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Resumo Fundamento A rigidez arterial pode afetar diretamente os rins, que são perfundidos passivamente por alto fluxo. No entanto, determinar se a relação entre rigidez arterial e função renal depende das condições de diabetes e hipertensão é uma questão controversa. Objetivo Investigar a relação entre a rigidez arterial, por velocidade da onda de pulso carotídea-femoral (VOPcf), e a incidência de doença renal crônica (DRC) em indivíduos e verificar se essa associação está presente em indivíduos sem hipertensão e diabetes. Métodos Estudo longitudinal com 11.647 participantes do ELSA-Brasil acompanhados por quatro anos (2008/10-2012/14). A VOPcf basal foi agrupada por quartil, de acordo com pontos de corte específicos com relação a sexo. A presença de DRC foi verificada pela taxa de filtração glomerular (TFGe-CKD-EPI) < 60 ml/min/1,73 m2 e/ou relação albumina/creatinina ≥ 30 mg/g. Modelos de regressão logística foram executados para toda a coorte e uma subamostra livre de hipertensão e diabetes no início do estudo, após ajuste para idade, sexo, raça, escolaridade, tabagismo, relação colesterol/HDL, índice de massa corporal, diabetes, uso de anti-hipertensivos, pressão arterial sistólica, frequência cardíaca e doenças cardiovasculares. A significância estatística foi fixada em 5%. Resultados A chance de DRC foi de 42% (IC de 95%: 1,05;1,92) maior entre indivíduos no quartil superior da VOPcf. Entre os participantes normotensos e não diabéticos, os indivíduos do 2º, 3º e 4º quartis da VOPcf apresentaram maiores chances de desenvolver DRC, quando comparados aos do quartil inferior, sendo a magnitude dessa associação maior para aqueles do quartil superior (OR: 1,81 IC de 95%: 1,14;2,86). Conclusão A maior VOPcf aumentou as chances de DRC, e sugere que esse efeito é ainda maior em indivíduos sem diabetes e hipertensão.
Abstract Background Arterial stiffening can directly affect the kidneys, which are passively perfused by a high flow. However, whether the relation between arterial stiffness and renal function depends on diabetes and hypertension conditions, is a matter of debate. Objective To investigate the relationship between arterial stiffening by carotid-to-femoral pulse wave velocity (cfPWV) and chronic kidney disease (CKD) incidence in individuals and verify whether this association is present in individuals without hypertension and diabetes. Methods A longitudinal study of 11,647 participants of the ELSA-Brasil followed up for four years (2008/10-2012/14). Baseline cfPWV was grouped per quartile, according to sex-specific cut-offs. Presence of CKD was ascertained by glomerular filtration rate (eGFR-CKD-EPI) < 60 ml/min/1.73 m2 and/or albumin-to-creatinine ratio ≥ 30 mg/g. Logistic regression models were run for the whole cohort and a subsample free from hypertension and diabetes at baseline, after adjustment for age, sex, race, schooling, smoking, cholesterol/HDL ratio, body mass index, diabetes, use of antihypertensive, systolic blood pressure, heart rate, and cardiovascular disease. Statistical significance was set at 5%. Results The chance of CKD was 42% (CI 95%: 1.05;1.92) greater among individuals in the upper quartile of cfPWV. Among normotensive, non-diabetic participants, individuals in the 2nd, 3rd, and 4th quartiles of cfPWV presented greater chances of developing CKD, as compared to those in the lower quartile, and the magnitude of this association was the greatest for those in the upper quartile (OR: 1.81 CI 95%: 1.14;2.86). Conclusion Higher cfPWV increased the chances of CKD and suggests that this effect is even greater in individuals without diabetes and hypertension.
