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Reservoir simulation is the combination of physics, mathematics, reservoir engineering, and computer programming for predicting the performance of a hydrocarbon reservoir under various operating conditions. The necessity of optimizing oil extraction methods is to increase the efficiency of a hydrocarbon reservoir under various operating conditions. Therefore, in a hydrocarbon recovery project that may involve hundreds of millions of dollars in investments, the risk associated with using the best method for the desired outcome must be evaluated and minimized. Finding an optimal model for static reservoir simulation through fluid flow model is the main goal of this paper. For this purpose, first of all, artificial data of porosity and permeability was generated, and then these data were used for geostatistical simulation. Sequential Gaussian Simulation (SGS) method was used for static simulation of a region and for each of two static parameters, 25 realizations were obtained. The realizations of SGS were randomly entered in the dynamic model of the reservoir. Dynamic model was coded by Python for slightly-compressible fluid flow equations in three dimensions and the pressure in each of the blocks in the oil production reservoir was determined. For each category, the least Sum of Squared Errors (SSE) was determined and then the corresponding static model was selected as the desired static model. With a reliable static model, it is possible to define different locations for designing injection and oil production wells, potential intelligent wells areas, as well as optimizing the management of a reservoir, which leads to costs reduction and, at the same time, increase in oil production. [ABSTRACT FROM AUTHOR]

Abstract Background Viral myocarditis is a major cause of sudden unexpected death in children and young adults. Until recently, coxsackievirus B3 (CVB3) has been the most commonly implicated virus in myocarditis. At present, no standard diagnosis is generally accepted due to the insensitivity of traditional diagnostic tests. This has prompted health professionals to seek new diagnostic approaches, which resulted in the emergence of new molecular pathological tests and a more detailed immunohistochemical and histopathological analysis. When supplemented with immunohistochemistry and molecular pathology, conventional histopathology may provide important clues regarding myocarditis underlying etiology. Methods This study is based on post-mortem samples from sudden unexpected death victims and controls who were investigated prospectively. Immunohistochemical investigations for the detection of the enteroviral capsid protein VP1 and the characterization and quantification of myocardial inflammatory reactions as well as molecular pathological methods for enteroviral genome detection were performed. Results Overall, 48 sudden unexpected death victims were enrolled. As for controls, 37 cases of unnatural traffic accident victims were studied. Enterovirus was detected in 6 sudden unexpected death cases (12.5 %). The control samples were completely enterovirus negative. Furthermore, the enteroviral capsid protein VP1 in the myocardium was detected in enterovirus-positive cases revealed by means of reverse transcriptase-polymerase chain reaction (RT-PCR). Unlike control samples, immunohistochemical investigations showed a significant presence of T and B lymphocytes in sudden unexpected death victims. Conclusions Our findings demonstrate clearly a higher prevalence of viral myocarditis in cases of sudden unexpected death compared to control subjects, suggesting that coxsackie B enterovirus may contribute to myocarditis pathogenesis significantly.

Leishmaniasis is the 3rd most challenging vector-borne disease after malaria and lymphatic filariasis. Currently, no vaccine candidate is approved or marketed against leishmaniasis due to difficulties in eliciting broad immune responses when using sub-unit vaccines. The aim of this work was the design of a particulate sub-unit vaccine for vaccination against leishmaniasis. The poly (D,L-lactide) nanoparticles (PLA-NPs) were developed in order to efficiently adsorb a recombinant L. major histone H2B (L. major H2B) and to boost its immunogenicity. Firstly, a study was focused on the production of well-formed nanoparticles by the nanoprecipitation method without using a surfactant and on the antigen adsorption process under mild conditions. The set-up preparation method permitted to obtain H2B-adsorbed nanoparticles H2B/PLA (adsorption capacity of about 2.8% ( w / w )) with a narrow size distribution (287 nm) and a positive zeta potential (30.9 mV). Secondly, an in vitro release assay performed at 37 °C, pH 7.4, showed a continuous release of the adsorbed H2B for almost 21 days (30%) from day 7. The immune response of H2B/PLA was investigated and compared to H2B + CpG7909 as a standard adjuvant. The humoral response intensity (IgG) was substantially similar between both formulations. Interestingly, when challenged with the standard parasite strain (GLC94) isolated from a human lesion of cutaneous leishmaniasis, mice showed a significant reduction in footpad swelling compared to unvaccinated ones, and no deaths occurred until week 17th. Taken together, these results demonstrate that PLA-NPs represent a stable, cost-effective delivery system adjuvant for use in vaccination against leishmaniasis.

