Immunoreactivity of glucose transporter 5 is located in epithelial cells of the choroid plexus and ependymal cells.

High fructose intake is associated with increased plasma triglyceride concentration, hepatic steatosis, impaired glucose tolerance, insulin resistance, and high blood pressure. In addition, increased fructose intake has recently been supposed to be a risk factor for dementia. However, direct effects of fructose on the brain function remain to be clarified. The localization of glucose transporter 5 (Glut5), a representative transporter of fructose, was immunohistochemically examined in the brains of humans, rats, and mice to clarify whether fructose was transported from the blood into the brain. Glut5 immunoreactivity was demonstrated to be located in the epithelial cells of the choroid plexus and the ependymal cells in the brains of humans and rats using commercial antibodies for Glut5. In addition, mRNA expression of mouse Glut5 was confirmed in the brains of mice. Immunohistochemical examination using a custom-made antibody against two regions of amino acid sequences of mouse Glut5 revealed that Glut5 immunoreactivity was also seen in the epithelial cells of the choroid plexus and the ependymal cells in the brains of mice. These findings show that Glut5 immunoreactivity is located in the epithelial cells of the choroid plexus and the ependymal cells, suggesting the possibility of the direct transportation of intravascular fructose into the brain parenchyma.

Transporters in the brain endothelial barrier.

The blood-brain barrier (BBB) not only impedes the influx of intravascular substances from blood to brain, but also promotes transport of substances from blood to brain or from brain to blood through several transport systems such as carrier-mediated transport, active efflux transport, and receptor-mediated transport systems. The multidrug resistance transporter P-glycoprotein (P-gp) is an ATP-dependent efflux pump and contributes to efflux of undesirable substances such as amyloid-beta:(Abeta) proteins from the brain into the blood as well as many drugs such as anti-cancer drugs. The inhibition of P-gp has favorable and unfavorable effects on living bodies. P-gp deficiency at the BBB induces the increase of Abeta:deposition in the brain of an Alzheimer disease mouse model. It is also known that the Abeta:deposition is inversely correlated with P-gp expression in the brains of elderly non-demented humans. However, the transient inhibition of P-gp by antidepressants enables medicines such as anti-cancer drugs to enter the brain. Concerning Abeta:clearance in the brain, the low-density lipoprotein receptor-related protein 1 (LRP1) is a major efflux transporter for Abeta, while the receptor for advanced glycation end products (RAGE) is a major influx transporter for Abeta:across the BBB. Dysfunction of the BBB with efflux and influx transporters may contribute to the pathogenesis of some degenerative neuronal disorders. This review will focus on several transporters and discuss how medicines pass the BBB to reach the brain parenchyma.

Short-term exposure to ethanol causes a differential response between nerve growth factor and brain-derived neurotrophic factor ligand/receptor systems in the mouse cerebellum.

Alcohol ingestion affects both neuropsychological and motor functions. We hypothesized that one of the key factors involved in such functions are neurotrophins and their receptors. We have therefore examined the effects of short-term ethanol exposure on the mRNA expression and protein levels of neurotrophin ligands and receptors in the cerebellum using real-time RT-PCR and Western blotting techniques. Male BALB/C mice were fed a liquid diet containing 5% (v/v) ethanol. The pair-fed control mice were fed an identical liquid diet except that sucrose was substituted isocalorically for ethanol. The cerebellum of mice exhibiting intoxication signs of stage 1 or 2 were used in the present study. We found that exposure to ethanol resulted in elevated levels of nerve growth factor (NGF) and TrkA mRNA expression but a decreased level of brain-derived neurotrophic factor (BDNF) mRNA expression. The expression of TrkB and p73 mRNA was unchanged. Changes in the level of these proteins were found to mirror these mRNA expression levels. We conclude that exposure to ethanol for a short period can cause a differential responsive in the various neurotrophin ligand/receptor systems. The functional consequences of these changes are unknown at present.

Possible role of REG Ialpha protein in ulcerative colitis and colitic cancer.

