Pancreatic adenocarcinomas with DNA replication errors (RER+) are associated with wild-type K-ras and characteristic histopathology. Poor differentiation, a syncytial growth pattern, and pushing borders suggest RER+.

The clinical and pathological features of carcinomas of the pancreas with DNA replication errors (RER+) have not been characterized. Eighty-two xenografted carcinomas of the pancreas were screened for DNA replication errors using polymerase chain reaction amplification of microsatellite markers. Cases with microsatellite instability in at least two markers of a minimum of five tested were considered RER+. RER status was correlated with histological appearance, karyotype of the carcinomas when available, K-ras mutational status, and patient outcome. Three (3.7%) of the eighty-two carcinomas were RER+. In contrast to typical gland-forming adenocarcinomas of the pancreas, all three RER+ carcinomas were poorly differentiated and had expanding borders and a prominent syncytial growth pattern. Neither a Crohn's-like lymphoid infiltrate nor extracellular mucin production were prominent. Ductal adenocarcinomas of the pancreas typically contain a mutant K-ras gene, yet all three RER+ carcinomas had wild-type K-ras. One of the three RER+ carcinomas was karyotyped and showed a near diploid pattern. All three of the RER+ tumors were removed via Whipple resection. One of the three patients is free of disease 16 months after pancreaticoduodenectomy, one is alive and free of tumor at 52 months but developed two colon carcinomas during this period, and the third died of pancreatic cancer at 4 months. None of the three patients had a family history of colorectal carcinoma. A review of the K-ras wild-type carcinomas in a previously characterized series of pancreatic carcinomas with known K-ras mutational status identified two additional cancers with poor differentiation, a syncytial growth pattern, and pushing borders. Both of the cancers were diploid and both patients were longterm survivors (over 5 years). The inclusion of such patients in previous prognostic studies of pancreas cancer may explain the failure of histological grade to be a predictor of prognosis. These data suggest that DNA replication errors occur in a small percentage of resected carcinomas of the pancreas and that wild-type K-ras gene status and a medullary phenotype characterized by poor differentiation, and expanding pattern of invasion, and syncytial growth should suggest the possibility of DNA replication errors in carcinomas of the pancreas.     

Identification of a galactose-binding lectin on Fusobacterium nucleatum FN-2.

A previous study has suggested that Fusobacterium nucleatum FN-2 contains a galactose-binding protein (lectin) on the cell surface (P. A. Murray, V. Matarese, C. I. Hoover, and J. R. Winkler, FEMS Microbiol. Lett. 40:123-127, 1987). In the present study, the molecular specificity and size of this lectin were investigated by several techniques. Whole-cell affinity chromatography with asialofetuin covalently coupled to Sepharose 6MB demonstrated that 81% of 3H-labeled F. nucleatum were specifically eluted by 0.5 M galactose. Specific binding was calcium dependent and did not occur in the presence of calcium chelators. Binding was inhibited by preincubation with galactose. Agglutination of human parotid saliva by F. nucleatum was also inhibited by galactose and its structural analogs. Inhibition by lactose was 2 times that of galactose, inhibition by p-aminophenyl galactosides was 4 times that of galactose, and inhibition by asialoglycopeptides was 100 times that of galactose. Similar inhibition results were obtained for hemagglutination of neuraminidase-treated erythrocytes. These findings suggest that the binding specificity of F. nucleatum FN-2 is more complex than simply the recognition of the monosaccharide galactose. This is consistent with the concept that lectins considered identical in terms of monosaccharide specificity can recognize fine differences in more complex structures. To identify the specific bacterial component(s) involved in galactose recognition, proteins of F. nucleatum FN-2 were separated on a 4 to 11% gradient sodium dodecyl sulfate slab gel, transferred to nitrocellulose paper to renature bacterial binding sites, and then incubated with 125I-labeled asialofetuin. Autoradiographs of the nitrocellulose revealed a band at a range of Mr 300,000 to 330,000 which was not present when the blots were preincubated with galactose. These data support the concept that F. nucleatum FN-2 possesses a lectin that recognizes galactose and galactose-containing substrates.     

Precipitable immune complexes in healthy homosexual men, acquired immune deficiency syndrome and the related lymphadenopathy syndrome.

