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31.
Baptiste Janela Amit A. Patel Mai Chan Lau Chi Ching Goh Rasha Msallam Wan Ting Kong Michael Fehlings Sandra Hubert Josephine Lum Yannick Simoni Benoit Malleret Francesca Zolezzi Jinmiao Chen Michael Poidinger Ansuman T. Satpathy Carlos Briseno Christian Wohn Bernard Malissen Florent Ginhoux 《Immunity》2019,50(4):1069-1083.e8
32.
Pulivarthi H Rao Charles P Harris Xin Yan Lu Xiao-Nan Li Samuel C Mok Ching C Lau 《Genes, chromosomes & cancer》2002,33(2):123-132
We applied multicolor spectral karyotyping (SKY) to decipher the chromosomal complexity of a panel of seven cell lines and four primary tumors derived from patients with high‐grade serous adenocarcinoma of the ovary. By this method we identified a total of 188 unbalanced translocations, nine reciprocal translocations [t(2;15)(q13;q23), t(7;17) (q32;q21), t(8;22)(p11;q11), t(8;22) (q24;q13), t(10;19) (q24;q13.2), t(11;19) (q13;p11), t(12;21)(q13;q22),t(18;20) (q?11;q?11), t(18;22)(q?11;q?13)], 6 isochromosomes [i(1q), i(7q), i(8q), i(9p), i(17q), i(21q)], and 23 deletions. By detailed mapping of rearrangement breakpoints, it was possible to identify several recurring breakpoint clusters at chromosomal bands 1p36, 2p11, 2p23, 3p21, 3q21, 4p11, 6q11, 8p11, 9q34, 10p11, 11p11, 11q13, 12p13, 12q13, 17q21, 18p11, 18q11, 20q11, and 21q22. Recurrent interstitial deletion of chromosomal bands 8p11, 11p11, and 12q13 and a recurrent unbalanced translocation—der(6)t(6;8)(q11;q11)—were also identified. In addition, a homogeneously staining region localized in one cell line to 11q13 was found using SKY to be derived from genetic material originating from chromosome 12. Subsequent comparative genomic hybridization (CGH) studies on this tumor revealed the amplification of DNA sequences derived from the short arm of chromosome 12 at the 12p11.2 region. These studies demonstrate the power of SKY, CGH, and G‐banding to resolve the full spectrum of chromosomal rearrangements in serous ovarian adenocarcinoma. © 2002 Wiley‐Liss, Inc. 相似文献
33.
Comparison of ethanol versus formalin fixation on preservation of histology and RNA in laser capture microdissected brain tissues 总被引:1,自引:0,他引:1
Su JM Perlaky L Li XN Leung HC Antalffy B Armstrong D Lau CC 《Brain pathology (Zurich, Switzerland)》2004,14(2):175-182
Although RNA can be retrieved from formalin-fixed, paraffin-embedded (FFPE) tissues, the yield is low, and the RNA is fragmented. Recent advances in gene expression profiling underscore the importance of identifying a fixative that preserves histology and mRNA. We demonstrated that, for immersion fixation of brains, 70% ethanol is superior to formalin for mRNA preservation. RNA yield from ethanol-fixed tissues was 70% of the yield from fresh frozen specimens, but only a negligible quantity was recovered from formalin-fixed tissues. RNA from ethanol-fixed brains showed integrity comparable to RNA from fresh frozen tissues, and RT-PCR using RNA from ethanol-fixed tissues was consistently successful. RNA from FFPE tissues composed of low-molecular weight fragments, and their use in RT-PCR failed repeatedly. The yield and quality of RNA from ethanol-fixed brains were unaffected after immersion at 4 degrees C for 2 weeks. In a blinded comparison to FFPE tissues, ethanol-fixed specimens were judged to show comparable histology and superior immunostaining. After laser capture microdissection (LCM), we failed to recover mRNA from FFPE tissues but retrieved mRNA from ethanol-fixed tissues for RT-PCR and cDNA microarray analysis. We conclude that 70% ethanol preserves RNA integrity and is suitable for expression profiling of brain tissues by LCM and cDNA microarray. 相似文献
34.
