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921.
M. D. Reboiras‐López, M. Pérez‐Sayáns, J. M. Somoza‐Martín, P. Gayoso‐Diz, F. Barros‐Angueira, J. M. Gándara‐Rey and A. García‐García Comparison of the Cytobrush®, dermatological curette and oral CDx® brush test as methods for obtaining samples of RNA for molecular analysis of oral cytology Objective: Interest in oral exfoliative cytology has increased with the availability of molecular markers that may lead to the earlier diagnosis of oral squamous cell carcinoma. This research aims to compare the efficacy of three different instruments (Cytobrush, curette and Oral CDx brush) in providing adequate material for molecular analysis. Methods: One hundred and four cytological samples obtained from volunteer healthy subjects were analysed using all three instruments. The clinical and demographical variables under study were age, sex and smoking habits. The three instruments were compared for their ability to obtain adequate samples and for the amount of RNA obtained using quantitative real‐time polymerase chain reaction (PCR‐qRT) analysis of the Abelson (ABL) housekeeping gene. Results: RNA of the ABL gene has been quantified by number of copies. Adequate samples were more likely to be obtained with a curette (90.6%) or Oral CDx (80.0%) than a Cytobrush (48.6%); P < 0.001. Similarly, the RNA quantification was 17.64 ± 21.10 with a curette, 16.04 ± 15.81 with Oral CDx and 6.82 ± 6.71 with a Cytobrush. There were statistically significant differences between the Cytobrush and curette (P = 0.008) and between the Cytobrush and OralCDx (P = 0.034). There was no difference according to the demographical variables. Conclusions: Oral exfoliative cytology is a simple, non‐invasive technique that provides sufficient RNA to perform studies on gene expression. Although material was obtained with all three instruments, adequate samples were more likely to be obtained with the curette or Oral CDx than with a Cytobrush. The Oral CDx is a less aggressive instrument than the curette, so could be a useful tool in a clinical setting.  相似文献   
922.
Cocoa sweatings, the pale yellowish liquid that drains off during cocoa fermentation, is the breakdown product of the mucilage surrounding the fresh cocoa bean, and constitutes about 10% of the weight of the cocoa fruit. On average, about 1.9 million l of sweatings are produced annually in Ghana during the cocoa harvesting season. It has been shown to be a suitable medium for the production of wines, alcohol, marmalade, jam and syrup. Its rapid collection in high yields and quality is the first step to its utilization on a commercial scale. Thus pure yeast culture fermentation of cocoa under controlled temperature conditions and its effect on yield of sweatings and final cocoa bean quality was investigated. Cocoa fermentations employing Saccharomyces chevalieri or Kluyveromyces fragilis alone gave significantly higher yields of sweatings (p 0.05) than controls. The initial rates of sweating by the two strains were also very high but dropped to a constant minimum value after 12h of fermentation. In contrast, fermentations employing Torulopsis candida or Candida norvengensis alone as well as different combinations of all the yeast strains did not give any significant difference in yield compared to controls (p 0.05). Fermentations using S. chevalieri alone or other combinations in which S. chevalieri was present gave beans with acceptable quality based on different quality indices used for grading cocoa beans commercially.  相似文献   
923.
Oral lichen planus (OLP) is a T cell–mediated immunoinflammatory disease. Glycolysis plays an essential role in T-cell immune responses. Blocking glycolytic pathway in activated T cells represents a therapeutic strategy for restraint of immunologic process in autoimmune disorders. 2-Deoxy-D-glucose (2-DG) has been widely used to probe into glycolysis in immune cells. This study was aimed to explore the role of glycolysis inhibition by 2-DG on regulating immune responses of OLP-derived T cells. We observed that lactic dehydrogenase A (LDHA) expression was elevated in OLP lesions and local T cells. 2-DG inhibited the expression of LDHA, p-mTOR, Hif1α and PLD2 in T cells; meanwhile, it decreased proliferation and increased apoptosis of T cells. T cells treated by 2-DG showed lower LDHA expression and elevated apoptosis, resulting in a reduced apoptotic population of keratinocytes that were co-cultured with them, which was related to the decreased levels of IFN-γ in co-culture system. Rapamycin enhanced the effects of 2-DG on immune responses between T cells and keratinocytes. Thus, these findings indicated that OLP-derived T cells might be highly dependent upon high glycolysis for proliferation, and 2-DG treatment combined with rapamycin might be an option to alleviate T-cell responses, contributing to reducing apoptosis of keratinocytes.  相似文献   
924.
