bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular regulation, membrane association and secretion of tumor cathepsin B
Authors: FROSCH BARBARA A. , BERQUIN ISABELLE , EMMERT‐BUCK MICHAEL R. , MOIN KAMIAR , SLOANE BONNIE F.
Published: August 2009

Upregulation, membrane association and secretion of cathepsin B have been shown to occur in many types of tumors and to correlate positively with their invasive and metastatic capabilities. To further understand changes in cathepsin B activity and localization, we have been examining its regulation at many levels including transcription and trafficking. Our studies indicate that there may be three promoter regions in the cathepsin B gene. Of these, continued examination of the promoter upstream of exon I has indicated possible control by several regulatory factors including E‐box and Sp‐1 binding elements. Upregulation of cathepsin B at this level may account for some of the secretion of cathepsin B found in tumors. We have also gathered evidence that endo‐and exocytosis of cathepsin B may be regulated by ras and ras‐related proteins in addition to previously described trafficking systems. There is also evidence that several populations of lysosomes may exist and that trafficking to different populations may determine whether cathepsin B is secreted from the tumor cell or remains intracellular. Our results indicate that membrane association and secretion of cathepsin B is not a random process in the tumor cell, but rather part of a tightly controlled system.
Mechanisms for pro matrix metalloproteinase activation
Authors: MURPHY GILLIAN , STANTON HEATHER , COWELL SUSAN , BUTLER GEORGINA , KNÄUPER VERA , ATKINSON SUSAN , GAVRILOVIC JELENA
Published: August 2009

The activation of pro matrix metalloproteinases (MMPs) by sequential proteolysis of the propeptide blocking the active site cleft is regarded as one of the key levels of regulation of these proteinases. Potential physiological mechanisms including cell‐associated plasmin generation by urokinase‐like plasminogen activator, or the action of cell surface MT1‐MMPs appear to be involved in the initiation of cascades of pro MMP activation. Gelatinase A, collagenase 3 and gelatinase B may be activated by MT‐MMP based mechanisms, as evidenced by both biochemical and cell based studies. Hence the regulation of MT‐MMPs themselves becomes critical to the determination of MMP activity. This includes activation, assembly at the cell surfaces as TIMP‐2 complexes and subsequent inactivation by proteolysis or TIMP inhibition.
Expression and regulation of collagenase‐3 (MMP‐13) in human malignant tumors
Authors: BALBÍN MILAGROS , PENDÁS ALBERTO M. , URÍA JOSÉ A. , JIMÉNEZ MARIA G. , FREIJE JOSÉ P. , LÓPEZ‐OTÍN CARLOS
Published: August 2009

Human collagenase‐3 (MMP‐13) is a matrix metalloproteinase originally identified in breast carcinomas. Recent studies have revealed that this enzyme is also produced by a variety of malignant tumors including head and neck carcinomas, chondrosarcomas and basal cell carcinomas of the skin. In all cases, the expression of collagenase‐3 is associated with aggressive tumors. Different cytokines, growth factors and tumor promoters are able to up‐regulate collagenase‐3 expression in tumor cells or in stromal cells surrounding epithelial tumor cells. Functional analysis of the collagenase‐3 gene promoter has allowed the identification of AP‐1 and OSE‐2 elements mediating, at least in part, its expression in both normal and pathological conditions.
Regulation of cell adhesion by PAI‐1
Authors: LOSKUTOFF DAVID J. , CURRIDEN SCOTT A. , HU GENG , DENG GANG
Published: August 2009

Type I plasminogen activator inhibitor (PAI‐1) is the primary inhibitor of tissue‐and urokinase‐type plasminogen activators. It circulates in plasma complexed with vitronectin (VN), the primary PAI‐1 binding protein. The somatomedin B (SMB) domain of VN contains both the high affinity PAI‐1 binding site and the specific site for urokinase plasminogen activator receptor (uPAR). PAI‐1 is able to regulate uPAR‐mediated cell adhesion by competing with uPAR for VN binding. Binding of PAI‐1 to SMD may also affect integrin‐mediated cell adhesion to VN by hindering integrin binding to the RGD sequence adjacent to the uPAR binding site.
Human homozygous type I plasminogen deficiency and ligneous conjunctivitis
Authors: MINGERS ANNE‐MARIE , PHILAPITSCH ANTON , ZEITLER PETRA , SCHUSTER VOLKER , SCHWARZ HANS PETER , KRETH HANS WOLFGANG
Published: August 2009

On the basis of a questionnaire sent to the ophthalmology departments of hospitals throughout Germany, 10 patients with ligneous conjunctivitis or pseudomembranous disease, ranging in age from 1 to 71 years were identified. All 10 patients had severely reduced plasminogen levels. Genetic analysis revealed homozygous type I plasminogen deficiency (which had not previously been described in humans) in 7 patients and compound heterozygous plasminogen deficiency in 1 patient. Clear differentiation was not possible in 2 patients. Most of the parents had heterozygous plasminogen deficiency. None of the patients had experienced any episodes of thrombosis. Additionally, the following observations were made: 1) Levels of polymorphonuclear (PMN)‐elastase protein were markedly elevated in 6 of 6 patients and 10 of 11 parents tested, and levels were higher in homozygotes than in heterozygotes. 2) Hereditary factor XII deficiency was found in 3 of 6 patients tested. 3) Cl‐inhibitor was elevated in 2 of 4 patients, prekallikrein was elevated in 1 of 4 patients, and plasminogen activator inhibitor type 1 was elevated in 1 of 4 patients. Infusions of lys‐plasminogen concentrate induced pronounced fibrinolytic activity as indicated by high levels of D‐dimer, increases in plasmin‐antiplasmin complex and decreases in polymorphonuclear elastase. Cl‐inhibitor, prekallikrein and PAI‐1 normalized after repeated infusions of lys‐plasminogen. In contrast to dysplasminogenemia, severe type I plasminogen deficiency might be seen as a problem of extravascular space, in particular of the mucous membranes, possibly triggered by mechanically induced or inflammatory lesions of the vessels supplying the tissue.
Programmed cell death and the caspases
Authors: SALVESEN GUY S.
Published: August 2009

