Tissue Hardness Research Articles

Comparison of the effects of different foam rolling durations on knee extensors function.

Foam rolling (FR) intervention has recently attracted attention in sports and rehabilitation settings. However, the effects of FR using different rolling durations have not been fully clarified. Thus, this study focused on FR durations and examined the acute and prolonged (i.e., 20-min; 40-min, 60-min) effects of different FR intervention durations on maximal voluntary concentric contractions (MVC-CON), knee flexion range of motion (ROM), pain pressure threshold (PPT), and tissue hardness. The participants were 10 male university students (22.5 ± 1.0 years), and the target muscles were the dominant leg knee extensors. Three sets of 60-seconds FR interventions were performed in the randomized crossover trials in each condition. The three intervention conditions were fast (1 rolling/2 s, 30-repetition × 3 sets, 90 repetitions), medium (1 rolling/6 s, 10-repetition × 3 sets, 30 repetitions), and slow speed (1 rolling/12 s, 5-repetition × 3 sets, 15 repetitions). Before as well as immediately, 20-min, 40-min, and 60-min after the interventions, MVC-CON, ROM PPT, and tissue hardness were measured. The results showed no interaction effect in the acute effect but a main effect of time for all variables (p < 0.05). Also, no interaction was observed in prolonged effect, but main effects of time were observed in knee flexion ROM, PPT, and tissue hardness (p < 0.01) but not for MVC-CON. Post-hoc tests showed significant PPT (p < 0.05) and knee flexion ROM (p < 0.01) increases up to 20- and 60-minutes respectively after all interventions. Tissue hardness was significantly (p < 0.01) decreased up to 60-minutes after all interventions. This study showed that the FR intervention changed ROM, PPT, tissue hardness, and MVC-CON regardless of rolling duration and that the effects persisted up to 20-60 minutes.

Comparison of acute and prolonged effects of short-term foam rolling and vibration foam rolling on the properties of knee extensors.

Recently, Foam Rolling (FR) and Vibration Foam Rolling (VFR) have attracted attention in sports and rehabilitation fields. Previous studies have shown that FR and VFR acute interventions effectively increase the range of movement (ROM) and decrease tissue hardness. For application to sports and rehabilitation, it is necessary to compare the acute and prolonged effects of short duration FR and VFR. Therefore, this study aimed to compare and investigate the acute and prolonged (15 minutes) effects of short duration (30-s) FR and VFR interventions on knee extensors. The subjects were 14 male university students (22.4 ± 1.0 years old), in which the knee extensors of the dominant leg were tested. In a cross-over trial, 30-s of FR or VFR were performed with 2-s rolling of the anterior thigh (15 rolls). The frequency of VFR was 35 Hz. Measurements included knee flexion ROM, pain pressure threshold (PPT), tissue hardness, and countermovement jump height. The results of this study showed no interaction effects for all variables, but main time effects were observed for knee flexion ROM, PPT, and tissue hardness. Post-hoc tests showed that knee flexion ROM increased up to 10 minutes after the intervention. PPT significantly increased, and tissue hardness significantly decreased up to 15 minutes after intervention. This study showed that 30-s FR and VFR interventions effectively increased ROM, PPT, and decreased tissue hardness. The effects were prolonged up to 10-15 minutes after the intervention. The results of this study show no advantage of VFR over FR with acute short-term interventions.

Application of Acoustic Radiation Force Pulse Imaging Technology in the Evaluation of the Efficacy of Calf Intermuscular Vein Thrombosis.

