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B Forsberg

Publications and source records attributed to B Forsberg.

At least 37 records · Page 2Linked to original sources
PubMed1997

People can detect poor air quality well below guideline concentrations: a prevalence study of annoyance reactions and air pollution from traffic.

OBJECTIVES: Motor vehicle exhaust fumes are the main source of atmospheric pollution in cities in industrialised countries. They cause respiratory disease and annoy people exposed to them. The relation between ambient exposure to air pollution mainly from motor vehicles and annoyance reactions in a general population was assessed. Also, the importance of factors such as age, sex, respiratory disease, access to the use of a car, and smoking habits on the reporting of these reactions was studied. METHODS: A postal questionnaire was sent out in 55 urban areas in Sweden that had nearly identical air quality monitoring stations of the urban air monitoring network. From each area, 150 people aged 16-70 were randomly selected. The questionnaire contained questions on perception of air quality as well as a question on how often exhaust fumes were annoying. RESULTS: Six-monthly nitrogen dioxide concentrations correlated consistently with the prevalence of reported annoyance related to air pollution and traffic exhaust fumes. Black smoke and sulphur dioxide had no significant effects. The frequency of reporting annoyance reactions was higher among people with asthma, women, and people with lack of access to a car. CONCLUSIONS: In this study town dwellers could detect poor air quality at concentrations well below current guidelines for outdoor air pollution. This suggests that questionnaire studies have a place in monitoring air quality.

Adolescent↗
PubMed1996

Measurements of indoor and outdoor nitrogen dioxide concentrations using a diffusive sampler.

The Willems badge, a short-term diffusion sampler, was used to measure nitrogen dioxide concentrations inside and outside the homes of participants in the European study "PEACE' (Pollution Effects on Asthmatic Children in Europe). The main aim of the study was to determine levels of nitrogen dioxide concentrations both outside and inside children's homes, and to estimate the indoor/outdoor ratios for nitrogen dioxide in an urban area, in comparison with a less urbanized control area. We conducted measurements in 23 homes in Umeå, a city of about 100,000 inhabitants in the northern part of Sweden, in addition to 20 homes in a less urbanized control area situated about 20 km from Umeå. Measurements were made on two different occasions in each home during the period January-March, 1994. The houses were not equipped with any gas appliances. The mean outdoor 24-h concentration in Umeå was 28 micrograms m-3 and the mean indoor concentration was 11 micrograms m-3. The mean indoor: outdoor ratio was 0.44 (s = 0.23). The highest outdoor value, measured in the city centre of Umeå, was 54 micrograms m-3. In the control area the mean ambient 24-h concentration was 12 micrograms m-3, approximately half as high as in the urban area, and the mean indoor concentration was 6 micrograms m-3. The mean indoor: outdoor ratio was 0.67 (s = 0.55). The correlation coefficient between indoor and outdoor concentrations was higher in the control area, r = 0.79 (p < 0.001), in comparison with the urban area, r = 0.43 (p < 0.01). It is concluded that the outdoor as well as the indoor concentrations of nitrogen dioxide were approximately twice as high in Umeå as in the control area. This could be explained by heavier traffic density in Umeå. The mean 24-h concentration outside homes in Umeå was, however, below the 24-h national standard level of 75 micrograms m-3. The higher correlation between indoor and outdoor concentrations, combined with higher indoor: outdoor ratio, in the control area is interpreted as a sign of a lower level of penetration of outdoor air into the houses in the urban area. This was not explained by differences in types of buildings between the two areas, but possibly by differences in air-exchange rates and in habits of ventilating rooms with open windows.

Air Pollutants↗
PubMed1996

Genotyping of the platelet-specific alloantigen HPA-5 (Br(a)/Br(b)) using polymerase chain reaction with sequencespecific primers (PCR-SSP).

A DNA-based one-stage technique, polymerase chain reaction with sequence-specific primers (PCR-SSP) was developed for genotyping of the platelet specific alloantigen HPA-5 (Bra/Brb). Sequence-specific primers, matching the wild type and the point mutation responsible for the HPA-5 (Bra/Brb) phenotype, were constructed. Conjointly a fragment of the gene coding for glycoprotein (GP) IIIa was amplified as an internal control of the enzyme reaction. Using these HPA-5 (Bra/Brb) sequence-specific primers the correct fragment of the GPIa gene was amplified, as evidenced by the PCR product size, the restriction map and by the nucleotide sequence. This assay was applied on 187 Swedish blood donors; 157 individuals were found to have a homozygous HPA-5a (Bra/Brb) genotype and 30 individuals a heterozygous HPA-5a,b (Bra/Brb) genotype. None of the donors was found to display a homozygous HPA-5b (Bra/Brb) genotype. Thus, the (HPA-5b) Bra antigen frequency in this population will be approximately 16.0% with a gene frequency of 8.0%. It is concluded that this assay is an attractive technique for genotyping of the HPA-5 (Bra/Brb) alloantigens on genomic DNA. The technique can replace serological alloantigen typing, especially in cases where platelets and rare human alloantisera are not available.

