bluuebunny/crossref_metadata_2025_split huggingface dataset:
Levels of Interferon‐Gamma and Transcription Factor T‐Bet in Progressive Periodontal Lesions in Patients With Chronic Periodontitis
Authors: Dutzan Nicolas , Vernal Rolando , Hernandez Marcela , Dezerega Andrea , Rivera Oriana , Silva Nora , Aguillon Juan Carlos , Puente Javier , Pozo Patricia , Gamonal Jorge 
Published: February 2009

Background: Periodontitis is an infection with an episodic pattern of tissue‐support destruction. During the generation of a primary CD4+ T helper 1 (Th1) response, interferon‐gamma (IFN‐γ) acts as a positive regulator by selectively inducing Th1 differentiation through increased transcription of T‐bet. The aims of this work were to determine IFN‐γ levels in samples of gingival crevicular fluid (GCF) and to determine IFN‐γ and transcription factor T‐bet expression in gingival tissue from patients undergoing the progression of chronic periodontitis.Methods: One hundred six patients with moderate or advanced chronic periodontitis were selected. Periodontitis was characterized by at least six sites with probing depth ≥5 mm, clinical attachment loss ≥3 mm, and radiographic bone loss. Periodontitis progression was determined by the tolerance method. GCF was collected using a paper strip, and enzyme‐linked immunosorbent assay was performed to determine the total amount of IFN‐γ. Gingival biopsies were obtained from patients for real‐time reverse transcription‐polymerase chain reaction to determine IFN‐γ and T‐bet expression. Statistical analysis was performed using statistical software. Data were expressed as subject means ± SD. The χ2 and Student t tests were used.Results: The total amount and concentration of cytokine IFN‐γ were significantly higher in active sites than in inactive sites (99.90 versus 68.90 pg; P = 0.03; 106.62 pg/mg versus 75.64 pg/mg, P = 0.04, respectively). Active sites showed a significantly lower Δ cycle threshold (Ct) of IFN‐γ than inactive sites (P = 0.04), whereas the expression of transcription factor T‐bet was increased 1.42‐fold in active sites compared to inactive sites.Conclusion: The total amount and concentration of cytokine IFN‐γ in GCF samples and transcription factor T‐bet expression were increased in progressive periodontal lesions in patients with chronic periodontitis.
The Role of Bone Decortication in Enhancing the Results of Guided Bone Regeneration: A Literature Review
Authors: Greenstein G. , Greenstein B. , Cavallaro J. , Tarnow D. 
Published: February 2009

Background: Bone decortication is often performed as part of a guided bone regeneration (GBR) procedure. The biologic rationale for decortication of bone is to allow progenitor cells easy access to a GBR‐treated site and to facilitate prompt angiogenesis. It also may enhance the physical connection between a bone graft and a recipient site. However, the concept of decortication prior to a GBR procedure is controversial because there are no human clinical trials to support its effectiveness, and there are opposing points of view derived from animal studies regarding its usefulness.Methods: The literature was assessed to determine whether there are enough data to validate the rationale for using decortication of bone as an integral part of GBR procedures. Eight searches were performed seeking controlled clinical trials that addressed the ability of decortication to enhance GBR.Results: Three controlled animal clinical trials were found that supported the use of decortication prior to performing GBR. Two controlled animal clinical trials were located that indicated decortication did not improve GBR procedures. No human controlled clinical trial was identified that addressed the ability of decortication to alter GBR procedures. The literature addressing the capacity of decortication to affect onlay grafting or wound healing also provided mixed results.Conclusion: There is conflicting information and not enough clinical trials to make a definitive determination as to the merits of bone decortication prior to GBR procedures.
Periodontitis Severity Plus Risk as a Tooth Loss Predictor
Authors: Martin John A. , Page Roy C. , Kaye Elizabeth Krall , Hamed Mohamed T. , Loeb Carl F. 
Published: February 2009

