Lidocaine inhibits migration of tenocytes by downregulating focal adhesion kinase and paxillin phosphorylation

Lidocaine is the most frequently applied local infiltration anesthetic agent for treating tendinopathies. However, studies have discovered lidocaine to negatively affect tendon healing. In the current study, the molecular mechanisms and effects of lidocaine on tenocyte migration were evaluated. We treated tenocytes intrinsic to the Achilles tendons of Sprague-Dawley rats with lidocaine. The migration ability of cells was analyzed using electric cell-substrate impedance sensing (ECIS) and scratch wound assay. We then used a microscope to evaluate the cell spread. We assessed filamentous actin (F-actin) cytoskeleton formation through immunofluorescence staining. In addition, we used Western blot analysis to analyze the expression of phospho-focal adhesion kinase (FAK), FAK, phospho-paxillin, paxillin, and F-actin. We discovered that lidocaine had an inhibitory effect on the migration of tenocytes in the scratch wound assay and on the ECIS chip. Lidocaine treatment suppressed cell spreading and changed the cell morphology and F-actin distribution. Lidocaine reduced F-actin formation in the tenocyte during cell spreading; furthermore, it inhibited phospho-FAK, F-actin, and phospho-paxillin expression in the tenocytes. Our study revealed that lidocaine inhibits the spread and migration of tenocytes. The molecular mechanism potentially underlying this effect is downregulation of F-actin, phospho-FAK, and phospho-paxillin expression when cells are treated with lidocaine.

Leukocyte-poor platelet-rich plasma and leukocyte-rich platelet-rich plasma promote myoblast proliferation through the upregulation of cyclin A, cdk1, and cdk2

Muscle injuries are common among athletes and often treated with platelet-rich plasma (PRP). However, whether the leukocyte concentration affects the efficacy of PRP in treating muscle injuries remains unclear. This study investigated the effects of leukocyte-poor platelet-rich plasma (LP-PRP) and leukocyte-rich platelet-rich plasma (LR-PRP) on myoblast proliferation and the molecular mechanisms underlying these effects. Myoblasts were treated with 0.5% LP-PRP, 0.5% LR-PRP, 1% LP-PRP, or 1% LR-PRP for 24 h. The gene expression of the LP-PRP- and LR-PRP-treated myoblasts was determined using RNA sequencing analysis. Cell proliferation was evaluated using an bromodeoxyuridine (BrdU) assay, and cell cycle progression was assessed through flow cytometry. The expression of cyclin A, cyclin-dependent kinase 1 (cdk1), and cdk2 was examined using Western blotting. The expression of myoblast determination protein 1 (MyoD1) was examined through Western blotting and immunofluorescence staining. The LP-PRP and LR-PRP both promoted the proliferation of myoblasts and increased differential gene expression of myoblasts. Moreover, the LP-PRP and LR-PRP substantially upregulated the expression of cyclin A, cdk1, and cdk2. MyoD1 expression was induced in the LP-PRP and LR-PRP-treated myoblasts. Our results corroborate the finding that LP-PRP and LR-PRP have similar positive effects on myoblast proliferation and MyoD1 expression.

Animal naming test is a simple and valid tool for detecting covert hepatic encephalopathy and predicting outcomes in Chinese-speaking regions: a preliminary study

BACKGROUND AND AIMS

Hepatic encephalopathy (HE) implies high morbidity and mortality. The assessment of covert HE (CHE) [i.e. minimal HE (MHE) plus grade 1 HE] is often neglected in Taiwan. Therefore, the aim was to investigate the potential of the animal naming test (ANT1 and simplified ANT1 (S-ANT1)) for assessing CHE in Chinese-speaking regions, specifically Taiwan.

METHODS

A prospective cohort study was conducted, comprising 65 cirrhotic patients and 29 healthy controls (relatives of the patients). Patients were followed up every three months and censored after two years or until death. Hospitalization for overt HE (OHE) and mortality were considered. All subjects underwent ANT1, psychometric HE score (PHES), and mini-mental state examination (MMSE). The patients underwent an electroencephalogram (EEG) to detect slowing indicative of MHE. Cut-off values for ANT1 and S-ANT1 were assessed by ROC analysis and Youden's index, considering CHE as a reference. The prognostic values for OHE and OHE-free survival were assessed.

RESULTS

Preliminary analysis confirmed that PHES ≤-4 is a good discriminant point for abnormal results. CHE was found in 29 patients: 9 had MHE (PHES ≤ -4 or altered EEG) and 20 had grade 1 HE. ANT1 and S-ANT1 were found to have diagnostic values for CHE: AUC = 0.807, 0.786; cut off: 18 and 19, respectively. ANT1 and S-ANT1 were found to have prognostic value for OHE, number of hospitalization episodes for OHE, and OHE recurrence-free survival.

CONCLUSIONS

ANT1 shows promise as a tool for CHE detection, quantification, and follow-up in Taiwan and other Chinese-speaking regions.Key messagesThe animal naming test (ANT1) is a simple and valid semantic fluency test that can be easily performed in outpatient or bedside settings in one minute and can also be used as a tool for covert hepatic encephalopathy (CHE) detection, quantification, and follow-up in Taiwan, other Chinese-speaking regions, and many other countries.The diagnostic value of ANT1 and S-ANT1 for CHE were found to be significant, with area under the receiver operating characteristic curve (AUROC) values of 0.807 and 0.786 respectively, and cut-off scores of 18 and 19.ANT1 and S-ANT1 have prognostic value for the first breakthrough of overt hepatic encephalopathy (OHE), number of hospitalization episodes for OHE, and OHE recurrence-free survival, independent of the MELD score.

