PubMed Health⌕ Search

Biomedical subjects

J Ström

Publications and source records attributed to J Ström.

At least 19 recordsLinked to original sources
PubMed2006

High natural aerosol loading over boreal forests.

Aerosols play a key role in the radiation balance of the atmosphere. Here, we present evidence that the European boreal region is a substantial source of both aerosol mass and aerosol number. The investigation supplies a straightforward relation between emissions of monoterpenes and gas-to-particle formation over regions substantially lacking in anthropogenic aerosol sources. Our results show that the forest provides an aerosol population of 1000 to 2000 particles of climatically active sizes per cubic centimeter during the late spring to early fall period. This has important implications for radiation budget estimates and relevancy for the evaluation of feedback loops believed to determine our future climate.

Aerosols↗
PubMed1989

Evaluation of a model for short-term clinical testing of cariogenicity.

Conventional mirror and probe examination and laser fluorescence were used to score caries-like alterations on the buccal surfaces of posterior teeth in 60 panelists, allotted to one of three groups. All subjects refrained from oral hygiene for five days. In one group each subject consumed 12 sucrose candies daily between meals and in the second group each subject similarly consumed 12 palatinose (isomaltulose) candies. The third group served as a control. At the end of the experimental period the tooth surfaces reexamined. Conventional and laser fluorescence scoring techniques showed an increase in the number of caries-like alterations for all groups, but there were no significant differences between the groups. For all groups, the laser method gave significantly greater scores throughout. The findings imply that certain aspects of the early development of enamel caries in subjects regularly using fluorides must be considered in the design of a short-term cariogenicity test. It is concluded that sensitive quantitative methods for the registration of caries are necessary in such tests.

Adolescent↗
PubMed1985

Laser-induced fluorescence from sound and carious tooth substance: spectroscopic studies.

Fluorescence spectra of dentine and enamel illuminated with laser light of wavelengths of 337, 488, 515 and 633 nm respectively were recorded. The fluorescence obtained by illumination with UV laser light at 337 nm had a peak at about 400 nm in dentine as well as enamel. Compared to intact enamel the fluorescence from enamel with initial carious lesions was of lower intensity and had a slight red shift. No fluorescence within the visible range was obtained by illumination with a low power He-Ne laser at 633 nm. Illumination at 488 nm produced fluorescence with a peak at about 540 nm in dentine as well as enamel. The difference in the intensity of fluorescence between sound and carious enamel was generally greater at this wavelength than at any of the others tried, and the red shift from the carious enamel was also more pronounced. Illumination at 515 nm produced fluorescence of similar wavelengths but with much less difference between intact and carious enamel. It was concluded that illumination at 488 nm was the most suitable wavelength of those investigated for the detection of initial carious lesions by the fluorescence technique.

Dental Caries↗
PubMed1979

A study of infections and illnesses in a day nursery based on inclusion-bearing cells in the urine and infectious agent in faeces, urine and nasal secretion.

During an epidemic-free period of nearly 2 years infections and illnesses were followed in a group of small children (2-3 1/2 years) in a day nursery. The incidence of illness was fairly low, 6.3 per child and year. The viral infections were followed by means of the inclusion reaction in the urine and isolation of virus, and the bacterial by culture of nasal secretion. In 60% of the cases the viral infection was accompanied by illness. In 57 cases of illness there were 27 (47%) with merely virus and/or inclusion reaction, 8 (14%) in which bacteria alone were discovered, and 22 (39%) with both. The viral infections were the decisive ones in about 80% of the illnesses. Enteric respiratory viruses of 10 types were detected. 16 (73%) of the 22 children had such an infection on at least one occasion, and spread within the group occurred on infection with echovirus 9, coxsackievirus B4 and reovirus. Enteric viruses accounted for 29% of the viral infections. Streptococci and Mycoplasma pneumoniae played no part in the bacterial infections, which were entirely dominated by pneumococci. Cytomegaloviruria was found in 13 (72%) of 18 children examined. No spread was detected within the group. Rotavirus was on no occasion found in faeces.

Bacterial Infections↗
PubMed1977

Aetiology of febrile mucocutaneous syndromes with special reference to the provocative role of infections and drugs.

The survey covers 266 patients with febrile mucocutaneous syndromes. A brief account of the highly varied clinical picture is given. The syndromes constitute an allergic reaction which in most drug-provoked cases appeared as a late immunological reaction of serum disease type; for the rest sensitization had probably often taken place. An allergic disposition could be traced in 34% of the cases. Infections and drugs were the causative factor 235 cases (88.3%). Infections accounted for 25.2% drugs for 36.1% and both together for 27.1%. An account is given of the provocative bacterial and viral infections and of the role of drugs in cases with and without infection. Among the remaining 31 cases an infection and/or drug may have been the provocative agent in 16 (6 %) whereas 15 (5.6%) may have been due to alimentary and other factors.

Adolescent↗
PubMed1976

Cytological changes in the urine in the form of inclusion-bearing cells, giant cells and haematuria after vaccination with inactivated influenza virus vaccine. A study with application of Millipore procedure and Papanicolaou staining.

Marked cellular reactions in the urine appeared after subcutaneous vaccination with inactivated influenza virus vaccine. Inclusion-bearing epithelial cells increased in 16 cases from 2.4 to 9.6% and erythrocytes from 2.5 to 16.2 per visual field. Pathological values for inclusion-bearing cells were found in 5 of 18 cases (28%), spherical giant cells in 3 (17%), and an abnormal number of erythrocytes in 7 (39%). Killed virus, lacking the capability of replication, thus gave rise both to the formation of inclusions and to fusion of cells within the epithelium of the kidneys and of the urinary tract, and also to haematuria. There was a striking resemblance to the reaction in 34 cases of uncomplicated influenza A2, but the inclusion-provoking effect of the vaccination dose was clearly weaker and the erythrocyturia somewhat less pronounced. As a rule the cellular changes after the vaccination quickly reverted to normal, but there were examples of elevated values still existing after 6 months. Two patients had a high inclusion content and haematuria persisting for 3 and 4 years, one of whom following influenza A2. Influenza and influenza vaccinations may be the cause of certain instances of chronic benign haematuria.

Adult↗
PubMed1975

Cellular elements in the urine in health and in acute infectious diseases, especially with respect to the presence of haematuria. A study with application of millipore procedure and Papanicolaou staining.

The excretion of cellular per litre of urine amounted in healthy persons to, in round figures, one million epithelial cells (2.5 cells per visual field) in both sexes, one million leukocytes in males, one million erythrocytes in females and 0.5 million in males. The maximal excretion was calculated to be 5-6 million per litre. In acute infections the number of epithelial cells and leukocytes in the urine rose to more than the double. Pathological microscopic haematuria, judged by exceeding of the maximal value for normal excretion during the acute phase (24 or more erythrocytes per visual field), occurred in no case of mycoplasma infection, in about 4% of measles, mononucleosis, serous meningitis and hepatitis cases, in about 8% of mumps and streptococcal infections, and in more than 20% of influenza A2 cases. Statistical significance or probable significant existed between influenza and other diseases. The haematuria was unrelated either to the general degenerative or to the specific inclusion-provocative reaction within the renal and urinary tract epithelium. The cause is sought in an involvement of glomeruli with increased diapedesis. The special position of influenza may be explained by the marked haemorrhagic reactions produced by this infection. In one case persistent haematuria combined with increased content of inclusion-bearing cells occurred after influenza. Immunoglobulin deposition in glomerular mesangium may perhaps be one explanation of this haematuria.

Acute Disease↗