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111.
This paper introduces and studies a new generalization of cumulative past extropy called weighted cumulative past extropy (WCPJ) for continuous random variables. We explore the following: if the WCPJs of the last order statistic are equal for two distributions, then these two distributions will be equal. We examine some properties of the WCPJ, and a number of inequalities involving bounds for WCPJ are obtained. Studies related to reliability theory are discussed. Finally, the empirical version of the WCPJ is considered, and a test statistic is proposed. The critical cutoff points of the test statistic are computed numerically. Then, the power of this test is compared to a number of alternative approaches. In some situations, its power is superior to the rest, and in some other settings, it is somewhat weaker than the others. The simulation study shows that the use of this test statistic can be satisfactory with due attention to its simple form and the rich information content behind it. 相似文献
112.
Nidal Jaradat Mohammed Hawash Mohammad Qadi Murad Abualhasan Aseel Odetallah Ghfran Qasim Reem Awayssa Amna Akkawi Ibtesam Abdullah Nawaf Al-Maharik 《Molecules (Basel, Switzerland)》2022,27(17)
Pelargonium graveolens leaves are widely used in traditional medicine for relieving some cardiovascular, dental, gastrointestinal, and respiratory disorders. They are also used as food and tea additives in Palestine and many other countries. Consequently, this investigation aimed to describe the chemical markers, cytotoxic, antioxidant, antimicrobial, metabolic, and cyclooxygenase (COX) enzymes inhibitory characteristics of P. graveolens essential oil (PGEO) from Palestine utilizing reference methods. There were 70 chemicals found in the GCMS analysis, and oxygenated terpenoids were the most abundant group of the total PGEO. Citronellol (24.44%), citronellyl formate (15.63%), γ-eudesmol (7.60%), and iso-menthone (7.66%) were the dominant chemical markers. The EO displayed strong antioxidant activity (IC50 = 3.88 ± 0.45 µg/mL) and weak lipase and α-amylase suppressant effects. Notably, the PGEO displayed high α-glucosidase inhibitory efficacy compared with Acarbose, with IC50 doses of 52.44 ± 0.29 and 37.15 ± 0.33 µg/mL, respectively. PGEO remarkably repressed the growth of methicillin-resistant Staphylococcus aureus (MRSA), even more than Ampicillin and Ciprofloxacin, and strongly inhibited Candida albicans compared with Fluconazole. The highest cytotoxic effect of the PGEO was noticed against MCF-7, followed by Hep3B and HeLa cancer cells, with IC50 doses of 32.71 ± 1.25, 40.71 ± 1.89, and 315.19 ± 20.5 µg/mL, respectively, compared with doxorubicin. Moreover, the screened EO demonstrated selective inhibitory activity against COX-1 (IC50 = 14.03 µg/mL). Additionally, PGEO showed a weak suppressant effect on COX-2 (IC50 = 275.97 µg/mL). The current research can be considered the most comprehensive investigation of the chemical and pharmacological characterization of the PGEO. The results obtained in this study demonstrate, without doubt, that this plant represents a rich source of bioactive substances that can be further investigated and authenticated for their medicinal potential. 相似文献
113.
114.
Mohammad B. Haskali Peter D. Roselt Terence J. OBrien Craig A. Hutton Idrish Ali Lucy Vivash Bianca Jupp 《Molecules (Basel, Switzerland)》2022,27(18)
(1) Background: [18F]Flumazenil 1 ([18F]FMZ) is an established positron emission tomography (PET) radiotracer for the imaging of the gamma-aminobutyric acid (GABA) receptor subtype, GABAA in the brain. The production of [18F]FMZ 1 for its clinical use has proven to be challenging, requiring harsh radiochemical conditions, while affording low radiochemical yields. Fully characterized, new methods for the improved production of [18F]FMZ 1 are needed. (2) Methods: We investigate the use of late-stage copper-mediated radiofluorination of aryl stannanes to improve the production of [18F]FMZ 1 that is suitable for clinical use. Mass spectrometry was used to identify the chemical by-products that were produced under the reaction conditions. (3) Results: The radiosynthesis of [18F]FMZ 1 was fully automated using the iPhase FlexLab radiochemistry module, affording a 22.2 ± 2.7% (n = 5) decay-corrected yield after 80 min. [18F]FMZ 1 was obtained with a high radiochemical purity (>98%) and molar activity (247.9 ± 25.9 GBq/µmol). (4) Conclusions: The copper-mediated radiofluorination of the stannyl precursor is an effective strategy for the production of clinically suitable [18F]FMZ 1. 相似文献
115.
