Influence of pharyngeal airway respiration pressure on Class II mandibular retrusion in children: A computational fluid dynamics study of inspiration and expiration.

OBJECTIVES: To examine the influence of negative pressure of the pharyngeal airway on mandibular retraction during inspiration in children with nasal obstruction using the computational fluid dynamics (CFD) method. SETTING AND SAMPLE POPULATION: Sixty-two children were divided into Classes I, II (mandibular retrusion) and III (mandibular protrusion) malocclusion groups. MATERIAL AND METHODS: Cone-beam computed tomography data were used to reconstruct three-dimensional shapes of the nasal and pharyngeal airways. Airflow pressure was simulated using CFD to calculate nasal resistance and pharyngeal airway pressure during inspiration and expiration. RESULTS: Nasal resistance of the Class II group was significantly higher than that of the other two groups, and oropharyngeal airway inspiration pressure in the Class II (-247.64 Pa) group was larger than that in the Class I (-43.51 Pa) and Class III (-31.81 Pa) groups (P<.001). The oropharyngeal airway inspiration-expiration pressure difference in the Class II (-27.38 Pa) group was larger than that in the Class I (-5.17 Pa) and Class III (0.68 Pa) groups (P=.006). CONCLUSION: Large negative inspiratory pharyngeal airway pressure due to nasal obstruction in children with Class II malocclusion may be related to their retrognathia.

Generation of α-1,3-Galactosyltransferase-Deficient Porcine Embryonic Fibroblasts by CRISPR/Cas9-Mediated Knock-in of a Small Mutated Sequence and a Targeted Toxin-Based Selection System.

The CRISPR/Cas9 system has enabled the editing of mammalian genomes; however, its applicability and efficiency in the pig genome has not been studied in depth. The α-gal epitope synthesized by α-1,3-galactosyltransferase gene (GGTA1) is known as a xenoantigen obtained upon pig-to-human xenotransplantation. We here employed the CRISPR/Cas9 system-mediated knock-in of endogenous GGTA1 via targeted homologous recombination (HR). Linearized donors with ~800-bp homology flanking the CRISPR/Cas9 target site [exon 4 (containing ATG) of GGTA1] served as a template for gene targeting by HR. Using a targeted toxin strategy to select clones lacking α-gal epitope expression, we successfully obtained several knock-in clones within 3 weeks of initial transfection. These results suggest that the use of CRISPR/Cas9-mediated HR to knock-in a mutated fragment at defined loci represents an efficient strategy to achieve the rapid modulation of genes of interest in swine cells and is a promising tool for the creation of KO piglets.

Induction of tissue-specific stem cells by reprogramming factors, and tissue-specific selection.

Although induced pluripotent stem (iPS) cells have significant implications for overcoming most of the ethical issues associated with embryonic stem (ES) cells, there are still several unresolved issues related to the use of iPS cells for clinical applications, such as teratoma formation. In this study, we were able to generate tissue-specific stem (induced tissue-specific stem; iTS) cells from the pancreas (iTS-P) or liver (iTS-L) by transient overexpression of reprogramming factors, combined with tissue-specific selection. The generation of iTS cells was easier than that of iPS cells. The iTS-P/iTS-L cells express genetic markers of endoderm and pancreatic/hepatic progenitors and were able to differentiate into insulin-producing cells/hepatocytes more efficiently than ES cells. Subcutaneous transplantation of both types of iTS cells into immunodeficient mice resulted in no teratoma formation. The technology used for the transient overexpression of reprogramming factors and tissue-specific selection may be useful for the generation of other tissue-specific stem cells, and the generation of iTS cells could have important implications for the clinical application of stem cells.

Association between mouth opening and upper body movement with intake of different-size food pieces during eating.

