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Biomedical subjects

F Jensen

Publications and source records attributed to F Jensen.

At least 19 recordsLinked to original sources
PubMed2004

[Clinical relevance of computed tomography under emergency conditions--diagnostic accuracy, therapeutic consequences].

PURPOSE: To evaluate the diagnostic accuracy and therapeutic consequences of computed tomography performed on an emergency basis in a primary care hospital. MATERIAL AND METHODS: In 418 patients, 463 computed tomographies (thorax, abdomen, pelvis, spine, aorta, neck and extremities) were performed with-in 12 months, providing 999 diagnoses. The computed tomography diagnoses were retrospectively evaluated and correlated to surgery and discharge diagnoses. Therapeutical consequences were analyzed and allocated to a time period < 36 h (urgent) and > or = 36 - 72 h (elective). Average age was 49 (1 - 94) years (41% female and 59% male). Discharge diagnosis was defined as gold standard, provided that it was supported by clinical, blood chemical, diagnostic and possible surgical data. RESULTS: In 176 of 999 diagnoses (18%), the diagnoses were classified as "non-correlatable". Of the 823 correlated diagnoses, 431 were true positive, 14 false positive, 66 false negative and 312 true negative. Sensitivity, specificity and diagnostic accuracy of computed tomography was 87, 96 and 90%. Computed tomography had therapeutic consequences (surgery, drainage, puncture, reposition, thrombolytic therapy, chemotherapy, bronchoscopy, endoscopy, percutaneous transluminal angioplasty, coiling etc.) in 57% and no direct therapeutic interventions in 43%. Computed tomography excluded the suspected diagnosis in 36% and resulted in a conservative therapeutic regiment in 7%. Surgery was performed on 134 of the 418 patients (32%) who underwent computed tomography, with the surgery urgent in 71 (17%) and elective in 63 (15%) of the 418 patients. CONCLUSION: The high diagnostic accuracy and consecutive therapeutic consequences of computed tomography in establishing a precise, timely and reproducible diagnosis confirm its important role as primary diagnostic method on an emergency basis.

Adolescent↗
PubMed2004

In-situ bypass surgery on arteriographically invisible vessels detected by Doppler-ultrasound for limb salvage.

AIM: The aim of this paper was to evaluate our primary experience with bypass surgery on arteries only visible on Doppler-ultrasound in patients suffering from critical lower limb ischemia. METHODS: During a study period of 10 months, Doppler-ultrasound routinely supplemented digital subtraction arteriography (DSA) whenever it failed to reveal patent runoff vessels suitable for in-situ saphenous vein bypass surgery. If an arteriographically invisible runoff artery was detected on Doppler-ultrasound and the patient was eligible for surgery, a bypass procedure was performed. All patients were facing a lower limb amputation due to critical limb ischemia (tissue loss, SVS/ISCV-category 5). Postoperatively the patients were followed according to a standard graft surveillance program, including clinical examination, ankle pressure measurements and a color Doppler-ultrasound at discharge and after 1, 6 and 12 months. RESULTS: Fifty-one in-situ saphenous vein bypasses were performed, 5 (10%) on arteriographically occult runoff vessels detected only on Doppler-ultrasound. After a 12-month follow-up, 3 bypasses were still patent and only one patient had an amputation. One bypass occluded after 6 months but the patient stayed asymptomatic. CONCLUSIONS: Doppler-ultrasound permits in-situ by-pass surgery on arteriographically invisible vessels reducing the proportion of inoperable patients by 10%.

Adult↗
PubMed2003

Ultrasound contrast-agent improves imaging of lower limb occlusive disease.

OBJECTIVES: to evaluate if ultrasound contrast-agent infusion could improve duplex-ultrasound imaging of peripheral arterial disease (PAD) and increase the agreement with digital subtraction arteriography (DSA). DESIGN: prospective and consecutive study. MATERIAL: of 60 consecutive PAD patients, 15 were found to have an inconclusive duplex-ultrasound scan of the trifurcation and were included in the study. All 15 patients (53% male) were scheduled for DSA, all being candidates for vascular surgery due to claudication (n = 3, 20%), rest pain (n = 5, 33%) and tissue loss (n = 7, 47%). METHODS: on the day before DSA, a duplex-ultrasound scan of the trifurcation was performed. If the duplex-ultrasound scan was found inconclusive, it was repeated during continuous ultrasound contrast-agent infusion. DSA was performed unaware of the duplex-ultrasound results and served as the gold standard. RESULTS: after contrast-agent administration, the number of inconclusively diagnosed segments was significantly reduced by 26 (70%), from 37 to 11(p < 0.001). In 19 segments (73%) contrast-agent infusion changed the diagnosis in accordance with the DSA (p < 0.05). Values of sensitivity and positive predictive value were improved from 0.20 (0.04-0.62) to 0.47 (0.26-0.69) and 0.50 (0.10-0.91) to 0.80 (0.49-0.93), respectively. Specificity and negative predictive value were unchanged. Agreement between duplex-ultrasound and DSA were improved from poor (kappa = 0.18 (95% CI: 0-0.82)) to moderate (kappa = 0.45 (0.17-0.74)) (p = 0.44). CONCLUSION: ultrasound contrast-agents improve the diagnostic ability of duplex-ultrasound when scanning difficult arterial segments in patients suffering from PAD.

