Effect of Ramadan fasting on salivary IgA, serum IgA, IL-17, and IL-22 levels.

Background: nutritional factors might affect the number and function of immune cells for instance the production of cytokines and immunoglobulins. Ramadan fasting is intermittent abstinence from eating and drinking for almost four weeks. Aim: The present study aimed to investigate the influence of intermittent fasting on serum IgA, salivary IgA (sIgA), interleukin (IL)-17, and IL-22 levels. Methods: 40 healthy men aged 19-29 years were evaluated before and during the fourth week of Ramadan fasting for IgA levels by the nephelometric method as well as salivary IgA (sIgA), IL-17, and IL-22 amounts using enzyme-linked immunosorbent assay (ELISA). Results: serum IgA levels reduced significantly at the end of Ramadan fasting (225.8 ± 87 vs. 196 ± 70 mg/dl) (p-value<0.001); however, sIgA amounts did not differ between before and the last week of Ramadan. Serum IL-17 reduced significantly (2.93 ± 1.51 vs. 2.17 ± 1.33 pg/ml) (p-value = 0.006) whereas IL-22 levels remained approximately unchanged. Summary: four weeks of intermittent fasting during Ramadan reduced the serum levels of IgA and IL-17 but did not affect the production of sIgA and IL-22. These findings indicate a limited impact of intermittent fasting on mucosal immunity.

Induction of Artesunate Resistance in Plasmodium falciparum 3D7 Strain Using Intermittent Exposure Method and Comparing P.fk13 Sequence between Susceptible and Resistant Strains.

Background: Resistance to artemisinin has threatened major achievements in malaria control, more investigations is needed about resistant strains and related genes. We aimed to induce resistance to artesunate in the Plasmodium falciparum 3D7 strain using intermittent exposure method and comparing P.fk13 gene sequence between susceptible and resistance strains. Methods: P. falciparum 3D7 strain was cultured according to Trager & Jensen method with some modifications. Serial concentrations between 10-2 mol/l, to 10-7mol/l were prepared, then P. falciparum 3D7 was exposed to each of the dilution to determine IC50 and lethal dose. Sensitivity reduction process was started from the concentration of 10-7mol/l and ended at 10-2mol/l. Exposed parasites were collected after at least 27 days after cultivation in each drug concentration. DNA extraction, PCR and sequencing process were performed to investigate any possible mutations in the P.fk13 gene sequence. Results: Effectiveness of 10-2mol/l concentration of artemisinin was found as a lethal dose. IC50 value was equal to 5×10-4 mol/l. The resistant strain was provided in the lab, sequenced and registered in the gene bank as P.f Art -2, (accession number MH796123. 1). Alignment of this registered sample showed no mutation in P.f kelch13 gene in comparison with standard strain submitted in the GenBank. Conclusion: Resistance to artesunate in malaria parasite may occur but with no mutation in the P.f kelch13 gene. Therefore, whole genome sequencing should be applied to determine mutations in resistant strains.

Cytotoxicity and Anti-Plasmodium berghei Activity of Emodin Loaded Nanoemulsion.

Background: Malaria parasites cause a tremendous burden of disease in both the tropics and subtropics areas. Growing of drugs resistance in parasites is one of the most threats to malaria control. The aim of study was to investigate the anti-malarial activity of nano-emodin isolated from Rhamnus cathartica on Plasmodium berghei in mice to evaluate parasites inhibition rate using in-vivo test. Methods: The study was conducted in the School of Public Health, Tehran University of Medical Sciences, during 2020. Nano-emodin particles were prepared from Rhamnus cathartica, and confirmed by Zeta Potential Analyzer, DLS and electron microscopy techniques. Mice were infected with P. berghei and treated by emodin nano-particles. Parasitemia was evaluated in each group in comparison with control group. Toxicity test was done using twice the highest concentration of emodin extract on a separate group of mice and ED50 was calculated. Results: Emodin extract was significantly effective in all concentrations on D4 (P<0.05). The most effective on parasitemia was observed in 400 mg/kg of Liquid Nano-emodin and solid (non-Nano) emodin. ED50 for emodin extract was determined 220 mg/kg. Toxicity test showed no toxic effect on the subjects. Conclusion: The emodin extract is safe, lack of side effects. So, it can be used for more and longer period of time and in higher doses. Emodin extract, either in form of liquid and nanoparticle or in a solid form, has the same therapeutic effect on P. berghei in infected Balb/c mice.

