A primary canine and an impacted permanent canine with infection potentially induced an intracranial abscess.

Intracranial abscess is a rare but life-threatening disease. There have been no reports on intracranial abscess induced by the residual primary tooth and the impacted successive permanent tooth with infection. We report on an interesting case of a 29-year-old man suffering from an epidural abscess, potentially caused by an infection of the residual primary maxillary right canine and the impacted permanent maxillary right canine. The patient recovered completely after prolonged antibiotic treatment and extraction of both of the suspected teeth. Fusobacterium sp. was isolated from the culture of a peripheral blood sample. This case alerts us to realize that the lack of suitable and timely intervention in oral conditions might produce a harmful effect on general health.

Effect of γ-cyclodextrin as a lyoprotectant for freeze-dried actinidin.

Actinidin (ATD) is a cysteine protease found in kiwifruit. It is used to tenderize meat and to enhance the digestion of proteins in the small intestine. However, ATD is unstable during freeze-drying, which alters its bioactivity. It is well known that sugars have the ability to protect proteins from the stress of freeze-drying. In this study, we investigated the protective effect of various saccharides on the stability of ATD during freeze-drying. The ATD activities of the samples containing γ-cyclodextrin (CyD) showed only a small decrease, and compared with trehalose and sucrose, γ-CyD was a more effective stabilizer for ATD. Secondary structural changes in freeze-dried ATD were observed by circular dichroism spectroscopy and compared with the changes in stabilized samples. There was a close relationship between the α-helix content and the stabilization. The sugars stabilized the protein by suppressing the changes in the α-helix. Fourier transform infrared spectroscopy measurement showed that the amide I band of ATD with γ-CyD was shifted to a lower wavenumber compared with other sugars. Therefore, stronger hydrogen bonds may be formed between ATD and γ-CyD than between ATD and other sugars. The suppression of changes in the protein secondary structure accompanying the formation of hydrogen bonding between the protein and the sugar also contributed to the protective effect of the sugars.

3-T MRI safety assessments of magnetic dental attachments and castable magnetic alloys.

OBJECTIVES: To assess the safety of different magnetic dental attachments during 3-T MRI according to the American Society for Testing and Materials F2182-09 and F2052-06e1 standard testing methods and to develop a method to determine MRI compatibility by measuring magnetically induced torque. METHODS: The temperature elevations, magnetically induced forces and torques of a ferromagnetic stainless steel keeper, a coping comprising a keeper and a cast magnetic alloy coping were measured on MRI systems. RESULTS: The coping comprising a keeper demonstrated the maximum temperature increase (1.42 °C) for the whole-body-averaged specific absorption rate and was calculated as 2.1 W kg⁻¹ with the saline phantom. All deflection angles exceeded 45°. The cast magnetic alloy coping had the greatest deflection force (0.33 N) during 3-T MRI and torque (1.015 mN m) during 0.3-T MRI. CONCLUSIONS: The tested devices showed minimal radiofrequency (RF)-induced heating in a 3-T MR environment, but the cast magnetic alloy coping showed a magnetically induced deflection force and torque approximately eight times that of the keepers. For safety, magnetic dental attachments should be inspected before and after MRI and large prostheses containing cast magnetic alloy should be removed. Although magnetic dental attachments may pose no great risk of RF-induced heating or magnetically induced torque during 3-T MRI, their magnetically induced deflection forces tended to exceed acceptable limits. Therefore, the inspection of such devices before and after MRI is important for patient safety.

Bowen disease of the palm associated with human papillomavirus 52.

Human papillomavirus (HPV) is a well-known risk factor for many human cancers, especially cervical cancers. Among the nonmelanoma skin cancers, Bowen disease (BD) of the genitalia and fingers has also been shown to be closely associated with the high-risk types of HPV, especially HPV16. We report a case of BD of the palm, which is a very rare location for BD. In addition to its rare location, HPV52, which is classified as a mucous high-risk HPV type, was detected in the lesion by PCR restriction fragment length polymorphism analysis. To our knowledge, this is the first reported case of BD associated with HPV52.

Radiofrequency heating of metallic dental devices during 3.0 T MRI.

