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http://hdl.handle.net/2003/25615

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J. G. Hengstler
Leibniz Research Centre for Working Environment and Human Factors
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L. S. Weilemann, Mainz, Germany
I. Ishibashi, Tokyo, Japan
P. Micke, Uppsala, Sweden
J. Timmer, Freiburg, Germany
A. Winterpacht, Erlangen, Germany
B. C. Behera, Pune, India

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Wireless capsule endoscopy exploration for diseases of the small intestine in China
(2007-10-29) Bai, Changqing; Fang, Guangrong; Song, Jian; Wang, Qunying; Yan, Li; Zhong, Zhong
For small bowel diseases, it is difficult for the ordinary enteroscopy to reach due to its specific curvature and length. Capsule endoscopy (CE) is a unique tool to visualize the mucosa of the small intestine. The aim of this study was to evaluate the detection rate and diagnostic yield of CE in a large group of patients with suspected digestive diseases in China. One hundred and two consecutive patients (75 male, mean age 50 years, range 32-87 years) underwent CE in our Gastroenterology Units, for a total of 102 procedures. Referrals were obscure occult/ overt gastrointestinal bleeding group (19 patients) and suspected small bowel disease group (83). In our study, the whole detection rate was 92 % (94/102), with a definite diagnosis yield of 63 % of the patients in the obscure gastrointestinal bleeding and 39 % of the patients in the suspected small bowel diseases. None of the patients developed symptoms of signs of mechanical obstruction, although the capsule was retained in the stomach in 2/102 patients for their somatostatin taken. CE seems to be a very safe, painless and effective procedure with a high diagnostic yield. Accurate selection of indications and critical evaluation of the results are essential to explore these diseases.
Primary aromatic amines
(2007-09-01) Schupp, Thomas; West, Robert J.
3,4-Dichloroaniline (DCA) showed an unusually high bioconcentration factor (BCF) up to 800 in the sediment dweller Lumbriculus variegatus, exceeding BCFs found in fish and other aquatic organisms by a factor of 8-40. In the scope of the European Risk Assessment process for different aromatic amines, concern was expressed with regards to biomagnification and secondary poisoning of man. Although measured BCF data in fish may be not critical, biomagnification in food chain of sediment, sediment dwelling organisms, fish eating birds or mammal (including man) can not be excluded. To address this issue, the concentration of DCA in fish due to dietary uptake via L. variegatus (i. e., the biomagnifications factor, BMF) was calculated, based on two different assumptions: 1) Either DCA is accumulated in L. variegatus in the form of a metabolite, but instantaneously released as DCA in fish, or 2) a DCA metabolite is accumulated in L. variegatus and further accumulated in fish. In the first case, application of an existing experimental kinetic model showed that the experimental BCF is likely to increase from 22 to approx. 25 if uptake via food has to be taken into account. In the second case, use of a physiology-based toxicokinetic model (PBTK) resulted in a BCF of 1.7 to 46 for the DCA metabolite. The daily uptake for a consumer, given in the European Union Risk Assessment Report for DCA, would rise by 0.6 to 1.3 %. These analyses demonstrate that biomagnifications via sediment organisms is an exposure route that deserves attention in environmental risk assessments. However, the bioconcentration factor established in sediment organisms may overestimate the threat for human beings. The use of PBTK modeling is proposed as a means of estimating the increased daily uptake for a consumer.
Appropriate Technology for the Bioconversion of Water Hyacinth (Eichhornia crassipes) to Liquid Ethanol
(2007-06-08) Isarankura-Na-Ayudhya, Chartchalerm; Kongpanpee, Thikamporn; Prabkate, Ponpitak; Prachayasittikul, Virapong; Tantimongcolwat, Tanawut
This article appraises the need for introducing appropriate technology to improve the production of renewable energy, particularly on the community basis and social aspect of sustainability. Using two-sequential steps of acid hydrolysis (10% sulfuric acid) and yeast (Candida shehatae; xylose-fermenting yeast) fermentation, bioconversion of water hyacinth (Eichhornia crassipes; a noxious weed and fast growing aquatic plant widely distributed in many tropical regions of the world) to liquid ethanol has successfully been performed. The maximum ethanol yield coefficient of 0.19 g g-1 WH with the productivity of 0.008 g l-1 h-1 was achieved. This is as well comparable to those obtained from the enzymatic saccharification and/or the fermentation of acid-pretreated water hyacinth hydrolysate using fully-equipped fermenter reported elsewhere. More importantly, determinations of xylose and ethanol contents can potentially be performed using two reliable colorimetric approaches (Phloroglucinol and Dichromate assays, respectively) in conjunction with home-made portable photometer. The technology presented herein can be transferred and implemented to gain opportunity of becoming self-reliance of community in the third world countries.
