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1.
Int J Mol Sci ; 25(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38791286

RESUMO

In clinical practice, tissue adhesives have emerged as an alternative tool for wound treatments due to their advantages in ease of use, rapid application, less pain, and minimal tissue damage. Since most tissue adhesives are designed for internal use or wound treatments, the biodegradation of adhesives is important. To endow tissue adhesives with biodegradability, in the past few decades, various biodegradable polymers, either natural polymers (such as chitosan, hyaluronic acid, gelatin, chondroitin sulfate, starch, sodium alginate, glucans, pectin, functional proteins, and peptides) or synthetic polymers (such as poly(lactic acid), polyurethanes, polycaprolactone, and poly(lactic-co-glycolic acid)), have been utilized to develop novel biodegradable tissue adhesives. Incorporated biodegradable polymers are degraded in vivo with time under specific conditions, leading to the destruction of the structure and the further degradation of tissue adhesives. In this review, we first summarize the strategies of utilizing biodegradable polymers to develop tissue adhesives. Furthermore, we provide a symmetric overview of the biodegradable polymers used for tissue adhesives, with a specific focus on the degradability and applications of these tissue adhesives. Additionally, the challenges and perspectives of biodegradable polymer-based tissue adhesives are discussed. We expect that this review can provide new inspirations for the design of novel biodegradable tissue adhesives for biomedical applications.


Assuntos
Materiais Biocompatíveis , Adesivos Teciduais , Adesivos Teciduais/química , Humanos , Animais , Materiais Biocompatíveis/química , Polímeros/química , Plásticos Biodegradáveis/química , Quitosana/química
2.
ACS Sens ; 9(4): 2122-2133, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38602840

RESUMO

Terahertz (THz) spectroscopy has impressive capability for label-free biosensing, but its utility in clinical laboratories is rarely reported due to often unsatisfactory detection performances. Here, we fabricated metal-graphene hybrid THz metasurfaces (MSs) for the sensitive and enzyme-free detection of circulating tumor DNA (ctDNA) in pancreatic cancer plasma samples. The feasibility and mechanism of the enhanced effects of a graphene bridge across the MS and amplified by gold nanoparticles (AuNPs) were investigated experimentally and theoretically. The AuNPs serve to boost charge injection in the graphene film and result in producing a remarkable change in the graded transmissivity index to THz radiation of the MS resonators. Assay design utilizes this feature and a cascade hybridization chain reaction initiated on magnetic beads in the presence of target ctDNA to achieve dual signal amplification (chemical and optical). In addition to demonstrating subfemtomolar detection sensitivity and single-nucleotide mismatch selectivity, the proposed method showed remarkable capability to discriminate between pancreatic cancer patients and healthy individuals by recognizing and quantifying targeted ctDNAs. The introduction of graphene to the metasurface produces an improved sensitivity of 2 orders of magnitude for ctDNA detection. This is the first study to report the combined application of graphene and AuNPs in biosensing by THz spectroscopic resonators and provides a combined identification scheme to detect and discriminate different biological analytes, including nucleic acids, proteins, and various biomarkers.


Assuntos
DNA Tumoral Circulante , Ouro , Grafite , Nanopartículas Metálicas , Neoplasias Pancreáticas , Grafite/química , Humanos , Ouro/química , Nanopartículas Metálicas/química , DNA Tumoral Circulante/sangue , DNA Tumoral Circulante/genética , DNA Tumoral Circulante/análise , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/diagnóstico , Técnicas Biossensoriais/métodos , Espectroscopia Terahertz/métodos , Hibridização de Ácido Nucleico , Limite de Detecção
3.
Org Lett ; 26(16): 3435-3440, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38629704

RESUMO

We have developed a widely applicable (radio)fluoro-iodination of alkenes using readily available and easily handled KF (18F). The reactions exhibited high functional group tolerance and needed only an ambient atmosphere. Furthermore, the resulting product could be further functionalized with various nucleophiles.

