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1.
J Am Chem Soc ; 146(3): 1742-1747, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38193695

RESUMEN

The proton-coupled electron transfer (PCET) mechanism for the reaction Mox-OH + e- + H+ → Mred-OH2 was determined through the kinetic resolution of the independent electron transfer (ET) and proton transfer (PT) steps. The reaction of interest was triggered by visible light excitation of [RuII(tpy)(bpy')H2O]2+, RuII-OH2, where tpy is 2,2':6',2″-terpyridine and bpy' is 4,4'-diaminopropylsilatrane-2,2'-bipyridine, anchored to In2O3:Sn (ITO) thin films in aqueous solutions. Interfacial kinetics for the PCET reduction reaction were quantified by nanosecond transient absorption spectroscopy as a function of solution pH and applied potential. Data acquired at pH = 5-10 revealed a stepwise electron transfer-proton transfer (ET-PT) mechanism, while kinetic measurements made below pKa(RuIII-OH/OH2) = 1.3 were used to study the analogous interfacial reaction, where electron transfer was the only mechanistic step. Analysis of this data with a recently reported multichannel kinetic model was used to construct a PCET zone diagram and supported the assignment of an ET-PT mechanism at pH = 5-10. Ultimately, this study represents a unique example among Mox-OH/Mred-OH2 reactivity where the protonation and oxidation states of the intermediate were kinetically and spectrally resolved to firmly establish the PCET mechanism.

2.
J Am Chem Soc ; 146(21): 14505-14520, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38743444

RESUMEN

Colloidal gold nanoparticles (AuNPs) have myriad scientific and technological applications, but their fundamental redox chemistry is underexplored. Reported here are titration studies of oxidation and reduction reactions of aqueous AuNP colloids, which show that the AuNPs bind substantial hydrogen (electrons + protons) under mild conditions. The 5 nm AuNPs are reduced to a similar extent with reductants from borohydrides to H2 and are reoxidized back essentially to their original state by oxidants, including O2. The reactions were monitored via surface plasmon resonance (SPR) optical absorption, which was shown to be much more sensitive to surface H than to changes in solution conditions. Reductions with H2 occurred without pH changes, demonstrating that hydrogenation forms surface H rather than releasing H+. Computational studies suggested that an SPR blueshift was expected for H atom addition, while just electron addition likely would have caused a redshift. Titrations consistently showed a maximum redox change of the 5 nm NPs, independent of the reagent, corresponding to 9% of the total gold or ∼30% hydrogen surface coverage (∼370 H per AuNP). Larger AuNPs showed smaller maximum fractional surface coverages. We conclude that H binds to the edge, corner, and defect sites of the AuNPs, which explains the stoichiometric limitation and the size effect. The finding of substantial and stable hydrogen on the AuNP surface under mild reducing conditions has potential implications for various applications of AuNPs in reducing environments, from catalysis to biomedicine. This finding contrasts with the behavior of bulk gold and with the typical electron-focused perspective in this field.

3.
Anal Chem ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38990771

RESUMEN

Organic Raman probes, including polymers and small molecules, have attracted great attention in biomedical imaging owing to their excellent biocompatibility. However, the development of organic Raman probes is usually hindered by a mismatch between their absorption spectra and wavelength-fixed excitation, which makes it difficult to achieve resonance excitation necessary to obtain strong Raman signals. Herein, we introduce a covalent organic framework (COF) into the fine absorption spectrum regulation of organic Raman probes, resulting in their significant Raman signal enhancement. In representative examples, a polymer poly(diketopyrrolopyrrole-p-phenylenediamine) (DPP-PD) and a small molecule azobenzene are transformed into the corresponding COF-structured Raman probes. Their absorption peaks show an accurate match of less than 5 nm with the NIR excitation. As such, the COF-structured Raman probes acquire highly sensitive bioimaging capabilities compared to their precursors with negligible signals. By further mechanism studies, we discover that the crystallinity and size of COFs directly affect the π-conjugation degree of Raman probes, thus changing their bandgaps and absorption spectra. Our study offers a universal and flexible method for improving the signal performance of organic Raman probes without changing their structural units, making it more convenient to obtain the highly sensitive organic Raman probes for in vivo bioimaging.

