Relationship between the prognosis of periodontitis and occlusal force during the maintenance phase--a cohort study

BACKGROUND AND OBJECTIVE

Few studies have longitudinally investigated the relationship between periodontal disease progression and occlusal factors in individual subjects during the maintenance phase of periodontal therapy. The aim of this cohort study was to investigate the relationship between biting ability and the progression of periodontal disease in the maintenance phase.

MATERIAL AND METHODS

A total of 194 patients were monitored for 3 years during the maintenance phase of periodontal therapy. The subjects with disease progression (Progress group) were defined based on the presence of >or= 2 teeth demonstrating a longitudinal loss of proximal attachment of >or= 3 mm or tooth-loss experience as a result of periodontal disease during the study period. The subjects with high occlusal force were diagnosed as men who showed an occlusal force of more than 500 N and women who showed an occlusal force of more than 370 N. The association between biting ability and the progression of periodontitis was investigated using logistic regression analysis.

RESULTS

There were 83 subjects in the Progress group and 111 subjects in the Non-progress group. A backward, stepwise logistic regression model showed that the progression of periodontal disease was significantly associated with the presence of one or more teeth with a high clinical attachment level (CAL) of >or= 7 mm (odds ratio: 2.397; 95% confidence interval: 1.306-4.399) ( p = 0.005) and low occlusal force (odds ratio: 2.352; 95% confidence interval: 1.273-4.346) ( p = 0.006).

CONCLUSION

The presence of one or more teeth with a high CAL of >or= 7 mm and low occlusal force might be possible risk factors for periodontal progression in the maintenance phase of periodontal therapy.

Near-threshold Lambda(1520) production by the gamma(p)-->K{+}Lambda(1520) reaction at forward K+ angles

Differential cross sections and photon-beam asymmetries for the gamma(p)-->K{+}Lambda(1520) reaction have been measured with linearly polarized photon beams at energies from the threshold to 2.4 GeV at 0.6<cos(theta){c.m.}{K}<1. A new bump structure was found at W approximately 2.11 GeV in the cross sections. The bump is not well reproduced by theoretical calculations introducing a nucleon resonance with J<or=3/2. This result suggests that the bump might be produced by a nucleon resonance possibly with J>or=5/2 or by a new reaction process, for example, an interference effect with the phi photoproduction having a similar bump structure in the cross sections.

Salvage esophagectomy after definitive chemoradiotherapy for synchronous double cancers of the esophagus and head-and-neck

Head-and-neck cancer is frequently associated with esophageal cancer. Because the operative procedures for these synchronous double cancers are too invasive, definitive chemoradiotherapy tends to be applied as an initial treatment. A salvage esophagectomy for either recurrent or residual disease after definitive chemoradiotherapy in patients with such double cancer has never been reported. We reviewed 21 patients with esophageal cancer who underwent a salvage esophagectomy after definitive chemoradiotherapy. Among them, the treatment course of five patients who underwent a salvage esophagectomy for patients with synchronous double cancers of the esophagus and head-and-neck region was analyzed. Because head-and-neck cancer was well controlled after chemoradiotherapy in all five patients, a salvage esophagectomy was indicated for either recurrent or residual esophageal cancer after definitive chemoradiotherapy. Anastomotic leakage developed in four patients; however, no other complications including pulmonary complications were recognized. All of them were discharged to home and three of them are still alive without any recurrence for 20-43 months. A salvage esophagectomy should be considered as a treatment option for either recurrent or residual esophageal cancer with well-controlled head-and-neck cancer after definitive chemoradiotherapy when complete resection of the esophagus is expected.