Development and optimizing a simple and cost-effective medium for in vitro culture of Plasmodium berghei-ANKA strain with conserving its infectivity in BALB/c mice.

OBJECTIVES: The current culture system for P. berghei still requires modifications in consistency and long-term maintenance of parasites considering their pathogenicity in culture media. Therefore, this study designed to further improvement of culture conditions and designing a cost-effective culture medium with minimum changes in pathogenicity for in vitro culture of P. berghei. RESULTS: Results indicated that the rate of parasitaemia in our modified method remained statistically stable between days one to seven (P = 0.07). The current modified cultivation method was more efficient in maintaining of parasites for further days. Furthermore, in current method the stability of parasitaemia rate during day1 to day7 was in better rate compared to that in Ronan Jambou et al. and the differences between two methods were statistically significant (P = 0.001). The virulence of cultivated parasites in our modified method remained similar to frozen stock parasites as positive control group. No significant differences were seen in survival time between two groups of mice those were infected with either cultivated parasites or stock freeze parasites (P = 0.39) with the mean survival time of 20.83 ± 3.84 and 19.66 ± 1.21 days, respectively. Herein, we achieved a simple, cost-effective and applicable technique for culture of P. berghei.

Phytochemical Composition and Bioassay on Iranian Teucrium Polium Extracts against Anopheles Stephensi (Diptera: Culicidae).

Background: Anopheles stephensi is an important malaria vector mosquito in Iran and other western Asian countries. In many human communities, plant products have been used traditionally instead of synthetic pesticides for mosquito control due to their minimal hazardous effects. Teucrium polium, known popularly as felty germander, has been introduced in Persian Medicine (PM) as an insect repellent from a long time ago. Methods: The present study was undertaken to evaluate repellent and larvicidal activity of dichloromethane (DCMETP) and ethanolic extracts (EE-TP) of T. polium against An. stephensi under laboratory conditions. The possible chemical components of the extracts were also investigated through gas chromatography/mass spectrometry (GC-MS) technique. Results: Based on the results, DCME-TP showed better repellent activity than EE-TP with 56.67 and 28.33 % protection, respectively. Larvicidal activity of DCME-TP with 49.41% mortality was also higher than EE-TP (20.24%). The main identified constituents of DCME-TP were long chain alkanes, phenol, aromatic ester, oxaspiro and triterpenoid. While phenolic and aliphatic acid were only the identified components in EE-TP. It is notable that lupeol was detected in DCME of T. polium for the first time. Conclusion: DCME-TP can be considered as a new herbal candidate to control An. stephensi mosquitoes. Further studies are required on this extract for the fractionation and identification of the active compounds, and the evaluation of their bioactivity in the laboratory and field.

Potential of RH5 Antisense on Plasmodium falciparum Proliferation Abatement.

Background: Infections by Plasmodium falciparum, are becoming increasingly difficult to treat. Therefore, there is an urgent need for novel antimalarial agents' discovery against infection. In present study, we described a 2'-O-Methyl gapmer phosphorothioate oligonucleotide antisense targeting translation initiation region of 3D7 strain RH5 gene. Methods: The study was conducted in Pasteur Institute of Iran in 2020. ODNs effects were measured by microscopic examination and real time RT-PCR. For microscopy, microplates were charged with 2'-OMe ODNs at different dilutions. Unsynchronized parasites were added to a total of 0.4 ml (0.4% parasitemia, 5% red blood cells), and slides were prepared. Proportion of infected cells was measured by counting at least 500 red blood cells. Results: RH5 genes start codon regions selected as conserved region besed on alignment results. Gap-RH5-As which was complementary to sequence surrounding AUG RH5 start codon significantly reduced parasite growth (>90% at 50 nM) compared to sense sequence control (Gap-RH5-Se) (17%), (P<0.001). RH5 transcripts were dramatically reduced after exposed to ODNs at a concentration of 5-500 nM for 48 h. Conclusion: Gemnosis delivery of a chimeric gapmer PS-ODN with 2'-OMe modifications at both sides had high antisense activity at low concentrations (10-100 nM) and shown a good efficiency to reach to target mRNA in human RBCs. Anti-parasite effect was correlated to reduction of target gene mRNA level. In addition, 2'-OMe ODNs free delivery is an effective way and does not need any carrier molecules or particles.

