A novel water-in-oil emulsion with a lecithin-modified bentonite prevents skin damage from urban dust and cedar pollen.

OBJECTIVE: Particulate matter (PM), such as air pollutants and pollens, are known to cause skin ageing through skin inflammation. It is important to develop formulations which protect the skin from PM. We previously developed a conventional water-in-oil emulsion with a synthetic surfactant, distearyldimonium chloride, modified bentonite (C-W/O), which protects skin from allergens. In the present study, we developed a novel water-in-oil emulsion with a natural surfactant, lecithin, modified bentonite (N-W/O). METHODS: The microarray analysis was performed using total RNA extracted from a reconstructed human epidermis (RHE) stimulated with urban aerosols or cedar pollen for 6 h in order to develop an epidermal inflammation model by PM for the evaluation of topical formulations. We then compared the efficacy of N-W/O and C-W/O to prevent epidermal degradation. Tissues and culture media were collected 24 h after the urban aerosol or cedar pollen stimulation for a histological assay, and the quantification of MMP1 and IL-8 secretion. RESULTS: The expression levels of proinflammatory cytokines and chemokines, such as IL1A and CXCL8, and matrix metalloproteinases, including MMP1, MMP3 and MMP9, were significantly up-regulated by the PM stimulation. As a result of ranking based on the pathway enrichment analysis, oxidative stress-related pathways, such as MAPK-mediated signalling, HIF-1 signalling, IL-1 signalling and ROS-induced cellular signalling, were ranked high in the urban dust- and cedar pollen-treated groups. A thickened stratum corneum, thinned vital layer and cleaved E-cadherin were observed by haematoxylin and eosin staining and immunohistochemical staining of E-cadherin in the PM treated groups. The secretion of MMP1 and IL-8 into the media was significantly increased by the PM stimulation. N-W/O prevented the degradation of epidermal integrity and secretion of inflammatory proteins more effectively than C-W/O. CONCLUSION: The present results showed that N-W/O made using natural surfactant is useful at protecting skin from PM, such as urban aerosols and cedar pollen.

OBJECTIF: Les particules en suspensions (PM), telles que les polluants atmosphériques et les pollens, sont connues comme des causes de vieillissement de la peau par inflammation cutanée. Il est essentiel de mettre au point des formules qui protègent la peau contre ces particules. Par le passé, nous avons mis au point une émulsion eau-dans-huile classique composée d'un tensioactif synthétique, de distearyldimonium chloride et de bentonites modifiées (E/H-C), qui protège la peau contre les allergènes. Dans la présente étude, nous avons conçu une nouvelle émulsion eau-dans-huile composée d'un tensioactif naturel, de lécithine et de bentonites modifiées (N-E/H). MÉTHODES: L'analyse des microréseaux a été réalisée à l'aide de l'ARN total extrait d'un épiderme humain reconstitué (EHR) stimulé par les aérosols urbains ou le pollen de cèdre pendant 6 h afin de mettre au point un modèle d'inflammation de l'épiderme par les particules en suspensions en vue de l'évaluation des formulations topiques. Nous avons ensuite comparé l'efficacité de la N-E/H et de l'E/H-C dans le but d'éviter la dégradation de la peau. Les milieux de culture tissulaire ont été collectés 24 h après stimulation par l'aérosol urbain ou par du pollen de cèdre pour un dosage histologique et une quantification de MMP-1 et des sécrétions de l'IL-8. RÉSULTATS: Les niveaux d'expression des cytokines pro-inflammatoires et des chimiokines, à l'instar de l'IL1A et du CXCL8, ainsi que des métalloprotéinases matricielles, notamment les MMP1, les MMP3 et les MMP9, étaient essentiellement régulés positivement par la stimulation des particules en suspensions. En raison du classement basé sur l'analyse d'enrichissement des voies, le stress oxydatif, telles que la signalisation médiée par MAPK, la signalisation HIF-1, la signalisation IL-1 et la signalisation cellulaire induite par les ROS ont été classés en tête pour les groupes traités par la poussière urbaine et par le pollen-de cèdre. Un stratum corneum épaissie, une couche vitale fine et une clivée d'E-cadhérine ont été observées par coloration à l'hématoxyline-éosine et par coloration immunohistochimique de l'E-cadhérine dans les groupes traités aux particules en suspensions. La sécrétion de MMP1 et de l'IL-8 dans les milieux a augmenté de façon significative par stimulation des particules en suspensions. La N-E/H a permis d'éviter une dégradation de l'intégrité de la peau et la sécrétion de protéines inflammatoires de manière plus efficace que l'E/H-C. CONCLUSION: Les résultats actuels ont révélé que la N-E/H produite grâce à l'utilisation d'un tensioactif naturel est utile pour la protection de la peau contre les particules en suspensions telles que les aérosols urbains et le pollen de cèdre.

