Speed-resolved blood perfusion and oxygen saturation in human skin response to thermal stimulation

The functional status of vessels can be determined by assessing blood perfusion.By integrating diffuse reflectance spectroscopy(DRS)and Laser Doppler Flowmetry(LDF),the speed-resolved blood perfusion and blood oxygen saturation can be measured simultaneously by Enhanced Perfusion and Oxygen Saturation(EPOS).The dataset presented in this descriptor contains EPOS data recorded from a forearm point exposed to different levels of thermal stimulation,the classical LDF at control points,the R-R time series and data regarding the subjects’characteristics.All data were recorded from 60 recruited healthy subjects.Half of the subjects received different levels of thermal stimulation,and half of them were blank controls.We believe that this dataset will lead to the development of local blood perfusion methods that can be used to index vessel function assessments.This publicly available dataset will be beneficial to the microcirculation evaluation.

Correlation between Automated Quantification of Lung Perfusion Blood Volume (PBV) and Pulmonary Artery Pressure

Purpose: Dual-energy CT (DECT) can be used for quantification of lung perfusion blood volume (PBV), allowing objective evaluation. However, no reports have investigated pulmonary perfusion correlating with pulmonary artery pressure (PAP) in patients with chronic pulmonary diseases. The purpose was to evaluate automated quantification of the lung PBV using dual-energy CT, and its correlation with PAP. Methods: 274 patients who underwent echocardiography within two weeks also underwent CT. The population was divided into high (&ge;40 mmHg) and low (<40 mmHg) estimated systolic PAP (sPAP) groups (n = 63 and n = 211, respectively). We retrospectively eva-luated the lung PBV using Syngo software, and correlations between the lung PBV and estimated sPAP. Results: Lung PBV values were 25.0 ± 9.6 and 29.0 ± 9.3 Hounsfield units (HU) in high and low sPAP groups, respectively, with a significant difference between them (p = 0.003). In the high sPAP group with underlying lung diseases (n = 15), chronic thromboembolism (n = 25), pulmonary artery stenosis (n = 12), and left heart failure (n = 11), using the Dana Point classification system, lung PBV values were 18.6 ± 1.6, 25.1 ± 4.5, 25.8 ± 4.5, and 32.7 ± 9.4 HU, respectively. There were significant differences in quantification of the lung PBV among them. The mean sPAP of subjects with left heart failure was significantly higher than in the others. In subjects with left heart failure, a positive correlation between the lung PBV value and sPAP was noted (R = 0.721, p < 0.0001). Conclusions: Automated quantification of the lung PBV may estimate the high sPAP. The lung PBV may contribute to clarifying the etiology of a high PAP due to left heart failure.

Choroidal blood perfusion as a potential"rapid predictive index"for myopia development and progression

Myopia is the leading cause of visual impairment worldwide.The lack of a"rapid predictive index"for myopia development and progression hinders the clinic management and prevention of myopia.This article reviews the studies describing changes that occur in the choroid during myopia development and proposes that it is possible to detect myopia development at an earlier stage than is currently possible in a clinical setting using choroidal blood perfusion as a"rapid predictive index"of myopia.

Extraction method of nanoparticles concentration distribution from magnetic particle image and its application in thermal damage of magnetic hyperthermia

Magnetic particle imaging(MPI)technology can generate a real-time magnetic nanoparticle(MNP)distribution image for biological tissues,and its use can overcome the limitations imposed in magnetic hyperthermia treatments by the unpredictable MNP distribution after the intratumoral injection of nanofluid.However,the MNP concentration distribution is generally difficult to be extracted from MPI images.This study proposes an approach to extract the corresponding concentration value of each pixel from an MPI image by a least squares method(LSM),which is then translated as MNP concentration distribution by an interpolation function.The resulting MPI-based concentration distribution is used to evaluate the treatment effect and the results are compared with the ones of two baseline cases under the same dose:uniform distribution and MPI-based distribution considering diffusion.Additionally,the treatment effect for all these cases is affected by the blood perfusion rate,which is also investigated deeply in this study.The results demonstrate that the proposed method can be used to effectively reconstruct the concentration distribution from MPI images,and that the weighted LSM considering a quartic polynomial for interpolation provides the best results with respect to other cases considered.Furthermore,the results show that the uniformity of MNP distribution has a positive correlation with both therapeutic temperature distribution and thermal damage degree for the same dose and a critical power dissipation value in the MNPs.The MNPs uniformity inside biological tissue can be improved by the diffusion behavior after the nanofluid injection,which can ultimately reflect as an improvement of treatment effect.In addition,the blood perfusion rate considering local temperature can have a positive effect on the treatment compared to the case which considers a constant value during magnetic hyperthermia.

