bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic modification of chondrocytes with insulin-like growth factor-1 enhances cartilage healing in an equine model
Authors: Goodrich L. R. , Hidaka C. , Robbins P. D. , Evans C. H. , Nixon A. J. 
Published: May 2007

Gene therapy with insulin-like growth factor-1 (IGF-1) increases matrix production and enhances chondrocyte proliferation and survival in vitro. The purpose of this study was to determine whether arthroscopically-grafted chondrocytes genetically modified by an adenovirus vector encoding equine IGF-1 (AdIGF-1) would have a beneficial effect on cartilage healing in an equine femoropatellar joint model.A total of 16 horses underwent arthroscopic repair of a single 15 mm cartilage defect in each femoropatellar joint. One joint received 2 × 107AdIGF-1 modified chondrocytes and the contralateral joint received 2 × 107naive (unmodified) chondrocytes. Repairs were analysed at four weeks, nine weeks and eight months after surgery. Morphological and histological appearance, IGF-1 and collagen type II gene expression (polymerase chain reaction, in situ hybridisation and immunohistochemistry), collagen type II content (cyanogen bromide and sodium dodecyl sulphate-polyacrylamide gel electrophoresis), proteoglycan content (dimethylmethylene blue assay), and gene expression for collagen type I, matrix metalloproteinase (MMP)-1, MMP-3, MMP-13, aggrecanase-1, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) and TIMP-3 were evaluated.Genetic modification of chondrocytes significantly increased IGF-1 mRNA and ligand production in repair tissue for up to nine weeks following transplantation. The gross and histological appearance of IGF-1 modified repair tissue was improved over control defects. Gross filling of defects was significantly improved at four weeks, and a more hyaline-like tissue covered the lesions at eight months. Histological outcome at four and nine weeks post-transplantation revealed greater tissue filling of defects transplanted with genetically modified chondrocytes, whereas repair tissue in control defects was thin and irregular and more fibrous. Collagen type II expression in IGF-1 gene-transduced defects was increased 100-fold at four weeks and correlated with increased collagen type II immunoreaction up to eight months.Genetic modification of chondrocytes with AdIGF-1 prior to transplantation improved early (four to nine weeks), and to a lesser degree long-term, cartilage healing in the equine model.The equine model of cartilage healing closely resembles human clinical cartilage repair. The results of this study suggest that cartilage healing can be enhanced through genetic modification of chondrocytes prior to transplantation.
Healing of full-thickness defects of the articular cartilage in rabbits using fibroblast growth factor-2 and a fibrin sealant
Authors: Ishii I. , Mizuta H. , Sei A. , Hirose J. , Kudo S. , Hiraki Y. 
Published: May 2007

We have investigated in vitro the release kinetics and bioactivity of fibroblast growth factor-2 (FGF-2) released from a carrier of fibrin sealant. In order to evaluate the effects of the FGF-2 delivery mechanism on the repair of articular cartilage, full-thickness cylindrical defects, 5 mm in diameter and 4 mm in depth, which were too large to undergo spontaneous repair, were created in the femoral trochlea of rabbit knees. These defects were then filled with the sealant. Approximately 50% of the FGF-2 was released from the sealant within 24 hours while its original bioactivity was maintained. The implantation of the fibrin sealant incorporating FGF-2 successfully induced healing of the surface with hyaline cartilage and concomitant repair of the subchondral bone at eight weeks after the creation of the defect. Our findings suggest that this delivery method for FGF-2 may be useful for promoting regenerative repair of full-thickness defects of articular cartilage in humans.
Alternating cervical laminoplasty for cervical spondylotic myelopathy
Authors: Iencean S. M. 
Published: May 2007

