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J Jacobsen

Publications and source records attributed to J Jacobsen.

At least 19 recordsLinked to original sources
PubMed2006

Limits on the high-energy gamma and neutrino fluxes from the SGR 1806-20 giant flare of 27 December 2004 with the AMANDA-II detector.

On 27 December 2004, a giant gamma flare from the Soft Gamma-Ray Repeater 1806-20 saturated many satellite gamma-ray detectors, being the brightest transient event ever observed in the Galaxy. AMANDA-II was used to search for down-going muons indicative of high-energy gammas and/or neutrinos from this object. The data revealed no significant signal, so upper limits (at 90% C.L.) on the normalization constant were set: 0.05(0.5) TeV-1 m;{-2} s;{-1} for gamma=-1.47 (-2) in the gamma flux and 0.4(6.1) TeV-1 m;{-2} s;{-1} for gamma=-1.47 (-2) in the high-energy neutrino flux.

Journal Article↗
PubMed2006

Newer cyclo-oxygenase-2 selective inhibitors, other non-steroidal anti-inflammatory drugs and the risk of acute pancreatitis.

BACKGROUND: Case reports have suggested that the use of newer cyclo-oxygenase-2 selective inhibitors may cause acute pancreatitis, but there has been no formal study of the association. AIM: To assess the relationship between the use of cyclo-oxygenase-2 inhibitors and other non-steroidal anti-inflammatory drugs, and risk of acute pancreatitis. METHODS: A population-based case-control study was conducted using hospital discharge and prescription data from Denmark. Using conditional logistic regression with adjustment for multiple covariates, we estimated the relative risk of acute pancreatitis for use of the cyclo-oxygenase-2 inhibitors celecoxib and rofecoxib and for other non-steroidal anti-inflammatory drugs. RESULTS: A total of 3083 cases of acute pancreatitis and 30 830 population controls were identified. For current use the relative risk estimate for celecoxib was 1.4 (95% CI: 0.8-2.3) and for rofecoxib was 1.3 (95% CI: 0.7-2.3). The overall relative risk for other non-steroidal anti-inflammatory drugs was 2.7 (95% CI: 2.4-3.0) with a substantial variation in risk between the individual drugs. The highest relative risk was for diclofenac (odds ratio 5.0, 95% CI: 4.2-5.9) and the lowest for naproxen (odds ratio 1.1, 95% CI: 0.7-1.7). CONCLUSION: Cyclo-oxygenase-2 selective inhibitors are associated with a lower risk of acute pancreatitis than most other non-steroidal anti-inflammatory drugs.

Acute Disease↗
PubMed2006

Statins and the risk of acute pancreatitis: a population-based case-control study.

BACKGROUND: Case reports have suggested that statins may cause acute pancreatitis. AIM: To examine if statins are associated with risk of acute pancreatitis. METHODS: We identified 2576 first-time admitted cases of acute pancreatitis from hospital discharge registers in three Danish counties, and 25 817 age- and gender-matched controls from the general population. Prescriptions for statins prior to admission with acute pancreatitis or index date among controls were retrieved from prescription databases. We used conditional logistic regression analysis to estimate odds ratios for acute pancreatitis among ever (ever before), current (0-90 days before), new (first prescription in 0-90 days before) and former (>90 days, but not 0-90 days before) users of statins. RESULTS: Adjusted odds ratios for acute pancreatitis among ever, current, new and former users of statins were 1.44 (95% confidence interval: 1.115-1.80), 1.26 (95% confidence interval: 0.96-1.64), 1.01 (95% confidence interval: 0.43-2.37) and 2.02 (95% confidence interval: 1.37-2.97), respectively. There was an indication of an inverse association between the number of filled prescriptions and risk of acute pancreatitis. CONCLUSIONS: Our findings speak against a strong causative effect of statins on the risk of acute pancreatitis, and may even indicate a mild protective effect.

Acute Disease↗
PubMed2006

Rising incidence and persistently high mortality of hospitalized pneumonia: a 10-year population-based study in Denmark.

