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The study was conducted to assess the effect of zinc on erythrocyte osmotic fragility and hemogram of rats following chronic oral exposure to glyphosate-based herbicide (BUSHFIRE®) at daily doses of 14.4–750 mg/kg of glyphosate. The erythrocyte osmotic fragility, estimated as percentage hemolysis in hypotonic saline, was significantly (p

Objectives To assess the effects of zinc pretreatment on hepatorenal toxicity following chronic exposure to glyphosate-based herbicides in male rats. Methods Following zinc pretreatment (50 mg/kg and 100 mg/kg), 14.4 to 750 mg/kg of oral glyphosate (Bushfire® herbicide) was administered daily for 36 weeks. Thereafter, serum samples were obtained following jugular venipuncture. Liver and kidney samples were processed for histopathological examination. Results Serum aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase activity as well as levels of bicarbonate, calcium, creatinine were significantly increased following chronic exposure to Bushfire®. Serum levels of sodium, potassium, chloride, total protein, albumin, globulin and urea were unchanged. Moderate to severe coagulative necrosis of hepatocytes as well as glomerular and renal tubular necrosis were observed in herbicide-treated rats. Zinc pretreatment reduced the elevation of serum enzymes associated with hepatobiliary lesions, abrogated hypercalcemia and metabolic alkalosis, and mitigated serum accumulation of creatinine following Bushfire® exposure, but was ineffective in completely preventing histological lesions. Conclusion Chronic Bushfire® exposure in rats caused hepatorenal toxicity. The effects of exposure on serum parameters were ameliorated by zinc pretreatment, but the histopathological changes associated with toxicity persisted in milder forms in zinc-pretreated animals.

Objectives To assess the toxicopathologic effects of chronic exposure to the glyphosate-based herbicide Bushfire® on the pancreas of Wistar rats and the protective role of zinc. Methods We exposed the rats to daily doses of 14.4 to 750 mg/kg body weight of the glyphosate-based herbicide Bushfire® and to 50 or 100 mg/kg zinc, and measured blood glucose levels and serum insulin levels. Tissue samples were evaluated for histopathological alterations. Results Levels of both blood glucose and serum insulin increased in glyphosate-exposed rats, and moderate to severe degenerative changes were observed in both glandular pancreatic acinar cells and islets of Langerhans in all rats exposed to glyphosate. These effects were prevented by pretreatment with zinc. Conclusion Chronic exposure to glyphosate can alter pancreatic function and histoarchitecture, but zinc supplementation can mitigate these toxicopathologic effects.

Trypanosoma brucei, Federe strain, caused an acute infection in rats after intraperitoneal inoculation of 106 trypanosomes. Parasitemia occurred from day 3 post-infection (pi) with peak parasitemia from day 7 pi. Anemia was observed between days 7 and 11 pi. The serum triglyceride concentration was comparable with the control value on day 7 pi, but increased (P 0.05) significantly during the infection. It was concluded that the decreased hepatic contents of these lipids were consistent with the serum lipid concentration, which did not seem to favor lipid uptake by hepatocytes.

