Search PubMed⌕ Search

Biomedical subjects

H J Hansen

Publications and source records attributed to H J Hansen.

At least 109 records · Page 6Linked to original sources

Clomipramine and mianserin in chronic idiopathic pain syndrome. A placebo controlled study.

The reduction of pain by two antidepressants, clomipramine and mianserin, was, in this study on 253 patients with chronic idiopathic pain syndrome, found to be not better than a placebo when all patients were compared independently of the classification of pain. The improvement rate was around 40% after 6 weeks of treatment when using a 50% or better reduction in pain level. However, in patients who fulfilled a checklist definition of minor to major depression (30% of the total patient material) clomipramine was superior to mianserin and placebo with an improvement rate of 75% after 6 weeks. Using pain curves over time as outcome measure in the various clinical pain categories it was found that both mianserin and clomipramine seemed superior to placebo in patients with tension headache, but in patients with low back pain syndrome placebo was superior to the two antidepressants. No difference among the three treatments was found in patients with burning mouth syndrome or in patients with abdominal pain. These differences underline the importance of studying specific pain syndromes rather than composite groups of patients with idiopathic pain. The clinical significance of these pain curves needs further placebo controlled investigations.

Adolescent↗

Imaging of colorectal carcinoma with radiolabeled antibodies.

Colorectal cancer has been the tumor type most frequently studied with radiolabeled antibodies. Among the various antibodies, a majority of patients with colorectal cancer have received xenogeneic polyclonal or monoclonal antibodies against carcino-embryonic antigen. This review summarizes the current status of colorectal cancer imaging with radiolabeled antibodies, ie, radioimmunodetection (RAID), and examines the published studies involving carcinoembryonic antigen (CEA) antibodies and 17-1A, 19-9, and B72.3, and other monoclonal antibodies. In order to better address the issue of the current and future clinical usefulness of this emerging technology, particular attention is given to the protocols, methods, and results of the published studies. Despite differences in study parameters, antibodies and forms, labels, administration routes and doses, and scanning instruments and methods, it has been found that (1) almost no adverse reactions have been evident; (2) antibody fragments are preferred over whole immunoglobulin G reagents because they achieve higher tumor-to-background ratios earlier, thus reducing or precluding the need for dual-isotope subtraction methods or long delays before imaging; (3) use of antibody fragments, including the monovalent Fab' form, permits imaging with short-lived radionuclides of excellent photon properties, such as 123I and 99mTc; (4) circulating antigens against which the imaging antibody is directed can complex with the injected antibody, but such complexes have not prevented successful RAID; (5) patients with high serum titers of the appropriate antigen target usually have higher rates of positive RAID; (6) patients who are seronegative for the tumor antigen being studied can have positive RAID findings, which can represent the detection of occult lesions; (7) single photon emission computed tomography appears to provide better image resolution than planar scanning; (8) regardless of the sensitivity reported in any particular study, almost all investigators have observed the disclosure of occult neoplasms by RAID; and (9) RAID, a more functional test of usually high specificity, can complement other radiological methods, such as computed tomography scans, which are limited to structural information.

Antibodies, Monoclonal↗

Silicate pneumoconiosis in camels (Camelus dromedarius L.).

In a random screening of camel diseases in Somalia dust-laden macrophages in lungs and/or bronchial lymph nodes were discovered in 94 of 134 animals. In 44 cases the dust-laden macrophages occurred in a number of small or large aggregates. There was a significant positive correlation between dust-laden macrophage aggregates in the lungs and pulmonary fibrosis not related to other chronic lung diseases, such as echinococcosis and chronic pneumonia. Six cases showed a cellular reaction and hyalinized nodules of the classic silicotic type. Energy dispersive X-ray analysis of the dust particles revealed presence of silica, aluminium, potassium and iron in that order. The possible clinical significance as well as the comparative pathology of the observations is discussed.

Animals↗

Search for a retrovirus in long-term cultured cerebrospinal fluid cells and peripheral blood mononuclear cells from patients with multiple sclerosis.

Long-term peripheral blood mononuclear cell (MNC) cultures stimulated with interleukin 2 (IL-2) or IL-2 + phytohemagglutinin were established from 33 multiple sclerosis (MS) patients, 9 with other neurological diseases (OND), and 24 normal controls (C). Cultures were analysed for growth characteristics, reverse transcriptase (RT) in the culture medium, 2'-5' oligoadenylate synthetase in the cells, and cell morphology. None of these parameters differed in the MS group compared with the OND and C groups. Furthermore, 11 cerebrospinal fluid cell cultures were established without feeder cells. Morphology studies of the cells and RT assays of the supernatants from these cultures were normal. Induction studies by dexamethasone and 2-bromo-5'-deoxyuridine in 2 of these cultures did not reveal any signs of a virus. The significance of these results for the retrovirus hypothesis is discussed.

