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Chikungunya infection is a febrile illness, which currently is afflicting the Caribbean islands including the Dominican Republic. We would like to report our experience with Chikungunya-related musculoskeletal manifestations in our arthritis clinics in the Dominican Republic. A total of 514 patients presented for the first time to our arthritis clinic exhibiting musculoskeletal manifestations, 473/514 (92%) exhibiting symmetric polyarthralgias, 344/514 (67%) arthritis, and 385 (75%) skin rash. The great majority 457.46 (89%) exhibited very good clinical response to nonsteroidal anti-inflammatory drugs (NSAIDs), 370 (72%) require low-dose steroids, and only 5 patients (0.97%) required methotrexate therapy. In addition, of a total of 328 patients with rheumatoid arthritis on biological treatment, 53 exhibited Chikungunya-related musculoskeletal manifestations; 51/53 (96.2%) exhibited symmetric polyarthralgias, 25/53 (47.1%) arthritis, and 13/53 (24.5%) tendinopathy. Of most patients, 51/53 responded to NSAIDs, of which, 23 patients only responded partially, and in total 25 (47.1%) required low-dose steroids. Disease-modifying antirheumatic drug (DMARD) therapy including biologics remained unchanged in this population.

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Anti-malarial resistance in Plasmodium falciparum remains an obstacle for malaria control. Resistance-associated genes were analysed in Brazilian samples over four decades to evaluate the impact of different treatment regimens on the parasite genetic profile. Methods: Samples were collected on filter paper from patients infected in the Amazon region from 1984 to 2011.DNA was extracted with Chelex® 100 and monoinfection confirmed by PCR. SNPs in the pfcrt, pfmdr1, pfdhfr and pfdhpsgenes were assessed by PCR-RFLP. The pfmdr1 copy number was estimated using real time quantitative PCR with SYBR®Green. Parasite response was assessed ex vivo with seven concentrations of each anti-malarial. Patients were treatedaccording to Brazilian guidelines: quinine plus tetracycline or mefloquine in period 1 and ACT in period 2...

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Most medicinal plants used against malaria in endemic areas aim to treat the acute symptoms of the disease such as high temperature fevers with periodicity and chills. In some endemic areas of the Brazilian Amazon region one medicinal plant seems to be an exception: Ampelozyziphus amazonicus, locally named "Indian beer" or "Saracura-mira", used to prevent the disease when taken daily as a cold suspension of powdered dried roots. In previous work we found no activity of the plant extracts against malaria blood parasites in experimentally infected animals (mice and chickens) or in cultures of Plasmodium falciparum. However, in infections induced by sporozoites, chickens treated with plant extracts were partially protected against Plasmodium gallinaceum and showed reduced numbers of exoerythrocytic forms in the brain. We now present stronger evidence that the ethanolic extract of "Indian beer" roots hampers in vitro and in vivo development of Plasmodium berghei sporozoites, a rodent malaria parasite. Some mice treated with high doses of the plant extract did not become infected after sporozoite inoculation, whereas others had a delayed prepatent period and lower parasitemia. Our data validates the use of "Indian beer" as a remedy for malaria prophylaxis in the Amazon, where the plant exists and the disease represents an important problem which is difficult to control. Studies aiming to identify the active compounds responsible for the herein described causal prophylactic activity are needed and may lead to a new antimalarial prophylactic.

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In Colombia, Plasmodium resistance to antimalarials such as chloroquine and antifolates is a serious problem. As a result, the national Colombian health authorities are monitoring the efficacy of alternative drugs and schemes. The study of genetic polymorphisms related with drug resistance is required in the region. In vitro responses to chloroquine, quinine, mefloquine, amodiaquine, desethylamodiaquine, artesunate and dihydroartesunate were carried out by HRP ELISA. SNP analysis in Pfcrt and Pfmdr1 genes was performed by PCR-RFLP in 77 samples from the North West region of Colombia. In vitro resistance to chloroquine was high (74%), followed by mefloquine (30%) and desethylamodiaquine (30%). A positive correlation between the IC(50) of paired drugs was also detected. The allele Pfmdr1 N86 (wild) was present in 100% of the samples and 1246Y (mutant) in 92%. However, their presence did not correlate with in vitro drug resistance. Presence of the mutations K76T and N75E in Pfcrt was confirmed in all samples. Analysis of 4 codons (72, 74, 75 and 76) in pfcrt confirmed the presence of the haplotypes CMET in 91% and SMET in 9% of the samples.

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The population structure of Plasmodium falciparum has been widely studied in diverse epidemiological contexts, but emphasis has been made in regions with high and stable transmission. In order to establish the genetic structure of P. falciparum in areas of Colombia with different degree of endemicity, we studied 100 samples from malaria patients of two different municipalities. The frequency of multiclonal infection in these areas and the correlation with the endemicity were carried out by comparison of the amplified products from polymorphic segments of MSP-1, MSP-2, and GLURP genes. We found low size polymorphism of the studied genes: 1 MSP-1 allele, 3 MSP-2 alleles, and 4 GLURP alleles. We conclude that the P. falciparum population in the regions studied is genetically homogeneous.