62 RECOVERY OF CELL NUCLEI FROM 15 000-YEAR-OLD MAMMOTH TISSUES AND INJECTION INTO MOUSE ENUCLEATED MATURED OOCYTES

Since the report of “Dolly” (Wilmut et al. 1997 Nature 385, 810-813), cloned animals have been successfully produced by somatic cell nuclear transfer (SCNT). In those reports, cultured or fresh cells were mainly used as nuclear donor cells in SCNT. Meanwhile, there was a report of the birth of offspring by SCNT with the nuclear donor cell derived from frozen whole body kept at -20°C for 16 years without cryoprotectant (Wakayama et al. 2008 Proc. Natl. Acad. Sci. USA 105, 17 318-17 322). This report suggests that if tissues or cells are cryopreserved postmortem without cryoprotectant, resurrection of the postmortem animal individual might be possible by SCNT. Furthermore, in cases of extinct or endangered species, it is difficult to use oocytes derived from same species as the recipient cytoplasm. However, there was a report of the birth of offspring by SCNT with oocytes derived from closely related species (Lanza et al. 2000 Cloning 2, 79-90). This result suggests that if oocytes from closely related species are available as the recipient cytoplasm, it would be possible to resurrect extinct or endangered species by SCNT. Woolly mammoth (Mammuthus primigenius) is a famous animal that existed during the ice ages and became extinct at the end of the last ice age. Its relics have been excavated from permafrost. Recently, the prospect of the resurrection of woolly mammoth by SCNT has heightened. However, even if the soft tissue of the woolly mammoth is excavated, it is not clear whether its cell nuclei retain their biological characteristics for more than several thousand years. In this study, we recovered cell nuclei from 15 000-year-old mammoth tissues and injected them into mouse enucleated matured oocytes as the nuclear donor in SCNT. Frozen mammoth legs were excavated from Northeast Siberian permafrost at the point of 71°34′56.9″ N and 141°37′37.6″ E. The conventional radiocarbon age of the sample after 13C correction was 13 100 to 12800 BC or 12400 to 11 800 BC. Cell nucleus-like structures were successfully recovered from skin and muscle tissues. Those nuclei were then injected into enucleated BDF1 mouse oocytes, and more than half of the injected oocytes were able to survive (67%; 12/18 for oocytes injected with skin-derived nucleus, 55%; 72/131 for oocytes injected with muscle-derived nucleus and 33%; 26/80 for oocytes injected with frozen-thawed mouse bone marrow-derived nucleus as the control group). Injected nuclei were not taken apart and retained their nuclear structure. Those oocytes did not show disappearance of nuclear membrane or premature chromosome condensation at 1 h after injection and did not form pronuclear-like structures at 7 h after injection. Because one-half of the oocytes injected with nuclei derived from frozen-thawed mouse bone marrow cells were able to form pronuclear-like structures (46%; 12/26), it might be possible to promote the cell cycle of nuclei from ancient animal tissues by suitable pretreatment in SCNT. This is the first report of SCNT with nuclei derived from mammoth tissues. This study was funded in part by Gifu Prefecture, Japan.

