bluuebunny/crossref_metadata_2025 huggingface dataset:
A short exposure to a high‐glucose milieu stabilizes the acidic vacuolar apparatus of insulinoma cells in culture to ensuing oxidative stress
Authors: OLEJNICKA BEATA T. , ÖLLINGER KARIN , BRUNK ULF T.
Published: August 2009

It was recently suggested that extracellular hydrogen peroxide, after diffusing into and throughout adjacent cells ‐ which may be the case if they have only a weak capacity to degrade hydrogen peroxide ‐ labilizes their lysosomal compartment due to its content of low‐molecular‐weight iron in redox‐active form. The iron would be present as a consequence of normal autophagocytotic degradation of various iron‐containing metalloproteins. Beta‐ and insulinoma cells are especially vulnerable to oxidative stress, since they possess only low capacity to degrade hydrogen peroxide, and, perhaps, since they normally have a certain degree of autophagocytotic degradation of secretory granules with some iron content ‐ crinophagy. The toxicity to beta cells of oxidative stress, such as an exposure to alloxan, that results in extracellular formation of hydrogen peroxide, is considerably reduced if animals are initially given an intravenous bolus dose of glucose, temporarily bringing up the blood level to about 20 mM. In this study it was demonstrated that already as short an exposure as 30 min to 20 mM D‐glucose reduces the sensitivity of HIT and NIT insulinoma cells in culture to a subsequent exposure to hydrogen peroxide. In parallel, exposure to such a high‐glucose medium also reduces their desferrioxamine‐available amount of iron and, moreover, stabilizes their lysosomal membranes against oxidative stress ‐ thus preventing diffusion to the cytosol of damaging lysosomal contents following iron‐catalyzed, Fenton‐type, intralysosomal reactions. We suggest that both general autophagocytotic turnover and, in particular, crinophagy of secretory granules are decreased by an increased glucose concentration of the surrounding milieu, with attendant reduced amounts of intralysosomal low‐molecular‐weight iron and, thus, diminished sensitivity to oxidative stress.
Transduction potential of human retroviruses in highly proliferating small‐cell lung cancer cells as well as non‐proliferating hematopoietic stem cells
Authors: HANSEN JOHN‐ERIK S. , GRAM GREGERS J. , NIELSEN SUSANNE D. , SØRENSEN ANDERS , JENSEN PETER B. , SEHESTED MAXWELL , NIELSEN JENS O. , RØRTH MIKAEL
Published: August 2009

Direct gene transfer to solid tissues or metastatic cancer cells requires vectors capable of in vivo transduction to specific cells. The predominant retroviral vectors of murine origin are inactivated by human complement, which precludes their use in vivo. Such inactivation does not take place with vectors based on human retroviruses. Murine retroviral vectors are also limited to proliferating cells, which human retroviruses are not. In this study we examined whether or not a vector using components from the human retroviruses HIV‐1 and HTLV‐1 could infect small‐cell lung cancer cells and resting CD34+ hematopoietic stem cells. While HIV‐1 itself was unable to infect cells lacking the CD4‐membrane molecule, chimeric viral particles (pseudotype virus) with HIV‐1 genome and HTLV‐1 envelope components were able to infect both CD4‐containing lymphocytic cells, CD4‐negative tumour cells and hematopoietic stem cells. After infection with the pseudotype vector, the RNA genome was reverse transcribed and integrated. Transduction efficiency and gene expression under the HIV‐1 LTR promoter in both tumour and stem cells were found to be of a similar or greater magnitude than in lymphocytic cells. These results suggest that gene transfer targeting proliferating as well as resting cells in vivo may be realized using components from human retroviruses.
The histopathology of human gastric mucosa inhabited byHelicobacter heilmannii‐like (Gastrospirillum hominis) organisms, including the first culturable case
Authors: HOLCK SUSANNE , INGEHOLM PETER , BLOM JENS , NØRGAARD ANNETTE , ELSBORG LARS , ADAMSEN SVEN , ANDERSEN LEIF PERCIVAL
Published: August 2009

The aim was to determine the prevalence ofHelicobacter heilmannii‐like organisms in human gastric biopsies and the associated histology compared with that ofHelicobacter pylori‐bearing gastric biopsies. Furthermore, the feasibility of culturingH. heilmanniiwas examined. A consecutive series of 727 gastric biopsies from 650 patients were prospectively scrutinized forH. heilmannii. Their distribution pattern was recorded as well as the affiliated morphology of the gastric mucosa. Additional biopsies from some of the patients were examined microbiologically. Four cases (0.6%)(95% confidence intervals: 0.01–1.2%) of the examined material harbouredH. heilmannii. The bacterial burden was graded as sparse in three cases, moderate in one case. The distribution pattern was patchy; thus, in no case did all biopsies from one endoscopy compriseH. heilmannii. Adhesion to epithelial cells was infrequent. A mild gastritis, active in three cases, characterized all biopsies. Lymphoid aggregates occurred in biopsies from three patients. Micropapillary tufting of the epithelial layer and intestinal metaplasia were not apparent. Culture studies proved successful in the one of the four cases assayed. In conclusion the morphology ofH. heilmannii‐bearing mucosa deviates from that ofH. pylori‐associated mucosa by the absence of epithelial damage in the former. This observation can in part be explained by the predominant location ofH. heilmanniiat a distance from the epithelium in contrast to the conspicuousH. pyloriadhesion to epithelial cells, coupled with a usually low bacterial burden and patchy occurrence ofH. heilmanniias opposed to the generally more heavy infestation withH. pylori.
Chronic Pseudomonas aeruginosa lung infection is more severe in Th2 responding BALB/c mice compared to Th1 responding C3H/HeN mice
Authors: MOSER CLAUS , JOHANSEN HELLE KROGH , SONG ZHIJUN , HOUGEN HANS PETTER , RYGAARD JØRGEN , HØIBY NIELS
Published: August 2009

