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21.
In the recent past, various groups have proposed diverse biocompatible methods for the synthesis of metal nanoparticles (NPs). Besides culture biomass, culture supernatants (CS) are increasingly being explored for the synthesis of NPs; however, with the ever-increasing exploration of various CS in the biofabrication of NPs, it is equally important to explore the potential of various culture media (CMs) in the synthesis of metal NPs. Considering these aspects, in the present investigation, we explore the possible applicability of various CMs in the biofabrication of metal NPs. The synthesis of NPs was primarily followed by UV/VIS spectroscopy, and, thereafter, the NPs were characterized by various physiochemical techniques, including EM, EDX, FT_IR, X-ray diffraction, and DLS measurements, and finally, their anticancer potentialities were investigated against breast cancer. In addition, the NPs were examined in conjunction with artemisinin for therapeutic benefits against aggressive and highly metastatic MDA-MB-231 breast cancer cells. Cumulatively, the results of the present study collated the potentials of various bacterial CMs in the biofabrication of metal NPs and ascertained the efficacy of the as-synthesized silver nanoparticles, especially the combinatorial entity as intriguing breast cancer therapeutics. The data of the present study plausibly assist in advancing the therapeutic applicability of the combinatorial amalgam against aggressive and highly metastatic MDA-MB-231 breast cancer cells.  相似文献   
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Plant Molecular Biology Reporter - The original version of this article unfortunately contained missing information at author’s affiliations. The affiliation address of the author’s...  相似文献   
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Diaryl naphthyl methanes and the corresponding 1, 2, 3, 4- and 5, 6, 7, 8-tetrahydro naphthyl methane derivatives have been synthesized as novel estrogen receptor binding ligands. The secondary and tertiary amino alkoxy derivatives of diaryl naphthyl and tetrahydro naphthyl methane interact with the estrogen receptor to elicit promising estrogenic, antiestrogenic and implantation inhibition activities in rats. The most active compounds in this series are 7, 9 and 20, cent percent active in preventing implantation in rats at 2.5 mgkg(-1) dose.  相似文献   
26.
Wheat root tips express a 73 kDa cognate isoform and a 77 kDa heat-shock-induced isoform of peptidyl prolyl cis-trans isomerase (FK506 binding protein; FKBP) that is part of a chaperone complex with hsp90. The 73 kDa and 77 kDa FKBPs have very similar sequences, differing primarily in the N- and C-terminal 20 amino acids. In order to define the potential functional roles of these proteins, the 73 kDa and 77 kDa FKBPs were localized in root tips using antigen-affinity purified antibodies as a probe. The cognate 73 kDa FKBP is localized in the cytoplasm and appears enriched around the periphery of the early vacuole and vesicles exiting the trans-Golgi. Parallel assays with antibodies directed against tonoplast aquaporin and pyrophosphatase confirmed the association of FKBP with an early vacuole compartment. Sucrose gradient centrifugation analysis of root tip lysates also showed that 73 kDa FKBP is co-fractionated with tonoplast aquaporin and V-ATPase in a light compartment near the top of the gradient. Heat-shock treatment of root tips induces the accumulation of 77 kDa FKBP while the abundance of 73 kDa FKBP remains constant. Quantitative EM immunogold assays of the intracellular distribution of FKBP over an 8 h heat-shock time-course showed that FKBP is initially present in the cytoplasm, but is transported into the nucleus where it accumulates in the nucleoplasm and into specific subnuclear domains. The results of this study show that the intracellular distribution of the high Mr FKBPs in wheat root tips differs at normal and elevated temperatures, indicating different functional roles for the FKBP isoforms.  相似文献   
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Prior epidemiological, prospective intervention, and peripheral and central fatty acid composition studies suggest that omega-3 fatty acid deficiency may be associated with the pathoaetiology of depression and suicide. In the present study, we determined the fatty acid composition of the postmortem prefrontal cortex (PFC) of adolescent male and female suicide victims and age-matched controls. Fatty acid composition (wt% total fatty acids) and concentrations (μmol/g) were determined in the postmortem PFC (Brodmann area 10) of male and female adolescent (aged 13–20 years) suicide victims (n=20) and age-matched controls (n=20) by gas chromatography. None of the major polyunsaturated fatty acids including the principle brain omega-3 fatty acid, docosahexaenoic acid (DHA), monounsaturated fatty acids, or saturated fatty acids differed significantly between adolescent suicide victims and controls before or after segregation by gender. The arachidonic acid (AA, 20:4n-6): DHA ratio and adrenic acid (22:4n-6) composition were negatively correlated with age at death in controls but not in suicides, and males exhibited a greater AA:DHA ratio irrespective of cause-of-death. These results demonstrate that adolescent male and female suicide victims do not exhibit DHA deficits in the postmortem PFC relative to age-matched controls, and suggest that suicide victims do not exhibit the normal age-related decrease in adrenic acid composition and the AA:DHA ratio.  相似文献   
28.
Calcium ion (Ca2+) is a ubiquitous second messenger that transmits various internal and external signals including stresses and, therefore, is important for plants’ response process. Calcineurin B-like proteins (CBLs) are one of the plant calcium sensors, which sense and convey the changes in cytosolic Ca2+-concentration for response process. A search in four leguminous plant (soybean, Medicago truncatula, common bean and chickpea) genomes identified 9 to 15 genes in each species that encode CBL proteins. Sequence analyses of CBL peptides and coding sequences (CDS) suggested that there are nine original CBL genes in these legumes and some of them were multiplied during whole genome or local gene duplication. Coding sequences of chickpea CBL genes (CaCBL) were cloned from their cDNAs and sequenced, and their annotations in the genome assemblies were corrected accordingly. Analyses of protein sequences and gene structures of CBL family in plant kingdom indicated its diverse origin but showed a remarkable conservation in overall protein structure with appearance of complex gene structure in the course of evolution. Expression of CaCBL genes in different tissues and in response to different stress and hormone treatment were studied. Most of the CaCBL genes exhibited high expression in flowers. Expression profile of CaCBL genes in response to different abiotic stresses and hormones related to development and stresses (ABA, auxin, cytokinin, SA and JA) at different time intervals suggests their diverse roles in development and plant defence in addition to abiotic stress tolerance. These data not only contribute to a better understanding of the complex regulation of chickpea CBL gene family, but also provide valuable information for further research in chickpea functional genomics.  相似文献   
29.
BackgroundArtemisinin-based combination therapies are recommended by the World Health Organisation (WHO) as first-line treatment for Plasmodium falciparum malaria, yet medication must be of good quality for efficacious treatment. A recent meta-analysis reported 35% (796/2,296) of antimalarial drug samples from 21 Sub-Saharan African countries, purchased from outlets predominantly using convenience sampling, failed chemical content analysis. We used three sampling strategies to purchase artemisinin-containing antimalarials (ACAs) in Enugu metropolis, Nigeria, and compared the resulting quality estimates.MethodsACAs were purchased using three sampling approaches - convenience, mystery clients and overt, within a defined area and sampling frame in Enugu metropolis. The active pharmaceutical ingredients were assessed using high-performance liquid chromatography and confirmed by mass spectrometry at three independent laboratories. Results were expressed as percentage of APIs stated on the packaging and used to categorise each sample as acceptable quality, substandard, degraded, or falsified.ResultsContent analysis of 3024 samples purchased from 421 outlets using convenience (n=200), mystery (n=1,919) and overt (n=905) approaches, showed overall 90.8% ACAs to be of acceptable quality, 6.8% substandard, 1.3% degraded and 1.2% falsified. Convenience sampling yielded a significantly higher prevalence of poor quality ACAs, but was not evident by the mystery and overt sampling strategies both of which yielded results that were comparable between each other. Artesunate (n=135; 4 falsified) and dihydroartemisinin (n=14) monotherapy tablets, not recommended by WHO, were also identified.ConclusionRandomised sampling identified fewer falsified ACAs than previously reported by convenience approaches. Our findings emphasise the need for specific consideration to be given to sampling frame and sampling approach if representative information on drug quality is to be obtained.  相似文献   
30.

