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1.
Nature ; 610(7933): 661-666, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36198794

RESUMO

Networks of optical clocks find applications in precise navigation1,2, in efforts to redefine the fundamental unit of the 'second'3-6 and in gravitational tests7. As the frequency instability for state-of-the-art optical clocks has reached the 10-19 level8,9, the vision of a global-scale optical network that achieves comparable performances requires the dissemination of time and frequency over a long-distance free-space link with a similar instability of 10-19. However, previous attempts at free-space dissemination of time and frequency at high precision did not extend beyond dozens of kilometres10,11. Here we report time-frequency dissemination with an offset of 6.3 × 10-20 ± 3.4 × 10-19 and an instability of less than 4 × 10-19 at 10,000 s through a free-space link of 113 km. Key technologies essential to this achievement include the deployment of high-power frequency combs, high-stability and high-efficiency optical transceiver systems and efficient linear optical sampling. We observe that the stability we have reached is retained for channel losses up to 89 dB. The technique we report can not only be directly used in ground-based applications, but could also lay the groundwork for future satellite time-frequency dissemination.

2.
Nature ; 589(7841): 214-219, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33408416

RESUMO

Quantum key distribution (QKD)1,2 has the potential to enable secure communication and information transfer3. In the laboratory, the feasibility of point-to-point QKD is evident from the early proof-of-concept demonstration in the laboratory over 32 centimetres4; this distance was later extended to the 100-kilometre scale5,6 with decoy-state QKD and more recently to the 500-kilometre scale7-10 with measurement-device-independent QKD. Several small-scale QKD networks have also been tested outside the laboratory11-14. However, a global QKD network requires a practically (not just theoretically) secure and reliable QKD network that can be used by a large number of users distributed over a wide area15. Quantum repeaters16,17 could in principle provide a viable option for such a global network, but they cannot be deployed using current technology18. Here we demonstrate an integrated space-to-ground quantum communication network that combines a large-scale fibre network of more than 700 fibre QKD links and two high-speed satellite-to-ground free-space QKD links. Using a trusted relay structure, the fibre network on the ground covers more than 2,000 kilometres, provides practical security against the imperfections of realistic devices, and maintains long-term reliability and stability. The satellite-to-ground QKD achieves an average secret-key rate of 47.8 kilobits per second for a typical satellite pass-more than 40 times higher than achieved previously. Moreover, its channel loss is comparable to that between a geostationary satellite and the ground, making the construction of more versatile and ultralong quantum links via geosynchronous satellites feasible. Finally, by integrating the fibre and free-space QKD links, the QKD network is extended to a remote node more than 2,600 kilometres away, enabling any user in the network to communicate with any other, up to a total distance of 4,600 kilometres.

3.
Nat Methods ; 20(2): 276-283, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36646897

RESUMO

Cryo-electron tomography (cryo-ET) has become a powerful approach to study the high-resolution structure of cellular macromolecular machines in situ. However, the current correlative cryo-fluorescence and electron microscopy lacks sufficient accuracy and efficiency to precisely prepare cryo-lamellae of target locations for subsequent cryo-ET. Here we describe a precise cryogenic fabrication system, ELI-TriScope, which sets electron (E), light (L) and ion (I) beams at the same focal point to achieve accurate and efficient preparation of a target cryo-lamella. ELI-TriScope uses a commercial dual-beam scanning electron microscope modified to incorporate a cryo-holder-based transfer system and embed an optical imaging system just underneath the vitrified specimen. Cryo-focused ion beam milling can be accurately navigated by monitoring the real-time fluorescence signal of the target molecule. Using ELI-TriScope, we prepared a batch of cryo-lamellae of HeLa cells targeting the centrosome with a success rate of ~91% and discovered new in situ structural features of the human centrosome by cryo-ET.


Assuntos
Tomografia com Microscopia Eletrônica , Elétrons , Humanos , Tomografia com Microscopia Eletrônica/métodos , Microscopia Crioeletrônica/métodos , Células HeLa , Substâncias Macromoleculares
4.
J Immunol ; 212(8): 1287-1306, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38426910