Adult↗
PubMed1995

Cancer risk after renal transplantation in the Nordic countries, 1964-1986.

The theory that cancer may arise under conditions of reduced immune capacity is supported by observations of humans with immune deficiencies such as occur following organ transplants. However, no study on humans has been done in which the reference population was the same as that in which the cancer cases arose and in which there was a sufficiently long period of follow-up. Information on 5,692 Nordic recipients of renal transplants in 1964-1982 was linked with the national cancer registries (1964-1986) and population registries. Person-years at risk were calculated from the date of first transplantation until death or the end of the study period and were multiplied by the appropriate age- and calender-specific incidence rates to obtain the expected numbers of cancers. Standardized incidence ratios (SIR) were calculated after stratification by a number of recorded variables. Altogether, 32,392 person-years were accrued, and 471 cancers occurred, yielding overall SIR of 4.6 (95% CI, 4.0 to 5.2) for males and 4.5 (95% CI, 4.0 to 5.2) for females. Significant overall 2- to 5-fold excess risks in both sexes were seen for cancers of the colon, larynx, lung and bladder, and in men also for cancers of the prostate and testis. Notably high risks, 10-fold to 30-fold above expectation, were associated with cancers of the lip, skin (non-melanoma), kidney and endocrine glands, also with non-Hodgkin's lymphoma, and in women also with cancers of the cervix and vulva-vagina. Among a number of donor and recipient variables studied, including tissue types and compatibility (ABO, HLA, DR), age below 45 years at the time of transplantation was the most important determinant for increased risk at most sites. Kidney transplantation increases the risk of cancer in the short and in the long term, consistent with the theory that an impaired immune system allows carcinogenic factors to act. The tumor risk is small in comparison with the benefits of transplants, but patients should be followed up for signs of cancer.

Adult↗
PubMed1995

The platelet-specific alloantigen PlA1 (HPA-1a): a comparison of flow cytometric immunophenotyping and genotyping using polymerase chain reaction and restriction fragment length polymorphism in a Swedish blood donor population.

BACKGROUND: There is an increasing interest in the development of rapid and reliable techniques for platelet alloantigen typing. STUDY DESIGN AND METHODS: By use of standardized flow cytometry and a specific human alloantiserum, 236 Swedish blood donors were immunophenotyped for the platelet-specific alloantigen, PlA1 (HPA-1a). RESULTS: Ten individuals (4.2%) had low fluorescence intensities and were considered PlA1-negative (HPA-1a-negative); all of them also demonstrated a PlA2/PlA2 (HPA-1b/1b) genotype in a polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) assay of the underlying DNA polymorphism. The remaining population had clear positive fluorescence and was regarded as PlA1-positive (HPA-1a-positive). The fluorescence distribution histogram among PlA1-positive (HPA-1a-positive) individuals was dome-shaped, and those individuals who were homozygous for PlA1 (HPA-1a) could not be distinguished from those who were heterozygous. This finding was further substantiated by PCR-RFLP analysis of the PlA1/PlA2 (HPA-1a/1b) genotype; a heterozygous genotype was found among those having a medium fluorescence intensity as well as among those having a strong fluorescence intensity. CONCLUSION: Flow cytometry is a valuable tool for large-scale detection of PlA1 (HPA-1a). However, flow cytometry based on only one antiserum cannot distinguish between homozygous and heterozygous carriers of PlA1 (HPA-1a). For zygosity testing and when platelets are difficult to obtain, the PCR-RFLP technique is the assay of choice.

Antigens, Human Platelet↗
PubMed1994

Epidemiology of respiratory symptoms, lung function and important determinants. Report from the Obstructive Lung Disease in Northern Sweden Project.

