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The systemic toxicity of a trimethylbenzene isomer and constituent of C9 aromatic solvents (1,3,5-trimethylbenzene, 135-TMB) was studied in Sprague-Dawley rats following a 90-day oral gavage exposure to 0, 50, 200 and 600 mg/kg/day. No statistically significant effects on body weight, body weight gain or food consumption were observed at study termination. Treatment-related changes in clinical chemistry parameters at the end of the 90-day dosing period were limited to small, but statistically significant, increases in phosphorus levels in high dose males and females. Liver enlargement in high dose male/female rats was considered an adaptive response as this was reversible and was not associated with histopathological lesions or increased liver enzyme markers indicative of liver damage. Kidney weight changes were limited to a small, but statistically significant, increase in relative weights in high dose males. This was not associated with histopathological lesions and thus not considered toxicologically relevant. Overall, the No-Observed-Adverse-Effect-Level (NOAEL) was the highest concentration tested (600 mg/kg/day). The results of the present study are relevant for assessing the risk of trimethylbenzenes through the oral route of exposure and provide a basis for the development of provisional screening values for trimethylbenzene isomers while avoiding the uncertainty associated with route-to-route extrapolation.

The aim of this study was to investigate the leucopoetic and testosterone levels of rats administered sub- chronic methanolic leave extract of Dracenea arborea. Acute toxicity study of the extract was performed using male rats. A total of120 maleratsweighing140±14.14 gwereusedfor the sub-chronic study divided into four groups. Groups B, C, and D were given 50, 100, and 500 mg/kg body weight, bw of the extract, respectively, while group Awhich served as the con- trol was given normal saline at the dosage of 10 ml/kg bw. Both the extract and the normal saline were given daily for 91 days using the oral route. The parameters assessed in the sub-chronic study were—testosterone levels (TesL), total leu- cocyte counts (TLC), differential leucocyte counts, and his- tology of the testes. The mean TesL of the treated groups showed significant increase (p

The present study was undertaken to evaluate the efficacy of an ointment of honey bee and Fagopyrum esculentum Moench in the management of large dermal wound in a male rabbit wounded accidently. The wound was covered entirely by honey and then the fine powder of buckwheat grains was added. The treatment was applied once a day until complete epithelization has taken place. The results showed a complete resorption of inflammatory exsudate of wound at 4th day. The percentage of wound contraction has shown a rate of 5.55% at the 4th, it has risen to 32.22 and 71.48% at days 7 and 11 respectively to register 99.53% at the 26th days. The epithelization period was 27 days with a mean healing rate of 200 mm2 day-1. The study concludes that the ointment of honey and buckwheat stimulate the healing process in dermal wounds particularly in term of wound contraction. Other studies are underway to understand the possible implication of some amino acids as lysine, proline and glycine presented in buckwheat in the collagen synthesis process.

Averrhoa carambola L., a species belonging to the Oxalidaceae family, is associated with neurological symptoms in individuals with renal diseases. The objective of this work was to accomplish a preclinical toxicological study of the hydroalcoholic extract (HE) from A. carambola leaves. Wistar rats and Swiss mice, both male and female, were used in these experiments. The rats were used in the acute toxicity assessment, with the extract administered at doses of 0.1 to 8.0 g/kg (oral route), and 0.5 to 3.0 g/kg (via intraperitoneal route). The mice received the extract in doses of 0.5 to 5.0 g/kg (via oral and intraperitoneal routes) and were observed for 14 days. Rats were also used in the sub-chronic toxicity evaluation, and divided into three groups (n=10): control group, HE 0.125 g/kg and HE 0.25 g/kg. These animals received HE for a 60 day period, at the end of which a macroscopic analysis of selected organs was performed with biochemical analysis of the blood. The acute toxicity assessment revealed that the HE of A. carambola L. presented low toxicity in the mice and rats. Furthermore, no signs of toxicity were present in the sub-chronic assessment. Keywords: Averrhoa carambola L., Oxalidaceae, acute toxicity, sub-chronic toxicity African Journal of Biotechnology Vol. 12(40), pp. 5917-5925

