Search Results - (Author, Cooperation:L. Christensen)

2018-03-16

The American Association for Cancer Research (AACR)

1078-0432

1557-3265

Medicine

2018-07-03

The American Association for Cancer Research (AACR)

0008-5472

1538-7445

Medicine

2016-03-26

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

Allosteric Regulation ; Arabidopsis Proteins/antagonists & inhibitors/chemistry/*metabolism ; Hydrogen-Ion Concentration ; Ion Transport ; Membrane Potentials/drug effects/physiology ; Molecular Imaging ; Protein Structure, Tertiary ; Proton-Translocating ATPases/antagonists & inhibitors/chemistry/*metabolism ; *Protons ; Valinomycin/pharmacology

2015-03-04

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

2018-06-08

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Geosciences

Computer Science

Medicine

Natural Sciences in General

Physics

Geochemistry, Geophysics, Planetary Science

1089-7623

AIP Digital Archive

Physics

Electrical Engineering, Measurement and Control Technology

An improved and reliable method for making sharp scanning tunneling microscopy (STM) tips is described. It is based on the widely used drop-off electrochemical etching procedure, here modified to improve the control of the tip shape. A second etching is applied not only to remove the oxide layer from the tip surface, but also to sharpen the STM tips further. A tip radius less than 20 nm can be obtained reproducibly. The quality of the produced tips was inspected with transmission electron microscopy, and micrographs of tips produced with different times of second etching are shown. To produce tips which are all without an oxide layer an electronic phase control unit is necessary. Even without this etch controller more than half the tips are oxide free, and then only standard laboratory equipment is used for the tip production.

Electronic Resource

1600-0528

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Abstract The present study was conducted to compare level of dental caries, treatment pattern and contact patterns with the Child Oral Health Care System of children of immigrants. The study comprised 239 Turkish, 117 Pakistani and 91 other immigrants and a control group of 359 Danish children. Data were extracted from the dental records in the clinic where they were treated. All groups of immigrants showed more caries in the primary dentition and less caries in the permanent dentition than Danish children of comparable age. For preschoolchildren a higher number of broken appointments were found for the immigrants as well as a higher number of appointments which were interrupted due to management problems. The consequences for planning preventive and restorative programs for children of immigrants are discussed.

Electronic Resource

1750-3841

Blackwell Publishing Journal Backfiles 1879-2005

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Process Engineering, Biotechnology, Nutrition Technology

: The effects of genotype, root size, storage, and processing on the content of bioactive compounds in carrots were determined to investigate the possibilities for optimizing the health-promoting properties of this vegetable. The content of polyacetylenes (falcarinol, falcarindiol, falcarindiol-3-acetate), carotenoids (α-and β-carotene), and isocoumarin 6-methoxymellein (6-MM) varied significantly between 6 genotypes of the Nantes type. The content of falcarindiol, falcarindiol-3-acetate, and 6-MM was significantly higher in small (50- to 100-g root size) than in extra large root sizes (〉250-g root size). Refrigerated storage of the roots for 4 mo at 1 °C before processing resulted in a significantly higher content of polyacetylenes and no differences in the content of carotenoids and 6-MM compared with frozen storage of processed carrots. The content of falcarinol increased and that of falcarindiol and falcarindiol-3-acetate decreased during steam blanching of the carrots before freezing. No changes were observed in the content of carotenoids and 6-MM.

