Hepatoprotective and antioxidant effects of Bridelia retusa against carbon tetrachloride-induced hepatotoxicity

The aim of present study was to validate hepatoprotective and antioxidant activities of the bark of Bridelia retusa. The aqueous ethanol extract of B. retusa exhibited highest in vitro hepatoprotective effects as evident from the significantly reduced serum glutamate oxaloacetate transaminase (SGOT) and serum glutamate pyruvate transaminase (SGPT) into the incubation medium of rat hepatocytes with carbon tetrachloride (CCl₄), over the other organic extracts (chloroform, ethylacetate, and methanol). CCl₄ administered through subcutaneous injection produced a marked elevation in the serum levels of GOT, GPT, lactate dehydrogenase, alkaline phosphatase, bilirubin, thiobarbituric acid reactive substances, and decreased in the levels of reduced glutathione, superoxide dismutase, catalase, glutathione-S-transferase, glutathione reductase, glutathione peroxidase, and total protein content. The biochemical activities were normalized in the pretreatment of rats induced by CCl₄ with different doses (250 and 500 mg kg^?1) of the aqueous ethanol extract of B. retusa. Histopathological changes induced by CCl₄ were also significantly attenuated by aqueous ethanol extract of B. retusa treatment. The activity of the aqueous ethanol extract of B. retusa at the dose of 500 mg kg^?1 was comparable to the standard drug, silymarin (25 mg kg^?1). The overall data indicated that B. retusa possesses a potent protective effect against CCl₄-induced hepatic damage and oxidative stress.     

Toxicological attributes of plant chemicals and their biochemical impacts on cholinesterase and protein levels in relation with conventional insecticides against mosquito larvae of Karachi city

In order to control mosquito, different chemicals were applied against the larvae of Culex fatigans (Diptera Culicidae). The tested chemicals were Lambda cyhalothrin, chlorpyrifos, Azadirachta indica (Spindales meliaceae) neem extract, and Sueda monoica extract. All chemicals were found to have significant efficacy against Culex fatigans mosquito larvae. In terms of efficacy, the biochemical effects after treatment with such chemicals were found to vary. Total protein levels and acetylcholinesterase (AChE) activity were the parameters examined. Chlorpyrifos, Lambda cyhalothrin, and neem elevated AChE activity levels whereas the plant extract S. monoica decreased enzymic activity. Total protein levels were decreased by Lambda cyhalothrin and chlorpyrifos whereas protein was increased by neem extract and S. monoica.     

Larvicidal,repellent, and histopathologic effects of Citrullus colocynthis against the malaria vector

Abstract

This research is conducted to determine the larvicidal, repellent and pathological effects of fruit extracts of C. colocynthis on malaria vector mosquito, Anopheles stephensi Liston, 1901. The fruit water and ethanol extract of C. colocynthis were concentrated for larvicidal and repellent activities on human volunteer against An. stephensi. The temephos larvicide was tested as the positive control. A concentration of 300?mg/L had full-scale mortality and the most toxic effect. The LC₅₀ and LC₉₀ values of C. colocynthis water and ethanol extracts were 180and 283?mg/L, respectively. The LC₅₀ and LC₉₀ values of temephos were 0.2706 and 1.6932?mg/L, respectively. The ED₅₀ and ED₉₀ values of the plant extract were 0.2 and 1.3?mg/cm², respectively. Thin sections from treated larvae exhibited gross histopathologic effects of C. colocynthis fruit extracts on gut epithelial cell layer by vacuolization of foregut cuboidal and midgut columnar cells. This study suggested that the fruit extracts of C. colocynthis had significant larvicidal and repellent activity to be used as an ideal approach to control the malaria vector mosquito.     

