The NLRP3/Caspase-1/Interleukin-1ß Axis Is Active in Human Lumbar Cartilaginous Endplate Degeneration.

BACKGROUND: Modic changes are the MRI signal changes of degenerative lumbar vertebral endplate and which lead to or accelerate intervertebral disc degeneration. NLRP3, caspase-1, and interleukin-1ß (IL-1ß) play a pivotal role in the pathogenesis of many inflammatory diseases, such as osteoarthritis. However, the roles of IL-1ß and its activators caspase-1 and NLRP3 are unclear in the degenerative endplate. QUESTIONS/PURPOSES: We asked: (1) What are the degenerative changes of the histologic features and chondrogenic markers' gene expressions between the cartilaginous endplates of patients with Modic changes and trauma (control)? (2) How does the NLRP3/caspase-1/IL-1ß axis in the cartilaginous endplates of patients with Modic changes compare with control (trauma) specimens? METHODS: Surgical specimens of cartilaginous endplates were divided into Modic changes (n = 56) and the trauma control (n = 16) groups. Hematoxylin and eosin and safranin O staining of cartilaginous endplate tissues were done to evaluate the extracellular matrix. Reverse transcription-polymerase chain reaction was performed on these tissues to investigate mRNA expression of type II collagen (Col II), SOX-9, matrix metalloproteinase-3, and a disintegrin like and metalloproteinase thrombospondin type I motifs-5. NLRP3, caspase-1, and IL-1ß were evaluated by reverse transcription-polymerase chain reaction and immunohistochemistry. RESULTS: Hematoxylin and eosin and safranin O staining showed the extracellular matrix degraded in the cartilaginous endplates of patients with Modic changes but not in the control cartilaginous endplates. Chondrogenic Col II (p = 0.024) and SOX9 (p = 0.053) were downregulated in the Modic changes group compared with the control group. In contrast to the control group, the transcriptional levels of NLRP3 (p < 0.001), caspase-1 (p = 0.054), and IL-1ß (p = 0.001) were all upregulated in the Modic changes group. CONCLUSIONS: The expression of NLRP3, caspase-1, and IL-1ß was upregulated in the patients with low back pain and Modic changes on MRI compared with patients with vertebral burst fracture without degenerative changes on MRI. The data suggest the NLRP3/caspase-1/IL-1ß axis may be implicated in lumbar cartilaginous endplate degeneration. CLINICAL RELEVANCE: The NLRP3/caspase-1/IL-1ß axis is active in cartilaginous endplates of patients with Modic changes and inflammatory cascades can exacerbate the cartilaginous endplate degeneration which may act as a trigger for intervertebral disc degeneration and low back pain. If these findings can be confirmed by others, we hope that new and effective therapy could be developed directed against this target.

Prevention of early bone loss around the prosthesis by administration of anti-osteoporotic agents and influences of collared and non-collared femoral stem prostheses on early periprosthetic bone loss.

The current study aims to investigate the effect of anti-osteoporotic agents of collared and non-collared femoral stem prostheses on periprosthetic bone mineral density (BMD) after total hip arthroplasty (THA). 80 patients who received THA due to femur neck subcapital fractures were involved. The treatment groups were given fosamax, caltrate D and Xianlinggubao for oral administration, whereas the control groups were only given caltrate D. BMD at the greater trochiter around the femoral stem prosthesis and at the femoral shaft 1.5-1.0 cm away from the distal femoral stem was tested using dual-energy X-ray absorptiometry (DEXA) scan. Meanwhile, BMD at the same sites on the uninjured side was also tested. The BMD at both sites in all groups decreased after implantation. In the collared groups, no significant difference was shown between the injured and uninjured sides at 12 days or 3 months (p > 0.001). At 6 months after implantation, significant differences were displayed at both sites between the treatment and control groups (p < 0.001). In the non-collared groups, significant differences were displayed at both sites between the treatment and control groups at 6-months postimplantation (p < 0.001). No significant difference showed between the collared and non-collared groups show any at either site on either side (p > 0.05). DEXA scan can quantitatively determine bone loss around the prosthesis after THA. BMD around the prosthesis is correlated with administration of anti-osteoporotic agents. Fosamax + caltrate D + Xianlinggubao can prevent early bone loss around the prosthesis.

[In vivo effect of nanophase Ti6Al4V on osseointegration: experiment with rabbits].

