共查询到20条相似文献,搜索用时 31 毫秒
1.
Jukka H. Meurman Pirjo Pärnänen C. Jaya Seneviratne Lakshman P. Samaranayake Antti M. J. Saarinen Kirsti Kari 《Gerodontology》2011,28(4):246-252
doi: 10.1111/j.1741‐2358.2010.00407.x Prevalence and antifungal drug sensitivity of non‐albicans Candida in oral rinse samples of self‐caring elderly Aim: To assess the prevalence and antifungal drug sensitivity of non‐albicans Candida (NAC) species in elderly outpatients. Materials and methods: We investigated oral rinse samples of 194 self‐caring elderly population (mean age 83 years) with emphasis on background factors for harbouring NAC. Susceptibility of Candida species to antifungal drugs was determined using standard methodology. Multiple logistic regression analysis was performed taking positive NAC count as the dependent variable and a number of known Candida risk factors as independent variables. Results: Prevalence of candidal carriage of the population was 78.4%, of which 0.5% of the subjects were NAC positive. Candida dubliniensis was the most prevalent NAC species, followed by Candida glabrata and Candida parapsilosis. The NAC positive elderly were more often edentulous with dental prostheses or had fewer teeth than Candida albicans‐positive or yeast‐negative subjects. Dental caries slightly increased the risk for having NAC strains (odds ratio 1.08), whilst greater age appeared to lower the risk (odds ratio 0.77). Candida species were susceptible to the commonly used antifungal agents in general, but with considerable variation among species. Occasionally, some NAC exhibited lower antifungal susceptibility. Conclusion: The possibility of oral reservoirs of NAC strains which are resistant to common antifungals should be noted in elderly outpatients. 相似文献
2.
Objective: The aim of this study was to examine differences in plaque accumulation in elderly patients using two toothpastes, with either 0.2% sodium fluoride (NaF) or 0.4% stannous fluoride (SnF2), but otherwise identical. Background data: The prevalence of denate elderly is increasing. Plaque both causes caries and is associated with an increased mortality rate in frail elderly patients with pneumonia. Therefore, the effective removal of plaque is important. Ingredients with an anti‐plaque effect, such as SnF2, that can be used in toothpaste, are effective in plaque inhibition Materials and methods: Thirty‐two frail elderly women, 82–98 years of age (mean, 88 years) and living in a residential home, participated in a double‐blind crossover study. They brushed their teeth for 4 weeks with each toothpaste. Treatment outcome was a change in the plaque index (PI) on four anterior teeth and four molars. Results: anova showed statistically significant differences between the treatments (F = 4.21, p = 0.02). A post hoc test showed that SnF2 produced a statistically significantly lower PI than did NaF. Conclusion: SnF2 in toothpaste may be effective in inhibiting plaque accumulation in the elderly. 相似文献
3.
Aims: To evaluate and compare remineralisation of root caries lesions after in vitro treatment with various fluoride (F) agents using an Electric Caries Monitor (ECM) and Transversal Micro‐Radiography (TMR). Materials: Permanent human teeth were extracted and root surface specimens were sectioned, prepared (n = 35), and randomly allocated into seven different experimental groups (groups 1–7). Methods: Root surfaces were demineralised in an acidified gel (pH = 5.0) for 3 weeks followed by various F treatments and stored in a standardised remineralising solution at 37°C for 6 weeks. The root surfaces were treated twice daily with different dentifrice slurries for 2 min, either with a neutral placebo dentifrice without F (group 5); or a neutral sodium fluoride (NaF) 1400 p.p.m. F dentifrice (group 1); or a neutral 1250 p.p.m. F dentifrice (group 6); or an acid dentifrice (pH 4.7) with 1400 p.p.m. F containing amine fluoride (AmF) (groups 3 and 4) or a 1250 p.p.m. (pH 4.7) AmF dentifrice (group 6). In groups 1, 2, 5, 6, and 7, the root surfaces were additionally rinsed for 2 min with a neutral non‐F placebo solution. In groups 3 and 4, rinsing were performed for 2 min with an acid (pH 4.7) 250 p.p.m. F solution, containing 125 p.p.m. F as AmF and 125 p.p.m. F as potassium fluoride (KF), once or twice per day respectively. ECM was used to measure electrical resistance on root surfaces at baseline and after 3 and 6 weeks respectively. TMR technique was used to measure and compare root surface lesion depths and mineral loss. Results: Six weeks daily treatment with a dentifrice slurry containing AmF followed by rinsing with a combination of equal amounts of AmF and KF solution twice a day showed a statistical significant higher ECM values compared with the other groups. TMR data measuring lesion depths and mineral loss reduction supported the results of the ECM findings. Conclusions: Daily application of a dentifrice slurry containing 1400 p.p.m. F as AmF combined with twice daily rinsing with a 250 p.p.m. F solution containing equal amount of AmF and KF significantly remineralise primary root caries lesions in vitro. ECM and TMR are valuable complementary methods in order to analyse the remineralisation processes. 相似文献
4.
