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1.
Proc Natl Acad Sci U S A ; 121(22): e2402135121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38771869

RESUMO

Seamless integration of microstructures and circuits on three-dimensional (3D) complex surfaces is of significance and is catalyzing the emergence of many innovative 3D curvy electronic devices. However, patterning fine features on arbitrary 3D targets remains challenging. Here, we propose a facile charge-driven electrohydrodynamic 3D microprinting technique that allows micron- and even submicron-scale patterning of functional inks on a couple of 3D-shaped dielectrics via an atmospheric-pressure cold plasma jet. Relying on the transient charging of exposed sites arising from the weakly ionized gas jet, the specified charge is programmably deposited onto the surface as a virtual electrode with spatial and time spans of ~mm in diameter and ~µs in duration to generate a localized electric field accordantly. Therefore, inks with a wide range of viscosities can be directly drawn out from micro-orifices and deposited on both two-dimensional (2D) planar and 3D curved surfaces with a curvature radius down to ~1 mm and even on the inner wall of narrow cavities via localized electrostatic attraction, exhibiting a printing resolution of ~450 nm. In addition, several conformal electronic devices were successfully printed on 3D dielectric objects. Self-aligned 3D microprinting, with stacking layers up to 1400, is also achieved due to the electrified surfaces. This microplasma-induced printing technique exhibits great advantages such as ultrahigh resolution, excellent compatibility of inks and substrates, antigravity droplet dispersion, and omnidirectional printing on 3D freeform surfaces. It could provide a promising solution for intimately fabricating electronic devices on arbitrary 3D surfaces.

2.
Arch Med Sci ; 20(1): 255-266, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38414448

RESUMO

Introduction: To explore the relationship between the tertiary lymphoid structures (TLSs) and tumor-infiltrating lymphocytes (TILs), and their distribution characteristics as well as the prognostic value in gastric cancer (GC). Material and methods: The TLSs and four subtypes of TILs were assessed by immunohistochemical (IHC) staining. The presence of MECA-79 positive high endothelial venules (HEVs) identified among the ectopic lymphocyte aggregation area in the GC tissue was defined as valid TLSs. The number of labeled TILs was observed in 5 fields of the most positive cells in the tumor center, invasive edge and within the TLSs, at a field of vision ×40. Results: The TLS distribution was significantly higher in the tumor invasive edge than the tumor center (p < 0.001). Similarly, the infiltrating density of CD8+ T cells and GrB+ T cells was statistically significantly higher in the tumor infiltrating edge than the tumor center. The total number of TILs and FOXP3+ T cells showed a contrary distribution. There was a positive correlation of the density of TLSs and TILs with both the location and the immune phenotype. A higher frequency of TILs and TLSs is often associated with favorable clinicopathologic parameters. Higher numbers of peri-TLSs (p = 0.007), peri-CD8+ (p = 0.019) and peri-GrB+TILs (p = 0.032) were significantly correlated with the favorable overall survival. Multivariate analysis revealed that the densities of TILs (p = 0.019) and TLSs (p = 0.037) were independent prognostic predictor for GC patients. Conclusions: We provide evidence that TLSs were positively associated with lymphocyte infiltration in GC. Thus, the formation of TLSs predicts advantageous immune system function and can be considered as a novel biomarker to stratify the overall survival risk of untreated GC patients.

