Evaluation of Environmental Mycobacteria Contamination in a Specific Pathogen Free Animal Facility from a Tropical Country

P>With the evidence showing the protection variability of bacille Calmette-Guerin, new potential vaccines for tuberculosis have been tested around the world. One of the general concerns in tuberculosis vaccine development is the possibility of priming the host immune system with prior exposure to environmental mycobacteria antigens, which can change the efficacy of subsequent vaccination. As there is a great homology between the species from Mycobacterium genera, the previous contact of experimental animals with environmental mycobacteria could sensitize the mice and, in this way, could influence subsequent vaccine research. The aim of our study was to investigate critical points in an animal facility to search for environmental mycobacteria that eventually could be in direct or indirect contact with the experimental animals. Samples were collected from surfaces of walls, floor, animal cages and shelves and analysed using the Ogawa-Kudoh decontamination method. Samples of drinking water, food and sawdust were collected for analysis by the NALC/NaOH decontamination method. Also, the samples were cultivated directly in broth medium, without any method for decontamination. After decontamination methods, we observed bacterial colony growth in 4.31% of the total of samples analysed. These samples were stained with Ziehl-Neelsen and we did not detect any acid-fast bacilli, suggesting that the animal facility analysed is free from contamination by environmental mycobacteria and is not a source of mycobacterial antigens. Furthermore, our study showed a new paradigm in tuberculosis vaccine development: concern about the animal facility environment in terms of immune system priming of experimental animals by nascent bacterial contaminants.

Systemic Model for Diagnosis of the Micro, Small and Medium Enterprises from Two Cities from the Countryside of the State of So Paulo in Brazil

This article presents a proposal of a systemic model composed for the micro and small companies (MSE) of the region of Ribeiro Preto and the agents which influenced their environment. The proposed model was based on Stafford Beer`s (Diagnosing the system for organizations. Chichester, Wiley, 1985) systemic methodologies VSM (Viable System Model) and on Werner Ulrich`s (1983) CSH (Critical Systems Heuristics). The VSM is a model for the diagnosis of the structure of an organization and of its flows of information through the application of the cybernetics concepts (Narvarte, In El Modelo del Sistema Viable-MSV: experiencias de su aplicacin en Chile. Proyecto Cerebro Colectivo del IAS, Santiago, 2001). On the other hand, CSH focus on the context of the social group applied to the systemic vision as a counterpoint to the organizational management view considered by the VSM. MSE of Ribeiro Preto and Sertozinho had been analyzed as organizations inserted in systems that relate and integrate with other systems concerning the public administration, entities of representation and promotion agencies. The research questions: which are the bonds of interaction among the subsystems in this process and who are the agents involved? The systemic approach not only diagnosed a social group, formed by MSE of Ribeiro Preto and Sertozinho, public authorities and support entities, but could also delineate answers that aimed the clarification of obscure questions generating financial assistance to the formularization of efficient actions for the development of this system.

Thoracic vibrations in stingless bees (Melipona seminigra): resonances of the thorax influence vibrations associated with flight but not those associated with sound production

Bees generate thoracic vibrations with their indirect flight muscles in various behavioural contexts. The main frequency component of non-flight vibrations, during which the wings are usually folded over the abdomen, is higher than that of thoracic vibrations that drive the wing movements for flight. So far, this has been concluded from an increase in natural frequency of the oscillating system in association with the wing adduction. In the present study, we measured the thoracic oscillations in stingless bees during stationary flight and during two types of non-flight behaviour, annoyance buzzing and forager communication, using laser vibrometry. As expected, the flight vibrations met all tested assumptions for resonant oscillations: slow build-up and decay of amplitude; increased frequency following reduction of the inertial load; and decreased frequency following an increase of the mass of the oscillating system. Resonances, however, do not play a significant role in the generation of non-flight vibrations. The strong decrease in main frequency at the end of the pulses indicates that these were driven at a frequency higher than the natural frequency of the system. Despite significant differences regarding the main frequency components and their oscillation amplitudes, the mechanism of generation is apparently similar in annoyance buzzing and forager vibrations. Both types of non-flight vibration induced oscillations of the wings and the legs in a similar way. Since these body parts transform thoracic oscillations into airborne sounds and substrate vibrations, annoyance buzzing can also be used to study mechanisms of signal generation and transmission potentially relevant in forager communication under controlled conditions.

