IN VITRO POTENCY AND TOXICITY OF STREPTOMYCES SP. FERMENTATION PRODUCT AS AN ANTIMALARIAL THERAPY AGAINST PLASMODIUM FALCIPARUM

Objective: This research aims to study the activity of a Streptomyces sp. fermentation product as an antimalarial modality in HepG2 cells.Methods: The effects of the product against Plasmodium falciparum 3D7 were examined using an in vitro technique parasite. The potency of theStreptomyces sp. fermentation product was examined by determining the half maximal inhibitory concentration (IC50), and the mechanism wasstudied using transmission electron microscopy (TEM). Toxicity tests were also conducted.Results: The Streptomyces sp. fermentation product had an IC50 of 0.001 μg/ml against the parasite, versus values of 0.054 and 0.022 μg/ml forquinidine and prodigiosin, respectively. TEM revealed no formation of hemozoin. The Streptomyces sp. fermentation product was non-toxic in HepG2cells based on its cytotoxicity concentration 50% of 1.380 μg/ml.Conclusion: The Streptomyces sp. fermentation product has potential as a potent and non-toxic antimalarial therapy

IN VITRO ANTIMALARIAL POTENCY OF ELEUTHERINE BULBOSA AND ITS EFFECT ON THE MORPHOLOGY OF PLASMODIUM FALCIPARUM

Objective: This study aimed to determine the potential inhibitory effects of Eleutherine bulbosa on the growth of Plasmodium falciparum and its toxiceffects on lymphocyte cells.Methods: We performed a 50% inhibition concentration (IC50) test of E. bulbosa against P. falciparum, used transmission electron microscopy (TEM)to observe Plasmodium morphology after exposure to E. bulbosa, and determined E. bulbosa’s cytotoxic concentration 50% (CC50) against lymphocytes.Results: The IC50 value of E. bulbosa was 0.62 μg/ml. We observed crystals in the mitochondria of parasites under TEM. CC50 values at 24 h and 72 hwere 851.14 μg/ml and 707.94 μg/ml, respectively.Conclusion: The main content of E. bulbosa is naphthoquinones that are suspected of having a mitochondrial target on the malaria parasite. E. bulbosais not toxic to lymphocytes; therefore, it has a potential as an antimalarial therapeutic

Detection of the Resistance of Parasite to Sulfadoxine-pyrimethamine Drugs and msp-2 Genotyping as A Baseline in Developing Malaria Vaccine with Ionizing Radiation

Polymorphism or mutation in specific genes of P. falciparum and P. vivax is involved in the resistance to sulfadoxine-pyrimethamine (SP) antimalarial drug. On the other hand msp-2 gene plays an important role in drug resistance related genotyping. This study was undertaken as a basic information in assessing the urgent of development of malaria vaccine that can be created by ionizing radiation. Deoxy ribonucleic acid (DNA) of blood from malaria infected outpatients in Dok II Hospital of Jayapura for November 2014 period was amplified using nested polymerase chain reaction (PCR) and followed by restriction fragment length polymorphism (RFLP) analysis to determine the polymorphisms of SP resistance. Among 15 samples tested for dhfr gene, 9 (60%) and 8 (53%) samples showed positive result for polymorphisms in JR78/79 and F/108DH primers, respectively. For dhps gene by using JR84/85 and L/L primers 7 samples were positive mutant. These frequencies are lower compared to results of other research. Of these 15 samples examined, 3 had 3D7 alleles and 4 had FC27 alleles of the msp2 gene. No mutated S1105 and S1240 alleles and 6 mutant VDT alleles were found in P. vivax. It can be concluded that the resistance of parasites to SP was quite high, indicating the highly urgency to develop malaria vaccine

Phycocyanin Extraction from Spirulina platensis and Its Antimalarial Activity In-Vitro

Phycocyanin is a pigment-protein complex from the light-harvesting phycobiliprotein family which isoften found in cyanobacteria. The product phycocyanin produced by phanizomenon flos-aquae and Spirulinasp. The aim of this study were to determine the best solvents purification phycocanin from Spirulina platensisin three solvents, phosphate buffer, water and aceton ammonium sulphate and to evaluate the antimalarialactivity in vitro of phycocyanin in the best solvent extraction from S. platensis. The method of this study wasusing in-vitro antimalarial method. The result showed C- phycocyanin (C-PC), yield, and protein contentsof phycocyanin were 8 mg/mL, 20.22%, 1.88% extracted and purified by phosphate buffer, 6.63 mg/mL,16.58 %, 3.51% extracted and purified by water, 2.86 mg/mL, 7.15%, 8.4% extracted and purified by acetoneammonium sulphate respectively. Phosphate buffer was the best solvent of phycocyanin extraction from S.platensis. Antimalarial activity in vitro of phycocyanin in hosphate buffer against Plasmodium falciparumstrains 3D7 with IC50 was 158,489 μg/mL. The possible mechanism might be relied on the destruction ofpolymerization of Haemozoin by binding of C-PC with ferriprotoporphyrin-IX at the water surface of theplasma membrane

