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1.
The purpose of this study was to evaluate specific effects of photodynamic inactivation (PDI) using methylene blue as photosensitizer and low-power laser irradiation on the viability of single-, dual-, and three-species biofilms formed by C. albicans, S. aureus, and S. mutans. Biofilms were grown in acrylic discs immersed in sterile brain heart infusion broth (BHI) containing 5% sucrose, inoculated with microbial suspension (106 cells/ml) and incubated for 5 days. On the fifth day, the effects of the methylene blue (MB) photosensitizer at a concentration of 0.1 mg/ml for 5 min and InGaAlP laser (660 nm) for 98 s, alone and conjugated were evaluated. Next, the discs were placed in tubes with sterile physiological solution [0.9% sodium chloride (NaCl)] and sonicated for to disperse the biofilms. Ten-fold serial dilutions were carried and aliquots seeded in selective agar, which were then incubated for 48 h. Then the numbers CFU/ml (log10) were counted and analyzed statistically (ANOVA, Tukey test, p < 0.05). Scanning electron microscopy (SEM) on discs treated with PDI and control biofilms groups was performed. Significant decreases in the viability of all microorganisms were observed for biofilms exposed to PDI mediated by MB dye. Reductions (log10) of single-species biofilms were greater (2.32–3.29) than the association of biofilms (1.00–2.44). Scanning electron microscopy micrographs suggested that lethal photosensitization occurred predominantly in the outermost layers of the biofilms. The results showed that PDI mediated by MB dye, might be a useful approach for the control of oral biofilms.  相似文献   

2.
Photodynamic inactivation (PDI) is a light-associated therapeutic approach suitable for treatment of local acute infections. The method is based on specific light-activated compound which by specific irradiation and in the presence of molecular oxygen produced molecular singlet oxygen and other reactive oxygen species, all toxic for pathogenic microbial cells. The study presents photodynamic impact of two recently synthesized water-soluble cationic lutetium (III) acetate phthalocyanines (LuPc-5 and LuPc-6) towards two pathogenic strains, namely, the Gram-negative bacterium Pseudomonas aeruginosa and a fungus Candida albicans. The photodynamic effect was evaluated for the cells in suspensions and organized in 48-h developed biofilms. The relatively high levels of uptakes of LuPc-5 and LuPc-6 were determined for fungal cells compared to bacterial cells. The penetration depths and distribution of both LuPcs into microbial biofilms were investigated by means of confocal fluorescence microscopy. The photoinactivation efficiency was studied for a wide concentration range (0.85–30 μM) of LuPc-5 and LuPc-6 at a light dose of 50 J cm?2 from red light-emitting diode (LED; 665 nm). The PDI study on microbial biofilms showed incomplete photoinactivation (<3 logs) for the used gentle drug-light protocol.  相似文献   

3.
The increase in survival and resistance of microorganisms organized in biofilms demonstrates the need for new studies to develop therapies able to break this barrier, such as photodynamic therapy, which is characterized as an alternative, effective, and non-invasive treatment. The objective was to evaluate in vitro the effect of antimicrobial photodynamic therapy on heterotypic biofilms of Candida albicans and Bacillus atrophaeus using rose bengal (12.5 μM) and light-emitting diode (LED) (532 nm and 16.2 J). We used standard strains of B. atrophaeus (ATCC 9372) and C. albicans (ATCC 18804). The biofilm was formed in the bottom of the plate for 48 h. For the photodynamic therapy (PDT) experimental groups, we added 100 μL of rose bengal with LED (P+L+), 100 μL of rose bengal without LED (P+L?), 100 μL of NaCl 0.9 % solution with LED (P?L+), and a control group without photosensitizer or LED (P?L?). The plates remained in agitation for 5 min (pre-irradiation) and were irradiated with LED for 3 min, and the biofilm was detached using an ultrasonic homogenizer for 30 s. Serial dilutions were plated in BHI agar and HiChrom agar and incubated at 37 °C/48 h. There was a reduction of 33.92 and 29.31 % of colony-forming units per milliliter (CFU/mL) for C. albicans and B. atrophaeus, respectively, from the control group to the group subjected to PDT. However, statistically significant differences were not observed among the P+L+, P+L?, P?L+, and P?L? groups. These results suggest that antimicrobial photodynamic therapy using rose bengal (12.5 μM) with a pre-irradiation period of 5 min and LED for 3 min was not enough to cause a significant reduction in the heterotypic biofilms of C. albicans and B. atrophaeus.  相似文献   

