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1.
Environ Sci Ecotechnol ; 23: 100496, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39469145

RESUMO

Land degradation from water erosion poses a significant threat to water security and ecosystem stability, driving global efforts in soil conservation. Quantitative assessment of soil conservation benefits-both on-site and off-site-is crucial for guiding effective conservation strategies. However, existing methodologies often fall short in quantifying the value of these combined benefits. Here, we present a comprehensive framework for quantifying soil conservation service flows in monetary terms, evaluating the effectiveness of both on-site and off-site measures. Applying this framework to the Yellow River Basin (YRB), we employ cost-avoidance algorithms related to soil fertility maintenance, dredging cost reduction, and mitigation of nonpoint source pollution. Our results reveal that while many areas contribute to both on-site and off-site benefits, over half of the YRB relies predominantly on off-site services. By strategically enhancing key regions-which constitute 30% of the basin-we demonstrate that the overall soil conservation service supply can increase by 64.2% over the multi-year average from 2001 to 2020 compared to a consideration of on-site only. These findings underscore the essential role of off-site services in fully understanding soil conservation needs, particularly in large river basins, and the identified priority areas can offer valuable insights for optimizing soil conservation efforts.

3.
Chem Sci ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39444560

RESUMO

The asymmetric dicarbofunctionalization of alkenes via a radical relay process can provide routes to diverse hydrocarbon derivatives. Three-component carboalkynylation, limited to particular alkyl halides and using readily available cycloketone oxime esters as redox-active precursors, is restricted by the available pool of suitable chiral ligands for broadening the redox potential window of copper complexes and simultaneously creating the enantiocontrol environment. Herein, we report a new hybrid tridentate ligand bearing a guanidine-amide-pyridine unit for photoinduced copper-catalyzed cyanoalkylalkynylation of alkenes. Leveraging the copper catalyst's redox capability is achieved via merging the electron-rich ligand with a readily organized configuration and enhanced absorption in the visible light range, which also facilitates the enantioselectivity. The generality of the catalyst system is exemplified by the efficacy across a number of alkenes, terminal alkynes and cycloketone oxime esters, working smoothly to give alkyne-bearing nitriles with good yields and excellent enantioselectivity. A mechanistic study reveals that the chiral copper catalyst meets the requirements of possessing sufficient reduction ability, good light absorption properties, and appropriate steric hindrance.

4.
Chem Commun (Camb) ; 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39450603

RESUMO

A series of oxazole-fused succinimides bearing vicinal quaternary carbon centers were synthesized. This process takes place between nitroolefins and azlactones in the presence of a bifunctional chiral guanidine-sulfonamide organocatalyst, followed by a Nef-type transformation under the treatment of DMAP/Ac2O. Several control experiments were conducted to propose the mechanism.

5.
Nat Med ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39354195

RESUMO

Refractory or relapsed T cell acute lymphoblastic leukemia (r/r T-ALL) patients have poor prognoses, due to the lack of effective salvage therapies. Recently, CD7-targeting chimeric antigen receptor (CAR)-T therapies show efficacy in patients with r/r T-ALL, but relapse with CD7 loss is common. This study evaluates a CD5-gene-edited CAR-T cell therapy targeting CD5 in 19 r/r T-ALL patients, most of whom had previously failed CD7 CAR-T interventions. CAR-T products were derived from previous transplant donors (Cohort A) or newly matched donors (Cohort B). Primary endpoints were dose-limiting toxicity at 21 days and adverse events within 30 days. Secondary endpoints were responses, pharmacokinetics and severe adverse events after 30 days. A total of 16 received infusions, 10 at target dose of 1 × 106 kg-1. All encountered grade 3-4 cytopenias and one had a grade 3 infection within 30 days. All patients (100%) achieved complete remission or complete remission with incomplete blood count recovery by day 30. At a median follow-up of 14.3 months, four received transplantation; three were in remission and one died of infection. Of 12 untransplanted patients, 2 were in remission, 3 relapsed, 5 died of infection and 2 of thrombotic microangiopathy. CAR-T cells persisted and cleared CD5+ T cells. CD5- T cells, mostly CD5-gene-edited, increased but remained below normal levels. These results suggest this CD5-specific CAR-T intervention has a high remission rate for T-ALL patients. Evidence also suggests the risk of late-onset severe infection may be mitigated with consolidative transplantation. This study provides insights that could help to optimize this promising intervention. ClinicalTrials.gov registration: NCT05032599 .

