Oxidation reactions by radicals constitute a very important class of chemical reactions in solution. Radiation Chemistry methods allow producing, in a controlled way, very reactive oxidizing ...radicals, such as OH
, CO₃
, NO₃
, SO₄
, and N₃
. Although the radical cation of water, H₂O
, with a very short lifetime (shorter than 1 ps) is the precursor of these radicals in aqueous solutions, its chemistry is usually known to be limited to the reaction of proton transfer by forming OH
radical. Herein, we stress situations where H₂O
undergoes electron transfer reaction in competition with proton transfer.
• Anthocyanin and proanthocyanidin (PA) accumulation is regulated by both myeloblastosis (MYB) activators and repressors, but little information is available on hierarchical interactions between the ...positive and negative regulators. Here, we report on a R2R3-MYB repressor in peach, designated PpMYB18, which acts as a negative regulator of anthocyanin and PA accumulation.
• PpMYB18 can be activated by both anthocyanin- and PA-related MYB activators, and is expressed both at fruit ripening and juvenile stages when anthocyanins or PAs, respectively, are being synthesized.
• The PpMYB18 protein competes with MYB activators for binding to basic Helix Loop Helixes (bHLHs), which develops a fine-tuning regulatory loop to balance PA and anthocyanin accumulation. In addition, the bHLH binding motif in the R3 domain and the C1 and C2 repression motifs in the C-terminus of PpMYB18 both confer repressive activity of PpMYB18.
• Our study also demonstrates a modifying negative feedback loop, which prevents cells from excess accumulation of anthocyanin and PAs, and serves as a model for balancing secondary metabolite accumulation at the transcriptional level.
Plant roots and soil microorganisms interact with each other mainly in the rhizosphere. Changes in the community structure of the rhizosphere microbiome are influenced by many factors. In this study, ...we determined the community structure of rhizosphere bacteria in cotton, and studied the variation of rhizosphere bacterial community structure in different soil types and developmental stages using TM-1, an upland cotton cultivar (Gossypium hirsutum L.) and Hai 7124, a sea island cotton cultivar (G. barbadense L.) by high-throughput sequencing technology. Six bacterial phyla were found dominantly in cotton rhizosphere bacterial community including Acidobacteria, Actinobacteria, Bacteroidetes, Planctomycetes, Proteobacteria, and Verrucomicrobia. The abundance of Acidobacteria, Cyanobacteria, Firmicutes, Planctomycetes and Proteobacteria were largely influenced by cotton root. Bacterial α-diversity in rhizosphere was lower than that of bulk soil in nutrient-rich soil, but higher in cotton continuous cropping field soil. The β-diversity in nutrient-rich soil was greater than that in continuous cropping field soil. The community structure of the rhizosphere bacteria varied significantly during different developmental stages. Our results provided insights into the dynamics of cotton rhizosphere bacterial community and would facilitate to improve cotton growth and development through adjusting soil bacterial community structure artificially.
Diagenetic processes and associated pore evolution are essential factors that control the development and distribution of porosity and permeability in saline reservoirs. The goal of this study is to ...systematically describe the comparative diagenetic processes, porosity evolution, and diagenetic facies of sandstone reservoirs in the Eocene Lower Xingouzui Formation (LXF) in two depressions in the Jianghan Basin, China. To achieve these goals, an integrated approach of petrographic, mineralogical, geochemical, and petrophysical analyses such as thin-section observations, X-ray diffraction (XRD), and mercury intrusion porosimetry (MIP) was applied to sandstone samples obtained from the Qianjiang and Jiangling sags. Diagenetic studies showed that the LXF samples had experienced several phases of diagenesis, including compaction, non-ferroan carbonate/sulfate cementation, feldspar and carbonate dissolution, quartz overgrowth cementation, ferroan carbonate and sulfate cementation, cubic pyrite precipitation, and limited gypsum dissolution. Although the LXF samples from both the Qianjiang and Jiangling sags experienced a noticeable porosity reduction induced by the compaction, the differences in diagenesis between these two sags were primarily due to complex and diverse cementation types. For instance, both early carbonate and sulfate cementation were recognized in Qianjiang samples, while only early carbonate cements were present in Jiangling samples. Based on a quantitative evaluation of the relative importance of diagenetic processes, diagenetic facies were defined in the LXF sandstones. Additionally, the pore evolution study indicated that two (upper and lower) zones of abnormally high porosity and permeability (AHPP) were developed in both sags. In particular, the upper AHPP zones occurred in sandstones in the Qianjiang and Jiangling depressions at depths of 1300 and 1800 m, respectively, while the lower AHPP zones in both depressions were located at a depth of 3300 m. The differences in the development mechanisms between the upper and lower AHPP zones were determined. This work provides an overview of the evolution and evaluation of sulfate- and carbonate-bearing sandstone reservoirs, such as the LXF sandstone, which have experienced strong diagenetic modifications during their geological histories.
•Evaporite-related diagenesis variations between two depressions were studied and compared.•Compaction played a more significant role in porosity reduction than cementation.•Four diagenetic facies and three types of favorable reservoirs were defined in the Eocene Lower Xingouzui Formation.
