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1.

Background

Artocarpus communis is used traditionally in Cameroon to treat several ailments, including infectious and associated diseases. This work was therefore designed to investigate the antimicrobial activities of the methanol extract (ACB) and compounds isolated from the bark of this plant, namely peruvianursenyl acetate C (1), α-amyrenol or viminalol (2), artonin E (4) and 2-[(3,5-dihydroxy)-(Z)-4-(3-methylbut-1-enyl)phenyl]benzofuran-6-ol (5).

Methods

The liquid microdilution assay was used in the determination of the minimal inhibitory concentration (MIC) and the minimal microbicidal concentration (MMC), against seven bacterial and one fungal species.

Results

The MIC results indicated that ACB as well as compounds 4 and 5 were able to prevent the growth of all tested microbial species. All other compounds showed selective activities. The lowest MIC value of 64 μg/ml for the crude extract was recorded on Staphylococcus aureus ATCC 25922 and Escherichia coli ATCC 8739. The corresponding value of 32 μg/ml was recorded with compounds 4 and 5 on Pseudomonas aeruginosa PA01 and compound 5 on E. coli ATCC 8739, their inhibition effect on P. aeruginosa PA01 being more than that of chloramphenicol used as reference antibiotic.

Conclusion

The overall results of this study provided supportive data for the use of A. communis as well as some of its constituents for the treatment of infections associated with the studied microorganisms.  相似文献   

2.

Purpose

There is wide variability of the location of the superior thyroid artery (STA). Our purpose was to describe variations of the STA origin, with great respect to different anatomical patterns which could be observed in humans.

Methods

The material was 68 formalin-embalmed adult cadavers of both sexes (45–70-year-old). Methodologically, we dissected the neck region bilaterally and focused on studying the external carotid artery (ECA) branches, especially the STA emerging pattern. We also measured the distance of the STA origin from the common carotid artery (CCA) bifurcation (using the latter as a landmark).

Results

Based on our results we categorized the STA emerging pattern into three major types A, B and C according to its origin (which was CCA, ECA and CCA bifurcation, respectively). Regarding type B, we found that the left STA arises approximately 2 mm closer to the CCA bifurcation compared to the right STA (p < 0.05).

Conclusions

The STA is a carotid branch with variable origin, which can be CCA, ECA or CCA bifurcation. It is also an artery of great clinical importance in head and neck surgery. The present study provided data of the STA emerging patterns, as well as a review of its clinical anatomy.  相似文献   

3.

Background

Plants play a significant role in maintaining human health and improving the quality of human life. They serve humans well as valuable components of food, as well as in cosmetics, dyes, and medicines. In fact, many plant extracts prepared from plants have been shown to exert biological activity in vitro and in vivo. The present study explored antioxidant and antigenotoxic effects of Daphne gnidium leaf extracts.

Methods

The genotoxic potential of petroleum ether, chloroform, ethyl acetate, methanol and total oligomer flavonoid (TOF) enriched extracts from leaves of Daphne gnidium, was assessed using Escherichia coli PQ37. Likewise, the antigenotoxicity of the same extracts was tested using the ??SOS chromotest test??. Antioxidant activities were studied using non enzymatic and enzymatic method: NBT/Riboflavine and xantine oxidase.

Results

None of the different extracts produced a genotoxic effect, except TOF extract at the lowest tested dose. Our results showed that D. gnidium leaf extracts possess an antigenotoxic effect against the nitrofurantoin a mutagen of reference. Ethyl acetate and TOF extracts were the most effective in inhibiting xanthine oxidase activity. While, methanol extract was the most potent superoxide scavenger when tested with the NBT/Riboflavine assay.

Conclusions

The present study has demonstrated that D. gnidium leaf extract possess antioxidant and antigenotoxic effects. These activities could be ascribed to compounds like polyphenols and flavonoid. Further studies are required to isolate the active molecules.  相似文献   

4.

