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1.
Proc Natl Acad Sci U S A ; 119(8)2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35181607

RESUMEN

Interface phonon modes that are generated by several atomic layers at the heterointerface play a major role in the interface thermal conductance for nanoscale high-power devices such as nitride-based high-electron-mobility transistors and light-emitting diodes. Here we measure the local phonon spectra across AlN/Si and AlN/Al interfaces using atomically resolved vibrational electron energy-loss spectroscopy in a scanning transmission electron microscope. At the AlN/Si interface, we observe various interface phonon modes, of which the extended and localized modes act as bridges to connect the bulk AlN modes and bulk Si modes and are expected to boost the phonon transport, thus substantially contributing to interface thermal conductance. In comparison, no such phonon bridge is observed at the AlN/Al interface, for which partially extended modes dominate the interface thermal conductivity. This work provides valuable insights into understanding the interfacial thermal transport in nitride semiconductors and useful guidance for thermal management via interface engineering.

2.
Small ; : e2400516, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38686688

RESUMEN

Chronic wounds constitute an increasingly prevalent global healthcare issue, characterized by recurring bacterial infections, pronounced oxidative stress, compromised functionality of immune cells, unrelenting inflammatory reactions, and deficits in angiogenesis. In response to these multifaceted challenges, the study introduced a stimulus-responsive glycopeptide hydrogel constructed by oxidized Bletilla striata polysaccharide (OBSP), gallic acid-grafted ε-Polylysine (PLY-GA), and paeoniflorin-loaded micelles (MIC@Pae), called OBPG&MP. The hydrogel emulates the structure of glycoprotein fibers of the extracellular matrix (ECM), exhibiting exceptional injectability, self-healing, and biocompatibility. It adapts responsively to the inflammatory microenvironment of chronic wounds, sequentially releasing therapeutic agents to eradicate bacterial infection, neutralize reactive oxygen species (ROS), modulate macrophage polarization, suppress inflammation, and encourage vascular regeneration and ECM remodeling, playing a critical role across the inflammatory, proliferative, and remodeling phases of wound healing. Both in vitro and in vivo studies confirmed the efficacy of OBPG&MP hydrogel in regulating the wound microenvironment and enhancing the regeneration and remodeling of chronic wound skin tissue. This research supports the vast potential for herb-derived multifunctional hydrogels in tissue engineering and regenerative medicine.

3.
Osteoporos Int ; 35(1): 117-128, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37670164

RESUMEN

This study utilized deep learning to classify osteoporosis and predict bone density using opportunistic CT scans and independently tested the models on data from different hospitals and equipment. Results showed high accuracy and strong correlation with QCT results, showing promise for expanding osteoporosis screening and reducing unnecessary radiation and costs. PURPOSE: To explore the feasibility of using deep learning to establish a model for osteoporosis classification and bone density value prediction based on opportunistic CT scans and to verify its generalization and diagnostic ability using an independent test set. METHODS: A total of 1219 cases of opportunistic CT scans were included in this study, with QCT results as the reference standard. The training set: test set: independent test set ratio was 703: 176: 340, and the independent test set data of 340 cases were from 3 different hospitals and 4 different CT scanners. The VB-Net structure automatic segmentation model was used to segment the trabecular bone, and DenseNet was used to establish a three-classification model and bone density value prediction regression model. The performance parameters of the models were calculated and evaluated. RESULTS: The ROC curves showed that the mean AUCs of the three-category classification model for categorizing cases into "normal," "osteopenia," and "osteoporosis" for the training set, test set, and independent test set were 0.999, 0.970, and 0.933, respectively. The F1 score, accuracy, precision, recall, precision, and specificity of the test set were 0.903, 0.909, 0.899, 0.908, and 0.956, respectively, and those of the independent test set were 0.798, 0.815, 0.792, 0.81, and 0.899, respectively. The MAEs of the bone density prediction regression model in the training set, test set, and independent test set were 3.15, 6.303, and 10.257, respectively, and the RMSEs were 4.127, 8.561, and 13.507, respectively. The R-squared values were 0.991, 0.962, and 0.878, respectively. The Pearson correlation coefficients were 0.996, 0.981, and 0.94, respectively, and the p values were all < 0.001. The predicted values and bone density values were highly positively correlated, and there was a significant linear relationship. CONCLUSION: Using deep learning neural networks to process opportunistic CT scan images of the body can accurately predict bone density values and perform bone density three-classification diagnosis, which can reduce the radiation risk, economic consumption, and time consumption brought by specialized bone density measurement, expand the scope of osteoporosis screening, and have broad application prospects.


