Pentadecapeptide BPC 157, Cimetidine, Ranitidine, Bromocriptine, and Atropine Effect in Cysteamine Lesions in Totally Gastrectromized Rats (A Model for Cytoprotective Studies)

A superior effectiveness in various lesionassays was noted for the novel pentadecapeptide BPC 157,originated from human gastric juice protein (BPC) andclaimed to be a cytoprotective agent. From this viewpoint, as a previously untreatedexperimental improvement to create an acid-freeenvironmental for cytoprotection studies, totalgastrectomy was done 24 hr before the ulcerogenicprocedure. In the absence of stomach and gastric acid, the damagingeffects of cysteamine (400 mg/kg subcutaneously, death24 hr thereafter), to date thought to be an acid-relatedduodenal ulcerogen, and the BPC 157 cytoprotective effect (10 mug or 10 ng/kg intraperitoneally)were further challenged. BPC 157 was compared withreference agents [cimetidine (50), ranitidine (10),omeprazole (10), bromocriptine (10) and atropine (10) (mg/kg intraperitoneally, 1 hr beforecysteamine] known to be also cytoprotective. In naiverats, with intact stomach, all of them showed a strongbeneficial effect. Interestingly, in gastrectomizedanimals, the application of BPC 157 or the referenceagents before cysteamine significantly prevented theotherwise severe duodenal lesion development noted inthe control gastrectomized cysteamine rats. In groups without cysteamine, no lesions were noted(laparotomy, gastrectomy only, 24 or 48 hr postsurgicalperiod), nor was lesion potentiation seen incysteamine-treated laparotomized animals. In summary,these findings -- equal damaging effect ofcysteamine and equal protection of pentadecapeptide BPC157 and reference agents in gastrectomized and rats withintact stomach -- seem to be particularly relevantfor a cytoprotective viewpoint. Without a stomach,the cysteamine damaging effect was convincingly definedas an essential gastric acid-independent injury(analogous to ethanol gastric lesions). Likewise, a high cytoprotective capacity,apparently acid independent, common for all testedagents (novel pentadecapeptide BPC 157, cimetidine,ranitidine, omeprazole and atropine) could be clearlystressed.     

The ability of heat stress and metabolic preconditioning to protect primary rat cardiac myocytes

Primary rat cardiocytes were subjected to either thermal preconditioning for 30 min at 43°C or 20 min metabolic preconditioning (10 mM deoxyglucose, 20 mM lactate, pH 6.5). Eighteen hours later cells were analysed either for hsp 70i expression or subjected to a subsequent lethal heat stress or simulated ischaemia (10 mM deoxyglucose, 20 mM lactate, 0.75 mM sodium dithionite, 12 mM potassium chloride, pH 6.5) for 2 hours and assessed for survival by trypan blue exclusion.Hsp 70i was induced over 100 fold by thermal preconditioning and 30 fold by metabolic preconditioning (p<0.001, p<0.05), hsp 90 was induced 2.71 fold and 2.24 fold (p<0.001, p<0.001) by thermal and metabolic preconditioning respectively, while hsp 60 was not induced by either treatment. Preconditioned cultures had improved survival against subsequent lethal heat stress or simulated ischaemia: Thermal preconditioning reduced death from 69.22% to 52.46% upon subsequent lethal heat stress and from 49.13% to 36.66% upon subsequent lethal simulated ischaemia. Metabolic preconditioning reduced cell death from 51.29% to 33.8% against subsequent lethal heat stress, and from 69.09% to 55.61% upon subsequent lethal simulated ischaemia. A second marker of cell death, the release of lactate dehydrogenase activity into the culture media, was reduced to 65% and 60% of control values for thermally preconditioned cells subjected to lethal heat or lethal simulated ischaemia respectively. Metabolically preconditioned cells demonstrated lactate dehydrogenase activity of 59% and 51% that of control values, when subjected to lethal heat or lethal simulated ischaemia respectively.Abbreviations hsp heat stress protein - hsp 70i inducible 70 kDa heat stress protein - LDH lactate dehydrogenase - PBS phosphate buffered saline     