The chronic Pseudomonas aeruginosa lung infection in cystic fibrosis (CF) is characterized by a pronounced antibody response and microcolonies surrounded by numerous polymorphonuclear neutrophils (PMN). Poor prognosis is correlated with a high antibody response to P. aeruginosa antigens. An animal model of this infection was established in two strains of mice: C3H/HeN and BALB/c, generally known as Th1 and Th2 responders, respectively, which were challenged with alginate‐embedded P. aeruginosa. Mortality was significantly lower in C3H/HeN compared to BALB/c mice (p<0.025). P. aeruginosa was cleared more efficiently in C3H/HeN mice and significantly more C3H/HeN mice showed normal lung histopathology (p<0.02), and we found significantly fewer microabscesses in C3H/HeN mice than in BALB/c mice (p<0.005). In supernatants from P. aeruginosa antigen and concanavalin A‐stimulated spleen cells from the two strains of mice, the interferon‐ (IFN‐) γ levels were higher, whereas IL‐4 levels were lower in C3H/HeN mice than in BALB/c mice. The implications of these findings for CF patients with chronic P. aeruginosa lung infection are discussed.
Electron microscopic study of milk sediments
Authors: BURRIEL A. R. , BRENDLE J.
Published: August 2009

Sediment of milk from ovine mammary glands infected experimentally with coagulase‐negative staphylococci was examined by transmission electron microscopy. The proportions of the various particles and cells present in milk and of macrophages and neutrophils involved in phagocytosis were determined 6 h, 18 h and 49 days after infection. All cell types together predominated over cytoplasmic bodies in approximately 54% of normal milk samples. The proportion of macrophages in normal milk was higher than that of neutrophils in approximately 69% of samples examined. After infection and in the early phase of inflammation, the proportion changed in favour of neutrophils. In both the early and late phases of infection, greater numbers of macrophages (3–27.2%) than neutrophils (0–2.7%) contained phagocytized cocci. Moreover, greater numbers of cocci were observed in macrophages than in neutrophils (mean values 8.1 vs 1.2), indicating the importance of the macrophage in the maintenance of ovine subclinical mastitis caused by coagulase‐negative staphylococci.
Molecular pathology in the diagnosis of hematologic neoplasia
Authors: SAMBADE CLARA , SÄLLSTRÖM JAN F. , SUNDSTRÖM CHRISTER
Published: August 2009

Over the past decade molecular genetic methods have played an increasingly important role in the diagnosis of hematologic malignancies. Moreover, they have provided a tool to analyze many of the non‐random cytogenetic anomalies associated with hematologic neoplasias, contributing considerally to our understanding of several of those diseases, and to improving diagnostic accuracy. The rapid development of molecular genetics progressively allows the replacement of time‐consuming and technically demanding procedures. Even more relevant are the new clinical applications that already include the search for valuable prognostic information and ways of evaluating minimal residual disease or recognizing early relapsing disease. This paper is a critical but necessarily simplified overview of the main contributions of molecular genetics to the field of hematopathology. We discuss the information provided by several molecular methods within different clinical contexts, covering common problems in diagnostic pathology as well as prognostic evaluation and therapy monitoring.
Effect of NCAM‐transfection on growth and invasion of a human cancer cell line
Authors: EDVARDSEN KLAUS , BOCK ELISABETH , JIRUS STANA , FRANDSEN THOMAS LETH , HOLST‐HANSEN CLAUS , MOSER CLAUS , SPANG‐THOMSEN MOGENS , PEDERSEN NINA , WALSH FRANK S. , VINDELØV LARS L. , BRÜNNER NILS
Published: August 2009

A cDNA encoding the human transmembrane 140 kDa isoform of the neural cell adhesion molecule (NCAM) was transfected into the highly invasive MDA‐MB‐231 human breast cancer cell line. Transfectants with a homogeneous expression of NCAM showed a restricted capacity for penetration of an artificial basement membrane. However, when injected into nude mice, both control and NCAM‐expressing cell lines produced equally invasive tumors. Tumors generated from NCAM‐transfected cells were heterogeneous, containing NCAM‐positive as well as NCAM‐negative areas, indicating the existence of host factors capable of modulating NCAM expression in vivo. In nude mice, NCAM‐transfected cells developed tumors with longer latency periods and slower growth rates than tumors induced by NCAM‐negative control cells, implying that NCAM may be involved not only in adhesive and motile behavior of tumor cells but also in their growth regulation. There was no indication of differences in cell proliferative characteristics between the different NCAM‐transfected and the control transfected cells as determined by flow cytometric DNA analysis, suggesting an increased cell loss as the reason for decreased in vivo growth rate of the NCAM‐transfected cells. The fact that NCAM expression influences growth regulation attributes a pivotal role to this cell adhesion molecule during ontogenesis and tumor development.
Lack of active lung anaphylaxis in congenitally mast cell‐deficientWs/Wsrats sensitized with the nematodeNippostrongylus brasiliensis
Authors: NISHIDA MINORU , UCHIKAWA RYUICHI , TEGOSHI TATSUYA , YAMADA MINORU , MATSUDA SHINJI , SASABE MASATO , ARIZONO NAOKI
Published: August 2009

