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1.
Sensors (Basel) ; 24(12)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38931601

RESUMEN

Muscles play an indispensable role in human life. Surface electromyography (sEMG), as a non-invasive method, is crucial for monitoring muscle status. It is characterized by its real-time, portable nature and is extensively utilized in sports and rehabilitation sciences. This study proposed a wireless acquisition system based on multi-channel sEMG for objective monitoring of grip force. The system consists of an sEMG acquisition module containing four-channel discrete terminals and a host computer receiver module, using Bluetooth wireless transmission. The system is portable, wearable, low-cost, and easy to operate. Leveraging the system, an experiment for grip force prediction was designed, employing the bald eagle search (BES) algorithm to enhance the Random Forest (RF) algorithm. This approach established a grip force prediction model based on dual-channel sEMG signals. As tested, the performance of acquisition terminal proceeded as follows: the gain was up to 1125 times, and the common mode rejection ratio (CMRR) remained high in the sEMG signal band range (96.94 dB (100 Hz), 84.12 dB (500 Hz)), while the performance of the grip force prediction algorithm had an R2 of 0.9215, an MAE of 1.0637, and an MSE of 1.7479. The proposed system demonstrates excellent performance in real-time signal acquisition and grip force prediction, proving to be an effective muscle status monitoring tool for rehabilitation, training, disease condition surveillance and scientific fitness applications.


Asunto(s)
Algoritmos , Electromiografía , Fuerza de la Mano , Electromiografía/métodos , Humanos , Fuerza de la Mano/fisiología , Masculino , Procesamiento de Señales Asistido por Computador , Adulto , Dispositivos Electrónicos Vestibles , Músculo Esquelético/fisiología , Monitoreo Fisiológico/métodos , Monitoreo Fisiológico/instrumentación , Tecnología Inalámbrica/instrumentación
2.
J Appl Clin Med Phys ; 23(11): e13748, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35946900

RESUMEN

To define and evaluate the appropriate abdominal region of interest (ROI) as a surrogate of diaphragm positioning in deep-inspiration breath-hold (DIBH) for surface-guided radiotherapy (SGRT) of abdominal cancers using 3D optical surface imaging (OSI). Six potential abdominal ROIs were evaluated to calculate their correlations with the diaphragm position using 4DCT images of 20 abdominal patients. Twelve points of interest (POIs) were defined (six on the central soft tissue and six on the bilateral ribs) at three superior-inferior levels, and different sub-groups represented different ROIs. ROI-1 was the largest, containing all 12 POIs from the xiphoid to the umbilicus and between the lateral body midlines while ROI-2 had only eight inferior POIs, ROI-3 had six lateral POIs, and ROI-4 had four superior-lateral POIs over the ribs, ROI-5 contained six central and two most inferior-lateral POIs and ROI-6 contained six central and four inferior-lateral POIs. Internally, the right diaphragm dome was used to represent its positions in 4DCT (0% and 50% within the cycle). The Pearson correlation coefficients were calculated between the diaphragm dome and all 12 external POIs individually or grouped as six ROIs. The quality of the abdominal ROIs was evaluated as potential internal surrogates and, therefore, potential ROIs for SGRT DIBH setup. The four most inferior POIs show the highest mean correlation (r = 0.75) with diaphragmatic motion, and the correlation decreases as POIs move superiorly. The mean correlations are the highest for ROIs with little or no rib support: r = 0.67 for ROI-2, r = 0.64 for ROI-5, and r = 0.63 for ROI-6, while lower for ROIs with rib support: ROI-1 has r = 0.60, ROI-3 has r = 0.50, and ROI-4 has only r = 0.28. This study demonstrates that the rectangular/triangular soft-tissue ROI (with little rib support) is an optimal surrogate for body positioning and diaphragmatic motion, even when treating tumors under the rib cage. This evidence-based ROI definition should be utilized when treating abdominal cancers with free-breathing (FB) and/or DIBH setup.