We present a novel method of performing an ‘open-door’ cervical laminoplasty. The complete laminotomy is sited on alternate sides at successive levels, thereby allowing the posterior arch to be elevated to alternate sides. Foraminotomies can be carried out on either side to relieve root compression. The midline structures are preserved. We undertook this procedure in 23 elderly patients with a spondylotic myelopathy. Each was assessed clinically and radiologically before and after their operation. Follow-up was for a minimum of three years (mean 4.5 years; 3 to 7). Using the modified Japanese Orthopaedic Association scoring system, the mean pre-operative score was 8.1 (6 to 10), which improved post-operatively to a mean of 12.7 (11 to 14). The mean percentage improvement was 61% (50% to 85.7%) after three years. The canal/vertebral body ratio improved from a mean of 0.65 (0.33 to 0.73) pre-operatively to 0.94 (0.5 to 1.07) postoperatively. Alternating cervical laminoplasty can be performed safely in elderly patients with minimal morbidity and good results.
IGF-I Receptor Is Required for the Anabolic Actions of Parathyroid Hormone on Bone
Authors: Wang Yongmei , Nishida Shigeki , Boudignon Benjamin M , Burghardt Andrew , Elalieh Hashem Z , Hamilton Michelle M , Majumdar Sharmila , Halloran Bernard P , Clemens Thomas L , Bikle Daniel D 
Published: May 2007

Abstract
We showed that the IGF-IR–null mutation in mature osteoblasts leads to less bone and decreased periosteal bone formation and impaired the stimulatory effects of PTH on osteoprogenitor cell proliferation and differentiation.
Introduction: This study was carried out to examine the role of IGF-I signaling in mediating the actions of PTH on bone.
Materials and Methods: Three-month-old mice with an osteoblast-specific IGF-I receptor null mutation (IGF-IR OBKO) and their normal littermates were treated with vehicle or PTH (80 μg/kg body weight/d for 2 wk). Structural measurements of the proximal and midshaft of the tibia were made by μCT. Trabecular and cortical bone formation was measured by bone histomorphometry. Bone marrow stromal cells (BMSCs) were obtained to assess the effects of PTH on osteoprogenitor number and differentiation.
Results: The fat-free weight of bone normalized to body weight (FFW/BW), bone volume (BV/TV), and cortical thickness (C.Th) in both proximal tibia and shaft were all less in the IGF-IR OBKO mice compared with controls. PTH decreased FFW/BW of the proximal tibia more substantially in controls than in IGF-IR OBKO mice. The increase in C.Th after PTH in the proximal tibia was comparable in both control and IGF-IR OBKO mice. Although trabecular and periosteal bone formation was markedly lower in the IGF-IR OBKO mice than in the control mice, endosteal bone formation was comparable in control and IGF-IR OBKO mice. PTH stimulated endosteal bone formation only in the control animals. Compared with BMSCs from control mice, BMSCs from IGF-IR OBKO mice showed equal alkaline phosphatase (ALP)+ colonies on day 14, but fewer mineralized nodules on day 28. Administration of PTH increased the number of ALP+ colonies and mineralized nodules on days 14 and 28 in BMSCs from control mice, but not in BMSCs from IGF-IR OBKO mice.
Conclusions: Our results indicate that the IGF-IR null mutation in mature osteoblasts leads to less bone and decreased bone formation, in part because of the requirement for the IGF-IR in mature osteoblasts to enable PTH to stimulate osteoprogenitor cell proliferation and differentiation.
Longevity of Ceratomyxa shasta and Parvicapsula minibicornis Actinospore Infectivity in the Klamath River
Authors: Foott J. Scott , Stone R. , Wiseman E. , True K. , Nichols K. 
Published: May 2007

Abstract
Infectious Ceratomyxa shasta and Parvicapsula minibicornis actinospores were present in Klamath River samples collected in April, May, and June 2005. Juvenile Chinook salmon Oncorhynchus tshawytscha exposed to river water maintained at the ambient Klamath River temperature for 0, 4, 24, 72, and 168 h (7 d) developed asymptomatic infections from both parasites. Elevated water temperature (18°C) in June may have reduced actinospore viability, as both C. shasta and P. minibicornis infection markedly declined in fish exposed for over 72 h. As judged by the prevalence of infection for both parasites, the number of infectious actinospores tended to increase or remain steady through the spring. Ceratomyxa shasta infections were characterized by the presence of a few trophozoites within granulomatous foci in mesentery adipose tissue and were consistently observed outside of the intestine. Similarly, low numbers of P. minibicornis were observed in kidney glomeruli and tubules but were not associated with inflammation. Parvicapsula minibicornis DNA was consistently detected by quantitative real-time polymerase chain reaction in filtered water samples collected each month and from each time posttransfer. These data and the high prevalence of infection observed in the exposed fish indicate that P. minibicornis actinospores were at a relatively high concentration in the river during the spring. In contrast, C. shasta DNA was only detected in half of the water sample sets and its detection did not correspond well to C. shasta infectivity. An approximately threefold increase in river flow from the April to the May water collection was not associated with a decline in either the detection of actinospores (particularly for P. minibicornis) or the prevalence of infection for both parasites. Actinospores of these myxosporean parasites have the potential to infect salmonids for at least 7 d after release from the alternate polychaete host.
Mycobacterial Infections in Striped Bass from Delaware Bay
Authors: Ottinger C. A. , Brown J. J. , Densmore C. L. , Starliper C. E. , Blazer V. S. , Weyers H. S. , Beauchamp K. A. , Rhodes M. W. , Kator H. , Gauthier D. T. , Vogelbein W. K. 
Published: May 2007