Electronic Resource

1439-0523

Blackwell Publishing Journal Backfiles 1879-2005

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

The tepals of 28 Chilean species of Alstroemeria and 183 interspecific hybrids were analysed for anthocyanin content by high-performance liquid chromatography (HPLC). The anthocyanins were identified as 3-rutinosides of 6-hydroxydelphinidin, 6-hydroxyeyanidin, cyanidin, and delphinidin and 3-glyeosides of cyanidin and delphinidin, some of which were acylated with malonic acid. Comparisons of the anthocyanin contents in parents and offspring showed that no anthocyanidin or acylation pattern was dominant, and that offspring values were close to mid-parent values for the percentage of malonated anthocyanins, whereas the inheritance of cyanidin, 6-hydroxycyanidin, and delphinidin seems more complicated. Flower colour, hue, and intensity were measured by CIELab in fresh tepals and compared with their anthocyanin content and the estimated flavonoid concentrations. Colour intensity was positively correlated with anthocyanin concentration. Compared with flowers containing exclusively cyanidin 3-glycosides, the hues of flowers with delphinidin 3-glycosides were bluer and with 6-hydroxycyanidin 3-glycosides redder, respectively. Both malonation of anthocyanin and co-pigmentation with flavonoids caused a shift to bluish hues, irrespective of the anthocyanidins. By quantifying both chemical and colorimetric characteristics a model for the effect of anthocyanin on Alstroemeria flower colour was established. Breeding of new cultivars of Alstroemeria is discussed.

Electronic Resource

1365-3083

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

CD73 is a bifunctional glycosyl phosphatidylinositol anchored leucocyte differentiation antigen which has specific ecto-5′-nucleotidase (ecto-5′-NT) activity and is an accessory T-lymphocyte activation molecule. The aim of the present study was to investigate the CD73 expression on blood mononuclear cells (BMC) from a group of patients with primary immunoglobulin deficiency (IGD). This group of patients had both significantly decreased levels of ecto-5′-NT on BMC (P = 0.002) and decreased numbers of CD73 molecules per CD73+ lymphocyte (P = 0.01). Five of the 10 patients had a decreased percentage of CD73+ lymphocytes. Among B-lymphocytes the patients had normal percentages of CD73+ cells but four of the 10 patients had numbers of CD73 molecules per CD73+ B-lymphocyte below the normal range. Among CD4-lymphocytes three out of 10 patients had percentages of CD73+ below the normal range and four out of 10 patients had decreased percentages of CD73+ CD8-lymphocytes. Significant correlations were found between in vitro proliferative responses to mitogens and the number of CD73 molecules per CD73+ lymphocyte (rs = 0.60, P 〈 0.01) and per CD73+ CD8-lymphocyte (rs = 0.64, P 〈 0.02). In addition, a positive correlation was found between ability to proliferate and level of ecto-5′-NT on BMC (rs = 0.53, P 〈 0.05). Furthermore the ability of BMC to synthesize ecto-5′-NT was studied. During 2 days' culture ecto-5′-NT activity increased markedly on BMC from both patients and healthy donors. The level of activity on BMC from all patients attained levels higher than on freshly isolated BMC from healthy donors. This shows that the decreased levels of ecto-5′-NT found on freshly isolated BMC from patients with IGD is due to defective regulation of the enzyme activity in vivo

Electronic Resource

1365-3083

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

The present study was designed to examine the effect of physical exercise on subsets and proliferative responses of blood mononuclear cells. Sixteen young, healthy volunteers underwent 60min of bicycle exercise at 75% of maximal oxygen uptake (VO2max). After an interval of at least 1 week, six of the subjects underwent a 60-min back muscle training period at up to 30% of VO2max. Blood samples were collected before and during the last minutes of exercise, as well as 2 and 24 h later. Blood mononuclear cell (BMNC) subpopulations were determined and the proliferate responses after incubation with phytohaemagglutinin (PHA) or purified derivative of tuberculin (PPD), were quantified by [3H]thymidine incorporation. During bicycle exercise the relative blood concentration of T cells (CD3+ cells) declined, mainly due to a fall in T helper cells (CD4+ cells). The natural killer (NK) cell subset (CD16+ cells) increased during work, but reverted after; the monocytes (CD14+ cells) increased 2 h after work, whereas the B-cell subset (CD20+ cells) did not change. BMNC subsets were not significantly changed by back muscle exercise. The PHA-induced proliferative response decreased during bicycle exercise, whereas the PPD-induced response did not change. No significant changes occurred during back muscle exercise. Investigation of subgroups after incubation with [3H]thymidine showed that the proliferative response per CD4+ cell did not change in relation to exercise, but the contribution of the CD4+ subgroup to proliferation declined during bicycle exercise due to the decreased proportion of CD4+ cells. The suppression of the PHA response during bicycle exercise can be explained in part by a relative fall in CD4+ cells. The pool sizes of BMNC subfraction may be elicited by increased catecholamine and cortisol levels.