Head rotation is coordinated with mandibular movement during mouth opening, and the range of head rotation and mouth opening change with food size. However, past research did not include upper body movement, and no reports have related head and mandibular movement during realistic eating. The purpose of this study was to analyse head and mandibular movements with intake of different-sized food pieces during realistic eating. The test food consisted of apple cut into two different cube sizes (10mm and 20mm). Head and mandibular movements of 20 healthy young adults eating the apple pieces were simultaneously recorded in three dimensions by a wireless opto-electronic system. Reflective markers were attached to the upper lip and chin to measure the mouth opening range. Five markers were attached to eyeglasses frames to measure linear motion and rotation of the head. One marker was attached to the jugular notch of the sternum to measure linear motion of the upper body. Linear motion, and the inclination angle of the head and upper body, and mouth opening range were compared during intake of different-sized apple pieces. Mouth opening, head-neck rotation angle and the amount of upper body forward translation and inclination increased with larger apple pieces. However, isolated relative head motion was stabilized. We conclude that upper body forward motion and head-neck rotation assist mouth opening whilst stabilizing head orientation, and that the range of head-neck rotation angle, upper body translation and range of mouth opening change with food size during realistic eating.

Head motion may help mouth opening in children.

Concomitant head and mandibular movement during jaw function is well known in adults; however, its importance in children has not been studied. The brain attains 85-90% of its adult weight at 5 years of age, though the maximum rate of condylar growth is attained at approximately 14 years of age. These findings suggest that the coordination of the head and mandible may differ between children and adults. This study investigated head and mandibular movements of 19 children with complete primary dentition (average age: 5 years 5 months) and compared their functional integration of jaw and head movements to those of 16 female adults (average age: 20 years 3 months) with permanent dentition. Although the mandibular opening distance was significantly greater in the adults, the magnitude of concomitant head motion was greater in children. The results suggest that head extension in children helps increase the magnitude of mouth opening more than in adult women.

Is the reverse cycle during chewing abnormal in children with primary dentition?

The purpose of this study was to clarify whether the reverse cycle during chewing is abnormal in children with primary dentition. Children with normal primary dentition (N = 23; 5.5 +/- 0.8 years) and female adults (N = 25; 20.7 +/- 1.9 years) participated in this study. Chewing movement was recorded using an opto-electronic analysis system with six degrees-of-freedom (TRI-MET, Tokyo-shizaisha; Tokyo, Japan). Each subject was given a stick of chewing gum (new TRIDENT, WARNER-LAMBERT CO., Morris Plains, NJ, USA) and instructed to chew it normally. Starting from the maximum intercuspal position, each chewing sequence was recorded over a period of 20 s. A custom computer program identified individual chewing cycles. Frontal views were used to distinguish seven types of cycle shapes according to Ahlgren (Acta Odontol Scand, 24, 1966, 1-109; Acta Odontol Scand, 25, 1967, 3-13). Multilevel statistical models evaluated differences between children and adults. In the adults, type II cycles that initially opened towards the balancing side and then moved towards the working side were the most common, and the closing pathway was lateral to the opening pathway. In the children, type V (reverse) cycles that opened towards the working side were most common, the closing pathway was medial to the opening pathway, and there was a smaller lateral component during opening and closing than in adults (P < 0.05). We conclude that the reverse cycle is not abnormal because normal children with primary dentition have a smaller lateral component and difficulty in controlling asymmetric muscle activity.

Correlations between incisor and condylar movements during lateral excursion in children with primary dentition.

The purpose of this study was to look for associations between lower incisor movement and working and balancing condylar movement during lateral excursion in children with primary dentition and adults with permanent dentition. Mandibular movement was recorded using a TRI-MET (an optoelectronic analysis system with six degrees-of-freedom) at a sampling frequency of 100 Hz. The movement data was transferred to a graphics workstation for analysis. Subjects were categorized by age into two groups. The primary dentition group consisted of 19 children (mean age: 5 years and 5 months, s.d.: 8.7 months), and the permanent dentition group consisted of 22 women (mean age: 20 years and 5 months, s.d.: 26.3 months). The occlusion and TMJ in both groups were normal, with no history of orthodontic treatment. Three orthogonal excursive ranges and the 3D linear distance of the incisal and balancing and working condylar points, along with inter- and intra-individual correlations between the incisor and the balancing and working condyles during lateral excursion, were estimated by using multilevel statistical models. Lateral excursion in children with primary dentition was characterized by smaller incisor excursive ranges and 3D linear distance than in adults, and stronger inter- and intra-individual correlations between incisor and balancing condylar movements than in adults. In both children and adults the lateral excursion of the incisor was a good indicator of the extent of balancing condylar movement, but not working condylar movement.

