Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0024530 (malaria)
 44,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A normal-phase high-performance liquid chromatographic method using dichloromethane-methanol-1 M perchloric acid (100:9:0.4, v/v) at a flow-rate of 0.8 ml/min on a Zorbax-Sil column with fluorescence detection has been developed for the separation of quinine and quinidine from other antimalarials. Within-day and day-to-day coefficients of variation averaged 0.74 and 7.56%, respectively. The extraction recovery of quinine for plasma, serum, red blood cells and whole blood (filter paper) was 88.13, 87.12, 78.0 and 77.5%, respectively. The method is capable of separating quinine from dihydroquinine, a compound usually found as an impurity in authentic quinine samples. The method has been used for the determination of quinine in plasma, serum, red blood cells and whole blood (filter paper) of six healthy and twenty Plasmodium falciparum malaria cases. The average quinine concentration in P. falciparum malaria cases was three to four times higher than that in healthy volunteers. Quinine was absorbed much less in red blood cells than in plasma or serum.
 ...
PMID:Determination of quinine in serum, plasma, red blood cells and whole blood in healthy and Plasmodium falciparum malaria cases by high-performance liquid chromatography. 849 90

Retarded development of exoerythrocytic stages of the rodent malaria parasite Plasmodium berghei in human hepatoma cells by extracts from Dioncophyllaceae and Ancistrocladaceae species. International Journal for Parasitology 27: 29-32. Naphthylisoquinoline alkaloid-containing extracts (10 micrograms ml-1) of species belonging to the Dioncophyllaceae and the Ancistrocladaceae, 2 small tropical plant families, display pronounced in vitro activities against exoerythrocytic stages of Plasmodium berghei (Anka), developing in human hepatoma cells (Hep G2). The highest activities were obtained with CH2Cl2 root and bark extracts, and a CH2Cl2/NH3 leaf extract from Triphyophyllum peltatum, a CH2Cl2/NH3 root extract from Ancistrocladus abbreviatus, and a CH2Cl2 leaf extract from A. tectorius. The degrees of growth inhibition ranged within 27.7-70.0%. The commercially available drug primaquine diphosphate (25 micrograms ml-1) caused a comparable effect (62.1%) in the same test system.
 ...
PMID:Retarded development of exoerythrocytic stages of the rodent malaria parasite Plasmodium berghei in human hepatoma cells by extracts from Dioncophyllaceae and Ancistrocladaceae species. 907 26

We present an evaluation of the antiplasmodial and cytotoxic effects of four plants commonly used in Guatemalan folk medicine against malaria. Methanol extracts of Simarouba glauca D. C., Sansevieria guineensis Willd, Croton guatemalensis Lotsy, and Neurolaena lobata (L.)R.Br. significantly reduced parasitemias in Plasmodium berghei-infected mice. Dichloromethane fractions were screened for their cytotoxicities on Artemia salina (brine shrimp) larvae, and 50% inhibitory concentrations were determined for Plasmodium falciparum in in vitro cultures. Both chloroquine-susceptible and -resistant strains of P. falciparum were significantly inhibited by these extracts. Of all dichloromethane extracts, only the S. glauca cortex extract was considered to be toxic to nauplii of A. salina in the brine shrimp test.
 ...
PMID:In vivo and in vitro antiplasmodial activities of some plants traditionally used in Guatemala against malaria. 921 Jun 73

Twenty extracts including ten EtOH and ten CH2Cl2 from different parts of nine African medicinal plants used in Congolese traditional medicine for the treatment of malaria, were submitted to a pharmacological test in order to evaluate their effect on P. falciparum growth in vitro. Of these plant species, 14 (70%) extracts including EtOH and CH2Cl2 from Cassia occidentalis leaves, Cryptolepis sanguinolenta root bark, Euphorbia hirta whole plant, Garcinia kola stem bark and seeds, Morinda lucida leaves and Phyllanthus niruri whole plant produced more than 60% inhibition of the parasite growth in vitro at a test concentration of 6 microg/ml. Extracts from E. hirta, C. sanguinolenta and M. morindoides showed a significant chemosuppression of parasitaemia in mice infected with P. berghei berghei at orally given doses of 100-400 mg/kg per day.
 ...
PMID:Antimalarial activity of 20 crude extracts from nine African medicinal plants used in Kinshasa, Congo. 1062 78