Coxsackieviruses B (CV B) are known as the most common viral cause of human heart infections. Cardiac inflammations contribute to sudden unexpected death (SUD) significantly. The diagnosis remains difficult with the traditional diagnostic tests and must be substantially improved. This has prompted health professionals to seek new diagnostic procedures which may provide important clues regarding underlying etiology. The present study is based on patients with infectious heart diseases and SUD victims with no relevant pathologies. They were investigated for possible CV-B infection. Patients with coronary artery diseases and unnatural road and domestic accident victims served as controls. The samples were studied for CV-B applying PCR. Histopathology for inflammatory markers, immunohistochemistry (IHC) for immune inflammatory cells and the enteroviral VP1-capsid protein were performed. Overall, 102 patients and 87 SUD victims were studied. As controls, 100 patients and 54 SUD unnatural accident victims were enrolled. CV-B were detected in 28 patients and 15 SUD victims. The control group samples were completely virus negative. Compared to controls, IHC revealed a significant presence of T and B lymphocytes within the myocardium. Furthermore, enteroviral VP1-capsid protein were detected from samples by IHC. Applying a comprehensive combination of methods, our results demonstrate the involvement of CV-B in cases of heart infection suggesting they play a significant role in SUD. Our results emphasize the importance of opting for a combination of methods., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Sudden infant death (SID) is an unresolved problem of high relevance and previous studies have indicated a role of viral heart infections. The diagnosis remains difficult in clinical practice using routine diagnostic tests and must be substantially improved. A prospective study based on post-mortem samples from SID victims whose heart disease was not clinically recognized was conducted for 4 years in a Tunisian University Hospital. Pediatric cases of unnatural death served as controls. Both SID victims and controls were investigated for possible coxsackievirus-B (CV-B) infection in heart tissue. During the study period, 39 cases with a male predominance (77%) were reported. There was no positive family history of coronary artery disease among the victims. In 35 cases (90%), low birth weight and/or critical development period were reported. All SID victims had complained of mild fever and insomnia for a few days preceding death, which required infectious laboratory investigations marked with an elevated white blood cell count (WBC) and C-reactive protein (CRP). The cardiac biomarkers were also elevated. The histopathological investigations of the heart tissue samples revealed signs of myocardial and pericardial inflammation. Enterovirus was detected by immunohistochemistry (IHC) and PCR from myocardial samples from 6 cases (15.3%) having myocarditis and 3 cases (7.7%) having perimyocarditis. The current study is of great interest and is aimed at urging health professionals to adopt systematically long intensive heart care in infants with underlying vulnerability as well as new diagnostic approaches including histopathology complemented with IHC and molecular pathology., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Scorpion envenoming represents a public health issue in subtropical regions of the world. Treatment and