4.
BMC Plant Biol ; 24(1): 629, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961339

RESUMEN

Twisted trunks are not uncommon in trees, but their effects on tree growth are still unclear. Among coniferous tree species, the phenomenon of trunk distortion is more prominent in Pinus yunnanensis. To expand the germplasm of genetic resources, we selected families with excellent phenotypic traits to provide material for advanced generation breeding. The progeny test containing 93 superior families (3240 trees) was used as the research material. Phenotypic measurements and estimated genetic parameters (family heritability, realistic gain and genetic gain) were performed at 9, 15, and 18 years of age, respectively. The genetic evaluation yielded the following results (1) The intra-family variance component of plant height (PH) was greater than that of the inter-family, while the inter-family variance components of other traits (diameter at breast height (DBH), crown diameter (CD), height under branches (HUB), degree of stem-straightness (DS)) were greater than that of the intra-family, indicating that there was abundant variation among families and potential for selection. (2) At half rotation period (18 years old), there was a significant correlation among the traits. The proportion of trees with twisted trunks (level 1-3 straightness) reached 48%. The DS significantly affected growth traits, among which PH and DBH were the most affected. The volume loss rate caused by twisted trunk was 18.06-56.75%, implying that trunk distortion could not be completely eliminated after an artificial selection. (3) The influence of tree shape, crown width, and trunk on volume increased, and the early-late correlation between PH, DBH and volume was extremely significant. The range of phenotypic coefficient of variation, genetic variation coefficient and family heritability of growth traits (PH, DBH, and volume) were 44.29-127.13%, 22.88-60.87%, and 0.79-0.83, respectively. (4) A total of 21 superior families were selected by the method of membership function combined with independent selection. Compared with the mid-term selection (18 years old), the accuracy of early selection (9 years old) reached 77.5%. The selected families' genetic gain and realistic gain range were 5.79-19.82% and 7.12-24.27%, respectively. This study can provide some useful reference for the breeding of coniferous species.


Asunto(s)
Fenotipo , Pinus , Pinus/genética , Pinus/crecimiento & desarrollo , Pinus/fisiología , Árboles/crecimiento & desarrollo , Árboles/genética , Tallos de la Planta/crecimiento & desarrollo , Tallos de la Planta/genética , Tallos de la Planta/anatomía & histología , Fitomejoramiento
5.
Heart Fail Rev ; 29(1): 113-123, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37823952

RESUMEN

The progression of heart failure is reported to be strongly associated with homeostatic imbalance, such as mitochondrial dysfunction and abnormal autophagy, in the cardiomyocytes. Mitochondrial dysfunction triggers autophagic and cardiac dysfunction. In turn, abnormal autophagy impairs mitochondrial function and leads to apoptosis or autophagic cell death under certain circumstances. These events often occur concomitantly, forming a vicious cycle that exacerbates heart failure. However, the role of the crosstalk between mitochondrial dysfunction and abnormal autophagy in the development of heart failure remains obscure and the underlying mechanisms are mainly elusive. The potential role of the link between mitochondrial dysfunction and abnormal autophagy in heart failure progression has recently garnered attention. This review summarized recent advances of the interactions between mitochondria and autophagy during the development of heart failure.


Asunto(s)
Insuficiencia Cardíaca , Enfermedades Mitocondriales , Humanos , Insuficiencia Cardíaca/metabolismo , Autofagia/fisiología , Mitocondrias/metabolismo , Miocitos Cardíacos/metabolismo , Enfermedades Mitocondriales/metabolismo
6.
J Chem Phys ; 160(17)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38748016

RESUMEN

The impacting phenomenon of nanodroplets has received much attention due to their importance in various industrial applications. The oblique impingement of single droplets is well understood; however, the effect of oblique angle on impacting the dynamics of multiple droplets at the nanoscale is very limited. To address this gap, we perform molecular dynamics (MD) simulations to study the impacting dynamics of binary nanodroplets with various oblique angles (αob) and Weber numbers (We). Using MD simulations, we directly capture the detailed morphological evolution of the impacting binary droplets with various given conditions. Compared to the oblique impingement of a single droplet, the evolution of impacting binary droplets involves two novel dynamic characteristics: the asymmetric dynamics with droplet preferential spreading in the y direction and the rotating of the coalescing droplet. The mechanisms underlying are well studied. The asymmetric dynamics is a result of the velocity gradient of the outer edge of the spreading droplet, and the rotating effect is due to the change in angular momentum induced by surface force. The analysis and study of these phenomena have never been mentioned in previous studies of single droplet. Finally, we investigate the effect of αob and We on normalized moving distance (L/Dsin) and contact time (tc). This work paves the way for offering a comprehensive understanding of the oblique impingement of binary nanodroplets.