BACKGROUND AND AIMS: Although regenerating gene (REG) Ialpha protein may be involved in the inflammation and carcinogenesis in the gastrointestinal tract, its pathophysiological role in ulcerative colitis (UC) and the resulting colitic cancer remains unclear. We investigated expression of the REG Ialpha gene and its protein in UC and colitic cancer tissues. We examined whether cytokines are responsible for REG Ialpha gene expression and whether REG Ialpha protein has a trophic and/or an antiapoptotic effect on colon cancer cells. METHODS: Expression of REG Ialpha mRNA and its gene product in UC tissues was analysed by real time reverse transcription-polymerase chain reaction and immunohistochemistry, respectively. The effects of cytokines on REG Ialpha promoter activity were examined in LoVo cells by luciferase reporter assay. The effects of REG Ialpha protein on growth and H(2)O(2) induced apoptosis were examined in LoVo cells by MTT and TUNEL assays, respectively. RESULTS: REG Ialpha protein was strongly expressed in inflamed epithelium and in dysplasias and cancerous lesions in UC tissues. The level of REG Ialpha mRNA expression in UC tissues correlated significantly with severity of inflammation and disease duration. REG Ialpha promoter activity was enhanced by stimulation with interferon gamma or interleukin 6. REG Ialpha protein promoted cell growth and conferred resistance to H(2)O(2) induced apoptosis in LoVo cells. REG Ialpha protein promoted Akt phosphorylation and enhanced Bcl-xL and Bcl-2 expression in LoVo cells. CONCLUSIONS: The REG Ialpha gene is inducible by cytokines and its gene product may function as a mitogenic and/or an antiapoptotic factor in the UC-colitic cancer sequence.

Methylation of the oestrogen receptor gene in non-neoplastic epithelium as a marker of colorectal neoplasia risk in longstanding and extensive ulcerative colitis.

BACKGROUND: Surveillance colonoscopy is widely recommended in patients with longstanding and extensive ulcerative colitis (UC) in order to detect colorectal neoplasia at an early stage. However, it still remains questionable whether surveillance colonoscopy effectively enables early detection of UC associated neoplasia. There is a great need for sensitive markers to identify individuals at increased risk of neoplasia. The oestrogen receptor (OR) gene shows age related methylation in the colorectal epithelium and is methylated frequently in sporadic colorectal neoplasia, suggesting that OR methylation may predispose to colorectal neoplasia. AIM: To clarify whether analysis of methylation of the OR gene in non-neoplastic epithelium can contribute to prediction of increased neoplasia risk in UC patients. MATERIALS AND METHODS: A total of 165 non-neoplastic colorectal epithelia from 30 patients with longstanding and extensive UC, including 13 UC patients with neoplasia and 17 patients without, were evaluated. Methylation specific polymerase chain reaction was performed to determine the methylation status of the OR gene. RESULTS: Methylation of the OR gene was detected in 54 of 70 (77.1%) non-neoplastic colorectal epithelia in UC with neoplasia but in only 23 of 95 (24.2%) without neoplasia. Methylation of the OR gene was significantly more frequent in non-neoplastic epithelium from UC with neoplasia than in chronic colitic epithelium from UC without neoplasia. Furthermore, in UC with neoplasia, the OR gene was extensively methylated in non-neoplastic epithelia throughout the colorectum compared with those in UC without neoplasia. CONCLUSION: These results suggest that analysis of OR gene methylation may have potential as a useful marker for identifying individuals at increased risk of neoplasia among those with longstanding and extensive UC.

Development of colonic neoplasia in p53 deficient mice with experimental colitis induced by dextran sulphate sodium.

