Imaging of Oral SCC Cells by Raman Micro-Spectroscopy Technique.

We used Raman micro-spectroscopy technique to analyze the molecular changes associated with oral squamous cell carcinoma (SCC) cells in the form of frozen tissue. Previously, Raman micro-spectroscopy technique on human tissue was mainly based on spectral analysis, but we worked on imaging of molecular structure. In this study, we evaluated the distribution of four components at the cell level (about 10 µm) to describe the changes in protein and molecular structures of protein belonging to malignant tissue. We analyzed ten oral SCC samples of five patients without special pretreatments of the use of formaldehyde. We obtained cell level images of the oral SCC cells at various components (peak at 935 cm-1: proline and valine, 1004 cm-1: phenylalanine, 1223 cm-1: nucleic acids, and 1650 cm-1: amide I). These mapping images of SCC cells showed the distribution of nucleic acids in the nuclear areas; meanwhile, proline and valine, phenylalanine, and amide I were detected in the cytoplasm areas of the SCC cells. Furthermore, the peak of amide I in the cancer area shifts to the higher wavenumber side, which indicates the α-helix component may decrease in its relative amounts of protein in the ß-sheet or random coil conformation. Imaging of SCC cells with Raman micro-spectroscopy technique indicated that such a new observation of cancer cells is useful for analyzing the detailed distribution of various molecular conformation within SCC cells.

Cavitation inception pressure and bubble cloud formation due to the backscattering of high-intensity focused ultrasound from a laser-induced bubble.

Cavitation bubble cloud formation due to the backscattering of high-intensity focused ultrasound (HIFU) from a laser-induced bubble in various water temperatures and dissolved oxygen (DO) has been investigated. A laser-induced bubble generated near the geometrical focus of HIFU is utilized to yield intense negative pressure by the backscattering. Optical observation with a high-speed video camera and pressure measurement with a fiber-optic probe hydrophone are conducted simultaneously to understand the forming process of a bubble cloud and corresponding pressure field by the backscattering. Optical observation shows that a bubble cloud grows stepwise forming multiple layers composed of tiny cavitation bubbles, and the cavitation inception position is consistent with the local minimum pressure position simulated with the ghost fluid method. The bubble cloud grows larger in the opposite direction of HIFU propagation, and the absolute value of the cavitation inception pressure decreases with an increase in water temperature. The linear correlation between cavitation inception pressure and water temperature agrees with that given by Vlaisavljevich, Xu, Maxwell, Mancia, Zhang, Lin, Duryea, Sukovich, Hall, Johnsen, and Cain [IEEE Trans. Ultrason. Ferroelectr. Freq. Control 63, 1064-1077 (2016)]. However DO has minor dependence on the cavitation inception pressure when DO is degassed sufficiently. Furthermore, the gas nucleus size that might exist in the experiment has been estimated by using bubble dynamics.

Enzyme histochemical adaptive responses of the medial pterygoid muscle and two heads of the lateral pterygoid muscle to long-term soft diet feeding in growing rabbits.

The aim of the present study was to investigate the histochemical effects of long-term soft diet in the medial pterygoid muscle as well as the two heads of the lateral pterygoid muscles in growing rabbits. Eleven young rabbits were divided into two groups as solid diet (control group; n = 6) or soft diet (soft-diet group; n = 5) groups. After 6 months, muscle fibers from the medial and the two heads of the lateral pterygoid muscles were histochemically defined. In the medial pterygoid muscle, the percentage of the type 1 fiber cross-sectional area to total area was 10.1 ± 2.4% in the control group and 8.3 ± 3.0% in the soft-diet group, respectively. In the soft-diet group, there was a trend toward an increase in the number of type 2A fibers, and toward a decrease in the numbers of type 2B fibers in comparison with the controls. In the two heads of the lateral pterygoid muscle, the percentage of the type 1 fiber cross-sectional area to total area was 8.4 ± 7.5 and 3.3 ± 2.7%, respectively. Compared to that of the control group, the two heads in the soft-diet group showed a trend toward a decrease in the number of type 2A fibers. In addition, type 2B had a tendency to decrease in the number in the inferior head. In conclusion, this study suggests that long-term soft diet leads to adaptations of the pterygoid muscles. Two heads of the lateral pterygoid muscle revealed different adaptation from jaw-closing muscles under soft-diet conditions.