Bromobenzene-induced hepatotoxicity in male rats: the protective effect of flaxseed

The metabolites of bromobenzene (BB) are hepatotoxic. The aim of this study was to determine the efficacy of different doses of flaxseed extract in alleviating BB-hepatotoxicity in male albino rats. Oxidative stress parameters, drug metabolizing enzymes, a pro-inflammatory marker, an apoptotic marker, and DNA fragmentation pattern were also assessed. Animals were divided into five groups treated by intragastric intubation as follows: control, BB-treated 460?mg?kg^?1?BW alone; three animal groups (III, IV, V) were treated concurrently with 460?mg?kg^?1 BB daily for 3 weeks and different doses of flaxseeds extract: 100, 200, or 300?mg?kg^?1?BW. Oral treatment of BB produced a significant decrease in activities of antioxidant enzymes superoxide dismutase and glutathione peroxidase and glutathione levels, while activities of glutathione reductase and drug-metabolizing enzymes; glutathione-S-transferases and cytochrome P450 were enhanced. BB-treatment resulted in enhanced production of nitric oxide and activation of COX-2 and caspase-3. Pre-treatment with different doses of flaxseeds extract prior and during BB-treatment protected liver against BB-induced hepatotoxicity. The lower dose of flaxseed extract (100?mg?kg^?1) was most effective one.     

Dry weight, carbon and nitrogen components of caprellid amphipods (Crustacea) inhabiting the Sargassumyezoense community of Otsuchi Bay, northeastern Japan

Dry weight (DW), carbon (C) and nitrogen (N) contents in four species of caprellids, Caprella danilevskii, C. subinermis, C. penantis R-type, and C. verrucosa, inhabiting Sargassumyezoense (Yamada) in Otsuchi Bay, northeastern Japan, were measured based on live specimens. In all species males tend to grow larger than females in pereonite II length, which is used as an indicator of body length, and have greater dry weight, carbon and nitrogen contents. All three parameters (DW, C and N) had highly significant relationships against pereonite II length. Regressions of female pereonite II length against the three parameters significantly differed from males in the four species. Average percentages of carbon and nitrogen contents of the total dry weight ranged from 30.82 to 32.21% and 5.82 to 6.86%, respectively. The carbon/nitrogen ratio tended to decrease against increasing pereonite II length, e.g., 7.2 to 4.3 in C. danilevskii. Received: 25 November 1996 / Accepted: 31 July 1997     

Protective effect of Tamarindus indica fruit pulp extract on collagen content and oxidative stress induced by sodium fluoride in the liver and kidney of rats

Fluorosis is a serious public health problem in many parts of the world. The generation of reactive oxygen species and lipid peroxidation has been considered to play an important role in the pathogenesis of chronic fluoride toxicity. The present study was undertaken to evaluate the protective effect of Tamarindus indica fruit pulp extract on the collagen content and oxidative stress in liver and kidney of fluoride-exposed rats. The first group served as control. The second group received 200 mg L^?1 of sodium fluoride through drinking water. The third and fourth groups received T. indica fruit pulp extract (200 mg kg^?1 body weight) alone and along with fluorinated drinking water respectively, daily by gavage for a period of 90 days. At the end of the experiment, blood samples were collected from all groups, and liver and kidney samples were taken concurrently. Levels of malondialdehyde and glutathione and the activities of superoxide dismutase and catalase were evaluated in the liver and kidney of experimental rats. Furthermore, level of hydroxyproline and histological examination of liver and kidney along with serum biochemical parameters were evaluated. In conclusion, fluoride was determined to cause adverse effects in rats, and the supplementation of tamarind to these animals alleviated the adverse effects of fluoride.     

Reproductive cycle of the brachiopodTerebratulina retusa on the west coast of Scotland

The reproductive cycles of two populations of the Recent articulate brachiopodTerebratulina retusa (Linnaeus) are described, based on samples taken between October 1985 and October 1986. Stereological analysis of the gonads revealed a single synchronised spawning event between late November and the end of January in the Firth of Lorn. In a second population, in Loch Fyne, spawning took place repeatedly throughout the spring and summer, with greatest spawning activity occurring in the late autumn.T. retusa from Loch Fyne were approximately three times more fecund than those from the Firth of Lorn. Productivity in the Clyde Sea area is approximately five times higher than in Firth of Lorn and higher fecundities and spawning frequencies of the Loch Fyne population are attributed, in part, to greater food availability. The initiation of gametogenesis appears to be mediated by the mobilisation of reserves stored in the outer mantle epithelium during the winter. Primary productivity increases dramatically in the spring and gametogenesis shows a corresponding increase.     