The hypoglycemic activity of chromium methionine (CrMet) in alloxan-induced diabetic (AID) mice was investigated and compared with those of chromium trichloride hexahydrate (CrCl3·6H2O) and chromium nicotinate (CrNic) through a 15-day feeding experiment. The acute oral toxicity of CrMet was also investigated in ICR (Institute for Cancer Research) mice by a single oral gavage. The anti-diabetic activity of CrMet was explored in detail from the aspects of body weight (BW), blood glucose, triglyceride, total cholesterol, liver glycogen levels, aspartate transaminase (AST) and alanine transaminase (ALT) levels. The obtained results showed that CrMet had beneficial effects on glucose and lipid metabolism, and might possess hepatoprotective efficacy for diabetes. Daily treatment with 500 and 1000 μg Cr/kg BW of CrMet in AID mice for 15 days indicated that this low-molecular-weight organic chromium complex had better bioavailability and more beneficial effects on diabetics than CrCl3·6H2O. CrMet also had advantage over CrNic in the control of AST and ALT activities. Acute toxicity studies revealed that CrMet had low toxicity potential and relatively high safety margins in mice with the LD50 value higher than 10.0 g/kg BW. These findings suggest that CrMet might be of potential value in the therapy and protection of diabetes.  相似文献   
925.
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, affecting millions of individuals worldwide 1-3. The rapid, irregular, and disordered electrical activity in the atria gives rise to palpitations, fatigue, dyspnea, chest pain and dizziness with or without syncope 4, 5. Patients with AF have a five-fold higher risk of stroke 6.Oral anticoagulation (OAC) with warfarin is commonly used for stroke prevention in patients with AF and has been shown to reduce the risk of stroke by 64% 7. Warfarin therapy has several major disadvantages, however, including bleeding, non-tolerance, interactions with other medications and foods, non-compliance and a narrow therapeutic range 8-11. These issues, together with poor appreciation of the risk-benefit ratio, unawareness of guidelines, or absence of an OAC monitoring outpatient clinic may explain why only 30-60% of patients with AF are prescribed this drug 8.The problems associated with warfarin, combined with the limited efficacy and/or serious side effects associated with other medications used for AF 12,13, highlight the need for effective non-pharmacological approaches to treatment. One such approach is catheter ablation (CA), a procedure in which a radiofrequency electrical current is applied to regions of the heart to create small ablation lesions that electrically isolate potential AF triggers 4. CA is a well-established treatment for AF symptoms 14, 15, that may also decrease the risk of stroke. Recent data showed a significant decrease in the relative risk of stroke and transient ischemic attack events among patients who underwent ablation compared with those undergoing antiarrhythmic drug therapy 16.Since the left atrial appendage (LAA) is the source of thrombi in more than 90% of patients with non-valvular atrial fibrillation 17, another approach to stroke prevention is to physically block clots from exiting the LAA. One method for occluding the LAA is via percutaneous placement of the WATCHMAN LAA closure device. The WATCHMAN device resembles a small parachute. It consists of a nitinol frame covered by fabric polyethyl terephthalate that prevents emboli, but not blood, from exiting during the healing process. Fixation anchors around the perimeter secure the device in the LAA (Figure 1). To date, the WATCHMAN is the only implanted percutaneous device for which a randomized clinical trial has been reported. In this study, implantation of the WATCHMAN was found to be at least as effective as warfarin in preventing stroke (all-causes) and death (all-causes) 18. This device received the Conformité Européenne (CE) mark for use in the European Union for warfarin eligible patients and in those who have a contraindication to anticoagulation therapy 19.Given the proven effectiveness of CA to alleviate AF symptoms and the promising data with regard to reduction of thromboembolic events with both CA and WATCHMAN implantation, combining the two procedures is hoped to further reduce the incidence of stroke in high-risk patients while simultaneously relieving symptoms. The combined procedure may eventually enable patients to undergo implantation of the WATCHMAN device without subsequent warfarin treatment, since the CA procedure itself reduces thromboembolic events. This would present an avenue of treatment previously unavailable to patients ineligible for warfarin treatment because of recurrent bleeding 20 or other warfarin-associated problems.The combined procedure is performed under general anesthesia with biplane fluoroscopy and TEE guidance. Catheter ablation is followed by implantation of the WATCHMAN LAA closure device. Data from a non-randomized trial with 10 patients demonstrates that this procedure can be safely performed in patients with a CHADS2 score of greater than 1 21. Further studies to examine the effectiveness of the combined procedure in reducing symptoms from AF and associated stroke are therefore warranted.  相似文献   
926.