Detection of Malaria Parasites and Other Haemosporidia in Migratory and Native Birds in Mazandaran and Golestan Provinces, Iran.

Background: A variety of haemoprotozoa including Plasmodium, Haemoproteus and Leucocytozoon cause infections in birds and are transmitted by some known vectors. These parasites cause anemia, low appetite, weakness and ultimately death in birds. The present study was aimed to determine these parasites, in birds of Mazandaran and Golestan provinces in Iran. Methods: The project was performed on 340 live birds in 2016. The samples were collected from February to September 2016, from each bird, two thin and thick blood smears were prepared and the remaining blood about 1ml was kept in EDTA-containing tubes for molecular studies. The slides were stained with 10% Giemsa, then examined microscopically. About ten percent of the negative samples were considered for Polymerase Chain Reaction (PCR) technique, using specific primers to diagnose Plasmodium and Haemoproteus spp. Electrophoresis was done for PCR products and relevant bands to the parasites were identified based on the size. The considered birds belonged to ducks, chickens, roosters, and pigeons. Results: From 340 microscopically examined blood samples 32 (9.5%) samples were positive. Twenty-five (7.35%) of them were infected with the genus Haemoproteus. Seven samples (14%) out of 50 microscopically negative samples were found as Haemoproteus or Plasmodium spp when PCR technique was employed. Conclusion: This study revealed the existence of malaria parasites and other haemosporidia in birds in Iran. Employing molecular methods (PCR examination) could detect more infections.

Serological responses to a soluble recombinant circumsporozoite protein-VK210 of Plasmodium vivax (rPvCSP-VK210) among Iranian malaria patients.

BACKGROUND: Circumsporozoite protein (CSP) has a central immune domain that includes short regions of repeating amino acid sequences. This immunodynamic region is an epitope of B cells that can elicit an immune response in human and laboratory animals. The aim of the present study was to express the recombinant PvCSP-VK210 antigen and evaluate it for assaying antibodies obtained during human P. vivax infection by Western blotting and indirect ELISA (enzyme-linked immunosorbent assay). METHOD: Genomic DNA of P. vivax was isolated from a blood sample of an Iranian person with vivax malaria, and by PCR, the fragment of the PvCSP-VK210 gene was amplified. The gene fragment was cut after gel purification by BamHI and HindIII enzymes and then cloned into pET28a expression vector. Finally, the recombinant pET28a was transformed into the E. coli BL21 (DE3) as the expression host. In order to produce His-tagged protein, the expression host was cultured in LB medium. The protein was purified by Ni-NTA columns and immobilized metal affinity chromatography, and after confirmation by Western blotting technique, was used as the antigen in the indirect ELISA test. RESULTS: The recombinant protein was expressed and purified as a 32-kDa protein. The sensitivity and specificity of the indirect ELISA test with the recombinant PvCSP-VK210 antigen were 61.42% and 97.14%, respectively, based on OD = 0.313. Between the results of the microscopic test and the indirect ELISA test with the recombinant PvCSP-VK210 antigen there was a Kappa coefficient of 0.586. The positive and negative predictive value and validity of the ELISA test with the recombinant PvCSP-VK210 antigen were 95.55%, 71.57%, 79.28%, respectively. CONCLUSION: The sensitivity of the indirect ELISA method with the recombinant PvCSP-VK210 antigen was 61.42%, which is the first report from Iran.

