黄顶菊对小麦根尖细胞的遗传毒性

为了探讨入侵植物黄顶菊的遗传毒性,以5个小麦品种为材料,研究5种不同浓度的黄顶菊浸提液对小麦根尖细胞有丝分裂的影响。结果表明,黄顶菊浸提液对小麦有明显的遗传毒性。浸提液抑制了小麦根尖细胞有丝分裂指数,使间期细胞出现微核、多核,使分裂期细胞出现染色体断片、染色体桥、多极分裂、染色体粘连等畸变现象。随着浸提液浓度增加,小麦根尖细胞有丝分裂指数下降,微核率和染色体畸变率升高。     

火炬树叶浸提液对小麦根尖细胞的遗传毒性

为了解入侵植物火炬树对小麦根尖细胞的遗传毒性,用不同浓度的火炬树叶浸提液(0.5‰、1‰、2‰、5‰、1%、3%、5%、7%、10%)处理萌发期的小麦根尖6、12、24和36h,观察其有丝分裂的变化和染色体行为的异常。结果表明,除低浓度(<2‰)浸提液外,火炬树叶浸提液对小麦根尖细胞产生了明显的毒害作用。随着处理浓度的升高和处理时间的延长,有丝分裂指数逐渐降低,同时诱发了微核、多核和染色体畸变的出现,畸变率随处理浓度的提高和处理时间的延长而逐渐升高。     

NaCl胁迫对玉米根尖细胞染色体行为的影响

用不同浓度的NaCl处理萌发的玉米种子。结果表明,随着NaCl浓度的升高,玉米根尖细胞有丝分裂指数降低,NaCl浓度高于100 mmol/L时,引起根尖细胞染色体行为异常,异常类型有微核、多核、染色体落后、染色体粘连、染色体桥、染色体断裂等,以多核和染色体粘连为主。染色体异常行为与NaCl处理浓度呈正相关。     

The Antioxidant and Anti-proliferative Activity of the Lebanese <Emphasis Type="Italic">Olea europaea</Emphasis> Extract

It is becoming increasingly evident that certain phytochemicals possess cancer chemopreventive properties. In this study, the anti-proliferative activity of plant extracts from olive (Olea europaea L.) leaves was tested on human leukemic cell line (Jurkat). Cytotoxicity of various concentrations of plant extracts was examined and the IC₅₀ was determined. Olive leaf extracts showed concentration-dependent anti-proliferative effect as determined by the WST-1 proliferation kit and [³H]-thymidine incorporation method. To study whether cell death was due to apoptosis, cells were stained with Annexin V-FITC and PI and the expression of important regulatory proteins (Bcl-2, Bax, and p53) involved in apoptosis were examined by Western blot. The antioxidant activity of olive leaves (SC₅₀ = 0.1 mg dry weight) was studied using the DPPH scavenging method. Present findings suggest that olive leaves extracts exhibit anti-proliferative effect on leukemic cells by inducing apoptosis.     

继代培养中离体甜菜的倍性变化与增殖

用卡宝品红法检测了不同来源离休甜菜的不同器官在不同年度间细胞焙性的变化。并统计分析了年度间变化的差异显著性及不同倍性优势细胞比率与增殖能力之间的相关性，结果表明，甜菜离休植株茎尖细胞倍性在继代培养中相对稳定，而根尖细胞倍性在年度间有显著变化。由未授粉胚珠培养再生的胚性细胞团，其细胞染色体容易自然加倍；再生的单倍体植株，其茎尖细胞为单倍体，而根尖细胞为二倍体。在所测年度内，离体甜菜细胞倍性的变化对其增殖能力无明显影响。通过茎尖和不断选择培养是离休甜菜保持遗传稳定性的有效手段。     

秋水仙素处理对黑麦根尖细胞有丝分裂的影响

为了解秋水仙素对黑麦根尖细胞有丝分裂的影响，以黑麦根尖为材料，在不同浓度秋水仙素（0．01％、0．05％、0．10％、0．15％、0．20％）和不同处理时间（12、24、36、48、60、72h）条件下测定了根尖细胞中期分裂指数和细胞加倍指数。结果表明，随着秋水仙素浓度的升高，细胞加倍指数增加，当秋水仙素浓度为0．15％时细胞加倍指数达到最大值（0．0362％），以后迅速下降。随着处理时间的延长，中期分裂指数逐渐下降，而细胞加倍指数在处理36h时达到最大值（0．0208％）。在浓度与时间的互作方面，0．15％的秋水仙素处理24h，细胞的中期分裂指数最高，达到0．202％；而0．15％的秋水仙素处理36h，细胞加倍指数最高，达到0．096％。     

