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1.
Org Lett ; 26(29): 6125-6129, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-38994746

RESUMO

The reductive C-Si coupling of chlorosilanes offers efficient access to organosilanes, but its potential for constructing aliphatic ones remains largely unexplored. This manuscript presents a nickel-catalyzed Csp3-Si coupling reaction of unactivated alkyl-Br and R2Si(H)Cl. This work establishes a new approach for synthesizing highly functionalized aliphatic hydrosilanes from readily available chemical feedstocks. The reaction is easily scalable and can accommodate various functional groups, including carboxylic acids, which are usually incompatible with basic conditions.

2.
Adv Sci (Weinh) ; : e2401796, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39044365

RESUMO

Graphene field-effect transistors (GFETs) are widely used in biosensing due to their excellent properties in biomolecular signal amplification, exhibiting great potential for high-sensitivity and point-of-care testing in clinical diagnosis. However, difficulties in complicated fabrication steps are the main limitations for the further studies and applications of GFETs. In this study, a modular fabrication technique is introduced to construct microfluidic GFET biosensors within 3 independent steps. The low-melting metal electrodes and intricate flow channels are incorporated to maintain the structural integrity of graphene and facilitate subsequent sensing operations. The as-fabricated GFET biosensor demonstrates excellent long-term stability, and performs effectively in various ion environments. It also exhibits high sensitivity and selectivity for detecting single-stranded nucleic acids at a 10 fm concentration. Furthermore, when combined with the CRISPR/Cas12a system, it facilitates amplification-free and rapid detection of nucleic acids at a concentration of 1 fm. Thus, it is believed that this modular-fabricated microfluidic GFET may shed light on further development of FET-based biosensors in various applications.

3.
Int J Biol Macromol ; 276(Pt 2): 133973, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39032877

RESUMO

The protein-ligand binding frequently occurs in living organisms and plays a crucial role in the execution of the functions of proteins and drugs. It is also an indispensable part of drug discovery and screening. While the methods for investigating protein-ligand binding are diverse, each has its own objectives, strengths, and limitations, which all influence the choice of method. Many studies concentrate on one or a few specific methods, suggesting that comprehensive summaries are lacking. Therefore in this review, these methods are comprehensively summarized and are discussed in detail: prediction and simulation methods, thermal and thermodynamic methods, spectroscopic methods, methods of determining three-dimensional structures of the complex, mass spectrometry-based methods and others. It is also important to integrate these methods based on the specific objectives of the research. With the aim of advancing pharmaceutical research, this review seeks to deepen the understanding of the protein-ligand binding process.

4.
iScience ; 27(7): 110255, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39021794

RESUMO

The effect on catalytic behavior induced by different morphology of NiO supports has been investigated using the example of gold-catalyzed CO oxidation. Three NiO-supported nanogold consisting of nanogold deposited onto NiO nanorods (NiO-R), nanosheet (NiO-S), and nanodiscs (NiO-D) were prepared. Transmission electron microscopy(TEM)/Scanning transmission electron microscopy(STEM) investigations indicated that Au particles dominantly exposed Au(111) facets virtually independent of NiO architectures. Au/NiO-S displayed a normal Arrhenius-type behavior. Au/NiO-R and Au/NiO-D showed an atypical behavior, characterized by a U-shaped curve of activity vs. temperature, which is attributed to the carbonate accumulation on whose catalytically active sites. On Au/NiO-R, a stable CO-conversion rate of 1.78 molCO gAu -1 h-1 at 30°C was achieved, which is among the higher rates reported so far for supported Au-based systems. DRIFTS measurement identified Auδ+ species as crucial CO adsorption sites promoting CO oxidation, and the catalytic CO oxidation should obey Mars-van Krevelen (<200°C) and Eley-Rideal mechanism (>240°C).

