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1.
Nature ; 590(7846): 410-415, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33597760

RESUMO

Current X-ray imaging technologies involving flat-panel detectors have difficulty in imaging three-dimensional objects because fabrication of large-area, flexible, silicon-based photodetectors on highly curved surfaces remains a challenge1-3. Here we demonstrate ultralong-lived X-ray trapping for flat-panel-free, high-resolution, three-dimensional imaging using a series of solution-processable, lanthanide-doped nanoscintillators. Corroborated by quantum mechanical simulations of defect formation and electronic structures, our experimental characterizations reveal that slow hopping of trapped electrons due to radiation-triggered anionic migration in host lattices can induce more than 30 days of persistent radioluminescence. We further demonstrate X-ray luminescence extension imaging with resolution greater than 20 line pairs per millimetre and optical memory longer than 15 days. These findings provide insight into mechanisms underlying X-ray energy conversion through enduring electron trapping and offer a paradigm to motivate future research in wearable X-ray detectors for patient-centred radiography and mammography, imaging-guided therapeutics, high-energy physics and deep learning in radiology.

2.
Nano Lett ; 24(8): 2503-2510, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38258747

RESUMO

X-ray scintillators have utility in radiation detection, therapy, and imaging. Various materials, such as halide perovskites, organic illuminators, and metal clusters, have been developed to replace conventional scintillators due to their ease of fabrication, improved performance, and adaptability. However, they suffer from self-absorption, chemical instability, and weak X-ray stopping power. Addressing these limitations, we employ alkali metal doping to turn nonemissive CsPb2Br5 into scintillators. Introducing alkali metal dopants causes lattice distortion and enhances electron-phonon coupling, which creates transient potential energy wells capable of trapping photogenerated or X-ray-generated electrons and holes to form self-trapped excitons. These self-trapped excitons undergo radiative recombination, resulting in a photoluminescence quantum yield of 55.92%. The CsPb2Br5-based X-ray scintillator offers strong X-ray stopping power, high resistance to self-absorption, and enhanced stability when exposed to the atmosphere, chemical solvents, and intense irradiation. It exhibits a detection limit of 162.3 nGyair s-1 and an imaging resolution of 21 lp mm-1.

3.
Int J Cancer ; 155(3): 582-594, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38380807

RESUMO

The proto-oncogene MYCN expression marked a cancer stem-like cell population in hepatocellular carcinoma (HCC) and served as a therapeutic target of acyclic retinoid (ACR), an orally administered vitamin A derivative that has demonstrated promising efficacy and safety in reducing HCC recurrence. This study investigated the role of MYCN as a predictive biomarker for therapeutic response to ACR and prognosis of HCC. MYCN gene expression in HCC was analyzed in the Cancer Genome Atlas and a Taiwanese cohort (N = 118). Serum MYCN protein levels were assessed in healthy controls (N = 15), patients with HCC (N = 116), pre- and post-surgical patients with HCC (N = 20), and a subset of patients from a phase 3 clinical trial of ACR (N = 68, NCT01640808). The results showed increased MYCN gene expression in HCC tumors, which positively correlated with HCC recurrence in non-cirrhotic or single-tumor patients. Serum MYCN protein levels were higher in patients with HCC, decreased after surgical resection of HCC, and were associated with liver functional reserve and fibrosis markers, as well as long-term HCC prognosis (>4 years). Subgroup analysis of a phase 3 clinical trial of ACR identified serum MYCN as the risk factor most strongly associated with HCC recurrence. Patients with HCC with higher serum MYCN levels after a 4-week treatment of ACR exhibited a significantly higher risk of recurrence (hazard ratio 3.27; p = .022). In conclusion, serum MYCN holds promise for biomarker-based precision medicine for the prevention of HCC, long-term prognosis of early-stage HCC, and identification of high-response subgroups for ACR-based treatment.


