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91.
Comprehensive mutational scanning of the p53 coding region by two- dimensional gene scanning 总被引:2,自引:0,他引:2
A comprehensive mutational scanning test for the p53 coding region based on
multiplex PCR and two-dimensional DNA electrophoresis was designed and
evaluated. In a 2-step multiplex PCR, the p53 coding region (exons 2-11)
was amplified as a single 8646-bp fragment by long- distance PCR in step
one. This fragment served as a template for the subsequent co-amplification
of the individual exons in two multiplex groups in step two. The multiplex
products were then separated, first on the basis of size in non-denaturant
polyacrylamide gels and then on the basis of sequence by denaturing
gradient gel electrophoresis (DGGE). Primers for optimal PCR, melting
behavior and 2-D gel distribution were designed using a recently developed
computer program. The resulting two-dimensional gene scanning (TDGS) test
was evaluated by screening, in a blinded fashion, 29 coded DNA samples from
Li- Fraumeni syndrome patients with previously identified germline
mutations. All mutations were correctly detected. This assay provides an
accurate, cost-effective and non-radioactive method for simultaneous
mutational scanning of all p53 coding exons.
相似文献
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U. TEDGÅRD 《Haemophilia》1998,4(4):365-369
Summary. Attitudes towards prenatal diagnosis, and abortion vary widely between different countries, religions, cultures and over time. Carrier testing and prenatal diagnosis (PD) of haemophilia have become an integrated part of the comprehensive care for haemophilia in Sweden as well as in many other countries. Almost all carriers are interested in carrier testing if they are aware of the possibility. With the development of PD by chorionic villus sampling in the first trimester, the method became acceptable for many carriers, and it has in Sweden actually had an effect on the incidence of haemophilia in the 1990s. The use of PD is more common among women who perceive haemophilia as a very serious disease and who have a positive attitude towards legal abortion. The main reason for carriers not to use PD was that they do not find haemophilia to be a sufficiently serious disorder to justify an abortion. Women and their spouses are under a great deal of psychological pressure in association with the PD procedure, and the psychological consequences of having to terminate a pregnancy are long-lasting. At follow-up, about 6 years after PD and abortion, these women, however, do not have more signs of psychological distress than women without PD experience. Nevertheless, they must be offered qualified assistance both before and after PD as well as adequate follow-up after an abortion to help them cope with the emotional strain they are under. 相似文献
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Kinetic evaluation of the pool sizes and proliferative response of neutrophils in bacterially challenged aging mice 总被引:2,自引:0,他引:2
Clinical observations during infection suggest that in aged patients, the kinetic or proliferative responses of neutrophils to infection may be deranged. To test this hypothesis, the neutrophil responses of 6- month-old and 30-month-old mice were compared. After intrapulmonary injection of Escherichia coli, young mice exhibited neutrophilia and diminution of the neutrophil storage pool (NSP) by a mean of 6.4 x 10(6) neutrophils/two femurs. This was accompanied by an increase in the pool of CFU-GM from a control value of 1.1 x 10(5) cells/two femurs (range 0.7 to 1.4) to 1.5 x 10(5) (1.1 to 1.9) (P less than .05) and the thymidine suicide (relative proliferative rate) of CFU-GM rose from 27% (19 to 42) to 51% (31 to 61) (P less than .05). Furthermore, the CFU-GM of infected young mice displayed enhanced differentiation to the neutrophil series. In contrast, old mice exhibited a greater mean diminution of the NSP: 12.8 x 10(6) neutrophils. Also, old mice experienced a reduction in CFU-GM from 2.3 x 10(5) (1.0 to 3.9) (controls) to 1.3 x 10(5) (1.2 to 1.5)/two femurs (P less than .05), a reduction in the proliferation of CFU-GM and reduced differentiation of CFU-GM to neutrophils. These experiments establish that the neutrophil response of infected old mice is disordered, with exaggerated depletion of the NSP and lack of stimulus-driven granulocytopoiesis as reflected by a paradoxical reduction in the number and proliferative rate of precursors. This defect may be compounded by decreased differentiation of precursors to neutrophils. 相似文献