Lavage Administration of Dilute Surfactant in a Piglet Model of Meconium Aspiration

Maldistribution of exogenous surfactant may preclude any clinical response in acute lung injury associated with surfactant dysfunction. Our previous studies have shown the effectiveness of surfactant lavage after homogenous lung injury. The present study utilizes a histologically confirmed non-homogeneous lung injury model induced by saline lung-lavage followed by meconium injected into a mainstem bronchus. Piglets were then treated with Infasurf® or Exosurf® by lavage (I-LAVAGE, n=7; E-LAVAGE, n=5) or bolus (I-BOLUS, n=8; E-BOLUS, n=5), or went untreated (CONTROL, n=4). Lavage administration utilized a dilute surfactant (35 ml/kg; 4 mg phospholipid/ml) instilled into the lung, followed by gravity drainage. The retained doses of the respective surfactant in the lavage and bolus groups were similar. Results showed that the surfactant distribution was more uniform in the lavage groups compared to the bolus groups. Significant and consistent increases in PaO₂ were observed in the lavage groups compared to the bolus groups and the controls. PaO₂ (mmHg) at 240 min posttreatment: I-LAVAGE=297±54, E-LAVAGE= 280±57; I-BOLUS=139±31; E-BOLUS=152±29; C=119±73 (mean± SEM). Other improved pulmonary function parameters favored lavage administration. We conclude that better surfactant distribution achieved by lavage administration can be more effective than bolus administration in this type of non-homogeneous lung injury.     

Mechanisms of transforming growth factor-alpha (TGF-alpha) induced gastroprotection against ethanol in the rat: roles of sensory neurons,sensory neuropeptides,and prostaglandins

The mechanisms by which transforming growth factor- (TGF-) protects the stomach against mucosal injury are incompletely understood. The aim of this study was to examine the roles of sensory neurons, sensory neuropeptides and prostaglandins in TGF gastroprotection against ethanol. Fasted rats received TGF- (50 g/kg, intraperitoneally) prior to orogastric ethanol (75% v/v, 1 ml). Gastric injury was quantitated 30 min after ethanol. Involvement of sensory neurons and the sensory neuropeptides, calcitonin gene-related peptide (CGRP) and substance P (SP), were examined by capsaicin deafferentation and specific receptor antagonist infusion, respectively. Indomethacin (10 mg, intragastrically) was used to determine the role of prostaglandins in TGF--mediated gastroprotection. TGF- significantly diminished ethanol-induced gastric lesion area to 5.7 ± 0.8 mm² vs 4l.1 ± 5.2 mm² (P < 0.001). Sensory denervation and CGRP-receptor blockade abolished the TGF- protective effect. In contrast, SP antagonist and indomethacin did not alter TGF- gastroprotection. In conclusion, TGF--mediated gastroprotection involves sensory neuron activation and CGRP release and this protective effect did not involve substance P or prostaglandin generation.     

Prognostic significance of the heterogenous expression of IgG Fc receptors in B-cell chronic lymphocytic leukemia

Summary Receptors for the Fc part of IgG (FcR) are expressed in three forms on peripheral blood lymphocytes. The presence of the releasable form (FcR_REL.) as well as of the two nonreleasable forms with lower (FcR_LOW) and higher (FcR_HIGH) cellular avidity was correlated with survival in 63 patients with B-cell chronic lymphocytic leukemia (B-CLL). High percentage of cells with FcR_LOW as well as high absolute number of cells carrying the two nonreleasable forms of FcR were connected to unfavorable prognosis. Combining these three parameters, an FcR constellation was defined which pointed to a favorable prognosis (in 24 patients) when all three parameters were low, but detected short survivors when all three data were high (in 14 patients). The FcR constellation was capable of identifying patients with better or worse prognosis within groups that were homogeneous regarding some other known prognostic factors. FcR constellation as a prognostic factor was shown to be independent of age, sex, and Rai and Binet stages, but it was found to be connected with the total tumor mass score (TTM). The three forms of FcR on B cells might reflect stages of B-cell activation. Differences in FcR constellations between patients with B-CLL would thus correspond to differently activated B-cell clones with variable prognosis.     

