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41.
Petek E Pertl B Tschernigg M Bauer M Mayr J Wagner K Kroisel PM 《Genetic counseling (Geneva, Switzerland)》2003,14(2):239-244
Trisomy 18 is the second most frequent autosomal aneuploidy affecting about 1 in 8,000 new-borns. Similar to trisomy 13 more than 90% of the patients die within the first year. Main causes of death are failure of vital organ function, in most cases of brain, heart, kidney, and gut, sometimes combined with severe infections. The degree to which essential organs are affected at birth and the clinical course differ considerably. Unknown genetic factors and various environmental effects are most likely involved. A less severe course of Edwards syndrome can be caused by a partial trisomy due to a deletion of the extra chromosome 18 or somatic mosaicism with a trisomic and a normal cell-line in the patient. In this report conventional chromosome analysis, FISH, and QF-PCR have been performed on a 19-year-old female patient with trisomy 18 to investigate a large number of cells including non-mitotic cells from various different tissues. This study supports evidence for an apparently pure form of trisomy 18 in this "long-living" patient with Edwards syndrome. 相似文献
42.
Food Biophysics - Engineered biocatalyst and its desired products using nanotechnology has intensified the research in food industries. Zinc oxide (ZnO) nanosheet is designed and prepared; the... 相似文献
43.
Jo Moore Stephen AC Hawkins Anthony R Austin Timm Konold Robert B Green Ian W Blamire Ian Dexter Michael J Stack Melanie J Chaplin Jan PM Langeveld Marion M Simmons Yvonne I Spencer Paul R Webb Michael Dawson Gerald AH Wells 《BMC research notes》2011,4(1):1-13
Background
Escherichia coli O157:H7 is the most common serovar of enterohemorrhagic E. coli associated with serious human disease outbreaks. Cattle are the main reservoir with E. coli O157:H7 inducing hemorrhagic enteritis in persistent shedding beef cattle, however little is known about how this pathogen affects cattle health. Jejunal Hemorrhage Syndrome (JHS) has unclear etiology but the pathology is similar to that described for E. coli O157:H7 challenged beef cattle suggestive that E. coli O157:H7 could be involved. There are no effective treatments for JHS however new approaches to managing pathogen issues in livestock using prebiotics and probiotics are gaining support. The first objective of the current study was to characterize pathogen colonization in hemorrhaged jejunum of dairy cattle during natural JHS outbreaks. The second objective was to confirm the association of mycotoxigenic fungi in feeds with the development of JHS and also to identify the presence of potential mycotoxins. The third objective was to determine the impact of a prebiotic, Celmanax?, or probiotic, Dairyman's Choice? paste, on the cytotoxicity associated with feed extracts in vitro. The fourth objective was to determine the impact of a prebiotic or a probiotic on E. coli O157:H7 colonization of mucosal explants and a bovine colonic cell line in vitro. The final objective was to determine if prebiotic and probiotic feed additives could modify the symptoms that preceded JHS losses and the development of new JHS cases.Findings
Dairy cattle developed JHS after consuming feed containing several types of mycotoxigenic fungi including Fusarium culmorum, F. poae, F. verticillioides, F. sporotrichioides, Aspergillus flavus, Penicillium roqueforti, P. crustosum, P. paneum and P. citrinum. Mixtures of Shiga toxin - producing Escherichia coli (STEC) colonized the mucosa in the hemorrhaged tissues of the cattle and no other pathogen was identified. The STECs expressed Stx1 and Stx2, but more significantly, Stxs were also present in the blood clot blocking the jejunum. Mycotoxin analysis of the corn crop confirmed the presence of fumonisin, NIV, ZEAR, DON, 15-ADON, 3-ADON, NEO, DAS, HT-2 and T-2. Feed extracts were toxic to enterocytes and 0.1% Celmanax? removed the cytotoxicity in vitro. There was no effect of Dairyman's Choice? paste on feed-extract activity in vitro. Fumonisin, T-2, ZEAR and DON were toxic to bovine cells and 0.1% Celmanax? removed the cytotoxicity in vitro. Celmanax? also directly decreased E. coli O157:H7 colonization of mucosal explants and a colonic cell line in a dose-dependent manner. There was no effect of Dairyman's Choice? paste on E. coli O157:H7 colonization in vitro. The inclusion of the prebiotic and probiotic in the feed was associated with a decline in disease.Conclusion
The current study confirmed an association between mycotoxigenic fungi in the feed and the development of JHS in cattle. This association was further expanded to include mycotoxins in the feed and mixtures of STECs colonizing the severely hemorrhaged tissues. Future studies should examine the extent of involvement of the different STEC in the infection process. The prebiotic, Celmanax?, acted as an anti-adhesive for STEC colonization and a mycotoxin binder in vitro. Future studies should determine the extent of involvement of the prebiotic in altering disease. 相似文献44.
45.