Asunto(s)
Enfermedades Óseas Metabólicas , Aprendizaje Profundo , Osteoporosis , Humanos , Densidad Ósea , Osteoporosis/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Estudios Retrospectivos
4.
Langmuir ; 39(6): 2301-2311, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36719318

RESUMEN

The potential of spider silk as an intriguing biological prototype for collecting water from a humid environment has attracted wide attention, and various materials with suitable structures have been engineered. Here, inspired by this phenomenon, a kind of superwetting poly(vinylidene fluoride) (PVDF) membrane with spindle-knotted structured fibers was prepared by the electrospinning method followed by oxygen plasma etching treatment. The prepared membrane presented a satisfactory separation efficiency for various oil-in-water emulsions. The cooperative effect of the special wettability property and the spindle-knot structure stimulated the emulsified oil droplets to accumulate quickly on the membrane surface. A model that explains the accumulation of emulsified oil droplets has also been developed. Furthermore, an artificial fiber comprising a micron-sized spindle-knot structure was prepared by the dip-coating method to clearly illustrate the aggregation process of the emulsified oil droplets and to verify the theoretical explanation. We hope that this study will provide new inspiration for oil/water emulsion separation techniques.

5.
Biogerontology ; 24(4): 581-592, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37052773

RESUMEN

There is growing evidence that extracellular vesicles (EVs) play a functional role in tissue repair and anti-aging by transferring the contents of donor cells to recipient cells. We hypothesized that Dauer (C. elegans), known as "ageless" nematodes, can also secrete extracellular vesicles and influence the lifespan of C. elegans. Here, we isolated EVs of dauer larvae (dauer EVs). Dauer EVs were characterized using transmission electron microscopy, nanoparticle tracking analysis (NTA), and Western blot analysis. Wild-type C. elegans were fed in the presence or absence of dauer EVs and tested for a range of phenotypes, including longevity, mobility and reproductive capacity. Results showed that dauer EVs increased the average lifespan of nematodes by 15.74%, improved mobility, slowed age-related pigmentation as well as body length, and reduced the accumulation of reactive oxygen species and lipids, while not impairing nematode reproductive capacity. These findings suggest that dauer EVs can extend the lifespan of C. elegans as well as the healthy lifespan by reducing ROS accumulation, with potential anti-aging capacity.


Asunto(s)
Proteínas de Caenorhabditis elegans , Vesículas Extracelulares , Animales , Caenorhabditis elegans/genética , Larva , Envejecimiento , Proteínas de Caenorhabditis elegans/genética , Longevidad/genética
6.
BMC Med Imaging ; 23(1): 106, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37582697

RESUMEN

BACKGROUND: Biparametric MRI (bpMRI) is a faster, contrast-free, and less expensive MRI protocol that facilitates the detection of prostate cancer. The aim of this study is to determine whether a biparametric MRI PI-RADS v2.1 score-based model could reduce unnecessary biopsies in patients with suspected prostate cancer (PCa). METHODS: The patients who underwent MRI-guided biopsies and systematic biopsies between January 2020 and January 2022 were retrospectively analyzed. The development cohort used to derive the prediction model consisted of 275 patients. Two validation cohorts included 201 patients and 181 patients from 2 independent institutions. Predictive models based on the bpMRI PI-RADS v2.1 score (bpMRI score) and clinical parameters were used to detect clinically significant prostate cancer (csPCa) and compared by analyzing the area under the curve (AUC) and decision curves. Spearman correlation analysis was utilized to determine the relationship between International Society of Urological Pathology (ISUP) grade and clinical parameters/bpMRI score. RESULTS: Logistic regression models were constructed using data from the development cohort to generate nomograms. By applying the models to the all cohorts, the AUC for csPCa was significantly higher for the bpMRI PI-RADS v2.1 score-based model than for the clinical model in both cohorts (p < 0.001). Considering the test trade-offs, urologists would agree to perform 10 fewer bpMRIs to avoid one unnecessary biopsy, with a risk threshold of 10-20% in practice. Correlation analysis showed a strong correlation between the bpMRI score and ISUP grade. CONCLUSION: A predictive model based on the bpMRI score and clinical parameters significantly improved csPCa risk stratification, and the bpMRI score can be used to determine the aggressiveness of PCa prior to biopsy.


