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Christensen J, Povlsen VT, Sørensen J. Application of fluorescence spectroscopy and chemometrics in the evaluation of processed cheese during storage. J Dairy Sci 2003; 86:1101-7. [PMID: 12741533 DOI: 10.3168/jds.s0022-0302(03)73692-3] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Front face fluorescence spectroscopy is applied for an evaluation of the stability of processed cheese during storage. Fluorescence landscapes with excitation from 240 to 360 nm and emission in the range of 275 to 475 nm were obtained from cheese samples stored in darkness and light in up to 259 d, at 5, 20 and 37 degrees C, respectively. Parallel factor (PARAFAC) analysis of the fluorescence landscapes exhibits four fluorophores present in the cheese, all related to the storage conditions. The chemometric analysis resolves the fluorescence signal into excitation and emission profiles of the pure fluorescent compounds, which are suggested to be tryptophan, vitamin A and a compound derived from oxidation. Thus, it is concluded that fluorescence spectroscopy in combination with chemometrics has a potential as a fast method for monitoring the stability of processed cheese.
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Rasmussen A, Christensen J, Clemmensen PM, Dalsgaard NJ, Dam H, Hindberg I, Lunde M, Plenge P, Mellerup E. Platelet serotonin transporter in stroke patients. Acta Neurol Scand 2003; 107:150-3. [PMID: 12580867 DOI: 10.1034/j.1600-0404.2003.02053.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVES Post-stroke depression can be treated with serotonin transport inhibitors suggesting a role for the serotonin system in these patients. The number of platelet serotonin transporters in stroke patients and in control subjects have been measured in this study. MATERIAL AND METHODS Newly admitted stroke patients who did develop or who did not develop a post-stroke depression, non-acute patients who previously had had a stroke and control subjects were compared. The number of platelet serotonin transporters was analysed by ligand binding methodology. RESULTS The number of platelet serotonin transporters was low shortly after a stroke compared with normal subjects; no difference was found between the stroke patients who developed a post-stroke depression and those who did not. CONCLUSION A low number of platelet serotonin transporters may be a non-specific state marker for a condition as acute stroke.
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Baronas R, Christensen J, Ivanauskas F, Kulys J. Computer Simulation of Amperometric Biosensor Response to Mixtures of Compounds. ACTA ACUST UNITED AC 2002. [DOI: 10.15388/na.2002.7.2.15190] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A mathematical model of amperometric biosensors has been developed. The model bases on non-stationary diffusion equations containing a non-linear term related to Michaelis-Menten kinetic of the enzymatic reaction. The model describes the biosensor response to mixtures of multiple compounds in two regimes of analysis: batch and flow injection. Using computer simulation, large amount of biosensor response data were synthesised for calibration of a biosensor array to be used for characterization of wastewater. The computer simulation was carried out using the finite difference technique.
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Jolles S, Christensen J, Holman M, Klaus GB, Ager A. Systemic treatment with anti-CD40 antibody stimulates Langerhans cell migration from the skin. Clin Exp Immunol 2002; 129:519-26. [PMID: 12197894 PMCID: PMC1906468 DOI: 10.1046/j.1365-2249.2002.01909.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Epidermal Langerhans cells (LCs) play a pivotal role in the initiation of cutaneous immune responses. The maturation of LCs and their migration from the skin to the T cell areas of draining lymph nodes are essential for the delivery and presentation of antigen to naïve T cells. CD40, which acts as a costimulatory molecule, is present on LCs and the basal layer of keratinocytes in the skin. We show here that systemic treatment of mice with anti-CD40 antibody stimulates the migration of LCs out of the epidermis with a 70% reduction in LC numbers after 7 days, although changes in LC morphology are detectable as early as day 3. LC numbers in the epidermis returned to 90% of normal by day 21. As well as morphological changes, LC showed up-regulated levels of Class II and ICAM-1, with only minimal changes in CD86 expression 3 days following anti-CD40 treatment. Despite increased levels of Class II and ICAM-1, epidermal LC isolated from anti-CD40 treated mice were poor stimulators of a unidirectional allogeneic mixed leucocyte reaction (MLR), as were epidermal LC isolated from control mice. These results indicate that CD40 stimulation is an effective signal for LC migration, distinct from maturation of immunostimulatory function in the epidermis, which is not altered. These observations may have important implications for the mechanism of action of agonistic anti-CD40 antibodies, which have been used as an adjuvant in models of infection and experimental tumours and the primary immunodeficiency Hyper IgM syndrome caused by deficiency of CD40 ligand.
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Christensen J. Promoting parental use of distraction and relaxation in pediatric oncology patients during invasive procedures. J Pediatr Oncol Nurs 2002. [DOI: 10.1053/jpon.2002.126055] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Ducoux M, Urbach S, Baldacci G, Hübscher U, Koundrioukoff S, Christensen J, Hughes P. Mediation of proliferating cell nuclear antigen (PCNA)-dependent DNA replication through a conserved p21(Cip1)-like PCNA-binding motif present in the third subunit of human DNA polymerase delta. J Biol Chem 2001; 276:49258-66. [PMID: 11595739 DOI: 10.1074/jbc.m106990200] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The subunit that mediates binding of proliferating cell nuclear antigen (PCNA) to human DNA polymerase delta has not been clearly defined. We show that the third subunit of human DNA polymerase delta, p66, interacts with PCNA through a canonical PCNA-binding sequence located in its C terminus. Conversely, p66 interacts with the domain-interconnecting loop of PCNA, a region previously shown to be important for DNA polymerase delta activity and for binding of the cell cycle inhibitor p21(Cip1). In accordance with this, a peptide containing the PCNA-binding domain of p21(Cip1) inhibited p66 binding to PCNA and the activity of native three-subunit DNA polymerase delta. Furthermore, pull-down assays showed that DNA polymerase delta requires p66 for interaction with PCNA. More importantly, only reconstituted three-subunit DNA polymerase delta displayed PCNA-dependent DNA replication that could be inhibited by the PCNA-binding domain of p21(Cip1). Direct participation of p66 in PCNA-dependent DNA replication in vivo is demonstrated by co-localization of p66 with PCNA and DNA polymerase delta within DNA replication foci. Finally, in vitro phosphorylation of p66 by cyclin-dependent kinases suggests that p66 activity may be subject to cell cycle-dependent regulation. These results suggest that p66 is the chief mediator of PCNA-dependent DNA synthesis by DNA polymerase delta.
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Burnett E, Christensen J, Tattersall P. A consensus DNA recognition motif for two KDWK transcription factors identifies flexible-length, CpG-methylation sensitive cognate binding sites in the majority of human promoters. J Mol Biol 2001; 314:1029-39. [PMID: 11743720 DOI: 10.1006/jmbi.2000.5198] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Parvovirus initiation factor (PIF), identified in HeLa cells as a host factor essential for parvoviral DNA replication, is a ubiquitous heterodimeric cellular transcription factor. This protein complex was simultaneously identified as glucocorticoid modulatory element binding protein (GMEB) by its ability to bind to the glucocorticoid modulating element (GME) upstream of the tyrosine transaminase promoter. Here, we show that the two PIF/GMEB subunits form site-specific DNA-binding heterodimers when co-expressed from recombinant baculoviruses and homodimers when expressed separately. Degenerate oligonucleotide selection experiments, combined with analysis of dissociation rates, established that the three complexes bind to flexibly spaced tetranucleotide half-sites that conform to the consensus ACGPy N(1-9) PuCGPy, with an optimum of N=6. Binding of all three complexes is extremely sensitive to methylation of the cytosine residues in the invariant CpG half-site core, suggesting a means by which PIF/GMEB binding could be regulated in vivo. Because CpG dinucleotides are suppressed in eukaryotic genomes, such binding sites would be expected to be very rare. However, analysis of 100 human promoters showed that over half of them contained at least one site conforming to the consensus, a significant deviation from the expected random distribution. In many of these, the binding site is within 100 nucleotides of the transcriptional start site, indicating that PIF/GMEB may be involved in regulation of these genes. Oligonucleotides corresponding to five of these sequences, chosen to represent the range of half-site separations identified by the consensus, were tested for PIF/GMEB binding by mobility shift assay. All five probes bound the heterodimer efficiently and, in each case, binding was completely abrogated by 5-methylation of the C residues in the CpGs of the putative half-sites.