6.
J Environ Manage ; 370: 122460, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39288498

RESUMO

China has explicitly prioritized the enhancement of ecosystem quality and stability(EQS) as a governmental objective. However, our understanding of systematic and comprehensive assessment methods for EQS remains limited. The development and investigation of corresponding evaluation frameworks and their underlying mechanisms remain insufficiently explored. This study employs the concept of an "ideal reference system and key indicators," integrating diverse ecosystem and human activity characteristics from perspectives such as ecosystem structure, function, and landscape vulnerability, to determine indicator weights using the Analytic Hierarchy Process(AHP) and entropy weight method, thereby constructing an evaluation framework for assessing the quality and stability of the Qinghai-Tibet Plateau(QTP) ecosystem. The spatiotemporal variations in EQS from 2000 to 2018 were examined, and the key driving factors were identified using the optimal parameter-based geographical detector (OPGD). The results indicate that the EQS of the QTP exhibit a spatial distribution pattern characterized by higher values in the southeast and lower values in the northwest. From 2000 to 2018, there has been a consistent improvement in the overall ecosystem quality and stability across the QTP. The EQS exhibit a significant synergistic effect, with high-high(26.59 ± 1.26%) and low-low(32.61 ± 1.45%) matching combinations becoming the predominant regional patterns. However, in climatic transition zones and glacial areas, the relationship between these factors is particularly distinctive, indicating ecosystem response mechanisms specific to certain natural environmental conditions. Vegetation cover(>0.697), evapotranspiration(>0.620), and precipitation(>0.688) are the primary natural factors influencing EQS, while the impact of human activities has become increasingly significant. Furthermore, the research findings underscore the positive effects of the variable climatic conditions of the QTP on ecosystems within the context of global climate warming, while the stringent implementation of ecological protection measures has collectively contributed to the enhancement of EQS. The proposed evaluation framework not only facilitates a comprehensive and precise assessment of regional EQS, but also provides a scientific basis for understanding and managing the adaptive responses of plateau ecosystems under the complex interplay of natural and anthropogenic factors.

7.
J Zhejiang Univ Sci B ; : 1-7, 2024 Sep 26.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-39327259

RESUMO

Oligodendrocytes are the myelinating cells of the central nervous system. Brain injury and neurodegenerative disease often lead to oligodendrocyte death and subsequent demyelination-related pathological changes, resulting in neurological defects and cognitive impairment (Spaas et al., 2021; Zhang J et al., 2022). Multiple sclerosis (MS) is a major demyelinating disease of the central nervous system. The pathology of MS is characterized by the loss of myelin, oligodendrocytes, and axons in the brain, brain stem, and spinal cord, as well as by white matter lesions (Lassmann et al., 2007). Unfortunately, no definitive cure for MS has been developed. Immunomodulatory and anti-inflammatory drugs are effective in the relapsing-remitting phase of MS because they reduce the frequency of relapses and the formation of inflammatory lesions; however, they do not alter the course of progressive MS and are insufficient to cure chronic neurological dysfunction (Xiao et al., 2015; Zhang et al., 2021). The treatment outcome is even worse for MS patients with primary and secondary progressions. Mesenchymal stem cells (MSCs) are stromal cells that can self-renew and exhibit multilineage differentiation. MSCs are easy to expand in vitro and exhibit low immunogenicity, no tumorigenic risks, and ethical controversies, making them a promising candidate for regenerative medicine (Zhang L et al., 2022; Xu et al., 2023). Many studies have confirmed the neural differentiation potential of MSCs under certain conditions, making them a prime candidate for treating neurodegenerative diseases (Jang et al., 2010; Yan et al., 2013). The present study investigated the effects of cranial bone-marrow mesenchymal stem cells (cBMMSCs) and oligodendrocyte-specific protein 2-positive (Olig2+) single-colony-derived cBMMSC (sc-cBMMSC), isolated in our previous work (Yang et al., 2022), in a central nervous system demyelination mouse model.

8.
Chem Sci ; 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39296995

RESUMO

Visible-light-driven direct asymmetric α-C(sp3)-H bond functionalization of glycinate provides a direct and efficient route for the synthesis of diverse optically enriched α-amino acid derivatives. However, asymmetric coupling between glycinate radical species and ketones faces significant challenges, including competitive pathways, mutable intermediates, as well as congested stereogenic centers. Herein, we disclose the first example for the asymmetric photocatalytic synthesis of a diverse array of ß-diaryl-ß-hydroxy-α-amino acetate derivatives from glycinates and heteroaryl ketones through the synergistic catalysis of achiral iridium photoredox catalyst and chiral lanthanide Lewis acid catalysts. The enantioselective radical addition pathway is supported by spectroscopic experiments, control experiments and DFT calculations.

