A rat model of otitis media with effusion caused by eustachian tube obstruction with and without Streptococcus pneumoniae infection: methods and disease course.

OBJECTIVE: To describe the clinical and histopathologic progression of a rat model of otitis media with effusion caused by eustachian tube obstruction (ETO) with and without Streptococcus pneumoniae infection. METHODS: In 164 rats, the left, bony eustachian tube was approached via a ventral incision and obstructed with dental material. Then 108 rats were infected via an intrabullar injection with S pneumoniae. At 48 hours, the infected rats were treated for 5 days with ampicillin. All ears were evaluated by weekly otomicroscopy. On each of days 1, 2, 7, 21, 35, 56, and 112, four rats were killed for histologic study. All effusions were cultured for bacteria. RESULTS: Fourteen rats died of surgical complications; effusion resolved by 2 weeks in 9 rats. During the first few days, infected ears with ETO had bulging tympanic membranes, followed by tympanic membrane retraction, purulent effusion, and otorrhea (50%) over the next few weeks, whereas uninfected ears with ETO developed retraction and serous effusion during the same time frame. At later times, all ears with ETO presented with retraction and serous or serous-mucoid effusion. S pneumoniae was recovered only from the infected ears with ETO (days 1 and 2), with some colonization by nonpathogenic microorganisms observed equally in both groups of ears. Histology showed a typical acute inflammatory reaction in the challenged ears with ETO through day 14 and then a chronic inflammation for all ears with ETO. CONCLUSION: The experimental methods provoked reproducible pathologic signs similar to those for otitis media with effusion. Given the availability of rat-specific reagents, this model is well suited for studies of cytokine elaboration during disease pathogenesis.     

Differences in the appraisal of health between aged and middle-aged adults

This study examines whether the aged and the middle aged differ in their self-appraisal of health. Data were obtained through interviews and medical records from a probability sample of 460 individuals aged 45 to 89 years old. The aged evaluated their health more pessimistically than the middle aged, after controlling for physical health, psychological distress, gender, and education. The aged's perception of health was significantly worse than the middle aged's for persons having diagnoses in each of the following diagnostic categories: rheumatism and musculoskeletal deformities, nervous system and sense disorders, and digestive problems. A stronger association was found between perceived poor health and depressive symptoms among the aged than the middle aged. The importance of psychological distress on the aged's health assessment and subsequent illness behaviors is discussed.     

Intussesception after jejunoileal bypass as diagnosed by ultrasound

Eighty patients who had undergone jejunoileal bypass for morbid obesity were examined by ultrasound at their routine follow-up visits to the clinic. Ultrasonographic evidence of intestinal intussusception was found in 15 patients (19%). Two of these patients were asymptomatic. Ultrasonographic findings were confirmed by operation in 6 patients (5 with intussusception, 1 negative).     

Perceived control of asthma and quality of life among adults with asthma.

BACKGROUND: Perceived control of certain chronic conditions influences health status outcomes. OBJECTIVE: To explore the impact of perceived control of asthma on asthma-specific and generic health status outcomes among adults with asthma. Perceived control was defined as individuals' perceptions of their ability to deal with asthma and its exacerbations. METHODS: Data were drawn from the baseline and first two followups of a longitudinal study of adults with asthma surveyed by telephone at 18-month intervals. An 11-item questionnaire (Perceived Control of Asthma Questionnaire [PCAQ]) was developed and validated. RESULTS: The PCAQ demonstrated high internal consistency (Cronbach's alpha = 0.79). Greater perceived control was associated with less severe asthma, greater asthma self-efficacy, lower perceived asthma severity, lower perceived danger from asthma, and greater perceived usefulness of asthma medicines. Greater perceived control was significantly associated with better asthma-specific quality of life concurrently and 18 and 36 months later, after controlling for demographics, smoking, and severity of asthma. Greater perceived control as also significantly associated with generic mental health outcomes concurrently and 18 and 36 months later, after controlling for covariates. Perceived control was associated with physical function concurrently and 18 months later, but not 36 months later. CONCLUSIONS: The PCAQ is a reliable and valid measure of perceived control of asthma. Perceived control of asthma was associated with both asthma-specific and generic health status outcomes, concurrently and predictively. If perceived control could be modified, better outcomes, particularly better psychologic outcomes, might be achieved for individuals with asthma.     

