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Sample records for aberrant crypt formation

  1. TRIBROMOMETHANE EXPOSURE AND DIETARY FOLATE DEFICIENCY IN THE FORMATION OF ABERRANT CRYPT FOCI IN THE COLONS OF F344/N RATS

    Science.gov (United States)

    TRIBROMOMETHANE EXPOSURE AND DIETARY FOLATE DEFICIENCY IN THE FORMATION OF ABERRANT CRYPT FOCI IN THE COLONS OF F344/N RATSDavid R. Geter', Tanya M. Moore', Michael H. George', Steve R. Kilburn', Gloria Huggins-Clark', James W. Allen', and Anthony B. DeAngelo' 'National H...

  2. Dietary Ziziphus jujuba Fruit Influence on Aberrant Crypt Formation and Blood Cells in Colitis-Associated Colorectal Cancer in Mice.

    Science.gov (United States)

    Periasamy, Srinivasan; Liu, Chung-Teng; Wu, Wang-Hung; Chien, Se-Ping; Liu, Ming-Yie

    2015-01-01

    Ziziphus jujuba (ZJ) fruit is rich in bioactive functional components such as polysaccharides, triterpenoid acid, flavonoids and oleamide. It has been commonly used in the treatment of various diseases including diabetes, digestive disorders, diarrhea, skin infections, liver and urinary complaints. However, dietary effects with regard to chemoprevention of colon cancer have not been studied. The present study was performed to evaluate the protective effects of dietary ZJ against colitis-associated colon carcinogenesis in azoxymethane (AOM)-dextran sodium sulphate (DSS)-treated mice. AOM was injected (10 mg/kg b.wt., i.p.) and three cycles of 2% DSS in drinking water for 7 days with 14 days of normal drinking water in-between were administered to induce colitis-associated colon cancer. ZJ fruit was supplemented into feed at levels of 5 and 10%. Dietary ZJ significantly attenuated aberrant crypt foci (ACF) formation and also decreased the progression of hyperplasia to dysplasia. In addition, it significantly reduced circulating white blood cells, lymphocytes, neutrophils, monocytes, eosinophils, basophils and platelets compared to colon cancer mice. We conclude that ZJ supplementation may delay the progression of colon cancer from hyperplasia to dysplasia and ultimately adenocarcinoma and cancer. In addition, it decreased circulating tumor-related leukocytes, main regulators of cancer inflammation. Dietary consumption of ZJ fruit attenuated the formation of ACF and delayed the progression of colon cancer.

  3. Inhibition of azoxymethane-induced aberrant crypt foci formation in rat colorectum by whole leaf Aloe arborescens Miller var. natalensis Berger.

    Science.gov (United States)

    Shimpo, K; Chihara, T; Beppu, H; Ida, C; Kaneko, T; Nagatsu, T; Kuzuya, H

    2001-12-01

    We examined the modifying effect of whole-leaf Aloe arborescens Miller var. natalensis Berger (designated as 'ALOE') on azoxymethane (AOM)-induced aberrant crypt foci (ACF), putative preneoplastic lesions, in the rat colorectum. Male F344 rats (4 weeks old) were fed the basal diet, or experimental diets containing 1% or 5% ALOE for 5 weeks. One week later, all rats except those in the vehicle-treated groups were injected s.c. with AOM (15 mg/kg, once weekly for 3 weeks). At 9 weeks of age, all the rats were killed, and the colorectum and liver were evaluated for ACF and cytosolic quinone reductase (QR; a phase 2 enzyme), respectively. In rats given AOM and ALOE (1% or 5% in diet) the numbers of ACF/colorectum, aberrant crypts/colorectum, aberrant crypts/focus and large ACF/colorectum were significantly decreased compared with those of rats given AOM alone (all p ALOE significantly increased cytosolic QR activity in the liver (p ALOE inhibited the development of AOM-induced ACF in the rat colorectum, with increased QR activity in the liver, and therefore suggested that ALOE might have a chemopreventive effect against colon carcinogenesis at least in the initiation stage. PMID:11746864

  4. Novel Combination of Prebiotics Galacto-Oligosaccharides and Inulin-Inhibited Aberrant Crypt Foci Formation and Biomarkers of Colon Cancer in Wistar Rats.

    Science.gov (United States)

    Qamar, Tahir Rasool; Syed, Fatima; Nasir, Muhammad; Rehman, Habib; Zahid, Muhammad Nauman; Liu, Rui Hai; Iqbal, Sanaullah

    2016-08-01

    The selectivity and beneficial effects of prebiotics are mainly dependent on composition and glycosidic linkage among monosaccharide units. This is the first study to use prebiotic galacto-oligosaccharides (GOS) that contains β-1,6 and β-1,3 glycosidic linkages and the novel combination of GOS and inulin in cancer prevention. The objective of the present study is to explore the role of novel GOS and inulin against various biomarkers of colorectal cancer (CRC) and the incidence of aberrant crypt foci (ACF) in a 1,2-dimethyl hydrazine dihydrochloride (DMH)-induced rodent model. Prebiotic treatments of combined GOS and inulin (57 mg each), as well as individual doses (GOS: 76-151 mg; inulin 114 mg), were given to DMH-treated animals for 16 weeks. Our data reveal the significant preventive effect of the GOS and inulin combination against the development of CRC. It was observed that inhibition of ACF formation (55.8%) was significantly (p ≤ 0.05) higher using the GOS and inulin combination than GOS (41.4%) and inulin (51.2%) treatments alone. This combination also rendered better results on short-chain fatty acids (SCFA) and bacterial enzymatic activities. Dose-dependent effects of prebiotic treatments were also observed on cecum and fecal bacterial enzymes and on SCFA. Thus, this study demonstrated that novel combination of GOS and inulin exhibited stronger preventive activity than their individual treatments alone, and can be a promising strategy for CRC chemoprevention.

  5. Novel Combination of Prebiotics Galacto-Oligosaccharides and Inulin-Inhibited Aberrant Crypt Foci Formation and Biomarkers of Colon Cancer in Wistar Rats

    Science.gov (United States)

    Qamar, Tahir Rasool; Syed, Fatima; Nasir, Muhammad; Rehman, Habib; Zahid, Muhammad Nauman; Liu, Rui Hai; Iqbal, Sanaullah

    2016-01-01

    The selectivity and beneficial effects of prebiotics are mainly dependent on composition and glycosidic linkage among monosaccharide units. This is the first study to use prebiotic galacto-oligosaccharides (GOS) that contains β-1,6 and β-1,3 glycosidic linkages and the novel combination of GOS and inulin in cancer prevention. The objective of the present study is to explore the role of novel GOS and inulin against various biomarkers of colorectal cancer (CRC) and the incidence of aberrant crypt foci (ACF) in a 1,2-dimethyl hydrazine dihydrochloride (DMH)-induced rodent model. Prebiotic treatments of combined GOS and inulin (57 mg each), as well as individual doses (GOS: 76–151 mg; inulin 114 mg), were given to DMH-treated animals for 16 weeks. Our data reveal the significant preventive effect of the GOS and inulin combination against the development of CRC. It was observed that inhibition of ACF formation (55.8%) was significantly (p ≤ 0.05) higher using the GOS and inulin combination than GOS (41.4%) and inulin (51.2%) treatments alone. This combination also rendered better results on short-chain fatty acids (SCFA) and bacterial enzymatic activities. Dose-dependent effects of prebiotic treatments were also observed on cecum and fecal bacterial enzymes and on SCFA. Thus, this study demonstrated that novel combination of GOS and inulin exhibited stronger preventive activity than their individual treatments alone, and can be a promising strategy for CRC chemoprevention. PMID:27490566

  6. Novel Combination of Prebiotics Galacto-Oligosaccharides and Inulin-Inhibited Aberrant Crypt Foci Formation and Biomarkers of Colon Cancer in Wistar Rats.

    Science.gov (United States)

    Qamar, Tahir Rasool; Syed, Fatima; Nasir, Muhammad; Rehman, Habib; Zahid, Muhammad Nauman; Liu, Rui Hai; Iqbal, Sanaullah

    2016-01-01

    The selectivity and beneficial effects of prebiotics are mainly dependent on composition and glycosidic linkage among monosaccharide units. This is the first study to use prebiotic galacto-oligosaccharides (GOS) that contains β-1,6 and β-1,3 glycosidic linkages and the novel combination of GOS and inulin in cancer prevention. The objective of the present study is to explore the role of novel GOS and inulin against various biomarkers of colorectal cancer (CRC) and the incidence of aberrant crypt foci (ACF) in a 1,2-dimethyl hydrazine dihydrochloride (DMH)-induced rodent model. Prebiotic treatments of combined GOS and inulin (57 mg each), as well as individual doses (GOS: 76-151 mg; inulin 114 mg), were given to DMH-treated animals for 16 weeks. Our data reveal the significant preventive effect of the GOS and inulin combination against the development of CRC. It was observed that inhibition of ACF formation (55.8%) was significantly (p ≤ 0.05) higher using the GOS and inulin combination than GOS (41.4%) and inulin (51.2%) treatments alone. This combination also rendered better results on short-chain fatty acids (SCFA) and bacterial enzymatic activities. Dose-dependent effects of prebiotic treatments were also observed on cecum and fecal bacterial enzymes and on SCFA. Thus, this study demonstrated that novel combination of GOS and inulin exhibited stronger preventive activity than their individual treatments alone, and can be a promising strategy for CRC chemoprevention. PMID:27490566

  7. Do aberrant crypt foci have predictive value for the occurrence of colorectal tumours? Potential of gene expression profiling in tumours

    NARCIS (Netherlands)

    Wijnands, M.V.W.; Erk, M.J. van; Doornbos, R.P.; Krul, C.A.M.; Woutersen, R.A.

    2004-01-01

    The effects of different dietary compounds on the formation of aberrant crypt foci (ACF) and colorectal tumours and on the expression of a selection of genes were studied in rats. Azoxymethane-treated male F344 rats were fed either a control diet or a diet containing 10% wheat bran (WB), 0.2% curcum

  8. Aberrant crypt foci as microscopic precursors of colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Lei Cheng; Mao-De Lai

    2003-01-01

    Since the first detection of aberrant crypt foci (ACF) in carcinogen-treated mice, there have been numerous studies focusing on these microscopically visible lesions both in rodents and in humans. ACF have been generally accepted as precancerous lesions in regard to histopathological characteristics, biochemical and immunohistochemical alterations, and genetic and epigenetic alterations. ACF show variable histological features, ranging from hyperplasia to dysplasia. ACF in human colon are more frequently located in the distal parts than in the proximal parts, which is in accordance with those in colorectal cancer (CRC). The immunohistochemical expressions of carcinoembryonic antigen (CEA), β-catenin, placental cadherin (P-cadherin),epithelial cadherin (E-cadherin), inducible nitric oxide synthase (iNOS), cyclooxygenase (COX-2), and P16INK4a are found to be altered. Genetic mutations of K-ras, APC and p53, and the epigenetic alterations of CpG island methylation of ACF have also been demonstrated. Genomic instabilities due to the defect of mismatch repair (MMR) system are detectable in ACF Two hypotheses have been proposed.One is the "dysplasia ACF-adenoma-carcinoma sequence",the other is "heteroplastic ACF-adenoma-carcinoma sequence". The malignant potential of ACF, especially dyspiastic ACF, makes it necessary to reveal the nature of these lesions, and to prevent CRC from the earliest possible stage. The technique of magnifying chromoscope makes it possible to detect "in vivo' ACF, which is beneficial to colon cancer research, identifying high-risk populations for CRC,and developing preventive procedures.

  9. Beta-escin inhibits colonic aberrant crypt foci formation in rats and regulates the cell cycle growth by inducing p21(waf1/cip1) in colon cancer cells.

    Science.gov (United States)

    Patlolla, Jagan M R; Raju, Jayadev; Swamy, Malisetty V; Rao, Chinthalapally V

    2006-06-01

    Extracts of Aesculus hippocastanum (horse chestnut) seed have been used in the treatment of chronic venous insufficiency, edema, and hemorrhoids. Most of the beneficial effects of horse chestnut are attributed to its principal component beta-escin or aescin. Recent studies suggest that beta-escin may possess anti-inflammatory, anti-hyaluronidase, and anti-histamine properties. We have evaluated the chemopreventive efficacy of dietary beta-escin on azoxymethane-induced colonic aberrant crypt foci (ACF). In addition, we analyzed the cell growth inhibitory effects and the induction of apoptosis in HT-29 human colon cancer cell line. To evaluate the inhibitory properties of beta-escin on colonic ACF, 7-week-old male F344 rats were fed experimental diets containing 0%, 0.025%, or 0.05% beta-escin. After 1 week, the rats received s.c. injections of azoxymethane (15 mg/kg body weight, once weekly for 2 weeks) or an equal volume of normal saline (vehicle). Rats were continued on respective experimental diets and sacrificed 8 weeks after the azoxymethane treatment. Colons were evaluated histopathologically for ACF. Administration of dietary 0.025% and 0.05% beta-escin significantly suppressed total colonic ACF formation up to approximately 40% (P < 0.001) and approximately 50% (P < 0.0001), respectively, when compared with control diet group. Importantly, rats fed beta-escin showed dose-dependent inhibition (approximately 49% to 65%, P < 0.0001) of foci containing four or more aberrant crypts. To understand the growth inhibitory effects, HT-29 human colon carcinoma cell lines were treated with various concentrations of beta-escin and analyzed by flow cytometry for apoptosis and cell cycle progression. Beta-escin treatment in HT-29 cells induced growth arrest at the G1-S phase, which was associated with the induction of the cyclin-dependent kinase inhibitor p21(WAF1/CIP1), and this correlated with reduced phosphorylation of retinoblastoma protein. Results also indicate that

  10. The ability of two cooked food mutagens to induce aberrant crypt foci in mice

    DEFF Research Database (Denmark)

    Kristiansen, E.; Meyer, Otto A.; Thorup, I.

    1997-01-01

    -amino-1-methyl-6-phenyl-imidazo[4,5-b]pyridine (PhIP) were used, To simulate the human exposure further, we chose a feeding regimen with continuous low IQ- and PhIP-doses, Throughout the study female mice were given diets with or without 0.03% IQ or 0.03% PhIP, Two additional groups were given...... azoxymethane (AOM) (5 mg/kg body weight) and 1,2-dimethylhydrazine dihydrochloride (DMH-2HCI) (20 mg/kg body weight), respectively, one dose a week for two weeks, Animals were killed after four and 10 weeks, After four weeks only the mice dosed with IQ and PhIP had aberrant crypt foci, A much higher number...... of aberrant crypt foci were found in the IQ mice (31.8 +/- 5.2) than in the PhIP mice (0.5 +/- 0.3), After 10 weeks aberrant crypt foci were found in all dosed groups, The IQ mice had significantly more (P less than or equal to 0.001) small and total aberrant crypt foci than the other groups, AOM and DMH...

  11. Aberrant crypt foci in the colo-rectal mucosa as reliable markers of tumor development

    DEFF Research Database (Denmark)

    Thorup, Inger

    The aim of the present thesis has been to evaluate a recently developed short term in vivo model, the aberrant crypt foci bioassay (ACF), for its ability to predict the development of colo-rectal tumors. Based on the knowledge obtained during the last decade, it can be stated that no simple...

  12. Probiotic Dahi containing Lactobacillus acidophilus and Bifidobacterium bifidum modulates the formation of aberrant crypt foci, mucin-depleted foci, and cell proliferation on 1,2-dimethylhydrazine-induced colorectal carcinogenesis in Wistar rats.

    Science.gov (United States)

    Mohania, Dheeraj; Kansal, Vinod K; Kruzliak, Peter; Kumari, Archana

    2014-08-01

    Aberrant crypt foci (ACF) and mucin-depleted foci (MDF) are pre-neoplastic lesions identified in the colon of carcinogen-treated rodents and in humans at high risk for colon cancer. The present study was carried out to divulge the protective potential of the probiotic Dahi containing Lactobacillus acidophilus LaVK2 and Bifidobacterium bifidum BbVK3 alone or in combination with piroxicam (PXC) on the development of early biomarkers of colorectal carcinogenesis in male Wistar rats administered 1,2-dimethylhydrazine (DMH). DMH was injected subcutaneously at the rate of 40 mg/kg body weight per animal twice a week for 2 weeks. A total of 120 male Wistar rats were randomly allocated to five groups, each group having 24 animals. The rats were fed with buffalo milk or probiotic supplement (20 grams) alone or as an adjunct with PXC in addition to a basal diet ad libitum for 32 weeks. Group I was offered buffalo milk (BM) and served as the control group. Group II was administered DMH along with BM and served as the DMH-control group; group III was administered BM-DMH-PXC, in which besides administering BM-DMH, PXC was also offered. Group IV was offered probiotic LaBb Dahi and DMH, and group V was offered both probiotic LaBb Dahi and PXC along with DMH. The rats were euthanized at the 8(th), 16(th), and 32(nd) week of the experiment and examined for development of ACF, aberrant crypts per ACF (AC/ACF), mucin-depleted foci (MDF), large MDF, and proliferating cell nuclear antigen (PCNA) labeling index. Administration of DMH in rats induced pre-neoplastic lesions (ACF and MDF) and increased the PCNA index in colorectal tissue. A significant (pprobiotic LaBb Dahi group compared with the DMH control group. Feeding rats with LaBb Dahi or treatment with PXC diminished the initiation and progression of DMH-induced pre-neoplastic lesions and the PCNA index, and treatment with LaBb Dahi and PXC combined was significantly more effective. The dietary intervention of probiotics and PXC

  13. Aberrant Crypt Foci: The Case for Inclusion as a Biomarker for Colon Cancer

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    Jay Morris

    2010-09-01

    Full Text Available Aberrant crypt foci (ACF are one of the earliest histopathological manifestations of colon cancer. In this review, we critically present the molecular, cellular, histopathological, and chemopreventive evidence that ACF are relevant biomarkers for colon cancer. The laboratory and clinical evidence are highly suggestive that ACF are in the pathway leading to colon cancer, but not all ACF will do so. The possible fate and outcome of ACF in the progression toward colon cancer may be dependent on a number of features that define their predictive power for the prevention or progression of cancer.

  14. Chromoendoscopy with a Standard-Resolution Colonoscope for Evaluation of Rectal Aberrant Crypt Foci.

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    Marek Kowalczyk

    Full Text Available Colorectal cancer (CRC is the second most common cause of death worldwide. According to the theory by Vogelstein, colorectal carcinogenesis involves a series of successive changes in the normal colonic mucosa, starting with excessive proliferation and focal disorders of intestinal crypts, followed by adenoma and its subsequent malignant transformation. The first identifiable changes in CRC carcinogenesis are aberrant crypt foci (ACF. ACF are invisible during routine colonoscopy yet are well identifiable in chromoendoscopy using methylene blue or indigo carmine. High-resolution colonoscopes are used for assessment of ACF. The aim of the present study was to evaluate the usefulness of standard-resolution colonoscopy for identification of rectal ACF. The following parameters were evaluated: duration of chromoendoscopy of a given rectal segment, type of ACF, sensitivity and specificity of endoscopy combined with histopathological evaluation. The mean duration of colonoscopy and chromoendoscopy was 26.8 min. In the study population, typical ACF were found in 73 patients (p = 0.489, hyperplastic ACF in 49 (p = 0.328, and dysplastic ACF in 16 patients (p = 0.107. Mixed ACF were observed in 11 individuals (p = 0.073. The sensitivity of the method was found to be 0.96 whereas its specificity 0.99. Identification of rectal ACF using standard-resolution colonoscopy combined with rectal mucosa staining with 0.25% methylene blue is characterised by high sensitivity and specificity.

  15. Eicosapentaenoic acid (EPA) efficacy for colorectal aberrant crypt foci (ACF): a double-blind randomized controlled trial

    International Nuclear Information System (INIS)

    Colorectal cancer (CRC) is one of the most commonly occurring neoplasms and a leading cause of cancer death worldwide, and new preventive strategies are needed to lower the burden of this disease. Eicosapentaenoic acid (EPA), the omega-3 polyunsaturated fatty acid that is widely used in the treatment of hyperlipidemia and prevention of cardiovascular disease, has recently been suggested to have a suppressive effect on tumorigenesis and cancer cell growth. In CRC chemoprevention trials, in general, the incidence of polyps or of the cancer itself is set as the study endpoint. Although the incidence rate of CRC would be the most reliable endpoint, use of this endpoint would be unsuitable for chemoprevention trials, because of the relatively low occurrence rate of CRC in the general population and the long-term observation period that it would necessitate. Moreover, there is an ethical problem in conducting long-term trials to determine whether a test drug might be effective or harmful. Aberrant crypt foci (ACF), defined as lesions containing crypts that are larger in diameter and stain more darkly with methylene blue than normal crypts, are considered as a reliable surrogate biomarker of CRC. Thus, we devised a prospective randomized controlled trial as a preliminary study prior to a CRC chemoprevention trial to evaluate the chemopreventive effect of EPA against colorectal ACF formation and the safety of this drug, in patients scheduled for polypectomy. This study is a multicenter, double-blind, placebo-controlled, randomized controlled trial to be conducted in patients with both colorectal ACF and colorectal polyps scheduled for polypectomy. Eligible patients shall be recruited for the study and the number of ACF in the rectum counted at the baseline colonoscopy. Then, the participants shall be allocated randomly to either one of two groups, the EPA group and the placebo group. Patients in the EPA group shall receive oral 900-mg EPA capsules thrice daily (total daily

  16. Eicosapentaenoic acid (EPA efficacy for colorectal aberrant crypt foci (ACF: a double-blind randomized controlled trial

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    Higurashi Takuma

    2012-09-01

    Full Text Available Abstract Background Colorectal cancer (CRC is one of the most commonly occurring neoplasms and a leading cause of cancer death worldwide, and new preventive strategies are needed to lower the burden of this disease. Eicosapentaenoic acid (EPA, the omega-3 polyunsaturated fatty acid that is widely used in the treatment of hyperlipidemia and prevention of cardiovascular disease, has recently been suggested to have a suppressive effect on tumorigenesis and cancer cell growth. In CRC chemoprevention trials, in general, the incidence of polyps or of the cancer itself is set as the study endpoint. Although the incidence rate of CRC would be the most reliable endpoint, use of this endpoint would be unsuitable for chemoprevention trials, because of the relatively low occurrence rate of CRC in the general population and the long-term observation period that it would necessitate. Moreover, there is an ethical problem in conducting long-term trials to determine whether a test drug might be effective or harmful. Aberrant crypt foci (ACF, defined as lesions containing crypts that are larger in diameter and stain more darkly with methylene blue than normal crypts, are considered as a reliable surrogate biomarker of CRC. Thus, we devised a prospective randomized controlled trial as a preliminary study prior to a CRC chemoprevention trial to evaluate the chemopreventive effect of EPA against colorectal ACF formation and the safety of this drug, in patients scheduled for polypectomy. Methods This study is a multicenter, double-blind, placebo-controlled, randomized controlled trial to be conducted in patients with both colorectal ACF and colorectal polyps scheduled for polypectomy. Eligible patients shall be recruited for the study and the number of ACF in the rectum counted at the baseline colonoscopy. Then, the participants shall be allocated randomly to either one of two groups, the EPA group and the placebo group. Patients in the EPA group shall receive oral

  17. Evaluation of Blueberry Juice in Mouse Azoxymethane-Induced Aberrant Crypts and Oxidative Damage

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    Isela Álvarez-González

    2014-01-01

    Full Text Available Blueberry is a plant with a number of nutritional and biomedical capabilities. In the present study we initially evaluated the capacity of its juice (BJ to inhibit the number of aberrant crypts (AC induced with azoxymethane (AOM in mouse. BJ was administered daily by the oral route to three groups of animals during four weeks (1.6, 4.1, and 15.0 μL/g, respectively, while AOM (10 mg/kg was intraperitoneally injected to the mentioned groups, twice a week, in weeks two and three of the assay. We also included two control groups of mice, one administered distilled water and the other the high dose of BJ. A significant increase of AC was observed in the AOM treated animals, and a mean protection of 75.6% was determined with the two low doses of BJ tested; however, the high dose of the juice administered together with AOM increased the number of crypts more than four times the value observed in animals administered only AOM. Furthermore, we determined the antioxidant potential of BJ with an ex vivo DPPH assay and found a dose-dependent decrease with a mean of 19.5%. We also determined the DNA oxidation/antioxidation by identifying 8-hydroxy-2′-deoxyguanosine adducts and found a mean decrease of 44.3% with the BJ administration with respect to the level induced by AOM. Our results show a complex differential effect of BJ related to the tested doses, opening the need to further evaluate a number of factors so as to determine the possibility of a cocarcinogenic potential.

  18. Azoxymethane-induced rat aberrant crypt foci: Relevance in studying chemoprevention of colon cancer

    Institute of Scientific and Technical Information of China (English)

    Jayadev Raju

    2008-01-01

    The pathogenesis of colon cancer involves sequential and multistep progression of epithelial cells initiated to a cancerous state with defined precancerous intermediaries.Aberrant crypt foci (ACF) represent the earliest identifiable intermediate precancerous lesions during colon carcinogenesis in both laboratory animals and humans.ACF are easily induced by colon-specific carcinogens in rodents and can be used to learn more about the process of colon carcinogenesis.For over two decades,since its first discovery,azoxymethane(AOM)-induced rodent ACF have served as surrogate biomarkers in the screening of various anticarcinogens and carcinogens.Several dietary constituents and phytochemicals have been tested for their colon cancer chemopreventive efficacy using the ACF system.There has been substantial effort in defining and refining ACF in terms of understanding their molecular make-up,and extensive research in this field is currently in progress.In chemoprevention studies,AOM-induced rat ACF have been very successful as biomarkers,and have provided several standardized analyses of data.There have been several studies that have reported that ACF data do not correlate to actual colon tumor outcome,however,and hence there has been an ambiguity about their role as biomarkers.The scope of this mini-review is to provide valuable insights and limitations of AOM-induced rat ACF as biomarkers in colon cancer chemoprevention studies.The role of the dynamics and biological heterogeneity of ACF is critical in understanding them as biomarkers in chemoprevention studies.

  19. The chemopreventive potential of Curcuma purpurascens rhizome in reducing azoxymethane-induced aberrant crypt foci in rats.

    Science.gov (United States)

    Rouhollahi, Elham; Moghadamtousi, Soheil Zorofchian; Al-Henhena, Nawal; Kunasegaran, Thubasni; Hasanpourghadi, Mohadeseh; Looi, Chung Yeng; Abd Malek, Sri Nurestri; Awang, Khalijah; Abdulla, Mahmood Ameen; Mohamed, Zahurin

    2015-01-01

    Curcuma purpurascens BI. rhizome, a member of the Zingiberaceae family, is a popular spice in Indonesia that is traditionally used in assorted remedies. Dichloromethane extract of C. purpurascens BI. rhizome (DECPR) has previously been shown to have an apoptosis-inducing effect on colon cancer cells. In the present study, we examined the potential of DECPR to prevent colon cancer development in rats treated with azoxymethane (AOM) (15 mg/kg) by determining the percentage inhibition in incidence of aberrant crypt foci (ACF). Starting from the day immediately after AOM treatment, three groups of rats were orally administered once a day for 2 months either 10% Tween 20 (5 mL/kg, cancer control), DECPR (250 mg/kg, low dose), or DECPR (500 mg/kg, high dose). Meanwhile, the control group was intraperitoneally injected with 5-fluorouracil (35 mg/kg) for 5 consecutive days. After euthanizing the rats, the number of ACF was enumerated in colon tissues. Bax, Bcl-2, and proliferating cell nuclear antigen (PCNA) protein expressions were examined using immunohistochemical and Western blot analyses. Antioxidant enzymatic activity was measured in colon tissue homogenates and associated with malondialdehyde level. The percentage inhibition of ACF was 56.04% and 68.68% in the low- and high-dose DECPR-treated groups, respectively. The ACF inhibition in the treatment control group was 74.17%. Results revealed that DECPR exposure at both doses significantly decreased AOM-induced ACF formation, which was accompanied by reduced expression of PCNA. Upregulation of Bax and downregulation of Bcl-2 suggested the involvement of apoptosis in the chemopreventive effect of DECPR. In addition, the oxidative stress resulting from AOM treatment was significantly attenuated after administration of DECPR, which was shown by the elevated antioxidant enzymatic activity and reduced malondialdehyde level. Taken together, the present data clearly indicate that DECPR significantly inhibits ACF formation

  20. DNA damage and aberrant crypt foci as putative biomarkers to evaluate the chemopreventive effect of annatto (Bixa orellana L.) in rat colon carcinogenesis.

    Science.gov (United States)

    Agner, Aniele R; Bazo, Ana P; Ribeiro, Lúcia R; Salvadori, Daisy M F

    2005-04-01

    Chemoprevention opens new perspectives in the prevention of cancer and other degenerative diseases. Use of target-organ biological models at the histological and genetic levels can markedly facilitate the identification of such potential chemopreventive agents. Colon cancer is one of the highest incidence rates throughout the world and some evidences have indicated carotenoids as possible agents that decrease the risk of colorectal cancer. In the present study, we evaluate the activity of annatto (Bixa orellana L.), a natural food colorant rich in carotenoid, on the formation of aberrant crypt foci (ACF) induced by dimethylhydrazine (DMH) in rat colon. Further, we investigate, the effect of annatto on DMH-induced DNA damage, by the comet assay. Male Wistar rats were given s.c. injections of DMH (40 mg/kg body wt.) twice a week for 2 weeks to induce ACF. They also received experimental diets containing annatto at 20, 200 or 1000 ppm for five 5 weeks before (pre-treatment), or 10 weeks after (post-treatment) DMH treatment. In both protocols the rats were sacrificed on week 15th. For the comet assay, the animals were fed with the same experimental diets for 2 weeks. Four hours before the sacrifice, the animals received an s.c. injection of DMH (40 mg/kg body wt.). Under such conditions, dietary administration of 1000 ppm annatto neither induce DNA damage in blood and colon cells nor aberrant crypt foci in rat distal colon. Conversely, annatto was successful in inhibiting the number of crypts/colon (animal), but not in the incidence of DMH-induced ACF, mainly when administered after DMH. However, no antigenotoxic effect was observed in colon cells. These findings suggest possible chemopreventive effects of annatto through their modulation of the cryptal cell proliferation but not at the initiation stage of colon carcinogenesis. PMID:15781219

  1. Influence of Different Diets on Development of DMH-Induced Aberrant Crypt Foci and Colon Tumor Incidence in Wistar Rats

    DEFF Research Database (Denmark)

    Kristiansen, E.; Thorup, I.; Meyer, Otto A.

    1995-01-01

    The present study was undertaken to investigate certain dietary factors known to affect the development of colon cancer for their ability to modulate aberrant crypt foci (ACI;). Male Wistar rats were initiated with oral noses of dimethylhydrazine dihydrochloride (DMH-2HCl, 20 mg/kg body wt) once.......05) in the total number of ACF and number of small and medium ACF was observed. The values of large and extra-large foci reflected the same effect of diets on ACF. The results indicate that tumors in the group fed the diet high in refined carbohydrates were more prominent and occurred with a higher incidence...

  2. IGF-II transgenic mice display increased aberrant colon crypt multiplicity and tumor volume after 1,2-dimethylhydrazine treatment

    Directory of Open Access Journals (Sweden)

    Oesterle Doris

    2006-01-01

    Full Text Available Abstract In colorectal cancer insulin-like growth factor II (IGF-II is frequently overexpressed. To evaluate, whether IGF-II affects different stages of tumorigenesis, we induced neoplastic alterations in the colon of wild-type and IGF-II transgenic mice using 1,2-dimethylhydrazine (DMH. Aberrant crypt foci (ACF served as markers of early lesions in the colonic mucosa, whereas adenomas and carcinomas characterized the endpoints of tumor development. DMH-treatment led initially to significantly more ACF in IGF-II transgenic than in wild-type mice. This increase in ACF was especially prominent for those consisting of ≥three aberrant crypts (AC. Nevertheless, adenomas and adenocarcinomas of the colon, present after 34 weeks in both genetic groups, were not found at different frequency. Tumor volumes, however, were significantly higher in IGF-II transgenic mice and correlated with serum IGF-II levels. Immunohistochemical staining for markers of proliferation and apoptosis revealed increased cell proliferation rates in tumors of IGF-II transgenic mice without significant affection of apoptosis. Increased proliferation was accompanied by elevated localization of β-catenin in the cytosol and cell nuclei and reduced appearance at the inner plasma membrane. In conclusion, we provide evidence that IGF-II, via activation of the β-catenin signaling cascade, promotes growth of ACF and tumors without affecting tumor numbers.

  3. Oral 5-fluorouracil colon-specific delivery through in vivo pellet coating for colon cancer and aberrant crypt foci treatment.

    Science.gov (United States)

    Bose, A; Elyagoby, A; Wong, T W

    2014-07-01

    In situ coating of 5-fluorouracil pellets by ethylcellulose and pectin powder mixture (8:3 weight ratio) in capsule at simulated gastrointestinal media provides colon-specific drug release in vitro. This study probes into pharmacodynamic and pharmacokinetic profiles of intra-capsular pellets coated in vivo in rats with reference to their site-specific drug release outcomes. The pellets were prepared by extrusion-spheronization technique. In vitro drug content, drug release, in vivo pharmacokinetics, local colonic drug content, tumor, aberrant crypt foci, systemic hematology and clinical chemistry profiles of coated and uncoated pellets were examined against unprocessed drug. In vivo pellet coating led to reduced drug bioavailability and enhanced drug accumulation at colon (179.13 μg 5-FU/g rat colon content vs 4.66 μg/g of conventional in vitro film-coated pellets at 15 mg/kg dose). The in vivo coated pellets reduced tumor number and size, through reforming tubular epithelium with basement membrane and restricting expression of cancer from adenoma to adenocarcinoma. Unlike uncoated pellets and unprocessed drug, the coated pellets eliminated aberrant crypt foci which represented a putative preneoplastic lesion in colon cancer. They did not inflict additional systemic toxicity. In vivo pellet coating to orally target 5-fluorouracil delivery at cancerous colon is a feasible therapeutic treatment approach.

  4. Chemopreventive effect of myrtenal on bacterial enzyme activity and the development of 1,2-dimethyl hydrazine-induced aberrant crypt foci in Wistar Rats

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    Lokesh Kumar Booupathy

    2016-01-01

    Full Text Available Colon cancer remains as a serious health problem around the world despite advances in diagnosis and treatment. Dietary fibers are considered to reduce the risk of colon cancer as they are converted to short chain fatty acids by the presence of anaerobic bacteria in the intestine, but imbalanced diet and high fat consumption may promote tumor formation at different sites, including the large bowel via increased bacterial enzymes activity. The present study was conducted to characterize the inhibitory action of myrtenal on bacterial enzymes and aberrant crypt foci (ACF. Experimental colon carcinogenesis induced by 1,2-dimethylhydrazine is histologically, morphologically, and anatomically similar to human colonic epithelial neoplasm. Discrete microscopic mucosal lesions such as ACF and malignant tumors function as important biomarkers in the diagnosis of colon cancer. Methylene blue staining was carried out to visualize the impact of 1,2-dimethylhydrazine and myrtenal. Myrtenal-treated animals showed decreased levels of bacterial enzymes such as β-glucuronidase, β-glucosidase, and mucinase. Characteristic changes in the colon were noticed by inhibiting ACF formation in the colon. In conclusion, treatment with myrtenal provided altered pathophysiological condition in colon cancer-bearing animals with evidence of decreased crypt multiplicity and tumor progression.

  5. The chemopreventive potential of Curcuma purpurascens rhizome in reducing azoxymethane-induced aberrant crypt foci in rats

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    Rouhollahi E

    2015-07-01

    Full Text Available Elham Rouhollahi,1 Soheil Zorofchian Moghadamtousi,2 Nawal Al-Henhena,3 Thubasni Kunasegaran,1 Mohadeseh Hasanpourghadi,4 Chung Yeng Looi,4 Sri Nurestri Abd Malek,2 Khalijah Awang,5 Mahmood Ameen Abdulla,3 Zahurin Mohamed1 1Pharmacogenomics Laboratory, Department of Pharmacology, Faculty of Medicine, 2Institute of Biological Sciences, Faculty of Science, 3Department of Biomedical Science, 4Cell Biology and Drug Discovery Laboratory, Department of Pharmacology, Faculty of Medicine, 5Department of Chemistry, University of Malaya, Kuala Lumpur, Malaysia Abstract: Curcuma purpurascens BI. rhizome, a member of the Zingiberaceae family, is a popular spice in Indonesia that is traditionally used in assorted remedies. Dichloromethane extract of C. purpurascens BI. rhizome (DECPR has previously been shown to have an apoptosis-inducing effect on colon cancer cells. In the present study, we examined the potential of DECPR to prevent colon cancer development in rats treated with azoxymethane (AOM (15 mg/kg by determining the percentage inhibition in incidence of aberrant crypt foci (ACF. Starting from the day immediately after AOM treatment, three groups of rats were orally administered once a day for 2 months either 10% Tween 20 (5 mL/kg, cancer control, DECPR (250 mg/kg, low dose, or DECPR (500 mg/kg, high dose. Meanwhile, the control group was intraperitoneally injected with 5-fluorouracil (35 mg/kg for 5 consecutive days. After euthanizing the rats, the number of ACF was enumerated in colon tissues. Bax, Bcl-2, and proliferating cell nuclear antigen (PCNA protein expressions were examined using immunohistochemical and Western blot analyses. Antioxidant enzymatic activity was measured in colon tissue homogenates and associated with malondialdehyde level. The percentage inhibition of ACF was 56.04% and 68.68% in the low- and high-dose DECPR-treated groups, respectively. The ACF inhibition in the treatment control group was 74.17%. Results revealed that

  6. THE EFFECTS OF A HIGH ANIMAL FAT DIET ON THE INDUCTION OF ABERRANT CRYPT FOCI IN THE COLONS OF MALE F344/N RATS EXPOSED TO TRIHALOMETHANES IN THE DRINKING WATER

    Science.gov (United States)

    The Effects of a High Animal Fat Diet on the Induction of Aberrant Crypt Foci in the Colons of Male F344/N Rats Exposed to Trihalomethanes in the Drinking WaterAbstract Aberrant crypt foci (ACF), identified as the putative precursor lesion in the development of co...

  7. Polyethylene glycol, unique among laxatives, suppresses aberrant crypt foci, by elimination of cells.

    OpenAIRE

    Taché, Sylviane; Parnaud, Géraldine; van Beek, Erik; Corpet, Denis E

    2006-01-01

    International audience OBJECTIVE: Polyethylene glycol (PEG), an osmotic laxative, is a potent inhibitor of colon cancer in rats. In a search for the underling mechanisms, the hypothesis that fecal bulking and moisture decrease colon carcinogenesis was tested. We also investigated the PEG effects on crypt cells in vivo. MATERIAL AND METHODS: Fischer 344 rats (n=272) were injected with the colon carcinogen, azoxymethane. They were then randomized to a standard AIN76 diet containing one of 19...

  8. Dark Aberrant Crypt Foci with activated Wnt pathway are related to tumorigenesis in the colon of AOM-treated rat

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    Lin Chen

    2008-08-01

    Full Text Available Abstract Background To evaluate the relationship between Aberrant Crypt Foci (ACF and tumorigenesis, we observed the sequential development from ACF to tumor in the colon of azoxymethane-exposed wistar rats. Methods Sixty wistar rats were sacrificed at different time points after exposure to azoxymethane and the colons were stained with methylene blue for stereomicroscopic analysis. Results We found two types of early lesions: classic ACF and dark ACF. Dark ACF were characterized by dark blue staining, mildly enlarged or small compressed crypts that are not elevated from the surrounding epithelium. Large dark ACF and nascent tumors displayed the same surface morphology. Furthermore, dark ACF grew significantly faster than classic ACF and showed dysplasia without hyperplasia. In contrast, classic ACF showed hyperplasia without dysplasia. Dark ACF has significant higher expression rate of β-catenin (100% and MMP-7 (81.82% compared with the expression of β-catenin and MMP-7 in classic ACF (4.84% and 7.87%, respectively. Conclusion Our data indicated that dark ACF is closely related to tumorigenesis while classic ACF is not. Furthermore, Wnt signal pathway was activated during the early period of dark ACF.

  9. Effects of high fat fish oil and high fat corn oil diets on initiation of AOM-induced colonic aberrant crypt foci in male F344 rats

    NARCIS (Netherlands)

    Dommels, Y.E.M.; Heemskerk, S.; Berg, H. van den; Alink, G.M.; Bladeren, P.J. van; Ommen, B. van

    2003-01-01

    Modulating effects of high fat fish oil (HFFO) and high fat corn oil (HFCO) diets on azoxymethane (AOM)-induced colonic aberrant crypt foci (ACF) were studied in male F344 rats following 8 weeks of dietary treatment. The incidence of AOM-induced ACF was significantly lower in the proximal colon of r

  10. Effect of a hyperlipidic diet rich in omegas 3, 6 and 9 on aberrant crypt formation in rat colonic mucosa Efeito de uma dieta hiperlipídica rica em ômegas 3, 6 e 9 na formação de criptas aberrantes em mucosa cólica de ratos

    Directory of Open Access Journals (Sweden)

    Idália Maria Brasil Burlamaqui

    2012-01-01

    Full Text Available PURPOSE: To determine whether a hypercaloric and hyperlipidic diet enriched with polyunsaturated fatty acids influences the formation of aberrant crypt foci (ACF in colonic mucosa of Wistar rats treated with azoxymethane (AOM. METHODS: At eight weeks of life, the rats were assigned to four groups: Group I―standard diet (STD not treated with AOM; Group II―hypercaloric and hyperlipidic diet (FED, not treated with AOM; Group III―STD, treated with AOM; Group IV―FED, treated with AOM. At 16 weeks, the animals were injected intraperitoneal with 0.9% saline solution (Group I and II or AOM at 15mg/Kg (Groups III and IV once a week for two weeks. Fifteen weeks later, the animals were euthanized. RESULTS: FED promoted weight gain in Groups II and IV compared to Groups I and III, respectively. The groups did not differ with regard to the total number of ACF. The Chi-square test revealed no predominance of the presence of foci with OBJETIVO: Determinar se uma dieta hipercalórica, hiperlipídica, rica em ácidos graxos poliinsaturados (FED tem influência na formação de focos de cripta aberrante (FCA em mucosa cólica de ratos Wistar expostos ao azoximetano (AOM. MÉTODOS: Com oito semanas de vida, os ratos foram distribuídos em quatro grupos: Grupo I: Dieta padrão (SD sem AOM; Grupo II: FED, sem AOM; Grupo III: SD, com AOM; Grupo IV: FED com AOM. Com 16 semanas, os animais dos grupos I e II receberam injeções intraperitoneais de solução salina 0,9%, enquanto os dos grupos III e IV receberam AOM na dose de 15mg/Kg de peso, 1 vez por semana por duas semanas. Quinze semanas após, os animais foram mortos. RESULTADOS: FED promoveu aumento de peso nos grupos II e IV em relação aos grupos I e III. Não houve aumento significante no número total de FCA entre os grupos. Em relação à multiplicidade das criptas por FCA, o teste do qui-quadrado mostrou que não houve predominância da presença <4 criptas por foco. Contudo, focos ≥5 criptas

  11. Aberrant crypt foci and colon cancer: comparison between a short- and medium-term bioassay for colon carcinogenesis using dimethylhydrazine in Wistar rats

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    Rodrigues M.A.M.

    2002-01-01

    Full Text Available Aberrant crypt foci (ACF in the colon of carcinogen-treated rodents are considered to be the earliest hallmark of colon carcinogenesis. In the present study the relationship between a short-term (4 weeks and medium-term (30 weeks assay was assessed in a model of colon carcinogenesis induced by dimethylhydrazine (DMH in the rat. Six-week-old male Wistar rats were given subcutaneous injections of DMH (40 mg/kg twice a week for 2 weeks and killed at the end of the 4th or 30th week. ACF were scored for number, distribution pattern along the colon and crypt multiplicity in 0.1% methylene-blue whole-mount preparations. ACF were distinguished from normal crypts by their larger size and elliptical shape. The incidence, distribution and morphology of colon tumors were recorded. The majority of ACF were present in the middle and distal colon of DMH-treated rats and their number increased with time. By the 4th week, 91.5% ACF were composed of one or two crypts and 8.5% had three or more crypts, while by the 30th week 46.9% ACF had three or more crypts. Thus, a progression of ACF consisting of multiple crypts was observed from the 4th to the 30th week. Nine well-differentiated adenocarcinomas were found in 10 rats by the 30th week. Seven tumors were located in the distal colon and two in the middle colon. No tumor was found in the proximal colon. The present data indicate that induction of ACF by DMH in the short-term (4 weeks assay was correlated with development of well-differentiated adenocarcinomas in the medium-term (30 weeks assay.

  12. Effect of vanadium on colonic aberrant crypt foci induced in rats by 1,2 Dimethyl hydrazine

    Institute of Scientific and Technical Information of China (English)

    P Suresh Kanna; CB Mahendrakumar; T Chakraborty; P Hemalatha; Pratik Banerjee; M Chatterjee

    2003-01-01

    AIM: To investigate the chemo preventive effects of vanadium on rat colorectal carcinogenesis induced by 1,2-dimethylhydrazine (DMH).METHODS: Male Sprague-Dawley Rats were randomly divided into four groups. Rats in Group A received saline vehicle alone for 16 weeks. Rats in Group B were given DMH injection once a week intraperitoneally for 16 weeks;rats in Group C, with the same DMH treatment as in the Group B, but received 0.5-ppm vanadium in the form ammonium monovanadate ad libitum in drinking water. Rats in the Group D received vanadium alone as in the Group C without DMH injection.RESULTS: Aberrant crypt foci (ACF) were formed in animals in DMH-treated groups at the end of week 16.Compared to DMH group, vanadium treated group had less ACF (P<0.001). At the end of week 32, all rats in DMH group developed large intestinal tumors. Rats treated with vanadium contained significantly few colonic adenomas and carcinomas (P<0.05) compared to rats administered DMH only. In addition, a significant reduction (P<0.05) in colon tumor burden (sum of tumor sizes per animal) was also evident in animals of Group C when compared to those in rats of carcinogen control Group B. The results also showed that vanadium significantly lowered PCNA index in ACF (P<0.005). Furthermore, vanadium supplementation also elevated liver GST and Cyt P-450 activities (P<0.001 and P<0.02, respectively).CONCLUSION: Vanadium in the form of ammonium monovanadate supplemented in drinking water ad libitum has been found to be highly effective in reducing tumor incidence and preneoplastic foci on DMH-induced colorectal carcinogenesis. These findings suggest that vanadium administration can suppress colon carcinogenesis in rats.

  13. The influence of simple sugars and starch given during pre- or post-initiation on aberrant crypt foci in rat colon

    DEFF Research Database (Denmark)

    Poulsen, Morten; Mølck, Anne-Marie; Thorup, Inger;

    2001-01-01

    The aim of the present study was to investigate the enhancing effect of dietary sugar on the development of aberrant crypt foci (ACF) in male F344 rats initiated with azoxymethane (AOM). The potential role of sugar as either a co-initiator or a promoter was investigated by giving diets high...... was seen. The level of oxidative stress in the cytosol from the proximal colon and colonic glutathione transferase and quinone reductase was not affected by the sugar treatments. The overall results from this study show that sucrose and dextrin enhance the number of preneoplastic lesions in AOM...

  14. Different effects of short- and long-chained fructans on large intestinal physiology and carcinogen-induced aberrant crypt foci in rats

    DEFF Research Database (Denmark)

    Poulsen, Morten; Molck, Anne-Marie; Jacobsen, Bodil Lund

    2002-01-01

    the development of ACF: microflora, short-chain fatty acids, pH, and cell proliferation. A 3-wk pretreatment period with both fructans was included. Feeding the long-chained fructan (5% or 15%) significantly inhibited the numbers of small and total ACF after 5 and 10 wk. The short-chained fructan (15......-type fructan on 1,2-dimethylhydrazine dihydrochloride-induced aberrant crypt foci (ACF) in the rat colon. In addition, the present study investigated the influence of chain length, dietary level (5% or 15%), and duration of feeding (5 or 10 wk) on the following intestinal parameters supposed to be involved in...

  15. Hydrolysed inulin alleviates the azoxymethane-induced preneoplastic aberrant crypt foci by altering selected intestinal microbiota in Sprague-Dawley rats.

    Science.gov (United States)

    Pattananandecha, Thanawat; Sirilun, Sasithorn; Duangjitcharoen, Yodsawee; Sivamaruthi, Bhagavathi Sundaram; Suwannalert, Prasit; Peerajan, Sartjin; Chaiyasut, Chaiyavat

    2016-09-01

    Context Inulin, a non-digestible carbohydrate isolated from Helianthus tuberosus L. (Asteraceae), has been shown to alter the gut beneficial bacteria including Lactobacillus spp. and Bifidobacteria. Inulin also influences the activities of intestinal microbiota that could prevent the colon cancer development. Objective This study determines the effect of hydrolysed inulin with different degrees of polymerisation on alteration of intestinal microbiota and their activities on azoxymethane (AOM)-induced preneoplastic aberrant crypt foci (ACF) in rats. Materials and methods Seventy-two male Sprague-Dawley rats were randomly divided into six groups (three control and three AOM-treated groups) and the animal were fed with either a normal diet or diet containing 10% of long-chain inulin (InuL) or short-chain inulin (InuS), respectively, for 17 weeks. Colon cancer was induced in rats by injecting AOM subcutaneously at the 8th and 9th week of the study period. At the end of the experiment, cecal contents of rats were examined for selected microbiota, organic acids, putrefactive compounds and microbial enzymes. ACF formation was microscopically examined. Results The inulin diets significantly increased the weight and decreased the pH of the caecal content. The rats fed with InuL-supplemented diet showed approximately 2.9- and 6.8-fold increases in the biomass of Lactobacillus spp. and Bifidobacteria, respectively. Naive and AOM-treated rats fed with inulin-supplemented diet showed ∼1.3- and ∼2.2-fold decreases in the biomass of Escherichia coli and Salmonella enterica serovar Typhi, respectively. Inulins significantly decreased the colonic concentration of phenol, p-cresol and indole. Reduction in the activity of microbial enzymes such as β-glucuronidase, azoreductase and nitroreductase were observed in inulin-treated animals. Reduction in the ACF formation has been observed in inulin-treated groups. Discussion and conclusion The present study demonstrates that dietary

  16. IQ (2-amino-3-methylimidazo[4,5-f]quinoline)- induced aberrant crypt foci and colorectal tumour development in rats fed two different carbohydrate diets

    DEFF Research Database (Denmark)

    Mølck, A.M.; Meyer, Otto A.; Kristiansen, E.;

    2001-01-01

    In most aberrant crypt foci (ACF) and colorectal tumour studies, chemical carcinogens not normally found in food have been used as initiators. In the present study the food-related compound, IQ (2-amino-3-methylimidazo[4,5-f]quinoline), has been used. A diet high in refined carbohydrates has been...... associated with enhanced development of ACF and colorectal cancer in humans. The present study was designed as an integrated part of our earlier published ACF study and follows the animals until tumour development. The aim of the study was to investigate (1) the effect of a refined carbohydrate-rich diet......, liver, skin and Zymbal gland. The data demonstrate that a sucrose-rich diet enhance ACF development. A correlation between the outcome of early and late ACF was seen. However, as the tumour incidence of this study was very low it was not possible to obtain a meaningful correlation between ACF...

  17. Long-term aerobic swimming training by rats reduces the number of aberrant crypt foci in 1,2-dimethylhydrazine-induced colon cancer

    Directory of Open Access Journals (Sweden)

    W. Lunz

    2008-11-01

    Full Text Available We determined the effect of long-term aerobic swimming training regimens of different intensities on colonic carcinogenesis in rats. Male Wistar rats (11 weeks old were given 4 subcutaneous injections (40 mg/kg body weight each of 1,2-dimethyl-hydrazine (DMH, dissolved in 0.9% NaCl containing 1.5% EDTA, pH 6.5, at 3-day intervals and divided into three exercise groups that swam with 0% body weight (EG1, N = 11, 2% body weight (EG2, N = 11, and 4% body weight of load (EG3, N = 10, 20 min/day, 5 days/week for 35 weeks, and one sedentary control group (CG, N = 10. At sacrifice, the colon was removed and counted for tumors and aberrant crypt foci. Tumor size was measured and intra-abdominal fat was weighed. The mean number of aberrant crypt foci was reduced only for EG2 compared to CG (26.21 ± 2.99 vs 36.40 ± 1.53 crypts; P < 0.05. Tumor incidence was not significantly different among groups (CG: 90%; EG1: 72.7%; EG2: 90%; EG3: 80%. Swimming training did not affect either tumor multiplicity (CG: 2.30 ± 0.58; EG1: 2.09 ± 0.44; EG2: 1.27 ± 0.19; EG3: 1.50 ± 0.48 tumors or size (CG: 1.78 ± 0.24; EG1: 1.81 ± 0.14; EG2: 1.55 ± 0.21; EG3: 2.17 ± 0.22 cm³. Intra-abdominal fat was not significantly different among groups (CG: 10.54 ± 2.73; EG1: 6.12 ± 1.15; EG2: 7.85 ± 1.24; EG3: 5.11 ± 0.74 g. Aerobic swimming training with 2% body weight of load protected against the DMH-induced preneoplastic colon lesions, but not against tumor development in the rat.

  18. Different effects of short- and long-chained fructans on large intestinal physiology and carcinogen-induced aberrant crypt foci in rats.

    Science.gov (United States)

    Poulsen, Morten; Mølck, Anne-Marie; Jacobsen, Bodil Lund

    2002-01-01

    Inulin-type fructans, which are nondigestible carbohydrates, have been shown to modulate the number of induced preneoplastic lesions in the colon as well as the colonic microflora in laboratory animals. The present study was designed to investigate the effect of a short- and long-chained inulin-type fructan on 1,2-dimethylhydrazine dihydrochloride-induced aberrant crypt foci (ACF) in the rat colon. In addition, the present study investigated the influence of chain length, dietary level (5% or 15%), and duration of feeding (5 or 10 wk) on the following intestinal parameters supposed to be involved in the development of ACF: microflora, short-chain fatty acids, pH, and cell proliferation. A 3-wk pretreatment period with both fructans was included. Feeding the long-chained fructan (5% or 15%) significantly inhibited the numbers of small and total ACF after 5 and 10 wk. The short-chained fructan (15%) inhibited the number of small and total ACF after 5 and 10 wk but significantly increased the numbers of medium and large ACF after 10 wk. In conclusion, the effect on ACF outcome was influenced by the chain length of the fructans. PMID:12416260

  19. A phase IIa randomized, double-blind trial of erlotinib in inhibiting epidermal growth factor receptor signaling in aberrant crypt foci of the colorectum.

    Science.gov (United States)

    Gillen, Daniel L; Meyskens, Frank L; Morgan, Timothy R; Zell, Jason A; Carroll, Robert; Benya, Richard; Chen, Wen-Pin; Mo, Allen; Tucker, Chris; Bhattacharya, Asmita; Huang, Zhiliang; Arcilla, Myra; Wong, Vanessa; Chung, Jinah; Gonzalez, Rachel; Rodriguez, Luz Maria; Szabo, Eva; Rosenberg, Daniel W; Lipkin, Steven M

    2015-03-01

    Colorectal cancer progresses through multiple distinct stages that are potentially amenable to chemopreventative intervention. Epidermal growth factor receptor (EGFR) inhibitors are efficacious in advanced tumors including colorectal cancer. There is significant evidence that EGFR also plays important roles in colorectal cancer initiation, and that EGFR inhibitors block tumorigenesis. We performed a double-blind randomized clinical trial to test whether the EGFR inhibitor erlotinib given for up to 30 days had an acceptable safety and efficacy profile to reduce EGFR signaling biomarkers in colorectal aberrant crypt foci (ACF), a subset of which progress to colorectal cancer, and normal rectal tissue. A total of 45 patients were randomized to one of three erlotinib doses (25, 50, and 100 mg) with randomization stratified by nonsteroidal anti-inflammatory drug (NSAID) use. There were no unanticipated adverse events with erlotinib therapy. Erlotinib was detected in both normal rectal mucosa and ACFs. Colorectal ACF phosphorylated ERK (pERK), phosphorylated EGFR (pEGFR), and total EGFR signaling changes from baseline were modest and there was no dose response. Overall, this trial did not meet is primary efficacy endpoint. Colorectal EGFR signaling inhibition by erlotinib is therefore likely insufficient to merit further studies without additional prescreening stratification or potentially longer duration of use.

  20. A Method for Serial Tissue Processing and Parallel Analysis of Aberrant Crypt Morphology, Mucin Depletion, and Beta-Catenin Staining in an Experimental Model of Colon Carcinogenesis

    Directory of Open Access Journals (Sweden)

    McGinley John N

    2010-05-01

    Full Text Available Abstract The use of architectural and morphological characteristics of cells for establishing prognostic indicators by which individual pathologies are assigned grade and stage is a well-accepted practice. Advances in automated micro- and macroscopic image acquisition and digital image analysis have created new opportunities in the field of prognostic assessment; but, one area in experimental pathology, animal models for colon cancer, has not taken advantage of these opportunities. This situation is primarily due to the methods available to evaluate the colon of the rodent for the presence of premalignant and malignant pathologies. We report a new method for the excision and processing of the entire colon of the rat and illustrate how this procedure permitted the quantitative assessment of aberrant crypt foci (ACF, a premalignant colon pathology, for characteristics consistent with progression to malignancy. ACF were detected by methylene blue staining and subjected to quantitative morphometric analysis. Colons were then restained with high iron diamine–alcian blue for assessment of mucin depletion using an image overlay to associate morphometric data with mucin depletion. The subsequent evaluation of ACF for beta-catenin staining is also demonstrated. The methods described are particularly relevant to the screening of compounds for cancer chemopreventive activity. Additional file 1 Click here for file

  1. A Method for Serial Tissue Processing and Parallel Analysis of Aberrant Crypt Morphology, Mucin Depletion, and Beta-Catenin Staining in an Experimental Model of Colon Carcinogenesis

    Directory of Open Access Journals (Sweden)

    McGinley John

    2010-01-01

    Full Text Available Abstract The use of architectural and morphological characteristics of cells for establishing prognostic indicators by which individual pathologies are assigned grade and stage is a well-accepted practice. Advances in automated micro- and macroscopic image acquisition and digital image analysis have created new opportunities in the field of prognostic assessment; but, one area in experimental pathology, animal models for colon cancer, has not taken advantage of these opportunities. This situation is primarily due to the methods available to evaluate the colon of the rodent for the presence of premalignant and malignant pathologies. We report a new method for the excision and processing of the entire colon of the rat and illustrate how this procedure permitted the quantitative assessment of aberrant crypt foci (ACF, a premalignant colon pathology, for characteristics consistent with progression to malignancy. ACF were detected by methylene blue staining and subjected to quantitative morphometric analysis. Colons were then restained with high iron diamine–alcian blue for assessment of mucin depletion using an image overlay to associate morphometric data with mucin depletion. The subsequent evaluation of ACF for beta-catenin staining is also demonstrated. The methods described are particularly relevant to the screening of compounds for cancer chemopreventive activity. Additional file 1 Click here for file

  2. Soy Saponins Meditate the Progression of Colon Cancer in Rats by Inhibiting the Activity of β-Glucuronidase and the Number of Aberrant Crypt Foci but Not Cyclooxygenase-2 Activity

    OpenAIRE

    Yu-Wei Guo; Yue-Hwa Chen; Wan-Chun Chiu; Hsiang Liao; Shyh-Hsiang Lin

    2013-01-01

    Objective. The effect of extracted crude soybean saponins on preneoplastic lesions, aberrant crypt foci (ACF), and the related mechanism were investigated. Research Methods and Procedures. Rats were assigned into five groups according to different doses of extracted crude soybean saponins and received 1,2-dimethylhydrazine (DMH) injection in week 5. In week 15, all rats were sacrificed. The number of ACFs, the cyclooxygenase-2 (COX-2) protein expression, the level of prostaglandins E2 (PGE2),...

  3. Modelling the formation of polycentric chromosome aberrations

    Energy Technology Data Exchange (ETDEWEB)

    Sachs, R.K.; Tarver, J. (California Univ., Berkeley, CA (United States). Dept. of Mathematics); Yates, B.L.; Morgan, W.F. (California Univ., San Francisco, CA (United States))

    1992-10-01

    Exchange-type chromosome aberrations produced by ionizing radiation or restriction enzymes are believed to result from pairwise interaction of DNA double-strand breaks (dsb). In addition to dicentrics, such aberrations may include higher-order polycentries (tricentries, tetracentrics, etc.). The authors have developed computer programs that calculate the probability of the various polycentrics for a given average number of pairwise interactions. Two models are used. Model I incorporates kinetic competition between restitution, complete exchanges (illegitimate recombination events), and incomplete exchanges. Model II allows unrestituted breaks even if there is no recombination. The models were applied to experimental observations of aberrations produced in G[sub 1] Chinese hamster ovary cells after electroporation with the restriction enzyme PvuII, which produces blunt-end dsb. (author).

  4. Modelling the formation of polycentric chromosome aberrations

    International Nuclear Information System (INIS)

    Exchange-type chromosome aberrations produced by ionizing radiation or restriction enzymes are believed to result from pairwise interaction of DNA double-strand breaks (dsb). In addition to dicentrics, such aberrations may include higher-order polycentries (tricentries, tetracentrics, etc.). The authors have developed computer programs that calculate the probability of the various polycentrics for a given average number of pairwise interactions. Two models are used. Model I incorporates kinetic competition between restitution, complete exchanges (illegitimate recombination events), and incomplete exchanges. Model II allows unrestituted breaks even if there is no recombination. The models were applied to experimental observations of aberrations produced in G1 Chinese hamster ovary cells after electroporation with the restriction enzyme PvuII, which produces blunt-end dsb. (author)

  5. Dietary aloe vera gel powder and extract inhibit azoxymethane- induced colorectal aberrant crypt foci in mice fed a high- fat diet.

    Science.gov (United States)

    Chihara, Takeshi; Shimpo, Kan; Kaneko, Takaaki; Beppu, Hidehiko; Higashiguchi, Takashi; Sonoda, Shigeru; Tanaka, Miyuki; Yamada, Muneo; Abe, Fumiaki

    2015-01-01

    Aloe vera gel exhibits protective effects against insulin resistance as well as lipid-lowering and anti-diabetic effects. The anti-diabetic compounds in this gel were identified as Aloe-sterols. Aloe vera gel extract (AVGE) containing Aloe-sterols has recently been produced using a new procedure. We previously reported that AVGE reduced large-sized intestinal polyps in Apc-deficient Min mice fed a high fat diet (HFD), suggesting that Aloe vera gel may protect against colorectal cancer. In the present study, we examined the effects of Aloe vera gel powder (AVGP) and AVGE on azoxymethane-induced colorectal preneoplastic aberrant crypt foci (ACF) in mice fed a HFD. Male C57BL/6J mice were given a normal diet (ND), HFD, HFD containing 0.5% carboxymethyl cellulose solution, which was used as a solvent for AVGE (HFDC), HFD containing 3% or 1% AVGP, and HFDC containing 0.0125% (H-) or 0.00375% (L-) AVGE. The number of ACF was significantly lower in mice given 3% AVGP and H-AVGE than in those given HFD or HFDC alone. Moreover, 3% AVGP, H-AVGE and L-AVGE significantly decreased the mean Ki-67 labeling index, assessed as a measure of cell proliferation in the colonic mucosa. In addition, hepatic phase II enzyme glutathione S-transferase mRNA levels were higher in the H-AVGE group than in the HFDC group. These results suggest that both AVGP and AVGE may have chemopreventive effects on colorectal carcinogenesis under the HFD condition. Furthermore, the concentration of Aloe-sterols was similar between 3% AVGP and H-AVGE, suggesting that Aloe-sterols were the main active ingredients in this experiment.

  6. The modulatory influence of p-methoxycinnamic acid, an active rice bran phenolic acid, against 1,2-dimethylhydrazine-induced lipid peroxidation, antioxidant status and aberrant crypt foci in rat colon carcinogenesis.

    Science.gov (United States)

    Sivagami, Gunasekaran; Karthikkumar, Venkatachalam; Balasubramanian, Thangavel; Nalini, Namashivayam

    2012-03-01

    We investigated the chemopreventive effect of p-methoxycinnamic acid (p-MCA), an active phenolic acid of rice bran, turmeric, and Kaemperfia galanga against 1,2-dimethylhydrazine-induced rat colon carcinogenesis. Male albino Wistar rats were randomly divided into six groups. Group 1 consisted of control rats that received a modified pellet diet and 0.1% carboxymethyl cellulose. The rats in Group 2 received a modified pellet diet supplemented with p-MCA [80 mg/kg body weight (b.wt.) post-orally (p.o.)] everyday. The rats in Groups 3-6 received 1,2-dimethylhydrazine (DMH) (20 mg/kg b.wt.) via subcutaneous injections once a week for the first 4 weeks; additionally, the rats in Groups 4, 5 and 6 received p-MCA at doses of 20, 40 and 80 mg/kg b.wt./day p.o., respectively, everyday for 16 weeks. The rats were sacrificed at the end of the experimental period of 16 weeks. The DMH-treated rats exhibited an increased incidence of aberrant crypt foci (ACF) development; an increased crypt multiplicity; decreased concentrations of tissue lipid peroxidation markers such as thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD) and lipid hydroperoxides (LOOH); decreased levels of tissue enzymic antioxidants such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR); and decreased levels of non-enzymic antioxidants such as reduced glutathione (GSH) and vitamins C, E and A in the colon. Supplementation with p-MCA significantly reversed these changes and significantly inhibited the formation of ACF and its multiplicity. Thus, our findings demonstrate that p-MCA exerts a strong chemopreventive activity against 1,2-dimethylhydrazine-induced colon carcinogenesis by virtue of its ability to prevent the alterations in DMH-induced circulatory and tissue oxidative stress and preneoplastic changes. p-MCA was more effective when administered at a dose of 40 mg/kg b.wt. than at the other two doses tested. PMID:22326950

  7. Short curcumin treatment modulates oxidative stress, arginase activity, aberrant crypt foci, and TGF-β1 and HES-1 transcripts in 1,2-dimethylhydrazine-colon carcinogenesis in mice

    International Nuclear Information System (INIS)

    Highlights: ► 1,2-Dimethylhydrazine (DMH) toxicity was driven by oxidative stress. ► Arginase activity correlated to aberrant crypt foci (ACF). ► Curcumin diet restored redox status and induced apoptosis of dysplastic ACF. ► Curcumin reduced arginase activity and up regulated TGF-β1 and HES-1 transcripts. -- Abstract: This study investigated the effect of short curcumin treatment, a natural antioxidant on 1,2-dimethylhydrazine (DMH)-induced aberrant crypt foci (ACF) in mice. The incidence of aberrant crypt foci (ACF) was 100%, with 54 ± 6 per colon, 10 weeks after the first DMH injection and reached 67 ± 12 per colon after 12 weeks. A high level of undifferentiated goblet cells and a weak apoptotic activity were shown in dysplastic ACF. The morphological alterations of colonic mucosa were associated to severe oxidative stress ratio with 43% increase in malondialdehyde vs. 36% decrease in GSH. DMH also increased inducible nitric synthase (iNOS) mRNA transcripts (250%), nitrites level (240%) and arginase activity (296%), leading to nitrosative stress and cell proliferation. Curcumin treatment, starting at week 10 post-DMH injection for 14 days, reduced the number of ACF (40%), iNOS expression (25%) and arginase activity (73%), and improved redox status by approximately 46%, compared to DMH-treated mice. Moreover, curcumin induced apoptosis of dysplastic ACF cells without restoring goblet cells differentiation. Interestingly, curcumin induced a parallel increase in TGF-β1 and HES-1 transcripts (42% and 26%, respectively). In conclusion, the protective effect of curcumin was driven by the reduction of arginase activity and nitrosative stress. The up regulation of TGF-β1 and HES-1 expression by curcumin suggests for the first time, a potential interplay between these signalling pathways in the chemoprotective mechanism of curcumin.

  8. Effect of etoricoxib, a cyclooxygenase-2 selective inhibitor on aberrant crypt formation and apoptosis in 1,2 dimethyl hydrazine induced colon carcinogenesis in rat model Efecto del etoricoxib, un inhibidor selectivo de la ciclooxigenasa-2, sobre la formación de criptas aberrantes y la apoptosis en un modelo murino de carcinogénesis de colon inducidad por 1,2-dimetilhidracina

    Directory of Open Access Journals (Sweden)

    P. Sharma

    2010-02-01

    Full Text Available Etoricoxib, a second generation selective cyclooxygenase-2 (COX-2 inhibitor had been studied for the chemopreventive response at its therapeutic anti-inflammatory dose in 1,2-dimethylhydrazine (DMH induced colon carcinogenesis in rat model. Eight to ten weeks old male rats of Sprague-Dawley strain were divided into four groups. While group 1 served as control and received the vehicle of the drugs, group 2 and 3 were administered freshly prepared DMH in 1mM EDTA-saline (pH 7.0 (30 mg/kg body wt/week, subcutaneously. Group 3 was also given a daily treatment of etoricoxib (0.6 mg/kg body wt orally while the group 4 received the same amount of etoricoxib only, prepared in 0.5% carboxymethyl cellulose. Animals were sacrificed at the end of 6 weeks, body weight recorded and the colons were subjected to macroscopic and histopathological studies. The maximum number of raised mucosal lesions called the multiple plaque lesions (MPL were found in the DMH group which significantly reverted back in the DMH + etoricoxib group, while very few MPLs were recorded in the control and etoricoxib only group. Similarly, the number of aberrant crypt foci (ACF, the point of future carcinogenic growth, was recorded more in the DMH group and significantly less in the DMH + etoricoxib group. The histopathological analysis showed the presence of severe hyperplasia, occasional dysplasia and aggregates of lymphoid cells in the localized regions. Etoricoxib group showed near normal histological features with the crypt architecture and the surrounding stromal tissue remaining intact. To ascertain the molecular mechanism of such anti-carcinogenic features the colonocytes were isolated and studied in primary culture for the evidence of apoptosis by fluorescent staining and genotoxic changes by single cell gel electrophoresis assay (comet assay which shows that the DMH treated animals produced much less apoptotic nuclei but more comet producing cell, while these features were

  9. De Novo Formation of Insulin-Producing “Neo-β Cell Islets” from Intestinal Crypts

    Directory of Open Access Journals (Sweden)

    Yi-Ju Chen

    2014-03-01

    Full Text Available The ability to interconvert terminally differentiated cells could serve as a powerful tool for cell-based treatment of degenerative diseases, including diabetes mellitus. To determine which, if any, adult tissues are competent to activate an islet β cell program, we performed an in vivo screen by expressing three β cell “reprogramming factors” in a wide spectrum of tissues. We report that transient intestinal expression of these factors—Pdx1, MafA, and Ngn3 (PMN—promotes rapid conversion of intestinal crypt cells into endocrine cells, which coalesce into “neoislets” below the crypt base. Neoislet cells express insulin and show ultrastructural features of β cells. Importantly, intestinal neoislets are glucose-responsive and able to ameliorate hyperglycemia in diabetic mice. Moreover, PMN expression in human intestinal “organoids” stimulates the conversion of intestinal epithelial cells into β-like cells. Our results thus demonstrate that the intestine is an accessible and abundant source of functional insulin-producing cells.