The effectiveness of katydid (<Emphasis Type="Italic">Neoconocephalus ensiger</Emphasis>) song cessation as antipredator defence against the gleaning bat <Emphasis Type="Italic">Myotis septentrionalis</Emphasis>

Many nocturnal katydids (Orthoptera: Tettigoniidae) produce intense calling songs, and some bat species use these songs to detect and locate prey. One Nearctic katydid species, Neoconocephalus ensiger, ceases or pauses singing in response to bat echolocation calls. We tested the hypothesis that song cessation is an effective defence against gleaning bats (i.e., bats that take prey from surfaces). We observed Myotis septentrionalis, a sympatric bat species that uses prey-generated sounds when gleaning, attack and feed on singing N. ensiger in an outdoor flight room. These bats demonstrated a preference for the calling song of N. ensiger over a novel cricket calling song when they were broadcast from a speaker in the flight room. Bats attacked speakers broadcasting N. ensiger calling song as long as the song was continuous and aborted their attack if the sound stopped as they approached, regardless of whether a katydid was present as a physical target on the speaker. Echolocation calls were recorded during attacks and no significant differences were found between continuous and interrupted song approaches for four call parameters, suggesting that M. septentrionalis may not use echolocation to locate silent prey. Therefore, song cessation by katydids in response to ultrasound is an effective defence against gleaning bats.     

In vitro assessment of natural plant extracts Withania somnifera,Cassia fistula,Saraca asoca,and Eucalyptus tereticornis using primary chicken embryo fibroblast cell culture treated with urea or mercuric chloride (II)

The present investigation examined the detoxifying potential of methanolic herbal extracts, namely the leaf and bark extract of Eucalyptus tereticornis, bark extract of Saraca asoca, Cassia fistula and Withania somnifera in vitro using primary chicken embryo fibroblast (CEF) cells against damaging effects of urea and mercuric chloride (HgCl) (II). The influence of 20?mM urea and 10?µM?HgCl (II) was determined on cell viability or proliferation of cells after treatment with plant extracts. Higher survival rate of primary CEF cells treated with higher concentrations of plant extracts was observed due to their protective ability against urea and HgCl (II). Cassia fistula bark extract (10?mg?mL^?1) was found to be most effective against 20?mM urea as it protects 90% of CEF cells whereas W. somnifera protects 86% of the cells within 24?h. After treating cells with10?µM HgCl, W. somnifera and E. tereticornis leaf extracts were found to be more effective among all other extracts as they protect approximately 86% and 70% of CEF cells, respectively, within 24?h. These results indicate that C. fistula and W. somnifera has the highest potential amongst all the five plant extracts for protecting CEF cells against damaging effects of urea and HgCl (II), respectively.     

Synthesis and antifungal property of N,N′-bis(trans-cinnamaldehyde)-1,2-diiminoethane and its derivatives

N,N′-bis(trans-cinnamaldehyde)-1,2-diiminoethane and its derivatives were designed and synthesized. Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (¹H-NMR) techniques were applied to characterize chemical structures, and the filter paper disk method was used to test for antifungal effect of the products against Aspergillus niger, Paecilomyces variotii, and Paecilomyces lilacinus. Chemical structure charaterization showed that the products are target compounds. Antimicrobial experiment results indicated that N,N′-bis(trans-cinnamaldehyde)-1,2-diiminoethane displayed reliable antifungal effects against three fungi, and its antifungal effect is close to that of cinnamaldehyde. N,N′-bis(p-methoxy cinnamaldehyde)-1,2-diiminoethane and N,N′-bis(p-chlorocinnamaldehyde)-1,2-diiminoethane also showed antifungal effects at a low concentration. Of the two, N,N′-bis(p-methoxy cinnamaldehyde)-1,2-diiminoethane appeared to be more suitable as it was more effective at higher concentrations against Paecilomyces.     

