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1.
World J Gastroenterol ; 30(25): 3166-3178, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-39006386

RESUMO

BACKGROUND: Integrating conventional ultrasound features with 2D shear wave elastography (2D-SWE) can potentially enhance preoperative hepatocellular carcinoma (HCC) predictions. AIM: To develop a 2D-SWE-based predictive model for preoperative identification of HCC. METHODS: A retrospective analysis of 884 patients who underwent liver resection and pathology evaluation from February 2021 to August 2023 was conducted at the Oriental Hepatobiliary Surgery Hospital. The patients were divided into the modeling group (n = 720) and the control group (n = 164). The study included conventional ultrasound, 2D-SWE, and preoperative laboratory tests. Multiple logistic regression was used to identify independent predictive factors for malignant liver lesions, which were then depicted as nomograms. RESULTS: In the modeling group analysis, maximal elasticity (Emax) of tumors and their peripheries, platelet count, cirrhosis, and blood flow were independent risk indicators for malignancies. These factors yielded an area under the curve of 0.77 (95% confidence interval: 0.73-0.81) with 84% sensitivity and 61% specificity. The model demonstrated good calibration in both the construction and validation cohorts, as shown by the calibration graph and Hosmer-Lemeshow test (P = 0.683 and P = 0.658, respectively). Additionally, the mean elasticity (Emean) of the tumor periphery was identified as a risk factor for microvascular invasion (MVI) in malignant liver tumors (P = 0.003). Patients receiving antiviral treatment differed significantly in platelet count (P = 0.002), Emax of tumors (P = 0.033), Emean of tumors (P = 0.042), Emax at tumor periphery (P < 0.001), and Emean at tumor periphery (P = 0.003). CONCLUSION: 2D-SWE's hardness value serves as a valuable marker for enhancing the preoperative diagnosis of malignant liver lesions, correlating significantly with MVI and antiviral treatment efficacy.


Assuntos
Carcinoma Hepatocelular , Técnicas de Imagem por Elasticidade , Neoplasias Hepáticas , Fígado , Humanos , Técnicas de Imagem por Elasticidade/métodos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Fígado/diagnóstico por imagem , Fígado/patologia , Fígado/cirurgia , Valor Preditivo dos Testes , Hepatectomia , Nomogramas , Adulto , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Fatores de Risco , Sensibilidade e Especificidade
2.
Opt Express ; 32(11): 19655-19664, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859095

RESUMO

A cost-effective method to achieve a 2-3 µm wavelength light source on silicon represents a major challenge. In this study, we have developed a novel approach that combines an epitaxial growth and the ion-slicing technique. A 2.1 µm wavelength laser on a wafer-scale heterogeneous integrated InP/SiO2/Si (InPOI) substrate fabricated by ion-slicing technique was achieved by epitaxial growth. The performance of the lasers on the InPOI are comparable with the InP, where the threshold current density (Jth) was 1.3 kA/cm2 at 283 K when operated under continuous wave (CW) mode. The high thermal conductivity of Si resulted in improved high-temperature laser performance on the InPOI. The proposed method offers a novel means of integrating an on-chip light source.

3.
Dis Esophagus ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38881278

RESUMO

The study aimed to describe the prevalence of lymph node metastases per lymph node station for esophageal squamous cell carcinoma (ESCC) after neoadjuvant treatment. Clinicopathological variables of ESCC patients were retrieved from the prospective database of the Surgical Esophageal Cancer Patient Registry in West China Hospital, Sichuan University. A two-field lymphadenectomy was routinely performed, and an extensive three-field lymphadenectomy was performed if cervical lymph node metastasis was suspected. According to AJCC/UICC 8, lymph node stations were investigated separately. The number of patients with metastatic lymph nodes divided by those who underwent lymph node dissection at that station was used to define the percentage of patients with lymph node metastases. Data are also separately analyzed according to the pathological response of the primary tumor, neoadjuvant treatment regimens, pretreatment tumor length, and tumor location. Between January 2019 and March 2023, 623 patients who underwent neoadjuvant therapy followed by transthoracic esophagectomy were enrolled. Lymph node metastases were found in 212 patients (34.0%) and most frequently seen in lymph nodes along the right recurrent nerve (10.1%, 58/575), paracardial station (11.4%, 67/587), and lymph nodes along the left gastric artery (10.9%, 65/597). For patients with pretreatment tumor length of >4 cm and non-pathological complete response of the primary tumor, the metastatic rate of the right lower cervical paratracheal lymph nodes is 10.9% (10/92) and 10.6% (11/104), respectively. For patients with an upper thoracic tumor, metastatic lymph nodes were most frequently seen along the right recurrent nerve (14.2%, 8/56). For patients with a middle thoracic tumor, metastatic lymph nodes were most commonly seen in the right lower cervical paratracheal lymph nodes (10.3%, 8/78), paracardial lymph nodes (10.2%, 29/285), and lymph nodes along the left gastric artery (10.4%, 30/289). For patients with a lower thoracic tumor, metastatic lymph nodes were most frequently seen in the paracardial station (14.2%, 35/247) and lymph nodes along the left gastric artery (13.1%, 33/252). The study precisely determined the distribution of lymph node metastases in ESCC after neoadjuvant treatment, which may help to optimize the extent of lymphadenectomy in the surgical management of ESCC patients after neoadjuvant therapy.