3.
J Mech Behav Biomed Mater ; 151: 106387, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246092

RESUMO

Comprehensive characterization of the transversely isotropic mechanical properties of long bones along both the longitudinal and circumferential gradients is crucial for developing accurate mathematical models and studying bone biomechanics. In addition, mechanical testing to derive elastic, plastic, and failure properties of bones is essential for modeling plastic deformation and failure of bones. To achieve these, we machined a total of 336 cortical specimens, including 168 transverse and 168 longitudinal specimens, from four different quadrants of seven different sections of 3 bovine femurs. We conducted three-point bending tests of these specimens at a loading rate of 0.02 mm/s. Young's modulus, yield stress, tangential modulus, and effective plastic strain for each specimen were derived from correction equations based on classical beam theory. Our statistical analysis reveals that the longitudinal gradient has a significant effect on the Young's modulus, yield stress, and tangential modulus of both longitudinal and transverse specimens, whereas the circumferential gradient significantly influences the Young's modulus, yield stress, and tangential modulus of transverse specimens only. The differences in Young's modulus and yield stress between longitudinal specimens from different sections are greater than 40%, whereas those between transverse specimens are approximately 30%. The Young's modulus and yield stress of transverse specimens in the anterior quadrant were 18.81%/15.46% and 18.34%/14.88% higher than those in the posterior and lateral quadrants, respectively. There is no significant interaction between the longitudinal gradient and the circumferential gradient. Considering the transverse isotropy, it is crucial to consider loading direction when investigating the impact of circumferential gradients in the anterior, lateral, medial, and posterior directions. Our findings indicate that the conventional assumption of homogeneity in simulating the cortical bone of long bones may have limitations, and researchers should consider the anatomical position and loading direction of femur specimens for precise prediction of mechanical responses.


Assuntos
Osso e Ossos , Osso Cortical , Animais , Bovinos , Estresse Mecânico , Módulo de Elasticidade/fisiologia , Fêmur/fisiologia , Fenômenos Biomecânicos
4.
Adv Sci (Weinh) ; 10(34): e2304044, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37870220

RESUMO

Ulcerative colitis is a chronic disease that increases the risk of developing colorectal cancer. Conventional medications are limited by drug delivery and a weak capacity to modulate the inflammatory microenvironment. Further, gut microbiota dysbiosis caused by mucosal damage and dysregulated redox homeostasis leads to frequent recurrence. Therefore, promoting mucosal healing and restoring redox homeostasis is considered the initial step in treating ulcerative colitis. Plasma-activated solutions (PAS) are liquids rich in various reactive nitrogen species (RNS) and reactive oxygen species (ROS) and are used to treat multiple diseases. However, its effect on ulcerative colitis remains to be examined. Therefore, using a DSS-induced mice colitis model, it is found that PAS has the potential to treat colitis and prevent its recurrence by promoting intestinal mucosal repair, reducing inflammation, improving redox homeostasis, and reversing gut microbiota dysbiosis. Further, an equipment is designed for preparing PAS without using nitrogen; however, after treatment with the Nitro-free PAS, the therapeutic effect of PAS is significantly weakened or even lost, indicating that RNS may be the main mediator by which PAS exerts its therapeutic effects. Overall, this study demonstrates the treatment of ulcerative colitis as a novel application of PAS.


Assuntos
Colite Ulcerativa , Colite , Microbiota , Animais , Camundongos , Colite Ulcerativa/induzido quimicamente , Disbiose/induzido quimicamente , Colite/induzido quimicamente , Modelos Animais de Doenças , Homeostase , Oxirredução
5.
Rev Sci Instrum ; 94(10)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37796096

RESUMO

Moisture ingress is one of the major causes of aging in oil-paper insulated transformers; the measurement of the moisture content of the insulating material is thus necessary during transformer disassembly for maintenance. One critical engineering consideration is the need for rapid and nondestructive moisture content measurement of the oil-paper insulation to minimize the power-outage time. Herein, a rapid characterization method for the moisture content of oil-paper insulation based on the dielectric response obtained using a microstrip petal-like ring resonator (MPRR) is proposed. The geometric parameters of the resonator and dielectric response model were established based on simulations and theoretical analysis. The geometry of the resonant ring was optimized by modifying the originally circular ring structure of the microstrip ring resonator (MRR) into a petal-like ring structure; this increases the number of resonant peaks from five to seven in the frequency range of 0.5-6.0 GHz for the same electrode area. The effects of the coupling mode, coupling gap, and microstrip ring size on the resonance characteristics of the MPRR were simulated and analyzed. Compared with the MRR, the MPRR has the advantages of a reduced fundamental resonant frequency and a smaller resonant-ring area that improves radiation efficiency. The impact of moisture content on the dielectric response of the pressboard obtained using the MPRR was studied. A moisture-calculation equation based on the measured dielectric response for a selected type of pressboard was established by the Lasso regression. The results of verification experiments show that the error of the proposed method is sufficient for practical applications.