A total of 40 Wistar rats, weighing 130-140 g, were allocated randomly into four groups. They were orally administrated with 0 (control group, GC), 64.18 (low-dose group, GL), 128.36 (middle-dose group, GM), and 256.72 (high-dose group, GH) mg aluminum chloride (AlCl3) per kilogram body weight in drinking water for 120 days. Kidney coefficient and aluminum (Al) concentrations in blood and kidney were determined, and renal autopsy and histological changes were observed. The results showed that kidney coefficient in all Al-treated groups were obviously lower than that in GC (P

The purpose of this study has been to describe test procedures for measuring the (sub)chronic effects of chemicals on the freshwater cyclopoid Eucyclops serrulatus. To this end we have adapted the setting of the standard full life-cycle protocol of the marine harpacticoid A. tenuiremis to E. serrulatus. We have tested the effects of 4 different diets, two temperatures and two rearing volumes on the survival, development, reproduction and population growth rates of this species. Our results have highlighted that full life-cycle tests can be run using 2 mL-glass vials, a diet consisting of a mixture of living cells of Chlorella sorokiniana and Scenedesmus quadricauda, at either 25 degrees C (test duration: 42 days) or 18 degrees C (test duration: 51 days). However, the best performance in terms of survival, development, reproducibility and population growth rates with this species was obtained at 18 degrees C, albeit with significantly longer test duration. Subchronic tests in 2 mL-glass vials with the mixture microalgal diet at both temperatures are available options if considered appropriate for the objectives of a given study. In particular, developmental tests from nauplius to copepodid may profitably be performed in about 11 days at 18 degrees C and in 6 days at 25 degrees C. Under the same test conditions, subchronic tests from copepodid to adult may be run in 19 days at 18 degrees C and in 16 days at 25 degrees C. (C) 2017 Elsevier Ltd. All rights reserved.

Cigarette smokers typically display impulsivity by preferring immediate rewards over larger, delayed rewards at shorter delays than do non-smokers. Suggesting causality, nicotine injections in rats increase the choice for an immediate reward over a larger, delayed reward.To examine the generality of this latter effect, the present study employed a delay-discounting task to determine if acute and sub-chronic nicotine will also increase impulsive choice when subjective reward value is manipulated by changes in the probability, rather than magnitude, of reward.Rats were presented with two levers, one of which delivered an immediate water reward on half of the trials, while the other lever delivered the same reward on every trial, but only after one of five increasing delays.Acute injections of 1.2 mg/kg, but not 0.8 mg/kg, of nicotine increased the preference for the immediate (but less certain) reward lever at intermediate delays. Moreover, twice-daily injections of 0.8 mg/kg of nicotine for 6 days progressively increased the preference for the immediate reward. Latency to make the first response on each trial was not affected by nicotine.The similar increases in impulsive choice produced by both acute and sub-chronic nicotine in delay-discounting paradigms whether subjective reward value is manipulated by changes in reward magnitude or probability suggests that nicotine may be increasing what is common to these paradigms, namely delay discounting. Whatever the mechanism, these data indicate that both acute and sub-chronic nicotine may help develop and maintain an addiction by increasing impulsivity.

Objective: Gibberellic acid (GA3) is a plant growth regulator (PGR), largely used in agriculture in many countries including Egypt. The purpose of this study was to investigate the effects of sub-chronic toxicity (8 weeks) of GA3 on testicular function and structure in adult albino rats, and to determine the effects of withholding of GA3 on the affected parameters for another 8 weeks of follow up period. Material and Methods: Forty adult male albino rats were equally divided into four groups; the first group was used as a negative control, the second group received 1ml of 1N NaOH (positive control group), the third group received 75 ppm of GA3 daily in drinking water for 8 weeks (GA3 group), and the last group received the same treatment as the third group for 8 weeks then was left without any treatment for another 8 weeks (recovery group). At the end of the experimental period, rats were sacrificed and the testes were examined by light and transmission electron microscope for detecting the histopathological changes, examination of sperm viability & count and measuring testicular malondialdhyde. Testicular sections were examined immunohistochemically for the detection of the anti-apoptotic Bcl-2 protein. Results: In GA3 treated group, histopathological changes were in the form of regression in spermatogenesis using light microscope, while electron microscopic examination revealed apoptotic changes in the Leydig cells and distortion of the adluminal compartment. These changes were accompanied by significant elevation in testicular malondialdehyde, while Bcl-2 showed week immunoreactions in the layers of spermatids. After the 8 weeks of GA3 withholding, significant improvement in the testicular function and structure with improvement of Bcl-2 immunoreaction. Conclusion: From the previous results, it can be concluded that GA3 exposure can induce reversible toxic changes in the testes of adult albino rats on sub-chronic exposures.