Craniofacial growth and functional change in oligodontia with ectodermal dysplasia: a case report.

A case of ectodermal dysplasia in a Japanese boy is presented in this report. After prosthetic treatment was performed with partial dentures in both jaws, mandibular movement, dental casts, and lateral and frontal cephalograms were taken at an initial visit (age 7 years 8 months), and at follow-up 1 year and 8 months later (age 9 years 3 months) to evaluate the developmental changes in masticatory movement, dental arch width, and craniofacial morphology. Stability of the jaw movements improved during the follow-up period both with and without dentures. The facial skeleton grew between the initial visit and follow-up. Mandibular length remained long compared with the average value for Japanese children. A possible genetic marker for mandibular growth (growth hormone receptor), which is considered to be an important factor in mandibular growth and development, was analysed for the gene variant and the result supported the characteristic mandibular growth in the reported case. These results indicate the characteristic craniofacial growth in this disease and emphasize the potential ability of functional development of jaw movements with oligodontia.

Antiangiogenic activity of BAI1 in vivo: implications for gene therapy of human glioblastomas.

Glioblastomas are the most common primary brain tumors in adults. These tumors exhibit a high degree of vascularization, and malignant progression from astrocytoma to glioblastoma is often accompanied by increased angiogenesis and the upregulation of vascular endothelial growth factor and its receptors. In this study, we investigated the in vivo antiangiogenic and antitumor effects of brain-specific angiogenesis inhibitor 1 (BAI1) using human glioblastoma cell lines. Glioblastoma cells were transduced with an adenoviral vector encoding BAI1 (AdBAI1), and Northern and Western blot analyses, respectively, demonstrated BAI1 mRNA and protein expression in the transduced tumor cells. Using an in vivo neovascularization assay, we found that angiogenesis surrounding AdBAI1-transduced glioblastoma cells transplanted into transparent skinfold chambers of SCID mice was significantly impaired compared to control treated cells. Additionally, in vivo inoculation with AdBAI1 of established subcutaneous or intracerebral transplanted tumors significantly impaired tumor growth and promoted increased mouse survival. Morphologically, the tumors exhibited signs of impaired angiogenesis, such as extensive necrosis and reduced intratumoral vascular density. Taken together, these data strongly indicate that BAI1 may be an excellent gene therapy candidate for the treatment of brain tumors, especially human glioblastomas.

Characteristics of the gum chewing occlusal phase in children with primary dentition.

Understanding of the growth and development of mandibular function is indispensable to the diagnosis of functional disturbances during childhood. The purpose of this study was to clarify the characteristics of the occlusal phase during gum chewing in children with primary dentition. Chewing motion at the working molar of 14 children with primary dentition and 28 female adults was recorded optoelectrically, and the frontal and sagittal angles of their closing and following opening strokes were measured and compared. In children the closing strokes were entered more vertically and anteriorly than in adults, and the opening strokes shifted to the non-working side in adults but moved to the working side in children. The degree of variance also differed between the two groups; the variance of the frontal angle was larger than that of sagittal angle in adults, but the opposite was true in children. These results suggested that the chewing pattern in children during the occlusal phase is distinctly different from adults and the chewing movement in children is not always less stable than in adults.

Length of the occlusal glide during chewing in children with primary dentition.