Members of a family of cysteine proteases known as caspases orchestrate the intracellular biochemical events that enable animal cells to kill themselves by apoptosis. To counteract the apoptotic response to infection, some viruses have adapted and evolved proteins that specifically block caspases. More recently, it has been demonstrated that endogenous proteins belonging to the IAP family can regulate apoptosis by directly inactivating some of the caspases involved in initiating and executing programmed cell death.
Cathepsin D in cancer metastasis: A protease and a ligand
Authors: ROCHEFORT HENRI , LIAUDET‐COOPMAN EMMANUELLE
Published: August 2009

Cathepsin D (cath‐D) overexpression in breast cancer cells is associated with increased risk of metastasis in patients according to several clinical studies. No alterations of pro‐cath‐D structure or activation have been demonstrated in cancer cells. However, overexpression and dysrouting of pro‐cath‐D in illegitimate compartments could have consequences on tumor progression. Transfection of a human cDNA cath‐D expression vector increases the metastatic potential of 3Y1‐Ad12 embryonic rat tumorigenic cells when intravenously injected into nude mice. The mechanism by which cath‐D increases the incidence of clinical metastasis seems to involve increased cell growth and decreased contact inhibition rather than escape of cancer cells through the basement membrane. Different mechanisms are discussed by which cath‐D could act as a protease following its activation or as a ligand of different membrane receptors at a more neutral pH.
The urokinase receptor. A cell surface, regulated chemokine
Authors: BLASI FRANCESCO
Published: August 2009

Mice deficient for the urokinase plasminogen activator (uPA) gene are deficient in the recruitment of T cells and macrophages and succumb to bacterial infections. High levels of uPA or of its receptor (uPAR, CD87) are produced in human cancers and are strong prognostic indicators of relapse. Thus uPA and uPAR have a profound influence on cell migration. This set of molecules is known to regulate surface proteolysis, cell adhesion and chemotaxis. We have investigated the mechanism involved in uPAR‐dependent chemotaxis. Chemotaxis is induced through an uPA‐dependent conformational change in uPAR which uncovers a very potent chemotactic epitope acting through a pertussis‐toxin sensitive step and activating intracellular tyrosine kinases. The epitope is located in the linker region between domain D1 and D2 of uPAR. Binding of uPA transforms uPAR from a receptor for uPA into a pleiotropic ligand (“activated uPAR”) for other still unidentified surface molecules. Through these “adaptors”, uPAR causes cytoskeletal changes, activation of kinases and directional cell migration. The conformational change can be substituted by cleavage between domain D1 and D2, in an area that can be cleaved by uPA itself at high efficiency.
Matrilysin in early stage intestinal tumorigenesis
Authors: FINGLETON BARBARA M. , GOSS KATHLEEN J. HEPPNER , CRAWFORD HOWARD C. , MATRISIAN LYNN M.
Published: August 2009

The demonstration that matrix metalloproteinases [MMPs] play an active role in the invasion and metastasis stages of tumor progression has led to the development of a new class of anti‐metastatic chemotherapeutic agent, the matrix metalloproteinase inhibitors [MMPIs]. We present evidence to suggest that the MMP matrilysin, in particular, plays an essential role in much earlier stages of intestinal tumorigenesis. Matrilysin is detected in a high percentage of pre‐invasive lesions, in contrast to its absence in most normal tissues, and is expressed by the epithelial‐derived tumor cells. Manipulating levels of this enzyme in vitro results in cell lines with enhanced tumorigenic potential, while ablating the gene in vivo leads to a significant reduction in tumor number in two different animal models of intestinal tumorigenesis. Additionally, regulation of matrilysin gene expression appears to be under the control of genetic pathways which are activated very early in the tumor development sequence. Although the precise mechanism by which matrilysin activity contributes to tumor formation is not yet clear, we propose that MMPIs may be of benefit as chemopreventative agents in addition to their therapeutic potential for metastatic disease.
Tissue inhibitors of metalloproteinases (TEMP) in invasion and proliferation
Authors: HENRIET PATRICK , BLAVIER LAURENCE , DECLERCK YVES A.
Published: August 2009