Bio-efficacy of the Essential Oil of Oregano (<Emphasis Type="Italic">Origanum vulgare</Emphasis> Lamiaceae. Ssp. <Emphasis Type="Italic">Hirtum</Emphasis>)

The aim of this study was to investigate the bioactivity of the essential oil isolated from Origanum vulgare L. (EOv). We analyzed the in vivo anti-inflammatory properties in a mouse-airway inflammation model and the in vitro antimicrobial activity, genotoxicity over the anaphase-telophase with the Allium cepa strain and its cytotoxicity/viability in A549 culture cells. In vivo, EOv modified the levels of tumor necrosis factor -α and viable activated macrophages and was capable to mitigate the effects of degradation of conjugated dienes. In vitro, EOv reduced the viability of cultured A549 cells as well as the mitotic index and a number of chromosomal aberrations; however, it did not change the number of phases. We found that EOv presents antimicrobial activity against different Gram (?) and (+) strains, measured by disc-diffusion test and confirmed with a more accurate method, the AutoCad software. We postulate that EOv presents antibacterial, antioxidant and chemopreventive properties and could be play an important role as bioprotector agent.     

Plant Extracts of Winter Savory, Purple Coneflower, Buckwheat and Black Elder Activate PPAR-γ in COS-1 Cells but do not Lower Blood Glucose in Db/db Mice In vivo

The aim of this study was to investigate possible blood glucose-lowering effects of plant extracts in vivo for which prior to this a peroxisome proliferator-activated receptor-γ activity in vitro was observed. The ability of extracts of winter savory, purple coneflower, buckwheat and black elder to dose-dependently activate peroxisome proliferator-activated receptor-γ was determined in a reporter gene assay in COS-1 cells. For evaluation of glucose-lowering effects in vivo, db/db mice were fed a diet containing either rosiglitazone (0.02 g/kg diet, positive control) or one of the plant extracts (0.1 and 1 g/kg diet) for four weeks. Apart from glucose, insulin, triacylglycerols, non-esterified fatty acids, cholesterol and adiponectin were determined in plasma. All plant extracts showed a dose-dependent peroxisome proliferator-activated receptor-γ-activating effect in vitro. In db/db mice none of the plant extracts exerted glucose-lowering effects at the used dosages compared to rosiglitazone. Non-esterified fatty acids, triacylglycerols, cholesterol, insulin and adiponectin in plasma were not altered by the plant extracts as well. Although dose-dependent peroxisome proliferator-activated receptor-γ activity could be shown in COS-1 cells, the experiments in db/db mice lacked to confirm any anti-diabetic effect of the plant extracts in vivo and emphasizes the importance of verifying cell culture data using an appropriate in vivo model.     

Anti-phytopathogenic activities of macro-algae extracts

Aqueous and ethanolic extracts obtained from nine Chilean marine macro-algae collected at different seasons were examined in vitro and in vivo for properties that reduce the growth of plant pathogens or decrease the injury severity of plant foliar tissues following pathogen infection. Particular crude aqueous or organic extracts showed effects on the growth of pathogenic bacteria whereas others displayed important effects against pathogenic fungi or viruses, either by inhibiting fungal mycelia growth or by reducing the disease symptoms in leaves caused by pathogen challenge. Organic extracts obtained from the brown-alga Lessonia trabeculata inhibited bacterial growth and reduced both the number and size of the necrotic lesion in tomato leaves following infection with Botrytis cinerea. Aqueous and ethanolic extracts from the red-alga Gracillaria chilensis prevent the growth of Phytophthora cinnamomi, showing a response which depends on doses and collecting-time. Similarly, aqueous and ethanolic extracts from the brown-alga Durvillaea antarctica were able to diminish the damage caused by tobacco mosaic virus (TMV) in tobacco leaves, and the aqueous procedure is, in addition, more effective and seasonally independent. These results suggest that macro-algae contain compounds with different chemical properties which could be considered for controlling specific plant pathogens.     

