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1.
Cell ; 180(5): 1018-1032.e16, 2020 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-32109416

RESUMEN

The ability to identify single-nucleotide mutations is critical for probing cell biology and for precise detection of disease. However, the small differences in hybridization energy provided by single-base changes makes identification of these mutations challenging in living cells and complex reaction environments. Here, we report a class of de novo-designed prokaryotic riboregulators that provide ultraspecific RNA detection capabilities in vivo and in cell-free transcription-translation reactions. These single-nucleotide-specific programmable riboregulators (SNIPRs) provide over 100-fold differences in gene expression in response to target RNAs differing by a single nucleotide in E. coli and resolve single epitranscriptomic marks in vitro. By exploiting the programmable SNIPR design, we implement an automated design algorithm to develop riboregulators for a range of mutations associated with cancer, drug resistance, and genetic disorders. Integrating SNIPRs with portable paper-based cell-free reactions enables convenient isothermal detection of cancer-associated mutations from clinical samples and identification of Zika strains through unambiguous colorimetric reactions.


Asunto(s)
Epigenómica , Polimorfismo de Nucleótido Simple/genética , ARN/genética , Transcriptoma/genética , Resistencia a Medicamentos/genética , Escherichia coli/genética , Regulación de la Expresión Génica/genética , Humanos , Mutación/genética , Neoplasias/genética , Conformación de Ácido Nucleico , Células Procariotas/metabolismo , Biología Sintética , Virus Zika/genética , Virus Zika/aislamiento & purificación , Virus Zika/patogenicidad
3.
Nat Methods ; 21(2): 247-258, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38200227

RESUMEN

RNA-binding proteins (RBPs) regulate diverse cellular processes by dynamically interacting with RNA targets. However, effective methods to capture both stable and transient interactions between RBPs and their RNA targets are still lacking, especially when the interaction is dynamic or samples are limited. Here we present an assay of reverse transcription-based RBP binding site sequencing (ARTR-seq), which relies on in situ reverse transcription of RBP-bound RNAs guided by antibodies to identify RBP binding sites. ARTR-seq avoids ultraviolet crosslinking and immunoprecipitation, allowing for efficient and specific identification of RBP binding sites from as few as 20 cells or a tissue section. Taking advantage of rapid formaldehyde fixation, ARTR-seq enables capturing the dynamic RNA binding by RBPs over a short period of time, as demonstrated by the profiling of dynamic RNA binding of G3BP1 during stress granule assembly on a timescale as short as 10 minutes.


Asunto(s)
ARN , Transcripción Reversa , ARN/genética , ARN/metabolismo , ADN Helicasas/metabolismo , Proteínas de Unión a Poli-ADP-Ribosa/genética , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo , ARN Helicasas/genética , ARN Helicasas/metabolismo , Proteínas con Motivos de Reconocimiento de ARN/genética , Proteínas con Motivos de Reconocimiento de ARN/metabolismo , Proteínas de Unión al ARN/metabolismo , Sitios de Unión/genética , Unión Proteica
4.
Nat Chem Biol ; 19(11): 1384-1393, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37400536

RESUMEN

Compact CRISPR-Cas systems offer versatile treatment options for genetic disorders, but their application is often limited by modest gene-editing activity. Here we present enAsCas12f, an engineered RNA-guided DNA endonuclease up to 11.3-fold more potent than its parent protein, AsCas12f, and one-third of the size of SpCas9. enAsCas12f shows higher DNA cleavage activity than wild-type AsCas12f in vitro and functions broadly in human cells, delivering up to 69.8% insertions and deletions at user-specified genomic loci. Minimal off-target editing is observed with enAsCas12f, suggesting that boosted on-target activity does not impair genome-wide specificity. We determine the cryo-electron microscopy (cryo-EM) structure of the AsCas12f-sgRNA-DNA complex at a resolution of 2.9 Å, which reveals dimerization-mediated substrate recognition and cleavage. Structure-guided single guide RNA (sgRNA) engineering leads to sgRNA-v2, which is 33% shorter than the full-length sgRNA, but with on par activity. Together, the engineered hypercompact AsCas12f system enables robust and faithful gene editing in mammalian cells.