BACKGROUND: Several animal models for human ulcerative colitis (UC) associated neoplasia have been reported. However, most neoplasias developed in these models have morphological and genetic characteristics different from UC associated neoplasia. AIMS: To establish a new colitis associated neoplasia model in p53 deficient mice by treatment with dextran sulphate sodium (DSS). METHODS: DSS colitis was induced in homozygous p53 deficient mice (p53(-/-)-DSS), heterozygous p53 deficient mice (p53(+/-)-DSS) and wild-type mice (p53+/+-DSS) by treatment with 4% DSS. Numbers of developed neoplasias were compared among the experimental groups, and macroscopic and microscopic features of the neoplasias were analysed. Furthermore, K-ras mutation and beta-catenin expression were assessed. RESULTS: p53(-/-)-DSS mice showed 100% incidence of neoplasias whereas the incidences in p53(+/-)-DSS and p53+/+-DSS mice were 46.2% and 13.3%, respectively. No neoplasias were observed in the control groups. The mean numbers of total neoplasias per mouse were 5.0 (p53(-/-)-DSS), 0.62 (p53(+/-)-DSS), and 0.2 (p53+/+-DSS). The number of neoplasias per mouse in the p53(-/-)-DSS group was significantly higher than that in the other DSS groups. The incidences of superficial type neoplasias were 91.7% in p53(-/-)-DSS mice, 75.0% in p53(+/-)-DSS mice, and 33.3% in p53+/+-DSS mice. The K-ras mutation was not detected in any of the neoplasias tested. Translocation of beta-catenin from the cell membrane to the cytoplasm or nucleus was observed in 19 of 23 (82.6%) neoplasias. CONCLUSIONS: The p53(-/-)-DSS mice is an excellent animal model of UC associated neoplasia because the morphological features and molecular genetics are similar to those of UC associated neoplasia. Therefore, this model will contribute to the analysis of tumorigenesis related to human UC associated neoplasia and the development of chemopreventive agents.

Dedifferentiation and decreased expression of adhesion molecules, E-cadherin and ZO-1, in colorectal cancer are closely related to liver metastasis.

Carcinoma cells with high metastatic potential often show a dedifferentiated phenotype at the primary site. In this study, a total of 48 cases (24 primary tumors of colorectal cancer (Pr-CRC) with liver metastasis, 24 without) were examined for E-cadherin and ZO-1 expression by immunohistochemical staining, and for their dedifferentiated phenotype. The expression levels of E-cadherin and ZO-1 were markedly decreased in the cancer cells of tumors with liver metastasis. Moreover, dedifferentiation of cancer cells, which was evaluated by the modified Gleason score, was also related to liver metastasis. However, none of the conventional clinicopathologic parameters of invasion, except lymph node metastasis, showed any relationship with liver metastasis. These results indicate that dedifferentiation and a decreased expression of E-cadherin and ZO-1 are closely related to liver metastasis.

Genetic analysis of a local recurrent tumor after colonic polypectomy.

After polypectomy, the cut end of the polyp is usually examined by light microscopy to assess the risk of recurrent cancer. Here, we report a recurrent tumor that appeared in the colon 6 years after polypectomy, although cancer cells were not observed in hematoxylin and eosin-stained sections of the cut end of the primary polyp. Retrospectively, the primary polyp and the recurrent tumor were analyzed for mutations of the p53 gene. We detected p53 mutations in the primary polyp, even in the cut end of the polyp. The same set of two p53 mutations was detected in the recurrent tumor. These observations indicate a common origin of the primary tumor and the recurrent tumor. We conclude that it is important to analyze p53 mutations in colonic polyps, especially when the cut end of the polyp is difficult to evaluate histologically, in order to predict recurrence.

Decreased expression of E-cadherin and Yamamoto-Kohama's mode of invasion highly correlates with lymph node metastasis in esophageal squamous cell carcinoma.

OBJECTIVES: A reduction in cell-cell adhesion in cancer cells is an essential step in the progression from localized malignancy to metastatic disease. E-Cadherin is an important component of cell-cell adhesion molecules and may be a crucial determinant of tumor invasion and metastasis. E-Cadherin expression is reported to be correlated with lymph node metastasis in esophageal squamous cell carcinoma (SCC). The objective of this experiment is to examine the factors that are associated with invasion and metastasis of esophageal SCC. METHODS: Forty-six cases of esophageal SCC were examined by immunohistochemical staining for E-cadherin. The relationship between E-cadherin-staining patterns, conventional clinicopathological parameters and Yamamoto-Kohama's (Y-K's) mode of invasion were examined. RESULTS: The expression of E-cadherin on the cell membrane was reduced or lost in some of the esophageal SCC. Lymph node metastasis was highly correlated with the expression pattern of E-cadherin (p = 0.0002) and also highly correlated with Y-K's mode of invasion (p = 0.0078). However, lymph node metastasis was not correlated with any conventional clinicopathological parameters for invasion. CONCLUSIONS: These results indicate that E-cadherin plays a crucial role in invasion and metastasis in esophageal SCC, and that Y-K's mode of invasion highly reflects the invasiveness and metastatic potentials of esophageal SCC cells. Therefore, examination of the expression of E-cadherin and Y-K's mode of invasion would be helpful in predicting lymph node metastasis in esophageal SCC.