RESUMO

Myocarditis has emerged as an immune-related adverse event of immune checkpoint inhibitor (ICI) cancer therapy associated with significant mortality. To ensure patients continue to safely benefit from life-saving cancer therapy, an understanding of fundamental immunological phenomena underlying ICI myocarditis is essential. We recently developed the NOD-cMHCI/II-/-.DQ8 mouse model that spontaneously develops myocarditis with lower mortality than observed in previous HLA-DQ8 NOD mouse strains. Our strain was rendered murine MHC class I and II deficient using CRISPR/Cas9 technology, making it a genetically clean platform for dissecting CD4+ T cell-mediated myocarditis in the absence of classically selected CD8+ T cells. These mice are highly susceptible to myocarditis and acute heart failure following anti-PD-1 ICI-induced treatment. Additionally, anti-PD-1 administration accelerates skeletal muscle myositis. Using histology, flow cytometry, adoptive transfers, and RNA sequencing analyses, we performed a thorough characterization of cardiac and skeletal muscle T cells, identifying shared and unique characteristics of both populations. Taken together, this report details a mouse model with features of a rare, but highly lethal clinical presentation of overlapping myocarditis and myositis following ICI therapy. This study sheds light on underlying immunological mechanisms in ICI myocarditis and provides the basis for further detailed analyses of diagnostic and therapeutic strategies.


Assuntos
Diabetes Mellitus Experimental , Antígenos HLA-DQ , Miocardite , Miosite , Neoplasias , Humanos , Camundongos , Animais , Camundongos Endogâmicos NOD , Inibidores de Checkpoint Imunológico/uso terapêutico , Miosite/induzido quimicamente , Miosite/patologia
5.
Nature ; 582(7813): 501-505, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32541968

RESUMO

Quantum key distribution (QKD)1-3 is a theoretically secure way of sharing secret keys between remote users. It has been demonstrated in a laboratory over a coiled optical fibre up to 404 kilometres long4-7. In the field, point-to-point QKD has been achieved from a satellite to a ground station up to 1,200 kilometres away8-10. However, real-world QKD-based cryptography targets physically separated users on the Earth, for which the maximum distance has been about 100 kilometres11,12. The use of trusted relays can extend these distances from across a typical metropolitan area13-16 to intercity17 and even intercontinental distances18. However, relays pose security risks, which can be avoided by using entanglement-based QKD, which has inherent source-independent security19,20. Long-distance entanglement distribution can be realized using quantum repeaters21, but the related technology is still immature for practical implementations22. The obvious alternative for extending the range of quantum communication without compromising its security is satellite-based QKD, but so far satellite-based entanglement distribution has not been efficient23 enough to support QKD. Here we demonstrate entanglement-based QKD between two ground stations separated by 1,120 kilometres at a finite secret-key rate of 0.12 bits per second, without the need for trusted relays. Entangled photon pairs were distributed via two bidirectional downlinks from the Micius satellite to two ground observatories in Delingha and Nanshan in China. The development of a high-efficiency telescope and follow-up optics crucially improved the link efficiency. The generated keys are secure for realistic devices, because our ground receivers were carefully designed to guarantee fair sampling and immunity to all known side channels24,25. Our method not only increases the secure distance on the ground tenfold but also increases the practical security of QKD to an unprecedented level.

6.
Exp Cell Res ; 436(1): 113956, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38341081

RESUMO

Patients with hepatocellular carcinoma (HCC) are vulnerable to drug resistance. Although drug resistance has been taken much attention to HCC therapy, little is known of regorafenib and regorafenib resistance (RR). This study aimed to determine the drug resistance pattern and the role of RhoA in RR. Two regorafenib-resistant cell lines were constructed based on Huh7 and Hep3B cell lines. In vitro and in vivo assays were conducted to study RhoA expression, the activity of Hippo signaling pathway and cancer stem cell (CSC) traits. The data showed that RhoA was highly expressed, Hippo signaling was hypoactivated and CSC traits were more prominent in RR cells. Inhibiting RhoA could reverse RR, and the alliance of RhoA inhibition and regorafenib synergistically attenuated CSC phenotype. Furthermore, inhibiting LARG/RhoA increased Kibra/NF2 complex formation, prevented YAP from shuttling into the nucleus and repressed CD44 mRNA expression. Clinically, the high expression of RhoA correlated with poor prognosis. LARG, RhoA, YAP1 and CD44 show positive correlation with each other. Thus, inhibition of RhoGEF/RhoA has the potential to reverse RR and repress CSC phenotype in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Piridinas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Via de Sinalização Hippo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Compostos de Fenilureia/farmacologia
7.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38300178