4.
Front Cell Infect Microbiol ; 14: 1358801, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895732

RESUMO

Background: Rapid and accurate diagnosis of the causative agents is essential for clinical management of bloodstream infections (BSIs) that might induce sepsis/septic shock. A considerable number of suspected sepsis patients initially enter the health-care system through an emergency department (ED), hence it is vital to establish an early strategy to recognize sepsis and initiate prompt care in ED. This study aimed to evaluate the diagnostic performance and clinical value of droplet digital PCR (ddPCR) assay in suspected sepsis patients in the ED. Methods: This was a prospective single-centered observational study including patients admitted to the ED from 25 October 2022 to 3 June 2023 with suspected BSIs screened by Modified Shapiro Score (MSS) score. The comparison between ddPCR and blood culture (BC) was performed to evaluate the diagnostic performance of ddPCR for BSIs. Meanwhile, correlative analysis between ddPCR and the inflammatory and prognostic-related biomarkers were conducted to explore the relevance. Further, the health economic evaluation of the ddPCR was analyzed. Results: 258 samples from 228 patients, with BC and ddPCR performed simultaneously, were included in this study. We found that ddPCR results were positive in 48.13% (103 of 214) of episodes, with identification of 132 pathogens. In contrast, BC only detected 18 positives, 88.89% of which were identified by ddPCR. When considering culture-proven BSIs, ddPCR shows an overall sensitivity of 88.89% and specificity of 55.61%, the optimal diagnostic power for quantifying BSI through ddPCR is achieved with a copy cutoff of 155.5. We further found that ddPCR exhibited a high accuracy especially in liver abscess patients. Among all the identified virus by ddPCR, EBV has a substantially higher positive rate with a link to immunosuppression. Moreover, the copies of pathogens in ddPCR were positively correlated with various markers of inflammation, coagulation, immunity as well as prognosis. With high sensitivity and specificity, ddPCR facilitates precision antimicrobial stewardship and reduces health care costs. Conclusions: The multiplexed ddPCR delivers precise and quantitative load data on the causal pathogen, offers the ability to monitor the patient's condition and may serve as early warning of sepsis in time-urgent clinical situations as ED. Importance: Early detection and effective administration of antibiotics are essential to improve clinical outcomes for those with life-threatening infection in the emergency department. ddPCR, an emerging tool for rapid and sensitive pathogen identification used as a precise bedside test, has developed to address the current challenges of BSI diagnosis and precise treatment. It characterizes sensitivity, specificity, reproducibility, and absolute quantifications without a standard curve. ddPCR can detect causative pathogens and related resistance genes in patients with suspected BSIs within a span of three hours. In addition, it can identify polymicrobial BSIs and dynamically monitor changes in pathogenic microorganisms in the blood and can be used to evaluate antibiotic efficacy and survival prognosis. Moreover, the copies of pathogens in ddPCR were positively correlated with various markers of inflammation, coagulation, immunity. With high sensitivity and specificity, ddPCR facilitates precision antimicrobial stewardship and reduces health care costs.


