedded and silver stained. Morphometrical analysis was performed using optical Axiophot microscope with immersion, B/W CCD camera connected to frame grabber card, computer PC AT 386 and morphometrical software Vist and Morpho. Nuclear area was measured semiautomatically. Within each case 100 nuclei were analyzed. Statistically significant differences between carcinoma and adenoma or normal epithelium were observed in colon. In bronchi nuclear area was significantly higher in squamous cell carcinoma and adenocarcinoma if compared with other lesions including small cell carcinoma or bronchial metaplasia and normal epithelium.

Adenoma↗

Morphometric measurements of the nuclear area in proliferative thyroid lesions.

The aim of this study was to establish the diagnostic value of nuclear area in proliferative lesions of thyroid gland. This study included 98 histological preparations of thyroid and 57 cytological preparations (touch imprints). Morphometric analysis was performed using light microscopy, B/W CCD camera connected to the frame grabber card, computer PC AT 386/3 and morphometric software Vist and Morpho. Nuclear area was measured semiautomatically. Our study indicated that the nuclear area was significantly higher in cytological preparations and that size of nuclei seems to depend on the type of neoplasm and to a lesser extent on whether a given tumor was malignant or benign.

Adenoma↗

[Clinical importance of granulocyte-specific antibodies].

Clinical and laboratory data of 184 patients with immune neutropenia were evaluated. They suffered from autoimmune neutropenia (n = 165), alloimmune neonatal neutropenia (n = 18) and from transfusion-associated lung injury (n = 1). Autoimmune neutropenia was predominantly found in patients below 3 years. Patients were usually affected by benign bacterial infections. The peripheral blood count showed normal or diminished leukocyte counts with median absolute neutrophil counts of 285 cells/microliters. Bone marrow examination revealed in 60% of the cases a hypercellular marrow with a shift to the left. In 36% the bone marrow was normal and in 4% a hypocellular marrow was found. Spontaneous remission occurred in all newborns and, so far, in 4 patients with autoimmune neutropenia. Symptomatic treatment of the infections was sufficient in most of the patients.

Adolescent↗

Autoimmune neutropenia: clinical and laboratory studies in 143 patients.

Clinical and laboratory data of 143 patients with primary or secondary autoimmune neutropenia (AIN) were evaluated. Primary AIN was found predominantly in children below 3 years, whereas secondary AIN was more frequent in patients 40-60 years of age. Female patients with primary AIN were slightly more prevalent (54%) than male patients (46%). The peripheral blood count showed normal or diminished leukocyte counts with median absolute neutrophil counts of 250 cells/microliters. In 38% of the patients neutropenia was accompanied by monocytosis. Bone marrow examination revealed in 95% a normo- or hypercellular marrow with a marked reduction of mature neutrophils in 56% of the specimens. Twenty-three percent of the sera showed specificity for the NA1 antigen. Patients were usually affected by benign bacterial infections of the skin and of the upper respiratory tract, as well as by recurrent otitis media. Infections were treated symptomatically, and only six patients required continuous administration of antibiotics. Remission of neutropenia during treatment occurred in three of six patients treated with intravenous immunoglobulin G and in three of four patients who received steroid therapy. Except for one patient neutropenia relapsed after discontinuation of therapy. During a follow-up of 6-36 months, spontaneous remission has been observed in four patients.

Antibodies, Anti-Idiotypic↗

Immunohistology of gastrointestinal carcinoid tumors.

DAKO quick staining kits were used to immunostainings for Epithelial Membrane Antigen (EMA) Neuron Specific Enolase (NSE) and S-100 protein (S-100) in 18 carcinoid tumors of the gastrointestinal tract classified according to Soga and Tazawa. EMA was always absent in carcinoid tumors, being at the same time present within glandular epithelium. 88% of cases showed positive immunostaining for NSE. S-100 immunostaining showed immunopositive stellate cells present within the tumor especially within type A carcinoids. In addition in one carcinoid tumor thick, strongly S-100 positive bundles were noticed at the periphery of nests of tumor cells. Combined immunohistochemical and ultrastructural studies are needed to elucidate interrelation of neoplastic and neural elements within carcinoid tumorsa.

Adolescent↗

Conditioned behavioural responses to apomorphine: extinction and haloperidol-induced inhibition.