OBJECTIVES: To estimate the risk of injury from radiofrequency (RF) heating of metallic dental devices in use during 3.0 T MRI. METHODS: The whole-body specific absorption rate (WB-SAR) was calculated on the basis of saline temperature elevation under the maximum RF irradiation for 15 min to determine the operation parameters for the heating test. The temperature changes of three types of three-unit bridges, a full-arch fixed dental prosthesis and an orthodontic appliance in use during MRI with a 3.0 T MR system (Magnetom(®) Verio; Siemens AG, Erlangen, Germany) were then tested in accordance with the American Society for Testing and Materials F2182-09 standardized procedure under the maximum RF heating during 15 min RF irradiation. RESULTS: The system console-predicted WB-SAR was approximately 1.4 W kg(-1) and that measured with a saline phantom was 2.1 W kg(-1). In the assessment of RF heating, the highest temperature increase was +1.80 °C in the bridges, +1.59 °C in the full-arch fixed dental prosthesis and +2.61 °C in the orthodontic appliance. CONCLUSIONS: The relatively minor RF heating of dental casting material-based prostheses in Magnetom Verio systems in the normal operating mode should not pose a risk to patients. However, orthodontic appliances may exhibit RF heating above the industrial standard (CENELEC standard prEN45502-2-3); therefore, the wire should be removed from the bracket or a spacer should be used between the appliance and the oral mucosa during MRI.

Radiofrequency heating and magnetically induced displacement of dental magnetic attachments during 3.0 T MRI.

OBJECTIVE: The aim of this study was to estimate the risk of injury from dental magnetic attachments due to their radiofrequency (RF) heating and magnetically induced displacement during 3.0 T MRI. METHODS: To examine the magnetic attachments, we adopted the American Society for Testing and Materials F2182-02a and F2052-06 standards in two MRI systems (Achieva 3.0 T Nova Dual; Philips, Tokyo, Japan, and Signa HDxt 3.0 T; GE Healthcare, Milwaukee, WI). The temperature change was measured in a cylindrical keeper (GIGAUSS D600; GC, Tokyo, Japan) with coping of the casting alloy and a keeper with a dental implant at the maximum specific absorption rate (SAR) for 20 min. To measure the magnetically induced displacement force, three sizes of keepers (GIGAUSS D400, D600 and D1000) were used in deflection angle tests conducted at the point of the maximum magnetic field strength. RESULTS: Temperature elevations of both coping and implant were higher in the Signa system than in the Achieva system. The highest temperature changes in the keeper with implant and keeper with coping were 0.6 °C and 0.8 °C in the Signa system, respectively. The temperature increase did not exceed 1.0 °C at any location. The deflection angle (α) was not measurable because it exceeded 90°. GIGAUSS D400 required an extra 3.0 g load to constrain the deflection angle to less than 45°; GIGAUSS D600 and D1000 required 5.0 and 9.0 g loads, respectively. CONCLUSIONS: Dental magnetic attachments pose no risk due to RF heating and magnetically induced displacement at 3.0 T MRI. However, it is necessary to confirm that these keepers are securely attached to the prosthesis before imaging.

Targeting fibroblast growth factor receptor 3 enhances radiosensitivity in human squamous cancer cells.

Conventional therapies including radiation therapy cannot cure squamous cell carcinoma (SCC), and new treatments are clearly required. Our recent studies have shown that SCC cell lines exhibiting radioresistance show significant upregulation of the fibroblast growth factor receptor 3 (FGFR3) gene. We hypothesized that inhibiting FGFR3 would suppress tumor cell radioresistance and provide a new treatment approach for human SCCs. In the present study, we found that RNA interference-mediated FGFR3 depletion in HSC-2 cells, a radioresistant cell line, induced radiosensitivity and inhibited tumor growth. Use of an FGFR3 inhibitor (PD173074) obtained similar results with suppression of the autophosphorylation extracellular signal-regulated kinase pathway in HSC-2 cells and lung cancer cell lines. Moreover, the antitumor growth effect of the combination of PD173074 and radiation in vivo was also greater than that with either drug alone or radiation alone. Our results provided novel information on which to base further mechanistic study of radiosensitization by inhibiting FGFR3 in human SCC cells and for developing strategies to improve outcomes with concurrent radiotherapy.