Chewing is one of the most important functions of the mandible, but, to date, there are very few studies of this function in children. The purpose of this study was to quantify the length of the occlusal glide at the lower incisal point during gum chewing in children with primary dentition. Eleven girls with primary dentition were selected for this study. Mandibular excursions with occlusal contacts and gum chewing movement were measured using an optoelectronic system that can measure mandibular movement with six degrees-of-freedom at a sampling frequency of 100 Hz. A curved mesh diagram of incisor coordinates during mandibular excursions was established to calculate the length of the occlusal glide for each subject. The occlusal glide lengths of children were compared with previously reported results for adults. The estimated length of the occlusal glide during closing was significantly shorter in children than in adults, contrary to that during opening. This result suggests that children have a characteristic chewing pattern that differs from adults.

Occlusal phase of gum-chewing strokes.

The occlusal phase of chewing is especially interesting because food particles are being pulverized in this phase. For efficient chewing the upper and lower teeth must come together in a congruent fashion with less variation than in other phases. To examine this expectation the chewing motions of 28 women were recorded optoelectrically, and their frontal and sagittal angles of the closing and following opening strokes were measured at 3.0 mm (3-D linear distance) of opening. Closing strokes were more stable than opening strokes. The frontal angle was correlated with the sagittal angle during closing. The opening and closing sagittal angles were moderately correlated, and the opening and closing frontal angles were negatively correlated at the intersubject level. No direct association was found between the closing strokes and following opening strokes at the intra-subject level. These results suggest that closing strokes are more stable than opening strokes, resulting in efficient mastication.

Length of the occlusal glide at the lower incisal point during chewing.

The purpose of this study was to estimate the length of the occlusal glide during gum chewing at the lower incisal point. Mandibular excursions with occlusal contacts in 25 females with permanent dentition were recorded using an optoelectronic system that can measure mandibular movement with 6 d.f. at a sampling frequency of 100 Hz. A curved mesh diagram of incisor coordinates during maximum mandibular excursions (CMDME) was plotted. Gum chewing movement was also measured using the same system and computer software which divided the chewing movement into cycles at each maximum opening position. Each cycle was standardized at 0.1 mm intervals from the most closed position. Finally, the distance between the CMDME and each position of the incisor during a chewing cycle was calculated. Whenever, this distance was less than 0.2 mm opposing teeth were considered to be in contact. The occlusal glide was defined as the distance travelled by the lower incisal point as the mandible moved along occlusal contacts of the CMDME. The vertical coordinates at the beginning of the occlusal glide (during closing) and at the end of occlusal glide (during opening) were also calculated. The lengths of the occlusal glide pathway averaged 1.29 mm during closing and 1.55 mm during opening, a total length of 2.84 mm. Mean vertical coordinates at the beginning and end of the glide were -0.95 and -1.12 mm from intercuspal position, respectively.

Haematopoietic progenitor cells from the common marmoset as targets of gene transduction by retroviral and adenoviral vectors.

To establish a new non-human primate model for human cytokine and gene therapy, we characterized lymphocytes and haematopoietic progenitor cells of the small New World monkey, the common marmoset. We first assessed the reactions of marmoset bone marrow (BM) and peripheral blood (PB) cells to mouse anti-human monoclonal antibodies (mAbs) for the purpose of isolating marmoset lymphocytes and haematopoietic progenitor cells. Both cell fractions stained with CD4 and CD8 mAbs were identified as lymphocytes by cell proliferation assay and morphological examination. Myeloid-specific mAbs such as CD14 and CD33 did not react with marmoset BM and PB cells. No available CD34 and c-kit mAbs could be used to purify the marmoset haematopoietic progenitor cells. Furthermore, we studied the in vitro transduction of the bacterial beta-galactosidase (LacZ) gene into CFU-GM derived from marmoset BM using retroviral and adenoviral vectors. The transduction efficiency was increased by using a mixed culture system consisting of marmoset BM stromal cells and retroviral producer cells. It was also possible to transduce LacZ gene into marmoset haematopoietic progenitor cells with adenoviral vectors as well as retroviral vectors. The percentage of adenovirally transduced LacZ-positive clusters was 15% at day 4 (multiplicity of infection=200), but only 1-2% at day 14. The differential use of viral vector systems is to be recommended in targeting different diseases. Our results suggested that marmoset BM progenitor cells were available to examine the transduction efficiency of various viral vectors in vitro.