6.
ACS Appl Mater Interfaces ; 15(34): 40963-40974, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37599413

RESUMO

High-voltage and high-power devices are indispensable in spacecraft for outer space explorations, whose operations require aerospace materials with adequate vacuum surface insulation performance. Despite persistent attempts to fabricate such materials, current efforts are restricted to trial-and-error methods and a universal design guideline is missing. The present work proposes to improve the vacuum surface insulation by tailoring the surface trap state density and energy level of the metal oxides with varied bandgaps, using coating on a polyimide (PI) substrate, aiming for a more systematical workflow for the insulation material design. First-principle calculations and trap diagnostics are employed to evaluate the material properties and reveal the interplay between trap states and the flashover threshold, supported by dedicated analyses of the flashover voltage, secondary electron emission (SEE) from insulators, and surface charging behaviors. Experimental results suggest that the coated PI (i.e., CuO@PI, SrO@PI, MgO@PI, and Al2O3@PI) can effectively increase the trap density and alter the trap energy levels. Elevated trap density is demonstrated to always yield lower SEE. In addition, increasing shallow trap density accelerates surface charge dissipation, which is favorable for improving surface insulation. CuO@PI exhibits the most remarkable increase in shallow trap density, and accordingly, the highest flashover voltage is 42.5% higher than that of pristine PI. This study reveals the critical role played by surface trap states in flashover mitigation and offers a novel strategy to optimize the surface insulation of materials.

7.
Polymers (Basel) ; 15(15)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37571104

RESUMO

High-temperature vulcanized silicone rubber (HTV-SR) employed for composite insulators is continuously subjected to a complex environment of alternating heat, corona discharge, humidity, etc. These stresses (especially alternating heat) complicate the aging mechanism of HTV-SR, which lacks systematic investigation. In this paper, a multi-factor aging platform considering temperature cycling, moisture, and corona discharge is established. Specifically, four temperature-cycling settings are employed, each of which lasts for 15 cycles. The surface morphology, hydrophobicity, and chemical, mechanical, and electrical properties of aged samples are methodically characterized. Experimental results show that the aging degree is correlated to the range of temperature cycling, which is attributed to diverse crosslink-degradation degrees with different temperature differences. Under a large temperature difference (70 °C), HTV-SR possesses a high crosslinking degree and a low degradation degree, making the material hard but easy to crack with alternating thermal stress. Then, severe defects and water condensation emerge on the HTV-SR surface, which promote the diffusion of corona products and water molecules into the material. The subsequent rise in crosslinking density caused by in-depth oxidation further exacerbates the aging of the material. Consequently, it brings about poor hydrophobicity, high interfacial polarization, and shallow trap energy levels in HTV-SR. This work provides a detailed analysis of the aging mechanism of HTV-SR in a simulated on-site environment.

8.
Materials (Basel) ; 16(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37512321

RESUMO

With the development of vacuum electronic devices toward high power, high frequency, and miniaturization, the voltage holdoff capacity of the insulation materials in devices has also been raised to a higher demand. Cr/Mn/Ti-doped Al2O3 ceramics were prepared, and the bulk density, micromorphology, phase composition, resistivity, secondary electron emission coefficient, and surface flashover threshold in the vacuum of the Al2O3 were characterized. The results show that the addition of TiO2 to the Al2O3 ceramic can promote the sintering of the ceramic. The Cr/Mn/Ti-doped Al2O3 ceramic with a homogeneous microstructure can be obtained by an appropriate amount of TiO2 addition. In the process of the heat treatment, the TiO2 in the ceramics was reduced to a certain degree, which had an impact on the microstructure of the Al2O3 ceramic. Adding a small amount of TiO2 can improve the voltage holdoff performance in the vacuum. The value of the surface flashover threshold in the vacuum of the Cr/Mn/Ti-doped Al2O3 ceramic containing 1 wt.% TiO2 reached a value of 33 kV, which is 32% higher than that of the basic Al2O3 ceramic. The preparation of Al2O3 ceramics with a high voltage holdoff capacity in a vacuum provides fundamental technical support for the development of vacuum electronic devices.