9.
Mol Ther ; 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39244642

RESUMO

Chimeric antigen receptor (CAR)-T cell therapy showed preliminary activity in patients with refractory or relapsed T cell acute lymphoblastic leukemia (r/r T-ALL). However, many obstacles remain, including manufacturing difficulties and risk of infections. This phase I study (NCT04840875) evaluated autologous CD7 CAR-T cells manufactured without pre-selection of healthy T cells in r/r T-ALL. Thirty patients (29 children and one adult) with a median of two lines of prior therapy but without detectable peripheral leukemia were enrolled. Excluding three cases of manufacturing failures, a total of 27 (90%) patients received infusions after products were confirmed free of leukemia contamination, including 16 (59%) meeting planned target doses. Common adverse events within 30 days included grade 3-4 cytopenias (100%), grade 1-2 (70%) and 3-4 (7%, including one dose-limiting toxicity) cytokine release syndrome, grade 1 neurotoxicity (7%), grade 2 infection (4%), and grade 2 graft-versus-host disease (4%). Two patients developed grade 2 infections after day 30. At day 30, 96% responded and 85% achieved complete remission (CR) or CR with incomplete hematologic recovery (CRi). Seventy-four percent underwent transplantation. Twelve-month progression-free survival with and without censoring transplantation was 22% (95% confidence interval 4%-100%) and 57% (41%-81%), respectively. These results support that autologous CD7 CAR-T therapy without T cell pre-selection is feasible in patients with r/r T-ALL.

10.
Langmuir ; 40(37): 19885-19895, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39225360

RESUMO

Fog collection effectively alleviates the current freshwater shortage; thus, enhancing its efficiency is crucial. Here, we report a novel bionic fog collection surface (Al@B-V) comprising composite superhydrophobic bumps integrated with superhydrophilic V-channel grooves. This surface, which has efficient fog nucleation points and enhanced water transport capabilities, effectively balances fog capture and water transport during the collection process, thereby achieving high-efficiency fog collection. Compared to ordinary aluminum-based surfaces, Al@B-V achieves a fog collection efficiency of up to 3.08 g·cm-2·h-1, three times higher than the original aluminum-based surface. Furthermore, the V-channel groove proposed in this study exhibits a water transport speed of up to 165 mm·s-1, which is remarkably approximately 80 times faster than the commonly used U-channel groove. Additionally, this V-channel groove can overcome gravity, transporting approximately 10 µL of liquid to the top even when placed at 90° inclination. It can directionally transport 10 µL of liquid over a distance of up to 151 mm on a plane. This novel microgroove design can be effectively applied in various fields, including liquid collection, directional transport, seawater desalination, microfluidics, and drug delivery.

11.
Chem Commun (Camb) ; 60(78): 10926-10929, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39258335

RESUMO

Asymmetric synthesis of 3-(3-indolomethyl)oxindoles through the addition of indole-substituted enolized ketoesters to 3-bromo-3-substituted oxindoles has been achieved using a N,N'-dioxide/Ho(III) complex. A number of 3-(3-indolomethyl)oxindoles, which may possess biological activity, were obtained in good yields with high diastereo- and enantioselectivities (up to 97% yield, >19 : 1 dr, 98% ee). Furthermore, time-dependent reversal of diastereoselectivity enabled access to optically active diastereomers. The product followed by facile transformations gave a new route into trigolute analogs.

12.
Angew Chem Int Ed Engl ; : e202414712, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39226119

RESUMO

The asymmetric rearrangement of allylic sulfilimines is an effective route to synthetic attractive targets such as allylic sulfenamides and others. The current methods are limited to chirality transfer from chiral allylic sulfilimine precursors. Herein, we report a general and fundamentally new rearrangement route accessing optically enriched allylic sulfenamides and their derivatives. The process involves a S-alkylation and an unusual S-to-N rearrangement step. The chiral nickel complex enables the transformation of a broad scope of sulfenamides and vinyl α-diazo pyrazoleamides under mild conditions. Various allylic sulfenamides have been synthesized with excellent γ-regioselectivity and enantioselectivity, which can be efficiently converted to sulfinamide and 4-aminobutenoic acid derivatives. In addition, DFT calculations demonstrate the connection between the spin state and conformation of nickel vinyl carbenoid, as well as an unknown rearrangement process.

