Detection of anti-bovine β2-glycoprotein I antibody in sera from patients with antiphospholipid syndrome

We studied and characterized anti-bovine ₂ I antibodies (aB₂-GPI) in sera from patients with antiphospholipid syndrome (APS) by ELISA. Bovine ₂-glycoprotein I ₂-GPI was purified by heparin affinity and DEAE ion-exchange chromatography, and identified on immunoblots using a monoclonal antibody against human ₂-GPI and by amino acid sequence analysis. aB₂-GPI levels in the sera from 36 APS patients were measured by ELISA using purified bovine ₂-GPI as an antigen. The mean±standard deviation level of aB₂-GPI was 17.4±22.0 units in the 58% of APS patients who were positive. There was a significant correlation (P=0.003) between aB₂-GPI and anticardiolipin antibody (aCL) levels. aB₂-GPI from the sera of patients with APS was inhibited by bovine ₂-GPI itself. Purified IgG from the sera of patients with APS showed that bovine ₂-GPI was capable of acting as a cofactor for aCL. Purified bovine ₂-GPI was useful antigen for conventional ELISA. aB₂-GPI may contribute to the further development of aCL analysis and to the understanding of the pathogenesis of APS.     

Expression and secretion of alpha1-proteinase inhibitor are regulated by proinflammatory cytokines in human pancreatic islet cells

Aims/hypothesis Alpha1-proteinase inhibitor (1-PI) has been considered a key player in inflammatory processes. In humans, the main production site of 1-PI is the liver, but other tissues, including pancreatic islets, also synthesise this molecule. The aims of this study were to assess the islet cell types that produce 1-PI, to determine whether 1-PI is actually secreted by islet cells, and to assess how its production and/or secretion are regulated.Methods Expression of 1-PI in human islet cells was assessed by immunofluorescence, electron microscopy and western blotting. Release of 1-PI was analysed by reverse haemolytic plaque assay and ELISA. The effects of cytokines on 1-PI synthesis and secretion were tested.Results Immunofluorescence showed that alpha and delta cells do express 1-PI, whereas beta cells do not. By electron microscopy, we demonstrated a colocalisation of 1-PI with glucagon and somatostatin within secretory granules. Immunolabelling also revealed localisation of 1-PI within the Golgi apparatus, related vesicles and lysosomal structures. The expression of 1-PI in islet cells was also demonstrated by western blotting and ELISA of protein extracts. ELISA and reverse haemolytic plaque assay showed that 1-PI is secreted into the culture medium. Treatment of islet cells with IL-1 and oncostatin M for 4 days increased the production and release of 1-PI.Conclusions/interpretation Our results demonstrate that 1-PI is expressed by the alpha and delta cells of human islets, and that proinflammatory cytokines enhance the production and release of this inhibitor.     

γ/δ Receptor-expressing T-cell clones from a cutaneous T-cell lymphoma suppress hematopoiesis

Summary Recently we described a cutaneous T-cell lymphoma expressing the / T-cell receptor [5]. The patient suffering from this lymphoma showed low numbers of myeloid and T cells in peripheral blood, while B and NK cells were relatively increased. In vitro culture of the patient's bone marrow (BM) cells revealed a significant suppression of myeloid/monocyte colony formation (GM-CFU) compared with normal controls. This was not due to infiltration of the BM with lymphoma cells. We speculated that a soluble factor either secreted or induced by the lymphoma cells might be responsible for the marked suppression of hematopoiesis in this patient. From a skin biopsy with infiltrating / T-lymphoma cells we established T-cell clones bearing the / T-cell receptor and resembling the phenotype of the lymphoma cells. The supernatant (SN) of these / T-cell clones reduced the number of colonies in a CFU-GM assay (using normal control BM) in comparison to SN of / T-cell clones established from the same biopsy. This suppression was seen mainly on day 7 of culture and was not neutralized by the addition of placenta-CM. The main mediator of this suppression seems to be IFN-,since it was detectable in high amounts in the SN of these / T-cell tumor clones as well as in the serum of the patient. In addition, anti-IFN- antibodies can reverse the T-cell SN-mediated suppression of CFU-GM. We conclude that high serum levels of interferon-, which is secreted in high amounts from / T-cells grown from a biopsy of a cutaneous lymphoma, can suppress hematopoiesis.Abbreviations TCR T-cell receptor - IFN- interferon- - SN supernatant - placenta CM placenta conditioned medium - BM bone marrow - CFU-GM myeloid/monocyte colony formation - NK cells natural killer cells - Ab antibody M. Wilhelm was supported by theDeutsche Forschungsgemeinschaft (DFG Wi 728-2)     

