Objective To explore the components of passive movement resistance in the wrist flexor in subjects after stroke, and investigate the correlations between these components and clinical scales such as Modified Ashworth Scale (MAS) and Fugl-Meyer Assessment (FMA). Methods From March to August 2017, a cross-sectional study was performed in 15 stroke survivors in the Department of Rehabilitation Medicine, the First Affiliated Hospital, Sun Yat-sen University. MAS and FMA were assessed by an experienced physical therapist. Components of passive movement resistance in the flexors of wrist and finger were recorded by NeuroFlexor (Aggro MedTech AB, Solna, Sweden), then the average resisting force in one second ensued the passive stretch at 5°/s was took as peak resisting force (PRF). The PRF between paretic side and non-paretic side was compared. Spearman’s rank correlation was used to test the relation between the components and clinical scales. Results The PRF of the paretic side during the slow passive stretch (5°/s) was significantly higher than that of the non-paretic side [(10.49±1.65) vs. (8.98±1.11) N, P<0.05]. Correlations between MAS and the components/PRF were insignificant (P>0.05). FMA had a significant correlation with neural component of the paretic side (rs=–0.645, P=0.009). Conclusions The higher PRF of slow passive stretch in the paretic side may be attributed to the higher muscle stiffness. Neural component of the paretic wrist is correlated with FMA. These findings could be applied in clinical evaluation of functional performance of the wrist muscle of stroke survivors.
ObjectiveTo investigate the effectiveness of distraction therapy assisted by arthroscope in the treatment of ankle traumatic osteoarthritis. MethodsBetween October 2013 and October 2014, 13 patients with ankle traumatic osteoarthritis were treated, including 8 males and 5 females with an age range of 44-63 years (mean, 55.2 years). The left ankle and the right ankle were involved in 4 and 9 cases respectively. The disease duration was 1.5-10.0 years (median, 5 years). The American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hind foot scale score was 51.00±7.09; the short-form 36 health survey scale (SF-36) score was 40.82±4.62. According to Scranton grade system, 9 cases were rated as grade II and 4 cases as grade III. First, ankle hyperplasia osteophytes was removed under arthroscope, then Ilizarov apparatus was used to maintain distraction of 5-10 mm ankle space for 3 months. ResultsOne case had postoperative pin tract infection after removing the external fixation, and infection was controlled by dressing treatment; no related complications occurred in the other patients. All patients got follow-up of 12-18 months (mean, 14.7 months). Patients achieved disappearance of ankle swelling, pain relief, and were able to walk after rehabilitation. The ankle activity was obviously improved. At last follow-up, AOFAS ankel-hind foot scale score and SF-36 score were significantly increased to 85.23±6.41 and 56.29±6.20 respectively (t=20.756, P=0.025; t=11.647, P=0.018). According to AOFAS scores, the results were excellent in 4 cases, good in 8 cases, and fair in 1 case; the excellent and good rate was 92.3%. Postoperative X-ray film showed normal ankle position and alignment, osteophytes at the edges of the tibia and talus, articular surface sclerosis, normal joint space, and no joint swelling. ConclusionDistraction therapy assisted by arthroscope is an effective method for treating ankle traumatic osteoarthritis.
Bone marrow-derived mesenchymal stem cells (BMSCs) are multipotent stem cells that differentiate into a variety of cell types and widely used in tissue regeneration engineering. The purpose of this study is to investigate whether the cyclic biaxial stretching strain could promote the rat BMSCs (rBMSCs) to differentiate into cardiomyocyte-like cells in vitro. The second or third generation of rBMSCs were randomly divided into the cyclic stretching stain group, the control group and the blank group. Those rBMSCs in the cyclic stretching strain group were seeded on a silicone membrane with complete medium were exposed to biaxial stretching strain of 10% of membrane at a frequency of 1 Hz lasting for 6 h, 12 h and 24 h. Those in the control group were seeded on silicone membrane with complete medium. Those in the blank group were seeded in the 6-wells plates with complete medium. The mRNA expression of GATA4 and myocyte-specific enhancer factor 2C (MEF-2C) were detected by the real-time fluorescent quantification PCR and the protein expression of connexin 43 (Cx43) was detected by using the Western blot method. The results showed that the mRNA expression level of the GATA4 and MEF-2C, and the protein expression level of Cx43 were significantly higher in the cyclic stretching strain groups, compared with those in the relative control groups (P<0.05). It suggests that cyclic biaxial stretching strain could play a part in the induction of rBMSCs to differentiate into cardiomyocyte-like cells in vitro, but the differentiation mechanism is still unclear.