In previous studies it was established that stereotypies (sniffing, licking, gnawing) produced by apomorphine can be conditioned and after repeated pairings with defined conditioned stimuli (auditory, tactile + olfactory) these stereotypies can be observed in the presence of the conditioned stimuli alone. In the present experiments, the extinction of these conditioned stereotypies was studied in one series; in another series, the possible inhibition of conditioned stereotypies by the blocker of dopamine receptors, haloperidol, was measured. The rats were conditioned (or the controls pseudoconditioned, respectively) for either 3 or 10 days with 2.0 mg/kg s.c. apomorphine or 6 days with 0.5 mg/kg s.c. of the drug and by placing them into particular cages in the presence of an auditory and an olfactory stimulus. Under all these conditions, episodes of conditioned stereotypies were observed, when solvent + conditioned stimuli instead of apomorphine was applied 1 day after the last conditioning session (first session of extinction). The conditioned responses seemed to be on the highest level after conditioning with 2.0 mg/kg apomorphine 3 days, lower after conditioning with the same dose on 10 days, and even lower after conditioning for 6 days with 0.5 mg/kg. Under all these conditions, the stereotypies summed up and averaged for the total observation period of 60 min rapidly decreased during the extinction period, so that on day 4 of the extinction period, no further significant differences between conditioned and pseudoconditioned animals were observed, although a short initial period was still observed on the fourth day. On day 3 of extinction, not only an early, but also a late episode of conditioned stereotypies was manifest, interrupted by an almost silent period. The acute (unconditioned) stereotypies produced by 0.5 mg/kg s.c. apomorphine were almost completely suppressed by pretreatment with 0.1 mg/kg i.p. haloperidol. In contrast, the same dose of haloperidol produced a much less pronounced inhibition of conditioned stereotypies after conditioning with the same dose of apomorphine for 6 times. These results, together with previous findings, suggest that the conditioned behavioural effects are not due to an activation of dopaminergic mechanisms during conditioning with apomorphine.

Animals↗

Conditioned tolerance to haloperidol- and droperidol-induced catalepsy.

The possible mechanisms of conditioned tolerance to the cataleptogenic effects of haloperidol and droperidol were studied in order to discriminate between "classical" and "conditioned" tolerance. Rats were conditioned by repeated administration (19-27 times) of haloperidol (1.5 mg/kg i.p.) or droperidol (1.5 mg/kg i.p.), respectively, in the presence of a sum of defined environmental (auditory, olfactory and tactile) stimuli. The animals were compared with pseudoconditioned rats, which underwent the same number of drug injections and exposures to the environmental stimuli, but neither were associated. In part of the experiments, one further group of rats was repeatedly treated with only solvent in the presence of the environmental stimuli. Rats conditioned with haloperidol or droperidol showed tolerance to the cataleptogenic effect of a test dose of haloperidol (1.5 mg/kg i.p.) or droperidol (1.5 mg/kg i.p.), respectively, when they were tested in presence of the defined conditioning stimuli. The rats conditioned with droperidol showed significantly less catalepsy than the pseudoconditioned animals 30 min after droperidol administration, whereas in rats conditioned with haloperidol, the catalepsy was less pronounced no sooner than 120 min after haloperidol administration. This was a manifestation of conditioned tolerance. In rats pseudoconditioned with droperidol, the catalepsy was similar to that produced by the drug in drug-naive rats, suggesting no classical tolerance due to repeated administration of the neuroleptic drug. The dopamine turnover in striatum or nucleus accumbens after administration of 1.5 mg/kg of haloperidol i.p. was not altered in rats conditioned with haloperidol when compared with pseudoconditioned animals.(ABSTRACT TRUNCATED AT 250 WORDS)

3,4-Dihydroxyphenylacetic Acid↗

[Not Available].

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Contraception↗

[Fine-needle biopsy in the early diagnosis of thyroid neoplasms].