Asunto(s)
Imagen por Resonancia Magnética , Neoplasias de la Próstata , Masculino , Humanos , Imagen por Resonancia Magnética/métodos , Próstata/diagnóstico por imagen , Próstata/patología , Nomogramas , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Antígeno Prostático Específico , Estudios Retrospectivos , Biopsia Guiada por Imagen/métodos
7.
Anal Chem ; 94(8): 3467-3475, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35171581

RESUMEN

Accurate full-length sequencing of a purified unknown protein is still challenging nowadays due to the error-prone mass-spectrometry (MS)-based methods. De novo identified peptide sequence largely contain errors, undermining the accuracy of assembly. Bias on the detectability of the peptides also makes low-coverage regions, resulting in gaps. Although recent advances on multi-enzyme hydrolysis and algorithms showed complete assembly of full-length protein sequences in a few examples, the robustness in practical application is still to be improved. Here, inspired by genome assembly strategies, we demonstrate a contig-scaffolding strategy to assemble protein sequences with high robustness and accuracy. This strategy integrates multiple unspecific hydrolysis methods to minimize the bias in the hydrolysis process. After de novo identification of the peptides, our assembly algorithm, named Multiple Contigs & Scaffolding (MuCS), assembles the peptide sequences in a multistep, i.e., contig-scaffold manner, with error correction in each step. MS data from different hydrolysis experiments complement each other for robust contig extension and error correction. We demonstrated that our strategy on three proteins and three replications all reached 100% coverage (except one with 98.85%) and 98.69-100% accuracy. It can also efficiently deal with the membrane protein, although the transmembrane region was missing due to the limitation of the MS. The three replicates reached 88.85-92.57% coverage and 97.57-100% accuracy. In sum, we provided a practical, robust, and accurate solution for full-length protein sequencing. The MuCS software is available at http://chi-biotech.com/mucs/.


Asunto(s)
Análisis de Secuencia de Proteína , Programas Informáticos , Algoritmos , Secuencia de Aminoácidos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Proteínas/genética , Análisis de Secuencia de ADN/métodos , Análisis de Secuencia de Proteína/métodos
8.
Reprod Biomed Online ; 45(3): 491-500, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35843780

RESUMEN

RESEARCH QUESTION: What factors affect the incidence of mosaic embryos resulting from assisted reproductive technology? DESIGN: A retrospective analysis of data from preimplantation genetic testing for aneuploidies in 544 couples was conducted using data from an electronic medical record database. RESULTS: Of 1910 embryos studied, 127 (6.6%) were mosaic. In multivariable logistic regression analysis, mosaicism incidence increased in embryos from IVF versus intracytoplasmic sperm injection (ICSI) (odds ratio [OR] 4.560, 95% confidence interval [CI] 2.800-7.424, P < 0.001), and in embryos from abnormal versus normal semen (OR 3.496, 95% CI 2.455-4.979, P < 0.001). Embryos tested using SurePlex 24Sure had lower mosaicism percentages than those tested using MALBAC-NGS and PicoPLEX GenetiSure (OR 2.726, 95% CI 1.532-4.852, P = 0.001; OR 2.389, 95% CI 1.537-3.711, P < 0.001, respectively). CONCLUSIONS: Semen quality, fertilization method and detection system are independent factors associated with embryonic mosaicism.


Asunto(s)
Mosaicismo , Diagnóstico Preimplantación , Aneuploidia , Blastocisto , Femenino , Fertilización In Vitro , Pruebas Genéticas/métodos , Humanos , Masculino , Embarazo , Diagnóstico Preimplantación/métodos , Estudios Retrospectivos , Semen , Análisis de Semen
9.
BMC Geriatr ; 22(1): 111, 2022 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-35144536