The continuous advancement in ultrasound technology has given rise to Acoustic Radiation Force Impulse (ARFI) elastography, which boasts non-invasiveness, ease of operation, rapid inspection, and high accuracy. It has been successfully employed in detecting tissue hardness across various diseases. This study aims to investigate the application of acoustic radiation force pulse imaging technology in evaluating the efficacy of calf intermuscular vein thrombosis. This study is retrospective in nature, involving a total of 120 patients diagnosed with calf intermuscular venous thrombosis (MCVT) who were admitted to our hospital. These patients were selected retrospectively as the subjects for our research. They were subsequently divided into two groups: the control group and the observation group. The control group received standard nursing care and simple pressure therapy, while the observation group underwent anticoagulant drug treatment. The shear wave elastic hardness of both groups was measured, with the recording of ultrasonic elasticity scores and the average elastic modulus value (E-mean, in kPa). Furthermore, a comparison was made between the two groups regarding thrombus disappearance time, blood flow patency, and the clinical treatment effect. At the 1, 3, and 6-month marks of the treatment period, the ultrasonic elasticity scores in the observation group were consistently higher compared to those in the control group. Additionally, the shear wave elastic hardness in the observation group was consistently lower than that in the control group, and these differences were found to be statistically significant (p < 0.05). The total effective rates for the control and observation groups were 83.33% and 95.00%, respectively. Notably, the clinical total effective rate in the observation group was significantly higher than that in the control group, and this difference was statistically significant (p < 0.05). The thrombus disappearance time in the observation group was significantly shorter than that in the control group, and the blood flow rate was significantly higher than in the control group, with both differences being statistically significant (p < 0.05). ARFI plays a crucial role in assessing the efficacy of MCVT by effectively revealing the hardness and location of the patient's thrombus tissue. This technology aids doctors in gaining a more precise understanding of the deep vein thrombosis condition. Notably, ARFI is characterized by high safety levels and exhibits positive effects due to its painless and non-invasive nature.

Analysis of bone metabolic alterations linked with osteoporosis progression in type 2 diabetic db/db mice

Type 2 diabetes (T2D) is a common chronic disease, characterized by persistent hyperglycemia and insulin resistance. This disorder is associated with decreased bone quality and an elevated risk of bone fractures. However, evidence on the relationship between systemic metabolic change and the development of type 2 diabetic osteoporosis (T2DOP) remains elusive. Herein, we investigate the changes of bone metabolites with bone loss in db/db mice (an animal model of T2DOP exhibited bone loss with age progression), and explore the potential metabolic mechanism underlying type 2 diabetes and osteoporosis. C57BKS male mice were distributed in four groups, consisting six mice in each group: 8w m/m, 24w m/m, 8w db/db and 24w db/db. Bone morphometric and biomechanical parameters of db/db mice were analyzed by micro-CT and materials tester, it was found that 24w db/db mice showed severe bone loss and decreased bone tissue hardness compared with misty/misty littermates. The tibia of misty/misty mice (8 weeks, 24 weeks) and db/db mice (8 weeks, 24 weeks) were screened for differential metabolites by UPLC-Orbitrap MS. Ninety-eight metabolites were identified (35 and 63 metabolites are associated with early staged and late staged, respectively), consisting of amino acids, fatty acyls, and nucleotides. Notably, fatty acyls (such as 18-HEPE, 16(17)-EpDPE, arachidonic acid) and glycerophospholipids (such as phosphocholines (PC) (O-10:1(9E)/0:0), PC (O-16:1(9E)/0:0) [U] and phosphatidylethanolamines (PE) (P-16:0/0:0)) were significantly increased, and metabolites of amino acid pathway (such as l-glutamine, proline, phenylalanine) showed a downregulation trend. Dysregulation of lipid and glutathione pathways is the major contributor to progression of T2DOP in C57BKS mice.

Effect of extracorporeal shock wave combined with Kinesio taping on upper limb function during individuals with biceps brachii tendinopathy：protocol for a double-blind, randomised controlled trial

IntroductionLong head of biceps brachii tendinopathy (LHBT) is characterised by persistent pain and disability of shoulder joint, impairing patients’ quality of life. Extracorporeal shock wave therapy (ESWT) is a non-invasive...

Comparison and development of scanning electron microscope techniques for delicate plant tissues

Cell deformation often occurs during sample preparation and imaging with scanning electron microscope (SEM), especially with delicate samples, which influences the accuracy of the results. Here we investigate the influence of several preparation methods on cell deformation, using water content and tissue hardness as indicators to classify “delicate” samples of plant species. The degree of deformation in samples resulting from five preparation methods was measured at the tissue and single-cell levels, revealing that a cryo- and methanol-fixation produced lower degrees of tissue dimension deformation and better preservation of cell shape for delicate samples, while for harder tissues, other preparation methods for a dehydrated specimen are also suitable. Stability and image quality of delicate samples could be improved with the application of a cryo-protectant combined with a lower cryo-stage temperature, e.g. − 30 °C. We show that the sample stability under the beam was improved by combining larger sample size and cryo-stage application. Furthermore, the influence of adaxial and abaxial tissue surfaces, the accelerating voltage, and sputter coating time on sample stability and image quality was evaluated. Our study is valuable for artifact reduction and easy application of SEM.