Objectives: Few epidemiological studies have confirmed the antifungal activity of histatin 5 in saliva against Candida species. The purpose of this study was to examine the relationship between concentrations of histatin 5 and the number of cultivable Candida in saliva samples from elderly. Methods: Whole saliva samples were obtained from 124 elderly people, 65 years or older, living in a rural community. The concentrations of histatin 5 in saliva samples were determined by the enzyme‐linked immunosorbent assay (ELISA) using a monoclonal antibody. Total colony‐forming units (CFUs) were counted on a selective medium for Candida. Multiple linear regression analysis was performed to determine the independent contribution of explanatory variables to Candida CFUs using age, sex, histatin 5 concentration and type of denture prosthesis as independent variables. Results: Saliva samples from 104 subjects (84%) were candidal colony‐positive. The youngest group (65–69 years old) showed significantly smaller Candida CFU counts than those in the older group. The mean Candida CFU count of denture wearers was significantly higher than that of non‐denture wearers. Significantly negative associations were found between Candida CFU counts and histatin 5 level in the oldest group (p < 0.05) and in the full‐denture wearers (p < 0.01). Multiple linear regression analysis revealed that Candida CFU counts were mostly associated with type of dentures, followed by histatin 5 concentration. Conclusion: Possible activity of histatin 5 against Candida in whole saliva of elderly people was epidemiologically confirmed. The area covered by the prostheses was a strong factor associated with the Candida CFU count. 相似文献
5.
Junko Kawashima Kazuko Nakajo Jumpei Washio Gen Mayanagi Hidetoshi Shimauchi Nobuhiro Takahashi 《Microbiology and immunology》2013,57(12):797-804
Actinomyces are predominant oral bacteria; however, their cariogenic potential in terms of acid production and fluoride sensitivity has not been elucidated in detail and compared with that of other caries‐associated oral bacteria, such as Streptococcus. Therefore, this study aimed to elucidate and compare the acid production and growth of Actinomyces and Streptococcus in the presence of bicarbonate and fluoride to mimic conditions in the oral cavity. Acid production from glucose was measured by pH‐stat at pH 5.5 and 7.0 under anaerobic conditions. Growth rate was assessed by optical density in anaerobic culture. Although Actinomyces produced acid at a lower rate than did Streptococcus, their acid production was more tolerant of fluoride (IDacid production 50 = 110–170 ppm at pH 7.0 and 10–13 ppm at pH 5.5) than that of Streptococcus (IDacid production 50 = 36–53 ppm at pH 7.0 and 6.3–6.5 ppm at pH 5.5). Bicarbonate increased acid production by Actinomyces with prominent succinate production and enhanced their fluoride tolerance (IDacid production 50 = 220–320 ppm at pH 7.0 and 33–52 ppm at pH 5.5). Bicarbonate had no effect on these variables in Streptococcus. In addition, although the growth rate of Actinomyces was lower than that of Streptococcus, Actinomyces growth was more tolerant of fluoride (IDgrowth 50 = 130–160 ppm) than was that of Streptococcus (IDgrowth 50 = 27–36 ppm). These results indicate that oral Actinomyces are more tolerant of fluoride than oral Streptococcus, and bicarbonate enhances the fluoride tolerance of oral Actinomyces. Because of the limited number of species tested here, further study is needed to generalize these findings to the genus level. 相似文献
6.