Asunto(s)
Edición Génica , ARN Guía de Sistemas CRISPR-Cas , Animales , Humanos , Microscopía por Crioelectrón , Sistemas CRISPR-Cas/genética , ADN/química , Mamíferos/genética
5.
Mol Psychiatry ; 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38336841

RESUMEN

Antipsychotic-induced weight gain (AIWG) is a common side effect of antipsychotic medication and may contribute to diabetes and coronary heart disease. To expand the unclear genetic mechanism underlying AIWG, we conducted a two-stage genome-wide association study in Han Chinese patients with schizophrenia. The study included a discovery cohort of 1936 patients and a validation cohort of 534 patients, with an additional 630 multi-ancestry patients from the CATIE study for external validation. We applied Mendelian randomization (MR) analysis to investigate the relationship between AIWG and antipsychotic-induced lipid changes. Our results identified two novel genome-wide significant loci associated with AIWG: rs10422861 in PEPD (P = 1.373 × 10-9) and rs3824417 in PTPRD (P = 3.348 × 10-9) in Chinese Han samples. The association of rs10422861 was validated in the European samples. Fine-mapping and functional annotation revealed that PEPD and PTPRD are potentially causal genes for AIWG, with their proteins being prospective therapeutic targets. Colocalization analysis suggested that AIWG and type 2 diabetes (T2D) shared a causal variant in PEPD. Polygenic risk scores (PRSs) for AIWG and T2D significantly predicted AIWG in multi-ancestry samples. Furthermore, MR revealed a risky causal effect of genetically predicted changes in low-density lipoprotein cholesterol (P = 7.58 × 10-4) and triglycerides (P = 2.06 × 10-3) caused by acute-phase of antipsychotic treatment on AIWG, which had not been previously reported. Our model, incorporating antipsychotic-induced lipid changes, PRSs, and clinical predictors, significantly predicted BMI percentage change after 6-month antipsychotic treatment (AUC = 0.79, R2 = 0.332). Our results highlight that the mechanism of AIWG involves lipid pathway dysfunction and may share a genetic basis with T2D through PEPD. Overall, this study provides new insights into the pathogenesis of AIWG and contributes to personalized treatment of schizophrenia.

6.
Cereb Cortex ; 34(3)2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38466117

RESUMEN

Speech disorders are associated with different degrees of functional and structural abnormalities. However, the abnormalities associated with specific disorders, and the common abnormalities shown by all disorders, remain unclear. Herein, a meta-analysis was conducted to integrate the results of 70 studies that compared 1843 speech disorder patients (dysarthria, dysphonia, stuttering, and aphasia) to 1950 healthy controls in terms of brain activity, functional connectivity, gray matter, and white matter fractional anisotropy. The analysis revealed that compared to controls, the dysarthria group showed higher activity in the left superior temporal gyrus and lower activity in the left postcentral gyrus. The dysphonia group had higher activity in the right precentral and postcentral gyrus. The stuttering group had higher activity in the right inferior frontal gyrus and lower activity in the left inferior frontal gyrus. The aphasia group showed lower activity in the bilateral anterior cingulate gyrus and left superior frontal gyrus. Across the four disorders, there were concurrent lower activity, gray matter, and fractional anisotropy in motor and auditory cortices, and stronger connectivity between the default mode network and frontoparietal network. These findings enhance our understanding of the neural basis of speech disorders, potentially aiding clinical diagnosis and intervention.