9.
Cancer Med ; 12(16): 17028-17036, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37458126

RESUMO

BACKGROUND: In the study, we aimed to evaluate the ability of micro-histology combined with cytology to improve the quality of slides and diagnose endometrial lesions. METHODS: Endometrial specimens were collected from Li Brushes. Every specimen was prepared for micro-histological and cytological slides, using cell block (CB) and liquid-based cytology (LBC) technologies. Semi-quantitative scoring system was used to evaluate the qualities of slides. CB slides were assessed by 5-category scoring system. Diagnostic accuracy was calculated in LBC, CB, and LBC + CB groups based on the histological gold standard. Endometrial atypical hyperplasia, and endometrial cancer were considered positive, whereas others were considered negative. RESULTS: A total of 167 patients were enrolled. CB slides were inferior to LBC slides only in cellularity (p < 0.001), but superior in the other six parameters (all p < 0.001). The satisfaction rate of micro-histology accounted for 92.3%. The accuracy index in the CB group was higher than in the LBC group in terms of sensitivity (85.5% vs. 82.7%) and specificity (98.9% vs. 95.7%). The sensitivity and specificity in the LBC + CB group were increased to 94.2% and 99.0%, respectively. CONCLUSIONS: The quality of micro-histological slides was higher than that of cytological slides. By combining micro-histology with cytology, higher accuracy was achieved for endometrial lesions diagnosis.


Assuntos
Citodiagnóstico , Neoplasias do Endométrio , Feminino , Humanos , Endométrio/patologia , Sensibilidade e Especificidade , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/patologia
10.
Micromachines (Basel) ; 14(5)2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37241674

RESUMO

It is of great significance for structural design and engineering evaluation to obtain the elastic-plastic parameters of materials. The inverse estimation of elastic-plastic parameters of materials based on nanoindentation technology has been applied in many pieces of research, but it has proved to be difficult to determine the elastic-plastic properties of materials by only using a single indentation curve. A new optimal inversion strategy based on a spherical indentation curve was proposed to obtain the elastoplastic parameters (the Young's modulus E, yield strength σy, and hardening exponent n) of materials in this study. A high-precision finite element model of indentation with a spherical indenter (radius R = 20 µm) was established, and the relationship between the three parameters and indentation response was analyzed using the design of experiment (DOE) method. The well-posed problem of inverse estimation under different maximum indentation depths (hmax1 = 0.06 R, hmax2 = 0.1 R, hmax3 = 0.2 R, hmax4 = 0.3 R) was explored based on numerical simulations. The results show that the unique solution with high accuracy can be obtained under different maximum press-in depths (the minimum error was within 0.2% and the maximum error was up to 1.5%). Next, the load-depth curves of Q355 were obtained by a cyclic loading nanoindentation experiment, and the elastic-plastic parameters of Q355 were determined by the proposed inverse-estimation strategy based on the average indentation load-depth curve. The results showed that the optimized load-depth curve was in good agreement with the experimental curve, and the optimized stress-strain curve was slightly different from the tensile test, and the obtained parameters were basically consistent with the existing research.

11.
Rev Sci Instrum ; 94(1): 014101, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725542

RESUMO

This study introduces the design principle of a high-frequency square wave power supply, as well as the simulation and design process of a minimally invasive electrosurgical scalpel, which formed the low temperature plasma in saline solution. In order to verify the performance of the device, saline discharge experiments and pork ablation experiments were performed. An alternating high-frequency square-wave voltage was applied between coaxial double-layer electrodes with a spacing of 400 µm. The waveforms and amplitude of output voltage and current, conductance between electrodes, and output power were measured in saline discharge experiments. The results of pork ablation experiments with different power sources demonstrate that the device can generate low-temperature plasma for ablation rather than relying on thermal effects. The device can ablate pork under the driving of a 10 V, 100 kHz square wave voltage. In addition, the ablation speed and area will be greater with an increase in voltage or frequency.

