Mechanism Of Products Research Articles

Natural Products in the Treatment of Retinopathy of Prematurity: Exploring Therapeutic Potentials.

Retinopathy of prematurity (ROP) is a vascular disorder affecting the retinas of preterm infants. This condition arises when preterm infants in incubators are exposed to high oxygen levels, leading to oxidative stress, inflammatory responses, and a downregulation of vascular endothelial growth factors, which causes the loss of retinal microvascular capillaries. Upon returning to room air, the upregulation of vascular growth factors results in abnormal vascular growth of retinal endothelial cells. Without appropriate intervention, ROP can progress to blindness. The prevalence of ROP has risen, making it a significant cause of childhood blindness. Current treatments, such as laser therapy and various pharmacologic approaches, are limited by their potential for severe adverse effects. Therefore, a deeper understanding of ROP's pathophysiology and the development of innovative treatments are imperative. Natural products from plants, fungi, bacteria, and marine organisms have shown promise in treating various diseases and have gained attention in ROP research due to their minimal side effects and wide-ranging beneficial properties. This review discusses the roles and mechanisms of natural products that hold potential as therapeutic agents in ROP management.

Mechanism, Formulation, and Efficacy Evaluation of Natural Products for Skin Pigmentation Treatment.

Skin pigmentation typically arises from the excessive secretion and accumulation of melanin, resulting in a darker complexion compared to normal skin. Currently, the local application of chemical drugs is a first-line strategy for pigmentation disorders, but the safety and efficacy of drugs still cannot meet clinical treatment needs. For long-term and safe medication, researchers have paid attention to natural products with higher biocompatibility. This article begins by examining the pathogenesis and treatment approaches of skin pigmentation diseases and summarizes the research progress and mechanism of natural products with lightening or whitening effects that are clinically common or experimentally proven. Moreover, we outline the novel formulations of natural products in treating pigmentation disorders, including liposomes, nanoparticles, microemulsions, microneedles, and tocosomes. Finally, the pharmacodynamic evaluation methods in the study of pigmentation disorder were first systematically analyzed. In brief, this review aims to collect natural products for skin pigmentation treatment and investigate their formulation design and efficacy evaluation to provide insights for the development of new products for this complex skin disease.

Antifungal Mechanism of Natural Products Derived from Plants: A Review

Fungal resistance to the limited existing antifungal agents has become a considerable public health problem in the past few decades. However, natural products with multiple bioactivities are important sources for developing new therapeutic agents against fungi. Consequently, there is an urgent need to grasp the antifungal mechanism of natural products. In this review, the primary antifungal mechanisms of natural products derived from plants, including targeting the cell wall, cell membrane, mitochondria, biofilm and other mechanisms, are elaborated. This article critically describes the compounds with high antifungal activity, revealing opportunities for future research such as clinical trials or utilization as environmental disinfectants.

I2/CAN as an efficient reagent for the direct oxidation of tertiary Csp3-H to Csp3-OH: Synthesis of bis(N-methyl-7-azaindol-3-yl) (phenyl) methanol from 3,3′-(phenyl methylene)-bis(N-methyl-7-azaindole)

I2/CAN has emerged as a powerful and efficient oxidizing agent for direct tertiary CH oxidation of 3,3′-(phenyl methylene) bis(N-methyl-7-azaindole) under mild conditions to form bis(N-methyl-7-azaindol-3-yl) (phenyl)methanol in quantitative yield. Further, based on control experiments, a plausible mechanism and characterization of products including XRD are described. Synthetic transformation for bis(N-methyl-7-azaindol-3-yl) (phenyl) methanol is achieved by thionation.