Nuclear factor kappa B plays a pivotal role in polyinosinic-polycytidylic acid-induced expression of human ß-defensin 2 in intestinal epithelial cells.

Intestinal epithelial cells (IECs) play an important role in protecting the intestinal surface from invading pathogens by producing effector molecules. IECs are one of the major sources of human beta-defensin 2 (hBD-2), and can produce it in response to a variety of stimuli. Although IECs express Toll-like receptor 3 (TLR-3) and can respond to its ligand, double-stranded RNA (dsRNA), hBD-2 expression in response to dsRNA has not been elucidated. In the present study, using an artificial analogue of dsRNA, polyinosinic-polycytidylic acid (poly I:C), we investigated whether the human IEC line, HT-29, can produce hBD-2 in response to poly I:C. HT-29 cells can express hBD-2 mRNA only when stimulated with poly I:C. The induction of hBD-2 mRNA expression was observed at 3 h after stimulation and peaked at 12 h of post-stimulation. Pre-incubation of the cells with nuclear factor kappa B (NF-κB)-specific inhibitor, l-1-4'-tosylamino-phenylethyl-chloromethyl ketone (TPCK) and isohelenine abolished the expression of hBD-2. Detection of the poly I:C signal by TLR-3 on the surface of HT-29 cells was revealed by pre-incubating the cells with anti-TLR-3 antibody. The 5'-regulatory region of the hBD-2 gene contains two NF-κB binding sites. A luciferase assay revealed the importance of the proximal NF-κB binding site for poly I:C-induced expression of hBD-2. Among NF-κB subunits, p65 and p50 were activated by poly I:C stimulation and accumulated in the nucleus. Activation of the p65 subunit was investigated further by determining its phosphorylation status, which revealed that poly I:C stimulation resulted in prolonged phosphorylation of p65. These results indicate clearly that NF-κB plays an indispensable role in poly I:C induced hBD-2 expression in HT-29 cells.

Patterns of missing occlusal units and oral health-related quality of life in SDA patients.

The aim of this study was to explore the relationship between patterns of missing occlusal units (OUs) and oral health-related quality of life (OHRQoL) in subjects with the shortened dental arches (SDAs). Subjects with SDAs were recruited consecutively for 1 month from six university-based prosthodontic clinics. In total, 115 SDA subjects participated (mean age, 58.5 +/- 10.0 years; 71% female). The location and number of missing teeth were examined and the number of missing OUs was calculated. To evaluate OHRQoL, the Japanese version of the Oral Health Impact Profile (OHIP-J) was administered and the summary score of OHIP-J was calculated. The SDA subjects were categorized depending upon the anterior-posterior lengths of the missing or remaining OUs. Regression analyses were performed to investigate the OHIP-J differences between groups of subjects with various anterior-posterior SDA lengths. The analyses revealed that subjects who only lost the second molar contact exhibited significantly better OHRQoL than those who lost more teeth [coefficient: 11.1, 95% confidence interval (CI): 2.8-19.2, P = 0.02]. Furthermore a statistically significant group difference was observed between the groups with and without the first molar occlusal contact (coefficient: 12.8, 95% CI: 1.4 to 24.1, P = 0.03). In conclusion, although our results are of exploratory nature and need validation, patterns of missing OUs are likely to be related to the OHRQoL impairment in SDA subjects with the presence of first molar contact having a particularly important role.

Inhibition of ICAM2 induces radiosensitization in oral squamous cell carcinoma cells.

We recently identified genes and molecular pathways related to radioresistance of oral squamous cell carcinoma (OSCC) using Affymetrix GeneChip. The current study focused on the association between one of the target genes, intercellular adhesion molecule 2 (ICAM2), and resistance to X-ray irradiation in OSCC cells, and evaluated the antitumor efficacy of combining ICAM2 small interfering RNA (siRNA) and X-ray irradiation. Downregulation of ICAM2 expression by siRNA enhanced radiosensitivity of OSCC cells with the increased apoptotic phenotype via phosphorylation (ser473) of AKT and activation of caspase-3. Moreover, overexpression of ICAM2 induced greater OSCC cell resistance to the X-ray irradiation with the radioresistance phenotype. These results suggested that ICAM2 silencing is closely related to sensitivity of OSCC cells to radiotherapy, and that ICAM2 may be an effective radiotherapeutic target for this disease.

