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Comprehensive review on naringenin and naringin polyphenols as a potent anticancer agent Полный текст
2022
Rauf, Abdur | Shariati, Mohammad Ali | Imran, Muhammad | Bashir, Kashif | K̲h̲ān, Shāhid ʻAlī | Mitra, Saikat | Emran, Talha Bin | Badalova, Kamala | Uddin, Md Sahab | Mubarak, Mohammad S. | Aljohani, Abdullah S. M. | Alhumaydhi, Fahad A. | Derkho, Marina | Korpayev, Serdar | Zengin, Gokhan
Though the incidence of several cancers in Western societies is regulated wisely, some cancers such as breast, lung, and colorectal cancer are currently rising in many low- and middle-income countries due to increased risk factors triggered by societal and development problems. Surgery, chemotherapy, hormone, radiation, and targeted therapies are examples of traditional cancer treatment approaches. However, multiple short- and long-term adverse effects may also significantly affect patient prognosis depending on treatment-associated clinical factors. More and more research has been carried out to find new therapeutic agents in natural products, among which the bioactive compounds derived from plants have been increasingly studied. Naringin and naringenin are abundantly found in citrus fruits, such as oranges and grapefruits. A variety of cell signaling pathways mediates their anti-carcinogenic properties. Naringin and naringenin were also documented to overcome multidrug resistance, one of the major challenges to clinical practice due to multiple defense mechanisms in cancer. The effective parameters underlying the anticancer effects of naringenin and naringin include GSK3β inactivation, suppression of the gene and protein activation of NF-kB and COX-2, JAK2/STAT3 downregulation, downregulation of intracellular adhesion molecules-1, upregulation of Notch1 and tyrocite-specific genes, and activation of p38/MAPK and caspase-3. Thus, this review outlines the potential of naringin and naringenin in managing different types of cancers.
Показать больше [+] Меньше [-]Overview of Traditional and Environmental Factors Related to Bone Health Полный текст
2022
Rubio-Gutierrez, Juan Carlos | Mendez-Hernández, Pablo | Guéguen, Yann | Galichon, Pierre | Tamayo-Ortiz, Marcela | Haupt, Karsten | Medeiros, Mara | Barbier, Olivier Christophe
Bone mass in adulthood depends on growth and mineralization acquired during childhood and adolescence. It is well known that these stages of life are crucial for bone development, where genetic, nutritional, hormonal, and lifestyle factors play a significant role. Bone loss is normally a natural and slow process that begins years later after the peak bone mass is achieved and continues throughout the lifespan. Lifestyle choices in childhood and adolescence such as minimal physical activity, excessive caffeine or carbonated beverages intake, malnutrition, cigarette use, or high alcohol consumption and other factors like environmental pollutants can also negatively affect bone health and accelerate the bone loss process. The aim of this work is an overview of risk factors associated with inadequate bone health in early life.
Показать больше [+] Меньше [-]Trace and rare earth element bioaccumulation in the spotted dogfish (Scyliorhinus stellaris) Полный текст
2022
Squadrone, Stefania | Biancani, Barbara | Da Rugna, Cristiano | Favaro, Livio | Pederiva, Sabina | Abete, Maria Cesarina
Metals (trace elements and rare earth elements, REEs) were analysed by inductively coupled plasma-mass spectrometry in blood, the liver, the kidney and muscle of ex situ spotted dogfish (Scyliorhinus stellaris). The controlled environment in which these elasmobranchs were hosted allowed to assess a baseline level of metals in the different organs since exposure via water and food can be easily monitored. The highest arsenic, chromium, copper, and iron values were found in the liver, cobalt in the kidney, and cadmium and rubidium in muscle. The highest total trace elements content was found in the trend liver (75 mg kg⁻¹) > blood (33 mg kg⁻¹) > muscle (31 mg kg⁻¹) > kidney (10 mg kg⁻¹), while the ΣREEs was the liver (30 μg kg⁻¹) > muscle (15 μg kg⁻¹) > kidney (13 μg kg⁻¹) > blood (4.1 μg kg⁻¹). Between REEs, the most represented element was scandium. Significant differences in the concentration of metals among organs were observed for almost all elements. Nonessential elements were generally lower and essential elements higher in the examined specimens compared to wild elasmobranchs, suggesting a close relationship between a balanced diet and animal welfare.
Показать больше [+] Меньше [-]SARS-COV-2/COVID-19: scenario, epidemiology, adaptive mutations, and environmental factors Полный текст
2022
Asghar, Asma | Imran, Hafiz Muhammad | Bano, Naheed | Maalik, Sadia | Mushtaq, Sajida | Hussain, Asim | Varjani, Sunita | Aleya, Lotfi | Iqbal, Hafiz M. N. | Vēlāyutan̲, T. A.