Interaction between Chitosan and Chloroquine against Plasmodium berghei and P. falciparum Using In-Vivo and In-Vitro Tests.

BACKGROUND: The use of antimalarial drugs with number of compounds in combination form may potentiate each other's activity. METHODS: This study was conducted in the School of Public Health, Tehran University of Medical Sciences, Tehran, Iran in 2018. It was based on two methods including in vivo and in vitro tests with aim of considering interaction between chitosan and chloroquine against Plasmodium berghei and P. falciparum parasites using different ratios of the agents with ED50s and IC50s baselines. RESULTS: Administrating 10 and 20 mg/kg (mouse body weight) of chitosan alone to the P. berghei -infected mice up to 4 successive days resulted in 37% and 45% inhibition of P. berghei respectively, while employing the compound with chloroquine in combination form with ratios of 90/10 and 70/30 (chloroquine/chitosan) had a considerable potentiation including 71.58% and 83.85% inhibition effectiveness against P. berghei. Moreover, 20 mg/L (CCM) concentration of chitosan alone could eliminate 69.55% of P. falciparum in culture medium while in combination with chloroquine in ratios of 90/10 (chloroquine/chitosan) had considerable potentiation including 79.14% inhibition effectiveness. Mean survival time of those mice received combination therapy in ratios of 90/10 and 70/30 (chloroquine/chitosan) was longer than those took up mono therapy of either chloroquine or chitosan based on their ED50s doses. CONCLUSION: Interaction between chloroquine and chitosan showed considerable potentiation in combination form against either P. berghei or P. falciparum using in vivo and in vitro tests respectively. Meanwhile, interaction between the above mentioned agents resulted in a notable survival time for those P. berghei-infected mice treated with the combination.

A systematic review and meta-analysis of asymptomatic malaria infection in pregnant women in Sub-Saharan Africa: A challenge for malaria elimination efforts.

BACKGROUND: In Sub-Saharan Africa (SSA), where malaria transmission is stable, malaria infection in pregnancy adversely affects pregnant women, fetuses, and newborns and is often asymptomatic. So far, a plethora of primary studies have been carried out on asymptomatic malaria infection in pregnant women in SSA. Nevertheless, no meta-analysis estimated the burden of asymptomatic malaria infection in pregnant women in SSA, so this meta-analysis was carried out to bridge this gap. METHODS: PubMed, Web of Science, Scopus, Embase, and ProQuest were systematically searched for relevant studies published until 4 August 2020, and also the expansion of the search was performed by October 24, 2020. We assessed heterogeneity among included studies using I-squared statistics (I2). Publication bias was assessed by visual inspection of the funnel plot and further quantitatively validated by Egger's and Begg's tests. The pooled prevalence and pooled odds ratio (OR) and their corresponding 95% Confidence Interval (CI) were estimated using the random-effects model in Stata 15 software. RESULTS: For this meta-analysis, we included 35 eligible studies. The overall prevalence estimate of asymptomatic Plasmodium infection prevalence was 26.1%% (95%CI: 21-31.2%, I2 = 99.0%). According to species-specific pooled prevalence estimate, Plasmodium falciparum was dominant species (22.1%, 95%CI: 17.1-27.2%, I2 = 98.6%), followed by Plasmodium vivax, Plasmodium malariae and Plasmodium ovale, respectively, found to be 3% (95%CI: 0-5%, I2 = 88.3%), 0.8% (95%CI: 0.3-0.13%, I2 = 60.5%), and 0.2% (95%CI: -0.01-0.5%, I2 = 31.5%). Asymptomatic malaria-infected pregnant women were 2.28 times more likely anemic (OR = 2.28, 95%CI: 1.66-3.13, I2 = 56.3%) than in non-infected pregnant women. Asymptomatic malaria infection was 1.54 times higher (OR = 1.54, 95%CI: 1.28-1.85, I2 = 11.5%) in primigravida women compared to multigravida women. CONCLUSION: In SSA, asymptomatic malaria infection in pregnant women is prevalent, and it is associated with an increased likelihood of anemia compared to non-infected pregnant women. Thus, screening of asymptomatic pregnant women for malaria and anemia should be included as part of antenatal care.