Network-based analysis of calcium-binding protein genes identifies Grp94 as a target in human oral carcinogenesis.

To characterise Ca(2+) -binding protein gene expression changes in oral squamous cell carcinomas (OSCCs), we compared the gene expression profiles in OSCC-derived cell lines with normal oral tissues. One hundred Ca(2+) -binding protein genes differentially expressed in OSCCs were identified, and genetic pathways associated with expression changes were generated. Among genes mapped to the network with the highest significance, glucose-regulated protein 94 kDa (Grp94) was evaluated further for mRNA and protein expression in the OSCC cell lines, primary OSCCs, and oral premalignant lesions (OPLs). A significant (P<0.001) overexpression of Grp94 protein was observed in all cell lines compared to normal oral epithelium. Immunohistochemical analysis showed highly expressed Grp94 in primary OSCCs and OPLs, whereas most of the corresponding normal tissues had no protein immunoreaction. Real-time quantitative reverse transcriptase-PCR data agreed with the protein expression status. Moreover, overexpression of Grp94 in primary tumours was significantly (P<0.001) correlated with poor disease-free survival. The results suggested that Grp94 may have potential clinical application as a novel diagnosis and prognostic biomarker for human OSCCs.

Activation of phosphatidylinositol 3-kinase/protein kinase B pathway by a vanadyl compound mediates its neuroprotective effect in mouse brain ischemia.

We previously reported that orthovanadate composed of vanadate (V(5+)) activates phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling through inhibition of protein tyrosine phosphatases, thereby eliciting neuroprotection in brain ischemia/reperfusion injury. However, therapeutic doses of orthovanadate are associated with diarrhea due to inhibition of ATPase. By contrast, vanadyl (V(4+)) organic compounds show low cytotoxicity. Since both vanadate and vanadyl inhibit protein tyrosine phosphatases, we tested whether bis(1-oxy-2-pyridinethiolato)oxovanadium(IV) [VO(OPT)] in a vanadyl form elicits a neuroprotection in brain ischemia. In a mouse transient middle cerebral artery occlusion (MCAO) model, pre- and post-treatments with VO(OPT) significantly reduced infarct volume in a dose-dependent manner. Like orthovanadate, activation of the PI3K/Akt pathway mediated neuroprotective action. VO(OPT) treatment inhibited reduced Akt phosphorylation at Ser-473 following brain ischemia and restored decreased phosphorylation of forkhead box class O (FOXO) family members such as FKHR, FKHRL1, and AFX. Consistent with inhibition of FOXO dephosphorylation, VO(OPT) treatment blocked elevated expression of Fas-ligand, Bim and active caspase-3 24 h after ischemia/reperfusion. Taken together, a vanadyl compound, VO(OPT) elicits neuroprotective effects on brain ischemia/reperfusion injury without apparent side effects.

Quality of life and masticatory function in denture wearers.

Successful prosthodontic treatments for a patient with removable partial dentures including maxillofacial prostheses hopefully brings about psychological wellbeing as well as improved health. The purpose of this study was to investigate the relationship between quality of life (QOL) and the various aspects of denture function. At first, a questionnaire with a visual analog scale with 16 question items concerning denture and/or eating problems, the present state of health, psychological and physical wellbeing, life satisfaction, and QOL was developed. To discuss the validity and reliability of the questionnaire, 48 outpatients who wore a denture were asked to fill it out. Next, to discuss the difference in QOL of the patient with various kinds of dentures and conditions, 103 outpatients were asked to complete the newly developed questionnaire. The questionnaire which contained four factor areas with eight questions for denture patients was developed by factor analysis with Varimax rotation. The reliability of the QOL scale was confirmed by reliability analysis (Cronbach's alpha = 0.784). The QOL score of edentulous patients with a complete denture having some trouble chewing was significantly lower than that of other denture patients. It was suggested that the wearing of a denture significantly affected the QOL of elderly persons.

