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1.
Adv Mater ; : e2405892, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39036824

RESUMEN

Implantable bioelectronic devices, designed for both monitoring and modulating living organisms, require functional and biological adaptability. Pure silk is innovatively employed, which is known for its excellent biocompatibility, to engineer water-triggered, geometrically reconfigurable membranes, on which functions can be integrated by Micro Electro Mechanical System (MEMS) techniques and specially functionalized silk. These devices can undergo programmed shape deformations within 10 min once triggered by water, and thus establishing stable bioelectronic interfaces with natively fitted geometries. As a testament to the applicability of this approach, a twining peripheral nerve electrode is designed, fabricated, and rigorously tested, demonstrating its efficacy in nerve modulation while ensuring biocompatibility for successful implantation.

2.
Med Biol Eng Comput ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38898202

RESUMEN

Medical image segmentation commonly involves diverse tissue types and structures, including tasks such as blood vessel segmentation and nerve fiber bundle segmentation. Enhancing the continuity of segmentation outcomes represents a pivotal challenge in medical image segmentation, driven by the demands of clinical applications, focusing on disease localization and quantification. In this study, a novel segmentation model is specifically designed for retinal vessel segmentation, leveraging vessel orientation information, boundary constraints, and continuity constraints to improve segmentation accuracy. To achieve this, we cascade U-Net with a long-short-term memory network (LSTM). U-Net is characterized by a small number of parameters and high segmentation efficiency, while LSTM offers a parameter-sharing capability. Additionally, we introduce an orientation information enhancement module inserted into the model's bottom layer to obtain feature maps containing orientation information through an orientation convolution operator. Furthermore, we design a new hybrid loss function that consists of connectivity loss, boundary loss, and cross-entropy loss. Experimental results demonstrate that the model achieves excellent segmentation outcomes across three widely recognized retinal vessel segmentation datasets, CHASE_DB1, DRIVE, and ARIA.

3.
Sci Bull (Beijing) ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38910106

RESUMEN

Many clustered regularly interspaced short palindromic repeat and CRISPR-associated protein 12b (CRISPR-Cas12b) nucleases have been computationally identified, yet their potential for genome editing remains largely unexplored. In this study, we conducted a GFP-activation assay screening 13 Cas12b nucleases for mammalian genome editing, identifying five active candidates. Candidatus hydrogenedentes Cas12b (ChCas12b) was found to recognize a straightforward WTN (W = T or A) proto-spacer adjacent motif (PAM), thereby dramatically expanding the targeting scope. Upon optimization of the single guide RNA (sgRNA) scaffold, ChCas12b exhibited activity comparable to SpCas9 across a panel of nine endogenous loci. Additionally, we identified nine mutations enhancing ChCas12b specificity. More importantly, we demonstrated that both ChCas12b and its high-fidelity variant, ChCas12b-D496A, enabled allele-specific disruption of genes harboring single nucleotide polymorphisms (SNPs). These data position ChCas12b and its high-fidelity counterparts as promising tools for both fundamental research and therapeutic applications.

4.
Sci Bull (Beijing) ; 69(14): 2231-2240, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-38851911

RESUMEN

Perovskite light-emitting diodes (PeLEDs) exhibit remarkable potential in the field of displays and solid-state lighting. However, blue PeLEDs, a key element for practical applications, still lag behind their green and red counterparts, due to a combination of strong nonradiative recombination losses and unoptimized device structures. In this report, we propose a buried interface modification strategy to address these challenges by focusing on the bottom-hole transport layer (HTL) of the PeLEDs. On the one hand, a multifunctional molecule, aminoacetic acid hydrochloride (AACl), is introduced to modify the HTL/perovskite interface to regulate the perovskite crystallization. Experimental investigations and theoretical calculations demonstrate that AACl can effectively reduce the nonradiative recombination losses in bulk perovskites by suppressing the growth of low-n perovskite phases and also the losses at the bottom interface by passivating interfacial defects. On the other hand, a self-assembly nanomesh structure is ingeniously developed within the HTLs. This nanomesh structure is meticulously crafted through the blending of poly-(9,9-dioctyl-fluorene-co-N-(4-butyl phenyl) diphenylamine) and poly (n-vinyl carbazole), significantly enhancing the light outcoupling efficiency in PeLEDs. As a result, our blue PeLEDs achieve remarkable external quantum efficiencies, 20.4% at 487 nm and 12.5% at 470 nm, which are among the highest reported values. Our results offer valuable insights and effective methods for achieving high-performance blue PeLEDs.

