Analysis of carotid artery deformation in different head and neck positions for maxillofacial catheter navigation in advanced oral cancer treatment

ABSTRACT: BACKGROUND: To improve the accuracy of catheter navigation, it is important to develop a method to predict shifts of carotid artery (CA) bifurcations caused by intraoperative deformation. An important factor affecting the accuracy of electromagnetic maxillofacial catheter navigation systems is CA deformations. We aimed to assess CA deformation in different head and neck positions. METHODS: Using two sets of computed tomography angiography (CTA) images of six patients, displacements of the skull (maxillofacial segments), C1--C4 cervical vertebrae, mandible (mandibular segment), and CA along with its branches were analyzed. Segmented rigid bones around CA were considered the main causes of CA deformation. After superimposition of maxillofacial segments, C1--C4 and mandible segments were superimposed separately for displacement measurements. Five bifurcation points (vA--vE) were assessed after extracting the CA centerline. A new standardized coordinate system, regardless of patient-specific scanning positions, was employed. It was created using the principal axes of inertia of the maxillofacial bone segments of patients. Position and orientation parameters were transferred to this coordinate system. CA deformation in different head and neck positions was assessed. RESULTS: Absolute shifts in the center of gravity in the bone models for different segments were C1, 1.02 +/- 0.9; C2, 2.18 +/- 1.81; C3, 4.25 +/- 3.85; C4, 5.90 +/- 5.14; and mandible, 1.75 +/- 2.76 mm. Shifts of CA bifurcations were vA, 5.52 +/- 4.12; vB, 4.02 +/- 3.27; vC, 4.39 +/- 2.42; vD, 4.48 +/- 1.88; and vE, 2.47 +/- 1.32. Displacements, position changes, and orientation changes of C1--C4 segments as well as the displacements of all CA bifurcation points were similar in individual patients. CONCLUSIONS: CA deformation was objectively proven as an important factor contributing to errors in maxillofacial navigation. Our study results suggest that small movements of the bones around CA can result in small CA deformations. Although patients' faces were not fixed properly during CT scanning, C1--C4 and vA--vE displacements were similar in individual patients. We proposed a novel method for accumulation of the displacement data, and this study indicated the importance of surrounding bone displacements in predicting CA bifurcation.     

Profiling of a microbial community under confined conditions in a fed-batch garbage decomposer by denaturing gradient gel electrophoresis

In order to determine the conditions for the maximum performance of a fed-batch composting (FBC) reactor, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was used to analyze the microbial communities established under the confined conditions of moisture content and environmental temperature. To evaluate the effects of microbial community structures on the performance of FBC reactors, degradation experiments using small-scale reactors and model waste were conducted under confined environmental conditions. A high degradation rate was observed under a wide range of MC conditions (30-60%) and at higher than usual temperatures (30-50 degrees C). The microbial communities that formed in the experimental FBC reactors were analyzed by DGGE of PCR-amplified 16S rRNA genes. The DGGE banding patterns at the same level as the degradation rates were similar even if the environmental conditions were different. Sequence analysis of the DGGE bands revealed the primary microbes which act in the reactor.     

Phospholipid composition and pheromonal activity of nuptial secretion of the male German cockroach, Blattella germanica

As a part of the sequential courtship behavior of the German cockroach, Blattella germanica, females feed on the nuptial secretion from the male tergal glands. The pheromonal secretion, consisting mainly of oligosaccharides and phospholipids, strongly elicits a feeding response in virgin females. The phospholipids were composed of phosphatidylethanolamine and phosphatidylcholine. Their fatty acid compositions were determined by chromatographic and enzymatic methods. Although an authentic blend of phospholipids (1,2-dioleoylphosphatidylethanolamine and 1,2-dioleoylphosphatidylcholine) showed a marginal phagostimulant activity, addition of the blend to an authentic blend of oligosaccharides (maltose and maltotriose) strongly enhanced the activity to nearly the level of the crude extract. These results indicate that the nuptial feeding behavior is elicited by a synergistic action between phospholipids and oligosaccharides.     

