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11.
Experiments were designed to examine if Actinomycin D, an antibiotic, and Amica 30, a homeopathic drug used against shock and injury, can ameliorate cytogenetic damage induced by single or multiple exposures to ultrasonication. Separate sets of healthy mice were directly exposed to sonication for two minutes either once or they received multiple exposures at an interval of 20 days. The mice were then assessed at different intervals, against suitable controls, using parameters like chromosome aberrations (CA), mitotic index (MI), sperm head anomaly (SHA) and micronucleated erythrocytes (MNE). Separate groups of sonicated mice were either orally administered with Arnica 30 (alcohol 30 in control) or injected intramuscularly with Actinomycin-D (AMD). Elevated frequencies of CA, MI, MNE and SHA were noted in sonicated series. AMD had genotoxic effects of its own and also had additive effects on sonication induced genotoxicity. Sonicated mice fed with Arnica 30 showed appreciably reduced genotoxicity as against alcohol 30 and distilled water fed controls, thereby showing ameliorating effect which may have human application.  相似文献   
12.
The changes in the contents of cyclic AMP, cyclic GMP, ATP, ADP, AMP and fructose-2,6-bisphosphate that occur in the mantle tissue of the mussel Mytilus galloprovincialis Lmk were analysed with regard to the annual gametogenic cycle. Throughout 2 years, the lowest contents of AMP, ADP and ATP were detected during late winter-spring, whereas the maximum appeared in the autumn months. During the second year, fructose-2,6-bisphosphate and cAMP showed a very similar behaviour. The levels of both compounds rose throughout the year until a maximum in September. Their behaviour was also similar to that observed during the first year, but displaced in time. Both in 1998 and in 1999, the highest level of cGMP was detected during the spring-summer months. The results obtained suggest that the glycolytic pathway, with regard to the breeding cycle, might be regulated by fructose-2,6-bisphosphate and cyclic AMP through the activation of 6-phosphofructo-1-kinase, which is the main regulating enzyme of the glycolysis in mantle of M. galloprovincialis.  相似文献   
13.
Anabas testudineus (2n = 46) had the more conserved pattern of its C-heterochromatin distributed mainly in the centromeric region, whereas Puntius sarana (2n = 50) exhibited a rather unorthodox pattern, many chromosomes showing interstitial, some telomeric and a few chromosomes showing centromeric C-band localization. Further, lateral asymmetry in distribution of heterochromatin was also noted in two pairs of chromosomes in P. sarana. The possible implications of the differential distribution noted in these two species has been discussed.  相似文献   
14.
Gonolobus condurango plant extract is used as an anticancer drug in some traditional systems of medicine including homeopathy, but it apparently lacks any scientific validation. Further, no detailed study is available to suggest whether condurango-glycoside-A (CGA), a major ingredient of condurango serves as a potent anticancer compound. Therefore, we investigated apoptosis-inducing ability of CGA against cervix carcinoma cells (HeLa). β-galactosidase-activity and DNA damage were critically studied at different time points; while induced DNA-damage was observed at 9–12th hours, senescence of cells appeared at a later stage (18th hour after CGA treatment), implicating thereby a possible role of DNA damage in inducing pre-mature cell senescence. Concurrently, the number of cells undergoing apoptosis increased along with increase in reactive oxygen species (ROS) generation. Expression of p53 was also up-regulated, indicating that apoptosis could have been mediated through p53 pathway. DCHFDA (4′,6-Diamidino-2-phenylindole dihydrochloride) assay, acridine orange/ethidium bromide staining and annexin V/PI assay results collectively confirmed that apoptosis was induced by increased ROS generation. Reduction in proliferation of cells was further evidenced by the cell cycle arrest at G0/G1 stage. Expression profiles of certain relevant genes and proteins like p53, Akt, Bcl-2, Bax, cytochrome c and caspase 3 also provided evidence of ROS mediated p53 up-regulation and further boost in Bax expression and followed by cytochrome c release and activation of caspase 3. Overall results suggest that CGA initiates ROS generation, promoting up-regulation of p53 expression, thus resulting in apoptosis and pre-mature senescence associated with DNA damage.  相似文献   
15.
Genotoxic effects of EMS have been assessed in fish, A. testudineus, using widely accepted cytogenetic protocols like chromosome aberrations, nuclear anomalies in red blood cells and abnormal sperm head morphology. In addition, gel electrophoretic protein profiles and total protein contents in nine selected tissues were analysed for evaluating their utility as potential indicators of genotoxicity. EMS not only caused chromosomal aberrations in somatic cells, nuclear anomalies in red blood cells, and increased incidence of sperm with abnormal head morphology, but also altered significantly both protein profiles and total protein contents in all tissues tested vis-à-vis suitable controls, indicating relevance of protein data in genotoxicity assessment.  相似文献   
16.