Granulocyte elastase in assessment of severity of acute pancreatitis

Complexes of granulocyte elastase and ₁-antitrypsin are markers for granulocyte activation. In 75 patients with acute pancreatitis these complexes were immunologically determined daily in plasma during the first week of hospitalization. Patients were classified into three groups: mild pancreatitis (I, 1 complication, N=34), severe pancreatitis (II, 2 complications, N= 29), lethal outcome (III, N=12). Initially, granulocyte elastase (mean±sem) was lower in group I (348±39 g/liter) as compared to groups II (897±183 g/l) and III (799±244 g/liter), P<0.001 for I vs II + III. Initial elastase concentrations >400 g/liter were consistent with a severe or fatal course of the disease but did not distinguish between severe and lethal pancreatitis. In patients with mild or severe disease, mean elastase concentrations decreased continuously during the following days (197±15 g/liter in mild cases, 325±30 g/liter in severe cases at day 7). In patients with lethal disease, however, mean elastase concentrations even increased at day 2 and remained higher than 700 g/liter during the observation period. At days 1 and 2 the predictive value for severe or lethal disease of raised (>400 g/liter) elastase concentrations [positive predictive value (PPV) 82%, negative predictive value (NPV) 81%] was better than that of elevated (>100 mg/liter) C-reactive protein (PPV 73%, NPV 73%), elevated (>4.0 g/liter) ₁-antitrypsin (PPV 59%, NPV 50%), or decreased (<1.5 g/liter) ₂-macroglobulin (PPV 82%, NPV 67%). When the time course of the concentrations of the acute-phase proteins was studied, it was found that rises of granulocyte elastase were followed by elevated C-reactive protein levels after one day, by elevated ₁-antitrypsin levels after two days and by decreased ₂-macroglobulin levels after three to four days. We conclude that granulocyte elastase is a good early marker for the severity of acute pancreatitis. Compared with elevated levels of C-reactive protein and ₁-antitrypsin release of granulocyte elastase reflects an event that precedes acute-phase protein induction.     

Fecal α1-antitrypsin detection of colorectal neoplasia

Fecal ₁-antitrypsin measurement may be of value for the detection of coloreactal neoplasia and is compared with the HemoQuant test in 119 subjects with either a screen-positive Hemoccult result (N=78) or iron-deficiency anaemia (N=41). Nineteen patients were found to have coloreactal cancer, 35 had colorectal adenomatous polyps, 5 had inflammatory bowel disease, and 60 had no detected cause of occult blood loss. Of the cancer patients, 63% (12/19) were detected by fecal ₁-antitrypsin, and 63% (12/19) by HemoQuant. Of the adenomas >1 cm in diameter 33% (7/23) were detected by fecal ₁-antitrypsin and 26% (6/23) by HemoQuant. There was a poor correlation between fecal ₁-antitrypsin, and HemoQuant results for colorectal cancers (r=0.37,P>0.05), and combining the tests, the sensitivity for colorectal cancer was incerased to 84% (16/19). Fecal proteins loss, as measured using ₁-antitrypsin, appears to involve largely different mechanisms from that of blood loss from colorectal cancers.     

Expression and prognostic roles of integrins and interleukin-1 receptor type I in patients with ductal adenocarcinoma of the pancreas

To Investigate the prognostic indicator, we examined the expression of ₆- and ₅- integrin and interleukin-1 receptor type I (IL-1RI) immunohistochemically, and analyzed the correlation between immunohistochemical findings and clinicopathological factors in pancreatic cancer. In patients with a strongly expressing ₆- integrin subunit or weakly expressing ₅₁-integrin in pancreatic cancer tissues there was a significant association with advanced TNM stage (P = 0.027 and 0.014, respectively), presence of liver metastases (P = 0.032 and 0.002, respectively), and poor prognosis (P = 0.0155 and 0.0056, respectively). In patients with a weakly expressing ₆ integrin subunit or weakly expressing ₅₁-integrin in noncancerous pancreatic tissues there was a significant association with poor prognosis (P = 0.0324 and 0.0396, respectively). Multivariate analysis demonstrated that strong expression of ₆- and weak expression of ₅₁-integrin were found to be independent prognosticators in pancreatic cancer patients. Our present results indicate that ₆₁- and ₅₁-integrin expression can be a significant prognostic indicator in pancreatic cancer.     