Pressure-Frequency Sensing Subxiphoid Access System for Use in Percutaneous Cardiac Electrophysiology: Prototype Design and Pilot Study Results

We have designed, built, and tested an early prototype of a novel subxiphoid access system intended to facilitate epicardial electrophysiology, but with possible applications elsewhere in the body. The present version of the system consists of a commercially available insertion needle, a miniature pressure sensor and interconnect tubing, read-out electronics to monitor the pressures measured during the access procedure, and a host computer with user-interface software. The nominal resolution of the system is <0.1 mmHg, and it has deviations from linearity of <1%. During a pilot series of human clinical studies with this system, as well as in an auxiliary study done with an independent method, we observed that the pericardial space contained pressure-frequency components related to both the heart rate and respiratory rate, while the thorax contained components related only to the respiratory rate, a previously unobserved finding that could facilitate access to the pericardial space. We present and discuss the design principles, details of construction, and performance characteristics of this system.

(1)H magnetic resonance spectroscopy imaging of the hippocampus in patients with panic disorder

Recent theories of panic disorder propose an extensive involvement of limbic system structures, such as the hippocampus, in the pathophysiology of this condition. Despite this, no prior study has examined exclusively the hippocampal neurochemistry in this disorder. The current study used proton magnetic resonance spectroscopy imaging ((1)H-MRSI) to examine possible abnormalities in the hippocampus in panic disorder patients. Participants comprised 25 panic patients and 18 psychiatrically healthy controls. N-acetylaspartate (NAA, a putative marker of neuronal viability) and choline (Cho, involved in the synthesis and degradation of cell membranes) levels were quantified relative to creatine (Cr, which is thought to be relatively stable among individuals and in different metabolic condition) in both right and left hippocampi. Compared with controls, panic patients demonstrated significantly lower NAA/Cr in the left hippocampus. No other difference was detected. This result is consistent with previous neuroimaging findings of hippocampal alterations in panic and provides the first neurochemical evidence suggestive of involvement of this structure in the disorder. Moreover, lower left hippocampal NAA/Cr in panic disorder may possibly reflect neuronal loss and/or neuronal metabolic dysfunction, and could be related to a deficit in evaluating ambiguous cues. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Oral tolerance attenuates airway inflammation and remodeling in a model of chronic pulmonary allergic inflammation

We investigated the effects of oral tolerance (OT) in controlling inflammatory response, hyperresponsiveness and airway remodeling in guinea pigs (GP) with chronic allergic inflammation. Animals received seven inhalations of ovalbumin (1-5 mg/mL-OVA group) or normal saline (NS group). OT was induced by offering ad libitum ovalbumin 2% in sterile drinking water starting with the 1st ovalbumin inhalation (OT1 group) or after the 4th (OT2 group). The induction of OT in sensitized animals decreased the elastance of respiratory system (Ers) response after both antigen and methacholine challenges, peribronchial edema formation, eosinophilic airway infiltration, eosinophilopoiesis, and airways collagen and elastic fiber content compared to OVA group (P < 0.05). The number of mononuclear cells and resistance of respiratory system (Rrs) responses after antigen and methacholine challenges were decreased only in OT2 group compared to OVA group (P < 0.05). Concluding, our results show that inducing OT attenuates airway remodeling as well as eosinophilic inflammation and respiratory system mechanics. (C) 2008 Elsevier B.V. All rights reserved.