5.
Otol Neurotol ; 45(7): e509-e516, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38918071

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate the value of asymmetry values, gain, and pathological saccades of the video head impulse test (vHIT) in sudden sensorineural hearing loss (SSNHL). STUDY DESIGN: Retrospective study. SETTING: Tertiary referral center. PATIENTS: A total of 226 individuals diagnosed with unilateral definite SSNHL were hospitalized. The assessment included a comprehensive evaluation of medical history, pure-tone test, acoustic impedance, positional test, video nystagmography (VNG), vHIT, vestibular evoked myogenic potentials (VEMPs) and magnetic resonance. INTERVENTIONS: vHIT, VNG, cVEMP, oVEMP. Statistical analysis was performed with SPSS version 22.0 for Windows. MAIN OUTCOME MEASURES: The asymmetry values, gain, and pathological saccades of the vHIT. RESULTS: The abnormal gain of vHIT in anterior, horizontal, and posterior canal in SSNHL patients with vertigo were revealed in 20 of 112 (17.9%), 24 of 112 (21.4%), and 60 of 112 (53.6%), respectively. The vHIT pathological saccades (overt + covert) of anterior, horizontal, and posterior canal in SSNHL patients with vertigo were observed in 5 of 112 (4.6%), 52 of 112 (46.4%), and 58 of 112 (51.8%), respectively. Multivariate analysis indicated that the prognosis of patients with vertigo was correlated with vHIT gain of posterior canal, pathological saccade in horizontal canal, asymmetric ratio of horizontal canal gain, asymmetric ratio of posterior canal gain, Canal paresis (%) on caloric test and spontaneous nystagmus. CONCLUSION: In the vHIT of patients with SSNHL with vertigo, the posterior canal is most easily affected. Reduced gain of posterior canal, pathological saccade of horizontal canal, and larger asymmetric gain of posterior canal and horizontal canal may be negative prognostic factors.


Asunto(s)
Prueba de Impulso Cefálico , Pérdida Auditiva Sensorineural , Pérdida Auditiva Súbita , Movimientos Sacádicos , Potenciales Vestibulares Miogénicos Evocados , Humanos , Prueba de Impulso Cefálico/métodos , Masculino , Femenino , Persona de Mediana Edad , Adulto , Movimientos Sacádicos/fisiología , Estudios Retrospectivos , Pérdida Auditiva Sensorineural/fisiopatología , Pérdida Auditiva Sensorineural/diagnóstico , Anciano , Pérdida Auditiva Súbita/fisiopatología , Pérdida Auditiva Súbita/diagnóstico , Potenciales Vestibulares Miogénicos Evocados/fisiología , Adolescente , Vértigo/fisiopatología , Vértigo/diagnóstico , Adulto Joven , Imagen por Resonancia Magnética , Anciano de 80 o más Años
6.
Acta Radiol ; 65(7): 700-707, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38856151