Relationship between cyclooxygenase-2 expression and K-ras gene mutation in colorectal adenomas.

BACKGROUND AND AIMS: Cyclooxygenase (COX)-2 has a trophic effect on gastrointestinal epithelial cells and is associated with the progression of colorectal adenomas. Mutation of the K-ras gene is also associated with the progression of colorectal adenomas and has recently been suggested to play an important role in the induction of COX-2. In the present study, we investigated the relationship between COX-2 expression and K-ras mutation in colorectal adenomas. METHODS: Twenty-nine colorectal adenomas were obtained from specimens resected by the use of surgery or endoscopic mucosal resection and analyzed clinicopathologically. Immunohistochemistry was performed to analyze COX-2 expression in the adenoma specimens. The K-ras codon 12 mutations were detected by using the polymerase chain reaction-restriction fragment length polymorphism method. RESULTS: An increase of COX-2-positive cells in adenoma was observed in 11 (37.9%) lesions, 10 (90.9%) of which had a K-ras gene mutation, suggesting a significant correlation between COX-2 expression and K-ras gene mutation in colorectal adenomas. Morphologically, COX-2-positive adenomas (13.8 +/- 2.6 mm) were significantly larger than COX-2-negative ones (5.8 +/- 0.9 mm). In addition, the increase of COX-2-positive cells in the lesion was observed more frequently in tubulovillous (63.6%) than in tubular (36.4%) adenoma. CONCLUSIONS: Cycloxygenase-2 expression in colorectal adenoma cells is strongly correlated with K-ras gene mutation, suggesting that COX-2 and mutated K-ras are connectively associated with the progression of colorectal adenoma.

Analysis of K-ras codon 12 mutations and p53 overexpression in colorectal nodule-aggregating tumors.

BACKGROUND AND AIMS: Morphologically, colorectal nodule-aggregating tumors are quite different from polypoid-type colorectal tumors that develop via the adenoma-carcinoma sequence. Although polypoid-type colorectal tumors are well known to have a high incidence of K-ras gene mutation and p53 overexpression, colorectal nodule-aggregating tumors have not been examined in terms of genetic changes and clinicopathological features. In the present study, therefore, we analysed the clinicopathological features, genetic changes in K-ras codon 12, and p53 overexpression in colorectal nodule-aggregating tumors. METHODS: A total of 18 colorectal nodule-aggregating tumors were surgically resected and then analysed clinicopathologically. Immunohistochemistry and polymerase chain reaction-single stranded conformational polymorphism were performed to analyse p53 abnormalities in the tumors. K-ras codon 12 mutations were screened out by the polymerase chain reaction-restriction fragment length polymorphism method and analysed by fluorescence direct sequencing. RESULTS: p53 overexpression was observed in six lesions (33%). p53-overexpressing cells were observed in parts of carcinoma or adenoma showing high-grade atypia. Four of the 10 (40%) samples had a p53 gene mutation. Nine of the 18 (50%) samples had a K-ras codon 12 point mutation. In eight cases (89%), the mutations of the K-ras codon 12 were of the same type: GGT (glycine) to GTT (valine). CONCLUSIONS: The colorectal nodule-aggregating tumor has distinctive characteristics showing a morphological phenotype of the superficial-type tumors and genotype of the polypoid tumors in terms of K-ras gene mutation and p53 overexpression.

Prevention of lymphocyst formation following systematic lymphadenectomy.

