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1.
Genome Res ; 33(10): 1690-1707, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37884341

RESUMO

The rumen undergoes developmental changes during maturation. To characterize this understudied dynamic process, we profiled single-cell transcriptomes of about 308,000 cells from the rumen tissues of sheep and goats at 17 time points. We built comprehensive transcriptome and metagenome atlases from early embryonic to rumination stages, and recapitulated histomorphometric and transcriptional features of the rumen, revealing key transitional signatures associated with the development of ruminal cells, microbiota, and core transcriptional regulatory networks. In addition, we identified and validated potential cross-talk between host cells and microbiomes and revealed their roles in modulating the spatiotemporal expression of key genes in ruminal cells. Cross-species analyses revealed convergent developmental patterns of cellular heterogeneity, gene expression, and cell-cell and microbiome-cell interactions. Finally, we uncovered how the interactions can act upon the symbiotic rumen system to modify the processes of fermentation, fiber digestion, and immune defense. These results significantly enhance understanding of the genetic basis of the unique roles of rumen.


Assuntos
Metagenoma , Microbiota , Ovinos/genética , Animais , Transcriptoma , Rúmen , Ruminantes/genética
2.
Nature ; 579(7800): 598-602, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32028527

RESUMO

The anti-cancer drug target poly(ADP-ribose) polymerase 1 (PARP1) and its close homologue, PARP2, are early responders to DNA damage in human cells1,2. After binding to genomic lesions, these enzymes use NAD+ to modify numerous proteins with mono- and poly(ADP-ribose) signals that are important for the subsequent decompaction of chromatin and the recruitment of repair factors3,4. These post-translational modifications are predominantly serine-linked and require the accessory factor HPF1, which is specific for the DNA damage response and switches the amino acid specificity of PARP1 and PARP2 from aspartate or glutamate to serine residues5-10. Here we report a co-structure of HPF1 bound to the catalytic domain of PARP2 that, in combination with NMR and biochemical data, reveals a composite active site formed by residues from HPF1 and PARP1 or PARP2 . The assembly of this catalytic centre is essential for the addition of ADP-ribose moieties after DNA damage in human cells. In response to DNA damage and occupancy of the NAD+-binding site, the interaction of HPF1 with PARP1 or PARP2 is enhanced by allosteric networks that operate within the PARP proteins, providing an additional level of regulation in the induction of the DNA damage response. As HPF1 forms a joint active site with PARP1 or PARP2, our data implicate HPF1 as an important determinant of the response to clinical PARP inhibitors.


Assuntos
ADP-Ribosilação , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Dano ao DNA , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Poli(ADP-Ribose) Polimerase-1/química , Poli(ADP-Ribose) Polimerase-1/metabolismo , Poli(ADP-Ribose) Polimerases/química , Poli(ADP-Ribose) Polimerases/metabolismo , Regulação Alostérica , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Biocatálise , Proteínas de Transporte/genética , Domínio Catalítico , Células HEK293 , Humanos , Modelos Moleculares , Mutação , NAD/metabolismo , Ressonância Magnética Nuclear Biomolecular , Proteínas Nucleares/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Anêmonas-do-Mar
3.
Mol Biol Evol ; 41(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38267085

RESUMO

Cellular and physiological cycles are driven by endogenous pacemakers, the diurnal and circadian rhythms. Key functions such as cell cycle progression and cellular metabolism are under rhythmic regulation, thereby maintaining physiological homeostasis. The photoreceptors phytochrome and cryptochrome, in response to light cues, are central input pathways for physiological cycles in most photosynthetic organisms. However, among Archaeplastida, red algae are the only taxa that lack phytochromes. Current knowledge about oscillatory rhythms is primarily derived from model species such as Arabidopsis thaliana and Chlamydomonas reinhardtii in the Viridiplantae, whereas little is known about these processes in other clades of the Archaeplastida, such as the red algae (Rhodophyta). We used genome-wide expression profiling of the red seaweed Gracilariopsis chorda and identified 3,098 rhythmic genes. Here, we characterized possible cryptochrome-based regulation and photosynthetic/cytosolic carbon metabolism in this species. We found a large family of cryptochrome genes in G. chorda that display rhythmic expression over the diurnal cycle and may compensate for the lack of phytochromes in this species. The input pathway gates regulatory networks of carbon metabolism which results in a compact and efficient energy metabolism during daylight hours. The system in G. chorda is distinct from energy metabolism in most plants, which activates in the dark. The green lineage, in particular, land plants, balance water loss and CO2 capture in terrestrial environments. In contrast, red seaweeds maintain a reduced set of photoreceptors and a compact cytosolic carbon metabolism to thrive in the harsh abiotic conditions typical of intertidal zones.