BACKGROUND: Little is known about temporal trends in the incidence and mortality of pneumonia in the general population. METHODS: We conducted a population-based cohort study in three Danish counties (population 1.4 million) to examine changes in the incidence and 30- and 90-day mortality associated with hospitalized pneumonia between 1994 and 2004. All adults hospitalized with a first-time diagnosis of pneumonia (n = 41 793) were identified in hospital discharge registries and followed for mortality through the Danish Civil Registry System. We determined age-standardized incidence rates and adjusted mortality rates associated with calendar year, gender, age and comorbidity. RESULTS: Between 1994 and 2003, the incidence of hospitalized pneumonia amongst adults increased from 288 per 100 000 person-years to 442 per 100 000 person-years, equivalent to an age-standardized incidence rate ratio of 1.50. The cumulative mortality within 30 and 90 days of admission was 15.2% and 21.9%, respectively, ranging from a 90-day mortality of 2.5% in patients aged 15-39 years to 34.7% in those aged 80 and over. Advanced age was the most important poor prognostic factor, followed by a high comorbidity score and male gender. The adjusted mortality rate ratios amongst patients with hospitalized pneumonia in 1999-2004, when compared with 1994-1998, were 0.89 (95% CI 0.85-0.94) after 30 days and 0.91 (95% CI 0.88-0.95) after 90 days. CONCLUSIONS: The incidence of hospitalized pneumonia in Denmark has increased considerably during the last 10 years and, combined with persistently high mortality rates, is of clinical and public health concern.

Adolescent↗
PubMed2006

Improved survival of patients with ovarian cancer in Northern Denmark, 1985-2004.

OBJECTIVE: Ovarian cancer is a serious disease with a high mortality. Our aim was to examine changes in the survival of patients with ovarian cancer in Northern Denmark. STUDY DESIGN AND SETTING: Patients (no. = 3,719) with an incident discharge diagnosis of ovarian cancer (1985-2004) from any hospital in four Danish counties (population, 1.6 million) were included and tracked for mortality through the Danish Civil Registration System. We determined survival and mortality rates stratified by age, and used Cox proportional hazard regression analyses to assess changes over time. RESULTS: Overall survival rate improved between 1985 and 2004. One-year survival increased from 61% to 73%, and five-year survival from 30% to 38%. Compared with the period 1985-1989 the age-adjusted one-year mortality rate ratio (MRR) was 0.65 (2000-2004) and the age-adjusted five-year MRR was 0.80 (1995-1999). The improvement was most pronounced in patients older than 40 years. CONCLUSION: The survival of ovarian cancer patients has improved in Denmark in recent decades. This change may be the result of improved treatment.

Aged↗
PubMed2005

Metronidazole and risk of acute pancreatitis: a population-based case-control study.

BACKGROUND: Use of metronidazole has been suggested to be associated with an increased risk of acute pancreatitis in case reports. AIM: To examine this issue within a proper epidemiological design. METHODS: We identified 3083 incident cases of acute pancreatitis from Hospital Discharge Registries in three Danish counties and 30 830 matched population controls. From prescription databases, we extracted information on use of metronidazole with or without concomitant use of proton-pump inhibitors and/or amoxicillin, macrolides or tetracycline. RESULTS: Adjusted odds ratios for acute pancreatitis in study subjects who redeemed a prescription for metronidazole within 30, 31-180, or 181-365 days before hospitalization or index date among controls were 3.0 [95% confidence interval (CI): 1.4-6.6], 1.8 (95% CI: 1.2-2.9) and 1.1 (95% CI: 0.6-1.8), respectively. Among subjects with a concomitant prescription for proton-pump inhibitors and/or amoxicillin, macrolides or tetracycline within 30, 31-180, or 181-365 days before hospitalization, or index date among controls, adjusted odds ratios were 8.3 (95% CI: 2.6-26.4), 2.7 (95% CI: 1.4-5.5), and 1.7 (95% CI: 0.6-4.8), respectively. CONCLUSION: Metronidazole may increase the risk of acute pancreatitis. However, the risk seems mainly to increase when metronidazole is used in combination with other drugs used for Helicobacter pylori eradication.

Acute Disease↗
PubMed2004

The risk of congenital abnormalities in children fathered by men treated with azathioprine or mercaptopurine before conception.