4.
The purpose of this study was to evaluate the effectiveness of anti-microbial photodynamic therapy (aPDT) mediated by curcumin (Cur) associated with LED light against biofilms of Candida dubliniensis, and further, investigate cellular uptake and drug penetration through the biofilms under confocal laser scanning microscopy (CLSM). Four C. dubliniensis strains were tested: three clinical isolates from HIV-positive patients and one reference strain (CBS 7987). Biofilms were treated with three Cur concentrations (20.0, 30.0, and 40.0 μM). All samples were incubated in the dark for 20 min and exposed to a 5.28 J/cm2 of LED light fluence. Additional samples of each strain were treated either with Cur or LED light only. Control samples had neither Cur nor light. After aPDT, results were read using the XTT salt reduction method. The data were statistically analyzed by two-way ANOVA followed by Games-Howell post-hoc test (α?=?0.05). Confocal laser scanning microscopy was used to verify both the uptake of Cur by yeast cells and its penetration through the biofilm. The results showed that aPDT promoted significant reduction on the metabolism of the biofilm-organized cells of C. dubliniensis. Further, while Cur was rapidly taken up by C. dubliniensis cells, a longer time interval was required to allow Cur penetration into biofilm cells. Based on these results, aPDT associating LED and Cur presents promising potential on fungal control of biofilms of C. dubliniensis.  相似文献   

5.
This study has evaluated the effects of photodynamic inactivation (PDI) using erythrosine as photosensitizer and green light-emitting diode (LED) on biofilms of Candida albicans alone and in combination with Enterococcus faecalis and Streptococcus mutans. We have also evaluated the effect of sucrose on biofilm formation and bacterial growth and sensitivity to PDI. Biofilms were formed in suspension of 106 cells/ml on plates before being grown in broth culture with and without sucrose and incubated for 48 h. Next, the treatment was applied using erythrosine at a concentration of 400 μM for 5 min and green LED (532 ± 10 nm) for 3 min on biofilms alone and in combination. The plates were washed and sonicated to disperse the biofilms, and serial dilutions were carried and aliquots seeded in Sabouraud agar before incubation for 48 h. Next, the colony-forming units per milliliter (CFU/ml; log10) were counted and analyzed statistically (ANOVA, Tukey test, P ≤ 0.05). Results show that S. mutans favors the growth of C. albicans in biofilms with sucrose, with treatment not being effective. However, when the biofilm was grown without sucrose, we found a reduction in biofilm formation and a significant decrease in the PDI treatment (P < 0.0001). In conclusion, both growth and sensitivity to PDI in biofilms of C. albicans are strongly influenced by bacterial combination, and the presence of sucrose affected directly the growth and sensitivity of the biofilm to PDI as sucrose is the substrate for construction of the exopolysaccharide matrix.  相似文献   

6.
We report the case of a 48-year-old man with a pseudocyst infected by Candida albicans, and review the relevant literature. The patient was successfully treated by a Roux-en-Y cystojejunostomy of the pseudocyst and adjunctive therapy with amphotericin B. Candida species isolated from a pancreatic pseudocyst or abscess should be considered pathogenic, and treated aggressively.  相似文献   