A harmonic-wave bio-thermal method for continuous monitoring skin thermal conductivity and capillary perfusion rate

The revelation of thermal energy exchange mechanism of human body is challenging yet worthwhile,because it can clearly explain the changes in human symptoms and health status.Understanding,the heat transfer of the skin is significant because the skin is the foremost organ for the energy exchange between the human body and the environment.In order to diagnose the physiological conditions of human skin without causing any damage,it is necessary to use a non-invasive measurement technique by means of a conformal flexible sensor.The harmonic method can minimize the thermal-induced injury to the skin due to its low heat generating properties.A novel type of computational theory assessing skin thermal conductivity,blood perfusion rate of capillaries in the dermis,and superficial subcutaneous tissues was formed by combining the multi-medium thermal diffusion model and the bio-thermal model(Pennes equation).The skins of the hand back of six healthy subjects were measured.It was found that the results revealed no consistent changes in thermal conductivity were observed across genders and ages.The measured blood perfusion rates were within the range of human capillary flow.It was found that female subjects had a higher perfusion rate range(0.0058-0.0061 s^(-1))than male subjects(0.0032-0.0049 s^(-1)),which is consistent with invasive medical studies about the gender difference in blood flow rates and stimulated effects in relaxation situations.

Wet Cupping Therapy Improves Local Blood Perfusion and Analgesic Effects in Patients with Nerve-Root Type Cervical Spondylosis

Objective： To observe wet cupping therapy（WCT） on local blood perfusion and analgesic effects in patients with nerve-root type cervical spondylosis（NT-CS）. Methods： Fifty-seven NT-CS patients were randomly divided into WCT group and Jiaji acupoint-acupuncture（JA） group according a random number table. WCT group（30 cases） was treated with WCT for 10 min, and JA group（27 cases） was treated with acupuncture for 10 min. The treatment efficacies were evaluated with a Visual Analogue Scale（VAS）. Blood perfusion at Dazhui（GV 14） and Jianjing（GB 21） acupoints（affected side） was observed with a laser speckle flowmetry, and its variations before and after treatment in both groups were compared as well. Results： In both groups, the VAS scores significantly decreased after the intervention（P〈0.01）, while the blood perfusion at the two acupoints significantly increased after intervention（P〈0.05）; however, the increasement magnitude caused by WCT was obvious compared with JA（P〈0.05）. Conclusion： WCT could improve analgesic effects in patients with NT-CS, which might be related to increasing local blood perfusion of acupunct points.

Choroidal blood perfusion as a potential“rapid predictive index”for myopia development and progression

Myopia is the leading cause of visual impairment worldwide.The lack of a“rapid predictive index”for myopia development and progression hinders the clinic management and prevention of myopia.This article reviews the studies describing changes that occur in the choroid during myopia development and proposes that it is possible to detect myopia development at an earlier stage than is currently possible in a clinical setting using choroidal blood perfusion as a“rapid predictive index”of myopia.

Dynamic changes of renal cortical blood perfusion before and after percutaneous transluminal renal artery stenting in patients with severe atherosclerotic renal artery stenosis