High-Resolution Melting Analysis in Comparison with Microscopic Method: An Experimental Study to Diagnosis of Plasmodium Species Infections in Human.

BACKGROUND: Among the human parasitic diseases, malaria is the main cause of morbidity and mortality. To prevent the high mortality and tracking malaria elimination efforts, a prompt and sensitive diagnosis is essential. This study aimed to compare High-Resolution Melting (HRM) and microscopic methods to diagnose Plasmodium falciparum and P. vivax. METHODS: Eighty-one blood samples were collected from patients with clinical symptoms who were suspect to malaria in Chabahar district, southeastern Iran and also, from those who were referred to Malaria National Laboratory in the Tehran University of Medical Sciences, Tehran, Iran. Microscopic examination and HRM method were used to the diagnosis of Plasmodium parasites simultaneously. RESULTS: Microscopic results revealed 45 positive cases (12 P. falciparum and 33 P. vivax) out of 81 collected samples while according to HRM analysis results 11 and 33 samples were identified as P. falciparum and P. vivax, respectively. HRM analysis also revealed 1 mixed infection of P. falciparum and P. malariae. CONCLUSION: HRM analysis provides a promising mean for simultaneous detection and discrimination of the Plasmodium spp. especially in mixed infection cases.

Genotyping and Phylogenetic Analysis of Plasmodium vivax Circumsporozoite Protein (PvCSP) Gene of Clinical Isolates in South-Eastern Iran.

BACKGROUND: Circumsporozoite protein (CSP) is one of the most important surface sporozoite antigens in malaria, recently considered as a candidate for vaccination. Considering the importance of CSP, this study was conducted to investigate the polymorphism and genetic diversity of Plasmodium vivax Circumsporozoite Protein (Pvcsp) in the southeastern region of Iran during 2015-2016. METHODS: To investigate polymorphism and genetic diversity, 20 blood samples were collected from patients with P. vivax, then DNA was extracted and amplified using partial sequence of CSP gene. Polymerase chain reaction (PCR) products were sequenced and compared to sequences from genomic databases using BLAST. Genetic evaluation and phylogenic analysis were performed using MEGA7 and DnaSP5 software's on 38 sequences include 20 sequences of our study and 18 sequences of Gene Bank. RESULTS: Eleven isolates were VK210 genotype and 9 isolates contained VK247. The result of variable segregation nucleotide site indicated that the differentiation of sequences in CSP were 25.67% in our 20 samples which are less than the 38 samples with a value of 26.67%. Comparing the ratio of dN/dS regions in the CSP gene indicates that the CSP varies more synonymously and amino acid has lower variation. Out of 38 samples, 35 unique haplotypes were identified based on 1042 nucleotide sequences in CSP, showing a variation percentage of 99.4%. CONCLUSION: The Tajima D analyses showed that CSP gene in P. vivax had a positive number in the total analyzed sequences, which means that the P. vivax mutations are in order to select positive evolution.

Application of High-Resolution Melting (HRM) Technique towards the Detection of Asymptomatic Malaria in a Malaria Endemic Area of Southeastern Iran under Elimination Program.

