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Layered double hydroxides (LDHs) have emerged as promising catalysts for various acid–base catalytic reactions. Due to their unique structure and regulatable dual acid–base properties, they offer more environmentally friendly and sustainable alternatives to traditional liquid acid and base catalysts. This study introduces the structural composition, preparation methods, and acid–base catalytic properties of LDH-based catalysts. Recent application progress in LDHs and rehydrated LDHs, LDH-based metal nanocatalysts, and LDH-based mixed metal oxide catalysts used as solid acid–base catalysts in acid–base green catalytic conversion is reviewed. The challenges and prospects of LDH-based catalysts as green and sustainable catalysts are summarized and proposed. [ABSTRACT FROM AUTHOR]

Background and Purpose: The causal relationship between altered host microbiome composition, especially the respiratory tract microbiome, and the occurrence of pulmonary hypertension (PH) has not yet been studied. An increased abundance of airway streptococci is seen in patients with PH compared with healthy individuals. This study aimed to determine the causal link between elevated airway exposure to Streptococcus and PH. Experimental Approach: The dose‐, time‐ and bacterium‐specific effects of Streptococcus salivarius (S. salivarius), a selective streptococci, on PH pathogenesis were investigated in a rat model established by intratracheal instillation. Key Results: Exposure to S. salivarius successfully induced typical PH characteristics, such as elevated right ventricular systolic pressure (RVSP), right ventricular hypertrophy (Fulton's index) and pulmonary vascular remodelling, in a dose‐ and time‐dependent manner. Moreover, the S. salivarius‐induced characteristics were absent in either the inactivated S. salivarius (inactivated bacteria control) treatment group or the Bacillus subtilis (active bacteria control) treatment group. Notably, S. salivarius‐induced PH is characterized by elevated inflammatory infiltration in the lungs, in a pattern different from the classic hypoxia‐induced PH model. Moreover, in comparison with the SU5416/hypoxia‐induced PH model (SuHx‐PH), S. salivarius‐induced PH causes similar histological changes (pulmonary vascular remodelling) but less severe haemodynamic changes (RVSP, Fulton's index). S. salivarius‐induced PH is also associated with altered gut microbiome composition, suggesting potential communication of the lung‐gut axis. Conclusion and Implications: This study provides the first evidence that the delivery of S. salivarius in the respiratory tract could cause experimental PH in rats. [ABSTRACT FROM AUTHOR]

Chronic obstructive pulmonary disease (COPD) is a common respiratory disease. The Huofeitong tablet (HFTT), a Chinese compound medicine, exhibits an unambiguous therapeutic effect on COPD. However, the mechanism of its therapeutic effect on COPD is unclear. This study aimed to investigate the effect of HFTT on COPD and its mechanism. The changes in pulmonary function and the inflammatory factors in rats were determined via histopathology and bronchoalveolar lavage fluid. The mechanism of HFTT in COPD treatment was revealed using UPLC-Q-TOF-MS/MS and multivariate statistical analysis. Results showed that after HFTT treatment, the lung function began to recover, the lung tissue improved, and the TNF-α and IL-6 levels decreased, suggesting that HFTT had a therapeutic effect on COPD. In addition, 12 potential biomarkers, including malonate, urea-1-carboxylate, pyruvate, l -cysteate, glutathione, 2-deoxy-α- d -ribose1-phosphate, 3-fumarylpyruvate, 3-maleylpyruvate, 2-inosose, urate, allantoin, and inosine were screened. They associated with COPD development and concentrated in glutathione metabolism, glyoxylate and dicarboxylate metabolism, secondly concentrated in pyruvate metabolism, glycolysis/gluconeogenesis, pentose phosphate pathway, citrate cycle, glycine, serine and threonine metabolism, inositol phosphate, and purine metabolism. This study contributes to the development and application of HFTT in COPD treatment and provides a theoretical basis for COPD diagnosis, prevention, and treatment. [Display omitted] • A rat model of COPD was established for the first time to explore the therapeutic effect of huofeitong tablet. • The mechanism of huofeitong tablet on COPD was expounded from metabonomics. • 12 potential biomarkers were found in serum and associated with COPD development. [ABSTRACT FROM AUTHOR]

