The hormonal regulation of pyloric sphincteric function

A B S T R A C T The purpose of this study was to evaluate the hormonal control of pyloric sphincter function. Studies were performed on both pyloric circular muscle, in vitro, and the human pylorus, in vivo. Full dose-response curves to gastrin I, cholecystokinin, and secretin were constructed for the pyloric muscle of the opossum studied at its length of optimal tension development, Lo. Both cholecystokinin and secretin were potent agonists on the muscle but gastrin I gave no increase in muscle tension. The combination of cholecystokinin and secretin was additive at submaximal concentrations but potentiation of the maximal responses was not observed. Gastrin I produced a surmountable, competitive-like antagonism to the effect of cholecystokinin on the pyloric muscle. The octapeptide of cholecystokinin was a more potent agonist than the whole molecule of cholecystokinin on the pyloric muscle. In man, the pyloric pressure rose significantly during intravenous infusion of either cholecystokinin or secretin. The combination of maximal doses of both hormones did not show signficant potentiation. Gastrin I did not significantly increase pyloric pressure but did antagonize the pyloric response to duodenal acidification. These studies suggest that: (a) Both secretin and cholecystokinin augment pyloric sphincter pressure while gastrin I is an antagonist inhibiting their effects. (b) The hormonal responses of pyloric sphincter circular muscle, in vitro, can be correlated with human sphincter function, in vivo

Disease signatures are robust across tissues and experiments

Meta-analyses combining gene expression microarray experiments offer new insights into the molecular pathophysiology of disease not evident from individual experiments. Although the established technical reproducibility of microarrays serves as a basis for meta-analysis, pathophysiological reproducibility across experiments is not well established. In this study, we carried out a large-scale analysis of disease-associated experiments obtained from NCBI GEO, and evaluated their concordance across a broad range of diseases and tissue types. On evaluating 429 experiments, representing 238 diseases and 122 tissues from 8435 microarrays, we find evidence for a general, pathophysiological concordance between experiments measuring the same disease condition. Furthermore, we find that the molecular signature of disease across tissues is overall more prominent than the signature of tissue expression across diseases. The results offer new insight into the quality of public microarray data using pathophysiological metrics, and support new directions in meta-analysis that include characterization of the commonalities of disease irrespective of tissue, as well as the creation of multi-tissue systems models of disease pathology using public data

Atropselective syntheses of (-) and (+) rugulotrosin A utilizing point-to-axial chirality transfer

Chiral, dimeric natural products containing complex structures and interesting biological properties have inspired chemists and biologists for decades. A seven-step total synthesis of the axially chiral, dimeric tetrahydroxanthone natural product rugulotrosin A is described. The synthesis employs a one-pot Suzuki coupling/dimerization to generate the requisite 2,2'-biaryl linkage. Highly selective point-to-axial chirality transfer was achieved using palladium catalysis with achiral phosphine ligands. Single X-ray crystal diffraction data were obtained to confirm both the atropisomeric configuration and absolute stereochemistry of rugulotrosin A. Computational studies are described to rationalize the atropselectivity observed in the key dimerization step. Comparison of the crude fungal extract with synthetic rugulotrosin A and its atropisomer verified that nature generates a single atropisomer of the natural product.P50 GM067041 - NIGMS NIH HHS; R01 GM099920 - NIGMS NIH HHS; GM-067041 - NIGMS NIH HHS; GM-099920 - NIGMS NIH HH

Current potential and limitations of molecular diagnostic methods in head and neck cancer

Item does not contain fulltextTraditional diagnostic methods such as clinical assessment, histopathological examination and imaging techniques are limited in their capacity to provide information on prognosis and treatment choice of head and neck cancer. In recent years, molecular techniques have been developed that enabled us to get more insight into the molecular biological cellular pathways underlying tumor progression and metastasis. Correlation of these molecular changes with clinical events has been explored. However, consistently useful markers have not been identified yet, although many promising developments are in progress. It may be expected that in the near future, molecular markers will be useful for clinical purposes. In this paper, an overview will be given of the several molecular techniques that may have potential to be introduced in clinical practice in the management of head and neck squamous cell carcinoma.1 juni 201

Documents from Carter\u27s Contemplated Use of Section 3 (1978)

Forms drafted in response to the possibility that President Carter might undergo hemorrhoid surgery under anesthesia. Handwritten notes at the end of the document relate to the draft language and the procedures for notifying congressional leaders of the transfer of powers. The author of the notes is unclear.https://ir.lawnet.fordham.edu/twentyfifth_amendment_executive_materials/1001/thumbnail.jp