Adult↗
PubMed2001

[TPO immunostaining of the solitary, cold thyroid nodules].

INTRODUCTION: The chance of malignancy in scintigraphically cold thyroid nodules is 2-24%. Differentiation between malignant and benign cytology is difficult. The aim of this study was to evaluate the ability of immunostaining (MoAB47--raised against thyroid peroxidase (TPO)) to differentiate between malignant and benign cells taken from cold thyroid nodules by fine needle aspiration biopsy (FNAB) in order to reduce the number of unnecessary thyroid operations. MATERIALS AND METHODS: One hundred and eighty-one patients (150 female) with a scintigraphically cold, solitary thyroid nodule were entered between 1993 and 1996. Fifty-seven were excluded for various reasons. Material removed by FNAB was stained with MoAB47 and routine staining. Staining of 80% or more of the cells was considered benign, less than 80% was considered malignant. Routine staining of operatively removed material was used as the final diagnosis. RESULTS: A pattern with negative TPO staining was found in all lesions that were subsequently proved to be malignant. In all but one, the lesions subsequently diagnosed as being benign stained positive for TPO. The sensitivity and specificity were respectively 1.0 and 0.99. CONCLUSION: TPO immunostaining of material removed by FNAB is a powerful tool in the differentiation between benign and malignant tumours.

Adolescent↗
PubMed2001

The effects of an HIV-1 immunogen (Remune) on viral load, CD4 cell counts and HIV-specific immunity in a double-blind, randomized, adjuvant-controlled subset study in HIV infected subjects regardless of concomitant antiviral drugs.

OBJECTIVE: We examined the activity of an HIV-1 immunogen (Remune) on viral load, CD4 cells and HIV-1 specific immunity. METHODS: Plasma and peripheral blood mononuclear cells were obtained in a predefined random subset of subjects (n = 252) from a multicentre, double-blind, adjuvant-controlled phase III clinical endpoint study. RESULTS: The subjects treated with the HIV-1 immunogen had a significantly greater decline in viral load at multiple time points (P < 0.05), a trend towards increased CD4+ T cell counts and significantly enhanced HIV-1 specific immune responses as measured by HIV-1 lymphocyte proliferation (P < 0.001) compared to the adjuvant control group. Furthermore, in the HIV-1 immunogen treated group, enhanced HIV-1 specific lymphocyte proliferative immune responses were associated with decreased HIV-1 plasma RNA. CONCLUSION: These results suggest that, in a predefined, random subset of subjects, a beneficial effect of the HIV-1 immunogen was observed on viral load, CD4+ T cells, and HIV-specific immunity. These differences were observed in a background of multiple drug therapies. Ongoing trials are evaluating the effect of the combination of this HIV-1 specific, immune-based therapy with potent antiviral drug therapy on virological outcomes.

AIDS Vaccines↗
PubMed2001

Screening for aortoiliac lesions by visual interpretation of the common femoral Doppler waveform.

OBJECTIVE: to study the accuracy of simple visual interpretation of the common femoral artery Doppler waveform for screening the aorto-iliac segment for significant occlusive disease. DESIGN: prospective and semi-blinded study. Material ninety-four consecutive and elective patients having arteriography due to chronic lower limb ischaemia, presenting symptoms of severe claudication (23%), ischaemic rest pain (34%) or ischaemic skin lesions (43%). METHODS: one day prior to conventional arteriography a Doppler waveform was obtained in the common femoral artery. Based on visual interpretation, the waveforms were immediately categorised as normal or abnormal. Comparison with single plane arteriography with respect to significant aorto-iliac occlusive disease was undertaken. RESULTS: visual Doppler waveform interpretation had a sensitivity of 98% (95% CI: 90-100%), a specificity of 81% (CI: 67-90%), a positive predictive value of 86% (CI: 75-93%) and a negative predictive value of 97% (CI: 86-100%) for prediction of significant aorto-iliac occlusive disease using conventional arteriography as the gold standard. The kappa value for the agreement between Doppler waveform interpretation and arteriography was 0.81 (0.68-0.93), representing very good agreement. CONCLUSION: a normal common femoral Doppler waveform can safely exclude significant upstream aorto-iliac lesions and is a useful timesaving screening tool in the busy vascular laboratory. The method is well tolerated, easy to perform and requires no additional equipment.