4.
Ren Fail ; 46(1): 2338929, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38632963

RESUMO

OBJECTIVE: To delineate the efficacy and safety profile of hemodiafiltration with endogenous reinfusion (HFR) for uremic toxin removal in patients undergoing maintenance hemodialysis (MHD). METHODS: Patients who have been on MHD for a period of at least 3 months were enrolled. Each subject underwent one HFR and one hemodiafiltration (HDF) treatment. Blood samples were collected before and after a single HFR or HDF treatment to test uremic toxin levels and to calculate clearance rate. The primary efficacy endpoint was to compare uremic toxin levels of indoxyl sulfate (IS), λ-free light chains (λFLC), and ß2-microglobulin (ß2-MG) before and after HFR treatment. Secondary efficacy endpoints was to compare the levels of urea, interleukin-6 (IL-6), P-cresol, chitinase-3-like protein 1 (YKL-40), leptin (LEP), hippuric acid (HPA), trimethylamine N-oxide (TMAO), asymmetric dimethylarginine (ADMA), tumor necrosis factor-α (TNF-α), fibroblast growth factor 23 (FGF23) before and after HFR treatment. The study also undertook a comparative analysis of uremic toxin clearance between a single HFR and HDF treatment. Meanwhile, the lever of serum albumin and branched-chain amino acids before and after a single HFR or HDF treatment were compared. In terms of safety, the study was meticulous in recording vital signs and the incidence of adverse events throughout its duration. RESULTS: The study enrolled 20 patients. After a single HFR treatment, levels of IS, λFLC, ß2-MG, IL-6, P-cresol, YKL-40, LEP, HPA, TMAO, ADMA, TNF-α, and FGF23 significantly decreased (p < 0.001 for all). The clearance rates of λFLC, ß2-MG, IL-6, LEP, and TNF-α were significantly higher in HFR compared to HDF (p values: 0.036, 0.042, 0.041, 0.019, and 0.036, respectively). Compared with pre-HFR and post-HFR treatment, levels of serum albumin, valine, and isoleucine showed no significant difference (p > 0.05), while post-HDF, levels of serum albumin significantly decreased (p = 0.000). CONCLUSION: HFR treatment effectively eliminates uremic toxins from the bloodstream of patients undergoing MHD, especially protein-bound toxins and large middle-molecule toxins. Additionally, it retains essential physiological compounds like albumin and branched-chain amino acids, underscoring its commendable safety profile.


Assuntos
Cresóis , Hemodiafiltração , Metilaminas , Humanos , Hemodiafiltração/efeitos adversos , Projetos Piloto , Toxinas Urêmicas , Proteína 1 Semelhante à Quitinase-3 , Interleucina-6 , Fator de Necrose Tumoral alfa , Diálise Renal , Aminoácidos de Cadeia Ramificada , Albumina Sérica
6.
World J Surg ; 48(5): 1242-1251, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38530128

RESUMO

BACKGROUND: Hepatolithiasis is a complex condition that poses challenges and difficulties in surgical treatment. Three-dimensional visualization technology combined with fluorescence imaging (3DVT-FI) enables accurate preoperative assessment and real-time intraoperative navigation. However, the perioperative outcomes of 3DVT-FI in hepatolithiasis have not been reported. We aim to evaluate the efficacy of 3DVT-FI in the treatment of hepatolithiasis. METHODS: A retrospective analysis was performed on 128 patients who underwent hepatectomy for hepatolithiasis at the Department of Hepatobiliary Surgery, Zhujiang Hospital, between January 2017 and December 2022. Among them, 50 patients underwent hepatectomy using 3DVT-FI (3DVT-FI group), while 78 patients underwent conventional hepatectomy without 3DVT-FI (CH group). The operative data, postoperative liver function indices, complication rates and stone residue were compared between the two groups. RESULTS: There were no significant differences in preoperative baseline data between the two groups (p > 0.05). Compared with the CH group, the 3DVT-FI group exhibited lower intraoperative blood loss (140.00 ± 112.12 vs. 225.99 ± 186.50 mL, p = 0.001), and a lower intraoperative transfusion rate (8.0% vs. 23.1%, p = 0.027). The overall incidence of postoperative complications did not differ significantly (22.0% vs. 35.9%, p = 0.096). The 3DVT-FI group was associated with a lower immediate residual stone rate (16.0% vs. 34.6%, p = 0.021). There were no perioperative deaths in the 3DVT-FI group, while one perioperative death occurred in the CH group. CONCLUSIONS: The 3DVT-FI may offer significant benefits in terms of surgical safety, reduced intraoperative bleeding and decreased stone residue during hepatectomy for hepatolithiasis.


