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Borregaard T, Nielsen H, Nørgaard L, Have H. Crop–weed Discrimination by Line Imaging Spectroscopy. ACTA ACUST UNITED AC 2000. [DOI: 10.1006/jaer.1999.0519] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Permin H, Nørgaard A, Norn S, Andersen LP, Nielsen H. IgE-mediated immune response to Helicobacter pylori examined by basophil histamine release in patients with dyspepsia. Inflamm Res 2000; 49 Suppl 1:S29-30. [PMID: 10864408 DOI: 10.1007/pl00000168] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Biering-Sørensen F, Schröder AK, Wilhelmsen M, Lomberg B, Nielsen H, Høiby N. Bacterial contamination of bath-water from spinal cord lesioned patients with pressure ulcers exercising in the water. Spinal Cord 2000; 38:100-5. [PMID: 10762183 DOI: 10.1038/sj.sc.3100964] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
AIM To evaluate the bacterial contamination of the water from the microflora of pressure ulcers in para- and tetraplegic patients, when they were exercising in water at 36 degrees C for half an hour. MATERIAL Twelve spinal cord lesioned (SCL) patients with ulcers participated, and six of the 12 SCL patients with healed ulcers constituted a control group. METHODS The evaluation was performed both with and without the ulcer covered with a moisture reactive occlusive dressing, DuoDERM. Bacterial samples were taken from the bath-water before and after the exercise programmes and additionally specimens were obtained from the ulcer, the patients skin and urine, and from the skin of the physiotherapist who exercised the patient. A similar procedure was carried out in the controls. RESULTS The bacteriologic analyses showed no significant difference in the contamination of the bath-water after exercising with or without DuoDERM covering the ulcers. In half of the patients DuoDERM loosened. After all exercise programmes with or without DuoDERM dressing the water was contaminated with facultative aerobic intestinal bacteria, ie E. faecalis and Enterobacteriaceae (E. coli, Klebsiella species, Proteus species, Enterobacter species). In nearly one-third of the exercise sessions the bath-water was contaminated with P. aeruginosa before starting, and after the exercise programmes one fourth of the ulcers were colonized with these pathogens. CONCLUSION The water specimen showed the bacteria from the intestine to be much more prominent than the bacteria coming from the ulcers. Thus the pressure ulcers were of minor importance for the bath-water and ought not to prohibit patients from the potential benefits of water exercise, but chlorination of the water in the training pool seems appropriate.
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Haugen P, Huss VA, Nielsen H, Johansen S. Complex group-I introns in nuclear SSU rDNA of red and green algae: evidence of homing-endonuclease pseudogenes in the Bangiophyceae. Curr Genet 1999; 36:345-53. [PMID: 10654088 DOI: 10.1007/s002940050509] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The green alga Scenedesmus pupukensis and the red alga Porphyra spiralis contain large group-IC1 introns in their nuclear small subunit ribosomal RNA genes due to the presence of open reading frames at the 5' end of the introns. The putative 555 amino-acid Scenedesmus-encoded protein harbors a sequence motif resembling the bacterial S9 ribosomal proteins. The Porphyra intron self-splices in vitro, and generates both ligated exons and a full-length intron RNA circle. The Porphyra intron has an unusual structural organization by encoding a potential 149 amino-acid homing-endonuclease-like protein on the complementary strand. A comparison between related group-I introns in the Bangiophyceae revealed homing-endonuclease-like pseudogenes due to frame-shifts and deletions in Porphyra and Bangia. The Scenedesmus and Porphyra introns provide new insights into the evolution and possible novel functions of nuclear group-I intron proteins.