Adult↗
PubMed2000

[Thoracic hydatic cysts. An important differential diagnosis to tuberculosis among immigrants].

Hydatid cysts, caused by Echinococcus granulosis, most commonly occur in the liver as a space-occupying lesion; the second most common are lung cysts, whereas rupture into the pleural space occurs very rarely. A case of intra-thoracic hydatid cysts with invasion of the pleural space and rupture into the thoracic muscle is described in a young immigrant from Morocco to Europe (Denmark). Hydatid cyst is an important differential diagnosis from tuberculosis in immigrants from areas with endemic echinococcosis and tuberculosis, such as North Africa and the Middle East.

Adolescent↗
PubMed2000

Pyrrolo-annelated tetrathiafulvalenes: the parent systems

The synthesis of a number pyrrolo-annelated tetrathiafulvalenes, including the parent bis(pyrrolo[3,4-d])tetrathiafulvalene (7) is decribed. Starting from readily available 4,5-bis(bromomethyl)-1, 3-dithiole-2-thione (14) and sodium tosylamide, the parent 7 and the asymmetric monopyrrolo tetrathiafulvalenes 23a,b were prepared in good yields via a nonclassical and simple pyrrole synthesis. Furthermore, a series of asymmetrical N-alkylated monopyrrolo/monodihydropyrrolotetrathiafulvalenes was prepared starting from primary amines and 14. A detailed study of the fundamental redox behavior of this class of heterocycles is reported. NMR spectroscopy, cyclic voltammetry, and PM3 MO calculations revealed that the pyrrolo-annelated tetrathiafulvalenes have highly extended pi-surfaces. The X-ray crystallographic analyses of the monopyrrolo tetrathiafulvalenes 22b and 24b, together with preliminary formation of a charge-transfer complex between the parent donor 7 and TCNQ, are also reported.

Journal Article↗
PubMed2000

In vitro immune function after vaccination with an inactivated, gp120-depleted HIV-1 antigen with immunostimulatory oligodeoxynucleotides.

We examined the effect of a synthetic oligodeoxynucleotide containing unmethylated CpG immunostimulatory sequences (ISS) as an adjuvant for an HIV-1 immunogen (inactivated, gp120-depleted HIV-1 virus particles). The addition of the ISS to HIV-1 in incomplete Freund's adjuvant (IFA) was the optimal combination for the production of HIV-1-specific immune responses as measured by IFN-gamma (p=0.002) and IgG antibody production. Furthermore, the group that was immunized with HIV/IFA/ISS, as well as the group that received HIV-1 in complete Freund's adjuvant (CFA), stimulated significantly more RANTES (a beta-chemokine) (p=0.002) production from lymph node cells. These results suggest that the addition of CpG immunostimulatory sequences to HIV antigens in IFA may optimize HIV-1-specific immune responses and provides further rationale for the testing of ISS in combination with gp120-depleted whole-killed HIV-1 in IFA as a potential preventive or therapeutic HIV-1 vaccine.

AIDS Vaccines↗
PubMed2000

Thyroperoxidase (TPO) immunostaining of the solitary cold thyroid nodule.

