Rational role of amino acids in intestinal epithelial cells (Review)

There is much interest in precise functions of amino acids on mammalian growth and development. Some of amino acids play important roles in the control of gene expression by controlling the initiation phase of mRNA translation. The signal induced by leucine or arginine may stimulate cell growth. On the other hand, the other signal induced by glutamine may stimulate cellular proliferation and increase cell number, but inhibit the growth of cell size. However, there was no clear evidence that an individual amino acid specifically works as a signaling molecule. In our recent study, not only leucine, but also arginine is shown to activate the mTOR signaling pathway in rat intestinal epithelial cells. Furthermore, regarding L-Glutamine, an important amino acid that is required for culturing of numerous cell types, including rat intestinal epithelial cells, we have shown that it had an inhibitory effect on leucine- or arginine-induced activation of the mTOR signaling pathway. We have demonstrated that L-Glutamine inhibited the activation of p70 S6 kinase and phosphorylation of 4E-BP1 induced by arginine or leucine in rat intestinal epithelial cells. Based on these results, we are planning to confirm the effect of each amino acid including glutamine in an in vivo model using new born mice.     

Difference in the characteristics of subjective and objective sleepiness between narcolepsy and essential hypersomnia

The present study was conducted to investigate the difference in the characteristics of daytime sleepiness between narcolepsy and essential hypersomnia and to identify the relationship between the Epworth Sleepiness Scale (ESS) and the Multiple Sleep Latency Test (MSLT) in patients with these two disorders. Subjects consisted of 34 patients with essential hypersomnia (32.4 +/- 11.0 years old), 52 patients with narcolepsy (29.0 +/- 13.8 years old), and 45 control subjects (33.3 +/- 6.6 years old). The subjects completed the ESS and underwent MSLT following a regular sleep-wake schedule for over 2 weeks. The ESS scores were pathologically high and mean sleep latency on MSLT was short, not only in narcolepsy but also in essential hypersomnia. With respect to sleep latencies on each MSLT session, both essential hypersomnia and control subjects had the smallest value at 14:00, while narcolepsy lacked any statistical change at this time period. The correlation between ESS and mean sleep latency on MSLT was higher in essential hypersomnia than in narcolepsy, and the correlation was strongest for the session performed at 14:00. Based on the ESS and MSLT results, the severity of excessive daytime sleepiness was significantly milder in essential hypersomnia compared with that in narcolepsy. The results also indicate that diurnal variation of sleepiness was maintained, and the correlation between subjective and objective sleepiness was relatively maintained in essential hypersomnia compared to narcolepsy. It is suggested that the mild disease severity of essential hypersomnia contributed to the formation of these characteristics.     

Radiofrequency ablation of metastatic mediastinal lymph nodes during cooling and temperature monitoring of the tracheal mucosa to prevent thermal tracheal damage: initial experience

Institutional review board approval and patient informed consent were obtained. Radiofrequency ablation in a total of 10 sessions was performed for each mediastinal lymph node metastasis from esophageal cancer that had a mean largest diameter of 2.2 cm +/- 0.6 (standard deviation) in seven male patients (mean age, 59 years). During ablation, cooling and temperature of the tracheal mucosa were monitored in the proper position in eight of the 10 sessions; in the other two sessions, monitoring was not done because of tracheal stenosis (perforation resulted). Three of the four lymph nodes that were 2.0 cm or smaller in largest diameter showed no evidence of local progression for at least 1 year since ablation; all three of the nodes greater than 2.0 cm in largest diameter progressed within 6 months. The 1-year survival rate was 60%; the median survival time was 13 months. Radiofrequency ablation may be effective for local control of small metastatic mediastinal lymph nodes, and cooling and temperature monitoring of the tracheal mucosa in the proper position may prevent thermal tracheal damage.     

Retroperitoneoscopic live donor nephrectomy: extended experience in a single center

INTRODUCTION: Retroperitoneoscopic live donor nephrectomy (RPLDN) was performed because it is considered to be less invasive than open live donor-nephrectomy (OLDN) or transperitoneal laparoscopic live donor nephrectomy. PATIENTS AND METHODS: Between July 2001 and May 2003, 118 consecutive live donor kidney grafts were procured using RPLDN or OLDN. The patients who underwent RPLDN were divided into 2 groups: an initial group 1 (n = 38) and a subsequent group 2 (n = 48).Thirty-two patients who underwent OLDN during the same period were used as controls (group 3). The patients were placed in the lateral position. Three retroperitoneoscopic ports were inserted. The kidneys were retrieved through a 5-cm flank incision just below the 11th rib in group 1. In group 2, a 5-cm Pfannenstiel incision was used to extract the kidney. RESULTS: The operative time was 307 +/- 88 minutes, 245 +/- 42 minutes, and 215 +/- 70 minutes in groups 1, 2, and 3, respectively (group 1 vs group 2 or 3, P < .01). The mean postoperative pentazocine (painkiller) requirements were 12 mg, 4.4 mg, and 22 mg in groups 1, 2, and 3, respectively (group 2 vs group 1 or 3, P < .01). The hospital stay was 6.6 +/- 1.6, 4.9 +/- 0.7, and 7.0 +/- 0.1 days in groups 1, 2, and 3, respectively (group 2 vs group 1 or 3, P < .01). There were no serious complication, such as massive bleeding or bowel injury. CONCLUSIONS: RPLDN may be safer and less invasive than open donor nephrectomy.     

