Masato Narita

The F(ab')2 fragment of an Aβ-specific monoclonal antibody reduces Aβ deposits in the brain

Abstract This work examines whether administering the F(ab´) 2 fragment of an IgG1 monoclonal antibody (mAb) targeting the N-terminal 1–13 amino acids of the β-amyloid peptide (Aβ mAb) reduces amyloid deposition in Alzheimers disease (AD). The F(ab′) 2 fragment was injected intraperitoneally or intracranially into Tg2576 mice, a murine model of human AD. Both routes of administration significantly reduced Aβ plaque formation in the brain, as determined immunohistochemically and by monitoring levels of Aβ 1–40 and Aβ 1–42 peptide. Use of the F(ab′) 2 fragment significantly reduced phagocytic infiltration in the CNS when compared to intact mAb. Since IgG1 Abs do not fix complement, these findings suggest that effective in vivo clearance of amyloid deposits can be achieved without stimulation of FcR-reactive phagocytes or activation of the complement cascade.

Antimicrobial Susceptibility of Microorganisms Isolated from Periapical Periodontitis Lesions.

Periapical periodontitis usually results from microbial infection, with these microorganisms occasionally migrating to the root canal, which can lead to further, potentially life-threatening, complications. Here, the susceptibility of 27 bacterial strains to various antimicrobial agents was evaluated. These strains comprised 13 species; 16 of the strains were clinical isolates from periapical lesions. Each strain was inoculated onto blood agar plates containing one of the antimicrobial agents. The plates were incubated anaerobically at 37°C for 96 hr and the minimal inhibitory concentrations (MICs) determined. Ten strains required an MIC of 32 μg/ml or greater for amoxicillin, 6 for cefmetazole, and 5 for cefcapene among β-lactam antibiotics; 8 strains required an MIC of 32 μg/ml or greater for clindamycin, 4 for azithromycin, and 11 for clarithromycin among macrolide antibiotics; 3 strains required an MIC of 32 μg/ml or greater for ciprofloxacin and 2 for ofloxacin among fluoroquinolones. The effect of cefcapene on 5 strains was evaluated after biofilm formation to investigate the relationship between biofilm formation and susceptibility. All strains showed a decrease in susceptibility after biofilm formation. The results revealed that several antimicrobial agents commonly used in a clinical setting, including amoxicillin, cefmetazole, and clindamycin, are potentially effective in the treatment of orofacial odontogenic infections. The development of resistant strains, however, means that this can no longer be guaranteed. In addition, azithromycin, ciprofloxacin, and ofloxacin were more effective than the 3 β-lactam antibiotics tested. These results suggest that sensitivity testing is needed if odontogenic infections are to be treated safely and effectively.

Congenital Epulis: A Case and Review of the Literature

Congenital epulis is an unusual benign oral mucosal lesion in newborns with no tendency to recur after excision. The histogenesis of the lesion is unknown, but it is believed to be of mesenchymal origin. We describe a case of congenital epulis (20×10 mm) in the mandibular gingiva of a newborn. The mass, which was smooth-surfaced and pedunculated with a healthy color, was surgically removed at 5 months post-birth. Histologically, the tumor consisted mainly of large eosinophilic granular cells. Immunohistochemical studies revealed intense staining for vimentin, STRO-1, and CD44, suggesting that it was derived from mesenchymal cells. The literature and immunohistochemical profile of congenital epulis are also discussed.

Our Team’s Safety Management of the Sagittal Splitting Method of the Mandibular Ramus

Orthognathic surgery is performed for congenital anomalies, growth of jaw abnormalities, and tumor and trauma after jaw treatment. The sagittal splitting method of the mandibular ramus is performed most commonly in the world, but resulting complications are increasing. The sagittal procedure and perioperative care have been established, however, complications of orthognathic surgery have been reported in many hospitals. Therefore, we should perform the surgery safely, with careful consideration, and eventually we need to improve the surgery. Our treatment goal is to improve the facial form and to attain appropriate occlusion. Accordingly, we need to understand the patients background as a useful reference for drawing up the treatment plan. This paper reports on a safe sagittal splitting method of the mandibular ramus performed by our team.

Prenatal Counseling on Prenatal Diagnosis of Cleft Lip and/or Cleft Palate at Tokyo Dental College Ichikawa General Hospital

Remarkable technological advances have been made in the field of medicine in recent years, one result of which is that a prenatal diagnosis of cleft lip and/or cleft palate (CL/P) is now possible. In this situation, it is extremely important to provide the parents with mental care from the moment they are informed. Here, we describe cases of CL/P treated at our hospital and how such a diagnosis and prenatal counseling are handled. A survey was carried out on 4 cases seen at our department between April 2013 and March 2014. Patients are referred to our department from local or our own obstetrics clinics on a prenatal diagnosis of CL/P based on findings from ultrasonography. If the case is a referral from outside, the patient will first be seen at our own obstetrics department. Our department may then be subsequently requested to provide the parents with prenatal counseling. Effort is made to reassure the parents that postnatal support will be provided, right from the start. Next, the multidisciplinary nature of the treatment process is explained. However, only the essential outline is given at first so as to avoid inducing unnecessary anxiety. A response is also given to any questions the parents may have. Our experience of giving such care leads us to believe that improvements are required in the way that explanations and assistance are provided. The number of cases in which prenatal counseling is required is expected to increase in future.