Top PDF Peristaltic transport of Conducting Bingham fluid in contact with a Newtonian fluid in a channel

Peristaltic transport of Conducting Bingham fluid in contact with a Newtonian fluid in a channel

Peristaltic transport of Conducting Bingham fluid in contact with a Newtonian fluid in a channel

Brasseur et al., (1987) made a significant contribution on the peristaltic transport of two immiscible fluids in a channel with flexible walls and have proved the invalidity of the analysis mentioned above in the limit of infinite peripheral layer viscosity. This problem is solved for axisymmetric case by Ramachandra Rao and Usha et al., (1995). Usha and Ramachandra Rao (1997) discussed the peristaltic pumping of two layered power-law fluids in an axisymmetric tube. The interface between the two layers is determined from a transcendental equation in the core radius. Comparani and Mannucci (1998) analysed the flow of a Bingham fluid in contact with a Newtonian fluid in a channel. Existence and uniqueness theorems are proved for the solution of the problem. Vajravelu et al., (2005 a,b) studied Peristaltic Transport of a Herschel-Bulkley fluid in a channel and an inclined tube. Radhakrishnamacharya et al., (2007) studied Influence of wall properties on peristaltic transport with heat transfer. Srinivas et al., (2009) studied the influence of slip conditions, wall properties and heat transfer on MHD peristaltic transport. Hayat et al., (2010) analyzed the Series solution for MHD channel flow of Jeffrey fluid. The slip and induced magnetic field effects on the Peristaltic transport with heat and mass transfer is analysed by Hayat et al.,(2012).
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A Semi-Analytical Solution for a Porous Channel Flow of a Non-Newtonian Fluid

A Semi-Analytical Solution for a Porous Channel Flow of a Non-Newtonian Fluid

The theory of couple stress fluids proposed by Stokes (1966) shows all the important features and effects of couple stresses in fluid medium. The basic equations are similar to Navier Stokes equations. The importance of couple stress effects in flow between parallel porous plates have been analyzed by several researchers. Kabadi (1987) has studied the flow of couple stress fluid between two parallel horizontal stationary plates with fluid injection through the lower porous plate. Ariel (2002) has provided an exact solution for flow of second grade fluid through two parallel porous flat walls. Kamisili (2006) has analyzed the laminar flow of a non-Newtonian fluid in channels with the upper plate stationary, while the lower plate is uniformly porous and moving in x-direction with constant velocity. Srinivacharya et al. (2009) have analyzed the flow and heat transfer of couple stress fluid in a porous channel with expanding and contracting walls. Srinivacharya et al. (2010) have investigated the flow of couple stress fluid between two porous plates for suction at both plates with different permeabilities.
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Steady and unsteady laminar flows of newtonian and generalized newtonian fluids in a planar T-junction

Steady and unsteady laminar flows of newtonian and generalized newtonian fluids in a planar T-junction

What is clear from this review is the lack of proper validation and assessment of numerical accu- racy in works on steady and pulsatile flows of Newtonian as well as non-Newtonian fluids through T-junctions, and that constitutes the objective of the present investigation. In this first contribution, the emphasis is on quantitative results for the Newtonian two-dimensional case, of benchmark quality, before embarking upon more complicated three-dimensional and non-Newtonian calcula- tions. Nevertheless, some GNF simulations are also presented, enough to show how misleading the assumption of constant viscosity can be. In a second paper we shall deal with the GNF case in more depth. The remaining part of this paper is organized as follows: the governing equations and the numerical methods used are presented in Section 2. The results and discussion section is organized in four parts: the first part starts with the presentation of the flow geometry, computational domain and meshes used, then it discusses issues of mesh convergence and space discretization and finally it presents accurate predictions of steady T-junction laminar flow of Newtonian fluids as a function of the flow rate ratio and Reynolds number. The second part assesses the time accuracy of unsteady flow calculations by comparing predictions of unsteady laminar channel flow of Newtonian fluids with the corresponding analytical solution. Results are presented in part three for the unsteady flow in a diverging laminar 90 ◦ T-junction with a Newtonian fluid and finally, in part 4, for a Generalized Newtonian fluid. In all cases, the fluids selected have properties that closely follow those of blood. The paper ends with a summary of the main conclusions.
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Mixed convection flow of nanofluid in presence of an inclined magnetic field.

Mixed convection flow of nanofluid in presence of an inclined magnetic field.

