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1.
Environ Sci Ecotechnol ; 23: 100493, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39430728

RESUMO

Wastewater treatment plants (WWTPs) represent one of biotechnology's largest and most critical applications, playing a pivotal role in environmental protection and public health. In WWTPs, activated sludge (AS) plays a major role in removing contaminants and pathogens from wastewater. While metagenomics has advanced our understanding of microbial communities, it still faces challenges in revealing the genomic heterogeneity of cells, uncovering the microbial dark matter, and establishing precise links between genetic elements and their host cells as a bulk method. These issues could be largely resolved by single-cell sequencing, which can offer unprecedented resolution to show the unique genetic information. Here we show the high-throughput single-cell sequencing to the AS microbiome. The single-amplified genomes (SAGs) of 15,110 individual cells were clustered into 2,454 SAG bins. We find that 27.5% of the genomes in the AS microbial community represent potential novel species, highlighting the presence of microbial dark matter. Furthermore, we identified 1,137 antibiotic resistance genes (ARGs), 10,450 plasmid fragments, and 1,343 phage contigs, with shared plasmid and phage groups broadly distributed among hosts, indicating a high frequency of horizontal gene transfer (HGT) within the AS microbiome. Complementary analysis using 1,529 metagenome-assembled genomes from the AS samples allowed for the taxonomic classification of 98 SAG bins, which were previously unclassified. Our study establishes the feasibility of single-cell sequencing in characterizing the AS microbiome, providing novel insights into its ecological dynamics, and deepening our understanding of HGT processes, particularly those involving ARGs. Additionally, this valuable tool could monitor the distribution, spread, and pathogenic hosts of ARGs both within AS environments and between AS and other environments, which will ultimately contribute to developing a health risk evaluation system for diverse environments within a One Health framework.

2.
MycoKeys ; 108: 15-45, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39220353

RESUMO

During a survey of the diversity of lignicolous fungi in Yunnan Province, China, we collected and identified five microfungi species from dead woody litters of Castanopsis trees in terrestrial habitats. Through both morphological comparisons and phylogenetic analyses of multi-gene sequences, we identified two taxa as new species and three collections as new host records within Pleosporales. Pseudolophiostomalincangense sp. nov. is introduced as a sexual morph in Lophiostomataceae, Pleopunctumbaoshanense sp. nov. is introduced as a hyphomycetous fungi in Phaeoseptaceae, and Paraphomaaquatica as a first report of sexual morph in Paraphoma. In addition, Occultibambusakunmingensis and Pleopunctummegalosporum were isolated for the first time from the dead twigs of Castanopsisdelavayi and C.calathiformis, respectively. Comprehensive morphological descriptions, illustrations, and phylogenetic analysis results are provided for the above-mentioned species.

3.
Org Lett ; 26(32): 6819-6824, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39106047

RESUMO

With alanine as a transient directing group, Pd-catalyzed regioselective alkynylation at the indole C4-position was successfully established in a good yield. The total synthesis of the PAF antagonist demonstrated the synthetic utility of this protocol. The regioselectivity was explicitly proven by the prepared C4-selective palladacycle intermediate in the catalytic process and the DFT calculation of the energy barriers of C4- and C2-site-selective C-H activation of indole.

4.
Org Biomol Chem ; 21(43): 8695-8701, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37861676

RESUMO

Herein, we have reported an environmentally friendly asymmetric aldol reaction between isatins and ketones catalyzed by double-hydrogen-bonded primary amine organocatalysts on water under mild conditions. Enantioenriched 3-hydroxy-2-oxindoles were obtained in high yields (up to 99%) and excellent stereoselectivities (up to 99 : 1 dr and 99% ee) under optimal conditions. Furthermore, the model reaction involving isatin and cyclohexanone was successfully scaled to 10 mmol with no reduction in yield or stereoselectivity. In addition, the catalyst was recovered via simple filtration and was subsequently reused on water, which highlights its good application potential.