5.
Orphanet J Rare Dis ; 19(1): 247, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38956624

RESUMO

BACKGROUND: The safety and efficacy of vaccination against coronavirus disease 2019 (COVID-19) in patients with lymphangioleiomyomatosis (LAM) is still unclear. This study investigates COVID-19 vaccine hesitancy, vaccine safety and efficacy, and COVID-19 symptoms in LAM patients. RESULTS: In total, 181 LAM patients and 143 healthy individuals responded to the questionnaire. The vaccination rate of LAM patients was 77.34%, and 15.7% of vaccinated LAM patients experienced adverse events. Vaccination decreased the risk of LAM patients developing anorexia [OR: 0.17, 95% CI: (0.07, 0.43)], myalgia [OR: 0.34, 95% CI: (0.13, 0.84)], and ageusia [OR: 0.34, 95% CI: (0.14, 0.84)]. In LAM patients, a use of mTOR inhibitors reduced the risk of developing symptoms during COVID-19, including fatigue [OR: 0.18, 95% CI: (0.03, 0.95)], anorexia [OR: 0.30, 95% CI: (0.09, 0.96)], and ageusia [OR: 0.20, 95% CI: (0.06, 0.67)]. CONCLUSIONS: Vaccination rates in the LAM population were lower than those in the general population, as 22.7% (41/181) of LAM patients had hesitations regarding the COVID-19 vaccine. However, the safety of COVID-19 vaccination in the LAM cohort was comparable to the healthy population, and COVID-19 vaccination decreased the incidence of COVID-19 symptoms in LAM patients. In addition, mTOR inhibitors seem not to determine a greater risk of complications in patients with LAM during COVID-19.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Linfangioleiomiomatose , Humanos , COVID-19/prevenção & controle , COVID-19/epidemiologia , Feminino , Estudos Retrospectivos , Adulto , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/uso terapêutico , Pessoa de Meia-Idade , Masculino , SARS-CoV-2 , Vacinação , China/epidemiologia , População do Leste Asiático
6.
J Hazard Mater ; 476: 135192, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39002479

RESUMO

Microplastics (MPs) are emerging as anthropogenic vectors to form plastisphere, facilitating microbiome colonization and pathogenic dissemination, thus contributing to environmental and health crises across various ecosystems. However, a knowledge gap persists regarding MPs risks and their driving factors in certain unique and vulnerable ecosystems, such as Karst travertine lakes, some of which are renowned World Natural Heritage Sites under ever-increasing tourism pressure. We hypothesized that tourism activities serve as the most important factor of MPs pollution, whereas intrinsic features, including travertine deposition can exacerbate potential environmental risks. Thus, metagenomic approaches were employed to investigate the geographical distribution of the microbiome, antibiotic resistance genes (ARGs), virulence factor genes (VFGs), and their combined environmental risks in Jiuzhaigou and Huanglong, two famous tourism destinations in Southwest China. The plastisphere risks were higher in Huanglong, contradicting our hypothesis that Jiuzhaigou would face more crucial antibiotic risks due to its higher tourist activities. Specifically, the levels of Lipopolysaccharide Lewis and fosD increased by sevenfold and 20-fold, respectively, from upstream to downstream in Huanglong, whereas in Jiuzhaigou, no significant accrual was observed. Structural equation modeling results showed that travertine deposition was the primary contributor to MPs risks in alpine karstic lakes. Our findings suggest that tourism has low impact on MPs risks, possibly because of proper management, and that travertine deposition might act as an MPs hotspot, emphasizing the importance of considering the unique aspects of travertine lakes in mitigating MPs pollution and promoting the sustainable development of World Natural Heritage Sites.

7.
J Org Chem ; 89(14): 10047-10053, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38951997

RESUMO

We have successfully synthesized a series of bidentate ligands by utilizing 2-(trimethylsilyl)phenyl trifluorosulfonate as a precursor for the benzyl group. This method proceeded by inserting a polythiourea into the C═S π-bond, intramolecular ring proton migration, and ring opening. Salient features of this strategy are mild reaction conditions, a novel product structure, excellent stereochemistry, and a good functional group tolerance. Furthermore, a series of density functional theory calculations were performed to gain insights into the transfer mechanism.