7.
Postgrad Med J ; 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38796714

RESUMEN

Cardiovascular diseases (CVDs) present a significant global public health threat, contributing to a substantial number of cases involving morbidity and mortality. Therefore, the early and accurate detection of CVDs plays an indispensable role in enhancing patient outcomes. Decades of extensive research on electrocardiography at high frequencies have yielded a wealth of knowledge regarding alterations in the QRS complex during myocardial ischemia, as well as the methodologies to assess and quantify these changes. In recent years, the analysis of high-frequency QRS (HF-QRS) components has emerged as a promising non-invasive approach for diagnosing various cardiovascular conditions. Alterations in HF-QRS amplitude and morphology have demonstrated remarkable sensitivity as diagnostic indicators for myocardial ischemia, often surpassing measures of ST-T segment changes. This comprehensive review aims to provide an intricate overview of the current advancements, challenges, and prospects associated with HF-QRS analysis in the field of CVDs.

8.
Sensors (Basel) ; 24(7)2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38610429

RESUMEN

Sequentially timed all-optical mapping photography is one of the main emerging ultra-fast detection technologies that can be widely applicable to ultra-fast detection at the picosecond level in fields such as materials and life sciences. We propose a new optical structure for an all-optical spatial mapping module that can control the optical field of two-dimensional imaging while improving spectral resolution and detector sensor utilization. The model of optical parameters based on geometrical optics theory for the given structure has been established, and the theoretical analysis of the inter-frame energy crosstalk caused by incident beam spot width, chromatic aberration, and main errors of the periscope array has been conducted. The optical design of the two-dimensional (2D) all-optical spatial mapping module was finally completed using ZEMAX OpticStudio 2018 software. The results show that our optical module can realize targets of 16 frames and 1.25 nm spectral resolution.

9.
J Environ Manage ; 353: 120172, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38310799

RESUMEN

Understanding pesticide residue patterns in crops is important for ensuring human health. However, data on residue accumulation and distribution in cowpeas grown in the greenhouse and open field are lacking. Our results suggest that acetamiprid, chlorantraniliprole, cyromazine, and thiamethoxam residues in greenhouse cowpeas were 1.03-15.32 times higher than those in open field cowpeas. Moreover, repeated spraying contributed to the accumulation of pesticide residues in cowpeas. Clothianidin, a thiamethoxam metabolite, was detected at 1.04-86.00 µg/kg in cowpeas. Pesticide residues in old cowpeas were higher than those in tender cowpeas, and the lower half of the plants had higher pesticide residues than did the upper half. Moreover, pesticide residues differed between the upper and lower halves of the same cowpea pod. Chronic and acute dietary risk assessments indicated that the human health risk was within acceptable levels of cowpea consumption. Given their high residue levels and potential accumulation, pesticides in cowpeas should be continuously assessed.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Vigna , Humanos , Tiametoxam/análisis , Tiametoxam/metabolismo , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/química , Vigna/metabolismo , Bioacumulación , Contaminación de Alimentos/análisis
10.
Int Wound J ; 21(4): e14596, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38151761

RESUMEN

Transforming Growth Factor-Beta (TGF-ß) signalling pathway is of paramount importance in the processes of wound healing, epidermal integrity maintenance and development of skin cancer. The objective of this research endeavour was to clarify the impact of gene mutations and variations in expression within TGF-ß family on mechanisms of tissue repair, as well as to identify potential targets for therapeutic purposes in non-melanoma skin cancer (NMSC). The methods utilized in this study involved obtaining RNA-seq data from 224 NMSC patients and paired normal skin tissues from the PRJNA320473 and PRJEB27606 databases. The purpose of the differential gene expression analysis was to identify genes whose expression had changed significantly. In order to evaluate the effects and interrelationships of identified gene variants, structural analysis with AlphaFold and PDB data and network analysis with the STRING database were both utilized. Critical gene expression was externally validated through the utilization of the GEPIA database. Tumour tissues exhibited a notable upregulation of genes associated with the TGF-ß pathway, specifically MMP1, MMP3, MMP9, EGF, COL3A1 and COL1A2, in comparison with normal tissues. As indicated by the central node status of these genes in the network analysis, they play a crucial role in the progression of NMSCs. The results of the structural analysis suggested that mutations might cause functional disruptions. External validation of the upregulation confirmed the expression trends and emphasized the biomarker potential of the upregulated genes. In conclusion, this research offered thorough examination of molecular modifications that occur in TGF-ß family genes, which are linked to cutaneous wound healing and NMSC. The modified expression of the identified hub genes may represent innovative targets for therapeutic intervention.