Increased levels of 3% PEG precipitable circulating immune complexes (CIC) were found in healthy homosexual men, in homosexual patients with the acquired immune deficiency syndrome (AIDS), and in the AIDS related lymphadenopathy syndrome (LAS). The degree of CIC elevation increases from healthy homosexual men to LAS and AIDS. Patients suffering from AIDS associated with opportunistic infections had a more pronounced increase in CIC than patients with AIDS associated Kaposi's sarcoma. In LAS and AIDS the amount of CIC correlated with the degree of inversion of the T4/T8 lymphocyte ratio, whereas in healthy homosexual men with increased levels of CIC the T4/T8 ratio was not significantly altered. Laser nephelometric partial components analysis revealed that these complexes were of a complement poor subtype with low component levels of C4, C1q and C3c. IgM and IgG were found to be the major components. It is suggested that these CIC might represent a marker of the total antigenic burden of the immune system. Possibly, they are of prognostic and monitoring value for clinical handling of patients at risk for AIDS.     

Genital herpesvirus hominis infection in mice. I. Development of an experimental model.

Pregnant female mice, after intravaginal inoculation with Herpesvirus hominis (HVH) type 2, developed vaginitis on days 5 to 7 after virus challenge, followed by hunching and hind limb paralysis on days 7 to 9 and death from encephalitis on days 9 to 11. After initial replication in the mucous membranes of the genital tract, virus spread to the spinal cord and ascended to involve the brain. Viremia or replication of H. hominis type 2 in the liver or spleen was not detected. Virus was cleared from vaginal secretions by days 8 to 10 after infection. Pregnant mice were more susceptible to the infection than nonpregnant mice. This experimental infection in female mice provides a model for genital herpesvirus infection and for herpesvirus infection and for herpesvirus encephalitis in which one can evaluate potentially promising antiviral chemotherapeutic agents.     

Studies on intracellular transport of secretory proteins in the rat exocrine pancreas

Summary The possible role of microtubules and microfilaments in the secretory process of the rat exocrine pancreas was analysed in vitro using isolated pancreatic lobules. Colchicine and vinblastine as microtubule inhibitors, hexylene glycol as a microtubule stabilizer, and cytochalasin B as a disruptive agent for microfilaments were used in increasing concentrations to test their effects on protein synthesis, intracellular transport, zymogen discharge, and cellular respiration.Colchicine only at 10^–2 M concentrations inhibits protein synthesis, while vinblastine inhibits at 10^–6 and 10^–5 M by 20% and at 10^–4 M by 55%. A similar inhibition is observed with 1.5% concentrations of hexylene glycol while cytochalasine B at 1,5 and 10 g/ml is without effect on protein synthesis. Colchicine and vinblastine have their major effects on intracellular transport both in secretion studies and cell fractionation experiments. Colchicine in concentrations between 10^–3 to 10^–5 M inhibits discharge of newly synthesized proteins by 50%, while vinblastine shows a dose-response relationship of 40% inhibition at 10^–6 M to 90% at 10^–4 M. Discharge of amylase is uniformly reduced by 30% by both colchicine and vinblastine in the whole dose range. The pronounced effect of colchicine and vinblastine is evident in cell fractionation studies: both drugs inhibit the disappearance of protein radioactivity from microsomes and its appearance in zymogen granules; similarly the peak radioactivity in smooth microsomes (Golgi) appears delayed. No differential effect on the secretory process was observed with 1.5% concentrations of hexylene glycol or cytochalasin B at 1.5 and 10 g/ml concentrations. A fines tructural analysis of microtubules and microfilaments in the exocrine pancreatic cell reveals their distribution in all parts of the cytoplasm and in relation to all cell organelles. Both systems (microtubules, microfilaments) seem to be connected, at least in certain areas of the cytoplasm and at the plasma membrane.The reduction of transport efficiency by microtubule inhibitors results in a deposition of secretory material in the cisternal space of the rough endoplasmatic reticulum, which leads to the formation of paracrystals. Colchicine at 10^–3 M concentrations leads to an enlargement of condensing vacuoles in the Golgi complex.A short communication on the same subject was presented at a Symposion on Stimulus-Secretion-Coupling in the Gastro-intestinal Tract, Titisee (May 27–29, 1975).Supported by Deutsche Forschungsgemeinschaft (Ke 113/8).     

Collagen and steroid hormones

The authors analyse the effects of steroid hormones on collagen, from up to date datas previously published and personal works. Glucocorticoids have catabolic effects; their molecular effects are reviewed. Conversely, oestrogens and androgens have an anabolic effect.     