Assuntos
Arabidopsis , Rodófitas , Alga Marinha , Alga Marinha/genética , Criptocromos/metabolismo , Rodófitas/genética , Ritmo Circadiano/genética , Arabidopsis/genética
4.
Genome Res ; 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35948368

RESUMO

Understanding the genetic mechanisms of phenotypic variation in hybrids between domestic animals and their wild relatives may aid germplasm innovation. Here, we report the high-quality genome assemblies of a male Pamir argali (O ammon polii, 2n = 56), a female Tibetan sheep (O aries, 2n = 54), and a male hybrid of Pamir argali and domestic sheep, and the high-throughput sequencing of 425 ovine animals, including the hybrids of argali and domestic sheep. We detected genomic synteny between Chromosome 2 of sheep and two acrocentric chromosomes of argali. We revealed consistent satellite repeats around the chromosome breakpoints, which could have resulted in chromosome fusion. We observed many more hybrids with karyotype 2n = 54 than with 2n = 55, which could be explained by the selfish centromeres, the possible decreased rate of normal/balanced sperm, and the increased incidence of early pregnancy loss in the aneuploid ewes or rams. We identified genes and variants associated with important morphological and production traits (e.g., body weight, cannon circumference, hip height, and tail length) that show significant variations. We revealed a strong selective signature at the mutation (c.334C > A, p.G112W) in TBXT and confirmed its association with tail length among sheep populations of wide geographic and genetic origins. We produced an intercross population of 110 F2 offspring with varied number of vertebrae and validated the causal mutation by whole-genome association analysis. We verified its function using CRISPR-Cas9 genome editing. Our results provide insights into chromosomal speciation and phenotypic evolution and a foundation of genetic variants for the breeding of sheep and other animals.

5.
Plant Physiol ; 196(1): 564-578, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38753299

RESUMO

The transcriptional regulation of aluminum (Al) tolerance in plants is largely unknown, although Al toxicity restricts agricultural yields in acidic soils. Here, we identified a NAM, ATAF1/2, and cup-shaped cotyledon 2 (NAC) transcription factor that participates in Al tolerance in Arabidopsis (Arabidopsis thaliana). Al substantially induced the transcript and protein levels of ANAC070, and loss-of-function mutants showed remarkably increased Al sensitivity, implying a beneficial role of ANAC070 in plant tolerance to Al toxicity. Further investigation revealed that more Al accumulated in the roots of anac070 mutants, especially in root cell walls, accompanied by a higher hemicellulose and xyloglucan level, implying a possible interaction between ANAC070 and genes that encode proteins responsible for the modification of xyloglucan, including xyloglucan endo-transglycosylase/hydrolase (XTH) or ANAC017. Yeast 1-hybrid analysis revealed a potential interaction between ANAC070 and ANAC017, but not for other XTHs. Furthermore, dual-luciferase reporter assay, RT-qPCR, and GUS analysis revealed that ANAC070 could directly repress the transcript levels of ANAC017, and knockout of ANAC017 in the anac070 mutant partially restored its Al sensitivity phenotype, indicating that ANAC070 contributes to Al tolerance mechanisms other than suppression of ANAC017 expression. Further analysis revealed that the core transcription factor SENSITIVE TO PROTON RHIZOTOXICITY 1 (STOP1) and its target genes, which control Al tolerance in Arabidopsis, may also be involved in ANAC070-regulated Al tolerance. In summary, we identified a transcription factor, ANAC070, that represses the ANAC017-XTH31 module to regulate Al tolerance in Arabidopsis.


