Counterfeit and substandard antimalarial drugs can cause death and contribute to the growing malaria drug resistance problem, particularly in Southeast Asia. Since 2003 in Cambodia the quality of ...antimalarial drugs both in the public and private health sector is regularly monitored in sentinel sites. We surveyed 34% of all 498 known facilities and drug outlets in four provinces. We collected 451 drug samples; 79% of these were not registered at the Cambodia Department of Drugs and Food (DDF). Twenty-seven percent of the samples failed the thin layer chromatography and disintegration tests; all of them were unregistered products. Immediate action against counterfeit drugs was taken by the National Malaria Control Program (NMCP) and the DDF. They communicated with the Provincial Health Department about the presence of counterfeit antimalarial drugs through alert letters, a manual, annual malaria conferencing and other training occasions. Television campaigns to alert the population about counterfeit drugs were conducted. Moreover, the NMCP has been promoting the use of good quality antimalarial drugs of a blister co-packaged combination of artesunate and mefloquine in public and private sectors. Appropriate strategies need to be developed and implemented by relevant government agencies and stakeholders to strengthen drug quality assurance and control systems in the country.
Despite its diminishing efficacy because of increased resistance, chloroquine remains the primary antimalarial agent in many endemic areas. Evidence is mounting that point mutations on the Pfcrt and ...possibly the Pfmdr1 genes are conferring plasmodial resistance to chloroquine. In 1998, atypically strong rainfalls led to an increased activity of falciparum malaria in Mauritania that affected non-endemic regions bordering the Saharan desert. An in vivo study on chloroqine resistance was combined with studies for molecular markers of drug resistance. Detection of Pfmdr1-76-tyrosine showed an increased odds ratio (2.91) for resistance (P = 0.0195). However, by use of this codon alone, sensitivity for detection of resistance was 60.6%, and specificity was 65.3%. In comparison, detection of the K76T mutation at Pfcrt showed a very high sensitivity (100%) while specificity remained relatively low (65.4%). For the combination of mutations on both genes, the odds ratio for detection of resistance increased to 5.31 (P = 0.0005). Here, sensitivity was again decreased to 60.6% while specificity increased to 76.9%. The results of this study suggest that detection of Pfcrt T76 can be applied for predicting chloroquine resistance in epidemiologic settings with sufficiently high sensitivity to make it an attractive alternative to time- and labor-consuming in vivo trials. Additional testing for Pfmdr Y76 provides increased specificity to this approach.
The prevalence of dengue antibodies was determined in the Attapeu region of South Laos with 225 blood samples collected from mostly febrile patients during the rainy season August − October 2001. An ...IgM capture ELISA was positive for one (0.4%) sample, while 177 (79%) samples were positive in an indirect IgG ELISA. Of the positive IgG samples, 20 (11.3%) were also positive on blood slides for Plasmodium falciparum. Dengue fever seems to be widespread in this area, but clinical dengue diagnosis remains difficult, especially in the first days of illness when physicians have to discriminate between dengue and other febrile illnesses.
Arising from: R. W. Snow, C. A. Guerra, A. M. Noor, H. Y. Myint & S. I. Hay Nature 434, 214-217 (2005); see also communication from Nahlen; Snow et al. reply.Accurate estimates of the global burden ...of malaria are important for planning, monitoring and advocacy. Snow et al. attempt to address the shortcomings of previous estimates of the incidence of malaria caused by Plasmodium falciparum by combining current and historical data. However, we believe that the design of their model and its inputs have led to a significant overestimate of the malaria burden outside Africa - as in the example of the World Health Organization (WHO) western Pacific region (WPR), for which their model predicts 60 times the 2002 incidence reported by national malaria-control programmes.
While the population structure of Plasmodium falciparum is well analysed in selected areas with high malaria endemicity in East and West Africa, only limited data are available for low endemicity ...regions bordering the Saharan desert. This is one of the first studies for the Sahel, where atypically strong rainfalls in 1998 and 1999 led to a severe outbreak of falciparum malaria in south‐east Mauritania. During a study on in vivo‐drug resistance against chloroquine we collected blood samples of patients with fever in two medical centres located in non‐endemic and hypoendemic areas. We analysed 386 samples by polymerase chain reaction for infection with P. falciparum, and 173 (45%) tested positive. The isolates were genotyped for three polymorphic genetic markers: merozoite surface protein 1 (MSP1), MSP2 and glutamate‐rich protein (GLURP). Differences between the two regions could be shown in either number of clones per infection or in their distribution on the different allelic groups. While the mean minimal number of clones in the non‐endemic region around Aioun was 1.57, blood samples collected in the hypoendemic region around Kobeni showed multiple infections with an average of 2.34 clones (P < 0.001). In addition, clear differences between endemic regions were apparent in three of the investigated allelic groups: RO33 of the MSP1 gene and FC and Indochina of the MSP2 gene.