An alternative pretreatment method for mitotic chromosome observation in potatoes

An alternative pretreatment method for mitotic chromosomes in potato root tips is described. Root tips were treated with a synthetic pyrethroid, a permethrine, {3-Phenoxybenzil (±) -Cis, trans, 3-(2,2 dichlorovinyl) -2,2-dimethyl ciclopropane carboxylate}. with concentrations of 10ppm, 100ppm, 200ppm, and 500ppm. Cold water and 0.02M 8-hydroxyquinoline were used for comparison at 4 C. Mitotic index was obtained for all treatments by using a standard squash method, and pretreatment with 100ppm of the pyrethroid demonstrated a large number of mitotic cells and well condensed chromosomes for a comprehensive observation in mitotic cells     

Imaging genome abnormalities in cancer research

Increasing attention is focusing on chromosomal and genome structure in cancer research due to the fact that genomic instability plays a principal role in cancer initiation, progression and response to chemotherapeutic agents. The integrity of the genome (including structural, behavioral and functional aspects) of normal and cancer cells can be monitored with direct visualization by using a variety of cutting edge molecular cytogenetic technologies that are now available in the field of cancer research. Examples are presented in this review by grouping these methodologies into four categories visualizing different yet closely related major levels of genome structures. An integrated discussion is also presented on several ongoing projects involving the illustration of mitotic and meiotic chromatin loops; the identification of defective mitotic figures (DMF), a new type of chromosomal aberration capable of monitoring condensation defects in cancer; the establishment of a method that uses Non-Clonal Chromosomal Aberrations (NCCAs) as an index to monitor genomic instability; and the characterization of apoptosis related chromosomal fragmentations caused by drug treatments.     

Anti-Leukemic Properties of Aplysinopsin Derivative EE-84 Alone and Combined to BH3 Mimetic A-1210477

Aplysinopsins are a class of marine indole alkaloids that exhibit a wide range of biological activities. Although both the indole and N-benzyl moieties of aplysinopsins are known to possess antiproliferative activity against cancer cells, their mechanism of action remains unclear. Through in vitro and in vivo proliferation and viability screening of newly synthesized aplysinopsin analogs on myelogenous leukemia cell lines and zebrafish toxicity tests, as well as analysis of differential toxicity in noncancerous RPMI 1788 cells and PBMCs, we identified EE-84 as a promising novel drug candidate against chronic myeloid leukemia. This indole derivative demonstrated drug-likeness in agreement with Lipinski’s rule of five. Furthermore, EE-84 induced a senescent-like phenotype in K562 cells in line with its cytostatic effect. EE-84-treated K562 cells underwent morphological changes in line with mitochondrial dysfunction concomitant with autophagy and ER stress induction. Finally, we demonstrated the synergistic cytotoxic effect of EE-84 with a BH3 mimetic, the Mcl-1 inhibitor A-1210477, against imatinib-sensitive and resistant K562 cells, highlighting the inhibition of antiapoptotic Bcl-2 proteins as a promising novel senolytic approach against chronic myeloid leukemia.     

Evaluation of growth inhibitory and apoptosis inducing activity of human calprotectin on the human gastric cell line (AGS)

BACKGROUND: Calprotectin is cytotoxic agent that its anti-tumor effects are governed through suppression of topoisomerase II; a key enzyme in apoptosis. In previous studies, cytotoxicity and apoptotic effects of calprotectin are shown on different cancer cell lines, but not human gastric cancer cell lines. In the present study, cytotoxicity and apoptotic effects of calprotectin on human gastric adenocarcinoma cancer cell line (AGS) were evaluated. METHODS: The AGS cells were exposed to the different concentrations of calprotectin for 24, 48 and 72 hours. Cell proliferation was assessed using dimethylthiazol diphenyl tetrazolium bromide assay and dye exclusion tests. For evaluation of cytotoxic mechanism in calprotectin on AGS cells, flow cytometric analysis was performed. RESULTS: Our results revealed that calprotectin induces growth inhibition of AGS in a dose- and time-dependent manner. Results of this investigation showed that sensitivity of AGS cells to cytotoxic effect of human calprotectin was highly remarkable. In addition, growth inhibitory effect of this cytotoxic agent mostly was governed through induction of apoptosis in the AGS cells. CONCLUSION: These findings indicated that calprotectin induces growth inhibition and apoptosis in the AGS cells.     

