Electrical Impedance Method Research Articles

P-1827. Novel Evaluation System for Aspergillus fumigatus Interactions with Human Cells via Combination of Imaging and Electrical Impedance

Abstract Background Aspergillus fumigatus is a major fungal pathogen causing pulmonary aspergillosis, an important disease associated with transplantation and immunosuppression. However, the interactions between A. fumigatus and human cells are not well understood. This study evaluated the interaction of A. fumigatus with THP-1 macrophages and A549 lung epithelial cells using fluorescence imaging and electrical impedance measurements to monitor fungal growth and cellular damage continuously.Figure 1.Schematic diagram of the relationship between electrical impedance and cell damage Methods The experimental setup used xCELLigence eSight (Agilent) and a specialized 96-well plate with electrodes at the bottom to measure impedance changes as cells adhered or detached (Figure 1). THP-1 and A549 cells were cultured, then infected with fluorescent A. fumigatus conidia. In addition, antifungal drugs (micafungin, caspofungin, voriconazole, isavuconazole, amphotericin B) were added to this experimental system at broth microdilution method and tested.Figure 2.Macrophage and A. fumigatus (MOI 4.0) in relation to each antifungal agentA:Voriconazole(VRCZ), B : Amphotericin B (AMPH-B) Results Results showed A. fumigatus filament growth leading to decreased impedance indicative of cell damage in both cell types, with faster damage at higher conidial loads. Fluorescence showed echinocandins inhibited hyphal growth but did not prevent impedance drops. Voriconazole and isavuconazole prevented impedance drops at clinically relevant concentrations (Figure 2A). Amphotericin B caused rapid impedance drops at high doses, suggesting direct cytotoxicity (Figure 2B). Conclusion A549 epithelial cells survived longer than macrophages, suggesting they play a defensive role against A. fumigatus. Impedance changes correlated with visual antifungal effects for azoles and amphotericin B but not echinocandins. This system enables evaluating fungal-host interactions using different cell types and fungi. Combining impedance with fluorescence imaging provides a comprehensive and objective assessment of antifungal activity and cellular responses. Disclosures Hiroshi Kakeya, MD, PhD, Asahikasei Phrma: Honoraria|GSK: Honoraria|MSD: Honoraria|Pfizer: Honoraria|Shionogi: Honoraria|Sumitomo Parma: Honoraria

Application of the electrical impedance method to steel/steel EHD point contacts

The authors have previously developed the electrical impedance method which simultaneously measure the thickness and breakdown ratio of oil films in EHD (elastohydrodynamic) contacts. Furthermore, using a ball-on-disc-type apparatus, the authors have also confirmed that the accuracy of oil film measurement by the developed method is comparable to that of optical interferometry (i.e., glass-steel contacts). In this study, we discussed the experimental results obtained by applying the electrical impedance method to steel-steel contacts using a steel disc instead of a glass disc. It was found that under the mixed lubrication regime where wear occurs, the oil film thickness obtained by this method is calculated to be significantly thicker than the theoretical value. This can be attributed to the increase in the apparent dielectric constant of the lubricant due to wear particles in the lubricant.

Impedance measurement of rolling bearings using an unbalanced AC wheatstone bridge

Industry 4.0 drives the demand for cost-efficient and reliable process data and condition monitoring. Therefore, visualizing the state of tribological contacts becomes important, as they are regularly found in the center of many applications. Utilizing rolling element bearings as sensors and monitoring their health by the electrical impedance method are promising approaches as it allows, e.g., load sensing and detection of bearing failures. The impedance cannot be measured directly, but there are various methods available. This paper discusses advantages and disadvantages and suggests the AC Wheatstone bridge as a reliable way of measuring impedances with low phase angles at sampling rates in the kHz range. The corresponding equations are introduced, a simulation built, an uncertainty mode and effects analysis carried out and sample measurement results of real rolling elements shown. It can be demonstrated that the AC Wheatstone bridge meets the proposed requirements for sensory utilization and condition monitoring when the bearing is operated in the hydrodynamic regime.