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Alban L, Stryhn H, Kjeldsen AM, Ersbøll AK, Skjøth F, Christensen J, Bitsch V, Chriél M, Strøger U. Estimating transfer of bovine virus-diarrhoea virus in Danish cattle by use of register data. Prev Vet Med 2001; 52:133-46. [PMID: 11679171 DOI: 10.1016/s0167-5877(01)00241-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
To study how routinely recorded data (also called "register data") might be used in disease monitoring on a regional or national level, a database for bovine virus-diarrhoea virus (BVDV) was made from existing databases, covering the period January 1995-November 1999. This paper includes a general description of the database, including basic statistics for selected variables. Information was largely complete for cattle herds in the milk-recording scheme (MRS), but only partly available for other herds. A methodology was developed to identify when and how a herd initially was infected. For most herds, it was possible to determine when and how BVDV first was introduced. Among the infected herds, most were already infected by the start of the study. BVDV had been present in 40% of the MRS herds and in 9% of the non-MRS herds. In the MRS herds, most new infections were associated with a dam that had been present in the same herd during gestation. Among the non-MRS herds, most new infections were associated with movement of a persistently infected animal. The monthly number of newly infected herds is presented; it is seen that the incidence declined substantially during the study period.
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Lund O, Christensen J, Holme S, Fruergaard K, Olesen A, Kassis E, Abildgaard U. On-pump versus off-pump coronary artery bypass: independent risk factors and off-pump graft patency. Eur J Cardiothorac Surg 2001; 20:901-7. [PMID: 11675172 DOI: 10.1016/s1010-7940(01)00972-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE Current knowledge on off-pump coronary artery bypass (OPCAB) generally stems from single surgeons' experience or from series where OPCABs constituted a minor fraction of coronary operations. The present center decided to venture as far into OPCAB as possible during 1999. The present series thus represents the average surgeon's experience. METHODS During 1999, 533 patients underwent coronary artery bypass grafting using cardiopulmonary bypass (CPB) in 368 and OPCAB in 165 including the circumflex artery (CX) area in 91. Coronary arteriography was performed before discharge in the first 103 OPCAB patients. RESULTS The CPB and OPCAB groups differed as regards left ventricular ejection fraction (53+/-13 versus 57+/-11, P < 0.0001) and frequency of triple-vessel or left main stem disease (84 versus 32%, P < 0.0001) but were comparable as regards diabetes (12%), prior myocardial infarct (57%), unstable angina (21%), and previous heart surgery (3%). Using multivariate analyses, 30-day mortality (1.3%), P-creatine kinase myocardial band (CKMB) > 80 microg/l (11.1%), re-sternotomy for bleeding (4.5%) or dehiscense (1.7%), transitory cerebral ischemia and stroke (1.7%), supraventricular tachycardia (27.4%), and hospital stay (mean 8 days) were unrelated to off- versus on-pump surgery as well as to OPCAB in triple-vessel disease. CX branches < or = 1mm, > or = 5 distal anastomoses, prior heart surgery, right coronary artery (RCA) branches < or = 1.5mm, 8-21 days old myocardial infarct, female gender, and preoperative acute arrhythmia (among others) were identified as independent risk factors for mortality or increased CKMB in all 533 patients. The latter five risk factors were reproduced in the OPCAB group isolated. The patency in the 103 OPCABs was 95.3, 91.8, and 85.3% in the left anterior descending artery (LAD), CX, and RCA, respectively. Patency was inversely related to diameter of the grafted vessel in the LAD and CX areas, unlike the RCA area. CONCLUSIONS The results after beating heart surgery were good also in patients with triple-vessel disease, but specific gains relative to on-pump surgery could not be shown. The independent risk factors in the OPCAB group may indicate relative contraindications for OPCAB grafting.
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Sairafianpour M, Christensen J, Staerk D, Budnik BA, Kharazmi A, Bagherzadeh K, Jaroszewski JW. Leishmanicidal, antiplasmodial, and cytotoxic activity of novel diterpenoid 1,2-quinones from Perovskia abrotanoides: new source of tanshinones. JOURNAL OF NATURAL PRODUCTS 2001; 64:1398-1403. [PMID: 11720520 DOI: 10.1021/np010032f] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Cryptotanshinone (1), a quinoid diterpene with a nor-abietane skeleton, and three new natural products, 1beta-hydroxycryptotanshinone (2), 1-oxocryptotanshinone (3), and 1-oxomiltirone (4), were isolated from roots of the Iranian medicinal plant Perovskia abrotanoides. Their structures were established using homo- and heteronuclear two-dimensional NMR experiments, supported by HRMS. The total amount of tanshinones isolated from dry roots of Perovskia abrotanoides was about 1.5%. The compounds exhibited leishmanicidal activity in vitro (IC(50) values in the range 18-47 microM). These findings provide a rationale for traditional use of the roots in Iran as a constituent of poultices for treatment of cutaneous leishmaniasis. The isolated tanshinones also inhibited growth of cultured malaria parasites (3D7 strain of Plasmodium falciparum), drug-sensitive KB-3-1 human carcinoma cell line, multidrug-resistant KB-V1 cell line, and human lymphocytes activated with phytohaemagglutinin A (IC(50) values in the range 5-45 microM). The toxicity of tanshinones toward the drug-sensitive KB-3-1 and the multidrug-resistant KB-V1 cells was the same, indicating that the compounds are not substrates for the P-glycoprotein drug efflux pump.
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Davidson B, Nielsen S, Christensen J, Asschenfeldt P, Berner A, Risberg B, Johansen P. The role of desmin and N-cadherin in effusion cytology: a comparative study using established markers of mesothelial and epithelial cells. Am J Surg Pathol 2001; 25:1405-12. [PMID: 11684957 DOI: 10.1097/00000478-200111000-00008] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The objective of the present study was to analyze the role of the mesothelial markers desmin and N-cadherin in the diagnostic panel of serous effusions. A total of 181 pleural and peritoneal effusions consisted of 101 cases cytologically diagnosed as malignant (89 carcinomas, 12 mesotheliomas), 78 benign, and 2 inconclusive specimens. All specimens were immunostained using 11 antibodies, against epithelial membrane antigen, Ber-EP4, carcinoembryonic antigen, E-cadherin, CA 125, N-cadherin, desmin, calretinin, p53, vimentin, and CD45. After evaluation of immunocytochemistry results, 110 specimens were diagnosed as malignant (98 carcinomas, 12 mesotheliomas) and 71 as benign (56 cellular, 15 paucicellular). The presence of desmin was detected in benign mesothelial cells in 47 of 56 (84%) reactive cellular specimens compared with 1 of 12 (8%) malignant mesotheliomas and 2 of 98 (2%) carcinomas. N-cadherin was expressed in 48 of 56 (86%) reactive cases, 12 of 12 (100%) mesotheliomas, and 47 of 98 (48%) carcinomas. In carcinomas, N-cadherin expression was most often seen in ovarian carcinoma but was also found in other carcinomas. Calretinin, an established marker of mesothelial cells, was detected in 52 of 56 (93%) reactive specimens, 11 of 12 (93%) mesotheliomas, and 3 of 98 (3%) carcinomas. Evaluation of staining results led to reclassification of six malignant specimens as benign, whereas 17 cases diagnosed as benign and the two diagnosed as inconclusive were classified as malignant. In conclusion, desmin appears to be a promising marker for the distinction between reactive mesothelium and malignant epithelial cells in terms of both specificity and sensitivity, and its complementary use with calretinin is recommended. Unlike calretinin, it may also prove valuable for the distinction between benign and malignant mesothelial cells. N-cadherin does not have a role in the distinction between mesothelial and epithelial cells. However, it may prove useful in the characterization of carcinomas of unknown origin. As has previously been shown, a significant number of diagnoses that are based on morphologic examination alone are modified after the use of a broad antibody panel.