Asunto(s)
Neoplasias Cutáneas , Cicatrización de Heridas , Humanos , Cicatrización de Heridas/genética , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , Neoplasias Cutáneas/genética , Mutación , Piel/metabolismo
11.
Angew Chem Int Ed Engl ; : e202407298, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38777794

RESUMEN

Crystalline porous framework materials have attracted tremendous interest in electrocatalytic CO2 reduction owing to their ordered structures and high specific surface areas as well as rich designability, however, still suffer from a lack of accuracy in regulating the binding strength between the catalytic sites and intermediates, which is crucial for optimizing the electrocatalytic activity and expanding the product types. Herein, we report three new kinds of vinylene-linked metal-covalent organic frameworks (TMT-CH3-MCOF, TMP-CH3-MCOF and TMP-MCOF) with continuously tunable D-π-A interactions by adjusting the structure of the monomers at the molecular level for realizing efficient electroreduction of CO2 to formate for the first time. Interestingly, compared with TMT-CH3-MCOF and TMP-MCOF, the TMP-CH3-MCOF exhibited the highest HCOO- Faradaic efficiency (FEHCOO-) of 95.6 % at -1.0 V vs RHE and displayed the FEHCOO- above 90 % at the voltage range of -1.0 to -1.2 V vs. RHE, which is one of the highest among various kinds of reported electrocatalysts. Theoretical calculations further reveal that the catalytic sites in TMP-CH3-MCOF with unique moderate D-π-A interactions have suitable binding ability towards the reaction intermediate, which is beneficial for the formation of *HCOO and desorption of *HCOOH, thus effectively promoting the electroreduction of CO2 to formate.

12.
Angew Chem Int Ed Engl ; : e202407810, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38957933

RESUMEN

Hydrogen spillover in metal-supported catalysts can largely enhance electrocatalytic hydrogenation performance and reduce energy consumption. However, its fundamental mechanism, especially at the metal-metal interface, remains further explored, impeding relevant catalyst design. Here, we theoretically profile that a large free energy difference in hydrogen adsorption on two different metals (|ΔGH-metal(i) - ΔGH-metal(ii)|) induces a high kinetic barrier to hydrogen spillover between the metals. Minimizing the difference in their d-band centers (Δεd) should reduce |ΔGH-metal(i) - ΔGH-metal(ii)|, lowering the kinetic barrier to hydrogen spillover for improved electrocatalytic hydrogenation. We demonstrated this concept using copper-supported ruthenium-platinum alloys with the smallest Δεd, which delivered record high electrocatalytic nitrate hydrogenation performance, with ammonia production rate of 3.45±0.12 mmol h-1 cm-2 and Faraday efficiency of 99.8±0.2 %, at low energy consumption of 21.4 kWh kgamm-1. Using these catalysts, we further achieve continuous ammonia and formic acid production with a record high-profit space.

13.
Angew Chem Int Ed Engl ; 63(6): e202317664, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38131249

RESUMEN

Crystalline covalent triazine frameworks (CTFs) have gained considerable interest in energy and catalysis owing to their well-defined nitrogen-rich π-conjugated porosity and superior physicochemical properties, however, suffer from very limited molecular structures. Herein we report a novel solvent-free FeCl3 -catalyzed polymerization of 2, 6-pyridinedicarbonitrile (DCP) to achieve the first synthesis of crystalline, dual-porous, pyridine-based CTF (Fe-CTF). The FeCl3 could not only act as a highly active Lewis acid catalyst for promoting the two-dimensional ordered polymerization of DCP monomers, but also in situ coordinate with the tridentate chelators generated between pyridine and triazine groups to yield unique Fe-N3 single-atom active sites in Fe-CTF. Abundant few-layer crystalline nanosheets (Fe-CTF NSs) could be prepared through simple ball-milling exfoliation of the bulk layered Fe-CTF and exhibited remarkable electrocatalytic performance for oxygen reduction reaction (ORR) with a half-wave potential and onset potential up to 0.902 and 1.02 V respectively, and extraordinary Zn-air battery performance with an ultrahigh specific capacity and power density of 811 mAh g-1 and 230 mW cm-2 respectively. By combining operando X-ray absorption spectroscopy with density functional theory calculations, we revealed a dynamic and reversible evolution of Fe-N3 to Fe-N2 during the electrocatalytic process, which could further accelerate the electrocatalytic reaction.

