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11.
Mechanism of fluconazole resistance in Candida albicans biofilms: phase-specific role of efflux pumps and membrane sterols 总被引:15,自引:0,他引:15 下载免费PDF全文
Candida albicans biofilms are formed through three distinct developmental phases and are associated with high fluconazole (FLU) resistance. In the present study, we used a set of isogenic Candida strains lacking one or more of the drug efflux pumps Cdr1p, Cdr2p, and Mdr1p to determine their role in FLU resistance of biofilms. Additionally, variation in sterol profile as a possible mechanism of drug resistance was investigated. Our results indicate that parent and mutant strains formed similar biofilms. However, biofilms formed by double and triple mutants were more susceptible to FLU at 6 h (MIC = 64 and 16 microg/ml, respectively) than the wild-type strain (MIC > 256 microg/ml). At later time points (12 and 48 h), all the strains became resistant to this azole (MIC > or = 256 microg/ml), indicating lack of involvement of efflux pumps in resistance at late stages of biofilm formation. Northern blot analyses revealed that Candida biofilms expressed CDR and MDR1 genes in all the developmental phases, while planktonic cells expressed these genes only at the 12- and 48-h time points. Functionality of efflux pumps was assayed by rhodamine (Rh123) efflux assays, which revealed significant differences in Rh123 retention between biofilm and planktonic cells at the early phase (P = 0.0006) but not at later stages (12 and 48 h). Sterol analyses showed that ergosterol levels were significantly decreased (P < 0.001) at intermediate and mature phases, compared to those in early-phase biofilms. These studies suggest that multicomponent, phase-specific mechanisms are operative in antifungal resistance of fungal biofilms. 相似文献
12.
Mahmoud Hassanein El-Saied A. Aly Yousf A. Abbas Samia M. El-Sigeny 《Macromolecular chemistry and physics.》1993,194(6):1817-1825
To overcome mass transfer limitations which are usually encountered on immobilizing active catalysts, cationic latex particles were used as support for the cobalt(II) complex of disodium N,N′-bis(salicylidene)ethylenediamine-5,5′-disulfonate ( 1 ). The cationic latex 2 was prepared by emulsion copolymerization of chloromethylstyrene (m/p-isomer mixture 60/40) and divinylbenzene (m/p-isomer mixture) followed by treatment with trimethylamine. The latexbound catalyst from 1 and 2 was found to considerably increase the reaction rate of the autoxidation of 2,6-di-tert-butylphenol in water as compared with the conventional polymer-free system. Reaction products were identified as the oxidative coupling product 3,3′,5,5′-tetra-tert-butyldiphenoquinone (3,3′,5,5′-tetra-tert-butyl-4,4′-dioxo-1,1′-bicyclohexa-2,5-dienylidene) and 2,6-di-tert-butyl-1,4-benzoquinone. All reactions showed an induction period before the start of dioxygen consumption. The rate of autoxidation in the three-phase mixtures of water, latex particles, and phenol droplets was not affected significantly by the method of mixing. The reaction rate increased as the concentration of 1 increased. Increasing the partial pressure of dioxygen in the range between 0,25 and 1,0 atm (2,53. 104 – 1,01. 105 Pa) gave a small increase in rate. The colloidal latex catalyst from 1 and 2 showed some loss of activity after successive runs. 相似文献
13.
Ahmed Hassan Albelbeisi Ali Albelbeisi Abdel Hamid El Bilbeisi Mahmoud Taleb Amirhossein Takian Ali Akbari-Sari 《Ethiopian journal of health sciences》2021,31(1):73
BackgroundDespite the huge numbers of the universally produced and employed protocols, the adherence with them is still low to moderate in the healthcare settings. This study was employed to assess the attitudes of Palestinian healthcare professionals in Gaza Strip to health education and counseling on healthy behaviours protocol (WHO-PEN Protocol 2), for patients with non-communicable diseases in the Ministry of Health primary healthcare centers.MethodsThis cross-sectional study was conducted with a census sample of all governmental family physicians and nurses (n=175). The study questionnaire was developed based on Cabana theoretical framework. The Arabic version questionnaire was developed based on the cross-cultural adaptation framework. The psychometric properties of the Arabic version questionnaire was finally evaluated.ResultsThe psychometric properties of the Arabic version questionnaire showed good construct validity and internal consistency reliability. The overall adherence level to WHO-PEN Protocol 2 was 70.0, SD=6.9. The main perceived barriers were lack of incentive, patients'' factors, and lack of time. In general, most of healthcare professional respondents had a positive attitude toward the protocol, but this attitude was not predictor to protocol adherence.ConclusionThe good validity and reliability of the questionnaire can provide support for the accuracy of the study results. Varied implementation strategies targeting the major barriers derived from the study are extremely required for addressing the lack of incentives, patients'' factors and time constraints. 相似文献
14.
15.
