14.04.2008
80,000 die from malaria in Pakistan every year [The Post - Lahore,Punjab,Pakistan] — (English)
According to health experts, despite spending billions of rupees to eradicate malaria through the rollback malaria strategy, the disease and its vector flourish in the country. They said that there was an urgent need on part of the government to reassess the growing incidence of the disease across the country...
13.04.2008
World Benefit at UCR to help fight malaria [Press-Enterprise - Riverside,CA,USA] — (English)
World Benefit, a festival to support global efforts to fight malaria, will be held at UC Riverside on Tuesday...
Festival to Aid Fight Against Malaria [UC Riverside - Riverside,CA,USA] — (English)
UC Riverside students will support global efforts to fight malaria with World Benefit, a festival on Tuesday, April 15, that will raise money for UNICEF’s Roll Back Malaria campaign...
17 million mosquito nets to be distributed [New Vision - Kampala,Uganda] — (English)
The Government will distribute over 17 million free mosquito nets, the health minister has said...
12.04.2008
Malaria: Scientists ask 'where is all the money going given rising deaths?' [Africa Science News Service - Nairobi,Kenya] — (English)
A new study in the April issue of the American Journal of Tropical Medicine and Hygiene, asks the question “With more than $220 million dollars dedicated to malaria treatment and prevention, why is the annual mortality rate from malaria on the rise?" ...
View the abstract in the previous issue of MITN
Sénégal: 20.000 moustiquaires distribuées à Mbour [Le Soleil (Dakar) via allAfrica.com] — (Français)
Le Projet Ccf Cama Prn Mbour a procédé, le 25 mars dernier, au lancement de la distribution gratuite de 20.000 moustiquaires imprégnées aux enfants de 0 à 59 mois. Une manifestation qui s'inscrit dans le cadre de la lutte contre le paludisme...
Sénégal: Une trentaine de vaccins sont à des niveaux variables de développement [Le Soleil (Dakar) via allAfrica.com] — (Français)
"Vaccin contre le paludisme, ou en est-on " Tel est le thème de la conférence animée par le docteur François Trape qui a fait savoir que tous les vaccins en expérimentation n'ont pas encore prouvé une efficacité leur autorisant d'être mis sur le marché...
Centre, northwest highly prone to malaria epidemic [Viet Nam News - Hanoi,Vietnam] — (English)
Alarms were issued over a potential malaria epidemic returning to Viet Nam by the National Institute of Malariology, Parasitology and Tomology’s director, Nguyen Manh Hung, on Thursday...
VND 145 billion to fight against malaria [Nhan Dan - Hanoi,Vietnam] — (English)
A total of VND 145 billion (US $9.06 million) will be doled out for the fight against malaria in 2008, the Ministry of Public Health announced...
11.04.2008
Clinical uncomplicated Plasmodium falciparum malaria with high schizontaemia: A case report [7thSpace Interactive (press release) - New York,NY,USA] — (English)
The treatment options for acute Plasmodium falciparum malaria are based on the clinician classifying the patient as uncomplicated or severe according to the clinical and parasitological findings. This process is not always straightforward...
Students take stand against malaria [Dubuque Telegraph Herald - Dubuque,IA,USA] — (English)
Students raise money to buy insecticide-treated nets for Nigerians...
Botswana: Malaria Epidemic Likely This Year, MoH Warns [Mmegi/The Reporter (Gaborone) via allAfrica.com] — (English)
The Ministry of Health (MoH) says Botswana has a higher probability of experiencing a malaria epidemic this year as a result of the high rainfall the country has received so far...
Clinical uncomplicated Plasmodium falciparum malaria with high schizontaemia: A case report [Malaria Journal 2008, 7:57 (11 April 2008)] — (English)
Because of sequestration, the blood film sometimes gives a poor estimate of total parasite biomass. The presence of schizonts in the peripheral circulation is warning signal that the patient requires close supervision and prompt treatment...
Nigeria: Cuba to Partner Oyo on Malaria Control [Vanguard (Lagos) via allAfrica.com] — (English)
CUBAN government has stated its readiness to partner the Otunba Adebayo Alao-Akala government of Oyo State to rid the state of malaria...
Zimbabwe: Beitbridge Hit By Malaria Outbreak [The Herald (Harare) via allAfrica.com] — (English)
Beitbridge district has been hit by a serious malaria outbreak which has so far killed 10 people in the western part of the border town, an official has said...
10.04.2008
One quick shot may not be enough [Economist - UK] — (English)
IT USUALLY takes a long time to draw the attention of voters and politicians in the rich world to a humanitarian or medical problem whose victims are mostly poor. But every so often, one of those previously neglected issues breaks through to the point where it can no longer be ignored by the rich and powerful....
Huambo: Malaria claims over 1,000 lives [ReliefWeb (press release) - Geneva,Switzerland] — (English)
At least 1,758 people died of malaria in 2007 in different health units of the central Huambo province, said a source with the institution...
More Global Warming Nonsense [WSJ - USA] — (English)
Today, the Senate Health, Education, Labor and Pensions Committee will hold a hearing on the implications of climate change for human health. Malaria will top the menu, but so will ignorance and disinformation...
