bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of the capsular polysaccharide biosynthesis locus of Porphyromonas gingivalis and development of a K1‐specific polymerase chain reaction‐based serotyping assay
Authors: Brunner J. , Crielaard W. , Van Winkelhoff A. J. 
Published: July 2008

Background and Objective:  Porphyromonas gingivalis is a gram‐negative obligate anaerobe that is strongly associated with severe periodontitis. Previous reports showed an association of P.  gingivalis capsular polysaccharide with virulence. The K1 capsular polysaccharide was found to be more immunostimulatory than the other serotypes. Our objective was to explore the genetic background of the capsule biosynthesis (K‐antigen) locus in a representative group of K1 serotype strains.Material and Methods:  We used restriction fragment length polymorphism, polymerase chain reaction (PCR) and DNA sequencing to study the capsular polysaccharide locus in P. gingivalis K1 strains. For serotyping by double immunodiffusion and PCR we used 32 strains of P. gingivalis, including strains of all six known K serotypes.Results:  All tested K1 strains showed high conservation of the capsular polysaccharide locus, although a DNA re‐arrangement was found in two strains. Based on this information a K1‐specific PCR‐based serotyping assay was designed. The specificity and sensitivity of this test were confirmed using non‐K1 P. gingivalis serotypes.Conclusion:  The capsular polysaccharide locus of P. gingivalis is conserved but may vary slightly among K1 strains. The new K1 serotyping assay presented here is much faster than double immunodiffusion and can detect K1 strains in a very selective and sensitive way. This method may therefore be clinically relevant in the detection of the virulent P. gingivalis K1 serotype.
Interleukin‐4, a T‐helper 2 cell cytokine, is associated with the remission of periodontal disease
Authors: Pradeep A. R. , Roopa Y. , Swati P. P. 
Published: July 2008

Background and Objectives:  Interleukin‐4 (IL‐4), secreted mainly by T‐helper 2 cells, is a key cytokine for the growth and proliferation of B lymphocytes. Previous studies have proved that IL‐4 has an anti‐inflammatory effect owing to its efficient inhibition of the production of proinflammatory cytokines such as tumour necrosis factor‐α (TNF‐α), IL‐1α, IL‐1β, IL‐6 and IL‐8 by monocytes/macrophages. The aim of the present study was to assess the relation between clinical parameters and concentrations of IL‐4 within gingival crevicular fluid from inflamed gingiva and periodontitis sites and, subsequently, after treatment of the periodontitis sites.Material and Methods:  A total of 60 subjects were divided into three groups based on gingival index (GI), pocket probing depth and clinical attachment loss (CAL): healthy (group 1), gingivitis (group 2) and chronic periodontitis (group 3). A fourth group (group 4) consisted of 20 subjects from group 3, 6–8 weeks after treatment (i.e. scaling and root planing). Gingival crevicular fluid samples collected from each patient were quantified for IL‐4 using the enzymatic immunometric assay.Results:  The highest mean concentration of IL‐4 was obtained for group 1 (99.39 ± 49.33 pg/mL) and the lowest mean concentration of IL‐4 was obtained for group 3 (15.78 ± 21.92 pg/mL). The mean IL‐4 concentrations for group 2 (64.34 ± 39.56 pg/mL) and group 4 (68.92 ± 42.85 pg/mL) were intermediate between the levels in healthy subjects and periodontitis subjects.Conclusion:  The mean concentration of IL‐4 decreased from periodontal health to disease. Thus, we suggest that type 2 helper T cell cytokine, as represented by IL‐4, was associated with the remission or improvement of periodontal disease.
CXCL13 expression and follicular dendritic cells in relation to B‐cell infiltration in periodontal disease tissues
Authors: Nakajima T. , Amanuma R. , Ueki‐Maruyama K. , Oda T. , Honda T. , Ito H. , Yamazaki K. 
Published: July 2008