7.
This study evaluated the effects of antimicrobial photodynamic therapy (aPDT) mediated by Photodithazine® (PDZ) and LED light on the virulence factors of fluconazole-susceptible (CaS) and fluconazole-resistant (CaR) Candida albicans. Standardized suspensions of strains were prepared (107), and after 48 h of biofilm formation, these strains were incubated with PDZ (100 mg/L) for 20 min and exposed to LED light (660 nm, 37.5 J/cm2). Additional samples were treated with PDZ or light only, and the control consisted of biofilms that received no treatment. After aPDT, the cells were recovered and the virulence factors were evaluated. To analyze the capacity of adhesion, cells were recovered after aPDT and submitted to the adhesion process in the bottom of a 96-well plate. After this, metabolic activity tests (XTT assay) and cell viability (colony forming units per milliliter, CFU/mL) were applied. To evaluate the biofilm-forming ability after aPDT, the cells recovered were submitted to biofilm formation procedures, and the biofilm formed was evaluated by XTT, CFU/mL, and total biomass (crystal violet) tests. Lastly, the capacity for synthesizing protease and phospholipase enzymes after aPDT was evaluated by fluorimetric tests. Data were analyzed by two- or three-way ANOVA tests (p?≤?0.05). It was verified that aPDT reduced the viability of both strains, fluconazole-susceptible and fluconazole-resistant C. albicans. It was also observed that the CaR strain had lower susceptibility to the aPDT when compared with the CaS strain. However, regarding the virulence factors evaluated, it was demonstrated that aPDT did not alter the adherence and biofilm formation ability and enzymatic production.  相似文献   

8.
Photodynamic inactivation (PDI) has been used to inactivate microorganisms through the use of photosensitizers and visible light. On the one hand, near-infrared treatment (NIRT) has also bactericidal and dispersal effects on biofilms. In addition, dispersal biological tools such as enzymes have also been employed in antibiotic combination treatments. The aim of this work was to use alternative approaches to increase the PDI efficacy, employing combination therapies aimed at the partial disruption of the biofilms, thus potentially increasing photosensitizer or oxygen penetration and interaction with bacteria. To that end, we applied toluidine blue (TB)-PDI treatment to Staphylococcus aureus biofilms previously treated with NIRT or enzymes and investigated the outcome of the combined therapies. TB employed at 0.5 mM induced per se 2-log drop in S. aureus RN6390 biofilm viability. Each NIRT (980-nm laser) and PDI (635-nm laser) treatment induced a further reduction of 1-log of viable counts. The combination of successive 980- and 635-nm laser treatments on TB-treated biofilms induced additive effects, leading to a 4.5-log viable count decrease. Proteinase K treatment applied to S. aureus of the Newman strain induced an additive effect on PDI mortality, leading to an overall 4-log decrease in S. aureus viability. Confocal scanning laser microscopy after biofilm staining with a fluorescent viability test and scanning electron microscopy observations were correlated with colony counts. The NIRT dose employed (227 J/cm2) led to an increase from 21 to 47 °C in the buffer temperature of the biofilm system, and this NIRT dose also induced 100% keratinocyte death. Further work is needed to establish conditions under which biofilm dispersal occurs at lower NIRT doses.  相似文献   

9.

Background

Several recent studies in patients with idiopathic membranous nephropathy (iMN) from Western and Asian counties showed that some single nucleotide polymorphisms (SNPs) within the PLA2R1 and HLA-DQA1 genes are significantly associated with iMN. However, there is only 1 report on analysis of PLA2R1 and HLA regions in Japanese patients with iMN.

Methods

A total of 58 patients with iMN, 26 patients with secondary MN (sMN), and 50 patients with other diseases were enrolled. All patients were Japanese. We selected 6 SNPs within PLA2R1 and 1 SNP within HLA-DQA1, which were significantly associated with iMN in reported white European cohorts, and sequenced these exons using genomic DNA prepared from peripheral mononuclear cells from each patient. We then analyzed differences in PLA2R1 and HLA-DQA1 sequence variants among the 3 groups.

Results

Genotypic and allelic frequency distributions for 3 out of 6 SNPs within PLA2R1, rs3749117, rs35771982, and rs2715918 were significantly different between the iMN and control groups. Allelic frequency distributions for SNP rs2187668 within HLA-DQA1 were significantly different between the iMN and control groups. There were no correlations between PLA2R1 and HLA-DQA1 sequence variants and clinical parameters in patients with iMN. There were no significant differences in genotypic or allelic frequency distributions for examined SNPs between the sMN and control groups.

