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1.
World J Clin Cases ; 12(21): 4742-4747, 2024 Jul 26.
Article in English | MEDLINE | ID: mdl-39070821

ABSTRACT

BACKGROUND: Primary hepatic lymphoma (PHL) is a lymphoproliferative disorder confined to the liver without peripheral lymph node involvement and bone marrow invasion. PHL is extremely rare in clinical practice. The etiology and pathogenesis of PHL are largely unknown. There are no common standard protocols or guidelines for the treatment of PHL. CASE SUMMARY: We report the case of a 66-year-old man who presented with fever and abdominal pain for three weeks. Computed tomography and magnetic resonance imaging scans showed a pyogenic liver abscess. The patient underwent a right posterior hepatectomy. The surgical pathology revealed aggressive B-cell lymphoma, with a primary consideration of diffuse large B-cell lymphoma of non-germinal center origin. CONCLUSION: This article reviews the characteristics, mechanism and treatment of PHL and provides insight into the diagnosis of PHL.

2.
Adv Respir Med ; 92(4): 263-277, 2024 Jul 20.
Article in English | MEDLINE | ID: mdl-39051188

ABSTRACT

A common life-threatening hereditary disease, Cystic Fibrosis (CF), affects primarily Caucasian infants. High sweat-salt levels are observed as a result of a single autosomal mutation in chromosome 7 that affects the critical function of the cystic fibrosis transmembrane regulator (CFTR). For establishing tailored treatment strategies, it is important to understand the broad range of CFTR mutations and their impacts on disease pathophysiology. This study thoroughly investigates the six main classes of classification of CFTR mutations based on their functional effects. Each class is distinguished by distinct molecular flaws, such as poor protein synthesis, misfolding, gating defects, conduction defects, and decreased CFTR expression at the apical membrane. Furthermore, this paper focuses on the emerging field of CFTR modulators, which intend to restore CFTR function or mitigate its consequences. These modulators, which are characterized by the mode of action and targeted mutation class, have the potential to provide personalized therapy regimens in CF patients. This review provides valuable insights into the genetic basis of CF pathology, and highlights the potential for precision medicine methods in CF therapy by thoroughly investigating CFTR mutation classification and related modulators.


Subject(s)
Cystic Fibrosis Transmembrane Conductance Regulator , Cystic Fibrosis , Mutation , Humans , Cystic Fibrosis/genetics , Cystic Fibrosis/therapy , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Precision Medicine/methods
3.
J Affect Disord ; 362: 661-669, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39019221

ABSTRACT

BACKGROUND: According to the healthy context paradox, the negative effects of peer victimization on core self-evaluation and depressive symptoms may vary in different levels of classroom-level victimization. However, previous studies have not investigated this issue using a longitudinal study design. OBJECTIVE: The present study used a longitudinal design to examine why and under what conditions peer victimization was associated with adolescents' depressive symptoms. METHOD: A large number of Chinese adolescents (Time 1: N = 4164, 50.3 % girls, Mage = 12.89, SDage = 0.77; Time 2: N = 4001, 50.4 % girls, Mage = 14.39, SDage = 0.75) were followed for one and a half years. RESULTS: Results showed that adolescents who were victimized in healthy contexts were more depressed and were at an increased risk of reporting more negative core self-evaluation than those victimized in unhealthy contexts. Moreover, core self-evaluation served as a mediator between peer victimization and depressive symptoms. LIMITATIONS: This study included two waves of data, which limited the exploration of dynamic relationships between peer victimization and depressive symptoms. In addition, the self-reported data weakened the objectivity of the results. Finally, this study neglected the effects of different dimensions of peer victimization on depressive symptoms. CONCLUSIONS: The healthy context paradox of peer victimization is identified in China, highlighting that future interventions of peer victimization should pay more attention to specific remaining victimized and self-devaluing individuals in healthy contexts.

4.
Ann Med Surg (Lond) ; 86(7): 4042-4048, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38989236

ABSTRACT

Osteoarthritis (OA) is a chronic disorder caused by degenerative changes in articular cartilage, which are mainly manifests as degeneration of cartilage, subchondral bone remodeling, as well as synovial inflammation. Over the next few decades, OA and its burden will continue to increase worldwide, posing a major public health challenge for the foreseeable future. Treatment for OA includes non-pharmacological, pharmacological, and surgical treatments. Existing conservative treatments and joint surgery can only alleviate the symptoms and cannot be cured, so new therapies for OA are urgently needed. Since advances in the understanding of OA pathophysiology, researchers have identified some potential therapeutic targets against degeneration of cartilage, subchondral bone remodeling and synovial inflammation, enabling development of the disease-modifying OA drugs (DMOADs). Additionally, a number of new technologies are also being investigated for treating OA, such as RNA interference (RNAi), CRISPR/Cas9 and PROTAC. The goal of this review is to describe the current development status of DMOADs and to discuss the potential of emerging therapeutic approaches for treating OA, thus providing a reference for OA treatments.