70 FIBROBLAST GROWTH FACTOR 4 PROMOTES THE DEVELOPMENT OF SOMATIC CELL NUCLEAR TRANSFER EMBRYOS IN MICE

Somatic cell nuclear transfer (SCNT) embryos can develop during the preimplantation period; however, most of these die after implantation period. A transcription factor, Cdx2, promotes differentiation of extraembryonic tissues and appears to be involved in the segregation of inner cell mass (ICM) and trophectoderm (TE) in preimplantation embryos. So far, we have demonstrated that the expression of Cdx2 in mouse SCNT embryos is delayed and its expression level is significantly lower than that in intracytoplasmic sperm injection (ICSI) embryos. Moreover, the ectopic expression of Oct-3/4 was observed in the TE tissues of SCNT blastocysts, but not in ICSI blastocysts. Fibroblast growth factor (FGF) receptor 2 (FGFR2) is specifically expressed in 8-cell to morula-stage embryos and trophectoderm (TE) and is essential for implantation; however, FGFR2 expression in SCNT embryos significantly decreases compared with IVF embryos. Therefore, it is likely that abnormality of differentiation that is controlled in development of pre-implantation in SCNT embryos leads to a rapid decrease of subsequent developmental ability. Then, we investigated the effects of FGF4 on development of SCNT embryos. Mouse SCNT embryos were produced according to the method reported previously (Wakayama et al. 1998). B6D2F1 and B6C3F1 female mice were used for the collection of recipient oocytes and donor cells, respectively. Data were analyzed by Student’s t-test. First, the timing to start adding FGF4 was decided by FGFR2 expression time about 54 h after cell injection and treated for 3, 6, 12, 24, and 42 h thereafter. In the case of FGF4 concentration at 25 ng mL-1 with treating time of 6 h from the 4- to 8-cell stages, SCNT embryos significantly promoted the development to morula and blastocyst stages (91 and 45%, respectively) compared with IVF embryos (80 and 30%, respectively; P < 0.05). However, longer treatment of 42 h with FGF4 made their morphology considerably worse. Then, concentrations of FGF4 at 5, 25, 50, 250, and 500 ng mL-1 with treating time of 6 h was examined. In case of FGF4 concentration at 25 and 50 ng mL-1, SCNT embryos significantly promoted the development to morula and blastocyst stages (P < 0.05). Immunohistochemical analysis showed segregation of the expression of Oct-3/4 and Cdx2 in ICM and TE, respectively, in FGF4-treated SCNT embryos, unlike in the case of nontreated SCNT embryos, which showed an ectopic expression of Oct-3/4 in TE tissues. Furthermore, after the transplantation of SCNT embryos treated with FGF4 at 50 ng mL-1 and the treating time of 6 h to recipient mice, most of the transferred embryos implanted and cloned mice were successfully produced as well as nontreated SCNT embryos. Therefore, FGF4 facilitates the development of SCNT embryos especially to the morula and blastocyst stages. This work was supported by a Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science.

Induction of immune responses to a human immunodeficiency virus type 1 epitope by novel chimeric influenza viruses

Mucosal and systemic immune responses play an important role in the prevention of infections, including infection with human immunodeficiency virus type 1 (HIV-1). Influenza virus can efficiently induce mucosal and systemic immune responses, and thus, chimeric influenza viruses expressing the peptides derived from HIV-1 proteins have been generated to elicit immune responses against the inserted peptide. Novel chimeric influenza viruses were generated with full length of the V3-loop of gp120 or cytotoxic T-lymphocyte epitope of gag from HIV-1 inserted into the stalk of NA (NA-V3 and NA-gag, respectively) and the V3-loop was inserted into the intracellular domain of M2 (M2-V3). The immune responses of mice infected with these chimeric influenza viruses were investigated. The intranasal infection of NA-gag induced gag epitopespecific CTLs and the intranasal infection of NA-V3 and M2-V3 induced V3-specific antibodies. The serum from mice infected with NA-V3 neutralized a clinical isolate of HIV-1 and the infection of NA-V3 induced V3-specific secretory antibodies. These results suggest that intranasal infection of these chimeric influenza viruses could induce both humoral and cellular immune responses against an inserted foreign peptide and therefore could be a potential candidate for use as an HIV-1 vaccine.

Relationship between folic acid intake and gingival health in non-smoking adults in Japan

OBJECTIVE

To assess the relationship between dietary intake of folate and gingival bleeding in non-smoking adults in Japan.

MATERIALS AND METHODS

Data were obtained from residents who participated in the regional nutrition survey and survey of dental diseases conducted by the administrative office of northernmost prefecture of Japan. Dietitians visited households to collect data on dietary intake. Clinical parameters, including Community Periodontal Index (CPI) and bleeding on probing (BOP), were examined in community centers. Information on smoking habit was obtained from the interview. Then the data from 497 non-smoking adults with 20 teeth or more, aged 18 years or older, were analyzed. The relationship between dietary intake of folic acid and gingival bleeding status was estimated using multivariate analysis.

RESULTS

Pearson's correlation coefficient showed a significant negative correlation between dietary folate level and bleeding on probing. The negative association between folate level and bleeding on probing remained statistically significant in multiple regression analysis (standardized beta = -0.204, P < 0.001). However, no significant association was found between CPI scores and folate intake level.

CONCLUSIONS

The results suggest that dietary intake of folic acid, an important indicator of gingival bleeding in adults, may provide an important clinical target for intervention to promote gingival health.

Relationships between patient characteristics and reasons for tooth extraction in Japan

OBJECTIVES

The purpose of this study was to examine the relationships between patient characteristics and reasons for extraction of permanent teeth.