Tissue inhibitors of matrix metalloproteinases (TIMPs) are a family of natural inhibitors that control the activity of matrix metalloproteinases (MMPs) in the extracellular matrix (ECM). Four members of this family have been so far characterized in a variety of species. These inhibitors share a similar structural feature characterized by the presence of 12 cysteine residues involved in disulfide bonds and a similar function by their ability to form inhibitory complexes with MMPs. The role of TIMPs in cancer has been the subject of conflicting reports with an antitumor activity reported by some investigators and a growth stimulation activity reported by others. Here we will discuss a series of data obtained in our laboratory supporting a role of TIMPs not only as inhibitors of invasion but also as regulators of cell growth. Using placental development as an example of a regulated invasive process, we have observed that the levels of TIMP‐2 and TIMP‐3 steadily increase between day 14.5 and 17.5 post‐coitus. TIMPs are selectively expressed by spongiotrophoblastic cells that separate the labyrinthine zone, rich in fetal blood vessels and maternal blood sinuses, from the zone of giant cells forming the border between fetal and maternal tissues. TIMPs are also potent inhibitors of tumor growth in vivo. In melanoma cells, we have previously reported that over‐expression of TIMP‐2 inhibits the growth of tumors implanted in the skin of scid mice. This growth inhibition seems independent of angiogenesis but dependent on the collagen matrix. We observed that in the presence of fibrillar type I collagen, melanoma cells undergo a growth arrest at the G1 to S interphase transition of the cell cycle. This arrest is specific to the fibrillar structure of collagen because it is not observed in the presence of non‐fibrillar collagen or other ECM components. It is associated with a specific upregulation of the cyclin inhibitor p27KIPI. The data therefore indicate that anchorage independent cells remain sensitive to growth regulatory signals that originate from the ECM and that these signals can specifically block tumor cell cycle. Thus our concept of the role of protease inhibitors such as TIMPs in cancer has substantially changed from an initial focus on inhibition of tumor invasion and metastasis to a broader focus on being molecules that‐via their function as regulators of the ECM homeostasis‐can control tumor cell growth.
An odyssey from breast to bone: Multi‐step control of mammary metastases and osteolysis by matrix metalloproteinases
Authors: LOCHTER ANDRÉ , BISSELL MINA J.
Published: August 2009

Development of metastases distant to the primary site of solid tumors marks late stages of tumor progression. Almost all malignant mammary tumors are carcinomas arising from the breast epithelium, but the morphological and molecular alterations in the mammary stroma surrounding the premalignant and the growing tumor contribute to its conversion into neoplastic tissue. Two parameters are critical for initiation of the metastatic process and access of tumor cells to the circulation. These are the ability of tumor cells to invade the basement membrane and the stroma, and the neovascularization of breast tumor tissue. A major site for development of distant metastases is the skeleton. After colonizing the bone, tumor cells promote a cascade of events leading to recruitment of osteoclasts and subsequent osteolytic bone destruction. A ubiquitous theme of neoplastic progression of breast tumors is the overproduction of matrix metalloproteinases. In this review, we summarize the recent insights into the functional consequences of matrix metalloproteinase expression and activation during malignant conversion in the breast, and after bone colonization. The current literature supports the hypothesis that matrix metalloproteinases play a key role in the metastatic expansion of most, if not all, mammary tumors and in the ensuing bone loss.
Membrane‐type matrix metalloproteinases
Authors: SEIKI MOTOHARU
Published: August 2009

Matrix metalloproteinases (MMP) degrade components of extracellular matrix (ECM), and thereby regulate formation, remodeling and maintenance of tissue. Abnormal function of cell surface proteases associated with malignant tumors may contribute directly to the invasive and malignant nature of the cells. Among the MMP's associated with the tumor cell surface, gelatinase A is believed to be particularly important, since it degrades type IV collagen, and is activated in a tumor specific manner, correlating with tumor spread and poor prognosis. Activation of pro‐gelatinase A is uniquely regulated by a cell‐mediated mechanism. This study describes an in vitro model that mimics the cell‐surface activation mechanism. The expression of MT‐MMP could not be detected in normal epithelial cells, but can be seen in transformed epithelial carcinoma cells.
Plasminogen activation in human leukemia and in normal hematopoietic cells
Authors: MUSTJOKI SATU , ALITALO RIITTA , STEPHENS ROSS W. , VAHERI ANTTI
Published: August 2009

The active process of pericellular proteolysis is central in tumor invasion, and in particular the essential role of the urokinase‐type plasminogen activator (uPA) is well established. uPA‐mediated plasminogen activation facilitates cell migration and invasion through extracellular matrices by dissolving connective tissue components. uPA, its receptor (uPAR) and plasminogen activator inhibitor‐1 (PAI‐1) are enriched in several types of tumors. The importance of proteolysis and especially plasminogen activation is less clear in hematopoietic malignancies than in solid tumors. However, patients with leukemia have an increased tendency to bleeding, not always attributable to thrombocytopenia, and tissue infiltration by leukemic cells, processes in which plasminogen activation may be involved. Several studies have indicated that plasminogen activators (PAs) are highly expressed by cultured leukemia cells. Furthermore, differing from adherent tumor cells, leukemic cells have an enhanced capacity to activate pro‐uPA and mainly the active form of uPA is released to culture medium. Ex vivo studies have shown that uPAR, uPA and its inhibitors can be found on the surface of normal blood cells and on the blast cell surfaces from patients with acute leukemia as well as from plasma samples. Elevated levels of PAs and their inhibitors have been detected in leukemic cell lysates. Few studies have tried to demonstrate a correlation between prognosis of leukemia and levels of plasminogen activators. More in vivo studies are needed to show, if any of the factors of the plasminogen activation process can be used as tools in subclassification or as markers for prognosis in leukemia. This review article will focus on the in vivo studies of plasminogen activation in leukemia and will present several in vitro findings on PAs in normal leukocytes and leukemic cell lines.
Clinical relevance of the urokinase plasminogen activator system in breast cancer
Authors: LOOK MAXIME P. , FOEKENS JOHN A.
Published: August 2009

