bluuebunny/crossref_metadata_2025 huggingface dataset:
Cell proliferation rate and tumor volume in human osteosarcoma during exposure to methotrexate
Authors: Smeds STAFFAN , Walz THOMAS , Blomquist LENA , Larsson SVEN‐ERIC
Published: August 2009

The growth inhibitory effect of methotrexate (MTX) on osteosarcoma cells was studied in dysthymic nude mice bearing tumor transplants obtained from a patient before (PRE‐CHEM) and after (POST‐CHEM) preoperative chemotherapy for osteosarcoma of the distal femur. Cell proliferation was analyzed by autoradiographic evaluation of the fraction of labeled cells after continuous administration of 3H‐thymidine for seven days. Histomorphometric analysis of the tissue distribution of cells in the partly ossified tumors was performed. The PRE‐CHEM sarcoma transplants showed a significant reduction of labeled interphases from 52 to 1.7 percent upon daily MTX treatment of the mice as compared to controls. In contrast, MTX treatment did not inhibit cell proliferation in the POST‐CHEM tumor transplants in which approximately 70 percent of the cells were labeled. Tumor volume increased by 65 and 54 percent in the MTX‐treated PRE‐ and POST‐CHEM groups, respectively. During the same eight‐day period, control transplant volume increased by 30 percent (PRE‐CHEM) and 20 percent (POST‐CHEM). Tumor cell densities in the MTX‐treated groups were reduced by a factor of approximately 11 in the PRE‐CHEM transplants and by a factor of approximately 1.5 in the POST‐CHEM transplants. The results show that in this patient the osteosarcoma cells had changed their responsiveness to MTX during the preoperative chemotherapy period. In both the MTX‐sensitive and non‐sensitive tumor lines, exposure to MTX induced increased tumor volume by increasing the extra cellular matrix volume, irrespective of the neoplastic cell proliferation rate. This effect of MTX was most pronounced in the MTX‐sensitive tumor line. These results indicate that in the clinical situation it is difficult to judge the response to chemotherapy even from morphologic parameters.
Association between keratin staining patterns and the structural and functional aspects of palatine tonsil epithelium
Authors: Reibel JESPER , SØRensen CHRISTIAN HJORT
Published: August 2009

The keratin composition of stratified squamous epithelia has a complex pattern, which varies in different regions and as a result of pathological developments. The exact factors responsible for the characteristic keratin composition in a given epithelium are unknown. However, the environment, including factors from the connective tissue, is known to influence epithelial morphology and keratin composition. We here report that the reticulated squamous epithelium of the crypts of palatine tonsils shows an extensive staining for keratins 5 and 19 in basal as well as suprabasal cells, in contrast to neighbouring non‐reticulated crypt epithelium and the epithelium at the tonsillar surface, in which staining is restricted to basal cells. The reticulation of the crypt epithelium is thought to be initiated by infiltration of immune‐related cells in a preexistent non‐reticulated epithelium. The extensive staining for keratins 5 and 19 in reticulated crypt epithelium correlates with the presence of numerous immune system‐related cells and marked expression of intercellular adhesion molecule‐1 (ICAM‐1), thought to be involved in inflammatory and immunological responses. The results suggest that the massive lymphocytic traffic in the reticulated crypt epithelium and the overall distinct immune environment are responsible for the unique keratin staining pattern observed.
Synergy and cumulated killing effect of the penems FCE 22101 and FCE 25199 in combination with gentamicin against bacteria isolated from septicaemia
Authors: Bergholm A. M. , Dornbusch K.
Published: August 2009

Blood isolates of Enteroeoecus faecalis, Streptococcus sanguis, Staphylococcus aureus, E.coli and Klebsiella oxytoca were tested for their synergistic and cumulated killing effect (CKE) with the new penems FCE 22101 or FCE 25199 in combination with gentamicin. The tissue cage model in rabbits was used to study the CKE in vivo after antibiotic treatment of the bacteria in vitro. Synergy was observed within two to seven h with all isolates in early logarithmic phase, except with S. aureus, which was rapidly killed by the penems alone. After one h treatment with the antibiotic combinations in vitro, a CKE was demonstrated for up to six h both in vitro and in vivo. The magnitude of the CKE differed between strains and in vitro vs. in vivo.
Morphology Of Pseudomonas aeruginosa phages from the sputum of cystic fibrosis patients and from the phage typing set
Authors: Ojeniyi B. , Birch‐Andersen A. , Mansa B. , Rosdahl V. T. , HØIby N.
Published: August 2009

Sixteen phage suspensions isolated from the sputum of sixteen cystic fibrosis patients and five phages from the present phage typing set were studied by electron microscopy. All sputum samples contained at least one type of bacteriophage (range: 1–4) which could be classified by the morphology and dimensions of the virion. All phages isolated from sputum as well as the four typing phages were tailed phages. The clinical phages belonged either to the Myoviridae, Siphoviridae or Podoviridae family. The four typing phages belonged to the Myoviridae family. The detection of the presence of tailed phages in sputum further supports the prevailing theory that phages play a role in the phenotypical change of Pseudomonas aeruginosa during the chronic lung infection of cystic fibrosis patients, since only tailed phages are known to be temporate and thus mediate transduction and conversion.
Expression of blood group‐related carbohydrate antigens in normal human pancreatic tissue
Authors: Philipsen ELSE K. , JØRgensen MOGENS , Dabelsteen ERIK
Published: August 2009

