Locking versus nonlocking superior plate fixations for displaced midshaft clavicle fractures: A prospective randomized trial comparing clinical and radiografic results.

BACKGROUND: It is unknown whether locking or nonlocking superior plate fixation is better for managing displaced midshaft clavicle fractures. Therefore, we aimed to compare the clinical and radiographic outcomes of locking and nonlocking superior plate fixation of displaced midshaft clavicle fractures. METHODS: A total of 102 consecutive patients with displaced midshaft clavicle fractures (2B1 and 2B2 in Robinson classification) participated in this randomized controlled trial; 12 patients were excluded. Surgeries were performed using a 3.5-mm Locking Compression Plate (LCP) between 2007 and 2015. Patients were treated either with a locking plate (group L, n = 45) or a nonlocking plate (group N, n = 45). In both groups, the plates were fixed to the proximal and distal clavicle with two and/or three screws, respectively. The main outcome measures were complication rates, time to bone union, and Constant score. RESULTS: Forty-two patients in group L (mean age, 45.9 years) and 41 in group N (mean age, 43.6 years) were followed. The overall complication rates in groups L and N were 7.2% (three peri-implant fractures) and 7.3% (non-union, deformed plate, and peri-implant fracture), respectively (p = .98). The average time to union significantly differed between groups (L vs. N: 13.0 ± 4.1 vs. 17.5 ± 6.3 weeks; p < .01). However, the Constant score at the final follow-up was not significantly different between groups (L vs. N: 87.0 ± 12.3 vs. 89.8 ± 9.1). CONCLUSIONS: Similar complication rates and clinical results were found for locking and nonlocking superior plate fixation for displaced midshaft clavicle fractures. However, the time to bone union was shorter with the locking plate. This study suggests that both plating systems are effective for treating displaced midshaft clavicle fractures. LEVEL OF EVIDENCE: Therapeutic, level I.

Open Bankart repair plus inferior capsular shift versus arthroscopic Bankart repair without augmentations for traumatic anterior shoulder instability: A prospective study.

PURPOSE: Arthroscopic treatment of shoulder instability has some advantages (including short surgical time, less morbidity, less postoperative pain, reduced hospitalization time, and decreased risk of complications) compared with open procedures. We performed a prospective study comparing open repair with arthroscopic repair for recurrent anterior shoulder instability. The aim was to clarify the relative effectiveness of open Bankart repair plus inferior capsular shift (OBRICS) and arthroscopic Bankart (AB) repair without augmentations with approximately 5 years of follow-up. METHODS: We investigated 32 shoulders of 30 patients (24 men and 6 women) undergoing OBRICS (15 shoulders of 17 patients; two patients were bilateral) and AB (15 shoulders of 15 patients). The average follow-up was 5 years and 2.5 months (range: 60-66 months). The clinical evaluation included recurrent instability rate, range of motion, and postoperative rehabilitation. All patients were assessed using the scoring systems of Rowe and the University of California at Los Angeles (UCLA) preoperatively and during the final evaluation. RESULTS: Recurrent instability rates were significantly different between the OBRICS (0%) and AB (26.6%) groups ( p = 0.022). There were fewer limitations of external rotation (ER), ER at 90° abduction, and horizontal extension for AB than for OBRICS postoperatively ( p < 0.05). The mean Rowe and UCLA scores for both methods were not significantly different at final follow-up. CONCLUSION: Our data suggest that OBRICS leads to a lower rate of recurrent instability. However, those with AB had fewer ER and horizontal extension limitations.

The cancer stem cell marker CD133 interacts with plakoglobin and controls desmoglein-2 protein levels.

The pentaspan membrane glycoprotein CD133 (also known as prominin-1) has been widely used as a marker for both cancer and normal stem cells. However, the function of CD133 has not been elucidated. Here we describe a cancer stem cell line established from clear cell carcinoma of the ovary (CCC) and show that CD133 interacts with plakoglobin (also known as γ-catenin), a desmosomal linker protein. We further demonstrate that knockdown of CD133 by RNA interference (RNAi) results in the downregulation of desmoglein-2, a desmosomal cadherin, and abrogates cell-cell adhesion and tumorigenicity of CCC stem cells. We speculate that CD133 may be a promising target for cancer chemotherapy.

Clinical results of a surgical technique using endobuttons for complete tendon tear of pectoralis major muscle: report of five cases.