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Hansen PS, Go MF, Varming K, Andersen LP, Graham DY, Nielsen H. Proinflammatory activation of neutrophils and monocytes by Helicobacter pylori is not associated with cagA, vacA or picB genotypes. APMIS 1999; 107:1117-23. [PMID: 10660142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Chronic Helicobacter pylori infection is associated with mucosal inflammation. The aim of the present study was to assess human neutrophil and monocyte activation induced by H. pylori strains with different virulence genotypes. Bacterial sonicates from 12 strains were used to induce phagocyte up-regulation of adherence molecule CD11b, assessed by fluorescence flow cytometry, and oxidative burst responses, assessed by chemiluminescence. A dose-dependent induction of the expression of CD11b was observed with sonicate from all H. pylori strains on both neutrophils and monocytes. Strains negative for cagA and picB genes had the same inducing activity of upregulation of CD11b as strains positive for these genes. A vacA-S2 type strain had the same activity as vacA-S1 type strains. The induction of toxic oxygen radicals by H. pylori-activated neutrophils gave higher median values for the cagA-positive strains than for the cagA-negative strains. For the monocyte chemiluminescence response, cagA-negative strains gave higher median values compared to cagA-positive strains. We conclude that upregulation of the neutrophil and monocyte adherence molecule CD11b induced by H. pylori sonicates is not associated with the presence of cagA, picB or mosaic pattern of vacA, and that cagA, picB-negative strains and vacA-S2 strains retain their inflammatory capacity.
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Nielsen H, Petersen AA, Skjødt H, Hørslev-Petersen K, Bendtzen K. Blood levels of CD11b+ memory T lymphocytes are selectively upregulated in patients with active rheumatoid arthritis. APMIS 1999; 107:1124-30. [PMID: 10660143 DOI: 10.1111/j.1699-0463.1999.tb01518.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The adhesion molecules CD11b (a beta2-integrin component) and CD54 (ICAM-1) on blood leukocytes were studied by flow cytometry in patients with rheumatoid arthritis (RA). The fractions of CD4+ cells co-expressing CD11b were elevated in 16 patients with active RA compared with those in 16 RA patients who improved during therapy and 8 healthy controls: 0.8+/-0.12% (mean+/-SEM) versus 0.3+/-0.06% (p<0.002) and 0.3+/-0.06% (p<0.005), respectively. Increased levels of CD11b+CD45R0+ cells were observed in patients with active RA compared to those with improved RA and controls: 12.6+/-3.9% versus 4.8+/-2.7% (p<0.002) and 6.1+/-1.2% (p<0.003), respectively. Disease activity, determined by C-reactive protein, correlated with the numbers of CD11b+CD45R0+ cells: r=0.62 (p<0.001). Seven patients were followed during induction of remission with methotrexate and glucocorticoids. The numbers of CD11b+CD4+ and CD11b+CD45R0+ cells fell significantly after clinical improvement. The levels of CD11b+CD14+ cells (monocytes) did not differ between the groups. The number of CD11b+CD15+ cells (neutrophils) was elevated in patients with RA irrespective of disease activity. The levels of CD54+ cells were not different between the RA and control groups. We conclude that the increased numbers of CD11b+ memory T cells may arise from exposure to stimuli outside the synovial compartment.
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Nielsen H, Lolk A, Andersen K, Andersen J, Kragh-Sørensen P. Characteristics of elderly who develop Alzheimer's disease during the next two years-a neuropsychological study using CAMCOG. The Odense Study. Int J Geriatr Psychiatry 1999; 14:957-63. [PMID: 10556867 DOI: 10.1002/(sici)1099-1166(199911)14:11<957::aid-gps43>3.0.co;2-b] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE The aim of the study was to determine which cognitive functions first deteriorate in Alzheimer's disease (AD) and to identify persons who would become demented 2 years following an initial examination. PARTICIPANTS A total of 2452 initially non-demented persons, aged 65-84 years and randomly drawn from the population, who were examined 2 years apart. MEASURES CAMCOG, the cognitive section of CAMDEX (The Cambridge Mental Disorders of the Elderly Examination). Fourteen composite measures were constructed of the 60 CAMCOG items. RESULTS During the 2-year period, 102 developed AD; this group had significantly lower scores on all of the 14 composite measures at baseline examination than the subjects who remained non-demented. The incident demented were significantly older than the non-demented, had less formal schooling, were more often unskilled and had lower verbal intellectual level. Logistic regression analyses showed that especially higher age, together with reduced recent and remote memory, low category verbal fluency and attentional deficiency, characterized incident demented 2 years before the diagnosis was made. CONCLUSIONS Cognitive changes, which develop years before the AD diagnosis, can be identified by means of CAMCOG, but this instrument does not allow identification of persons who later develop AD with sufficient precision.