NEW COUPLING SYSTEM FOR INTERFERENCE SCREWS: BIOMECHANICAL RESISTANCE TO TORSION

Objective: To introduce a new coupling system between screw driver and interference screw, and biomechanical tests that validate the safety of its application. Methods: The new system was submitted to biomechanical torsion assays. Two types of analysis were performed: maximum torque of manual insertion of the screws into bovine bone; destructive assays of torsion of the system using an INSTRON 55MT machine. The same tests were also performed on a control group, using a commercially available interference screw coupling system (Acufex (R)). Results: In the tests on manual insertion of screws in bovine femurs, the average values found with a digital torque meter were 1.958 N/m for Acufex (R) and 2.563 N/m for FMRP. Considering p>0.05, there were no statistical differences between the two groups (p=0.02) in the values for maximum torque of insertion, in the two systems studied. The average values for maximum torque of torsion resisted by the screw were 15N/m for the Acufex (R) screw and 13N/m for the FMRP screw, again with no statistical differences between the two groups (p>0.05). In the evaluation of angular deformation, there was also no significant difference between the two screw types (p=0.15). Conclusion: The new coupling system for interference screws developed at FMRP-USP revealed a torsion resistance that is comparable with the system already available on the market and regulated for international use.

Development of microemulsions to topically deliver 5-aminolevulinic acid in photodynamic therapy

The aim of this study was to obtain and to characterize microemulsions containing 5-aminolevulinic acid (5-ALA) and to investigate the influence of these systems in drug skin permeation for further topical photodynamic therapy (PDT). 5-ALA was incorporated in water-in-oil (W/O), bicontinuous (Bc), and oil-in-water (O/W) microemulsions obtained by the titration of ethyl oleate and PEG-8 caprylic/capric glycerides:polyglyceryl-6 dioleate (3:1) mixtures with water. Selected systems were characterized by conductivity, viscosity, size of the droplets, and drug release. The stability of the drug in the microemulsions was also assessed. Moreover, the in vitro and in vivo skin permeation of 5-ALA was investigated using diffusion cells and confocal scanning laser microscopy (CSLM), respectively. Despite the fact that the O/W microemulsion decreased the 5-ALA diffusion coefficient and retarded the drug release, it also significantly increased the in vitro drug skin permeation when compared to other 5-ALA carriers. It was observed by CSLM that the red fluorescence of the skin increased homogeneously in the deeper skin layers when the 5-ALA microemulsion was applied in vivo, probably due to the formation of the photoactive protoporphyrin IX. The microemulsion developed carried 5-ALA to the deeper skin layers, increasing the red fluorescence of the skin and indicating the potentiality of the system for topical 5-ALA-PDT. (C) 2010 Elsevier B.V. All rights reserved.

Detrimental role of endogenous nitric oxide in host defence against Sporothrix schenckii

We earlier demonstrated that nitric oxide (NO) is a fungicidal molecule against Sporothrix schenckii in vitro. In the present study we used mice deficient in inducible nitric oxide synthase (iNOS(-/-)) and C57BL/6 wild-type (WT) mice treated with N omega-nitro-arginine (Nitro-Arg-treated mice), an NOS inhibitor, both defective in the production of reactive nitrogen intermediates, to investigate the role of endogenous NO during systemic sporotrichosis. When inoculated with yeast cells of S. schenckii, WT mice presented T-cell suppression and high tissue fungal dissemination, succumbing to infection. Furthermore, susceptibility of mice seems to be related to apoptosis and high interleukin-10 and tumour necrosis factor-alpha production by spleen cells. In addition, fungicidal activity and NO production by interferon-gamma (IFN-gamma) and lipopolysaccharide-activated macrophages from WT mice were abolished after fungal infection. Strikingly, iNOS(-/-) and Nitro-Arg-treated mice presented fungal resistance, controlling fungal load in tissues and restoring T-cell activity, as well as producing high amounts of IFN-gamma Interestingly, macrophages from these groups of mice presented fungicidal activity after in vitro stimulation with higher doses of IFN-gamma. Herein, these results suggest that although NO was an essential mediator to the in vitro killing of S. schenckii by macrophages, the activation of NO system in vivo contributes to the immunosuppression and cytokine balance during early phases of infection with S. schenckii.