BACKGROUND: Immunosuppressive therapy with azathioprine and mercaptopurine is commonly used in patients with various chronic diseases. The few existing data on the reproductive safety of these drugs after paternal use before conception are inconclusive. AIM: To examine the risk of congenital abnormalities in children fathered by men exposed to azathioprine or mercaptopurine before conception. METHODS: This was a Danish population-based cohort study, based on data from the Prescription Database, the Medical Birth Registry and the Hospital Discharge Registry of North Jutland County, Denmark. Fifty-four exposed pregnancies, in which the father filed a prescription for azathioprine or mercaptopurine (between 1 January 1991 and 31 December 2001) before conception, were included. The controls comprised 57 195 pregnancies with no paternal azathioprine or mercaptopurine use. RESULTS: Four children with congenital abnormalities (underlying paternal diseases: glomerulonephritis and severe skin disease) were found in 54 exposed pregnancies (7.4%), compared with 2334 (4.1%) in controls. The adjusted odds ratio for congenital abnormalities in children fathered by men treated with azathioprine or mercaptopurine was 1.8 (95% confidence interval, 0.7-5.0). CONCLUSIONS: Our data may indicate that paternal use of azathioprine or mercaptopurine before conception is associated with an increased risk of congenital abnormalities. However, more data are needed to determine whether the association is causal.

Abnormalities, Drug-Induced↗
PubMed2004

Search for extraterrestrial point sources of neutrinos with AMANDA-II.

We present the results of a search for point sources of high-energy neutrinos in the northern hemisphere using AMANDA-II data collected in the year 2000. Included are flux limits on several active-galactic-nuclei blazars, microquasars, magnetars, and other candidate neutrino sources. A search for excesses above a random background of cosmic-ray-induced atmospheric neutrinos and misreconstructed downgoing cosmic-ray muons reveals no statistically significant neutrino point sources. We show that AMANDA-II has achieved the sensitivity required to probe known TeV gamma-ray sources such as the blazar Markarian 501 in its 1997 flaring state at a level where neutrino and gamma-ray fluxes are equal.

Journal Article↗
PubMed2004

Expression of vascular endothelial growth factor protein in human renal cell carcinoma.

OBJECTIVE: To evaluate the effect of vascular endothelial growth factor (VEGF, one of the most important angiogenetic factors) in renal cell carcinoma (RCC) by analysing many RCCs for the expression of immunohistochemical (IHC) VEGF-staining related to clinicopathological findings and survival. PATIENTS AND METHODS: VEGF immunostaining was examined with the tissue microarray (TMA) method on tumour samples from 229 patients and validated in 71 by ordinary tissue sections (TS). IHC VEGF expression was quantified by estimating the volume density and staining intensity on a three-grade scale. RESULTS: In most RCCs there was VEGF staining in the cell cytoplasm and membrane. In cell membranes the VEGF expression declined with storage time. IHC VEGF expression analysed by TMA and TS gave corresponding results. There was no difference in VEGF expression among conventional, papillary and chromophobe RCCs. There were significant correlations between VEGF expression and tumour size and stage. In univariate analysis VEGF expression correlated with survival, especially in conventional RCCs; this prognostic information was lost in multivariate analysis. The VEGF staining intensity correlated only with VEGF expression but not with any clinicopathological factors. CONCLUSIONS: VEGF protein was present in most RCC cells. There was no difference in VEGF expression among the different RCC types. The correlation between VEGF expression and tumour stage and with prognosis indicates the significance of VEGF within tumour growth and progression in RCC.

Adult↗
PubMed2003

Comparison of Agrobacterium-mediated transformation of four barley cultivars using the GFP and GUS reporter genes.

Experiments were conducted to produce transgenic barley plants following infection of immature embryos with Agrobacterium tumefaciens. Transformed callus was obtained using hygromycin resistance as a selectable marker and either green fluorescent protein (GFP) or beta-glucuronidase (GUS) as a reporter. Significantly reduced plant transformation frequencies were obtained with the GFP gene compared to GUS. However, GFP proved to be an excellent reporter of early transformation events and was used to compare four barley cultivars for efficiency in two phases of transformation: the generation of stably transformed barley callus and the regeneration of plantlets from transformed callus. Transformed callus was generated at a high frequency (47-76%) in all four cultivars. Regeneration of transformed plantlets was also achieved for all four cultivars although the frequency was much higher for Golden Promise than for the other three genotypes, reiterating that genotype is an important determinant in the regenerative ability of barley. This study has demonstrated for the first time that Agrobacterium-mediated transformation can be used to transform the Australian cultivars Sloop and Chebec.

Agrobacterium tumefaciens↗
PubMed2003

Limits on diffuse fluxes of high energy extraterrestrial neutrinos with the AMANDA-B10 detector.