RESUMEN

BACKGROUND: Focal liver lesions (FLLs) are a common form of liver disease, and identifying accurate pathological types is required to guide treatment and evaluate prognosis. PURPOSE: To compare and analyze the application effect of contrast-enhanced ultrasound (CEUS) and conventional ultrasound (US) in the clinical diagnosis of focal liver lesions. MATERIAL AND METHODS: A retrospective analysis was performed on 682 patients with space-occupying liver lesions admitted to our hospital between December 2015 and August 2021. Of these, 280 underwent CEUS-guided biopsies and 402 underwent conventional US biopsies, with the results of each biopsy subsequently compared between the two groups. The success rate and accuracy of the biopsies and their relationship with different pathological features were also analyzed. RESULTS: The success rate, sensitivity, diagnostic accuracy, positive predictive value, and negative predictive value of the CEUS group were significantly higher than those of the US group (P < 0.05). Lesion size accuracy in the CEUS group was significantly higher than that in the US group (89.29% vs. 40.55%; P < 0.05). Lesion type accuracy in the CEUS group was significantly higher than that in the US group (86.49% vs. 43.59%), and the difference between the two groups was statistically significant (P < 0.05). The logistic regression analysis indicated that malignant lesions, lesions ≥5 cm, and lesions ≤1 cm were independent factors affecting the success rate of the puncture procedure (P < 0.05). CONCLUSION: The sensitivity, specificity, and diagnostic accuracy of lesion size and type in the CEUS group were higher than those in the US group.


Asunto(s)
Medios de Contraste , Sensibilidad y Especificidad , Ultrasonografía , Humanos , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Ultrasonografía/métodos , Adulto , Anciano , Hígado/diagnóstico por imagen , Hígado/patología , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/patología , Hepatopatías/diagnóstico por imagen , Hepatopatías/patología , Aumento de la Imagen/métodos , Reproducibilidad de los Resultados , Valor Predictivo de las Pruebas , Adulto Joven
7.
Clin Transl Oncol ; 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38758386

RESUMEN

OBJECTIVE: Treating aggressive superficial squamous cell carcinoma (SCC) poses challenges due to invasiveness. Palliative care is recommended for inoperable cases with extensive tumors near vital organs, risking disfigurement or functional impairment. Electrochemotherapy (ECT) is an emerging cutaneous tumor treatment, but its efficacy against superficial SCC remains uncertain. This study conducts a systematic review and single-arm meta-analysis to evaluate ECT's effectiveness against superficial SCC and provide current evidence for clinical practice. METHODS: Embase, PubMed and Cochrane Library were searched for studies up to May 2023. The random effects model analyzed complete response (CR) and partial response (PR), with subgroup assessment based on drug dosage, treatment response evaluation, tumor size, primary/recurrent status, and tumor location. RESULTS: Ten studies involving 162 patients and 208 tumors were included. Pooled CR and PR rates for ECT-treated superficial SCC were 66.5% (95% CI 48.4%-82.5%; I2 = 84%) and 20.3% (95% CI 10.5%-32.3%; I2 = 70%), respectively. Subgroup analysis indicated ECT's superiority in treating primary tumors (PR: 70%, CR: 30%) and tumors ≤ 3 cm (PR: 81.3%, CR: 10.1%) compared to recurrent tumors (PR: 56.7%, CR: 36.5%) and tumors > 3 cm (PR: 45.2%, CR: 34.4%). CONCLUSION: This single-arm meta-analysis confirms ECT's efficacy against superficial SCC, especially in primary tumors and those ≤ 3 cm in diameter. The study highlights the impact of tumor location and response evaluation on ECT's benefits, warranting further investigation through additional research.

9.
Taiwan J Obstet Gynecol ; 63(3): 307-311, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38802192

RESUMEN

Trace metals play a vital role in a variety of biological processes, but excessive amounts can be toxic and are receiving increasing attention. Trace metals in the environment are released from natural sources, such as rock weathering, volcanic eruptions, and other human activities, such as industrial emissions, mineral extraction, and vehicle exhaust. Lifestyle, dietary habits and environmental quality are the main sources of human exposure to trace metals, which play an important role in inducing human reproductive infertility. The purpose of this review is to summarize the distribution of various trace metals in oocyte and to identify the trace metals that may cause oocyte used in the design and execution of toxicological studies.