Ws/Wsrats are deficient in both mucosal‐ and connective tissue‐type mast cells. To study the role of mast cells in active anaphylaxis, changes in vascular permeability in the trachea upon intravenous antigen challenge with Evans blue dye were examined inWs/Ws, heterogenicWs/+, and normal +/+ rats sensitized with the nematodeNippostrongylus brasiliensis.Antigen challenge resulted in fatal anaphylactic shock in some +/+ andWs/+rats, but not inWs/Wsrats. Marked dye leakage developed within 30 min in the trachea of +/+ andWs/+rats, whileWs/Wsrats showed no substantial increases in the levels of vascular permeability.Ex vivostimulation of sensitized lung fragments from +/+ animals with specific antigen induced significant releases of histamine and leukotriene (LT) C4, while sensitizedWs/Wsrat‐lung fragments did not. InWs/Wsrats, levels of nematode‐specific IgE, IgG1 and IgG2a antibodies as well as levels of lung eosinophilia were not significantly different from those in +/+ rats. These results show that mast cell‐deficientWs/Wsrats fail to develop active anaphylaxis, and this is mediated probably by the lack of mast cell‐derived mediators required for initiation of the reaction.
Different ultrastructural morphology of Pneumocystis carinii derived from mice, rats, and rabbits
Authors: NIELSEN M. H. , SETTNES O. P. , ALIOUAT E. M. , CAILLIEZ J. C. , DEI‐CAS E.
Published: August 2009

Pneumocystis carinii (PC) is a fungus present in the lungs of many mammal species. Even though studies of the genome, the isoenzymes, and the antigens have proved some host‐species‐linked heterogeneity, the existence of distinct Pneumocystis species or subspecies has still not been accepted. Comparative studies of the ultrastructural morphology of pneumocysts derived from several host species may support evidence of host‐species‐linked heterogeneity. We have compared the ultrastructural morphology of pneumocysts derived from mice, rats, and rabbits. The density of membrane‐limited electron‐dense cytoplasmic granules was found to be higher in mouse‐derived pneumocysts than in rabbit‐derived pneumocysts, and furthermore the average diameter of the granules from mouse pneumocysts was larger than that of granules from rabbit‐derived pneumocysts. The average diameter of the filopodia of mouse‐derived pneumocysts was smaller than that of filopodia from rat‐derived pneumocysts, which was smaller than that of filopodia from rabbit‐derived pneumocysts. Globular electron‐dense bulbous dilatations at the tip of the filopodia were described for the first time and they were only found on filopodia of mouse‐derived pneumocysts. These distinct host‐species‐linked morphological differences of pneumocysts from mouse, rat, and rabbit may support previous biochemical data indicating the existence of different Pneumocystis species or subspecies.
Antibody responses in serum and lung to intranasal immunization with Haemophilus influenzae type b polysaccharide conjugated to cholera toxin B subunit and tetanus toxoid
Authors: BERGQUIST CHARLOTTA , LAGERGÅRD TERESA , HOLMGREN JAN
Published: August 2009

Aim: Cholera toxin B subunit (CTB) has previously been used as a mucosal carrier for various vaccine candidate antigens. The objective of this study was to see if coupling a bacterial polysaccharide, Haemophilus influenzae type b capsular polysaccharide (HibCPS), to CTB, either directly or through prior coupling to tetanus toxoid (TT), would improve the immunogenicity of HibCPS after nasal immunization. Methods: HibCPS was conjugated to CTB, TT or via TT to CTB, using glutaraldehyde or 1‐ethyl‐3(3‐dimethylaminopropyl)‐carbodiimide (EDAC) and N‐succinimidyl 3‐(2‐pyridyldithio) propionate (SPDP). The conjugates were characterized and used for intranasal (IN) and subcutaneous (SC) immunizations of mice. The anti‐Hib, ‐TT and ‐CTB antibody titers in serum and lungs after the immunizations were measured with ELISA. Results: The HibCTB was poorly immunogenic both given IN and SC compared with HibTT and HibTTCTB, probably because of inefficient coupling. In contrast, the conjugation of CTB to the HibTT conjugate resulted in a preparation which was superior both to the HibTT and the HibCTB conjugates in inducing local IgA and IgG anti‐HibCPS antibodies in the lungs. The anti‐HibCPS serum IgG titers after IN immunization with the HibTTCTB conjugate were similar to the titers after IN immunization with HibTT, or SC immunization with a commercial HibCRM conjugate vaccine. In contrast to the other conjugates, the HibTTCTB conjugate also gave rise to anti‐Hib serum IgA titers. Conclusion: We conclude that appropriate conjugation to CTB increases the mucosal immunogenicity of HibCPS, and that intranasal immunization with such a conjugate can give rise to both local and systemic anti‐HibCPS antibody responses.
Neuroendocrine differentiation and nerves in human adrenal cortex and cortical lesions
Authors: LI QING , JOHANSSON HENRY , KJELLMAN MAGNUS , GRIMELIUS LARS
Published: August 2009

Neuroendocrine differentiation and nerve distribution were studied in sections from human cortex (n=11) and cortical lesions (hyperplasias, n=9; adenomas, n=13; carcinomas, n=14) with four markers, namely chromogranin A(CgA), synaptophysin (SYN), neuron‐specific enolase (NSE), protein gene product (PGP) 9.5 and small synaptic vesicle protein (SV)2. All but two cases expressed neuroendocrine differentiation. NSE was the most commonly occurring marker and the NSE immunoreactive cells were detected in normal cortex, mainly in zona glomerulosa, as well as in adenomas and carcinomas. SYN and PGP 9.5 immunoreactive cells were especially prominent in the carcinomas, while SV2 immunoreactive cells were seen mainly in normal cortex. The difference in distribution pattern of the neuroendocrine markers between adenomas and carcinomas was not so distinct that it can be used for histopathological diagnosis. The significance of neuroendocrine differentiation in cortex and cortical lesions is uncertain, but may reflect an involvement in special hormonal functions. No obvious relationship was found between the clinical syndromes and the degree of neuroendocrine differentiation. Three of the neuroendocrine markers also visualized nerve structures. PGP 9.5, which is regarded as the most ‘general’ nerve marker, visualized more nerve structures than did the other markers. Normal cortex contained most immunoreactive nerves, whereas they were less numerous in hyperplasias and sparse or even absent in the neoplasms. The nerves appeared among the parenchymal cells but were particularly prominent around vessels. The results suggest that the cortical nerves influence not only the regulation of the blood supply but also the hormonal regulation at the cellular level.
Iron and LDL‐oxidation in atherogenesis.
Authors: YUAN X. M. , BRUNK U. T.
Published: August 2009