Interaction mechanism of products from sulfidation roasting of nickel oxide with flotation reagents

Interaction mechanism of products from sulfidation roasting of nickel oxide with flotation reagents

Content Promotion and Community Experience: Marketing Mechanisms and Paths for Outdoor Sports Products--The Case of Arc'teryx

In the post epidemic period, outdoor sports have become a new trend in sports, and the demand for outdoor sports products has also increased. Among the many outdoor sports brands, Arc'teryx stands out and becomes the new favourite of people who love outdoor sports. So how did Arc'teryx become a big hit in the highly competitive outdoor sports market, with sales rising year after year? Currently, there are few detailed analyses of the brand's marketing mechanism and path. Therefore, the theme of this paper is the marketing mechanism and path of outdoor sports products--Taking Arc'teryx as an example. The research method is mainly case study method, mainly focusing on content marketing, analysing how the brand attracts audiences and builds communities through content marketing. The study found that Arc'teryx content marketing helped its own positioning and accurately attracted target customers, and the community experience also strengthened the brand's connection with customers. However, there are also shortcomings: the brand has fewer offline shops nationwide than other outdoor brands, and not all of them have a unique environment like the first shop in Shanghai to attract customers to buy. Arc'teryx still needs to revise its marketing strategy when the outdoor trend goes out of fashion to ensure that sales continue to grow, attract more people to participate in outdoor activities, and also maintain the vitality of the community and its appeal to the outside world. However, there's no denying that other outdoor sports brands can learn from Arc'teryxs marketing.

The Influence of Groundwater Migration on Organic Matter Degradation and Biological Gas Production in the Central Depression of Qaidam Basin, China

For insight into the productive and storage mechanisms of biogas in the Qaidam Basin, efforts were made to investigate the groundwater recharge and the processes of hydrocarbon generation by CDOM-EEM (fluorescence excitation-emission matrix of Chromophoric dissolved organic matter) spectrum, hydrogen and oxygen isotopes, and geochemical characters in the central depression of the Qaidam Basin, China. The samples contain formation water from three gas fields (TN, SB, and YH) and surrounding surface water (fresh river and brine lake). The results indicate that modern precipitation significantly controls the salinity distribution and organic matter leaching in the groundwater system of the central depression of the Qaidam Basin. Higher salinity levels inhibit microbial activity, which leads to organic matter degradation and to gas generation efficiency being limited in the groundwater. The inhabitation effect is demonstrated by the notable negative correlation between the extent of organic matter degradation and its concentration with hydrogen and oxygen isotopes. The conclusion of this study indicated that modern precipitation emerges as a crucial factor affecting the biogas production and storage in the Qaidam Basin by influencing the ultimate salinity and organic matter concentration in the formation, which provides theoretical insight for the maintenance of modern gas production wells and the assessment of gas production potential.

Ex-situ catalytic fast pyrolysis of waste polycarbonate for aromatic hydrocarbons: Utilizing HZSM-5/modified HZSM-5

Catalytic pyrolysis has been proven as a highly efficient process for transforming waste polycarbonate (PC) into valuable aromatic hydrocarbons, especially benzene, toluene, ethylbenzene, and xylene (BTEX). In the present work, the ex-situ catalytic fast pyrolysis of PC on metal- or alkali-modified HZSM-5 was investigated using the double micro-fixed bed system. Experimental results indicate that the rapid pyrolysis of PC may follow a homolytic chain scission mechanism, resulting in pyrolysis products dominated by phenols. Metal- or alkali-modified HZSM-5 significantly enhances the cleavage of C-OH bonds in phenols, improving the yield of aromatics. The yield of aromatics in the liquid product is 91 %, 72 %, and 77 % when loaded with nickel (Ni), iron (Fe), and cobalt (Co), respectively, all of which are higher than unmodified HZSM-5 with the yield of 43 %. Among them, the Ni/HZSM-5 has significantly enhanced the yield of BTEX reaching 81.64 %. When using alkali-modified HZSM-5 with a larger pore volume and higher specific surface area, the yield of aromatics can be increased to 60 %. Furthermore, the dual modification of alkali treatment and Ni loading on HZSM-5 simultaneously enhanced catalytic activity and resistance to coke formation. The yield of BTEX reaches 94.47 %. The BTEX formation mechanism can be explained by direct deoxygenation (DDO) of the pyrolytic volatiles of PC and the “phenol pool” mechanisms of primary products on the catalyst surface. This study enriches the understanding of catalytic pyrolysis of PC and provides a theoretical foundation for the harmless treatment of PC.

