bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrastructural studies on the effect of transforming growth factor‐β1 on rat articular cartilage
Authors: ITAYEM RAED , MENGARELLI‐WIDHOLM SILWA , HULTH ANDERS , REINHOLT FINN P.
Published: August 2009

The destruction of articular cartilage in degenerative and inflammatory joint disease reflects an imbalance between synthesis and degradation of the structural components of the tissue. In previous, mainly in vitro studies, TGF‐β has been shown not only to play a role in controlling the synthesis of matrix components such as collagen and proteoglycans but also to influence their degradation. To elucidate the effect of local administration of TGF‐β on unloaded articular cartilage in growing rats, three animals were given intraarticular injections of TGF‐β for three consecutive days and sacrificed on the fourth. Perfusion fixation was combined with qualitative and quantitative evaluation (stereology) both at the light and electron microscopic level. Local administration of TGF‐β resulted in a decrease in height of the hypertrophic zone. Furthermore, the volume density of cells decreased and cells with a distinct morphology designated stellate cells appeared in this zone. In the same compartment, TGF‐β administration resulted in decreased pericellular collagen volume density while the volume density increased in the intermediate zone. The results of our investigation support and extend previous observations: TGF‐β does not only modulate the metabolism of articular cartilage in general, but the effect is targeted to specific subcompartments of the matrix. However, the result of this acute effect on the long‐term function of the tissue remains to be elucidated.
Purification of herpes simplex virus type 1 by density gradient centrifugation and estimation of the sedimentation coefficient of the virion
Authors: SATHANANTHAN B. , RØDAHL E. , FLATMARK T. , LANGELAND N. , HAARR L.
Published: August 2009

Purification of herpes simplex virus type 1 (HSV‐1) is often performed by centrifugation in gradients of various materials. A major problem with such procedures is a gradual decrease in the infectivity of the virus, probably due to the influence of the gradient material. In the present work we have compared Nycodenz gradients with Ficoll gradients for HSV‐1 purification. Both gradient materials have low osmolarities. The purity of the preparations recovered from the two gradients was similar, as measured by electron microscopy and two‐dimensional gel electrophoresis, and the yield of infectious virus was approximately the same. Szilágyi & Cunningham (22) reported previously that Ficoll gradients separate one band of complete virions and another band containing light particles devoid of nucleocapsids. In Nycodenz gradients we observed the same bands, and an additional third band which contained aggregates and disrupted particles. In this respect, the separation in Nycodenz is slightly superior to that in Ficoll. The purified HSV‐1 virions were subjected to analytical diffferential centrifugation and an S‐value of 670S was calculated for the virus.
Expression of colonization factor antigen I fimbriae by enterotoxigenic Escherichia coli; influence of growth conditions and a recombinant positive regulatory gene
Authors: HALVORSEN THOMAS , VALVATNE HÅVARD , GREWAL HARLEEN M. S. , GAASTRA WIM , SOMMERFELT HALVOR
Published: August 2009

Enterotoxigenic Escherichia coli (ETEC) may spontaneously lose the positive regulatory cfaR gene and thereby the capacity to express colonization factor antigen I (CFA/I). A recombinant plasmid harbouring the cfaR gene was transformed into cfaR‐negative mutant ETEC strains. CFA/I expression of wild‐type and cfaR‐transformed ETEC cultivated in different liquid media was quantified. At 37°C, a high level of CFA/I expression from wild‐type and cfaR‐transformed strains was observed after growth in CFA broth. Transformation enhanced CFA/I expression only marginally. The transformant cultures showed a considerable variation in CFA/I expression which was paralleled by the proportion of individual bacteria producing CFA/I. This heterogeneity could be explained by a variable tendency to structural CFA/I gene loss among individual cfaR‐transformed bacteria.
Mechanisms of methicillin resistance in staphylococci
Authors: BRAKSTAD ODD GUNNAR , A. MÆLAND JOHAN
Published: August 2009

The continuously high prevalence of methicillin‐resistant staphylococci (MRS) throughout the world is a constant threat to public health, owing to the multiresistant characteristics of these bacteria. Methicillin resistance is phenotypically associated with the presence of the penicillin‐binding protein 2a (PBP2a) not present in susceptible staphylococci. This protein has a low binding affinity for β‐lactam antibiotics. It is a transpeptidase which may take over cell wall synthesis during antibiotic treatment when normally occurring PBPs are inactivated by ligating β‐lactams. PBP2a is encoded by the mecA gene, which is located in mec, a foreign DNA region. Expression of PBP2a is regulated by proteins encoded by the plasmid‐borne blaR1‐blaI inducer‐repressor system and the corresponding genomic mecR1‐mecI system. The blaR1‐blaI products are important both for the regulation of β‐lactamase and for mecA expression. Methicillin resistance is influenced by a number of additional factors, e.g. the products of the chromosomal fem genes which are important in the synthesis of normal peptidoglycan precursor molecules. Inactivation of fem‐genes results in structurally deficient precursors which are not accepted as cell wall building blocks by the ligating PBP2a transpeptidase during antibiotic treatment. This may result in reduced resistance to β‐lactam antibiotics. Inactivation of genes affecting autolysis has shown that autolytic enzymes are also of importance in the expression of methicillin resistance. Methicillin resistance has evolved among earth microorganisms for protection against exogenous or endogenous antibiotics. Presumably the mec region was originally transferred from coagulase negative staphylococci (CNS) to Staphylococcus aureus (SA). A single or a few events of this kind with little subsequent interspecies transfer had been anticipated. However, recent data suggest a continuous horizontal acquisition by S. aureus of mec, being unidirectional from CNS to SA. Methicillin resistance may also be associated with mechanisms independent of mecA, resulting in borderline methicillin resistance. These mechanisms include β‐lactamase hyperproduction, production of methicillinases, acquisition of structurally modified normal PBPs, or the appearance of small colony variants of SA. Most MRS are multiresistant, and the mec region may harbour several resistance determinants, resulting in a clustering of resistance genes within this region.
A xenograft line of human teratocarcinoma established by serial transplantation in severe combined immunodeficient (SCID) mice
Authors: ABE YOSHIYUKI , OSHIKA YOSHIRO , OHNISHI YASUYUKI , SUTO RYUJI , TOKUNAGA TETSUJI , YAMAZAKI HITOSHI , KIJIMA HIROSHI , HIRAOKA NOBUYOSHI , UEYAMA YOSHITO , TAMAOKI NORIKAZU , NAKAMURA MASATO
Published: August 2009