The effects of surfactant on the multiscale structure of bubbly flows.

It is well known that a bubble in contaminated water rises much slower than one in purified water, and the rising velocity in a contaminated system can be less than half that in a purified system. This phenomenon is explained by the so-called Marangoni effect caused by surfactant adsorption on the bubble surface. In other words, while a bubble is rising, there exists a surface concentration distribution of surfactant along the bubble surface because the adsorbed surfactant is swept off from the front part and accumulates in the rear part by advection. Owing to this surfactant accumulation in the rear part, a variation of surface tension appears along the surface and this causes a tangential shear stress on the bubble surface. This shear stress results in the decrease in the rising velocity of the bubble in contaminated liquid. More interestingly, this Marangoni effect influences not only the bubble's rising velocity but also its lateral migration in the presence of mean shear. Together, these influences cause a drastic change of the whole bubbly flow structures. In this paper, we discuss some experimental results related to this drastic change in bubbly flow structure. We show that bubble clustering phenomena are observed in an upward bubbly channel flow under certain conditions of surfactant concentrations. This cluster disappears with an increase in the concentration. We explain this phenomenon by reference to the lift force acting on a bubble in aqueous surfactant solutions. It is shown that the shear-induced lift force acting on a contaminated bubble of 1mm size can be much smaller than that on a clean bubble.

Positive patch test for mercury possibly from exposure to amalgam.

OBJECTIVES: Mercury allergy is a serious health problem. We investigated the relationship between positive patch test for mercury and sources of mercury exposure, indicated by concentrations in biological samples from healthy medical students. METHODS: Patch tests for mercury (Hg-PT) were performed on 580 students. For a group of 55 students with a positive Hg-PT result (Hg-PT(+)) and a reference group of 79 students with a negative Hg-PT result (Hg-PT)(-)), mercury concentrations in urine (Hg-u) and hair (Hg-h) were measured. In our search for environmental indicators of mercury exposure, the level of fish intake and mercurochrome usage were determined using a self-administered questionnaire. The oral cavity was investigated and the numbers of decayed teeth filled with amalgam (NA) were counted by dentists. RESULTS: For the male Hg-PT(+) group, Hg-u and Hg-h were higher than those of a male reference Hg-PT(-) group; Hg-u values obtained in the early morning and after supper were significantly different. Multiple regression analysis with Hg-u as the objective variable among all students showed that increases in the level of fish intake, mercurochrome usage, and the NA independently increased Hg-u measured in the early morning for both gender groups. NA significantly affected Hg-u. CONCLUSIONS: We showed that a higher NA was related to a higher Hg-u measured in the early morning. Therefore, exposure to amalgam may increase Hg-u. It was suggested that Hg-PT(+) might be related to a high Hg-u, and possibly to a high NA.

Occult fractures of articular eminence and glenoid fossa presenting as temporomandibular disorder: a case report.

We report an unusual case of occult fractures of the articular eminence and glenoid fossa due to a previous traffic accident presenting as a temporomandibular disorder. A 24-year-old Japanese man was referred for trismus and pain in the right temporomandibular joint, and was suspected of having temporomandibular disorder. Although the magnetic resonance image did not show displacement of the articular disk, T2-weighted images revealed disruption of the cortical low-intensity line of the right articular eminence. On a computerized tomography (CT) scan, an isolated bone fragment of the right articular eminence was clearly seen, and fractures of the right glenoid fossa and articular eminence were noted. The patient was treated by instructing him not to open his mouth widely and to remain on a soft diet for 4 weeks. A CT examination performed 1 year after the treatment showed complete healing of the fracture in the right articular eminence and glenoid fossa.

Diagnostic significance of FDG-PET and argyrophilic nucleolar organizer regions (AgNORs) in oral squamous cell carcinoma.