Assuntos
Hepatectomia , Imageamento Tridimensional , Verde de Indocianina , Hepatopatias , Imagem Óptica , Humanos , Hepatectomia/métodos , Estudos Retrospectivos , Feminino , Masculino , Pessoa de Meia-Idade , Imagem Óptica/métodos , Hepatopatias/cirurgia , Hepatopatias/diagnóstico por imagem , Adulto , Resultado do Tratamento , Idoso , Cirurgia Assistida por Computador/métodos
7.
Int J Surg ; 110(3): 1663-1676, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241321

RESUMO

BACKGROUND: Three-dimensional reconstruction visualization technology (3D-RVT) is an important tool in the preoperative assessment of patients undergoing liver resection. However, it is not clear whether this technique can improve short-term and long-term outcomes in patients with hepatocellular carcinoma (HCC) compared with two-dimensional (2D) imaging. METHOD: A total of 3402 patients from five centers were consecutively enrolled from January 2016 to December 2020, and grouped based on the use of 3D-RVT or 2D imaging for preoperative assessment. Baseline characteristics were balanced using propensity score matching (PSM, 1:1) and stabilized inverse probability of treatment-weighting (IPTW) to reduce potential selection bias. The perioperative outcomes, long-term overall survival (OS), and recurrence-free survival (RFS) were compared between the two groups. Cox-regression analysis was used to identify the risk factors associated with RFS. RESULTS: A total of 1681 patients underwent 3D-RVT assessment before hepatectomy (3D group), while 1721 patients used 2D assessment (2D group). The PSM cohort included 892 patient pairs. In the IPTW cohort, there were 1608.3 patients in the 3D group and 1777.9 patients in the 2D group. In both cohorts, the 3D group had shorter operation times, lower morbidity and liver failure rates, as well as shorter postoperative hospital stays. The 3D group had more margins ≥10 mm and better RFS than the 2D group. The presence of tumors with a diameter ≥5 cm, intraoperative blood transfusion and multiple tumors were identified as independent risk factors for RFS, while 3D assessment and anatomical resection were independent protective factors. CONCLUSION: In this multicenter study, perioperative outcomes and RFS of HCC patients following 3D-RVT assessment were significantly different from those following 2D imaging assessment. Thus, 3D-RVT may be a feasible alternative assessment method before hepatectomy for these patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Pontuação de Propensão , Hepatectomia/métodos , Imageamento Tridimensional , Estudos Retrospectivos
8.
J Am Coll Surg ; 238(3): 321-330, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37991244

RESUMO

BACKGROUND: The internal anatomy of the liver is extremely complex. Laparoscopic anatomical segmentectomy requires reference to the position and alignment of intrahepatic vascular. However, the surface of the liver lacks anatomical landmarks and the liver segment boundaries cannot be identified with the naked eye. Augmented reality navigation (ARN) and indocyanine green fluorescence imaging (FI) are emerging navigation tools in liver resection. This study aimed to explore the efficacy and application value of laparoscopic anatomical segmentectomy guided by ARN combined with indocyanine green FI. STUDY DESIGN: Ninety-eight patients who were diagnosed with hepatocellular carcinoma and underwent laparoscopic anatomical segmentectomy from January 2018 to January 2022 were retrospectively analyzed. They were divided into the ARN-FI group (45 patients) and the non-ARN-FI group (53 patients) based on whether ARN combined with FI was applied during the operation. The differences in intraoperative and postoperative outcomes were compared. RESULTS: There was no significant difference in preoperative baseline data and postoperative complication rates between the 2 groups. Compared with the non-ARN-FI group, the ARN-FI group had much lower intraoperative blood loss (100 vs 200 mL, p = 0.005) and a lower incidence of remnant liver ischemia (13.3% vs 30.2%, p = 0.046). The 1- and 3-year disease-free survival rates in the ARN-FI and non-ARN-FI groups were 91.01% vs 71.15% and 70.01% vs 52.46%, respectively; the differences between the 2 groups were statistically significant (p = 0.047). CONCLUSIONS: The ARN-FI technology provides a more standardized approach for liver parenchyma section during laparoscopic liver resection, effectively minimizing intraoperative blood loss, reducing postoperative remnant liver ischemia, and improving oncological prognosis. This method is safe and feasible and has good clinical application prospects.