Assuntos
Biomarcadores Tumorais , Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteína Proto-Oncogênica N-Myc , Recidiva Local de Neoplasia , Proto-Oncogene Mas , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/prevenção & controle , Neoplasias Hepáticas/patologia , Proteína Proto-Oncogênica N-Myc/genética , Recidiva Local de Neoplasia/prevenção & controle , Recidiva Local de Neoplasia/sangue , Prognóstico
4.
Small ; : e2310665, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38386292

RESUMO

The development of non-precious metal-based electrodes that actively and stably support the oxygen evolution reaction (OER) in water electrolysis systems remains a challenge, especially at low pH levels. The recently published study has conclusively shown that the addition of haematite to H2 SO4 is a highly effective method of significantly reducing oxygen evolution overpotential and extending anode life. The far superior result is achieved by concentrating oxygen evolution centres on the oxide particles rather than on the electrode. However, unsatisfactory Faradaic efficiencies of the OER and hydrogen evolution reaction (HER) parts as well as the required high haematite load impede applicability and upscaling of this process. Here it is shown that the same performance is achieved with three times less metal oxide powder if NiO/H2 SO4 suspensions are used along with stainless steel anodes. The reason for the enormous improvement in OER performance by adding NiO to the electrolyte is the weakening of the intramolecular O─H bond in the water molecules, which is under the direct influence of the nickel oxide suspended in the electrolyte. The manipulation of bonds in water molecules to increase the tendency of the water to split is a ground-breaking development, as shown in this first example.

5.
Nat Mater ; 22(3): 289-304, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36864164

RESUMO

Persistent luminescent phosphors can store light energy in advance and release it with a long-lasting afterglow emission. With their ability to eliminate in situ excitation and store energy for long periods of time, they are promising for broad applications, including background-free bioimaging, high-resolution radiography, conformal electronics imaging and multilevel encryption. This Review provides an overview of various strategies for trap manipulation in persistent luminescent nanomaterials. We highlight key examples in the design and preparation of nanomaterials with tunable persistent luminescence, particularly in the near-infrared range. In subsequent sections, we cover the most current developments and trends concerning the use of these nanomaterials in biological applications. Moreover, we assess their advantages and disadvantages compared with conventional luminescent materials for biological applications. We also discuss future research directions and challenges, such as insufficient brightness at the single-particle level, and possible solutions to these challenges.

6.
World J Urol ; 42(1): 302, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720010

RESUMO

PURPOSE: To evaluate the diagnostic performance of contrast-enhanced (CE) ultrasound using Sonazoid (SNZ-CEUS) by comparing with contrast-enhanced computed tomography (CE-CT) and contrast-enhanced magnetic resonance imaging (CE-MRI) for differentiating benign and malignant renal masses. MATERIALS AND METHODS: 306 consecutive patients (from 7 centers) with renal masses (40 benign tumors, 266 malignant tumors) diagnosed by both SNZ-CEUS, CE-CT or CE-MRI were enrolled between September 2020 and February 2021. The examinations were performed within 7 days, but the sequence was not fixed. Histologic results were available for 301 of 306 (98.37%) lesions and 5 lesions were considered benign after at least 2 year follow-up without change in size and image characteristics. The diagnostic performances were evaluated by sensitivity, specificity, positive predictive value, negative predictive value, and compared by McNemar's test. RESULTS: In the head-to-head comparison, SNZ-CEUS and CE-MRI had comparable sensitivity (95.60 vs. 94.51%, P = 0.997), specificity (65.22 vs. 73.91%, P = 0.752), positive predictive value (91.58 vs. 93.48%) and negative predictive value (78.95 vs. 77.27%); SNZ-CEUS and CE-CT showed similar sensitivity (97.31 vs. 96.24%, P = 0.724); however, SNZ-CEUS had relatively lower than specificity than CE-CT (59.09 vs. 68.18%, P = 0.683). For nodules > 4 cm, CE-MRI demonstrated higher specificity than SNZ-CEUS (90.91 vs. 72.73%, P = 0.617) without compromise the sensitivity. CONCLUSIONS: SNZ-CEUS, CE-CT, and CE-MRI demonstrate desirable and comparable sensitivity for the differentiation of renal mass. However, the specificity of all three imaging modalities is not satisfactory. SNZ-CEUS may be a suitable alternative modality for patients with renal dysfunction and those allergic to gadolinium or iodine-based agents.