METHODS

5131 dentists were selected from the list of the membership directory of the Japan Dental Association by systematic random selection. The dentists were asked to record the reason for each extraction of permanent teeth during a period from February 1 to 7, 2005. Reasons for tooth extraction were assigned to five groups: caries, fracture of teeth weakened by caries or endodontics, periodontal diseases, orthodontics and other reasons. We used cross tabulation and multiple logistic regression analysis to estimate the relationships between patient characteristics and reasons for tooth extraction.

RESULTS

2001 dentists (response rate of 39.0%) returned the forms, and complete information on 7333 patients was obtained. A total of 3,196 (43.6%) patients underwent tooth extraction due to caries and its sequela, and 2721 (37.1%) patients underwent tooth extraction due to periodontal disease. Multiple logistic regression analysis showed that denture wearers were more likely to undergo tooth extraction due to periodontal disease in all age groups (p < 0.05). Males tended to undergo tooth extraction due to periodontal disease than did females in all age groups (p < 0.05) except for age group 30-49. Subjects with 19 or less teeth were more likely to undergo tooth extraction due to periodontal disease in the age groups 30-49 (p < 0.001) and 50-69 (p < 0.001). In the age group of 50 years or older, female (p<0.01) and the possession of 20 or more natural teeth (p < 0.05) were related to caries extraction. However, there was no clear relationship between caries extraction and patient characteristics under 50 years old.

CONCLUSION

There was a significant relationship between denture wearing and periodontal extraction. In the middle aged population, patients with 19 or less teeth lost their teeth mainly due to periodontal disease.

The prognostic impact of hypoxia-inducible factor-1α and VEGF, IGF-2, p21, p53 expression in gastric adenocarcinoma

4571

Background: Hypoxia caused by either radiation or chemotherapy induces various intracellular adaptive responses, which contribute to tumor progression. The clinicopathological characteristics of human gastric cancer and the clinical outcomes were analyzed to investigate the effects of the expression of hypoxia-inducible factor1α (HIF-1α) and some related proteins, such as, vascular endothelial growth factor (VEGF), insulin-like growth factor-2 (IGF-2), p21, and p53 on the prognosis of human gastric cancer. Methods: The expressions of HIF-1α, VEGF, IGF-2, p21, and p53 proteins were determined by immunohistochemistry in 216 specimens of primary gastric cancer. Results: Of all 216 patients, 85 (39.4%) showed a positive expression of HIF-1α. In addition, the HIF-1α expression positively correlated with the tumor size and depth of invasion, while it was also more frequent in tumors with lymphatic invasion and undifferentiated adenocarcinomas. Though the VEGF expression significantly correlated with the HIF-1α expression, the expressions of IGF-2, p21 and p53 did not show any correlation. HIF-1α-positive/p21-negative tumors had a lower apoptotic index, and the patients with such tumors also had a significantly poorer prognosis. Similarly, HIF-1α-positive/p53-positive tumors had a significantly poorer prognosis. A multivariate Cox regression analysis showed the depth of invasion, lymph node metastasis, and HIF-1α positivity to all be independent prognostic factors in patients with gastric cancer. Conclusions: Based on the above findings, HIF-1α is therefore considered to be a useful independent prognostic factor in gastric cancer, and the combination of a HIF-1α protein overexpression with the loss of p21 expression or nonfunctional p53 thus tends to indicate a dismal prognosis. Controlling hypoxia, especially in the HIF-1α pathways, may therefore hold the key to a greater individualization of therapy and also lead to the development of new treatments for patients with gastric cancer.

No significant financial relationships to disclose.