Rapid detection of −α 4.2 deletion of α-thalassemia-2 by polymerase chain reaction

Summary We sequenced part of the X boxes of-thalassemia-1 of Southeast Asia type (- -SEA) with– ^4.2,– ^3.7,– ^G-Taichung, and ^CS. We found the X box of– ^3.7 belonged to the X box of 2 globin gene and the X box of ^cs contained X boxes of both al and2 globin gene, whereas the X box of– ^4.2 and– ^G-Taichung was a hybrid of X boxes of 2 and 1 globin gene. We also found there are two types of– ^4.2 deletion; type 1 is a common type of– ^4.2 deletion and type 2 is linkage to– ^G-Taichung. We used a combination of two methods, the amplification refractory mutation system (ARMS) and the amplified created restriction sites (ACRS), to amplify the hybrids of X boxes specifically. The upstream primer for X box of2 globin gene was designed following the standard ARMS procedure to amplify the X segment of the-globin gene. The downstream primer was designed according to the ACRS method to check the specificity of PCR products. Using this approach, we can diagnose the different types of– ^4.2 deletion. This kind of approach can also be used to amplify the specific region from the cluster of highly homologous genes.     

Pharmacological evidence for beta3 adrenoceptors in the control of rat gastric acid secretion

The effect of the ₃-adrenoceptor agonist BRL37344 on gastric acid secretion evoked by different secretory stimuli was investigated in anaesthetized rats with lumen-perfused stomachs in comparison with the ₂-adrenoceptor agonist clenbuterol. Intravenous injections of BRL37344 (1–10 mol/kg) and clenbuterol (0.01–1 mol/kg) dose-dependently reduced 2-deoxy-D-glucose-induced acid secretion, with BRL37344 about forty times less potent than clenbuterol. BRL37344 (0.1–3 mol/kg) inhibited pentagastrin-induced acid output, whereas clenbuterol was effective only at high doses (10–100 mol/kg). The inhibitory effect of BRL37344 on pentagastrin-induced acid secretion was not modified by the nonselective –adrenoceptor antagonist propranolol, but it was prevented by bupranolol, a ₃-adrenoceptor antagonist. Furthermore, neither BRL37344 (10 mol/kg) nor clenbuterol (100 mol/kg) modified the acid secretion induced by histamine. These data suggest that ₃ adrenoceptors have an inhibitory role in the control of rat gastric acid secretion induced by indirect stimuli.     

Plasma levels of human granulocytic elastase α1-proteinase inhibitor complex (E-α1-PI) in leukemia

Summary There is evidence that polymorphonuclear granulocytes release neutral proteinases such as elastase (E) and cathepsin G in the course of acute leukemia. These proteinases may inactivate clotting factors by unspecific degradation before they are eliminated via complex formation with endogenous inhibitors, e. g. the ₁-proteinase inhibitor (₁-PI). In this study it was attemped to correlate plasma levels of the E-₁-PI complex with factor XIII and antithrombin III in acute leukemia. Using a newly developed, sensitive enzyme-linked immunoassay the concentration of E-₁-PI in patients with various types of leukemia, malignant lymphoma or multiple myeloma was determined. Only patients with acute myelocytic or promyelocytic leukemia (AML, APL) and chronic myelocytic leukemia with and without blastic transformation (CML) showed moderate to high levels of E-₁-PI (2- to 20-fold of normal). However, coagulation factor concentration observed in the different types of leukemia seemed to be independent of elastase liberation. Most of the AML-patients with elevated E-₁-PI levels showed peroxidase positive blood cell smears.     

Plasma 6-keto-PGF1α, thromboxane B2 and PGE2 in Type 1 (insulin-dependent) diabetic patients during exercise

Summary The capacity of prostacyclin production determined as plasma 6-keto-PGF₁ was investigated in 12 Type 1 (insulin-dependent) diabetic patients with a median duration of diabetes of 14 years during ordinary metabolic control. Using high pressure liquid chromatography preceding radioimmunoassay, the plasma concentration of 6-keto-PGF₁, the stable metabolite of prostacyclin, was determined at rest and after a standardised bicycle exercise test. The plasma 6-keto-PGF₁ in diabetic patients at rest did not differ from that of 25 healthy volunteers; 2.9 pg/ml (range<0.2–15.3) versus 1.7 pg/ml (range<0.2–16.6). During the exercise test plasma 6-keto-PGF₁ increased significantly in the diabetic patients as well as in the control group (p< 0.05). The increment of 6-keto-PGF₁ in the diabetic patients was neither related to the metabolic regulation, duration of diabetes nor to changes in platelet volume, platelet number or the production of thromboxane B₂ and prostaglandin E₂. Our results do not support the hypothesis that Type 1 diabetic patients have a decreased capacity of prostanoid production, as suggested from in vitro studies.     