Data from the AMANDA-B10 detector taken during the austral winter of 1997 have been searched for a diffuse flux of high energy extraterrestrial muon neutrinos. This search yielded no excess events above those expected from background atmospheric neutrinos, leading to upper limits on the extraterrestrial neutrino flux measured at the earth. For an assumed E-2 spectrum, a 90% classical confidence level upper limit has been placed at a level E2Phi(E)=8.4 x 10(-7) cm(-2) s(-1) sr(-1) GeV (for a predominant neutrino energy range 6-1000 TeV), which is the most restrictive bound placed by any neutrino detector. Some specific predicted model spectra are excluded. Interpreting these limits in terms of the flux from a cosmological distributions of sources requires the incorporation of neutrino oscillations, typically weakening the limits by a factor of 2.

Journal Article↗
PubMed2003

Prevalence of impaired left ventricular systolic function and heart failure in a middle aged and elderly urban population segment of Copenhagen.

OBJECTIVE: To assess the prevalence of impaired left ventricular systolic function and manifest heart failure in a general population aged 50-89 years. DESIGN: In this cross sectional survey, participants filled in a heart failure questionnaire. ECG, blood tests, and echocardiography were performed. SETTING: The study population was recruited from general practitioners situated in the same urban area and examined in a university hospital in Copenhagen, Denmark. PARTICIPANTS: 764 participants (432 women and 332 men, median (SD) age 66 (11) years) participated. The study population was stratified to include a minimum of 150 persons in each age decade. MAIN OUTCOME MEASURES: Prevalence of impaired systolic function and manifest heart failure. RESULTS: The prevalence of systolic dysfunction (left ventricular ejection fraction < or = 40%) was more than twice as high among men (7.6%) as among women (2.6%). In the male population systolic heart failure (left ventricular ejection fraction < or = 40% and symptoms) was found in 1.8% of the 50-59 years age group and approximately doubled for each age decade to reach 13.9% in octogenarians. Among women systolic dysfunction increased from 0.8% to 4.3% in the same age groups. Asymptomatic cases accounted for 44.0% of all cases of systolic dysfunction in the male population and only 9.1% in the female population. CONCLUSIONS: In this age controlled population study impaired left ventricular systolic function and heart failure increased substantially with age and was more than twice as frequent among men as among women. Asymptomatic left ventricular dysfunction occurred more frequently in men than in women and was less prevalent with increasing age.

Age Factors↗
PubMed2002

Prognostic importance of serum vascular endothelial growth factor in relation to platelet and leukocyte counts in human renal cell carcinoma.

It has been shown that both serum vascular endothelial growth factor (VEGF) and also platelet counts are associated with survival in renal cell carcinoma (RCC). It is not known, however, whether VEGF in serum relates to the angiogenic activity of the tumour or is derived from circulating blood components. Therefore, the interrelation between serum VEGF, platelet and leukocyte counts compared with health history, clinicopathological findings and outcome was evaluated in patients with RCC. Blood samples were collected before nephrectomy in 161 patients. Serum VEGF165 was assessed by a quantitative ELISA method. Platelet and leukocyte counts were analysed routinely and obtained from medical records. The variables were compared using univariate and multivariate analysis. There were significant correlations between VEGF levels, and platelet (P < 0.001) and leukocyte counts (P < 0.001). Serum VEGF levels, platelet counts, as well as leukocyte counts correlated significantly to stage and grade. Platelet counts were significantly lower in men with medication (P = 0.042), and decreased with age particularly in women (P = 0.001). Age or medication did not affect VEGF levels or leukocyte counts. Both VEGF and platelets gave significant prognostic information in univariate analysis. Using Cox multivariate analysis, VEGF was the last variable to be excluded. Only stage and grade remained as independent prognostic factors. Both VEGF levels and platelet counts gave prognostic information but VEGF was more reliable as predictor of survival in patients with RCC.

Adult↗
PubMed2001

Observation of high-energy neutrinos using Cerenkov detectors embedded deep in Antarctic ice.

Neutrinos are elementary particles that carry no electric charge and have little mass. As they interact only weakly with other particles, they can penetrate enormous amounts of matter, and therefore have the potential to directly convey astrophysical information from the edge of the Universe and from deep inside the most cataclysmic high-energy regions. The neutrino's great penetrating power, however, also makes this particle difficult to detect. Underground detectors have observed low-energy neutrinos from the Sun and a nearby supernova, as well as neutrinos generated in the Earth's atmosphere. But the very low fluxes of high-energy neutrinos from cosmic sources can be observed only by much larger, expandable detectors in, for example, deep water or ice. Here we report the detection of upwardly propagating atmospheric neutrinos by the ice-based Antarctic muon and neutrino detector array (AMANDA). These results establish a technology with which to build a kilometre-scale neutrino observatory necessary for astrophysical observations.