BACKGROUND: We herein describe a surgical technique for the repair of complete tear of the pectoralis major (PM) tendon using endobuttons to strengthen initial fixation. METHODS: Five male patients (3 judo players, 1 martial arts player, and 1 body builder) were treated within 2 weeks of sustaining complete tear of the PM tendon. Average age at surgery and follow-up period were 28.4 years (range, 23-33) and 28.8 months (range, 24-36). A rectangular bone trough (about 1 × 4 cm) was created on the humerus at the insertion of the distal PM tendon. The tendon stump was introduced into this trough, and fixed to the reverse side of the humeral cortex using endobuttons and non-absorbable suture. Clinical assessment of re-tear was examined by MRI. Shoulder range of motion (ROM), outcome of treatment, and isometric power were measured at final follow-up. RESULTS: There were no clinical re-tears, and MRI findings also showed continuity of the PM tendon in all cases at final follow-up. Average ROM did not differ significantly between the affected and unaffected shoulders. The clinical outcomes at final follow-up were excellent (4/5 cases) or good (1/5). In addition, postoperative isometric power in horizontal flexion of the affected shoulder showed complete recovery when compared with the unaffected side. CONCLUSIONS: Satisfactory outcomes could be obtained when surgery using the endobutton technique was performed within 2 weeks after complete tear of the PM tendon. Therefore, our new technique appears promising as a useful method to treat complete tear of the PM tendon.

Establishment of an immortalized human extravillous trophoblast cell line by retroviral infection of E6/E7/hTERT and its transcriptional profile during hypoxia and reoxygenation.

Investigation into the function of human trophoblasts has been largely restricted by a lack of suitable cell models. We aimed to produce normal human trophoblast cell lines with a long lifespan and to provide an ideal in vitro cell model. Primary human trophoblast cells were derived from a placenta that had undergone elective abortion at the 7th week of gestation. The cells were immortalized by infection with retroviral expression vectors containing the type 16 human papillomaviruses E6 and E7 in combination with human telomerase reverse transcriptase (hTERT). Characterization of the cell line was performed by immunocytochemistry using a panel of antibodies, Western blotting, real-time RT-PCR, an invasion assay, gelatin zymography, karyotype analysis and a nude mouse assay. Gene expression profiles under hypoxia (1% O2, 1 h) and subsequent reoxygenation (20% O2, 6 h) were analyzed using cDNA microarray. Immunocytochemistry revealed an extravillous trophoblastic phenotype by positive staining for hCGbeta, cytokeratin 7, HLA-G and CD9. A transwell insert invasion assay showed the invasiveness of this cell line and gelatin zymography detected the secretion of MMP-2 and MMP-9. Karyotype analysis exhibited an almost normal chromosomal number which ranged from 46 to 48 and the cells showed no tumorigenecity in a nude mouse assay. Forty-three genes showing reversible up- or down-regulation during hypoxia were detected using an oligonucleotide array. This newly immortalized cell line, HChEpC1b, is a useful model for the study of extravillous trophoblast function.

The association of deamidation of Bcl-xL and translocation of Bax to the mitochondria through activation of JNK in the induction of apoptosis by treatment with GSH-conjugated DXR.

We investigated the induction of apoptosis via deamidation of Bcl-xL and translocation of Bax to the mitochondria by treatment with GSH-DXR. GSH-DXR treatment of HepG2 cells, which did not express GST P1-1, exhibited deamidation of Bcl-xL, and the degree of deamidation was related to the activation of caspase-3. Overexpression of GST P1-1 in HepG2 cells decreased both the Bcl-xL deamidation and caspase-3 activation induced by treatment with GSH-DXR. Bcl-xL deamidation and caspase-3 activation were also suppressed by co-treatment with SP600125, a specific inhibitor of JNK activity. Overexpression of wild-type Bcl-xL in HepG2 decreased GSH-DXR-induced apoptosis although deamidation was observed. However, expression of the deamidated mutant of Bcl-xL, in which aspartic acid was substituted for both arginine 52 and 66 (N52,66D-Bcl-xL), exhibited high sensitivity for the induction of apoptosis. Expression of the Bcl-xL mutant, in which alanine was substituted for both arginine 52 and 66 (N52,66A-Bcl-xL), suppressed deamidation and showed resistance to the induction of apoptosis by treatment with GSH-DXR. On the other hand, endogenous Bax and overexpressed Flag-Bax were localized in the cytosolic fraction of HepG2 cells. Treatment of the cells with GSH-DXR caused translocation of Flag-Bax to the mitochondrial fraction following the induction of apoptosis. The induced apoptosis was enhanced by the expression of Flag-Bax. Moreover, Flag-Bax was partly located in the mitochondrial fraction in N52,66D-Bcl-xL-expressed cells without the induction of apoptosis. Therefore, the induction of apoptosis by treatment of HepG2 with GSH-DXR was enhanced, thereby facilitating the release of cytochrome c by both deamidated inactivation of Bcl-xL and functional translocation of Bax to the mitochondria via JNK activation. Deamidation of Bcl-xL might be induced in order to translocate Bax to the mitochondria.

