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S Wall

Publications and source records attributed to S Wall.

At least 73 records · Page 4Linked to original sources
PubMed1997

Communicating with the people about HIV infection risk as a basis for planning interventions: lessons from the Kagera Region of Tanzania.

In order to deepen the understanding of risk factors associated with HIV infection in the Kagera region of Tanzania and to investigate the potentials of communicating with the people in planning for interventions, two studies were performed in the districts of Bukoba Urban, Bukoba Rural and Muleba in 1989. The HIV prevalence of these areas ranged between 4.5% and 24.2% according to the prevalence study performed earlier in 1987. The studies involved the community in ward meetings on the one hand, and previously studied individuals on the other hand. The studies aimed both at conveying to the people the results of a previously performed study and at collecting new data using a combination of quantitative and qualitative methods in order to better understand the associated risk factors, perceived or real, and what suggestions the community could offer for reducing HIV transmission in the region. From the initial study, awareness about AIDS was found to be universal. Change of sexual partners and infection with syphilis were found to be the major risk factors for HIV-I infection. From the ward meetings people suggested a variety of solutions for interventions which we have categorized as either "hard" or "soft". The "hard" solutions involved suggestions such as isolation, imprisonment, castration and killing of AIDS victims, while the "soft" solutions involved sympathetic handling of the sick and educating the people about the modes of transmission and how best to prevent infection. There was a greater tendency for the low HIV prevalence rural communities to suggest the "hard" solutions than the high HIV prevalence urban ones which tended to suggest the "soft" solutions. However, with the changing dynamics of HIV infection in the region towards higher HIV prevalence in rural areas, it is likely that the "soft" solutions will gain acceptance and become adopted for interventions throughout the region. The information obtained from these studies has provided lessons that can be used for rational counselling as well as for guiding the implementation of IEC activities geared at interventions. It is also suggested that there should be further research into new strategies or their combinations which could be crucial in prevention such as those of community participation, empowerment of women and solidarity in AIDS intervention work.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Conservation of IS6110 sequence in strains of Mycobacterium tuberculosis with single and multiple copies.

The insertion sequence IS6110/IS986 is used extensively for detecting and typing Mycobacterium tuberculosis. In order to appreciate the evolutionary and epidemiological significance of differences in the fingerprint pattern, it is necessary to understand the factors influencing transposition frequency. Although most strains have many copies of this element, some have only one or two copies; it has been suggested that this apparent transpositional defect arises from the minor differences in the sequence of the element from different strains. In contrast, we have found that the sequence is identical in high and low copy number strains, indicating that external factors, such as the presence of adjacent promoters, must be responsible for differences in copy number.

Base Sequence↗
PubMed1997

Merkel cell carcinoma arising after therapeutic immunosuppression.

Azathioprine and cyclosporin have been used as immunosuppressants for many years, but long-term use has also been associated with neoplasia. We report three cases of rapidly fatal Merkel cell carcinoma in patients who had been treated with azathioprine for many years either for rheumatoid arthritis or following organ transplantation. Two of these patients had also received cyclosporin. We suggest that Merkel cell carcinoma may be seen more commonly in immunosuppressed patients than in the normal population and that the oncogenic potential of azathioprine and cyclosporin should be borne in mind when prescribing these drugs.

Aged↗
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↗
PubMed1997

Adaptation to low-K+ media increases H(+)-K(+)-ATPase but not H(+)-ATPase-mediated pHi recovery in OMCD1 cells.

