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1.
Mol Cell ; 84(4): 744-759.e6, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38266638

RESUMEN

Serine metabolism is involved in the fate decisions of immune cells; however, whether and how de novo serine synthesis shapes innate immune cell function remain unknown. Here, we first demonstrated that inflammatory macrophages have high expression of phosphoglycerate dehydrogenase (PHGDH, the rate-limiting enzyme of de novo serine synthesis) via nuclear factor κB signaling. Notably, the pharmacological inhibition or genetic modulation of PHGDH limits macrophage interleukin (IL)-1ß production through NAD+ accumulation and subsequent NAD+-dependent SIRT1 and SIRT3 expression and activity. Mechanistically, PHGDH not only sustains IL-1ß expression through H3K9/27 acetylation-mediated transcriptional activation of Toll-like receptor 4 but also supports IL-1ß maturation via NLRP3-K21/22/24/ASC-K21/22/24 acetylation-mediated activation of the NLRP3 inflammasome. Moreover, mice with myeloid-specific depletion of Phgdh show alleviated inflammatory responses in lipopolysaccharide-induced systemic inflammation. This study reveals a network by which a metabolic enzyme, involved in de novo serine synthesis, mediates post-translational modifications and epigenetic regulation to orchestrate IL-1ß production, providing a potential inflammatory disease target.


Asunto(s)
NAD , Proteína con Dominio Pirina 3 de la Familia NLR , Animales , Ratones , Acetilación , Epigénesis Genética , Inflamasomas/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , NAD/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Procesamiento Proteico-Postraduccional , Serina/metabolismo
2.
Nat Immunol ; 20(4): 433-446, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30804553

RESUMEN

Cells use mitophagy to remove damaged or unwanted mitochondria to maintain homeostasis. Here we report that the intracellular bacterial pathogen Listeria monocytogenes exploits host mitophagy to evade killing. We found that L. monocytogenes induced mitophagy in macrophages through the virulence factor listeriolysin O (LLO). We discovered that NLRX1, the only Nod-like receptor (NLR) family member with a mitochondrial targeting sequence, contains an LC3-interacting region (LIR) and directly associated with LC3 through the LIR. NLRX1 and its LIR motif were essential for L. monocytogenes-induced mitophagy. NLRX1 deficiency and use of a mitophagy inhibitor both increased mitochondrial production of reactive oxygen species and thereby suppressed the survival of L. monocytogenes. Mechanistically, L. monocytogenes and LLO induced oligomerization of NLRX1 to promote binding of its LIR motif to LC3 for induction of mitophagy. Our study identifies NLRX1 as a novel mitophagy receptor and discovers a previously unappreciated strategy used by pathogens to hijack a host cell homeostasis system for their survival.


Asunto(s)
Listeria monocytogenes/fisiología , Proteínas Mitocondriales/fisiología , Mitofagia , Animales , Autofagia , Toxinas Bacterianas/metabolismo , Línea Celular , Femenino , Proteínas de Choque Térmico/metabolismo , Proteínas Hemolisinas/metabolismo , Humanos , Listeria monocytogenes/patogenicidad , Listeriosis/metabolismo , Listeriosis/microbiología , Macrófagos/microbiología , Macrófagos/ultraestructura , Masculino , Ratones , Ratones Noqueados , Viabilidad Microbiana , Mitocondrias/metabolismo , Mitocondrias/ultraestructura , Proteínas Mitocondriales/química , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Dominios Proteicos , Especies Reactivas de Oxígeno/metabolismo , Factores de Virulencia/metabolismo
3.
Nature ; 632(8024): 267-272, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38987606

RESUMEN

The fermionic Hubbard model (FHM)1 describes a wide range of physical phenomena resulting from strong electron-electron correlations, including conjectured mechanisms for unconventional superconductivity. Resolving its low-temperature physics is, however, challenging theoretically or numerically. Ultracold fermions in optical lattices2,3 provide a clean and well-controlled platform offering a path to simulate the FHM. Doping the antiferromagnetic ground state of a FHM simulator at half-filling is expected to yield various exotic phases, including stripe order4, pseudogap5, and d-wave superfluid6, offering valuable insights into high-temperature superconductivity7-9. Although the observation of antiferromagnetic correlations over short10 and extended distances11 has been obtained, the antiferromagnetic phase has yet to be realized as it requires sufficiently low temperatures in a large and uniform quantum simulator. Here we report the observation of the antiferromagnetic phase transition in a three-dimensional fermionic Hubbard system comprising lithium-6 atoms in a uniform optical lattice with approximately 800,000 sites. When the interaction strength, temperature and doping concentration are finely tuned to approach their respective critical values, a sharp increase in the spin structure factor is observed. These observations can be well described by a power-law divergence, with a critical exponent of 1.396 from the Heisenberg universality class12. At half-filling and with optimal interaction strength, the measured spin structure factor reaches 123(8), signifying the establishment of an antiferromagnetic phase. Our results provide opportunities for exploring the low-temperature phase diagram of the FHM.

