Direct evidence of edge-to-face CH/π interaction for PAR-1 thrombin receptor activation.

Heptapeptide SFLLRNP is a receptor-tethered ligand of protease-activated receptor 1 (PAR-1), and its Phe at position 2 is essential for the aggregation of human platelets. To validate the structural elements of the Phe-phenyl group in receptor activation, we have synthesized a complete set of S/Phe/LLRNP peptides comprising different series of fluorophenylalanine isomers (Fn)Phe, where n = 1, 2, 3, and 5. Phe-2-phenyl was strongly suggested to be involved in the edge-to-face CH/π interaction with the receptor aromatic group. In the present study, to prove this receptor interaction definitively, we synthesized another series of peptide analogs containing (F4)Phe-isomers, with the phenyl group of each isomer possessing only one hydrogen atom at the ortho, meta, or para position. When the peptides were assayed for their platelet aggregation activity, S/(2,3,4,6-F4)Phe/LLRNP and S/(2,3,4,5-F4)Phe/LLRNP exhibited noticeable activity (34% and 6% intensities of the native peptide, respectively), whereas S/(2,3,5,6-F4)Phe/LLRNP was completely inactive. The results indicated that, at the ortho and meta positions but not at the para position, benzene-hydrogen atoms are required for the CH/π interaction to activate the receptor. The results provided a decisive evidence of the molecular recognition property of Phe, the phenyl benzene-hydrogen atom of which participates directly in the interaction with the receptor aromatic π plane.

[A case of squamous cell lung carcinoma with gastric metastasis diagnosed by gastroendoscopic biopsy].

A 59-year-old man was referred to our hospital due to of a right pulmonary hilar mass shadow found on a chest X-ray film in October 2008. Bronchoscopy and transbronchial biopsy at that time revealed squamous cell carcinoma. The clinical stage was IIIB (T4N2M0). He was readmitted 2 months later because of appetite loss and severe anemia. An abdominal CT scan showed thickening of the stomach wall. Gastroendoscopy showed a submucosal tumor with central depression in the middle body of the stomach. We histologically confirmed that the gastric lesion was metastasis from the squamous cell lung carcinoma. Here we report a rare case of squamous cell lung carcinoma with gastric metastasis diagnosed by gastroendoscopic biopsy while the patient was alive.

Effectiveness of an outpatient preoperative care bundle in preventing postoperative pneumonia among esophageal cancer patients.

BACKGROUND: This historical case-control study examined the effectiveness of an outpatient preoperative care bundle on the incidence of postoperative pneumonia among patients with esophageal cancer. METHODS: We implemented a preoperative care bundle that comprised 7 care procedures that previous studies had suggested to be effective for decreasing postoperative respiratory complications, infections, postoperative hospital stay, and mortality. The care bundle group included patients who underwent surgery after the care bundle was implemented, whereas the control group included those who underwent surgery before its implementation. RESULTS: The incidence of postoperative pneumonia was 3.8% in the care bundle group (1/26) and 22.4% in the control group (48/214). A logistic regression model showed that implementation of the care bundle had a significant effect on prevention of postoperative pneumonia (odds ratio, 0.16; 95% confidence interval: 0.01-0.94) after controlling the following confounding factors: sex, blood urea nitrogen, amount of blood loss, recurrent laryngeal nerve palsy, and preoperative hospital stay. CONCLUSION: Implementation of the procedures of the preoperative care bundle was shown to be effective for preventing postoperative pneumonia in patients with esophageal cancer.