Serumglykoproteine beim Diabetes mellitus; quantitative immunologische Bestimmung von saurem α1-Glykoprotein,Gc, α2-Makroglobulin und Hämopexin bei Diabetikern mit und ohne Angiopathien

Zusammenfassung 1. Bei Diabetikern mit und ohne Gefäßkomplikationen wurden die Serumkonzentrationen des sauren ₁-Glykoproteins, der gruppen-spezifischen Komponente (Gc), des ₂-Makroglobulins und des Hämopexins mit der Immuno-Diffusions-Methode nachMancini und Mitarb. quantitativ bestimmt. — 2. Das ₂- Makroglobulin ist bei Diabetikern vermehrt, bei 276 Patienten fand sich ein Mittelwert von 242 mg% gegenüber einem Mittelwert von 186 mg% bei 98 nicht-diabetischen Blutspendern. Diese Differenz ist statistisch hochsignifikant. Der Konzentrationsanstieg ist bei jugendlichen Diabetikern stärker ausgeprägt als bei Altersdiabetikern. Bei Patienten mit Retinopathie findet sich eine deutlichere Vermehrung als bei Patienten ohne Retinopathie. Auch geht der Anstieg des ₂-Makroglobulins mit dem Schweregrad arteriosklerotischer Veränderungen der peripheren Gefäße parallel. — 3. Die Konzentrationen des sauren ₂-Glykoproteins und der gruppen-spezifischen Komponente sind in Seren von Diabetikern gegenüber gesunden Blutspendern nur unwesentlich vermehrt. — 4. Die Hämopexin Konzentration ist bei Diabetikern mit einem Mittelwert von 92 mg% gegenüber gesunden Blutspendern mit einem Mittelwert von 77 mg% gering erhöht; dieser geringe Unterschied ist statistisch hochsignifikant.

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Serum, glycoproteins in diabetes mellitus; quantitative immunological determination of acid ₁-glycoprotein, Gc, ₂-macroglobulin and haemopexin in diabetics with and without angiopathy

Summary 1. Serum concentrations of acid ₁-glycoprotein, Gc, ₂-macroglobulin and haemopexin were determined in diabetics with and without vascular complications by the immunological assay method ofMancint and co-workers. — 2. ₂-macroglobulin concentrations were increased in sera of diabetics. The mean value was 242 mg% in 276 patients compared with the mean value of 186 mg% in a sample of 98 healthy blood-donors. This difference is statistically highly significant. The increase was more pronounced in juvenile diabetes than in late-onset diabetes. The increase was also more pronounced in patients with retinopathy than in patients without retinopathy. There was also an increase of ₂- macroglobulin concentrations in relation to the degree of arteriosclerotic changes of the peripheral vessels. — 3. Serum concentrations of acid ₁-glycoprotein and Gc were only slightly increased in diabetics compared with blood-donors. — 4. There was a small, but statistically highly significant increase of haemopexin concentrations in sera of diabetics. The mean value in 243 diabetics was 92 mg%, in 15 healthy blood-donors a mean value of only 77 mg% was found.

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft     

α2-Macroglobulin as an inclusion in synovial fluid monocytes

Summary By the immunofluorescence method, inclusions of ₂-macroglobulin (₂M) were demonstrated in synovial fluid monocytes but not neutrophils. They were more frequent in more inflammatory fluids. By in vitro experiments using both mouse peritoneal cells and human peripheral mononuclear cells, it was demonstrated that these inclusions probably correspond to ₂M-protease complexes, which are specifically taken up and destroyed by macrophages in exudates.     