OBJECTIVE: To investigate the availability and effect of skin stretch in closing the firearm injured soft tissue defect. METHODS: Eight white pigs with firearm injured soft tissue defect were divided into 3 groups. Each group I and group II had 3 pigs which were performed skin stretch. The control group had 2 pigs without stretch. The average diameter of the defect in three groups was (7.3 +/- 0.2) cm, (9.1 +/- 0.3) cm, (7.3 +/- 0.2) cm respectively, and the site of defect was on the lateral thigh and buttock. RESULTS: Skin stretch could make a visible reduction of the wound. It was possible to close the wound by direct traction when the diameter of the buttock wound was less than 7 cm, and when the diameter of the lateral thigh wound was less than the radius of thigh. The skin stretch should not last more than 7 days and the best effect appeared in 4 to 5 days after performing the skin stretch. CONCLUSION: The skin stretch can be applied in the repair of the firearm injured soft tissue defect. It has many advantage compared with the tradtional treatment.
Objective To investigate the application of modified adjustable skin stretching and secure wound-closure system in repairing of skin and soft tissue defect. Methods Between March 2016 and April 2017, 21 cases of skin and soft tissue defects were repaired with the modified adjustable skin stretching and secure wound-closure system (the size of regulating pressure and the times of adjustment were determined according to the color, temperature, capillary response, and swelling degree of the skin edge). There were 11 males and 10 females, with an average age of 49.2 years (range, 21-67 years). Among them, 1 case was the residual wound after amputation of leg; 18 cases were the wounds after traumatic injury operation, including 4 cases in the lower leg, 3 cases in the knee joint, 7 cases in the upper limb, and 4 cases in the foot; and 2 cases were diabetic feet. The skin defect area ranged from 4.0 cm×2.5 cm to 21.0 cm×10.0 cm. Results Skin defect wounds closed directly in one stage in 4 cases; 12 cases were closed after continuously stretching for 5-14 days (mean, 10 days); 5 cases were reduced to less than one-half area, and the wound healed after the second skin grafting or flap repairing. All the 21 patients were followed up 3-12 months (mean, 5.2 months). The wound was linear healing with small scar, and no invasive margin, poor blood flow, necrosis, and poor sensory function happened. Conclusion The modified adjustable skin stretching and secure wound-closure system can reduce the skin and soft tissue defects or close the wound directly, and even replace the skin graft and skin flap repairing. It was a good method for the treatment of skin and soft tissue defect.
ObjectiveTo investigate the effectiveness of channel screw combined with skin-stretching technique in treatment of pelvic fracture with severe Morel-Lavallée lesion.MethodsBetween January 2017 and May 2020, 11 patients with pelvic fractures complicated with severe Morel-Lavallée lesions were treated with channel screw combined with skin-stretching technique. There were 8 males and 3 females, with an average age of 39.2 years (range, 28-58 years). Causes of injury included traffic accident in 9 cases and falling from hight in 2 cases. The time from injury to hospital admission ranged from 1 to 6 days (mean, 3.7 days). According to the Tile classification, the pelvic fractures were rated as type C1 in 7 cases, type C2 in 3 cases, and type C3 in 1 case. The sites of Morel-Lavallée lesions were buttocks in 8 