5.
Adv Mater ; : e2405718, 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-39014920

ABSTRACT

As-cast organic solar cells (OSCs) possess tremendous potential for low-cost commercial applications. Herein, five small-molecule acceptors (A1-A5) are designed and synthesized by selectively and elaborately extending the alkyl inner side chain flanking on the pyrrole motif to prepare efficient as-cast devices. As the extension of the alkyl chain, the absorption spectra of the films are gradually blue-shifted from A1 to A5 along with slightly uplifted lowest unoccupied molecular orbital energy levels, which is conducive for optimizing the trade-off between short-circuit current density and open-circuit voltage of the devices. Moreover, a longer alkyl chain improves compatibility between the acceptor and donor. The in situ technique clarifies that good compatibility will prolong molecular assembly time and assist in the preferential formation of the donor phase, where the acceptor precipitates in the framework formed by the donor. The corresponding film-formation dynamics facilitate the realization of favorable film morphology with a suitable fibrillar structure, molecular stacking, and vertical phase separation, resulting in an incremental fill factor from A1 to A5-based devices. Consequently, the A3-based as-cast OSCs achieve a top-ranked efficiency of 18.29%. This work proposes an ingenious strategy to manipulate intermolecular interactions and control the film-formation process for constructing high-performance as-cast devices.

6.
AMB Express ; 14(1): 84, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39043981

ABSTRACT

Cystic Fibrosis Transmembrane Regulator (CFTR) is a significant protein that is responsible for the movement of ions across cell membranes. The cystic fibrosis (CF) occur due to the mutations in the CFTR gene as it produces the dysfunctional CFTR protein. The sequence of CFTR protein as a target structure was retrieved from UniProt and PDB database. The ligands selection was performed through virtual screening and top 3 ligands choose out of 65 ligands silibinins, curcumin, demethoxycurcumin were selected with a reference drug Trikafta (R*). According to docking, ADMET analyses, the natural ligands (Silibinins and Curcumin) displayed best binding energy, pharmacokinetic and free toxicity than other natural compounds and reference drug (R*). An MD simulation for 200 ns was also established to ensure that natural ligands (Silibinins and Curcumin) attached to the target protein favorably and dynamically, and that protein-ligand complex stability was maintained. It is concluded that silibinins and curcumins have a better capacity to decrease the effect of mutant CFTR protein through improved trafficking and the restoration of original function. In conclusion, in silico studies demonstrate the potential of silibinins and curcumin as therapeutic agents for cystic fibrosis, particularly for the D614G mutated protein. Their ability to increase CFTR function while reducing cellular stress and inflammation, together with their favorable safety profile and accessibility could make them valuable additions to cystic fibrosis treatment options. Further experimental and clinical validation will be required to fully realize their potential and include them into effective therapy regimens.

7.
World J Clin Oncol ; 15(6): 765-782, 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38946828

ABSTRACT

BACKGROUND: Lung cancer bone metastasis (LCBM) is a disease with a poor prognosis, high risk and large patient population. Although considerable scientific output has accumulated on LCBM, problems have emerged, such as confusing research structures. AIM: To organize the research frontiers and body of knowledge of the studies on LCBM from the last 22 years according to their basic research and translation, clinical treatment, and clinical diagnosis to provide a reference for the development of new LCBM clinical and basic research. METHODS: We used tools, including R, VOSviewer and CiteSpace software, to measure and visualize the keywords and other metrics of 1903 articles from the Web of Science Core Collection. We also performed enrichment and protein-protein interaction analyses of gene expression datasets from LCBM cases worldwide. RESULTS: Research on LCBM has received extensive attention from scholars worldwide over the last 20 years. Targeted therapies and immunotherapies have evolved into the mainstream basic and clinical research directions. The basic aspects of drug resistance mechanisms and parathyroid hormone-related protein may provide new ideas for mechanistic study and improvements in LCBM prognosis. The produced molecular map showed that ribosomes and focal adhesion are possible pathways that promote LCBM occurrence. CONCLUSION: Novel therapies for LCBM face animal testing and drug resistance issues. Future focus should centre on advancing clinical therapies and researching drug resistance mechanisms and ribosome-related pathways.