4.
EMBO J ; 43(7): 1301-1324, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38467834

RESUMEN

Upon replication fork stalling, the RPA-coated single-stranded DNA (ssDNA) formed behind the fork activates the ataxia telangiectasia-mutated and Rad3-related (ATR) kinase, concomitantly initiating Rad18-dependent monoubiquitination of PCNA. However, whether crosstalk exists between these two events and the underlying physiological implications of this interplay remain elusive. In this study, we demonstrate that during replication stress, ATR phosphorylates human Rad18 at Ser403, an adjacent residue to a previously unidentified PIP motif (PCNA-interacting peptide) within Rad18. This phosphorylation event disrupts the interaction between Rad18 and PCNA, thereby restricting the extent of Rad18-mediated PCNA monoubiquitination. Consequently, excessive accumulation of the tumor suppressor protein SLX4, now characterized as a novel reader of ubiquitinated PCNA, at stalled forks is prevented, contributing to the prevention of stalled fork collapse. We further establish that ATR preserves telomere stability in alternative lengthening of telomere (ALT) cells by restricting Rad18-mediated PCNA monoubiquitination and excessive SLX4 accumulation at telomeres. These findings shed light on the complex interplay between ATR activation, Rad18-dependent PCNA monoubiquitination, and SLX4-associated stalled fork processing, emphasizing the critical role of ATR in preserving replication fork stability and facilitating telomerase-independent telomere maintenance.


Asunto(s)
Telomerasa , Humanos , Antígeno Nuclear de Célula en Proliferación/genética , Antígeno Nuclear de Célula en Proliferación/metabolismo , Telomerasa/genética , Ubiquitinación , Replicación del ADN , Telómero/genética , Telómero/metabolismo , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Daño del ADN
5.
Cell ; 152(4): 909-22, 2013 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-23394947

RESUMEN

Genetic interaction (GI) maps, comprising pairwise measures of how strongly the function of one gene depends on the presence of a second, have enabled the systematic exploration of gene function in microorganisms. Here, we present a two-stage strategy to construct high-density GI maps in mammalian cells. First, we use ultracomplex pooled shRNA libraries (25 shRNAs/gene) to identify high-confidence hit genes for a given phenotype and effective shRNAs. We then construct double-shRNA libraries from these to systematically measure GIs between hits. A GI map focused on ricin susceptibility broadly recapitulates known pathways and provides many unexpected insights. These include a noncanonical role for COPI, a previously uncharacterized protein complex affecting toxin clearance, a specialized role for the ribosomal protein RPS25, and functionally distinct mammalian TRAPP complexes. The ability to rapidly generate mammalian GI maps provides a potentially transformative tool for defining gene function and designing combination therapies based on synergistic pairs.


Asunto(s)
Transporte Biológico , Epistasis Genética , Ricina/toxicidad , Atorvastatina , Proteínas Portadoras/metabolismo , Línea Celular Tumoral , Proteína Coat de Complejo I/metabolismo , Retículo Endoplásmico/metabolismo , Ácidos Heptanoicos/farmacología , Humanos , Proteínas de la Membrana/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Pirroles/farmacología , ARN Interferente Pequeño , Proteínas Ribosómicas/metabolismo , Proteínas de Transporte Vesicular/metabolismo
6.
Genome Res ; 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39137961

RESUMEN

Chromatin loop identification plays an important role in molecular biology and 3D genomics research, as it constitutes a fundamental process in transcription and gene regulation. Such precise chromatin structures can be identified across genome-wide interaction matrices via Hi-C data analysis, which is essential for unraveling the intricacies of transcriptional regulation. Given the increasing number of genome-wide contact maps, derived from both in situ Hi-C and single-cell Hi-C experiments, there is a pressing need for efficient and resilient algorithms capable of processing data from diverse experiments rapidly and adaptively. Here, we propose YOLOOP, a novel detection-based framework that is different from the conventional paradigm. YOLOOP stands out for its speed, surpassing the performance of previous state-of-the-art (SOTA) chromatin loop detection methods. It achieves a 30-fold acceleration compared with classification-based methods, up to 20-fold acceleration compared with the SOTA kernel-based framework, and a fivefold acceleration compared with statistical algorithms. Furthermore, the proposed framework is capable of generalizing across various cell types, multiresolution Hi-C maps, and diverse experimental protocols. Compared with the existing paradigms, YOLOOP shows up to a 10% increase in recall and a 15% increase in F1-score, particularly noteworthy in the GM12878 cell line. YOLOOP also offers fast adaptability with straightforward fine-tuning, making it readily applicable to extremely sparse single-cell Hi-C contact maps. It maintains its exceptional speed, completing genome-wide detection at a 10 kb resolution for a single-cell contact map within 1 min and for a 900-cell-superimposed contact map within 3 min, enabling fast analysis of large-scale single-cell data.