Neoadjuvant chemoradiotherapy has played an important role in preserving organs and functions in patients with oral squamous cell carcinoma (SCC). To determine whether further operation after chemoradiotherapy is necessary, accurate evaluation of residual tumour cells after treatment is essential. We investigated the usefulness of regional fluorodeoxyglucose (FDG) uptake in combination with histochemical expression of AgNORs obtained from pretreatment biopsy specimens to assess residual tumours after intraarterial chemoradiotherapy. Standardized uptake value (SUV: pretreatment, pre-SUV; post-treatment, post-SUV) was calculated to determine the changes of FDG uptake in the tumour before and after chemoradiotherapy. Four out of 20 patients with oral SCCs showed residual tumour cells after treatment. Tumours with higher post-SUVs (> or =4.0) and higher AgNORs scores (> or =5.0) had significantly higher incidences of residual viable tumour cells after chemoradiotherapy (P=0.001). The results suggest that the combination of FDG-PET with AgNORs score is an excellent index for determining the optimal management of each patient following neoadjuvant chemoradiotherapy.

Preoperative assessment of the relationship between the mandibular third molar and the mandibular canal by axial computed tomography with coronal and sagittal reconstruction.

OBJECTIVE: We sought to evaluate the relationship between the mandibular third molar and the mandibular canal by using axial computed tomography with coronal and sagittal reconstruction for third molar surgery. STUDY DESIGN: Forty-seven impacted third molars in 41 patients were found in close association with the mandibular canal during a panoramic radiographic assessment. The relationship between the mandibular third molar and the mandibular canal was evaluated by using computed tomography and compared in terms of operative exposure of the inferior alveolar nerve and postoperative labial dysesthesia. RESULTS: Twenty-four (51%) mandibular canals were buccal relative to the third molar, 12 were lingual, 9 were inferior, and 2 were between roots. At the time of the surgical procedure, the inferior alveolar nerve was visible in 7 patients. Postoperative lower lip dysesthesia occurred in 1 patient whose mandibular canal was in the lingual position. CONCLUSIONS: Axial computed tomography with coronal and sagittal reconstruction provides useful information to surgeons regarding the relationship between the mandibular third molar and the mandibular canal.

Use of third molar transplantation for closure of the oroantral communication after tooth extraction: a report of 2 cases.

OBJECTIVE: This clinical report introduces a promising and unique method for the immediate closure of the oroantral communication (OAC) after tooth extraction: the use of the transplanted third molar with closed apices. STUDY DESIGN: In 2 adult patients, OAC caused by the extraction of an upper molar was immediately closed by using a transplanted third molar with complete root formation. After tooth extraction at the recipient site, OAC with perforated mucosa of the sinus floor was confirmed and the donor third molar was transferred to the prepared recipient socket. Endodontic therapy of the transplanted third molar began at 3 weeks after surgery, and prosthetic treatment was completed at 5 months after the operation. These 2 patients were carefully observed both clinically and radiographically. RESULTS: Closure of the OAC was successfully performed, and the transplanted teeth became fixed with the passage of time in these 2 patients. Root resorption did not occur, and good functional results were obtained without any complications. CONCLUSIONS: Tooth transplantation of a mature third molar for closure of the OAC is a simple and excellent method because the transplanted tooth not only closes the communication to the maxillary sinus, but it also satisfactorily functions at the recipient site during mastication, even in adult patients.

Prospective comparison of 18F-FDG PET with conventional imaging modalities (MRI, CT, and 67Ga scintigraphy) in assessment of combined intraarterial chemotherapy and radiotherapy for head and neck carcinoma.