RESUMEN

BACKGROUND: The association between handgrip strength and depression in cancer survivors has been unexplored until now. We aim to examine the association between handgrip strength and depression in cancer survivors by using publicly available data (National Health and Nutrition Examination Survey). METHODS: Two waves of data from the National Health and Nutrition Examination Survey, from 2011-2012 and 2013-2014, were extracted and combined to explore this important issue. We extracted maximum patient handgrip strength value (from both hands). The Patient Health Questionnaire (PHQ-9) was used to evaluate depression with a cut-off > = 10 points indicating that patients had depressive symptoms. Other basic characteristics and health-related variables were also collected. We used Least Absolute Shrinkage and Selection Operator (LASSO) regression to select potential confounding factors. Multivariable linear or logistic regression models were adopted to explore whether handgrip strength as a continuous variable, or low handgrip strength, was associated with depressive symptoms. RESULTS: There were 876 cancer survivors in our present total sample, with 403 (46.0%) males and 473 females (54.0%). The mean (SD) age of the entire group was 64.67 (13.81) years. The prevalence of depression and low handgrip strength was 12.90% and 16.7%, respectively. The results showed that handgrip strength was negatively associated with depressive symptoms in cancer survivors (OR = 0.95, 95%CI:0.92-0.99; P = 0.024). In addition, after adjusting for age, gender, race; marital status, polypharmacy, sleep disorder, arthritis, congestive heart failure, history of stroke, type of cancer, chronic coronary bronchitis and being overweight, cancer survivors with low handgrip strength had a 2.02-fold risk of depression, compared to those with normal handgrip strength (OR = 2.02,95%CI:1.07-3.81; P = 0.028). CONCLUSIONS: Our present study suggests that low handgrip strength, as a simple and modifiable parameter, is associated with a higher risk of depression in cancer survivors. Therefore, future larger-scale prospective cohort studies are warranted to determine this association.


Asunto(s)
Supervivientes de Cáncer , Neoplasias , Estudios Transversales , Depresión/complicaciones , Depresión/diagnóstico , Depresión/epidemiología , Femenino , Fuerza de la Mano , Humanos , Masculino , Neoplasias/complicaciones , Neoplasias/epidemiología , Encuestas Nutricionales , Estudios Prospectivos
10.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(6): 1123-1128, 2022 Dec.
Artículo en Zh | MEDLINE | ID: mdl-36621797

RESUMEN

The clinical data of a female patient with dwarfism complicated with developmental dysplasia of the hip(DDH) treated in the Department of Joint Surgery of the First Affiliated Hospital of Hainan Medical College in September 2019 was analyzed.We summarized the experience in the treatment and reviewed the latest literature to determine the reasonable method for clinical diagnosis and treatment of dwarfism complicated with DDH.The improved lower limb function and satisfactory recovery of this patient after operation indicated that the treatment scheme was effective.Total hip arthroplasty is an effective method for the treatment of dwarfism complicated with DDH.Wagner prosthesis(SL-Cone)can achieve satisfactory short-term clinical results.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Enanismo , Luxación Congénita de la Cadera , Luxación de la Cadera , Prótesis de Cadera , Humanos , Femenino , Artroplastia de Reemplazo de Cadera/métodos , Luxación de la Cadera/cirugía , Luxación Congénita de la Cadera/complicaciones , Luxación Congénita de la Cadera/cirugía , Enanismo/complicaciones , Enanismo/cirugía , Resultado del Tratamiento , Estudios Retrospectivos
11.
Chin J Traumatol ; 24(3): 169-173, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33707100

RESUMEN

PURPOSE: This study was designed to compare the clinical efficacy of "8" and "0" wire fixation systems combined with double-head cannulated compression screws or Kirschner wires for the treatment of transverse patellar fractures. METHODS: From September 2011 to September 2018, patients with closed transverse patellar fractures treated with a double-head compression screw or Kirschner wire were included and analyzed retrospectively. Patients with patellar fractures combined with distal femoral fractures, tibial plateau fracture or preoperative lower limb dysfunction were excluded. The patients treated with the "8" tension band wire fixation system and Kirschner wire were taken as Group A; those treated with the "0" fixation system and Kirschner wire were taken as Group B; those treated with the "8" fixation system and double-head cannulated compression screw were taken as group C; and those treated with the "0" fixation system and double-head cannulated compression screw were taken as group D. Six weeks and one year after the operation and every month from the third month after the operation until the fractures healed, an X-ray examination was performed to identify fracture healing. The time of fracture healing and postoperative complications of the four groups were compared. One year after the operation, knee function was evaluated by Bostman's score. RESULTS: During the study period, 168 patients with patellar fractures were treated by operations, and 88 patients were excluded because the fracture type did not meet the requirements or because there were combined fractures of the distal femur or tibial plateau. As a result, 80 patients were included in this study, 20 in each group. All the patients were followed up for an average period of 12.2 months. Compared with Group A, patients in Group D presented less postoperative discomfort in the prepatellar region, quicker fracture healing, less fixation failure and better postoperative knee function scores (all p < 0.05). The incidence of internal fixation failure in Group (B+D) was lower than that in Group (A+C) (p > 0.05). CONCLUSION: The "0" wire fixation system combined with a double-head cannulated compression screw seems to be more beneficial than the other three fixation systems for the treatment of transverse patellar fractures.


