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1.
Plant Cell ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635962

RESUMO

Protein S-acylation catalyzed by protein S-acyl transferases (PATs) is a reversible lipid modification regulating protein targeting, stability, and interaction profiles. PATs are encoded by large gene families in plants, and many proteins including receptor-like cytoplasmic kinases (RLCKs) and receptor-like kinases (RLKs) are subject to S-acylation. However, few PATs have been assigned substrates, and few S-acylated proteins have known upstream enzymes. We report that Arabidopsis (Arabidopsis thaliana) class A PATs redundantly mediate pollen tube guidance and participate in the S-acylation of POLLEN RECEPTOR KINASE1 (PRK1) and LOST IN POLLEN TUBE GUIDANCE1 (LIP1), a critical RLK or RLCK for pollen tube guidance, respectively. PAT1, PAT2, PAT3, PAT4, and PAT8, collectively named PENTAPAT for simplicity, are enriched in pollen and show similar subcellular distribution. Functional loss of PENTAPAT reduces seed set due to male gametophytic defects. Specifically, pentapat pollen tubes are compromised in directional growth. We determine that PRK1 and LIP1 interact with PENTAPAT, and their S-acylation is reduced in pentapat pollen. The plasma membrane (PM) association of LIP1 is reduced in pentapat pollen, whereas point mutations reducing PRK1 S-acylation affect its affinity with its interacting proteins. Our results suggest a key role of S-acylation in pollen tube guidance through modulating PM receptor complexes.

2.
Proc Natl Acad Sci U S A ; 121(33): e2402903121, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39102549

RESUMO

Immune checkpoint therapy has limited efficacy for patients with bone-metastatic castration-resistant prostate cancer (bmCRPC). To improve immunotherapy for bmCRPC, we aimed to identify the mechanism of bmCRPC-induced changes in the immune microenvironment. Among bmCRPC patients, higher levels of a 32-gene M2-like macrophage signature in bone metastasis samples correlated with shorter overall survival. Immunohistochemistry showed that CD206-positive (CD206+) macrophages were enriched in bmCRPC bone biopsy specimens compared with primary tumors or lymph node metastases. In preclinical osteogenic prostate cancer (Pca) xenograft models, CD206+ macrophages were recruited to areas with tumor-induced bone. RNA sequencing (RNAseq) analysis showed higher expression of an M2-like gene signature, with activated canonical and noncanonical Wnt pathways, in tumor-associated macrophages isolated from osteogenic tumors (bone-TAMs) than in TAMs isolated from nonosteogenic tumors (ctrl-TAMs). Mechanistic studies showed that endothelial cells (ECs) that had undergone EC-to-osteoblast (EC-to-OSB) transition, the precursors of tumor-induced OSBs, produced paracrine factors, including Wnts, CXCL14, and lysyl oxidase, which induced M2 polarization and recruited M2-like TAMs to the bone-tumor microenvironment (bone-TME). Bone-TAMs suppressed CD8+ T cells' proliferation and cytolytic activity, and these effects were partially reversed by treating bone-TAMs with Wnt inhibitors. Genetic or pharmacological inhibition of Pca-induced EC-to-OSB transition reduced the levels of M2-like macrophages in osteogenic tumors. Our study demonstrates that Pca-induced EC-to-OSB transition drives immunosuppression in the bone-TME, suggesting that therapies that reduce Pca-induced bone formation may improve immunotherapeutic outcomes for bmCRPC.


Assuntos
Neoplasias Ósseas , Células Endoteliais , Macrófagos , Osteoblastos , Microambiente Tumoral , Via de Sinalização Wnt , Masculino , Microambiente Tumoral/imunologia , Humanos , Neoplasias Ósseas/imunologia , Neoplasias Ósseas/secundário , Neoplasias Ósseas/patologia , Neoplasias Ósseas/metabolismo , Animais , Camundongos , Macrófagos/metabolismo , Macrófagos/imunologia , Células Endoteliais/metabolismo , Células Endoteliais/imunologia , Osteoblastos/metabolismo , Osteoblastos/imunologia , Neoplasias de Próstata Resistentes à Castração/imunologia , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Linhagem Celular Tumoral , Neoplasias da Próstata/patologia , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/metabolismo , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/imunologia
3.
Mol Psychiatry ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38361125