Electronic Resource

1365-3083

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

The authors tested an alternative method for CD4 and CD8 T lymphocytes enumeration, the immunoalkaline phosphatase method (IA), in three African countries and in Denmark. The IA determinations from 136 HIV antibody positive and 105 HIV antibody negative individuals were compared to the corresponding results obtained by flow cytometry (FC) performed in the respective countries. The authors found good correspondence between the two methods for measurements of CD4 and CD8 T lymphocytes independent of serological status and geographical site. However, the CD4 and CD8 T lymphocyte values obtained by the two methods are not interchangeable as IA compared to FC consistently gives higher percentage of CD4 T lymphocytes, and lower percentages of CD8 T lymphocytes. Mean differences between the two methods did not differ between the three African countries indicating that the IA method provides systematic results. Replicate measurements suggested good correspondence between results obtained by IA. By using an IA level of 〈 300 CD4 T lymphocytes/μl, the sensitivity was 81% and specificity 96% for detecting an FC level of 〈 200 CD4 T lymphocytes/μl. Using an IA level of 〈 20% CD4 T lymphocytes, the sensitivity was 89% and specificity 95% for detecting an FC level of 〈14% CD4 T lymphocytes, The FC and IA methods had the same internal correspondence between low absolute CD4 T cell counts and low CD4 percentages; the sensitivity and specificity for detecting a low absolute CD4 T cell count with a low CD4 percentage was 92% and 68% for FC and 91% and 73% for IA, respectively. The IA method is 10-fold cheaper than FC, is independent of advanced laboratory facilities, and does not need immediate processing of samples as blood smears can be stored for long periods. The IA method is therefore suitable for use in areas with limited resources and laboratory facilities where there is a need for immunological surveillance in hospital or community studies.

Electronic Resource

1365-3083

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

The cysteine protease Der p1 from dust mite of the genus Dermatophagoides pteronyssinus is a major type I allergen. About 80% of house dust mite (HDM) allergic individuals are reactive to this protease in standard assays for detection of IgE. A curative treatment for atopic allergy is immunotherapy (IT) with HDM extracts which are complex mixtures occasionally resulting in anaphylactic reactions. Novozymes focuses on developing a recombinant variant of Der p1 which exhibit lowered risk of IgE-mediated allergic reactions, while maintaining its ability to trigger proper Th-cell responses. This may provide a safer alternative for specific IT of HDM allergy. A secreted recombinant form of pro-Der p 1 expressed by Saccharamyces cerevisiae was obtained by fusion of the pro-enzyme to a fungal signal peptide. The N-glycosylation site of Der p1 was mutated resulting in a deglycosylated pro-enzyme with a molecular mass of 35 kDa. Protein purification procedure was developed to obtain nearly pure Der p1 protein followed by determination of concentration by active-site-titration with the cysteine protease inhibitor E64. The deglycosylated recombinant pro-Der p 1 revealed immunologic similarity to the native Der p 1 molecule when compared in basophile histamine release, IgE-binding assays and T-cell proliferation assays. By in silico epitope mapping of a modelled 3-dimensional structure of Der p1, five putative IgG and IgE epitopes were predicted. By protein engineering, the predicted epitopes were removed one by one in Der p1 and screening for hypoallergenic variants was performed.

Electronic Resource

1365-3040

Blackwell Publishing Journal Backfiles 1879-2005

Biology

Distinct synchronous diurnal rhythms were detected in the concentrations of phenethyl alcohol and phenethyl acetate in the tissue of blooming Trifolium repens florets. Corresponding rhythmic oscillations were observed for the same two compounds in the floral headspace. Maximum content of the volatiles in the tissue and headspace was observed 3–9 h after initiation of the photophase. The concentrations of phenethyl alcohol and phenethyl acetate in the tissue increased significantly during floral development. At full bloom the tissue contained amounts sufficient to support 2–3 h of emission. Several observations suggested that esterification of phenethyl alcohol was the source for phenethyl acetate. Trimethylsilyl derivatization and enzymatic hydrolysis of fractionated flower extracts identified 2-phenylethyl β-d-glucopyranoside as the major glucoside in the florets. The pool of glucosides increased significantly during floral development and at full bloom 97% of the phenethyl alcohol was bound as glucoside. The concentration of 2-phenylethyl β-d-glucopyranoside did not vary in a rhythmic diurnal manner. The dynamics among the diurnal rhythmic phenomena in the tissue and headspace and the fraction of volatiles bound as glucosides is discussed.