The effectiveness of eHealth interventions on moderate-to-vigorous intensity physical activity among cardiac rehabilitation participants: a systematic review and meta-analysis

Background

Cardiac rehabilitation is a class IA recommendation for patients with cardiovascular diseases. Physical activity is the core component and core competency of cardiac rehabilitation programs. Cardiac rehabilitation guidelines recommend patients achieve at least thirty minutes of moderate-to-vigorous intensity physical activity five or more days per week. However many patients with cardiovascular diseases are failing to meet recommended daily physical activity levels. eHealth interventions may increase moderate-to-vigorous intensity physical activity among cardiac rehabilitation participants.

Objectives

The objective of this study was to review the evidence of the effectiveness of eHealth interventions to increase moderate-to-vigorous intensity physical activity among cardiac rehabilitation participants. The secondary objective was to examine the effectiveness of eHealth interventions on improving exercise capacity, cardiovascular risk profile and health-related quality of life.

Methods

A comprehensive search strategy was developed for four electronic databases (PubMed, Web of Science, Embase and The Cochrane Library); through December 16, 2021. All studies reporting on eHealth interventions designed to increase moderate-to-vigorous physical activity among cardiac rehabilitation participants were included. Multiple not-blind reviewers determined study eligibility and extracted data. Risk of bias was evaluated using the Cochrane Collaboration Tool for randomized controlled trials and using the Effective Practice and Organisation of Care Cochrane Review Group for non-randomized controlled trials. Data quality using the Grading of Recommendations Assessment, Development and Evaluation professional guideline development tool. Data were pooled using a random-effects model. All statistical analyses were performed using Stata 17.

Results

Twenty-one studies were included in the review which fifteen were in the meta-analysis. The meta-analysis demonstrated eHealth interventions improved moderate-to-vigorous physical activity (standard mean difference = 0.17, 95% confidence interval: 0.07, 0.27, P<0.001). No changes were observed in exercise capacity (P=0.09), cardiovascular risk profile (body mass index, P=0.19; waist circumference, P=0.7; systolic blood pressure, P=0.36; total cholesterol, P=0.72; plasma glucose, P=0.41) and health-related quality of life (P=0.12).

Conclusions

eHealth interventions are effective at increasing minutes/week of moderate-to-vigorous intensity physical activity among cardiac rehabilitation participants. Future high-quality empirical studies are needed to evaluate the effectiveness of eHealth interventions delivered, with these sub-types (wearable devices, online web portal, smart phone application, messaging services and telephone calls) delivered alone or in combination delivered more conducive to moderate-to-high intensity physical activity.

Funding Acknowledgement

Type of funding sources: None.

Lidocaine Inhibited Tendon Cell Proliferation and Extracellular Matrix Production by Down Regulation of Cyclin A, CDK2, Type I and Type III Collagen Expression

Lidocaine injection is a common treatment for tendon injuries. However, the evidence suggests that lidocaine is toxic to tendon cells. This study investigated the effects of lidocaine on cultured tendon cells, focusing on the molecular mechanisms underlying cell proliferation and extracellular matrix (ECM) production. Tendon cells cultured from rat Achilles tendons were treated with 0.5, 1.0, or 1.5 mg/mL lidocaine for 24 h. Cell proliferation was evaluated by Cell Counting Kit 8 (CCK-8) assay and bromodeoxyuridine (BrdU) assay. Cell apoptosis was assessed by Annexin V and propidium iodide (PI) stain. Cell cycle progression and cell mitosis were assessed through flow cytometry and immunofluorescence staining, respectively. The expression of cyclin E, cyclin A, cyclin-dependent kinase 2 (CDK2), p21, p27, p53, matrix metalloproteinases-2 (MMP-2), matrix metalloproteinases-9 (MMP-9), type I collagen, and type III collagen were examined through Western blotting, and the enzymatic activity of MMP-9 was determined through gelatin zymography. Lidocaine reduced cell proliferation and reduced G1/S transition and cell mitosis. Lidocaine did not have a significant negative effect on cell apoptosis. Lidocaine significantly inhibited cyclin A and CDK2 expression but promoted p21, p27, and p53 expression. Furthermore, the expression of MMP-2 and MMP-9 increased, whereas that of type I and type III collagen decreased. Lidocaine also increased the enzymatic activity of MMP-9. Our findings support the premise that lidocaine inhibits tendon cell proliferation by changing the expression of cell-cycle-related proteins and reduces ECM production by altering levels of MMPs and collagens.

On-site Ultrasound Screens out Asymptomatic Knee Lesions in Elite Adolescent Male Basketball Players

Basketball is a popular sport worldwide with a high injury risk. In this study, we conducted survey composed of clinical symptom reporting scale, physical examination and meticulous portable musculoskeletal ultrasound to 19 elite male high school basketball players and 15 regular male high school students. Our study showed the incidence of ultrasonographic findings of any lesion, suprapatellar effusion and proximal patellar tendinopathy is significantly higher in player group, and the incidence of asymptomatic ultrasonographic lesion is also higher in player group. Screening for asymptomatic lesions bares clinical relevance and plays a role in prevention of symptom development. With the concise and easy-to-perform ultrasonography protocol we performed and being interpreted by sports team physician, the protocol can offer precise diagnosis of common injury and screening for asymptomatic lesion potentially progressive.

Use of Platelet-Rich Plasma Plus Suramin, an Antifibrotic Agent, to Improve Muscle Healing After Injuries

BACKGROUND

The increasing use of platelet-rich plasma (PRP) to treat muscle injuries raises concerns because transforming growth factor-beta (TGF-β) in PRP may promote fibrosis in the injured muscle and thus impair muscle regeneration.

PURPOSE

To investigate whether suramin (a TGF-β inhibitor) can reduce muscle fibrosis to improve healing of the injured muscle after PRP treatment and identify the underlying molecular mechanism.

STUDY DESIGN

Controlled laboratory study.

