Risk factors affecting third molar autotransplantation in males: a retrospective survey in dental clinics

The aim of this study was to investigate the risk factors affecting long-term prognosis of autotransplantation of third molars with complete root formation in males at dental clinics. Participating dentists were requested to provide information on transplantations they had undertaken from 1 January 1990 to 31 December 2010. Data on a total of 708 teeth from 637 patients were collected. After data screening and elimination, participants of this study consisted of 183 teeth of 171 males ranging from 20 to 72 years of age (mean age, 44·8 years). The cumulative survival rate was 86·0% at the 5-year mark, 59·1% at 10 years and 28·0% at 15 years. The mean survival time was 134·5 months, as calculated by the Kaplan-Meier method. Single factor analysis using the log-rank test showed that the following factors had significant influence (P < 0·05) on survival of transplanted teeth: periodontal disease as the reason for recipient site tooth extraction, fewer than 25 present teeth and Eichner index Groups B1 to C. Cox regression analysis examined five factors: age, smoking habit, recipient site extraction caused by periodontal disease, fewer than 25 present teeth and Eichner index. This analysis showed that two of these factors were significant: fewer than 25 present teeth was 2·63 (95% CI, 1·03-6·69) and recipient site extraction caused by periodontal disease was 3·80 (95% CI, 1·61-9·01). The results of this study suggest that long-term survival of transplanted teeth in males is influenced not only by oral bacterium but also by occlusal status.

Anaplastic meningioma with papillary, rhabdoid, and epithelial features: a case report

A 74-year-old man manifested disturbed consciousness and right hemiparesis. Computed tomography revealed a left frontal parasagittal meningeal tumor with extensive peritumoral brain edema and skull invasion. Subtotal removal was performed. Five years later, he underwent two more operations of massive recurrences. Pathological studies revealed anaplastic meningioma with two different histological areas. One was an epithelial and meningothelial area, and the other was a papillary and rhabdoid area. In the papillary and rhabdoid area, small tumor cells with a high nucleus/cytoplasm ratio proliferated densely around the dilated central capillaries with a pseudopapillary pattern. Many rhabdoid cells (vimentin ++, cytokeratin AE1/AE3 +, epithelial membrane antigen [EMA] + +) tended to be distributed far from the central capillaries. There were many mitotic figures near the central vessels. Dense MIB1-positive nuclei were also observed near the central vessels. The trabecular pattern of the tumor cells in the epithelial area was quite different from the histological features of chordoid meningioma.

Electrical conduction of organic ultrathin films evaluated by an independently driven double-tip scanning tunneling microscope

The electrical transport properties of organic thin films within the micrometer scale have been evaluated by a laboratory-built independently driven double-tip scanning tunneling microscope, operating under ambient conditions. The two tips were used as point contact electrodes, and current in the range from 0.1 pA to 100 nA flowing between the two tips through the material can be detected. We demonstrated two-dimensional contour mapping of the electrical resistance on a poly(3-octylthiophene) thin films as shown below. The obtained contour map clearly provided an image of two-dimensional electrical conductance between two point electrodes on the poly(3-octylthiophene) thin film. The conductivity of the thin film was estimated to be (1-8) × 10(-6) S cm(-1). Future prospects and the desired development of multiprobe STMs are also discussed.

[Ascending aorta-abdominal aorta bypass for a patient with renal hypertension induced by aortitis syndrome; report of a case]

A 58-year-old woman was admitted to our institute. Aortitis syndrome was diagnosed when she was 39 years old. She developed intractable hypertension several years prior, and a computed tomography (CT) scan showed severe calcified stenosis of the descending aorta. The ankle brachial pressure index of the right leg was 0.70 and that of the left leg was 0.63. Plasma renin activity was 4.8 ng/ml/h. Ascending aorta-abdominal aorta bypass grafting was scheduled. The operation was successfully performed under partial cardiopulmonary bypass to control arterial blood pressure. An implanted graft was 14 mm in diameter. The postoperative ankle brachial pressure index of the right leg was 1.07 and that of the left leg was 1.03. Postoperative plasma renin activity was 0.2 ng/ml/h, and three-dimensional CT revealed that the implanted graft was patent. Postoperatively, hypertension was well controlled without medication.

Introduction of formal debate into a postgraduate specialty track education programme in periodontics in Japan

AIM

To evaluate the formal debate as an active learning strategy within a postgraduate specialty track education programme in periodontics.

METHODS

A formal debate was implemented as an active learning strategy in the programme. The participants were full-time faculty, residents and dentists attending special courses at a teaching hospital in Japan. They were grouped into two evenly matched opposing teams, judges and audience. As a preparation for the debate, the participants attended a lecture on critical thinking. At the time of debate, each team provided a theme report with a list of references. Performances and contents of the debate were evaluated by the course instructors and audience. Pre- and post-debate testing was used to assess the participants' objective knowledge on clinical periodontology.

RESULTS

Evaluation of the debate by the participants revealed that scores for criteria, such as presentation performance, response with logic and rebuttal effectiveness were relatively low. Thirty-eight per cent of the participants demonstrated higher test scores after the debate, although there was no statistically significant difference in the mean scores between pre- and post-tests. At the end of the debate, vast majority of participants recognised the significance and importance of the formal debate in the programme.