Studies in rat and rabbit outer medullary collecting duct of inner stripe origin (OMCDis) suggest that both H(+)-ATPase and H(+)-K(+)-ATPase participate in H+ secretion. However, the relative contributions of these transporters, and, in particular, that of H(+)-K(+)-ATPase to K+ absorption have not been defined precisely. The present study was designed to delineate more clearly the response of these two transporters to hypokalemia and acidosis in a newly developed mouse OMCD1 cell line. In cells grown in normal K+ (5 mM) media, intracellular pH (pHi) recovery was similar either in the presence or absence of K+ in the perfusate (delta pHi/min = 0.014 +/- 0.001 vs. 0.017 +/- 0.003, not significant). The inhibitory effects of Sch-28080 (10 microM) and bafilomycin A1 (10 nM) on pHi recovery were evident only in the presence and absence of K+ in the perfusate, respectively. In cells grown in low-K+ (2.5 mM) media to simulate chronic hypokalemia, pHi recovery was significantly faster than in cells grown in normal K+ media (delta pHi/min = 0.045 +/- 0.01 vs. 0.014 +/- 0.001, P < 0.01) and was inhibited specifically by Sch-28080, not by bafilomycin A1. In contrast, in cells preconditioned to low pH (7.0) to simulate chronic acidosis, the enhanced pHi recovery was abolished by bafilomycin A1 but not by Sch-28080. 86Rb+ uptake, when used as a K+ congener, was inhibited by Sch-28080. The K(m) for 86Rb+ uptake (H(+)-K(+)-ATPase activity) and the 50% inhibitory concentration for Sch-28080 were 270 and 5.0 microM, respectively. These studies provide evidence that, in morphologically homogeneous OMCD1 cells, 1) both H(+)-K(+)-ATPase and H(+)-ATPase participate in pHi regulation, 2) the H(+)-K(+)-ATPase is selectively upregulated by preconditioning in low-K+ media, and 3) conversely, preconditioning in low-pH media stimulates only the H(+)-ATPase. Thus, in OMCDis, the H(+)-K(+)-ATPase and H(+)-ATPase respond selectively and independently to chronic hypokalemia and acidosis, respectively.

Adaptation, Physiological↗
PubMed1997

Which babies die during the first week? A case control study in a Nicaraguan hospital.

In a hospital-based case control study (108 and 285 infants) on risk factors for early neonatal death in Nicaragua, an analysis was performed on the possible association with characteristics of the mother and her environment, her reproductive history and contact with antenatal services as well as characteristics of the child. Antenatal medical supervision was associated with a lower risk for neonatal death, even when adjusting for parents' literacy. This association disappeared if birth weight or gestational age was entered into the analysis. There was an interaction between mortality and the mother's versus the father's literacy, showing the highest risk if the mother was illiterate and the father was literate (odds ratio, OR 7.0, CI 2.6-19.3), while illiteracy of both parents was associated to a lower risk (OR 4.2, CI 1.0-18.3). The strong association between maternal literacy and early neonatal death is striking. Is maternal empowerment the important factor?

Asphyxia Neonatorum↗
PubMed1997

Cumulative lead exposure in relation to mortality and lung cancer morbidity in a cohort of primary smelter workers.

OBJECTIVES: The purpose of this study was to determine the mortality and cancer incidence of long-term lead smelter workers at a primary smelter. METHODS: A cohort of 3979 workers employed for at least 1 year during 1928-1979 and a subcohort of 1992 workers employed in lead-exposed departments (lead only workers) was formed. The expected mortality in 1955-1987 and cancer incidence in 1958-1987 were calculated relative to the county rates, specified for cause, gender, 5-year age groups, and calendar year. A cumulative blood-lead index was used for the dose-response analyses. RESULTS: The lung cancer incidence of the total cohort [standardized incidence ratio (SIR) 2.8, 95% confidence interval (95% CI) 2.1-3.8] and the group with the highest exposure (SIR 3.1, 95% CI 2.0-4.6) was high. Similar risk estimates were observed with a latency of 15 years. The workers hired before 1950 had higher lung cancer risk estimates (SIR 3.6, 95% CI 2.6-5.0) than the workers hired later (SIR 1.3, 95% CI 0.6-2.6, no latency period). The risk estimates for lung cancer were further elevated in the subcohort of lead-only workers (SIR 5.1, 95% CI 2.0-10.5 in the highest exposed subgroup; latency period of 15 years). No excesses of other malignancies were noted. CONCLUSIONS: The increased relative risks were probably mainly due to interactions between lead and other carcinogenic exposures, including arsenic. Further study is required concerning such possible interactions before a role in the induction of lung cancer can be ascribed to lead.