cases, hips in 2 cases, and thigh in 1 case. There was 1 case of rectal injury, 1 case of splenic rupture, 3 cases of craniocerebral injury, 2 cases of chest injury, 4 cases of spinal fracture, and 6 cases of sacral nerve injury. X-ray films were performed to observe reduction and healing of fracture. The quality of fracture reduction was evaluated by Matta standard at 1 week after operation. Wound healing and complications were observed. Majeed scoring was used to evaluate hip function and Gibbons sacral nerve injury grading was used to evaluate neurological function recovery.ResultsThe patients underwent 4-7 operations, with an average of 5.8 operations. The time of first operation (pelvic fracture fixation, debridement, and skin distractor installation) was 115-275 minutes, with an average of 186.5 minutes. The amount of intraoperative blood loss was 30-80 mL, with an average of 45.5 mL. All patients were followed up 6-12 months, with an average of 8.3 months. The quality of fracture reduction according to the Matta standard was excellent in 7 cases, good in 2 cases, and fair in 2 cases, with an excellent and good rate of 81.8%. All fractures healed at 3-6 months after operation, with an average of 4.5 months. At last follow-up, the hip functions were excellent in 7 cases and good in 4 cases according to Majeed scoring, with an excellent and good rate of 100%. Among the 6 patients complicated with sacral nerve injury, the Gibbons sacral nerve injury grading reached gradeⅠ for 4 cases, gradeⅡ for 1 case, and grade Ⅲ for 1 case. The wounds of 9 cases were sutured directly after skin-stretching treatment for 25-32 days, with an average of 28 days. The dermal edge necrosis occurred in 1 case, and the defect was repaired by free skin grafting. The skin superficial dry necrosis of the wound occurred in 1 case, and healed by dressing change.ConclusionIn the treatment of pelvic fracture complicated with severe Morel-Lavallée lesion, the channel screw and skin-stretching technique showed their own advantages, which can obtain early fracture fixation and good wound healing.
This study is aimed to investigate the effects of mechanical stretch on the expression of transforming growth factor-β1 (TGF-β1) and fibroblast growth factor-2 (FGF-2), and the signaling pathway in human bronchial epithelioid (16HBE) cells under mechanical stretch. Using loading device with flexible substrate (FX-4000T) to stretch 16HBE cells, we found that the stretching elongation was 15%, at frequency of 1 Hz, stretching for 0.5 h, 1 h, 1.5 h and 2 h. Choosing the higher expression of TGF-β1, FGF-2 and Ca2+ group to carry out intervention experiments, we used the cells pretreated with canonical transient receptor potential 1 (TRPC1) channel antagonist SKF96365, protein kinase C (PKC) inhibitor HA-100, and thereafter mechanical stretch to interpose. Compared with those in the blank control group, TGF-β1 and FGF-2' protein and mRNA, intracellular Ca2+ fluorescence intensity were higher, and the differences were statistically significant (P < 0.05) at the 4 time points, 0.5 h, 1 h, 1.5 h and 2 h. At 0.5 h, the increasing rate was the highest. TGF-β1 protein and mRNA, FGF-2 protein and mRNA, intracellular Ca2+ luorescence intensity in the stretch+SKF96365 and stretch+HA-100 intervented group were decreased, the differences were statistically significant than those in 0.5 h stretch group (P < 0.05) without intervention. The expression of TGF-β1, FGF-2 was up-regulated in 16HBE cells under mechanical stretch, PKC, TRPC1, and Ca2+ may participate in the signal path.