Association in Japanese patients between neuroleptic malignant syndrome and functional polymorphisms of the dopamine D(2) receptor gene.

A genetic predisposition to the development of neuroleptic malignant syndrome (NMS) has been suggested by clinical studies. Although the molecular basis of NMS is unclear, a dopaminergic blockade mechanism has been considered the main cause. We therefore investigated the association between NMS and three functional polymorphisms of the dopamine D(2) receptor (DRD(2)) gene: TaqI A, -141C Ins/Del, and Ser311Cys. Subjects included 32 Japanese patients, previously diagnosed with NMS, and 132 schizophrenic patients treated with neuroleptics without occurrence of NMS. Polymerase chain reaction and restriction fragment length polymorphism analyses were performed to determine each genotype. We found significant differences in genotypic and allelic frequencies of the -141C Ins/Del polymorphism between patients with and without NMS. The -141C Del allele was significantly more frequent in the NMS group (23.4 vs 11.7%, P=0.026). Similarly, the proportion of -141C Del allele carriers was significantly higher in the NMS group (40.6 vs 20.5%, P=0.022). No significant differences between the two groups were seen for allelic and genotypic frequencies of the TaqI A and Ser311Cys polymorphisms. This result suggests that the -141C Ins/Del polymorphism is likely to predispose toward the development of NMS, probably together with other unidentified factors.

Clinical implications of cardiac (123)I-meta-iodobenzylguanidine scintigraphy and cardiac natriuretic peptides in patients with heart disease.

The purpose of this study was to evaluate whether or not cardiac sympathetic nerve activity, using (123)I-meta-iodobenzylguanidine ((123)I-MIBG) imaging, and cardiac natriuretic peptides (atrial and brain, ANP and BNP) were independent predictors of cardiac events, and, if so, which was the stronger predictor. Planar (123)I-MIBG images were obtained from 62 patients with heart disease. Plasma ANP and BNP levels, left ventricular ejection fraction (LVEF) by echocardiography, serum total cholesterol and triglyceride were measured. (123)I-MIBG was assessed as the heart-to-mediastinum (H/M) ratio of the delayed image and the washout rate (WoR) from the early to the delayed image. Patients were followed up for an average of 16.2 months, and 12 of 62 patients had cardiac events. Patients with events had significantly lower LVEF and H/M ratio compared with those without events. They had significantly higher WoR, ANP and BNP. By multivariate Cox proportional hazard analysis, (123)I-MIBG (H/M or WoR), ANP and BNP were independent predictors for cardiac events. Event-free survival using a Kaplan-Meier model, with a threshold value of 2.0 for H/M and 45% for WoR, showed that patients with H/M<2.0 and/or WoR>45% had a significantly poorer prognosis. These results suggest that (123)I-MIBG imaging and cardiac natriuretic peptides are useful tools for the evaluation of patients with heart disease, and that cardiac sympathetic nerve activity is a stronger predictor of cardiac events.

Scintigraphic evaluation of chronic osteomyelitis of the mandible in SAPHO syndrome.

A patient with SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis and osteitis) was evaluated by combined scintigraphy. (99m)Tc HMDP scintigraphy showed accumulation in the sternum and lumbar vertebrae as well as the right mandible, whereas (67)Ga citrate showed an accumulation in the right mandible, but not in the sternum or lumbar vertebrae. These results are consistent with chronic osteomyelitis in the mandible.

Regulatory effects of senescence marker protein 30 on the proliferation of hepatocytes.

