86 research outputs found
An Analysis of CS Tear Gas Deployment with Respect to Space, Time and Concentration
Investigates the prevalence of CS tear gas use in departments and whether data is gathered on the amount of gas used
Conversation: Design + ethics: How is it more than the sum of its parts?
The discussion of ethics in design has so far relied on theories and approaches from other disciplines. We argue that design can benefit from an explicit discussion on the ethics of its methods and practices that arises from within the discipline. This Conversation aimed at stimulating this discussion. Around 25 people attended in person, in addition to the online participants. We asked our audience about the main approaches they use for ethical inquiry and discussed the opportunities and challenges of applying these. We found out that ethics may best be framed as an invitation to care, without reducing it to a checklist, toolkit or an
afterthought that can be added onto the design process. Although the situated nature of ethical issues calls for a plurality of approaches, we foresee boundaries to pluralism that acknowledge historical legacies of violence. Hence, we see a role for design to willingly engage with problematizing (vs. problem-solving) when addressing societal issues, with a view towards structural injustices
Rifampicin/Cotrimoxazole/Isoniazid Versus Mefloquine or Quinine + Sulfadoxine- Pyrimethamine for Malaria: A Randomized Trial
OBJECTIVES: Previous studies of a fixed combination including cotrimoxazole, rifampicin, and isoniazid (Cotrifazid) showed efficacy against resistant strains of Plasmodium falciparum in animal models and in small-scale human studies. We conducted a multicentric noninferiority trial to assess the safety and efficacy of Cotrifazid against drug-resistant malaria in Papua New Guinea. DESIGN: The trial design was open-label, block-randomised, comparative, and multicentric. SETTING: The trial was conducted in four primary care health facilities, two in urban and two in rural areas of Madang and East Sepik Province, Papua New Guinea. PARTICIPANTS: Patients of all ages with recurrent uncomplicated malaria were included. INTERVENTIONS: Patients were randomly assigned to receive Cotrifazid, mefloquine, or the standard treatment of quinine with sulfadoxine–pyrimethamine (SP). OUTCOME MEASURES: Incidence of clinical and laboratory adverse events and rate of clinical and/or parasitological failure at day 14 were recorded. RESULTS: The safety analysis population included 123 patients assigned to Cotrifazid, 123 to mefloquine, and 123 to quinine + SP. The Cotrifazid group experienced lower overall incidence of adverse events than the other groups. Among the efficacy analysis population (72 Cotrifazid, 71 mefloquine, and 75 quinine + SP), clinical failure rate (symptoms and parasite load) on day 14 was equivalent for the three groups (0% for Cotrifazid and mefloquine; 1% for quinine + SP), but parasitological failure rate (P. falciparum asexual blood-stage) was higher for Cotrifazid than for mefloquine or quinine + SP (9% [PCR corrected 8%] versus 0% and 3%, respectively [p = 0.02]). CONCLUSION: Despite what appears to be short-term clinical equivalence, the notable parasitological failure at day 14 in both P. falciparum and P. vivax makes Cotrifazid in its current formulation and regimen a poor alternative combination therapy for malaria
Angiotensin converting enzyme inhibitor therapy in children with Alport syndrome: effect on urinary albumin, TGF-β, and nitrite excretion
BACKGROUND: Angiotensin converting enzyme inhibitors are routinely prescribed to patients with chronic kidney disease because of their known renoprotective effects. We evaluated the effect of short-term therapy with the angiotensin converting enzyme inhibitor, enalapril, in early Alport syndrome, defined as disease duration less than 10 years and a normal glomerular filtration rate. METHODS: 11 children with early Alport syndrome were investigated. Two consecutive early morning urine specimens were collected at the start of the study for measurement of urinary creatinine, total protein, albumin, TGF-β, and nitrite excretion. Patients were treated with enalapril, ≅ 0.2 mg/kg/day, once a day for 14 days. Two early morning urine specimens were collected on days 13 and 14 of enalapril treatment and two weeks later for measurement of urinary creatinine, total protein, albumin, TGF-β, and nitrite excretion. RESULTS: Prior to treatment, urinary excretion of transforming growth factor-β and nitrite, the major metabolite of nitric oxide, was within normal limits in all patients. Administration of enalapril for 2 weeks did not alter urinary albumin, transforming growth factor-β, or nitrite excretion. CONCLUSION: These findings suggest that early Alport syndrome represents a disease involving exclusively intrinsic glomerular barrier dysfunction. At this stage of the illness, there is no evidence of angiotensin II-mediated proteinuria or increased production of transforming growth factor-β and, therefore, routine treatment with an angiotensin converting enzyme inhibitor may not be warranted
Combined chloroquine, sulfadoxine/pyrimethamine and primaquine against Plasmodium falciparum in Central Java, Indonesia
