Biomedical subjects

M Ohyama

Publications and source records attributed to M Ohyama.

185 records · Page 11Linked to original sources

PubMedDate not supplied

Color electromyographic topographic analysis of facial movements.

To determine the precise amount of facial function present in patients with facial palsy, color electromyographic (EMG) topograms of the facial movements were made using a computerized system, newly designed and manufactured by the authors. During mimetic movements, such as wrinkling the forehead, closing the eyes, blinking, grinning, and blowing out the cheeks, EMGs from 16 monopolar disk electrodes were concurrently recorded from the frontalis, orbicularis oculi, and orbicularis oris muscles on both sides. The amplitude values of the integrated EMG spikes from each electrode were calculated by an interpolation formula in the computer, and the color topographic figures derived from these calculations were displayed on a ten-color computer monitor. The colors ranged from blue to dark red, and they were related to the amount of muscular activity. This technique was applied to patients with facial palsy to document their degree of mimetic movement loss and the time course of the palsy evolution. The results obtained were reliable and reproducible, and the technique made it easy to quantify the loss of mimetic movements in patients with facial palsy.

Adult↗

PubMedDate not supplied

Assessment of p53 protein expression in normal mucosa and benign and malignant lesions of the nasal cavity.

p53 gene mutation is documented in head and neck cancer. No reports exist relating this mutation to normal mucosa or benign and malignant lesions of the nasal cavity. We investigate p53 overexpression using immunohistochemical techniques improved by an antigen retrieval method. p53 protein was analyzed in the following cases: normal, benign [papilloma and inverted papilloma (IP)] and malignant [squamous-cell carcinoma (SCC) arising in IP, SCC alone, adenocarcinoma and small-cell carcinoma]. Both the intensity and rate of positive p53 immunostaining were evaluated using a quantitative Auto-CAD program. Overexpression of p53 protein was not identified in normal mucosa, benign or premalignant lesions; however, approximately 60% is correlated to nasal cancer. p53 overexpression correlates with heavy smoking. Both the IP and SCC portions of SCC synchronous with IP showed similar p53 immunoreactivity. SCC arising in IP shows a lower p53 immunoreactivity than SCC alone. Thus, smoking along with a p53 mutation may be a mutagenic agent in nasal cancers. Alteration of the p53 protein may play an important role in the early stages of the malignant transformation of IP. A low p53 immunoreactivity indicates the presence of wild-type p53 protein. This may show a better response to radiation therapy yielding a better prognosis for SCC arising in IP compared to SCC alone. However, further clinical trials are required to investigate this possibly worthwhile prognostic marker.

Adult↗

PubMedDate not supplied

Analysis of glycoproteins from nasal polyps and papillomas by affinity chromatography.

Glycoproteins were isolated from the particulate fraction of four nasal polyps and three nasal papillomas by affinity chromatography on lectins conjugated with agarose (Concanavalin A [Con A], wheat germ agglutinin [WGA], Ricinus communis agglutinin [RCA], peanut agglutinin [PNA], and Dolichos biflorus agglutinin [DBA]). The glycoprotein mixtures so isolated were then analyzed by sodium dodecyl sulfate gel electrophoresis. Glycoprotein profiles of nasal polyps were similar to each other, but were distinctively different from those of nasal papillomas. Binding sites for Con A, WGA, and RCA isolated from nasal papillomas contained intense bands with a molecular weight less than 15,000 daltons, which were absent in nasal polyps. The major component of PNA-binding sites of nasal polyps is of a molecular weight of 65,000 daltons, which was not detected in nasal papillomas.

Adult↗

PubMedDate not supplied

Immunohistochemistry of p53 in sinonasal inverted papilloma and associated squamous cell carcinoma.

Gene mutation of p53 is documented in head and neck cancer. No reports exist relating human sinonasal inverted papilloma (IP) and its transformation to squamous cell carcinoma (SCC). Using immunohistochemical techniques improved by an antigen retrieval method, p53 protein was analyzed in the following subjects: 16 IP, 12 SCC arising in IP, and 15 SCC alone subjects. Both the intensity (PI) and rate (PR) of positive p53 immunostaining were evaluated using a quantitative AutoCAD program. We correlated p53 protein expression with clinical features. p53 immunoreactivity is significantly lower in IP than in SCC specimens. Both the IP and SCC portions of IP synchronous SCC subjects showed similar p53 protein expression. SCC arising in IP shows a lower p53 immunoreactivity than SCC alone. Alteration of p53 protein may have an important role in the early stages of IP malignant transformation and prove a potential biomarker for risk assessment. Low p53 immunoreactivity, indicating the presence of a wild-type p53, may correlate with the prognosis for SCC arising in IP. However, further clinical trials are required to investigate this possibly worthwhile prognostic marker.

Adult↗

PubMedDate not supplied

Lectin immunohistochemistry study of nasal inverted papilloma and associated neoplasms.

BACKGROUND: We aimed to investigate the tumor biology of nasal IP and identify the biological characteristics associated with early diagnosis and malignant transformation. MATERIALS AND METHODS: Lectins immunohistochemistry were performed on inverted papilloma (IP), and associated neoplasms. IP synchronized with polyp or squamous cell carcinoma (SCC) and IP metachronized with SCC were analyzed and correlated to clinical information. RESULTS: Canavalia ensiformis (ConA) and Arachis hypogaea (PNA) with neuraminidase pretreatment (NA-PNA) showed similar staining in both the IP and SCC portions of the IP synchronized with SCC. The IP and polyp portions of an IP synchronized polyp had positive NA-PNA staining, while papilloma and polyps alone had negative staining. Strong NA-PNA staining in the IP (transformed to SCC) showed significant differences from IP. CONCLUSION: These biological characteristics define IP as a premalignant neoplasm. NA-PNA staining may be helpful for an early detection of IP. Strong NA-PNA staining in IP may predict malignant transformation.

Adult↗