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Penkowa M, Nielsen H, Hidalgo J, Bernth N, Moos T. Distribution of metallothionein I + II and vesicular zinc in the developing central nervous system: correlative study in the rat. J Comp Neurol 1999; 412:303-18. [PMID: 10441758 DOI: 10.1002/(sici)1096-9861(19990920)412:2<303::aid-cne9>3.0.co;2-g] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Because zinc (Zn) is a co-factor in enzymes and participates in neurotransmission, it is essential for brain development. However, because excess Zn may cause neuronal injury, cerebral mechanisms for Zn regulation must operate. The metallothionein isoforms I and II (MT I + II) are putative candidates for chelating unbound Zn released from Zn-containing nerve terminals or transported into the brain. Whether vesicular Zn and MT I + II occur in identical regions of the developing brain is unknown. Accordingly, the developmental distribution of MT I + II and vesicular Zn was mapped. By using double-labeling fluorescence histochemistry, MT I + II immunoreactivity (ir) was attributed to astrocytes and cells of myelomonocytic lineage. The cells of the myelomonocytic lineage shared the morphology of monocytes and macrophages but not of microglia and occurred primarily around vessels and ventricles in the brainstem. By contrast, astrocytes were widespread throughout the developing brain. In embryonic and neonatal brain, MT I + IIir astrocytes were almost selectively observed in the septum and fascia dentate hilus (hi) of the hippocampus. With increasing postnatal age, they also occurred in hippocampal cortex, basal forebrain, neocortex, cerebellar cortex, and cranial nerve nuclei. MT I + II mRNAs were detected in regions of the brain that also displayed MT I + IIir, indicating transcriptional events. Vesicular Zn was recorded in neonatal brain solely in the dentate hi of the hippocampus. With increasing age, the amount of vesicular Zn increased in the hippocampus and other forebrain regions. The presence of MT I + II proteins in the developing brain was confirmed by radioimmunoassay. The regional distribution of astrocytic MT I + IIir and vesicular Zn suggests that MT I + II are implicated in Zn metabolism in the developing forebrain.
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Kirk O, Lundgren JD, Pedersen C, Nielsen H, Gerstoft J. Can chemoprophylaxis against opportunistic infections be discontinued after an increase in CD4 cells induced by highly active antiretroviral therapy? AIDS 1999; 13:1647-51. [PMID: 10509565 DOI: 10.1097/00002030-199909100-00007] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND In the 'USPHS/IDSA Guidelines for Prevention of Opportunistic Infections in Persons Infected with Human Immunodeficiency Virus', the indications for chemoprophylaxis are based on nadir CD4 cell count. Many patients have, however, experienced an increase in CD4 cell count after the introduction of highly active antiretroviral therapy (HAART). OBJECTIVES To assess incidences of opportunistic infections after discontinuation of chemoprophylaxis in HIV-infected patients, who have experienced a HAART-induced increase in CD4 cell count. METHODS The Danish guidelines for chemoprophylaxis against opportunistic infections in HIV-infected patients were revised in late 1997, allowing discontinuation of chemoprophylaxis after initiation of HAART if the CD4 cell count remained above a specified limit for more than 6 months. Consecutive patients were followed, and incidences of opportunistic infections after discontinuation of chemoprophylaxis were assessed. RESULTS A total of 219 patients discontinued Pneumocystis carinii pneumonia (PCP)-chemoprophylaxis (12% maintenance therapy). One case of PCP was diagnosed within 174 person-years (PY) of follow-up, resulting in an incidence of 0.6 cases/100 PY follow-up (95% confidence interval, 0.0-3.2). No cases of cerebral toxoplasmosis, cytomegalovirus chorioretinitis, or disseminated Mycobacterium avium infection were observed. Follow-up time for these was, however, limited. CONCLUSION PCP-chemoprophylaxis can be safely discontinued after HAART-induced increase in CD4 cell count to more than 200 x 10(6) cells/l. Among consecutive patients who discontinue chemoprophylaxis according to well-defined guidelines, the observed incidence of PCP is below those reported earlier in patients with similar CD4 cell count.
