Bronchial thermoplasty increases airway volume measured by functional respiratory imaging.

BACKGROUND: The purpose of this study was to use CT scanning with computational fluid dynamics to evaluate the mechanisms by which Bronchial Thermoplasty (BT) improves asthmatic symptoms. METHODS: The study was conducted in a university teaching hospital, experienced in performing BT. Imaging studies were performed before, and after, BT of the left lung, and prior to treatment of the right lung, which therefore acted as a control. On each occasion, two high-resolution CT scans were performed, one at full inspiration (TLC) and the other at Functional Residual Capacity (FRC). The study protocol was offered to 10 patients, all of whom met the definition of severe asthma, despite high dose inhaled corticosteroids and dual long acting bronchodilators. RESULTS: Significant increases in airway luminal volume were observed on the treated side, compared with control, at both full inspiration (by 27%) and at FRC (by 17%). The ratio of distal airway volume to lung volume significantly increased on the treated side. The change in airway volume with inspiration from FRC increased by 48% on the treated side compared to 5% in the control lung, suggesting treatment increased airway distensibility. No effect was observed on airway wall thickness, nor air trapping. There was a trend towards correlation between the improvement in airway volume at TLC and improvement in symptoms. CONCLUSION: This study demonstrates that BT increases the luminal airway volume on the treated side compared to the control lung. We suggest that this is an important link between the airway smooth muscle atrophy demonstrated pathologically, and the improvement in symptoms observed clinically.

Venous leg ulceration: skin and serum zinc concentrations.

Zinc was measured in serum and in thigh skin in patients with venous leg ulceration and also in controls. Skin zinc concentrations were expressed in terms of area and dry weight. The mean serum zinc concentration was significantly lowered in the ulcer group. The thigh skin zinc concentration was elevated in patients with chronic venous leg ulceration. The difference was more marked if the zinc concentration was calculated per surface area of skin, but did not reach statistical significance.

Trophic skin ulceration of leprosy: skin and serum zinc concentrations.

Skin and serum zinc measurements have been made in patients with leprosy with and without trophic skin ulceration and in several other groups. Serum zinc concentrations were decreased in leprosy irrespective of the presence or absence of skin ulceration. Serum zinc concentrations in leprosy were also unrelated to smears positive for Mycobacterium leprae and to the clinical type of leprosy. Since a decrease of the serum zinc was also found in patients with dermatitis herpetiformis and pulmonary tuberculosis it seems likely that the decreased serum zinc in leprosy is a nonspecific metabolic consequence of chronic skin and internal disease. The mean skin zinc concentration in leprosy did not differ significantly from the corresponding value in control subjects, the lack of agreement between serum and skin concentrations being possibly related to the presence of nonexchangeable keratin-bound zinc in skin. Though the clinical significance of lowered serum zinc concentrations in leprosy is uncertain therapeutic trials of zinc treatment in leprosy with trophic skin ulceration seem justifiable.

Mast cell population density, blood vessel density and histamine content in normal human skin.

Mast cell population density was determined in normal skin from two regions of the arm of several healthy men and compared with blood vessel density and histamine concentration in the same sites. Mast cell and blood vessel counts were made in 1--1.5 micrometer thick plastic sections, by light microscopy and tissue-histamine concentrations were determined by automated fluorimetric analysis. Statistically significant correlations were found between mast cell counts, blood vessel counts and histamine content in skin from the upper arm but no similar correlations were obtained in the forearm. Anatomical differences between the two sites may have been the cause of this discrepancy. Wide variations in mast cell counts and blood vessel density were found in different sections from the same biopsy samples which confirms the notion that dermal mast cells are unevenly distributed. Analysis of variance of the mast cell counts showed that the variance between sections from different blocks from the same biopsy samples was greater than the variance between adjacent biopsies. There was also a marked variation in the histamine content between biopsy samples from sites only 2 cm apart in the same subject.

Identification of spouses at high risk during bereavement: a preliminary assessment of Parkes and Weiss' Risk Index.

The Risk Index developed by Parkes and Weiss (1983) is a brief structured assessment tool for identifying bereaved spouses who may be at high risk for developing complications during bereavement. The present study was undertaken to evaluate the utility of the Risk Index in predicting outcome during the first year of bereavement in spouses of deceased hospice patients. Professional staff at the hospice completed the Risk Index shortly after the spouse died and outcome was then assessed after 1, 3, 6, and 12 months. High-risk bereaved were younger than low-risk bereaved. Number of young children at home, existence of close relationships, and financial status were important predictors of outcome during the first year of bereavement. The findings suggest that the Risk Index may serve as a cost-effective means of assessing risk for complications during the first year of bereavement.