It has been proposed that the development of atherosclerosis may be linked to the size of the body iron stores. The exact role of iron in the initiation and progression of atherogenesis is, however, still unknown. As a result of increasing support for the LDL‐oxidation hypothesis, much additional knowledge about the relation between iron and atherosclerosis has recently been gained. This review presents the current evidence on the role of iron – being a potent catalyst of oxidative reactions – and macrophage‐mediated LDL‐oxidation in atherogenesis. The authors hypothesize that iron, as a possible central intermediary, may play an important role in cell‐mediated LDL‐oxidation.
Effects of β2 adrenoceptor agonists on T‐cell subpopulations
Authors: HOLEN E. , ELSAYED S.
Published: August 2009

The aim of the present communication is to determine the effects of β2 adrenoceptor agonists on growth and cytokine secretion using allergen‐specific T cells. Four β2 adrenoceptor agonists were administered at therapeutically relevant doses (salbutamol 1–2 μM; salmeterol 0.03–0.06 μM; terbutaline 0. 56–1.12 μM, and fenoterol 0.7–1.4 μM to: a) Cultures of human peripheral mononuclear cells (PBMC) b) Positively selected CD4+ and CD8+ subsets, c) Allergen‐specific T‐cell lines (TCL). Drug effects on growth kinetics and the secretion of IL‐4, IL‐5, INF‐γ and IgE following T‐cell stimulation were investigated. Comparing the growth inhibitory effect of the 4 β2 agonists at 2 different concentrations, using 12 PBMC, 10 CD4+ and CD8+ and 10 TCL cultures, the following patterns were observed: PBMC‐, CD4+‐ and CD8+ ‐cultures: salmeterol, followed by salbutamol and fenoterol, was a more potent inhibitor than terbutaline. In long‐term TCL‐cultures, salmeterol was the most potent drug, followed by fenoterol. No significant differences were observed between salbutamol and terbutaline. TCL secretion of IL‐4 and IL‐5 (TH2 cytokines) was also significantly inhibited. In one patient, INF‐γ secretion (TH1/THO cytokine) could be enhanced by drug administration. High IgE secretion, from 1% remaining B cells in one of the patients, following PHA+IL‐2 stimulation, could be reduced by the drugs. The results showed that the β2 agonists could influence T‐cell growth and function. The changes regarding cell function were individual and related to T‐cell phenotypes secreting TH1/THO or TH2 cytokines. These results suggest that administration of β2 adrenoceptor agonists could be beneficial, not only for bronchodilation, but also for suppressing the underlying inflammatory process dominated by TH2‐like cytokine secretion.
Intra‐ and interstrain differences of virulence among nontypeable Haemophilus influenzae strains
Authors: MELHUS ÅSA , HERMANSSON ANN , FORSGREN ARNE , PRELLNER KARIN
Published: August 2009

Nontypeable Haemophilus influenzae (NTHi) is sometimes the causative agent of invasive diseases, and it has been suggested that there may be differences in virulence among NTHi strains. Whilst studying clinical isolates of NTHi in a rat model of acute otitis media, intra‐ and interstrain differences in virulence were observed. Two strains with suddenly reduced capacity to cause middle ear infections and one highly virulent strain with dose requirements comparable only to encapsulated H. influenzae strains were further investigated, together with 15 other H. influenzae strains. The strains were characterized by analyzing the lipopolysaccharide, the outer membrane proteins, the hemagglutinating ability, and the polymerase chain reaction products after amplification of a gene sequence associated with encapsulation. The pathogenic capacity was assessed in two different in vivo models. It was found that the two strains with reduced pathogenic capacity could regain their virulence after animal passage. The LPS analysis and the results from the chicken embryo model suggested that the observed change in virulence might be associated with the lipopolysaccharide. For the non‐animal‐passaged strain 3655 there were indications that an undefined factor(s) contributed to its relatively potent virulence. As all three strains lacked genes necessary for encapsulation, in no case could any part of the increased virulence be attributed to the expression of small amounts of capsule.
The complement regulatory proteins CD46 and CD59, but not CD55, are highly expressed by glandular epithelium of human breast and colorectal tumour tissues
Authors: THORSTEINSSON L. , O'DOWD G. M. , HARRINGTON P. M. , JOHNSON P. M.
Published: August 2009