12.
Asian J Urol ; 10(1): 19-26, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36721698

RESUMO

Objective: To assess the concordance of tumour grade in specimens obtained from diagnostic cystoscopic biopsy and transurethral resection of bladder tumour (TURBT) and explore the risk factors of upgrading. Methods: The medical records of 205 outpatients who underwent diagnostic cystoscopic biopsy before initial TURBT were retrospectively reviewed. Comparative analysis of the tumour grade of biopsy and operation specimens was performed. Tumour grade changing from low-grade to high-grade with or without variant histology was defined as upgrading. Logistic regression analyses were performed to identify the risk factors of upgrading. Results: For the 205 patients, the concordance of tumour grade between specimens obtained from biopsy and operation was 0.639. The concordance for patients who were preoperatively diagnosed with low-grade and high-grade was 0.504 and 0.912, respectively. Univariate and multivariate logistic regression analyses showed that older age, tumour multifocality, high neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and low lymphocyte-to-monocyte ratio (LMR) were significantly associated with upgrading (odds ratio ranging from 0.412 to 4.364). The area under the curve of the different multivariate models was improved from 0.752 to 0.821, and decision curve analysis demonstrated a high net benefit when NLR, LMR, and PLR were added. Conclusion: Diagnostic cystoscopic biopsy may not accurately represent the true grade of primary bladder cancer, especially for outpatients with low-grade bladder cancer. Moreover, older age, tumour multifocality, high NLR, PLR, and low LMR are risk factors of upgrading, and systemic inflammatory markers improve the predictive ability.

13.
Cell Rep Med ; 4(2): 100914, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36720223

RESUMO

This study develops a method combining a convolutional neural network model, INSIGHT, with a self-attention model, WiseMSI, to predict microsatellite instability (MSI) based on the tiles in colorectal cancer patients from a multicenter Chinese cohort. After INSIGHT differentiates tumor tiles from normal tissue tiles in a whole slide image, features of tumor tiles are extracted with a ResNet model pre-trained on ImageNet. Attention-based pooling is adopted to aggregate tile-level features into slide-level representation. INSIGHT has an area under the curve (AUC) of 0.985 for tumor patch classification. The Spearman correlation coefficient of tumor cell fraction given by expert pathologist and INSIGHT is 0.7909. WiseMSI achieves a specificity of 94.7% (95% confidence interval [CI] 93.7%-95.7%), a sensitivity of 84.7% (95% CI 82.6%-86.9%), and an AUC of 0.954 (95% CI 0.948-0.960). Comparative analysis shows that this method has better performance than the other five classic deep learning methods.


Assuntos
Neoplasias Colorretais , Instabilidade de Microssatélites , Humanos , Redes Neurais de Computação , Neoplasias Colorretais/patologia
14.
Bioresour Technol ; 369: 128422, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36462768

RESUMO

The impacts of carrier type on anammox community assembly, species interactions and nitrogen conversion were studied in this work. It was found that in addition to shared species with higher abundance, different carrier types recruited rare species by imposing selection pressure. Results from co-occurrence networks revealed that carrier type strongly influenced interactions between keystone species inhabiting within anammox biofilm through potentially inducing niche differences. Overall, elastic cubic sponges would lead to closer cooperation between different populations, whereas plastic hollow cylinders would trigger fiercer competition. Meanwhile, the results based on metagenomics sequencing showed carrier type significantly affected nitrogen conversion related genes abundances, and higher reads number was detected on the elastic cubic sponges. The information obtained in this work could provide some valuable information for the selection and optimization of carrier type in the anammox process.