A simple, sensitive, selective, and reproducible reversed-phase high-performance liquid chromatographic (HPLC) method with UV detection was developed for the determination of lorazepam (LZP) in human plasma, using oxazepam (OZP) as internal standard. LZP and OZP were extracted from alkalinized (pH 9.5) spiked and clinical plasma samples using a single step liquid-liquid extraction with a mixture of n-hexane-dichloromethane (70:30%; v/v). Chromatographic separation was performed on a reversed-phase Synergi Max RP analytical column (150 mmx4.6 mm i.d.; 4 microm particle size), using an aqueous mobile phase (10 mM KH2PO4 buffer (pH 2.4)-acetonitrile; 65:35%, v/v) delivered at a flow-rate of 2.5 ml/min. Retention times for OZP and LZP were 10.2 and 11.9 min, respectively. Calibration curves were linear from 10 to 300 ng with correlation coefficients (r2) better than 0.99. The limits of detection (LOD) and quantification (LOQ) were 2.5 and 10 ng/ml, respectively, using 0.5 ml samples. The mean relative recoveries at 20 and 300 ng/ml were 84.1+/-5.5% (n=6) and 72.4+/-5.9% (n=7), respectively; for OZP at 200 ng the value was 68.2+/-6.8% (n=14). The intra-assay relative standard deviations (R.S.D.) at 20, 150 and 270 ng/ml of LZP were 7.8%, 9.8% (n=7 in all cases) and 6.6% (n=8), respectively. The inter-assay R.S.D. at the above concentrations were 15.9%, 7.7% and 8.4% (n=7 in all cases), respectively. Intra- and inter-assay accuracy data were within the acceptance interval of +/-20% of the nominal values. There was no interference from other commonly co-administered anticonvulsant, antimicrobial, antipyretic, and antimalarial drugs. The method has been successfully applied to a pharmacokinetic study of LZP in children with severe malaria and convulsions following administration of a single intravenous dose (0.1 mg/kg body weight) of LZP.
 ...
PMID:Determination of lorazepam in plasma from children by high-performance liquid chromatography with UV detection. 1611 23

During the course of screening Ethiopian medicinal plants for their antimalarial properties, it was found that the dichloromethane extract of the roots of Kniphofia foliosa Hochst. (Asphodelaceae), which have long been used in the traditional medicine of Ethiopia for the treatment of abdominal cramps and wound healing, displayed strong in vitro antiplasmodial activity against the chloroquine-sensitive 3D7 strain of Plasmodium falciparum with an ED50 value of 3.8 microg/mL and weak cytotoxic activity against KB cells with an ED50 value of 35.2 microg/mL. Five compounds were isolated from the roots and evaluated for their in vitro antimalarial activity. Among the compounds tested, 10-(chrysophanol-7'-yl)-10-(xi)-hydroxychrysopanol-9-anthrone and chryslandicin, showed a high inhibition of the growth of the malaria parasite, P. falciparum with ED50 values of 0.260 and 0.537 microg/mL, respectively, while the naphthalene derivative, 2-acetyl-1-hydroxy-8-methoxy-3-methylnaphthalene, exhibited a less significant antimalarial activity with an ED50 value of 15.4 microg/mL. To compare the effect on the parasite with toxicity to mammalian cells, the cytotoxic activities of the isolated compounds against the KB cell line were evaluated and 10-(chrysophanol-7'-yl)-10-(xi)-hydroxychrysopanol-9-anthrone and chryslandicin displayed very low toxicity with ED50 values of 104 and 90 microg/mL, respectively. This is the first report of the inhibition of the growth of P. falciparum by anthraquinone-anthrone dimers and establishes them as a new class of potential antimalarial compounds with very little host cell toxicity.
 ...
PMID:Antimalarial compounds from Kniphofia foliosa roots. 1611 82

Sixty-six extracts of 18 plants commonly used by traditional healers in Congo Brazzaville for the treatment of malaria have been investigated for in vitro antiplasmodial activity. Ethanolic and dichloromethane extracts of 7 among the 18 studied plants were moderately active (10 microg/ml<IC(50)<50 microg/ml). These extracts concerned Cassia siamea (bark), Cogniauxia podolaena (root), Landolphia lanceolata (root and leaves), Millettia versicolor (leaves), Pseudospondias microcarpa (leaves), Uapaca paludosa (leaves) and Vernonia brazzavillensis (leaves). These results support their traditional use as antimalarial plants. The bark extract of Uapaca paludosa showed a good activity (<10 microg/ml) and the extracts from Quassia africana (root and leaves) even exhibited IC(50) values less than 1 microg/ml. Except for Quassia africana, for which the three solvents (water, ethanol and dichloromethane) present an effective extraction, no aqueous extract was highly active. The cytotoxicity of aqueous, DCM and ethanol extracts of Quassia africana was tested on KB cell lines.
 ...
PMID:In vitro antiplasmodial activity of 18 plants used in Congo Brazzaville traditional medicine. 1625 60