Three of the proteins protecting cells from autologous lysis by complement are: membrane cofactor protein (MCP; CD46), an inhibitor of the membrane attack complex formation (CD59), and decay accelerating factor (DAF; CD55). We have investigated the expression of these proteins in breast and colorectal carcinoma by immunohistochemistry and immunoblotting of breast tissue for CD46. CD46 was consistently and strongly expressed in the epithelial compartment in 26/28 ductal carcinomas of the breast, 9/9 fibroadenomas, and 9/11 cases of control non‐neoplastic breast tissue. CD59 showed a similar degree of expression in the fibroadenomas (9/9), but was less strongly expressed in carcinomatous (22/28) and control (5/11) tissues. In marked contrast, no CD55 expression was detected in tissue from 15 ductal carcinomas. Immunoblotting of breast tissue for CD46 showed the same size of the molecule as for lymphocytes. It had however considerably stronger expression in tumour tissue than in non‐neoplastic tissue. CD46 and CD59 were either lacking or only weakly expressed in the epithelial component of control colorectal mucosa: 2/15 and 5/15, respectively. In contrast, tissue samples from colorectal adenocarcinomas showed clear staining for both CD59 (10/18) and, more markedly, CD46 (15/18). There was no association between the pattern or intensity of CD46 and CD59 expression and tumour differentiation. As the complement regulatory proteins CD46 and CD59 are also strongly expressed by trophoblast at the feto‐maternal tissue interface, these results support the concept that similar mechanisms are employed both by the genetically dissimilar fetus and certain tumours to evade immune attack by their host.
Antimicrobial susceptibilities and beta‐lactamase production of Shigella isolates in Crete, Greece, during the period 1991–1995
Authors: MARAKI S. , GEORGILADAKIS A. , CHRISTIDOU A. , SCOULICA E. , TSELENTIS Y.
Published: August 2009

The susceptibility to 11 antibiotics was determined for 52 strains of Shigella isolated from patients with diarrheal disease in Crete, Greece, during the period 1991–1995. Forty‐six percent of the isolates were resistant to ampicillin, 48% to tetracycline, 44.2% to chloramphenicol, and 28.8% to cotrimoxazole. Shigella flexneri was more resistant than S. sonnei to ampicillin (82 vs 4.3%), to tetracycline (82 vs 8.7%) and to cotrimoxazole (42.8 vs 13%). Overall, 82% of all S. flexneri isolates were resistant to the three or four antimicrobial agents tested. The β‐lactamases produced by shigellae were identified by isoelectric focusing and were found to be OXA‐1, TEM‐1, and a low‐level β‐lactamase with a pI>8. The results from the present study, which is the first carried out in Crete, emphasize the need for continuous surveillance of resistance and control of antibiotic usage.
Serological analysis of C‐terminal region of α antigen from Mycobacterium avium‐intracellulare complex and Mycobacterium tuberculosis
Authors: KITAURA HIDEKI , OHARA NAOYA , NAITO MARIKO , KOBAYASHI KAZUHIDE , YAMADA TAKESHI
Published: August 2009

The α antigen, which is a 30 kDa protein secreted by mycobacterial species, is an immunodominant antigen. The C‐terminal regions of α antigens are highly divergent, though there are regions where the amino acid sequence of α antigen is conserved. We investigated whether the C‐terminal regions of the Mycobacterium aviumα antigen, M. intracellulareα antigen and M. tuberculosisα antigen contain sequence‐specific B‐cell epitopes. The C‐terminal regions of M. aviumα antigen and M. intracellularα antigen reacted to anti‐M. aviumα antigen but not to anti‐M. tuberculosisα antigen derived from rabbits. Thus, M. avium and M. intracellulare have an antigenic determinant in common with rabbit. The C‐terminal region of M. tuberculosisα antigen did not react to anti‐M. aviumα antigen or anti‐M. tuberculosisα antigen. An enzyme‐linked immunosorbent assay revealed that only the C‐terminal region of M. aviumα antigen reacted to the sera of two of six patients with M. avium‐intracellulare (MAC) but not to the sera of patients with M. tuberculosis. In contrast, the C‐terminal regions of M. intracellulareα antigen and M. tuberculosisα antigen were not recognized by the sera from patients with MAC or M. tuberculosis. This region of M. aviumα antigen can produce a sequence‐specific B‐cell epitope in humans.
Interstitial cystitis
Authors: HORN THOMAS , HOLM NINA RAAE , HALD TAGE
Published: August 2009

Ultrastructural investigation of detrusor muscle cells in biopsies from 13 patients (8 interstitial cystitis (IC) and 5 controls) was performed. In all IC‐patients and in one control a varying number of smooth muscle cells revealed a characteristic oak leaf pattern with protrusions of the sarcolemma. The alterations may express degeneration of smooth muscle cells. Although most probably non‐specific yet highly characteristic, the ultrastructural detrusor changes may be important in diagnosing IC.
Borrelial lymphocytoma – a historical case
Authors: SONCK C. E. , VILJANEN M. , HIRSIMÄKI P. , SÖDERSTRÖM K. O. , EKFORS T. O.
Published: August 2009

We here describe a patient with a tick bite in the areola mammae in 1953 followed by erythema migrans. Twenty years later, after another tick bite in the axillary skin, also followed by erythema migrans, a large lymphatic infiltrate developed in the mammary skin, when the margin of the erythema reached the areola. The infiltrate resolved within a year without any therapy. Borrelial DNA was detected by polymerase chain reaction in the paraffin blocks of the lymphatic skin infiltrate. The patient died 9 years later of generalized lymphoma. A similar monoclonal immunoglobulin heavy chain gene rearrangement was detected both in the mammary skin lesion and in the lymphoma specimen.
Expression of keratin 13, 14 and 19 in oral squamous cell carcinomas from Sudanese snuff dippers: Lack of association with human papillomavirus infection
Authors: IBRAHIM SALAH O. , BERTELSEN BJØRN , KALVENES MAY BRITT , IDRIS ALI M. , VASSTRAND ENDRE N. , NILSEN RUNE , JOHANNESSEN ANNE C.
Published: August 2009