METHODS

Myoblasts isolated from the gastrocnemius muscle of Sprague Dawley rats were treated with PRP or PRP plus suramin. MTT assays were performed to evaluate cell viability. The expression of fibrosis-associated proteins (such as type I collagen and fibronectin), Smad2, and phosphorylated Smad2 was determined using Western blot analysis and immunofluorescent staining. An anti-TGF-β antibody was employed to verify the role of TGF-β in fibronectin expression. Gastrocnemius muscles were injured through a partial transverse incision and then treated using PRP or PRP plus suramin. Hematoxylin and eosin staining was conducted to evaluate the healing process 7 days after the injury. Immunofluorescent staining was performed to evaluate fibronectin expression. Muscle contractile properties-fast-twitch and tetanic strength-were evaluated through electric stimulation.

RESULTS

PRP plus 25 μg/mL of suramin promoted myoblast proliferation. PRP induced fibronectin expression in myoblasts, but suramin reduced this upregulation. The anti-TGF-β antibody also reduced the upregulation of fibronectin expression in the presence of PRP. The upregulation of phosphorylated Smad2 by PRP was reduced by either the anti-TGF-β antibody or suramin. In the animal study, no significant difference was discovered in muscle healing between the PRP versus PRP plus suramin groups. However, the PRP plus suramin group had reduced fibronectin expression at the injury site. Fast-twitch strength and tetanic strength were significantly higher in the injured muscle treated using PRP or PRP plus suramin.

CONCLUSION

Simultaneous PRP and suramin use reduced fibrosis in the injured muscle and promoted healing without negatively affecting the muscle's contractile properties. The underlying molecular mechanism may be associated with the phosphorylated Smad2 pathway.

CLINICAL RELEVANCE

Simultaneous PRP and suramin use may reduce muscle fibrosis without compromising muscle contractile properties and thus improve muscle healing.

Platelet-Rich Plasma Releasate Promotes Early Healing in Tendon After Acute Injury

Background

Acute tendon injury can limit motion and thereby inhibit tendon healing. Positive results have been found after the use of platelet-rich plasma (PRP) to treat tendon injury; however, the early effects of PRP on tendon regeneration are not known.

Purpose/Hypothesis

The purpose of this study was to evaluate the effects of PRP releasate (PRPr) on the early stages of tendon healing in a rat partial tenotomy model. It was hypothesized that PRPr can promote early healing of an Achilles tendon in rats.

Study Design

Controlled laboratory study.

Methods

PRP was prepared by a 2-step method of manual platelet concentration from 10 rats. PRPr was isolated from the clotted preparation after activation by thrombin and was applied to an Achilles tendon on 1 side of 30 rats on the second day after partial tenotomy, with normal saline used as the control on the other side. Achilles tendon samples were harvested 5 and 10 days after tenotomy. At each time point, 15 Achilles tendon samples were obtained, of which 5 samples were evaluated by Masson trichrome staining, apoptosis, and cell proliferation, while the other 10 samples were tested for tensile strength using a material testing machine.

Results

Compared with saline-treated control tendons, the PRPr-treated tendons showed increased collagen synthesis near the cut edge and fewer apoptotic cells (P = .01). An immunohistochemical analysis revealed more Ki-67-positive cells but fewer cluster of differentiation (CD) 68⁺ (ED1⁺) macrophages in PRPr tendons compared with saline-treated tendons (P < .01). Tendons treated with PRPr also showed higher ultimate tensile strength than those treated with saline (P = .03).

Conclusion

PRPr treatment promotes tissue recovery in the early phase of tendon healing by stimulating tendon cell proliferation and collagen production while inhibiting cell apoptosis and CD68⁺ (ED1⁺) macrophage infiltration.

Clinical Relevance

These findings suggest that with PRPr treatment, higher loads can be applied to the healing tendon at an earlier time, which can help the patient resume activity earlier.

[Short-term efficacy of robotic-assisted total mesorectal excision with and without lateral lymph node dissection for mid-low advanced rectal cancer: a propensity score matching analysis]

Objective: To evaluate the feasibility, safety and efficacy of robotic-assisted lateral lymph node dissection for mid-low advanced rectal cancer. Methods: A retrospective cohort study was performed. Inclusion criteria: (1) age between 18 and 80 years old; (2) rectal adenocarcinoma diagnosed by pathology; (3) without distant metastasis by preoperative CT or MRI; (4) patients underwent robotic-assisted total mesorectal resection (TME). Exclusion criteria: (1) conversion to open surgery; (2) multiple primary tumors; (3) patients underwent combined multiple organ resection. According to the above criteria, 137 patients undergoing robotic-assisted mid-low rectal cancer resection in the First Affiliated Hospital of Xi'an Jiaotong University from December 2016 to April 2019 were enrolled. Ninety-seven cases underwent robotic-assisted total mesorectal excision (TME group) and 40 underwent robotic-assisted total mesorectal resection with lateral lymph node dissection (LLND) (TME+LLND group, pelvic LLND was performed with neurovascular guidance to retain pelvic autonomic nerves in the order of the left side the first and then the right side). The propensity score matching of 1:1 was performed with R software, based on age, sex, BMI, ASA classification, distance from tumor to the anal verge, preoperative chemoradiotherapy history, preoperative abdominal surgery history, the size of tumors and TNM stage. The operative indicators, postoperative recovery, pathology and postoperative complications within 30 days were compared between the two groups. Results: A total of 72 cases were successfully matched (36 in each group), and there were no statistically significant differences in baseline data between the two groups (all P>0.05). The operation time of TME+LLND group was significantly longer than that of TME group [275.0 (180-405) minutes vs. 220.0 (140-320) minutes, Z=-3.680, P<0.001], while there were no statistically significant differences in blood loss during operation, time to postoperative first flatus, postoperative hospital stay, total hospital cost, tumor differentiation, and distal resection length of margin (all P>0.05). Circumferential resection margin was all negative in both groups. The number of harvested lymph modes in the TME+LLND groups was higher than that in the TME group [26 (18-37) vs. 14 (9-36), Z=-6.407, P<0.001]. In addition, there were no statistically significant differences in postoperative morbidity and Clavien-Dindo classification of complication within 30 days between the two groups (both P>0.05). Conclusions: Although robotic lateral lymph node dissection requires longer operation time, it is a feasible, safe and effective procedure.