7.
Proc Natl Acad Sci U S A ; 121(25): e2316551121, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38865260

RESUMEN

The NLRP3 inflammasome, a pivotal component of innate immunity, has been implicated in various inflammatory disorders. The ubiquitin-editing enzyme A20 is well known to regulate inflammation and maintain homeostasis. However, the precise molecular mechanisms by which A20 modulates the NLRP3 inflammasome remain poorly understood. Here, our study revealed that macrophages deficient in A20 exhibit increased protein abundance and elevated mRNA level of NIMA-related kinase 7 (NEK7). Importantly, A20 directly binds with NEK7, mediating its K48-linked ubiquitination, thereby targeting NEK7 for proteasomal degradation. Our results demonstrate that A20 enhances the ubiquitination of NEK7 at K189 and K293 ubiquitinated sites, with K189 playing a crucial role in the binding of NEK7 to A20, albeit not significantly influencing the interaction between NEK7 and NLRP3. Furthermore, A20 disrupts the association of NEK7 with the NLRP3 complex, potentially through the OTU domain and/or synergistic effect of ZnF4 and ZnF7 motifs. Significantly, NEK7 deletion markedly attenuates the activation of the NLRP3 inflammasome in A20-deficient conditions, both in vitro and in vivo. This study uncovers a mechanism by which A20 inhibits the NLRP3 inflammasome.


Asunto(s)
Inflamasomas , Quinasas Relacionadas con NIMA , Proteína con Dominio Pirina 3 de la Familia NLR , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa , Ubiquitinación , Quinasas Relacionadas con NIMA/metabolismo , Quinasas Relacionadas con NIMA/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Inflamasomas/metabolismo , Animales , Ratones , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa/metabolismo , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa/genética , Humanos , Macrófagos/metabolismo , Macrófagos/inmunología , Células HEK293 , Ratones Noqueados , Unión Proteica
8.
Proc Natl Acad Sci U S A ; 121(15): e2309087121, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38557184

RESUMEN

Africa carries a disproportionately high share of the global malaria burden, accounting for 94% of malaria cases and deaths worldwide in 2019. It is also a politically unstable region and the most vulnerable continent to climate change in recent decades. Knowledge about the modifying impacts of violent conflict on climate-malaria relationships remains limited. Here, we quantify the associations between violent conflict, climate variability, and malaria risk in sub-Saharan Africa using health surveys from 128,326 individuals, historical climate data, and 17,429 recorded violent conflicts from 2006 to 2017. We observe that spatial spillovers of violent conflict (SSVCs) have spatially distant effects on malaria risk. Malaria risk induced by SSVCs within 50 to 100 km from the households gradually increases from 0.1% (not significant, P>0.05) to 6.5% (95% CI: 0 to 13.0%). SSVCs significantly promote malaria risk within the average 20.1 to 26.9 °C range. At the 12-mo mean temperature of 22.5 °C, conflict deaths have the largest impact on malaria risk, with an approximately 5.8% increase (95% CI: 1.0 to 11.0%). Additionally, a pronounced association between SSVCs and malaria risk exists in the regions with 9.2 wet days per month. The results reveal that SSVCs increase population exposure to harsh environments, amplifying the effect of warm temperature and persistent precipitation on malaria transmission. Violent conflict therefore poses a substantial barrier to mosquito control and malaria elimination efforts in sub-Saharan Africa. Our findings support effective targeting of treatment programs and vector control activities in conflict-affected regions with a high malaria risk.


Asunto(s)
Exposición a la Violencia , Malaria , Humanos , Malaria/epidemiología , África del Sur del Sahara/epidemiología , Temperatura
9.
Plant J ; 118(6): 2003-2019, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38536089

RESUMEN

Plant height (PH) is an important factor affecting bast fiber yield in jute. Here, we report the mechanism of dwarfism in the 'Guangbaai' (gba) of jute. The mutant gba had shorter internode length and cell length compared to the standard cultivar 'TaiZi 4' (TZ4). Exogenous GA3 treatment indicated that gba is a GA-insensitive dwarf mutant. Quantitative trait locus (QTL) analysis of three PH-related traits via a high-density genetic linkage map according to re-seq showed that a total of 25 QTLs were identified, including 13 QTLs for PH, with phenotypic variation explained ranging from 2.42 to 74.16%. Notably, the functional mechanism of the candidate gene CoGID1a, the gibberellic acid receptor, of the major locus qPHIL5 was evaluated by transgenic analysis and virus-induced gene silencing. A dwarf phenotype-related single nucleotide mutation in CoGID1a was identified in gba, which was also unique to the dwarf phenotype of gba among 57 cultivars. Cogid1a was unable to interact with the growth-repressor DELLA even in the presence of highly accumulated gibberellins in gba. Differentially expressed genes between transcriptomes of gba and TZ4 after GA3 treatment indicated up-regulation of genes involved in gibberellin and cellulose synthesis in gba. Interestingly, it was found that up-regulation of CoMYB46, a key transcription factor in the secondary cell wall, by the highly accumulated gibberellins in gba promoted the expression of cellulose synthase genes CoCesA4 and CoCesA7. These findings provide valuable insights into fiber development affected by endogenous gibberellin accumulation in plants.