Journal Article↗
PubMed2001

Buccal iontophoretic delivery of atenolol.HCl employing a new in vitro three-chamber permeation cell.

The present work showed that the iontophoretic approach was feasible to enhance buccal drug delivery. A new in vitro horizontal three-chamber iontophoretic permeation cell has been developed to reflect the in vivo iontophoretic drug delivery more closely, electrodes were positioned on the epithelial side in separate chambers. Iontophoretic delivery of atenolol.HCl across porcine buccal mucosa increased proportional to (a) increased initial donor concentration in the range of 0.027 M to 0.10 M atenolol.HCl, (b) increased "on time" of current on/off ratio valued 50/50, 75/25 and 90/10 resulting in enhancement ratios 19, 58, and 112 respectively, initially applying 0.10 M atenolol.HCl and (c) increased current density valued 0.1, 0.2, 0.3, and 0.4 mA/cm(2) obtaining enhancement ratios 6, 18, 36, and 58 respectively, initially applying 0.10 M atenolol.HCl. Microscopy of hematoxyilin-eosin stained sections of porcine buccal mucosae conducting 8-h passive permeation showed minute morphological alterations whereas 8-h iontophoretic treatment showed disordering of the outer epithelial cell layers, alterations being more pronounced in mucosae from reference chambers than donor chambers. The results demonstrated the feasibility of the iontophoretic approach to enhance and control the rate of buccal drug delivery, hence the usefulness of the new permeation cell.

Adrenergic beta-Antagonists↗
PubMed2001

Glycaemic control in type 1 diabetic patients using optimised insulin aspart or human insulin in a randomised multinational study.

Insulin aspart (IAsp), is a rapid-acting analogue of human insulin (HI), for use in the meal related treatment of diabetes mellitus. The degree of glycaemic control achieved by IAsp in comparison with HI after algorithm-driven dose optimisation was tested over 3 months. The prospective, multicentre, randomised, open-label study with parallel groups was performed in 48 centres in 11 countries and included 423 basal-bolus treated patients with Type 1 diabetes. Main outcome measures were blood glucose control assessed by HbA1c, nine-point self-monitored blood glucose profiles, insulin dose, quality of life, hypoglycaemia and adverse events. An algorithm-driven increase occurred in the dose and number of daily injections of basal insulin, particularly in the IAsp group. After 12 weeks of treatment, HbA1c was significantly lower in IAsp compared to HI treated subjects by 0.17 (95% CI 0.30-0.04) (P<0.05). Comparison of the blood glucose profiles showed lower blood glucose levels with IAsp after breakfast (mean 8.4 vs 10.1 mmol/l; P<0.0001) and dinner (8.2 vs 9.3 mmol/l; P<0.01). There were no differences between treatments in the incidence of hypoglycaemic episodes or in the adverse event profiles. The WHO Diabetes Treatment Satisfaction Questionnaire score for perceived hyperglycaemia was lower with Iasp (P=0.005), and patients found the insulin aspart treatment more flexible (P=0.022). The current study underlines the need for optimising the basal insulin regimen in order to take full advantage of the pharmacodynamics of IAsp.

Adult↗
PubMed2001

Impact of serum basic fibroblast growth factor on prognosis in human renal cell carcinoma.

Renal cell carcinoma is often characterised by extensive vascularity and angiogenic factors may be of importance for disease progression. Using a sandwich enzyme immunoassay, basic fibroblast growth factor (bFGF) was analysed in the sera from 206 patients with renal cell carcinoma before the initiation of therapy. The median bFGF level was 3.0 pg/ml (range <1.0-70.9 pg/ml). The serum levels were significantly correlated to tumour stage and nuclear grade. Patients with tumour thrombus to the renal or the inferior caval vein had significantly higher serum bFGF levels compared with those with non-invading tumours (P=0.007). Patients with serum bFGF levels above 3.0 pg/ml had a worse prognosis, compared with those with lower levels (P=0.001). Furthermore, patients with tumours with vein invasion had a worse prognosis compared with those without invasion. After multivariate analysis, only tumour stage and grade remained as independent prognostic factors.

Adult↗