5.
J Appl Microbiol ; 134(11)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37883533

RESUMO

AIM: To elucidate the association between gut microbiota, short-chain fatty acids (SCFAs), and glucolipid metabolism in women with large for gestational age (LGA) infants. METHODS AND RESULTS: A single-center, observational prospective cohort study was performed at a tertiary hospital in Wenzhou, China. Normal pregnant women were divided into LGA group and appropriate for gestational age (AGA) group according to the neonatal birth weight. Fecal samples were collected from each subject before delivery for the analysis of gut microbiota composition (GMC) and SCFAs. Blood samples were obtained at 24-28 weeks of gestation age to measure fasting blood glucose and fasting insulin levels, as well as just before delivery to assess serum triglycerides, total cholesterol, high-density lipoprotein (HDL), and low-density lipoprotein. The GMC exhibited differences at various taxonomic levels. Within the Firmicutes phylum, genus Lactobacillus, genus Clostridium, species Lactobacillus agil, and species Lactobacillus salivarius were enriched in the LGA group. Microbispora at genus level, Microbispora rosea at species level belonging to the Actinobacteria phylum, Neisseriales at order level, Bartonellaceae at family level, Paracoccus aminovorans, and Methylobacterium at genus level from the Proteobacteria phylum were more abundant in the LGA group. In contrast, within the Bacteroidetes phylum, Prevotella at genus level and Parabacteroides distasonis at species level were enriched in the AGA group. Although there were few differences observed in SCFA levels and most glucolipid metabolism indicators between the two groups, the serum HDL level was significantly lower in the LGA group compared to the AGA group. No significant relevance among GMC, SCFAs, and glucolipid metabolism indicators was found in the LGA group or in the AGA group. CONCLUSIONS: Multiple different taxa, especially phylum Firmicutes, genus Prevotella, and genus Clostridium, might play an important role in excessive fetal growth, and LGA might be associated with the lower serum HDL level.


Assuntos
Microbioma Gastrointestinal , Gestantes , Feminino , Humanos , Recém-Nascido , Gravidez , Peso ao Nascer , Ácidos Graxos Voláteis , Idade Gestacional , Recém-Nascido Grande para a Idade Gestacional , Estudos Prospectivos
6.
Front Genet ; 14: 1175864, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37388929

RESUMO

Objective: DNA methylation plays a potential role in the pathogenesis of Alzheimer's disease (AD). However, little is known about the global changes of blood leukocyte DNA methylome profiles from Chinese patients with mild cognitive impairment (MCI) and with AD, or the specific DNA methylation-based signatures associated with MCI and AD. In this study, we sought to dissect the characteristics of blood DNA methylome profiles in MCI- and AD-affected Chinese patients with the aim of identifying novel DNA methylation biomarkers for AD. Methods: In this study, we profiled the DNA methylome of peripheral blood leukocytes from 20 MCI- and 20 AD-affected Chinese patients and 20 cognitively healthy controls (CHCs) with the Infinium Methylation EPIC BeadChip array. Results: We identified significant alterations of the methylome profiles in MCI and AD blood leukocytes. A total of 2,582 and 20,829 CpG sites were significantly and differentially methylated in AD and MCI compared with CHCs (adjusted p < 0.05), respectively. Furthermore, 441 differentially methylated positions (DMPs), aligning to 213 unique genes, were overlapped by the three comparative groups of AD versus CHCs, MCI versus CHCs, and AD versus MCI, of which 6 and 5 DMPs were continuously hypermethylated and hypomethylated in MCI and AD relative to CHCs (adjusted p < 0.05), respectively, such as FLNC cg20186636 and AFAP1 cg06758191. The DMPs with an area under the curve >0.900, such as cg18771300, showed high potency for predicting MCI and AD. In addition, gene ontology and pathway enrichment results showed that these overlapping genes were mainly involved in neurotransmitter transport, GABAergic synaptic transmission, signal release from synapse, neurotransmitter secretion, and the regulation of neurotransmitter levels. Furthermore, tissue expression enrichment analysis revealed a subset of potentially cerebral cortex-enriched genes associated with MCI and AD, including SYT7, SYN3, and KCNT1. Conclusion: This study revealed a number of potential biomarkers for MCI and AD, also highlighted the presence of epigenetically dysregulated gene networks that may engage in the underlying pathological events resulting in the onset of cognitive impairment and AD progression. Collectively, this study provides prospective cues for developing therapeutic strategies to improve cognitive impairment and AD course.