SETTING: Cross-sectional epidemiological study based on a representative sample of the general population in northern Sweden. OBJECTIVES: To assess the prevalence of respiratory symptoms, the role of respiratory symptoms as indicators of impairment of lung function, and to define risk factors for respiratory symptoms and lung function impairment. DESIGN: The 1340 subjects of 6610 who reported respiratory symptoms suggestive of asthma or chronic bronchitis in a postal questionnaire study were invited to a structured interview and lung function tests. A control group of 315 subjects was also invited. Risk factors were assessed from the postal questionnaire. RESULTS: 400 subjects in the symptomatic group had attacks of breathlessness and wheezing, while none in the control group had them, corresponding to 7% of the original study population. Chronic productive cough was present in 537 subjects, of whom 13 were from the control group, suggesting that 12% of the original study population had this symptom. Persistent wheeze was the symptom that predicted the greatest proportion of cases of impaired lung function. Attacks of breathlessness, wheezing, long-standing cough and sputum production were all related to age, smoking and a family history of asthma. Both chronic productive cough and impaired lung function correlated strongly with smoking and age, and their prevalences differed in different socio-economic groups. CONCLUSION: Impaired lung function can be predicted from respiratory symptoms. Data collected in postal questionnaires suffice for the identification of risk factors. Combinations of symptoms gave greater odds ratios than individual symptoms.

Adult↗
PubMed1993

[Evaluation of current rehabilitation activities. Problems and choice of methods].

The evaluation of rehabilitation potential is discussed in the context of the recent allocation by the Riksdag of substantial funds for rehabilitation purposes, a measure designed to generate savings to social insurance at least comparable to the allocation. In the article are discussed the difficulties involved in assessing the impact of such political measures, when at the same time the chances of people being able to return to work after extended sick leave are reduced owing to the recession. An evaluation model is presented which, in addition to variables related to monetary savings to the community, incorporates indicators capable of identifying gains due to a rehabilitation programme that are important determinants of the changes of target groups returning to a productive and meaningful life.

Cost Allocation↗
PubMed1993

Air pollution levels, meteorological conditions and asthma symptoms.

We wanted to assess relations between the daily occurrence of asthma symptoms and fluctuations of air pollution concentrations and meteorological conditions. In a panel of 31 asthmatic patients residing in the town of Piteå in northern Sweden, severe symptoms of shortness of breath, wheeze, cough and phlegm were recorded in an asthma diary together with suspected causes. Sulphur dioxide, nitrogen dioxide, black smoke, relative humidity and temperature were used to evaluate the relationship to the environment. By using multivariate analyses, we found that daily variations in the particulate pollution levels, indicated by black smoke levels below the criteria limits, had significant effects on the risk of developing severe symptoms of shortness of breath. This association was stronger among 10 subjects, who had at least five incident days with severe shortness of breath. Meteorological conditions were not significant in the multivariate models. Cough and phlegm did not show significant relationships to any environmental condition that was evaluated. Only one-third of the subjects reported, at least once during the study, symptoms believed to be related to air pollutants, although we found significant correlations between the pollution levels and the frequency of pollution-related symptoms. We conclude that an association has been established for black smoke as pollutant and shortness of breath as respiratory symptom, and that in certain asthmatics, effects were occurring at lower particulate levels than suggested previously.

Adolescent↗
PubMed1992

Short-term effect of magnesium sulfate infusion on renal function in preeclamptic women.

Magnesium (Mg) plays an important role in cardiovascular homeostasis. A deficiency may be of importance for the etiology of disorders that have vasospasm in common. Mg administration can reduce the peripheral vascular resistance and thus enhance organ perfusion. We observed that Mg sulfate infusion could have a beneficial effect upon the serum urate concentration in preeclamptic women, presumably by affecting the renal function. A study comprising 10 preeclamptic women with a high serum urate level (413-788 umol/l) was carried out. Glomerular filtration rate (GFR) was measured by determination of iohexol clearance. 30 mmol Addex-Magnesium was then given i.v. during 12 h and a second GFR determination performed the next day. We had expected the GFR to increase, but to our surprise, it decreased (in mean, from 74.2 ml/[min x 1.73 m2] to 71.3; p < 0.05; Wilcoxon signed-ranks test). There were no significant changes of blood pressure, proteinuria, blood thrombocytes, transaminases, serum creatinine or serum urate. We conclude that in preeclamptic women with renal dysfunction, Mg infusion therapy had no favourable effect upon either blood pressure nor GFR in the short-term perspective.

Adolescent↗
PubMed1992

[Asthma and allergic diseases in Sweden].