Background

α-Santalol, an active component of sandalwood oil, has shown chemopreventive effects on skin cancer in different murine models. However, effects of α-santalol on cell cycle have not been studied. Thus, the objective of this study was to investigate effects of α-santalol on cell cycle progression in both p53 mutated human epidermoid carcinoma A431 cells and p53 wild-type human melanoma UACC-62 cells to elucidate the mechanism(s) of action.

Methods

MTT assay was used to determine cell viability in A431 cells and UACC-62; fluorescence-activated cell sorting (FACS) analysis of propidium iodide staining was used for determining cell cycle distribution in A431 cells and UACC-62 cells; immunoblotting was used for determining the expression of various proteins and protein complexes involved in the cell cycle progression; siRNA were used to knockdown of p21 or p53 in A431 and UACC-62 cells and immunofluorescence microscopy was used to investigate microtubules in UACC-62 cells.

Results

α-Santalol at 50-100 μM decreased cell viability from 24 h treatment and α-santalol at 50 μM-75 μM induced G2/M phase cell cycle arrest from 6 h treatment in both A431 and UACC-62 cells. α-Santalol altered expressions of cell cycle proteins such as cyclin A, cyclin B1, Cdc2, Cdc25c, p-Cdc25c and Cdk2. All of these proteins are critical for G2/M transition. α-Santalol treatment up-regulated the expression of p21 and suppressed expressions of mutated p53 in A431 cells; whereas, α-santalol treatment increased expressions of wild-type p53 in UACC-62 cells. Knockdown of p21 in A431 cells, knockdown of p21 and p53 in UACC-62 cells did not affect cell cycle arrest caused by α-santalol. Furthermore, α-santalol caused depolymerization of microtubules similar to vinblastine in UACC-62 cells.

Conclusions

This study for the first time identifies effects of α-santalol in G2/M phase arrest and describes detailed mechanisms of G2/M phase arrest by this agent, which might be contributing to its overall cancer preventive efficacy in various mouse skin cancer models.
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