Asunto(s)
Fracturas Óseas , Rótula , Hilos Ortopédicos , Fijación Interna de Fracturas , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/cirugía , Humanos , Rótula/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
12.
Cryobiology ; 93: 75-83, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32057735

RESUMEN

Cryopreservation of human spermatozoa with low concentration while maintaining adequate post-thawing motility remains a major challenge for male fertility preservation. A convenient and efficient ultra-rapid freezing method for small amounts of human spermatozoa in a closed Hemi-Straw carrier system (CHS) was developed. Spermatozoa from 60 healthy men were involved in a parameter refining test and another 15 extreme oligozoospermic specimens were assigned to a verification test. A commercialized sperm freezing medium, Quinn's Advantage® Sperm Freeze medium (glycerol and sucrose as the cryoprotective agent) was used in the study. The results showed that the highest recovery rates would be obtained via the method of 2 µl single droplet sequential interval loading, by placing the straw at 1 cm above the liquid nitrogen (LN2) surface for 60 s during freezing and 2 cm above the LN2 for 2 min during thawing. This method was applied in cryopreservation for the normozoospermic specimens and compared with a conventional slow freezing method. The results were better than those in the control group in the total motility recovery rate (77.8 ± 11.2% vs 56.6 ± 11.9%, P < 0.01), progressive motility recovery rate (77.6 ± 13.2% vs 47.7 ± 14.6%, P < 0.01), 24 h survival index (60.9 ± 13.4% vs 42.1 ± 14.1%, P < 0.01) and the sperm DNA fragment index (4.2 ± 3.7% vs 5.8 ± 3.7%, P = 0.126). This method was applied to the oligozoospermic specimens. Motile spermatozoa could be found in 12 of 15 cases in the ultra-rapid freezing group, while only in 7 cases in control group. The results indicated that this freezing method was simple, convenient and bio-safe for cryopreservation of severe oligozoospermic specimens.


Asunto(s)
Criopreservación/métodos , Preservación de Semen/métodos , Espermatozoides , Crioprotectores , Preservación de la Fertilidad , Congelación , Glicerol , Humanos , Masculino , Oligospermia , Motilidad Espermática , Sacarosa
13.
Sensors (Basel) ; 20(17)2020 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-32899388

RESUMEN

The non-linear characteristic of a non-contacting Inductive Proximity Sensor (IPS) with the temperature affects the computation accuracy when measuring the target distance in real time. The linear model based method for distance estimation shows a large deviation at a low temperature. Accordingly, this paper presents a non-linear measurement model, which computes the target distance accurately in real time within a wide temperature range from -55 °C to 125 °C. By revisiting the temperature effect on the IPS system, this paper considers the non-linear characteristic of the IPS measurement system due to the change of temperature. The proposed model adopts a non-linear polynomial algorithm rather than the simple linear Look-Up Table (LUT) method, which provides more accurate distance estimation compared to the previous work. The introduced model is fabricated in a 0.18 µm Complementary Metal Oxide Semiconductor (CMOS) process and packaged in a CQFN40. For the most commonly used sensing distance of 4 mm, the computed distance deviation of the Application-Specific Integrated Circuit (ASIC) chips falls within the range of [-0.2,0.2] mm. According to the test results of the ASIC chips, this non-linear temperature compensation model successfully achieves real-time and high-accuracy computation within a wide temperature range with low hardware resource consumption.