Serum cytokines in patients with rheumatoid arthritis

Serum cytokines such as interleukin 1 (IL-1), interferon (IFN-), and tumor necrosis factor (TNF) were measured in 40 patients with rheumatoid arthritis (RA). In the 40 patients studied, serum IL-1 was detected in 5 patients, IFN- in 10 patients, and TNF in 20 patients. The IL-1-positive group showed increased values of activity indices compared to the IL-1-negative group. Values of serum IFN- correlated well with the number of peripheral blood lymphocytes and CD3⁺ cells and with the percentage of CD3⁺ CD26⁺ cells. Values of serum TNF correlated positively with the number of peripheral blood monocytes and the percentage of CD3⁺ HLA-DR⁺ and CD3⁺ CD25⁺ cells. These results indicated that serum IL-1 in RA patients reflects the activity of RA, while the serum IFN- and TNF in RA patients may be related to circulating activated lymphocytes and monocytes, respectively.     

B cell adrenoceptors and sulphonylurea-induced insulin release in mouse islets

Summary Interactions of tolbutamide and glibenclamide with B cell adrenoceptors have been reported. This study evaluated the possible role of such interactions in the stimulation of insulin release. Mouse islets were incubated in the presence of 10 mmol/l glucose alone or with tolbutamide (10 mol/l) or glibenclamide (0.02 mol/l). At 0.01–10 mol/l, blockers of ₂-adrenoceptors (yohimbine, idazoxan) or ₁-adrenoceptors (prazosin) had practically no effect on glucose-induced insulin release and did not affect its potentiation by sulphonylureas, except for a slight increase by 10 mol/l prazosin and idazoxan. Nonspecific -blockers (phentolamine, dihydroergotamine) increased control release at 10 mol/l, but only the latter amplified the response to tolbutamide. Blockers of -adrenoceptors were tested at 0.1–100 mol/l: propranolol (₁, ₂), metoprolol (₁) and compound ICI 118-551 (₂). They increased glucose-induced insulin release at 100 mol/l but variably altered the effect of sulphonylureas. Blockers of adrenoceptors have, thus, no effect on insulin release in vitro at therapeutic concentrations. At high concentrations, they non-specifically affect the action of sulphonylureas. We conclude that an interaction with B cell adrenoceptors is not involved in the insulinotropic action of sulphonylureas.     

Heat shock protein induction in rat pancreatic islets by recombinant human interleukin 1β

Summary Interleukin 1, potentiated by tumour necrosis factor , is cytotoxic to pancreatic Beta cells in vitro. We have hypothesized that interleukin 1 induces oxygen free radicals in Beta cells. Since cytotoxicity induced by free radicals and by heat may activate the same cellular repair mechanism (the heat shock response), the aim of this study was to investigate the pattern of protein synthesis in isolated islets after exposure to interleukin 1 (150 pg/ml, 24 h), tumour necrosis factor (50 ng/ml, 24 h), heat shock (43°C, 30 min) and H₂O₂ (0.1 mmol/l, 20 min). By polyacrylamide gel electrophoresis, autoradiography, Western-blot analysis and partial peptide mapping of ³⁵S-methionine labelled islets, interleukin 1 was found to induce a 73 kilodalton protein belonging to the heat shock protein family heat shock protein 70, a heat shock protein 90, and haem oxygenase. A minor induction of heat shock protein 73 and haem oxygenase was seen after H₂O₂. Interleukin 1 did not induce heat shock proteins in rat thyroid cells, rat mesangial cells or in human monocytes. Tumour necrosis factor did not induce selective protein synthesis. Pre-exposure of islets to heat, tumour necrosis factor , or H₂O₂ did not prevent the impairment of glucose-stimulated insulin release seen after 24 h of interleukin 1 exposure. The data are compatible with free radical induction by interleukin 1. However, the heat shock response is not specific for oxidative injury, and previous studies have shown discrepant effects as to a protective effect of free radical scavengers against interleukin 1-mediated beta-cytotoxicity. Thus, a role for free radicals in this context is not definitely proven.     