The increasing resistance of Plasmodium falciparum in the treatment of uncomplicated malaria with pyrimethamine/sulphadoxine has been associated in several studies with the occurrence of point ...mutations in the genes of dihydrofolate reductase (DHFR) and dihydropteroate synthetase (DHPS). In this study, the prevalence of these mutations was examined in samples from south‐east Mauritania, where atypically strong rainfalls in 1998 and 1999 led to a severe outbreak of falciparum malaria. We analysed 386 samples by polymerase chain reaction (PCR) for infection with P. falciparum, of which 162 (41.97%) were positive. These isolates were examined for point mutations in the genes of DHFR (codons 16, 51, 59, 108 and 164) and DHPS (codons 436, 437, 540, 581 and 613) by nested PCR and subsequent mutation‐specific restriction enzyme digest. We found a low overall prevalence of DHFR gene mutations (up to 18.6% of isolates), but a high overall prevalence of DHPS gene mutations (up to 49.1% of isolates). Thus, emerging resistance to antifolate drugs may be expected to develop soon in the investigated area. This study demonstrates the utility of simple, relatively rapid and inexpensive molecular methods and their application in surveillance programmes. Testing for prevalence of point mutations conferring antifolate resistance might help to identify the developing of drug resistance at a very early stage.
National disease burdens are often not estimated at all or are estimated using inaccurate methods, partly because the data sources for assessing disease burden-nationally representative household ...surveys, demographic surveillance sites, and routine health information systems-each have their limitations. An important step forward would be a more consistent quantification of the population at risk of malaria. This is most likely to be achieved by delimiting the geographical distribution of malaria transmission using routinely collected data on confirmed cases of disease. However, before routinely collected data can be used to assess trends in the incidence of clinical cases and deaths, the incompleteness of reporting and variation in the utilization of the health system must be taken into account. In the future, sentinel surveillance from public and private health facilities, selected according to risk stratification, combined with occasional household surveys and other population-based methods of surveillance, may provide better assessments of malaria trends.
The Americans with Disabilities Act requires that covered entities provide a substantially equivalent experience to that of able-bodied persons. However, the Seventh Circuit, recently applied a but ...for test for a para-ambulatory high school athlete's reasonable accommodation request, and denied this request. This Note argues that the Seventh Circuit should have used a two-part meaningful access test, which should be informed by past legislation based on discrimination as a result of physiological differences. To ensure that para-ambulatory student athletes have the opportunity to participate in high school sports, a separate division or qualifying times must be created.
The micro-gap wire chamber Christophel, E.; Dracos, M.
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/1997, Letnik:
398, Številka:
2
Journal Article
Recenzirano
A new gas chamber configuration is described. It combines the geometry of the classical multiwire proportional chambers and one of the recently developed micro-gap chambers. These new chambers ...consist of a cathode and an anode wire plane separated by thin dielectric strips. The anode shape restores the cylindrical electric field configuration of the multiwire proportional chambers lost by the micro-gap chambers due to their flat anode shape. Gas gains higher than 10
5 have been obtained under stable conditions allowing the detection of single electrons. Using a current preamplifier, fast and short signals have been observed.
The micro gap wire chambers and their electronics Christophel, E; Dracos, M; Strub, R
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2000, Letnik:
454, Številka:
1
Journal Article
Recenzirano
The Micro Gap Wire Chambers (MGWC) proposed as tracking detectors are very compact wire chambers. They provide a 2D readout by reading the anode wires and the cathode strips. A very important ...parameter is the anode–cathode coupling which must be as high as possible to have comparable efficiency in both coordinate reconstructions. Using a 50μm kapton substrate, an anode–cathode coupling higher than 95% was obtained. Short-signal rise time (<2ns) and width (<20ns) were also observed. To take advantage of these parameters a fast transimpedance amplifier (F–TRIA99) has been constructed. The first results obtained using this amplifier are also presented.
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