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Abstract: In this paper we developed an entirely new and highly sensitive luminol–H2O2 flow injection chemiluminescence system using the enhancement effect of CdTe quantum dots–IgG bioconjugates. Immunoglobulin G (IgG) as a kind of bio-molecule was conjugated to different sized CdTe semiconductor quantum dots (QDs). Using PL spectra and CL intensity profiles, it was found that chemiluminescence resonance energy transfer (CRET) was possibly occurring between CdTe–IgG bioconjugate and luminol. Under optimum conditions, increase of IgG concentration in CdTe–IgG bioconjugate resulted enhancing effect on CL intensity of luminol–H2O2 system. Moreover quenching effects on CL intensity by addition of different proteases can construct turn off biosensor for these proteases with low detection limits and wide linear range. Furthermore, the effects of various organic and inorganic species on CdTe–IgG bioconjugates enhanced luminol–H2O2 CL system were also studied in this paper. [Copyright &y& Elsevier]

Pb (II)‐imprinted superparamagnetic mesoporous silica (SPMS) adsorbent has been synthesized and characterized. The thiol functionalized SPMS offered a fast adsorption kinetics for Pb(II) and equilibrium was achieved in just 20 min at pH 8.0. The adsorption isotherm data fits well with Langmuir model with a maximum adsorption capacity of 377.36 mg g−1. The selectivity co‐efficients of imprinted adsorbent for Pb(II)/Cu(II) and Pb(II)/Bi(III) were 3.36 and 3.05 times higher than that of non‐imprinted adsorbent. The imprinted adsorbent was employed for the solid phase extraction of Pb(II) and its detection by graphite furnace atomic absorption spectrometry (GFAAS).The parameters affecting the determination of Pb(II) were also well investigated and optimized. A linear relationship between the Pb(II) concentration and the absorbance was found in the range of 0.8‐500 ng mL−1 with a detection limit of 0.25 ng mL−1. The imprinted adsorbent was applied to the determination of Pb(II) in two certified sediment samples with satisfactory results, which indicates that Pb(II)‐imprinted superparamagnetic mesoporous silica adsorbent possess promising features of a viable adsorbent for the preconcentration of Pb(II) ions in complex matrices. A highly selective ion‐imprinted mesoporous silica sorbent has been prepared for extraction and preconcentration of Pb(II) from sediments. The specific recognition sites on the sorbent acted a lock and key system and increased its selectivity for Pb(II) over other co‐existing ions. The imprinted sorbent achieved faster adsorption and exhibited higher adsorption capacity as compared to its non‐imprinted analogue. [ABSTRACT FROM AUTHOR]

Background: Plasmodium falciparum resistance to artemisinin has been reported in South-East Asia. Long half-life drugs are increasingly being used for malaria prevention. The potential spread of parasite resistance to these regimens is real and makes regular efficacy surveillance a priority. Methods: From August to December 2004 and July to December 2005, a randomized open label trial of sulphadoxinepyrimethamine (SP) + artesunate (AS) versus SP + amodiaquine (AQ), and SP alone, was conducted in two villages of Mali. PCR was used to distinguish new infections from recrudescent P. falciparum infections. Patients were followed for 28 days to assess treatment efficacy. Results: Overall 912 children aged between six to 59 months, with uncomplicated P. falciparum malaria were recruited. Baseline characteristics were similar in the three treatment arms. Crude ACPRs were 94.9%; 98.6% and 93.5% for SP + AS; SP + AQ and SP alone arms respectively (SP + AS versus SP + AQ, p = 0.01; SP + AS versus SP, p = 0.5; SP + AQ versus SP, p = 0.001). After PCR adjustment, cACPRs were 99%; 100% and 97.2% for SP + AS; SP + AQ and SP alone arms, respectively (SP + AS versus SP + AQ, p = 0.25; SP + AS versus SP, p = 0.12; SP + AQ versus SP, p = 0.007). Conclusion: Sulphadoxine-pyrimethamine + amodiaquine therapy was as efficacious as sulphadoxinepyrimethamine + artesunate, but more efficacious than sulphadoxine-pyrimethamine alone in the treatment of uncomplicated P. falciparum malaria in Mali. [ABSTRACT FROM AUTHOR]