In stratified squamous epithelia, altered expression of keratins (Ks) is one possible marker of malignant potential. In the epithelium of the uterine cervix, presence of human papillomaviruses (HPVs) is increasingly regarded as a marker of risk for cervical cancer. However, a similar role in oral cancer and precancer remains controversial. To address these questions, formalin‐fixed, paraffin‐embedded oral carcinomas from Sudanese snuff dippers (n=14) and oral carcinomas from Sudanese (n=14), Swedish (n=19) and Norwegian (n=41) non‐snuff dippers were examined by immunohistochemistry for expression of K types 13, 14 and 19 using monoclonal antibodies. HPV infection was searched for in all the carcinomas by in situ hybridization (ISH) using the cocktail HPV OmniProbe and the ViraType probe. Carcinomas from Sudanese (snuff dippers/non‐snuff dippers) were also examined for HPV infection by polymerase chain reaction (PCR) using the general HPV primers GP5+/GP6+. For the oral carcinomas from snuff dippers, moderate to intense expression of K13 (71%; 10/14), K14 (86%; 12/14) and K19 (93%; 13/14) was found. For the oral carcinomas from non‐snuff dippers, weak to moderate expression of K13 (64%; 47/74), K14 (43%; 32/74) and K19 (45%; 33/74) was found. HPV DNA was not detected in any of the carcinomas from three countries when examined by ISH. The Sudanese (from snuff dippers/non‐snuff dippers) oral carcinomas were also negative for HPV DNA with the PCR. The present study shows that (i) there is a high level of expression of K13, K14 and K19 in oral carcinomas from snuff dippers compared to those from non‐snuff dippers, (ii) this high level of expression may arise from dysregulation of keratinocyte proliferation and maturation caused by damaging effects of snuff, (iii) the HPV genome is not found in Sudanese (snuff dippers/non‐snuff dippers), Swedish or Norwegian oral carcinomas, and (iv) this may suggest that these viruses do not play a prominent role in the aetiology of oral carcinomas from these countries.
Does smoking stimulate rheumatoid factor production in non‐rheumatic individuals?
Authors: JÓNSSON THORBJÖRN , THORSTEINSSON JÓN , VALDIMARSSON HELGI
Published: August 2009

Smoking has been associated with increased incidence of rheumatoid arthritis (RA), joint damage and positive rheumatoid factor (RF). Here we report an analysis of the association between smoking and IgM, IgG and IgA RF in a cohort of non‐rheumatic individuals participating in a prospective longitudinal study of the incidence and significance of elevated RF. From the initial cohort of nearly 14,000 randomly selected individuals aged 52–80 years, 109 RF‐positive and 187 RF‐negative non‐rheumatic participants were recruited. All participants were tested for RF at least twice at an interval ranging from 4 to 13 years. Of the RF‐negative participants 21.9% were active smokers compared to 34.1% of IgM RF‐positive (p=0.035), 20.8% of IgG RF‐positive (N.S.) and 34.4% of IgA RF‐positive participants (p=0.047). Smoking was most prevalent (44.8%) amongst participants with elevation of both IgM and IgA RF (p=0.008), and smokers were also significantly more likely to have a persistent elevation of RF than non‐smokers (p=0.024). These findings indicate that smoking may influence the immune system, leading to increased production of IgM and IgA RF.
Detection of extended‐spectrum β‐lactamases
Authors: SCHUMACHER H. , BENGTSSON B. , BJERREGAARD‐ANDERSEN H. , JENSEN T. G.
Published: August 2009

The susceptibility testing methods used in Denmark were evaluated with respect to their ability to detect cephalosporin resistance with cefuroxime as indicator, especially resistance caused by extended‐spectrum β‐lactamases (ESBLs). Two methods for determination of minimal inhibitory concentration (MIC), three agar diffusion methods, a disc approximation test and the ESBL‐Etest were used against a panel of strains producing well‐known β‐lactamases. The tablet diffusion test (Rosco Neo Sensitabs) as the most used in Denmark had the lowest detection rate of cefuroxime resistance among ESBL‐producing strains. The prediffusion method, which is only used at one laboratory, was the most reliable method for such detection. The MIC methods were in good agreement, but the detection rate for resistance due to ESBLs was low and depended on the antibiotics used. The disc approximation test and the ESBL‐Etest both resulted in an acceptable ESBL detection rate. The latter tests discriminated between isolates producing the frequent chromosome‐mediated and the in Denmark probably very rare ESBL‐mediated cephalosporin resistance. For the evaluation of susceptibility tests such strains require special attention.
Reduced pathogenicity of a Candida albicans MAP kinase phosphatase (CPP1) mutant in the murine mastitis model
Authors: GUHAD FAISAL A. , CSANK CSILLA , JENSEN HENRIK E. , THOMAS DAVID Y. , WHITEWAY MALCOLM , HAU JANN
Published: August 2009

Candida albicans strains with a deletion of the mitogen‐activated protein kinase tyrosine phosphatase gene (CPP1) are derepressed in the yeast‐to‐hyphal transition on solid surfaces in vitro at ambient temperatures and this gene is therefore required for repression of the yeast‐to‐hyphal switch. The pathology caused by a CPP1 null mutant strain was compared with that of the null mutant into which the wild‐type CPP1 gene was introduced by homologous recombination and with the wild‐type parent strain in a murine mycotic mastitis model. The mammary glands of lactating mice (at day 5 postpartum) were infected for 2, 4 and 6 days with 1 times 105, 1 times 106 and 1 times 107 cell‐forming units before euthanasia. Infected and non‐infected control glands were evaluated histopathologically. The null mutant strains showed less severe pathology than the two control strains. The Cpp1p tyrosine phosphatase may thus be considered a virulence determinant during localized infection in C. albicans.
High MHC class I expression correlates with slow growth in UV‐induced skin carcinomas in hairless mice
Authors: SVANE INGE MARIE , ENGEL ANNE‐MARIE , THOMSEN NIELS BECH , WULF HANS CHRISTIAN , WERDELIN OLE
Published: August 2009