Mavericks fight malaria [Dallas Weekly - USA] — (English)
Dallas Mavericks’ DeSagana Diop, United Nations and ExxonMobil Foundation join forces to fight malaria in African nations...
9.04.2008
Africa: Rolling Back Malaria [allAfrica.com] — (English)
One of the goals of the Roll Back Malaria (RBM) Partnership – launched in 1998 by the World Health Organization, the United Nations Children's Fund (Unicef), the UN Development Program (UNDP) and the World Bank – is to mark 2015 as the year in which malaria is eliminated as a major cause of mortality and as a barrier to social and economic development growth anywhere in the world. AllAfrica's Cindy Shiner asked Dr. Awa Marie Coll-Seck, executive director of the partnership, about its campaign...
Africa: On a Roll Against Malaria [allAfrica.com] — (English)
"Today we are starting to see success stories," says Awa Marie Coll-Seck, RBM's Senegalese-born executive director. "Some countries went from two percent of coverage for long-lasting [treated] bed nets to 80 percent today… [In others] we also have [malaria-related] morbidity going down, mortality going down."...
PM promises action on malaria [10 Downing Street (press release) - UK] — (English)
Gordon Brown has announced that Britain will provide 20 million extra bed nets to help in the fight against malaria - one sixth of the estimated world shortage...
Brown makes guest appearance on American Idol [Guardian - UK] — (English)
Dr Awa Marie Coll-Seck, executive director of the Roll Back Malaria Partnership, said: "The president of the United States, along with Britain's prime minister, has shown remarkable leadership in the arena of malaria control. "We call on the rest of the global community, especially G8 member countries meeting this July in Hokkaido, Japan, to join the battle against malaria and commit the resources needed to tackle malaria once and for all." ...
20 millions de moustiquaires à l'Afrique [Le Figaro - France] — (Français)
Le Royaume-Uni va faire parvenir 20 millions de moustiquaires en Afrique pour éradiquer le paludisme, a indiqué le Premier ministre britannique Gordon Brown dans le tabloïde The Sun, invitant les hommes d'affaires et dirigeants du monde entier à en offrir 100 millions...
ExxonMobil Donates $10 Million to Anti-Malaria Efforts Through “Idol Gives Back” Episode of American Idol [Business Wire (press release) - San Francisco,CA,USA] — (English)
Exxon Mobil Corporation announced today a donation of $10 million to anti-malaria efforts through the “Idol Gives Back” episode of the FOX-TV show American Idol, which airs tonight...
Anti-Malaria pledges come fast on “Idol” fundraiser [Reuters Blogs - UK] — (English)
He hardly fits the bill as an American Idol, but British Prime Minister Gordon Brown won fans for an extraordinary pledge to buy 20 million anti-malarial nets for use in Africa and other parts of the developing world...
Brown in £100m war on malaria [The Sun - London,UK] — (English)
GORDON Brown wowed America last night by vowing to spend £100million helping eradicate malaria...
Anti – Malaria campaign starts in Eastern Uganda [ReliefWeb (press release) - Geneva,Switzerland] — (English)
A local Non Governmental Organization, Pilgrim has started a campaign to wipe out malaria in the Eastern Uganda...
The Human Side of Global Warming [Center For American Progress - Washington,DC,USA] — (English)
Currently, malaria, diarrhea, malnutrition, and floods related to climate change cause about 150,000 worldwide deaths annually, according to the World Health Organization. The range of malaria-carrying mosquitoes is spreading, too, to cooler places that have never before seen the disease, such as South Korea and the highlands of Papua New Guinea...
A Randomized Placebo-Controlled Trial of Intermittent Preventive Treatment in Pregnant Women in the Context of Insecticide Treated Nets Delivered through the Antenatal Clinic [PLOS One] — (English)
Two-dose SP was associated with a reduction in some indicators, but these were not translated to significant improvement in other maternal or birth outcomes. The use of ITNs during pregnancy may reduce the need to administer IPTp. ITNs should be part of the ANC package in sub-Saharan Africa...
Safety and Immunogenicity of a Malaria Vaccine, Plasmodium falciparum AMA-1/MSP-1 Chimeric Protein Formulated in Montanide ISA 720 in Healthy Adults [PLOS Clinical Trials] — (English)
This study is the first clinical trial for this candidate and builds on previous investigations supporting PfCP-2.9/ISA720 as a promising blood-stage malaria vaccine. Results demonstrate safety, tolerability (particularly at the lower doses tested) and immunogenicity of the formulation. Further clinical development is ongoing to explore optimizing the dose and schedule of the formulation to decrease reactogenicity without compromising immunogenicity...
Uganda begins use of DDT [Africa Science News Service - Nairobi,Kenya] — (English)
Uganda is to launch an indoor spraying of DDT programme next Friday in her war against malaria...
Souvenirs de malaria [Sud Ouest - France] — (Fran&cceil;ais)
La lutte contre les moustiques commença à La Rochelle en 1968. Quarante après, le combat continue. Une exposition en rappelle l'enjeu...