Dalia O. Mohamed Mona M. Sayed Islam F. Abdelkawi Mahmoud H. Elshoieby Salah M. Khallaf Lamia M. Khallaf Doaa M. Fouad 《Current Urology》2021,15(1):11
Background:Randomizing patients to bladder preservation or radical cystectomy (RC) for the treatment of bladder cancer has not been practical, due to patient and physician preferences. Therefore, continually comparing the 2 treatment modalities is needed, in order to make the proper choice for each patient.Patients and methods:The records of T1–4N0M0 bladder cancer patients, who presented to the South Egypt Cancer Institute between 2007 and 2017 and were treated by either bladder preservation or RC were reviewed.Results:Out of the 166 included patients, 81 (48.8%) patients were treated by bladder preservation and 85 (51.2%) patients had RC. For the patients treated by bladder preservation and the patients treated by RC, the 5-year overall survival (OS) was 56% and 60% (p = 0.67), the 5-year local recurrence-free survival was 69% and 73% (p = 0.69), and the 5-year disease-free survival was 45% and 53% (p = 0.16), respectively. After propensity matching analysis, the mean 5-year OS was 58% for the bladder preservation patients and 61% for the RC patients (p = 0.51). It is notable that among the bladder preservation group, 8 patients (10%) had squamous cell carcinoma (SCC) pathology and refused RC. Their OS was 56% compared to 53% for the SCC patients treated by RC (p = 0.6).Conclusion:Bladder preservation is a safe alternative to cystectomy in transitional cell carcinoma stages T1–4aN0M0, and its use in SCC bladder cancer should be further studied, as it could be feasible to spare them from initial cystectomy. 相似文献
16.
Mostafa M. Baraka Hany M. Hefny Mahmoud A. Mahran Tamer A. Fayyad Haytham Abdelazim Amr Nabil 《Journal of children's orthopaedics》2021,15(1):12
PurposeSurgical treatment in advanced-stage infantile Blount’s disease with medial plateau (MP) depression is challenging. Several osteotomies and fixation methods have been described with no established benchmark. We conducted this study to evaluate the efficacy and safety of a new single-stage technique for acute medial condyle elevation and metaphyseal osteotomies with internal fixation.MethodsA prospective case series of 19 consecutive patients (21 knees) with severe infantile Blount’s disease underwent a single-stage MP elevation and metaphyseal osteotomies, with internal fixation. The mean age was 10.3 years (8.2 to 13.6) and the mean follow-up was 5.1 years (3.2 to 8.3). The outcome measures included clinical and radiological parameters and patient-reported pediatric outcomes data collection instrument (PODCI) score.ResultsThe mean PODCI score improved significantly from 50% to 88%. The mean internal tibial torsion improved from -27° to 11°. All cases maintained full knee extension, no limitation in flexion range of movement and no signs of instability or lateral thrust gait. All the radiographic parameters improved significantly; the mean tibiofemoral angle improved from -29° to 7°, the metaphyseal-diaphyseal angle improved from 33.4° to 4.7° and the angle of depressed MP improved from 38.3° to 2.4° (p < 0.001). At the latest follow-up, no cases of deformity recurrence were identified, the final limb-length discrepancy was < 1 cm in all patients.ConclusionSingle-stage MP elevation and metaphyseal osteotomies with internal fixation significantly improved the clinical and radiographic parameters and PODCI score in advanced infantile Blount’s disease and precluded the use of external immobilization, with no evidence of deformity recurrence.Level of evidenceIV 相似文献
17.
Omar MT 《Archives of pharmacal research》1997,20(6):602-609
Some new 9H-thioxanthen-9-one incorporated into heterocyclic systems such as pyridone8, pyrazoline9, pyranone11, iminopyrane12, furopyrimidine17, imidazothiazole19, thiazole21, triazine24 and other related compounds through a para imminophenyl grouping at position-1 of the thioxanthenone ring were synthesized
and tested as antitumor agents, against L 1210 leukemia in mice. Some of the new compounds showed considerable antitumor activity. 相似文献
18.
Synthesis of 1-(heterocyclic substituted anilino)-9H-thioxanthon-9-ones and their antitumor activity
Omar MT 《Archives of pharmacal research》1997,20(6):610-619
Some new 9H-thioxanthen-9-one incorporated into heterocyclic systems such as pyridone8, pyrazoline9, pyranone11, iminopyrane12, furopyrimidine17, imidazothiazole19, thiazole21, triazine24 and other related compounds through a para imminophenyl grouping at position-1 of the thioxanthenone ring were synthesized and tested as antitumor agents, against L 1210 leukemia in mice. Some of the new compounds showed considerable antitumor activity. 相似文献
19.
The rapid rise in the number of the independent elderly persons in the community has become a world-wide phenomenon. Recently, more attention has been devoted to community based programs for the elderly. One type of these programs offering multiple services is the elderly clubs. These clubs may provide health and physical care beside social interaction and peer group support for the independent elderly in the community. In Alexandria, elderly health and social care provided are not coping with the increasing numbers of the aged population and consequently with their needs and problems. So the aim of this study was to describe the health profile of the consumers of the elderly clubs in Alexandria and to determine the preferred activities needed by the consumers of the elderly clubs in Alexandria. To fulfil this aim, a sample of 163 elderly representing the consumers from all (five) elderly clubs in Alexandria were interviewed. The results revealed that almost one third (30.67%) of the elderly consumers had no health complaints, 35.58% had only one health complaint and 33.74% had more than one complaint. The most health complaints stated by the consumers were cardiovascular diseases/hypertension followed by diabetes mellitus then rheumatic diseases/arthritis. The results also revealed that all the elderly consumers had one or more minor signs and symptoms during the last six months of the interview. These signs and symptoms varied from amnesia, low concentration, constipation, dizziness and dyspepsia. The majority of the elderly consumers preferred the recreational trips and attending religious seminars/reading Quraan. Walking and checking on blood pressure were the most preferred activities mentioned by nearly half the consumers. The results of this study can be considered as a base line data to help policy makers in taking decisions during planning and providing the needed services to the elderly. 相似文献
20.