Po-Liang Lai

Use of fluorescence labeled mesenchymal stem cells in pluronic F127 and porous hydroxyapatite as a bone substitute for posterolateral spinal fusion

Posterolateral spinal fusion is used to treat patients with degenerative spinal disorders. We investigated the effectiveness of a mesenchymal stem cell (MSC)/Pluronic F127/Interpore hybrid graft for spinal fusion in rabbits. Spinal fusion was examined using radiography, manual palpation, computed tomography (CT), torsional loading tests, and histological analysis. Using a PKH fluorescence labeling system, we also examined whether the newly formed bone was derived from the transplanted MSCs. We found that the MSCs adhered to the Interpore surface and within its pores, and differentiated into osteoblasts. Radiographs and CT images showed a continuous bone bridge and a satisfactory fusion mass incorporated into the transverse processes. The results of manual palpation and biomechanical data did not differ significantly from an autograft group. Histology from both groups revealed the presence of fibrous tissue, cartilage, and endochondral ossification in the gaps between the grafted fragments. In both groups, the degree of mature bone formation was greater at 12 weeks than at 6 weeks after grafting. Quantitative histomorphometry revealed no significant differences between the two groups at either time point. In situ tracing of the PKH 67‐labeled MSCs indicated that the transplanted MSCs were partly responsible for the new bone formation in both the repaired transverse processes and the grafted fragments. Thus, the MSC/Pluronic F127/Interpore hybrid graft could be used effectively to achieve posterolateral spinal fusion.

Beneficial effects of hyperbaric oxygen on human degenerated intervertebral disk cells via suppression of IL-1β and p38 MAPK signal.

Nucleus pulposus cells (NPCs) from degenerating disks produce catabolic and inflammatory factors, including interleukin (IL)‐1, nitric oxide (NO), prostaglandin E2 (PGE‐2), and matrix metalloproteinaes (MMPs). An imbalance between MMPs and tissue inhibitors of matrix metalloproteinases (TIMPs) has been proposed to exist in the degenerating disk. This study evaluates the effects of hyperbaric oxygen (HBO) on the human degenerated NPCs. NPCs were maintained in alginate bead culture. All hyperoxic cells were exposed to 100% O2 at 2.5 atmospheres absolute (ATA) in a hyperbaric chamber. p38 MAPK phosphorylation of the NPCs was detected using the phosphor‐kinase array kit. RNA was isolated for real‐time quantitative polymerase chain reaction (Q‐PCR) analysis of aggrecan and type II collagen gene expression. The amounts of IL‐1β, NO, PGE‐2, MMP‐3, and TIMP‐1 in the conditioned media were quantified by enzyme‐linked immunosorbent assay (ELISA). Our data showed that HBO treatment decreased expression of IL‐1β, increased the gene expression of aggrecan and type II collagen, suppressed the phosphorylation of p38 MAPK, decreased NO, PGE‐2, and MMP‐3, and increased TIMP‐1 expression in NPCs as compared with the atmospheric treatment. These results support the hypothesis that IL‐1β and the p38 MAPK signal may be responsible for many of the inflammatory and catabolic changes seen in the human disk degeneration, and support our proposal that HBO treatment‐induced increase of the anabolic factor (TIMP‐1)/catabolic factor (MMP‐3) ratio may provide a therapeutic approach to slow the course of intervertebral disk degeneration.

Advanced glycation end products in degenerative nucleus pulposus with diabetes

Diabetes mellitus (DM) has been clinically proved as a risk factor of disc degeneration, and the accumulation of advanced glycation end products (AGEs) is known to be potentially involved in diabetes. The purpose of this study is to investigate the effect of AGEs in the degeneration process of diabetic nucleus pulposus (NP) in rats and humans. Diabetic NP cells from rat coccygeal discs were treated with different concentrations of AGEs (0, 50, and 100u2009µg/ml) for 3 days, and mRNA expressions of MMP‐2 and RAGE were measured by real‐time RT‐PCR. In addition, conditioned medium from NP cells was used to analyze protein expression of MMP‐2 activity and ERK by gelatin zymography and Western blot. These experiments were repeated using human intervertebral disc samples. The immunohistochemical expression of AGEs was significantly increased in diabetic discs. In response to AGEs, an increase of MMP‐2, RAGE, and ERK at both mRNA and protein expression levels was observed in diabetic NP cells. The findings suggest that AGEs and DM are associated with disc degeneration in both species. Hyperglycemia in diabetes enhances the accumulation of AGEs in the NP and triggers disc degeneration.