Leili Mohammadi Hossein Kamani Abolfazl Asghari Amin Mohammadpour Mohammad Golaki Abbas Rahdar George Z. Kyzas 《Molecules (Basel, Switzerland)》2022,27(19)
High concentrations of antibiotics have been identified in aqueous media, which has diminished the quality of water resources. These compounds are usually highly toxic and have low biodegradability, and there have been reports about their mutagenic or carcinogenic effects. The aim of this study was to apply zero-valent iron-oxide nanoparticles in the presence of hydrogen peroxide and the sonolysis process for the removal of the amoxicillin antibiotic from aqueous media. In this study, zero-valent iron nanoparticles were prepared by an iron chloride reduction method in the presence of sodium borohydride (NaBH4), and the obtained nanoparticles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and vibrating-sample magnetometry (VSM). Then, using a Fenton-like process, synthetic wastewater containing 100 to 500 mg/L amoxicillin antibiotic was investigated, and the effects of different parameters, such as the frequency (1 and 2 kHz), contact time (15 to 120 min), the concentration of hydrogen peroxide (0.3%, 0.5%, and 6%), the dose of zero-valent iron nanoparticles (0.05, 0.1, 0.5 g/L), and pH (3, 5, 10) were thoroughly studied. A pH of 3, hydrogen peroxide concentration of 3%, ultrasonic-wave frequency of 130 kHz, zero-valent iron nanoparticles of 0.5 g/L, and contaminant concentration of 100 mg/L were obtained as the optimal conditions of the combined US/H2O2/nZVI process. Under the optimal conditions of the combined process of zero-valent iron nanoparticles and hydrogen peroxide in the presence of ultrasonic waves, a 99.7% removal efficiency of amoxicillin was achieved in 120 min. The results show that the combined US/H2O2/nZVI process could be successfully used to remove environmental contaminants, including antibiotics such as amoxicillin, with a high removal percentage. 相似文献
116.
Yi-Dan Zheng Li-Mei Ma Jin-Jian Lu Tian Chai Mohammad Reza Naghavi Jun-Yi Ma Chun-Yan Sang Jun-Li Yang 《Molecules (Basel, Switzerland)》2022,27(20)
Pancreatic cancer is the seventh leading cause of cancer-related death worldwide and is known as “the king of cancers”. Currently, gemcitabine (GEM) as the clinical drug of choice for chemotherapy of advanced pancreatic cancer has poor drug sensitivity and ineffective chemotherapy. Nardoguaianone L (G-6) is a novel guaiane-type sesquiterpenoid isolated from Nardostachys jatamansi DC., and it exhibits anti-tumor activity. Based on the newly discovered G-6 with anti-pancreatic cancer activity in our laboratory, this paper aimed to evaluate the potential value of the combination of G-6 and GEM in SW1990 cells, including cell viability, cell apoptosis, colony assay and tandem mass tags (TMT) marker-based proteomic technology. These results showed that G-6 combined with GEM significantly inhibited cell viability, and the effect was more obvious than that with single drug. In addition, the use of TMT marker-based proteomic technology demonstrated that the AGE-RAGE signaling pathway was activated after medication-combination. Furthermore, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) assays were used to validate the proteomic results. Finally, apoptosis was detected by flow cytometry. In conclusion, G-6 combined with GEM induced an increase in ROS level and a decrease in MMP in SW1990 cells through the AGE-RAGE signaling pathway, ultimately leading to apoptosis. G-6 improved the effect of GEM chemotherapy and may be used as a potential combination therapy for pancreatic cancer. 相似文献
117.
Lei Yang Mohammad Javad Afshari Jianxian Ge Dandan Kou Lei Chen Dandan Zhou Cang Li Shuwang Wu Leshuai Zhang Jianfeng Zeng Jian Zhong Roland H. Stauber Mingyuan Gao 《Molecules (Basel, Switzerland)》2022,27(20)
Hypoxia is a common biological condition in many malignant solid tumors that plays an imperative role in regulating tumor growth and impacting the treatment’s therapeutic effect. Therefore, the hypoxia assessment is of great significance in predicting tumor development and evaluating its prognosis. Among the plenty of existing tumor diagnosis techniques, magnetic resonance imaging (MRI) offers certain distinctive features, such as being free of ionizing radiation and providing images with a high spatial resolution. In this study, we develop a fluorescent traceable and hypoxia-sensitive T1-weighted MRI probe (Fe3O4-Met-Cy5.5) via conjugating notable hypoxia-sensitive metronidazole moiety and Cy5.5 dye with ultrasmall iron oxide (Fe3O4) nanoparticles. The results of in vitro and in vivo experiments show that Fe3O4-Met-Cy5.5 has excellent performance in relaxivity, biocompatibility, and hypoxia specificity. More importantly, the obvious signal enhancement in hypoxic areas indicates that the probe has great feasibility for sensing tumor hypoxia via T1-weighted MRI. These promising results may unlock the potential of Fe3O4 nanoparticles as T1-weighted contrast agents for the development of clinical hypoxia probes. 相似文献
118.