A-147 Comparative Precision of Platelet Counting by Optical, Fluorescent, and Impedance Techniques in Thrombocytopenia and Microcytosis Patients

Abstract Background In today's era of automation driven by Artificial Intelligence, even the most efficient automated hematology analyzer may struggle to accurately determine platelet count in patients with low platelet count and microcytosis. The Sysmex XN-series analyzer (Sysmex, Kobe, Japan) uses optical density, fluorescence, and electronic impedance methods for platelet counting. This study aimed to evaluate the accuracy of optical, fluorescence, and electrical impedance methods in estimating precise platelet counts in thrombocytopenic and microcytic patient samples. Methods A cross-sectional study was conducted in the Department of Laboratory Medicine at AIIMS, New Delhi, for 30 days consecutively. A total of 200 blood samples collected, of which 100 samples were of thrombocytopenia (<100x10^9/L) and 100 samples were of microcytosis (Mean corpuscular volume <76 femtoliters). MCV<76 fl was further categorized into 2 groups- MCV 60-70 fl and MCV 71-76 fl accordingly. Males and females were categorized and analyzed distinctly for thrombocytopenia and microcytosis. Statistical analysis was performed using SPSS 16.0 for Windows (SPSS Inc., Chicago, IL, USA) and the Bland Altman plot was analyzed. Results Of the 100 patients with thrombocytopenia (platelet<1 lakh/L) females were predominantly 54% while males were 46% and the median age was 29 years (0.02-70). Of the 100 patients with low MCV (<76 fl) females were 53%, while males were 47% and the median age was 29 years (0.3-69). The findings were compared against the standard manual platelet count method in peripheral smears verified by two expert pathologists. The Bland Altman plot for Platelet <1 lakh/L and MCV <76 fl were compared with standard manual platelet count method and the following findings were obtained i) In female with PLT- <1 lakh/L, PLT-O showed least bias (9.8) followed by PLT-F (10.4) and PLT-I (12.1) ii) In males with PLT-<1 lakh/L, PLT-O showed least bias(14.1) followed by PLT-F(16.5) and PLT-I(17.0) iii) For MCV 61-70fl, PLT-O showed the least bias (4.4) followed by PLT-F (6.7) and PLT-I (28.5) iv)For MCV 71-76fl, PLT-F showed least bias (-0.2) followed by PLT-O (1.5) and PLT-I(31.2). Conclusions Platelet count by optical method (PLT-O) detects platelet count more accurately with minimum bias when compared with PLT-F and PLT-I in patients with thrombocytopenia. In patients with microcytosis, PLT-I is less reliable in comparison to PLT-O and PLT-F. A limitation of the automated hematology analyzer is the inability to detect platelet clumps which is appreciated in peripheral smears.

Effects of temperature on electrical impedance of biological tissues: ex-vivo measurements.

Bioelectrical impedance techniques have been useful in various applications, including body composition analysis, impedance plethysmography, impedance cardiography, lung ventilation, perfusion, and tissue characterization. Electrical impedance methods have also been useful in characterizing different foods like meat, fruits, and beverages. However, the temperature of tissue samples can change their dielectric properties, affecting their impedance. This research investigated the effects of temperature on the impedance of various biological tissues over the frequency range of 10 Hz to 5 MHz. Freshly excised animal tissues (lamb, cow, chicken), fish, fruits, and plants were considered as biological samples. The samples were placed in a test cell and submerged in a water bath heated by a hot plate to vary the temperature. Impedance measurements were conducted using a bioimpedance spectrometer in 2 °C steps within the temperature range of 20 °C to 50 °C. Impedance values decreased with increased temperature across all measurement frequencies for all biological samples. Curve fitting indicated that impedance decreased linearly with temperature, with a mean correlation coefficient of 0.972 for all samples. For all biological samples under investigation, the relative impedance change ranged from -0.58% to -2.27% per °C, with a mean and standard deviation of (-1.42±0.34) %/°C. On average, animal samples exhibited a higher relative temperature coefficient of -1.56% per °C (±0.41) across the frequency range, compared to -1.31% per °C (±0.26) for fruit and vegetable samples. Additionally, the relative temperature coefficient values were generally higher at lower frequencies than at higher frequencies. The findings of this research can be valuable for studies or biomedical applications involving variable tissue temperatures.

Verification of the Electrical Impedance Method for Measuring the Humidity of Silicate Material

Measuring humidity in building materials is of great importance in assessing the condition of materials and also in building diagnostics, as the presence of humidity affects their physical and thermal insulation properties. In the construction industry, the use of non-destructive electrical measurement methods for testing the physico-chemical properties of materials is common and especially the electrical conductivity of materials is significantly affected by humidity.