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Heegaard ED, Panum Jensen I, Christensen J. Novel PCR assay for differential detection and screening of erythrovirus B19 and erythrovirus V9. J Med Virol 2001; 65:362-7. [PMID: 11536245 DOI: 10.1002/jmv.2042] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Diagnosis of erythrovirus B19 relies on serology and the detection of viral DNA. These techniques were believed to detect all field isolates because erythrovirus B19 has been known to undergo little genetic variation (1-2%). Recently, a distinct erythrovirus isolate termed V9, markedly different from erythrovirus B19 (>11% nucleotide disparity), was isolated from a child in France suffering from transient aplastic anemia. Standard PCR assays and serological tests failed to demonstrate an acute erythrovirus B19 infection. Subsequent sequencing of the erythrovirus V9 genome shows that the nucleotide discrepancies encompass the entire genome, indicating that standard erythrovirus B19 PCR assays will not reliably detect erythrovirus V9 DNA. As a tool for studying the epidemiological role and medical importance of this erythrovirus variant, a PCR assay is described that allows simultaneous detection of, and distinction between, erythrovirus B19 and the V9 isolate. Examination of 100 erythrovirus B19 IgM positive samples as well as plasma pools representing 100,000 Danish blood donor units for the presence of B19 and V9 DNA was performed. Despite the apparent absence of erythrovirus V9 in the clinical samples at present, the DNA sequence variability demonstrates that the erythrovirus group may be more divergent than thought previously and the child harboring this isolate may herald erythrovirus V9 as a possible emerging virus.
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Risberg B, Davidson B, Nielsen S, Dong HP, Christensen J, Johansen P, Asschenfeldt P, Berner A. Detection of monocyte/macrophage cell populations in effusions: a comparative study using flow cytometric immunophenotyping and immunocytochemistry. Diagn Cytopathol 2001; 25:214-9. [PMID: 11599103 DOI: 10.1002/dc.2041] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The objective of the present study was to compare the efficiency of immunophenotyping using flow cytometry (FCM) and immunocytochemistry (ICC) in the detection of macrophages in serous effusions. Cytoblock sections from 90 effusions were stained for the monocyte/macrophage marker CD14, using ICC. Fresh-frozen samples of all cases were analyzed for CD14 expression, using FCM. Epithelial, lymphoid, and mesothelial cell populations were identified using antibodies against Ber-EP4, CD45, and N-cadherin, respectively. Results were compared with clinical parameters and morphological diagnosis. Thirty-nine specimens were cytologically diagnosed as malignant, containing tumor cells of nonhematologic origin, whereas 46 were interpreted as benign. Two additional specimens were diagnosed as indeterminate or suspicious for malignancy, and 3 specimens contained lymphoma cells. CD14-positive cells were detected in 85/90 (94%) of effusions using FCM, and in all 90 specimens using ICC. The percentage of CD14-positive cells was highly variable, but in some specimens was as high as 76% using FCM and 85% using ICC. A good association was observed between the two methods in the detection of CD14-positive cells (P < 0.001). The presence of macrophages in effusions showed an association with female gender, using both FCM (P = 0.002) and ICC (P = 0.011), but none with effusion site, patient age, clinical and cytological diagnosis, or presence of Ber-EP4-positive cells (P > 0.05). The presence of Ber-EP4-positive cells showed a strong association with the cytological diagnosis of malignancy (P < 0.001). In conclusion, macrophages are a significant cell population in effusions, of both benign and malignant etiology, due to both their size and their possible confusion with cancer cells. Both FCM and ICC aid in the recognition of these cells, and thus provide an effective tool for the identification of different cell populations in effusions.
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Christensen J, Højskov CS, Dam M, Poulsen JH. Plasma concentration of topiramate correlates with cerebrospinal fluid concentration. Ther Drug Monit 2001; 23:529-35. [PMID: 11591899 DOI: 10.1097/00007691-200110000-00006] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The authors examined the ratio between the plasma and the cerebrospinal fluid (CSF) concentration of topiramate in 14 adults with epilepsy. Simultaneous trough samples of venous blood and CSF were collected and analyzed as total and unbound concentrations. Concomitant levels were also analyzed of lamotrigine (n = 5) and the relevant oxcarbazepine metabolite, 10-hydroxycarbazepine (n = 3). There was a close correlation between the plasma and the CSF concentration for both the total and unbound concentration of topiramate. The median CSF/plasma ratio of total topiramate was 0.85. The free topiramate concentration in plasma was not different from the free topiramate concentration in CSF. The CSF/plasma ratios showed little variation and were independent of the plasma level for both the total and the unbound levels. The unbound fraction of topiramate was 84% in plasma and 97% in CSF. The CSF concentrations of lamotrigine and 10-hydroxycarbazepine were 50% and 61% of the plasma concentrations, respectively. For topiramate, there is a close correlation between the plasma concentration and the CSF concentration. There does not seem to be a saturable carrier mechanism restricting topiramate transport across the blood-brain barrier. The concentration of topiramate in CSF is equal to the unbound proportion of topiramate in plasma, implying that the delivery of topiramate to the brain occurs via transfer from the unbound plasma pool. Plasma is thus a relevant matrix for therapeutic drug monitoring of topiramate.
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Chadfield M, Skov M, Christensen J, Madsen M, Bisgaard M. An epidemiological study of Salmonella enterica serovar 4, 12:b:- in broiler chickens in Denmark. Vet Microbiol 2001; 82:233-47. [PMID: 11470545 DOI: 10.1016/s0378-1135(01)00347-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Epidemiological investigations of isolates of Salmonella enterica serovar 4, 12:b:- were carried out to establish particular molecular markers to assign isolates to a common origin. Plasmid profiling demonstrated that over 50% of 291 isolates, obtained between 1991 and 1996, were plasmid-free. The remaining isolates exhibited a common trend in plasmid content of 105 and 2kb. Although no specific correlation to any particular source within the poultry industry was discernible using plasmid analysis, there were indications of clonality with local divergence. Ribotyping with EcoRI demonstrated limited discriminative potential as 96% of the isolates expressed a common profile. Ribotyping with HindIII failed to further differentiate the isolates. IS200 (PstI) typing and PFGE (NotI and XbaI) afforded some degree of further discrimination with selected isolates. Each technique produced four profiles, but dominant profiles were also apparent. Eighteen variables were selected for multivariate logistic regression analysis in order to identify risk areas associated with broiler flocks within the industry. An increased risk for S. 4, 12:b:- infection was only associated with the feedmills used. Random effects at the house and/or farm level were also found to be statistically significant. Of the 16 feedmills associated with the isolation of 4, 12:b:-, six were deemed to be significant risk factors.
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Mebius RE, Miyamoto T, Christensen J, Domen J, Cupedo T, Weissman IL, Akashi K. The fetal liver counterpart of adult common lymphoid progenitors gives rise to all lymphoid lineages, CD45+CD4+CD3- cells, as well as macrophages. THE JOURNAL OF IMMUNOLOGY 2001; 166:6593-601. [PMID: 11359812 DOI: 10.4049/jimmunol.166.11.6593] [Citation(s) in RCA: 190] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We identified an IL-7Ralpha(+)Sca-1(low)c-Kit(low) population in E14 fetal liver, which is the phenotypical analog of common lymphoid progenitors (CLP) in adult bone marrow. After transfer into newborn mice, the IL-7Ralpha(+)Sca-1(low)c-Kit(low) population rapidly differentiated into CD45(+)CD4(+)CD3(-) cells, which are candidate cells for initiating lymph node and Peyer's patch formation. In addition, this population also gave rise to B, T, NK, and CD8alpha(+) and CD8alpha(-) dendritic cells. The fetal liver precursors expressed a significantly lower level of the myeloid-suppressing transcription factor Pax-5, than adult CLP, and retained differentiation activity for macrophages in vitro. We propose that the transition from fetal liver IL-7Ralpha(+)Sca-1(low)c-Kit(low) cells to adult CLP involves a regulated restriction of their developmental potential, controlled, at least in part, by Pax-5 expression.