  10. Influence of a Dietary Fiber on Development of Dimethylhydrazine-Induced Aberrant Crypt Foci and Colon Tumor Incidence in Wistar Rats

    DEFF Research Database (Denmark)

    Thorup, I.; Meyer, Otto A.; Kristiansen, E.

    1994-01-01

    between duration of intake of high-fiber diet and number of animals with ACF, as well as the total number of ACF and number of small A CF (1-3 crypts) per affected animal. The previously reported data showed no protective effect of the dietary fiber at any stage of the colorectal carcinogenic process...

  11. The chemopotential effect of Annona muricata leaves against azoxymethane-induced colonic aberrant crypt foci in rats and the apoptotic effect of Acetogenin Annomuricin E in HT-29 cells: a bioassay-guided approach.

    Directory of Open Access Journals (Sweden)

    Soheil Zorofchian Moghadamtousi

    Full Text Available Annona muricata has been used in folk medicine for the treatment of cancer and tumors. This study evaluated the chemopreventive properties of an ethyl acetate extract of A. muricata leaves (EEAML on azoxymethane-induced colonic aberrant crypt foci (ACF in rats. Moreover, the cytotoxic compound of EEAML (Annomuricin E was isolated, and its apoptosis-inducing effect was investigated against HT-29 colon cancer cell line using a bioassay-guided approach. This experiment was performed on five groups of rats: negative control, cancer control, EEAML (250 mg/kg, EEAML (500 mg/kg and positive control (5-fluorouracil. Methylene blue staining of colorectal specimens showed that application of EEAML at both doses significantly reduced the colonic ACF formation compared with the cancer control group. Immunohistochemistry analysis showed the down-regulation of PCNA and Bcl-2 proteins and the up-regulation of Bax protein after administration of EEAML compared with the cancer control group. In addition, an increase in the levels of enzymatic antioxidants and a decrease in the malondialdehyde level of the colon tissue homogenates were observed, suggesting the suppression of lipid peroxidation. Annomuricin E inhibited the growth of HT-29 cells with an IC50 value of 1.62 ± 0.24 μg/ml after 48 h. The cytotoxic effect of annomuricin E was further substantiated by G1 cell cycle arrest and early apoptosis induction in HT-29 cells. Annomuricin E triggered mitochondria-initiated events, including the dissipation of the mitochondrial membrane potential and the leakage of cytochrome c from the mitochondria. Prior to these events, annomuricin E activated caspase 3/7 and caspase 9. Upstream, annomuricin E induced a time-dependent upregulation of Bax and downregulation of Bcl-2 at the mRNA and protein levels. In conclusion, these findings substantiate the usage of A. muricata leaves in ethnomedicine against cancer and highlight annomuricin E as one of the contributing

  12. The chemopotential effect of Annona muricata leaves against azoxymethane-induced colonic aberrant crypt foci in rats and the apoptotic effect of Acetogenin Annomuricin E in HT-29 cells: a bioassay-guided approach.

    Science.gov (United States)

    Zorofchian Moghadamtousi, Soheil; Rouhollahi, Elham; Karimian, Hamed; Fadaeinasab, Mehran; Firoozinia, Mohammad; Ameen Abdulla, Mahmood; Abdul Kadir, Habsah

    2015-01-01

    Annona muricata has been used in folk medicine for the treatment of cancer and tumors. This study evaluated the chemopreventive properties of an ethyl acetate extract of A. muricata leaves (EEAML) on azoxymethane-induced colonic aberrant crypt foci (ACF) in rats. Moreover, the cytotoxic compound of EEAML (Annomuricin E) was isolated, and its apoptosis-inducing effect was investigated against HT-29 colon cancer cell line using a bioassay-guided approach. This experiment was performed on five groups of rats: negative control, cancer control, EEAML (250 mg/kg), EEAML (500 mg/kg) and positive control (5-fluorouracil). Methylene blue staining of colorectal specimens showed that application of EEAML at both doses significantly reduced the colonic ACF formation compared with the cancer control group. Immunohistochemistry analysis showed the down-regulation of PCNA and Bcl-2 proteins and the up-regulation of Bax protein after administration of EEAML compared with the cancer control group. In addition, an increase in the levels of enzymatic antioxidants and a decrease in the malondialdehyde level of the colon tissue homogenates were observed, suggesting the suppression of lipid peroxidation. Annomuricin E inhibited the growth of HT-29 cells with an IC50 value of 1.62 ± 0.24 μg/ml after 48 h. The cytotoxic effect of annomuricin E was further substantiated by G1 cell cycle arrest and early apoptosis induction in HT-29 cells. Annomuricin E triggered mitochondria-initiated events, including the dissipation of the mitochondrial membrane potential and the leakage of cytochrome c from the mitochondria. Prior to these events, annomuricin E activated caspase 3/7 and caspase 9. Upstream, annomuricin E induced a time-dependent upregulation of Bax and downregulation of Bcl-2 at the mRNA and protein levels. In conclusion, these findings substantiate the usage of A. muricata leaves in ethnomedicine against cancer and highlight annomuricin E as one of the contributing compounds in the

  13. Mutations of APC and K-ras gene in aberrant crypt foci from human colon%结直肠粘膜隐窝异常病灶K-ras、APC基因突变的研究

    Institute of Scientific and Technical Information of China (English)

    袁平; 张锦生; 孙孟红; 朱雄增; 施达仁

    2001-01-01

    目的 分析隐窝异常病灶(aberrant crypt foci,ACF)的基因水平变化特点及其作为结直肠癌最早期形态变化的分子依据,探讨ACF与腺瘤之间的关系。方法 经微解剖分离提取15例正常粘膜腺体、34例ACF、15例腺瘤和35例结直肠癌组织进行DNA测序,检测K-ras第12、13、61密码子和APC第15外显子“突变密集区”的突变。结果 正常粘膜无K-ras和APC基因突变,ACF、腺瘤和癌组织K-ras突变率分别为17.6%(6/34)、13.3%(2/15)和14.3%(5/35),3者突变率相近。4例ACF、腺瘤和癌组织的突变位于12密码子的第2碱基(GGT→GAT),2例ACF突变发生在13密码子的第2碱基(GGC→GAC)。ACF中K-ras的突变特点与同来源的癌组织保持一致,即患者年龄较大,大体以隆起型为主,所有组织未发现有61密码子的突变。癌和腺瘤APC基因突变率相近,癌为22.9%(8/35),腺瘤为26.7%(4/15)明显高于ACF的2.9%(1/34,P<0.05),癌组织APC与患者的年龄、肿瘤位置、大体类型、组织分化程度无关。结论 ACF可能是结直肠癌最早期的形态改变,ACF的形态学变化、部分基因的改变均有别于腺瘤,提示:(1)ACF有可能是腺瘤前的形态改变;(2) 结直肠癌的发生可能存在“正常上皮→ACF→癌变”这一途径。%Objective To analyze the mutations of K-ras and APC gene in normal colorectal mucosa, aberrant crypt foci (ACF), adenoma and colorectal carcinoma(CRC); To study the genetic alteration in ACF and its possibility of being a molecular marker of very early colon cancer and to explore the relationship of ACF and colorectal adenoma. Methods DNA from 35 CRC, 15 adenomas, 34 ACF and 15 cases of normal mucosa with mucous glands were isolated by micro-dissection. Direct gene sequencing of k-ras gene including codon 12, 13 and 61 as well as the mutation cluster region (MCR) of APC gene. Results Mutation frequency of

  14. Analysis of endoscopic and pathological characteristics of 256 cases of colon aberrant crypt foci%256例大肠异常隐窝灶的内镜与病理特征分析

    Institute of Scientific and Technical Information of China (English)

    韩明; 郭文; 文剑波; 文萍; 龚敏; 李兴; 赖丽霞; 付云辉; 刘立玺

    2013-01-01

    目的 了解大肠异常隐窝灶的内镜和病理特点,探讨ACF与结直肠肿瘤的关系.方法 随机选择2011年8月-2012年3月就诊于江西省萍乡市人民医院准备接受结肠镜检查的患者370例,在距肛门25~30cm以下给予0.4%靛胭脂染色后观察、记录发现远端大肠ACF病例数及ACF数目,并且行病理检查.结果 370例患者共发现256例ACF病例(69.19%).正常黏膜组、增生性息肉组、腺瘤组、结肠癌组ACF患病率分别为58.21%、78.18%、82.05%、88.89%.256例ACF患者Ⅰ级106例(41.41%)、Ⅱ级82例(32.03%)、Ⅲ级68例(26.56%).病理有异型增生病例数39例(10.54%),均为轻度异型增生;病理无异型增生217例(58.65%).有ACF组增生性息肉的发生率为16.8%,腺瘤的发生率25.0%,结直肠癌的发生率12.5%;而无ACF组分别为10.53%、12.58%、3.51%.结论 异常隐窝灶是常见结肠镜下病变,异型增生ACF病变并不少见.ACF可能是结肠腺瘤和大肠癌的独立预测因素.%Objective To analyze endoscopic and pathological characteristics of colon aberrant crypt foci (ACF) and to investigate their relationship with carcinoma.Methods 370 outpatients undergoing routine colonoscopy were selected from Jiangxi Pingxiang People' s Hospital from Aug.2011 to Mar.2012.0.4% indigocarmine was applied to stain colon mucosa 25 ~30 cm away from anus to search colon ACF,biopsy was performed to count ACF number.Resuits ACF were found in 256 cases (69.19%).In groups of normal colon mucosa,hyperplastic polyp,adenoid tumor,carcinoma,the morbidity rates of ACF were 58.21%,78.18%,82.05%,88.89% respectively.In 256 cases of ACF,there were 106 cases (41.41%) in grade Ⅰ,82 cases (32.03%) in grade Ⅱ,68 cases (26.56%) in grade Ⅲ.For pathological characteristics,39 cases (10.54%) with dysplasia were in light degree,217 cases (58.65%) with no dysplasia.In 256 cases of ACF,16.8% was hyperplastic polyp,25.0% was

  15. Simulation of the Formation of DNA Double Strand Breaks and Chromosome Aberrations in Irradiated Cells

    Science.gov (United States)

    Plante, Ianik; Ponomarev, Artem L.; Wu, Honglu; Blattnig, Steve; George, Kerry

    2014-01-01

    The formation of DNA double-strand breaks (DSBs) and chromosome aberrations is an important consequence of ionizing radiation. To simulate DNA double-strand breaks and the formation of chromosome aberrations, we have recently merged the codes RITRACKS (Relativistic Ion Tracks) and NASARTI (NASA Radiation Track Image). The program RITRACKS is a stochastic code developed to simulate detailed event-by-event radiation track structure: [1] This code is used to calculate the dose in voxels of 20 nm, in a volume containing simulated chromosomes, [2] The number of tracks in the volume is calculated for each simulation by sampling a Poisson distribution, with the distribution parameter obtained from the irradiation dose, ion type and energy. The program NASARTI generates the chromosomes present in a cell nucleus by random walks of 20 nm, corresponding to the size of the dose voxels, [3] The generated chromosomes are located within domains which may intertwine, and [4] Each segment of the random walks corresponds to approx. 2,000 DNA base pairs. NASARTI uses pre-calculated dose at each voxel to calculate the probability of DNA damage at each random walk segment. Using the location of double-strand breaks, possible rejoining between damaged segments is evaluated. This yields various types of chromosomes aberrations, including deletions, inversions, exchanges, etc. By performing the calculations using various types of radiations, it will be possible to obtain relative biological effectiveness (RBE) values for several types of chromosome aberrations.

  16. Using crypts as iris minutiae

    Science.gov (United States)

    Shen, Feng; Flynn, Patrick J.

    2013-05-01

    Iris recognition is one of the most reliable biometric technologies for identity recognition and verification, but it has not been used in a forensic context because the representation and matching of iris features are not straightforward for traditional iris recognition techniques. In this paper we concentrate on the iris crypt as a visible feature used to represent the characteristics of irises in a similar way to fingerprint minutiae. The matching of crypts is based on their appearances and locations. The number of matching crypt pairs found between two irises can be used for identity verification and the convenience of manual inspection makes iris crypts a potential candidate for forensic applications.

  17. The phenomenology and neurobiology of delusion formation during psychosis onset: Jaspers, Truman symptoms, and aberrant salience.

    Science.gov (United States)

    Mishara, Aaron L; Fusar-Poli, Paolo

    2013-03-01

    Following the publication of Karl Jaspers' General Psychopathology (1913), delusions have been characterized as being nonunderstandable in terms of the person's biography, motivations, and historical-cultural context. According to Jaspers, this loss of understandability is due to an underlying neurobiological process, which has interrupted the normal development of the individual's personality. Inheriting the 19th-century division between the natural- and human-historical sciences, Jaspers emphasizes the psychological understanding of mental disorders as narrative-based, holistic, and contextual. By doing so, he embraces cultural, ethnic, and individual differences and anticipates a person-centered medicine. However, he also affirms the value of explanatory neurobiological approaches, especially in the research and diagnosis of delusions. The phenomenological approach leads to neurobiological hypotheses, which can be tested experimentally. The present article addresses these issues by illustrating Jaspers' fundamental contribution to current neurobiological research concerning the formation of delusions during early phases of psychosis. Specifically, we present delusional mood and Truman symptoms as core phenomenological features at the origin of psychosis onset, and we discuss their neurobiological substrate with the aberrant salience and dopamine dysregulation models. Jaspers and his successors' phenomenological approach suggests that delusion is formed through loss of context in its experiential-perceptual origins. This is consistent with the more recent neurobiological models.

  18. Bodies Folded in Migrant Crypts

    DEFF Research Database (Denmark)

    Galis, Vasilis; Tzokas, Spyros; Tympas, Aristotle

    2016-01-01

    and human migrants generates a dis/abled subject. In this context, dis/ability may be a cause or consequence of migration, both in physical/material (the folding of bodies in the crypt) and cultural/semiotic terms, and may become a barrier to accessing protection, to entering and/or crossing a country...

  19. Optimality in the Development of Intestinal Crypts

    Science.gov (United States)

    van Oudenaarden, Alexander

    2012-02-01

    Intestinal crypts in mammals are comprised of long-lived stem cells and shorter-lived progenies, maintained under tight proportions during adult life. Here we ask what are the design principles that govern the dynamics of these proportions during crypt morphogenesis. We use optimal control theory to show that a stem cell proliferation strategy known as a `bang-bang' control minimizes the time to obtain a mature crypt. This strategy consists of a surge of symmetric stem cell divisions, establishing the entire stem cell pool first, followed by a sharp transition to strictly asymmetric stem cell divisions, producing non-stem cells with a delay. We validate these predictions using lineage tracing and single molecule fluorescent in-situ hybridization of intestinal crypts in newborn mice and find that small crypts are entirely composed of Lgr5 stem cells, which become a minority as crypts further grow. Our approach can be used to uncover similar design principles in other developmental systems.

  20. Neocarzinostatin-induced Rad51 nuclear focus formation is cell cycle regulated and aberrant in AT cells

    International Nuclear Information System (INIS)

    DNA double-stranded breaks are the most detrimental form of DNA damage and, if not repaired properly, may lead to an accumulation of chromosomal aberrations and eventually tumorigenesis. Proteins of the Rad51/Rad52 epitasis group are crucial for the recombinational repair of DNA double-stranded breaks, whereas the Rad50/NBS1/Mre11 nuclease complex is involved in both the recombinational and the end-joining repair of DNA double-stranded breaks. Herein, we demonstrate that the chemotherapeutic enediyne antibiotic neocarzinostatin induced Rad51, but not NBS1, nuclear focus formation in a cell- cycle-dependent manner. Furthermore, neocarzinostatin-induced Rad51 foci formation revealed a slower kinetic change in AT cells, but not in wild-type or NBS cells. In summary, our results suggest that neocarzinostatin induces Rad51 focus formation through an ATM- and cell-cycle-dependent, but NBS1-independent, pathway

  1. Cell organisation in the colonic crypt: a theoretical comparison of the pedigree and niche concepts.

    Directory of Open Access Journals (Sweden)

    Richard C van der Wath

    Full Text Available The intestinal mucosa is a monolayer of rapidly self-renewing epithelial cells which is not only responsible for absorption of water and nutrients into the bloodstream but also acts as a protective barrier against harmful microbes entering the body. New functional epithelial cells are produced from stem cells, and their proliferating progeny. These stem cells are found within millions of crypts (tubular pits spaced along the intestinal tract. The entire intestinal epithelium is replaced every 2-3 days in mice (3-5 days in humans and hence cell production, differentiation, migration and turnover need to be tightly regulated. Malfunctions in this regulation are strongly linked to inflammatory bowel diseases and to the formation of adenomas and ultimately cancerous tumours. Despite a great deal of biological experimentation and observation, precisely how colonic crypts are regulated to produce mature colonocytes remains unclear. To assist in understanding how cell organisation in crypts is achieved, two very different conceptual models of cell behaviour are developed here, referred to as the 'pedigree' and the 'niche' models. The pedigree model proposes that crypt cells are largely preprogrammed and receive minimal prompting from the environment as they move through a routine of cell differentiation and proliferation to become mature colonocytes. The niche model proposes that crypt cells are primarily influenced by the local microenvironments along the crypt, and that predetermined cell behaviour plays a negligible role in their development. In this paper we present a computational model of colonic crypts in the mouse, which enables a comparison of the quality and controllability of mature coloncyte production by crypts operating under these two contrasting conceptual models of crypt regulation.

  2. Optical coherence tomography imaging of colonic crypts in a mouse model of colorectal cancer

    Science.gov (United States)

    Welge, Weston A.; Barton, Jennifer K.

    2016-03-01

    Aberrant crypt foci (ACF) are abnormal epithelial lesions that precede development of colonic polyps. As the earliest morphological change in the development of colorectal cancer, ACF is a highly studied phenomenon. The most common method of imaging ACF is chromoendoscopy using methylene blue as a contrast agent. Narrow- band imaging is a contrast-agent-free modality for imaging the colonic crypts. Optical coherence tomography (OCT) is an attractive alternative to chromoendoscopy and narrow-band imaging because it can resolve the crypt structure at sufficiently high sampling while simultaneously providing depth-resolved data. We imaged in vivo the distal 15 mm of colon in the azoxymethane (AOM) mouse model of colorectal cancer using a commercial swept-source OCT system and a miniature endoscope designed and built in-house. We present en face images of the colonic crypts and demonstrate that different patterns in healthy and adenoma tissue can be seen. These patterns correspond to those reported in the literature. We have previously demonstrated early detection of colon adenoma using OCT by detecting minute thickening of the mucosa. By combining mucosal thickness measurement with imaging of the crypt structure, OCT can be used to correlate ACF and adenoma development in space and time. These results suggest that OCT may be a superior imaging modality for studying the connection between ACF and colorectal cancer.

  3. Hallucinatory experience as aberrant event memory formation: Implications for the pathophysiology of schizophrenia.

    Science.gov (United States)

    Behrendt, Ralf-Peter

    2016-11-01

    If hallucinations are not fundamentally different from normal wakeful experiences, then the neural basis of hallucinations has to be essentially that of consciousness in general. The additional insight that consciousness reflects the formation (as opposed to consolidation) of event (episodic) memories links the pathophysiology of hallucinations to the hippocampus. Perceptions and misperceptions, insofar as they are consciously experienced, constitute contextualized and unitary phenomena (which are embedded as discrete events in the stream of consciousness); they are experiential manifestations of activity patters that recurrently emerge in the CA3 network of the hippocampus (and that are secondarily consolidated into retrievable and declarable memories). The hippocampus, forming allocentric representations of objects in their world context (event memories), is a point of convergence of neocortical sensory processing streams. Moreover, being extensively modulated by the organism's physiological state, the hippocampus embeds such representations in an emotional context and, through its output to the medial prefrontal cortex, guides decision-making and goal-selection processes. Although sensory and associative processing in the neocortex makes an important contribution to the formation of behaviourally adaptive representations in the hippocampus, it is becoming clearer that pattern formation in the hippocampus is in itself the neural correlate of consciousness and that disruptions in relational memory processing in the hippocampus can give rise to hallucinations. Neurobiological and neuroimaging findings in schizophrenia research can be integrated within the proposed conceptual framework. PMID:27492675

  4. Formation of radiation induced chromosome aberrations: involvement of telomeric sequences and telomerase

    International Nuclear Information System (INIS)

    As telomeres are crucial for chromosome integrity; we investigated the role played by telomeric sequences in the formation and in the transmission of radio-induced chromosome rearrangements in human cells. Starting from interstitial telomeric sequences (ITS) as putative region of breakage, we showed that the radiation sensitivity is not equally distributed along chromosomes and. is not affected by ITS. On the contrary, plasmid integration sites are prone to radio-induced breaks, suggesting a possible integration at sites already characterized by fragility. However plasmids do not preferentially insert at radio-induced breaks in human cells immortalized by telomerase. These cells showed remarkable karyotype stability even after irradiation, suggesting a role of telomerase in the genome maintenance despite functional telomeres. Finally, we showed that the presence of more breaks in a cell favors the repair, leading to an increase of transmissible rearrangements. (author)

  5. Formation of radiation induced chromosome aberrations: involvement of telomeric sequences and telomerase

    Energy Technology Data Exchange (ETDEWEB)

    Pirzio, L.

    2004-07-15

    As telomeres are crucial for chromosome integrity; we investigated the role played by telomeric sequences in the formation and in the transmission of radio-induced chromosome rearrangements in human cells. Starting from interstitial telomeric sequences (ITS) as putative region of breakage, we showed that the radiation sensitivity is not equally distributed along chromosomes and. is not affected by ITS. On the contrary, plasmid integration sites are prone to radio-induced breaks, suggesting a possible integration at sites already characterized by fragility. However plasmids do not preferentially insert at radio-induced breaks in human cells immortalized by telomerase. These cells showed remarkable karyotype stability even after irradiation, suggesting a role of telomerase in the genome maintenance despite functional telomeres. Finally, we showed that the presence of more breaks in a cell favors the repair, leading to an increase of transmissible rearrangements. (author)

  6. Fluorescent labelling of intestinal epithelial cells reveals independent long-lived intestinal stem cells in a crypt

    Energy Technology Data Exchange (ETDEWEB)

    Horita, Nobukatsu [Department of Gastroenterology and Hepatology, Graduate School, Tokyo Medical and Dental University (Japan); Tsuchiya, Kiichiro, E-mail: kii.gast@tmd.ac.jp [Department of Advanced Therapeutics for Gastrointestinal Diseases, Graduate School, Tokyo Medical and Dental University (Japan); Hayashi, Ryohei [Department of Gastroenterology and Hepatology, Graduate School, Tokyo Medical and Dental University (Japan); Department of Gastroenterology and Metabolism, Hiroshima University (Japan); Fukushima, Keita; Hibiya, Shuji; Fukuda, Masayoshi; Kano, Yoshihito; Mizutani, Tomohiro; Nemoto, Yasuhiro; Yui, Shiro [Department of Gastroenterology and Hepatology, Graduate School, Tokyo Medical and Dental University (Japan); Okamoto, Ryuichi; Nakamura, Tetsuya [Department of Advanced Therapeutics for Gastrointestinal Diseases, Graduate School, Tokyo Medical and Dental University (Japan); Watanabe, Mamoru [Department of Gastroenterology and Hepatology, Graduate School, Tokyo Medical and Dental University (Japan)

    2014-11-28

    Highlights: • Lentivirus mixed with Matrigel enables direct infection of intestinal organoids. • Our original approach allows the marking of a single stem cell in a crypt. • Time-lapse imaging shows the dynamics of a single stem cell. • Our lentivirus transgene system demonstrates plural long-lived stem cells in a crypt. - Abstract: Background and aims: The dynamics of intestinal stem cells are crucial for regulation of intestinal function and maintenance. Although crypt stem cells have been identified in the intestine by genetic marking methods, identification of plural crypt stem cells has not yet been achieved as they are visualised in the same colour. Methods: Intestinal organoids were transferred into Matrigel® mixed with lentivirus encoding mCherry. The dynamics of mCherry-positive cells was analysed using time-lapse imaging, and the localisation of mCherry-positive cells was analysed using 3D immunofluorescence. Results: We established an original method for the introduction of a transgene into an organoid generated from mouse small intestine that resulted in continuous fluorescence of the mCherry protein in a portion of organoid cells. Three-dimensional analysis using confocal microscopy showed a single mCherry-positive cell in an organoid crypt that had been cultured for >1 year, which suggested the presence of long-lived mCherry-positive and -negative stem cells in the same crypt. Moreover, a single mCherry-positive stem cell in a crypt gave rise to both crypt base columnar cells and transit amplifying cells. Each mCherry-positive and -negative cell contributed to the generation of organoids. Conclusions: The use of our original lentiviral transgene system to mark individual organoid crypt stem cells showed that long-lived plural crypt stem cells might independently serve as intestinal epithelial cells, resulting in the formation of a completely functional villus.

  7. Fluorescent labelling of intestinal epithelial cells reveals independent long-lived intestinal stem cells in a crypt

    International Nuclear Information System (INIS)

    Highlights: • Lentivirus mixed with Matrigel enables direct infection of intestinal organoids. • Our original approach allows the marking of a single stem cell in a crypt. • Time-lapse imaging shows the dynamics of a single stem cell. • Our lentivirus transgene system demonstrates plural long-lived stem cells in a crypt. - Abstract: Background and aims: The dynamics of intestinal stem cells are crucial for regulation of intestinal function and maintenance. Although crypt stem cells have been identified in the intestine by genetic marking methods, identification of plural crypt stem cells has not yet been achieved as they are visualised in the same colour. Methods: Intestinal organoids were transferred into Matrigel® mixed with lentivirus encoding mCherry. The dynamics of mCherry-positive cells was analysed using time-lapse imaging, and the localisation of mCherry-positive cells was analysed using 3D immunofluorescence. Results: We established an original method for the introduction of a transgene into an organoid generated from mouse small intestine that resulted in continuous fluorescence of the mCherry protein in a portion of organoid cells. Three-dimensional analysis using confocal microscopy showed a single mCherry-positive cell in an organoid crypt that had been cultured for >1 year, which suggested the presence of long-lived mCherry-positive and -negative stem cells in the same crypt. Moreover, a single mCherry-positive stem cell in a crypt gave rise to both crypt base columnar cells and transit amplifying cells. Each mCherry-positive and -negative cell contributed to the generation of organoids. Conclusions: The use of our original lentiviral transgene system to mark individual organoid crypt stem cells showed that long-lived plural crypt stem cells might independently serve as intestinal epithelial cells, resulting in the formation of a completely functional villus

  8. Instabilities of monolayered epithelia: shape and structure of villi and crypts

    CERN Document Server

    Hannezo, Edouard; Joanny, Jean-Francois; 10.1103/PhysRevLett.107.078104

    2012-01-01

    We study theoretically the shapes of a dividing epithelial monolayer of cells lying on top of an elastic stroma. The negative tension created by cell division provokes a buckling instability at a finite wave vector leading to the formation of periodic arrays of villi and crypts. The instability is similar to the buckling of a metallic plate under compression. We use the results to rationalize the various structures of the intestinal lining observed \\emph{in vivo}. Taking into account the coupling between cell division and local curvature, we obtain different patterns of villi and crypts, which could explain the different morphologies of the small intestine and the colon.

  9. Breakpoint sites disclose the role of the V(D)J recombination machinery in the formation of T-cell receptor (TCR) and non-TCR associated aberrations in T-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Larmonie, Nicole S D; Dik, Willem A; Meijerink, Jules P P; Homminga, Irene; van Dongen, Jacques J M; Langerak, Anton W

    2013-08-01

    Aberrant recombination between T-cell receptor genes and oncogenes gives rise to chromosomal translocations that are genetic hallmarks in several subsets of human T-cell acute lymphoblastic leukemias. The V(D)J recombination machinery has been shown to play a role in the formation of these T-cell receptor translocations. Other, non-T-cell receptor chromosomal aberrations, such as SIL-TAL1 deletions, have likewise been recognized as V(D)J recombination associated aberrations. Despite the postulated role of V(D)J recombination, the extent of the V(D)J recombination machinery involvement in the formation of T-cell receptor and non-T-cell receptor aberrations in T-cell acute lymphoblastic leukemia is still poorly understood. We performed a comprehensive in silico and ex vivo evaluation of 117 breakpoint sites from 22 different T-cell receptor translocation partners as well as 118 breakpoint sites from non-T-cell receptor chromosomal aberrations. Based on this extensive set of breakpoint data, we provide a comprehensive overview of T-cell receptor and oncogene involvement in T-ALL. Moreover, we assessed the role of the V(D)J recombination machinery in the formation of chromosomal aberrations, and propose an up-dated mechanistic classification on how the V(D)J recombination machinery contributes to the formation of T-cell receptor and non-T-cell receptor aberrations in human T-cell acute lymphoblastic leukemia.

  10. Investigation of computer-aided colonic crypt pattern analysis

    Science.gov (United States)

    Qi, Xin; Pan, Yinsheng; Sivak, Michael V., Jr.; Olowe, Kayode; Rollins, Andrew M.

    2007-02-01

    Colorectal cancer is the second leading cause of cancer-related death in the United States. Approximately 50% of these deaths could be prevented by earlier detection through screening. Magnification chromoendoscopy is a technique which utilizes tissue stains applied to the gastrointestinal mucosa and high-magnification endoscopy to better visualize and characterize lesions. Prior studies have shown that shapes of colonic crypts change with disease and show characteristic patterns. Current methods for assessing colonic crypt patterns are somewhat subjective and not standardized. Computerized algorithms could be used to standardize colonic crypt pattern assessment. We have imaged resected colonic mucosa in vitro (N = 70) using methylene blue dye and a surgical microscope to approximately simulate in vivo imaging with magnification chromoendoscopy. We have developed a method of computerized processing to analyze the crypt patterns in the images. The quantitative image analysis consists of three steps. First, the crypts within the region of interest of colonic tissue are semi-automatically segmented using watershed morphological processing. Second, crypt size and shape parameters are extracted from the segmented crypts. Third, each sample is assigned to a category according to the Kudo criteria. The computerized classification is validated by comparison with human classification using the Kudo classification criteria. The computerized colonic crypt pattern analysis algorithm will enable a study of in vivo magnification chromoendoscopy of colonic crypt pattern correlated with risk of colorectal cancer. This study will assess the feasibility of screening and surveillance of the colon using magnification chromoendoscopy.

  11. File list: Unc.Dig.20.AllAg.Intestinal_crypt [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  12. File list: His.Dig.10.AllAg.Intestinal_crypt [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  13. File list: His.Dig.20.AllAg.Intestinal_crypt [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  14. File list: His.Dig.05.AllAg.Intestinal_crypt [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  15. File list: Unc.Dig.05.AllAg.Intestinal_crypt [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  16. File list: Unc.Dig.50.AllAg.Intestinal_crypt [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  17. File list: His.Dig.50.AllAg.Intestinal_crypt [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  18. Crypt region localization of intestinal stem cells in adults

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The intestinal epithelial lining plays a central role in the digestion and absorption of nutrients, but exists in a harsh luminal environment that necessitates continual renewal. This renewal process involves epithelial cell proliferation in the crypt base and later cell migration from the crypt base to the luminal surface. This process is dependent on multi-potent progenitor cells, or stem cells, located in each crypt. There are about 4 to 6 stem cells per crypt, and these stem cells are believed to generate distinct end-differentiated epithelial cell types, including absorptive cells, goblet cells, enteroendocrine cells and Paneth cells, while also maintaining their own progenitor cell state. Earlier studies suggested that intestinal stem cells were located either in the crypt base interspersed between the Paneth cells [i.e. Crypt base columnar (CBC) cell model] or at an average position of 4 cells from the crypt base [I.e. Label-retaining cells (LRC +4) model]. Recent studies have employed biomarkers in the in vivo mammalian state to more precisely evaluate the location of these progenitor cells in the intestinal crypt. Most notable of these novel markers are Lgr5, a gene that encodes a G-protein-coupled receptor with expression restricted to CBC cells, and Bmi 1, which encodes a chromatin remodeling protein expressed by LRC. These studies raise the possibility that there may be separate stem cell lines or different states of stem cell activation involved in the renewal of normal mammalian intestinal tract.

  19. Expression of a dynamin 2 mutant associated with Charcot-Marie-Tooth disease leads to aberrant actin dynamics and lamellipodia formation.

    Science.gov (United States)

    Yamada, Hiroshi; Kobayashi, Kinue; Zhang, Yubai; Takeda, Tetsuya; Takei, Kohji

    2016-08-15

    Specific mutations in dynamin 2 are linked to Charcot-Marie-Tooth disease (CMT), an inherited peripheral neuropathy. However, the effects of these mutations on dynamin function, particularly in relation to the regulation of the actin cytoskeleton remain unclear. Here, selected CMT-associated dynamin mutants were expressed to examine their role in the pathogenesis of CMT in U2OS cells. Ectopic expression of the dynamin CMT mutants 555Δ3 and K562E caused an approximately 50% decrease in serum stimulation-dependent lamellipodia formation; however, only K562E caused aberrations in the actin cytoskeleton. Immunofluorescence analysis showed that the K562E mutation resulted in the disappearance of radially aligned actin bundles and the simultaneous appearance of F-actin clusters. Live-cell imaging analyses showed F-actin polymers of decreased length assembled into immobile clusters in K562E-expressing cells. The K562E dynamin mutant colocalized with the F-actin clusters, whereas its colocalization with clathrin-coated pit marker proteins was decreased. Essentially the same results were obtained using another cell line, HeLa and NG108-15 cells. The present study is the first to show the association of dynamin CMT mutations with aberrant actin dynamics and lamellipodia, which may contribute to defective endocytosis and myelination in Schwann cells in CMT.

  20. Optical Aberrations and Wavefront

    Directory of Open Access Journals (Sweden)

    Nihat Polat

    2014-08-01

    Full Text Available The deviation of light to create normal retinal image in the optical system is called aberration. Aberrations are divided two subgroup: low-order aberrations (defocus: spherical and cylindrical refractive errors and high-order aberrations (coma, spherical, trefoil, tetrafoil, quadrifoil, pentafoil, secondary astigmatism. Aberrations increase with aging. Spherical aberrations are compensated by positive corneal and negative lenticular spherical aberrations in youth. Total aberrations are elevated by positive corneal and positive lenticular spherical aberrations in elderly. In this study, we aimed to analyze the basic terms regarding optic aberrations which have gained significance recently. (Turk J Ophthalmol 2014; 44: 306-11

  1. Colorectal cancers mimic structural organization of normal colonic crypts.

    Directory of Open Access Journals (Sweden)

    Laura Cernat

    Full Text Available Colonic crypts are stereotypical structures with distinct stem cell, proliferating, and differentiating compartments. Colorectal cancers derive from colonic crypt epithelia but, in contrast, form morphologically disarrayed glands. In this study, we investigated to which extent colorectal cancers phenocopy colonic crypt architecture and thus preserve structural organization of the normal intestinal epithelium. A subset of colon cancers showed crypt-like compartments with high WNT activity and nuclear β-Catenin at the leading tumor edge, adjacent proliferation, and enhanced Cytokeratin 20 expression in most differentiated tumor epithelia of the tumor center. This architecture strongly depended on growth conditions, and was fully reproducible in mouse xenografts of cultured and primary colon cancer cells. Full crypt-like organization was associated with low tumor grade and was an independent prognostic marker of better survival in a collection of 221 colorectal cancers. Our findings suggest that full activation of preserved intestinal morphogenetic programs in colon cancer requires in vivo growth environments. Furthermore, crypt-like architecture was linked with less aggressive tumor biology, and may be useful to improve current colon cancer grading schemes.

  2. Stomatal crypts may facilitate diffusion of CO(2) to adaxial mesophyll cells in thick sclerophylls.

    Science.gov (United States)

    Hassiotou, Foteini; Evans, John R; Ludwig, Martha; Veneklaas, Erik J

    2009-11-01

    In some plants, stomata are exclusively located in epidermal depressions called crypts. It has been argued that crypts function to reduce transpiration; however, the occurrence of crypts in species from both arid and wet environments suggests that crypts may play another role. The genus Banksia was chosen to examine quantitative relationships between crypt morphology and leaf structural and physiological traits to gain insight into the functional significance of crypts. Crypt resistance to water vapour and CO(2) diffusion was calculated by treating crypts as an additional boundary layer partially covering one leaf surface. Gas exchange measurements of polypropylene meshes confirmed the validity of this approach. Stomatal resistance was calculated as leaf resistance minus calculated crypt resistance. Stomata contributed significantly more than crypts to leaf resistance. Crypt depth increased and accounted for an increasing proportion of leaf resistance in species with greater leaf thickness and leaf dry mass per area. All Banksia species examined with leaves thicker than 0.6 mm had their stomata in deep crypts. We propose that crypts function to facilitate CO(2) diffusion from the abaxial surface to adaxial palisade cells in thick leaves. This and other possible functions of stomatal crypts, including a role in water use, are discussed.

  3. APC and K-ras gene mutation in aberrant crypt foci of human colon

    Institute of Scientific and Technical Information of China (English)

    Ping Yuan; Meng Hong Sun; Jin Sheng Zhang; Xiong Zeng Zhu; Da Ren Shi

    2001-01-01

    AIM To study the genetic alteration in ACF andto define the possibility that ACF may be a veryearly morphological lesion with molecularchanges, and to explore the relationshipbetween ACF and colorectal adenoma evencarcinoma.METHODS DNA from 35 CRC, 15 adenomas, 34ACF and 10 normal mucus was isolated by meansof microdissection. Direct gene sequencing of K-ras gene including codon 12, 13 and 61 as well asthe mutation cluster region (MCR) of APC genewas performed.RESULTS K-ras gene mutation frequency inACF, adenoma and carcinoma was 17.6% (6/34), 13.3% (2/ 15), and 14.3% (5/ 35)respectively, showing no difference ( P > 0.05)in K-fas gene mutation among three pathologicprocedures. The K-ras gene mutation inadenoma, carcinoma and 4 ACF restricted incodon 12 (GGT→GAT), but the other 2 mutationsfrom ACF located in codon 13 (GGC→GAC). K-res gene mutation was found more frequently inolder patients and patients with polypoidcancer. No mutation in codon 61 was found in thethree tissue types. Mutation rate of APO gene inadenoma and carcinoma was 22.9% (8/35) and26.7% (4/ 15), which was higher than ACF(2.9%) (P < 0.05). APC gene mutation incarcinoma was not correlated with age ofpatients, location, size and differentiation oftumor.CONCLUSION ACF might be a very earlymorphological lesion in the tumorogenesis ofcolorectal tumor. The morphological feature andgene mutation status was different in ACF andadenoma. ACF is possibly putative"microadenoma" that might be the precursor ofadenoma. In addition, the development of asubgroup of colorectal carcinomas mightundergo a way of "normal epithelium→ ACF→carcinomas".

  4. Chemoprevention of aberrant crypt foci in the colon of rats by dietary onion.

    OpenAIRE

    Taché, Sylviane; Ladam, Aélis; Corpet, Denis E

    2007-01-01

    International audience Onion intake might reduce the risk of colorectal cancer, according to epidemiology. However, Femia showed in 2003 that diets with a 20% onion intake increase carcinogenesis in rats. We speculated this dose was too high. Prevention of initiation was thus tested in 60 rats given a 5% dried onion diet or AIN76 diet, and initiated 12 days later with azoxymethane (AOM, 1x20 mg/kg i.p.), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ, 2x200 mg/kg p.o.), or N-nitroso-N-methylu...

  5. PROMOTION OF TRIHALOMETHANE-INDUCED COLON, ABERRANT CRYPT FOCI (ACF) BY A HIGH FAT DIET

    Science.gov (United States)

    Abstract:Bromodichloromethane (BOCM) and tribromomethane (TBM) enhanced neoplasia in the large intestine of rats when given by corn oil gavage; BOCM in the drinking water to male rats did not induce colon tumors, but did increase liver tumors. However, TBM and a mixture o...

  6. Genotoxic effects of a particular mixture of acetamiprid and alpha-cypermethrin on chromosome aberration, sister chromatid exchange, and micronucleus formation in human peripheral blood lymphocytes.

    Science.gov (United States)

    Kocaman, Ayşe Yavuz; Topaktaş, Mehmet

    2010-04-01

    The genotoxic effects of a particular mixture of acetamiprid (Acm, neonicotinoid insecticide) and alpha-cypermethrin (alpha-cyp, pyrethroid insecticide) on human peripheral lymphocytes were examined in vitro by chromosomal aberrations (CAs), sister chromatid exchange (SCE), and micronucleus (MN) tests. The human peripheral lymphocytes were treated with 12.5 + 2.5, 15 + 5, 17.5 + 7.5, and 20 + 10 microg/mL of Acm+alpha-cyp, respectively, for 24 and 48 h. The mixture of Acm+alpha-cyp induced the CAs and SCEs at all concentrations and treatment times when compared with both the control and solvent control and these increases were concentration-dependent in both treatment times. MN formation was significantly induced at 12.5 + 2.5, 15 + 5, 17.5 + 7.5, microg/mL of Acm+alpha-cyp when compared with both controls although these increases were not concentration-dependent. Binuclear cells could not be detected sufficiently in the highest concentration of the mixture (20 + 10 microg/mL) for both the 24- and 48-h treatment times. Mitotic index (MI), proliferation index (PI) and nuclear division index (NDI) significantly decreased because of the cytotoxic and cytostatic effects of the mixture, at all concentrations for two treatment periods. Significant decreases in MI and PI were concentration dependent at both treatment times. The decrease in NDI was also concentration-dependent at 48-h treatment period. In general, Acm+alpha-cyp inhibited nuclear division more than positive control, mitomycin C (MMC) and showed a higher cytostatic effect than MMC. Furthermore, in this article, the results of combined effects of Acm+alpha-cyp were compared with the results of single effects of Acm or alpha-cyp (Kocaman and Topaktas,2007,2009, respectively). In conclusion, the particular mixture of Acm+alpha-cyp synergistically induced the genotoxicity/cytotoxicity in human peripheral blood lymphocytes.

  7. Crypt abscess-associated microbiota in inflammatory bowel disease and acute self-limited colitis

    Institute of Scientific and Technical Information of China (English)

    Harry; Sokol; Nadia; Vasquez; Nadia; Hoyeau-Idrissi; Philippe; Seksik; Laurent; Beaugerie; Anne; Lavergne-Slove; Philippe; Pochart; Philippe; Marteau

    2010-01-01

    AIM:To evaluate whether crypt abscesses frominflammatory bowel disease(IBD)patients containbacteria and to establish their nature.METHODS:We studied 17 ulcerative colitis patients,11 Crohn's disease patients,7 patients with acute selflimited colitis(ASLC)and normal colonic biopsies from5 subjects who underwent colonoscopy for colon cancer screening.A fluorescent in situ hybridization techniquewas applied to colonic biopsies to assess the microbiotacomposition of the crypts and crypt abscesses.RESULTS:Crypts...

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  2. File list: ALL.Dig.20.AllAg.Intestinal_crypt [Chip-atlas[Archive

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    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

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  5. File list: Oth.Dig.05.AllAg.Intestinal_crypt [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  6. File list: NoD.Dig.10.AllAg.Intestinal_crypt [Chip-atlas[Archive

    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

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  8. File list: Pol.Dig.20.AllAg.Intestinal_crypt [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  9. File list: DNS.Dig.10.AllAg.Intestinal_crypt [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  10. File list: NoD.Dig.05.AllAg.Intestinal_crypt [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  11. File list: ALL.Dig.10.AllAg.Intestinal_crypt [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  12. File list: ALL.Dig.05.AllAg.Intestinal_crypt [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Dig.05.AllAg.Intestinal_crypt mm9 All antigens Digestive tract Intestinal crypt... SRX871676,SRX871675,SRX871671,SRX871672 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Dig.05.AllAg.Intestinal_crypt.bed ...

  13. Paneth Cell-Rich Regions Separated by a Cluster of Lgr5+ Cells Initiate Crypt Fission in the Intestinal Stem Cell Niche.

    Science.gov (United States)

    Langlands, Alistair J; Almet, Axel A; Appleton, Paul L; Newton, Ian P; Osborne, James M; Näthke, Inke S

    2016-06-01

    The crypts of the intestinal epithelium house the stem cells that ensure the continual renewal of the epithelial cells that line the intestinal tract. Crypt number increases by a process called crypt fission, the division of a single crypt into two daughter crypts. Fission drives normal tissue growth and maintenance. Correspondingly, it becomes less frequent in adulthood. Importantly, fission is reactivated to drive adenoma growth. The mechanisms governing fission are poorly understood. However, only by knowing how normal fission operates can cancer-associated changes be elucidated. We studied normal fission in tissue in three dimensions using high-resolution imaging and used intestinal organoids to identify underlying mechanisms. We discovered that both the number and relative position of Paneth cells and Lgr5+ cells are important for fission. Furthermore, the higher stiffness and increased adhesion of Paneth cells are involved in determining the site of fission. Formation of a cluster of Lgr5+ cells between at least two Paneth-cell-rich domains establishes the site for the upward invagination that initiates fission. PMID:27348469

  14. IgA Nephropathy and Henoch-Schoenlein Purpura Nephritis: Aberrant Glycosylation of IgA1, Formation of IgA1-Containing Immune Complexes, and Activation of Mesangial Cells

    DEFF Research Database (Denmark)

    Novak, J.; Moldoveanu, Z.; Renfrow, M.B.;

    2007-01-01

    IgA1 in the circulation and glomerular deposits of patients with IgA nephropathy (IgAN) is aberrantly glycosylated; the hinge-region O-linked glycans are galactose-deficient. The circulating IgA1 of patients with Henoch-Schoenlein purpura nephritis (HSPN) has a similar defect. This aberrancy...... at specific sites. We sought to define the aberrant glycosylation of a galactose-deficient IgA1 myeloma protein and analyze the formation of the immune complexes and their biological activities. Supplementation of serum or cord-blood serum with this IgA1 protein resulted in formation of new IgA1 complexes...... determined the O-glycosylation sites in the hinge region of the IgA1 myeloma protein and IgA1 proteins from sera of IgAN patients. The IgA1 myeloma protein had galactose-deficient sites at residues 228 and/or 230 and 232. These sites reacted with IgG specific to galactose-deficient IgA1. IgA1 from the Ig...

  15. IGF1 stimulates crypt expansion via differential activation of 2 intestinal stem cell populations.

    Science.gov (United States)

    Van Landeghem, Laurianne; Santoro, M Agostina; Mah, Amanda T; Krebs, Adrienne E; Dehmer, Jeffrey J; McNaughton, Kirk K; Helmrath, Michael A; Magness, Scott T; Lund, P Kay

    2015-07-01

    Insulin-like growth factor 1 (IGF1) has potent trophic effects on normal or injured intestinal epithelium, but specific effects on intestinal stem cells (ISCs) are undefined. We used Sox9-enhanced green fluorescent protein (EGFP) reporter mice that permit analyses of both actively cycling ISCs (Sox9-EGFP(Low)) and reserve/facultative ISCs (Sox9-EGFP(High)) to study IGF1 action on ISCs in normal intestine or during crypt regeneration after high-dose radiation-induced injury. We hypothesized that IGF1 differentially regulates proliferation and gene expression in actively cycling and reserve/facultative ISCs. IGF1 was delivered for 5 days using subcutaneously implanted mini-pumps in uninjured mice or after 14 Gy abdominal radiation. ISC numbers, proliferation, and transcriptome were assessed. IGF1 increased epithelial growth in nonirradiated mice and enhanced crypt regeneration after radiation. In uninjured and regenerating intestines, IGF1 increased total numbers of Sox9-EGFP(Low) ISCs and percentage of these cells in M-phase. IGF1 increased percentages of Sox9-EGFP(High) ISCs in S-phase but did not expand this population. Microarray revealed that IGF1 activated distinct gene expression signatures in the 2 Sox9-EGFP ISC populations. In vitro IGF1 enhanced enteroid formation by Sox9-EGFP(High) facultative ISCs but not Sox9-EGFP(Low) actively cycling ISCs. Our data provide new evidence that IGF1 activates 2 ISC populations via distinct regulatory pathways to promote growth of normal intestinal epithelium and crypt regeneration after irradiation.

  16. Foco de criptas aberrantes e câncer da junção colorretal: análise da presença de lesões precoces microscópicas na periferia do câncer colorretal e correlação com a expressão da β-catenina e Ki-67 Aberrant crypt foci and cancer of the colorectal junction: the correlation between β-catenin/Ki-67 expression and the occurrence of early microscopic secondary lesions surrounding periphery colorectal cancer

    Directory of Open Access Journals (Sweden)

    Daniel Cury Ogata

    2010-04-01

    Full Text Available OBJETIVO: Avaliar a presença de foco de criptas aberrantes (FCA em mucosa macroscopicamente normal, localizada na periferia de um câncer colorretal (CCR e correlacionar a progressão tumoral destes FCA para o CCR, por meio da expressão da β-catenina e o Ki-67. MÉTODOS: Utilizou-se 21 espécimes cirúrgicos contendo adenocarcinoma de junção retossigmóide. Foram coletadas amostras localizadas a 1 e 5 cm proximal e distal ao tumor, quando possível, bem como um fragmento da neoplasia. Os FCA foram selecionados. Subseqüentemente foi realizado estudo imunoistoquímico com os anticorpos β-catenina e o Ki-67. RESULTADOS: A expressão nuclear da β-catenina nos adenocarcinomas, revelou freqüência de 81%. O Ki-67 apresentou a mesma freqüência. Apesar disso o coeficiente Kappa revelou fraca concordância entre estes anticorpos. Foram observados 20 FCA, sendo que 13 destes focos localizavam-se nas proximidades do tumor. Nenhum dos FCA apresentou expressão da β-catenina nuclear, tampouco para o Ki-67. CONCLUSÃO: Nas áreas situadas a 1 cm da neoplasia colorretal, foi observada maior concentração de FCA em relação às áreas situadas a 5 cm do tumor. No entanto, não se observou correlação entre a expressão da β-catenina e ki-67 nos colonócitos das criptas aberrantes das áreas estudadas, com as células neoplásicas do adenocarcinoma.OBJECTIVE: To evaluate the occurrence of aberrant crypt foci (ACF in macroscopic normal mucosa surrounding colorectal cancers (CRC; additionally, analyze tumor progression from ACF to CRC by means of β-catenin and Ki-67 expression. METHODS: Twenty-one surgical specimens showing colorectal junction adenocarcinoma were included. Macroscopic normal mucosa proximal and distal to the primary tumor was sampled at a distance of 1 and 5 cm in both sides. A primary tumor sample was also retrieved. Eventually, ACF's were selected and immunohistochemical analysis of β-catenin and Ki-67 were carried out. RESULTS

  17. Paneth cells: maestros of the small intestinal crypts.

    Science.gov (United States)

    Clevers, Hans C; Bevins, Charles L

    2013-01-01

    Paneth cells are highly specialized epithelial cells of the small intestine, where they coordinate many physiological functions. First identified more than a century ago on the basis of their readily discernible secretory granules by routine histology, these cells are located at the base of the crypts of Lieberkühn, tiny invaginations that line the mucosal surface all along the small intestine. Investigations over the past several decades determined that these cells synthesize and secrete substantial quantities of antimicrobial peptides and proteins. More recent studies have determined that these antimicrobial molecules are key mediators of host-microbe interactions, including homeostatic balance with colonizing microbiota and innate immune protection from enteric pathogens. Perhaps more intriguing, Paneth cells secrete factors that help sustain and modulate the epithelial stem and progenitor cells that cohabitate in the crypts and rejuvenate the small intestinal epithelium. Dysfunction of Paneth cell biology contributes to the pathogenesis of chronic inflammatory bowel disease. PMID:23398152

  18. A Model of Colonic Crypts using SBML Spatial

    Directory of Open Access Journals (Sweden)

    Carlo Maj

    2013-09-01

    Full Text Available The Spatial Processes package enables an explicit definition of a spatial environment on top of the normal dynamic modeling SBML capabilities. The possibility of an explicit representation of spatial dynamics increases the representation power of SBML. In this work we used those new SBML features to define an extensive model of colonic crypts composed of the main cellular types (from stem cells to fully differentiated cells, alongside their spatial dynamics.

  19. Crypt cells are involved in kin recognition in larval zebrafish

    Science.gov (United States)

    Biechl, Daniela; Tietje, Kristin; Gerlach, Gabriele; Wullimann, Mario F.

    2016-01-01

    Zebrafish larvae imprint on visual and olfactory kin cues at day 5 and 6 postfertilization, respectively, resulting in kin recognition later in life. Exposure to non-kin cues prevents imprinting and kin recognition. Imprinting depends on MHC class II related signals and only larvae sharing MHC class II alleles can imprint on each other. Here, we analyzed which type of olfactory sensory neuron (OSN) detects kin odor. The single teleost olfactory epithelium harbors ciliated OSNs carrying OR and TAAR gene family receptors (mammals: main olfactory epithelium) and microvillous OSNs with V1R and V2R gene family receptors (mammals: vomeronasal organ). Additionally, teleosts exhibit crypt cells which possess microvilli and cilia. We used the activity marker pERK (phosphorylated extracellular signal regulated kinase) after stimulating 9 day old zebrafish larvae with either non-kin conspecific or food odor. While food odor activated both ciliated and microvillous OSNs, only the latter were activated by conspecific odor, crypt cells showed no activation to both stimuli. Then, we tested imprinted and non-imprinted larvae (full siblings) for kin odor detection. We provide the first direct evidence that crypt cells, and likely a subpopulation of microvillous OSNs, but not ciliated OSNs, play a role in detecting a kin odor related signal. PMID:27087508

  20. Crypt cells are involved in kin recognition in larval zebrafish.

    Science.gov (United States)

    Biechl, Daniela; Tietje, Kristin; Gerlach, Gabriele; Wullimann, Mario F

    2016-01-01

    Zebrafish larvae imprint on visual and olfactory kin cues at day 5 and 6 postfertilization, respectively, resulting in kin recognition later in life. Exposure to non-kin cues prevents imprinting and kin recognition. Imprinting depends on MHC class II related signals and only larvae sharing MHC class II alleles can imprint on each other. Here, we analyzed which type of olfactory sensory neuron (OSN) detects kin odor. The single teleost olfactory epithelium harbors ciliated OSNs carrying OR and TAAR gene family receptors (mammals: main olfactory epithelium) and microvillous OSNs with V1R and V2R gene family receptors (mammals: vomeronasal organ). Additionally, teleosts exhibit crypt cells which possess microvilli and cilia. We used the activity marker pERK (phosphorylated extracellular signal regulated kinase) after stimulating 9 day old zebrafish larvae with either non-kin conspecific or food odor. While food odor activated both ciliated and microvillous OSNs, only the latter were activated by conspecific odor, crypt cells showed no activation to both stimuli. Then, we tested imprinted and non-imprinted larvae (full siblings) for kin odor detection. We provide the first direct evidence that crypt cells, and likely a subpopulation of microvillous OSNs, but not ciliated OSNs, play a role in detecting a kin odor related signal. PMID:27087508

  1. Actinomyces denticolens colonisation identified in equine tonsillar crypts.

    Science.gov (United States)

    Murakami, S; Otaki, M; Hayashi, Y; Higuchi, K; Kobayashi, T; Torii, Y; Yokoyama, E; Azuma, R

    2016-01-01

    Recently, submandibular abscesses associated with Actinomyces denticolens have been reported in horses. The actinomycotic clumps have been observed in the tonsillar crypts. The aim of this study was to demonstrate colonisation of A denticolens in equine tonsils. Twelve equine tonsils obtained from a slaughterhouse were divided into two parts for histopathological examination and for isolation of A denticolens. When actinomycotic clumps were found in these tonsillar crypts, immunohistochemistry using hyperimmune serum against A denticolens (DMS 20671) was performed on the serial sections. To determine whether Actinomyces-like bacteria isolated using immunoantigenic separation technique were A denticolens, the isolates were analysed for the 16S rRNA gene sequence. Actinomycotic clumps were found in the tonsillar crypts of 11 (91.7 per cent) horses. The clumps were of the saprophytic type accompanied with the feedstuffs, but a few clumps were surrounded by inflammatory cells. A denticolens antigens were immunodetected not only in the clumps of 11 (100 per cent) tonsils, but also in the tonsillar parenchyma. Six isolates obtained from four tonsils showed 99.7-99.9 per cent similarity to A denticolens in the 16S rRNA gene sequence. In horses, the colonisation sites of A denticolens are the tonsils, thus the authors suggest that the tonsils provide the intrinsic infection site for A denticolens. PMID:27651913

  2. Aberration Corrected Emittance Exchange

    CERN Document Server

    Nanni, Emilio A

    2015-01-01

    Full exploitation of emittance exchange (EEX) requires aberration-free performance of a complex imaging system including active radio-frequency (RF) elements which can add temporal distortions. We investigate the performance of an EEX line where the exchange occurs between two dimensions with normalized emittances which differ by orders of magnitude. The transverse emittance is exchanged into the longitudinal dimension using a double dog-leg emittance exchange setup with a 5 cell RF deflector cavity. Aberration correction is performed on the four most dominant aberrations. These include temporal aberrations that are corrected with higher order magnetic optical elements located where longitudinal and transverse emittance are coupled. We demonstrate aberration-free performance of emittances differing by 4 orders of magnitude, i.e. an initial transverse emittance of $\\epsilon_x=1$ pm-rad is exchanged with a longitudinal emittance of $\\epsilon_z=10$ nm-rad.

  3. Apc restoration promotes cellular differentiation and reestablishes crypt homeostasis in colorectal cancer

    Science.gov (United States)

    Simon, Janelle; Tschaharganeh, Darjus F; van Es, Johan H; Clevers, Hans; Lowe, Scott W

    2015-01-01

    The Adenomatous Polyposis Coli (APC) tumor suppressor is mutated in the vast majority of human colorectal cancers (CRC) and leads to deregulated Wnt signaling. To determine whether Apc disruption is required for tumor maintenance, we developed a mouse model of CRC whereby Apc can be conditionally suppressed using a doxycycline-regulated shRNA. Apc suppression produces adenomas in both the small intestine and colon that, in the presence of Kras and p53 mutations, can progress to invasive carcinoma. In established tumors, Apc restoration drives rapid and widespread tumor-cell differentiation and sustained regression without relapse. Tumor regression is accompanied by the re-establishment of normal crypt-villus homeostasis, such that once aberrantly proliferating cells reacquire self-renewal and multi-lineage differentiation capability. Our study reveals that CRC cells can revert to functioning normal cells given appropriate signals, and provide compelling in vivo validation of the Wnt pathway as a therapeutic target for treatment of CRC. PMID:26091037

  4. Colonic Crypt Changes during Adenoma Development in Familial Adenomatous Polyposis : Immunohistochemical Evidence for Expansion of the Crypt Base Cell Population

    OpenAIRE

    Boman, Bruce M; Walters, Rhonda; Fields, Jeremy Z.; Kovatich, Albert J.; Zhang, Tao; Isenberg, Gerald A.; Goldstein, Scott D.; Palazzo, Juan P.

    2004-01-01

    Familial adenomatous polyposis patients, who have a germline APC mutation, develop adenomas in normal-appearing colonic mucosa, and in the process usually acquire a mutation in the other APC allele as well. Nonetheless, the cellular mechanisms that link these initiating genetic changes with the earliest tissue changes (upward shift in the labeling index) in colon tumorigenesis are unclear. Based on the tenet that colorectal cancer originates from crypt stem cells (SCs) and on our kinetic mode...

  5. Ectopic activation of Wnt/β-catenin signaling in lens fiber cells results in cataract formation and aberrant fiber cell differentiation.

    Directory of Open Access Journals (Sweden)

    Barbora Antosova

    Full Text Available The Wnt/β-catenin signaling pathway controls many processes during development, including cell proliferation, cell differentiation and tissue homeostasis, and its aberrant regulation has been linked to various pathologies. In this study we investigated the effect of ectopic activation of Wnt/β-catenin signaling during lens fiber cell differentiation. To activate Wnt/β-catenin signaling in lens fiber cells, the transgenic mouse referred to as αA-CLEF was generated, in which the transactivation domain of β-catenin was fused to the DNA-binding protein LEF1, and expression of the transgene was controlled by αA-crystallin promoter. Constitutive activation of Wnt/β-catenin signaling in lens fiber cells of αA-CLEF mice resulted in abnormal and delayed fiber cell differentiation. Moreover, adult αA-CLEF mice developed cataract, microphthalmia and manifested downregulated levels of γ-crystallins in lenses. We provide evidence of aberrant expression of cell cycle regulators in embryonic lenses of αA-CLEF transgenic mice resulting in the delay in cell cycle exit and in the shift of fiber cell differentiation to the central fiber cell compartment. Our results indicate that precise regulation of the Wnt/β-catenin signaling activity during later stages of lens development is essential for proper lens fiber cell differentiation and lens transparency.

  6. Fluctuations of cell population in a colonic crypt

    Science.gov (United States)

    Pei, Qi-ming; Zhan, Xuan; Yang, Li-jian; Bao, Chun; Cao, Wei; Li, An-bang; Rozi, Anvar; Jia, Ya

    2014-03-01

    The number of stem cells in a colonic crypt is often very small, which leads to large intrinsic fluctuations in the cell population. Based on the model of cell population dynamics with linear feedback in a colonic crypt, we present a stochastic dynamics of the cell population [including stem cells (SCs), transit amplifying cells (TACs), and fully differentiated cells (FDCs)]. The Fano factor, covariance, and susceptibility formulas of the cell population around the steady state are derived by using the Langevin theory. In the range of physiologically reasonable parameter values, it is found that the stationary populations of TACs and FDCs exhibit an approximately threshold behavior as a function of the net growth rate of TACs, and the reproductions of TACs and FDCs can be classified into three regimens: controlled, crossover, and uncontrolled. With the increasing of the net growth rate of TACs, there is a maximum of the relative intrinsic fluctuations (i.e., the Fano factors) of TACs and FDCs in the crossover region. For a fixed differentiation rate and the net growth rate of SCs, the covariance of fluctuations between SCs and TACs has a maximum in the crossover region. However, the susceptibilities of both TACs and FDCs to the net growth rate of TACs have a minimum in the crossover region.

  7. Biosynthesis of intestinal microvillar proteins. Expression of aminopeptidase N along the crypt-villus axis

    DEFF Research Database (Denmark)

    Danielsen, E M

    1984-01-01

    The expression of pig small-intestinal aminopeptidase N (EC 3.4.11.2) along the crypt-villus axis was studied in tangential sections of [35S]-methionine-labelled, organ-cultured explants. The only detectable molecular forms of aminopeptidase N along the crypt-villus axis were polypeptides of Mr 140...

  8. Intestinal crypt homeostasis revealed at single-stem-cell level by in vivo live imaging

    NARCIS (Netherlands)

    Ritsma, Laila; Ellenbroek, Saskia I J; Zomer, Anoek; Snippert, Hugo J; de Sauvage, Frederic J; Simons, Benjamin D; Clevers, Hans; van Rheenen, Jacco

    2014-01-01

    The rapid turnover of the mammalian intestinal epithelium is supported by stem cells located around the base of the crypt. In addition to the Lgr5 marker, intestinal stem cells have been associated with other markers that are expressed heterogeneously within the crypt base region. Previous quantitat

  9. Stem cell self-renewal in intestinal crypt

    Energy Technology Data Exchange (ETDEWEB)

    Simons, Benjamin D., E-mail: bds10@cam.ac.uk [Cavendish Laboratory, Department of Physics, J.J. Thomson Avenue, University of Cambridge, Cambridge CB3 0HE (United Kingdom); The Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN (United Kingdom); Clevers, Hans, E-mail: h.clevers@hubrecht.eu [Hubrecht Institute, KNAW and University Medical Center Utrecht, Uppsalalaan 8, 3584 CT Utrecht (Netherlands)

    2011-11-15

    As a rapidly cycling tissue capable of fast repair and regeneration, the intestinal epithelium has emerged as a favored model system to explore the principles of adult stem cell biology. However, until recently, the identity and characteristics of the stem cell population in both the small intestine and colon has remained the subject of debate. Recent studies based on targeted lineage tracing strategies, combined with the development of an organotypic culture system, have identified the crypt base columnar cell as the intestinal stem cell, and have unveiled the strategy by which the balance between proliferation and differentiation is maintained. These results show that intestinal stem cells operate in a dynamic environment in which frequent and stochastic stem cell loss is compensated by the proliferation of neighboring stem cells. We review the basis of these experimental findings and the insights they offer into the mechanisms of homeostatic stem cell regulation.

  10. Stem cell self-renewal in intestinal crypt

    International Nuclear Information System (INIS)

    As a rapidly cycling tissue capable of fast repair and regeneration, the intestinal epithelium has emerged as a favored model system to explore the principles of adult stem cell biology. However, until recently, the identity and characteristics of the stem cell population in both the small intestine and colon has remained the subject of debate. Recent studies based on targeted lineage tracing strategies, combined with the development of an organotypic culture system, have identified the crypt base columnar cell as the intestinal stem cell, and have unveiled the strategy by which the balance between proliferation and differentiation is maintained. These results show that intestinal stem cells operate in a dynamic environment in which frequent and stochastic stem cell loss is compensated by the proliferation of neighboring stem cells. We review the basis of these experimental findings and the insights they offer into the mechanisms of homeostatic stem cell regulation.

  11. The Carcinogenic Agent Azoxymethane (AOM) Enhances Early Inflammation-induced Colon Crypt Pathology

    DEFF Research Database (Denmark)

    Venning, Freja Albjerg; Claesson, Mogens Helweg; Kissow, Hannelouise

    2013-01-01

    Severe combined immunodeficiency (SCID) mice transplanted with CD4+ T cells depleted of CD25+ regulatory T cells develop colitis within 2-3 weeks after the T cell transfer. In the present study we studied the effect of the carcinogen azoxymethane (AOM) on the colon crypt pathology of normal SCID...... mice and SCID mice with transfer colitis. AOM by itself did result in neither weight loss nor inflammation although treatment affected crypt widths and numbers. Although AOM together with T cell transfer did not increase the level of gut inflammation including COX-2 expression, AOM increased crypt...

  12. Interactive suppression of aberrant crypt foci induced by azoxymethane in rat colon by phytic acid and green tea.

    Science.gov (United States)

    Challa, A; Rao, D R; Reddy, B S

    1997-10-01

    Several epidemiological studies point to a strong correlation between nutrient composition of the diet and cancer of the colon. Phytic acid, present in grains, has been credited with reducing the risk of cancer of the colon. A number of reports are available indicating the benefits of green tea consumption in reducing the risk of stomach, lung and skin cancer, but little data are available on the effect of green tea in reducing the risk of colon cancer. Also, there are no studies on the combined effect of these compounds on colon tumorigenesis. Thus the primary objective of this investigation was to elucidate the combined effects of green tea and phytic acid on colonic preneoplastic lesions and the Phase II enzyme glutathione S-transferase. Fisher 344 male weanling rats were divided into nine groups of 15 rats each and fed the experimental diet for 13 weeks. Rats received two s.c. injections of azoxymethane in saline at 16 mg/kg body wt at 7 and 8 weeks of age. Rats received three levels (0, 1 and 2%) of phytic acid with three levels (0, 1 and 2%) of green tea within each phytic acid level in a 3 x 3 factorial experiment. Results indicate that while green tea had a marginal effect (P green tea and phytic acid was significant (P green tea and phytic acid.

  13. Computational models reveal a passive mechanism for cell migration in the crypt.

    Directory of Open Access Journals (Sweden)

    Sara-Jane Dunn

    Full Text Available Cell migration in the intestinal crypt is essential for the regular renewal of the epithelium, and the continued upward movement of cells is a key characteristic of healthy crypt dynamics. However, the driving force behind this migration is unknown. Possibilities include mitotic pressure, active movement driven by motility cues, or negative pressure arising from cell loss at the crypt collar. It is possible that a combination of factors together coordinate migration. Here, three different computational models are used to provide insight into the mechanisms that underpin cell movement in the crypt, by examining the consequence of eliminating cell division on cell movement. Computational simulations agree with existing experimental results, confirming that migration can continue in the absence of mitosis. Importantly, however, simulations allow us to infer mechanisms that are sufficient to generate cell movement, which is not possible through experimental observation alone. The results produced by the three models agree and suggest that cell loss due to apoptosis and extrusion at the crypt collar relieves cell compression below, allowing cells to expand and move upwards. This finding suggests that future experiments should focus on the role of apoptosis and cell extrusion in controlling cell migration in the crypt.

  14. SMS design and aberration theory

    OpenAIRE

    Corrente, Fabio; Benitez Gimenez, Pablo; Lin WANG; Miñano Dominguez, Juan Carlos; Muñoz, Fernando

    2012-01-01

    The SMS, Simultaneous Multiple Surfaces, design was born to Nonimaging Optics applications and is now being applied also to Imaging Optics. In this paper the wave aberration function of a selected SMS design is studied. It has been found the SMS aberrations can be analyzed with a little set of parameters, sometimes two. The connection of this model with the conventional aberration expansion is also presented. To verify these mathematical model two SMS design systems were raytraced and the dat...