Association of SLC6A4 gene c.*670T>G polymorphism with the risk for asthma and peripheral blood cytological characteristics among ethnic Zhuang Chinese population

To assess the association of SLC6A4 gene c.*670T>G polymorphism with the risk for asthma and peripheral blood cytological characteristics among ethnic Zhuang Chinese from Guangxi, China. From May 2017 to March 2020, 258 patients diagnosed with asthma and 244 healthy controls were recruited from the Affiliated Hospital of Youjiang Minzhu Medical College and the People's Hospital of Hechi. Genotypes of the c.*670T>G polymorphism were determined by Sanger sequencing. Flow cytometry was used in combination with an electrical impedance method for the counting and classification of peripheral blood cells. Compared with the T allele, the G allele of the c.*670T>G polymorphism was associated with the risk for asthma in the population (OR = 1.54, 95%CI = 1.15-2.06; P = 0.004). Compared with the GT and TT genotypes, homozygous GG genotype also comprised a risk factor (OR = 1.66, 95%CI = 1.16-2.38; P = 0.005). Stratification of the risk factors showed that the homozygous GG genotype has increased the risk of asthma in males and urban residents (P < 0.01). The erythrocyte, hemoglobin and platelet counts of the asthma group were significantly higher than the control group (P < 0.001). The GG, GT and TT genotypes have respectively accounted for 82.35%, 17.65% and 0% of the samples with platelets exceeding the normal value. The overall platelet level of GG genotype was higher than GT+TT genotype (P < 0.05). The significant association was verified by the false positive report probability, and at a prior probability level of 0.1, G vs. T false positive probability was 0.071, and GG vs. GT+TT false positive probability was 0.153. The GG genotype of the c.*670T>G polymorphism is associated with the risk for asthma among ethnic Zhuang Chinese from northwest Guangxi. Above finding has also enriched the genotypic data and peripheral blood phenotype for this polymorphism.

The role of segmental bioelectrical impedance technique in the assessment of intraperitoneal ultrafiltration volume with peritoneal dialysis patients

Objective To investigate the role of segmental bioelectrical impedance technique (SBIA) in the assessment of intraperitoneal ultrafiltration volume with peritoneal dialysis patients. Method We selected the patients at the Department of Nephrology of the First Affiliated Hospital of Zhengzhou University and measured the segmental bioelectrical impedance by a German Fresenius body composition analyzer (the Fresenius whole body composition measurement (BCM) machine was used as a segmental machine in this study). An alternating current (5 kHz, 0.05–0.7 mA) was continuously released during the measurement. The released current penetrated the peritoneal cavity on both sides of the body, from which the segmental resistance at a frequency of 5 kHz was obtained from the multifrequency data (R5/Ω). Baseline BIA measurements were initiated after the patient entered the supine position for 5–10 min, then dialysate was instilled into the peritoneal cavity. BIA measurements were performed at 10-min intervals during the retention of dialysate in the abdomen and finally ended when dialysate drainage was complete. Real-time intraperitoneal volume estimated by SBIA (IPVSBIA)and ultrafiltration volume estimated by SBIA(UFVSBIA) was calculated. At the same time, the actual ultrafiltration volume at the end of peritoneal dialysis was weighed and measured (UFVMEA). Results A total of 30 patients were included in the study, 9 patients withdrew from the study due to subjective factors during the measurement process, and 21 patients completed the study. The correlation coefficient R 2 of UFVSBIA and UFVMEA was 0.21 (p < 0.05). Bland-Altman analysis showed that the bias of UFVSBIA to the actual UFVMEA was 0.12 L, and the 95% agreement limit was between −0.5 L and 0.74 L, which confirmed that UFVSBIA measured by electrical impedance method and UFVMEA measured by weighing method were in good agreement. The time required to reach the maximum ultrafiltration volume (UFVSBIA) was 108 ± 68 min, and the mean value of the maximum ultrafiltration volume (Max UFVSBIA) was 1.16 ± 0.60 L. Conclusion The segmental bioelectrical impedance technique can be used to assess the intraperitoneal ultrafiltration volume of peritoneal dialysis patients in real-time and effectively. This method may guide the dialysis fluid retention time and the maximum ultrafiltration volume in PD patients.

