Background: Poly(acrylic acid) (PAA) is a water-soluble synthetic polymer with tissue-adhesive properties. When PAA is mixed with polyvinylpyrrolidone (PVP) in water, it forms a water-insoluble precipitate that neither swells nor adheres to tissues. Methods and Results: We developed a novel solid/solution interface complexation method to obtain a water-swellable PAA/PVP complex. First, PAA solution was dried up in a vessel to form a film. The PAA film was then immersed in an aqueous PVP solution to obtain a highly swollen PAA/PVP hydrogel. Heat drying of the hydrogel yielded a transparent film, while freeze-drying the hydrogel provided a soft sponge. Both the PAA/PVP film and sponge could be re-swelled by water to obtain a bioadhesive gel. A relatively larger specific surface area of the sponge than that of the film led to a more rapid swelling and water absorption behavior and quick adhesion to tissues. The addition of hyaluronic acid (HA) improved the mechanical characteristics of the sponges. PAA/PVP/HA sponges had low cytotoxicity, and they exhibited high hemostatic efficiency in clinical studies after dialysis treatment or tooth extraction, even in patients on antithrombotic drugs. Conclusions: Such bioadhesive materials consisting of low-toxicity polymers have a high potential for use in medical hemostatic devices.

Poly(acrylic acid) (PAA) is a water-soluble synthetic polymer that exhibits bioadhesive properties and has been applied in various novel medical devices, such as drug-delivery carriers and hemostatic agents. PAA forms a water-insoluble complex when mixed with polyvinylpyrrolidone (PVP). If PAA and PVP are mixed in water, they form an aggregated precipitate, which neither swells nor adheres to tissues. The formation of the hydrophobic complex was caused by hydrophobic interactions between the main chains of both polymers aligned the same as a zipper. To hinder the zipper-like alignment of the polymer main chains, hyaluronic acid (HA), a macromolecular viscous polysaccharide, was added to the PVP solution prior to complex formation. When the initial concentration of PAA was lower than 0.05%, HA effectively prevented the aggregation of PAA/PVP complexes and resulted in a slightly clouded suspension. Freeze-drying of the mixture yielded a soft white sponge, which could immediately swell in water to form a highly bioadhesive hydrogel. The PAA/PVP complex prepared with HA exhibited high hemostatic efficiency in clinical studies, even in patients on antithrombotic drugs.

Cowden's disease is an autosomal dominant disorder caused by mutation of the phosphatase and tensin homologue deleted on chromosome 10 (PTEN). Cowden's disease is characterized by symptoms such as hamartomas developing in multiple organs, papillomatous hyperplasia, and papules on the face or limbs. We describe a 69-year-old woman with a chief complaint of gingival swelling who was found to have multiple papillomatous hyperplastic lesions of the maxillary and mandibular gingiva within the oral cavity and small papules on the skin of the neck. Upper gastrointestinal endoscopy revealed multiple polyps in the esophagus and stomach. Cowden's disease was diagnosed after detection of the PTEN mutation on genetic analysis. Caution is required in differential diagnosis when multiple papillomatous papules are present within the oral cavity, because this could be an oral symptom of a disorder such as Cowden's disease.

We used high- (ACCM) and low- (ACC2) metastasis cell lines of human adenoid cystic carcinoma (ACC) as an experimental model to study metastatic mechanisms and compare their expression levels for angiogenic-related factor vascular endothelial growth factor (VEGF). By using a series of extensive analyses, hypoxia-inducible factor-1 (HIF-1) α-dependent VEGF expression levels were observed to be higher in ACCM cell lines, increasing the possible development of tumor metastasis, compared to ACC2 cell lines. Our findings provide the novel insight that HIF-1α-dependent VEGF overexpression under hypoxic conditions shows to some extent associations with the metastatic tendency of ACC cells and may function as a potential target for ACC therapy.

Salivary duct carcinoma (SDC) is regarded as high-grade malignancy with accompanied by bone destruction originating in the ductal epithelium of salivary gland. SDC arising in the minor salivary gland of the oral cavity is very rare. We present here a single case of SDC arising from the minor salivary gland of a 82-year-old man. His first symptom was swelling on the left side of the palate. There is no bone resorption by the results of imaging studies, so benign tumor located in minor salivary gland was suspected. The tumor was dissected surgically and the intraductal component is microscopically described as a cribriform, papillary, solid growth pattern, with central necrosis. Immunohistochemical staining of intraductal component cells was positive for human epidermal growth factor receptor type2 (Her2), gross cystic disease fluid protein-15 (GCDFP-15) and androgen receptor (AR). As a result, the tumor was diagnosed as a SDC.