Deformation of coracoacromial ligament during overhead movement as an early indicator of subacromial impingement in elite adolescent badminton players

Objectives: Deformation of the coracoacromial ligament during overhead movement has been linked to shoulder pathologies such as impingement and rotator cuff tear. We, therefore, explored this relationship in a group of elite adolescent badminton players.Method: We performed bilateral shoulder physical and ultrasonographic examination in 35 adolescent asymptomatic badminton players, 13 players with unilateral shoulder pain, and 15 non-athletes of similar age. Coracoacromial ligament deformation, defined as the maximal vertical distance between the ligament apex to a line connecting the acromion and coracoid process, was measured during shoulder abduction and internal rotation and compared within and between groups. Other ultrasonographic measurements and the incidence of shoulder pathologies were also evaluated.Result: Among badminton athletes who reported dominant shoulder pain, coracoacromial ligament deformation was significantly larger in their dominant shoulder than in their non-dominant shoulder (3.5 and 2.0 mm, respectively; p = 0.013); this difference was not present in other groups. Regardless of the presence or absence of pain, athletes displayed more coracoacromial ligament deformation and increased supraspinatus tendon thickness in their dominant shoulder than did the control group. Abnormal ultrasound findings were noted in all groups; however, the incidence was not significantly different.Conclusion: Increased coracoacromial ligament deformation during overhead movement is associated with shoulder pain in elite adolescent badminton players. Our findings may help clinicians identify athletes at risk of subacromial impingement syndrome.

Ibuprofen inhibited migration of skeletal muscle cells in association with downregulation of p130cas and CrkII expressions

Background

Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat sports-related muscle injuries. However, NSAIDs were recently shown to impede the muscle healing process after acute injury. Migration of skeletal muscle cells is a crucial step during the muscle healing process. The present study was performed to investigate the effect and molecular mechanisms of action of ibuprofen, a commonly used NSAID, on the migration of skeletal muscle cells.

Methods

Skeletal muscle cells isolated from the gastrocnemius muscle of Sprague-Dawley rats were treated with ibuprofen. MTT assay (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) was used to evaluate cell viability, and cell apoptosis was evaluated by TUNEL assay, after ibuprofen treatment. Skeletal muscle cell migration and spreading were evaluated using the transwell filter migration assay and F-actin staining, respectively. The protein expression of p130cas and CrkII, which are cell migration facilitating genes, was determined by western blot analysis. The overexpression of p130cas of muscle cells was achieved by p130cas vector transfection.

Results

The results demonstrated that ibuprofen did not have a significant negative effect on cell viability and apoptosis. Ibuprofen inhibited the migration and spreading of skeletal muscle cells in a dose-dependent manner. Ibuprofen also dose-dependently decreased the protein expression of p130cas and CrkII. Furthermore, overexpression of p130cas resulted in the promotion of cell migration and spreading and counteracted ibuprofen-mediated inhibition.

Conclusion

This study suggested that ibuprofen exerts a potentially adverse effect on the migration of skeletal muscle cells by downregulating protein expression of p130cas and CrkII. These results indicate a possible mechanism underlying the possible negative effect of NSAIDs on muscle regeneration.

Platelet-Rich Plasma Releasate Promotes Regeneration and Decreases Inflammation and Apoptosis of Injured Skeletal Muscle

BACKGROUND

Platelet-rich plasma (PRP) contains various cytokines and growth factors that may be beneficial to the healing process of injured muscle. Based on the authors' previous study, PRP releasate can promote proliferation and migration of skeletal muscle cells in vitro, so animal studies are performed to support the use of PRP to treat muscle injury in vivo.

PURPOSE

To investigate the effect of PRP releasate on regeneration of injured muscle, as well as its effect on inflammatory reaction and cell apoptosis, in the early stages of the muscle-healing process.

STUDY DESIGN

Controlled laboratory study.

METHODS

The gastrocnemius muscles of Sprague-Dawley rats were injured by partial transverse incision and then treated with PRP releasate. Hematoxylin and eosin stain was used to evaluate the healing process of injured muscle at 2, 5, and 10 days after injury. TUNEL assay was used to evaluate the cell apoptosis of injured muscle after PRP releasate treatment. Immunohistochemistry was used to stain the CD68-positive cells during the healing process. Muscle contractile properties, including fast-twitch and tetanic strength, were evaluated by electric stimulation.

RESULTS

The results revealed that PRP releasate treatment could enhance the muscle-healing process and decrease CD68-positive cells and apoptotic cells. Furthermore, the tetanic strength was significantly higher in injured muscle treated with PRP releasate.

CONCLUSION

In conclusion, PRP releasate could enhance the healing process of injured muscle and decrease inflammatory cell infiltration as well as cell apoptosis.

CLINICAL RELEVANCE

PRP promotes skeletal muscle healing in association with decreasing inflammation and apoptosis of injured skeletal muscle. These findings provide in vivo evidence to support the use of PRP to treat muscle injury.