Asunto(s)
Celulosa , Corchorus , Proteínas de Plantas , Tallos de la Planta , Celulosa/metabolismo , Clonación Molecular , Corchorus/genética , Corchorus/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Giberelinas/metabolismo , Fenotipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tallos de la Planta/genética , Tallos de la Planta/crecimiento & desarrollo , Tallos de la Planta/metabolismo , Plantas Modificadas Genéticamente , Sitios de Carácter Cuantitativo/genética
10.
J Immunol ; 210(2): 180-190, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36458991

RESUMEN

Acute pancreatitis (AP) can be complicated by inflammatory disorders of remote organs, such as lung injury, in which Jumonji domain-containing protein 3 (JMJD3) plays a vital role in proinflammatory responses. Currently, we found that JMJD3 expression was upregulated in the pancreas and lung in an AP male mouse model, which was also confirmed in AP patients. Further experiments revealed that the upregulation of JMJD3 and proinflammatory effects were possibly exerted by mitochondrial DNA (mtDNA) or oxidized-mtDNA from tissue injury caused by AP. The release of mtDNA and oxidized-mtDNA contributed to the infiltration of inflammatory monocytes in lung injury through the stimulator of IFN genes (STING)/TLR9-NF-κB-JMJD3-TNF-α pathway. The inhibition of JMJD3 or utilization of Jmjd3-cKO mice significantly alleviated pulmonary inflammation induced by AP. Blocking mtDNA oxidation or knocking down the TLR9/STING pathway effectively alleviated inflammation. Therefore, inhibition of JMJD3 or STING/TLR9 pathway blockage might be a potential therapeutic strategy to treat AP and the associated lung injury.


Asunto(s)
Lesión Pulmonar , Pancreatitis , Masculino , Ratones , Animales , Receptor Toll-Like 9/metabolismo , Enfermedad Aguda , FN-kappa B/metabolismo , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo
11.
Neurobiol Dis ; 190: 106379, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38104911

RESUMEN

BACKGROUND: Cognitive impairment is a serious nonmotor symptom in patients with Parkinson's disease (PD). Currently, there are few studies investigating the relationship of serum markers and retinal structural changes with cognitive function in PD. OBJECTIVE: To investigate the relationship between retinal structural changes, serum high mobility group box-1 (HMGB1) levels and cognitive function and motor symptoms in PD patients. METHODS: Eighty-nine participants, including 47 PD patients and 42 healthy subjects, were enrolled. PD patients were divided into Parkinson's disease with normal cognitive (PD-NC), Parkinson's disease with mild cognitive impairment (PD-MCI), and Parkinson's disease with dementia (PDD) groups. The motor and nonmotor symptoms of PD patients were evaluated with clinical scale. Serum HMGB1 levels were detected by enzyme-linked immunosorbent assay (ELISA), and ganglion cell-inner plexiform layer complex (GCIPL) thickness changes in the macula were quantitatively analyzed by swept source optical coherence tomography (SS-OCT) in all patients. RESULTS: Compared with the control group, the macular GCIPL (t = -2.308, P = 0.023) was thinner and serum HMGB1 (z = -2.285, P = 0.022) was increased in PD patients. Macular GCIPL thickness in patients with PD-MCI and PDD were significantly lower than that in PD-NC patients, but there were no significant difference between the PD-MCI and PDD groups. Serum HMGB1 levels in patients with PD-MCI and PDD were significantly higher than those in PD-NC patients, and serum HMGB1 levels in PDD patients were higher than those in PD-MCI patients. Correlation analysis showed that serum HMGB1 levels in PD patients were positively correlated with disease duration, HY stage, UPDRS-I score, UPDRS-III score, and UPDRS total score and negatively correlated with MOCA score. Macular GCIPL thickness was negatively correlated with HY stage and positively correlated with MOCA score, and macular GCIPL thickness was negatively correlated with serum HMGB1 level. Logistic regression analysis showed that elevated serum HMGB1 level, thinner macular GCIPL thickness, and higher HY stage were independent risk factors for Parkinson's disease with cognitive impairment (PD-CI). The areas under the receiver operating characteristic curve (AUC) for the serum HMGB1 level and macular GCIPL thickness-based diagnosis of PD-MCI, PDD and PD-CI based on in patients with PD were 0.786 and 0.825, 0.915 and 0.856, 0.852 and 0.841, respectively. The AUC for the diagnosis of PD-MCI, PDD and PD-CI with serum HMGB1 level and GCIPL thickness combined were 0.869, 0.967 and 0.916, respectively. CONCLUSION: The macular GCIPL thickness and serum HMGB1 level are potential markers of cognitive impairment in PD patients, and their combination can significantly improve the accuracy of the diagnosis of cognitive impairment in PD.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Proteína HMGB1 , Enfermedad de Parkinson , Humanos , Cognición , Retina
12.
Lancet ; 401(10380): 917-927, 2023 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-36842439

