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Biomedical subjects

B Jansson

Publications and source records attributed to B Jansson.

At least 109 records · Page 6Linked to original sources
PubMed1988

HIV transmission by blood transfusions in Stockholm 1979-1985: nearly uniform transmission from infected donors.

Thirty-five out of approximately 800 known HIV-seropositive people in Stockholm by mid-1986 were blood donors during the period 1979-1986. Almost all, i.e. 349 recipients of their blood components (red blood cells, platelets, plasma) could be traced. One hundred and eighty were still alive and 112 of these on further analysis, were suspected of being infected. They were contacted and all but one agreed to be tested for HIV antibodies. Fifty recipients were found to be seropositive. They had been transfused with blood components from 14 of the 35 donors. The earliest observed transmission occurred in June 1982. The patterns of HIV transmission showed, with only one exception, that each donor who had transmitted HIV to one recipient had also transmitted it to all later recipients. Appropriate preserved sera and clinical records from five of the donors who had not transmitted the virus were found and analysed. The result indicated that these donors had acquired their HIV infection after their last blood donation. In conclusion, our study indicates that every antibody-positive donor transmits HIV to almost every recipient.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Alcoholics' beliefs about abuse: causes, effects and treatment.

The beliefs that problem drinkers hold about the causes of abuse, effects of alcohol, and methods of treatment were investigated. The drinkers' beliefs about their own abuse as well as their beliefs about other abusers were both studied. It was found that own abuse was mostly explained by internal factors (drinking to reduce distress or to achieve an elated mood) while external factors (e.g. unemployment) were more often referred to as explanations of the abuse by other persons. Alcohol abuse as an illness was a frequently endorsed concept, while explanations in terms of social or macro level factors were rarely accepted. Females tended to accept more explanations of abuse than males. Many of the problem drinkers tended to see very few explanations for their own abuse and to be quite skeptical about treatment. Factor analysis resulted in three factors: acceptance of reasons for abuse, perceived dependence and experienced control of drinking. Cluster analysis indicated that about 25% of the problem drinkers had a high level of acceptance, perceived dependence and control. These problem drinkers may be a prime target group for treatment.

Adult↗
PubMed1987

A gene fusion system for generating antibodies against short peptides.

A novel method to obtain specific antibodies against short peptides is described, involving synthesis of the corresponding oligodeoxynucleotides followed by cloning into a new set of fusion vectors, pEZZ8 and pEZZ18, based on two synthetic IgG-binding domains (ZZ) of Staphylococcus aureus protein A. The soluble gene fusion product thus obtained, can be collected from the culture medium of Escherichia coli and rapidly recovered in a one-step procedure by IgG affinity chromatography. The system was used to express a fusion protein consisting of the two Z fragments and the C-terminal part [amino acids (aa) 57-70] of human insulin-like growth factor I (IGF-I). This 16-kDa protein was purified by affinity chromatography on IgG Sepharose and antibodies were raised in rabbits. The fusion protein elicited peptide-specific antibodies, as measured by solid-phase radioimmuno assay and Western blotting, reactive with both synthetic C-terminal peptide and the native human IGF-I protein. The results suggests that the gene fusion system can be used for efficient antibody production against short peptides encoded by synthetic oligodeoxynucleotides.

Amino Acid Sequence↗
PubMed1987

Mass spectrometric determination of tris(1,3-dichloro-2-propyl)-phosphate (TDCP) using NCI-technique.

A number of different products suspected to contain flame retardants were analysed. TDCP was found in 11 out of 104 samples. It was most common in polyurethane products such as sound absorbing materials and liners for cars and buses. To get an integrated picture of TDCP exposure the contents of vacuum cleaner bags from two homes were analysed. One of these contained TDCP. To investigate possible presence in humans, blood samples were analysed. For clean-up, Sep-Pak cartridges with C18 phase were used. These cartridges contained TDCP and it was not possible to eliminate this background entirely. The NCIMS detection sensitivity for TDCP was better when analysing plasma extracts than when analysing pure standard solutions. Thus quantitative determinations of TDCP must be made by standard additions to plasma extracts. Something in the blood plasma seems to be able to bind or immobilise a certain amount of TDCP. Therefore it was not possible to analyse amounts less than 600 pg/ml whole blood with this method. None of the 37 analysed blood samples exceeded this value.

Electrochemistry↗
PubMed1987

An ultrastructural and functional study of the inner ear after administration of hyaluronan into the middle ear of the guinea pig.

A single dose of hyaluronan, 19 mg/ml was administered into the right middle ear cavity of guinea pigs. The auditory function of the right ear was tested by recording the gross neural action potential (N1) before, directly after, and 28 days after the administration of hyaluronan. In a control group the right ear was sham-operated and the gross neural action potential (N1) was recorded twice; on the day of the sham operation and 28 days later. All animals were killed 28 days after the operation. All treated as well as sham-operated ears and every second intact ear were studied by scanning electron microscopy (SEM.) No ear had signs of hearing deterioration. Macroscopically, most of the hyaluronan was eliminated from the middle ear after 28 days. In the histological examination, pathological stereocilia were found in the apical turn of the cochlea in the ears to which hyaluronan was administered, the sham operated and the intact ears.