Until recently clinical features and the hormone‐receptor status were the only factors used to select systemic (adjuvant) treatment for breast cancer patients. Other biological factors are needed as well to predict the probability of relapse and response with more certainty. The uPA‐system is such a prognostic and predictive factor in breast cancer. In this review, the results of research groups that have related relapse‐free survival to the quantitative levels of uPA‐system proteins and/or activities are discussed. Only studies that described the results from assays on cytosols or triton extracts of breast tumours were included. The levels of uPA‐system proteins help to predict the probability of relapse and response, and knowledge of the expression levels of the various components of the uPA‐system may lead to new treatment modalities targeted on specific properties of the uPA‐system.
The urokinase plasminogen activator receptor in blood from healthy individuals and patients with cancer
Authors: BRÜNNER NILS , NIELSEN HANS JØRGEN , HAMERS MARIA , CHRISTENSEN IB JARLE , THORLACIUS‐USSING OLE , STEPHENS ROSS W.
Published: August 2009

The cell surface plasminogen activation system functions in promoting tumor dissemination, and is facilitated by a glycolipid anchored three domain receptor for urokinase. This receptor can also be found in a soluble form (suPAR) in extracts of tumors, as well as in plasma from both healthy individuals and cancer patients. The suPAR in plasma consists of the intact three domain protein, but neither the precise mechanism of its release from cell surfaces, nor its biological function are understood. Increased levels of plasma suPAR have been found in patients with cancers of the lung, breast, ovary, and colon, and recent data now indicates that the level of the molecule is related to patient prognosis.
Urokinase receptor antagonists: discovery and application to in vivo models of tumor growth
Authors: TRESSLER ROBERT J. , PITOT PATRICE A. , STRATTON JENNIFER R. , FORREST LOUISE D. , ZHUO SHAOQIU , DRUMMOND ROBERT J. , FONG SUSAN , DOYLE MICHAEL V. , DOYLE LAURA V. , MIN HYE YEONG , ROSENBERG STEVEN
Published: August 2009

Urokinase receptor antagonists based on the growth factor domains of both human and murine urokinase which show sub‐nanomolar affinities for their homologous receptors have been expressed as recombinant proteins. Further modification of these molecules by preparing fusions with the constant region of human IgG has led to molecules with high affinities and long in vivo half‐lives. Smaller peptidic inhibitors have been obtained by a combination of bacteriophage display and peptide analog synthesis. All of these molecules inhibit the binding of the growth factor domain of uPA to the uPA receptor and enhance binding of the uPA receptor to vitronectin. Protein uPA receptor antagonists were tested in an in vivo tumor model using the human breast carcinoma MDAmb231 in immunodeficient mice. Both human and murine receptor antagonists showed significant inhibition of primary tumor growth, demonstrating that in vivo, both tumor and stromal cell uPA receptor dependent plasminogen activation can modulate tumor growth.
Clinical studies with matrix metalloproteinase inhibitors
Authors: BROWN PETER D.
Published: August 2009

Matrix metalloproteinases (MMPs) have been implicated in the invasive growth and spread of tumours. Potent and selective inhibitors of MMPs have been synthesized. These inhibitors can prevent tumour invasion in vitro and have suppressed tumour growth and metastasis in animal cancer models. Several MMP inhibitors have now reached clinical trials. Phase I studies indicate that the inhibitors can be given by mouth and that over the short term they are well tolerated. Longer, randomised studies in cancer patients are now underway.
The long‐term effect of a short course of transforming growth factor‐β1 on rat articular cartilage
Authors: ITAYEM RAED , MENGARELLI‐WIDHOLM SILWA , REINHOLT FINN P.
Published: August 2009

The long‐term effect of 3 days' topical administration of TGF‐β1 on unloaded articular cartilage in growing rats was investigated. Three to five rats were sacrificed on days 15, 30, 45, 60 and 90 after the last injection and the patellas were subjected to light and electron microscopic evaluation. The patellas showed age‐related changes when entering the maturation phase. Absence of a hypertrophic zone and formation of a subchondral bone plate were observed in both treated rats and controls from that time point. Reduction of total cell amount was observed between older and younger patellas in both treated rats and controls. TGF‐β1 treatment resulted in accelerated maturation and ageing. Furthermore, the administration of TGF‐β1 resulted in a higher unmineralized cartilage with an increased total amount of cells in the intermediate zone. Matrix areas showing ultrastructural features of disturbed matrix composition were seen in the deeper part of this zone at all time points, but in the treated patellas only. The present results indicate that TGF‐β1 treatment may induce changes in articular cartilage in some respects similar to those seen in the early stages of degenerative and inflammatory joint diseases.
Isolation of mycobacteria from indoor swimming pools in Finland
Authors: IIVANAINEN EILA , NORTHRUP JILL , ARBEIT ROBERT D. , RISTOLA MATTI , KATILA MARJA‐LEENA , VON REYN C. FORDHAM
Published: August 2009

