Computational methodology for the development of microdevices and microreactors with ANSYS CFX.

In the present paper, a computational methodology for the development of microdevices and microreactors are presented. The methodology was based on Computational Fluid Dynamics (CFD), i.e., the solution of transport equations governing the flow field. The methodology presents a step-by-step tutorial for modeling and simulation of such microdevices that can be used by beginner or experienced users. The proposed methodology was employed in two study cases: fluid mixing and fluid mixing accompanied by chemical reaction. Two new geometry designs were evaluated: a micrometric scale channel with triangular cross section (MT) and a millimeter range scaled channel (MTB). It is expect that the reported methodology contributes to the popularization of CFD usage among researchers, scientists and Microfluidic enthusiasts. Also, it can motivate future studies to focus firstly on geometry optimization by numerical simulations, providing a faster and economical way to develop microdevices. •A CFD-based methodology was presented for the development of microdevices and microreactors•The methodology can be used in distinct fluid mixing and chemical reaction systems•Numerical simulation allows a faster microdevice development procedure with costs reductions.

Protective effect of lectin from Synadenium carinatum on Leishmania amazonensis infection in BALB/c mice.

The protective effect of the Synadenium carinatum latex lectin (ScLL), and the possibility of using it as an adjuvant in murine model of vaccination against American cutaneous leishmaniasis, were evaluated. BALB/c mice were immunized with the lectin ScLL (10, 50, 100 microgram/animal) separately or in association with the soluble Leishmania amazonensis antigen (SLA). After a challenge infection with 10(6) promastigotes, the injury progression was monitored weekly by measuring the footpad swelling for 10 weeks. ScLL appeared to be capable of conferring partial protection to the animals, being most evident when ScLL was used in concentrations of 50 and 100 microgram/animal. Also the parasite load in the interior of macrophages showed significant reduction (61.7%) when compared to the control group. With regard to the cellular response, ScLL 50 and 100 microgram/animal stimulated the delayed-type hypersensitivity (DTH) reaction significantly (P < 0.05) higher than SLA or SLA plus ScLL 10 weeks after the challenge infection. The detection of high levels of IgG2a and the expression of mRNA cytokines, such as IFN-gamma, IL-12, and TNF-alpha (Th1 profiles), corroborated the protective role of this lectin against cutaneous leishmaniasis. This is the first report of the ScLL effect on leishmaniasis and shows a promising role for ScLL to be explored in other experimental models for treatment of leishmaniasis.

Levels of immunoglobulin A1 and messenger RNA for interferon gamma and tumor necrosis factor alpha in total saliva from patients with diabetes mellitus type 2 with chronic periodontal disease.

BACKGROUND: Diabetes mellitus and periodontal disease have high incidence in the general population and are associated with various degrees of dysfunction in the immune system. It has been shown that diabetic patients with severe periodontal disease have more complications of diabetes and less effective metabolic control compared with diabetic patients with healthy gingiva. Patients with diabetes and severe periodontal disease present higher levels of serous immunoglobulin A (IgA). Elevation of the IgA1 isotype is thought to contribute to this phenomenon. Another important event in the diabetes-periodontitis association is the disturbance in local and systemic production of inflammatory cytokines. OBJECTIVE: In this study we tested the hypothesis that type 2 diabetic patients with chronic moderate periodontal disease have differences in salivary IgA1 titers and cytokine expression when compared with the chronic severe periodontal disease cases. METHODS: We utilized a jacalin-IgA capture assay to determine the IgA1 titers in total saliva and reverse transcriptase-polymerase chain reaction to detect mRNA for interferon gamma (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha) in total saliva samples of 13 patients with chronic moderate periodontal disease and 10 with chronic severe periodontal disease. RESULTS AND CONCLUSIONS: We observed a predominance of IgA1 titers of 64 (45.5%) in saliva samples from chronic severe periodontal disease patients and titers averaging 512 (30.8%) in chronic moderate periodontal disease patients. We detected mRNA for IFN-gamma in six out of 10 chronic severe periodontal disease subjects and in two out of 13 chronic moderate periodontal disease patients. TNF-alpha expression was similar in both groups. Our data suggest that higher levels of IgA1 may exert partial protection of the periodontal tissue in chronic moderate periodontal disease diabetic patients when compared to severe periodontal disease. Despite the small number of patients, IFN-gamma expression had a trend association with severity of periodontitis and TNF-alpha gene expression did not correlate with severity of periodontal disease.

Comparative effect of ion calcium and magnesium in the activation and infection of the murine macrophage by Leishmania major.

Amastigotes of Leishmania major have a great ability to evade destruction in host cells. This study investigated the activation in resident, inflammatory macrophages and J774 cells in vitro treated with lipopolysaccharide (LPS), soluble Leishmania antigen (SLA), calcium ionophore (CaI) and magnesium (Mg2+) alone or combined. An increase in nitric oxide (NO) production was observed in J774 or inflammatory macrophages treated with LPS alone or in combination with SLA and CaI. The same treatments did not affect the NO release by resident macrophages. There was no interference in uptake of L. major but CaI decreased intracellular proliferation of the parasite. This study demonstrated the importance of CaI in decreasing L. major proliferation inside murine macrophages while Mg2+ seemed to increase parasite proliferation. These finding may help to understand the events involved in host cells' clearance of this pathogen.

Comparative effect of ion calcium and magnesium in the activation and infection of the murine macrophage by Leishmania major

Amastigotes of Leishmania major have a great ability to evade destruction in host cells. This study investigated the activation in resident, inflammatory macrophages and J774 cells in vitro treated with lipopolysaccharide (LPS), soluble Leishmania antigen (SLA), calcium ionophore (CaI) and magnesium (Mg2+) alone or combined. An increase in nitric oxide (NO) production was observed in J774 or inflammatory macrophages treated with LPS alone or in combination with SLA and CaI. The same treatments did not affect the NO release by resident macrophages. There was no interference in uptake of L. major but CaI decreased intracellular proliferation of the parasite. This study demonstrated the importance of CaI in decreasing L. major proliferation inside murine macrophages while Mg2+ seemed to increase parasite proliferation. These finding may help to understand the events involved in host cells' clearance of this pathogen..