Assuntos
Realidade Aumentada , Carcinoma Hepatocelular , Laparoscopia , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/complicações , Verde de Indocianina , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Estudos Retrospectivos , Perda Sanguínea Cirúrgica , Hepatectomia/métodos , Laparoscopia/métodos , Imagem Óptica/métodos , Isquemia/complicações , Isquemia/cirurgia
9.
Nanomicro Lett ; 16(1): 42, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38047957

RESUMO

Metal-organic gel (MOG) derived composites are promising multi-functional materials due to their alterable composition, identifiable chemical homogeneity, tunable shape, and porous structure. Herein, stable metal-organic hydrogels are prepared by regulating the complexation effect, solution polarity and curing speed. Meanwhile, collagen peptide is used to facilitate the fabrication of a porous aerogel with excellent physical properties as well as the homogeneous dispersion of magnetic particles during calcination. Subsequently, two kinds of heterometallic magnetic coupling systems are obtained through the application of Kirkendall effect. FeCo/nitrogen-doped carbon (NC) aerogel demonstrates an ultra-strong microwave absorption of - 85 dB at an ultra-low loading of 5%. After reducing the time taken by atom shifting, a FeCo/Fe3O4/NC aerogel containing virus-shaped particles is obtained, which achieves an ultra-broad absorption of 7.44 GHz at an ultra-thin thickness of 1.59 mm due to the coupling effect offered by dual-soft-magnetic particles. Furthermore, both aerogels show excellent thermal insulation property, and their outstanding radar stealth performances in J-20 aircraft are confirmed by computer simulation technology. The formation mechanism of MOG is also discussed along with the thermal insulation and electromagnetic wave absorption mechanism of the aerogels, which will enable the development and application of novel and lightweight stealth coatings.

10.
Org Lett ; 25(45): 8127-8132, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37922337

RESUMO

We report herein a highly efficient copper-catalyzed protocol for the transformation of haloalkynes to the corresponding difluoromethylated alkynes. This scalable protocol exhibits a broad substrate scope and excellent functional group tolerance, enabling the late-stage difluoromethylation of bioactive molecules. Additionally, the strategy of utilizing the difluoromethylalkynes in gram-scale reactions and multiple transformations has proven to be highly valuable in synthetic chemistry.

11.
ACS Catal ; 13(4): 2761-2770, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-37800120

RESUMO

Despite the success of Sonogashira coupling for the synthesis of arylalkynes and conjugated enynes, the engagement of unactivated alkyl halides in such reactions remains historically challenging. We report herein a strategy that merges Cu-catalyzed alkyne transfer with the aryl radical activation of carbon-halide bonds to enable a general approach for the coupling of alkyl iodides with terminal alkynes. This unprecedented Sonogashira-type cross-coupling reaction tolerates a broad range of functional groups and has been applied to the late-stage cross-coupling of densely functionalized pharmaceutical agents as well as the synthesis of positron emission tomography tracers.

12.
Acta Biochim Pol ; 70(3): 567-574, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37721476

RESUMO

OBJECTIVE: A recent high-throughput sequencing showed that circular RNA Rho-associated kinase 1 (circROCK1) is abnormally highly expressed in sepsis, but whether it is involved in sepsis development remains unclear. The objective of this study was to investigate the biological function of circROCK1 in sepsis-induced myocardial injury and reveal its potential downstream molecular mechanism. METHODS: Real-time reverse transcriptase-polymerase chain reaction was applied to detect circROCK1 and miR-96-5p expressions in the serum of septic patients. Spearman correlation analysis examined the correlation between circROCK1 and the clinicopathological characteristics of septic patients. The Cecal puncture and ligation (CLP) method was used to establish an in vivo sepsis model. circROCK1 and miR-96-5p expressions in mice were modified by injection of lentivirus or oligonucleotide. The left ventricular systolic pressure, left ventricular end-diastolic pressure, and the maximum increase/decrease rate of left ventricular pressure were checked. ELISA was applied to detect inflammatory factors levels as well as myocardial injury markers levels. Hematoxylin and eosin staining was performed to observe pathological changes in myocardial tissues, and Western blot examined phosphorylated nuclear factor (NF)-κB and oxidative stress-responsive 1 (OXSR1) expression. Dual luciferase reporter experiment was conducted to confirm the targeting relationship between circROCK1, OXSR1, and miR-96-5p. RESULTS: circROCK1 and OXSR1 were highly expressed in sepsis and miR-96-5p was under-expressed. circROCK1 was positively correlated with serum creatinine, C-reactive protein, procalcitonin, and sequential organ failure assessment scores in septic patients. Silencing circROCK1 could improve the diastolic and systolic function of CLP mice, as well as myocardial damage, reduce myocardial tissue edema and necrosis, and inhibit inflammatory factor level and phosphorylated NF-κB expression. Down-regulating miR-96-5p promoted myocardial injury in CLP mice. Silencing circROCK1 and miR-96-5p inhibited and promoted OXSR1 expression, respectively. Both circROCK1 and OXSR1 had a targeting relationship with miR-96-5p. CONCLUSION: CircROCK1 promotes myocardial injury in septic mice by regulating the miR-96-5p/OXSR1 axis, and it can be used as a potential target for treating septic myocardial dysfunction.