Assuntos
Alumínio , Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Glucanos , Fatores de Transcrição , Xilanos , Alumínio/toxicidade , Arabidopsis/genética , Arabidopsis/efeitos dos fármacos , Arabidopsis/fisiologia , Arabidopsis/metabolismo , Glucanos/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Xilanos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Parede Celular/metabolismo , Parede Celular/efeitos dos fármacos , Parede Celular/genética , Mutação/genética
6.
Methods ; 223: 35-44, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38228195

RESUMO

A highly efficient sensor has been successfully developed using quinoline-based BODIPY compounds (8-quinoline-4,4-difluoro-4-boro-3a, 4a-diazaindacene (C1) and 7-hydroxy-8-quinoline-4,4-difluoro-4-boro-3a, 4a-diazindacene (C2) to detect Hg2+ ions. The sensor C1 exhibits remarkable selectivity in detecting Hg2+ with a limit of detection 3.06 × 10-8 mol/L. The developed chemical sensors have shown stability, cost-effectiveness, ease of preparation, and remarkable selectivity towards Hg2+ ions compared to other commonly occurring metal ions. The total recovery of the sensor C1 can be achieved by using a 0.1 mol/L solution of KI. The proposed sensor C1 has been applied to determine Hg2+ in tap and distilled water, yielding excellent results. In addition, the binding mode of C1-Hg2+ and C2-Hg2+ complexes was a 1:1 ratio confirmed by mass spectra, Job's plot, and DFT study. Moreover, the sensor C1 successfully applied for the biological studies results in negligible cytotoxicity, which demonstrates it can be used to determine Hg2+ in HT22 cells.


Assuntos
Compostos de Boro , Mercúrio , Quinolinas , Corantes , Íons
7.
Nature ; 574(7780): 722-725, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31645759

RESUMO

The enzyme protochlorophyllide oxidoreductase (POR) catalyses a light-dependent step in chlorophyll biosynthesis that is essential to photosynthesis and, ultimately, all life on Earth1-3. POR, which is one of three known light-dependent enzymes4,5, catalyses reduction of the photosensitizer and substrate protochlorophyllide to form the pigment chlorophyllide. Despite its biological importance, the structural basis for POR photocatalysis has remained unknown. Here we report crystal structures of cyanobacterial PORs from Thermosynechococcus elongatus and Synechocystis sp. in their free forms, and in complex with the nicotinamide coenzyme. Our structural models and simulations of the ternary protochlorophyllide-NADPH-POR complex identify multiple interactions in the POR active site that are important for protochlorophyllide binding, photosensitization and photochemical conversion to chlorophyllide. We demonstrate the importance of active-site architecture and protochlorophyllide structure in driving POR photochemistry in experiments using POR variants and protochlorophyllide analogues. These studies reveal how the POR active site facilitates light-driven reduction of protochlorophyllide by localized hydride transfer from NADPH and long-range proton transfer along structurally defined proton-transfer pathways.


Assuntos
Clorofila/biossíntese , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/química , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Synechococcus/enzimologia , Synechocystis/enzimologia , Catálise , Clorofila/química , Estrutura Molecular , Fotoquímica , Protoclorifilida/metabolismo , Relação Estrutura-Atividade , Especificidade por Substrato
8.
Nucleic Acids Res ; 51(15): 8217-8236, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37326024

RESUMO

AlphaFold2 and related computational tools have greatly aided studies of structural biology through their ability to accurately predict protein structures. In the present work, we explored AF2 structural models of the 17 canonical members of the human PARP protein family and supplemented this analysis with new experiments and an overview of recent published data. PARP proteins are typically involved in the modification of proteins and nucleic acids through mono or poly(ADP-ribosyl)ation, but this function can be modulated by the presence of various auxiliary protein domains. Our analysis provides a comprehensive view of the structured domains and long intrinsically disordered regions within human PARPs, offering a revised basis for understanding the function of these proteins. Among other functional insights, the study provides a model of PARP1 domain dynamics in the DNA-free and DNA-bound states and enhances the connection between ADP-ribosylation and RNA biology and between ADP-ribosylation and ubiquitin-like modifications by predicting putative RNA-binding domains and E2-related RWD domains in certain PARPs. In line with the bioinformatic analysis, we demonstrate for the first time PARP14's RNA-binding capability and RNA ADP-ribosylation activity in vitro. While our insights align with existing experimental data and are probably accurate, they need further validation through experiments.