UNLABELLED: To preserve the oral organs and functions in patients with head and neck carcinoma, accurate determination of the appropriate treatment after neoadjuvant chemotherapy and radiotherapy is of critical importance. We evaluated the diagnostic accuracy of (18)F-FDG PET relative to that of other conventional imaging modalities in the assessment of therapeutic response after combined intraarterial chemotherapy and radiotherapy as an organ preservation protocol. METHODS: The study was prospectively performed on 23 consecutive patients with head and neck squamous cell carcinoma who completed the treatment regimen and underwent 2 (18)F-FDG PET studies before and after neoadjuvant chemoradiotherapy. (67)Ga scintigraphy (only before therapy) as well as MRI and CT (both before and after therapy) were also performed. All images were blindly and independently interpreted without knowledge of histologic findings. The level of confidence in image interpretation was graded by means of a 5-point rating system (0 = definitely no tumor to 4 = definite tumor). RESULTS: Before treatment, (18)F-FDG PET detected primary tumors in all 23 patients and was more sensitive (100%) than MRI (18/23; 78.3%), CT (15/22; 68.2%), and (67)Ga scintigraphy (8/20; 40%), with a confidence level of 3 or 4 as a positive tumor finding. After chemoradiotherapy, residual tumors were histologically confirmed in 4 patients (pathologic complete response rate, 19/23; 82.6%). Although posttreatment (18)F-FDG PET showed almost equal sensitivity (4/4; 100%) compared with MRI (3/3; 100%) or CT (3/4; 75%), its specificity (17/19; 89.5%) was superior to MRI (7/17, 41.2%) and to CT (10/17; 58.8%) for primary lesions. Regarding metastases to neck lymph nodes, only specificity for posttreatment images was calculated because no metastasis was confirmed in any patients after treatment. Six subjects had (18)F-FDG PET-positive lymph nodes, which had pathologically no tumor cells and suggested an inflammatory reactive change after therapy. Therefore, the specificity of posttreatment (18)F-FDG PET (17/23; 73.9%) was almost identical to that of MRI (17/20; 85%) and CT (16/21; 76.2%) for neck metastasis. With combined chemoradiotherapy monitored with (18)F-FDG PET, 8 patients avoided surgery and the remaining 15 patients underwent a reduced form of surgery. CONCLUSION: (18)F-FDG PET facilitates differentiation of residual tumors from treatment-related changes after chemoradiotherapy, which may be occasionally difficult to characterize by anatomic images. (18)F-FDG PET has a clinical impact for the management of patients with head and neck cancers after neoadjuvant chemoradiotherapy by optimizing surgical treatment for each patient and contributes to the improvement of the patient's quality of life.

FDG-PET for prediction of tumour aggressiveness and response to intra-arterial chemotherapy and radiotherapy in head and neck cancer.

The aim of this study was to evaluate the possible usefulness of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) for predicting tumour aggressiveness and response to intra-arterial chemotherapy (THP-ADM + 5-FU + carboplatin) and radiotherapy in head and neck carcinomas. Twenty patients with squamous cell carcinoma (SCC) of the head and neck were included in the study. All patients completed the treatment regimen, and each patient underwent two FDG-PET studies, one prior to and one at 4 weeks after the chemoradiotherapy. For the quantitative evaluation of regional FDG uptake in the tumour, standardised uptake values (SUVs) with an uptake period of 50 min were used. The pre-treatment SUV (pre-SUV) and post-treatment SUV (post-SUV) were compared with immunohistologically evaluated tumour proliferative potential (MIB-1 and PCNA), tumour cellularity and other parameters including histological grade, tumour size and stage, clinical response and histological evaluation after therapy. All neoplastic lesions showed high SUVs (mean, 9.75 mg/ml) prior to the treatment, which decreased significantly after the therapy (3.41 mg/ml, P<0.01). Pre-SUV did not show any correlation with MIB-1, PCNA, cellularity or other parameters. However, lower post-SUV was significantly correlated with good histological results after therapy (no viable tumour cells, n=16). In comparison with moderately differentiated SCCs, well-differentiated SCCs exhibited significantly lower post-SUV and a larger difference between pre- and post-SUVs. Lesions with a high pre-SUV (>7 mg/ml) showed residual tumour cells after treatment in 4 out of 15 patients, whereas patients whose lesions showed a low pre-SUV (<7 mg/ml, five patients) were successfully treated. Four out of six tumours with a post-SUV higher than 4 mg/ml had viable tumour cells, whereas all tumours (14/14) with a post-SUV lower than 4 mg/ml showed no viable tumour cells. Computational multivariate analysis using multiple regression revealed four factors (MIB-1 labelling index, cellularity, the number of MIB-1 labelled tumour cells and tumour size grade) contributing to pre-SUV and pre-post SUV (difference between pre-treatment SUV and post-treatment SUV in each patient) with statistical significance. FDG uptake in the tumour might reflect tumour aggressiveness, which is closely related to the proliferative activity and cellularity. Pre-treatment FDG-PET is useful in predicting the response to treatment, and post-treatment FDG-PET is of value in predicting residual viable tumours. FDG-PET has a profound impact on the treatment strategy for head and neck carcinomas.

