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doi: 10.1111/j.1741‐2358.2011.00544.x Comparison of therapeutic effect of aqueous extract of garlic and nystatin mouthwash in denture stomatitis Introduction: Denture stomatitis (DS) is the most common form of chronic oral candidiasis. The standard treatment for DS is nystatin, which is accompanied with complications such as a bitter taste. The aim of this study was to compare the effect of garlic with nystatin in DS. Material and Methods: This randomised clinical trial study was performed on 40 patients with DS. After obtaining written consent, patients were divided into two groups while members of each group were given either nystatin or garlic extract for 4 weeks. The length and width of erythema area was measured at the end of the first, second, third, and the fourth weeks using a calliper. Data were analysed by SPSS and statistical tests including variance analysis with anova repeated measures, chi‐square, and least square differences. Results: The changes in the length and width of erythema at different times according to the type of treatment were found to be significant while an accelerated recovery was demonstrated for nystatin (p < 0.001). Both regimens resulted in significant recovery (p < 0.0001). Greater satisfaction with the use of garlic rather than nystatin was mentioned (p < 0.0001). Conclusion: Considering the efficacy of garlic and lack of side effects for this compound and also regarding the nystatin‐associated complications, garlic extract can be introduced as a substitution for standard treatment in DS.  相似文献   
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The microenvironment of cancerous cells includes endoplasmic reticulum (ER) stress the resistance to which is required for the survival and growth of tumors. Acute ER stress triggers the induction of a family of ER stress proteins that promotes survival and/or growth of the cancer cells, and also confers resistance to radiation and chemotherapy. Prolonged or severe ER stress, however, may ultimately overwhelm the cellular protective mechanisms, triggering cell death through specific programmed cell death (pcd) pathways. Thus, downregulation of the protective stress proteins may offer a new therapeutic approach to cancer treatment. In this regard, recent reports have demonstrated the roles of the phytochemical curcumin in the inhibition of proteasomal activity and triggering the accumulation of cytosolic Ca2+ by inhibiting the Ca2+-ATPase pump, both of which enhance ER stress. Using a mouse melanoma cell line, we investigated the possibility that curcumin may trigger ER stress leading to programmed cell death. Our studies demonstrate that curcumin triggers ER stress and the activation of specific cell death pathways that feature caspase cleavage and activation, p23 cleavage, and downregulation of the anti-apoptotic Mcl-1 protein.  相似文献   
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ObjectiveTo examine the effect of ethnicity on the relation between tuberculosis and deprivation.DesignRetrospective ecological study comparing incidence of tuberculosis in white and south Asian residents of the 39 electoral wards in Birmingham with ethnic specific indices of deprivation.SettingBirmingham, 1989-93.Subjects1516 notified cases of tuberculosis.ResultsUnivariate analysis showed significant associations of tuberculosis rates for the whole population with several indices of deprivation (P<0.01) and with the proportion of the population of south Asian origin (P<0.01). All deprivation covariates were positively associated with each other but on multiple regression, higher level of overcrowding was independently associated with tuberculosis rates. For the white population, overcrowding was associated with tuberculosis rates independently of other variables (P=0.0036). No relation with deprivation was found for the south Asian population in either single or multivariable analyses.ConclusionsPoverty is significantly associated with tuberculosis in the white population, but no such relation exists for those of Asian ethnicity. These findings suggest that causal factors, and therefore potential interventions, will also differ by ethnic group.

Key messages

  • Previous studies in the United Kingdom have been unable to disentangle the effects of poverty and ethnicity on the incidence of tuberculosis
  • A strong relation was found between measures of poverty and tuberculosis in the white population
  • No relation between measures of poverty and tuberculosis was found in the Asian population
  • The only measure of poverty independently associated with tuberculosis in the white population is overcrowding
  • An increasing proportion of tuberculosis is occurring in Asian people and causal factors in this group are likely to be different from those in the white population
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Background

Expansion of the C9orf72 hexanucleotide repeat (GGGGCC)n·(GGCCCC)n is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Both strands of the C9orf72 repeat have been shown to form unusual DNA and RNA structures that are thought to be involved in mutagenesis and/or pathogenesis. We previously showed that the C-rich DNA strands from the C9orf72 repeat can form four-stranded quadruplexes at neutral pH. The cytosine residues become protonated under slightly acidic pH (pH?4.5–6.2), facilitating the formation of intercalated i-motif structures.

Methods

Using CD spectroscopy, UV melting, and gel electrophoresis, we demonstrate a pH-induced structural transition of the C-rich DNA strand of the C9orf72 repeat at pHs reported to exist in living cells under stress, including during neurodegeneration and cancer.

Results

We show that the repeats with lengths of 4, 6, and 8?units, form intercalated quadruplex i-motifs at low pH (pH?<?5) and monomolecular hairpins and monomolecular quadruplexes under neutral-basic conditions (pH?≥?8). Furthermore, we show that the human replication protein A (RPA) binds to the G-rich and C-rich DNA strands under acidic conditions, suggesting that it can bind to i-motif structures.

Conclusions

In the proper sequence context, i-motif structures can form at pH values found in some cells in vivo.

General significance

DNA conformational plasticity exists over broad range of solution conditions.  相似文献   
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During two growing seasons (2008 and 2009), the associations of Rhizoctonia root rot (RRR) with a number of soil properties were determined at different growth stages in 122 commercial bean fields in Zanjan, Iran. Mean RRR incidence at a level of 4–25% sand content was lower than that at 45–65% level. Damage by fly puparia had no significant effect on RRR incidence and occurrence. A greater RRR incidence was detected in field soils treated with fungicides compared with non‐treated soils. A lower RRR incidence was associated with the highest level of soil organic matter (1.2–1.8) compared with the lowest level, 0.4–0.8. The highest RRR incidence corresponded with no rhizobial nodulation compared with highly nodulated bean roots. RRR incidence was negatively correlated with soil silt and organic matter content at R6–7 and R9 growth stages. RRR‐affected fields were recognized with a greater soil pH (V3) and sand content (R9), and a lower silt (R9) and organic matter content (R6–7 and R9) in comparison with RRR‐free fields. Loadings and linear regressions between RRR incidence and principal component scores indicated that the most effective soil characteristic linked to the disease was silt at V3, sand at R6–7 and organic matter at R9 stage. This new epidemiological information extends our knowledge of the bean–RRR–soil interaction on a regional basis.  相似文献   
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