14.
J Am Chem Soc ; 145(35): 19321-19332, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37611195

RESUMEN

The pH dependence of proton-coupled electron transfer (PCET) reactions, which are critical to many chemical and biological processes, is a powerful probe for elucidating their fundamental mechanisms. Herein, a general, multichannel kinetic model is introduced to describe the pH dependence of both homogeneous and electrochemical PCET reactions. According to this model, a weak pH dependence can arise from the competition among multiple sequential and concerted PCET channels involving different forms of the redox species, such as protonated and deprotonated forms, as well as different proton donors and acceptors. The contribution of each channel is influenced by the relative populations of the reactant species, which often depend strongly on pH, leading to complex pH dependence of PCET apparent rate constants. This model is used to explain the origins of the experimentally observed weak pH dependence of the electrochemical PCET apparent rate constant for a ruthenium-based water oxidation catalyst attached to a tin-doped In2O3 (ITO) surface. The weak pH dependence is found to arise from the intrinsic differences in the rate constants of participating channels and the dependence of their relative contributions on pH. This model predicts that the apparent maximum rate constant will become pH-independent at higher pH, which is confirmed by experimental measurements. Our analysis also suggests that the dominant channels are electron transfer at lower pH and sequential PCET via electron transfer followed by fast proton transfer at higher pH. This work highlights the importance of considering multiple competing channels simultaneously for PCET processes.

15.
Biochem Biophys Res Commun ; 643: 157-168, 2023 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-36610381

RESUMEN

RNA activation, as a method of regulating gene expression at the transcriptional level, is far less widely used than RNA interference because of the insufficient understanding of the mechanism and the unstable success rate. It is necessary to analyze the failure cases of RNA activation to promote the application of RNA activation. When we validated the saRNAs designed to induce KLK1 expression, we found that saKLK1-374 can upregulate KLK1 expression in prostate tumor cell lines, but failed in normal prostate cell lines. To determine whether the RNA activation of normal cells is difficult only when the target gene is KLK1, we tested p21WAF1/CIP1 as the target gene in RNA activation experiments of normal and cancer prostate cells. Next, to determine whether the above phenomenon exists in other tissues, we used normal and cancerous bladder cells to perform RNA activation experiments with KLK1 and p21WAF1/CIP1 as targets. We have also extended the time from transfection to detection to evaluate whether a longer incubation time can make saRNA upregulate the target genes in normal cells. Fluorescently labeled dsRNA was transfected to evaluate the transfection efficiency, and the expression of Ago2 and IPO8 necessary for RNA activation was also detected. The p21WAF1/CIP1 could be significantly upregulated by saRNA in prostate cancer cells, but not in normal prostate cells. The expression of KLK1 in bladder-derived cell lines was extremely low and could not be induced by saRNA. The p21WAF1/CIP1 was upregulated by saRNA to a higher extent in bladder cancer cells but to a lower extent in normal bladder cells. Prolonging incubation time could not make saRNA induce the expression of target genes in normal cells. Compared with tumor cells used in this study, normal cells had lower transfection efficiency or lower expression of Ago2 and IPO8. Although it has been currently found that normal cell lines in the prostate and bladder might be more difficult to be successfully induced target gene expression by exogenous saRNA than tumor cells due to low transfection efficiency or Ago2 and IPO8 expression, it is not certain that this phenomenon occurs in other types of tissue. However, researchers still need to pay attention to the transfection efficiency and/or the expression levels of Ago2 and IPO8 when conducting RNA activation experiments in normal cells.