Antiprotozoal activities of organic extracts from French marine seaweeds

Marine macrophytes contain a variety of biologically active compounds, some reported to have antiprotozoal activity in vitro. As a part of a screening program to search for new natural antiprotozoals, we screened hydroalcoholic and ethyl acetate extracts of 20 species of seaweeds from three phyla (Rhodophyta, Heterokontophyta and Chlorophyta), sampled along the Normandy (France) coast. We tested them in vitro against the protozoa responsible for three major endemic parasitic diseases: Plasmodium falciparum, Leishmania donovani and Trypanosoma cruzi. The selectivity of the extracts was also evaluated by testing on a mammalian cell line (L6 cells). Ethyl acetate extracts were more active than hydroalcoholic ones. Activity against T. cruzi and L. donovani was non-existent to average, but almost half the extracts showed good activity against P. falciparum. The ethyl acetate extract of Mastocarpus stellatus showed the best antiplasmodial activity as well as the best selectivity index (IC(50) = 2.8 μg/mL; SI > 30). Interestingly, a red algae species, which shares phylogenetic origins with P. falciparum, showed the best antiplasmodial activity. This study is the first to report comparative antiprotozoal activity of French marine algae. Some of the species studied here have not previously been biologically evaluated.     

Isolation of a new natural product and cytotoxic and antimicrobial activities of extracts from fungi of Indonesian marine habitats

In the search for bioactive compounds, 11 fungal strains were isolated from Indonesian marine habitats. Ethyl acetate extracts of their culture broth were tested for cytotoxic activity against a urinary bladder carcinoma cell line and for antifungal and antibacterial activities against fish and human pathogenic bacteria as well as against plant and human pathogenic fungi. The crude extract of a sterile algicolous fungus (KT31), isolated from the red seaweed Kappaphycus alvarezii (Doty) Doty ex P.C. Silva exhibited potent cytotoxic activity with an IC₅₀ value of 1.5 μg/mL. Another fungal strain (KT29) displayed fungicidal properties against the plant pathogenic fungus Cladosporium cucumerinum Ell. et Arth. at 50 μg/spot. 2-Carboxy-8-methoxy-naphthalene-1-ol (1) could be isolated as a new natural product.     

Some morphological and anatomical studies of leaves and flowers of Murraya paniculata (Jack) Linn. in vivo and in vitro

In the present study, various explants of Murraya paniculata (Jack) Linn., such as cotyledons, shoots and young stems were cultured on MS medium supplemented with various concentrations of Benzyl Amino Purine (BAP) under 25 +/- 1 degree C with 16 h light and 8 h dark and also 8 h light and 16 h dark to obtain complete plant regeneration. In vitro flowering was observed from shoot explants cultured on MS supplemented with 0.5-2.0 mg L(-1) Naphthalene Acetic Acid (NAA) and also on MS basal medium under similar conditions. The leaves and flowers obtained from both in vivo and in vitro conditions were examined and compared. Morphological studies such as leaf clearing, epidermal peeling were studied using light and scanning electron microscope. Macromorphological studies of the flowers produced from in vivo and in vitro conditions were also examined. Morphologically, there were no differences between in vivo and in vitro flowers except the flowers produced from tissue culture systems were smaller in size with protruding stigmas. Differences were also found in the number of layers of palisade cells and the presence or absence of epicuticle layer of the leaves. Leaves produced from tissue culture system were smaller in size with membranous texture. Stomata were present only on the abaxial surfaces of both in vivo and in vitro leaves but the stomata were raised above the epidermis in the latter.     