  15. Protection by polaprezinc against radiation-induced apoptosis in rat jejunal crypt cells

    International Nuclear Information System (INIS)

    Polaprezinc, an anti-ulcer drug, is a chelate compound consisting of zinc and L-carnosine. Polaprezinc has been shown to prevent gastric mucosal injury. The anti ulcer effects of polaprezinc have been ascribed to its antioxidative property. The effect of polaprezinc on ionizing radiation-induced apoptosis was studied in the jejunal epithelial crypt cells of rats. Seven-to eight week-old Wistar rats, which were treated with 100 mg/kg of polaprezinc orally 1 h before irradiation or 2% carboxymethyl cellulose sodium in controls, were exposed to whole body X-ray irradiation at 2 Gy. The number of apoptotic cells per jejunum crypt was counted in haematoxylin and eosin stained sections at 0-6 h after irradiation. TdT-mediated dUTP-biotin nick end-labeling (TUNEL) positive cells and immunopositive cells for active caspase-3 per crypt were also counted. Accumulation of p53, p21WAF1/CIP1 and Bax expression in the jejunum after irradiation were examined by Western blot analyses. Polaprezinc treatment given prior to radiation resulted in a significant reduction in numbers of apoptotic cells, TUNEL positive cells and active caspase-3 immunopositive cells in jejunal crypt cells. Polaprezinc treatment resulted in decreases of p53 accumulation, p21WAF1/CIP1 and Bax expression after irradiation. Polaprezinc has a protective effect against ionizing radiation induced apoptosis in rat jejunal crypt cells. (author)

  16. Protection by polaprezinc against radiation-induced apoptosis in rat jejunal crypt cells.

    Science.gov (United States)

    Matsuu-Matsuyama, Mutsumi; Shichijo, Kazuko; Okaichi, Kumio; Nakayama, Toshiyuki; Nakashima, Masahiro; Uemura, Takashi; Niino, Daisuke; Sekine, Ichiro

    2008-07-01

    Polaprezinc, an anti-ulcer drug, is a chelate compound consisting of zinc and L-carnosine. Polaprezinc has been shown to prevent gastric mucosal injury. The anti ulcer effects of polaprezinc have been ascribed to its antioxidative property. The effect of polaprezinc on ionizing radiation-induced apoptosis was studied in the jejunal epithelial crypt cells of rats. Seven-to eight week-old Wistar rats, which were treated with 100 mg/kg of polaprezinc orally 1h before irradiation or 2% carboxymethyl cellulose sodium in controls, were exposed to whole body X-ray irradiation at 2 Gy. The number of apoptotic cells per jejunum crypt was counted in haematoxylin and eosin stained sections at 0-6 h after irradiation. TUNEL positive cells and immunopositive cells for active caspase-3 per crypt were also counted. Accumulation of p53, p21(WAF1/CIP1) and Bax expression in the jejunum after irradiation were examined by Western blot analyses. Polaprezinc treatment given prior to radiation resulted in a significant reduction in numbers of apoptotic cells, TUNEL positive cells and active caspase-3 immunopositive cells in jejunal crypt cells. Polaprezinc treatment resulted in decreases of p53 accumulation, p21(WAF1/CIP1) and Bax expression after irradiation. Polaprezinc has a protective effect against ionizing radiation induced apoptosis in rat jejunal crypt cells. PMID:18413982

  17. Distribution of three microvillar enzymes along the small intestinal crypt-villus axis

    DEFF Research Database (Denmark)

    Hansen, Gert Helge; Niels-Christiansen, L L; Poulsen, M D;

    1994-01-01

    of the axis, whereas ApN is found mainly in the villar and upper crypt enterocytes. All three enzymes are detected in the basolateral membrane at all levels along the crypt-villus axis, although ApN and S-I only occurred at low intensities in the villus region. The microvillar/basolateral labelling...... ratio for the three enzymes increases to a varying degree for the three enzymes along the axis suggesting that the sorting efficiency to the apical membrane improves at least for ApN and S-I as the cells mature. These findings might indicate that the enterocytes change from a transcytotic to a direct......Aminopeptidase N (ApN), dipeptidyl peptidase IV (DPP IV) and sucrose-isomaltase (S-I) are differentially expressed along the pig jejunum crypt-villus axis. Quantitative immunoelectron microscopy and enzyme cytochemistry show that DPP IV and S-I are expressed in enterocytes along the entire length...

  18. Bone marrow hypoplasia and intestinal crypt cell necrosis associated with fenbendazole administration in five painted storks.

    Science.gov (United States)

    Weber, Martha A; Terrell, Scott P; Neiffer, Donald L; Miller, Michele A; Mangold, Barbara J

    2002-08-01

    Five painted storks were treated with fenbendazole for 5 days for internal parasitism. Four birds died following treatment. Profound heteropenia was a consistent finding in all samples evaluated; additionally, the 1 surviving bird had progressive anemia. Consistent necropsy findings in the 4 birds that died were small intestinal crypt cell necrosis and severe bone marrow depletion and necrosis. Fenbendazole has been associated with bone marrow hypoplasia and enteric damage in mammals and other species of birds. The dosages of fenbendazole used in birds are often substantially higher than those recommended for mammals, which may contribute to bone marrow hypoplasia and intestinal crypt cell necrosis associated with fenbendazole administration in birds.

  19. Phase aberration effects in elastography.

    Science.gov (United States)

    Varghese, T; Bilgen, M; Ophir, J

    2001-06-01

    In sonography, phase aberration plays a role in the corruption of sonograms. Phase aberration does not have a significant impact on elastography, if statistically similar phase errors are present in both the pre- and postcompression signals. However, if the phase errors are present in only one of the pre- or postcompression signal pairs, the precision of the strain estimation process will be reduced. In some cases, increased phase errors may occur only in the postcompression signal due to changes in the tissue structure with the applied compression. Phase-aberration effects increase with applied strain and may be viewed as an image quality derating factor, much like frequency-dependent attenuation or undesired lateral tissue motion. In this paper, we present a theoretical and simulation study of the effects of phase aberration on the elastographic strain-estimation process, using the strain filter approach.

  20. Strain difference in jejunal crypt cell susceptibility to radiation-induced apoptosis.

    Science.gov (United States)

    Weil, M M; Stephens, L C; Amos, C I; Ruifrok, A C; Mason, K A

    1996-11-01

    Levels of radiation-induced jejunal crypt cell apoptosis were compared in C57BL/6J, C3Hf/Kam and C3H/HeJ mice. Apoptosis levels were consistently lower in the C3H strains than in C57BL/6J. Although other explanations are possible, the strain difference is most likely to have a genetic basis, and in fact a preliminary analysis of the F2 progeny of C3H/HeJ and C57BL/6J mice indicates that more than one gene is involved. Both C3H strains also had lower levels of radiation-induced thymocyte apoptosis than C57BL/6J mice. Jejunal crypt cell apoptosis levels did not co-segregate with thymocyte apoptosis levels in the F2 progeny of C57BL/6J and C3H/HeJ mice. These results imply that the genes responsible for the difference in radiation-induced thymocyte apoptosis levels between these two strains are not the same as those responsible for the strain difference in radiation-induced jejunal crypt cell apoptosis levels. The experiments reported here identify strain-specific differences in levels of radiation-induced crypt cell apoptosis and are a first step towards identifying genetic polymorphisms that influence sensitivity of the small intestine to damage from ionizing radiation.

  1. The stem cell population of the human colon crypt: analysis via methylation patterns.

    Directory of Open Access Journals (Sweden)

    Pierre Nicolas

    2007-03-01

    Full Text Available The analysis of methylation patterns is a promising approach to investigate the genealogy of cell populations in an organism. In a stem cell-niche scenario, sampled methylation patterns are the stochastic outcome of a complex interplay between niche structural features such as the number of stem cells within a niche and the niche succession time, the methylation/demethylation process, and the randomness due to sampling. As a consequence, methylation pattern studies can reveal niche characteristics but also require appropriate statistical methods. The analysis of methylation patterns sampled from colon crypts is a prototype of such a study. Previous analyses were based on forward simulation of the cell content of the whole crypt and subsequent comparisons between simulated and experimental data using a few statistics as a proxy to summarize the data. In this paper we develop a more powerful method to analyze these data based on coalescent modelling and Bayesian inference. Results support a scenario where the colon crypt is maintained by a high number of stem cells; the posterior indicates a number greater than eight and the posterior mode is between 15 and 20. The results also provide further evidence for synergistic effects in the methylation/demethylation process that could for the first time be quantitatively assessed through their long-term consequences such as the coexistence of hypermethylated and hypomethylated patterns in the same colon crypt.

  2. Draft Genome Sequence of an Oceanobacillus sp. Strain Isolated from Soil in a Burial Crypt

    Science.gov (United States)

    Arizaga, Ylenia; Bikandi, Joseba; Garaizar, Javier; Ganau, Giulia; Paglietti, Bianca; Deligios, Massimo; Rubino, Salvatore

    2016-01-01

    We present the draft genome of an Oceanobacillus sp. strain isolated from spores found in soil samples from a burial crypt of the Cathedral of Sant'Antonio Abate in Castelsardo, Italy. The data obtained indicated the closest relation of the strain with Oceanobacillus caeni. PMID:27469952

  3. Colon stem cell and crypt dynamics exposed by cell lineage reconstruction.

    Directory of Open Access Journals (Sweden)

    Yitzhak Reizel

    2011-07-01

    Full Text Available Stem cell dynamics in vivo are often being studied by lineage tracing methods. Our laboratory has previously developed a retrospective method for reconstructing cell lineage trees from somatic mutations accumulated in microsatellites. This method was applied here to explore different aspects of stem cell dynamics in the mouse colon without the use of stem cell markers. We first demonstrated the reliability of our method for the study of stem cells by confirming previously established facts, and then we addressed open questions. Our findings confirmed that colon crypts are monoclonal and that, throughout adulthood, the process of monoclonal conversion plays a major role in the maintenance of crypts. The absence of immortal strand mechanism in crypts stem cells was validated by the age-dependent accumulation of microsatellite mutations. In addition, we confirmed the positive correlation between physical and lineage proximity of crypts, by showing that the colon is separated into small domains that share a common ancestor. We gained new data demonstrating that colon epithelium is clustered separately from hematopoietic and other cell types, indicating that the colon is constituted of few progenitors and ruling out significant renewal of colonic epithelium from hematopoietic cells during adulthood. Overall, our study demonstrates the reliability of cell lineage reconstruction for the study of stem cell dynamics, and it further addresses open questions in colon stem cells. In addition, this method can be applied to study stem cell dynamics in other systems.

  4. Relationship of DNA lesions and their repair to chromosomal aberration production

    International Nuclear Information System (INIS)

    Recent work on the roles of specific kinds of DNA lesions and their enzymatic repair systems in the production of chromosomal aberrations seems consistent with a simple molecular model of chromosomal aberrations formation. Evidence from experiments with the human repair-deficient genetic diseases xeroderma pigmentosom, ataxia telangiectasia, and Fanconi's anemia is reviewed in the light of the contributions to aberration production of single and double polynucleotide strand breaks, base damage, polynucleotide strand crosslinks, and pyrimidine cyclobutane dimers

  5. Dietary Pectin Increases Intestinal Crypt Stem Cell Survival following Radiation Injury.

    Science.gov (United States)

    Sureban, Sripathi M; May, Randal; Qu, Dongfeng; Chandrakesan, Parthasarathy; Weygant, Nathaniel; Ali, Naushad; Lightfoot, Stan A; Ding, Kai; Umar, Shahid; Schlosser, Michael J; Houchen, Courtney W

    2015-01-01

    Gastrointestinal (GI) mucosal damage is a devastating adverse effect of radiation therapy. We have recently reported that expression of Dclk1, a Tuft cell and tumor stem cell (TSC) marker, 24h after high dose total-body gamma-IR (TBI) can be used as a surrogate marker for crypt survival. Dietary pectin has been demonstrated to possess chemopreventive properties, whereas its radioprotective property has not been studied. The aim of this study was to determine the effects of dietary pectin on ionizing radiation (IR)-induced intestinal stem cell (ISC) deletion, crypt and overall survival following lethal TBI. C57BL/6 mice received a 6% pectin diet and 0.5% pectin drinking water (pre-IR mice received pectin one week before TBI until death; post-IR mice received pectin after TBI until death). Animals were exposed to TBI (14 Gy) and euthanized at 24 and 84h post-IR to assess ISC deletion and crypt survival respectively. Animals were also subjected to overall survival studies following TBI. In pre-IR treatment group, we observed a three-fold increase in ISC/crypt survival, a two-fold increase in Dclk1+ stem cells, increased overall survival (median 10d vs. 7d), and increased expression of Dclk1, Msi1, Lgr5, Bmi1, and Notch1 (in small intestine) post-TBI in pectin treated mice compared to controls. We also observed increased survival of mice treated with pectin (post-IR) compared to controls. Dietary pectin is a radioprotective agent; prevents IR-induced deletion of potential reserve ISCs; facilitates crypt regeneration; and ultimately promotes overall survival. Given the anti-cancer activity of pectin, our data support a potential role for dietary pectin as an agent that can be administered to patients receiving radiation therapy to protect against radiation-induces mucositis.

  6. Dietary regulation and localization of apoptosis cascade proteins in the colonic crypt.

    Science.gov (United States)

    Avivi-Green, C; Polak-Charcon, S; Madar, Z; Schwartz, B

    2000-02-01

    This study was designed primarily to assess the localization of apoptosis cascade proteins along the rat colonic crypt and secondarily to test whether the activity and/or localization of these proteins are affected by the enrichment of the diet with the soluble fiber pectin. Expression of apoptosis cascade proteins was assessed in isolated colonocytes harvested from the luminal and basal crypt colonocyte populations. Two different dietary regimens were tested: a standard diet (diet A), and a diet enriched in pectin (diet B), a soluble fiber that undergoes fermentation in the cecum and produces high concentrations of intracolonic short-chain fatty acids. Caspase-1 expression was maximal in luminal colonocytes of rats fed diet B, as evidenced by Western blot and immunohistological analyses. Expression of the cleaved poly(ADP-ribose) polymerase product was elevated in both the luminal and basal colonocytes of the pectin-fed group, whereas in rats fed diet A, the expression was lower, especially in basal crypt colonocytes. The highest expression of the antiapoptotic protein Bcl-2 was observed in the lower compartments of the colonic crypt tissue and was maximal in the rat group fed a standard diet. The apoptotic index in colonocytes of rats fed diet B was higher than that measured in rats fed diet A. Cumulatively, our results indicate that apoptosis cascade proteins are differentially localized along the lumen-crypt axis, and their expression and activity may be controlled by dietary components. These results may, at least partially, account for the documented protective effect of butyrogenic fibers on colorectal cancer. PMID:10679813

  7. Study of the wavefront aberrations in children with amblyopia

    Institute of Scientific and Technical Information of China (English)

    ZHAO Peng-fei; ZHOU Yue-hua; WANG Ning-li; ZHANG Jing

    2010-01-01

    Background Amblyopia is a common ophthalmological condition and the wavefront aberrometer is a relatively new diagnostic tool used globally to measure optical characteristics of human eyes as well as to study refractive errors in amblyopic eyes. We studied the wavefront aberration of the amblyopic children's eyes and analyzed the mechanism of the wavefront aberration in the formation of the amblyopia, try to investigate the new evidence of the treatment of the amblyopia, especially in the refractory amblyopia.Methods The WaveScan Wavefront System (VISX, USA) aberrometer was used to investigate four groups of children under dark accommodation and cilliary muscle paralysis. There were 45 cases in the metropic group, 87 in the amblyopic group, 92 in the corrected-amblyopic group and 38 in the refractory amblyopic group. One-way analysis of variance (ANOVA), t-test and multivariate linear regression were used to analyze all the data.Results Third order to 6th order aberrations showed a decreasing trend whereas in the higher order aberrations the main ones were 3rd order coma (Z3-1-Z31), trefoil (Z3-3-Z33) and 4th order aberration (Z40); and 3rd order coma represented the highest percentage of all three main aberrations. Within 3rd order coma, vertical coma (Z3-1) accounted for a greater percentage than horizontal coma (Z31). Significant differences of vertical coma were found among all clinical groups of children: vertical coma in the amblyopic group (0.17±0.15) was significantly higher than in the metropic group (0.11±0.13, P0.05).Conclusions Although lower order aberrations such as defocus (myopia and hyperopia) and astigmatism are major factors determining the quality of the retinal image, higher order aberrations also need to be considered in amblyopic eyes as their effects are significant.

  8. DNA Repair Defects and Chromosomal Aberrations

    Science.gov (United States)

    Hada, Megumi; George, K. A.; Huff, J. L.; Pluth, J. M.; Cucinotta, F. A.

    2009-01-01

    Yields of chromosome aberrations were assessed in cells deficient in DNA doublestrand break (DSB) repair, after exposure to acute or to low-dose-rate (0.018 Gy/hr) gamma rays or acute high LET iron nuclei. We studied several cell lines including fibroblasts deficient in ATM (ataxia telangiectasia mutated; product of the gene that is mutated in ataxia telangiectasia patients) or NBS (nibrin; product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase (DNA-PK) activity. Chromosomes were analyzed using the fluorescence in situ hybridization (FISH) chromosome painting method in cells at the first division post irradiation, and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving >2 breaks in 2 or more chromosomes). Gamma irradiation induced greater yields of both simple and complex exchanges in the DSB repair-defective cells than in the normal cells. The quadratic dose-response terms for both simple and complex chromosome exchanges were significantly higher for the ATM- and NBS-deficient lines than for normal fibroblasts. However, in the NBS cells the linear dose-response term was significantly higher only for simple exchanges. The large increases in the quadratic dose-response terms in these repair-defective cell lines points the importance of the functions of ATM and NBS in chromatin modifications to facilitate correct DSB repair and minimize the formation of aberrations. The differences found between ATM- and NBS-deficient cells at low doses suggest that important questions should with regard to applying observations of radiation sensitivity at high dose to low-dose exposures. For aberrations induced by iron nuclei, regression models preferred purely linear dose responses for simple exchanges and quadratic dose responses for complex exchanges. Relative biological effectiveness (RBE) factors of all of

  9. A theoretical investigation of the effect of proliferation and adhesion on monoclonal conversion in the colonic crypt

    KAUST Repository

    Mirams, Gary R.

    2012-11-01

    The surface epithelium lining the intestinal tract renews itself rapidly by a coordinated programme of cell proliferation, migration and differentiation events that is initiated in the crypts of Lieberkühn. It is generally believed that colorectal cancer arises due to mutations that disrupt the normal cellular dynamics of the crypts. Using a spatially structured cell-based model of a colonic crypt, we investigate the likelihood that the progeny of a mutated cell will dominate, or be sloughed out of, a crypt. Our approach is to perform multiple simulations, varying the spatial location of the initial mutation, and the proliferative and adhesive properties of the mutant cells, to obtain statistical distributions for the probability of their domination. Our simulations lead us to make a number of predictions. The process of monoclonal conversion always occurs, and does not require that the cell which initially gave rise to the population remains in the crypt. Mutations occurring more than one to two cells from the base of the crypt are unlikely to become the dominant clone. The probability of a mutant clone persisting in the crypt is sensitive to dysregulation of adhesion. By comparing simulation results with those from a simple one-dimensional stochastic model of population dynamics at the base of the crypt, we infer that this sensitivity is due to direct competition between wild-type and mutant cells at the base of the crypt. We also predict that increases in the extent of the spatial domain in which the mutant cells proliferate can give rise to counter-intuitive, non-linear changes to the probability of their fixation, due to effects that cannot be captured in simpler models. © 2012 Elsevier Ltd.

  10. Radioprotection of the intestinal crypts of mice by recombinant human interleukin-1 alpha

    International Nuclear Information System (INIS)

    Recombinant human interleukin-1 alpha (rHIL-1 alpha or IL-1) protected the intestinal crypt cells of mice against X-ray-induced damage. The survival of crypt cells measured in terms of their ability to form colonies of regenerating duodenal epithelium in situ was increased when IL-1 was given either before or after irradiation. The maximum degree of radioprotection was seen when the drug was given between 13 and 25 h before irradiation. The IL-1 dose producing maximum protection was about 6.3 micrograms/kg. This is the first report indicating that the cytokine IL-1 has a radioprotective effect in the intestine. The finding suggests that IL-1 may be of potential value in preventing radiation injury to the gut in the clinic

  11. Modelling the spatio-temporal cell dynamics reveals novel insights on cell differentiation and proliferation in the small intestinal crypt.

    Directory of Open Access Journals (Sweden)

    Carmen Pin

    Full Text Available We developed a slow structural relaxation model to describe cellular dynamics in the crypt of the mouse small intestine. Cells are arranged in a three dimensional spiral the size of which dynamically changes according to cell production demands of adjacent villi. Cell differentiation and proliferation is regulated through Wnt and Notch signals, the strength of which depends on the local cell composition. The highest level of Wnt activity is associated with maintaining equipotent stem cells (SC, Paneth cells and common goblet-Paneth cell progenitors (CGPCPs intermingling at the crypt bottom. Low levels of Wnt signalling area are associated with stem cells giving rise to secretory cells (CGPCPs, enteroendocrine or Tuft cells and proliferative absorptive progenitors. Deciding between these two fates, secretory and stem/absorptive cells, depends on Notch signalling. Our model predicts that Notch signalling inhibits secretory fate if more than 50% of cells they are in contact with belong to the secretory lineage. CGPCPs under high Wnt signalling will differentiate into Paneth cells while those migrating out from the crypt bottom differentiate into goblet cells. We have assumed that mature Paneth cells migrating upwards undergo anoikis. Structural relaxation explains the localisation of Paneth cells to the crypt bottom in the absence of active forces. The predicted crypt generation time from one SC is 4-5 days with 10-12 days needed to reach a structural steady state. Our predictions are consistent with experimental observations made under altered Wnt and Notch signalling. Mutations affecting stem cells located at the crypt floor have a 50% chance of being propagated throughout the crypt while mutations in cells above are rarely propagated. The predicted recovery time of an injured crypt losing half of its cells is approximately 2 days.

  12. The effect of ginkgo biloba extract on radiosensitivity of mouse skin and jejunal crypt

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Kyung Hwan; Ha, Sung Whan [Seoul National Univ. Medical College, Seoul (Korea, Republic of)

    1998-06-01

    Ginkgo biloba extract(GBE) is known to increase the peripheral blood circulation. This study was designed to evaluate the effect of GBE on the acute normal tissue radiation reaction. C3H mice were divided into two groups, radiation alone and two doses GBE plus radiation, for both acute skin reaction and jejunal crypt assay. GBE was given i.p. one hour before irradiation with priming dose given one day earlier. Thirty to Fifty Gy for acute skin reaction and 11 to 14 Gy for jejunal crypt were irradiated to right hind leg and whole body, respectively. Radiation doses(RD{sub 50}) for peak skin score of 2.0 were 44.2Gy(40.6-48.2Gy) for radiation alone and 44.4Gy(41.6-47.4Gy) for two doses GBE plus radiation, showing no effect of GBE on acute radiation skin damage. The numbers of regenerating jejunal crypts per circumference were also almost the same for each radiation dose level(p=0.57-0.94), and the mean lethal doses(D{sub o}) were 1.80Gy(1.57-2.09Gy) for radiation alone and 1.88Gy(1.65-2.18Gy) for two doses GBE plus radiation, indicating no effect of GBE on jejunal crypt cell survival after radiation. GBE doesn't increase acute normal tissue radiation reaction in this model system. As GBE was verified to enhance radiation effect on tumor, high therapeutic gain is expected when GBE is combined with radiation therapy.

  13. The effect of ginkgo biloba extract on radiosensitivity of mouse skin and jejunal crypt

    International Nuclear Information System (INIS)

    Ginkgo biloba extract(GBE) is known to increase the peripheral blood circulation. This study was designed to evaluate the effect of GBE on the acute normal tissue radiation reaction. C3H mice were divided into two groups, radiation alone and two doses GBE plus radiation, for both acute skin reaction and jejunal crypt assay. GBE was given i.p. one hour before irradiation with priming dose given one day earlier. Thirty to Fifty Gy for acute skin reaction and 11 to 14 Gy for jejunal crypt were irradiated to right hind leg and whole body, respectively. Radiation doses(RD50) for peak skin score of 2.0 were 44.2Gy(40.6-48.2Gy) for radiation alone and 44.4Gy(41.6-47.4Gy) for two doses GBE plus radiation, showing no effect of GBE on acute radiation skin damage. The numbers of regenerating jejunal crypts per circumference were also almost the same for each radiation dose level(p=0.57-0.94), and the mean lethal doses(Do) were 1.80Gy(1.57-2.09Gy) for radiation alone and 1.88Gy(1.65-2.18Gy) for two doses GBE plus radiation, indicating no effect of GBE on jejunal crypt cell survival after radiation. GBE doesn't increase acute normal tissue radiation reaction in this model system. As GBE was verified to enhance radiation effect on tumor, high therapeutic gain is expected when GBE is combined with radiation therapy

  14. Notch signaling modulates proliferation and differentiation of intestinal crypt base columnar stem cells

    OpenAIRE

    VanDussen, Kelli L; Carulli, Alexis J.; Keeley, Theresa M.; Patel, Sanjeevkumar R.; Puthoff, Brent J.; Magness, Scott T.; Tran, Ivy T.; Maillard, Ivan; Siebel, Christian; Kolterud, Åsa; Grosse, Ann S.; Gumucio, Deborah L; Ernst, Stephen A.; Tsai, Yu-Hwai; Dempsey, Peter J.

    2012-01-01

    Notch signaling is known to regulate the proliferation and differentiation of intestinal stem and progenitor cells; however, direct cellular targets and specific functions of Notch signals had not been identified. We show here in mice that Notch directly targets the crypt base columnar (CBC) cell to maintain stem cell activity. Notch inhibition induced rapid CBC cell loss, with reduced proliferation, apoptotic cell death and reduced efficiency of organoid initiation. Furthermore, expression o...

  15. Energy metabolism in intestinal epithelial cells during maturation along the crypt-villus axis

    Science.gov (United States)

    Yang, Huansheng; Wang, Xiaocheng; Xiong, Xia; Yin, Yulong

    2016-01-01

    Intestinal epithelial cells continuously migrate and mature along crypt-villus axis (CVA), while the changes in energy metabolism during maturation are unclear in neonates. The present study was conducted to test the hypothesis that the energy metabolism in intestinal epithelial cells would be changed during maturation along CVA in neonates. Eight 21-day-old suckling piglets were used. Intestinal epithelial cells were isolated sequentially along CVA, and proteomics was used to analyze the changes in proteins expression in epithelial cells along CVA. The identified differentially expressed proteins were mainly involved in cellular process, metabolic process, biological regulation, pigmentation, multicellular organizational process and so on. The energy metabolism in intestinal epithelial cells of piglets was increased from the bottom of crypt to the top of villi. Moreover, the expression of proteins related to the metabolism of glucose, most of amino acids, and fatty acids was increased in intestinal epithelial cells during maturation along CVA, while the expression of proteins related to glutamine metabolism was decreased from crypt to villus tip. The expression of proteins involved in citrate cycle was also increased intestinal epithelial cells during maturation along CVA. Moreover, dietary supplementation with different energy sources had different effects on intestinal structure of weaned piglets. PMID:27558220

  16. Inhibition of Notch signaling reduces the number of surviving Dclk1+ reserve crypt epithelial stem cells following radiation injury.

    Science.gov (United States)

    Qu, Dongfeng; May, Randal; Sureban, Sripathi M; Weygant, Nathaniel; Chandrakesan, Parthasarathy; Ali, Naushad; Li, Linheng; Barrett, Terrence; Houchen, Courtney W

    2014-03-01

    We have previously reported that doublecortin-like kinase 1 (Dclk1) is a putative intestinal stem cell (ISC) marker. In this report, we evaluated the use of Dclk1 as a marker of surviving ISCs in response to treatment with high-dose total body irradiation (TBI). Both apoptotic and mitotic Dclk1(+) cells were observed 24 h post-TBI associated with a corresponding loss of intestinal crypts observed at 84 h post-TBI. Although the Notch signaling pathway plays an important role in regulating proliferation and lineage commitment within the intestine, its role in ISC function in response to severe genotoxic injury is not yet fully understood. We employed the microcolony assay to functionally assess the effects of Notch inhibition with difluorophenacetyl-l-alanyl-S-phenylglycine t-butyl ester (DAPT) on intestinal crypt stem cell survival following severe (>8 Gy) radiation injury. Following treatment with DAPT, we observed a nearly 50% reduction in the number of surviving Dclk1(+) crypt epithelial cells at 24 h after TBI and similar reduction in the number of surviving small intestinal crypts at 84 h. These data indicate that inhibition of Notch signaling decreases ISC survival following radiation injury, suggesting that the Notch signaling pathway plays an important role in ISC-mediated crypt regeneration. These results also suggest that crypt epithelial cell Dclk1 expression can be used as one potential marker to evaluate the early survival of ISCs following severe radiation injury.

  17. Quantitative analysis of crypt cell population during postnatal development of the olfactory organ of the guppy, Poecilia reticulata (Teleostei, Poecilidae), from birth to sexual maturity.

    Science.gov (United States)

    Bettini, Simone; Lazzari, Maurizio; Franceschini, Valeria

    2012-08-01

    Crypt cells are one of three types of olfactory sensory neuron, differing from ciliated and microvillar cells in shape, localization and number, and found only in fish. Although crypt cells are morphologically well characterized, their function remains unclear. They were hypothesized to be involved in reproductive behaviours by detecting sex pheromones, but electrophysiological investigations revealed sensitivity to only amino acids. However, the number of crypt cells in adult guppies is not the same in the two sexes. In this study, we compared the size of the crypt cell population in juvenile guppies during the first 90 days after birth. The purpose of our study was to clarify whether a correlation exists between sex and the number of these olfactory neurons. The data show that guppies reach adult crypt cell density when they become sexually mature. Despite a constant increment in volume during development of the olfactory organ, the minimum density of crypt neurons occurs at ~45 days. Moreover, in the early weeks, the density of crypt neurons is greater in males than in females because in females the total number of cells decreases significantly after just 7 days. In adults, however, crypt neurons are found in higher density in females than in males. These findings suggest that the number of crypt cells is sex specific, with independent developmental dynamics between males and females. A role in pheromone detection could explain such a difference, but the early appearance of crypt cells in the first days of life is suggestive of other, not sexually related, functions.

  18. Phase Aberrations in Diffraction Microscopy

    CERN Document Server

    Marchesini, S; Barty, A; Cui, C; Howells, M R; Spence, J C H; Weierstall, U; Minor, A M

    2005-01-01

    In coherent X-ray diffraction microscopy the diffraction pattern generated by a sample illuminated with coherent x-rays is recorded, and a computer algorithm recovers the unmeasured phases to synthesize an image. By avoiding the use of a lens the resolution is limited, in principle, only by the largest scattering angles recorded. However, the imaging task is shifted from the experiment to the computer, and the algorithm's ability to recover meaningful images in the presence of noise and limited prior knowledge may produce aberrations in the reconstructed image. We analyze the low order aberrations produced by our phase retrieval algorithms. We present two methods to improve the accuracy and stability of reconstructions.

  19. Aberrant methylation patterns in cancer

    OpenAIRE

    Hudler, Petra; Videtič, Alja

    2016-01-01

    Epigenetic mechanisms, such as DNA methylation, DNA hydroxymethylation, post-translational modifications (PTMs) of histone proteins affecting nucleosome remodelling, and regulation by small and large non-coding RNAs (ncRNAs) work in concert with cis and trans acting elements to drive appropriate gene expression. Advances in detection methods and development of dedicated platforms and methylation arrays resulted in an explo - sion of information on aberrantly methylated sequences linking devia...

  20. Aberrant angiogenesis: The gateway to diabetic complications

    Directory of Open Access Journals (Sweden)

    Sunil K Kota

    2012-01-01

    Full Text Available Diabetes Mellitus is a metabolic cum vascular syndrome with resultant abnormalities in both micro- and macrovasculature. The adverse long-term effects of diabetes mellitus have been described to involve many organ systems. Apart from hyperglycemia, abnormalities of angiogenesis may cause or contribute toward many of the clinical manifestations of diabetes. These are implicated in the pathogenesis of vascular abnormalities of the retina, kidneys, and fetus, impaired wound healing, increased risk of rejection of transplanted organs, and impaired formation of coronary collaterals. A perplexing feature of the aberrant angiogenesis is that excessive and insufficient angiogenesis can occur in different organs in the same individual. The current article hereby reviews the molecular mechanisms including abnormalities in growth factors, cytokines, and metabolic derangements, clinical implications, and therapeutic options of dealing with abnormal angiogenesis in diabetes.

  1. The formation of an aberrant PAX5 transcript in a patient with mixed phenotype acute leukemia harboring der(9t(7;9(q11.2;p13

    Directory of Open Access Journals (Sweden)

    Jun Amaki

    2016-01-01

    Full Text Available We experienced the case of a 56-year-old male with B-lymphoid/myeloid lineage mixed phenotype acute leukemia (MPAL. A cytogenetic analysis of the patient's bone marrow revealed a complex karyotype, including der(9t(7;9(q11.2;p13. We identified an aberrant PAX5 transcript, including the exons 1A to 5 and the contiguous intron 5/6 sequence using the 3′ rapid amplification of cDNA ends-polymerase chain reaction method, and confirmed their expression in the leukemic cells. Our case suggests that der(9t(7;9(q11.2;p13 can cause the truncation of the PAX5 transcript, which is supposed to contribute to the generation of MPAL, in addition to three previously reported types of PAX5 fusion.

  2. Fructo-oligosaccharides and iron bioavailability in anaemic rats: the effects on iron species distribution, ferroportin-1 expression, crypt bifurcation and crypt cell proliferation in the caecum.

    Science.gov (United States)

    Lobo, Alexandre R; Gaievski, Eduardo H S; De Carli, Eduardo; Alvares, Eliana P; Colli, Célia

    2014-10-28

    The present study investigated the effects of fructo-oligosaccharides (FOS) on the bioavailability of Fe from ferric pyrophosphate (FP), a water-insoluble compound, in Fe-deficient anaemic rats that were subjected to a Hb repletion assay. Male Wistar rats (n 64) were fed adequate or low (8 mg/kg) Fe diets for 15 d followed by 1 or 2 weeks of Fe repletion with diets providing 35 mg Fe/kg as ferrous sulphate (FS), FP or FP that was mixed with 7·5% FOS in the form of yacon flour or Raftilose P95 (RAF), a purified source of FOS. The effects of FOS were observed within the 1st week of the repletion period. Fe bioavailability was improved by FOS supplementation, as measured by Hb regeneration efficiency and hepatic Fe stores, which were more pronounced in the RAF group. Moreover, RAF supplementation resulted in a higher biological value relative to that of the FP group. FOS supplementation resulted in caecal enlargement, in addition to acidification and Fe species redistribution in the caecal contents relative to the control rats. These effects occurred concomitantly with decreased ferroportin (FPN)-1 expression in the caecal mucosa, which was similar in magnitude to that observed in the FS group. Caecum mucosal morphometry was influenced by FOS supplementation, whereas crypt fission and cell proliferation were highest in the caecum of the RAF group. These results reinforce the effects of FOS as Fe bioavailability enhancers in anaemic rats that are sustained by early changes in their caecal environment (decreased mucosal FPN-1 expression and increased Fe absorbability, crypt fission and cellularity). PMID:25192308

  3. Effect of etoricoxib, a cyclooxygenase-2 selective inhibitor on aberrant crypt formation and apoptosis in 1,2 dimethyl hydrazine induced colon carcinogenesis in rat model Efecto del etoricoxib, un inhibidor selectivo de la ciclooxigenasa-2, sobre la formación de criptas aberrantes y la apoptosis en un modelo murino de carcinogénesis de colon inducidad por 1,2-dimetilhidracina

    OpenAIRE

    Sharma, P.; J Kaur; S. N. Sanyal

    2010-01-01

    Etoricoxib, a second generation selective cyclooxygenase-2 (COX-2) inhibitor had been studied for the chemopreventive response at its therapeutic anti-inflammatory dose in 1,2-dimethylhydrazine (DMH) induced colon carcinogenesis in rat model. Eight to ten weeks old male rats of Sprague-Dawley strain were divided into four groups. While group 1 served as control and received the vehicle of the drugs, group 2 and 3 were administered freshly prepared DMH in 1mM EDTA-saline (pH 7.0) (30 mg/kg bod...

  4. Diagnostic of the conservation state in the crypt of the Abbey of Montecorona: biological, microclimatic and geophysical evaluations

    Science.gov (United States)

    Cataldo, Rosella; Leucci, Giovanni; Siviero, Stefano; Pagiotti, Rita; Angelini, Paola

    2009-09-01

    The Abbey S Salvatore of Montecorona, an important Benedictine monastary of the eleventh century, is placed at Umbertide, on the Northwest of Perugia (Italy). The site is in the Umbria region, characterized by a well-documented historical and instrumental seismicity, which periodically exposes this area to hazards with widespread damage for the population and the built-up environment. This paper focused on the study of the conservation state of the crypt of the Abbey. A multidisciplinary approach, using biological and physical non-destructive methods, is proposed. First, we investigated the microbial biodiversity of the crypt, analysing the presence of microorganisms by microscopic and cultivation methods. The second step was the study of the influence of the environment on the colonization and growth of these microorganisms, with a continuous monitoring of the microclimate inside the crypt, especially the thermo-hygrometric conditions. Moreover, with the aims of localizing the structures involved in the deterioration process, such as fractures, moisture, etc, ground penetrating radar (GPR) surveys, with different methodologies, were carried out in the crypt: reflection mode on the floor and traveltime tomography on the ceiling. From GPR data, a structure of archaeological interest was evidenced and, by means of a frequency signal analysis, the underground water content of the stone was also evaluated, assessing the correlation between the spectral content and moisture degree. The integration of information from these different methods provided some interesting results, also addressing possible interventions for protection and conservation of the crypt.

  5. Hierarchy and plasticity in the crypt: back to the drawing board

    Institute of Scientific and Technical Information of China (English)

    Catherine Legraverend; Philippe Jay

    2011-01-01

    The prevailing concept in the field of stem cell research is that of a multipotent self-renewing cell,positioned at the origin of a hierarchical tree of branching specificities,increasing maturity and decreasing self-renewal ability.In the epithelium of the small intestine,until very recently,the supra-Paneth crypt base columnar (CBC) cell position +4(cp4) (counting from the bottom of the crypt) was widely assumed to be the preferred position of multipotent stem cells [1,2].Yet electron microscopy,as well as autoradiography and lineage tracing studies,supported the presence of undifferentiated [3],actively cycling [4],multipotent CBC stem cells located between Paneth cells in the crypt [5-7].Based on the results of expression and lineage studies with Lgr5-EGFP-IRES-CreERT2 knock-in mice and Rosa26-LacZ reporter mice,it was possible to show that multipotent CBC cells expressing the Lgr5 orphan receptor are present throughout the gastro-intestinal tract [7].But they are not alone.Another recent lineage study revealed the existence of multipotent,self-renewing Lgr5- CBC cells expressing the Bmi1 proto-oncogene and preferentially located above the highest Paneth cell [8].This discovery brought the cp4 model back under the spotlight,and subsequent expression studies revealed a partial overlap between the Lgr5+ and Bmi1+ CBC cell populations [9].In a recent issue of Nature,Huan Tian and colleagues now tackle the issue of their contribution to the turnover of the intestinal epithelium [10].

  6. Differences in Radiation Dose Response between Small and Large Intestinal Crypts.

    Science.gov (United States)

    Otsuka, Kensuke; Suzuki, Keiji

    2016-09-01

    The protection of intestinal epithelial cells from the lethal effects induced by high-dose radiation is an important issue in radiotherapy and in the treatment of acute radiation syndrome. However, the effects of middle- and low-dose radiation on intestinal epithelial cells remain unclear. Because the accumulation of DNA damage in intestinal stem cells may be crucial for the development of cancer-initiating cells, it is important to understand the kinetics of DNA repair and tissue response (which are involved in the elimination of damaged cells and tissue injury repair) to middle- to low-dose irradiation. In this study, mice were X-ray irradiated with 0.1, 1 or 4 Gy, after which the small intestine (duodenum and ileum) and colon were harvested from the animals. DNA damage repair and the elimination of damaged cells were quantified by measuring the number of foci of 53BP1, a surrogate marker for DNA double-strand breaks. Tissue-proliferative response was evaluated by determining the number of Ki-67(+) and mitotic cells. Intra-crypt response differed considerably between the small intestine and the colon. In the small intestine, 53BP1 foci were detected immediately after irradiation, but rapidly disappeared thereafter, especially noticeable in Lgr5(+) stem cells. Cellular growth was temporally arrested; however, cell numbers and mitotic cell numbers in the crypt did not change. The kinetics of DNA damage repair in Lgr5(+) stem cells were similar to those in the small intestines, while the colon was more susceptible to radiation-induced damage. Preferential cell loss in the lower crypt was clearly observed in the colon; and after low-dose X-ray irradiation, only the colon exhibited considerably reduced cell numbers and dramatic induction of mitosis. These results suggest that differences in radiation dose response between the small and the large intestine may depend on the growth activity of stem cells after DNA repair. PMID:27556352

  7. Regulation of Ceramide Synthase-Mediated Crypt Epithelium Apoptosis by DNA Damage Repair Enzymes

    Science.gov (United States)

    Rotolo, Jimmy A.; Mesicek, Judith; Maj, Jerzy; Truman, Jean-Philip; Haimovitz-Friedman, Adriana; Kolesnick, Richard; Fuks, Zvi

    2015-01-01

    Acute endothelial cell apoptosis and microvascular compromise couple GI tract irradiation to reproductive death of intestinal crypt stem cell clonogens (SCCs) following high-dose radiation. Genetic or pharmacologic inhibition of endothelial apoptosis prevents intestinal damage, but as the radiation dose is escalated, SCCs become directly susceptible to an alternate cell death mechanism, mediated via ceramide synthase (CS)-stimulated de novo synthesis of the pro-apoptotic sphingolipid ceramide, and p53-independent apoptosis of crypt SCCs. We previously reported that ATM deficiency resets the primary radiation lethal pathway, allowing CS-mediated apoptosis at the low-dose range of radiation. The mechanism for this event, termed target reordering, remains unknown. Here we show that inactivation of DNA damage repair pathways signal CS-mediated apoptosis in crypt SCCs, presumably via persistent unrepaired DNA double strand breaks (DSBs). Genetic loss-of-function of sensors and transducers of DNA DSB repair confers the CS-mediated lethal pathway in intestines of sv129/B6Mre11ATLD1/ATLD1 and C57BL/6Prkdc/SCID (SCID) mice exposed to low-dose radiation. In contrast, CS-mediated SCC lethality was mitigated in irradiated gain-of-function Rad50S/S mice, and epistasis studies order Rad50 upstream of Mre11. These studies suggest unrepaired DNA DSBs as causative in target re-ordering in intestinal SCCs. As such, we provide an in vivo model of DNA damage repair that is standardized, can be exploited to understand allele-specific regulation in intact tissue, and is pharmacologically tractable. PMID:20086180

  8. Survival of intestinal crypt cells after exposure to high Z, high energy charged particles

    International Nuclear Information System (INIS)

    The purpose of the experiments described is to evaluate the relative biological effectiveness (RBE) of high energy charged particles for cell killing in the mouse crypt-cell survival assay. The reference radiation, 225 kVp x rays, is slightly more effective than plateau helium ions. For carbon, neon and argon ions there is a suggestion of a saturation effect with increasing LET. Furthermore, it should be emphasized that there is a large difference associated with particles of different atomic number or mass at the same average LET

  9. Atom lens without chromatic aberrations

    CERN Document Server

    Efremov, Maxim A; Schleich, Wolfgang P

    2012-01-01

    We propose a lens for atoms with reduced chromatic aberrations and calculate its focal length and spot size. In our scheme a two-level atom interacts with a near-resonant standing light wave formed by two running waves of slightly different wave vectors, and a far-detuned running wave propagating perpendicular to the standing wave. We show that within the Raman-Nath approximation and for an adiabatically slow atom-light interaction, the phase acquired by the atom is independent of the incident atomic velocity.

  10. Chromosome aberrations induced in human lymphocytes by neutron irradiation

    International Nuclear Information System (INIS)

    In vitro dose-response curves of unstable chromosome aberrations in human lymphocytes have been obtained for neutron spectra of mean energies 0.7, 0.9, 7.6 and 14.7 MeV. The aberration yields have been fitted to the quadratic function Y = αD + βD2, which is consistent with the single-track and two-track model of aberration formation. However with high-LET radiation, the linear component of yield, corresponding to damage caused by single tracks, predominates, and this term becomes more dominant with increasing LET, so that for fission spectrum neutrons the relationship is linear, Y = αD. At low doses, such as those received by radiation workers, limiting r.b.e. values between 13 and 47 were obtained relative to 60Co γ-radiation. At higher doses, as used in radiotherapy, the values were much lower; ranging from 2.7 to 8 at 200 rad of equivalent γ-radiation. Both sets of r.b.e. values correlated well with track-averaged LET but not with dose-averaged LET. When the numbers of cells without aberrations were plotted against radiation dose, curves were obtained which are similar in shape to those for conventional cell-survival experiments with comparable neutron spectra. The D0 values obtained in the present study are close to those from other cell systems. (author)

  11. Impaired Cell Volume Regulation in Intestinal Crypt Epithelia of Cystic Fibrosis Mice

    Science.gov (United States)

    Valverde, M. A.; O'Brien, J. A.; Sepulveda, F. V.; Ratcliff, R. A.; Evans, M. J.; Colledge, W. H.

    1995-09-01

    Cystic fibrosis is a disease characterized by abnormalities in the epithelia of the lungs, intestine, salivary and sweat glands, liver, and reproductive systems, often as a result of inadequate hydration of their secretions. The primary defect in cystic fibrosis is the altered activity of a cAMP-activated Cl^- channel, the cystic fibrosis transmembrane conductance regulator (CFTR) channel. However, it is not clear how a defect in the CFTR Cl^- channel function leads to the observed pathological changes. Although much is known about the structural properties and regulation of the CFTR, little is known of its relationship to cellular functions other than the cAMP-dependent Cl^- secretion. Here we report that cell volume regulation after hypotonic challenge is also defective in intestinal crypt epithelial cells isolated from CFTR -/- mutant mice. Moreover, the impairment of the regulatory volume decrease in CFTR -/- crypts appears to be related to the inability of a K^+ conductance to provide a pathway for the exit of this cation during the volume adjustments. This provides evidence that the lack of CFTR protein may have additional consequences for the cellular function other than the abnormal cAMP-mediated Cl^- secretion.

  12. Phylogenetically Diverse Burkholderia Associated with Midgut Crypts of Spurge Bugs, Dicranocephalus spp. (Heteroptera: Stenocephalidae).

    Science.gov (United States)

    Kuechler, Stefan Martin; Matsuura, Yu; Dettner, Konrad; Kikuchi, Yoshitomo

    2016-06-25

    Diverse phytophagous heteropteran insects, commonly known as stinkbugs, are associated with specific gut symbiotic bacteria, which have been found in midgut cryptic spaces. Recent studies have revealed that members of the stinkbug families Coreidae and Alydidae of the superfamily Coreoidea are consistently associated with a specific group of the betaproteobacterial genus Burkholderia, called the "stinkbug-associated beneficial and environmental (SBE)" group, and horizontally acquire specific symbionts from the environment every generation. However, the symbiotic system of another coreoid family, Stenocephalidae remains undetermined. We herein investigated four species of the stenocephalid genus Dicranocephalus. Examinations via fluorescence in situ hybridization (FISH) and transmission electron microscopy (TEM) revealed the typical arrangement and ultrastructures of midgut crypts and gut symbionts. Cloning and molecular phylogenetic analyses of bacterial genes showed that the midgut crypts of all species are colonized by Burkholderia strains, which were further assigned to different subgroups of the genus Burkholderia. In addition to the SBE-group Burkholderia, a number of stenocephalid symbionts belonged to a novel clade containing B. sordidicola and B. udeis, suggesting a specific symbiont clade for the Stenocephalidae. The symbiotic systems of stenocephalid bugs may provide a unique opportunity to study the ongoing evolution of symbiont associations in the stinkbug-Burkholderia interaction. PMID:27265344

  13. Identification of a Developmental Gene Expression Signature, Including HOX Genes, for the Normal Human Colonic Crypt Stem Cell Niche: Overexpression of the Signature Parallels Stem Cell Overpopulation During Colon Tumorigenesis

    OpenAIRE

    Bhatlekar, Seema; Addya, Sankar; Salunek, Moreh; Orr, Christopher R.; Surrey, Saul; McKenzie, Steven; Fields, Jeremy Z.; Boman, Bruce M

    2013-01-01

    Our goal was to identify a unique gene expression signature for human colonic stem cells (SCs). Accordingly, we determined the gene expression pattern for a known SC-enriched region—the crypt bottom. Colonic crypts and isolated crypt subsections (top, middle, and bottom) were purified from fresh, normal, human, surgical specimens. We then used an innovative strategy that used two-color microarrays (∼18,500 genes) to compare gene expression in the crypt bottom with expression in the other cryp...

  14. Radioprotective effects of miso (fermented soy bean paste) against radiation in B6C3F1 mice. Increased small intestinal crypt survival, crypt lengths and prolongation of average time to death

    International Nuclear Information System (INIS)

    The radioprotective effect of miso, a fermentation product from soy bean, was investigated with reference to the survival time, crypt survival and jejunum crypt length in male B6C3F1 mice. Miso at three different fermentation stages (early-, medium- and long-term fermented miso) was mixed in MF diet into biscuits at 10% and was administered from 1 week before irradiation. Animal survival in the long-term fermented miso group was significantly prolonged as compared with the short-term fermented miso and MF cases after 8 Gy of 60Co-γ-ray irradiation at a dose rate of 2 Gy min-1. Delay in mortality was evident in all three miso groups, with significantly increased survival. At doses of 10 and 12 Gy X-irradiation at a dose rate of 4 Gy min-1, the treatment with long-term fermented miso significantly increased crypt survival. Also the protective influence against irradiation in terms of crypt lengths in the long-term fermented miso group was significantly greater than in the short-term or medium-term fermented miso and MF diet groups. Thus, prolonged fermentation appears to be very important for protection against radiation effects. (author)

  15. Psychometric Characteristics of the Aberrant Behavior Checklist.

    Science.gov (United States)

    Aman, Michael G.; And Others

    1985-01-01

    Information is presented on the psychometric characteristics of the Aberrant Behavior Checklist, a measure of psychotropic drug effects. Internal consistency and test-retest reliability of the checklist appeared very good. Interrater reliability was generally in the moderate range. In general, validity was established for most Aberrant Behavior…

  16. Prebiotics prevent the appearance of aberrant crypt foci (ACF) in the colon of BALB/c mice for increasing the gene expression of p16 protein.

    Science.gov (United States)

    Gomides, Antônio Frederico Freitas; de Paula, Sérgio Oliveira; Gonçalves, Reggiani Vilela; de Oliveira, Leandro Licursi; Ferreira, Célia Lúcia de Luces Fortes; Comastri, Débora Silva; Peluzio, Maria do Carmo Gouveia

    2014-10-01

    Existen estudios que demuestran la eficacia de fibras para reducir la aparición de focos de cripta aberrantes (FCA) en roedores. Objetivo: El objetivo de este estudio consistió en investigar los efectos preventivos de los fructooligosacáridos (FOS) y el prebiótico inulina sobre la aparición de FCA en ratones. Materiales y métodos: Las técnicas empleadas fueron: RT-PCR para evaluar la expresión génica de p16, p21, p54, ciclina D1 y ciclina E en el colon distal; la cuantificación del Número de FCA y la medición de la actividad de la catalasa en el hígado y el colon distal. Los animales fueron divididos en cinco tratamientos (n=8); C-: dieta AIN93M sin fibra + DMH (1.2-dimetilhidrazina); INL: dieta AIN93M con inulina; INLCA: dieta AIN93M con inulina + DMH; FOS: dieta ANIN93M con FOS; FOSCA: dieta AIN93M con FOS + DMH, durante 15 semanas. Resultados: La inulina previno la aparición de FCA en el colon proximal, medio y distal, comparado con el control sin fibras. En el colon medio y distal, FOS también fue efectiva para prevenir la incidencia de FCA. Esta efectividad podría ser atribuida al aumento de la expresión génica de p16 tras el tratamiento con FOS. Ambos prebióticos también disminuyeron la actividad de la catalasa en el colon distal, lo que sugiere un efecto antioxidante. Conclusión: Estos resultados sugieren un efecto antioxidante de los prebióticos que podría atribuirse a un aumento de la expresión génica de p16.

  17. Different effects of short- and long-chained fructans on large intestinal physiology and carcinogen-induced aberrant crypt foci in rats

    DEFF Research Database (Denmark)

    Poulsen, Morten; Molck, Anne-Marie; Jacobsen, Bodil Lund

    2002-01-01

    Inulin-type fructans, which are nondigestible carbohydrates, have been shown to modulate the number of induced preneoplastic lesions in the colon as well as the colonic microflora in laboratory animals. The present study was designed to investigate the effect of a short- and long-chained inulin...

  18. Effect of diets fortified with tomatoes or onions with variable quercetin-glycoside content on azoxymethane-induced aberrant crypt foci in the colon of rats

    NARCIS (Netherlands)

    Femia, A.P.; Caderni, G.; Ianni, M.; Salvadori, M.; Schijlen, E.G.W.M.; Collins, G.; Bovy, A.G.; Dolara, P.

    2003-01-01

    Background: Onion and tomato are vegetables widely consumed by humans and epidemiological studies show an inverse association between vegetable consumption and colon cancer risk; however, the effect on colon cancer of diets containing high levels of vegetables like onion and tomato are not clear. Ai

  19. Probiotics Lactobacillus rhamnosus GG, Lactobacillus acidophilus suppresses DMH-induced procarcinogenic fecal enzymes and preneoplastic aberrant crypt foci in early colon carcinogenesis in Sprague Dawley rats.

    Science.gov (United States)

    Verma, Angela; Shukla, Geeta

    2013-01-01

    Diet makes an important contribution to colorectal cancer (CRC) risk implying risks for CRC are potentially reducible. Therefore, the probiotics have been suggested as the prophylactic measure in colon cancer. In this study, different probiotics were used to compare their protective potential against 1,2 dimethylhydrazine dihydrochloride (DMH)-induced chemical colon carcinogenesis in Sprague Dawley rats. Animals belonging to different probiotic groups were fed orally with 1 × 10(9) lactobacilli daily for 1 week, and then a weekly injection of DMH was given intraperitoneally for 6 wks with daily administration of probiotic. Lactobacillus GG and L.acidophilus + DMH-treated animals had maximum percent reduction in ACF counts. A significant decrease (P colon morphology of animals belonging to various probiotic + DMH-treated rats compared with DMH-treated alone. The results indicated that probiotics, L.GG, and L.acidophilus can be used as the better prophylactic agents for experimental colon carcinogenesis. PMID:23368917

  20. Aberration compensation in charged particle projection lithography

    International Nuclear Information System (INIS)

    Projection systems offer the opportunity to increase the throughput for charged particle lithography, because such systems image a large area of a mask directly on to a wafer as a single shot. Shots have to be imaged over a certain range of off-axis distances at the wafer to increase the writing speed, because shot sizes are limited to about 0.25x0.25 mm2 due to aberrations. In a projection system with only lenses, however, the aberrations for off-axis shots are still very large, and some aberration compensation elements need to be introduced. In this paper, three aberration compensation elements (deflectors, stigmators and dynamic focus lenses) are first discussed, a suite of newly developed software, called PROJECTION, based on this principle and our unified aberration theory is then described, and an illustrative example computed with the software is finally given

  1. Measurement of the cell membrane capacitance and conductance of colonic crypt cells of the rat using the patch clamp technique

    OpenAIRE

    Schill, C.

    2005-01-01

    Using the patch clamp technique the membrane capacitance and membrane conductance of colonic crypt cells of the rat was measured. The influence of the intracellular agonists Ca++, cAMP and of osmotic changes on the membrane capacitance and conductance was studied.

  2. Molecular mapping to species level of the tonsillar crypt microbiota associated with health and recurrent tonsillitis

    DEFF Research Database (Denmark)

    Jensen, Anders; Fagö-Olsen, Helena; Sørensen, Christian Hjort;

    2013-01-01

    level. A complex microbiota consisting of between 42 and 110 taxa was demonstrated in both children and adults. This included a core microbiome of 12 abundant genera found in all samples regardless of age and health status. Yet, Haemophilus influenzae, Neisseria species, and Streptococcus pneumoniae...... and included species that are considered putative pathogens in periodontal diseases, i.e. Porphyromonas gingivalis, Porphyromonas endodontalis, and Tannerella forsythia. Unifrac analysis showed that recurrent tonsillitis is associated with a shift in the microbiota of the tonsillar crypts. Fusobacterium...... is a polymicrobial infection in which interactions within consortia of taxa play an etiologic role. The study contributes to the human microbiome data, to the understanding of the etiology of infections affecting the tonsils, and forms a basis for further insight into the consequences of the intense microbe...

  3. La crypte de la cathédrale Saint-Étienne d’Auxerre (Yonne

    Directory of Open Access Journals (Sweden)

    Christian Sapin

    2010-10-01

    Full Text Available Amorce de l’aboutissement du vaste programme d’étude de la crypte de la cathédrale Saint-Étienne d’Auxerre entreprise depuis plusieurs années, la campagne archéologique, qui s’est déroulée exceptionnellement au cours du mois de janvier 2009, s’est limitée aux deux tiers de l’espace fouille de la chapelle d’axe. En effet, cette campagne a très vite rencontré les importantes excavations du milieu du xixe siècle avec une grande hauteur de remblais (1,50 m. C’est lors de ces travaux, accomplis s...

  4. Interactions of radiation and 5-fluorouracil, cyclophosphamide or methotrexate in intestinal crypt cells

    International Nuclear Information System (INIS)

    The interactions of radiation and 5-fluorouracil (5-FU), cyclophosphamide (CTX), or methotrexate (MTX) in mouse jejunal crypt cells were studied using the microcolony survival assay. 5-FU given from 48 hr before to 24 hr after irradiation resulted in an almost constant, increased cell kill except at injection 6 hr after irradiation, which resulted in a more pronounced effect. CTX enhanced the radiation effect only when given simultaneously with or up to 3 hr after irradiation. The effect of MTX, extremely dependent on the sequence and interval between drug administration and irradiation, was most prominent when administered 1 hr before irradiation. At this drug-radiation interval, the D0 surprisingly increased by a factor of 2.4, whereas MTX 15 min before irradiation displaced the survival curve to the left without changing the D0. The influence of MTX on the radiation response disappeared when the drug was given either 96 hr before or 3 hr after irradiation

  5. Relative biological effects of carbon ion beams on mouse intestinal crypts

    Energy Technology Data Exchange (ETDEWEB)

    Basaki, Kiyoshi; Abe, Yoshinao [Hirosaki Univ., Aomori (Japan). School of Medicine; Tatsuzaki, Hideo; Akaizawa, Takashi; Ando, Soichiro; Ando, Koichi

    1998-03-01

    The relative biological effect (RBE) of carbon ion beams on mouse intestinal crypt cells were studied. Survival fractions of apoptotic sensitive cells, mitotic delay and colony assay were used for endpoints. Female C3H mice were total body irradiated using a carbon ion beam (290 MeV/u, 6 cm SOBP) at the National Institute of Radiological Science. For counting apoptosis and mitosis, the animals were irradiated either at LET of 70 keV/mm or 40 keV/mm. Fifteen minutes after irradiation, the mice received vincristine sulfate (0.8 mg/kg) and were sacrificed 2 hours and 45 minutes later. For colony assay, the animals were irradiated at an LET of 70 keV/mm and were sacrificed 3.5 days later. Jejunum were excised, fixed and cut into slices. The slides were stained with Hematoxylin and Eosin. Apoptosis-pyknotic cell- and mitosis were counted and survival fractions of apoptotic sensitive cells and mitotic delay time were obtained. The number of colonies were counted and survival fractions per circumference were obtained. Using these endpoints, RBEs were obtained. For survival fractions of apoptotic sensitive cells, no LET difference was observed and RBE was 1.7. For mitotic delay time, RBE was 2.3 and 1.7 at an LET of 70 keV/mm and 40 keV/mm, respectively. For colony assay, the RBE was 2.0-2.1. The different RBEs from three endpoints of the jejunal crypt may reflect each nature of the radiosensitivity to the carbon ion beam. In summary that mitotic delay time exhibited the same RBE as colony assay and RBE regarding apoptosis was less than those RBEs. (author)

  6. The specialised structure of crypt epithelium in the human palatine tonsil and its functional significance.

    Science.gov (United States)

    Perry, M E

    1994-08-01

    Material from 25 human palatine tonsils was studied by light microscopy, immunocytochemistry, scanning and transmission electron microscopy. Special attention was focused on the structure of the epithelium lining the tonsillar crypts in the context of its ascribed immunological functions. This epithelium was not uniform and contained patches of stratified squamous nonkeratinising epithelium and patches of reticulated sponge-like epithelium. The degree of reticulation of the epithelial cells and the infiltration of nonepithelial cells varied. Reticulated patches were associated with disruptions in the continuity of basement membrane, and often also with desquamation of the upper cell layers, and contained numerous small blood vessels. The epithelial cells showed considerable variation in their morphology when surrounded by infiltrating cells. The rearrangement of their cytoskeleton and redistribution of desmosomal contacts indicate the responsiveness and dynamic nature of such epithelium. Cytoplasmic glycogen granules, located in the upper strata, suggest the possibility of energy-demanding functions such as absorption and secretion. The numerous membrane-coating granules may have contributed to cell membrane thickening and possibly also to tonsillar mucosal protection. Some areas contained a few keratohyalin granules but there was little evidence of keratinisation. The presence, and sometimes the predominance, of nonepithelial cells was characteristic of the reticulated epithelium. T and B cells often infiltrated the whole epithelial thickness, and many plasma cells were located around intraepithelial vessels, while macrophages and interdigitating cells showed a patchy distribution. It is proposed that the major functions of the reticulated epithelium are: (1) to provide a favourable environment for the intimate contact between the effector cells of immune responses; (2) to facilitate direct transport of antigens; (3) to synthesise the secretory component

  7. Molecular mapping to species level of the tonsillar crypt microbiota associated with health and recurrent tonsillitis.

    Directory of Open Access Journals (Sweden)

    Anders Jensen

    Full Text Available The human palatine tonsils, which belong to the central antigen handling sites of the mucosal immune system, are frequently affected by acute and recurrent infections. This study compared the microbiota of the tonsillar crypts in children and adults affected by recurrent tonsillitis with that of healthy adults and children with tonsillar hyperplasia. An in-depth 16S rRNA gene based pyrosequencing approach combined with a novel strategy that included phylogenetic analysis and detection of species-specific sequence signatures enabled identification of the major part of the microbiota to species level. A complex microbiota consisting of between 42 and 110 taxa was demonstrated in both children and adults. This included a core microbiome of 12 abundant genera found in all samples regardless of age and health status. Yet, Haemophilus influenzae, Neisseria species, and Streptococcus pneumoniae were almost exclusively detected in children. In contrast, Streptococcus pseudopneumoniae was present in all samples. Obligate anaerobes like Porphyromonas, Prevotella, and Fusobacterium were abundantly present in children, but the species diversity of Porphyromonas and Prevotella was larger in adults and included species that are considered putative pathogens in periodontal diseases, i.e. Porphyromonas gingivalis, Porphyromonas endodontalis, and Tannerella forsythia. Unifrac analysis showed that recurrent tonsillitis is associated with a shift in the microbiota of the tonsillar crypts. Fusobacterium necrophorum, Streptococcus intermedius and Prevotella melaninogenica/histicola were associated with recurrent tonsillitis in adults, whereas species traditionally associated with acute tonsillitis like pyogenic streptococci and Staphylococcus aureus were scarce. The findings suggest that recurrent tonsillitis is a polymicrobial infection in which interactions within consortia of taxa play an etiologic role. The study contributes to the human microbiome data, to the

  8. Bacterial colonization of colonic crypt mucous gel and disease activity in ulcerative colitis.

    LENUS (Irish Health Repository)

    Rowan, Fiachra

    2012-02-01

    OBJECTIVE: To optimize total bacterial 16S rRNA quantification in microdissected colonic crypts in healthy controls and patients with ulcerative colitis (UC) and to characterize the findings with disease activity. BACKGROUND: Microscopic and molecular techniques have recently converged to allow bacterial enumeration in remote anatomic locations [eg, crypt-associated mucous gel (CAMG)]. The aims of this study were to combine laser capture microdissection (LCM) and 16S rRNA-based quantitative polymerase chain reaction (qPCR) to determine total bacterial copy number in CAMG both in health and in UC and to characterize the findings with disease activity. METHODS: LCM was used to microdissect CAMG from colonic mucosal biopsies from controls (n = 20) and patients with acute (n = 10) or subacute (n = 10) UC. Pan-bacterial 16S rRNA copy number per millimeter square in samples from 6 locations across the large bowel was obtained by qPCR using Desulfovibrio desulfuricans as a reference strain. Copy numbers were correlated with the UC disease activity index (UCDAI) and the simple clinical colitis activity index (SCCAI). RESULTS: Bacterial colonization of CAMG was detectable in all groups. Copy numbers were significantly reduced in acute UC. In subacute colitis, there was a positive correlation between copy number and UCDAI and SCCAI in the ascending, transverse and sigmoid colon. CONCLUSIONS: This study describes a sensitive method of quantitatively assessing bacterial colonization of the colonic CAMG. A positive correlation was found between CAMG bacterial load and subacute disease activity in UC, whereas detectable bacterial load was reduced in acute UC.

  9. Biological intercomparison using gut crypt survivals for proton and carbon-ion beams

    International Nuclear Information System (INIS)

    Charged particle therapy depends on biological information for the dose prescription. Relative biological effectiveness or RBE for this requirement could basically be provided by experimental data. As RBE values of protons and carbon ions depend on several factors such as cell/tissue type, biological endpoint, dose and fractionation schedule, a single RBE value could not deal with all different radiosensitivities. However, any biological model with accurate reproducibility is useful for comparing biological effectiveness between different facilities. We used mouse gut crypt survivals as endpoint, and compared the cell killing efficiency of proton beams at three Japanese facilities. Three Linac X-ray machines with 4 and 6 MeV were used as reference beams, and there was only a small variation (coefficient of variance<2%) in biological effectiveness among them. The RBE values of protons relative to Linac X-rays ranged from 1.0 to 1.11 at the middle of a 6-cm SOBP (spread-out Bragg peak) and from 0.96 to 1.01 at the entrance plateau. The coefficient of variance for protons ranged between 4.0 and 5.1%. The biological comparison of carbon ions showed fairly good agreement in that the difference in biological effectiveness between National Institute of Radiological Sciences (NIRS)/ Heavy Ion Medical Accelerator in Chiba (HIMAC) and Gesellschaft fur Schwerionenforschung (GSI)/Heavy Ion Synchrotron (SIS) was 1% for three positions within the 6-cm SOBP. The coefficient of variance was <1.7, <0.6 and <1.6% for proximal, middle and distal SOBP, respectively. We conclude that the inter-institutional variation of biological effectiveness is smaller for carbon ions than protons, and that beam-spreading methods of carbon ions do not critically influence gut crypt survival. (author)

  10. Chromosome aberration assays in Allium

    Energy Technology Data Exchange (ETDEWEB)

    Grant, W.F.

    1982-01-01

    The common onion (Allium cepa) is an excellent plant for the assay of chromosome aberrations after chemical treatment. Other species of Allium (A. cepa var. proliferum, A. carinatum, A. fistulosum and A. sativum) have also been used but to a much lesser extent. Protocols have been given for using root tips from either bulbs or seeds of Allium cepa to study the cytological end-points, such as chromosome breaks and exchanges, which follow the testing of chemicals in somatic cells. It is considered that both mitotic and meiotic end-points should be used to a greater extent in assaying the cytogenetic effects of a chemical. From a literature survey, 148 chemicals are tabulated that have been assayed in 164 Allium tests for their clastogenic effect. Of the 164 assays which have been carried out, 75 are reported as giving a positive reaction, 49 positive and with a dose response, 1 positive and temperature-related, 9 borderline positive, and 30 negative; 76% of the chemicals gave a definite positive response. It is proposed that the Allium test be included among those tests routinely used for assessing chromosomal damage induced by chemicals.

  11. A two-dimensional model of the colonic crypt accounting for the role of the basement membrane and pericryptal fibroblast sheath.

    Directory of Open Access Journals (Sweden)

    Sara-Jane Dunn

    Full Text Available The role of the basement membrane is vital in maintaining the integrity and structure of an epithelial layer, acting as both a mechanical support and forming the physical interface between epithelial cells and the surrounding connective tissue. The function of this membrane is explored here in the context of the epithelial monolayer that lines the colonic crypt, test-tube shaped invaginations that punctuate the lining of the intestine and coordinate a regular turnover of cells to replenish the epithelial layer every few days. To investigate the consequence of genetic mutations that perturb the system dynamics and can lead to colorectal cancer, it must be possible to track the emerging tissue level changes that arise in the crypt. To that end, a theoretical crypt model with a realistic, deformable geometry is required. A new discrete crypt model is presented, which focuses on the interaction between cell- and tissue-level behaviour, while incorporating key subcellular components. The model contains a novel description of the role of the surrounding tissue and musculature, based upon experimental observations of the tissue structure of the crypt, which are also reported. A two-dimensional (2D cross-sectional geometry is considered, and the shape of the crypt is allowed to evolve and deform. Simulation results reveal how the shape of the crypt may contribute mechanically to the asymmetric division events typically associated with the stem cells at the base. The model predicts that epithelial cell migration may arise due to feedback between cell loss at the crypt collar and density-dependent cell division, an hypothesis which can be investigated in a wet lab. This work forms the basis for investigation of the deformation of the crypt structure that can occur due to proliferation of cells exhibiting mutant phenotypes, experiments that would not be possible in vivo or in vitro.

  12. Flow cytometric detection of aberrant chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Gray, J.W.; Lucas, J.; Yu, L.C.; Langlois, R.

    1983-05-11

    This report describes the quantification of chromosomal aberrations by flow cytometry. Both homogeneously and heterogeneously occurring chromosome aberrations were studied. Homogeneously occurring aberrations were noted in chromosomes isolated from human colon carcinoma (LoVo) cells, stained with Hoechst 33258 and chromomycin A3 and analyzed using dual beam flow cytometry. The resulting bivariate flow karyotype showed a homogeneously occurring marker chromosome of intermediate size. Heterogeneously occurring aberrations were quantified by slit-scan flow cytometry in chromosomes isolated from control and irradiated Chinese hamster cells and stained with propidium iodide. Heterogeneously occurring dicentric chromosomes were detected by their shapes (two centrometers). The frequencies of such chromosomes estimated by slit-scan flow cytometry correlated well with the frequencies determined by visual microscopy.

  13. Aberration features in directional dark matter detection

    CERN Document Server

    Bozorgnia, Nassim; Gondolo, Paolo

    2012-01-01

    The motion of the Earth around the Sun causes an annual change in the magnitude and direction of the arrival velocity of dark matter particles on Earth, in a way analogous to aberration of stellar light. In directional detectors, aberration of weakly interacting massive particles (WIMPs) modulates the pattern of nuclear recoil directions in a way that depends on the orbital velocity of the Earth and the local galactic distribution of WIMP velocities. Knowing the former, WIMP aberration can give information on the latter, besides being a curious way of confirming the revolution of the Earth and the extraterrestrial provenance of WIMPs. While observing the full aberration pattern requires extremely large exposures, we claim that the annual variation of the mean recoil direction or of the event counts over specific solid angles may be detectable with moderately large exposures. For example, integrated counts over galactic hemispheres separated by planes perpendicular to Earth's orbit would modulate annually, res...