The Relationship Between Phase Angle Obtained from the Maximum Reactance and Fasting Glucose, Hemoglobin A1c in Type 2 Diabetes Mellitus

Aim: The phase angle obtained from the maximum reactance (PA max) is a better potential indicator than the phase angles obtained from multiple frequencies. Our aim in this study is to investigate the correlation of PA max with fasting glucose and hemoglobin A1c in Type-2 Diabetes Mellitus (T2 DM).&#x0D; Material and Methods: The study was conducted prospectively, two groups were formed as T2 DM (n=75) and healthy controls (n=32) and their demographic variables were examined. Right hand, left hand, right leg, left leg, hand leg and leg leg segment measurements were taken with electrical impedance method and phase angle was obtained at maximum reactance. Correlations with fasting glucose, hemoglobin A1c and other variables were examined.&#x0D; Results: Fasting glucose, glycated hemoglobin A1c, age, body mass index, body fat percentage were found to be significantly higher in the T2 DM group compared with the healthy group. However, RH PA max, RL PA max, LL PA max, H_L PA max, and L_L PA max values were found to be significantly lower than in the healthy group. In T2 DM group, hemoglobin A1c was found significantly negative correlated with PA max in all segments, while fasting glucose is negatively correlated with all segments except LH Pamax.&#x0D; Conclusion: PA max is significantly reduced by the impaired glycemic index in T2 DM and is a potential marker reflecting metabolic status.

Monitoring optoporated process on mammalian cells by real-time measurement of membrane resealing time.

Resealing time based loading efficiency of optoporation is the key parameter for drug or gene delivery. This work describes a comparatively simple optical approach to directly measure the cell membrane resealing time of the gold nanoparticle mediated photoporation. To establish a membrane potential detection optical system, which can provide a direct measurement of resealing time of the optoporated cells. Voltage sensitive dye has been used to label the gold nanoparticle covered cell before laser activation and the resealing time was estimated from the voltage change due to the fluorescence light intensity change before and after laser activation. The approach has been validated by the simulated data based on diffusion model and Monte Carlo simulation and the experimental data obtained from a flow cytometry analysis. The measured resealing time after perforation varied from 28.6 to 163.8s on Hela cells when the irradiation fluence was increased, with a correlation coefficient () of 0.9938. This result is in agreement with the resealing time (1-2min) of photothermal porated Hela cells measured by electrical impedance method. The intracellular delivery efficiency of extracellular macromolecular under the same irradiation fluence depends mainly on diffusion velocity rather than pore size. The method described here can be used to directly measure resealing time of optoporated cells for accurately estimating the loading efficiency on discovering the mechanism of optoporation.

BMI in Evaluating Obesity of Contemporary College Students

Background: Changes in lifestyle and reduction in physical activity have led to a continuous increase in the number of obese people in my country, but the criteria for determining obesity are different. Body mass index (BMI) is the most commonly used indicator for obesity research. Objective: To evaluate the authenticity, reliability and profitability of the obesity determination standard of body mass index (BMI) of college students, using the body fat rate obesity determination standard proposed by the National Center for Disease Control and Prevention as the gold standard, and to discuss BMI as a diagnostic performance and suitable cut-off value for excess body fat percentage. Methods: 1208 college students (557 males and 651 females) were tested, the height and weight were measured to calculate BMI, and the electrical impedance method was used to measure the percentage of body fat (BF%) and the ROC curve cutoff value to construct the BMI obesity diagnosis. standard. Results: The authenticity evaluation of BMI as an obesity screening standard showed high specificity and false negative rate, but low false positive rate and sensitivity; especially for women, the sensitivity was 0.05. Males had higher crude concordance and Youden index than females. When the overall cut-off value of ROC curve analysis was 23.05kg/m², the specificity and sensitivity were high; when the cut-off values for men and women were 23.67kg/m² and 23.35kg/m², the sensitivity was low, the specificity was high, and the misdiagnosis rate was low; BF% was used as the When determining the criteria, the diagnostic performance of BMI and male and female groups was good. Conclusion: When the BMI criterion is 28kg/m², the overall sensitivity is low and male is higher than that of female; the overall specificity is high and the misdiagnosis rate is low. When the BMI obesity diagnosis value is 23.05kg/m², it can effectively improve the sensitivity, reduce the missed diagnosis rate, reduce the missed diagnosis of "occult obesity", improve the evaluation of obesity in the population, and miss the opportunity for intervention.