Background Erythrocyte swelling in non-ionic sucrose media and the subsequent osmotic lysis are influenced by mechanisms of regulatory volume adjustment and osmotic water permeability. Kinetics of transmembrane water and ion fluxes in varied physiologic states may determine the phenotype of erythrocyte osmotic fragility (EOF) and affect estimates of EOF. Methods Effects of sex, age, late pregnancy (third trimester) and lactation on the haemolysis of Sahel goat erythrocytes incubated in a series of hyposmotic non-ionic sucrose media were investigated. Results The fragiligram was sigmoidal in 72 (97%) out of 74 goats. Two male (3%) goats with low and high extreme median erythrocyte fragilities (MEF), had non-sigmoidal curves. The mean fragilities at osmolarities of 30-300 mosmol/L of sucrose and the mean osmolarities responsible for 10%-90% haemolysis (CH10-CH90) were not significantly different between males and non-pregnant dry (NPD) females, amongst the age groups and between pregnant or lactating and NPD female goats. The MEF (CH50) of the goats were at osmolarities of 126-252 mosmol/L (median of data: 171 mosmol/L) with a mean of 175.24±16.20 mosmol/L. Therefore, phenotypic homogeneity of EOF occurred with minor deviance, since EOF variables were not differentiated by sex, age, late pregnancy or lactation. Conclusions Physiologic states of the goat did not affect EOF phenotype in non-ionic sucrose media. Sigmoidal fragility phenotype seemed to be homogeneously conserved by osmoregulatory mechanisms not partitioned by sex, age, late pregnancy or lactation, but a minor non-sigmoidal curve might have occurred due to altered erythrocyte osmotic behaviour that would require further investigation.

A typical mammalian erythrocyte fragility phenotype (EFP) exhibits a sigmoidal curve of the dependence of fragilities (% haemolysis) on hypotonic saline concentrations, but the goat EFP tends to be hyperbolic. Physiological variation in median erythrocyte fragility (MEF) and the associated EFP of Sahel goats was investigated. Erythrocyte osmotic fragility (EOF) was determined in hypotonic saline using heparinized venous blood from 47 goats (23 males and 24 non-pregnant dry females) aged 1-4 years and weighing 18.87 ± 6.32 (9-30) kg. Packed cell volume (PCV), erythrocyte count and mean corpuscular volume (MCV) were also estimated. Low, medium and high EFP were based on MEF of < 7, 7-8 and > 8 g/L, respectively. MEF of all the goats was 7.5 ± 0.6 (5.9-8.4) g/L. Phenotypic drift from sigmoidal to hyperbolic EOF curve was observed at the lower and upper limits of the phenotypic variation. Frequencies of occurrence of low, medium and high EFP were not different (p > 0.05) between males and females. Fragiligrams of low, medium and high EFP separated at erythrocyte fragilities of 10-70% and saline tonicity of 7-8 g/L. The saline concentrations causing fragilities of 10-70% differed (p < 0.05) among the phenotypes. There was no correlation (r = -0.28, -0.30; p > 0.05) between MEF and MCV or PCV, and between PCV and MCV. In conclusion, phenotypic drift in EOF occurred in Sahel goats without influence by erythrocyte parameters and represented the physiological variability of EOF endpoint estimates that would serve as reference limits in evaluation of erythrocyte membrane defects. Keywords: Erythrocyte size, Median fragility, Osmotic fragility, Phenotypic drift, Sahel goat

Heparinised blood was exposed to osmotic lysis in hypotonic buffered saline to evaluate erythrocyte membrane stability. When K3 EDTA blood was used, it added more to the ionic content of blood than heparin. The influence of suspending media's ionic strength on the osmotic stability of Sahel goat erythrocytes was investigated by replacing the ionic saline with non-ionic saccharide (sucrose or glucose) and assessing the effect of using EDTA blood instead of heparinised blood.The erythrocyte osmotic fragility curve in saline was hyperbolic even when the ionic concentration was reduced by 50% with saccharides. Haemolysis was higher with EDTA than heparinised blood at saline concentrations of 90 and 150-180 mosmol/L. The fragility curve was sigmoidal and shifted to the left when saline was completely substituted with a saccharide. The non-ionic saccharides increased erythrocyte osmotic resistance linearly (r=0.88; p0.02) from median to minimal hyposmolarities (150-300 mosmol/L) and reduced the osmolyte concentration at median fragility by 36%. No effect occurred at30-120 mosmol/L and90% fragility; and saccharide concentrations were almost non-lytic at comparable saline concentrations evoking10% haemolysis. Fragilities were neither affected by period (30-60 min) of incubation nor the type of saccharide used.In this study, the variation in osmotic stability of caprine erythrocytes was linked to ionic strength of the suspending extracellular media which seemed to exert an influence through transmembrane ion fluxes and regulatory volume changes in erythrocytes.