Antioxidant Bioactivity of Extracts from Beach Cast Leaves of Posidonia oceanica (L.) Delile

The marine environment is a generous source of biologically active compounds useful for human health. In 50 years, about 25,000 bioactive marine compounds have been identified, with an increase of 5% per year. Peculiar feature of algae and plants is the production of secondary metabolites, such as polyphenols, synthesized as a form of adaptation to environmental stress. Posidonia oceanica is a Mediterranean endemic and dominant seagrass and represents a biologically, ecologically and geologically important marine ecosystem. Within this study, methanolic and ethanolic extracts were generated from fresh and dried Posidonia oceanica leaves, with the aim to employ and valorize the beach cast leaves. The best yield and antioxidant activity (polyphenols content equal to 19.712 ± 0.496 mg GAE/g and DPPH IC50 of 0.090 µg/µL.) were recorded in 70% ethanol extracts (Gd-E4) obtained from leaves dried for two days at 60 °C and ground four times. HPLC analyses revealed the presence of polyphenols compounds (the most abundant of which was chicoric acid) with antioxidant and beneficial properties. Bioactive properties of the Gd-E4 extracts were evaluated in vitro using fibroblast cells line (HS-68), subjected to UV induced oxidative stress. Pre-treatment of cells with Gd-E4 extracts led to significant protection against oxidative stress and mortality associated with UV exposure, thus highlighting the beneficial properties of antioxidants compounds produced by these marine plants against photo damage, free radicals and associated negative cellular effects. Beach cast leaves selection, processing and extraction procedures, and the in vitro assay results suggested the potentiality of a sustainable approach for the biotechnological exploitation of this resource and could serve a model for other marine resources.     

Antimicrobial and cytotoxic assessment of marine cyanobacteria - Synechocystis and Synechococcus

Aqueous extracts and organic solvent extracts of isolated marine cyanobacteria strains were tested for antimicrobial activity against a fungus, Gram-positive and Gram-negative bacteria and for cytotoxic activity against primary rat hepatocytes and HL-60 cells. Antimicrobial activity was based on the agar diffusion assay. Cytotoxic activity was measured by apoptotic cell death scored by cell surface evaluation and nuclear morphology. A high percentage of apoptotic cells were observed for HL-60 cells when treated with cyanobacterial organic extracts. Slight apoptotic effects were observed in primary rat hepatocytes when exposed to aqueous cyanobacterial extracts. Nine cyanobacteria strains were found to have antibiotic activity against two Gram-positive bacteria, Clavibacter michiganensis subsp. insidiosum and Cellulomonas uda. No inhibitory effects were found against the fungus Candida albicans and Gram-negative bacteria. Marine Synechocystis and Synechococcus extracts induce apoptosis in eukaryotic cells and cause inhibition of Gram-positive bacteria. The different activity in different extracts suggests different compounds with different polarities.     

Anti-Proliferative Properties,Biocompatibility, and Chemical Composition of Different Extracts of Plantago major Medicinal Plant

Background:To study the anticancer activity of Plantago major, we assessed the effect of ethanolic, methanolic and acetonic extracts of this plant on HCT-116, SW-480, and HEK-293 cell lines as control. Methods:The cytotoxic activity, biocompatibility, and toxicity were evaluated by MTT assay, hemolysis, and Artemia salina-LD₅₀ (on mice) tests, respectively. The analysis of the extracts was performed by GC-MS analysis. Results:The results showed that all the extracts had the most antiproliferative properties on the HCT-116 cell line. The P. major root extract was more effective than the aerial parts, and IC₅₀ values for ethanolic, methanolic and acetonic root extracts were 405.59, 470.16, and 82.26 µg/mL, respectively on HCT-116 cell line at 72 h. Hemolysis degree of the ethanolic extract of aerial and root parts were approximately 1% at 400 μg/mL.. Using the ethanolic extracts, the Artemia survived every concentration, and no toxicity was observed. One week after the oral administration of different parts of P. major extracts, none of the mice died, even those were administered 2000 mg/kg. The results of GC/MS analysis showed that P. major extracts contain potential anticancer compounds, such as stearic acid (8.61%) in aerial parts of methanolic extract and 1,2- Benzenedicarboxylic acid, mono(2-ethylhexyl)ester (88.07% and 40.63%) in aerial and root parts of acetonic extract of P. major. Conclusions:Our findings suggest that the P. major is a source of potential compounds with antiproliferative properties. Key Words: Gas chromatography-mass spectrometry, HCT-116 cells, Hemolysis, Lethal dose 50