Synergism between fluconazole and methylene blue-photodynamic therapy against fluconazole-resistant Candida strains.

Photodynamic therapy (PDT) has been proved to be effective against fungi and it may be employed as a coadjutant to conventional antifungal agents, leading to a more effective microbial control minimising side effects. This work evaluates the combined effect of PDT and fluconazole against resistant Candida albicans, Candida glabrata and Candida krusei. The yeasts were submitted to methylene blue-PDT (MB-PDT) in sub-inhibitory concentrations. In the present work, MB-PDT combined with fluconazole was more efficient in the inhibition of the C. albicans and C. glabrata than each treatment alone, being possible to infer that the treatments are synergic.

Disinfection of corrugated tubing by ozone and ultrasound in mechanically ventilated tracheostomized patients.

BACKGROUND: Medical equipment coming into contact with non-intact skin or mucous membranes is classified as semi-critical material. This equipment requires at least high-level disinfection, as the major risk in all invasive procedures is the introduction of pathogenic microbes causing hospital-associated infections. AIM: To evaluate the capacity of ozone gas and ultrasound to disinfect semi-critical, thermally sensitive material. METHODS: Used corrugated tubing from mechanically ventilated tracheostomized patients in the intensive care unit was obtained. Enzymatic detergent was applied for 15min before different disinfection techniques were evaluated as follows: Group A (0.2% peracetic acid); Group B (ultrasound for 60min); Group C (application of ozone gas at a concentration of 33mg/L for 15min); Group D (ultrasound for 30min and ozone for 15min); Group E (ultrasound for 60min and ozone for 15min). FINDINGS: Application of ultrasound for 60min reduced the level of microbial contamination by 4 log10, whereas ozone alone and the other two combined techniques (ultrasound and ozone) and the peracetic acid reduced the level of microbial contamination by 5 log10. CONCLUSION: Ozone was the most advantageous technique taking into consideration processing time, ease of use, effectiveness, and cost. The use of ozone gas to disinfect semi-critical material proved to be technically feasible and extremely promising.

Mutational analysis of the genes encoding RFamide-related peptide-3, the human orthologue of gonadotrophin-inhibitory hormone, and its receptor (GPR147) in patients with gonadotrophin-releasing hormone-dependent pubertal disorders.

RFamide-related peptide-3 (RFRP-3), the orthologue of avian gonadotrophin-inhibitory hormone, and its receptor GPR147 have been recently identified in the human hypothalamus, and their roles in the regulation of reproductive axis has been studied. The present study aimed to investigate whether the presence of variants in the genes encoding human RFRP-3 (NPVF gene) and its receptor, GPR147 (NPFFR1 gene), is associated with the occurrence of gonadotrophin-releasing hormone-dependent pubertal disorders. Seventy-eight patients with idiopathic central precocious puberty (CPP) and 51 with normosmic isolated hypogonadotrophic hypogonadism (nIHH) were investigated. Fifty healthy subjects comprised the control group. The coding sequences of the NPVF and NPFFR1 genes were amplified and sequenced. Odds ratios (OR) were used to estimate the likelihood of CPP or nIHH in the presence of the described polymorphisms. All such polymorphisms have already been registered in the National Center for Biotechnology Information database. A three-nucleotide in frame deletion was identified in the NPVF gene (p.I71_K72), with a smaller proportion in the CPP (5%) compared to the nIHH (15%) group (P = 0.06). This results in the deletion of the isoleucine at position 71, adjacent to lysine at an endoproteolytic cleavage site of the precursor peptide. This polymorphism was associated with a lower risk of CPP (OR = 0.33; 95% confidence interval = 0.08-0.88); interestingly, only two men with nIHH were homozygotes for this variant. A total of five missense polymorphisms were found in the NPFFR1 gene, which encodes GPR147, with similar frequencies among groups and no association with pubertal timing. Our data suggest that RFRP-3/GPR147 may play secondary, modulatory roles on the regulation of pubertal development; a restraining modulatory effect of the NPVF p.I71_K72 variant on the activation of the gonadotrophic axis cannot be ruled out and deserves further investigation.

Evaluation of the agreement by examiners according to classifications of third molars.

OBJECTIVES: This study recorded and evaluated the intra- and inter-group agreement degree by different examiners for the classification of lower third molars according to both the Winter's and Pell & Gregory's systems. STUDY DESIGN: An observational and cross-sectional study was realized with forty lower third molars analyzed from twenty digital panoramic radiographs. Four examiner groups (undergraduates, maxillofacial surgeons, oral radiologists and clinical dentists) from Aracaju, Sergipe, Brazil, classified them in relation to angulation, class and position. The variance test (ANOVA) was applied in the examiner findings with significance level of p<0.05 and confidence intervals of 95%. RESULTS: Intra- and inter-group agreement was observed in Winter's classification system among all examiners. Pell & Gregory's classification system showed an average intra-group agreement and a statistical significant difference to position variable in inter-group analysis with greater disagreement to the clinical dentists group (p<0.05). CONCLUSIONS: High reproducibility was associated to Winter's classification, whereas the system proposed by Pell & Gregory did not demonstrate appropriate levels of reliability.

