Effectiveness and fabrication of mouthguards

Abstract –  Although mouthguards have been suggested as a means for preventing dental traumatic injuries, there are still some controversies over some aspects such as effectiveness in preventing concussions, material selections, method for fabrication, design, side effects and so on. The purpose of this literature review was to clarify differences in opinions with supporting evidence on these issues and find the best guidelines for promoting usage and providing mouthguards with better protective capability and fewer side effects such as difficulty in breathing and speaking.     

Enhanced Percolation and Gene Expression in Tumor Hypoxia by PEGylated Polyplex Micelles

In regard to gene vectors for cancer gene therapy, their percolation into the tumor tissue should be essential for successful outcome. Here, we studied the tumor penetrability of nonviral vectors (polyplexes) after incubation with the multicellular tumor spheroid (MCTS) models and intratumoral (i.t.) injection into subcutaneous tumors. As a result, polyethylene glycolated (PEGylated), core–shell type polyplexes (polyplex micelles) showed facilitated percolation and improved transfection inside the tumor tissue, whereas conventional polyplexes from cationic polymers exhibited limited percolation and localized transfection. Furthermore, the transfection of hypoxia-responsive plasmid demonstrated that polyplex micelles allowed the transfection to the hypoxic region of the tumor tissue in both in vitro and in vivo experiments. To the best of our knowledge, our results demonstrated for the first time that polyplex micelles might show improved tumor penetrability over cationic polyplexes, thereby achieving transfection into the inside of the tumor tissue.     

Development of packaging cell lines for generation of adeno-associated virus vectors by lentiviral gene transfer of trans-complementary components

Adeno-associated virus (AAV) vector system has several useful advantages with regard to in vitro and in vivo gene transfer. However, their usages have been limited by cumbersome and labor-intensive vector production in the traditional method. To overcome limitations in AAV production, in this report, we explored the possibility of generating AAV packaging cell line, 293T R/C.VA.E2A.E4. cells, by using lentivirus-mediated transduction of Rep/Cap gene of AAV-2, VA RNA, E2A, and E4 genes of Ad5 into 293T cells. In packaging cell lines, it is important that supply of the AAV vector can be stably performed for long time. We showed that the 293T R/C.VA.E2A.E4. cells have stably maintained the transduced components after more than 10 passages and yielded high-titer AAV vectors, and the titer of AAV vectors did not decline even if culture of the packaging cells was continued for long time. The Rep/Cap and E4 gene products caused no remarkable cytotoxicity. The 293T R/C.VA.E2A.E4. cells might be able to tolerate the Rep/Cap and E4 gene products, or have less copy numbers of the Rep/Cap and E4 genes than the traditional method. Moreover, we showed that the AAV vectors derived from 293T R/C.VA.E2A.E4. cells infected the primary human CD34+ haematopoietic progenitor cells with high efficiency (50-70%). In the 293T R/C.VA.E2A.E4. cells, the AAV vectors can be generated by the transfection of one AAV vector plasmid, and large-scale AAV production can be easily achieved. It is important that cumbersome, variable, and costly transfection is avoided.     

Three adult cases with Corynebacterium propinquum respiratory infections in a community hospital

Corynebacterium propinquum, which is included in Corynebacterium group ANF-3, exists as a commensal in the oral flora. This organism has not yet been fully recognized as a respiratory pathogen. We previously reported that the first case with respiratory infection caused by C. propinquum. On the other hand, Corynebacterium pseudodiphtheriticum is recognized as a causative organism in respiratory infections. Recently we experienced two cases with C. propinquum respiratory infections in our hospital. Three types of the onset such as a community-acquired infection, a hospital-acquired infection, and a nursing home acquired infections were observed. Our analysis indicated that gram staining of the purulent sputum is an essential tool to evaluate whether C. propinquum is a respiratory pathogen or not, because this organism is a commensal bacteria.     

Results of a survey of community-acquired-pneumonia and evaluation of old and new Japanese Respiratory Society guidelines]

We evaluated the usefulness of domestic and foreign guidelines for the diagnosis and treatment of patients with community-acquired-pneumonia at 23 institutions in 6 prefectures of the Tohoku Area, from December 2003 to November 2004. Based on the old and new Japanese Respiratory Society (JRS) guidelines, we evaluated severity, clinical efficacy and detection of atypical pneumonia. As for severity, the old guidelines led to the diagnosis of an excessive number of 'severe' cases. On the other hand, patients were appropriately diagnosed as having mild, moderate, severe, or very severe disease based on the new JRS guidelines (2005). The severity classification often correlated with the Pneumonia Severity Index (PSI) of the IDSA guidelines. The efficacy rate for patients who were prescribed the recommended drug according to the old JRS guidelines was 85.7% and for those who did not use the recommended drug it was 68.7% (p < 0.001).     

Mondini dysplasia with recurrent bacterial meningitis caused by three different pathogens

Mondini dysplasia is rare, but has an important association with recurrent bacterial meningitis. We herein describe the case of a 3‐year‐old girl with unilateral sensorineural hearing loss who presented with three independent episodes of bacterial meningitis within 8 months. Temporal bone computed tomography indicated the characteristic features of Mondini dysplasia in the right inner ear. This was treated by surgical closure of the inner ear defect via oval window and additional vaccination was administered. Appropriate vaccination might prevent the recurrent bacterial meningitis associated with Mondini dysplasia.