14.
Med Sci Monit ; 25: 5813-5822, 2019 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-31378778

RESUMEN

BACKGROUND This meta-analysis aimed to clarify the diagnostic role of plasma methylated SEPT9 (mSEPT9) in colorectal cancer (CRC) and examined its association with CRC. MATERIAL AND METHODS A systematic review was conducted prior to July 2018. Summary sensitivity, specificity, and positive and negative likelihood ratio (PLR/NLR) were calculated for the diagnostic value of mSEPT9 for CRC. The areas under the receiver operating curves (AUCs) were used to summarize the overall test performance. RESULTS Twenty-two studies with 2271 CRC patients were enrolled. The summary sensitivity, specificity, PLR, NLR, DOR, and AUC of the overall analysis of mSEPT9 were 0.69, 0.92, 8.1, 0.34, 24, and 0.89, respectively. Subgroup and meta-regression analyses demonstrated that the diagnostic value was higher for the Epi proColon 2.0 assay, Asian ethnicity, and mSEPT9 test combined with fecal occult blood test (FOBT) or fecal immunochemical test (FIT) than for other test methods, white ethnicity, and mSEPT9 test alone. The rate of mSEPT9 positivity was higher in advanced CRC cases compared with early-stage CRC cases, and was higher in CRC cases than in adenoma cases. No significant difference in mSEPT9 positivity rate was found between left- and right-sided CRC. CONCLUSIONS Plasma mSEPT9 has a high diagnostic value for CRC, especially on the newly developed Epi proColon test 2.0 method. The diagnostic sensitivity is superior among Asians compared to whites, and the combination of mSEPT9 and FOBT/FIT has a better performance than mSEPT9 alone. Finally, the expression of mSEPT9 is associated with CRC stage but not with location.


Asunto(s)
Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , Septinas/genética , Adenoma/patología , Área Bajo la Curva , Biomarcadores de Tumor/sangre , Neoplasias del Colon/patología , Neoplasias Colorrectales/patología , Metilación de ADN , Detección Precoz del Cáncer/métodos , Humanos , Estadificación de Neoplasias , Pronóstico , Sensibilidad y Especificidad , Septinas/sangre , Septinas/metabolismo
15.
Sensors (Basel) ; 19(9)2019 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-31086090

RESUMEN

The inductive proximity sensor (IPS) is applicable to displacement measurements in the aviation field due to its non-mechanical contact, safety, and durability. IPS can increase reliability of position detection and decrease maintenance cost of the system effectively in aircraft applications. Nevertheless, the specialty in the aviation field proposes many restrictions and requirements on the application of IPS, including the temperature drift effect of the resistance component of the IPS sensing coil. Moreover, reliability requirements of aircrafts restrict the use of computational-intensive algorithms and avoid the use of process control components. Furthermore, the environment of airborne electronic equipment restricts measurements driven by large current and proposes strict requirements on emission tests of radio frequency (RF) energy. For these reasons, a differential structured IPS measurement method is proposed in this paper. This measurement method inherits the numerical separation of the resistance and inductance components of the IPS sensing coil to improve the temperature adaptation of the IPS. The computational complexity is decreased by combining the dimension-reduced look-up table method to prevent the use of process control components. The proposed differential structured IPS is equipped with a differential structure of distant and nearby sensing coils to increase the detection accuracy. The small electric current pulse excitation decreases the RF energy emission. Verification results demonstrate that the differential structured IPS realizes the numerical decoupling calculation of the vector impedance of the sensing coil by using 61 look-up table units. The measuring sensitivity increased from 135.5 least significant bits (LSB)/0.10 mm of a single-sensing-coil structured IPS to 1201.4 LSB/0.10 mm, and the linear approximation distance error decreased from 99.376 µm to -3.240 µm. The proposed differential structured IPS method has evident comparative advantages compared with similar measuring techniques.

16.
Biochem Biophys Res Commun ; 503(2): 665-670, 2018 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-29908183

RESUMEN

Ischemia and oxidative stress play crucial roles in the pathophysiology of sudden sensorineural hearing loss (SSNHL). Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine and serves an important role in hearing function. The present study was designed to evaluate the effect of MIF on oxygen-glucose deprivation (OGD)-induced ototoxicity and to elucidate its molecular mechanism. In HEI-OC1 auditory cells, OGD reduced cell viability and increased supernatant lactate dehydrogenase (LDH) and MIF in a time-dependent manner. However, the reduced cell viability exerted by OGD was attenuated by antioxidant and MIF. Luciferase reporter assay demonstrated that MIF could activate NF-E2-related factor 2 (Nrf2), and real-time PCR showed increased mRNA expressions of Nrf2 and two Nrf2-responsive genes, including heme oxygenase-1 (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO1). MIF also suppressed oxidative stress induced by OGD, as demonstrated by decreased MDA and increased GSH in cellular supernatant. Inhibition of Nrf2 using siRNA suppressed HO-1 protein expression, the protective effect on OGD-induced injury and decrease in oxidative stress by MIF. Moreover, MIF prevented OGD-induced reduction of Akt1 phosphorylation at Ser473. LY294002, an inhibitor of PI3K/Akt signaling, attenuated the enhancement of Nrf2 protein and protective effect of MIF in OGD-treated cochlear cells. We demonstrate that MIF protects cochlear cells against OGD-induced injury through activation of Akt-Nrf2-HO-1 pathway.