Biosurfactant production by Pseudomonas aeruginosa grown in residual soybean oil.

Pseudomonas aeruginosa PACL strain, isolated from oil-contaminated soil taken from a lagoon, was used to investigate the efficiency and magnitude of biosurfactant production, using different waste frying soybean oils, by submerged fermentation in stirred tank reactors of 6 and 10 l capacities. A complete factorial experimental design was used, with the goal of optimizing the aeration rate (0.5, 1.0, and 1.5 vvm) and agitation speed (300, 550, and 800 rpm). Aeration was identified as the primary variable affecting the process, with a maximum rhamnose concentration occurring at an aeration rate of 0.5 vvm. At optimum levels, a maximum rhamnose concentration of 3.3 g/l, an emulsification index of 100%, and a minimum surface tension of 26.0 dynes/cm were achieved. Under these conditions, the biosurfactant production derived from using a mixture of waste frying soybean oil (WFSO) as a carbon source was compared to production when non-used soybean oil (NUSO), or waste soybean oils used to fry specific foods, were used. NUSO produced the highest level of rhamnolipids, although the waste soybean oils also resulted in biosurfactant production of 75-90% of the maximum value. Under ideal conditions, the kinetic behavior and the modeling of the rhamnose production, nutrient consumption, and cellular growth were established. The resulting model predicted data points that corresponded well to the empirical information.

Enhancement of rhamnoplipid production in residual soybean oil by an isolated strain of Pseudomonas aeruginosa.

In the present work, the production of rhamnolipid from residual soybean oil (RSO) from food frying facilities was studied using a strain of Pseudomonas aeruginosa of contaminated lagoon, isolated from a hydrocarbon contaminated soil. The optimization of RSO, ammonium nitrate, and brewery residual yeast concentrations was accomplished by a central composite experimental design and surface response analysis. The experiments were performed in 500-mL Erlenmeyer flasks containing 50 mL of mineral medium, at 170 rpm and 30 +/- 1 degrees C, for a 48-h fermentation period. Rhamnolipid production has been monitored by measurements of surface tension, rhamnose concentration, and emulsifying activity. The best-planned results, located on the central point, have corresponded to 22 g/L of RSO, 5.625 g/L of NH(4)NO(3), and 11.5 g/L of brewery yeast. At the maximum point the values for rhamnose and emulsifying index were 2.2 g/L and 100%, respectively.

Side-viewing fiberoptic catheter for biospectroscopy applications.

Utilization of fiberoptic catheters can turn the Raman and fluorescence spectroscopy systems into powerful bio-medical diagnostic probes. An in vivo bio-chemical diagnosis of some important organs like the esophagus, intestine, lung branches, artery, etc., can be possible by developing fiber-probes with good signal collection capabilities, a good flexibility to scan different spatial regions of the sample and less background signals generated in the probes themselves. An in vivo diagnosis of endoluminal inner walls utilizing front-viewing catheters (FVC) is very difficult because the internal diameter of these organs do not allow (excitation and collection) flexibility to access the different spatial regions of the sample. In this work we have developed, different side-viewing catheter (SVC) probes with a very small distal tip (semi sphere, phi approximately 1.5 mm) and micro mirrors allow beam steering of the excitation and collected radiation at a 90 degree angle. Preliminary results of spectroscopic applications have been presented. Reflectance, fluorescence and Raman scattering measurements have been used to compare the efficiency of SVC with traditional FVC probes. The results demonstrate that the SVC probes not only exhibit more flexibility but also similar spectral characteristics and signal collection efficiencies in comparison with conventional FVC probes.

Development of catheters with low fiber background signals for Raman spectroscopic diagnosis applications.

Utilization of optical-fiber catheters can turn the Raman spectroscopy system into a powerful remote biomedical diagnostic probe. An in vivo (a qualitative and a quantitative) biochemical diagnosis of biotissues is possible by developing the Raman-fiber probes with a good flexibility and less background signals generated in the probes themselves. Considering the isotropic nature of Raman scattering, the amount of Raman signal guided through the fiber is expected to depend on the numerical aperture (NA) of the fiber. To study the dependence for catheter probes experimentally, various flexible probes (with small diameter fibers) with different combinations of numerical apertures and with different assembling materials (biocompatible) have been developed. The catheter probes have been characterized by collecting the near infrared excited Raman scattered light from cholesterol powder. The results demonstrate that the catheters with a combination of lower NA (0.12) fibers used for laser excitation and relatively higher NA (0.22) fibers for Raman signal collection will have lower background signals generated in the probes. Furthermore, the catheters with a black Teflon tubing cover and black epoxy resin adhesives were found to give better results.

Two-wave mixing in photorefractive Bi(12)SiO(20) fibers.

We present what is to our knowledge the first experimental observation of the energy-exchange effect between two coherent beams in Bi(12)SiO(20) single-crystal optical fiber grown by the laser-heated pedestal growth technique.