8.
Artigo em Inglês | MEDLINE | ID: mdl-39038348

RESUMO

Context: Man-made disasters and natural disasters bring huge losses to human life and property. High-quality nursing teams play an important role in reducing casualty and disability rates in disaster areas, reducing the prognosis of the injured, accelerating community recovery and even promoting social rehabilitation. This work aimed to analyze the current situation and influencing factors of disaster emergency rescue (DER) of nurses in Hunan Province by surveying their knowledge, attitude, and practice of DER in Grade A hospitals. Methods: 1260 nurses working in 13 Grade A hospitals in Hunan Province from March to October 2022 were selected as subjects by a random sampling method and conducted by a questionnaire survey. The general data of the subjects were collected by "behaviors", forming the "nurses' knowledge, attitude, and practice questionnaire, and their DER knowledge, attitude and behavior were evaluated. Results: 1260 questionnaires were distributed, and 1,256 were effectively received, with a recovery rate of 99.68%. The total score of DER-related knowledge of 1.256 investigators was 136.82 ± 9.73 points. Among them, the highest and lowest scores were observed in the Triage (26.79 ± 2.09 points) and the sanitary and anti-epidemic (17.97 ± 1.28 points). The scores of DER attitude of 1256 respondents were close, which were arranged as about 3.87 ± 0.39 (with a range of 4.34 ~ 4.20). 1,256 investigators expressed the highest score in participating in the DER-related courses (4.93 ± 0.34 points) and the lowest score in participating in the on-site DER (2.01 ± 0.13 points). The results showed that they were correlated with gender, educational background, working years, department, and out-of-hospital emergency rescue experience (P ≤ .05), but not with age. The scores of DER-related knowledge and behaviors of hospital nurses were higher in men than in women. The higher the education, the higher the score, and the more the working years. Emergency and ICU nurses scored higher than those in other general departments. In addition, nurses with out-of-hospital emergency rescue experience scored higher than those without. Conclusion: The overall DER-related knowledge, attitude, and practice of hospital nurses is not high. Nursing managers should incorporate disaster nursing into emergency rescue nurses' training, strengthen clinical nurses' training and exercise in DER-related knowledge, pay special attention to DER drills and practices, and provide reasonable and correct DER guidance. Furthermore, it should cultivate the noble social citizenship qualities of clinical nursing nurses, such as the sense of mission to save the dying and heal the injured, the sense of satisfaction in realizing self-worth, and the sense of social responsibility. In addition, it is suggested that a reasonable incentive and reward system be established to encourage hospital nurses to participate in the DER. Due to the limitations of this study, the sample size can be expanded and included in the nurse interview considered in the future to supplement the survey data and further study and analyze nurses' rescue mentality, cognitive influencing factors, and intervention measures to provide more reference for human resource reserve and management of disaster rescue care.

10.
Nat Commun ; 15(1): 6109, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030195

RESUMO

The collective modes of the superconducting order parameter fluctuation can provide key insights into the nature of the superconductor. Recently, a family of superconductors has emerged in non-magnetic kagome materials AV3Sb5 (A = K, Rb, Cs), exhibiting fertile emergent phenomenology. However, the collective behaviors of Cooper pairs have not been studied. Here, we report a distinct collective mode in CsV3-xTaxSb5 using scanning tunneling microscope/spectroscopy. The spectral line-shape is well-described by one isotropic and one anisotropic superconducting gap, and a bosonic mode due to electron-mode coupling. With increasing x, the two gaps move closer in energy, merge into two isotropic gaps of equal amplitude, and then increase synchronously. The mode energy decreases monotonically to well below 2 Δ and survives even after the charge density wave order is suppressed. We propose the interpretation of this collective mode as Leggett mode between different superconducting components or the Bardasis-Schrieffer mode due to a subleading superconducting component.

11.
Crit Rev Clin Lab Sci ; : 1-15, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041650

RESUMO

Immunoglobulin G (IgG) and immunoglobulin M (IgM) testing are commonly used to determine infection status. Typically, the detection of IgM indicates an acute or recent infection, while the presence of IgG alone suggests a chronic or past infection. However, relying solely on IgG and IgM antibody positivity may not be sufficient to differentiate acute from chronic infections. This limitation arises from several factors. The prolonged presence of IgM can complicate diagnostic interpretations, and false positive IgM results often arise from antibody cross-reactivity with various antigens. Additionally, IgM may remain undetectable in prematurely collected samples or in individuals who are immunocompromised, further complicating accurate diagnosis. As a result, additional diagnostic tools are required to confirm infection status. Avidity is a measure of the strength of the binding between an antigen and antibody. Avidity-based assays have been developed for various infectious agents, including toxoplasma, cytomegalovirus (CMV), SARS-CoV-2, and avian influenza, and are promising tools in clinical diagnostics. By measuring the strength of antibody binding, they offer critical insights into the maturity of the immune response. These assays are instrumental in distinguishing between acute and chronic or past infections, monitoring disease progression, and guiding treatment decisions. The development of automated platforms has optimized the testing process by enhancing efficiency and minimizing the risk of manual errors. Additionally, the recent advent of real-time biosensor immunoassays, including the label-free immunoassays (LFIA), has further amplified the capabilities of these assays. These advances have expanded the clinical applications of avidity-based assays, making them useful tools for the diagnosis and management of various infectious diseases. This review is structured around several key aspects of IgG avidity in clinical diagnosis, including: (i) a detailed exposition of the IgG affinity maturation process; (ii) a thorough discussion of the IgG avidity assays, including the recently emerged biosensor-based approaches; and (iii) an examination of the applications of IgG avidity in clinical diagnosis. This review is intended to contribute toward the development of enhanced diagnostic tools through critical assessment of the present landscape of avidity-based testing, which allows us to identify the existing knowledge gaps and highlight areas for future investigation.