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Abstract Background Arterial stiffness and hypertension are strong predictors of cardiovascular disease and mortality. Angiotensin-converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB) are first-line antihypertensive agents in reducing blood pressure and arterial stiffness. Objective The objective of this study was to compare the effects of ACEI and ARB in reducing arterial stiffness and preventing target organ damage in patients with hypertension. Methods This observational study included 654 participants who attend routine consultations at an outpatient hypertension clinic in 2 university hospitals. Patients were interviewed, and they underwent central and peripheral blood pressure measurements. Doppler echocardiography, carotid ultrasound, biochemical tests, and anthropometric parameters were carried out. Shapiro-Wilk, chi-square, and Fisher's exact test were used. A significance level of 5% was adopted. Results A total of 659 participants were evaluated in the study (398 from the ARB group and 256 from the ACEI group). Age, body mass index (BMI), central and peripheral blood pressure measurements, pulse wave velocity (PWV), left ventricular mass index, and carotid intima-media thickness did not show differences between the groups (p > 0.05). After linear regression analysis, the ACEI group had lower values of total vascular resistance (TVR) (p = 0.003) and augmentation pressure (p = 0.008), when compared to the ARB group. Conclusion This study showed that the ACEI group had a greater reduction in augmentation pressure and PWV. There were no differences between the groups regarding the improvement of outcomes related to central arterial pressure, PWV, and cardiac and vascular target organ damage.
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Objectives: Micro and macrovasculopathy are common complications of undertreated or undiagnosed type 2 diabetes mellitus (T2DM) patients. One of the underlying factors of macrovasculopathy is arterial stiffness, which may lead to cardiovascular and cerebrovascular diseases. Understandably, diabetic micro and macrovasculopathy affect vital functions, which may affect the well-being of the individual. However, few studies have attempted to determine arterial stiffness, cardiac autonomic neuropathy (CAN) and lipid profile separately in South Asian population and examined its associations with T2DM. Moreover, there is a need to understand the mechanistic links among cardiovascular risk factors. This forms the basis of the present study. Materials and Methods: T2DM patients of 53–62 years and age- and gender-matched healthy control subjects were recruited in the cross-sectional and observational study (n = 30 each, eight women). Anthropometric measurements, physiological parameters such as resting heart rate, peripheral blood pressure (PBP), central blood pressure (CBP), augmentation index% (AIx%), brachial-ankle pulse wave velocity and lead II ECG for analysis of heart rate variability parameters were recorded after obtaining the consent of the study participants. The lipid profile and fasting blood glucose were also analysed. Results: Peripheral systolic blood pressure was significantly higher (P = 0.05) in T2DM patients. Dyslipidaemia was evident in T2DM patients. Atherogenic index of plasma (AIP) was also significantly higher in T2DM patients. Correlation analysis revealed a positive association between AIx% with PBP and CBP as well as between AIP index and central systolic blood pressure, serum triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and very low-density lipoprotein cholesterol (VLDL-C) levels. AIP index was found to be negatively associated with HF (nu). Serum TG, high-density lipoprotein cholesterol (HDL-C) levels and AIP index have emerged as significant independent predictors of T2DM vasculopathy by multiple regression analysis. Conclusion: In the present study, atherogenic dyslipidaemia was observed in T2DM patients in combination with increased serum levels of TG, VLDL-C and decreased serum levels of HDL-C. Moreover, AIP index, a predictor cardiovascular risk, was found to be significantly higher in T2DM patients. Dyslipidaemia was found to be associated with dysregulation of autonomic nervous system in those patients. A positive association between noninvasive, surrogate markers of arterial stiffness with PBP and CBP indicates that enhanced arterial stiffness may elevate systemic arterial pressure. Therefore, early screening of T2DM patients for the estimation of serum lipid profile, arterial stiffness and cardiac autonomic neuropathy may be performed to unravel diabetic vasculopathy.