Adult cats show limited spontaneous locomotor capabilities following spinal transection, but recover treadmill stepping with body-weight-supported training. Delivery of neurotrophic factors such as brain-derived neurotrophic factor (BDNF) and neurotrophic factor 3 (NT-3) can substitute for body-weight-supported training, and promotes a similar recovery in a shorter period of time. Autologous cell grafts would negate the need for the immunosuppressive agents currently used with most grafts, but have not shown functional benefits in incomplete spinal cord injury models and have never been tested in complete transection or chronic injury models. In this study, we explored the effects of autologous fibroblasts, prepared from the individual cats and modified to produce BDNF and NT-3, on the recovery of locomotion in acute, sub-chronic and chronic full-transection models of spinal injury. Fourteen female cats underwent complete spinal transection at T11/T12. Cats were separated into four groups: sham graft at the time of injury, and BDNF and NT-3 producing autologous fibroblasts grafted at the time of injury, 2 weeks after injury, or 6 weeks after injury. Kinematics were recorded 3 and 5 weeks after cell graft. Additional kinematic recordings were taken for some cats until 12 weeks post-graft. Eleven of 12 cats with neurotrophin-producing grafts recovered plantar weight-bearing stepping at treadmill speeds from 0.3 to 0.8 m/sec within 5 weeks of grafting, whereas control cats recovered poor quality stepping at low speeds only (≤ 0.4 m/sec). Further, kinematic measures in cats with grafts were closer to pre-transection values than those for controls, and recovery was maintained up to 12 weeks post-grafting. Our results show that not only are autologous neurotrophin-producing grafts effective at promoting recovery of locomotion, but that delayed delivery of neurotrophins does not diminish the therapeutic effect, and may improve outcome.

Objective To access the toxicity of forsythin from Forsythia suspensa leaves and evaluate its safety. Methods Acute toxicity was determined by oral administration of a single dose of 18 100 mg/kg forsythin in NIH mice. Sub-chronic toxicity was evaluated by oral administration of several doses of forsythin for 30 days at does of 0, 540, 1 620, and 6 480 mg/kg in SD rats. Results In the acute toxicity study, mortality was not observed after 14 days. In addition, clinically relevant adverse effects, or variations in body weight or food consumption were not observed. Similarly, after 30 days in the sub-chronic toxicity study, no mortality or significant toxicological effects such as decreased food consumption, body weight, biochemical parameters and vital organs etc. were noticed. Conclusion The results revealed that the forsythin from Forsythia suspensa leaves has low or no toxicity via oral administration, and therefore is suitable for further development and applications.

Atorvastatin is considered to be one of the most commonly used of all statins antihyperlipidemic drugs despite the fact that there is much controversy about its safety. Its therapeutic use becomes severely limited by the hazards of inducing myotoxicity. Curcumin is one of the safe spices that have chemoprotection and cytoprotection effects against endogenous and exogenous noxious stimuli. This study investigates the effect of curcumin on atorvastatin sub-chronic use - induced myotoxicity in rats by the assessment of serum creatinine phosphokinase, lactic acid dehydrogenase, myoglobin, troponin, potassium, creatinine and histopathological changes of skeletal, smooth and cardiac muscles by light and electron microscope examination. Eighty adult albino rats were divided into four groups: each group consists of twenty rats. The control group received water, the second group received atorvastatin, third group received curcumin and the fourth group received curcumin with atorvastatin for 90days by gastric gavage. The prolonged use of atorvastatin induced significant abnormalities of all myotoxicity biomarkers associated with histopathological and ultrastructural changes in the different types of the muscles. Co-administration of curcumin with sub-chronic use of atorvastatin led to an improvement in myotoxicity manifestations.