Larvicidal potential of different solvent extracts and oleanolic acid derivative from Coccinia indica against vector mosquitoes

The mosquito larvicidal activities of different solvent extracts (chloroform, ethyl acetate, and methanol) from the leaves of Coccinia indica were studied. Among the extracts tested, the methanol extract showed the highest larvicidal activity against early fourth instar larvae of Culex quinquefasciatus (LC₅₀?=?142?mg?L^?1), Aedes aegypti (LC₅₀?=?158?mg?L^?1) and Anopheles stephensi (LC₅₀?=?161?mg?L^?1) after 24?h of exposure period. The lowest larval mortality was observed with the ethyl acetate extract with the LC₅₀ values of 927, 872, and 730?mg?L^?1 against Cx. quinquefasciatus, Ae. aegypti, and An. stephensi, respectively. The chloroform extract showed the moderate larvicidal activity against the mosquito species tested with the LC₅₀ values from 446 to 546?mg?L^?1. A new triterpene was isolated from the methanol extract using bio-assay guided separation and identified as an oleanolic acid derivative by NMR, IR and mass spectral studies. The compound showed prominent larvicidal activity against Cx. quinquefasciatus, Ae. aegypti and An. stephensi with the LC₅₀ values of 5.6, 5.0, and 4.8?mg?L^?1, respectively. The results of the present investigation offer an opportunity for developing alternatives to rather expensive and environmentally hazardous organic insecticides.     

Effect of supplemented soybean (Glycine max L) diet and extracts on aluminum sulfate-induced genotoxicity

Aim of this study is to evaluate the protective role of Glycine max L. (soybean) against aluminum sulfate-induced genotoxicity. A diet containing 30% soybean and extracts obtained with various organic solvents were administered orally to male white Swiss mice prior to intraperitoneal injection of Al₂(SO₄)₃. Light microscopy was used for the examination of genotoxicity involving somatic cells, germ cells, and sperms. The main secondary metabolites contained in each extract were isolated and identified by chromatographic and spectral analyses. Administration of soy diet and extracts to the examined mice induced significant anti-mutagenic activity against bone marrow aberrations and spermatocyte and sperm abnormalities. At the end of this study, maximum protection was achieved using the methanolic extract (83% and 79%) followed by those obtained with chloroform (71% and 49%) and n-hexane (51% and 39%) for bone marrow aberrations and spermatocyte abnormalities, respectively. The observed activity of soybean extracts might be related to the main constituents isolated and identified. These main constituents were the isoflavone glycosides genistin and daidzin in addition to saponins (methanol extract), lignan matairesinol (chloroform extract), and β-sitosterol, unsaturated fatty acids as well as phospholipids (n-hexane extract). The results illustrated that soy extracts can be considered as alternative anti-mutagenic nutraceuticals and promising source for developing anti-mutagenic drugs.     

Protective effects of Flacourtia indica on doxorubicin-induced cardiotoxicity in rats

This study examined the cardioprotective activity of an ethanolic extract of Flacourtia indica (FI) against doxorubicin (DOX)-induced myocardial infarction (MI) in rats. Different phytoconstituents were identified by gas chromatography-mass spectroscopy. DOX is a chemotherapeutic agent which produces free oxygen radicals that result in serious dose-limiting cardiotoxicity. A DOX dose of 20?mg?kg^?1 body weight is used to bring significant changes in biochemical parameters, endogenous antioxidants, and moderate necrosis in the heart. The pretreatment with FI at two doses (250 and 500?mg?kg^?1) to DOX-treated rats significantly prevented the altered biochemical parameters such as serum marker enzymes serum glutamate-pyruvate transaminase, serum glutamate oxaloacetate transaminase, creatine phosphokinase, and lactate dehydrogenase, lipid profile such as low-density lipoprotein, very low-density lipoprotein, triglycerides, high-density lipoprotein, total cholesterol, and antioxidant parameters such as superoxide dismutase, glutathione, catalase, glutathione peroxidase, and malondialdehyde to near normal level. Serum urea, uric acid, and alkaline phosphate which are increased on DOX administration registered near normal values on pretreatment with FI. In conclusion, these data suggest that the ethanol extract of FI can prevent heart damage by DOX-induced MI in rats and this is likely mediated through its antioxidant activities.     