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Background Few studies have investigated the association between air pollution and arterial stiffness in Chinese population, and the findings are inconsistent. The problem of multicollinearity exists when modeling multiple air pollutants simultaneously. Objective To investigate potential association between air quality index (AQI) and population brachial-ankle pulse wave velocity (baPWV) in Beijing. Methods This study retrieved medical examination data of 2971 participants from the Beijing Health Management Cohort, who were under 60 years old and not yet retired, from January 1, 2015 to December 31, 2019. The most recent medical examination data available were utilized for this analysis. AQI data from 35 air pollution monitoring sites in Beijing and meteorological data (including atmospheric pressure, air temperature, wind speed, and relative humidity) from 16 meteorological monitoring stations from January 1, 2014 to December 31, 2019 were collected. An average AQI exposure level for 365 d before the date of physical examination for each participant was computed using inverse distance weighting. Multiple linear regression analysis was employed to investigate the relationship between AQI and baPWV in Beijing, after adjusting for confounding variables including age, gender, body mass index, mean arterial pressure, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, fasting blood glucose, atmospheric pressure, temperature, wind speed, relative humidity, medication history of diabetes, medication history of hypertension, cardiovascular disease, education, smoking status, drinking status, and physical activity intensity. Subgroup analysis was performed by age, sex, presence of diabetes, and presence of hypertension. Results AQI demonstrated an overall decreasing trend during the study period and was lower in the northern regions and higher in the southern regions of Beijing. After adjusting the confounding variables, each 10 unit increase in AQI was associated with 6.18 (95%CI: 1.25, 11.10) cm·s−1 increase in baPWV in all participants, 8.05 (95%CI: 2.32, 13.79) cm·s−1 increase in the participants <50 years, 15.82 (95%CI: 8.33, 23.31) cm·s−1 increase in the female group, 10.10 (95%CI: 4.66, 15.55) cm·s−1 increase in the participants without diabetes, and 9.41 (95%CI: 4.21, 14.62) cm·s−1 increase in the participants without hypertension. However, there was no statistically significant association observed between AQI and baPWV in the age group ≥50 years, the male group, the diabetic group, and the hypertensive group (P>0.05). Conclusion An increase in long-term AQI levels is associated with an elevation in the degree of arterial stiffness. Individuals under 50 years old, females, without hypertension or diabetes are susceptible populations to arterial stiffness when being exposed to air pollution. Improving air quality may contribute to prevent arterial stiffness.
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Objective:To evaluate the value of shear wave elastography (SWE) in skin assessment of Systemic sclerosis (SSc).Methods:A total of 58 SSc patients admitted to Peking University Third Hospital from May 2021 to October 2022 and 41 healthy volunteers were included in the study. Skin shear wave elastography (SWE) was performed at 17 sites defined in modified Rodnan skin score (mRSS) measurement, and shear wave velocity values were recorded to evaluate skin hardness. SPSS 22.0 software was used to analyze the skin hardness of SSc patients and healthy controls, and the correlation between skin hardness of SSc patients and clinical data was analyzed. A logistic regression model was constructed to evaluate the diagnostic efficacy of skin hardness at different sites of SSc patients, and to further select the most practical measurement site.Results:The SWE value of SSc patients was significantly higher than that of healthy control group ( P<0.05). There was a positive correlation between SWE and mRSS in the measurement of bilateral fingers, bilateral dorsal hands, bilateral forearms, fore-chest, abdomen, bilateral thighs, and bilateral dorsal feet. Skin stiffness measured by SWE was significantly correlated with SSc disease activity score (EScSG-DAI), ( r=0.71, P<0.001), disease injury score (SCTC-DI), (P=0.55, P=0.005) and functional score (HAQ-DI), ( r=0.46, P=0.003). Reducing the number of measurement sites to 12 (bilateral fingers, bilateral hands, bilateral forearms, bilateral upper arms, forehead, fore-chest, bilateral dorsum of feet) performs as well as all 17 measurement sites simultaneously in assessing disease activity. Conclusion:SWE is a good evaluation tool to reflect the skin lesions of SSc, which is of great value for the diagnosis and evaluation of the disease. We can further standardize the measurement sites and select the most appropriate evaluation strategy, so as to achieve better clinical application.