Acute Effects of Different Foam Roller Intervention Techniques on Knee Extensors.

The usefulness of Foam Roller (FR) even without a rolling stimulus (e.g., static compression with or without dynamic joint movements) has been recently demonstrated; however, the different effects of these methods remain unclear. Thus, this study aimed to compare and investigate the effects of such FR intervention methods on knee extensors. The dominant knee extensors of 20 male university students were investigated using the following four conditions: control (CON), FR with rolling (FR_rolling), FR with static compression (FR_SC), and FR with static compression + dynamic movement of the knee joint (FR_DM). FR_SC was intervened to compress the muscle belly of the knee extensors. FR_DM involved knee flexion and extension while maintaining the FR_SC condition. Knee flexion ROM, pain pressure threshold (PPT), tissue hardness, and countermovement jump (CMJ) height were outcome variables; they were compared before and immediately after the intervention. The results of this study showed that knee flexion ROM was significantly (p < 0.01) increased in FR_rolling (d = 0.38), FR_SC (d = 0.28), and FR_DM (d = 0.64). Tissue hardness was significantly (p < 0.01) decreased in FR_rolling (d = -0.55), FR_SC (d = -0.28), and FR_DM (d = -0.42). A main effect of time (p < 0.01) was observed in knee flexion ROM, PPT, and tissue hardness, but no change in CMJ was observed. The results of this study suggested that clinicians and athletes could choose any method they like as a warm-up routine.

Effect of the Pulsed Electric Field Treatment on Physical, Chemical and Structural Changes of Vacuum Impregnated Apple Tissue in Aloe Vera Juices

Vacuum impregnation (VI) stands as a diffusion-driven food processing method that has found recent application within the food industry, particularly for the cold formulation of fortified food products. Pulsed electric field (PEF) treatment can affect the food structure, influencing therefore the mass transfer phenomena during the further processing. Thus, the study aimed at investigating the effect of PEF treatment on selected physicochemical properties of vacuum-impregnated apples. Apple slices were vacuum impregnated with aloe vera juice solution with or PEF treatment at different intensities (125, 212.5 or 300 V/cm). The PEF was applied as a pretreatment—applied before the VI process as well as posttreatment—applied after the VI process. The VI process with aloe vera juice resulted in a sample weight increase of over 24% as well as structural changes, partial cell viability loss and color alteration. In addition, the decrease of bioactive compounds was observed, while antioxidant activity remained at a similar level as in raw material. PEF treatment adversely affected vacuum impregnation efficiency, causing microstructural changes and cell viability loss. Additionally, chemical composition modifications were evident through thermogravimetric analysis (TGA) and Fourier Infrared Spectroscopy (FTIR) analyses. Tissue hardness decreased significantly due to structural damage and caused high leakage from plant tissue, which resulted in hindering saturation with aloe vera juice during the VI process. Additionally, reduced bioactive substance content after PEF treatment was observed and the VI process did not restore apple samples of the bioactive compounds from aloe vera juice.

Antixenosis in Constitutive Resistance in Maize Genotypes to the Stink Bug Diceraeus melacanthus

Corn is one of the most important agricultural crops in the world, however, it can be affected by numerous phytophagous insects that causing economic losses in production. Diceraeus melacanthus belongs to the complex of pests that attack maize. The objective of this work was to evaluate 17 maize genotypes regarding the effects of antixenosis resistance to the stink bug D. melacanthus. The experiments were carried out in a greenhouse with maize plants in stage V2 and adult stink bugs. Bioassays of attractiveness and food preference were carried out, in addition to evaluating physical and morphological factors of the plants, such as tissue hardness, number of punctures and colorimetric factors. Genotypes 30A37, IAC 8390, Defender, NS 77 and Supremo Tg were the ones that expressed the greatest antixenotic effects in tests free choice and no-choice, among these Defender and Supremo Tg due to possible morphological causes such as plant tissue hardness. Although the IAC 8390 genotype also presents great potential for resistance, it was not possible to attribute its causes, so more studies should be conducted to evaluate the possible chemical constituents that give them this characteristic.