Bandar Ali Al-Asbahi Mohamad S. AlSalhi Mohammad Hafizuddin Hj. Jumali Amanullah Fatehmulla Saif M. H. Qaid Wafa Musa Mujamammi Hamid M. Ghaithan 《Molecules (Basel, Switzerland)》2022,27(20)
The improvement of optical and optoelectronic properties of the individual poly [2-methoxy-5- (2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV), poly[2-methoxy-5-(3,7-dimethyl-octyloxy)-1,4-phenylenevinylene]–End capped with Dimethyl phenyl (OC1C10–PPV–DMP), and poly (9,9′-di- n -octylfluorenyl-2,7-diyl) (F8) was revealed by blending them in ternary hybrid with optimal ratio (F8/2 wt.% MEH-PPV/2 wt.% OC1C10–PPV–DMP). All individual and optimal ternary solutions were prepared via the solution-blending method followed by depositing them onto glass and ITO substrates using spin-coating technique. The semi-crystalline phase of the ternary hybrid and the strong mixing between the conjugated polymers were evidenced by observing the X-ray diffraction patterns that related to F8 into the hybrid diffractogram. The optical and optoelectronic properties of all prepared thin films were investigated in terms of absorption and emission spectra, Commission International d′Eclairage (CIE) coordinates, and current–voltage (I-V) characterizations. Emission peaks at the entire range of visible spectrum can be revealed from the ternary hybrid of the three individual conjugated polymers, producing white emission as evidenced from the emission spectrum and CIE coordinates of the hybrid. Among all fabricated organic light-emitting diodes (OLEDs) devices, the ternary hybrid-based-OLED revealed the best performance in terms of current and turn-on voltage. 相似文献
119.
Jing Yan Takumi Sakamoto Ariful Islam Yashuang Ping Soho Oyama Hiroyuki Fuchino Hitomi Kawakami Kayo Yoshimatsu Tomoaki Kahyo Mitsutoshi Setou 《Molecules (Basel, Switzerland)》2022,27(20)
The global population is aging, and intervention strategies for anti-aging and the prevention of aging-related diseases have become a topic actively explored today. Nicotinamide adenine dinucleotide (NAD+) is an important molecule in the metabolic process, and its content in tissues and cells decreases with age. The supplementation of nicotinamide mononucleotide (NMN), an important intermediate and precursor of NAD+, has increased NAD+ levels, and its safety has been demonstrated in rodents and human studies. However, the high content of NMN in natural plants has not been fully explored as herbal medicines for drug development. Here, we identified that the leaf of Cinnamomum verum J. Presl (C. verum) was the highest NMN content among the Plant Extract Library (PEL) with food experience, using ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS). To validate this result, the extraction and quantitative analysis of bark, leaf, root, and stem of fresh C. verum was conducted. The results revealed that the bark had the highest NMN content in C. verum (0.471 mg/100 g). Our study shed light on the prospects of developing natural plants in the context of NMN as drugs for anti-aging and prevention of aging-related diseases. The future should focus on the development and application of C. verum pharmaceutical formulations. 相似文献
120.
Nagaraja Sreeharsha Samathoti Prasanthi Satyavarapu Veera Venkata Naga Satya Mahalakshmi Prakash S. Goudanavar Nimbagal Raghavendra Naveen Buduru Gowthami Santosh Fattepur Girish Meravanige Syed Mohammed Basheeruddin Asdaq Md. Khalid Anwer Bandar Aldhubiab Mohammed Monirul Islam Mohammed Habeebuddin Mallikarjun Telsang Mazen Al Gharsan Michelyne Haroun 《Molecules (Basel, Switzerland)》2022,27(22)
A brand-new nano-crystal (NC) version of the hydrophobic drug Paclitaxel (PT) were formulated for cancer treatment. A stable NC formulation for the administration of PT was created using the triblock co-polymer Pluronic F127. To achieve maximum entrapment effectiveness and minimal particle size, the formulation was improved using the central composite design by considering agitation speed and vacuum pressure at five levels (coded as +1.414, +1, 0, −1, and −1.414). According to the Design Expert software’s predictions, 13 runs were created and evaluated for the chosen responses. The formulation prepared with an agitation speed of 1260 RPM and a vacuum pressure of 77.53 mbar can meet the requirements of the ideal formulation in order to achieve 142.56 nm of PS and 75.18% EE, according to the level of desirability (D = 0.959). Folic acid was conjugated to Pluronic F127 to create folate receptor-targeted NC. The drug release profile of the nano-crystals in vitro demonstrated sustained release over an extended period. Folate receptor (FR)-targeted NC (O-PT-NC-Folate) has also been prepared by conjugating folic acid to Pluronic F127. MTT test is used to validate the targeting efficacy on the FR-positive human oral cancer cell line (KB). At pharmacologically relevant concentrations, the PT nano-crystal formulation did not cause hemolysis. Compared to non-targeted NC of PT, the O-PT-NC-Folate showed a comparable but more sustained anti-cancer effect, according to an in vivo anti-tumor investigation in NCI/ADR-RES cell lines. The remarkable anti-tumor effectiveness, minimal toxicity, and simplicity of scale-up manufacturing of the NC formulations indicate their potential for clinical development. Other hydrophobic medications that are formulated into nano-systems for improved therapy may benefit from the formulation approach. 相似文献