Memory impairment is a common disorder in diabetes mellitus which is associated with hippocampal neuronal apoptosis. The present study was conducted to examine the effect of one-week intraperitoneal (ip), administration of aminoguanidine (AG) on passive avoidance learning (PAL) and Bcl-2 family gene expression in the hippocampus of rats. Sixty male rats were divided into ten groups: non-diabetic/diabetic animals with/without AG (50, 100, 200 and 400 mg/kg, ip) treatment for one week. PAL and Bcl-2 family genes were examined. AG (100 and 200 mg/kg) improved both memory and Bax, Bak, Bcl-2 and Bcl-xl deficiency significantly in diabetic rats. AG treatment also ameliorated the diabetes-induced changes in (Bcl-2+Bcl-xl)/(Bak+Bax) ratios considerably. These results propose that one-week ip administration of AG may recover the deficit cognition in diabetic rats via enhancing (Bcl-2+Bcl-xl)/(Bak+Bax) proportions (Tab. 2, Fig. 4, Ref. 55).

Background: Clinacanthus nutans (C. nutans) Lindau (family Acanthaceae) is a shrub widely cultivated in the South East Asia region, including Malaysia. It has been traditionally used for treatment of various ailments including pain-mediated diseases. Various pharmacological activities of C. nutans have been reported except for its pain-relieving activity. This study was performed to evaluate the acute and sub-chronic oral toxicity of the methanol extract of Clinacanthus nutans (MECN) in male and female mice.Methods: In the acute toxicity study, a single dose of 5000 mg kg-1 of body weight MECN was administered orally, and was monitored for 14 consecutive days. In the sub-chronic toxicity study, the MECN was administered orally at doses of 50, 500, and 2500 mg kg-1 day-1 for 28 days. Results: Results showed that there were no clinical signs of toxicity, mortality and body weight changes in both acute and subchronic toxicity studies. There were no significant differences in relative organ weight, haematological parameters, and biochemical parameters; except for the creatinine level, which indicated significant (p

Nephelium lappaceum is a tropical fruit native to Malaysia. The rind of N. lappaceum, is having extremely high antioxidant and free radical scavenging activities. The ethanol extract from the rind of Nephelium lappaceum was evaluated for acute and sub-chronic toxicity study in Sprague Dawley rats. In the acute study, a single oral administration of N. lappaceum rind extract (50, 200, 1000 and 2000 mg kg⁻¹) was administered to rats for 14 days. In the sub chronic toxicity study, the extract was administered to rats (500, 2000 mg kg⁻¹) for 28 days. There was no mortality, or adverse effects observed in rats. There was no significant difference observed in relative organ weights and the biochemical analysis (serum urea, creatinine, ALP, AST and total protein). Histological observation of liver and kidney also did not reveal any significant changes. In conclusion, present study showed that the lethal dose of ethanol extract of Nephelium lappaceum rind is more than 2000 mg kg⁻¹ and there is a huge margin of safety for the therapeutic use. No-observed-adverse-effect-level (NOEL) of the extract is considered to be up to 2000 mg kg⁻¹ day⁻¹ for 28 days in rats.

There is an increasing belief that organophosphorus compounds (OPCs) impair glucose homeostasis and cause hyperglycemia and diabetes mellitus. The present study was undertaken to investigate the putative diabetogenic effect of sub-lethal and sub-chronic exposure to paraoxon (POX), an extremely hazardous OPC used in pesticides. The effect of paraoxon on streptozotocin-induced diabetic rats was also examined. Each rat was injected with 100 nmol of POX 5 days per week for 6 weeks. Blood glucose levels and red blood cell acetylcholinesterase activity were measured weekly. Biochemical analysis and morphological studies were performed at the end of the experiment. The results revealed that POX neither induces nor exacerbates diabetes mellitus in experimental rats. Liver and kidney/body weight ratios revealed statistically insignificant differences when compared with controls. Biochemical analysis of urine samples showed a small but not significant increase in protein level in all groups. Urine bilirubin was significantly higher in the diabetes + POX group when compared with the control group. The number of blood cells in urine was significantly higher in the POX-treated group compared with the control group. Hyperglycemia was noted in the diabetes and diabetes + POX groups, but neither in the saline control nor in POX-treated normal rats. Electron microscopy of POX-treated pancreas did not show any morphological changes in beta cells. These results suggest that POX does not cause diabetes mellitus at sub-lethal sub-chronic exposure. Copyright © 2012 John Wiley & Sons, Ltd.

