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91.
Antrodia salmonea is well known in Taiwan as a traditional Chinese medicinal fungus and has demonstrated antioxidant, anti-inflammatory, and anticancer effects. However, the anticancer activity of A. salmonea against human ovarian cancer is still elusive. Therefore, we investigated the antiovarian tumor activity of a fermented culture broth of A. salmonea and exhibits its underlying molecular mechanism. A. salmonea shows a significant effect on cell viability in human ovarian carcinoma (SKOV-3 or A2780) cell lines with an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Increased terminal deoxynucleotidyl transferase dUTP nick-end labeling-positive cells and annexin V–propidium iodide stained cells indicate that A. salmonea induces late apoptosis in SKOV-3 cells. Notably, treatment with A. salmonea induced the following events: Apoptosis; caspase-3, -8, -9 and poly(ADP-ribose) polymerase activation; first apoptosis signal (Fas) and Fas ligand activation; Bid cleavage; and Bax2–B-cell lymphoma 2 dysregulation. The results show that A. salmonea-induced apoptosis was mediated by both mitochondrial and death receptor pathways. An increase in intracellular reactive oxygen species (ROS) was also observed in A. salmonea-treated cells, whereas the antioxidant N-acetylcysteine (NAC) prevented A. salmonea-induced cell death and DNA fragmentation, indicating that A. salmonea-induced apoptosis was mediated by ROS generation. Interestingly, A. salmonea-induced apoptosis is associated with the suppression of human epidermal growth factor receptor-2 (HER-2/neu) and phosphoinositide 3-kinase (PI3K)–protein kinase B (AKT) expression in HER-2/neu overexpressing SKOV-3 cells. NAC significantly prevented A. salmonea-induced HER-2/neu depletion and PI3K/AKT inactivation, indicating that A. salmonea-triggered apoptosis is mediated by ROS-inhibited HER-2/neu signaling cascades. To our knowledge, this is the first report describing the anticancer activity of this potentially beneficial mushroom against human ovarian carcinoma.  相似文献   
92.
Antrodia camphorata (AC) exhibits potential for engendering cell-cycle arrest as well as prompting apoptosis and metastasis inhibition in triple-negative breast cancer (TNBC) cells. We performed the current study to explore the anti-epithelial-to-mesenchymal transition (EMT) properties of fermented AC broth in TNBC cells. Our results illustrated that noncytotoxic concentrations of AC (20–60 μg/ml) reversed the morphological changes (fibroblastic-to-epithelial phenotype) as well as the EMT by upregulating the observed E-cadherin expression. Furthermore, we discovered treatment with AC substantially inhibit the Twist expression in human TNBC (MDA-MB-231) cells as well as in those that were transfected with Twist. In addition, we determined AC to decrease the observed Wnt/β-catenin nuclear translocation through a pathway determined to be dependent on GSK3β. Notably, AC treatment consistently inhibited the EMT by downregulating mesenchymal marker proteins like N-cadherin, vimentin, Snail, ZEB-1, and fibronectin; at that same time upregulating epithelial marker proteins like occludin and ZO-1. Bioluminescence imaging that was executed in vivo demonstrated AC substantially suppressed breast cancer metastasis to the lungs. Notably, we found that western blot analysis confirmed that AC decreased lung metastasis as demonstrated by upregulation of E-cadherin expression in biopsied lung tissue. Together with our results support the anti-EMT activity of AC, indicating AC as having the potential for acting as an anticancer agent for the treatment of human TNBC treatment.  相似文献   
93.
P-type ATPasesrequire both - and -subunits for functionalactivity. Although an -subunit for colonic apical membraneH-K-ATPase (HKc) has been identified and studied, its -subunithas not been identified. We cloned putative -subunit rat colonicH-K-ATPase (HKc) cDNA that encodes a 279-amino-acid protein with asingle transmembrane domain and sequence homology to other rat-subunits. Northern blot analysis demonstrates that this HKc isexpressed in several rat tissues, including distal and proximal colon,and is highly expressed in testis and lung. HKc mRNA abundance is upregulated threefold compared with normal in distal colon but notproximal colon, testis, or lung of K-depleted rats. In contrast, Na-K-ATPase 1 mRNA abundance isunaltered in distal colon of K-depleted rats. Na depletion, which alsostimulates active K absorption in distal colon, does not increaseHKc mRNA abundance. Western blot analyses using a polyclonalantibody raised to a glutathioneS-transferase-HKc fusion proteinestablished expression of a 45-kDa HKc protein in both apical andbasolateral membranes of rat distal colon, but K depletion increasedHKc protein expression only in apical membranes. Physicalassociation between HKc and HKc proteins was demonstrated byWestern blot analysis performed with HKc antibody onimmunoprecipitate of apical membranes of rat distal colon and HKcantibody. Tissue-specific upregulation of this -subunit mRNA inresponse to K depletion, localization of its protein, its upregulationby K depletion in apical membranes of distal colon, and its physicalassociation with HKc protein provide compelling evidence that HKcis the putative -subunit of colonic H-K-ATPase.  相似文献   
94.