Background:This study aims to observe the dynamic changes of renal artery(RA)disease and cortical blood perfusion(CBP)evaluated by contrast-enhanced ultrasound(CEUS)after percutaneous transluminal renal artery stenting(PTRAS)in patients with severe atherosclerotic renal artery stenosis(ARAS)and to analyze the relationship between CBP and prognosis.Methods:This was a single-center retrospective cohort study.A total of 98 patients with unilateral severe ARAS after successful PTRAS in Beijing Hospital from September 2017 to September 2020 were included.According to renal glomerular filtration rate(GFR)detected by radionuclide imaging at 12 months after PTRAS,all patients were divided into the poor prognosis group(n=21,GFR decreased by≥20%compared with baseline)and the control group(n=77,GFR decreased by<20%or improved compared with baseline).Renal artery stenosis was diagnosed by digital subtraction angiography,and renal CBP was evaluated by CEUS using TomTec Imaging Systems(Germany)before PTRAS,at 6 months and 12 months after discharge.The receiver operating characteristic(ROC)curve with area under the curve(AUC)was used to analyze the predictive value of CBP parameters,including area under ascending curve(AUC1),area under the descending curve(AUC2),rising time(RT),time to peak intensity(TTP),maximum intensity(IMAX),and mean transit time(MTT)for poor prognosis.Results:Among the 98 patients,there were 52 males(53.1%),aged 55–74 years old,with an average age of 62.1±8.7 years,and an average artery stenosis of 82.3±12.9%.The poor prognosis group was associated with significantly increased incidence of diabetes(76.2%vs.41.6%),and lower levels of GFR of the stenotic kidney(21.8 mL/min vs.25.0 mL/min)and total GFR(57.6 mL/min vs.63.7 mL/min)(all P<0.05),compared with the control group(P<0.05).In addition,the rate of RA restenosis was significantly higher in the poor prognosis group than in the control group(9.5%vs.0,χ^(2)=9.462,P=0.002).Compared with the control group,the poor prognosis group was associated with significantly decreased baseline AUC1 and AUC2,and extended duration of TTP and MTT(P<0.05).At 6 months and 12 months of follow-up,patients in the control group were associated with markedly increased AUC1,AUC2,and IMAX,and shorter duration of RT and MTT(P<0.05).The ROC curve showed that the predictive values of AUC1,AUC2,RT,TTP,IMAX,and MTT for poor prognosis were 0.812(95%CI:0.698–0.945),0.752(95%CI:0.591–0.957),0.724(95%CI:0.569–0.961),0.720(95%CI:0.522–0.993),0.693(95%CI:0.507–0.947),and 0.786(95%CI:0.631–0.979),respectively.Conclusions:Preoperative renal CBP in severe ARAS patients with poor prognosis is significantly reduced,and does not show significant improvement after stent treatment over the first year of follow-up.The parameter AUC1 may be a good predictor for renal dysfunction after PTRAS in severe ARAS patients.Trial Registration:ChiCTR.org.cn,ChiCTR1800016252.

Investigation of a spherical-section ultrasound phased array for hepatic ablation

A 3D ultrasound thermal model with a 3D finite element representation for modeling the thermal diffusion effects for hepatic ablation induced by spherical-section ultrasound phased array was developed. The model was first validated against available published measured data in rat liver. Using the validated model,effects of blood perfusion and heating schemes on lesion formation were studied for both single focus and split-focus intensity patterns. It was shown that for single focus sonication pattern the short-duration(～2 s) and high-intensity(～1250 W/cm2) heating scheme can completely reduce the cooling effect of the blood perfusion. The lesion shape and size were significantly altered by perfusion for split-focus pattern even with a rapid heating scheme when the focus spacing was larger than 2.4 mm. Underdosed areas might be present between two foci. Prolonging ex-posure time or shortening focus spacing can reduce the cool region between two foci. In addition,the influences of thermal and acoustic parameters were also studied. When the therapy depth is short(<5 cm) ,the lesion size monotonically increases with increasing attenuation coefficient that ranges from 5.4 to 11 Np/(m?MHz) .

Effects of Different Scraping Techniques on Body Surface Blood Perfusion Volume and Local Skin Temperature of Healthy Subjects

Objective: To study the mechanism and effects of different scraping techniques on body surface blood perfusion volume and local skin temperature of healthy subjects and to provide a baseline for microcirculation and energy metabolism for the evaluation of the therapeutic effects of scraping. Methods: Changes of the local blood perfusion volume and skin temperature of healthy subjects before and after applying different scraping techniques were observed with a laser Doppler imager combined with an infrared thermographic device and the resulting data was analyzed with imaging and processing software for statistical analysis. Results: Local blood perfusion volume and skin temperature all increased after both reinforcing and reducing scraping techniques. The value of blood flow 60 and 90 min after the reducing technique was significantly higher than that after the reinforcing technique (P<0.01), while the skin temperature increased after both techniques but was not significantly different between the two (P>0.05). Conclusion: Scraping can significantly improve the local blood perfusion volume, increase skin temperature and promote local blood circulation and metabolism of tissues.