Lung Sound Analysis Is Useful for Monitoring Therapy in Patients With Bronchial Asthma.

BACKGROUND AND OBJECTIVE: Lung sound analysis (LSA) has been reported to be useful for predicting airway obstruction and inflammation in patients with bronchial asthma. Objectives: We examined whether the exhalation-to-inhalation sound pressure ratio in the middle frequency range (200-400 Hz) (E/I MF) is useful for monitoring therapy in patients with asthma. METHODS: The study population comprised 84 patients with mild to moderate asthma whose LSA data were available before and after 1 year of daily treatment with (budesonide 800 µg). We analyzed whether the E/I MF before and after treatment was associated with the fractional exhaled nitric oxide (FeNO) level, sputum eosinophil percentage, respiratory function, and airway hyperresponsiveness. RESULTS: Prior to treatment with budesonide, the E/I MF was significantly correlated with respiratory function, airway hyperresponsiveness, FeNO, and sputum eosinophil percentage. The cutoff values for the E/I MF to detect the abnormalities of respiratory function, FeNO, and sputum eosinophil percentage were 0.367, 0.358, and 0.363, respectively. With respect to the reference value, the E/I MF improved significantly in patients whose respiratory function and FeNO benefited from therapy with budesonide compared with patients whose respiratory function did not benefit from budesonide (odds ratios of 6.39 and 4.78, respectively). According to the multivariate analysis, patients whose E/I MF did not improve had a longer history of smoking (P=.038), poorer posttreatment respiratory function (P=.028), and higher posttreatment FeNO (P=.0095). CONCLUSIONS: Similar to respiratory function and FeNO, E/I MF based on LSA is a useful indicator for monitoring the efficacy of therapy in asthmatic patients.

Impact of UCP1 and ß3AR gene polymorphisms on age-related changes in brown adipose tissue and adiposity in humans.

BACKGROUND: Brown adipose tissue (BAT) is involved in the regulation of whole-body energy expenditure and adiposity. The activity and prevalence of BAT decrease with age in humans. OBJECTIVE: To examine the effects of single nucleotide polymorphisms of the genes for uncoupling protein 1 (UCP1) and ß3-adrenergic receptor (ß3AR), key molecules of BAT thermogenesis, on age-related decline of BAT activity and accumulation of body fat in humans. METHODS: One hundred ninety-nine healthy volunteers (20-72 years old (y.o.)) underwent fluorodeoxyglucose-positron emission tomography (FDG-PET) and computed tomography (CT) after 2-h cold exposure to assess BAT activity. The visceral and subcutaneous fat areas at the abdominal level were estimated from the CT images. They were genotyped for -3826 A/G polymorphism of the UCP1 gene and 64 Trp/Arg mutation of the ß3AR gene. RESULTS: BAT was detected in 88 subjects out of 199 (44%), more in younger (30 y.o., 55%) than older subjects (>40 y.o., 15%). BAT prevalence of older subjects tended to be lower in the UCP1 G/G group than the A allele group (A/A and A/G), and also in the ß3AR Arg allele group (Trp/Arg and Arg/Arg) than the Trp/Trp group. When compared subjects who had two or more base substitutions on the two genes (the 2-4 allele group) with those who had less than two base substitutions (the 0-1 allele group), BAT prevalence was comparable in younger subjects (62% vs 50%) but lower in older subjects (0% vs 24%, P<0.05). Visceral fat area of the 2-4 allele group was higher than that of the 0-1 allele group (P<0.05) in older subjects, but not in younger subjects. CONCLUSION: UCP1 -3826 A/G and ß3AR 64 Trp/Arg substitutions accelerate age-related decrease in BAT activity, and thereby may associate with visceral fat accumulation with age.

