Plantar pressure distribution can reflect the force of several key points on foot while standing and walking. A comprehensive understanding of the plantar pressure distribution makes great sense in the following aspects:the understanding of the normal foot biomechanics and function, clinical diagnosis, measurement of disease extent, postoperative efficacy evaluation, and rehabilitation research. A simple plantar pressure measurement device was designed in this study. This paper uses FlexiForce flexible sensor to pickup plantar pressure signal and USB A/D board to do data acquisition. The data are transferred into a laptop and processed by a VB-based software which can display, remember and replay the data. We chose patients with hallux valgus and normal people to measure the pressure distribution and make contrast analysis of plantar pressure with this device. It can be concluded that people with hallux valgus have higher pressure on the second metatarsophalangeal joint and the distribution move outward. The plantar pressure of patients postoperative could be greatly improved compared to the preoperative. The function of this device has been confirmed.
Objective To systematically review the effectiveness of forced air warming for the maintenance of perioperative core temperature, so as to provide clinical evidence for an appropriate warming plan during the perioperative period. Methods We electronically searched PubMed, The Cochrane Library, EMbase, Web of Science, CBM and CNKI from 2000 to 2012, so as to comprehensively collect randomized controlled trials (RCTs) about the effectiveness of different warming methods for the maintenance of perioperative core temperature (including forced air warming, resistive-heating blanket/electric heating pad, circulating water mattress, and infrared ray radiant heating system) for maintenance of perioperative core temperature. References of the included studies were also retrieved. Two reviewers independently screened literature according to the inclusion and exclusion criteria, extracted data and assessed the quality of the included studies. Then, meta-analysis was performed using RevMan 5.1 software. Results Eleven RCTs involving 577 patients were included. The results of meta-analysis indicated that, in the maintenance of core temperature during the perioperative period, forced air warming was superior to resistive-heating blanket/electric heating pad (SMD= –0.40, 95%CI –0.73 to –0.06), circulating water mattress (SMD= –1.10, 95%CI –1.55 to –0.66), and infrared ray radiant heating system (SMD= –0.69, 95%CI –1.06 to –0.32). In the incidence of hypothermia during the perioperative period, the group of forced air warming was lower than the group of blanket/electric heating pad (RR=1.76, 95%CI 1.15 to 2.69), but it was the same as the group of infrared ray radiant heating system (RR=1.37, 95%CI 0.83 to 2.27). In the incidence of shivering during the perioperative period, the group of forced air warming was the same as the group of blanket/electric heating pad (RR=0.75, 95%CI 0.18 to 3.21) and the group of infrared ray radiant heating system (RR=0.8, 95%CI 0.19 to 3.36). Conclusion Compared with resistive-heating blanket/electric heating pad, circulating water mattress, and infrared ray radiant heating system, forced air warming maintains patients’ core temperature better during the perioperative period, with a lower incidences of hypothermia. Due to the limited quantity and quality of the included studies, more high quality RCTs with large sample size are needed to verify the above conclusion.
Objective To study the influence of in vitro force-vascularization on in vivo vascularization of porous polylactic glycolic acid copolymer(PLGA) scaffolds with internal network channels (PPSINC). Methods After the in vitro forcevascula ization of PPSINCs covered with microvessel endothelial cells (MVEC) of mice, they were divided into two groups: the force-vascularization group (group A) and the control group with only PSINCs (group B). All the PPSINCs were planted in the mesentery of 12 mice for 2 and 4 weeks, the PPSINCs were cut out, the vascular ization of PPSINCs was investigated by histology and immunohistochemistry, and the vascularization area of the histologic section of the PPSINCswas measured with the computer-assistant image analysis system. Result After the in vitro forcevascularization of PPSINCs, the MVEC of the mice sticking on the channel wall could be seen. After the scaffold was im planted into the mice for 2 weeks, the vascularization area of the histologic section of PPSINCs (VA) in group A (2 260.91±242.35 μm2) was compared with that in group B (823.64±81.29 μm2)，and the difference was sig nificant in statistics（P＜0.01).The VA for 4 weeks in group A (17 284.36 ±72.67 μm2) was compared with that in group B (17 041.14±81.51 μm2), and the difference was not significant in statistics（P＞0.05）.The area of the actin positivestaining (AA) in the histologi c section of PPSINCs for 2 weeks’ implantation in group A (565.22±60.58 μm2) was compared with that in group B (205.91±16.25 μm2), and the difference was signi ficant in statistics（P＜0.01). After the implantation for 4 weeks, the VA in group A (4 321.09±19.82 μm2) was compared with group B (4 260.28±27.17 μm2), and the difference was not significant in statistics（P＞0.05）. Conclusion The PPSINC is a good simple scaffold model of vasculariazation. The in vitro force-vascularization can increase the in vivo vascularization of PPSINCs in the early stage.
