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531.
Two colorectal cancer (CRC) susceptibility loci have been found to be significantly associated with an increased risk of CRC in Dutch Lynch syndrome (LS) patients. Recently, in a combined study of Australian and Polish LS patients, only MLH1 mutation carriers were found to be at increased risk of disease. A combined analysis of the three data‐sets was performed to better define this association. This cohort‐study includes three sample populations combined totaling 1,352 individuals from 424 families with a molecular diagnosis of LS. Seven SNPs, from six different CRC susceptibility loci, were genotyped by both research groups and the data analyzed collectively. We identified associations at two of the six CRC susceptibility loci in MLH1 mutation carriers from the combined LS cohort: 11q23.1 (rs3802842, HR = 2.68, p ≤ 0.0001) increasing risk of CRC, and rs3802842 in a pair‐wise combination with 8q23.3 (rs16892766) affecting age of diagnosis of CRC (log‐rank test; p ≤ 0.0001). A significant difference in the age of diagnosis of CRC of 28 years was observed in individuals carrying three risk alleles compared to those with 0 risk alleles for the pair‐wise SNP combination. A trend (due to significance threshold of p ≤ 0.0010) was observed in MLH1 mutation carriers towards an increased risk of CRC for the pair‐wise combination (p = 0.002). This study confirms the role of modifier loci in LS. We consider that LS patients with MLH1 mutations would greatly benefit from additional genotyping of SNPs rs3802842 and rs16892766 for personalized risk assessment and a tailored surveillance program.  相似文献   
532.
In some cases of chronic urticaria it is suspected that food additives such as tartrazine and sodium benzoate or salicylates may play a role in the pathogenesis of the condition. Since, at times, chronic urticaria may appear histologically similar to a mild cell-mediated immune response, the release of the T cell-derived lymphokine leucocyte inhibitory factor (LIF), in response to incubation with these additives and with acetylsalicylic acid (ASA), was measured in vitro using cells from normal controls, from patients with chronic urticaria with or without clinically associated additive sensitivity and from patients with asthma with or without associated ASA sensitivity. It was found that significant production of LIF occurred in response to tartrazine and sodium benzoate in those individuals with chronic additive induced urticaria. In addition, tartrazine caused LIF release from mononuclear cells of ASA-sensitive asthmatics. These results may indicate a possible role for additive-induced cell-mediated immune responses in the pathogenesis of some cases of chronic urticaria and suggest a potential diagnostic test for this condition.  相似文献   
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Trisomy 3 in low-grade B-cell lymphomas of mucosa-associated lymphoid tissue   总被引:13,自引:3,他引:13  
Wotherspoon  AC; Finn  TM; Isaacson  PG 《Blood》1995,85(8):2000-2004
Characteristic chromosomal aberrations have been associated with subtypes of non-Hodgkin's lymphoma with distinct clinicopathologic features. Low-grade B-cell lymphomas of mucosa-associated lymphoid tissue (MALT) form such a group and might be expected to be characterized by a specific cytogenetic abnormality. Metaphase analyses of MALT lymphoma are rare due to problems with fresh tissue collection and poor in vitro proliferation. However, the small number of published series suggests that chromosome trisomies, particularly trisomy 3, might be characteristic of these tumors. The application of interphase cytogenetic techniques to routinely processed material allows the examination of a large series of archival cases and is particularly useful for the demonstration of chromosome trisomies. We have used this technique to analyze 70 cases of low-grade MALT lymphoma from various sites and found trisomy 3 in 60%. This finding compares with 16% in low- grade nodal B-cell lymphoma and 27% in primary splenic lymphoma of marginal zone type (splenic lymphoma with villous lymphocytes). These results provide further evidence that low-grade MALT lymphomas from all sites form a single pathologic entity distinct from nodal B-cell lymphomas. Although MALT lymphoma and primary splenic lymphoma may arise from marginal zone B cells, they are genetically distinct.  相似文献   
535.
ObjectiveTo document movement patterns, home range, nesting behaviour and social organization of 5 individuals (3 males and 2 females) of a common species of tree-shrew, Tupaia glis (T. glis) surrounding houses of otoacariasis cases.MethodsEach shrew was fitted with a transmitter chip radio-collar which operates between the frequencies of 154.13 MHz to 154.21 MHz. Each transmitter was then tracked with a Portable Telemetry Receiver (Sirtrack, New Zealand) fitted with a 3-element Yagi antenna. Collared shrews were located using standard methods of ground-based triangulation. Each location was taken from at least 2 directional fixes and a minimum of 3 compass bearings. Fixes were taken hourly for each collared individual from the time of emergence from nest (beginning of activity) till time of entry into the nest (end of activity) every day for 5 to 7 continuous days. Three series of radio telemetry observations were carried out. The bearings, time and positions of an observer were recorded and later plotted on a graph paper in order to derive coordinates of the collared animal. [These coordinates then analyzed using Ecological Software Solutions (Biotas Version 1.03)].ResultsNests were found in a jack fruit tree, long bushes, and 2 houses. Daily telemetry detections demonstrated 2 individuals of different sex having nests (or a nest) in the same house. All shrews emerged from and returned to their nests between 0601 to 0659 hours and 1901 to 1959 hours, respectively. Both the time of exit from and entry into nest were the same between sexes (P>0.05). Their average total active period was 4.90 to 7.00 hours with a total daily travel distant of 270 m to 382 m. A male and a female shrew can move as far as 3 285 m and 4 591 m, respectively. Active movements of T. glis were during daytime. They regularly entered some houses in the area during day and night except for one individual which visited during daytime only. The sizes of home range and core area for the shrews were 2.00–3.40 ha and 0.05–0.42 ha, respectively. Generally, the mean home range size of females was 20.8% larger than that of males. Females covered a 15.4% slightly higher daily movement range compared to males.ConclusionsThis is the first radio telemetry study in Malaysia to monitor movements and home range of shrews carrying ticks on their body. It demonstrates that shrews are potential carriers of ticks from wild into the houses and their compounds based on their total active periods spent moving around from fruit orchards, secondary forest, plantations and other vegetations to trees in compound of 4 to 7 houses and vice versa. There are also evidences showing shrews have close contact with humans.  相似文献   
536.