Objective To investigate whether mechanical stretch stimulation affects the expression of the immediate early gene c-fos mRNA in rat Achilles-derived tendon stem cells (TSCs)in vitro. Methods TSCs were isolated from the Achilles tendons of 8 weeks old male Sprague Dawley rats by enzymatic digestion method and cultured for 3 passages. The TSCs were stimulated by a uniaxial cyclic stretching loading system under the condition of 1 Hz, respectively with 4% or 8% stretch intensity for 0, 5, 15, 30, 60, and 120 minutes. At each time point, TSCs were collected to detect c-fos mRNA expressions and to find the best time-point Tmax by real-time fluorescence quantitative PCR. Then, TSCs were simulated with 2%, 4%, 6%, 8%, or 12% stretch intensity for Tmax to observe the relative expressions of c-fos mRNA under different stretch intensities. Next, TSCs were stretched for 0, 5, or 15 minutes respectively and followed by incubation at relax status up to Tmax to observe the changes of c-fos mRNA expressions after short period stimulation. Finally, TSCs were stimulated with 4% or 8% stretch intensity respectively for 0, Tmax, or 120 minutes to detect the expressions of the tenogenic differentiation related genes [collagen type I, tenomodulin (TNMD)], the osteogenic differentiation related genes [runt related transcription factor 2 (Runx2), distal-less homeobox 5 (Dlx5)], and the adipogenic differentiation related gene [fatty acid binding protein 4 (FABP4)]. Results Under 4% or 8% stretch intensity, the relative expressions of c-fos mRNA significantly increased at 15 minutes (P<0.05), reached the maximum at 30 minutes (P<0.05), and returned to baseline at 60 minutes (P>0.05) when compared with expression at 0 minute. Therefore, Tmax was 30 minutes. The stretch intensity of 2% was enough to cause the expression of c-fos mRNA at 30 minutes, and the expression was significantly higher under the stretch intensity of 6%, 8%, and 12% than 2% and 4% (P<0.05). Even for a short period stimulation of 5 minutes, c-fos mRNA expression could still significantly increase at 30 minutes (P<0.05). The relative expressions of differentiation related genes at 30 and 120 minutes showed no significant difference when compared with the expression at 0 minute under 4% stretch intensity (P>0.05); but the relative expression of Runx2 gene significantly increased at 30 minutes, and the relative expressions of collagen type I, TNMD, Dlx5, and Runx2 increased at 120 minutes under 8% stretch intensity (P<0.05). Conclusion Mechanical stretch stimulation can affect the relative expression of the immediate early gene c-fos mRNA of rat Achilles-derived tendon stem cellsin vitro, and there is time- and intensity-dependence. It is suggested that the mechanical stimulation with different time or intensity may affect the differentiation of TSCs at early stage. This study is meaningful for the further study on TSCs intracellular mechanical signal transfer mechanism.
Idiopathic pulmonary fibrosis (IPF) is a progressive scar-forming disease with a high mortality rate that has received widespread attention. Epithelial mesenchymal transition (EMT) is an important part of the pulmonary fibrosis process, and changes in the biomechanical properties of lung tissue have an important impact on it. In this paper, we summarize the changes in the biomechanical microenvironment of lung tissue in IPF-EMT in recent years, and provide a systematic review on the effects of alterations in the mechanical microenvironment in pulmonary fibrosis on the process of EMT, the effects of mechanical factors on the behavior of alveolar epithelial cells in EMT and the biomechanical signaling in EMT, in order to provide new references for the research on the prevention and treatment of IPF.
ObjectiveTo investigate the utility of stretched exponential model diffusion-weighted imaging (DWI) for diagnosing of advanced liver fibrosis.MethodsThe patients with chronic liver disease complicated with vary degrees of fibrosis confirmed by pathological examination underwent DWI using different b-values (0, 50, 600 s/mm2) at the First Affiliated Hospital of Chengdu Medical College from June 2015 to February 2020 were collected. In addition, patients who underwent upper abdominal MRI examination in the same hospital at the same time and had no liver disease or disease affecting liver function were collected as a control group. The apparent diffusion coefficient (ADC) was calculated by using a mono-exponential model. The distributed diffusion coefficient (DDC) and water molecular diffusion heterogeneity index (α) were calculated by using a stretched exponential model. The fibrosis stage was evaluated by using the Metavir scoring system. The ADC, DDC, and α among different fibrosis groups were compared. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic efficacy of these three quantitative parameters for advanced liver fibrosis.ResultsA total of 42 patients with chronic liver disease were collected in this study, including mild liver fibrosis (S1–S2, n=16) and advanced liver fibrosi (≥S3, n=24); 15 patients in the control group. The values of ADC, DDC, and α of the patients with mild liver fibrosis and advanced liver fibrosis were significantly lower than those of the control patients (P<0.05). The area under the ROC curve of ADC, DCC, and α in diagnosing liver fibrosis (≥S1) was 0.915, 0.974, and 0.835, respectively, which in diagnosing advanced liver fibrosis (≥S3) was 0.744, 0.869, and 0.758, respectively. However, further the area under ROC curve among these three metrics had no statistical differences (P>0.05).ConclusionDDC based on stretched exponential model is valuable for diagnosis of advanced liver fibrosis.