Assuntos
Diagnóstico Precoce , Serviço Hospitalar de Emergência , Reação em Cadeia da Polimerase , Sepse , Humanos , Estudos Prospectivos , Sepse/diagnóstico , Sepse/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Reação em Cadeia da Polimerase/métodos , Sensibilidade e Especificidade , Biomarcadores/sangue , Hemocultura/métodos , Adulto
5.
Acta Pharmacol Sin ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789494

RESUMO

Excessive dietary calories lead to systemic metabolic disorders, disturb hepatic lipid metabolism, and aggravate nonalcoholic steatohepatitis (NASH). Bile acids (BAs) play key roles in regulating nutrition absorption and systemic energy homeostasis. Resmetirom is a selective thyroid hormone receptor ß (THRß) agonist and the first approved drug for NASH treatment. It is well known that the THRß activation could promote intrahepatic lipid catabolism and improve mitochondrial function, however, its effects on intestinal lipid absorption and BA compositions remain unknown. In the present study, the choline-deficient, L-amino acid defined, high-fat diet (CDAHFD) and high-fat diet plus CCl4 (HFD+CCl4)-induced NASH mice were used to evaluate the effects of resmetirom on lipid and BA composition. We showed that resmetirom administration (10 mg·kg-1·d-1, i.g.) significantly altered hepatic lipid composition, especially reduced the C18:2 fatty acyl chain-containing triglyceride (TG) and phosphatidylcholine (PC) in the two NASH mouse models, suggesting that THRß activation inhibited intestinal lipid absorption since C18:2 fatty acid could be obtained only from diet. Targeted analysis of BAs showed that resmetirom treatment markedly reduced the hepatic and intestinal 12-OH to non-12-OH BAs ratio by suppressing cytochrome P450 8B1 (CYP8B1) expression in both NASH mouse models. The direct inhibition by resmetirom on intestinal lipid absorption was further verified by the BODIPY gavage and the oral fat tolerance test. In addition, disturbance of the altered BA profiles by exogenous cholic acid (CA) supplementation abolished the inhibitory effects of resmetirom on intestinal lipid absorption in both normal and CDAHFD-fed mice, suggesting that resmetirom inhibited intestinal lipid absorption by reducing 12-OH BAs content. In conclusion, we discovered a novel mechanism of THRß agonists on NASH treatment by inhibiting intestinal lipid absorption through remodeling BAs composition, which highlights the multiple regulation of THRß activation on lipid metabolism and extends the current knowledge on the action mechanisms of THRß agonists in NASH treatment.

6.
J Hazard Mater ; 473: 134693, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38781855

RESUMO

Persistent cadmium exposure poses significant health risks to the Chinese population, underscored by its prevalence as an environmental contaminant. This study leverages a machine-learning model, fed with a comprehensive dataset of environmental and socio-economic factors, to delineate trends in cadmium exposure from 1980 to 2040. We uncovered that urinary cadmium levels peaked at 1.09 µg/g Cr in the mid-2000 s. Encouragingly, a decline is projected to 0.92 µg/g Cr by 2025, tapering further to 0.87 µg/g Cr by 2040. Despite this trend, regions heavily influenced by industrialization, such as Hunan and Guizhou, as well as industrial counties in Jilin, report stubbornly high levels of exposure. Our demographic analysis reveals a higher vulnerability among adults & adolescents over 14, with males displaying elevated cadmium concentrations. Alarmingly, the projected data suggests that by 2040, an estimated 41% of the population will endure exposure beyond the safety threshold set by the European Food Safety Authority. Our research indicates disproportionate cadmium exposure impacts, necessitating targeted interventions and policy reforms to protect vulnerable groups and public health in China.


Assuntos
Cádmio , Exposição Ambiental , Cádmio/urina , China , Humanos , Masculino , Adulto , Adolescente , Adulto Jovem , Feminino , Exposição Ambiental/análise , Criança , Pessoa de Meia-Idade , Pré-Escolar , Poluentes Ambientais/urina , Idoso , Lactente , Análise Espaço-Temporal , Aprendizado de Máquina
7.
Toxicol Pathol ; : 1926233241248656, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38742644

RESUMO

Emerging urinary kidney safety biomarkers have been evaluated in recent years and have been shown to be superior to the serum parameters blood urea nitrogen (BUN) and creatinine (sCr) for monitoring kidney injury in the proximal tubule. However, their potential application in differentiating the location of the initial kidney injury (eg, glomerulus vs tubule) has not been fully explored. Here, we assessed the performance of two algorithms that were constructed using either an empirical or a mathematical model to predict the site of kidney injury using a data set consisting of 22 rat kidney toxicity studies with known urine biomarker and histopathologic outcomes. Two kidney safety biomarkers used in both models, kidney injury molecule 1 (KIM-1) and albumin (ALB), were the best performers to differentiate glomerular injury from tubular injury. The performance of algorithms using these two biomarkers against the gold standard of kidney histopathologic examination showed high sensitivity in differentiating the location of the kidney damage to either the glomerulus or the proximal tubules. These data support the exploration of such an approach for use in clinical settings, leveraging urinary biomarker data to aid in the diagnosis of either glomerular or tubular injury where histopathologic assessments are not conducted.