RESUMEN

BACKGROUND: Reirradiation in standard fractionation for locally advanced recurrent nasopharyngeal carcinoma after a previous course of high-dose radiotherapy is often associated with substantial late toxicity, negating its overall benefit. We therefore aimed to investigate the efficacy and safety of hyperfractionation compared with standard fractionation in intensity-modulated radiotherapy. METHODS: This multicentre, randomised, open-label, phase 3 trial was done in three centres in Guangzhou, China. Eligible patients were aged 18-65 years with histopathologically confirmed undifferentiated or differentiated, non-keratinising, advanced locally recurrent nasopharyngeal carcinoma. Participants were randomly assigned (1:1) to either receive hyperfractionation (65 Gy in 54 fractions, given twice daily with an interfractional time interval of at least 6 h) or standard fractionation (60 Gy in 27 fractions, given once a day). Intensity-modulated radiotherapy was used in both groups. A computer program generated the assignment sequence and randomisation was stratified by treatment centre, recurrent tumour stage (T2-T3 vs T4), and recurrent nodal stage (N0 vs N1-N2), determined at the time of randomisation. The two primary endpoints were the incidence of severe late complications defined as the incidence of grade 3 or worse late radiation-induced complications occurring 3 months after the completion of radiotherapy until the latest follow-up in the safety population, and overall survival defined as the time interval from randomisation to death due to any cause in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02456506. FINDINGS: Between July 10, 2015, and Dec 23, 2019, 178 patients were screened for eligibility, 144 of whom were enrolled and randomly assigned to hyperfractionation or standard fractionation (n=72 in each group). 35 (24%) participants were women and 109 (76%) were men. After a median follow-up of 45·0 months (IQR 37·3-53·3), there was a significantly lower incidence of grade 3 or worse late radiation-induced toxicity in the hyperfractionation group (23 [34%] of 68 patients) versus the standard fractionation group (39 [57%] of 68 patients; between-group difference -23% [95% CI -39 to -7]; p=0·023). Patients in the hyperfractionation group had better 3-year overall survival than those in the standard fractionation group (74·6% [95% CI 64·4 to 84·8] vs 55·0% [43·4 to 66·6]; hazard ratio for death 0·54 [95% CI 0·33 to 0·88]; p=0·014). There were fewer grade 5 late complications in the hyperfractionation group (five [7%] nasal haemorrhage) than in the standard fractionation group (16 [24%], including two [3%] nasopharyngeal necrosis, 11 [16%] nasal haemorrhage, and three [4%] temporal lobe necrosis). INTERPRETATION: Hyperfractionated intensity-modulated radiotherapy could significantly decrease the rate of severe late complications and improve overall survival among patients with locally advanced recurrent nasopharyngeal carcinoma. Our findings suggest that hyperfractionated intensity-modulated radiotherapy could be used as the standard of care for these patients. FUNDING: Key-Area Research and Development of Guangdong Province, the National Natural Science Foundation of China, the Special Support Program for High-level Talents in Sun Yat-sen University Cancer Center, the Guangzhou Science and Technology Plan Project, and the National Ten Thousand Talents Program Science and Technology Innovation Leading Talents, Sun Yat-Sen University Clinical Research 5010 Program.


Asunto(s)
Neoplasias Nasofaríngeas , Radioterapia de Intensidad Modulada , Masculino , Humanos , Femenino , Carcinoma Nasofaríngeo/radioterapia , Radioterapia de Intensidad Modulada/efectos adversos , Recurrencia Local de Neoplasia/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Hemorragia
13.
Anal Chem ; 96(1): 347-354, 2024 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-38153415