In a bid to ascertain the molecular architecture of the silver positive regions (NORs) in chromosomes of three species of fish, namely, Hemibagrus menoda (Hamilton), Sperata seenghala (Sykes) (Fam: Bagridae) and Mastacembelus armatus (Lacep6de) (Fam: Mastacembelidae), an additional staining methodology using a fluorochrome dye (Chromomycin A3) was deployed along with the AgNO3 technique. The nucleolar organizing regions (NORs) were located terminally at the shorter arms (Tp) of one pair of submetacentric chromosomes (No.3) in H. menoda (2n=58), at the longer arms (Tq) of one pair of submetacentric chromosomes (No.5) in S. seenghala (2n=50) and at the shorter arm (Tp) of one pair of homologous submetacentric chromosomes (No.6) in M. armatus (2n=48). Staining with Chromomycin A3 produced bright fluorescing zones in GC-rich heterochromatin of Ag-positive NORs. The results indicate a more general trend of existence of an overlapping region between NOR and GC-rich fluorescing zones, the active sites of rRNA genes (rDNA) in this primitive group of vertebrates although exceptions to this situation has been reported in a couple of extant fish species earlier. More data utilizing such combined methodologies are warranted to understand the structural organization of fish chromosomes more precisely.  相似文献   
17.
The chemical structure of the main fluorescenting compound in the ethanolic extract (mother tincture) of the American yellow jasmine, Gelsemium sempervirens, was determined by employing (1)H nuclear magnetic resonance (NMR), (13)C NMR, mass spectroscopy, high-performance liquid chromatography (HPLC), correlation spectroscopy (COSY), and Fourier transform infrared (FTIR) spectroscopy analyses. Spectrofluorometric analysis has been made of the mother tincture and its agitated serial dilutions (up to 12th potency) prepared according to a homeopathic procedure in which serial, agitated dilutions were made separately in glass and polypropylene containers. The succussions were made by employing three different modes: hand jerk, sonication, and vortexing. The chemical formula of scopoletin, the main fluorescent compound, was determined to be C(10)H(8)O(4) having a molecular weight of 192.17. Significant differences were noted between the remedies prepared in the two types of containers. Further, a comparison between any two methods of agitation revealed significant differences in fluorometric data of remedies at certain potency levels. The biological (anticancer) action of the crude extract, the alkaloid scopoletin, and 2C potency of Gelsemium sp were tested in vitro on the HeLa cell line through fluorescence microscopy, the 3(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, and fluorescent activated cell sorting (FACS). The role of nanoparticles presumably derived from the containers, their orientation, and their interaction with the starting substance during the dynamization process initiated by different modes of agitation could possibly be attributed to the differences noted in the fluorometric data of potencies prepared in the two types of containers and among the three different means of succussion tested.  相似文献   
18.
To examine if chronic oral administration of phenobarbital (PB), a widely used anti-epileptic drug, has any genotoxic and cytotoxic potential in mice, a mammalian model, cytogenetic assays through several endpoints such as chromosome aberrations, induction of micronuclei, mitotic index of bone marrow cells, sperm-head anomaly in testis and enzymatic assays of several toxicity marker enzymes have been conducted by use of standard techniques. Mice of both treated (chronically receiving an oral dose of PB at 1.2 mg/kg bw) and control (without receiving PB) groups were sacrificed at 7, 15, 30, 60, 90 and 120 days for the study with all the above-mentioned protocols. Further, total protein profiles in liver of both control and treated mice were analyzed through the SDS-PAGE technique at day 60. The results of all these studies, when compared with controls, showed that PB has both genotoxic and cytotoxic potential in apparently increasing intensity at longer periods of chronic feeding in mice, which would warrant due consideration in its long-term use on human subjects.  相似文献   
19.
Chinese hamster V79 cell and a cell strain M5, derived from V79 cells and reported to be relatively resistant to gamma-ray, hydrogen peroxide, and N-methyl-N-nitro-N-nitrosoguanidine (MNNG; a potent human carcinogen), were exposed to high LET (7)Li-beam (LET=60 keV/microm) at approximately 90% confluent state in the dose range of 0-1 Gy. Effects of (7)Li-beam exposure on cell survival, micronuclei induction (MN), chromosomal aberrations (CA) and apoptosis were compared in both the cell lines. A dose-dependent decline in survival for both the cell lines was noted, relatively less in M5 cells (mostly p<0.01) indicating greater radio-resistance in this strain. The MN, CA and apoptosis increased in a dose-dependent manner in both V79 and M5 cells. Significant differences in various other parameters between these two cell lines were also noted. The relative intensity of DNA ladder, which is a useful marker for the determination of the extent of apoptosis induction, was much higher in V79 cells. A good correlation between the reduction of the surviving fractions and the increase in frequencies of MN or CA or apoptosis was noted for both the cell lines.  相似文献   
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