[A case of successful palliative operation of asplenia syndrome with total anomalous pulmonary venous return in young infant].

We reported a successful palliative operation for asplenia syndrome with total anomalous pulmonary venous return (TAPVR Ia) in an infant. The boy was suffering from cyanosis and tachypnea. He was diagnosed as asplenia syndrome with TAPVR and hiatus hernia. After he was admitted to our hospital, pulmonary congestion gradually progressed in a month. At 58 days of age, a palliative operation (repair of TAPVR and pulmonary artery banding with band of 20 mm in length) was performed. The postoperative course was uneventful. At 114 days of age, he underwent curative operation for hiatus hernia without cardiac failure. Postoperative cardiac catheterization at 179 days of age showed appropriate pulmonary artery pressure. We emphasize that pulmonary artery banding which is tighter than usual well controls pulmonary blood flow, although the length of the band in each case should be considered individually.

Dedifferentiation of adenocarcinomas by activation of phosphatidylinositol 3-kinase.

Signet ring cell carcinoma is a malignant type of poorly differentiated adenocarcinomas in stomach, which is characterized by the occasional presence of signet ring-like cancer cells. We found that expression of constitutively active phosphatidylinositol 3-kinase (PI 3-kinase) in well differentiated adenocarcinoma cell lines induced the loss of cell-cell contact and some of the cells changed their shapes to signet ring cell-like, characterized by appearance of mucus droplets in the cytoplasm with well developed endplasmic reticulum and Golgi complexes. The active PI 3-kinase-expressing cells formed poorly differentiated tumors in nude mice, which were clearly different from those of the original cell lines. The PI 3-kinase activities detected in anti-phosphotyrosine immunoprecipitates were higher in several signet ring cell carcinoma-derived cell lines than in other adenocarcinoma cell lines. In addition, PI 3-kinase was found to be associated with a 200-kDa protein phosphorylated in tyrosine in 4 of 6 signet ring cells but not in other cell lines, suggesting that PI 3-kinase is possibly activated in these cells by binding to the 200-kDa protein. The 200-kDa protein-PI 3-kinase complex was exclusively fractionated in the membrane fractions. The specific activity of the PI 3-kinase immunoprecipitated with anti-phosphotyrosine antibody was approximately 3-fold higher than that with anti-PI 3-kinase antibody. These results suggest that PI 3-kinase in signet ring cell carcinoma is recruited to the membrane and activated by the binding to the 200-kDa protein.

A method to measure the solubility of drugs in ointment bases.

The solubility of a drug in an ointment base is an important factor determining the efficacy of the formulation. However, it is difficult to measure the solubility of drugs in ointment bases. Thus, a rapid and simple method to determine the solubility of drugs in ointment bases was investigated. Using oxybenzone as a model drug, the bleeding liquid which leaked out from various ointments was collected, and the drug concentration in the bleeding liquid was measured. The drug concentrations in the bleeding liquid collected from soluble type ointments in which the drug is dissolved in bases were in accord with that in the ointments. On the other hand, the drug concentrations in the bleeding liquid collected from crystal dispersion type ointments in which drug crystal are dispersed in bases were the same in spite of the variance in total drug concentrations in the ointments. It was confirmed by microscopic examination that crystals do not flow out into bleeding liquid in the crystal dispersion type ointment. It was also confirmed that the solubility of the drug obtained in the present study was in a solubility range consistent with microscopic examination. Furthermore, an increase in the drug solubility was detected by this method when the drug solubility in the base was raised by adding a detergent into the base. And the results from this method were in accord with the results from microscopic examination. These results suggest that the drug concentration in bleeding liquid represents the solubility of the drug in an ointment.

Debridement arthroplasty for osteoarthritis of the elbow.