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Christensen J, Cotmore SF, Tattersall P. Minute virus of mice initiator protein NS1 and a host KDWK family transcription factor must form a precise ternary complex with origin DNA for nicking to occur. J Virol 2001; 75:7009-17. [PMID: 11435581 PMCID: PMC114429 DOI: 10.1128/jvi.75.15.7009-7017.2001] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Parvoviral rolling hairpin replication generates palindromic genomic concatemers whose junctions are resolved to give unit-length genomes by a process involving DNA replication initiated at origins derived from each viral telomere. The left-end origin of minute virus of mice (MVM), oriL, contains binding sites for the viral initiator nickase, NS1, and parvovirus initiation factor (PIF), a member of the emerging KDWK family of transcription factors. oriL is generated as an active form, oriL(TC), and as an inactive form, oriL(GAA), which contains a single additional nucleotide inserted between the NS1 and PIF sites. Here we examined the interactions on oriL(TC) which lead to activation of NS1 by PIF. The two subunits of PIF, p79 and p96, cooperatively bind two ACGT half-sites, which can be flexibly spaced. When coexpressed from recombinant baculoviruses, the PIF subunits preferentially form heterodimers which, in the presence of ATP, show cooperative binding with NS1 on oriL, but this interaction is preferentially enhanced on oriL(TC) compared to oriL(GAA). Without ATP, NS1 is unable to bind stably to its cognate site, but PIF facilitates this interaction, rendering the NS1 binding site, but not the nick site, resistant to DNase I. Varying the spacing of the PIF half-sites shows that the distance between the NS1 binding site and the NS1-proximal half-site is critical for nickase activation, whereas the position of the distal half-site is unimportant. When expressed separately, both PIF subunits form homodimers that bind site specifically to oriL, but only complexes containing p79 activate the NS1 nickase function.
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Christensen J, Balslev T, Villadsen J, Heinsvig EM, Dam M, Poulsen JH. Removal of 10-hydroxycarbazepine by plasmapheresis. Ther Drug Monit 2001; 23:374-9. [PMID: 11477319 DOI: 10.1097/00007691-200108000-00009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Removal of the oxcarbazepine metabolite 10-hydroxycarbazepine (MHD) by plasmapheresis was evaluated during a series of six plasmaphereses of a 13-year-old boy with Rasmussen encephalitis. Plasmapheresis was performed after steady-state concentrations of MHD had been achieved with a dose of 2550 mg oxcarbazepine daily. The mean amount of MHD removed per plasmapheresis was 78.9 mg (SD: 6.0 mg), representing 3% to 4% of the daily oxcarbazepine dose and approximately 5% to 6% of body stores of MHD. The mean steady-state trough MHD concentration was 33.3 mg/L (SD: 1.8 mg/L), and this was remarkably stable during the entire plasmapheresis period. The serum concentration of MHD was only mildly reduced by the procedure. The areas under the concentration curve of MHD on the first and sixth day of plasmapheresis were 99% and 94%, respectively, of the pre-plasmapheresis values. The results are in agreement with studies on other anticonvulsant medications (carbamazepine, valproic acid, phenobarbital, and phenytoin), indicating that minor fractions (2% to 10%) of body stores of these drugs are depleted during plasmapheresis. The authors conclude that it is unnecessary to adjust the oxcarbazepine dosage when performing single-volume plasma exchanges or even multiple exchanges during an extended period. It is further proposed that plasmapheresis is unlikely to be of therapeutic benefit in the treatment of an oxcarbazepine overdose.
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Traver D, Miyamoto T, Christensen J, Iwasaki-Arai J, Akashi K, Weissman IL. Fetal liver myelopoiesis occurs through distinct, prospectively isolatable progenitor subsets. Blood 2001; 98:627-35. [PMID: 11468160 DOI: 10.1182/blood.v98.3.627] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Hematopoietic fate maps in the developing mouse embryo remain imprecise. Definitive, adult-type hematopoiesis first appears in the fetal liver, then progresses to the spleen and bone marrow. Clonogenic common lymphoid progenitors and clonogenic common myeloid progenitors (CMPs) in adult mouse bone marrow that give rise to all lymphoid and myeloid lineages, respectively, have recently been identified. Here it is shown that myelopoiesis in the fetal liver similarly proceeds through a CMP equivalent. Fetal liver CMPs give rise to megakaryocyte-erythrocyte-restricted progenitors (MEPs) and granulocyte-monocyte-restricted progenitors (GMPs) that can also be prospectively isolated by cell surface phenotype. MEPs and GMPs generate mutually exclusive cell types in clonogenic colony assays and in transplantation experiments, suggesting that the lineage restriction observed within each progenitor subset is absolute under normal conditions. Purified progenitor populations were used to analyze expression profiles of various hematopoiesis-related genes. Expression patterns closely matched those of the adult counterpart populations. These results suggest that adult hematopoietic hierarchies are determined early in the development of the definitive immune system and suggest that the molecular mechanisms underlying cell fate decisions within the myeloerythroid lineages are conserved from embryo to adult. (Blood. 2001;98:627-635)
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Christensen J, Jaroszewski JW. Natural glycosides containing allopyranose from the passion fruit plant and circular dichroism of benzaldehyde cyanohydrin glycosides. Org Lett 2001; 3:2193-5. [PMID: 11440577 DOI: 10.1021/ol016044+] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[structure: see text] Leaves of the edible passion fruit plant, Passiflora edulis, contain benzylic beta-D-allopyranosides 1 and 2, representatives of a rare class of natural glycosides with D-allose as the only sugar constituent. The glycoside 1 is the first known cyanogenic glycoside containing a sugar different from D-glucose attached directly to the cyanohydrin center. Asymmetric perturbation of the (1)L(b) transition of the benzene chromophore was shown to be useful for determination of absolute configuration of the cyanohydrin center of aromatic cyanogenic glycosides.
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Nüesch JP, Christensen J, Rommelaere J. Initiation of minute virus of mice DNA replication is regulated at the level of origin unwinding by atypical protein kinase C phosphorylation of NS1. J Virol 2001; 75:5730-9. [PMID: 11390575 PMCID: PMC114289 DOI: 10.1128/jvi.75.13.5730-5739.2001] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Minute virus of mice nonstructural protein NS1 is a multifunctional protein that is involved in many processes necessary for virus propagation. To perform its distinct activities in timely coordinated manner, NS1 was suggested to be regulated by posttranslational modifications, in particular phosphorylation. In fact, NS1 replicative functions are dependent on protein kinase C (PKC) phosphorylation, most likely due to alteration of the biochemical profile of the viral product as determined by comparing native NS1 with its dephosphorylated counterpart. Through the characterization of NS1 mutants at individual PKC consensus phosphorylation sites for their biochemical activities and nickase function, we were able to identify two target atypical PKC phosphorylation sites, T435 and S473, serving as regulatory elements for the initiation of viral DNA replication. Furthermore, by dissociating the energy-dependent helicase activity from the ATPase-independent trans esterification reaction using partially single-stranded substrates, we could demonstrate that atypical PKC regulation of NS1 nickase activity occurs at the level of origin unwinding prior to trans esterification.
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Church JA, Mitchell WG, Gonzalez-Gomez I, Christensen J, Vu TH, Dimauro S, Boles RG. Mitochondrial DNA depletion, near-fatal metabolic acidosis, and liver failure in an HIV-infected child treated with combination antiretroviral therapy. J Pediatr 2001; 138:748-51. [PMID: 11343055 DOI: 10.1067/mpd.2001.112653] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A child with controlled human immunodeficiency virus infection presented with neurologic deterioration, lactic acidosis, and organic aciduria. Muscle biopsy revealed abnormal mitochondrial (mt) morphology, reduced mt enzyme activities, and mtDNA depletion. After adjustment of antiretroviral therapy to a regimen free of nucleoside analogs, marked improvement was seen in clinical status and mt abnormalities.
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Abstract
Definitions of epidemiological concepts regarding disease monitoring and surveillance can be found in textbooks on veterinary epidemiology. This paper gives a review of how the concepts: monitoring, surveillance, and disease control strategies are defined. Monitoring and surveillance systems (MO&SS) involve measurements of disease occurrence, and the design of the monitoring determines which types of disease occurrence measures can be applied. However, the knowledge of the performance of diagnostic tests (sensitivity and specificity) is essential to estimate the true occurrence of the disease. The terms, disease control programme (DCP) or disease eradication programme (DEP), are defined, and the steps of DCP/DEP are described to illustrate that they are a process rather than a static MO&SS.