7.
Healthcare (Basel) ; 11(10)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37239663

RESUMO

This study aimed to investigate the effects of a beauty program on the self-perception of aging and depression among the community-dwelling older adults in an agricultural area in Taiwan. Twenty-nine older adults aged 65 and above in one agricultural community care center completed the program. Based on cosmetic therapy, the beauty program consisted of 13 sessions focused on facial skin care, make-up application, and massage with essential oils. Each 90 min session of the program was conducted in groups once a week for 13 weeks. This study applied the mixed methods approach, and data were gathered through questionnaire surveys, interviews, and observation. Before and after the beauty program, the elderly individuals' self-perceptions of aging and depression were assessed using the Attitudes towards Old People Scale (ATOPS) and Taiwanese Depression Questionnaire (TDQ), respectively. The participants' ATOPS scores after the program were significantly higher than those examined before the program (p < 0.001), and their TDQ scores were significantly lower than those before the program (p < 0.001). Additionally, the participants' body images were improved, the participants disrupted their stereotypes about makeup, and they were willing to gradually maintain their appearance. Overall, the beauty program was effective for enhancing the self-perceptions of aging and reducing depression in older adults in rural Taiwan. Further research with a larger population of older individuals, male older adults, or frail older adults is needed to examine the specific effects of the beauty program.

8.
J Org Chem ; 87(22): 15547-15558, 2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36306342

RESUMO

Pyrano[4,3-c]pyridine-diones, which are the key skeleton of bioactive compounds and functional materials, are usually prepared via a multistep synthesis using expensive substrates. This work demonstrates that Rh(III)-catalyzed dual C(sp2)-H functionalization and C-O/C-N annulation of monoamide fumarates can produce pyrano[4,3-c]pyridine-1,5(6H)-diones in high yield (up to 82%) in a single step. The substrates of monoamide fumarates and acetylenes are structurally simple, readily available, and inexpensive. The additive AgSbF6 effectively raised the yields. On account of easier dehydrogenation of OH in the COOH group than NH in the amide group in the reaction, the process first undergoes C-O annulation and then is succeeded by C-N annulation.


Assuntos
Ródio , Ródio/química , Estrutura Molecular , Catálise , Fumaratos , Piridinas/química
9.
BMC Med ; 20(1): 303, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36096786

RESUMO

BACKGROUND: Preeclampsia (PE) is a multisystemic maternal syndrome with substantial maternal and fetal morbidity and mortality. Currently, there is no clinically viable non-invasive biomarker assay for early detection, thus limiting the effective prevention and therapeutic strategies for PE. METHODS: We conducted a discovery-training-validation three-phase retrospective and prospective study with cross-platform and multicenter cohorts. The initial biomarkers were discovered and verified in tissue specimens by small RNA sequencing and qRT-PCR. A miRNA signature (miR2PE-score) was developed using Firth's bias-reduced logistic regression analysis and subsequently validated in two independent multinational retrospective cohorts and two prospective plasma cohorts. RESULTS: We initially identified five PE-associated differentially expressed miRNAs from miRNA sequencing data and subsequently validated two miRNAs (miR-196b-5p and miR-584-5p) as robust biomarkers by association analysis with clinical characteristics and qRT-PCR in tissue specimens in the discovery phase. Using Firth's bias-reduced logistic regression analysis, we developed the miR2PE-score for the early detection of PE. The miR2PE-score showed a high diagnostic performance with an area under the receiver operating characteristic curve (AUROC) of 0.920, 0.848, 0.864, and 0.812 in training, internal, and two external validation cross-platform and multicenter cohorts, respectively. Finally, we demonstrated the non-invasive diagnostic performance of the miR2PE-score in two prospective plasma cohorts with AUROC of 0.933 and 0.787. Furthermore, the miR2PE-score revealed superior performance in non-invasive diagnosis compared with previously published miRNA biomarkers. CONCLUSIONS: We developed and validated a novel and robust blood-based miRNA signature, which may serve as a promising clinically applicable non-invasive tool for the early detection of PE.


Assuntos
MicroRNAs , Pré-Eclâmpsia , Biomarcadores Tumorais/genética , Feminino , Humanos , MicroRNAs/genética , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/genética , Estudos Prospectivos , Estudos Retrospectivos
10.
J Clin Lab Anal ; 36(2): e24165, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34997982