Asunto(s)
Oocitos , Oligoelementos , Humanos , Oocitos/efectos de los fármacos , Oligoelementos/análisis , Oligoelementos/efectos adversos , Femenino , Exposición a Riesgos Ambientales/efectos adversos , Metales Pesados/análisis , Metales/efectos adversos , Metales/análisis
10.
Front Microbiol ; 15: 1393073, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38690368

RESUMEN

Carbon catabolite repression (CCR) is a highly conserved mechanism that regulates carbon source utilization in Streptomyces. CCR has a negative impact on secondary metabolite fermentation, both in industrial and research settings. In this study, CCR was observed in the daunorubicin (DNR)-producing strain Streptomyces coeruleorubidus DM, which was cultivated in high concentration of carbohydrates. Unexpectedly, DM exhibited a high ability for anthraquinone glucuronidation biotransformation under CCR conditions with a maximum bioconversion rate of 95% achieved at pH 6, 30°C for 24 h. The co-utilization of glucose and sucrose resulted in the highest biotransformation rate compared to other carbon source combinations. Three novel anthraquinone glucuronides were obtained, with purpurin-O-glucuronide showing significantly improved water solubility, antioxidant activity, and antibacterial bioactivity. Comparative transcript analysis revealed that glucose and sucrose utilization were significantly upregulated as DM cultivated under CCR condition, which strongly enhance the biosynthetic pathway of the precursors Uridine diphosphate glucuronic acid (UDPGA). Meanwhile, the carbon metabolic flux has significantly enhanced the fatty acid biosynthesis, the exhaust of acetyl coenzyme A may lead to the complete repression of the biosynthesis of DNR, Additionally, the efflux transporter genes were simultaneously downregulated, which may contribute to the anthraquinones intracellular glucuronidation. Overall, our findings demonstrate that utilizing CCR can be a valuable strategy for enhancing the biotransformation efficiency of anthraquinone O-glucuronides by DM. This approach has the potential to improve the bioavailability and therapeutic potential of these compounds, opening up new possibilities for their pharmaceutical applications.

11.
Clin Transl Med ; 14(5): e1675, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38689424

RESUMEN

INTRODUCTION: Intrahepatic cholangiocarcinoma (ICC) is characterized by a dismal prognosis with limited therapeutic alternatives. To explore phosphatase and tension homolog (PTEN) as a biomarker for proteasome inhibition in ICC, we conducted a phase II trial to assess the second-line efficacy of bortezomib in PTEN-deficient advanced ICC patients. METHODS: A total of 130 patients with advanced ICC in our centre were screened by PTEN immunohistochemical staining between 1 July 2017, and 31 December 2021, and 16 patients were ultimately enrolled and treated with single-agent bortezomib 1.3 mg/m2 on days 1, 4, 8 and 11 of a 21-day cycle. The primary endpoint was the objective response rate (ORR) according to Response Evaluation Criteria in Solid Tumors v1.1. RESULTS: The median follow-up was 6.55 months (95% confidence interval [CI]: 0.7-19.9 months). Among the 16 enrolled patients, the ORR was 18.75% (3/16) and the disease control rate was 43.75% (7/16). The median progress-free survival was 2.95 months (95% CI: 2.1-5.1 months) and the median overall survival (mOS) was 7.2 months (95% CI: 0.7-21.6 months) in the intent-to-treat-patients. Treatment-related adverse events of any grade were reported in 16 patients, with thrombopenia being the most common toxicity. Patients with PTEN staining scores of 0 were more likely to benefit from bortezomib than those with staining scores > 0. CONCLUSIONS: Bortezomib yielded an encouraging objective response and a favourable OS as a second-line agent in PTEN-deficient ICC patients. Our findings suggest bortezomib as a promising therapeutic option for patients with PTEN-deficient ICC. HIGHLIGHTS: There is a limited strategy for the second-line option of intrahepatic cholangiocarcinoma (ICC). This investigator-initiated phase 2 study evaluated bortezomib in ICC patients with phosphatase and tension homology deficiency. The overall response rate was 18.75% and the overall survival was 7.2 months in the intent-to-treat cohort. These results justify further developing bortezomib in ICC patients with PTEN deficiency.