Platelet rich plasma promotes skeletal muscle cell migration in association with up-regulation of FAK, paxillin, and F-Actin formation

Platelet rich plasma (PRP) contains various cytokines and growth factors which may be beneficial to the healing process of injured muscle. The aim of this study was to investigate the effect and molecular mechanism of PRP on migration of skeletal muscle cells. Skeletal muscle cells intrinsic to Sprague-Dawley rats were treated with PRP. The cell migration was evaluated by transwell filter migration assay and electric cell-substrate impedance sensing. The spreading of cells was evaluated microscopically. The formation of filamentous actin (F-actin) cytoskeleton was assessed by immunofluorescence staining. The protein expressions of paxillin and focal adhesion kinase (FAK) were assessed by Western blot analysis. Transfection of paxillin small-interfering RNA (siRNAs) to muscle cells was performed to validate the role of paxillin in PRP-mediated promotion of cell migration. Dose-dependently PRP promotes migration of and spreading and muscle cells. Protein expressions of paxillin and FAK were up-regulated dose-dependently. F-actin formation was also enhanced by PRP treatment. Furthermore, the knockdown of paxillin expression impaired the effect of PRP to promote cell migration. It was concluded that PRP promoting migration of muscle cells is associated with up-regulation of proteins expression of paxillin and FAK as well as increasing F-actin formation. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2506-2512, 2017.

Serum 25-hydroxyvitamin D cutoffs for functional bone measures in postmenopausal osteoporosis

This study sought to determine the minimal serum 25-hydroxyvitamin D [25(OH)D] concentration required to maintain bone health in postmenopausal women with low bone mass. A serum 25(OH)D concentration of 20 ng/mL rather than 30 ng/mL was appropriate for bone health.

INTRODUCTION

There is no consensus on the minimal serum 25-hydroxyvitamin D [25(OH)D] concentration required to maintain bone health. The aim of this study was to investigate the relationship between 25(OH)D measured via liquid chromatography-mass spectrometry (LC-MS/MS), which is the current gold standard, and biochemical markers of bone turnover, PTH, and bone mineral densitometry (BMD).

METHODS

The medical records of 750 postmenopausal women newly diagnosed with osteoporosis or osteopenia at Samsung Medical Center from 2009 to 2014 were investigated. Subjects were divided into four groups according to serum 25(OH)D concentration: <10, 10-20, 20-30, and ≥30 ng/mL. Serum concentrations of bone-specific alkaline phosphatase (BS-ALP), carboxy-terminal cross-linking telopeptide of type 1 collagen (CTx), intact PTH (iPTH), and BMD were compared among the four groups using analysis of covariance. Thresholds of 25(OH)D were then assessed using spline plots and locally weighted regression smoothing (LOESS) plots.

RESULTS

25(OH)D was negatively correlated with serum BS-ALP, CTx, and iPTH. Only femur neck and total femur BMD had significant positive relationships with 25(OH)D. Cutoff values of 11.9 and 9.7 ng/mL were estimated from the spline plots of femur neck and total femur BMD, respectively. For iPTH, the LOESS plot showed a steep decrease to a serum 25(OH)D concentration of about 20 ng/mL, followed by a plateau.

CONCLUSIONS

According to this study, a serum 25(OH)D concentration of 20 ng/mL, rather than 30 ng/mL, was appropriate for bone health.

Platelet rich plasma releasate promotes proliferation of skeletal muscle cells in association with upregulation of PCNA, cyclins and cyclin dependent kinases

Platelet rich plasma (PRP) contains various cytokines and growth factors which may be beneficial to the healing process of injured muscle. The purpose of this study is to investigate the effect and molecular mechanism of PRP releasate on proliferation of skeletal muscle cells. Skeletal muscle cells intrinsic to Sprague-Dawley rats were treated with PRP releasate. Cell proliferation was evaluated by 3-[4,5-Dimethylthiazol- 2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay and immunocytochemistry with Ki-67 stain. Flow cytometric analysis was used to evaluate the cell cycle progression. Western blot analysis was used to evaluate the protein expressions of PCNA, cyclin E1, cyclin A2, cyclin B1, cyclin dependent kinase (cdk)1 and cdk2. The results revealed that PRP releasate enhanced proliferation of skeletal muscle cells by shifting cells from G1 phase to S phase and G2/M phases. Ki-67 stain revealed the increase of proliferative capability after PRP releasate treatment. Protein expressions including cyclin A2, cyclin B1, cdk1, cdk2 and PCNA were up-regulated by PRP releasate in a dose-dependent manner. It was concluded that PRP releasate promoted proliferation of skeletal muscle cells in association with the up-regulated protein expressions of PCNA, cyclin A2, cyclin B1, cdk1 and cdk2.

Prevention of Simvastatin-Induced Inhibition of Tendon Cell Proliferation and Cell Cycle Progression by Geranylgeranyl Pyrophosphate

Statins have been reported to induce tendinopathy and even tendon rupture. The present study was designed to investigate the potential molecular mechanism underlying the adverse effect of simvastatin on tendon cells. An in vitro tendon healing model was performed using tendon cells isolated from rat Achilles tendons. The viability of tendon cells and cell cycle progression were examined by the MTT assay and flow cytometric analysis, respectively. Immunofluorescent staining for Ki-67 was used to assess the proliferation activity of tendon cells. Western blot analysis and coimmunoprecipitation was used to determine the protein expression of cell cycle-related proteins. To investigate the potential mechanism underlying the effect of statins on tendon cells, mevalonate, farnesyl pyrophosphate (FPP), or geranylgeranyl pyrophosphate (GGPP) was added to simvastatin-treated tendon cells. Simvastatin inhibited the in vitro tendon healing model and tendon cell proliferation in a dose-dependent manner. Immunofluorescent staining demonstrated reduced ki-67 expression in simvastatin-treated tendon cells. Furthermore, simvastatin induced cell cycle arrest at the G1 phase. The expression levels of cdk1, cdk2, cyclin A, and cyclin E were downregulated by simvastatin in a dose-dependent manner. The inhibitory effect of simvastatin was proved to mediate the reduction of mevalonate, and the addition of exogenous GGPP completely prevented the inhibitory effect of simvastatin on tendon cells. The present study demonstrated, for the first time, the molecular mechanism underlying simvastatin-induced tendinopathy or tendon rupture. GGPP was shown to prevent the adverse effect of simvastatin in tendon cells without interfering with its cholesterol-reducing efficacy.