  14. Catadioptric aberration correction in cathode lens microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tromp, R.M. [IBM T.J. Watson Research Center, PO Box 218, Yorktown Heights, NY 10598 (United States); Kamerlingh Onnes Laboratory, Leiden Institute of Physics, Niels Bohrweg 2, 2333 CA Leiden (Netherlands)

    2015-04-15

    In this paper I briefly review the use of electrostatic electron mirrors to correct the aberrations of the cathode lens objective lens in low energy electron microscope (LEEM) and photo electron emission microscope (PEEM) instruments. These catadioptric systems, combining electrostatic lens elements with a reflecting mirror, offer a compact solution, allowing simultaneous and independent correction of both spherical and chromatic aberrations. A comparison with catadioptric systems in light optics informs our understanding of the working principles behind aberration correction with electron mirrors, and may point the way to further improvements in the latter. With additional developments in detector technology, 1 nm spatial resolution in LEEM appears to be within reach. - Highlights: • The use of electron mirrors for aberration correction in LEEM/PEEM is reviewed. • A comparison is made with similar systems in light optics. • Conditions for 1 nm spatial resolution are discussed.

  15. Catadioptric aberration correction in cathode lens microscopy

    International Nuclear Information System (INIS)

    In this paper I briefly review the use of electrostatic electron mirrors to correct the aberrations of the cathode lens objective lens in low energy electron microscope (LEEM) and photo electron emission microscope (PEEM) instruments. These catadioptric systems, combining electrostatic lens elements with a reflecting mirror, offer a compact solution, allowing simultaneous and independent correction of both spherical and chromatic aberrations. A comparison with catadioptric systems in light optics informs our understanding of the working principles behind aberration correction with electron mirrors, and may point the way to further improvements in the latter. With additional developments in detector technology, 1 nm spatial resolution in LEEM appears to be within reach. - Highlights: • The use of electron mirrors for aberration correction in LEEM/PEEM is reviewed. • A comparison is made with similar systems in light optics. • Conditions for 1 nm spatial resolution are discussed

  16. Dynamics of the eye's wave aberration.

    Science.gov (United States)

    Hofer, H; Artal, P; Singer, B; Aragón, J L; Williams, D R

    2001-03-01

    It is well known that the eye's optics exhibit temporal instability in the form of microfluctuations in focus; however, almost nothing is known of the temporal properties of the eye's other aberrations. We constructed a real-time Hartmann-Shack (HS) wave-front sensor to measure these dynamics at frequencies as high as 60 Hz. To reduce spatial inhomogeneities in the short-exposure HS images, we used a low-coherence source and a scanning system. HS images were collected on three normal subjects with natural and paralyzed accommodation. Average temporal power spectra were computed for the wave-front rms, the Seidel aberrations, and each of 32 Zernike coefficients. The results indicate the presence of fluctuations in all of the eye's aberration, not just defocus. Fluctuations in higher-order aberrations share similar spectra and bandwidths both within and between subjects, dropping at a rate of approximately 4 dB per octave in temporal frequency. The spectrum shape for higher-order aberrations is generally different from that for microfluctuations of accommodation. The origin of these measured fluctuations is not known, and both corneal/lenticular and retinal causes are considered. Under the assumption that they are purely corneal or lenticular, calculations suggest that a perfect adaptive optics system with a closed-loop bandwidth of 1-2 Hz could correct these aberrations well enough to achieve diffraction-limited imaging over a dilated pupil. PMID:11265680

  17. Ground-penetrating radar investigation of St. Leonard's Crypt under the Wawel Cathedral (Cracow, Poland) - COST Action TU1208

    Science.gov (United States)

    Benedetto, Andrea; Pajewski, Lara; Dimitriadis, Klisthenis; Avlonitou, Pepi; Konstantakis, Yannis; Musiela, Małgorzata; Mitka, Bartosz; Lambot, Sébastien; Żakowska, Lidia

    2016-04-01

    The Wawel ensemble, including the Royal Castle, the Wawel Cathedral and other monuments, is perched on top of the Wawel hill immediately south of the Cracow Old Town, and is by far the most important collection of buildings in Poland. St. Leonard's Crypt is located under the Wawel Cathedral of St Stanislaus BM and St Wenceslaus M. It was built in the years 1090-1117 and was the western crypt of the pre-existing Romanesque Wawel Cathedral, so-called Hermanowska. Pope John Paul II said his first Mass on the altar of St. Leonard's Crypt on November 2, 1946, one day after his priestly ordination. The interior of the crypt is divided by eight columns into three naves with vaulted ceiling and ended with one apse. The tomb of Bishop Maurus, who died in 1118, is in the middle of the crypt under the floor; an inscription "+ MAVRVS EPC MCXVIII +" indicates the burial place and was made in 1938 after the completion of archaeological works which resulted in the discovery of this tomb. Moreover, the crypt hosts the tombs of six Polish kings and heroes: Michał Korybut Wiśniowiecki (King of the Polish-Lithuanian Commonwealth), Jan III Sobieski (King of the Polish-Lithuanian Commonwealth and Commander at the Battle of Vienna), Maria Kazimiera (Queen of the Polish-Lithuanian Commonwealth and consort to Jan III Sobieski), Józef Poniatowski (Prince of Poland and Marshal of France), Tadeusz Kościuszko (Polish general, revolutionary and a Brigadier General in the American Revolutionary War) and Władysław Sikorski (Prime Minister of the Polish Government in Exile and Commander-in-Chief of the Polish Armed Forces). The adjacent six crypts and corridors host the tombs of the other Polish kings, from Sigismund the Old to Augustus II the Strong, their families and several Polish heroes. In May 2015, the COST (European COoperation in Science and Technology) Action TU1208 "Civil engineering applications of Ground Penetrating Radar" organised and offered a Training School (TS) on the

  18. Pulse compressor with aberration correction

    Energy Technology Data Exchange (ETDEWEB)

    Mankos, Marian [Electron Optica, Inc., Palo Alto, CA (United States)

    2015-11-30

    In this SBIR project, Electron Optica, Inc. (EOI) is developing an electron mirror-based pulse compressor attachment to new and retrofitted dynamic transmission electron microscopes (DTEMs) and ultrafast electron diffraction (UED) cameras for improving the temporal resolution of these instruments from the characteristic range of a few picoseconds to a few nanoseconds and beyond, into the sub-100 femtosecond range. The improvement will enable electron microscopes and diffraction cameras to better resolve the dynamics of reactions in the areas of solid state physics, chemistry, and biology. EOI’s pulse compressor technology utilizes the combination of electron mirror optics and a magnetic beam separator to compress the electron pulse. The design exploits the symmetry inherent in reversing the electron trajectory in the mirror in order to compress the temporally broadened beam. This system also simultaneously corrects the chromatic and spherical aberration of the objective lens for improved spatial resolution. This correction will be found valuable as the source size is reduced with laser-triggered point source emitters. With such emitters, it might be possible to significantly reduce the illuminated area and carry out ultrafast diffraction experiments from small regions of the sample, e.g. from individual grains or nanoparticles. During phase I, EOI drafted a set of candidate pulse compressor architectures and evaluated the trade-offs between temporal resolution and electron bunch size to achieve the optimum design for two particular applications with market potential: increasing the temporal and spatial resolution of UEDs, and increasing the temporal and spatial resolution of DTEMs. Specialized software packages that have been developed by MEBS, Ltd. were used to calculate the electron optical properties of the key pulse compressor components: namely, the magnetic prism, the electron mirror, and the electron lenses. In the final step, these results were folded

  19. Aberrant O-glycosylation and anti-glycan antibodies in an autoimmune disease IgA nephropathy and breast adenocarcinoma

    DEFF Research Database (Denmark)

    Stuchlová Horynová, Milada; Raška, Milan; Clausen, Henrik;

    2013-01-01

    -glycosylation, although different for MUC1 and IgA1, include dysregulation in glycosyltransferase expression, stability, and/or intracellular localization. Moreover, these aberrant glycoproteins are recognized by antibodies, although with different consequences. In breast cancer, elevated levels of antibodies recognizing......Glycosylation abnormalities have been observed in autoimmune diseases and cancer. Here, we compare mechanisms of aberrant O-glycosylation, i.e., formation of Tn and sialyl-Tn structures, on MUC1 in breast cancer, and on IgA1 in an autoimmune disease, IgA nephropathy. The pathways of aberrant O...... aberrant MUC1 are associated with better outcome, whereas in IgA nephropathy, the antibodies recognizing aberrant IgA1 are part of the pathogenetic process....

  20. β-Arrestin-2 modulates radiation-induced intestinal crypt progenitor/stem cell injury.

    Science.gov (United States)

    Liu, Z; Tian, H; Jiang, J; Yang, Y; Tan, S; Lin, X; Liu, H; Wu, B

    2016-09-01

    Intestinal crypt progenitor/stem (ICPS) cell apoptosis and vascular endothelial cell apoptosis are responsible for the initiation and development of ionizing radiation (IR)-evoked gastrointestinal syndrome. The signaling mechanisms underlying IR-induced ICPS cell apoptosis remain largely unclear. Our findings provide evidence that β-arrestin-2 (βarr2)-mediated ICPS cell apoptosis is crucial for IR-stimulated intestinal injury. βArr2-deficient mice exhibited decreased ICPS cell and intestinal Lgr5(+) (leucine-rich repeat-containing G-protein-coupled receptor 5-positive) stem cell apoptosis, promoted crypt proliferation and reproduction, and protracted survival following lethal doses of radiation. Radioprotection in the ICPS cells isolated from βarr2-deficient mice depended on prolonged nuclear factor-κB (NF-κB) activation via direct interaction of βarr2 with IκBα and subsequent inhibition of p53-upregulated modulator of apoptosis (PUMA)-mediated mitochondrial dysfunction. Unexpectedly, βarr2 deficiency had little effect on IR-induced intestinal vascular endothelial cell apoptosis in mice. Consistently, βarr2 knockdown also provided significant radioresistance by manipulating NF-κB/PUMA signaling in Lgr5(+) cells in vitro. Collectively, these observations show that targeting the βarr2/NF-κB/PUMA novel pathway is a potential radiomitigator for limiting the damaging effect of radiotherapy on the gastrointestinal system. Significance statement: acute injury to the intestinal mucosa is a major dose-limiting complication of abdominal radiotherapy. The issue of whether the critical factor for the initiation of radiation-induced intestinal injury is intestinal stem cell apoptosis or endothelial cell apoptosis remains unresolved. βArrs have recently been found to be multifunctional adaptor of apoptosis. Here, we found that β-arrestin-2 (βarr2) deficiency was associated with decreased radiation-induced ICPS cell apoptosis, which prolonged survival in

  1. Ground-penetrating radar investigation of St. Leonard's Crypt under the Wawel Cathedral (Cracow, Poland) - COST Action TU1208

    Science.gov (United States)

    Benedetto, Andrea; Pajewski, Lara; Dimitriadis, Klisthenis; Avlonitou, Pepi; Konstantakis, Yannis; Musiela, Małgorzata; Mitka, Bartosz; Lambot, Sébastien; Żakowska, Lidia

    2016-04-01

    The Wawel ensemble, including the Royal Castle, the Wawel Cathedral and other monuments, is perched on top of the Wawel hill immediately south of the Cracow Old Town, and is by far the most important collection of buildings in Poland. St. Leonard's Crypt is located under the Wawel Cathedral of St Stanislaus BM and St Wenceslaus M. It was built in the years 1090-1117 and was the western crypt of the pre-existing Romanesque Wawel Cathedral, so-called Hermanowska. Pope John Paul II said his first Mass on the altar of St. Leonard's Crypt on November 2, 1946, one day after his priestly ordination. The interior of the crypt is divided by eight columns into three naves with vaulted ceiling and ended with one apse. The tomb of Bishop Maurus, who died in 1118, is in the middle of the crypt under the floor; an inscription "+ MAVRVS EPC MCXVIII +" indicates the burial place and was made in 1938 after the completion of archaeological works which resulted in the discovery of this tomb. Moreover, the crypt hosts the tombs of six Polish kings and heroes: Michał Korybut Wiśniowiecki (King of the Polish-Lithuanian Commonwealth), Jan III Sobieski (King of the Polish-Lithuanian Commonwealth and Commander at the Battle of Vienna), Maria Kazimiera (Queen of the Polish-Lithuanian Commonwealth and consort to Jan III Sobieski), Józef Poniatowski (Prince of Poland and Marshal of France), Tadeusz Kościuszko (Polish general, revolutionary and a Brigadier General in the American Revolutionary War) and Władysław Sikorski (Prime Minister of the Polish Government in Exile and Commander-in-Chief of the Polish Armed Forces). The adjacent six crypts and corridors host the tombs of the other Polish kings, from Sigismund the Old to Augustus II the Strong, their families and several Polish heroes. In May 2015, the COST (European COoperation in Science and Technology) Action TU1208 "Civil engineering applications of Ground Penetrating Radar" organised and offered a Training School (TS) on the

  2. Duodenal crypt health following exposure to Cr(VI): Micronucleus scoring, γ-H2AX immunostaining, and synchrotron X-ray fluorescence microscopy.

    Science.gov (United States)

    Thompson, Chad M; Wolf, Jeffrey C; Elbekai, Reem H; Paranjpe, Madhav G; Seiter, Jennifer M; Chappell, Mark A; Tappero, Ryan V; Suh, Mina; Proctor, Deborah M; Bichteler, Anne; Haws, Laurie C; Harris, Mark A

    2015-08-01

    Lifetime exposure to high concentrations of hexavalent chromium [Cr(VI)] in drinking water results in intestinal damage and an increase in duodenal tumors in B6C3F1 mice. To assess whether these tumors could be the result of a direct mutagenic or genotoxic mode of action, we conducted a GLP-compliant 7-day drinking water study to assess crypt health along the entire length of the duodenum. Mice were exposed to water (vehicle control), 1.4, 21, or 180 ppm Cr(VI) via drinking water for 7 consecutive days. Crypt enterocytes in Swiss roll sections were scored as normal, mitotic, apoptotic, karyorrhectic, or as having micronuclei. A single oral gavage of 50mg/kg cyclophosphamide served as a positive control for micronucleus induction. Exposure to 21 and 180 ppm Cr(VI) significantly increased the number of crypt enterocytes. Micronuclei and γ-H2AX immunostaining were not elevated in the crypts of Cr(VI)-treated mice. In contrast, treatment with cyclophosphamide significantly increased numbers of crypt micronuclei and qualitatively increased γ-H2AX immunostaining. Synchrotron-based X-ray fluorescence (XRF) microscopy revealed the presence of strong Cr fluorescence in duodenal villi, but negligible Cr fluorescence in the crypt compartment. Together, these data indicate that Cr(VI) does not adversely effect the crypt compartment where intestinal stem cells reside, and provide additional evidence that the mode of action for Cr(VI)-induced intestinal cancer in B6C3F1 mice involves chronic villous wounding resulting in compensatory crypt enterocyte hyperplasia. PMID:26232259

  3. MicroRNA mir-16 is anti-proliferative in enterocytes and exhibits diurnal rhythmicity in intestinal crypts

    Energy Technology Data Exchange (ETDEWEB)

    Balakrishnan, Anita, E-mail: anita.balakrishnan@doctors.org.uk [Department of Surgery, Brigham and Women' s Hospital, Boston, MA 02115 (United States); Department of Surgery, Harvard Medical School, Boston, MA 02115 (United States); School of Clinical Sciences, Division of Gastroenterology, University of Liverpool, Liverpool L69 3GE (United Kingdom); Stearns, Adam T. [Department of Surgery, Brigham and Women' s Hospital, Boston, MA 02115 (United States); Department of Surgery, Harvard Medical School, Boston, MA 02115 (United States); Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 2JD (United Kingdom); Park, Peter J. [Department of Medicine, Brigham and Women' s Hospital, Boston, MA 02115 (United States); Harvard Medical School, Center for Biomedical Informatics, Boston, MA 02115 (United States); Dreyfuss, Jonathan M. [Department of Medicine, Brigham and Women' s Hospital, Boston, MA 02115 (United States); Ashley, Stanley W. [Department of Surgery, Brigham and Women' s Hospital, Boston, MA 02115 (United States); Department of Surgery, Harvard Medical School, Boston, MA 02115 (United States); Rhoads, David B. [Department of Surgery, Harvard Medical School, Boston, MA 02115 (United States); Pediatric Endocrine Unit, MassGeneral Hospital for Children, Boston, MA 02114 (United States); Tavakkolizadeh, Ali, E-mail: atavakkoli@partners.org [Department of Surgery, Brigham and Women' s Hospital, Boston, MA 02115 (United States); Department of Surgery, Harvard Medical School, Boston, MA 02115 (United States)

    2010-12-10

    Background and aims: The intestine exhibits profound diurnal rhythms in function and morphology, in part due to changes in enterocyte proliferation. The regulatory mechanisms behind these rhythms remain largely unknown. We hypothesized that microRNAs are involved in mediating these rhythms, and studied the role of microRNAs specifically in modulating intestinal proliferation. Methods: Diurnal rhythmicity of microRNAs in rat jejunum was analyzed by microarrays and validated by qPCR. Temporal expression of diurnally rhythmic mir-16 was further quantified in intestinal crypts, villi, and smooth muscle using laser capture microdissection and qPCR. Morphological changes in rat jejunum were assessed by histology and proliferation by immunostaining for bromodeoxyuridine. In IEC-6 cells stably overexpressing mir-16, proliferation was assessed by cell counting and MTS assay, cell cycle progression and apoptosis by flow cytometry, and cell cycle gene expression by qPCR and immunoblotting. Results: mir-16 peaked 6 hours after light onset (HALO 6) with diurnal changes restricted to crypts. Crypt depth and villus height peaked at HALO 13-14 in antiphase to mir-16. Overexpression of mir-16 in IEC-6 cells suppressed specific G1/S regulators (cyclins D1-3, cyclin E1 and cyclin-dependent kinase 6) and produced G1 arrest. Protein expression of these genes exhibited diurnal rhythmicity in rat jejunum, peaking between HALO 11 and 17 in antiphase to mir-16. Conclusions: This is the first report of circadian rhythmicity of specific microRNAs in rat jejunum. Our data provide a link between anti-proliferative mir-16 and the intestinal proliferation rhythm and point to mir-16 as an important regulator of proliferation in jejunal crypts. This function may be essential to match proliferation and absorptive capacity with nutrient availability.

  4. Mast cells in Canine parvovirus-2-associated enteritis with crypt abscess.

    Science.gov (United States)

    Woldemeskel, M W; Saliki, J T; Blas-Machado, U; Whittington, L

    2013-11-01

    The role of mast cells (MCs) in allergic reactions and parasitic infections is well established. Their involvement in host immune response against bacterial and viral infections is reported. In this study, investigation is made to determine if MCs are associated with Canine parvovirus-2 (CPV-2)-induced enteritis with crypt abscess (ECA). Mast cell count (MCC) was made on toluidine blue-stained intestinal sections from a total of 34 dogs. These included 16 dogs exhibiting ECA positive for CPV-2 and negative for Canine distemper virus and Canine coronavirus by immunohistochemistry and fluorescent antibody test, 12 dogs with inflammatory bowel disease (IBD), and 6 non-ECA/non-IBD (control) dogs. The average total MCC per high-power field in ECA (40.8 ± 2.2) and IBD (24.7 ± 2.1) was significantly higher (P .05), MCC was also higher in ECA than in IBD. The present study for the first time has documented significantly increased MCs in CPV-2-associated ECA as was previously reported for IBD, showing that MCs may also play an important role in CPV-2-associated ECA. Further studies involving more CPV-infected dogs are recommended to substantiate the findings.

  5. The correction of electron lens aberrations

    Energy Technology Data Exchange (ETDEWEB)

    Hawkes, P.W., E-mail: peter.hawkes@cemes.fr

    2015-09-15

    The progress of electron lens aberration correction from about 1990 onwards is chronicled. Reasonably complete lists of publications on this and related topics are appended. A present for Max Haider and Ondrej Krivanek in the year of their 65th birthdays. By a happy coincidence, this review was completed in the year that both Max Haider and Ondrej Krivanek reached the age of 65. It is a pleasure to dedicate it to the two leading actors in the saga of aberration corrector design and construction. They would both wish to associate their colleagues with such a tribute but it is the names of Haider and Krivanek (not forgetting Joachim Zach) that will remain in the annals of electron optics, next to that of Harald Rose. I am proud to know that both regard me as a friend as well as a colleague. - Highlights: • Geometrical aberration correction. • Chromatic aberration correction. • 50 pm resolution. • High-resolution electron energy-loss spectroscopy. • Extensive bibliographies.

  6. Optical advantages of astigmatic aberration corrected heliostats

    Science.gov (United States)

    van Rooyen, De Wet; Schöttl, Peter; Bern, Gregor; Heimsath, Anna; Nitz, Peter

    2016-05-01

    Astigmatic aberration corrected heliostats adapt their shape in dependence of the incidence angle of the sun on the heliostat. Simulations show that this optical correction leads to a higher concentration ratio at the target and thus in a decrease in required receiver aperture in particular for smaller heliostat fields.

  7. Prenatal hydronephrosis caused by aberrant renal vessels

    DEFF Research Database (Denmark)

    Lenz, K; Thorup, Jørgen Mogens; Rabol, A;

    1996-01-01

    With routine use of obstetric ultrasonography, fetal low-grade hydronephrosis is commonly detected, but may resolve spontaneously after birth. Two cases are presented to illustrate that in some cases such findings can express intermittent hydronephrosis caused by aberrant renal vessels. Renal...

  8. Anti-forensics of chromatic aberration

    Science.gov (United States)

    Mayer, Owen; Stamm, Matthew C.

    2015-03-01

    Over the past decade, a number of information forensic techniques have been developed to identify digital image manipulation and falsification. Recent research has shown, however, that an intelligent forger can use anti-forensic countermeasures to disguise their forgeries. In this paper, an anti-forensic technique is proposed to falsify the lateral chromatic aberration present in a digital image. Lateral chromatic aberration corresponds to the relative contraction or expansion between an image's color channels that occurs due to a lens's inability to focus all wavelengths of light on the same point. Previous work has used localized inconsistencies in an image's chromatic aberration to expose cut-and-paste image forgeries. The anti-forensic technique presented in this paper operates by estimating the expected lateral chromatic aberration at an image location, then removing deviations from this estimate caused by tampering or falsification. Experimental results are presented that demonstrate that our anti-forensic technique can be used to effectively disguise evidence of an image forgery.

  9. Adaptive and aberrant reward prediction signals in the human brain.

    NARCIS (Netherlands)

    Roiser, J.P.; Stephan, K.E.; Ouden, H.E.M. den; Friston, K.J.; Joyce, E.M.

    2010-01-01

    Theories of the positive symptoms of schizophrenia hypothesize a role for aberrant reinforcement signaling driven by dysregulated dopamine transmission. Recently, we provided evidence of aberrant reward learning in symptomatic, but not asymptomatic patients with schizophrenia, using a novel paradigm

  10. Genome-wide identification of significant aberrations in cancer genome

    Directory of Open Access Journals (Sweden)

    Yuan Xiguo

    2012-07-01

    Full Text Available Abstract Background Somatic Copy Number Alterations (CNAs in human genomes are present in almost all human cancers. Systematic efforts to characterize such structural variants must effectively distinguish significant consensus events from random background aberrations. Here we introduce Significant Aberration in Cancer (SAIC, a new method for characterizing and assessing the statistical significance of recurrent CNA units. Three main features of SAIC include: (1 exploiting the intrinsic correlation among consecutive probes to assign a score to each CNA unit instead of single probes; (2 performing permutations on CNA units that preserve correlations inherent in the copy number data; and (3 iteratively detecting Significant Copy Number Aberrations (SCAs and estimating an unbiased null distribution by applying an SCA-exclusive permutation scheme. Results We test and compare the performance of SAIC against four peer methods (GISTIC, STAC, KC-SMART, CMDS on a large number of simulation datasets. Experimental results show that SAIC outperforms peer methods in terms of larger area under the Receiver Operating Characteristics curve and increased detection power. We then apply SAIC to analyze structural genomic aberrations acquired in four real cancer genome-wide copy number data sets (ovarian cancer, metastatic prostate cancer, lung adenocarcinoma, glioblastoma. When compared with previously reported results, SAIC successfully identifies most SCAs known to be of biological significance and associated with oncogenes (e.g., KRAS, CCNE1, and MYC or tumor suppressor genes (e.g., CDKN2A/B. Furthermore, SAIC identifies a number of novel SCAs in these copy number data that encompass tumor related genes and may warrant further studies. Conclusions Supported by a well-grounded theoretical framework, SAIC has been developed and used to identify SCAs in various cancer copy number data sets, providing useful information to study the landscape of cancer genomes

  11. Inhibition of azoxymethane-induced DNA adduct formation by Aloe arborescens var. natalensis.

    Science.gov (United States)

    Shimpo, Kan; Chihara, Takeshi; Beppu, Hidehiko; Ida, Chikako; Kaneko, Takaaki; Hoshino, Motoyuki; Kuzuya, Hiroshi

    2003-01-01

    To clarify the possible mechanisms of inhibition of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in the rat colorectum by freeze-dried whole leaves of Aloe arborescens var. natalensis (Kidachi aloe) (hereinafter referred to as ALOE) and commercial crude aloin (Sigma A-0451; from Curacao aloe) (hereinafter ALOIN), we studied the effects of ALOE and ALOIN on the formation of AOM-induced DNA adducts (O6-methylguanine; O6-MeG) in rats. Male F344 rats (4 weeks old) were fed a basal diet, or experimental diets containing 5%ALOE or 0.25%ALOIN for 5 weeks. All rats were injected s.c. twice with 15 mg/kg AOM, once at the end of week 1, and once at the end of week 2. The animals were sacrificed 6 hours after the second injection to analyze DNA adducts (O6-MeG) in the colorectum. Dietary administration of ALOE significantly inhibited the O6-MeG levels (50% reduction) compared with controls, whereas the O6-MeG levels in the ALOIN-fed rats showed a tendency to decrease (by 30%), although not significantly. In this study, we also measured the enzyme activity and mRNA level of cytochrome (CYP) 2E1, known to be responsible for the activation of AOM, in rat liver. ALOE-fed rats showed significantly reduced CYP2E1 enzymatic activity (27% reduction) compared with controls. On the other hand, the activity in ALOIN-fed rats tended to decrease by 11%, although not significantly. The CYP2E1 mRNA levels in ALOE- and ALOIN-fed rats were slightly reduced (9.7% and 5.2%, respectively). These results may explain, at least in part, the previously observed inhibitory effects of ALOE and ALOIN, especially ALOE on AOM-induced ACF formation in the rat colorectum. PMID:14507246

  12. The correction of electron lens aberrations.

    Science.gov (United States)

    Hawkes, P W

    2015-09-01

    The progress of electron lens aberration correction from about 1990 onwards is chronicled. Reasonably complete lists of publications on this and related topics are appended. A present for Max Haider and Ondrej Krivanek in the year of their 65th birthdays. By a happy coincidence, this review was completed in the year that both Max Haider and Ondrej Krivanek reached the age of 65. It is a pleasure to dedicate it to the two leading actors in the saga of aberration corrector design and construction. They would both wish to associate their colleagues with such a tribute but it is the names of Haider and Krivanek (not forgetting Joachim Zach) that will remain in the annals of electron optics, next to that of Harald Rose. I am proud to know that both regard me as a friend as well as a colleague. PMID:26025209

  13. Excavation of the Crypt of the Leifeng Pagoda in Hangzhou%杭州雷峰塔地宫的清理

    Institute of Scientific and Technical Information of China (English)

    浙江省文物考古研究所

    2002-01-01

    In 2000~2001, the Zhejiang Provincial Institute of Cultural Relics and Archaeology carried out archaeological excavation on the site of the Leifeng Pagoda on the southern shore of the West Lake in Hangzhou. Great achievements were obtained from the excavation of the crypt, pagoda-foundations and peripheral remains, with important stele inscriptions brought to light and more than 70 treasures yielded from the crypt. The Leifeng Pagoda is a Buddhist building constructed by the royal family of the Wuyue State. Its excavation filled in the gap of Buddhist pagoda archaeology of the Five Dynasties and Ten Kingdoms period. The results provided valuable material for studying the Buddhist pagoda form, crypt structure and monastery layout in the Five Dynasties period, as well as the historical background, Buddhist culture and the technological level at the final stage of the Wuyue State.

  14. Assessing the construct validity of aberrant salience

    Directory of Open Access Journals (Sweden)

    Kristin Schmidt

    2009-12-01

    Full Text Available We sought to validate the psychometric properties of a recently developed paradigm that aims to measure salience attribution processes proposed to contribute to positive psychotic symptoms, the Salience Attribution Test (SAT. The “aberrant salience” measure from the SAT showed good face validity in previous results, with elevated scores both in high-schizotypy individuals, and in patients with schizophrenia suffering from delusions. Exploring the construct validity of salience attribution variables derived from the SAT is important, since other factors, including latent inhibition/learned irrelevance, attention, probabilistic reward learning, sensitivity to probability, general cognitive ability and working memory could influence these measures. Fifty healthy participants completed schizotypy scales, the SAT, a learned irrelevance task, and a number of other cognitive tasks tapping into potentially confounding processes. Behavioural measures of interest from each task were entered into a principal components analysis, which yielded a five-factor structure accounting for ~75% percent of the variance in behaviour. Implicit aberrant salience was found to load onto its own factor, which was associated with elevated “Introvertive Anhedonia” schizotypy, replicating our previous finding. Learned irrelevance loaded onto a separate factor, which also included implicit adaptive salience, but was not associated with schizotypy. Explicit adaptive and aberrant salience, along with a measure of probabilistic learning, loaded onto a further factor, though this also did not correlate with schizotypy. These results suggest that the measures of learned irrelevance and implicit adaptive salience might be based on similar underlying processes, which are dissociable both from implicit aberrant salience and explicit measures of salience.

  15. Cosmological parameter estimation: impact of CMB aberration

    CERN Document Server

    Catena, Riccardo

    2012-01-01

    The peculiar motion of an observer with respect to the CMB rest frame induces an apparent deflection of the observed CMB photons, i.e. aberration, and a shift in their frequency, i.e. Doppler effect. Both effects distort the temperature multipoles a_lm's via a mixing matrix at any l. The common lore when performing a CMB based cosmological parameter estimation is to consider that Doppler affects only the l=1 multipole, and neglect any other corrections. In this paper we reconsider the validity of this assumption, showing that it is actually not robust when sky cuts are included to model CMB foreground contaminations. Assuming a simple fiducial cosmological model with five parameters, we simulated CMB temperature maps of the sky in a WMAP-like and in a Planck-like experiment and added aberration and Doppler effects to the maps. We then analyzed with a MCMC in a Bayesian framework the maps with and without aberration and Doppler effects in order to assess the ability of reconstructing the parameters of the fidu...

  16. Direct Measurements of Human Colon Crypt Stem Cell Niche Genetic Fidelity: The Role of Chance in Non-Darwinian Mutation Selection

    Directory of Open Access Journals (Sweden)

    Haeyoun eKang

    2013-10-01

    Full Text Available Perfect human stem cell genetic fidelity would prevent aging and cancer. However, perfection would be difficult to achieve, and aging is universal and cancers common. A hypothesis is that because mutations are inevitable over a human lifetime, downstream mechanisms have evolved to manage the deleterious effects of beneficial and lethal mutations. In the colon, a crypt stem cell architecture reduces the number of mitotic cells at risk for mutation accumulation, and multiple niche stem cells ensure that a lethal mutation within any single stem cell does not lead to crypt death. In addition, the architecture of the colon crypt stem cell niche may harness probability or chance to randomly discard many beneficial mutations that might lead to cancer. An analysis of somatic chromosome copy number alterations (CNAs reveals a lack of perfect fidelity in individual normal human crypts, with age-related increases and higher frequencies in ulcerative colitis, a proliferative, inflammatory disease. The age-related increase in somatic CNAs appears consistent with relatively normal replication error and cell division rates. Surprisingly, and similar to point mutations in cancer genomes, the types of crypt mutations were more consistent with random fixation rather than selection. In theory, a simple non-Darwinian way to nullify selection is to reduce the size of the reproducing population. Fates are more determined by chance rather than selection in very small populations, and therefore selection may be minimized within small crypt niches. The desired effect is that many beneficial mutations that might lead to cancer are randomly lost by drift rather than fixed by selection. The subdivision of the colon into multiple very small stem cell niches may trade Darwinian evolution for non-Darwinian somatic cell evolution, capitulating to aging but reducing cancer risks.

  17. Tonsillar crypt epithelium is an important extra-central nervous system site for viral replication in EV71 encephalomyelitis.

    Science.gov (United States)

    He, Yaoxin; Ong, Kien Chai; Gao, Zifen; Zhao, Xishun; Anderson, Virginia M; McNutt, Michael A; Wong, Kum Thong; Lu, Min

    2014-03-01

    Enterovirus 71 (EV71; family Picornaviridae, species human Enterovirus A) usually causes hand, foot, and mouth disease, which may rarely be complicated by fatal encephalomyelitis. We investigated extra-central nervous system (extra-CNS) tissues capable of supporting EV71 infection and replication, and have correlated tissue infection with expression of putative viral entry receptors, scavenger receptor B2 (SCARB2), and P-selectin glycoprotein ligand-1 (PSGL-1). Formalin-fixed, paraffin-embedded CNS and extra-CNS tissues from seven autopsy cases were examined by IHC and in situ hybridization to evaluate viral antigens and RNA. Viral receptors were identified with IHC. In all seven cases, the CNS showed stereotypical distribution of inflammation and neuronal localization of viral antigens and RNA, confirming the clinical diagnosis of EV71 encephalomyelitis. In six cases in which tonsillar tissues were available, viral antigens and/or RNA were localized to squamous epithelium lining the tonsillar crypts. Tissues from the gastrointestinal tract, pancreas, mesenteric nodes, spleen, and skin were all negative for viral antigens/RNA. Our novel findings strongly suggest that tonsillar crypt squamous epithelium supports active viral replication and represents an important source of viral shedding that facilitates person-to-person transmission by both the fecal-oral or oral-oral routes. It may also be a portal for viral entry. A correlation between viral infection and SCARB2 expression appears to be more significant than for PSGL-1 expression.

  18. Onset of transcription of the aminopeptidase N (leukemia antigen CD 13) gene at the crypt/villus transition zone during rabbit enterocyte differentiation

    DEFF Research Database (Denmark)

    Norén, O; Dabelsteen, E; Høyer, P E;

    1989-01-01

    The sequence of a cDNA clone (2.82 kbp) of rabbit intestinal aminopeptidase N (CD 13) is reported. Using the corresponding anti-sense RNA probe, the distribution of aminopeptidase N mRNA along the crypt/villus axis of the rabbit small intestine was studied by in situ hybridization. The aminopepti......The sequence of a cDNA clone (2.82 kbp) of rabbit intestinal aminopeptidase N (CD 13) is reported. Using the corresponding anti-sense RNA probe, the distribution of aminopeptidase N mRNA along the crypt/villus axis of the rabbit small intestine was studied by in situ hybridization...

  19. Radiotherapeutical chromosomal aberrations in laryngeal cancer patients

    Directory of Open Access Journals (Sweden)

    Stošić-Divjak Svetlana L.

    2009-01-01

    Full Text Available Introduction. The authors present the results of cytogenetic analysis of 21 patients with laryngeal carcinomas diagnosed and treated in the period 1995-2000 at the Institute of Otorhinolaryngology and Maxillofacial Surgery, Clinical Center of Serbia and Clinical Center of Novi Sad. Material and methods. The patients were specially monitored and the material was analyzed at the Institute of Human Genetics of the School of Medicine in Belgrade as well as in the Laboratory for Radiological Protection of the Institute of Occupational and Radiological Health 'Dr Dragomir Karajovic' in Belgrade. Results. The incidence of chromosomal aberrations and incidence of exchange of material between sister chromatids were observed in the preparation of the metaphasic lymphocyte chromosomes of the peripheral blood obtained in the culture. Structural aberrations were found on the chromosomes in the form of breakups, rings, translocations and dicentrics as early as after a single exposure of patients to tumor radiation dose of 2 Gy in the field sized 5x7. Out of the total number of 35 cultivated blood samples obtained from 13 patients, 21 were successfully cultivated and they were proved to contain chromosomal aberrations. Some of the peripheral blood samples failed to show cell growth in vitro due to the lethal cell damages in vivo. Discussion.. We have consluded that the number of structural aberrations cannot be used as a biological measure of the absorbed ionizing radiation dose. The presence of aberrations per se is indicative of the mutagenic effect of the ionizing radiation, which was also confirmed in our series on the original model by cultivation of the peripheral blood lymphocytes in the culture of the cells of the volunteer donors upon in vitro radiation. Using the method of bromdeoxyuridylreductase, the increased incidence of SCE as a mutagenic effect was registered. Conclusion. It has been concluded that the increase of absorbed radiation dose in

  20. An APC:WNT counter-current-like mechanism regulates cell division along the colonic crypt axis: a mechanism that explains how APC mutations induce proliferative abnormalities that drive colon cancer development.

    Directory of Open Access Journals (Sweden)

    Bruce M Boman

    2013-11-01

    Full Text Available APC normally down-regulates WNT signaling in human colon, and APC mutations cause proliferative abnormalities in premalignant crypts leading to colon cancer, but the mechanisms are unclear at the level of spatial and functional organization of the crypt. Accordingly, we postulated a counter-current-like mechanism based on gradients of factors (APC;WNT that regulate colonocyte proliferation along the crypt axis. During crypt renewal, stem cells (SCs at the crypt bottom generate non-SC daughter cells that proliferate and differentiate while migrating upwards. The APC concentration is low at the crypt bottom and high at the top (where differentiated cells reside. WNT signaling, in contrast, is high at the bottom (where SCs reside and low at the top. Given that WNT and APC gradients are counter to one another, we hypothesized that a counter-current-like mechanism exists. Since both APC and WNT signaling components (e.g. survivin are required for mitosis, this mechanism establishes a zone in the lower crypt where conditions are optimal for maximal cell division and mitosis orientation (symmetric versus asymmetric. APC haploinsufficiency diminishes the APC gradient, shifts the proliferative zone upwards, and increases symmetric division, which causes SC overpopulation. In homozygote mutant crypts, these changes are exacerbated. Thus, APC-mutation-induced changes in the counter-current-like mechanism cause expansion of proliferative populations (SCs, rapidly-proliferating cells during tumorigenesis. We propose this mechanism also drives crypt fission, functions in the crypt cycle, and underlies adenoma development. Novel chemoprevention approaches designed to normalize the two gradients and readjust the proliferative zone downwards, might thwart progression of these premalignant changes.

  1. Aberrant splicing and drug resistance in AML.

    Science.gov (United States)

    de Necochea-Campion, Rosalia; Shouse, Geoffrey P; Zhou, Qi; Mirshahidi, Saied; Chen, Chien-Shing

    2016-01-01

    The advent of next-generation sequencing technologies has unveiled a new window into the heterogeneity of acute myeloid leukemia (AML). In particular, recurrent mutations in spliceosome machinery and genome-wide aberrant splicing events have been recognized as a prominent component of this disease. This review will focus on how these factors influence drug resistance through altered splicing of tumor suppressor and oncogenes and dysregulation of the apoptotic signaling network. A better understanding of these factors in disease progression is necessary to design appropriate therapeutic strategies recognizing specific alternatively spliced or mutated oncogenic targets. PMID:27613060

  2. Comparison of the dose-response relationship of radiation-induced apoptosis in the hippocampal dentate gyrus and intestinal crypt of adult mice

    International Nuclear Information System (INIS)

    The present study compared the dose-response curves for the frequency of apoptosis in mouse hippocampal dentate gyrus (DG) and intestinal crypt using whole-body gamma irradiation. The incidence of gamma-ray-induced apoptosis was measured using the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end-labelling (TUNEL) method. TUNEL-positive apoptotic nuclei in the DG and intestinal crypt were increased in a dose-dependent pattern (0-2 Gy). The dose-response curves were linear-quadratic, with a significant relationship between the appearance of apoptosis and irradiation dose. The slopes of the dose-response curves in the DG were much steeper (∼5-6-fold) than those in the intestinal crypt within the range of 0-1 Gy exposure. Hippocampal DG might be a more effective and sensitive evaluation structure than the intestinal crypt to estimate the degree of radiation exposure in damaged organs of adult mice exposed to low irradiation dose. copy; The Author 2011. Published by Oxford Univ. Press. All rights reserved. (authors)

  3. Assessment of radial image distortion and spherical aberration on 3D synthetic aperture PIV measurements

    International Nuclear Information System (INIS)

    This paper presents a study of the effects of radial image distortion and spherical aberration on reconstruction quality of synthetic aperture particle image velocimetry (SAPIV). A simulated SAPIV system is used to image a synthetic particle volume. An idealized pinhole camera model is used for image formation with distortion and spherical aberration being added on with a polynomial model and a Fourier waveform model, respectively. Images from a simulated 5 × 5 camera array are taken, distorted or aberrated, realigned and averaged to form synthetic aperture images at a set of depths within the seeded volume. These images are thresholded to recover three-dimensional (3D) particle locations and a reconstructed 3D intensity field is formed. This reconstructed field is then evaluated according to intensity data and a signal-to-noise ratio (SNR) as well as standard and rank correlation metrics. Results show that even small amounts of image distortion and spherical aberration can lead to lower correlation values, degradation of the SNR and information loss. Use of rank correlation increases the ability to match elements between the synthetic and reconstructed volumes relative to standard correlation. (paper)

  4. MICRONUCLEI PROFILE: AN INDEX OF CHROMOSOMAL ABERRATIONS IN FRESHWATER FISHES (SYNODONTIS CLARIAS AND TILAPIA NILOTICA

    Directory of Open Access Journals (Sweden)

    J.C. OKONKWO

    2011-01-01

    Full Text Available Incidence of chromosomal aberrations in Synodontis clarias and Tilapia nilotica (Linnaeus 1757 were measured using the conventional micronucleus assay in fish erythrocytes. The species showed varying degree of micronuclei frequencies in their respective genomes of sampled gill and kidney blood. Cytological examinations showed bi-nucleated cells, deformed nuclei including the main aberrations, micronucleus formations in various genomes of the fish from different locations considered in this study. Comparison of the micronucleus rates in peripheral and kidney blood of the two species revealed no statistical difference (P> 0.05. On species occurrence of the measured chromosomal aberrations, averages of micronucleus frequencies recorded in Synodontis clarias showed visible variation and to be 2.2 folds higher than the values obtained in the corresponding Tilapia sp. but there was no statistical difference (P>0.01 among the two breeds. The work recommends that micronuclei tests in fish erythrocytes be carried out at various times, thus making it possible to follow-up the changing micronuclei frequencies and concludes that gills and kidney erythrocytes can be used in studies concerning chromosomal aberrations since the sampling of the peripheral blood is appropriate as it allows collecting several samples from the same individuals, without having to sacrifice it.

  5. Aberration measurement from specific photolithographic images: a different approach.

    Science.gov (United States)

    Nomura, H; Tawarayama, K; Kohno, T

    2000-03-01

    Techniques for measurement of higher-order aberrations of a projection optical system in photolithographic exposure tools have been established. Even-type and odd-type aberrations are independently obtained from printed grating patterns on a wafer by three-beam interference under highly coherent illumination. Even-type aberrations, i.e., spherical aberration and astigmatism, are derived from the best focus positions of vertical, horizontal, and oblique grating patterns by an optical microscope. Odd-type aberrations, i.e., coma and three-foil, are obtained by detection of relative shifts of a fine grating pattern to a large pattern by an overlay inspection tool. Quantitative diagnosis of lens aberrations with a krypton fluoride (KrF) excimer laser scanner is demonstrated.

  6. Effect of CpG-ODN combined with radiation on micronuclei cell of the human intestinal crypt epithelial cell

    International Nuclear Information System (INIS)

    In order study the changes of micronuclei cell frequency in the non-immune cell types, the human intestinal crypt epithelial cell (HIEC) was treated by CpG-ODN after radiation. MTT assay and micronuclei assay were used in this research. The result of MTT assay shows that CpG-ODN does not have any toxicity to HIEC in the concentration range of 0.00-1.25 μmol/L. Micronuclei assay measurement indicates that CpG-ODN can protect HIEC from radiation damage by reducing the micronucleus frequency (MNF) and the micronucleus cell frequency (MNCF). The experiment results reveal that CpG-ODN is safe and may have radioprotection effect on some non-immune human cell types. (authors)

  7. Drinking beer reduces radiation-induced chromosome aberrations in human lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Monobe, Manami [Chiba Univ. (Japan). Graduate School of Science and Technology; Ando, Koichi [National Inst. of Radiological Sciences, Chiba (Japan)

    2002-09-01

    We here investigated and reported the effects of beer drinking on radiation-induced chromosome aberrations in blood lymphocytes. Human blood that was collected either before or after drinking a 700 ml beer was in vitro irradiated with 200 kVp X rays or 50 keV/{mu}m carbon ions. The relation between the radiation dose and the aberration frequencies (fragments and dicentrics) was significantly (P<0.05) lower for lymphocytes collected 3 h after beer drinking than those before drinking. Fitting the dose response to a linear quadratic model showed that the alpha term of carbon ions was significantly (P<0.05) decreased by beer drinking. A decrease of dicentric formation was detected as early as 0.5 h after beer drinking, and lasted not shorter than 4.5 h. The mitotic index of lymphocytes was higher after beer drinking than before, indicating that a division delay would not be responsible for the low aberrations induced by beer drinking. An in vitro treatment of normal lymphocytes with 0.1 M ethanol, which corresponded to a concentration of 6-times higher than the maximum ethanol concentration in the blood after beer drinking, reduced the dicentric formation caused by X-ray irradiation, but not by carbon-ion irradiation. The beer-induced reduction of dicentric formation was not affected by serum. It is concluded that beer could contain non-ethanol elements that reduce the chromosome damage of lymphocytes induced by high-LET radiation. (author)

  8. Serum and fecal canine α1-proteinase inhibitor concentrations reflect the severity of intestinal crypt abscesses and/or lacteal dilation in dogs.

    Science.gov (United States)

    Heilmann, Romy M; Parnell, Nolie K; Grützner, Niels; Mansell, Joanne; Berghoff, Nora; Schellenberg, Stefan; Reusch, Claudia E; Suchodolski, Jan S; Steiner, Jörg M

    2016-01-01

    Gastrointestinal (GI) protein loss, due to lymphangiectasia or chronic inflammation, can be challenging to diagnose. This study evaluated the diagnostic accuracy of serum and fecal canine α1-proteinase inhibitor (cα1PI) concentrations to detect crypt abscesses and/or lacteal dilation in dogs. Serum and fecal cα1PI concentrations were measured in 120 dogs undergoing GI tissue biopsies, and were compared between dogs with and without crypt abscesses/lacteal dilation. Sensitivity and specificity were calculated for dichotomous outcomes. Serial serum cα1PI concentrations were also evaluated in 12 healthy corticosteroid-treated dogs. Serum cα1PI and albumin concentrations were significantly lower in dogs with crypt abscesses and/or lacteal dilation than in those without (both P <0.001), and more severe lesions were associated with lower serum cα1PI concentrations, higher 3 days-mean fecal cα1PI concentrations, and lower serum/fecal cα1PI ratios. Serum and fecal cα1PI, and their ratios, distinguished dogs with moderate or severe GI crypt abscesses/lacteal dilation from dogs with only mild or none such lesions with moderate sensitivity (56-92%) and specificity (67-81%). Serum cα1PI concentrations increased during corticosteroid administration. We conclude that serum and fecal α1PI concentrations reflect the severity of intestinal crypt abscesses/lacteal dilation in dogs. Due to its specificity for the GI tract, measurement of fecal cα1PI appears to be superior to serum cα1PI for diagnosing GI protein loss in dogs. In addition, the serum/fecal cα1PI ratio has an improved accuracy in hypoalbuminemic dogs, but serum cα1PI concentrations should be carefully interpreted in corticosteroid-treated dogs. PMID:26631946

  9. Aberration influenced generation of rotating two-lobe light fields

    Science.gov (United States)

    Kotova, S. P.; Losevsky, N. N.; Prokopova, D. V.; Samagin, S. A.; Volostnikov, V. G.; Vorontsov, E. N.

    2016-08-01

    The influence of aberrations on light fields with a rotating intensity distribution is considered. Light fields were generated with the phase masks developed using the theory of spiral beam optics. The effects of basic aberrations, such as spherical aberration, astigmatism and coma are studied. The experimental implementation of the fields was achieved with the assistance of a liquid crystal spatial light modulator HOLOEYE HEO-1080P, operating in reflection mode. The results of mathematical modelling and experiments have been qualitatively compared.

  10. Higher order aberrations of the eye: Part one

    Directory of Open Access Journals (Sweden)

    Marsha Oberholzer

    2016-03-01

    Full Text Available This article is the first in a series of two articles that provide a comprehensive literature review of higher order aberrations (HOAs of the eye. The present article mainly explains the general principles of such HOAs as well as HOAs of importance, and the measuring apparatus used to measure HOAs of the eye. The second article in the series discusses factors contributing to variable results in measurements of HOAs of the eye.Keywords: Higher order aberrations; wavefront aberrations; aberrometer

  11. Naturally Occurring Deletion Mutants of the Pig-Specific, Intestinal Crypt Epithelial Cell Protein CLCA4b without Apparent Phenotype.

    Directory of Open Access Journals (Sweden)

    Stephanie Plog

    Full Text Available The human CLCA4 (chloride channel regulator, calcium-activated modulates the intestinal phenotype of cystic fibrosis (CF patients via an as yet unknown pathway. With the generation of new porcine CF models, species-specific differences between human modifiers of CF and their porcine orthologs are considered critical for the translation of experimental data. Specifically, the porcine ortholog to the human CF modulator gene CLCA4 has recently been shown to be duplicated into two separate genes, CLCA4a and CLCA4b. Here, we characterize the duplication product, CLCA4b, in terms of its genomic structure, tissue and cellular expression patterns as well as its in vitro electrophysiological properties. The CLCA4b gene is a pig-specific duplication product of the CLCA4 ancestor and its protein is exclusively expressed in small and large intestinal crypt epithelial cells, a niche specifically occupied by no other porcine CLCA family member. Surprisingly, a unique deleterious mutation of the CLCA4b gene is spread among modern and ancient breeds in the pig population, but this mutation did not result in an apparent phenotype in homozygously affected animals. Electrophysiologically, neither the products of the wild type nor of the mutated CLCA4b genes were able to evoke a calcium-activated anion conductance, a consensus feature of other CLCA proteins. The apparently pig-specific duplication of the CLCA4 gene with unique expression of the CLCA4b protein variant in intestinal crypt epithelial cells where the porcine CFTR is also present raises the question of whether it may modulate the porcine CF phenotype. Moreover, the naturally occurring null variant of CLCA4b will be valuable for the understanding of CLCA protein function and their relevance in modulating the CF phenotype.

  12. Cellular origin of prognostic chromosomal aberrations in AML patients

    DEFF Research Database (Denmark)

    Mora-Jensen, H.; Jendholm, J.; Rapin, N.;

    2015-01-01

    karyotype have demonstrated the presence of prognostic driver aberrations (that is, NPM1, FLT3-ITD and FLT3-TKD) in committed HPCs but not in multipotent HSCs. However, the HSC populations lacking the prognostic driver aberrations contained preleukemic clones harboring a series of recurrent molecular...... aberrations that were present in the fully transformed committed HPCs together with the prognostic driver aberration. Adding to this vast heterogeneity and complexity of AML genomes and their clonal evolution, a recent study of a murine AML model demonstrated that t(9;11) AML originating from HSCs responded...

  13. Chromosome aberration analysis for biological dosimetry: a review

    International Nuclear Information System (INIS)

    Among various biological dosimetry techniques, dicentric chromosome aberration method appears to be the method of choice in analysing accidental radiation exposure in most of the laboratories. The major advantage of this method is its sensitivity as the number of dicentric chromosomes present in control population is too small and more importantly radiation induces mainly dicentric chromosome aberration among unstable aberration. This report brings out the historical development of various cytogenetic methods, the basic structure of DNA, chromosomes and different forms of chromosome aberrations. It also highlights the construction of dose-response curve for dicentric chromosome and its use in the estimation of radiation dose. (author)

  14. Environmental TEM in an Aberration Corrected Microscope

    DEFF Research Database (Denmark)

    Hansen, Thomas Willum; Wagner, Jakob Birkedal

    The increasing use of environmental transmission electron microscopy (ETEM) in materials science provides exciting new possibilities for investigating chemical reactions and understanding both the interaction of fast electrons with gas molecules and the effect of the presence of gas on high......‐resolution imaging. A gaseous atmosphere in the pole‐piece gap of the objective lens of the microscope alters both the incoming electron wave prior to interaction with the sample and the outgoing wave below the sample. Whereas conventional TEM samples are usually thin (below 10‐20 nm), the gas in the environmental......‐of‐the‐art aberration corrected TEMs provide electron micrographs with high spatial resolution. The apparent interpretability of such images encourages microscopists to analyze data more quantitatively. Such an analysis requires a detailed knowledge of the entire path and propagation of the electrons along...

  15. Statistical virtual eye model based on wavefront aberration

    OpenAIRE

    Wang, Jie-Mei; Liu, Chun-Ling; Luo, Yi-Ning; Liu, Yi-Guang; Hu, Bing-Jie

    2012-01-01

    Wavefront aberration affects the quality of retinal image directly. This paper reviews the representation and reconstruction of wavefront aberration, as well as the construction of virtual eye model based on Zernike polynomial coefficients. In addition, the promising prospect of virtual eye model is emphasized.

  16. Fifth-order aberrations in magnetic quadrupole-octupole systems

    International Nuclear Information System (INIS)

    Explicit integral expressions are given for the fifth-order geometrical aberration coefficients in rectilinear magnetic quadrupole-octupole systems used for the transport of nonrelativistic charged particle beams. The numerical values of the fifth-order geometrical aberration coefficients for a rare earth cobalt (REC) quadrupole doublet are given as an example. 26 refs., 5 figs., 4 tabs

  17. Expressions for third-order aberration theory for holographic images

    Indian Academy of Sciences (India)

    S K Tripathy; S Ananda Rao

    2003-01-01

    Expressions for third-order aberration in the reconstructed wave front of point objects are established by Meier. But Smith, Neil Mohon, Sweatt independently reported that their results differ from that of Meier. We found that coefficients for spherical aberration, astigmatism, tally with Meier’s while coefficients for distortion and coma differ.

  18. Chromosome aberration analysis based on a beta-binomial distribution

    International Nuclear Information System (INIS)

    Analyses carried out here generalized on earlier studies of chromosomal aberrations in the populations of Hiroshima and Nagasaki, by allowing extra-binomial variation in aberrant cell counts corresponding to within-subject correlations in cell aberrations. Strong within-subject correlations were detected with corresponding standard errors for the average number of aberrant cells that were often substantially larger than was previously assumed. The extra-binomial variation is accomodated in the analysis in the present report, as described in the section on dose-response models, by using a beta-binomial (B-B) variance structure. It is emphasized that we have generally satisfactory agreement between the observed and the B-B fitted frequencies by city-dose category. The chromosomal aberration data considered here are not extensive enough to allow a precise discrimination between competing dose-response models. A quadratic gamma ray and linear neutron model, however, most closely fits the chromosome data. (author)

  19. Brown's transport up to third order aberration by artificial intelligence

    International Nuclear Information System (INIS)

    Brown's TRANSPORT is a first and second order matrix multiplication computer program intended for the design of accelerator beam transport systems, neglecting the third order aberration. Recently a new method was developed to derive analytically any order aberration coefficients of general charged particle optic system, applicable to any practical systems, such as accelerators, electron microscopes, lithographs, including those unknown systems yet to be invented. An artificial intelligence program in Turbo Prolog was implemented on IBM-PC 286 or 386 machine to generate automatically the analytical expression of any order aberration coefficients of general charged particle optic system. Based on this new method and technique, Brown's TRANSPORT is extended beyond the second order aberration effect by artificial intelligence, outputting automatically all the analytical expressions up to the third order aberration coefficients

  20. Simultaneous exoplanet detection and instrument aberration retrieval in multispectral coronagraphic imaging

    CERN Document Server

    Ygouf, Marie; Mouillet, David; Fusco, Thierry; Beuzit, Jean-Luc

    2013-01-01

    High-contrast imaging for the detection and characterization of exoplanets relies on the instrument's capability to block out the light of the host star. Some current post-processing methods for calibrating out the residual speckles use information redundancy offered by multispectral imaging but do not use any prior information on the origin of these speckles. We investigate whether additional information on the system and image formation process can be used to more finely exploit the multispectral information. We developed an inversion method in a Bayesian framework that is based on an analytical imaging model to estimate both the speckles and the object map. The model links the instrumental aberrations to the speckle pattern in the image focal plane, distinguishing between aberrations upstream and downstream of the coronagraph. We propose and validate several numerical techniques to handle the difficult minimization problems of phase retrieval and achieve a contrast of 10^6 at 0.2 arcsec from simulated imag...

  1. Chromosome therapy. Correction of large chromosomal aberrations by inducing ring chromosomes in induced pluripotent stem cells (iPSCs).

    Science.gov (United States)

    Kim, Taehyun; Bershteyn, Marina; Wynshaw-Boris, Anthony

    2014-01-01

    The fusion of the short (p) and long (q) arms of a chromosome is referred to as a "ring chromosome." Ring chromosome disorders occur in approximately 1 in 50,000-100,000 patients. Ring chromosomes can result in birth defects, mental disabilities, and growth retardation if additional genes are deleted during the formation of the ring. Due to the severity of these large-scale aberrations affecting multiple contiguous genes, no possible therapeutic strategies for ring chromosome disorders have so far been proposed. Our recent study (Bershteyn et al.) using patient-derived fibroblast lines containing ring chromosomes, found that cellular reprogramming of these fibroblasts into induced pluripotent stem cells (iPSCs) resulted in the cell-autonomous correction of the ring chromosomal aberration via compensatory uniparental disomy (UPD). These observations have important implications for studying the mechanism of chromosomal number control and may lead to the development of effective therapies for other, more common, chromosomal aberrations.

  2. Changes in the transcriptional profile of transporters in the intestine along the anterior-posterior and crypt-villus axes

    Directory of Open Access Journals (Sweden)

    Delorenzi Mauro

    2005-05-01

    Full Text Available Abstract Background The purpose of this work was to characterize the expression of drug and nutrient carriers along the anterior-posterior and crypt-villus axes of the intestinal epithelium and to study the validity of utilizing whole gut tissue rather than purified epithelial cells to examine regional variations in gene expression. Results We have characterized the mRNA expression profiles of 76 % of all currently known transporters along the anterior-posterior axis of the gut. This is the first study to describe the expression profiles of the majority of all known transporters in the intestine. The expression profiles of transporters, as defined according to the Gene Ontology consortium, were measured in whole tissue of the murine duodenum, jejunum, ileum and colon using high-density microarrays. For nine transporters (Abca1, Abcc1, Abcc3, Abcg8, Slc10a2, Slc28a2, Slc2a1, Slc34a2 and Slc5a8, the mRNA profiles were further measured by RT-PCR in laser micro-dissected crypt and villus epithelial cells corresponding to the aforementioned intestinal regions. With respect to differentially regulated transporters, the colon had a distinct expression profile from small intestinal segments. The majority (59 % for p cutoff ≤ 0.05 of transporter mRNA levels were constant across the intestinal sections studied. For the transporter subclass "carrier activity", which contains the majority of known carriers for biologically active compounds, a significant change (p ≤ 0.05 along the anterior-posterior axis was observed. Conclusion All nine transporters examined in laser-dissected material demonstrated good replication of the region-specific profiles revealed by microarray. Furthermore, we suggest that the distribution characteristics of Slc5a8 along the intestinal tract render it a suitable candidate carrier for monocarboxylate drugs in the posterior portion of the intestine. Our findings also predict that there is a significant difference in the

  3. Aberrations of the cathode objective lens up to fifth order

    Energy Technology Data Exchange (ETDEWEB)

    Tromp, R.M., E-mail: rtromp@us.ibm.com [Thomas J. Watson Research Center, IBM Research Division, 1101 Kitchawan Road, P.O. Box 218, Yorktown Heights, NY 10598 (United States); Leiden University, Kamerlingh Onnes Laboratorium, P.O. Box 9504, NL-2300 RA Leiden (Netherlands); Wan, W. [Ernest Orlando Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Mailstop 80R0114, Berkeley, CA 94720 (United States); Schramm, S.M. [Leiden University, Kamerlingh Onnes Laboratorium, P.O. Box 9504, NL-2300 RA Leiden (Netherlands)

    2012-08-15

    In this paper we discuss a topic that was close to Prof. Gertrude Rempfer s interests for many years. On this occasion of her 100th birthday, we remember and honor Gertrude for her many outstanding contributions, and for the inspiring example that she set. We derive theoretical expressions for the aberration coefficients of the uniform electrostatic field up to 5th order and compare these with raytracing calculations for the cathode lens used in Low Energy Electron Microscopy and Photo Electron Emission Microscopy experiments. These higher order aberration coefficients are of interest for aberration corrected experiments in which chromatic (C{sub c}) and spherical (C{sub 3}) aberrations of the microscope are set to zero. The theoretical predictions are in good agreement with the results of raytracing. Calculations of image resolution using the Contrast Transfer Function method show that sub-nanometer resolution is achievable in an aberration corrected LEEM system. -- Highlights: Black-Right-Pointing-Pointer A theory is presented for the aberrations of the uniform electrostatic field up to fifth order. Black-Right-Pointing-Pointer Such aberrations are important for advanced LEEM and PEEM instruments. Black-Right-Pointing-Pointer Good agreement between theory and raytracing results for a full cathode objective lens. Black-Right-Pointing-Pointer Contrast Transfer Function calculations predict that spatial resolution below 1 nm is achievable.

  4. Chromosome aberrations in solid tumors have a stochastic nature

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Mauro A.A. [Departamento de Bioquimica, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2600-anexo, Porto Alegre 90035-003 (Brazil) and Departamento de Medicina Interna, Hospital de Clinicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2350, Porto Alegre 90035-903 (Brazil) and Instituto de Fisica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, Porto Alegre 91501-970 (Brazil) and Universidade Luterana do Brasil, Rua Miguel Tostes 101, Canoas 92420-280 (Brazil)]. E-mail: mauro@ufrgs.br; Onsten, Tor G.H. [Departamento de Medicina Interna, Hospital de Clinicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2350, Porto Alegre 90035-903 (Brazil); Universidade Luterana do Brasil, Rua Miguel Tostes 101, Canoas 92420-280 (Brazil); Moreira, Jose C.F. [Departamento de Bioquimica, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2600-anexo, Porto Alegre 90035-003 (Brazil); Almeida, Rita M.C. de [Instituto de Fisica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, Porto Alegre 91501-970 (Brazil)

    2006-08-30

    An important question nowadays is whether chromosome aberrations are random events or arise from an internal deterministic mechanism, which leads to the delicate task of quantifying the degree of randomness. For this purpose, we have defined several Shannon information functions to evaluate disorder inside a tumor and between tumors of the same kind. We have considered 79 different kinds of solid tumors with 30 or more karyotypes retrieved from the Mitelman Database of Chromosome Aberrations in Cancer. The Kaplan-Meier cumulative survival was also obtained for each solid tumor type in order to correlate data with tumor malignance. The results here show that aberration spread is specific for each tumor type, with high degree of diversity for those tumor types with worst survival indices. Those tumor types with preferential variants (e.g. high proportion of a given karyotype) have shown better survival statistics, indicating that aberration recurrence is a good prognosis. Indeed, global spread of both numerical and structural abnormalities demonstrates the stochastic nature of chromosome aberrations by setting a signature of randomness associated to the production of disorder. These results also indicate that tumor malignancy correlates not only with karyotypic diversity taken from different tumor types but also taken from single tumors. Therefore, by quantifying aberration spread, we could confront diverse models and verify which of them points to the most likely outcome. Our results suggest that the generating process of chromosome aberrations is neither deterministic nor totally random, but produces variations that are distributed between these two boundaries.

  5. Epigenetic aberrations and therapeutic implications in gliomas.

    Science.gov (United States)

    Natsume, Atsushi; Kondo, Yutaka; Ito, Motokazu; Motomura, Kazuya; Wakabayashi, Toshihiko; Yoshida, Jun

    2010-06-01

    Almost all cancer cells have multiple epigenetic abnormalities, which combine with genetic changes to affect many cellular processes, including cell proliferation and invasion, by silencing tumor-suppressor genes. In this review, we focus on the epigenetic mechanisms of DNA hypomethylation and CpG island hypermethylation in gliomas. Aberrant hypermethylation in promoter CpG islands has been recognized as a key mechanism involved in the silencing of cancer-associated genes and occurs at genes with diverse functions related to tumorigenesis and tumor progression. Such promoter hypermethylation can modulate the sensitivity of glioblastomas to drugs and radiotherapy. As an example, the methylation of the O6-methylguanine DNA methyltransferase (MGMT) promoter is a specific predictive biomarker of tumor responsiveness to chemotherapy with alkylating agents. Further, we reviewed reports on pyrosequencing - a simple technique for the accurate and quantitative analysis of DNA methylation. We believe that the quantification of MGMT methylation by pyrosequencing might enable the selection of patients who are most likely to benefit from chemotherapy. Finally, we also evaluated the potential of de novo NY-ESO-1, the most immunogenic cancer/testis antigen (CTA) discovered thus far, as an immunotherapy target. The use of potent epigenetics-based therapy for cancer cells might restore the abnormally regulated epigenomes to a more normal state through epigenetic reprogramming. Thus, epigenetic therapy may be a promising and potent treatment for human neoplasia.

  6. Aberrant DNA methylation in cloned ovine embryos

    Institute of Scientific and Technical Information of China (English)

    LIU Lei; HOU Jian; LEI TingHua; BAI JiaHua; GUAN Hong; AN XiaoRong

    2008-01-01

    By using the approach of immunofluorescence staining with an antibody against 5-methylcytosine (5MeC), the present study detected the DNA methylation patterns of cloned ovine embryos. The em-bryos derived from in vitro fertilization were also examined for reference purpose. The results showed that: (1) during the pre-implantation development, cloned embryos displayed a similar demethylation profile to the fertilized embryos; that is, the methylation level decreased to the lowest at 8-cell stage, and then increased again at morulae stage. However, methylation level was obviously higher in cloned embryos than in stage-matched fertilized embryos, especially at 8-cell stage and afterwards; (2) at blastocyst stage, the methylation pattern in cloned embryos was different from that in fertilized em-bryos. In cloned blastocyst, inner cell mass (ICM) exhibited a comparable level to trophectoderm cells (TE), while in in-vitro fertilized blastocyst the methylation level of ICM was lower than that of TE, which is not consistent with that reported by other authors. These results indicate that DNA methylation is abnormally reprogrammed in cloned embryos, implying that aberrant DNA methylation reprogramming may be one of the factors causing cloned embryos developmental failure.

  7. The secretory KCa1.1 channel localises to crypts of distal mouse colon: functional and molecular evidence

    DEFF Research Database (Denmark)

    Sørensen, Mads Vaarby; Strandsby, Anne Bystrup; Larsen, Casper Kornbech;

    2011-01-01

    Na+ absorption is mediated by epithelial Na+ channel (ENaC) in surface cells. Previously, we identified the large conductance Ca2+-activated K+ channel, KCa1.1 or big potassium (BK) channel, as the only relevant K+ secretory pathway in mouse distal colon. The exact localisation of K(Ca)1.1 channels......) is expressed primarily in the crypts and γ-ENaC primarily in the surface cells. The KCa1.1 α-subunit mRNA was like NKCC1, mainly expressed in the crypts. The crypt to surface expression pattern of the channels and transporters was not altered when plasma aldosterone was elevated. The mRNA levels for NKCC1, γ-ENa......C and KCa1.1 α-subunit were, however, under these circumstances substantially augmented (KCa1.1 α-subunit, twofold; NKCC1, twofold and ENaC, tenfold). Functionally, we show that ENaC-mediated Na+ absorption and BK channel-mediated K+ secretion are two independent processes. These findings show that KCa1...

  8. The identification of high and low risk groups for colorectal cancer using rectal mucosal crypt cell production rate (CCPR).

    Science.gov (United States)

    Rooney, P S; Clarke, P A; Gifford, K A; Hardcastle, J D; Armitage, N C

    1993-07-01

    Rectal mucosal proliferation was measured in 116 individuals using the metaphase arrest technique crypt cell production rate (CCPR). CCPR was found to be significantly elevated in individuals with adenomas (n = 42, CCPR = 13 cc c-1h-1, range 7-25 Cl 10-15) compared with normals (n = 21, CCPR = 10 cc c-1h-1 range 5-24 Cl 7-11, Mann-Whitney P = 0.001 z = 3.2). Mucosal proliferation was increased among individuals who were undergoing adenoma follow up but in whom no further adenomas were found (n = 37 CCPR = 12 range 5-26 cc c-1h-1 Cl 10-14) compared to controls (Mann-Whitney P = 0.01 z = 2.4) Proliferation in vegetarians i.e. low risk (n = 16) was similar to controls. Measurement of proliferative indices in rectal mucosa by the stathmokinetic technique CCPR can discriminate between high and low risk groups for colorectal cancer. PMID:8318409

  9. Study of residual aberration for non-imaging focusing heliostat

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Y.T.; Chong, K.K.; Lim, B.H.; Lim, C.S. [Institute of Energy and Environment, Malaysia University of Science and Technology, No. 17, Jalan SS7/26, Kelana Jaya, 47301 Petaling Jaya, Selangor (Malaysia)

    2003-08-01

    Instead of using a specific focusing geometry, a non-imaging focusing heliostat has no fixed geometry but is composed of many small movable element mirrors that can be manoeuvred to eliminate the first-order aberration. Following our previous publication on the principle of non-imaging focusing heliostat, this paper further explores higher order residual aberration that limits the size of the focusing spot. The residual aberration can be partially corrected by offsetting the pivot point of mirrors and pre-setting the tilting angles of mirrors.

  10. Semiclassical TEM image formation in phase space

    Energy Technology Data Exchange (ETDEWEB)

    Lubk, Axel; Röder, Falk

    2015-04-15

    Current developments in TEM such as high-resolution imaging at low acceleration voltages and large fields of view, the ever larger capabilities of hardware aberration correction and the systematic shaping of electron beams require accurate descriptions of TEM imaging in terms of wave optics. Since full quantum mechanic solutions have not yet been established for, e.g., the theory of aberrations, we are exploring semiclassical image formation in the TEM from the perspective of quantum mechanical phase space, here. Firstly, we use two well-known semiclassical approximations, Miller's semiclassical algebra and the frozen Gaussian method, for describing the wave optical generalization of arbitrary geometric aberrations, including nonisoplanatic and slope aberrations. Secondly, we demonstrate that the Wigner function representation of phase space is well suited to also describe incoherent aberrations as well as the ramifications of partial coherence due to the emission process at the electron source. We identify a close relationship between classical phase space and Wigner function distortions due to aberrations as well as classical brightness and quantum mechanical purity. - Highlights: • We discuss several semiclassical approximations to describe image formation in the TEM. • We provide laws how aberrations modify quantum mechanical phase space. • We exhibit the close relation between quantum mechanical purity and axial brightness.