Bcl‐2 rescues motoneurons from early cell death in the cervical spinal cord of the chicken embryo

Motoneurons (MNs) in the cervical spinal cord of the chicken embryo undergo programmed cell death (PCD) between embryonic day (E) 4 and E5. The intracellular molecules regulating this early phase of PCD remain unknown. Here we show that introduction of Bcl‐2 by a replication‐competent avian retroviral vector prevented MN degeneration at E4.5, whereas the expression of the green fluorescent protein (GFP) was ineffective. Bcl‐2 expression did not affect the number of Islet‐1/2‐positive MNs at the onset of cell death (E4). However, when examined at the end of the cell death period (E5.5), the number of Islet‐1/2‐positive MNs was clearly increased in Bcl‐2‐transfected embryos compared with control and GFP‐transfected embryos. Activation of caspase‐3, which is normally observed in this early MN death, was also prevented by Bcl‐2. Thus, MNs in the cervical spinal cord appear to use intracellular pathway(s) for early PCD that is responsive to Bcl‐2. © 2002 Wiley Periodicals, Inc. J Neurobiol 53: 381–390, 2002     

Ultrastructure of pleural mesothelioma and pulmonary adenocarcinoma in malignant effusions as compared with reactive mesothelial cells.

OBJECTIVE: To determine the ultrastructural features of diffuse malignant pleural mesothelioma cells in cytologic specimens from pleural effusions. STUDY DESIGN: We retrospectively studied 35 pleural effusions: 12 diffuse malignant pleural mesotheliomas (8 epithelial type, 4 biphasic type), 12 pulmonary adenocarcinomas and 11 cases of reactive mesothelial cells. RESULTS: In the cytoplasm, reactive and malignant mesothelial cells had more-abundant intermediate filaments (P < .05, P < .01) and fewer free ribosomes (P < .001, P < .001) than adenocarcinoma cells. Reactive mesothelial cells had fewer mitochondria than mesothelioma cells (P < .05). Mesothelioma cells had longer, thinner microvilli on the cell surfaces (P < .001); length/diameter ratios of microvilli were 19.1 +/- 7.0 (mesothelioma) vs. 9.1 +/- 2.2 (adenocarcinoma) and 9.2 +/- 2.4 (mesothelial cells). Giant intercellular junctions (desmosomes or desmosomelike structures > 1 micron in length) were found in eight cases of mesothelioma. Core filaments or rootlets in microvilli were present in two cases of adenocarcinoma. CONCLUSION: Because cytologic specimens from pleural effusions were easy to obtain, we think ultrastructural cytology is useful in distinguishing mesothelioma from adenocarcinoma and benign effusions.     

CIZ/NMP4 is expressed in B16 melanoma and forms a positive feedback loop with RANKL to promote migration of the melanoma cells

Tumor metastasis to bone is a serious pathological situation that causes severe pain, and deterioration in locomoter function. However, the mechanisms underlying tumor metastasis is still incompletely understood. CIZ/NMP4 is a nucleocytoplasmic shuttling protein and its roles in tumor cells have not been known. We, therefore, hypothesized the role of CIZ/NMP4 in B16 melanoma cells that metastasize to bone. CIZ/NMP4 is expressed in B16 cells. The CIZ/NMP4 expression levels are correlated to the metastatic activity in divergent types of melanoma cells. Overexpression of CIZ/NMP4 increased B16 cell migration in Trans-well assay. Conversely, siRNA-based knockdown of CIZ/NMP4 suppressed migratory activity of these cells. As RANKL promotes metastasis of tumor cells in bone, we tested its effect on CIZ in melanoma cells. RANKL treatment enhanced CIZ/NMP4 expression. This increase of CIZ by RANKL promoted migration. Conversely, we identified CIZ/NMP4 binding site in the promoter of RANKL. Furthermore, luciferase assay indicated that CIZ/NMP4 overexpression enhanced RANKL promoter activities, revealing a positive feedback loop of CIZ/NMP4 and RANKL in melanoma. These observations indicate that CIZ/NMP4 is critical regulator of metastasis of melanoma cells.     

Changes in the Composition of Headspace Volatiles of Flue-cured Tobacco by Aging

In order to investigate the headspace volatiles which indicate the againg effect on tobacco, the headspace volatiles of Japanese flue-cured tobacco were collected by active carbon and analyzed by gas chromatography. The data obtained were subjected to principal component analysis (PCA) and stepwise discriminant analysis (SDA). The results of PCA showed that the volatiles indicated the effect of aging on smoking quality. The SDA selected six peaks of the volatiles which classified the samples into four groups according to the aging period. The results described above can show that the relative proportions of the volatiles, such as furfuryl alcohol, benzyl alcohol and solanone, may be used to judge approximately the agint effects on tobacco.