Effect of CO2 and H2 gas mixture in cold water immersion on recovery after eccentric loading

BackgroundThe findings of previous studies support the efficacy of cold water immersion (CWI) with carbon dioxide (CO2) in enhancing muscle blood flow and maintaining aerobic performance efficiency. We hypothesize that the addition of hydrogen gas (H2), known for its antioxidant properties and role in inflammation regulation, to C-CWI can enhance recovery after eccentric exercise. Subjectsand Methods: Thirty-four healthy subjects performed a knee-extensor eccentric exercise. They were randomly allocated into four groups: control, CWI, CO2-rich CWI (C-CWI), and CO2 + H2 gas mixture CWI (CH-CWI). In the three CWI groups, all subjects were immersed in the appropriate bath at 20 °C for 20 min immediately after 60 repetitions of eccentric exercise. Before exercise and after 48 h of recovery, the subjects' maximal voluntary isometric contraction torque (MVC-ISO), maximal voluntary concentric (MVC-CON) contraction torque, countermovement jump (CMJ) height, knee flexion range of motion (ROM), muscle soreness, and muscle thickness were measured. ResultsIn the CH-CWI group only, the MVC-ISO, CMJ height, and ROM did not decrease significantly post-exercise, whereas all of these decreased in the other three groups. Muscle soreness at palpation, contraction, and stretching significantly increased post-exercise in all groups. Echo intensity and tissue hardness did not increase significantly in the CH-CWI group. ConclusionsCH-CWI stimulated recovery from impairments in MVC-ISO torque, CMJ height, knee-flexion ROM, tissue hardness, and echo intensity. These findings indicate that CH-CWI can promote recovery after eccentric exercise.

Clinical Application of Ultrasound Elastic Imaging in Assessing Poststroke Complex Regional Pain Syndrome (CRPS).

This study aimed to explore the characteristics and clinical application of ultrasonic elastography in peripheral soft tissue in patients with poststroke complex regional pain syndrome (CRPS). Complex regional pain syndrome (CRPS) type I is also known as shoulder hand syndrome (SHS). Its main symptoms include shoulder pain, limited activity, upper arm, wrist, and knuckle joint pain. Ultrasonic elastic imaging technology is gradually being applied to musculoskeletal system evaluation, primarily for the elastic examination of superficial tissue, as a result of the continual advancements in ultrasound technology. To make up for the absence of conventional imaging, functional state evaluation of the motor system can offer conventional ultrasonic tissue elasticity and hardness data. The purpose of this study was to objectively quantify the soft tissue surrounding the shoulder joint of stroke patients with CRPS using ultrasonic elastic imaging and to determine the diagnostic usefulness of ultrasonic elastic imaging for CRPS in stroke in order to promote its usage in clinical practice. Patients diagnosed with CRPS following a stroke and admitted to the rehabilitation unit at Shanxi Bethune Hospital between January, 2021 to June, 2021 were included in the analysis. The control group consisted of people without pain in their shoulder joints. Each group consisted of 30 patients. A high-frequency wire array probe (frequency = 8-16 Hz) was employed in conjunction with an ultrasonic diagnostic apparatus. A quantitative analytic system determined Young's modulus of the tissue, while the tracking of the shear wave provided an elastin map in real-time. An excitation pulse of acoustic radiation force was used to cause shear waves in the tissue. The Young's modulus of supraspinatus muscle in the study and control groups was 289.16±22.07 Kpa and 231.99±23.61 Kpa, respectively (P <0.01). Young's modulus values of the study group's subscapular biceps were compared to those of the control group (P > 0.05). The supraspinatus shear wave elastographic (SWE) imaging value was 10.01±0.49 m/s in the study group and 7.92±0.50 in the control group (P <0.05). The study and control groups had subscapular muscle SWE values of 15.99±1.95 and 8.64±0.56 m/s, respectively (P <0.05). The average biceps tendon SWE value in the study and control groups was 6.39±0.42 and 4.69±0.36 m/s, respectively (P <0.05). In conclusion, the SWE assessed by ultrasound elastography is useful for early diagnosis and evaluation of the superior shoulder tendon, subscapular tendon, and biceps tendon of CRPS following stroke.