The presence of mycobacteria in seven indoor pools in Finland was evaluated by multiple culture methods. Replicate samples, with and without inactivation of chlorine by sodium thiosulfate, were cultured in two laboratories. Laboratory I used two methods: (A) no decontamination and (B) cetylpyridinium chloride (0.005%, 20 min); and Laboratory II two methods: (C) cetylpyridinium chloride (0.005%, 18 h) and (D) oxalic acid (5%, 15 min). Samples processed by methods (A) and (B) were cultured on different egg media of pH 6.3 or 5.8; by method (C) on Middlebrook and Cohn 7H10 (+OADC) agar of pH 5.5; and by method (D) on Middlebrook and Cohn 7H10 agar (+OADC) with cycloheximide (500 μg/ml). Mycobacteria were recovered from five (71%) of seven pools. Detection of mycobacteria depended on the method used. High isolation rates (36–46% of the samples) were obtained by methods (A), (B) and (D). Contamination was a problem only with method (A). Inactivation of chlorine had a variable impact on mycobacterial detection. Isolates included M. kansasii, M. gordonae, M. fortuitum complex, M. sphagni, and M. vaccae, as well as M. simiae‐like and M. chubuense‐like organisms. In addition, a group of slowly growing and a group of rapidly growing isolates with previously unknown fatty acid and alcohol composition were isolated. No M. avium was detected. Mycobacterial counts were highest in a small pool with high temperature, low pH, and low content of free available chlorine.
Numerical abnormalities of chromosome 7 in interphase cell nuclei of breast carcinoma have no impact on immunohistochemically determined EGFR status
Authors: SAUER TORILL , BERAKI KAHSAI , JEBSEN PETER W. , NÆSS ODDVAR
Published: August 2009

Aim of study: To investigate the relationship between epidermal growth factor receptor (EGFR) status and numerical aberrations of chromosome 7 in breast carcinomas. Design: In situ hybridization (ISH) of interphase cell nuclei on air‐dried fine‐needle aspirates (FNAC) from 33 breast carcinomas was evaluated for numerical abnormalities in chromosome 6, 7, 12 and 17. Immunohistochemical staining of EGFR was performed on corresponding histological specimens. Results: 78% of the tumours were aneuploid by ISH. Aneusomy of chromosome 7 was found in 18 cases (60%). EGFR overexpression was observed in 30% of the carcinomas, and seven of nine were aneuploid by ISH. The same percentage of chromosome 7 aneusomy was found in both EGFR‐positive and‐negative cases. Five of seven EGFR‐positive tumours revealed aneusomy of chromosome 7. Conclusion: Numerical gain of chromosome 7 is a common finding, occurring in about 60% of breast carcinomas. Most EGFR‐positive tumours are aneuploid and show numerical gain of chromosome 7, but abnormal numbers of chromosome 7 have no impact on the EGFR status.
Survival and function of phagocytes in blood culture media
Authors: FISCHER THEA K. , PRAG JØRGEN , KHARAZMI ARSALAN
Published: August 2009

The survival and function of human phagocytes in sterile aerobic and anaerobic blood culture media were investigated using neutrophil morphology, white blood cell count in a haemoanalyser, flow cytometry, oxidative burst response, and bactericidal effect in Colorbact® and Septi‐Chek® blood culture media and Bact/Alert®. When comparing agitation to stationary incubation no difference in phagocytic activity was found. The methods showed the same trends demonstrating that the phagocytes' viability and activity were prolonged by oxygen and shortened by anaerobic conditions and sodium polyethanol sulfonate (SPS). Best preserved activity and viability were found in the aerobic media containing less than 0.5 g/l SPS, in which significant phagocyte oxidative burst and bactericidal activity were found up to 4 days after inoculation. Considering that the majority of bacteremias are due to aerobic or facultatively anaerobic bacteria, the present data suggest that most bacteria may be recovered by the use of one aerobic bottle with SPS concentration below 0.5 g/l to protect meningococci and other SPS‐sensitive bacteria and one above 0.5 g/l to stop phagocytic activity, plus one anaerobic bottle with SPS below 0.5 g/l.
Effects of short‐chain fatty acids on in vitro bacterial growth of Bacteroides fragilis and Escherichia coli
Authors: MORTENSEN FRANK V. , MØLLER JENS KJØLSETH , HESSOV IB
Published: August 2009

Short‐chain fatty acids (SCFA) are produced in the large bowel of nonruminant mammals by bacterial anaerobic fermentation. The aim of the present study was to investigate the effects of SCFA on the in vitro growth of Bacteroides fragilis and Escherichia coli. B. fragilis and E. coli isolated from fresh human clinical samples and a reference strain for each species were incubated in a meat infusion broth with increasing amounts of SCFA and grown under anaerobic conditions at a temperature of 37°C. Bacterial growth was estimated by spectrophotometry. Rate of growth was calculated from the logarithmic growth phase. SCFA, in concentrations normally found in the human colon, had a significant (p<0.01) inhibitory effect of the in vitro growth rate for E. coli, while they were without effect on the in vitro growth rate of B. fragilis. It may be concluded that under in vitro conditions SCFA had growth‐inhibitory effects on E. coli, while they had no effect on B. fragilis.
Evaluation of three lines of immunodeficient mice for the study of spontaneous metastatic tumors
Authors: GALLO‐HENDRIKX ELEANOR , PERCY DEAN , COPPS JOHN , McKEOWN BRENDAN , QUINTON MARGARET , McMILLAN IAN , CROY B. ANNE , WILDEMAN ALAN G.
Published: August 2009

Various immunodeficient animals have been used as transplantation recipients for studying the growth of human tumors. We have been assessing the value of immunodeficiencies for the study of naturally arising tumors, using a model system of transgenic mice that spontaneously develop cancer of the pancreas as a result of elastase promoter‐driven expression of the large tumor antigen gene of simian virus 40. We previously reported the establishment of transgenic mice that carried the SCID and/or beige mutations, eliminating B‐and T‐cell function and reducing lytic NK cell activity, respectively. In SCID beige animals, metastasis rates and target organs for metastases were similar to those observed in humans with pancreatic cancer. We describe here analysis of subsequent more highly inbred generations of these mice. The data show that inbreeding has almost negated the value of these immunodeficiencies for enhancing disease progression, and we observe high rates of metastasis even in immunocompetent animals. The data suggest that SCID and beige immunodeficiencies may not always have the same value for the modeling of spontaneous tumors as they do for the study of xenografts.
Antibiotic susceptibility of blood culture isolates after nearly two decades with netilmicin and ampicillin in neonatal septicaemia
Authors: RØNNESTAD A. , ABRAHAMSEN T. G. , GAUSTAD P. , FINNE P. H.
Published: August 2009