Background

Although the use of bortezomib alone and in combination with steroids has shown efficacy in AL amyloidosis, its role in combination with high-dose melphalan and autologous stem cell transplantation (HDM/SCT) is unknown. In this study, we evaluated bortezomib in combination with dexamethasone (BD) for induction chemotherapy prior to HDM/SCT.

Methods

This was a single-center, prospective, randomized controlled trial comparing induction therapy consisting of two BD cycles followed by HDM/SCT (BD?+?HDM/SCT) with HDM/SCT alone in the treatment of patients with newly diagnosed AL amyloidosis. The hematological and organ responses of the patients were assessed every three months post HDM/SCT.

Results

Fifty-six patients newly diagnosed with renal (100%), cardiac (57.1%), liver (7.1%), or nervous system (8.9%) AL amyloidosis were enrolled in this study; 28 patients were assigned to each arm. Two patients died within 100 days of HDM/SCT (3.6% treatment-related mortality). The overall hematologic response rates in the BD?+?HDM/SCT arm and HDM/SCT arm at three, six and twelve months were 78.5% versus 50%, 82.1% versus 53.5% and 85.7% versus 53.5%, respectively. In the BD?+?HDM/SCT arm, 15 (53.5%) patients achieved a hematologic response after BD and before HDM/SCT. An intention-to-treat analysis revealed a higher rate of complete remission in the BD?+?HDM/SCT arm at both 12 and 24 months (67.9% and 70%, respectively) than with the HDM/SCT-only therapy (35.7% and 35%, respectively, P?=?0.03). After a median follow-up of 28 months, the survival rates at 24 months post-treatment start were 95.0% in the BD?+?HDM/SCT group and 69.4% in the HDM/SCT alone group (P?=?0.03).

Conclusions

Our preliminary data suggest that the outcome of treating AL amyloidosis with BD induction and HDM/SCT was superior to the outcome of the HDM/SCT treatment alone.

Trial registration

This trial has been registered at clinicaltrials.gov with the number NCT01998503.  相似文献   

5.

Objective

Marine algae are abundant sources of sulfated polysaccharides with various biological activities. Consequently, their biomolecules are of great of commercial interest. In this study, we investigated the potential antinociceptive activity of a sulfated polysaccharide obtained from the green seaweed Caulerpa racemosa (CrII) and the involvement of the hemoxigenase-1 (HO-1) pathway in its anti-inflammatory effect.

Methods

We used a systemic evaluation to verify possible toxic effects of Crll after consecutive treatments. Swiss mice and Wistar rats were used for all experiments.

Results

In Swiss mice, CrII (0.01, 0.1 and 1.0 mg/kg) significantly reduced the number of abdominal contortions and the duration of paw licking in the second phase after treatment with acetic acid and formalin, respectively. However, CrII was unable to prolong the reaction time of thermally stimulated animals. The anti-inflammatory effect of CrII (0.01, 0.1 and 1.0 mg/kg) was evidenced by a decreased number of leukocytes in the peritoneal cavities of the rats. CrII (0.01, 0.1 and 1.0 mg/kg) also reduced the amount of paw edema induced by carrageenan (Cg) and dextran. The anti-inflammatory effect of CrII was confirmed by reduced levels of myeloperoxidase in the paw tissue of the Cg groups. After inhibition with ZnPP IX, a specific HO-1 phenotype inhibitor, the anti-inflammatory effect of CrII was no longer observed in Cg-induced paw edema tests. Consecutive Crll (1.0 mg/kg) for 14 days did not change any biochemical or histopathological parameters, or cause mortality of mice.

Conclusions

CrII did not produce any signs of toxicity and effectively decreased nociception and inflammation. Also, the anti-inflammatory effect of Crll is at least in part dependent on the integrity of the HO-1 pathway.  相似文献   

6.

Background

Functional magnetic resonance imaging (fMRI) analysis is commonly done with cross-correlation analysis (CCA) and the General Linear Model (GLM). Both CCA and GLM techniques, however, typically perform calculations on a per-voxel basis and do not consider relationships neighboring voxels may have. Clustered voxel analyses have then been developed to improve fMRI signal detections by taking advantages of relationships of neighboring voxels. Mean-shift clustering (MSC) is another technique which takes into account properties of neighboring voxels and can be considered for enhancing fMRI activation detection.