Asunto(s)
Afasia , Corteza Auditiva , Disfonía , Tartamudeo , Humanos , Disartria , Funciones de Verosimilitud , Trastornos del Habla
7.
J Cell Mol Med ; 28(10): e18381, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38780509

RESUMEN

Peritoneal fibrosis is a common pathological response to long-term peritoneal dialysis (PD) and a major cause for PD discontinuation. Understanding the cellular and molecular mechanisms underlying the induction and progression of peritoneal fibrosis is of great interest. In our study, in vitro study revealed that signal transducer and activator of transcription 3 (STAT3) is a key factor in fibroblast activation and extracellular matrix (ECM) synthesis. Furthermore, STAT3 induced by IL-6 trans-signalling pathway mediate the fibroblasts of the peritoneal stroma contributed to peritoneal fibrosis. Inhibition of STAT3 exerts an antifibrotic effect by attenuating fibroblast activation and ECM production with an in vitro co-culture model. Moreover, STAT3 plays an important role in the peritoneal fibrosis in an animal model of peritoneal fibrosis developed in mice. Blocking STAT3 can reduce the peritoneal morphological changes induced by chlorhexidine gluconate. In conclusion, our findings suggested STAT3 signalling played an important role in peritoneal fibrosis. Therefore, blocking STAT3 might become a potential treatment strategy in peritoneal fibrosis.


Asunto(s)
Ácidos Aminosalicílicos , Fibroblastos , Fibrosis Peritoneal , Fenotipo , Factor de Transcripción STAT3 , Transducción de Señal , Fibrosis Peritoneal/metabolismo , Fibrosis Peritoneal/patología , Fibrosis Peritoneal/etiología , Fibrosis Peritoneal/genética , Factor de Transcripción STAT3/metabolismo , Animales , Fibroblastos/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/patología , Ratones , Ácidos Aminosalicílicos/farmacología , Transducción de Señal/efectos de los fármacos , Modelos Animales de Enfermedad , Peritoneo/patología , Peritoneo/metabolismo , Interleucina-6/metabolismo , Matriz Extracelular/metabolismo , Masculino , Ratones Endogámicos C57BL , Humanos , Clorhexidina/análogos & derivados , Clorhexidina/farmacología , Diálisis Peritoneal/efectos adversos , Bencenosulfonatos
8.
J Am Chem Soc ; 146(6): 4178-4186, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38301245

RESUMEN

DNA origami, comprising a long folded DNA scaffold and hundreds of linear DNA staple strands, has been developed to construct various sophisticated structures, smart devices, and drug delivery systems. However, the size and diversity of DNA origami are usually constrained by the length of DNA scaffolds themselves. Herein, we report a new paradigm of scaling up DNA origami assembly by introducing a novel branched staple concept. Owing to their covalent characteristics, the chemically conjugated branched DNA staples we describe here can be directly added to a typical DNA origami assembly system to obtain super-DNA origami with a predefined number of origami tiles in one pot. Compared with the traditional two-step coassembly system (yields <10%), a much greater yield (>80%) was achieved using this one-pot strategy. The diverse superhybrid DNA origami with the combination of different origami tiles can be also efficiently obtained by the hybrid branched staples. Furthermore, the branched staples can be successfully employed as the effective molecular glues to stabilize micrometer-scale, super-DNA origami arrays (e.g., 10 × 10 array of square origami) in high yields, paving the way to bridge the nanoscale precision of DNA origami with the micrometer-scale device engineering. This rationally developed assembly strategy for super-DNA origami based on chemically conjugated branched staples presents a new avenue for the development of multifunctional DNA origami-based materials.