Assuntos
Inibidores de Poli(ADP-Ribose) Polimerases , Poli(ADP-Ribose) Polimerases , Humanos , Poli(ADP-Ribose) Polimerases/metabolismo , Domínios Proteicos , ADP-Ribosilação , RNA/metabolismo
9.
Nano Lett ; 24(31): 9583-9590, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39041791

RESUMO

Thanks to their tunable infrared absorption, solution processability, and low fabrication costs, HgTe colloidal quantum dots (CQDs) are promising for optoelectronic devices. Despite advancements in device design, their potential for imaging applications remains underexplored. For integration with Si-based readout integrated circuits (ROICs), top illumination is necessary for simultaneous light absorption and signal acquisition. However, most high-performing traditional HgTe CQD photodiodes are p-on-n stack and bottom-illuminated. Herein, we report top-illuminated inverted n-on-p HgTe CQD photodiodes using a robust p-type CQD layer and a thermally evaporated Bi2S3 electron transport layer. The p-type CQD solid is achieved by exploring the synergism in binary HgTe and Ag2Te CQDs. These photodetectors show a room-temperature detectivity of 3.4 × 1011 jones and an EQE of ∼44% at ∼1.7 µm wavelength, comparable to the p-on-n HgTe CQD photodiodes. A top-illuminated HgTe CQD short-wave infrared imager (640 × 512 pixels) was fabricated, demonstrating successful infrared imaging.

10.
J Cell Mol Med ; 28(7): e18221, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38509759

RESUMO

Gliomas are the most common tumours in the central nervous system. In the present study, we aimed to find a promising anti-glioma compound and investigate the underlying molecular mechanism. Glioma cells were subjected to the 50 candidate compounds at a final concentration of 10 µM for 72 h, and CCK-8 was used to evaluate their cytotoxicity. NPS-2143, an antagonist of calcium-sensing receptor (CASR), was selected for further study due to its potent cytotoxicity to glioma cells. Our results showed that NPS-2143 could inhibit the proliferation of glioma cells and induce G1 phase cell cycle arrest. Meanwhile, NPS-2143 could induce glioma cell apoptosis by increasing the caspase-3/6/9 activity. NPS-2143 impaired the immigration and invasion ability of glioma cells by regulating the epithelial-mesenchymal transition process. Mechanically, NPS-2143 could inhibit autophagy by mediating the AKT-mTOR pathway. Bioinformatic analysis showed that the prognosis of glioma patients with low expression of CASR mRNA was better than those with high expression of CASR mRNA. Gene set enrichment analysis showed that CASR was associated with cell adhesion molecules and lysosomes in glioma. The nude mice xenograft model showed NPS-2143 could suppress glioma growth in vivo. In conclusion, NPS-2143 can suppress the glioma progression by inhibiting autophagy.


Assuntos
Glioma , Naftalenos , Proteínas Proto-Oncogênicas c-akt , Animais , Humanos , Camundongos , Apoptose , Autofagia , Linhagem Celular Tumoral , Proliferação de Células , Glioma/tratamento farmacológico , Glioma/genética , Glioma/metabolismo , Camundongos Nus , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , Serina-Treonina Quinases TOR/metabolismo , Naftalenos/farmacologia
11.
Plant J ; 115(6): 1500-1513, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37313760