Response mechanism of ecosystem gross primary productivity to cloud and aerosol changes in a Chinese winter-wheat cropland.

Changes in clouds and aerosols may alter the quantity of solar radiance and its diffuse components, as well as air temperature (Ta) and vapor pressure deficit (VPD), thereby affecting canopy photosynthesis. Our aim was to determine how ecosystem gross primary productivity (GPP) responds to the cloudiness and aerosol depth changes, as indicated by diffuse light fraction (fDIF). The environmental factors that caused these responses were examined using 2 years of eddy covariance data from a winter-wheat cropland in northern China. The GPP decreased significantly along with the fDIF in a nonlinear pattern, with a determination coefficient of 0.91. Changes in fDIF altered total photosynthetic active radiation (PAR), diffuse PAR, Ta and VPD. The variations in GPP with fDIF in both fDIF change Phase I (fDIF < 0.65) and Phase II (fDIF > 0.65) resulted from the combined effects of multiple environmental factors. Because the driving factors were closely correlated, a path analysis was used to distinguish their respective contribution to the GPP response to fDIF by integrating path coefficients. In Phases I and II, the decreased responses of GPP to fDIF were mainly caused by total PAR and diffuse PAR, respectively, which contributed approximately 49% and 37% to GPP variations, respectively. Our research has certain implications for the necessity to consider fDIF and to incorporate diffuse light into photosynthetic models.

Theoretical study of the reaction of organic peroxyl radicals with alkenes and their accretion products involved in the atmospheric nucleation

Organic peroxy radicals, including alkyl peroxy radicals (RO2) and acyl peroxy radicals (RC(O)O2), are crucial intermediates in the atmospheric photochemical reactions of volatile organic compounds and directly or indirectly affect the distribution of other species (e.g., HO2 radicals, NOx, OH radicals, and alkenes). However, the atmospheric reactions of organic peroxyl radicals with alkenes (RO2 + alkene reactions) are not fully understood. The present study used theoretical calculations to investigate the reaction mechanisms of various organic peroxy radicals with different alkenes, with the aim of clarifying the influence of molecular structure on RO2 + alkene and RC(O)O2 + alkene reactions. Furthermore, we investigated the nucleation mechanisms of the subsequent oxidation products. The results show that the reaction rate constants for RC(O)O2 + alkene reactions are 1–6 orders of magnitude higher than those for RO2 + alkene reactions. The addition products formed by organic peroxy radicals with alkenes not only undergo monomolecular reactions to generate epoxides, but also participate in O2 addition to yield the accretion products ROOR’. H2SO4 molecules synergistically interact with low-volatility ROOR’ to grow clusters up to the 1–2 nm scale, and the ROOR’ molecules can form pure organic clusters larger than 1 nm, even in the absence of H2SO4 molecules. Our study provides a new perspective on the formation of accretion products in the atmosphere and their involvement in new particle formation.

An experimental and mechanism study on the pyrolysis of sulfur mustard

Experimental studies on the pyrolysis of sulfur mustard (HD) were conducted from 673 to 1473 K using Py-GC/MS combined with two separate columns. The HD pyrolysis rate exceeded 99 % at a pyrolysis time of approximately 2 seconds above 1073 K. The pyrolysis products of HD mainly include ethylene, vinyl chloride, carbon disulfide, thiophene, hydrogen chloride and hydrogen sulfide. The main reaction mechanism of HD pyrolysis was investigated using quantum chemistry methods combined with the TST/VTST theory. At 673 K, the initial reaction pathway of HD primarily involves an intramolecular HCl elimination and the cleavage of the C-S bond. The radical reactions will dominate the pyrolysis of HD once radical pool is formed. The reaction pathways of the important radical intermediates were analyzed, and the formation mechanisms of the main pyrolysis products were investigated. Theoretically, the high-pressure limit rate constants for the major reactions were calculated. This study contributes to a deeper understanding of the HD pyrolysis mechanism and provides a theoretical and data foundation for the destruction of HD.

