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MATERIALS AND METHODS: We describe the isolation of RNA from 8 nm sections of formalin-fixed paraffin-embedded oral mucosal tissue. RNA was reverse transcribed and three candidate genes amplified by polymerase chain reaction (PCR). The ribosomal protein S14 gene is a housekeeping gene which has been used as an internal standard in several quantitative PCR protocols. The thymidine kinase (TK) gene is expressed at low levels in most tissues and, with a well-documented genomic organisation, is a useful tool for discrimination between genomic DNA and cDNA. The RIa gene is reported to be overexpressed in many cancer cell lines, in malignant tissue and in vitro transformed cellS. RESULTS: The S14 gene, the TK gene and the RIα gene of the cAMP-dependent protein kinase (PKA) were amplified successfully from formalin-fixed paraffin-embedded tissue sections. The TK primer pair is a useful additional tool in the unambiguous identification of RNA-derived species.
CONCLUSION: RNA suitable for reverse transcribed (RT)-PCR was extracted from archival oral mucosal tissue. This should permit rapid sequence analysis of transcribed tumor suppressor genes and oncogenes in this material. Furthermore, the RT-PCR approach described may allow quantification of gene expression in oral mucosal archival material processed in a standard fashion. 相似文献
MATERIALS AND METHODS: Two hundred and fifty-two non-inbred mate adult Syrian golden hamsters were randomly divided into six groups, each containing forty-two animalS. A treatment regimen over a 14-week experimental period was employed with six animals per group being killed at seven different periods (every 2 weeks). The right buccal pouch of each animal was painted three times a week with various combinations of 7, 12-dimethylbenz[a]anthracene (DMBA), Taiwan betel quid extract, dimethyl sulfoxide (DMSO) and mineral oil.
RESULT: Both the number and size of tumors in animals concurrently treated with DMBA and betel quid were significantly higher than those in animals treated with DMBA alone in each killing period of 8, 10, 12 and 14 weekS. No visible tumors but hyperkeratosis and acanthosis were observed in pouches treated with betel quid alone for all killing periods.
CONCLUSION: Our results indicate Taiwan betel quid may be a co-carcinogen in human oral carcinogenesis, if extrapolation can be made from the current animal study. 相似文献
Methods. Four commonly available diluting drinks were assessed for both pH and titratable acidity at a variety of dilutions, reflecting the range of concentrations over which such drinks may be consumed. Predetermined dilutions of citric acid and hydrochloric acid, with similar pH values to those of the drinks, were used as positive control acidic solutions. The pH measurements throughout the study were made using a pH electrode connected to an Orion EA940 IonAnalyser.
Results. All four drinks demonstrated a high degree of resistance to a rise in pH, indicating high intrinsic buffering capacity. The measured pH changed very little with increasing dilution ratio when compared to the citric and hydrochloric acid controls, even when considered extremely dilute. In contrast, the titratable acidity of each of the drinks reduced proportionally with increasing dilution, thereby reducing considerably its erosive potential.
Conclusions. While dilution had very little effect on the measured pH values, the titratable acidity reduced as the drink became more dilute. Since there appears to be a direct relationship between dilution and titratable acidity, the erosive potential of diluting juices may be reduced substantially by the addition of water. It remains unlikely, however, that the drinks would ever be consumed at a ‘safe’ level of dilution due to diminished taste and colour. 相似文献
qSOFA has been proposed as a prognostic tool in patients with sepsis. This study set out to assess the sensitivity of several scores, namely: the pre-ICU qSOFA, the qSOFA with lactate (qSOFA L), SIRS score, qSOFA + SIRS score (qSIRS) and qSIRS with lactate (qSIRS L) in predicting in-hospital mortality in patients with surgical sepsis as well as the sensitivity of these scores in predicting high-grade sepsis. The secondary aim was to determine which of these scores is best suited to predict high-grade surgical sepsis.
MethodsThis was a retrospective cohort study that was conducted between December 2012 and August 2017 in a public metropolitan surgical service. Data from patients aged > 13 years, who were admitted to the hospital and who had an emergency surgical procedure for source control were retrieved from a prospectively maintained hybrid electronic database. The qSOFA, qSOFA plus lactate (qSOFA L), SIRS and qSOFA + SIRS (qSIRS), as well as the qSIRS plus lactate (qSIRS L), were calculated for each patient. A lactate level that was greater than 2mmol/L was deemed to be a positive finding. Any score ≥2 was deemed to be a positive score. The outcome measure was in-hospital mortality. The prognostic value of qSOFA, qSOFA L, SIRS, qSIRS and qSIRS L was studied. Receiver operating characteristic analyses were performed to determine the area under the curve (AUC), sensitivity, specificity and positive and negative likelihood ratios for positive qSOFA, qSOFA L, SIRS, qSIRS, and qSIRS L. Contingency tables were used to calculate the sensitivity, specificity, PPV and NPV for predicting severe or high-grade surgical sepsis.
ResultsThere were a total number of 1884 patients in the sample group of whom 855 were female (45.4%). The median patient age was 36 years (IQR 23–56). A total of 1489 patients (79%) were deemed to have high-grade sepsis based on an advanced EGS AAST grading, whilst 395 patients (21%) had low-grade sepsis. A total of 71 patients died (3.8%). Of these patients who died, 67 (94.4%) had high-grade sepsis and 4 (5.6%) had low-grade sepsis. The mortality rate in the high-grade sepsis group was 4.5%, whilst the mortality rate in the low-grade sepsis group was 1%. The scores with the greatest accuracy in predicting mortality were qSIRS (AUROC 0.731, 95% CI 0.68–0.78), followed by SIRS (AUROC 0.70, 95% CI 0.65–0.75). The qSOFA and qSOFA L were the least accurate in predicting mortality (AUROC 0.684, 95% CI 0.63–0.74 for both). The addition of lactate had no significant effect on the accuracy of the five scores in predicting mortality. Patients with a qSOFA ≥ 2 have an increased risk of dying (OR 5.8), as do patients with a SIRS score ≥2 (OR 2.7). qSIRS L had the highest sensitivity (69%) in predicting the presence of high-grade surgical sepsis, followed by qSIRS (65.5% sensitivity). qSOFA showed a very low sensitivity of only 4.5% and a high specificity of 99.2%. The addition of lactate to the score marginally improved the sensitivity. Lactate of 2mmol/L or more was also an independent predictor of high-grade sepsis.
ConclusionThe qSIRS score is most accurate in predicting mortality in surgical sepsis. The qSOFA score is inferior to both the SIRS and the qSIRS scores in predicting mortality. The qSIRS score with the addition of lactate to the qSIRS score made it the most sensitive score in predicting high-grade surgical sepsis.
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