Ultrastructural features of alveolar cells in experimental hypersensitivity pneumonitis

An experimental model of hypersensitivity pneumonitis in rats was used to analyze ultrastructural changes in cellular elements of the epithelium and alveolar lumen, in an attempt to correlate the immunological mechanisms responsible for these pulmonary lesions. Semifine and ultrafine sections of pulmonary tissue of immunized and intratracheally challenged rats were analyzed and compared with their respective controls. A thickening of the alveolar walls and an increase in the number of macrophages and type II pneumocytes were observed in the semifine sections. The ultrastructural examination revealed appreciable changes in morphology, size and location of both types of cells. The membranes of the macrophages showed evident alterations and the type II pneumocytes, an increase in size and number of cytoplasmic inclusions corresponding to surfactant. The cellular changes observed are consistent with phenomena of cellular activation, which can be attributed to the release of soluble mediators by T lymphocytes. The important delayed hypersensitivity phenomena based on the morphology of pulmonary lesions in this model contribute data to the pathogenic interpretation of hypersensitivity alveolitis.     

The impact of medical informatics on the confidence of rural physicians caring for patients with chronic hepatitis C viral infections.

OBJECTIVE: The purpose of the present study was to determine whether CD-based medical informatics enhances rural physicians' confidence in the management of patients with chronic hepatitis C viral infections. METHODS: A total of 385 Canadian rural physicians were mailed a CD-based medical software programme that outlines all aspects of HCV care including diagnosis, counselling, treatment and follow-up. Accompanying the CD was a brief questionnaire that addressed physicians' confidence in the following areas: (i) identifying HCV patients in their practice; (ii) laboratory use and interpretation; (iii) patient counselling; (iv) selection of candidates for treatment; (v) sharing treatment delivery; and (vi) providing follow-up. Three months thereafter, the same questionnaire was repeated. RESULTS: Of the 385 mailings, 59 (15%) physicians returned the initial questionnaire and 57 (15%) the follow-up questionnaire. Twenty-five (44%) respondents indicated they had used the CD. Baseline physician confidence was low in three of the six areas addressed. At follow-up, in addition to now being confident in all areas, CD users were significantly more confident than those who had not used the CD. Increases in physician confidence for CD users were approximately 150-300% in the six areas addressed. The value assigned the CD programme was 8/10. CONCLUSION: The results of this study indicate that: (i) rural physicians are uncomfortable in dealing with many aspects of HCV management; (ii) CD-ROM-based medical informatics can significantly enhance rural physicians' confidence in these areas; (iii) approximately 50% of physicians will employ CD-ROM-based medical informatics in their offices; and (iv) physician level of satisfaction with such programmes is high.     

Relationships between scores on the COMLEX-USA Level 2-Performance Evaluation and selected school-based performance measures

The Comprehensive Osteopathic Medical Licensing Examination USA Level 2 Performance Evaluation (COMLEX-USA Level 2-PE) is a national multistation performance examination designed to examine students' osteopathic clinical skills. The current study examines the relationship between achievement levels on the COMLEX-USA Level 2-PE and selected school-related variables for the class of 2005 at the West Virginia School of Osteopathic Medicine in Lewisburg, WVa (N=70). Significant (P<.01) correlations between the COMLEX-USA Level 2-PE summary performance and selected academic achievement measures include: weighted Physical Diagnosis grade, 0.41; weighted year 1 and year 2 Osteopathic Principles and Practice grade, 0.37: overall year 2 grade point average, 0.42; the objective structured clinical evaluation (OSCE) Physical Examination score, 0.40; and the OSCE Total Station score, 0.33. While further research is needed, the current study found modest but notable relationships between school-generated academic variables and performance on the COMLEX-USA Level 2-PE, and therefore supports the validity of the COMLEX-USA Level 2-PE examination for assessing the clinical skills of future osteopathic physicians.     

Magnetic resonance imaging and head circumference study of brain size in autism: birth through age 2 years

CONTEXT: While the neuroanatomical basis of autism is not yet known, evidence suggests that brain enlargement may be characteristic of this disorder. Inferences about the timing of brain enlargement have recently come from studies of head circumference (HC). OBJECTIVES: To examine brain volume and HC in individuals with autism as compared with control individuals. DESIGN: A cross-sectional study of brain volume was conducted at the first time point in an ongoing longitudinal magnetic resonance imaging study of brain development in autism. Retrospective longitudinal HC measurements were gathered from medical records on a larger sample of individuals with autism and local control individuals. SETTING: Clinical research center. PARTICIPANTS: The magnetic resonance imaging study included 51 children with autism and 25 control children between 18 and 35 months of age (the latter included both developmentally delayed and typically developing children). Retrospective, longitudinal HC data were examined from birth to age 3 years in 113 children with autism and 189 local control children. MAIN OUTCOME MEASURES: Cerebral cortical (including cortical lobes) and cerebellar gray and white matter magnetic resonance imaging brain volumes as well as retrospective HC data from medical records were studied. RESULTS: Significant enlargement was detected in cerebral cortical volumes but not cerebellar volumes in individuals with autism. Enlargement was present in both white and gray matter, and it was generalized throughout the cerebral cortex. Head circumference appears normal at birth, with a significantly increased rate of HC growth appearing to begin around 12 months of age. CONCLUSIONS: Generalized enlargement of gray and white matter cerebral volumes, but not cerebellar volumes, are present at 2 years of age in autism. Indirect evidence suggests that this increased rate of brain growth in autism may have its onset postnatally in the latter part of the first year of life.     