RESUMO

Obesity has been linked to abnormal frontal function, including the white matter fibers of anterior portion of the corpus callosum, which is crucial for information exchange within frontal cortex. However, alterations in white matter anatomical connectivity between corpus callosum and cortical regions in patients with obesity have not yet been investigated. Thus, we enrolled 72 obese and 60 age-/gender-matched normal weight participants who underwent clinical measurements and diffusion tensor imaging. Probabilistic tractography with connectivity-based classification was performed to segment the corpus callosum and quantify white matter anatomical connectivity between subregions of corpus callosum and cortical regions, and associations between corpus callosum-cortex white matter anatomical connectivity and clinical behaviors were also assessed. Relative to normal weight individuals, individuals with obesity exhibited significantly greater white matter anatomical connectivity of corpus callosum-orbitofrontal cortex, which was positively correlated with body mass index and self-reported disinhibition of eating behavior, and lower white matter anatomical connectivity of corpus callosum-prefrontal cortex, which was significantly negatively correlated with craving for high-calorie food cues. The findings show that alterations in white matter anatomical connectivity between corpus callosum and frontal regions involved in reward and executive control are associated with abnormal eating behaviors.


Assuntos
Corpo Caloso , Substância Branca , Humanos , Corpo Caloso/diagnóstico por imagem , Encéfalo , Imagem de Tensor de Difusão/métodos , Substância Branca/diagnóstico por imagem , Obesidade/diagnóstico por imagem
8.
Nano Lett ; 24(34): 10614-10623, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39046153

RESUMO

Because of the challenges posed by anatomical uncertainties and the low resolution of plain computed tomography (CT) scans, implementing adaptive radiotherapy (ART) for small hepatocellular carcinoma (sHCC) using artificial intelligence (AI) faces obstacles in tumor identification-alignment and automatic segmentation. The current study aims to improve sHCC imaging for ART using a gold nanoparticle (Au NP)-based CT contrast agent to enhance AI-driven automated image processing. The synthesized charged Au NPs demonstrated notable in vitro aggregation, low cytotoxicity, and minimal organ toxicity. Over time, an in situ sHCC mouse model was established for in vivo CT imaging at multiple time points. The enhanced CT images processed using 3D U-Net and 3D Trans U-Net AI models demonstrated high geometric and dosimetric accuracy. Therefore, charged Au NPs enable accurate and automatic sHCC segmentation in CT images using classical AI models, potentially addressing the technical challenges related to tumor identification, alignment, and automatic segmentation in CT-guided online ART.


Assuntos
Carcinoma Hepatocelular , Ouro , Neoplasias Hepáticas , Nanopartículas Metálicas , Radioterapia Guiada por Imagem , Tomografia Computadorizada por Raios X , Ouro/química , Carcinoma Hepatocelular/radioterapia , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Animais , Tomografia Computadorizada por Raios X/métodos , Nanopartículas Metálicas/química , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Camundongos , Radioterapia Guiada por Imagem/métodos , Humanos , Meios de Contraste/química , Inteligência Artificial , Linhagem Celular Tumoral
9.
Gastroenterology ; 165(2): 402-413.e13, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36894035

RESUMO

BACKGROUND & AIMS: Diagnosing gastric cancer (GC) while the disease remains eligible for surgical resection is challenging. In view of this clinical challenge, novel and robust biomarkers for early detection thus improving prognosis of GC are necessary. The present study is to develop a blood-based long noncoding RNA (LR) signature for the early-detection of GC. METHODS: The present 3-step study incorporated data from 2141 patients, including 888 with GC, 158 with chronic atrophic gastritis, 193 with intestinal metaplasia, 501 healthy donors, and 401 with other gastrointestinal cancers. The LR profile of stage I GC tissue samples were analyzed using transcriptomic profiling in discovery phase. The extracellular vesicle (EV)-derived LR signature was identified with a training cohort (n = 554) and validated with 2 external cohorts (n = 429 and n = 504) and a supplemental cohort (n = 69). RESULTS: In discovery phase, one LR (GClnc1) was found to be up-regulated in both tissue and circulating EV samples with an area under the curve (AUC) of 0.9369 (95% confidence interval [CI], 0.9073-0.9664) for early-stage GC (stage I/II). The diagnostic performance of this biomarker was further confirmed in 2 external validation cohorts (Xi'an cohort, AUC: 0.8839; 95% CI: 0.8336-0.9342; Beijing cohort, AUC: 0.9018; 95% CI: 0.8597-0.9439). Moreover, EV-derived GClnc1 robustly distinguished early-stage GC from precancerous lesions (chronic atrophic gastritis and intestinal metaplasia) and GC with negative traditional gastrointestinal biomarkers (CEA, CA72-4, and CA19-9). The low levels of this biomarker in postsurgery and other gastrointestinal tumor plasma samples indicated its GC specificity. CONCLUSIONS: EV-derived GClnc1 serves as a circulating biomarker for the early detection of GC, thus providing opportunities for curative surgery and improved survival outcomes.


