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1.
J R Soc Interface ; 21(214): 20230439, 2024 May.
Article in English | MEDLINE | ID: mdl-38807527

ABSTRACT

We present a novel approach to traction force microscopy (TFM) for studying the locomotion of 10 cm long walking centipedes on soft substrates. Leveraging the remarkable elasticity and ductility of kudzu starch gels, we use them as a deformable gel substrate, providing resilience against the centipedes' sharp leg tips. By optimizing fiducial marker size and density and fine-tuning imaging conditions, we enhance measurement accuracy. Our TFM investigation reveals traction forces along the centipede's longitudinal axis that effectively counterbalance inertial forces within the 0-10 mN range, providing the first report of non-vanishing inertia forces in TFM studies. Interestingly, we observe waves of forces propagating from the head to the tail of the centipede, corresponding to its locomotion speed. Furthermore, we discover a characteristic cycle of leg clusters engaging with the substrate: forward force (friction) upon leg tip contact, backward force (traction) as the leg pulls the substrate while stationary, and subsequent forward force as the leg tip detaches to reposition itself in the anterior direction. This work opens perspectives for TFM applications in ethology, tribology and robotics.


Subject(s)
Arthropods , Locomotion , Locomotion/physiology , Animals , Arthropods/physiology , Microscopy/methods
2.
Nat Commun ; 11(1): 4821, 2020 Sep 24.
Article in English | MEDLINE | ID: mdl-32973165

ABSTRACT

Materials that possess nontrivial topology and magnetism is known to exhibit exotic quantum phenomena such as the quantum anomalous Hall effect. Here, we fabricate a novel magnetic topological heterostructure Mn4Bi2Te7/Bi2Te3 where multiple magnetic layers are inserted into the topmost quintuple layer of the original topological insulator Bi2Te3. A massive Dirac cone (DC) with a gap of 40-75 meV at 16 K is observed. By tracing the temperature evolution, this gap is shown to gradually decrease with increasing temperature and a blunt transition from a massive to a massless DC occurs around 200-250 K. Structural analysis shows that the samples also contain MnBi2Te4/Bi2Te3. Magnetic measurements show that there are two distinct Mn components in the system that corresponds to the two heterostructures; MnBi2Te4/Bi2Te3 is paramagnetic at 6 K while Mn4Bi2Te7/Bi2Te3 is ferromagnetic with a negative hysteresis (critical temperature  ~20 K). This novel heterostructure is potentially important for future device applications.

3.
Neuropathol Appl Neurobiol ; 46(4): 344-358, 2020 06.
Article in English | MEDLINE | ID: mdl-31600825

ABSTRACT

AIMS: Globular glial tauopathy (GGT) is a new category within the 4-repeat tauopathies that is characterised neuropathologically by tau-positive globular glial inclusions (GGIs), namely, globular oligodendrocytic and astrocytic inclusions (GOIs and GAIs). Occurrence of tau-positive neuronal cytoplasmic inclusions (NCIs) is also a feature. GGT is classified into three pathological subtypes (Types I, II and III). We studied the tau pathology in 6 cases of GGT (Type II, n = 3; Type III, n = 3), with special reference to GAIs and NCIs. METHODS: Neuropathological examinations were conducted, along with immunohistochemistry, morphometry and three-dimensional imaging, and biochemical and genetic analysis of tau. RESULTS: The cortical GAIs in Type II and those in Type III were distinguishable from each other. In the motor cortex, GAIs were much more numerous in Type III than in Type II. Prominent occurrence of perikaryal globular structures was a feature of GAIs in Type III. By contrast, prominent occurrence of radiating process-like structures was a feature of GAIs in Type II. Overall, the GAIs were significantly smaller in Type III than in Type II. NCIs were divisible into three subgroups in terms of shape: diffuse granular, thick cord-like, and round/horseshoe-shaped structures. In all cases, NCIs were a feature of the upper and lower motor neurons. Interestingly, the round/horseshoe-shaped NCIs were observed only in Type III cases. CONCLUSIONS: These findings, which characterised GAIs and NCIs, indicated that Type II and Type III constitute two distinct pathological subtypes, and also further strengthen the concept of GGT as a distinct entity.


