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61.
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
62.
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
63.
Kenneth Siu-Sing Leung Timothy Ting-Leung Ng Alan Ka-Lun Wu Miranda Chong-Yee Yau Hiu-Yin Lao Ming-Pan Choi Kingsley King-Gee Tam Lam-Kwong Lee Barry Kin-Chung Wong Alex Yat Man Ho Kam-Tong Yip Kwok-Cheung Lung Raymond Wai-To Liu Eugene Yuk-Keung Tso Wai-Shing Leung Man-Chun Chan Yuk-Yung Ng Kit-Man Sin Kitty Sau-Chun Fung Sandy Ka-Yee Chau Wing-Kin To Tak-Lun Que David Ho-Keung Shum Shea Ping Yip Wing Cheong Yam Gilman Kit-Hang Siu 《Emerging infectious diseases》2021,27(1):196
Initial cases of coronavirus disease in Hong Kong were imported from mainland China. A dramatic increase in case numbers was seen in February 2020. Most case-patients had no recent travel history, suggesting the presence of transmission chains in the local community. We collected demographic, clinical, and epidemiologic data from 50 patients, who accounted for 53.8% of total reported case-patients as of February 28, 2020. We performed whole-genome sequencing to determine phylogenetic relationship and transmission dynamics of severe acute respiratory syndrome coronavirus 2 infections. By using phylogenetic analysis, we attributed the community outbreak to 2 lineages; 1 harbored a common mutation, Orf3a-G251V, and accounted for 88.0% of the cases in our study. The estimated time to the most recent common ancestor of local coronavirus disease outbreak was December 24, 2019, with an evolutionary rate of 3.04 × 10−3 substitutions/site/year. The reproduction number was 1.84, indicating ongoing community spread. 相似文献
64.
Julie Bennett Jane Zhang William Leung Susan Jack Jane Oliver Rachel Webb Nigel Wilson Dianne Sika-Paotonu Matire Harwood Michael G. Baker 《Emerging infectious diseases》2021,27(1):36
We describe trends in acute rheumatic fever (ARF), rheumatic heart disease (RHD), and RHD deaths among population groups in New Zealand. We analyzed initial primary ARF and RHD hospitalizations during 2000–2018 and RHD mortality rates during 2000–2016. We found elevated rates of initial ARF hospitalizations for persons of Māori (adjusted rate ratio [aRR] 11.8, 95% CI 10.0–14.0) and Pacific Islander (aRR 23.6, 95% CI 19.9–27.9) ethnicity compared with persons of European/other ethnicity. We also noted higher rates of initial RHD hospitalization for Māori (aRR 3.2, 95% CI 2.9–3.5) and Pacific Islander (aRR 4.6, 95% CI 4.2–5.1) groups and RHD deaths among these groups (Māori aRR 12.3, 95% CI 10.3–14.6, and Pacific Islanders aRR 11.2, 95% CI 9.1–13.8). Rates also were higher in socioeconomically disadvantaged neighborhoods. To curb high rates of ARF and RHD, New Zealand must address increasing social and ethnic inequalities. 相似文献
65.
Leung H Hughes C Kloppel G Williamson R Lemoine N 《International journal of oncology》1994,4(6):1219-1223
Growth factors may play a role in autocrine or paracrine growth control of tumour cells. We have now examined the expression pattern in vivo by in situ hybridization (ISH) on a series of 13 ductal adenocarcinomas of the pancreas using the non-radioactive digoxigenin system to generate specific antisense orientated riboprobes for FGF-1 and FGF-2, and the four FGFRs (FGFR-1, -2, -3 and -4). We confirmed the expression of both FGF/FGFR by tumour cells, with the potential of a potential autocrine loops in 46% of the cases studied. FGF-2 and FGFR-3 were the most commonly expressed ligand and receptor (46% and 76% respectively). Endothelial cells lining vessels within an around invasive tumours were frequently positive for expression of FGFR-1 and/or FGFR-3. In the normal pancreas remote from the tumour, the acinar cells were found to have a heterogeneous expression pattern for FGFRs while duct cells, islet cells and stromal components including nerves and vascular endothelium were negative. The data suggest a role for FGFs and their high affinity receptors in the control of growth of human pancreatic adenocarcinoma and its supporting stroma. 相似文献
66.