Assuntos
MicroRNAs , Miocárdio , Animais , Camundongos , Western Blotting , Proteína C-Reativa , Ceco , MicroRNAs/genética
13.
Sleep Med Rev ; 72: 101842, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37660580

RESUMO

Insomnia is a common complaint for adults with multiple sclerosis and can severely impact health-related quality of life. Point prevalence estimates of insomnia are, however, difficult to determine in this population due to the use of different measurement tools as well as the highly variable clinical presentation of multiple sclerosis. This review consolidates the current evidence base to provide a global estimate of insomnia disorders and symptoms in multiple sclerosis, with consideration of both measurement and sample issues. A comprehensive review of the PUBMED, EMBASE, PsycINFO and CINAHL databases from database inception until January 31st, 2023 identified 1649 records, of which 34 (7636 participants total) were eligible for inclusion. Findings were meta-analysed using a random-effects model. Estimates based on self-reported symptoms (52%, CI: 44%-59%) were significantly higher than those obtained by diagnostic tools (22%, CI: 16%-29%). Gender was identified as a potential moderator, with women more likely to report insomnia than men. One in two adults with multiple sclerosis endorse symptoms of poor sleep quality and daytime sleepiness, with 1 in 5 diagnosed with an insomnia disorder. Future research is needed to enhance understanding of these comorbid conditions, including the trajectory of insomnia with disease progression. PROSPERO registration number CRD42021281524.


Assuntos
Distúrbios do Sono por Sonolência Excessiva , Esclerose Múltipla , Distúrbios do Início e da Manutenção do Sono , Masculino , Adulto , Humanos , Feminino , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/etiologia , Prevalência , Esclerose Múltipla/complicações , Esclerose Múltipla/epidemiologia , Qualidade de Vida , Distúrbios do Sono por Sonolência Excessiva/diagnóstico
14.
PLoS One ; 18(8): e0289963, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37566602

RESUMO

Monitoring palm tree seedlings and plantlings presents a formidable challenge because of the microscopic size of these organisms and the absence of distinguishing morphological characteristics. There is a demand for technical approaches that can provide restoration specialists with palm tree seedling monitoring systems that are high-resolution, quick, and environmentally friendly. It is possible that counting plantlings and identifying them down to the genus level will be an extremely time-consuming and challenging task. It has been demonstrated that convolutional neural networks, or CNNs, are effective in many aspects of image recognition; however, the performance of CNNs differs depending on the application. The performance of the existing CNN-based models for monitoring and predicting plantlings growth could be further improved. To achieve this, a novel Gap Layer modified CNN architecture (GL-CNN) has been proposed with an IoT effective monitoring system and UAV technology. The UAV is employed for capturing plantlings images and the IoT model is utilized for obtaining the ground truth information of the plantlings health. The proposed model is trained to predict the successful and poor seedling growth for a given set of palm tree plantling images. The proposed GL-CNN architecture is novel in terms of defined convolution layers and the gap layer designed for output classification. There are two 64×3 conv layers, two 128×3 conv layers, two 256×3 conv layers and one 512×3 conv layer for processing of input image. The output obtained from the gap layer is modulated using the ReLU classifier for determining the seedling classification. To evaluate the proposed system, a new dataset of palm tree plantlings was collected in real time using UAV technology. This dataset consists of images of palm tree plantlings. The evaluation results showed that the proposed GL-CNN model performed better than the existing CNN architectures with an average accuracy of 95.96%.