Background: Tooth loss can be a consequence of the natural history of periodontitis. Stratification of periodontitis severity, risk, and tooth loss exists within the United States adult population, and tooth loss correlates to severity and risk. We evaluated the loss of teeth for a periodontitis‐affected population categorized by the combination of severity and risk in which the subjects predominantly did not receive periodontal treatment.Methods: The clinical records of 523 subjects enrolled in the Veterans Affairs Dental Longitudinal Study, covering a period of 15 years, were used. Disease severity, risk level, and the number of teeth lost for each subject were determined.Results: A stepwise regression analysis showed that disease and risk scores predicted mean tooth loss rate. The P value for the disease score was <0.0005, and the P value for the risk score was 0.001. The ordinal logistic regression model showed that disease (P = 0.002) and risk scores (P = 0.000) were significantly associated with the probability of subjects losing a specific number of teeth.Conclusions: Tooth loss is more precisely and accurately predicted by the combination of risk score and periodontal disease score than by either score alone. The combined scores may be a surrogate variable for periodontal status. Because the scores are derived from routine clinical measurements, they may be useful for population surveillance and dynamics, practice management, patient care decisions, practice‐based research, and the determination of treatment effectiveness and the factors required for successful treatment, resulting in improved oral health and higher clinician productivity and income.
Levels of Serum Interleukin (IL)‐6 and Gingival Crevicular Fluid of IL‐1β and Prostaglandin E2 Among Non‐Smoking Subjects With Gingivitis and Type 2 Diabetes
Authors: Andriankaja O.M. , Barros S.P. , Moss K. , Panagakos F.S. , DeVizio W. , Beck J. , Offenbacher S. 
Published: February 2009

Background: The goal of this study was to assess whether non‐smoking patients with type 2 diabetes present with increased levels of local and systemic proinflammatory mediators and, if so, whether such an increase is associated with enhanced clinical gingival inflammation compared to non‐smoking patients without diabetes.Methods: We used a cross‐sectional database consisting of 725 self‐reported lifelong non‐smokers aged 53 to 74 years. Gingival crevicular fluid (GCF) levels of interleukin (IL)‐1β and prostaglandin E2 (PGE2) and serum levels of IL‐6 were measured using enzyme‐linked immunosorbent assay. No participant had probing depth >3 mm. Participants with bleeding on probing (BOP) in <10% of sites were classified as healthy, whereas those with BOP in ≥10% of sites were defined as having biofilm–gingival interface (BGI) gingivitis.Results: Approximately 53% (n = 385) and 11% (n = 80) of the sample had BGI gingivitis and type 2 diabetes, respectively. The mean age‐adjusted level of GCF IL‐1β was significantly elevated in the diabetic group compared to the non‐diabetic group (P = 0.048), but serum IL‐6 (P = 0.14) and GCF PGE2 were not (P = 0.98). The mean GCF IL‐1β and PGE2 levels were significantly elevated in subjects with BGI gingivitis (136.2 ± 112.9 ng/ml and 277.2 ± 187.2 ng/ml, respectively) compared to subjects with gingival health (95.9 ± 82.9 ng/ml and 205.7 ± 149.6 ng/ml, respectively), regardless of diabetic status (P <0.001 for both). However, serum IL‐6 was elevated in subjects with BGI gingivitis compared to subjects with gingival health only among subjects with diabetes (2.9 ± 3.2 pg/ml versus 1.5 ± 1.4 pg/ml; P = 0.008). With the exception of serum IL‐6 in subjects without diabetes, an increase in the levels of proinflammatory mediators was associated with increased odds of having BGI gingivitis. The associations were stronger in the diabetic group.Conclusions: Type 2 diabetes may increase the host inflammatory response to oral biofilm, which, in turn, may exacerbate preconditions associated with gingivitis in susceptible individuals. Furthermore, systemic inflammation, as demonstrated by the increased level of serum IL‐6, is associated with BGI gingivitis among non‐smoking patients with diabetes.
Identification of N‐Methyl‐D‐Aspartate Receptor Subunit in Human Periodontal Ligament Fibroblasts: Potential Role in Regulating Differentiation
Authors: Yu Ji‐Hee , Lee Seung‐Pyo , Kim Tae‐Il , Jang Jun‐Hyeog 
Published: February 2009