RESUMO

BACKGROUND: Ovarian cancer is the gynecologic tumor with the highest fatality rate, and high-grade serous ovarian cancer (HGSOC) is the most common and malignant type of ovarian cancer. One important reason for the poor prognosis of HGSOC is the lack of effective diagnostic and prognostic biomarkers. New biomarkers are necessary for the improvement of treatment strategies and to ensure appropriate healthcare decisions. METHODS: To construct the co-expression network of HGSOC samples, we applied weighted gene co-expression network analysis (WGCNA) to assess the proteomic data obtained from the Clinical Proteomic Tumor Analysis Consortium (CPTAC), and module-trait relationship was then analyzed and plotted in a heatmap to choose key module associated with HGSOC. Subsequently, hub genes with high connectivity in key module were identified by Cytoscape software. Furthermore, the biomarkers were selected through survival analysis, followed by evaluation using the relative operating characteristic (ROC) analysis. RESULTS: A total of 9 modules were identified by WGCNA, and module-trait analysis revealed that the brown module was significantly associated with HGSOC (cor = 0.7). Ten hub genes with the highest connectivity were selected by protein-protein interaction analysis. After survival and ROC analysis, ALB, APOB and SERPINA1 were suggested to be the biomarkers, and their protein levels were positively correlated with HGSOC prognosis. CONCLUSION: We conducted the first gene co-expression analysis using proteomic data from HGSOC samples, and found that ALB, APOB and SERPINA1 had prognostic value, which might be applied for the treatment of HGSOC in the future.


Assuntos
Biomarcadores Tumorais/genética , Cistadenocarcinoma Seroso/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas/genética , Apolipoproteínas B/análise , Apolipoproteínas B/genética , Biomarcadores Tumorais/análise , Feminino , Redes Reguladoras de Genes , Humanos , Prognóstico , Proteômica , Curva ROC , Albumina Sérica Humana/análise , Albumina Sérica Humana/genética , Análise de Sobrevida , alfa 1-Antitripsina/análise , alfa 1-Antitripsina/genética
11.
Comput Inform Nurs ; 40(8): 571-579, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34740222

RESUMO

Nursing information system introduction is an important measure for hospital nursing departments to promote the clinical practice of nursing with both efficiency and quality. A comparison of two cross-sectional study designs was adopted, and the information systems success model, as proposed by DeLone and McLean (2003), was used to explore the effectiveness of the six dimensions of system quality, information quality, service quality, use, user satisfaction, and net benefits at 6 and 12 months after the introduction launch of the nursing information system in hospitals. Multiple regression analysis was used across the two cross-sectional studies. The research results found that the nursing information system conformed to the information systems success model, and half a year to 1 year after the introduction of the nursing information system, use affected the nursing information system net benefits via the mediator variable of user satisfaction; however, the effect of full mediation changed to partial mediation effect with time. The research results can be used as a reference for hospitals and nursing administrators for the newly developed nursing information system.


Assuntos
Hospitais de Ensino , Sistemas de Informação , Estudos Transversais , Humanos , Inquéritos e Questionários , Taiwan
12.
PLoS One ; 16(4): e0249997, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33914752

RESUMO

Second-generation antipsychotics (SGAs) play a critical role in current treatment of schizophrenia (SCZ). It has been observed that sinus bradycardia, rare but in certain situations life threatening adverse drug reaction, can be induced by SGAs across different schizophrenia populations. However, the roles of genetic factors in this phenomenon have not been studied yet. In the present study, a genome-wide association study of single nucleotide polymorphisms (SNPs) was performed on Chinese Han SCZ patients to identify susceptibility loci that were associated with sinus bradycardia induced by SGAs. This study applied microarray to obtain genotype profiles of 88 Han Chinese SCZ patients. Our results found that there were no SNPs had genome-wide significant association with sinus bradycardia induced by SGAs. The top GWAS hit located in gene KIAA0247, which mainly regulated by the tumor suppressor P53 and thus plays a role in carcinogenesis based on resent research and it should not be a susceptibility locus to sinus bradycardia induced by SGAs. Using gene-set functional analysis, we tested that if top 500 SNPs mapped genes were relevant to sinus bradycardia. The result of gene prioritization analysis showed CTNNA3 was strongly correlated with sinus bradycardia, hinting it was a susceptibility gene of this ADR. Our study provides a preliminary study of genetic variants associated with sinus bradycardia induced by SGAs in Han Chinese SCZ patients. The discovery of a possible susceptibility gene shed light on further study of this adverse drug reaction in Han Chinese SCZ patients.