Joost te Riet Inge Reinieren‐Beeren Carl G. Figdor Alessandra Cambi 《Journal of molecular recognition : JMR》2015,28(11):687-698
The fungus Candida albicans is the most common cause of mycotic infections in immunocompromised hosts. Little is known about the initial interactions between Candida and immune cell receptors, such as the C‐type lectin dendritic cell‐specific intracellular cell adhesion molecule‐3 (ICAM‐3)‐grabbing non‐integrin (DC‐SIGN), because a detailed characterization at the structural level is lacking. DC‐SIGN recognizes specific Candida‐associated molecular patterns, that is, mannan structures present in the cell wall of Candida. The molecular recognition mechanism is however poorly understood. We postulated that small differences in mannan‐branching may result in considerable differences in the binding affinity. Here, we exploit atomic force microscope‐based dynamic force spectroscopy with single Candida cells to gain better insight in the carbohydrate recognition capacity of DC‐SIGN. We demonstrate that slight differences in the N‐mannan structure of Candida, that is, the absence or presence of a phosphomannan side chain, results in differences in the recognition by DC‐SIGN as follows: (i) it contributes to the compliance of the outer cell wall of Candida, and (ii) its presence results in a higher binding energy of 1.6 kBT. The single‐bond affinity of tetrameric DC‐SIGN for wild‐type C. albicans is ~10.7 kBT and a dissociation constant kD of 23 μM, which is relatively strong compared with other carbohydrate–protein interactions described in the literature. In conclusion, this study shows that DC‐SIGN specifically recognizes mannan patterns on C. albicans with high affinity. Knowledge on the binding pocket of DC‐SIGN and its pathogenic ligands will lead to a better understanding of how fungal‐associated carbohydrate structures are recognized by receptors of the immune system and can ultimately contribute to the development of new anti‐fungal drugs. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
7.
Mario C. S. Oliveira Viviane M. B. Oliveira Alex C. Vieira Isabel Rambob 《Gerodontology》2010,27(4):303-307
doi: 10.1111/j.1741‐2358.2009.00345.x In vivo assessment of the effect of an adhesive for complete dentures on colonisation of Candida species Objective: Denture adhesives have long been recognised by denture wearers as a useful adjunct to denture retention and stability. The objective of the present study was to evaluate, in vivo, the effect of a denture adhesive on oral quantities of Candida species by determination of absolute counts of colony‐forming units (CFU) per ml of saliva of individuals who use this denture adhesive for a period of 14 days. Materials and methods: Twenty‐four individuals were randomised in two equal groups of 12 (test and control), with the individuals of the test group using the adhesive for 14 days. Samples of saliva were collected from all individuals on days 0 (initial), 7 and 14. Aliquots of saliva were diluted and plated in duplicate on Sabouraud dextrose agar with chloramphenicol and incubated for 37°C for 48 h, the CFU/ml were counted in the individuals of each group and the data of each group were compared at the different time periods and analysed statistically by the non‐parametric Mann‐Whitney U‐test (α ≤ 5%). Results: There were no statistically significant differences between the test and control groups during the test periods. Conclusion: Within of the limitations of this study, the data suggested that the denture adhesive tested did not significantly alter the oral microbiota during the 14‐day trial period. 相似文献
8.
Mustafa Murat Mutluay Serra Oğuz Dag Ørstavik Finn Fløystrand Arife Doğan Eva Söderling Timo Närhi Ingar Olsen 《Gerodontology》2010,27(4):283-291
doi:10.1111/j.1741‐2358.2009.00329.x Experiments on in vivo biofilm formation and in vitro adhesion of Candida species on polysiloxane liners Objectives: Microorganisms may colonise polysiloxane soft liners leading to bio‐deterioration. The aim of this study was to investigate in vitro adhesion and in vivo biofilm formation of Candida species on polysiloxane surfaces. Methods: The materials used in this study were Molloplast B, GC Reline soft, Mollosil Plus, Silagum Comfort and Palapress Vario. The in vitro retention of clinical isolates of Candida albicans to the relining and denture‐base materials by microscopic (scanning electron microscopy, SEM), conventional culturing methods and antimicrobial properties of these materials were studied. Candida found on materials and mucosa following long‐term use were identified and quantified, and biofilms covering the surfaces were investigated by SEM. Results: There was a significant decrease in the number of cells attached in vitro to saliva‐coated surfaces compared with non‐treated surfaces. An oral Candida carriage of 78% was found. Candida albicans, C. glabrata, C. intermedia and C. tropicalis were identified. In vivo biofilm formation on the liners appeared as massive colonisation by microorganisms. Conclusions: The results of the in vitro experiments suggest that salivary film influences early colonisation of different C. albicans strains. The film layer also minimises the differences among different strains. The Candida carriage of these patients was similar to denture‐wearing patients without soft liners. 相似文献
9.
