1. |
- Babiker-Mohamed, H, et al.
(author)
-
Characterization of monoclonal anti-alpha 1-microglobulin antibodies : binding strength, binding sites, and inhibition of lymphocyte stimulation
- 1991
-
In: Scandinavian Journal of Immunology. - : Wiley. - 1365-3083 .- 0300-9475. ; 34:5, s. 655-666
-
Journal article (peer-reviewed)abstract
- Eleven monoclonal antibodies (MoAb) directed against the immunoregulatory plasma glycoprotein alpha 1-microglobulin were characterized. The MoAb were produced in mice immunized with a mixture of alpha 1-microglobulin homologues from man, guinea pig, rat and rabbit. Using radioimmunoassay, western blotting, affinity chromatography, and Scatchard analysis, the affinities and binding sites of the MoAb were analysed. All antibodies were more or less cross-reactive, but most showed a major specificity for one or two of the alpha 1-microglobulin homologues. None of the antibodies was directed against the carbohydrate moiety of alpha 1-microglobulin. Six of the MoAb had high affinity for the antigen and four of these were directed towards the same part of the molecule though differing in their species specificity. Five showed lower affinity for the antigen and were mainly directed towards epitopes on other parts of the molecule. Only some of the antibodies could block the proliferation of lymphocytes induced by human alpha 1-microglobulin. The blocking efficiency of the different antibodies was similar when tested on the stimulation of human or mouse lymphocytes, suggesting that the same part of the alpha 1-microglobulin molecule is responsible in both species. The magnitude of blocking by the different MoAb was not related to their affinities, emphasizing the importance of where on the alpha 1-microglobulin molecule, rather than how strongly, they bind. The binding of the strongest blocking antibody was shown to be directed to a C-terminal peptide of rat alpha 1-microglobulin, indicating that this part of alpha 1-microglobulin is important for the mitogenic effects. Thus the panel of anti-alpha 1-microglobulin MoAb should be a valuable tool for structural and functional studies of alpha 1-microglobulin.
|
|
2. |
- Borg, A., et al.
(author)
-
Association of int2/hst1 coamplification in primary breast cancer with hormone-dependent phenotype and poor prognosis
- 1991
-
In: British Journal of Cancer. - : Springer Science and Business Media LLC. - 0007-0920 .- 1532-1827. ; 63:1, s. 136-142
-
Journal article (peer-reviewed)abstract
- The human proto-oncogene INT2 (homologous to the mouse INT2 gene, implicated in proviral induced mammary carcinoma) has been mapped to chromosome llql3 and found to share band localisation with, among others, the HST1 proto-oncogene. Both genes are members of the fibroblast growth factor family. In the present study, coamplification (2-15 copies) of the INT2/HST1 genes was found in 27 (9%) of 311 invasive human breast carcinomas using slot blot and Southern blot analyses. Amplification was not correlated to tumour size, axillary lymph node status or stage of disease, neither to patient age nor menopausal status. However, 26 (96%) of the 27 amplified tumours were, often strongly, Oestrogen receptor positive compared to 65% of the unamplified cases (P = 0. 001). These findings are in sharp contrast to the strong correlations of HER-2/neu proto-oncogene amplification with advanced stage and steroid receptor negativity, previously observed in the same series of tumours. Patients with INT2/HSTI amplified breast cancer had a significantly shorter disease-free survival compared to those with unamplified genes (P = 0. 015, median follow up 45 months). This correlation was confined to node-negative patients and persisted in multivariate analysis. No significant correlation to survival from breast cancer was found. It is concluded that amplification of the 1 lql3 region in breast cancer occurs in a particular subset of aggressive tumours, quite different from that identified by HER-2/neu amplification. It still remains to be shown that the selection for amplified genes at llql3 is due to the activity of INT2, HSTl or yet another, still unidentified, neighbouring gene. However, the results are potentially of clinical value in separating a group of node-negative breast cancer for more intense treatment.
|
|
3. |
- Christoffersson, J O, et al.
(author)
-
Nickel-doped agarose gel phantoms in MR imaging
- 1991
-
In: Acta Radiologica. - : SAGE Publications. - 0284-1851 .- 1600-0455. ; 32:5, s. 31-426
-
Journal article (peer-reviewed)abstract
- A method for the production of a tissue-mimicking phantom material for MR imaging is described. The material consists of a nickel-doped agarose gel. The T1 and T2 values of the gel can be varied independently by changing the relative amounts of nickel and agarose. Practically any T1 and T2 combination of clinical interest can be obtained. The long-term stability was studied and found to be good. The relaxation times were estimated using an MR analyzer. The accuracy and the reproducibility of these measurements were evaluated and found to be reassuring. Gel phantoms were also scanned in an MR unit. The signal strength of an inversion recovery sequence was evaluated using the gel phantoms in order to verify their usefulness. These measurements were compared to theory with good agreement. Furthermore, tissue-equivalent phantoms were made. Gels resembling gray matter, white matter, and CSF were scanned. Comparisons with clinical in vivo scans, as well as calculated levels were made. It is anticipated that the gel phantoms described here will be useful in quality assurance as well as in pulse sequence optimization.
|
|
4. |
|
|
5. |
- Ledin, T., et al.