Methods

This study examines the adoption of MSC to fMRI analysis. MSC was applied to a Statistical Parameter Image generated with the CCA technique on both simulated and real fMRI data. The MSC technique was then compared with CCA and CCA plus cluster analysis. A range of kernel sizes were used to examine how the technique behaves.

Results

Receiver Operating Characteristic curves shows an improvement over CCA and Cluster analysis. False positive rates are lower with the proposed technique. MSC allows the use of a low intensity threshold and also does not require the use of a cluster size threshold, which improves detection of weak activations and highly focused activations.

Conclusion

The proposed technique shows improved activation detection for both simulated and real Blood Oxygen Level Dependent fMRI data. More detailed studies are required to further develop the proposed technique.  相似文献   

7.

Objective

It has been reported that the intravenous anesthetic propofol (PPF) has anti-inflammatory effects in vitro and in patients. The purpose of this study was to investigate whether PPF has anti-inflammatory effects in lipopolysaccharide (LPS)-induced septic shock by inhibiting the induction of pro-inflammatory cytokines [interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α)] and high mobility group box 1 (HMGB1) in rats.

Methods

Thirty six male Wistar rats were randomly assigned to one of three groups (control group, PPF + LPS group and LPS group; n = 12 per group). Control group rats received a 0.9% NaCl solution (NS) by the tail vein. The PPF + LPS group rats received PPF (10 mg/kg bolus, followed by infusion at 10 mg/(kg·h) through a femoral vein catheter) 1 h before LPS (7.5 mg/kg) administration via the tail vein. The LPS group rats received injection of LPS (7.5 mg/kg) via the tail vein. Hemodynamic effects were recorded as well as mortality rates, and plasma cytokine con-centrations (TNF-α, IL-6, HMGB1) were measured for the 24-h observation period.

Results

The mean arterial pressure and heart rate of the PPF + LPS group were more stable than those of the LPS group. The mortality at 24 h after the administration of the LPS injection was much higher in the LPS group (58.3%) compared to the PPF + LPS group (25.0%). Plasma concentrations of cytokines (IL-6 and TNF-α) and HMGB1 were significantly reduced in the PPF + LPS group compared to the LPS group (P < 0.05).

Conclusion

Pretreatment with PPF reduced the mortality rate of rats and attenuated the pro-inflammatory cytokine responses in an endotoxin shock model through an anti-inflammatory action inhibiting induction of HMGB1.  相似文献   

8.

Background

The skin is chronically exposed to endogenous and environmental pro-oxidant agents, leading to the harmful generation of reactive oxygen species. Antioxidant is vital substances which possess the ability to protect the body from damage cause by free radicals induce oxidative stress. Alpinia zerumbet, a traditionally important economic plant in Okinawa, contains several interesting bioactive constituents and possesses health promoting properties. In this regard, we carried out to test the inhibitory effect of crude extracts and isolated compounds from A. zerumbet on antioxidant and skin diseases-related enzymes.

Methods

The antioxidant activities were examined by DPPH, ABTS and PMS-NADH radical scavenging. Collagenase, elastase, hyaluronidase and tyrosinase were designed for enzymatic activities to investigate the inhibitory properties of test samples using a continuous spectrophotometric assay. The inhibitory capacity of test samples was presented at half maximal inhibitory concentration (IC50).

Results

The results showed that aqueous extract of the rhizome was found to have greater inhibitory effects than the others on both of antioxidant and skin diseases-related enzymes. Furthermore, 5,6-dehydrokawain (DK), dihydro-5,6-dehydrokawain (DDK) and 8(17),12-labdadiene-15,16-dial (labdadiene), isolated from rhizome, were tested for antioxidant and enzyme inhibitions. We found that DK showed higher inhibitory activities on DPPH, ABTS and PMS-NADH scavenging (IC50?=?122.14?±?1.40, 110.08?±?3.34 and 127.78?±?4.75???g/ml, respectively). It also had stronger inhibitory activities against collagenase, elastase, hyaluronidase and tyrosinase (IC50?=?24.93?±?0.97, 19.41?±?0.61, 19.48?±?0.24 and 76.67?±?0.50???g/ml, respectively) than DDK and labdadiene.