The expression of type 1, 2 and 3 chain carbohydrate structures in 15 normal pancreata was investigated by immunohistochemical methods using well‐defined monoclonal antibodies. Surgical biopsies of pancreata were obtained from kidney donors while the organs were still perfused. Type 1 chain structures were abundantly expressed including monosialylated(ms)‐ and disialylated(ds)‐Lea antigens, which have previously been associated with cancer. Type 2 chain structures were represented by H and Ley antigens and to a lesser extent by the precursor structure N‐acetyllactosamine, whereas Lex dimeric Lex, and ms‐Lex were only sporadically observed, in contrast to fetal pancreatic tissue, in which Lex has been found to be abundantly expressed. H chain 3 antigen was found in nearly all specimens, whereas precursor structures Tn, sial‐Tn and T antigens were absent. Desialylation unmasked the T antigen in all specimens. Absence/masking of Tn, T and related antigens is of special interest, since these antigens are associated with tumor development in other tissues, and may be of importance in pancreatic cancer diagnostics in the future.
A freeze‐fracture study of the perineurium in normal and protein‐deprived rats
Authors: Beamish N. G. , Stolinski C. , Thomas P. K. , King R. H. M. , Oldfors A.
Published: August 2009

Observations have been made using the freeze‐fracture replication technique on the perineurium of normal and protein‐deprived rats in which its permeability barrier function is known to be deficient. The perineurial cells of young normal rats possessed belt‐like tight junctions (zonulae occludentes) at the borders and maculae occludentes at sites remote from their borders. In older rats, the zonulae occludentes were more prominent and the maculae occludentes relatively less frequent. No abnormalities were detected in the tight junctions of young rats with early induction of protein deficiency but this may have been related to sampling problems. In older severely protein‐deficient animals, although many of the tight junctions were normal, some were abnormal and contained focal regions of dispersed strands. The density of caveolae in the surface membrane of the perineurial cells of older rats with severe protein deficiency was significantly greater than in the control animals. This provides support for the view that the pinocytotic‐like vesicles of perineurial cells are involved in transport of substances across the cells. The increased numbers of caveolae in the protein deficient rats may reflect increased transcellular traffic. There were considerable differences in the density of P‐face IMPs between the different perineurial lamellae, but the results did not allow a decision to be made as to whether there was a polarization of the cells between their endoneurial and epineurial aspects. No differences were detected in the density of P‐face IMPs between the young control and protein‐deprived rats. In the perineurium of the older rats with protein deficiency, IMP density was significantly greater in the E face than in the controls but not different in the P face. The delay in the development of enzymatic activity in the perineurium of protein‐deficient rats that has been demonstrated histochemically is therefore not paralleled by a reduction in IMPs.
Evaluation of a direct fluorescent antibody test for detection of Chlamydia trachomatis in endocervical specimens
Authors: Dereli DENIZ , Ertem EKIN , Serter DEMIR , YÜCe KEMAL
Published: August 2009

A total of 160 endocervical specimens collected from 72 symptomatic and 82 asymptomatic women attending a gynecology outpatient clinic were investigated for genital Chlamydia trachomatis infection by the use of tissue culture and DFA test. The infection rate was 42% for symptomatic and 23% for asymptomatic patient groups. The sensitivity rates of the DFA test in the symptomatic and asymptomatic groups were 84% and 75%), while the specificity rates were 89% and 95%, respectively. The DFA test had an overall sensitivity of 80% and specificity of 93%. There was 90% agreement between the two techniques. Therefore, DFA is recommended as an alternative to tissue culture where laboratory facilities are limited and genital chlamydial infections are highly prevalent.
Granulocyte functions and Neisseria meningitidis: influence of properdin‐deficient serum
Authors: SÖDerstrÖM CLAES , Braconier JEAN HENRIK , SjÖHolm ANDERS G. , Thuresson BRITT
Published: August 2009

Granulocyte‐mediated reactions such as opsonization, chemotaxis, and release of granulocyte myeloperoxidase and lactoferrin were studied in properdin‐deficient and normal human serum incubated with serogroup A and W‐135 meningococci. There were no differences between the sera when serogroup A meningococci were studied. Opsonic and chemotactic activity were impaired against serogroup W‐135 meningococci in properdin‐deficient serum. Restitution with properdin restored both activities. We found similar release of myeloperoxidase and lactoferrin from granulocytes challenged with serogroup A or W‐135 meningococci in either sera. These findings are in accordance with the clinical observations of meningococcal infections caused by serogroup W‐135 in properdin‐deficient patients as well as the absence of infections caused by serogroup A meningococci.
Monoclonal antibodies against Yersinia enterocolitica common antigen produced by immunization with immunoprecipitates
Authors: Bagger YU ZHAO
Published: August 2009

Crossed immunoelectrophoresis was applied to purify Y. enterocolitica common antigen by precipitation with monospecific rabbit anti‐P. aeruginosa CA antibody. Monoclonal antibodies against Y. enterocolitica CA were then raised by immunization of mice with these immunoprecipitates. This method provides the possibility of producing a panel of anti‐CA monoclonal antibodies from a large number of bacterial species.
Radiometric and conventional drug susceptibility testing of Mycobacterium tuberculosis
Authors: Hoel TERJE , Eng JAN
Published: August 2009