A selenium-containing nucleoside at the first position of the anticodon in seleno-tRNAGlu from Clostridium sticklandii. 总被引:4,自引:3,他引:1 下载免费PDF全文
W M Ching B Alzner-DeWeerd T C Stadtman 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(2):347-350
In previous studies, the single selenonucleoside component of a selenium-containing tRNAGlu isolated from Clostridium sticklandii has been shown to be 5-methyl-aminomethyl-2-selenouridine. Here, we show that this selenonucleoside is most likely located at the "wobble" position of the anticodon of the clostridial seleno-tRNAGlu. Nuclease T1 digestion of this seleno-tRNAGlu generated one major selenium-containing oligonucleotide (25 bases long). The selenium-containing residue within this oligonucleotide was located by sequence analysis of the oligonucleotide before and after removal of selenium by treatment with cyanogen bromide. The sequence of this oligonucleotide, A-A-C-C-G-C-C-C-U-U+-U-C-A+C-G-G-C-G-G-U-A-A-C-A-G, is homologous to that of the Escherichia coli tRNAGlu2 from residues 27 to 50, including the anticodon region and the variable loop, except that the E. coli tRNA has 5-methylaminomethyl-2-thiouridine instead of the selenonucleoside. 相似文献
35.
Winnie K. W. So Judy Y. W. Chan Bernard M. H. Law Kai Chow Choi Jessica Y. L. Ching Kam Leung Chan Raymond S. Y. Tang Carmen W. H. Chan Justin C. Y. Wu Stephen K. W. Tsui 《Nutrients》2021,13(2)
Rice bran exhibits chemopreventive properties that may help to prevent colorectal cancer (CRC), and a short-term rice bran dietary intervention may promote intestinal health via modification of the intestinal microbiota. We conducted a pilot, double-blind, randomised placebo-controlled trial to assess the feasibility of implementing a long-term (24-week) rice bran dietary intervention in Chinese subjects with a high risk of CRC, and to examine its effects on the composition of their intestinal microbiota. Forty subjects were randomised into the intervention group (n = 19) or the control group (n = 20). The intervention participants consumed 30 g of rice bran over 24-h intervals for 24 weeks, whilst the control participants consumed 30 g of rice powder on the same schedule. High rates of retention (97.5%) and compliance (≥91.3%) were observed. No adverse effects were reported. The intervention significantly enhanced the intestinal abundance of Firmicutes and Lactobacillus, and tended to increase the Firmicutes/Bacteroidetes ratio and the intestinal abundance of Prevotella_9 and the health-promoting Lactobacillales and Bifidobacteria, but had no effect on bacterial diversity. Overall, a 24-week rice bran dietary intervention was feasible, and may increase intestinal health by inducing health-promoting modification of the intestinal microbiota. Further larger-scale studies involving a longer intervention duration and multiple follow-up outcome assessments are recommended. 相似文献
36.
Gabriela E. Leghi Merryn J. Netting Ching T. Lai Ardra Narayanan Michael Dymock Alethea Rea Mary E. Wlodek Donna T. Geddes Beverly S. Muhlhausler 《Nutrients》2021,13(6)
Maternal diet has the potential to affect human milk (HM) composition, but very few studies have directly assessed the effect of maternal diets on HM composition. The primary aim of this study was to assess the effect of improving dietary quality in lactating women over 2 weeks on the concentrations of macronutrients and metabolic hormones in HM. The secondary aims were to assess the impact of the dietary intervention on 24 h milk production, maternal body composition and infant growth. Fifteen women completed a 1-week baseline period followed by a 2-week dietary intervention phase targeted towards reducing fat and sugar intake. Maternal anthropometric and body composition and infant growth measurements were performed weekly. Total 24 h milk production was measured before and after the dietary intervention, and HM samples were collected daily. Maternal intakes of energy (−33%), carbohydrate (−22%), sugar (−29%), fat (−54%) and saturated fat (−63%) were significantly reduced during the dietary intervention. HM insulin, leptin and adiponectin concentrations were 10–25% lower at the end of the dietary intervention, but HM concentrations of macronutrients were unaffected. Maternal body weight (−1.8%) and fat mass (−6.3%) were significantly reduced at the end of the dietary intervention, but there were no effects on 24 h milk production or infant growth. These results suggest that reducing maternal energy, carbohydrate, fat and sugar intake over a 2-week period is associated with significant reductions in HM insulin, leptin and adiponectin concentrations. These changes may be secondary to decreases in maternal weight and fat mass. The limited studies to date that have investigated the association between metabolic hormone concentrations in HM and infant growth raise the possibility that the changes in HM composition observed in the current study could impact infant growth and adiposity, but further studies are required to confirm this hypothesis. 相似文献
37.