Rubin GD Shiau MC Schmidt AJ Fleischmann D Logan L Leung AN Jeffrey RB Napel S 《Journal of computer assisted tomography》1999,23(Z1):S83-S90
Since its clinical introduction in 1991, volumetric computed tomography scanning using spiral or helical scanners has resulted in a revolution for diagnostic imaging. In addition to new applications for computed tomography, such as computed tomographic angiography and the assessment of patients with renal colic, many routine applications such as the detection of lung and liver lesions have substantially improved. Helical computed tomographic technology has improved over the past eight years with faster gantry rotation, more powerful X-ray tubes, and improved interpolation algorithms, but the greatest advance has been the recent introduction of multi detector-row computed tomography scanners. These scanners provide similar scan quality at a speed gain of 3-6 times greater than single detector-row computed tomography scanners. This has a profound impact on the performance of computed tomography angiography, resulting in greater anatomic coverage, lower iodinated contrast doses, and higher spatial resolution scans than single detector-row systems. 相似文献
67.
Pulmonary tuberculosis: the essentials 总被引:38,自引:0,他引:38
Leung AN 《Radiology》1999,210(2):307-322
68.
PURPOSE: To study the morphologic characteristics of late radiation injury to the temporal lobes of the brain on magnetic resonance (MR) images. MATERIALS AND METHODS: This was a prospective study involving 34 patients (age range, 37-72 years) with known radiation injury to the temporal lobes from radiation therapy administered 2-10 years previously for nasopharyngeal carcinoma MR imaging was performed with T2-weighted gradient- and spin-echo, gradient-recalled echo, T1-weighted spin-echo, fluid-attenuated inversion-recovery, and T1-weighted postcontrast spin-echo sequences. RESULTS: Radiation injury was present in 57 of the 68 temporal lobes. The white matter lesions in radiation-induced injury were predominantly hyperintense on T2-weighted images, but in 37 (65%) of the 57 lobes, foci with heterogeneous signal intensity consistent with necrosis were detected. In the 57 involved lobes, gray matter lesions were detected in 50 (88%); blood-brain barrier disruption based on parenchymal contrast enhancement, in 51 (89%); and hemosiderin deposits, in 30 (53%). There was a significant correlation between white matter necrosis, gray matter lesions, and blood-brain barrier disruption, all of which were located mainly in the inferior temporal lobes that received the highest radiation dose. CONCLUSION: The lesion components of radiation-induced injury to the temporal lobes at MR imaging were more varied than have been previously described. In addition to the classic white matter lesions, gray matter lesions, blood-brain barrier disruption, and hemosiderin deposition also were frequently seen. 相似文献
69.
Abstract: To determine the effectiveness of screening mammography in a community medical setting, data from a population-based, retrospective study was analyzed. Medical records of 827 patients with newly diagnosed breast cancer in California between October 1994 and March 1996 were reviewed. The primary care physician's record was abstracted for clinical history, including recommendation of screening mammography. The facility records where final diagnosis was made were abstracted for stage and treatment data. Among the patients who did not have previous screening mammography, 65.7% were diagnosed with "advanced" breast cancer (stages II, III, IV), while only 39.9% who had previous screening mammography were diagnosed with advanced breast cancer (p < 0.001). This study has reaffirmed that screening mammography of adult females generates downstaging at the time of diagnosis of breast cancer. Despite possession of a health insurance program and receiving educational materials, only 65% of patients over 50 years of age had screening mammography. As opposed to the once-a-year mailing of general reminders to all women 40 years old and older, developing a longitudinal electronic medical record in the managed care setting will support a more coordinated and individualized intervention based on age, date of last mammogram, and relative risk, among other factors. Continuing education efforts must also be directed to referring physicians, who may not yet recognize the value of screening mammography. 相似文献
70.
Core beliefs in anorexic and bulimic women 总被引:1,自引:0,他引:1
There is research evidence to suggest the presence of dysfunctional cognitions in anorexia nervosa and bulimia nervosa that are not related to food, weight, or shape. These maladaptive cognitions have not been addressed by the conventional cognitive behavioral models of etiology or therapy. This study aimed to assess the impact of unhealthy core beliefs on eating disorders and their symptoms. Twenty restricting anorexics, 10 bulimic anorexics, 27 bulimics, and 23 normal controls completed Young's Schema Questionnaire. Eating behaviors and attitudes were also measured. The results indicate that both anorexic and bulimic women had significantly higher levels of unhealthy core beliefs than comparison women, but the clinical groups only differed on one individual core belief (entitlement). However, there were different patterns of association between core beliefs and eating psychopathology in anorexic and bulimic women. It is suggested that future clinical practice should incorporate core beliefs as a potential element in the assessment and treatment of eating disorders. 相似文献