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Background: Evaluation of local Plasmodium falciparum malaria transmission has been investigated previously using the reversible catalytic model based on prevalence of antibody responses to single antigen to estimate seroconversion rates. High correlations were observed between seroconversion rates and entomological inoculation rates (EIR). However, in this model, the effects of malaria control interventions and clinical episodes on serological measurements were not assessed. This study monitors the use of antibody responses to P. falciparum crude extracts for assessing malaria transmission, compares seroconversion rates estimated from longitudinal data to those derived from cross-sectional surveys and investigates the effects of malaria control interventions on these measures in an area of declining malaria transmission. In addition, the validity of this model was evaluated by comparison with the alternative model., Methods: Five cross-sectional surveys were carried out at the end of the wet season in Dielmo, a malaria-endemic Senegalese rural area in 2000, 2002, 2008, 2010 and 2012. Antibodies against schizonts crude extract of a local P. falciparum strain adapted to culture (Pf 07/03) were measured by ELISA. Age-specific seroprevalence model was used both for cross-sectional surveys and longitudinal data (combined data of all surveys)., Results: A total of 1504 plasma samples obtained through several years follow-up of 350 subjects was used in this study. Seroconversion rates based on P. falciparum schizonts crude extract were estimated for each cross-sectional survey and were found strongly correlated with EIR. High variability between SCRs from cross-sectional and longitudinal surveys was observed. In longitudinal studies, the alternative catalytic reversible model adjusted better with serological data than the catalytic model. Clinical malaria attacks and malaria control interventions were found to have significant effect on seroconversion., Discussion: The results of the study suggested that crude extract was a good serological tool that could be used to assess the level of malaria exposure in areas where malaria transmission is declining. However, additional parameters such as clinical malaria and malaria control interventions must be taken into account for determining serological measurements for more accuracy in transmission assessment.

Background: Coordinated scaled-up malaria control interventions have substantially contributed to the dramatic decrease of malaria-related morbidity and mortality in several endemic countries, including Senegal. However, the impacts of a given malaria control intervention on vector and parasite populations, acquired immunity, and disease burden remain very poorly documented largely due to the lack of continuous surveys. This study took advantage of the sera bank established as part of the Dielmo longitudinal project to investigate the dynamics of IgG antibody responses that accompanied the epidemiological changes resulting from malaria control interventions. Schizonts crude extract of a local strain of Plasmodium falciparum (Pfsch07/03) was used in ELISA to measure and compare seroprevalence and magnitude of IgG antibody responses from 2000 to 2012., Results: The prevalence of Pfsch07/03 IgG antibody responses progressively decreased from 97.25% in 2000 to 57.3% in 2012. The prevalence of Pfsch07/03 antibodies categorized between three different age groups (<7, 7-15, and >15 years) revealed increased seroprevalence with age ranging from 47.19 to 62.67 and 89.45%, respectively in (<7, 7-15, and >15 years) old age groups. A marked drop in seroprevalence was observed after 2008 and was significant in the younger (<7 years) and intermediate (7-15 years) age groups, unlike older individuals aged >15 years (p = 1.00)., Conclusions: The study revealed a substantial contribution of all malaria control interventions to the decrease of IgG antibodies responses to Pfsch07/03 throughout prevention of human-mosquitos contacts, or reduction of parasite biomass. The present study demonstrates the wider potential of sero-epidemiological analysis in monitoring changes in malaria transmission resulting from a given malaria control intervention.