Role of histamine H3 receptors in control of mouse intestinal motility in vivo and in vitro: comparison with alpha2-adrenoceptors

We tested drugs acting at histamine H₃ receptors in mice on the gastrointestinal transit of a charcoal meal in vivo and on neurogenic contractions of isolated ileal preparations. The agonist (R)--methylhistamine (100 mol/kg) caused a maximum 25% reduction of gastrointestinal transit, an effect mimicked by immepip (100 mol/kg) and antagonized by thioperamide (20 mol/kg) or clobenpropit (20 mol/kg). In the isolated ileum, (R)--methylhistamine (10–100 M) caused a slight, thioperamide-insensitive, reduction (maximum 15%) of electrically evoked cholinergic contractions. In comparison, the ₂-adrenoceptor agonist clonidine (0.1 mol/kg) caused a 35.2% inhibition of the gastrointestinal transit and almost completely reduced (maximum 82% at 1 M) the cholinergic contraction of the isolated ileum, both effects being antagonized by idazoxan (0.4 mol/kg and 1 M, respectively). These results suggest that histamine H₃ receptors, located outside the myenteric plexus, mediate an inhibition of the gastrointestinal transit in vivo. Conversely, the presence of ₂-adrenoceptors in the cholinergic nerve endings and their inhibitory role in the control of gastrointestinal propulsion is confirmed.     

Use of cultured human tissues and cells in carcinogenesis research

Summary A variety of approaches are used to study carcinogenesis. Recent advances in techniques for culture of human tissues and cells have provided additional experimental systems of study the process of carcinogenesis and the genetics of cancer.The Journal of Cancer Research and Clinical Oncology publishes in loose succession Editorials and Guest Editorials on current and/or controversial problems in experimental and clinical oncology. These contributions represent exclusively the personal opinion of the author.     

Correlation between infarct-related coronary artery patency and predischarge electrocardiographic patterns in patients with first anterior myocardial infarction who received thrombolytic therapy

The aim of this study was to investigate the correlation between the ST-segment and T-wave patterns in predischarge electrocardiogram and patency of left anterior descending coronary artery in patients with a first anterior myocardial infarction (AMI). One hundred and fifty-six of 175 consecutive patients who were admitted to our clinic between January 2000 and September 2002 due to a first episode of transmural AMI and who received thrombolytic therapy were enrolled. Coronary angiography was performed by the Judkins method on the 6th–10th day after the acute infarction. The corrected TIMI frame count (CTFC) was estimated according to the previously described method. According to the combination of the ST-segment and T-wave morphology on the day (6–10) of cardiac catheterization, patients were classified into four groups: group A, ST elevation 0.1mV and negative T waves; group B, ST elevation 0.1mV and negative T waves; group C, ST elevation 0.1mV and positive T waves; and group D, ST elevation 0.1mV and positive T waves. Of the 99 patients with negative T waves, 47 (48%) had CTFC 27, 32 (32%) CTFC between 27 and 40, 15 (15%) CTFC 40–100, and 5 (5%) CTFC 100. Of the 57 patients with positive T waves, CTFC was 27 in 14 (25%), between 27 and 40 in 17 (30%), 40–100 in 11 (19%), and 100 in 15 (26%) (P 0.001). From the 76 patients with an isoelectric ST segment, 38 (50%) had CTFC 27, 29 (38%) CTFC between 27 and 40, 8 (11%) CTFC 40–100, and 1 (1%) CTFC 100. Of the 80 patients with an elevated ST segment, 23 (29%) had CTFC 27, 20 (25%) CTFC between 27 and 40, 18 (23%) CTFC 40–100, and 19 (23%) CTFC 100 (P 0.001). Use of the combination of two electrocardiographic parameters (ST segment and T waves) also indicated that there were significant differences between groups A and D, and groups B and D (P 0.001 and P 0.05, respectively). Development of an isoelectric ST segment with negative T waves may indicate a better degree of reperfusion after AMI. In contrast, patients in whom ST-segment elevation and positive T waves remain at discharge from the coronary care unit have a higher probability of a nonpatent left anterior descending artery.     

