Effect of low power Er:YAG laser irradiation of CAD-CAM resin-based composites on resin bonding.

PURPOSE: To investigate the effect of painless low-power Er:YAG laser irradiation of conventional and polymer-infiltrated ceramic network (PICN) type CAD-CAM resin-based composites (RBCs) on resin bonding. METHODS: An Er:YAG laser system, phosphoric acid etchant, universal adhesive, RBC, and two types of CAD-CAM RBC block were used. Microtensile bond strength, fracture mode, scanning electron microscopy (SEM) observations of bonding interfaces and CAD-CAM surfaces, and surface roughness of ground and pretreated surfaces were investigated. As pretreatment methods, low-power Er:YAG laser irradiation and air-abrasion with alumina particles were used. RESULTS: The effect of low-power Er:YAG laser irradiation of CAD-CAM RBCs on bonding to repair resin varied depending on the type of CAD-CAM RBCs. CLINICAL SIGNIFICANCE: The low-power Er:YAG laser irradiation of the conventional CAD-CAM RBCs was shown to be effective as a surface pretreatment for resin bonding, while the laser irradiation of PICN-type CAD-CAM RBCs was not effective.

Evaluation of the Repolished Surface Properties of a Resin Composite Employing Structural Coloration Technology.

Resin composites employing structural coloration have recently been developed. These resins match to various tooth shades despite being a single paste. To accomplish this, the filler and base resin are tightly bonded, which is thought to provide excellent discoloration resistance. Here, we investigated the surface properties of one of these resins, including the discoloration of the repolished surface. We developed an innovative in vitro method to adjust the repolished surface, in which structural degradation is removed according to scanning electron microscopy (SEM) observation rather than by the naked eye. The resin samples (20 mm (length) × 10 mm (width) × 4 mm (depth)) were manufactured using this resin material. After accelerated aging of the resin by alkaline degradation, the resin was repolished and the discoloration (ΔE*ab), surface roughness (the arithmetic mean roughness (Ra)), and glossiness (the 60° specular) were measured. SEM observation showed that the appearance of the bond between the organic composite filler and base resin on the repolished surface was different from that on the mirror-polished surface. This revealed that according to our in vitro method it was difficult to make the repolished surface structurally identical to the mirror-polished surface. Among the properties of the repolished surface, the degree of discoloration did not change despite the rougher and less glossy surface. It can be concluded that the factors that induce discoloration in this resin composite are independent of the surface roughness and glossiness.

Acute portal vein thrombosis due to chronic relapsing pancreatitis: a fistula between a pancreatic pseudocyst and the splenic vein.

Portal vein thrombosis (PVT) is a relatively common complication in patients with liver cirrhosis, but several other causes might play an important role in PVT pathogenesis. We present a case of alcoholic chronic pancreatitis complicated by acute extensive PVT. The patient was managed conservatively with danaparoid sodium at first, but the thrombosis gradually extended. We then tried radiological intervention using the direct transhepatic and transjugular intrahepatic postsystemic shunt approaches. Although we were able to successfully catheterize the percutaneous transhepatic portal vein (PTP), we could not achieve recanalization of the portal vein. Therefore, PTP catheterization and systemic intravenous infusion of urokinase and heparin was performed to prevent further progression of the thrombosis and cavernous transformation was finally achieved. Computed tomography (CT) and magnetic resonance cholangiopancreatography revealed a pancreatic stone which had possibly induced dilatation of the tail duct and formation of a pancreatic pseudocyst and caused intractable pancreatitis. We performed endoscopic retrograde cholangiopancreatography and placed a stent in the pancreatic duct, which completely cured the pancreatitis. Retrospectively, the previous CT with curved multi-planar reconstruction was reviewed and a fistula was detected between the pancreatic pseudocyst and splenic vein. We concluded that the etiology of the PVT was not only inflammatory extension from pancreatitis but also a fistula between the pancreatic duct and the splenic vein.

Short-chain fatty acids increase the level of calbindin-D9k messenger RNA in Caco-2 cells.

