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31.
AIM OF THE STUDY: This investigation evaluated the effect of a hydroethanolic extract of Baccharis trimera on pregnant Wistar rats, once the plant is well-known consumed in pregnancy and little is known on its potentially toxic effects on pregnant women. MATERIAL AND METHODS: Thirty-five female rats were distributed into three groups. Those in treatments 1 and 2 were given 8.4 mg/kg of the extract orally from gestational day (GD) 1 to 19 and from GD 6 to 15, respectively, whereas those in the control group received distilled water orally from GD 1 to 19. Body weights were recorded on GD 1, 6, 15, and 20. On GD 20 animals were anesthetized, blood samples were collected and maternal livers, kidneys, and spleens were weighed and processed for histological studies. RESULTS: No clinical signs of maternal toxicity and no changes in hematological parameters were observed. Urea levels and kidney weights differed significantly between animals receiving treatment 1 and controls. Histopathological alterations were found in kidneys and livers in both treatment groups. CONCLUSIONS: The hydroethanolic extract of Baccharis trimera administered to pregnant rats at 8.4 mg/kg was toxic to maternal kidney and liver cells, although such alterations are reversible once administration is discontinued.  相似文献   
32.
Anisomeles indica (L.) Kuntze (Labiatae), is a traditional anti-inflammatory herb used in Taiwan. The aqueous and methanolic extracts of whole plants, leaves, flowers and stems; and chloroform and n-butanol fractions of methanol extract, from A. indica were investigated for their anti-inflammatory activity on murine peritoneal macrophages. In addition, the tumor cells proliferation inhibition activities of these extracts were also evaluated against a panel of tumor cell lines such as Colon 205, PC 3, HepG2 and MCF 7. Treatment with A. indica extracts did not reduce cell viability at any dose used. However, all the extracts significantly inhibited the enhanced production of NO radicals, and pro-inflammatory cytokines (TNF-alpha, and IL-12) induced by LPS/IFN-gamma in a dose-dependent manner. Furthermore, methanolic extracts of leaves and flowers significantly and dose-dependently arrest mitogen-stimulated spleen cells in G0/G1 stage, in addition to their cell proliferation inhibition against Colon 205, MCF 7 and PC 3 by 94, 82; 98, 71; 82, 98%, respectively, at 200 microg/mL concentration. This is the first report on A. indica extracts for their growth inhibitory activities, against inflammatory mediator production, and human tumor cell lines, colon, prostate, hepatoma and breast cells proliferation.  相似文献   
33.
Kaempferia galanga Linn. (Zingiberaceae) presents many chemical constituents of the volatile oil extracted from the rhizome. The rhizome of Kaempferia galanga is used by people in many regions for relieving toothache, abdominal pain, muscular swelling and rheumatism. In this study we investigated the antinociceptive activity in mice and rats using acetic acid-induced writhing, formalin, hot plate and tail-flick tests. The extract at test doses of 50, 100 and 200 mg/kg, p.o. clearly demonstrated antinociceptive activity in all tests. This activity was dose- and time-dependent. The extract administered at 200 mg/kg, p.o. had a stronger antinociceptive effect than aspirin (100 mg/kg, p.o.) but less than morphine (5 mg/kg, s.c.). Naloxone (2 mg/kg, i.p.) abolished the antinociceptive action of both morphine (5 mg/kg, s.c.) and the extract (200 mg/kg, p.o.) in a similar manner. In conclusion, the methanol extract of Kaempferia galanga markedly demonstrated the antinociceptive action in experimental animals. The antinociceptive mechanisms appear to be both peripherally and centrally mediated actions and the opioid receptors are probably involved. Therefore, our studies support the use in traditional medicine of Kaempferia galanga against pain caused by various disorders.  相似文献   
34.