Background: Periodontal ligament fibroblasts (PDLFs), which can be differentiated into osteoblasts, are crucial cells for the regeneration of the periodontal tissue. Although N‐methyl‐D‐aspartate (NMDA) receptors were reported to be involved in bone formation by affecting osteoblasts, the existence and function of NMDA receptors in PDLFs have not been confirmed. The purpose of this study was to examine the expression of NMDA receptors and their role in human PDLFs.Methods: Human PDLFs were cultured and evaluated to identify the subunits of NMDA receptors (NR) by reverse transcription‐polymerase chain reaction, Western blot analysis, and immunocytochemistry. Then, the cells were assigned to four different groups: a control media group, a control media with NMDA receptor antagonist group, a differentiation media group, and a differentiation media with NMDA receptor antagonist group. Cell proliferation assay, alkaline phosphatase (ALP) activity analysis, and mineralization assay were performed to determine whether NMDA receptors affected the function of PDLFs.Results: NR1, NR2B, and NR2D were detected in human PDLFs. There was no statistically significant difference in proliferation among the groups. However, the NMDA receptor antagonist–treated group showed a significant reduction in ALP activity (P <0.05). Moreover, the NMDA receptor antagonist–supplemented group presented no mineralization.Conclusions: This study revealed the existence of NMDA receptors in human PDLFs and specified their subunits. Moreover, NMDA receptors had a significant influence on the differentiation and mineralization of human PDLFs but did not affect their proliferation. These results suggest that NMDA receptors may play an important role in the differentiation and mineral tissue formation of human PDLFs.
Effects of Ascorbic Acid on Gingival Melanin Pigmentation In Vitro and In Vivo
Authors: Shimada Yasuko , Tai Hideaki , Tanaka Aya , Ikezawa‐Suzuki Ikuyo , Takagi Keiji , Yoshida Yasuhiro , Yoshie Hiromasa 
Published: February 2009

Background: Gingival melanin pigmentation may cause esthetic concerns, even if no serious medical problem is present. As an inhibitor of melanin formation, ascorbic acid is often used to treat skin melanin pigmentation. Thus, the present study investigated the effects of ascorbic acid on gingival melanin pigmentation in vitro and in vivo.Methods: The effects of ascorbic acid on melanin formation were evaluated in vitro in B16 mouse melanoma cells and three‐dimensional human skin models. In addition, a clinical trial was performed to investigate the inhibitory effects of a gel containing ascorbic acid 2‐glucoside (AS‐G gel) on gingival melanin pigmentation. This study used a double‐masked, split‐mouth design on 73 subjects with symmetric gingival melanin pigmentation. AS‐G gel was applied to one side of the gingiva for 12 weeks, whereas placebo gel was applied to the other side as a control. Luminance (L∗)‐value, which describes the lightness of gingiva, was determined by spectrophotometry to obtain an objective measure of melanin pigmentation every 4 weeks.Results: Ascorbic acid significantly inhibited tyrosinase activity and melanin formation in B16 mouse melanoma cells (P <0.01 and P <0.05, respectively). The inhibitory effects of ascorbic acid on melanin formation were also significant in three‐dimensional human skin models (P <0.01). Moreover, in the clinical trial, a significant relative change in pigmentation was seen after 4 weeks with the application of AS‐G gel compared to placebo (L∗‐value ratio).Conclusion: Ascorbic acid (AS‐G) has potential for the treatment of gingival melanin pigmentation.
Changes in Inflammatory Mediators in Peri‐Implant Fluid After Implant Insertion
Authors: Venza Mario , Visalli Maria , Lo Giudice Giuseppe , Cicciù Marco , Passi Pietro , Teti Diana 
Published: February 2009

Background: Endosseous dental titanium implants have revolutionized restorative dentistry and have made a significant impact on improved patient care. The aim of this study was to compare and evaluate the influence of the placement technique on periodontal health.Methods: A baseline examination was performed in patients with submerged and non‐submerged titanium implants, including an evaluation of plaque index (PI), gingival index (GI), periodontal probing depth (PD), clinical attachment level (CAL), and bone level, as well as histamine and arachidonic acid metabolite concentrations, in the peri‐implant crevicular fluid. Examinations were repeated after 12, 24, and 36 months.Results: Bone loss was significantly higher in the submerged group relative to the non‐submerged group at 3 years (P <0.01), with a slight increase at 24 months. All clinical parameters were significantly higher in the submerged group relative to the non‐submerged group at 24 and 36 months (P <0.05 for PI; P <0.01 for GI, PD, and CAL). The mean levels of histamine and other inflammatory mediators were significantly higher, whereas 15(S)‐hydroxy‐5,8,11,13‐eicosatetraenoic acid concentrations were significantly reduced in the submerged group, with a high correlation with periodontal indices at 24 and 36 months (P <0.001).Conclusion: This longitudinal study suggested that submerged implants present a number of risks for periodontal complications compared to non‐submerged implants, which can be evidenced by inflammatory mediator variations in the peri‐implant crevicular fluid.
Single‐Flap Approach With Buccal Access in Periodontal Reconstructive Procedures
Authors: Trombelli Leonardo , Farina Roberto , Franceschetti Giovanni , Calura Giorgio 
Published: February 2009