Fructooligosaccharides (FOS) are indigestible oligosaccharides that increase the expression of calbindin-D9k and consequently increase calcium absorption by the colon in rats. The molecular mechanism of the increased expression of calbindin-D9k resulting from FOS ingestion has not been elucidated. Short-chain fatty acids (SCFAs), namely, fermentation products of FOS by intestinal bacteria have been hypothesized as direct effectors of calbindin-D9k gene expression. To test this hypothesis, SCFAs were added to Caco-2 human intestinal epithelial cells, and changes in the levels of transcription of genes for calbindin-D9k, and transcription factors (vitamin D receptor: VDR, caudal homeobox-2: Cdx-2, hepatocyte nuclear factor 1-α: HNF1-α) were determined by quantitative reverse transcription polymerase chain reaction. Addition of sodium propionate or sodium butyrate to cell cultures increased levels of calbindin-D9k mRNA to 731% (p<0.05) and 321% (p<0.05), respectively. However, addition of these SCFAs did not affect the levels of mRNA VDR, Cdx-2, or HNF1-α. In conclusion, addition of SCFAs to cultured Caco-2 cells results in elevation of calbindin-D9k mRNA, consistent with the expected role of SCFAs as mediators of the increase of calcium absorption in rats that were fed with FOS.

Effects of topical application of ibudilast for seasonal allergic conjunctivitis in patients wearing soft contact lenses.

PURPOSE: To assess the influence of topical application of ibudilast for seasonal allergic conjunctivitis in patients wearing soft contact lenses (SCLs). MATERIALS AND METHODS: There were 16 SCL wearers (32 eyes) with allergic conjunctivitis due to cedar pollen, who were studied from February to April 2007. Before enrollment, informed consent to participation in this study was obtained from all subjects. A frequent replacement SCL (2 Week Pure) was worn for 2 weeks, and ibudilast was applied topically four times daily during this period. The severity of allergic symptoms and the severity of SCL-related symptoms were assessed by scoring using two questionnaires, and before and after topical application of ibudilast results were compared. The severity of objective ocular findings was also scored and compared in the same way. After the final examination, the SCLs were collected and immersed in physiologic saline. Then morphologic changes and drug adsorption were investigated. RESULTS: Among the allergic symptoms, itching and a dry sensation improved after topical application of ibudilast ophthalmic solution (both P<0.05). Phlyctenular conjunctivitis was noted in one eye after topical application, but there were no significant differences of SCL-related symptoms and objective ocular findings between before and after application. There were also no morphologic changes of the contact lenses, and the ibudilast concentration in the lenses was below the detection limit. CONCLUSIONS: These results suggest that topical application of ibudilast while using 2 Week Pure lenses can improve subjective symptoms without influencing drug adsorption or lens morphology.

Short-chain fatty acids induce intestinal transient receptor potential vanilloid type 6 expression in rats and Caco-2 cells.

Fructooligosaccharides (FOS) are indigestible oligosaccharides that increase calcium absorption by the colorectum in rats, but the underlying mechanisms remain unclear. We therefore investigated the effects of FOS on expressions of genes involved with calcium absorption in rat colorectal mucosa cells. After feeding a diet containing FOS (100 g/kg diet) to rats for 2 d, we investigated gene transcripts of transient receptor potential vanilloid type 6 (TRPV6), calbindin-D9k, and plasma membrane calcium-ATPase 1b (PMCA1b). The FOS diet increased expression of TRPV6 and calbindin-D9k but did not affect PMCA1b expression. Because FOS could not directly affect gene expression, SCFA formed as fermentation products of FOS were considered as likely intermediates. SCFA (2.0 mmol/L) were thus added to Caco-2 human colonic epithelial cells, resulting in significantly increased mRNA expression of TRPV6. To ascertain the effects of SCFA on mRNA expression, a genomic clone of TRPV6 was isolated. Using luciferase reporter assay, a segment between -71 nucleotides and the translation start site was found to contain a positive responsive element to SCFA. These results suggest that FOS increase calcium absorption by increasing mRNA expression of TRPV6 in rat colorectum, and cell culture analysis indicated that SCFA, as fermentation products of FOS, are involved in the increased mRNA expression of TRPV6. We found for the first time, to our knowledge, that regulation of TRPV6 gene expression by SCFA may be a molecular mechanism involved in the promotion of calcium absorption by FOS in rats.

Combined genotoxic effects of radiation and a tobacco-specific nitrosamine in the lung of gpt delta transgenic mice.

It is important to evaluate the health effects of low-dose-rate or low-dose radiation in combination with chemicals as humans are exposed to a variety of chemical agents. Here, we examined combined genotoxic effects of low-dose-rate radiation and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), the most carcinogenic tobacco-specific nitrosamine, in the lung of gpt delta transgenic mice. In this mouse model, base substitutions and deletions can be separately analyzed by gpt and Spi- selections, respectively. Female gpt delta mice were either treated with gamma-irradiation alone at a dose rate of 0.5, 1.0 or 1.5 mGy/h for 22 h/day for 31 days or combined with NNK treatments at a dose of 2 mg/mouse/day, i.p. for four consecutive days in the middle course of irradiation. In the gpt selection, the NNK treatments enhanced the mutation frequencies (MFs) significantly, but no obvious combined effects of gamma-irradiation were observable at any given radiation dose. In contrast, NNK treatments appeared to suppress the Spi- large deletions. In the Spi- selection, the MFs of deletions more than 1 kb in size increased in a dose-dependent manner. When NNK treatments were combined, the dose-response curve became bell-shaped where the MF at the highest radiation dose decreased substantially. These results suggest that NNK treatments may elicit an adaptive response that eliminates cells bearing radiation-induced double-strand breaks in DNA. Possible mechanisms underlying the combined genotoxicity of radiation and NNK are discussed, and the importance of evaluation of combined genotoxicity of more than one agent is emphasized.