  11. Aberrations of Genetic Material as Biomarkers of Ionizing Radiation Effects

    Energy Technology Data Exchange (ETDEWEB)

    Milacic, S.

    2004-07-01

    Ionizing radiation is the most powerful mutagen in environmental and working conditions. The result of genotoxic effect of radiation is the development of chromosome aberrations. The structural chromosome aberrations in peripheral blood lymphocytes are dicentric, ring, acentric fragment. The observation of chromosome aberration frequency in lymphocyte karyotype is the conclusive method to assess the absorbed dose of ionizing radiation. Our study compared the incidence of chromosome aberrations in occupationally exposed healthy medical workers and in non-exposed healthy population. We analyzed the effect of working place, dose by thermo luminescence personal dosimeter (TLD), duration of occupational exposure (DOE) and age to the sum of aberrant cells and aberrations. four-year study included 462 subjects, mean-aged 42.3 years, who were occupational exposed to ionizing radiation and 95 subjects, mean-aged 35,2 years, who were not exposed to ionizing radiation, during the same time period and from the same territory. All of them possess thermo luminescence personal dosimeter (TLD) which is read by scanner for thermo luminescence dosimeters. Modified Moorheard's micro method for peripheral blood lymphocytes and conventional cytogenetic technique of chromosome aberration analysis were used for analysis of chromosome aberrations. Stained preparations (Giemsa) are observed in immersion by light microscope. The karyotype of 200 lymphocytes in metaphase is analyzed the most characteristic aberration: dicentric, then the ring and acentric fragments. The increased incidence of chromosome aberrations was found to tbe 21.6% in the exposed group and 2.1% in the controls, while the findings within the limits (non-specific chromosome lesions-gaps breaks, elongations, and exchanges) were equal in both groups (22%). Among occupationally exposed medical workers, the highest incidence was found in nuclear medicine workers (42.6%), then in orthopedists (27.08%). There is highly

  12. High order aberration and straylight evaluation after cataract surgery with implantation of an aspheric,aberration correcting monofocal intraocular lens

    Institute of Scientific and Technical Information of China (English)

    Florian; T; A; Kretz; Tamer; Tandogan; Ramin; Khoramnia; Gerd; U; Auffarth

    2015-01-01

    ·AIM: To evaluate the quality of vision in respect to high order aberrations and straylight perception after implantation of an aspheric, aberration correcting,monofocal intraocular lens(IOL).·METHODS: Twenty-one patients(34 eyes) aged 50 to83 y underwent cataract surgery with implantation of an aspheric, aberration correcting IOL(Tecnis ZCB00,Abbott Medical Optics). Three months after surgery they were examined for uncorrected(UDVA) and corrected distance visual acuity(CDVA), contrast sensitivity(CS)under photopic and mesopic conditions with and without glare source, ocular high order aberrations(HOA, Zywave II) and retinal straylight(C-Quant).· RESULTS: Postoperatively, patients achieved a postoperative CDVA of 0.0 log MAR or better in 97.1% of eyes. Mean values of high order abberations were +0.02±0.27(primary coma components) and-0.04 ±0.16(spherical aberration term). Straylight values of the C-Quant were 1.35±0.44 log which is within normal range of age matched phakic patients. The CS measurements under mesopic and photopic conditions in combination with and without glare did not show any statistical significance in the patient group observed(P ≥0.28).· CONCLUSION: The implantation of an aspherical aberration correcting monofocal IOL after cataractsurgery resulted in very low residual higher order aberration(HOA) and normal straylight.

  13. Aberrant retropharyngeal internal carotid artery associated with retropharyngeal abscess: determination of a safe drainage zone with computed tomography

    International Nuclear Information System (INIS)

    Full text: Introduction: During surgery, interventional procedures and anesthesia-related actions, awareness of the aberrant course of the internal carotid artery (ICA) may prevent vascular damage and massive hemorrhage. Objectives and tasks: To emphasize the importance of guiding of the imaging performed before the interventional procedures, in the light of the computed tomography (CT) findings of a case with aberrant retropharingeal ICA associated with retropharyngeal abscess. Materials and methods: A 60-year-old woman visited the Ear Nose and Throat (ENT) department of our hospital complaining of sore throat that persisted since 2 weeks. She was prescribed oral antibiotherapy, during which she experienced dysphagia and increasing fever. After endoscopic study, a retropharyngeal abscess was detected and was thought to be due to the bulging of the right posterior pharyngeal wall that has smooth and intact mucosa. Results: On CT, we observed an abscess formation, and enlargement of the right retropharyngeal space. CT images also displayed an aberrant course of the right ICA that was very close to the right posteromedial wall of the pharynx. After obtaining detailed anatomical information from the CT, abscess drainage from the right superolateral wall of the nasopharynx was performed at the ENT department. No hemorrhagic or other complications were encountered. On control CT examination performed 20 days after drainage, no abscess formation was seen. Conclusion: Imaging studies can show and confirm the aberrant course of the ICA, thereby reducing the risk of hemorrhagic complications

  14. A genome-wide map of aberrantly expressed chromosomal islands in colorectal cancer

    Directory of Open Access Journals (Sweden)

    Castanos-Velez Esmeralda

    2006-09-01

    Full Text Available Abstract Background Cancer development is accompanied by genetic phenomena like deletion and amplification of chromosome parts or alterations of chromatin structure. It is expected that these mechanisms have a strong effect on regional gene expression. Results We investigated genome-wide gene expression in colorectal carcinoma (CRC and normal epithelial tissues from 25 patients using oligonucleotide arrays. This allowed us to identify 81 distinct chromosomal islands with aberrant gene expression. Of these, 38 islands show a gain in expression and 43 a loss of expression. In total, 7.892 genes (25.3% of all human genes are located in aberrantly expressed islands. Many chromosomal regions that are linked to hereditary colorectal cancer show deregulated expression. Also, many known tumor genes localize to chromosomal islands of misregulated expression in CRC. Conclusion An extensive comparison with published CGH data suggests that chromosomal regions known for frequent deletions in colon cancer tend to show reduced expression. In contrast, regions that are often amplified in colorectal tumors exhibit heterogeneous expression patterns: even show a decrease of mRNA expression. Because for several islands of deregulated expression chromosomal aberrations have never been observed, we speculate that additional mechanisms (like abnormal states of regional chromatin also have a substantial impact on the formation of co-expression islands in colorectal carcinoma.

  15. Methods for the Analyses of Inhibitor-Induced Aberrant Multimerization of HIV-1 Integrase

    Science.gov (United States)

    Kessl, Jacques J.; Sharma, Amit; Kvaratskhelia, Mamuka

    2016-01-01

    HIV-1 integrase (IN) is an important therapeutic target as its function is essential for the viral lifecycle. The discovery of multifunctional allosteric IN inhibitors or ALLINIs, which potently impair viral replication by promoting aberrant, higher order IN multimerization as well as inhibit IN interactions with its cellular cofactor, LEDGF/p75, has opened new venues to exploit IN multimerization as a therapeutic target. Furthermore, the recent discovery of multimerization selective IN inhibitors or MINIs, has provided new investigational probes to study the direct effects of aberrant IN multimerization in vitro and in infected cells. Here we describe three complementary methods designed to detect and quantify the effects of these new classes of inhibitors on IN multimerization. These methods include a homogenous time-resolved fluorescence-based assay which allows for measuring EC50 values for the inhibitor-induced aberrant IN multimerization, a dynamic light scattering-based assay which allows for monitoring the formation and sizes of oligomeric IN particles in a time-dependent manner, and a chemical cross-linking-based assay of interacting IN subunits which allows for the determination of IN oligomers in viral particles. PMID:26714710

  16. Anisoplanatism in adaptive optics systems due to pupil aberrations

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, B

    2005-08-01

    Adaptive optics systems typically include an optical relay that simultaneously images the science field to be corrected and also a set of pupil planes conjugate to the deformable mirror of the system. Often, in the optical spaces where DM's are placed, the pupils are aberrated, leading to a displacement and/or distortion of the pupil that varies according to field position--producing a type of anisoplanatism, i.e., a degradation of the AO correction with field angle. The pupil aberration phenomenon is described and expressed in terms of Seidel aberrations. An expression for anisoplanatism as a function of pupil distortion is derived, an example of an off-axis parabola is given, and a convenient method for controlling pupil-aberration-generated anisoplanatism is proposed.

  17. Impact of primary aberrations on coherent lidar performance

    DEFF Research Database (Denmark)

    Hu, Qi; Rodrigo, Peter John; Iversen, Theis Faber Quist;

    2014-01-01

    In this work we investigate the performance of a monostatic coherent lidar system in which the transmit beam is under the influence of primary phase aberrations: spherical aberration (SA) and astigmatism. The experimental investigation is realized by probing the spatial weighting function...... of the lidar system using different optical transceiver configurations. A rotating belt is used as a hard target. Our study shows that the lidar weighting function suffers from both spatial broadening and shift in peak position in the presence of aberration. It is to our knowledge the first experimental...... effciency, the optimum truncation of the transmit beam and the spatial sensitivity of a CW coherent lidar system. Under strong degree of aberration, the spatial confinement is significantly degraded. However for SA, the degradation of the spatial confinement can be reduced by tuning the truncation...

  18. Chromosome aberrations in pesticide-exposed greenhouse workers

    DEFF Research Database (Denmark)

    Lander, B F; Knudsen, Lisbeth E.; Gamborg, M O;

    2000-01-01

    OBJECTIVES: The aim of this study was to investigate the possibility of subtoxic exposure to pesticides causing chromosome aberrations in greenhouse workers. METHODS: In a cross-sectional and prospective study design chromosome aberration frequencies in cultured lymphocytes were examined for 116...... greenhouse workers exposed to a complex mixture of almost 50 insecticides, fungicides, and growth regulators and also for 29 nonsmoking, nonpesticide-exposed referents. RESULTS: The preseason frequencies of chromosome aberrations were slightly but not statistically significantly elevated for the greenhouse...... workers when they were compared with the referents. After a summer season of pesticide spraying in the greenhouses, the total frequencies of cells with chromosome aberrations were significantly higher than in the preseason samples (P=0.02) and also higher than for the referents (P=0.05). This finding...

  19. Aberrant internal carotid artery in the middle ear

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Keun Tak; Kang, Hyun Koo [Dept. of Radiology, Seoul Veterans Hospital, Seoul (Korea, Republic of)

    2014-10-15

    The knowledge about the aberrant internal carotid artery (ICA) in the middle ear is essential for clinicians, because a misdiagnosis of the aberrant ICA could have serious consequences such as excessive aural bleeding during a middle ear surgery. A 38-year-old woman presented with tinnitus and hearing difficulties of the left ear that had started 5 years ago. During otoscopy, an anteroinferior bluish mass was seen in the tympanic space. Computed tomography and magnetic resonance imaging demonstrated a left-side aberrant ICA with bony dehiscence of the carotid canal in the middle ear and a reduced diameter of the tympanic ICA. Herein we report a case of an aberrant ICA in the middle ear. We also review the literature regarding this important vascular anomaly of the temporal bone which may lead to disastrous surgical complications.

  20. CT of ruptured aneurysm of aberrant right subclavian artery.

    Science.gov (United States)

    Vega, A; Ortíz, A; Longo, J M; Pagola, M A

    1987-01-01

    This paper presents the first description of a ruptured aneurysm of an aberrant right subclavian artery. CT clearly demonstrated the vascular malformation as well as the existence of a bilateral hemothorax. PMID:3102065

  1. Moment aberrations in magneto-electrostatic plasma lenses (computer simulation)

    CERN Document Server

    Butenko, V I

    2001-01-01

    In this work moment aberrations in the plasma magneto-electrostatic lenses are considered in more detail with the use of the computer modeling. For solution of the problem we have developed a special computer code - the model of plasma optical focusing device, allowing to display the main parameters and operations of experimental sample of a lens, to simulate the moment and geometrical aberrations and give recommendations on their elimination.

  2. Photothermal Lens Aberration Effects in Two Laser Thermal Lens Spectrometry

    OpenAIRE

    Bialkowski, Stephen E.

    1985-01-01

    A comparison of theories describing two laser photothermal lens signals is given. The aberrant nature of this lens is accounted for in a theory which treats the propagation of a monitor laser in terms of a phase shift in this laser beam wave front. The difference between theories are discussed in terms of the predicted signal strengths and temporal behavior. The aberrant theory results in smaller theoretical signal strengths and different functional relationships between signal and analyte le...

  3. Aberrant cervical thymus mimicking thyroid on ultrasonography: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Sub; Park, Ju Hyun; Kim, Bong Soo; Park, Ji Kang; Choi, Jae Hyuck [Jeju National Univ. Hospital/Jeju National Univ. School of Medicine, Jeju (Korea, Republic of)

    2012-10-15

    Aberrant cervical thymus is rarely reported in adults. We report a case of solid aberrant cervical thymus in a 27 year old female, which was found incidentally on ultrasonography for the evaluation of the thyroid cancer. On ultrasonography, the lesion was found between the left thyroid and common carotid artery without any remarkable interface echo, and had similar echogenicity to the thyroid. The lesion extended to the upper pole of the left thyroid.

  4. Dimensions of driving anger and their relationships with aberrant driving.

    Science.gov (United States)

    Zhang, Tingru; Chan, Alan H S; Zhang, Wei

    2015-08-01

    The purpose of this study was to investigate the relationship between driving anger and aberrant driving behaviours. An internet-based questionnaire survey was administered to a sample of Chinese drivers, with driving anger measured by a 14-item short Driving Anger Scale (DAS) and the aberrant driving behaviours measured by a 23-item Driver Behaviour Questionnaire (DBQ). The results of Confirmatory Factor Analysis demonstrated that the three-factor model (hostile gesture, arrival-blocking and safety-blocking) of the DAS fitted the driving anger data well. The Exploratory Factor Analysis on DBQ data differentiated four types of aberrant driving, viz. emotional violation, error, deliberate violation and maintaining progress violation. For the anger-aberration relation, it was found that only "arrival-blocking" anger was a significant positive predictor for all four types of aberrant driving behaviours. The "safety-blocking" anger revealed a negative impact on deliberate violations, a finding different from previously established positive anger-aberration relation. These results suggest that drivers with different patterns of driving anger would show different behavioural tendencies and as a result intervention strategies may be differentially effective for drivers of different profiles.

  5. Ocular aberrations after wavefront optimized LASIK for myopia

    Directory of Open Access Journals (Sweden)

    Padmanabhan Prema

    2010-01-01

    Full Text Available Purpose: To study the change in ocular aberrations after wavefront optimized (WFO laser in situ keratomileusis ( Lasik for correction of myopia and to analyze causative factors that may influence them. Materials and Methods: This was a prospective case series. WFO Lasik was performed for the correction of myopia, using the hansatome (Bausch and Lomb microkeratome to create the flap and the Allegretto laser (Wavelight Technologie to perform the ablation. The Allegretto wave analyser (Tscherning-type measured the ocular aberrations prior to Lasik , one month and six months postoperatively. Results: The mean age of the 59 patients included in the study was 25±5.64 years and the mean spherical equivalent of the 117 eyes that underwent Lasik0 was -5.33±1.22 preoperatively and -0.21±0.38 postoperatively. Hundred and two eyes of 117 (87% achieved uncorrected visual acuity (UCVA of 20/20 or better after WFO Lasik and 104 of 117 eyes (89% were within ±0.5D of the attempted refractive correction. There was a 1.96-fold increase in total root-mean-square of higher order aberrations. Induced changes in seven of the 22 higher order Zernike terms showed a significant linear correlation with the refractive correction attempted. Larger ablation zones induced less spherical aberration. Conclusion: In spite of an excellent visual outcome, WFO Lasik induces significant higher order aberrations. Large ablation zones reduce the induction of spherical aberration.

  6. The cAMP-regulated and 293B-inhibited K+ conductance of rat colonic crypt base cells.

    Science.gov (United States)

    Warth, R; Riedemann, N; Bleich, M; Van Driessche, W; Busch, A E; Greger, R

    1996-05-01

    We have shown previously that secretagogues acting via the second messenger adenosine 3',5'-cyclic monophosphate (cAMP) activate, besides their marked effect on the luminal Cl- conductance, a K+ conductance in the basolateral membrane of colonic crypt cells. This conductance is blocked by the chromanol 293B. This K+ conductance is examined here in more detail in cell-attached (c.a.) and cell-excised (c.e.) patch- clamp studies. Addition of forskolin (5 micromol/l) to the bath led to the activation of very small-conductance (probably Hz (n = 30). The current/voltage curves of this noise indicated that the underlying ion channels were K+ selective. 293B reduced the power density of the noise (So) to 46 +/- 8.7% of its control value and shifted fc from 291 +/- 26 to 468 +/- 54 Hz (n = 8). In c.e. patches from cells previously stimulated by forskolin, the same type of current persisted in 3 out of 18 experiments when the bath solution was a cytosolic-type solution without adenosine 5'-triphosphate (ATP) (CYT). In 15 experiments the addition of ATP (1 mmol/l) to CYT solution was necessary to induce or augment channel activity. In six experiments excision was performed into CYT + ATP solution and channel activity persisted. 293B exerted a reversible inhibitory effect. The channel activity was reduced by 5 mmol/l Ba2+ and was completely absent when K+ in the bath was replaced by Na+. These data suggest that forskolin activates a K+ channel of very small conductance which can be inhibited directly and reversibly by 293B.

  7. Transcranial phase aberration correction using beam simulations and MR-ARFI

    International Nuclear Information System (INIS)

    Purpose: Transcranial magnetic resonance-guided focused ultrasound surgery is a noninvasive technique for causing selective tissue necrosis. Variations in density, thickness, and shape of the skull cause aberrations in the location and shape of the focal zone. In this paper, the authors propose a hybrid simulation-MR-ARFI technique to achieve aberration correction for transcranial MR-guided focused ultrasound surgery. The technique uses ultrasound beam propagation simulations with MR Acoustic Radiation Force Imaging (MR-ARFI) to correct skull-caused phase aberrations. Methods: Skull-based numerical aberrations were obtained from a MR-guided focused ultrasound patient treatment and were added to all elements of the InSightec conformal bone focused ultrasound surgery transducer during transmission. In the first experiment, the 1024 aberrations derived from a human skull were condensed into 16 aberrations by averaging over the transducer area of 64 elements. In the second experiment, all 1024 aberrations were applied to the transducer. The aberrated MR-ARFI images were used in the hybrid simulation-MR-ARFI technique to find 16 estimated aberrations. These estimated aberrations were subtracted from the original aberrations to result in the corrected images. Each aberration experiment (16-aberration and 1024-aberration) was repeated three times. Results: The corrected MR-ARFI image was compared to the aberrated image and the ideal image (image with zero aberrations) for each experiment. The hybrid simulation-MR-ARFI technique resulted in an average increase in focal MR-ARFI phase of 44% for the 16-aberration case and 52% for the 1024-aberration case, and recovered 83% and 39% of the ideal MR-ARFI phase for the 16-aberrations and 1024-aberration case, respectively. Conclusions: Using one MR-ARFI image and noa priori information about the applied phase aberrations, the hybrid simulation-MR-ARFI technique improved the maximum MR-ARFI phase of the beam's focus

  8. Transcranial phase aberration correction using beam simulations and MR-ARFI

    Energy Technology Data Exchange (ETDEWEB)

    Vyas, Urvi, E-mail: urvi.vyas@gmail.com; Kaye, Elena; Pauly, Kim Butts [Department of Radiology, Stanford University, Stanford, California 94305 (United States)

    2014-03-15

    Purpose: Transcranial magnetic resonance-guided focused ultrasound surgery is a noninvasive technique for causing selective tissue necrosis. Variations in density, thickness, and shape of the skull cause aberrations in the location and shape of the focal zone. In this paper, the authors propose a hybrid simulation-MR-ARFI technique to achieve aberration correction for transcranial MR-guided focused ultrasound surgery. The technique uses ultrasound beam propagation simulations with MR Acoustic Radiation Force Imaging (MR-ARFI) to correct skull-caused phase aberrations. Methods: Skull-based numerical aberrations were obtained from a MR-guided focused ultrasound patient treatment and were added to all elements of the InSightec conformal bone focused ultrasound surgery transducer during transmission. In the first experiment, the 1024 aberrations derived from a human skull were condensed into 16 aberrations by averaging over the transducer area of 64 elements. In the second experiment, all 1024 aberrations were applied to the transducer. The aberrated MR-ARFI images were used in the hybrid simulation-MR-ARFI technique to find 16 estimated aberrations. These estimated aberrations were subtracted from the original aberrations to result in the corrected images. Each aberration experiment (16-aberration and 1024-aberration) was repeated three times. Results: The corrected MR-ARFI image was compared to the aberrated image and the ideal image (image with zero aberrations) for each experiment. The hybrid simulation-MR-ARFI technique resulted in an average increase in focal MR-ARFI phase of 44% for the 16-aberration case and 52% for the 1024-aberration case, and recovered 83% and 39% of the ideal MR-ARFI phase for the 16-aberrations and 1024-aberration case, respectively. Conclusions: Using one MR-ARFI image and noa priori information about the applied phase aberrations, the hybrid simulation-MR-ARFI technique improved the maximum MR-ARFI phase of the beam's focus.

  9. Persistence of Early Emerging Aberrant Behavior in Children with Developmental Disabilities

    Science.gov (United States)

    Green, Vanessa A.; O'Reilly, Mark; Itchon, Jonathan; Sigafoos, Jeff

    2005-01-01

    This study examined the persistence of early emerging aberrant behavior in 13 preschool children with developmental disabilities. The severity of aberrant behavior was assessed every 6 months over a 3-year period. Teachers completed the assessments using the Aberrant Behavior Checklist [Aman, M. G., & Singh, N. N. (1986). "Aberrant Behavior…

  10. Optical aberrations of intraocular lenses measured in vivo and in vitro

    Science.gov (United States)

    Barbero, Sergio; Marcos, Susana; Jiménez-Alfaro, Ignacio

    2003-10-01

    Corneal and ocular aberrations were measured in a group of eyes before and after cataract surgery with spherical intraocular lens (IOL) implantation by use of well-tested techniques developed in our laboratory. By subtraction of corneal from total aberration maps, we also estimated the optical quality of the intraocular lens in vivo. We found that aberrations in pseudophakic eyes are not significantly different from aberrations in eyes before cataract surgery or from previously reported aberrations in healthy eyes of the same age. However, aberrations in pseudophakic eyes are significantly higher than in young eyes. We found a slight increase of corneal aberrations after surgery. The aberrations of the IOL and the lack of balance of the corneal spherical aberrations by the spherical aberrations of the intraocular lens also degraded the optical quality in pseudophakic eyes. We also measured the aberrations of the IOL in vitro, using an eye cell model, and simulated the aberrations of the IOL on the basis of the IOL's physical parameters. We found a good agreement among in vivo, in vitro, and simulated measures of spherical aberration: Unlike the spherical aberration of the young crystalline lens, which tends to be negative, the spherical aberration of the IOL is positive and increases with lens power. Computer simulations and in vitro measurements show that tilts and decentrations might be contributors to the increased third-order aberrations in vivo in comparison with in vitro measurements.

  11. Advancement Study of Defence Function of Tonsil Crypt Epithelial%扁桃体隐窝上皮屏障功能研究进展

    Institute of Scientific and Technical Information of China (English)

    魏璐璐; 胡文健; 陈隆晖

    2011-01-01

    目前认为慢性扁桃体炎有3种学说,一是细菌感染,二是自身变态反应,三是免疫功能低下.一般认为发病多由急性扁桃体炎反复发作或隐窝引流不畅,窝内细菌或病毒滋生繁殖而演变为慢性炎症.近年来,国内外研究扁桃体隐窝上皮屏障功能,认为扁桃体隐窝上皮的屏障作用是决定扁桃体能否发生慢性扁桃体炎的重要原因,扁桃体隐窝上皮屏障功能的恢复,在慢性扁桃体炎的治疗中作用尤为重要.隐窝上皮是腭扁桃体中最先接触和摄取抗原,并引起免疫应答的部位,隐窝的特殊结构决定了扁桃体的功能主要是潴留过路的抗原,供免疫系统处置,因此隐窝上皮结构是扁桃体行使免疫功能的重要组织保障.慢性炎症病变使扁桃体隐窝上皮发生进行性破坏,使扁桃体产生的免疫球蛋白减少,因而不能发挥有效的免疫保护作用,所以任何治愈慢性扁桃体炎的保守措施,从组织学上首先必须恢复隐窝上皮的屏障结构.近几年来,有关慢性扁桃体炎的发病机制研究发展迅速,文献检索表明,现在还没有同类方法表明扁桃体隐窝上皮屏障功能改变对慢性扁桃体炎有影响的研究报道.文章就扁桃体隐窝上皮屏障功能作一综述.%Currently there are three theories about chronic tonsillitis: first, bacterial infection, and second, their allergy and the third is immunocompromised. It is generally believed that the incidence of recurrent acute tonsillitis by the poor drainage or crypt, nest breeding of bacteria or virus to evolve into chronic inflammation. In recent years, study abroad in the tonsil crypt epithelial barrier function found that the tonsil crypt epithelial barrier function is important to determine whether chronic tonsillitis occur. Tonsil crypt epithelial barrier function recovery and healing in the treatment of chronic tonsillitis are particularly important. Palatine tonsil crypt epithelium is the

  12. Refined carbohydrate enhancement of aberrant crypt foci (ACF) in rat colon induced by the food-borne carcinogen 2-amino-3-methyl-imidazo[4,5-f]quinoline (IQ)

    DEFF Research Database (Denmark)

    Kristiansen, E.; Meyer, Otto A.; Thorup, I.

    1996-01-01

    . In the present study it is shown that a feeding regimen with continuous low IQ doses (0.03% in the diet) throughout a study period of 10 weeks has a significant effect on the induction of ACF in the colon of male F344 rats. In addition, the study illustrates that the incidence of the IQ-induced ACF can...... be modulated by the amount of refined carbohydrates in the diet. Rats given a high sucrose/dextrin diet showed a significantly higher number of ACF compared to rats given a diet high in starches. The effect on tumor outcome will await the termination of a ongoing parallel study.......,2-dimethylhydrazine dihydrochloride (DMH) and azoxymethane (AOM), the use of a diet-related colon cancer initiator, such as the heterocyclic amine 2-amino-3-methyl-imidazo[4,5-f]quinoline (IQ) formed during meat cooking, would probably give a more relevant insight into diet-related colon carcinogenesis...

  13. Evaluation of radiosensitivity of human tumor cells after irradiation of γ-rays based on G2-chromosome aberrations

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The aim of the present investigation is to determine initial G2-chromosome aberrations and to validate whether the G2-chromosome aberrations can predict the cellular clonogenic survival in human tumor cell lines. Cell lines of human ovary carcinoma cells (HO8910) and human hepatoma cells (HepG2) were irradiated with a range of doses and assessed both for initial G2-chromosome aberrations and for cell survival after γ-irradiation. The initial G2-chromosome aberrations were measured by counting the number of G2-chromatid breaks after irradiation, detected by the premature chromosome condensation technique, and the G2-assay method. Cell survival was documented by a colony formation assay. A linear-quadratic survival curve was observed in both cell lines. The dose-response results show that the numbers of G2-chromatid breaks increase with the increase in dose in the two cell lines. At higher doses (higher than 4 Gy) of irradiation, the number of G2-chromatid breaks for the G2-assay method cannot be determined because too few cells reach mitosis, and hence their detection is difficult. A good correlation is found between the clonogenic survival and the radiation-induced initial G2-chromatid breaks per cell (r=0.9616). The present results suggest that the premature chromosome condensation technique may be useful for determining chromatid breaks in G2 cells, and the number of initial G2-chromatid breaks holds promise for predicting the radiosensitivity of tumor cells.

  14. Antimutagenic potential of curcumin on chromosomal aberrations in Allium cepa

    Institute of Scientific and Technical Information of China (English)

    RAGUNATHAN Irulappan; PANNEERSELVAM Natarajan

    2007-01-01

    Turmeric has long been used as a spice and food colouring agent in Asia. In the present investigation, the antimutagenic potential of curcumin was evaluated in Allium cepa root meristem cells. So far there is no report on the biological properties of curcumin in plant test systems. The root tip cells were treated with sodium azide at 200 and 300 μg/ml for 3 h and curcumin was given at 5, 10 and 20 μg/ml for 16 h, prior to sodium azide treatment. The tips were squashed after colchicine treatment and the cells were analyzed for chromosome aberration and mitotic index. Curcumin induces chromosomal aberration in Allium cepa root tip cells in an insignificant manner, when compared with untreated control. Sodium azide alone induces chromosomal aberrations significantly with increasing concentrations. The total number of aberrations was significantly reduced in root tip cells pretreated with curcumin. The study reveals that curcumin has antimutagenic potential against sodium azide induced chromosomal aberrations in Allium cepa root meristem cells. In addition, it showed mild cytotoxicity by reducing the percentage of mitotic index in all curcumin treated groups, but the mechanism of action remains unknown. The antimutagenic potential of curcumin is effective at 5 μg/ml in Allium cepa root meristem cells.

  15. Disruption of Tgfbr2 in odontoblasts leads to aberrant pulp calcification.

    Science.gov (United States)

    Ahn, Y H; Kim, T H; Choi, H; Bae, C H; Yang, Y M; Baek, J A; Lee, J C; Cho, E S

    2015-06-01

    Transforming growth factor β (TGF-β) signaling has been implicated in dentin formation and repair; however, the molecular mechanisms underlying dentin formation remain unclear. To address the role of TGF-β signaling in dentin formation, we analyzed odontoblast-specific Tgfbr2 conditional knockout mice. The mutant mice had aberrant teeth with thin dysplastic dentin and pulpal obliteration, similar to teeth from human patients with dentinogenesis imperfecta type II and dentin dysplasia. In mutant, the odontoblasts lost their cellular polarity, and matrix secretion was disrupted after mantle dentin formation. As a consequence, the amount of predentin decreased significantly, and an ectopic fibrous matrix was formed below the odontoblast layer. This matrix gradually calcified and obliterated the pulp chamber with increasing age. Immunohistochemistry revealed decreased expression of alkaline phosphatase in mutant odontoblasts. In mutant dentin, Dsp expression was reduced, but Dmp1 expression increased significantly. Collagen type I, biglycan, and Dsp were expressed in the ectopic matrix. These results suggest that loss of responsiveness to TGF-β in odontoblasts results in impaired matrix formation and pulpal obliteration. Our study indicates that TGF-β signaling plays an important role in dentin formation and pulp protection. Furthermore, our findings may provide new insight into possible mechanisms underlying human hereditary dentin disorders and reparative dentin formation.

  16. Spherical aberration and other higher-order aberrations in the human eye : from summary wave-front analysis data to optical variables relevant to visual perception

    NARCIS (Netherlands)

    Jansonius, Nomdo M.

    2010-01-01

    Wave-front analysis data from the human eye are commonly presented using the aberration coefficient c(4)(0) (primary spherical aberration) together with an overall measure of all higher-order aberrations. If groups of subjects are compared, however, the relevance of an observed difference cannot eas

  17. Aberrant Gene Expression in Acute Myeloid Leukaemia

    DEFF Research Database (Denmark)

    Bagger, Frederik Otzen

    Summary Acute Myeloid Leukaemia (AML) is an aggressive cancer of the bone marrow, affecting formation of blood cells during haematopoiesis. This thesis presents investigation of AML using mRNA gene expression profiles (GEP) of samples extracted from the bone marrow of healthy and diseased subjects...... genes and genetic signatures and for reducing dimensionally of gene expression data. Next, we have used machine-learning methods to predict survival and to assess important predictors based on these results. General application of a number of these methods has been implemented into two public query...

  18. Radiation-induced chromosome aberrations in human lymphocytes

    International Nuclear Information System (INIS)

    Dose-response relationships for unstable chromosome exchange aberrations were obtained after irradiation with 200 kV X-rays and 60Co gamma rays, the doses ranging within 0.05-3.0 Gy. The data points were fitted to the linear quadratic model Y = C + αD + βD2, and after the chromosome hits leading to two-break unstable aberrations were estimated, to the model average x = C +kD. The results fitted the latter model particularly well, the index of determination being 0.988 for gamma rays and 0.997 for X-rays. The RBE of 200 kV X-rays as compared with 60Co gamma radiation was 1.6, when primary chromosome breaks leading to dicentric and centric ring aberrations were used as the biological endpoint. (author)

  19. Correcting the Chromatic Aberration in Barrel Distortion of Endoscopic Images

    Directory of Open Access Journals (Sweden)

    Y. M. Harry Ng

    2003-04-01

    Full Text Available Modern endoscopes offer physicians a wide-angle field of view (FOV for minimally invasive therapies. However, the high level of barrel distortion may prevent accurate perception of image. Fortunately, this kind of distortion may be corrected by digital image processing. In this paper we investigate the chromatic aberrations in the barrel distortion of endoscopic images. In the past, chromatic aberration in endoscopes is corrected by achromatic lenses or active lens control. In contrast, we take a computational approach by modifying the concept of image warping and the existing barrel distortion correction algorithm to tackle the chromatic aberration problem. In addition, an error function for the determination of the level of centroid coincidence is proposed. Simulation and experimental results confirm the effectiveness of our method.

  20. Biological dosimetry: chromosomal aberration analysis for dose assessment

    International Nuclear Information System (INIS)

    In view of the growing importance of chromosomal aberration analysis as a biological dosimeter, the present report provides a concise summary of the scientific background of the subject and a comprehensive source of information at the technical level. After a review of the basic principles of radiation dosimetry and radiation biology basic information on the biology of lymphocytes, the structure of chromosomes and the classification of chromosomal aberrations are presented. This is followed by a presentation of techniques for collecting blood, storing, transporting, culturing, making chromosomal preparations and scaring of aberrations. The physical and statistical parameters involved in dose assessment are discussed and examples of actual dose assessments taken from the scientific literature are given

  1. Split-plot fractional designs: Is minimum aberration enough?

    DEFF Research Database (Denmark)

    Kulahci, Murat; Ramirez, Jose; Tobias, Randy

    2006-01-01

    Split-plot experiments are commonly used in industry for product and process improvement. Recent articles on designing split-plot experiments concentrate on minimum aberration as the design criterion. Minimum aberration has been criticized as a design criterion for completely randomized fractional...... factorial design and alternative criteria, such as the maximum number of clear two-factor interactions, are suggested (Wu and Hamada (2000)). The need for alternatives to minimum aberration is even more acute for split-plot designs. In a standard split-plot design, there are several types of two...... for completely randomized designs. Consequently, we provide a modified version of the maximum number of clear two-factor interactions design criterion to be used for split-plot designs....

  2. On-line correction of aberrations in particle spectrographs

    International Nuclear Information System (INIS)

    A new method is presented that allows the reconstruction of trajectories and the on-line correction of residual aberrations that limit the resolution of particle spectrographs. Using a computed or fitted high order transfer map that describes the uncorrected aberrations of the spectrograph under consideration, it is possible to determine a pseudo transfer map that allows the computation of the corrected data of interest as well as the reconstructed trajectories in terms of position measurements in two planes near the focal plane. The technique is only limited by the accuracy of the position measurements and the accuracy of the transfer map. In practice the method can be expressed as an inversion of a pseudo transfer map and implemented in the differential algebraic framework. The method will be used to correct residual high aberrations in the S800 spectrograph which is under construction at the National Superconducting Cyclotron Laboratory at Michigan State University

  3. Non-Gaussianity and CMB aberration and Doppler

    CERN Document Server

    Catena, Riccardo; Notari, Alessio; Renzi, Alessandro

    2013-01-01

    The peculiar motion of an observer with respect to the CMB rest frame induces a deflection in the arrival direction of the observed photons (also known as CMB aberration) and a Doppler shift in the measured photon frequencies. As a consequence, aberration and Doppler effects induce non trivial correlations between the harmonic coefficients of the observed CMB temperature maps. In this paper we investigate whether these correlations generate a bias on Non-Gaussianity estimators $f_{NL}$. We perform this analysis simulating a large number of temperature maps with Planck-like resolution (lmax $= 2000$) as different realizations of the same cosmological fiducial model (WMAP7yr). We then add to these maps aberration and Doppler effects employing a modified version of the HEALPix code. We finally evaluate a generalization of the Komatsu, Spergel and Wandelt Non-Gaussianity estimator for all the simulated maps, both when peculiar velocity effects have been considered and when these phenomena have been neglected. Usi...

  4. A study on optical aberrations in parabolic neutron guides

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yu; Wang, Hongli; Liu, Yuntao [Neutron Scattering Laboratory, China Institute of Atomic Energy, Beijing 102413 (China); Zu, Yong [China International Engineering Consulting Corporation, Beijing 100048 (China); He, Linfeng; Wei, Guohai; Sun, Kai [Neutron Scattering Laboratory, China Institute of Atomic Energy, Beijing 102413 (China); Han, Songbai, E-mail: hansb@ciae.ac.cn [Neutron Scattering Laboratory, China Institute of Atomic Energy, Beijing 102413 (China); Chen, Dongfeng, E-mail: dongfeng@ciae.ac.cn [Neutron Scattering Laboratory, China Institute of Atomic Energy, Beijing 102413 (China)

    2015-06-21

    It is widely believed that a neutron beam can be focused to a small spot using a parabolic guide, which will significantly improve the flux. However, researchers have also noted challenges for the neutron inhomogeneous phase space distribution in parabolic focusing guide systems. In this paper, the sources of most prominent optical aberrations, such as an inhomogeneous phase space distribution and irregular divergence distribution, are discussed, and an optimization solution is also proposed. We indicate that optimizing the parabolic guide geometrical configuration removes almost all of the aberrations and yields a considerable intensity gain factor.

  5. Aberrations of the point spread function of a multimode fiber

    CERN Document Server

    Descloux, Adrien; Pinkse, Pepijn W H

    2016-01-01

    We investigate the point spread function of a multimode fiber. The distortion of the focal spot created on the fiber output facet is studied for a variety of the parameters. We develop a theoretical model of wavefront shaping through a multimode fiber and use it to confirm our experimental results and analyze the nature of the focal distortions. We show that aberration-free imaging with a large field of view can be achieved by using an appropriate number of segments on the spatial light modulator during the wavefront-shaping procedure. The results describe aberration limits for imaging with multimode fibers as in, e.g., microendoscopy.

  6. Investigation of spherical aberration effects on coherent lidar performance

    DEFF Research Database (Denmark)

    Hu, Qi; Rodrigo, Peter John; Iversen, Theis Faber Quist;

    2013-01-01

    different telescope configurations using a hard target. It is experimentally and numerically proven that the SA has a significant impact on lidar antenna efficiency and optimal beam truncation ratio. Furthermore, we demonstrate that both effective probing range and spatial resolution of the system are......In this paper we demonstrate experimentally the performance of a monostatic coherent lidar system under the influence of phase aberrations, especially the typically predominant spherical aberration (SA). The performance is evaluated by probing the spatial weighting function of the lidar system with...

  7. Double aberration correction in a low-energy electron microscope

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Th., E-mail: schmidtt@fhi-berlin.mpg.de [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 6-8, D-14195 Berlin (Germany); Universitaet Wuerzburg, Experimentelle Physik II, Am Hubland, D-97074 Wuerzburg (Germany); Marchetto, H.; Levesque, P.L. [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 6-8, D-14195 Berlin (Germany); Groh, U.; Maier, F. [Universitaet Wuerzburg, Experimentelle Physik II, Am Hubland, D-97074 Wuerzburg (Germany); Preikszas, D. [Technische Universitaet Darmstadt, Angewandte Physik, Hochschulstrasse 6, D-64289 Darmstadt (Germany); Carl Zeiss NTS GmbH, Carl-Zeiss-Strasse 56, D-73447 Oberkochen (Germany); Hartel, P.; Spehr, R. [Technische Universitaet Darmstadt, Angewandte Physik, Hochschulstrasse 6, D-64289 Darmstadt (Germany); Lilienkamp, G. [Technische Universitaet Clausthal, Physikalisches Institut, Leibnizstrasse 4, D-38678 (Germany); Engel, W. [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 6-8, D-14195 Berlin (Germany); Fink, R. [Universitaet Erlangen-Nuernberg, Physikalische Chemie II, Egerlandstrasse 3, D-91058 Erlangen (Germany); Bauer, E. [Technische Universitaet Clausthal, Physikalisches Institut, Leibnizstrasse 4, D-38678 (Germany); Arizona State University, Department of Physics, Tempe, AZ 85287 (United States); Rose, H. [Technische Universitaet Darmstadt, Angewandte Physik, Hochschulstrasse 6, D-64289 Darmstadt (Germany); Umbach, E. [Universitaet Wuerzburg, Experimentelle Physik II, Am Hubland, D-97074 Wuerzburg (Germany); Freund, H.-J. [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 6-8, D-14195 Berlin (Germany)

    2010-10-15

    The lateral resolution of a surface sensitive low-energy electron microscope (LEEM) has been improved below 4 nm for the first time. This breakthrough has only been possible by simultaneously correcting the unavoidable spherical and chromatic aberrations of the lens system. We present an experimental criterion to quantify the aberration correction and to optimize the electron optical system. The obtained lateral resolution of 2.6 nm in LEEM enables the first surface sensitive, electron microscopic observation of the herringbone reconstruction on the Au(1 1 1) surface.

  8. Analysis of chromosomal aberrations, micronuclei and hematological disorders among workers of wireless communication instruments and cell phone (Mobile) users

    International Nuclear Information System (INIS)

    This study was carried out to investigate the hazardous effect of electromagnetic radiation (EMR) such as chromosomal aberration, disturbed micronucleus formation and hematological disorders that may detected among workers of wireless communication instruments and mobile phone users. Seven individuals ( 3 males and 4 females) of a central workers in the microwave unit of the wireless station and 7 users of Mobil phone (4 males and 3 females ) were volunteered to give blood samples. Chromosomes and micronucleus were prepared for cytogenetic analysis as well as blood film for differential count. The results obtained in the microwave group indicated that, the total summation of all types of aberrations (chromosomes and chromatid aberrations) had a frequency of 6. 14% for the exposed group, whereas, the frequency in the control group amounted to 1.57%. In Mobil phone users, the total summation of all types of aberrations(chromosome and chromatid aberrations) had a frequency of 4.43% for the exposed group and 1.71% for the control group. The incidence of the total number of micronuclei in the exposed microwave group was increased 4.3 folds as compared with those of the control group The incidence of the total number of micronuclei in the exposed mobile phone group was increased 2 fold as compared with those in the control group. On the other hand, normal ranges of total white blood cells counts were determined for mobile phone users but abnormalities in the differential counts of the different types of the white blood cells such as neutropenia, eosinophilia and lymphocytosis were observed in the individuals number 1,2,3,7 in microwave group

  9. Estrogen receptor α or β loss in the colon of Min/+ mice promotes crypt expansion and impairs TGFβ and HNF3β signaling.

    Science.gov (United States)

    Hasson, Rian M; Briggs, Alexandra; Carothers, Adelaide M; Davids, Jennifer S; Wang, Jiping; Javid, Sara H; Cho, Nancy L; Bertagnolli, Monica M

    2014-01-01

    Adenomatous polyposis coli (APC)-regulated Wnt and transforming growth factor-β (TGFβ) signaling cooperate in the intestine to maintain normal enterocyte functions. Human clinical trials showed that estrogen [17β-estradiol (E2)], the ligand of nuclear receptors estrogen receptor α (ERα) and ERβ, inhibited colorectal cancer (CRC) in women. Consistent with this finding, we reported that E2, ERα and ERβ suppressed intestinal tumorigenesis in the C57BL/6J-Min/+ (Min/+) mouse, a CRC model. Here, we extended our results with further comparisons of colon and small intestine from intact female Apc (+/+) (WT), Min/+ and ER-deficient Min/+ mice. In the colon of ER-deficient Min/+ mice, ER loss reduced TGFβ signaling in crypt base cells as evidenced by minimal expression of the effectors Smad 2, 3 and 4 in these strains. We also found reduced expression of Indian hedgehog (Ihh), bone morphogenetic protein 4 and hepatocyte nuclear factor 3β or FoxA2, factors needed for paracrine signaling between enterocytes and mesenchyme. In proximal colon, ER loss produced a >10-fold increased incidence of crypt fission, a marker for wound healing and tumor promotion. These data, combined with our previous work detailing the specific roles of E2, ERα and ERβ in the colon, suggest that ER activity helps to maintain the intestinal stem cell (ISC) microenvironment by modulating epithelial-stromal crosstalk in ways that regulate cytokine, Wnt and Ihh availability in the extracellular matrix (ECM). PMID:24104551

  10. Effect of Coma Aberration on Orbital Angular Momentum Spectrum of Vortex Beams

    Institute of Scientific and Technical Information of China (English)

    CHEN Zi-Yang; PU Ji-Xiong

    2009-01-01

    Spiral spectra of vortex beams with coma aberration are studied.It is shown that the orbital angular momentum (OAM) states of vortex beams with coma aberration are different from those aberration-free vortex beams.Spiral spectra of beams with coma aberration are spreading.It is found that in the presence of coma aberration,the vortex beams contain not only the original OAM component but also other components.A larger coma aberration coefficient and/or a larger beam waist will lead to a wider spreading of the spiral spectrum. The results may have potential applications in information encoding and transmittance.

  11. Aberration of a negative ion beam caused by space charge effect

    International Nuclear Information System (INIS)

    Aberrations are inevitable when the charged particle beams are extracted, accelerated, transmitted, and focused with electrostatic and magnetic fields. In this study, we investigate the aberration of a negative ion accelerator for a neutral beam injector theoretically, especially the spherical aberration caused by the negative ion beam expansion due to the space charge effect. The negative ion current density profiles with the spherical aberration are compared with those without the spherical aberration. It is found that the negative ion current density profiles in a log scale are tailed due to the spherical aberration.

  12. Study of chromosome aberration repair after acute or fractionated X-irradiation in human peripheral lymphocytes

    International Nuclear Information System (INIS)

    Pure human peripheral blood has been subjected to a single irradiation with the dose of 125 and 250R and by fractions with the doses of 125+125 R in the following periods of the cell cycle: 0, 2, 4, 6, 8, 12, 16, 24, 30, 40 and 45 hrs. The following types of structural chromosome aberrations are counted on metaphase plates with a good chromosome scattering: dicentrics, rings, interstitial deletions, symmetric translocations, chromatide and chromosome fragments. The data on polycentrics and rings prove to be most characteristic: the frequency of these aberrations in the case of single irradiation for all periods of the ''presynthetic'' Gsub(I) period is stable varying in the range of 17-20% in the case of a 125 R dose and 66-73% in the case of a 250 R dose. Their frequency decreased for both doses of irradiation in later periods and reached 1% by the end of the synthetic period. The fractionated effect of two doses 125 R each gives the following values of polycentric and ring formation: second hour - 44,15%, fourth - 50,82%, sixth - 55,15% eighth -58,32% (maximum), twelfth - 55,48%. The descending tendency is preserved till the end of the presynthetic period and in the synthetic period. The statistic processing of results shows statistically authentic differences between fractionated and single irradiation in the output of polycentrics and rings, as well as other types of aberrations and breaks per cell. The data obtained permit to conclude that repair processes are undulatory and are characterized by maximum intensity in the first hours of presynthetic period which weakens to the 8th hour and then strengthens again almost to the end of the synthetic period

  13. Frequency and distribution studies of asymmetrical versus symmetrical chromosome aberrations

    International Nuclear Information System (INIS)

    Two aspects of the relationship between Asymmetrical (A) and Symmetrical (S) radiation-induced chromosomal aberrations are considered in this paper. (1) Are A and S truly alternative modes of lesion interaction. Relative frequencies for chromatid-type and chromosome-type are examined, and new lymphocyte data using banding is used to look at this, and also for parallelism in chromosome participation of the two forms for various aberration categories. All the tests applied suggest that A and S are alternative interaction modes. (2) The long-term survival characteristics of A and S are discussed, and the differences in expected frequencies of derived S per surviving cell from chromosome-type and chromatid-types are stressed. Since many in vivo tissues have varying mixtures of potential chromatid and chromosome aberration-bearing target cells, ultimate cell survival and derived S frequencies may differ between tissues for the same absorbed dose. An Appendix gives Relative Corrected Lengths (RCL) for chromosomes of the human karyotype which should be used when testing the various exchange aberration categories for random chromosome participation. (orig.)

  14. High-Resolution Transmission Electron Microscopy Using Negative Spherical Aberration

    Science.gov (United States)

    Jia, Chun-Lin; Lentzen, Markus

    2004-04-01

    A novel imaging mode for high-resolution transmission electron microscopy is described. It is based on the adjustment of a negative value of the spherical aberration CS of the objective lens of a transmission electron microscope equipped with a multipole aberration corrector system. Negative spherical aberration applied together with an overfocus yields high-resolution images with bright-atom contrast. Compared to all kinds of images taken in conventional transmission electron microscopes, where the then unavoidable positive spherical aberration is combined with an underfocus, the contrast is dramatically increased. This effect can only be understood on the basis of a full nonlinear imaging theory. Calculations show that the nonlinear contrast contributions diminish the image contrast relative to the linear image for a positive-CS setting whereas they reinforce the image contrast relative to the linear image for a negative-CS setting. The application of the new mode to the imaging of oxygen in SrTiO3 and YBa2Cu3O7 demonstrates the benefit to materials science investigations. It allows us to image directly, without further image processing, strongly scattering heavy-atom columns together with weakly scattering light-atom columns.

  15. Polarization aberrations of radiation at the lens focus

    NARCIS (Netherlands)

    Sokolov, AL

    2005-01-01

    The polarization aberrations of radiation at the lens focus are calculated with allowance for diffraction effects. Calculations are performed using the representation of radiation as a coherent set of Hermite-Gauss modes with certain amplitudes, phases, and polarizations. An expression for the longi

  16. Consequences of Aberrant Hedgehog Signaling During Zebrafish Development

    NARCIS (Netherlands)

    Koudijs, M.J.

    2007-01-01

    The Hedgehog signaling pathway is controlling proliferation, patterning and differentiation during development of vertebrates and invertebrates. Aberrant Hedgehog activity has been shown to be one of the underlying causes of a number of congenital disorders and multiple types of cancer. We investiga

  17. The Aberrant Salience Inventory: A New Measure of Psychosis Proneness

    Science.gov (United States)

    Cicero, David C.; Kerns, John G.; McCarthy, Denis M.

    2010-01-01

    Aberrant salience is the unusual or incorrect assignment of salience, significance, or importance to otherwise innocuous stimuli and has been hypothesized to be important for psychosis and psychotic disorders such as schizophrenia. Despite the importance of this concept in psychosis research, no questionnaire measures are available to assess…

  18. Frequency of primary amenorrhea due to chromosomal aberration

    International Nuclear Information System (INIS)

    Objective: To find out the frequency of primary amenorrhea due to chromosomal aberration and the different options available for management. Subjects and Methods: All patients with primary amenorrhea due to chromosomal aberrations were included in study. Patient's detailed history, general physical examination, presence or absence of secondary sexual characteristics, abdominal and pelvic examination finding were noted. Targeted investigations, including ultrasound, hormonal assay, buccal smear and karyotyping results were recorded. The management options were individually tailored with focus n psychological management. Results: Eighteen patients out of 30,000 patients were diagnosed as having primary amenorrhea. Six had primary amenorrhea due to chromosomal aberrations with the frequency of 0.02%. The age at presentation was 20 years and above in 50%. The most common cause was Turner's syndrome seen in 4 out of 6. The presenting symptoms were delay in onset of menstruation in 05 patients and primary infertility in 01 patient. Conclusion: Primary amenorrhea due to chromosomal aberration is an uncommon condition requiring an early and accurate diagnosis. Turner's syndrome is a relatively common cause of this condition. Management should be multi-disciplinary and individualized according to the patient's age and symptom at presentation. Psychological management is very important and counselling throughout treatment is recommended. (author)

  19. Chromatin structure and ionizing-radiation-induced chromosome aberrations

    International Nuclear Information System (INIS)

    The possible influence of chromatic structure or activity on chromosomal radiosensitivity was studied. A cell line was isolated which contained some 105 copies of an amplified plasmid in a single large mosquito artificial chromosome (MAC). This chromosome was hypersensitive to DNase I. Its radiosensitivity was some three fold greater than normal mosquito chromosomes in the same cell. In cultured human cells irradiated during G0, the initial breakage frequency in chromosome 4, 19 and the euchromatic and heterochromatic portions of the Y chromosome were measured over a wide range of doses by inducing Premature Chromosome Condensation (PCC) immediately after irradiation with Cs-137 gamma rays. No evidence was seen that Y heterochromatin or large fragments of it remained unbroken. The only significant deviation from the expected initial breakage frequency per Gy per unit length of chromosome was that observed for the euchromatic portion of the Y chromosome, with breakage nearly twice that expected. The development of aberrations involving X and Y chromosomes at the first mitosis after irradation was also studied. Normal female cells sustained about twice the frequency of aberrations involving X chromosomes for a dose of 7.3 Gy than the corresponding male cells. Fibroblasts from individuals with supernumerary X chromosomes did not show any further increase in X aberrations for this dos. The frequency of aberrations involving the heterochromatic portion of the long arm of the Y chromosome was about what would be expected for a similar length of autosome, but the euchromatic portion of the Y was about 3 times more radiosensitive per unit length. 5-Azacytidine treatment of cultured human female fibroblasts or fibroblasts from a 49,XXXXY individual, reduced the methylation of cytosine residues in DNA, and resulted in an increased chromosomal radiosensitivity in general, but it did not increase the frequency of aberrations involving the X chromosomes

  20. Subjective face recognition difficulties, aberrant sensibility, sleeping disturbances and aberrant eating habits in families with Asperger syndrome

    Directory of Open Access Journals (Sweden)

    Källman Tiia

    2005-04-01

    Full Text Available Abstract Background The present study was undertaken in order to determine whether a set of clinical features, which are not included in the DSM-IV or ICD-10 for Asperger Syndrome (AS, are associated with AS in particular or whether they are merely a familial trait that is not related to the diagnosis. Methods Ten large families, a total of 138 persons, of whom 58 individuals fulfilled the diagnostic criteria for AS and another 56 did not to fulfill these criteria, were studied using a structured interview focusing on the possible presence of face recognition difficulties, aberrant sensibility and eating habits and sleeping disturbances. Results The prevalence for face recognition difficulties was 46.6% in individuals with AS compared with 10.7% in the control group. The corresponding figures for subjectively reported presence of aberrant sensibilities were 91.4% and 46.6%, for sleeping disturbances 48.3% and 23.2% and for aberrant eating habits 60.3% and 14.3%, respectively. Conclusion An aberrant processing of sensory information appears to be a common feature in AS. The impact of these and other clinical features that are not incorporated in the ICD-10 and DSM-IV on our understanding of AS may hitherto have been underestimated. These associated clinical traits may well be reflected by the behavioural characteristics of these individuals.

  1. Genotoxicity evaluation of dental restoration nanocomposite using comet assay and chromosome aberration test

    International Nuclear Information System (INIS)

    Nanocomposite is used as a dental filling to restore the affected tooth, especially in dental caries. The dental nanocomposite (KelFil) for tooth restoration used in this study was produced by the School of Dental Sciences, Universiti Sains Malaysia, Malaysia and is incorporated with monodispersed, spherical nanosilica fillers. The aim of the study was to determine the genotoxic effect of KelFil using in vitro genotoxicity tests. The cytotoxicity and genotoxicity of KelFil was evaluated using MTT assay, comet assay and chromosome aberration tests with or without the addition of a metabolic activation system (S9 mix), using the human lung fibroblast cell line (MRC-5). Concurrent negative and positive controls were included. In the comet assay, no comet formation was found in the KelFil groups. There was a significant difference in tail moment between KelFil groups and positive control (p < 0.05). Similarly, no significant aberrations in chromosomes were noticed in KelFil groups. The mitotic indices of treatment groups and negative control were significantly different from positive controls. Hence, it can be concluded that the locally produced dental restoration nanocomposite (KelFil) is non-genotoxic under the present test conditions. (paper)

  2. Numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana

    NARCIS (Netherlands)

    Ji, X.

    2014-01-01

    Numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana. I studied numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana. The large genomic changes are important for

  3. Aberrations measurement of freeform spectacle lenses based on Hartmann wavefront technology.

    Science.gov (United States)

    Yu, Jing; Fang, Fengzhou; Qiu, Zhongjun

    2015-02-10

    Freeform spectacle lenses have been popularized in the past few years. Traditional evaluation methods only focused on the refractive power parameters. The inspection technology of wavefront aberration has been introduced to optometry. In this paper, the wavefront aberration is used to evaluate the freeform spectacle lenses. The Shack-Hartmann wavefront technology is used to measure the same zones on the lenses with different designed forms. It shows that the aberration distributions are different from each other. The design with the freeform surface on the back can obtain the smallest aberrations in the entire surface. The aberrations on different zones for the same lens are analyzed. The blending zones show the greatest aberrations. The aberration on the progressive corridor is greater than the other zones. The Hartmann wavefront technology can be used to measure the wavefront aberration of freeform spectacle lenses. PMID:25968012

  4. Chromosomal Aberrations in DNA Repair Defective Cell Lines: Comparisons of Dose Rate and Radiation Quality

    Science.gov (United States)

    George, K. A.; Hada, M.; Patel, Z.; Huff, J.; Pluth, J. M.; Cucinotta, F. A.

    2009-01-01

    Chromosome aberration yields were assessed in DNA double-strand break repair (DSB) deficient cells after acute doses of gamma-rays or high-LET iron nuclei, or low dose-rate (0.018 Gy/hr) gamma-rays. We studied several cell lines including fibroblasts deficient in ATM (product of the gene that is mutated in ataxia telangiectasia patients) or NBS (product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase, DNA-PK activity. Chromosomes were analyzed using the fluorescence in-situ hybridization (FISH) chromosome painting method in cells at the first division post-irradiation and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving >2 breaks in 2 or more chromosomes). Gamma radiation induced higher yields of both simple and complex exchanges in the DSB repair defective cells than in the normal cells. The quadratic dose-response terms for both chromosome exchange types were significantly higher for the ATM and NBS defective lines than for normal fibroblasts. However, the linear dose-response term was significantly higher only for simple exchanges in the NBS cells. Large increases in the quadratic dose response terms indicate the important roles of ATM and NBS in chromatin modifications that facilitate correct DSB repair and minimize aberration formation. Differences in the response of AT and NBS deficient cells at lower doses suggests important questions about the applicability of observations of radiation sensitivity at high dose to low dose exposures. For all iron nuclei irradiated cells, regression models preferred purely linear and quadratic dose responses for simple and complex exchanges, respectively. All the DNA repair defective cell lines had lower Relative biological effectiveness (RBE) values than normal cells, the lowest being for the DNA-PK-deficient cells, which was near unity. To further

  5. The environmental monitoring of Cultural Heritage through Low Cost strategies: The frescoes of the crypt of St. Francesco d'Assisi's, Irsina (Basilicata, Southern Italy)

    Science.gov (United States)

    Sileo, Maria; Gizzi, Fabrizio; Masini, Nicola

    2015-04-01

    One of the main tools of assessment and diagnosis used to define appropriate strategies for the preservation of cultural heritage is the environmental monitoring. To achieve an environmental monitoring are needed high costs of purchase and maintenance, high costs of instrumental and for the management of the plants and processing of results. These costs imply that the technologies for environmental monitoring are not as common but their use is limited to the study very famous monuments or sites. To extend the use and dissemination of such technologies to a greater number of monuments, through the project Pro_Cult (Advanced methodological approaches and technologies for Protection and Security of Cultural Heritage) a research aimed at testing low cost technologies has been performed. The aim of the research is to develop low cost monitoring systems, assessing their effectiveness in a comparative way with commercial high cost ones. To this aim an environmental monitoring system using the Arduino system was designed and developed. It is an electronics prototyping platform based on open-source hardware and software flexible and user friendly. This system is connected to sensors for the detection of environmental parameters of non high purchase cost but with respect to the medium potential detection sensors accurately. This low cost system was tested in the framework of a microclimate monitoring project of the crypt of St. Francis of Assisi in Irsina (Southern Italy) enriched by a precious cycle of medieval frescoes. The aim of this research was to compare two monitoring systems, the first, at low cost, using Arduino system, and the second, a standard commercial product for a full yearly cycle and assess the reliability and the results obtained by the two systems. This paper shows the results of the comparative analysis of an entire monitoring yearly cycle in relation to the problems of degradation affecting the paintings of medieval crypt [1]. The obtained results

  6. A Case Study of the Reduction of Aberrant, Repetitive Responses of an Adolescent with Autism.

    Science.gov (United States)

    Gunter, Philip L.; And Others

    1993-01-01

    In this case study, music was applied noncontingently and contingently across four settings with an adolescent male with autism, to reduce aberrant, repetitive vocalizations. The intervention was associated with dramatic reductions in the primary aberrant behavior and reductions in two other aberrant behaviors. Task performance was differentially…

  7. Studies on chromosome aberrations in workers occupationally exposed to radiation

    International Nuclear Information System (INIS)

    Cytogenetic assays for unstable chromosomes were performed on 54 medical radiation workers who are occupationally exposed to radiation and 42 controls. A total of 15,577 metaphase cells were scored. The frequencies of dicentrics and acentric chromosomes on controls were 0.52*10-3 and 0.82*10-2, respectively. On radiation workers those were 2.28*10-3 and 1.34*10-2, respectively. Though the frequencies of all types of chromosome aberrations in the workers were higher than those in the controls, the only significant difference was found in the case of dicentrics (P 0.05) except exposure dose of recent one year (P < 0.05). These results could indicate that low level exposure to ionizing radiation can induce unstable chromosome aberrations in blood lymphocytes

  8. [239Pu and chromosomal aberrations in human peripheral blood lymphocytes].

    Science.gov (United States)

    Okladnikova, N D; Osovets, S V; Kudriavtseva, T I

    2009-01-01

    The genome status in somatic cells was assessed using the chromosomal aberration (CA) test in peripheral blood lymphocytes from 194 plutonium workers exposed to occupational radiation mainly from low-transportable compounds of airborne 230Pu. Pu body burden at the time of cytogenetic study varied from values close to the method sensitivity to values multiply exceeding the permissible level. Standard (routine) methods of peripheral blood lymphocytes cultivation were applied. Chromatid- and chromosomal-type structural changes were estimated. Aberrations were estimated per 100 examined metaphase cells. The quantitative relationship between the CA frequency and Pu body burden and the absorbed dose to the lung was found. Mathematical processing of results was carried out based on the phenomenological model. The results were shown as theoretical and experimental curves. The threshold of the CA yield was 0.43 +/- 0.03 kBq (Pu body burden) and 6.12 +/- 1.20 cGy (absorbed dose to the lung).

  9. Mathematical Modeling of Carcinogenesis Based on Chromosome Aberration Data

    Institute of Scientific and Technical Information of China (English)

    Xiao-bo Li

    2009-01-01

    Objective: The progression of human cancer is characterized by the accumulation of genetic instability. An increasing number of experimental genetic molecular techniques have been used to detect chromosome aberrations. Previous studies on chromosome abnormalities often focused on identifying the frequent loci of chromosome alterations, but rarely addressed the issue of interrelationship of chromosomal abnormalities. In the last few years, several mathematical models have been employed to construct models of carcinogenesis, in an attempt to identify the time order and cause-and-effect relationship of chromosome aberrations. The principles and applications of these models are reviewed and compared in this paper. Mathematical modeling of carcinogenesis can contribute to our understanding of the molecular genetics of tumor development, and identification of cancer related genes, thus leading to improved clinical practice of cancer.

  10. Correction of Optical Aberrations in Elliptic Neutron Guides

    CERN Document Server

    Bentley, Phillip M; Andersen, Ken H; Rodriguez, Damian Martin; Mildner, David F R

    2012-01-01

    Modern, nonlinear ballistic neutron guides are an attractive concept in neutron beam delivery and instrumentation, because they offer increased performance over straight or linearly tapered guides. However, like other ballistic geometries they have the potential to create significantly non-trivial instrumental resolution functions. We address the source of the most prominent optical aberration, namely coma, and we show that for extended sources the off-axis rays have a different focal length from on-axis rays, leading to multiple reflections in the guide system. We illustrate how the interplay between coma, sources of finite size, and mirrors with non-perfect reflectivity can therefore conspire to produce uneven distributions in the neutron beam divergence, the source of complicated resolution functions. To solve these problems, we propose a hybrid elliptic-parabolic guide geometry. Using this new kind of neutron guide shape, it is possible to condition the neutron beam and remove almost all of the aberration...

  11. Detection of epigenetic aberrations in the development of hepatocellular carcinoma.

    Science.gov (United States)

    Zhang, Yujing

    2015-01-01

    Hepatocellular carcinoma (HCC) is the third most common cause of cancer death worldwide. Hepatocarcinogenesis is a complex, multistep process. It is now recognized that HCC is a both genetic and epigenetic disease; genetic and epigenetic components cooperate at all stages of hepatocarcinogenesis. Epigenetic changes involve aberrant DNA methylation, posttranslational histone modifications and aberrant expression of microRNAs all of which can affect the expression of oncogenes, tumor suppressor genes and other tumor-related genes and alter the pathways in cancer development. Several risk factors for HCC, including hepatitis B and C virus infections and exposure to the chemical carcinogen aflatoxin B1 have been found to influence epigenetic changes. Their interactions could play an important role in the initiation and progression of HCC. Discovery and detection of biomarkers for epigenetic changes is a promising area for early diagnosis and risk prediction of HCC.

  12. Chromosomal Aberrations in Humans Induced by Urban Air Pollution

    DEFF Research Database (Denmark)

    Knudsen, Lisbeth E.; Norppa, Hannu; Gamborg, Michael O.;

    1999-01-01

    We have studied the influence of individual susceptibility factors on the genotoxic effects of urban air pollution in 106 nonsmoking bus drivers and 101 postal workers in the Copenhagen metropolitan area. We used the frequency of chromosomal aberrations in peripheral blood lymphocytes...... that long-term exposure to urban air pollution (with traffic as the main contributor) induces chromosome damage in human somatic cells. Low DNA repair capacity and GSTM1 and NAT2 variants associated with reduced detoxification ability increase susceptibility to such damage. The effect of the GSTM1 genotype......, which was observed only in the bus drivers, appears to be associated with air pollution, whereas the NAT2 genotype effect, which affected all subjects, may influence the individual response to some other common exposure or the baseline level of chromosomal aberrations....

  13. Aberrant Phenotype in Iranian Patients with Acute Myeloid Leukemia

    Directory of Open Access Journals (Sweden)

    Mehdi Jahedi

    2014-03-01

    Full Text Available Purpose: The aim of this study was to evaluate the incidence of aberrant phenotypes and possible prognostic value in peripheral and bone marrow blood mononuclear cells of Iranian patients with AML. Methods: 56 cases of de novo AML (2010-2012 diagnosed by using an acute panel of monoclonal antibodies by multiparametric flowcytometry. Immunophenotyping was done on fresh bone marrow aspirate and/or peripheral blood samples using the acute panel of MoAbs is stained with Phycoerythrin (PE /fluorescein isothiocyanate (FITC, Allophycocyanin (APC and Peridinin-chlorophyll protein complex (perCP. We investigated Co-expression of lymphoid-associated markers CD2, CD3, CD7, CD 10, CD19, CD20 and CD22 in myeloblasts. Results: Out of the 56 cases, 32 (57.1% showed AP. CD7 was positive in 72.7% of cases in M1 and 28.5% in M2 but M3 and M4 cases lacked this marker. We detected CD2 in 58.35 of M1cases, 21.40% of M2 cases, 33.3 of M3 and 20% of M5; but M4 patients lacked this marker. The CBC analysis demonstrated a wide range of haemoglobin concentration, Platelet and WBC count which varied from normal to anaemia, thrombocytopenia to thrombocytosis and leukopenia to hyper leukocytosis. Conclusions: Our findings showed that CD7 and CD2 were the most common aberrant marker in Iranian patients with AML. However, we are not find any significant correlation between aberrant phenotype changing and MRD in our population. Taken together, this findings help to provide new insights in to the investigation of other aberrant phenotypes that may play roles in diagnosis and therapeutic of AML.

  14. An integrative characterization of recurrent molecular aberrations in glioblastoma genomes

    OpenAIRE

    Sintupisut, Nardnisa; Liu, Pei-Ling; Yeang, Chen-Hsiang

    2013-01-01

    Glioblastoma multiforme (GBM) is the most common and malignant primary brain tumor in adults. Decades of investigations and the recent effort of the Cancer Genome Atlas (TCGA) project have mapped many molecular alterations in GBM cells. Alterations on DNAs may dysregulate gene expressions and drive malignancy of tumors. It is thus important to uncover causal and statistical dependency between ‘effector’ molecular aberrations and ‘target’ gene expressions in GBMs. A rich collection of prior st...

  15. Aberrant functional brain connectome in people with antisocial personality disorder

    OpenAIRE

    Yan Tang; Jun Long; Wei Wang(College of William and Mary); Jian Liao; Hua Xie; Guihu Zhao; Hao Zhang

    2016-01-01

    Antisocial personality disorder (ASPD) is characterised by a disregard for social obligations and callous unconcern for the feelings of others. Studies have demonstrated that ASPD is associated with abnormalities in brain regions and aberrant functional connectivity. In this paper, topological organisation was examined in resting-state fMRI data obtained from 32 ASPD patients and 32 non-ASPD controls. The frequency-dependent functional networks were constructed using wavelet-based correlation...

  16. Evaluation of corneal higher order aberrations in normal topographic patterns

    OpenAIRE

    Mirzajani, Ali; Aghataheri, Sattar; Ghoreishi, Mohammad; Jafarzadepour, Ebrahim; Mohammadinia, Mohadese

    2016-01-01

    Purpose This study reports the characteristics of corneal higher order aberrations (HOAs) in eyes with normal topographic pattern using the Pentacam scheimpflug system. Methods In this prospective, observational, comparative study, 165 eyes of 97 patients separated into five groups based on corneal topographic patterns were enrolled. All eyes received a comprehensive ophthalmologic examination including corneal tomographic analysis with the Pentacam system. Keratometry, corneal cylinder, and ...

  17. Aberrant left pulmonary artery associated with right pulmonary hypoplasia

    International Nuclear Information System (INIS)

    Aberrant left pulmonary artery (ALPA), or pulmonary artery sling, is an uncommon vascular malformation that is frequently associated with obstructive disorders of the tracheobronquial tree. In newborns, it produces severe respiratory problems. In contrast, in adults, it is usually discovered by change. ALPA has been associated with right pulmonary hypoplasia (RPH) in a small number of cases. We present a new case of ALP associated with right pulmonary hypoplasia in an adult woman, diagnosed by CT and MR. 12 refs

  18. Use of chromosome aberrations for predicting genetic hazards to man

    International Nuclear Information System (INIS)

    The question of the use of chromosome aberrations for predicting genetic hazards to man is discussed under the following headings: interspecific comparisons of dicentric and deletion production in peripheral leukocytes; comparison of dicentric yields in leukocytes to reciprocal translocation yield in spermatogonia; recovery of spermatogonia induced translocations in the sons of irradiated males; cytologically and genetically detected deletions; and current gaps in our knowledge and problems of future interest

  19. Chromosome aberrations and environmental exposures in acute leukemia

    OpenAIRE

    Lindquist, Ragnhild Rosengren

    2009-01-01

    The aims of this thesis are to evaluate the role of environmental exposures, especially professional exposure to organic solvents and petroleum products in the etiology of acute leukemia and to investigate if there is a correlation between the exposure to a specific leukemogen factor and a clonal chromosome aberration of the leukemic cells. Papers I and II present results of a case-control study of environmental exposures, in all occupations during life-time, medical treatm...