8.
Article in English | MEDLINE | ID: mdl-39001887

ABSTRACT

PURPOSE: Negative life events are essential proximal factors that may induce suicidal behavior in adolescents, but the mechanisms connecting this link remain to further explored. The present study aimed to investigate the relationship between negative life events (NLEs) and adolescents' suicidal behavior, and the roles of core self-evaluation, depression and gender playing between them. METHODS: Using the whole-group sampling approach, 5296 Chinese adolescents (51.5% males, Meanage = 12.93) took part in this cross-sectional study in September 2021 and completed a battery of surveys including NLEs, suicidal behavior, CSE (core self-evaluation) and depression. Logistic regression and latent structural equation models were used to test the direct and indirect effects between NLEs and suicide behavior with multi-group path analysis, gender differences in this serial mediating effect were also tested. RESULTS: After controlling for age and gender, NLEs were directly associated with adolescents' suicidal behavior. CSE and depression played significant serial mediating effects in this relationship. Moreover, significant gender differences were obtained in these serial mediating pathways, with stronger effects in girls. CONCLUSION: Integrating the environmental, individual cognitive and emotional factors, our findings would be helpful in understanding the mechanism of these antecedents on adolescents' suicide behavior, which has specific practical significance for preventing and reducing suicidal behavior.

9.
J Natl Cancer Inst ; 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38833681

ABSTRACT

BACKGROUND: Despite the wide use of a three-month gonadotropin-releasing hormone agonist (3M GnRHa) for ovarian function suppression (OFS) in premenopausal breast cancer patients, it remains unclear whether it is as effective and safe as a one-month GnRHa regimen (1M GnRHa) when combined with selective estrogen receptor modulators (SERMs) or aromatase inhibitors (AIs), especially in younger patients. METHODS: This retrospective cohort study included 1109 premenopausal hormone receptor-positive (HR+) breast cancer patients treated with GnRHa plus SERM or AI. The estradiol (E2) inhibition rate within 1-24 months after treatment with 1M or 3M GnRHa in cohorts and different subgroups was analyzed. RESULTS: Following 1:1 propensity score matching, 950 patients with a mean age of 39 years and a median follow-up of 46 months were included. Both the 1M and 3M groups achieved >90% E2 inhibition within 24 months (94.53% vs 92.84%, 95% CI (-4.78%, 1.41%)), confirming the non-inferiority of 3M GnRHa. Both 1M and 3M GnRHa rapidly and consistently reduced E2 levels. 60 (6.3%) patients experienced incomplete ovarian function suppression (iOFS), with similar rates in the 1M and 3M groups (5.5% vs 7.2%). iOFS mainly occurred within the first 12 months, with age <40 years and no prior chemotherapy being the risk factors. Similar disease-free survival (DFS) and overall survival (OS) were found in the 1M and 3M groups, and in patients with complete and incomplete OFS (p > .05). CONCLUSIONS: The OFS with 3M GnRHa was not inferior to that with 1M GnRHa, regardless of age or combination with a SERM or an AI.

10.
Article in English | MEDLINE | ID: mdl-38896210

ABSTRACT

BACKGROUND: The associations between mood disorders (anxiety and depression) and mild cognitive impairment (MCI) or Alzheimer's dementia (AD) remain unclear. METHODS: Data from the Australian Imaging, Biomarker & Lifestyle (AIBL) study were subjected to logistic regression to determine both cross-sectional and longitudinal associations between anxiety/depression and MCI/AD. Effect modification by selected covariates was analysed using the likelihood ratio test. RESULTS: Cross-sectional analysis was performed to explore the association between anxiety/depression and MCI/AD among 2,209 participants with a mean [SD] age of 72.3 [7.4] years, of whom 55.4% were female. After adjusting for confounding variables, we found a significant increase in the odds of AD among participants with two mood disorders (anxiety: OR 1.65 [95% CI 1.04-2.60]; depression: OR 1.73 [1.12-2.69]). Longitudinal analysis was conducted to explore the target associations among 1,379 participants with a mean age of 71.2 [6.6] years, of whom 56.3% were female. During a mean follow-up of 5.0 [4.2] years, 163 participants who developed MCI/AD (refer to as PRO) were identified. Only anxiety was associated with higher odds of PRO after adjusting for covariates (OR 1.56 [1.03-2.39]). However, after additional adjustment for depression, the association became insignificant. Additionally, age, sex, and marital status were identified as effect modifiers for the target associations. CONCLUSION: Our study provides supportive evidence that anxiety and depression impact on the evolution of MCI/AD, which provides valuable epidemiological insights that can inform clinical practice, guiding clinicians in offering targeted dementia prevention and surveillance programs to the at-risk populations.