The coronavirus pandemic of 2019 has already exerted an enormous impact. For over a year, the worldwide pandemic has ravaged the whole globe, with approximately 250 million verified human infection cases and a mortality rate surpassing 4 million. While the genetic makeup of the related pathogen (SARS-CoV-2) was identified, many unknown facets remain a mystery, comprising the virus’s origin and evolutionary trend. There were many rumors that SARS-CoV-2 was human-borne and its evolution was predicted many years ago, but scientific investigation proved them wrong and concluded that bats might be the origin of SARS-CoV-2 and pangolins act as intermediary species to transmit the virus from bats to humans. Airborne droplets were found to be the leading cause of human-to-human transmission of this virus, but later studies showed that contaminated surfaces and other environmental factors are also involved in its transmission. The evolution of different SARS-CoV-2 variants worsens the condition and has become a challenge to overcome this pandemic. The emergence of COVID-19 is still a mystery, and scientists are unable to explain the exact origin of SARS-CoV-2. This review sheds light on the possible origin of SARS-CoV-2, its transmission, and the key factors that worsen the situation.
Показать больше [+] Меньше [-]Impact of government policies on photovoltaic supply chain considering quality in the power distribution system: a case study Полный текст
2022
Matinfard, Sahar | Yaghoubi, Saeed | Kharaji Manouchehrabadi, Maedeh
Nowadays, due to the lack of energy and the harmful effects of fossil fuels on the environment, many countries seek to use renewable sources such as solar energy, a clean and free energy source. Direct conversion of solar energy into electricity is the reason for using solar cells. This paper proposes a three-echelon photovoltaic supply chain with two suppliers (domestic and foreign), two power plants (big and small), and a power distribution system with government intervention. We consider three approaches, including (1) the decentralized model, (2) the centralized model, and (3) the government’s role in the photovoltaic supply chain. In the first model, the power distribution system is a leader, and other members are followers. In the second model, we explore the whole supply chain as a centralized model, and in the third model, the government has the leading role, and the rest of the members follow. Indeed, in the last model, the role of the government as a supporter that gives subsidies and tax exemptions to keep members in a competitive market is investigated, and the decision variables of the government (tariffs) are obtained. Finally, based on real example from the power industry of Iran, sensitivity analysis and managerial insights are proposed.
Показать больше [+] Меньше [-]Tap Water Quality Degradation in an Intermittent Water Supply Area Полный текст
2022
Shakya, Bijay Man | Nakamura, Takashi | Shrestha, Sadhana | Pathak, Sarad | Nishida, Kei | Malla, Rabin
Decentralized tap water systems are an important drinking water source worldwide. A good quality, high-pressure continuous water supply (CWS) is always the target of any urban settlement. However, tap water in some areas are reported with deteriorated water quality even though treated well before supplying. Such deterioration of tap water quality is reported widely from areas with low water availability and in economically poor countries where water are supplied intermittently (IWS). This study focuses in identifying tap water quality in IWS and causes of water quality degradation using nitrate-nitrogen (NO₃-N) as an indicator and stable isotopes of hydrogen (δD) as tracer. Nine water reservoirs and ninety municipal tap water (ten per reservoir) samples were collected during the wet (June–September) and dry (November–February) seasons in the Kathmandu Valley (KV), Nepal. Ten percent of the tap water samples exhibited higher NO₃-N than those of their respective reservoirs during the wet season, while 16% exhibited higher concentrations during the dry season. Similarly, the isotopic signatures of tap water exhibited 3% and 23% higher concentrations than those of their respective reservoirs during the wet and dry seasons, respectively. Coupling analysis between NO₃-N and δD demonstrates close connection of groundwater and tap water. The results indicate groundwater intrusion as the primary component in controlling tap water quality variations within the same distribution networks during IWS. Meanwhile, the obtained results also indicate probable areas of intrusion in the KV as well as usefulness of δD as a tool in the assessment of tap water systems.