Aging is associated with increased activities of matrix metalloproteinase-2 and -9 in tenocytes

Background

Most tendon pathology is associated with degeneration, which is thought to involve cyclic loading and cumulative age-related changes in tissue architecture. However, the association between aging and degeneration of the extracellular matrix (ECM) in tendons has not been investigated extensively.

Methods

We examined tenocytes from Achilles tendons taken from rats of three different ages (2, 12, and 24 months). Tenocyte viability was assessed using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Quantitative real-time polymerase chain reaction (PCR) was used to determine the levels of mRNAs that encode type-I collagen, matrix metalloproteinase (MMP)-2 and −9, tissue inhibitor of metalloproteinase (TIMP)-1 and −2 and transforming growth factor (TGF)-β1. Gelatin zymography was used to evaluate the enzymatic activities of MMP-2 and −9. Furthermore, the concentration of TGF-β1 in conditioned medium was evaluated using enzyme-linked immunosorbent assay (ELISA).

Results

The results of the MTT assay showed that the number of viable tenocytes decreased with age. No differences were observed in the levels of mRNAs that encode type-I collagen and TGF-β1 among the three age groups, and the TGF-β1 concentration did not change with age. However, mRNAs that encode MMP-2 and −9 were significantly more abundant in tenocytes from the aging group, and gelatin zymography revealed that the enzymatic activities of MMP-2 and −9 also increased significantly with age. Furthermore, as compared with young group, mRNAs that encode TIMP-1 and −2 were significantly decreased in tenocytes from the aging group.

Conclusions

Activities of MMP-2 and MMP-9 in tenocytes increase with age. This might provide a mechanistic explanation of how aging contributes to tendinopathy or tendon rupture with age.

The effects of aging on quantitative sonographic features of rotator cuff tendons

PURPOSE

Grayscale analysis is a practical, objective, and easy way to quantify echogenicity during ultrasonography. The purpose of the current study was to measure the changes in thickness and echogenicity that result from aging of the rotator cuff and long head of the biceps tendons.

METHODS

The study comprised 45 volunteers, aged between 20 and 84 years and without history of shoulder pain. Participants were divided into three groups: young, middle-aged, and old. All subjects underwent standard ultrasonography of both shoulders. Tendon thickness and tear were recorded, and images in both transverse and longitudinal scans were taken for grayscale analysis. To reduce the attenuation effect from skin and subcutaneous fat, we used the ratio of echogenicity of the tendon to that of the reference muscle and compared the tendon echogenicity among the different age groups. Sonographic findings were also correlated with age.

RESULTS

The supraspinatus tendon was significantly thicker in elderly participants and this was positively correlated with age. Moreover, the echogenicity ratio of the supraspinatus tendon decreased in the elderly group and showed a negative correlation with age. There was a higher prevalence of supraspinatus tendon tears in the older participants.

CONCLUSIONS

Our results indicate that supraspinatus tendons became thickened, hypoechogenic, and more likely to tear with age. The study presents a simple and useful method to investigate the echogenicity of the rotator cuff quantitatively.

Reproducibility of sonographic measurement of thickness and echogenicity of the plantar fascia

BACKGROUND

To evaluate the intra- and interrater reliability of ultrasonographic measurements of the thickness and echogenicity of the plantar fascia.

METHODS

Eleven patients (20 feet), who complained of inferior heel pain, and 26 volunteers (52 feet) were enrolled. Two sonographers independently imaged the plantar fascia in both longitudinal and transverse planes. Volunteers were assessed twice to evaluate intrarater reliability. Quantitative evaluation of the echogenicity of the plantar fascia was performed by measuring the mean gray level of the region of interest using Digital Imaging and Communications in Medicine viewer software.

RESULTS

Sonographic evaluation of the thickness of the plantar fascia showed high reliability. Sonographic evaluations of the presence or absence of hypoechoic change in the plantar fascia showed surprisingly low agreement. The reliability of gray-scale evaluations appears to be much better than subjective judgments in the evaluation of echogenicity. Transverse scanning did not show any advantage in sonographic evaluation of the plantar fascia.

CONCLUSIONS

The reliability of sonographic examination of the thickness of the plantar fascia is high. Mean gray-level analysis of quantitative sonography can be used for the evaluation of echogenicity, which could reduce discrepancies in the interpretation of echogenicity by different sonographers. Longitudinal instead of transverse scanning is recommended for imaging the plantar fascia.

Decreased proliferation of aging tenocytes is associated with down-regulation of cellular senescence-inhibited gene and up-regulation of p27

Symptomatic tendinopathy tends to be age-related. However, the molecular mechanisms of ageing and its effects on tenocyte proliferation and cell cycle progression are unknown. We examined tenocytes from Achilles tendons in rats from three age groups (young, 2 months; middle-aged, 12 months, and near senescence, 24 months). Tenocyte proliferation was assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry. Senescence-associated β-galactosidase (SA β-gal) staining was performed in all groups of tenocytes. mRNA and protein expression of cellular senescence-inhibited gene (CSIG) and p27 was measured by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot, respectively. The results of MTT assay revealed that tenocyte proliferation decreased with age (p < 0.05). Cell cycle progression was arrested at G0/G1 phase in senescent tenocytes. More senescent tenocytes expressed SA β-gal than young tenocytes did. By RT-PCR and Western blot analysis, the gene and protein expression of CSIG was found to be down-regulated, whereas that of p27 was up-regulated with age. In conclusion, the proliferation of tenocytes declines with age and is associated with the down-regulation of CSIG and up-regulation of p27.