The cellular and molecular targets of natural products against metabolic disorders: a translational approach to reach the bedside.

Metabolic disorders, including obesity, dyslipidemia, diabetes, nonalcoholic fatty liver disease, and metabolic syndrome, are characterized by insulin resistance, abnormalities in circulating cholesterol and lipid profiles, and hypertension. The most common pathophysiologies of metabolic disorders are glucose/lipid metabolism dysregulation, insulin resistance, inflammatory response, and oxidative stress. Although several agents have been approved for the treatment of metabolic disorders, there is still a strong demand for more efficacious drugs with less side effects. Natural products have been critical sources of drug research and discovery for decades. However, the usefulness of bioactive natural products is often limited by incomplete understanding of their direct cellular targets. In this review, we highlight the current understanding of the established and emerging molecular mechanisms of metabolic disorders. We further summarize the therapeutic effects and underlying mechanisms of natural products on metabolic disorders, with highlights on their direct cellular targets, which are mainly implicated in the regulation of glucose/lipid metabolism, insulin resistance, metabolic inflammation, and oxidative stress. Finally, this review also covers the clinical studies of natural products in metabolic disorders. These progresses are expected to facilitate the application of these natural products and their derivatives in the development of novel drugs against metabolic disorders.

Targeting dysregulated intracellular immunometabolism within synovial microenvironment in rheumatoid arthritis with natural products.

Immunometabolism has been an emerging hotspot in the fields of tumors, obesity, and atherosclerosis in recent decades, yet few studies have investigated its connection with rheumatoid arthritis (RA). In principle, intracellular metabolic pathways upstream regulated by nutrients and growth factors control the effector functions of immune cells. Dynamic communication and hypermetabolic lesions of immune cells within the inflammatory synovial microenvironment contributes to the development and progression of RA. Hence, targeting metabolic pathways within immune subpopulations and pathological cells may represent novel therapeutic strategies for RA. Natural products constitute a great potential treasury for the research and development of novel drugs targeting RA. Here, we aimed to delineate an atlas of glycolysis, lipid metabolism, amino acid biosynthesis, and nucleotide metabolism in the synovial microenvironment of RA that affect the pathological processes of synovial cells. Meanwhile, therapeutic potentials and pharmacological mechanisms of natural products that are demonstrated to inhibit related key enzymes in the metabolic pathways or reverse the metabolic microenvironment and communication signals were discussed and highlighted.

Structure-activity relationships, product species distribution and the mechanism of effect of multi-component flue gas on Hg0 adsorption and oxidation over CuO/ACs.

A series of Cu-doped activated cokes (CuO/ACs) were synthesized via an impregnation method and applied for the removal of elemental mercury (Hg0). Structure-activity relationships between Hg0 removal and CuO/AC surface characteristics were identified. Hg0 removal over CuO/AC occurs through a combination of physisorption and chemisorption and is mainly dominated by chemisorption. It was found that 1 nm micropores facilitate Hg0 physisorption. Hg0 could weakly adsorb onto an O-terminated crystal layer, whereas strongly adsorb onto Cu-terminated single highly dispersed, clustered and bulk CuO (110) crystal planes via the Mars-Maessen mechanism. Product distributions and mechanisms of Hg0 adsorption and oxidation over the CuO/AC catalyst under multi-component flue gases are also discussed. O2 enhances both physisorption and chemisorption toward Hg0 by 38%. Inhibition of Hg0 removal by SO2 originates from the competitive adsorption and deactivation of CuO cation vacancies, whereas the impact is weakened by O2 through generating 20% of physically adsorbed mercury product species. NO and O2 promote Hg0 chemisorption efficiency by 93% to form Hg(NO3)2. HOCl and/or Cl2 produced by HCl can oxidize 100% of Hg0 to HgCl2, and the catalytic oxidation efficiency is approximately 29%, but O2 slightly lowers the Hg0 catalytic oxidation efficiency by 8%. The affinity ability between various flue gases and Hg0 follows the order O2 < NO < HCl.