Peristaltic motion is now an important research topic due to its immense applications in engineering and physiology. This type of rhythmic contraction is the basis of peristaltic pumps that move fluids through tubes without direct contact with pump compo- nents. This is a particular advantage in biological/medical applications where the pumped material need not to contact any surface except the interior of the tube. The word ‘‘peristalsis’’ comes from a Greek word ‘‘Peristaltikos’’which means clasping and compressing. The peristaltic flow has specific involvement in the transport of urine from kidney to the bladder, chyme movement in gastrointestinal tract, movement of ovum in the female fallopian tubes, blood circulation in the small blood vessels, roller and finger pumps, sanitary fluid transport and many others. Latham [1] and Shapiro et al. [2] reported initial studies for the peristaltic flow of viscous fluid. Since then ample attempts have been made for peristalsis in symmetric flow configuration (see few recent studies [3–8]). On the other hand the physiologists argued that the intra-uterine fluid flow (because of mymometrical contractions) represents peristaltic mechanism and the myome- trical contractions may appear in both asymmetric and symmetric channels [9]. Hence some researchers [10–15] discussed the peristaltic transport in an asymmetric channel with regard to an application of intra-uterine fluid flow in a nonpregnant uterus.
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Unsteady Free Convective Flow of a Temperature Varying Electrically Conducting Fluid

Unsteady Free Convective Flow of a Temperature Varying Electrically Conducting Fluid

In this paper, we are investigating the fully developed free convection laminar flow of an incompressible viscous electrically conducting fluid between two vertical parallel plates in the presence of a uniform induced magnetic field applied transversely to the flow. This induces a field along the lines of motion which varies transversely to the flow. The temperature of the fluid motion is assumed to be changing with time. The analytical solutions for velocity, induced magnetic field and the temperature distributions are obtained for small and large magnetic Reynolds numbers, R m . The skin frictions at the two plates are obtained for different magnetic field parameters and are plotted graphically. The rate of heat transfer are also obtained and are plotted graphically. The problem has also been solved for thermometric case i.e. when the lower plate is adiabatic.
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Braz. J. Phys.  vol.33 número4

Braz. J. Phys. vol.33 número4

One of the main issues related to this observational re- sults, is the nature of this negative pressure fluid. The position of the first acoustic peak in the spectrum of the anisotropy of cosmic microwave background radiation is re- lated to the total density of the Universe. In spite of the fact that there is not until now doubtless observational results indicating where precisely this first acoustic peak is located, the recent data coming from BOOMERANG and MAXIMA projects indicate that the density of the Universe is near the critical density [6, 7]. Hence, it can be assumed that the Uni- verse is spatially or nearly spatially flat. On the other hand, the clustered mass is responsable for 0.3 ∼ 0.4 of the crit- ical density. Consequently, from this data it is possible to conclude that 0.7 ∼ 0.6 of the total matter of the Universe is a smooth component which is generally called dark energy.
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The Influence Of CSR Awareness On Consumer Purchase Decision Of A Telecommunication Network In Ghana A Case Of La Nkwantanag Madina Municipality

The Influence Of CSR Awareness On Consumer Purchase Decision Of A Telecommunication Network In Ghana A Case Of La Nkwantanag Madina Municipality

The premise of the corporate social responsibility movement is that ‗corporations, because they are the dominant institution of the planet, must squarely face and address the social and environmental problems that afflict humankind. However, companies have a choice with regard to the causes they support and how they convey this information. These choices may, or may not, reflect a sincere interest in the cause (in addition to image-promotional motives). Previous research suggests that consumers assess sincerity in the context of consumer–salesperson interaction (DeCarlo, 2005). Campbell and Kirmani (2000) found that when ulterior motives were accessible, consumers inferred an underlying persuasion attempt and the target salesperson were perceived as less sincere. As noted earlier, in the context of CSR, the type of cause that the company supports may increase the salience of firm-serving benefits (Forehand & Grier, 2003). Causes that are related with the company‘s business should increase the salience of firm-serving benefits. Today, corporations know that CSR is inextricably linked to how customers make purchase decision of the organizations products and service (Ahearne, Bhattacharya and Gruen, 2010). In Ghana, specifically with the telecommunication industry, the business environment is typically competitive, characterized by a legal environment aimed at ethical behaviors on the part of businesses, and societal expectations that businesses should be more ethical and socially responsible. Thus, in decision making processes, companies try to avoid actions that may breach any regulation or negatively impact their reputation in order to avoid consumer dissatisfaction. In Ghana there is an organization that monitors the activities of the telecommunication companies in the country, which is the National Communication Authority (NCA). The telecommunication companies in Ghana are MTN Ghana, Tigo Ghana, Airtel, GLO, Vodafone Ghana Ltd, Airport-Accra, and Expresso Ghana. Previous studies on consumers‘ attitudes on CSR and CSR‘s impact on consumer behavior and consumption decisions are quite general (Becker-Olsen, Cudmore & Hill, 2006; Öberseder, Schlegelmilch & Gruber, ______________________
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J. Braz. Soc. Mech. Sci. & Eng.  vol.33 número3