Human acute pancreatitis: Its pathogenesis in the light of immunocytochemical and ultrastructural findings in acinar cells

Summary Human acute pancreatitis results from an autodigestive process frequently associated with alcohol abuse, gall stone disease and shock. Peripancreatic fat necrosis was identified as one of the earliest visible lesions, whereas acinar cell necrosis and haemorrhage were regarded as secondary changes. To examine the alterations in acinar cells in more detail, their enzyme content and fine structural features were studied immunocytochemically using antisera against -amylase, lipase, trypsin, chymotrypsin and pancreatic stone protein, and electronmicroscopically in pancreatic tissues from patients with severe acute pancreatitis. Peripheral acinar cells in the immediate vicinity of fat necrosis were found to be heavily degranulated, while acinar cells at some distance of necrosis fully retained their enzyme content. Other frequent changes of the acinar cells included cuboidal transformation, loss of microvilli, increased occurrence of autophagosomes, and formation of enlarged acinar lumina. As there was no apparent cell membrane leakage or rupture of duct lumina, it is concluded that the acinar cells adjacent to fat necrosis release their granules by undirected basolateral extrusion. The findings thus suggest that one of the basic defects in acute pancreatitis is the uncontrolled release of enzymes from peripheral acinar cells into the interstitial space which, in turn, presumably by the action of lipase, leads to autodigestive fat necrosis.Dedicated to Prof. Dr. G. Seifert on the occasion of his 65th birthdayPresented in part at the Second International Symposium on the Classification of Pancreatitis, Marseille, 1984, and at the Meeting of the European Pancreatic Club, Manchester, 1985     

Evaluation of nucleolus organizer regions (NORs) by automatic image analysis: a contribution to standardization.

This study summarizes our experiences with the silver staining of nucleolus organizer regions (AgNORs) in a total of 580 tumours from ten different tissues. In contrast to other investigators, we made use of automatic image analysis for the evaluation of AgNORs. This provided good reproducibility as determined by the standard cumulative means technique and intra-observer (r1) and inter-observer (r2) agreement in 30 benign (r1 = 0.83-0.95, r2 = 0.76-0.92) and 50 malignant tissue samples (r1 = 0.72-0.85, r2 = 0.51-0.78). By using a series of staining times on sections from 30 tissue blocks taken from the ten types of tissue investigated, considerable variation in the argyrophilic staining of NORs in different tissues and in different blocks from one tumour was shown. The mean AgNOR area of resting lymphocytes or connective tissue cells within tissue blocks of the same organ system varied up to four-fold, even though identical staining times had been used. The most suitable silver reaction time which rendered a good diagnostic difference in the AgNOR content of benign and malignant tissue ranged, for example, in the breast cancer specimens, from 23 to 35 min. We therefore conclude that the staining time has to be adjusted to the individual silver-binding characteristics of each tissue block or even each section. The use of internal staining standards like lymphocytes or connective tissue cells in the same tissue section is mandatory. This, in turn, is most precisely controlled by morphometry.     

Seroepidemiology of HTLV-III (LAV) in the Federal Republic of Germany

Summary In 1984 10,281 sera were collected in the FRG and examined for antibodies to HTLV-III (LAV) with an enzyme-linked immunosorbent assay and confirmative tests. Of the German AIDS patients 81% have antibodies. Individuals belonging to AIDS risk groups, homosexuals, haemophiliacs and i.v. drug abusers, have antibody frequencies between 25%–72%. The detection of HTLV-III antibodies in blood donours indicates that the virus is being transmitted by blood transfusions.Abbreviations AIDS acquired immunodeficiency syndrome - LAS lymphadenopathy syndrome - ARC AIDS related complex - LAV lymphadenopathy associated virus - HTLV-III human T-lymphotropic virus type III - HBV hepatitis B virus     

Experimental carotenoid retinopathy

beta-Carotene, canthaxanthin, and beta-carotene plus canthaxanthin were administered to "chinchilla bastard" pigmented rabbits in their rabbit diet (approximately 200 ppm carotenoid per group). The effect of the carotenoids on retinal function and morphology was tested against a control group in the course of 11 months. Electroretinography showed that in contrast to the control animals, beta-carotene-treated rabbits produced increasing peak latencies of the scotopic b-waves. In the canthaxanthin-treated rabbits, a- and b-waves showed hypernormal amplitudes at low cumulative dosages (approximately 0.5-2 g) and reduced amplitudes at higher dosages (about 5 g). The peak latencies of the scotopic a- and b-waves increased remarkably. This effect was still stronger in the carotenoid combination. Histology and electron microscopy indicated that in contrast to the control animals, canthaxanthin-treated rabbits showed a reduction in retinal thickness in some samples. In particular, they exhibited alterations in the granular layers and a marked diminuation of the photoreceptor outer segments and morphological alterations of the photoreceptor inner segments with massive deposition of electron-dense material. In all animals treated with carotenoids, lipid droplets of the retinal pigment epithelium were enlarged in size and number.