Impact of primary percutaneous coronary intervention on blood perfusion in nonculprit artery in patients with anterior ST elevation myocardial infarction

Background Recent studies have demonstrated that epicardial flow in nonculprit arteries, which has been assumed to be normal, was slowed in the setting of ST-elevation myocardial infarction （STEMI）. However, the impact of primary percutaneous coronary intervention （PCI） on blood perfusion in nonculprit arteries in patients with STEMI has not been clarified. The purpose of this study was to investigate the impact of primary PCI on blood perfusion in nonculprit arteries in patients with STEMI and correlated clinical factors. Methods A total of 117 patients with anterior wall STEMI, the culprit artery being the left anterior descending artery （LAD）, undergoing primary PCI （the study group） and 100 patients with normal coronary angiography （the control group） were enrolled. To observe the differences of corrected TIMI frame count （cTFC） and myocardial blush grade （MBG） before and after primary PCI in both culprit and nonculprit arteries, the left circumflex coronary artery （LCX）, cTFC and MBG in the LAD and LCX were measured in the study group and control group. The study group was divided into three groups; refiow in the culprit artery group （the R group）, no reflow in culprit artery group （the NR group）, and no reflow in both the culprit artery and nonculprit artery group （the NRB group） according to MBG grade. The level of serum C-reactive protein （CRP）, catecholamine, and fibroblast growth factor-21 （FGF21）were assayed. The clinical and angiographic characteristics were also analyzed. Results cTFC （28.1±24.3 vs. 20.3±19.3, P 〈0.05） and MBG in the LCX were different in the study group compared to the control group before primary PCI. cTFC （25.2±22.3 vs. 28.1±24.3, P 〈0.05） and the MBG level in the LCX were improved after successful primary PCI, but were not recovered to the normal level. Patients with no reflow in the culprit artery had a higher incidence of no-reflow in the nonculprit artery （78% vs. 19%, P 〈0.0001）, and the levels of CRP （（3.29±1.31） mg/dl vs. （2.51±1.14） mg/dl vs. （2.93±1.07） mg/dl, P 〈0.05, respectively）, catecholamine （（epinephrine （693.48±89.78） pg/ml vs. （398.12±93.28） pg/ml vs. （562.54±96.22） pg/ml, P 〈0.0001, respectively）, and norepinephrine （（7012.43±932.47） pg/ml vs. （4012.34±814.16） pg/ml vs. （5549.03＋912.65） pg/ml, P 〈0.0001, respectively））in the NRB group were higher than those in the R group and NR group. The level of FGF21 （（0.299±0.093） ng/ml vs. （0.612±0.071） ng/ml vs. （0.428±0.074） ng/ml, P 〈0.0001 respectively） in the NRB group was lower than that in the R group and NR group. Conclusions The blood perfusion in the nonculprit artery may be impaired in patients with STEMI. Although nonculprit artery perfusion may be improved after successful primary PCI, it is still lower than that in the control group, and may be involved in inflammation and spasms.

Application of Thermal Science to Tongue Inspection in Traditional Chinese Medicine

The study on Traditional Chinese Medicine (TCM)by the technology and method of thermal science is a new cut in point in interdisciplinary science, and its purpose is to study the tongue inspection in TCM from the view of the bio heat transfer theory. In this paper human tongues were studied with the infrared thermal imaging technology. And the characteristic relationship between temperature distribution and age, tongue color as well as infrared thermal tongue image concerning the characteristic of viscera was analyzed by the experimental data,which confirms that the change in temperature distribution in different positions of the tongue is related to the diseases of different internal organs of the body. From a series of invasive experiments in animals, the blood perfusion rate was measured with the equipment of CBI 8000 Doppler Blood Flow Meter and MP 100 Physiologic Research System for the first time and the characteristic relationship curve between the temperature on the surface of the tongue and the blood perfusion rate was obtained. From the experiments the temperature on the surface of the tongue reflects objectively the tongue color which is influenced by the blood perfusion rate. This will help to develop some new cognition in the theory of TCM.