Le "charity business", version française [Le Monde - France] — (Fran&cceil;ais)
Le programme (RED) lancé en 2006 par Bono, le chanteur de U2, et l'humanitaire Bobby Shriver fonctionne en partenariat avec des entreprises (Apple, Microsoft, Dell, Gap, Emporio Armani, American Express, Converse, Motorola et Hallmark) qui déclinent certains de leurs produits (tee-shirts, ordinateurs, téléphones...) en couleur rouge ("red"). "Les marques reversent 40 % du bénéfice brut réalisé sur ces objets au Fonds mondial de lutte contre le sida, la tuberculose et le paludisme. Mais le consommateur les paie au même prix : son achat constitue un acte citoyen, et non un geste de charité", insiste Bobby Shriver...
Les populations du tiers monde sont les plus exposées aux conséquences prévues du réchauffement climatique [Newspress.fr - France] — (Français)
Selon les scientifiques, les données montrant que la terre se réchauffe sont "incontestables".La constatation de l'augmentation de la température moyenne de l'air et des eaux à l'échelle mondiale, de la fonte des glaces et de l'augmentation du niveau des mers et des océans nous aide à comprendre les problèmes à venir et à nous y préparer...
Malaria control, now a challenge [Newindpress - Chennai,Tamil Nadu,India] — (English)
Orissa Government on Tuesday claimed to have recorded a drop in malaria mortality...
8.04.2008
Malaria cases in Ireland rise by more than 100% in 12 months [Medicine Week - Ireland ] — (English)
The number of malaria cases in Ireland has doubled in a single year and more than a quarter of those infected by the disease are children, the Health Protection Surveillance Centre has revealed...
'Malaria Awareness Day' April 25 [Daily Democrat - Woodland,CA,USA] — (English)
To increase public awareness about malaria, plans are under way for the second annual Malaria Awareness Day on UC Davis campus...
Zuckerforscher auf dem Weg zum Impfstoff gegen Malaria [biotechnologie.de - Germany ] — (Deutsch)
Schon seit Jahren versucht der deutsche Glykobiologe Peter Seeberger einen Impfstoff gegen den Malariaerreger Plasmodium falciparum zu entwickeln, dem jedes Jahr vor allem Millionen von Kindern zum Opfer fallen. Nun ist der Professor an der Eidgenössischen Technischen Hochschule (ETH) in Zürich wieder ein gutes Stück vorangekommen. Er hat einen neuen Test entwickelt, mit dem sich zeigen lässt, ob eine Person gegen toxische Zuckermoleküle (GPI) des Malariaerregers Antikörper gebildet hat oder nicht...
Imported malaria in a cosmopolitan European city: a mirror image of the world epidemiological situation [Malaria Journal 2008, 7:56 (8 April 2008)] — (English)
Interesting paper about the imported malaria in Spain and its evolution...
Kenya needs 113 million dollars to combat malaria: government [AFP] — (English)
The Kenyan government needs seven billion shillings (113 million dollars, 72 million euro) to combat malaria in the country, the health ministry announced Monday...
Malaria outbreak in Bobirwa [Republic of Botswana - Gaberones,Botswana] — (English)
Six people have died of malaria in the Bobirwa area, while 201 others were treated for the disease, a public health specialist has said...
Nigeria: Malaria And Millennium Goals 4 - 5 [This Day (Lagos) via allAfrica.com] — (English)
As the world prepares for the World Malaria Day 2008, it is important that we take another look at our preparation towards this infection which is reputed to be one of the greatest killers of people, particularly pregnant women and children in sub-Saharan African...
Malaria found in PNG highlands [Radio Australia - Melbourne,Victoria,Australia] — (English)
The World Health Organisation says malaria is now appearing in the Papua New Guinea highlands and other areas once considered too cold for the mosquitoes that spread the disease to survive...
Angola: Moxico - Government Efforts in Fighting Malaria Highlighted [Angola Press Agency (Luanda) via allAfrica.com] — (English)
Angola's Health deputy minister, José Van-Dunem, said over the weekend that the government has been inserting many efforts in combat against malaria in the country...
http://www.angonoticias.com/full_headlines.php?id=19070 [Ango Notocias] — (Portuguesa)
Angop Cento e 50 milhões de dólares são empregues, durante cinco anos, no combate à malária em Angola, revelou ontem, em Luanda, o coordenador nacional adjunto do programa de luta contra a doença ...
Madagascar: Le palu menace les Hauts-plateaux [L'Express de Madagascar ] — (Français)
La recrudescence du paludisme, sous toutes ses formes, est à craindre sur les Hauts-plateaux, où l'endémie a été quelque peu vaincue ces dix dernières années. D'après le Dr Nivo Andriamampianina, chef du service de la communication et média au ministère de la Santé, du planning familial et de la protection sociale, il existe des régions où le taux du paludisme reste faible. C'est le cas des hautes terres...
Cameroun: Centre - Recrudescence du paludisme à Ngomedzap [Cameroon Tribune (Yaoundé)] — (English)
Dans le tableau épidémiologique de Ngomedzap, le paludisme tient le haut du pavé...
Poison pills [The Guardian - UK] — (English)
A 2004 study found that more than half of the antimalarials being sold in Southeast Asia contained incorrect levels of the active ingredient, and as much as 85% of the malaria drugs in Nigeria are thought to be ineffective. Substandard therapy has caused the disease to become more quickly resistant to a succession of drugs, which has contributed to a doubling of malaria deaths worldwide over the last 20 years, to more than 1.5 million people per year...