Low-intensity pulsed ultrasound stimulation enhances TIMP-1 in nucleus pulposus cells and MCP-1 in macrophages in the rat.

Recent studies have reported that low-intensity pulsed ultrasound (LIPUS) stimulates cell proliferation and proteoglycan production in rabbit intervertebral disc cells, and moreover promotes the secretion of MCP-1 (monocyte chemotaxis protein-1) from macrophages in a disc organ culture model. These findings suggest the possible application of LIPUS for biological repair of disc degeneration and herniation. Although the mechanisms involved are not well understood, several cytokine pathways may play a role. Therefore, in order to evaluate the effect of LIPUS stimulation on cytokine production by nucleus pulposus cells and macrophages, in vitro culture studies were designed. Nucleus pulposus cells and macrophages were collected from Sprague-Dawley rats, cultured separately in a monolayer, and stimulated with LIPUS for 7 days. After culture, the culture medium and the cells were analyzed by cytokine array, RT-PCR, and ELISA. Cytokine array showed that LIPUS stimulation significantly upregulated TIMP-1 (tissue inhibitor of metalloproteinase-1) in the nucleus pulposus and MCP-1 in macrophages in comparison with the control. This was confirmed at the gene level by RT-PCR in nucleus pulposus cells and macrophages after stimulation with LIPUS. Quantitative evaluation of these proteins by ELISA showed higher levels in nucleus pulposus cells and macrophages stimulated by LIPUS than in controls. These results showed that LIPUS stimulation significantly activated TIMP-1 and MCP-1 in nucleus pulposus cells and macrophages at both the protein and gene levels, suggesting that LIPUS may be a promising supplemental treatment for intervertebral disc herniation.

Transplantation of mesenchymal stem cells in a canine disc degeneration model.

Transplantation of mesenchymal stem cells (MSCs) is effective in decelerating disc degeneration in small animals; much remains unknown about this new therapy in larger animals or humans. Fas-ligand (FasL), which is only found in tissues with isolated immune privilege, is expressed in IVDs, particularly in the nucleus pulposus (NP). Maintaining the FasL level is important for IVD function. This study evaluated whether MSC transplantation has an effect on the suppression of disc degeneration and preservation of immune privilege in a canine model of disc degeneration. Mature beagles were separated into a normal control group (NC), a MSC group, and the disc degeneration (nucleotomy-only) group. In the MSC group, 4 weeks after nucleotomy, MSCs were transplanted into the degeneration-induced discs. The animals were followed for 12 weeks after the initial operation. Subsequently, radiological, histological, biochemical, immunohistochemical, and RT-PCR analyses were performed. MSC transplantation effectively led to the regeneration of degenerated discs. FACS and RT-PCR analyses of MSCs before transplantation demonstrated that the MSCs expressed FasL at the genetic level, not at the protein level. GFP-positive MSCs detected in the NP region 8 weeks after transplantation expressed FasL protein. The results of this study suggest that MSC transplantation may contribute to the maintenance of IVD immune privilege by the differentiation of transplanted MSCs into cells expressing FasL.

Synergistic effect of low-intensity pulsed ultrasound on growth factor stimulation of nucleus pulposus cells.

Low-intensity pulsed ultrasound (LIPUS) has been reported to stimulate the activity of various cells. We have reported that the capacity of human intervertebral nucleus pulposus cell line to synthesize proteoglycan (PG) was increased by exposure to LIPUS, and postulated that one of the mechanisms underlying this response was an increase in expression of the transforming growth factor-beta type I receptor gene (TGFbetaR1). Therefore, the present study was conducted to assess the synergistic effect of LIPUS and TGF-beta on nucleus pulposus cells harvested from canines. The cells were cultured under four different sets of conditions: control group (Group A), LIPUS group (Group B), TGF-beta1 group (Group C), and LIPUS + TGF-beta1 group (Group D). They were evaluated by measuring cell proliferation, PG synthesis, PG content, gene expression of TGFbetaR1, and TGF-beta1 concentration. There were no significant differences in proliferation during culture. However, PG synthesis and endogenous TGF-beta1 production increased and demonstrated a synergistic effect between LIPUS and TGF-beta. Because LIPUS is safe and noninvasive, the results of the present study suggest that it would be a promising new therapy for prevention of intervertebral disc degeneration, which is said to be one of the primary causes of low back pain.