Assessing the ability of medical students to perform osteopathic manipulative treatment techniques

While osteopathic and allopathic medicine share many commonalities, there are key practice-based differences that uniquely characterize the two professions. For osteopathic medicine, one such defining feature is the use of osteopathic manipulative treatment (OMT). Unfortunately, while various treatment modalities are taught in osteopathic medical schools, there has been relatively little work done to establish standardized evaluation protocols. The purpose of this investigation was to explore the use of OMT assessment in the context of a multistation standardized patient examination. Analysis of performance data from 121 fourth-year osteopathic medical students indicated that the ability to do OMT can be reliably and validly assessed using a combination of simulated patient encounters, trained osteopathic physician raters, and an objective rating tool. Additional studies that incorporate a larger sample of students and focus on modifications to the assessment tool and rating protocols are warranted.     

Polycystic ovarian syndrome and insulin resistance in white and Mexican American women: a comparison of two distinct populations

OBJECTIVES: We sought to determine what differences, if any, existed between white and Mexican American women with polycystic ovary syndrome (PCOS) and whether the same values for fasting insulin, fasting glucose/insulin ratio, and homeostasis model assessment (HOMA) might be applied when screening both ethnic groups for insulin resistance. STUDY DESIGN: Eighty-three consecutive women suspected to have PCOS but who demonstrated absence of other endocrine disorders comprised the study population. Nineteen healthy ovulatory women volunteered as controls. Fasting serum samples were obtained for determination of thyroid-stimulating hormone (TSH), prolactin, glucose, insulin, free and total testosterone, 17-hydroxyprogesterone, and dehydroepiandrosterone sulfate in the early proliferative phase. An oral glucose load was administered, and blood samples for glucose and insulin were drawn at 1, 2, and 3 hours. Those with impaired glucose tolerance or diabetes mellitus were excluded from our final study population. Four different groups were defined: (1) women with PCOS and insulin resistance, (2) women with PCOS without insulin resistance, (3) women with irregular cycles but without PCOS or another identifiable endocrinopathy, and (4) regular, cycling control subjects. Each group was subdivided by ethnicity (white or Mexican American). A total of 65 white and 37 Mexican American women were studied, including control subjects. RESULTS: Among all study participants, Mexican American women with PCOS had significantly higher mean values for body mass index, fasting insulin, and HOMA but lower mean fasting glucose/insulin levels than white women. When group 1 patients (PCOS with insulin resistance) were compared between ethnic groups, mean fasting insulin and HOMA levels were significantly lower and glucose/insulin ratios higher in white than in Mexican American women. A single cutoff value for insulin resistance in PCOS was insensitive when applied to both ethnic groups. A fasting insulin value >20 microU/mL, HOMA value > 3.8, and glucose/insulin value <7.2 were reasonable screening values in our population of white women, whereas a fasting insulin value >23 microU/mL, HOMA value >4.5, and glucose/insulin ratio <4.0 were feasible screening values in Mexican American women. CONCLUSIONS: We conclude that (1) Mexican American women with PCOS are more insulin resistant than white women, (2) the incidence of insulin resistance is higher in Mexican American women with PCOS than in white women, (3) a single "screening" value for PCOS-related insulin resistance screening cannot be applied to both white and Mexican American women, and (4) normative values for insulin resistance screening in the PCOS population should be individualized for different racial or ethnic populations.     

Variability of serum estrogens among postmenopausal women treated with the same transdermal estrogen therapy and the effect on androgens and sex hormone binding globulin

OBJECTIVE: To examine the variability of serum estrogens in response to transdermal estrogen replacement therapy (ET), and to determine the effects on androgens and sex hormone binding globulin (SHBG). DESIGN: Randomized, double-blind, placebo-controlled study. SETTING: Women's hospital. PATIENT(S): Two groups of postmenopausal women: [1] 21 women not on ET enrolled and 17 completed the study; [2] 19 women on continuous transdermal ET enrolled and 13 completed the study. INTERVENTION(S): Women not on ET were administered a placebo patch or a newly initiated estrogen patch, then crossed over to the alternate treatment. Serum samples were obtained at baseline and the subsequent 3 days from the placebo and new-patch groups and from a separate group of women receiving continuous estrogen patch treatment. MAIN OUTCOME MEASURE(S): Estradiol (E(2)), estrone, estrone sulfate, T, dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), androstenedione, free androgen index, and SHBG. RESULT(S): There was considerable intrapatient and interpatient variability in the estrogen response to identical treatment doses, with E(2) values differing between women as much as 138 pg/mL and E(2) increases above baseline differing as much as 90 pg/mL. Continuous treatment increased SHBG and decreased androstenedione levels; however, levels of T, DHEA, DHEAS, and free androgen index did not change. CONCLUSION(S): There is great variability of estrogen in response to transdermal ET, but minimal effect on circulating androgens.     

Pelvic imaging with a selenium-based detector (Thoravision). Comparison with screen-film radiography in 75 patients

OBJECTIVE: To evaluate whether the selenium detector (Thoravision) provides sufficient diagnostic confidence in digital pelvic imaging compared with a conventional screen-film combination. METHODS: In 75 patients, pelvic imaging with conventional screen-film and isodose selenium radiography using a dedicated postprocessing mode was compared independently by three radiologists. The depiction of cortical and cancellous bone was evaluated in the iliac wings, sacral and pubic bones, acetabulum, femoral head, and trochanter. Demarcation of soft tissue was assessed in the iliac and trochanteric region. RESULTS: Visualization of cortical bone and soft tissue in the iliac area as well as soft tissue and cortical and cancellous bone in the trochanteric region was significantly superior with the selenium detector. However, conventional imaging was better in the trabecular bone of the sacral region, where results with the selenium system were particularly poor. CONCLUSIONS: The selenium detector (Thoravision) is advantageous in imaging soft tissue adjacent to the iliac wings and the trochanter, but results for the cancellous sacral bone are poor. Further modifications of postprocessing modes may lead to improved depiction of this critical pelvic area.