One hundred and four clinical isolates of M. tuberculosis were susceptibility tested by the radiometric method (RAD) using the BACTEC® system in parallel with a conventional modified proportion method (CON). In the latter, the strains were tested against four concentrations of drugs in Lowen‐stein‐Jensen medium (isoniazid (INH), streptomycin (SM) and ethambutol (EMB)) or 7H10 agar medium (rifampicin (RIF)) and reported as “sensitive”, “intermediate” or “resistant” from the minimum inhibitory concentrations observed. The radiometric results were classified in the same three groups in accordance with the BACTEC® methodology. The overall agreement between the results obtained by the two methods was 97.4% (INH 95.2%, EMB 96.2%, SM 98.1% and RIF 100%). In addition, the agreement between RAD and each of the drug concentration steps employed in CON was examined and the results discussed in relation to the established critical concentrations of the drugs. The BACTEC® technique was found to be a rapid and convenient method for routine use.
Immunohistochemical localization of coagulation, fibrinolytic and antifibrinolytic markers in adenocarcinoma of the lung
Authors: Nakstad BRITT , Lyberg TORSTEIN
Published: August 2009

Extravascular coagulation and fibrinolysis are intimately involved in and modulate cancer cell growth, invasion and metastasis. Samples from resection specimens of patients with primary lung cancer (adenocarcinomas) were tested with monoclonal (MAb) and polyclonal (PAb) antibodies against various factors of the coagulation or fibrinolysis systems, or against antigens of inflammatory or proliferating cells. MAb Ki‐67 specific to nuclear antigens of proliferating cells showed a distinct but variable staining of cell nuclei throughout the tumor tissue. Nests of tumor tissue stained with cytokeratin‐specific antibodies (PKK1), whereas other parts were negative. Fibrin(ogen) and fibronectin were found throughout the tumor tissue stroma and in the alveolar lining, and the most densely stained areas were at the transition zone between normal and tumor tissue. Fibrinolytic system components like tissue plasminogen activators (t‐PA), and urokinase (u‐PA), and their inhibitors PAI‐1 and PAI‐2 were all studied. All specimens were negative for t‐PA (except endothelial linings), whereas urokinase‐specific antibodies stained loosely packed tumor cells and macrophages within the tumor stromal tissue and alveolar septa. Both PAI‐1 and PAI‐2 were most prominently expressed within interstitial and alveolar macrophages. A weaker staining of tumor tissue cells was demonstrated. Inflammatory cells like macrophages and T lymphocytes were located in aggregates or diffusely spread within tumor stromal tissue. The inflammatory reaction was most intense at the border between normal lung and tumor tissue.
Reduction of diabetes incidence in NOD mice by neonatal glucose treatment
Authors: Bock T. , KjÉR T. W. , JØRgensen M. , Josefsen K. , Rygaard J. , Buschard K.
Published: August 2009

The aim of this study was to investigate whether neonatal glucose treatment influences the incidence of diabetes in NOD mice. Thirty‐nine NOD mice (19 males, 20 females) were treated with 8 g glucose/ kg BW/day administered by subcutaneous injections twice a day for the first six days of life. Thirty‐six untreated NOD mice (20 males, 16 females) served as a control group. In the glucose‐treated group, 33% became diabetic compared with 58% in the control group (X2= 5.3, p = 0.021). Among the glucose‐treated males, 16% became diabetic compared with 50% of the untreated males (X2= 5.5, p = 0.019), whereas 50% of the glucose‐treated females became diabetic compared with 69% of the untreated females (X2= 1.1, NS). We conclude that neonatal glucose treatment can reduce the diabetes incidence in NOD mice. These results could have implications for the prevention of type 1 diabetes mellitus in humans.
Quantification of acid mucins in the descending colon of rats having simultaneously growing colonic tumors
Authors: Rubio CARLOS A. , Rivera FRANCISCO
Published: August 2009

The acid mucins contained in goblet cells of the descending colon of 34 male Sprague‐Dawley rats were histochemically labeled by Alcian blue pH 2.5 and quantified in an image analyzer (Cortex Controller). Twenty‐two of these 34 rats were treated with 1,2‐dimethylhydrazine (DMH) suspended in EDTA solution as a stabilizing agent and the remaining 12 rats with EDTA only. Of the 22 DMH‐treated rats, 11 had concomitantly an adenocarcinoma elsewhere in the colon and the remaining 11 rats had no colonic tumors despite DMH treatment. The results indicated that Alcian blue‐positive areas occupied 34.5% of the mucosa of the descending colon in tumor‐bearing rats, and 35.2% in non‐tumor‐bearing DMH‐treated rats. For EDTA‐treated rats the percentage of mucosa occupied by Alcian blue‐positive cells was 48.1%. The difference between DMH‐treated rats (with or without tumors) and EDTA‐treated rats was significant (p < 0.001). These results suggest that the decrease of Alcian blue areas is related to the protracted treatment with DMH. Whether the decrease in acid mucins is induced by the carcinogen per se or whether it represents a true biochemical premalignant change at the cytoplasmic level remains to be elucidated.
Helicobacter‐associated duodenitis and gastric metaplasia in duodenal ulcer patients
Authors: Madsen JAN ERIK , Vetvik KÅRE , Aase STEINAR
Published: August 2009

Biopsy specimens were taken from the duodenal bulb and the distal duodenum in 45 duodenal ulcer patients before and after treatment with histamine‐2 antagonists, prostaglandin analogues or antacids. After four weeks of treatment, the ulcer had healed in 31 patients. The treatment did not lead to a reduced frequency of helicobacter‐associated duodenitis or gastric metaplasia of the duodenal epithelium. We found gastric metaplasia in 52.3% of all biopsy specimens from the duodenal bulb, chronic active duodenitis in 71.9% and helicobacter‐like structures in 15.9%. The helicobacter organisms were found only in areas of gastric metaplasia, and an accompanying chronic active duodenitis was found in 94.1%. In the distal duodenum, we observed chronic active duodenitis in 15.0% of the specimens. Here the inflammation was not associated with gastric metaplasia or helicobacter‐like structures. These observations support the hypothesis that Helicobacter pylori colonizes the duodenal mucosa only in areas of gastric metaplasia, and that such colonization may lead to an active duodenitis.
Disseminated infection of herpes simplex virus with fulminant hepatitis in a healthy adult
Authors: Miyazaki YOSHITAKA , Akizuki SHIN'ICHIRO , Sakaoka HIROSHI , Yamamoto SHUNSUKE , Terao HIDEO
Published: August 2009