J. Braz. Soc. Mech. Sci. & Eng. vol.33 número3

Kuru et al. (1995) presented a theoretical and experimental study of the initial instabilities on a granular bed on a horizontal pipe flow, which is a case without free-surface effects. Their experimental test section was a 31.1 mm diameter pipe, 7 m long, and they employed a mixture of water and glycerin as the fluid media and glass beads as the granular media. More details can be found in Kuru et al. (1995). In each experimental test, an initially plane granular bed was submitted to a specific flow of liquid and, when the ripples were visible, the tests were stopped. The wavelength of these ripples was then measured and associated to the initial instabilities. However, they reported that the amplitudes of the ripples were 2-3 mm (10 to 20 times the grain diameters), so that they correspond in fact to the early stages of the nonlinear phase. The fact that they didn’t notice any length-scale variation from the time when the ripples were first visualized to the complete stop of the experiment (this time interval is not negligible compared to the time-scale for ripples formation, of only a few seconds) means that these forms saturate after their initial growth, agreeing with the nonlinear analysis developed in this paper.
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Mixed Convection Flow of Couple Stress Fluid in a Vertical Channel with Radiation and Soret Effects

Mixed Convection Flow of Couple Stress Fluid in a Vertical Channel with Radiation and Soret Effects

Understanding and modeling the flows of non- Newtonian fluids are of both fundamental and practical significance in the industrial and engineering applications. With the growing importance of non- Newtonian fluids in modern technology and industries, the investigations on such fluids are desirable. The theory of polar fluids and related theories are models for fluids whose microstructure is mechanically significant. The micro-continuum theory of couple stress fluid proposed by Stokes (1966), defines the rotational field in terms of the velocity field for setting up the constitutive relationship between the stress and strain rate. Also, the study of a couple stress fluids is very useful in understanding various physical problems because it possesses the mechanism to describe rheological complex fluids such as liquid crystals and human blood. The rheological characteristics of such fluids are important in the flows of nuclear fuel slurries, lubrication with heavy oils and greases, paper coating, plasma and mercury, fossil fuels, polymers etc. In view of applications, Sunil and Devi (2012) described the global stability for thermal convection in a couple stress fluid saturating in a porous medium with temperature-pressure dependent viscosity using Galerkin method. Srinivasacharya and Kaladhar (2011, 2012) discussed the convection flow of couple stress fluid with Hall and Ion-slip effects in different geometries. Recently, Muthuraj et al. (2013) have studied the heat and mass transfer effects on MHD flow of a couple-stress fluid in a horizontal wavy channel with viscous dissipation and porous medium. Most recently Hayat et al. (2013) analyzed the stagnation point flow of couple stress fluid with melting heat transfer and the analytical study of Hall and Ion-slip effects on mixed convection flow of couple stress fluid between parallel disks have been presented by Srinivasacharya and Kaladhar (2013).
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Fluid Dynamics and Heat Transfer in Non-Newtonian Annular Cylindrical Solidification of a Binary Alloy

Fluid Dynamics and Heat Transfer in Non-Newtonian Annular Cylindrical Solidification of a Binary Alloy

Solidification with natural convection for a non- Newtonian Al-Si 1.7% alloy of the Otswald de Waele type in the annular space between two horizontal concentric cylinders exhibits highest velocities at the beginning in materials with pseudo plastic behavior (n=0.5). The solidification process is faster when n= 0.5 than when it is Newtonian (n=1) or when a dilatant fluid model is used (n=1.5). Multicellular flow is enhanced as the Rayleigh number increased. Prediction with the finite volume method can be made using non-uniform grids with 100 x 60 nodes and dynamic time paths in the range 1x10 -5 s ≤ ∆t ≤ 0.005s. CPU times increased ten times for the pseudo plastic fluid or for the highest Ra.
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Unsteady Hydromagnetic Natural Convection Flow past an Impulsively Moving Vertical Plate with Newtonian Heating in a Rotating System