Rabbits infected with Trypanosoma brucei brucei (Basa isolate) were intraperitoneally administered with vitamins C and E at 100 mg/kg and 10 mg/kg body weight, respectively, from day 7 before infection to day 12 post-infection (p.i.). Another group of rabbits were similarly infected, but received no vitamin treatment. The uninfected (control) rabbits were either untreated or treated with vitamins like the infected group. Treatment of the infected animals did not affect the onset and level of parasitaemia. On day 12 p.i., the anaemia tended to be ameliorated, but insignificantly, by the treatment. The infection increased (p0.05) serum urea and creatinine concentrations to similar levels in treated and untreated groups. However, the increase (p0.05) in alanine and aspartate transaminases in the untreated infected animals was prevented in the treated infected ones. Therefore, it seemed that the treatment with antioxidant vitamins boosted their storage in hepatic cells, but not in erythrocytes and glomeruli, to annul any cellular injury due to infection. It is concluded that this may be an indirect evidence that the hepatic damage may be principally due to oxidative injury.

The erythrocyte glutathione (GSH) concentrations of 210 Nigerian Sahel goats were 2.4–175.2 (46.5±36.4) mg/100 ml RBC or 0.1–7.3 (1.9±1.4) mg/gHb. The frequency distribution of the blood and erythrocyte GSH values were positively skewed, but the packed cell volume (PCV) and haemoglobin (Hb) concentrations were normally distributed. The erythrocyte GSH values in mg/100 ml RBC and mg/gHb were strongly correlated. Majority of the goat population (74.8%) had low or `deficient' erythrocyte GSH concentrations (≤60 mg/100 ml RBC). Sixteen animals with very low erythrocyte GSH values of 2.4–9.8 (6.9±2.9) mg/100 ml RBC were not anaemic and the anaemic goats with PCV of 17.0±0.9% had GSH concentrations of 3.5–97.5 (45.0±42.8) mg/100 ml RBC. The erythrocyte GSH values were not correlated with PCV or Hb, and anaemia. The biochemical basis for the low erythrocyte GSH concentrations is yet to be determined.

During acute Trypanosoma vivax infection of calves, produced by intravenous inoculation, the mean packed cell volume and red blood cell counts of the infected animals decreased significantly (P0.05) between Days 6 and 13 post-infection (pi). The moderately severe normocytic anaemia started to develop during the first wave of parasitaemia which occurred from Day 2 pi and peaked between Days 4 and 5 pi. The mean erythrocyte glutathione (GSH) concentration of the infected calves decreased significantly (P0.05) from 58.4 +/- 11.4 mg 100ml-1 red blood cells (RBC) on Day 0 pi to 44.5 +/- 12.8 mg 100ml-1 RBC on Day 5 pi. As the GSH values recovered on Day 6 pi and increased thereafter, another slight decrease (P0.05) in GSH concentration occurred on Day 12 pi at the second peak of parasitaemia followed by a significant (P0.05) increase to 79.1 +/- 14.6 mg 100ml-1 RBC on Day 13 pi. In the uninfected calves, the mean GSH values ranged from 47.7 +/- 7.0 to 60.8 +/- 6.8 mg 100ml-1 RBC. When washed, erythrocytes of the infected and uninfected calves were separately challenged with hydrogen peroxide. They produced comparable amounts of thiobarbituric acid reactive substances as a measure of by-products of lipid peroxidation. This suggested that the ability of the erythrocytes to prevent peroxidative injury was not reduced, because GSH regeneration was probably enhanced and the antioxidant capacity of the erythrocytes was maintained.