Aged↗
PubMed1996

Ion coupling stoichiometry for the norepinephrine transporter in membrane vesicles from stably transfected cells.

We prepared membrane vesicles from stable LLC-PK1 cells expressing serotonin (5-HT) gamma-aminobutyric acid (GABA) and norepinephrine (NE) transporters (SERT, GAT-1, and NET). These vesicles accumulate transport substrates when the appropriate transmembrane ion gradients are imposed. For NET, accumulation of [3H]dopamine (DA) was stimulated by imposition of Na+ and Cl- gradients (out > in) and of a K+ gradient (in > out). The presence of Na+ or Cl-, even in the absence of a gradient, stimulated DA accumulation by NET, but K+ had little or no effect in the absence of a K+ gradient. Stimulation by a K+ gradient was markedly enhanced by increasing the K+ permeability with valinomycin, suggesting that net positive charge is transported together with DA. Cationic DA is likely to be the major substrate for NET, since varying pH did not affect Km. We estimated the Na+:DA stoichiometry by measuring the effect of the transmembrane Na+ gradient on peak DA accumulation. The results suggest a 1:1 cotransport of Na+ with DA. Taken together, the results suggest that NET catalyzes cotransport of one cationic substrate molecule with one Na+ ion, and one Cl- ion, and that K+ does not participate directly in the transport process.

Animals↗
PubMed1996

Diabetes mellitus and health service utilization: a case-control study of outpatient visits 8 years after diagnosis.

All incident cases of diabetes mellitus in the age group 15 to 34 years have been prospectively registered in Sweden since January 1983. To analyse the utilization of outpatient services 8 years after disease onset, we selected the cases registered in 1983 and two controls per case from the general population, matched by age, gender, and county of residence. In 1991, retrospective data about utilization patterns during a 3-month period were collected via a mailed questionnaire, returned by 317 (72%) patients with diabetes and 586 (68%) controls. Seventy-four percent of the cases and 19% of the controls reported at least one visit to a hospital outpatient clinic, including accident and emergency departments. The odds ratio for one visit was 14 (95% CI 9.6-20), for two visits 11 (95% CI 7.0-18), and for three or more visits 8.9 (95% CI 5.6-14). Even when specialized diabetes clinics were excluded from the analysis, the cases had higher odds for visits to internal medicine clinics, to ophthalmology clinics, and to gynaecology clinics, but not for visits to surgical clinics or to accident and emergency departments. Of non-hospital outpatient services, only visits to nurse practitioners were reported by a higher percentage of diabetic responders. Twenty-seven percent of patients with diabetes, as compared to 9% of the controls, had visited both hospital and non-hospital outpatient offices. Females were overrepresented among diabetic high-consumers. The results indicate that most young to middle-aged Swedish persons with diabetes are monitored at hospital outpatient offices, but considerable overlap exists between hospital and non-hospital outpatient services. Further research is needed into the determinants of utilization patterns in diabetes, such as gender.

Adolescent↗
PubMed1996

A one-year community study of under-fives in rural Ethiopia: health and behavioural determinants of morbidity.

Based on a one-year weekly home surveillance study, morbidity patterns of 1,304 children under five years of age in a rural Ethiopian community were measured, together with nutritional and health behavioural determinants. Using Poisson regression models, the study showed that nutritional and health care factors make a significant impact on under-five morbidity. Gastroenteritis was particularly associated with child care factors, while acute respiratory infections were particularly associated with nutritional factors. Lack of immunization, low birthweight and pre-term delivery (more than one month early) were not found to have any independent effect on morbidity. Breast feeding was universal, but the introduction of supplementary foods was found to protect from excess morbidity. The study concludes by discussing possible applications of the results in intervention programmes.

Age Distribution↗
PubMed1996

The childbirth experience: a study of 295 new mothers.