Assuntos
Oxidação Anaeróbia da Amônia , Nitrogênio , Reatores Biológicos , Oxirredução , Metagenômica , Anaerobiose , Desnitrificação
16.
Front Surg ; 9: 989061, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36303850

RESUMO

Background and aim: The number of elderly patients with biliary stones is increasing. Endoscopic retrograde cholangiography (ERCP) is considered to be an effective treatment for biliary stones. Having a sound knowledge of the risk factors can help reduce the incidence and severity of complications for ERCP. Furthermore, limited research has been published on patients aged over 85 years undergoing endoscopic biliary stone removal. This study aims to determine the risk factors that lead to complications of ERCP in patients over 85 years of age. Methods: This was a single-center retrospective study. We analyzed 156 patients aged ≥ 85 years with biliary stones who underwent their first ERCP at Chinese PLA General Hospital from February 2002 to March 2021. Logistic regression models were employed to identify the independent risk factors for complications. Results: A total of 13 patients (8.3%) had complications. Thereinto, pancreatitis, cholangitis, bleeding, and other complications occurred in 4 cases (2.6%), 1 cases (0.6%), 4 cases (2.6%), and 4 cases (2.6%), respectively. There was no perforation or death related to ERCP. Independent risk factors for complications were acute biliary pancreatitis (ABP) (P = 0.017) and Charlson Comorbidity Index (CCI) (P = 0.019). Significantly, reasons for incomplete stone removal at once were large stone (>10 mm) (P < 0.001) and higher acute physiology and chronic health evaluation scoring system (APACHE-II) (P = 0.005). Conclusions: ERCP was recommended with caution in patients ≥ 85 years of age with ABP or higher CCI undergoing endoscopic biliary stone removal. In patients with ABP without cholangitis or biliary obstruction we recommend against urgent (within 48 h) ERCP. Patients with higher CCI who can tolerate ERCP can undergo rapid ERCP biliary stenting or nasobiliary implantation with later treatment of stones, and patients who cannot tolerate ERCP are treated promptly with PTCD and aggressive conservative treatment.

17.
J Biomech ; 144: 111350, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36288678

RESUMO

Characterizing the mechanical properties of different anatomical quadrants of bones has been conducted in the literature to help understand the correlations among bone morphometric, densitometric, and material properties. However, although there are data to compare four quadrants of the long bones of the adult, there is very limited research on the young adult especially young female. Hence, nine tibia mid-shaft specimens were harvested from nine 8-week-old C57BL/6J female mice, which roughly correspond to the age range of juvenile to young adult, with one left tibia being harvested from one animal. A total of 144 indentation tests were performed with four indentations per quadrant and each of nine tibia specimens being divided into four quadrants. The Oliver and Pharr methods were used to calculate the indentation modulus and hardness. One-way ANOVA and the Kruskal-Wallis nonparametric test were used to study the influence of different anatomical quadrants on the indentation modulus and hardness. The results showed that the indentation modulus of the 8-week-old mouse tibia shaft was 18.94 ± 0.91 GPa, and the hardness was 0.51 ± 0.02 GPa. The influence of circumferential anatomical quadrants on the tibial shaft indentation modulus (p = 0.398) and hardness (p = 0.895) was not statistically significant. These methods and results could potentially help study treatments for young female long bones by comprehensively understanding the effect of treatments on four quadrants, considering collagen fiber, the degree of mineralization, and the changes of collagen cross-linking through high-resolution nanoindentation.


Assuntos
Diáfises , Tíbia , Camundongos , Feminino , Animais , Camundongos Endogâmicos C57BL , Dureza , Colágeno
18.
Front Bioeng Biotechnol ; 10: 920991, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36213062