Unsteady Hydromagnetic Natural Convection Flow past an Impulsively Moving Vertical Plate with Newtonian Heating in a Rotating System

boundary layer flow along a heated vertical flat plate embedded in a fluid-saturated porous medium, which was investigated by Cheng and Minkowycz (1977). They obtained similarity solutions for the case when wall temperature varies as a power function of the distance from the leading edge. Nakayama and Koyama (1987) analyzed combined free and forced convection flow in Darcian and non- Darcian porous medium. Lai and Kulacki (1991) studied non-Darcy mixed convection flow along a vertical wall in a fluid saturated porous medium. Hsieh et al. (1993) obtained non-similar solution for free and forced convection flow from a vertical surface in a porous medium. Rees (1999) analyzed free convection boundary layer flow from an isothermal vertical flat plate embedded in a fluid saturated layered porous medium. Jana et al. (2012) studied natural convection boundary layer flow from an inclined flat plate with finite dimensions embedded in a porous medium in a rotating environment. Khan and Pop (2013) investigated the Cheng and Minkowycz problem for triple diffusive natural convection boundary layer flow past a vertical plate in a porous medium. Reddy et al. (2013) studied unsteady hydromagnetic natural convection flow past a moving vertical plate in a porous medium in the presence of radiation and chemical reaction. Comprehensive reviews of convective flow in porous media are candidly presented in the form of books and monographs by Ingham and Pop (2002), Ingham et al. (2004), Vafai (2005) and Nield and Bejan (2006).
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Influence of Hall Current on MHD Flow and Heat Transfer over a slender stretching sheet in the presence of variable fluid properties

Influence of Hall Current on MHD Flow and Heat Transfer over a slender stretching sheet in the presence of variable fluid properties

However, not much attention has been paid to the effects of Hall currents. When the magnetic field is strong and the density of electrons is small, the Hall effect cannot be ignored as it has a significant effect on the flow pattern of an ionized gas. However, for ionized gases, the conventional MHD is not valid. In an ionized conducting fluid where the density is low and/or magnetic field is very strong, the conductivity normal to the magnetic field is reduced due to the free spiraling of electrons and a current is induced in a direction normal to both electric and magnetic fields. This phenomenon is called Hall effect. The effect of Hall current cannot be neglected when the medium is rarefied or in a strong magnetic field. The study of MHD flows with Hall current has important industrial applications in many geophysical and astrophysical situations and in several engineering problems such as Hall accelerators, Hall effect sensors, constrictions of turbines, centrifugal machines, and flight magneto-hydrodynamics. In view of these applications, it is essential to analyze the influence of Hall current on the fluid flow. Gupta [16] considered a strong magnetic field which permeated the fluid and investigated the effect of Hall current on the fluid past an infinite porous flat plate and Jana et al. [17] continued the work of Ref. [16] for different physical situations. Hossain and Rashid [18] extended the work of Gupta [16] to unsteady free convection flow. Further, Rana et al. [19] analyzed the effect of Hall current on Hartmann flow between two parallel electrically insulated infinite planes. Chaudhary and Jha [20] studied the effect of heat and mass transfer on the flow of elastico-viscous fluid past an impulsively started infinite vertical plate with mass transfer and Hall effect taken into account. Recently, Hayat et al
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Dual Solutions for Nonlinear Flow Using Lie Group Analysis.

Dual Solutions for Nonlinear Flow Using Lie Group Analysis.