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Kronborg Andersen C, Søgaard J, Hansen E, Kragh-Sørensen A, Hastrup L, Andersen J, Andersen K, Lolk A, Nielsen H, Kragh-Sørensen P. The cost of dementia in Denmark: the Odense Study. Dement Geriatr Cogn Disord 1999; 10:295-304. [PMID: 10364648 DOI: 10.1159/000017135] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
In a population-based study of dementia, the cost of care for 245 demented elderly and 490 controls matched by age and gender was estimated. Dementia of Alzheimer's type was diagnosed according to the NINCDS-ADRDA criteria, and vascular dementia and other types of dementia were diagnosed according to the DSM-IIIR criteria. Severity of dementia was determined by the Clinical Dementia Rating scale. The annual cost of medical care, domestic care, home help, nursing home and special equipment for nondemented patients was DKK 22,000 per person while the cost for very mildly, mildly, moderately and severely demented patients was DKK 49,000, DKK 93,000, DKK 138,000 and DKK 206,000, respectively. Except for very mild dementia the cost did not differ between elderly who suffer from Alzheimer's disease and those with other types of dementia. The net cost of dementia is the difference in cost between those with dementia and the matched controls and amounts on average to DKK 77,000 per person per year. However, priority setting cannot be based on the cost of dementia per se, but only on the cost of a specific dementia intervention compared to its health benefit.
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Bille M, Jensen AM, Kjaerbøl E, Vesterager V, Sibelle P, Nielsen H. Clinical study of a digital vs an analogue hearing aid. SCANDINAVIAN AUDIOLOGY 1999; 28:127-35. [PMID: 10384900 DOI: 10.1080/010503999424851] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Digital signal processing in hearing instruments has brought new perspectives to the compensation of hearing impairment and may result in alleviation of the adverse effects of hearing problems. This study compares a commercially available digital signal processing hearing aid (HA) (Senso) with a modern analogue HA with programmable fitting (Logo). The HAs tested are identical in appearance and, in spite of a different mode of operation, the study design ensured blinding of the test subjects. Outcome parameters were: improvements in speech recognition score in noise (deltaSRSN) with the HAs; overall preference for HA; overall satisfaction; and various measures of HA performance evaluated by a self-assessment questionnaire. A total of 28 experienced HA users with sensorineural hearing impairment were included and 25 completed the trial. No significant differences were found in deltaSRSN between the two HAs. Eleven subjects indicated an overall preference for the digital HA, 10 preferred the analogue HA and 4 had no preference. Concerning overall satisfaction, 8 subjects rated the digital HA superior to the analogue one, whereas 7 indicated a superior rating for the analogue HA and 10 rated the HAs equal. Acceptability of noise from traffic was the only outcome parameter which gave a significant difference between the HAs in favour of the digital HA. It is concluded that there are no significant differences in outcome between the digital and analogue signal processing HAs tested by these experienced HA-users.
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Cristóbal S, de Gier JW, Nielsen H, von Heijne G. Competition between Sec- and TAT-dependent protein translocation in Escherichia coli. EMBO J 1999; 18:2982-90. [PMID: 10357811 PMCID: PMC1171380 DOI: 10.1093/emboj/18.11.2982] [Citation(s) in RCA: 211] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Recently, a new protein translocation pathway, the twin-arginine translocation (TAT) pathway, has been identified in both bacteria and chloroplasts. To study the possible competition between the TAT- and the well-characterized Sec translocon-dependent pathways in Escherichia coli, we have fused the TorA TAT-targeting signal peptide to the Sec-dependent inner membrane protein leader peptidase (Lep). We find that the soluble, periplasmic P2 domain from Lep is re-routed by the TorA signal peptide into the TAT pathway. In contrast, the full-length TorA-Lep fusion protein is not re-routed into the TAT pathway, suggesting that Sec-targeting signals in Lep can override TAT-targeting information in the TorA signal peptide. We also show that the TorA signal peptide can be converted into a Sec-targeting signal peptide by increasing the hydrophobicity of its h-region. Thus, beyond the twin-arginine motif, the overall hydrophobicity of the signal peptide plays an important role in TAT versus Sec targeting. This is consistent with statistical data showing that TAT-targeting signal peptides in general have less hydrophobic h-regions than Sec-targeting signal peptides.
