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81.
Breast cancer is a prevalent of tumoregenesis in women and reports for the maximum mortality and morbidity in the global. Ginger (Zingiber officinale) is the mainly widespread spice and herbal remedies used in the world. Since antique periods, ginger has been used in Greece, India and China for the curing of upset stomach, nausea, diarrhea, colds, and headaches. The current work was planned to explore the anticancer properties of zingerone (ZO) toward 7,12‐dimethylbenz(a)anthracene (DMBA)‐treated mammary carcinogenesis in Sprague‐Dawley (SD) rats and MCF‐7 mammary cancer cells. The mammary carcinogenesis was produced through a single dosage of DMBA (20 mg/kg bwt) mixed in soya oil (1 mL) administrated intragastrically with a gavage. We found improved concentrations of lipid peroxidation (LOOH and TBARS), carcinoembryonic antigen, lowered levels of enzymatic (CAT, GPx, and SOD), and nonenzymatic (vitamin E, GSH, and vitamin C) antioxidant in mammary tissues and plasma of DMBA‐induced cancer bearing animals. Moreover, augmented concentrations of phase I (Cyt‐b5 and CYP450) and reduced levels of phase II (GR and GST) detoxification microsomal proteins in mammary tissues were noticed. ZO administrations significantly reverted back to all these parameters in this way, showing efficient of anticancer effect. Furthermore, our in vitro study also supported the anticancer effect of the treatment of ZO were noticed loss of cell viability, improved reactive oxygen species formation, and reduced MMP. Furthermore, the status of apoptosis proteins such as Bcl‐2, Bax, and Bid expressions was determined by using Western blot analysis techniques. Overall, these results proposed the anticancer effect of ZO toward DMBA‐induced mammary cancer in SD animals and Michigan cancer foundation‐7 mammary cancer cells.  相似文献   
82.
Zingerone (ZO), an active phenolic agent derived from Zingiber officinale (Ginger), has many pharmacological properties such as antioxidant, antiangiogenic, and antitumor. However, its potential value in cancer and the mechanism by which ZO wields its therapeutic effects remain obscure. Therefore, in this current study, we explored the effects of ZO on suppressing cell proliferation and enhancing apoptosis in colon cancer cells (HCT116). Our results indicated that ZO significantly enhances the production of reactive oxygen species, lipid peroxidation (thiobarbituric acid reactive substance [TBARS]), and loss of cell viability; and reduces mitochondrial membrane potential and antioxidant levels (SOD, CAT, and GSH) in ZO‐treated HCT116 cells in a dose‐dependent (2.5, 5, and 10 µM) manner. Furthermore, ZO induces oxidative stress‐mediated apoptosis as evidenced by apoptotic morphological changes predicted by AO/EtBr, Hoechst staining and further confirmed by comet assay. Moreover, immunoblotting techniques showed that ZO treatment effectively enhances Bax, caspase‐9, and caspase‐3 expressions and decreases the expression of Bcl‐2 in colon cancer cells. Together, our results evidenced that the antitumor effects of ZO reduce cell proliferation and stimulate apoptosis through modulating pro‐ and antiapoptotic molecular events in HCT116 colon cancer cells. Therefore, based on our findings, ZO may be used as a therapeutic agent for the treatment of colon cancer.  相似文献   
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84.
A total of 266 endophytic fungal isolates were recovered from 1019 tissue segments of Glycyrrhiza glabra collected from four different locations in the North-Western Himalayas. The endophytes grouped into 21 genera and 38 different taxa. The host had strong affinity for the genus Phoma, followed by Fusarium. The species richness was highest at the sub-tropical location, followed by the sub-temperate location and the temperate locations, respectively. The tissue specificity of endophytes was also evident. Some endophytes showed potential antimicrobial activity against phyto-pathogens indicating that they may be helpful to the host in evading pathogens. All the endophytic taxa produced the plant growth promoting hormone, indole acetic acid (IAA), though in varying concentrations. None of these endophytes caused any symptoms of disease in co-cultivation with the tissue cultured plants. Further, all the endophytes had a positive influence on the phenolic and flavonoid content of the host. Three endophytes, Stagonosporopsis cucurbitacearum, Bionectria sp. and Aspergillus terreus also increased the host root (rhizome) and shoot growth visibly. Such endophytes are potential candidates for developing endophyte-based technologies for sustainable cultivation and enhanced productivity of G. glabra. This is the first report of community structure and biological properties of fungal endophytes associated with G. glabra.  相似文献   
85.
