Effect of L-phenylalanine supplementation and a high-protein diet on pharmacokinetics of cefdinir in healthy volunteers: an exploratory study.

BACKGROUND: Upregulation of oligopeptide transport activity by dietary protein, certain dipeptides and amino acids has been reported in the rat intestine and a human intestinal cell line. OBJECTIVE: In this study, the pharmacokinetics of cefdinir were investigated after L-phenylalanine supplementation and a high-protein diet (HPD) in humans to explore changes in the activities of intestinal and renal oligopeptide transporters. METHODS: A normal-protein diet (NPD, 73.2 +/- 2.6 g/day), NPD + l-phenylalanine (7.5 g/day), or HPD (141.3 +/- 3.7 g/day) was given to six male healthy volunteers for 12 days followed by a single dose of cefdinir after an overnight fast in a randomized three-way crossover study with a 22-day washout. Blood and urine were collected over a 12-h period after administration of cefdinir. Concentrations of cefdinir in plasma and/or urine were measured by high-performance liquid chromatography. RESULTS: Plasma concentrations and urinary excretion of the drug did not change throughout the study. Physiological variables and laboratory values did not reveal any differences between the three periods except for serum and urinary nitrogen levels and serum triglyceride. DISCUSSION: A reason for the unchanged pharmacokinetics of cefdinir may be due to lower doses of L-phenylalanine and protein in humans than in animals when converting animal effective doses to humans. CONCLUSION: In humans, L-phenylalanine supplementation and HPD do not seem to upregulate intestinal and renal oligopeptide transport in the ranges of duration and dose examined.

Laparoscopy-assisted distal gastrectomy for early gastric cancer: experience with 111 consecutive patients.

BACKGROUND: Laparoscopy-assisted distal gastrectomy (LADG) is gaining wider acceptance for the treatment of early gastric cancer. However, firm evidence supporting its safety and usefulness is scant, and no study has compared the outcomes of various procedures for LADG. We examined the surgical outcomes of LADG performed using different methods for lymph node dissection. METHODS: Between September 1998 and January 2005, we performed LADG in 111 patients with early gastric cancer. In the 55 patients treated initially, group 2 lymph node dissection was performed through a small, 7-cm-long incision (minilaparotomy). In 43 of these patients, hand-assisted laparoscopic surgery (HALS) was done. In the 56 patients treated more recently, lymph node dissection was performed laparoscopically. In 31 of these patients, the celiac branches of the vagus nerve were preserved. Clinical outcomes of these procedures were compared. RESULTS: In the first 55 patients, HALS significantly shortened the operation time (277 vs 243 min, p < 0.05). In the latter 56 patients, LADG with preservation of the celiac branches of the vagus nerve was associated with a longer operation time (283 vs 228 min, p < 0.01) and higher blood loss (150 vs 92 g, p < 0.05) than with LADG without celiac branch preservation. There were no differences among the various operative procedures in postoperative course, including the length of the postoperative hospital stay or the rate of complications. CONCLUSIONS: LADG is a safe and technically feasible procedure for the treatment of early gastric cancer. Laparoscopic lymph node dissection provided a good visual field and was easier to perform and required less time when the celiac branches of the vagus nerve were not preserved, with no negative effect on outcome.

Alpha-Fetoprotein-producing esophageal adenocarcinoma: report of a case.

Alpha-fetoprotein (AFP)-producing esophageal tumors are extremely rare. We report herein the case of a 51-year-old man found to have an AFP-producing adenocarcinoma arising from esophageal proper mucosa. The patient presented for investigation of dysphagia, and esophagogram and endoscopy revealed a lesion about 2 cm in size with a depressed center surrounded by low nodular protrusions in the lower esophagus. The preoperative serum AFP concentration was elevated to 52.4 ng/ml. A subtotal esophagectomy was performed, and macroscopic examination of the resected specimen revealed a superficial protruding lesion. Histopathological studies showed a poorly differentiated adenocarcinoma with a single lymph node metastasis. The tumor had infiltrated the submucosal layer, but there was no evidence of lymphatic or venous invasion. Immunohistochemical study revealed tumor cells positive for AFP. There were no findings of Barrett's epithelium or any mucosal changes due to reflux esophagitis. An elevated AFP level 2 years after the operation led us to suspect tumor recurrence; however, diagnostic imaging studies showed no evidence of a recurrence or metastases. The serum AFP levels responded well to chemotherapy with transient decreased levels, but continued to rise until finally, 5 years after the operation, adenocarcinoma cells were detected in the pleural effusion. Thus, careful monitoring of the serum AFP levels at regular intervals could be a useful marker to indicate recurrence of esophageal carcinoma.