Conclusions

There are some differences in PLA2R1 SNP distributions between previously reported cohorts from other countries and our Japanese cohort of patients with iMN, while there is a significant association between SNP rs35771982 and iMN in most of reported cohorts.
  相似文献   

10.
11.
Although several genetic causes of steroid-resistant nephrotic syndrome (SRNS) have been identified, occurrence of these genetic abnormalities appears to be influenced by race. Seventy Korean children (39 girls, 31 boys) with SRNS underwent analysis for mutations of WT1 and NPHS2. Although NPHS2 mutations were not present in any of the patients, two different intronic mutations of WT1, IVS9+4 C>T and IVS9+5 G>A, were detected in four patients (three girls, one boy). Among the four patients with mutation, two girls with a karyotype of 46,XY had complete XY gonadal dysgenesis, one girl with a karyotype of 46,XX had normal genitalia, and one boy with a karyotype of 46,XY had hypospadia. A kidney biopsy conducted in three of the four patients revealed focal segmental glomerulosclerosis. The incidence of WT1 mutations observed in this study was similar to that of previous reports. However, the incidence of NPHS2 mutations seems to be very rare in Korean children. Genetic diagnosis of WT1 mutations should be recommended for children with SRNS, especially in cases involving a female phenotype or males with genital anomalies.  相似文献   

12.
13.
Liou TH  Chen HH  Wang W  Wu SF  Lee YC  Yang WS  Lee WJ 《Obesity surgery》2011,21(11):1758-1765

Background  

Significant variability in weight loss and glycemic control has been observed in obese patients receiving bariatric surgery. Genetic factors may play a role in the different outcomes.  相似文献   

14.
15.
Experimental studies have shown that homeobox genes are essential for the development of the kidney and urinary tract. Hoxa11/Hoxd11 double mutant mice demonstrate renal agenesis or hypoplasia. Since, to our knowledge, these genes have never been examined for alterations in humans with congenital anomalies of the kidney and urinary tract (CAKUT), we investigated whether mutations of HOXA11/HOXD11 genes are associated with non-syndromal congenital renal parenchymal malformations. DNA samples from 26 unrelated children with unilateral renal agenesis (URA), 20 with renal hypodysplasia (RHD) and 13 with multicystic dysplastic kidney (MCDK) were included in the study. Exons 1 and 2 of the HOXA11/HOXD11 genes were amplified individually by polymerase chain reaction (PCR) using 12 unique oligonucleotide primers. Single-strand conformation polymorphism (SSCP) analysis of overlapping polymerase chain reaction products was performed. SSCP analysis revealed no variant band shifts in the samples of the amplified segments of the 59 patients, suggesting lack of either mutation or polymorphisms. Our findings do not support the hypothesis that mutations in the HOXA11/HOXD11 coding regions are involved in the pathogenesis of human non-syndromal congenital renal parenchymal malformations. Further studies are necessary, since other genes known to affect nephrogenesis, as well as genetic and environmental factors, may be involved.  相似文献   

16.
Idiopathic nephrotic syndrome is a common pediatric kidney disease, 80% of all cases are steroid sensitive (SSNS). A significant proportion of children with SSNS will have a frequently relapsing or steroid-dependent course (FRNS/SDNS) that is associated with significant treatment-related morbidity. Mutations in NPHS2 account for more than 28% of all cases of steroid-resistant nephrotic syndrome (SRNS) and dominant mutations in WT1 for 5%; while mutations are absent from children with uncomplicated SSNS. Since FRNS/SDNS is phenotypically positioned within a spectrum between SSNS and SRNS, we hypothesized that heterozygous mutations of NPHS2 may be causing FRNS/SDNS. Mutational analysis of NPHS2 and WT1 was carried out in a single-center cohort of 20 children with FRNS/SDNS, ten children with uncomplicated SSNS (control), and 22 children with SRNS (control). Renal biopsy findings were available in 15/20 children with FRNS/SDNS and revealed IgM nephropathy, MCNS, and FSGS in six, five, and four children, respectively. Children with FRNS/SDNS were significantly younger at first presentation than those with SSNS and SRNS (median age: 3.0 years in FRNS/SDNS patients, 7.0 years in SSNS patients, and 5.0 in SRNS patients; p < 0.001). No NPHS2 or WT1 mutations were found in patients with FRNS/SDNS and uncomplicated SSNS. The hypothesis that FRNS/SDNS may be associated with heterozygous mutations in NPHS2 or WT1 was not confirmed.  相似文献   