An experiment was set up to investigate the relationship, if any, between cell surface MHC class I expression and the growth rate for skin tumors induced by two different UV radiation regimens in hairless mice. Two groups of 20 hairless mice were each irradiated with either a UVA radiation source (2 SED per session) or broad‐spectrum UV radiation (UVB) (8.1 SED per session) 5 days a week during the entire experiment. In the UVA group, 17 out of 20 animals developed tumors, and 10 of these grew to a diameter of ≥5 mm. In the UVB group, 19 out of 20 animals developed tumors, and 15 of these grew to a diameter of ≥5 mm. The tumor induction time, i.e. the time from the start of UV treatment to tumor appearance, was found to be significantly longer (p<0.01) in the UVA than in the UVB group. This is in accordance with previous findings. Of the 25 tumors growing to a diameter of ≥5 mm, 11 were established as cultured cell lines (4 UVA and 7 UVB tumors). These uncloned cell lines were analyzed for surface expression of major histocompatibility complex class I by FACS analysis. There was a clear correlation between high MHC class I expression and slow growth of the individual tumors (p<0.05). This suggests a role for the MHC class I governed, i.e. cytotoxic T‐cell‐mediated, reactions in deciding the fate of UV‐induced skin cancers. No correlation was found between MHC class I expression and tumor induction time.
The in vivo and in vitro effects of rhG‐CSF on allergic, haematological and biochemical variables
Authors: KRISTENSEN K. S. , PEDERSEN M. , CLEMENTSEN P. , OLSEN O. T. , SKOV P. S. , PERMIN H. , NORN S.
Published: August 2009

The objective was to evaluate the influence of treatment with rhG‐CSF on allergic indexes. This was done by open trial of 5 days' treatment with rhG‐CSF (5 μg/kg/day s. c.). 10 patients (6 men), aged 28 to 54 years, with rhinoconjunctivitis due to grass pollen allergy, participated in the investigation. Main measures were blood count, basophil histamine release, skin test and conjunctival provocation test. Results: The treatment resulted in significant increases in numbers of neutrophils (590%), basophils (280%), eosinophils (250%) and lymphocytes (71%). Total blood histamine was increased, but basophil histamine releasability was decreased. Serum alkaline phosphatase increased 92% and serum lactate dehydrogenase increased 35% (both significant). There were no significant changes in the skin tests and the conjunctival provocation tests. Two months after the treatment all tests had returned to baseline levels. Five of the patients (50%) reported side effects, one withdrew. In conclusion treatment with rhG‐CSF increases the number of circulating blood cells other than neutrophils without causing changes in indexes of allergic reactivity.
Secretion of IL‐6, IL‐8 and G‐CSF by human endothelial cells in vitro in response to Staphylococcus aureus and staphylococcal exotoxins
Authors: SÖDERQUIST BO , KÄLLMAN JAN , HOLMBERG HANS , VIKERFORS TOMAS , KIHLSTRÖM ERIK
Published: August 2009

The capacity of endothelial cells to produce and release cytokines (IL‐6, IL‐8 and G‐CSF) in response to exposure to Staphylococcus aureus strains or staphylococcal exotoxins (α‐toxin, enterotoxin A and TSST‐1) was investigated. An endothelial cell culture model of human umbilical vein endothelial cells (HUVEC) was used. Five out of ten clinical isolates of S. aureus were found to induce cytokine production and release from endothelial cells. Four of the five isolates that induce cytokine release produced enterotoxin A, B, C, D and/or TSST‐1, compared with two of those that did not induce release. Purified staphylococcal exotoxins (1 pg/ml – 1 μg/ml) did not act as primary stimuli and induced no detectable cytokine secretion. When endothelial cells were prestimulated with IL‐1β or TNFα at a concentration of 1 ng/ml for 2 h, IL‐1β served as a potent primary stimulus for IL‐6, IL‐8 and G‐CSF production, whereas TNFα did not induce any significant cytokine release during the subsequent 24 h. A further increase in IL‐6 and G‐CSF release, but not of IL‐8, was observed when IL‐1β prestimulated cells were exposed to α‐toxin or TSST‐1. However, to potentiate cytokine production (IL‐6 and IL‐8) by SEA, both IL‐1β and the toxin had to be present simultaneously. Our data show that S. aureus, but not staphylococcal exotoxins, have the capacity to act as primary stimuli of endothelial cells and induce production and release of cytokines. IL‐1β may prime HUVEC to release IL‐6, IL‐8 and G‐CSF prior to subsequent stimulation with staphylococcal exotoxins.
Herpes simplex virus type 1 inhibits in vitro differentiation and selected functions of human blood‐derived monocytes
Authors: BRUUN T. , KRISTOFFERSEN A. K. , ROLLAG H. , BECK S. , DEGRÉ M.
Published: August 2009