(author)
-
Effects of balance training in elderly evaluated by clinical tests and dynamic posturography
- 1991
-
In: Journal of Vestibular Research-Equilibrium & Orientation. - 0957-4271 .- 1878-6464. ; 1:2, s. 129-138
-
Journal article (peer-reviewed)abstract
- All persons aged 70 through 75 years (N = 457) in a Swedish community were invited to participate in a 9 week balance training study. Out of 55 interested subjects, 15 were chosen at random for a study group; 15 matched controls were also selected. Before and after the investigation period the balance function was assessed by clinical balance tests and dynamic posturography. In the clinical balance tests, the training group significantly improved their balance standing on one leg with eyes closed as well as standing on one leg while shaking the head; they also walked 15 m back and forth faster. In the dynamic posturography the training group significantly improved their equilibrium scores in the 3 most difficult test conditions. The results of the control group were unchanged except for one test condition in the dynamic posturography. The differences in one-leg standing with head shaking, walking 2 x 15 m, and the equilibrium score using sway-referenced platform in dynamic posturography were proved to be attributable to the training. The first investigation in all 29 subjects formed normative dynamic posturography data for the age group 70 through 75 years. The normative posturographic data of this age group differed from previously obtained data in the age groups 20 through 59 and 60 through 69 years. It is concluded that elderly may improve their balance by regular balance training exercises for as short a period as 9 weeks. This might prove to be of great value in improving balance and thereby preventing accidental falls and subsequent fractures in elderly.
|
|
6. |
- Nilsson, Klas, et al.
(author)
-
A novel method of joining thin tubes
- 1991
-
In: EUROJOIN 1. - : Institut de Soudure. ; , s. 253-261
-
Conference paper (peer-reviewed)abstract
- Radiator tubing formed from brass strip, with wall thicknesses from 0.09-0.120 mm (0.0035-0.0047 in.), has been successfully welded at high welding speed using a CO sub 2 laser. A fully penetrated weld was obtained using welding speeds of > 100 m/min (5.47 ft/s) in production like conditions. The laser used for the welding was a 1700 W, Co sub 2 laser with linear polarisation. A tube with a specially designed "Y" joint was formed in a converted lock seam tube machine. There are several advantages to this new type of "Y" joint, such as higher production rate and the possibility of reducing the thickness of the brass strip by 20-30% when compared to material used in high frequency welding. A large number of parameters were studied including the effects of laser power, welding speed, joint geometry and direction of the laser beam polarisation. Two radiators have been made with solder coated, laser welded tubes. These are currently undergoing mechanical testing. Preliminary results of the testing are favourable.
|
|
7. |
|
|
8. |
- Ranstam, J., et al.
(author)
-
Survival in breast cancer and age at start of oral contraceptive usage
- 1991
-
In: Anticancer research. - 0250-7005. ; 11:6, s. 2043-2046
-
Journal article (peer-reviewed)abstract
- In general, findings in studies on oral contraceptives (OCs) and breast cancer have not indicated prognosis to be worse among users of OCs. In few studies, however, has age at the start of OC usage been considered as a prognostic factor. In the present study prognosis in breast cancer is compared with OC usage particularly with age at the start of OC usage among 193 consecutive patients at the Department of Oncology University Hospital Lund. An earlier series of 193 breast cancer patients at Malmo General Hospital is included for comparisons. In the Lund series five-year survival was 62% among women who started to use OCs before the age of 20, 78% among those who started to use OCs between the ages of 20 and 25, and 86% among non-users and those who started to use OCs after the age of 25 (p = 0.009 test for homogeneity). Although age was found to be a prognostic factor in the Lund series (RR = 0.90, p = 0.001) this was not so in the earlier (older) Malmo series. The relationship with age differed significantly between the two series (p = 0.003) suggesting the apparent effect of age at diagnosis to be a cohort effect due to the introduction of OCs during the sixties. The age-specific relationship between survival and OC usage would seem to indicate the presence of a biological mechanism in which OCs may participate during precancerous and early stages of breast cancer.
|
|
9. |
- Rönnqvist, T, et al.
(author)
-
The neutron facility at TSL
- 1991
-
In: Specialists Meeting on Neutron Cross Section Standards for the Energy Region above 20 MeV,Uppsala. ; , s. 103-
-
Conference paper (peer-reviewed)
|
|
10. |
- Sundström, N., et al.
(author)
-
Registration of surface structures using airborne focused ultrasound
- 1991
-
In: Ultrasound in Medicine and Biology. - : Elsevier BV. - 0301-5629 .- 1879-291X. ; 17:5, s. 513-518
-
Journal article (peer-reviewed)abstract
- A low-cost measuring system, based on a personal computer combined with standard equipment for complex measurements and signal processing, has been assembled. Such a system increases the possibilities for small hospitals and clinics to finance advanced measuring equipment. A description of equipment developed for airborne ultrasound together with a personal computer-based system for fast data acquisition and processing is given. Two air-adapted ultrasound transducers with high lateral resolution have been developed. Furthermore, a few results for fast and accurate estimation of signal arrival time are presented. The theoretical estimation models developed are applied to skin surface profile registrations
|
|