Treatment of Ribbing disease with 5-year follow-up and literature review.

Ribbing disease, or multiple diaphyseal sclerosis, is a rare diaphyseal sclerosis of unknown etiology. Patients with this pathology usually present with asymmetric pain limited to the lower extremities. Though all efforts are made to relieve the progressive pain associated with Ribbing disease, no medical or surgical treatments have been established yet. In this case report, we followed up a Ribbing case with sclerotic bone fenestration for 5 years. The radiological changes and the clinical effects are described, and the different Ribbing treatments are then briefly reviewed.

Nonunion of osteoporotic vertebral compression fracture with a severe spinal stenosis treated in minimally invasive manner: a case report.

Compared with numerous encouraging reports of percutaneous kyphoplasty (PKP) in treatment of painful osteoporotic vertebral compression fractures, there have been fewer reports on the role of PKP in the treatment of nonunion of osteoporotic vertebral compression fractures. Even less is known about the use of PKP in treating nonunion of osteoporotic vertebral compression fractures with severe spinal stenosis. We reported an 87-year-old man presented with half a year back pain and numbness of both legs after back sprain 6 months ago. Nonunion of L3 with severe spinal stenosis was recognized in the preoperative films. Bone mineral analysis showed severe osteoporosis with a T-score of -4.7. He refused to receive the decompression surgery. As a result, PKP was introduced to him as an alternative option. The patient experienced complete pain relief after PKP without any complication. Meanwhile, it was an interesting finding that numbness of both legs disappeared. After 12 months follow-up, the patient was asymptomatic. This case illustrated that PKP could be considered as one of the options for nonunion of osteoporotic vertebral compression fractures with severe spinal stenosis.

Associations of ATGL gene polymorphisms with chicken growth and fat traits.

Adipose triglyceride lipase (ATGL) catalyses the initial step in triglyceride hydrolysis, so the ATGL gene is a candidate for growth and fat traits in chickens. Nine reported single-nucleotide polymorphisms (SNPs) located in 3 exons of the chicken ATGL gene were chosen for genotyping an F2 population. Only 5 SNPs were confirmed for polymorphisms and used for association analyses. The results show that c.531G>A (p.E177Syn) was not associated with any growth and fat traits (P > 0.05), but c.782G>A (p.S261N) was associated with body weight (BW) on days 14, 21, 35, 63, 70, 77, cingulated fat width and abdominal fat pad weight (P < 0.05), and significantly associated with BW on days 42, 49, and 56 (P < 0.01). Significant associations of c.903C>T (p.F301Syn) with BW on days 49 and 77 days and crude protein content of breast muscle (P < 0.05), and c.1164G>A (p.K388Syn) with BW on day 7 (P < 0.05) were also detected. Additionally, c.1069T>C (p.L357Syn) was associated with breast muscle colour (P < 0.05), and significantly associated with crude fat (ether extract) content of breast muscle (P < 0.01). Thus the missense SNP of c.782G>A (p.S261N) was significantly associated with the largest number of chicken growth and fat traits in this study.

Observation of the ultrastructure of anterior cruciate ligament graft by atomic force microscopy.

This study presented the fibril ultrastructure of retrieved grafts from the reconstruction of anterior cruciate ligament (ACL) using atomic force microscopy (AFM). The tapping mode images of the AFM were taken from different areas of the longitudinally cut grafts. Regular arrangement of collagen fibrils was found in certain areas of the graft. In many areas, however, the fibrils were not well arranged in a single direction, with some smaller fibrils oriented vertically to larger parallel fibrils. The crossing and tangling of fibrils in ACL grafts was well represented in the three-dimensional AFM image. This abnormality of graft ultrastructure might indicate the possible alteration of the mechanical environment after ACL reconstruction. This study demonstrated the suitability and importance of ultrastructure observation of ACL grafts by AFM.

Effects of LncRNA KCNQ1OT1 on proliferation and migration of ovarian cancer cells by Wnt/ß-catenin.