Lubrication Condition Monitoring in EHD Line Contacts of Thrust Needle Roller Bearing Using the Electrical Impedance Method

In this study, we developed the electrical impedance method which simultaneously measures the thickness and breakdown ratio of oil films in elastohydrodynamic (EHD) line contacts within thrust needle roller bearings. Initially, we theoretically demonstrated that the oil film thickness and breakdown ratio can be simultaneously measured using the complex impedance that is produced when an AC voltage is applied to EHD line contacts. To verify the measurement accuracy of the electrical method, we monitored the oil film thickness of a thrust needle roller bearing and compared it with the theoretical value. The results revealed that the oil film thickness was thinner than the theoretical value immediately after starting the test, with the breakdown ratio being greater than 0 (indicating mixed lubrication); however, the breakdown ratio decreased over time, and the oil film thickness nearly matched the theoretical value one hour after starting the test, when it is believed that running-in wear is complete (i.e., breakdown ratio ≈ 0). Furthermore, following the test, after examining the race surface, we confirmed that running-in wear had indeed occurred. These results suggest that the developed method can monitor the lubrication conditions in EHD line contacts, such as those in thrust needle roller bearings, in detail.

Synergistic Action of MCL-1 Inhibitor with BCL-2/BCL-XL or MAPK Pathway Inhibitors Enhances Acute Myeloid Leukemia Cell Apoptosis and Differentiation.

Acute myeloid leukemia (AML) is a hematological malignancy characterized by excessive proliferation of abnormal myeloid precursors accompanied by a differentiation block and inhibition of apoptosis. Increased expression of an anti-apoptotic MCL-1 protein was shown to be critical for the sustained survival and expansion of AML cells. Therefore, herein, we examined the pro-apoptotic and pro-differentiating effects of S63845, a specific inhibitor of MCL-1, in a single-agent treatment and in combination with BCL-2/BCL-XL inhibitor, ABT-737, in two AML cell lines: HL-60 and ML-1. Additionally, we determined whether inhibition of the MAPK pathway had an impact on the sensitivity of AML cells to S63845. To assess AML cells' apoptosis and differentiation, in vitro studies were performed using PrestoBlue assay, Coulter electrical impedance method, flow cytometry, light microscopy and Western blot techniques. S63845 caused a concentration-dependent decrease in the viability of HL-60 and ML-1 cells and increased the percentage of apoptotic cells. Combined treatment with S63845 and ABT-737 or MAPK pathway inhibitor enhanced apoptosis but also induced differentiation of tested cells, as well as altering the expression of the MCL-1 protein. Taken together, our data provide the rationale for further studies regarding the use of MCL-1 inhibitor in combination with other pro-survival protein inhibitors.

Analysis of Heat Flow for In Vitro Culture Monitored by Impedance Measurement

The paper proposes an innovative method of using microheaters for research on cells in vitro. A method of local heating of a single culture well, compatible with an Electric Cell-substrate Impedance (ECIS) system is presented. A microheater and culture well system for cell culture was modelled. Electrical and thermal simulation of the system under operating conditions was carried out. Correct distribution of heat was observed at the site of the cell culture suspension in the medium, while not affecting the conditions in adjacent wells. As part of the experiment, a heating element of nichrome (NiCr) was created using the magnetron sputtering process. Electrical and thermal measurements of the manufactured device were carried out. It has been shown that it is possible to establish the desired temperature over the long term. In addition, the structures made were characterised by work stability, precision in maintaining the right temperature, and the possibility of being controlled with high accuracy. There is a problem with the precise and reproducible carrying out of a cell culture experiment that differs only in the process temperature. In this work, a technique for increasing the temperature locally, in a single culture well, in a medium containing eight such wells was proposed and analyzed. The use of this method will allow avoidance of the impact of potential changes in parameters other than temperature on the culture. That may occur when comparing cells grown at different temperatures by means of the ECIS (Electric Cell-substrate Impedance) method.

P030: Baseline IgM amount can identify patients with adverse outcome despite a PET-2 adapted treatment in classical Hodgkin Lymphoma: results from a real-life single-center study i