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Hansen PS, Go MF, Varming K, Andersen LP, Genta RM, Graham DY, Nielsen H. Proinflammatory activation of neutrophils and monocytes by Helicobacter pylori in patients with different clinical presentations. Infect Immun 1999; 67:3171-4. [PMID: 10338540 PMCID: PMC96641 DOI: 10.1128/iai.67.6.3171-3174.1999] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Chronic Helicobacter pylori infection is associated with mucosal inflammation. The aim of the present study was to assess human neutrophil and monocyte activation by H. pylori strains obtained from patients with different clinical presentations. Bacterial sonicates from 12 strains were used to stimulate phagocyte upregulation of CD11b/CD18 adherence molecules assessed by fluorescence flow cytometry and oxidative burst responses assessed by chemiluminescence. A dose-dependent activation of CD11b/CD18 adherence molecules was observed with all strains on both neutrophils and monocytes. The activities were similar for strains from patients with duodenal ulceration and for strains from asymptomatic volunteers irrespective of histopathologic grades of the biopsy specimens from the antral mucosa. The neutrophil chemiluminescence response correlated with histopathologic severity. We conclude that upregulation of neutrophil and monocyte adherence molecules by H. pylori sonicates is not associated with clinical presentation of the infection.
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Nielsen H, Kvinesdal B, Benfield TL, Lundgren JD, Konradsen HB. Rapid loss of specific antibodies after pneumococcal vaccination in patients with human immunodeficiency virus-1 infection. SCANDINAVIAN JOURNAL OF INFECTIOUS DISEASES 1999; 30:597-601. [PMID: 10225389 DOI: 10.1080/00365549850161160] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Pneumococcal infections are frequently observed in patients with human immunodeficiency virus (HIV) infection and active immunization has been recommended as prophylaxis in this patient group. We studied 103 out-patients with asymptomatic or mildly symptomatic HIV infection with respect to specific IgG and IgG2 pneumococcal antibodies before and after vaccination with a 23-valent pneumococcal polysaccharide vaccine. A significant increase ( > 2-fold) in IgG and IgG2 antibody levels was observed after 1 month in 69/103 patients (67%) with no correlation with the CD4 cell count at the time of vaccination. The response rate was not influenced by concurrent treatment with anti-retroviral monotherapy, or by age or gender. After immunization a strong correlation between IgG and IgG2 anti-pneumococcal antibodies was demonstrated. Nevertheless, 12 months after vaccination the specific antibody titres were not significantly different from pre-vaccination values. In conclusion, antibodies induced by pneumococcal vaccination in patients with HIV infection have a short duration. This raises the question as to whether vaccination will have any impact on clinical end-point in this group of patients.
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Emanuelsson O, Nielsen H, von Heijne G. ChloroP, a neural network-based method for predicting chloroplast transit peptides and their cleavage sites. Protein Sci 1999. [PMID: 16131659 DOI: 10.1110/(issn)1469-896x] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
We present a neural network based method (ChloroP) for identifying chloroplast transit peptides and their cleavage sites. Using cross-validation, 88% of the sequences in our homology reduced training set were correctly classified as transit peptides or nontransit peptides. This performance level is well above that of the publicly available chloroplast localization predictor PSORT. Cleavage sites are predicted using a scoring matrix derived by an automatic motif-finding algorithm. Approximately 60% of the known cleavage sites in our sequence collection were predicted to within +/-2 residues from the cleavage sites given in SWISS-PROT. An analysis of 715 Arabidopsis thaliana sequences from SWISS-PROT suggests that the ChloroP method should be useful for the identification of putative transit peptides in genome-wide sequence data. The ChloroP predictor is available as a web-server at http://www.cbs.dtu.dk/services/ChloroP/.