Wang J Ohshima T Yasunari U Namikoshi S Yoshihara A Miyazaki H Maeda N 《Gerodontology》2006,23(3):157-163
Objectives: To screen the carriage status of Candida species, especially Candida albicans and its genotype in an epidemiological survey and to investigate its correlation with the dental, periodontal and prosthetic status of healthy elderly subjects. Materials and methods: Microbiological samples were collected from the dorsum of the tongue of 366 subjects, aged 75, and cultured on CHROMagar medium. The carriage status of Candida spp. and the distribution of C. albicans genotypes by a polymerase chain reaction (PCR) method were analysed and compared with the dental, periodontal and prosthetic status of the subjects. Results: A high carriage rate (68.6%) of Candida spp. and the predominant species of C. albicans (72.1%) were found in this study. The prevalence, density and multi‐species of Candida spp. were significantly related to the presence of a dental prosthesis. In C. albicans, genotype A predominated (56.4%) and genotype D showed a higher prevalence (12.5%) than previous reports. When comparing Candida spp. carriage with the oral status, significant positive correlations were found with the presence of any dental prosthesis, missing teeth, the number of retained roots and the percentage of sites showing bleeding on probing (BOP), while significant negative correlations were found with the number of teeth present, sound and filled teeth. Conclusions: Candida carriage on the dorsum of the tongue in healthy elderly is significantly associated with the dental, periodontal and prosthetic status, especially the presence of a dental prosthesis. As the complexity of the prosthesis being worn increased, the relative risk of Candida carriage and the numbers and multi‐species of Candida increased accordingly. 相似文献
10.
Three virulence factors comprising proteinase, phospholipase, and biofilm among 68 Candida albicans and 31 non-albicans Candida strains (11 C. tropicalis, 8 C. parapsilosis, 6 C. glabrata, 4 C. guillermondii, 2 C. krusei) isolated from blood cultures were analyzed. In total, 61 (89.7%) C. albicans strains were detected as proteinase positive whereas eight (25.8%) non-albicans Candida strains were proteinase positive (P < 0.05). Phospholipase production was detected in 41 (60.3%) C. albicans strains. All non-albicans Candida strains were phospholipase negative. Biofilm production was determined by both visual and spectrophotometric methods. Eight
(11.8%) of C. albicans strains and 13 (41.93%) of 31 non-albicans Candida strains were biofilm positive with two of the methods (P < 0.05). According to our results, we may suggest that detection of hydrolytic enzyme and biofilm production abilities of
the Candida isolates in clinical mycology laboratories may warn the clinican for a possible hematogenous infection. 相似文献
11.
