Evaluation of haematological changes in Plasmodium-berghei-infected mice administered with aqueous extract of Phyllantus amarus.

This study was designed to evaluate the changes in some hematological parameters of P-berghei-infected mice treated with aqueous extract of Phyllantus amarus, a plant that is used traditionally to treat malaria patients in some Nigerian communities. The aqueous extract of the leaves at 200, 400 and 600 mg kg(-1) body weight/day dose levels were used to treat the test groups immediately after infection for the suppressive test and 72 hours post infection for the curative test while a standard antimalarial drug, Artesunate, at a dose of 50 mg kg(-1) body weight was administered on the positive control group. The negative control group was left untreated. The level of parasitemia, variation in weight, Percentage Packed Cell Volume (% PCV), erythrocytes (RBC) and leukocytes (WBC) counts in the different groups were monitored throughout the period of study. The crude extract was screened for its phytochemical composition. The crude extract at 200, 400 and 600 mg kg(-1) body weight/day suppressed parasitemia by 54.67, 61.25 and 61.24% after treating for four days in the suppressive test as against 72.32% for the standard drug while the level of parasitemia was reduced by 64.35, 66.71 and 67.13%, respectively after treating for five days in the curative test as against 71.87% for the standard drug. The variations in the values of Percentage Packed Cell Volume (% PCV), weight, leukocyte and erythrocyte counts for treated groups before and after treatment was not significant (p < 0.05). Alkaloids, flavonoids, tannins, glycosides, saponin, carbohydrate and phenols were found to be present in the crude extract. The findings of this study show that the use of Phyllantus amarus as antimalaria regimen by local medical practitioners does not adversely affect the weight and the haematological parameters determined.

Anti-Trypanosomal potential of momordica balsamina Linn Fruit Pulp extract against Trypanosoma brucei brucei Infection

The search for new trypanocides has not been keenly pursued due to high cost of design and development with no promise of financial returns. Momordica balsamina fruit pulp extract was screened for antitrypanosomal activity in experimental T. brucei brucei infection in rabbits. The extract was administered prior to parasite inoculation; 24 hours post parasite inoculation and on establishment of infection. The treatment was by oral administration of the extract at 500 mg/kg body weight for 14 consecutive days. Parasitaemia was monitored daily while body weight and packed cell volume (PCV) were determined before commencement of studies and subsequently at weekly intervals for 28 days. TThe result showed a significant (P0.05) delay in the establishment of T. b. brucei infection in rabbits treated at 24 hours post parasite inoculation. Packed cell volume also increased significantly (P0.05) in all treated groups when compared to the untreated group (control). This was less in the group treated on establishment of infection. Administration of the extract to the curative group resulted in body weight gain. The other groups suffered weight loss. The infected but not treated group died at day 39 post infection while those treated before parasite inoculation; 24 hours post parasite inoculation; and on the establishment of infection survived for 45 days;53 days; and 61 days respectively. We conclude that M. balsamina pulp extract reduces anaemia in experimentally infected rabbits

Assessment of renal function in malaria patients in Minna, North Central Nigeria

Establishment of prevalence of malaria-associated renal impairment in Nigeria is important for proper prognosis and management of malaria and its associated complications. Using biuret method for protein estimation; alkaline picrate-slot method for creatinine and urea estimation; and flame photometry and titrimetric method for electrolytes estimation; selected kidney function parameters which included proteinuria; serum levels of urea; creatinine and electrolytes were determined in 169 malaria patients and in 58 individuals without malaria. Data obtained were analyzed using one-way analysis of variance to compare variation among malaria patients and individuals without malaria; Duncan multiple range test to compare variation among means; and correlation matrix to evaluate correlation between the parameters measured. Proteinuria in malaria cases differed significantly (p 0.05) from individuals without malaria; and a positive correlation existed between proteinuria and parasitaemia. There was no significant difference (p0.05) in the creatinine levels of malaria patients and those without malaria. It is concluded that there is a form of renal impairment associated with malaria infection in Minna irrespective of age and sex

Architecture of the Trypanosoma brucei nucleus during interphase and mitosis.

The structural basis of mitosis, spindle organisation and chromosome segregation, in the unicellular parasite Trypanosoma brucei is poorly understood. Here, using immunocytochemistry, fluorescent in situ hybridisation and electron microscopy, we provide a detailed analysis of mitosis in this parasite. We describe the organisation of the mitotic spindle during different stages of mitosis, the complex ultrastructure of kinetochores and the identification of a potential spindle-organising centre in the mitotic nucleus. We investigate the dynamics of chromosome segregation using telomeric and chromosome-specific probes. We also discuss the problems involved in chromosome segregation in the light of the fact that the T. brucei karyotype has 22 chromosomes in the apparent presence of only eight ultrastructurally defined kinetochores.

Evidence for novel cell cycle checkpoints in trypanosomes: kinetoplast segregation and cytokinesis in the absence of mitosis.

Trypanosoma brucei has a single nucleus and a single kinetoplast (the mitochondrial genome). Each of these organelles has a distinct S phase, which is followed by a segregation period, prior to cell division. The segregation of the two genomes takes place in a specific temporal order by interaction with microtubule-based structures, the spindle for nuclear DNA and the flagellum basal bodies for the kinetoplast DNA. We used rhizoxin, the anti-microtubule agent and polymerisation inhibitor, or the nuclear DNA synthesis inhibitor aphidicolin, to interfere with cell cycle events in order to study how such events are co-ordinated. We show that T. brucei cytokinesis is not dependent upon either mitosis or nuclear DNA synthesis, suggesting that there are novel cell cycle checkpoints in this organism. Moreover, use of monoclonal antibodies to reveal cytoplasmic events such as basal body duplication shows that some aphidicolin treated cells appear to be in G(1) phase (1K1N) but have activated some cytoplasmic events characteristic of G(2) phase (basal body segregation). We discuss a possible dominant role in trypanosomes for kinetoplast/basal body segregation in control of later cell cycle events such as cytokinesis

Glutathione reductase (EC 1.6.4.2.) in experimental trypanosomiasis.

The activity of glutathione reductase (GHSR) in extracts of kidney, liver and testis of rats infected with Trypanosoma congolense decreased with every wave of parasitemia. The implications of these observations as they relate to the risk of oxidative stress are discussed.