An experimental study of proximal duodenal obstruction (PDO) was performed on five Borno White goats by surgically placing an obstructing ligature on the duodenum 6 cm distal to the pylorus. Three intact goats were the first controls and another three goats, which were laparotomized (sham treated), were the second controls. Goats with PDO were weak, anorexic and passed very scanty to no faeces 24 h after PDO. Mean packed cell volume was higher during PDO, but not significantly increased (P>0.05). Total plasma protein concentration was significantly decreased (P

Five non-pregnant healthy Yankasa ewes were deprived of water for 10 d with only one watering period during hot dry weather. On d 5, the mean body weight significantly (P 0.05) and mean plasma globulin, sodium (Na), chloride, urea, creatinine and cholesterol concentrations and urea-to-creatinine and cholesterol-to-glucose ratios were significantly (P 0.05), mean PCV and plasma K, bicarbonate and glucose concentrations and albumin-to-globulin ratio still did not vary significantly. Significant increases (P

The effect of intravenous infusion of a solution of lactose-in-normal saline on the course of Trypanosoma vivax induced anaemia in Zebu yearlings was investigated. The animals were infected with 11 x 106 trypanosomes by jugular venipuncture and lactose-in-normal saline infusion started on day 6, post-infection (p.i). Three four-hourly doses of 0.5 g lactose/kg body weight were administered to each infected yearling in the experimental group daily for five days, while the infected control yearlings received no lactose-infusion. The experiment was terminated on day 13, p.i. Parasitaemia in the lactoseinfusedyearlings was scorable throughout the duration of experiment while parasites could not be detected in the blood of the infected control yearlings between days 7 and 9, p.i. Serum free sialic acids(FSA) concentration was also consistently higher in the lactose-infused yearlings than in the lactosefree ones. In the before lactose infusion (BL) period the PCV of the lactose-infused group dropped at asignificantly (P < 0.05) faster rate than in the lactose-free one. In the DL (during lactose infusion) period, the rate and magnitude of decline in PCV was significantly lower in the lactose-infused yearlings than inthe lactose-free animals. When lactose infusion was stopped (AL) the rate and magnitude of PCV decline became greater in the lactose-infused yearlings than in the lactose-free ones. It was thusconcluded that lactose ameliorated anaemia, by inhibiting the sequestration of desialylated erythrocytes from the blood stream of T. vivax-infected yearlings. This manifested in the reducedmagnitude and rate of decrease in PCV in the lactose-infused infected yearlings.

The effects of aqueous extract of Hibiscus sabdariffa calyces on haematology and pathological changes in some selected organs during experimental Trypanosoma congolense infection of rats were investigated. Three groups of rats were intraperitoneally infected with T. congolense (Karu stock). One group was administered with the aqueous extract and another given a solution of vitamin C in drinking water; the remaining infected group was left untreated. Data from these groups were compared with those of two groups of healthy rats, one of which was similarly treated with the aqueous extract. The experiment was terminated three weeks, post-infection (pi). The uninfected and infected rats administered the extract consumed the equivalent of 9.94 mg - and 9.61 mg ascorbic acid / 100g / day during the experiment. Consumption of the extract significantly (p

Eighty healthy adult albino rats of both sexes weighing 180-200g were used in two experiments to study the effects of oral calcium chloride treatment on the pathogenicity of Trypanosoma congolense infection. Experiment 1 was terminated at the peak of parasitaemia while experiment II was allowed to run a full course. In each experiment, forty rats were divided into four groups of 10 rats each, namely: A, uninfected untreated control; B, treated uninfected control; C, infected untreated and D, treated infected. Aqueous solution (10%) of CaCl2 was administered daily using stomach tube to each rat at 100mg/kg in groups B and D from 7 days before infection to the end of the study. Each rat in groups C and D was infected by intraperitoneal injection of 1x106 trypanosomes in phosphate buffered saline solution (pH 7.4) diluted donor rat blood. The infected untreated group exhibited higher (P T. congolense infection by delaying the onset of parasitaemia and reducing the levels of parasitaemia, accompanied anaemia as well as organ damage. Keywords : rats, Trypanosoma congolense , calcium chloride treatment, pathogenicity African Journal of Biomedical Research Vol. 8(3) 2005: 197-201