Commodity chain as a negotiated process: Empirical analysis of benefit allocation, governance, and powers of upstream and downstream actors in matsutake mushroom trade in Shangri-La, Yunnan Province

The commercialization of non-timber forest products beyond in-house consumption is a strategy for alleviating rural poverty and forest degradation. With the implementation of the ecological civilization program, the Chinese government has explored the value realization mechanism of sustainable ecological products, and many successful cases of agricultural product commercialization have emerged. Focusing on the matsutake of Shangri-La as an example, this study applies both qualitative and quantitative analysis of semi-structured interviews, participatory observation, secondary data collection, and statistical analysis for the dynamics of the matsutake commodity chain construction in the southwest plateau of China to obtain unique insights into contemporary rural China. Specifically, the interrelationships and functional logic of diverse participants in the core process of commodity management were analyzed. We found that the upstream and downstream participants in the matsutake commodity chain are subject to institutional constraints, such as land tenure and non-unified standards, and that markets are crucial to matsutake's trading in Shangri-La. Certain participants along the commodity chain have inefficient information sources, while middlemen have greater autonomy in the matsutake transaction process and a larger profit margin. Additionally, the involvement of the government and non-governmental organizations impacts the preservation of natural resources and the creation of a stable market order, but policies and funds tend to be short-lived. To improve the commodity chain sustainability of non-timber forest products in plateau areas, it is necessary to consider social and cultural factors, ensure the equity of different participants in the commodity chain, and protect traditional local knowledge related to natural resource management.

Effects of temperature fluctuations on the quality and microbial diversity of beef meatballs during simulated cold chain distribution.

Cold chain distribution with multiple links maintains low temperatures to ensure the quality of meat products, whereas temperature fluctuations during this are often disregarded by the industry. The present study simulated two distinct temperatures cold chain distribution processes. Quality indicators and high-throughput sequencing were employed to investigate the effects of temperature fluctuations on the quality and microbial diversity of beef meatballs during cold chain distribution. Quality indicators revealed that temperature fluctuations during simulated cold chain distribution significantly (P < 0.05) exacerbated the quality deterioration of beef meatballs. High-throughput sequencing demonstrated that temperature fluctuations affected the diversity and structure of microbial community. Lower microbial species abundance and higher microbial species diversity were observed in the temperature fluctuations group. Proteobacteria and Pseudomonas were identified as the dominant phylum and genus in beef meatballs, respectively, exhibiting faster growth rates and greater relative abundance under temperature fluctuations. The present study demonstrates that temperature fluctuations during simulated cold chain distribution can worsen spoilage and shorten the shelf life of beef meatballs. It also offers certain insights into the spoilage mechanism and preservation of meat products during cold chain distribution. © 2024 Society of Chemical Industry.

Natural Products with Potential Effects on Hemorrhoids: A Review.

