[Laboratory diagnosis of lupus anticoagulant]

Lupus anticoagulant (LA) prolongs clotting times in vitro, but in vivo leads to an increased risk of thromboembolic complications. LA is detected in many patients with lupus erythematosus but also in subjects without any autoimmune disease (primary antiphospholipid syndrome). We determined LA in 133 patients, mostly with lupus erythematosus and other autoimmune diseases. Three screening and two confirmatory tests based on different mechanisms of clotting system activation were used. LA was found in 34 patients. DRVVT was the most useful test in detecting LA while kaolin clotting time was the least sensitive. Anticardiolipin antibodies (ACL) of IgG class were found in 41 patients studied (31%). They were most often detected in patient positive for LA (64%). ACL IgM were not associated with prolonged clotting times. Laboratory diagnosis of antiphospholipid syndrome is easy when the presence of LA is confirmed by two independent tests and in addition ACL would be detected. In other cases, when only single tests are positive, it is suggested to repeat diagnostic procedure at least once.

[Evan's syndrome with antiphospholipid-protein antibodies]

This is a case report of a 34 years old man with Evans syndrome associated with antiphospholipid-protein antibodies. They include lupus anticoagulant and antibodies against cardiolipin, prothrombin and beta 2-glycoprotein I, detected by ELISA. No thrombotic events were observed. The presence of several antibodies directed against surface cell membrane structures in Evans syndrome suggests a common pathogenetic mechanism.

[Prevalence of thrombosis in secondary antiphospholipid-protein syndrome]

Antiphospholipid-protein syndrome (APS) comprises venous and arterial thrombosis, spontaneous abortion and thrombocytopenia in patients with antiphospholipid-protein antibodies (APA). Such antibodies are detected by immunoenzymatic (ELISA) methods (e.g. anticardiolipin antibodies-ACL) or coagulation assays (lupus anticoagulant-LA). APS in patients showing other symptoms of autoimmune disease is called secondary antiphospholipid-protein syndrome. The aim of the study was to find relation between history of thrombosis and APA in a group of patients with lupus erythematosus and lupus-like disease. Lupus anticoagulant was detected by a three step procedure using phospholipid dependent clotting assays and anticardiolipin antibodies were measured by ELISA. We studied 95 subjects (91 women, 4 men) suffering from lupus erythematosus (67 patients) and lupus-like-disease (28 patients). Lupus anticoagulant was found in 26, anticardiolipin antibodies IgG in 34 and IgM in 27 subjects. In a retrospective study 40 thrombotic events were detected in 36 patients; deep vein thrombosis in 19, pulmonary embolism in 7, ischaemic CNS events in 13 and myocardial infarction in one. Thrombosis was present more often in subjects with LA (61%) and ACL IgG (52%) than in subjects without these antibodies (24%) (p = 0.004 and 0.015, respectively). ACL IgM antibodies were not related to thrombotic episodes. The ACL IgG antibodies and LA are helpful in identifying subjects at risk factors of venous and arterial thrombosis among patients suffering from lupus erythematosus and lupus-like disease.

Alteration of lung atrial natriuretic peptide receptors in genetic cardiomyopathy

