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Biomedical subjects

S Janson

Publications and source records attributed to S Janson.

At least 37 records · Page 2Linked to original sources
PubMed2000

Biologic markers of airway inflammation in asthma.

Asthma is a serious chronic disease of the airways that affects approximately 14% of the population in the United States. The fundamental pathophysiologic component of asthma is airway narrowing, which causes airflow obstruction. Both inflammation and bronchoconstriction contribute to airway narrowing. The pathogenesis of airway inflammation in asthma and the natural history of the disease are the subject of intense research and study in many countries of the world. The mechanisms of airway inflammation are only partially understood but are the basis for the devastating symptoms that affect the quality of life of millions of people. Treatment of asthma is directed at decreasing airway inflammation to gain long-term control of the disease.

Asthma↗
PubMed2000

Ethnic differences: word descriptors used by African-American and white asthma patients during induced bronchoconstriction.

STUDY OBJECTIVES: To determine if African-American and white patients with asthma (1) differ in the words they use to describe their breathlessness, and (2) differ in their perception of breathlessness. DESIGN: Descriptive cross-sectional design. SETTING AND PARTICIPANTS: The study setting was located in Northern California, an ethnically and economically diverse area. A total of 32 subjects, 16 per group, completed the study. MEASUREMENTS: All had a provocation concentration of methacholine chloride causing a 30% fall in FEV(1) (PC(30)) of </= 8 mg/mL. Serial pulmonary function testing was performed. Breathlessness was measured using the Borg scale and the visual analog scale. Word descriptors were measured by an open-ended word descriptor questionnaire. RESULTS: Significant ethnic differences in the words used to describe the sensation of breathlessness were present at PC(30). African Americans used upper airway word descriptors: tight throat (p < 0. 0004), scared-agitated (p < 0.006), voice tight (p < 0.04), itchy throat (p < 0.03), and tough breath (p < 0.04). Whites used lower airway or chest-wall symptom descriptors: deep breath (p < 0.03), light-headed (p < 0.03), out of air (p < 0.01), aware of breathing (p < 0.03), and hurts to breathe (p < 0.06). In addition, African Americans required a significantly smaller, 44.3% (mean), dose of methacholine to achieve PC(30) (p < 0.02). CONCLUSION: This study provides valuable new information about ethnicity and the words used to describe breathlessness during airflow obstruction. Asthmatic African Americans used primarily upper airway word descriptors; whites used lower airway or chest-wall word descriptors. Effective symptom monitoring requires asking the correct question and awareness that ethnic differences in the words used to describe breathlessness may exist.

Administration, Inhalation↗
PubMed2000

Patients' perceptions of asthma control and impact on attitudes and self-management.

The objective of this work was to describe the incidence of chronic breathing problems, particularly asthma-related breathing problems, in a cross-section of the United States population and to assess the perceived impact of these problems on daily living. An initial screening survey was used in a nationwide panel of 30,000 households; an in-depth follow-up questionnaire was sent to a random sample of respondents who reported a breathing problem. A sample (n = 2,685) of respondents who reported persistent cough, shortness of breath, or wheezing within the previous 2 years were sent a newly developed questionnaire. A subsample (n = 723) of respondents reported a primary diagnosis of asthma and of these, 59.4% were female and 90.2% were white. Their mean age was 37.4 years. Respondents (n = 723) characterized their level of perceived asthma control as completely controlled, well controlled, somewhat controlled, or poorly/not controlled. At least 31% of those with a perception of some control and 59% of those with a perception of poor/no control reported their breathing problems had increased in the last year. Those who perceived their asthma-related breathing problems as poorly controlled reported significantly greater symptom frequency, activity restriction, fears and concerns about their breathing difficulties, less helpful coping strategies, and less confidence in their doctor's ability to care for them. Responses to many of the questions indicated that the worst levels of disease control were associated with poorer quality of life and a more negative perception of the disease and its effects on daily living. A significant portion of the U.S. population appears to suffer from chronic breathing problems; this requires confirmation and further exploration to reduce the potential mortality and morbidity due to asthma in the United States.

Activities of Daily Living↗
PubMed1999

Host specificity in the Richelia-diatom symbiosis revealed by hetR gene sequence analysis.

The filamentous heterocyst-forming cyanobacterium Richelia intracellularis forms associations with diatoms and is very abundant in tropical and subtropical seas. The genus Richelia contains only one species, R. intracellularis Schmidt, although it forms associations with several diatom genera and has considerable variation in size and morphology. The genetic diversity, and possible host specificity, within the genus Richelia is unknown. Using primers against hetR, a gene unique for filamentous cyanobacteria, specific polymerase chain reaction (PCR) products were obtained from natural populations of R. intracellularis filaments associated with three diatom genera. Phylogenetic analyses of these sequences showed that they were all in the same clade. This clade contained only the R. intracellularis sequences. The genetic affiliation of hetR sequences of R. intracellularis to those of other heterocystous cyanobacteria strongly suggests that it was not closely related to endosymbiotic Nostoc spp. hetR sequences. Sequences from R. intracellularis-Hemiaulus membranaceus sampled in the Atlantic and Pacific Oceans were almost identical, demonstrating that the genetic relatedness was not dependent on geographical location. All sequences displayed a deep divergence between symbionts from different genera and a high degree of host specificity.

Bacterial Proteins↗
PubMed1998

The presence and expression of hetR in the non-heterocystous cyanobacterium Symploca PCC 8002.