Ching Shan Wan Jade Mitchell Andrea B. Maier 《Journal of the American Medical Directors Association》2021,22(6):1331.e1-1331.e9
ObjectivesTo evaluate the effect of Hospital Admission Risk Program (HARP) on unplanned hospitalization, bed days, and mortality of enrolled individuals and to evaluate the cost-effectiveness of HARP.DesignA retrospective longitudinal analysis of hospital administrative data.InterventionIndividuals at risk of hospitalization were provided with multidisciplinary, community-based care support managed by care coordinators including integrated care planning, education, monitoring, service linkages, and general practitioner liaison over 6-9 months.Setting and ParticipantsIndividuals who were enrolled into 1 of 8 HARP chronic disease management programs between July 1, 2017, and June 30, 2018, at the Royal Melbourne Hospital, Australia.MethodsHospital admissions between 18 months before and 18 months after HARP enrollment were analyzed. Total hospital costs were compared between 18 months before and 12 months after HARP enrollment.ResultsA total of 1553 individuals with a median age of 71 years (interquartile range 60-81), 63.4% males, were admitted to HARP. Both unplanned hospitalizations and bed days were reduced during the HARP intervention compared to within 3 months before enrollment in each of the HARP management programs. After the HARP intervention, cardiac coach, cardiac heart failure, chronic respiratory, diabetes comanagement, and medication management programs had higher hospitalizations and bed days than individuals’ baseline of at least 3 months before HARP enrollment. Individuals in cardiac heart failure and chronic respiratory management programs had a higher mortality rate than other HARP chronic disease management programs. Individuals in cardiac coach, diabetes comanagement, and medication management programs had lower hospital costs during the HARP intervention compared to within 3 months before HARP enrollment.Conclusions and ImplicationsHARP reduced unplanned hospitalization and bed days but did not return individuals’ hospital use to baseline before the intervention. The variations in mortality between HARP chronic disease management programs implies that condition-specific goals between programs is preferable. 相似文献
38.
Johnson Bryan A. Lindgren Bruce R. Blaes Anne H. Parsons Helen M. LaRocca Christopher J. Farah Ronda Hui Jane Yuet Ching 《Annals of surgical oncology》2021,28(10):5668-5676
Annals of Surgical Oncology - Telemedicine was adopted to minimize exposure risks for patients and staff during the coronavirus disease 2019 pandemic. This study measured patient satisfaction and... 相似文献
39.
Growth of bone marrow cells on porous ceramics in vitro 总被引:8,自引:0,他引:8
Following the transplantation of bone marrow cells to extra-osseous sites, bone formation occurs in those sites. This osteogenic potential of bone marrow cells might be utilized for filling defects in bone if they could be transported on porous ceramic materials. Before such an approach becomes feasible, it is important to know what happens to the cells in the presence of the ceramics that might be used. In order to investigate the interaction between bone marrow cells and ceramics, in vitro, a system for culturing bone marrow cells on ceramic materials has been developed. Bone marrow cells adhered well to the surface of calcium hydroxyapatite and tricalcium phosphate ceramics, and this was followed by the formation of fibrous tissue on and within the ceramics. These ceramics were compatible with bone marrow cells even in culture conditions in which there was a large surface area of ceramic interfacing with cells. The results support the proposal that calcium hydroxyapatite and tricalcium phosphate are appropriate as bone replacement materials. In contrast, calcium aluminate had an adverse effect on bone marrow cells when there was a high proportion of ceramic to culture medium. However, this effect was not present if the proportion of ceramic to culture medium was low. Therefore, a large amount of biodegradable porous calcium aluminate ceramic should not be used as an alternative to autogeneous bone grafting. 相似文献
40.
Tim Borges Howard P. Glauert Li -Chuan Chen Ching K. Chow Larry W. Robertson 《Archives of toxicology》1990,64(1):26-30
The possible interrelationships between the effects of dietary selenium and perfluorodecanoic acid (PFDA) on growth and lipid metabolism were studied in the male Sprague Dawley rat. Rats were divided into groups and placed on diets containing three levels of selenium (0.04, 0.2, and 1.0 ppm as sodium selenite). Two weeks later, half the rats in each group received a single 35 mg/kg IP injection of PFDA in corn oil, while their pair-fed companion received only vehicle. Rats injected with PFDA stopped gaining weight, and weighed less than pair-fed controls, despite equal food intakes. Two weeks following PFDA administration the rats were killed and plasma cholesterol and triglycerides, and liver peroxisomal enzyme activities were quantified. In contrast to other peroxisome proliferators, PFDA increased plasma triglycerides while decreasing plasma cholesterol. The rate of peroxisomal fatty acid -oxidation was decreased, even though the activity of fatty acyl-CoA oxidase, the first enzyme in the peroxisomal fatty acid -oxidation pathway, was increased. Dietary selenium, other than increasing the liver to body weight ratio, did not alter growth or lipid metabolism. This study demonstrates, for the first time, the existence of a non-hypotriglyceridemic peroxisome proliferator-PFDA. 相似文献