Protective effect of antioxidative vitamins against lipid eroxidation in liver ischemia and reperfusion
(2007-05-31) Bartels, Michael; Biesalski, Hans K.; Engelhart, Karin; Faber, Sonya; Gerstenbergk, Bolko von; Kassahun, Woubet T.; Meyer zu Vilsendorf, Andreas; Meyer zu Vilsendorf, Elisabeth
Ischemia and reperfusion (I/R) leads to oxidative stress with free radical formation. With respect to liver surgery and transplantation this can lead to deleterious clinical effects. Protection of the liver against I/R injury is of major concern. Thus, in this study, we examined the effect of an antioxidant vitamin solution (vitamin E, C and ß-carotene) on warm I/R injury. Twelve pigs of the German landrace (7 animals in the vitamin group and 5 untreated controls) were examined in this animal model. Twenty-four hours before laparotomy, the vitamin group was initiated with a single intravenous infusion of the vitamin cocktail. The duration of complete warm ischemia of the liver was 4 hours. Serum liver enzyme levels (AST and ALT) and with thiobarbituric acid reacting substances (TBARS) in liver tissue were measured. Furthermore, immunohistochemical staining of oxidative products (oxidized proteins and 4-hydroxy-nonenal = 4-HNE) in liver tissue was made. The maximum accumulation of oxidized proteins was seen six days postoperatively in the controls whereas in the vitamin group only small amounts were seen. 4-HNE showed a marked accumulation in the controls but was almost not detectable in the vitamin group. TBARS were lower in the vitamin group compared to controls. Although the emulsifier necessary for the vitamin solution leads to increased liver enzyme levels in the vitamin group, the values returned to normal more rapidly. Antioxidant vitamins are able to improve warm I/R liver injury. Oxidative stress is directly verifiable at the tissue level. Future animal experiments as well as clinical trials are necessary to explore the optimization of the combination of antioxidative vitamins for the maximum protection from I/R injury.
The role of a2ß1 integrin in anchorage dependent apoptosis of breast carcinoma and hepatoma cells
(2007-05-31) Berman, A. E.; Kozlova, N. I.; Morozevich, G. E.; Preobrazhenskaya, M. E.; Shtil, A. A.; Ushakova, N. A.
The role of collagen specific a2ß1 integrin in anchorage dependent apoptosis (anoikis) was investigated. Stimulation of a2ß1 signaling with immobilized anti-a2 antibody markedly sensitized human MCF-7 breast carcinoma and HepG2 hepatoma cells to anoikis. Accordingly, down-regulation of a2ß1 by a2-specific siRNA decreased the percentage of cells undergoing anoikis. These results for the first time provide direct evidence that a2ß1 receptor can transduce the signal to promote death in matrix deprived cells.
Expression profiles of a drug metabolizing enzyme CYP3A62 mRNA in the intestine of rats
(2007-05-07) Horibe, Sayo; Kishi, Hisato; Kitada, Noriaki; Ohnishi, Noriaki; Takara, Kohji; Yokoyama, Teruyoshi; Yoshikawa, Eri
The purpose of this study was to examine the expression profiles of a drug metabolizing enzyme cytochrome P450 (CYP) 3A62 mRNA in the intestine and liver of normal male Wistar rats, and its regional differences in the intestinal tract. Nine-week-old male rats were used, and their intestine were divided equally into nine segments. The expression patterns of CYP3A62 mRNA in the intestine and liver were examined using a reverse transcription-polymerase chain reaction (RT-PCR). The PCR products for CYP3A62 mRNA were readily detectable in the intestine of normal male rats, whereas no bands for CYP3A62 mRNA were detected in the liver using similar PCR conditions as those used in the intestine. The expression of CYP3A62 mRNA was found to be high in the jejunum, and stable until the bottom of the small intestine. Only the decreased expression pattern in the bottom of the intestine was contradictory to our previous findings on CYP3A9 and CYP3A18 mRNAs. Unlike other CYPs of the CYP3A subfamily, CYP3A62 was found to be predominant in the intestine rather than the liver of normal male Wistar rats. This suggests that CYP3A62 also has an important role in the detoxification of xenobiotics similar to endogenous substances as an absorptive barrier in the intestine. These findings may help the evaluation of gastrointestinal drug absorption and drug-drug interaction in rats.
The Role of Anti- and Pro-apoptotic Cofactors in Hypoxia/Reoxygenation-Dependent Regulation of MAPKs in the Brain of an Anoxia-Tolerant Model
(2007-04-10) Haddad, John J.