RESUMO

Understanding how different driving forces have promoted biological divergence and speciation is one of the central issues in evolutionary biology. The Triticum/Aegilops species complex contains 13 diploid species belonging to the A-, B- and D-lineages and offers an ideal system to address the evolutionary dynamics of lineage fusion and splitting. Here, we sequenced the whole genomes of one S-genome species (Aegilops speltoides) of the B-lineage and four S*-genome diploid species (Aegilops bicornis, Aegilops longissima, Aegilops sharonensis and Aegilops searsii) of the D-lineage at the population level. We performed detailed comparisons of the five species and with the other four representative A-, B- and D-lineage species. Our estimates identified frequent genetic introgressions from A- and B-lineages to the D-lineage species. A remarkable observation is the contrasting distributions of putative introgressed loci by the A- and B-lineages along all the seven chromosomes to the extant D-lineage species. These genetic introgressions resulted in high levels of genetic divergence at centromeric regions between Ae. speltoides (B-lineage) and the other four S*-genome diploid species (D-lineage), while natural selection is a potential contributor to divergence among the four S*-genome species at telomeric regions. Our study provides a genome-wide view on how genetic introgression and natural selection acted together yet chromosome-regionally divided to promote genomic divergence among the five S- and S*-genome diploid species, which provides new and nuanced insights into the evolutionary history of the Triticum/Aegilops species complex.


Assuntos
Aegilops , Aegilops/genética , Filogenia , Triticum/genética , Diploide , Genoma de Planta/genética , Genômica , Seleção Genética
12.
BMC Genomics ; 25(1): 292, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504154

RESUMO

BACKGROUND: Dystrophinopathies are the most common X-linked inherited muscle diseases, and the disease-causing gene is DMD. Exonic duplications are a common type of pathogenic variants in the DMD gene, however, 5' end exonic duplications containing exon 1 are less common. When assessing the pathogenicity of exonic duplications in the DMD gene, consideration must be given to their impact on the reading frame. Traditional molecular methods, such as multiplex ligation-dependent probe amplification (MLPA) and next-generation sequencing (NGS), are commonly used in clinics. However, they cannot discriminate the precise physical locations of breakpoints and structural features of genomic rearrangement. Long-read sequencing (LRS) can effectively overcome this limitation. RESULTS: We used LRS technology to perform whole genome sequencing on three families and analyze the structural variations of the DMD gene, which involves the duplications of exon 1 and/or exon 2. Two distinct variant types encompassing exon 1 in the DMD Dp427m isoform and/or Dp427c isoform are identified, which have been infrequently reported previously. In pedigree 1, the male individuals harboring duplication variant of consecutive exons 1-2 in the DMD canonical transcript (Dp427m) and exon 1 in the Dp427c transcript are normal, indicating the variant is likely benign. In pedigree 3, the patient carries complex SVs involving exon 1 of the DMD Dp427c transcript showing an obvious phenotype. The locations of the breakpoints and the characteristics of structural variants (SVs) are identified by LRS, enabling the classification of the variants' pathogenicity. CONCLUSIONS: Our research sheds light on the complexity of DMD variants encompassing Dp427c/Dp427m promoter regions and emphasizes the importance of cautious interpretation when assessing the pathogenicity of DMD 5' end exonic duplications, particularly in carrier screening scenarios without an affected proband.


Assuntos
Distrofia Muscular de Duchenne , Humanos , Masculino , Distrofina/genética , Éxons , Genômica , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/diagnóstico , Isoformas de Proteínas/genética
13.
J Am Chem Soc ; 146(11): 7594-7604, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38462726

RESUMO

The preservation of chirality during a transformation process, known as the "chiral memory" effect, has garnered significant attention across multiple research disciplines. Here, we first report the retention of the original chiral structure during dynamic covalent chemistry (DCC)-induced structural transformation from porous organic cages into covalent organic frameworks (COFs). A total of six two-dimensional chiral COFs constructed by entirely achiral building blocks were obtained through the DCC-induced substitution of chiral linkers in a homochiral cage (CC3-R or -S) using achiral amine monomers. Homochirality of these COFs resulted from the construction of 3-fold-symmetric benzene-1,3,5-methanimine cores with a propeller-like configuration of one single-handedness throughout the cage-to-COF transformation. The obtained chiral COFs can be further utilized as fluorescence sensors or chiral stationary phases for gas chromatography with high enantioselectivity. The present study thus highlighted the great potential to expand the scope of functional chiral materials via DCC-induced crystal-to-crystal transformation with the chiral memory effect.

