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1.
Purpose: The aim of the paper was to develop the simple procedures for preparation of inclusion complexes of ellagic acid (EA) with cyclodextrins (CDs) and to investigate their antioxidant and antimicrobial activity.

Methods: The structural characterization was carried out using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and nuclear magnetic resonance (NMR) methods. The phase solubility technique was used to investigate the interactions between ‘host’ and ‘guest’ molecules and to estimate the molar ratio between them. The antioxidant and antimicrobial activity of EA and inclusion complexes were determined.

Results: The apparent stability constants were found to be 117?dm3 mol?1 for the complex with β-CD and 161?dm3 mol?1 for the complex with (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD). The results of phase-solubility studies showed that EA formed the inclusion complexes with CDs in the molar ratio of 1:1. The calculated half-maximal inhibitory concentration was 41.18?μg cm?3 for butyl hydroxy toluene, 1.96?μg cm?3 for EA, 0.88?μg cm?3 for inclusion complex with HP-β-CD, and 1.27?μg cm?3 for inclusion complex with β-CD.

Conclusion: The stability constants indicated the rapid release of EA from the inclusion complexes in the aqueous medium at 25?°C. The antioxidant activity of EA was increased, while the antimicrobial activity was preserved after complexation with CDs.  相似文献   

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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Das Bundesverfassungsgericht überprüft aktuell, ob das Vergabeverfahren der Medizinstudienplätze mit dem...  相似文献   
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A 41-year-old woman had a motor vehicle accident and sustained a fracture of the left temporal bone with anterior and middle skull base involvement. After 10 months, she developed persistent right-sided exophthalmus. Orbital computed tomography scans showed a soft tissue mass in the roof of the right orbit with an inferior calcified border. The surgery revealed a cerebrospinal fluid cyst with intracranial communication through the fistula in the posterior orbital roof.  相似文献   
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BACKGROUND: Severe forms of periodontitis are suggested to have a genetic basis. OBJECTIVE: The aim of the present investigation was to study the association of gene polymorphisms related to some immune regulation components (G-308A TNFA, Q551R IL-4RA and C-159T CD14) with severe chronic periodontitis. MATERIALS AND METHODS: Sixty patients (aged 36-74 years; mean 54.5+/-8.5) with severe and generalized chronic periodontitis were included. The patients exhibited bone loss >50% at all teeth. Thirty-nine periodontally healthy subjects between 35 and 78 years of age (mean 51.0+/-10.9) were recruited as controls. DNA was isolated from peripheral blood cells and genotyping was performed by combination of PCR and restriction endonuclease mapping. RESULTS: While gene polymorphisms for TNFA and IL-4RA did not show any association with severe chronic periodontitis, the analysis of the -159 CD14 gene polymorphism revealed significant differences between test and control groups. The proportion of subjects that exhibited the TT genotype was significantly smaller in the group with severe periodontitis than in periodontal healthy group (p=0.028; Fisher's exact test). The C allele carriage was 90% in the periodontitis group and significantly higher than in the healthy control group (72%). CONCLUSION: It is suggested that the -159 CD14 gene polymorphism is associated with chronic periodontitis in Caucasian subjects of a north European origin.  相似文献   
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PURPOSE: The study investigated the pattern of p53 gene mutations and human papillomavirus (HPV) infection concerning their relation to overall survival in patients with oral squamous cell carcinomas of the tongue and floor of the mouth. PATIENTS AND METHODS: The presence of HPV infection in 50 patients, and p53 gene mutations (42 patients from the same group) in the tumour specimens were analysed by polymerase chain reaction and single-stranded conformational polymorphism method. The follow-up period ranged from 12 to 48 (median 29) months. RESULTS: p53 mutations were identified in 11/42 tumours. HPV infection was detected in 32/50 cases, mostly HPV16 (10/32), HPV18 and HPV31 (6/32). A significantly higher incidence of HPV infection was found among smokers (p<0.05) and among patients with poor oral hygiene (p<0.01). The highest incidence of p53 mutations was detected in tumours of histological grade I and nuclear grade III. Patients with p53 mutation or with HPV infection had significantly shorter overall survival when compared with those that were without p53 mutations (p<0.01) or HPV infection (p<0.05). HPV-infected patients with p53 mutation had the worst prognosis when compared with patients with HPV infection only (p<0.01) or with patients negative for both HPV and p53 (p<0.01). CONCLUSION: The results stress once more the importance of HPV for the prognosis of survival of patients with squamous cell carcinoma of lower parts of the oral cavity. The presence of p53 mutations in HPV-infected tumours was associated with an even poorer prognosis for the patients.  相似文献   
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BACKGROUND: Severe forms of periodontitis are suggested to have a genetic basis. OBJECTIVE: The aim of the present investigation was to study association of an IL10 gene polymorphism (G to A transition at the -1087 position) with severe chronic periodontitis. MATERIALS AND METHODS: Two groups of Swedish Caucasian subjects were included. One group consisted of 60 patients (aged 36-74 years; mean 54.5+/-8.5) with severe and generalized chronic periodontitis. The patients exhibited bone loss >50% at all teeth. Thirty-nine periodontally healthy subjects between 35-78 years of age (mean 51.0+/-10.9) were also recruited. DNA was isolated from peripheral blood cells and genotyping was performed by combination of PCR with restriction endonuclease mapping. RESULTS: The proportion of subjects that exhibited the GG genotype was significantly larger in the group with severe periodontitis than in the periodontally healthy group. The difference regarding the occurrence of the GG genotype between the two groups was more conspicuous in non-smokers and yielded an odds ratio of 6.1. The G allele carriage in non-smokers was >90 % in the periodontitis group and was significantly higher than in the healthy controls. CONCLUSION: It is suggested that the -1087 IL10 polymorphism in Caucasian subjects of a north European origin is associated with severe chronic periodontitis.  相似文献   
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