OBJECTIVE: To evaluate the value of immunostaining using the monoclonal antibody (MoAB47) against thyroperoxidase (TPO) in distinguishing between benign and malignant tumour cells in fine needle aspiration cytology (FNAC) samples obtained from a solitary cold nodule of the thyroid gland for the purpose of strengthening the indication for thyroid surgery. DESIGN: A prospective, immunocytochemical study of FNACs taken from patients with solitary cold thyroid nodules who presented to Rigshospitalet, Copenhagen, Denmark, during the period April 1993 to May 1996. The first sample series was taken perioperatively in order to test the utility of the method. In the second part of the study samples were obtained preoperatively by ultrasonic guided aspiration. Tissue sections from the nodules obtained during a subsequent operation served as controls. PATIENTS: One hundred and eighty-one patients, 150 women and 31 men, were studied. The age range was 14-89 years with a median age of 44 years. Fifty-seven patients were excluded from the study for various reasons leaving us with a total of 124 nodules from 124 patients for final evaluation. METHODS: FNAC cells and corresponding nodular tissue were stained by immunocyto- and immuno-histochemistry using MoAb47 and by routine staining methods. Samples were considered benign if 80% or more of the epithelial-looking cells of both the FNACs and the histological tissue sections of the nodule were stained by TPO. Consequently, samples were considered malignant if more than 20% of the epithelial-looking cells failed to stain for TPO. Routinely stained tissue cells and sections served as diagnostic controls. RESULTS: A pattern with negative TPO staining was found in all lesions which, by conventional histological staining, were subsequently proven to be malignant. A universal and reliable, positive TPO staining pattern was found in all subsequently proven benign lesions, with the exception of one out of 26 follicular adenomas. This gave the method a sensitivity of 1.0 (negative TPO staining = malignancy in 27 out of 27) and a specificity of 0.99 (positive TPO staining = benign lesion, in 96 out of 97). Positive and negative predictive values were 0.96 and 1.00 respectively. CONCLUSION: Thyroperoxidase immunostaining of fine needle aspirates from solitary, scintigraphically cold nodules of the thyroid gland has proved to be an important and reliable diagnostic tool for distinguishing between benign and malignant nodules. Thus, patients might be spared further surgery if not otherwise indicated.

Adolescent↗
PubMed2000

T-helper-cell proliferative responses to whole-killed human immunodeficiency virus type 1 (HIV-1) and p24 antigens of different clades in HIV-1-infected subjects vaccinated with HIV-1 immunogen (Remune).

The discovery of multiple subtypes of human immunodeficiency virus type 1 (HIV-1) worldwide has created new challenges for the development of both therapeutic and preventive AIDS vaccines. We examined T-helper proliferative responses to HIV-1 clade A, B, C, G, and E whole-killed virus and to HIV-1 clade G and B core (p24) antigens in HIV-1-infected subjects taking potent antiviral drugs who received HIV immunogen (Remune) therapeutic vaccination. Subjects who were immunized mounted strong proliferative responses to both whole virus and core antigens of the different clades. These results suggest that a whole-killed immunogen may have broad applications as a therapeutic as well as a preventive vaccine in the current multiclade HIV-1 pandemic.

AIDS Vaccines↗
PubMed1999

Seroprevalence of human herpesvirus-8 (HHV-8) in countries of Southeast Asia compared to the USA, the Caribbean and Africa.

Seroprevalence of HHV-8 has been studied in Malaysia, India, Sri Lanka, Thailand, Trinidad, Jamaica and the USA, in both healthy individuals and those infected with HIV. Seroprevalence was found to be low in these countries in both the healthy and the HIV-infected populations. This correlates with the fact that hardly any AIDS-related Kaposi's sarcoma has been reported in these countries. In contrast, the African countries of Ghana, Uganda and Zambia showed high seroprevalences in both healthy and HIV-infected populations. This suggests that human herpes virus-8 (HHV-8) may be either a recently introduced virus or one that has extremely low infectivity. Nasopharyngeal and oral carcinoma patients from Malaysia, Hong Kong and Sri Lanka who have very high EBV titres show that only 3/82 (3.7%) have antibody to HHV-8, demonstrating that there is little, if any, cross-reactivity between antibodies to these two gamma viruses.

Adolescent↗
PubMed1999

In vivo development of brain phosphocreatine in normal and creatine-treated rabbit pups.

To study the effects of creatine (Cr) on brain energy metabolism and on hypoxia-induced seizures, 5- to 30-day-old rabbit pups were given subcutaneous Cr (3 g/kg) for 3 days before exposure to 4% O2 for 8 min. In saline-treated controls, hypoxic seizures were most frequent at 15 days (80% of pups) and 20 days (60%) of age. Seizures were prevented at 15 days and reduced 60% at 20 days in Cr-treated pups. In surface coil-localized brain 31P nuclear magnetic resonance spectra, with signal from both cerebral gray (GM) and white (WM) matter, the phosphocreatine (PCr)/nucleoside triphosphate (NTP) ratio doubled between 5 and 30 days of age in controls. In all Cr-injected pups, brain PCr/NTP increased to values seen in 30-day-old controls. When spectra were acquired in predominantly GM and WM slices in vivo, the PCr/NTP ratio was very low in GM at 5 days but reached adult levels by 15 days in controls. In WM, the ratio increased steadily from 5 to 30 days of age. In Cr-injected pups, PCr/NTP increased to mature levels in WM and in GM at all ages. In conclusion, hypoxic seizures occur midway in the time course of brain PCr/NTP increase in rabbit pups as previously described in rat pups. In both altricial pups, systemic Cr increases brain PCr/NTP ratio and prevents hypoxic seizures. These results suggest that mature levels of PCr and/or Cr in brain limit EEG activation either directly or indirectly by preventing hypoxic metabolic changes.