Subject(s)
Brain/pathology , Neuroglia/pathology , Neurons/pathology , Tauopathies/pathology , Aged , Aged, 80 and over , Female , Humans , Inclusion Bodies/pathology , Male
5.
Pharmazie ; 74(1): 62-63, 2019 01 01.
Article in English | MEDLINE | ID: mdl-30782252

ABSTRACT

Our case was a 70-year-old male (height: 168 cm, weight: 74.3 kg) with polypharmacy (total 15 drugs including 10 tablets) who was treated for HIV infection. His dosing schedule of raltegravir was changed from BID (a 400 mg tablet, twice) to QD (2x600 mg tablet, once). After a month, we found that he miss-took raltegravir for 1x600 mg tablet at once. His HIV-1 RNA increased from undetectable levels to < 20 copies per mL. Pharmaceutical companies should therefore carefully consider swallowing difficulties in old patients, such as by reformulating medications so that only one dosing is required per day and decreasing the size of tablets to 7-8 mm in diameter or orally distinguish tablet.


Subject(s)
Anti-HIV Agents/administration & dosage , HIV Infections/drug therapy , RNA, Viral/blood , Raltegravir Potassium/administration & dosage , Aged , Deglutition Disorders/physiopathology , Dose-Response Relationship, Drug , Drug Administration Schedule , Humans , Male , Polypharmacy , Tablets
7.
Andrologia ; 50(7): e13024, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29665107

ABSTRACT

Klinefelter syndrome is a condition in which a male patient has one Y chromosome and one or more extra X chromosomes. It is the most common sex chromosome disorder. Klinefelter syndrome is distinguished by many clinical features, such as infertility, high gonadotropin and low testosterone levels, increased height, and sparse body and facial hair. We report the case of a 32-year-old man who visited our hospital complaining of male infertility. Semen analysis showed azoospermia, and chromosomal analysis revealed a 47,XY,i(X)(q10) karyotype, which is a rare variant of Klinefelter syndrome. No spermatozoon was found on microdissection testicular sperm extraction, and the testis biopsy histology showed only Sertoli cells and hyalinised seminiferous tubules. 47,XY, i(X)(q10) has an additional isochromosome made of the long arm of the X chromosome, which shares some features of classical Klinefelter syndrome in many aspects, but patients are usually shorter than average height and have normal intelligence. In addition, to the best of our knowledge, no successful sperm extractions from 47,XY, i(X)(q10) patients were reported in the literature. The reports of patients who have undergone microdissection testicular sperm extraction are very rare. Further reports and studies of this chromosomal abnormality are needed.


Subject(s)
Azoospermia/genetics , Chromosome Aberrations , Chromosomes, Human, Y/genetics , Klinefelter Syndrome/genetics , Adult , Azoospermia/diagnosis , Azoospermia/pathology , Biopsy , Humans , Karyotype , Karyotyping , Klinefelter Syndrome/diagnosis , Klinefelter Syndrome/pathology , Male , Testis/pathology
8.
Eur J Neurol ; 25(2): 313-319, 2018 02.
Article in English | MEDLINE | ID: mdl-29078025

ABSTRACT

BACKGROUND AND PURPOSE: The present study was conducted to accurately determine the presence of mild cognitive impairment, which is often difficult to evaluate using only simple tests. Our approach focused on discrepancy analysis of fluid intelligence relative to crystallized intelligence using internationally recognized neuropsychological tests. METHODS: One-hundred and five patients diagnosed with asymptomatic carotid artery stenosis were assessed. The neuropsychological tests included the two subtests (information and picture completion) of Wechsler Adult Intelligence Scale-Revised (WAIS-R-two-subtests): crystallized intelligence tests and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) (immediate memory, visuospatial/constructional, language, attention, delayed memory and total score) as fluid intelligence tests. Discrepancy analysis was used to assess cognitive impairment. The score for RBANS was subtracted from the score for WAIS-R-two-subtests, and if the score difference was greater than the 5% confidence limit for statistical significance, it was defined as a decline in cognitive function. RESULTS: The WAIS-R-two-subsets was within normal limits when compared with the standardized values. However, all RBANS domains showed significant declines. Frequencies of decline in each RBANS domain were as follows: 69 patients (66%) in immediate memory, 26 (25%) in visuospatial/constructional, 54 (51%) in language, 63 (60%) in attention, 54 (51%) in delayed memory and 78 (74%) in the total score. Moreover, 99 patients (94%) showed decline in at least one RBANS domain. CONCLUSIONS: Cognitive function is only preserved in a few patients with asymptomatic carotid artery stenosis. Mild cognitive impairment can be precisely detected by performing the discrepancy analysis between crystallized and fluid intelligence tests.