We established a xenograft line of human teratocarcinoma (TC‐1) and characterized the pluripotency of differentiation of the neoplastic cells. A teratocarcinoma specimen obtained from a primary mediastinal lesion (22‐year‐old male patient) was inoculated subcutaneously into severe combined immunodeficient (SCID) mice. The carcinoma formed tumors in the mice. We established a xenograft line by serial passage of the tumor in vivo. The primary tumor was composed of papillary and pseudoglandular nests of highly atypical epithelial cells with foci of glomeruloid structures. The metastatic cells showed apparent production of mucin and differentiation to striated muscle. The xenograft line TC‐1 retained the basic histopathological features seen in the primary and metastatic cells. The xenograft line showed focal differentiation to cartilage through serial passages. Immunohistochemical studies with anti‐α‐fetoprotein (AFP) demonstrated positive immunoreactivity on the TC‐1 cells. Serum AFP levels were also elevated in the TC‐1‐bearing SCID mice. The human teratocarcinoma xenograft line TC‐1 will be useful for studying the differentiation mechanism in human totipotent stem cells.
Direct cytotoxic response of human lymphocytes to porcine PHA‐lymphoblasts and lymphocytes
Authors: BREVIG THOMAS , KRISTENSEN TOM
Published: August 2009

Transplantation of cells and organs from pigs to human beings offers potential treatment for medical conditions such as diabetes, kidney and heart failure, and Parkinson's disease. When the antibodymediated hyperacute rejection barrier is overcome, a xenograft may not be treated as an allograft by the human immune system. Without prior culture with porcine cells, human lymphocytes are cytotoxic to some porcine cells. Our aim was to functionally characterize this direct cytotoxic response to porcine PHA‐lymphoblasts and lymphocytes. Peripheral blood mononuclear cells from seven of eight human beings were cytotoxic to porcine PHA‐lymphoblasts in bulk chromium‐release assays, but not to the porcine lymphocytes from which the PHA‐lymphoblasts were derived. The NK cell‐sensitive cell line K562 only partly blocked the response to the PHA‐lymphoblasts. IL‐2‐expanded clones of human lymphocytes were able to discriminate between PHA‐lymphoblasts from two pigs and unable to lyse K562. When using IL‐2 to make the anti‐porcine cells proliferate under limiting dilution conditions, the proliferation and/or function of these cells did not conform to single‐hit kinetics. All the observations from experiments with cells in bulk cultures and as short‐term clones suggest that the direct cytotoxic response of human lymphocytes to porcine cells is heterogeneous and composed of a small population of in vivo‐activated T cells as well as NK cells.
Aedes albopictus (diptera: culicidae) is incompetent as a vector of hepatitis C virus
Authors: BELLINI ROMEO , CASALI BRUNO , CARRIERI MARCO , ZAMBONELLI CARLO , RIVASI PAOLO , RIVASI FRANCESCO
Published: August 2009

In laboratory experiments, Aedes albopictus females were fed hepatitis C virus (HCV)‐infected human blood with a unit‐feeding apparatus. Pools of engorged females were tested at various time intervals after their blood meal for the presence of HCV RNA using two methods in parallel: reverse transcription‐nested polymerase chain reaction (PCR) and PCR with the Amplicor HCV system. Comparable results were obtained with both methods. Mosquitoes were found to be positive only immediately and 24 h after feeding. Moreover, female progeny produced negative results. Our results indicate that the Ae.albopictus strain used is incompetent as a vector of HCV.
Restriction pattern variability of respiratory syncytial virus during three consecutive epidemics in Denmark
Authors: JOHANSEN JENS , CHRISTENSEN LAURIDS SIIG , HORNSLETH ALLAN , KLUG BENT , HANSEN KIRSTEN SKAMSTRUP , NIR MARTA
Published: August 2009

A PCR‐based assay was used to distinguish between respiratory syncytial virus (RSV) group A and B in order to analyze their prevalence in Denmark in three consecutive epidemics during the winters of 1992/93, 1993/94 and 1994/95. A total of 96 RSV strains isolated from hospitalized children were examined, showing alternation of group prevalence. Furthermore, the genetic variability of the RSV isolates was illustrated by restriction enzyme analysis of PCR products originating from a part of the F and G proteins that has been reported to be highly variable. We found that, in general, different genome types predominated each year, some types being present in consecutive epidemics, indicating a contribution of strains circulating unattended between outbreak seasons, while others seemed to disappear or became undetectable, being replaced by emerging types. Some of the genome types found seemed related to strains isolated up to more than two decades ago in other parts of the world. This indicates that the temporal fluctuation in predominance of genome types presumably caused by selective pressure exerted by host immunity is due to the favoring of strains from a pool of globally circulating, genetically relatively stable genome types, rather than a molecular evolution in strains induced or directed by immunoselective pressure.
Adenocarcinoma of the cervix and adenocarcinoma of the endometrium: distinction with PCR‐mediated detection of HPV DNA
Authors: HORDING U. , DAUGAARD S. , VISFELDT J.
Published: August 2009