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Objective:To study the value of sound touch elastography (STE) linear combined with ultrasound score (US) in the diagnosis of chronic hepatitis B (CHB) liver fibrosis, and to investigate whether their combination can improve the diagnostic efficiency of subdividing the degree of CHB liver fibrosis. Furthermore, a comparison with STE linear combined with the serological model was performed to seek the optimal linear combination model.Methods:A total of 313 subjects were enrolled from September 2018 to December 2021 in Shenzhen Third People′s Hospital Affiliated to Guangdong Medical University, including 259 patients with CHB who had completed liver biopsy and 54 healthy volunteers. CHB patients were divided into liver fibrosis group (F1-F4 group) according to METAVIR classification standard, and healthy volunteers were used as the control group. All subjects underwent liver ultrasound examination, STE and blood biochemical indexes of liver function. The US was performed according to the liver ultrasound examination, and the liver stiffness measurement (LSM) was measured by STE, aspartate aminotransferase and platelet ratio index (APRI) was calculated by blood biochemical index. Fisher discriminant analysis was used to establish the linear combination (LC) diagnostic marker of US and LSM, and the linear combination (LC2) diagnostic marker of LSM and APRI, successively. Spearman rank correlation coefficient was used to analyze the correlations between US, LSM, APRI, LC2, LC and pathological results. The ROC curves of US, LSM, APRI, LC2 and LC for diagnosing CHB liver fibrosis were plotted, and the diagnostic efficiency of above diagnostic markers was evaluated according to the accuracy, sensitivity, specificity and area under the ROC curve (AUC).Results:The formula for the linear combination of US and LSM was LC=0.986 0×US+ 0.166 7×LSM, and LC was highly positively correlated with pathological findings ( rs=0.851, P<0.001), higher than US, LSM, LC2 and APRI ( rs=0.825, 0.775, 0.802, 0.586, all P<0.001). LC showed the best diagnostic efficiency. The AUCs for diagnosing ≥F1, ≥F2, ≥F3 liver fibrosis and =F4 cirrhosis were 0.945, 0.911, 0.954, 0.955, respectively, which superior to the AUCs of US (0.913, 0.879, 0.934 and 0.916, respectively), the AUCs of LSM (0.860, 0.871, 0.934 and 0.952, respectively) and the AUCs of LC2(0.899, 0.883, 0.941, 0.946, respectively). Compared with US, the AUC of LC diagnosis of ≥F1, ≥F2, ≥F3 liver fibrosis and =F4 cirrhosis increased by 3.2%, 3.2%, 2.0% and 3.9%, respectively, with all significant differences ( P<0.05). Compared with LSM, the AUC of LC increased by 8.5%, 4.0%, 2.0% and 0.3%, respectively, with significant difference ( P<0.05) except for stage =F4 cirrhosis.Compared with LC2, the AUC of LC increased by 4.6%, 2.8%, 1.3% and 0.9%, respectively, and there were significant differences in the diagnosis of ≥F1 and ≥F2 liver fibrosis ( P<0.05). Moreover, the overall efficiency of LC2 was not significantly improved than LSM, the difference was not significant ( P>0.05). Conclusions:US, LSM, LC2 and LC can be used to diagnose the degree of CHB liver fibrosis, but LC is better than US or LSM and LC2 alone, especially in the subdivision of mild liver fibrosis, which is a promising new diagnostic marker to subdivide the degree of CHB liver fibrosis.
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Objective:To explore the level of arterial stiffness and its influencing factors in prediabetic population.Methods:From June 2021 to June 2022, 207 prediabetes patients were prospectively and randomly recruited from the physical examination center and outpatient clinic of Tangdu Hospital of Air Force Military Medical University to be the prediabetic group and 130 healthy volunteers at the same time with the same gender and age as the healthy controls. The carotid-femoral pulse wave velocity (PWV), brachial-radial PWV, and femoral-ankle PWV were measured by an automatic ultrasonic arterial stiffness measurement technology. The common carotid artery wall intima-media thickness (IMT) and left heart function were routinely evaluated. A questionnaire was designed to investigate the subjects′ smoking, drinking, diet, staying up late, exercise and other living habits. Comparison between groups and multivariate linear regression analysis were used to analyze the relevant data.Results:The carotid-femoral PWV and common carotid artery wall IMT in prediabetic group were significantly higher than those in healthy controls [(7.10±2.00)m/s vs (6.26±1.14)m/s, (0.57±0.11)mm vs (0.51±0.08)mm; both P<0.001], but there were no significant differences in the brachial-radial PWV and femoral-ankle PWV between the two groups (both P>0.05). Multivariate linear regression analysis showed that prediabetes was an independent influencing factor in carotid-femoral PWV after adjusting for confounding factors ( P<0.001), in addition, age ( P<0.001), diastolic blood pressure ( P<0.001), staying up late ( P=0.011) and low density lipoprotein cholesterol ( P=0.022) were also the independent influencing factors of carotid-femoral PWV. Conclusions:Compared with healthy people, the stiffness of aorta is significantly increased in prediabetic people, but there is no significant change in the stiffness of peripheral arteries. Prediabetes, age, diastolic blood pressure, staying up late and low density lipoprotein cholesterol are independent influencing factors of carotid-femoral PWV.