Treatment of severe mandibular prognathism in combination with maxillary hypoplasia: case report.

We performed a Le Fort I osteotomy and sagittal split ramus osteotomy (Obwegeser-Dal Pont) combined with mandibular anterior segmental osteotomy without tooth extraction for a patient with severe mandibular prognathism accompanied by a hypoplastic maxilla, anterior open bite and normal anterior mandibular vertical dimension. The results of facial appearance and occlusion were excellent. This combined surgical method appears to be satisfactory for treating severe mandibular prognathism with hypoplastic maxilla.

Observation of molecular changes of a necrotic tissue from a murine carcinoma by Fourier-transform infrared microspectroscopy.

PURPOSE: Our purpose is to develop infrared (IR) microspectroscopy as a new optical diagnostic tool to support conventional lightscopic techniques in investigating the viability of carcinoma tissues and to develop its use in the evaluation of the early effects of anticancer therapy by monitoring the IR spectra in the necrotic area. EXPERIMENTAL DESIGN: We evaluated the tissue which amassed for 4 weeks after the isotransplantation of mouse squamous cell carcinoma into the thigh of mice. The borders of the necrotic area of frozen tissue specimens were investigated by Fourier-transform IR microspectroscopy and conventional histological staining. RESULTS: A significantly higher accumulation of cholesterol was observed in the necrotic tissue of a carcinoma. The mechanism of this phenomenon is hitherto unrecognized. We proposed that the accumulated cholesterol may lie extracellularly as a result of the ruptured plasma and internal membranes after the swelling of the necrotic cells brought on by hypoxia. The analysis of the secondary structure of protein revealed that the amounts of beta-sheet increased significantly in striking contrast to the decreasing amounts of alpha-helix in a necrotic area of a carcinoma. It is plausible that this structural conversion of protein was because of lipid-autooxidation products, such as cholesterol oxide but not cholesterol itself, which possesses cell toxicity and could be generated in a necrotic area. CONCLUSIONS: We conclude that it will be possible to evaluate the efficacy of the clinical treatment of carcinoma by monitoring subtle biological changes of cholesterol absorbance in the early stage of necrosis because of anticancer treatment.

Whole-body (18)F-fluorodeoxyglucose positron emission tomography in patients with head and neck cancer.

OBJECTIVE: Because of the high risk of secondary primary malignancies in addition to possible distant metastases, whole-body evaluation is critically important in patients with head and neck cancer. We evaluated the clinical usefulness of whole-body (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) before initial treatment. STUDY DESIGN: We performed whole-body FDG PET in 26 patients with head and neck cancer (squamous cell carcinoma, n = 20; salivary gland carcinoma, n = 6) before initial treatment. FDG images were prospectively evaluated, and further imaging studies were performed if required. Final diagnosis for the presence or absence of distant lesions was made by analysis of the pathologic findings of surgical specimens or by analysis of the clinical follow-up data for more than 1 year. RESULTS: PET images showed FDG avid lesions distant from the head and neck area in 3 of 26 patients (11.5%). Two patients were confirmed to have secondary primary cancer (one with colon cancer in the early stage and another with small lung metastasis from postoperative colon cancer). They were diagnosed and treated properly both for the head and neck cancer and the secondary primary cancer. One patient was confirmed to have large lung metastasis from head and neck cancer, and appropriate treatment was selected. CONCLUSIONS: Whole-body FDG PET has a clinical impact on the management of patients with head and neck cancer by detecting secondary primary malignancies as well as distant metastases.