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D Sittig

Publications and source records attributed to D Sittig.

6 recordsLinked to original sources
PubMed2000

Expression and regulation of regulated on activation, normal T cells expressed and secreted in thyroid tissue of patients with Graves' disease and thyroid autonomy and in thyroid-derived cell populations.

Thyroid glands affected by Graves' disease (GD) show striking lymphocytic infiltration, mainly by CD45RO(+) T cells. The mechanisms by which the various lymphocytic subsets are recruited and maintained in the thyroid are unknown. RANTES (regulated on activation, normal T cells expressed and secreted) in interaction with its receptors (CCR1, CCR3, CCR4 and CCR5) may be one of the favorite chemokines involved in the cell trafficking and maintenance. RANTES messenger RNA (mRNA) was quantified in the thyroid tissue of 16 patients with GD and 7 patients with thyroid autonomy (TA), using competitive RT-PCR. We found a clear correlation between the RANTES mRNA level and 1) the degree of T-cell infiltration (r = 0.68), and 2) the level of serum antibodies to thyroid peroxidase (r = 0.76) in GD but not in TA patients. There was no difference between the autonomous nodules and the quiescent surrounding tissue in TA patients. To define the cellular source of RANTES mRNA and protein, we examined various thyroid-derived cells. Lymphocytes showed a markedly higher basal RANTES mRNA and protein level (mean +/- SEM; pg/mL, n = 3; 140 +/- 30) than thyrocytes (12 +/- 5) and fibroblasts (9 +/- 2). Lymphocyte stimulation with PMA enhanced RANTES secretion significantly (4490 +/- 200). Fibroblasts responded to stimulation with interleukin 1 (530 +/- 220) and tumor necrosis factor alpha (2780 +/- 1790), whereas thyrocytes did not. However, some thyroid carcinoma cell lines showed very high basal and stimulated RANTES expression. Lymphocytes expressed the mRNA of all chemokine receptors that bind RANTES. The number of CCR3(+) and CCR5(+) T cells was significantly higher in thyroid-derived leukocytes than in those in the peripheral blood stream. We conclude that RANTES expression, mainly by lymphocytes, is perhaps involved in the maintenance of lymphocytic infiltration and, therefore, in the autoimmune responses in GD.

Cells, Cultured↗
PubMed1998

Measuring and improving quality using information systems.

Information systems (IS) are increasingly important for measuring and improving quality. In this paper, we describe our integrated delivery system's plan for and experiences with measuring and improving quality using IS. Our approach is that for quality measurement to be practical, it must be integrated with the routine provision of care, and whenever possible should be done using IS. Thus, at one hospital, we now perform almost all quality measurement using IS. However, IS are not only useful for measuring care, but represent powerful tools for improving care using decision support. Specific areas in which IS has already been particularly effective include reducing the unnecessary use of laboratory testing, reporting important abnormalities to key providers rapidly, adverse drug event detection and prevention, initiatives to reduce the costs of drugs, and making critical pathways available to providers. The next wave of effort will be to promote widespread use of computerized guidelines, which is likely to prove more challenging. However, the advent of managed care in the U.S. has produced strong incentives to provide high quality care at low cost, and our perspective is that only with better IS than exist today will this be possible on a widespread basis. Such systems make feasible implementation of care improvement and cost reduction initiatives on a scale which could not previously be considered.

Decision Making, Computer-Assisted↗
PubMed1992

Transesophageal color flow Doppler imaging for aortic insufficiency in patients having cardiac operations.

Transesophageal color flow Doppler findings were studied in 30 patients with aortic insufficiency who had cardiac operations. Measurements were expressed as ratios of corresponding left ventricular outflow tract dimensions. Regurgitant jet proximal width ratio was significantly related to jet area ratio (r = 0.92) and correlated poorly with the degree of jet penetration into the left ventricular cavity (r = 0.32). The vectors of the regurgitant jets were variable. Nine patients had undergone aortography. Regurgitant jet proximal width and area ratios were significantly related to angiographic grade (r = 0.88 and 0.87, respectively) in these patients. We concluded that the esophagus offers a satisfactory transducer orientation for color flow Doppler assessment of aortic insufficiency.

Adult↗
PubMedDate not supplied

Using information systems to measure and improve quality.

Information systems (IS) are increasingly important for measuring and improving quality. In this paper, we describe our integrated delivery system's plan for and experiences with measuring and improving quality using IS. Our belief is that for quality measurement to be practical, it must be integrated with the routine provision of care and whenever possible should be done using IS. Thus, at one hospital, we now perform almost all quality measurement using IS. We are also building a clinical data warehouse, which will serve as a repository for quality information across the network. However, IS are not only useful for measuring care, but also represent powerful tools for improving care using decision support. Specific areas in which we have already seen significant benefit include reducing the unnecessary use of laboratory testing, reporting important abnormalities to key providers rapidly, prevention and detection of adverse drug events, initiatives to change prescribing patterns to reduce drug costs and making critical pathways available to providers. Our next major effort will be introduce computerized guidelines on a more widespread basis, which will be challenging. However, the advent of managed care in the US has produced strong incentives to provide high quality care at low cost and our perspective is that only with better IS than exist today will this be possible without compromising quality. Such systems make feasible implementation of quality measurement, care improvement and cost reduction initiatives on a scale which could not previously be considered.

Computer Communication Networks↗
PubMedDate not supplied

Microvascular endothelial cells differ in their basal and tumour necrosis factor-alpha-regulated expression of adhesion molecules and cytokines.

We recently located a rare cytokeratin-positive (CK+) type of microvascular endothelial cell (MVEC) in the corpus luteum and aorta. Bovine corpus luteum MVEC are known to be involved in the cyclic accumulation of eosinophils and macrophages. Since leukocyte migration is specifically mediated by adhesion molecules and the release of cytokines, we compared the expression of these factors in basal and TNF-alpha-stimulated CK+ MVEC and in common cytokeratin-negative (CK-) MVEC in order to obtain an initial insight into the functional capacities of CK+ MVEC. CK- MVEC revealed significantly higher basal RANTES mRNA expression than CK+ MVEC, and TNF- alpha up-regulated RANTES mRNA in both types of MVEC. Only resting and stimulated CK- MVEC expressed granulocyte-macrophage colony-stimulating factor mRNA. Both MVEC types expressed monocyte colony-stimulating factor mRNA, but remained negative for eotaxin and interleukin (IL)-5 mRNA even after stimulation. Resting CK+ MVEC were positive for CD29, CD31, CD49a and CD49e, but expressed most of these antigens at a significantly lower density than did CK- MVEC. In contrast to CK- MVEC, CK+ MVEC failed to express CD49b or MHC class II. The activation of CK+ MVEC with TNF-alpha induced the expression of CD62P, but not of CD49b or MHC class II. In summary, phenotypically variable MVEC derived from the microvascular bed of one organ differ in their TNF-alpha-regulated expression of cytokine mRNA and adhesion molecules. Morphological heterogeneity is related to a particular specialisation of functional MVEC.

Animals↗