14.
J Am Chem Soc ; 146(1): 695-706, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38150351

RESUMO

Ethylene methoxycarbonylation (EMC) to methyl propanoate (MP) is an industrially important reaction and commercially uses a homogeneous Pd-phosphine organometallic complex as the catalyst and corrosive strong acid as the promoter. In this work, we develop a Pt1/MoS2 heterogeneous single-atom catalyst (SAC) which exhibits high activity, selectivity, and good recyclability for EMC reaction without need of any liquid acid. The production rate of MP achieves 0.35 gMP gcat-1 h-1 with MP selectivity of 91.1% at 1 MPa CO, 1 MPa C2H4, and 160 °C, which can be doubled at 2 MPa CO and corresponds to 320.1 molMP molPt-1 h-1, at least 1 order of magnitude higher than the earlier reported heterogeneous catalyst and even comparable to some of homogeneous catalyst. Advanced characterizations and DFT calculations reveal that all the Pt single atoms are located at the Mo vacancies along the Mo edge of the MoS2 nanosheets, forming pocket-like Mo-S-Pt1-S-Mo ensembles with uniform and well-defined structure. Methanol is first adsorbed and dissociated on Mo sites, and the produced H spillovers to the adjacent Pt site forming Pt-H species which then activate ethylene, forming Pt-ethyl species. Meanwhile, CO adsorbed on the other Mo site reacts with the Pt-ethyl species, yielding propionyl species, and this carbonylation is the rate-determining step. The final methoxylation step proceeds via the nucleophilic attack of propionyl species by -OCH3 affording the final product MP. Such a metal-support concerted catalysis enabled by the Mo-S-Pt1-S-Mo multisite ensemble opens a new avenue for SACs to promote the multimolecular reactions that prevail in homogeneous catalysis.

15.
Cancer ; 130(5): 671-682, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-37985356

RESUMO

BACKGROUND: Since reforms were introduced to incentivize drug innovation in 2015, the Chinese pharmaceutical market has experienced unprecedented prosperity, with more new drugs than ever before, especially anticancer treatments. In 2021, Chinese regulatory agencies issued the new guideline for clinical research and development of antitumor drugs, triggering a series of responses on the drug market. Limited research has outlined the nature of the original new drugs in China to understand the dynamic response of the market. METHODS: The objective of this article was to map the clinical development of approved new oncology drugs in China from 2015 to 2021 and differed from previous studies by focusing on original new drugs, using the United States as a benchmark, and elaborating the endogenous features of clinical trials. RESULTS: Clinical trials conducted in China have risen to a level similar to that of the United States in many aspects of trial design, but there is still distance between the implementation and operational details of clinical trials. In the meantime, China has made significant breakthroughs in drug approval. Greater than 60% of novel anticancer drugs in China received accelerated approved for their first listing. Approximately 90% of the pivotal clinical trials supporting initial drug approval used surrogate measures as end points, and one half were nonrandomized or did not have a control group. However, duplicate development without evidence of a clinical advantage compared with current therapies was widely observed. CONCLUSIONS: By presenting a multidimensional landscape of clinical trials and approvals in the real world, this review allows interested researchers, developers, and even regulators to understand what has been done and what should be done next in anticancer drug development in China.


Assuntos
Antineoplásicos , Humanos , Antineoplásicos/uso terapêutico , China , Ensaios Clínicos como Assunto , Aprovação de Drogas
16.
Oncologist ; 29(1): e15-e24, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37279780