Conclusion

Our results indicate that the rhizome aqueous extract proved to be the source of bioactive compounds against enzymes responsible for causing skin diseases. Moreover, DK could be used as a potent inhibitor and be further exploited to be used in anti-skin disease formulations.  相似文献   

9.

Background

Light chain amyloidosis (AL) is a rare plasma cell dyscrasia associated with poor survival especially in the setting of heart failure. Late gadolinium enhancement (LGE) on cardiac MRI was recently found to correlate with myocardial amyloid deposition but the prognostic role is not established. The aim is to determine the prognostic significance of LGE in AL by comparing long term survival of AL patients with and without LGE.

Methods

Twenty nine consecutive patients (14 females; 62 ± 11 years) with biopsy-proven AL undergoing cardiac MRI with gadolinium as part of AL workup were included. Survival was prospectively followed 29 months (median) following MRI and compared between those with and without LGE by Kaplan-Meier and log-rank analyses.

Results

LGE was positive in 23 subjects (79%) and negative in 6 (21%). Left ventricular ejection fraction was 66 ± 17% in LGE-positive and 69 ± 12% in LGE-negative patients (p = 0.8). Overall 1-year mortality was 36%. On follow-up, 14/23 LGE-positive and none of LGE-negative patients died (log rank p = 0.0061). Presenting New York Heart Association heart failure class was also associated with poor survival (p = 0.0059). Survival between two LGE groups stratified by heart failure class still showed a significant difference by a stratified log-rank test (p = 0.04).

Conclusion

Late gadolinium enhancement is common and is associated with poor long-term survival in light chain amyloidosis, even after adjustment for heart failure class presentation. The prognostic significance of late gadolinium enhancement in this disease may be useful in patient risk-stratification.  相似文献   

10.

Objective

This study was conducted to evaluate the effect of p-Coumaric acid, a common dietary phenol, on monosodium urate crystal-induced inflammation in rats—an experimental model for acute gouty arthritis.

Methods

Paw edema, levels/activities of lysosomal enzymes, lipid peroxidation, enzymic antioxidants and a histopathological examination of ankle joints were evaluated in control and monosodium urate crystal-induced inflamed rats. Further, an acetic acid-induced writhing test and tail immersion test were employed to screen for analgesic effects, yeast-induced pyrexia was used to test for antipyretic effects, and gastric ulceration was used to evaluate ulcerogenic effects.

Results

A significant increase in paw edema, lysosomal enzyme activity and lipid peroxidation levels was observed in monosodium urate crystal-induced rats, whereas activities of enzymic antioxidants were found to be decreased when compared to control rats. Nevertheless, treatment with p-Coumaric acid (100 mg/kg b.wt) significantly reverted the altered physical and biochemical parameters back to near normal levels, as evidenced by the histopathology of the ankle joints. In addition, p-Coumaric acid also exhibited potent analgesic and antipyretic effects devoid of any adverse impact on gastric mucosa.

Conclusion

The results of this study reveal the potential anti-inflammatory effect of p-Coumaric acid against monosodium urate crystal-induced inflammation in rats.  相似文献   

11.

Background

Platinum-based combinations are the standard second-line treatment for platinum-sensitive ovarian cancer (OC). This randomized phase II study was undertaken in order to compare the combination of carboplatin and pegylated liposomal doxorubicin (LD) with carboplatin and paclitaxel (CP) in this setting.

Methods

Patients with histologically confirmed recurrent OC, at the time of or more than 6 months after platinum-based chemotherapy, were randomized to six cycles of CP (carboplatin AUC5 + paclitaxel 175 mg/m2, d1q21) or CLD (carboplatin AUC5 + pegylated LD 45 mg/m2, d1q28).

