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A Dabrowski

Publications and source records attributed to A Dabrowski.

At least 73 records · Page 4Linked to original sources
PubMed1996

Stress-activated protein kinase activation is the earliest direct correlate to the induction of secretagogue-induced pancreatitis in rats.

We compared the cellular events induced by hyperstimulation of rats with caerulein which induces acute pancreatitis, to bombesin, which does not induce pancreatitis. Both secretogogues induced the intracellular activation of trypsinogen and the colocalization of lysosomal hydrolases and zymogen granules within 10-15 minutes. These data indicate that these parameters, previously thought to be crucial initiating events of pancreatitis, are not definitive cellular markers of the disease. We then compared the abilities of the two secretagogues to activate stress-activated protein kinase (SAPK). Significant effects of caerulein hyperstimulation on SAPK activity were observed within 5 minutes, the maximum (57-fold) activation was evident after 15 minutes, and levels remained above control for at least 3 hours. In comparison, hyperstimulation with bombesin induced a maximal 5-fold increase of SAPK activity which returned to basal within one hour. These data indicate that SAPK activity is the earliest and best correlated cellular marker associated with secretagogue-induced pancreatitis.

Animals↗
PubMed1996

Jun kinases are rapidly activated by cholecystokinin in rat pancreas both in vitro and in vivo.

Stimulation of pancreatic acini from male Sprague-Dawley rats by both cholecystokinin (CCK)-8 and anisomycin caused an increase in p46jnk and p55jnk activities. Both forms of c-Jun amino-terminal kinase (JNK) were slightly activated at 5 min, reached a maximum at 30 min, and remained significantly increased at 60 min of CCK stimulation. By contrast, p42mapkwas activated fully by 5 min. In pancreatic acini stimulated with different concentrations of CCK for 30 min, the minimal and maximal JNK responses were observed at 30 pm and 100 nM CCK, respectively; p42mapk activation was, as previously reported, much more sensitive, with maximal activation by 1 nm CCK. Carbachol and bombesin also stimulated JNK activity, while vasoactive intestinal peptide did not. Neither activating protein kinase C nor increasing intracellular Ca2+ significantly activated JNK. In in vivo experiments, rats were infused intravenously for 5 and 15 min with a secretory (0.1 microg/kg/h) or supramaximal (10 microg/kg/h) dose of the CCK analog caerulein (CER). Secretory doses of CER induced a 4-fold increase of both forms of JNK in pancreatic tissue at 5 and 15 min, while at the same time points, supramaximal stimulation with CER caused 4- and 27-fold increases, respectively, of these kinase activities. The secretory dose of CER slightly increased the activities of both forms of mitogen-activated protein kinase, while the supramaximal dose induced a 10-fold increase of p42mapk at 5 min. In conclusion, JNKs and mitogen-activated protein kinases are rapidly activated in rat pancreatic acini stimulated with CCK as well as in pancreatic tissue during in vivo stimulation with CER. The large response to supramaximal CER stimulation may be of importance in the early pathogenesis of acute pancreatitis.

Animals↗
PubMed1996

Ventricular tachycardia rate variability as a new predictor of sudden death in patients with remote myocardial infarction.

BACKGROUND: Clinical data have shown that evaluation of sinus rhythm variability is a useful test for selection of high-risk patients after myocardial infarction. The purpose of this study was to test the hypothesis that measures of ventricular rate variability (VRV) during non-sustained ventricular tachycardia (NSVT) may be helpful in predicting sudden death in patients with a remote myocardial infarction. METHODS: The study group comprised 162 patients with remote myocardial infarction who showed NSVT on 24 h ECG recording. Temporal changes in up to 10 beat-to-beat V-V intervals of NSVT episodes were assessed. The following parameters of VRV-NSVT were calculated: average value of successive differences in V-V intervals (ADVV); normalized average value of successive differences in V-V intervals (nADVV). RESULTS: During a mean follow-up of 4 years, 57 patients (35%) had died; sudden death was identified in 34 (21%). Patients who died suddenly had significantly (P < 0.001) lower values of ADVV and nADVV variables compared with survivors or those whose death was not sudden. The incidence of sudden death was assessed in the group of patients with more stable cycle durations in the episodes of NSVT (expected to be at high risk) and in the group with more variable cycle durations (expected to be at low risk). The relative risk of sudden death for patients with ADVV values less than 30 ms was 3.2 compared with those with ADVV values of at least 30 ms (P < 0.001), and that for patients with nADVV values less than 6% was 3.0 compared with those with nADVV values of at least 6% (P < 0.001). CONCLUSIONS: These results indicate a relationship between regularity of NSVT rhythm and risk of sudden death. The assessment of VRV-NSVT can be used to identify patients with NSVT who remain at high risk after myocardial infarction.