Abstract
Eighty striped bass Morone saxatilis were obtained from Delaware Bay using commercial gill nets set adjacent to Woodland Beach (n = 70) and Bowers Beach (n = 10) in December 2003. Fish were examined for gross lesions. Total lengths (TLs) and eviscerated weights were determined to calculate condition factors (K). Portions of spleens were aseptically harvested for bacterial culture, and portions of spleens, kidneys (anterior and posterior), livers, and gonads were obtained for histological examination. The size distribution of the striped bass was relatively homogeneous; the mean TL was about 600 mm for all samples. Mean K exceeded 0.95 in all samples and was not significantly different (P &gt; 0.05) among samples. Significant differences in mycobacterial infection prevalence (P ≤ 0.05) were observed among samples; samples obtained at Woodland Beach (WB) on December 10 (53.8%, n = 13) and December 17 (7.1%, n = 42) exhibited the most striking differences in prevalence. Mycobacterial infection intensity ranged from 1 × 102 to 1 × 107 colony-forming units per gram of spleen. Acanthocephalan infection prevalence and intensity, non-acid-fast bacterial infection prevalence, and fish sex ratio were also significantly different among the samples (P ≤ 0.05). Similar to the mycobacterial infections, differences in sex ratio, acanthocephalan infection, and non-acid-fast bacterial infection were observed between the WB samples taken on December 10 and 17. However, no significant associations (P &gt; 0.05) were observed between sex ratio or these infections and mycobacterial infection. The differences in bacterial and parasite infection prevalence and intensity and fish sex ratio in some samples indicate that these fish had a different history and that the epizootiology of mycobacterial infection in striped bass from Delaware Bay may be relatively complex.
Pathological Effects Caused by Chronic Treatment of Rainbow Trout with Indomethacin
Authors: Lovy Jan , Speare David J. , Wright Glenda M. 
Published: May 2007

Abstract
The purpose of this study was to determine adequate dose ranges and to test for side effects associated with chronic treatment of fish with indomethacin. Rainbow trout Oncorhynchus mykiss were orally treated with indomethacin at various nominal concentrations: a negative control (0 mg/kg) and low (5 mg/kg), medium (10 mg/kg), and high doses (15 mg/kg) daily for 30 d. A dose-associated mortality was observed, as cumulative mortality was 3, 13, and 33%, respectively, in the three indomethacin dose groups. No lesions were observed grossly or with histopathology in the control and low-dose treatment groups. Gross lesions were observed in the medium- and high-dose groups, including skin ulcers, abdominal distension, and necrosis of abdominal wall muscle. Histopathology of fish in the medium- and high-dosage groups revealed severe granulomatous peritonitis in which a large number of foreign body type giant cells were present around proteinaceous and plant material. The inflammatory response spread from the peritoneum through the somatic muscle to the epidermis, causing lesions within all layers of the skin. A large number of bacteria were noted within the peritonitis, observed both intracellularly and in large aggregates extracellularly. Perforations occurred within the anterior intestine, and the thick muscularis layer was replaced with inflammatory tissue. The present investigation shows that chronic indomethacin treatment produces gastrointestinal side effects in rainbow trout similar to those seen in mammals.
Increasing hierarchical complexity throughout the history of life: phylogenetic tests of trend mechanisms
Authors: Marcot Jonathan D. , McShea Daniel W. 
Published: May 2007