Assuntos
Meios de Contraste , Compostos Férricos , Ferro , Neoplasias Renais , Imageamento por Ressonância Magnética , Óxidos , Tomografia Computadorizada por Raios X , Ultrassonografia , Humanos , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Ultrassonografia/métodos , Tomografia Computadorizada por Raios X/métodos , Imageamento por Ressonância Magnética/métodos , Idoso , Diagnóstico Diferencial , Adulto , Idoso de 80 Anos ou mais
7.
Chem Rev ; 122(6): 5519-5603, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-34989556

RESUMO

Impurity doping is a promising method to impart new properties to various materials. Due to their unique optical, magnetic, and electrical properties, rare-earth ions have been extensively explored as active dopants in inorganic crystal lattices since the 18th century. Rare-earth doping can alter the crystallographic phase, morphology, and size, leading to tunable optical responses of doped nanomaterials. Moreover, rare-earth doping can control the ultimate electronic and catalytic performance of doped nanomaterials in a tunable and scalable manner, enabling significant improvements in energy harvesting and conversion. A better understanding of the critical role of rare-earth doping is a prerequisite for the development of an extensive repertoire of functional nanomaterials for practical applications. In this review, we highlight recent advances in rare-earth doping in inorganic nanomaterials and the associated applications in many fields. This review covers the key criteria for rare-earth doping, including basic electronic structures, lattice environments, and doping strategies, as well as fundamental design principles that enhance the electrical, optical, catalytic, and magnetic properties of the material. We also discuss future research directions and challenges in controlling rare-earth doping for new applications.


Assuntos
Metais Terras Raras , Nanoestruturas , Metais Terras Raras/química , Nanoestruturas/química
8.
Environ Sci Technol ; 58(22): 9815-9827, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38768015

RESUMO

Tropical small island developing states (SIDS), with their geographical isolation and limited resources, heavily rely on the fisheries industry for food and revenue. The presence of marine lipophilic phycotoxins (MLPs) poses risks to their economy and human health. To understand the contamination status and potential risks, the Republic of Kiribati was selected as the representative tropical SIDS and 55 species of 256 coral reef fish encompassing multiple trophic levels and feeding strategies were collected to analyze 17 typical MLPs. Our results showed that the potential risks of ciguatoxins were the highest and approximately 62% of fish species may pose risks for consumers. Biomagnification of ciguatoxins was observed in the food web with a trophic magnification factor of 2.90. Brevetoxin-3, okadaic acid, and dinophysistoxin-1 and -2 were first reported, but the risks posed by okadaic acid and dinophysistoxins were found to be negligible. The correlation analysis revealed that fish body size and trophic position are unreliable metrics to indicate the associated risks and prevent the consumption of contaminated fish. The potential risks of MLPs in Kiribati are of concern, and our findings can serve as valuable inputs for developing food safety policies and fisheries management strategies specific to tropical SIDS contexts.


Assuntos
Peixes , Toxinas Marinhas , Animais , Cadeia Alimentar , Ilhas , Humanos , Medição de Risco , Clima Tropical , Ciguatoxinas/toxicidade
9.
Environ Res ; 244: 117934, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38109957

RESUMO

Florfenicol, as a replacement for chloramphenicol, can tightly bind to the A site of the 23S rRNA in the 50S subunit of the 70S ribosome, thereby inhibiting protein synthesis and bacterial proliferation. Due to the widespread use in aquaculture and veterinary medicine, florfenicol has been detected in the aquatic environment worldwide. Concerns over the effects and health risks of florfenicol on target and non-target organisms have been raised in recent years. Although the ecotoxicity of florfenicol has been widely reported in different species, no attempt has been made to review the current research progress of florfenicol toxicity, hormesis, and its health risks posed to biota. In this study, a comprehensive literature review was conducted to summarize the effects of florfenicol on various organisms including bacteria, algae, invertebrates, fishes, birds, and mammals. The generation of antibiotic resistant bacteria and spread antibiotic resistant genes, closely associated with hormesis, are pressing environmental health issues stemming from overuse or misuse of antibiotics including florfenicol. Exposure to florfenicol at µg/L-mg/L induced hormetic effects in several algal species, and chromoplasts might serve as a target for florfenicol-induced effects; however, the underlying molecular mechanisms are completely lacking. Exposure to high levels (mg/L) of florfenicol modified the xenobiotic metabolism, antioxidant systems, and energy metabolism, resulting in hepatotoxicity, renal toxicity, immunotoxicity, developmental toxicity, reproductive toxicity, obesogenic effects, and hormesis in different animal species. Mitochondria and the associated energy metabolism are suggested to be the primary targets for florfenicol toxicity in animals, albeit further in-depth investigations are warranted for revealing the long-term effects (e.g., whole-life-cycle impacts, multigenerational effects) of florfenicol, especially at environmental levels, and the underlying mechanisms. This will facilitate the evaluation of potential hormetic effects and construction of adverse outcome pathways for environmental risk assessment and regulation of florfenicol.