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Emanuelsson O, Nielsen H, von Heijne G. ChloroP, a neural network-based method for predicting chloroplast transit peptides and their cleavage sites. Protein Sci 1999; 8:978-84. [PMID: 10338008 PMCID: PMC2144330 DOI: 10.1110/ps.8.5.978] [Citation(s) in RCA: 1393] [Impact Index Per Article: 55.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
We present a neural network based method (ChloroP) for identifying chloroplast transit peptides and their cleavage sites. Using cross-validation, 88% of the sequences in our homology reduced training set were correctly classified as transit peptides or nontransit peptides. This performance level is well above that of the publicly available chloroplast localization predictor PSORT. Cleavage sites are predicted using a scoring matrix derived by an automatic motif-finding algorithm. Approximately 60% of the known cleavage sites in our sequence collection were predicted to within +/-2 residues from the cleavage sites given in SWISS-PROT. An analysis of 715 Arabidopsis thaliana sequences from SWISS-PROT suggests that the ChloroP method should be useful for the identification of putative transit peptides in genome-wide sequence data. The ChloroP predictor is available as a web-server at http://www.cbs.dtu.dk/services/ChloroP/.
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Minchiotti L, Kragh-Hansen U, Nielsen H, Hardy E, Mercier AY, Galliano M. Structural characterization, stability and fatty acid-binding properties of two French genetic variants of human serum albumin. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1431:223-31. [PMID: 10209294 DOI: 10.1016/s0167-4838(99)00026-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Four bisalbuminemic, unrelated persons were found in Bretagne, France, and their variant and normal albumins were isolated by DEAE ion exchange chromatography, reduced, carboxymethylated and treated with CNBr. Comparative two-dimensional electrophoresis of the CNBr digests showed that three of the variants were modified in fragment CB4, whereas the fourth had an abnormal fragment CB1. These fragments were isolated, digested with trypsin and mapped by reverse-phase HPLC. Sequencing of altered tryptic peptides showed that the three variants modified in CB4 were caused by the same, previously unreported, amino acid substitution: Asp314-->Val (albumin Brest). The fourth, however, was a proalbumin variant with the change Arg-2-->Cys (albumin Ildut). Both amino acid substitutions can be explained by point mutations in the structural gene: GAT-->GTT (albumin Brest) and CGT-->TGT (albumin Ildut). The proalbumin Ildut is very unstable and already in vivo it is to a large extent cleaved posttranslationally to Arg-Albumin and normal albumin. Furthermore, we observed that during a lengthy isolation procedure the remaining proalbumin was changed to Arg-Albumin or proalbumin lacking Arg-6. In addition, part of normal albumin had lost Asp1. Gas chromatographic investigations using isolated proteins indicated that albumin Brest has improved in vivo fatty acid-binding properties, whereas the structural modification(s) of albumin Ildut does not affect fatty acid binding.
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Hansen TM, Nielsen H, Bernth N, Moos T. Expression of ferritin protein and subunit mRNAs in normal and iron deficient rat brain. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1999; 65:186-97. [PMID: 10064889 DOI: 10.1016/s0169-328x(99)00011-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In non-neuronal tissue, ferritin subunit mRNAs are regulated by post-transcriptional mechanisms leading to decreased ferritin protein synthesis during iron deficiency. Biochemical studies have demonstrated that the cerebral ferritin concentration declines during iron deficiency, suggesting that expression of ferritin subunit mRNAs in the brain may be regulated by mechanisms similar to those of non-neuronal tissue. However, as ferritin expression has been only vaguely studied in brain, this hypothesis remains to be tested. We investigated the influence of dietary iron deficiency on the cellular distribution of ferritin protein using immunohistochemistry and H- and L-ferritin subunit mRNAs by non-radioactive in situ hybridization. Pregnant rats were subjected to an iron depleted diet (6.4 mg/kg) from the day of conception. Litters were kept on the same diet until euthanized at the postnatal age of 10 weeks. This treatment reduced brain iron levels from approximately 57 to 26 microgram/g. Reducing the iron stores reduced histochemical detectable iron and the expression of ferritin immunoreactivity in neurons, oligodendrocyte-like and microglia-like cells. In normal rats, H- and L-ferritin subunit mRNAs were expressed in virtually all neurons and non-neuronal cells. The cerebral expression of the ferritin subunit mRNAs was not affected by iron deficiency. The levels of ferritin subunit mRNAs in the brain were also unaltered from iron deficiency when examined by Northern blotting. In conclusion, brain levels of iron and ferritin protein are highly susceptible to dietary iron deficiency, whereas the cerebral expression of H- and L-ferritin subunit mRNAs remains unchanged.