BACKGROUND: Chloroquine (CQ) or sulfadoxine-pyrimethamine (SP) monotherapy for Plasmodium falciparum often leads to therapeutic failure in Indonesia. Combining CQ with other drugs, like SP, may provide an affordable, available and effective option where artemisinin-combined therapies (ACT) are not licensed or are unavailable. METHODS: This study compared CQ (n = 29 subjects) versus CQ + SP (with or without primaquine; n = 88) for clinical and parasitological cure of uncomplicated falciparum malaria in the Menoreh Hills region of southern Central Java, Indonesia. Gametocyte clearance rates were measured with (n = 56 subjects) and without (n = 61) a single 45 mg dose of primaquine (PQ). RESULTS: After 28 days, 58% of subjects receiving CQ had cleared parasitaemia and remained aparasitaemic, compared to 94% receiving CQ combined with SP (p < 0.001). Msp-2 genotyping permitted reinfection-adjusted cure rates for CQ and CQ combined with SP, 70% and 99%, respectively (p = 0.0006). CONCLUSION: Primaquine exerted no apparent affect on cure of asexual stage parasitaemia, but clearly accelerated clearance of gametocytes. CQ combined with SP was safe and well-tolerated with superior efficacy over CQ for P. falciparum parasitaemia in this study
A New Malaria Agent in African Hominids
Plasmodium falciparum is the major human malaria agent responsible for 200 to 300 million infections and one to three million deaths annually, mainly among African infants. The origin and evolution of this pathogen within the human lineage is still unresolved. A single species, P. reichenowi, which infects chimpanzees, is known to be a close sister lineage of P. falciparum. Here we report the discovery of a new Plasmodium species infecting Hominids. This new species has been isolated in two chimpanzees (Pan troglodytes) kept as pets by villagers in Gabon (Africa). Analysis of its complete mitochondrial genome (5529 nucleotides including Cyt b, Cox I and Cox III genes) reveals an older divergence of this lineage from the clade that includes P. falciparum and P. reichenowi (∼21±9 Myrs ago using Bayesian methods and considering that the divergence between P. falciparum and P. reichenowi occurred 4 to 7 million years ago as generally considered in the literature). This time frame would be congruent with the radiation of hominoids, suggesting that this Plasmodium lineage might have been present in early hominoids and that they may both have experienced a simultaneous diversification. Investigation of the nuclear genome of this new species will further the understanding of the genetic adaptations of P. falciparum to humans. The risk of transfer and emergence of this new species in humans must be now seriously considered given that it was found in two chimpanzees living in contact with humans and its close relatedness to the most virulent agent of malaria
Confirmation of emergence of mutations associated with atovaquone-proguanil resistance in unexposed Plasmodium falciparum isolates from Africa
BACKGROUND: In vitro and in vivo resistance of Plasmodium falciparum to atovaquone or atovaquone-proguanil hydrochloride combination has been associated to two point mutations in the parasite cytochrome b (cytb) gene (Tyr268Ser and Tyr268Asn). However, little is known about the prevalence of codon-268 mutations in natural populations of P. falciparum without previous exposure to the drug in Africa. METHODS: The prevalence of codon-268 mutations in the cytb gene of African P. falciparum isolates from Nigeria, Malawi and Senegal, where atovaquone-proguanil has not been introduced for treatment of malaria was assessed. Genotyping of the cytb gene in isolates of P. falciparum was performed by PCR-restriction fragment length polymorphism and confirmed by sequencing. RESULTS: 295 samples from Nigeria (111), Malawi (91) and Senegal (93) were successfully analyzed for detection of either mutant Tyr268Ser or Tyr268Asn. No case of Ser268 or Asn268 was detected in cytb gene of parasites from Malawi or Senegal. However, Asn268 was detected in five out of 111 (4.5%) unexposed P. falciparum isolates from Nigeria. In addition, one out of these five mutant Asn268 isolates showed an additional cytb mutation leading to a Pro266Thr substitution inside the ubiquinone reduction site. CONCLUSION: No Tyr268Ser mutation is found in cytb of P. falciparum isolates from Nigeria, Malawi or Senegal. This study reports for the first time cytb Tyr268Asn mutation in unexposed P. falciparum isolates from Nigeria. The emergence in Africa of P. falciparum isolates with cytb Tyr268Asn mutation is a matter of serious concern. Continuous monitoring of atovaquone-proguanil resistant P. falciparum in Africa is warranted for the rational use of this new antimalarial drug, especially in non-immune travelers
Plasmodium chabaudi chabaudi malaria parasites can develop stable resistance to atovaquone with a mutation in the cytochrome b gene