CONCLUSION

It was suggested that the incorporation of the formal debate could serve as an educational tool for the postgraduate specialty track programme.

Formation and electrical transport properties of pentacene nanorod crystal

The monophasic formation of an uncharted pentacene crystal, the pentacene nanorod, has been investigated. The restricted formation of the pentacene nanorod on a bare mica surface reveals a peculiar surface catalytic crystal growth mode of the pentacene. We demonstrated the charge transport measurements through a single pentacene nanorod and analyzed the data using a periodic hopping conduction model. The results revealed that the pentacene nanorod has a periodic conductive node within their one-dimensional crystal.

Learning climate in dental hygiene education: a longitudinal case study of a Japanese and Canadian programme

Educational climates have been found to have important influences on learning, but little feedback has been obtained from dental hygiene students. The purpose of this study was to gain an understanding of the learning climate in Japanese and Canadian dental hygiene programmes for the purpose of making positive changes. A survey instrument with 10 dimensions relating to learning climate was adapted from business and dental models, and designated as the Dental Hygiene Student Learning Climate Survey (DHS-LCS). Higher scores indicated a more positive and supportive learning climate, and lower scores indicated an environment that is potentially less desirable. Students enrolled in a Japanese and a Canadian dental hygiene programme participated in this four-year study from 2005 to 2008. A total of 402 surveys were returned for an average response rate of 62%. The mean total DHS-LCS score of Canadian students was statistically significantly higher than that of Japanese students (P < 0.001) in all years tested, indicating that the Canadian students' perceptions of their learning environment were more favourable than those of the Japanese students. Based on the analyses of the DHS-LCS data, interventions to improve learning climates were designed and implemented. There were statistically significant improvements (P < 0.01) in DHS-LCS scores of Japanese and Canadian students over the years of the study, suggesting that student-centred interventions improved the perceived learning environment. The instrument appears to be helpful in identifying student concerns and can be used to implement interventions to help support a healthier learning climate.

Regulatory T cells are critical to tolerance induction in presensitized mouse transplant recipients through targeting memory T cells

Memory T cells are a significant barrier to induction of transplant tolerance. However, reliable means to target alloreactive memory T cells have remained elusive. In this study, presensitization of BALB/c mice with C57BL/6 skin grafts generated a large number of OX40(+)CD44(hi)effector/memory T cells and resulted in rapid rejection of donor heart allografts. Recognizing that anti-OX40L monoclonal antibody (mAb) (alpha-OX40L) monotherapy prolonged graft survival through inhibition and apoptosis of memory T cells in presensitized recipients, alpha-OX40L was added to the combined treatment protocol of LF15-0195 (LF) and anti-CD45RB (alpha-CD45RB) mAb-a protocol that induced heart allograft tolerance in non-presensitized recipients but failed to induce tolerance in presensitized recipients. Interestingly, this triple therapy restored donor-specific heart allograft tolerance in our presensitized model that was associated with induction of tolerogenic dendritic cells and CD4(+)CD25(+)Foxp3(+) T regulatory cells (Tregs). Of note, CD25(+) T cell depletion in triple therapy recipients prevented establishment of allograft tolerance. In addition, adoptive transfer of donor-primed effector/memory T cells into tolerant recipients markedly reduced levels of Tregs and broke tolerance. Our findings indicated that targeting memory T cells, by blocking OX40 costimulation in presensitized recipients was very important to expansion of Tregs, which proved critical to development of tolerance.

Cloning and expression of cDNA for salmon growth hormone in Escherichia coli

cDNA clones encoding chum salmon (Oncorhynchus keta) growth hormone (sGH) have been isolated from a cDNA library prepared from chum salmon pituitary gland poly(A)(+) RNA. Synthetic oligodeoxynucleotide mixtures based on amino acid residues 23-28 of sGH were used as hybridization probes to select recombinant plasmids carrying the sGH coding sequence. The complete nucleotide sequence of sGH cDNA has been determined. The cDNA sequence codes for a polypeptide of 210 amino acids, including a putative signal sequence of 22 amino acids. The 5' and 3' untranslated regions of the message were 64 and 426 bases long, respectively. Mature sGH was efficiently expressed in Escherichia coli carrying a plasmid in which the sGH cDNA was under control of the E. coli trp promoter; sGH comprised about 15% of the total cellular protein in such bacteria. The partially purified sGH from E. coli stimulated the growth of rainbow trout and the activity was indistinguishable from that of natural sGH.

Percutaneous sclerotherapy for arteriovenous malformations of the face in the outpatient clinic

Sclerotherapy for arteriovenous malformations has to be performed under general anaesthesia because of the pain during injection and the need of careful monitoring. Two cases with arteriovenous malformations of the face regions are presented in whom percutaneous sclerotherapy was performed under local anaesthesia in the outpatient clinic. The sessions were uneventful and there was a visible decrease in the overall size and an improvement in skin colour of the lesion could be seen. Sclerotherapy can be used in the outpatient clinic to treat arteriovenous malformations that have a slow flow or a venous outflow that can be compressed to artificially slow the flow during injection.