  20. Aberrant Gene Promoter Methylation Associated with Sporadic Multiple Colorectal Cancer

    OpenAIRE

    Victoria Gonzalo; Juan José Lozano; Jenifer Muñoz; Francesc Balaguer; Maria Pellisé; Cristina Rodríguez de Miguel; Montserrat Andreu; Rodrigo Jover; Xavier Llor; M Dolores Giráldez; Teresa Ocaña; Anna Serradesanferm; Virginia Alonso-Espinaco; Mireya Jimeno; Miriam Cuatrecasas

    2010-01-01

    BACKGROUND: Colorectal cancer (CRC) multiplicity has been mainly related to polyposis and non-polyposis hereditary syndromes. In sporadic CRC, aberrant gene promoter methylation has been shown to play a key role in carcinogenesis, although little is known about its involvement in multiplicity. To assess the effect of methylation in tumor multiplicity in sporadic CRC, hypermethylation of key tumor suppressor genes was evaluated in patients with both multiple and solitary tumors, as a proof-of-...

  1. Analysis of Chromosomal Aberrations after Low and High Dose Rate Gamma Irradiation in ATM or NBS Suppressed Human Fibroblast Cells

    Science.gov (United States)

    Hada, M.; Huff, J. L.; Patel, Z.; Pluth, J. M.; George, K. A.; Cucinotta, F. A.

    2009-01-01

    A detailed understanding of the biological effects of heavy nuclei is needed for space radiation protection and for cancer therapy. High-LET radiation produces more complex DNA lesions that may be non-repairable or that may require additional processing steps compared to endogenous DSBs, increasing the possibility of misrepair. Interplay between radiation sensitivity, dose, and radiation quality has not been studied extensively. Previously we studied chromosome aberrations induced by low- and high- LET radiation in several cell lines deficient in ATM (ataxia telangactasia mutated; product of the gene that is mutated in ataxia telangiectasia patients) or NBS (nibrin; product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase (DNA-PK) activity. We found that the yields of both simple and complex chromosomal aberrations were significantly increased in the DSB repair defective cells compared to normal cells. The increased aberrations observed for the ATM and NBS defective lines was due to a significantly larger quadratic dose-response term compared to normal fibroblasts for both simple and complex aberrations, while the linear dose-response term was significantly higher in NBS cells only for simple exchanges. These results point to the importance of the functions of ATM and NBS in chromatin modifications that function to facilitate correct DSB repair and minimize aberration formation. To further understand the sensitivity differences that were observed in ATM and NBS deficient cells, in this study, chromosomal aberration analysis was performed in normal lung fibroblast cells treated with KU-55933, a specific ATM kinase inhibitor, or Mirin, an MRN complex inhibitor involved in activation of ATM. We are also testing siRNA knockdown of these proteins. Normal and ATM or NBS suppressed cells were irradiated with gamma-rays and chromosomes were collected with a premature chromosome

  2. Dynamics of multiple bubbles, excited by femtosecond filament in water: Role of aberrations

    CERN Document Server

    Potemkin, F V

    2014-01-01

    Using shadow photography, we observed microsecond time scale evolution of multiple cavitation bubbles, excited by tighty focused femtosecond laser pulse in water under supercritical power regime (~100 Pcr). In these extreme conditions high energy delivery into the microvolume of liquid sample leads to creation of single filament which becomes a source of cavitation region formation. When aberrations were added to the optical scheme the hot spots along the filament axis are formed. At high energies (more than 40uJ) filaments in these hot spots are fired and, as a result, complex pattern of cavitation bubbles is created. The bubbles can be isolated from each other or build exotic drop-shaped cavitation region, which evolution at the end of its life, before the final collapse, contains the jet emission. The dynamics of the cavitation pattern was investigated from pulse energy and focusing. We found that greater numerical aperture of the focusing optics leads to greater cavitation area length. The strong interact...

  3. Structural alteration of tight and adherens junctions in villous and crypt epithelium of the small and large intestine of conventional nursing piglets infected with porcine epidemic diarrhea virus.

    Science.gov (United States)

    Jung, Kwonil; Eyerly, Bryan; Annamalai, Thavamathi; Lu, Zhongyan; Saif, Linda J

    2015-06-12

    Integrity of the intestinal epithelium is critical for proper functioning of the barrier that regulates absorption of water and restricts uptake of luminal bacteria. It is maintained mainly by tight junctions (TJs) and adherens junctions (AJs). We conducted immunofluorescence (IF) staining for in situ identification of zonula occludin (ZO)-1 proteins for TJ and E-Cadherin proteins for AJ in the small and large intestinal villous and crypt epithelium of nursing pigs infected with porcine epidemic diarrhea virus (PEDV). Twenty 9-day-old piglets [PEDV-infected (n=9) and Mock (n=11)] from PEDV seronegative sows, were orally inoculated [8.9 log₁₀ genomic equivalents/pig] with PEDV PC21A strain or mock. At post-inoculation days (PIDs) 1-5, infected pigs showed severe watery diarrhea and/or vomiting and severe atrophic enteritis. By immunohistochemistry, PEDV antigens were evident in enterocytes lining the villous epithelium. At PIDs 1-5, PEDV-infected pigs exhibited mildly to extensively disorganized, irregular distribution and reduced expression of ZO-1 or E-Cadherin in villous, but not crypt epithelial cells of the jejunum and ileum, but not in the large intestine, when compared to the negative controls. The structural destruction and disorganization of TJ and AJ were extensive in PEDV-infected pigs at PIDs 1-3, but then appeared to reversibly recover at PID 5, as evident by increased numbers of ZO-1-positive epithelial cells and markedly improved appearance of E-Cadherin-positive villous epithelium. Our results suggest a possible involvement of structurally impaired TJ and AJ in the pathogenesis of PEDV, potentially leading to secondary bacterial infections.

  4. Pancreatic cancer genomes reveal aberrations in axon guidance pathway genes.

    Science.gov (United States)

    Biankin, Andrew V; Waddell, Nicola; Kassahn, Karin S; Gingras, Marie-Claude; Muthuswamy, Lakshmi B; Johns, Amber L; Miller, David K; Wilson, Peter J; Patch, Ann-Marie; Wu, Jianmin; Chang, David K; Cowley, Mark J; Gardiner, Brooke B; Song, Sarah; Harliwong, Ivon; Idrisoglu, Senel; Nourse, Craig; Nourbakhsh, Ehsan; Manning, Suzanne; Wani, Shivangi; Gongora, Milena; Pajic, Marina; Scarlett, Christopher J; Gill, Anthony J; Pinho, Andreia V; Rooman, Ilse; Anderson, Matthew; Holmes, Oliver; Leonard, Conrad; Taylor, Darrin; Wood, Scott; Xu, Qinying; Nones, Katia; Fink, J Lynn; Christ, Angelika; Bruxner, Tim; Cloonan, Nicole; Kolle, Gabriel; Newell, Felicity; Pinese, Mark; Mead, R Scott; Humphris, Jeremy L; Kaplan, Warren; Jones, Marc D; Colvin, Emily K; Nagrial, Adnan M; Humphrey, Emily S; Chou, Angela; Chin, Venessa T; Chantrill, Lorraine A; Mawson, Amanda; Samra, Jaswinder S; Kench, James G; Lovell, Jessica A; Daly, Roger J; Merrett, Neil D; Toon, Christopher; Epari, Krishna; Nguyen, Nam Q; Barbour, Andrew; Zeps, Nikolajs; Kakkar, Nipun; Zhao, Fengmei; Wu, Yuan Qing; Wang, Min; Muzny, Donna M; Fisher, William E; Brunicardi, F Charles; Hodges, Sally E; Reid, Jeffrey G; Drummond, Jennifer; Chang, Kyle; Han, Yi; Lewis, Lora R; Dinh, Huyen; Buhay, Christian J; Beck, Timothy; Timms, Lee; Sam, Michelle; Begley, Kimberly; Brown, Andrew; Pai, Deepa; Panchal, Ami; Buchner, Nicholas; De Borja, Richard; Denroche, Robert E; Yung, Christina K; Serra, Stefano; Onetto, Nicole; Mukhopadhyay, Debabrata; Tsao, Ming-Sound; Shaw, Patricia A; Petersen, Gloria M; Gallinger, Steven; Hruban, Ralph H; Maitra, Anirban; Iacobuzio-Donahue, Christine A; Schulick, Richard D; Wolfgang, Christopher L; Morgan, Richard A; Lawlor, Rita T; Capelli, Paola; Corbo, Vincenzo; Scardoni, Maria; Tortora, Giampaolo; Tempero, Margaret A; Mann, Karen M; Jenkins, Nancy A; Perez-Mancera, Pedro A; Adams, David J; Largaespada, David A; Wessels, Lodewyk F A; Rust, Alistair G; Stein, Lincoln D; Tuveson, David A; Copeland, Neal G; Musgrove, Elizabeth A; Scarpa, Aldo; Eshleman, James R; Hudson, Thomas J; Sutherland, Robert L; Wheeler, David A; Pearson, John V; McPherson, John D; Gibbs, Richard A; Grimmond, Sean M

    2012-11-15

    Pancreatic cancer is a highly lethal malignancy with few effective therapies. We performed exome sequencing and copy number analysis to define genomic aberrations in a prospectively accrued clinical cohort (n = 142) of early (stage I and II) sporadic pancreatic ductal adenocarcinoma. Detailed analysis of 99 informative tumours identified substantial heterogeneity with 2,016 non-silent mutations and 1,628 copy-number variations. We define 16 significantly mutated genes, reaffirming known mutations (KRAS, TP53, CDKN2A, SMAD4, MLL3, TGFBR2, ARID1A and SF3B1), and uncover novel mutated genes including additional genes involved in chromatin modification (EPC1 and ARID2), DNA damage repair (ATM) and other mechanisms (ZIM2, MAP2K4, NALCN, SLC16A4 and MAGEA6). Integrative analysis with in vitro functional data and animal models provided supportive evidence for potential roles for these genetic aberrations in carcinogenesis. Pathway-based analysis of recurrently mutated genes recapitulated clustering in core signalling pathways in pancreatic ductal adenocarcinoma, and identified new mutated genes in each pathway. We also identified frequent and diverse somatic aberrations in genes described traditionally as embryonic regulators of axon guidance, particularly SLIT/ROBO signalling, which was also evident in murine Sleeping Beauty transposon-mediated somatic mutagenesis models of pancreatic cancer, providing further supportive evidence for the potential involvement of axon guidance genes in pancreatic carcinogenesis.

  5. Aberrant behavior and cognitive ability in preschool children

    Directory of Open Access Journals (Sweden)

    Bala Gustav

    2007-01-01

    Full Text Available The sample included 712 preschool boys and girls at the age of 4 to 7 years (mean 5.96 decimal years and standard deviation .96 from preschool institutions in Novi Sad, Sombor, Sremska Mitrovica and Bačka Palanka. Information concerning 36 indicators of aberrant behavior of the children were supplied by their parents, whereas their cognitive ability was tested by Raven’s progressive colored matrices. Based on factor analysis (promax method, four factors i.e. generators of aberrant behavior in children were singled out: aggression, anxiousness, dissociation, and hysteria, whose relations with cognitive functioning and age were also analyzed by factor analysis. Aberrant behavior and cognitive abilities show significant interrelatedness. Owing to orderly developed cognitive abilities, a child understands essence and reality of problems, realizes possibilities and manners of solving them, and succeeds in realizing successful psycho-social functioning. Developed cognitive abilities enable a child to recognize and understand her/his own reactions in different situations and develop manners of reacting, which leads to strengthening psycho-social safety and adapting behavior in accordance with her/his age and abilities.

  6. Polarization Aberrations in Astronomical Telescopes: The Point Spread Function

    Science.gov (United States)

    Breckinridge, James B.; Lam, Wai Sze T.; Chipman, Russell A.

    2015-05-01

    Detailed knowledge of the image of the point spread function (PSF) is necessary to optimize astronomical coronagraph masks and to understand potential sources of errors in astrometric measurements. The PSF for astronomical telescopes and instruments depends not only on geometric aberrations and scalar wave diffraction but also on those wavefront errors introduced by the physical optics and the polarization properties of reflecting and transmitting surfaces within the optical system. These vector wave aberrations, called polarization aberrations, result from two sources: (1) the mirror coatings necessary to make the highly reflecting mirror surfaces, and (2) the optical prescription with its inevitable non-normal incidence of rays on reflecting surfaces. The purpose of this article is to characterize the importance of polarization aberrations, to describe the analytical tools to calculate the PSF image, and to provide the background to understand how astronomical image data may be affected. To show the order of magnitude of the effects of polarization aberrations on astronomical images, a generic astronomical telescope configuration is analyzed here by modeling a fast Cassegrain telescope followed by a single 90° deviation fold mirror. All mirrors in this example use bare aluminum reflective coatings and the illumination wavelength is 800 nm. Our findings for this example telescope are: (1) The image plane irradiance distribution is the linear superposition of four PSF images: one for each of the two orthogonal polarizations and one for each of two cross-coupled polarization terms. (2) The PSF image is brighter by 9% for one polarization component compared to its orthogonal state. (3) The PSF images for two orthogonal linearly polarization components are shifted with respect to each other, causing the PSF image for unpolarized point sources to become slightly elongated (elliptical) with a centroid separation of about 0.6 mas. This is important for both astrometry

  7. Effect of therapeutic hypothermia on chromosomal aberration in perinatal asphyxia

    Directory of Open Access Journals (Sweden)

    Bahubali D Gane

    2016-01-01

    Full Text Available Introduction: Perinatal asphyxia is a major cause for neonatal mortality and morbidity around the world. The reduction of O2results in the generation of reactive oxygen species which interact with nucleic acid and make alteration in the structure and functioning of the genome. We studied the effect of therapeutic hypothermia on chromosomes with karyotyping. Subjects and Methods: Babies in the hypothermia group were cooled for the first 72 h, using gel packs. Rectal temperature of 33–34°C was maintained. Blood sample was collected after completion of therapeutic hypothermia for Chromosomal analysis. It was done with IKAROS Karyotyping system, Metasystems, based on recommendations of International system of human cytogenetic nomenclature. Results: The median chromosomal aberration was lower in hypothermia [2(0-5] than control group [4(1-7] and chromatid breakage was commonest aberration seen. Chromosomal aberration was significantly higher in severe encephalopathy group than moderate encephalopathy group. Conclusion: We conclude that the TH significantly reduces DNA damage in perinatal asphyxia.

  8. Analysis of chromosome aberration data by hybrid-scale models

    Energy Technology Data Exchange (ETDEWEB)

    Indrawati, Iwiq [Research and Development on Radiation and Nuclear Biomedical Center, National Nuclear Energy Agency (Indonesia); Kumazawa, Shigeru [Nuclear Technology and Education Center, Japan Atomic Energy Research Institute, Honkomagome, Tokyo (Japan)

    2000-02-01

    This paper presents a new methodology for analyzing data of chromosome aberrations, which is useful to understand the characteristics of dose-response relationships and to construct the calibration curves for the biological dosimetry. The hybrid scale of linear and logarithmic scales brings a particular plotting paper, where the normal section paper, two types of semi-log papers and the log-log paper are continuously connected. The hybrid-hybrid plotting paper may contain nine kinds of linear relationships, and these are conveniently called hybrid scale models. One can systematically select the best-fit model among the nine models by among the conditions for a straight line of data points. A biological interpretation is possible with some hybrid-scale models. In this report, the hybrid scale models were applied to separately reported data on chromosome aberrations in human lymphocytes as well as on chromosome breaks in Tradescantia. The results proved that the proposed models fit the data better than the linear-quadratic model, despite the demerit of the increased number of model parameters. We showed that the hybrid-hybrid model (both variables of dose and response using the hybrid scale) provides the best-fit straight lines to be used as the reliable and readable calibration curves of chromosome aberrations. (author)

  9. A survey of chromosomal aberrations in lymphocytes of Chernobyl liquidators

    Energy Technology Data Exchange (ETDEWEB)

    Sevan`kaev, A.V.; Moiseenko, V.V.; Zhloba, A.A. [Medical Radiological Research Centre, Obninsk (Russian Federation); Lloyd, D.C.; Edwards, A.A. [National Radiological Protection Board, Chilton (United Kingdom); Braselmann, H. [G.S.F. Institut fuer Strahlenbiologie (Germany)

    1995-04-01

    Chromosomal aberrations in lymphocytes of 875 Chernobyl liquidators have been scored and by comparison with control subjects the dicentric plus ring and excess acentric fragment frequencies are higher for persons who worked in the exclusion zone in 1986-1988 but not in 1989. Aberration yields are too low for individual biological dosimetry but, after taking account of the time interval between irradiation and blood sampling, the dicentric plus ring frequencies indicate average doses for 1986, 1987 and 1989 in good agreement with the annual averages in the Obninsk Registry. For 1988 the cytogenetic data indicate a significant higher average dose than the Registry. Liquidators who were not issued with a personal film badge tend to have higher aberration yields than those for whom badge data are recorded. This is particularly evident for those persons who worked in the first three months after the accident where physical dosimetry data are less complete or reliable. The persons probably experienced the highest exposures of all liquidators and the chromosomal data suggest an average value of about 300 mGy. (author).

  10. Chromosome aberrations in ataxia telangiectasia cells exposed to heavy ions

    Science.gov (United States)

    Kawata, T.; Cucinotta, F.; George, K.; Wu, H.; Shigematsu, N.; Furusawa, Y.; Uno, T.; Isobe, K.; Ito, H.

    Understanding of biological effects of heavy ions is important to assess healt h risk in space. One of the most important issues may be to take into account individual susceptibility. Ataxia telangiectasia (A-T) cells are known to exhibit abnormal responses to radiations but the mechanism of hyper radiosensitivity of A-T still remains unknown. We report chromosome aberrations in normal human fibroblasts and AT fibroblasts exposed to low- and high-LET radiations. A chemical-induced premature chromosome condensation (PCC) technique combined with chromosome- painting technique was applied to score chromosome aberrations in G2/M-phase cells. Following gamma irradiation, GM02052 cells were approximately 5 times more sensitive to g-rays than AG1522 cells. GM02052 cells had a much higher frequency of deletions and misrejoining than AG1522 cells. When the frequency of complex type aberrations was compared, GM02052 cells showed more than 10 times higher frequency than AG1522 cells. The results will be compared with those obtained from high-LET irradiations.

  11. Estimation of phase wave-front aberration distribution function using wavelet transform profilometry.

    Science.gov (United States)

    Rahbar, Kambiz; Faez, Karim; Attaran-Kakhki, Ebrahim

    2012-06-01

    Reduction of image quality under the effects of wavefront aberration of the optical system has a direct impact on the vision system's performance. This paper tries to estimate the amount of aberration with the use of wavelet transform profilometry. The basic idea is based on the principle that under aberration effects, the position of the fringes' image on the image plane will change, and this change correlates with the amount of aberration. So the distribution of aberration function can directly be extracted through measuring the amount of changes in the fringes' image on the image plane. Experimental results and the empirical validity of this idea are evaluated.

  12. Disruption of microtubule network rescues aberrant actin comets in dynamin2-depleted cells.

    Directory of Open Access Journals (Sweden)

    Yuji Henmi

    Full Text Available A large GTPase dynamin, which is required for endocytic vesicle formation, regulates the actin cytoskeleton through its interaction with cortactin. Dynamin2 mutants impair the formation of actin comets, which are induced by Listeria monocytogenes or phosphatidylinositol-4-phosphate 5-kinase. However, the role of dynamin2 in the regulation of the actin comet is still unclear. Here we show that aberrant actin comets in dynamin2-depleted cells were rescued by disrupting of microtubule networks. Depletion of dynamin2, but not cortactin, significantly reduced the length and the speed of actin comets induced by Listeria. This implies that dynamin2 may regulate the actin comet in a cortactin-independent manner. As dynamin regulates microtubules, we investigated whether perturbation of microtubules would rescue actin comet formation in dynamin2-depleted cells. Treatment with taxol or colchicine created a microtubule-free space in the cytoplasm, and made no difference between control and dynamin2 siRNA cells. This suggests that the alteration of microtubules by dynamin2 depletion reduced the length and the speed of the actin comet.

  13. MLL5 maintains spindle bipolarity by preventing aberrant cytosolic aggregation of PLK1.

    Science.gov (United States)

    Zhao, Wei; Liu, Jie; Zhang, Xiaoming; Deng, Lih-Wen

    2016-03-28

    Faithful chromosome segregation with bipolar spindle formation is critical for the maintenance of genomic stability. Perturbation of this process often leads to severe mitotic failure, contributing to tumorigenesis. MLL5 has been demonstrated to play vital roles in cell cycle progression and the maintenance of genomic stability. Here, we identify a novel interaction between MLL5 and PLK1 in the cytosol that is crucial for sustaining spindle bipolarity during mitosis. Knockdown of MLL5 caused aberrant PLK1 aggregation that led to acentrosomal microtubule-organizing center (aMTOC) formation and subsequent spindle multipolarity. Further molecular studies revealed that the polo-box domain (PBD) of PLK1 interacted with a binding motif on MLL5 (Thr887-Ser888-Thr889), and this interaction was essential for spindle bipolarity. Overexpression of wild-type MLL5 was able to rescue PLK1 mislocalization and aMTOC formation in MLL5-KD cells, whereas MLL5 mutants incapable of interacting with the PBD failed to do so. We thus propose that MLL5 preserves spindle bipolarity through maintaining cytosolic PLK1 in a nonaggregated form. PMID:27002166

  14. Aberration-Coreected Electron Microscopy at Brookhaven National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Zhu,Y.; Wall, J.

    2008-04-01

    The last decade witnessed the rapid development and implementation of aberration correction in electron optics, realizing a more-than-70-year-old dream of aberration-free electron microscopy with a spatial resolution below one angstrom [1-9]. With sophisticated aberration correctors, modern electron microscopes now can reveal local structural information unavailable with neutrons and x-rays, such as the local arrangement of atoms, order/disorder, electronic inhomogeneity, bonding states, spin configuration, quantum confinement, and symmetry breaking [10-17]. Aberration correction through multipole-based correctors, as well as the associated improved stability in accelerating voltage, lens supplies, and goniometers in electron microscopes now enables medium-voltage (200-300kV) microscopes to achieve image resolution at or below 0.1nm. Aberration correction not only improves the instrument's spatial resolution but, equally importantly, allows larger objective lens pole-piece gaps to be employed thus realizing the potential of the instrument as a nanoscale property-measurement tool. That is, while retaining high spatial resolution, we can use various sample stages to observe the materials response under various temperature, electric- and magnetic- fields, and atmospheric environments. Such capabilities afford tremendous opportunities to tackle challenging science and technology issues in physics, chemistry, materials science, and biology. The research goal of the electron microscopy group at the Dept. of Condensed Matter Physics and Materials Science and the Center for Functional Nanomaterials, as well as the Institute for Advanced Electron Microscopy, Brookhaven National Laboratory (BNL), is to elucidate the microscopic origin of the physical- and chemical-behavior of materials, and the role of individual, or groups of atoms, especially in their native functional environments. We plan to accomplish this by developing and implementing various quantitative

  15. Effect of spherical aberration on scintillations of Gaussian beams in atmospheric turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Xiaoling, E-mail: jiXL100@163.com; Deng, Jinping

    2014-07-18

    The effect of spherical aberration on scintillations of Gaussian beams in weak, moderate and strong turbulence is studied using numerical simulation method. It is found that the effect of the negative spherical aberration on the on-axis scintillation index is quite different from that of the positive spherical aberration. In weak turbulence, the positive spherical aberration results in a decrease of the on-axis scintillation index on propagation, but the negative spherical aberration results in an increase of the on-axis scintillation index when the propagation distance is not large. In particular, in weak turbulence the negative spherical aberration may cause peaks of the on-axis scintillation index, and the peaks disappear in moderate and strong turbulence, which is explained in physics. The strong turbulence leads to less discrepancy among scintillations of Gaussian beams with and without spherical aberration. - Highlights: • In weak turbulence scintillations can be suppressed using positive spherical aberration. • In weak turbulence scintillations may be very large due to negative spherical aberration. • The effect of spherical aberration on scintillations is less with increasing of turbulence.

  16. Influence of Misalignment on High-Order Aberration Correction for Normal Human Eyes

    Institute of Scientific and Technical Information of China (English)

    ZHAO Hao-Xin; XU Bing; XUE Li-Xia; DAI Yun; LIU Qian; RAO Xue-Jun

    2008-01-01

    @@ Although a compensation device can correct aberrations of human eyes, the effect will be degraded by its misalignment, especially for high-order aberration correction. We caJculate the positioning tolerance of correction device for high-order aberrations, and within what degree the correcting effect is better than low-order aberration (defocus and astigmatism) correction. With fixed certain misalignment within the positioning tolerance, we calculate the residual wavefront rms aberration of the first-6 to first-35 terms along with the 3rd-5th terms of aberrations corrected, and the combined first-13 terms of aberrations are also studied under the same quantity of misalignment. However, the correction effect of high-order aberrations does not meliorate along with the increase of the high-order terms under some misalignment, moreover, some simple combined terms correction can achieve similar result as complex combinations. These results suggest that it is unnecessary to correct too much the terms of high-order aberrations which are diffcult to accomplish in practice, and gives confdence to correct high-order aberrations out of the laboratory.

  17. Breast tumor copy number aberration phenotypes and genomic instability

    International Nuclear Information System (INIS)

    Genomic DNA copy number aberrations are frequent in solid tumors, although the underlying causes of chromosomal instability in tumors remain obscure. Genes likely to have genomic instability phenotypes when mutated (e.g. those involved in mitosis, replication, repair, and telomeres) are rarely mutated in chromosomally unstable sporadic tumors, even though such mutations are associated with some heritable cancer prone syndromes. We applied array comparative genomic hybridization (CGH) to the analysis of breast tumors. The variation in the levels of genomic instability amongst tumors prompted us to investigate whether alterations in processes/genes involved in maintenance and/or manipulation of the genome were associated with particular types of genomic instability. We discriminated three breast tumor subtypes based on genomic DNA copy number alterations. The subtypes varied with respect to level of genomic instability. We find that shorter telomeres and altered telomere related gene expression are associated with amplification, implicating telomere attrition as a promoter of this type of aberration in breast cancer. On the other hand, the numbers of chromosomal alterations, particularly low level changes, are associated with altered expression of genes in other functional classes (mitosis, cell cycle, DNA replication and repair). Further, although loss of function instability phenotypes have been demonstrated for many of the genes in model systems, we observed enhanced expression of most genes in tumors, indicating that over expression, rather than deficiency underlies instability. Many of the genes associated with higher frequency of copy number aberrations are direct targets of E2F, supporting the hypothesis that deregulation of the Rb pathway is a major contributor to chromosomal instability in breast tumors. These observations are consistent with failure to find mutations in sporadic tumors in genes that have roles in maintenance or manipulation of the genome

  18. Construction of minimum generalized aberration two-level orthogonal arrays

    OpenAIRE

    Evangelaras, Haralambos

    2015-01-01

    In this paper we explore the problem of constructing two-level Minimum Generalized Aberration (MGA) orthogonal arrays with strength $t$, $n$ runs and $q>t$ columns, using a method that employs the $J$-characteristics of a two-level design. General results for the construction of MGA orthogonal arrays with $t+1$, $t+2$ and $t+3$ columns are given, while all MGA designs with strength $t\\ge 2$, $n \\equiv$ 0 mod 4 runs and $q\\le 6$ are constructed. Results are also given for two-level orthogonal ...

  19. Propagation of aberrated wavefronts using a ray transfer matrix.

    Science.gov (United States)

    Raasch, Thomas W

    2014-05-01

    A ray transfer matrix is used to calculate the propagation of aberrated wavefronts across a homogeneous refractive index. The wavefront is represented by local surface normals, i.e., by a ray bundle, and the propagation is accomplished by transferring those rays across the space. Wavefront shape is generated from the slopes and positions of the collection of rays. Calculation methods are developed for the paraxial case, for higher-order expansions, and for the exact tangent case. A numerical example is used to compare results between an analytical method and the methods developed here.

  20. Spatially incoherent illumination interferometry: a PSF almost insensitive to aberrations

    CERN Document Server

    Xiao, Peng; Boccara, A Claude

    2016-01-01

    We show that with spatially incoherent illumination, the point spread function width of an imaging interferometer like that used in full-field optical coherence tomography (FFOCT) is almost insensitive to aberrations that mostly induce a reduction of the signal level without broadening. This is demonstrated by comparison with traditional scanning OCT and wide-field OCT with spatially coherent illuminations. Theoretical analysis, numerical calculation as well as experimental results are provided to show this specific merit of incoherent illumination in full-field OCT. To the best of our knowledge, this is the first time that such result has been demonstrated.

  1. Generic Misalignment Aberration Patterns and the Subspace of Benign Misalignment

    CERN Document Server

    Schechter, Paul L

    2012-01-01

    Q1: Why deploy N wavefront sensors on a three mirror anastigmat (TMA) and not N + 1? Q2: Why measure M Zernike coefficients and not M + 1? Q3: Why control L rigid body degrees of freedom (total) on the secondary and tertiary and not L + 1? The usual answer: "We did a lot of ray tracing and N,M, and L seemed OK." We show how straightforward results from aberration theory may be used to address these questions. We consider, in particular, the case of a three mirror anastigmat.

  2. ∆DNMT3B4-del Contributes to Aberrant DNA Methylation Patterns in Lung Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Mark Z. Ma

    2015-10-01

    Full Text Available Aberrant DNA methylation is a hallmark of cancer but mechanisms contributing to the abnormality remain elusive. We have previously shown that ∆DNMT3B is the predominantly expressed form of DNMT3B. In this study, we found that most of the lung cancer cell lines tested predominantly expressed DNMT3B isoforms without exons 21, 22 or both 21 and 22 (a region corresponding to the enzymatic domain of DNMT3B termed DNMT3B/∆DNMT3B-del. In normal bronchial epithelial cells, DNMT3B/ΔDNMT3B and DNMT3B/∆DNMT3B-del displayed equal levels of expression. In contrast, in patients with non-small cell lung cancer NSCLC, 111 (93% of the 119 tumors predominantly expressed DNMT3B/ΔDNMT3B-del, including 47 (39% tumors with no detectable DNMT3B/∆DNMT3B. Using a transgenic mouse model, we further demonstrated the biological impact of ∆DNMT3B4-del, the ∆DNMT3B-del isoform most abundantly expressed in NSCLC, in global DNA methylation patterns and lung tumorigenesis. Expression of ∆DNMT3B4-del in the mouse lungs resulted in an increased global DNA hypomethylation, focal DNA hypermethylation, epithelial hyperplastia and tumor formation when challenged with a tobacco carcinogen. Our results demonstrate ∆DNMT3B4-del as a critical factor in developing aberrant DNA methylation patterns during lung tumorigenesis and suggest that ∆DNMT3B4-del may be a target for lung cancer prevention.

  3. MITOSIS ANA-THELOPHASE CHROMOSOMAL ABERRATIONS INDUCED BY UV IRRADIATION UNDER THE ANTIOXIDATIVE PROTECTION OF VITAMIN C, BY CALENDULA OFFICINALIS L.

    Directory of Open Access Journals (Sweden)

    Csilla Iuliana Bara

    2014-07-01

    Full Text Available due to the stratospheric ozone layer depletion, the researches focused in the last decades on the study of solarradiations reaching Earth surface. The target of the study was to establish the biological response of Calendula officinalisL. to UV irradiation, under the anti-oxidative protection of vitamin C, (which helps next to UV induced anti-oxidativeenzymes, in the protection against a large variety of products capable to induce free radicals formation.Our investigations were focused on detecting chromosomal aberrations which occurs during cells in division in meristemroot tips, under UV irradiation for 15 or 30 minutes, in the presence or absence of vitamin C, reported to the non-irradiated control samples. Regarding the mitotic index, it could be noticed an inhibition of cell division frequency underUV stress for all irradiated variants, not depending of presence or absence of vitamin C, positively correlated with theincrease of irradiation period. Maximal chromosomal aberrations frequency, were induced by UV radiations in the roottips of seedlings germinated in the absence of vitamin C, decreasing in the presence of vitamin C, due to the antioxidantprotective role of this. In the absence of UV irradiation, the chromosomal aberrations frequency was lower comparingwith irradiated variants, for all seedlings, even if germinated in the presence or absence of vitamin C. Betweenchromosomal aberrations were detected: bridges, expulsed and retardate chromosomes, fragments.

  4. Explanation of test and assessment of chromosomal aberrations on occupational health examinations for radiation workers

    International Nuclear Information System (INIS)

    Test and Assessment of Chromosomal Aberrations on Occupational Health Examinations for Radiation Workers was formulated for standardizing analysis and outcome assessment of chromosomal aberrations on occupational health examinations for radiation workers. In order to provide experimental and theoretical basis for implementation and extension of this standard, this paper interpreted the standard comprehensively, including some existed problems that methods on detection and outcome assessment of chromosomal aberrations is not unified in different laboratories in China, and related criteria,laws and regulations at home and abroad are not fit for the detection of chromosomal aberrations for radiation workers very well; some introduction on methods of chromosomal slide preparation, discriminant analysis and outcome assessment of chromosomal aberration; and some influencing factors in the quality of chromosomal aberration detection. (authors)

  5. Influence of spherical aberrations on fundamental mode beam quality under different laser resonators

    Institute of Scientific and Technical Information of China (English)

    Xiang Zhen; Hu Miao; Ge Jian-Hong; Zhao Zhi-Gang; Wang Sha; Liu Chong; Chen Jun

    2009-01-01

    Spherical aberrations of the thermal lens of the active media are severe when solid state lasers are strongly pumped.The fundamental mode profile deteriorates due to the aberrations. Self-consistent modes of a resonator with aberrations are calculated by using the Fox-Li diffraction iterative algorithm. Calculation results show that the aberration induced fundamental mode beam quality deterioration depends greatly on the resonator design. The tolerance of a flat-flat resonator to the aberration coefficient is about 30λ in the middle of stability, where λ is the wavelength of laser beam. But for a dynamically stable resonator, 2λ of spherical aberration will create diffraction loss of more than 40%, if inappropriate design criteria are used. A birefringence compensated laser resonator with two Nd:YAG rods is experimentally studied. The experimental data are in quite good agreement with simulation results.

  6. Effects of Turbulent Aberrations on Probability Distribution of Orbital Angular Momentum for Optical Communication

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yi-Xin; CANG Ji

    2009-01-01

    Effects of atmospheric turbulence tilt, defocus, astigmatism and coma aberrations on the orbital angular mo-mentum measurement probability of photons propagating in weak turbulent regime are modeled with Rytov approximation. By considering the resulting wave as a superposition of angular momentum eigenstates, the or-bital angular momentum measurement probabilities of the transmitted digit axe presented. Our results show that the effect of turbulent tilt aberration on the orbital angular momentum measurement probabilities of photons is the maximum among these four kinds of aberrations. As the aberration order increases, the effects of turbulence aberrations on the measurement probabilities of orbital angular momentum generally decrease, whereas the effect of turbulence defoens can be ignored. For tilt aberration, as the difference between the measured orbital angular momentum and the original orbital angular momentum increases, the orbital angular momentum measurement probabifity decreases.

  7. An experimental study of aero-optical aberration and dithering of supersonic mixing layer via BOS

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The optical performance of supersonic mixing layer is heavily deteriorated by the aero-optical aberration and dithering of coherent structures, but current measuring methods limit the spatiotemporal resolution in relevant studies. A high resolution whole-field aero-optical aberration and dithering measuring method based on the Background Orient Schlieren (BOS) technique was studied. The systematic structure, sensitivity and resolution of BOS are analyzed in this paper. The aero-optical aberration and dithering of streamwise structures in supersonic mixing layers were quantificationally studied with BOS. The aberration field of spanwise structures revealed the ribbon-like aberration structures, which heavily restrict the optical performance of a mixing layer. The quantifications of aero-optical aberration and dithering are very important in studying aero-optical performance of supersonic mixing layer.

  8. Ray and Wave Aberrations Revisited: A Huygens Construction yields Exact Relations

    CERN Document Server

    Restrepo, John; Ihrke, Ivo

    2015-01-01

    The optical aberrations of a system can be described in terms of the wave aberrations, defined as the departure from the ideal spherical wavefront; or the ray aberrations, which are in turn the deviations from the paraxial ray intersection measured in the image plane. The classical connection between the two descriptions is an approximation, the error of which has, so far, not been quantified analytically. We derive exact analytical equations for computing the wavefront surface, the aberrated ray directions, and the transverse ray aberrations in terms of the wave aberrations (OPD) and the reference sphere. We introduce precise conditions for a function to be an OPD function, show that every such function has an associated wavefront, and study the error arising from the classical approximation. We establish strict conditions for the error to be small. We illustrate our results with numerical simulations. Our results show that large numerical apertures and high-frequency OPD functions yield larger approximation...

  9. Ray and wave aberrations revisited: a Huygens-like construction yields exact relations.

    Science.gov (United States)

    Restrepo, John; Stoerck, Pawel J; Ihrke, Ivo

    2016-02-01

    The aberrations of an optical system can be described in terms of the wave aberrations, defined as the departure from the ideal spherical wavefront; or the ray aberrations, which are in turn the deviations from the paraxial ray intersections measured in the image plane. The classical connection between the two descriptions is an approximation, the error of which has, to our knowledge, so far not been quantified analytically. We derive exact analytical equations for computing the wavefront surface, the aberrated ray directions, and the transverse ray aberrations in terms of the wave aberrations (OPD) and the reference sphere. We introduce precise conditions for a function to be an OPD function, show that every such function has an associated wavefront, and study the error arising from the classical approximation. We establish strict conditions for the error to be small. We illustrate our results with numerical simulations. Our results show that large numerical apertures and OPD functions with strong gradients yield larger approximation errors.

  10. Mechanistic modeling of aberrant energy metabolism in human disease

    Directory of Open Access Journals (Sweden)

    Vineet eSangar

    2012-10-01

    Full Text Available Dysfunction in energy metabolism—including in pathways localized to the mitochondria—has been implicated in the pathogenesis of a wide array of disorders, ranging from cancer to neurodegenerative diseases to type II diabetes. The inherent complexities of energy and mitochondrial metabolism present a significant obstacle in the effort to understand the role that these molecular processes play in the development of disease. To help unravel these complexities, systems biology methods have been applied to develop an array of computational metabolic models, ranging from mitochondria-specific processes to genome-scale cellular networks. These constraint-based models can efficiently simulate aspects of normal and aberrant metabolism in various genetic and environmental conditions. Development of these models leverages—and also provides a powerful means to integrate and interpret—information from a wide range of sources including genomics, proteomics, metabolomics, and enzyme kinetics. Here, we review a variety of mechanistic modeling studies that explore metabolic functions, deficiency disorders, and aberrant biochemical pathways in mitochondria and related regions in the cell.

  11. Correction for polychromatic aberration in computed tomography images

    International Nuclear Information System (INIS)

    A method and apparatus for correcting a computed tomography image for polychromatic aberration caused by the non-linear interaction (i.e. the energy dependent attenuation characteristics) of different body constituents, such as bone and soft tissue, with a polychromatic X-ray beam are described in detail. An initial image is conventionally computed from path measurements made as source and detector assembly scan a body section. In the improvement, each image element of the initial computed image representing attenuation is recorded in a store and is compared with two thresholds, one representing bone and the other soft tissue. Depending on the element value relative to the thresholds, a proportion of the respective constituent is allocated to that element location and corresponding bone and soft tissue projections are determined and stored. An error projection generator calculates projections of polychromatic aberration errors in the raw image data from recalled bone and tissue projections using a multidimensional polynomial function which approximates the non-linear interaction involved. After filtering, these are supplied to an image reconstruction computer to compute image element correction values which are subtracted from raw image element values to provide a corrected reconstructed image for display. (author)

  12. Correction of optical aberrations in elliptic neutron guides

    Energy Technology Data Exchange (ETDEWEB)

    Bentley, Phillip M., E-mail: phillip.bentley@esss.se [Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); European Spallation Source ESS AB, Box 176, 221 00 Lund (Sweden); Kennedy, Shane J. [Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Andersen, Ken H. [European Spallation Source ESS AB, Box 176, 221 00 Lund (Sweden); Martin Rodriguez, Damian [Juelich Centre for Neutron Science, Forschungszentrum Juelich GmbH, 52425 Juelich (Germany); Mildner, David F.R. [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States)

    2012-11-21

    Modern, nonlinear ballistic neutron guides are an attractive concept in neutron beam delivery and instrumentation because they offer increased performance over straight or linearly tapered guides. However, like other ballistic geometries they have the potential to create significantly non-trivial instrumental resolution functions. We address the source of the most prominent optical aberration, namely coma, and we show that for extended sources the off-axis rays have a different focal length from on-axis rays, leading to multiple reflections in the guide system. We illustrate how the interplay between coma, sources of finite size, and mirrors with non-perfect reflectivity can therefore conspire to produce uneven distributions in the neutron beam divergence, a source of complicated resolution functions. To solve these problems, we propose a hybrid elliptic-parabolic guide geometry. Using this new kind of neutron guide shape, it is possible to condition the neutron beam and remove almost all of the aberrations, whilst providing the same performance in beam current as a standard elliptic neutron guide. We highlight the positive implications for neutron scattering instruments that this new shape can bring.

  13. Exercise protects against methamphetamine-induced aberrant neurogenesis

    Science.gov (United States)

    Park, Minseon; Levine, Harry; Toborek, Michal

    2016-01-01

    While no effective therapy is available for the treatment of methamphetamine (METH)-induced neurotoxicity, aerobic exercise is being proposed to improve depressive symptoms and substance abuse outcomes. The present study focuses on the effect of exercise on METH-induced aberrant neurogenesis in the hippocampal dentate gyrus in the context of the blood-brain barrier (BBB) pathology. Mice were administered with METH or saline by i.p. injections for 5 days with an escalating dose regimen. One set of mice was sacrificed 24 h post last injection of METH, and the remaining animals were either subjected to voluntary wheel running (exercised mice) or remained in sedentary housing (sedentary mice). METH administration decreased expression of tight junction (TJ) proteins and increased BBB permeability in the hippocampus. These changes were preserved post METH administration in sedentary mice and were associated with the development of significant aberrations of neural differentiation. Exercise protected against these effects by enhancing the protein expression of TJ proteins, stabilizing the BBB integrity, and enhancing the neural differentiation. In addition, exercise protected against METH-induced systemic increase in inflammatory cytokine levels. These results suggest that exercise can attenuate METH-induced neurotoxicity by protecting against the BBB disruption and related microenvironmental changes in the hippocampus. PMID:27677455

  14. Chromosome aberrations in workers of beach sand mineral industries

    International Nuclear Information System (INIS)

    Beach Sand Mining (BSM) is a profitable industry earning a sizable income for the country by way of foreign exchange. The Indian coast is rich in rare earths such as ilmenite, rutile, leucoxene, zircon, garnet and sillimanite, and is invariably associated with radioactive monazite. Due to the nature of the separation processes involved and the manual handling, workers in these factories are continuously being exposed to suspended particles containing naturally occurring radioactive materials. An attempt was made to estimate DNA damage using a chromosome aberration assay to monitor radiation effects in workers of BSM industries in India. The study group comprised 27 BSM workers and 20 controls. Percentage yields of dicentrics, acentric fragments and chromatid breaks observed in the control group were 0.058 ± 0.017, 0.073 ± 0.03 and 0.22 ± 0.112, respectively. Percentage yields of dicentrics + centric rings, acentric fragments and chromatid breaks observed in the BSM group were 0.029 ± 0.01 (P value 0.19), 0.24 ± 0.06 (P value 0.006) and 0.455 ± 0.06 (P value 0.0004), respectively. Elevated levels of fragments and chromatid aberrations are suggestive of low-dose radiation effects and also chemically-induced DNA damage. (authors)

  15. Aberrant activity in degenerated retinas revealed by electrical imaging

    Directory of Open Access Journals (Sweden)

    Günther eZeck

    2016-02-01

    Full Text Available In this review I present and discuss the current understanding of aberrant electrical activity found in the ganglion cell layer (GCL of rod-degenerated (rd mouse retinas. The reported electrophysiological properties revealed by electrical imaging using high-density microelectrode arrays can be subdivided between spiking activity originating from retinal ganglion cells (RGCs and local field potentials reflecting strong trans-membrane currents within the GCL. RGCs in rod-degenerated retinas show increased and rhythmic spiking compared to age-matched wild-type retinas. Fundamental spiking frequencies range from 5 to 15 Hz in various mouse models. The rhythmic RGC spiking is driven by a presynaptic network comprising AII amacrine and bipolar cells. In the healthy retina this rhythm-generating circuit is inhibited by photoreceptor input. A unique physiological feature of rd retinas is rhythmic local field potentials (LFP manifested as spatially-restricted low-frequency (5–15 Hz voltage changes. Their spatiotemporal characterization revealed propagation and correlation with RGC spiking. LFPs rely on gap-junctional coupling and are shaped by glycinergic and by GABAergic transmission. The aberrant RGC spiking and LFPs provide a simple readout of the functionality of the remaining retinal circuitry which can be used in the development of improved vision restoration strategies.

  16. Chromosomal aberrations as etiological factors of intrauterine growth retardation

    Directory of Open Access Journals (Sweden)

    Petrović Bojana

    2008-01-01

    Full Text Available Background/Aim. Intrauterine growth retardation (IUGR is a pathological condition of pregnancy characterised by birth weight below the 10th centile. A number of fetal, placental and maternal causes can lead to IUGR; although, in most cases no specific causes can be identified. The aim of this study was to determine the part of chromosomal abnormalities in IUGR etiology. Methods. Fetal blood karyotype taken by cordocentesis from 168 fetuses with diagnosed IUGR was analyzed. Results. Chromosomal rearrangements both numerical and structural were detected in 14 cases (12.2%. Two cases were triploid. Patau syndrome, Edwards syndrome and Down syndrome were found in two cases each. There was one case of trisomy 7 (47, XY, +7 and one case of trisomy 16 (47, XX, +16; one translocation, 46, XY, t (2; 14(q23; q32 and a deletion 46, XYdel (12 (p12 as well as two cases of sex chromosomes abnormalities, 45, X (Turner syndrome and 47, XYY. Conclusion. These findings suggest that a consistent number of symmetrical IUGR cases (about 12% can be associated with chromosomal rearrangements. Chromosomal aberrations that cause IUGR are heterogeneous, aberration of autosomes, mostly autosomal trisomies, being the most common.

  17. Maternal age, reproduction and chromosomal aberrations in Wistar derived rats.

    Science.gov (United States)

    Niggeschulze, A; Kast, A

    1994-01-01

    The fertility of rats ranges from one to 18 months. In standard teratogenicity testing young, mature females are used which may not reflect the situation in women above 35 years old. Reproduction among different age groups of Wistar ats (strain Chbb: THOM) was compared at 3, 6, 9, 12, 15 and 18 months. At least 20 virgin females were inseminated per age group. The copulation rate did not differ between the groups. From the maternal age of 12 months, the pregnancy rate was significantly decreased, from the age of 9 months, the litter values were significantly lowered and the resorption rates were increased. Maternal age did not influence the incidence of fetal variations and malformations. Additionally, the chromosomal aberration rate in the bone marrow was evaluated in male and female rats. Twelve animals of each sex were scheduled per group, and studied at the age of 1, 3, 6, 12, 15, 18, 21 or 24 months. In males, the aberration rate increased continuously from 0.18 through 3%, while in females the increase continued from 0.33 to 2.29% at 15 months old when a plateau was reached. When testing new compounds for embryotoxicity or genotoxicity in female rats, the animals should be of comparable age to man in order to avoid a misinterpretation of spontaneous abnormalities. From these studies, however, it was concluded that the use of higher age groups of female rats in teratogenicity studies would not improve the risk assessment.

  18. Aberrant WNT/β-catenin signaling in parathyroid carcinoma

    Directory of Open Access Journals (Sweden)

    Åkerström Göran

    2010-11-01

    Full Text Available Abstract Background Parathyroid carcinoma (PC is a very rare malignancy with a high tendency to recur locally, and recurrent disease is difficult to eradicate. In most western European countries and United States, these malignant neoplasms cause less than 1% of the cases with primary hyperparathyroidism, whereas incidence as high as 5% have been reported from Italy, Japan, and India. The molecular etiology of PC is poorly understood. Results The APC (adenomatous polyposis coli tumor suppressor gene was inactivated by DNA methylation in five analyzed PCs, as determined by RT-PCR, Western blotting, and quantitative bisulfite pyrosequencing analyses. This was accompanied by accumulation of stabilized active nonphosphorylated β-catenin, strongly suggesting aberrant activation of the WNT/β-catenin signaling pathway in these tumors. Treatment of a primary PC cell culture with the DNA hypomethylating agent 5-aza-2'-deoxycytidine (decitabine, Dacogen(r induced APC expression, reduced active nonphosphorylated β-catenin, inhibited cell growth, and caused apoptosis. Conclusion Aberrant WNT/β-catenin signaling by lost expression and DNA methylation of APC, and accumulation of active nonphosphorylated β-catenin was observed in the analyzed PCs. We suggest that adjuvant epigenetic therapy should be considered as an additional option in the treatment of patients with recurrent or metastatic parathyroid carcinoma.

  19. Expression of aberrant forms of AUXIN RESPONSE FACTOR8 stimulates parthenocarpy in Arabidopsis and tomato.

    Science.gov (United States)

    Goetz, Marc; Hooper, Lauren C; Johnson, Susan D; Rodrigues, Julio Carlyle Macedo; Vivian-Smith, Adam; Koltunow, Anna M

    2007-10-01

    Fruit initiation in Arabidopsis (Arabidopsis thaliana) is generally repressed until fertilization occurs. However, mutations in AUXIN RESPONSE FACTOR8 (ARF8) uncouple fruit initiation from fertilization, resulting in the formation of seedless, parthenocarpic fruit. Here we induced parthenocarpy in wild-type Arabidopsis by introducing either the mutant genomic (g) Atarf8-4 sequence or gAtARF8:beta-glucuronidase translational fusion constructs by plant transformation. Silencing of endogenous AtARF8 transcription was not observed, indicating that the introduced, aberrant ARF8 transcripts were compromising the function of endogenous ARF8 and/or associated factors involved in suppressing fruit initiation. To analyze the role of ARF8 in tomato (Solanum lycopersicum) we initially emasculated 23 tomato cultivars to test for background parthenocarpy. Surprisingly, all had a predisposition to initiate fertilization-independent fruit growth. Expression of gAtarf8-4 in transgenic tomato ('Monalbo') resulted in a significant increase in the number and size of parthenocarpic fruit. Isolation of tomato ARF8 cDNA indicated significant sequence conservation with AtARF8. SlARF8 may therefore control tomato fruit initiation in a similar manner as AtARF8 does in Arabidopsis. Two SlARF8 cDNAs differing in size by 5 bp were found, both arising from the same gene. The smaller cDNA is a splice variant and is also present in Arabidopsis. We propose that low endogenous levels of the splice variant products might interfere with efficient formation/function of a complex repressing fruit initiation, thereby providing an explanation for the observed ovary expansion in tomato and also Arabidopsis after emasculation. Increasing the levels of aberrant Atarf8-4 transcripts may further destabilize formation/function of the complex in a dosage-dependent manner enhancing tomato parthenocarpic fruit initiation frequency and size and mimicking the parthenocarpic dehiscent silique phenotype found in

  20. ANALYSES OF CHROMOSOME ABERRATIONS IN LYMPHOCYTES AND BONE MARROW CELLS INDUCED BY RADIATION OR BENZENE

    Institute of Scientific and Technical Information of China (English)

    张鸿源; 王兰金; 等

    1995-01-01

    The chromosomoe and chromatid type aberration can be induced by benzene and the dicentric and ring ones were not observed in vitro experiment but observed in vivo one.In vitro experiment a good linear reression can be given between benzene concentrations and total aberration cells while power regression for radiation dose.The chromosome aberrations induced by benzene combined with radiation in rabbit blood lymphocytes are higher than in bone marryow cells.

  1. Correction of cell-induced optical aberrations in a fluorescence fluctuation microscope.

    OpenAIRE

    Leroux, Charles-Edouard; Grichine, Alexei; Wang, Irène; Delon, Antoine

    2013-01-01

    International audience We describe the effect of optical aberrations on fluorescence fluctuations microscopy (FFM), when focusing through a single living cell. FFM measurements are performed in an aqueous fluorescent solution and prove to be a highly sensitive tool to assess the optical aberrations introduced by the cell. We demonstrate an adaptive optics (AO) system to remove the aberration-related bias in the FFM measurements. Our data show that AO is not only useful when imaging deep in...

  2. EVALUATION OF CORRECTION METHODS OF CHROMATIC ABERRATION IN DIGITAL CAMERA IMAGES

    OpenAIRE

    Matsuoka, R; Asonuma, K.; Takahashi, G; Danjo, T.; Hirana, K.

    2012-01-01

    This paper reports an experiment conducted to evaluate correction methods of chromatic aberrations in images acquired by a nonmetric digital camera. The chromatic aberration correction methods evaluated in the experiment are classified into two kinds. One is the method to correct image coordinates by using camera calibration results of color-separated images. The other is the method based on the assumption that the magnitude of chromatic aberrations can be expressed by a function of ...

  3. Spherical aberration from trajectories in real and hard-edge solenoid fields

    Indian Academy of Sciences (India)

    BISWAS B

    2016-06-01

    For analytical, real and hard-edge solenoidal axial magnetic fields, the low-energy electron trajectories are obtained using the third-order paraxial ray equation. Using the particle trajectories, it is shown that the spherical aberration in the hard-edge model is high and it increases monotonously with hard edginess, although the focal length converges, in agreement with a recentfield and spherical aberration model. The model paved the way for a hard-edge approximation that gives correct focal length and spherical aberration, which is verified here by the trajectory method. In essence, we show that exact hard-edge fields give infinite spherical aberrations.

  4. Preferential entry of botulinum neurotoxin A Hc domain through intestinal crypt cells and targeting to cholinergic neurons of the mouse intestine.

    Directory of Open Access Journals (Sweden)

    Aurélie Couesnon

    Full Text Available Botulism, characterized by flaccid paralysis, commonly results from botulinum neurotoxin (BoNT absorption across the epithelial barrier from the digestive tract and then dissemination through the blood circulation to target autonomic and motor nerve terminals. The trafficking pathway of BoNT/A passage through the intestinal barrier is not yet fully understood. We report that intralumenal administration of purified BoNT/A into mouse ileum segment impaired spontaneous muscle contractions and abolished the smooth muscle contractions evoked by electric field stimulation. Entry of BoNT/A into the mouse upper small intestine was monitored with fluorescent HcA (half C-terminal domain of heavy chain which interacts with cell surface receptor(s. We show that HcA preferentially recognizes a subset of neuroendocrine intestinal crypt cells, which probably represent the entry site of the toxin through the intestinal barrier, then targets specific neurons in the submucosa and later (90-120 min in the musculosa. HcA mainly binds to certain cholinergic neurons of both submucosal and myenteric plexuses, but also recognizes, although to a lower extent, other neuronal cells including glutamatergic and serotoninergic neurons in the submucosa. Intestinal cholinergic neuron targeting by HcA could account for the inhibition of intestinal peristaltism and secretion observed in botulism, but the consequences of the targeting to non-cholinergic neurons remains to be determined.

  5. Chromosomal aberrations related to metastasis of human solid tumors

    Institute of Scientific and Technical Information of China (English)

    Lun-Xiu Qin

    2002-01-01

    The central role of sequential accumulation of genetic alterations during the development of cancer has been firmly established since the pioneering cytogenetic studies successfully defined recurrent chromosome changes in spedfic types of tumor. In the course of carcinogenesis, cells experience several genetic alterations that are associated with the transition from a preneoplastic lesion to an invasive tumor and finally to the metastatic state. Tumor progression is characterized by stepwise accumulation of genetic alterations.So does the dominant metastatic clone. Modern molecular genetic analyses have clarified that genomic changes accumulate during the development and progression of cancers. In comparison with the corresponding primary tumor,additional events of chromosomal aberrations (including gains or allelic losses) are frequently found in metastases, and the incidence of combined chromosomal alterations in the primary tumor, plus the occurrence of additional aberrations inthe distant metastases, correlated significantly with decreased postmetastatic survival. The deletions at 3p, 4p, 6q, 8p, 10q,11p, 11q, 12p, 13q, 16q, 17p, 18q, 21q, and 22q, as well as the over-representations at 1q, 8q, 9q, 14q and 15q, have been found to associate preferentially with the metastatic phenotype of human cancers. Among of them, the deletions on chromosomes 8p, 17p, 11p and 13p seem to be more significant, and more detail fine regions of them, including 8p11, 8p21-12, 8p22, 8p23, 17p13.3, 11p15.5, and 13q12-13 have been suggested harboring metastasis-suppressor genes.During the past decade, several human chromosomes have been functionally tested through the use of microcell-mediated chromosome transfer (MMCT), and metastasis-suppressor activities have been reported on chromosomes 1, 6, 7, 8, 10,11, 12, 16, and 17. However, it is not actually known at what stage of the metastatic cascade these alterations have occurred.There is still controversial with the association

  6. Refractive and diffractive neutron optics with reduced chromatic aberration

    DEFF Research Database (Denmark)

    Poulsen, Stefan Othmar; Poulsen, Henning Friis; Bentley, P.M.

    2014-01-01

    by the use of optics for focusing and imaging. Refractive and diffractive optical elements, e.g. compound refractive lenses and Fresnel zone plates, are attractive due to their low cost, and simple alignment. These optical elements, however, suffer from chromatic aberration, which limit their effectiveness...... to highly monochromatic beams. This paper presents two novel concepts for focusing and imaging non-monochromatic thermal neutron beams with well-known optical elements: (1) a fast mechanical transfocator based on a compound refractive lens, which actively varies the number of individual lenses in the beam...... path to focus and image a time-of-flight beam, and (2) a passive optical element consisting of a compound refractive lens, and a Fresnel zone plate, which may focus and image both continuous and pulsed neutron beams....

  7. Environmental Transmission Electron Microscopy in an Aberration-Corrected Environment

    DEFF Research Database (Denmark)

    Hansen, Thomas W.; Wagner, Jakob B.

    2012-01-01

    The increasing use of environmental transmission electron microscopy (ETEM) in materials science provides exciting new possibilities for investigating chemical reactions and understanding both the interaction of fast electrons with gas molecules and the effect of the presence of gas on high......-resolution imaging. A gaseous atmosphere in the pole-piece gap of the objective lens of the microscope alters both the incoming electron wave prior to interaction with the sample and the outgoing wave below the sample. Whereas conventional TEM samples are usually thin (below 100 nm), the gas in the environmental...... cell fills the entire gap between the pole pieces and is thus not spatially localized. By using an FEI Titan environmental transmission electron microscope equipped with a monochromator and an aberration corrector on the objective lens, we have investigated the effects on imaging and spectroscopy...

  8. Biological dosimetry of ionizing radiation by chromosomal aberration analysis

    International Nuclear Information System (INIS)

    Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haematological, biochemical, and cytogenetic data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable. In this case, the study ol chromosomal aberrations, normally dicentric chromosomes, in peripheral lymphocytes can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve, using dicentric chromosomes analysis, X-rays at 300 kVp, 114 rad/min and temperature 37 degree celsius has been produced. Experimental data is fitted to model Y =α + β1D + β2D 2 , where Y is the number of dicentrics per cell and D the dose. The curve is compared with those produced elsewhere. (Author) 14 refs

  9. Studying Atomic Structures by Aberration-Corrected Transmission Electron Microscopy

    Science.gov (United States)

    Urban, Knut W.

    2008-07-01

    Seventy-five years after its invention, transmission electron microscopy has taken a great step forward with the introduction of aberration-corrected electron optics. An entirely new generation of instruments enables studies in condensed-matter physics and materials science to be performed at atomic-scale resolution. These new possibilities are meeting the growing demand of nanosciences and nanotechnology for the atomic-scale characterization of materials, nanosynthesized products and devices, and the validation of expected functions. Equipped with electron-energy filters and electron-energy loss spectrometers, the new instruments allow studies not only of structure but also of elemental composition and chemical bonding. The energy resolution is about 100 milli electron volts, and the accuracy of spatial measurements has reached a few picometers. However, understanding the results is generally not straightforward and only possible with extensive quantum-mechanical computer calculations.

  10. Relativistic stellar aberration for the Space Interferometry Mission

    CERN Document Server

    Turyshev, S G

    2002-01-01

    This paper analyses the relativistic stellar aberration requirements for the Space Interferometry Mission (SIM). We address the issue of general relativistic deflection of light by the massive self-gravitating bodies. Specifically, we present estimates for corresponding deflection angles due to the monopole components of the gravitational fields of a large number of celestial bodies in the solar system. We study the possibility of deriving an additional navigational constraints from the need to correct for the gravitational bending of light that is traversing the solar system. It turns out that positions of the outer planets presently may not have a sufficient accuracy for the precision astrometry. However, SIM may significantly improve those simply as a by-product of its astrometric program. We also consider influence of the higher gravitational multipoles, notably the quadrupole and the octupole ones, on the gravitational bending of light. Thus, one will have to model and account for their influence while o...

  11. Propagation of Aberrations through Phase Induced Amplitude Apodization coronagraph

    CERN Document Server

    Pueyo, Laurent; Shaklan, Stuart; 10.1364/JOSAA.28.000189

    2011-01-01

    The specification of polishing requirements for the optics in coronagraphs dedicated to exo-planet detection requires careful and accurate optical modelling. Numerical representations of the propagation of aberrations through the system as well as simulations of the broadband wavefront compensation system using multiple DMs are critical when one devises an error budget for such a class of instruments. In this communication we introduce an analytical tool that serves this purpose for Phase Induced Amplitude Apodisation (PIAA) coronagraphs. We first start by deriving the analytical form of the propagation of a harmonic ripple through a PIAA unit. Using this result we derive the chromaticity of the field at any plane in the optical train of a telescope equipped with such a coronagraph. Finally we study the chromatic response of a sequential DM wavefront actuator correcting such a corrugated field and thus quantify the requirements on the manufacturing of PIAA mirrors

  12. Chromosomal aberration frequency in lymphocytes predicts the risk of cancer

    DEFF Research Database (Denmark)

    Bonassi, Stefano; Norppa, Hannu; Ceppi, Marcello;

    2008-01-01

    incidence and/or mortality for an average of 10.1 years; 368 cancer deaths and 675 incident cancer cases were observed. Subjects were classified within each laboratory according to tertiles of CA frequency. The relative risk (RR) of cancer was increased for subjects in the medium [RR = 1.31, 95% confidence...... for stomach cancer [RR(medium) = 1.17 (95% CI = 0.37-3.70), RR(high) = 3.13 (95% CI = 1.17-8.39)]. Exposure to carcinogens did not modify the effect of CA levels on overall cancer risk. These results reinforce the evidence of a link between CA frequency and cancer risk and provide novel information......Mechanistic evidence linking chromosomal aberration (CA) to early stages of cancer has been recently supported by the results of epidemiological studies that associated CA frequency in peripheral lymphocytes of healthy individuals to future cancer incidence. To overcome the limitations of single...

  13. The Oncoprotein BRD4-NUT Generates Aberrant Histone Modification Patterns

    Science.gov (United States)

    Zee, Barry M.; Dibona, Amy B.; Alekseyenko, Artyom A.; French, Christopher A.; Kuroda, Mitzi I.

    2016-01-01

    Defects in chromatin proteins frequently manifest in diseases. A striking case of a chromatin-centric disease is NUT-midline carcinoma (NMC), which is characterized by expression of NUT as a fusion partner most frequently with BRD4. ChIP-sequencing studies from NMC patients revealed that BRD4-NUT (B4N) covers large genomic regions and elevates transcription within these domains. To investigate how B4N modulates chromatin, we performed affinity purification of B4N when ectopically expressed in 293-TREx cells and quantified the associated histone posttranslational modifications (PTM) using proteomics. We observed significant enrichment of acetylation particularly on H3 K18 and of combinatorial patterns such as H3 K27 acetylation paired with K36 methylation. We postulate that B4N complexes override the preexisting histone code with new PTM patterns that reflect aberrant transcription and that epigenetically modulate the nucleosome environment toward the NMC state. PMID:27698495

  14. Aberrantly methylated DNA as a biomarker in breast cancer

    DEFF Research Database (Denmark)

    Kristiansen, Søren; Jørgensen, Lars Mønster; Guldberg, Per;

    2013-01-01

    hypermethylation events, their use as tumor biomarkers is usually not hampered by analytical signals from normal cells, which is a general problem for existing protein tumor markers used for clinical assessment of breast cancer. There is accumulating evidence that DNA-methylation changes in breast cancer patients......Aberrant DNA hypermethylation at gene promoters is a frequent event in human breast cancer. Recent genome-wide studies have identified hundreds of genes that exhibit differential methylation between breast cancer cells and normal breast tissue. Due to the tumor-specific nature of DNA...... occur early during tumorigenesis. This may open up for effective screening, and analysis of blood or nipple aspirate may later help in diagnosing breast cancer. As a more detailed molecular characterization of different types of breast cancer becomes available, the ability to divide patients into...

  15. Genomic aberrations frequently alter chromatin regulatory genes in chordoma.

    Science.gov (United States)

    Wang, Lu; Zehir, Ahmet; Nafa, Khedoudja; Zhou, Nengyi; Berger, Michael F; Casanova, Jacklyn; Sadowska, Justyna; Lu, Chao; Allis, C David; Gounder, Mrinal; Chandhanayingyong, Chandhanarat; Ladanyi, Marc; Boland, Patrick J; Hameed, Meera

    2016-07-01

    Chordoma is a rare primary bone neoplasm that is resistant to standard chemotherapies. Despite aggressive surgical management, local recurrence and metastasis is not uncommon. To identify the specific genetic aberrations that play key roles in chordoma pathogenesis, we utilized a genome-wide high-resolution SNP-array and next generation sequencing (NGS)-based molecular profiling platform to study 24 patient samples with typical histopathologic features of chordoma. Matching normal tissues were available for 16 samples. SNP-array analysis revealed nonrandom copy number losses across the genome, frequently involving 3, 9p, 1p, 14, 10, and 13. In contrast, copy number gain is uncommon in chordomas. Two minimum deleted regions were observed on 3p within a ∼8 Mb segment at 3p21.1-p21.31, which overlaps SETD2, BAP1 and PBRM1. The minimum deleted region on 9p was mapped to CDKN2A locus at 9p21.3, and homozygous deletion of CDKN2A was detected in 5/22 chordomas (∼23%). NGS-based molecular profiling demonstrated an extremely low level of mutation rate in chordomas, with an average of 0.5 mutations per sample for the 16 cases with matched normal. When the mutated genes were grouped based on molecular functions, many of the mutation events (∼40%) were found in chromatin regulatory genes. The combined copy number and mutation profiling revealed that SETD2 is the single gene affected most frequently in chordomas, either by deletion or by mutations. Our study demonstrated that chordoma belongs to the C-class (copy number changes) tumors whose oncogenic signature is non-random multiple copy number losses across the genome and genomic aberrations frequently alter chromatin regulatory genes. © 2016 Wiley Periodicals, Inc.

  16. Anti-topoisomerase drugs as potent inducers of chromosomal aberrations

    Directory of Open Access Journals (Sweden)

    Loredana Bassi

    2000-12-01

    Full Text Available DNA topoisomerases catalyze topological changes in DNA that are essential for normal cell cycle progression and therefore they are a preferential target for the development of anticancer drugs. Anti-topoisomerase drugs can be divided into two main classes: "cleavable complex" poisons and catalytic inhibitors. The "cleavable complex" poisons are very effective as anticancer drugs but are also potent inducers of chromosome aberrations so they can cause secondary malignancies. Catalytic inhibitors are cytotoxic but they do not induce chromosome aberrations. Knowledge about the mechanism of action of topoisomerase inhibitors is important to determine the best anti-topoisomerase combinations, with a reduced risk of induction of secondary malignancies.As topoisomerases de DNA catalisam alterações topológicas no DNA que são essenciais para a progressão do ciclo celular normal e, portanto, são um alvo preferencial para o desenvolvimento de drogas anticâncer. Drogas anti-topoisomerases podem ser divididas em duas classes principais: drogas anti-"complexos cliváveis" e inibidores catalíticos. As drogas anti-"complexos cliváveis" são muito eficazes como drogas anticancerígenas, mas são também potentes indutores de aberrações cromossômicas, podendo causar neoplasias malignas secundárias. Inibidores catalíticos são citotóxicos mas não induzem aberrações cromossômicas. Conhecimento a respeito do mecanismo de ação de inibidores de topoisomerases é importante para determinar as melhores combinações anti-topoisomerases, com um reduzido risco de indução de neoplasias malignas secundárias.

  17. Longitudinal trajectories of aberrant behavior in fragile X syndrome.

    Science.gov (United States)

    Hustyi, Kristin M; Hall, Scott S; Jo, Booil; Lightbody, Amy A; Reiss, Allan L

    2014-11-01

    The Aberrant Behavior Checklist-Community (ABC-C; Aman et al., 1995) has been increasingly adopted as a primary tool for measuring behavioral change in clinical trials for individuals with fragile X syndrome (FXS). To our knowledge, however, no study has documented the longitudinal trajectory of aberrant behaviors in individuals with FXS using the ABC-C. As part of a larger longitudinal study, we examined scores obtained on the ABC-C subscales for 124 children and adolescents (64 males, 60 females) with FXS who had two or more assessments (average interval between assessments was approximately 4 years). Concomitant changes in age-equivalent scores on the Vineland Adaptive Behavior Scales (VABS) were also examined. As expected for an X-linked genetic disorder, males with FXS obtained significantly higher scores on all subscales of the ABC-C and significantly lower age-equivalent scores on the VABS than females with FXS. In both males and females with FXS, scores on the Irritability/Agitation and Hyperactivity/Noncompliance subscales of the ABC-C decreased significantly with age, with little to no change occurring over time on the Lethargy/Social Withdrawal, Stereotypic Behavior, and Inappropriate Speech subscales. The decrease in scores on the Hyperactivity/Noncompliance domain was significantly greater for males than for females. In both males and females, age-equivalent scores on the VABS increased significantly over this developmental period. These results establish a basis upon which to evaluate long-term outcomes from intervention-based research. However, longitudinal direct observational studies are needed to establish whether the severity of problem behavior actually decreases over time in this population.