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Objective:To measure liver and spleen stiffness in patients with BCR-ABL-negative myeloproliferative neoplasms and analyze their clinical significance.Methods:Fifteen healthy volunteers and 27 patients with BCR-ABL-negative myeloproliferative neoplasms underwent liver and spleen thickness measurements using FibroScan 502 Touch medical device between June 2018 and June 2020 in Hebei Petro China Central Hospital and they were included in this study. Liver and spleen stiffness was correlated with clinical laboraty indicators.Results:Liver stiffness, spleen stiffness, and the difference between spleen stiffness and liver stiffness in patients with BCR-ABL-negative myeloproliferative neoplasms were significantly greater than those in healthy controls [(6.34 ± 2.22) kPa vs. (5.07 ± 1.27) kPa; (26.00 ± 10.66) kPa vs. (13.61 ± 5.64) kPa; (19.65 ± 10.37) kPa vs. (8.54 ± 5.33) kPa, t = -2.01, -4.30, -4.06, all P < 0.05]. Platelet count was negatively correlated with liver and spleen stiffness ( r = -0.39, -0.42). White blood cell count was negatively correlated with the difference between spleen stiffness and liver stiffness ( r = -0.40, P < 0.05). The uric acid level was negatively correlated with liver stiffness ( r = -0.54, P < 0.05), but it was positively correlated with spleen thickness ( r = 0.41, P < 0.05). The percentage of B lymphocytes among lymphocytes was negatively correlated with spleen stiffness and the difference between spleen stiffness and liver stiffness ( r= -0.56, -0.56, both P < 0.05). The percentage of diseased megakaryocytes was positively correlated with spleen stiffness ( r = 0.40, P < 0.05). The percentage of sideroblasts was negatively correlated with liver stiffness ( r = -0.44, P < 0.05). Conclusion:Spleen stiffness and liver stiffness are closely related to clinical indicators in patients with BCR-ABL-negative myeloproliferative neoplasms, including white blood cell count, platelet count, uric acid level, percentage of B lymphocytes, diseased megakaryocytes and sideroblasts. Dynamic monitoring of liver and spleen stiffnesses or in combination with bone marrow examination in future can help evaluate the condition of patients with BCR-ABL-negative myeloproliferative neoplasms.
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ObjectiveTo analyze the characteristics of plantar pressure of diabetic patients during gait cycle, and to design a offloading insole with variable stiffness. MethodsThe plantar pressure experiment was carried out and a database including 157 subjects was established. The differences of plantar pressure distribution were analyzed among diabetic patients with and without peripheral neuropathy, and healthy people. The insole pressure area was divided, and porous units were filled in different insole areas according to the pressure gradient. The fed-calf-insole finite element model of diabetic patients was constructed. The simulation analysis of different insole schemes was carried out under the conditions of push-off, footheel-strike and dynamic neutrality posture, and to explore the most reasonable insole stiffness design. ResultsCompared with the healthy group, the percentage of peak pressure and high pressure in the left and right heel areas of diabetic neuropathy patients showed a decreasing trend, in which the left peak pressure was significantly reduced by 11% (P = 0.026) and the percentage of high pressure was significantly reduced by 9.8% (P = 0.02). When the porous elements of 2.5 MPa and 1.9 MPa were used in the high pressure area of the insole metatarsal and high pressure area of the heel, the peak plantar pressure of footheel-strike, dynamic neutral and push-off was reduced by 42.4%, 27.4% and 26.4%, and the peak stress of the soft tissue was reduced by 49.8%, 43.6% and 25.1%, respectively. ConclusionThere is a higher risk of ulcer in the metatarsal region than in the heel region for diabetic patients. The variable stiffness insoles based on the optimization of plantar pressure and internal stress under multi-posture can effectively reduce the peak pressure of plantar and peak stress of soft tissue during walking, which provides a reference for the design of variable stiffness insoles.