RESUMO

BACKGROUND: Neoadjuvant trastuzumab/pertuzumab (HP) plus chemotherapy for HER2-positive breast cancer (BC) achieved promising efficacy. The additional cardiotoxicity still existed. Brecan study evaluated the efficacy and safety of neoadjuvant pegylated liposomal doxorubicin (PLD)/cyclophosphamide and sequential nab-paclitaxel based on HP (PLD/C/HP-nabP/HP). PATIENTS AND METHODS: Brecan was a single-arm phase II study. Eligible patients with stages IIA-IIIC HER2-positive BC received 4 cycles of PLD, cyclophosphamide, and HP, followed by 4 cycles of nab-paclitaxel and HP. Definitive surgery was scheduled after 21 days for patients completing treatment or experiencing intolerable toxicity. The primary endpoint was the pathological complete response (pCR). RESULTS: Between January 2020 and December 2021, 96 patients were enrolled. Ninety-five (99.0%) patients received 8 cycles of neoadjuvant therapy and all underwent surgery with 45 (46.9%) breast-conserving surgery and 51 (53.1%) mastectomy. The pCR was 80.2% (95%CI, 71.2%-87.0%). Four (4.2%) experienced left ventricular insufficiency with an absolute decline in LVEF (43%-49%). No congestive heart failure and ≥grade 3 cardiac toxicity occurred. The objective response rate was 85.4% (95%CI, 77.0%-91.1%), including 57 (59.4%) complete responses and 25 (26.0%) partial responses. The disease control rate was 99.0% (95%CI, 94.3%-99.8%). For overall safety, ≥grade 3 AEs occurred in 30 (31.3%) and mainly included neutropenia (30.2%) and asthenia (8.3%). No treatment-related deaths occurred. Notably, age of >30 (P = .01; OR = 5.086; 95%CI, 1.44-17.965) and HER2 IHC 3+ (P = .02; OR = 4.398; 95%CI, 1.286-15.002) were independent predictors for superior pCR (ClinicalTrials.gov Identifier NCT05346107). CONCLUSION: Brecan study demonstrated the encouraging safety and efficacy of neoadjuvant PLD/C/HP-nabP/HP, suggesting a potential therapeutic option in HER2-positive BC.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Terapia Neoadjuvante/efeitos adversos , Receptor ErbB-2/uso terapêutico , Mastectomia , Resultado do Tratamento , Paclitaxel , Ciclofosfamida/uso terapêutico , Trastuzumab/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
17.
Anal Chem ; 96(43): 17280-17289, 2024 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-39405304

RESUMO

Chiral film-based sensors show great promise for discriminating between enantiomers due to their miniaturization and low power consumption. However, their practical use is hindered by the trade-off between enantioselectivity and mass transfer capability, especially concerning biomacromolecules such as proteins. In this work, we present an effective and straightforward method for creating highly organized macropores within crystalline chiral metal-organic framework (CMOF) films. This approach harnesses the shaping influence of a polystyrene nanosphere template and the crystallization induced by the liquid dielectric barrier discharge plasma. The resultant highly ordered macro-microporous structures improve mass diffusion and access to chiral active sites in the hierarchical CMOF films. Coupled with their inherent chirality, strong fluorescence emission, high crystallinity, and exceptional stability, these attributes endow these CMOF films with enhanced sensing capabilities for chiral molecules. Particularly, the macro-microporous structure facilitates efficient protein recognition, overcoming a significant challenge encountered by MOFs due to protein dimensions surpassing MOF pore sizes. These films exhibit increased enantioselectivity, better limits of detection, and wider linear ranges compared with purely microporous CMOF films. This study thus provides a powerful synthetic approach for hierarchical CMOF films, addressing the limitations of traditional thin film sensors and opening an avenue for efficient chiral sensing of large biomacromolecules.


Assuntos
Estruturas Metalorgânicas , Estereoisomerismo , Porosidade , Estruturas Metalorgânicas/química , Proteínas/química , Proteínas/análise
18.
Immunol Cell Biol ; 102(7): 570-577, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38710590

RESUMO

The γδ T cells are a subpopulation of T cells that are abundantly found in the skin and mucous membranes. Their reactivity to self-antigens and ability to secrete various cytokines make them a key component in psoriasis development. Although the correlation between the immune repertoire (IR) of γδ T-cell receptors and the occurrence and severity of psoriasis remains incompletely explored, high-throughput sequencing of γδ T cells has led to a deeper understanding of IR in psoriasis. This study investigated the differences between γδ T cells in patients with psoriasis and healthy controls. The γδ T cells were identified via immunofluorescence staining and a correlation analysis was performed according to the psoriasis area and severity index (PASI) scores. The IR sequencing method was used to detect IR in the γδ T-cell receptors. The findings demonstrated more skin γδ T cells in patients with psoriasis, which were positively correlated with the PASI score. There were subtle differences in most variable (V), diversity (D) and joining (J) gene segments and VJ/VDJ combination segments between patients with psoriasis and healthy controls. However, a higher diversity of complementarity-determining region 3 (CDR3) was observed in patients with psoriasis. In summary, the IR of skin γδ T cells was significantly altered in patients with psoriasis, and the diversity in the cell's CDR3 population is a promising biomarker for assessment of psoriasis severity.