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Nör JE, Christensen J, Liu J, Peters M, Mooney DJ, Strieter RM, Polverini PJ. Up-Regulation of Bcl-2 in microvascular endothelial cells enhances intratumoral angiogenesis and accelerates tumor growth. Cancer Res 2001; 61:2183-8. [PMID: 11280784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Vascular endothelial growth factor (VEGF) has been shown to be a potent mediator of angiogenesis that functions as a survival factor for endothelial cells by up-regulating Bcl-2 expression. We have recently reported that human dermal microvascular endothelial cells (HDMECs) seeded in biodegradable sponges and implanted into severe combined immunodeficient (SCID) mice organize into functional human microvessels that transport mouse blood cells. In this study, we implanted sponges seeded with OSCC-3 (oral squamous cell carcinoma) or SLK (Kaposi's sarcoma) together with endothelial cells into SCID mice to generate human tumors vascularized with human microvessels. This model system was used to examine the role of both endothelial cell Bcl-2 and the proangiogenic chemokine interleukin-8 (IL-8) on tumor growth and intratumoral microvascular density. Coimplantation of HDMECs overexpressing Bcl-2 (HDMEC-Bcl-2) and tumor cells resulted in a 3-fold enhancement of tumor growth when compared with the coimplantation of control HDMECs and tumor cells. This was associated with increased intratumoral microvascular density and enhanced endothelial cell survival. To determine whether the enhanced neovascularization mediated by Bcl-2 overexpression in endothelial cells was influenced by the synthesis of endogenous mediators of angiogenesis, we screened these cells for expression of VEGF, basic fibroblast growth factor (bFGF), and IL-8 by ELISA. HDMEC-Bcl-2 cells and VEGF-treated HDMECs exhibited a 15-fold and 4-fold increase, respectively, in the expression of the proangiogenic chemokine IL-8 in vitro, whereas the expression of VEGF and bFGF remained unchanged. Transfection of antisense Bcl-2 into HDMECs blocked VEGF-mediated induction of IL-8. Conditioned media from HDMEC-Bcl-2 induced proliferation and sprouting of endothelial cells in vitro and neovascularization in rat corneas. Anti-IL-8 antibody added to HDMEC-Bcl-2 conditioned media markedly reduced the potency of these responses. SCID mice bearing VEGF-producing tumor implants that were treated with anti-lL-8 antibody exhibited a 43% reduction in microvessel density and a 50% reduction in tumor weight compared with treatment with a nonspecific antibody. These results demonstrate that the up-regulation of Bcl-2 expression in endothelial cells that constitute tumor microvessels enhances intratumoral microvascular survival and density and accelerates tumor growth. Furthermore, endothelial cells that overexpress Bcl-2 have more angiogenic potential than control cells, and IL-8-neutralizing antibodies attenuate their angiogenic activity in vitro and in vivo.
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MESH Headings
- Animals
- Antibodies/pharmacology
- Carcinoma, Squamous Cell/blood supply
- Carcinoma, Squamous Cell/pathology
- Cell Division/physiology
- Cell Transplantation
- Disease Models, Animal
- Endothelium, Vascular/cytology
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/physiology
- Gene Expression Regulation
- Genes, bcl-2/genetics
- Humans
- Interleukin-8/antagonists & inhibitors
- Interleukin-8/biosynthesis
- Interleukin-8/immunology
- Mice
- Mice, SCID
- Mouth Neoplasms/blood supply
- Mouth Neoplasms/pathology
- Neoplasm Transplantation
- Neoplasms/blood supply
- Neoplasms/pathology
- Neovascularization, Pathologic/metabolism
- Neovascularization, Pathologic/pathology
- Proto-Oncogene Proteins c-bcl-2/biosynthesis
- Proto-Oncogene Proteins c-bcl-2/genetics
- Proto-Oncogene Proteins c-bcl-2/physiology
- Rats
- Sarcoma, Kaposi/blood supply
- Sarcoma, Kaposi/pathology
- Transplantation, Heterologous
- Up-Regulation
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White JR, Farukhi Z, Bull C, Christensen J, Gordon T, Paidas C, Nichols DG. Predictors of outcome in severely head-injured children. Crit Care Med 2001; 29:534-40. [PMID: 11373416 DOI: 10.1097/00003246-200103000-00011] [Citation(s) in RCA: 154] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVE Determine variables in the acute care period associated with survival and pediatric intensive care unit (PICU) length of stay (LOS) for children with severe traumatic brain injury. DESIGN Retrospective cohort. SETTING Level 1 pediatric trauma center. PATIENTS Children (0-17 yrs) admitted 1991 to 1995 with nonpenetrating traumatic brain injury and admission Glasgow Coma Scale score of <or=8. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS The first 72 hrs of hospitalization were analyzed in detail for 136 patients. The primary end point was survival; secondary end points were PICU LOS, cost, and day at which Glasgow Coma Scale score was >or=14. Predictors of outcome were abstracted, including Pediatric Trauma Score, Glasgow Coma Scale score, Pediatric Risk of Mortality, physiologic variables, computed tomography evidence of brain injury, and neuroresuscitative medications. The fatality rate was 24%. Age and gender were similar between groups (p >or= .1). Survival was independently predicted by 6-hr Glasgow Coma Scale score (odds ratio [OR] 4.6; 95% confidence interval [CI] 2.06-11.9; p < .001) and maximum systolic blood pressure (OR 1.05; 95% CI 1.01-1.09; p < .02). Odds of survival increased 19-fold when maximum systolic blood pressure was >or=135 mm Hg (OR 18.8; 95% CI 2.0-178.0; p < .01). By discharge, 67% of patients had an age-appropriate Glasgow Coma Scale score. Median hospital costs were 8,798 dollars for survivors: only mannitol use independently predicted high cost (odds ratio 4.9; 95% CI 1.2-19.1; p < .01). For survivors, median PICU LOS was 2 days, although 25% had LOS >6 days. Six-hour Glasgow Coma Scale score (OR 0.62; 95% CI 0.48-0.80; p < .001) and mannitol (OR 7.9; 95% CI 2.3-27.3; p < .001) were each independently associated with a prolonged LOS among survivors. CONCLUSIONS Patients with higher 6-hr Glasgow Coma Scale scores were more likely to survive. Adjusting for severity of injury, survival was associated with maximum systolic blood pressure >or=135 mm Hg, suggesting that supranormal blood pressures are associated with improved outcome. Mannitol administration was associated with prolonged LOS, yet conferred no survival advantage. We suggest reevaluation of blood pressure targets and mannitol use in children with severe traumatic brain injury.
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Holme SJ, Lund O, Christensen J, Fruergård KO, Abildgård U, Kassis E, Olesen A. [Coronary artery bypass without use of the heart-lung-machine]. Ugeskr Laeger 2001; 163:750-3. [PMID: 11228802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
INTRODUCTION Off pump coronary artery bypass via sternotomy (OPCAB) and via a small left anterior thoracotomy (MIDCAB) on the anterior coronary arteries of the heart was introduced at the present center in 1997. Starting this year we decided to increase OPCAB and MIDCAB to constitute at least 50% of CAB procedures including the posterior aspect of the heart. METHODS From January 1st through April 16th 1999 we performed 152 CAB procedures: 108 CABG, 6 MIDCAB, 13 OPCAB (on the anterior cornary arteries) and 25 OPCAB-Cx (including the circumflex artery). OP procedures were done using OCTOPUS-II to expose and stabilize the arteriotomies, and control angiography was performed before discharge. RESULTS Off pump CAB was performed in 2% of the first 50 CAB patients, 36% of the next 50 and 50% of the last 52. The CABG and OPCAB-Cx groups were comparable as regards degree of coronary artery disease and number of distal anastomoses, but differed as regards poor left ventricular function and unstable preoperative status. Early mortality was 1.9% in the CABG group and 0% in the OP groups. Control angiograms in the OP groups showed a patency from 92 to 100%. CONCLUSIONS In this short preliminary series, it was possible to increase the fraction of OP procedures to nearly 50% with good results.