The filamentous cyanobacteria Symploca PCC 8002 (Symploca) and Trichodesmium spp. fix nitrogen aerobically in the light in a light/dark cycle, without forming specialized thick-walled cells (heterocysts). Even though they do not form heterocysts, we amplified and sequenced a segment of a key regulatory gene in heterocyst differentiation, the hetR gene, from Symploca, Trichodesmium erythraeum and Leptolyngbya PCC 73110 (which fixes nitrogen anaerobically) using degenerate oligonucleotides. The transcriptional level of hetR in Symploca PCC 8002 was examined in relation to nifH expression during nitrogen step-down. The expression pattern of hetR suggests that it was not induced during removal of combined nitrogen, as is the case with the heterocystous cyanobacteria. This is the first report of sequences corresponding to a portion of hetR from within the group of non-heterocystous cyanobacteria.

Acetylene↗
PubMed1998

Early postpartum discharge and subsequent breastfeeding.

BACKGROUND: Early postpartum discharge of babies was gradually introduced in Sweden in the 1980s on ideological grounds, based on the premise that maternity wards were unnatural settings for mothers and babies and hampered breastfeeding. From about 1990, early discharge was used as a means to reduce costs. The purpose of this study was to examine if mandated early discharge at Central Hospital of Karlstad, Sweden, influenced subsequent breastfeeding. METHOD: Breastfeeding outcomes of infants up to six months of age of all births in 1993 (n = 3231) were compared with the outcome of newborns in 1990 (n = 1462). RESULTS: Breastfeeding at six months postpartum continued to increase during the early 1990s for both healthy and sick infants, irrespective of whether or not they were discharged early. In infants born in 1995 the breastfeeding rate at six months was 64 percent for healthy newborns and 53 percent for sick newborns. CONCLUSION: Factors other than the time of discharge, most likely a positive change of attitude in society and vigorous introduction of the Baby Friendly Hospital Initiative, seem to have been more important for successful breastfeeding.

Adolescent↗
PubMed1998

Reasons for delay in seeking treatment for acute asthma: the patient's perspective.

Increased morbidity and mortality due to asthma suggested the need to investigate whether persons with asthma report delay in seeking medical care during acute asthma exacerbations and the reasons they gave for delay. We interviewed 95 asthmatic adults, 36 men and 59 women, using a critical incident technique to discover how patients responded to acute asthma symptom episodes. Subjects were interviewed once per month for a total of three interviews. All subjects had physician-diagnosed asthma for a mean of 16.8+/-14.5 years. Eighty-six percent of the sample (n=82) reported delay in seeking medical care for severe asthma symptoms. Seven reasons for delay were identified: uncertainty, disruption, minimization, fear of systemic corticosteroid, previous bad experiences in emergency departments, the need to "tough it out" alone, and economic reasons. Seventy-one subjects (86.5%) reported three or more reasons for delay. Thirteen subjects (16%) identified pivotal episodes in which they realized they could die from asthma and as a result, no longer delayed. People with asthma often delay seeking urgent care for acute episodes for a variety of reasons. Some of these reasons are modifiable. Clear directions from health professionals to guide patients in responding to acute asthma episodes are needed. Asthma action plans written by the primary physician may be a positive agent of change for those who delay.

Adrenal Cortex Hormones↗
PubMed1997

Providing asthma education in primary care practice.

An educational dialog founded on open communication between clinician and patient is necessary for a successful partnership in asthma care. Educating patients in self-management of asthma has become a major challenge in primary care practice. The process should begin at the time of diagnosis and should be integrated into every step of medical care during office visits and any other clinician-patient interaction. Identifying patients' expectations and concerns about their disease at each office visit helps the clinician focus care. The educational effort should include a discussion of basic asthma facts, and the types and uses of medications, and a demonstration of the skills involved in the proper use of metered-dose inhalers, spacers and peak flow meters. A written asthma self-management plan developed jointly by the clinician and the patient includes recommended daily medications and the specific steps the patient should take to control asthma and achieve the goals of asthma care.

Asthma↗
PubMed1994

Chronic illness in preschool Jordanian children.

This is a prevalence study of chronic illness and disability in Jordanian children 0-7 years of age living in Sweileh, a suburb of Amman. The study was performed in 1991. A total number of 2528 children were examined, representing more than 95% of the children 0-7 years in the catchment area. Of these, 198 (7.8%) had a disability or a chronic disease. Fifty-eight children (2.6%) were classified as moderately or severely affected. Boys were in the majority. Compared with the findings in European and American studies, congenital eye diseases and severe mental retardation were common while atopic diseases were rare. Consanguinity seemed to be important in the aetiology of chronic diseases. Social background factors did not have a substantial impact on the overall prevalence, but psychomotor delay and a sequel to an injury were more common in children from poor families.

Cerebral Palsy↗
PubMed1994

Accident risks for suburban preschool Jordanian children.

This exploratory investigation of child accidents in suburban Jordan 1988-1991 indicated that children were daily exposed to fire, drugs, and chemical agents, and played in dangerous places. Children under 2 years of age were frequently burned, and those slightly older injured through falls and cuts. Boys were more accident-prone than girls in accordance with practically all previous world-wide studies. The overall accident picture was similar to European reports from 50 years ago. Many environmental hazards could be explained as being a consequence of relative poverty, but parent's awareness of accident risks for children was low, even among well educated people. Strategies to diminish accident risks for pre-school children are suggested.

Accidents↗