RESUMO

Background: We aimed to study the mechanism of sacral nerve injury caused by sacral fractures and the relationship between nerve decompression and nerve function. Methods: First, we observed the anatomical features of lumbosacral nerve root region in Sprague-Dawley rats. Next, the rats were divided into the sham, 10 g, 30 g, and 60 g groups for electrophysiological studies on nerve root constriction injury. Then we studied the biomechanical properties of rat nerve roots, lumbosacral trunk, and sacrum. Finally, we established a finite element analysis model of sacral nerve roots injury in rats and determined the correlation between sacral deformation and the degree of sacral nerve roots injury. Result: Anatomical study showed L5 constitutes sciatic nerve, the length of the L5 nerve root is 3.67 ± 0.15 mm, which is suitable for electrophysiological research on nerve root compression injury. After a series of electrophysiological study of L5 nerve roots, our results showed that nerve root function was almost unaffected at a low degree of compression (10 g). Nerve root function loss began at 30 g compression, and was severe at 60 g compression. The degree of neurological loss was therefore positively correlated with the degree of compression. Combining biomechanical testing of the lumbosacral nerve roots, finite element analysis and neuroelectrophysiological research, we concluded when the sacral foramina deformation is >22.94%, the sacral nerves lose function. When the compression exceeds 33.16%, early recovery of nerve function is difficult even after decompression. Conclusion: In this study, we found that the neurological loss was positively correlated with the degree of compression. After early decompression, nerve root function recovery is possible after moderate compression; however, in severe compression group, the nerve function would not recover. Furthermore, FEA was used to simulate nerve compression during sacral fracture, as well as calculate force loading on nerve with different deformation rates. The relationship between sacral fractures and neurological loss can be analyzed in combination with neurophysiological test results.

19.
Front Immunol ; 13: 978715, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36081505

RESUMO

Tumor infiltration pattern (INF) and tumor origin site were reported to significantly affect the prognosis of gastric cancer (GC), while the immune status under these contexts is not clear. In this study, we correlated the density and phenotype of tumor-infiltrating lymphocytes (TILs) with INF and the tumor origin site to reflect the biological behavior of tumors from a new perspective and also determined their effects on overall survival (OS) and other related clinicopathological features in archival samples of 147 gastric cancers with 10-year follow-up data. We found that the INFc growth pattern (an invasive growth without a distinct border) of GC lacked immune cell infiltration, particularly the cytotoxic T cells and their activated form. It is also significantly associated with an unfavorable prognosis (P < 0.001) and proximal site (P = 0.001), positive lymph node metastasis (P = 0.002), and later tumor-node-metastasis stage (P < 0.001). Moreover, the density and sub-type of TILs infiltration were significantly different in disparate differentiated areas for the tumor tissue with INFb. Compared with distal gastric cancer, proximal gastric cancers were prone to grow in an INFc pattern (P = 0.001) and infiltrated with fewer TILs, experiencing a shorter survival time (P = 0.013). Multivariate analysis showed that only the INF and the density of TILs were demonstrated to be the independent prognostic factors of OS for the GC. We concluded that GC with an aggressive growth pattern arising from proximal sites always had a weak immune response and resulted in a poor prognosis. The interaction between them and their synergistic or antagonistic effects in the development of tumors need to be further studied. This study opens up a new perspective for research on the biological behavior of the tumor.


Assuntos
Adenocarcinoma , Neoplasias Gástricas , Adenocarcinoma/patologia , Humanos , Metástase Linfática , Linfócitos do Interstício Tumoral , Prognóstico , Neoplasias Gástricas/patologia
20.
Cancers (Basel) ; 14(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36077646

RESUMO

OBJECTIVES: The soaring demand for endometrial cancer screening has exposed a huge shortage of cytopathologists worldwide. To address this problem, our study set out to establish an artificial intelligence system that automatically recognizes and diagnoses pathological images of endometrial cell clumps (ECCs). METHODS: We used Li Brush to acquire endometrial cells from patients. Liquid-based cytology technology was used to provide slides. The slides were scanned and divided into malignant and benign groups. We proposed two (a U-net segmentation and a DenseNet classification) networks to identify images. Another four classification networks were used for comparison tests. RESULTS: A total of 113 (42 malignant and 71 benign) endometrial samples were collected, and a dataset containing 15,913 images was constructed. A total of 39,000 ECCs patches were obtained by the segmentation network. Then, 26,880 and 11,520 patches were used for training and testing, respectively. On the premise that the training set reached 100%, the testing set gained 93.5% accuracy, 92.2% specificity, and 92.0% sensitivity. The remaining 600 malignant patches were used for verification. CONCLUSIONS: An artificial intelligence system was successfully built to classify malignant and benign ECCs.

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