13.
Neuroimage ; 297: 120688, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38878916

RESUMO

The human brain is organized as a complex, hierarchical network. However, the structural covariance patterns among brain regions and the underlying biological substrates of such covariance networks remain to be clarified. The present study proposed a novel individualized structural covariance network termed voxel-based texture similarity networks (vTSNs) based on 76 refined voxel-based textural features derived from structural magnetic resonance images. Validated in three independent longitudinal healthy cohorts (40, 23, and 60 healthy participants, respectively) with two common brain atlases, we found that the vTSN could robustly resolve inter-subject variability with high test-retest reliability. In contrast to the regional-based texture similarity networks (rTSNs) that calculate radiomic features based on region-of-interest information, vTSNs had higher inter- and intra-subject variability ratios and test-retest reliability in connectivity strength and network topological properties. Moreover, the Spearman correlation indicated a stronger association of the gene expression similarity network (GESN) with vTSNs than with rTSNs (vTSN: r = 0.600, rTSN: r = 0.433, z = 39.784, P < 0.001). Hierarchical clustering identified 3 vTSN subnets with differential association patterns with 13 coexpression modules, 16 neurotransmitters, 7 electrophysiology, 4 metabolism, and 2 large-scale structural and 4 functional organization maps. Moreover, these subnets had unique biological hierarchical organization from the subcortex-limbic system to the ventral neocortex and then to the dorsal neocortex. Based on 424 unrelated, qualified healthy subjects from the Human Connectome Project, we found that vTSNs could sensitively represent sex differences, especially for connections in the subcortex-limbic system and between the subcortex-limbic system and the ventral neocortex. Moreover, a multivariate variance component model revealed that vTSNs could explain a significant proportion of inter-subject behavioral variance in cognition (80.0 %) and motor functions (63.4 %). Finally, using 494 healthy adults (aged 19-80 years old) from the Southwest University Adult Lifespan Dataset, the Spearman correlation identified a significant association between aging and vTSN strength, especially within the subcortex-limbic system and between the subcortex-limbic system and the dorsal neocortex. In summary, our proposed vTSN is robust in uncovering individual variability and neurobiological brain processes, which can serve as biologically plausible measures for linking biological processes and human behavior.

14.
Orphanet J Rare Dis ; 19(1): 236, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877584

RESUMO

OBJECTIVE: This study aimed to enhance the understanding of the role of estrogen in lymphangioleiomyomatosis(LAM) and to conclude the impact of estrogen-altering events on the condition and recent advances in estrogen-based treatments for LAM. RESULTS: LAM development is strongly linked to mutations in the tuberous sclerosis gene (TSC1/2) and the presence of estrogen. Estrogen plays a significant role in the spread of TSC2-deficient uterine leiomyoma cells to the lungs and the production of pulmonary LAM. Menstruation, pregnancy, estrogen medication, and other events that cause an increase in estrogen levels can trigger the disorder, leading to a sudden worsening of symptoms. Current findings do not support using estrogen-blocking therapy regimens. However, Faslodex, which is an estrogen receptor antagonist, presents new possibilities for future therapeutic approaches in LAM. CONCLUSION: Estrogen is crucial in the development and spread of LAM. The use of estrogen inhibitors or estrogen receptor antagonists alone does not provide good control of the disease or even poses a greater risk, and the use of a combination of mTOR receptor inhibitors, complete estrogen receptor antagonists, estrogen inhibitors, and autophagy inhibitors targeting important signaling pathways in LAM pathogenesis may be of greater benefit to the patient.