Assuntos
Gastrite Atrófica , Neoplasias Gástricas , Humanos , Biomarcadores Tumorais/genética , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/cirurgia , Gastrite Atrófica/diagnóstico , Gastrite Atrófica/genética , Antígeno CA-19-9 , Detecção Precoce de Câncer , Metaplasia
10.
Small ; 20(43): e2400770, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38934533

RESUMO

Increased expression of immune check point genes, such as PD-L1, is one of the main reasons for immunosuppression, especially for colon cancer. Development of novel therapeutic strategies is of great importance to improve the prognosis. In this study, outer membrane vesicles (OMV) derived from Gram-negative bacteria are engineered to immune checkpoint blockade nanosystem for efficient elicitation of anti-tumor immunity. Briefly, the OMVs are engineered with Lyp1-Traptavidin (S52G, R53D mutant of streptavidin) fusion protein displayed on the surface. The Lyp-1 endows the OMV with the capacity to target tumor tissues, while the Traptavidin ensures easy decoration of biotinylated anti-PD-L1 and biotinylated M6P (mannose 6-phosphate). The simultaneously anchored anti-PD-L1 and M6P (ligand for cation-independent mannose 6-phosphate receptor) on the engineered OMVs coordinately direct the membrane PD-L1 to lysosome for degradation, and thus unleash the anti-tumor immunity. With syngeneic tumor model, the engineered OMVs are confirmed to boost immunity, inhibit cancer growth, and thus prolong survival. Together, A proposed OMV-based modular nanosystem that enables assembly of biotinylated anti-PD-L1 and M6P on the surface for tumor-targeted immune checkpoint blockade.


Assuntos
Antígeno B7-H1 , Membrana Externa Bacteriana , Lisossomos , Antígeno B7-H1/metabolismo , Animais , Lisossomos/metabolismo , Membrana Externa Bacteriana/metabolismo , Camundongos , Humanos , Linhagem Celular Tumoral
11.
Nat Mater ; 22(10): 1182-1188, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37592031

RESUMO

Since the first discovery of the fatigue phenomenon in the late 1830s, efforts to fight against fatigue failure have continued. Here we report a fatigue resistance phenomenon in nano-TiB2-decorated AlSi10Mg enabled by additive manufacturing. This fatigue resistance mechanism benefits from the three-dimensional dual-phase cellular nanostructure, which acts as a strong volumetric nanocage to prevent localized damage accumulation, thus inhibiting fatigue crack initiation. The intrinsic fatigue strength limit of nano-TiB2-decorated AlSi10Mg was proven to be close to its tensile strength through the in situ fatigue tests of a defect-free microsample. To demonstrate the practical applicability of this mechanism, printed bulk nano-TiB2-decorated AlSi10Mg achieved fatigue resistance more than double those of other additive manufacturing Al alloys and surpassed those of high-strength wrought Al alloys. This strategy of additive-manufacturing-assisted nanostructure engineering can be extended to the development of other dual-phase fatigue-resistant metals.

12.
Opt Express ; 32(12): 20931-20947, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859461

RESUMO

In recent decades, rapid advances in astronomical imaging campaigns have generated an urgent need for detailed spectroscopic surveys with increased speed and efficiency. The 6.5 m MUltiplexed Survey Telescope (MUST) aims to address these current demands. The performance of the multi-object fiber-fed spectrograph (MOFS) plays a critical role for spectroscopic survey telescopes, directly influencing the realization of scientific aims. In this paper, we demonstrate a high-resolution and highly-multiplexed option for MOFS of MUST. The system is believed to be first to apply a 92 mm × 92 mm large-size detector in a Schmidt-like camera and reduces the average central obscuration to 14%. Thanks to the F/1.25 camera design with excellent image quality, the spectrograph achieves up to 800 150µm-large-core optical fibers integration. It can obtain the broadband spectral information (395 nm-435 nm, 520 nm-570 nm, 610 nm-680 nm) of 800 objects with a high resolution of >16,000 within one exposure. The spectrograph theory, design method, and final system scheme of the MOFS can offer good reference and guidance for the spectrograph design in the spectroscopic survey.