Vorbestehendes Risikoprofil und Dekubitalulzera im intensivmedizinischen Bereich

Zusammenfassung In diesem Beitrag werden die Risikofaktoren zu Beginn des Krankhausaufenthaltes bei Patienten, die auf Intensivstationen ein Dekubitalulkus entwickelten, mit denen der Patienten verglichen, die auf Normalstationen ein Dekubitalulkus entwickelten.Im Rahmen einer prospektiven Erhebung wurde durch das Pflegepersonals von April 2003 bis April 2004 bei jedem Patienten am Tag der Aufnahme ein 29 Punkte umfassendes Risikoprofil dokumentiert. Ingesamt umfasst die Auswertung 49 904 Behandlungsfälle, von denen 5073 (10,2%) mindestens einen Tag auf einer Intensivstation verbrachten. Insgesamt entwickelten 94 Patienten während eines Intensivaufenthaltes ein neues Dekubitalulkus und 186 Patienten ohne einen Aufenthalt auf einer Intensivstation.Patienten, die auf einer Intensivstation ihr Druckulkus entwickelten, unterschieden sich im Alter, der Geschlechterverteilung und der Krankenhausverweildauer nicht von den Patienten, die ihr Druckulkus ohne Intensivaufenthalt entwickelten. Der Anteil der operierten Patienten war mit 72% nur gering höher als mit 60% bei den nicht intensivmedizinisch betreuten Patienten (p=0,046). Die mittlere Anzahl von Risikofaktoren zu Beginn des Krankenhausaufenthaltes war mit 10,0±5,7 im Vergleich zu 7,5±4,9 bei den Patienten, die ihr Druckulkus auf Normalstation entwickelten, erhöht (p=0,001).Bei den Intensivpatienten waren bereits bei Aufnahme die Risikofaktoren stark sedierende Medikamente, gefäßverengende Medikamente, Op-Dauer >60 Minuten, Fieber, Sepsis, Stuhl- und Urininkontinenz, Druckgefährdung durch Ableitungssysteme oder Fixierung, Störung des Druck-, Schmerz- oder Temperaturempfindens häufiger als bei Patienten, die unabhängig von einem Intensivaufenthalt ein Druckulkus entwickelten.Die vorgestellten Daten zeigen, dass Patienten, die während eines Aufenthalts auf einer Intensivstation ein Dekubitalulkus entwickelten, schon bei Aufnahme ins Krankenhaus ein erhöhtes Risiko aufweisen.für das Interdisziplinäre Dekubitus-Projekt     

Identification and characterization of novel mutations of the aspartoacylase gene in non-Jewish patients with Canavan disease