These studies were designed to characterize the atrial natriuretic peptide (ANF) receptor subtypes [guanylyl cyclase natriuretic peptide receptors (NPR-A, NPR-B) and NPR-C] in lungs of normal hamsters and to evaluate alterations in receptor kinetics in genetic cardiomyopathy (CMO), a model of human congestive heart failure. Lung membranes were obtained from normal and CMO 200-to 230-day-old hamsters. Cross-linking and competitive binding receptor assays using 125I-labeled human ANF showed that lung membranes exhibit NPR, mainly guanylyl cyclase NPR-A and clearance NPR-C receptors. Stimulation of guanylyl cyclase by ANF and C-type natriuretic peptide (CNP) confirmed the presence of NPR-A and NPR-B. The maximum binding capacity of total ANF binding sites (442 +/- 68 vs. 271 +/- 57 fmol/mg protein, P < 0.05) was reduced, but dissociation constant (0.26 +/- 0.04 vs. 0.41 +/- 0.08 nM) was not altered in CMO animals. Similar reductions were observed in the binding sites for brain natriuretic peptide (BNP; 438 +/- 83 vs. 236 +/- 53 fmol/mg protein) and CNP (321 +/- 80 vs. 165 +/- 56 fmol/mg protein, P < 0.05) which may reflect a decline in NPR-A and NPR-B and/or NPR-C. Acid wash improved binding of 125I-labeled rat ANF to lung membranes of both normal and CMO hamsters, but the tendency towards reduced binding in CMO hamsters did not reach statistical significance, implying that downregulation may not have been due only to prior occupancy of the receptors. Transcripts of NPR-A, NPR-B, and NPR-C receptors in hamster lungs were detected by quantitative polymerase chain reaction. Compared with normal controls, the CMO hamster lung NPR-A mRNA was reduced by 50%, but NPR-B mRNA and NPR-C mRNA were not altered. Moreover, CMO hamster lungs showed less activation of guanylyl cyclase by ANF. These studies demonstrate that lung NPR are downregulated in hamster CMO.

Natriuretic peptide system in the rat submaxillary gland

Natriuretic peptides and their receptors were characterized in rat submaxillary glands (SGs). Reverse phase-high performance liquid chromatography (HPLC) of rat SGs extracts revealed the presence of the 28-amino-acid (AA) circulating peptide ANP (Ser99-Tyr126) and the 126-AA prohormone (Asn1-Tyr126). The presence of ANP prohormone indicated that SGs are a site of ANP synthesis. Indeed, ANP mRNAs were demonstrated. ANP mRNA was 10 times lower than in the lung and only about 7 times lower than in the hypothalamus. ANP content in SG was determined as 30 +/- 8 ng/mg of protein (n = 7). In addition the presence of another member of the natriuretic peptide family, C-type natriuretic peptide (CNP), was found in SG. The CNP level of 293 +/- 38 pg/mg protein was significantly higher than in the lungs (44 +/- 6 pg/mg protein, P < 0.001, n = 5), but about 15 times lower than in hypothalamus (4.5 +/- 0.6 ng/mg protein, P < 0.001, n = 6). Both guanylyl cyclase and clearance receptors were expressed in SG. The presence of natriuretic peptide transcripts and their receptors suggests a role in rat SG functions.

Renal atrial natriuretic factor receptors in hamster cardiomyopathy

Hamsters with cardiomyopathy (CMO), an experimental model of congestive heart failure, display stimulated renin-angiotensin-aldosterone and enhanced sympathetic nervous activity, all factors that lead to sodium retention, volume expansion and subsequent elevation of plasma atrial natriuretic factor (ANF) by the cardiac atria. However, sodium and water retention persist in CMO, indicating hyporesponsiveness to endogenous ANF. These studies were undertaken to fully characterize renal ANF receptor subtypes in normal hamsters and to evaluate whether alterations in renal ANF receptors may contribute to renal resistance to ANF in cardiomyopathy. Transcripts of the guanylyl cyclase-A (GC-A) and guanylyl cyclase B (GC-B) receptors were detected by quantitative polymerase chain reaction (PCR) in renal cortex, and outer and inner medullas. Compared to normal controls, the cardiomyopathic hamster's GC-A mRNA was similar in cortex but significantly increased in outer and inner medulla. Levels of GC-B mRNA were not altered by the disease. On the other hand, competitive binding studies, autoradiography, and affinity cross-linking demonstrated the absence of functional GC-B receptors in the kidney glomeruli and inner medulla. Also, C-type natriuretic peptide (CNP), the natural ligand for the GC-B receptors, failed to stimulate glomerular production of its second messenger cGMP. In CMO, sodium and water excretion were significantly reduced despite elevated plasma ANF (50.5 +/- 11.1 vs. 309.4 +/- 32.6 pg/ml, P < 0.001). Competitive binding studies of renal glomerular ANF receptors revealed no change in total receptor density, Bmax (369.6 +/- 27.4 vs. 282.8 +/- 26.2 fmol/mg protein), nor in dissociation constant, Kd (647.4 +/- 79.4 vs. 648.5 +/- 22.9 pM). Also, ANF-C receptor density (254.3 +/- 24.8 vs. 233.8 +/- 23.5 fmol/mg protein), nor affinity were affected by heart failure. Inner medullary receptors were exclusively of the GC-A subtype with Bmax (153.2 +/- 26.4 vs. 134.5 +/- 21.2 fmol/mg protein) and Kd (395.7 +/- 148.0 vs. 285.8 +/- 45.0 pM) not altered by cardiomyopathy. The increase in ANF-stimulated glomerular cGMP production was similar in normal and CMO hamsters (94- vs. 75-fold). These results demonstrate that renal ANF receptors do not contribute to the attenuated renal responses to ANF in hamster cardiomyopathy.