cAMP-GEFII is a direct target of cAMP in regulated exocytosis.

Although cAMP is well known to regulate exocytosis in many secretory cells, its direct target in the exocytotic machinery is not known. Here we show that cAMP-GEFII, a cAMP sensor, binds to Rim (Rab3-interacting molecule, Rab3 being a small G protein) and to a new isoform, Rim2, both of which are putative regulators of fusion of vesicles to the plasma membrane. We also show that cAMP-GEFII, through its interaction with Rim2, mediates cAMP-induced, Ca2+-dependent secretion that is not blocked by an inhibitor of cAMP-dependent protein kinase (PKA). Accordingly, cAMP-GEFII is a direct target of cAMP in regulated exocytosis and is responsible for cAMP-dependent, PKA-independent exocytosis.

Generation of intestinal T cells from progenitors residing in gut cryptopatches.

Cryptopatches (CPs) are part of the murine intestinal immune compartment. Cells isolated from CPs of the small intestine that were c-kit positive (c-kit+) but lineage markers negative (Lin-) gave rise to T cell receptor (TCR) alphabeta and TCR gammadelta intestinal intraepithelial T cells after in vivo transfer or tissue engraftment into severe combined immunodeficient mice. In contrast, cells from Peyer's patches and mesenteric lymph nodes, which belong in the same intestinal immune compartment but lack c-kit+Lin- cells, failed to do so. These findings and results of electron microscopic analysis provide evidence of a local intestinal T cell precursor that develops in the CPs.

Continued inhalation of lidocaine suppresses antigen-induced airway hyperreactivity and airway inflammation in ovalbumin-sensitized guinea pigs.

It is unclear whether inhaled lidocaine is effective against airway hyperreactivity and inflammation in asthma. The aim of this study was to investigate the effects of inhaled lidocaine on airway hyperreactivity and inflammation. Airway reactivity to inhaled histamine, cellular composition of bronchoalveolar lavage (BAL) fluid, plasma substance P (SP), and isolated lung tissue were evaluated in ovalbumin (OVA)-sensitized guinea pigs 7 days after OVA challenge. The effects of inhaled lidocaine on this model were also evaluated. Treatment with lidocaine was administered in two fashions: as single inhalation or inhalation bid for 7 consecutive days, for comparison with a saline-inhaled control group. Airway hyperreactivity to histamine, increase in number of total cells and increased proportion of eosinophils in BAL fluid, and marked eosinophil infiltration in airway walls were noted even 7 days after OVA challenge in the control group. Plasma SP level was also significantly increased. Although treatment with single lidocaine inhalation did not affect airway hyperreactivity, continued inhalation (bid for 7 days) attenuated airway hyperreactivity. Continued, but not single, inhalation of lidocaine also suppressed infiltration of eosinophils in BAL fluid and in airway walls. In addition, plasma SP levels were significantly reduced by continued but not by single inhalation. It appears possible that lidocaine when inhaled suppresses eosinophilic inflammation of the airway and SP-induced neurogenic inflammation, leading to alleviation of airway hyperreactivity.

Apnoea-hypopnoea index during rapid eye movement and non-rapid eye movement sleep in obstructive sleep apnoea.