BACKGROUND: The occurrence of pelvic lymphocysts is an important complication following systematic lymphadenectomy for gynecological malignancies. We employed a procedure to prevent vaginal shortening following radical hysterectomy and we examined whether this procedure could be effective in preventing pelvic lymphocyst formation. METHODS: We studied the incidence of lymphocysts in 190 patients with 84 cervical cancers, 74 endometrial cancers and 32 ovarian cancers, using computed tomographic examination at 3 and 6 months subsequent to the surgery. The surgery included radical hysterectomy and a procedure to prevent vaginal shortening (101), modified radical hysterectomy (79) and simple hysterectomy (7), with systematic lymphadenectomy. RESULTS: There was a significant difference in the incidence of pelvic lymphocysts between cervical cancer (4.8%) and ovarian cancer (18.8%). The postoperative incidence of lymphocyst formation in patients undergoing radical hysterectomy with the procedure to prevent vaginal shortening (5.9%) was significantly lower than in those who underwent modified radical hysterectomy (15.2%). CONCLUSION: Our procedure to prevent vaginal shortening could be effective in preventing not only the shortening of the vagina but also the occurrence of pelvic lymphocysts in patients undergoing radical hysterectomy with systematic lymphadenectomy for gynecological malignancies.

[Histopathological diagnosis in reflux esophagitis].

We reviewed the histopathological features for the diagnosis of reflux esophagitis and gastroesophageal reflux disease(GERD) including carcinogenesis of the esophagus. Histologically, the presence of capillary dilatation, elongation of papillary, hyperplasia of basal layer, inflammatory cells-infiltration, balloon cells in the epithelium, and ulceration were evaluated in GERD cases. Although, histopathological changes were not clear in endoscopic-negative GERD cases, immunohistochemical examination with cell cycle protein(PCNA, p21, and p27) revealed the same abnormalities with GERD cases. In Japan, the majority cases of GERD are evaluated in grade according to Los Angeles system, therefore the prevalence of Barrett's esophagus and cancer is very low. We hypothesize that esophageal squamous cell carcinoma arising from GERD different from Barrett's cancer sequence, and clinicopathological long-term follow up will be required to assess the carcinogenesis including gene analysis.

Isolation, identification and determination of a magenta subsidiary colour in food blue no. 1 (brilliant blue FCF).

A magenta subsidiary colour was isolated from commercial Food Blue No. 1 (B-1; Brilliant Blue FCF). The absorption maximum for this subsidiary colour at 580 nm is outside of the range of 614-628 nm found for other subsidiary colours and m,m-B-1. On the basis of MS and NMR analyses, the structure of the subsidiary colour was elucidated as the disodium salt of 2-[[4-[N-ethyl-N-(3-sulphophenylmethyl)amino]phenyl][4-oxo- 2,5-cyclohexadienylidene]methyl]benzenesulphonic acid. HPLC analyses revealed that 24 batches of commercial Food Blue No. 1 (three manufacturers) contain 0.1-0.8% (average: 0.5%) of the magenta subsidiary colour.

Characterization of the DNA-binding state of the rat uterine estrogen receptor by UV cross-linking.

Characterization of the DNA-binding state of the rat uterine estrogen receptor was examined by UV cross-linking using [32P]5-bromo-2'-deoxyuridine-substituted 25-base pair synthetic oligonucleotide containing a Xenopus vitellogenin A2 estrogen response element (BrdUVRE). After UV irradiation of the receptor-BrdUVRE complexes, they were analyzed by SDS-polyacrylamide gel electrophoresis. In the nuclear estradiol-, ICI164, 384- and 4-hydroxytamoxifen-receptor complexes, the bands corresponding to the mobility of the receptor homodimer were observed. In a molybdate stabilized soluble receptor, we observed the bands with the slower mobility than the receptor homodimers.

[Cerebrospinal fluid fistula following an operation of mediastinal schwannoma: a case report].

A 33-year-old man was operated for the mediastinal schwannoma. During the operation, the 9 th intercostal nerve was avulsed and revealed liquorrhea. Lyodura and fibrin glue was applied for sealing the site of dural defect. But post-operative course was not successful. So, we used the external cerebrospinal fluid drainage system. After this procedure, thoracic fluid from the chest tube was reduced and we could remove the chest tube in the 20th post operative day. This case indicates that in case of thoracotomy, it is difficult to expect easy closure of cerebrospinal fluid fistula under conservative therapy. Therefore it was considered that specific repair during the operation and spinal drainage in the post-operative early phase should be performed.