Results

A total of 189 eligible patients (CP 96, CLD 93), with a median age of 63 years, median Performance Status (PS) 0 and a median platinum free interval (PFI) of 16.5 months, entered the study. Discontinuation due to toxicity was higher in the CP patients (13.5% versus 3%, P = 0.016). The overall response rate was similar: CP 58% versus CLD 51%, P = 0.309 (Complete Response; CR 34% versus 23%) and there was no statistical difference in time-to-progression (TTP) or overall survival (OS; TTP 10.8 months CP versus 11.8 CLD, P = 0.904; OS 29.4 months CP versus 24.7 CLD, P = 0.454). No toxic deaths were recorded. Neutropenia was the most commonly seen severe toxicity (CP 30% versus CLD 35%). More frequent in CLD were severe thrombocytopenia (11% versus 2%, P = 0.016), skin toxicity and Palmar-plantar erythrodysesthesia (PPE) grade 1-2 (38% versus 9%, P< 0.001), while grade 3 neurotoxicity and alopecia were higher in CP (7% versus 0%, P = 0.029, 20% versus 5%, P = 0.003). PS and PFI were independent prognostic factors for TTP and OS.

Conclusions

The combination of pegylated LD with carboplatin is effective, showing less neurotoxicity and alopecia than paclitaxel-carboplatin. It thus warrants a further phase III evaluation as an alternative treatment option for platinum-sensitive OC patients.

Trial Registration

Australian New Zealand Clinical Trials Registry: ACTRN12609000436279  相似文献   

12.

Background

Systemic lupus erythematosus (SLE), a multisystemic disease of young women may be disfiguring and affect physical and emotional health. Body image literature in SLE is scant and controversial.

Purpose

We compared body image-related quality of life in subjects with (n?=?87) and without (n?=?78) SLE and determined its correlates using the body image quality of life inventory (BIQLI).

Method

The tool was self-administered to consenting individuals. Demographic information along with disease activity and damage assessments for SLE patients were obtained. T test, chi square test, correlational, and regression analyses were used to make comparisons.

Results

Mean age (±SD) were 42.4?±?13.1 and 38.7?±?13.2?years for SLE and non-SLE subjects, respectively. Mean (±SD) BIQLI scores were significantly worse in SLE than non-SLE subjects: 19.9?±?33.2 and 41.6?±?24.8 (p?=?0.001). In SLE, BIQLI scores correlated inversely with overall damage, irreversible cutaneous damage, alopecia, and self-reported depression, and directly with age and health status.

Conclusion

Body image in SLE is poor, and effective interventions may be directed at cutaneous disease activity, damage, and depression.  相似文献   

13.
14.

Introduction

We reassessed the histopathology and origin of amyloid in liver biopsies.

Materials and Methods

All liver biopsies were retrieved from a series of 588 cases with histologically confirmed amyloidosis submitted between February 2006 and January 2009 to the Amyloid Registry of the Charité University Hospital. Liver biopsies had been fixed in formalin and embedded in paraffin. 3-5 μm thick paraffin sections were stained with hematoxylin and eosin and Congo red. Amyloid was classified immunohistochemically, using antibodies directed against amyloid P-component, AA amyloid, apolipoprotein AI, fibrinogen, lysozyme, λ- and κ-light chain, and transthyretin.

Results

Amyloid was found in 46 liver biopsies (29 men, 17 women; mean age 60 years, range 34-87 years). Immunohistochemical classification succeeded in 42 cases. AL amyloidosis was present in 40 (87%) cases and was further categorized into AL amyloid of λ-light chain origin in 26 (57%) cases, and κ-light chain origin in 14 (30%) cases. ATTR and AA amyloidosis were found in a single patient each (2%). In 4 (9%) cases, amyloid remained unclassified.

Conclusions

Hepatic amyloidosis is most commonly AL amyloid of λ- and κ-light chain origin and is often associated with marked parenchymal atrophy.  相似文献   

15.