Potential predictive effect of mechanical properties of the plantar skin and superficial soft tissue, and vibration perception on plantar loading during gait in individuals with diabetes

BackgroundThis exploratory study aimed to investigate the extent to which mechanical properties of the plantar skin and superficial soft tissue (hardness, stiffness, and thickness) and vibration perception thresholds (VPTs) predict plantar pressure loading during gait in people with diabetes compared to healthy controls.MethodsMechanical properties, VPTs, and plantar loadings during gait at the heel and first metatarsal head (MTH) of 20 subjects with diabetes, 13 with DPN, and 33 healthy controls were acquired. Multiple regression analyses were used to predict plantar pressure peaks and pressure-time integrals at both locations based on the mechanical properties of the skin and superficial soft tissues and VPTs.ResultsIn the diabetes group at the MTH, skin hardness associated with 30-Hz (R2 = 0.343) and 200-Hz (R2 = 0.314) VPTs predicted peak pressure at the forefoot. In the controls at the heel, peak pressure was predicted by the skin thickness, hardness, and stiffness associated with 30-Hz (R2 = 0.269, 0.268, and 0.267, respectively) and 200-Hz (R2 = 0.214, 0.247, and 0.265, respectively) VPTs.ConclusionThe forefoot loading of people with diabetes can be predicted by the hardness of the skin when combined with loss of vibration perception at low (30-Hz) and high (200-Hz) frequencies. Further data from larger sample sizes are needed to confirm the current findings.

Comparison of Isolated or Combined Static Stretching and Foam Rolling on Knee Extensors' Function.

Static stretching (SS), foam rolling (FR), and a combination of both are used as warm-ups for sports and training. However, no reports have compared or examined the warm-up effects of short-term interventions (i.e., 30-s). Therefore, this study was designed to compare and examine the effects of short-term SS, FR, and SS+FR on knee extensors. The dominant knee extensors of 14 male university students (22.0 ± 1.3 years old) were tested. Five conditions were randomized: 60-s SS, 60-s FR, 30-s SS+ 30-s FR, 30-s SS, and 30-s FR to examine differences in intervention method, duration, and combined. The measures were knee flexion range of motion (ROM), pain pressure threshold (PPT), tissue hardness, maximum voluntary contraction-isometric (MVC-ISO), and MVC-concentric (MVC-CON) torques, measured before and after the intervention. Knee flexion ROM (d = 0.40, d = 0.59, d = 0.54, d = 0.59, d = 0.52 respectively) and PPT (d = 0.77, d = 0.60, d = 0.90, d = 0.74, d = 0.52, respectively) were significantly increased (p < 0.01), and tissue hardness (d = -0.79, d = -0.63, d = -0.53, d = -0.59, d = -0.72, respectively) was significantly decreased (p < 0.01) in all conditions. However, MVC-ISO decreased significantly (p < 0.01) in the 60-s SS and 30-s SS conditions but did not affect MVC-CON in all conditions. The results of this study revealed that SS, FR, and SS+FR interventions for a short-term as a warm-up before exercise were effective in increasing ROM, PPT, and decreasing tissue hardness. However, SS intervention with more than 30-s on the knee extensors decreased muscle strength, so short-term FR intervention is recommended when the goal is to increase ROM while maintaining both MVC-ISO and MVC-CON torques. Similarly, a short-term FR intervention after a short-term SS can eliminate the effect of strength impairments.

Increased tissue modulus and hardness in the TallyHO mouse model of early onset type 2 diabetes mellitus.

Individuals with type 2 diabetes mellitus (T2DM) have a higher fracture risk compared to those without T2DM despite having higher bone mineral density (BMD). Thus, T2DM may alter other aspects of resistance to fracture beyond BMD such as bone geometry, microarchitecture, and tissue material properties. We characterized the skeletal phenotype and assessed the effects of hyperglycemia on bone tissue mechanical and compositional properties in the TallyHO mouse model of early-onset T2DM using nanoindentation and Raman spectroscopy. Femurs and tibias were harvested from male TallyHO and C57Bl/6J mice at 26 weeks of age. The minimum moment of inertia assessed by micro-computed tomography was smaller (-26%) and cortical porosity was greater (+490%) in TallyHO femora compared to controls. In three-point bending tests to failure, the femoral ultimate moment and stiffness did not differ but post-yield displacement was lower (-35%) in the TallyHO mice relative to that in C57Bl/6J age-matched controls after adjusting for body mass. The cortical bone in the tibia of TallyHO mice was stiffer and harder, as indicated by greater mean tissue nanoindentation modulus (+22%) and hardness (+22%) compared to controls. Raman spectroscopic mineral:matrix ratio and crystallinity were greater in TallyHO tibiae than in C57Bl/6J tibiae (mineral:matrix +10%, p < 0.05; crystallinity +0.41%, p < 0.10). Our regression model indicated that greater values of crystallinity and collagen maturity were associated with reduced ductility observed in the femora of the TallyHO mice. The maintenance of structural stiffness and strength of TallyHO mouse femora despite reduced geometric resistance to bending could potentially be explained by increased tissue modulus and hardness, as observed at the tibia. Finally, with worsening glycemic control, tissue hardness and crystallinity increased, and bone ductility decreased in TallyHO mice. Our study suggests that these material factors may be sentinels of bone embrittlement in adolescents with T2DM.