Articles requiring subscription
A history of malaria Nature Medicine 14, 363 (2008) Apr;14(4):363] — (English)
Book Review: In October 2007, Bill and Melinda Gates announced the commitment of their foundation to the eradication of malaria. Their call to action has been endorsed by the World Health Organization (WHO) and the RollBack Malaria Partnership. This is, therefore, an opportune time to be reminded of the history of malaria control and the first attempts at its eradication half a century ago. Randall M. Packard does this in his new book...
Synthetic GPI array to study antitoxic malaria response [Nature Chemical Biology 4, 238 - 240 (2008) ] — (English)
Parasite glycosylphosphatidylinositol (GPI) is an important toxin in malaria disease, and people living in malaria-endemic regions often produce high levels of anti-GPI antibodies. The natural anti-GPI antibody response needs to be understood to aid the design of an efficient carbohydrate-based antitoxin vaccine. We present a versatile approach based on a synthetic GPI glycan array to correlate anti-GPI antibody levels and protection from severe malaria...
Donors agree financial arrangement to stimulate vaccine development [BMJ 2008;336:797 (12 April), doi:10.1136/bmj.39545.371956.DB ] — (English)
An innovative financial mechanism designed to boost the development and distribution of vaccines in the developing world is set to launch next year, after publication of an expert report this month on how it will work...
Quantification of the antimalarial piperaquine in plasma [Transactions of the Royal Society of Tropical Medicine and Hygiene, Volume 102, Issue 5, May 2008, Pages 409-411] — (English)
Malaria is one of the most common parasitic diseases in the world, with up to three million deaths a year. Piperaquine is an antimalarial drug that was extensively used in China during the 1980s and has recently received renewed interest as a partner drug in artemisinin-based combination therapy. Despite extensive use, the first bioanalytical method was published in 2003. In total there are eight previously published methods for quantification of piperaquine in different biological matrices using HPLC with UV or tandem mass spectrometric detection. Five of these allow for quantification of piperaquine in plasma and are discussed in this paper...
Travel-Related Infections [Emergency Medicine Clinics of North America, Volume 26, Issue 2, May 2008, Pages 499-516] — (English)
Infections in travelers returning from international destinations are a common problem for emergency physicians. A careful travel history can help to distinguish the traveler's risk of having contracted an exotic infection, including malaria, dengue fever, and typhoid fever. The most common travel-related infection is traveler's diarrhea. A discussion of typical and rare conditions is provided, grouped by the three most common chief complaints of fever, diarrhea, and rash...
Characterisation of DDT, pyrethroid and carbamate resistance in Anopheles funestus from Obuasi, Ghana [Transactions of the Royal Society of Tropical Medicine and Hygiene, In Press, Corrected Proof, Available online 10 April 2008] — (English)
Indoor-resting anopheline mosquitoes were collected from Obuasi, Ghana, and were identified morphologically and by PCR as Anopheles funestus Giles. Wild-caught females were induced to lay eggs. Samples of F1 progeny from each family were divided into cohorts and were either exposed to DDT and permethrin or were stored for biochemical analysis. Bioassay data by family show evidence of DDT and pyrethroid resistance in the parent A. funestus population. The sodium channel gene of DDT survivors and DDT-susceptible individuals was PCR amplified and sequenced to determine whether any kdr-type mutations were present. Molecular analysis of the IIS5–IIS6 segment of the sodium channel gene gave no indication of any kdr-type mutations associated with resistance phenotypes. Biochemical analysis suggests that DDT and pyrethroid resistance may be metabolically mediated, although there were no clear correlations between enzyme levels/activities and insecticide resistance across families. Furthermore, an altered acetylcholinesterase conferring carbamate resistance was evident. These results can be used to plan an effective malaria control strategy in the Obuasi region...
Anaemia and malaria in Yanomami communities with differing access to healthcare [Transactions of the Royal Society of Tropical Medicine and Hygiene, Volume 102, Issue 5, May 2008, Pages 409-411] — (English)
Inequitable access to healthcare has a profound impact on the health of marginalised groups that typically suffer an excess burden of infectious disease morbidity and mortality. The Yanomami are traditionally semi-nomadic people living in widely dispersed communities in Amazonian Venezuela and Brazil. Only communities living in the vicinity of a health post have relatively constant access to healthcare...
HLA-B27 and Ankylosing Spondylitis geographic distribution as the result of a genetic selection induced by malaria endemic? A review supporting the hypothesis [Autoimmunity Reviews, In Press, Uncorrected Proof, Available online 9 April 2008] — (English)
The geographic distribution of HLA-B27 shows a latitude-related gradient inverse to that of malaria endemic. An apparent exception occurs in New Guinea, a region where malaria is present, but where HLA-B27 frequency shows, however, an orographic gradient antithetic to that of malaria incidence. We therefore suggest that Plasmodium falciparum may have exerted a negative selection on this gene. This might be due to a higher susceptibility to severe forms of malaria, associated with HLA-B27 or other close gene(s). In addition, we suggest here that the same selective pressure that has contributed to reduce the HLA-B27 frequency in some regions, has favoured the fixing of newly generated B27 subtypes included in more advantageous HLA haplotypes. In some cases, as for B*2709 in Sardinia and B*2706 in Southeast Asia, these haplotypes may harbour factors that protect from Ankylosing Spondylitis, an autoimmune disease strongly associated with HLA-B27, thus offering a novel, powerful tool to dissect disease pathogenesis, and to identify additional genetic factors of susceptibility...