Aged↗
PubMed1996

Heart rate variability before sudden blood pressure elevations or complex cardiac arrhythmias in phaeochromocytoma.

In phaeochromocytoma, sudden hypertensive or arrhythmic episodes are believed to be associated with excessive free catecholamine excretion. However, lack of correlation between blood pressure (BP) and plasma catecholamine levels has been reported. Therefore an attempt was made to assess the sympathovagal balance before and during episodes of BP elevation or complex cardiac arrhythmias in this disease. Ten patients with phaeochromocytoma and 10 matched controls with essential hypertension underwent simultaneous 24 h Holter ECG and BP monitoring. BP elevation was diagnosed when the BP exceeded the mean 24 h values by 40 mm Hg systolic or 30 mm Hg diastolic, respectively. Heart rate variability (HRV) was measured for 5 min periods 1 h before, 15 min before and during 13 episodes of BP elevation in phaeochromocytoma and 13 episodes in the control group, as well as at 1 h, 15 min and immediately before five arrhythmic events in phaeochromocytoma. In phaeochromocytoma, vagal activity measured 1 h before BP elevation was markedly higher than in control hypertensives. However, in both groups at 15 min before and during the hypertensive events, the vagal tone decreased significantly. In contrast, just before the arrhythmic events HRV remained unaltered with a slight insignificant increase in sympathetic activity. We conclude that in phaeochromocytoma, pronounced BP elevations during daily activities are preceded by a parasympathetic withdrawal, similar to the findings in essential hypertension. Such a sequence does not seem to precede sudden complex arrhythmic events in phaeochromocytoma.

Adrenal Gland Neoplasms↗
PubMed1996

[Pseudomyxoma peritonei secondary to a teratoma of the omentum with a mucinous component of borderline malignancy].

A mature cystic teratoma of the omentum occurred in a 37 years old woman who had an appendicectomy at the age of 8. This extragonadal teratoma contained a predominant mucinous glandular pattern of borderline malignancy, responsible for pseudomyxoma peritonei. Ovarian biopsies had only shown surface mucinous deposits at the time of the first laparotomy but two years later ovarian mucinous cystadenomas of borderline malignancy appeared. The patient developed intestinal obstruction, surround by mucinous retractile material and died four years and an half after initial diagnosis. This case is, to our knowledge, the first pseudomyxoma peritonei occurring from an extragonadal teratoma, the events chronology suggesting the secondary nature of the ovarian tumors.

Adult↗
PubMed1996

[Pseudoaneurysm of the pancreas].

A case pancreas pseudoaneurysm in chronic pancreatitis in 41-years old man is described. A big (12 cm) cyst with rotating fluid inside has been determined in USG examination. The patient has been operated on. The injury of the hepatic communis artery was the source of bleeding into the cyst. The artery has been ligated and the Jurasz operation has been performed. Post-operative course uncomplicated.

Adult↗
PubMed1995

Heart rate variability in pheochromocytoma.

The results of our study show that parasympathetic tone was higher in patients with pheochromocytoma than in patients with primary hypertension. An unusual spectral form of vagal activity was seen during excessive beta-adrenergic stimulation, while persistent hypertension with an excessive alpha-adrenergic stimulation was responsible for low cardiac sympathetic tone, probably due to desensitization of beta-adrenergic receptors.

Adrenal Gland Neoplasms↗
PubMed1995

The effect of platelet activating factor antagonist (BN 52021) on acute experimental pancreatitis with reference to multiorgan oxidative stress.

Acute hemorrhagic pancreatitis was induced in Wistar rats using a retrograde intraductal injection of 5% Na-taurocholate. Rats were treated with platelet-activating factor receptor (PAF) antagonist--BN 52021 (5 mg/kg) and sacrificed at 1 and 3 h after induction of acute pancreatitis. Malondialdehyde and sulfhydryl groups concentration were measured in pancreatic, lung, and liver tissue as a parameter of oxidant-antioxidant balance. We have shown that BN 52021 exerts only partial protecting effect against Na-TC-induced AP in rats. The positive effects of BN 52021 were expressed by: (1) Significant reduction of hyperamylasemia accompanied by lower malondialdehyde accumulation in pancreatic tissue; (2) Prevention of sulflhydryl groups depletion in lung tissue; (3) Diminution of necrotic and inflammatory changes in pancreatic tissue; and (4) Improvement of survival rate. We suggest that these effects may depend on the inhibition of PAF-mediated activation and oxidant generation by phagocytes.

Acute Disease↗
PubMed1995

[Uterine hemangiopericytomas. Two case reports].