An autopsy case of fulminant hepatitis caused by herpes simplex virus type 1 in a healthy adult is presented. The clinical course was characterized by hepatic failure, disseminated intravascular coagulation and acute renal failure. Many small ulcerations were present in the tongue and tonsils, and there were foci of hemorrhagic necrosis in the liver. Herpes simplex viral antigen was identified in the liver, tonsils, spleen, tongue, pharynx, larynx, esophagus, stomach, intestine, adrenal glands, and lymph nodes with immunohistochemical staining using antibodies to herpes simplex virus type 1. The electron microscopic examination revealed many virions in the hepatocytes. Herpes simplex virus was isolated from the liver, and viral DNA, which had some distinctive features of herpes simplex virus type 1, was examined. We discuss possible reasons for this opportunistic infection occurring in a healthy adult.
Parietal cell carcinoma of the stomach
Authors: Rychterova VLASTA , HÄGerstrand INGA
Published: August 2009

Two cases of parietal cell carcinoma are reported and compared with seven cases previously described. Eight of nine patients have been male. The tumours grow mainly outside the mucosa and can macro‐and microscopically be misinterpreted as leiomyoblastomas or lymphomas. The survival, also with metastases, is long. The proper diagnosis requires ultrastructural investigation.
Temporal artery morphology and morphometry in giant cell arteritis
Authors: Nordborg E. , Bengtsson B. Å. , Nordborg C.
Published: August 2009

Paraffin sections and more than 7,000 plastic cross‐sections of temporal arteries from 27 patients with a clinical diagnosis of polymyalgia rheumatica (PMR), 16 patients with a clinical diagnosis of temporal arteritis (TA) and 18 age‐ and sex‐matched postmortem controls were studied using light microscopy. A new method was developed to permit a morphometric comparison between biopsies and autopsy specimens. Two stages of inflammation were discerned in TA. In atrophic arterial segments there was a focal, foreign‐body, giant‐cell reaction to the calcified internal elastic membrane (IEM) with a spatially correlated, mononuclear cell infiltration. Isolated giant cells were also found to attack the IEM in these cases. The majority of the biopsies displayed a different picture with a diffuse macrophage attack on media and intima with numerous and apparently macrophage‐derived giant cells, which did not attack calcifications. The latter arteries were significantly widened (p < 0.02), which indicates that this phase is the later one. Non‐inflamed segments of PMR vessels displayed a significant, non‐reactive media atrophy compared with controls (p < 0.03) and their IEM calcifications were significantly larger (p < 0.02). The circumference was smaller in atrophic PMR arteries than in inflamed TA arteries (p < 0.006), which contradicts post‐inflammatory scarring.
Gross examination of musculoskeletal sarcomas Estimation of tumour volume and sampling for unbiased morphometry
Authors: Jensen OLAF MYHRE
Published: August 2009

A method for handling and gross examination of specimens from musculoskeletal sarcomas is described. The method, which can be modified to relate to modern, preoperative tumour imaging, allows an accurate estimation of tumour volume and a systematic random sampling for morphometry, which for instance permits the unbiased estimation of tumour necrosis, cellularity and mitotic index. Furthermore, sampling can be performed in such a way that stereological parameters (for the estimation of nuclear size and pleomorphism) based on ‘vertical sections’ can be measured. The method in no way prohibits routine sampling, for instance from specimen margins and specific areas of interest within the tumour, and with a little practice does not take much extra time.
Effects of alloxan and reducing agents on macrophages in culture
Authors: Zhang HONG , Zdolsek JOHANN M. , Brunk ULF T.
Published: August 2009

The diabetogenic effect of the quinonoid compound alloxan is not understood in detail although it supposedly involves reactions mediated by alloxan and oxygen radicals. These reactive species may form extra‐ or intracellular‐ and cause cell damage through a variety of complex interactions with several macromolecules. The purpose of this study was to elucidate early (≤ 60 min) effects of alloxan and reducing agents (cysteine and ascorbic acid) on cultured macrophages, as assayed by the trypan blue dye exclusion test and the sensitive fluorescein diacetate and propidium iodide (FDA/PI) double staining technique. During the reactions between alloxan and reducing agents, oxygen was consumed as a sign of superoxide anion radical formation. When alloxan alone was added to two different culture media without serum, oxygen was still consumed, indicating formation of oxygen radicals due to the occurrence of reducing substances in cell culture media. This finding demonstrated the necessity of performing further studies in solutions without reducing capacity, e.g. in phosphate‐buffered saline. The experiments showed that exposure of normal and malignant macrophages to alloxan and reducing substances resulted in rapidly occurring plasma membrane damage and ensuing cell death. Separate addition of catalase, desferrioxamine or superoxide dismutase resulted in evident, slight and no protection, respectively. The combinations of (i) catalase and desferrioxamine, and (ii) catalase, desferrioxamine and superoxide dismutase, however, inhibited cell damage in a pronounced and complete way, respectively. The results are interpreted as indicating cell damage due to the extracellular formation of hydrogen peroxide and hydroxyl radicals. The latter in close proximity to the cells and acting on the plasma membrane, while the former, after diffusing into the cell, may have several intracellular targets. The FDA/PI technique proved its value as a quantifiable method for the evaluation not only of cell death but also of cell damage with computer‐based fluorometry.
Mobiluncus species in bacterial vaginosis: aspects of pathogenesis
Authors: Moi H. , Fredlund H. , TÖRnqvist E. , Danielsson D.
Published: August 2009