Asunto(s)
Nanoestructuras , Nanoestructuras/química , Nanotecnología , ADN/química , Análisis de Secuencia por Matrices de Oligonucleótidos , Conformación de Ácido Nucleico
9.
J Am Chem Soc ; 146(4): 2736-2747, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38227768

RESUMEN

Barocaloric effects─solid-state thermal changes induced by the application and removal of hydrostatic pressure─offer the potential for energy-efficient heating and cooling without relying on volatile refrigerants. Here, we report that dialkylammonium halides─organic salts featuring bilayers of alkyl chains templated through hydrogen bonds to halide anions─display large, reversible, and tunable barocaloric effects near ambient temperature. The conformational flexibility and soft nature of the weakly confined hydrocarbons give rise to order-disorder phase transitions in the solid state that are associated with substantial entropy changes (>200 J kg-1 K-1) and high sensitivity to pressure (>24 K kbar-1), the combination of which drives strong barocaloric effects at relatively low pressures. Through high-pressure calorimetry, X-ray diffraction, and Raman spectroscopy, we investigate the structural factors that influence pressure-induced phase transitions of select dialkylammonium halides and evaluate the magnitude and reversibility of their barocaloric effects. Furthermore, we characterize the cyclability of thin-film samples under aggressive conditions (heating rate of 3500 K s-1 and over 11,000 cycles) using nanocalorimetry. Taken together, these results establish dialkylammonium halides as a promising class of pressure-responsive thermal materials.

10.
J Am Chem Soc ; 146(7): 4557-4569, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38345667

RESUMEN

Intelligent utilization of the anionic redox reaction (ARR) in Li-rich cathodes is an advanced strategy for the practical implementation of next-generation high-energy-density rechargeable batteries. However, due to the intrinsic complexity of ARR (e.g., nucleophilic attacks), the instability of the cathode-electrolyte interphase (CEI) on a Li-rich cathode presents more challenges than typical high-voltage cathodes. Here, we manipulate CEI interfacial engineering by introducing an all-fluorinated electrolyte and exploiting its interaction with the nucleophilic attack to construct a gradient CEI containing a pair of fluorinated layers on a Li-rich cathode, delivering enhanced interfacial stability. Negative/detrimental nucleophilic electrolyte decomposition has been efficiently evolved to further reinforce CEI fabrication, resulting in the construction of LiF-based indurated outer shield and fluorinated polymer-based flexible inner sheaths. Gradient interphase engineering dramatically improved the capacity retention of the Li-rich cathode from 43 to 71% after 800 cycles and achieved superior cycling stability in anode-free and pouch-type full cells (98.8% capacity retention, 220 cycles), respectively.

11.
Cogn Affect Behav Neurosci ; 24(3): 517-526, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38273105

RESUMEN

Sleep deprivation (SD) negatively affects many cognitive functions, such as language performance. However, what remains unclear is whether and how SD affects the language-related brain network based on gender and age differences. The current study of 86 healthy adults used resting-state functional magnetic resonance imaging (rs-fMRI) to measure language-related functional connectivity after full sleep or partial SD. Gender and age differences in functional connectivity were assessed across four linguistic aspects: phonetics, morphology, semantics, and syntax. The results showed that SD can affect the connectivity status of language-related brain networks, especially syntax-related networks. Furthermore, the influence of SD on the functional connectivity in language-related networks differed between male and female groups, and between younger and older groups. Specifically, there were gender differences in the temporal association cortex and age differences in the parietal association cortex, during full sleep versus partial SD. These findings highlight changes in the brain's functional connectivity in response to SD as a potential source of gender and age differences in brain function.


Asunto(s)
Mapeo Encefálico , Encéfalo , Lenguaje , Imagen por Resonancia Magnética , Caracteres Sexuales , Privación de Sueño , Humanos , Masculino , Femenino , Adulto , Privación de Sueño/fisiopatología , Privación de Sueño/diagnóstico por imagen , Adulto Joven , Encéfalo/fisiopatología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Vías Nerviosas/fisiopatología , Vías Nerviosas/fisiología , Vías Nerviosas/diagnóstico por imagen , Persona de Mediana Edad , Envejecimiento/fisiología , Adolescente
12.
BMC Med ; 22(1): 146, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38561734