927.
Areca nut has been evaluated as a group I carcinogen to humans. However, the exact compounds of areca nut causing oral cancer remain unproven. Previous findings from our lab revealed that arecoline N-oxide (ANO), a metabolite of arecoline, exhibits an oral fibrotic effect in immune-deficient NOD/SCID mice. The aim of this study is to investigate the oral potentially malignant disorders (OPMD) inductive activity between areca-alkaloid arecoline and its metabolite ANO in C57BL/6 mice. Our findings show that ANO showed higher activity in inducing hyperplasia with leukoplakia and collagen deposition in C57BL/6 mice compared with the arecoline treated groups. Importantly, immunohistochemical studies showed significant upregulation of NOTCH1, HES1, FAT1, PCNA, and Ki67 expressions in the pathological hyperplastic part. In addition, in vitro studies showed that upregulation of NOTCH1 and FAT1 expressions in ANO treated HGF-1 and DOK cell models. We found that NOTCH1 regulates TP53 expression from NOTCH1 knockdown oral cancer cells. The DNA damage was significantly increased after arecoline and ANO treatment. Further, we found that arecoline-induced H2AX expression was regulated by FMO3. Altogether, our findings show that ANO exhibited higher toxicity in OPMD activity and play a significant role in the induction of areca nut mediated oral tumorigenesis.  相似文献   
928.
The aim of this study was to investigate sensitivity disorders in the oral cavity related to the presence of Mycobacterium leprae in the saliva of treatment-naïve patients with leprosy in the state of Amazonas, Brazil. A cross-sectional study was conducted involving 45 subjects with leprosy. The subjects were interviewed to evaluate the sensitivity of the oral cavity. For the detection of M. leprae, saliva and slit-skin smear samples were collected. The samples were analysed using a bacteriological index (BI) protocol and the real-time quantitative polymerase chain reaction (qPCR). The results indicated that 15 of the 45 (33.3%) subjects with leprosy showed decreased oral sensitivity, which confirmed the importance of the oral cavity sensitivity evaluation. There was not a direct relationship between the presence of M. leprae in saliva and changes in oral sensitivity. Positive saliva qPCR results from six (31.6%) of 19 paucibacillary (PB) patients suggested the possibility of a new site for sample collection. Positive results using these diagnostic techniques (BI, slit-skin smear and saliva qPCR) increased to 55.5%, thus opening the possibility of combining these different techniques to increase the rate of positive diagnoses, especially in PB patients.  相似文献   
929.
930.
All entomopathogenic fungi infect insects by direct penetration through the cuticle rather than per os through the gut. Genetic transformation can confer fungi with per os virulence. However, unless the recipient isolate is nonpathogenic to the target insect, mortality caused by a transgenic isolate cannot be attributed solely to oral virulence due to the potential for some simultaneous cuticular infection. Here, a Metarhizium anisopliae wild-type isolate (MaWT) nonpathogenic to Spodoptera litura was genetically engineered to provide a transformed isolate (MaVipT31) expressing the insect midgut-specific toxin Vip3Aa1. Toxin expression was confirmed in MaVipT31 hyphae and conidia using Western blotting. Mortality, leaf consumption and body weight of S. litura larvae (instars I–IV) exposed to a range of concentrations of MaWT conidia were not significantly different to controls although the number of conidia ingested by surviving larvae during the bioassay ranged from 2.3 × 105 (instar I) to 8.1 × 106 (instar IV). In contrast, consumption of MaVipT31 conidia caused high mortalities, reduced leaf consumption rates and decreased body weights in all instars evaluated, demonstrating that oral virulence had been acquired by MaVipT31. Larval mortalities were much more dependent on the number of MaVipT31 conidia ingested than the duration of time spent feeding on conidia-treated leaves (r2: 0.83–0.94 for instars I–IV). LC50 and LT50 trends for MaVipT31 estimated by time-concentration-mortality modeling analyses differed greatly amongst the instars. For 50% kill to be achieved, instar I larvae required 3, 4 and 5 days feeding on the leaves bearing 103, 28 and 8 conidia/mm2 respectively; instar IV larvae required 6, 7 and 8 days feeding on leaves bearing 1760, 730 and 410 conidia/mm2 respectively. Our results provide a deeper insight into the high oral virulence acquired by an engineered isolate and highlight its great potential for biological control.  相似文献   
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