Subject(s)
Carotid Stenosis/complications , Cognitive Dysfunction/diagnosis , Data Interpretation, Statistical , Intelligence Tests , Neuropsychological Tests , Aged , Aged, 80 and over , Cognitive Dysfunction/etiology , Female , Humans , Male , Middle Aged
9.
J Nanobiotechnology ; 14(1): 74, 2016 Nov 03.
Article in English | MEDLINE | ID: mdl-27809857

ABSTRACT

BACKGROUND: The field of structural dynamics of cytoskeletons in living cells is gathering wide interest, since better understanding of cytoskeleton intracellular organization will provide us with not only insights into basic cell biology but may also enable development of new strategies in regenerative medicine and cancer therapy, fields in which cytoskeleton-dependent dynamics play a pivotal role. The nanoneedle technology is a powerful tool allowing for intracellular investigations, as it can be directly inserted into live cells by penetrating through the plasma membrane causing minimal damage to cells, under the precise manipulation using atomic force microscope. Modifications of the nanoneedles using antibodies have allowed for accurate mechanical detection of various cytoskeletal components, including actin, microtubules and intermediate filaments. However, successful penetration of the nanoneedle through the plasma membrane has been shown to vary greatly between different cell types and conditions. In an effort to overcome this problem and improve the success rate of nanoneedle insertion into the live cells, we have focused here on the fluidity of the membrane lipid bilayer, which may hinder nanoneedle penetration into the cytosolic environment. RESULTS: We aimed to reduce apparent fluidity of the membrane by either increasing the approach velocity or reducing experimental temperatures. Although changes in approach velocity did not have much effect, lowering the temperature was found to greatly improve the detection of unbinding forces, suggesting that alteration in the plasma membrane fluidity led to increase in nanoneedle penetration. CONCLUSIONS: Operation at a lower temperature of 4 °C greatly improved the success rate of nanoneedle insertion to live cells at an optimized approach velocity, while it did not affect the binding of antibodies immobilized on the nanoneedle to vimentins for mechanical detection. As these experimental parameters can be applied to various cell types, these results may improve the versatility of the nanoneedle technology to other cell lines and platforms.


Subject(s)
Antibodies, Immobilized/chemistry , Cytoskeletal Proteins/analysis , Nanotechnology/instrumentation , Single-Cell Analysis/instrumentation , Antibodies, Immobilized/metabolism , Cytoskeletal Proteins/chemistry , Cytoskeletal Proteins/metabolism , HeLa Cells , Humans , MCF-7 Cells , Microscopy, Atomic Force , Microscopy, Fluorescence , Needles , Single-Cell Analysis/methods
10.
Eur Cell Mater ; 30: 187-99, 2015 Sep 28.
Article in English | MEDLINE | ID: mdl-26412389

ABSTRACT

Odontogenic ameloblast-associated (ODAM) belongs to the secretory calcium-binding phosphoprotein (SCPP) gene cluster. It is expressed by the epithelial ameloblasts during the accrued mineralisation of enamel and by cells of the junctional epithelium (JE), a specialised portion of the gingiva that plays a critical role in periodontal health. In both cases, ODAM localises at the interface between the cells and the tooth surface. It is also present among the cells of the JE, and is distinctively highly expressed in many epithelial tumours. ODAM has been proposed to be a matricellular protein implicated in the adhesion of epithelial cells to tooth surfaces, and possibly in mediating cell status. To gain further understanding of the role of ODAM, we have created an Odam knockout (KO) mouse by deleting coding exons 2-6. Inactivation of the gene was verified by Southern blot, PCR, real-time qPCR and loss of immunostaining for the protein. Young Odam KO mice showed no readily apparent phenotype. No significant differences were observed in enamel volume and density, rod-interrod organisation, and its attrition. However, in older animals, the JE presented some detachment, an increase in inflammatory infiltrate, and apical down-growth. In addition, its regeneration was delayed following a gingivectomy challenge. Our results indicate that inactivation of Odam expression has no dramatic consequence on enamel but the phenotype in older animals replicates some JE changes seen during human periodontal disease. Altogether, our results suggest that ODAM plays a role in maintaining integrity of the JE.