RESUMEN

BACKGROUND: Childhoods in urban or rural environments may differentially affect the risk of neuropsychiatric disorders, possibly through memory processing and neural response to emotional stimuli. Genetic factors may not only influence individuals' choices of residence but also modulate how the living environment affects responses to episodic memory. METHODS: We investigated the effects of childhood urbanicity on episodic memory in 410 adults (discovery sample) and 72 adults (replication sample) with comparable socioeconomic statuses in Beijing, China, distinguishing between those with rural backgrounds (resided in rural areas before age 12 and relocated to urban areas at or after age 12) and urban backgrounds (resided in cities before age 12). We examined the effect of childhood urbanicity on brain function across encoding and retrieval sessions using an fMRI episodic memory paradigm involving the processing of neutral or aversive pictures. Moreover, genetic association analyses were conducted to understand the potential genetic underpinnings that might contribute to memory processing and neural mechanisms influenced by early-life urban or rural environments. RESULTS: Episodic memory retrieval accuracy for more difficult neutral stimuli was similar between those with urban and rural childhoods, whereas aversive stimuli elicited higher retrieval accuracy in the urban group (P = 0.023). For aversive stimuli, subjects with urban childhood had relatively decreased engagement of the striatum at encoding and decreased engagement of the hippocampus at retrieval. This more efficient striatal encoding of aversive stimuli in those with urban childhoods was associated with common variation in neurotrophic tyrosine kinase receptor type 2 (NTRK2) (right striatum: P = 1.58×10-6). These findings were confirmed in the replication sample. CONCLUSIONS: We suggest that this differential striatal processing of aversive stimuli observed in individuals with urban or rural childhoods may represent mechanisms by which childhood urbanicity may affect brain circuits, heightening behavioral responses to negative stressors associated with urban environments. NTRK2-associated neural processes in the striatum may play a role in these processes.


Asunto(s)
Memoria Episódica , Adulto , Niño , Humanos , Mapeo Encefálico , Emociones/fisiología , Hipocampo , Imagen por Resonancia Magnética , Receptor trkB
13.
Small ; 20(9): e2307585, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37849034

RESUMEN

The combination of multiple orthogonal interactions enables hierarchical complexity in self-assembled nanoscale materials. Here, efficient supramolecular polymerization of DNA origami nanostructures is demonstrated using a multivalent display of small molecule host-guest interactions. Modification of DNA strands with cucurbit[7]uril (CB[7]) and its adamantane guest, yielding a supramolecular complex with an affinity of order 1010 m-1 , directs hierarchical assembly of origami monomers into 1D nanofibers. This affinity regime enables efficient polymerization; a lower-affinity ß-cyclodextrin-adamantane complex does not promote extended structures at a similar valency. Finally, the utility of the high-affinity CB[7]-adamantane interactions is exploited to enable responsive enzymatic actuation of origami nanofibers assembled using peptide linkers. This work demonstrates the power of high-affinity CB[7]-guest recognition as an orthogonal axis to drive self-assembly in DNA nanotechnology.


Asunto(s)
Adamantano , Nanofibras , Nanoestructuras , Nanotecnología , ADN
14.
Metab Eng ; 81: 210-226, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38142854

RESUMEN

Streptomyces has an extensive array of bioactive secondary metabolites (SMs). Nevertheless, devising a framework for the heterologous production of these SMs remains challenging. We here reprogrammed a versatile plug-and-play Streptomyces super-chassis and established a universal pipeline for production of diverse SMs via understanding of the inherent pleiotropic effects of ethanol shock on jadomycin production in Streptomyces venezuelae. We initially identified and characterized a set of multiplex targets (afsQ1, bldD, bldA, and miaA) that contribute to SM (jadomycin) production when subjected to ethanol shock. Subsequently, we developed an ethanol-induced orthogonal amplification system (EOAS), enabling dynamic and precise control over targets. Ultimately, we integrated these multiplex targets into functional units governed by the EOAS, generating a universal and plug-and-play Streptomyces super-chassis. In addition to achieving the unprecedented titer and yield of jadomycin B, we also evidenced the potential of this super-chassis for production of diverse heterologous SMs, including antibiotic oxytetracycline, anticancer drug doxorubicins, agricultural herbicide thaxtomin A, and plant growth regulator guvermectin, all with the yields of >10 mg/g glucose in a simple mineral medium. Given that the production of SMs all required complexed medium and the cognate yields were usually much lower, our achievement of using a universal super-chassis and engineering pipeline in a simple mineral medium is promising for convenient heterologous production of SMs.