RESUMO

Running exercise has been shown to alleviate depressive symptoms. However, the mechanism underlying the antidepressant effects of running exercise is not fully understood. The imbalance of M1/M2 microglia phenotype/polarization and concomitant dysregulation of neuroinflammation play crucial roles in the pathogenesis of depression. Running exercise increases circulating levels of adiponectin which is known to cross the blood‒brain barrier and suppress inflammatory responses. AdipoR1 is an adiponectin receptor that is involved in regulating microglial phenotypes and activation states. However, whether running exercise regulates hippocampal microglial phenotypes and neuroinflammation through adiponectin/AdipoR1 to exert its antidepressant effects remains unclear. In the current study, 4 weeks of running exercise significantly alleviated the depressive-like behaviors of chronic unpredictable stress (CUS)-exposed mice. Moreover, running exercise decreased the microglial numbers and altered microglial morphology in three subregions of the hippocampus to restore the M1/M2 balance; these effects were accompanied by regulation of pro-/anti-inflammatory cytokine production and secretion in CUS-exposed mice. These effects may involve elevation of peripheral tissue (adipose tissue and muscle) and plasma adiponectin levels, and hippocampal AdipoR1 levels as well as activation of the AMPK-NF-κB/STAT3 signaling pathway by running exercise. When an adeno-associated virus was used to knock down hippocampal AdipoR1, mice showed depressive-like behaviors and alterations in microglia and inflammatory factor expression in the hippocampus that were similar to those observed in CUS-exposed mice. Together, these results suggest that running exercise maintains the M1/M2 balance and inhibits neuroinflammation in the hippocampus of CUS-exposed mice. These effects might occur via adiponectin/AdipoR1-mediated activation of the AMPK-NF-κB/STAT3 signaling pathway.

4.
Cell Mol Life Sci ; 81(1): 357, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39158587

RESUMO

SLC30A9 (ZnT9) is a mitochondria-resident zinc transporter. Mutations in SLC30A9 have been reported in human patients with a novel cerebro-renal syndrome. Here, we show that ZnT9 is an evolutionarily highly conserved protein, with many regions extremely preserved among evolutionarily distant organisms. In Drosophila melanogaster (the fly), ZnT9 (ZnT49B) knockdown results in acutely impaired movement and drastic mitochondrial deformation. Severe Drosophila ZnT9 (dZnT9) reduction and ZnT9-null mutant flies are pupal lethal. The phenotype of dZnT9 knockdown can be partially rescued by mouse ZnT9 expression or zinc chelator TPEN, indicating the defect of dZnT9 loss is indeed a result of zinc dyshomeostasis. Interestingly, in the mouse, germline loss of Znt9 produces even more extreme phenotypes: the mutant embryos exhibit midgestational lethality with severe development abnormalities. Targeted mutagenesis of Znt9 in the mouse brain leads to serious dwarfism and physical incapacitation, followed by death shortly. Strikingly, the GH/IGF-1 signals are almost non-existent in these tissue-specific knockout mice, consistent with the medical finding in some human patients with severe mitochondrial deficiecny. ZnT9 mutations cause mitochondrial zinc dyshomeostasis, and we demonstrate mechanistically that mitochondrial zinc elevation quickly and potently inhibits the activities of respiration complexes. These results reveal the critical role of ZnT9 and mitochondrial zinc homeostasis in mammalian development. Based on our functional analyses, we finally discussed the possible nature of the so far identified human SLC30A9 mutations.


Assuntos
Proteínas de Transporte de Cátions , Desenvolvimento Embrionário , Mitocôndrias , Zinco , Animais , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Transporte de Cátions/genética , Humanos , Zinco/metabolismo , Camundongos , Mitocôndrias/metabolismo , Desenvolvimento Embrionário/genética , Drosophila melanogaster/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/embriologia , Evolução Molecular , Camundongos Knockout , Sequência de Aminoácidos , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Fatores de Transcrição , Proteínas de Ciclo Celular
5.
J Biol Chem ; 299(7): 104923, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37321451