Characterization and distribution of natriuretic peptide receptors in the rat uterus

Atrial natriuretic peptide (ANP) receptors were characterized in rat uterus. The binding of [125I]ANP to uterine membranes was completely competed for by increasing concentrations of unlabeled ANP (Kd = 0.39 nM) and brain natriuretic peptide (Kd = 1.24 nM) and partially by C-type natriuretic peptide (CNP; Kd = 80.4 nM), but not by C-ANF. Also, [125I]Tyr-CNP bound to uterine membranes was completely competed by unlabeled CNP (Kd = 1.12 nM). Cross-linking of [125I]ANP to uterine membranes revealed the presence of one band of 130 kilodaltons, corresponding to the guanylyl cyclase (GC-A and/or GC-B) subtypes of natriuretic peptide receptors. The presence of messenger RNA coding for genes of both GC-A and GC-B receptors was shown by quantitative reverse transcriptase polymerase chain reaction. Furthermore, ANP and, to a lesser degree, CNP stimulated the production of cGMP in rat uterus. Autoradiographic studies localized the highest binding of [125I]ANP in the endometrium, whereas [125I]Tyr-CNP binding was distributed in the endometrium as well as in the myometrium. These results demonstrate that rat uterine ANP receptors are of the guanylyl cyclase-coupled subtypes. The uterus is a target of natriuretic peptides where ANP induces its biological effects through the production of cGMP.

[14-year experience with surgical treatment of chronic pancreatitis]

The authors discuss their own 14-year experience with surgical treatment of the chronic pancreatitis. They treated 64 patients of a mean age of 43 years. An abdominal pain, persisting in all patients, constituted the main indication to surgery. Forty patients underwent pancreatic enterostomy with Puestow technique, 19 patients resections of various extension, and 5 patients underwent pancreatic duodenostomy. Mortality rate in pancreatic enterostomy and pancreatic duodenostomy was 2.5% whereas mortality rate in resections was 5.3%. Complications were noted in 27.5% and 36.8% of patients, respectively. Pain was completely abolished or markedly reduced in 90% of patients. Forty eight (77.4%) out of 62 patients were identified and followed up. According to commonly used criteria, positive late results were achieved in 56.2% of patients, moderate in 29.2%, and poor result in 14.6% of the treated patients.

The Vin-1 gene, identified by provirus insertional mutagenesis, is the cyclin D2

The Vin-1 gene was initially identified as a gene whose expression is altered by the integration of proviruses in the Vin-1 common site of integration in retrovirus-induced rodent T-cell leukemias. We have now isolated the Vin-1 cDNA. Sequencing of the Vin-1 cDNA and Vin-1 exons revealed that the proviruses are integrated at the 5' end of the Vin-1 gene in an inverse transcriptional orientation. The sequence of the Vin-1 gene is identical to that of the recently identified G1-phase cyclin D2 gene. The human homolog of the Vin-1/cyclin D2 gene (CCND2) was mapped to chromosome 12, band p13.3, by in situ hybridization, confirming previous mapping data. Our results strongly support a role of the cyclin D2 gene in oncogenesis and thereby implicate altered cell cycle regulation in transformation.