Trametes ljubarskyi produces multiple laccase isozymes under various physicochemical conditions. During co-cultivation condition Rhodotorula mucilaginosa showed inter-specific interactions with T. ljubarskyi and hypersecretion of laccases; however, the underlying molecular mechanism is less-known. The analysis of proteomics data of co-cultivated cultures revealed the mechanism of metabolic coupling during fungal-yeast interactions. The results suggested high score GO terms related to stimulus-response, protein binding, membrane components, transport channels, oxidoreductases, and antioxidants. The SEM studies confirmed the cellular communication and their inter-specific interactions. This study allows us to deepen and refine our understanding of fungal-yeast symbiotic interaction; further, it also establishes a mutual relation by metabolic coupling for 10-fold higher laccase isozyme secretion (6532 U/ml). The purified laccase isozymes showed acidic pH optima (pH 3–4), higher thermo-stability (60 °C), and broad enzyme kinetics (Km) values. Our study also provides an in-depth understanding of laccase isozymes and their potential to degrade synthetic dyes, which may help the fungi to survive in an adverse environment.  相似文献   
86.
87.
Many bacteria used for biotechnological applications are naturally motile. Their "bio-nanopropeller" driven movement allows searching for better environments in a process called chemotaxis. Since bacteria are extremely small in size compared to the bulk fluid volumes in bioreactors, single cell motility is not considered to influence bioreactor operations. However, with increasing interest in localized fluid flow inside reactors, it is important to ask whether individual motility characteristics of bacteria are important in bioreactor operations. The first step in this direction is to try to correlate single cell measurements with population data of motile bacteria in a bioreactor. Thus, we observed the motility behavior of individual bacterial cells, using video microscopy with 33 ms time resolution, as a function of population growth dynamics of batch cultures in shake flasks. While observing the motility behavior of the most intensively studied bacteria, Escherichia coli, we find that overall bacterial motility decreases with progression of the growth curve. Remarkably, this is due to a decrease in a specific motility behavior called "running". Our results not only have direct implications on biofilm formations, but also provide a new direction in bioprocess design research highlighting the role of individual bacterial cell motility as an important parameter.  相似文献   
88.
Mechanical forces imposed on lung tissue constitute major stimuli for normal lung development and postpneumonectomy (PNX) compensatory growth and remodeling. Superimposing developmental signals on PNX signals augments compensatory alveolar growth but exaggerates airway-parenchymal dissociation (i.e., dysanaptic lung growth); the latter tends to offset benefits derived from the former. In adult dogs after PNX, lobar expansion and growth of the remaining lobes were markedly non-uniform (Ravikumar et al. J Appl Physiol 97:1567-1574, 2004). We hypothesized that superimposing developmental and post-PNX signals further accentuates nonuniformity of lobar growth. We used high-resolution computed tomography (HRCT) to follow regional lung expansion and growth in foxhounds undergoing right PNX at 2.5 mo of age compared with litter-matched control (Sham) animals; scans were performed 4 and 10 mo following surgery, i.e., before and after somatic maturity. Air and tissue volumes were measured in each lobe; tissue volume estimated by HRCT includes air-free tissue and blood in small vessels <1 mm. Interlobar nonuniformity of tissue volume was absent at 4 mo but evident 10 mo after PNX; growth of the remaining left lower lobe gradually lagged behind other lobes. At maturity, nonuniformity of lobar growth in pneumonectomized puppies was similar to that previously reported in pneumonectomized adults. We conclude that superimposing developmental and post-PNX signals enhances some aspects of compensatory lung growth and remodeling without altering its nonuniform spatial distribution.  相似文献   
89.
Phytochemistry Reviews - Triterpenes are naturally occurring derivatives biosynthesized following the isoprene rule of Ruzicka. The triterpenes have been reported to possess a wide range of...  相似文献   
90.
Ant‐lycaenid associations range from mutualism to parasitism and the caterpillars of some species of lycaenids are reported to enter ant nests for shelter, diapause, or pupation. The present study aimed to examine the nature of the association between Euchrysops cnejus (Fabricius) (Lepidoptera: Lycaenidae) and Camponotus compressus (Fabricius) (Hymenoptera: Formicidae) worker ants on the extrafloral nectary‐bearing cowpea plant, Vigna unguiculata (L.) Walp. (Fabaceae). The abundance patterns of the ants and the lycaenid caterpillars together with the spatial patrolling patterns of the ants on the plants revealed that ant abundance increased with the occurrence of the lycaenid caterpillars and the ants preferred the lycaenids over the extrafloral nectar. Camponotus compressus worker ants constructed a shelter at the cowpea plant base after interaction with one or more lycaenid caterpillar(s) and tended the caterpillars and pupae till the emergence of the butterfly. The ant‐constructed shelters (ACSs) inhabited by the minor caste workers (13 ± 1.3 ants per ACS), were utilized by the caterpillars to undergo pupation. The ants confined their activities predominantly to tending the pod‐feeding caterpillars and the solitary pupa within each ACS. It appears that the behavior of the tending worker ants is modulated by the lycaenid vulnerable stages.  相似文献   
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