Background and Objective:  B lymphocyte is the dominant infiltrating cell type in periodontitis lesions. CXCL13, produced by follicular dendritic cells, endothelial cells and fibroblasts, is crucial for B‐cell trafficking. An association between chronic inflammation and lymphoid organogenesis has been reported in infection and in autoimmune responses, in which T‐cell/B‐cell follicles with a follicular dendritic cell network are formed. The aim of this study was to examine CXCL13 expression and follicular dendritic cell distribution in relation to B‐cell infiltration in chronic inflammatory periodontal lesions.Material and Methods:  Fifty‐eight gingival tissue biopsies from patients with periodontitis and 25 samples from subjects with gingivitis were analyzed. Gene expression for CXCL13 and for the CD21 long isoform was analyzed using the reverse transcription–polymerase chain reaction. Immunohistochemical analysis was performed using antibodies to CXCL13, CXCR5, follicular dendritic cells, CD3 and CD19 on serial cryostat sections.Results:  mRNA for CXCL13 was expressed in both periodontitis and gingivitis tissues. The number of CXCL13+ cells was significantly higher in periodontitis than in gingivitis in connective tissues subjacent to the pocket epithelium and positively correlated with the number of CD19+ cells. CXCL13+ cells were distributed in B‐cell‐dominant areas both with and without follicular dendritic cells. Although obvious reticular networks of follicular dendritic cells were not found in periodontitis and gingivitis, the accumulation of follicular dendritic cells in B‐cell‐dominant areas in periodontitis was observed in some patients.Conclusion:  These findings suggested that CXCL13 and follicular dendritic cells were involved in B‐cell recruitment to, and B‐cell distribution in, chronic inflammatory periodontal lesions.
T cells are able to promote lipopolysaccharide‐induced bone resorption in mice in the absence of B cells
Authors: Yamaguchi M. , Ukai T. , Kaneko T. , Yoshinaga M. , Yokoyama M. , Ozaki Y. , Hara Y. 
Published: July 2008

Background and Objective:  T cells and their cytokines are believed to be key factors in periodontal disease and bone resorption. We previously showed that T cells transferred to nude mice were related to inflammatory bone resorption in vivo. However, it has not been clarified whether T cells can induce bone resorption in the absence of B cells. In this study, we therefore investigated the ability of T cells to induce bone resorption without B cells, using both T cell‐ and B cell‐deficient mice with severe combined immune deficiency (SCID).Material and Methods:  Escherichia coli lipopolysaccharide (LPS) was injected into the gingivae of SCID mice reconstituted by T cells (SCID + T mice). Wild‐type C.B‐17 mice and SCID mice were used as control animals. Alveolar bone resorption and production of cytokines in the gingivae were then compared histopathologically and immunohistologically.Results:  The degree of bone resorption in SCID + T mice was significantly greater than that in SCID mice but less than that in wild‐type mice. The same tendency was found for expression of receptor activator of nuclear factor κB ligand. The number of interferon‐γ‐positive cells in SCID + T mice was the highest of the three groups. In contrast, interleukin‐4‐positive cells were detected in wild‐type mice but not in SCID + T and SCID mice.Conclusion:  The results suggest that T cells are able to promote LPS‐induced bone resorption in the absence of B cells. The expressions of cytokines in the presence of B cells are quite different.
Subculture affects the phenotypic expression of human periodontal ligament cells and their response to fibroblast growth factor‐2 and bone morphogenetic protein‐7 in vitro
Authors: Lossdörfer S. , Fiekens D. , Salik M. I. , Götz W. , Jäger A. 
Published: July 2008

Background and Objective:  Although periodontal ligament cells display several osteoblastic traits, their phenotypic expression is still not well established. It remains a matter of debate whether they resemble a terminally differentiated cell type or an intermediate maturation state that potentially can be directed towards a fibroblastic or an osteoblastic phenotype.Material and Methods:  To explore the characteristics of periodontal ligament cells in greater detail, fourth‐passage, sixth‐passage and eighth‐passage human periodontal ligament cells were cultured for up to 3 wk. Ki‐67, alkaline phosphatase, osteocalcin, osteoprotegerin and receptor activator of nuclear factor‐κB ligand (RANKL) mRNA expression was quantified by real‐time polymerase chain reaction. Furthermore, the cellular response to fibroblast growth factor‐2 and bone morphogenetic protein‐7 was examined in first‐passage and fourth‐passage cells. Dermal fibroblasts (1BR.3.G) and osteoblast‐like cells (MG63) served as reference cell lines.Results:  Proliferation decreased over time and was highest in fourth‐passage cells. The expression of differentiation parameters, osteoprotegerin and RANKL increased with culture time and was higher in fourth‐passage cells than in cells of later passages. The RANKL/osteoprotegerin ratio increased steadily until day 21. Administration of fibroblast growth factor‐2 enhanced cell numbers in both passages, whereas alkaline phosphatase and osteocalcin production remained unchanged. By contrast, exposure of periodontal ligament cells to bone morphogenetic protein‐7 resulted in a reduction of cell number in the first and fourth passages, whereas the production of alkaline phosphatase and osteocalcin was enhanced. In dermal fibroblasts, differentiation parameters did not respond to both stimuli. MG63 cells behaved similarly to periodontal ligament cells.Conclusion:  These results indicate that subculture affects the phenotypic expression of human periodontal ligament cells with respect to the characteristics that these cells share with osteoblasts. Furthermore, the periodontal ligament cell phenotype can be altered by fibroblastic and osteoblastic growth factors.
Analysis of the association of polymorphism in the osteoprotegerin gene with susceptibility to chronic kidney disease and periodontitis
Authors: Baioni C. S. , De Souza C. M. , Ribeiro Braosi A. P. , Luczyszyn S. M. , Dias da Silva M. A. , Ignácio S. A. , Naval Machado M. Â. , Benato Martins W. D. , Riella M. C. , Pecoits‐Filho R. , Trevilatto P. C. 
Published: July 2008