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Rössel P, Schønheyder HC, Nielsen H. Fluconazole therapy in Candida albicans spondylodiscitis. SCANDINAVIAN JOURNAL OF INFECTIOUS DISEASES 1999; 30:527-30. [PMID: 10066061 DOI: 10.1080/00365549850161601] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
A case of Candida albicans spondylodiscitis in a 20-year-old female liver transplant recipient is reported. The patient was successfully treated with sequential therapy with liposomal amphotericin B and fluconazole. A review of the literature showed 10 cases of Candida albicans spondylodiscitis successfully treated either with fluconazole alone or a sequential therapy with amphotericin B and fluconazole. If long-term amphotericin B therapy is not feasible, a prolonged course of fluconazole in a daily dose of 200-400 mg may be considered as an alternative.
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Vader A, Nielsen H, Johansen S. In vivo expression of the nucleolar group I intron-encoded I-dirI homing endonuclease involves the removal of a spliceosomal intron. EMBO J 1999; 18:1003-13. [PMID: 10022842 PMCID: PMC1171192 DOI: 10.1093/emboj/18.4.1003] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The Didymium iridis DiSSU1 intron is located in the nuclear SSU rDNA and has an unusual twin-ribozyme organization. One of the ribozymes (DiGIR2) catalyses intron excision and exon ligation. The other ribozyme (DiGIR1), which along with the endonuclease-encoding I-DirI open reading frame (ORF) is inserted in DiGIR2, carries out hydrolysis at internal processing sites (IPS1 and IPS2) located at its 3' end. Examination of the in vivo expression of DiSSU1 shows that after excision, DiSSU1 is matured further into the I-DirI mRNA by internal DiGIR1-catalysed cleavage upstream of the ORF 5' end, as well as truncation and polyadenylation downstream of the ORF 3' end. A spliceosomal intron, the first to be reported within a group I intron and the rDNA, is removed before the I-DirI mRNA associates with the polysomes. Taken together, our results imply that DiSSU1 uses a unique combination of intron-supplied ribozyme activity and adaptation to the general RNA polymerase II pathway of mRNA expression to allow a protein to be produced from the RNA polymerase I-transcribed rDNA.
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Kirk O, Katzenstein TL, Gerstoft J, Mathiesen L, Nielsen H, Pedersen C, Lundgren JD. Combination therapy containing ritonavir plus saquinavir has superior short-term antiretroviral efficacy: a randomized trial. AIDS 1999; 13:F9-16. [PMID: 10207539 DOI: 10.1097/00002030-199901140-00002] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES To compare the efficacy and safety of indinavir 800 mg three times a day, ritonavir 600 mg twice a day, and a combination of ritonavir 400 mg twice a day and saquinavir 400 mg twice a day, when administered with two nucleoside analogues. DESIGN A randomized, open-labelled, controlled trial. Two hundred and eighty-four patients started randomized treatment. The primary end-point was the proportion of patients with HIV RNA of 200 copies/ml or less (Roche Amplicor) and HIV RNA of 20 copies/ml or less (Roche ultradirect assay) at 6 months. Analysis was performed as intent-to-treat, and missing values were accounted for as failures. RESULTS As of 1 May 1998, 269 patients should have completed 24 weeks of treatment. The proportion of patients with HIV RNA of 200 copies/ml or less was 71% (indinavir), 67% (ritonavir), and 82% (ritonavir + saquinavir), P = 0.07. In antiretroviral drug-naive patients (n = 119), the corresponding figures were 63, 57, and 89% (P < 0.01), whereas among drug-experienced patients (n = 165) 77, 74, and 77% had HIV RNA of 200 copies/ml or less (P = 0.90). The same pattern was observed in the ultradirect analysis. All three regimens were generally safe, but significantly more patients in the ritonavir group (37%) stopped treatment because of adverse drug reactions compared with the indinavir group (8%) and the ritonavir plus saquinavir group (16%) (P < 0.001). CONCLUSIONS Treatment with saquinavir plus ritonavir in combination with two nucleoside analogues is generally safe, and has superior short-term antiviral efficacy compared with indinavir and ritonavir also combined with two nucleoside analogues in antiretroviral drug-naive patients. Further follow-up is needed to determine the durability of the viral response.