Asunto(s)
Adenosina/análogos & derivados , Streptomyces , Streptomyces/genética , Streptomyces/metabolismo , Antibacterianos , Etanol/metabolismo , Minerales/metabolismo , Minerales/farmacología
15.
Ann Surg Oncol ; 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38520581

RESUMEN

BACKGROUND: Noninvasively and accurately predicting subcarinal lymph node metastasis (SLNM) for patients with non-small cell lung cancer (NSCLC) remains challenging. This study was designed to develop and validate a tumor and subcarinal lymph nodes (tumor-SLNs) dual-region computed tomography (CT) radiomics model for predicting SLNM in NSCLC. METHODS: This retrospective study included NSCLC patients who underwent lung resection and SLNs dissection between January 2017 and December 2020. The radiomic features of the tumor and SLNs were extracted from preoperative CT, respectively. Ninety machine learning (ML) models were developed based on tumor region, SLNs region, and tumor-SLNs dual-region. The model performance was assessed by the area under the curve (AUC) and validated internally by fivefold cross-validation. RESULTS: In total, 202 patients were included in this study. ML models based on dual-region radiomics showed good performance for SLNM prediction, with a median AUC of 0.794 (range, 0.686-0.880), which was superior to those of models based on tumor region (median AUC, 0.746; range, 0.630-0.811) and SLNs region (median AUC, 0.700; range, 0.610-0.842). The ML model, which is developed by using the naive Bayes algorithm and dual-region features, had the highest AUC of 0.880 (range of cross-validation, 0.825-0.937) among all ML models. The optimal logistic regression model was inferior to the optimal ML model for predicting SLNM, with an AUC of 0.727. CONCLUSIONS: The CT radiomics showed the potential for accurately predicting SLNM in NSCLC patients. The ML model with dual-region radiomic features has better performance than the logistic regression or single-region models.

16.
Opt Express ; 32(4): 6748-6764, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439373

RESUMEN

Data rate and security are essential performance metrics for passive optical networks (PON). However, existing optical access networks lack standardized metrics to evaluate rate and security performance uniformly. This paper introduces a high-speed and security joint optimization scheme for optical access networks using convex optimization. Evaluation metrics for data rate and security performance in PON are established. According to the evaluation metrics, the security optimization objective function Us, high-speed optimization objective function GMI, and high-speed security joint-optimization objective function Hs are established. An optimization problem is formulated to maximize weighted rate and security indicators, factoring in constraints such as maximum power, probability, amplifier capacity, normalized mutual information, and key and frame lengths. An alternating optimization method is applied to iteratively address sub-problems by exploiting successive convex approximations and differences of convex functions. This transforms non-convex sub-problems into convex optimizations. Experimental results highlight notable improvements in objective function values, confirming the effectiveness of the proposed high-speed security optimization algorithm for optical access networks.

17.
Opt Express ; 32(6): 9958-9966, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38571219

RESUMEN

In this study, a three-dimensional (3D) laser micromachining system with an integrated sub-100 nm resolution in-situ measurement system was proposed. The system used the same femtosecond laser source for in-situ measurement and machining, avoiding errors between the measurement and the machining positions. It could measure the profile of surfaces with an inclination angle of less than 10°, and the measurement resolution was greater than 100 nm. Consequently, the precise and stable movement of the laser focus could be controlled, enabling highly stable 3D micromachining. The results showed that needed patterns could be machined on continuous surfaces using the proposed system. The proposed machining system is of great significance for broadening the application scenarios of laser machining.