Until recently the prevalence of asthma in Sweden was assessed to be 2-3 per cent. An increase in the prevalence of asthma and allergic rhinitis was noted among new conscripts undergoing health work-ups prior to military service with the most marked increase in northern Sweden, were 5 per cent of conscripts were reported to have asthma. In southern Sweden the prevalence remained about 2 per cent. More recent questionnaire studies in mid- and southern Sweden have reported similar rates of respiratory symptoms and use of anti-asthmatic drugs as in northern Sweden, suggesting that there may be no difference in asthma prevalence between the north and the south of the country. The exact prevalence of allergic diseases among Swedish adults is still not clear, but 40 per cent of adults in northern Sweden report that they often have wheezing in the chest, attacks of breathlessness, longstanding cough or sputum production. In questionnaire studies among children about 40 per cent of respondents have reported that they had asthma, allergic rhinitis or other type of hypersensitivity. The absence of generally accepted diagnostic criteria for asthma and allergic disorders in epidemiological studies makes comparison of prevalence difficult. It is thus not possible to be sure that the prevalence of asthma and allergic disorders in Sweden has recently increased. Risk factors for the development of asthma and allergic disorders are under study in Sweden. Several studies report an association in children between urban living and allergic disorders.

Adolescent↗
PubMed1991

Human leukocyte antigens in relation to colonization by mutans streptococci in the oral cavity.

Mutans streptococci are well established as caries-inducing microorganisms in man. Most humans carry the bacteria, but in highly different numbers. This cannot be explained by environmental factors only. The aim of this study was to investigate a possible association between levels of colonization by mutans streptococci and the presence of certain B and DR human leukocyte antigens (HLA). Altogether, 170 subjects who had their HLA antigens determined (76 renal transplant patients and 94 healthy blood donors) were selected for the investigation. Paraffin-stimulated saliva samples were taken using the wooden spatula method with subsequent cultivation of mutans streptococci on mitis salivarius bacitracin agar plates. An association between the absence of HLA-DR 4 antigens and low, or undetectable, levels of mutans streptococci was found. This was statistically significant for the immunosuppressed renal transplant subjects. The same trend was observed among the healthy blood donors.

Adult↗
PubMed1991

Management of childhood diarrhoea at the household level: a population-based survey in north-east Brazil.

The management of childhood diarrhoea at the household level was studied in a population-based survey in four states in north-east Brazil. Of a representative sample of 6524 children under 5 years of age, 982 (15.1%) had diarrhoea on the day of the interview or had had diarrhoea at some time during the previous 15 days. A total of 66% of the children were not taken for treatment, while government health services were used by 14%, private doctors by 1%, and traditional healers (rezadeiras) by 24%. Oral rehydration therapy was given to 24.3% of the children as follows: solutions of oral rehydration salts (ORS) were received by 6.8%, salt-and-sugar solutions by 14.7%, and solutions of commercial ORS brands by 4.3%. Although 95% of the caretakers knew about rehydration solutions, only 18% prepared them correctly, the most common error being the use of insufficient water. Of the rehydration solutions used, 39% had a sodium concentration that was potentially dangerous (greater than 120 mmol/l), and 8% had a sodium concentration that was very low. Of those solutions prepared using ORS, 38% had too high a sodium concentration, while 14% of the salt-and-sugar solutions prepared using either the "scoop-and-pinch" approach or a plastic spoon were too concentrated. However, potentially the most dangerous were the salt-and-sugar solutions prepared using nonstandard recipes. More than half of these had an unacceptably high sodium concentration or osmolarity.

Brazil↗
PubMed1987

Alpha-adrenergic stimulation and radiosensitivity on the rat submaxillary gland.

The submaxillary glands were exposed to fractionated irradiation comparable to 50 Gy in clinical practice and a single fraction of 50 Gy. Half the number of rats were given cyclocytidine, an alpha-adrenergic agonist which depletes the serous cell granules before irradiation was embarked upon. Our results show that irradiation causes a significant, irreversible destruction of serous cells. With cyclocytidine pretreatment, the radiodamage was diminished and this drug is suggested to act as a radioprotector, depleting secretory heavy metal granules, and thus preventing radiodamage in the submaxillary salivary glands.

Ancitabine↗
PubMed1987

Age at onset, sex distribution and HLA antigen frequency in patients with primary glomerulonephritis progressing to terminal uraemia. An epidemiological survey.

In a retrospective study of 138 HLA-typed patients with primary glomerulonephritis progressing to terminal uraemia, a bimodal curve of age at onset of disease was observed among males. An initial peak occurred between 16 and 25 years of age, and a second peak between the ages of 46 and 55. The prevalence of HLA B40 was found to be high among males in the first group, and a relationship was found to exist between the presence of HLA B40 and increased titres of ASO (antistreptolysin O). No such findings were made either in the second group of males or in the female group. Among females, a single peak for age of onset occurred between 6 and 15 years. The frequency of HLA B40 did not differ significantly from that of the controls. The results of this study suggest a relationship to exist, predominantly in younger males, between primary glomerulonephritis with fatal outcome and HLA B40-related alterations in the immunological response to beta-streptococcal infection.

Adolescent↗