Simultaneous anterior dislocation of the shoulder and fracture of the ipsilateral humeral shaft

Summary. Two patients with anterior dislocation of the shoulder and ipsilateral fracture of the shaft of the humerus have been studied and the mechanism of their injuries has been documented. Closed reduction of the dislocations was performed under anaesthesia during surgery for humeral fixation with a dynamic compression plate. The fractures and dislocations healed without any problems at 6 to 9 months postoperatively. At recent follow-up, one patient had returned to work and regained normal mobility. The other patient had the sequelae of a brachial plexus injury. The literature on this subject is reviewed.Résumé. Deux cas de luxation de l’épaule avec fracture associèe de la diaphyse humeriale ont été rapportés. Le mécanisme des blessures a été décrit. Une réduction fermée de la luxation a été réalisée sous anesthésie pendant l’opération chirurgicale. Pour la fixation, la méthode utilisée fut celle de la mise en place d’une plaque de compression dynamique après réduction ouverte. La fracture et la luxation ont été guéries sans problème trois mois après l’opération. Après un suivi récent, l’un des patients a été autoriséà reprendre son travail sans restriction, et a recouvré une mobilite normalé. Le second conserve des séquelles de sa blessure du plexus brachial. La littérature sur ce sujet est révisée.

Hyperbaric oxygen treatment suppresses MAPK signaling and mitochondrial apoptotic pathway in degenerated human intervertebral disc cells

Nucleus pulposus cells (NPCs) from degenerating discs produce catabolic and inflammatory factors, including interleukin (IL)‐1 and nitric oxide (NO). Enhanced production of NO has been implicated in the apoptosis of degenerating disc cells. This study evaluates the effects of hyperbaric oxygen (HBO) on degenerated human NPCs. All hyperoxic cells were exposed to 100% O2 at 2.5 atmospheres absolute (ATA). Phosphorylation of extracellular signal‐regulated kinase 1/2 (ERK1/2), c‐Jun N‐terminal kinase (JNK), and p38 mitogen‐activated protein kinase (MAPK) in NPCs was detected using the phosphor‐kinase array kit. RNA was isolated for real‐time polymerase chain reaction (PCR) analysis of aggrecan and type II collagen gene expression. The levels of IL‐1β and NO were quantified by enzyme‐linked immunosorbent assay (ELISA). To identify the HBO‐induced anti‐apoptotic pathways, expression of Bcl‐2 and Bax proteins as well as activation of cysteine‐containing aspartate‐specific proteases (caspases) 3, 8, and 9 was evaluated using Western blotting after HBO treatment. Our data showed that HBO treatment decreased the expression of IL‐1β, suppressed phosphorylation of ERK1/2, JNK, and p38 MAPK, decreased synthesis of NO, and increased the gene expression of aggrecan and type II collagen in NPCs as compared with the atmospheric treatment. HBO up‐regulated the ratio of Bcl‐2 to Bax expression and reduced the activity of caspases 9 and 3 but not of caspase 8, indicating a selective effect over the mitochondrial apoptosis pathway in degenerated NPCs. These results support our hypothesis that HBO treatment suppresses MAPK signaling and mitochondrial apoptotic pathway in degenerated human intervertebral disc cells.

Increased periostin gene expression in degenerative intervertebral disc cells.