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Foram realizadas análise microbiológica, físico-químicas e microscópicas de 15 amostras diferentes de polpa de fruta congelada de uma única marca comercial, com o objetivo de verificar a qualidade destas polpas, uma vez que, säo consumidas in natura. Os resultados obtidos indicaram que, do ponto de vista microbiológico, todas as amostras analisadas atendiam à legislaçäo em vigor. Entretanto, as análises físico-químicas mostraram que, das 13 amostras que apresentam limites estabelecidos pela legislaçäo vigente, 4 (31 por cento) se enquadravam como produto em desacordo com a mesma legislaçäo. As polpas de abacaxi e morango näo apresentam padröes legais de identidade e qualidade. As análises microscópicas mostraram que 60 por cento das amostras apresentaram fragmentos e/ou larvas de insetos e àcaros. Foram também detectados fragmentos micelianos. Os resultados indicaram que 53 por cento das amostras foram enquadradas como produtos inaceitáveis para o cusumo, quanto às características microscópicas. Portanto, existe a necessidade de estabelecer métodos que sirvam como padräo para o controle microscópico destes produtos, além da exigência de contagem de filamentos micelianos em polpas de frutas congeladas

Microbiological, physical-chemical and microscopic analyses of 15 samples of frozen fruitpulp, from a single commercial brand, were carried out to verify pulp quality, because they are consumedin natura.The results have shown that, from the microbiological point of view, all samples were in compliancewith the present legislation. However, the physical-chemical analyses showed that 4 (31%) of the sampleswere not in compliance with this legislation. The identity and quality of pineapple and strawberry pulp arenot contemplated by the legislation. The microscopic analyses showed that 60% of the samples presentedfragments and/or larvae of insects and acarids. Micelial fragments were also detected. The results indicatedthat 53% of the samples were unacceptable for consumption according to the legislation. Therefore,methods need to be established in order to serve as a model for the microscopic control of these products,in addition to the necessity of counting micelial filaments in frozen fruit pulp

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The apical membrane antigen (AMA-1) family of malaria merozoite proteins is characterised by a high degree of inter-species conservation. Evidence that the protein (PK66/AMA-1) from the simian parasite Plasmodium knowlesi was protective in rhesus monkeys suggested that the 83kDa P. falciparum equivalent (PF83/AMA-1) should be investigated for protective effects in humans. Here we briefly review pertinent comparative data, and describe the use of an eukaryotic full length recombinant PF83/AMA-1 molecule to develop a sensitive ELISA for the determination of serological responses in endemic populations. The assay has revealed surprisingly high levels of humoral response to this quantitatively minor antigen. We also show that PK66/AMA-1 inhibitory mAb's are active against merozoites subsequent to release from schizont-infected red cells, further implicating AMA-1 molecules in red cell invasion.

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Pyrimethamine resistance in cultivated laboratory isolates of Plasmodium falciparum is linked to the dihydrofolate reductase mutation Asn-108, a mutation that acts by interrupting drug binding within the active site of the enzyme. To determine the prevalence of this mutation in endemic regions harboring pyrimethamine-resistant malaria, we used a mutation-specific polymerase chain reaction assay to survey P. falciparum strains from a wide section of the Brazilian Amazon. Mutations were identified directly from blood samples without intervening steps of in vitro cultivation. Of 42 samples collected from four states in Brazil, 38 (90%) contained the Asn-108 codon AAC that confers pyrimethamine resistance, four samples contained only the wild-type Ser-108 codon AGC, and none contained the Thr-108 codon ACC found in cycloguanil-resistant pyrimethamine-sensitive strains. These findings indicate that a very high incidence of the Asn-108 DHFR mutation is responsible for pyrimethamine resistance in the Amazon, and they are consistent with recent failure rates reported for Fansidar (pyrimethamine-sulfadoxine). We suggest that limited use of proguanil be evaluated as an alternative to pyrimethamine.

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After reviewing the use of non-human primates of the Old and New Worlds for human malaria research, we concluded that another experimental animal which is easily available to use and possible to rear indoors is needed. Thus, we studied the susceptibility of the marmoset Callithrix penicillata to Plasmodium falciparum erythrocytic infections. The marmosets received various P. falciparum human isolates, directly from a patient and from continuous cultures. The Palo Alto strain, which has been adapted to the night monkey Aotus trivirgatus and further maintained in the squirrel monkey Saimiri sciureus was also used. In a total of 20 marmosets we performed 31 inoculations, with 10(5) to 10(9) parasites, intraperitoneally, intracardiacly or intravenously. Blood samples from each animal were examined daily up to day 90 post-inoculation. None of the intact marmosets developed patent infections. Four out of 19 C. penicillata, previously splenectomized, showed circulating parasites for up to five days after intravenous inoculation with the Palo Alto strain, becoming negative thereafter. Neither the addition to the simian diet of p-aminobenzoic acid, essential for the parasite metabolism, nor drug-immunosuppression, improved the marmoset susceptibility to P. falciparum.

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The expression by Plasmodium falciparum of a specific S-antigen has been examined in primary isolates in different regions of the world using a monoclonal antibody that recognizes an epitope within a known repeated amino acid sequence. The epitope was expressed by a small proportion of primary isolates in each of Brazil, Thailand and Papua New Guinea, demonstrating that this S-antigen gene is widespread. The data are consistent with the possibility that the occurrence of P. falciparum strains expressing a particular S-antigen is periodic, related to the duration of immunity against that antigen in a given human population.

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