13.
Phys Rev Lett ; 133(2): 020201, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39073932

RESUMO

The emergence of quantum mechanics and general relativity has transformed our understanding of the natural world significantly. However, integrating these two theories presents immense challenges, and their interplay remains untested. Recent theoretical studies suggest that the single-photon interference covering huge space can effectively probe the interface between quantum mechanics and general relativity. We developed an alternative design using unbalanced Michelson interferometers to address this and validated its feasibility over an 8.4 km free-space channel. Using a high-brightness single-photon source based on quantum dots, we demonstrated single-photon interference along this long-distance baseline. We achieved a phase measurement precision of 16.2 mrad, which satisfied the measurement requirements for a gravitational redshift at the geosynchronous orbit by 5 times the standard deviation. Our results confirm the feasibility of the single-photon version of the Colella-Overhauser-Werner experiment for testing the quantum effects in curved spacetime.

14.
Cell Biol Toxicol ; 40(1): 19, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573528

RESUMO

RNA-binding proteins (RBPs) make vital impacts on tumor progression and are important potential targets for tumor treatment. Previous studies have shown that RBP regulator of differentiation 1 (ROD1), enriched in the nucleus, is abnormally expressed and functions as a splicing factor in tumors; however, the mechanism underlying its involvement in gastric cancer (GC) is unknown. In this study, ROD1 is found to stimulate GC cell proliferation and metastasis and is related to poor patient prognosis. In vitro experiments showed that ROD1 influences GC proliferation and metastasis through modulating the imbalance of the level of the oncogenic gene OIP5 and the tumor suppressor gene GPD1L. Further studies showed that the N6-methyladenosine (m6A) "reader" protein YTHDC1 can interact with ROD1 and regulate the balance of the expression of the downstream molecules OIP5/GPD1L by promoting the nuclear enrichment of ROD1. Therefore, YTHDC1 stimulates GC development and progression through modulating nuclear enrichment of the splicing factor ROD1.


Assuntos
Neoplasias Gástricas , Humanos , Diferenciação Celular , Proteínas do Tecido Nervoso , Fatores de Processamento de RNA
15.
Acta Pharmacol Sin ; 45(2): 391-404, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37803139

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common and deadly cancers in the world. The therapeutic outlook for HCC patients has significantly improved with the advent and development of systematic and targeted therapies such as sorafenib and lenvatinib; however, the rise of drug resistance and the high mortality rate necessitate the continuous discovery of effective targeting agents. To discover novel anti-HCC compounds, we first constructed a deep learning-based chemical representation model to screen more than 6 million compounds in the ZINC15 drug-like library. We successfully identified LGOd1 as a novel anticancer agent with a characteristic levoglucosenone (LGO) scaffold. The mechanistic studies revealed that LGOd1 treatment leads to HCC cell death by interfering with cellular copper homeostasis, which is similar to a recently reported copper-dependent cell death named cuproptosis. While the prototypical cuproptosis is brought on by copper ionophore-induced copper overload, mechanistic studies indicated that LGOd1 does not act as a copper ionophore, but most likely by interacting with the copper chaperone protein CCS, thus LGOd1 represents a potentially new class of compounds with unique cuproptosis-inducing property. In summary, our findings highlight the critical role of bioavailable copper in the regulation of cell death and represent a novel route of cuproptosis induction.


Assuntos
Carcinoma Hepatocelular , Aprendizado Profundo , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Cobre , Neoplasias Hepáticas/tratamento farmacológico , Ionóforos , Apoptose
16.
Cereb Cortex ; 33(5): 2037-2047, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-35580853

RESUMO

Habenular (Hb) processes negative emotions that may drive compulsive food-intake. Its functional changes were reported following laparoscopic-sleeve-gastrectomy (LSG). However, structural connectivity (SC) of Hb-homeostatic/hedonic circuits after LSG remains unclear. We selected regions implicated in homeostatic/hedonic regulation that have anatomical connections with Hb as regions-of-interest (ROIs), and used diffusion-tensor-imaging with probabilistic tractography to calculate SC between Hb and these ROIs in 30 obese participants before LSG (PreLSG) and at 12-month post-LSG (PostLSG12) and 30 normal-weight controls. Three-factor-eating-questionnaire (TFEQ) and Dutch-eating-behavior-questionnaire (DEBQ) were used to assess eating behaviors. LSG significantly decreased weight, negative emotion, and improved self-reported eating behavior. LSG increased SC between the Hb and homeostatic/hedonic regions including hypothalamus (Hy), bilateral superior frontal gyri (SFG), left amygdala (AMY), and orbitofrontal cortex (OFC). TFEQ-hunger negatively correlated with SC of Hb-Hy at PostLSG12; and increased SC of Hb-Hy correlated with reduced depression and DEBQ-external eating. TFEQ-disinhibition negatively correlated with SC of Hb-bilateral SFG at PreLSG. Increased SC of Hb-left AMY correlated with reduced DEBQ-emotional eating. Higher percentage of total weight-loss negatively correlated with SC of Hb-left OFC at PreLSG. Enhanced SC of Hb-homeostatic/hedonic regulatory regions post-LSG may contribute to its beneficial effects in improving eating behaviors including negative emotional eating, and long-term weight-loss.