Inhibition of cyclooxygenase-2 protects against cocaine hepatotoxicity in CF-1 mice

Gender differences in oral cocaine hepatotoxicity have been observed and lipopolysaccharide (LPS) was shown to potentiate cocaine hepatotoxicity in male CF-1 mice. Since cocaine and LPS inflict hepatocellular damage through the production of harmful reactive species, the role of cyclooxygenase-2 (COX-2) in gender-dependent cocaine hepatotoxicity was investigated. COX-2 increases nitric oxide (NO) synthesis and pro-inflammatory mediator production in response to hepatocellular insult. Male and female CF-1 mice were orally administered 20 mg kg^?1 cocaine hydrochloride once daily for 7 days. Four hours after the last cocaine administration, the mice received 12 × 10⁶ EU LPS intraperitoneally (cocaine + LPS). Mice receiving meloxicam (7.5 mg kg^?1, p.o.), a selective COX-2 inhibitor, were pretreated 1 h before each cocaine administration. Meloxicam prevented liver damage in males produced by cocaine and cocaine + LPS as evidenced by microscopic appearance and biochemical indices equivalent to saline treatment. Acetaminophen (APAP) was administered orally as a positive control which shows no gender dependency and elicited a hepatotoxic response in both males and females. Altered biochemical indices suggest that COX-2 is activated, possibly to a greater extent in females versus males in APAP-induced hepatotoxicity. Meloxicam prevented all oxidative stress changes induced in males following APAP. The results suggest that the induction of COX-2 is responsible, in part, for cocaine hepatotoxicity with and without LPS exposure in male mice.     

Antibacterial and antimutagenic activitiy of extracts and essential oil from (Tunisian) Pistacia lentiscus

Aqueous and flavonoid-enriched extract as well as essential oil (EO) obtained from leaves of Pistacia lentiscus were assessed for antibacterial and antimutagenic activities. Antibacterial activity of different extracts and EO were evaluated against six bacterial strains. A marked inhibitory effect was observed against Salmonella typhimurium, whereas lower activity was observed against Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella enteritidis. EO showed significant inhibitory effects against Salmonella typhimurium, Salmonella enteritidis and Staphylococcus aureus. The antimutagenic activity of the different extracts against Aflatoxin B₁ (AFB₁) and sodium azide was demonstrated with the Salmonella typhymurium assay. The number of revertants per plate decreased significantly when the plant extracts were added to the assay system using Salmonella typhimurium TA100, TA98 and TA1535.     

Chemopreventive role of Indigofera aspalathoides against 20-methylcholanthrene-induced carcinogenesis in mouse

This investigation was undertaken to evaluate the chemopreventive effect of hydroalcoholic extract of Indigofera aspalathoides (HAIA) against 20-methylcholanthrene (20-MC)-induced carcinogenesis in mice. Tumor was induced by single subcutaneous administration of 20-MC (200 µg per mouse) in Swiss albino mice. After 24 h of 20-MC administration, HAIA was administered at the doses of 250 and 500 mg kg^?1 body weight orally for 90 consecutive days. Mice of all groups were observed for 15 weeks to record tumor incidence (fibrosarcoma) and survival time. After 15 weeks the mice were sacrificed for the estimation of hematological profiles like hemoglobin (Hb), white blood cell (WBC), red blood cell (RBC), and liver biochemical parameters, namely lipid peroxidation, reduced glutathione (GSH), glutathione-S-transferase (GST), superoxide dismutase (SOD), and catalase (CAT). HAIA treatment markedly reduced tumor incidence and prolonged the life span of sarcoma-bearing mice as compared to 20-MC control mice. Hematological profiles were significantly (p < 0.001) restored to normal levels in HAIA-treated mice as compared to 20-MC control mice. HAIA treatment significantly (p < 0.001) modulated the aforesaid liver biochemical parameters as compared to 20-MC control. The results concluded that I. aspalathoides demonstrated a remarkable chemopreventive effect in chemical-induced carcinogenesis in mouse. The potential chemopreventive action may be due to its antioxidant and detoxifying properties.     