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Hernandez B, Christensen J. Automatic external defibrillator intervention in the workplace. A comprehensive approach to program development. AAOHN JOURNAL : OFFICIAL JOURNAL OF THE AMERICAN ASSOCIATION OF OCCUPATIONAL HEALTH NURSES 2001; 49:96-106; quiz 107-8. [PMID: 11760271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
1. The planning and implementation of an automatic external defibrillator (AED) intervention in the workplace necessitates a comprehensive approach to program development. 2. Initiation of an AED intervention program at the worksite, based on an informed decision, requires each company to conduct a detailed assessment of need. 3. Prior to initiating an AED intervention program, appropriate resources should be consulted to examine national, state, and local law provisions and legal factors governing AED use in each specific community. 4. Essential components of an AED intervention program include: the combined cardiopulmonary resuscitation and AED use training program; written policies, procedures, and medical directives; a plan for the purchase, maintenance, and location of the AED equipment and supplies; an integrated emergency response plan; and an ongoing quality improvement process.
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Stege H, Christensen J, Nielsen JP, Willeberg P. Data-quality issues and alternative variable-screening methods in a questionnaire-based study on subclinical Salmonella enterica infection in Danish pig herds. Prev Vet Med 2001; 48:35-54. [PMID: 11150633 DOI: 10.1016/s0167-5877(00)00182-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Our aim was to determine risk factors for subclinical Salmonella enterica infection in Danish finishing-pig herds. In this paper, the evaluation, combining and initial reduction of variables is presented, along with assessment of the hypotheses in the preliminary statistical testing. The first group of herds was selected at random with no former knowledge of S. enterica infection. Both the herd prevalence and the within-herd prevalence among these herds turned out to be low; hence, some additional herds were selected from The Danish Salmonella Control program, based on their high seroprevalence. This resulted in a hybrid case-"control" design of the study and therefore, five different methods of categorising the data were used to ensure that variables were not wrongfully excluded as a result of using an improper design. Our questionnaire focused on management, infection-limiting precautions and feed and feeding procedures. To establish the prevalence of S. enterica infection within herds at the time of the visit, 50 blood samples from each herd were collected and serologically examined. The reliability of each variable from the questionnaire was assessed and it was decided which variables should be selected, disregarded, combined with other variables and/or recoded. In the simple statistical testing (2x2 tables, cut-off: P=0.25) herds were defined as subclinically S. enterica infected if the within-herd proportion of individual pigs with OD%>10 was more than 20%. The results included questionnaires from 96 randomly selected and 39 high-seroprevalence herds and 6814 blood samples. The initial 95 variables originally included in the questionnaires were reduced to 21 by critical check, combination, recoding and preliminary screening. We failed to demonstrate "herd size" as a risk factor for subclinical S. enterica infection in pig herds.
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Christensen J, Dantzer V. Panel discussion. Acta Vet Scand 2001. [DOI: 10.1186/1751-0147-42-s1-s95] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Staerk D, Christensen J, Lemmich E, Duus JO, Olsen CE, Jaroszewski JW. Cytotoxic activity of some phenanthroindolizidine N-oxide alkaloids from Cynanchum vincetoxicum. JOURNAL OF NATURAL PRODUCTS 2000; 63:1584-1586. [PMID: 11087617 DOI: 10.1021/np0003443] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Two previously known phenanthroindolizidine alkaloids, (-)-10beta-antofine N-oxide (1) and (-)-10beta, 13aalpha-14beta-hydroxyantofine N-oxide (2), and a novel alkaloid, (-)-10beta,13aalpha-secoantofine N-oxide (3), were isolated from aerial parts of Cynanchum vincetoxicum. Their structures were established by means of NMR methods, including COSY, NOESY, HSQC, and HMBC experiments, as well as from their CD spectra. Cytotoxic activity of the alkaloids was assessed in vitro using both a drug-sensitive KB-3-1 and a multi-drug-resistant KB-V1 cancer cell line. The antofine derivatives (1 and 2) showed pronounced cytotoxicity against the drug-sensitive cell line (IC(50) values about 100 nM), whereas the secoantofine derivative (3) was considerably less active. The KB-V1 cell line showed a marginal resistance against all alkaloids, demonstrating that these compounds are poor substrates for the P-glycoprotein (P-170) efflux pump.
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Ojeniyi B, Christensen J, Bisgaard M. Comparative investigations of Listeria monocytogenes isolated from a turkey processing plant, turkey products, and from human cases of listeriosis in Denmark. Epidemiol Infect 2000; 125:303-8. [PMID: 11117953 PMCID: PMC2869602 DOI: 10.1017/s0950268899004483] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Listeria monocytogenes was isolated from critical control points in a Danish turkey processing plant, from turkey products and from cases of human listeriosis. During processing in the plant the prevalence of L. monocytogenes ranged from 25.9 to 41.4%. Cleaning and disinfection decreased the prevalence to 6.4%. Isolates of L. monocytogenes were characterized by pulsed-field gel electrophoresis (PFGE) using restriction endonuclease ApaI. Identical DNA types were obtained from turkey products and the processing line even after cleaning and disinfection. Two identical DNA types were demonstrated among isolates from turkey products and human cases of listeriosis. The prevalence of L. monocytogenes in turkey products ranged from 7.3 to 17.4% for ready-to-eat products and raw products, respectively. Since none of the 27 flocks examined before slaughter sampled positive for L. monocytogenes and the prevalence increased during processing, the potential risk from turkey meat was apparently due to factory hygiene rather than intrinsic contamination of the turkeys.
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Staerk D, Lemmich E, Christensen J, Kharazmi A, Olsen CE, Jaroszewski JW. Leishmanicidal, antiplasmodial and cytotoxic activity of indole alkaloids from Corynanthe pachyceras. PLANTA MEDICA 2000; 66:531-536. [PMID: 10985079 DOI: 10.1055/s-2000-8661] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Five indole alkaloids, corynantheidine, corynantheine, dihydrocorynantheine, alpha-yohimbine and corynanthine were isolated from bark of Corynanthe pachyceras K. Schum. (Rubiaceae). The structures were established by spectroscopic methods, including previously unreported assignment of all 1H-NMR resonances by COSY and NOESY experiments. These and related alkaloids showed pronounced activity against Leishmania major promastigotes (IC50 at the micromolar level) but no significant in vitro antiplasmodial activity (against chloroquine-sensitive Plasmodium falciparum). Cytotoxicity assessed with drug sensitive KB-3-1 and multidrug-resistant KB-V1 cell lines was low; the alkaloids are apparently not substrates for the P-glycoprotein (P-170) efflux pump.
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Christensen J, Gardner IA. Herd-level interpretation of test results for epidemiologic studies of animal diseases. Prev Vet Med 2000; 45:83-106. [PMID: 10802335 DOI: 10.1016/s0167-5877(00)00118-5] [Citation(s) in RCA: 134] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Correct classification of the true status of herds is an important component of epidemiologic studies and animal disease-control programs. We review theoretical aspects of herd-level testing through consideration of test performance (herd-level sensitivity, specificity and predictive values), the factors affecting these estimates, and available software for calculations. We present new aspects and considerations concerning the effect of precision and bias in estimation of individual-test performance on herd-test performance and suggest methods (pooled testing, targeted sampling of subpopulations with higher prevalence, and use of combinations of tests) to improve herd-level sensitivity when the expected within-herd prevalence is low.