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Liver stiffness measurement (LSM) has been widely used in predicting portal hypertension in clinical practice, and in recent years, spleen stiffness measurement (SSM) has also become a diagnostic tool. Studies have shown that SSM can predict portal hypertension and its complications such as esophagogastric variceal bleeding in patients with chronic liver diseases and assist in the risk stratification management of portal hypertension and esophagogastric variceal bleeding. It can accurately predict clinically significant portal hypertension, high-risk esophageal and gastric varices, decompensation rate, and mortality rate in patients with chronic liver diseases. At present, SSM data in most studies are obtained by detection using the liver equipment FibroScan Ⓡ (SSM@50 Hz). FibroScan Ⓡ 630 is a new scanner dedicated for SSM with a special mode for SSM (SSM@100 Hz). This article elaborates on the significance of SSM in predicting portal hypertension and briefly introduces the advantages and disadvantages of the new equipment for SSM.
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Elbow arthrolysis is the most commonly used treatment for elbow stiffness. Ulnar nerve complications are one of the most important evaluation indicators of postoperative health status. However, there is no consensus on the management of ulnar nerve and the control of surgical indications. Combining relevant literature and clinical experience, this review discussed the necessity of ulnar nerve release and the choice of ulnar nerve operations during elbow arthrolysis with or without preoperative ulnar nerve symptoms. It is considered that more attention should be paid to the management of ulnar nerve complications and further research should be performed.
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Objective:To study the clinical efficacy of modified open elbow arthrolysis in the treatment of traumatic elbow stiffness.Methods:A retrospective analysis was performed on 120 patients who underwent modified open elbow arthrolysis in Beijing Jishuitan Hospital from January 2018 to December 2020. The age of the included patients was (37.7±12.4) years (ranged 18-64 years), including 54 males and 66 females. The medical records were reviewed, the range of motion (ROM) and functional status of the patients before operation and at the last follow-up were compared including visual analogue scale (VAS), Mayo elbow performance score (MEPS), Disabilities of the arm, shoulder and hand (DASH) score. Complications and secondary operations were also recorded. Measurement data with normal distribution were presented as mean ± standard deviation( ± s) and comparison between groups was conducted using the t-test; Measurement data of skewed distribution were expressed as M ( Q1, Q3), and Rank-sum test was used for inter-group comparison. Results:The preoperative extension of 120 patients was 43.6° (33.8°, 60.1°), the flexion was 78.7° (59.8°, 98.1°), and the flexion-extension ROM was 25.6° (0.0°, 54.5°); the preoperative pronation was 51.8° (33.0°, 67.0°), the supination was 85.1° (65.7°, 90.0°), and the rotation ROM was 136.9° (99.1°, 157.5°). Postoperative extension was 14.2° (7.0°, 24.8°), flexion was 129.5° (120.0°, 138.1°), flexion-extension ROM was 115.5° (94.4°, 127.3°); postoperative pronation was 65.0° (47.1°, 75.0°), the supination was 88.3° (78.6°, 90.0°), and the rotation ROM was 151.9° (131.7°, 163.4°). Postoperative extension, flexion, flexion-extension ROM, pronation, supination, and rotation ROM were all higher than those before operation, and the differences were statistically significant ( P<0.001). The VAS of 120 patients was 1.0 (0.0, 3.0) scores before operation and 0.0 (0.0, 1.0) scores after operation. The MEPS was 60.0 (50.0, 75.0) scores before operation and 100.0 (85.0, 100.0) scores after operation. The preoperative DASH was 37.5 (20.1, 51.3) scores, and the postoperative DASH was 7.9 (3.3, 13.3) scores. The postoperative VAS, MEPS, and DASH were significantly improved compared with those before operation, and the differences were statistically significant ( P<0.001). Residual ulnar nerve symptoms occurred in 18 cases, recurrence of heterotopic ossification in 42 cases, and hematoma in 3 cases. Conclusions:Modified open elbow arthrolysis is a safe and effective surgical method for the treatment of traumatic elbow stiffness. It can significantly improve the function of the patient, reduce the occurrence of elbow instability, avoid the use of external fixators, and reduce the cost of the patient.