RESUMEN

Sorting single cells from a population was of critical importance in areas such as cell line development and cell therapy. Image-based sorting is becoming a promising technique for the nonlabeling isolation of cells due to the capability of providing the details of cell morphology. This study reported the focusing of cells using microwell arrays and the following automatic size sorting based on the real-time recognition of cells. The simulation first demonstrated the converged streamlines to the symmetrical plane contributed to the focusing effect. Then, the influence of connecting microchannel, flowing length, particle size, and the sample flow rate on the focusing effect was experimentally analyzed. Both microspheres and cells could be aligned in a straight line at the Reynolds number (Re) of 0.027-0.187 and 0.027-0.08, respectively. The connecting channel was proved to drastically improve the focusing performance. Afterward, a tapered microwell array was utilized to focus sphere/cell spreading in a wide channel to a straight line. Finally, a custom algorithm was employed to identify and sort the size of microspheres/K562 cells with a throughput of 1 event/s and an accuracy of 97.8/97.1%. The proposed technique aligned cells to a straight line at low Reynolds numbers and greatly facilitated the image-activated sorting without the need for a high-speed camera or flow control components with high frequency. Therefore, it is of enormous application potential in the field of nonlabeled separation of single cells.


Asunto(s)
Tamaño de la Partícula , Humanos , Microesferas , Células K562 , Simulación por Computador
14.
Biochem Biophys Res Commun ; 722: 150157, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-38805789

RESUMEN

Age-associated adipose tissue (AT) dysfunction is multifactorial and often leads to detrimental health consequences. AT is highly vascularized and endothelial cells (ECs) has been recently identified as a key regulator in the homeostasis of AT. However, the alteration of cell composition in AT during aging and the communication between endothelial cells and adipocytes remain poorly understood. In this study, we take advantage of single nucleus RNA sequencing analysis, and discovered a group of FKBP5+ ECs specifically resident in aged AT. Of interest, FKBP5+ ECs exhibited the potential for endothelial-to-mesenchymal transition (EndoMT) and exhibited a critical role in regulating adipocytes. Furthermore, lineage tracing experiments demonstrated that ECs in aged AT tend to express FKBP5 and undergo EndoMT with progressive loss of endothelial marker. This study may provide a basis for a new mechanism of microvascular ECs-induced AT dysfunction during aging.


Asunto(s)
Tejido Adiposo , Envejecimiento , Células Endoteliales , Animales , Masculino , Ratones , Adipocitos/metabolismo , Adipocitos/citología , Tejido Adiposo/metabolismo , Tejido Adiposo/citología , Envejecimiento/metabolismo , Envejecimiento/genética , Núcleo Celular/metabolismo , Células Endoteliales/metabolismo , Transición Epitelial-Mesenquimal/genética , Perfilación de la Expresión Génica , Ratones Endogámicos C57BL , Análisis de la Célula Individual/métodos , Proteínas de Unión a Tacrolimus/metabolismo , Proteínas de Unión a Tacrolimus/genética , Transcriptoma
15.
Brief Bioinform ; 23(1)2022 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-34929730

RESUMEN

Protein-RNA interactions are of vital importance to a variety of cellular activities. Both experimental and computational techniques have been developed to study the interactions. Because of the limitation of the previous database, especially the lack of protein structure data, most of the existing computational methods rely heavily on the sequence data, with only a small portion of the methods utilizing the structural information. Recently, AlphaFold has revolutionized the entire protein and biology field. Foreseeably, the protein-RNA interaction prediction will also be promoted significantly in the upcoming years. In this work, we give a thorough review of this field, surveying both the binding site and binding preference prediction problems and covering the commonly used datasets, features and models. We also point out the potential challenges and opportunities in this field. This survey summarizes the development of the RNA-binding protein-RNA interaction field in the past and foresees its future development in the post-AlphaFold era.


Asunto(s)
Aprendizaje Profundo , Proteínas de Unión al ARN/química , ARN/química , ARN/metabolismo , Algoritmos , Sitios de Unión , Biología Computacional/métodos , Conformación Proteica , ARN/genética , Proteínas de Unión al ARN/metabolismo
16.
Brief Bioinform ; 23(5)2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-36089561

RESUMEN

We present a novel self-supervised Contrastive LEArning framework for single-cell ribonucleic acid (RNA)-sequencing (CLEAR) data representation and the downstream analysis. Compared with current methods, CLEAR overcomes the heterogeneity of the experimental data with a specifically designed representation learning task and thus can handle batch effects and dropout events simultaneously. It achieves superior performance on a broad range of fundamental tasks, including clustering, visualization, dropout correction, batch effect removal, and pseudo-time inference. The proposed method successfully identifies and illustrates inflammatory-related mechanisms in a COVID-19 disease study with 43 695 single cells from peripheral blood mononuclear cells.