13.
J Environ Manage ; 368: 122197, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39142106

RESUMO

Agricultural production and sustainable human livelihoods in large river basins are threatened by climate change, human activities, and resource constraints. However, due to the complexity of socio-ecological interactions and agricultural sustainability, current studies are still limited by a priori knowledge and systematic analyses, as well as by the lack of quantification and identification of key factors and valuable pathway structures for agricultural production activities. Here, we combined observation-based causal inference and network analysis to quantify and assess the complex interactions in agricultural production in the Yellow River Basin (YRB) based on data from 12 factors relevant to agriculture over 40 years. We quantitatively assessed the leveraging and hindering roles of the factors in the interacting network system and provided managers with optimization priorities and possible causal pathways to achieve sustainable agriculture in the basin. For example, the fruit yield and income of rural households were identified as leveraging factors that positively affect the agricultural economy. Groundwater was seen as a hindering factor in dampening the negative impacts of the system, highlighting the importance of preventing groundwater depletion. Moreover, the findings suggest that spatially diverse causal interaction structures exist in the YRB and have shaped a variety of distinctive agricultural development modes. Our research ideas and results highlight both systemic considerations and the amplifying or dampening role of factors in interaction pathways, providing valuable quantitative insights into the management and intervention of sustainable agriculture in large river basins. Owing to replaceable and extensible network models, the methodology has the potential to be utilized in a variety of study areas and topics with complex socio-ecological interactions.


Assuntos
Agricultura , Rios , Humanos , Mudança Climática , Conservação dos Recursos Naturais , Água Subterrânea
14.
Chem Sci ; 15(33): 13299-13305, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39183897

RESUMO

A bimetallic relay catalysis protocol for tandem allylic C-H amination and asymmetric [2,3]-sigmatropic rearrangement has been developed with the use of an achiral Pd0 catalyst and a chiral N,N'-dioxide-MgII complex in a one-pot operation. A series of anti-α-amino derivatives containing two stereogenic centers were prepared from readily available allylbenzenes and glycine pyrazolamide with good yields and high stereoselectivities. Moreover, the synthetic potential of this protocol was further demonstrated by the product transformations, and a catalytic cycle was proposed to illustrate the reaction process.

15.
J Med Chem ; 67(17): 15873-15891, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39159426

RESUMO

Caspase-1 plays a central role in innate immunity, as its activation by inflammasomes induces the production of proinflammatory cytokines and pyroptosis. However, specific inhibition of the enzymatic activity of this protease is not effective in suppressing inflammation, owing to its enzyme-independent function. Herein, we identified a cyclohexenyl isothiocyanate compound (CIB-1476) that potently inhibited caspase-1 activity and suppressed the assembly and activation of the NLRP3 inflammasome and gasdermin-D-mediated pyroptosis. Mechanistically, CIB-1476 directly targeted pro-caspase-1 as an irreversible covalent inhibitor by binding to Cys285 and Cys397, resulting in more durable anti-inflammatory effects in the suppression of enzyme-dependent IL-1ß production and enzyme-independent nuclear factor κB activation. Chemoproteomic profiling demonstrated the engagement of CIB-1476 with caspase-1. CIB-1476 showed potent therapeutic effects by suppressing inflammasome activation in mice, which was abolished in Casp1-/- mice. These results warrant further development of CIB-1476 along with its analogues as a novel strategy for caspase-1 inhibitors.


Assuntos
Caspase 1 , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Piroptose , Piroptose/efeitos dos fármacos , Caspase 1/metabolismo , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Inflamassomos/metabolismo , Camundongos , Humanos , Camundongos Endogâmicos C57BL , Inibidores de Caspase/farmacologia , Inibidores de Caspase/química , Isotiocianatos/farmacologia , Isotiocianatos/química , Camundongos Knockout , Descoberta de Drogas
16.
Chem Sci ; 15(32): 13111, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39148772

RESUMO

[This corrects the article DOI: 10.1039/D4SC02201G.].