Adult↗

The phagocytic activity of monocytes and polymorphonuclear leucocytes against viral antigens as measured by chemiluminescence in patients with multiple sclerosis.

Twenty-two patients with Multiple Sclerosis in different stages of the disease were investigated in a chemiluminescence-assay and compared with a similar number of healthy individuals. The reactivity of peripheral blood monocytes to different viral antigens was followed by measurement of both the immediate oxidative activity and the development of activity through a 85-minutes period. The patients with a progressive course of the disease showed a high activity and reached maximum activity in a shorter time than the other groups, indicating an activation of the monocytes in these patients.--The patients in steady state showed a rather low activity, compared with both the other patient groups and the control group. A possible significance of these findings is discussed. The activity of the polymorphonuclear cells did not show differences in activity between the groups.

Adult↗

Solving the problem of antibody interference in commercial "sandwich"-type immunoassays of carcinoembryonic antigen.

We evaluated the effect of human anti-murine antibodies (HAMA) on apparent concentrations of carcinoembryonic antigen (CEA) as measured in serum with commercial enzyme immunoassay (EIA) kits manufactured by Abbot ("two-step" double monoclonal antibody assay), Roche, and Hybritech (room-temperature protocol). In sera from patients given parenteral murine monoclonal antibody for experimental diagnostic and immunotherapy studies, HAMA titers were determined with Immunomedics' "ImmuSTRIP HAMA-EIA" kit reagents. "True" CEA titers were established by using the ImmuCEA/MA-EIA and heat-extraction to destroy HAMA before assay for CEA. The concordance of the ImmuCEA/MA assay with the Abbott and Roche CEA EIAs was established with sera from normal individuals and from patients who had not received parenteral injections of murine monoclonal antibody. At high (100 mg/L) concentrations of HAMA, false-positive results were observed with all three kits. The Hybritech and Roche assays were more sensitive to interference by HAMA than was the Abbott CEA-EIA, false-positive results being observed at HAMA concentrations between 1 and 10 mg/L. Similar sensitivity of the three kits to interference by primate anti-MAb sera was demonstrated. Use of primate anti-MAb sera to create controls with HAMA activity and of analyte is recommended to evaluate MAb assays for potential HAMA interference and for use to devise methods to eliminate HAMA interference.

Animals↗

Murine monoclonal antibody adsorbed onto vinylidene fluoride floccules used to eliminate antibody interference in "sandwich"-type immunoassays.

We have previously reported that human anti-mouse IgG antibody (HAMA) can cause false-positive and false-negative results in "sandwich"-type monoclonal antibody (MAb) assays. To eliminate HAMA interference in "sandwich"-type MAb assays, we investigated the use of MAb on solid-phase, vinylidene fluoride floccules, which we have previously used as a solid-phase second antibody for RIA. The simple procedure effectively removes greater than 95% of HAMA from the most positive serum we have obtained from patients hyperimmunized to murine MAb, and it allows for accurate quantification of carcinoembryonic antigen. The solid-phase complex, added to blood, effectively removes HAMA and (or) "HAMA-type" heterophilic antibody from the sera or plasma.

Adsorption↗

Reduction of radioantibody-induced myelotoxicity in hamsters by recombinant interleukin-1.

Recombinant human interleukin 1 (IL-1) administered i.p. to tumor-bearing hamsters results in a dose-dependent 2- to 5-fold increase in total peripheral white blood cells. These levels remain elevated for 2 to 3 wk and then decline to base-line levels. Pretreatment of animals with similar doses of IL-1 prevents radioimmunotherapy-induced destruction of the radiosensitive hematopoietic system. Furthermore, recovery from radio-immunotherapy-induced myelosuppression is possible if animals are given IL-1 1 wk after radioimmunotherapy treatment. Thus, both protection and rescue from the hematopoietic damage associated with radioantibody treatment are feasible by pre- or posttreatment with IL-1.

Animals↗

Platelet 3H-imipramine binding in psychogenic pain patients.

High-affinity binding of 3H-imipramine was analyzed in platelet membranes from patients with chronic psychogenic pain. The patients who in addition to the pain also showed affective symptoms such as depression and anxiety had lower binding than the pain patients without these symptoms.

Adolescent↗

Quantitative Doppler ultrasound evaluation of occlusive arterial disease in the lower limb.