Among the patients directed to the Department of Endocrinology of the Institute of Internal Medicine for diagnostic examinations of the thyroid, 726 (647 women and 79 men, of age between 16 and 79 years) were qualified to surgery after scintigraphic detection of cold nodules. From this group, 474 patients had thin-needle biopsy specimens taken for cytologic examination. The results of the latter examinations have been compared with those of histologic examination performed on the tissue removed during surgery. The occurrence of a malignant tumor (in 99.1%--thyroid cancer) was found in 108 patients (22.8%) from the group having thin-needle biopsy performed. Comparison of the results of cytologic examination with those of postoperative histologic examination demonstrated low sensitivity of biopsy examination (50.0%), as opposed to high specificity (96.2%) and high accuracy (85, 3%). Analysis of the false-negative results (54/108) revealed that the main causes of errors are difficulties in differentiation of adenoma from follicular carcinoma. Widening of the indications to surgery by a group of patients with adenoma will increase sensitivity to 84.8% and will require including into the operated group of about 50% of patients with scintigraphically diagnosed cold nodules: The introduction of the new term: "urgent strumectomy", has been proposed; also a diagnostic algorithm, useful for early diagnosis of malignant tumors of the thyroid, has been discussed.

Adolescent↗

Alterations in regional energy metabolism in rat brain produced by small and by large doses of apomorphine: possible relations to autoreceptors.

Dose-dependent changes in behavioural patterns and in local cerebral glucose utilization (LCGU) following subcutaneous application of apomorphine were measured in conscious, unrestrained rats by means of a scoring system and of the autoradiographic [C14]2-deoxyglucose technique, respectively. The behavioural patterns of akinesia, ptosis, yawning and penile erections were scored. Akinesia and ptosis were most prominent after 0.02 and 0.07 mg/kg apomorphine but not after 0.18 mg/kg. Maximal scores for yawning and penile erections were obtained after 0.07 mg/kg. LCGU was not significantly changed after 0.07 mg/kg except for decreases in the cingulate cortex and hypothalamus. Apomorphine 0.5 mg/kg decreased LCGU in the cingulate, parietal and occipital cortex, anteromedial and lateral thalamus and lateral habenula but increased it in laminae IV and VI of the sensorimotor cortex, in the parafascicular nucleus of the thalamus, and in some parts of the basal ganglia and related nuclei. Similar changes in LCGU occurred after 2.0 mg/kg apomorphine, which also increased LCGU in the ventral tegmental area. The lower dose did not produce changes in LCGU opposite to those occurring after larger doses. The data obtained with LCGU do not support the idea that behavioural effects after low doses of apomorphine are elicited by activation of dopamine autoreceptors.

Animals↗

Studies on interactions between conditioned and unconditioned behavioural responses to apomorphine in rats.

Interactions between the direct (unconditioned) behavioural effects apomorphine and its conditioned effects after pairing with previously neutral stimuli were studied. Rats were injected once daily for 3-12 times, with apomorphine (2.0 mg/kg or 0.5 mg/kg or 0.07 mg/kg s.c. the dose kept constant in each series), in the presence of defined environmental stimuli (a wire cage in association with an acoustic and an olfactory stimulus) as conditional stimuli. The two larger doses produced stereotyped sniffing, licking, and gnawing, the smallest dose akinesia, ptosis, yawning and penile erections. During the conditioning phase, the drug produced most of the effects with increasing intensity and in the case of the stereotypies, there also was a shift to higher scores of stereotypy, with a reduced latency in onset of the signs. On the test day, 1 day after the last administration of apomorphine, the conditioned rats as well as "pseudoconditioned" controls were treated with a test dose of apomorphine in the presence of the conditional stimuli. Pseudoconditioned rats had been treated with the same pharmacological schedule of apomorphine and had the same familiarity with the stimuli, but both were kept separate. A test dose of 0.5 mg/kg of apomorphine produced stereotypies with a significantly higher score and shorter latency in onset in conditioned than in pseudoconditioned rats. Rats conditioned with the lowest dose showed a significantly longer total duration and a shorter latency in onset of akinesia and ptosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Conditioning of behavioural effects produced by an intermediate dose of apomorphine: hypokinesia, ptosis and stereotypies.