The differential diagnosis between primary endocervical adenocarcinoma and adenocarcinoma originating in the endometrium may in some cases be difficult. The two cancer types have a different genesis, with human papillomavirus (HPV) as an important causal factor in the development of primary cervical carcinoma. In this study, the paraffin‐embedded cervical tissues from 23 patients with stage II endometrial carcinoma and from 50 patients with primary cervical adenocarcinoma were examined for HPV DNA of types 16, 18, and 33. HPV DNA was demonstrated in 70% of the primary endocervical adenocarcinomas and in none of the endometrial carcinomas. It is concluded that HPV detection may be useful in the differential diagnosis of some cases of cervical and endometrial adenocarcinoma.
Identification of porcine Pneumocystis carinii as a genetically distinct organism by DNA amplification
Authors: WAKEFIELD A. E. , KEELY S. P. , STRINGER J. R. , CHRISTENSEN C. B. V. , AHRENS P. , PETERS S. E. , BILLE‐HANSEN V. , HENRIKSEN S. Aa. , JORSAL S. E. , SETTNES O. P.
Published: August 2009

DNA was amplified from lung samples from three piglets infected with Pneumocystis carinii, using oligonucleotide primers designed to the P. carinii mitochondrial large subunit ribosomal RNA gene. The nucleotide sequence of the amplification product was determined and indicated lack of sequence variation among these pig‐derived P. carinii samples at this locus. The data showed that porcine P. carinii was genetically distinct from P. carinii isolated from other mammalian host species.
A case control study of chorioamniotic infection and histological chorioamnionitis in stillbirth
Authors: FOLGOSA ELENA , GONZALEZ CARLOS , OSMAN NAFISSA B. , HÄGERSTRAND INGA , BERGSTRÖM STAFFAN , LJUNGH ÅSA
Published: August 2009

In order to elucidate the role and aetiology of chorioamnionitis in stillbirth a case referent study was carried out in 58 pregnant women with late foetal death (cases) and in 58 pregnant women at term with live foetus (referents) matched for age and parity in Maputo Mozambique. Samples from women, stillborns and liveborns, were collected for microbiological and histological assessment. Histological chorioamnionitis was diagnosed in 96% of the cases and in 67% of the referents (OR=13.5; 95% CI: 2.9–123.9). Escherichia coli was the species most frequently isolated in stillborns; in 14/16 (88%) cases it was isolated from intracardiac fluid. E. coli was associated with chorioamnionitis in 28% of the stillborns as compared to 5% of the referents (OR=6.9; 95% CI: 1.4–65.4). No group B streptococci were recovered from any placenta or newborn. Vasculitis was present in 12 (21%) cases and in 3 (5%) referents (OR=4.8; 95%, CI: 1.2–27.7). Histological chorioamnionitis was thus associated with stillbirth. E. coli was common in stillborns. The presence of vasculitis in one fifth of the stillborns indicated that the foetus was alive at the onset of infection.
Gene amplification in the diagnosis of mycobacterial infections
Authors: SOINI HANNA , VILJANEN MATTI K.
Published: August 2009

The number and importance of infections caused by Mycobacterium tuberculosis and other mycobacterial species is increasing. Since the detection and identification of mycobacteria by conventional laboratory methods (cultivation, staining, and biochemical tests) is a slow and complex procedure, rapid diagnostic methods are urgently needed. Several amplification methods based on different techniques have been applied in the detection of mycobacteria directly from clinical specimens. Most experience has been obtained from different polymerase chain reaction (PCR) assays and their general performance is good. However, their sensitivity in the analysis of samples containing small amounts of mycobacteria or samples containing inhibitory substances has been low. Furthermore, the risk of false positives caused by contamination is high, and the clinical relevance of the results may be unclear. Thus, these gene amplification techniques are a valuable adjunct to the diagnosis of mycobacteria, but so far they cannot replace conventional microbiological methods.
Prognosis of radically operated breast carcinoma patients
Authors: RAABE N. K. , SCHISTAD O. , SAUER T. , BOFIN A. , KAARESEN R. , FOSSAA S. D.
Published: August 2009

A retrospective study of 167 consecutive radically treated breast cancer patients with histopathologically confirmed ductal carcinoma is presented. The aim was to establish the prognostic significance and reproducibility of histopathological grading done independently by two pathologists. Furthermore, the value of measurements of mean nuclear area (MNA) in the primary tumour was assessed. The two pathologists reviewed the same histological sections using a three‐point scoring system based on tubular stuctures, number of mitoses and nuclear pleomorphism. Grading was identical for 70% of the tumours (Kappa value 0.51). With increasing MNA, the fraction of poorly differentiated tumours increased. In the univariate analysis, tumour‐related survival was significantly related to histopathological grading when G3 tumours were compared to G1/G2 tumours (p<0.05). In the multivariate analysis, tumour size (pT category), lymph‐node status and grading were the only significant factors influencing patient outcome (p<0.05). MNA had no significant prognostic value. A combination of tumour size and histopathological grading identifies a group of node‐negative patients (pT2 G2/G3) who may have a less favourable prognosis and for whom adjuvant treatment may be beneficial.
Serum concentration of the aminopropeptide of type I procollagen in patients on haemo‐ and peritoneal dialysis
Authors: JENSEN P. B. , RASMUSSEN H. B. , PEDERSEN F. BANGSGAARD
Published: August 2009