Asunto(s)
Próstata , Neoplasias de la Próstata , Masculino , Humanos , Próstata/metabolismo , ARN Bicatenario , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Neoplasias de la Próstata/patología , Línea Celular Tumoral
16.
Opt Lett ; 48(22): 5980-5983, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37966768

RESUMEN

The inherent small divergence angle of space optical communication poses significant challenges to establishing communication links. Therefore, laser link acquisition becomes a crucial technology in optical communication, with a primary focus on reducing the acquisition time effectively. Conventional optical communication acquisition techniques fail to address the error effects caused by satellite insertion into the Earth orbit, thus unable to meet the rapid establishment demands of laser links in satellite optical communication networks. In this regard, we propose a novel, to the best of our knowledge, on-orbit calibration method for laser communication terminals to our knowledge. Leveraging stellar observations, this method achieves efficient on-orbit calibration with only a single observation. Theoretical analysis and on-orbit experimental results demonstrate that this approach effectively enhances an open-loop pointing accuracy, offering promising prospects for achieving a rapid establishment of optical communication links in ultra-long-distance optical communication missions.

17.
Chemistry ; 29(44): e202301105, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37243903

RESUMEN

An expanding body of evidence suggests that specifically targeting hydrogen sulfide (H2 S) might potentially benefit both tumor diagnosis and treatment, but there is still a lack of cancer-targeted molecular tools for in vivo applications. Here, we report the first ligand-directed H2 S-specific near-infrared fluorescent sensor PSMA-Cy7-NBD and scavenger PSMA-Py-NBD that target the prostate-specific membrane antigen (PSMA). PSMA-Cy7-NBD displays a 53-fold off-on fluorescence response to H2 S at 803 nm with high specificity. PSMA-Py-NBD can scavenge H2 S fast (k2 =30.8 M-1 s-1 at 25 °C) without interference from biothiols. Both tools are highly water-soluble and can be transported selectively into PSMA-expressing prostate cancer cells. Endogenous H2 S levels in murine 22Rv1 tumor models can be imaged and downregulated by intravenous injection of PSMA-Cy7-NBD and PSMA-Py-NBD, respectively. These tools could potentially help to investigate H2 S cancer biology and with related therapies.


Asunto(s)
Neoplasias de la Próstata , Masculino , Humanos , Animales , Ratones , Neoplasias de la Próstata/diagnóstico por imagen , Ligandos , Diagnóstico por Imagen , Línea Celular Tumoral
18.
BMC Cancer ; 23(1): 465, 2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-37210519

RESUMEN

AIM: To understand the proportion of uHCC (unresectable hepatocellular carcinoma) patients who achieve successful conversion resection in a high-volume setting with state of the art treatment options. METHODS: We retrospectively reviewed all HCC patients hospitalized to our center from June 1st, 2019 to June 1st, 2022. Conversion rate, clinicopathological features, response to systemic and/or loco-regional therapy and surgical outcomes were analyzed. RESULTS: A total of 1,904 HCC patients were identified, with 1672 patients receiving anti-HCC treatment. 328 patients were considered up-front resectable. Of the remaining 1344 uHCC patients, 311 received loco-regional treatment, 224 received systemic treatment, and the remainder (809) received combination systemic plus loco-regional treatment. Following treatment, one patient from the systemic group and 25 patients from the combination group were considered to have resectable disease. A high objective response rate (ORR) was observed in these converted patients (42.3% under RECIST v1.1 and 76.9% under mRECIST criteria). The disease control rate (DCR) reached 100%. 23 patients underwent curative hepatectomy. Major post-operative morbidity was equivalent in the both groups (P=0.76). Pathologic complete response (pCR) was 39.1%. During conversion treatment, grade 3 or higher treatment-related adverse events (TRAEs) were observed in 50% of patients. The median follow-up time was 12.9 months (range, 3.9~40.6) from index diagnosis and 11.4 months (range, 0.9~26.9) from resection. Three patients experienced disease recurrence following conversion surgery. CONCLUSIONS: By intensive treatment, a small sub-group of uHCC patients (2%) may potentially be converted to curative resection. Loco-regional combined with systemic modality was relative safe and effective in the conversion therapy. Short-term outcomes are encouraging, but long-term follow-up in a larger patient population are required to fully understand the utility of this approach.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirugía , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/patología , Estudios Retrospectivos , Recurrencia Local de Neoplasia/cirugía , Recurrencia Local de Neoplasia/patología , Terapia Combinada
19.
Eur Radiol ; 33(10): 6771-6780, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37133521