New insight into the role of dendritic cells in malaria immune pathogenesis [Trends in Parasitology, In Press, Corrected Proof, Available online 9 April 2008] — (English)
The mechanism by which the host develops protective immunity to malaria remains poorly understood. Dendritic cells (DCs) are central to the initiation and regulation of the adaptive immune response. Modulation of DC function might enable Plasmodium to evade the immune system. Millington et al. propose one mechanism by which malaria inhibits DC–T-cell interactions without interfering directly with T-cell receptor engagement. The consequence is a decrease in the co-stimulation required to develop an effective immune response...
Plasmodium vivax in India [Trends in Parasitology, In Press, Corrected Proof, Available online 9 April 2008] — (English)
Four Plasmodium species cause malaria in humans: Plasmodium vivax is the most widespread and results in pronounced morbidity. India (population >1 billion) is a major contributor to the burden of vivax malaria. With a resurgence in interest concerning the neglected burden of vivax malaria and the completion of the P. vivax genome, it is timely to review what is known concerning P. vivax in India. The P. vivax population is highly diverse in terms of relapse patterns, drug response and clinical profiles, and highly genetically variable according to studies of antigen genes, isoenzyme markers and microsatellites. The unique epidemiology of malaria in India, where P. vivax predominates over Plasmodium falciparum, renders this location ideal for studying the dynamics of co-infection...
Parental guidance? Trans-generational influences on offspring life history in mosquitoes [Trends in Parasitology, In Press, Corrected Proof, Available online 9 April 2008] — (English)
Parental effects are important factors that might influence evolutionary and ecological aspects of parasite vectors and the parasites they transmit. A recent study demonstrated the importance of parental rearing conditions on the malaria vector Anopheles stephensi. When parents are reared in a food-limited environment their offspring have increased bloodmeal sizes and larger clutches. The study highlights that ecological studies are vital for understanding vectors of disease and ultimately for developing effective control strategies...
Morbidité et mortalité des jumeaux au CHU de Brazzaville [Journal de Pédiatrie et de Puériculture, Volume 21, Issue 2, April 2008, Pages 93-97] — (Français)
La pathologie du jumeau hospitalisé à Brazzaville est largement dominée par la gastroentérite aiguë. Le petit poids de naissance, la malnutrition et l’allaitement artificiel en sont les facteurs favorisants. La quasi-constance de l’anémie hypochrome microcytaire en constitue une autre particularité. Le meilleur suivi des grossesses gémellaires devrait considérablement contribuer à diminuer cette morbidité...
Preparing children for international travel [Travel Medicine and Infectious Disease, In Press, Corrected Proof, Available online 7 April 2008] — (English)
Travel with children may be either one of the most aggravating and trying or one of the most joyful and wondrous experiences of parenthood. What would have been a frustrating and potentially difficult journey may be transformed into a lifetime of fond memories with careful planning and realistic expectations. Although travel with children has existed since time immemorial, the field of pediatric travel medicine has only recently begun to emerge and will undergo many future changes as professional experience increases and research is conducted. This article will review current guidelines for travel medicine practitioners serving children and their families. These guidelines are based on available pediatric travel-related research, appropriately extrapolated adult and pediatric research, currently accepted practice standards, and expert opinion and experiences...
The use of artemether-lumefantrine by febrile children following national implementation of a revised drug policy in Kenya [Tropical Medicine & International Health, Volume 13, Issue 4, Page 487-494, Apr 2008] — (English)
Although Kenya was less than a year into the new policy implementation and AL is restricted to the public formal sector, access to antimalarial drugs among children within 48 h and to the first-line therapy has improved. But it remains well below national and international targets. The continued use of amodiaquine and artemisinin monotherapies constrains effective implementation of artemisinin-based combination therapy policy in Kenya...
Male Fertility of Malaria Parasites Is Determined by GCS1, a Plant-Type Reproduction Factor [Curr Biol. 2008 Apr 8] — (English)
Malaria, which is caused by Plasmodium parasites, is transmitted by anopheline mosquitoes. When gametocytes, the precursor cells of Plasmodium gametes, are transferred to a mosquito, they fertilize and proliferate, which render the mosquito infectious to the next vertebrate host. Although the fertilization of malaria parasites has been considered as a rational target for transmission-blocking vaccines, the underlying mechanism is poorly understood. Here, we show that the rodent malaria parasite gene Plasmodium berghei GENERATIVE CELL SPECIFIC 1 (PbGCS1) plays a central role in its gametic interaction. PbGCS1 knockout parasites show male sterility, resulting in unsuccessful fertilization. Because such a male-specific function of GCS1 has been observed in angiosperms and, this indicates, for the first time, that parasite sexual reproduction is controlled by a machinery common to flowering plants. Our present findings provide a new viewpoint for understanding the parasitic fertilization system and important clues for novel strategies to attack life-threatening parasites...