The article discusses the need of the needs of biomedical science training in Africa. To conduct the survey of the region, a total of 107 young scientists were recruited through existing international networks and interviewed via a web-based program, on the current status of biomedical research in their different institutions. Information on the obstacles for biomedical science research which include the lack of infrastructure and financial support from government is presented.

Objective To assess the efficacy of intermittent preventive treatment (IPT) against malaria in school-aged children. Methods This was an open randomized controlled trial of seasonal IPT among school children (IPTsc) aged 6–13 years in Kollé, Mali. The study began in September 2007 and completed follow-up in May 2008. Students were randomized to one of three study arms: Sulfadoxine–pyrimethamine plus artesunate (SP/AS), amodiaquine plus artesunate (AQ/AS) or vitamin C. All students received two full treatment doses, given 2 months apart during the season of high transmission from September to December. Groups were compared with respect to incidence of clinical malaria, asymptomatic parasitemia and haemoglobin concentration. Results A total of 296 students were randomized, and retention in the study was 99.3%. Clinical malaria incidence in the SP/AS and AQ/AS arms was reduced by 66.6% and 46.5%, respectively, vs. vitamin C ( P < 0.001). There were fewer clinic visits for any cause among the children receiving SP/AS or AQ/AS ( P = 0.024). The prevalence of asymptomatic parasitemia was fivefold higher in the vitamin C arm than either SP/AS or AQ/AS at each post-treatment evaluation ( P < 0.001). At the end of the transmission period, children treated with IPT had lower rates of anaemia (SP/AS, 17.7%; AQ/AS, 16.0%; vitamin C, 29.6%; P = 0.039). Conclusion IPT among school children reduced the rates of clinical malaria, all-cause acute clinic visits, asymptomatic parasitemia and anaemia among school-aged children. [ABSTRACT FROM AUTHOR]

Background: Artemether-lumefantrine is a highly effective artemisinin-based combination therapy that was adopted in Mali as first-line treatment for uncomplicated Plasmodium falciparum malaria. This study was designed to measure the efficacy of artemether-lumefantrine and to assess the selection of the P. falciparum chloroquine resistance transporter (pfcrt) and P. falciparum multi-drug resistance 1 (pfmdr1) genotypes that have been associated with drug resistance. Methods: A 28-day follow-up efficacy trial of artemether-lumefantrine was conducted in patients aged 6 months and older suffering from uncomplicated falciparum malaria in four different Malian areas during the 2009 malaria transmission season. The polymorphic genetic markers MSP2, MSP1, and Ca1 were used to distinguish between recrudescence and reinfection. Reinfection and recrudescence were then grouped as recurrent infections and analyzed together by PCR-restriction fragment length polymorphism (RFLP) to identify candidate markers for artemether-lumefantrine tolerance in the P. falciparum chloroquine resistance transporter (pfcrt) gene and the P. falciparum multi-drug resistance 1 (pfmdr1) gene. Results: Clinical outcomes in 326 patients (96.7%) were analyzed and the 28-day uncorrected adequate clinical and parasitological response (ACPR) rate was 73.9%. The total PCR-corrected 28-day ACPR was 97.2%. The pfcrt 76T and pfmdr1 86Y population prevalence decreased from 49.3% and 11.0% at baseline (n = 337) to 38.8% and 0% in patients with recurrent infection (n = 85); p = 0.001), respectively. Conclusion: Parasite populations exposed to artemether-lumefantrine in this study were selected toward chloroquine-sensitivity and showed a promising trend that may warrant future targeted reintroduction of chloroquine or/and amodiaquine. [ABSTRACT FROM AUTHOR]