ETHNOPHARMACOLOGICAL RELEVANCE: Ginger rhizomes are used traditionally for management of different gastrointestinal disturbances. Several studies proved that the rhizome possesses diverse biological activities such as cytotoxic, antioxidant, and anti-inflammatory effects. Recently, interest in ginger for treatment of chronic inflammatory conditions has been renewed. AIM OF THE STUDY: The purpose of the present study is to evaluate the potential role of ginger extract [GE] in modulating the extent and severity of ulcerative colitis (UC), a chronically recurrent inflammatory bowel disease of unknown origin. MATERIALS AND METHODS: Male Wistar rats received 3 different doses of GE, sulfasalazine, or vehicle for 3 consecutive days before induction of UC by intra-rectal acetic acid administration, and continued further for 7 days after the induction. The colonic mucosal injury was assessed by macroscopic scoring, and histological examination. Furthermore, the mucosal content of malondialdehyde (MDA), protein carbonyl (PCO), and reduced glutathione (GSH) with the catalase (CAT) and superoxide dismutase (SOD) activity, were appraised as parameters of the redox state. Acute inflammatory response was determined by measuring myeloperoxidase (MPO), tumor necrosis factor (TNF-alpha), and prostaglandin E2 (PGE2). RESULTS: All parameters were altered in ulcerated rats, and improved in animals receiving GE, an effect that was comparable to that of the standard sulfasalazine, especially at the highest dose level. Colonic mucosal injury parallels with the histological and biochemical evaluations. CONCLUSIONS: Results showed a valuable effect of ginger extract against acetic acid-induced ulcerative colitis possibly by its antioxidant and anti-inflammatory properties.  相似文献   
35.
Extracts of Hypoxis hemerocallidea Fisch. & C. A. Mey. (Hypoxidaceae) corm (popularly known as 'African potato') are extensively used in South African traditional medicines for the treatment, management and/or control of an array of human ailments, including childhood convulsions and epilepsy. This study examined the anticonvulsant activity of the plant's corm aqueous extract (APE, 50-800 mg/kg i.p.) against pentylenetetrazole (PTZ)-, picrotoxin (PCT)- and bicuculline (BCL)-induced seizures in mice. Phenobarbitone and diazepam were used as reference anticonvulsant drugs for comparison. Like the reference antiseizure drugs used, Hypoxis hemerocallidea corm aqueous extract (APE, 100-800 mg/kg i.p.) significantly delayed (p < 0.05-0.001) the onset of, and antagonized, pentylenetetrazole (PTZ)-induced seizures. The plant's corm aqueous extract (APE, 100-800 mg/kg i.p.) also profoundly antagonized picrotoxin (PCT)-induced seizures, but only weakly antagonized bicuculline (BCL)-induced seizures. Although the data obtained in the present study do not provide conclusive evidence, it would appear that 'African potato' aqueous extract (APE) produces its antiseizure effect by enhancing GABAergic neurotransmission and/or action in the brain. The results of this laboratory animal study indicate that APE possesses anticonvulsant activity in the mammalian experimental model used and, therefore, tend to suggest that the herb may be used as a natural supplementary remedy in the management, control and/or treatment of childhood convulsions and epilepsy. In conclusion, the findings of this study indicate that Hypoxis hemerocallidea corm aqueous extract possesses anticonvulsant activity, and thus lend pharmacological credence to the suggested folkloric, anecdotal ethnomedical uses of the herb in the management of childhood convulsions and epilepsy in some rural communities of South Africa.  相似文献   
36.
Dietary interventions may have the potential to counter age-related cognitive decline. Studies have demonstrated an improvement in age-related cognitive impairment in animals after supplementation with plant extracts containing flavonoids but there are few human studies. This double-blind, controlled study examined the effects on cognitive performance of a 5 week supplementation with Enzogenol Pinus radiata bark extract containing flavonoids, in 42 males aged 50-65 years, with a body mass index >25. Participants were supplemented for 5 weeks either with Enzogenol plus vitamin C, or with vitamin C only. A battery of computerized cognitive tests was administered, and cardiovascular and haematological parameters were assessed prior to and following supplementation. The speed of response for the spatial working memory and immediate recognition tasks improved after supplementation with Enzogenol plus vitamin C, whereas vitamin C alone showed no improvements. A trend in a reduction of systolic blood pressure was observed with Enzogenol plus vitamin C, but not with vitamin C alone. The blood safety parameters were unchanged. The findings suggest a beneficial effect of supplementation with Enzogenol on cognition in older individuals. Larger studies are needed to ascertain its potential as a preventive treatment for age-related cognitive decline.  相似文献   
37.