The cellular and molecular regulation of MAPKs and apoptosis was investigated in a model of hypoxiatolerance. Survival of neurons in Chrysemys picta bellii, an anoxia-tolerant turtle, involves a reduction in energy metabolism. The biochemical/physiological mechanisms of anoxia tolerance have been examined at the level of ion transport and ATP turnover. However, changes in the phosphorylation state of key enzymes and kinases, mainly, MAPKs, may occur during anoxia, thereby reversible protein phosphorylation could be a critical factor and major mechanism of metabolic reorganization for enduring anaerobiosis. If a turtle were to undergo hypoxia akin to that experienced in its native habitat, it was placed in a glass aquarium filled with water to within a half inch of the top. After the turtle was anesthetized, through extended hypoxia or anesthesia, the animal was sacrificed by decapitation. The brain was then excised and placed in anoxic artificial cerebrospinal fluid. Total protein extraction was performed by homogenizing brain in a buffer, followed by threonine and tyrosine phosphorylation determination of MAPKs, and caspase activity. MAPKp38 was decreased after reoxygenation following 1 day and 1 week hypoxia. The effect of hypoxia on the phosphorylation of MAPKERK was biphasic: Enhancement at 5h and inhibition at 6 weeks. Pro-caspases 8/9 were unchanged by hypoxia until increasing at 6 weeks. Both pro-caspases were upregulated by reoxygenation at 1 day or 6 weeks hypoxia. Neither hypoxia nor reoxygenation induced the cleavage of pro-caspases 8/9 into p20 and p10, respectively. Furthermore, hypoxia induced Bax at 3 days and 1 week, and reoxygenation increased Bax - 4-fold at 1 day. Although the expression of Bcl-2 was slightly increased by hypoxia, [Bcl-2] was 3-4-fold smaller in comparison with Bax. These results indicate that hypoxia up-regulates MAPKERK but not MAPKp38; hypoxia/reperfusion increases the expression of caspases and pro-apoptotic cofactors. The patterns of MAPK regulation suggest the significance of these kinases in cellular adaptation to oxygen deprivation with biomedical correlations, and thereby identify novel natural responsive signaling cofactors in Chrysemys picta bellii with potential pharmacologic and clinical applications.
Intracellular Delivery of Recombinant alpha B-crystallin into Neonatal Rat Cardiomyocytes has a Protective Effect on the Cells
(2007-04-10) Jiang, Lei; Liu, Shuang; Wang, Kangkai; Xiao, Weimin; Xiao, Xianzhong; Yuan, Can
In order to deliver alpha B-crystallin (alpha B-C) into cardiomyocytes and study its cellular protection, the full-length cDNA fragment encoding human alpha B-C was cloned into the bacterial expression vector pGEX-MTS containing the base sequence of membrane-translocating sequence (MTS) which mediates intracellular delivery of peptides and expressed as a fusion protein coupled to glutathione S-transferase (GST).After glutathione affinity chromatography and cleaved from GST by factor Xa, the recombinant MTS- alpha B-C was separated from GST and factor Xa by anion exchange chromatography. Recombinant MTS- alpha B-C was characterized by SDS-PAGE and Western immunoblot analysis. The purified MTS- alpha B-C migrated on SDS-PAGE as a single band to an apparent molecular weight (Mr.23kD) that corresponded to total native alpha B-C plus MTS, and was recognized on Western immunoblot by anti-human alpha B-crystallin antibody. MTS- alpha B-C displayed chaperone-like function in an ATP-containing buffer at 37? by disaggregating the denatured and aggregated actin induced by hydrogen peroxide (H2O2 )treatment. It was observed under fluorescence microscope that FITC-labeled MTS- alpha B-C had gone into neonatal rat cardiomyocytes by MTS mediation after the cells were incubated with it for 6 hours while FITC-labeled alpha B-C and bovine serum albumin had not gone into the cells. Recombinant MTS- alpha B-C is not cytotoxic, and MTS- alpha B-C-treated cells displayed increased H2O2-tolerance compared with non-treated cells.
Anti-fibrotic Effects of ONO-EF-345, a Specific Phosphodiesterase IV inhibitor, on Lung Fibroblasts
(2007-02-24) Hirata, Haruhiko; Hoshino, Shigenori; Inoue, Koji; Kashiwa, Yozo; Kawase, Ichiro; Kijima, Takashi; Kumagai, Toru; Osaki, Tadashi; Tachibana, Isao; Takimoto, Takayuki; Yanagita, Masahiko; Yano, Yukihiro; Yoshida, Mitsuhiro
Phosphodiesterase (PDE) IV inhibitors have been shown to inhibit various inflammatory reactions in pulmonary diseases such as bronchial asthma and chronic obstructive lung diseases (COPD). However, there have been no studies evaluating the effect of PDE IV inhibitors on airway fibrosis, which is a critical feature of airway remodeling in asthma and COPD. We therefore examined whether ONO-EF-345 (ONO), a PDE IV inhibitor, affected the function of lung fibroblasts. ONO suppressed TGF-ß-induced type I collagen (COL1) mRNA expression in lung fibroblasts and also inhibited TGF-ß-induced a- smooth muscle actin (SMA) protein expression. ONO did not affect Smad2 phosphorylation or Smad7 expression. However, ONO reduced JNK and p38 activation, which regulates TGF-ß-induced COL1 expression. These results indicate that PDE IV inhibitors exert anti-fibrotic effects through the JNK and/or p38 pathways.