Assuntos
Antibacterianos , Tianfenicol , Tianfenicol/análogos & derivados , Animais , Antibacterianos/toxicidade , Tianfenicol/toxicidade , Cloranfenicol/farmacologia , Bactérias , Mamíferos
10.
Ecotoxicol Environ Saf ; 269: 115788, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38056118

RESUMO

The contamination of arable land with heavy metals, such as Cd, is a serious concern worldwide. Intercropping with Cd accumulators can be used for efficient safe crop production and phytoremediation of Cd-contaminated soil. However, the effect of intercropping on Cd uptake by main crops and accumulators varies among plant combinations. Rhizosphere interaction may mediate Cd uptake by intercropped plants, but the mechanism is unclear. Thus, in the present study, we aimed to examine the effect of rhizosphere interaction on Cd uptake by intercropping rice (Oryza sativa L.) with mugwort (Artemisia argyi Levl. et Vant.) in Cd-contaminated paddy soil. We grew O. sativa and A. argyi in pots designed to allow different levels of interaction: complete root interaction (no barrier), partial root interaction (nylon mesh barrier), and no root interaction (plastic film barrier). Our results indicated that both complete and partial root interaction increased the shoot and root mass of A. argyi, but did not decrease the shoot, root, and grain mass of O. sativa. Interspecific root interaction significantly increased the Cd content in the shoots, roots, and grains of O. sativa and the shoots of A. argyi. Increased content of total organic acids in the rhizosphere, which increased the content of available Cd, was a possible mechanism of increased Cd uptake in both plants under interspecific root interaction. Our findings demonstrate that an intercropping system can extract more Cd from contaminated soil than a monocropping system of either A. argyi or O. sativa. However, the intercropping system did not facilitate safe crop production because it substantially increased grain Cd content in O. sativa.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Solo , Raízes de Plantas/química , Grão Comestível/química , Biodegradação Ambiental , Poluentes do Solo/análise
11.
Nano Lett ; 23(3): 979-984, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36652276

RESUMO

Trivalent lanthanides are commonly incorporated into sodium yttrium fluoride nanocrystals to enhance their optical properties. Lanthanides are expected to randomly replace trivalent yttrium cations due to their isovalent nature, and the dopant-dopant distance decreases with increasing dopant concentration. Combining spectroscopy with quantum mechanical calculations, we find that large lanthanides exhibit an anisotropic distribution in the hexagonal yttrium sublattice at low dopant concentrations. This counterintuitive substitution suggests the formation of one-dimensional dimers or chains with short dopant-dopant distances. Our study of the distance-sensitive cross-relaxation between Nd3+ dopants in ß-NaYF4 nanocrystals confirms that the concentration quenching threshold is lower than that of their cubic counterparts, consistent with the proposed chain-like model. Moreover, we demonstrate modulation of the anisotropic distribution by microstrain management via alkali metal codoping. Research into dopant distribution in inorganic crystals may enable the development of new materials and properties for future challenges.

12.
Angew Chem Int Ed Engl ; 63(25): e202404177, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38634766

RESUMO

Long-lasting radioluminescence scintillators have recently attracted substantial attention from both research and industrial communities, primarily due to their distinctive capabilities of converting and storing X-ray energy. However, determination of energy-conversion kinetics in these nanocrystals remains unexplored. Here we present a strategy to probe and unveil energy-funneling kinetics in NaLuF4:Mn2+/Gd3+ nanocrystal sublattices through Gd3+-driven microenvironment engineering and Mn2+-mediated radioluminescence profiling. Our photophysical studies reveal effective control of energy-funneling kinetics and demonstrate the tunability of electron trap depth ranging from 0.66 to 0.96 eV, with the corresponding trap density varying between 2.38×105 and 1.34×107 cm-3. This enables controlled release of captured electrons over durations spanning from seconds to 30 days. It allows tailorable emission wavelength within the range of 520-580 nm and fine-tuning of thermally-stimulated temperature between 313-403 K. We further utilize these scintillators to fabricate high-density, large-area scintillation screens that exhibit a 6-fold improvement in X-ray sensitivity, 22 lp/mm high-resolution X-ray imaging, and a 30-day-long optical memory. This enables high-contrast imaging of injured mice through fast thermally-stimulated radioluminescence readout. These findings offer new insights into the correlation of radioluminescence dynamics with energy-funneling kinetics, thereby contributing to the advancement of high-energy nanophotonic applications.