Apomorphine, in an intermediate dose (0.18 mg/kg s.c.) decreased dopamine turnover and produced signs generally attributed to a decrease in dopaminergic neurotransmission, e.g. ptosis and yawning, as well as signs of an increased stimulation of dopamine receptors in dopaminoceptive target neurones, e.g. stereotyped sniffing. In contrast, the former signs were exclusively observed after smaller doses and the latter after larger doses of apomorphine. Since it had been shown in previous studies that these signs, except yawning, could be conditioned in association with discriminative stimuli in the environment, the present study using conditioning experiments with this intermediate dose aimed at determining, 1. the time course of each conditioned response, 2. the interaction of conditioned and unconditioned responses, and 3. the conditions under which hypokinesia occurred. In each series, conditioned animals were compared with pseudoconditioned controls. Rats were conditioned for 8 days with apomorphine, and on day 9, treated with saline in presence of the conditional stimuli (a test cage in combination with acoustic and olfactory stimuli). In contrast to pseudoconditioned controls, ptosis and stereotyped behaviour were observed in conditioned rats, sometimes occurring alternatingly. These signs closely resembled the direct, unconditioned pharmacological effects. In addition, akinesia occurred after conditioning, although it was never manifest as a pure drug response, nor during the conditioning period. In contrast, yawning was observed in pseudoconditioned as well as in conditioned rats, although slightly more frequently in the former animals. Subsequently, the rats were again conditioned (or pseudoconditioned) on days 10-14 with apomorphine and both groups tested with the same dose (0.18 mg/kg) of apomorphine in the presence of the conditioned stimuli.(ABSTRACT TRUNCATED AT 250 WORDS)

3,4-Dihydroxyphenylacetic Acid↗

Conditioning of behavioural signs produced by nomifensine and by B-HT 920 in rats.

Conditioning of behavioural effects produced by two drugs acting differently upon dopaminergic neurotransmission was studied. Nomifensine and the putative dopamine autoreceptor agonist B-HT 920 produce contrasting effects on motility, namely increases in locomotor activity and stereotypies as compared to hypokinesia and ptosis. The administration of each of these drugs (US) was repeatedly associated with well-defined environmental stimuli (CS): a wire cage associated with an auditory and on olfactory stimulus. The rats were conditioned for 7 days with 20 mg/kg nomifensine IP each day. After conditioning, the rats were treated with the solvent alone in presence of the CS. Not only did sniffing and licking occur, but also gnawing, even though the latter response was not evident after acute administration of the drug or during the conditioning period. Nomifensine (20 mg/kg IP) also acutely decreased the ratio of 3,4-dihydroxyphenylacetic acid/dopamine concentrations (DOPAC/DOPAMINE); this ratio was not altered in the conditioned rats, 60 min after solvent administration in presence of the CS. Rats were conditioned with 0.02 mg/kg IP B-HT 920 daily for 8 days. During the conditioning phase, akinesia and ptosis showed a slight enhancement and a faster onset. After conditioning, when the rats were treated with the solvent alone, the majority of them showed akinesia and/or ptosis during the observation period, in contrast to pseudoconditioned controls. When these rats were conditioned or pseudoconditioned, respectively, with B-HT 920 for further 5 days using 0.02 mg/kg again, treatment with the same dose in presence of the CS produced a significant enhancement and acceleration of these signs in conditioned as compared with pseudo-conditioned control rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Conditioning of pre- and post-synaptic behavioural responses to the dopamine receptor agonist apomorphine in rats.

We investigated whether pharmacological effects of the dopamine agonist apomorphine can be conditioned by establishing an association of apomorphine administration with exteroceptive cues. Apomorphine was repeatedly administered and subsequently, the rat was put into a test cage and exposed to an acoustic and an olfactory stimulus ("conditioned rats"). Control animals ("pseudoconditioned" rats) were treated with the same pharmacological schedule of apomorphine not temporally associated with the stimuli. On the test day, both groups were injected with saline and exposed to the stimuli described. The stereotyped behaviour produced by large doses of apomorphine (0.5 or 2.0 mg/kg SC), namely sniffing, licking and gnawing, could be conditioned in a pronounced way. During the conditioning period, a change in the stereotypies was observed with regard to the time-course (earlier occurrence) and to the character of the stereotypies (from sniffing to licking and gnawing), when 0.5 mg/kg apomorphine was used, but not with the dose of 2.0 mg/kg. The conditioned responses showed a relatively uniform distribution during the observation period with some increase towards the end of the observation period. Some signs produced by a low dose of apomorphine (0.07 mg/kg SC), namely hypomotility and ptosis, but not yawning, could also be conditioned, although in a less pronounced way. An intermediate dose of apomorphine (0.18 mg/kg SC) produced both signs observed after large doses and those observed after a small dose, occurring alternatingly. Both types of signs could be conditioned using this dosage. Conditioning did not alter striatal or mesolimbic dopamine turnover.(ABSTRACT TRUNCATED AT 250 WORDS)

3,4-Dihydroxyphenylacetic Acid↗