Assuntos
Laparoscopia , Obesidade Mórbida , Humanos , Comportamento Alimentar/fisiologia , Obesidade Mórbida/psicologia , Obesidade Mórbida/cirurgia , Emoções , Gastrectomia , Redução de Peso/fisiologia , Resultado do Tratamento
17.
Cochrane Database Syst Rev ; 2: CD015014, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38421211

RESUMO

BACKGROUND: Choosing an optimal reconstruction method is pivotal for patients with gastric cancer undergoing distal gastrectomy. The uncut Roux-en-Y reconstruction, a variant of the conventional Roux-en-Y approach (or variant of the Billroth II reconstruction), employs uncut devices to occlude the afferent loop of the jejunum. This modification is designed to mitigate postgastrectomy syndrome and enhance long-term functional outcomes. However, the comparative benefits and potential harms of this approach compared to other reconstruction techniques remain a topic of debate. OBJECTIVES: To assess the benefits and harms of uncut Roux-en-Y reconstruction after distal gastrectomy in patients with gastric cancer. SEARCH METHODS: We searched CENTRAL, PubMed, Embase, WanFang Data, China National Knowledge Infrastructure, and clinical trial registries for published and unpublished trials up to November 2023. We also manually reviewed references from relevant systematic reviews identified by our search. We did not impose any language restrictions. SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs comparing uncut Roux-en-Y reconstruction versus other reconstructions after distal gastrectomy for gastric cancer. The comparison groups encompassed other reconstructions such as Billroth I, Billroth II (with or without Braun anastomosis), and Roux-en-Y reconstruction. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures. The critical outcomes included health-related quality of life at least six months after surgery, major postoperative complications within 30 days after surgery according to the Clavien-Dindo Classification (grades III to V), anastomotic leakage within 30 days, changes in body weight (kg) at least six months after surgery, and incidence of bile reflux, remnant gastritis, and oesophagitis at least six months after surgery. We used the GRADE approach to evaluate the certainty of the evidence. MAIN RESULTS: We identified eight trials, including 1167 participants, which contributed data to our meta-analyses. These trials were exclusively conducted in East Asian countries, predominantly in China. The studies varied in the types of uncut devices used, ranging from 2- to 6-row linear staplers to suture lines. The follow-up periods for long-term outcomes spanned from 3 months to 42 months, with most studies focusing on a 6- to 12-month range. We rated the certainty of evidence from low to very low. Uncut Roux-en-Y reconstruction versus Billroth II reconstruction In the realm of surgical complications, very low-certainty evidence suggests that uncut Roux-en-Y reconstruction compared with Billroth II reconstruction may make little to no difference to major postoperative complications (risk ratio (RR) 0.98, 95% confidence interval (CI) 0.24 to 4.05; I² = 0%; risk difference (RD) 0.00, 95% CI -0.04 to 0.04; I² = 0%; 2 studies, 282 participants; very low-certainty evidence) and incidence of anastomotic leakage (RR 0.64, 95% CI 0.29 to 1.44; I² not applicable; RD -0.00, 95% CI -0.03 to 0.02; I² = 32%; 3 studies, 615 participants; very low-certainty evidence). We are very uncertain about these results. Focusing on long-term outcomes, low- to very low-certainty evidence suggests that uncut Roux-en-Y reconstruction compared with Billroth II reconstruction may make little to no difference to changes in body weight (mean difference (MD) 0.04 kg, 95% CI -0.84 to 0.92 kg; I² = 0%; 2 studies, 233 participants; low-certainty evidence), may reduce the incidence of bile reflux into the remnant stomach (RR 0.67, 95% CI 0.55 to 0.83; RD -0.29, 95% CI -0.43 to -0.16; number needed to treat for an additional beneficial outcome (NNTB) 4, 95% CI 3 to 7; 1 study, 141 participants; low-certainty evidence), and may have little or no effect on the incidence of remnant gastritis (RR 0.27, 95% CI 0.01 to 5.06; I2 = 78%; RD -0.15, 95% CI -0.23 to -0.07; I2 = 0%; NNTB 7, 95% CI 5 to 15; 2 studies, 265 participants; very low-certainty evidence). No studies reported on quality of life or the incidence of oesophagitis. Uncut Roux-en-Y reconstruction versus Roux-en-Y reconstruction In the realm of surgical complications, very low-certainty evidence suggests that uncut Roux-en-Y reconstruction compared with Roux-en-Y reconstruction may make little to no difference to major postoperative complications (RR 4.74, 95% CI 0.23 to 97.08; I² not applicable; RD 0.01, 95% CI -0.02 to 0.04; I² = 0%; 2 studies, 256 participants; very low-certainty evidence) and incidence of anastomotic leakage (RR 0.34, 95% CI 0.05 to 2.08; I² = 0%; RD -0.02, 95% CI -0.06 to 0.02; I² = 0%; 2 studies, 213 participants; very low-certainty evidence). We are very uncertain about these results. Focusing on long-term outcomes, very low-certainty evidence suggests that uncut Roux-en-Y reconstruction compared with Roux-en-Y reconstruction may increase the incidence of bile reflux into the remnant stomach (RR 10.74, 95% CI 3.52 to 32.76; RD 0.57, 95% CI 0.43 to 0.71; NNT for an additional harmful outcome (NNTH) 2, 95% CI 2 to 3; 1 study, 108 participants; very low-certainty evidence) and may make little to no difference to the incidence of remnant gastritis (RR 1.18, 95% CI 0.69 to 2.01; I² = 60%; RD 0.03, 95% CI -0.03 to 0.08; I² = 0%; 3 studies, 361 participants; very low-certainty evidence) and incidence of oesophagitis (RR 0.82, 95% CI 0.53 to 1.26; I² = 0%; RD -0.02, 95% CI -0.07 to 0.03; I² = 0%; 3 studies, 361 participants; very low-certainty evidence). We are very uncertain about these results. Data were insufficient to assess the impact on quality of life and changes in body weight. AUTHORS' CONCLUSIONS: Given the predominance of low- to very low-certainty evidence, this Cochrane review faces challenges in providing definitive clinical guidance. We found the majority of critical outcomes may be comparable between the uncut Roux-en-Y reconstruction and other methods, but we are very uncertain about most of these results. Nevertheless, it indicates that uncut Roux-en-Y reconstruction may reduce the incidence of bile reflux compared to Billroth-II reconstruction, albeit with low certainty. In contrast, compared to Roux-en-Y reconstruction, uncut Roux-en-Y may increase bile reflux incidence, based on very low-certainty evidence. To strengthen the evidence base, further rigorous and long-term trials are needed. Additionally, these studies should explore variations in surgical procedures, particularly regarding uncut devices and methods to prevent recanalisation. Future research may potentially alter the conclusions of this review.