13.
Artigo em Inglês | MEDLINE | ID: mdl-36787166

RESUMO

A novel endophytic bacterium, designated strain BGMRC 0089T, was isolated from a surface-sterilized root of Sonneratia apetala. Cells were observed to be Gram-negative, rod-shaped and motile with polar flagella. Strain BGMRC 0089T was found to grow optimally at 28-30 °C, pH 7.0-8.0 and in the presence of 1 % (w/v) NaCl. Strain BGMRC 0089T contained ubiquinone Q-10 and the predominant fatty acid was summed feature 8. The polar lipid profile of strain BGMRC 0089T was found to contain diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmonomethylethanolamine and phosphatidylethanolamine. Based on the results of 16S rRNA gene analysis, this isolate has the closest phylogenetic relationships with Rhizobium lemnae L6-16T (96.5 %) and Allorhizobium oryziradicis N19T (96.4 %). Average nucleotide identity, amino acid identity and digital DNA-DNA hybridization values of the isolate with the type strains of the genera Rhizobium and Allorhizobium were below 84.6, 73.9 and 22.1  %, respectively. Analysis the 4.55 Mb draft genome of strain BGMRC 0089T revealed several plant-associated genes, which may play important roles for the plant in the adaptation to the mangrove habitat. Based on its distinct phylogenetic, phenotypic and chemotaxonomic characteristics, strain BGMRC 0089T is proposed to represent a novel Allorhizobium species, for which the name Allorhizobium sonneratiae sp. nov. is proposed (type strain BGMRC 0089T=DSM 100171T=MCCC 1K04805T).


Assuntos
Ácidos Graxos , Rhizobium , Ácidos Graxos/química , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Composição de Bases , DNA Bacteriano/genética , Rhizobium/genética , China
14.
Artigo em Inglês | MEDLINE | ID: mdl-37022760

RESUMO

A taxonomic study was carried out on strain BGMRC 0090T, which was isolated from seawater. The isolate was a Gram-negative, aerobic, flagellated, rod-shaped bacterium with algicidal activity. Optimal growth was observed at 30 °C, pH 6.0 and with 2 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain BGMRC 0090T belonged to the genus Parvularcula, with highest sequence similarity to Parvularcula lutaonensis CC-MMS-1T (98.4 %). Average nucleotide identity, amino acid identity and digital DNA-DNA hybridization values between strain BGMRC 0090T and five strains of the genus Parvularcula with publicly available genomes were below 84.0, 69.2 and 21.4 %, respectively. The genome of strain BGMRC 0090T was 3.2 Mb with 64.8 mol% DNA G+C content and encoded 2905 predicted proteins, three rRNA, 42 tRNA and four ncRNA genes. Some algicidal biosynthesis-associated genes were detected in the genome. Strain BGMRC 0090T contained Q-10 as the major quinone. The predominant fatty acids were identified as summed feature 8 (C18 : 1ω7c/ω6c) and C16 : 0. Based on the polyphasic evidence presented in this paper, strain BGMRC 0090T is concluded to represent a novel species of the genus Parvularcula, for which the name Parvularcula maris sp. nov. is proposed. The type strain is BGMRC 0090T (= KCTC 92591T=MCCC 1K08100T).