Study on correlation between pathology and the contrast-enhanced ultrasound characteristics of primary liver cancer

Objective:The aim of this study was to evaluate the value of contrast-enhanced ultrasound(CEUS) for blood perfusion of primary liver cancer(PHC) and investigate the correlation between microvascular architecture of PHC and pathological differentiation.Methods:Two hundred and seventy-eight patients with 329 PHC lesions were examined by CEUS and analysised the contrast enhancement pattern and correlation with pathology.Results:1.CEUS patterns of PHC:71.7%(236/329) showed "swift enhancement in the arterial phase and swift expurgation in the portal phase",13.4%(44/329) for as "swift enhancement and slow expurgation",7.3%(24/329) as "swift enhancement and simultaneity expurgation",4.3%(14/329) for the "slow enhancement and swift expurgation",2.1%(7/329) as "slow enhancement and expurgation",1.2%(4/329) as "not fast forward".2.90.3%(297/329) of PHC lesions were hypervascular liver cancer and 9.7%(32/329) were hypovascular.Hepatocellular carcinoma(HCC) were hypervascular lesions and intrahepatic cholangiocarcinoma(ICC) were hypovascular lesions.3.PHC size had a significant difference on the contrast media purfusion pattern(P < 0.05),but not on the contrast media expurgation pattern.4.The accuracy of PHC by CEUS were 97.3% and compared to pathology,9 lesions of PHC were misdiagnosed.Conclusion:CEUS can show the different blood perfusion characteristics of PHC with closely related to pathological differentiation,which be valuable to diagnose liver cancer.

Clinical and Experimental Study on Effect of Rhubarb on Gastrointestinal Blood Flow Perfusion

Objective: To study the effect of rhubarb on gastrointestinal (GI) blood flow perfussion. Methods: State of GI blood flow perfussion in critically illed patients was estimated by intramural pH (pHi) of GI to observe the clinical effect of rhubarb on it, and experimental study was performed in hemorrhagic shocked rats. Results: Clinical study showed pHi level in septic patients was much lower than that in the control, whereas rhubarb could obviously elevate it (P<0.001). The clinical effective rate of rhubarb in treating stress ulcer caused hemorrhage was 73%. Animal study showed that though the shocked rats were resuscitated completely, their GI blood flow perfussion was much lower than that in the control. Rhubarb could significantly improve the blood perfusion of mucous membrane of GI and mesenterium (P<0.01) in shocked or normal rats. Conclusion: Rhubarb could improve the GI blood perfussion in critical illness and shocked rats.

A Surface Heat Disturbance Method for Measuring Local Tissue Blood Perfusion Rate

A non-damage method for measuring local tissue blood perfusion rate by surface heat disturbance and its two special embodiments for realizing this measurement are presented in this paper.In the derivation of mathematical model,the Pennes equation is used, and two parameters which are very difficult to be known-the arterial blood temperature Tαand the metabolic heat generation rate qm,have been eliminated.So it has provided a feasible basis for application.In this paper,the performance and the adaptable condition of the measurement method and its structure peculiarities are discussed over a wide variety of parameters.Moreover,the effectiveness of the measurement method has been demonstrated by means of the quantitative measurement of tissue in vitro,the comparative measurement of animal under artificial perfusion and the dependence measurement in human body.

Physical exercise suppresses hepatocellular carcinoma progression by alleviating hypoxia and attenuating cancer stemness through the Akt/GSK-3β/β-catenin pathway