The diagnosis of uterine haemangiopericytoma is still a matter of debate. The existence of haemangiopericytoma must be proven on the basis of classical histology, ultrastructure histology and immunohistochemical analyses. The diagnosis, even when apparently sure, must nevertheless be proven. We described two cases emphasizing the clinical and laboratory features of uterine haemangiopericytoma. Progress in nuclear magnetic resonance imaging, ultrastructural analysis and immunohistochemistry should help in confirming the diagnosis of haemangiopericytoma. Highly vascular leiomyoma or low malignity grade leiomyosarcoma have been mistakenly identified as haemangiopericytoma.

Adult↗
PubMed1995

Influence of alpha-adrenergic blockade on ventricular arrhythmias, QTc interval and heart rate variability in phaeochromocytoma.

There are strong experimental evidences that alpha 1-adrenergic stimulation significantly influences cardiac arrhythmogenesis, especially during myocardial ischaemia and reperfusion. However, anti-arrhythmic effects of alpha-blockade in humans were scarcely utilised. Thus the purpose of our study was to assess these effects in patients with phaeochromocytoma. In 22 patients simultaneous 24 h ECG and blood pressure (BP) monitoring, as well as estimation of the urinary 24 h free catecholamine excretion, were performed twice: before and during the treatment with the non-selective alpha-blocker, phenoxybenzamine. The heart rate variability was measured during four 5 min periods, at 10.00, 16.00, 22.00 and 04.00. During alpha-blockade systolic blood pressure (SBP) decreased from 137.6 +/- 23.8 to 126.5 +/- 15.7 mm Hg (P < 0.01), heart rate increased from 83.0 +/- 9.9 to 88.5 +/- 10.0/min (P < 0.02) and duration of QTc interval unsignificantly increased. Incidence of frequent or repetitive ventricular arrhythmias was significantly higher before treatment (in 9 vs 3 of 22 patients, P < 0.05). Heart rate variability significantly decreased during the treatment, with regard to all parameters, representing both the sympathetic and parasympathetic activity. We conclude that non-selective alpha-blockade significantly decreases the incidence of frequent or repetitive ventricular arrhythmias in patients with phaeochromocytoma, although the lack of QTc interval shortening suggests that the effect of class I drugs may participate in the anti-arrhythmic effects of phenoxybenzamine. Moreover, non-selective alpha-blockade in phaeochromocytoma significantly diminishes vagal activity.

Adrenal Gland Neoplasms↗
PubMed1994

Nitric oxide contributes to multiorgan oxidative stress in acute experimental pancreatitis.

BACKGROUND: Nitric oxide is a highly reactive free radical gas. The study was undertaken to determine the nitric oxide contribution to oxidative stress in acute experimental pancreatitis induced in Wistar rats. METHODS: Acute haemorrhagic pancreatitis was induced in male Wistar rats by means of a retrograde intraductal injection of 5% Na-taurocholate. The rats were treated with the nitric oxide donor, sodium nitroprusside (SNP) (0.25 mg/kg), or with N omega-nitro-L-arginine methyl ester (L-NAME) (10 mg/kg), which is an inhibitor of nitric oxide synthase. We measured malondialdehyde and sulphhydryl group concentrations in pancreatic, lung, and liver tissue. RESULTS: In rats with acute pancreatitis treated with SNP, oxidative stress, expressed by malondialdehyde increase and sulphhydryl group depletion, was much more pronounced than in the other groups. In contrast, intensity of the oxidative stress was significantly reduced in rats treated with L-NAME. CONCLUSION: The data suggest that nitric oxide is partly responsible for oxidative stress in acute haemorrhagic pancreatitis.

Acute Disease↗
PubMed1994

[Efficacy of slow-release betamethasone in Churg-Strauss syndrome. Apropos of a case].

A case of Churg-Strauss syndrome was observed in a young woman with asthma and an elevated eosinophil count. The lungs, skin, joints, stomach and heart were involved. The diagnosis was established on the basis of the clinical picture and results of the surgical lung biopsy. Outcome has been favourable for 6 years with a chronic treatment with dipropionate and slow-release betamethazone phosphorane which has the same effectiveness as cyclophosphamide and prednisone. Clinical improvement was observed during pregnancy and lactation.

Adult↗
PubMed1994

The effect of nafamostat mesilate (FUT-175) and gabexate mesilate (FOY) on multiorgan oxidant-antioxidant balance in acute experimental pancreatitis.