Assuntos
Ácidos Graxos , Fosfolipídeos , Ácidos Graxos/química , Filogenia , Fosfolipídeos/química , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Composição de Bases , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Água do Mar/microbiologia
15.
Eur Radiol ; 33(3): 1895-1905, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36418624

RESUMO

OBJECTIVES: To develop and validate a deep learning (DL) model based on quantitative analysis of contrast-enhanced ultrasound (CEUS) images that predicts early recurrence (ER) after thermal ablation (TA) of colorectal cancer liver metastasis (CRLM). METHODS: Between January 2010 and May 2019, a total of 207 consecutive patients with CRLM with 13,248 slice images at three dynamic phases who received CEUS within 2 weeks before TA were retrospectively enrolled in two centres (153 for the training cohort (TC), 32 for the internal test cohort (ITC), and 22 for the external test cohort (ETC)). Clinical and CEUS data were used to develop and validate the clinical model, DL model, and DL combining with clinical (DL-C) model to predict ER after TA. The performance of these models was compared by the receiver operating characteristic curve (ROC) with the DeLong test. RESULTS: After a median follow-up of 56 months, 49% (99/207) of patients experienced ER. Three key clinical features (preoperative chemotherapy (PC), lymph node metastasis of the primary colorectal cancer (LMPCC), and T stage) were used to develop the clinical model. The DL model yielded better performance than the clinical model in the ETC (AUC: 0.67 for the clinical model, 0.76 for the DL model). The DL-C model significantly outperformed the clinical model and DL model (AUC: 0.78 for the DL-C model in the ETC; both, p < 0.001). CONCLUSIONS: The model based on CEUS can achieve satisfactory prediction and assist physicians during the therapeutic decision-making process in clinical practice. KEY POINTS: • This is an exploratory study in which ablation-related contrast-enhanced ultrasound (CEUS) data from consecutive patients with colorectal cancer liver metastasis (CRLM) were collected simultaneously at multiple institutions. • The deep learning combining with clinical (DL-C) model provided desirable performance for the prediction of early recurrence (ER) after thermal ablation (TA). • The DL-C model based on CEUS provides guidance for TA indication selection and making therapeutic decisions.


Assuntos
Neoplasias Colorretais , Aprendizado Profundo , Neoplasias Hepáticas , Humanos , Estudos Retrospectivos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Ultrassonografia/métodos , Metástase Linfática
16.
Surg Endosc ; 37(5): 3567-3579, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36624217

RESUMO

BACKGROUND: Postoperative pancreatic fistula (POPF) is often associated with significant morbidity and mortality after the Whipple operation. Patient-related factors associated with POPF include soft pancreatic texture and a small main pancreatic duct (MPD). The traditional duct-to-mucosa anastomosis was modified to be easily performed. The aim of the study was to evaluate the simplified pancreaticojejunostomy (PJ) method in the prevention of POPF after minimally invasive pancreaticoduodenectomy (PD). METHODS: Ninety-eight patients who underwent laparoscopic pancreaticoduodenectomy (LPD) and robotic pancreaticoduodenectomy (RPD) with a simplified PJ procedure containing only two duct-to-mucosa sutures and four penetrating-sutures to anastomose the pancreatic parenchyma and jejunal seromuscular layer in our center were retrospectively studied. Demographics and clinical short-term safety were assessed. RESULTS: All LPD and RPD procedures were successfully performed. The median time of PJ was 17 min, and the median blood loss was 60 mL, with only one patient requiring transfusion. Four patients (4.1%) suffered from clinically relevant POPF (CR-POPF), including four grade B cases and no grade C cases. For patients with an MPD diameter of 3 mm or less, POPF was noted in two (4%) of the fifty patients, with all cases being grade B. Of the patients with a soft pancreas, only two (4.5%) patients suffered from grade B POPF. One patient (1.0%) experienced a 90-day mortality. Neither the main pancreatic diameter nor pancreatic texture had an impact on postoperative outcomes. CONCLUSIONS: Our technique is a simple, safe and efficient alternative to prevent POPF after LPD and RPD. This method is suitable for almost all pancreatic conditions, including cases with a small main pancreatic duct and soft pancreas, and has the potential to become the preferred procedure in low-volume pancreatic surgery centers. Our modified duct-to-mucosa PJ, which contains only two duct-to-mucosa sutures and four penetrating-sutures to anastomose the pancreatic parenchyma and jejunal seromuscular layer, is ideal for small MPD and soft pancreas when performing minimally invasive PD and has a low rate of POPF. PJ pancreaticojejunostomy, MPD main pancreatic diameter, PD pancreaticoduodenectomy, POPF postoperative pancreatic fistula.