Using an ELISA technique, the aminopropeptide of type I procollagen (PINP) was measured in serum from patients with chronic renal failure treated with haemodialysis (HD) (n = 19) or continuous ambulatory peritoneal dialysis (CAPD) (n=14), and compared to the commonly used bone markers. The serum concentrations for PINP, compared to healthy controls were significantly increased in both the HD‐group (p<0.00001) and the CAPD‐group (p<0.00001). In the HD‐group a close correlation was found between PINP and parathyroid hormone (PTH) (R(s)=0.745; p=0.00026) and between PINP and total alkaline phosphatase (R(s)=0.623; p=0.004), but in the CAPD‐group the corresponding p‐values were 0.17 and 0.06 only. No significant difference was found between the HD and CAPD patients with respect to serum levels of PINP, PTH, total alkaline phosphatase, or ionized calcium. In the HD‐patients, a significantly higher level of serum phosphate was found compared to in the CAPD‐patients. The present study demonstrates a close correlation between PTH, total alkaline phosphatase and PINP, which indicates that PINP might be used as a marker for evaluating increased bone turnover in patients with chronic renal failure treated with haemodialysis, and perhaps also in patients treated with peritoneal dialysis, and that the ideal biochemical parameters to analyse changes in bone metabolism in these patients may be a combination of the initiating hormone (PTH) and PINP as a marker of the effect of PTH on bone metabolism.
The homogeneity of hidradenitis suppurativa lesions
Authors: JEMEC GREGOR B. E. , THOMSEN BIRTHE M. , HANSEN ULLA
Published: August 2009

Recent data suggest that hidradenitis suppurativa is a disease of the follicle, but the histological homogeneity of findings over time and in different anatomical regions has not been verified. Its description may help towards a better classification of the follicular diseases. Correct classification provides both knowledge by interference and a way of generalizing with respect to the significance of specific findings. The intra‐individual variation of hidradenitis was described through classification of specimens taken from patients with multiple simultaneous or consecutive excisions. A total of 51 specimens from 11 patients were examined; of these 30 were from synchronous biopsies, and 21 from consecutive biopsies (range 2 months to 6 years). The majority of specimens (44/51) contained poral occlusion, sinus tracts or cysts. This pattern was present in 50–85% of the specimens from any given patient with hidradenitis. No primary apocrine involvement was seen. Fibrosis occurred often (33/51 specimens), and eccrine involvement was seen more often than apocrine involvement (10 vs 7 specimens). The homogeneous histology of hidradenitis supports its reclassification as a follicular disease. The reproducibility of the findings further suggests that the changes are specific and that hidradenitis is therefore a definite disease entity within the spectrum of follicular diseases. Additional functional studies may help classify hidradenitis more precisely in relation to other follicular diseases.
Expression of the ubiquitin carboxyl‐terminal hydrolase PGP 9.5 in axons following spinal cord compression trauma. An immunohistochemical study in the rat
Authors: LI GUI LIN , FAROOQUE MOHAMMAD , HOLTZ ANDERS , OLSSON YNGVE
Published: August 2009

Protein gene product 9.5 (PGP 9.5) is a neuron‐specific protein which acts as a ubiquitin carboxylterminal hydrolase. It facilitates the conversion of polyubiquitin to monoubiquitin, which can be reused for another catalytic cycle. Monoubiquitin plays an important role in degrading abnormal and denatured proteins. Previously, we have reported that ubiquitin‐like immunoreactivity is expressed in axonal swellings following compression trauma to the rat thoracic cord. It was characterized by fast occurrence, progressive increase and gradual disappearance over a period of 9 days. The expression of PGP 9.5 has now been studied in the same material. Control rats showed a weak PGP 9.5 immunoreactivity in the nerve cell bodies of the cord. Except for the corticospinal tracts, the axons of other longitudinal tracts were weakly stained. Accumulation of PGP 9.5 immunoreactivity occurred in expanded axons at the site of compression already 4 h after trauma. They became more frequent in number 1 and 4 days after injury and remained so over the entire observation period of 9 days. The labelled axons were randomly distributed in the longitudinal tracts, but were never found in the corticospinal tracts. The extent of immunoreactivity was related to the degree of impact on the cord. Compression injury thus induces accumulation of both ubiquitin and PGP 9.5 immunoreactivity in axonal expansions. The injured axons may have a mechanism for degradation of proteins by the ubiquitin‐mediated proteolytic pathway and another mechanism for effective ubiquitin regenerative cycling by the action of PGP 9.5.
Mechanisms involved in the early interaction between HeLa cells, platelets and endothelial cells in vitro under the influence of thrombin
Authors: KLEMENTSEN BEATE , JØRGENSEN LEIF
Published: August 2009