prevention need to promote antitoxin immunity. Preserving antigenic presentation while removing toxin effect remains a major challenge in toxin vaccine development. Among particulate adjuvant, particles prepared with poly (D,L-lactide) polymer are the most extensively investigated due to their excellent biocompatibility and biodegradability. The aim of this study is to develop surfactant-free PLA nanoparticles that safely deliver venom toxic fraction to enhance specific immune response. PLA nanoparticles are coated with AahG50 (AahG50/PLA) and BotG50 (BotG50/PLA): a toxic fraction purified from Androctonus australis hector and Buthus occitanus tunetanus venoms, respectively. Residual toxicities are evaluated following injections of PLA-containing high doses of AahG50 (or BotG50). Immunization trials are performed with the detoxified fraction administered alone without adjuvant. A comparative study of the effect of Freund is also included. The neutralizing capacity of sera is determined in naive mice. Six months later, immunized mice are challenged subcutaneously with increased doses of AahG50. Subcutaneous lethal dose 50 (LD50) of AahG50 and BotG50 is of 575 μg/kg and 1300 μg/kg respectively. By comparison, BotG50/PLA is totally innocuous while 50% of tested mice survive 2875 μg AahG50/kg. Alhydrogel and Freund are not able to detoxify such a high dose. Cross-antigenicity between particulate and soluble fraction is also, ensured. AahG50/PLA and BotG50/PLA induce high antibody levels in mice serum. The neutralizing capacity per mL of anti-venom was 258 μg/mL and 186 μg/mL calculated for anti-AahG50/PLA and anti-BotG50/PLA sera, respectively. Animals immunized with AahG50/PLA are protected against AahG50 injected dose of 3162 μg/kg as opposed all non-immunized mice died at this dose. We find that the detoxification approach based PLA nanoparticles, benefit the immunogenicity and protective efficacy of venom immunogen., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Coxsackieviruses B (CV‑B) are known as the most common viral cause of human heart infections. The aim of the present study was to assess the potential role of CV‑B in the etiology of infectious heart disease in hospitalized patients. The present study is based on blood, pericardial fluid and heart biopsies from 102 patients and 100 control subjects. All of the samples were examined for the detection of specific enteroviral genome using the reverse transcription polymerase chain reaction (RT‑PCR) and sequence analysis. Immunohistochemical investigations for the detection of the enteroviral capsid protein, VP1, from the biopsies were performed. The samples were cultured on confluent KB monolayer cell line for possible virus isolation. The epidemiological data were also collected. CV‑B was detected in 28 of the 102 patients. The sequence analysis demonstrated that 27 strains were identical to CV‑B3 and only one strain was identical to CV‑B1. Furthermore, VP1 in the heart biopsies was detected in enterovirus‑positive cases, as revealed by RT‑PCR. Pericarditis infection was more frequent than myocarditis (P<0.05) or myopericarditis (P=0.05). The epidemiological data demonstrate that CV‑B heart infections occur mainly during autumn and winter, and young male adults are more susceptible than adolescents or adults (P<0.5). The present findings demonstrate a higher prevalence of viral heart infections, suggesting that CV‑B may significantly contribute to heart infections.