RESUMO

Mammalian brain tubulins undergo a reversible posttranslational modification-polyglutamylation-which attaches a secondary polyglutamate chain to the primary sequence of proteins. Loss of its erasers can disrupt polyglutamylation homeostasis and cause neurodegeneration. Tubulin tyrosine ligase like 4 (TTLL4) and TTLL7 were known to modify tubulins, both with preference for the ß-isoform, but differently contribute to neurodegeneration. However, differences in their biochemical properties and functions remain largely unknown. Here, using an antibody-based method, we characterized the properties of a purified recombinant TTLL4 and confirmed its sole role as an initiator, unlike TTLL7, which both initiates and elongates the side chains. Unexpectedly, TTLL4 produced stronger glutamylation immunosignals for α-isoform than ß-isoform in brain tubulins. Contrarily, the recombinant TTLL7 raised comparable glutamylation immunoreactivity for two isoforms. Given the site selectivity of the glutamylation antibody, we analyzed modification sites of two enzymes. Tandem mass spectrometry analysis revealed their incompatible site selectivity on synthetic peptides mimicking carboxyl termini of α1- and ß2-tubulins and a recombinant tubulin. Particularly, in the recombinant α1A-tubulin, a novel region was found glutamylated by TTLL4 and TTLL7, that again at distinct sites. These results pinpoint different site specificities between two enzymes. Moreover, TTLL7 exhibits less efficiency to elongate microtubules premodified by TTLL4, suggesting possible regulation of TTLL7 elongation activity by TTLL4-initiated sites. Finally, we showed that kinesin behaves differentially on microtubules modified by two enzymes. This study underpins the different reactivity, site selectivity, and function of TTLL4 and TTLL7 on brain tubulins and sheds light on their distinct role in vivo.


Assuntos
Microtúbulos , Peptídeo Sintases , Tubulina (Proteína) , Animais , Encéfalo/metabolismo , Microtúbulos/metabolismo , Ácido Poliglutâmico/química , Isoformas de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Tubulina (Proteína)/metabolismo , Peptídeo Sintases/metabolismo
6.
Plant Mol Biol ; 114(3): 64, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809410

RESUMO

Pollen tube growth is an essential step leading to reproductive success in flowering plants, in which vesicular trafficking plays a key role. Vesicular trafficking from endoplasmic reticulum to the Golgi apparatus is mediated by the coat protein complex II (COPII). A key component of COPII is small GTPase Sar1. Five Sar1 isoforms are encoded in the Arabidopsis genome and they show distinct while redundant roles in various cellular and developmental processes, especially in reproduction. Arabidopsis Sar1b is essential for sporophytic control of pollen development while Sar1b and Sar1c are critical for gametophytic control of pollen development. Because functional loss of Sar1b and Sar1c resulted in pollen abortion, whether they influence pollen tube growth was unclear. Here we demonstrate that Sar1b mediates pollen tube growth, in addition to its role in pollen development. Although functional loss of Sar1b does not affect pollen germination, it causes a significant reduction in male transmission and of pollen tube penetration of style. We further show that membrane dynamics at the apex of pollen tubes are compromised by Sar1b loss-of-function. Results presented provide further support of functional complexity of the Sar1 isoforms.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Tubo Polínico , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Tubo Polínico/crescimento & desenvolvimento , Tubo Polínico/metabolismo , Tubo Polínico/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Proteínas Monoméricas de Ligação ao GTP/genética , Regulação da Expressão Gênica de Plantas , Pólen/crescimento & desenvolvimento , Pólen/genética , Pólen/metabolismo , Plantas Geneticamente Modificadas , Germinação/genética
7.
Biochem Biophys Res Commun ; 716: 150002, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38697011

RESUMO

Type 2 diabetes mellitus (T2DM) significantly impairs the functionality and number of endothelial progenitor cells (EPCs) and resident endothelial cells, critical for vascular repair and regeneration, exacerbating the risk of vascular complications. GLP-1 receptor agonists, like dulaglutide, have emerged as promising therapeutic agents due to their multifaceted effects, including the enhancement of EPC activity and protection of endothelial cells. This study investigates dulaglutide's effects on peripheral blood levels of CD34+ and CD133+ cells in a mouse model of lower limb ischemia and its protective mechanisms against high-glucose-induced damage in endothelial cells. Results demonstrated that dulaglutide significantly improves blood flow, reduces tissue damage and inflammation in ischemic limbs, and enhances glycemic control. Furthermore, dulaglutide alleviated high-glucose-induced endothelial cell damage, evident from improved tube formation, reduced reactive oxygen species accumulation, and restored endothelial junction integrity. Mechanistically, dulaglutide mitigated mitochondrial fission in endothelial cells under high-glucose conditions, partly through maintaining SIRT1 expression, which is crucial for mitochondrial dynamics. This study reveals the potential of dulaglutide as a therapeutic option for vascular complications in T2DM patients, highlighting its role in improving endothelial function and mitochondrial integrity.