Electronic Resource

1365-2559

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

The expression of tetranectin in colonic neoplasia was evaluated by determining the tissue distribution by immunohistological analysis of tissue sections and the antigen levels in tissue homogenates and plasma. In normal colonic mucosa tetranectin staining was predominantly found in the goblet cells whereas in adenocarcinomas this staining was confined to the tumour stroma. Colonic adenomas, benign precursors of adenocarcinomas, showed fewer tetranectin positive goblet cells and in some cases showed tetranectin expression in the stroma. Within the tissue homogenates no differences were found in the tetranectin levels between normal mucosa, adenomas and carcinomas. Patients with colonic cancer were found to have significantly decreased plasma tetranectin levels compared to healthy controls. Thus, colonic neoplasia is associated with a change in the tissue distribution of tetranectin, without an obvious change in the tissue level, and a low plasma tetranectin level.

Electronic Resource

1600-0560

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Angiogenesis and the extracellular matrix are fundamental to tumor progression from in situ to invasive and metastatic disease. Laminin, a major glycoprotein integrated into basement membranes, is observed in angiogenesis and tumorigenesis. A recent study described an association between melanoma cells and endothelial cells via an amorphous matrix containing laminin. In the current study, we have examined 45 cases of human primary and metastatic melanomas by electron microscopy for the presence of an amorphous matrix. We observed an amorphous matrix without a clearly delineated lamina or basement membrane in 41 of the 45 melanomas studied. 28 cases with tissue blocks available for study were examinated by immunohistochemistry for the expression of laminin and type IV collagen. We observed die presence of an angiocentric matrix containing laminin in 24 of the 28 melanomas studied. Since laminin is involved in tumor migration, the presence of laminin between melanoma cells and small vessels suggests a role for this material in periendothelial tumor migration. However, further study is required to characterize the nature of this material and the mechanisms involved.

Electronic Resource

1600-0536

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

The Compositae plant feverfew (Tanacetum parthenium) is an important sensitizer in Europe and has been suspected of causing airborne Compositae dermatitis. A previous investigation of substances emitted from feverfew plants detected no sesquiterpene lactones, however, but mainly monoterpenes. The aims of this study were to test whether feverfew-allergic patients were also sensitive to some of the above-mentioned monoterpenes and, if so, to study associations between sensitization patterns, relevance of feverfew allergy and clinical features. 17 patients with + +/+ + + reactions to feverfew and parthenolide were tested with 15 selected monoterpenes and 2 sesquiterpenes. Of the 17 persons, 13 had positive and/or doubtful positive reactions to 1 or more monoterpenes. Only 1 person was allergic to several monoterpenes. Her history of gradually worsening Compositae dermatitis culminating in a probable airborne dermatitis, mimicking photosensitivity, and the disappearance of symptoms upon removal of feverfew plants suggest monoterpenes as a possible contributing factor. Similar associations between doubtful positive monoterpene reactions and clinical patterns, fragrance/colophonium allergy and relevance of feverfew allergy were not established with certainty. In conclusion, sensitization to the sesquiterpene lactones of feverfew is not invariably accompanied by sensitization to its volatile monoterpenes. The presence of monoterpene allergy, however, may contribute to airborne Compositae dermatitis.

Electronic Resource

0165-0327

Cyclic antidepressants ; Endogenous depression ; Plasma cortisol levels

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Medicine

Psychology

Electronic Resource

0005-7894

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Psychology

Electronic Resource

0005-7894

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Psychology

Electronic Resource