Metin DY Hilmioglu-Polat S Samlioglu P Doganay-Oflazoglu B Inci R Tumbay E 《Mycopathologia》2011,172(3):187-199
Candida species that show an increasing number of clinical and/or microbiological resistance to several antifungals and are the most
common agents of invasive fungal infections. The aim of this study was to investigate the in vitro susceptibility of Candida blood isolates to antifungal agents (amphotericin B, fluconazole, itraconazole, and voriconazole) by comparative use of the
CLSI reference microdilution method and Etest. Four hundred Candida blood isolates (215 Candida
albicans, 185 non-albicans
Candida strains) were included in the study. The broth microdilution test was performed according to the CLSI M27 A2 document. Etest
was carried out according to the manufacturer’s instructions. The MIC results obtained with reference microdilution were compared
with those obtained with the Etest by using percent and categorical agreements. According to MIK90 values, voriconazole was the most active and itraconazole was the least active drug in vitro against all Candida species. Other than voriconazole, statistically significant differences were found when the susceptibility of Candida albicans and non-albicans Candida spp. to amphotericin B, fluconazole, and itraconazole were compared. These antifungal agents were found to be more active
to C. albicans. Among the non-albicans
Candida species, the lowest MIC values were obtained for Candida parapsilosis isolates. When the standard method was compared with Etest, the total agreement was higher for C. albicans than for non-albicans species, especially for fluconazole and voriconazole. In view of the findings, it was concluded that itraconazole showed
the lowest activity against all Candida species. Etest could be an alternative method in assessing the in vitro antifungal susceptibility of Candida spp., but it is more convenient to use the microdilution method for studying in vitro susceptibility of non-albicans species, in particular for those possessing high MIC values against azoles. 相似文献
12.
The aim of this study was to investigate oral yeast colonization, antifungal susceptibility and strain diversity in insulin-dependent
diabetes mellitus patients (175), as well as to evaluate the influence of dental prostheses. Oral rinse samples were cultured
on selective media, in order to isolate, count and identify the yeasts recovered. More than half of the diabetic subjects
(53%) carried significant amounts of Candida cells in the buccal cavity and these organisms were recovered at higher densities in diabetics wearing dentures. A total
of 93 yeast strains were isolated from these patients, including: Candida spp. (n = 89); Pichia (n = 02); Trichosporon (n = 1), and Geotrichum (n = 1). C. albicans represented 56% of these strains, non-albicans Candida 39.8%, and other genera of yeast 4.3%. C. albicans was prevalent, followed by C. parapsilosis, C. tropicalis, C. glabrata, C. krusei, C. rugosa and C. guilliermondii. Agar disk-diffusion tests of the susceptibility of non-albicans Candida and other genera of yeast to fluconazole showed resistance in 21.9%, mainly in C. rugosa (100%), C. glabrata (57%) and C. krusei (50%). Local oral factors, such as the presence of dentures, in association with diabetes, seemed to have the effect of increasing
the amount and variety of Candida species in the oral cavities, mainly those with lower drug susceptibilities. 相似文献
13.
Back-Brito GN Mota AJ Vasconcellos TC Querido SM Jorge AO Reis AS Balducci I Koga-Ito CY 《Mycopathologia》2009,167(2):81-87
The aim of this study was to evaluate the prevalence of Candida spp., and particularly C. dubliniensis, among oral isolates from Brazilian HIV-positive patients correlating these results with CD4 cell counts and viral load.
Forty-five individuals (23 female and 22 male) diagnosed as HIV-positive by ELISA and Western-blot, under anti-retroviral
therapy for at least 1 year and without oral candidosis signals were included in the study. The control group was constituted
by 45 healthy individuals, matched to the test group in relation to age, gender, and oral conditions. Oral rinses were collected
and the identification was performed by phenotypic tests. The existence of C. dubliniensis among the isolates was analyzed using a validated multiplex PCR assay. Candida spp. were detected at significantly higher number in the oral cavity of HIV-positive patients in relation to the controls
(P = 0.0008). C. albicans was the most frequently isolated species in both groups. In the HIV group, C. glabrata, C. lipolytica, C. krusei, C. guilliermondii, and C. parapsilosis were also identified. In the control group, we additionally identified C. tropicalis and C. dubliniensis. Two isolates (1.9%, 2/108) from control individuals were identified as C. dubliniensis and this species was not verified in the HIV group. Candida spp. counts were statistically lower (P = 0.0230) in the oral cavity of patients with low viral load (<400 copies/mm3). Candida spp. counts did not differ statistically among groups with different levels of CD4 cells counts (P = 0.1068). 相似文献
14.