A Robust Segmentation for Malaria Parasite Detection of Thick Blood Smear Microscopic Images

Parasite Detection on thick blood smears is a critical step in Malaria diagnosis. Most of the thick blood smear microscopic images have the following characteristics: high noise, a similar intensity between background and foreground, and the presence of artifacts. This situation makes the detection process becomes complicated. In this paper, we proposed a robust segmentation technique for malaria parasite detection of microscopic images obtained from various endemic places in Indonesia. The proposed method includes pre-processing, blood component segmentation using intensity slicing and morphological operation, blood component classification utilising rule based on properties of parasite candidates, and parasite candidate formation. The performance was evaluated on 30 thick blood smear microscopic images. The experimental results showed that the proposed segmentation method was robust to the different condition of image and histogram. It reduced the misclassification error and relative foreground error by 2.6% and 45.5%, respectively. Properties addition to blood component classification increased the system precision. Average of precision, recall, and F-measure of the proposed method were all 86%. It is proven that the proposed method is appropriate to be used for malaria parasites detection

Incorporating Index of Fuzziness and Adaptive Thresholding for Image Segmentation

Binary Segmentation of an image played an important role in many image processing application. An image that was having no bimodal (or nearly) histogram accompanied by low-contrast was still a challenging segmentation problem to address. In this paper, we proposed a new segmentation strategy to images with very irregular histogram and had not significant contrast using index of fuzziness and adaptive thresholding. Index of fuzziness was used to determine the initial threshold, while adaptive thresholding was used to refine the coarse segmentation results. The used data were grayscale images from related papers previously. Moreover, the proposed method would be tested on the grayscale images of malaria parasite candidates from thickblood smear that had the same problem with this research. The experimental results showed that the proposed method achieved higher segmentation accuracy and lower estimation error than other methods. The method also effective proven to segment malaria parasite candidates from thickblood smears image

Segmentation of Malaria Parasite Candidate from Thickblood Smear Microscopic Images using Watershed and Adaptive Thresholding

Segmentation of malaria parasite on thick blood smear is a critical intermediate step in automation process of malaria detection. Most of the thick blood smear have low quality that characterized by high noise, the low-intensity difference between background and foreground, and the presence of artifacts. This situation makes the segmentation process becomes difficult. In this paper we proposed a new segmentation strategy for microscopic images of malaria parasite obtained from thick blood smear using watershed and adaptive thresholding. The proposed method consists of two main stages: image enhancement and segmentation. Enhancement process used Low-pass filtering and contrast stretching. Meanwhile, the segmentation used combination watershed segmentation and adaptive thresholding. The performance was evaluated on 253 parasite candidates, cropped from 22 thick blood smear microphotographs. The experimental results showed that the average segmentation accuracy of the proposed algorithm was 95.2%. Further analysis showed that the nucleus and cytoplasm of the malaria parasite were successfully extracted, thus the method is suitable for being used on detection of malaria parasites

The plasma membrane calcium ATPase 4 does not influence parasite levels but partially promotes experimental cerebral malaria during murine blood stage malaria

From Springer Nature via Jisc Publications RouterHistory: received 2021-03-03, accepted 2021-06-24, registration 2021-06-24, pub-electronic 2021-07-02, online 2021-07-02, collection 2021-12Publication status: PublishedFunder: Medical Research Council; doi: http://dx.doi.org/10.13039/501100000265; Grant(s): MR/P015816/1Abstract: Background: Recent genome wide analysis studies have identified a strong association between single nucleotide variations within the human ATP2B4 gene and susceptibility to severe malaria. The ATP2B4 gene encodes the plasma membrane calcium ATPase 4 (PMCA4), which is responsible for controlling the physiological level of intracellular calcium in many cell types, including red blood cells (RBCs). It is, therefore, postulated that genetic differences in the activity or expression level of PMCA4 alters intracellular Ca2+ levels and affects RBC hydration, modulating the invasion and growth of the Plasmodium parasite within its target host cell. Methods: In this study the course of three different Plasmodium spp. infections were examined in mice with systemic knockout of Pmca4 expression. Results: Ablation of PMCA4 reduced the size of RBCs and their haemoglobin content but did not affect RBC maturation and reticulocyte count. Surprisingly, knockout of PMCA4 did not significantly alter peripheral parasite burdens or the dynamics of blood stage Plasmodium chabaudi infection or reticulocyte-restricted Plasmodium yoelii infection. Interestingly, although ablation of PMCA4 did not affect peripheral parasite levels during Plasmodium berghei infection, it did promote slight protection against experimental cerebral malaria, associated with a minor reduction in antigen-experienced T cell accumulation in the brain. Conclusions: The finding suggests that PMCA4 may play a minor role in the development of severe malarial complications, but that this appears independent of direct effects on parasite invasion, growth or survival within RBCs