Variation in secondary metabolite and aragonite concentrations in the tropical green seaweed Neomeris annulata: effects on herbivory by fishes

The tropical alga Neomeris annulata (Dickie) (Dasycladaceae: Chlorophyta) produces brominated sesquiterpenes and deposits aragonite throughout the thallus. This study, conducted throughout 1990–1991, showed that the fleshy, apical portions of the thalli (tips) were high in secondary metabolite concentrations (1.5%, mean combined secondary metabolites based on dry mass) and relatively low in calcium carbonate (aragonite form) (65.2% ash). The basal portions were lower in combined secondary metabolites (0.2% dry mass), and higher in aragonite (90.0% ash). The crude organic extract of the alga deterred fish feeding in the field at concentrations of 5, 10 and 15% dry mass, but not at a lower concentration of 1.5%. Natural concentrations of crude organic extract ranged from 1.5 to 15.3% in whole individuals and averaged 5.1% based on dry mass. Two brominated sesquiterpenes were isolated as major metabolites from the crude extract, but only one deterred feeding at natural concentrations. Ash concentrations in N. annulata were 60% dry mass in both the tips and bases. Aragonite strongly deterred feeding at concentrations of 65 and 90% dry mass. When a naturally occurring combination of organic extract and aragonite in the tips (10% crude extract and 65% aragonite) was compared with that of the bases (0.8% crude extract and 90% aragonite), no significant difference in grazing was observed. Combinations of secondary metabolites and aragonite were also tested against one or the other single defense. The combination of defenses proved a more effective deterrent than either secondary metabolites or aragonite alone.     

Protective role of Curcuma longa extract and curcumin on mercuric chloride-induced nephrotoxicity in rats: evidence by histological architecture

Mercury (Hg) is a potent nephrotoxin. The aim of this study was to investigate the protective role of Curcuma longa extract and curcumin against HgCl₂-induced nephrotoxicity. Male Sprague Dawley rats were administered HgCl₂ (12 μmol kg^?1, ip; once only) followed by treatment of Curcuma longa extract (200 mg kg^?1, po) and curcumin (80 mg kg^?1, po) for three days after 24 h of HgCl₂ administration. The present results showed that mercuric chloride administration caused an impairment of renal function system which was evident from significant increase in urea, creatinine, uric acid, and blood urea nitrogen concentration in serum. In addition, the swelling in glomerulus and degenerated renal tubules with obstructed lumen was also observed by acute mercuric chloride administration. Treatment with Curcuma longa extract and curcumin was effective in restoring all variables of kidney functions near to control group, which was consistent with kidney histoarchitecture. In conclusion, these results suggest that Curcuma longa extract and curcumin protect against HgCl₂-induced nephrotoxicity. This study could be important for the further understanding of mercury toxicity in renal tissues and in the development of better treatments for people and/or animals exposed to the metal.     