BACKGROUND: Asymptomatic malaria, which usually exists in low parasitemia, acts as the Plasmodium species reservoirs contributing towards malaria transmission. This situation hinders malaria elimination programs in endemic areas, thus necessitating an active case detection with a high sensitive method and treatment of cases. This is why we used a High Resolution Melting (HRM) assay to monitor the trend of asymptomatic malaria in a malaria endemic area of Iran which is under elimination program. METHODS: The peripheral blood was sampled from 271 clinically approved non-febrile individuals from a malaria endemic zone of southeastern Iran for asymptomatic malaria prevalence detection by microscopy, Rapid Diagnostic Tests (RDTs) and HRM methods. The HRM assay was done based on the amplification of 18S SSU rRNA gene. RESULTS: The HRM assay revealed infections from three individuals out of 271 (1.1% asymptomatic malaria prevalence) from the participants, two Iranian natives with Plasmodium vivax infection and one Pakistani immigrant with P. falciparum infection. Neither microscopy nor RDTs detected Plasmodium spp infections from the 271 non-febrile individuals. The nucleotide sequencing analysis of the positive controls used in this study showed a close homology with the reference gene bank sequences of P. falciparum 3D7 (CPO16995.1) and P. vivax Sal-1(UO3079.1). CONCLUSION: This study revealed a low frequency of asymptomatic malaria trend within malaria endemic areas of southeastern Iran which are under intense elimination program and also the ability of HRM assay in detecting low Plasmodium spp parasitemia beyond the limits of microscopy and RDTs.

Situation of Asymptomatic Malaria among Iranian Native and Afghan and Pakistani Immigrants in a Malarious Area under the National Malaria Elimination Program of Iran.

BACKGROUND: This study was designed to detect, if there are asymptomatic malaria infections amongst native and immigrant population from Afghanistan and Pakistan countries in Sistan & Baluchistan Province of Iran, where is under the national malaria elimination program. METHODS: This cross-sectional study was performed among native individuals and resident immigrants in the southeastern province of Sistan & Baluchistan from May 2016 to Jul 2017. A total of 271 individuals were considered in this cross-sectional study based on microscopical method, Rapid Diagnostic Tests (RDTs) and PCR techniques. Out of 271 native and immigrant participants 140 (52%) and 131 (48%) were male and female, respectively. RESULTS: None of the prepared samples was diagnosed as malaria positive case when was considered via above mentioned three techniques. CONCLUSION: Neither native nor immigrant individuals had asymptomatic malaria, hinting that national malaria elimination program is performed according to planned schedule in the studied areas.

Identification of Alleles in the MSP1 Gene Related to Complicated Malaria in Patients Infected with Plasmodium falciparum in Southeast of Iran.

BACKGROUND: To overcome human malaria problem several solutions have been employed including extensive studies in the field of Plasmodia relevant antigens. The aim of this study was to determine allelic variation in the MSP1 gene of Plasmodium falciparum among some falciparum malaria-infected patients in Southeastern Iran. METHODS: Twenty P. falciparum positive cases were enrolled from Sistan and Baluchistan Province, southeastern Iran in 2013-15. From each case, 1.5ml of peripheral blood was collected into EDTA contained tubes. Thick and thin blood smears were stained with standard Giemsa stain and were checked with conventional microscopical method. DNA was extracted from blood samples and amplification of block 2 MSP1 was performed using specific primers. Gel electrophoresis was done and results showed some amplification fragments corresponding to block 2 regions of Pf MSP1 gene. Finally, four samples from different allelic types were sent for sequencing process. RESULTS: Fragments were different in size, so classified into six allelic types as kinds of 1-6 based on happening frequencies. Digestion of PCR products revealed two sub allelic types (A and B) within allelic types 2 and 3, but not in allelic types 1, 4, 5 and 6. Twenty percent of samples were sent for sequencing. Sequence alignment showed 78.95% to 91.83% identity between samples. CONCLUSION: Identity between samples and phylogenetic tree revealed that there is an extensive diversity range among isolates. Fifty percent of the isolates were under the risk of complicated malaria. Two of these patients (10%) needed special care and recovery was obtained after getting hospital services.

Allelic Variations of Plasmodium vivax Apical Membrane Antigen-1 (Pv AMA-1) in Malarious Areas of Southeastern Iran Using PCR-RFLP Technique.