Objective:Physical exercise,a common non-drug intervention,is an important strategy in cancer treatment,including hepatocellular carcinoma(HCC).However,the mechanism remains largely unknown.Due to the importance of hypoxia and cancer stemness in the development of HCC,the present study investigated whether the anti-HCC effect of physical exercise is related to its suppression on hypoxia and cancer stemness.Methods:A physical exercise intervention of swimming(30 min/d,5 d/week,for 4 weeks)was administered to BALB/c nude mice bearing subcutaneous human HCC tumor.The anti-HCC effect of swimming was assessed in vivo by tumor weight monitoring,hematoxylin and eosin(HE)staining,and immunohistochemistry(IHC)detection of proliferating cell nuclear antigen(PCNA)and Ki67.The expression of stemness transcription factors,including Nanog homeobox(NANOG),octamer-binding transcription factor 4(OCT-4),v-Myc avian myelocytomatosis viral oncogene homolog(C-MYC)and hypoxia-inducible factor-1a(HIF-1a),was detected using real-time reverse transcription polymerase chain reaction.A hypoxia probe was used to explore the intratumoral hypoxia status.Western blot was used to detect the expression of HIF-1a and proteins related to protein kinase B(Akt)/glycogen synthase kinase-3β(GSK-3β)/β-catenin signaling pathway.The IHC analysis of platelet endothelial cell adhesion molecule-1(CD31),and the immunofluorescence co-location of CD31 and desmin were used to analyze tumor blood perfusion.SMMC-7721 cells were treated with nude mice serum.The inhibition effect on cancer stemness in vitro was detected using suspension sphere experiments and the expression of stemness transcription factors.The hypoxia status was inferred by measuring the protein and mRNA levels of HIF-1a.Further,the expression of proteins related to Akt/GSK-3β/β-catenin signaling pathway was detected.Results:Swimming significantly reduced the body weight and tumor weight in nude mice bearing HCC tumor.HE staining and IHC results showed a lower necrotic area ratio as well as fewer PCNA or Ki67 positive cells in mice receiving the swimming intervention.Swimming potently alleviated the intratumoral hypoxia,attenuated the cancer stemness,and inhibited the Akt/GSK-3β/β-catenin signaling pathway.Additionally,the desmin+/CD31+ratio,rather than the number of CD31+vessels,was significantly increased in swimming-treated mice.In vitro experiments showed that treating cells with the serum from the swimming intervention mice significantly reduced the formation of SMMC-7721 cell suspension sphere,as well as the m RNA expression level of stemness transcription factors.Consistent with the in vivo results,HIF-1a and Akt/GSK-3β/β-catenin signaling pathway were also inhibited in cells treated with serum from swimming group.Conclusion:Swimming alleviated hypoxia and attenuated cancer stemness in HCC,through suppression of the Akt/GSK-3β/β-catenin signaling pathway.The alleviation of intratumoral hypoxia was related to the increase in blood perfusion in the tumor.

Acupuncture Enhances Signalsat Sensitized Acupoints to Elevate Pressure Pain Thresholdin Knee Osteoarthritis Patients

Objective:To observe the pressure pain threshold(PPT),skin conductance(SC)and blood perfusion(BP)of the sensitized acupoints in patients with knee osteoarthritis(KOA),and explore the mechanism of acupuncture at the sensitized acupoints for treating diseases.Methods:Eleven healthy subjects and 11 unilateral KOA patients were recruited from July 2020 to March 2021 in this study.The PPT,SC and BP of control acupoints in healthy controls,and non-sensitized and sensitized acupoints in KOA patients were measured and compared between baseline and after manual acupuncture(MA)treatment.Results:Before MA treatment,lower PPT was observed at the sensitized acupoints comparedwith non-sensitized andcontrol acupoints(P<0.05).After MA treatment,PPT at the sensitized acupoints increased significantly in KOA patients(P<0.05).Before MA treatment,there was no statistical difference in SC and BP among control,non-sensitized and sensitized acupoints(P>0.05).Compared with the control and non-sensitized acupoints,there were significant increases of SC and BP in sensitized acupoints of KOA patients after MA treatment(P<0.05 or P<0.01).Conclusion:MA at sensitized acupoints could elevate PPT of KOA patients,which may be associated with the increment of SC and BP.

Thermodynamic Significance of Human Basal Metabolism

The human basal state,a non-equilibrium steady state,is analysed in this paper in the light of the First and Second Laws of Thermodynamics whereby the thermodynamic significance of the basal metabolic rate and its distinction to the dissipation function and exergy loss are identified.The analysis demonstrates the correct expression of the effects of the blood flow on the heat balance in a human-body bio-heat model and the relationship between the basal metabolic rate and the blood perfusion.

ANALYTICAL SOLUTIONS OF NON-FOURIER PENNES AND CHEN-HOLMES EQUATIONS

The analytical solutions of non-Fourier Pennes and Chen Holmes equations are obtained using the Laplace transformation and particular solution method in the present paper. As an application, the effects of the thermal relaxation time % the blood perfusion wb, and the blood flow velocity v on the biological skin and inner tissue temperature T are stxldied in detail The results obtained in this study provide a good alternative method to study the bio-heat and a biophysical insight into the understanding of the heat transfer in the biotissue.