Assuntos
Antipsicóticos/efeitos adversos , Bradicardia/etiologia , Estudo de Associação Genômica Ampla , Esquizofrenia/genética , Adulto , Antipsicóticos/uso terapêutico , Bradicardia/genética , China , Feminino , Genótipo , Humanos , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Mapas de Interação de Proteínas/genética , Esquizofrenia/tratamento farmacológico , Esquizofrenia/patologia , Proteína Supressora de Tumor p53/metabolismo , alfa Catenina/genética
13.
Org Biomol Chem ; 19(7): 1610-1615, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33528484

RESUMO

Highly enantiopure and bioactive δ-valerolactones and pyrazolones, bearing α-all-carbon quaternary stereocentres, were successfully and sequentially prepared via a one-pot procedure starting from readily available, inexpensive materials, catalysed by a new chiral squaramide under mild reaction conditions. An organocatalytic Michael reaction afforded the valerolactones, while a one-pot Michael-hydrazinolysis-imidization cascade yielded the pyrazolones. This procedure is economically efficient and environmentally benign.

14.
Front Immunol ; 12: 792711, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34975894

RESUMO

Multiple sclerosis (MS) is an autoimmune disease that leads to the demyelination of nerve axons. An increasing number of studies suggest that patients with MS exhibit altered metabolic profiles, which might contribute to the course of MS. However, the alteration of metabolic profiles in Chinese patients with MS and their potential roles in regulating the immune system remain elusive. In this study, we performed a global untargeted metabolomics approach in plasma samples from 22 MS-affected Chinese patients and 21 healthy subjects. A total of 42 differentially abundant metabolites (DAMs) belonging to amino acids, lipids, and carbohydrates were identified in the plasma of MS patients and compared with those in healthy controls. We observed an evident reduction in the levels of amino acids, such as L-tyrosine, L-isoleucine, and L-tryptophan, whereas there was a great increase in the levels of L-glutamic acid and L-valine in MS-affected patients. The levels of lipid and carbohydrate metabolites, such as sphingosine 1-phosphate and myo-inositol, were also reduced in patients with MS. In addition, the concentrations of proinflammatory cytokines, such as IL-17 and TNF-α, were significantly increased, whereas those of several anti-inflammatory cytokines and chemokines, such as IL-1ra, IL-7, and MIP-1α, were distinctly reduced in the plasma of MS patients compared with those in healthy subjects. Interestingly, some DAMs, such as L-tryptophan and sphingosine 1-phosphate, showed an evident negative correlation with changes in the level of TNF-α and IL-17, while tightly positively correlating with altered concentrations of anti-inflammatory cytokines and chemokines, such as MIP-1α and RANTES. Our results revealed that altered metabolomic profiles might contribute to the pathogenesis and course of MS disease by modulating immuno-inflammatory responses in the peripheral system, which is essential for eliciting autoimmune responses in the central nervous system, thus resulting in the progression of MS. This study provides potential clues for developing therapeutic strategies for MS in the near future.


Assuntos
Metabolismo Energético , Metaboloma , Metabolômica , Esclerose Múltipla Crônica Progressiva/sangue , Esclerose Múltipla Recidivante-Remitente/sangue , Adulto , Povo Asiático , Biomarcadores/sangue , Estudos de Casos e Controles , China , Biologia Computacional , Feminino , Humanos , Mediadores da Inflamação/sangue , Masculino , Esclerose Múltipla Crônica Progressiva/diagnóstico , Esclerose Múltipla Crônica Progressiva/etnologia , Esclerose Múltipla Crônica Progressiva/imunologia , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Esclerose Múltipla Recidivante-Remitente/etnologia , Esclerose Múltipla Recidivante-Remitente/imunologia
15.
Org Biomol Chem ; 18(45): 9317, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33179697

RESUMO

Correction for 'N-Primary-amine tetrapeptide-catalyzed highly asymmetric Michael addition of aliphatic aldehydes to maleimides' by Zhi-Hong Du et al., Org. Biomol. Chem., 2020, 18, 6899-6904, DOI: 10.1039/D0OB01457E.

16.
Org Biomol Chem ; 18(35): 6899-6904, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32856662

RESUMO

The highly asymmetric Michael addition reaction between maleimides and aliphatic aldehydes catalyzed by low-loading ß-turn tetrapeptides with excellent yields and enantioselectivities at room temperature was reported. α-Branched and α-unbranched aldehydes both are suitable nucleophiles. N-Aryl, alkyl and hydrogen maleimides all are well tolerated and led to high yields and enantioselectivities. The transformation can be enlarged to the gram scale without decrease in the yield and enantioselectivity. Furthermore, the succinimides were converted into γ-lactams and γ-lactones, showing good practicality of this work. Some reaction intermediates in the proposed reaction mechanism can be captured with the HR-MS method.