FACILITATION OF ENDOCANNABINOID EFFECTS IN THE VENTRAL HIPPOCAMPUS MODULATES ANXIETY-LIKE BEHAVIORS DEPENDING ON PREVIOUS STRESS EXPERIENCE

Although several pieces of evidence indicate that the endocannabinoid system modulates anxiety-like behaviors and stress adaptation, few studies have investigated the brain sites of these effects. The ventral hippocampus (VHC) has been related to anxiety behaviors and has a high expression of cannabinoid-1 (CBI) receptors. Moreover, endocannabinoid signaling in the hippocampus is proposed to regulate stress adaptation. In the present study we investigated the role of previous stressful experience on the effects of AM404, an anandamide uptake inhibitor, microinjected into the VHC of rats submitted to the elevated plus maze (EPM), a widely used animal model of anxiety. Stressed animals were forced restrained for two h 24 h before the test. AM404 (5-50 pmol) microinjection promoted an anxiogenic-like effect in non-stressed rats but decreased anxiety in stressed animals. AM251 (0.01 to 1000 pmol), a CBI receptor antagonist, failed to change behavior in the EPM over a wide dose range but prevented the effects of AM404. Anxiolytic-like effects of AM404 (5 pmol) intra-VHC injection were also observed in the Vogel conflict test (VCT), another model of anxiety that involves previous exposure to stressful situations (48 h of water deprivation). These results suggest that facilitation of endocannabinoid system neurotransmission in the ventral hippocampus modulates anxiety-like behaviors and that this effect depends on previous stress experience. (C) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

Plant-antivenom: Database of anti-venom medicinal plants

Plant-antivenom is a computational Websystem about medicinal plants with anti-venom properties. The system consists of a database of these plants, including scientific publications on this subject and amino acid sequences of active principles from venomous animals. The system relates these data allowing their integration through different search applications. For the development of the system, the first surveys were conducted in scientific literature, allowing the creation of a publication database in a library for reading and user interaction. Then, classes of categories were created, allowing the use of tags and the organization of content. This database on medicinal plants has information such as family, species, isolated compounds, activity, inhibited animal venoms, among others. Provision is made for submission of new information by registered users, by the use of wiki tools. Content submitted is released in accordance to permission rules defined by the system. The database on biological venom protein amino acid sequences was structured from the essential information from National Center for Biotechnology Information (NCBI). Plant-antivenom`s interface is simple, contributing to a fast and functional access to the system and the integration of different data registered on it. Plant-antivenom system is available on the Internet at http://gbi.fmrp.usp.br/plantantivenom.

Antioxidant enzymatic defense in salivary glands of streptozotocin-induced diabetic rats: a temporal study

Hyperglycemia induces overproduction of superoxide and it is related to diabetic complications. In this study, we analyzed the antioxidant enzymatic defense and the lipid peroxidation of rat salivary glands in six different periods of diabetic condition. Ninety-six rats were divided into 12 groups: C7/14/21128/45/60 (non-diabetic animals) and D7/14/21/28/45/60 (diabetic animals). Diabetes was induced by streptozotocin and the rats were euthanized after 7, 14, 21, 28, 45, or 60 days. Their parotid (PA) and submandibular (SM) glands were removed soon after the sacrifice and the total protein and malondialdehyde (MDA) concentrations, as well as, the superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activities were determined. Twenty-one days after the diabetes induction, the SM glands showed an increase in SOD, CAT, and GPx activities, as well as, MDA concentration. Concerning the PA glands, an increase in the CAT activity and MDA content was observed throughout the observation period. The results suggest that diabetes can cause alterations on the salivary glands and that PA and SM glands react differently when exposed to diabetes condition. However, no impairment of antioxidant system was observed in the group whose diabetic condition had been induced 60 days earlier, herein named 60-day group. Copyright (C) 2010 John Wiley & Sons, Ltd.

Effect of Conventional and Resin-modified Glass-Ionomer Liner on Dentin Adhesive Interface of Class I Cavity Walls After Thermocycling