This study investigated the differences in apnoea-hypopnoea index (AHI) during rapid eye movement (REM) sleep (AHI-REM) and AHI during non-REM (NREM) sleep (AHI-NREM) in patients with obstructive sleep apnoea (OSA). Nocturnal polysomnography was performed in 102 Japanese OSA patients and their AHI along with a variety of other factors were retrospectively evaluated. Regardless of the severity of AHI, mean apnoea duration was longer and patients' lowest recorded oxygen saturation measured by pulse oximetry was lower during REM sleep than during NREM sleep. Approximately half of the patients (n = 50) had a higher AHI-NREM than AHI-REM. In subjects with AHI >or= 60 events/h, AHI-NREM was significantly higher than AHI-REM. On multivariate logistic regression, severe AHI >or= 30 events/h was the only predictor of a higher AHI-NREM than AHI-REM. This may indicate that important, but unknown, factors related to the mechanism responsible for the severity of OSA are operative during NREM sleep.

Aberrant expression of microRNAs and the miR-1/MET pathway in canine hepatocellular carcinoma.

Canine hepatocellular carcinoma (HCC) is the most common primary hepatic tumour in dogs. MicroRNA (miRNA) dysregulation has been reported in human HCC and shown to have diagnostic and prognostic value; however, there are no data on miRNA expression in canine HCC. The aim of the present study was to investigate differentially expressed miRNAs in canine HCC. Analysis of miRNA expression in canine HCC tissues and cell lines by quantitative reverse transcription PCR showed that miR-1, miR-122, let-7a, and let-7g were downregulated, whereas miR-10b and miR-21 were upregulated in canine HCC. MET is one of the target genes of miR-1. MET was upregulated in canine HCC at the gene and protein levels, and a significant correlation between the concomitant downregulation of miR-1 and upregulation of MET was observed. Fast/intermediate-proliferating canine HCC cell lines had higher MET gene and protein expression levels than the slow-proliferating cell line. These findings suggest that miRNAs are differentially expressed in canine HCC, and that the miR-1/MET pathway may be associated with canine HCC cell proliferation.

Effect of sex hormones on carcinogenesis in the stomachs of rats.

We have been investigating possible effects of sex hormones on the carcinogenesis of stomach cancer in Wistar rats that were given N-methyl-N'-nitro-N-nitrosoguanidine in drinking water (50 micrograms/ml) for 4 months. The incidences of stomach cancer in intact male, intact female, castrated male, and castrated female rats at Month 4 of the experiment were 5, 0, 0, and 0% respectively; and those at Month 8 were 40, 10, 0, and 0% respectively; indicating that the incidence in intact males was much higher than in the other groups. The difference in the incidence became more evident when the animals were sacrificed at Month 12 of the experiment (81, 0, 29, and 5%, respectively). Hypertrophy and dissociation of the lamina muscularis mucosae which are considered to occur in the carcinogenic process were observed only in the male rats at the earlier months, but not in female nor in castrated rats. In N-methyl-N'-nitro-N-nitrosoguanidine carcinogenesis, female and castrated rats had a lower incidence of gastric cancers with less change in the lamina muscularis mucosae than did the nontreated male rats. These findings, therefore, suggest that, in addition to the suppressive action of female hormones, male hormones facilitate carcinogenesis.

Relationship between goblet cells and carcinoma of the pancreas during N-nitrosobis(2-hydroxypropyl)amine-induced carcinogenesis in Syrian golden hamsters.

During N-nitrosobis(2-hydroxypropyl)amine-induced pancreatic carcinogenesis in Syrian golden hamsters, both carcinoma and dysplasia could be distinctly classified into two types according to whether they did or did not contain goblet cells. Goblet cell-containing dysplasia developed mainly in the larger duct, and majority of goblet cell-containing carcinomas showed a pattern of papillary adenocarcinoma. It seems most probable that goblet cells are predysplastic and precancerous changes. On the other hand, dysplasia without goblet cells developed mainly in the smaller ductules, and a majority of carcinomas without goblet cells showed a pattern of poorly differentiated adenocarcinoma. These findings seem to correspond well with the relationship between human pancreatic cancer and mucus-secreting cells. The behavior of the goblet cells of hamster pancreatic ducts might be a good model for that of human mucus-secreting cells, especially mucous cells.