A stable isotope dual-labelling approach to detect multiple insemination in un-irradiated and irradiated Anopheles arabiensis mosquitoes [Parasit Vectors. 2008 Apr 10;1(1):9] — (English)
The implications of these findings for the Sterile Insect Technique are discussed, and further experiments recommended. The dual-labelling system used to determine paternity gave good results for 13C, however, for 15N it is recommended to increase the amount of label in future studies...
High mobility group protein HMGB2 is a critical regulator of plasmodium oocyst development [J. Biol. Chem, 10.1074/jbc.M801637200] — (English)
The sexual cycle of Plasmodium is required for transmission of malaria from mosquitoes to mammals, but how parasites induce the expression of genes required for the sexual stages is not known. We disrupted the Plasmodium yoelii gene encoding high mobility group nuclear factor hmgb2, which encodes a DNA binding protein potentially implicated in transcriptional regulation of malaria gene expression. We investigated its function in vivo in the vertebrate and invertebrate hosts. pyhmgb2 parasites develop into gametocytes but have drastic impairment of oocyst formation. A global transcriptome analysis of the pyhmgb2 parasites identified approximately 30 genes whose expression is downregulated in the pyhmgb2 parasites. These genes are conserved in all malaria species and more than 90% of these genes show a peak of mRNA expression at the gametocyte stage. Surprisingly, the transcripts coding for the P. berghei orthologues of those genes are stored and translated in the ookinete stage. Therefore sexual stage protein expression appears to be both transcriptionally and translationally regulated with Plasmodium HMGB2 acting as an important regulator of malaria sexual stage gene expression...
Rosetting is associated with increased Plasmodium falciparum in vivo multiplication rate in the Saimiri sciureus monkey [Microbes Infect. 2007 Dec 28] — (English)
Severe Plasmodium falciparum malaria in African children is associated with high peripheral parasite densities and high rate of rosette-forming parasites. To explore the relationship between rosette formation and parasite density in vivo, we compared the multiplication rate of a rosette-forming variant (varO) of the Palo Alto line with a sibling non-rosetting variant (varR) in splenectomized Saimiri monkeys. The multiplication rate of varO parasites was 1.5-fold higher than that of the varR variant. This indicates that rosetting is indeed associated with high parasite multiplication efficiency in vivo and, as such, may contribute to the high parasite densities observed in severe malaria...
Mast cell-mediated immune responses through IgE antibody and Toll-like receptor 4 by malarial peroxiredoxin [Eur J Immunol. 2008 Apr 9] — (English)
In this study, 2-Cys Plasmodium berghei ANKA (PbA) peroxiredoxin (Prx) was identified as an antigenic protein recognized by an anti-PbA IgE antibody using two-dimensional polyacrylamide gel electrophoresis and proteomic analysis. Innate immune responses to PbAPrx were examined using cells from mice deficient in Toll-like receptors (TLR) or related molecules, and it was demonstrated that responses were severely impaired in TLR4-/-, MyD88-/- and MD-2-/- mice, but not in Toll/IL-1 receptor domain-containing adaptor inducing IFN- (TRIF)-/-, TLR2-/- or radioprotective 105 (RP105)-/- mice. An association between PbAPrx and TLR4 was observed following immunoprecipitation and immunoblotting, suggesting that PbAPrx was associated with TLR4/MD-2. Interactions between Prx and TLR4/MD-2 were also examined by flow cytometry using TLR4/MD-2- or TLR2-expressing cells. NFB/GFP activity was observed in TLR4/MD-2- but not in TLR2-expressing cells following stimulation with Prx. However, this effect was not observed after treatment with proteinase K, suggesting that PbAPrx is a protein ligand for TLR4 and that the PbAPrx activity observed in this study is not due to contamination with LPS. These findings indicate that malarial Prx induces IgE-mediated protection through FcRI on mast cells and innate immunity through TLR4 with MyD88 and MD-2, suggesting a novel function for malarial Prx in innate and acquired immune responses in malaria...
Ubiquitin-Like Modifiers and Their Deconjugating Enzymes in Medically Important Parasitic Protozoa [Eukaryotic Cell, November 2007, p. 1943-1952, Vol. 6, No. 11] — (English)
Protein modification by ubiquitin and ubiquitin-like proteins is one of the most complex and intensely studied mechanisms of posttranslational protein regulation in eukaryotes. Conjugation of the 76-amino-acid protein ubiquitin is first and foremost a signal for targeting proteins to the proteasome for degradation, but evidence that ubiquitin also plays diverse roles in the regulation of numerous biological pathways is building. In addition, there are many structurally related ubiquitin-like modifiers (Ubls) that utilize mechanistic pathways similar to those utilized by ubiquitin for conjugation to protein substrates and deconjugation. Despite similarities in structure between ubiquitin and other Ubls, modification by Ubls regulates such diverse cellular processes as transcriptional regulation, cell cycle control, and autophagy (see Kerscher et al. [22] for a review of Ubls and known functions). Ubiquitin has been identified in the majority of parasitic protozoa, but most Ubls in these organisms have not been characterized. Even less attention has been paid to the enzymes that regulate protein modification by ubiquitin or Ubls...