The in vitro antiplasmodial activity of 117 aqueous, methanol and dichloromethane extracts derived from different parts of 28 indigenous wild plant species was studied. These plants are commonly used in Cambodian traditional medicine. The plant extracts were tested for in vitro activity against a chloroquine resistant Plasmodium falciparum strain (W2). Nine extracts were moderately active with IC(50) values ranging between 5 and 10 microg/ml, 17 extracts were active with IC(50) values ranging between 1 and 5 microg/ml. These 26 extracts derived from eight plants belong to six families. The most active extracts were dichloromethane and came from Stephania rotunda and Brucea javanica with IC(50) values of 1 microg/ml and a selectivity index > or = 25. It is interesting to note that some aqueous extracts were as active as dichloromethane extracts especially aqueous extracts of Stephania rotunda, Brucea javanica, Phyllanthus urinaria and Eurycoma longifolia with IC(50) values of < or = 4 microg/ml. These results are in agreement with statements of healers on traditional uses of these plants for the treatment of malaria and/or fever. In this study, we report the antiplasmodial potential activity of eight plant species from Cambodia. Among them four are tested for the first time.
 ...
PMID:Screening of selected indigenous plants of Cambodia for antiplasmodial activity. 1654 36

Artemisinin is extracted from Artemisia annua, a shrub also known as sweet wormwood that was used in traditional medicine in Asia for more than 1500 years. Recent studies in numerous malarious zones have demonstrated the effectiveness of artemisinin and have reported no evidence of the resistance now associated with almost all other antimalarials on the market. Despite its remarkable activity, artermisinin is not accessible to many patients due to high cost. This situation confronts all players in the fight against malaria with the urgent need to develop a simple process to produce massive supplies of artemisinin and its derivative at an affordable price. The purpose of the study described here was to develop a simple, cost-effective method that could be used by all professionals to extract artemisinin and transform it into artesunate or artemether. Artemisinin was extracted with dichloromethane and purified on the basis of variations in polarity and in the hydrophile/lipophile balance of solvents. Transformation into artesunate was a two-step process involving reduction to dihydroartemisinin using diisobutylaluminium hydride (DIBAL) followed by esterification using succinic anhydride. Artemether was obtained from dihydroartemisinin using boron trifluoride. Extraction using dichloromethane presents several advantages. Since dichloromethane is not explosive it can be safely transported and used for extraction on farms where Artemisia annua is grown. Evaporation and recovery of dichloromethane is relatively easy so that it can be re-used. These advantages result in a significant decrease in purchasing and shipping costs. Extraction on the farm eliminates the expense and facilities that would otherwise be required to transport and store leaves at the laboratory (250 kg of leaves yield 4 to 5 kg of raw artemisinin extract that yields approximately 1 kg of pure artemisinin). The low-cost process described here is feasible for any pharmaceutical laboratory including those in developing countries.
 ...
PMID:[Extraction of artemisinin and synthesis of its derivates artesunate and artemether]. 1728 32

Stephania rotunda (Menispermaceae) is used in traditional medicine for the treatment of fever. Four major alkaloids: dehydroroemerine, tetrahydropalmatine, xylopinine, cepharanthine as well as aqueous extract (SA), dichloromethane extracts (SD1 and SD2) from this plant were tested against Plasmodium falciparum W2 in vitro. Dehydroroemerine, cepharanthine and SD1 were the most active against W2 with IC(50) of 0.36, 0.61microM and 0.7microg/mL, respectively. Their IC(50) on human monocytic THP1 cells were 10.8, 10.3microM and >250microg/mL, respectively. Cepharanthine, SD1 and SA were selected for in vivo antimalarial test against Plasmodium berghei in mice. The results of SD1 and SA at dose of 150mg/kg showed a decrease of 89 and 74% of parasitaemia by intra-peritoneal injection and 62.5 and 46.5% of parasitaemia by oral administration, respectively. The result of cepharanthine at dose of 10mg/kg showed a decrease of 47% of parasitaemia by intra-peritoneal injection and 50% of parasitaemia by oral administration. Drug interaction of chloroquine and major alkaloids indicates that cepharanthine-chloroquine and tetrahydropalmatine-xylopinine associations are synergistic. These results are in agreement with the use of this plant in the treatment of malaria. This is the first report on in vivo antimalarial investigation for Stephania rotunda.
 ...
PMID:Antimalarial activity of alkaloids isolated from Stephania rotunda. 1738 2


1 2 3 4 Next >>