Canavan disease, an inherited leukodystrophy, is caused by mutationsin the aspartoacylase (ASPA) gene. It is most common among children of Ashkenazi Jewish descent but has been diagnosed in many diverse ethnic groups.Two mutations comprise the majority of mutant alleles in Jewish patients, while mutations in the ASPA gene among non-Jewish patients are different and more diverse. In the present study, the ASPA gene was analysed in 22 unrelated non-Jewish patients with Canavan disease, and 24 different mutations were found. Of these, 14 are novel, including five missense mutations (E24G, D68A, D249V, C152W, H244R), two nonsense mutations (Q184X, E214X), three deletions (923delT, 33del13, 244delA), one insertion mutation (698insC), two sequence variations in one allele ([10T>G; 11insG]), an elimination of the stop codon (941A>G, TAGTGG, X314W), and one splice acceptor site mutation (IVS1–2A>T). The E24G mutation resulted in substitution of an invariable amino acid residue (Glu) in the first esterase catalytic domain consensus sequence. The IVS1–2A>T mutation caused the retention of 40 nucleotides of intron 1 upstream of exon 2. The results of transient expression of the mutant ASPA cDNA containing these mutations in COS-7 cells and assays for ASPA activity of patient fibroblasts indicated that these mutations were responsible for the enzyme deficiency. In addition, patients with the novel D249V mutation manifested clinically at birth and died early. Also, patients with certain other novel mutations, including C152W, E214X, X314W, and frameshift mutations in both alleles, developed clinical manifestations at an earlier age than in classical Canavan disease.     

Primärer Formwandel der Thrombozyten in vitro

Zusammenfassung Bei der Untersuchung mit dem Interferenz-Kontrast-Mikroskop zeigen die Thrombozyten nach der Blutentnahme im Zitrat-Blut, -Plasma, Heparin- und EDTA-Blut innerhalb von 30–60 charakteristische, quantifizierbare FormverÄnderungen: Quellung, Bildung von Pseudopodien, kleinsten Vesikeln und Unebenheiten an der PlÄttchenoberflÄche. Dieser Formwandel wird durch niedrige Inkubationstemperaturen (4 C, 10 C) gegenüber Zimmer temperatur beschleunigt; bei 37 C lÄuft er verzögert ab. Durch mechanische Alteration bei der Blutentnahme ist eine überproportionale Zunahme von a priori formverÄnderten Thrombozyten im sofort-fixierten Venenblut induzierbar. In vitro ist der Formwandel teilweise, in vivo vollstÄndig oder fast vollstÄndig reversibel. Einige bekannte Aggregationshemmer führen in vitro und z. T. auch nach oraler und intravenöser Applikation zu einer mehr oder minder ausgeprÄgten Hemmung (Bencyclan, SH 869 ASS > D-Propranolol) des Formwandels nach der Blutentnahme. Bencyclan, SH 869 und D-Propranolol bewirken dabei in vitro eine charakteristische Änderung der PlÄttchenform mit Bildung von KugelplÄttchen. Diespontane, primÄre FormverÄnderung der Thrombozyten nach der Blutentnahme ist wahrscheinlich nicht identisch mit der ADP-induzierten (sekundÄren), shape change. Die FormverÄnderung der PlÄttchen beeinflu\t wahrscheinlich das Ergebnis verschiedener Thrombozytenfunktions-und Aggregationsteste. Die Formwandelkinetik von klinisch Gesunden und Hodgkin-Kranken unterscheidet sich signifikant. Es ist möglich, da\ die beschriebene Methode in der Zukunft klinische Bedeutung gewinnt.     

The efficacy of neuraminidase treatment in studies on red cell aging

Summary An in vitro system was developed to test the propensity of rat erythrocytes (RBC) toward phagocytosis by homologous peritoneal macrophages after in vivo aging or after in vitro surface modification. Old RBC obtained from erythrocyte populations separated into fractions on the basis of their density were found to be phagocytosed to a significantly greater extent than cells obtained from young cell fractions. Neuraminidase treatment of RBC resulted in extensive phagocytosis in comparison to control cells representing the whole population or old cells. Galactose oxidase treatment of neuraminidase treated RBC afforded no protection from uptake by macrophages. In contrast, treatment of RBC with neuraminidase immobilized on Sepharose 4B, leading to removal of up to 25% of the total membrane sialic acid, did not lead to phagocytosis above control values. These results indicate that extreme caution is necessary in the interpretation of experiments in which neuraminidase is utilized to produce simulated aged RBC.     