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Andersen K, Nielsen H, Lolk A, Andersen J, Becker I, Kragh-Sørensen P. Incidence of very mild to severe dementia and Alzheimer's disease in Denmark: the Odense Study. Neurology 1999; 52:85-90. [PMID: 9921853 DOI: 10.1212/wnl.52.1.85] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE Calculation of incidence of dementia and AD, including cases in the earliest phases of the diseases. BACKGROUND Establishment of incidence estimates is important for the future planning of the health care system, and incidence studies can offer insights into risk factors. METHODS A total of 5,237 persons age 65 to 84 years were randomly drawn among people living in the municipality of Odense, Denmark. Of this sample 3,086 persons were eligible for the incidence study. All participants were examined with CAMCOG, the cognitive section of The Cambridge Examination for Mental Disorders of the Elderly (CAMDEX), and the follow-up period was 2 years. Using multiple linear regression, the CAMCOG cutoff score was individualized to detect even minor cognitive decline with optimal precision. Possibly demented persons were further examined with the remaining part of the CAMDEX and neuropsychological tests. AD was diagnosed according to National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria for probable AD, and vascular dementia and dementia of other types were diagnosed according to Diagnostic and Statistical Manual of Mental Disorders (3rd ed., revised) criteria for dementia. Finally, the severity of dementia was determined according to the Clinical Dementia Rating scale. RESULTS The incidence rate for very mild to severe dementia was 29.5 per 1,000 person-years and 20.9 for AD, and the rates were similar for men and women. CONCLUSION Application of an individualized cutoff for the screening instrument resulted in detection of a substantial number of cases with very mild dementia, which subsequently resulted in higher incidence rates than those reported in most other studies.
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Nielsen H, Brunak S, von Heijne G. Machine learning approaches for the prediction of signal peptides and other protein sorting signals. PROTEIN ENGINEERING 1999; 12:3-9. [PMID: 10065704 DOI: 10.1093/protein/12.1.3] [Citation(s) in RCA: 420] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Prediction of protein sorting signals from the sequence of amino acids has great importance in the field of proteomics today. Recently, the growth of protein databases, combined with machine learning approaches, such as neural networks and hidden Markov models, have made it possible to achieve a level of reliability where practical use in, for example automatic database annotation is feasible. In this review, we concentrate on the present status and future perspectives of SignalP, our neural network-based method for prediction of the most well-known sorting signal: the secretory signal peptide. We discuss the problems associated with the use of SignalP on genomic sequences, showing that signal peptide prediction will improve further if integrated with predictions of start codons and transmembrane helices. As a step towards this goal, a hidden Markov model version of SignalP has been developed, making it possible to discriminate between cleaved signal peptides and uncleaved signal anchors. Furthermore, we show how SignalP can be used to characterize putative signal peptides from an archaeon, Methanococcus jannaschii. Finally, we briefly review a few methods for predicting other protein sorting signals and discuss the future of protein sorting prediction in general.
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Madsen JK, Pedersen F, Nielsen H, Jensen GV, Hansen JF. Improvement in long-term prognosis of elderly patients with acute myocardial infarction after the introduction of intravenous thrombolytic therapy. Scand Cardiovasc J Suppl 1998; 32:365-70. [PMID: 9862099 DOI: 10.1080/14017439850139825] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Survival rate from a "thrombolytic" period of 351 patients above 66 years of age with acute myocardial infarction (AMI) was compared with that of 289 patients from a "prethrombolytic" period. The two groups were comparable regarding sex, age, previous AMI, cerebrovascular events, morbidity and mortality during admission. Survival rates after four years were 45.0% in the "thrombolytic" group and 38.4% in the "prethrombolytic" group (p = 0.047, log rank test). Using the Cox proportional hazard analysis, thrombolytic therapy was shown to be an independent prognostic predictor in "the thrombolytic population" with a relative risk of death from day 30 to end of follow-up of 0.4 (95% confidence interval 0.2-0.8). No interaction was found between age and thrombolysis. Although only one-fifth of the patients with AMI were eligible for thrombolysis, this treatment may have contributed to the improved long-term survival.
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