Assuntos
Pancreaticoduodenectomia , Pancreaticojejunostomia , Humanos , Pancreaticojejunostomia/métodos , Pancreaticoduodenectomia/métodos , Fístula Pancreática/etiologia , Fístula Pancreática/prevenção & controle , Fístula Pancreática/cirurgia , Estudos Retrospectivos , Pâncreas/cirurgia , Ductos Pancreáticos/cirurgia , Anastomose Cirúrgica/métodos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/cirurgia , Mucosa
17.
J Nanobiotechnology ; 21(1): 307, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37644442

RESUMO

A disorder of cholesterol homeostasis is one of the main initiating factors in the progression of atherosclerosis (AS). Metabolism and removal of excess cholesterol facilitates the prevention of foam cell formation. However, the failure of treatment with drugs (e.g. methotrexate, MTX) to effectively regulate progression of disease may be related to the limited drug bioavailability and rapid clearance by immune system. Thus, based on the inflammatory lesion "recruitment" properties of macrophages, MTX nanoparticles (MTX NPs) camouflaged with macrophage membranes (MM@MTX NPs) were constructed for the target to AS plaques. MM@MTX NPs exhibited a uniform hydrodynamic size around ~ 360 nm and controlled drug release properties (~ 72% at 12 h). After the macrophage membranes (MM) functionalized "homing" target delivery to AS plaques, MM@MTX NPs improved the solubility of cholesterol by the functionalized ß-cyclodextrin (ß-CD) component and significantly elevate cholesterol efflux by the loaded MTX mediated the increased expression levels of ABCA1, SR-B1, CYP27A1, resulting in efficiently inhibiting the formation of foam cells. Furthermore, MM@MTX NPs could significantly reduce the area of plaque, aortic plaque and cholesterol crystals deposition in ApoE-/- mice and exhibited biocompatibility. It is suggested that MM@MTX NPs were a safe and efficient therapeutic platform for AS.


Assuntos
Aterosclerose , Placa Aterosclerótica , Animais , Camundongos , Células Espumosas , Biomimética , Aterosclerose/tratamento farmacológico , Transporte Biológico
18.
Ecotoxicol Environ Saf ; 263: 115242, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37441949

RESUMO

Erythromycin (ERY) is a typical macrolide antibiotic with large production and extensive use on a global scale. Detection of ERY in both freshwaters and coaster seawaters, as well as relatively high ecotoxicity of ERY have been documented. Notably, hormesis has been reported on several freshwater algae under ERY stress, where growth was promoted at relatively lower exposures but inhibited at higher treatment levels. On the contrary, there is limited information of ERY toxicity in marine algae, hampering the risk assessment on ERY in the coaster waters. The presence of hormesis may challenge the current concept of dose-response adopted in chemical risk assessment. Whether and how exposure to ERY can induce dose-dependent toxicity in marine algae remain virtually unknown, especially at environmentally relevant concentrations. The present study used a model marine diatom Thalassiosira weissflogii (T. weissflogii) to reveal its toxicological responses to ERY at different biological levels and decipher the underlying mechanisms. Assessment of multiple apical endpoints shows an evident growth promotion following ERY exposure at an environmentally relevant concentration (1 µg/L), associated with increased contents reactive oxygen species (ROS) and chlorophyll-a (Chl-a), activated signaling pathways related to ribosome biosynthesis and translation, and production of total soluble protein. By contrast, growth inhibition in the 750 and 2500 µg/L treatments was attributed to reduced viability, increased ROS formation, reduced content of total soluble protein, inhibited photosynthesis, and perturbed signaling pathways involved in xenobiotic metabolism, ribosome, metabolism of amino acid, and nitrogen metabolism. Measurements of multiple apical endpoints coupled with de novo transcriptomics analysis applied in the present study, a systems biology approach, can generate detailed mechanistic information of chemical toxicity including dose-response and species sensitivity difference used in environmental risk assessment.