Sonographic measurements of the thickness of the soft tissues of the interscapular region in a population of normal young adults

BACKGROUND

To use sonography (US) to measure the interscapular soft-tissue thickness and to determine any correlation with anthropometric indices.

METHODS

Fifty-five healthy young adults (21 men and 34 women) with a mean age of 22.1 ± 3.0 years (range, 18-35) were enrolled. High-resolution US was used to measure the bilateral soft-tissue thickness near the medial border of the scapula. Anthropometric indices, including body weight, height, and circumferences of chest, waist, and hip, were also measured.

RESULTS

On the right side, mean values ± standard deviation for the thickness of the trapezius, rhomboid, and posterior serratus muscles in millimeters were 4.9 ± 1.0, 6.3 ± 2.3, and 3.5 ± 1.4, respectively, for men and 3.4 ± 0.8, 3.8 ± 1.7, and 2.2 ± 1.5, respectively, for women. The thickness of each muscle was significantly greater in men than in women (p < 0.05). For both genders, no significant differences in the soft-tissue thicknesses were found between both sides. Based on the anthropometric indices, body weight was the only significant contributor to the soft-tissue thickness.

CONCLUSIONS

US is a practical tool for measuring soft-tissue thickness in the interscapular region. Body weight and soft-tissue thickness are closely associated.

Sonographic features of soft tissue tumors in the hand and forearm

BACKGROUND

High-resolution sonography is well suited for screening soft tissue masses because of its safety, low cost, and real-time, dynamic imaging. The purpose of our study was to elaborate the preoperative sonographic features of soft tissue tumors of the hand and forearm and the corresponding histologic results.

METHODS

Thirty-one soft tissue tumors of the hand and forearm were evaluated by ultrasound preoperatively. The mobility, consistency, echogenicity, margin, and color Doppler signal of each tumor were assessed. Dynamic study was also performed. The pathologic diagnosis was obtained after subsequent surgery.

RESULTS

The pathologic diagnoses of these soft tissue lesions were lipoma (n = 6), ganglion cyst (n = 6), neurilemmoma (n = 3), neurofibroma (n = 3), giant cell tumor (n = 10), tenosynovitis (n = 2), and malignant lymphoma (n = 1). An adjacent tendon or communication duct extending to the joint space could be found in most giant cell tumors and ganglion cysts; a traceable nerve could be found in most nerve sheath tumors. All benign tumors appeared well-defined. The only malignant tumor appeared ill-defined without a color Doppler signal.

CONCLUSION

Sonography enables a reliable diagnosis of the cystic or solid nature of soft-tissue lesions, accurate estimation of the volume, and precise three-dimensional localization of the abnormality. Examiners should perform a dynamic examination and trace the adjacent structure to obtain more diagnostic clues.

Comparison of the effects of swimming and Tai Chi Chuan on body fat composition in elderly people

BACKGROUND

Accumulation of fat and substantial loss of muscle mass are common phenomena in the elderly. In this study, we observed the effects of Tai Chi Chuan (TCC) and swimming, two exercises suitable for elderly people, on the percentage body fat and fat distribution by measuring subcutaneous adipose tissue thickness and body composition.

METHODS

Subjects were divided into three groups: regular swimmers (n = 20), regular TCC practitioners (n = 32), and age-matched control subjects (n = 31). Subcutaneous adipose tissue thickness was taken using a Lange skinfold caliper at the chests, abdomens, and thighs in the men, and the triceps, suprailium, and thighs in the women. Mid-arm circumference (MAC) was measured on the non-dominant upper arm using fiberglass tape. Body composition was analyzed using the Inbody 3.0 logo, a bioelectrical impedance analysis (BIA) system.

RESULTS

No significant differences were found between the three test groups in relation to total body adiposity and arm muscle circumference in the men and women. There was significantly less subcutaneous adipose tissue at the abdomen (p = 0.011) and thigh (p < 0.001) of TCC-group men and at the thighs (p < 0.001) of the swimming group compared with the control group. In women, only the thigh skinfold (p = 0.002) showed a decrease in the TCC group compared with the control group.

CONCLUSION

Swimming and TCC may not decrease total fat adiposity in elderly men and women, however, they may change body fat distribution due to certain muscle group usage. The differences observed in the effects of exercise on body fat distribution between elderly women and men may be gender-related.

Plantar fasciitis treated with local steroid injection: comparison between sonographic and palpation guidance

PURPOSE

To compare the effectiveness of sonographically guided and palpation-guided steroid injection for the treatment of proximal plantar fasciitis.

PATIENTS AND METHODS

Twenty-five consecutive patients with unilateral proximal plantar fasciitis were recruited and randomly divided into a sonographically guided group (n = 12) and palpation-guided group (n = 13). Proximal plantar fascia was assessed with a 5- to 12-MHz linear-array transducer. Pain intensity was quantified using a "tenderness threshold" (TT) and a visual analog scale (VAS). Injection of 7 mg (1 ml) of betamethasone and 0.5 ml of 1% lidocaine into the inflamed proximal plantar fascia was performed under the guidance of sonography or palpation. Patients were evaluated clinically and sonographically before injection and at 2 weeks, 2 months, and 1 year after injection. VAS- and TT-measured pain intensity, thickness, and echogenicity of the proximal plantar fascia, as well as the recurrence of heel pain, were assessed.