Predictive factors for the response to lamivudine in HBV-infected patients with chronic hepatitis and cirrhosis.

OBJECTIVE: To determine predictors for virological response to lamivudine, a retrospective-cohort study was designed. METHODS: Seventy HBV positive patients who received lamivudine were classified according to virological response into responders and non-responders. Background conditions and normalization and flare-up of hepatitis were compared using student-t test and chi-square test. Logistic regression analysis was performed to determine the effect of explanatory variables, age, sex, ALT, HBV-DNA, hepatic fibrosisi, presence of absence of HBeAg, former IF non-response on the response to lamivudine. RESULTS: There were no difference in gender, age, observed period, ALT level, liver fibrosis, former response to Interferon in background but viral titer and rate of HBeAg (+) was higher in non-responders. Hepatitis normalization rates were not different but flare-up rates were significantly higher in non-responders. Multivariate analysis showed HBeAg is the relevant factor for the response to lamivudine. CONCLUSIONS: The presence of HBeAg was a risk for non-response to lamivudine therapy.

Serotonin transporter polymorphisms affect human blood glucose control.

We measured the effect of nutritional intervention on clinical data, including fasting blood glucose (FBG), and their association with polymorphisms of the serotonin transporter-linked polymorphic region (5-HTTLPR) which might affect adherence. Enrolled in the intervention program were 264 Japanese women not on medication for diabetes, hypercholesterolemia or hypertension. The 5-HTTLPR allele (S and L) frequencies among the subjects differed markedly from those of Caucasians: SS (n = 183), LS (n = 69), and LL (n = 12). The decrease in FBG (DeltaFBG) from the beginning to the end of the program (11 weeks; short-term study), and DeltaFBG from the beginning to a follow-up check performed between 2002 and 2004 (average of 23 years later; long-term study) was calculated. The SS homozygotes of 5-HTTLPR showed larger DeltaFBG (P = 0.01 and P < 0.0001 in the short- and long-term studies, respectively) than DeltaFBG with other genotypes.

Expression of calbindin-D9k, VDR and Cdx-2 messenger RNA in the process by which fructooligosaccharides increase calcium absorption in rats.

We have previously shown, through evidence that the expression of calbindin-D9k protein shows a dose-dependent change in the intestine, that calbindin-D9k plays a role in the ability of a fructooligosaccharide (FOS) diet to increase calcium absorption. This study shows that the regulation of calbindin-D9k expression occurs at the transcriptional level in a segment-specific manner, decreasing in the proximal intestine and increasing in the colorectal segment. To determine the transcriptional regulation of the FOS diet on calbindin-D9k expression, two transcription factors, vitamin D receptor (VDR) and cdx-2, were analyzed during 10 d feeding of the FOS diet. The mRNA expression of VDR and cdx-2 was influenced by the FOS diet and showed a segment-specific change. In the proximal small intestine, there was a significant correlation between the changes in both mRNAs (r = 0.69, p < 0.01), while the expression of calbindin-D9k correlated neither with VDR nor with cdx-2. This means that the transcriptional change induced by the FOS diet was not regulated by VDR and cdx-2. In the colorectal segment, there were significant correlations between gene expressions of calbindin-D9k vs. VDR, r = 0.73, p < 0.01 and calbindin-D9k vs. cdx-2, r = 0.52, p < 0.05. These results suggested that both transcription factors, VDR and cdx-2, were involved in the regulation of calbindin-D9k gene expression in the colorectal segment during the process through which the FOS diet enhanced calcium absorption.

The specific expression patterns of lactase, sucrase and calbindin-D9k in weaning rats are regulated at the transcriptional level.

