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D Kunkel

Publications and source records attributed to D Kunkel.

12 recordsLinked to original sources
PubMed2001

How alpha beta T cells deal with induced TCR alpha ablation.

On deletion of the gene encoding the constant region of the T cell antigen receptor (TCR)alpha chain in mature T cells by induced Cre-mediated recombination, the cells lose most of their TCR from the cell surface within 7--10 days, but minute amounts of surface-bound TCR beta chains are retained for long periods of time. In a situation in which cellular influx from the thymus is blocked, TCR-deficient naive T cells decay over time, the decay rates being faster for CD8(+) cells (t(1/2) approximately 16 days) than for CD4(+) cells (t(1/2) approximately 46 days). TCR(+) naïve cells are either maintained (CD8(+)) or decay more slowly (CD4(+); t(1/2) approximately 78 days.) Numbers of TCR-deficient memory T cells decline very slowly (CD8(+) cells; t(1/2) approximately 52 days) or not at all (CD4(+) cells), but at the population level, these cells fail to expand as their TCR(+) counterparts do. Together with earlier data on T cell maintenance in environments lacking appropriate major histocompatibility complex antigens, these data argue against the possibility that spontaneous ligand-independent signaling by the alpha beta TCR contributes significantly to T-cell homeostasis.

Animals↗
PubMed2000

Testing legal assumptions regarding the effects of dancer nudity and proximity to patron on erotic expression.

A field experiment was conducted in order to test the assumptions by the Supreme Court in Barnes v. Glen Theatre, Inc. (1991) and the Ninth Circuit Court of Appeals in Colacurcio v. City of Kent (1999) that government restrictions on dancer nudity and dancer-patron proximity do not affect the content of messages conveyed by erotic dancers. A field experiment was conducted in which dancer nudity (nude vs. partial clothing) and dancer-patron proximity (4 feet; 6 in.; 6 in. plus touch) were manipulated under controlled conditions in an adult night club. After male patrons viewed the dances, they completed questionnaires assessing affective states and reception of erotic, relational intimacy, and social messages. Contrary to the assumptions of the courts, the results showed that the content of messages conveyed by the dancers was significantly altered by restrictions placed on dancer nudity and dancer-patron proximity. These findings are interpreted in terms of social psychological responses to nudity and communication theories of nonverbal behavior. The legal implications of rejecting the assumptions made by the courts in light of the findings of this study are discussed. Finally, suggestions are made for future research.

Adult↗
PubMed1999

Characteristics of intestinal metaplasia in the gastric cardia.

OBJECTIVE: Intestinal metaplasia of the gastroesophageal junction is frequently grouped together with Barrett's esophagus. The area of the gastroesophageal junction is comprised of the distal esophagus and the gastric cardia. The aim of the present study was to assess whether intestinal metaplasia in the distal esophagus and gastric cardia represent two different entities with a different set of risk factors. METHODS: Patients presenting for elective upper endoscopy were enrolled into a prospective study. The presence of gastritis and intestinal metaplasia was evaluated in gastric biopsies taken from the antrum, corpus, and cardia. Barrett's esophagus was defined by the presence of any length of columnar mucosa above the gastroesophageal junction. RESULTS: Of 302 patients, 50 patients had intestinal metaplasia of the gastric cardia, 73 Barrett's esophagus, and 116 erosive esophagitis. Men were more prone than women to develop Barrett's esophagus or erosive esophagitis. Both conditions were also more common among whites than nonwhites. Smoking was particularly common among patients with Barrett's esophagus. Patients with cardiac intestinal metaplasia did not share these demographic characteristics. The prevalence of daily reflux symptoms, erosive esophagitis, and Barrett's esophagus was similar among patients both with and without cardiac intestinal metaplasia. However, atrophy and intestinal metaplasia of the gastric antrum and corpus were found more frequently among patients with than without cardiac intestinal metaplasia. CONCLUSIONS: Intestinal metaplasia of the gastric cardia is different from Barrett's esophagus. Although cardiac intestinal metaplasia is closely associated with signs of gastritis in other parts of the stomach, gastroesophageal reflux disease does not seem to be a risk factor. A diagnosis of Barrett's esophagus should not be made based on the presence of intestinal metaplasia within the cardiac portion of the gastroesophageal junction.

Barrett Esophagus↗
PubMed1993

[Primary melanoma of the esophagus].

The authors report 2 cases of primary melanoma of the esophagus, and describes the clinical, endoscopical, radiological and histological features from these exceptional tumors. Prognosis is very poor, despite various therapeutical possibilities.

Aged↗
PubMed1993

[Angiosarcoma of the aorta revealed by an intestinal metastasis].

We report a case of aortic endothelioma revealed by intestinal metastasis in a man who was admitted for severe anemia, left heart failure, and fatal ileo-mesenteric infarction. This is the 13th published case of aortic endothelioma, and the first case revealed by intestinal metastasis. It illustrates the value of the magnetic resonance imaging for the detection of an aortic tumor when intestinal angiosarcoma has been diagnosed. The surgical treatment could improve an otherwise very poor prognosis.

Aorta, Thoracic↗
PubMed1987

Primate neostriatal neurons containing tyrosine hydroxylase: immunohistochemical evidence.

We have detected, in monkey caudate nucleus and putamen, neuronal cell bodies containing tyrosine hydroxylase-like immunoreactivity, as revealed by peroxidase-antiperoxidase immunohistochemistry. Many of these cells are distributed in an outer rim of 1-2 mm throughout the anterior-posterior extent of the neostriatum near its borders with the corona radiata; others are embedded in the adjacent white matter, especially near the ventral putamen and nucleus accumbens. Light and electron microscopy indicate that they are small (8-12 micron), bipolar cells with large nuclei. Such neostriatal neurons, containing tyrosine hydroxylase-like immunoreactivity, number in the tens of thousands.

Animals↗