Thiele MC Carvalho Ade P Gursky LC Rosa RT Samaranayake LP Rosa EA 《Gerodontology》2008,25(4):229-236
Material and methods: Fifty nine elders wearing complete dentures and living in retirement homes in Curitiba (southern Brazil), were divided into two groups: group #1, 26 patients with denture‐induced stomatitis and group #2, 33 patients without denture‐induced stomatitis. The two groups were evaluated in relation to the degree of denture‐induced stomatitis, salivary fungal loads, and secretion of some histolytic enzymes. Results: Patients from group #1 showed higher degrees of colonisation by Candida albicans (p = 0.031). Candida krusei, Candida tropicalis, and Candida parapsilosis were also isolated, but there were no differences between the groups (p > 0.05). Secretory aspartyl protease (Sap) and chondroitinase did not show significant differences among the isolated Candida spp. in the two groups. Phospholipase secretion rates were higher among the strains of C. albicans from group #2 (p = 0.036). The same behaviour was not detected for non‐albicans Candida species. Conclusions: The results could infer that differences in the secretion rates of candidal histolytic enzymes should not be imputed as imperative for the progress of denture‐induced stomatitis. 相似文献
15.
K. Hirota H. Yumoto B. Sapaar T. Matsuo T. Ichikawa Y. Miyake 《Journal of applied microbiology》2017,122(2):321-330
Candida albicans is a commonly found member of the human microflora and is a major human opportunistic fungal pathogen. A perturbation of the microbiome can lead to infectious diseases caused by various micro‐organisms, including C. albicans. Moreover, the interactions between C. albicans and bacteria are considered to play critical roles in human health. The major biological feature of C. albicans, which impacts human health, resides in its ability to form biofilms. In particular, the extracellular matrix (ECM) of Candida biofilm plays a multifaceted role and therefore may be considered as a highly attractive target to combat biofilm‐related infectious diseases. In addition, extracellular DNA (eDNA) also plays a crucial role in Candida biofilm formation and its structural integrity and induces the morphological transition from yeast to the hyphal growth form during C. albicans biofilm development. This review focuses on pathogenic factors such as eDNA in Candida biofilm formation and its ECM production and provides meaningful information for future studies to develop a novel strategy to battle infectious diseases elicited by Candida‐formed biofilm. 相似文献
16.
Luc De Visschere Jos Schols Gert‐Jan van der Putten Cees de Baat Jacques Vanobbergen 《Gerodontology》2012,29(2):e96-e106
doi: 10.1111/j.1741‐2358.2010.00418.x Effect evaluation of a supervised versus non‐supervised implementation of an oral health care guideline in nursing homes: a cluster randomised controlled clinical trial Objective: To compare a supervised versus a non‐supervised implementation of an oral health care guideline in Flanders (Belgium). Background: The key factor in realising good oral health is daily oral hygiene care. In 2007, the Dutch guideline ‘Oral health care in care homes for elderly people’ was developed to improve oral health of institutionalised elderly. Materials and Methods: A random sample of 12 nursing homes was randomly allocated to the intervention or the control group. Representative samples of 30 residents in each home were monitored during a 6‐month study period. The intervention included a supervised implementation of the guideline. Results: At the 6‐month follow‐up, only a small but statistically significant (p = 0.002) beneficial effect (0.32) of the intervention was observed for denture plaque after adjustment for baseline value and the random effect of the institution. In the linear mixed regression models, including a random institution effect, difference in denture plaque level was no longer statistically significant at the 5% level. Conclusion: Only denture hygiene has been improved by the supervised implementation, although with lower benefits than presumed. Factors on institutional level, difficult to assess quantitatively, may play an important role in the final result. 相似文献
17.
CHROMagar has been reported to be useful for the rapid and accurate identification of Candida species. We tested 135 isolates of Candida species isolated from oropharyngeal candidiasis in HIV patients and found that it was useful in the presumptive identification
of Candida albicans and Candida krusei. Occasional strains of C. tropicalis produced colonies with a greenish tinge making it difficult to differentiate from C. albicans. 相似文献
18.