17.
Familial clustering of vesico-ureteral reflux (VUR) suggests that genetic factors play an important role in the pathogenesis of this condition. The SLIT2 protein and its receptor, ROBO2, have key functions in the formation of the ureteric bud. Two recent studies have found that ROBO2 gene missense mutations are associated with VUR. In the study reported here, we investigated the genetic contribution of the SLIT2 and ROBO2 genes in non-syndromic familial VUR by mutation screening of 54 unrelated patients with primary VUR. Direct sequencing of all 26 exons and the exon–intron boundaries revealed six ROBO2 gene variants, two of which were new. Direct sequencing of all 37 exons and the exon–intron boundaries identified 20 SLIT2 gene variants, two of which were new. One variant, c.4253C > T, which was found in two families, leads to an amino acid substitution in a relatively well-conserved amino acid, p.Ala1418Val, which was predicted to cause an altered secondary structure but to have little impact on the three-dimensional structure. This missense variant did not segregate with VUR in these two families and was not found in 96 control subjects. We conclude that gene variants in ROBO2 and SLIT2 are rare causes of VUR in humans. Our results provide further evidence for the genetic heterogeneity of this disorder.  相似文献   

18.
The treatment of Klebsiella pneumoniae, particularly extended-spectrum β-lactamase (ESBL)-producing K. pneumoniae, is currently a great challenge. Photodynamic antimicrobial chemotherapy is a promising approach for killing antibiotic-resistant bacteria. The aim of this study was to evaluate the capacity of 5-aminolevulinic acid (5-ALA) and its derivative 5-ALA methyl ester (MAL) in the presence of white light to cause photodynamic inactivation (PDI) of K. pneumoniae planktonic and biofilm cells. In the presence of white light, 5-ALA and MAL inactivated planktonic cells in a concentration-dependent manner. Biofilms were also sensitive to 5-ALA and MAL-mediated PDI. The mechanisms by which 5-ALA and MAL caused PDI of ESBL-producing K. pneumonia were also investigated. Exposure of K. pneumonia to light in the presence of either 5-ALA or MAL induced cleavage of genomic DNA and the rapid release of intracellular biopolymers. Intensely denatured cytoplasmic contents and aggregated ribosomes were also detected by transmission electron microscopy. Scanning electron microscopy showed that PDI of biofilms caused aggregated bacteria to detach and that the bacterial cell envelope was damaged. This study provides insights into 5-ALA and MAL-mediated PDI of ESBL-producing K. pneumoniae.  相似文献   

19.

Background  

Pleomorphic carcinomas of the lung are uncommon malignant tumors composed of carcinomatous and sarcomatous components and are distinguished from other non-small-cell lung carcinomas by a more aggressive clinical course with early distant metastases and far worse survival. Epidermal growth factor receptor (EGFR) and p53 are common genes involved in the pathogenesis of non-small-cell lung carcinomas, but their roles in pleomorphic carcinomas are unclear. The potential clinical activity of EGFR-targeted therapy is also unknown.  相似文献   