The aim of the study was to obtain more information about the mechanisms involved in the initial adhesion of tumour cells to endothelial cells during metastasis. In a previous paper, we found that addition of both platelets and thrombin increased the adhesion of tumour cells to cultured endothelial cells within 15 min, compared to when either one or both of the ingredients were absent. In the present study, HeLa cells, prelabelled with radioactive 51Cr, human platelets, and thrombin, were added to the medium in dishes of endothelial cells. The dishes were then shaken for 15 min at 37°C. Scanning and transmission electron micrographs showed HeLa cells adhering to the endothelium either together with platelets or without them. In other experiments, the endothelium was pretreated for 30 min with either of the following: 0.5 mM or 0.1 mM acetylsalicylic acid (ASA); 0.5 rnM or 0.1 mM Na‐salicylate (NaS). Pretreatment of the endothelium with 0.5 mM ASA significantly increased the percentage of adherent tumour cells, while 0.1 mM ASA and the two concentrations of NaS caused only minor changes. In addition, the ASA‐treatment caused more HeLa cells to adhere without platelets while NaS‐treatment caused more HeLa cells to adhere together with platelets. Release of 51Cr from HeLa cells during the experimental period was also measured; the addition of thrombin and platelets did not change the 51Cr release significantly. In separate experiments, HeLa cells and platelets were mixed without the presence of endothelial cells. Transmission electron micrographs showed that in the absence of thrombin, mixed HeLa cells and platelets did not react with each other; when thrombin was added they formed co‐aggregates. In conclusion, we show that in our experimental model HeLa cells adhere to the endothelium in two ways, both with and without platelets. The production of prostacyclin in the endothelial cells has an inhibitory effect on tumour cell adhesion. Without thrombin, the HeLa cells are not capable of activating platelets.
Effect of adenovirus 2 on cellular gene activation in blood‐derived monocytes and macrophages
Authors: KRISTOFFERSEN A. K. , SINDRE H. , MÁNDI Y. , ROLLAG H. , DEGRÉ M.
Published: August 2009

We have investigated the effect of adenovirus 2 (Ad2) infection on human monocytes and monocytederived macrophages with regard to expression of TNF‐α and IL‐1β. In monocytes, the virus was bound to the surface without being internalized. On the other hand, Ad2 was internalized by macrophages. No virus replication and no transcription of the Ad2 early genes was observed in either of the cells. Ad2 infection induced transient increase in the mRNA levels for TNF‐α andIL‐1β in both monocytes and in macrophages, although the kinetics of the transcription was slightly different. The production of both cytokines, measured by ELISA tests, was enhanced in monocytes. In macrophages, a slight enhancement of TNF‐α production was seen, whereas IL‐1β was not detected. The data indicate that cellular genes might be activated by Ad2 virus infection in nonpermissive cells where no viral gene products could be detected.
Transfer of primed CD4+OX40− T lymphocytes induces increased immunity to experimental Salmonella typhimurium infections in rats
Authors: THYGESEN PETER , CHRISTENSEN HENNING BJØRN , HOUGEN HANS PETTER , RYGAARD JØRGEN
Published: August 2009

The protective effect of primed CD4 T cells against a lethal dose of Salmonella typhimurium was studied in Lewis rats. Primed CD4 T cells were obtained by inoculating Lewis rats with a non‐lethal dose of S. typhimurium. Four weeks after the infection, spleen non‐adherent mononuclear cells were isolated. The cells were separated according to their expression of CD4 and the OX40 antigen by FACS. OX40+ and OX40− CD4+ T‐cell subpopulations were together with unsorted CD4+ T cells transferred to untreated rats 24 h prior to infection with S. typhimurium. Transfer of either unsorted CD4+ T cells or CD4+ T cells sorted into OX40− or OX40− subpopulations significantly increased animal survival compared to controls. Animals receiving OX40+CD4+ T cells did not differ significantly in survival probability from those receiving unsorted CD4+ T cells. However, animals receiving OX40−CD4+ T cells had a significantly better survival compared to animals given unsorted CD4+ T cells. It is concluded that OX40−CD4+ T cells can induce significant protection against S. typhimurium infections in rats. This is most likely due to the fact that the OX40−CD4+ T‐cell population contains a significant number of antigen‐specific memory T cells that have returned to a resting state.
Angiogenesis: new aspects relating to its initiation and control
Authors: NORRBY KLAS
Published: August 2009

Angiogenesis, the formation of new microvessels from parent microvessels, involves remodeling the basement membrane and interstitial extracellular matrix (ECM) using degrading proteases produced by the endothelial cells (ECs) and other adjacent cells, and the synthesis of ECM molecules by these cells. Degraded ECM releases previously bound heparin‐binding cytokines (and growth factors) which are able to act as ligands to high‐affinity receptors on various target cells, including ECs. The EC carries receptors for a number of cytokines which are produced by neighboring cells or released from the ECM and which can either induce or suppress the angiogenic phenotype of the EC. ECs are able to synthesize and secrete cytokines with auto‐ and paracrine effects. Angiogenesis, which virtually never occurs physiologically in adult tissues (except in the ovary, the endometrium and the placenta), is essential in wound healing and inflammation. Angiogenesis is, in fact, strictly controlled by a redundancy of pro‐ and antiangiogenic paracrine peptide molecules, some of which have recently been described. The expression and synthesis of two distinct anti‐angiogenic factors is, for example, controlled by the p53 tumor suppressor gene. In certain hypoxic conditions, chronic inflammatory diseases and syndromes, angiogenesis is of pathogenic and prognostic significance. Angiogenesis is, moreover, essential for the growth and metastatic spread of solid tumors. This indicates the potential for developing new therapeutic strategies not only for tumors but also in diseases such as rheumatoid arthritis, psoriasis, liver cirrhosis and diabetic retinopathy. Moreover, the therapeutic induction of angiogenesis in ischemic tissues using recombinant cytokines is also promising for clinical application. In fact, the first successful human gene therapy for stimulating angiogenesis has recently been reported.
Ginseng treatment enhances bacterial clearance and decreases lung pathology in athymic rats with chronic P. aeruginosa pneumonia
Authors: SONG ZHI JUN , JOHANSEN HELLE KROGH , FABER VIGGO , HØIBY NIELS
Published: August 2009