Sanjeev Dhawan Paul Awolade Prishani Kisten Nosipho Cele Ashona‐Singh Pillay SouravTaru Saha Mandeep Kaur Sreekantha B. Jonnalagadda Parvesh Singh 《化学与生物多样性》2020,17(1)
A series of coumarin‐tagged β‐lactam triazole hybrids ( 10a – 10o ) were synthesized and tested for their cytotoxic activity against MDA‐MB‐231 (triple negative breast cancer), MCF‐7 (estrogen receptor positive breast cancer (ER+)) and A549 (human lung carcinoma) cancer cell lines including one normal cell line, HEK‐293 (human embryonic kidney). Two compounds 10b and 10d exhibited substantial cytotoxic effect against MCF‐7 cancer cell lines with IC50 values of 53.55 and 58.62 μm , respectively. More importantly, compounds 10b and 10d were non‐cytotoxic against HEK‐293 cell lines. Structure–activity relationship (SAR) studies suggested that the nitro and chloro group at the C‐3 position of phenyl ring are favorable for anticancer activity, particularly against MCF‐7 cell lines. Furthermore, antimicrobial evaluation of these compounds revealed modest inhibition of examined pathogenic strains with compounds 10c and 10i being the most promising antimicrobial agents against Pseudomonas aeruginosa and Candida albicans, respectively. 相似文献
19.
Objectives: The effect of multiple daily applications of a prophylactic gel, with buffering substances, on plaque acidogenicity in elderly institutionalised individuals was evaluated. Background: Many elderly suffer from reduced salivary flow, poor oral hygiene and increased levels of cariogenic bacteria and are considered to be at an increased risk for coronal and root caries. Reinforcing the buffering capacity of dental plaque by the addition of substances such as bicarbonate and phosphates may decrease their caries activity. Materials and methods: Fourteen elderly, with subjective dry mouth, were treated for 16‐day‐periods at random with: (i) Profylin fluoride gel with buffering components; (ii) Profylin fluoride gel without buffering components and (iii) rinsing with water. Applications were made four times a day and each period was followed by a 2‐week wash‐out period. The plaque pH was registered after a carbohydrate challenge and the following were recorded before and after each test period: stimulated salivary secretion rate, buffer capacity, number Colony Farming Units (CFU) mutans streptococci, lactobacilli and a sample of Candida albicans on oral mucosa. Results: Eleven participants (mean age 76.6 years) fulfilled the study. Changes in plaque pH measurements, when calculated as area under the curve (AUC6.2 and AUC5.7) values (pH × min), before and after each of the three treatments, showed no significant differences. A tendency to a higher plaque acidogenicity and amount of cariogenic microorganisms was found after the gel treatments. C. albicans was found in low levels. Conclusion: Frequent applications of the gel did not result in an improved neutralising effect in the elderly. This may be caused by a combination of several factors, such as the level of oral dryness of the individuals and low solubility, release and retention of the gel substances in plaque. Instead, an increased plaque acidogenicity was noted. 相似文献
20.
The most prevalent fungal infection of humans is candidiasis which is caused by species of Candida that are typical members of the commensal microbial flora of the oral mucosa and other body surfaces. Since species of Candida differ in virulence properties and susceptibilities to anti-fungal drugs, understanding the human commensal yeast flora will
have a significant impact on designing treatment and prevention strategies against yeast infections. However, although there
is a global interest in Candida species, the global distributions of Candida species remain largely unknown, especially among healthy hosts. Here we report the oral yeast flora from the surveys of over
1,000 medical students in China. Our results showed that this population had a yeast carriage rate (4.5%) much lower than
other population samples reported previously from Mainland China (40–70%). In addition, C. albicans was isolated at a much higher frequency than those from other Chinese samples, with a frequency (80.9%) more similar to those
in developed regions such as North America. The oral yeast carriage rates and yeast species compositions were similar between
male and female students and between the hosts borne and raised on Hainan Island and those borne and raised on Mainland China.
Furthermore, the sequence variation at the internal transcribed spacer (ITS) regions of the nuclear ribosomal RNA gene cluster
was analyzed for strains of the dominant species, C. albicans. Our analysis identified 14 ITS types among the 41 Hainan isolates of C. albicans. However, only four of the 14 ITS types were identical to those in reference strains from Europe and North America. Taken
together, our analyses suggest that the oral yeast flora among host populations in China is highly heterogeneous and that
there is a high ITS sequence diversity in the Hainan population of C. albicans. 相似文献