8.
Anal Chem ; 96(21): 8458-8466, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38710075

RESUMO

G-triplexes are G-rich oligonucleotides composed of three G-tracts and have absorbed much attention due to their potential biological functions and attractive performance in biosensing. Through the optimization of loop compositions, DNA lengths, and 5'-flanking bases of G-rich sequences, a new stable G-triplex sequence with 14 bases (G3-F15) was discovered to dramatically activate the fluorescence of Thioflavin T (ThT), a water-soluble fluorogenic dye. The fluorescence enhancement of ThT after binding with G3-F15 reached 3200 times, which was the strongest one by far among all of the G-rich sequences. The conformations of G3-F15 and G3-F15/ThT were studied by circular dichroism. The thermal stability measurements indicated that G3-F15 was a highly stable G-triplex structure. The conformations of G3-F15 and G3-F15/ThT in the presence of different metal cations were studied thoroughly by fluorescent spectroscopy, circular dichroism, and nuclear magnetic resonance. Furthermore, using the G3-F15/ThT complex as a fluorescent probe, a robust and simple turn-on fluorescent sensor for uracil-DNA glycosylase activity was developed. This study proposes a new systematic strategy to explore new functional G-rich sequences and their ligands, which will promote their applications in diagnosis, therapy, and biosensing.


Assuntos
Benzotiazóis , DNA , Corantes Fluorescentes , Uracila-DNA Glicosidase , Benzotiazóis/química , Benzotiazóis/metabolismo , Corantes Fluorescentes/química , DNA/química , DNA/metabolismo , Uracila-DNA Glicosidase/metabolismo , Uracila-DNA Glicosidase/química , Espectrometria de Fluorescência , Fluorescência , Técnicas Biossensoriais/métodos , Dicroísmo Circular , Humanos
9.
Adv Sci (Weinh) ; 11(25): e2402272, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38639395

RESUMO

Here, a photocatalytic asymmetric multicomponent cascade Minisci reaction of ß-carbolines with enamides and diazo compounds is reported, enabling an effective enantioselective radical C─H functionalization of ß-carbolines with high yields and enantioselectivity (up to 83% yield and 95% ee). This enantioselective multicomponent Minisci protocol exhibits step economy, high chemo-/enantio-selective control, and good functional group tolerance, allowing access to a variety of valuable chiral ß-carbolines. Notably, diazo compounds are suitable radical precursors in enantioselective cascade radical reactions. Moreover, the efficiency and practicality of this approach are demonstrated by the asymmetric synthesis of bioactive compounds and natural products.

11.
Exp Cell Res ; 438(1): 114047, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38631546

RESUMO

BACKGROUND: Programmed death ligand-1(PD-L1) has been postulated to play a crucial role in the regulation of barrier functions of the vascular endothelium, yet how this novel molecule mediates dysfunction in endothelial cells (ECs) during acute lung injury (ALI) remains largely unknown. METHODS: PD-L1 siRNA and plasmids were synthesized and applied respectively to down- or up-regulate PD-L1 expression in human lung microvascular endothelial cells (HMVECs). RNA sequencing was used to explore the differentially expressed genes following PD-L1 overexpression. The expression levels of tight junction proteins (ZO-1 and occludin) and the signaling pathways of NLRP-3/caspase-1/pyroptosis were analyzed. A mouse model of indirect ALI was established through hemorrhagic shock (HEM) followed by cecal ligation and puncture (CLP), enabling further investigation into the effects of intravenous delivery of PD-L1 siRNA. RESULTS: A total of 1502 differentially expressed genes were identified, comprising 532 down-regulated and 970 up-regulated genes in ECs exhibiting PD-L1overexpression. Enrichment of PD-L1-correlated genes were observed in the NOD-like receptor signaling pathway and the TNF signaling pathway. Western blot assays confirmed that PD-L1 overexpression elevated the expression of NLRP3, cleaved-caspase-1, ASC and GSDMD, and concurrently diminished the expression of ZO-1 and occludin. This overexpression also enhanced mitochondrial oxidative phosphorylation and mitochondrial reactive oxygen species (mtROS) production. Interestingly, mitigating mitochondrial dysfunction with mitoQ partially countered the adverse effects of PD-L1 on the functionality of ECs. Furthermore, intravenous administration of PD-L1 siRNA effectively inhibited the activation of the NLRP3 inflammasome and pyroptosis in pulmonary ECs, subsequently ameliorating lung injury in HEM/CLP mice. CONCLUSION: PD-L1-mediated activation of the inflammasome contributes significantly to the disruption of tight junction and induction of pyroptosis in ECs, where oxidative stress associated with mitochondrial dysfunction serves as a pivotal mechanism underpinning these effects.


