Point mutations of ornithine decarboxylase gene are an infrequent event in colorectal cancer but a missense mutation was found in a replication error positive patient with hMSH2 germline mutation

BACKGROUND: Ornithine decarboxylase (ODC; EC 4.1.1.17) is the first rate-limiting enzyme in the biosynthesis of polyamines. ODC protein has a characteristic amino acid sequence, the PEST sequence, which is related to the enzyme's rapid degradation. ODC cDNA prepared from human hepatoma tissues has been reported to show nonsense or missense mutations. METHODS: We examined somatic mutations of ODC cDNA by RT-PCR-SSCP analysis and mRNA expressions by RT-PCR in 50 colorectal cancer tissues to investigate the involvement of ODC gene alterations in colorectal cancers. RESULTS: Increased expression of the ODC gene was observed in 36 cases (86%) out of the 42 examined by RT-PCR. In one case, a missense mutation was found in the cancer tissue but not in normal mucosa. The missense mutation from Asp to Asn at codon 424, in the PEST region, possibly stabilizes the ODC protein. In colorectal cancer, replication error and a germline mutation in hMSH2 gene were observed. CONCLUSIONS: The missense mutation at codon 424 is speculated to be a cause of stabilization and a passenger mutation owing to the mutator phenotype. Since only one of 50 colorectal cancers exhibited a missense mutation of the ODC gene, mutations in ODC gene are not frequent in colorectal cancer. The increased expression of the ODC gene was noted in 86% of colorectal cancer tissues by RT-PCR, however, it was not due to point mutations in ODC coding exons.      

The 1.5 GHz Electromagnetic Near-field Used for Cellular Phones Does Not Promote Rat Liver Carcinogenesis in a Medium-term Liver Bioassay

We have recently established that local exposure to a 929.2 MHz electromagnetic near-field, used for cellular phones, does not promote rat liver carcinogenesis in a medium-term bioassay system. In the present study, a 1.439 GHz electromagnetic near-field (EMF), another microwave band employed for cellular phones in Japan, was similarly investigated. Time division multiple access (TDMA) signals for the Personal Digital Cellular (PDC) Japanese cellular telephone standard system were directed to rats through a quarter-wavelength monopole antenna. Numerical dosimetry showed that the peak SARs within the liver were 1.91–0.937 W/kg, while the whole-body average specific absorption rates (SARs) were 0.680–0.453 W/kg, when the time-averaged antenna radiation power was 0.33 W. Exposure was for 90 min a day, 5 days a week, over 6 weeks, to male F344 rats given a single dose of diethylnitrosamine (200 mg/kg, i.p.) 2 weeks previously. At week 3, all rats were subjected to a two-thirds partial hepatectomy. At week 8, the experiment was terminated and the animals were killed. Carcinogenic potential was scored by comparing the numbers and areas of the induced glutathione S-transferase placental form (GST-P)-positive foci in the livers of exposed (48) and sham-exposed rats (48). Despite increased serum levels of corticosterone, adrenocorticotropic hormone (ACTH) and melatonin, the numbers and the areas of GST-P-positive foci were not significantly altered by the exposure. These findings clearly indicated that local body exposure to a 1.439 GHz EMF, as in the case of a 929.2 MHz field, has no promoting effect on rat liver carcinogenesis in the present model.     

Entire septal patch technique for postinfarction ventricular septal rupture

Postinfarction ventricular septal rupture is still a surgically challenging situation with high operative mortality. We report a case of ventricular septal rupture in a 75-year-old woman successfully treated with our newly devised technique, in which a pliable large septal path is fixed with transmural sutures placed in posterior left ventricular free wall and anterior ventriculotomy closing sutures, thus covering the septal wall almost entirely. Our method may simplify the operation and reduce the risk of residual leakage.     

Serial changes in N-isopropyl-p[125I]-iodoamphetamine in mouse lung observed with a confocal laser scanning microscope

Serial changes in N-isopropyl-p[125I]-iodoamphetamine (125I-IMP) in mouse lungs were observed with a confocal laser scanning microscope. Male mice were intravenously injected with 125I-IMP and subjected to autoradiographic procedures 20 minutes, and 3 and 24 hours after injection. Differential interference contrast (DIC) images and confocal images were obtained with a confocal laser scanning microscope, and superimposed images were evaluated. Large numbers of silver grains were observed in the interstitium, bronchioles, and alveolar sacs 20 minutes after the injection, and lamellar distribution of the grains was observed on the ciliary surface. The numbers of silver grains in the interstitium and bronchioles had decreased 3 hours after the injection of 125I-IMP, but the numbers of silver grains in the alveolar spaces had not. Although small numbers of silver grains remained in both the bronchioles and alveolar sacs 24 hours after the injection, most of them had washed out. Confocal laser scanning microscopy is considered to be a useful procedure for studying the distribution of radioisotopes by microautoradiography, because it allows clear autoradiographs to be obtained in which tissues and silver grains are perfectly matched and all silver grains are in focus.     