In an athymic rat model of chronic Pseudomonas aeruginosa lung infection mimicking cystic fibrosis (CF), we studied the effects of the Chinese herb ginseng. Rats were treated subcutaneously with ginseng extracts (25 mg/kg) once a day for 10 days after challenge with P. aeruginosa embedded in alginate beads. We found that ginseng treatment significantly reduced bacterial load (p<0.02) and the number of mast cells in the lungs (p<0.01). Furthermore, it decreased the severity of lung pathology (p<0.02) and lowered serum anti‐P. aeruginosa IgM and IgA antibody levels (p<0.004, p<0.04) compared to the control group. The down‐regulated specific humoral immunity in the ginseng‐treated group and the fact that athymic rats have a severely compromised T‐cell‐mediated immune reactivity due to the absence of thymus might suggest an activation of innate immunity after ginseng treatment. Our findings indicate that ginseng treatment increases the resistance of the athymic rats to P. aeruginosa lung infection. We therefore think that ginseng has promising potential as a natural medicine for stimulation of the immune system in CF patients with chronic P. aeruginosa lung infections.
Primary T‐cell lymphoma of the breast with lymphoepithelial lesion
Authors: VASEI MOHAMMAD , KUMAR PERIKALA V. , MALEKHOSSEINI SEYED ALI , AMIRGHOFRAN ZAHRA
Published: August 2009

Fine‐needle aspiration, histomorphologic and immunologic findings in a case of primary T‐cell lymphoma of the breast are reported. The tumor cells were diagnosed as large cell lymphoma with lymphoepithelial lesion and no nuclear multilobulation. No serologic evidence of HTLV‐1 infection was detected. After simple mastectomy, lymph node dissection and chemotherapy, the patient is now doing well, having been followed for 30 months. To our knowledge, this is the first case report of primary T‐cell lymphoma of the breast with prominent lymphoepithelial lesion, no nuclear lobularity, and an indolent clinical course.
The clonal antibody response to Pseudomonas aeruginosa heat shock protein is highly diverse in cystic fibrosis patients
Authors: ULANOVA M. , PETERSEN T. D. , CIOFU O. , JENSEN P. , HAHN‐ZORIC M. , HANSON L. Å. , HØIBY N.
Published: August 2009

The GroEL protein of Pseudomonas aeruginosa belongs to the bacterial 60–65 kDa heat shock protein family. A strong antibody response to GroEL has been found in cystic fibrosis (CF) patients with chronic pulmonary infection caused by P. aeruginosa. Clonotypes of IgG1 and IgG2 antibodies against GroEL were studied in 60 consecutive sera from 18 CF patients with chronic P. aeruginosa infection using isoelectric focusing in combination with affinity immunoblotting. The persistent antigenic stimulation in CF patients with chronic P. aeruginosa infection induced numerous IgG1 and particularly IgG2 antibody clones against GroEL. The appearance of new clones with time reflected the long duration of the chronic infection. A striking addition of new clonotypes during the observation period occurred when a new unrelated bacterium (Burkholderia cepacia) had become established as a cause of the pulmonary infection, or when the P. aeruginosa infection became chronic.
High‐molecular weight IGF‐2 expression in a haemangiopericytoma associated with hypoglycaemia
Authors: HÖÖG A. , NORDQVIST A. C. SANDBERG , HULTING A. L. , FALKMER U. G.
Published: August 2009

Spontaneous hypoglycaemia is usually caused by an insulin‐producing islet‐cell tumour of the pancreas. Rarely, it can be caused by non‐islet cell tumours. Most of the tumours are of mesenchymal type, large, and slowly growing. One representative is haemangiopericytoma (HAP). The present report describes a case of a large recurrent retroperitoneal HAP associated with severe hypoglycaemia. Blood serum insulin and proinsulin concentrations were low. By means of acid‐gel chromatography and dot‐blot techniques, an increased amount of a high‐molecular‐weight IGF‐2 peptide was found. By using antigen retrieval procedures, IGF‐2‐immunoreactive tumour cells were found in specimens of the recent tumour recurrence ‐ but not in the original. When the in situ hybridization technique was used it could be shown that IGF‐2 mRNA labelling had already occurred in the original tumour specimen, 11 years before the onset of hypoglycaemic symptoms. These observations confirm the hypothesized hypoglycaemic effects of high‐molecular‐weight (HMW) IGF‐2, but also point to the presence of a prolonged compensation of this effect. A literature review, based on 17 similar cases of haemangiopericytoma with hypoglycaemia, is presented. Our observation and findings in the literature review support the idea that non‐islet‐cell tumour hypoglycaemia is caused by an overproduction of a HMW IGF‐2 peptide. The insulin‐like effect is mediated via non‐specific binding to the insulin receptors. To anticipate patients at risk of developing this kind of hypoglycaemia, the histopathological investigation should include not only immunohistochemical analyses of the presence of IGF‐2 peptide, but also in situ hybridization of the IGF‐2 mRNA expression.
Cytokine receptor signal transduction through Jak tyrosine kinases and Stat transcription factors
Authors: SILVENNOINEN OLLI , SAHARINEN PIPSA , PAUKKU KIRSI , TAKALUOMA KATI , KOVANEN PANU
Published: August 2009