This study was undertaken to determine whether synthetic proteinase inhibitors--nafamostat mesilate (FUT-175) and gabexate mesilate (FOY) have any influence on multiorgan oxidant-antioxidant balance in acute haemorrhagic pancreatitis induced in Wistar rats using a retrograde intraductal injection of 5% Na-taurocholate. Rats were treated with FUT-175 25 x 10(-3) g.kg-1.h-1) or FOY (2.5 x 10(-3) g.kg-1.h-1) and sacrificed at 3 h. Malondialdehyde and sulfhydryl groups concentration, as an index of oxidative stress, we measured in pancreatic, lung and liver tissue. In rats with acute pancreatitis treated with these proteinase inhibitors, oxidative stress expressed by malondialdehyde elevation and sulfhydryl groups depletion, was markedly diminished. It was observed in the pancreas and lung, and to a lesser extent in the liver. These effects of FUT-175 or FOY treatment, at least in part, may account for recently postulated favorable systemic effects of such a medication.

Acute Disease↗
PubMed1993

[Unexplained syncope. Likelihood of inducing sustained ventricular tachycardia with electrophysiologic examination].

In patients with unexplained syncope and documented nonsustained VT or complex premature ventricular beats indication for programmed ventricular stimulation (PVS) should be considered. However, the variables derived from noninvasive methods that predict diagnostic yield of PVS are incompletely defined. The purpose of this study was to elucidate the role of noninvasive testing variables in predicting inducible monomorphic sustained ventricular tachycardia (SVT) in 116 patients (pts) presenting with syncope. The study group consisted of 45 pts with remote Q wave myocardial infarction. 5 pts with non-Q wave myocardial infarction, 21 pts with another heart disease and 45 pts without organic heart disease. All pts underwent standard ECG, Holter monitoring, echocardiography, signal-averaged ECG and PVS with 1, 2 and 3 extrastimuli at three basic cycle lengths. Nonsustained VT, low ejection fraction, prolongation of QTc interval, abnormal Q waves in postinfarction pts (Q-MI) and late potentials (LP) indicate a greatly increased probability of inducible SVT. Inducible SVT was present in 15 of 45 (33%) pts with Q-MI. Although in the group of 71 pts without Q-MI, nonsustained VT on Holter monitoring was detected in 20 pts, LP in 16 pts, prolongation of QTc interval in 3 pts and low ejection fraction in 2 pts, the positive yield of PVS was documented in only one case (1%). The combination of Q-MI and LP best predicted inducible SVT showing a sensitivity of 75%, specificity of 93%, overall predictive accuracy of 91%, predictive value of positive response of 63% and negative response of 69% to identify pts who would have inducible SVT. Thus, the combination of Q-MI and LP variables was shown as the best predictor of inducible SVT in pts with unexplained syncope. In pts without Q-MI the noninvasive testing variables have considerably less value in selection of pts to PVS, because inducible SVT is very rare in this population.

Adult↗
PubMed1993

[Paroxysmal loss of consciousness. Comparison of electrophysiologic and holter monitoring results].

Holter monitoring is one of the most commonly done test in the evaluation of patients with syncope. As Holter monitoring may miss an arrhythmia or document an asymptomatic arrhythmia invasive electrophysiologic testing has been applied in patients with syncope. The purpose of this study was to compare Holter monitoring and electrophysiologic tests in patients with syncope of unexplained origin. The group consisted of 100 patients with syncope of unknown origin. Coronary artery disease was present in 43 patients, other heart disease in 19 patients and no structural heart disease was found in 38 patients. Electrophysiological testing consisted of (1) recording of His bundle electrogram, (2) atrial stimulation, (3) ventricular stimulation with 1.2 and 3 extrastimuli at three basic cycle lengths. The results of Holter monitoring were classified by severity of abnormalities into three classes: I--normal study; II--moderate abnormalities; III--severe abnormalities: sinus rhythm with pauses longer than 3 s, Mobitz II or complete atrio-ventricular block, supraventricular arrhythmia faster than 180 bpm, sustained ventricular tachycardia. Abnormalities of electrophysiologic testing were grouped as: I normal study; II--moderate abnormalities; III--severe abnormalities: sinus nodal recovery time more than 3 s, HV interval longer than 100 ms, supraventricular arrhythmia faster than 200 bpm, sustained ventricular tachycardia. Class III abnormalities were documented in 17 patients on Holter monitoring and in 20 patients by electrophysiologic testing. Compatibility between class III abnormalities in Holter monitoring and electrophysiological testing was noted in 4 patients, discordance of class III results in 33 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Inflammatory pseudotumor of the urachus. A case].

The occurrence in a 9-year old boy of a painful, prominent and solid mid-hypogastric tumour is reported. This clinically isolated muscular tumour was suggestive of sarcoma. En bloc resection of the tumour including the attached vesical cupula was performed. Histology showed that this large tumour was purely inflammatory and had developed from remnants of the urachus. This diagnosis must be considered whenever a suprapubic tumour is discovered. Since malignant transformation of urachus cysts is possible, surgical resection is advised.

Child↗