The aim of the study was to investigate the in vitro antibiotic susceptibility of blood culture isolates after almost 20 years with ampicillin and methicillin as empirical treatment for neonatal septicaemia. All blood culture isolates and their antibiograms obtained in a single tertiary neonatal intensive care unit from 1 January 1989 to 31 December 1994 were reviewed. Two hundred and six blood cultures from 181 infants containing 223 bacterial and 11 fungal isolates were identified during 4416 admissions. Fifteen (6.7%) of the bacterial isolates were resistant to ampicillin and netilmicin. Fourteen per cent of the staphylococcal spp. were susceptible to penicillin while more than 90% were susceptible to netilmicin. The coagulase‐negative staphylococci (CONS) were resistant to netilmicin, methicillin and gentamicin in 12%, 49% and 65%, respectively. Eighty‐nine per cent of the methicillin‐resistant CONS were susceptible to netilmicin as opposed to 17% to gentamicin (p<0.001). Except for one strain of Acinetobacter sp., all Gram‐negative bacteria were susceptible to netilmicin. Our data show that the ampicillin‐netilmicin combination still provides a high in vitro coverage (93%) against bacteria identified in blood cultures from newborns in our unit. Netilmicin has a significantly better in vitro effectiveness against CONS than gentamicin.
Comparison of three different methods in monoclonal antibody‐based detection of Streptococcus agalactiae protein serotype markers
Authors: MOYO SYLVESTER R. , MÆLAND JOHAN A. , BEVANGER LARS
Published: August 2009

Surface‐exposed proteins are important serotype markers in Streptococcus agalactiae (group B streptococci; GBS). The proteins include the c proteins cα and cβ, the R4 protein and a protein provisionally called P. For all of these markers, protein‐specific monoclonal antibodies (MAbs) have been generated. We have compared whole‐cell‐based fluorescent antibody testing (FAT), ELISA, and dot blotting for MAb‐based detection of these proteins by testing a panel of 52 GBS isolates of different capsular antigen types. Of a total of 208 observations with each of the tests, positive signalling in the dot assay was observed in 32.2%, with ELISA in 27.8%, and with FAT in 26.4% of the recordings. Discordant results were noted most frequently with the c13 and cα MAbs. In the case of cα the reason for the discordant test results was further examined and it appeared that this could be attributed to low level expression of the cα protein, although structural variations of cα proteins cannot be excluded. Our findings favour dot blotting as the method of choice although we consider all three methods acceptable for serotyping of GBS.
Health condition of the Baltic grey seal (Halichoerus grypus) during two decades
Authors: BERGMAN ANDERS
Published: August 2009

Results obtained at postmortem examinations of 159 Baltic grey seals during the 20‐year period 1977–1996 are presented. The investigation was initiated due to a serious reduction of the Baltic grey and ringed seal populations. Earlier, reduced reproductive ability with occlusions and stenoses of the uterus, as well as a disease complex in adult individuals of both sexes, was reported. The disease complex comprised lesions of claws, skull bone, intestine (colonic ulcers), kidneys (glomerulopathy, tubular cell proliferations), arteries (sclerosis) and adrenals (cortical hyperplasia, cortical adenomas). Besides occlusions and stenoses, tumours (leiomyomas) were common in the uterus. This report focuses on the results of a time‐trend study covering the two decades 1977–1986 and 1987–1996. The prevalences (%) in the two decades of moderate to severe lesions of claws, intestine, arteries and adrenals are compared, as well as the prevalences of lesions of the female reproductive organs and rate of pregnancy. A similar comparison was made of animals born before 1980 and those born after 1979, in order to investigate a possible relation between the evident decrease in PCB and DDT pollution of the Baltic which occurred in the 1970s and seal health. A positive time trend respecting gynaecological health was confirmed, with a decreased prevalence of uterine obstructions, from 42 to 11%, and an increased prevalence of pregnancies, from 9 to 60%. The high incidence of uterine tumours (leiomyomas) seems to have decreased slowly (from 53 to 43%). Of special interest is the increased prevalence of colonic ulcers in young animals. The findings indicate that the food consumed by the Baltic seals may contain “new” or increased amounts of hitherto unidentified toxic factors which affect their immune system.
Spermatocytic seminoma as compared to classical seminoma: An immunohistochemical and DNA flow cytometric study
Authors: KRAGGERUD SIGRID M. , BERNER AASMUND , BRYNE MAGNE , PETTERSEN ERIK O. , FOSSÅ SOPHIE D.
Published: August 2009