BACKGROUND CONTEXTnDisc degeneration is a multifactorial disease that may cause clinical symptoms such as chronic back pain or radiculopathy in the extremities. Periostin, an extracellular matrix protein involved in the process of fibrosis, expressed in tissues subjected to mechanical stress such as intervertebral disc. However, the expression of periostin during disc degeneration has not yet been studied.nnnPURPOSEnThe aim of this study is to elucidate the difference in gene expression profiles between degenerative and nondegenerative intervertebral discs for a better understanding of disc degeneration.nnnSTUDY DESIGNnDegenerative and nondegenerative nucleus pulposus cells were isolated from elderly patients with degenerative disc disease and younger patients with adolescent idiopathic scoliosis, respectively.nnnMETHODSnAffymetrix GeneChip Human arrays were used to derive gene expression profiles for disc degeneration, and gene expressions of periostin and other degeneration-related markers were confirmed by reverse transcription-polymerase chain reaction (RT-PCR), real-time RT-PCR, and western blot analysis. Immunohistochemical analysis of periostin and Gomori trichrome stain was performed to show the relationship of periostin, fibrosis, and disc degeneration. The mechanical stress experiment was designed to demonstrate the relationship of periostin, stress, and disc degeneration.nnnRESULTSnFourteen genes were identified to express at significantly different levels between degenerative and nondegenerative groups. An increase of periostin gene expression was observed in human degenerative nucleus pulposus cells for the messenger RNA and protein levels. Histological examination demonstrated an increased positive staining of periostin in degenerative discs from human tissues and rat needle-punctured tails and more fibrosis with architectural disorder and fragmentation in human degenerative disc as compared with nondegenerative discs. The expression of periostin was significantly induced by stress in human degenerative nucleus pulposus cells but not in nondegenerative cells.nnnCONCLUSIONSnThis study demonstrates for the first time an upregulation of periostin in addition to the expression levels of Type I collagen and matrix metalloproteinase-2 in human disc degeneration. It suggests that periostin may be a candidate gene that shows promise as a new prognostic marker and a therapeutic target that is worth further study to expand our knowledge of its role in disc degeneration.

Increased sulfatase 1 gene expression in degenerative intervertebral disc cells

Sulfatase 1 (SULF1) plays a key role in cell signaling involving in cell growth, differentiation, proliferation, and migration. Abnormal SULF1 expression has been implicated in the development of various cancers and diseases of the skeletal and nervous systems. The present study aims to examine the difference in SULF1 expression between degenerative and non‐degenerative intervertebral discs (IVDs) to provide an enhanced understanding of disc degeneration. Degenerative and non‐degenerative disc tissues were surgically harvested from patients and experimental rats. Disc degeneration‐specific genes were identified by microarray analysis. The gene expression of SULF1 was measured by sulfatase assay, reverse transcription‐polymerase chain reaction (RT‐PCR), real‐time RT‐PCR, and western blotting. Also, the presence of SULF1 in human and rat discs was confirmed by immunohistochemistry. More specifically in human cells, an increase of SULF1 gene expression was observed in degenerative cells at both mRNA and protein levels, as well as in time‐ and dose‐dependent manner in response to TNF‐α treatment. Increased staining of SULF1 was detected in degenerative discs compared to non‐degenerative discs for humans and rats. These findings show an upregulation of SULF1 in degenerative discs for the first time, and suggest that there is a link between SULF1 and disc degeneration.

Surgical treatment of achondroplasia with thoracolumbar kyphosis and spinal stenosis—a case report

A 13-year-old boy suffered from low back weak-ness and bilateral lower extremity numbness for many years. In June 2003, intermittent claudica-tion appeared, the boy could only walk for 5 min, and he was seen at our clinic. Physical examina-tion revealed a short stature of only 126 cm, promi-nent frontal bossing, nose-bridge depression, short limbs with long trunk, and thoracolumbar kypho-sis (Figure 1). No neurological deficit was noted. Radiographs revealed scoliosis and reduced inter-pediclar distance of the lumbar spine (Figure 2). An anterior wedged deformity of the L1 body with prominent thoracolumbar kyphosis was observed with a T12-L2 kyphosis angle of 55° (Figure 3). MRI of the thoracolumbar spine identified a spinal canal stenosis (diameter 10 mm) below the T11 level (Figure 4). One stage anterior L1 corpectomy with interbody fusion was performed, followed by posterior decompression with pedicle screw