Показать больше [+] Меньше [-]Peroxymonosulfate activation using heterogeneous catalyst Sr2FeO4 coated on SBA-15 for efficient degradation of antibiotic sulfapyridine Полный текст
2022
Zhao, Zheng-Yin | Xiong, Jun | Wang, Yuan | Cui, Caixi
It is significant to explore the advanced oxidation process (AOP) for antibiotic degradation. Herein, a peroxymonosulfate (PMS) activator, Sr₂FeO₄/SBA-15 (SFS) heterogeneous catalyst, was synthesized by in situ growth of Sr₂FeO₄ on the surface of SBA-15. In SFS/PMS catalytic system, Sr atom provided electrons to Fe(II) ↔Fe(III) ↔Fe(II) redox cycle through Sr-O-Fe bonds for PMS activation. The SFS catalyst could activate PMS to generate a free radical coexistence system, including sulfate radical (SO₄∙⁻) and hydroxyl radicals (∙OH). The catalyst possessed high catalytic activity and high stability. The degradation efficiency of sulfapyridine (SAD) over the SFS/PMS catalytic system could reach 99.0% after 90 min reaction. After the 5th reuse, the degradation efficiency of SAD was still more than 94.0%, and the phase structure of the catalyst did not alter. The low ion leaching concentration would be more conducive to reuse and avoiding secondary pollution, in comparison to homogeneous catalysts. This catalyst can be widely applied to organic wastewater treatment.-->
Показать больше [+] Меньше [-]Effects of chiral herbicide dichlorprop on Arabidopsis thaliana metabolic profile and its implications for microbial communities in the phyllosphere Полный текст
2022
Qiu, Danyan | Ye, Yizhi | Ke, Mingjing | Xu, Nuohan | Zhang, Zhenyan | Zhang, Fan | Kang, Jian | Yu, Yitian | Lu, Tao | Qian, Haifeng
Dichlorprop (2-(2,4-dichlorophenoxy) propionic acid, DCPP), a commonly used herbicide for weed control, can be residually detected in soil. It is still unclear whether chiral DCPP exerts an enantioselective adverse effect on plant metabolism and the microbial community of the phyllosphere. In this study, we selected Arabidopsis thaliana as a model plant to explore the effects of R- and S-DCPP enantiomers on plant physiological activities, metabolism, and associated changes in the phyllosphere microbial community. Results indicated that the fresh weight of plants decreased by 37.6% after R-DCPP treatment, whereas it increased by 7.6% after S-DCPP treatment. The R-DCPP enantiomer also caused stronger disturbance to leaf morphology, mesophyll cell structure, and leaf metabolites compared with S-DCPP. GC–MS analysis of DCPP-treated Arabidopsis leaves pointed out a differential profile mostly in carbohydrates, organic acids, and fatty acids, between S-DCPP and R-DCPP treatments. The diversity of phyllospheric microorganisms decreased and the stability of microbial community in the phyllosphere increased after R-DCPP treatment, whereas the opposite result was detected after S-DCPP exposure. The correlation analysis revealed that chiral herbicides may affect microbial communities in the phyllosphere by influencing leaf metabolism, while sugars and terpenoids were considered the main factors in reshaping the microbial community structure in the phyllosphere. Our study provides a new perspective for evaluating the effect of residual DCPP enantiomers on plant physiology and corresponding phyllosphere microorganism changes via the regulation of leaf metabolism, and clarifies the ecological risk of DCPP enantiomer application in agriculture.
Показать больше [+] Меньше [-]Synthesis, characterization, and dye degradation photocatalytic activity of the nano-size copper iron binary oxide Полный текст
2022
Mirzaei, Mahsa | Habibi, Mohammad Hossein | Sabzyan, Hassan
Magnetic nano-size copper iron binary oxide is synthesized via a sol–gel method using copper and iron nitrates as precursors and citric acid, chicken egg white, and starch as stabilizers followed by annealing at 400 °C and 800 °C in air. The TG-DTG, XRD, FESEM, EDX, VSM, and FT-IR and UV–Vis DRS spectroscopy methods are used for thermal, structural, magnetic, and optoelectronic characterizations. Depending on the stabilizer and annealing temperature, pure CuFe₂O₄, (CuFe₂O₄,CuO) or (CuFe₂O₄,CuO,Fe₂O₃) phases are formed with nano-size particles of 20–65 nm, having optical band gaps in the range of 2.15–2.60 eV (577–477 nm). Photocatalytic activities of the synthesized nano-size copper iron binary oxide samples are examined for degradation of Nile Blue textile dye displayed first-cycle removal (from water solution) efficiencies of 86.7–93.3%. Considering usage of non-toxic metals and low-cost green stabilizers, good degradation performances, and easy/efficient (magnetic) recyclability, this nano-size catalyst is suggested for further optimization studies for industrial applications.
Показать больше [+] Меньше [-]Physico-chemical characteristics of pulverized coals and their interrelations—a spontaneous combustion and explosion perspective Полный текст
2022
Mishra, Devi Prasad
Characteristics of pulverized coals have significant influence on the spontaneous combustion and explosion processes. This paper presents an experimental and theoretical framework on physico-chemical characteristics of coal and their interrelations from spontaneous combustion and explosion perspectives. The chemical properties, morphology, bulk density, particle size, and specific surface area of pulverized coals from nine different coal subsidiaries of India are vividly investigated in five distinct sizes. Moreover, the effects of particle size on bulk density, specific surface area, and N₂ adsorption capacity of pulverized coals are critically analyzed. With decrease in particle size, the bulk density of pulverized coals decreased, and the specific surface area and N₂ adsorption capacity increased. The relationships of bulk density and specific surface area of pulverized coals with particle size are established. Moreover, the specific surface areas determined by both the particle sizing and BET methods are compared, and correlation factors between them are determined. This study generated insightful coal characteristic data, which can be useful for furthering research on spontaneous combustion and explosion involving pulverized coals.
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