Mobiluncus is an anaerobic motile rod associated with bacterial vaginosis. In this work, luminol‐enhanced chemiluminescence was used to study the ability of Mobiluncus spp. from the vaginas of women with bacterial vaginosis to induce, in the presence of normal adult serum, oxidative metabolism of polymorphonuclear leukocytes, which is an indirect measure of phagocytic activity. M. curtisii induced a significantly (p<0.05) lower response than M. mulieris, which indicates that M. curtisii escapes phagocytosis more easily. Indirect immunofluorescence assays showed IgG antibodies to M. curtisii at significantly (p<0.01) higher titres than to M. mulieris in women with bacterial vaginosis. The titres were higher in patients with bacterial vaginosis than in women without vaginosis and healthy men. No antibodies to Mobiluncus spp. of secretory IgA type were found in vaginal washings. These results indicate that M. curtisii is a more virulent species than M. mulieris, and agree with reports of M. curtisii found in postoperative and extragenital infections.
Evaluation of monoclonal antibodies in serovar classification of group B streptococci (GBS)
Authors: Naess AUGUSTA IRENE , Bevanger LARS , Iversen OLE‐JAN , Maeland JOHAN A.
Published: August 2009

We have produced murine MAbs against the c protein from GBS and selected one anti‐cα and one anti‐cβ MAb for serovar classification of c‐protein‐producing strains. A total of 61 GBS isolates, classified by serotype‐specific rabbit antisera, were tested in an immunofluorescent assay and whole‐cell ELISA. The MAbs permitted classification of the isolates into 13 serovars. A total of 34 strains contained the cα antigen, seven strains the cβ antigen, and 20 strains both the cα and the cβ antigen. The distribution of GBS with regard to c‐protein serovars was identical to that recorded when rabbit anti‐cα and ‐cβ sera were used. The results show that the MAbs are directed against common epitopes on cα and β, respectively. The MAbs will be useful in the serovar determination of clinical GBS isolates and in the study of the structure and immunobiology of c proteins.
Fixation of the macula densa with fixatives of different osmolalities in normal and diabetic rats
Authors: Rasch RUTH , Holck PALLE
Published: August 2009

The influence of different fixative osmolarities on the ultrastructure of the macula densa region has been studied in normal and in streptozotocin diabetic rats after 50 days' duration of diabetes. In vivo perfusion fixation of the kidneys was performed retrogradely through the aorta in five groups of controls and diabetic animals with a 1% glutaraldehyde fixative in a Tyrode solution. Between groups, the osmolarity of the fixative solution varied from 216 to 476 mosm/1. This was accomplished by variation of the NaCl concentration of the fixative vehicle. The tissue was embedded in Epon and midcortical tissue was prepared for electron microscopy. The volume density of the lateral intercellular spaces between the macula densa cells was measured applying a morphometric technique. The results confirmed that the lateral intercellular spaces are narrowed in diabetes and also showed that for all fixative osmolarities the difference is persistent between diabetic and non‐diabetic animals, except at very low osmolarities. The abnormal macula densa ultrastructure has been suggested to be connected with the functional abnormalities in diabetes, i.e. the resetting of the tubuloglomerular feedback and subsequent increases in GFR. It is therefore of interest to further understand the mechanisms underlying the narrowing of the lateral intercellular spaces in diabetes. The present study has shown that the size difference in lateral intercellular spaces between diabetic and normal animals is reproducible over a wide range of fixative osmolarities, further indicating that it is an in vivo phenomenon. The diminution of the LIS in diabetes could perhaps indicate a decrease in signal function, previously reported at the MD level in diabetic animals, contributing to the increased GFR in diabetes.
Should aerobic blood cultures be shaken intermittently or continuously?
Authors: Prag J. , Nir M. , Jensen J. , Arpi M.
Published: August 2009

Stationary incubation of aerobic blood cultures was compared with intermittent shaking in aerobic VacutainerR 2630 bottles with agar slants during the first 24 h, and was simultaneously compared with the continuously shaken aerobic BactecR 6A bottles as a reference system. Intermittent shaking did not significantly increase or decrease the seven days yield of the Vacutainer bottles as compared with the continuously agitated BactecR 6A bottles. When one of 604 paired Vacutainer bottles was agitated for eight h and the other incubated stationary, the speed of growth detection was significantly greater in the agitated bottle (p< 0.001), but significantly less than with continuously agitated Bactec 6A bottles (p< 0.001). Agitation for 14 h showed the same pattern of detection speed. These results suggest that it is desirable initially to agitate aerobic blood cultures either intermittently or continuously.
Darkening of haemoglobin in simulated, continuously agitated aerobic blood cultures: an early indicator of bacterial growth
Authors: Prag J. , Jensen J. , Lebech K.
Published: August 2009