Assuntos
Antígeno B7-H1 , Caspase 1 , Endotélio Vascular , Proteína 3 que Contém Domínio de Pirina da Família NLR , Piroptose , Transdução de Sinais , Animais , Humanos , Masculino , Camundongos , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/genética , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Caspase 1/metabolismo , Caspase 1/genética , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Mitocôndrias/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Piroptose/genética , Espécies Reativas de Oxigênio/metabolismo
12.
Biol Trace Elem Res ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630343

RESUMO

Population-based studies on the association between cadmium (Cd) exposure and thyroid function are limited and have shown conflicting results. Two independent cross-sectional studies using different Cd biomarkers were carried out in six rural areas with different soil Cd levels in China. Thyroid dysfunction was defined based on levels of thyroid stimulating hormone (TSH) and free thyroxine (FT4). Multivariable linear regression, multiple logistic regression, and restrictive cubic splines models were used to estimate the association between Cd and thyroid dysfunction. For both of the two independent studies, higher Cd levels were observed to be associated with lower TSH levels and higher risk of thyroid dysfunction. The negative relationship between urinary Cd and TSH was found in both total participants (ß = - 0.072, p = 0.008) and males (ß = - 0.119, p = 0.020) but not in females; however, the negative relationship between blood Cd and TSH was only found in females (ß = - 0.104, p = 0.024). Higher urinary Cd was associated with higher risk of thyroid dysfunction (OR = 1.77, p = 0.031), while higher blood Cd was associated with higher risk of thyroid dysfunction (OR = 1.95, p = 0.011). Results from the two independent cross-sectional studies consistently suggested that higher Cd levels were associated with sex-specific thyroid dysfunction.

13.
J Agric Food Chem ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598840

RESUMO

Sarcoplasmic calcium-binding protein (Cra a 4) from Crassostrea angulata belongs to the EF-hand superfamily, and understanding of its structure-allergenicity relationship is still insufficient. In this study, chemical denaturants were used to destroy the structure of Cra a 4, showing that disruption of the structure reduced its IgG-/IgE-binding activity. To explore which critical amino acid site affects the allergenicity of Cra a 4, the mutants were obtained by site-directed mutations in the disulfide bonds site (C97), conformational epitopes (I105, D114), or Ca2+-binding region (D106, D110) and their IgG-/IgE-binding activity was reduced significantly using serological tests. Notably, C97A had the lowest immunoreactivity. In addition, two conformational epitopes of Cra 4 were verified. Meanwhile, the increase of the α-helical content, surface hydrophobicity, and surface electrostatic potential of C97A affected its allergenicity. Overall, the understanding of the structure-allergenicity relationship of Cra a 4 allowed the development of a hypoallergenic mutant.