Assuntos
Regiões Determinantes de Complementaridade , Psoríase , Receptores de Antígenos de Linfócitos T gama-delta , Humanos , Psoríase/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/genética , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Regiões Determinantes de Complementaridade/genética , Pele/imunologia , Pele/patologia , Índice de Gravidade de Doença , Linfócitos T/imunologia , Linfócitos T/metabolismo , Estudos de Casos e Controles
19.
BMC Med ; 22(1): 489, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39443947

RESUMO

BACKGROUND: Previous research has shown that the use of renin-angiotensin system (RAS) blockers is linked to a lower prevalence of posttraumatic stress disorder (PTSD), but longitudinal studies are scarce. We aimed to estimate the association between the use of RAS blockers and the risk of PTSD among individuals taking antihypertensive medications. METHODS: This longitudinal study included participants aged 40-69 from the UK Biobank. Exposure data were obtained from the initial assessment (2006-10), while outcome data were obtained from the online mental health questionnaire administered 6-11 years later (2016-17). We included participants who were under antihypertensive treatment and did not have a prior diagnosis of PTSD before the initial assessment. Use of RAS blockers was defined as self-reported regular use, at the initial assessment, of angiotensin-converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB). Among participants who experienced adverse life experiences, cases of probable PTSD were defined with the six-item PTSD Checklist-Civilian version score ≥ 14. Logistic regression with inverse probability of treatment weighting was used to estimate the odds ratios (ORs) and 95% confidence interval (CI) for the association between RAS blocker use and the risk of probable PTSD. RESULTS: Of the 15,954 participants (mean age = 59.9 years; 42.6% women) under antihypertensive treatment with no prior history of PTSD at the initial assessment, 64.5% were taking RAS blockers. After a mean follow-up of 7.5 years, 1,249 (7.8%) were newly identified with probable PTSD. RAS blocker users had a lower risk of probable PTSD than RAS blocker non-users (OR = 0.84 [95% CI: 0.75-0.94]), whereas the use of other antihypertensive medications showed no such association (users vs. non-users; calcium channel blockers, OR = 0.99 [95% CI: 0.88-1.11]; beta-blockers, 1.20 [1.08-1.34]; and thiazide-related diuretics, 1.15 [1.03-1.29]). The association between probable PTSD risk and the use of ACEi vs. ARB showed no significant difference (p = 0.96). CONCLUSIONS: Among individuals under antihypertensive treatment, the use of RAS blockers was associated with a decreased risk of probable PTSD. This added benefit of RAS blockers should be considered in the selection of antihypertensive medications.


Assuntos
Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Sistema Renina-Angiotensina , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Pessoa de Meia-Idade , Masculino , Feminino , Reino Unido/epidemiologia , Idoso , Antagonistas de Receptores de Angiotensina/efeitos adversos , Antagonistas de Receptores de Angiotensina/uso terapêutico , Estudos Retrospectivos , Adulto , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Estudos Longitudinais , Sistema Renina-Angiotensina/efeitos dos fármacos , Bancos de Espécimes Biológicos , Anti-Hipertensivos/uso terapêutico , Biobanco do Reino Unido
20.
Chembiochem ; : e202400395, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145407

RESUMO

Broadening of signals from atoms at interfaces can often be a limiting factor in applying solution NMR to the structure determination of complexes. Common contributors to such problems include exchange between free and bound states and the increased molecular weight of complexes relative to the free components, but another cause that can be more difficult to deal with occurs when conformational dynamics within the interface takes place at an intermediate rate on the chemical shift timescale. In this work we show how a carefully chosen mutation in the protein HMG-D rescued such a situation, making possible high-resolution structure determination of its complex with a dA2 bulge DNA ligand designed to mimic a natural DNA bend, and thereby revealing a new spatial organization of the complex.

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