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61.
Citra Dewi Adryan Fristiohady Riezki Amalia Nur Kusaira Khairul Ikram Sugeng Ibrahim Muchtaridi Muchtaridi 《Molecules (Basel, Switzerland)》2022,27(12)
Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, having a poor prognosis and rapid metastases. TNBC is characterized by the absence of estrogen, progesterone, and human epidermal growth receptor-2 (HER2) expressions and has a five-year survival rate. Compared to other breast cancer subtypes, TNBC patients only respond to conventional chemotherapies, and even then, with limited success. Shortages of chemotherapeutic medication can lead to resistance, pressured index therapy, non-selectivity, and severe adverse effects. Finding targeted treatments for TNBC is difficult owing to the various features of cancer. Hence, identifying the most effective molecular targets in TNBC pathogenesis is essential for predicting response to targeted therapies and preventing TNBC cell metastases. Nowadays, natural compounds have gained attention as TNBC treatments, and have offered new strategies for solving drug resistance. Here, we report a systematic review using the database from Pubmed, Science Direct, MDPI, BioScince, Springer, and Nature for articles screening from 2003 to 2022. This review analyzes relevant signaling pathways and the prospect of utilizing natural compounds as a therapeutic agent to improve TNBC treatments in the future. 相似文献
62.
I Gede Putu Wirawan Ni Kadek Emi Sintha Dewi Maria Malida Vernandes Sasadara I Gde Nengah Adhilaksman Sunyamurthi I Made Jawi I Nyoman Wijaya Ida Ayu Putri Darmawati I Ketut Suada Anak Agung Keswari Krisnandika 《Molecules (Basel, Switzerland)》2022,27(15)
The studies of the Bulung Boni and Bulung Anggur (Caulerpa spp.) species and secondary metabolites are still very limited. Proper identification will support various aspects, such as cultivation, utilization, and economic interests. Moreover, understanding the secondary metabolites will assist in developing algae-based products. This study aimed to identify these indigenous Caulerpa algae and analyze their bioactive components. The tufA sequence was employed as a molecular marker in DNA barcoding, and its bioactive components were identified using the GC-MS method. The phylogenetic tree was generated in MEGA 11 using the maximum likelihood method, and the robustness of the tree was evaluated using bootstrapping with 1000 replicates. This study revealed that Bulung Boni is strongly connected to Caulerpa cylindracea. However, Bulung Anggur shows no close relationship to other Caulerpa species. GC-MS analysis of ethanolic extracts of Bulung Boni and Bulung Anggur showed the presence of 11 and 13 compounds, respectively. The majority of the compounds found in these algae have been shown to possess biological properties, such as antioxidant, antibacterial, anticancer, anti-inflammation, and antidiabetic. Further study is necessary to compare the data obtained using different molecular markers in DNA barcoding, and to elucidate other undisclosed compounds in these Caulerpa algae. 相似文献
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64.
Hedi Indra Januar Nurrahmi Dewi Fajarningsih Dewi Seswita Zilda Aditya Bramandito Anthony D. Wright 《Natural product research》2015,29(23):2230-2232
Fish serum albumin (FSA) is an aquatic resource that has potential to be developed as nutraceutical. Therefore, research was undertaken to assess albumin levels in the aqueous extract of muscle tissue of several Perciformes commonly available at a local fish market in Indonesia. Three random replicates for each of 17 Perciformes species were collected and assessed for their FSA content by application of a reversed-phase (C4) HPLC analytical method. Results of these analyses showed that the albumin concentration of the extracts was in the range 3.49–12.61 g/L, and that they varied significantly (P < 0.05) between species and families. This finding may mean that FSA levels are species and family dependent, something that could be investigated in future studies. As fishes from the family Scrombidae showed the highest concentration (12.61 g/L) of FSA, they would likely have the most value as a source for production of albumin-based nutritional and/or clinical products. 相似文献
65.
Crystallinity and fluorine substitution effects on the proton conductivity of porous hydroxyapatites
Porous calcium hydroxyapatite (p-HAp) was prepared by wet chemical methods. The poorly crystalline structure and the high surface specific area (235 m2/g) of this hydroxyapatite have effects on the variation of the electrical properties. Good linearity of logarithm of conductivity versus the relative humidity in the range from 19% to 88% (RH) was observed using the complex impedance spectroscopy. The proton conduction was affected by the relative humidity related to H2O adsorption on the material surfaces. The fluorine substitution in p-HAp also modifies the crystalline and the proton conduction properties. 相似文献
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67.
Continuous approximations to the solution of systems of Volterraintegral equations of the first and second kinds are soughtby methods using spline functions of degree m, deficiency-(k1),i.e. in Cmk, and a fixed quadrature rule of degree p-1,p m-1. The resulting method is called an (m, k)-method. Thestability behaviour of the (m, 1)- and the (m, m)-method isstudied for arbitrarily finite m. Also studied is the stabilityof the (m, m-1)-method for second-kind systems. Convergenceresults and asymptotic formulae for the discretization errorare obtained. 相似文献
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69.
Elham S. Aazam Amel F. EL Husseiny Peter B. Hitchcock Jemila M. Alshehri 《Central European Journal of Chemistry》2008,6(2):319-323
A binuclear copper complex [{Cu(L)2}2], C68H48Cu2N4O12C (where L is 4-methyl-7-(salicylideneamino)coumarin), has been synthesized and characterized using elemental analysis, molar
conductance measurements, and infrared, ultraviolet and ESR spectrosopy. The molecular structure of title compound, determined
by single-crystal X-ray diffraction studies, reveals that the two symmetric Cu(L)2 units are associated into a dimer by rather
long Cu...O bonds. The Cu(II) ions are bridged via the phenolic oxygen of one of the monomers and have distorted trigonal
bipyramidal conformation geometry. Within each monomer the two methylsubstituted coumarin skeletons are trans to one another,
but adopt a parallel arrangement with respect to the other monomer. Only half of the complex molecule can be found in the
asymmetric unit, Z′ = 0.5, the other half is generated by the symmetry centre.
相似文献
70.
Achala Bhuwalka Monique D. Ewan Moneim Elshobaki Jared F. Mike Brian Tlach Sumit Chaudhary Malika Jeffries‐EL 《Journal of polymer science. Part A, Polymer chemistry》2016,54(3):316-324
In an effort to design efficient low‐cost polymers for use in organic photovoltaic cells the easily prepared donor–acceptor–donor triad of a either cis‐benzobisoxazole, trans‐benzobisoxazole or trans‐benzobisthiazole flanked by two thiophene rings was combined with the electron‐rich 4,8‐bis(5‐(2‐ethylhexyl)‐thien‐2‐yl)‐benzo[1,2‐b:4,5‐b′]dithiophene. The electrochemical, optical, morphological, charge transport, and photovoltaic properties of the resulting terpolymers were investigated. Although the polymers differed in the arrangement and/or nature of the chalcogens, they all had similar highest occupied molecular orbital energy levels (?5.2 to ?5.3 eV) and optical band gaps (2.1–2.2 eV). However, the lowest unoccupied molecular orbital energy levels ranged from ?3.1 to ?3.5 eV. When the polymers were used as electron donors in bulk heterojunction photovoltaic devices with PC71BM ([6,6]‐phenyl C71‐butyric acid methyl ester) as the acceptor, the trans‐benzobisoxazole polymer had the best performance with a power conversion efficiency of 2.8%. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 316–324 相似文献