OBJECTIVE: To explore the role of long noncoding ribonucleic acid (lncRNA) KCNQ1OT1 in the proliferation, apoptosis, and migration of ovarian cancer cells via Wnt/ß-catenin. MATERIALS AND METHODS: Ovarian cancer A2780 cells were divided into three groups, namely control group, KCNQ1OT1 overexpression group, and KCNQ1OT1 knockdown group. Next, the effect of KCNQ1OT1 on the proliferation of ovarian cancer A2780 cells was detected by cell counting kit-8 (CCK-8) assay. Wound healing assay and transwell assay were carried out to determine the influence of KCNQ1OT1 on the migration ability of ovarian cancer A2780 cells. The role of KCNQ1OT1 in the cell cycle of ovarian cancer A2780 cells was detected via flow cytometry. The impact of KCNQ1OT1 on the expression level of ß-catenin protein in ovarian cancer A2780 cells was determined through Western blotting and fluorescence immunoassay. RESULTS: The proliferation rate of cells was overtly decreased in KCNQ1OT1 knockdown group but significantly increased in KCNQ1OT1 overexpression group. The results of both wound healing and transwell assays showed that the migration ability of cells was reduced in KCNQ1OT1 knockdown group but raised in KCNQ1OT1 overexpression group. According to flow cytometry, the cell cycle was clearly arrested in the G0/G1 phase in KCNQ1OT1 knockdown group. The results of Western blotting and fluorescence immunoassay revealed that compared with that in control group, the expression level of ß-catenin protein evidently declined in KCNQ1OT1 knockdown group, but it was notably elevated in KCNQ1OT1 overexpression group. CONCLUSIONS: Increased lncRNA KCNQ1OT1 in ovarian cancer cells promotes the expression of ß-catenin, thereby facilitating the proliferation and migration of ovarian cancer cells.

MicroRNA-384 downregulates SETD8 expression to suppress cell growth and metastasis in osteosarcoma cells.

OBJECTIVE: MiR-384 was reported to be downregulated and functioned as a tumor suppressor in several cancers. However, the expression and function of miR-384 in osteosarcoma (OS) have not been investigated. In the present study, we aimed to analyze the effect and mechanism of miR-384 in the progression of OS. PATIENTS AND METHODS: Quantitative Real-time polymerase chain reaction (qRT-PCR) was used to determine the expression of miR-384 in OS tissues and cells. MTT assay, colony formation analysis, Transwell assays were performed to analyze the role of miR-384 in human OS cells. Western blotting was applied to analyze the expression of SETD8, and the luciferase reporter assay was used to assess the target gene of miR-384 in OS cells. RESULTS: We found that miR-384 was significantly lowly expressed in OS tissues and OS cell lines compared with the adjacent noncancerous tissues and normal bone cell lines, respectively. Further functional analysis indicated that up-regulation of miR-384 significantly inhibited OS cells proliferation, migration, and invasion, but down-regulation of miR-384 had the opposite effects on OS cells in vitro. Moreover, SETD8 was identified as the potential target of miR-384 using dual luciferase assay, qRT-PCR and Western blot. Finally, we observed that upregulation of SETD8 reversed the effects of overexpressing of miR-384 on the proliferation, migration, and invasion of OS. CONCLUSIONS: Our data provided the first evidence which supported the function of miR-384 as a tumor suppressor in OS by targeting SETD8.

Non-inductive vertical position measurements by Faraday-effect polarimetry on EAST tokamak.

Vertical instability control in an elongated plasma is highly desirable for a tokamak reactor. A multi-channel 694 GHz far-infrared laser-based polarimeter-interferometer system has been used to provide a non-inductive vertical position measurement in the long-pulse EAST tokamak. A detailed comparison of vertical position measurements by polarimetry and external inductive flux loops has been used to validate Faraday-effect polarimetry as an accurate high-time response vertical position sensor.

Clinical significance of long non-coding RNA EWSAT1 as a novel prognostic biomarker in osteosarcoma.

OBJECTIVE: Long non-coding RNA EWSAT1 (EWSAT1) has been identified as a tumor promoter in several tumors, but its prognostic values in osteosarcoma have not been reported. The purpose of this study was to explore the association between EWSAT1 expression and prognosis of osteosarcoma patients. PATIENTS AND METHODS: EWSAT1 levels were examined in 176 osteosarcoma tissues and matched normal bone tissues by qRT-PCR analysis. The associations of EWSAT1 expression with clinicopathologic variables were analyzed. The survival curves were calculated by the Kaplan-Meier method. The Cox proportional hazards regression model was used to identify independent prognostic factors with independent prognostic for overall survival (OS) and disease-free survival (DFS). RESULTS: We found that EWSAT1 levels were significantly higher in osteosarcoma tissues compared with matched non-cancerous tissues (p<0.01). The level of EWSAT1 expression was significantly associated with clinical stage (p=0.001) and distant metastasis (p=0.011). Then, Kaplan-Meier analysis showed that high EWSAT1 expression level was associated with poorer OS (p=0.0007) and DFS (p=0.0010). Furthermore, Cox multivariate analyses demonstrated that EWSAT1 expression was an independent prognostic factor for both OS (p<0.001) and DFS (p=0.001) in osteosarcoma patients CONCLUSIONS: Increased EWSAT1 expression was associated with poor outcomes in osteosarcoma patients, and EWSAT1 could serve as a potential unfavorable prognostic biomarker.

3D passive stabilization of n = 0 MHD modes in EAST tokamak.