Senescence marker protein 30 (SMP 30) is preferentially expressed in the liver. One of its remarkable functions is the protection of cells against various injuries by enhancement of membrane calcium-pump activity. We analyzed the role of SMP 30 in hepatocyte proliferation. SMP 30 expression was decreased initially, then increased along with hepatic regeneration, after carbon tetrachloride (CCl4) administration. SMP 30 expression was decreased in the necrotic phase and then gradually increased. Its increase was slightly delayed just after the mitotic phase. These results lead us to speculate that mitoses of hepatic cells induce enhanced SMP 30 expression. In contrast, administration of lead nitrate (LN) as a hepatic mitogen induced a more stable increase of SMP 30 expression. To estimate the effect of SMP 30 on cell proliferation, we evaluated hepatic mitosis in wild-type and SMP 30-deficient knockout (KO) mice after CCl4 administration. We found an increase in mitotic numbers in hepatocytes of KO mice. This result suggests that SMP 30 has a suppressive effect on cell proliferation. Suppressive activity of SMP 30 cDNA was shown in cultured hepatoblastic cells. Our results suggest that SMP 30 performs a regulatory function in liver regeneration.

Linkage disequilibrium and haplotype analysis among eight novel single-nucleotide polymorphisms in the human tissue-type plasminogen activator (t-PA) gene.

Tissue-type plasminogen activator (t-PA), a serine protease, activates the conversion of plasminogen to the fibrinolytic protein, plasmin. The t-PA gene, mapped to chromosome 8p12-p11.2, contains 14 exons. An Alu insertion/deletion (I/D) polymorphism in this gene has been associated with an increased risk for myocardial infarction. In the work reported here we sequenced 11 kilobases (kb) of genomic DNA from 50 normal Japanese volunteers (100 alleles), to include all 14 exons of the t-PA gene, flanking intronic sequences, and 6kb of the 5' sequence. These experiments identified eight novel single-nucleotide polymorphisms (SNPs), in addition to the known Alu I/D polymorphism, from which genotypic data we constructed 12 haplotypes in the tested population. Two-way comparisons of SNPs and the Alu polymorphism revealed strong linkage disequilibrium between the Alu site and SNPs at positions 20,209 (chi2 = 92.263) and 27,555 (chi2 = 47.53), and between SNPs at positions 27,849 and 28,902 chi2 = 66.331). A phylogenic tree was constructed to infer a process of genome construction that would reflect the sequence variations we observed. Our results help to explain the lack of agreement among results of various disease-association studies in which a contribution of the human t-PA gene has been suspected but not always confirmed.

Germline mutations of the PTCH gene in Japanese patients with nevoid basal cell carcinoma syndrome.

Nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant disorder characterized by developmental and skeletal anomalies, palmo-plantar pits, odontogenic keratocysts, ectopic calcification, and occurrence of various types of tumors including basal cell carcinoma. Recent evidence has indicated that the human homologue of a Drosophila segment polarity gene, PTCH, is a NBCCS susceptibility gene. In the study presented here, we detected two novel mutations of the PTCH gene, I805X/2395delC and Y93X/C297A, in two unrelated Japanese patients. Early protection of the skin from the sunlight is important to the prevention of BCC development in NBCCS patients. Genetic analysis of the PTCH gene is essential for the early, definitive diagnosis of NBCCS, especially before the expression of clinical manifestations is complete.

The down-regulation of glutathione peroxidase causes bovine luteal cell apoptosis during structural luteolysis.

Prostaglandin (PG) F(2)a is known to initiate luteal cell apoptosis in the bovine corpus luteum (CL) via its specific receptor (FP) on the luteal membrane by inducing intracellular Ca(2+) mobilization and the activation of PKC. In order to identify the signaling components involved in cell apoptosis, mRNA levels and activities of antioxidative enzymes were analyzed using bovine CL at different stages of the estrous cycle. Northern blot analysis revealed that the levels of two isozymes of superoxide dismutase (SOD), the Mn and Cu/Zn types, and catalase are highly enriched in the middle estrous phase, whereas glutathione peroxidase (GPx) levels gradually decrease as the estrous cycle progresses. The incubation of bovine luteal cells with H(2)O(2) and mercaptosuccinate (MS), a specific inhibitor of GPx, resulted in an increase in chromatin DNA condensation and apoptotic DNA fragmentation. Analyses of the enzymatic activities of GPx and catalase support the RNA data, indicating that H(2)O(2) produced due to the lack of GPx is a potent inducer of luteal cell apoptosis.