15.
Ann Surg Oncol ; 30(12): 7373-7383, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37606841

RESUMO

BACKGROUND: Laparoscopic anatomical Segment 8 (S8) resection is a highly challenging hepatectomy. Augmented reality navigation (ARN), which could be combined with indocyanine green (ICG) fluorescence imaging, has been applied in various complex liver resections and may also be applied in laparoscopic anatomical S8 resection. However, no study has explored how to apply ARN plus ICG fluorescence imaging (ARN-FI) in laparoscopic anatomical S8 resection, or explored its accuracy. PATIENTS AND METHODS: This study is a post hoc analysis that included 31 patients undergoing laparoscopic anatomical S8 resection from the clinical NaLLRFI trial, and the resected liver volume was measured in each patient. The perioperative parameters of safety and feasibility, as well as the accuracy analysis outcomes were compared. RESULTS: There were 16 patients in the ARN-FI group and 15 patients underwent conventional laparoscopic hepatectomy without ARN or fluorescence imaging (non-ARN-FI group). There was no significant difference in baseline characteristics between the two groups. Compared with the non-ARN-FI group, the ARN-FI group had lower intraoperative bleeding (median 125 vs. 300 mL, P = 0.003). No significant difference was observed in other postoperative short-term outcomes. Accuracy analysis indicated that the actual resected liver volume (ARLV) in the ARN-FI group was more accurate. CONCLUSIONS: ARN-FI was associated with less intraoperative bleeding and more accurate resection volume. These techniques may address existing challenges and provide rational guidance for laparoscopic anatomical S8 resection.

16.
Small ; 19(41): e2303393, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37291740

RESUMO

Transition metal carbide (Ti3 C2 Tx MXene), with a large specific surface area and abundant surface functional groups, is a promising candidate in the family of electromagnetic wave (EMW) absorption. However, the high conductivity of MXene limits its EMW absorption ability, so it remains a challenge to obtain outstanding EMW attenuation ability in pure MXene. Herein, by integrating HF etching, KOH shearing, and high-temperature molten salt strategies, layered MXene (L-MXene), network-like MXene nanoribbons (N-MXene NRs), porous MXene monolayer (P-MXene ML), and porous MXene layer (P-MXene L) are rationally constructed with favorable microstructures and surface states for EMW absorption. HF, KOH, and KCl/LiCl are used to functionalize MXene to tune its microstructure and surface state (F- , OH- , and Cl- terminals), thereby improving the EMW absorption capacity of MXene-based nanostructures. Impressively, with the unique structure, proper electrical conductivity, large specific surface area, and abundant porous defects, MXene-based nanostructures achieve good impedance matching, dipole polarization, and conduction loss, thus inheriting excellent EMW absorption performance. Consequently, L-MXene, N-MXene NRs, P-MXene ML, and P-MXene L enable a reflection loss (RL ) value of -43.14, -63.01, -60.45, and -56.50 dB with a matching thickness of 0.95, 1.51, 3.83, and 4.65 mm, respectively.

17.
Org Lett ; 25(25): 4632-4637, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37314942

RESUMO

Herein, by exploiting different activation modes of fluoroamides, we achieved α- and δ-C(sp3)-H alkylation of nitroalkanes with switchable regioselectivity. Cu catalysis enabled the interception of a distal C-centered radical by a N-centered radical to couple nitroalkanes and unactivated δ-C-H bonds. In addition, imines generated in situ by fluoroamides were trapped by nitroalkanes to realize the α-C-H alkylation of amides. Both of those scalable protocols have broad substrate scopes and good functional group tolerance.


Assuntos
Alcanos , Nitrocompostos , Alcanos/química , Alquilação , Nitrocompostos/química , Catálise , Amidas/química
18.
J Colloid Interface Sci ; 648: 940-950, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37329605

RESUMO

Exploring electromagnetic wave (EMW) absorbers with ultrathin matching thickness (d ≤ 1.5 mm), strong reflection loss (RL ≤ -50 dB), and wide effective absorption bandwidth (EAB, RL ≤ -10 dB) is urgent and essential for reducing EMW radiation and interference. Herein, a 2D/2D CoAl/Co9S8/Ni3S4 heterostructure was constructured using simple hydrothermal and pyrolysis methods. 2D porous CoAl nanosheets and 2D Co9S8/Ni3S4 ultrathin nanosheets are assembled by small nanoparticle chains. Strikingly, the CoAl/Co9S8/Ni3S4 heterostructure exhibits remarkable EMW absorption performance with a RL value of -61.56 dB, a high EAB of 4 GHz, and an ultrathin matching thickness of 1.25 mm. Mechanism investigations reveal that the CoAl/Co9S8/Ni3S4 heterostructure delivers dual metal sulfides behavior, high specific surface area, strong interactions, rich defects (N doping), and abundant homogeneous and heterogeneous interfaces, which promote good impedance matching, dielectric loss (interface polarization, conductive loss, and dipole polarization), as well as magnetic loss (natural resonance, exchange resonance, and eddy current loss) characteristics. This work can provide insights into the mechanism of dual metal sulfides used as high-performance EMW absorbers and deepen our understanding of the design and application of 2D/2D heterostructures.