Background

Chemicals of herbal products may cause unexpected toxicity or adverse effect by the potential for alteration of the activity of CYP450 when co-administered with other drugs. Eleutherococcus senticosus (ES), has been widely used as a traditional herbal medicine and popular herbal dietary supplements, and often co-administered with many other drugs. The main bioactive constituents of ES were considered to be eleutherosides including eleutheroside B (EB) and eleutheroside E (EE). This study was to investigate the effects of EB and EE on CYP2C9, CYP2D6, CYP2E1 and CYP3A4 in rat liver microsomes in vitro.

Method

Probe drugs of tolbutamide (TB), dextromethorphan (DM), chlorzoxazone (CLZ) and testosterone (TS) as well as eleutherosides of different concentrations were added to incubation systems of rat liver microsomes in vitro. After incubation, validated HPLC methods were used to quantify relevant metabolites.

Results

The results suggested that EB and EE exhibited weak inhibition against the activity of CYP2C9 and CYP2E1, but no effects on CYP2D6 and CYP3A4 activity. The IC50 values for EB and EE were calculated to be 193.20 μM and 188.36 μM for CYP2E1, 595.66 μM and 261.82 μM for CYP2C9, respectively. Kinetic analysis showed that inhibitions of CYP2E1 by EB and EE were best fit to mixed-type with Ki value of 183.95 μM and 171.63 μM, respectively.

Conclusions

These results indicate that EB and EE may inhibit the metabolism of drugs metabolized via CYP2C9 and CYP2E1, and have the potential to increase the toxicity of the drugs.  相似文献   

16.

Background

Ribosome-inactivating proteins (RIP) have been studied in the search for toxins that could be used as immunotoxins for cancer treatment. Pulchellin, a type 2 RIP, is suggested to induce immune responses that have a role in controlling cancer.

Methods

The percentage of dendritic cells and CD4+ and CD8+ T cells in the spleen (flow cytometry), cytokines?? release by PECs and splenocytes (ELISA) and nitric oxide production by PECs (Griess assay) were determined from tumor-bearing mice injected intratumorally with 0.1?ml of pulchellin at 0.75???g/kg of body weight. Statistical analysis was performed by one-way ANOVA with Tukey??s post hoc test.

Results

Pulchellin-treated mice showed significant immune system activation, characterized by increased release of IFN-?? and Th2 cytokines (IL-4 and IL-10), while IL-6 and TGF-?? levels were decreased. There was also an increase in macrophage??s activation, as denoted by the higher percentage of macrophages expressing adhesion and costimulatory molecules (CD54 and CD80, respectively).

Conclusions

Our results suggest that pulchellin is promising as an adjuvant in breast cancer treatment.  相似文献   

17.

Objective

To test the inflammation and oxidative stress hypothesis in antiphospholipid syndrome (APS) patients and to identify possible associations with clinical and laboratory features of the disease.

Methods

Serum amyloid A (SAA), C-reactive protein (CRP), 8-isoprostane and prostaglandin E2 (PGE) were assayed in the sera of 45 APS patients and then compared to control groups made up of 15 antiphospholipid antibody (aPL) negative patients with systemic lupus erythematosus, 15 aPL negative subjects with pregnancy-related morbidity, 15 aPL negative patients with thrombosis, 15 subjects with persistently positive aPL with no signs or symptoms of APS, and 15 healthy volunteers from among the hospital staff.

Results

APS patients showed significantly higher CRP (p?=?0.01), SAA (p?p?=?0.05) and PGE2 (p?=?0.001) plasma levels as compared to controls. Among APS subjects, significantly higher 8-isoprostane and PGE2 levels were observed in patients with triple positivity for aPL (lupus anticoagulant, anticardiolipin and anti-beta2-glycoprotein I antibodies) compared to APS patients with single or double aPL positivity.

Conclusion

Both inflammation and oxidative stress, as measured by SAA, CRP, 8-isoprostane and PGE2, occur in APS and seem to be related to triple positivity for aPL.  相似文献   

18.

Background

The Drug Use Disorders Identification Test (DUDIT) was developed for problematic substance use screening, and for a more detailed assessment of problematic use, the Drug Use Disorders Identification Test-Extended (DUDIT-E) was additionally developed.