Background: Programmes of pre-elimination of malaria have been implemented in Senegal since 2010, and the burden of malaria has decreased substantially. These changes in the epidemiology should be monitored with effective tools that allow changes in patterns of transmission to be estimated. In Dielmo and Ndiop, two villages of Senegal with different malaria endemicity, infections have been followed longitudinally for 20 years, during which time there have been several control interventions leading to substantial decreases of transmission. This study aimed to compare malaria antibody responses of the inhabitants of these two villages, between 2000 and 2010, using schizont crude extracts of a local strain of P. falciparum (Pf Sch07/03)., Methods: Sera collected from inhabitants of the two villages (141 from Dielmo and 79 from Ndiop in 2000; 143 from Dielmo and 79 from Ndiop in 2010) were used to assess the prevalence of antibodies against crude schizont extracts of Pf Sch07/03. Three ages groups were defined: [5-9] yrs, [10-14] yrs and [15-19] yrs. Statistical comparisons were performed. Seroprevalence and the magnitude of antibody responses were compared between age groups, villages and periods., Results: Overall seroprevalence to P.fSch07/03 decreased between 2000 and 2010 in both villages: from 94.4% to 44.4% in Dielmo and from 74.4% to 34.6% in Ndiop. The difference between Dielmo and Ndiop was highly significant in 2000 (p<0.001) but not in 2010 (p >0.20). The decrease in seroprevalence was larger in younger (more than 40%) than older (less than 19%) inhabitants. Longitudinal monitoring of the younger group showed that seroprevalence decreased between 2000 and 2010 in Dielmo from 98.7 to 79.3, but not in Ndiop from 67.6 to 66.7. The magnitude of antibody responses in seropositive individuals was significantly higher in 2000 than 2010 for both villages., Conclusions: Crude extracts of P. falciparum are appropriate tools for evaluating malaria prevalence at different periods, and in both low and high endemic area. Using crude extracts from local strains to assess transmission may allow efficient evaluation of the consequences of control programs on malaria transmission.

Insufficient attention paid to dental arch forms during orthodontic treatment can give rise to relapses. The aim of this study was to calculate the mean dental arch form of the Senegalese subject and to suggest a characteristic polynomial function. Our sample comprised 57 Senegalese subjects aged between 13 and 33 years displaying an ideal occlusion. By superimposing all the arch curves of the different subjects in the series and by adopting intermolar distance as the standard unit, we were able to calculate the mean maxillary and mandibular arch forms and suggest a polynomial function of 6 degrees enabling production of almost perfect reproductions of these forms., (Copyright 2010 CEO. Published by Elsevier Masson SAS. All rights reserved.)

Introduction: Antiretroviral therapy has dramatically changed the natural history of HIV infection. The aim of this study was to evaluate the effectiveness and tolerance of Non Nucleosidic Reverse Trancriptase Inhibitors containing regimens in HIV-1 infection., Patients and Methods: This is a retrospective chart review of 257 HIV-1 infected patients followed in the infectious clinic ward of fann, from august 1998 to February 2002., Results: Overall 195 patients (75.87%) were on efavirenz and 62 (25.2%) on nevirapine, with a male predominance (sex-ratio = 1.44). Baseline HIV-1 viral load was higher in efavirene group (p = 0.03). The two groups were comparable for immune restoration, tolerance, rate of treatment discontinuation and letality. The viral suppression was greater in efavirenz group at month 6 (p = 0.04)., Conclusion: Non nucleosidic reverse transcriptase inhibitor containing regimens are effective and well tolerated. Those results make them suitable for first line therapy in HIV-1-infection.