Absence of endothelial cells, central necrosis, and fibrosis are associated with aggressive inflammatory breast cancer.

We recently established a new human inflammatory breast cancer (IBC) xenograft (WIBC-9) originating from a patient with IBC. The graft was transplantable in BALB/c nude and severe combined immunodeficient (SCID) mice. WIBC-9 was frequently accompanied by lung metastasis and exhibited erythema of the overlying skin, reflecting its human counterpart. Histological study of the original tumor and WIBC-9 revealed invasive ductal carcinoma with a hypervascular structure of solid nests and marked lymphatic permeation in the overlying dermis. In the central part of the solid nests, absence of endothelial cells, central necrosis, and fibrosis were observed. In vitro, WIBC-9 formed tube-like structures and loops, reflecting its in vivo feature and its human counterpart. WIBC-9 exhibited aneuploidy, ErbB-2 gene amplification, and an absence of estrogen receptor and progesterone receptor, which is consistent with IBC. Comparative studies of WIBC-9, three established non-IBC xenografts, and a human breast cancer cell line (SK-BR3) by reverse transcription-PCR, ELISA, and immunohistochemistry indicated that certain human genes (interleukin 8, vascular epidermal growth factor, basic fibroblast growth factor, angiopoietin 13, Flt-1, Tie-2, and Tie-1) and certain murine genes (integrin alpha(v)beta3, flt-1, tie-2, vascular epidermal growth factor, and CD31) were overexpressed in exposure to tumor cells. The molecular basis and these unique histological features may be associated with aggressive IBC on angiogenic and nonangiogenic pathways.

Increased expression of sialyl Lewisx antigen correlates with poor survival in patients with colorectal carcinoma: clinicopathological and immunohistochemical study.

We have previously shown that sialyl Lewisx antigen (sLex) (NeuAc alpha 2-3Gal beta 1-4(Fuc alpha 1-3)GlcNAC-R) has an important functional role in defining the invasion and metastasis of human colorectal carcinoma. The results were derived from the clinical specimens obtained at surgery or experimental metastasis of human colon carcinoma variant expressing different levels of sLex in nude mice. In the present study, we immunohistochemically examined 132 human colorectal carcinomas for the expression of sLex to investigate whether this antigen expression could serve as a prognostic parameter. The tumors were divided into two groups: sLex positive and sLex negative. The incidence of sLex positive was correlated with the depth of tumor invasion, the presence of the lymph node metastasis, lymphatic invasion, and the disease stage. The difference was statistically significant (P = 0.0026; P = 0.0002; P = 0.003; P = 0.0013; respectively). Based on the data on 114 patients who underwent curative resections, incidence of the disease recurrence was assessed. The sLex-positive patients had higher incidence of recurrence in distant organs, especially in the liver, than that of the sLex-negative patients. The 5-year disease free survival rates of sLex-positive and -negative patients were 57.7 and 89.1%, respectively (P = 0.0002). The difference of 5-year overall survival rates between the two were also significant (sLex positive, 58.3%; sLex negative, 93.0%: P < 0.0001). By Cox multivariate analysis, sLex expression levels remained the best discriminant of disease-free survival (P = 0.035) and overall survival (P = 0.0081). These results suggest that increased expression of sLex is correlated with the extent of malignancy and high incidence of recurrence and consequently with survival of colorectal carcinoma patients. Thus sLex may prove to be a potent marker of recurrence in colorectal carcinoma patients.

Thoracic duct lymphography by subcutaneous contrast agent injection in a dog with chylothorax.