Purpose

Examining the psychometric properties of DUDIT and DUIT-E across diverse settings in populations of young drug users.

Methods

We examined the psychometric characteristics of these instruments across various settings in populations of young substance users differing in substance use severity and treatment status. Data were collected from three clinically relevant groups (n?=?259) as well as a control sample of college students (n?=?109).

Results

Reliability analyses indicated good internal consistency for both instruments; high intraclass correlations further indicated good test–retest reliability. Differences among study groups were significant on the DUDIT scale and all DUDIT-E subscales (p?<?0.01), with the target groups exhibiting higher scores compared to controls. A two-factor solution was identified for the factor structure of DUDIT.

Conclusion

The Hungarian version of DUDIT and DUDIT-E can effectively identify substance use problems among young users.  相似文献   

19.

Background

Nuna Kadugu (NK), a Siddha medicine prepared from leaves and fruits of Morinda Pubescens, used for the treatment of various skin diseases. Though NK has been widely used for several decades, no scientific report was available on its safety. Present study was undertaken to demonstrate the oral toxicity of NK in Sprague Dawley rats.

Methods

Acute and 28-day repeated oral toxicity studies were performed following OECD test guidelines 423 and 407, respectively, with minor modifications. In acute oral toxicity study, NK was administered at 2000mg/kg b.wt., p.o and animals were observed for toxic signs at 0, 0.5, 1, 4, 24 h and for next 14 days. Gross pathology was performed at the end of the study. In repeated dose, the 28- day oral toxicity study, NK was administered at 300, 600 and 900 mg/kg b.wt./p.o/day. Two satellite groups (control and high dose) were also maintained to determine the delayed onset toxicity of NK. Animals were observed for mortality, morbidity, body weight changes, feed and water intake. Haematology, clinical biochemistry, electrolytes, gross pathology, relative organ weight and histopathological examination were performed.

Results

In acute toxicity study, no treatment related death or toxic signs were observed with NK administration. In the repeated dose study, no significant differences in body weight changes, food / water intake, haematology, clinical biochemistry and electrolytes content were observed between control and NK groups. No gross pathological findings and difference in relative organ weights were observed between control and NK treated rats. Histopathological examination revealed no abnormalities with NK treatment.

Conclusion

Acute study reveals that the LD50 of NK is greater than 2000mg/kg, b.wt. in fasted female rats and can be classified as Category 5. 28-day repeated oral toxicity demonstrates that the No Observed Adverse Effect Level of NK is greater than 900 mg/kg b.wt./day, p.o in rats. There were no delayed effects in NK satellite group. In conclusion, NK was found to be non-toxic in the tested doses and experimental conditions.  相似文献   

20.

Background

Since oxidative stress has been implicated in a neurodegenerative disease such as Alzheimer's disease (AD), natural antioxidants are promising candidates of chemopreventive agents. This study examines antioxidant and neuronal cell protective effects of various fractions of the methanolic extract of Erigeron annuus leaf and identifies active compounds of the extract.

Methods

Antioxidant activities of the fractions from Erigeron annuus leaf were examined with [2,2-azino-bis(3-ethylbenz thiazoline-6-sulfonic acid diammonium salt)] (ABTS) and ferric reducing antioxidant power (FRAP) assays. Neuroprotective effect of caffeic acid under oxidative stress induced by H2O2 was investigated with [3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide] (MTT) and lactate dehydrogenase (LDH) assays.

Results

This study demonstrated that butanol fraction had the highest antioxidant activity among all solvent fractions from methanolic extract E. annuus leaf. Butanol fraction had the highest total phenolic contents (396.49 mg of GAE/g). Caffeic acid, an isolated active compound from butanol fraction, showed dose-dependent in vitro antioxidant activity. Moreover, neuronal cell protection against oxidative stress induced cytotoxicity was also demonstrated.

Conclusion

Erigeron annuus leaf extracts containing caffeic acid as an active compound have antioxidative and neuroprotective effects on neuronal cells.  相似文献   

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