Assuntos
Diabetes Mellitus Experimental , Células Progenitoras Endoteliais , Peptídeos Semelhantes ao Glucagon , Glucose , Fragmentos Fc das Imunoglobulinas , Dinâmica Mitocondrial , Proteínas Recombinantes de Fusão , Sirtuína 1 , Animais , Camundongos , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Células Progenitoras Endoteliais/efeitos dos fármacos , Células Progenitoras Endoteliais/metabolismo , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Peptídeos Semelhantes ao Glucagon/farmacologia , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Glucose/metabolismo , Hipoglicemiantes/farmacologia , Fragmentos Fc das Imunoglobulinas/farmacologia , Isquemia/metabolismo , Isquemia/tratamento farmacológico , Isquemia/patologia , Camundongos Endogâmicos C57BL , Dinâmica Mitocondrial/efeitos dos fármacos , Proteínas Recombinantes de Fusão/farmacologia , Sirtuína 1/efeitos dos fármacos , Sirtuína 1/metabolismo
8.
Plant Physiol ; 193(1): 140-155, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-36974907

RESUMO

Pollen germination is a process of polarity establishment, through which a single and unique growth axis is established. Although most of the intracellular activities associated with pollen germination are controlled by RHO OF PLANTs (ROPs) and increased ROP activation accompanies pollen germination, a critical role of ROPs in this process has not yet been demonstrated. Here, by genomic editing of all 4 Arabidopsis (Arabidopsis thaliana) ROPs that are preferentially expressed in pollen, we showed that ROPs are essential for polarity establishment during pollen germination. We further identified and characterized 2 ROP effectors in pollen germination (REGs) through genome-wide interactor screening, boundary of ROP domain (BDR) members BDR8 and BDR9, whose functional loss also resulted in no pollen germination. BDR8 and BDR9 were distributed in the cytosol and the vegetative nucleus of mature pollen grains but redistributed to the plasma membrane (PM) of the germination site and to the apical PM of growing pollen tubes. We demonstrated that the PM redistribution of BDR8 and BDR9 during pollen germination relies on ROPs but not vice versa. Furthermore, enhanced expression of BDR8 partially restored germination of rop1 pollen but had no effects on that of the quadruple rop pollen, supporting their genetic epistasis. Results presented here demonstrate an ROP signaling route essential for pollen germination, which supports evolutionarily conserved roles of Rho GTPases in polarity establishment.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Tubo Polínico , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Germinação , Tubo Polínico/crescimento & desenvolvimento , Proteínas de Arabidopsis/metabolismo , Infertilidade das Plantas , Epistasia Genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Pólen/citologia , Pólen/metabolismo
9.
J Exp Bot ; 75(11): 3300-3321, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38447063

RESUMO

In a gene chip analysis, rice (Oryza sativa) OsSMP2 gene expression was induced under various abiotic stresses, prompting an investigation into its role in drought resistance and abscisic acid signaling. Subsequent experiments, including qRT-PCR and ß-glucuronidase activity detection, affirmed the OsSMP2 gene's predominant induction by drought stress. Subcellular localization experiments indicated the OsSMP2 protein primarily localizes to the cell membrane system. Overexpressing OsSMP2 increased sensitivity to exogenous abscisic acid, reducing drought resistance and leading to reactive oxygen species accumulation under drought stress. Conversely, in simulated drought experiments, OsSMP2-silenced transgenic plants showed significantly longer roots compared with the wild-type Nipponbare. These results suggest that OsSMP2 overexpression negatively affects rice drought resistance, offering valuable insights into molecular mechanisms, and highlight OsSMP2 as a potential target for enhancing crop resilience to drought stress.