Diabetic complications pose a significant threat to life and have a negative impact on quality of life in individuals with diabetes. Among the various factors contributing to the development of these ...complications, endothelial dysfunction plays a key role. The main mechanism underlying endothelial dysfunction in diabetes is oxidative stress, which adversely affects the production and availability of nitric oxide (NO). Flavonoids, a group of phenolic compounds found in vegetables, fruits, and fungi, exhibit strong antioxidant and anti-inflammatory properties. Several studies have provided evidence to suggest that flavonoids have a protective effect on diabetic complications. This review focuses on the imbalance between reactive oxygen species and the antioxidant system, as well as the changes in endothelial factors in diabetes. Furthermore, we summarize the protective mechanisms of flavonoids and their derivatives on endothelial dysfunction in diabetes by alleviating oxidative stress and modulating other signaling pathways. Although several studies underline the positive influence of flavonoids and their derivatives on endothelial dysfunction induced by oxidative stress in diabetes, numerous aspects still require clarification, such as optimal consumption levels, bioavailability, and side effects. Consequently, further investigations are necessary to enhance our understanding of the therapeutic potential of flavonoids and their derivatives in the treatment of diabetic complications.
Alzheimer's disease (AD), an age-dependent neurodegenerative disorder, is the most prevalent neurodegenerative disease worldwide. The primary pathological hallmarks of AD are the deposition of ...β-amyloid plaques and neurofibrillary tangles. Autophagy, a pathway of clearing damaged organelles, macromolecular aggregates, and long-lived proteins via lysosomal degradation, has emerged as critical for proteostasis in the central nervous system (CNS). Studies have demonstrated that defective autophagy is strongly implicated in AD pathogenesis. Transcription factor EB (TFEB), a master transcriptional regulator of autophagy, enhances the expression of related genes that control autophagosome formation, lysosome function, and autophagic flux. The study of TFEB has greatly increased over the last decade, and the dysfunction of TFEB has been reported to be strongly associated with the pathogenesis of many neurodegenerative disorders, including AD. Here, we delineate the basic understanding of TFEB dysregulation involved in AD pathogenesis, highlighting the existing work that has been conducted on TFEB-mediated autophagy in neurons and other nonneuronal cells in the CNS. Additionally, we summarize the small molecule compounds that target TFEB-regulated autophagy involved in AD therapy. Our review may yield new insights into therapeutic approaches by targeting TFEB and provide a broadly applicable basis for the clinical treatment of AD.
Antiretroviral chemoprophylaxis before exposure is a promising approach for the prevention of human immunodeficiency virus (HIV) acquisition.
We randomly assigned 2499 HIV-seronegative men or ...transgender women who have sex with men to receive a combination of two oral antiretroviral drugs, emtricitabine and tenofovir disoproxil fumarate (FTC-TDF), or placebo once daily. All subjects received HIV testing, risk-reduction counseling, condoms, and management of sexually transmitted infections.
The study subjects were followed for 3324 person-years (median, 1.2 years; maximum, 2.8 years). Of these subjects, 10 were found to have been infected with HIV at enrollment, and 100 became infected during follow-up (36 in the FTC-TDF group and 64 in the placebo group), indicating a 44% reduction in the incidence of HIV (95% confidence interval, 15 to 63; P=0.005). In the FTC-TDF group, the study drug was detected in 22 of 43 of seronegative subjects (51%) and in 3 of 34 HIV-infected subjects (9%) (P<0.001). Nausea was reported more frequently during the first 4 weeks in the FTC-TDF group than in the placebo group (P<0.001). The two groups had similar rates of serious adverse events (P=0.57).
Oral FTC-TDF provided protection against the acquisition of HIV infection among the subjects. Detectable blood levels strongly correlated with the prophylactic effect. (Funded by the National Institutes of Health and the Bill and Melinda Gates Foundation; ClinicalTrials.gov number, NCT00458393.).
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•Wheat and maize straw, wood branch and their briquettes and charcoals were tested.•EFs of OC were averagely 3.2 times higher than EC while K (K+) and Cl (Cl−) were comparable in ...PM2.5.•Levoglucosan dominated the total saccharides with EFs of 0.03–110.41 mg kg−1.•Charcoals showed over 90% emission reduction efficiency compared to raw fuels.