Asunto(s)
Neoplasias de los Conductos Biliares , Bortezomib , Colangiocarcinoma , Fosfohidrolasa PTEN , Humanos , Colangiocarcinoma/tratamiento farmacológico , Colangiocarcinoma/genética , Bortezomib/uso terapéutico , Bortezomib/farmacología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Estudios Prospectivos , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , Neoplasias de los Conductos Biliares/tratamiento farmacológico , Neoplasias de los Conductos Biliares/genética , Adulto , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología
12.
Inorg Chem ; 63(21): 10092-10098, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38748447

RESUMEN

Exploring efficient alkaline hydrogen oxidation reaction (HOR) electrocatalysts is of great concern for constructing anion exchange membrane fuel cells (AEMFCs). Herein, d-band center modulated PdCo alloys with ultralow Pd content anchored onto the defective carbon support (abbreviated as PdCo/NC hereafter) are proposed as highly efficient HOR catalyst. The as-prepared catalyst exhibits exceptional HOR performance compared to the Pt/C catalyst, achieving thermodynamically spontaneous and kinetically preferential reactions. Specifically, the resultant PdCo/NC demonstrates a marked enhancement in alkaline HOR performance, with the highest mass and specific activities of 1919.6 mA mgPd-1 and 1.9 mA cm-2, 51.1 and 4.2 times higher than those of benchmark of Pt/C, along with an excellent stability in a chronoamperometry test. In the analysis of in situ Raman spectra, it was discovered that tetrahedrally coordinated H-bonded water molecules were formed during the HOR process. This indicates that the promotion of interfacial water molecule formation and enhancement of HOR activities in PdCo/NC are facilitated by defect engineering and the turning of d-band center in PdCo alloy. The essential knowledge obtained in this study could open up a new direction for modifying the electronic structure of cost-effective HOR catalysts through electronic structure engineering.

13.
Comput Methods Programs Biomed ; 250: 108177, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38648704

RESUMEN

BACKGROUND AND OBJECTIVE: The effective segmentation of esophageal squamous carcinoma lesions in CT scans is significant for auxiliary diagnosis and treatment. However, accurate lesion segmentation is still a challenging task due to the irregular form of the esophagus and small size, the inconsistency of spatio-temporal structure, and low contrast of esophagus and its peripheral tissues in medical images. The objective of this study is to improve the segmentation effect of esophageal squamous cell carcinoma lesions. METHODS: It is critical for a segmentation network to effectively extract 3D discriminative features to distinguish esophageal cancers from some visually closed adjacent esophageal tissues and organs. In this work, an efficient HRU-Net architecture (High-Resolution U-Net) was exploited for esophageal cancer and esophageal carcinoma segmentation in CT slices. Based on the idea of localization first and segmentation later, the HRU-Net locates the esophageal region before segmentation. In addition, an Resolution Fusion Module (RFM) was designed to integrate the information of adjacent resolution feature maps to obtain strong semantic information, as well as preserve the high-resolution features. RESULTS: Compared with the other five typical methods, the devised HRU-Net is capable of generating superior segmentation results. CONCLUSIONS: Our proposed HRU-NET improves the accuracy of segmentation for squamous esophageal cancer. Compared to other models, our model performs the best. The designed method may improve the efficiency of clinical diagnosis of esophageal squamous cell carcinoma lesions.