The history of life is punctuated by a number of major transitions in hierarchy, defined here as the degree of nestedness of lower-level individuals within higher-level ones: the combination of single-celled prokaryotic cells to form the first eukaryotic cell, the aggregation of single eukaryotic cells to form complex multicellular organisms, and finally, the association of multicellular organisms to form complex colonial individuals. These transitions together constitute one of the most salient and certain trends in the history of life, in particular, a trend in maximum hierarchical structure, which can be understood as a trend in complexity. This trend could be produced by a biased mechanism, in which increases in hierarchy are more likely than decreases, or by an unbiased one, in which increases and decreases are about equally likely. At stake is whether or not natural selection or some other force acts powerfully over the history of life to drive complexity upward.Too few major transitions are known to permit rigorous statistical discrimination of trend mechanisms based on these transitions alone. However, the mechanism can be investigated by using “minor transitions” in hierarchy, or, in other words, changes in the degree of individuation of the upper level. This study tests the null hypothesis that the probability (or rate) of increase and decrease in individuation are equal in a phylogenetic context. We found published phylogenetic trees for clades spanning minor transitions across the tree of life and identified changes in character states associated with those minor transitions. We then used both parsimony- and maximum-likelihood-based methods to test for asymmetrical rates of character evolution. Most analyses failed to reject equal rates of hierarchical increase and decrease. In fact, a bias toward decreasing complexity was observed for several clades. These results suggest that no strong tendency exists for hierarchical complexity to increase.
Current Oral Contraceptive Status and Periodontitis in Young Adults
Authors: Mullally Brian H. , Coulter Wilson A. , Hutchinson Julia D. , Clarke Heather A. 
Published: May 2007

Background: The aim of this study was to investigate the influence of current hormonal contraceptive medication on periodontal health in young females.Methods: Fifty women aged 20 to 35 years (mean ± SD: 29.7 ± 4.7 years) had a comprehensive periodontal examination. Current and previous contraceptive pill use was assessed by a questionnaire. Periodontal assessment included plaque index, gingival index, probing depth, and attachment level at six sites per tooth. The periodontal health of current pill users was compared to that of women not taking the pill.Results: Forty‐two percent of subjects were taking the contraceptive pill at the time of periodontal examination. Current pill users had deeper mean probing depths compared to non‐users (3.3 mm versus 2.7 mm; P = 0.006) and more severe attachment loss (2.6 mm versus 1.7 mm; P = 0.015). Pill users had more sites with bleeding on probing (44.0% versus 31.1%; P = 0.017).Conclusion: Current users of oral contraceptives had poorer periodontal health.
Effect of Platelet‐Rich Plasma on the Healing of Intrabony Defects Treated With an Anorganic Bovine Bone Mineral and Expanded Polytetrafluoroethylene Membranes
Authors: Döri Ferenc , Huszár Tamás , Nikolidakis Dimitris , Arweiler Nicole B. , Gera István , Sculean Anton 
Published: May 2007

Background: Regenerative periodontal therapy with a combination of platelet‐rich plasma (PRP) + an anorganic bovine bone mineral (ABBM) + guided tissue regeneration (GTR) has been shown to result in significantly higher probing depth reductions and clinical attachment level gains compared to treatment with open flap debridement (OFD) alone, ABBM alone, or GTR alone. However, there are no data evaluating to what extent the use of PRP may additionally enhance the clinical outcome of the therapy compared to treatment with ABBM + GTR. This study aimed to clinically evaluate the effect of PRP on the healing of deep intrabony defects treated with ABBM and GTR by means of a non‐resorbable expanded polytetrafluoroethylene (ePTFE) membrane.Methods: Twenty‐four patients with advanced chronic periodontal disease and displaying one intrabony defect were randomly treated with a combination of either PRP + ABBM + GTR or ABBM + GTR. The following clinical parameters were evaluated at baseline and at 1 year after treatment: plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), and clinical attachment level (CAL). The primary outcome variable was CAL.Results: No differences in any of the studied parameters were observed at baseline between the two groups. Healing was uneventful in all patients. At 1 year after therapy, the sites treated with PRP + ABBM + GTR showed a reduction in mean PD from 8.6 ± 1.7 mm to 3.1 ± 1.3 mm (P <0.001) and a change in mean CAL from 10.3 ± 1.4 mm to 5.7 ± 1.6 mm (P <0.001). In the group treated with ABBM + GTR, mean PD was reduced from 8.8 ± 1.7 mm to 3.1 ± 1.0 mm (P <0.001), and the mean CAL changed from 10.4 ± 2.6 mm to 5.9 ± 1.8 mm (P <0.001). In both groups, all sites gained ≥3 mm of CAL. CAL gains ≥4 mm were measured in 83% (i.e., in 10 of 12 defects) of the cases treated with PRP + ABBM + GTR and in 92% (i.e., in 11 of 12 defects) treated with ABBM + GTR. No statistically significant differences in any of the studied parameters were observed between the two groups at 1‐year reevaluation.Conclusion: Within its limits, the present study has shown that, at 1 year after regenerative therapy in periodontal intrabony defects, optimal clinical results were obtained with ABBM + GTR with a non‐resorbable barrier, with or without the addition of PRP.
Root Coverage in Isolated Gingival Recessions Using Autograft Versus Allograft: A Pilot Study
Authors: Joly Julio C. , Carvalho Alexandre M. , da Silva Robert C. , Ciotti Danilo L. , Cury Patricia R. 
Published: May 2007