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Stege H, Christensen J, Nielsen JP, Baggesen DL, Enoe C, Willeberg P. Prevalence of subclinical Salmonella enterica infection in Danish finishing pig herds. Prev Vet Med 2000; 44:175-88. [PMID: 10760401 DOI: 10.1016/s0167-5877(00)00103-3] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Our aim was to determine the Salmonella enterica prevalence in 96 randomly selected Danish pig herds, based on serological examination of blood samples and bacteriological examination of faecal samples (collected simultaneously from the same pens). For comparison, 39 high-seroprevalence herds were included in the study. The representativeness of the selected herds was assessed, based on descriptive statistics of herd size and type. Totals of 1330 pen samples and 6814 blood samples were examined.The results from the meat-juice screening in the Danish S. enterica Control Programme were available for 3372 meat-juice samples from 91 of the 96 randomly selected herds and 1195 meat-juice samples from 37 of the 39 high-seroprevalence herds. Of the 96 randomly selected herds, 23 herds had no positive pen samples (out of 10), no positive blood samples (out of 50) and no positive meat-juice samples (out of approximately 30-40 samples in 6 months). Ten herds had one or more positive meat-juice samples but were otherwise negative. S. Typhimurium was isolated from 30 of the 39 high-seroprevalence herds. Our conclusions were: (1) The within-herd seroprevalence among the 96 randomly selected Danish pig herds was low (average within-herd seroprevalence=2%, maximum=32%). (2) Among the 39 high-seroprevalence herds (recently assigned level 3 in the S. enterica Control Programme), S. enterica was isolated from 77% of the herds when 10 pen samples were examined bacteriologically. (3) Seropositivity tended to be related to the presence of S. Typhimurium.
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Christensen J, Miftakhov R. Hiatus hernia: a review of evidence for its origin in esophageal longitudinal muscle dysfunction. Am J Med 2000; 108 Suppl 4a:3S-7S. [PMID: 10718444 DOI: 10.1016/s0002-9343(99)00288-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The axial forces exerted on the esophagus by the swallowing-induced contraction of its two longitudinally oriented muscle layers should, if unopposed, herniate the cardia through the diaphragm. A mathematical model of esophageal contraction shows that the magnitude of such a force becomes maximal just above the cardia, which is consistent with anatomic evidence of the existence of an inhibitory innervation in this same region. We propose that the inhibition exerted by these nerves when they discharge in swallowing prevents the supracardiac esophagus from shortening, allowing it to stretch and dissipating the pulling force of longitudinal muscle contraction above the diaphragm. Thus, hiatal hernia could originate from nerve disease, alteration in the viscoelastic properties of distal esophagus, or increased strength of the longitudinal muscle layers.
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Cotmore SF, Christensen J, Tattersall P. Two widely spaced initiator binding sites create an HMG1-dependent parvovirus rolling-hairpin replication origin. J Virol 2000; 74:1332-41. [PMID: 10627544 PMCID: PMC111468 DOI: 10.1128/jvi.74.3.1332-1341.2000] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Minute virus of mice (MVM) replicates via a linearized form of rolling-circle replication in which the viral nickase, NS1, initiates DNA synthesis by introducing a site-specific nick into either of two distinct origin sequences. In vitro nicking and replication assays with substrates that had deletions or mutations were used to explore the sequences and structural elements essential for activity of one of these origins, located in the right-end (5') viral telomere. This structure contains 248 nucleotides, most-favorably arranged as a simple hairpin with six unpaired bases. However, a pair of opposing NS1 binding sites, located near its outboard end, create a 33-bp palindrome that could potentially assume an alternate cruciform configuration and hence directly bind HMG1, the essential cofactor for this origin. The palindromic nature of this sequence, and thus its ability to fold into a cruciform, was dispensable for origin function, as was the NS1 binding site occupying the inboard arm of the palindrome. In contrast, the NS1 site in the outboard arm was essential for initiation, even though positioned 120 bp from the nick site. The specific sequence of the nick site and an additional NS1 binding site which directly orients NS1 over the initiation site were also essential and delimited the inboard border of the minimal right-end origin. DNase I and hydroxyl radical footprints defined sequences protected by NS1 and suggest that HMG1 allows the NS1 molecules positioned at each end of the origin to interact, creating a distortion characteristic of a double helical loop.
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Christensen J, Cotmore SF, Tattersall P. Two new members of the emerging KDWK family of combinatorial transcription modulators bind as a heterodimer to flexibly spaced PuCGPy half-sites. Mol Cell Biol 1999; 19:7741-50. [PMID: 10523663 PMCID: PMC84824 DOI: 10.1128/mcb.19.11.7741] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Initially recognized as a HeLa factor essential for parvovirus DNA replication, parvovirus initiation factor (PIF) is a site-specific DNA-binding complex consisting of p96 and p79 subunits. We have cloned and sequenced the human cDNAs encoding each subunit and characterized their products expressed from recombinant baculoviruses. The p96 and p79 polypeptides have 40% amino acid identity, focused particularly within a 94-residue region containing the sequence KDWK. This motif, first described for the Drosophila homeobox activator DEAF-1, identifies an emerging group of metazoan transcriptional modulators. During viral replication, PIF critically regulates the viral nickase, but in the host cell it probably modulates transcription, since each subunit is active in promoter activation assays and the complex binds to previously described regulatory elements in the tyrosine aminotransferase and transferrin receptor promoters. Within its recognition site, PIF binds coordinately to two copies of the tetranucleotide PuCGPy, which, remarkably, can be spaced from 1 to 15 nucleotides apart, a novel flexibility that we suggest may be characteristic of the KDWK family. Such tetranucleotides are common in promoter regions, particularly in activating transcription factor/cyclic AMP response element-binding protein (ATF/CREB) and E-box motifs, suggesting that PIF may modulate the transcription of many genes.
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DeZazzo J, Xia S, Christensen J, Velinzon K, Tully T. Developmental expression of an amn(+) transgene rescues the mutant memory defect of amnesiac adults. J Neurosci 1999; 19:8740-6. [PMID: 10516293 PMCID: PMC6782781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
The Drosophila memory gene amnesiac (amn) has been proposed to encode a neuropeptide protein, which includes regions homologous to vertebrate pituitary adenylyl cyclase-activating peptide (PACAP; Feany and Quinn, 1995). Definitive experiments to link this gene to memory formation, however, have not yet been accomplished (Kandel and Abel, 1995). The experiments described here demonstrate that the putative amn transcript is involved in adult memory formation. With the use of a UAS-amn(+) transgene, we show complete rescue of memory defects in amn(28A), a mutant allele caused by the insertion of a GAL4 enhancer trap transposon (Moore et al., 1998). Study of the amn(28A) reporter reveals widespread expression in the adult brain but also enriched expression in the embryonic and larval nervous systems. To begin addressing the temporal requirement of amn in memory, we asked whether the memory defects could be rescued by restricting transgenic expression to the adult stage. A heat-shock regimen shown previously to rescue fully the amn ethanol sensitivity defect (Moore et al., 1998) failed to rescue the memory defect. These results, coupled with previous genetic and anatomical studies, suggest that adult memory formation and ethanol sensitivity have different temporal and spatial requirements for amn.
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Miftakhov RN, Abdusheva GR, Christensen J. Numerical simulation of motility patterns of the small bowel. II. Comparative pharmacological validation of a mathematical model. J Theor Biol 1999; 200:261-90. [PMID: 10527717 DOI: 10.1006/jtbi.1999.0991] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A model of a locus of the small bowel, described earlier by the authors (Miftakhov et al., 1999) was validated in a comparison of the results of numerical simulations of pharmacological compounds to their effects in biological studies. The actions of the following four classes of drugs were simulated, those: (i) acting on the sarcoplasmic reticulum, (ii) altering the permeability of L- and T-type Ca(2+)channels on the smooth muscle membrane, (iii) motilides, and (iv) benzodiazepines. The strong qualitative resemblance between the theoretical and experimental results supports the robustness of the model.
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Josiassen MK, Christensen J. Change in lameness risk estimates in piglets due to the modelling of herd-level variation. Prev Vet Med 1999; 42:57-65. [PMID: 10532322 DOI: 10.1016/s0167-5877(99)00060-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In a previous study (Christensen, 1996. Prev. Vet. Med. 26, 107-118), an effect parameter changed from positive to negative depending on the model used. The study considered lameness in suckling piglets and the dataset included 7632 litters from 35 herds from the Health and Production Surveillance (HEPS) system database. To further investigate the change in the effect parameter, we performed a simple test to demonstrate the presence of herd-level variation. Finding substantial herd-level variation, we have re-analysed the data with special attention to the herd-level variation, and how to account for it. When herd-level variation was not accounted for in the model, a detrimental effect of prior treatment of the sow was seen but this turned into a beneficial effect when we accounted for the herd-level variation. The treatment of sow refers to any therapeutic treatment given to the sow after farrowing but before lameness or weaning occurred. This is, therefore, an example where not only the variances but also the effect parameters changed when we accounted for herd-level variation.