BACKGROUND: The childbirth experience is multidimensional, and therefore difficult to describe and explain. Studies of it have produced inconsistent findings, and the phenomenon is often confused with satisfaction with the care provided. This study aimed to clarify different aspects of the birth experience, and to identify factors that could explain the variation in women's overall assessment of it. METHODS: All Swedish-speaking women in a large city who gave birth during a two-week period in 1994 were given a questionnaire one day after the birth, and 295 (91%) of the questionnaires were returned. Information about the labor process and medical interventions was collected from hospital records. RESULTS: Women usually experienced severe pain and various degrees of anxiety, and most were seized with panic for a short time or some part of their labor. Despite these negative feelings, most women felt greatly involved in the birth process, were satisfied with their own achievement, and thought they had coped better than expected. The overall experience was assessed as positive by 77 percent of women and negative by 10 percent. No statistical difference was observed between primiparas and multiparas in total birth experience, and few differences in the specific aspects of the birth. Of the 38 variables tested in regression analysis, the six that contributed to explaining women's overall birth experience were support from the midwife (sensitivity to needs), duration of labor, pain, expectations of the birth, involvement and participation in the birth process, and surgical procedures (emergency cesarean section, vacuum extraction, forceps, episiotomy). CONCLUSIONS: The study showed that negative and positive feelings can coexist, thus confirming the multidimensional character of the birth experience. Women's assessment of their childbirth is influenced by both physical and psychosocial factors, highlighting the importance of a comprehensive approach to care in labor.

Adult↗
PubMed1996

Heminested inverse PCR for IS6110 fingerprinting of Mycobacterium tuberculosis strains.

A heminested inverse PCR (HIP) for the amplification of sequences flanking the Mycobacterium tuberculosis insertion sequence IS6110 has been developed. The method depends upon primers that anneal to IS6110 at sites between its 5' end and the closest BsrFI site. The accuracy of HIP was demonstrated by the amplification of sequences within plasmid constructs carrying one or two copies of the insertion sequence IS986 in different orientations. The identities of the amplicons produced from strains carrying a single copy of IS6110 were verified by nucleotide sequencing. Analyses of 204 M. tuberculosis strains including those involved in outbreaks showed that IS6110 HIP is highly discriminatory and reproducible. HIP fingerprinting of these 204 strains generated 136 distinct types, and its discriminatory power was equivalent to that of standard restriction fragment length polymorphism analysis. The method is therefore of value for the rapid fingerprinting of M. tuberculosis strains for epidemiological purposes.

Base Sequence↗
PubMed1996

An overview of the Swedish randomised mammography trials: total mortality pattern and the representivity of the study cohorts.

OBJECTIVES: To analyse the cause of death pattern in the cohorts of women included in the Swedish randomised mammography screening trials by comparing the groups of invited and control women both with each other and with the general population of Swedish women. SETTING: Since 1977 four randomised trials of mammography screening have been performed in Sweden: Malmö, Kopparberg and Ostergötland (the two county trial), Stockholm, and Gothenburg. DESIGN: Overview of four randomised mammography screening trials. RESULTS: The total numbers of deaths in the invited and control groups respectively were 15 695 and 11 887 corresponding to a relative risk (RR) of 1.00. There were no significant differences between the invited and control groups for cause-specific mortality, except for breast cancer. When the total mortality in the invited and the control groups was compared with that for Swedish women in general the standardised mortality ratio was close to 100. CONCLUSIONS: The cause of death pattern in the invited group was, except for breast cancer, very similar to that in the control group, showing that the groups were comparable. Similarly, the total mortality including breast cancer mortality in the control group was almost identical to that in Swedish women in general. The same was true, with the exception of breast cancer, for the invited group. These observations confirm that the trial cohorts are representative of Swedish women and indicate that the quantitative results from these trials may safely be generalised to the Swedish populations.

Adult↗
PubMed1996

The Swedish randomised mammography screening trials: analysis of their effect on the breast cancer related excess mortality.