A 4-year-old male Japanese Shiba Inu presented with recurrent chylothorax. The thoracic duct was successfully imaged using computed tomography after the injection of an iodine contrast agent into the subcutaneous tissue surrounding the anus. The thoracic duct was successfully ligated and pericardectomy performed via an open thoracotomy. Pleural effusion improved but relapsed a week after the surgery. A second lymphography revealed a collateral thoracic duct that was not detected during the first lymphography. The collateral duct was ligated and chylothorax was resolved after the second surgery. The lymphography applied in this study was minimally-invasive and easily provided images of the thoracic duct in a dog with chylothorax.

Intravoxel Incoherent Motion in Normal Pituitary Gland: Initial Study with Turbo Spin-Echo Diffusion-Weighted Imaging.

BACKGROUND AND PURPOSE: DWI with conventional single-shot EPI of the pituitary gland is hampered by strong susceptibility artifacts. Our purpose was to evaluate the feasibility of intravoxel incoherent motion assessment by using DWI based on TSE of the normal anterior pituitary lobe. MATERIALS AND METHODS: The intravoxel incoherent motion parameters, including the true diffusion coefficient (D), the perfusion fraction (f), and the pseudo-diffusion coefficient (D*), were obtained with TSE-DWI in 5 brain regions (the pons, the WM and GM of the vermis, and the genu and splenium of the corpus callosum) in 8 healthy volunteers, and their agreement with those obtained with EPI-DWI was evaluated by using the intraclass correlation coefficient. The 3 intravoxel incoherent motion parameters in the anterior pituitary lobe were compared with those in the brain regions by using the Dunnett test. RESULTS: The agreement between TSE-DWI and EPI-DWI was moderate (intraclass correlation coefficient = 0.571) for D, substantial (0.699) for f', but fair (0.405) for D*. D in the anterior pituitary lobe was significantly higher than in the 5 brain regions (P < .001). The f in the anterior pituitary lobe was significantly higher than in the 5 brain regions (P < .001), except for the vermian GM. The pituitary D* was not significantly different from that in the 5 brain regions. CONCLUSIONS: Our results demonstrated the feasibility of intravoxel incoherent motion assessment of the normal anterior pituitary lobe by using TSE-DWI. High D and f values in the anterior pituitary lobe were thought to reflect its microstructural and perfusion characteristics.

Selective inhibition of 5-lipoxygenase pathway in rat pulmonary alveolar macrophages by cigarette smoking.

Pulmonary alveolar macrophages from sham or cigarette-smoke-exposed rats were examined for their ability to transform exogenously added arachidonate to metabolites of lipoxygenase and cyclooxygenase pathways. Synthesis of 5-HETE and leukotriene B4 was selectively inhibited by cigarette smoke exposure, whereas the formation of prostaglandin E2 and thromboxane B2 remained unchanged. Selective inhibition of the lipoxygenase pathway was further reflected by the reduced content of leukotriene B4 in bronchoalveolar fluid of smoke-exposed rats. These results suggest that lipoxygenase-derived products may play a unique role in smoking-induced pulmonary diseases.

Partial nuclear localization of a bovine phosphoprotein, BCNT, that includes a region derived from a LINE repetitive sequence in Ruminantia.

BCNT, named after Bucentaur, is a protein that contains a 324-amino-acid region derived from part of a long interspersed DNA sequence element (LINE) in Ruminantia. However, the unique portion is completely missing in human and mouse BCNTs. Since no significant information on their function has been obtained by homology search, we at first examined cellular localization and biochemical characteristics of bovine BCNT to get a hint on its function. Subcellular fractionation and immunohistochemical analyses using a normal bovine epithelial cell line and bovine brain revealed that a significant amount of bovine BCNT is localized in the nuclei, while the major portion is present in the cytosol. Furthermore, it was shown that bovine BCNT is a phosphoprotein and that both bovine and human BCNTs are phosphorylated by casein kinase II in vitro. These results show that BCNTs consist of a unique family, probably a substrate of casein kinase II, which may contribute further to the understanding of gene evolution.