Background: Hodgkin Lymphoma is characterized by an inflammatory background in which the reactive myeloid cells may exert an immune suppressive effect that advances progression of disease. Immunoglobulin M is first antibody isotype to be produced during an immune response, but it plays also an immunoregulatory role, therefore we investigated if it could have any clinical impact on prognosis. Experimental design: In this retrospective, observational, single – center study, we evaluated 212 newly diagnosed Hodgkin Lymphoma (HL) patients, including 132 advanced stage cases, with a median follow up of 60.3 months (range 60–204); 109 (51%) were men, with a median age of 31 years (range 15–77), 64 patients showed bulky disease, while 119 suffered from B symptoms at the onset. The median baseline values for IgM, IgA and IgG were, respectively: 86.0 (range 5.0–336.0 mg/dL), 197.5 (range 5.0–336.0 mg/dL) and 1110.00 (range 157.0–2763.0 mg/dL). 49/212 (23%) patients had a baseline IgM value lower than 50mg/dL. White blood cell count and type were determined by electrical impedance method. Nephelometry was used for immunoglobulins quantification. Results: PFS at 60 months was 54.1% versus 81.1 % respectively in patients with IgM ≤50 mg/dL or IgM>50 mg/dL (p<0.001). A level of 50 mg/dl of IgM at baseline resulted in 84.1% sensitivity and 45.5% specificity in predicting achievement of complete response in the whole cohort (area under curve - AUC - 0.62, p=0.013). In multivariate analysis, only baseline IgM ≤50 mg/dl and presence of large nodal mass (< 7 cm) were independent baseline variables able to predict clinical outcome while after two cycles of treatment only IgM ≤50 mg/dl at baseline and PET-2 status were independent predictors of PFS. Thus, we stratified the advanced stage patients in three groups based on clinical variables available at diagnosis: low risk group was defined as absence of LNM and baseline IgM >50; standard-risk was defined by either presence of LNM or baseline IgM ≤50 mg/dL; high risk group was defined by both presence of LNM and IgM ≤50 mg/dL at baseline. The 60-months PFS estimates were significantly different among the three groups, respectively 83.5, 59.5 and 40.0%, p=<0.0001. Conclusion: IgM amount at diagnosis is a valuable prognostic factor much earlier than PET-2 and it can also provide information in PET-2 negative patients. This can help identify at baseline different HL classes at risk of treatment failure.

Evaluation of gastric emptying in critically ill patients using electrical impedance method: a pilot study

Nasogastric feeding is commonly used to deliver enteral feed in critically ill patients and several methods are used for assessing the gastric residual volume with limitations. A new approach for gastric emptying time measurement has been developed using Electric Impedance Method (EIM). The study aims to establish whether EIM is useful for measuring gastric emptying during nasogastric feeding compared with nasogastric suction. The pilot study was performed among the patients in the Intensive Care Unit (ICU), Bangladesh, from 2018 to 2019. Enteral feed was given to patients by NG tube. Gastric emptying and Gastric Residual Volume (GRV) were measured using EIM and nasogastric suction tube. Patterns of filling and emptying were almost the same in all subjects but emptying time varied between individuals that correlated well with GRV in 16 patients. Therefore, the study showed that the measurement of gastrc volume by the non-invasive and hazard-free electrical impedance method has a high specificity (90%) and efficacy of 80%. The study also revealed significant changes in gastric emptying time due to different body statuses. EIM seemed to be capable of measuring gastric emptying over time. EIM could become a standard tool for monitoring gastric emptying in patients at risk of gastroparesis.

Altered electrical properties in skeletal muscle of mice with glycogen storage disease type II

Electrical impedance methods, including electrical impedance myography, are increasingly being used as biomarkers of muscle health since they measure passive electrical properties of muscle that alter in disease. One disorder, Pompe Disease (Glycogen storage disease type II (GSDII)), remains relatively unstudied. This disease is marked by dramatic accumulation of intracellular myofiber glycogen. Here we assessed the electrical properties of skeletal muscle in a model of GSDII, the Pompe6neo/6neo (Pompe) mouse. Ex vivo impedance measurements of gastrocnemius (GA) were obtained using a dielectric measuring cell in 30-week-old female Pompe (N = 10) and WT (N = 10) mice. Longitudinal and transverse conductivity, σ, and the relative permittivity, εr, and Cole–Cole complex resistivity parameters at 0 Hz and infinite frequency, ρo and ρ∞, respectively, and the intracellular resistivity, ρintracellular were determined from the impedance data. Glycogen content (GC) was visualized histologically and quantified biochemically. At frequencies > 1 MHz, Pompe mice demonstrated significantly decreased longitudinal and transverse conductivity, increased Cole–Cole parameters, ρo and ρo-ρ∞, and decreased ρintracellular. Changes in longitudinal conductivity and ρintracellular correlated with increased GC in Pompe animals. Ex vivo high frequency impedance measures are sensitive to alterations in intracellular myofiber features considered characteristic of GSDII, making them potentially useful measures of disease status.