Assuntos
Ácido Abscísico , Secas , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Estresse Fisiológico , Oryza/genética , Oryza/fisiologia , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Ácido Abscísico/metabolismo , Plantas Geneticamente Modificadas , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética
10.
Glob Chang Biol ; 30(1): e17109, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273550

RESUMO

Agricultural soils play a dual role in regulating the Earth's climate by releasing or sequestering carbon dioxide (CO2 ) in soil organic carbon (SOC) and emitting non-CO2 greenhouse gases (GHGs) such as nitrous oxide (N2 O) and methane (CH4 ). To understand how agricultural soils can play a role in climate solutions requires a comprehensive assessment of net soil GHG balance (i.e., sum of SOC-sequestered CO2 and non-CO2 GHG emissions) and the underlying controls. Herein, we used a model-data integration approach to understand and quantify how natural and anthropogenic factors have affected the magnitude and spatiotemporal variations of the net soil GHG balance in U.S. croplands during 1960-2018. Specifically, we used the dynamic land ecosystem model for regional simulations and used field observations of SOC sequestration rates and N2 O and CH4 emissions to calibrate, validate, and corroborate model simulations. Results show that U.S. agricultural soils sequestered 13.2 ± 1.16 $$ 13.2\pm 1.16 $$ Tg CO2 -C year-1 in SOC (at a depth of 3.5 m) during 1960-2018 and emitted 0.39 ± 0.02 $$ 0.39\pm 0.02 $$ Tg N2 O-N year-1 and 0.21 ± 0.01 $$ 0.21\pm 0.01 $$ Tg CH4 -C year-1 , respectively. Based on the GWP100 metric (global warming potential on a 100-year time horizon), the estimated national net GHG emission rate from agricultural soils was 122.3 ± 11.46 $$ 122.3\pm 11.46 $$ Tg CO2 -eq year-1 , with the largest contribution from N2 O emissions. The sequestered SOC offset ~28% of the climate-warming effects resulting from non-CO2 GHG emissions, and this offsetting effect increased over time. Increased nitrogen fertilizer use was the dominant factor contributing to the increase in net GHG emissions during 1960-2018, explaining ~47% of total changes. In contrast, reduced cropland area, the adoption of agricultural conservation practices (e.g., reduced tillage), and rising atmospheric CO2 levels attenuated net GHG emissions from U.S. croplands. Improving management practices to mitigate N2 O emissions represents the biggest opportunity for achieving net-zero emissions in U.S. croplands. Our study highlights the importance of concurrently quantifying SOC-sequestered CO2 and non-CO2 GHG emissions for developing effective agricultural climate change mitigation measures.


Assuntos
Gases de Efeito Estufa , Solo , Dióxido de Carbono/análise , Ecossistema , Carbono , Agricultura , Óxido Nitroso/análise , Metano/análise , Produtos Agrícolas , Efeito Estufa
11.
BMC Cancer ; 24(1): 172, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310286

RESUMO

BACKGROUND: Epithelioid sarcoma is a rare soft tissue sarcoma characterized by SMARCB1/INI1 deficiency. Much attention has been paid to the selective EZH2 inhibitor tazemetostat, where other systemic treatments are generally ignored. To explore alternative treatment options, we studied the effects of irinotecan-based chemotherapy in a series of epithelioid sarcoma patients. METHODS: We retrospectively reviewed data from patients with metastatic or unresectable epithelioid sarcoma at the Peking University People's Hospital treated with irinotecan (50 mg/m2/d d1-5 Q3W) in combination with Anlotinib (12 mg Qd, 2 weeks on and 1 week off) from July 2015 to November 2021. RESULTS: A total of 54 courses were administered. With a median follow up of 21.2 months (95% CI, 12.2, 68.1), the 5-year overall survival rate was 83.3%. Five of eight (62.5%) patients presented with unresectable localized lesions, including local tumor thrombosis and lymphatic metastasis. The other patients had unresectable pulmonary metastases. Six of eight (75%) patients had progressed following two lines of systemic therapy. The objective response rate reached 37.5% (three of eight patients) while stabilized disease was observed in 62.5% (five of eight) of patients. No patient had progressed at initial evaluation. At the last follow up, two patients were still using the combination and three patients had ceased the therapy due to toxicities such as diarrhea, nausea, and emesis. One patient changed to tazemetostat for maintenance and one patient stopped treatment due to coronavirus disease 2019 (COVID-19). Another patient stopped therapy as residual lesions had been radiated. CONCLUSIONS: The combination of irinotecan and Anlotinib as a salvage regimen may be considered another effective treatment option for refractory epithelioid sarcoma. TRIAL REGISTRATION: This study was approved in the Medical Ethics Committee of Peking University People's Hospital on October 28, 2022 (No.: 2022PHD015-002). The study was registered in Clinicaltrials.gov with identifier no. NCT05656222.