11.
Nat Commun ; 15(1): 4908, 2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38851721

ABSTRACT

C - N axially chiral compounds have recently attracted significant interest among synthetic chemistry community due to their widespread application in pharmaceuticals, advanced materials and organic synthesis. Although the emerging asymmetric Catellani reaction offers great opportunity for their modular and efficient preparation, the only operative chiral NBE strategy to date requires using half stoichiometric amount of chiral NBE and 2,6-disubstituted bromoarenes as electrophiles. We herein report an efficient assembly of C-N axially chiral scaffolds through a distinct chiral ligand strategy. The crucial chiral source, a biimidazoline (BiIM) chiral dinitrogen ligand, is used in relatively low loading and permits the use of less bulky bromoarenes. The method also features the use of feedstock plain NBE, high reactivity, good enantioselectivity, ease of operation and scale-up. Applications in the preparation of chiral optoelectronic material candidates featuring two C-N chiral axes and a chiral ligand for asymmetric C-H activation have also been demonstrated.

12.
J Interpers Violence ; : 8862605241257946, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38842249

ABSTRACT

Exploratory behavior, as a crucial aspect of decision-making, plays an indispensable role in maximizing long-term benefits and is, therefore, essential in promoting adolescents' psychological well-being and social adaptation. Recent studies have shown that this adaptive behavior is influenced by previous early experiences. However, little was known about the associations between specific types of childhood maltreatment and exploratory behavior and the roles of individual motivational and cognitive factors in these relationships. The present study aimed to examine whether the subtypes of maltreatment, that is, threat and deprivation, would influence adolescents' exploratory behavior, the mediating role of sensation seeking, and the moderating role of executive function. Using a sample of 720 Chinese adolescents (Mage = 13.29, SDage = 0.82, 54.8% female), we found that sensation seeking fully mediated the relationship between threat and exploratory behavior. That is, adolescents who experienced threat were more likely to increase sensation seeking, which further promote exploratory activities. Moreover, executive function was a second-stage moderator of this full mediation pathway, with the mediating effect of sensation seeking between threat and exploratory behavior increasing with the enhancement of executive function. However, we did not observe the mediating effect of sensation seeking and the second-stage moderating effect of executive function on the relationship between deprivation and exploration. Considering the distinct impact mechanisms of threat and deprivation on exploratory behavior, our study provides empirical support for the Dimensional Model of Adversity and Psychopathology, and highlights the critical role of sensation seeking and the necessity of implementing executive function interventions for those experiencing threat experiences.

13.
Cancer Gene Ther ; 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38877164

ABSTRACT

Metastasis is the greatest clinical challenge for UTUCs, which may have distinct molecular and cellular characteristics from earlier cancers. Herein, we provide single-cell transcriptome profiles of UTUC para cancer normal tissue, primary tumor lesions, and lymphatic metastases to explore possible mechanisms associated with UTUC occurrence and metastasis. From 28,315 cells obtained from normal and tumor tissues of 3 high-grade UTUC patients, we revealed the origin of UTUC tumor cells and the homology between metastatic and primary tumor cells. Unlike the immunomicroenvironment suppression of other tumors, we found no immunosuppression in the tumor microenvironment of UTUC. Moreover, it is imperative to note that stromal cells are pivotal in the advancement of UTUC. This comprehensive single-cell exploration enhances our comprehension of the molecular and cellular dynamics of metastatic UTUCs and discloses promising diagnostic and therapeutic targets in cancer-microenvironment interactions.