For treatment of osteoarthritis of the elbow, the authors use debridement arthroplasty with a medial or lateral approach. Thirty-eight elbows in 36 patients treated with this procedure were examined. The age of the patients ranged from 20 to 71 years, with a mean age of 41.7 years. Cubital tunnel syndrome was present in 16 of the 38 (42%) elbows. The operations were performed through a lateral approach in four elbows, a lateral approach with medial skin incision for ulnar nerve neurolysis in 16 elbows, a medial approach in 10 elbows, and a medial plus a lateral approach in eight elbows. The followup ranged from 2 years to 12.1 years, with an average of 5.9 years. Complete pain relief or minimal elbow pain was reported in 95% of patients who had surgical treatment. The average gain in motion was 6 degrees extension and 18 degrees flexion. Results for the various surgical approaches did not show a statistically significant difference. Recurrence of bony spurs and ridges was analyzed additionally in 18 selected patients who could be observed more than 5 years after surgery (range, 5-12 years). Redevelopment of bony spurs on the coronoid process and olecranon tip occurred in all 18 patients, but those changes were graded as mild in 13 (74%) patients and moderate in five (16%) patients and were accompanied by no pain or slight pain. Elbow arthroplasty as used by the authors produces stable and reliable results for relief of pain, gains in range of motion, and the absence of recurrence of significant osteoarthritis.

Inhibition of migrating lens epithelial cells by blocking the adhesion molecule integrin: a preliminary report.

PURPOSE: To evaluate the preventive effect of blocking integrins by sustained release of RGD peptide (arginine-glycin-aspartic acid sequence) or a combination of RGD peptide and ethylenediaminotetraacetic acid (EDTA) on lens epithelial cell (LEC) migration. SETTING: Nishi Eye Hospital, Jinshikai Medical Foundation, Osaka, Japan. METHOD: A polylactic-glycolic acid disk containing 4% RGD or a combination of 23% EDTA and 10% RGD was implanted in the capsular bag in five rabbit eyes following standard cataract surgery. The release rate in vitro was 4.4 microg/h for RGD peptide alone and 7.8 and 7.6 microg/h for combined EDTA and RGD peptide, respectively. The contralateral eye received a disk without agents as a control. RESULTS: After 1 month, a slight inhibition of LEC migration onto the posterior capsule was observed histopathologically in eyes receiving RGD peptide. A significant inhibition was observed in eyes with combined EDTA and RGD. CONCLUSIONS: Application of RGD peptide and EDTA and RGD peptide may inhibit LEC migration by inhibiting the integrins expressed on the LECs. Blocking adhesion molecules expressed on LECs may reduce posterior capsule opacification.

Expression of a constitutively active phosphatidylinositol 3-kinase induces process formation in rat PC12 cells. Use of Cre/loxP recombination system.

It has been shown that inhibition of phosphatidylinositol (PI) 3-kinase blocks neurite outgrowth of PC12 cells stimulated with nerve growth factor. To further assess the role of PI 3-kinase, the active form of PI 3-kinase was expressed in PC12 cells by the adenovirus mediated introduction of a site-specific recombinase, Cre. After expression of the active PI 3-kinase, elevation of the levels of PI 3,4-diphosphate and PI 3,4,5-trisphosphate as well as formation of neurite-like processes was observed. The process formation was inhibited by wortmannin, a selective inhibitor of PI 3-kinase, which suggests that a high activity of PI 3-kinase was responsible for the formation of these processes. The processes lacked accumulation of F-actin and GAP43 at the growth cone, which suggests that the processes were incomplete compared with neurites. Instead, the bundling of microtubules was enhanced, which suggests that organization of the microtubules might be driving the process of elongation in the cells expressing the active PI 3-kinase. Induction of active PI 3-kinase resulted in activation of Jun N-terminal kinase but not of mitogen-activated protein kinase or protein kinase B/Rac protein kinase/Akt. These results suggest that PI 3-kinase is involved in neurite outgrowth in PC12 cells and that activation of Jun N-terminal kinase cascade may be involved in the cell response.