Les concentrations moyennes de glutathion érythrocytaire chez les bovins zébus Wadara nigérians (n = 32) étaient de 43,9 ± 11,7 mg/dl de globules rouges ou 1,96 ± 0,57 mg/gHb. Les valeurs du glutathion érythrocytaire exprimées dans ces deux mesures ont montré une corrélation (r = 0,85) l'une envers l'autre. L'hématocrite et les concentrations d'hémoglobine sont corrélés (r = 0,59, 0,52) avec les valeurs du glutathion érythrocytaire. La répartition des fréquences a montré que 37,5 % et 90.6 % des valeurs étaient respectivement inférieures aux 40 et 60 mg/dl de globules rouges. La concentration moyenne de l'acide ascorbique du plasma était de 0,7 ± 0,2 mg/dl. De faibles corrélations non significatives (r = -0,01, -0,36) ont été observées entre les concentrations du glutathion érythrocytaire et de l'acide ascorbique du plasma. En conséquence, les valeurs du glutathion érythrocytaire étaient affectées de façon significative par celles de l'hématocrite et de l'hémoglobine, mais pas par celles de l'acide ascorbique du plasma.

Une étude réalisée sur les concentrations de glutathion érythrocytaire des bovins zébus et Ndama nigérians a mis en évidence une variation allant de 40,8 à 135,1 mg/100 ml de globules rouges, avec une moyenne de 84,0 ± 25,4 mg/1o0 ml. On a observé une corrélation positive entre les concentrations de glutathion et l'hématocrite (r = 0,58, p0,05).

Trypanosoma brucei, Wamba strain, produced an acute infection in mice, and mortality was observed 2 days after the onset of parasitaemia which occurred 3–5 days postinfection. Anaemia was observed in the tail blood of the survivors. When washed erythrocytes from the heart blood were incubated in physiological saline containing 1.5% hydrogen peroxide, the erythrocytes of the infected mice produced significantly greater amounts of by-products of lipid peroxidation (measured as thiobarbituric acid reactive substances) than the erythrocytes of the control mice. This observation suggested that the infected mice may have a reduced ability in the prevention of free radical mediated lipid peroxidation in the erythrocyte membrane. It is concluded that peroxidative injury to the erythrocytes may contribute to the pathogenesis of anaemia in trypanosomosis.

A subchronic toxicity study was carried out to assess hepatic and renal functions of rats during oral exposure to glyphosate with zinc for the period of 8 weeks. Forty-eight Wistar rats used for the study were randomized into six groups of eight Wistar rats each, and each group had equal number of male and female Wistar rats. The Wistar rats administered with distilled water at 2 ml/kg body weight served as the control group (DW); others were administered with zinc at 50 mg/kg body weight (Z) group, glyphosate at 375 mg/kg body weight (G) group, a combination of zinc and glyphosate at 50 and 375 mg/kg body weight, respectively (Z + G), group, glyphosate at 14.4 mg/kg body weight (GC) group, and a combination of zinc and glyphosate at 50 and 14.4 mg/kg body weight, respectively (Z + GC), group. At the end of the study, blood samples were collected from each rats; from which, sera samples were obtained and assayed for total protein, albumin, alanine and aspartate aminotransferases, alkaline phosphatase, Na+, K+, Cl−, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathrm{HCO}_3^{-} $$\end{document}, Ca2+, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathrm{PO}_4^{-} $$\end{document}, urea and creatinine using autoanalyzer, and globulin was calculated. The albumin concentration was significantly high (p 0.05), and the relative changes were ameliorated by supplementation with zinc. The alkaline phosphatase activity was relatively low in GC group; however, supplementation with zinc in Z + GC group made it to be significantly high (p