Immunochemotherapy in human hepatocellular carcinoma using the streptococcal agent OK-432.

Twenty-one patients with nonresectable hepatocellular carcinoma (HCC) received intraarterial infusion chemotherapy of Adriamycin (Adria Laboratories, Columbus, Ohio) via an indwelling catheter in the hepatic artery. Additional intratumoral injection therapy of OK-432 (50 KE) was administered to ten of these 21 patients. Nine of the ten patients showed a remarkable decrease in lymphocyte count on the first day after therapy. In all of the patients with a decreased lymphocyte count, computed tomograms (CTs) demonstrated evidence of necrosis associated with a rapid decrease in alpha fetoprotein (alpha-FP). Blastogenesis of lymphocytes in peripheral blood induced by phytohemagglutinin (PHA) increased by 3.99 +/- 1.9 (mean +/- SE) times 4 weeks after therapy. On the basis of these results, we concluded that intratumoral injection therapy of OK-432 apparently produced initiation of necrosis in HCC by cell-damaging activity as well as by improvement of cell-mediated immunity.

Expression of carbohydrate antigen sialyl Le(a): a new functional prognostic factor in gastric cancer.

PURPOSE: The prognostic value of the altered expression of carbohydrate antigens sialyl Le(a) (sLe(a)) and sialyl Le(x) (sLe(x)), which have been implicated as functional ligands in heterotypic-cell-adhesion systems in the multistep process of tumor metastasis, were evaluated. PATIENTS AND METHODS: The level of expression of sLe(a) and sLe(x) antigens was examined immunohistochemically in paraffin-embedded tumor samples from 137 patients who underwent resection for gastric cancer. Correlation between the antigens' expression, various established clinicopathologic factors, and prognosis were studied by univariate and multivariate analysis. RESULTS: Tumors that were positive for the sLe(a) antigen were significantly more likely to be large (P = .035), to be localized at the proximal third of the stomach (P = .018), to have an infiltrate appearance (P = .013), to have an invasive mode both in depth of invasion (P = .028) and in lymphatic invasion (P = .002), and to be classified as late stage (P = .011) than those that were negative for sLe(a), whereas the sLe(x) antigen status was not correlated with any clinicopathologic factors. The overall survival of patients with an sLe(a)-antigen-positive tumor was significantly poorer than that of those with an sLe(a)-antigen-negative tumor (P = .0001). Survival within each pathologic stage differed also (stage I, P = .030; stage II, P = .046; stage III, P = .026, respectively). A Cox regression analysis with multiple covariates showed that positive sLe(a) antigen status was an independent prognostic factor for a worse outcome in patients with gastric cancer. According to the mode of recurrence, increased sLe(a) antigen expression significantly affected both peritoneal dissemination and liver metastasis. CONCLUSION: Increased expression of the sLe(a) antigen may serve as a potent prognostic indicator for recurrence in patients with gastric cancer. Careful follow-up and intensive therapy are required for patients with an sLe(a)-antigen-positive gastric cancer.

Diverse roles of K(ATP) channels learned from Kir6.2 genetically engineered mice.