`The aim of this analysis is to investigate the existence of the dual solutions for magnetohy- drodynamic (MHD) flow of an upper-convected Maxwell (UCM) fluid over a porous shrinking wall. We have employed the Lie group analysis for the simplification of the nonlinear differ- ential system and computed the absolute invariants explicitly. An efficient numerical tech- nique namely the shooting method has been employed for the constructions of solutions. Dual solutions are computed for velocity profile of an upper-convected Maxwell (UCM) fluid flow. Plots reflecting the impact of dual solutions for the variations of Deborah number, Hart- man number, wall mass transfer are presented and analyzed. Streamlines are also plotted for the wall mass transfer effects when suction and blowing situations are considered.
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Numerical Study on MHD Mixed Convection Flow in a Vertical Insulated Square Duct with Strong Transverse Magnetic Field

Numerical Study on MHD Mixed Convection Flow in a Vertical Insulated Square Duct with Strong Transverse Magnetic Field

Sposito and Ciafalo (2006) studied fully developed flow of an electrically conducting fluid between parallel walls under the simultaneous influence of a driving pressure head, buoyancy and MHD forces, where the fluid was assumed to be internally heated and the flow was modeled as one-dimensional and incompressible. Al-Khawaja et al. (1994) solved numerically the problem of fully developed, laminar, steady, forced convection heat transfer in an electrically conducting fluid flowing in an electrically insulated, horizontal circular pipe in a vertical uniform transverse magnetic. Al-Khawaja et al. (1999) also studied the same problem for free- and-forced convection flow numerically using finite difference schemes for Grashof numbers 0 to 106 and Hartmaan numbers 0 to 500. Umavathi and Malashetty (2005) solved the problem of combined free and forced convective MHD flow in a vertical channel by taking into account the effect of viscous and ohmic dissipations, analytically by perturbation series method and numerically by finite difference technique. Umavathi and Chamkha (2011) analyzed the effect of heat and mass transfer on mixed convective flow of a viscous incompressible fluid past a vertical infinite plate in the presence of heat source or sink. Garandet and Alboussiere (1992) proposed analytical solutions to the equations of MHD that was used to model the effect of a transverse magnetic field on buoyancy driven convection in a two-dimensional cavity, in the case of high Hartmaan number limit. Blosseville et al. (2007) investigated analytically a fully developed buoyant flow in a straight, horizontal rectangular duct with an axial temperature gradient in an arbitrary oriented, transverse magnetic field with insulated walls. Aruna et al. (2011) studied the developed MHD mixed convection flow in a vertical channel, where the problem was described by means of partial differential equations and the solutions were obtained by an implicit finite difference technique coupled with a marching
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Optimization of a perfusion bioreactor for tissue engineering

Optimization of a perfusion bioreactor for tissue engineering

In perfusion bioreactors nutrient delivery is not performed only on the periphery of the scaffold it also covers the internal zones (Chen and Hu, 2006; Martin et al., 2004). In addition, the continuous movement of the medium contributes to a more homogenous distribution of cells in the structure and also for greater homogenization of concentrations of gases, nutrients, metabolites and growth factors present in the medium (Korossis et al., 2005). The success of this type of bioreactors depends on the following factors: (1) the relationship between the fluid velocity and the stage of cell maturation; (2) balance between the supply of nutrients and removing waste from the cells; (3) shear stresses exerted by the fluid passage and; (4) ability to retain the extra-cellular matrix (Martin et al., 2004). One of the limitations is the difference between stress and fluid speeds on the scaffold extremities compared with the inner part. This phenomenon can cause non-homogeneous distributions of cells or even cell drag if the fluid velocity is very high (Zhang et al., 2009).
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Penicilinoterapia intravenosa em altas doses na neurossífilis: estudo de 62 casos. I. Avaliação clínica.

Penicilinoterapia intravenosa em altas doses na neurossífilis: estudo de 62 casos. I. Avaliação clínica.

— Penicillin concentrations in the cerebrospinal fluid after benzathine penicillin and probenecid in the treatment of syphilis.. — Penicillin concentrations in cerebrospinal fluid after[r]

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Numerical analysis of capillary compensated micropolar fluid lubricated hole-entry journal bearings

Numerical analysis of capillary compensated micropolar fluid lubricated hole-entry journal bearings