Assuntos
Anastomose em-Y de Roux , Gastrectomia , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Gastrectomia/métodos , Gastrectomia/efeitos adversos , Anastomose em-Y de Roux/métodos , Anastomose em-Y de Roux/efeitos adversos , Qualidade de Vida , Gastroenterostomia/métodos , Complicações Pós-Operatórias , Jejuno/cirurgia , Síndromes Pós-Gastrectomia/prevenção & controle , Viés
18.
J Nanobiotechnology ; 22(1): 305, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822364

RESUMO

BACKGROUND: Renal fibrosis is a progressive process associated with chronic kidney disease (CKD), contributing to impaired kidney function. Active constituents in traditional Chinese herbs, such as emodin (EMO) and asiatic acid (AA), exhibit potent anti-fibrotic properties. However, the oral administration of EMO and AA results in low bioavailability and limited kidney accumulation. Additionally, while oral probiotics have been accepted for CKD treatment through gut microbiota modulation, a significant challenge lies in ensuring their viability upon administration. Therefore, our study aims to address both renal fibrosis and gut microbiota imbalance through innovative co-delivery strategies. RESULTS: In this study, we developed yeast cell wall particles (YCWPs) encapsulating EMO and AA self-assembled nanoparticles (NPYs) and embedded them, along with Lactobacillus casei Zhang, in chitosan/sodium alginate (CS/SA) microgels. The developed microgels showed significant controlled release properties for the loaded NPYs and prolonged the retention time of Lactobacillus casei Zhang (L. casei Zhang) in the intestine. Furthermore, in vivo biodistribution showed that the microgel-carried NPYs significantly accumulated in the obstructed kidneys of rats, thereby substantially increasing the accumulation of EMO and AA in the impaired kidneys. More importantly, through hitchhiking delivery based on yeast cell wall and positive modulation of gut microbiota, our microgels with this synergistic strategy of therapeutic and modulatory interactions could regulate the TGF-ß/Smad signaling pathway and thus effectively ameliorate renal fibrosis in unilateral ureteral obstruction (UUO) rats. CONCLUSION: In conclusion, our work provides a new strategy for the treatment of renal fibrosis based on hitchhiking co-delivery of nanodrugs and probiotics to achieve synergistic effects of disease treatment and targeted gut flora modulation.