19.
Int J Surg ; 109(4): 821-828, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37026828

RESUMO

BACKGROUND: Indocyanine green (ICG) fluorescence imaging is a new technology that can improve the real-time location of tumor edges and small nodules during surgery. However, no study has investigated its application in laparoscopic insulinoma enucleation. This study aimed to evaluate the feasibility and accuracy of this method for intraoperative localization of insulinomas and margin assessment during laparoscopic insulinoma enucleation. MATERIALS AND METHODS: Eight patients who underwent laparoscopic insulinoma enucleation from October 2016 to June 2022 were enrolled. Two methods of ICG administration, ICG dynamic perfusion and three-dimensional (3D) demarcation staining, were utilized in the laparoscopic insulinoma enucleation. Tumor-to-background ratio (TBR) and histopathologic analysis were used to evaluate the feasibility and accuracy of these novel navigation methods in laparoscopic insulinoma enucleation. RESULTS: All eight enrolled patients underwent both ICG dynamic perfusion and 3D demarcation staining. ICG dynamic perfusion images were available for six of them, among which five tumors could be recognized by TBR (largest TBR in each case 4.42±2.76), while the other could be distinguished by the disordered blood vessels in the tumor area. Seven out of eight specimens had successful 3D demarcation staining (TBR 7.62±2.62). All wound bed margins had negative frozen sections and final histopathologic diagnoses. CONCLUSIONS: ICG dynamic perfusion may be helpful in observing the abnormal vascular perfusion of tumors, providing similar functionality to intraoperative real-time angiography. ICG injection under the tumor pseudocapsule may be a useful method for acquiring real-time, 3D demarcation for the resection of insulinoma.


Assuntos
Insulinoma , Laparoscopia , Neoplasias Pancreáticas , Humanos , Verde de Indocianina , Insulinoma/diagnóstico por imagem , Insulinoma/cirurgia , Estudos Retrospectivos , Estudos de Coortes , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/cirurgia , Laparoscopia/métodos , Imagem Óptica/métodos
20.
J Gastrointest Surg ; 27(8): 1751-1752, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37095337

RESUMO

BACKGROUND: Laparoscopic right anterior sectionectomy (LRAS) is an attractive surgical option for tumors in the right anterior section (RAS), which can remove tumor-bearing segments while sparing more normal liver tissue1. However, the definition of the resection plane, the guidance during the resection, and the protection of the right posterior hepatic duct are still the key points of this procedure2. Our center attempted to use augmented reality navigation system and indocyanine green fluorescence (ICG) imaging technology to solve these difficulties3, and reported this in LRAS for the first time. METHODS: A 47-year-old female was admitted to our institution for a tumor in the RAS. Therefore, LRAS was performed. First, a virtual liver segment projection combined with the ischemic line caused by the occlusion of RAS blood flow was used to mark the RAS boundary, and it was confirmed using the ICG negative staining. Then, during the parenchymal transection, the precise resection plane was guided assisted by the ICG fluorescence imaging system. In addition, the right anterior Glissonean pedicle (RAGP) was divided using a linear stapler after confirming the spatial relationship of the bile duct using ICG fluorescence imaging. RESULTS: The operation lasted 360 min with 100 mL of intraoperative blood loss. There were no postoperative complications, and the patient was discharged after 8 days. CONCLUSION: The augmented reality navigation system plus ICG imaging can make LRAS more precisely and safely.


Assuntos
Realidade Aumentada , Carcinoma Hepatocelular , Laparoscopia , Neoplasias Hepáticas , Feminino , Humanos , Pessoa de Meia-Idade , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Verde de Indocianina , Hepatectomia/métodos , Imagem Óptica/métodos , Laparoscopia/métodos
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