Adenosine Triphosphate↗
PubMed1998

In vivo phosphocreatine and ATP in piglet cerebral gray and white matter during seizures.

The creatine kinase (CK) reaction is thought to be important in coupling ATP metabolism and regulating ADP concentration in tissues with high and variable ATP turnover, including cerebral gray matter (GM). There is low phosphocreatine (PCr), low CK reaction rates, and high mitochondrial CK (MiCK) isoenzyme activity in GM compared to white matter (WM). To compare the CK reaction in GM and WM when ATP metabolism is high, CK reactants and reaction rates were measured in predominantly GM and WM slices in vivo in 2 and 14-day old piglets during pentylenetetrazole (PTZ) seizures using 31P nuclear magnetic resonance (NMR) 1-dimensional chemical shift imaging (CSI). Arterial pressure, temperature, and blood gasses were stable at both ages. Before seizures, the PCr/nucleoside triphosphate (NTP) ratio was higher in WM than GM at both ages with a developmental increase seen in WM. The CK reaction rate constant increased in both regions between 2 and 14 days. During seizures, PCr/NTP increased in GM at 14 days due to increased PCr while the ratio and PCr decreased in WM. The NTP was more stable in WM and GM at both ages. The CK reaction rate decreased in both regions more at 2 than at 14 days. Thus, brain ATP, deduced from NTP, is stable during seizures in the piglet. In GM stable ATP is associated with a unique increase in PCR concentration.

Adenosine Triphosphate↗
PubMed1998

Does Dopplersignal enhancement with Levovist improve the diagnostic confidence of duplex scanning of the iliac arteries?--(A pilot study with correlation to intravascular ultrasound).

OBJECTIVE: To evaluate whether echo-enhancement with Levovist improves the diagnostic confidence of duplex scanning of the iliac arteries. METHODS: Sixteen patients admitted for either PTA (n=7) or femoro-femoral cross-over bypass (n=9) were examined with duplex scanning before and after Levovist injection. The diagnostic confidence was noted before and after the echo-enhancement on a visual analog scale. The following day, intraoperatively, an IVUS examination of the iliac artery was performed. The agreement between duplex scanning before and after enhancement compared to IVUS was evaluated by kappa statistics, and sensitivity-specificity calculations. RESULTS: The diagnostic confidence improved in 50% of the patients, remained unchanged in 44%, and deteriorated in one (6%) patient. The agreement with IVUS was moderate before enhancement (kappa=0.48) and good after the enhancement (kappa=0.63). Sensitivity rose from 64% (before) to 73% (after) Levovist while the specificity was unchanged (100%). These values are not as good as reported by others after fasting of the patients and comparing the results with arteriography. CONCLUSION: Levovist improves the diagnostic confidence of duplex scanning, but marginally. In inconclusive duplex scannings echo-enhancement can supply decisive informations.

Aged↗
PubMed1998

SIVmac vaccine studies using whole inactivated virus antigen sequentially depleted of viral proteins.

Groups of four rhesus monkeys were immunised at 0, 1, 2, and 13 months with whole inactivated SIVmac32H, SIVmac depleted of the outer envelope glycoprotein gp130, virus cores depleted of the lipid membrane (and hence transmembrane glycoproteins), or purified gag protein. These macaques plus controls were challenged with either the homologous SIVmac251-32H grown in human cells or the same virus passed once through monkey cells. None of those challenged with monkey-grown virus were protected, whereas all in the whole and gp130-depleted virus groups, and one in the core group resisted challenge with human-grown virus. As the only difference between the challenge viruses was a single in vitro passage in monkey cells it can be concluded that protection was solely due to human cell components. Finally, passive transfer of high titer IgG from monkeys infected with the homologous challenge virus failed to protect monkeys from infection despite the presence of circulating neutralising antibodies.

Animals↗