The change of purple oxyhaemoglobin to the darker reduced haemoglobin and methaemoglobin was used as an initial visual growth indicator in continuously agitated, aerobic Colorbact® bottles after inoculation with a broad assortment of aerobic and facultatively anaerobic bacteria previously isolated from blood cultures. Growth of all the faster growing strains could be detected by darkening of the blood cultures within a 24 h period of agitation, after they had stood unshaken for eight h. The darkening was accompanied by consumption of O2 and acidification of the fluid media. The slower growing bacteria were detected by turbidity. This growth detection method is easy, quick, inexpensive and reliable, and is especially promising for application in clinical microbiological departments which daily receive blood cultures from peripheral hospitals.
Colorbact, a visually read blood culture system using darkening of haemoglobin in aerobic blood cultures as an early growth indicator, compared with Bactec® 6A and 7A
Authors: Prag J. , Jensen J. , Lebech K.
Published: August 2009

Colorbact‐A (aerobic), a blood culture system using darkening due to oxygen reduction and acidification of haemoglobin as an initial growth indicator during the first day of incubation of continuously agitated, aerobic blood cultures, was compared with the 24 h agitated aerobic Bactec® 6A in 1767 consecutive paired cultures. Both systems were examined simultaneously twice daily during the first two days and once daily the next five days of incubation. In addition, during the agitation period Colorbact‐A was observed for darkening four to five times during day duty between 8 a.m. and 4 p.m. The final seven days detection rate found by Colorbact‐A using observation for darkening during initial agitation was similar to the rate found by Bactec® 6A for both clinically significant strains and “contaminants”, but Colorbact‐A was significantly faster (p< 0.001) in finding clinically significant strains. Colorbact‐AN (anaerobic) was more rapid (p<0.01) and yielded more positive cultures than the anaerobic Bactec 7A. The Colorbact system was flexible, inexpensive, reliable and especially promising for laboratories which receive blood cultures from other hospitals once daily, as many positive cultures can be found immediately on arrival undisturbed by agitation during transport.
Prevalence of antibiotic‐resistant Escherichia coli in Danish pigs and cattle
Authors: AalbæK BENT , Rasmussen JAN , Nielsen BENT , Olsen JOHN ELMERDAHL
Published: August 2009

The present paper reports on the antibiotic resistance of E. coli isolated from Danish piglets and calves in 1987–1988, and compares the results with similar investigations performed during the periods 1971–1972 and 1977–1978. Rectal swabs from 52 piglets and from 78 calves were examined. All the animals studied haboured resistant E. coli. This is a significant increase compared to the previously conducted investigations. The number of strains having three or more resistance markers did not differ significantly from the previous findings. The spectrum of resistance markers among Danish piglets and calves had increased through all three investigations and resistance to chloramphenicol was still found to be considerable 10 years after the withdrawal of chloramphenicol as a therapeutic drug for farm animals in Denmark in 1978. Certain resistance patterns (sulfonamide + streptomycin, sulfonamide + streptomycin + tetracycline, sulfonamide + streptomycin + tetracycline + ampi‐cillin) were found to be shared by numerous strains, suggesting a genetic linkage of the resistance markers.
Tumors developing in nude mice express unusually large amounts of MHC class I antigens
Authors: Petersen BODIL LAUB , Engel ANNE MARIE , Juul‐Madsen HELLE , Mouritsen SØREN , Svane INGE , Werdelin OLE
Published: August 2009

Tumors were induced in athymic, T‐cell‐deficient nude mice and in syngeneic normal haired mice by treatment with low doses of 3‐methylcholantrene (MCA). The tumors were studied for tumor cell expression of MHC class I molecules and for immunogenicity by transplantation to syngeneic haired recipients. Ten tumors were obtained by the MCA treatment, six from nude and four from haired mice. They were all fibrosarcomas as judged from their microscopic appearance. Five of the “nude” tumors expressed measurable amounts of MHC class I molecules and two of them expressed high amounts. Both were immunogenic in the sense that they evoked a cytotoxic T‐cell response in transplanted haired recipients. Only one of the four “haired” tumors expressed measurable amounts of MHC class I., and none of them were immunogenic. These findings support the concept that some tumors are immunoselected at an early point of time in their existence in a host with a normal immune system and that this results in an elimination of tumor cell variants which are highly immunogenic for the T‐cell system, leaving the low or non‐immunogenic variants. These take over and grow and kill their host. The results suggest that tumor cell variants expressing high amounts of MHC class I are important targets in the immunoselection in hosts with a normal immune system.
Normal human serum depleted of Clq, factor D and properdin: its use in studies of complement activation
Authors: SjÖHolm ANDERS G. , Selander BARBRO , ÖStenson STEN , HolmstrÖM EVA , SÖDerstrÖM CLAES
Published: August 2009

Normal human sera were depleted of Clq, factor D (D) and properdin (P) by a simple and reproducible procedure providing reagents for analysis of complement‐dependent functions. Classical pathway activity was restored with purified Clq, and alternative pathway activity with purified D and P. Since both activation pathways were abolished, antibodies and other components could be removed without loss of complement activity during immunoabsorption procedures. Synergism between the two pathways during haemolysis of rabbit erythrocytes was clearly demonstrated, and was also found on analysis of C3 cleavage in serum incubated with other alternative pathway activators such as zymosan and inulin. Experiments with a Neisseria meningitidis serogroup W‐135 strain isolated from a patient with inherited P deficiency showed that both pathways were capable of supporting antibody‐dependent killing of the bacteria in serum. The alternative pathway was possibly more efficient than the classical pathway in the assay system. In Clq,D,P‐depleted serum with high concentrations of anticapsular IgG antibodies, the addition of D alone resulted in efficient alternative pathway‐mediated killing. The alternative pathway was equally efficient in a Clq,D,P‐depleted serum with low concentrations of anticapsular antibody, but in this case the reaction required both D and P.
Three‐dimensional reconstruction of juxtaglomerular apparatus (JGA) in five‐sixth nephrectomized rats
Authors: Faraj ABBOUD HASSAN , Morley ADRIAN ROBERTS , Coleman SHIRLEY
Published: August 2009