Malaria after living donor liver transplantation: report of two cases [Hepatobiliary Pancreat Dis Int. 2008 Apr;7(2):210-3] — (English)
Both patients who had undergone living donor liver transplantation showed elevated levels of liver enzymes and fever during the postoperative course. Investigations (including liver biopsy in one patient) were initially inconclusive in determining the cause of liver dysfunction. The diagnosis of malaria was established in both cases by peripheral blood smear. Liver function transiently worsened with antimalarial treatment but subsequently became normal...
Plasmodium chabaudi: Efficacy of artemisinin+curcumin combination treatment on a clone selected for artemisinin resistance in mice [ Exp Parasitol. 2008 Mar 7] — (English)
Recent studies have proposed curcumin as a potential partner for artemisinin in artemisinin combination therapies to treat malaria infections. The efficacy of curcumin alone and in combination with artemisinin was evaluated on a clone of Plasmodium chabaudi selected for artemisinin resistance in vivo. The addition of piperine as an enhancer of curcumin activity was also tested...
Chloroquine mediates specific proteome oxidative damage across the erythrocytic cycle of resistant Plasmodium falciparum [Free Radic Biol Med. 2008 Mar 20] — (English)
Resistance of Plasmodium falciparum to chloroquine hinders malaria control in endemic areas. Current hypotheses on the action mechanism of chloroquine evoke its ultimate interference with the parasite's oxidative defence systems. Through carbonyl derivatization by 2,4-dinitrophenylhydrazine and proteomics, we compared oxidatively modified proteins across the parasite's intraerythrocytic stages in untreated and transiently IC50 chloroquine-treated cultures of the chloroquine-resistant P. falciparum strain Dd2. Functional plasmodial protein groups found to be most oxidatively damaged were among those central to the parasite's physiological processes, including protein folding, protein fate, energy metabolism, signal transduction, and pathogenesis. While an almost constant number of oxidized proteins was detected across the P. falciparum life cycle, chloroquine treatment led to increases in both the extent of protein oxidation and the number of proteins oxidized as the intraerythrocytic cycle progressed to mature stages. Our data provide new insights into early molecular effects produced by chloroquine in the parasite, as well as into the normal protein-oxidation modifications along the parasite cycle. Oxidized proteins involved in the particular parasite drug-response suggest that chloroquine causes specific oxidative stress, sharing common features with eukaryotic cells. Targeting these processes might provide ways of combating chloroquine-resistance and developing new antimalarial drugs...
Mannose-binding lectin variant associated with severe malaria in young African children [Microbes Infect. 2007 Dec 28] — (English)
Mannose-binding lectin (MBL) is a serum protein which initiates innate immune responses to microbial pathogens by binding to non-self surface oligosaccharides. MBL deficiency is the most common congenital immunodeficiency of human and has been shown to predispose to infections, particularly in children and immune compromised. In a matched case-control study among 870 Ghanaian children, we examined the influence of six polymorphisms of the MBL2 gene on Plasmodium falciparum infection and severe malaria. A missense mutation resulting in low MBL activity (MBL2*C) was found in 35% of healthy controls, but in 42% of asymptomatically infected children (P = 0.01), and in 46% of patients with severe malaria (P = 0.007). Heterozygosity for MBL2*C was associated with increased odds of infection (odds ratio (OR), 1.6; 95% confidence interval (CI), 1.1–2.1), severe malaria (OR, 1.7; 95% CI, 1.2–2.4), and of severe anemia in particular (OR, 2.3; 95% CI, 1.4–3.8). The population attributable fraction of severe malaria cases attributable to MBL2*C heterozygosity was 17%. Our results suggest that the MBL pathway of the complement system is a critical determinant of both, susceptibility to P. falciparum infection and manifestation of severe malaria, particularly in young children in whom specific immune responses are weak or absent...
Counter-regulatory anti-parasite cytokine responses during concurrent Plasmodium yoelii and intestinal helminth infections in mice [Exp Parasitol. 2008 Mar 7] — (English)
Malaria and helminth infections are two of the most prevalent parasitic diseases globally. While concomitant infection is common, mechanisms contributing to altered disease outcomes during co-infection remain poorly defined. We have previously reported exacerbation of normally non-lethal Plasmodium yoelii malaria in BALB/c mice chronically infected with the intestinal trematode Echinostoma caproni. The goal of the present studies was to determine the effect of helminth infection on IFN-γ and other key cytokines during malaria co-infection in the P. yoelii–E. caproni and P. yoelii–Heligmosomoides polygyrus model systems. Polyclonally stimulated spleen cells from both E. caproni- and H. polygyrus-infected mice produced significantly lower amounts of IFN-γ during P. yoelii co-infection than malaria-only infected mice. Furthermore, the magnitude of IFN-γ suppression was correlated with the relative amounts of IL-4 induced by these helminths (E. caproni = low; H. polygyrus = high), but not IL-10. Concurrent malaria infection also suppressed helminth-associated IL-4 responses, indicating that immunologic counter-regulation occurs during co-infection with malaria and intestinal helminths...