Based on immunohistochemistry (IHC) and DNA ploidy, different paths of carcinogenesis have been suggested for spermatocytic seminoma (SS) and classical seminoma (CS). The present study extends current knowledge on the above parameters. Method. Seventeen SSs and twenty‐two CSs were assessed by IHC for placental‐like alkaline phosphatase (PLAP), c‐kit, cytokeratin and adhesion carbohydrate molecyles. All SSs and 11 CSs were also analysed for DNA ploidy. Results. All CSs, but none of the SSs, were positive for PLAP. C‐kit positivity was found in 7 of 17 SSs and in all CSs. The other IHC parameters were similarly distributed among the evaluated SSs and CSs. Fourteen SSs were diploid or polyploid, and three were aneuploid. All CSs were aneuploid. Conclusion. The new observation of c‐kit positivity in about 40% of SSs suggests that at least some of the SSs originate from primordial cells. The predominantly diploid or polyploid DNA pattern indicates that SSs follow a pathogenetic pathway which is most probably different from that of CSs.
Stereological quantification of mast cells in human synovium
Authors: DAMSGAARD TINE ENGBERG , SØRENSEN FLEMMING BRANDT , HERLIN TROELS , SCHIØTZ PETER OLUF
Published: August 2009

Mast cells participate in both the acute allergic reaction as well as in chronic inflammatory diseases. Earlier studies have revealed divergent results regarding the quantification of mast cells in the human synovium. The aim of the present study was therefore to quantify these cells in the human synovium, using stereological techniques. Different methods of staining and quantification have previously been used for mast cell quantification in human synovium. Stereological techniques provide precise and unbiased information on the number of cell profiles in two‐dimensional tissue sections of, in this case, human synovium. In 10 patients suffering from osteoarthritis a median of 3.6 mast cells/mm2 synovial membrane was found. The total number of cells (synoviocytes, fibroblasts, lymphocytes, leukocytes) present was 395.9 cells/mm2 (median). The mast cells constituted 0.8% of all the cell profiles present in the synovium. A significantly positive correlation was demonstrated between the number of mast cells and the total number of cells. Thus, the present study reports stereological quantification of the mast cells and the total number of cells in synovium from patients with osteoarthritis. A possible link between the mast cell and osteoarthritis is discussed upon obtaining a precise estimate of cell profiles in human synovium.
The effect of hydrocarbon chain length, pH, and temperature on the binding and bactericidal effect of amphiphilic betaine esters on Salmonella tvphimurium
Authors: AHLSTRÖM B. , THOMPSON R. A. , EDEBO L.
Published: August 2009

Amphiphilic betaine esters are quaternary ammonium compounds (QAC) with rapid microbicidal action. They are often labeled ‘soft antimicrobial agents’, since the compounds hydrolyze spontaneously into betaine and fatty alcohols, thus not only losing their surface active properties and toxicity but also becoming amenable to metabolic use. The present results show that the bactericidal effects of 1‐decyl (B10), 1‐dodecyl (B12), and 1‐tetradecyl (B14) betaine esters on Salmonella typhimurium 395 MS decreased with decreasing hydrocarbon chain lengths, decreased at pH below neutral, and were lower at 0°C that at 30°C. At least part of the decreased effect at pH 4.0 as compared to pH 6.0 can be explained by reduced binding. However, reduced binding cannot explain the decrease in the microbicidal effect at 0°C since the binding of B 14 was the same at 0°C and 30°C although 10–30 times higher concentrations were required at 0°C to achieve the same microbicidal effect as at 30°C. Neither can differences in binding explain the great differences seen in microbicidal effect between QAC with different chain lengths. It is proposed that the membrane deformation resulting in killing of S. typhimurium is more efficiently achieved with QAC with longer hydrocarbon chains and that reduced fluidity of the outer membrane of the bacteria at lower temperatures antagonizes the bactericidal effect. Charge interaction seems to be more important for the binding and bactericidal effect for the QAC with shorter hydrocarbon chains. The different effects of pH, temperature, and hydrocarbon chain length on binding, bactericidal effect, and hydrolysis have to be taken into account when optimizing disinfection and the subsequent elimination of disinfectants.
Secular trends in incidence and mortality of bacteraemia in a Danish county 1981–1994
Authors: MADSEN KREESTEN MELDGAARD , SCHØNHEYDER HENRIK CARL , KRISTENSEN BRIAN , SØRENSEN HENRIK TOFT
Published: August 2009

We estimated the incidence and mortality of bacteraemia in the County of North Jutland and examined factors that could explain the changes observed. A population‐based survey of bacteraemia was conducted in the Danish County of North Jutland during 1981–1994. Data were retrieved from a regional bacteraemia register. The mortality was determined through linkage to the Danish Civil Registration System. A total of 7198 bacteraemias were detected, and the annual incidence increased from 76 per 100,000 person‐years in 1981 to 153 in 1994. One major determining factor was a change in blood culture system with a higher volume of blood per sample, but annual numbers of blood cultures also increased. The 30‐day mortality rate increased from 17 to 40 per 100,000 person‐years during the study period, whereas the case‐fatality rate remained constant (23.6%; 95% confidence intervals 22.6%‐24.6%). The number of bacteraemias increased significantly. This observation could be explained only partly by changes in demography, in blood culture system, and in diagnostic activity. The case fatality rate remained constant despite the fact that more people were diagnosed with bacteraemia; this indicates that, with recent blood culture practice, more clinically significant bacteraemias are diagnosed.
Mink enteritis parvovirus
Authors: UTTENTHAL ÅSE , LUND EBBA , HANSEN MOGENS
Published: August 2009