  18. Genomic aberrations frequently alter chromatin regulatory genes in chordoma.

    Science.gov (United States)

    Wang, Lu; Zehir, Ahmet; Nafa, Khedoudja; Zhou, Nengyi; Berger, Michael F; Casanova, Jacklyn; Sadowska, Justyna; Lu, Chao; Allis, C David; Gounder, Mrinal; Chandhanayingyong, Chandhanarat; Ladanyi, Marc; Boland, Patrick J; Hameed, Meera

    2016-07-01

    Chordoma is a rare primary bone neoplasm that is resistant to standard chemotherapies. Despite aggressive surgical management, local recurrence and metastasis is not uncommon. To identify the specific genetic aberrations that play key roles in chordoma pathogenesis, we utilized a genome-wide high-resolution SNP-array and next generation sequencing (NGS)-based molecular profiling platform to study 24 patient samples with typical histopathologic features of chordoma. Matching normal tissues were available for 16 samples. SNP-array analysis revealed nonrandom copy number losses across the genome, frequently involving 3, 9p, 1p, 14, 10, and 13. In contrast, copy number gain is uncommon in chordomas. Two minimum deleted regions were observed on 3p within a ∼8 Mb segment at 3p21.1-p21.31, which overlaps SETD2, BAP1 and PBRM1. The minimum deleted region on 9p was mapped to CDKN2A locus at 9p21.3, and homozygous deletion of CDKN2A was detected in 5/22 chordomas (∼23%). NGS-based molecular profiling demonstrated an extremely low level of mutation rate in chordomas, with an average of 0.5 mutations per sample for the 16 cases with matched normal. When the mutated genes were grouped based on molecular functions, many of the mutation events (∼40%) were found in chromatin regulatory genes. The combined copy number and mutation profiling revealed that SETD2 is the single gene affected most frequently in chordomas, either by deletion or by mutations. Our study demonstrated that chordoma belongs to the C-class (copy number changes) tumors whose oncogenic signature is non-random multiple copy number losses across the genome and genomic aberrations frequently alter chromatin regulatory genes. © 2016 Wiley Periodicals, Inc. PMID:27072194

  19. Aberrant meiotic behavior in Agave tequilana Weber var. azul

    Directory of Open Access Journals (Sweden)

    Rodríguez-Garay Benjamin

    2002-10-01

    Full Text Available Abstract Background Agave tequilana Weber var. azul, is the only one variety permitted by federal law in México to be used for tequila production which is the most popular contemporary alcoholic beverage made from agave and recognized worldwide. Despite the economic, genetic, and ornamental value of the plant, it has not been subjected to detailed cytogenetic research, which could lead to a better understanding of its reproduction for future genetic improvement. The objective of this work was to study the meiotic behavior in pollen mother cells and its implications on the pollen viability in Agave tequilana Weber var. azul. Results The analysis of Pollen Mother Cells in anaphase I (A-I showed 82.56% of cells with a normal anaphase and, 17.44% with an irregular anaphase. In which 5.28% corresponded to cells with side arm bridges (SAB; 3.68% cells with one bridge and one fragment; 2.58% of irregular anaphase showed cells with one or two lagging chromosomes and 2.95% showed one acentric fragment; cells with two bridges and cells with two bridges and one acentric fragment were observed in frequencies of 1.60% and 1.35% respectively. In anaphase II some cells showed bridges and fragments too. Aberrant A-I cells had many shrunken or empty pollen grains (42.00% and 58.00 % viable pollen. Conclusion The observed meiotic irregularities suggest that structural chromosome aberrations have occurred, such as heterozygous inversions, sister chromatid exchanges, deletions and duplications which in turn are reflected in a low pollen viability.

  20. Genomic Aberrations Frequently Alter Chromatin Regulatory Genes in Chordoma

    Science.gov (United States)

    Wang, Lu; Zehir, Ahmet; Nafa, Khedoudja; Zhou, Nengyi; Berger, Michael F.; Casanova, Jacklyn; Sadowska, Justyna; Lu, Chao; Allis, C. David; Gounder, Mrinal; Chandhanayingyong, Chandhanarat; Ladanyi, Marc; Boland, Patrick J; Hameed, Meera

    2016-01-01

    Chordoma is a rare primary bone neoplasm that is resistant to standard chemotherapies. Despite aggressive surgical management, local recurrence and metastasis is not uncommon. To identify the specific genetic aberrations that play key roles in chordoma pathogenesis, we utilized a genome-wide high-resolution SNP-array and next generation sequencing (NGS)-based molecular profiling platform to study 24 patient samples with typical histopathologic features of chordoma. Matching normal tissues were available for 16 samples. SNP-array analysis revealed nonrandom copy number losses across the genome, frequently involving 3, 9p, 1p, 14, 10, and 13. In contrast, copy number gain is uncommon in chordomas. Two minimum deleted regions were observed on 3p within a ~8 Mb segment at 3p21.1–p21.31, which overlaps SETD2, BAP1 and PBRM1. The minimum deleted region on 9p was mapped to CDKN2A locus at 9p21.3, and homozygous deletion of CDKN2A was detected in 5/22 chordomas (~23%). NGS-based molecular profiling demonstrated an extremely low level of mutation rate in chordomas, with an average of 0.5 mutations per sample for the 16 cases with matched normal. When the mutated genes were grouped based on molecular functions, many of the mutation events (~40%) were found in chromatin regulatory genes. The combined copy number and mutation profiling revealed that SETD2 is the single gene affected most frequently in chordomas, either by deletion or by mutations. Our study demonstrated that chordoma belongs to the C-class (copy number changes) tumors whose oncogenic signature is non-random multiple copy number losses across the genome and genomic aberrations frequently alter chromatin regulatory genes. PMID:27072194

  1. Prostate cancer, prostate cancer death, and death from other causes, among men with metabolic aberrations.

    OpenAIRE

    Häggström, Christel; Stocks, Tanja; Nagel, Gabriele; Manjer, Jonas; Bjørge, Tone; Hallmans, Göran; Engeland, Anders; Ulmer, Hanno; Lindkvist, Björn; Selmer, Randi; Concin, Hans; Tretli, Steinar; Jonsson, Håkan; Stattin, Pär

    2014-01-01

    Few previous studies of metabolic aberrations and prostate cancer risk have taken into account the fact that men with metabolic aberrations have an increased risk of death from causes other than prostate cancer. The aim of this study was to calculate, in a real-life scenario, the risk of prostate cancer diagnosis, prostate cancer death, and death from other causes.

  2. A case of valvular pulmonic stenosis and an aberrant coronary artery in a Brittany spaniel.

    Science.gov (United States)

    Estey, Chelsie

    2011-05-01

    Valvular pulmonic stenosis and aberrancy of the right coronary artery with subsequent subvalvular stenosis was found on echocardiographic evaluation of a 9-month-old Brittany spaniel. Previous echocardiography at 4 mo of age revealed the pulmonic stenosis; however, the aberrant coronary artery only became apparent during the second evaluation.

  3. Numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana

    OpenAIRE

    Ji, X.

    2014-01-01

    Numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana. I studied numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana. The large genomic changes are important for gene balance control, gene expression and regulation, and may affect the plant’s phenotype. Moreover, chromosome changes, in particular polyploidy, inversions and translocations play a signif...

  4. Combining Noncontingent Reinforcement and Differential Reinforcement Schedules as Treatment for Aberrant Behavior.

    Science.gov (United States)

    Marcus, Bethany A.; Vollmer, Timothy R.

    1996-01-01

    In this study with three children (ages four and five) with severe developmental disabilities and aberrant behavior maintained by tangible positive reinforcement, noncontingent reinforcement, and differential reinforcement of alternative behavior were found to decrease the frequency of aberrant behavior while strengthening mands. (Author/DB)

  5. Cancer biomarkers defined by autoantibody signatures to aberrant O-glycopeptide epitopes

    DEFF Research Database (Denmark)

    Wandall, Hans H; Blixt, Ola; Tarp, Mads A;

    2010-01-01

    -glycopeptide microarray was developed that detected IgG antibodies to aberrant O-glycopeptide epitopes in patients vaccinated with a keyhole limpet hemocyanin-conjugated truncated MUC1 peptide. We detected cancer-associated IgG autoantibodies in sera from breast, ovarian, and prostate cancer patients against different...... evaluated whether autoantibodies generated to aberrant O-glycoforms of MUC1 might serve as sensitive diagnostic biomarkers for cancer. Using an antibody-based glycoprofiling ELISA assay, we documented that aberrant truncated glycoforms were not detected in sera of cancer patients. An O......Autoantibodies to cancer antigens hold promise as biomarkers for early detection of cancer. Proteins that are aberrantly processed in cancer cells are likely to present autoantibody targets. The extracellular mucin MUC1 is overexpressed and aberrantly glycosylated in many cancers; thus, we...

  6. Influence of wave-front aberrations on bit error rate in inter-satellite laser communications

    Science.gov (United States)

    Yang, Yuqiang; Han, Qiqi; Tan, Liying; Ma, Jing; Yu, Siyuan; Yan, Zhibin; Yu, Jianjie; Zhao, Sheng

    2011-06-01

    We derive the bit error rate (BER) of inter-satellite laser communication (lasercom) links with on-off-keying systems in the presence of both wave-front aberrations and pointing error, but without considering the noise of the detector. Wave-front aberrations induced by receiver terminal have no influence on the BER, while wave-front aberrations induced by transmitter terminal will increase the BER. The BER depends on the area S which is truncated out by the threshold intensity of the detector (such as APD) on the intensity function in the receiver plane, and changes with root mean square (RMS) of wave-front aberrations. Numerical results show that the BER rises with the increasing of RMS value. The influences of Astigmatism, Coma, Curvature and Spherical aberration on the BER are compared. This work can benefit the design of lasercom system.

  7. Chromosomal aberration analysis of persons occupationally exposed to radiation in Iran (2)

    International Nuclear Information System (INIS)

    The results of chromosome aberration analysis on lymphocytes from 333 persons suspected of being overexposed to X and gamma rays in recent years at Iran is presented. 91 persons were associated with industrial radiography, 124 with radiology and 118 with medical research and therapy centers. The total yields of chromosome aberration per 100 cells were respectively 3.76, 2.92 and 2.96. The frequencies of dicentrics which are important in biological dosimetry were respectively 0.18, 0.17 and 0.21. In this investigation, 50 subjects were also examined as control with a mean aberration of 1.14 per 100 cells. With regard to incidence of chromosome aberrations as mentioned, the rate of chromosome aberrations in industrial radiographers was the most significant

  8. Vision improvement by correcting higher-order aberrations with customized soft contact lenses in keratoconic eyes

    Science.gov (United States)

    Sabesan, Ramkumar; Jeong, Tae Moon; Carvalho, Luis; Cox, Ian G.; Williams, David R.; Yoon, Geunyoung

    2007-04-01

    Higher-order aberration correction in abnormal eyes can result in significant vision improvement, especially in eyes with abnormal corneas. Customized optics such as phase plates and customized contact lenses are one of the most practical, nonsurgical ways to correct these ocular higher-order aberrations. We demonstrate the feasibility of correcting higher-order aberrations and improving visual performance with customized soft contact lenses in keratoconic eyes while compensating for the static decentration and rotation of the lens. A reduction of higher-order aberrations by a factor of 3 on average was obtained in these eyes. The higher-order aberration correction resulted in an average improvement of 2.1 lines in visual acuity over the conventional correction of defocus and astigmatism alone.

  9. Correlation between Post-LASIK Starburst Symptom and Ocular Wavefront Aberrations

    Institute of Scientific and Technical Information of China (English)

    LIU Yong-Ji; MU Guo-Guang; WANG Zhao-Qi; WANG Yan

    2006-01-01

    Monochromatic aberrations in post laser in-situ keratomileusis (LASIK) eyes are measured. The data are categorized into reference group and starburst group according to the visual symptoms. Statistic analysis has been made to find the correJation between the ocular wavefront aberrations and the starburst symptom. The rms aberrations of the 3rd and 4th orders for the starburst group are significantly larger than those for the reference group. The starburst symptom shows a strong correlation with vertical coma, total coma, spherical aberrations. For 3-mm pupil size and 5.8-mm pupil size, the modulation transfer function (MTF) of the starburst group are lower than those of the reference group, but their visual acuities are close. MTF and PSF analyses are made for two groups, and the results are consistent with the statistical analysis, which means the difference between the two groups is mainly due to the third- and fourth-order Zernike aberrations.

  10. Transitionality in addiction: A "temporal continuum" hypotheses involving the aberrant motivation, the hedonic dysregulation, and the aberrant learning.

    Science.gov (United States)

    Patrono, Enrico; Gasbarri, Antonella; Tomaz, Carlos; Nishijo, Hisao

    2016-08-01

    Addiction is a chronic compulsion and relapsing disorder. It involves several brain areas and circuits, which encode vary functions such as reward, motivation, and memory. Drug addiction is defined as a "pathological pattern of use of a substance", characterized by the loss of control on drug-taking-related behaviors, the pursuance of those behaviors even in the presence of negative consequences, and a strong motivated activity to assume substances. Three different theories guide experimental research on drug addiction. Each of these theories consider singles features, such as an aberrant motivation, a hedonic dysregulation, and an aberrant habit learning as the main actor to explain the entire process of the addictive behaviors. The major goal of this study is to present a new hypotheses of transitionality from a controlled use to abuse of addictive substances trough the overview of the three different theories, considering all the single features of each single theory together on the same "temporal continuum" from use to abuse of addictive substances. Recently, it has been suggested that common neural systems may be activated by natural and pharmacological stimuli, raising the hypotheses that binge-eating disorders could be considered as addictive behaviors. The second goal of this study is to present evidences in order to highlight a possible psycho-bio-physiological superimposition between drug and "food addiction". Finally, interesting questions are brought up starting from last findings about a theoretical/psycho-bio-physiological superimposition between drug and "food addiction" and their possibly same transitionality along the same "temporal continuum" from use to abuse of addictive substances in order to investigate new therapeutic strategies based on new therapeutic strategies based on the individual moments characterizing the transition from the voluntary intake of substances to the maladaptive addictive behavior. PMID:27372858

  11. Aberrant expressions of c-KIT and DOG-1 in mucinous and nonmucinous colorectal carcinomas and relation to clinicopathologic features and prognosis.

    Science.gov (United States)

    Foda, Abd Al-Rahman Mohammad; Mohamed, Mie Ali

    2015-10-01

    c-KIT and DOG-1 are 2 highly expressed proteins in gastrointestinal stromal tumors. Few studies had investigated c-KIT, but not DOG-1, expression in colorectal carcinoma (CRC). This study aims to investigate expressions of c-KIT and DOG-1 in colorectal mucinous carcinoma and nonmucinous carcinoma using manual tissue microarray technique. In this work, we studied tumor tissue specimens from 150 patients with colorectal mucinous (MA) and nonmucinous adenocarcinoma (NMA). High-density manual tissue microarrays were constructed using modified mechanical pencil tip technique, and immunohistochemistry for c-KIT and DOG-1 was done. We found that aberrant c-KIT expression was detected in 12 cases (8%); 6 cases (4%) showed strong expression. Aberrant DOG-1 expression was detected in 15 cases (10%); among them, only 4 cases (2.7%) showed strong expression. Nonmucinous adenocarcinoma showed a significantly high expression of c-KIT, but not DOG-1, than MA. Aberrant c-KIT and DOG-1 expressions were significantly unrelated but were associated with excessive microscopic abscess formation. Neither c-KIT nor DOG-1 expression showed a significant impact on disease-free survival or overall survival. In conclusion, aberrant c-KIT and DOG-1 expressions in CRC are rare events, either in NMA or MA. Nonmucinous adenocarcinoma showed a significantly higher expression of c-KIT, but not DOG-1, than MA. The expressions of both in CRC are significantly unrelated but are associated with microscopic abscess formation. Neither c-KIT nor DOG-1 expression showed a significant impact on disease-free survival or overall survival. So, c-KIT and DOG-1 immunostaining is not a cost-effective method of identifying patients with CRC who may benefit from treatment with tyrosine kinase inhibitors. PMID:26272691

  12. Splicing aberrations caused by constitutional RB1 gene mutations in retinoblastoma

    Indian Academy of Sciences (India)

    Vidya Latha Parsam; Mohammed Javed Ali; Santosh G Honavar; Geeta K Vemuganti; Chitra Kannabiran

    2011-06-01

    Analysis of RB1 mRNA from blood leukocytes of patients with retinoblastoma identified the effects of mutations involving consensus splice site, exonic substitution and whole-exon deletions identified in genomic DNA of these patients. In addition, this study identified mutations in cases in which no mutations were detectable in the genomic DNA. One proband had mutation at the canonical splice site at +5 position of IVS22, and analysis of the transcripts in this family revealed skipping of exon 22 in three members of this family. In one proband, a missense substitution of c.652T > G (g.56897T > G; Leu218Val) in exon 7 led to splicing aberrations involving deletions of exons 7 and 8, suggesting the formation of a cryptic splice site. In two probands with no detectable changes in the genomic DNA upon screening of RB1 exons and flanking intronic sequences, transcripts were found to have deletions of exon 6 in one, and exons 21 and 22 in another family. In two probands, RNA analysis confirmed genomic deletions involving one or more exons. This study reveals novel effects of RB1 mutations on splicing and suggests the utility of RNA analysis as an adjunct to mutational screening of genomic DNA in retinoblastoma.

  13. Opening of the TAR hairpin in the HIV-1 genome causes aberrant RNA dimerization and packaging

    Directory of Open Access Journals (Sweden)

    Das Atze T

    2012-07-01

    Full Text Available Abstract Background The TAR hairpin is present at both the 5′ and 3′ end of the HIV-1 RNA genome. The 5′ element binds the viral Tat protein and is essential for Tat-mediated activation of transcription. We recently observed that complete TAR deletion is allowed in the context of an HIV-1 variant that does not depend on this Tat-TAR axis for transcription. Mutations that open the 5′ stem-loop structure did however affect the leader RNA conformation and resulted in a severe replication defect. In this study, we set out to analyze which step of the HIV-1 replication cycle is affected by this conformational change of the leader RNA. Results We demonstrate that opening the 5′ TAR structure through a deletion in either side of the stem region caused aberrant dimerization and reduced packaging of the unspliced viral RNA genome. In contrast, truncation of the TAR hairpin through deletions in both sides of the stem did not affect RNA dimer formation and packaging. Conclusions These results demonstrate that, although the TAR hairpin is not essential for RNA dimerization and packaging, mutations in TAR can significantly affect these processes through misfolding of the relevant RNA signals.

  14. Genotoxicity evaluation of dental restoration nanocomposite using comet assay and chromosome aberration test

    Science.gov (United States)

    Musa, Marahaini; Thirumulu Ponnuraj, Kannan; Mohamad, Dasmawati; Rahman, Ismail Ab

    2013-01-01

    Nanocomposite is used as a dental filling to restore the affected tooth, especially in dental caries. The dental nanocomposite (KelFil) for tooth restoration used in this study was produced by the School of Dental Sciences, Universiti Sains Malaysia, Malaysia and is incorporated with monodispersed, spherical nanosilica fillers. The aim of the study was to determine the genotoxic effect of KelFil using in vitro genotoxicity tests. The cytotoxicity and genotoxicity of KelFil was evaluated using MTT assay, comet assay and chromosome aberration tests with or without the addition of a metabolic activation system (S9 mix), using the human lung fibroblast cell line (MRC-5). Concurrent negative and positive controls were included. In the comet assay, no comet formation was found in the KelFil groups. There was a significant difference in tail moment between KelFil groups and positive control (p dental restoration nanocomposite (KelFil) is non-genotoxic under the present test conditions.

  15. Aberrant herpesvirus-induced polyadenylation correlates with cellular messenger RNA destruction.

    Directory of Open Access Journals (Sweden)

    Yeon J Lee

    2009-05-01

    Full Text Available Regulation of messenger RNA (mRNA stability plays critical roles in controlling gene expression, ensuring transcript fidelity, and allowing cells to respond to environmental cues. Unregulated enhancement of mRNA turnover could therefore dampen cellular responses to such signals. Indeed, several herpesviruses instigate widespread destruction of cellular mRNAs to block host gene expression and evade immune detection. Kaposi's sarcoma-associated herpesvirus (KSHV promotes this phenotype via the activity of its viral SOX protein, although the mechanism of SOX-induced mRNA turnover has remained unknown, given its apparent lack of intrinsic ribonuclease activity. Here, we report that KSHV SOX stimulates cellular transcriptome turnover via a unique mechanism involving aberrant polyadenylation. Transcripts in SOX-expressing cells exhibit extended poly(A polymerase II-generated poly(A tails and polyadenylation-linked mRNA turnover. SOX-induced polyadenylation changes correlate with its RNA turnover function, and inhibition of poly(A tail formation blocks SOX activity. Both nuclear and cytoplasmic poly(A binding proteins are critical cellular cofactors for SOX function, the latter of which undergoes striking nuclear relocalization by SOX. SOX-induced mRNA turnover therefore represents both a novel mechanism of host shutoff as well as a new model system to probe the regulation of poly(A tail-stimulated mRNA turnover in mammalian cells.

  16. Micronuclei versus Chromosomal Aberrations Induced by X-Ray in Radiosensitive Mammalian Cells.

    Directory of Open Access Journals (Sweden)

    Cristina Plamadeala

    2015-03-01

    Full Text Available An experimental study was accomplished to compare estimation methods of ionizing radiations genotoxicity in mammalian cell cultures by means of two cytogenetic parameters with focus on aberrant cells characterized by multiple chromosomal damages.In vitro study was carried out on the genotoxicity of low-medium doses of 190 kV X-rays absorbed in Chinese hamster ovary cell cultures. Micronuclei and ten types of chromosomal aberrations were identified with Giemsa dying and optical microscope screening.The first parameter consisting in micronuclei relative frequency has led to higher linear correlation coefficient than the second one consistent with chromosomal aberrations relative frequency. However, the latter parameter estimated as the sum of all chromosomal aberrations appeared to be more sensitive to radiation dose increasing in the studied dose range, from 0 to 3 Gy. The number of micronuclei occurring simultaneously in a single cell was not higher than 3, while the number of chromosomal aberrations observed in the same cell reached the value of 5 for doses over 1 Gy.Polynomial dose-response curves were evidenced for cells with Ni micronuclei (i=1,3 while non-monotonic curves were evidenced through detailed analysis of aberrant cells with Ni chromosomal changes [Formula: see text] - in concordance with in vitro studies from literature. The investigation could be important for public health issues where micronucleus screening is routinely applied but also for research purposes where various chromosomal aberrations could be of particular interest.

  17. The nonlinear relationship of radiation dose to chromosome aberrations among atomic bomb survivors, Hiroshima and Nagasaki

    International Nuclear Information System (INIS)

    The quantitative relationship of the frequency of cells with radiation-induced chromosome aberrations in peripheral leukocytes in atomic bomb survivors has been evaluated as a function of gamma and neutron doses. Three different models have been examined; each assumes a nonlinear-response to gamma rays and a linear-response to neutrons. From the standpoint of the goodness of fit of these models, the model which ''best'' fits the data of radiation-induced chromosome aberrations is the exponit model, where the frequency of aberrant cells increases exponentially with dose. It is of radiobiological interest that the goodness of fit for this model shows the frequencies of cells with any chromosome aberration or an exchange aberration to be dependent cubically on the gamma ray dose and linearly on the neutron dose. The relative biological effectiveness (RBE) of neutrons is calculated to be 129Dn sup(-2/3) (95% confidence intervals: (121 -- 137)Dn sup(-2/3)) for frequency of cells with any chromosome aberration, and 125Dn sup(-2/3) (95% confidence intervals: (117 -- 132)Dn sup(-2/3)) for the frequency of cells with an exchange aberration where Dn is the neutron dose. (author)

  18. Study on intra-ocular lens aberration measurement in-air

    Science.gov (United States)

    Wang, Yuanyuan; Chen, Jiaojie; Fen, Haihua; Hu, Chuan; Li, Yiyi

    2010-10-01

    In clinical ophthalmology, the wavefront aberration of human eyes is expressed by Zernike polynomial after cataract surgery and intraocular lens implantation, the human eyes aberration will change. The problem of objective evaluation of wavefront aberration introduced by the Intra-ocular (IOL) in-vivo remains unsolved. This paper introduced the measurement principal of IOL wavefront aberration with expression by Zernike polynominal in air. A Hartmann-Shack wavefront sensor system was constructed to measure the wavefront of IOL and to get the corresponding grid patterns. After a series of computer image processing steps, 7th order with 35 items Zernike coefficients was obtained. The IOL of 20.0D power was measured 5 times by this system to get the spherical aberration about 6.73+/-0.02μm, demonstrating the good repeatability of the system. Ten IOLs with the same 20.0D power but difference in surface curvature were chosen for measurement. The spherical aberration observed were in the range of 2.74μm-11.26μm. These results are valuable for the optical design of IOLs and the aberration analysis of human eyes post-operation.

  19. Analysis of nodal aberration properties in off-axis freeform system design.

    Science.gov (United States)

    Shi, Haodong; Jiang, Huilin; Zhang, Xin; Wang, Chao; Liu, Tao

    2016-08-20

    Freeform surfaces have the advantage of balancing off-axis aberration. In this paper, based on the framework of nodal aberration theory (NAT) applied to the coaxial system, the third-order astigmatism and coma wave aberration expressions of an off-axis system with Zernike polynomial surfaces are derived. The relationship between the off-axis and surface shape acting on the nodal distributions is revealed. The nodal aberration properties of the off-axis freeform system are analyzed and validated by using full-field displays (FFDs). It has been demonstrated that adding Zernike terms, up to nine, to the off-axis system modifies the nodal locations, but the field dependence of the third-order aberration does not change. On this basis, an off-axis two-mirror freeform system with 500 mm effective focal length (EFL) and 300 mm entrance pupil diameter (EPD) working in long-wave infrared is designed. The field constant aberrations induced by surface tilting are corrected by selecting specific Zernike terms. The design results show that the nodes of third-order astigmatism and coma move back into the field of view (FOV). The modulation transfer function (MTF) curves are above 0.4 at 20 line pairs per millimeter (lp/mm) which meets the infrared reconnaissance requirement. This work provides essential insight and guidance for aberration correction in off-axis freeform system design. PMID:27557003

  20. Aberrant Effective Connectivity in Schizophrenia Patients During Appetitive Conditioning

    Directory of Open Access Journals (Sweden)

    Andreea Oliviana Diaconescu

    2011-01-01

    Full Text Available It has recently been suggested that schizophrenia involves dysfunction in brain connectivity at a neural level, and a dysfunction in reward processing at a behavioural level. The purpose of the present study was to link these two levels of analyses by examining effective connectivity patterns between brain regions mediating reward learning in patients with schizophrenia and healthy, age-matched controls. To this aim, we used functional magnetic resonance imaging (fMRI and galvanic skin recordings (GSR while patients and controls performed an appetitive conditioning experiment with visual cues as the conditioned (CS stimuli, and monetary reward as the appetitive unconditioned stimulus (US. Based on explicit stimulus contingency ratings, conditioning occurred in both groups; however, based on implicit, physiological GSR measures, patients failed to show differences between CS+ and CS- conditions. Healthy controls exhibited increased blood-oxygen-level dependent (BOLD activity across striatal, hippocampal and prefrontal regions and increased effective connectivity from the ventral striatum (VS to the orbitofrontal cortex (OFC BA 11 in the CS+ compared to the CS- condition. Compared to controls, patients showed increased BOLD activity across a similar network of brain regions, and increased effective connectivity from the striatum to hippocampus and prefrontal regions in the CS- compared to the CS+ condition. The findings of increased BOLD activity and effective connectivity in response to the CS- in patients with schizophrenia offer insight into the aberrant assignment of motivational salience to non-reinforced stimuli during conditioning that is thought to accompany schizophrenia.

  1. Refractive and diffractive neutron optics with reduced chromatic aberration

    Energy Technology Data Exchange (ETDEWEB)

    Poulsen, S.O., E-mail: stefan.poulsen@northwestern.edu [NEXMAP, Department of Physics, Technical University of Denmark, Anker Engelunds Vej 1, 2800 Kgs. Lyngby (Denmark); Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208 (United States); Poulsen, H.F. [NEXMAP, Department of Physics, Technical University of Denmark, Anker Engelunds Vej 1, 2800 Kgs. Lyngby (Denmark); Bentley, P.M. [European Spallation Source ESS AB, Box 176, 221 00 Lund (Sweden)

    2014-12-11

    Thermal neutron beams are an indispensable tool in physics research. The spatial and the temporal resolution attainable in experiments are dependent on the flux and collimation of the neutron beam which remain relatively poor, even for modern neutron sources. These difficulties may be mitigated by the use of optics for focusing and imaging. Refractive and diffractive optical elements, e.g. compound refractive lenses and Fresnel zone plates, are attractive due to their low cost, and simple alignment. These optical elements, however, suffer from chromatic aberration, which limit their effectiveness to highly monochromatic beams. This paper presents two novel concepts for focusing and imaging non-monochromatic thermal neutron beams with well-known optical elements: (1) a fast mechanical transfocator based on a compound refractive lens, which actively varies the number of individual lenses in the beam path to focus and image a time-of-flight beam, and (2) a passive optical element consisting of a compound refractive lens, and a Fresnel zone plate, which may focus and image both continuous and pulsed neutron beams.

  2. Antimetastatic therapy targeting aberrant sialylation profiles in cancer cells

    Directory of Open Access Journals (Sweden)

    Da Yong Lu

    2011-09-01

    Full Text Available Neoplasm metastases involve a fixed cascade of pathological processes, and are responsible for more than 60% cancer deaths worldwide and can only be controlled or inhibited by drugs now. Antimetastatic drugs targeting aberrantly sialylated in tumors have involved about a quarter of a century and might be a future therapeutic option apart from currently utilized antimetastatic drugs, such as antivascular and matrix metalloproteinase (MMP inhibitors. Since neoplasm tissues often manifest high levels of sialic acids and sialyl antigens or glycoligands, and some types of sialic acid analogue, such as N-glycolylneuraminic acid (Nau5Gc occurred in most tumor tissues, is absent in common humans, more attentions are needed to work with new therapeutic approaches to target these changes. Previously preliminary data have shown some compounds that inhibit some pathways of sialic acids can inhibit the tumor metastasis in vitro and tumor metastasis in experimental animal models. This type of pharmacological work can be helped by glycome investigations in order to deep understanding their mechanisms. As the central dogma of glycobiology is still unknown, some fundamental questions related to carbohydrate itself are even more welcoming and decisive to our understanding to nature of cancer. These types of work also need mathematical analysis of data. In this review, we will document and discuss the latest experimental therapeutic data and their clinical significance between cancer pathological profiles and therapeutics benefits.

  3. Sphere-cone-polynomial special window with good aberration characteristic

    Institute of Scientific and Technical Information of China (English)

    Wang Chao; Zhang Xin; Qu He-Meng; Wang Ling-Jie; Wang Yu

    2013-01-01

    Optical windows with external surfaces shaped to satisfy operational environment needs are known as special windows.A novel special window,a sphere-cone-polynomial (SCP) window,is proposed.The formulas of this window shape are given.An SCP MgF2 window with a fineness ratio of 1.33 is designed as an example.The field-of-regard (FOR) angle is ±75°.From the window system simulation results obtained with the calculated fluid dynamics (CFD) and optical design software,we find that compared to the conventional window forms,the SCP shape can not only introduce relatively less drag in the airflow,but also have the minimal effect on imaging.So the SCP window optical system can achieve a high image quality across a super wide FOR without adding extra aberration correctors.The tolerance analysis results show that the optical performance can be maintained with a reasonable fabricating tolerance to manufacturing errors.

  4. Astrocyte Reactivity Following Blast Exposure Involves Aberrant Histone Acetylation

    Science.gov (United States)

    Bailey, Zachary S.; Grinter, Michael B.; VandeVord, Pamela J.

    2016-01-01

    Blast induced neurotrauma (BINT) is a prevalent injury within military and civilian populations. The injury is characterized by persistent inflammation at the cellular level which manifests as a multitude of cognitive and functional impairments. Epigenetic regulation of transcription offers an important control mechanism for gene expression and cellular function which may underlie chronic inflammation and result in neurodegeneration. We hypothesize that altered histone acetylation patterns may be involved in blast induced inflammation and the chronic activation of glial cells. This study aimed to elucidate changes to histone acetylation occurring following injury and the roles these changes may have within the pathology. Sprague Dawley rats were subjected to either a 10 or 17 psi blast overpressure within an Advanced Blast Simulator (ABS). Sham animals underwent the same procedures without blast exposure. Memory impairments were measured using the Novel Object Recognition (NOR) test at 2 and 7 days post-injury. Tissues were collected at 7 days for Western blot and immunohistochemistry (IHC) analysis. Sham animals showed intact memory at each time point. The novel object discrimination decreased significantly between two and 7 days for each injury group (p processes. We have shown aberrant histone acetylation patterns involved in blast induced astrogliosis and cognitive impairments. Further understanding of their role in the injury progression may lead to novel therapeutic targets. PMID:27551260

  5. Heterogeneity of aberrant immunoglobulin expression in cancer cells

    Institute of Scientific and Technical Information of China (English)

    Duosha Hu; Ya Cao; Zhi Duan; Ming Li; Yiqun Jiang; Haidan Liu; Hui Zheng; Lili Li; Ann M Bode; Zigang Dong

    2011-01-01

    Accumulating evidence has shown that immunoglobulin (Ig) is 'unexpectedly' expressed by epithelial cancer cells and that it can promote tumor growth.The main purpose of this study was to explore the components of the cancerous Ig and its possible function.The presence of cancerous Ig in the Golgi apparatus was confirmed by immunofluorescence,indirectly suggesting that the cancerous Ig was processed and packaged in cancer cells.Western blot analysis and ELISA results indicated that cancer cells produced membrane Ig and secreted Ig into the supernatant fraction.The cancerous Ig consists of an α heavy chain and a κ light chain.Finally,by analyzing the Ig components pulled down by protein A beads,the cancerous Ig was found to be structurally distinct from normal Ig.The cancerous Ig was truncated or aberrant.Although the underlying mechanism that causes the abnormalities has not been determined,our current discoveries strengthen our previous findings and promise fruitful future explorations.

  6. Aberrant driving behaviors: a study of drivers in Beijing.

    Science.gov (United States)

    Shi, Jing; Bai, Yun; Ying, Xiwen; Atchley, Paul

    2010-07-01

    The addition of massive numbers of new drivers with varied driving experience to roads in China suggests it is important to understand the nature of aberrant driving behaviors for this new set of drivers. A paper-based and an Internet survey were administered. Factor analysis produced a five-factor structure for each survey. The distinction between violations and errors indicated in previous studies was confirmed. The violations included emotional violations, risky violations and self-willed violations, and the errors included inexperience errors and distraction errors. In contrast to previous work, age was not found to be a good predictor of violations though driving experience was. Contrary to expectations, non-automotive (bicycle) roadway experience or level of driving training failed to predict poor driving behavior. On-road experience is the key to risk for China's drivers. Good agreement between the paper-based and Internet surveys indicate online surveys to be a feasible way to conduct research of driving behavior at low cost. PMID:20441810

  7. Propranolol induced chromosomal aberrations in Chinese hamster ovary cell line

    Directory of Open Access Journals (Sweden)

    Mozhgan Sedigh-Ardekani

    2013-03-01

    Full Text Available Propranolol (PL, a non-selective beta-blocker, is a cardiovascular drug widely used to treat hypertension. The present study was concerned with assessing the cytogenetic effects of this drug on Chinese hamster ovary (CHO cell line. MTT assay was then carried out to determine the cytotoxicity index (IC50 of the drug. The IC50 value of PL was 0.43±0.02 mM. To investigate the clastogenic effects of the drug, chromatid and chromosome breaks and polyploidy in metaphases were analyzed. CHO cells were exposed to different concentrations of the drug (0.1, 0.2, 0.3, 0.4 mM for 24 hours. Considering that PL has liver metabolism, experiments were carried out in the presence and absence of the metabolic activation system (S9 mix. Mitomycin-C and sodium arsenite were used as positive controls. It was observed that in cells treated with different PL concentrations as 0.1, 0.2 and 0.3 mM, the frequency of chromatid and chromosome breaks as well as polyploidy increased when compared with untreated CHO cells. The addition of S9 mix significantly decreased the chromatid breaks, chromosome breaks and polyploidy compared to the treatment of PL alone. It is concluded that, PL causes chromatid and chromosome aberrations in CHO cell line and the metabolic activation system (S9 mix, playing an important role in drug cytotoxicity reduction.

  8. Aberrant left brachiocephalic vein: CT imaging findings and embryologic correlation

    International Nuclear Information System (INIS)

    Computed tomography was utilized to evaluate aberrant left brachiocephalic vein (ALBCV), an infrequently discussed congenital vascular anomaly among Chinese people. Associated vascular variation and possible embryonic correlation are discussed. Since 1990, a total of 14 cases of ALBCV have been reported in patients receiving CT scan of chest, and was mainly an incidental diagnosis. One case was confirmed angiographically and two others were confirmed by magnetic resonance imaging. Emphasis was placed on the entry of the azygos vein into the superior vena cava (SVC), the length of the SVC, and the presence of other cardiovascular abnormalities. Of the 14 cases of ALBCV, the level of azygos vein entry was higher than the origin of the SVC in 7 cases: 4 were approximately the same level and 3 were lower. The average length of the SVC was approximately 5.6 cm shorter than that of the general population, which is approximately 7.0 cm. Three cases had associated vascular anomaly. Most cases of ALBCV had azygos vein drainage level higher than or equal to the origin of the SVC. Right-sided aorta is one of the causes giving rise to the ALBCV during embryonic development. The CT scan remains a definitive diagnostic modality for ALBCV. (orig.)

  9. LSST Telescope Alignment Plan Based on Nodal Aberration Theory

    Science.gov (United States)

    Sebag, J.; Gressler, W.; Schmid, T.; Rolland, J. P.; Thompson, K. P.

    2012-04-01

    The optical alignment of the Large Synoptic Survey Telescope (LSST) is potentially challenging, due to its fast three-mirror optical design and its large 3.5° field of view (FOV). It is highly advantageous to align the three-mirror optical system prior to the integration of the complex science camera on the telescope, which corrects the FOV via three refractive elements and includes the operational wavefront sensors. A telescope alignment method based on nodal aberration theory (NAT) is presented here to address this challenge. Without the science camera installed on the telescope, the on-axis imaging performance of the telescope is diffraction-limited, but the field of view is not corrected. The nodal properties of the three-mirror telescope design have been analyzed and an alignment approach has been developed using the intrinsically linear nodal behavior, which is linked via sensitivities to the misalignment parameters. Since mirror figure errors will exist in any real application, a methodology to introduce primary-mirror figure errors into the analysis has been developed and is also presented.

  10. Phenotypic aberrations during micropropagation of Soymida febrifuga (Roxb. Adr. Juss

    Directory of Open Access Journals (Sweden)

    Kishore Kumar CHIRUVELLA

    2014-03-01

    Full Text Available Like most of the medicinal plants Soymida febrifuga (Meliaceae possess significance for its valuable secondary metabolites. Multiplication of this endemic plant is limited by difficulty in rooting of stem cuttings, high seedling mortality rates and low seed viability period. Hence efficient protocols for in vitro mass propagation has been established from field grown and aseptic seedlings explants. Strikingly, we observed aberrant structures such as vitrified shoots, faciated shoots, albino shoots as well shoot necrosis during its micropropagation. These phenotypic maladies were observed during organogenesis and rooting. Compared to other abnormalities, shoot necrosis nonetheless was frequent and pronounced leading to plant death. Shoots when subjected to rooting also displayed necrosis which was controlled by transferring to MS medium containing various concentrations and combinations of calcium levels, activated charcoal, glucose, fructose and auxins. Microshoots initiated roots on half strength MS medium with IBA and IAA individually or in combination within two weeks. MS half strength solid medium supplemented with CAN (556 mg l–1, CAP (1.0 mg l–1, IAA (2.0 mg l–1 and IBA (2.0 mg l–1 in combination was found to be more efficient in showing high frequency (95% of root regeneration. Rooted plantlets were successfully hardened and 70-85% of regenerated plants were successfully acclimatized to natural environment. In vitro derived plantlets were morphologically similar to in vivo plants.

  11. Profiles of aberrant white matter microstructure in fragile X syndrome.

    Science.gov (United States)

    Hall, Scott S; Dougherty, Robert F; Reiss, Allan L

    2016-01-01

    Previous studies attempting to quantify white matter (WM) microstructure in individuals with fragile X syndrome (FXS) have produced inconsistent findings, most likely due to the various control groups employed, differing analysis methods, and failure to examine for potential motion artifact. In addition, analyses have heretofore lacked sufficient specificity to provide regional information. In this study, we used Automated Fiber-tract Quantification (AFQ) to identify specific regions of aberrant WM microstructure along WM tracts in patients with FXS that differed from controls who were matched on age, IQ and degree of autistic symptoms. Participants were 20 patients with FXS, aged 10 to 23 years, and 20 matched controls. Using Automated Fiber-tract Quantification (AFQ), we created Tract Profiles of fractional anisotropy and mean diffusivity along 18 major WM fascicles. We found that fractional anisotropy was significantly increased in the left and right inferior longitudinal fasciculus (ILF), right uncinate fasciculus, and left cingulum hippocampus in individuals with FXS compared to controls. Conversely, mean diffusivity was significantly decreased in the right ILF in patients with FXS compared to controls. Age was significantly negatively associated with MD values across both groups in 11 tracts. Taken together, these findings indicate that FXS results in abnormal WM microstructure in specific regions of the ILF and uncinate fasciculus, most likely caused by inefficient synaptic pruning as a result of decreased or absent Fragile X Mental Retardation Protein (FMRP). Longitudinal studies are needed to confirm these findings.

  12. AN ABERRANT MUSCLE IN THE NECK – A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Anil

    2013-05-01

    Full Text Available ABSTRACT: During routine dissection of a 65 year old male cad aver, an unusual muscle was found on the right side of the neck. The aberrant muscle had a common origin with sternothyroid. Its distal end was a fleshy belly attached to the posterior as pects of manubrium sternum and medial end of first costal cartilage. The muscle ascended in supe ro-lateral direction crossing anterior to the common carotid artery and ascended as a slender ten don along the anterior wall of carotid sheath. In the middle third of the neck, it was accompanied by descendens hypoglossi. The tendon merged with the anterior wall of the carotid sheath in the uppe r part of the neck and was not discernible as a separate entity. Along with the carotid sheath, it was inserted to the base of the skull. Developmentally, the muscle appears to be the separ ated fibres from stylohyoid and sternohyoid line (supra- and infra- hyoid muscles that has lost its intermittent attachment to hyoid bone. Based on its attachments, the muscle can assi st sternocleidomastoid in ipsilateral tilting of th e head. As the muscle was found to be crossing in fro nt of the common carotid artery, the contraction of this muscle could compress the artery resulting in clinical symptoms. The opposite side of the neck did not show similar muscle. We did not find s imilar case reported in the literature

  13. Aberrant repair and fibrosis development in skeletal muscle

    Directory of Open Access Journals (Sweden)

    Mann Christopher J

    2011-05-01

    Full Text Available Abstract The repair process of damaged tissue involves the coordinated activities of several cell types in response to local and systemic signals. Following acute tissue injury, infiltrating inflammatory cells and resident stem cells orchestrate their activities to restore tissue homeostasis. However, during chronic tissue damage, such as in muscular dystrophies, the inflammatory-cell infiltration and fibroblast activation persists, while the reparative capacity of stem cells (satellite cells is attenuated. Abnormal dystrophic muscle repair and its end stage, fibrosis, represent the final common pathway of virtually all chronic neurodegenerative muscular diseases. As our understanding of the pathogenesis of muscle fibrosis has progressed, it has become evident that the muscle provides a useful model for the regulation of tissue repair by the local microenvironment, showing interplay among muscle-specific stem cells, inflammatory cells, fibroblasts and extracellular matrix components of the mammalian wound-healing response. This article reviews the emerging findings of the mechanisms that underlie normal versus aberrant muscle-tissue repair.

  14. Aberrations and focusability in large solid-state-laser systems

    International Nuclear Information System (INIS)

    Solid state lasers for fusion experiments must reliably deliver maximum power to small (approximately .5 mm) targets from stand-off focal distances of 1 m or more. This requirement places stringent limits upon the optical quality of the several major components - amplifiers, Faraday isolators, spatial filters - in each amplifier train. Residual static aberrations in optical components are transferred to the beam as it traverses the optical amplifier chain. Although individual components are typically less than lambda/20 for components less than 10 cm clear aperture; and less than lambda/10 for components less than 20 cm clear aperture; the large number of such components in optical series results in a wavefront error that may exceed one wave for modern solid state lasers. For pulse operation, the focal spot is additionally broadened by intensity dependent nonlinearities. Specific examples of the performance of large aperture components will be presented within the context of the Argus and Shiva laser systems, which are presently operational at Lawrence Livermore National Laboratory. Design requirements upon the larger aperture Nova laser components, up to 74 cm in clear aperture, will also be discussed; these pose a significant challenge to the optical industry

  15. Perceived no reference image quality measurement for chromatic aberration

    Science.gov (United States)

    Lamb, Anupama B.; Khambete, Madhuri

    2016-03-01

    Today there is need for no reference (NR) objective perceived image quality measurement techniques as conducting subjective experiments and making reference image available is a very difficult task. Very few NR perceived image quality measurement algorithms are available for color distortions like chromatic aberration (CA), color quantization with dither, and color saturation. We proposed NR image quality assessment (NR-IQA) algorithms for images distorted with CA. CA is mostly observed in images taken with digital cameras, having higher sensor resolution with inexpensive lenses. We compared our metric performance with two state-of-the-art NR blur techniques, one full reference IQA technique and three general-purpose NR-IQA techniques, although they are not tailored for CA. We used a CA dataset in the TID-2013 color image database to evaluate performance. Proposed algorithms give comparable performance with state-of-the-art techniques in terms of performance parameters and outperform them in terms of monotonicity and computational complexity. We have also discovered that the proposed CA algorithm best predicts perceived image quality of images distorted with realistic CA.

  16. Aberrant water homeostasis detected by stable isotope analysis.

    Directory of Open Access Journals (Sweden)

    Shannon P O'Grady

    Full Text Available While isotopes are frequently used as tracers in investigations of disease physiology (i.e., 14C labeled glucose, few studies have examined the impact that disease, and disease-related alterations in metabolism, may have on stable isotope ratios at natural abundance levels. The isotopic composition of body water is heavily influenced by water metabolism and dietary patterns and may provide a platform for disease detection. By utilizing a model of streptozotocin (STZ-induced diabetes as an index case of aberrant water homeostasis, we demonstrate that untreated diabetes mellitus results in distinct combinations, or signatures, of the hydrogen (delta2H and oxygen (delta18O isotope ratios in body water. Additionally, we show that the delta2H and delta18O values of body water are correlated with increased water flux, suggesting altered blood osmolality, due to hyperglycemia, as the mechanism behind this correlation. Further, we present a mathematical model describing the impact of water flux on the isotopic composition of body water and compare model predicted values with actual values. These data highlight the importance of factors such as water flux and energy expenditure on predictive models of body water and additionally provide a framework for using naturally occurring stable isotope ratios to monitor diseases that impact water homeostasis.

  17. Stable chromosome aberrations in the reconstruction of radiation doses

    International Nuclear Information System (INIS)

    Chromosome-type aberrations, such as dicentric and translocation chromosomes, are biomarkers of exposure to ionizing radiation. So far, analysis of dicentric chromosomes in peripheral blood lymphocytes has been the only method routinely used in biological dose assessment. During division of T cell precursors, proliferative death of cells containing dicentric chromosomes reduces the number of such lymphocytes in peripheral blood. Dicentrics are thus suitable for dose calculations during a reasonably short period after exposure to radiation. Unlike dicentrics, translocations persist in cell division and enable dose estimation over long time periods following exposure. A recent development in molecular biology, the FISH (fluorescence in situ hybridization) chromosome-painting technique, has opened the possibility for accurate recognition of translocations and thus retrospective determination of dose. The purpose of the present study was to evaluate the applicability of translocation analysis by means of FISH chromosome painting for retrospective dosimetry. In the construction of acute dose-effect curves for 60Co g-ray-induced chromosomal aberrations using FISH chromosome painting, translocations showed a linear-quadratic relationship to dose, similar to that seen in dicentrics. Donor-dependent translocation frequencies at control level and at low doses were observed. The linear part of the calibration curve for two way translocations, i.e. both translocation chromosomes present, proved to be more reliable than the comparable low-dose response for total translocations, which include both two- and one-way translocations. The results indicate that the linear part of the curve requires precise determination, particularly since application of the technique will probably cover mainly chronically exposed subjects. An opportunity to gain direct information on translocation persistence over time was opened by obtaining repeated samples from subjects accidentally exposed to

  18. Study on the design and Zernike aberrations of a segmented mirror telescope

    Institute of Scientific and Technical Information of China (English)

    Jiang Zhen-Yu; Li Lin; Huang Yi-Fan

    2009-01-01

    The segmented mirror telescope is widely used. The aberrations of segmented mirror systems are different from single mirror systems. This paper uses the Fourier optics theory to analyse the Zernike aberrations of segmented mirror systems. It concludes that the Zernike aberrations of segmented mirror systems obey the linearity theorem. The design of a segmented space telescope and segmented schemes are discussed, and its optical model is constructed. The computer simulation experiment is performed with this optical model to verify the suppositions. The experimental results confirm the correctness of the model.

  19. Wavefront aberration statistics in normal eye populations: are they well described by the Kolmogorov model?

    Science.gov (United States)

    Pailos, Eliseo; Bará, Salvador

    2014-06-01

    This Letter studies the statistics of wavefront aberrations in a sample of eyes with normal vision. Methods relying on the statistics of the measured wavefront slopes are used, not including the aberration estimation stage. Power-law aberration models, an extension of the Kolmogorov one, are rejected by χ2-tests performed on fits to the slope structure function data. This is due to the large weight of defocus and astigmatism variations in normal eyes. Models of only second-order changes are not ruled out. The results are compared with previous works in the area.

  20. Modeling low order aberrations in laser guide star adaptive optics systems

    OpenAIRE

    Clare, Richard M.; Van Dam, Marcos A.; Bouchez, Antonin H.

    2007-01-01

    When using a laser guide star (LGS) adaptive optics (AO) system, quasi-static aberrations are observed between the measured wavefronts from the LGS wavefront sensor (WFS) and the natural guide star (NGS) WFS. These LGS aberrations, which can be as much as 1200 nm RMS on the Keck II LGS AO system, arise due to the finite height and structure of the sodium layer. The LGS aberrations vary significantly between nights due to the difference in sodium structure. In this paper, we successfully model...

  1. Heavy ion-induced chromosomal aberrations analyzed by fluorescence in situ hybridization

    Energy Technology Data Exchange (ETDEWEB)

    Durante, M.; Gialanella, G.; Grossi, G.; Pugliese, M. [Univ. ``Federico II``, Naples (Italy). Dept. of Physics]|[INFN, Naples (Italy); Cella, L.; Greco, O. [Univ. ``Federico II``, Naples (Italy). Dept. of Physics; Furusawa, Y. [NIRS, Chiba (Japan); George, K.; Yang, T.C. [NASA Lyndon B. Johnson Space Center, Houston, TX (United States)

    1997-09-01

    We have investigated the effectiveness of heavy ions in the induction of chromosomal aberrations in mammalian cells by the recent technique of fluorescence in situ hybridization (FISH) with whole-chromosome probes. FISH-painting was used both in metaphase and interphase (prematurely condensed) chromosomes. The purpose of our experiments was to address the following problems: (a) the ratio of different types of aberrations as a function of radiation quality (search for biomarkers); (b) the ratio between aberrations scored in interphase and metaphase as a function of radiation quality (role of apoptosis); (c) differences between cytogenetic effects produced by different ions at the same LET (role of track structure). (orig./MG)

  2. Study on Differential Algebraic Method of Aberrations up to Arbitrary Order for Combined Electromagnetic Focusing Systems

    Institute of Scientific and Technical Information of China (English)

    CHENG Min; TANG Tiantong; YAO Zhenhua; ZHU Jingping

    2001-01-01

    Differential algebraic method is apowerful technique in computer numerical analysisbased on nonstandard analysis and formal series the-ory. It can compute arbitrary high order derivativeswith excellent accuracy. The principle of differentialalgebraic method is applied to calculate high orderaberrations of combined electromagnetic focusing sys-tems. As an example, third-order geometric aberra-tion coefficients of an actual combined electromagneticfocusing system were calculated. The arbitrary highorder aberrations are conveniently calculated by dif-ferential algebraic method and the fifth-order aberra-tion diagrams are given.

  3. Research on spontaneously emerged chromosomal aberrations in the periphery blood lymphocytes in cattle ('Busa' breed).

    Science.gov (United States)

    Hasanbasić, Danica; Rukavina, Dunja; Hodzić, Aida; Brka, Muhamed; Vegara, Mensur; Hamamdzić, Muhidin

    2007-11-01

    Knowledge of spontaneous aberrations, namely, of their frequency in non-irradiated cells is of paramount importance not only in cytogenetic research, but also in contemporary animal production. The paper deals with research on spontaneously emerged chromosomal aberrations in the peripheral blood lymphocytes in the cattle of 'Busa' breed. To obtain metaphase chromosomes the conventional method of lymphocyte cultivation was used, albeit slightly modified and adapted to the examined animals and the laboratory conditions. The research findings indicate that a certain percent of spontaneously emerged chromosomal aberrations of chromatid type (gap and break) have been found in the peripheral blood lymphocytes in the cattle of 'Busa' breed.

  4. Induction of chromosomal aberrations by propoxur in mouse bone marrow cells.

    Science.gov (United States)

    Agrawal, R C

    1999-12-01

    Propoxur is a widely used dithiocarbamate insecticide. In this study, the clastogenic effect of propoxur has been evaluated using chromosomal aberration assay in mouse bone marrow cells. Single i.p. administration of propoxur, at 25 mg/kg b.wt., a maximum tolerated dose (MTD) and 12.5 mg/kg b.wt (50% of MTD) have significantly induced different types of aberrations after 24 h of treatment. The aberrations were dose and time dependent and reached a maximum after 24 h of exposure. The results suggest a genotoxic potential of propoxur.

  5. Population spherical aberration: associations with ametropia, age, corneal curvature, and image quality

    Directory of Open Access Journals (Sweden)

    Kingston AC

    2013-05-01

    Full Text Available Amanda C Kingston,1,2 Ian G Cox11Bausch + Lomb, Rochester, NY, USA; 2Department of Biomedical Engineering, University of Rochester, Rochester, NY, USAPurpose: The aim of this analysis was to determine the total ocular wavefront aberration values of a large phakic population of physiologically normal, ametropic eyes, gathered under the same clinical protocol using the same diagnostic wavefront sensor.Materials and methods: Studies were conducted at multiple sites in Asia, North America, Europe, and Australia. A Bausch + Lomb Zywave II Wavefront Aberrometer (Rochester, NY, USA was used to measure the lower and higher order aberrations of each eye. Data analysis was conducted using linear regression analysis to determine the relationship between total spherical aberration, ametropia, age, corneal curvature, and image quality.Results: Linear regression analysis showed no correlation (r = 0.0207, P = 0.4874 between degree of ametropia and the amount of spherical aberration. There was also no correlation when the population was stratified into myopic and hyperopic refractive groups (rm = 0.0529, Pm = 0.0804 and rh = 0.1572, Ph = 0.2754. There was a statistically significant and weak positive correlation (r = 0.1962, P < 0.001 between age and the amount of spherical aberration measured in the eye; spherical aberration became more positive with increasing age. Also, there was a statistically significant and moderately positive correlation (r = 0.3611, P < 0.001 with steepness of corneal curvature; spherical aberration became more positive with increasing power of the anterior corneal surface. Assessment of image quality using optical design software (Zemax™, Bellevue, WA, USA showed that there was an overall benefit in correcting the average spherical aberration of this population.Conclusion: Analysis of this dataset provides insights into the inherent spherical aberration of a typical phakic, pre-presbyopic, population and provides the ability to

  6. Correction of cell-induced optical aberrations in a fluorescence fluctuation microscope

    CERN Document Server

    Leroux, Charles-Edouard; Wang, Irène; Delon, Antoine

    2014-01-01

    We describe the effect of optical aberrations on fluorescence fluctuations microscopy (FFM), when focusing through a single living cell. FFM measurements are performed in an aqueous fluorescent solution and prove to be a highly sensitive tool to assess the optical aberrations introduced by the cell. We demonstrate an adaptive optics (AO) system to remove the aberration-related bias in the FFM measurements. Our data show that AO is not only useful when imaging deep in tissues but also when performing FFM measurements through a single cellular layer. This work paves the way for the application of FFM to complex three-dimensional multicellular samples.

  7. Induction of Chromosomal Aberrations by Propoxur in Mouse Bone Marrow Ceils

    Institute of Scientific and Technical Information of China (English)

    R. C. AGRAWAL

    1999-01-01

    Propoxur is a widely used dithiocarbamate insecticide. In this study, the clastogenic effect of propoxur has been evaluated using chromosomal aberration assay in mouse bone marrow cells. Singlei. p. administration of propoxur, at 25 nag/kg b.wt., a maximum tolerated dose (MTD) and 12.5mg/kg b.wt (50% of MTD) have significantly induced different types of aberrations after 24 h of treatment. The aberrations were dose and time dependent and reached a maximum after 24 h of exposure. The sresult suggest a genotoxic potential of propoxur.

  8. Lipid rafts participate in aberrant degradative autophagic-lysosomal pathway of amyloid-beta peptide in Alzheimer’s disease

    Institute of Scientific and Technical Information of China (English)

    Xin Zhou; Chun Yang; Yufeng Liu; Peng Li; Huiying Yang; Jingxing Dai; Rongmei Qu; Lin Yuan

    2014-01-01

    Amyloid-beta peptide is the main component of amyloid plaques, which are found in Alzhei-mer’s disease. The generation and deposition of amyloid-beta is one of the crucial factors for the onset and progression of Alzheimer’s disease. Lipid rafts are glycolipid-rich liquid domains of the plasma membrane, where certain types of protein tend to aggregate and intercalate. Lipid rafts are involved in the generation of amyloid-beta oligomers and the formation of amyloid-beta peptides. In this paper, we review the mechanism by which lipid rafts disturb the aberrant deg-radative autophagic-lysosomal pathway of amyloid-beta, which plays an important role in the pathological process of Alzheimer’s disease. Moreover, we describe this mechanism from the view of the Two-system Theory of fasciology and thus, suggest that lipid rafts may be a new target of Alzheimer’s disease treatment.

  9. Location of quarries of non traditional stony materials in the architecture of Madrid: the Crypt of the Cathedral of Santa María la Real de la Almudena

    Directory of Open Access Journals (Sweden)

    Gómez-Heras, M.

    2004-06-01

    Full Text Available The combination between petrological data and historical documentation sources is necessary to establish an accurate methodology for the location of the original quarries of the stony materials used in a determinate historical building. The petrographical and petrophisical data correlation combined with a multivariate statistical analysis, by means of similarity indexes of both the materials in the building and the probable source geological formations, allows the location even when the documental sources would he incomplete or lost, or when the source areas would be modified. The works of location of original quarries used in architectural heritage are important since they allow improving the works of restoration on a building by means of the possibility of using identical materials for substitution or reintegration of decayed elements. The establishment of the original areas also offers the possibility of obtaining unaltered semipiés to evaluate the state and processes of decay of the building as well as to use this rough material to test the effectivity and durability of protective arid consolidant treatments in the building and monuments. The aim of this work has been to characterize and to locate the origin of the stony material in the stonework of the Crypt of the Cathedral of Santa María la Real de la Almudena (Madrid. These stone types came from quarries located in Viana de Jadraque (Guadalajara, Spain and in the central area of Portugal. These materials do not correspond with the traditional ones used in the city of Madrid and its presence is due to the opening of new ways of transport in the second half of the 19"' centuiy.

    Para establecer una metodología adecuada con el fin de localizar las canteras originales de los materiales pétreos de construcción utilizados en un determinado edificio histórico se necesita combinar datos petrológicos y fuentes de documentación histórica. La correlación de los datos petrogr

  10. Phase and group velocity of focused, pulsed Gaussian beams in the presence and absence of primary aberrations

    International Nuclear Information System (INIS)

    This work presents a study on the phase- and group-velocity variations of focused, pulsed Gaussian beams during the propagation through the focal region along the optical axis. In the aberration-free case, it is discussed how the wavelength dependence of beam properties alters the group velocity, and how a chromatic aberration-like effect can arise even when focusing is performed with an element that does not have chromatic aberration. It is also examined what effects primary spherical aberration, astigmatism, coma, curvature of field and distortion, along with chromatic aberration, have on the phase- and group-velocity changes occurring during propagation through focus. (paper)

  11. Routine laboratory diagnosis of chromosome aberrations in multiple myeloma

    Directory of Open Access Journals (Sweden)

    Yuet-Meng Chin

    2014-08-01

    Full Text Available Multiple Myeloma (MM is a Plasma Cell (PC malignancy characterized by proliferation of differentiated B cells mainly in the bone marrow. Genetic abnormalities are powerful prognostic factors in MM for risk stratification and therapeutic strategies. The standard diagnostic tests to detect genetic abnormalities in MM include Conventional Cytogenetic Analysis (CCA and Interphase Fluorescence In Situ Hybridization (FISH. Due to the low proliferative activity of the abnormal clone, only 30-50% of newly diagnosed MM demonstrate an abnormal karyotype by CCA. CCA is a biological test which requires dividing cells for analysis. The t(4;14 translocation which carries a poor prognosis is cryptic and cannot be detected by CCA. These limitations were overcome partly by the incorporation of interphase FISH as a routine diagnostic test in MM. There is an international consensus that FISH should be performed in all newly diagnosed MM to detect high-risk genetic abnormalities. FISH testing must be done on purified PCs or by simultaneous labeling of cytoplasmic immunoglobulin light chain to allow identification of PCs. The minimum essential abnormalities to test for are t(4;14, t(14;16 and del(17(p13. However, there is no consensus on the optimal protocol for CCA and interphase FISH. We review here the types of chromosomal aberrations found in MM, the prognostic significance of these abnormalities, methodologies in CCA to improve on the low yield of abnormal karyotypes, and protocols in interphase FISH. [Int J Res Med Sci 2014; 2(4.000: 1241-1247

  12. Aberrant Behaviors and Road Accidents among Iranian Truck Drivers, 2010

    Directory of Open Access Journals (Sweden)

    Amir Houshang Mehrparvar

    2011-12-01

    Full Text Available structural dimensions of which as well as technologic failures such as road quality, and tech-nical faults of automobiles, need to be assessed in detail. Iran has the first order in the world for deadly road accidents. This study was designed to assess the association between aberrant behaviors of truck drivers and the incidence of road accidents in Yazd, center of Iran, in 2010.Methods: This cross-sectional descriptive-analytic study was conducted on 300 truck drivers in Yazd. We used 3 questionnaires, including one for demographic data, Driver Behavior Questionnaire (DBQ, and one for drivers' self-evaluation of the of their driving.Results: Five types of the behavior had the highest frequency: Misjudge speed of oncoming vehicle when overtaking.; Deliberately disregard the speed limits late at night or very early in the morning.; Ignore 'give way' signs, and narrowly avoid colliding with traffic having right of way.; Stuck behind a slow-moving vehicle on a two-lane highway, you are driven by frustration to try to overtake in risky circumstances.; Drive with only 'half-an-eye' on the road while looking at a map, changing a cassette or radio channel, etc. The more the driver's driv-ing was influenced by emotional and mental states the more deliberate violations and slips.Conclusion: Among truck drivers, safety has not developed sufficiently, and because of the dangers of road accidents both for the drivers and other people and its economic losses, the importance of the presenting some solutions is completely obvious.

  13. Angelman syndrome: A review highlighting musculoskeletal and anatomical aberrations.

    Science.gov (United States)

    Sachdeva, Rohit; Donkers, Sarah J; Kim, Soo Y

    2016-07-01

    Angelman's syndrome (AS) is a genetic neurodevelopment disorder. The cause is a known abnormality involving the maternal inherited ubiquitin-protein ligase (UBE3A) gene. Clinical characteristics universal to the disorder are well documented in the literature and include developmental delay, seizures, ataxia, altered tone, severely impaired speech and intellect, as well as an overall happy demeanor, frequent bouts of laughter, and hypermotoric behavior. Associated with this disorder are several musculoskeletal aberrations. To date, a review of case studies reporting on these musculoskeletal changes has not been carried out. Thus, the purpose of this paper was to provide an overview of the musculoskeletal changes present in individuals with AS. In our review of 21 case reports from 1965-2013, the most consistently reported anatomical changes were of the craniofacial region. These include microcephaly, brachycephaly, a palpable occipital groove, prognathism, and wide spaced teeth. Other musculoskeletal abnormalities less frequently reported in the literature include scoliosis, excessive lumbar lordosis, and pes planus. Given that the majority of the case reports reviewed was of young children, the possibility of underreporting musculoskeletal changes which may manifest in the later years of life may be present. Early diagnosis and interventions to minimize secondary complications are crucial to maintain quality of life. An overall multidisciplinary approach is emphasized to maximize developmental potential for these individuals. Future prospective studies that follow patients into adulthood are needed to better understand the prevalence and development of secondary musculoskeletal changes, which in turn can inform intervention techniques and preventative measures. Clin. Anat. 29:561-567, 2016. © 2015 Wiley Periodicals, Inc.

  14. Angelman syndrome: A review highlighting musculoskeletal and anatomical aberrations.

    Science.gov (United States)

    Sachdeva, Rohit; Donkers, Sarah J; Kim, Soo Y

    2016-07-01

    Angelman's syndrome (AS) is a genetic neurodevelopment disorder. The cause is a known abnormality involving the maternal inherited ubiquitin-protein ligase (UBE3A) gene. Clinical characteristics universal to the disorder are well documented in the literature and include developmental delay, seizures, ataxia, altered tone, severely impaired speech and intellect, as well as an overall happy demeanor, frequent bouts of laughter, and hypermotoric behavior. Associated with this disorder are several musculoskeletal aberrations. To date, a review of case studies reporting on these musculoskeletal changes has not been carried out. Thus, the purpose of this paper was to provide an overview of the musculoskeletal changes present in individuals with AS. In our review of 21 case reports from 1965-2013, the most consistently reported anatomical changes were of the craniofacial region. These include microcephaly, brachycephaly, a palpable occipital groove, prognathism, and wide spaced teeth. Other musculoskeletal abnormalities less frequently reported in the literature include scoliosis, excessive lumbar lordosis, and pes planus. Given that the majority of the case reports reviewed was of young children, the possibility of underreporting musculoskeletal changes which may manifest in the later years of life may be present. Early diagnosis and interventions to minimize secondary complications are crucial to maintain quality of life. An overall multidisciplinary approach is emphasized to maximize developmental potential for these individuals. Future prospective studies that follow patients into adulthood are needed to better understand the prevalence and development of secondary musculoskeletal changes, which in turn can inform intervention techniques and preventative measures. Clin. Anat. 29:561-567, 2016. © 2015 Wiley Periodicals, Inc. PMID:26480021

  15. High-order aberration control during exposure for leading-edge lithography projection optics

    Science.gov (United States)

    Ohmura, Yasuhiro; Tsuge, Yosuke; Hirayama, Toru; Ikezawa, Hironori; Inoue, Daisuke; Kitamura, Yasuhiro; Koizumi, Yukio; Hasegawa, Keisuke; Ishiyama, Satoshi; Nakashima, Toshiharu; Kikuchi, Takahisa; Onda, Minoru; Takase, Yohei; Nagahiro, Akimasa; Isago, Susumu; Kawahara, Hidetaka

    2016-03-01

    High throughput with high resolution imaging has been key to the development of leading-edge microlithography. However, management of thermal aberrations due to lens heating during exposure has become critical for simultaneous achievement of high throughput and high resolution. Thermal aberrations cause CD drift and overlay error, and these errors lead directly to edge placement errors (EPE). Management and control of high order thermal aberrations is a critical requirement. In this paper, we will show practical performance of the lens heating with dipole and other typical illumination conditions for finer patterning. We confirm that our new control system can reduce the high-order aberrations and enable critical-dimension uniformity CDU during the exposure.

  16. Induction of chromosome aberrations in two lines of cultured cells using different types of radiation

    International Nuclear Information System (INIS)

    The induction of chromosome aberrations has been investigated in two lines of cultured cells for different types of radiation. The obtained results are compared with information on induction of cell reproductive death and malignant transformation. (Auth.)

  17. Gametocidal chromosomes enhancing chromosome aberration in common wheat induced by 5-azacytidine.

    Science.gov (United States)

    Su, W-Y; Cong, W-W; Shu, Y-J; Wang, D; Xu, G-H; Guo, C-H

    2013-01-01

    The gametocidal (Gc) chromosome from Aegilops spp induces chromosome mutation, which is introduced into common wheat as a tool of chromosome manipulation for genetic improvement. The Gc chromosome functions similar to a restriction-modification system in bacteria, in which DNA methylation is an important regulator. We treated root tips of wheat carrying Gc chromosomes with the hypomethylation agent 5-azacytidine; chromosome breakage and micronuclei were observed in these root tips. The frequency of aberrations differed in wheat containing different Gc chromosomes, suggesting different functions inducing chromosome breakage. Gc chromosome 3C caused the greatest degree of chromosome aberration, while Gc chromosome 3C(SAT) and 2C caused only slight chromosome aberration. Gc chromosome 3C induced different degrees of chromosome aberration in wheat varieties Triticum aestivum var. Chinese Spring and Norin 26, demonstrating an inhibition function in common wheat. PMID:23884766

  18. Right aortic arch with aberrant left innominate artery arising from Kommerell's diverticulum*

    Science.gov (United States)

    Faistauer, Ângela; Torres, Felipe Soares; Faccin, Carlo Sasso

    2016-01-01

    We report a case of an uncommon thoracic aorta anomaly-right aortic arch with aberrant left innominate artery arising from Kommerell's diverticulum-that went undiagnosed until adulthood. PMID:27777481

  19. Correction of chromatic aberrations at television registration of image through protective viewing systems

    Science.gov (United States)

    Kulyas, Oleg L.; Nikitin, Konstantin A.

    2016-03-01

    Ways of chromatic aberration in images are examined and analyzed which are generated at television supervision through protective glasses of a considerable thickness. The results of experimental check up of the given method of correction is introduced and described.

  20. Modeling the Effect of Wave-front Aberrations in Fiber-based Scanning Optical Microscopy

    NARCIS (Netherlands)

    Verstraete, H.R.G.W.; Verhaegen, M.H.G.; Kalkman, J.