14.
Life Sci ; 351: 122820, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38857652

ABSTRACT

Alcohol use disorder (AUD) is a common mental illness with high morbidity and disability. The discovery of laboratory biomarkers has progressed slowly, resulting in suboptimal diagnosis and treatment of AUD. This study aimed to identify promising biomarkers, as well as the potential miRNA-mRNA networks associated with AUD pathogenesis. RNA sequencing was performed on plasma-derived small extracellular vesicles (sEVs) from AUD patients and healthy controls (HCs) to harvest miRNAs expression profiles. Machine learning (ML) models were built to screen characteristic miRNAs, whose target mRNAs were analyzed using TargetScan, miRanda and miRDB databases. Gene Expression Omnibus (GEO) datasets (GSE181804 and GSE180722) providing postmortem hippocampal gene expression profiles of AUD subjects were mined. A total of 247 differentially expressed (DE) plasma-derived sEVs miRNAs and 122 DE hippocampal mRNAs were obtained. Then, 22 overlapping sEVs miRNAs with high importance scores were gained by intersecting 5 ML models. As a result, we established a putative sEVs miRNA-hippocampal mRNA network that can effectively distinguish AUD patients from HCs. In conclusion, we proposed 5 AUD-representative sEVs miRNAs (hsa-miR-144-5p, hsa-miR-182-5p, hsa-miR-142-5p, hsa-miR-7-5p, and hsa-miR-15b-5p) that may participate in the pathogenesis of AUD by modulating downstream target hippocampal genes. These findings may provide novel insights into the diagnosis and treatment of AUD.


Subject(s)
Alcoholism , Extracellular Vesicles , Hippocampus , MicroRNAs , RNA, Messenger , Humans , Extracellular Vesicles/metabolism , Extracellular Vesicles/genetics , Hippocampus/metabolism , MicroRNAs/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Male , Alcoholism/genetics , Alcoholism/metabolism , Female , Middle Aged , Adult , Biomarkers/metabolism , Machine Learning , Gene Expression Profiling/methods , Case-Control Studies , Gene Regulatory Networks
15.
Fetal Diagn Ther ; : 1, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38838656

ABSTRACT

INTRODUCTION: The aim of this study was to assess the short- and long-term outcome of selective reduction by fetoscopy-guided bipolar cord coagulation in monochronic twin pregnancies. METHODS: Retrospective analysis was conducted of a consecutive cohort of all monochorionic twin pregnancies treated with fetoscopy-guided bipolar cord coagulation between December 2015 and December 2022 in a single center in China. RESULTS: A total of 43 monochronic twin pregnancies undergoing fetoscopy-guided bipolar cord coagulation were analyzed. There were 5 intrauterine deaths with an 88.4% (38/43) survival rate overall. The preterm premature rupture of the membranes rate was 13.2%, and the preterm birth before 37 and 32 weeks was 42.1% and 13.1%, respectively. An uptrend in the survival rate (78.9 vs. 95.8%, p = 0.086) and a downtrend of procedure time (30 vs. 16.5 min, p = 0.036) were observed over time (period 1 from December 2015 to December 2019 verses period 2 from January 2020 to December 2022). Long-term outcome was assessed in 94.6% (35/37) of survivors, and 91.4% (32/35) had normal neurodevelopmental outcome. CONCLUSION: Fetoscopy-guided bipolar cord coagulation for fetal reduction in complicated monochorionic twin pregnancies could achieve a favorable short- and long-term outcome, especially in experienced hands.

17.
Int J Mol Sci ; 25(10)2024 May 08.
Article in English | MEDLINE | ID: mdl-38791146

ABSTRACT

Crohn's disease (CD) is a subtype of inflammatory bowel disease (IBD) characterized by transmural disease. The concept of transmural healing (TH) has been proposed as an indicator of deep clinical remission of CD and as a predictor of favorable treatment endpoints. Understanding the pathophysiology involved in transmural disease is critical to achieving these endpoints. However, most studies have focused on the intestinal mucosa, overlooking the contribution of the intestinal wall in Crohn's disease. Multi-omics approaches have provided new avenues for exploring the pathogenesis of Crohn's disease and identifying potential biomarkers. We aimed to use transcriptomic and proteomic technologies to compare immune and mesenchymal cell profiles and pathways in the mucosal and submucosa/wall compartments to better understand chronic refractory disease elements to achieve transmural healing. The results revealed similarities and differences in gene and protein expression profiles, metabolic mechanisms, and immune and non-immune pathways between these two compartments. Additionally, the identification of protein isoforms highlights the complex molecular mechanisms underlying this disease, such as decreased RTN4 isoforms (RTN4B2 and RTN4C) in the submucosa/wall, which may be related to the dysregulation of enteric neural processes. These findings have the potential to inform the development of novel therapeutic strategies to achieve TH.