Effect of plaunotol on bacterial translocation in the rat small intestine

BACKGROUND AND AIMS: Bacterial translocation is precipitated by an increase in bacteria or endotoxin, depression of the membrane barrier, and an increase in mucosal permeability. Plaunotol is a mucosal protective agent, and observed to have a strong suppressive effect on superoxide production. In this study, the effect of plaunotol on bacterial translocation was examined using the model of ischemia and reperfusion. METHOD: Male Sprague Dawley rats were used to create the following model for evaluation of bacterial translocation: (i) the control group; (ii) the preventive dose group (plaunotol 30 mg/kg/day one week before surgery); (iii) the therapeutic dose group (plaunotol 30 mg/kg/day one week after surgery); and (iv) the full dose group (plaunotol 30 mg/kg/day one week before surgery and one week after surgery). Bacterial translocation was assessed as the blood concentration of the endotoxin. RESULTS: In the control group, the endotoxin increased significantly 3 days postsurgery (13.7+/-5.6 pg/ml) compared with before surgery (1.1+/-0.1 pg/ml). In the preventive and full-dose groups, the erndotoxin decreased significantly 3 days postsurgery (4.4+/-2.8 pg/ml, 5.7+/-2.7 pg/ml, respectively) compared with that of the control group. CONCLUSION: Plaunotol in the preventive and full-dose groups decreased the endotoxin. This suggests that plaunotol is one of the protectors for bacterial translocation.     

A case of hemorrhagic cyst of the pancreas resembling the cystic endometriosis

A 47-year-old Japanese woman with a history of epigastric pain and a recent episode of acute pancreatitis (back pain, nausea, and vomiting) and anemia was found to have a pancreatic cyst of the tail on CT-scan and ultrasonography. Especially, ultrasonography revealed the papillary solid lesion in the cyst. With the tentative diagnosis of a cystic neoplasm, distal pancreatectomy was performed. Histological examination of sections showed massive hemorrhage, surrounded fibrous connective tissue, and numerous macrophages with hemosiderin deposits; these histological findings resembled cystic endometriosis. The clinicopathological features and pathogenesis of the pancreatic endometrial cyst are discussed.     

Endoloop ligation technique for prolapsed pedunculated submucous uterine myoma: utility and reliability

Purpose

We use a non-surgical endoloop snare technique to remove prolapsed pedunculated submucous uterine myomas under the concept that ligating the pedicle causes tumor necrosis and natural elimination of the tumor. We evaluated our method on the basis of clinical outcomes.

Methods

For pertinent clinical data, we reviewed the hospital records of 11 patients treated by our new method between July 2009 and 2010 and followed up for 22–31 months.

Results

Patients’ mean age was 40.9 years, and the mean hemoglobin level was 10.6 g/dl. None required urgent hospitalization, blood transfusion, or laparotomy. The tumors were eliminated naturally or removed by cutting necrotic pedicle within 4–11 days. One patient required a second endoloop application. Another one patient required follow-up surgery for a second submucous myoma, adenomyosis, and persistent hypermenorrhea.

Conclusions

Endoloop ligation is feasible for eliminating prolapsed pedunculated submucous myoma. It is simple and safe and can be performed in the outpatient setting.     

Determination of paroxetine in human saliva by reversed-phase high-performance liquid chromatography with UV detection.

A rapid and sensitive high-performance liquid chromatographic method was validated and described for determination of paroxetine in human saliva. Following liquid-liquid extraction of the drug and an internal standard (dibucaine), chromatographic separation was accomplished using a C18 analytical column with a mobile phase consisting of 0.05 mol/L sodium phosphate buffer, pH 5.0, and acetonitrile (A 30:70, v/v; B 60:40, v/v). Paroxetine and the internal standard were detected by ultraviolet absorbance at 205 nm. The average recoveries of the drug and internal standard were 92.5% and 89%, respectively. The lower limits of detection and quantification were 1 and 4 ng/ml, respectively, and the calibration curve was linear over a concentration range of 4 ng/ml. The saliva level of paroxetine in patients with depression taking 10 to 40 mg/day of the drug was significantly correlated with the plasma level of paroxetine in each patient (r = 0.617, P < 0.004, n = 19). These data indicate that the saliva level of paroxetine could be a useful marker to predict the plasma level of the drug.