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McKenna R, Olson NH, Chipman PR, Baker TS, Booth TF, Christensen J, Aasted B, Fox JM, Bloom ME, Wolfinbarger JB, Agbandje-McKenna M. Three-dimensional structure of Aleutian mink disease parvovirus: implications for disease pathogenicity. J Virol 1999; 73:6882-91. [PMID: 10400786 PMCID: PMC112773 DOI: 10.1128/jvi.73.8.6882-6891.1999] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1998] [Accepted: 04/15/1999] [Indexed: 11/20/2022] Open
Abstract
The three-dimensional structure of expressed VP2 capsids of Aleutian mink disease parvovirus strain G (ADVG-VP2) has been determined to 22 A resolution by cryo-electron microscopy and image reconstruction techniques. A structure-based sequence alignment of the VP2 capsid protein of canine parvovirus (CPV) provided a means to construct an atomic model of the ADVG-VP2 capsid. The ADVG-VP2 reconstruction reveals a capsid structure with a mean external radius of 128 A and several surface features similar to those found in human parvovirus B19 (B19), CPV, feline panleukopenia virus (FPV), and minute virus of mice (MVM). Dimple-like depressions occur at the icosahedral twofold axes, canyon-like regions encircle the fivefold axes, and spike-like protrusions decorate the threefold axes. These spikes are not present in B19, and they are more prominent in ADV compared to the other parvoviruses owing to the presence of loop insertions which create mounds near the threefold axes. Cylindrical channels along the fivefold axes of CPV, FPV, and MVM, which are surrounded by five symmetry-related beta-ribbons, are closed in ADVG-VP2 and B19. Immunoreactive peptides made from segments of the ADVG-VP2 capsid protein map to residues in the mound structures. In vitro tissue tropism and in vivo pathogenic properties of ADV map to residues at the threefold axes and to the wall of the dimples.
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Christensen J, Sørensen JC, Ostergaard K, Zimmer J. Early postnatal development of the rat corticostriatal pathway: an anterograde axonal tracing study using biocytin pellets. ANATOMY AND EMBRYOLOGY 1999; 200:73-80. [PMID: 10395008 DOI: 10.1007/s004290050261] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
UNLABELLED The ontogenetic development of the neocortical projections to the striatum was studied in postnatal rats by sensitive anterograde tracing with biocytin. The developmental status of this mainly glutamatergic pathway is important as it plays a major role in regulation of striatal maturation and induction of excitotoxic striatal neurodegeneration resembling the type found in Huntington's disease. Biocytin pelletts were injected into the motorcortex caudal forelimb area of newborn rats and of rats aged 3, 6, 13, 27 and 61 days followed by sacrifice and visualisation of the tracer 24 h later, at P1, P7, P14, P28 and P62, respectively. Biocytin pellets were also injected into the motorcortex jaw-lip-tongue area and into the cingulate cortex of newborn and 6-day-old rats. The biocytin pellets produced intense anterograde labelling of corticofugal projection fibres from the injection sites, as well as a local Golgi-like labelling of neurons. From postnatal day 1 into adult age efferent fibres from the motorcortex caudal forelimb area displayed a progressively denser innervation of the ipsilateral and contralateral, dorsolateral striatum. The terminating fibres were most dense in the ipsilateral striatum. In the dorsolateral striatum the corticostriatal fibres displayed a patch/matrix-like arrangement from postnatal day 14 onwards. Injections into the motorcortex jaw-lip-tongue area at postnatal days 0 and 6 displayed a progressive, denser innervation of the ipsilateral and contralateral ventrolateral striatum. The cingulate corticostriatal fibre projection, was more developed at birth than the projection from the motorcortex and increased its fibre density in the ipsilateral dorsomedial striatum up to at least day 7. IN CONCLUSION the ipsilateral corticostriatal projections from the rat motorcortex and cingulate areas are present in newborn rats. During postnatal life the pathway develops further and specialisation of the terminating fibres into a patch/matrix like arrangement can be identified by postnatal day 14.
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Kuehl DW, Christensen J. Determination of Kow values for a series of aryl glucuronides. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 1999; 63:109-116. [PMID: 10423491 DOI: 10.1007/s001289900955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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246
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Christensen J, Baggesen DL, Soerensen V, Svensmark B. Salmonella level of Danish swine herds based on serological examination of meat-juice samples and Salmonella occurrence measured by bacteriological follow-up. Prev Vet Med 1999; 40:277-92. [PMID: 10423781 DOI: 10.1016/s0167-5877(99)00036-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Analyses of data collected in the Danish Salmonella Control Program in swine herds were conducted to assess the association between bacteriological and serological findings (including the degree to which changing serological status over time modulated the relationship) and to assess the degree to which type of swine operation and age group affected the relationship between bacteriological and serological findings. Although serological status was significantly associated with bacteriological prevalence of salmonella enterica in swine herds, the association was clarified by adding information on the change in serological status over time and the age group being tested. Salmonella infection assessed by serological tests at a single time-point and data on age group tested would allow better targeting and managing control programs.
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Petersen P, Olsen TS, Christensen J, Jørgensen HS. [Thrombolysis in acute apoplexy--more research is required]. Ugeskr Laeger 1999; 161:3111. [PMID: 10377859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Nyrop M, Bjerre PK, Christensen J, Jørgensen KE. Extensive and symptomatic cranial pneumatization: caused by frequent performance of Valsalva's manoeuvre? J Laryngol Otol 1999; 113:480-2. [PMID: 10505169 DOI: 10.1017/s0022215100144287] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Pneumocranium and spontaneous pneumocephalus are very rare disorders. We report a case in which the patient had suffered for some time from neck pain and neurological symptoms which originated from an extensively pneumatized cranium. The symptoms and the abnormal bone pneumatization disappeared after normalization of a high middle-ear pressure. The history and the findings suggest that the pathological pneumatization was caused by the patient's habit of frequently performing Valsalva's manoeuvre, in combination with the Eustachian tube functioning as a valve.
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Costello F, Steenfos N, Jensen KT, Christensen J, Gottschalck E, Holm A, Aasted B. Epitope mapping of Aleutian mink disease parvovirus virion protein VP1 and 2. Scand J Immunol 1999; 49:347-54. [PMID: 10219758 DOI: 10.1046/j.1365-3083.1999.00499.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Six overlapping fragments of the Aleutian Mink Disease parvoVirus (AMDV) virion protein VP1 and 2 (VP1/2) gene were inserted into the expression vector pMAL-c2. Four of the clones carried large overlapping fragments covering the entire VP1/2 gene. The remaining two clones covered specifically chosen regions within the VP1/2 gene. Using a Western blotting detection system, sera from AMDV-infected mink were tested against the recombinant polypeptides. These studies showed reactions primarily directed against the two AMDV polypeptides ranging from amino acids 297 to 518. Weaker reactions against other regions of the VP1/2 were also observed. The small fusion protein designed to cover the presumed AMDV VP1/2 loop 4 was purified by affinity chromatography and used to develop solid-phase immunoassays. Twelve small synthetic peptides were constructed and used as inhibitors. A peptide covering amino acids S428 to T448 was shown to block the reactivity of a pool of positive mink sera, indicating the presence of one dominant linear epitope.
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Christensen J, Akcasu N. The role of the pediatric nurse practitioner in the comprehensive management of pediatric oncology patients in the inpatient setting. J Pediatr Oncol Nurs 1999; 16:58-65; discussion 66-7. [PMID: 10331325 DOI: 10.1177/104345429901600202] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The role of the pediatric nurse practitioner (PNP) in the comprehensive management of pediatric oncology patients in the inpatient setting was examined at a large tertiary teaching hospital. This article shows role responsibilities including new diagnosis teaching, procedures, routine chemotherapy, patients' comprehensive medical management, coordination of nursing care across settings, phone triage, and professional development. A PNP's typical day is highlighted to illustrate the innovative merging of traditional ambulatory care roles with that of the PNP as a comprehensive manager of pediatric oncology patients in the inpatient setting. This role provides a more seamless care experience and provides critical links in the delivery of health care to pediatric oncology patients.
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