No abstract

No abstract

Saliva plays important roles in facilitation of a bloodmeal, lubrication of mouthparts, and parasite transmission for some vector insects. Salivary composition changes during the lifetime of an insect, and differences in the salivary profile may influence its functions. In this report, the amount and profile of salivary gland protein of the American visceral leishmaniasis vector Lutzomyia longipalpis (Lutz & Neiva, 1912) were analyzed at different times of insect development and diet. Protein content from unfed female sand flies increased significantly with age, and a significant difference was observed in sugar-fed females during the first 10 d of adult life. Salivary protein content sharply decreased 1 d after blood feeding, with gradual increase in concentration the following days. SDS-polyacrylamide gel electrophoresis analysis revealed that most polypeptides present in the saliva of sugar-fed also were present in the saliva of blood-fed females. Understanding changes in sand fly's saliva contents at distinct days after emergence and the influence of a bloodmeal in this aspect may reveal the role played by saliva during leishmaniasis transmission.

The effects of the presence of the R-phase in a near-equiatomic NiTi alloy on the mechanical responses of an endodontic instrument were studied by using finite element analysis. The input data for the constitutive model in the simulation were obtained by tensile testing of three NiTi wires: superelastic austenite NiTi, austenite + R-phase NiTi, and fully R-phased NiTi. The wires were also characterized by X-ray diffraction and differential scanning calorimetry. A commercially available endodontic instrument was scanned using microcomputed tomography, and the resulting images were used to build the geometrical model. The numerical analyses were performed in ABAQUS using load and boundary conditions based on the ISO 3630-1 specification for the bending and torsion of endodontic instruments. The modeled instrument containing only R-phase demanded the lowest moment to be bent, followed by the one with mixed austenite + R-phase. The superelastic instrument, containing essentially austenite, required the highest bending moment. During bending, the fully R-phased instrument reached the lowest stress values; however, it also experienced the highest angular deflection when subjected to torsion. In summary, this simulation showed that NiTi endodontic instruments containing only R-phase in their microstructure would show higher flexibility without compromising their performance under torsion.

The strain hardening behavior of an AISI 304 stainless steel at different temperatures was investigated in this work. Specimens were tensile tested up to rupture at temperatures of 25, 50, 75, 100, 125 and 150 ºC by using a universal testing machine with an attached environmental test chamber. The induction of martensite by strain was assessed by X-ray diffraction and Rietveld refinement. The resultant fracture morphologies were analyzed by scanning electron microscopy. The changes in the mechanical properties as a function of temperature were evaluated through the variations in the stress-strain curve and the strain hardening behavior was described in terms of strain hardening rate, instantaneous strain hardening exponent and Crussard-Jaoul analysis. Six strain hardening stages were detected at lower temperatures, transitioning into three strain hardening stages at higher temperatures. Fracture surface was ductile at all studied temperatures, although differences in terms of dimple and void morphology were observed.

No abstract

Paracoccidioidomycosis is caused by fungi of the Paracoccidioides genus and constitutes the most prevalent deep mycosis in Latin America. Toll-like receptors promote immune response against infectious agents. Recently, it was reported that TLR9 is crucial for mice survival during the first 48 h of P. brasiliensis infection. In this study, we used CPG oligodeoxynucleotide motif as an adjuvant with and without rPb27 to immunize mice against Paracoccidioidomycosis. CPG adjuvant induced differential recruitment of lymphocytes in the inflammatory process and a lower recruitment of neutrophils. In addition, CPG induced the production of pro-inflammatory cytokines such as IL-1β, TNF-α, IL-6 and IL-12; increased phagocytic ability and microbicidal activity by macrophages; and induced differential production of lgG2a and lgG2b, subtypes of Ig. Knockout mice for TLR9 and IL-12 showed higher fungal loads and rates of mortality compared to control mice after 30 days of infection. The association between CPG and rPb27 induced a high level of protection against Paracoccidioidomycosis after the first 30 days of infection but not at 60 days. Our findings demonstrate that TLR 9 plays a role in the protection induced by immunization with rPb27 and confirms the importance of TLR9 in the initial protection against Paracoccidioidomycosis.

INTRODUCTION: The goal was to develop an in-house serological method with high specificity and sensitivity for diagnosis and monitoring of Chagas disease morbidity. METHODS: With this purpose, the reactivities of anti-T. cruzi IgG and subclasses were tested in successive serum dilutions of patients from Berilo municipality, Jequitinhonha Valley, Minas Gerais, Brazil. The performance of the in-house ELISA was also evaluated in samples from other relevant infectious diseases, including HIV, hepatitis C (HCV), syphilis (SYP), visceral leishmaniasis (VL), and American tegumentary leishmaniasis (ATL), and noninfected controls (NI). Further analysis was performed to evaluate the applicability of this in-house methodology for monitoring Chagas disease morbidity into three groups of patients: indeterminate (IND), cardiac (CARD), and digestive/mixed (DIG/Mix), based on their clinical status. RESULTS: The analysis of total IgG reactivity at serum dilution 1:40 was an excellent approach to Chagas disease diagnosis (100% sensitivity and specificity). The analysis of IgG subclasses showed cross-reactivity, mainly with NI, VL, and ATL, at all selected serum dilutions. Based on the data analysis, the IND group displayed higher IgG3 levels and the DIG/Mix group presented higher levels of total IgG as compared with the IND and CARD groups. CONCLUSIONS: These findings demonstrated that methodology presents promising applicability in the analysis of anti-T. cruzi IgG reactivity for the differential diagnosis and evaluation of Chagas disease morbidity.