Objective: The aim of this in vitro study was to analyze the effect of glass-ionomer cement as a liner on the dentin/resin adhesive interface of lateral walls of occlusal restorations after thermocycling. Materials and Methods: Occlusal cavities were prepared in 60 human molars, divided into six groups: no liner (1 and 4); glass-ionomer cement (GIC, Ketac Molar Easymix, 3M ESPE) (2 and 5); and resin-modified glass-ionomer cement (RMGIC, Vitrebond, 3M ESPE) (3 and 6). Resin composite (Filtek Z250, 3M ESPE) was placed after application of an adhesive system (Adper Single Bond 2, 3M ESPE) that was mixed with a fluorescent reagent (Rhodamine B) to allow confocal microscopy analysis. Specimens of groups 4, 5 and 6 were thermocycled (5 degrees C-55 degrees C) with a dwell time of 30 seconds for 5000 cycles. After this period, teeth were sectioned in approximately 0.8-mm slices. One slice of each tooth was randomly selected for confocal microscopy analysis. The other slices were sectioned into 0.8 nun x 0.8 mm beams, which were submitted to microtensile testing (MPa). Data were analyzed using two-way ANOVA and Tukey test (p < 0.05). Results: There was no detectedstatistical difference on bond strength among groups (alpha < 0.05). Confocal microscopy analysis showed a higher mean gap size in group 4(12.5 mu m) and a higher percentage of marginal gaps in the thermocycled groups. The RNIGIC liner groups showed the lowest percentage of marginal gaps. Conclusions: Lining with RMGIC resulted in less gap formation at the dentin/resin adhesive interface after artificial aging. RMGIC or GIC liners did not alter the microtensile bond strength of adhesive system/resin composite to dentin on the lateral walls of Class I restorations.

Bond Strength of Epiphany Sealer Prepared with Resinous Solvent

This study evaluated in vitro the bond strength of Epiphany sealer prepared with resinous solvent of Epiphany system (Thinning resin) by using a push-out test. Forty maxillary canines were sectioned transversally below the cementoenamel junction to provide 4-mm-thick dentin disks that were centered in aluminum rings and embedded in acrylic resin. Root canals were prepared with tapered diamond bur. Intraradicular dentin was treated with 1% NaOCl for 30 minutes, 17% ethylenediaminetetraacetic acid for 5 minutes, and flushed with distilled water for 1 minute. The specimens were randomly distributed into 4 groups (n = 10) according to the filling material: GI, Epiphany without photoactivation; GII, Epiphany prepared with solvent without photoactivation; Gill, Epiphany followed by photoactivation; and GIV, Epiphany prepared with solvent followed by photoactivation. After the setting time, the specimens were submitted to the push-out test. The highest mean value (14.91 +/- 2.82 MPa) was obtained with Epiphany prepared with solvent followed by photoactivation (GIV), which was statistically different (P < .01) from the other groups. Groups I (8.15 +/- 2.47 MPa), II (9.46 +/- 2.38 MPa), and III (9.80 +/- 2.51 MPa) had inferior bond strength values and were statistically similar among themselves (P > .01). The resinous solvent of Epiphany system increased the bond strength of Epiphany sealer to dentin walls when followed by photoactivation. (J Endod 2009;35: 251-255)

Influence of different endodontic filling materials on root fracture susceptibility

Objective: To evaluate the influence of different endodontic materials on root fracture susceptibility. Methods: Seventy-two mandibular incisors were sectioned 1 mm below the cementoenamel junction to obtain roots of 12 mm length. Roots were submitted to chemomechanical preparation with the rotary instruments of Profile system. The obturation of root canals were performed with the following filling materials (n = 12): GI, unfilled teeth (control); GII, Endofill + gutta-percha; GIII, Sealer 26 + gutta-percha; GIV, AH Plus + gutta-percha; GV, Epiphany + gutta-percha; GVI, Epiphany + Resilon. After the sealers setting time, each root was embedded in acrylic resin. The specimens were then submitted to fracture resistance test using an Instron testing machine at 1 mm/min. Results: The ANOVA test showed no significant statistical difference (p > .05) among GI (162.16 +/- 41.4N), GII (168.46 +/- 37.5N), GIII (164.83 +/- 35.7N), GIV (168.29 +/- 38.7N), GV (172.36 +/- 20.6N) and GVI (193.11 +/- 42.8N). Conclusion: The core materials (gutta-percha or Resilon) combined with the tested endodontic sealers are not able to increase the root fracture resistance in canals submitted to chemomechanical preparation. (c) 2007 Elsevier Ltd. All rights reserved.