Heterophilic interactions between cell adhesion molecule L1 and α<Subscript>v</Subscript> β<Subscript>3</Subscript>-integrin induce HUVEC process extension <Emphasis Type="Italic">in vitro</Emphasis> and angiogenesis <Emphasis Type="Italic">in vivo</Emphasis>

Cell adhesion molecule L1 was implicated in angiogenic processes, tumor formation and metastasis. Here, we provide evidence that the sixth Ig-like domain of L1 (L1Ig6) interacts with _{v 3} to induce process extension of human umbilical vein endothelial cells (HUVECs) in vitro and angiogenesis in vivo. HUVECs formed network-like structures on full-length L1 or L1Ig6 substrates comparable to structures found on matrigel. In the presence of mab _{v 3} or cyclic RGD, apoptosis was induced. In fibrin matrices where L1Ig6 was covalently incorporated, HUVECs formed multicellular and hollow processes through interactions between cell-surface _{v 3} and RGD-sites of matrix-immobilized L1Ig6. No such processes were induced by L1Ig6 having non-functional RDG-sites, or in the presence of mab _{v 3} or cyclic RGD. In those matrices, increased apoptosis was found. Co-immunoprecipitation of L1 or L1Ig6 with _{v 3} suggests close interactions. Furthermore, L1Ig6 stimulated HUVECs showed increased tyrosine phosphorylation of _{v 3} and phosphorylation of MAP kinases (ERK1 and ERK2) but not AKT indicating specific activation of _v and _{v 3} followed by activation of downstream kinases. Application of L1Ig6-modified fibrin matrices on CAMs induced 50–60% increased _v and _v3 protein expression and in vivo angiogenesis indicated by ~50% increased mean vascular length density. The results demonstrate angiogenic potential of L1Ig6 involving ligation and activation of _v3     

Histological Effect of (R)-α-Methylhistamine on Ethanol Damage in Rat Gastric Mucosa (Influence on Mucus Production)

(R)--Methylhistamine, a selective agonistof histamine H₃ receptors, preventsmacroscopically visible gastric lesions by absoluteethanol in the rat. A further insight into its activitywas the aim of our study. Rats were given saline or(R)--methylhistamine (100 mg/kg)intragastrically. After 30 min, absolute ethanol wasgiven and gastric mucosa was sampled 60 min later.Histologic damage and intracellular and adherent mucus werequantified. Luminal surface and mucous cells wereexamined by scanning and transmission electronmicroscopy. (R)--Methylhistamine reduced theextent of lesions by ethanol from 96 to 18%. Surface mucous cellsand mucous neck cells were increased in volume andnumber, packaging of intracellular mucus was modified,and the secretory processes were promoted by(R)-methylhistamine itself, although these modifications weremostly evident in stomachs subsequently exposed toethanol. Adherent mucus layer thickness was increased by(R)-methylhistamine only after ethanol exposure. It is concluded that(R)--methylhistamine predisposes mucous cells toreact to ethanol.     

Increased serum levels of transforming growth factor-α in patients with colorectal cancer

PURPOSE: This study was conducted to investigate the serum levels of transforming growth factor- in patients with colorectal cancer and to investigate the clinical significance of these levels in association with tumor stage and histologic differentiation. Also, serum levels of transforming growth factor- were measured after curative surgical resection. METHODS: Serum levels of transforming growth factor- were measured in 42 consecutive patients with colorectal cancer before surgery, in 21 patients after surgical resection (part of the 42 preoperative patients), and in 20 healthy volunteers. We used TGF- Assay. RESULTS: Serum levels of transforming growth factor- in patients with colorectal cancer were significantly higher than in the healthy control group (P=0.001). Significant elevations in serum levels of transforming growth factor- were found in 50 percent (21/42) of patients with colorectal cancer when the mean + 2 standard deviations (80.4 pg/ml) of the control group were used as the upper limit of the normal range. Serum levels of transforming growth factor- tended to decrease with increasing tumor size (n=31;r=–0.52;P=0.002). Serum levels of transforming growth factor- before surgery (89.7±44.4 pg/ml; n=21) significantly decreased to 60.3±19.8 pg/ml after surgical resections of tumors (P=0.017). Serum levels of transforming growth factor- completely decreased to the same serum levels of the control group after surgical resections in all patients who had serum levels of transforming growth factor- greater than mean + 2 standard deviations (80.4 pg/ml) of the control group preoperatively (n=11;P=0.002). CONCLUSIONS: Levels of preoperative transforming growth factor- in patients with colorectal cancer appeared to be higher than levels measured in control subjects. Serum levels of transforming growth factor- before surgery significantly decreased after surgical resections of tumors. Additional studies are warranted to determine if serum levels of transforming growth factor- may be useful as a potential biomarker in the management of patients with colorectal cancer.Supported by a grant from Ewha Womans University Mokdong Hospital, Seoul, Korea.Read at the meeting of The American Society of Colon and Rectal Surgeons, Philadelphia, Pennsylvania, June 22 to 26, 1997.     