Background and purpose:

Glucocorticoids are highly effective in the therapy of inflammatory diseases. Their value, however, is limited by side effects. The discovery of the molecular mechanisms of the glucocorticoid receptor and the recognition that activation and repression of gene expression could be addressed separately opened the possibility of achieving improved safety profiles by the identification of ligands that predominantly induce repression. Here we report on ZK 245186, a novel, non-steroidal, low-molecular-weight, glucocorticoid receptor-selective agonist for the topical treatment of inflammatory dermatoses.

Experimental approach:

Pharmacological properties of ZK 245186 and reference compounds were studied in terms of their potential anti-inflammatory and side effects in functional bioassays in vitro and in rodent models in vivo.

Key results:

Anti-inflammatory activity of ZK 245186 was demonstrated in in vitro assays for inhibition of cytokine secretion and T cell proliferation. In vivo, using irritant contact dermatitis and T cell-mediated contact allergy models in mice and rats, ZK 245186 showed anti-inflammatory efficacy after topical application similar to the classical glucocorticoids, mometasone furoate and methylprednisolone aceponate. ZK 245186, however, exhibits a better safety profile with regard to growth inhibition and induction of skin atrophy after long-term topical application, thymocyte apoptosis, hyperglycaemia and hepatic tyrosine aminotransferase activity.

Conclusions and implications:

ZK 245186 is a potent anti-inflammatory compound with a lower potential for side effects, compared with classical glucocorticoids. It represents a promising drug candidate and is currently in clinical trials.This article is part of a themed issue on Mediators and Receptors in the Resolution of Inflammation. To view this issue visit http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009  相似文献   
537.
IMMUNOELECTRONMICROSCOPICLOCALIZATIONOFGROWTHFACTORSANDOTHERMARKERSINHUMANLONG-TERMBONEMARROWCULTURES¥LiuJiewen;(刘杰文),WynterE...  相似文献   
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