Respiratory oscillometry is a lung function test that measures the mechanical properties of respiratory system by the forced oscillation technique. Oscillometry can be used in those who cannot perform traditional lung function tests, including young children. It is also an important tool to assess small airways function in clinical and research fields. In 2020, the European Respiratory Society published a new technical standard for respiratory oscillometry, which offered updated technical recommendations on the hardware, software, testing protocols and quality control of oscillometry measurements. This paper interpreted the new technical standard, for providing technical suggestions regarding oscillometry measurements in clinical and research settings, and as a reference for developing technical statements and recommendations for oscillometry in China.
To address the challenges of capturing micro-strains in detecting esophageal motility disorders and the limitations of existing high-resolution manometry and functional intraluminal imaging probes in directly measuring esophageal tissue electrical impedance, this study proposes a novel flexible balloon sensor structure that integrates a piezoelectric film assembly with a distributed impedance electrode array. Using the electrical analysis module in the finite element analysis (FEA) software, simulations of the forward problem for esophageal impedance detection were conducted to optimize the excitation source parameters, and a physical prototype was fabricated. Under a relative excitation mode with a voltage sensitivity of 2.059%, the voltage output characteristics of the impedance electrode array were analyzed during linear changes in the balloon filling volume. Based on the performance variation of the piezoelectric film assembly, 80% was selected as the optimal filling volume. Force-electric coupling tests were conducted on the balloon sensor using a pressure testing platform, revealing that both the piezoelectric film assembly inside the balloon and the impedance electrodes outside the balloon exhibited significant load differentiation characteristics as the force application point shifted. In summary, this balloon sensor facilitates the localization of force application while simultaneously analyzing esophageal tissue properties, offering a novel diagnostic approach and objective tool for esophageal disease detection.
Objective
Since 2009, assessment of asthma control in Global Initiative for Asthma (GINA) includes current clinical control and future risk. " Current clinical control” is replaced by " symptom control” in GINA 2015, and lung function is excluded from assessment of current clinical control. This study was designed to investigate the agreement in current asthma control assessment between GINA 2009 and 2015, and to explore whether FEV1 monitoring plays an important role in this context.
Methods
A cross-sectional study was conducted among patients with stable asthma (n=138). The levels of asthma control were graded by GINA 2009 and GINA 2015, respectively. Demographic data, spirometry, exacerbations in the past 12 months, peripheral blood cells, induced sputum were collected. Kappa coefficient was used to measure the agreement of the two asthma control tools. Association of the asthma control levels using the two tools with the exacerbations in the past 12 months was examined by Spearman correlations. Additionally, associations of lung function with the exacerbations in the past 12 months were analyzed.
Results
Agreement in assessing current asthma control between GINA 2009 and 2015 was moderate (Kappa=0.595, P<0.001). Compared with GINA 2009, the patients with well-controlled asthma assessed by GINA 2015 had worse FEV1%pred [(89.9±12.9)% vs. (79.9±18.2)%, P=0.013], the partly controlled subjects assessed by GINA 2015 had worse asthma control scores in ACQ-6 score (0.8±0.7 vs. 1.1±0.7, P=0.028) and ACT score (20.7±2.5 vs. 19.4±2.5, P=0.007). Furthermore, asthma control levels assessed by either GINA 2015 or 2009 were related to exacerbations in the past 12 months and stronger relationship was presented in GINA 2015 (r=–0.268 for GINA 2015 vs. r=–0.212 for GINA 2009, respectively). In addition, there were no differences in cell counts in induced sputum or peripheral blood or IgE level in peripheral blood in patients with different asthma control levels assessing by GINA 2009 and 2015.
Conclusions
Our study indicates that it has a moderate agreement of assessing current asthma control between GINA 2015 and 2009. Compared with GINA 2009, absence of FEV1 monitoring from GINA 2015 would result in worse lung function in well-controlled asthma and worse asthma control scores in partly controlled asthma. Addition of FEV1 monitoring to GINA 2015 would weaken the relationship between current asthma control and future asthma outcomes, although it didn't reach statistical significance. Our study supports that GINA 2015 lacking lung function monitoring in current asthma control assessment is applicable in clinical practice.
Objective To establish amedical reference for adult pulmonary function parameters and a normal FEV1 /FVC% pred in population of Shanghai. Methods Subjects who underwent routine physical examination were initially screened and those who met enrollment criteria with age over 18 years old were required to underwent pulmonary function tests in Zhongshan Hospital from June 2009 to February 2010. After screening of 450 subjects, a total of 240 subjects with normal pulmonary function and 120 subjects with mild small airway abnormalities were enrolled in this study according to the prediction equations established in1988. All subjects were assigned into 6 groups according to their age with30 males amd 30 females in each group. Pulmonary function parameters including VC, FVC, FEV1 , FEV1 /FVC, PEF, FEF25% , FEF50% , FEF75% , RV, FRC, TLC, RV /TLC, DLCO, and KCO were collected for analysis. New prediction equations for the above 14 parameters were established by parameters of anthropometry. The medical reference ranges of 14 parameters were calculated according to the newprediction equations. The normal FEV1 /FVC%pred was also calculated. Results New prediction equations for normal adult pulmonary function parameters in Shanghai were established. DLCO =5.206 +4. 314 ×gender ( “male”= 1, “female”=0) - 0. 144 ×age( y) +0. 098 × height( cm) +0. 082 ×weight( kg) , KCO =9. 346 - 0. 026 ×age( y) - 0. 031 ×height( cm) +0. 025 ×weight( kg) .The LLN( P5) of VC, FVC, FEV1 , FEV1 /FVC, the LLN( P2. 5 ) and the upper limit of normal value ( P97. 5) of FRC, TLC, RV, RV/TLC were calculated. The LLN( P5) of FEV1 /FVC = 101. 924 - 0. 144 × age ( y) - 0. 118 ×high( cm) . The lower normal limit of FEV1 /FVC% pred was 92% . Conclusions This is the first time to have the medical reference of FEV1 /FVC% pred in China, and new prediction equations for DLCO in Shanghai. The LLN of FEV1 /FVC or FEV1 /FVC% pred lt;92% can be used as diagnostic criteria for obstructive ventilation disorder. Instead of using FEV1% pred lt; 80% , FEV1 lt; LLN can be used as diagnostic criteria for mild ventilation disorder.