RESUMEN

OBJECTIVES: Blood flow into the side branch affects the calculation of coronary angiography-derived fractional flow reserve (FFR), called Angio-FFR. Neglecting or improperly compensating for the side branch flow may decrease the diagnostic accuracy of Angio-FFR. This study aims to evaluate the diagnostic accuracy of a novel Angio-FFR analysis that considers the side branch flow based on the bifurcation fractal law. METHODS: A one-dimensional reduced-order model based on the vessel segment was used to perform Angio-FFR analysis. The main epicardial coronary artery was divided into several segments according to the bifurcation nodes. Side branch flow was quantified using the bifurcation fractal law to correct the blood flow in each vessel segment. In order to verify the diagnostic performance of our Angio-FFR analysis, two other computational methods were taken as control groups: (i) FFR_s: FFR calculated by delineating the coronary artery tree to consider side branch flow, (ii) FFR_n: FFR calculated by just delineating the main epicardial coronary artery and neglecting the side branch flow. RESULTS: The analysis of 159 vessels from 119 patients showed that our Anio-FFR calculation method had comparable diagnostic accuracy to FFR_s and provided significantly higher diagnostic accuracy than that of FFR_n. In addition, using invasive FFR as a reference, the Pearson correlation coefficients of Angio-FFR and FFRs were 0.92 and 0.91, respectively, while that of FFR_n was only 0.85. CONCLUSIONS: Our Angio-FFR analysis has demonstrated good diagnostic performance in assessing the hemodynamic significance of coronary stenosis by using the bifurcation fractal law to compensate for side branch flow. CLINICAL RELEVANCE STATEMENT: Bifurcation fractal law can be used to compensate for side branch flow during the Angio-FFR calculation of the main epicardial vessel. Compensating for side branch flow can improve the ability of Angio-FFR to diagnose stenosis functional severity. KEY POINTS: • The bifurcation fractal law could accurately estimate the blood flow from the proximal main vessel into the main branch, thus compensating for the side branch flow. • Angiography-derived FFR based on the bifurcation fractal law is feasible to evaluate the target diseased coronary artery without delineating the side branch.


Asunto(s)
Enfermedad de la Arteria Coronaria , Estenosis Coronaria , Reserva del Flujo Fraccional Miocárdico , Humanos , Reserva del Flujo Fraccional Miocárdico/fisiología , Fractales , Angiografía Coronaria/métodos , Hemodinámica , Vasos Coronarios/diagnóstico por imagen , Índice de Severidad de la Enfermedad , Valor Predictivo de las Pruebas
20.
Purinergic Signal ; 19(1): 69-85, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35113324

RESUMEN

Our and in vitro studies had confirmed that mechanosensitive ATP release and accumulation in acupoints was elicited by acupuncture (AP), which might be a pivotal step for triggering AP analgesia. But to date, the dynamics of extracellular ATP (eATP) in the interstitial space during AP process was poorly known, mainly due to the low temporal resolution of the current detection approach. This study attempted to capture rapid eATP signals in vivo in the process of needling, and further explored the role of this eATP mobilization in initiating AP analgesic effect. Ipsilateral 20-min needling was applied on Zusanli acupoint (ST36) of complete Freund's adjuvant (CFA)-induced ankle arthritis rats. Pain thresholds were assessed in injured-side hindpaws. eATP in the interstitial space was microdialyzed and real-time quantified by luciferin-luciferase assay at 1-min interval with the aid of the microfluid chip. We revealed in behavioral tests that modulation of eATP levels in ST36 influenced AP analgesic effect on ankle arthritis. A transient eATP accumulation was induced by needling that started to mobilize at 4 min, climbed to the peak of 11.21 nM within 3.25 min and gradually recovered. Such AP-induced eATP mobilization was significantly impacted by ankle inflammation, needling depth, needle manipulation, and the presence of local ecto-nucleotidases. This work reveals that needling elicits a transient eATP mobilization in acupoints, which contributes to initiating AP analgesia. This study will help us better understand the peripheral mechanism of AP analgesia and guide clinicians to optimize the needle manipulations to improve AP efficacy.


Asunto(s)
Analgesia por Acupuntura , Terapia por Acupuntura , Artritis , Ratas , Animales , Puntos de Acupuntura , Analgésicos , Adenosina Trifosfato
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