18.
Opt Lett ; 49(4): 850-853, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38359198

RESUMEN

Lithium niobate (LN) crystal plays important roles in future integrated photonics, but it is still a great challenge to efficiently fabricate three-dimensional micro-/nanostructures on it. Here, a femtosecond laser direct writing-assisted liquid back-etching technology (FsLDW-LBE) is proposed to achieve the three-dimensional (3D) microfabrication of lithium niobate (LN) with high surface quality (Ra = 0.422 nm). Various 3D structures, such as snowflakes, graphic arrays, criss-cross arrays, and helix arrays, have been successfully fabricated on the surface of LN crystals. As an example, a microcone array was fabricated on LN crystals, which showed a strong second harmonic signal enhancement with up to 12 times bigger than the flat lithium niobate. The results indicate that the method provides a new approach for the microfabrication of lithium niobate crystals for nonlinear optics.

19.
Opt Lett ; 49(4): 911-914, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38359214

RESUMEN

In this Letter, a method for the fabrication of bifocal lenses is presented by combining surface ablation and bulk modification in a single laser exposure followed by the wet etching processing step. The intensity of a single femtosecond laser pulse was modulated axially into two foci with a designed computer-generated hologram (CGH). Such pulse simultaneously induced an ablation region on the surface and a modified volume inside the fused silica. After etching in hydrofluoric acid (HF), the two exposed regions evolved into a bifocal lens. The area ratio (diameter) of the two lenses can be flexibly adjusted via control of the pulse energy distribution through the CGH. Besides, bifocal lenses with a center offset as well as convex lenses were obtained by a replication technique. This method simplifies the fabrication of micro-optical elements and opens a highly efficient and simple pathway for complex optical surfaces and integrated imaging systems.

20.
BMC Cancer ; 24(1): 22, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38166647

RESUMEN

OBJECTIVE: To evaluate the efficacy and safety of regorafenib monotherapy or in combination with immune-checkpoint inhibitor while treating Chinese patients with metastatic colorectal cancer (mCRC): a real-world study. METHODS: The data of patients with metastatic colorectal cancer who received regorafenib-containing regimen as the third or later line treatment at ten Chinese hospitals from Aug 2017 to Jun 2020 were retrospectively analyzed, including dosing details, survival data as well as adverse events. Survival analysis was further performed for patients administrated with regorafenib monotherapy and combined with an immune-checkpoint inhibitor based on Kaplan-Meier and Cox regression methods. The primary endpoint was overall survival. RESULTS: A total of 537 patients were included with a median age of 61, among whom 376 received regorafenib monotherapy and 245 received regorafenib combined with immune-checkpoint inhibitors. The clinicopathological characteristics of the two groups at baseline were mainly balanced. No significant difference in progression-free survival (PFS) was observed in patients receiving regorafenib monotherapy or combination therapy (3.8 vs. 5.5 months, p = 0.170). In contrast, patients receiving combination therapy had a more prolonged overall survival (OS) than those receiving regorafenib monotherapy (13.5 vs. 10.0 months, p = 0.001). The treatment regimen and regorafenib dosage were significant prognostic factors in the multivariate analysis. Significant benefits in PFS and OS were achieved in KRAS mutant and anti-angiogenesis treatment-naïve subgroups receiving combination therapy compared to monotherapy. No apparent increase was recorded in treatment-related adverse events in patients receiving combination therapy. CONCLUSION: Regorafenib plus an immune-checkpoint inhibitor has already been a widely adopted strategy in the later-line treatment for mCRC in the real world. The combination therapy yielded a significantly prolonged overall survival than regorafenib alone, with a manageable safety profile in Chinese patients, and warrants further investigation. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04835324. Registered 6th April 2021.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Neoplasias del Recto , Humanos , Estudios Retrospectivos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Piridinas/efectos adversos , Compuestos de Fenilurea/efectos adversos
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