During weaning, rat lactase-phlorizin hydrolase (LPH) expression decreased to the low levels found in adults, while sucrase-isomaltase (SI) sharply increased. Calbindin-D9k (CaBP) is specific to the intestine and expression peaked within a few days of weaning. The present study investigates whether these molecules are regulated at transcriptional or post-transcriptional levels and examines the effects of diet on regulation. At normal weaning on day 21, litters were separated from their dams and one group was fed with a standard laboratory diet (weaned (W) group). The other group received a diet containing lactose as the sole source of carbohydrate (lactose-fed (L) group). Mucosal cells were obtained from the proximal part of the rat small intestine and then the activity and concentration of LPH, SI and CaBP proteins and mRNAs were determined. Three parameters revealed the same changing patterns in LPH, SI and CaBP during development and there was significant (p<0.001) correlation between three parameters: LPH, r=0.97 for activity vs. protein, r=0.99 for activity vs. mRNA, r=0.96 for protein vs. mRNA, SI, r=0.99 for activity vs. protein, r=0.98 for activity vs. mRNA, r=0.96 for protein vs. mRNA, CaBP, r=0.94 for activity vs. protein, r=0.97 for activity vs. mRNA, r=0.95 for protein vs. mRNA. Expression of the three proteins did not differ between the L and W groups. Accordingly, it has been suggested that the expression of LPH, SI and CaBP during development is defined at the transcriptional level and dietary changes do not exert a primary effect on it.

The effect of fructooligosaccharides was analyzed by cDNA expression arrays.

We have already reported that indigestible fructooligosaccharides (FOS) increased calcium absorption in rat large intestines and that calbindin-D9k (CaBP), which is an intestine-specific calcium-binding protein, is involved in that increasing effect. In this study, not only the CaBP gene, every gene that changed expression profiles as the result of FOS feeding was identified by cDNA expression arrays. Sprague-Dawley male rats were fed an experimental diet containing 10% FOS for 10 d. To compare gene expression with rats fed a control diet, total mRNA was extracted from the colorectum and analyzed using a Rat cDNA Expression Arrays filter. This arrays filter contains probes of 588 genes, and 195 of them showed detectable changes in their expression by FOS feeding. There were six genes that increased their expression more than twice that of the control. Among them, genes related to the induction of cell growth such as Map kinase 1 and Max were included. Expressions that decreased to less than half were observed in 20 genes, such as somatostatin and prohibitin, which prohibit cell growth. These results are consistent with the other observation that FOS increases cell growth in the colorectum. This approach has revealed that cDNA array technology is an effective tool for nutritional sciences that involve the regulation of a large number of genes, especially for molecular mechanisms of regulation, by nutritional constituents.

Bisphenol A induces apoptosis in central neural cells during early development of Xenopus laevis.

Bisphenol A (BPA), known to be a xenoestrogen, is widely used in industry and dentistry. In the present study, we investigated the effects of BPA on the early development of Xenopus laevis embryos. Stage 6 embryos were exposed to 10-100 microM BPA. Developmental abnormalities were observed when the embryos were exposed to at least 20 microM BPA, with marked developmental abnormalities, such as crooked vertebrae and developmental defects of the head and abdomen, detected in all embryos up to stage 40. Interestingly, apoptosis occurred specifically in central nervous tissue cells of the brain and spinal cord, as assessed by histological analysis. BPA-induced malformations and apoptosis were not observed in embryos exposed to BPA after stage 10. When embryos were exposed to 10 microM 17beta-estradiol (E2), abnormalities were also observed until stage 40. However, the abnormalities induced by BPA and E2 were different and E2 exposure did not induce apoptosis in the central nervous system. Our results indicated that the developmental abnormalities and apoptosis induced by BPA exposure were not inhibited by the addition of E2. In conclusion, we demonstrated that BPA induced marked malformations and specific apoptosis of central nervous system cells during early development of X. laevis embryos, and that these BPA effects appeared to be due to non-estrogenic activities on developmental processes.

Somatic symptoms for diagnosing major depression in cancer patients.

Diagnosing depression in cancer patients has been challenging because the diagnostic criteria include somatic symptoms frequently attributed to the cancer itself or its treatment. However, few studies have explored how to appropriately deal with individual somatic symptoms. The authors used data from 220 cancer patients with major depression to examine the intercorrelations among the DSM-IV somatic and nonsomatic symptom criteria as well as whether the presence of an individual somatic symptom could discriminate the severity of major depression. Appetite changes and a diminished ability to think were positively associated with anhedonia. Sleep disturbance and fatigue were not significantly associated with nonsomatic symptoms. These associations were consistent after adjusting for physical functioning and pain. Only patients with appetite changes showed a higher severity of depression. These results suggest that individual somatic symptoms differ in nature and that appetite-related symptoms and a diminished ability to think may be useful for diagnosing depression in cancer patients, whereas sleep disturbances and fatigue may not be as useful.