14.
Neuroreport ; 35(6): 343-351, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38526969

RESUMO

Inflammatory pain, the most prevalent disease globally, remains challenging to manage. Electroacupuncture emerges as an effective therapy, yet its underlying mechanisms are not fully understood. This study investigates whether adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)-regulated silent information regulator 1 (SIRT1) contributes to electroacupuncture's antinociceptive effects by modulating macrophage/microglial polarization in the spinal dorsal horn of a mouse model of inflammatory pain. In this study, mice, introduced to inflammatory pain through subcutaneous injections of complete freund's adjuvant (CFA) in the plantar area, underwent electroacupuncture therapy every alternate day for 30-min sessions. The assessment of mechanical allodynia and thermal hyperalgesia in these subjects was carried out using paw withdrawal frequency and paw withdrawal latency measurements, respectively. Western blot analysis measured levels of AMPK, phosphorylation-adenosine 5'-monophosphate (AMP)-activated protein kinase, SIRT1, inducible nitric oxide synthase, cluster of differentiation 86, arginase 1, and interleukin 10. In contrast to the group treated solely with CFA, the cohort receiving both CFA and electroacupuncture demonstrated notable decreases in both thermal hyperalgesia and mechanical allodynia. This was accompanied by a marked enhancement in AMPK phosphorylation levels. AMPK knockdown reversed electroacupuncture's analgesic effects and reduced M2 macrophage/microglial polarization enhancement. Additionally, AMPK knockdown significantly weakened electroacupuncture-induced SIRT1 upregulation, and EX-527 injection attenuated electroacupuncture's facilitation of M2 macrophage/microglial polarization without affecting AMPK phosphorylation levels. Furthermore, combining electroacupuncture with SRT1720 enhanced the analgesic effect of SRT1720. Our findings suggest that AMPK regulation of SIRT1 plays a critical role in electroacupuncture's antinociceptive effect through the promotion of M2 macrophage/microglial polarization.


Assuntos
Eletroacupuntura , Hiperalgesia , Humanos , Ratos , Camundongos , Animais , Hiperalgesia/terapia , Hiperalgesia/induzido quimicamente , Proteínas Quinases Ativadas por AMP/uso terapêutico , Microglia , Sirtuína 1 , Ratos Sprague-Dawley , Dor/induzido quimicamente , Analgésicos/uso terapêutico , Adenosina , Macrófagos , Inflamação/induzido quimicamente
15.
Proc Natl Acad Sci U S A ; 121(14): e2319233121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38547064

RESUMO

Chemical transformations near plasmonic metals have attracted increasing attention in the past few years. Specifically, reactions occurring within plasmonic nanojunctions that can be detected via surface and tip-enhanced Raman (SER and TER) scattering were the focus of numerous reports. In this context, even though the transition between localized and nonlocal (quantum) plasmons at nanojunctions is documented, its implications on plasmonic chemistry remain poorly understood. We explore the latter through AFM-TER-current measurements. We use two molecules: i) 4-mercaptobenzonitrile (MBN) that reports on the (non)local fields and ii) 4-nitrothiophenol (NTP) that features defined signatures of its neutral/anionic forms and dimer product, 4,4'-dimercaptoazobenzene (DMAB). The transition from classical to quantum plasmons is established through our optical measurements: It is marked by molecular charging and optical rectification. Simultaneously recorded force and current measurements support our assignments. In the case of NTP, we observe the parent and DMAB product beneath the probe in the classical regime. Further reducing the gap leads to the collapse of DMAB to form NTP anions. The process is reversible: Anions subsequently recombine into DMAB. Our results have significant implications for AFM-based TER measurements and their analysis, beyond the scope of this work. In effect, when precise control over the junction is not possible (e.g., in SER and ambient TER), both classical and quantum plasmons need to be considered in the analysis of plasmonic reactions.

16.
Sheng Wu Gong Cheng Xue Bao ; 40(3): 921-930, 2024 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-38545987

RESUMO

Pantoea alhagi NX-11 exopolysaccharide (PAPS) is a novel microbial biostimulant that enhances crop resistance to salt and drought stress. It is biodegradable and holds promising applications in improving agricultural yield and efficiency. However, the fermentation process of PAPS exhibits a high viscosity due to low oxygen transfer efficiency, which hinders yield improvement and downstream processing. This study aimed to investigate the effects of seven oxygen carriers (Span 80, Span 20, Tween 80, Tween 20, glycerin, olive oil, and soybean oil) on fermentation yield. The results showed that the addition of 0.5% (V/V) Tween 20 significantly enhanced the production of PAPS. Moreover, the introduction of 0.5% (V/V) Tween 20 in a 7.5 L fermenter resulted in a PAPS titer of (16.85±0.50) g/L, which was 17.70% higher than that of the control group. Furthermore, the rheological characterization and the microstructure analysis of the polysaccharide products revealed that the characteristic structure of polysaccharides remained unchanged in the oxygen carrier treated group, but their viscosity increased. These findings may facilitate enhancing the biosynthesis efficiency of other polymer products.