Escherichia coli K88 Interaction with IgA Oligosaccharides
(2007-01-26) Acedo-Felix, Evelia; Ramos-Clamont M, Gabriela; Vázquez-Moreno, Luz; Winzerling, Joy
Diarrhea from enterotoxigenic Escherichia coli (E. coli) expressing the K88 fimbrial adhesin causes high morbidity and mortality among newborn and weaned piglets. K88 fimbrial adhesins are surface filaments with lectin activity that recognize specific glycoconjugates (glycoproteins or glycolipids) on the surface of intestinal cells. Carbohydrates that compete for adhesion attachment could serve as an alternative for disease prevention. In this study, IgA, IgG and IgM oligosaccharides were tested to inhibit the adhesion of E. coli K88 to piglet mucins. Immunoglobulins were isolated from porcine serum by hydrophobic interaction chromatography (HIC) and purified by affinity chromatography. In vitro K88 adhesin interacts specifically with IgA oligosaccharides, but not with carbohydrates of IgG or IgM. Also IgA oligosaccharides partially inhibit the adherence of K88 strain to porcine intestinal mucins.
DXS10079, DXS10074 and DXS10075
(2007-06-26) Augustin, C.; Dressler, J.; Edelmann, J.; Heidel, M.; Hering, S.; Rodig, H.; Szibor, R.
The number of established X-chromosomal STR markers suitable for forensic usage has risen continuously during recent years. The observation of X-chromosomal transmission lines can significantly contribute to the solving of complex kinship cases. The highly polymorphic tetranucleotide markers DXS10079, DXS10074 and DXS10075 are located within a 280 kb region at Xq12 and provide stable haplotypes. Most of these haplotypes occur at low frequencies in the German population, which would qualify this marker cluster as a useful tool in pedigree analysis. For routine use it is necessary to investigate the allele structure and check for variations in the repeat flanking region in samples of different ethnic populations. The information on SNP occurrence may help to minimise pitfalls caused by partial primer mismatching. We sequenced a variety of samples from Germans, Asians and Africans with respect to different STR alleles. For all three marker systems SNPs were detected in the repeat flanking regions. Some alleles found in the marker systems DXS10074 and DXS10075 exhibited typical repeat structures and SNP patterns found only in Africans and differing from Germans and Asians. The highest SNP diversity for DXS10079 was present in samples of all three ethnic groups. Further population data are needed to confirm this observation.
Reduced NK-Cell Activity in Patients with Metastatic Colon Cancer
(2007-01-15) Glanemann, Matthias; Guckelberger, Olaf; Nussler, Andreas K.; Nüssler, Natascha C.; Petzold, Martina; Stange, Barbara J.
Natural killer cells (NK-cells) are believed to play an essential role in the immune surveillance against tumors and infectious diseases. The role of NK-cells in colon cancer remains obscure, since increased as well as decreased percentages and/or activity of NK-cells in comparison to control patients have been reported. Percentage and cytolytic activity of NKcells in the peripheral blood were analyzed in 42 patients with colon cancer before surgery and one year thereafter in comparison to control patients with non-malignant diseases. Patients without distant metastasis at the time of diagnosis displayed a significantly increased percentage of NK-cells as well as sustained NK-cell activity in the peripheral blood prior to surgery when compared to control patients. In contrast, patients with metastatic disease at the time of diagnosis displayed significantly decreased NK-cell activity in the peripheral blood when compared to control patients. One year after surgery, patients who remained free of metastasis still displayed sustained NK-cell activity, whereas patients who developed metastasis presented with profoundly decreased levels of NK-cell activity. Further analysis of these patients revealed that patients who developed metastasis within the first year after surgery already displayed reduced NK-cell activity prior to curative colorectal surgery. These observations indicate that metastatic spread of colorectal cancer is associated with decreased NK-cell activity. It remains speculative whether decreased NK-cell activity precedes the development of metastasis and thus may help to identify patients with a high risk of rapid tumor progression following curative colorectal surgery.

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