microRNAs (miRNAs) are involved in cancer pathogenesis, apoptosis and cell growth, thereby functioning as both tumor suppressors and oncogenes. However, the expression patterns and roles of miRNAs in oral squamous cell carcinoma (OSCC) remain largely unknown. We hypothesized that oral cancer may have a unique miRNA profile, which in turn may play a critical role in oral cancer development, progression, diagnosis and prognosis. We, therefore, investigated the expression profiles of 29 OSCC tumors and 7 normal oral mucosal samples. The miRNA expression patterns in OSCC were examined by Taq Man-based microRNA assays. We were subsequently able to identify the candidates of cancer-related miRNAs through analysis of the miRNA expression profiles. In conclusion, OSCC tissues were shown to have a unique miRNA profile pattern when compared with that in normal tissues. The present study may provide useful information for further investigation of the functional roles of miRNAs in OSCC development, progression, diagnosis and prognosis.

昭和大学歯科病院では2007年10月より, 口腔外科外来において口腔粘膜などに不安をもつ人を対象とした口腔がん無料相談を開始した. 予約制で毎週土曜日に相談を受けた. 今回, 2007年10月から2011年9月までの4年間に相談目的に当院へ来院した264名に対して, 年度別・性別・年齢別相談者数, および臨床診断, 相談者の居住地域, 口腔がん無料相談を知った媒体に関して検討を行ったので報告する. 1年間の相談患者数は平均66名であり, 臨床診断としては, 口内炎が最も多く, 次いで白板症, 良性腫瘍, 口蓋・下顎隆起, 歯科疾患と続き, 新たに2名の口腔がん患者を発見した.

AIM Enhancer of zeste homolog-2 (EZH2) and B lymphoma Mo-MLV insertion region-1 homolog (BMI1) are members of the polycomb group of proteins, which function as transcriptional repressors through chromatin modification. EZH2 forms part of the polycomb repressive complex (PRC)-2, while BMI1 is a component of PRC1. Previous studies have shown that EZH2 is highly expressed in various type of cancers. Expression of EZH2 is reported to be regulated by the P53-E2F/retinoblastoma (RB)-related pathway, and a correlation between P53 mutation and EZH2 expression was recently found in breast cancer. Here, we examined the relationship between P53 and EZH2 in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS Using immunohistochemistry, we investigated the expression of EZH2 and BMI1 in 99 surgically-resected OSCC and 34 epithelial dysplasia samples. We analyzed associations between aberrant expression of EZH2 and BMI1, and clinicopathological findings and patient outcome. P53 expression was also examined and analyzed in relation to EZH2 and BMI1 expression. RESULTS EZH2 and BMI1 protein were up-regulated in OSCC tissues compared with epithelial dysplasia and normal epithelium. Aberrant EZH2 and BMI1 protein expression was observed in 32 and 59 of the 99 OSCC samples, respectively. Aberrant EZH2 and BMI1 expression was significantly associated with mode of invasion, but not with lymph node metastasis or survival rate. Aberrant EZH2 expression was associated with P53 alteration in OSCC tissue. Expression of EZH2 mRNA in SAS/neo cells, which have wild-type P53, was significantly lower than in SAS/mp53 cells that have a mutant P53 gene. CONCLUSION P53 alteration may be involved in dysregulated EZH2 expression, and aberrant expression of EZH2 may play a role in carcinogenesis of OSCC.

昭和大学歯科病院では平日夜間および土曜の午後1時から夜間, 日曜および祝日の終日は時間外受診患者に対しての対応を行っている. 当院は, 近隣の城南地区や川崎市からの受診患者が多く, 同地区においては平日夜間および日曜・祝日に対応可能な病院歯科・口腔外科が少ないという特徴がある. 今回, 平成17年1月から平成21年12月までの5年間に当院を時間外受診した患者1,612人に対して, 年度別・月別・受診時間別・性別・年齢別受診患者数, および受診理由, 治療内容等に関して臨床統計を行ったので報告する. 1年間の時間外受診平均患者数は約300人であり, 受診理由としては疼痛を主訴としたものが最も多く, 次いで外傷, 出血, 顎関節脱臼と続き, 疼痛と外傷を合わせて全体の約半分を占めていた. また当院の特徴として補綴物, 仮封材の脱離による受診も約20%と比較的多くみられた. 受診年齢としては10 歳未満と20 歳代の患者が多い傾向が見られた．さらに，当院と同様に歯科のみの診療科で，時間外受診患者の対応を行っている歯学部附属病院および歯科診療所の疾患別受診患者数および診療体制を含めた報告と当院における統計を比較検討した．