Frequent recombination events generate diversity within the multi-copy variant antigen gene families of Plasmodium falciparum [Int J Parasitol. 2008 Feb 29] — (English)
The human malaria parasite Plasmodium falciparum utilises a mechanism of antigenic variation to avoid the antibody response of its human host and thereby generates a long-term, persistent infection. This process predominantly results from systematic changes in expression of the primary erythrocyte surface antigen, a parasite-produced protein called PfEMP1 that is encoded by a repertoire of over 60 var genes in the P. falciparum genome. var genes exhibit extensive sequence diversity, both within a single parasite’s genome as well as between different parasite isolates, and thus provide a large repertoire of antigenic determinants to be alternately displayed over the course of an infection. Whilst significant work has recently been published documenting the extreme level of diversity displayed by var genes found in natural parasite populations, little work has been done regarding the mechanisms that lead to sequence diversification and heterogeneity within var genes. In the course of producing transgenic lines from the original NF54 parasite isolate, we cloned and characterised a parasite line, termed E5, which is closely related to but distinct from 3D7, the parasite used for the P. falciparum genome nucleotide sequencing project. Analysis of the E5 var gene repertoire, as well as that of the surrounding rif and stevor multi-copy gene families, identified examples of frequent recombination events within these gene families, including an example of a duplicative transposition which indicates that recombination events play a significant role in the generation of diversity within the antigen encoding genes of P. falciparum...
Investigations of the effects of the antimalarial drug dihydroartemisinin (DHA) using the Frog Embryo Teratogenesis Assay-Xenopus (FETAX) [Reprod Toxicol. 2008 Feb 29] — (English)
Artemisinin derivatives are effective and safe drugs for treating malaria, but they are not recommended during the first trimester of pregnancy because of resorptions and abnormalities observed in animal reproduction studies. Previous studies in rats showed that artemisinin embryotoxicity derives from the depletion of primitive red blood cells (RBCs) over a narrow critical time window (gestation Days 9–14). In order to further investigate the susceptibility of primitive RBCs to artemisinins and to establish whether this susceptibility is species-specific or inherent to the compound, we studied dihydroartemisinin (DHA), both a drug in its own right and the main metabolite of current artemisinin derivatives in use, in the Frog Embryo Teratogenesis Assay-Xenopus (FETAX). This model readily allows investigation and monitoring of primitive and definitive RBCs. Effects on frog larvae exposed to DHA for 48 h during early embryonic development, starting from 24 h post fertilization, were similar to those on rat embryos in terms of reduction in the number of primitive RBCs (clonally produced within the ventral blood island). In contrast, RBCs of older larvae (stage 47, produced at the definitive sites of hematopoiesis) were affected minimally and subsequently recovered. Compared to rat embryos, the frog larvae had no areas of necrosis but they shared similar heart defects. The mitochondrion appeared to be the main subcellular target, similar to observations in Plasmodium. These results implicate artemisinin-induced embryotoxicity through perturbation of metabolically active RBCs; whereas this mode of action does not appear to be species-specific, the stages of susceptibility varied between different species. The window of susceptibility and duration of exposure must be considered to evaluate the clinical relevance of these findings...
Insecticide treated mosquito nets for malaria control in India-experience from a tribal area on operational feasibility and uptake [Mem Inst Oswaldo Cruz. 2008 Mar 27] — (English)
The study assessed the operational feasibility and acceptability of insecticide-treated mosquito nets (ITNs) in one Primary Health Centre (PHC) in a falciparum malaria endemic district in the state of Orissa, India, where 74% of the people are tribes and DDT indoor residual spraying had been withdrawn and ITNs introduced by the National Vector Borne Disease Control Programme...
A magneto-optic route towards the in-vivo diagnosis of malaria: preliminary results and pre-clinical trial data [Biophys J. 2008 Apr 4] — (English)
We report the development of a new magneto-optic technology for the rapid quantitative diagnosis of malaria that may also be realisable in a non-invasive format. Haemozoin, the waste product of malarial parasitic action on haemoglobin, is produced in a form that under the action of an applied magnetic field gives rise to an induced optical dichroism characteristic of the haemozoin concentration. Here we show that precise measurement of this induced dichroism may be used to determine the level of malarial infection since this correlates, albeit in a complex manner throughout the infection cycle, with the concentration of haemozoin in the blood and tissues of infected patients. Under conservative assumptions for the production of haemozoin as a function of parasitemia, initial results indicate that the technique can match or exceed other current diagnostic techniques. The validity of the approach is confirmed by a small preliminary clinical trial on thirteen patients whilst measurements on live parasitized cells obtained from in vitro culture verify the possibility of producing in-vivo diagnostic instrumentation...
Spontaneous splenic rupture due to Plasmodium vivax in a traveler [J Travel Med. 2008 Mar-Apr;15(2):140; author reply 140-2] — (English)
We read with great interest the case report and review of the literature on spontaneous splenic rupture due to Plasmodium vivax.1 This is a relatively uncommon, yet life-threatening complication of P vivax. However, we are concerned that the authors are underestimating the true number of reported cases of splenic rupture due to malaria. The authors stated that there were 19 cases of splenic rupture due to malaria reported since 1960 in the English literature, 12 of these cases due to P vivax. We were able to locate at least nine additional cases reported in the English literature since 1960, seven due to P vivax. Review of the literature further indicates that the incidence of splenic rupture complicating P vivax malaria may actually be 1% to 2%...
Prepared in cooperation with WHO ANGOLA INFO.
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