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The Effect of a Low Fructose and Low Glycemic Index/Load (FRAGILE) Dietary Intervention on Indices of Liver Function,Cardiometabolic Risk Factors,and Body Composition in Children and Adolescents With Nonalcoholic Fatty Liver Disease (NAFLD) 下载免费PDF全文
Diana R. Mager PhD RD Ingrid Rivera Iñiguez MSc Susan Gilmour MD FRCPC MSc Jason Yap MBChB FRACP 《JPEN. Journal of parenteral and enteral nutrition》2015,39(1):73-84
Background: Nonalcoholic fatty liver disease (NAFLD) is a common liver disease in obese children. Diets high in added fructose (high fructose corn syrup; HFCS) and glycemic index (GI)/glycemic load (GL) are associated with increased risk of NAFLD. Lifestyle modification is the main treatment, but no guidelines regarding specific dietary interventions for childhood NAFLD exist. We hypothesized that reductions in dietary fructose (total, free, and HFCS)/GI/GL over 6 months would result in improvements in body composition and markers of liver dysfunction and cardiometabolic risk in childhood NAFLD. Methods: Children and adolescents with NAFLD (n = 12) and healthy controls (n = 14) 7–18 years were studied at baseline and 3 and 6 months post–dietary intervention. Plasma markers of liver dysfunction (ALT, AST, γGT), cardiometabolic risk (TG, total cholesterol, LDL‐HDL cholesterol, Apo‐B100, Apo‐B48, Apo‐CIII, insulin, homeostasis model of assessment of insulin resistance [HOMA‐IR]), inflammation (TNF‐α, IL‐6, IL‐10), anthropometric, and blood pressure (BP) were studied using validated methodologies. Results: Significant reductions in systolic BP (SBP), percentage body fat (BF), and plasma concentrations of ALT (P = .04), Apo‐B100 (P < .001), and HOMA‐IR were observed in children with NAFLD at 3 and 6 months (P < .05). Dietary reductions in total/free fructose/HFCS and GL were related to reductions in SBP (P = .01), ALT (P = .004), HOMA‐IR (P = .03), and percentage BF in children with NAFLD. Reductions in dietary GI were associated with reduced plasma Apo‐B100 (P = .02) in both groups. With the exception of Apo‐B100, no changes in laboratory variables were observed in the control group. Conclusion: Modest reductions in fructose (total/free, HFCS) and GI/GL intake result in improvements of plasma markers of liver dysfunction and cardiometabolic risk in childhood NAFLD. 相似文献
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Christiane Bergamasco RD Lilian Mika Horie RD Raquel Susana Torrinhas BD Dan L. Waitzberg MD PhD 《JPEN. Journal of parenteral and enteral nutrition》2015,39(8):941-947
Background: The daily consumption of dietary fiber is frequently below suggested recommendations. Using a double‐blind, controlled, randomized study, we assessed the efficiency and tolerance of a fiber‐enriched orange juice to supplement fiber intake in women. Materials and Methods: After 1 week of noninterventional observation, 192 healthy adult women ingested 400 mL of orange juice for 21 days, which either was not (placebo group) or was enriched with fiber (fiber group). Orange juice ingestion was registered daily and controlled for each week during the study period. Macronutrient, fiber, and energy intake were determined using a 3‐day food record, validated food chemical composition databases, and the “Pro Diet” software. Gastrointestinal symptoms were self‐evaluated daily by scoring 4 grades of symptom intensity and using a visual analog scale to grade pain severity. Results: No changes were observed for macronutrient and energy ingestion. For the placebo group (n = 97), the total fiber intake record was under the daily recommended value. In contrast, the fiber group (n = 95) displayed higher comparative values of total and soluble fiber consumption (P ≤ .001), achieving the daily recommended values of fiber intake. Both groups reported an increased frequency of slight bloating and rumbles over time (P ≤ .05). The fiber group also experienced a higher frequency of slight flatulence over time (P = .002). Conclusion: Consumption of fiber‐enriched orange juice was efficient to achieve the daily fiber intake recommendation for women, was not accompanied by intense adverse events, and may represent a suitable method to supplement fiber intake in woman. 相似文献