Expression of α5 (CD49e) and α6 (CD49f) Integrin Subunits on T Cells in the Circulation and the Lamina Propria of Normal and Inflammatory Bowel Disease Colonic Mucosa

Intestinal lamina propria T cells are believed to be derived, via the systemic circulation, from gut-associated lymphoid tissue. After migration into the lamina propria, T cells are capable of luminally directed migration following the loss of surface epithelial cells. For adhesion and migration within the extracellular matrix, T cells are likely to utilize the integrin family of adhesion molecules. The aim of this study was to quantitatively and qualitatively investigate the expression of α₅ and α₆ integrin subunits on the surface of human T cells that: (a) migrated out of the lamina propria, (b) remained resident within the matrix and (c) were present in the circulation. In both subpopulations of CD4 and CD8-positive T cells, from both normal and inflamed (inflammatory bowel disease) colonic mucosa, there were significantly fewer α₅ and α₆-positive cells than in the peripheral blood. In addition, there were significantly fewer α₆ integrin molecules on the surface of CD4 and CD8-positive lamina propria T-cell subpopulations, compared with those in the circulation. Our studies suggest that, following migration into the lamina propria, there is down-regulation of α₅ and α₆ integrin-subunit expression on the surface of T cells. Molecules other than members of very late activation antigen-5 (VLA-5) (α₅β₁) and VLA-6 (α₆β₁) families of adhesion molecules are likely to be important in interactions with extracellular components in the lamina propria of normal and inflamed human colonic mucosa.     

Why employers need to rethink how they buy health care

Employers will continue to have a key role in the U.S. health system. Unfortunately, their purchasing practices have fallen far short of ideal. Large employers can lead the way for smaller companies, but by not routinely using competitive bidding or integrating quality into their specifications, they have sent mixed messages to both health plans and providers. Employers need to either get serious about buying health care as individual companies or explore other options. To purchase effectively, both health care expertise and the sustained commitment of senior leadership are needed. Whether employers can reverse their historical performance and become better purchasers is an open question.     

Peribronchiolar metaplasia: a common histologic lesion in diffuse lung disease and a rare cause of interstitial lung disease: clinicopathologic features of 15 cases

Peribronchiolar metaplasia (PBM) is a histologic lesion consisting of peribronchiolar metaplasia (PBM) of bronchiolar-type epithelium. Although widely recognized, PBM has received little attention in the pathologic literature and is not known to have clinical significance. We identified 15 cases in which PBM was the only major histologic finding in surgical lung biopsies from patients with interstitial lung disease (PBM-ILD), and we reviewed the clinical, imaging, and pathologic findings. The mean age was 57 years (range, 44-74 years) with 13 females and 2 males. One patient had been a welder with fume and asbestos exposure; another had pigeon exposure. Smoking history was available for 13 patients: three current smokers, one cocaine user, two former smokers, and seven never smokers. Three patients had collagen vascular disease. One had elevated serum antinuclear antibody titers. Pulmonary function data were available for 10 patients: one obstructive, five restrictive, two mixed obstructive and restrictive, and two normal. Computerized tomography in 7 patients showed mosaic attenuation in 3 patients and air trapping in 1 patient; no bronchiectasis, septal lines, or honeycombing were seen in any cases. All 11 patients with available follow-up are alive; 4 of them have experienced symptomatic improvement (follow-up, 0.6-6.9 years; mean, 2.4 years). PBM was found focally in other interstitial lung diseases, which were assessed for this lesion: 59% of usual interstitial pneumonia (17 of 29), 50% of nonspecific interstitial pneumonia (10 of 20), desquamative interstitial pneumonia (3 of 6), hypersensitivity pneumonitis (9 of 18), and 11% of respiratory bronchiolitis (2 of 18). In summary, PBM is a common histologic finding in various interstitial lung disorders. It is rarely the sole major lung biopsy finding in patients presenting with interstitial lung disease (PBM-ILD). Patients are mostly older women, with mild symptoms and CT findings. Survival appears to be favorable.     

Alterations in Vertebral Growth Following Prolonged Plaster Immobilisation

Long-term immobilisation in serial plasters for scoliosis, including the period of the adolescent growth spurt, leads to an increase in height of the vertebral bodies and a decrease of their height to width ratio. These changes are at the expense of the disc which is reduced in thickness. This stimulating effect on the vertebral body growth is probably due to the changes in mechanical forces.     

Utilization and yield of EEG in the elderly population.

The EEG is a common test ordered in the elderly population for a variety of indications such as syncope, encephalopathic states, transient unresponsive episodes, and clinical seizures. The authors analyzed the spectrum of EEG abnormalities in a series of 300 homogenous elderly patients in the southern region of Ireland who were referred for the above indications. Generalized slowing was seen in 30.7% and focal abnormalities in 9% of records. Thirteen records demonstrated focal sharp waves and one record showed generalized epileptiform discharges. Two records with seizures were identified, both with nonconvulsive status epilepticus. The incidence of ECG abnormalities was high (23%). In patients referred for syncope, the incidence of EEG epileptiform abnormalities (sharp waves) was 3%, in contrast to previous reports of 49%. In patients older than 80 years (the "old old"), EEG abnormalities were more common. The yield of the EEG for common referrals such as syncope, encephalopathy, and transient unresponsiveness is low for focal abnormalities. Electrocardiographic abnormalities were common and should be identified and treated appropriately.     

Idiopathic interstitial pneumonias: CT features

Idiopathic interstitial pneumonias comprise usual interstitial pneumonia (UIP), nonspecific interstitial pneumonia (NSIP), desquamative interstitial pneumonia (DIP), respiratory bronchiolitis-associated interstitial lung disease (RB-ILD), cryptogenic organizing pneumonia (COP), acute interstitial pneumonia (AIP), and lymphoid interstitial pneumonia (LIP). Each of these entities has a typical imaging and histologic pattern, although in practice the imaging patterns may be variable. Each entity may be idiopathic or may be secondary to a recognizable cause such as collagen vascular disease or inhalational exposure. The diagnosis of idiopathic interstitial pneumonia is made by means of correlation of clinical, imaging, and pathologic features. The characteristic computed tomographic (CT) features of UIP are predominantly basal and peripheral reticular pattern with honeycombing and traction bronchiectasis. NSIP is characterized by predominantly basal ground-glass opacity and/or reticular pattern, often with traction bronchiectasis. DIP and RB-ILD are smoking-related lung diseases characterized by ground-glass opacity and centrilobular nodules. COP is characterized by patchy peripheral or peribronchovascular consolidation. AIP manifests as diffuse lung consolidation and ground-glass opacity. LIP is associated with a CT pattern of ground-glass opacity sometimes associated with perivascular cysts.