Assuntos
Benzamidas , Compostos de Bifenilo , Indóis , Morfolinas , Piridonas , Quinolinas , Sarcoma , Humanos , Irinotecano/uso terapêutico , Vincristina/uso terapêutico , Estudos Retrospectivos , Sarcoma/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
12.
Chemphyschem ; 25(16): e202400413, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-38747673

RESUMO

In order to explore the unique physiological roles of gas signaling molecules and gasotransmitters in vivo, chemists have engineered a variety of gas-responsive polymers that can monitor their changes in cellular milieu, and gas-releasing polymers that can orchestrate the release of gases. These have advanced their potential applications in the field of bio-imaging, nanodelivery, and theranostics. Since these polymers are of different chain structures and properties, the morphology of their assemblies will manifest distinct transitions after responding to gas or releasing gas. In this review, we summarize the fundamental design rationale of gas-responsive and gas-releasing polymers in structure and their controlled transition in self-assembled morphology and function, as well as present some perspectives in this prosperous field. Emerging challenges faced for the future research are also discussed.


Assuntos
Gases , Polímeros , Polímeros/química , Gases/química , Humanos
13.
Pharmacol Res ; 206: 107266, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38878918

RESUMO

Cerebral ischemia-reperfusion injury (I/RI) is one of the principal pathogenic factors in the poor prognosis of ischemic stroke, for which current therapeutic options to enhance neurological recovery are notably insufficient. Dental pulp stem cell-derived extracellular vesicles (DPSC-EVs) have promising prospects in stroke treatment and the specific underlying mechanisms have yet to be fully elucidated. The present study observed that DPSC-EVs ameliorated the degree of cerebral edema and infarct volume by reducing the apoptosis of neurons. Furthermore, the miRNA sequencing and functional enrichment analysis identified that miR-877-3p as a key component in DPSC-EVs, contributing to neuroprotection and anti-apoptotic effects. Following target prediction and dual-luciferase assay indicated that miR-877-3p interacted with Bcl-2-associated transcription factor (Bclaf1) to play a function. The miR-877-3p inhibitor or Bclaf1 overexpression reversed the neuroprotective effects of DPSC-EVs. The findings reveal a novel therapeutic pathway where miR-877-3p, transferred via DPSC-EVs, confers neuroprotection against cerebral I/RI, highlighting its potential in promoting neuronal survival and recovery post-ischemia.


Assuntos
Apoptose , Polpa Dentária , Vesículas Extracelulares , MicroRNAs , Neurônios , Recuperação de Função Fisiológica , Traumatismo por Reperfusão , Transdução de Sinais , Células-Tronco , MicroRNAs/genética , MicroRNAs/metabolismo , Animais , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/transplante , Polpa Dentária/citologia , Polpa Dentária/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/terapia , Neurônios/metabolismo , Neurônios/patologia , Masculino , Células-Tronco/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Ratos Sprague-Dawley , Isquemia Encefálica/metabolismo , Isquemia Encefálica/genética , Camundongos Endogâmicos C57BL , Ratos , Células Cultivadas
14.
J Org Chem ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39180143

RESUMO

Total syntheses of the title prenylated indole alkaloids together with seven others are reported. Biogenetic considerations have been employed in devising the reaction sequences leading to these targets with, in the opening stages, electrochemically-derived indole-3-carboxaldehyde 15 being subject to an aldol-type condensation reaction involving diketopiperazine derivative 19. This led, after prototopic shifts, intramolecular Diels-Alder cycloaddition and hydrolysis/deprotection steps, to the racemic forms of the bicyclo[2.2.2]diazaoctane-containing natural product stephacidin A (2) and its C6 epimer 3. Epoxidation of the last compound afforded, following rearrangement of the primary oxidation products, a mixture of (±)-taichunamide A [(±)-4] and (±)-versicolamide B [(±)-7]. Related protocols allowed for the conversion of (±)-stephacidin A [(±)-2] into (±)-notoamide B [(±)-5]. Analogous aldol condensation, nucleophilic reduction, and epoxidation steps led to the formation of (-)-notoamide E and its conversion into notoamide C as well as the indole fragmentation product amoenamide E. A late-stage chlorination reaction applied to (±)-stephacidin A provided access to the spirocyclic oxindole (±)-notoamide N [(±)-6].