Despite the wide spread use of Securidaca longepedunculata in all parts of Africa, not much has been reported in the literature about its toxicity. The few reports available are in connection with its trypanocidal and insect toxicity where it is used as a stored grain preservative. In our investigation, it was discovered that intraperitoneal administration (i.p.) of limit dose of 2.83 mg/kg of the extract produced neither mortality nor acute signs of toxicity through out the 48 hours period of observation. In the sub-chronic toxicity study however, i.p. administration of the extract to rats produced dose dependent multiple organ toxicities in the kidneys and the liver. The rats showed signs of respiratory distress and muscle paralysis with a stretching of the hind limbs at the point of death. The extracts also significantly (p

Clinical studies have suggested that estrogens may affect the symptoms of schizophrenia. The novel object recognition task (NORT) in female rats treated with sub-chronic phencyclidine (PCP) was used as an animal model of the cognitive deficits in schizophrenia. The current studies investigated whether chronic estradiol (E) could alleviate sub-chronic PCP-induced cognitive deficits in the NORT. Adult Sprague-Dawley rats were ovariectomized (ovx) and treated with either sub-chronic PCP (2 mg/kg bidaily i.p. for seven days), or with 0.9% saline and their object recognition memory was tested with the NORT using an acquisition trial, 1 min inter-trial interval, and retention trial. Sub-chronic PCP administration did not reliably affect behavior in the acquisition trial but significantly impaired object recognition in the retention trial for 1-2 and 27-29 weeks. Ovx females spent significantly (p

The effects of medium term administration of crude Diospyros mespiloformis root extracts on some biochemical parameters were investigated in mice. Forty mice were divided into two groups of twenty animals each. Animals in group I were gavaged with the root extracts at 400mg/kg/body weight for five weeks. Group II received normal saline (0.09%w/v NaCl) and served as controls. Whole body weights, fresh organ weights, packed cell volume (PCV) and some serum biochemical parameters were analysed using standard methods. Results showed minimal variation in whole body weights and packed cell volumes of animals given the extracts. Also values for some organ weights, triacyglycerides (148.25± 2.78 mg/dL), and Alkaline Phosphatase (41.50± 1.71 mg/dL) were not significantly (p > 0.05) different between test and control animals in the final week. However, heart (0.74%), lungs (4.43%), glucose (113.92 ± 2.43 mg/dL), total proteins (4.75 ± 1.25mg/dL), Aspartate Transaminase (40.50 ± 1.50 µL) and Alanine Transaminase (43.52 ± 4.50µL), were significantly (p < 0.05) different between the animals administered D. mespiliformis and controls. These results are early indications that long term consumption of D. mespiliformis could predispose to adverse tissue effects.

A three months as sub chronic study of diazinon on male wild pigeons (Culumba livia gaddi) by oral intubation were done. The study consisted of four groups each with six pigeons: A(high dose 0.3 mg), B(intermediate dose of 0.6 mg), C(low dose 1.2 mg) and D(untreated control). Clinical observation of treated pigeons did not show significant changes only the birds appeared to the quite after dosing for short time.

Despite the hepatotoxic effects of Rifampicin (RIF), its use is inevitable in the management of tuberculosis. No satisfactory treatment is available for prevention of this adverse effect. This study was undertaken to evaluate the protective effect of Nigella sativa extract (NSE) against Rifampicin induced sub-chronic hepatotoxicity. Male wistar rats were divided in 4 groups of 8 each and received vehicle, RIF (100 mg/ kg), RIF (100 mg/kg)+NSE (250 mg/kg) or RIF (100 mg/kg)+NSE (500 mg/kg) orally respectively for 28 days. Blood was withdrawn at day 14 and 28 for estimation of circulatory liver markers and anti-oxidant levels. At the end of the experiment histopathological study and estimation of SOD, CAT, GSH and LPO in liver samples was done. Pre-treatment of NSE produced significant hepatoprotection by decreasing the level of serum Alkaline phosphatase (ALP) (p