Background: Previous attempts in animals failed to reproduce the metabolic, pathological, and clinical situations encountered in homocystinuric patients. Minipigs on a methionine-rich caseinate-based diet, however, have a special long-lasting postprandial plasma accumulation of methionine, the metabolic precursor of homocysteine. We hypothesized that these minipigs develop hyperhomocysteinemia in the long term. Angiotensin-converting enzyme (ACE) inhibition prevents atherogenic alteration of viscoelastic functions of arterial pulsatility and compliance and reduces fragmentation of vascular elastic laminae in the minipigs. We consequently analyzed the therapeutic effects of the captopril-hydrochlorothiazide combination against the typical hyperhomocysteinemia-induced alterations of vascular elastic features., Methods and Results: Thirty-two Götingen minipigs were randomized as control diet-fed (C), captopril (25 mg/d)/hydrochlorothiazide (12.5 mg/d)-treated C (C+Cp), caseinate-based diet-fed (M), and M+Cp minipigs. After 4 months, M and M+Cp animals had hyperhomocysteinemia (9.64 +/- 4.10 mumol/L, n = 16) compared with C and C+Cp minipigs (5.67 +/- 1.14 mumol/L, n = 16) (P < .05). In the M group, one minipig died from thromboembolic syndrome, and one had pulmonary infarction. M minipigs presented with systolic-diastolic hypertension and extended reactive hyperemia, as well as a mega-artery syndrome in hyperpulsatile arteries due to expanded volumetric compliance, curtailed stiffness, strengthened vascular tension, and prevalence of the viscous wall component. In their arterial tree, hypertrophic endothelial cells covered a thickened subendothelial space. Major elastic lamina dislocations were observed, as well as hypertrophy and reorientation of smooth muscle cells, resulting in the settlement of spreading pathways for medial cells between muscular laminae. In C+Cp and M+Cp animals, serum and lung ACE activity were inhibited by 74% and 40%, respectively. Although the treatment with captopril-hydrochlorothiazide did not modify the hyperhomocysteinemia per se, the therapeutic effects of the drug combination are made evident by the absence of death and ischemic diseases in the M+Cp group. Specifically, the drug combination prevented diastolic hypertension and improved aortic blood flow by normalizing peripheral resistances, abolished the vascular hyperpulsatile characters, and restrained the fragmentation and the splitting of elastic fibers in capacitance arteries. In contrast, the drugs slightly prevented systolic and mean hypertension. In addition, the aortic stiffness and stress response remained altered and vascular smooth muscle cell hypertrophy was still observed in the M+Cp group., Conclusions: In minipigs, the present methionine-rich caseinate-based diet induced hyperhomocysteinemia, which reproduces the metabolic and histopathological situation found in homocysteic patients. Our results show that hyperhomocysteinemia-induced vascular alterations favor the viscous component of the wall rheology to the detriment of the elastic component. Furthermore, they extend to hyperhomocysteinemia the therapeutic effects characteristically shared by ACE inhibitors in association with hydrochlorothiazide against the atherogenic activation of elastinolytic processes.

The renin angiotensin system is a negative feed-back system of blood pressure control. A number of concordant experimental and clinical results indicate that the angiotensin family has a trophic effect on the vessel wall. These properties of the angiotensins favorise the proliferation of the cells which make up the vessel wall and also amplify the vascular dysfunction in the absence of the inhibitory regulations. Angiotensin converting enzyme inhibitors could be a valuable therapeutic method of counteracting these deleterious effects on the composition and function of the vessel wall.

In order to evaluate the usefulness of B-mode ultrasonography in the diagnosis of deep vein thrombosis, a prospective study was performed on 145 patients. Each patient was examined with occlusive venous plethysmography, continuous wave Doppler, real-time B-mode ultrasonography, and radiographic contrast phlebography. The diagnostic sensitivity and specificity versus phlebography were 91 and 82.1 per cent, respectively, for plethysmography, 92 and 86.6 per cent for Doppler, and 94 and 100 per cent for B-mode sonographic scanning. The combined noninvasive approach reached a 96 per cent sensitivity. B-mode ultrasonography demonstrated a mass in eight cases, and showed a superficial venous thrombosis in four cases, among the 45 patients without deep vein thrombosis. B-mode ultrasonography, therefore, appears to be very useful in obtaining a better specificity and differential diagnosis.

The sonographic diagnosis of deep venous thrombosis must be made up of a functional continuous wave Doppler study of the whole deep venous system of the limbs, including leg veins, as well as saphenous veins. Then, high resolution B-mode real time sonography is used for the detection of direct (echogenic thrombus) or indirect (incompressible vein) signs of thrombosis. This noninvasive approach offers a good sensitivity (about 96%) and a high level of specificity (about 98%). Moreover, B-mode sonography can ensure the differential diagnosis (hematoma, extrinsic compression...) in most cases. So, X-Ray venography is required only when an interventional therapy is planned (thrombectomy, fibrinolysis, inferior vena cava interruption...), or when the noninvasive techniques are not able to show the upper limit of the thrombosis (especially for iliac veins or inferior vena cava), or when there is still a doubt about deep venous thrombosis. Therefore, the number of X Ray venographies can be consistently reduced, thus decreasing both cost and risks.