The dual origin of the peripheral olfactory system: placode and neural crest

<p>Abstract</p> <p>Background</p> <p>The olfactory epithelium (OE) has a unique capacity for continuous neurogenesis, extending axons to the olfactory bulb with the assistance of olfactory ensheathing cells (OECs). The OE and OECs have been believed to develop solely from the olfactory placode, while the neural crest (NC) cells have been believed to contribute only the underlying structural elements of the olfactory system. In order to further elucidate the role of NC cells in olfactory development, we examined the olfactory system in the transgenic mice Wnt1-Cre/Floxed-EGFP and P0-Cre/Floxed-EGFP, in which migrating NC cells and its descendents permanently express GFP, and conducted transposon-mediated cell lineage tracing studies in chick embryos.</p> <p>Results</p> <p>Examination of these transgenic mice revealed GFP-positive cells in the OE, demonstrating that NC-derived cells give rise to OE cells with morphologic and antigenic properties identical to placode-derived cells. OECs were also positive for GFP, confirming their NC origin. Cell lineage tracing studies performed in chick embryos confirmed the migration of NC cells into the OE. Furthermore, spheres cultured from the dissociated cells of the olfactory mucosa demonstrated self-renewal and trilineage differentiation capacities (neurons, glial cells, and myofibroblasts), demonstrating the presence of NC progenitors in the olfactory mucosa.</p> <p>Conclusion</p> <p>Our data demonstrates that the NC plays a larger role in the development of the olfactory system than previously believed, and suggests that NC-derived cells may in part be responsible for the remarkable capacity of the OE for neurogenesis and regeneration.</p

Neurocognitive Evaluation of Japanese Childhood Cancer Survivors

Long-term cognitive effects following acute lymphoblastic leukemia treatment have been reported for Caucasians; however, these data remain unclear for other ethnicities and the treatment of other cancers. Here, we assessed cognitive function in Japanese childhood cancer survivors. This study enrolled 53 Japanese survivors of childhood cancer （mean age, 9.5 years; 36 boys and 17 girls）. We evaluated performance-based cognitive function using the Wechsler Intelligence Scale for Children-Fourth Edition （WISC-Ⅳ）. Deviation intelligence quotients （IQ） for verbal comprehension （VC）, perceptual reasoning （PR）, processing speed （PS）, and working memory （WM） were compared with the standardized mean and standard deviation （SD; 100 and 15, respectively）. We classified patients into three groups depending on the cumulative methotrexate （MTX） dose （none, 1–19g/m2, and＞20g/m2）. Full-scale IQ was within normal range at 104.8 （SD, 12.9）, although there were significant differences among the four WISC–Ⅳ index scores （P＜0.001）. The PS score （97.1±15.5） was significantly lower than the VC （107.2±15.8） and PR （105.3±14.2） scores （both P＜0.005）. WM performance decreased in an MTX dose-dependent manner （107.8, 102.6, and 96.5 for none, 1–19g/m2, and higher than 20g/m2, respectively; P=0.05）. Japanese childhood cancer survivors, including those in the non-MTX group, demonstrated significant PS impairment. High-dose MTX treatment might be associated with neurocognitive deficiencies, particularly in WM. Although current treatments are associated with high cure rates, future research and interventions are required to improve cognitive function in these patients

Identification of biomarkers in ductal carcinoma in situ of the breast with microinvasion

<p>Abstract</p> <p>Background</p> <p>Widespread use of mammography in breast cancer screening has led to the identification of increasing numbers of patients with ductal carcinoma <it>in situ </it>(DCIS). DCIS of the breast with an area of focal invasion 1 mm or less in diameter is defined as DCIS with microinvasion, DCIS-Mi. Identification of biological differences between DCIS and DCIS-Mi may aid in understanding of the nature and causes of the progression of DCIS to invasiveness.</p> <p>Methods</p> <p>In this study, using resected breast cancer tissues, we compared pure DCIS (52 cases) and DCIS-Mi (28 cases) with regard to pathological findings of intraductal lesions, biological factors, apoptosis-related protein expression, and proliferative capacity through the use of immunohistochemistry and the TdT-mediated dUTP-biotin nick end labeling (TUNEL) method.</p> <p>Results</p> <p>There were no differences in biological factors between DCIS and DCIS-Mi, with respect to levels of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor type 2. The frequency of necrosis and positive expression ratio of survivin and Bax were significantly higher in DCIS-Mi than in DCIS. In addition, apoptotic index, Ki-67 index, and positive Bcl-2 immunolabeling tended to be higher in DCIS-Mi than in DCIS. Multivariate analysis revealed that the presence of necrosis and positive survivin expression were independent factors associated with invasion.</p> <p>Conclusion</p> <p>Compared with DCIS, DCIS-Mi is characterized by a slightly elevated cell proliferation capacity and enhanced apoptosis within the intraductal lesion, both of which are thought to promote the formation of cell necrotic foci. Furthermore, the differential expression of survivin may serve in deciding the response to therapy and may have some prognostic significance.</p

Event-based surveillance in north-western Ethiopia: experience and lessons learnt in the field

This study piloted an event-based surveillance system at the health centre (HC) level in Ethiopia. The system collects rumours in the community and registers them in rumour logbooks to record events of disease outbreaks and public health emergencies. Descriptive analysis was conducted on the events captured at the 59 study HCs in the Amhara Region in north-western Ethiopia between October 2013 and November 2014. A total of 126 rumours were registered at two thirds of the HCs during the study period. The average event reporting time was 3.8 days; response time of the HCs was 0.6 days, resulting in a total response time of 4.4 days. The most commonly reported rumours were measles-related (n = 90, 71%). These rumours followed a similar pattern of measles cases reported in the routine surveillance system. The largest proportion of rumours were reported by community members (n = 38, 36%) followed by health post workers (n = 36, 29%) who were normally informed by the community members about the rumours. This surveillance system was established along with an existing indicator-based surveillance system and was simple to implement. The implementation cost was minimal, requiring only printing and distribution of rumour logbooks to the HCs and brief orientations to focal persons. In countries where routine surveillance is still weak, an event-based surveillance system similar to this should be considered as a supplementary tool for disease monitoring

Myoepithelial Carcinoma of the Breast Treated with Surgery and Chemotherapy

Myoepithelial carcinoma (malignant myoepithelioma) of the breast is a rare tumor, for which only a limited number of reports have been published. Most of the reports emphasized diagnosis and pathology but not biological behavior and treatment. We report a 61-year-old patient with breast myoepithelial carcinoma who developed locoregional and distant metastases and received many chemotherapy regimens. She presented with an elastic hard mass of the left breast. Breast conserving surgery was performed as part of both diagnosis and treatment. From the results of histological and immunohistochemical examinations, this case was considered to be a myoepithelial carcinoma. Fifteen months after the completion of adjuvant radiotherapy, distant metastasis of the left parasternal lymph node metastasis developed. She was treated by further excision and received a total of four regimens of chemotherapy including a combination of doxorubicin and cyclophosphamide. She received chemotherapy for 20 months after the diagnosis of metastasis