BACKGROUND: Although Plasmodium vivax is usually known as benign malaria, some variations of the parasite can result in acute and sever infection. In this study we tried to determine some genetic variations in PvAMA-1 antigen among the samples were collected form southeastern Iran. METHODS: About two ml blood samples were collected into EDTA pre-dosed tubes from 30 P. vivax-infected patients individually between 2011 and 2013. A Giemsa stained thick and thin blood film was prepared from each of the patients. A PCR-RFLP technique was employed using EcoR-1, Pvu-II and Hind3 restriction enzymes to determine the allelic variations of the antigen. RESULTS: A 1300bp gene corresponding to PvAMA-1 was selected for the amplification process. Among the total cases identified in this study 90% showed similar bounds when exposed to the restriction enzymes. Nine isolates (accession numbers: KF435081-KF435083 and JF682785-JF682790) were identified and registered in Gene bank. Identity among isolates was more than 96% in nucleotide level. Dendrogram clarified a close relationship among the clusters in spite of geographical distribution of the parasite. CONCLUSION: This study increased our data about prevalence and variation of PvAMA-1 alleles amongst P. vivax isolates in southeastern parts of Iran where besides native population bears considerable Afghan and Pakistani immigrants.

In Vivo Anti-Malarial Activity of Heracleum persicum Fruit Extract, in Combination with Chloroquine against Chloroquine-Sensitive Strain of Plasmodium berghei.

BACKGROUND: We evaluated the anti-malarial activity of Heracleum persicum individually and in combination with chloroquine. METHODS: This study was conducted at the School of Public Health, Tehran University of Medical Sciences, Tehran, Iran in 2015-2016. The Peter's method was used for determining fifty percent effective dose (ED50) of the H. persicum extract and chloroquine individually against chloroquine sensitive P. berghei in small white mice. Six experimental groups for H. persicum and 6 groups for chloroquine and two control group (positive and negative) were considered for determination of ED50. Interaction between H. persicum and chloroquine also was evaluated based on fixed ratios method. Ratios of 0/100, 20/80, 40/60, 60/40, 80/20, 100/0 of ED50 of chloroquine and H. persicum respectively were tested against the parasite. Then inhibitory effects of two drugs were calculated and plotted in the relevant graphs. RESULTS: Overall, 1500 mg/kg, and 1000 mg/kg concentrations of H. persicum against P. berghei resulted in ED50 and ED74 respectively. ED50 of chloroquine against the parasite was obtained as 1.4 mg/kg of mouse body weight. Moreover, combination of H. persicum and chloroquine showed a weak potentiation in ratios of 40/60 (chloroquine +H. persicum) with 64% inhibition, but not in other ratios. CONCLUSION: Although H. persicum individually showed a reasonable antimalarial efficacy against chloroquine sensitive P. berghei, in combination with chloroquine it showed additive or antagonism result except in ratios of 40%CQ+60%HP.

Monitoring the Response of Plasmodium vivax to Chloroquine and Uncomplicated P. falciparum to Artesunate-fansidar Antimalarials in Southeastern Iran.

BACKGROUND: For many years, malaria was a major life-threatening parasitic infection in Iran. Although malaria elimination program is implementing in the country, still some cases annually are reported from malaria-endemic areas. METHODS: This study was conducted in five malaria endemic districts of Sistan and Baluchistan Province, southeastern Iran, neighboring Afghanistan and Pakistan countries. Overall, 170 and 38 vivax malaria and falciparum malaria infected patients were enrolled in the study from 2013-2014. All the cases were selected according to criteria of the WHO guideline for in vivo drug sensitivity tests in malaria parasites. Evaluation of drug sensitivity test was conducted with some modifications. RESULTS: The patients with vivax malaria responded to the regimen of chloroquine in 37.4(±15.9), 40(±13.8) and 42(±17.7) h for Pakistani, Iranian and Afghani nationalities respectively based on MPCT evaluation. The results showed a considerable difference between them and Iranian subjects. MPCT for the patients with falciparum malaria was calculated as 28(±18.05), 26(±12.03) and 36(±16.9) h for Iranian, Pakistani and Afghani nationalities respectively. There was a marginally significant difference between Afghani and other nationalities and between males and females. CONCLUSION: Treatment of all the patients resulted in ACPR and MPCT of P. vivax showed that the parasite became more sensitive to chloroquine than previous years in studied areas.