In Wistar male rats, hypertension was induced by five‐sixth nephrectomy (5/6N). Body weight, systolic blood pressure (SBP) and plasma renin concentration (PRC) were followed for 12 weeks after 5/6N. Three‐dimensional reconstruction and morphometry of the JGA were carried out using a computer program “GLOM”. Immunohistochemistry and electron microscopy of the JGA were also investigated. A statistically significant increase in SBP was shown after 5/6N. However, PRC showed no increase and was not correlated with SBP. Renin‐containing cells were demonstrated in the afferent and efferent arterioles and the interlobular arteries. Electron microscopy revealed granules of various shapes, sizes and electron densities within the JG cell. The frequency of granulated cells in the efferent arteriole was less than that in the afferent arteriole. The afferent arteriole wall volume of 5/6N rats was significantly increased and positively correlated with SBP. The lack of relationship between PRC and SBP in this model suggests that mechanisms other than the renin‐angiotensin system may be involved in the pathogenesis of hypertension.
Specific binding of lactoferrin to Escherichia coli isolated from human intestinal infections
Authors: Naidu S. S. , Erdei J. , CzirÓK É. , Kalfas S. , GadÓ I. , ThorÉN A. , Forsgren A. , Naidu A. S.
Published: August 2009

The degrees of human lactoferrin (HLf) and bovine lactoferrin (BLf) binding in 169 Escherichia coli strains isolated from human intestinal infections, and in an additional 68 strains isolated from healthy individuals, were examined in a 125I‐labelled protein binding assay. The binding was expressed as a percentage calculated from the total labelled ligand added to bacteria. The HLf and BLf binding to E. coli was in the range 3.7 to 73.4% and 4.8 to 61.6%, respectively. Enterotoxigenic strains demonstrated a significantly higher HLf binding (median = 19%) than enteropathogenic, enteroinvasive, enterohaemorrhagic strains or normal intestinal E. coli isolates (medians 6 to 9). Enteropathogenic strains belonging to serotypes 044 and 0127 demonstrated significantly higher HLf binding compared to O26, O55, O111, O119 and O126. No significant differences in the degree of HLf or BLf binding were found between aerobactin‐producing and non‐producing strains. The interaction was further characterized in a high Lf‐binding EPEC strain, E34663 (serotype O127). The binding was stable in the pH range 4.0 to 7.5, did not dissociate in the presence of 2M NaCl or 2M urea, and reached saturation within two h. Unlabelled HLf and BLf displaced the 125I‐HLf binding to E34663 in a dose‐dependent manner. Apo‐ and iron‐saturated forms of Lf demonstrated similar binding to E34663. Among various unlabelled subepithelial matrix proteins and carbohydrates tested (in 104‐fold excess) only fibronectin and fibrinogen caused a moderate inhibition of 125I‐HLf binding. According to Scatchard plot analysis, 5,400 HLf‐binding sites/cell, with an affinity constant (Ka) of 1.4 × 10−7 M., were estimated in strain E34663. These data establish the presence of a specific Lf‐binding mechanism in E. coli.
Cationic antigens as mediators of inflammation
Authors: BATSFORD STEPHEN R.
Published: August 2009

Electrical charge is an important determinant of antigen deposition in tissue. Cationic antigens can bind to anionic sites found in many organs. The major focus of interest has been the renal glomerulus and the articular joint. Experimental models of immune complex glomerulonephritis and allergic arthritis were established with chemically cationized proteins. More recently the concept has been extended to natural cationic proteins and human disease. The histones were shown to be potent initiators of experimental immune complex nephritis and convincing evidence for their participation in both murine and human lupus nephritis was obtained. Evidence is also presented that cationic proteins from Borrelia burgdorferi and Yersinia enterocolitica may participate in the reactive arthritis associated with these bacteria. Eucaryotic and prokaryotic nucleic acid binding proteins were identified as prime candidates for causing both immune complex glomerulonephritis and antigen‐induced allergic arthritis.
Oxidative metabolic response of peripheral blood monocytes of monkeys during primary and chronic Plasmodium knowlesi infection
Authors: JAYSHREE R.S. , GANGULY N.K. , ANJU KALRA , SETHI A. , MAHAJAN R.C.
Published: August 2009

The oxygen free radical generation (as determined by cytochrome c reduction) and respiratory burst enzyme activities were measured in the peripheral blood monocytes before infecting normal animals, during primary Plasmodium knowlesi infection, after treatment of primary infection with chloroquine, after administration of various subcurative doses following reinfection and after establishment of chronicity. For all the parameters of the oxidative response, no significant difference was observed during primary infection and after curing of primary infection. However, the response was significantly increased in the reinfected monkeys given subcurative therapy; this was followed by a sharp decline after the 4th subcurative dose, after which the response continued to be low until the attainment of chronicity. The results of the present study exclude the possibility of the increase in oxidative metabolism being the effect of the drug (i.e. chloroquine), since no significant difference was observed during primary infection and after its cure. The sustained low grade parasitaemia in the chronic stage, in spite of the sharp decrease in the oxidative response, suggests that some nonoxidant parasitic killing mechanism might be playing a role in the regulation of parasitaemia.
Expression of p21RAS in odontogenic tumors
Authors: SANDROS JENS , HEIKINHEIMO KRISTIINA , HAPPONEN RISTO‐PEKKA , STENMAN GÖRAN
Published: August 2009