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Objective An X-shaped cushioning insole with variable stiffness was designed to explore its effects on plantar pressure and internal stress of diabetic patients with toe amputation. Methods Based on CT images, the feet-calf finite element model of diabetic patients with toe amputation was established, and the insole was divided into different areas according to distribution characteristics of the planter pressure. The three-dimensional (3D) printed cushioning insole with an X-shaped sandwich structure was designed. The modulus of the sandwichstructure was changed by changing thickness of the sandwich structure panel. For simulation analysis, the divided area was filled with the X-shaped sandwich structure with different modulus. Results The peak plantar pressure of diabetic patients with toe amputation was in calcaneal region, and the combined insoles with 1. 2 mpanel thickness in toe area, 1. 4 mm panel thickness in metatarsal area, 2. 0 mm panel thickness in middle area and 1. 6 mm panel thickness in heel area had the best decompression effect. Compared with bare feet, the peak pressure in heel area of the insole, the peak pressure in phalangeal head area and the stress in plantar softissues were reduced by 40. 18% , 31. 7% , and 50. 44% , respectively. Conclusions The 3D printed insoles with variable stiffness can effectively reduce surface pressure and internal stress of the sole and reduce probability of the 2nd toe amputation
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Objective To investigate the difference of matrix stiffness in different regions of tibial plateau in osteoarthritis (OA) and its effects on morphology of the cartilage and mitochondria. Methods The tibial plateau cartilage specimens of OA were obtained for nanoindentation test, transmission electron microscopy and histological analysis. The stiffness of cartilage matrix in different regions of OA tibial plateau was detected by nano-indentation. The morphology of cartilage mitochondria in different regions was observed by transmission electron microscopy, and the changes of mitochondrial plane area, shape and ridge volume density were quantitatively analyzed. Cartilage injury in different regions of OA tibial plateau was observed by histological staining. Results The cartilage of OA tibial plateau showed regional heterogeneity, and the cartilage and mitochondria on medial side of varus knee OA were more severe, and the matrix stiffness was higher. The OA scores were positively correlated with matrix stiffness. There was also a significant correlation between OA scores and mitochondrial morphology: the higher OA scores, the larger and rounder mitochondrial plane area, and the lower cristae volume density. Conclusions The differences of tibial plateau revealed the correlation between cartilage matrix stiffness, OA scores and mitochondrial morphological parameters. The increased cartilage matrix stiffness may be the main cause of chondrocyte mitochondrial injury, and further aggravate the progression of OA.
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Objective To explore the effects from the synergy of substrate stiffness and hypoxia on epithelial mesenchymal transition (EMT) of colon cancer cells SW480 by simulating the microenvironment of human colon cancer tissues. Methods Polyvinyl alcohol gels with different stiffness ( 4. 5, 20, 40 kPa) were prepared to simulate the stiffness of each part of colon cancer tissues. The morphological change of cells on substrate with different stiffness was detected under simulated hypoxia ( CoCl2 ) environment. The expression of hypoxia inducible factor (HIF-1α), and EMT markers E-cadherin, Vimentin, Snail 1 were detected by Western blot. The mRNA expression of E-cadherin, Vimentin, Snail 1, matrix metalloproteinase-2 ( MMP-2), and MMP-9 was detected by quantitative real-time PCR ( qRT-PCR). Results Under simulated hypoxia environment, with the increase of substrate stiffness, the SW480 cells spreading area increased, and transformed from round shape into irregular polygon. The EMT of SW480 could be enhanced through up-regulating expression of Vimentin, Snail 1, MMP-2, MMP-9, and down-regulating expression of E-cadherin. Conclusions This study is important for exploring the synergistic effect of substrate stiffness and hypoxia on the EMT of colon cancer cells as well as the molecular mechanism.
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The mechanical microenvironment of cells plays a critical role in regulating the physiological function of cells. Cells in vivo are often subjected to a variety of mechanical forces from their mechanical micro-environment, such as shear, tension, and compression. At the same time, cells can adhere to the extracellular matrix (ECM) through adhesion molecules (such as integrin-ligand binding), and further sense the stiffness of the ECM. Cell mechanics mainly studies the properties and behavior of living cells under mechanical forces, and how they relate to cell functions. This review summarized the advances in cell mechanics in 2022, focusing on integrin-ligand interactions and the effects of matrix stiffness and mechanical forces on cell physiological behavior and morphogenesis.