Effect Evaluation of Biomedical Experiment Teaching Based on Intelligent Sensor

With the continuous development and progress of nanotechnology, its biosensors have been widely used in biomedical experimental teaching, and good experimental results have been achieved. Graphene, as a new nanomaterial with large surface area, good thermal conductivity, and unique electrical conductivity, has unique advantages in the field of biosensor preparation. Based on this, this paper will prepare the electrochemical sensor applied to biomedical experimental teaching based on graphene, optimize the detection sensitivity and detection range of graphene electrochemical sensor based on the corresponding experimental conditions, and improve its corresponding stability and reusability. At the level of electrochemical activity of biosensors, this paper innovatively uses the electric AC impedance method to detect the electrochemical activity, so as to accurately evaluate the key characteristics of biosensors. Based on the preparation of biosensors and the results of biological experiments, this paper will design a network-based biomedical experiment teaching effect evaluation system, and realize the basic functions of teacher-student interaction, teaching effect evaluation, sensor performance evaluation and so on. Based on the above, the electrochemical sensor based on graphene and a conductive polymer solution is actually prepared in this paper. At the same time, the electrocatalysis experiment is carried out based on the sensor, and the experimental teaching effect is systematically evaluated. The experimental results show that the sensitivity of the biosensor proposed in this paper is increased by about 10% compared with the traditional biosensor, the corresponding preparation complexity is reduced by nearly 1/3, and the corresponding reusability is increased by 30%. Therefore, the biomedical experiment teaching effect evaluation system proposed in this paper has good evaluation effect. It can provide accurate reference for the evaluation of biological experiment teaching effect, so it has important value and significance.

The effects of liraglutide on body composition and muscle strength in adult obese patients with type 2 diabetes mellitus

Objective: The aim of the present study was to observe the effects of liralutide on body composition and muscle function in adult obese patients with type 2 diabetes. Method: A total of 63 adult obese type 2 diabetic patients who were (52.6±9.7) years of age and with body mass index (BMI) of ≥28 kg/m2 were enrolled. The patients were randomly assigned into two groups. On the basis of maintaining the original hypoglycemic regimen, patients in the control group (n=24) were given dietary guidance only, and those in the treatment group (n=39) were injected with liraglutide. All patients were followed up for a period of 12 weeks. Blood glucose, glycosylated hemoglobin(HbA1c) and insulin levels, liver and kidney function, body composition assessed with electrical impedance methods, and grip strength measured by a grip meter for muscle function were detected at the baseline and the end of the study. Results: Compared with those in the control group, the reductions in HbA1c [(-1.54±2.10) % vs.(-0.53±0.84) %], body weight [(-3.46±4.2) kg vs.(-0.34±3.66) kg], body fat mass [(-1.97±2.98) kg vs.(-0.01±2.16) kg] and visceral fat area [(-0.01±2.16) cm2 vs.(0.34±6.39) cm2] were more pronouced in liraglutide treated group (all P<0.05). However, no changes could be observed in muscle mass and grip strength after liraglutide treatment. Conclusions: In addition to reducing blood glucose, body weight and fat mass, treatment with lilaluptide had no impact on muscle mass and muscle function. Therefore, liralutide is suitable for obese patients with type 2 diabetes, especially for weight management patients who are at risk of muscle loss.

Trends on New Cooperage Toasting/Charring Technology TCT. Radio Frequency Volumetric Heating and Infrared Surface Toasting Principles and Application: Influence on the Heartwood Composition and Quality

This paper addresses the problem of predicting soil properties using a combination of optical spectroscopic and electrical impedance methods. A comparative analysis between the most common machine learning methods such as Random Forest, Naive Bayes, Support Vector Machine, Decision Tree and Artificial Neural Network was performed using our research dataset consisting of 50 soil samples. The results indicate that none of the methods showed the best performance for nutrients prediction when only optical or electrical impedance spectroscopy measurements were used. Then, the influence of the principal components was validated to improve the machine learning performance. Their negative influence on the overall accuracy was found. Finally, the influence of the nutrient category on the prediction was validated, where similar results were found for 3-level grade and 5-level grade systems indicating a possibility for more precise and accurate soil characterization. In addition, the work shows the importance of repeated measurements for each soil sample, which can improve the overall accuracy.