Background: New surgical techniques have been developed to optimize primary closure as well as to minimize the surgical trauma in the reconstructive procedures of periodontal intraosseous defects. Recently, we proposed a minimally invasive procedure, the single‐flap approach (SFA), specifically indicated when the defect extension is prevalent on the buccal or oral side. The basic principle of the SFA is the elevation of a flap to access the defect only on one side (buccal or oral), leaving the opposite side intact. The present case series reports preliminary data on the clinical effectiveness of SFA with buccal access in conjunction with a collagen membrane and a hydroxyapatite (HA)‐based biomaterial in the reconstructive treatment of deep periodontal intraosseous defects.Methods: Ten intraosseous defects in 10 patients were accessed with a buccal SFA and treated with a collagen membrane and an HA‐based graft biomaterial. The follow‐up period following the regenerative procedure ranged from 6 to 14 months (mean: 10.0 ± 3.0 months).Results: Clinical attachment level (CAL) decreased from 11.2 ± 2.6 mm presurgery to 6.4 ± 1.9 mm post‐surgery. Probing depth was 9.0 ± 2.8 mm before surgery and 3.8 ± 1.5 mm post‐surgery. Gingival recession increased from 2.2 ± 1.9 mm presurgery to 2.6 ± 1.3 mm post‐surgery.Conclusions: Challenging intraosseous defects, surgically accessed with a buccal SFA and treated with a combined graft/guided tissue regeneration technique, may heal with a substantial CAL gain. Limited postsurgical recession indicates that SFA may represent a suitable option to surgically treat defects in areas with high esthetic demands.
Revisiting the potential for benefit sharing in the management of trans-boundary rivers
Authors: Dombrowsky Ines 
Published: February 2009

It has been suggested that trans-boundary water conflicts may be resolved through benefit sharing. The idea of benefit sharing is that a zero-sum game of water sharing is replaced through a positive-sum game of benefit sharing. In order to test the benefit sharing hypothesis, this paper presents a conceptual analysis of the incentives and institutional prerequisites required to realize mutual benefits in the use of trans-boundary rivers.
The paper argues that it is useful to distinguish negative and positive unidirectional externality problems related to the use of trans-boundary rivers, as these two cases represent fundamentally different cooperation problems. In the case of negative externalities, the benefits of cooperation exist in principle, but their realization requires an agreement on often disputed property rights as well as on the set up of an enforcement mechanism. Thus cooperation remains institutionally demanding. In contrast, in the case of positive externality problems, no property rights issues are involved. However, whether cooperation can be expected depends on the underlying payoff structure. The downstream riparian can be expected to participate in the provision of a positive externality upstream, either if the project is only collectively rational (coordination problem) or if the downstream riparian's participation allows for a Pareto improvement vis-à-vis the non-cooperative solution (cooperation problem). Given the property rights implications of negative externality problems, it may be useful, where possible, to refocus from negative to positive externality problems.
Water policy impact assessment – combining modelling techniques in the Great Barrier Reef region
Authors: Smajgl A. , Morris S. , Heckbert S. 
Published: February 2009