We have studied the effect of herpes simplex virus type 1 (HSV1) infection on in vitro differentiation of blood‐derived human monocytes into macrophages using morphological, functional and biochemical parameters that alter during macrophage differentiation. Purified preparations of HSV modified the monocyte‐macrophage differentiation, in spite of the fact that the virus did not replicate in monocytes. Disappearance of expression of a monocyte‐specific surface antigen and the typical development of morphological appearance were delayed in HSV‐ infected cells. Production of the lysosomal enzyme acid phosphatase, which normally increases during differentiation, was also reduced in infected cells. Transcription of the oncogenes c‐myc and c‐fos, and the Hsp70 gene was modified in cells from some donors but not in other cell preparations. Possible mechanisms of these effects are discussed.
Germ cell cancer and disorders of spermatogenesis: An environmental connection?
Authors: SKAKKEBÉK NIELS E. , MEYTS EWA RAJPERT‐DE , JØRGENSEN NIELS , CARLSEN ELISABETH , PETERSEN PETER MEIDAHL , GIWERCMAN ALEKSANDER , ANDERSEN ANNE‐GRETHE , JENSEN TINA KOLD , ANDERSSON ANNA‐MARIA , MÜLLER JØRN
Published: August 2009

Why is there a small peak of germ cell tumours in the postnatal period and a major peak in young age, starting at puberty? And, paradoxically, small risk in old age, although spermatogenesis is a lifelong process? Why is this type of cancer more common in individuals with maldeveloped gonads, including undescended testis, gonadal dysgenesis and androgen insensitivity syndrome? Why has there, during the past 50 years, been a quite dramatic increase in testicular cancer in many developed countries? These are just a few of many questions concerning testicular cancer. However, the recent progress in research in the early stages of testicular cancer (carcinoma in situ testis (CIS)) allows us to begin to answer some of these questions. There is more and more evidence that the CIS cell is a gonocyte with stem cell potential, which explains why an adult man can develop a non‐seminoma, which is a neoplastic caricature of embryonic growth. We consider the possibility that CIS cells may loose their stem cell potential with ageing. Along these lines, a seminoma is regarded a gonocytoma where the single gonocytes have little or no stem cell potential. The Sertoli and Leydig cells, which are activated postnatally and during and after puberty, may play a crucial role for both the development of the CIS gonocyte and progression of the neoplasm to invasiveness. The reported increase in testicular cancer is not the only sign that male reproductive health is at risk. There are reports that undescended testis and hypospadias have become more common. Also semen quality has deteriorated, at least in some countries. The epidemiological evidence suggests that environmental factors may play a role. Are the environmental hormone disrupters (e.g. DDT, PCB, nonylphenol, bisphenol A) to be blamed for the apparently synchronised deterioration in these aspects of male reproductive health?
Spermatogonial transplantation and reconstitution of donor cell spermatogenesis in recipient mice
Authors: NAGANO M. , BRINSTER R. L.
Published: August 2009

Recently, we described a method to transplant testicular cells from a fertile donor mouse to the seminiferous tubules of an infertile recipient male, where the donor cells generate spermatogenesis. Spermatozoa produced by the transplanted cells in the recipient testis will fertilize eggs and transmit the donor haplotype to the resulting animals. In the most successful transplantations, up to 80 per cent of progeny sired by the recipient male arise from donor cell‐derived spermatozoa. The cell responsible for generation of spermatogenesis following transplantation clearly is a spermatogonial stem cell, since the repopulation of recipient testes extends for periods exceeding 12 months. In the past year, experiments have shown that rat testicular cells transplanted to the seminiferous tubules of immunodeficient mice will generate rat spermatogenesis and produce normal appearing rat spermatozoa, opening the possibility of xenogeneic testicular cell transplantation for other species. In addition, it has proved possible to cryopreserve spermatogonial stem cells for long periods, following which they will produce normal spermatogenesis when transplanted to a recipient. The ability to cryopreserve testicular stem cells makes individual male germ lines immortal. In current work, we are focusing on techniques to increase the efficiency of spermatogonial transplantation and methods to culture the stem cells.
Primordial germ cells, stem cells and testicular cancer
Authors: DONOVAN PETER J. , DE MIGUEL MARIA , CHENG LINZHAO , RESNICK JAMES L.
Published: August 2009

Primordial Germ Cells (PGCs) arise in the mouse embryo as a small population of cells some way from the gonad anlagen. In order for the embryo to develop into a fully fertile adult animal the PGCs must increase in number and reach the gonad. Mutations causing sterility in the mouse have identified some of the genes involved in regulating PGC development and some of these genes have been molecularly cloned. Similarly, mutations affecting the development and differentiation of PGC‐derived tumors (teratomas and teratocarcinomas) have been identified in certain strains of mice and these identify genes involved in the normal growth and differentiation of PGCs. These studies should help to define the role of growth factors in PGC development and in the development of germ‐cell‐derived tumors.
Teratocarcinomas and human embryology: Pluripotent human EC cell lines
Authors: ANDREWS PETER W.
Published: August 2009

The histogenesis of germ cell tumours (GCT) reflects the normal processes of gametogenesis, fertilisation and subsequent embryonic cell differentiation. Understanding the mechanisms that control the differentitation of embryonal carcinoma (EC) cells into a variety of embryonic and extraembryonic cell types is pertinent to understanding the progression of GCT. EC cells also provide a tool for analysing the mechanisms that control differentiation during embryonic development, and particularly the mechanisms that control differentiation along alternative cell line, NTERA2, into neurones and other cell types in response to agents such as retinoic acid, HMBA and the bone morphogenetic proteins. We have also compared the pluripotent NTERA2 EC cells with other human EC cell lines that exhibit a much reduced capacity for cell differentiation. A variety of genes are activated during NTERA2 differentiation. In particular we have identified a novel human member of the wnt family. This wnt gene is activated following retinoic acid induction of differentiation but is later down‐regulated as the cells mature into neurones and other cell types. We have also observed expression of genes belonging to the Frizzled family, which is likely to include genes encoding receptors for the wnt gene products. Thus in the NTERA2 system, genes pertinent to regulating cell differentiation during embryonic development are activated and appear to play a role in modulating how these pluripotent human EC cells differentiate.