Assuntos
Diatomáceas , Eritromicina , Eritromicina/toxicidade , Diatomáceas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Hormese , Antibacterianos/toxicidade
19.
J Environ Sci (China) ; 127: 336-348, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36522066

RESUMO

Benzo[a]pyrene (BaP), a ubiquitous pollutant, raises environmental health concerns due to induction of bone toxicity in the unexposed offspring. Exposure of F0 ancestor medaka (Oryzias latipes) to 1 µg/L BaP for 21 days causes reduced vertebral bone thickness in the unexposed F3 male offspring. To reveal the inherited modifications, osteoblast (OB) abundance and molecular signaling pathways of transgenerational BaP-induced bone thinning were assessed. Histomorphometric analysis showed a reduction in OB abundance. Analyses of the miRNA and mRNA transcriptomes revealed the dysregulation of Wnt signaling (frzb/ola-miR-1-3p, sfrp5/ola-miR-96-5p/miR-455-5p) and bone morphogenetic protein (Bmp) signaling (bmp3/ola-miR-96-5p/miR-181b-5p/miR-199a-5p/miR-205-5p/miR-455-5p). Both pathways are major indicators of impaired bone formation, while the altered Rank signaling in osteoclasts (c-fos/miR-205-5p) suggests a potentially augmented bone resorption. Interestingly, a typical BaP-responsive pathway, the Nrf2-mediated oxidative stress response (gst/ola-miR-181b-5p/miR-199a-5p/miR-205), was also affected. Moreover, mRNA levels of epigenetic modification enzymes (e.g., hdac6, hdac7, kdm5b) were found dysregulated. The findings indicated that epigenetic factors (e.g., miRNAs, histone modifications) may directly regulate the expression of genes associated with transgenerational BaP bone toxicity and warrants further studies. The identified candidate genes and miRNAs may serve as potential biomarkers for BaP-induced bone disease and as indicators of historic exposures in wild fish for conservation purposes.


Assuntos
MicroRNAs , Oryzias , Poluentes Químicos da Água , Animais , Masculino , Oryzias/fisiologia , Benzo(a)pireno/toxicidade , Benzo(a)pireno/análise , Benzo(a)pireno/metabolismo , Transcriptoma , Poluentes Químicos da Água/análise , RNA Mensageiro , MicroRNAs/metabolismo
20.
J Am Chem Soc ; 144(36): 16366-16377, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36037283

RESUMO

Activation of the stimulator of interferon genes (STING) is essential for blocking viral infections and eliciting antitumor immune responses. Local injection of synthetic STING agonists, such as 2'3'-cGAMP [cGAMP = cyclic 5'-guanosine monophosphate (cGMP)-adenosine monophosphate (AMP)], is a promising approach to enhance antiviral functions and cancer immunotherapy. However, the application of such agonists has been hindered by complicated synthetic procedures, high doses, and unsatisfactory systemic immune responses. Herein, we report the design and synthesis of a series of 2'3'-cGAMP surrogates in nanoparticle formulations formed by reactions of AMP, GMP, and coordinating lanthanides. These nanoparticles can stimulate the type-I interferon (IFN) response in both mouse macrophages and human monocytes. We further demonstrate that the use of europium-based nanoparticles as STING-targeted adjuvants significantly promotes the maturation of mouse bone-marrow-derived dendritic cells and major histocompatibility complex class I antigen presentation. Dynamic molecular docking analysis revealed that these nanoparticles bind with high affinity to mouse STING and human STING. Compared with soluble ovalbumin (OVA), subcutaneously immunized europium-based nanovaccines exhibit significantly increased production of primary and secondary anti-OVA antibodies (∼180-fold) in serum, as well as IL-5 (∼28-fold), IFN-γ (∼27-fold), and IFN-α/ß (∼4-fold) in splenocytes ex vivo. Compared with the 2'3'-cGAMP/OVA formulation, subcutaneous administration of nanovaccines significantly inhibits B16F10-OVA tumor growth and prolongs the survival of tumor-bearing mice in both therapeutic and protective models. Given the rich supramolecular chemistry with lanthanides, this work will enable a readily accessible platform for potent humoral and cellular immunity while opening new avenues for cost-effective, highly efficient therapeutic delivery of STING agonists.


Assuntos
Interferon Tipo I , Elementos da Série dos Lantanídeos , Proteínas de Membrana/metabolismo , Nanopartículas , Neoplasias , Monofosfato de Adenosina , Animais , Európio , Humanos , Interferon Tipo I/genética , Interferon Tipo I/metabolismo , Interferon beta , Camundongos , Simulação de Acoplamento Molecular , Neoplasias/terapia , Nucleotídeos , Nucleotídeos Cíclicos/farmacologia , Ovalbumina
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