Asunto(s)
Neoplasias Esofágicas , Redes Neurales de la Computación , Tomografía Computarizada por Rayos X , Humanos , Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/radioterapia , Tomografía Computarizada por Rayos X/métodos , Carcinoma de Células Escamosas de Esófago/diagnóstico por imagen , Carcinoma de Células Escamosas de Esófago/radioterapia , Algoritmos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos
14.
Cell Oncol (Dordr) ; 47(4): 1391-1403, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38607517

RESUMEN

PURPOSE: GPX8, which is found in the endoplasmic reticulum lumen, is a member of the Glutathione Peroxidases (GPXs) family. Its role in hepatocellular carcinoma (HCC) is unknown. METHODS: Immunohistochemical staining was used to detect the protein levels of GPX8 in HCC tissue microarrays. A short hairpin RNA lentivirus was used to knock down GPX8, and the main signaling pathways were investigated using transcriptome sequencing and a phosphorylated kinase array. The sphere formation assays, cloning-formation assays and cell migration assays were used to evaluate the stemness and migration ability of HCC cells. Identifying the GPX8-interacting proteins was accomplished through immunoprecipitation and protein mass spectrometry. RESULTS: The GPX8 protein levels were downregulated in HCC patients. Low expression of GPX8 protein was related to early recurrence and poor prognosis in HCC patients. GPX8 knockdown could enhance the stemness and migration ability of HCC cells. Consistently, Based on transcriptome analysis, multiple signaling pathways that include the PI3K-AKT and signaling pathways that regulate the pluripotency of stem cells, were activated after GPX8 knockdown. The downregulation of GPX8 could increase the expression of the tumor stemness markers KLF4, OCT4, and CD133. The in vivo downregulation of GPX8 could also promote the subcutaneous tumor-forming and migration ability of HCC cells. MK-2206, which is a small-molecule inhibitor of AKT, could reverse the tumor-promoting effects both in vivo and in vitro. We discovered that GPX8 and the 71-kDa heat shock cognate protein (Hsc70) have a direct interaction. The phosphorylation of AKT encouraged the translocation of Hsc70 into the nucleus and the expression of the PI3K p110 subunit, thereby increasing the downregulation of GPX8. CONCLUSION: The findings from this study demonstrate the anticancer activity of GPX8 in HCC by inactivating the Hsc70/AKT pathway. The results suggest a possible therapeutic target for HCC.


Asunto(s)
Carcinoma Hepatocelular , Movimiento Celular , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas , Células Madre Neoplásicas , Transducción de Señal , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Movimiento Celular/genética , Regulación hacia Abajo/genética , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Línea Celular Tumoral , Transducción de Señal/genética , Factor 4 Similar a Kruppel , Masculino , Femenino , Animales , Glutatión Peroxidasa/metabolismo , Glutatión Peroxidasa/genética , Persona de Mediana Edad , Ratones Desnudos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratones , Ratones Endogámicos BALB C
15.
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.

16.
Adv Mater ; 36(24): e2313889, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38536181

RESUMEN

Two-dimensional (2D) Dion-Jacobson (DJ) perovskites typically outperform Ruddlesden-Popper (RP) analogs in terms of photodetection (PD). However, the mechanism behind this enhanced performance remains elusive. Theoretical calculations for elucidating interlayer spacer conformation-induced multiple hydrogen bonds in 2D perovskite are presented, along with the synthesis of DPAPbBr4 (DPB) single crystals (SCs) and their PD properties under X-ray/ultraviolet (UV) excitation. The high-quality DPB SC enhances PD with exceptional photoresponse attributes, including a high on/off ratio (4.89 × 104), high responsivity (2.44 A W⁻1), along with large dynamic linear range (154 dB) and low detection limit (7.1 nW cm⁻2), which are currently the best results among 2D perovskite SC detectors, respectively. Importantly, high-resolution images are obtained under UV illumination with weak light levels. The SC X-ray detector exhibits a high sensitivity of 663 µC Gyair⁻1 cm-2 at 10 V and a detection limit of 1.44 µGyair s⁻1. This study explores 2D DJ perovskites for efficient and innovative optoelectronic applications.