Cytokines are the principal regulators of cell proliferation and differentiation of hematopoietic cells and these responses are initiated through activation of hematopoietic cytokine receptors. Although the receptor intracellular domains lack any kinase domains, activation of cytokine receptors lead to rapid induction of tyrosine phosphorylation. Recently, cytokine receptors have been shown to associate with and activate members of the cytoplasmic Jak tyrosine kinase family. Activation of Jak kinases leads to phosphorylation of several signaling proteins and thereby couples ligand‐mediated receptor stimulation to activation of intracellular signaling pathways. The best characterized substrates for Jaks are the Stat transcription factors, which are crucial mediators of cytokine‐mediated gene responses, and, particularly, central determinants for the specificity in cytokine responses.
Differential expression of integrins and laminin‐5 in normal oral epithelia
Authors: THORUP ALIS KARABULUT , DABELSTEEN ERIK , SCHOU SØREN , GIL SUSANA G. , CARTER WILLIAM G. , REIBEL JESPER
Published: August 2009

β1 and β4 integrins are receptors on epithelial cells mediating cell‐extracellular matrix adhesion. Furthermore, α2β1 and α3β1 contribute to cell‐cell adhesion. Laminin‐5 in epithelial basement membranes (BMs) is a ligand for α6β4 and α3β1. Expression of different integrins and laminin‐5 was studied in oral epithelium to characterize regional variations in these adhesion molecules. Monoclonal antibodies directed against α2‐α6β1/α6β4 and laminin‐5 were examined in cryopreserved biopsies of normal mucosa by immunohistochemistry. Laminin‐5 was expressed as a line along the BMs. The junctional epithelium showed a unique phenotype: Laminin‐5 was detected in the internal BM at the tooth surface and in the external BM, where excessive laminin‐5 was seen in the stroma. α6β4 was expressed in all cells of the junctional epithelium. Integrins α4β1 and α5β1 were not detected in the epithelia, whereas α2β1 and α3β1 showed differential expression. Epithelia with well‐developed rete pegs and connective tissue papillae showed polarized α3β1 expression along the BM in the rete pegs, in contrast to negative expression at the tips of the connective tissue papillae. A variation in the suprabasal distribution of α2β1 and α3β1 was observed between epithelia from different regions. α2β1 and α3β1 were detected in basal/parabasal cells in keratinized epithelia, whereas there was increased suprabasal expression in nonkeratinized mucosa. These results indicate inhomogeneity in the basal cell population of oral squamous epithelia and differential expression of integrins, which may reflect differences in the underlying stroma. Laminin‐5 deposits in the stroma underneath the junctional epithelium may indicate subclinical gingival inflammation.
Detection of serum interferon‐α by dissociation‐enhanced lanthanide fluoroimmunoassay
Authors: RÖNNBLOM L. E. , PERERS A. , VALLIN H. SVENSSON , ERIKSSON I. , ÖSTERLIND A. , CEDERBLAD B. , ALM G.
Published: August 2009

A sensitive dissociation‐enhanced lanthanide fluoroimmunoassay (DELFIA) was evaluated for ability to detect interferon‐α (IFN‐α) in serum of patients with acute infectious disease of less than one week's duration and a fever of >38°C. None of 36 patients with confirmed or probable bacterial disease was IFN‐α positive. In contrast, 13/26 patients with viral infections had detectable levels of IFN‐α in serum, all clearly positive (≥10 U/ml). The IFN‐α positive serum samples were obtained early after onset of clinical disease, after a mean of 2.4 days. The IFN‐α positive samples were obtained from 10 of the 12 patients with influenza or flu‐like infection, and 3 of the 5 patients with varicella or herpes zoster. The IFN‐α negative patients with viral disease (n=9) included five patients with mononucleosis. The DELFIA should be useful in further studies of the value of IFN‐α determinations in the identification of acute viral infections.
Expression of GLUT1 in stratified squamous epithelia and oral carcinoma from humans and rats
Authors: VOLDSTEDLUND MARIANNE , DABELSTEEN ERIK
Published: August 2009

Most cells express facilitative glucose transporters. Four isoforms (GLUT1‐4) transporting D‐glucose across the plasma membrane show a specific tissue distribution, which is the basis for tissue‐specific patterns in glucose metabolism. GLUT1 is expressed at high levels in tissue barriers such as the blood‐brain barrier, and this isoform has been suggested as an indicator of such barriers. GLUT1 has been found in basal layers of human epidermis where no such tissue barrier is present. To further clarify these issues, we examined the distribution of GLUT1 and GLUT4 in skin, different types of oral mucosa from rat and man, and a human oral careinoma by indirect immunofluorescence microscopy. The results showed that GLUT1 was expressed in the basal and parabasal layers of the different stratified squamous epithelia, with some variations between keratinized and non‐ keratinized subtypes. GLUT1 was also expressed in ductal‐ and myoepithelial cells of minor salivary glands and perineural sheath located in the lamina propra, and furthermore in the cells of an oral careinoma. GLUT4 was not expressed in any of the tissues examined. This distribution of GLUT1 does not fit with the idea of GLUT1 as a general indicator of tissue barriers. In contrast, our results support the prevailing, but limited knowledge of glucose metabolism in squamous stratified epithelia, a metabolism believed to depend mostly on glycolysis, especially in the basal layers. High‐level expression seemed to be confined to keratinocytes without glycogen stores.
Distribution of adhesion molecules on HeLa cells, platelets and endothelium in an in vitro model mimicking the early phase of metastasis
Authors: KLEMENTSEN BEATE , JØORGENSEN LEIF
Published: August 2009