Asunto(s)
Braquiterapia , Neoplasias , Humanos , Contencion de la Respiración , Planificación de la Radioterapia Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Braquiterapia/métodos , Respiración , Dosificación Radioterapéutica
3.
Adv Radiat Oncol ; 8(3): 101183, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36896216

RESUMEN

Purpose: Skin tattoos represent the standard approach for surface alignment and setup of breast cancer radiation therapy, yet permanent skin markings contribute to adverse cosmesis and patient dissatisfaction. With the advent of contemporary surface-imaging technology, we evaluated setup accuracy and timing between "tattoo-less" and traditional tattoo-based setup techniques. Methods and Materials: Patients receiving accelerated partial breast irradiation (APBI) underwent traditional tattoo-based setup (TTB), alternating daily with a tattoo-less setup via surface imaging using AlignRT (ART). Following initial setup, position was verified via daily kV imaging, with matching on surgical clips representing ground truth. Translational shifts (TS) and rotational shifts (RS) were ascertained, as were setup time and total in-room time. Statistical analyses used the Wilcoxon signed rank test and Pitman-Morgan variance test. Results: A total of 43 patients receiving APBI and 356 treatment fractions were analyzed (174 TTB fractions and 182 using ART). For tattoo-less setup via ART, the median absolute TS were 0.31 cm in the vertical (range, 0.08-0.82), 0.23 cm in the lateral (0.05-0.86), and 0.26 cm in the longitudinal (0.02-0.72) axes. For TTB setup, the corresponding median TS were 0.34 cm (0.05-1.98), 0.31 cm (0.09-1.84), and 0.34 cm (0.08-1.25), respectively. The median magnitude shifts were 0.59 (0.30-1.31) for ART and 0.80 (0.27-2.13) for TTB. ART was not statistically distinguishable from TTB in terms of TS, except in the longitudinal direction (P = .154, .059, and .021, respectively), and was superior to TTB for magnitude shift (P < .001). The variance of each TS variable was significantly narrower for ART compared with TTB (P ≤ .001 vertical, P = .001 lateral, P = .005 longitudinal). The median absolute RS for ART was 0.64° rotation (range, 0.00-1.90), 0.65° roll (0.05-2.90), and 0.30° pitch (0.00-1.50). The corresponding median RS for TTB were 0.80° (0.00-2.50), 0.64° (0.00-3.00), and 0.46° (0.00-2.90), respectively. ART setup was not statistically different from TTB in terms of RS (P = .868, .236, and .079, respectively). ART showed lower variance than TTB in terms of pitch (P = .009). The median total in-room time was shorter for ART than TTB (15.42 vs 17.25 minutes; P = .008), as was the median setup time (11.12 vs 13.00 minutes; P = .001). Moreover, ART had a narrower distribution of setup time with fewer lengthy outliers versus TTB. Conclusions: These findings suggest that a tattoo-less setup approach with AlignRT may be sufficiently accurate and expeditious to supplant surface tattoos for patients receiving APBI. Further analyses with larger cohorts will determine whether tattoo-based approaches can be replaced by noninvasive surface imaging.

4.
Front Nutr ; 9: 849811, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35369098

RESUMEN

A long extraction time for traditional cold coffee brewing considerably reduces the production efficiency of this type of beverage. Herein, a new ultrasound-assisted cold brewing (UAC) method was established. The feasibility of UAC was assessed by comparison with main physicochemical characteristics, non-volatile and volatile compounds in coffee extracts produced by hot brewing and conventional static cold brewing methods. Compared to the static cold brews, the levels of total dissolved solids, total lipids, proteins, and titrated acids of UAC coffee extracts increased by 6-26%, 10-21%, 26-31%, and 12-15%, respectively. Caffeine, chlorogenic acid, and trigonelline concentrations were also determined by HPLC. Based on the volatile profiles obtained by HS-SPME-GC/MS, the aroma compounds in UAC was significantly different (p < 0.05) from hot brews but similar to static cold ones, suggesting that ultrasonication compensated for the time of the static cold brewing, thereby considerably shortening the extraction time (1 h vs. 12 h). This work demonstrated that the combination of ultrasound-assisted with cold brew could produce coffee with good flavor and increase the extraction efficiency, which may provide an option for the acceleration of the cold brew coffee process.

5.
Carbohydr Polym ; 266: 118132, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-34044948

RESUMEN

Chitooligosaccharides (COS) are the degraded products of chitin or chitosan. COS is water-soluble, non-cytotoxic to organisms, readily absorbed through the intestine, and eliminated primarily through the kidneys. COS possess a wide range of biological activities, including immunomodulation, cholesterol-lowering, and antitumor activity. Although work on COS goes back at least forty years, several aspects remain unclear. This review narrates the recent developments in COS antitumor activities, while paying considerable attention to the impacts of physicochemical properties (such as molecular weight and degrees of deacetylation) and chemical modifications both in vitro and in vivo. COS derivatives not only improve some physicochemical properties, but also expand the range of applications in drug and gene delivery. COS (itself or as a drug carrier) can inhibit tumor cell proliferation and metastasis, which might be attributed to its ability to stimulate the immune response along with its anti-angiogenic activity. Further, an attempt has been made to report limitations and future research. The potential health benefits of COS and its derivatives against cancer may offer a new insight on their applications in food and medical fields.