17.
Front Public Health ; 12: 1322333, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38410665

RESUMEN

Objective: This study aimed to analyze the growth patterns of height and foot length (FL) among Chinese children aged 3-18 and examine their associations with puberty development. Methods: A cross-sectional survey was conducted in September 2022 in Beijing. Data were collected through questionnaires and on-site physical examinations. The growth patterns and velocity of height and FL in different age groups were described, and their associations with puberty development were analyzed. Results: From an age perspective, the peak FL growth occurred between 9 and 11 years (boys were 11 years and girls were 9 years), while the peak height growth occurred at 11 ~ 13 years for boys and 9 ~ 11 years for girls. Additionally, boys and girls reached 99.0% of their final FL at the ages of 14 and 13, respectively, while they reached 99.0% of their final height at the ages of 16 and 15, respectively. From the perspective of Tanner stage, the age of peak FL growth in boys coincided with the age of the G2 stage, while in girls it occurred slightly earlier than the mean age of the B2 stage. The peak height growth for both boys and girls occurred between Tanner stages 2 and 3. Conclusion: Boys and girls reach their peak FL growth at 11 and 9 years old, respectively, which were both 2 years earlier than their peak height growth. The peak FL growth occurred around the onset of puberty, while the peak height growth occurred between Tanner stages 2 and 3.


Asunto(s)
Estatura , Pubertad , Masculino , Niño , Femenino , Humanos , Estudios Transversales , China
18.
eNeuro ; 11(3)2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38346901

RESUMEN

Human and animal imaging studies demonstrated that chronic pain profoundly alters the structure and the functionality of several brain regions and even causes mental dysfunctions such as depression and anxiety disorders. In this article, we conducted a multimodal study cross-sectionally and longitudinally, to evaluate how neuropathic pain affects the brain. Using the spared nerve injury (SNI) model which promotes long-lasting mechanical allodynia, results showed that neuropathic pain deeply modified the intrinsic organization of the brain functional network 2 weeks after injury. There are significant changes in the activity of the left thalamus (Th_L) and left olfactory bulb (OB_L) brain regions after SNI, as evidenced by both the blood oxygen level-dependent (BOLD) signal and c-Fos expression. Importantly, these changes were closely related to mechanical pain behavior of rats. However, it is worth noting that after morphine administration for analgesia, only the increased activity in the TH region is reversed, while the decreased activity in the OB region becomes more prominent. Functional connectivity (FC) and c-Fos correlation analysis further showed these two regions of interest (ROIs) exhibit different FC patterns with other brain regions. Our study comprehensively revealed the adaptive changes of brain neural networks induced by nerve injury in both cross-sectional and longitudinal dimensions and emphasized the abnormal activity and FC of Th_L and OB_L in the pathological condition. It provides reliable assistance in exploring the intricate mechanisms of diseases.


Asunto(s)
Neuralgia , Humanos , Ratas , Animales , Ratas Sprague-Dawley , Estudios Transversales , Encéfalo/metabolismo , Hiperalgesia , Modelos Animales de Enfermedad
19.
Inorg Chem ; 63(4): 2138-2147, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38237037

RESUMEN

Expediting the torpid kinetics of the oxygen reduction reaction (ORR) at the cathode with minimal amounts of Pt under acidic conditions plays a significant role in the development of proton exchange membrane fuel cells (PEMFCs). Herein, a novel Pt-N-C system consisting of Pt single atoms and nanoparticles anchored onto the defective carbon nanofibers is proposed as a highly active ORR catalyst (denoted as Pt-N-C). Detailed characterizations together with theoretical simulations illustrate that the strong coupling effect between different Pt sites can enrich the electron density of Pt sites, modify the d-band electronic environments, and optimize the oxygen intermediate adsorption energies, ultimately leading to significantly enhanced ORR performance. Specifically, the as-designed Pt-N-C demonstrates exceptional ORR properties with a high half-wave potential of 0.84 V. Moreover, the mass activity of Pt-N-C reaches 193.8 mA gPt-1 at 0.9 V versus RHE, which is 8-fold greater than that of Pt/C, highlighting the enormously improved electrochemical properties. More impressively, when integrated into a membrane electrode assembly as cathode in an air-fed PEMFC, Pt-N-C achieved a higher maximum power density (655.1 mW cm-2) as compared to Pt/C-based batteries (376.25 mW cm-2), hinting at the practical application of Pt-N-C in PEMFCs.