Assuntos
Fibrose , Microbioma Gastrointestinal , Rim , Nanopartículas , Ratos Sprague-Dawley , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Ratos , Administração Oral , Masculino , Rim/patologia , Rim/efeitos dos fármacos , Nanopartículas/química , Microgéis/química , Lacticaseibacillus casei , Probióticos/farmacologia , Insuficiência Renal Crônica/tratamento farmacológico , Quitosana/química , Alginatos/química , Triterpenos Pentacíclicos/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Distribuição Tecidual , Parede Celular
19.
J Nanobiotechnology ; 22(1): 24, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191388

RESUMO

The iron oxide nanoparticles (IONPs), possessing both magnetic behavior and semiconductor property, have been extensively used in multifunctional biomedical fields due to their biocompatible, biodegradable and low toxicity, such as anticancer, antibacterial, cell labelling activities. Nevertheless, there are few IONPs in clinical use at present. Some IONPs approved for clinical use have been withdrawn due to insufficient understanding of its biomedical applications. Therefore, a systematic summary of IONPs' preparation and biomedical applications is crucial for the next step of entering clinical practice from experimental stage. This review summarized the existing research in the past decade on the biological interaction of IONPs with animal/cells models, and their clinical applications in human. This review aims to provide cutting-edge knowledge involved with IONPs' biological effects in vivo and in vitro, and improve their smarter design and application in biomedical research and clinic trials.


Assuntos
Antibacterianos , Nanopartículas Magnéticas de Óxido de Ferro , Animais , Humanos
20.
BMC Anesthesiol ; 24(1): 110, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519945

RESUMO

OBJECTIVE: The current study used a composite outcome to investigate whether applying the ERAS protocol would enhance the recovery of patients undergoing laparoscopic total gastrectomy (LTG). EXPOSURES: Laparoscopic total gastrectomy and perioperative interventions were the exposure. An ERAS clinical pathway consisting of 14 items was implemented and assessed. Patients were divided into either ERAS-compliant or non-ERAS-compliant group according the adherence above 9/14 or not. MAIN OUTCOMES AND MEASURES: The primary study outcome was a composite outcome called 'optimal postoperative recovery' with the definition as below: discharge within 6 days with no sever complications and no unplanned re-operation or readmission within 30 days postoperatively. Univariate logistic regression analysis and multivariate logistic regression analysis were used to model optimal postoperative recovery and compliance, adjusting for patient-related and disease-related characteristics. RESULTS: A total of 252 patients were included in this retrospective study, 129 in the ERAS compliant group and 123 in the non-ERAS-compliant group. Of these, 79.07% of the patients in ERAS compliant group achieved optimal postoperative recovery, whereas 61.79% of patients in non-ERAS-compliant group did (P = 0.0026). The incidence of sever complications was lower in the ERAS-compliant group (1.55% vs. 6.5%, P = 0.0441). No patients in ERAS compliant group had unplanned re-operation, whereas 5.69% (7/123) of patients in non-ERAS-compliant group had (p = 0.006). The median length of the postoperative hospital stay was shorter in the in the ERAS compliant group (5.51 vs. 5.68 days, P = 0.01). Both logistic (OR 2.01, 95% CI 1.21-3.34) and stepwise regression (OR 2.07, 95% CI 1.25-3.41) analysis showed that high overall compliance with the ERAS protocol facilitated optimal recovery in such patients. In bivariate analysis of compliance for patients who had an optimal postoperative recovery, carbohydrate drinks (p = 0.0196), early oral feeding (P = 0.0043), early mobilization (P = 0.0340), and restrictive intravenous fluid administration (P < 0.0001) were significantly associated with optimal postoperative recovery. CONCLUSIONS AND RELEVANCE: Patients with higher ERAS compliance (almost 70% of the accomplishment) suffered less severe postoperative complications and were more likely to achieve optimal postoperative recovery.


Assuntos
Recuperação Pós-Cirúrgica Melhorada , Laparoscopia , Humanos , Laparoscopia/métodos , Estudos Retrospectivos , Gastrectomia/métodos , Tempo de Internação , Complicações Pós-Operatórias/epidemiologia
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