Asunto(s)
Antineoplásicos/uso terapéutico , Quitina/análogos & derivados , Neoplasias/tratamiento farmacológico , Animales , Antineoplásicos/síntesis química , Antineoplásicos/farmacocinética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Quitina/farmacocinética , Quitina/uso terapéutico , Quitosano , Humanos , Metástasis de la Neoplasia/tratamiento farmacológico , Oligosacáridos
6.
Nat Biomed Eng ; 4(7): 704-716, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32231314

RESUMEN

Strategies for selectively imaging and delivering drugs to tumours typically leverage differentially upregulated surface molecules on cancer cells. Here, we show that intravenously injected carbon quantum dots, functionalized with multiple paired α-carboxyl and amino groups that bind to the large neutral amino acid transporter 1 (which is expressed in most tumours), selectively accumulate in human tumour xenografts in mice and in an orthotopic mouse model of human glioma. The functionalized quantum dots, which structurally mimic large amino acids and can be loaded with aromatic drugs through π-π stacking interactions, enabled-in the absence of detectable toxicity-near-infrared fluorescence and photoacoustic imaging of the tumours and a reduction in tumour burden after the targeted delivery of chemotherapeutics to the tumours. The versatility of functionalization and high tumour selectivity of the quantum dots make them broadly suitable for tumour-specific imaging and drug delivery.


Asunto(s)
Aminoácidos/química , Carbono/química , Sistemas de Liberación de Medicamentos/métodos , Puntos Cuánticos/química , Nanomedicina Teranóstica/métodos , Animales , Ingeniería Biomédica , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/tratamiento farmacológico , Línea Celular Tumoral , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos
7.
J Agric Food Chem ; 67(6): 1691-1701, 2019 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-30658530

RESUMEN

In recent years, various studies have confirmed the role of natural products as effective cancer prevention and treatment drugs. The present study demonstrated that chitosan oligosaccharide (COS) from shells of shrimp and crab caused an inhibitory effect on the proliferation of human renal carcinoma in vitro and in vivo. First, the in vivo biodistribution of COS was investigated by the synthesis of cyanine-7-labeled COS (COS-Cy7) following tail vein injection. The kidney was found to be a major target organ. Then, the impacts on renal carcinoma cell proliferation, apoptosis, and reactive oxygen species (ROS) production were observed in vitro, and an orthotopic xenograft tumor model was designed to evaluate the antitumor efficacy of COS in vivo. In renal carcinoma cells, COS induced G2/M phase arrest and apoptosis in a ROS-dependent fashion. COS significantly promoted mRNA expression of nuclear factor erythroid 2-related factor (Nrf2) and Nrf2 target genes, such as heme oxygenase 1, modifier subunit of glutamate cysteine ligase, and solute carrier family 7 member 11. Additionally, COS significantly upregulated the protein expression of glucose-regulated protein 78, protein RNA-like endoplasmic reticulum (ER) kinase, eukaryotic initiation factor 2α, activating transcription factor 4, C/EBP homologous protein, and cytochrome c, which justified the activation of the ER stress signaling pathway. In vivo, COS repressed tumor growth and induced apoptosis and ROS accumulation, consistent with the in vitro results. Taken together, COS repressed human renal carcinoma growth and induced apoptosis both in vitro and in vivo, mainly via ROS-dependent ER stress pathways.


Asunto(s)
Carcinoma de Células Renales/tratamiento farmacológico , Quitosano/administración & dosificación , Estrés del Retículo Endoplásmico/efectos de los fármacos , Neoplasias Renales/tratamiento farmacológico , Oligosacáridos/administración & dosificación , Especies Reactivas de Oxígeno/metabolismo , Animales , Apoptosis/efectos de los fármacos , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/fisiopatología , Línea Celular Tumoral , Femenino , Humanos , Neoplasias Renales/genética , Neoplasias Renales/metabolismo , Neoplasias Renales/fisiopatología , Ratones Desnudos , Factor 2 Relacionado con NF-E2 , Factor de Transcripción CHOP
8.
Chem Biol Interact ; 279: 129-135, 2018 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-29155028