Potential hepatoprotective effects of vitamin E and Nigella sativa oil on hepatotoxicity induced by chronic exposure to malathion in human and male albino rats

Malathion is an organophosphorus (OP) insecticide and has a wide range of use in agriculture, veterinary medicine, and public health. Malathion and other OP insecticides produce hepatotoxic effects. The objective of the present study was to investigate the protective effects of Nigella sativa oil and α-tocopherol (vitamin E) on the hepatotoxicity induced by malathion on workers involved in the formulation of pesticides, chronically exposed to malathion, and in male albino rats orally administrated malathion. This study was conducted on both human and experimental animals, the human study was conducted on 30 control subjects working as administrators and 45 subjects working in formulation of pesticides and exposed to malathion (≥3 years), all were males with age ranges from 30 to 60 years. The 45 males working in pesticides formulation were classified into three groups; (1) 15 workers exposed to pesticides (2) 15 workers exposed to pesticides and received vitamin (E), in a dose of 10 mg kg?1 day^?1 orally for 60 days, and (3) 15 workers exposed to pesticides and received 100 mg kg^?1 day^?1 of N. sativa oil for 60 days. The animal experiment was conducted on 40 adult male albino rats weighing 150–200 g. They were divided into four groups (10 rats in each group). First group served as the control group, the second group received malathion in a dose of 50 mg kg^?1 orally per day for 60 days, the third group received malathion (in the same dose and route of administration) and vitamin E in a dose of 10 mg kg^?1 day^?1 orally for 60 days, and the fourth group received malathion (in the same dose and route of administration) and N. sativa oil in a dose of 100 mg kg^?1 day^?1 orally for 60 days. Liver function tests (alanine aminotransferase [ALT], aspartate aminotransferase [AST], serum alkaline phosphatase [ALP], albumin, globulin, albumin/globulin ratio, and total proteins), antioxidant enzymes (catalase (CAT), superoxide dismutase (SOD), and total glutathione peroxidase (GPx)), and lipid peroxidation [MDA] were analyzed in both human and animal experiments. The results of both human and animal study revealed that, exposure to malathion produced significant increases in AST, ALT, and lipid peroxidation. There were significant decrease in albumin, albumin/globulin ratio, total protein, and antioxidant enzymes. There was no significant change in ALP. In addition exposed workers showed significant decreases in serum globulin. Nigella sativa oil or vitamin E administration showed significant improvement of liver function tests, lipid peroxidation, and antioxidant enzymes impairment induced by malathion. Thus, dietary supplement, N. sativa oil, or vitamin E may represent a potential therapeutic agent in reducing malathion-induced hepatotoxicity.     

Oviposition site guarding by male walnut flies and its possible consequences for mating success

Field studies showed that male Rhagoletis juglandis and R. boycei flies guard egg-laying punctures (and the eggs within) on host walnut (Juglans major) fruit and defend those sites from conspecific and heterospecific males. In field experiments with artificially punctured fruit,as well as field observations on unmanipulated fruit, males were consistently more likely to be sighted and stayed longer on damaged fruit than on undamaged fruit. On artificially punctured fruit, they consistently spent more time in the vicinity of a puncture than expected by chance alone. Males together on damaged fruit were more likely to engage in contests over those fruit than males together on undamaged fruit. Copulations were consistently more frequent for either species on damaged than undamaged fruit, both in observations of unmanipulated fruit and in artificial puncture experiments. Analyses which controlled for the longer male residence time on damaged fruit suggested strongly that copulations were consistently achieved at higher per capita rates on damaged than on undamaged fruit, indicating that puncture-guarding functions to increase access to females. An exception to the pattern in male mating success was noted at a site where both species used host fruit on the same trees. In this case, R. juglandis males were only slightly more common on punctured fruit than on control fruit and male success in copulation did not differ significantly between the two types of fruit. This anomalous result was apparently due to an almost absolute advantage enjoyed by R. boycei males in on-fruit contests with R. juglandis males. A likely basis for improvements in mating success associated with puncture guarding was a propensity for females to deposit eggs into existing punctures. Both in observations of unmanipulated fruit and in artificial puncture experiments, females consistently attempted oviposition more often in damaged than undamaged fruit. In artificial puncture experiments, both species at both sites deposited most clutches in damaged fruit. Mating generally took place as females initiated oviposition. The possible functions of puncture use by females as well as alternative functions of puncture guarding by males are discussed.