OBJECTIVE: To evaluate the effect of nanophase Ti6Al4V substrates on the osseointegration in vivo. METHOD: Novel nanophase Ti6Al4V substrates were prepared according to the severe plastic deformation principle. Eighteen New Zealand white rabbits were randomly divided into 3 equal groups with their trochanters of femur exposed and implanted with titanium substrate with common surface (Ti group), nanophase Ti6Al4V substrate (nano-Ti group), and hydroxyapatite-coated substrate (HA group) respectively. Four, 8, and 12 weeks later X-ray films were taken on 6 rabbits from each group, tetracycline and calcein were injected intramuscularly, and one day later the rabbits were sacrificed. The histological changes of the tissue surrounding the implant including the bone kinesics parameter were evaluated; the bone-implant interfaces were examined with scanning electron microscope (SEM) and transmission electron microscope (TEM) respectively. RESULT: Radiographic examinations showed that the bone recovery around the implant in the nano-Ti group was earlier compared to that in the Ti group. Histological examination suggested that the interface osseointegration rates 4, 8, and 12 weeks later of the nano-Ti groups were all significantly higher than those of the Ti group ( all P < 0.01). Strong tetracycline labeling and calcein labeling were observed around the implants in the nano-Ti group, indicating the active form action of new bone. The rates of bone mineralization and deposition 4, 8, and 12 weeks later of the nano-Ti group were higher than those of the Ti group. SEM and TEM examinations showed greater degradation of the surface and much more grains in cells in the HA group as compared to those in the nano-Ti group. The bone mineralization and osseointegration rates 4 weeks later of the HA group were significantly higher than those of the nano-Ti group (both P < 0.05), however, there were no significant differences in the bone mineralization and osseointegration rates 8 weeks later between these 2 groups. The bone mineralization and osseointegration rates 12 weeks later of the nano-Ti group were even higher than those of the HA group. CONCLUSION: The novel nanophase Ti6Al4V substrates improves the bone-implant osseointegration without significant grains of degradation in vivo, suggesting that the novel substrates and nano technology should be further considered for the orthopedic implant applications.

Validation of N-glycan markers that improve the performance of CA19-9 in pancreatic cancer.

Pancreatic cancer (PC) has a high mortality rate because it is usually diagnosed late. Glycosylation of proteins is known to change in tumor cells during the development of PC. The objectives of this study were to identify and validate the diagnostic value of novel biomarkers based on N-glycomic profiling for PC. In total, 217 individuals including subjects with PC, pancreatitis, and healthy controls were divided randomly into a training group (n = 164) and validation groups (n = 53). Serum N-glycomic profiling was analyzed by DSA-FACE. The diagnostic model was constructed based on N-glycan markers with logistic stepwise regression. The diagnostic performance of the model was assessed further in validation cohort. The level of total core fucose residues was increased significantly in PC. Two diagnostic models designated GlycoPCtest and PCmodel (combining GlycoPCtest and CA19-9) were constructed to differentiate PC from normal. The area under the receiver operating characteristic curve (AUC) of PCmodel was higher than that of CA19-9 (0.925 vs. 0.878). The diagnostic models based on N-glycans are new, valuable, noninvasive alternatives for identifying PC. The diagnostic efficacy is improved by combined GlycoPCtest and CA19-9 for the discrimination of patients with PC from healthy controls.

[Research progress in strategy of lateral femoral offset reconstruction in total hip arthroplasty].

As an important indicator of total hip arthroplasty (THA) the rate and degree of offset reconstruction play an important role in improving the prognosis and life quality of patients. The reconstruction of femoral offset is closely related to reserved length of calcar femorale, the head and neck length of prosthesis, angle degree of neck shaft and whether lower limb is isometric. Reconstruction strategy includes making a meticulous and standard measurement before the surgery, predicting the reserved length of calcar femorale, selecting a prosthesis with approximate anatomical neck-shaft angle and reconstructing offset by adjusting the head and neck length of the prosthetic during the operation. The aim of this article was to introduce the research progress and influence of offset on hip function, prosthetic wear and postoperative complications such as pain, limp and unequal leg length, and to discuss the reconstruction strategy.

Targeting Yes-associated Protein with Evolved Peptide Aptamers to Disrupt TGF-ß Signaling Pathway: Therapeutic Implication for Bone Tumor.