Hemorrhoid disease is a common anorectal disorder affecting populations worldwide, with high prevalence, treatment difficulties, and considerable treatment costs. Compared to other treatment options, medical therapy for hemorrhoids offers minimal harm, more dignity to patients, and is more economical. Unfortunately, there are few chemical hemorrhoid medications available clinically, which makes the search for efficacious, cost-effective, and environmentally friendly new medication classes a focal point of research. In this context, searching for available natural products to improve hemorrhoids exhibits tremendous potential. These products are derived from nature, predominantly from plants, with a minor portion coming from animals, fungi, and algae. They have excellent coagulation pathway regulation, anti-inflammatory, antibacterial, and tissue regeneration activities. Therefore, we take the view that they are a class of potential hemorrhoid drugs, prevention products, and medication add-on ingredients. This article first reviews the factors contributing to the development of hemorrhoids, types, primary symptoms, and the mechanisms of natural products for hemorrhoids. Building on this foundation, we screened natural products with potential hemorrhoid improvement activity, including polyphenols and flavonoids, terpenes, polysaccharides, and other types.

Research on the mechanism of leader-follower product sales competition based on market access restrictions and forward contract considerations

Market access restrictions have been the focus of attention for various market players, but there are fewer studies on the competitive mechanism of market access restrictions on firms' product sales. This paper investigates the competitive mechanism of leader-follower product sales based on market access restrictions and forward contracts. First, the mechanism of leader-follower sales decisions based on market access restrictions and forward contracts is clarified. Second, it models the forward default risk suffered by followers and the profit rate of leader-follower based on market access restrictions and forward considerations by Bayes' posterior probability method. Moreover, it severely explores the impact mechanisms of the degree of market access restrictions on leaders and followers when followers do not adopt and adopt forwards and makes a simulation analysis. The results show that: (i) When followers do not employ forward contracts, the less restrictive degree of market access increases the supply of leaders, and leaders' competition for product sales further leads to a decrease in the provision of followers. (ii) When followers use forwards, leaders' and followers' expected discounted profit rates decrease with the total supply of products in the market increases. (iii) If the degree of market access restrictions is low, the followers suffer an increased forward default risk, resulting in their rate of revenue decrease. The findings of this paper have some practical significance and policy implications for the regulator to adjust the degree of market access restriction in each restricted access area, to establish a reasonable and efficient competitive environment for product sales, as well as for firms to choose the optimal way of competing for product sales.

Pinpointing the causal influences of stomatal anatomy and behavior on minimum, operational, and maximum leaf surface conductance.

Leaf surface conductance to water vapor and CO2 across the epidermis (gleaf) strongly determines the rates of gas exchange. Thus, clarifying the drivers of gleaf has important implications for resolving the mechanisms of photosynthetic productivity and leaf and plant responses and tolerance to drought. It is well recognized that gleaf is a function of the conductances of the stomata (gs) and of the epidermis + cuticle (gec). Yet, controversies have arisen around the relative roles of stomatal density (d) and size (s), fractional stomatal opening (α; aperture relative to maximum), and gec in determining gleaf. Resolving the importance of these drivers is critical across the range of leaf surface conductances, from strong stomatal closure under drought (gleaf,min), to typical opening for photosynthesis (gleaf,op), to maximum achievable opening (gleaf,max). We derived equations and analyzed a compiled database of published and measured data for approximately 200 species and genotypes. On average, within and across species, higher gleaf,min was determined 10 times more strongly by α and gec than by d and negligibly by s; higher gleaf,op was determined approximately equally by α (47%) and by stomatal anatomy (45% by d and 8% by s), and negligibly by gec; and higher gleaf,max was determined entirely by d. These findings clarify how diversity in stomatal functioning arises from multiple structural and physiological causes with importance shifting with context. The rising importance of d relative to α, from gleaf,min to gleaf,op, enables even species with low gleaf,min, which can retain leaves through drought, to possess high d and thereby achieve rapid gas exchange in periods of high water availability.

SPENT MEDIA ANALYSIS AIDS IN DETERMINING METABOLIC MECHANISMS OF SUPERIOR CAR T-CELL PRODUCTS

SPENT MEDIA ANALYSIS AIDS IN DETERMINING METABOLIC MECHANISMS OF SUPERIOR CAR T-CELL PRODUCTS