20.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1022508

RESUMEN

Objective:To investigate the efficacy of mFOLFOX7 regimen systemic chemo-therapy combined with camrelizumab and apatinib for hepatocellular carcinoma (HCC) with Vp4 portal vain tumor thrombus (PVTT).Methods:The single-arm, open, exploratory clinical study was conducted. The clinicopathological data of 15 HCC patients with Vp4 PVTT who were admitted to the Sun Yat-sen Memorial Hospital of Sun Yat-sen University from April 2021 to October 2023 were collected. There were 14 males and 1 female, aged 48(range, 33-67)years. All patients underwent treatment with mFOLFOX7 regimen combined with camrelizumab and apatinib. Observa-tion indicators: (1) clinical efficacy; (2) survival of patients. Measurement data with skewed distribution were represented as M(rang), and count data were described as absolute numbers or percentages. Results:(1) Clinical efficacy. All 15 patients underwent treatment with mFOLFOX7 regimen combined with camrelizumab and apatinib. According to the response evaluation criteria in solid tumors version 1.1, the ratio of objective response, ratio of complete response, ratio of partial response, ratio of disease control, median progression free survival time and median total survival time of the 15 patients were 10/15, 1/15, 9/15, 15/15, not reached and not reached. The median progression free survival time and median total survival time were both >9 months. According to the modified response evaluation criteria in solid tumors, the ratio of objective response, ratio of complete response, ratio of partial response, ratio of disease control, median progression free survival time and median total survival time of the 15 patients were 12/15, 6/15, 6/15, 15/15, not reached and not reached. The median progression free survival time and median total survival time were both >9 months. Of the 15 patients, 7 cases were successfully treated with conversion therapy with the surgical conversion rate as 7/15, and all of them achieved R 0 resection. The other 6 cases were failed in conversion therapy, and there were 2 cases still undergoing conversion therapy. Of the 7 patients with successful conver-sion therapy, 5 cases achieved complete pathological remission, 1 case achieved major pathological remission with 90% of tumor tissue necrosis, and 1 case achieved complete remission through imaging examination, but new liver lesions appeared in multiple locations during further observation which were surgically removed. Results of histopathology examination on the patient confirmed multiple liver metastases. The proportion of treatment-associated adverse reactions in 15 patients was 13/15, with 7/15 having ≥grade 3 adverse reactions, including diarrhea (3/15), neutropenia (2/15), thrombo-cytopenia (2/15), and elevated aspartate aminotransferase (2/15). One patient may experience ≥1 adverse reaction. All patients were improved after symptomatic treatment. (2) Survival of patients. All 15 patients were followed up for 13.0(range, 2.0-31.0)months. During the follow-up period, 3 patients died. One case died of upper gastrointestinal bleeding after achieving partial remission, with a survival time of 7.5 months. One case died of multiple liver metastases of tumor, with tumors accounting for over 70% volume of liver and a survival time of 9.5 months. One case with multiple liver tumors and bilateral lung metastasis died due to disease progression after achieving partial remission, with a survival time of 13.5 months. The postoperative follow-up time for 7 patients undergoing surgical treatment was 14.0(range, 2.0-25.0)months. Of the 7 patients, 1 case experien-ced tumor recurrence 20.0 months after surgery, and 6 cases had no recurrence at last time of the follow-up (3 cases completed treatment and entered follow-up observation). The longest survival time was 31.0 months. Conclusion:The mFOLFOX7 regimen systemic chemotherapy combined with camrelizumab and apatinib for HCC with Vp4 PVTT is safe and feasible.

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