We investigated the effect of oral cadmium intoxication on the antioxidant/prooxidant status in serum and heart. Wistar rats, separated into four groups, that received: (1) tap water for 60 days (control); (2), (3) and (4) Cd 2+ (15 ppm)-containing water, during 15, 30 and 60 days, respectively. Lipoperoxidation increased in serum and heart of group 4. Circulating paraoxonase-1 activity was higher in groups 2 and 3. Protein carbonyl-groups increased while total and reduced glutathione levels decreased in the heart after 15 days of cadmium intoxication. Cardiac catalase activity was higher in groups 3 and 4 but glutathione peroxidase activity diminished in the heart of all poisoned groups. Superoxide dismutase transcript levels as well as Nrf2 expression also increased in the heart of groups 2 and 3, while gp91phox and p47phox mRNA levels rose only in group 3. We suggest cadmium intoxication modifies antioxidant/prooxidant ratio in serum and heart in a time-of-exposure-dependent way.

Stress facilitates pain perception and sensitizes pain pathways, but the underlying mechanism is still unclear. The purpose of this study was to investigate whether the activation of 5-hydroxytrypt...

Several studies have tested nicotinic receptor ligands in the 5-Choice Serial Reaction Time Task (5-CSRTT) with varying results. Some investigators have increased attentional demands by modifying task parameters or using aged or poor performing rats to observe treatment effects. This study examined the alpha4beta2 nicotinic agonist ABT-594 in the 5-CSRTT using a variety of manipulations to determine optimal conditions for observing enhancement. ABT-594 had no effect in drug-naïve adult rats that self-initiated trials. Constant trial presentation decreased accuracy and omissions, with the latter significantly attenuated by acute administration of ABT-594 (0.019-0.062 micromol/kg). Sub-chronic treatment (0.019 micromol/kg) initially impaired drug-naïve subjects, but significant improvements in accuracy and decreased omissions were observed after 5 days of dosing. In 18-22 month-old rats, attentional demands were altered by interspersing blocks of trials with different stimulus durations. Acute ABT-594 (0.062 micromol/kg) enhanced accuracy performance in poor performing rats (70% accuracy) but not in those that performed well (80% accuracy), while omissions were decreased in both groups. Sub-chronic treatment with (0.019 micromol/kg) decreased omissions in all rats, but enhanced accuracy primarily in poor performing rats. These experiments demonstrate that an alpha4beta2 nicotinic agonist can enhance attention, but accuracy effects may only be observed under specific conditions. Moreover, a reduction in omissions was more reliably observed than improvements in accuracy, resulting in a net increase in signals successfully detected.

Background: Humans and animals can hear a wide range of sound frequencies. If the sense of hearing is impaired, both man and animal cannot fare well in their respective environments. Present study is aimed to investigate the behavioral effects following the sub-chronic noise stress of a rat species, Albino Wistar.Methods: The sound source consists of a set of speakers, GWINSTEK AFG-2000 series function generator and an amplifier. Sound levels and frequencies were monitored by B and K type 2250 sound level meter. Six adult Albino Wistars were exposed to sound frequencies of 1-20 kHz, at intervals of 1 kHz at LAeq of 70-80 dB for 5minute periods and their behavior was recorded. In the second test four adult rats were randomly divided into control and test groups. The test animals were exposed to noise of 7, 8, 9 and 10 kHz for 4hrs daily while keeping the control group in same room for same period of time without exposing to the sound. Locomotive activity, increase of defection and decrease of social activities, of rats was assessed by open field test (OFT). Anxiety and depressive behavior were monitored by elevated plus maze test (EPM) and tail suspension test (TST).Results: A different behavior in rats was observed in frequency range of 7-10 kHz. At the beginning of exposure, all rats were huddled in a group and then some were frozen into motionless stance. A less time spent and less number of entries in open arm was noticed in test sample compared to the controls in the EPM test. A tendency to move to open field compared to controls was identified in OFT. The TST revealed that a significant increase in immobility time, which indicates a depression like behavior of noise stressed rats compared to controls.Conclusions: According to the study the most effective noise frequency range for rats is 7-10 kHzl.