    2013-01-01

    In scanning microscopy and optical coherence tomography, aberrations of the wave-front cause a loss in intensity and resolution. Intensity and resolution are quantified using Fresnel propagation, Fraunhofer diffraction, and the calculation of overlap integrals.

  1. Design of macro-filter-lens with simultaneous chromatic and geometric aberration correction.

    Science.gov (United States)

    Prasad, Dilip K; Brown, Michael S

    2014-01-01

    A macro-filter-lens design that can correct for chromatic and geometric aberrations simultaneously while providing for a long focal length is presented. The filter is easy to fabricate since it involves two spherical surfaces and a planar surface. Chromatic aberration correction is achieved by making all the rays travel the same optical distance inside the filter element (negative meniscus). Geometric aberration is corrected for by the lens element (plano-convex), which makes the output rays parallel to the optic axis. This macro-filter-lens design does not need additional macro lenses and it provides an inexpensive and optically good (aberration compensated) solution for macro imaging of objects not placed close to the camera.

  2. Adrenal hyperplasia, tumours in mice in connection with aberrant pituitary-gonadal function

    OpenAIRE

    Bernichtein, Sophie; Peltoketo, Hellevi; Huhtaniemi, Ilpo

    2009-01-01

    Adrenal hyperplasia, tumours in mice in connection with aberrant pituitary-gonadal function UNITED KINGDOM (Bernichtein, Sophie) UNITED KINGDOM Received: 2008-08-25 Revised: 2008-10-08 Accepted: 2008-10-08

  3. Visual performance and aberration associated with contact lens wear in patients with keratoconus: a pilot study

    Directory of Open Access Journals (Sweden)

    Abdu M

    2014-08-01

    Full Text Available Mustafa Abdu, Norhani Mohidin, Bariah Mohd-Ali Optometry and Vision Science Program, School of Healthcare Sciences, Faculty of Health Science, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia Background: Rigid gas permeable (RGP and silicone hydrogel (SH contact lenses with specific designs are currently being used to improve visual function in patients with keratoconus. However, there are minimal data available comparing the effects of these lenses on visual function in patients with keratoconus. The objectives of this study were to compare visual acuity and contrast sensitivity using spectacles, RGP lenses, and SH lenses, and to evaluate the effects of RGP and SH lenses on higher-order aberrations and visual quality in eyes with keratoconus. The relationship between visual outcomes, aberration, and visual quality were also examined. Methods: This was a pilot study involving 13 eyes from nine subjects with keratoconus. Subjects were fitted with RGP and SH contact lenses. Visual acuity and contrast sensitivity were measured using Snellen and Pelli-Robson charts, respectively. Ocular aberrations and visual quality were measured using an OPD-Scan II device. All measurements were conducted before and after contact lens wear. Results: Significantly better visual acuity was obtained with RGP lenses than with spectacles or SH lenses (P<0.001. No significant difference in contrast sensitivity values was detected between RGP and SH lenses (P=0.06. Both SH and RGP lenses significantly reduced total ocular and higher-order aberrations (P<0.001 when compared with spectacles, but RGP lenses reduced trefoil, coma, and spherical aberrations more than SH lenses. No significant difference in astigmatic aberrations was found between RGP and SH lenses (P=0.12. Negative correlations were found between visual acuity and coma aberration and contrast sensitivity with higher-order aberrations and coma, trefoil, and astigmatic

  4. Computer aided analysis of additional chromosome aberrations in Philadelphia chromosome positive acute lymphoblastic leukaemia using a simplified computer readable cytogenetic notation

    Directory of Open Access Journals (Sweden)

    Mohr Brigitte

    2003-01-01

    Full Text Available Abstract Background The analysis of complex cytogenetic databases of distinct leukaemia entities may help to detect rare recurring chromosome aberrations, minimal common regions of gains and losses, and also hot spots of genomic rearrangements. The patterns of the karyotype alterations may provide insights into the genetic pathways of disease progression. Results We developed a simplified computer readable cytogenetic notation (SCCN by which chromosome findings are normalised at a resolution of 400 bands. Lost or gained chromosomes or chromosome segments are specified in detail, and ranges of chromosome breakpoint assignments are recorded. Software modules were written to summarise the recorded chromosome changes with regard to the respective chromosome involvement. To assess the degree of karyotype alterations the ploidy levels and numbers of numerical and structural changes were recorded separately, and summarised in a complex karyotype aberration score (CKAS. The SCCN and CKAS were used to analyse the extend and the spectrum of additional chromosome aberrations in 94 patients with Philadelphia chromosome positive (Ph-positive acute lymphoblastic leukemia (ALL and secondary chromosome anomalies. Dosage changes of chromosomal material represented 92.1% of all additional events. Recurring regions of chromosome losses were identified. Structural rearrangements affecting (pericentromeric chromosome regions were recorded in 24.6% of the cases. Conclusions SCCN and CKAS provide unifying elements between karyotypes and computer processable data formats. They proved to be useful in the investigation of additional chromosome aberrations in Ph-positive ALL, and may represent a step towards full automation of the analysis of large and complex karyotype databases.

  5. EFFECT OF SPHERICAL ABERRATION INTRODUCED BY WATER SOLUTION ON TRAPPING FORCE

    Institute of Scientific and Technical Information of China (English)

    YAO XIN-CHENG; LI ZHAO-LIN; GUO HONG-LIAN; CHENG BING-YING; ZHANG DAO-ZHONG; HAN XUE-HAI

    2000-01-01

    Trapping force of an optical tweezers system with an oil immersion objective is calculated with a ray-optics model.Results indicate that the trapping force will be decreased as a result of the introduction of spherical aberration,which is caused by the refractive mismatch between objective oil and water,when the sample manipulated is suspended in a water solution.The effect of spherical aberration will be serious when the detection depth of the optical tweezers is enhanced.

  6. Clinicopathologic Study of Chromosomal Aberrations in Ocular Adnexal Lymphomas of Korean Patients

    OpenAIRE

    Choung, Hokyung; Kim, Young A; Kim, Namju; Lee, Min Joung; Khwarg, Sang In

    2015-01-01

    Purpose The incidence and clinical correlation of MALT1 translocation and chromosomal numerical aberrations in Korean patients with ocular adnexal mucosa associated lymphoid tissue (MALT) lymphoma have not yet been reported. We investigated the incidence and clinicopathologic relationship of these chromosomal aberrations in ocular adnexal MALT lymphomas in a Korean population. Methods Thirty ocular adnexal MALT lymphomas were investigated for the t(11;18) API2-MALT1, t(14;18) IgH-MALT1 transl...

  7. Chromosomal aberrations detected by comparative genomic hybridization technique (CGH in invasive ductal carcinoma of breast

    Directory of Open Access Journals (Sweden)

    Nooshiravanpour P

    2007-10-01

    Full Text Available Background: Nonlethal genetic damage is the basis for carcinogenesis. As various gene aberrations accumulate, malignant tumors are formed, regardless of whether the genetic damage is subtle or large enough to be distinguished in a karyotype. The study of chromosomal changes in tumor cells is important in the identification of oncogenes and tumor suppressor genes by molecular cloning of genes in the vicinity of chromosomal aberrations. Furthermore, some specific aberrations can be of great diagnostic and prognostic value. Comparative genomic hybridization (CGH is used to screen the entire genome for the detection and/or location chromosomal copy number changes.Methods: In this study, frozen sections of 20 primary breast tumors diagnosed as invasive ductal carcinoma from the Cancer Institute of Imam Khomeini Hospital, Tehran, Iran, were studied by CGH to detect chromosomal aberrations. We compared histopathological and immunohistochemical findings.Results: Hybridization in four of the cases was not optimal for CGH analysis and they were excluded from the study. DNA copy number changes were detected in 12 (75% of the remaining 16 cases. Twenty-one instances of chromosomal aberrations were detected in total, including: +1q, +17q, +8q, +20q, -13q, -11q, -22q, -1p, -16q, -8p. The most frequent were +1q, +17q, +8q, -13q, similar to other studies. In three cases, we detected -13q, which is associated with axillary lymph node metastasis and was reported in one previous study. The mean numbers of chromosomal aberrations per tumor in metastatic and nonmetastatic tumors was 1.5 and 1, respectively. No other association between detected chromosomal aberrations and histopathological and immunohistochemical findings were seen.Conclusion: Since intermediately to widely invasive carcinomas are more likely to have chromosomal aberrations, CGH can be a valuable prognostic tool. Furthermore, CGH can be used to detect targeting molecules within novel amplifications

  8. Prostate Cancer, Prostate Cancer Death, and Death from Other Causes, Among Men with Metabolic Aberrations

    OpenAIRE

    Häggström, Christel; Stocks, Tanja; Nagel, Gabriele; Manjer, Jonas; Bjørge, Tone; Hallmans, Göran; Engeland, Anders; Ulmer, Hanno; Lindkvist, Bjorn; Selmer, Randi; Concin, Hans; Tretli, Steinar; Jonsson, Håkan; Stattin, Pär

    2014-01-01

    Background: Few previous studies of metabolic aberrations and prostate cancer risk have taken into account the fact that men with metabolic aberrations have an increased risk of death from causes other than prostate cancer. The aim of this study was to calculate, in a real-life scenario, the risk of prostate cancer diagnosis, prostate cancer death, and death from other causes. Methods: In the Metabolic Syndrome and Cancer Project, prospective data on body mass index, blood pressure, glucose, ...

  9. Increased risk of cancer in radon-exposed miners with elevated frequency of chromosomal aberrations.

    Science.gov (United States)

    Smerhovsky, Zdenek; Landa, Karel; Rössner, Pavel; Juzova, Dagmar; Brabec, Marek; Zudova, Zdena; Hola, Nora; Zarska, Hana; Nevsimalova, Emilie

    2002-02-15

    In spite of the extensive use of cytogenetic analysis of human peripheral blood lymphocytes in the biomonitoring of exposure to various mutagens and carcinogens, the long-term effects of an increased frequency of chromosomal aberrations in individuals are still uncertain. Few epidemiologic studies have addressed this issue, and a moderate risk of cancer in individuals with an elevated frequency of chromosomal aberrations has been observed. In the present study, we analyzed data on 1323 cytogenetic assays and 225 subjects examined because of occupational exposures to radon (range of exposure from 1.7 to 662.3 working level month (WLM)). Seventy-five subjects were non-smokers. We found 36 cases of cancer in this cohort. Chromatid breaks were the most frequently observed type of aberrations (mean frequency 1.2 per 100 cells), which statistically significantly correlated with radon exposure (Spearman's correlation coefficient R=0.22, P<0.001). Also, the frequency of aberrant cells (median of 2.5%) correlated with radon exposure (Spearman's correlation coefficient R=0.16, P<0.02). Smoking and silicosis were not associated with results of cytogenetic analyses. The Cox regression models, which accounted for the age at time of first cytogenetic assay, radon exposure, and smoking showed strong and statistically significant associations between cancer incidence and frequency of chromatid breaks and frequency of aberrant cells, respectively. A 1% increase in the frequency of aberrant cells was paralleled by a 62% increase in risk of cancer (P<0.000). An increase in frequency of chromatid breaks by 1 per 100 cells was followed by a 99% increase in risk of cancer (P<0.000). We obtained similar results when we analyzed the incidence of lung cancer and the incidence other than lung cancer separately. Contrary to frequency of chromatid breaks and frequency of aberrant cells, the frequency of chromatid exchanges, and chromosome-type aberrations were not predictive of cancer.

  10. Combining noncontingent reinforcement and differential reinforcement schedules as treatment for aberrant behavior.

    OpenAIRE

    Marcus, B A; Vollmer, T R

    1996-01-01

    Research has shown that noncontingent reinforcement (NCR) can be an effective behavior-reduction procedure when based on a functional analysis. The effects of NCR may be a result of elimination of the contingency between aberrant behavior and reinforcing consequences (extinction) or frequent and free access to reinforcers that may reduce the participant's motivation to engage in aberrant behaviors or mands. If motivation is momentarily reduced, behavior such as mands may not be sensitive to p...

  11. Endovascular Treatment of an Aneurysmal Aberrant Systemic Artery Supplying a Pulmonary Sequestrum

    DEFF Research Database (Denmark)

    Kristensen, Katrine Lawaetz; Duus, Louise Aarup; Elle, Bo

    2015-01-01

    An aberrant systemic artery originating from the abdominal aorta supplying a pulmonary sequestration is a rare congenital malformation. This causes a left-to-left shunt. Symptoms include recurrent pneumonias, hemoptysis, and, in the long term, heart failure. Aneurysm of the aberrant vessel...... aneurysmal branch from the abdominal aorta to the normal basal segments of the lung, successfully occluded with an Amplatzer Vascular Plug II (AVP II, St.Jude Medical, MN, USA) alone....

  12. Aberration corrected and monochromated environmental transmission electron microscopy: challenges and prospects for materials science

    DEFF Research Database (Denmark)

    Hansen, Thomas Willum; Wagner, Jakob Birkedal; Dunin-Borkowski, Rafal E.

    2010-01-01

    The latest generation of environmental transmission electron microscopes incorporates aberration correctors and monochromators, allowing studies of chemical reactions and growth processes with improved spatial resolution and spectral sensitivity. Here, we describe the performance of such an instr......The latest generation of environmental transmission electron microscopes incorporates aberration correctors and monochromators, allowing studies of chemical reactions and growth processes with improved spatial resolution and spectral sensitivity. Here, we describe the performance...

  13. Phase Aberration and Attenuation Effects on Acoustic Radiation Force-Based Shear Wave Generation.

    Science.gov (United States)

    Carrascal, Carolina Amador; Aristizabal, Sara; Greenleaf, James F; Urban, Matthew W

    2016-02-01

    Elasticity is measured by shear wave elasticity imaging (SWEI) methods using acoustic radiation force to create the shear waves. Phase aberration and tissue attenuation can hamper the generation of shear waves for in vivo applications. In this study, the effects of phase aberration and attenuation in ultrasound focusing for creating shear waves were explored. This includes the effects of phase shifts and amplitude attenuation on shear wave characteristics such as shear wave amplitude, shear wave speed, shear wave center frequency, and bandwidth. Two samples of swine belly tissue were used to create phase aberration and attenuation experimentally. To explore the phase aberration and attenuation effects individually, tissue experiments were complemented with ultrasound beam simulations using fast object-oriented C++ ultrasound simulator (FOCUS) and shear wave simulations using finite-element-model (FEM) analysis. The ultrasound frequency used to generate shear waves was varied from 3.0 to 4.5 MHz. Results: The measured acoustic pressure and resulting shear wave amplitude decreased approximately 40%-90% with the introduction of the tissue samples. Acoustic intensity and shear wave displacement were correlated for both tissue samples, and the resulting Pearson's correlation coefficients were 0.99 and 0.97. Analysis of shear wave generation with tissue samples (phase aberration and attenuation case), measured phase screen, (only phase aberration case), and FOCUS/FEM model (only attenuation case) showed that tissue attenuation affected the shear wave generation more than tissue aberration. Decreasing the ultrasound frequency helped maintain a focused beam for creation of shear waves in the presence of both phase aberration and attenuation.

  14. Schizotypal Perceptual Aberrations of Time: Correlation between Score, Behavior and Brain Activity

    OpenAIRE

    Shahar Arzy; Christine Mohr; Istvan Molnar-Szakacs; Olaf Blanke

    2011-01-01

    A fundamental trait of the human self is its continuum experience of space and time. Perceptual aberrations of this spatial and temporal continuity is a major characteristic of schizophrenia spectrum disturbances – including schizophrenia, schizotypal personality disorder and schizotypy. We have previously found the classical Perceptual Aberration Scale (PAS) scores, related to body and space, to be positively correlated with both behavior and temporo-parietal activation in healthy participan...

  15. Adaptive optics full-field OCT: a resolution almost insensitive to aberrations (Conference Presentation)

    Science.gov (United States)

    Xiao, Peng; Fink, Mathias; Boccara, A. Claude

    2016-03-01

    A Full-Field OCT (FFOCT) setup coupled to a compact transmissive liquid crystal spatial light modulator (LCSLM) is used to induce or correct aberrations and simulate eye examinations. To reduce the system complexity, strict pupil conjugation was abandoned. During our work on quantifying the effect of geometrical aberrations on FFOCT images, we found that the image resolution is almost insensitive to aberrations. Indeed if the object channel PSF is distorted, its interference with the reference channel conserves the main feature of an unperturbed PSF with only a reduction of the signal level. This unique behavior is specific to the use of a spatially incoherent illumination. Based on this, the FFOCT image intensity was used as the metric for our wavefront sensorless correction. Aberration correction was first conducted on an USAF resolution target with the LSCLM as both aberration generator and corrector. A random aberration mask was induced, and the low-order Zernike Modes were corrected sequentially according to the intensity metric function optimization. A Ficus leaf and a fixed mouse brain tissue slice were also imaged to demonstrate the correction of sample self-induced wavefront distortions. After optimization, more structured information appears for the leaf imaging. And the high-signal fiber-like myelin fiber structures were resolved much more clearly after the whole correction process for mouse brain imaging. Our experiment shows the potential of this compact AO-FFOCT system for aberration correction imaging. This preliminary approach that simulates eyes aberrations correction also opens the path to a simple implementation of FFOCT adaptive optics for retinal examinations.

  16. EFFECT OF SHORT-TERM SOFT CONTACT LENS WEAR ON HUMAN OCULAR ABERRATIONS

    Institute of Scientific and Technical Information of China (English)

    YU Jing; CHEN Yi-hui; CHEN Hui; SHENG Min-jie

    2009-01-01

    Objective To evaluate the effect of short-term soft contact lens (SCLs) wearing on human ocular aberrations (HOA).Methods This prospective study included 50 eyes of 50 young volunteers wearing SCLs for 1month. The ocular aberrations were measured by Allegretto Wavefront Analyzer. The root-mean-square (RMS) values of the general (RMSG), higher-order (RMSH), first to sixth order (RMS1 to RMS6) and aberration coefficients were analyzed.Results There were no significant differences in the mean values of RMSG, RMSH, RMS1 to RMS6 (P>0.05) and changes of absolute values of aberration coefficients between baseline and various visits after SCLs discontinuation. However, at d1 after the discontinuation of SCLs, changes in coefficient values of the third-order aberrations (C6 to C9) were slightly higher than others, and C7 was the highest. The increase factors of RMS values were higher at 1 week and lower at the 2 week visit after SCLs discontinuation. The uniformity of dominating type in HOA and the corneal topography form was both about 60% after discontinuation of SCLs. The corneal thickness increased after SCLs wear and gradually decreased to baseline until 1month discontinuation of SCLs.Conclusion The effect of short-term SCLs wear on human ocular aberrations is slight but profound. A month or more wait should be allowed before the short-term SCLs wearers are scheduled for wavefronted-guided LASIK.

  17. Observation of lens aberrations for high resolution electron microscopy II: Simple expressions for optimal estimates

    Energy Technology Data Exchange (ETDEWEB)

    Saxton, W. Owen, E-mail: wos1@cam.ac.uk

    2015-04-15

    This paper lists simple closed-form expressions estimating aberration coefficients (defocus, astigmatism, three-fold astigmatism, coma / misalignment, spherical aberration) on the basis of image shift or diffractogram shape measurements as a function of injected beam tilt. Simple estimators are given for a large number of injected tilt configurations, optimal in the sense of least-squares fitting of all the measurements, and so better than most reported previously. Standard errors are given for most, allowing different approaches to be compared. Special attention is given to the measurement of the spherical aberration, for which several simple procedures are given, and the effect of foreknowledge of this on other aberration estimates is noted. Details and optimal expressions are also given for a new and simple method of analysis, requiring measurements of the diffractogram mirror axis direction only, which are simpler to make than the focus and astigmatism measurements otherwise required. - Highlights: • Optimal estimators for CTEM lens aberrations are more accurate and/or use fewer observations. • Estimators have been found for defocus, astigmatism, three-fold astigmatism, coma and spherical aberration. • Estimators have been found relying on diffractogram shape, image shift and diffractogram orientation only, for a variety of beam tilts. • The standard error for each estimator has been found.

  18. Aberrant innate immune activation following tissue injury impairs pancreatic regeneration.

    Directory of Open Access Journals (Sweden)

    Alexandra E Folias

    development of chronic inflammation arises from aberrant activation of the innate inflammatory response. Collectively these studies identify targetable inflammatory factors that can be used to influence the development of non-resolving inflammation and pancreatic regeneration following injury.

  19. Aberrant gene promoter methylation associated with sporadic multiple colorectal cancer.

    Directory of Open Access Journals (Sweden)

    Victoria Gonzalo

    Full Text Available BACKGROUND: Colorectal cancer (CRC multiplicity has been mainly related to polyposis and non-polyposis hereditary syndromes. In sporadic CRC, aberrant gene promoter methylation has been shown to play a key role in carcinogenesis, although little is known about its involvement in multiplicity. To assess the effect of methylation in tumor multiplicity in sporadic CRC, hypermethylation of key tumor suppressor genes was evaluated in patients with both multiple and solitary tumors, as a proof-of-concept of an underlying epigenetic defect. METHODOLOGY/PRINCIPAL FINDINGS: We examined a total of 47 synchronous/metachronous primary CRC from 41 patients, and 41 gender, age (5-year intervals and tumor location-paired patients with solitary tumors. Exclusion criteria were polyposis syndromes, Lynch syndrome and inflammatory bowel disease. DNA methylation at the promoter region of the MGMT, CDKN2A, SFRP1, TMEFF2, HS3ST2 (3OST2, RASSF1A and GATA4 genes was evaluated by quantitative methylation specific PCR in both tumor and corresponding normal appearing colorectal mucosa samples. Overall, patients with multiple lesions exhibited a higher degree of methylation in tumor samples than those with solitary tumors regarding all evaluated genes. After adjusting for age and gender, binomial logistic regression analysis identified methylation of MGMT2 (OR, 1.48; 95% CI, 1.10 to 1.97; p = 0.008 and RASSF1A (OR, 2.04; 95% CI, 1.01 to 4.13; p = 0.047 as variables independently associated with tumor multiplicity, being the risk related to methylation of any of these two genes 4.57 (95% CI, 1.53 to 13.61; p = 0.006. Moreover, in six patients in whom both tumors were available, we found a correlation in the methylation levels of MGMT2 (r = 0.64, p = 0.17, SFRP1 (r = 0.83, 0.06, HPP1 (r = 0.64, p = 0.17, 3OST2 (r = 0.83, p = 0.06 and GATA4 (r = 0.6, p = 0.24. Methylation in normal appearing colorectal mucosa from patients with multiple and solitary CRC showed no relevant

  20. Weak minimum aberration and maximum number of clear two-factor interactions in 2

    Institute of Scientific and Technical Information of China (English)

    YANG; Guijun

    2005-01-01

    [1]Wu, C. F. J., Chen, Y., A graph-aided method for planning two-level experiments when certain interactions are important, Technometrics, 1992, 34: 162-175.[2]Fries, A., Hunter, W, G., Minimum aberration 2к-p designs, Technometrics, 1980, 22: 601-608.[3]Chen, H., Hedayat, A. S., 2n-l designs with weak minimum aberration, Ann. Statist., 1996, 24: 2536-2548.[4]Chen, J., Some results on 2n-к fractional factorial designs and search for minimum aberration designs, Ann.Statist., 1992, 20: 2124-2141.[5]Chen, J., Intelligent search for 213-6 and 214-7 minimum aberration designs, Statist. Sinica, 1998, 8: 1265-1270.[6]Chen, J., Sun, D. X., Wu, C. F. J., A catalogue of two-level and three-level fractional factorial designs with small runs, Internat. Statist. Rev., 1993, 61: 131-145.[7]Chen, J., Wu, C. F. J., Some results on 2n-к fractional factorial designs with minimum aberration or optimal moments, Ann. Statist., 1991, 19: 1028-1041.[8]Cheng, C. S., Mukerjee, R., Regular fractional factorial designs with minimum aberration and maximum estimation capacity, Ann. Statist., 1998, 26: 2289-2300.[9]Cheng, C. S., Steinberg, D. M., Sun, D. X., Minimum aberration and model robustness for two-level fractional factorial designs, J. Roy. Statist. Soc. Ser. B, 1999, 61: 85-93.[10]Draper, N. R., Lin, D. K. J., Capacity consideration for two-level fractional factorial designs, J. Statist. Plann.Inference, 1990, 24: 25-35.[11]Fang, K. T., Mukerjee, R., A connection between uniformity and aberration in regular fractions of two-level factorial, Biometrika, 2000, 87: 193-198.[12]Tang, B., Wu, C. F. J., Characterization of minimum aberration 2n-к designs in terms of their complementary designs, Ann. Statist., 1996, 24: 2549-2559.[13]Chen, H., Hedayat, A. S., 2n-m designs with resolution Ⅲ or Ⅳ containing clear two-factor interactions, J.Statist. Plann. Inference, 1998, 75: 147-158.[14]Tang, B., Ma, F., Ingram, D., Wang, H., Bounds on the maximum numbers of clear two factor

  1. Deletion of glutamate delta-1 receptor in mouse leads to aberrant emotional and social behaviors.

    Directory of Open Access Journals (Sweden)

    Roopali Yadav

    Full Text Available The delta family of ionotropic glutamate receptors consists of glutamate δ1 (GluD1 and glutamate δ2 (GluD2 receptors. While the role of GluD2 in the regulation of cerebellar physiology is well understood, the function of GluD1 in the central nervous system remains elusive. We demonstrate for the first time that deletion of GluD1 leads to abnormal emotional and social behaviors. We found that GluD1 knockout mice (GluD1 KO were hyperactive, manifested lower anxiety-like behavior, depression-like behavior in a forced swim test and robust aggression in the resident-intruder test. Chronic lithium rescued the depression-like behavior in GluD1 KO. GluD1 KO mice also manifested deficits in social interaction. In the sociability test, GluD1 KO mice spent more time interacting with an inanimate object compared to a conspecific mouse. D-Cycloserine (DCS administration was able to rescue social interaction deficits observed in GluD1 KO mice. At a molecular level synaptoneurosome preparations revealed lower GluA1 and GluA2 subunit expression in the prefrontal cortex and higher GluA1, GluK2 and PSD95 expression in the amygdala of GluD1 KO. Moreover, DCS normalized the lower GluA1 expression in prefrontal cortex of GluD1 KO. We propose that deletion of GluD1 leads to aberrant circuitry in prefrontal cortex and amygdala owing to its potential role in presynaptic differentiation and synapse formation. Furthermore, these findings are in agreement with the human genetic studies suggesting a strong association of GRID1 gene with several neuropsychiatric disorders including schizophrenia, bipolar disorder, autism spectrum disorders and major depressive disorder.

  2. Conjugated linoleic acid supplementation caused reduction of perilipin1 and aberrant lipolysis in epididymal adipose tissue

    International Nuclear Information System (INIS)

    Highlights: ► Conjugated linoleic acid supplementation suppresses perilipin1 in epididymal fat. ► Conjugated linoleic acid inhibits promoter activity of perilipin1 in 3T3-L1 cells. ► Conjugated linoleic acids elevate basal but blunt hormone-stimulated lipolysis. -- Abstract: Perilipin1, a coat protein of lipid droplet, plays a key role in adipocyte lipolysis and fat formation of adipose tissues. However, it is not clear how the expression of perilipin1 is affected in the decreased white adipose tissues (WAT) of mice treated with dietary supplement of conjugated linoleic acids (CLA). Here we obtained lipodystrophic mice by dietary administration of CLA which exhibited reduced epididymal (EPI) WAT, aberrant adipocytes and decreased expression of leptin in this tissue. We found both transcription and translation of perilipin1 was suppressed significantly in EPI WAT of CLA-treated mice compared to that of control mice. The gene expression of negative regulator tumor necrosis factor α (TNFα) and the positive regulator Peroxisome Proliferator-Activated Receptor-γ (PPARγ) of perilipin1 was up-regulated and down-regulated, respectively. In cultured 3T3-L1 cells the promoter activity of perilipin1 was dramatically inhibited in the presence of CLA. Using ex vivo experiment we found that the basal lipolysis was elevated but the hormone-stimulated lipolysis blunted in adipose explants of CLA-treated mice compared to that of control mice, suggesting that the reduction of perilipin1 in white adipose tissues may at least in part contribute to CLA-mediated alternation of lipolysis of WAT.

  3. Conjugated linoleic acid supplementation caused reduction of perilipin1 and aberrant lipolysis in epididymal adipose tissue

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Demin [College of Animal Sciences and Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, Henan Province, People' s Republic of China (China); Li, Hongji [Key Laboratory of Animal Biochemistry and Nutrition, Ministry of Agriculture, Henan Agricultural University, Zhengzhou 450002, Henan Province, People' s Republic of China (China); Zhou, Bo [College of Animal Sciences and Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, Henan Province, People' s Republic of China (China); Han, Liqiang [Key Laboratory of Animal Biochemistry and Nutrition, Ministry of Agriculture, Henan Agricultural University, Zhengzhou 450002, Henan Province, People' s Republic of China (China); Zhang, Xiaomei [College of Animal Sciences and Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, Henan Province, People' s Republic of China (China); Yang, Guoyu, E-mail: haubiochem@163.com [Key Laboratory of Animal Biochemistry and Nutrition, Ministry of Agriculture, Henan Agricultural University, Zhengzhou 450002, Henan Province, People' s Republic of China (China); Yang, Guoqing, E-mail: gqyang@yeah.net [College of Animal Sciences and Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, Henan Province, People' s Republic of China (China)

    2012-06-15

    Highlights: Black-Right-Pointing-Pointer Conjugated linoleic acid supplementation suppresses perilipin1 in epididymal fat. Black-Right-Pointing-Pointer Conjugated linoleic acid inhibits promoter activity of perilipin1 in 3T3-L1 cells. Black-Right-Pointing-Pointer Conjugated linoleic acids elevate basal but blunt hormone-stimulated lipolysis. -- Abstract: Perilipin1, a coat protein of lipid droplet, plays a key role in adipocyte lipolysis and fat formation of adipose tissues. However, it is not clear how the expression of perilipin1 is affected in the decreased white adipose tissues (WAT) of mice treated with dietary supplement of conjugated linoleic acids (CLA). Here we obtained lipodystrophic mice by dietary administration of CLA which exhibited reduced epididymal (EPI) WAT, aberrant adipocytes and decreased expression of leptin in this tissue. We found both transcription and translation of perilipin1 was suppressed significantly in EPI WAT of CLA-treated mice compared to that of control mice. The gene expression of negative regulator tumor necrosis factor {alpha} (TNF{alpha}) and the positive regulator Peroxisome Proliferator-Activated Receptor-{gamma} (PPAR{gamma}) of perilipin1 was up-regulated and down-regulated, respectively. In cultured 3T3-L1 cells the promoter activity of perilipin1 was dramatically inhibited in the presence of CLA. Using ex vivo experiment we found that the basal lipolysis was elevated but the hormone-stimulated lipolysis blunted in adipose explants of CLA-treated mice compared to that of control mice, suggesting that the reduction of perilipin1 in white adipose tissues may at least in part contribute to CLA-mediated alternation of lipolysis of WAT.

  4. Friedreich's ataxia--a case of aberrant transcription termination?

    Science.gov (United States)

    Butler, Jill Sergesketter; Napierala, Marek

    2015-01-01

    Reduced expression of the mitochondrial protein Frataxin (FXN) is the underlying cause of Friedreich's ataxia. We propose a model of premature termination of FXN transcription induced by pathogenic expanded GAA repeats that links R-loop structures, antisense transcription, and heterochromatin formation as a novel mechanism of transcriptional repression in Friedreich's ataxia.

  5. Changes in Monkey Crystalline Lens Spherical Aberration During Simulated Accommodation in a Lens Stretcher

    Science.gov (United States)

    Maceo Heilman, Bianca; Manns, Fabrice; de Castro, Alberto; Durkee, Heather; Arrieta, Esdras; Marcos, Susana; Parel, Jean-Marie

    2015-01-01

    Purpose. The purpose of this study was to quantify accommodation-induced changes in the spherical aberration of cynomolgus monkey lenses. Methods. Twenty-four lenses from 20 cynomolgus monkeys (Macaca fascicularis; 4.4–16.0 years of age; postmortem time 13.5 ± 13.0 hours) were mounted in a lens stretcher. Lens spherical aberration was measured in the unstretched (accommodated) and stretched (relaxed) states with a laser ray tracing system that delivered 51 equally spaced parallel rays along 1 meridian of the lens over the central 6-mm optical zone. A camera mounted below the lens was used to measure the ray height at multiple positions along the optical axis. For each entrance ray, the change in ray height with axial position was fitted with a third-order polynomial. The effective paraxial focal length and Zernike spherical aberration coefficients corresponding to a 6-mm pupil diameter were extracted from the fitted values. Results. The unstretched lens power decreased with age from 59.3 ± 4.0 diopters (D) for young lenses to 45.7 ± 3.1 D for older lenses. The unstretched lens shifted toward less negative spherical aberration with age, from −6.3 ± 0.7 μm for young lenses to −5.0 ± 0.5 μm for older lenses. The power and spherical aberration of lenses in the stretched state were independent of age, with values of 33.5 ± 3.4 D and −2.6 ± 0.5 μm, respectively. Conclusions. Spherical aberration is negative in cynomolgus monkey lenses and becomes more negative with accommodation. These results are in good agreement with the predicted values using computational ray tracing in a lens model with a reconstructed gradient refractive index. The spherical aberration of the unstretched lens becomes less negative with age. PMID:25670492

  6. Transmissive liquid-crystal device correcting primary coma aberration and astigmatism in laser scanning microscopy

    Science.gov (United States)

    Tanabe, Ayano; Hibi, Terumasa; Ipponjima, Sari; Matsumoto, Kenji; Yokoyama, Masafumi; Kurihara, Makoto; Hashimoto, Nobuyuki; Nemoto, Tomomi

    2016-03-01

    Laser scanning microscopy allows 3D cross-sectional imaging inside biospecimens. However, certain aberrations produced can degrade the quality of the resulting images. We previously reported a transmissive liquid-crystal device that could compensate for the predominant spherical aberrations during the observations, particularly in deep regions of the samples. The device, inserted between the objective lens and the microscope revolver, improved the image quality of fixed-mouse-brain slices that were observed using two-photon excitation laser scanning microscopy, which was originally degraded by spherical aberration. In this study, we developed a transmissive device that corrects primary coma aberration and astigmatism, motivated by the fact that these asymmetric aberrations can also often considerably deteriorate image quality, even near the sample surface. The device's performance was evaluated by observing fluorescent beads using single-photon excitation laser scanning microscopy. The fluorescence intensity in the image of the bead under a cover slip tilted in the y-direction was increased by 1.5 times after correction by the device. Furthermore, the y- and z-widths of the imaged bead were reduced to 66% and 65%, respectively. On the other hand, for the imaged bead sucked into a glass capillary in the longitudinal x-direction, correction with the device increased the fluorescence intensity by 2.2 times compared to that of the aberrated image. In addition, the x-, y-, and z-widths of the bead image were reduced to 75%, 53%, and 40%, respectively. Our device successfully corrected several asymmetric aberrations to improve the fluorescent signal and spatial resolution, and might be useful for observing various biospecimens.

  7. Space Radiation Effects on Human Cells: Modeling DNA Breakage, DNA Damage Foci Distribution, Chromosomal Aberrations and Tissue Effects

    Science.gov (United States)

    Ponomarev, A. L.; Huff, J. L.; Cucinotta, F. A.

    2011-01-01

    Future long-tem space travel will face challenges from radiation concerns as the space environment poses health risk to humans in space from radiations with high biological efficiency and adverse post-flight long-term effects. Solar particles events may dramatically affect the crew performance, while Galactic Cosmic Rays will induce a chronic exposure to high-linear-energy-transfer (LET) particles. These types of radiation, not present on the ground level, can increase the probability of a fatal cancer later in astronaut life. No feasible shielding is possible from radiation in space, especially for the heavy ion component, as suggested solutions will require a dramatic increase in the mass of the mission. Our research group focuses on fundamental research and strategic analysis leading to better shielding design and to better understanding of the biological mechanisms of radiation damage. We present our recent effort to model DNA damage and tissue damage using computational models based on the physics of heavy ion radiation, DNA structure and DNA damage and repair in human cells. Our particular area of expertise include the clustered DNA damage from high-LET radiation, the visualization of DSBs (DNA double strand breaks) via DNA damage foci, image analysis and the statistics of the foci for different experimental situations, chromosomal aberration formation through DSB misrepair, the kinetics of DSB repair leading to a model-derived spectrum of chromosomal aberrations, and, finally, the simulation of human tissue and the pattern of apoptotic cell damage. This compendium of theoretical and experimental data sheds light on the complex nature of radiation interacting with human DNA, cells and tissues, which can lead to mutagenesis and carcinogenesis later in human life after the space mission.

  8. Violence in the Hearts of Galaxies - Aberration or Adolescence?

    CERN Document Server

    Mundell, C G

    2002-01-01

    Violent activity in the nuclei of galaxies has long been considered a curiosity in its own right; manifestations of this phenomenon include distant quasars in the early Universe and comparatively nearby Seyfert galaxies, both thought to be powered by the release of gravitational potential energy as material from the host galaxy accretes onto a central supermassive black hole (SMBH). Traditionally, the broader study of the formation, structure and evolution of galaxies has largely excluded active galactic nuclei. Recently however, this situation has changed dramatically, both observationally and theoretically, with the realisation that the growth and influence of the SMBH, the origin and development of galaxies and nuclear activity at different epochs in the Universe may be intimately related. I review the intriguing evidence for causal links between supermassive black holes, nuclear activity and the formation and evolution of galaxies, and describe opportunities for testing these relationships using the next ...

  9. Influence of DMSO on Carbon K ultrasoft X-rays induced chromosome aberrations in V79 Chinese hamster cells

    International Nuclear Information System (INIS)

    Ultrasoft X-rays have been shown to be very efficient in inducing chromosomal aberrations in mammalian cells. The present study was aimed to evaluate the modifying effects of DMSO (a potent scavenger of free radicals) on the frequencies of chromosome aberrations induced by soft X-rays. Confluent held G1 Chinese hamster cells (V79) were irradiated with Carbon K ultrasoft X-rays in the presence and absence of 1 M DMSO and frequencies of chromosome aberrations in the first division cells were determined. DMSO reduced the frequencies of exchange types of aberrations (dicentrics and centric rings) by a factor of 2.1-3.5. The results indicate that free radicals induced by ultrasoft X-rays contribute to a great extent to the induction of chromosome aberrations. The possible implications of these results in interpreting the mechanisms involved in the high efficiency of ultrasoft X-rays in the induction of chromosome aberrations are discussed.

  10. New type of chromosomal aberrations in microspores of Tradescancia Paludosa in flight experiments on board of space satelites

    International Nuclear Information System (INIS)

    A new type of chromosomal aberrations - complex nonreciprocal translocations accompanied by spherical fragments, is opened. The results of 30 variants of tests are investigated to establish what factor particularly causes new type of chromosomal aberrations. The experiments have been carried out on boards the space satelites: ''Vostok 3, 4, 5, 6'', ''Voskhod'', ''Kosmos 110'', ''Zond 6, 7'', ''Kosmos 368''. All type of aberrations have been recorded. It is supposed that a new type of aberrations depends on the effect of the sum of dynamic factors. At the same time these aberrations are not the background and escape it by separate bright bursts being independent on the effect of take-off, landing and time of an object staying in weightlessness. There is a type of irradiation causing a special type of aberrations

  11. Numerical correction of anti-symmetric aberrations in single HRTEM images of weakly scattering 2D-objects

    Energy Technology Data Exchange (ETDEWEB)

    Lehtinen, Ossi, E-mail: ossi.lehtinen@gmail.com [Central Facility for Electron Microscopy, Group of Electron Microscopy of Materials Science, University of Ulm, 89081 Ulm (Germany); Geiger, Dorin; Lee, Zhongbo [Central Facility for Electron Microscopy, Group of Electron Microscopy of Materials Science, University of Ulm, 89081 Ulm (Germany); Whitwick, Michael Brian; Chen, Ming-Wei; Kis, Andras [Electrical Engineering Institute, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland); Kaiser, Ute [Central Facility for Electron Microscopy, Group of Electron Microscopy of Materials Science, University of Ulm, 89081 Ulm (Germany)

    2015-04-15

    Here, we present a numerical post-processing method for removing the effect of anti-symmetric residual aberrations in high-resolution transmission electron microscopy (HRTEM) images of weakly scattering 2D-objects. The method is based on applying the same aberrations with the opposite phase to the Fourier transform of the recorded image intensity and subsequently inverting the Fourier transform. We present the theoretical justification of the method, and its verification based on simulated images in the case of low-order anti-symmetric aberrations. Ultimately the method is applied to experimental hardware aberration-corrected HRTEM images of single-layer graphene and MoSe{sub 2} resulting in images with strongly reduced residual low-order aberrations, and consequently improved interpretability. Alternatively, this method can be used to estimate by trial and error the residual anti-symmetric aberrations in HRTEM images of weakly scattering objects.

  12. miRNA gene promoters are frequent targets of aberrant DNA methylation in human breast cancer.

    Science.gov (United States)

    Vrba, Lukas; Muñoz-Rodríguez, José L; Stampfer, Martha R; Futscher, Bernard W

    2013-01-01

    miRNAs are important regulators of gene expression that are frequently deregulated in cancer, with aberrant DNA methylation being an epigenetic mechanism involved in this process. We previously identified miRNA promoter regions active in normal mammary cell types and here we analyzed which of these promoters are targets of aberrant DNA methylation in human breast cancer cell lines and breast tumor specimens. Using 5-methylcytosine immunoprecipitation coupled to miRNA tiling microarray hybridization, we performed comprehensive evaluation of DNA methylation of miRNA gene promoters in breast cancer. We found almost one third (55/167) of miRNA promoters were targets for aberrant methylation in breast cancer cell lines. Breast tumor specimens displayed DNA methylation of majority of these miRNA promoters, indicating that these changes in DNA methylation might be clinically relevant. Aberrantly methylated miRNA promoters were, similar to protein coding genes, enriched for promoters targeted by polycomb in normal cells. Detailed analysis of selected miRNA promoters revealed decreased expression of miRNA linked to increased promoter methylation for mir-31, mir-130a, let-7a-3/let-7b, mir-155, mir-137 and mir-34b/mir-34c genes. The proportion of miRNA promoters we found aberrantly methylated in breast cancer is several fold larger than that observed for protein coding genes, indicating an important role of DNA methylation in miRNA deregulation in cancer.

  13. Combining Chromosomal Arm Status and Significantly Aberrant Genomic Locations Reveals New Cancer Subtypes

    Directory of Open Access Journals (Sweden)

    Tal Shay

    2009-01-01

    Full Text Available Many types of tumors exhibit characteristic chromosomal losses or gains, as well as local amplifications and deletions. Within any given tumor type, sample specific amplifications and deletions are also observed. Typically, a region that is aberrant in more tumors, or whose copy number change is stronger, would be considered as a more promising candidate to be biologically relevant to cancer. We sought for an intuitive method to define such aberrations and prioritize them. We define V, the “volume” associated with an aberration, as the product of three factors: (a fraction of patients with the aberration, (b the aberration’s length and (c its amplitude. Our algorithm compares the values of V derived from the real data to a null distribution obtained by permutations, and yields the statistical significance (p-value of the measured value of V. We detected genetic locations that were significantly aberrant, and combine them with chromosomal arm status (gain/loss to create a succinct fingerprint of the tumor genome. This genomic fingerprint is used to visualize the tumors, highlighting events that are co-occurring or mutually exclusive. We apply the method on three different public array CGH datasets of Medulloblastoma and Neuroblastoma, and demonstrate its ability to detect chromosomal regions that were known to be altered in the tested cancer types, as well as to suggest new genomic locations to be tested. We identified a potential new subtype of Medulloblastoma, which is analogous to Neuroblastoma type 1.

  14. The use of unstable chromosome aberrations and micronuclei in the individual biomonitoring: a comparative study

    International Nuclear Information System (INIS)

    Biodosimetry is based on the investigation of radioinduced biological effects in order to correlate them with the absorbed dose. The quantification of unstable chromosome aberrations and micronuclei, in peripheral blood lymphocytes, are two methods commonly used in biodosimetry. In this context, the aim of this research was to compare these methods in the biomonitoring of health care professionals occupationally exposed to ionizing radiation. In parallel, the technique of C-banding was evaluated for quality control of unstable chromosome aberrations analyses. Thus, samples of peripheral blood from health care professionals of three hospitals from Recife (Brazil) were collected, and the lymphocytes cultures were carried out based on the cytogenetic classical technique. It was pointed out that analysis of micronuclei is faster than the unstable chromosome aberrations ones, which suggests the use of the former in preliminary evaluation in cases of suspected accidental exposure. C-banding technique was efficient, as confirmatory test, in the identification of dicentrics and rings during the analyses of unstable chromosome aberrations, being able to be applied in the quality control in biodosimetry. The comparison between the individual work conditions with the frequencies of unstable aberrations and micronuclei obtained from cytogenetic analysis, resulted in the change of behavior of the professionals involved in this research, with a better observance of the radioprotection standards. (author)

  15. Mechanisms of induction of chromosomal aberrations and their detection by fluorescence in situ hybridization

    International Nuclear Information System (INIS)

    Recently introduced fluorescence in situ hybridization (FISH) technique employing chromosome specific DNA libraries as well as region specific DNA probes (e.g., centromere, telomere) have helped to analyse chromosomal aberrations in great detail and thus have given some new insights into the mechanisms of induction of chromosomal aberrations. The relative proportion of induction of translocations and dicentrics by ionising radiation was studied in human, mice and Chinese hamster cells. Many of the studies point to the differences between the mechanisms of induction of dicentrics and translocations. Preliminary results obtained in our laboratory using arm specific probes for human chromosomes 1 and 3 indicate that the aberrations between the arms appear to be more than expected on a random basis. By employing telomeric probes the frequencies of interstitial deletions were found to be high and similar to the frequencies of dicentrics both in human and mouse lymphocytes. A recent study with human chromosome specific probes clearly shows variation of sensitivity of chromosomes for the induction of exchange aberrations. Radiation response studies with Chinese hamster cells using telomeric probes, suggest that telomeric sequences, especially interstitial ones appear to be an important factor in the origin of both spontaneous and induced chromosomal aberrations

  16. The prevalence of chromosomal aberrations associated with myelodysplastic syndromes in China.

    Science.gov (United States)

    Hu, Qinyong; Chu, Yuxin; Song, Qibin; Yao, Yi; Yang, Weihong; Huang, Shiang

    2016-08-01

    This study aims to investigate the prevalence and distribution of diverse chromosomal aberrations associated with myelodysplastic syndromes (MDS) in China. Bone marrow samples were collected from multiple cities in China. Metaphase cytogenetic (MC) analysis and fluorescence in situ hybridization (FISH) were initially used to test chromosomal lesions. Affymetrix CytoScan 750 K genechip platform performed a genome-wide detection of chromosomal aberrations. Chromosomal gain was identified in 76 patients; the most prevalent was trisomy 8(17.9 %). New chromosomal gain was detected on chromosome 9, 19p, and X. Chromosomal loss was detected in 101 patients. The most frequent was loss 5q (21.0 %). Some loss and gain were not identified by MC or FISH but identified by genechip. UPD was solely identified by genechip in 51 patients; the most prevalent were UPD 7q (4.94 %) and UPD 17p (4.32 %). Furthermore, complex chromosomal aberrations were detected in 56 patients. In conclusion, Affymetrix CytoScan 750 K genechip was more precise than MC and FISH in detection of cryptic chromosomal aberrations relevant to MDS. Analysis of the prevalence and distribution of diverse chromosomal aberrations in China may improve strategies for MDS diagnosis and therapies. PMID:27225263

  17. Effects of aberration on paraxial wave beams: beam tracing versus quasi-optical solutions

    Energy Technology Data Exchange (ETDEWEB)

    Maj, O [Max-Planck-Institut fuer Sonnensystemforschung, Katlenburg-Lindau (Germany); Balakin, A A [Institute of Applied Physics RAS, Nizhny Novgorod (Russian Federation); Poli, E, E-mail: omaj@ipp.mpg.d [Max-Planck-Institut fuer Plasmaphysik, Garching bei Muenchen (Germany)

    2010-08-15

    This paper aims to clarify the role of aberration effects on the propagation and absorption of wave beams in inhomogeneous dispersive and dissipative media. We consider models in which aberration effects can be caused by the presence of either caustics or spatially dispersive absorption, with reference to the propagation near a cut-off or to the electron-cyclotron (EC) resonance, respectively. For such models, the standard beam tracing description of paraxial wave beams and the recently proposed quasi-optical method, which accounts for aberration, are compared and verified on the basis of the analytical exact solutions. We find that the presence of a cut-off implies no significant aberration of the beam, while significant aberration is found when dispersive absorption is so strong that different wavenumbers in the beam spectrum are damped at different locations. This phenomenon is well described by the quasi-optical method. Finally, an extrapolation of this simple two-dimensional model to the case of the ITER upper EC port is addressed with the result that the broadening of the power deposition profiles never exceeds 10%.

  18. Aberrant histone H4 acetylation in dead somatic cell-cloned calves

    Institute of Scientific and Technical Information of China (English)

    Lei Zhang; Shaohua Wang; Qiang Li; Xiangdong Ding; Yunping Dai; Ning Li

    2008-01-01

    In somatic cell-cloned animals, inefficient epigenetic reprogramming can result in an inappropriate gene expression and histone H4 acetylation is one of the key epigenetic modifications regulating gene expression. In this study, we investigated the levels of histone H4 acetylation of 11 development-related genes and expression levels of 19 genes in lungs of three normal control calves and nine aber-rant somatic cell-cloned calves. The results showed that nine studied genes had decreased acetylation levels in aberrant clones (p 0.05). Whereas 13 genes had significantly decreased expression (p 0.05), and only one gene had higher expression level in clones (p < 0.05). Furthermore, FGFR, GHR, HGFR and IGF1 genes showed lowered levels of both histone H4 acetylation and expression in aberrant clones than in controls, and the level of histone H4 acetylation was even more lowered in aberrant clones than those in controls. It was suggested that the lower levels of histone H4 acetylation in aberrant clones caused by the previous memory of cell differentiation might not support enough chromatin reprogramming, thus affecting appropriate gene expressions, and growth and development of the cloned calves. To our knowledge, this is the first study on how histone H4 acetylation affects gene expression in organs of somatic cell-cloned calves.

  19. Comparison between two different methods to obtain the wavefront aberration function

    Science.gov (United States)

    Cruz Félix, Angel S.; Ibarra, Jorge; López, Estela; Rosales, Marco A.; Tepichín, Eduardo

    2010-08-01

    The analysis and measurement of the wavefront aberration function are very important tools that allow us to evaluate the performance of any specified optical system. This technology has been adopted in visual optics for the analysis of optical aberrations in the human eye, before and after being subjected to laser refractive surgery. We have been working in the characterization and evaluation of the objective performance of human eyes that have been subjected to two different surface ablation techniques known as ASA and PASA1. However, optical aberrations in the human eye are time-dependent2 and, hence, difficult to analyze. In order to obtain a static profile from the post-operatory wavefront aberration function we applied these ablation techniques directly over hard contact lenses. In this work we show the comparison between two different methods to obtain the wavefront aberration function from a reference refractive surface, in order to generalize this method and being able to fully characterize hard contact lenses which have been subjected to different ablation techniques typically used in refractive surgery for vision correction. For the first method we used a Shack-Hartmann wavefront sensor, and in the second method we used a Mach-Zehnder type interferometer. We show the preliminary results of this characterization.

  20. Stellar formation

    CERN Document Server

    Reddish, V C

    1978-01-01

    Stellar Formation brings together knowledge about the formation of stars. In seeking to determine the conditions necessary for star formation, this book examines questions such as how, where, and why stars form, and at what rate and with what properties. This text also considers whether the formation of a star is an accident or an integral part of the physical properties of matter. This book consists of 13 chapters divided into two sections and begins with an overview of theories that explain star formation as well as the state of knowledge of star formation in comparison to stellar structure

  1. Characterization of Mannheimia haemolytica biofilm formation in vitro.

    Science.gov (United States)

    Boukahil, Ismail; Czuprynski, Charles J

    2015-01-30

    Mannheimia haemolytica is the primary bacterial agent in the bovine respiratory disease complex. It is thought that M. haemolytica colonizes the tonsillar crypts of cattle as a commensal and subsequently descends into the lungs to cause disease. Many bacterial species persist in the host as biofilms. There is limited information about the ability of M. haemolytica to form biofilms. The aim of this study was to develop an in vitro model for M. haemolytica biofilm formation. We found that M. haemolytica required at least 36 h to form robust biofilms on plastic in vitro when incubated in RPMI-1640 tissue culture medium at 37 °C, with maximal biofilm formation being evident at 48 h. Biofilm formation was inhibited by adding the monosaccharides d(+) galactose and d(+) mannose to the growth medium. Addition of antibodies to the M. haemolytica surface protein OmpA also reduced biofilm formation. Upon evaluating the macromolecules within the biofilm extracellular polymeric substance we found it contained 9.7 μg/cm(2) of protein, 0.81 μg/cm(2) of total carbohydrate, and 0.47 μg/cm(2) of extracellular DNA. Furthermore, proteinase K treatment significantly decreased biofilms (Pbiofilms to a lesser extent. M. haemolytica biofilm cells were more resistant than planktonic cells to the antibiotics florfenicol, gentamicin, and tulathromycin. These results provide evidence that M. haemolytica can form biofilms, which could contribute to its ability to persist as a commensal in the bovine upper respiratory tract.

  2. Galaxy formation

    International Nuclear Information System (INIS)

    Galaxy formation is at the forefront of observation and theory in cosmology. An improved understanding is essential for improving our knowledge both of the cosmological parameters, of the contents of the universe, and of our origins. In these lectures intended for graduate students, galaxy formation theory is reviewed and confronted with recent observational issues. In lecture 1, the following topics are presented: star formation considerations, including IMF, star formation efficiency and star formation rate, the origin of the galaxy luminosity function, and feedback in dwarf galaxies. In lecture 2, we describe formation of disks and massive spheroids, including the growth of supermassive black holes, negative feedback in spheroids, the AGN-star formation connection, star formation rates at high redshift and the baryon fraction in galaxies.

  3. Galaxy formation

    CERN Document Server

    Silk, Joseph; Dvorkin, Irina

    2015-01-01

    Galaxy formation is at the forefront of observation and theory in cosmology. An improved understanding is essential for improving our knowledge both of the cosmological parameters, of the contents of the universe, and of our origins. In these lectures intended for graduate students, galaxy formation theory is reviewed and confronted with recent observational issues. In Lecture 1, the following topics are presented: star formation considerations, including IMF, star formation efficiency and star formation rate, the origin of the galaxy luminosity function, and feedback in dwarf galaxies. In Lecture 2, we describe formation of disks and massive spheroids, including the growth of supermassive black holes, negative feedback in spheroids, the AGN-star formation connection, star formation rates at high redshift and the baryon fraction in galaxies.

  4. Effect of epithalon on the incidence of chromosome aberrations in senescence-accelerated mice.

    Science.gov (United States)

    Rosenfeld, S V; Togo, E F; Mikheev, V S; Popovich, I G; Khavinson, V Kh; Anisimov, V N

    2002-03-01

    The incidence of chromosome aberrations in bone marrow cells of 12-month-old SAMP-1 female mice characterized by accelerated aging was 1.8 times higher than in wild-type SAMR-1 females and 2.2 times higher than in SHR females of the same age. Treatment with Epithalon (Ala-Glu-Asp-Gly) starting from the age of 2 months decreased the incidence of chromosome aberrations in SAMP-1, SAMR-1, and SHR mice by 20%, 30.1%, and 17.9%, respectively, compared to age-matched controls (p<0.05). Treatment with melatonin (given with drinking water in a dose of 20 mg/liter in night hours) had no effect on the incidence of chromosome aberrations in SHR mice. These data indicate antimutagenic effect of Epithalon, which probably underlies the geroprotective effect of this peptide. PMID:12360351

  5. An aberrant vascular channel in the petrous bone: persistent lateral capital vein?

    Energy Technology Data Exchange (ETDEWEB)

    Hermans, Robert [University Hospitals Leuven, Department of Radiology, Leuven (Belgium); Rensburg, Leon J. van [University of the Western Cape, Department of Radiology and Diagnostics, Tygerberg (South Africa)

    2009-12-15

    An aberrant channel was identified on CT in the petrous bone in four patients presenting with unrelated otological symptoms. These channels occurred unilaterally in each case. In two patients, the channel was seen to run between the sigmoid sinus sulcus and the superior petrosal sinus sulcus; in one of these patients, a vascular structure was identified within this channel on MRI, connecting the sigmoid sinus and the superior petrosal sinus. In the two other patients, an aberrant channel was seen between the superior petrosal sinus sulcus and the posterior genu of the facial nerve canal. There were no symptoms that could be attributed to the presence of these channels. We postulate that these aberrant vascular channels correspond to a persistent embryological vein, the lateral capital vein. (orig.)

  6. Aberrant Promoter Hypomethylation in CLL: Does It Matter for Disease Development?

    Science.gov (United States)

    Upchurch, Garland Michael; Haney, Staci L.; Opavsky, Rene

    2016-01-01

    Over the last 30 years, studies of aberrant DNA methylation in hematologic malignancies have been dominated by the primary focus of understanding promoter hypermethylation. These efforts not only resulted in a better understanding of the basis of epigenetic silencing of tumor suppressor genes but also resulted in approval of hypomethylating agents for the treatment of several malignancies, such as myelodysplastic syndrome and acute myeloid leukemia. Recent advances in global methylation profiling coupled with the use of mouse models suggest that aberrant promoter hypomethylation is also a frequent event in hematologic malignancies, particularly in chronic lymphocytic leukemia (CLL). Promoter hypomethylation affects gene expression and, therefore, may play an important role in disease pathogenesis. Here, we review recent findings and discuss the potential involvement of aberrant promoter hypomethylation in CLL. PMID:27563627

  7. Correcting for color crosstalk and chromatic aberration in multicolor particle shadow velocimetry

    International Nuclear Information System (INIS)

    Color crosstalk and chromatic aberration can bias estimates of fluid velocity measured by color particle shadow velocimetry (CPSV), using multicolor illumination and a color camera. This article describes corrections to remove these bias errors, and their evaluation. Color crosstalk removal is demonstrated with linear unmixing. It is also shown that chromatic aberrations may be removed using either scale calibration, or by processing an image illuminated by all colors simultaneously. CPSV measurements of a fully developed turbulent pipe flow of glycerin were conducted. Corrected velocity statistics from these measurements were compared to both single-color PSV and LDV measurements and showed excellent agreement to fourth-order, to well into the viscous sublayer. Recommendations for practical assessment and correction of color aberration and color crosstalk are discussed. (paper)

  8. Exploring the depth range for three-dimensional laser machining with aberration correction.

    Science.gov (United States)

    Salter, P S; Baum, M; Alexeev, I; Schmidt, M; Booth, M J

    2014-07-28

    The spherical aberration generated when focusing from air into another medium limits the depth at which ultrafast laser machining can be accurately maintained. We investigate how the depth range may be extended using aberration correction via a liquid crystal spatial light modulator (SLM), in both single point and parallel multi-point fabrication in fused silica. At a moderate numerical aperture (NA = 0.5), high fidelity fabrication with a significant level of parallelisation is demonstrated at the working distance of the objective lens, corresponding to a depth in the glass of 2.4 mm. With a higher numerical aperture (NA = 0.75) objective lens, single point fabrication is demonstrated to a depth of 1 mm utilising the full NA, and deeper with reduced NA, while maintaining high repeatability. We present a complementary theoretical model that enables prediction of the effectiveness of SLM based correction for different aberration magnitudes.

  9. Adaptive, spatially-varying aberration correction for real-time holographic projectors.

    Science.gov (United States)

    Kaczorowski, Andrzej; Gordon, George S D; Wilkinson, Timothy D

    2016-07-11

    A method of generating an aberration- and distortion-free wide-angle holographically projected image in real time is presented. The target projector is first calibrated using an automated adaptive-optical mechanism. The calibration parameters are then fed into the hologram generation program, which applies a novel piece-wise aberration correction algorithm. The method is found to offer hologram generation times up to three orders of magnitude faster than the standard method. A projection of an aberration- and distortion-free image with a field of view of 90x45 degrees is demonstrated. The implementation on a mid-range GPU achieves high resolution at a frame rate up to 12fps. The presented methods are automated and can be performed on any holographic projector. PMID:27410846

  10. Measuring chromatic aberrations in imaging systems using plasmonic nano-particles

    CERN Document Server

    Gennaro, Sylvain D; Maier, Stefan A; Oulton, Rupert F

    2015-01-01

    Chromatic aberration in optical systems arises from the wavelength dependence of a glass's refractive index. Polychromatic rays incident upon an optical surface are refracted at slightly different angles and in traversing an optical system follow distinct paths creating images displaced according to color. Although arising from dispersion, it manifests as a spatial distortion correctable only with compound lenses with multiple glasses and accumulates in complicated imaging systems. While chromatic aberration is measured with interferometry, simple methods are attractive for their ease of use and low cost. In this letter we retrieve the longitudinal chromatic focal shift of high numerical aperture (NA) microscope objectives from the extinction spectra of metallic nanoparticles within the focal plane. The method is accurate for high NA objectives with apochromatic correction, and enables rapid assessment of the chromatic aberration of any complete microscopy systems, since it is straightforward to implement

  11. Chromosome aberrations induced in human lymphocytes by U-235 fission neutrons. Pt. 2

    International Nuclear Information System (INIS)

    Blood samples were spiked with Na-24 to study the separate effect of this nuclide on the incidence of chromosomal aberrations in neutron irradiated blood samples. A delay of 96 h was allowed before cultivation, so the results of chromosomal aberration analysis could be compared with the results obtained by direct irradiation of blood samples with U-235 fission neutrons. The absorbed dose was calculated using a simple conservative model. From the results obtained we can conclude that Na-24 alone was not the reason for the difference in the incidence of chromosomal aberrations between blood samples cultivated immediately after 'in vitro' irradiation by U-235 fission neutrons and samples which were cultivated after 96 h storage. (orig.)

  12. DNA Copy Number Aberrations in Breast Cancer by Array Comparative Genomic Hybridization

    Institute of Scientific and Technical Information of China (English)

    Jian Li; Kai Wang; Shengting Li; Vera Timmermans-Wielenga; Fritz Rank; Carsten Wiuf; Xiuqing Zhang; Huanming Yang; Lars Bolund

    2009-01-01

    Array comparative genomic hybridization (CGH) has been popularly used for an-alyzing DNA copy number variations in diseases like cancer. In this study, we investigated 82 sporadic samples from 49 breast cancer patients using 1-Mb reso-lution bacterial artificial chromosome CGH arrays. A number of highly frequent genomic aberrations were discovered, which may act as "drivers" of tumor pro-gression. Meanwhile, the genomic profiles of four "normal" breast tissue samples taken at least 2 cm away from the primary tumor sites were also found to have some genomic aberrations that recurred with high frequency in the primary tu-mors, which may have important implications for clinical therapy. Additionally, we performed class comparison and class prediction for various clinicopathological pa-rameters, and a list of characteristic genomic aberrations associated with different clinicopathological phenotypes was compiled. Our study provides clues for further investigations of the underlying mechanisms of breast carcinogenesis.

  13. Generalized ray-transfer matrix for an optical element having an arbitrary wavefront aberration.

    Science.gov (United States)

    Jeong, Tae Moon; Ko, Do-Kyeong; Lee, Jongmin

    2005-11-15

    A generalized ray-transfer matrix for describing the action of an optical element having an arbitrary wavefront aberration is obtained. In this generalized ray-transfer matrix, the action of the aberrated optical element is represented by the product of radial ray-transfer matrices and tangential ray-transfer matrices. The refraction angle of an incident ray is calculated from the gradient of the wavefront aberration at the point of incidence, and the radial and tangential ray-transfer matrices directly use the gradient as a matrix component. To show the validity of the generalized ray-transfer matrix, intercept heights from a spot diagram are calculated with the generalized ray-transfer matrix and compared with those calculated with commercial ray-tracing software.

  14. Aberrant “Barbed-Wire” Nuclear Projections of Neutrophils in Trisomy 18 (Edwards Syndrome

    Directory of Open Access Journals (Sweden)

    Basil M. Kahwash

    2015-01-01

    Full Text Available We discuss the significance of neutrophils with increased, aberrant nuclear projections mimicking “barbed-wire” in a newborn child with trisomy 18 (T18. Increased, aberrant nuclear projections have been previously reported in trisomy of the D group of chromosomes (chromosomes 13, 14, and 15, and we report similar findings in a patient with T18. The peripheral blood smear showed relative neutrophilia with the majority (37% of neutrophils showing two or more thin, rod-shaped or spike-shaped, and often pedunculated aberrant nuclear projections. The number of projections ranged from 2 to 6 per cell, averaged 2 per affected neutrophil, and ranged in length from 0.22 μm to 0.83 μm. This case confirms that the morphologic finding described is not restricted to trisomy of one of the chromosomes in group D, as implied in the literature.

  15. Investigating the influence of chromatic aberration and optical illumination bandwidth on fundus imaging in rats

    Science.gov (United States)

    Li, Hao; Liu, Wenzhong; Zhang, Hao F.

    2015-10-01

    Rodent models are indispensable in studying various retinal diseases. Noninvasive, high-resolution retinal imaging of rodent models is highly desired for longitudinally investigating the pathogenesis and therapeutic strategies. However, due to severe aberrations, the retinal image quality in rodents can be much worse than that in humans. We numerically and experimentally investigated the influence of chromatic aberration and optical illumination bandwidth on retinal imaging. We confirmed that the rat retinal image quality decreased with increasing illumination bandwidth. We achieved the retinal image resolution of 10 μm using a 19 nm illumination bandwidth centered at 580 nm in a home-built fundus camera. Furthermore, we observed higher chromatic aberration in albino rat eyes than in pigmented rat eyes. This study provides a design guide for high-resolution fundus camera for rodents. Our method is also beneficial to dispersion compensation in multiwavelength retinal imaging applications.

  16. Aberrant overian artery originating from the Ilolumbar artery: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Eun; Lee, Jae Myeong [Dept. of Radiology, Soonchunhyang University College of Medicine, Bucheon Hospital, Bucheon (Korea, Republic of)

    2016-05-15

    Here, we report a case of a 30-year-old woman who presented with primary postpartum hemorrhage due to uterine atony. She received uterine artery embolization (UAE). During left internal iliac arteriography, an aberrant left ovarian artery originating from the left iliolumbar artery was visualized. The aberrant left ovarian artery was connected to the left uterine artery via prominent collateral vessels. It supplied a significant amount of blood to the fundus of the uterus. Bilateral hypertrophied uterine arteries were embolized very carefully so that the embolic material did not reflux into the aberrant left ovarian artery. After the procedure, her vaginal bleeding was successfully controlled. Accurate understanding of anatomical variations of the ovarian artery is essential to avoid failure in controlling postpartum hemorrhage with UAE.

  17. Computational genes: a tool for molecular diagnosis and therapy of aberrant mutational phenotype

    Directory of Open Access Journals (Sweden)

    Ignatova Zoya

    2007-09-01

    Full Text Available Abstract Background A finite state machine manipulating information-carrying DNA strands can be used to perform autonomous molecular-scale computations at the cellular level. Results We propose a new finite state machine able to detect and correct aberrant molecular phenotype given by mutated genetic transcripts. The aberrant mutations trigger a cascade reaction: specific molecular markers as input are released and induce a spontaneous self-assembly of a wild type protein or peptide, while the mutational disease phenotype is silenced. We experimentally demostrated in in vitro translation system that a viable protein can be autonomously assembled. Conclusion Our work demostrates the basic principles of computational genes and particularly, their potential to detect mutations, and as a response thereafter administer an output that suppresses the aberrant disease phenotype and/or restores the lost physiological function.

  18. Zero-inflated regression models for radiation-induced chromosome aberration data: A comparative study.

    Science.gov (United States)

    Oliveira, María; Einbeck, Jochen; Higueras, Manuel; Ainsbury, Elizabeth; Puig, Pedro; Rothkamm, Kai

    2016-03-01

    Within the field of cytogenetic biodosimetry, Poisson regression is the classical approach for modeling the number of chromosome aberrations as a function of radiation dose. However, it is common to find data that exhibit overdispersion. In practice, the assumption of equidispersion may be violated due to unobserved heterogeneity in the cell population, which will render the variance of observed aberration counts larger than their mean, and/or the frequency of zero counts greater than expected for the Poisson distribution. This phenomenon is observable for both full- and partial-body exposure, but more pronounced for the latter. In this work, different methodologies for analyzing cytogenetic chromosomal aberrations datasets are compared, with special focus on zero-inflated Poisson and zero-inflated negative binomial models. A score test for testing for zero inflation in Poisson regression models under the identity link is also developed. PMID:26461836

  19. Measuring aberrations in the rat brain by coherence-gated wavefront sensing using a Linnik interferometer.

    Science.gov (United States)

    Wang, Jinyu; Léger, Jean-François; Binding, Jonas; Boccara, A Claude; Gigan, Sylvain; Bourdieu, Laurent

    2012-10-01

    Aberrations limit the resolution, signal intensity and achievable imaging depth in microscopy. Coherence-gated wavefront sensing (CGWS) allows the fast measurement of aberrations in scattering samples and therefore the implementation of adaptive corrections. However, CGWS has been demonstrated so far only in weakly scattering samples. We designed a new CGWS scheme based on a Linnik interferometer and a SLED light source, which is able to compensate dispersion automatically and can be implemented on any microscope. In the highly scattering rat brain tissue, where multiply scattered photons falling within the temporal gate of the CGWS can no longer be neglected, we have measured known defocus and spherical aberrations up to a depth of 400 µm.

  20. Proton and Fe Ion-Induced Early and Late Chromosome Aberrations in Different Cell Types

    Science.gov (United States)

    Lu, Tao; Zhang, Ye; Yeshitla, Samrawit; Bowler, Deborah; Kadhim, Munira; Wilson, Bobby; Wu, Honglu

    2016-01-01

    Genomic instability, induced by various metabolic, genetic, and environmental factors, is the driving force of tumorigenesis. Radiation exposure from different types of radiation sources induces different types of DNA damages, increases mutation and chromosome aberration rates, and increases cellular transformation in vitro and in vivo experiments. The cell survival rates and frequency of chromosome aberrations depend on the genetic background and radiation sources. To further understand genomic instability induced by charged particles, we exposed human lymphocytes ex vivo, human fibroblast cells, human mammary epithelial cells, and bone marrow cells isolated from CBA/CaH and C57BL/6 mice to high energy protons and Fe ions, and collected chromosomes at different generations after exposure. Chromosome aberrations were analyzed with fluorescent in situ hybridization with whole chromosome specific probes.