2006). They compared the bearing operating under micropolar lubricant with similar bearing operating under Newtonian lubricant. Later on, in 2011, they investigated finite journal bearing lubricated under micropolar fluids (Wang et al., 2011). Krasowski (Krasowski, 2008) presented hydrodynamic pressure distribution and force capacity of slide journal bearing under micropolar lubricant. In his study hydrodynamic pressure has been presented in dimensionless form which depends on micropolar parameters of lubricant. Recently, Lin and co-workers (Lin et al., 2012) reported the effects of micropolar lubricant on stiffness and damping coefficients of parabolic-film slider bearings using closed-form solution. Later on, other studies (Ram and Sharma, 2012; Sharma and Ram, 2011; Ram and Sharma, 2015; Ram et al., 2015) presented the effect of micropolar lubricants on orifice compensated hole-entry and symmetric/asymmetric slot- entry journal bearings. They found that the proper selection of orifice restrictor design parameter and micropolar parameters of lubricant enhance the minimum fluid film thickness and stiffness of the bearing. Further, it was found that the fluid film stiffness and threshold speed increase for constant slot-entry restrictor parameter when bearing is lubricated with micropolar fluid. Ram (Ram, 2016) found that when the bearing operates under higher value of Reynolds number (20000), the fluid thickness and stiffness coefficients at constant restrictor design parameters is superior as compared to the bearing operates under laminar regime.
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Green Facade As A Prototype Way Of Extending Natural Sphere In A Hyper Dense Urban Context.

Green Facade As A Prototype Way Of Extending Natural Sphere In A Hyper Dense Urban Context.

Abstract: Analysis of vertical (greenery) landscape, an alternative to our historical horizontal landscape which lost its control due to urbanization and deforestation. Urban cites are increasingly expanding upwards and spreading horizontal which is now a direct negative impact on landscape and health. As Population increase there is demand of land for shelter and health also. This paper seeks to analysis if vertical landscape helps to link this gap which is increasingly expanding – (shortages of clean air, natural environment, exposed to direct light etc.).The paper sorely use three case studies which are in three different climates so as to give wider decision when applying vertical landscaping. The selection of case studies is based on their role as pioneers of vertical landscape and the benefit which is now at stake. This is achieved through research and literature reviews on those case studies. This paper seeks to provide better alternative when design building with vertical landscape, and tries to lay out some of the critical principles to consider when design a green façade (vertical landscape). Finally the writer define the benefit of using vertical landscape to natural environment, manmade environment and users as well.
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Applications of Mathematics in Fluid Dynamics

Applications of Mathematics in Fluid Dynamics

Here p (x, t) is the pressure field, and is the source of non-locality of the problem. Indeed, the continuity equa- tion for incompressible flows reads as a solenoidality prop- erty, ∇ ⋅ u = 0, and pressure is required to satisfy a Pois- son equation. Therefore, even if (2) is in principle evalu- ated locally at one single point, actually it contains a term which represents a contribution coming from a spatial inte- gral on the whole domain, as the propagation velocity of any disturbance is infinite. Despite this difficulty, incompress- ibity is a scheme widely used for the simplifications it brings about, and is usually abandoned only when compressibility effects cannot be neglected, most notably because the veloc- ities into play are not negligible with respect to the sound speed [13]. In this latter case, the mass density varies. Also thermal effects can come into play and modify the param- eters, in which case also the evolution of the temperature field must be taken into account, along with a suitable equa- tion of state. Even more problematically, also viscosity can be different from a constant, and then the fluid under con- sideration is dubbed as non-Newtonian and described by a different equation.
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Detection of circulating gp43 antigen in serum, cerebrospinal fluid, and bronchoalveolar lavage fluid of patients with paracoccidioidomycosis

Detection of circulating gp43 antigen in serum, cerebrospinal fluid, and bronchoalveolar lavage fluid of patients with paracoccidioidomycosis

Paracoccidioidomycosis (PCM) is a systemic granulomatous disease caused by Paracoccidioides brasiliensis, a thermal di- morphic fungus. PCM is widespread in Latin America, mainly in Brazil, Argentina, Colombia, and Venezuela, affecting mainly rural workers. According to McEwen et al. (22), ap- proximately 10 million people may be infected with this fungus, and up to 2% of them may develop the disseminated forms of the disease. The incidence may increase due to forest destruc- tion and a rise in iatrogenic immunosuppression procedures (39). The acute or subacute form of PCM affects both sexes and chiefly involves the reticuloendothelial system. The chronic form affects adult males with predominantly pulmo- nary and/or mucocutaneous involvement (12). A definitive di- agnosis is usually made by visualization or isolation of the fungus from the lesions, which is time-consuming and lacks sensitivity. Detection of specific antibodies in serum has also been one of the main tools for the diagnosis of PCM and may be useful to monitor the evolution of the disease and its re- sponse to treatment (24). The most common serological tests used for diagnosis are immunodiffusion (4, 31), immunoenzy- matic assays (3, 5, 25), and counterimmunoelectrophoresis (7). Unfortunately, there is extensive antigenic cross-reactivity be-
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