Assuntos
Pantoea , Polissorbatos , Polissorbatos/química , Polissacarídeos , Oxigênio
17.
Int J Mol Sci ; 25(6)2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38542356

RESUMO

Nucleic acid modifications play important roles in biological activities and disease occurrences, and have been considered as cancer biomarkers. Due to the relatively low amount of nucleic acid modifications in biological samples, it is necessary to develop sensitive and reliable qualitative and quantitative methods to reveal the content of any modifications. In this review, the key processes affecting the qualitative and quantitative analyses are discussed, such as sample digestion, nucleoside extraction, chemical labeling, chromatographic separation, mass spectrometry detection, and data processing. The improvement of the detection sensitivity and specificity of analytical methods based on mass spectrometry makes it possible to study low-abundance modifications and their biological functions. Some typical nucleic acid modifications and their potential as biomarkers are displayed, and efforts to improve diagnostic accuracy are discussed. Future perspectives are raised for this research field.


Assuntos
Ácidos Nucleicos , Espectrometria de Massas/métodos , Biomarcadores Tumorais
19.
Int J Comput Assist Radiol Surg ; 19(5): 903-915, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38472690

RESUMO

PURPOSE: Progression of hip osteoarthritis (hip OA) leads to pain and disability, likely leading to surgical treatment such as hip arthroplasty at the terminal stage. The severity of hip OA is often classified using the Crowe and Kellgren-Lawrence (KL) classifications. However, as the classification is subjective, we aimed to develop an automated approach to classify the disease severity based on the two grades using digitally-reconstructed radiographs from CT images. METHODS: Automatic grading of the hip OA severity was performed using deep learning-based models. The models were trained to predict the disease grade using two grading schemes, i.e., predicting the Crowe and KL grades separately, and predicting a new ordinal label combining both grades and representing the disease progression of hip OA. The models were trained in classification and regression settings. In addition, the model uncertainty was estimated and validated as a predictor of classification accuracy. The models were trained and validated on a database of 197 hip OA patients, and externally validated on 52 patients. The model accuracy was evaluated using exact class accuracy (ECA), one-neighbor class accuracy (ONCA), and balanced accuracy. RESULTS: The deep learning models produced a comparable accuracy of approximately 0.65 (ECA) and 0.95 (ONCA) in the classification and regression settings. The model uncertainty was significantly larger in cases with large classification errors ( P < 6 e - 3 ). CONCLUSIONS: In this study, an automatic approach for grading hip OA severity from CT images was developed. The models have shown comparable performance with high ONCA, which facilitates automated grading in large-scale CT databases and indicates the potential for further disease progression analysis. Classification accuracy was correlated with the model uncertainty, which would allow for the prediction of classification errors. The code will be made publicly available at https://github.com/NAIST-ICB/HipOA-Grading .


Assuntos
Aprendizado Profundo , Osteoartrite do Quadril , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Humanos , Osteoartrite do Quadril/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Incerteza , Progressão da Doença
20.
Environ Res ; 251(Pt 1): 118618, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38442819

RESUMO

Despite the significant threat of cadmium exposure in China, a national-level assessment has been conspicuously absent. This study bridges this critical gap by collecting, geospatial analyzing and multivariable regression analyzing published studies on urinary cadmium levels in Chinese from 1982 to 2021. Our research reveals a notable decline trend in cadmium exposure among Chinese populations. However, this trend varies by region, age and gender group, higher levels are seen in the South (1.04 µg/g cr) compared to the North (0.48 µg/g cr), and in adults (1.08 µg/g cr) relative to children (0.33 µg/g cr), with higher levels being more pronounced in females (6.17 µg/g cr). Urinary cadmium is significantly correlated with rice consumption (P < 0.001), while mining activities have been identified as the dominant factor for cadmium exposure in most regions of China, a trend that is evident both in past decades and is expected to continue into the next decade. These findings underscore the need for region-specific environmental and public health strategies, designed to effectively address the distinct cadmium exposure risks in various regions and among different population groups, thus enhancing protection against the adverse effects of cadmium.


Assuntos
Cádmio , Exposição Ambiental , Cádmio/urina , Cádmio/análise , China , Humanos , Feminino , Masculino , Criança , Exposição Ambiental/análise , Poluentes Ambientais/urina , Poluentes Ambientais/análise , Adulto , Pré-Escolar , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Lactente , Monitoramento Ambiental
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