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Idiopathic pulmonary fibrosis (IPF) is a common chronic interstitial fibrotic disease. During the fibrosis process, myofibroblasts are abnormally activated, collagen is deposited in large quantities and the biomechanical characteristics of lung tissue are significantly altered. In this paper, a systematic review about the changes in lung tissues, cellular biomechanical properties and biomechanical signals during the process of IPF was presented, and the in vitro reproduction of biomechanical features and therapeutic strategies for targeting biomechanics wassummarized, so as to provide references for clinical prevention and treatment of IPF.
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Objective After hydrogen bonding between collagen ( COL) and silk fibroin ( SF ) at different concentrations, a composite scaffold with adjustable stiffness was prepared by combining with gel system, and its physical and chemical properties were characterized. Methods SF with different qualities was dissolved in sodium alginate (SA) solution, then COL solution at different concentration and calcium carbonate ( CaCO3 ) powder were added. The hydrogels of SC1, SC2, and SC3 groups were obtained by taking out the mixed solution and adding some gluconic acid lactone ( GDL) powder, and different SF scaffolds were obtained after freeze drying. Results The SF scaffolds with adjustable stiffness were successfully prepared. The compression moduli of SC1, SC2, and SC3 groups were (17. 31±2. 73), (24. 12±1. 81), (32. 54±1. 81) kPa, respectively. The innerstructure of the scaffolds was observed. From SC1 group to SC3 group, pores of the scaffolds were smaller and fewer, and hydrophilicity of the materials become better and better. Conclusions Three-dimensional ( 3D) porous scaffolds with different matrix stiffness can be prepared by changing the concentration of SF and COL solution. The concentration of SF and COL is proportional to the compression modulus, water absorption, water retention and swelling rate of SF scaffolds, while inversely proportional to porosity. The findings of this study are expected to provide theoretical guidance for construction of scaffolds with appropriate matrix stiffness for inducing osteogenic differentiation of mesenchymal stem cells
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OBJECTIVE@#To utilized the baseline data of the Beijing Fangshan Family Cohort Study, and to estimate whether the association between a healthy lifestyle and arterial stiffness might be modified by genetic effects.@*METHODS@#Probands and their relatives from 9 rural areas in Fangshan district, Beijing were included in this study. We developed a healthy lifestyle score based on five lifestyle behaviors: smoking, alcohol consumption, body mass index (BMI), dietary pattern, and physical activity. The measurements of arterial stiffness were brachial-ankle pulse wave velocity (baPWV) and ankle-brachial index (ABI). A variance component model was used to determine the heritability of arterial stiffness. Genotype-environment interaction effects were performed by the maximum likelihood methods. Subsequently, 45 candidate single nucleotide polymorphisms (SNPs) located in the glycolipid metabolism pathway were selected, and generalized estimated equations were used to assess the gene-environment interaction effects between particular genetic loci and healthy lifestyles.@*RESULTS@#A total of 6 302 study subjects across 3 225 pedigrees were enrolled in this study, with a mean age of 56.9 years and 45.1% male. Heritability of baPWV and ABI was 0.360 (95%CI: 0.302-0.418) and 0.243 (95%CI: 0.175-0.311), respectively. Significant genotype-healthy diet interaction on baPWV and genotype-BMI interaction on ABI were observed. Following the findings of genotype-environment interaction analysis, we further identified two SNPs located in ADAMTS9-AS2 and CDH13 might modify the association between healthy dietary pattern and arterial stiffness, indicating that adherence to a healthy dietary pattern might attenuate the genetic risk on arterial stiffness. Three SNPs in CDKAL1, ATP8B2 and SLC30A8 were shown to interact with BMI, implying that maintaining BMI within a healthy range might decrease the genetic risk of arterial stiffness.@*CONCLUSION@#The current study discovered that genotype-healthy dietary pattern and genotype-BMI interactions might affect the risk of arterial stiffness. Furthermore, we identified five genetic loci that might modify the relationship between healthy dietary pattern and BMI with arterial stiffness. Our findings suggested that a healthy lifestyle may reduce the genetic risk of arterial stiffness. This study has laid the groundwork for future research exploring mechanisms of arterial stiffness.