The Reef Water Quality Protection Plan (Reef Plan) defined a landmark for policy in the Great Barrier Reef (GBR) region. It identifies actions, mechanisms and partnerships and builds on existing government policies, industry and community initiatives for the purpose of “halting and reversing the decline in water quality entering the Reef within 10 years” through “reducing the load of pollutants from diffuse sources in the water entering the Reef”. A range of different indicators proposed for the nine strategies of the plan define policy goals that require an integrated assessment of the Great Barrier Reef region.
In this context and under given uncertainties in regard to policy outcomes, decision support systems can help simulate the impact of potential policy options. Policy options involving water quantity and water quality questions and the underlying context of land use require an understanding of environmental, economic and social consequences.
This paper presents an approach developed for the GBR region, which employs a computable general equilibrium (CGE) model and an agent-based model (ABM) for integrated policy impact assessment. This applied modelling approach shows that strengths of different modelling techniques can be combined to support water policy decision making more effectively. This paper is focused on integration in the form of policy process and research response regarding model design on two system scales that provide cross scale decision support.
Gas chromatography–mass spectrometry assay for determination of Nτ-methylhistamine concentration in canine urine specimens and fecal extracts
Authors: Ruaux Craig G. , Wright Jeannie M. , Steiner Jörg M. , Williams David A. 
Published: February 2009

Abstract
Objective—To develop and validate a gas chromatography–mass spectrometry (GC-MS) method for determination of Nτ-methylhistamine (NMH) concentration in canine urine and fecal extracts and to assess urinary NMH concentrations in dogs with mast cell neoplasia and fecal NMH concentrations in dogs with protein-losing enteropathy.
Sample Population—Urine specimens were collected from 6 healthy dogs and 7 dogs with mast cell neoplasia. Fecal extracts were obtained from fecal specimens of 28 dogs with various severities of protein-losing enteropathy, as indicated by fecal concentration of α1-proteinase inhibitor.
Procedures—NMH was extracted directly from urine, and fecal specimens were first extracted into 5 volumes of PBSS containing 1% newborn calf serum. Nτ-methylhistamine in specimens was quantified via stable isotope dilution GC-MS. The assay was validated via determination of percentage recovery of known amounts of NMH and interassay coefficients of variation. Urinary excretion of NMH was evaluated by means of NMH-to-creatinine concentration ratios.
Results—Recovery of NMH in urine and fecal extracts averaged 104.6% and 104.5%, respectively. Interassay coefficients of variation ranged from 5.4% to 11.7% in urine and 12.6% to 18.1% in fecal extracts. Urinary NMH excretion was significantly increased in dogs with mast cell neoplasia, compared with that in healthy dogs. No correlation was detected between severity of protein-losing enteropathy and fecal NMH concentration.
Conclusions and Clinical Relevance—This method provided a sensitive, reproducible means of measuring NMH in canine urine and fecal extracts. High urinary NMH-to-creatinine concentration ratios in dogs with mast cell neoplasia are consistent with increased histamine release in this disease.
Evaluation of polysulfated glycosaminoglycan or sodium hyaluronan administered intra-articularly for treatment of horses with experimentally induced osteoarthritis
Authors: Frisbie David D. , Kawcak Chris E. , McIlwraith C. Wayne , Werpy Natasha M. 
Published: February 2009

Abstract
Objective—To assess clinical, biochemical, and histologic effects of polysulfated glycosaminoglycan (PSGAG) or sodium hyaluronan administered intra-articularly in treatment of horses with experimentally induced osteoarthritis.
Animals—24 horses.
Procedures—Osteoarthritis was induced arthroscopically in 1 middle carpal joint of all horses. Eight horses received hyaluronan (20 mg) and amikacin (125 mg) intra-articularly on study days 14, 21, and 28. Eight horses received PSGAG (250 mg) and amikacin (125 mg) intra-articularly on study days 14, 21, and 28. Eight control horses received 2 mL of saline (0.9% NaCl) solution and amikacin (125 mg) intra-articularly on study days 14, 21, and 28. Clinical, radiographic, synovial fluid analysis, gross, histologic, histochemical, and biochemical findings were evaluated.
Results—No adverse treatment-related events were detected. Induced osteoarthritis caused a substantial change in lameness, response to flexion, joint effusion, and radiographic findings, and of these, synovial fluid effusion was reduced with PSGAG, compared with control horses. No changes in clinical signs were seen with PSGAG or hyaluronan, compared with control horses. Histologically, the degree of synovial membrane vascularity and subintimal fibrosis was significantly reduced with PSGAG treatment, compared with controls. Histologically, significantly less fibrillation was seen with hyaluronan treatment, compared with controls.
Conclusions and Clinical Relevance—Results indicated that PSGAG and hyaluronan had beneficial disease-modifying effects and are viable therapeutic options for osteoarthritis in horses.