17.
J Environ Manage ; 367: 122071, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39098077

RESUMO

As research on the full spectrum of ecosystem service (ES) generation and utilization within coupled human and natural systems (CHANS) has expanded, many studies have shown that the spatiotemporal dynamics of ESs are managed and influenced by human activities. However, there is insufficient research on how ESs are affected by bidirectional coupling between societal and ecological factors during spatial flow, particularly in terms of cross-scale impacts. These bidirectional influences between humans and nature are closely related to the utilization and transfer of ESs and affect the perception of spatiotemporal patterns of ESs and the formulation of management strategies. To fill this research gap, this study focuses on the Yellow River Basin (YRB), using network models to track the spatial dynamics of ES flows (ESFs) and the interactions between ecosystems and socio-economic systems within the basin on an annual scale from 2000 to 2020. The results highlight cross-scale impacts and feedback processes between local subbasins and the larger regional basin: As the supply-demand ratios of freshwater ESs, soil conservation ESs, and food ESs increase within individual subbasins of the YRB, more surplus ESs flow among subbasins. This not only alleviates spatial mismatches in ES supply and demand across the entire basin but also enhances the connectivity of the basin's ESF network. Subsequently, the cascading transfer and accumulation of ESs feedback into local socio-ecological interactions, with both socio-economic factors and the capacity for ES output within subbasins becoming increasingly reliant on external ES inflows. These results underscore the crucial role of ESFs within the CHANS of the YRB and imply the importance of cross-regional cooperation and cross-scale management strategies in optimizing ES supply-demand relationships. Furthermore, this study identifies the potential risks and challenges inherent in highly coupled systems. In conclusion, this work deepens the understanding of the spatial flow characteristics of ESs and their socio-ecological interactions; the analytical methods used in this study can also be applied to research on large river basins like the YRB, and even larger regional ecosystems.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Rios , Humanos , Ecologia
18.
Nat Commun ; 15(1): 6155, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039086

RESUMO

Chimeric antigen receptor (CAR) T cells show suboptimal efficacy in acute myeloid leukemia (AML). We find that CAR T cells exposed to myeloid leukemia show impaired activation and cytolytic function, accompanied by impaired antigen receptor downstream calcium, ZAP70, ERK, and C-JUN signaling, compared to those exposed to B-cell leukemia. These defects are caused in part by the high expression of CD155 by AML. Overexpressing C-JUN, but not other antigen receptor downstream components, maximally restores anti-tumor function. C-JUN overexpression increases costimulatory molecules and cytokines through reinvigoration of ERK or transcriptional activation, independent of anti-exhaustion. We conduct an open-label, non-randomized, single-arm, phase I trial of C-JUN-overexpressing CAR-T in AML (NCT04835519) with safety and efficacy as primary and secondary endpoints, respectively. Of the four patients treated, one has grade 4 (dose-limiting toxicity) and three have grade 1-2 cytokine release syndrome. Two patients have no detectable bone marrow blasts and one patient has blast reduction after treatment. Thus, overexpressing C-JUN endows CAR-T efficacy in AML.


Assuntos
Imunoterapia Adotiva , Leucemia Mieloide Aguda , Proteínas Proto-Oncogênicas c-jun , Receptores de Antígenos Quiméricos , Humanos , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/genética , Imunoterapia Adotiva/métodos , Pessoa de Meia-Idade , Masculino , Feminino , Proteínas Proto-Oncogênicas c-jun/metabolismo , Animais , Linfócitos T/imunologia , Linfócitos T/metabolismo , Idoso , Adulto , Linhagem Celular Tumoral , Camundongos
19.
Chem Commun (Camb) ; 60(58): 7507-7510, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38949684

RESUMO

A catalytic asymmetric dearomatization reaction of benzyl 1-naphthyl ethers accelerated by a chiral N,N'-dioxide/Co(II) complex is disclosed. The reaction proceeds via an enantioselective [1,3] O-to-C rearrangement through a tight ion-pair pathway, providing a wide array of α-naphthalenone derivatives bearing an all-carbon quaternary center in high yields with excellent ee values.

20.
Chem Sci ; 15(28): 11005-11012, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39027306

RESUMO

A highly efficient asymmetric [1,3]- and [3,3]-O-to-C sigmatropic rearrangement of 3-allyloxy-4H-chromenones and their analogues was developed. Chiral N,N'-dioxide complexes of 3d late transition metal complexes enabled two mechanistically different processes, giving a series of optically active 2,2-disubstituted chromane-3,4-diones and 2-allyl-3-hydroxy-4H-chromen-4-ones as well as their related compounds in excellent yield and enantioselectivity. Systemic mechanistic studies and DFT calculation revealed the nature of the vinyl ether unit of the substrate, which biased regioselectivity via a stepwise tight ion pair pathway and a concerted pericyclic pathway, respectively. The enantioselectivity of the two processes is also disclosed.

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