Subject(s)
Colon , Crohn Disease , Intestinal Mucosa , Proteomics , Humans , Crohn Disease/metabolism , Crohn Disease/pathology , Crohn Disease/genetics , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Proteomics/methods , Colon/metabolism , Colon/pathology , Transcriptome , Male , Female , Adult , Gene Expression Profiling , Biomarkers , Middle Aged , Multiomics
18.
Plant Physiol Biochem ; 211: 108683, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38714129

ABSTRACT

Jasmonic acid (JA) plays crucial functions in plant stress response, and the synergistic interaction between JA and abscisic acid (ABA) signaling is implicated to help plants adapt to environmental challenges, whereas the underlying molecular mechanism still needs to be revealed. Here, we report that OsJAZ10, a repressor in the JA signaling, represses rice drought tolerance via inhibition of JA and ABA biosynthesis. Function loss of OsJAZ10 markedly enhances, while overexpression of OsJAZ10ΔJas reduces rice drought tolerance. The osjaz10 mutant is more sensitive to exogenous ABA and MeJA, and produces higher levels of ABA and JA after drought treatment, indicating OsJAZ10 represses the biosynthesis of these two hormones. Mechanistic study demonstrated that OsJAZ10 physically interacts with OsMYC2. Transient transcriptional regulation assays showed that OsMYC2 activates the expression of ABA-biosynthetic gene OsNCED2, JA-biosynthetic gene OsAOC, and drought-responsive genes OsRAB21 and OsLEA3, while OsJAZ10 prevents OsMYC2 transactivation of these genes. Further, the electrophoretic mobility shift assay (EMSA) confirmed that OsMYC2 directly binds to the promoters of OsNCED2 and OsRAB21. Electrical activity has been proposed to activate JA biosynthesis. Interestingly, OsJAZ10 inhibits the propagation of osmotic stress-elicited systemic electrical signals, indicated by the significantly increased PEG-elicited slow wave potentials (SWPs) in osjaz10 mutant, which is in accordance with the elevated JA levels. Collectively, our findings establish that OsJAZ10 functions as a negative regulator in rice drought tolerance by repressing JA and ABA biosynthesis, and reveal an important mechanism that plants integrate electrical events with hormone signaling to enhance the adaption to environmental stress.


Subject(s)
Abscisic Acid , Cyclopentanes , Droughts , Gene Expression Regulation, Plant , Oryza , Oxylipins , Plant Proteins , Signal Transduction , Oryza/genetics , Oryza/metabolism , Oryza/physiology , Cyclopentanes/metabolism , Oxylipins/metabolism , Plant Proteins/metabolism , Plant Proteins/genetics , Abscisic Acid/metabolism , Plant Growth Regulators/metabolism , Drought Resistance
19.
ACS Omega ; 9(18): 20185-20195, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38737014

ABSTRACT

The absolute structures of a pair of infinite Na(H2O)4+-connected ε-Keggin-Al13 species (Na-ε-K-Al13) that were inversion structures and mirror images of each other were determined. Single crystals obtained by adding A2SO4 (A = Li, Na, K, Rb, or Cs) solution to NaOH-hydrolyzed AlCl3 solution were subjected to X-ray structure analyses. The statistical results for 36 single crystals showed that all the crystals had almost the same unit cell parameter, belonged to the same F4̅3m space group, and possessed the same structural formula [Na(H2O)4AlO4Al12(OH)24(H2O)12](SO4)4·10H2O. However, the crystals had two inverse absolute structures (denoted A and B), which had a crystallization ratio of 1:1. From Li+ to Cs+, with increasing volume of the cation coexisting in the mother solution, the degree of disorder of the four H2O molecules in the Na(H2O)4+ hydrated ion continuously decreased; they became ordered when the cation was Cs+. Absolute structures A and B are the first two infinite aluminum polycations connected by statistically occupied [(Na1/4)4(H2O)4]+ hydrated ions. The three-dimensional structure of the infinite Na-ε-K-Al13 species can be regarded as the assembly of finite ε-K-Al13 species linked by [(Na1/4)4(H2O)4]+ in a 1:1 ratio. In this assembly, each [(Na1/4)4(H2O)4]+ is connected to four ε-K-Al13 and each ε-K-Al13 is also connected to four [(Na1/4)4(H2O)4]+ in tetrahedral orientations to form a continuous rigid framework structure, which has an inverse spatial orientation between absolute structure A and B. This discovery clarifies that the ε-K-Al13 (or ε-K-GaAl12) species in Na[MO4Al12(OH)24(H2O)12](XO4)4·nH2O (M = Al, Ga; X = S, Se; n = 10-20) exists as discrete groups and deepens understanding of the formation and evolution process of polyaluminum species in forcibly hydrolyzed aluminum salt solution. The reason why Na+ statistically occupies the four sites was examined, and a formation and evolution mechanism of the infinite Na-ε-K-Al13 species was proposed.

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