Asunto(s)
Cóclea/metabolismo , Hemo-Oxigenasa 1/metabolismo , Oxidorreductasas Intramoleculares/metabolismo , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Daño por Reperfusión/metabolismo , Transducción de Señal , Animales , Hipoxia de la Célula , Línea Celular , Cóclea/citología , Cóclea/patología , Glucosa/metabolismo , Ratones , Estrés Oxidativo , Oxígeno/metabolismo , Daño por Reperfusión/patología
17.
Biochem Biophys Res Commun ; 499(2): 112-119, 2018 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-29470982

RESUMEN

Traumatic brain injury (TBI) is a leading cause of disability and mortality in young adults worldwide. The pathophysiology is not fully understood. Programmed necrosis (necroptosis) is a newly identified mechanism of cell death combining features of both apoptosis and necrosis. Receptor-interacting protein 3 (RIP3) plays an important role in programmed necrosis. However, the effect of RIP3-related pathway in TBI is little to be known. We attempted to explore the significance of RIP3 in regulating TBI in vivo. Significantly, TBI induced over-expression of RIP3 in the hippocampus of mice, as well as RIP1 and phosphorylated mixed lineage kinase domain-like protein (MLKL). Mice after TBI exhibited cognitive dysfunction and activation of glia cells, which were significantly attenuated by RIP3-knockout (KO). Moreover, inflammation and oxidative stress in hippocampus were markedly induced by TBI in wild type (WT) mice. Of note, the reduction of pro-inflammatory cytokines and oxidants was observed in RIP3-deficient mice, which was linked to the blockage of NLR pyrin domain containing 3 (NLRP3)/apoptosis-associated speck-like protein containing a CARD (ASC)/Caspase-1 and kelch-like ECH-associated protein 1 (Keap 1) pathways. Further, TBI induced hippocampus apoptosis, evidenced by the increase of cleaved Caspase-8/-3 and poly (ADP)-ribose polymerase (PARP) in WT mice, whereas being decreased by RIP3-knockout. In addition, RIP3 knockout led to phosphorylation of AMP-activated protein kinase α (AMPKα) in hippocampus of mice after TBI. And of note, the in vitro findings indicated that RIP3-ablation attenuated oxidative stress, inflammation and apoptosis in astrocytes, which was dependent on AMPKα activation. Together, suppressing RIP3 might be served as a therapeutic target against brain injury through inhibiting inflammation, oxidative stress and apoptosis.


Asunto(s)
Adenilato Quinasa/metabolismo , Apoptosis , Lesiones Traumáticas del Encéfalo/enzimología , Lesiones Traumáticas del Encéfalo/prevención & control , Inflamación/patología , Estrés Oxidativo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/deficiencia , Transducción de Señal , Animales , Astrocitos/enzimología , Astrocitos/patología , Lesiones Traumáticas del Encéfalo/patología , Lesiones Traumáticas del Encéfalo/fisiopatología , Cognición , Constricción Patológica , Eliminación de Gen , Hipocampo/patología , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo
18.
Int J Hyperthermia ; 34(8): 1298-1303, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29506421

RESUMEN

OBJECTIVE: To investigate the factors which may cause thermal injury of abdominal wall structures in ultrasound-guided high-intensity focussed ultrasound (USgHIFU) ablation of uterine fibroids. METHOD: A total of 892 patients with uterine fibroids diagnosed on contrast-enhanced magnetic resonance imaging (MRI) scans received HIFU ablation and follow-up MRI scanning. After therapy, thermal injury to the skin was assessed via measurement of skin redness, blisters, subcutaneous nodules and to the abdominal wall structures via measurement of signal intensity on T2-weighted MRI images. A total of 151 patients were assigned to the injury group, 741 patients were assigned to the non-injury group. The relationship between patient and treatment parameters and injury were analysed using univariate and multiple logistic regression analyses. RESULTS: Univariate logistic regression revealed that sonication time, sonication time per hour, total energy deposited, distance from uterine fibroid ventral side to skin, volume of uterine fibroids, abdominal wall scar, abdominal wall thickness and body mass index (BMI) all affected whether thermal injury occurred (p < 0.05). Subsequently, multiple logistic regression analysis revealed that total energy (p = 0.000, OR = 2.228, 95% CI 1.831-2.712), abdominal wall scar (p = 0.019, OR = 1.639, 95% CI 1.085-2.477) and abdominal wall thickness (p = 0.000, OR = 1.562, 95% CI 1.313-1.857) were significantly correlated with thermal injury. CONCLUSION: Multiple logistic regression analysis revealed that abdominal wall thickness, total energy and abdominal wall scar were the most significant influencing factors that influenced minimal thermal injury of abdominal wall structures in USgHIFU ablation of uterine fibroids.