Forty consecutive patients with lower limb arterial disease were evaluated using a multi-gated pulsed Doppler system. Doppler signals were sampled at 4 sites in each limb, and following spectral analysis, the pulse rise time (PRT) was measured. The value obtained at the location giving the longest duration of PRT was used for comparison with ankle/brachial pressure index (A/B index) and angiography. A highly significant correlation was found between PRT and A/B index (r = -0.75, P less than 0.001). Based on receiver operating characteristic curves an overall diagnostic accuracy of 90% in diagnosing a pressure reduction greater than 20% was obtained. The diagnostic accuracy in detecting an angiographic stenosis greater than 50% was almost identical. Based on combined quantitative and qualitative analysis of Doppler signals sampled at the common femoral and popliteal artery, the aorto-iliac segments and the femoro-popliteal segments were evaluated separately. Comparison with arteriography revealed overall accuracies of 96% in the aorto-iliac segments and 87% in the femoro-popliteal segments. It is concluded that simple quantitatively measurable parameters in the Doppler spectrum may accurately predict and localize hemodynamically significant arterial lesions of the lower extremities.

Adult↗

Pulsed multigated Doppler ultrasonography in the diagnosis of carotid artery disease.

To evaluate the accuracy of a pulsed multigated Doppler system, 128 carotid arteries were examined. The spectral broadening index was calculated from the power spectrum of a small sample volume located in the center of the stream according to the flow profile and was related to the degree of stenosis as determined by contrast angiography. Even minor wall irregularities seen on the angiogram were classified as disease. The ability of the system to discriminate between normal and diseased vessels reached a sensitivity of 94% and a specificity of 91%. Classification of greater than 50% or less than 50% stenosis could be performed with a sensitivity of 90% and a specificity of 85%. Pulsed multigated Doppler ultrasonography allows identification of even minor degrees of stenosis of the carotid artery and provides an alternative to duplex scanning. Furthermore, the blood flow profile provided by a multigated Doppler system may add valuable information concerning blood flow characteristics not obtainable by single-gated systems.

Adult↗

"Sandwich"-type immunoassay of carcinoembryonic antigen in patients receiving murine monoclonal antibodies for diagnosis and therapy.

Measurements of carcinoembryonic antigen (CEA) in blood increased dramatically in some patients who were receiving injections of monoclonal antibody. CEA titers were measured with a monoclonal antibody-based double-determinant enzyme immunoassay in which untreated plasma specimens were diluted with an equal volume of buffer containing mouse serum. Increasing CEA titers were accompanied by the appearance and coincident increase in titers of human antibody against mouse Ig (HAMA). Adsorption of these sera with solid-phase anti-human IgG or Protein A restored antigen titers to pretreatment values; evidently the serum factor eliciting false-positive CEA titers was most probably HAMA. Neither addition of undiluted mouse serum to the assay mixture nor pretreatment by heating plasma specimens to 70 degrees C effectively abolished HAMA interference. By contrast, protein precipitation with polyethylene glycol (130 g/L) or heating plasma samples to 90 degrees C eliminated false-positive titers caused by HAMA, but did not reduce authentic CEA titers.

Animals↗

Evaluation of chimpanzee antiserum to human carcinoembryonic antigen.

An adult chimpanzee (Pan troglodyte) with an endogenous circulating carcinoembryonic antigen (CEA) level of 60 ng/ml was immunized s.c. with human CEA. After 1 year of immunizations, the anti-human CEA antibody titer had plateaued. This chimpanzee antiserum demonstrated high avidity specific recognition of human CEA and showed ionic strength effects for CEA recognition similar to those previously described for goat and baboon anti-CEA antisera. Radioimmunoassay of 93 human plasma samples for CEA content using chimpanzee anti-CEA versus Roche goat anti-CEA antisera gave essentially identical results (R = 0.985). Endogenous CEA in chimpanzee blood was very poorly identified by chimpanzee anti-human CEA antisera compared to Roche goat antisera. Column chromatography of human and chimpanzee CEA in the presence of chimpanzee anti-CEA antibody showed only reactivity for the human CEA. In addition, chimpanzee antiserum had only minimal blocking effect on the binding of either goat or baboon antiserum to human CEA. We conclude from these studies that chimpanzee anti-human CEA antiserum recognized a determinant(s) on human CEA which was different from these recognized by goat or baboon antiserum to human CEA and this determinant(s) was poorly represented on chimpanzee CEA. In contrast, the human CEA determinant(s) recognized by baboon and goat anti-CEA antiserums were readily detected on chimpanzee (CEA).

Animals↗