Feces from mink with acute mink enteritis were pooled and then allowed to dry out in open tubes kept under a roof in an open shed for one year starting in January. Samples of feces were harvested approximately once a month. These were reconstituted to their original volume and tested for antigen content and infectivity both in in vitro cell cultures and – on selected samples – in vivo. During the first 8 months, the antigen level in the feces samples decreased slowly. At this time point, a plateau was reached at 30–40% of the original viral antigen contents. The infectivity in vitro was unchanged for the first 5 months, but after mid‐summer it decreased abruptly to below the detection level. Based on the in vitro infectivity, 10 samples were selected for inoculation into mink to measure the in vivo infectivity. The transmission of the infection to the experimental animals was successful for all samples showing infective virus by cultivation. In addition, it was possible to infect mink using material harvested one month after the cell culture test had turned negative. One mink inoculated with material collected in October excreted virus. We conclude that parvovirus can survive for at least 5–10 months (or during the winter period) under natural conditions, but complete drying out seems to lead to its inactivation. Mechanical cleaning of the premises is thus as critical as disinfection since virus can only survive the dry summer period if protected by protein or buried in moist soil on the premises.
Chronic recurrent multifocal osteomyelitis: A great clinical and radiologic mimic in need of recognition by the pathologist
Authors: CHOW LOUIS T. C. , GRIFFITH JAMES F. , KUMTA SHEKHAR M. , LEUNG PING C.
Published: August 2009

The spectrum of histopathologic changes in four cases of chronic recurrent multifocal osteomyelitis encountered in our orthopedic outpatient clinic in the past 3 years was studied in conjunction with clinical and radiologic findings. All presented with pain with or without swelling in the affected region. Radiographically, the appearance of the lesions varied from a mixed picture of bone lysis and sclerosis with expansion to sclerosis alone to bone collapse. Bone scintigraphy demonstrated asymptomatic and separate foci of activity in all cases. Prior to biopsy, the clinical and radiologic differential diagnoses included Ewing's sarcoma, metastatic neuroblastoma, hematolymphoid malignancy, Langerhans cell histiocytosis and chronic infection, notably tuberculosis. The spectrum of histopathologic changes ranged from acute (acute inflammatory infiltration, active bone resorption and necrosis, reactive bone formation) to subacute (predominantly lymphocytic and plasma cell infiltration) to chronic inflammation (fibroblastic organization and bony sclerosis). Histologic changes correlated poorly with clinical features, but relatively well with radiologic findings. Lesional excision was performed in one case, cortical saucerization in another, while the final two cases received supportive treatment. All remained well 18–21 months post‐therapy. Chronic recurrent multifocal osteomyelitis is a great clinical and radiologic mimic, which merits recognition by the pathologist. Awareness of the spectrum of histologic features encountered enables a correct diagnosis to be made in the appropriate clinical setting. The patient can thus be reassured of a favorable prognosis.
Dialysis culture for determination of MIC and MBC of benzylpenicillin against Borrelia burgdorferi
Authors: STIERNSTEDT SUSANNE HAMMERS , TADESSE TEKLEWEINI , WRETLIND BENGT
Published: August 2009

Minimal inhibitory concentration (MIC) of benzylpenicillin (Pen G) against strains of Borrelia burgdorferi has earlier been determined by a recently developed dialysis culture technique which provides a constant concentration of Pen G. To further investigate this method, both MIC and minimal bactericidal concentration (MBC) of Pen G against B. burgdorferi were determined and the results were compared with those obtained by other authors using different methods. The incubation period was 7 days and subcultures for MBC were observed for a further 2 weeks. The study showed results of MIC and MBC similar to those of broth microdilution, indicating sensitivity, but lower values than the majority of MIC and MBC results reported by other authors using broth macrodilution. It is essential for the results of antibiotic sensitivity testing in vitro against slowly growing bacteria like Borrelia burgdorferi that the concentration of antibiotics such as Pen G, which are unstable in solution, is constant during the incubation period.
HLA‐DR expression is a significant prognostic factor in laryngeal cancer
Authors: SIKORSKA BEATA , DANILEWICZ MARIAN , WAGROWSKA‐DANILEWICZ MALGORZATA
Published: August 2009

HLA‐DR antigen expression in tumour cells was investigated in 68 laryngeal carcinomas. The tissue sections were studied by a morphometric method using a computer image analysis system. Although the highest number of HLA‐DR‐positive cells was observed in the groups with the lowest clinical stage, these differences did not reach statistical significance. Analysis of survival showed a significantly different survival time of patients classified as HLA‐DR positive (10% and more HLA‐DR+tumour cells) compared to those classified as HLA‐DR negative. There were no significant differences in survival times between patients with glottic and extraglottic cancers, or between patients with various grades of histological malignancy.
Intraosseous epithelioid malignant peripheral nerve sheath tumor of the phalanx
Authors: HIROKAWA MITSUYOSHI , SHIMIZU MICHIO , FUKUOKA KEIKO , TORIGOE NOBUYUKI , HINO YOSUKE , MIKAWA YOSHIHIRO , MANABE TOSHIAKI
Published: August 2009

We report the first case of intraosseous epithelioid malignant peripheral nerve sheath tumor (MPNST) occurring in the phalanx. The patient was a 50‐year‐old Japanese man with an intramedullary lytic lesion of the proximal phalanx. Microscopically, the tumor was composed of epithelioid cells or polygonal cells, forming large cell nests with central necrosis. Most tumor cells were diffusely and strongly immunopositive for S‐100 protein and vimentin, and negative for cytokeratin, epithelial membrane antigen, carcinoembryonic antigen, alpha‐smooth muscle actin, and HMB‐45. Laminin‐positive material was discontinuously demonstrated between the individual tumor cells. Electron microscopy showed prominent external lamina. Our case indicated that laminin is useful for differentiating epithelioid MPNST from metastatic carcinoma and malignant melanoma.