15.
J Org Chem ; 89(6): 3931-3940, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38450634

RESUMO

The electrochemical oxidative radical-radical cross-coupling of sulfonyl hydrazides with diselenides for the synthesis of selenosulfonates was successfully accomplished. The method is applicable to a wide range of aromatic/aliphatic sulfonyl hydrazides and diselenides, providing products in good to excellent yields. Notably, this protocol stands out for its green and sustainable nature, as it does not rely on transition metals and oxidizing agents, and the starting materials are cost-effective and readily available.

16.
J Surg Oncol ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39082465

RESUMO

Malignant peritoneal mesothelioma (MPM) is a rare and invasive tumor, and some patients will develop paraneoplastic syndrome (PS) during the course of the disease. This review summarizes PS associated with MPM, focusing on the clinical characteristics and treatment progress in hematological, endocrine, rheumatic, neurological, urinary, and other systems to decrease missed diagnosis and misdiagnosis, help early diagnosis and prompt treatment, and provide guidance for the clinical decision-making of this kind of patients.

17.
J Surg Oncol ; 2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-39183488

RESUMO

BACKGROUND: To explore the most effective adjuvant chemotherapy regimen for malignant peritoneal mesothelioma (MPM) through patient derived tumor-like cell clusters (PTC) drug sensitivity test. METHODS: PTC were cultured in vitro with intraoperative specimens, and drug sensitivity test was performed to calculate the most effective chemotherapy regimen for MPM. The patients were divided into conventional and individualized chemotherapy group according to whether they received PTC drug testing. Univariate and multivariate analyses were conducted to identify independent prognostic factors. RESULTS: Among 186 MPM patients included, 63 underwent PTC culture and drug sensitivity test. The results showed that the most effective chemotherapy regimen was oxaliplatin + gemcitabine. After propensity score matching, a total of 64 patients were enrolled in the following study, including 32 patients receiving individualized chemotherapy guided by PTC drug results as group 1 and 32 patients receiving conventional chemotherapy as group 2. Survival analysis showed that the median OS of group 1 was not reached, significantly longer than that of group 2 (23.5 months) (p < 0.05). CONCLUSIONS: Compared with conventional chemotherapy, individualized chemotherapy guided by PTC drug sensitivity tests can prolong patient survival, and oxaliplatin + gemcitabine + apatinib could be the optimal adjuvant treatment regimen for MPM.

18.
Int J Legal Med ; 138(1): 197-206, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37804331

RESUMO

Given that combination with multiple biomarkers may well raise the predictive value of wound age, it appears critically essential to identify new features under the limited cost. For this purpose, the present study explored whether the gene expression ratios provide unique time information as an additional indicator for wound age estimation not requiring the detection of new biomarkers and allowing full use of the available data. The expression levels of four wound-healing genes (Arid5a, Ier3, Stom, and Lcp1) were detected by real-time polymerase chain reaction, and a total of six expression ratios were calculated among these four genes. The results showed that the expression levels of four genes and six ratios of expression changed time-dependent during wound repair. The six expression ratios provided additional temporal information, distinct from the four genes analyzed separately by principal component analysis. The overall performance metrics for cross-validation and external validation of four typical prediction models were improved when six ratios of expression were added as additional input variables. Overall, expression ratios among genes provide temporal information and have excellent potential as predictive markers for wound age estimation. Combining the expression levels of genes with ratio-expression of genes may allow for more accurate estimates of the time of injury.


Assuntos
Contusões , Ratos , Animais , Humanos , Ratos Sprague-Dawley , Contusões/genética , Contusões/metabolismo , Músculo Esquelético/metabolismo , Cicatrização/genética , Biomarcadores/metabolismo
19.
Paediatr Perinat Epidemiol ; 38(4): 345-356, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38146616