Objective To observe the decline ratio of FEV1 after inhaling 0. 9% saline to the baseline, and to explore its relation to the result of bronchial provocation test ( BPT) with methacholine.Methods 115 patients with chronic cough or chest tightness were collected in Shougang Hospital, Peking University from March 2008 to September 2009. They were all performed pulmonary function test and the decline ratio of FEV1 after inhaling 0.9% saline to the baseline( ΔFEV1 ) was measured. Then they were allperformed BPT with methacholine. The predictive value of ΔFEV1 measurement for BPT results was evaluated. Results 49 cases yielded positive results in methacholine BPT, with ΔFEV1 gt; 3% in 35 cases and gt;5% in 20 cases. 66 casess yielded negative results in methacholine BPT, with ΔFEV1 gt; 3% in 6 cases. The sensitivity and specificity were 71% and 91% respectively when ΔFEV1 gt;3% was set as a cutoff,and which were 40. 8% and 100% respectively when ΔFEV1 gt;5% was set as a cut-off. All the patients didn’t show any serious adverse reaction. Conclusion ΔFEV1 gt;3% after inhaling 0. 9% saline is a good predictor for BPT results. More caution should be paid to these patients when performing BPT.
In resting platelets, the 17th domain of filamin a (FLNa17) constitutively binds to the platelet membrane glycoprotein Ibα (GPIbα) at its cytoplasmic tail (GPIbα-CT) and inhibits the downstream signal activation, while the binding of ligand and blood shear force can activate platelets. To imitate the pull force transmitted from the extracellular ligand of GPIbα and the lateral tension from platelet cytoskeleton deformation, two pulling modes were applied on the GPIbα-CT/FLNa17 complex, and the molecular dynamics simulation method was used to explore the mechanical regulation on the affinity and mechanical stability of the complex. In this study, at first, nine pairs of key hydrogen bonds on the interface between GPIbα-CT and FLNa17 were identified, which was the basis for maintaining the complex structural stability. Secondly, it was found that these hydrogen bonding networks would be broken down and lead to the dissociation of FLNa17 from GPIbα-CT only under the axial pull force; but, under the lateral tension, the secondary structures at both terminals of FLNa17 would unfold to protect the interface of the GPIbα-CT/FLNa17 complex from mechanical damage. In the range of 0~40 pN, the increase of pull force promoted outward-rotation of the nitrogen atom of the 563rd phenylalanine (PHE563-N) at GPIbα-CT and the dissociation of the complex. This study for the first time revealed that the extracellular ligand-transmitted axial force could more effectively relieve the inhibition of FLNa17 on the downstream signal of GPIbα than pure mechanical tension at the atomic level, and would be useful for further understanding the platelet intracellular force-regulated signal pathway.
Currently, transcranial magnetic stimulation (TMS) has been widely used in the treatment of depression, Parkinson’s disease and other neurological diseases. To be able to monitor the brain’s internal activity during TMS in real time and achieve better treatment outcomes, the researchers proposed combining TMS with neuroimaging methods such as magnetic resonance imaging (MRI), both of which use Tesla-level magnetic fields. However, the combination of strong current, large magnetic field and small size is likely to bring physical concerns which can lead to mechanical and thermal instability. In this paper, the MRI static magnetic field, the TMS coil and human head model were built according to the actual situations. Through the coupling of the magnetic field and the heat transfer module in the finite element simulation software COMSOL, the force and temperature of the TMS coil and head were obtained when the TMS was used in combination with MRI (TMS-MRI technology). The results showed that in a 3 T MRI environment, the maximum force density on the coil could reach 2.51 × 109 N/m3. Both the direction of the external magnetic field and the current direction in the coil affected the force distributions. The closer to the boundary of the external magnetic field, the greater the force. The magnetic field generated by the coil during TMS treatment increased the temperature of the brain tissue by about 0.16 °C, and the presence of the MRI static magnetic field did not cause additional thermal effects. The results of this paper can provide a reference for the development of the use guidelines and safety guidelines of TMS-MRI technology.