Evidence is shown of the capability of non-axisymmetrical conducting structures in the Experimental Advanced Superconducting Tokamak (EAST) to guarantee the passive stabilization of the n = 0 MHD unstable mode. Suitable numerical modeling of the experiments allows a clear interpretation of the phenomenon. This demonstration and the availability of computational tools able to describe the effect of 3D conductors will have a huge impact on the design of future fusion devices, in which the conducting structures closest to plasma will be highly segmented.

The origins of the thenar and hypothenar muscles.

This paper presents an anatomical study of the origins of the thenar and hypothenar muscles and postulates the causes of weakness and pillar pain following carpal tunnel release.

Behavioral evidence for the role of noradrenaline in putative anxiolytic and sedative effects of benzodiazepines.

The effects of clonidine on the antianxiety and sedation of benzodiazepines (BZD) were assessed respectively in rats trained in a two-lever diazepam cue discrimination procedure and in single-lever fixed-ratio (FR) water-reinforced performance. Clonidine (10-60 micrograms/kg) significantly shifted to the left the dose-effect curves of diazepam in the discrimination paradigm. This treatment also shifted generalization dose-effect curves of the diazepam cue to chlordiazepoxide and CL 218,872 to the left in the drug discrimination procedure. The diazepam cue was antagonized in a dose-related manner by Ro 15-1788, but not by bicuculline. Clonidine also potentiated the rate-decreasing effects of diazepam on the FR schedule when the dose of diazepam was increased to 0.3 mg/kg, but not the milder rate-decreasing effect of CL 218,872 until the dose of CL 218,872 was increased to 10 mg/kg. The potentiating effects of clonidine on the stimulus control and depression of diazepam were antagonized by yohimbine. Yohimbine (1.0 mg/kg) also significantly shifted the dose-effect curve of diazepam cue to the right. Bicuculline (3 mg/kg) completely antagonized the rate-decreasing effect of diazepam (1 mg/kg), but significantly potentiated the rate-suppressant effect of clonidine (10 micrograms/kg). These results suggest that the central noradrenaline (NA) system may be involved not only in the antianxiety, but also the sadative action of BZD. The nature of NA involvement in relation to the different subtypes of BZD receptors requires further exploration.

Effect of pregnancy on joint contracture in the rat knee.

As there is evidence that ligamentous laxity is affected by the female hormones, we hypothesized that hormonal changes occurring during pregnancy could have a therapeutic role in preventing the development of a joint contracture. Knee joint contractures were created in pregnant and nonpregnant rats. After 2 wk of immobilization, the degree of contracture was measured with structural properties of the medial collateral and anterior cruciate ligaments and the pubic symphysis. Although not statistically significant, there was a general trend toward reduced contracture in pregnant compared with nonpregnant rats. Cutting the posterior capsule significantly decreased contracture for both the pregnant and nonpregnant groups, confirming the contribution of capsular structures to contracture. Ultimate loads of the medial collateral and anterior cruciate ligaments significantly decreased after immobilization compared with control, but there was no significant effect due to pregnancy. Stiffness and ultimate load of the pubic symphysis were not significantly different between pregnant and nonpregnant groups. The trend toward reduced contracture with pregnancy points toward a possible therapeutic role for female hormones in the prevention of postoperative and/or posttraumatic joint contracture.

Tendon-Defect and muscle-unloaded models for relating a rotator cuff tear to glenohumeral stability.

Rotator cuff tear and glenohumeral instability are closely related. Any tear may disturb muscle force generation due to pain inhibition. In addition, a full-thickness tear may foster instability by removing a structural element constraining the joint. It was hypothesized that the loss of both dynamic force and static constraint with a rotator cuff tear will affect glenohumeral stability. In a tendon-defect model, dynamic and static elements of the joint were sacrificed. In a muscle-unloaded model, only the dynamic element was removed. The location and size of the defect were also investigated. The effect on instability of a small tendon defect was less than that of muscle unloading, implying that a patient with a small tear would have less instability than a patient with weak or nonfunctioning supraspinatus and infraspinatus muscles. On the other hand, with a larger tear the defect had a greater effect than muscle-unloading because sectioning of the glenohumeral and coracohumeral ligaments was included in the model. Clinically, such a defect in the front is critical for anterior stability because it might insult the important anterior capsule ligamentous complex. Orthopaedic surgeons should pay attention, therefore, to the effect of possible associated lesions of static constraints based on the size and location of the tear in addition to the dynamic stabilizer.

Reaction of a human head/neck/torso system to shock.