Flexibility of erythrocytes in juvenile diabetes mellitus

Summary The rheological properties of erythrocytes of 47 diabetic children and adolescents were studied. Deformability of red cells of 32 patients under poor metabolic control was markedly decreased while the deformability of red cells of patients (15 individuals) under good control was normal. This diminished flexibility of erythrocytes of patients under poor control can be explained partly by an increased concentration of free fatty acids in plasma. Moreover we found a decreased fluidity of the intracellular hemoglobin caused possibly by a decreased concentration of 2, 3-diphosphoglycerate in the cells.Supported by Deutsche Forschungsgemeinschaft     

Uptake and metabolism of radiolabelled GM1-ganglioside in skin fibroblasts from controls and patients with GM1-gangliosidosis

Summary The uptake and metabolism of [3-³H-sphingosine]GM1-ganglioside was measured in cultured skin fibroblasts from controls and patients with infantile, juvenile and adult GM1-gangliosidosis. When dissolved in medium with phosphatidylserine, GM1-ganglioside was efficiently taken up by cultured skin fibroblasts and transferred into lysosomes. A linear increase in GM1-ganglioside endocytosis was shown with phosphatidylserine concentrations of up to 40m/ml. A pulse-chase study revealed that [³H]GM1-ganglioside was metabolized to GM2-ganglioside, GM3-ganglioside, ceramide dihexoside, ceramide monohexoside, ceramide and sphingosine. Sphingosine was recycled to sphingomyelin. In a 20-h pulse study, cell lines from patients with GM1-gangliosidosis of infantile, juvenile and adult types hydrolysed 2–5%, 20–44% and 54–58% of the total endocytosed GM1-ganglioside respectively. These values were lower than in control cells (64.17 ± 5.43% (n=10)). The hydrolysis rates of exogenous [³H]GM1-ganglioside in cultured fibroblasts from patients with various types of GM1-gangliosidosis closely reflected the clinical severity.Abbreviations GM1 Gal13GalNAc14(NeuAc23)Gal14Galc-1-ceramide - GM2 GalNAc14(NeuAc23)Gal14Glc-1-ceramide - GM3 NeuAc23Gal14Glc-1-ceramide - CDH Gal14Glc-1-ceramide     

Protein kinase C expression in salivary gland acinar epithelial cells in non-obese diabetic mice,an experimental model for Sjögren''s syndrome

We planned to investigate the expression of protein kinase C (PKC) isoforms in acinar epithelial cells of salivary glands in the non-obese diabetic (NOD) mouse to find out if they develop changes of the PKC system like those seen in the human counterpart, i.e. in Sjögren's syndrome. Parotid, submandibular, and sublingual glands from NOD and control BALB/c mice were stained with a panel of monoclonal antibodies directed against conventional (, , and ), novel (, , and ), and atypical ( and ) PKC isoforms using the streptavidin/HRP method. Similarly to human labial salivary glands, acinar epithelial cells of the healthy control BALB/c mice contained two of the conventional PKC isoforms, and . Acinar and ductal epithelial cells also contained the atypical PKC isoforms and . PKC isoforms , , , and were not found. NOD mice which displayed focal sialadenitis contained the same conventional and atypical PKC isoforms. The acinar cells in NOD mice, in contrast to the Sjögren's syndrome patients, did not lack PKC or . On the contrary, PKC and staining was stronger than in the control BALB/c mice. The present results demonstrate that both conventional and atypical PKC isoforms participate in the salivary epithelial cell biology and that there are mouse strain-associated and/or disease state-associated changes in their expression. The lack of PKC and isoforms found in Sjögren's syndrome was not reproduced in NOD mice, which discloses one more difference between the human disease and its NOD mouse model.     