RESUMEN

Colon cancer is the third most common cancer, and yet there is a lack of effective therapeutic method with low side effects. Chitosan oligosaccharides (COS) is derived from chitosan after chitin deacetylation, and attracts more interests due to smaller molecular weight and soluble property. Previously, COS, mainly absorbed through intestinal epithelia, has been reported to exhibit many bioactivities, especially its anti-tumor effect. Recent references pay little attention to molecular weight distribution which is crucial for understanding its biological behavior. Here, we studied reducing sugar content and degree of polymerization (DP) of COS. 86.73% reducing sugar exists in COS sample and the content of chitosan fractions with 2-6 is 85.8%. COS suppressed the growth of HCT116 cells in vitro and in vivo, and the inhibition rate of tumor weight in vivo was high up to 58.6%. Moreover, the morphology observation, flow cytometry analysis and mRNA expression were applied to study the apoptosis related mechanism. COS treatment promoted mitosis, late stage apoptosis and S cell cycle arrest in HCT116 cells, and enhanced the mRNA expression of BAK and reduce BCL-2 and BCL-xL. These findings may provide an important clue for clinical applications of COS as anti-tumor drug or pharmaceutic adjuvant in the future.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Quitosano/análogos & derivados , Neoplasias del Colon/tratamiento farmacológico , Oligosacáridos/farmacología , Animales , Antineoplásicos/química , Quitosano/química , Quitosano/farmacología , Relación Dosis-Respuesta a Droga , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HCT116 , Humanos , Ratones , Ratones Desnudos , Oligosacáridos/química
9.
J Food Sci ; 83(2): 535-542, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29350748

RESUMEN

Chitosan oligosaccharides (COS), hydrolyzed products of chitosan, was found to display various biological activities. Herein, we assessed the immunostimulatory activity of COS both in in vitro and in vivo studies. In vitro cytotoxicity studies to murine macrophage RAW264.7 revealed that COS is safe even at the maximum tested concentration of 1000 µg/mL. It also stimulates the production of nitric oxide (NO) and tumor necrosis factor (TNF-α) and enhances the phagocytosis in COS-stimulated RAW264.7. We have shown that the COS could significantly (P < 0.05) restore the reduced immune organs indices, phagocytic index, lymphocyte proliferation, natural killer cell activity, and antioxidant enzyme activities in a cyclophosphamide-induced immunosuppressed mice model. COS can also improve the survival rate in irradiation injury mice and significantly (P < 0.05) increased the spleen indices and up-regulates the CD4+/CD8+ ratio in splenocytes. In sum, the aforementioned results suggest that COS might has the potential to be used as an immunostimulatory agent in patients with immune dysfunctions or be a model for functional food development. PRACTICAL APPLICATION: COS might has the potential to be used as an immunostimulatory agent in patients with immune dysfunctions or be a model for functional food development.


Asunto(s)
Quitosano/administración & dosificación , Ciclofosfamida/efectos adversos , Factores Inmunológicos/administración & dosificación , Oligosacáridos/administración & dosificación , Protectores contra Radiación/administración & dosificación , Animales , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Proliferación Celular/efectos de los fármacos , Femenino , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Ratones , Óxido Nítrico/inmunología , Óxido Nítrico Sintasa de Tipo II/inmunología , Oligosacáridos/farmacología , Fagocitosis/efectos de los fármacos , Factor de Necrosis Tumoral alfa/inmunología
10.
Life Sci ; 202: 21-27, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29626528

RESUMEN

Chitosan oligosaccharides (COS), hydrolyzed products of chitosan, have recently been reported to have various biological activities. Herein, the present study was undertaken to assess the ability of COS to potentiate the antitumor effect of cyclophosphamide (CTX) as well as alleviating the CTX-associated toxicities in vivo, in a residual-tumor; a model which is closer to clinical surgery. Sarcoma 180 (S180) residual-tumor mice were divided into 6 groups (n = 6); including control, CTX, COS 40 mg/kg, COS 80 mg/kg, and combination groups (CTX + COS 40, CTX + COS 80). Animals were killed 18 days post-intraperitoneal administration and the tumors were weighed. The spleens were harvested to determine lymphocytes proliferation and NK cell activities; blood cells were evaluated by flow cytometry, and the expression levels of TNF-α were measured using ELISA. Notably, the combined therapy (CTX + COS80) showed the most effective reduction of the tumor weight, the highest inhibition of tumor growth, and proliferation, when compared with control as well single CTX group. Additionally, COS was able to recover the CTX-induced decreases in the lymphocyte proliferation, splenocyte NK cell activity, TNF-α concentration, and abnormal CD4+/CD8+ T lymphocyte subset. The increase in infiltrating T cells and macrophages best explain the immunostimulatory effect of COS. Results herein highlighted the therapeutic potential of COS as adjuvant treatment during tumor chemotherapy.