OBJECTIVE: To apply an indirect method for estimation of the breast cancer related excess mortality in the Swedish randomised mammography screening trials. SETTING: Randomised trials on mammography screening have, in Sweden, been performed in the counties of Kopparberg (W) and Ostergötland (E), the so called WE study, and in the three largest cities in Sweden, Stockholm (southern part), Gothenburg, and Malmö. An overview of the trials was presented in the Lancet in 1993 and included 156,911 women in the invited group and 125,866 in the control group. METHODS: The excess mortality in the breast cancer subgroups was estimated by indirect standardisation using official national cause of death statistics according to Statistics Sweden as a reference. RESULTS: The estimated reduction of the breast cancer related mortality was 24% for the whole group (40-74 years at randomisation). The corresponding figures for the age groups 40-49, 50-59, and 60-69 years were 6%, 28%, and 34% respectively. CONCLUSION: The results are very similar to those presented earlier based on the traditional comparison of the breast cancer mortality in the invited and in the control group. This analysis further strengthens previous reports on a beneficial effect of mammography screening, which is especially pronounced in the age group 50-69.

Adult↗
PubMed1996

Child mortality in a collapsing African society.

A cohort study of mortality among under-5-year-olds was carried out in two Somali villages in 1987-89, a period of economic and political collapse in the rural parts of the country. Analysed was the relative importance of the social characteristics for under-5-year-old mortality against a background of deteriorating political and economic conditions. Mortality increased among under-5-year-olds from 1987 (211 per 1000) to 1988 (323 per 1000) to 1989 (414 per 1000). The mortality risk was more pronounced for boys than girls and was more so for infants than children aged 1-4 years. The major signs prior to death were respiratory infections, diarrhoeal diseases, fever/malaria and tetanus in the neonatal period. Over the 3-year study period mortality rates for diarrhoeal diseases increased significantly, while those for respiratory infections and diseases preventable by immunization increased more slowly. The increasing trend in under-5-year-old mortality was more pronounced in instances when the mother derived her major income from sources other than farming and in larger households.

Child, Preschool↗
PubMed1995

Authentic standards for the reductive-cleavage method. The positional isomers of partially methylated and acetylated or benzoylated 1,5-anhydro-D-galactitol.

Described herein is an efficient method for the synthesis of the sixteen positional isomers of methylated and acetylated or benzoylated 1,5-anhydro-D-galactitol. The compounds are generated simultaneously by partial methylation of 1,5-anhydro-D-galactitol and subsequent benzoylation, and the individual isomers are obtained in pure form by high-performance liquid chromatography. Debenzoylation and acetylation yielded the desired acetates. Reported herein are the 1H NMR spectra of the benzoates and the electron-ionization mass spectra of the acetates and the tetra-O-methyl derivative. Also reported for the acetates and the tetra-O-methyl derivative are their linear temperature-programmed gas-liquid chromatography retention indices on three different capillary columns.

Acetylation↗
PubMed1995

Why do women report 'sick building symptoms' more often than men?

The prevalence of general, mucosal and skin symptoms compatible with the 'Sick Building Syndrome' (SBS) was studied in Swedish office workers. The marked excess in symptom prevalence among females, 12% SBS cases as compared to 4% among males, was analysed with respect to differences in biological or acquired risks and different illness and reporting (interview) behaviour among males and females. The distribution of risk indicators for symptoms was recorded in a questionnaire to 4943 employees. The skin symptom questions were validated in a clinical examination. Most risk indicators, such as paper work and psychosocial work load, had an unfavourable distribution for females. In the multivariate analysis however, female sex remained the most prominent risk indicator almost unaffected by the addition of other factors. Neither did effect modification contribute to the excess prevalence among females. The results from the clinical examination indicate that the excess symptom prevalence among females is real and not a reporting artefact. As the factors studied did not explain the excess symptom prevalence among females, the sex differential observed can be a reflection of a general excess of psychosomatic symptoms among women. Although inequalities in social conditions did not substantially explain the sex differential in symptom reporting, the importance of life situation and social roles should be further explored. As the studied variables are surrogates for actual measurements, another important issue is whether sex differences in working conditions, entailing different hierarchical positions in the office, have consequences for indoor air quality factors that are important for the symptoms. The study strongly underlines the importance of taking the sex distribution into account when surveying risk indicators for SBS symptoms.

Adult↗