20.
Primary steroid-resistant nephrotic syndrome (SRNS) is characterized by childhood onset of proteinuria and progression to end-stage renal disease. In 26% of cases it is caused by recessive mutations in NPHS2 (podocin). Congenital nephrotic syndrome (CNS) is caused by mutations in NPHS1 (nephrin) or NPHS2. In three families mutations in NPHS1 and NPHS2 had been reported to occur together, and these tri-allelic mutations were implicated in genotype/phenotype correlations. To further test the hypothesis of tri-allelism, we examined a group of 62 unrelated patients for NPHS1 mutations, who were previously shown to have NPHS2 mutations; 15 of 62 patients had CNS. In addition, 12 CNS patients without NPHS2 mutation were examined for NPHS1 mutations. Mutational analysis yielded three different groups. (1) In 48 patients with two recessive NPHS2 mutations (11 with CNS), no NPHS1 mutation was detected, except for 1 patient, who had one NPHS1 mutation only. This patient was indistinguishable clinically and did not have CNS. (2) In 14 patients with one NPHS2 mutation only (4 with CNS), we detected two additional recessive NPHS1 mutations in the 4 patients with CNS. They all carried the R229Q variant of NPHS2. The CNS phenotype may be sufficiently explained by the presence of two NPHS1 mutations. (3) In 12 patients without NPHS2 mutation (all with CNS), we detected two recessive NPHS1 mutations in 11 patients, explaining their CNS phenotype. We report ten novel mutations in the nephrin gene. Our data do not suggest any genotype/phenotype correlation in the 5 patients with mutations in both the NPHS1 and the NPHS2 genes.Members of the Study Group of the Arbeitsgemeinschaft für Pädiatrische Nephrologie (APN) participating in this study: J. Thaarup (Aalborg, Denmark); P. Henning (Adelaide, Australia); I. Attrach (Aleppo, Syria); A. Bakkaloglu (Ankara, Turkey); C. Rudin (Basel, Switzerland); R. Bogdanovic (Belgrade, Yugoslavia); S. Briese, J. Gellermann, T. Lennert, U. Querfeld, Sacherer, M. Schürmann, and M. Zimmering (Berlin, Germany); C. Roth, C. Schröter, and B. Utsch (Bonn, Germany); Matthes (Bremen, Germany); A. Heilmann and G. Kalvoda (Dresden, Germany); F. Wegner (Düren, Germany); V. Schumacher (Düsseldorf, Germany); Bär, B. Bosch, M. Kamm, S.M. Karle, K. Nüsken, C. Plank, W. Rascher, and B. Zimmermann (Erlangen, Germany); K. E. Bonzel, M. Bald, P. Hoyer, and U. Vester (Essen, Germany); U. Neyer (Feldkirch, Austria); Rippel (Frankfurt, Germany); M. Brandis, A. Fuchshuber, K. Häffner, A. Kirchhoff, and M. Pohl (Freiburg, Germany); J. Steiss (Giessen, Germany); J.P. Haas (Greifswald, Germany); L. Patzer (Halle, Germany); M. Kemper, H. Altrogge, D.E. Müller-Wiefel, U. Peters, and K. Timmermann (Hamburg, Germany); J.H.H. Ehrich, H. Haller, and C. Strehlau (Hannover, Germany); M. Daschner, S. Hessing, Janssen, D. Kiepe, S. Köpf, O. Mehls, and B. Tönshoff (Heidelberg, Germany); F. Prüfer and L.B. Zimmerhackl (Innsbruck, Austria); U. John, J. Misselwitz, G. Rönnefarth, and J. Seidel (Jena, Germany); D. Blowey and J. Scheinman (Kansas City, Mo., USA); B. Beck, K. Frankenbusch, B. Hoppe, C. Licht, D. Michalk, T. Ronda, and L. Stapenhorst (Cologne, Germany); D. Drozdz and A. Pogan (Krakau, Poland); Froster, E. Vogel and S. Wygoda (Leipzig, Germany); R. Hettenger (Los Angeles, Calif., USA); H. Schriewer and H.-P. Weber (Lüdenscheid, Germany); R. Beetz (Mainz, Germany); M. Konrad (Marburg, Germany); H. Fehrenbach (Memmingen, Germany); M. Griebel and B. Klare (München, Germany); M. Bulla, S. Fründ, E. Kuwertz-Bröking, A. Schulze-Everding and Yelbuz (Münster, Germany); L. Monnens (Nijmegen, The Netherlands); J. Janda and T. Seemann (Prag, Czech Republic); G. Adomssent, G. Krüger, Lorenzen, J. Muscheites, H.-J. Stolpe and M. Wigger (Rostock, Germany); W. Sperl (Salzburg, Austria); R. Egger (Schaffhausen, Switzerland); V. Tasic (Skopje, Macedonia); M. Bald and H.-E. Leichter (Stuttgart); O. Amon (Tübingen, Germany); T. Arbeiter, C. Aufricht and K. Müller (Vienna, Austria); D. Bockenhauer and N. Siegel (New Haven, Conn., USA); and T. Neuhaus and A. Staub (Zürich, Switzerland)  相似文献   

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