Animals↗
PubMed1986

Magnetic carbohydrate nanoparticles for affinity cell separation.

Magnetically responsive nanoparticles were prepared from enzymatically hydrolysed starch and magnetite. Two different monoclonal antibodies were covalently coupled to the particles. The antibody-coupled particles were in the size range of 100-300 nm and had an iron content of about 60%. Using 100 micrograms of magnetic particles (coupled with monoclonal mouse anti-rat Ig kappa light chain antibody) a very high depletion of surface Ig positive cells (mostly B-cells) from one million rat peripheral blood mononuclear cells could be achieved. The separation efficiency was evaluated by flow cytofluorometric analysis. This technique permits the detection of a small number of surface Ig positive cells among 10,000 negative cells.

Cell Separation↗
PubMed1986

Mathematical model for human myeloma relating growth kinetics and drug resistance.

We present a computer-based mathematical model that can simulate characteristic features of the clinical time course of human myeloma. It asserts that therapy resistance in myeloma cells is an inherited trait associated with the longer inter-mitotic times of some cells and that the strength of this trait affects tumour growth characteristics. These kinetic differences within the malignant cell clone may also influence therapeutic efficacy. In the model, the same total therapy, administered in different time-dose fractions, could be 'curative' or 'minimally effective' depending on kinetic properties. For example, as others have shown, in myeloma pulsed intermittent therapy is often more effective than low dose continuous therapy. According to our model this finding is compatible with a high coefficient of inheritability of resistance from one cell generation to the next. The model also suggests that if there are subclones of varying resistance, a therapy must have some effect on each of them if it is to be employed in a curative fashion. While many aspects of the model are not yet clinically testable, exploration of its concepts might increase knowledge about fundamental neoplastic mechanisms.

Antineoplastic Agents↗
PubMed1986

Evidence for the existence of W3/13+ monocytes in the rat.

Rat blood mononuclear cells were studied with W3/13, OX19, and W3/25 monoclonal antibodies in a dual staining procedure. Cells recognized as W3/13+ OX19- W3/25+ showed a high light scatter pattern were plastic adherent and exhibited spreading, and were identified as monocytes when stained with May-Grunwald-Giemsa. This evidence suggests that at least a subpopulation of monocytes/macrophages are W3/13+.

Animals↗
PubMed1986

One year's incidence of school accidents and their severity in a Swedish municipality.

The aim of this one-year investigation of school accidents was to determine the incidence and severity and to calculate the proportion of school accident cases in relation to all accident cases and to estimate their medical care consumption. All patients were interviewed. The degree of severity was evaluated according to the Abbreviated Injury Scale (AIS). Case-histories and X-ray reports were examined. School accidents constituted five per cent of all accidents in the whole population (including grown ups). In the age group 7-19 years 30% of all accidents were school accidents. One fourth was relatively severe. Our estimations assume that school accidents constitute 5-10% of the total consumption of medical care in the age group. In conclusion, school accidents constitute an important group with regard to incidence and severity. Preventive measures should be targeted towards activities during sports hours and breaks.

Accidents↗
PubMed1986

Geographic cancer risk and intracellular potassium/sodium ratios.

Geopathological, dietary, gerontological, and geophysiological data, data on electrolyte concentrations in healthy cells and in the corresponding tumor cells, and data on the potassium status of patients with different diseases and the associations of these diseases with cancer revealed a common denominator in the potassium-sodium-cancer relationship. A number of independent studies showed that the concentration of intracellular potassium was negatively correlated to cancer rates, whereas the concentration of intracellular sodium was positively correlated to cancer rates. The ratio between the concentrations of intracellular potassium and sodium was negatively correlated to cancer rates and was of greater importance in this respect than the two elements individually. The relations between these concentrations and cancer rates are hyperbolic rather than linear, which explains the fact that two independent carcinogenic agents are synergistic rather than additive.

Age Factors↗
PubMed1985

Low cancer rates among patients with Parkinson's disease.

Among 406 patients with Parkinson's disease, the cancer rate (all sites combined) was bout one-third that for the general population. The risk of cancer increased during the treatment period but remained significantly low. Malignant and benign thyroid neoplasms were significantly more frequent than expected among patients with Parkinson's disease. We suggest that high levels of total body potassium in patients with Parkinson's disease is the protective factor against cancer.

Age Factors↗
PubMed1985

Placebo-controlled study of mesulergine in Parkinson's disease.