Assuntos
Estrogênios , Linfangioleiomiomatose , Linfangioleiomiomatose/metabolismo , Linfangioleiomiomatose/tratamento farmacológico , Linfangioleiomiomatose/patologia , Linfangioleiomiomatose/genética , Humanos , Estrogênios/metabolismo , Feminino
15.
Sci Data ; 11(1): 644, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886364

RESUMO

The Mediterranean mussel, Mytilus galloprovincialis, is a significant marine bivalve species that has ecological and economic importance. This species is robustly resilient and highly invasive. Despite the scientific and commercial interest in studying its biology and aquaculture, there remains a need for a high-quality, chromosome-scale reference genome. In this study, we have assembled a high-quality chromosome-scale reference genome for M. galloprovincialis. The total length of our reference genome is 1.41 Gb, with a scaffold N50 sequence length of 96.9 Mb. BUSCO analysis revealed a 97.5% completeness based on complete BUSCOs. Compared to the four other available M. galloprovincialis assemblies, the assembly described here is dramatically improved in both contiguity and completeness. This new reference genome will greatly contribute to a deeper understanding of the resilience and invasiveness of M. galloprovincialis.


Assuntos
Cromossomos , Genoma , Mytilus , Mytilus/genética , Animais
16.
Appl Opt ; 63(12): 3272-3276, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38856477

RESUMO

Herein we report an electronically controlled tunable fiber-optic attenuator that leverages the microfluidic electro-wetting effect, which enables a fine-tuning of the solid-liquid interface wetting angle to control the micro-reflector, thus regulating the lens fiber coupling efficiency. Theoretical calculations indicated an optical attenuation regulation effect of 0-45.0 dB in the voltage range of 0-30.0 V. Experimental results align closely with theoretical calculations, demonstrating an attenuation range of 0.59-43.0 dB within a voltage variation range of 0-25.0 V, with control accuracy of 0.56 dB. Our study unveils the potential for designing fiber-optic attenuators with varying tuning accuracy by precisely adjusting the solid-liquid interface wetting angle.

17.
Cancer Lett ; 597: 217059, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38876383

RESUMO

5-Methylcytosine (m5C) methylation is a significant post-transcriptional modification that play a crucial role in the development and progression of numerous cancers. Whereas the functions and molecular mechanisms underlying m5C methylation in gliomas remain unclear. This study dedicated to explore changes of m5C levels and the clinical significance of the m5C writer NSUN4 in gliomas. We found that high m5C levels were negatively related to prognosis of patients with glioma. Moreover, gain- and loss-of-function experiments revealed the role of NSUN4 in enhancing m5C modification of mRNA to promote the malignant progression of glioma. Mechanistically speaking, NSUN4-mediated m5C alterations regulated ALYREF binding to CDC42 mRNA, thereby impacting the mRNA stability of CDC42. We also demonstrated that CDC42 promoted glioma proliferation, migration, and invasion by activating the PI3K-AKT pathway. Additionally, rescue experiments proved that CDC42 overexpression weaken the inhibitory effect of NSUN4 knockdown on the malignant progression of gliomas in vitro and in vivo. Our findings elucidated that NSUN4-mediated high m5C levels promote ALYREF binding to CDC42 mRNA and regulate its stability, thereby driving the malignant progression of glioma. This provides theoretical support for targeted the treatment of gliomas.

18.
J Environ Manage ; 364: 121311, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38875977

RESUMO

Soil salinization and sodification, the primary causes of land degradation and desertification in arid and semi-arid regions, demand effective monitoring for sustainable land management. This study explores the utility of partial least square (PLS) latent variables (LVs) derived from visible and near-infrared (Vis-NIR) spectroscopy, combined with remote sensing (RS) and auxiliary variables, to predict electrical conductivity (EC) and sodium absorption ratio (SAR) in northern Xinjiang, China. Using 90 soil samples from the Karamay district, machine learning models (Random Forest, Support Vector Regression, Cubist) were tested in four scenarios. Modeling results showed that RS and Land use alone were unreliable predictors, but the addition of topographic attributes significantly improved the prediction accuracy for both EC and SAR. The incorporation of PLS LVs derived from Vis-NIR spectroscopy led to the highest performance by the Random Forest model for EC (CCC = 0.83, R2 = 0.80, nRMSE = 0.48, RPD = 2.12) and SAR (CCC = 0.78, R2 = 0.74, nRMSE = 0.58, RPD = 2.25). The variable importance analysis identified PLS LVs, certain topographic attributes (e.g., valley depth, elevation, channel network base level, diffuse insolation), and specific RS data (i.e., polarization index of VV + VH) as the most influential predictors in the study area. This study affirms the efficiency of Vis-NIR data for digital soil mapping, offering a cost-effective solution. In conclusion, the integration of proximal soil sensing techniques and highly relevant topographic attributes with the RF model has the potential to yield a reliable spatial model for mapping soil EC and SAR. This integrated approach allows for the delineation of hazardous zones, which in turn enables the consideration of best management practices and contributes to the reduction of the risk of degradation in salt-affected and sodicity-affected soils.