The binding of transcription coactivator Yes-associated protein (YAP) to Smad transcription factors is an important event in activating transforming growth factor-ß (TGF-ß) signaling pathway, which is involved in the tumorigenicity and metastasis of bone tumor. Design of peptide aptamers to disrupt YAPSmad interaction has been established as a promising approach for bone tumor therapy. Here, an evolution strategy was used to optimize Smad-derived peptides for high potency binding to YAP WW2 domain, resulting in an improved peptide population, from which those high-scoring candidates were characterized rigorously using molecular dynamics (MD) simulations and interaction free energy calculations. With the computational protocol we were able to generate a number of potential domain binders, which were then substantiated by using fluorescence spectroscopy assay. Subsequently, the complex structure of YAP WW2 domain with a high-affinity peptide was modeled and examined in detail, which was then used to guide structure-based peptide optimization to obtain several strong domain binders. Structural and energetic analysis revealed that electrostatic complementarity is primarily responsible for domainpeptide recognition, while other nonbonded interactions such as hydrogen bonding and salt bridges can contribute significantly to the recognition specificity.

Investigation on the DNA repaired gene polymorphisms and response to chemotherapy and overall survival of osteosarcoma.

The aim of the present study was to evaluate the influence of polymorphisms in NER and HRR pathways on the response to cisplatin-based treatment and clinical outcome in osteosarcoma patients. 214 osteosarcoma patients treated with cisplatin-based chemotherapy were collected between January 2008 and January 2011. Genotypes of ERCC1 rs11615, ERCC2 rs1799793 and rs13181, NBN rs709816, RAD51 rs1801320, and XRCC3 rs861539 were conducted by Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP) assay. By conditional logistic regression analysis, patients carrying CC genotype of ERCC1 rs11615 showed a significant more good responder than TT genotype, and the OR (95% CI) was 2.51 (1.02-6.85). In the Cox proportional hazards model, after adjusting for potential confounding factors, we found that individuals carrying CC genotype of ERCC1 rs11615 was associated with decreased risk of death from osteosarcoma, and the HR (95% CI) was 0.43 (0.15-0.93). In conclusion, our results suggest that ERCC1 rs11615 polymorphism in the DNA repair pathways play an important role in the response to chemotherapy and overall survival of osteosarcoma.

Alternative splicing of NUMB, APP and VEGFA as the features of pancreatic ductal carcinoma.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is the most common form of malignancy in pancreatic carcinoma. Here we report our discovery on the correlations between transcriptional alternative splicing (AS) of NUMB, APP, VEGFA and PDAC in patients. METHODS: The expression of NUMB, APP, VEGFA from patient samples was determined by qRT-PCR. AS of these genes was examined through laser induced fluorescence capillary electrophoresis. Correlation between the AS of the genes and results from clinical laboratory examinations were analyzed. Expression of NOTHC1 and NOTCH4 as downstream target genes was examined by qRT-PCR and Western blot. RESULTS: Quantitative results indicated that expression of NUMB was significantly lower in tumor tissues (TT) than in para-tumor tissues (TP) (P<0.05), while APP (P<0.01) and VEGFA (P<0.05) were significantly higher. AS transcript percentage of NUMB PRR(S) was lower in TT than TP (P<0.05). AS transcript percentage of VEGFA (105+185) was significantly lower in TT than TP (P<0.05) compared to higher expression of VEGFA (206+338) (P<0.05). Regression analysis indicated that AS transcript of NUMB PRR(L) correlated with tumor size (P<0.01), while AS transcripts of APP and VEGFA correlated with results of laboratory examinations. To reveal the correlation between AS and its downstream targets, NOTCH1 and NOTCH4 were selected as NUMB gene targets and detected to be significantly higher in TT than TP (P<0.05). CONCLUSION: Alternative splicing of APP, VEGFA and NUMB may play an important role in pathogenesis of pancreatic ductal adenocarcinoma. Among the 3 genes, PRR(L) form of NUMB gene is highly expressed in TT and positively correlated with tumor size, while PRR(S) is lacking in TT and negatively correlated with NOTCH expression suggesting that PRR(S) might be protective in tumorogenesis and shows NOTCH pathway down regulation ability.

[Digital anatomy of the perforator flap in the thigh].