The regulation of insulin secretion from pancreatic beta-cells depends critically on the activities of their plasma membrane ion channels. ATP-sensitive K+ channels (K(ATP) channels) are present in many cells and regulate a variety of cellular functions by coupling cell metabolism with membrane potential. The activity of the K(ATP) channels in pancreatic beta-cells is regulated by changes in the ATP and ADP concentrations (ATP/ADP ratio) caused by glucose metabolism. Thus, the K(ATP) channels are the ATP and ADP sensors in the regulation of glucose-induced insulin secretion. K(ATP) channels are also the target of sulfonylureas, which are widely used in the treatment of type 2 diabetes. Molecular cloning of the two subunits of the pancreatic beta-cell K(ATP) channel, Kir6.2 (an inward rectifier K+ channel member) and SUR1 (a receptor for sulfonylureas), has provided great insight into its structure and function. Kir6.2 subunits form the K+ ion-permeable pore and primarily confer inhibition of the channels by ATP, while SUR1 subunits confer activation of the channels by MgADP and K+ channel openers, such as diazoxide, as well as inhibition by sulfonylureas. The SUR1 subunits also enhance the sensitivity of the channels to ATP. To determine the physiological roles of K(ATP) channels directly, we have generated two kinds of genetically engineered mice: mice expressing a dominant-negative form of Kir6.2 specifically in the pancreatic beta-cells (Kir6.2G132S Tg mice) and mice lacking Kir6.2 (Kir6.2 knockout mice). Studies of these mice elucidated various roles of the K(ATP) channels in endocrine pancreatic function: 1) the K(ATP) channels are the major determinant of the resting membrane potential of pancreatic beta-cells, 2) both glucose- and sulfonylurea-induced membrane depolarization of beta-cells require closure of the K(ATP) channels, 3) both glucose- and sulfonylurea-induced rises in intracellular calcium concentration in beta-cells require closure of the K(ATP) channels, 4) both glucose- and sulfonylurea-induced insulin secretions are mediated principally by the K(ATP) channel-dependent pathway, 5) the K(ATP) channels are important for beta-cell survival and architecture of the islets, 6) the K(ATP) channels are important in the differentiation of islet cells, and 7) the K(ATP) channels in glucose-responsive cells generally participate in coupling glucose sensing with cell excitability. Interestingly, despite the severe defect in glucose-induced insulin secretion, Kir6.2 knockout mice show only a very mild impairment in glucose tolerance. However, when the knockout mice become obese with age, they develop fasting hyperglycemia and glucose intolerance, while neither fasting hyperglycemia nor glucose intolerance is evident in the aged knockout mice without obesity, suggesting that both the genetic defect in glucose-induced insulin secretion and the acquired insulin resistance due to environmental factors are necessary to develop diabetes in Kir6.2 knockout mice. Thus, Kir6.2G132S Tg mice and Kir6.2 knockout mice provide a model of type 2 diabetes and clarify the various roles of K(ATP) channels in endocrine pancreatic function.

Roles of ATP-sensitive K+ channels in cell survival and differentiation in the endocrine pancreas.

To determine the roles of the ATP-sensitive K+ (K(ATP)) channels in endocrine pancreas more directly, two types of genetically engineered Kir6.2 mice were developed: mice expressing a dominant-negative form of Kir6.2 specifically in beta-cells (Kir6.2G132S Tg mice) and mice lacking Kir6.2 (Kir6.2-/- or Kir6.2 null mice). The Kir6.2G132S Tg mice show severe impairment of K(ATP) channel function only in the beta-cells, whereas Kir6.2 null mice are completely defective in K(ATP) channel function in all of the cells in which Kir6.2 is a constituent of the K(ATP) channels, because of the disruption of Kir6.2. Both types of mice show abnormal architecture of the pancreatic islets. The number of beta-cells in Kir6.2G132S Tg mice decreases markedly with age, whereas that in Kir6.2-/- mice decreases slightly. alpha-Cells, which are normally present only in the periphery of pancreatic islets, also appear in the center of the islets in both Kir6.2G132S Tg and Kir6.2-/- mice. Interestingly, the number of peptide YY (PYY) and glucagon-positive cells is markedly increased in Kir6.2 null mice, whereas the number of PP cells and delta-cells is not altered. Apoptotic cells are detected by the TdT-mediated dUTP nick-end labeling (TUNEL) method at a high frequency in both Kir6.2G372S Tg and Kir6.2-/- mice compared with the respective controls. Thus, studies of Kir6.2G372S Tg and Kir6.2-/- mice indicate that K(ATP) channels play an important role in cell survival and differentiation in the endocrine pancreas.