Heavy metal contamination due to natural and anthropogenic sources is a global environmental concern. Release of heavy metal without proper treatment poses a significant threat to public health because of its persistence, biomagnification and accumulation in food chain. Non-biodegradability and sludge production are the two major constraints of metal treatment. Microbial metal bioremediation is an efficient strategy due to its low cost, high efficiency and ecofriendly nature. Recent advances have been made in understanding metal--microbe interaction and their application for metal accumulation/detoxification. This article summarizes the potentials of microbes in metal remediation.  相似文献   
95.
While molecular beacons are primarily known as biosensors for the detection of nucleic acids, it has proven possible to adapt other nucleic acid binding species (aptamers) to function in a manner similar to molecular beacons, yielding fluorescent signals only in the presence of a cognate ligand. Unfortunately, engineering aptamer beacons requires a detailed knowledge of aptamer sequence and structure. In order to develop a general method for the direct selection of aptamer beacons we have first developed a selection method for molecular beacons. A pool of random sequence DNA molecules were immobilized via a capture oligonucleotide on an affinity column, and those variants that could be released from the column by a target oligonucleotide were amplified. After nine rounds of selection and amplification the elution characteristics of the population were greatly improved. A fluorescent reporter in the selected beacons was located adjacent to a DABCYL moiety in the capture oligonucleotide; addition of the target oligonucleotide led to release of the capture oligonucleotide and up to a 17-fold increase in fluorescence. Signaling was specific for the target oligonucleotide, and occurred via a novel mechanism, relative to designed molecular beacons. When the target oligonucleotide is bound it can form a stacked helical junction with an intramolecular hairpin in the selected beacon; formation of the intramolecular hairpin in turn leads to release of the capture oligonucleotide. The ability to select molecular beacons may prove useful for identifying available sites on complex targets, such as mRNAs, while the method for selection can be easily generalized to other, non-nucleic acid target classes.  相似文献   
96.
97.
The effect of urea on the oviposition behaviour of culicine vectors of Japanese encephalitis was studied in rice fields. Gravid females had a strong preference for oviposition in urea treated areas in rice fields, while no such preference was exhibited in untreated areas. The egg laying declined in the area where urea treated water surface had a mechanical barrier, which allowed volatile fractions to escape, but prevented contact with the water. Urea was shown to act as an oviposition attractant/stimulant for Culex tritaeniorhynchus, but its role was not clear for Cx. vishnui, as the number of egg rafts obtained for the latter species was low.  相似文献   
98.
The distribution, density and species composition of juvenile shrimps were studied in three mangrove zones of Pichavaram, situated on the southeast coast of India. Nine species of shrimps dominated with Metapenaeus monoceros, M. brevicornis and Penaeus indicus were recorded. This shrimp resource was higher in mangrove-lined waters than that in neritic waters. This field observation was experimentally proved using litter bags. The average catch around the litter bags was 0.80 individuals day–1 for Rhizophora leaves, 1.6 ind. day–1 for Avicennia leaves and 0.16 ind. day–1 in control. In general, abundance of juvenile shrimps was the highest around the leaves that were decomposed for 40 days and colonized with high counts of nitrogen-fixing azotobacters. Finally, a vegetation trap technique using mangrove leaves has been proposed for efficient schooling of juvenile shrimps. There was about 3-fold increase in number of shrimp juveniles around the trap than at control waters.  相似文献   
99.
Selected oil cakes, neem, castor and mahua, were tried independently and in combination with a chemical nematicide (carbofuran 3G) for the management of Pratylenchus delattrei in crossandra under glass house conditions. The neem oil cake was effective compared to other oil cakes used and there was a synergistic effect when the neemcake was coupled with carbofuran 3G in the management of Pratylenchus delattrei. The treatment resulted in better establishment of seedlings, and with increased plant bio-mass and flower yield.  相似文献   
100.
A series of 3-O-acyl, 3-hydrazine, 2-bromo, and 20,29-dibromo betulinic acid derivatives (1-27) have been synthesized and screened for in vitro cytotoxic activity on human cancer cell lines MOLT-4, JurkatE6.1, CEM.CM3, BRISTOL8, U937, DU145, PA-1, A549, and L132. A number of compounds have shown ED(50)<1 microg/mL against the cancer cell lines tested and have shown better cytotoxicity than betulinic acid. Compounds 13, 19, 20, 23, and 27 were the best derivatives and were selected as lead molecules for further development. The structure-activity relationship has been described.  相似文献   
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