Determinants of perceived health status of medical outpatients.

The aim of this study was to examine the relative contributions made by medical morbidity, psychiatric disorder, functional status, and hypochondriacal attitudes to medical patients' opinions of their overall health status. The study was conducted in the general medical clinic of a large academic teaching hospital. Consecutive clinic visitors on randomly selected days were screened with a hypochondriasis self-report questionnaire, since the overall project was designed as a study of hypochondriasis. A random sample of the patients below a pre-established cutoff (n = 100), along with all those exceeding the cutoff (n = 88), returned to undergo a research battery. For this analysis, a representative sample of the entire clinic was reconstituted by weighting the data from patients above and below the screening cutoff in proportion to their prevalence in the clinic. Measures of psychiatric disorder (the Diagnostic Interview Schedule), personality disorder, functional status and disability, medical morbidity (from physician ratings and medical record audit), and hypochondriacal attitudes were obtained. Patient self-ratings of global health status were significantly correlated with aggregate medical morbidity (r = 0.36; P less than 0.001); psychiatric morbidity (r = 0.48; P less than 0.001); functional disability (for intermediate activities of daily living, r = 0.62; P less than 0.001); hypochondriacal attitudes (r = 0.79; P less than 0.001); and with the tendency to somatize (r = 0.77; P less than 0.001). Using multiple regression analysis, the most powerful correlates of perceived global health were hypochondriasis, somatization and disability (model R2 = 0.762).(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of food restriction and refeeding on adipocyte glucose metabolism in Zucker rats

Chronic food restriction has been shown to enhance glucose metabolism in adipocytes from lean Zucker rats at 10, 26, and 52 weeks of age compared to ad libitum-fed lean rats. Only adipocytes from food restricted 10-week-old obese rats demonstrated this response. In this study, lean and obese rats were food restricted from 5 until 14 weeks of age to determine the age at which adipocytes from obese rats were no longer affected by this intervention. Effects of 1 week of refeeding were also determined. When the rats were killed, body weights were highest in control rats followed by restricted/refed and then restricted rats within each genotype. Epididymal pad weights of lean rats were resistant to dietary intervention, while those of obese-restricted and obese-restricted/refed rats weighed less than pads of obese-control rats. Retroperitoneal pad weight was lowered by food restriction in both genotypes; but only that of lean-restricted/refed rats totally recovered with refeeding. Adipocytes of lean-restricted rats had the highest conversion of glucose to CO₂. Glyceride-glycerol production was higher in obese compared to lean rats, but restricted rats had elevated conversion of glucose to fatty acids. In general, these results indicate that by 14 weeks of age obese Zucker rats no longer respond to food restriction with an elevated rate of glucose metabolism in adipocytes.     

Informational needs of individuals and families with hereditary cancers

Individuals and families with hereditary cancers have informational needs that differ, depending on the availability of testing for increased hereditary risk and major focus of concern (reproductive decision-making or risk to self). Cancer risk counseling helps individuals understand risk information so they can make decisions appropriate to their lives and value systems.     

Virulent human strains of group G streptococci express a C5a peptidase enzyme similar to that produced by group A streptococci.

Specific proteolytic destruction of the human chemotaxin, C5a, is a property of group A and B streptococcal pathogens. Here we show that virulent group G streptococci from human sources also express C5a peptidase activity. The enzyme responsible for this activity is approximately the same size as and is antigenically similar to that produced by group A streptococci. On the basis of Southern hybridization analysis with an internal fragment of the group A C5a peptidase gene (scpA) as a probe, a copy of this gene was found in the genome of all group G human isolates tested. Comparison of partial restriction maps of scpA and scpG revealed significant similarity between the two genes. Group G strains isolated from dogs and cows were found to lack C5a peptidase activity and did not hybridize to the scpA-specific probe. The association of this activity with three streptococcal species suggests that elimination of phagocyte chemotactic attractants is a more universal virulence mechanism than originally anticipated.