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Fenugreek in Management of Immunological, Infectious, and Malignant Disorders
Published in Dilip Ghosh, Prasad Thakurdesai, Fenugreek, 2022
Rohini Pujari, Prasad Thakurdesai
Culex quinquefasciatus, commonly known as the southern house mosquito, is a medium-sized mosquito found in tropical and subtropical regions. The 3rd–4th instar larvae of Cx. quinquefasciatus laboratory colony was reported with high susceptibility during in vitro assay with 100% and 98% mortality (to the water and ethanol extract of fenugreek at 30% and 20% concentration respectively) (Fallatah 2010). In this study, fenugreek extracts cellular vacuolization and disintegration and rupture of the epithelial layer of muscles, nerve ganglia, midgut, hindgut of larvae with significant protein loss to suggest high larvicidal properties against mosquitos (Fallatah 2010). In another study, ethanolic extracts of fenugreek leaves and two fractions (ethanol and butanol) demonstrated potent in vitro anti-plasmodial assay against laboratory-adapted chloroquine-sensitive and -resistant P. falciparum isolates during Schizont maturation inhibition assay (Palaniswamy et al. 2010).
Candida and parasitic infection: Helminths, trichomoniasis, lice, scabies, and malaria
Published in Hung N. Winn, Frank A. Chervenak, Roberto Romero, Clinical Maternal-Fetal Medicine Online, 2021
Malaria is typically caused by infection with one of four protozoa, Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale, or Plasmodium malariae. Humans are infected with malaria when bitten by an Anopheles mosquito carrying the organism. Plasmodium sporozoites are transferred from the mosquito to the human bloodstream, where they travel to the liver and infect liver cells. Inside the liver cells, the sporozoite matures to a schizont, which then ruptures releasing merozoites that invade erythrocytes and either multiple asexually to develop a ring stage schizont (which will again rupture releasing merozoites) or develop into a gametocyte. The gametocytes can then be taken up by the Anopheles mosquito to begin the mosquito portion of their life cycle, which includes fertilization of the female gametocyte in the mosquito stomach, maturation in the mosquito midgut wall, and migration of the mature sporozoites to the mosquito salivary gland for injection during the next mosquito blood meal to begin the human portion of the life cycle.
Malaria Vaccines: Prospects and Problems
Published in Max J. Miller, E. J. Love, Parasitic Diseases: Treatment and Control, 2020
There does not seem to be a single immunodominant protective molecule, and it is possible that more than one of the candidate antigens will be needed to produce an effective blood-stage vaccine. Colombian workers have also shown that specific proteins from late schizont and merozoite stages of P. falciparum can be used to vaccinate monkeys against malaria. Recently, they reported that a combination of three partially effective peptides, which they have synthesized corresponding to the protein fragments, have excellent protection.12 Patarroyo et al. have now described two polymeric synthetic hybrid proteins based on the above peptides that delayed or suppressed the development of parasitemia in immunized human volunteers.12a
Recent advances in quantitative structure–activity relationship models of antimalarial drugs
Published in Expert Opinion on Drug Discovery, 2021
Probir Kumar Ojha, Vinay Kumar, Joyita Roy, Kunal Roy
The life cycle of the parasites [3] completes in two stages such as asexual stage (liver and erythrocyte stages in human host) and sexual stage (inside the mosquito) [3]. The host infection starts with the bite of female Anopheles mosquito (taking the blood meal from infected human) and sporozoites injected into the human skin capillaries. This sporozoites make their way to the cells of the liver within 30 min of injecting and starts replicating asexually [3]. The schizonts rupture to give haploids form (merozoites) within 6 to 15 days in the blood stream [3]. The invasion of the merozoites gives rise to the erythrocytic stage [3,4]. In this stage, they multiply further mitotically and pass through ring forms then the feeding stage, i.e., trophozoites, then to the reproductive stage (schizonts) over the next 48 hours which gives birth of 16 new daughter merozoites for each schizont [3,4]. After maturation, the schizonts burst giving new merozoites to the blood stream [3]. The released merozoites further inject new erythrocytes to start new fever cycle that causes the clinical symptom of malaria [3]. After few cycles, the merozoites tend to develop male and female gametocytes, i.e., sexual forms (diploid zygotes) instead of new merozoites circulating into the blood stream [3,4]. They form oocyst and travel to the midgut wall of the mosquito and within 8 to 15 days sporozoites develop and migrate to the salivary glands of the mosquitoes [3]. The host infection begins when the mosquito takes blood meal and further injects sporozoites into the human blood stream [3].
The early preclinical and clinical development of ganaplacide (KAF156), a novel antimalarial compound
Published in Expert Opinion on Investigational Drugs, 2018
Robin Koller, Ghyslain Mombo-Ngoma, Martin P. Grobusch
Kuhen et al. published the preclinical antimalarial profile of ganaplacide as it emerged from in vitro and in vivo mouse model studies [11]. Plasmodium vivax and P. falciparum parasites were collected from malaria patients at two sites from where multidrug resistance has been reported in both P. falciparum and P. vivax; namely Papua Indonesia and the Thai-Myanmar border region [11]. Firstly, an ex vivo schizont maturation assay was performed to measure the inhibitory activity of ganaplacide on the development of asexual parasites. Median IC50 values were 12.6 nM (3.5–27.1 nM) for P. falciparum and 5.5 nM (1.4–65.8 nM) for P. vivax, respectively. Also, P. vivax and P. falciparum parasites from both sites were found to be significantly more sensitive to ganaplacide than to chloroquine; however, drug-susceptibility to artesunate was greater [11].
Humanized mouse models infected with human Plasmodium species for antimalarial drug discovery
Published in Expert Opinion on Drug Discovery, 2018
Alicia Moreno-Sabater, Jean Louis Pérignon, Dominique Mazier, Catherine Lavazec, Valerie Soulard
An added value of the HmHPf-ES is that it can also give precious information about compound activity against resistant strains. Thus, new compounds such as PA1103/SAR116242, and SC81458 and SC83288 have shown an excellent activity in mice infected with the P. falciparum 3D7 strain as well as against the chloroquine-resistant P. falciparum W2 strain [47,65]. Other authors have taken advantage of the characteristic of this model – in which the different stages of the parasite are free in the circulation – to determine against which stage was acting the compound DDD107498, i.e. at the early ring stage or at the later mature schizont stage [59].