In this study, we examined the effects of low levels and sub-chronic exposure to methylmercury (MeHg) on butyrylcholinesterase (BuChE) activity in rats. Moreover, we examined the relationship between BuChE activity and oxidative stress biomarkers [delta-aminolevulinic acid dehydratase (delta-ALA-D) and malondialdehyde levels (MDA)] in the same animals. Rats were separated into three groups (eight animals per group): (Group I) received water by gavage; (Group II) received MeHg (30 microg/kg/day) by gavage; (Group III) received MeHg (100 microg/kg/day). The time of exposure was 90 days. BuChE and ALA-D activities were measured in serum and blood, respectively; whereas MDA levels were measured in plasma. We found BuChE and ALA-D activities decreased in groups II and III compared to the control group. Moreover, we found an interesting negative correlation between plasmatic BuChE activity and MDA (r = -0.85; p < 0.01) and a positive correlation between plasmatic BuChE activity and ALA-D activities (r = 0.78; p < 0.01), thus suggesting a possible relationship between oxidative damage promoted by MeHg exposure and the decrease of BuChE activity. In conclusion, long-term exposure to low doses of MeHg decreases plasmatic BuChE activity. Moreover, the decrease in the enzyme is strongly correlated with the oxidative stress promoted by the metal exposure. This preliminary finding highlights a possible mechanism for MeHg to reduce BuChE activity in plasma. Additionally, this enzyme could be an auxiliary biomarker on the evaluation of MeHg exposure.

Objective We explored the role and molecular mechanism of Microcystin-LR (MC-LR) in hepatocarcinogenesis.

Background: Few articles have linked the consumption of green tea to certain liver diseases but several articles have disputed these assertions and the consumption of green tea has been on the increase. Aims: The effects of oral administration of green tea on the liver of Wistar rats were studied in order to compare biochemical findings with histological findings. Materials and Methods: 36 male and female Wistar albino rats were grouped into 6, consisting of 6 rats in each group. They were given 1%, 2%, 3%, 4% and 5% concentration of green tea in tap water for 42 days. The 6 th group was on normal diet and received 0% of the tea. Their blood samples were analyzed for total and conjugated bilirubin, total protein, albumin, globulin, alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase. The liver tissues were also processed for histological examination. Results: The liver tissues were essentially normal and similar to the control tissues. The biochemical parameters studied were also normal and similar to the results obtained from the control animals. Conclusion: Sub chronic consumption of green tea has no injurious effects on the liver of Wistar rats.

Cadmium (Cd) accumulation and elimination were assessed in the tissues of the clam R. philippinarum at four experimental concentrations (control, 10, 20, 100, and ) over an exposure period of 2 weeks and an elimination period of 1 week. Cd accumulated in the digestive gland, gill, and residual clam tissues, and accumulation increased with time of exposure and concentration (100 and ). After 2 weeks of Cd exposure, the order of Cd accumulation in tissues was gill > digestive gland > residual tissues. An inverse relationship was observed between concentration factor (CF) and exposure level, but the CF showed an increase with exposure time. During the depuration period, Cd concentrations in the digestive gland, gill, and residual tissues decreased immediately on the cessation of exposure, except in individuals at the concentration. The Cd elimination rate from tissues decreased in the order of digestive gland > gill > residual tissues during the depuration period.

The toxicity test of ammonium persulfate was conducted to ensure of its potential toxic effects according to the single-dose acute oral toxicity study (OECD Guideline 423) and 90-day repeated dose sub-chronic oral toxicity study guideline (OECD Guideline 408) for establishing national chemical management system, and matching in the Globally Harmonized Classification System (GHS) category. In acute oral toxicity study, pasty stool, perineal contamination and temporary body weight decrease were observed after dosing 1st and 2nd challenge (300 mg/kg body weight). All test animals were dead within 6 hours after dosing at 3rd challenge (2000 mg/kg body weight). Therefore, the GHS class of test substance is considered class 4. In sub-chronic toxicity study, body weight changes, food consumptions, hematological, biochemical and pathological examination did not show any noticeable and significant differences between the administered (5, 20, 80 mg/kg body weight) and control (vehicle only) group animals. Based on these results, the no observed adverse effect level (NOAEL) is considered above 80 mg/kg body weight.