Molecular and cytogenetic analysis in two patients with microdeletions of 7p and Greig syndrome: hemizygosity for PGAM2 and TCRG genes 总被引:2,自引:0,他引:2
Greig cephalopolysyndactyly syndrome (GCPS) is an autosomal dominant disorder that has been mapped to 7p13. We have investigated two patients with GCPS and a cytogenetically visible microdeletion of the short arm of chromosome 7 with gene probes that have been assigned close to the proposed Greig locus. Deletion breakpoints were determined from high-resolution G- and R-banded chromosomes. In patient BC with a de novo deletion (7p12.3-7p14.2) we have found a loss of the genomic region containing the T-cell receptor gamma (TCRG) gene cluster, whereas the other patient IR with a deletion (7p11.2-7p13) due to a de novo translocation was apparently normal for this region. Gene dosage analysis revealed a loss of the phosphoglycerate mutase muscular form (PGAM2) gene locus in both patients. Hox 1.4 and interferon-beta 2 (IFNB2) showed a normal gene dosage. Our investigations revealed the following ordering and assignments of the studied genes: PGAM2 and GCPS in 7p12.3-13; TCRG in the distal part of 7p13-7p14.2; Hox 1.4 and IFNB2 distal to 7p14.2. Our results suggest a location of the TCRG gene more proximal than that reported previously. Furthermore, we were able to exclude the Hox 1.4 gene from involvement in the pathogenesis of GCPS. 相似文献
46.
Amr A Saad Darren M Ashcroft Kath D Watson Kimme L Hyrich Peter R Noyce Deborah PM Symmons the British Society for Rheumatology Biologics Register 《Arthritis research & therapy》2009,11(2):R52
Introduction
Anti-TNF therapies represent a breakthrough in the treatment of severe psoriatic arthritis. However, little is known about long-term drug persistence with these treatments in patients with psoriatic arthritis in routine clinical practice. The aim of this study was to assess persistence with first-course and second-course treatment with anti-TNF agents in a prospective cohort of psoriatic arthritis patients and to identify factors associated with and reasons for drug discontinuation. 相似文献47.
Abstract Many albatross populations are declining and a major cause is believed to be incidental mortality from fishing. We investigated the effect of fishing on southern Buller's albatross Thalassarche bulleri bulleri, using a new approach to seabird population modelling that allows estimation of demographic parameters from multiple data types. Three types of data were used: a 60-year set of mark–recapture observations, four censuses of the breeding population, and estimates of fishing effort and bycatch. The fisheries risk to the viability of this population over the last 60 years appears to have been small, since the adult population is estimated to have increased about five-fold over that time. There is some cause for concern in recent changes (population growth has slowed, and perhaps reversed, and adult survival rates are falling). The most common age at first breeding was 12 years, and about 80% of adults breed each year. Annual survival was estimated to be 0.91 for juveniles, and varied between this value and 1 for adults. Though this population is not in immediate danger from fishing, there is a need for continued monitoring to see whether the recent fall in survival rates persists and causes a decline in abundance. Our analysis showed that when, as is common, mark–recapture data do not provide good estimates of all demographic rates, the assessment of seabird population trends can be improved by the use of other types of data, particularly abundance. 相似文献
48.
Microbial diversity and complexity in hypersaline environments: A preliminary assessment 总被引:4,自引:0,他引:4
The microbial communities in solar salterns and a soda lake have been characterized using two techniques: BIOLOG, to estimate
the metabolic potential, and amplicon length heterogeneity analysis, to estimate the molecular diversity of these communities.
Both techniques demonstrated that the halophilic Bacteria and halophilic Archaea populations in the Eilat, Israel saltern
are dynamic communities with extensive metabolic potentials and changing community structures. Halophilic Bacteria were detected
in Mono Lake and the lower salinity ponds at the Shark Bay saltern in Western Australia, except when the crystallizer samples
were stressed by exposure to Acid Green Dye #9899. At Shark Bay, halophilic Archaea were found only in the crystallizer samples.
These data confirm both the metabolic diversity and the phylogenetic complexity of the microbial communities and assert the
need to develop more versatile media for the cultivation of the diversity of bacteria in hypersaline environments. Journal of Industrial Microbiology & Biotechnology (2002) 28, 48–55 DOI: 10.1038/sj/jim/7000175
Received 20 May 2001/ Accepted in revised form 15 June 2001 相似文献
49.
Marike van der Leeden Martijn PM Steultjens Dirkjan van Schaardenburg Joost Dekker 《Arthritis research & therapy》2010,12(1):R3
Introduction
The aim of our study was to investigate the presence of disease activity in the metatarsophalangeal (MTP) joints of the forefoot in rheumatoid arthritis (RA) patients in remission according to the Disease Activity Score based on 28 joints (DAS28) remission criterion. 相似文献50.
Christopher T. Gordon Florence Petit Peter M. Kroisel Linda Jakobsen Roseli Maria Zechi-Ceide Myriam Oufadem Christine Bole-Feysot Solenn Pruvost Cécile Masson Frédéric Tores Thierry Hieu Patrick Nitschké Pernille Lindholm Philippe Pellerin Maria Leine Guion-Almeida Nancy Mizue Kokitsu-Nakata Siulan Vendramini-Pittoli Arnold Munnich Stanislas Lyonnet Muriel Holder-Espinasse Jeanne Amiel 《American journal of human genetics》2013