Background: Decay Accelerating Factor (DAF) and Coxsackievirus-Adenovirus Receptor (CAR) have been identified as cellular receptors for Coxsackie B viruses (CV-B). The aim of this study is to elucidate the different binding properties of CV-B serotypes and to find out if there are any amino acid changes that could be associated to the different phenotypes.Twenty clinical CV-B isolates were tested on CaCo-2 cell line using anti-DAF (BRIC216) and anti-CAR (RmcB) antibodies. CV-B3 Nancy prototype strain and a recombinant strain (Rec, CV-B3/B4) were tested in parallel. The P1 genomic region of 12 CV-B isolates from different serotypes was sequenced and the Trans-Epithelial Electrical Resistance (TEER) along with the virus growth cycle was measured., Results: Infectivity assays revealed clear differences between CV-B isolates with regard to their interactions with DAF and CAR. All tested CV-B isolates showed an absolute requirement for CAR but varied in their binding to DAF. We also reported that for some isolates of CV-B, DAF attachment was not adapted. Genetic analysis of the P1 region detected multiple differences in the deduced amino acid sequences., Conclusion: Within a given serotype, variations exist in the capacity of virus isolates to bind to specific receptors, and variants with different additional ligands may arise during infection in humans as well as in tissue culture.

Background: A West Nile (WN) fever epidemic occurred in the region of Monastir, Tunisia, between August and October 2003., Aim of the Study: We attempt to describe the epidemiology, clinical presentation, and outcome of patients with confirmed West Nile virus (WNV) infection., Methods: Three groups of specimens were prepared. One was made up of serum only (n  =  43), the other of cerebrospinal fluid (CSF) only (n  =  30), and the third group was made up of both (n  =  40). These specimens were obtained from 113 patients. A serological diagnosis and evidence of WNV genome by nested reverse-transcriptase polymerase chain reaction (nRT-PCR) and TaqMan reverse transcription-polymerase chain reaction (RT-PCR) were carried out., Results: Thirty-eight cases (33.6%) were serologically positive. Results of nRT-PCR showed a total of 10 positive cases of WNV (8.8%) detected in group 1 (n  =  1/43), group 2 (n  =  5/30), and group 3 (n  =  4/40) whereas the PCR TaqMan showed 18 positive samples (15.9%) found in group 1 (n  =  3/43), group 2 (n  =  9/30), and group 3 (n  =  6/40). All TaqMan PCR positive cases were nRT-PCR positive. In addition, four serologically probable cases were confirmed by TaqMan PCR. The attempts to isolate WNV by cell culture were unsuccessful. Considering the results of TaqMan assay and the serological diagnosis, WNV infection was confirmed in a total of 42 patients. The main clinical presentations were meningoencephalitis (40%), febrile disease (95%), and meningitis (36%). Eight patients (19%) died. The highest case-fatality rates occurred among patients aged ≧55 years. The phylogenetic analysis revealed that isolates of WNV were closely related to the Tunisian strain 1997 (PAH001) and the Israeli one (Is-98)., Conclusions: West Nile virus is a reemerging global pathogen that remains an important public health challenge in the next decade.

Virus-induced myocarditis is a common disease even in infants and young adults, but the diagnosis can be difficult according to the Dallas-criteria, which have been criticized as being too unreliable. The diagnosis has been substantially improved due to immunohistochemistry (IHC) for the detection of the VP1-capsid-protein of enterovirus as well as reversetranscriptase-polymerase chain reaction assays (RT-PCR) for viral genome detection. We report an unusual case of myocarditis in a young adult athlete whose heart disease was not clinically recognized and, thus, caused his sudden unexpected death (SUD). Histopathological investigations of heart tissue samples revealed signs of myocarditis. IHC was used to detect the VP1-capsid-protein of enterovirus. RT-PCR assays were used to detect enterovirus RNA. Enterovirus myocarditis was determined as a cause of death., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

This study aimed to evaluate the prevalence of anti-West Nile virus (WNV) IgG among two populations of Tunisian blood donors living in areas where human outbreaks of WNV have occurred. Cohorts A (Monastir) and B (Mahdia) included 742 and 102 blood donors respectively. Sera were tested by IgG ELISA test and results were confirmed by PRNT test. WNV neutralizing antibodies were detected in 32 (4.3%) and in 14 (13.7%) sera in cohorts A and B respectively. The prevalence of anti-WNV IgG was significantly higher in cohort B than in cohort A (P<0.001) and was significantly lower in females than in males (P<0.001)., (Copyright 2010 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.)

Background: Wastewater frequently has been contaminated by enteric viruses, which can cause gastroenteritis, hepatitis, and other viral diseases. Since current water treatments do not ensure their complete removal and they become contaminants of the water environment., Aim: In order to monitor and assess the prevalence and the seasonal incidence of enteric viruses contaminating wastewater, a total of 93 samples were collected from the stations of Sayada-Lamta-Bouhjar and El Frina., Methods: The purpose of this study is to establish a rapid, sensitive and specific RT-PCR method using highly conserved primers to detect enteric viruses (caliciviruses, enteroviruses and hepatitis A viruses) circulating in the area of Monastir, during the period from October 2005 to July 2006., Results: Our study shows that the caliciviruses were detected in 67.56% of the wastewater samples and present an essentially winter distribution with a specific peak in spring. The enteroviruses were detected in 35.13% of the samples tested and present a regular circulation during the year with a predominance in the summer and early fall. Finally, the presence of hepatitis A viruses was noted especially in winter in 10.81% of the wastewater samples., Conclusion: We notice that current wastewater treatment methods are sometimes not efficient to eliminate enteric viruses.