Asunto(s)
COVID-19 , ARN , COVID-19/genética , Análisis por Conglomerados , Análisis de Datos , Humanos , Leucocitos Mononucleares , RNA-Seq , Análisis de Secuencia de ARN/métodos
17.
J Transl Med ; 22(1): 792, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39198815

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortality. Although multi-kinase inhibitors can prolong the overall survival of late-stage HCC patients, the emergence of drug resistance diminishes these benefits, ultimately resulting in treatment failure. Therefore, there is an urgent need for novel and effective drugs to impede the progression of liver cancer. METHODS: This study employed a concentration gradient increment method to establish acquired sorafenib or regorafenib-resistant SNU-449 cells. Cell viability was assessed using the cell counting kit-8 assay. A library of 793 bioactive small molecules related to metabolism screened compounds targeting both parental and drug-resistant cells. The screened compounds will be added to both the HCC parental cells and the drug-resistant cells, followed by a comprehensive assessment. Intracellular adenosine triphosphate (ATP) levels were quantified using kits. Flow cytometry was applied to assess cell apoptosis and reactive oxygen species (ROS). Real-time quantitative PCR studied relative gene expression, and western blot analysis assessed protein expression changes in HCC parental and drug-resistant cells. A xenograft model in vivo evaluated Mito-LND and (E)-Akt inhibitor-IV effects on liver tumors, with hematoxylin and eosin staining for tissue structure and immunohistochemistry staining for endoplasmic reticulum stress protein expression. RESULTS: From the compound library, we screened out two novel compounds, Mito-LND and (E)-Akt inhibitor-IV, which could potently kill both parental cells and drug-resistant cells. Mito-LND could significantly suppress proliferation and induce apoptosis in HCC parental and drug-resistant cells by upregulating glycolytic intermediates and downregulating those of the tricarboxylic acid (TCA) cycle, thereby decreasing ATP production and increasing ROS. (E)-Akt inhibitor-IV achieved comparable results by reducing glycolytic intermediates, increasing TCA cycle intermediates, and decreasing ATP synthesis and ROS levels. Both compounds trigger apoptosis in HCC cells through the interplay of the AMPK/MAPK pathway and the endoplasmic reticulum stress response. In vivo assays also showed that these two compounds could significantly inhibit the growth of HCC cells and induce endoplasmic reticulum stress. CONCLUSION: Through high throughput screening, we identified that Mito-LND and (E)-Akt inhibitor-IV are two novel compounds against both parental and drug-resistant HCC cells, which could offer new strategies for HCC patients.


Asunto(s)
Apoptosis , Carcinoma Hepatocelular , Estrés del Retículo Endoplásmico , Neoplasias Hepáticas , Ratones Desnudos , Proteínas Proto-Oncogénicas c-akt , Especies Reactivas de Oxígeno , Ensayos Antitumor por Modelo de Xenoinjerto , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Estrés del Retículo Endoplásmico/efectos de los fármacos , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/metabolismo , Humanos , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral , Animales , Proteínas Proto-Oncogénicas c-akt/metabolismo , Apoptosis/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Ratones Endogámicos BALB C , Adenosina Trifosfato/metabolismo , Ratones , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos
18.
J Anat ; 245(3): 377-391, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38720634

RESUMEN

Characterizing the suture morphological variation is a crucial step to investigate the influence of sutures on infant head biomechanics. This study aimed to establish a comprehensive quantitative framework for accurately capturing the cranial suture and fontanelle morphologies in infants. A total of 69 CT scans of 2-4 month-old infant heads were segmented to identify semilandmarks at the borders of cranial sutures and fontanelles. Morphological characteristics, including length, width, sinuosity index (SI), and surface area, were measured. For this, an automatic method was developed to determine the junction points between sutures and fontanelles, and thin-plate-spline (TPS) was utilized for area calculation. Different dimensionality reduction methods were compared, including nonlinear and linear principal component analysis (PCA), as well as deep-learning-based variational autoencoder (VAE). Finally, the significance of various covariates was analyzed, and regression analysis was performed to establish a statistical model relating morphological parameters with global parameters. This study successfully developed a quantitative morphological framework and demonstrate its application in quantifying morphologies of infant sutures and fontanelles, which were shown to significantly relate to global parameters of cranial size, suture SI, and surface area for infants aged 2-4 months. The developed framework proved to be reliable and applicable in extracting infant suture morphology features from CT scans. The demonstrated application highlighted its potential to provide valuable insights into the morphologies of infant cranial sutures and fontanelles, aiding in the diagnosis of suture-related skull fractures. Infant suture, Infant fontanelle, Morphological variation, Morphology analysis framework, Statistical model.