RESULTS

Both VAS- and TT-measured levels of pain improved significantly after steroid injection in both groups (p < 0.001). Also, the thickness decreased significantly after injection (p < 0.01 in the palpation-guided group; p < 0.001 in the sonographically guided group). The number of patients with hypoechogenicity at the proximal plantar fascia decreased after steroid injection in both groups (p < 0.01 for both groups). The recurrence rate of plantar fasciitis in patients of the palpation-guided group (6/13) was significantly higher than that of the sonographically guided group (1/12) (p < 0.05).

CONCLUSIONS

Steroid injection can be an effective way to treat plantar fasciitis, and injection under sonographic guidance is associated with lower recurrence of heel pain.

Improvement of Muscle Strength in Osteoarthritic Knee Patients After Intraarticular Knee Injection of Hyaluronan

OBJECTIVE

The objective of this study was to investigate whether the knee concentric and eccentric muscle strengths can be improved in patients with bilateral knee osteoarthritis after intraarticular hyaluronan injections.

DESIGN

A total of 25 patients with bilateral knee osteoarthritis and with a radiographic Ahlbäck grading scale of I or II participated in this study. One session of intraarticular knee injection of hyaluronan was given to both knees (weekly intraarticular knee hyaluronan injections for a total of 5 wks). Knee concentric and eccentric muscle strengths were recorded between 10 and 90 degrees of knee flexion. The recordings were done on two angular velocities, 80 and 240 degrees/sec. This study took place in a tertiary medical center with a gait laboratory and a KIN-COM isokinetic dynamometer.

RESULTS

An increase in concentric and eccentric muscle strength adjusted for body weight (P < 0.01) was observed in both knees, ranging between 5.1% and 27.7%.

CONCLUSION

The decreased knee muscle contraction strength (concentric and eccentric) can be improved in knee osteoarthritis patients with an Ahlbäck grading scale of I or II after five weekly intraarticular knee injections of hyaluronan.

Expression of phosphorylated histone H2AX in cultured cell lines following exposure to X-rays

PURPOSE

Exposure to ionizing radiation results in phosphorylation of histone H2AX (gammaH2AX) at sites of DNA double-strand breaks. To determine the relationship between gammaH2AX formation and radiosensitivity, the rate of formation and loss of gammaH2AX were examined in several cultured cell lines following exposure to 253 kV X-rays.

MATERIALS AND METHODS

Flow and image cytometry were both performed using a mouse monoclonal antibody against gammaH2AX. Immunoblotting was used to confirm cell line-dependent differences in antibody staining. Cell lines examined included V79 and CHO-K1 hamster cells, the human tumour cell lines SiHa, WiDr, DU145, WIL-2NS, HT144, HCC1937 and U87, and the normal cell strain HFL1. Radiosensitivity was measured using a standard clonogenic assay.

RESULTS

Using flow cytometry, gammaH2AX formation was detected 1 h after doses as low as 20 cGy. Peak levels of gammaH2AX were observed within 15-30 min after irradiation and both the rate of radiation-induced gammaH2AX formation and loss were cell type dependent. Maximum levels of gammaH2AX formation were lower for HT144 cells mutant for the ataxia telangiectasia gene. Half-times of loss after irradiation ranged from 1.6 to 7.2 h and were associated with a decrease in the total number of foci per cell. The half-time of loss of gammaH2AX was correlated with clonogenic survival for 10 cell lines (r2=0.66).

CONCLUSIONS

GammaH2AX can be detected with excellent sensitivity using both flow and image analysis. The rate of gammaH2AX loss may be an important factor in the response of cells to ionizing radiation, with more rapid loss and less retention associated with more radioresistant cell lines.

Pore-to-pore hopping model for the interpretation of the pulsed gradient spin echo attenuation of water diffusion in cell suspension systems

A simplified pore-to-pore hopping model for the two-phase diffusion problem is developed for the analysis of the pulsed gradient spin echo (PGSE) attenuation of water diffusion in the condensed cell suspension systems. In this model, the two phases inside and outside the cells are treated as two different kinds of pores, and the spin-bearing molecules perform hopping diffusion between them. The size and the orientations of those two respective pores are considered, and then the diffraction pattern of the PGSE attenuation may be well simulated. Nevertheless, the intensity of the characteristic peak decreases with increasing membrane permeability, from which the exchange time may be estimated. We then analyze the experimental 1H PGSE results of the erythrocytes suspension system. The water-residence lifetime in the erythrocyte is obtained to be 10 ms, which is the same as that estimated from the two-region approximation. Furthermore, the PGSE attenuation curve of addition of p-Chloromercuribenzenesulfonate (p-CMBS) is also discussed. It predicts that the alignment of erythrocytes will become normal to the magnetic field direction after the addition of p-CMBS, and inspection using a light microscope confirms that result.

Optimized combinations of abatement strategies for urban mobile sources

The maximum incremental reactivity (MIR) scale was chosen as a practical index for quantifying ozone-forming impacts. The integer linear and nonlinear programming techniques were employed as the optimization method to maximize MIR and volatile organic compound (VOC) reductions, and minimize ozone's marginal cost with varied control costs. Mobile vehicles were divided into nine categories according to the demands of decision makers and the distinctive features of local circumstance in metro-Taipei. The emission factor (EF) and vehicle kilometers traveled (VKT) of each kind of vehicle were estimated by MOBILE5B model via native parameters and questionnaires. Compressed natural gas (CNG) and inspection and maintenance (I/M) were the alternative control programs for buses and touring buses; liquefied petroleum gas (LPG), I/M, methanol, electrical vehicle (EV) were for taxis and low duty gasoline vehicles. EV, methanol, and I/M were the possible control methods for two-stroke and four-stroke engine motorcycles; I/M programs for low-duty diesel trucks, heavy-duty diesel trucks, and low-duty gasoline trucks. The results include the emission ratios of specific vehicle to all vehicles, the best combination of abated measures based on different objectives, and the marginal cost for ozone and VOC with varied control costs.