IgG-subclass-specific antibody reactivity to respiratory syncytial virus polypeptides investigated by western blot

IgG1 and IgG3 subclass-specific antibody reactivity (ABR) in serum samples obtained from infants and children in relation to acute lower respiratory disease caused by respiratory syncytial virus (RSV) infection was investigated by Western blot. IgG1 ABR was directed against the nucleocapsid polypeptides VPN and VPP as well as against the glycoproteins GP48 (F1) and GP90. IgG3 ABR was directed only against VPN and VPP. In infants, a low IgG1 reactivity against glycoproteins was observed. When serum samples obtained in the early convalescent phase were tested, ABR against GP48 and GP90 as well as against VPP differed with respect to RSV subtypes A and B. IgG1 ABR increased in the late convalescent phase, while IgG3 ABR decreased during this phase when serum samples from primary infections were tested.

Sensitive enzyme immunoassay for the rapid diagnosis of influenza A virus infections in clinical specimens

Samples of nasopharyngeal secretion (NPS) from 100 infants and small children admitted for acute respiratory disease during the period from January to March 1989 were examined for the presence of influenza A virus. All samples were tested by enzyme immunoassay (EIA), fluorescent antibody (FA) technique and by isolation in cell culture 3-6 h after they were obtained from the patients. Of 24 influenza strains found by isolation, 21 were detected by EIA and 19 were FA+. In comparison with virus isolation, EIA gave the following values: sensitivity 88%, specificity 100%, positive prognostic value (PPV) 100%, and negative prognostic value (NPV) 96%. A rabbit anti-influenza-A serum (A-13) was used as catching antibody and a monoclonal anti-influenza-A pool against NP protein was used as detector antibody in EIA. A-13 gave bands corresponding to influenza A core proteins (NP and M1) in Western blot (WB) studies when different H3N2 strains were employed as antigens. A-13 gave only a band corresponding to the NP protein when H1N1 strains were examined by WB. The detection level by EIA for both H3N2 and H1N1 strains precipitated by polyethylene glycol from tissue culture maintenance medium was 1-2 ng.

[Respiratory viral infections in young children 1988-1990]

From October 1988 to June 1989 the studies on viral infections of respiratory tract were done in specimens taken from 461 children, aged 0-2 years. Similarly to the observations in previous epidemic seasons infections due to RS and parainfluenza type 3 viruses were dominated. These studies included also influenza type C and parainfluenza type 4 viruses with unknown epidemiology in Poland. The insignificant role of these infections in small children was estimated according to the low ratio of detection in specimens tested--0.4% and 0.9% respectively.

[Clinical aspects of herpes simplex meningoencephalitis]

On the basis of the observed 10 cases the authors discuss the diagnostic, clinical and therapeutic problems of herpes encephalomeningitis. The diagnosis in early phase of the disease but already after appearance of psychic and neurological symptoms and signs is based on clinical criteria and also on the result of examination of the cerebrospinal fluid and rapid serological method ELISA. In view of the already available possibilities of virostatic treatment early diagnosis is of utmost importance, for beginning treatment (preferably with Vidarabine) before the development of extensive necrotic brain lesions.

Cell-mediated immune reactions in measles

Cell-mediated reactions in measles cases, in direct contacts and healthy children were tested. Indices of phytohaemagglutinin-stimulated blastic transformation and leukocyte migration inhibition were evaluated. Positive reactions were found in the first and second weeks after manifestation of clinical symptoms. The application of glucocorticosteroids in clinical complications resulted in delayed and reduced leukocyte migration inhibition. Studies on seronegative contacts suggested that positive cell-mediated reactions may appear before manifestation of clinical symptoms.

Estimation of antibodies to human cytomegalovirus by immunofluorescence and radioimmunoassay

The 125J labeled IgG fraction against rabbit IgG of goat origin was employed for the detection of CMV IgG and IgM antibodies in the double indirect radioimmunoassay. The results were compared with those obtained in complement fixation, indirect immunofluorescence and anti-complement immunofluorescence tests. The application of labeled anti-fc antisera, instead of antisera against whole IgG in the tests for detection of specific CMV IgG antibody resulted in increased sensitivity of radioimmunoassay and reduction of non-specific cytoplasmatic reactions in preparations stained by indirect immunofluorescence. The absorption of sera with protein A rich staphylococci and aggregates to immunoglobulin eliminated unwanted secondary IgM staining caused by rheumatoid factors both in indirect immunofluorescence and radioimmunoassay tests for CMV antibodies.