In this study, maize straw, wheat straw, and wood branches and their processed products (i.e., briquettes and charcoals) were used to investigate the emission factors (EFs) of PM2.5 components and the influence of form changing. The EFs of organic carbon (OC) was 241 ± 39.7 to 3920 ± 792 mg kg−1; OC was the largest contributor in PM2.5. The EFs of PM2.5, OC and elemental carbon (EC) demonstrated that charcoal was the most efficient in reducing PM2.5 and carbonaceous fraction emissions, followed by briquettes compared with raw fuels in residential burning use. Among cations, K+ had the highest EF, whereas Cl− has the highest EF among anions; the presence of both K+ and Cl− was attributable to high abundance in biomass. Cl, K, S, and Na (in descending order) contributed more than 95% of total elements with high EFs; the other elements, particularly heavy metals, had very low EFs. The EFs of total polycyclic aromatic hydrocarbons (PAHs) and saccharides were in the following order of magnitude: raw fuels > briquettes > charcoals. PAHs with four rings (i.e., pyrenes) dominated the total PAHs in PM2.5−, whereas among saccharides, levoglucosan had the largest EFs (0.03–110.41 mg kg−1). Briquettes, with simple process and reasonable cost, demonstrated a good ability in decreasing PM2.5 emission with potential of 53% (765,000–427,000 t year−1), and their emission reduction potential were much higher for straws than for branches. Charcoals demonstrated considerable emission reduction potential for straw (93.7% averagely for PM2.5 and compositions) and comparable for wood branches (80% averagely) while its complex process and high cost should be considered. More than 600,000 t of PM2.5 and thousands of tons of PAHs and saccharides are estimated to be eliminated annually if all raw biomass fuels are processed through carbonization. Considering the efficiency–cost ratios, biomass briquetting may aid clean heating in rural areas, in addition to the “natural gas and electricity replacement strategy,” in China and other countries facing similar problems.
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•Lindera aggregata can alleviate CKD by improving kidney pathology.•Lindera aggregata can alleviate CKD by regulating related biochemical indicators.•Lindera aggregata can alleviate ...CKD by regulating the metabolic profiling.•Lindera aggregata can regulate TGF-β/Smad signaling pathway.
Lindera aggregata is a main Chinese herb of ancient prescriptions Suoquan pill applied for treating the chronic kidney disease (CKD). A large number of application histories of Lindera aggregata in the treatment of CKD have been recorded in Chinese traditional medical literature. The previous reports revealed that Lindera aggregata can treat CKD.
Rats were randomly divided into control, model, Huangkui,Lindera aggregata ethanol extract (LEE) and Lindera aggregata water extract (LWE) groups. hematoxylin-eosin (HE) staining was used to detect the pathology of kidney. The levels of serum creatinine (Scr), serum Neutrophil gelatinase-associated lipocalin (NGAL), blood urea nitrogen (BUN), urine protein (UP), kidney index(KI) were evaluated. The UPLC − QTOF/MS were applied to probe the metabolic profile. Furthermore, Indoxyl sulfate-induced human renal tubular epithelial (HK-2) cell model was built to determine the expression levels of pathogenesis-related proteins.
The results demonstrated that LEE and LWE significantly inhibited the rebound in Scr, BUN, NGAL, UP and KI in models, except for the effect of LWE at low dose (LWE-L) and LEE at low dose (LEE-L) on KI and the effect of LWE-H at high dose (LWE-H) and LEE-L on BUN and NGAL. Moreover,Lindera aggregata extracts alleviated renal tubular dilatation, interstitial fibrosis and interstitial inflammation. By analysis, twenty-eight metabolites were related to CKD. After intervention of Lindera aggregata extracts, some metabolites approach to a normal-like level, such as Indoxyl sulfate. These metabolites are mainly involved in tryptophan, fatty acid, glycerophospholipid, tyrosine and arachidonic acid metabolic pathways. Furthermore, Lindera aggregata extracts mediate the expression of smad2, smad3, smad7 and TGF-β in Indoxyl sulfate-induced HK-2 cell.
Lindera aggregata extracts can mitigate adenine-induced CKD by modulating the metabolic profile and TGF-β/Smad signaling pathway, providing important supports for developing protective agent of Lindera aggregata for CKD.
Mitochondria maintain the normal physiological function of nerve cells by producing sufficient cellular energy and performing crucial roles in maintaining the metabolic balance through intracellular ...Ca2+ homeostasis, oxidative stress, and axonal development. Depression is a prevalent psychiatric disorder with an unclear pathophysiology. Damage to the hippocampal neurons is a key component of the plasticity regulation of synapses and plays a critical role in the mechanism of depression. There is evidence suggesting that mitochondrial dysfunction is associated with synaptic impairment. The maintenance of mitochondrial homeostasis includes quantitative maintenance and quality control of mitochondria. Mitochondrial biogenesis produces new and healthy mitochondria, and mitochondrial dynamics cooperates with mitophagy to remove damaged mitochondria. These processes maintain mitochondrial population stability and exert neuroprotective effects against early depression. In contrast, mitochondrial dysfunction is observed in various brain regions of patients with major depressive disorders. The accumulation of defective mitochondria accelerates cellular nerve dysfunction. In addition, impaired mitochondria aggravate alterations in the brain microenvironment, promoting neuroinflammation and energy depletion, thereby exacerbating the development of depression. This review summarizes the influence of mitochondrial dysfunction and the underlying molecular pathways on the pathogenesis of depression. Additionally, we discuss the maintenance of mitochondrial homeostasis as a potential therapeutic strategy for depression.
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•Mitochondrial dysfunction plays a vital role in the etiology of depression.•Dysregulation of the mitochondrial quality control system exacerbates the pathophysiology of depression.•Mitochondrial energy metabolism disorders fail to provide physiological support for neuroplasticity in depression.•The interaction between defective mitochondria and neuroinflammation worsens depression.•Mitochondria represent a potential target for pharmacological intervention of depression.
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