Asunto(s)
Fontanelas Craneales , Suturas Craneales , Tomografía Computarizada por Rayos X , Humanos , Suturas Craneales/diagnóstico por imagen , Fontanelas Craneales/diagnóstico por imagen , Fontanelas Craneales/anatomía & histología , Lactante , Tomografía Computarizada por Rayos X/métodos , Masculino , Femenino
19.
Blood ; 139(11): 1619-1630, 2022 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-35030255

RESUMEN

The Kasabach-Merritt phenomenon (KMP) in kaposiform hemangioendothelioma (KHE) is characterized by life-threatening thrombocytopenia and consumptive coagulopathy. This study compared the efficacy and safety of sirolimus plus prednisolone vs sirolimus monotherapy as treatment strategies for KHE with KMP in the largest cohort to date. Participants were randomized to receive either sirolimus in combination with a short course of prednisolone or sirolimus monotherapy for at least 12 months. The primary outcome was defined as achievement of a durable platelet response (platelet count >100 × 109/L) at week 4. Participants completed efficacy assessments 2 years after the initial treatment. At week 4, a durable platelet response was achieved by 35 of 37 patients given sirolimus and prednisolone compared with 24 of 36 patients given sirolimus monotherapy (difference 27.9%; 95% confidence interval, 10.0-44.7). Compared with the sirolimus monotherapy group, the combination treatment group showed improvements in terms of measures of durable platelet responses at all points during the initial 3-week treatment period, median platelet counts during weeks 1 to 4, increased numbers of patients achieving fibrinogen stabilization at week 4, and objective lesion responses at month 12. Patients receiving combination therapy had fewer blood transfusions and a lower total incidence of disease sequelae than patients receiving sirolimus alone. The frequencies of total adverse events and grade 3-4 adverse events during treatment were similar in both groups. The responses seen in patients with KHE with KMP were profound and encouraging, suggesting that sirolimus plus prednisolone should be considered a valid treatment of KHE with KMP. This trial was registered at www.clinicaltrials.gov as #NCT03188068.


Asunto(s)
Hemangioendotelioma , Síndrome de Kasabach-Merritt , Sarcoma de Kaposi , Hemangioendotelioma/complicaciones , Hemangioendotelioma/tratamiento farmacológico , Hemangioendotelioma/patología , Humanos , Lactante , Síndrome de Kasabach-Merritt/complicaciones , Síndrome de Kasabach-Merritt/tratamiento farmacológico , Síndrome de Kasabach-Merritt/patología , Prednisolona/uso terapéutico , Sarcoma de Kaposi/complicaciones , Sirolimus/uso terapéutico
20.
Sex Transm Infect ; 100(5): 264-270, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-38789266

RESUMEN

OBJECTIVE: Sub-Saharan Africa is one of the regions with the highest burdens of HIV and hepatitis B virus (HBV), but data on the impact of antiretroviral therapy (ART) on HBV DNA suppression is limited. In this study, we aimed to determine the prevalence and associated factors of a positive hepatitis B surface antigen (HBsAg) among people living with HIV, and assess the suppression of ART on HBV replication in people living with HIV in Sierra Leone. METHODS: A cross-sectional study was designed to recruit people living with HIV aged 18 years or older in ten public hospitals in Sierra Leone between August 2022 and January 2023. Statistical analyses were performed using R software. Logistic regression analysis was used to assess factors independently associated with positive HBsAg and HBV DNA suppression. RESULTS: Of the 3106 people living with HIV recruited in this study, 2311 (74.4%) were women. The median age was 36 years, 166 (5.3%) had serological evidence of HBV vaccination. The overall prevalence of HBsAg positivity was 12.0% (95% CI: 10.9% to 13.2%). Male sex (adjusted OR (aOR) 2.11, 95% CI: 1.67 to 2.68; p<0.001) and being separated (aOR 1.83, 95% CI: 1.06 to 3.16, p=0.031; reference group: being married) were independent predictors of HBsAg seropositivity. Among 331 people living with HIV and HBV receiving ART, 242 (73.1%) achieved HBV DNA suppression (below 20 IU/mL). HBV suppression rate was higher in HIV-virally suppressed patients than those with unsuppressed HIV viral load (p<0.001). In addition, the male sex was more likely to have unsuppressed HBV DNA (aOR 1.17, 95% CI: 1.17 to 3.21; p=0.010). CONCLUSIONS: We reported a high prevalence of HBsAg seropositivity and low HBV immunisation coverage in people living with HIV in Sierra Leone. In addition, we observed that ART can efficiently result in a viral suppression rate of HBV infection. Therefore, achieving the global target of eliminating HBV infection by 2030 requires accelerated access to care for people living with HIV and HBV, including HBV testing, antiviral treatment and hepatitis B vaccination.


Asunto(s)
Infecciones por VIH , Antígenos de Superficie de la Hepatitis B , Virus de la Hepatitis B , Hepatitis B , Humanos , Masculino , Femenino , Adulto , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Infecciones por VIH/virología , Sierra Leona/epidemiología , Estudios Transversales , Prevalencia , Hepatitis B/epidemiología , Hepatitis B/tratamiento farmacológico , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Persona de Mediana Edad , Carga Viral , Adulto Joven , ADN Viral/sangre , Adolescente , Coinfección/epidemiología , Coinfección/virología , Fármacos Anti-VIH/uso terapéutico , Antirretrovirales/uso terapéutico
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