Background and Objective:  Chronic kidney disease (CKD) is a complex disorder, which results in several complications involving disturbance of mineral metabolism. Periodontal disease is an infectious disease that appears to be an important cause of systemic inflammation in CKD patients. Periodontal disease is characterized by clinical attachment loss (CAL) caused by alveolar bone resorption around teeth, which may lead to tooth loss. Osteoprotegerin (OPG) is a key regulator of osteoclastogenesis. Polymorphisms are the main source of genetic variation, and single nucleotide polymorphisms (SNPs) have been reported as major modulators of disease susceptibility. The aim of this study was to investigate the association of a polymorphism located at position –223 in the untranslated region of the OPG gene, previously known as –950, with susceptibility to CKD and periodontal disease.Material and Methods:  A sample of 224 subjects without and with CKD (in hemodialysis) was divided into groups with and without periodontal disease. The OPG polymorphism was analyzed by polymerase chain reaction and restriction fragment length polymorphism.Results:  No association was found between the studied OPG polymorphism and susceptibility to CKD or periodontal disease.Conclusion:  It was concluded that polymorphism OPG–223 (C/T) was not associated with CKD and periodontal disease in a Brazilian population. Studies on other polymorphisms in this and other genes of the host response could help to clarify the involvement of bone metabolism mediators in the susceptibility to CKD and periodontal disease.
Expression of metalloproteinases and their tissue inhibitors in inflamed gingival biopsies
Authors: Gonçalves L. D. R. , Oliveira G. , Hurtado P. A. , Feitosa A. , Takiya C. M. , Granjeiro J. M. , Trackman P. C. , Otazú I. , Feres‐Filho E. J. 
Published: July 2008

Objectives:  Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) are known to be involved in the periodontal disease process. Results of in vivo MMPs and TIMPs gene expressions in the gingiva, though, are still controversial. In the present study, we compared the gene expression of MMP‐1, ‐2, ‐9, ‐13 and TIMP‐1, ‐2 in healthy and inflamed gingiva.Methods:  38 gingival samples were collected from gingivitis (n = 10), advanced chronic periodontitis (n = 10), generalized aggressive periodontitis (n = 8) and periodontally healthy individuals (n = 10). Total RNA isolated from those samples was subjected to reverse transcription followed by amplification by polymerase chain reaction (RT‐PCR). Products were visualized in agarose gels and quantified by optical densitometry. Samples were also processed for gelatin zymography and Western blotting for MMP‐2 and MMP‐9 in order to assess for post‐transcriptional MMP regulation at the protein level.Results:  The frequencies and levels of transcripts encoding MMPs and TIMPs were found to be not significantly different among groups (p > 0.05, Fisher’s Exact and Kruskall‐Wallis tests). There is a trend towards higher MMP‐2 and ‐9 gelatinase activities in the inflamed samples, although not statistically significant. In contrast, zymography and Western blotting studies show that MMP‐2 is virtually absent in the chronic periodontitis group.Conclusion:  These results could reflect a complex regulation of MMPs and TIMPs’ gene expression in the course of gingival inflammation. They also reveal a great biological diversity even among individuals with similar periodontal status.
Apical tooth germ cell‐conditioned medium enhances the differentiation of periodontal ligament stem cells into cementum/periodontal ligament‐like tissues
Authors: Yang Z‐H. , Zhang X‐J. , Dang N‐N. , Ma Z‐F. , Xu L. , Wu J‐J. , Sun Y‐J. , Duan Y‐Z. , Lin Z , Jin Y. 
Published: July 2008