Effect of α-methylnorepinephrine,an α2-adrenergic agonist,on jejunal absorption in neurally intact conscious dog

Although ₂-adrenergic agonists stimulate absorption in the mammalian small and large intestinein vitro, the possibility of central neural effects have confounded interpretation ofin vivo studies. Our aim was to assess the effects of intravenous administration of -methylnorepinephrine (MNE), and ₂-adrenergic agonist that does not cross the blood-brain barrier, on net jejunal absorption of water and electrolytes in the neurally intact, conscious dog. Absorption from a 30-cm proximal jejunal segment was studied using a triple-lumen perfusion technique in seven dogs. A warmed, isosmolar, balanced electrolyte solution containing [¹⁴C]polyethylene glycol was infused at 5 ml/min. Net jejunal fluxes of water and electrolytes were determined before, during, and after a 1.5-hr infusion of MNE (900 nmol/kg/hr). MNE increased net jejunal water absorption (from 12.9±1.8 to 22.5±1.5 l/cm/min,P<0.05). Peripheral ₂-adrenergic receptors mediate a net proabsorptive response in the neurally intact canine jejunumin vivo independent of direct central neural effects.Parts of this work were published as an abstract inGastroenterology (100:A689, 1991). Supported in part by the United States Surgical Corporation, a grant provided by Harry S. Tan, and USPHS NIH grant DK39337 (M.G.S.).     

Gabexate mesilate, a synthetic protease inhibitor, attenuates carbon tetrachloride-induced liver injury in rats

Background Gabexate mesilate, a synthetic protease inhibitor, is used to treat acute pancreatitis and disseminated intravascular coagulation because it inhibits various serine proteases; however, whether gabexate mesilate prevents acute liver failure has not yet been studied. The aim of the present study was to investigate the effect of gabexate mesilate in carbon tetrachloride (CCl₄)-induced liver injury in rats.Methods Acute hepatic failure was induced by administration of CCl₄ intragastrically to male Sprague–Dawley rats. The effects of gabexate mesilate were examined in terms of serum transaminase levels, liver histology, and the prognosis of rats.Results Gabexate mesilate treatment significantly decreased the elevation of serum transaminase levels and improved liver histology 24h after the administration of CCl₄ (0.2ml/100g rat weight). Plasma tumor necrosis factor- (TNF-) and interleukin-1 (IL-1) decreased significantly in the gabexate mesilate-treated rats compared with saline-treated rats. Gabexate mesilate treatment also significantly improved survival rate after a lethal dose of CCl₄ (0.5ml/100g rat weight) from 0% to 20%.Conclusions Gabexate mesilate treatment attenuated CCl₄-induced liver injury via a suppression of proinflammatory cytokine production. In addition, these investigations suggest that gabexate mesilate treatment may provide therapeutic strategies for human acute liver failure.     

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.     

Pharmacological basis for duration of effect: Formoterol and salmeterol versus short-acting β2-adrenoceptor agonists

The mechanisms behind the long duration of bronchodilating action of the ₂-adrenoceptor agonists formoterol and salmeterol are only partially understood. This review compares pharmacological characteristics of long-acting versus short-acting ₂-adrenoceptor agonists in human and animal airways. Based upon the reviewed evidence, it is concluded that for ₂-adrenoceptor agonists, long duration of action may depend upon several factors. Both formoterol and salmeterol display a higher lipophilicity and have a higher affinity, selectivity, and potency than most short-acting agonists at the ₂-adrenoceptor. Of these factors, lipophilicity may prove to be one of the most important ones by determining the amount of drug entering into the cell membrane in the vicinity of the ₂-adrenoceptor. However, the receptor affinity, maximal relaxant effect (efficacy or intrinsic activity), potency, and receptor selectivity may also be of importance in determining how much ₂-adrenoceptor agonist must remain at the receptor for sustained action.     

Triplication (/ααα<Superscript>Anti3.7</Superscript>) or deletion (-α<Superscript>3.7</Superscript>/) association in Argentinian β-thalassemic carriers

Prevalence of alpha gene triplication or deletion in -thalassemia carriers was studied in 109 unrelated individuals in Rosario, Argentina. In different populations -^3.7 allele presents a higher prevalence than ^anti3.7; thus, -thalassemia associated with -thalassemia is more frequently observed. Nevertheless, this event was detected in only one case (0.9%), while the association with alpha triplication was present in two subjects (1.8%).