Selective A2A adenosine agonist ATL-146e attenuates acute lethal liver injury in mice

Background d-Galactosamine (GalN)/lipopolysaccharide (LPS)-induced liver injury is an experimental model of fulminant hepatic failure in which tumor necrosis factor- (TNF-) plays a pivotal role. We examined the effects of a highly selective adenosine A_2A receptor agonist (ATL-146e) on GalN/LPS-induced fulminant hepatic failure.Methods Mice were given an intraperitoneal dose of GalN (800mg/g body weight)/LPS (100ng/g body weight) with and without ATL-146e (0.01µg/kg) treatment. Liver injury was assessed biochemically and histologically. Also, TNF- levels in the serum were determined.Results The serum liver enzyme (ALT) level in vehicle-treated mice was 20960 ± 2800IU/ml and was reduced by 63% to 7800 ± 1670IU/ml by treatment with 0.01µg/kg per minute ATL146e, P < 0.05. Treatment with ATL-146e significantly reduced serum TNF- and greatly reduced inflammation assessed by histopathologic examination compared with control mice treated with GalN/LPS. ATL-146e also reduced lethality at 12h from 65% to 13%.Conclusion The present findings suggest that the highly selective adenosine A_2A receptor agonist (ATL-146e) prevents endotoxin-induced lethal liver injury by suppression of TNF- secretion.     

Untersuchungen zur Wechselwirkung zwischen aromatischen Kohlenwasserstoffen und Aminen mit Desoxyribonucleinsäure

Zusammenfassung Zur Untersuchung der Wechselwirkung mit DNA wurden Lösungen von hochmolekularer Kalbsthymus-DNA mit Dimethylformamid-Lösungen von zwölf krebserzeugend unwirksamen und wirksamen aromatischen Kohlenwasserstoffen und Aminen versetzt. Anschließend wurden die Lösungen dialysiert, mit organischen Lösungsmitteln extrahiert und zentrifugiert. Aus den UV-Spektren der Lösungen wurden bestimmt: a) aus den Banden der Aromaten oberhalb 300 m die Menge an gebundener Verbindung, b) die Extinktion bei 260 m als Maß für die in Lösung vorhandene DNA und durch Verfolgung der Extinktion bei Temperaturerhöhung der hyperchrome Effekt und der Schmelzpunkt der DNA. Beziehungen zwischen den erhaltenen Daten und der krebserzeugenden Wirksamkeit der Verbindungen wurden nicht gefunden. Ohne Effekt waren ferner Pyridino-[2,3:3,4]-phenoxazon-(2) und das Follikelhormon Östradiol(3,17 ). Bestätigt wurde die Wechselwirkung mit DNA für die Mutagene Proflavin und Acridinorange. Auffallend ist eine deutliche Erhöhung des Schmelzpunktes der DNA durch N-Phthalyl-glutaminsäure-imid.

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Summary Solutions of high molecular calf-thymus-DNA were mixed with dimethyl formamide solutions of 12 cancerogenic inactive and active aromatic hydrocarbons and amines in order to study the reciprocal effect with DNA. The solutions were then dialyzed, extracted with organic solvents, and centrifuged. From the UV spectra of the solutions the following were determined: (a) the amount of bound compounds from the bands of aromatics above 300 m; (b) the extinction at 260 m as a measure of the DNA present in the solution. By following the extinction with increases in temperature the hyperchrome effect and the melting point of DNA were determined. Relationships between the data obtained and the cancerogenic activity of the compounds were not found. In addition, pyridino-[2,33,4]-phenoxazon-(2) and the follicle hormone estradiol-(3,17 ) were without effect. The reciprocal effect of DNA with the mutagens, proflavin and acridine orange, was confirmed. A distinct increase of the melting point of DNA by means of N-phthalyl-glutaminic acid-imide was striking.

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Herrn Prof. Dr. K. H. Bauer zum 75. Geburtstag gewidmet.