Background: Different surgical techniques have been used to treat gingival recessions. This preliminary study compared clinical findings for the treatment of isolated gingival defects using a coronally positioned flap associated with a subepithelial connective tissue graft or an acellular dermal matrix graft.Methods: Ten subjects with bilateral and comparable Miller Class I or II defects were selected. The defects were ≥3.0 mm deep and were assigned randomly to the test group, which was treated with a coronally positioned flap associated with an acellular dermal matrix, or to the control group, which was treated with a coronally positioned flap associated with a subepithelial connective tissue graft. Probing depth (PD), clinical attachment level (CAL), gingival recession depth (GRD), and width (KT) and thickness (GT) of the keratinized tissue were assessed at baseline and 6 months after the surgery.Results: Mean root coverage was 50% in the test group (representing a gingival margin shift of 2.1 ± 0.99 mm) and 79.5% in the control group (representing a gingival margin shift of 3.5 ± 1.20 mm). These results were statistically different on intra‐ and intergroup comparisons (P <0.05). Between‐group comparisons revealed statistically significantly greater gains in CAL, GRD, and GT in the control group (P ≤0.05); no differences were found for PD or KT (P ≥0.05).Conclusions: The coronally positioned flap associated with a subepithelial connective tissue graft or an acellular dermal matrix graft was effective in root coverage. However, the coronally positioned flap associated with a connective tissue graft provided a more favorable clinical outcome. More expanded studies are needed to confirm the present findings.
Mechanical Stress Induces Osteopontin Expression in Human Periodontal Ligament Cells Through Rho Kinase
Authors: Wongkhantee Suchart , Yongchaitrakul Tussanee , Pavasant Prasit 
Published: May 2007

Background: Mechanical stress such as orthodontic forces can produce mechanical damage and inflammatory reaction in the periodontium. Osteopontin (OPN) is a multifunctional cytokine that has been correlated with periodontal disease progression. Because the periodontal ligament (PDL) can be affected by stress and PDL cells are involved in periodontal destruction and remodeling, we aimed to study the influence of mechanical stress on the expression and regulation of OPN in human PDL (HPDL) cells.Methods: The mechanical stress was generated by continuous compressive force, and the expression of OPN was examined by reverse transcription‐polymerase chain reaction and Western analysis. The application of inhibitors was used to examine the mechanism involved.Results: Both mRNA and protein expression of OPN significantly increased in a force‐dependent manner. Increase of receptor activator of nuclear factor‐kappa B ligand (RANKL) was also observed. Interestingly, application of indomethacin could abolish the induction of RANKL but not that of OPN, suggesting the cyclooxygenase‐independent mechanism for stress‐induced OPN expression. In addition, the upregulation of OPN was diminished by Rho kinase inhibitor but not by cytochalasin B.Conclusions: Mechanical stress affects OPN expression in HPDL cells through the Rho kinase pathway. Because OPN participates in bone resorption and remodeling induced by mechanical and biologic signals, these results suggest the significance of stress‐induced OPN in HPDL cells in alveolar bone resorption and remodeling.