The purpose of this study is to predict human response to, and potential damage from, impact loading by using numerical and physical models to monitor the head and thoracic reactions, intervertebral disk pressures, muscle elongations, and some internal organ pressures. The numerical model consists of a three-dimensional lumped-parameter system of ten rigid bodies connected by nine intervertebral joints and 28 muscle pairs. The masses represent the head; cervical vertebrae C1-C2, C3-C4, C5-C6, C7-T1 (the first thoracic vertebra); the entire thorax; lumbar vertebrae L1-L2, L3, L4-L5; and the pelvis. The physical model consists of: a water-filled cadaver skull, held in position by attached ligaments; plastic skeletal components involving vertebrae, sternum, ribs and pelvis; silicon rubber intervertebral disks; fabric muscles and ligaments; and water-filled containers replicating the liver, spleen and kidneys. The pelvis of the model is affixed to a plate mounted on a sled that runs on a track. Loading is applied by deceleration from a given velocity that occurs due to the impact of the sled with a fixed aluminum block. Results from the numerical model are compared with corresponding experimental information from the physical structure. Good correlation was obtained in these comparisons up to about 200-250 ms after impact. The results indicate that the head, cervical muscles and disks in the lumbar region are subjected to the greatest force changes and thus are most likely to be injured.

Development and validation of a nanometer manipulation and measurement system for biomechanical testing of single macro-molecules.

A biomechanical testing system for single macro-molecules has been developed using optical tweezers. To achieve nanometer manipulation and measurement, a piezo-stage and an interferometer were adopted. A systematic calibration was then performed on the displacement resolution. The piezo-stage has a noise level around 1 nm standard deviation, and the interferometer has a noise level of less than 5 nm standard deviation. The results revealed that the system has a nanometer resolution which is sufficient for the measurement of deformation and stiffness of single macro-molecules.

Determination of spinal facet joint loads from extra articular strains--a theoretical validation.

Loads on the facet joints of the lumbar spine may play a role in low back pain. Abnormal loading of the facets, either primarily or as a consequence of disc degeneration, may accelerate their degeneration. Study of these phenomena is difficult, since here are few methods for a direct measure of facet forces occurring in vivo. The authors developed a method for the direct measure of facet forces in a canine animal model of spine disease using strain gages. The method used empirical calibration of the strain gages, which was used to reduce experimental strain output to facet force during function. In this Technical Note, a theoretical model is formulated, solved and validated which gives a theoretical basis for the data reduction method. The facet is modeled as a cantilevered plate and deformations, as function of applied normal load, solved for using a finite difference method. The model is validated by comparison with two experiments with strain-gaged facets. Results from the model show that a minimum of three strain gages is required to determine uniquely the location and magnitude of an applied load to the facet, and that at least two gages should be placed in the region where the cranial articular process joins the pedicle with the gage axis parallel to that of the process. Plate surface strains were found to be insensitive to changes in the area of the applied loads, for a given resultant force magnitude. The method may be useful in other applications in which resultant force magnitude and location need to be measured on plate-like structures.

Determination of the proximity tolerance for measurement of surface contact areas using a magnetic tracking device.

Undisrupted joint contact areas can be determined based on surface proximity from combined surface geometry and bony kinematics measured with a magnetic tracking device. This technique is useful for evaluating the apparent region of contact in the normal joint. After disruption of the supporting structures or other simulated pathology, the locations and size of the contact region can be compared with the normal condition. However, the contact results may be highly sensitive to measurement errors. In this study, the accuracy of this method was evaluated for three simple geometric objects: (1) a flat plate, (2) a cylinder, and (3) a sphere, all in contact with a flat surface. The results indicated the contact can be determined within an average proximity of 0.16 +/- 0.01 mm (mean +/- standard error) with the flat plate, 0.07 +/- 0.02 mm with the cylinder, and 0.06 +/- 0.08 mm with the sphere. The proximity values are nearly the same as the translational accuracy of the equipment, and might be used as thresholds for in vitro studies.

A theoretical model of the knee and ACL: theory and experimental verification.

A three-dimensional mathematical model of the human knee joint was developed to examine the role of single ligaments, such as an anterior cruciate ligament (ACL) graft in ACL reconstruction, on joint motion and tissue forces. The model is linear and valid for small motions about an equilibrium position. The knee joint is modeled as two rigid bodies (the femur and the tibia) interconnected by deformable structures, including the ACL or ACL graft, the cartilage layer, and the remainder of the knee tissues (modeled as a single element). The model was demonstrated for the equilibrium condition of the knee in extension with an anterior tibial force, causing anterior drawer and hyperextension. The knee stiffness matrix for this condition was measured for a human right knee in vitro. Predicted model response was compared with experimental observations. Qualitative agreement was found between model and experiment, validating the model and its assumptions. The model was then used to predict the change in graft and cartilage forces and joint motion of the knee due to an increment of load in the normal joint both after ACL removal and with various altered states simulating ACL reconstructions. Results illustrate the interdependence between loads in the ACL graft, other knee structures, and contact force. Stiffer grafts and smaller maximum unloaded length of the ligament lead to higher graft and contact forces. Changes in cartilage stiffness alter load sharing between ACL graft and other joint tissues.