RESUMO

BACKGROUND: Accumulating studies indicate that maternal obesity is associated with the risk of cerebral palsy (CP); however, their conclusions have been inconsistent. OBJECTIVES: To quantitatively estimate the association between maternal body mass index (BMI) and CP in offspring. DATA SOURCES: PubMed, Embase and Web of Science. STUDY SELECTION AND DATA EXTRACTION: Articles published up to 18 September 2022 were searched that reported the correlation between maternal BMI and CP in children. Two reviewers independently extracted data and critically assessed articles. SYNTHESIS: Pooled relative risks (RR) and 95% confidence intervals (CI) were estimated by the random-effects model. Subgroup analysis and meta-regression were performed to explore sources of heterogeneity. RESULTS: In total, 11 articles (8,407,668 participants) were identified for inclusion in our meta-analysis. For maternal underweight, no significant association was found with CP risk (RR 1.11, 95% CI 0.90, 1.38). The risk of CP was increased by 25% (RR 1.25, 95% CI 1.06, 1.47), 38% (RR 1.38, 95% CI 1.18, 1.61) and 127% (RR 2.27, 95% CI 1.82, 2.83) for maternal overweight, obesity and obesity grade 3, respectively. In addition, we observed a positive linear dose-response relationship, with the pooled risk of cerebral palsy in offspring increasing by 3% with each unit increase in maternal BMI. CONCLUSION: This meta-analysis indicates that the risk of CP in offspring grew with maternal overweight or obesity grades increasing, and was positively correlated with maternal BMI.


Assuntos
Índice de Massa Corporal , Paralisia Cerebral , Humanos , Paralisia Cerebral/epidemiologia , Paralisia Cerebral/etiologia , Feminino , Gravidez , Criança , Fatores de Risco , Obesidade Materna/epidemiologia , Obesidade Materna/complicações
20.
Int J Geriatr Psychiatry ; 39(5): e6093, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38752607

RESUMO

BACKGROUND: Dementia is a significant cause of death in the older population and is becoming an important public health issue as the population ages and the prevalence of dementia increases. The Braden score is one of the most commonly used clinical tools to assess the risk of skin pressure injury in patients, and some studies have reported that it may reflect the state of frailty of patients. The present study attempted to explore the association between Braden score and 90-day mortality, pressure injury, and aspiration pneumonia in older patients with dementia in the intensive care unit (ICU). METHODS: The study involved extracting crucial data from the Medical Information Market for Intensive Care IV (MIMIC-IV) database using Structured Query Language, with a license certificate obtained after completing the necessary training and examination available on the MIMIC-IV website. A retrospective analysis was performed on older patients with dementia, aged 65 or older, who were first admitted to the ICU. Ninth and tenth revision International Classification of Diseases codes were used to identify patients with dementia. The primary outcome was 90-day mortality. Cox proportional hazards models were used to determine the association between Braden score and death, and hazard ratios (HR) and 95% confidence intervals (CI) were calculated. Propensity score matching and E-value assessments were employed for sensitivity analysis. RESULTS: A total of 2892 patients with a median age of approximately 85 years (interquartile range 78.74-89.59) were included, of whom 1625 were female (56.2%). Patients had a median Braden score of 14 (interquartile range 12-15) at ICU admission. Braden score at ICU admission was inversely associated with 90-day mortality risk after adjustment for demographics, severity of illness, treatment and medications, delirium, and sepsis (adjusted HR: 0.92, 95% CI: 0.87-0.98, p = 0.006). Patients were divided into two groups with a cut-off value of 15: high-risk group and low-risk group. Compared to the low-risk group (Braden score >15), the risk of 90-day mortality was significantly increased in the high-risk group (Braden score ≤15) (adjusted HR: 1.52, 95% CI: 1.10-2.09, p = 0.011, E-value: 2.01), the risk of pressure injury (adjusted OR: 2.62, 95% CI: 2.02-3.43, E-value: 2.62) and aspiration pneumonia (adjusted OR: 2.55, 95% CI: 1.84-3.61, E-value: 2.57) was also significantly higher. CONCLUSIONS: The Braden score may be a quick and simple screening tool to identify the risk of adverse outcomes in critically ill older adults with dementia.


Assuntos
Estado Terminal , Demência , Unidades de Terapia Intensiva , Humanos , Feminino , Masculino , Idoso , Idoso de 80 Anos ou mais , Demência/mortalidade , Estado Terminal/mortalidade , Unidades de Terapia Intensiva/estatística & dados numéricos , Estudos Retrospectivos , Úlcera por Pressão/mortalidade , Modelos de Riscos Proporcionais , Pneumonia Aspirativa/mortalidade , Pontuação de Propensão , Mortalidade Hospitalar
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