A phase I trial of S-1 plus vinorelbine in patients with unresectable advanced or metastatic non-small cell lung cancer

e19098

Background: We reported the efficacy of the combination treatment of tegafur-uracil (UFT) and vinorelbine (VNR) for the elderly patients (pts) (>70) with advanced non-small cell lung cancer (NSCLC) in ASCO 2007 (Abstract - No. 18075). Although the cisplatin-based doublets are still milestone for the pts with advanced NSCLC, non-platinum based doublet regimens remain as a matter of development judging from recent meta-analysis. Tegafur-5-chloro-2,4-dihydroxypyridine-potassium oxonate (S-1), a new oral fluoropyrimidine, has been studied extensively, and appears promising for various kinds of cancers including NSCLC. Thus, we conducted this phase I trial using VNR and new oral fluoropyrimidine, S-1. Methods: Pts with advanced NSCLC, who had received at least one prior platinum-containing regimen, were eligible. In this phase I study, VNR was infused on days 1 and 8, and S-1 was administered from day 2 to day 6 and from day 9 to day 13 of a 3-week cycle. The starting dose of S-1 was 80 mg/m2/day and, if necessary, the dose was decreased to 65 mg/m2/day; VNR was increased from 20 to 25 mg/m2 in this trial. Results: From August 14, 2007 to April 1, 2008, 8 pts enrolled in this study. Median age was 61 (range 49–75). Dose limiting toxicity (DLT) was evaluated during the first 6 weeks of the treatment. No DLT was observed at dose level I (80 mg/m2/day S-1, 20 mg/m2 VNR). At dose level II (80 mg/m2/day S-1, 25 mg/m2 VNR), DLT in the form of neutropenia, hyperglycemia and hyponatremia was observed in 3 of 5 pts. The maximum tolerated dose (MTD) for the present treatment was 80 mg/m2/day S-1 and 25 mg/m2 VNR; the recommended tolerable dose for future phase II trials is therefore 80 mg/m2/day S-1 and 20 mg/m2 VNR. Conclusions: Three-week cycle of VNR (20 mg/m2), infused on days 1 and 8; S-1 (80 mg/m2/day), administered from day 2 to day 6 and from day 9 to day 13, is being examined in our phase II trial for first-or second-line treatment of NSCLC.

No significant financial relationships to disclose.

Cross sections and beam asymmetry for K;{+}Sigma;{*-} photoproduction from the deuteron at E_{gamma}=1.5-2.4 GeV

The Sigma(1385) resonance, or Sigma;{*}, is well known as part of the standard baryon decuplet with spin J=3/2. Measurements of the reaction gammap-->K;{+}Sigma;{*0} are difficult to extract due to overlap with the nearby Lambda(1405) resonance. However, the reaction gamman-->K;{+}Sigma;{*-} has no overlap with the Lambda(1405) due to its charge. Here we report the first measurement of cross sections and beam asymmetries for photoproduction of the Sigma;{*-} from a deuteron target. The cross sections at forward angles range from 0.4 to 1.2 mub, with a broad maximum near E_{gamma} approximately 1.8 GeV. The beam asymmetries are negative, in contrast with positive values for the gamman-->K;{+}Sigma;{-} reaction.

Association of single nucleotide polymorphisms in the endothelial differentiation sphingolipid G-protein-coupled receptor 1 gene with marbling in Japanese Black beef cattle

Marbling defined by the amount and distribution of intramuscular fat, so-called Shimofuri, is an economically important trait of beef cattle in Japan. The endothelial differentiation sphingolipid G-protein-coupled receptor 1 (EDG1) gene, involved in blood vessel formation, has been previously shown to be expressed at different levels in musculus longissimus muscle between low-marbled and high-marbled steer groups. It is located within the genomic region of a quantitative trait locus for marbling, and thus was considered as a positionally functional candidate for the gene responsible for marbling. In this study, two single nucleotide polymorphisms (SNPs) in the 5' untranslated region (UTR) and the 3' UTR of EDG1, referred to as c.-312A>G and c.*446G>A, respectively, were detected between the two steer groups. The two SNPs were associated with the predicted breeding value for beef marbling standard number by analyses using a population of Japanese Black beef cattle. The effect of genotypes at each of the SNPs on the predicted breeding value for subcutaneous fat thickness was not statistically significant (P > 0.05). Reporter gene assays revealed no significant differences in gene expression between alleles at each of the SNPs. These findings suggest that EDG1 SNPs, although they may not be regarded as a causal mutation, may be useful for effective marker-assisted selection to increase the levels of marbling in Japanese Black beef cattle.