Asunto(s)
Antineoplásicos Alquilantes/farmacología , Quitosano/farmacología , Ciclofosfamida/farmacología , Oligosacáridos/farmacología , Sarcoma 180/tratamiento farmacológico , Animales , Proliferación Celular/efectos de los fármacos , Sinergismo Farmacológico , Femenino , Inyecciones Intraperitoneales , Células Asesinas Naturales/efectos de los fármacos , Ratones , Sarcoma 180/patología , Bazo/citología , Bazo/efectos de los fármacos , Subgrupos de Linfocitos T/efectos de los fármacos , Factor de Necrosis Tumoral alfa/biosíntesis
11.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1081-1082: 33-40, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29501027

RESUMEN

A new 3­aminophenylboronic acid-functionalized stationary phase based on silica for hydrophilic interaction liquid chromatography (HILIC) was developed and showed great HILIC characteristics on separation for chito­oligosaccharides. The material was synthesized by grafting 3­aminophenylboronic acid group to silica, and it was characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), elemental analysis and thermal gravimetric analysis (TGA). Nucleobases and nucleosides were used to evaluate the retention property and to investigate retention mechanism by the models designed for description of partitioning and surface adsorption through adjusting ratio of water in the mobile phase. Parameters affecting chromatography behavior such as ionic strength, buffer pH and column temperature were also investigated. Results have indicated that the retention mechanism was a combination of partitioning and surface adsorption, and the hydrogen bond seemed to be the main force for the retention behavior. Finally, the new 3­aminophenylboronic acid-functionalized based on silica stationary phase was applied to separate chito-oligosaccharide samples with optimized mobile phase conditions and showed acceptable chromatograms.


Asunto(s)
Quitina/aislamiento & purificación , Cromatografía Liquida/métodos , Oligosacáridos/aislamiento & purificación , Ácidos Borónicos , Quitina/análisis , Quitina/química , Interacciones Hidrofóbicas e Hidrofílicas , Oligosacáridos/análisis , Oligosacáridos/química , Dióxido de Silicio , Termodinámica
12.
Environ Toxicol Chem ; 36(8): 1991-1997, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28106279

RESUMEN

A rapid monitoring platform for sensitive voltammetric detection of thiamethoxam residues is reported in the present study. A ß-cyclodextrin-reduced graphene oxide composite was used as a reinforcing material in electrochemical determination of thiamethoxam. Compared with bare glassy carbon electrodes, the reduction peak currents of thiamethoxam at reduced graphene oxide/glassy carbon electrode and ß-cyclodextrin-reduced graphene oxide/glassy carbon electrode were increased by 70- and 124-fold, respectively. The experimental conditions influencing voltammetric determination of thiamethoxam, such as the amount of ß-cyclodextrin-reduced graphene oxide, solution pH, temperature, and accumulation time, were optimized. The reduction mechanism and binding affinity of this material is also discussed. Under optimal conditions, the reduction peak currents increased linearly between 0.5 µM and 16 µM concentration of thiamethoxam. The limit of detection was 0.27 µM on the basis of a signal-to-noise ratio of 3. When the proposed method was applied to brown rice in a recovery test, the recoveries were between 92.20% and 113.75%. The results were in good concordance with the high-performance liquid chromatography method. The proposed method therefore provides a promising and effective platform for sensitive and rapid determination of thiamethoxam. Environ Toxicol Chem 2017;36:1991-1997. © 2017 SETAC.


Asunto(s)
Técnicas Electroquímicas/métodos , Monitoreo del Ambiente/métodos , Grafito/química , Nitrocompuestos/análisis , Oxazinas/análisis , Residuos de Plaguicidas/análisis , Tiazoles/análisis , beta-Ciclodextrinas/química , Carbono/química , Técnicas Electroquímicas/instrumentación , Electrodos , Monitoreo del Ambiente/instrumentación , Límite de Detección , Neonicotinoides , Oryza/química , Óxidos/química , Sensibilidad y Especificidad , Relación Señal-Ruido , Tiametoxam
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