Assuntos
Maleimidas
17.
Front Oncol ; 10: 1019, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32695675

RESUMO

Arsenic was recently identified as a pollutant that is a major cause of lung cancer. Since heparin-binding EGF-like growth factor (HB-EGF) was reported to be a promising therapeutic target for lung cancer, we investigated the role and mechanism of HB-EGF during arsenic-induced carcinogenesis and development of lung cancer. HB-EGF expression were upregulated in As-T cells, lung cancer cell lines, and in most lung cancer tissue samples; and HB-EGF activated the EGFR/p-ERK/HIF-1α pathway and induced VEGF by regulating HIF-1α transcription. HIF-1α transcriptional stimulation by HB-EGF was facilitated by PKM2 and played an important role in HB-EGF's effect on cells. An HB-EGF inhibitor(CRM197, cross-reacting material 197) slowed cell proliferation and inhibited migration of As-T and A549 cells, and inhibited tumor growth. PKM2 also played an important role in the proliferation and migration in As-T cells. The positive staining ratios of EGFR phosphorylation (Y1068) and PKM2 were significantly higher in most cases of lung cancer than in paired normal tumor-adjacent lung tissues; and HB-EGF expression levels strongly correlated with p-EGFR expression levels. Thus, HB-EGF drives arsenic-induced carcinogenesis, tumor growth, and lung cancer development via the EGFR/PKM2/HIF-1α pathway.

18.
Org Lett ; 22(11): 4444-4450, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32463241

RESUMO

ß-Turn tetrapeptides were demonstrated to catalyze asymmetric aldol reaction of α-branched aldehydes and α-carbonyl aldehydes, i.e. glyoxylates and α-ketoaldehydes, to biomimetically synthesize acyclic all-carbon quaternary center-bearing 1,4-dicarbonyls in high yield and excellent enantioselectivity under mild conditions. The spatially restricted environment of the tetrapeptide warrants high enantioselectivity and yield with broad substrates. Using this protocol, (R)-pantolactone, the key intermediate of vitamin B5, was readily accessed in a practical, efficient, and environmentally benign process from inexpensive starting materials.


Assuntos
Aldeídos/química , Cetonas/síntese química , Peptídeos/química , Catálise , Cristalografia por Raios X , Cetonas/química , Modelos Moleculares , Estrutura Molecular
19.
Asian J Androl ; 22(4): 414-421, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31489847

RESUMO

The apoptosis that occurs in the immature testis under physiological conditions is necessary for male germ cell development, whereas improper activation of apoptosis can impair spermatogenesis and cause defects in reproduction. We previously demonstrated that in mice, the makorin-2 (Mkrn 2) gene is expressed exclusively in the testis and its deletion leads to male infertility. To understand the potential molecular mechanism, in this study, we found that levels of apoptosis in the testis were abnormally high in the absence of Mkrn 2. To identify specific gene(s) involved, we performed digital gene expression profiling (DGE) and pathway analysis via gene set enrichment analysis (GSEA) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, and we found that MKRN2 inhibits p53 apoptosis effector related to PMP22 (PERP) expression and that levels of the protein in sperm samples have an inverse correlation with infertility levels. GSEA additionally indicated that PERP is a negative regulator of spermatogenesis and that its ectopic expression induces male infertility. Further, Gene Expression Omnibus (GEO) dataset analysis showed that p53, upstream of PERP, was upregulated in oligoasthenoteratozoospermia (OAT). These observations suggest that Mkrn 2 is crucial for protecting germ cells from excessive apoptosis and implicate Mkrn 2-based suppression of the p53/PERP signaling pathway in spermatogenesis and male fertility.


Assuntos
Apoptose/genética , Infertilidade Masculina/genética , Ribonucleoproteínas/genética , Espermatogênese/genética , Animais , Células Cultivadas , Fibroblastos , Perfilação da Expressão Gênica , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Oligospermia/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Teratozoospermia , Testículo , Proteína Supressora de Tumor p53/metabolismo
20.
Chirality ; 31(1): 79-86, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30520127

RESUMO

Enantioselective vinylation of aldehydes via direct catalytic asymmetric Grignard reaction of aldehdyes and the vinyl Grinard reagent is a long-standing challenge. This work demonstrated that the magnesium (S)-3,3'-dimethyl BINOLate enantioselectively catalyze the direct vinylation of aldehydes with the deactivated vinylmagnesium bromide by bis(2-[N,N'-dimethylamino]ethyl) ether (BDMAEE) in the addition of n-butylmagnesium chloride. The highest ee of 63% was achieved up to date.

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