Background and Objective:  Limitations of current periodontal regeneration modalities in both predictability and extent of healing response, especially on new cementum and attachment formation, underscore the importance of restoring or providing a microenvironment that is capable of promoting the differentiatiation of periodontal ligament stem cells (PDLSCs) towards cementoblast‐like cells and the formation of cementum/periodontal ligament‐like tissues. The aim of this study was to investigate the biological effect of conditioned medium from developing apical tooth germ cells (APTG‐CM) on the differentiation and cementogenesis of PDLSCs both in vitro and in vivo.Material and Methods:  Using the limiting dilution technique, single‐colony‐derived human PDLSCs were isolated and expanded to obtain homogeneous populations of PDLSCs. Morphological appearance, cell cycle analysis, bromodeoxyuridine incorporation, alkaline phosphatase (ALP) activity, mineralization behavior, gene expression of cementoblast phenotype and in vivo differentiation capacities of PDLSCs co‐cultured with APTG‐CM were evaluated.Results:  The induced PDLSCs exhibited several characteristics of cementoblast lineages, as indicated by the morphological changes, increased proliferation, high ALP activity, and the expression of cementum‐related genes and calcified nodule formation in vitro. When transplanted into immunocompromised mice, the induced PDLSCs showed tissue‐regenerative capacity to produce cementum/periodontal ligament‐like structures, characterized by a layer of cementum‐like mineralized tissues and associated periodontal ligament‐like collagen fibers connecting with the newly formed cementum‐like deposits, whereas control, untreated PDLSCs transplants mainly formed connective tissues.Conclusion:  Our findings suggest that APTG‐CM is able to provide a cementogenic microenvironment and induce differentiation of PDLSCs along the cementoblastic lineage. This has important implications for periodontal engineering.
Synchronous Ca2+ oscillation emerges from voltage fluctuations of Ca2+ stores
Authors: Yamashita Masayuki 
Published: July 2008

Synchronous Ca2+ oscillation occurs in various cell types to regulate cellular functions. However, the mechanism for synchronization of Ca2+ increases between cells remains unclear. Recently, synchronous oscillatory changes in the membrane potential of internal Ca2+ stores were recorded using an organelle‐specific voltage‐sensitive dye [Yamashita et al. (2006) FEBS J273, 3585–3597], and an electrical coupling model of the synchronization of store potentials and Ca2+ releases has been proposed [Yamashita (2006) FEBS Lett580, 4979–4983]. This model is based on capacitative coupling, by which transient voltage changes can be synchronized, but oscillatory slow potentials cannot be communicated. Another candidate mechanism is synchronization of action potentials and ensuing Ca2+ influx through voltage‐dependent Ca channels. The present study addresses the question of whether Ca2+ increases are synchronized by action potentials, and how oscillatory store potentials are synchronized across the cells. Electrophysiological and Ca2+‐sensitive fluorescence measurements in early embryonic chick retina showed that synchronous Ca2+ oscillation was caused by releases of Ca2+ from Ca2+ stores without any evidence of action potentials in retinal neuroepithelial cells or newborn neurons. High‐speed fluorescence measurement of store membrane potential surprisingly revealed that the synchronous oscillatory changes in the store potential were periodic repeats of a burst of high‐frequency voltage fluctuations. The burst coincided with a Ca2+ increase. The present study suggests that synchronization of Ca2+ release is mediated by the high‐frequency fluctuation in the store potential. Close apposition of the store membrane and plasma membrane in an epithelial structure would allow capacitative coupling across the cells.
EP4and EP2Receptor Subtypes Involved in Colonic Secretion in Rat
Authors: Mosa Ahmed Soliman , Hansen Mark Berner , Tilotta Cristina Maria , Bindslev Niels 
Published: July 2008

Abstract: The study was designed to determine the prostaglandin EP receptor subtypes functionally involved in electrogenic ion secretion in rat colon. With 30 rats, measurements of short circuit current (SCC) and slope conductance were obtained by Ussing chamber technique. Prostaglandin E2 (PGE2) and other EP receptor selective agonists were employed on stripped rat colon pre‐treated with indomethacin and theophylline. Receptor‐specific agonists were butaprost (EP2), sulprostone (EP1and EP3) and PGE1alcohol (OH‐PGE1) (EP4). GW627368X was used as a specific EP4receptor antagonist. Forskolin‐induced SCC was used as a control of tissue viability. The mean basal SCC was 24.5 ± 0.9 µA/cm2(range 9.8–45.1), and mean basal slope conductance was 23.7 ± 6.1 mS/cm2(range 9.7–39.8). The basal SCC decreased after pre‐treatment with indomethacin and increased after pre‐treatment with theophylline. PGE2, butaprost and OH‐PGE1stimulated maximal increase in SCC (55.8 ± 4.1, 43.9 ± 3.8 and 93.9 ± 2.7 µA/cm2, respectively), while sulprostone had no apparent effects. GW627368X eliminated OH‐PGE1‐induced SCC and partially PGE2‐induced SCC, leaving butaprost‐induced SCC almost unperturbed. Bumetanide, 20 µM, inhibited between 40% and 80% of the agonist‐induced changes in SCC. In conclusion, compilation of the results on induced SCC by subtype specific receptor agonists for EP receptors and the pattern of induced SCCs inhibited by GW627368X indicate the EP4receptor subtype as the major mediator of PGE2‐induced electrogenic ion secretion with a lesser induction through the EP2receptor subtype.
EXPERIMENTALLY FERMENTED SAUSAGE FROM GOOSE MEAT AND QUALITY ATTRIBUTES
Authors: GULBAZ G. , KAMBER U. 
Published: July 2008