Acute effect of short-term immobilization on lower leg muscle tissue hardness in healthy adults.

Previous studies have reported altered neural activity in the motor cortex after short-term cast immobilization, even in healthy participants. However, the effects of short-term movement restriction on tissue structure are not well understood. To investigate the effects of short-term lower limb immobilization on muscle tissue hardness. Seventeen healthy participants were enrolled in the study. Each participant's non-dominant lower limb was fixed with a soft bandage and medical splint for 10 h. Gastrocnemius muscle tissue hardness was measured using a tissue hardness meter before cast application and immediately after cast removal. Measurements were performed five times for each lower limb, and the three values with the lowest coefficient of variance were adopted as the value of muscle tissue hardness. Gastrocnemius muscle tissue hardness in the immobilized limb was lower after cast removal than that before cast application (from 53.6 to 51.8; p< 0.01), whereas the non-fixed limb showed an increase in muscle tissue hardness at the end of the experiment (from 52.9 to 54.3; p= 0.03). The findings indicate that 10 h movement restriction induced a reduction in muscle tissue hardness, suggesting acute adverse effects of cast immobilization for orthopedic treatment.

Comparison of Isolated or Combined Static Stretching and Foam Rolling on Knee Extensors’ Function

Static stretching (SS), foam rolling (FR), and a combination of both are used as warm-ups for sports and training. However, no reports have compared or examined the warm-up effects of short-term interventions (i.e., 30-s). Therefore, this study was designed to compare and examine the effects of short-term SS, FR, and SS+FR on knee extensors. The dominant knee extensors of 14 male university students (22.0 ± 1.3 years old) were tested. Five conditions were randomized: 60-s SS, 60-s FR, 30-s SS+ 30-s FR, 30-s SS, and 30-s FR to examine differences in intervention method, duration, and combined. The measures were knee flexion range of motion (ROM), pain pressure threshold (PPT), tissue hardness, maximum voluntary contraction-isometric (MVC-ISO), and MVC-concentric (MVC-CON) torques, measured before and after the intervention. Knee flexion ROM (d = 0.40, d = 0.59, d = 0.54, d = 0.59, d = 0.52 respectively) and PPT (d = 0.77, d = 0.60, d = 0.90, d = 0.74, d = 0.52, respectively) were significantly increased (p &lt; 0.01), and tissue hardness (d = -0.79, d = -0.63, d = -0.53, d = -0.59, d = -0.72, respectively) was significantly decreased (p &lt; 0.01) in all conditions. However, MVC-ISO decreased significantly (p &lt; 0.01) in the 60-s SS and 30-s SS conditions but did not affect MVC-CON in all conditions. The results of this study revealed that SS, FR, and SS+FR interventions for a short-term as a warm-up before exercise were effective in increasing ROM, PPT, and decreasing tissue hardness. However, SS intervention with more than 30-s on the knee extensors decreased muscle strength, so short-term FR intervention is recommended when the goal is to increase ROM while maintaining both MVC-ISO and MVC-CON torques. Similarly, a short-term FR intervention after a short-term SS can eliminate the effect of strength impairments.

Endoscopic Ultrasound (EUS) Guided Elastography.

Endoscopic ultrasound (EUS) is an essential technique for the management of several diseases. Over the years, new technologies have been developed to improve and overcome certain limitations related to EUS-guided tissue acquisition. Among these new methods, EUS-guided elastography, which is a real-time method for the evaluation of tissue stiffness, has arisen as one of the most widely recognized and available. At present, there are available two different systems to perform an elastographic evaluation: strain elastography and shear wave elastography. Strain elastography is based on the knowledge that certain diseases lead to a change in tissue hardness while shear wave elastography monitored shear-wave propagation and measures its velocity. EUS-guided elastography has shown in several studies high accuracy in differentiating benign from malignant lesions from many different locations, mostly in the pancreas and lymph nodes. Therefore, nowadays, there are well-established indications for this technology, mainly for supporting the management of pancreatic diseases (diagnosis of chronic pancreatitis and differential diagnosis of solid pancreatic tumors) and characterization of different diseases. However, there are more data on new potential indications for the near future. In this review, we will present the theoretical bases of this technology and we will discuss the scientific evidence to support its use.