<p>Abstract</p> <p>Background</p> <p><it>Plasmodium falciparum</it>, has developed resistance to many of the drugs in use. The recommended treatment policy is now to use drug combinations. The atovaquone-proguanil (AP) drug combination, is one of the treatment and prophylaxis options. Atovaquone (ATQ) exerts its action by inhibiting plasmodial mitochondria electron transport at the level of the cytochrome bc1 complex. <it>Plasmodium falciparum in vitro </it>resistance to ATQ has been associated with specific point mutations in the region spanning codons 271-284 of the <it>cytochrome b </it>gene. ATQ -resistant <it>Plasmodium yoelii </it>and <it>Plasmodium berghei </it>lines have been obtained and resistant lines have amino acid mutations in their CYT <it>b </it>protein sequences. <it>Plasmodium chabaudi </it>model for studying drug-responses and drug-resistance selection is a very useful rodent malaria model but no ATQ resistant parasites have been reported so far. The aim of this study was to determine the ATQ sensitivity of the <it>P. chabaudi </it>clones, to select a resistant parasite line and to perform genotypic characterization of the <it>cytb </it>gene of these clones.</p> <p>Methods</p> <p>To select for ATQ resistance, <it>Plasmodium. chabaudi chabaudi </it>clones were exposed to gradually increasing concentrations of ATQ during several consecutive passages in mice. <it>Plasmodium chabaudi cytb </it>gene was amplified and sequenced.</p> <p>Results</p> <p>ATQ resistance was selected from the clone AS-3CQ. In order to confirm whether an heritable genetic mutation underlies the response of AS-ATQ to ATQ, the stability of the drug resistance phenotype in this clone was evaluated by measuring drug responses after (i) multiple blood passages in the absence of the drug, (ii) freeze/thawing of parasites in liquid nitrogen and (iii) transmission through a mosquito host, <it>Anopheles stephensi</it>. ATQ resistance phenotype of the drug-selected parasite clone kept unaltered. Therefore, ATQ resistance in clone AS-ATQ is genetically encoded. The Minimum Curative Dose of AS-ATQ showed a six-fold increase in MCD to ATQ relative to AS-3CQ.</p> <p>Conclusions</p> <p>A mutation was found on the <it>P. chabaudi cytb </it>gene from the AS-ATQ sample a substitution at the residue Tyr268 for an Asn, this mutation is homologous to the one found in <it>P. falciparum </it>isolates resistant to ATQ.</p
Active case detection, treatment of falciparum malaria with combined chloroquine and sulphadoxine/pyrimethamine and vivax malaria with chloroquine and molecular markers of anti-malarial resistance in the Republic of Vanuatu
<p>Abstract</p> <p>Background</p> <p>Chloroquine-resistant <it>Plasmodium falciparum </it>was first described in the Republic of Vanuatu in the early 1980s. In 1991, the Vanuatu Ministry of Health instituted new treatment guidelines for uncomplicated <it>P. falciparum </it>infection consisting of chloroquine/sulphadoxine-pyrimethamine combination therapy. Chloroquine remains the recommended treatment for <it>Plasmodium vivax</it>.</p> <p>Methods</p> <p>In 2005, cross-sectional blood surveys at 45 sites on Malo Island were conducted and 4,060 adults and children screened for malaria. Of those screened, 203 volunteer study subjects without malaria at the time of screening were followed for 13 weeks to observe peak seasonal incidence of infection. Another 54 subjects with malaria were followed over a 28-day period to determine efficacy of anti-malarial therapy; chloroquine alone for <it>P. vivax </it>and chloroquine/sulphadoxine-pyrimethamine for <it>P. falciparum </it>infections.</p> <p>Results</p> <p>The overall prevalence of parasitaemia by mass blood screening was 6%, equally divided between <it>P. falciparum </it>and <it>P. vivax</it>. Twenty percent and 23% of participants with patent <it>P. vivax </it>and <it>P. falciparum </it>parasitaemia, respectively, were febrile at the time of screening. In the incidence study cohort, after 2,303 person-weeks of follow-up, the incidence density of malaria was 1.3 cases per person-year with <it>P. vivax </it>predominating. Among individuals participating in the clinical trial, the 28-day chloroquine <it>P. vivax </it>cure rate was 100%. The 28-day chloroquine/sulphadoxine-pyrimethamine <it>P. falciparum </it>cure rate was 97%. The single treatment failure, confirmed by <it>merozoite surface protein-2 </it>genotyping, was classified as a day 28 late parasitological treatment failure. All <it>P. falciparum </it>isolates carried the Thr-76 <it>pfcrt </it>mutant allele and the double Asn-108 + Arg-59 <it>dhfr </it>mutant alleles. <it>Dhps </it>mutant alleles were not detected in the study sample.</p> <p>Conclusion</p> <p>Peak seasonal malaria prevalence on Malo Island reached hypoendemic levels during the study observation period. The only <it>in vivo </it>malaria drug efficacy trial thus far published from the Republic of Vanuatu showed chloroquine/sulphadoxine-pyrimethamine combination therapy for <it>P. falciparum </it>and chloroquine alone for <it>P. vivax </it>to be highly efficacious. Although the chloroquine-resistant <it>pfcrt </it>allele was present in all <it>P. falciparum </it>isolates, mutant alleles in the <it>dhfr </it>and <it>dhps </it>genes do not yet occur to the extent required to confer sulphadoxine-pyrimethamine resistance in this population.</p
Efficacy of artemether-lumefantrine, the nationally-recommended artemisinin combination for the treatment of uncomplicated falciparum malaria, in southern Laos
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