The aim of the present study was to obtain information about the distribution of various adhesion molecules within and on the surface of HeLa cells, platelets and endothelial cells in an in vitro model mimicking the early phase of metastasis. Suspensions of HeLa cells and human platelets, added to a medium of cultured human umbilical‐vein endothelial cells, were stimulated by the addition of thrombin. Hirudin was added before thrombin in some experiments, and in other experiments the endothelium was pretreated with 0.5 mM acetylsalicylic acid (ASA). The distribution of platelet‐endothelial cell adhesion molecule (PECAM), P‐selectin, von Willebrand factor (vWf), fibrinogen (FG) and thrombospondin (TSP) was investigated on fixed material from the three experimental settings by using an immunogold electron‐microscopic technique on frozen thin sections. Cells that had not been exposed to thrombin or any other type of stimulation were used as controls. PECAM was the only adhesion molecule detected on HeLa cells. It outlined the membrane on tumour cells that were not adherent to platelets in both basic and hirudin experiments. However, tumour cells in close proximity to activated platelets were unlabelled. In contrast, PECAM was detected on both platelets and endothelium in all experimental settings and in controls. P‐selectin was only demonstrable on platelets in basic experiments. vWf was found both in endothelium and in platelets in controls and in all experimental settings. FG and TSP were found on platelets only, in a manner similar to that seen with vWf. Thus, among the adhesive factors examined in our experimental model, PECAM is the only one demonstrated on HeLa cells. This suggests that PECAM on tumour cells may play a role as adhesion molecule in the early stage of metastasis. P‐selectin, vWf, FG and TSP were also consistently expressed. Therefore, these factors may contribute to the adhesive reactions involved in early metastasis.
Observer variability in histological malignancy grading of adenoid cystic carcinomas
Authors: THERKILDSEN MARIANNE HAMILTON , REIBEL JESPER , SCHIØODT TORBEN
Published: August 2009

The value of malignancy grading of adenoid cystic carcinomas (ACC) is controversial. Some studies have shown that tumours with a solid growth component have a rapid fatal course, compared to tumours without a solid growth component, in which recurrences develop even many years after initial treatment. Other studies have failed to correlate growth patterns with clinical course. No universally accepted grading system exists and no reproducibility studies of the existing grading systems have been performed. The aim of this study was to examine the reproducibility of grading based on semi‐quantitative assessment of the solid growth pattern in ACC. Two different grading systems were assessed by 3 observers on a material of 59 ACC. Interobserver agreement was evaluated using the kappa statistic. The reproducibility of grading was poor, except for the category “solid component constituting 50% or more of the tumour” (kappa=0.52). It is concluded that quantitative methods are necessary if grading is to be used in prognostic evaluation of ACC. The rarity of the tumours, however, combined with difficulties in diagnosis will impede such investigations unless multicentre studies are undertaken.
Microbiology of semen specimens from males attending a fertility clinic
Authors: KJÆRGAARD N. , KRISTENSEN B. , HANSEN E. S. , FARHOLT S. , SCHØONHEYDER H. C. , ULDBJERG N. , MADSEN H.
Published: August 2009

The relationship between semen quality, pyospermia and bacteriology was studied in 201 semen specimens from male patients attending a fertility clinic. Semen quality parameters were within normal limits in 115 (57%) patients, slightly reduced in 60 (30%), and 26 (13%) had findings indicating reduced fertility. Twelve patients (6%) had pyospermia. In 182 patients, 552 microorganisms were detected, including Enterobacteriaceae (2.8%), Gardnerella vaginalis (9.6%), Chlamydia trachomatis (1.6%), Mycoplasma genitalium (0.9%), and Ureaplasma urealyticum (11.8%). Semen quality was neither related to occurrence of microorganisms nor pyospermia. However, pyospermia was associated with simultaneous growth of Gardnerella vaginalis and Ureaplasma urealyticum. The exact nature of this association could not be ascertained, in as far as the males were not questioned about urethritis symptoms.
Three‐dimensional estimation of the glandular volume, and of the number and volume of epithelial cells in two glands from the antral mucosa of five healthy volunteers
Authors: URIBE ANDRÉES , GUNDERSEN HANS JØORGEN G.
Published: August 2009

Specimens of antral mucosa were taken from five healthy volunteers and processed for microscopic evaluation. Consecutive 50‐μum‐thick sections were cut to estimate the volume of two antral glands. Two glands in each section were followed throughout by projecting their profiles from two microscopes mounted in parallel. The glandular volume was estimated using Cavalieri's principle. The mean volume of epithelial cells was estimated by systematic random sampling of the sections with an optical disector of known sample volume. The total number of cells per gland was calculated after determination of the volume of the glands and the mean volume of the epithelial cells. The mean volume of the antral glands was 13.6±1.67 106μum3, whilst the mean volume of the epithelial cells was 1256±240 μum3. The total number of epithelial cells per gland was 11216±1104. In conclusion, using stereological methods, the total number of cells as well as the cell volume and the volume of antral glands can be determined in routine biopsy specimens of human stomach provided that the total depth of the mucosa is present in the section.
The cell cycle in breast cancer
Authors: LANDBERG GÖORAN , ROOS GÖORAN
Published: August 2009

Breast cancer is a heterogeneous disease regarding morphology, invasive behavior, metastatic capacity, hormone receptor expression and clinical outcome. For prediction of prognosis, tumor cell kinetics is an important feature, traditionally evaluated by estimation of cell growth‐associated parameters such as mitotic index, S‐phase fraction and expression of proliferation coupled proteins, for example proliferating cell nuclear antigen (PCNA) and Ki‐67 antigen. Recent data indicate that deregulation of the cell cycle can occur at different levels in cancer and that the “deregulation pattern” can be of clinical significance. In the present overview we give a short description of approaches used for cell proliferation assessments, whereafter more recent data on cell cycle deregulation are discussed. Alterations of importance in breast cancer include overexpression of cyclins D1 and E, down‐regulation of cyclindependent kinase inhibitors, such as p16, and inactivation of the retinoblastoma and p53 tumor suppressor proteins.