Unplanned revision spinal surgery within a week: a retrospective analysis of surgical causes

BackgroundThe need for revision surgery after a spinal surgery can cause a variety of problems, including reduced quality of life for the patient, additional medical expenses, and patient-physician conflicts. The purpose of this study was to evaluate the causes of unplanned revision spinal surgery within a week after the initial surgery in order to identify the surgical issues most commonly associated with unplanned revision surgery.MethodsWe retrospectively reviewed the medical records of all patients at who received a spinal surgery at a regional medical center from July 2004 to April 2011 in order to identify those who required a revision surgery within one week of their initial surgery. Patients were excluded if they received a vertebroplasty, kyphoplasty, or nerve block surgery, because those surgeries are one-day surgeries that do not require hospital admission. In addition, patients with a primary diagnosis of wound infection were also excluded since reoperations for infection control can be expected.ResultsThe overall incidence of unplanned revision spinal surgery during the time period covered by this review was 1.12xa0% (116/10,350 patients). The most common surgical causes of reoperation were screw malposition (41 patients), symptomatic epidural hematoma (27 patients), and inadequate decompression (37 patients). Screw malposition was the most common complication, with an incidence rate of 0.82xa0%. Screw instrumentation was significantly associated with revision surgery (pu2009=u20090.023), which suggests that this procedure carried a greater risk of requiring revision. The mean time interval to reoperation for epidural hematomas was significantly shorter than the intervals for other causes of revision spinal surgery (pu2009<u20090.001), which suggests that epidural hematoma was more emergent than other complications. Also, 25.93xa0% of patients who underwent hematoma removal experienced residual sequelae; this percentage was significantly higher than for other surgical causes of revision spinal surgery (pu2009=u20090.013).ConclusionsThe results suggest that to avoid the need for reoperation, screw malposition, inadequate decompression, and epidural hematoma are the key surgical complications to be guarded against. Accordingly, adequate decompression, epidural hematoma prevention, and proper pedicle screw placement may help reduce the incidence of revision surgery.

Correlation of blood bone turnover biomarkers and Wnt signaling antagonists with AS, DISH, OPLL, and OYL

BackgroundWnt signaling plays an important role in development and maintenance of many organs and tissues. The most-studied secreted Wnt inhibitors are sclerostin (SOST), Dickkopf-related protein 1 (DKK-1), and secreted frizzled related protein 1 (SFRP-1) which play important roles in bone turnover. The present study investigated the relationship between serum Wnt inhibitors and diseases with excessive ossification structures, such as ossification of posterior longitudinal ligament (OPLL), ankylosing spondylitis (AS), diffuse idiopathic skeletal hyperostosis (DISH), and ossification of yellow ligament (OYL).MethodsTwenty-five patients with AS, DISH, OPLL, or OYL were recruited in this study. Fasting peripheral blood samples were collected from all patients and nine controls. Various biomarkers of bone turnover including osteocalcin (OSC), osteoprotegerin (OPG), SFRP-1, DKK-1, and SOST were investigated.ResultsOur data showed that serum levels of OSC were higher, but Dkk-1 levels were lower in AS, DISH, OPLL, and OYL patients than those in the controls. Serum levels of SFRP-1 were significantly higher in DISH patients than those in the controls. Serum levels of SOST were significantly higher in DISH and OPLL patients than both levels in the controls. Serum levels of OPG were lower in AS patients than those in the controls. Serum levels of OSC were higher in the OPLL patients than those in the AS patients. Serum levels of DKK-1, SFRP-1, SOST, and OPG were not significantly different between the different disease groups.ConclusionsIn this exploratory study, both OSC and DKK-1 levels are correlated with the clinical conditions associated with excessive ossification, indicating that blood OSC and DKK-1 levels may serve as diagnostic biomarkers for AS, DISH, OPLL, and OYL. These findings may also help discover potential drug therapies for management of these diseases in the future.