We used a new D2 dopamine agonist, mesulergine (8-alpha-amino-ergoline, CU 32-085), to treat 20 patients (12 men and 8 women), mean age 62.6 (SEM = 1.7) and mean duration of illness 5.9 (SEM = 1.0) years. Wearing-off effect was the principal indication for new therapy in 15 patients, and the others had inadequate response to levodopa. All continued on levodopa therapy, and 10 patients were studied in a double-blind controlled test. The mean motor disability decreased from 2.8 (SEM = 0.12) to 1.6 (SEM = 0.18) with mesulergine (p less than 0.0001) and increased to 1.9 (SEM = 0.20) with placebo (p less than 0.001). Tremor improved most, followed by rigidity, bradykinesia, gait, and postural instability. Side effects included dyskinesia, light-headedness, hallucinations, nausea, vomiting, drowsiness, and ankle edema, but, in general, mesulergine was tolerated well.

Aged↗
PubMed1985

Geographic mappings of colorectal cancer rates: a retrospect of studies, 1974-1984.

Geographic mapping of colorectal cancer rates revealed areas with high rates as well as areas with low rates. Comparisons between high-rate areas and areas deficient in selenium led to animal experiments that showed that selenium could reduce chemically induced intestinal tumors. A low-rate area was found to be geochemically unique with soil and water rich in potassium. This led to a series of studies indicating that elevated intracellular potassium reduces cancer risks, while elevated intracellular sodium increases the risks. Variance-reducing techniques and methods for statistical evaluation of clusters were obtained as spinoff results.

Colonic Neoplasms↗
PubMed1984

Mucus transport and surface damage after endotracheal intubation and tracheostomy. An experimental study in pigs.

The effects on mucus transport of different grades of tracheal injury produced experimentally by an intubation tube were studied in 26 pigs. Two of them were not intubated and served as controls, while the rest were anaesthetized and either intubated or tracheostomized, or both, and ventilated for approximately 4.5 h. They were then killed and the trachea and larynx were immediately removed and placed in a specially designed chamber at 37 degrees C and 85% relative humidity. Cardio-green dye was deposited caudally in the trachea as a mucus marker. The mucus transport was observed macroscopically and the ultrastructure of the tracheal wall at the region of mucus arrest was studied by light microscopy and scanning and transmission electron microscopy. In non-intubated pigs the mucus was transported to the posterior larynx. The ciliated epithelium was usually intact along the pathway where cardio-green-stained mucus had travelled. In pigs which had been intubated and/or tracheostomized, mucus transport stopped completely at different levels of the trachea. The damage to the ciliated epithelium varied; in some animals there was almost none at all and in others there was a patchy loss of a large proportion of the cilia, or complete lack of cilia. Lesions which also included epithelial cells were often seen. Tracheal injury due either to a cuffed endotracheal tube or to a tracheostomy tube, with destruction of epithelium and cilia, causes a barrier to mucus transport, leading to arrest and accumulation of mucus further down in the airway. We were unable, however, to demonstrate a direct correlation between grade of damage and tendency to mucus arrest.

Animals↗
PubMed1984

Cellular discriminants for a biological classification of human colon carcinoma.

We categorized established human colon carcinoma cell lines into three biological groups. Our studies were performed on six colorectal cancer lines representing the proposed three groups. Group I consisted of two lines designated LoVo and SW 48; Group II comprised two lines called SW 480 and SW 620; and Group III was represented by lines SW 403 and SW 1116. Group I consisted of the most differentiated cells. This differentiation encompassed morphological markers, gland and signet ring formation, and ciliary development. The outstanding morphological characteristic of Group III was the development of numerous multinucleated giant cells. The range and modal chromosome number increased from Group I to Group III, a change reflected by the higher DNA content of these cells as measured by flow cytometry. Carcinoembryonic antigen synthesis was maximal for Group III and virtually absent for Group II. The number of clonogenic cells decreased from Group I to Group III, while the proportion of nonproliferating cells calculated both by experiments using continuous labeling with tritiated thymidine, and by the primer-available alpha-DNA polymerase index, increased from Group I through Group III. Another important cytokinetic difference was that Group I had an exponential cell cycle stage distribution not seen for the other groups. Cells in Group I were easily propagated in athymic (nude) rats by s.c. injection; cells in Group II injected s.c. grew for about 30 days and then regressed spontaneously. Cells in Group III could only be grown when inoculated intracerebrally. Thus, our studies have now confirmed and extended the hypothesis that cultured human colorectal carcinomas can be separated into at least three groups on the basis of morphological differentiation, chromatin distribution, carcinoembryonic antigen production, cytokinetic properties, and xenograft propagation. Perhaps this classification is just the tip of the iceberg, and future studies will determine the existence of additional groups or subgroups on the basis of other markers. However, at present it appears established that malignant cells with a common histological origin in the gut express their phenotypic potential in a sufficiently discrete manner as to permit their classification into distinct biological groups. Thus, the stage is set for extrapolating this in vitro classification for an in vivo segregation of human colorectal tumors into categories with specific properties and diverse prognosis.

Animals↗