The usefulness of transabdominal ultrasound elastography in Helicobacter pylori gastritis in children.

Helicobacter pylori can colonize the submucosal layer as well as the mucosa in the stomach. Inflammation and erosions cause both mucosal and submucosal thickening in patients with Helicobacter pylori gastritis. Elastography is a method for measuring the elasticity and hardness of tissues by visualization of their response to the applied force. Hard tissues respond to applied compression differently compared to soft tissues. Hard tissues displace as a whole without deforming as opposed to soft tissues. In this study, we investigated the diagnostic performance of transabdominal ultrasound elastography in detecting Helicobacter pylori gastritis in children. Nineteen children (group 1) with Helicobacter pylori gastritis, 33 children (group 2) with Helicobacter pylori (-) gastritis and 37 healthy children (group 3) were included the study. These groups were compared in terms of their strain index values. Ultrasonographic examinations were performed with a single transducer at 1.8-6.2 MHz frequency range. Both group 1 and 2 had significantly higher strain index values compared to the control group (2.7, 2.2 and 1.4 respectively). Additionally, the mean strain index value was significantly higher in group 1 compared to group 2. Transabdominal ultrasound elastography has diagnostic value in differentiating Helicobacter pylori (+) gastritis from Helicobacter pylori (-) gastritis as well as in the diagnosis of gastritis in children.

Clinical evaluation of a new hand-driven hysteroscopic tissue removal device, Resectr™ 5fr, for the resection of endometrial polyps in an office setting.

A first clinical evaluation of a new hand-driven hysteroscopic tissue removal device, Resectr™ 5fr, for office polypectomy without any anesthesia. Women with at least one small endometrial polyp were eligible. Hysteroscopic polypectomy was performed using the Resectr™ 5fr in an office setting, without any anesthesia. One hundred and two hysteroscopic polypectomies were included in the analysis. The median installation time was 1.9min (95% confidence interval (CI) 1.6-2.1). The median time to complete polyp removal was 1.2min (95% CI 0.8-1.6). The median surgeon's safety, practical, and comfort scores on a 5-point Likert scale were high (5 (5-5), 5 (4-5), and 5 (4-5), respectively). Women's pain score was low (median 1 (0-3)), whereas the satisfaction rate was high (median 5 (5-5)), both on a 5-point Likert scale. There were two conversions (hysteroscopic scissors (n = 1), a new Resectr™ 5fr device (n = 1)). There was one incomplete procedure (tissue hardness). Hysteroscopic removal of small polyps, using the [Formula: see text] 5fr in an office setting is feasible in terms of installation and resection time. Surgeon's practical, comfort, and safety scores are high, whereas women report low pain scores and high satisfaction rates. TRIAL REGISTRATION: Dutch Clinical Trial Registry (NTR 7119, NL6923): https://www.trialregister.nl/trial/6923 . Date of registration: 27/03/2018.

Fine Tuning of the Mechanical Properties of Bio-Based PHB/Nanofibrillated Cellulose Biocomposites to Prevent Implant Failure Due to the Bone/Implant Stress Shielding Effect

A significant mechanical properties mismatch between natural bone and the material forming the orthopedic implant device can lead to its failure due to the inhomogeneous loads distribution, resulting in less dense and more fragile bone tissue (known as the stress shielding effect). The addition of nanofibrillated cellulose (NFC) to biocompatible and bioresorbable poly(3-hydroxybutyrate) (PHB) is proposed in order to tailor the PHB mechanical properties to different bone types. Specifically, the proposed approach offers an effective strategy to develop a supporting material, suitable for bone tissue regeneration, where stiffness, mechanical strength, hardness, and impact resistance can be tuned. The desired homogeneous blend formation and fine-tuning of PHB mechanical properties have been achieved thanks to the specific design and synthesis of a PHB/PEG diblock copolymer that is able to compatibilize the two compounds. Moreover, the typical high hydrophobicity of PHB is significantly reduced when NFC is added in presence of the developed diblock copolymer, thus creating a potential cue for supporting bone tissue growth. Hence, the presented outcomes contribute to the medical community development by translating the research results into clinical practice for designing bio-based materials for prosthetic devices.