Lipotoxicity is closely related to the etiology and complications of type 2 diabetes mellitus. This study investigated the protective effect of an extract from bamboo Phyllostachys edulis against palmitic acid (PA)-induced lipoapoptosis. The lipo-detoxification function of the bamboo extract (BEX) was evaluated using cell culture models. Cell viability was measured by MTT assay and cell apoptosis was monitored by Annexin V staining. Cellular uptake of fluorescent free fatty acid (FFA) analog was measured by flow cytometry. Protein levels of total protein kinase B (Akt) and phosphorylated Akt (p-Akt) were measured by western blotting. The results show that co-incubating BEX with mouse myoblast C2C12 cells had no effect on the cellular uptake of FFA, but dramatically decreased PA-induced cell apoptosis and protected cell viability. A similar antilipotoxicity effect of BEX was observed in other mammalian cells. BEX significantly decreased the protein levels of both Akt and p-Akt in C2C12 cells under normal cell culture conditions but not under lipotoxic conditions, indicating the regulatory effect of BEX on cell signaling pathways and its response to a high FFA environment. This study demonstrated a novel function of bamboo extract in preventing lipotoxicity in mammalian cells, implicating a promising phytotherapeutic approach for lipo-detoxification.  相似文献   
38.
The increase in solar ultraviolet radiation (UVR) that reaches the Earth’s surface should make us reflect on the need to develop new approaches in protecting the skin from UVR exposure. The present study aims to evaluate the photoprotective and antiaging efficacy of a red orange extract (100 mg/day) in both Asian and Caucasian subjects. A randomized, double-blind, controlled study was carried out in 110 Asian and Caucasian subjects. Product efficacy was measured as follows: (1) the photoprotective effect was measured by the minimal erythema dose (MED) assessment; (2) the efficacy in decreasing the UVA+B-induced skin redness was measured by colorimetry; (3) the antioxidant efficacy was measured by the ferric-reducing antioxidant power (FRAP) and the malondialdehyde (MDA) assay; and (4) skin moisturization, skin elasticity, skin radiance, the intensity of melanin staining, transepidermal water loss (TEWL), and wrinkles were measured to assess the antiaging efficacy. The intake of the product for 56 days was effective in improving the skin reaction to UV exposure; in increasing the skin antioxidant capacity as well as in decreasing UVA-induced lipid peroxidation; in increasing the skin moisturization, skin elasticity, and skin radiance; and in decreasing TEWL, the intensity of melanin staining inside dark spots, and wrinkle depth. Our results suggest that the test product is effective in counteracting both the harmful effects of UVR exposure and aging signs.  相似文献   
39.
目的研究速殖子超声裂解物(TSo)和IFN-γ鼻内免疫小鼠经口感染弓形虫速殖子后,血清、小肠液和粪便IgA抗体分泌的动态变化。方法将6~7周龄BALB/c小鼠100只随机分为4组,每组25只,分别用10μl缓冲液PBS、20μgTSo、500UIFN-γ和20μgTSo 500UIFN-γ鼻内免疫小鼠。用RH株弓形虫速殖子4×104个/只灌胃攻击,分别于攻击后第7、10、13、16、19天处死小鼠,收集血清、小肠液及粪便,ELISA法测定IgA含量。结果各组血清IgA抗体水平在攻击后第10天达到峰值,TSo IFN-γ组血清IgA抗体含量高于其他各组。小肠液和粪便IgA抗体含量在攻击后第13天达到峰值,在实验期各时点TSo IFN-γ组小肠液和粪便IgA抗体含量高于其他组。小肠液与粪便IgA抗体水平呈正相关。结论TSo或IFN-γ或TSo联合IFN-γ鼻内免疫小鼠可诱导黏膜免疫,产生高水平的弓形虫特异性IgA抗体。TSo联合IFN-γ鼻内免疫优于单独免疫,免疫小鼠肠道产生大量SIgA,发挥抗虫作用。鼻黏膜免疫是一种安全有效的免疫接种途径。  相似文献   
40.
本文用 BALB/3T3 A31-1-13细胞系研究了煤尘抽提物的转化活性。亚硝化和未亚硝化的煤尘抽提物都能诱发细胞发生转化且有剂量反应关系.但亚硝化煤尘抽提物的转化活性比未亚硝化者高。从转化集落分离出来的细胞具有赘生转化的一些特征,如细胞生长迅速、接触抑制消失和停泊不依赖性生长等.本文结果看来支持煤矿工胃癌高发原因的煤尘假说。  相似文献   
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