Assuntos
Salinidade , Solo , Solo/química , China , Monitoramento Ambiental/métodos , Tecnologia de Sensoriamento Remoto , Análise dos Mínimos Quadrados
19.
Int J Mol Sci ; 25(11)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38891762

RESUMO

The testis-specific double sex and mab-3-related transcription factor 1 (DMRT1) has long been recognized as a crucial player in sex determination across vertebrates, and its essential role in gonadal development and the regulation of spermatogenesis is well established. Here, we report the cloning of the key spermatogenesis-related DMRT1 cDNA, named Tc-DMRT1, from the gonads of Tridacna crocea (T. crocea), with a molecular weight of 41.93 kDa and an isoelectric point of 7.83 (pI). Our hypothesis is that DMRT1 machinery governs spermatogenesis and regulates gonadogenesis. RNAi-mediated Tc-DMRT1 knockdown revealed its critical role in hindering spermatogenesis and reducing expression levels in boring giant clams. A histological analysis showed structural changes, with normal sperm cell counts in the control group (ds-EGFP) but significantly lower concentrations of sperm cells in the experimental group (ds-DMRT1). DMRT1 transcripts during embryogenesis exhibited a significantly high expression pattern (p < 0.05) during the early zygote stage, and whole-embryo in-situ hybridization confirmed its expression pattern throughout embryogenesis. A qRT-PCR analysis of various reproductive stages revealed an abundant expression of Tc-DMRT1 in the gonads during the male reproductive stage. In-situ hybridization showed tissue-specific expression of DMRT1, with a positive signal detected in male-stage gonadal tissues comprising sperm cells, while no signal was detected in other stages. Our study findings provide an initial understanding of the DMRT1 molecular machinery controlling spermatogenesis and its specificity in male-stage gonads of the key bivalve species, Tridacna crocea, and suggest that DMRT1 predominantly functions as a key regulator of spermatogenesis in giant clams.


Assuntos
Bivalves , Espermatogênese , Testículo , Fatores de Transcrição , Animais , Espermatogênese/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Masculino , Testículo/metabolismo , Testículo/crescimento & desenvolvimento , Bivalves/genética , Bivalves/metabolismo , Bivalves/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Gônadas/metabolismo , Gônadas/crescimento & desenvolvimento , Organismos Hermafroditas/genética , Organismos Hermafroditas/metabolismo , Clonagem Molecular , Filogenia , Sequência de Aminoácidos
20.
JACS Au ; 4(6): 2312-2322, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38938800

RESUMO

Enantioenriched 3-methylpyrrolidine, with its unique chiral nitrogen-containing core skeleton, exists widely in various functional molecules, including natural products, bioactive compounds, and pharmaceuticals. Traditional methods for synthesizing these valuable methyl-substituted heterocycles often involve enzymatic processes or complex procedures with chiral auxiliaries, limiting the substrate scope and efficiency. Efficient catalytic methylation, especially in an enantioselective manner, has been a long-standing challenge in chemical synthesis. Herein, we present a novel approach for the remote and stereoselective installation of a methyl group onto N-heterocycles, leveraging a CoH-catalyzed asymmetric hydromethylation strategy. By effectively combining a commercial cobalt precursor with a modified bisoxazoline (BOX) ligand, a variety of easily accessible 3-pyrrolines can be converted to valuable enantiopure 3-(isotopic labeling)methylpyrrolidine compounds with outstanding enantioselectivity. This efficient protocol streamlines the two-step synthesis of enantioenriched 3-methylpyrrolidine, which previously required up to five or six steps under harsh conditions or expensive starting materials.

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