ABSTRACT This research studies various attributes of an experimental fermented goose meat sausage with a view to contributing one more flavor to the product range of the meat industry. In the study, experimental fermented sausages were made from goose meat. Samples were taken from the sausages during the 21‐day maturation period in order to determine changes in the product microflora. Microbiologic analyses were conducted and it was found that the total aerobic mesophyl bacteria count in the samples was between 5.0 × 104 cfu/g and 4.0 × 108 cfu/g, the lactobacilli count between 4.7 × 103 cfu/g and 2.8 × 108 cfu/g, the staphylococ‐micrococcus count between 2.6 × 103 cfu/g and 1.6 × 106 cfu/g and the mold–yeast count between 1.4 × 103 cfu/g and 2.6 × 105 cfu/g. In chemical analyses conducted at the end of the maturation period, the sausages were found to contain 37.2% moisture, 15.8% fat, 27.5% protein, 4.1% ash and to have a pH of 5.2 LA. In a sensorial analysis conducted by a 10‐member group of panelists using a 5‐point scale, the fermented sausages made from goose meat were compared with fermented sausages made from raw and cooked beef. The results of the microbiologic, chemical and sensorial analyses conducted on the goose meat sausages were found to be in harmony with the values for maturated beef sausage, leading to the conclusion that goose meat may be used in fermented sausage technology.PRACTICAL APPLICATIONSThe aims of the present study are to produce new meat formulations for a gradually increasing world population and to promote development of goose breeding. Studies on the presentation of new food products prepared by various food sources offer an effective use of animal protein sources and an increased portion of animal products in economic portions. Moreover, introduction of this type of new meat product extends product varieties and orients consumers toward different alternatives.
OCCURRENCE OF ESCHERICHIA COLIO157:H7/O157, LISTERIA MONOCYTOGENES AND SALMONELLA SPP. IN BEEF SLAUGHTERHOUSE ENVIRONMENTS, EQUIPMENT AND WORKERS
Authors: AKKAYA L. , ALISARLI M. , CETINKAYA Z. , KARA R. , TELLI R. 
Published: July 2008

ABSTRACTEscherichia coli O157/O157:H7, Listeria monocytogenes and Salmonella spp. are major foodborne pathogens and the emergence of these pathogens has been reported in many countries. The aim of this study was to investigate contamination of the beef slaughterhouse environment, equipment and workers with E. coli O157/O157:H7, L. monocytogenes and Salmonella spp. For this study, 500 swab samples were taken from 19 different points in five privately owned slaughterhouses, their periphery, slaughterhouse equipment and slaughterhouse employees. The presence of E. coli O157:H7/O157, L. monocytogenes and Salmonella spp. was determined with the application of the immunomagnetic separation method. Our study showed that the swabs taken from the five slaughterhouses contained E. coli O157:H7 in the environment, equipment, abattoir workers and water with a frequency 0.31, 1, 1.42 and 0%, respectively; while E. coli O157 was evident in the environment, equipment, abattoir workers and water with a ratio of 15, 10, 10 and 0%, respectively; L. monocytogenes was detected in the environment, equipment, abattoir workers and water at a ratio of 4.37, 15, 5.71 and 0%, respectively; and Salmonella spp. occurrence in the environment, equipment, abattoir workers and water at a ratio of 3.43, 16, 11.42, and 0%, respectively. Implementing hazard analysis critical control point principles in work procedures would definitely reduce the gross contamination occurring in abattoirs.PRACTICAL APPLICATIONSThis study has revealed the effect of personnel and equipment on the contamination routes of E. coli O157:H7, Listeria monocytogenes and Salmonella spp. in meat in slaughterhouses and showed that especially L. monocytogenes and Salmonella spp. may pose a higher risk than E. coli O157:H7 in slaughterhouses.