Asunto(s)
Quemaduras/etiología , Ultrasonido Enfocado de Alta Intensidad de Ablación/efectos adversos , Leiomioma/cirugía , Neoplasias Uterinas/cirugía , Pared Abdominal , Adulto , Femenino , Humanos , Leiomioma/diagnóstico por imagen , Imagen por Resonancia Magnética , Persona de Mediana Edad , Piel , Neoplasias Uterinas/diagnóstico por imagen
19.
Chem Biodivers ; 14(5)2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28130826

RESUMEN

One new ent-kaurane diterpenoid, 11ß,16α-dihydroxy-ent-kauran-19-oic acid (1), together with eight known analogues 2 - 9 were isolated from the aerial parts of Wedelia prostrata. One of the acidic diterpenoids, kaurenoic acid (3), was converted to seven derivatives, 10 - 16. All compounds were evaluated for their cytotoxic activity in vitro against human leukemia (K562), liver (HepG-2), and stomach (SGC-7901) cancer cell lines. Only four kaurenoic acid derivatives, 13 - 16, with 15-keto and substitutions at C(19) position, exhibited notable cytotoxic activities on these tumor cell lines with IC50 value ranging from 0.05 to 3.71 µm. Compounds 10 - 12, with oxime on C(15) showed moderate inhibitory effects and compounds 1 - 9 showed no cytotoxicities on them. Structure-activity relationships were also discussed based on the experimental data obtained. The known derivative, 15-oxokaurenoic acid 4-piperdin-1-ylbutyl ester (17), induced typical apoptotic cell death in colon SW480 cells upon evaluation of the apoptosis-inducing activity by flow-cytometric analysis.


Asunto(s)
Diterpenos/aislamiento & purificación , Diterpenos/toxicidad , Wedelia/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Diterpenos de Tipo Kaurano/aislamiento & purificación , Células Hep G2 , Humanos , Concentración 50 Inhibidora , Células K562 , Componentes Aéreos de las Plantas/química , Relación Estructura-Actividad
20.
Sensors (Basel) ; 17(7)2017 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-28665320

RESUMEN

Inductive proximity sensors (IPSs) present a unique no-contact advantage. They are widely preferred for displacement measurement in various industrial fields (e.g., aviation and aerospace), and they are improved continuously. When the inductance and resistance components of the IPS sensing core are separated, the influence of temperature drift on measurement can be eliminated. The complexity of online computation of component separation can be reduced using a two-dimensional look-up table method. However, this method exhibits disadvantages, such as large capacity of the look-up table, dependency on precision measurement of sensing core parameter, and nonlinear distribution of measurement resolution. This study aims to overcome these disadvantages by examining the nonlinear relationship between the response of the sensing core and the ambient temperature, and proposes a dimension-reduced measurement method. The proposed method extracts the characteristics of the response curves at two temperatures and calculates the characteristics of the response curves at any temperature using a linear approximation. The look-up table capacity is less than 0.37% of the two-dimensional look-up table capacity (condensed) under the same condition; dimension reduction enables the construction of a complete look-up table directly by calibration procedures and avoids precise measurement on sensing core parameters; the calibration procedures establish uniform mapping of the distribution of measurement resolution. The experiment shows that, when the measurement ranges are 0-6, 0-5, and 0-4 mm, the maximum measurement errors are 0.140, 0.065, and 0.040 mm, respectively, under temperature ranging from 20 ∘ C to 110 ∘ C. This study extends the measurement range from 0-5 mm to 0-7 mm and improves the measurement accuracy over 0.1 mm (50% at 5 mm) compared with the two-dimensional look-up table method. Therefore, the proposed method not only inherits the advantages of the original method but also achieves the above-mentioned expected capacity improvements effectively.

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