Blockade of TGF-beta action ameliorates renal dysfunction and histologic progression in anti-GBM nephritis

BACKGROUND: We tested whether the entire soluble extracellular domain of the human transforming growth factor-beta (TGF-beta) type II receptor, fused to the Fc portion of human immunoglobulin G (IgG1) (Tbeta-ExR) and expressed in skeletal muscles by adenovirus-mediated gene transfer (AdTbeta-ExR), can ameliorate renal dysfunction and histologic progression in a rat experimental anti-glomerular basement membrane (GBM) nephritis. METHODS: Anti-GBM nephritis was induced in Wistar Kyoto rats by an intravenous injection of anti-rat glomerular basement membrane (GBM) sera. At day 1 (24 hours after induction), AdTbeta-ExR (1 x 109 pfu/mL) was injected into the femoral muscle in the treatment group, and an adenovirus vector-expressing bacterial beta-galactosidase (AdLacZ) was injected into the control group. Then, clinical and histologic changes were examined for 3 weeks after the induction of anti-GBM nephritis. RESULTS: Tbeta-ExR was detected in the serum at day 7, but the serum concentration of Tbeta-ExR had decreased below the detectable level by day 14. Although blood pressure and the degree of proteinuria were similar in both groups, the deterioration of renal function was significantly blunted in the treatment group. Crescent formation and interstitial fibrosis were also ameliorated in the treatment group. These histologic improvements were accompanied by the decreased interstitial infiltration of macrophages and the decreased alpha-smooth muscle actin (alpha-SMA)-positive cells in the glomeruli and the interstitium. CONCLUSION: This study demonstrated for the first time that the blockade of TGF-beta action by AdTbeta-ExR in the early stage of anti-GBM nephritis ameliorates the clinical and histologic progression. In addition, this study shed light on the development of a specific gene therapy for human crescentic glomerulonephritis.     

Establishment of a prostatic small-cell carcinoma cell line (SO-MI)

BACKGROUND: Prostatic small-cell carcinoma is an extremely rare, highly aggressive disease. We established a cell line from this tumor. MATERIALS AND METHODS: Tumor tissue obtained from a 24-year-old Japanese man was used to establish the cell line. Cultured cells and tumors transplanted into nude mice were characterized by histologic, immunohistologic, immunocytologic, and molecular biologic methods. RESULTS: An immortal culture cell line (SO-MI) was successfully established. SO-MI cells adhered weakly to plastic surfaces in vitro, showing a 52- to 72-hr doubling time. SO-MI cells were heterotopically and orthotopically transplantable in nude mice. The cells were immunoreactive for NSE, chromogranin A, and NCAM, but not for ACTH, calcitonin, serotonin, gastrin, insulin, glucagons, LCA, EMA, PAP, PSA, androgen receptor, and p53. SO-MI cells secreted NSE in vitro and in vivo. SO-MI cells at passage 30 contained 50-59 chromosomes with a modal number of 55. PCR suggested that the p53 gene was deleted in SO-MI cells. RT-PCR detected no mRNA encoding androgen receptor in these cells. CONCLUSIONS: SO-MI cells retain the neuroendocrine nature of the original tumor, and should be useful in studying possible etiologies and new treatments.     

Y-chromosome microdeletion and phenotype in cytogenetically normal men with idiopathic azoospermia

OBJECTIVE: To determine the prevalence of microdeletions of the long arm of chromosome Y within the AZFa, AZFb, and AZFc subregions in patients with idiopathic azoospermia, and then correlate the microdeletions with clinical phenotypes to determine the most important subregion for screening. DESIGN: Controlled clinical study. SETTING: Male infertility clinic, Kobe University Hospital. PATIENT(S): Among 89 consecutive azoospermic patients, those whose infertility was related to known hereditary, endocrine, or obstructive causes or a cytogenetic abnormality were excluded; 54 remaining patients were studied using a polymerase chain reaction (PCR). Of these patients, 33 had Sertoli cell only syndrome, 10 had maturation arrest, and 11 had hypospermatogenesis. INTERVENTION(S): Blood and semen samples and testicular biopsies were obtained from all of the participants. MAIN OUTCOME MEASURE(S): We performed semen analysis, polymerase chain amplification of 28 DNA loci on the long arm of the Y chromosome involving the DAZ (deleted in azoospermia), and measured the plasma FSH, LH, testosterone, prolactin, and estradiol levels. RESULT(S): Microdeletions were detected in 14 of the 54 patients (nine with Sertoli cell only, three with maturation arrest, and two with hypospermatogenesis). Most microdeletions involved AZFb or AZFc. Patients with hypospermatogenesis or maturation arrest showed deletion only in AZFc. The DAZ gene was deleted in four patients with Sertoli cell only and one patient with maturation arrest. The RBM gene was deleted in two patients with Sertoli cell only who had particularly large deletions, but in no patients with arrest or hypospermatogenesis. CONCLUSION(S): Cytogenetically azoospermic patients should be examined for microdeletions before undertaking assisted reproduction. AZFc may be the most important subregion to screen. In addition, intact AZFa and AZFb subregions may be important for the presence of germ cells.