OBJECTIVE: To provide algorithmic morphological data that enables safe elevation of the flow-through perforator flap, chimeric perforator flap in the thigh. METHODS: 15 fresh cadavers were injected with a modified lead oxide-gelatin mixture for three-dimensional reconstruction using a spiral computed tomography scanner and specialized volume-rendering software (MIMICS). All of specimens were then dissected by layers. Angiography and photography were used to document the precise course, size, location, and type of individual perforators in the thigh region. The surface areas of cutaneous territories and perforator zones were measured and calculate with Photoshop and Scion Image. RESULTS: The main artery supplying the thigh is femoral artery. There are (41 +/- 4.0) perforators whose outer diameters > or = 0.5 mm. These perforators have a superficial pedicle length of (4.2 +/- 1.7) cm. The average outer diameter is (0.8 +/- 0.1) mm. Each perforator supplies an average area of (44 +/- 6.4) cm2. There are lots of truly anastomoses among perforaors to form a subcutaneous network in the thigh. CONCLUSIONS: The volume rendering technique is very useful for showing the subcutaneous network and preoperative flap design. The thigh appears to have the greatest potential for harvesting new or modified perforator flaps, especially, flow-through perforator flap or chimeric perforator flap.

Improved osteoblast proliferation, differentiation and mineralization on nanophase Ti6Al4V.

BACKGROUND: Previous studies have demonstrated increased functions of osteoblasts on nanophase materials compared to conventional ceramics or composites. Nanophase materials are unique materials that simulate dimensions of constituent components of bone as they possess particle or grain sizes less than 100 nm. However, to date, interactions of osteoblasts on nanophase materials compared to conventional metals remain to be elucidated. The objective of the present in vitro study was to synthesize nanophase metals (Ti6Al4V), characterize, and evaluate osteoblast functions on Ti6Al4V. Such metals in conventional form are widely used in orthopedic applications. METHODS: In this work, nanophase Ti6Al4V surfaces were processed by the severe plastic deformation (SPD) principle and used to investigate osteoblast long-term functions. Primary cultured osteoblasts from neonatal rat calvaria were cultured on both nanophase and conventional Ti6Al4V substrates. Cell proliferation, total protein content, and alkaline phosphatase (ALP) activity were evaluated after 1, 3, 7, 10 and 14 days. Calcium deposition, gene expression of type I collagen (Col-I), osteocalcin (OC), osteopontin (OP) and the production of insulin-like growth factor-I (IGF-I) and transforming growth factor-beta 1 (TGF-ß1) were also investigated after 14 days of culture. RESULTS: Functions of osteoblasts including proliferation, synthesis of protein, and ALP activity were improved on the nanophase compared to the conventional Ti6Al4V. The expression of Col-I, OC and OP mRNA was also increased on nanophase Ti6Al4V after 14 days of culture. Calcium deposition was the same; the average number of the calcified nodules on the two Ti6Al4V surfaces was similar after 14 days of culture; however, highly significant size calcified nodules on the nanophase Ti6Al4V was observed. Of the growth factors examined, only TGF-ß1 showed a difference in production on the nanophase surface. CONCLUSION: Nanophase Ti6Al4V surfaces improve proliferation, differentiation and mineralization of osteoblast cells and should be further considered for orthopedic implant applications.

[Treatment of osteoporotic distal femur fractures with less invasive stabilizing system (LISS) and high strength injectable graft].

OBJECTIVE: To evaluate the clinical results of less invasive stabilizing system (LISS) and high strength injectable graft in the treatment of osteoporotic distal femur fractures. METHODS: From Feb. 2005 to Feb. 2008, 26 cases (15 males, 11 females) of osteoporotic distal femur fractures were treated with less invasive stabilizing system (LISS) and high strength injectable graft. The mean age of the patients was 68.5 years (ranging from 59 to 81 years). According to AO classification,there were 9 cases type A3, 6 cases type C1, 7 cases type C2, 4 cases type C3. RESULTS: The mean operation time was (110 +/- 15) min (ranging from 90 to 135 min). The patients were followed-up for from 12 to 28 months (averaged 18 months). The mean healing time was 20.5 weeks(ranging from 16.5 to 28 weeks). No deep infection, fixation loosening, breakage or failure of implants were observed after the operations. According to Rasmussen radiological evaluation,the results showed 19 cases for "excellent", 7 cases for "good". One year postoperatively, the mean ROM of the knees was 2 degrees to 125 degrees, the HSS knee score was from 59 to 99 points with average of (86.5 +/- 8.2) points. According to HSS scoring system, the results showed 22 cases for "excellent", 2 cases for "good", 1 for "fair" and 1 for "poor". CONCLUSION: The less invasive stabilizing system (LISS) and high strength injectable graft is an effective way for the treatment of osteoporotic distal femur fractures.