Using an immunohistochemical assay 10 benign odontogenic tumors were evaluated for expression of the HRAS‐ and KRAS‐encoded gene products p21RAS. Overexpression of p21RAS was found in ameloblastomas, ameloblastic fibromas and odontogenic myxomas compared with normal human developing teeth. The highest expression was noted in a recurrent plexiform ameloblastoma in which almost 100% of the tumor cells were brightly reactive. In general, p21RAS was preferentially expressed in ectodermal cells of odontogenic tumors, consistent with the findings in the tooth germs. The significance of p21RAS expression is considered in relation to the biological behavior of ameloblastomas.
Isolation and characterization of a soluble antigen complex of Plasmodium falciparum with pyrogenic properties
Authors: JAKOBSEN P. H. , HVIID L. , THEANDER T. G. , RILEY E. M. , GRELLIER P. , BRUUN L. S. , DALSGAARD K. , SCHREVEL J. , JEPSEN S.
Published: August 2009

A soluble antigen complex, previously designated antigen no. 7 (Ag7) on the basis of the pattern obtained by crossed immunoelectrophoresis of culture supernatants of P. falciparum, was isolated by affinity chromatography. It was shown to be synthesized at the schizont stage of the parasite growth cycle and to be located on the surface of the schizonts. Antibodies to Ag7 did not inhibit the growth of the parasite in vitro. Ag7 is recognized by immune human sera from many parts of the world and it stimulated the production of specific antibody in mice when incorporated into immune‐stimulating complex (ISCOM) structures. It also specifically stimulated in vitro proliferation of lymphocytes from clinically immune adults. That it induced the secretion of interleukin 1 by human monocytes and was pyrogenic in rabbits was of particular interest. Thus Ag7 has endotoxin‐like properties which make it a possible candidate for an antitoxic malaria vaccine.
Viral RNA species in cell lines persistently and lytically infected with measles virus
Authors: KALLAND KARL‐H. , KALVENES MAY BRITT , HAUKENES GUNNAR
Published: August 2009

Identical measles viral mRNA species were present in similar amounts in the persistently infected cell lines LU106, HEpPi and MaSSPE, and in lytically infected cells as determined from Northern blots. The attenuation of transcription with the gene order did not vary significantly between different infected systems. A previously described selective restriction of F protein production in Lu 106 cells could not be explained by defective transcription of F mRNA. RNA synthesis also continued unimpeded at restrictive temperatures for the temperature‐sensitive viruses in Lu106 and HEpPi cells. Northern blotting revealed a prominent band in HEpPi RNA and a weak band in Lu106 RNA with the characteristics of incomplete genomes. In all infected cells, previously unrecognized small RNA species, hybridizing with the F‐ and H‐specific probes, were discovered.
A conserved domain on enterobacterial porin protein analysed by monoclonal antibody
Authors: HENRIKSEN ARNE Z. , MÆLAND JOHAN A.
Published: August 2009

Broadly cross‐reactive monoclonal antibodies (MAbs) against enterobacterial outer membrane (OM) porin (Po) protein were isolated after immunization of BALB/c mice with whole cells of E. coli 055:B5. MAbs (n=6) of the IgG class but of four different isotypes were studied. Based on a competition ELISA, all of the MAbs were directed against one and the same Po protein domain (PoI). The MAbs cross‐reacted with 72 of 74 strains from 10 different genera of the Enterobacteriaceae. One Morganella and one Salmonella strain showed no cross‐reactivity. Also, nine strains of various Neisseria spp. cross‐reacted while 21 strains of various other nonenteric Gram‐negative bacteria showed no cross‐reactivity. The Po I sites were inaccessible in intact homologous bacteria but partially accessible in the OM. Digestion of OM with lysozyme or lysostaphin affected the accessibility of the Po I sites in OMs of various enterobacteria. Lysostaphin strongly enhancefd the immunoaccessibility, whereas lysozyme had lesser effects. The enzymes also affected the binding by Neisseria OMs of the anti‐Po I MAb. The Po I site was immunogenic both in humans and rabbits. The data indicate that Po I is an important Po protein domain, and that the effects of peptidoglycan‐degrading enzymes must be considered in studies of Po protein domains.
Interleukin‐6 and tumour necrosis factor alpha are expressed by keratinocytes but not by Langerhans cells
Authors: OXHOLM ANNEMETTE , DIAMANT MARCUS , OXHOLM PETER , BENDTZEN KLAUS
Published: August 2009

The presence of human cytokines was examined in parallel skin biopsies and epidermal single cell preparations obtained from normal individuals. Using biotin‐avidin‐peroxidase and immunofluorescence techniques and antibodies against recombinant cytokines, a granular intercellular/membrane‐associated staining for interleukin‐6 (IL‐6) and tumour necrosis factor alpha (TNF alpha), but not IL‐1 alpha or beta, was observed. An epidermal cytoplasmic staining pattern was also detected, which was most pronounced using the anti‐rIL‐6 antiserum. In the epidermal single cell preprations, membrane‐associated staining was detected for both IL‐6 and TNF alpha. Double staining revealed that CD1‐positive Langerhans cells (LC) failed to express any of the examined cytokines. In vitro binding of rIL‐6 or rTNF alpha to skin sections and epidermal single cell preparations indicated that the cell surface‐associated IL‐6 and TNF alpha originally demonstrated on keratinocytes were truly membrane‐bound. Finally, co‐cultivation of epidermal cells with an IL‐6 responsive cell line, B9, and testing of epidermal cell supernatants in this assay, indicated that the in vivo membrane‐bound IL‐6 had biological activity.