Prostate cancers that progress during androgen-deprivation therapy often overexpress the androgen receptor (AR) and depend on AR signaling for growth. In most cases, increased AR expression occurs without gene amplification and may be due to altered transcriptional regulation. The transcription factor nuclear factor (NF)-kappaB, which is implicated in tumorigenesis, functions as an important downstream substrate of mitogen-activated protein kinase, phosphatidylinositol 3-kinase, AKT, and protein kinase C and plays a role in other cancer-associated signaling pathways. NF-kappaB is an important determinant of prostate cancer clinical biology, and therefore we investigated its role in the regulation of AR expression. We found that NF-kappaB expression in prostate cancer cells significantly increased AR mRNA and protein levels, AR transactivation activity, serum prostate-specific antigen levels, and cell proliferation. NF-kappaB inhibitors decrease AR expression levels, prostate-specific antigen secretion, and proliferation of prostate cancer cells in vitro. Furthermore, inhibitors of NF-kappaB demonstrated anti-tumor activity in androgen deprivation-resistant prostate cancer xenografts. In addition, levels of both NF-kappaB and AR were strongly correlated in human prostate cancer. Our data suggest that NF-kappaB can regulate AR expression in prostate cancer and that NF-kappaB inhibitors may have therapeutic potential.

Molecular mechanisms through which MYCN expression contributes to the malignant phenotype of neuroblastoma are unknown. We performed a genome-widegene expression analysis of 40 well-characterized neuroblastic tumors and 12 cell lines to identify genes and biological pathways associated with MYCN expression. Gene expression was validated by reverse transcription-PCR and immunohistochemistry using tissue arrays. Two hundred twenty-two of 62,839 oligonucleotide probe sets detected expression of genes that were strongly associated with MYCN expression. Differentially expressed genes included examples of known oncogenes, genes associated with neural differentiation, and genes related to cell proliferation. Expression of a subset of these genes was altered after transfection of a neuroblastoma cell line, SK-N-ER, with a MYCN expressing gene construct when protein synthesis was inhibited and have consensus MYCN binding E-box sequences in their promotor regions, suggesting they represent direct targets. Several novel genes/expressed sequences were identified as overexpressed and most likely coamplified with MYCN in a subset of cases. A classification model to identify neuroblastomas with high levels of MYCN expression was developed based on expression profiles. The identification of coexpressed and coamplified genes associated with MYCN overexpression in neuroblastoma suggests biochemical pathways that contribute to the malignant behavior of these tumors and forms a basis for molecular classification.

Several nonrandom chromosomal abnormalities have been associated with neuroblastoma (NB). However, the relationship of each genetic event to the clinical course of disease is not firmly established. We have performed a genome-wide allelic scan of NB to identify regions with frequent allelic imbalance (AI) and correlate the allelotype with clinical features of disease. Nineteen tumors from patients across the spectrum of NB were used. Genome-wide allelotype was performed using 169 fluorescently labeled microsatellite markers from the Weber 9a human screening set (Research Genetics, Huntsville, AL) and 48 independent markers for high-density analysis of selected regions. Eleven chromosomal regions had AI in >25% of tumors including loci known previously to be frequently altered such as 1p36 (10 of 19; 52%), 2p (9 of 19; 47%), 17q (8 of 19; 42%), 11q23 (8 of 19; 42%), 14q32 (7 of 19; 37%), 19q (6 of 19; 31%), 7q (6 of 19; 31%), 9p21 (5 of 19; 26%), and three novel regions of frequent AI at 10p11-p15 (7 of 19; 40%), 12q24.1 (5 of 19; 26%), and 8qcen-q24 (5 of 19; 26%). AI of four regions (8q, 10p, 19q, and 12q) allowed the distinction of two genetic groups that matched clinical significant subgroups of NB. AI at 12q24 and 19q13 was found exclusively in high-risk local-regional tumors, whereas AI at 10p11 and 8q appeared to be specific for stage 4 tumors with MCYN amplification. Spontaneously remitting or quiescent tumors were intact at all of the regions described above.