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OBJECTIVE: To assess the feasibility of using archival oral mucosal tissue to examine gene expression at the ribonucleic acid (RNA) level.
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   
5.
AIMS: To test the hypothesis that local injection of the N-methyl-D-aspartate (NMDA) receptor antagonist ketamine would significantly attenuate glutamate-evoked masseter mechanical sensitization and muscle pain in healthy young women either taking oral contraceptives (W+OC) or not taking oral contraceptives (W-OC). METHODS: Experimental pain was evoked in 47 healthy female subjects (W+OC, n=25; W-OC, n=22) by 2 injections of glutamate (0.2 mL, 1 mol/L) into the masseter muscle. A first injection of glutamate alone was followed by a second injection, 35 minutes later, of glutamate combined with ketamine (0, 1, or 10 mmol/L). Evoked pain intensity was scored on a 10-cm electronic visual analog scale (VAS). Distribution of perceived pain was drawn on a lateral view of the face (pain drawing). Masseter muscle pressure pain thresholds (PPT) and pressure-pain tolerances (PPTOL) were determined bilaterally before and at regular time intervals after injections. Analyses of variance (ANOVA) were used to test the data. RESULTS: There were no main effects of ketamine on any of the VAS pain parameters or on the pain drawing (ANOVAs: P > .055). Furthermore, there were no differences in PPT, PPTOL, VAS peak pain, duration, overall VAS pain, or pain drawing when W-OC were compared with W+OC (ANOVAs: P > .087). Repeated injection of glutamate alone significantly decreased PPT and PPTOL (ANOVAs: P < .001); however, this effect was not significantly attenuated by ketamine. CONCLUSIONS: Peripherally administered ketamine had no effect on glutamate-evoked masseter muscle pain and sensitization in healthy young women, which contrasts with recent observations in healthy young men. Further studies will be needed to reveal the mechanisms that underlie this apparent sex-related difference in ketamine-mediated analgesia.  相似文献   
6.
Background : The treatment of deep dental decay has traditionally involved removal of all the soft demineralized dentine before a filling is placed. However, this has been challenged in three groups of studies which involve sealing soft caries into the tooth. The three main groups either remove no caries and seal the decay into the tooth, remove minimal (ultraconservative) caries at the entrance to a cavity and seal the remaining caries in, or remove caries in stages over two visits some months apart to allow the pulp time to lay down reparative dentine (the stepwise excavation technique). Objectives : To test the null hypothesis of no difference in the incidence of damage or disease of the nerve of the tooth (pulp), progression of decay and longevity of restorations irrespective of whether the removal of decay had been minimal (ultraconservative) or complete. Search strategy : The Cochrane Oral Health Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PubMed and EMBASE databases were searched. The reference lists in relevant papers were checked. Selection criteria : Randomized controlled trials and controlled clinical trials comparing minimal (ultraconservative) caries removal with complete caries removal in unrestored permanent and deciduous teeth. Data collection and analysis : Outcome measures recorded were exposure of the nerve of the tooth (pulp) during caries removal, patient experience of symptoms of pulpal inflammation or necrosis, progression of caries under the filling, time until the filling was lost or replaced. Due to the heterogeneity of the included studies the overall estimate of effect was calculated using a random‐effects model. Main results : Four studies met the inclusion criteria; two stepwise excavation studies and two ultraconservative caries removal studies. Partial caries removal in symptomless, primary or permanent teeth reduces the risk of pulp exposure. We found no detriment to the patient in terms of pulpal symptoms in this procedure and no reported premature loss or deterioration of the restoration. Authors' conclusions : The results of this systematic review reject the null hypothesis of no difference in the incidence of damage or disease of the nerve of the tooth (pulp) irrespective of whether the removal of decay had been minimal (ultraconservative) or complete and accepts the null hypothesis of no difference in the progression of decay and longevity of restorations. However, the number of included studies is small and differ considerably. Partial caries removal is therefore preferable to complete caries removal in the deep lesion, in order to reduce the risk of carious exposure. However, there is insufficient evidence to know whether it is necessary to re‐enter and excavate further but studies that have not re‐entered do not report adverse consequences. Plain language summary : A systematic review of the literature revealed four studies comparing complete and minimal (ultraconservative) caries removal. It was found that partial caries removal in symptomless, primary or permanent teeth reduces the risk of pulp exposure. We found no detriment to the patient in terms of pulpal symptoms in this procedure. Therefore, partial caries removal is preferable to complete caries removal in the deep lesion, in order to reduce the risk of carious exposure. However, there is insufficient evidence to know whether it is necessary to re‐enter and excavate further but studies that have not re‐entered do not report adverse consequences.  相似文献   
7.
LM Lin  YK Chen  DR Lai  YL Huang  HR Chen 《Oral diseases》1997,3(4):232-235
OBJECTIVE: To investigate the cancer-promoting effect of Taiwan betel quid in hamster buccal pouch carcinogenesis.
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   
8.
Objectives. To investigate, in vitro, the potential dental effects of diluting juices by measuring their acidity levels and to examine the effect dilution has on the potential erosive properties of the drinks.

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   

9.
Green  S. L.  Smith  M. T. D.  Cairns  C.  Clarke  D. L.  Bruce  J.  Bekker  W.  Kong  V.  Laing  G. L. 《World journal of surgery》2020,44(1):21-29
Background

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.

Methods

This 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.

Results

There 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.

Conclusion

The 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.

  相似文献   
10.
Felty's syndrome (FS) (rheumatoid arthritis with neutropenia and splenomegaly) has a poor prognosis, largely because of the high risk of severe infection. Granulocyte colony-stimulating factor (G-CSF) is an emerging treatment for chronic neutropenia. We prospectively monitored its use in eight patients with recurrent infections or who required joint surgery. Significant side-effects were documented in five, including nausea, malaise, generalized joint pains, and in one patient, a vasculitic skin rash. In two patients treatment had to be stopped, and in these cases G-CSF had been started at full vial dosage (300 micrograms/ml filgrastim or 263 micrograms/ml lenograstim) alternate days or daily. G-CSF treatment was continued in three patients by restarting at reduced dose, and changing the proprietary formulation. G- CSF raised the neutrophil count, reduced severe infection, and allowed surgery to be performed. A combined clinical and laboratory index suggested that long-term treatment (up to 3.5 years) did not exacerbate the arthritis. Once on established treatment, it may be possible to use smaller weekly doses of G-CSF to maintain the same clinical benefit. One of the three patients whose FS was associated with a large granular T-cell lymphocytosis showed a reduction in this subset of lymphocytes during G-CSF treatment.   相似文献   
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