Regenerative effects of transplanting mesenchymal stem cells embedded in atelocollagen to the degenerated intervertebral disc.

Intervertebral disc (IVD) degeneration, a common cause of low back pain in humans, is a relentlessly progressive phenomenon with no currently available effective treatment. In an attempt to solve this dilemma, we transplanted autologous mesenchymal stem cells (MSCs) from bone marrow into a rabbit model of disc degeneration to determine if stem cells could repair degenerated IVDs. LacZ expressing MSCs were transplanted to rabbit L2-L3, L3-L4 and L4-L5 IVDs 2 weeks after induction of degeneration. Changes in disc height by plain radiograph, T2-weighted signal intensity in magnetic resonance imaging (MRI), histology, immunohistochemistry and matrix associated gene expressions were evaluated between normal controls (NC) without operations, sham operated with only disc degeneration being induced, and MSC-transplanted animals for a 24-week period. Results showed that after 24 weeks post-MSC transplantation, degenerated discs of MSC-transplanted group animals regained a disc height value of about 91%, MRI signal intensity of about 81%, compared to NC group discs. On the other hand, sham-operated group discs demonstrated the disc height value of about 67% and MRI signal intensity of about 60%. Macroscopic and histological evaluations confirmed relatively preserved nucleus with circular annulus structure in MSC-transplanted discs compared to indistinct structure seen in sham. Restoration of proteoglycan accumulation in MSC-transplanted discs was suggested from immunohistochemistry and gene expression analysis. These data indicate that transplantation of MSCs effectively led to regeneration of IVDs in a rabbit model of disc degeneration as suggested in our previous pilot study. MSCs may serve as a valuable resource in cell transplantation therapy for degenerative disc disease.

Studies on protocadherin-2 expression in the human fetal central nervous system.

Protocadherin (Pcad) is a group of molecules obtained by polymerase chain reaction (PCR) utilizing the sequence that is well preserved in the extracellular domain of cadherin. Sano et al. analyzed Pcad (PC42,43) that had been cloned from rats, and found that it basically had homology to cadherin, but contained more than six cadherin repeats with a completely different intracellular domains (Sano et al. 1993). In the present study, of the Pcad (Pcad-1,2) cloned from a human cDNA library, as-yet-unspecified Pcad-2 was analyzed for expression in the human fetal central nervous system (CNS). Northern blot analysis of adult human tissue showed that Pcad-2 was expressed in the brain and the placenta, and that Pcad-2 mRNA was expressed in actively dividing neural tumor cell lines. Monoclonal antibodies against Pcad-2 were then made, and the CNS of fetuses were immunohistochemically stained. The expression was hardly visible at the 6th week of pregnancy, and began to become visible along the nerve fiber in the brain stem at the 8th week, and spread over the entire brain at the 11th week. At the 18th week, however, expression in the nerve fascicles, which had been visible by that time, was no longer visible or had decreased. These results suggest that Pcad-2 appears relatively early in the critical stage of development of the fetal CNS, and is involved in the induction, fasciculation, and extension of axons.

New technique using galactose-specific lectin for isolation of fetal cells from maternal blood.

To isolate fetal cells from maternal blood, we developed a new method based on galactose-bearing conjugation. Nucleated red blood cells (NRBCs), which highly express galactose on their surface, were selectively attached to a substrate coated with a galactose-containing polymer via soybean agglutinin (SBA), a galactose-specific lectin. Cord blood samples were used to evaluate enrichment efficacy of NRBCs by this method. Blood samples were obtained from 131 pregnant women between 6 and 27 gestational weeks. After preliminary condensation of fetal cells by Ficoll gradient centrifugation, NRBCs were enriched using galactose-positive selection by adjusting SBA concentration. We isolated one to several hundred NRBCs (mean+/-SD, 7.8+/-8.5) in 2.3 ml of peripheral blood samples from 96% of pregnant women. The isolated NRBCs were analyzed by a Y-chromosome FISH probe in eight cases carrying male fetuses. Y-signals were detected in all eight cases and more than half of the NRBCs were off fetal origin. The study demonstrates that our new method using galactose-specific lectin provides effective enrichment of fetal NRBCs allowing non-invasive prenatal diagnosis.