Subject(s)
Ameloblasts/cytology , Epithelial Attachment/cytology , Epithelial Cells/cytology , Odontogenesis/genetics , Regeneration/genetics , Wound Healing , Animals , Gingiva/cytology , Mice, Knockout , Regeneration/physiology
11.
Eur J Surg Oncol ; 41(11): 1515-21, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26210654

ABSTRACT

AIM: This study aimed to investigate the clinicopathological predictors of survival in patients with intrahepatic cholangiocarcinoma, mass-forming type (ICC-MF), following curative intent hepatectomy. METHODS: Clinical characteristics and outcomes were analyzed in a series of 42 patients who underwent curative hepatectomy for ICC-MF between February 1987 and December 2012. The relationship between immunohistochemical expression profiles of mucin (MUC) core proteins (MUC2, MUC5AC, and MUC6) and surgical outcomes was examined. RESULTS: The overall median follow-up period was 2.6 years (0.2-17.9). Bile duct reconstruction (p = 0.017), lymph node metastasis (p = 0.049), maximal mass diameter ≥5.0 cm (p = 0.002), and MUC5AC expression (p = 0.003) were identified as significant adverse predictors of overall survival by univariate analysis. Bile duct reconstruction (p = 0.048), maximal mass diameter ≥5.0 cm (p = 0.002), and MUC5AC expression (p = 0.005) were found to be independent predictors of poor prognosis by multivariate analysis. Maximal mass diameter ≥5.0 cm (p = 0.011) was found to be an independent predictor for the tumor recurrence. There was a strong correlation between MUC5AC expression and lymph node metastasis (p = 0.021). MUC6 expression was more frequent in patients with concurrent MUC5AC expression (p = 0.019). CONCLUSIONS: MUC5AC expression was significantly related to long-term prognosis and aggressive tumor development, and may be a useful prognostic marker.


Subject(s)
Bile Duct Neoplasms/metabolism , Bile Ducts, Intrahepatic , Cholangiocarcinoma/metabolism , Hepatectomy , Mucin 5AC/biosynthesis , Aged , Aged, 80 and over , Bile Duct Neoplasms/diagnosis , Bile Duct Neoplasms/surgery , Biomarkers, Tumor/biosynthesis , Cholangiocarcinoma/diagnosis , Cholangiocarcinoma/surgery , Female , Follow-Up Studies , Humans , Immunohistochemistry , Male , Middle Aged , Neoplasm Staging , Postoperative Period , Prognosis , Retrospective Studies , Time Factors , Tomography, X-Ray Computed
12.
Clin Oral Implants Res ; 26(5): 581-5, 2015 May.
Article in English | MEDLINE | ID: mdl-25040888

ABSTRACT

OBJECTIVES: To achieve ideal functional and aesthetic requirements, ridge augmentation is often required before dental implant placement. Bone augmentation (especially vertical), which normally consists of complex and invasive surgeries, still remains challenge. This study seeks to investigate the feasibility of an injectable in situ gel-forming system containing strontium hydroxyapatite (SrHA) and alginate for minimally invasive bone augmentation in a rat calvarial model. MATERIAL AND METHODS: SrHA-alginate solution was prepared by mixing SrHA powder with alginate solution (20 mg/mL) to the final concentration of 0.5% (w/v). Each animal received a 200-µL single subperiosteal injection of either SrHA-alginate solution or alginate solution. The new bone formation was assessed at 0, 4, and 8 weeks histologically and radiologically. RESULTS: The SrHA-alginate solution materials could form solid gel once injected. As such, no sutures were required to close the injection site. Significantly greater amount of new bone formation was observed in the SrHA-alginate group compared with the alginate group both by micro-CT and by histological section. The newly formed bone in the SrHA-alginate group originated both from the underlying original bone and from the elevated periosteum. A 2.3-fold increase of the vertical bone height was observed in the SrHA-alginate group compared with 1.3-fold increase in the alginate group. CONCLUSIONS: Rat calvarial bone augmentation was achieved by a single subperiosteal injection of SrHA-alginate solution without any administration of stem cells or growth factors. The in situ gel-forming material may hold potential therapeutic benefits for local bone augmentation in a minimally invasive manner.


Subject(s)
Hydroxyapatites/pharmacology , Osteogenesis/drug effects , Strontium/pharmacology , Alginates/pharmacology , Animals , Biocompatible Materials/pharmacology , Bone Regeneration/drug effects , Dental Implantation, Endosseous , Feasibility Studies , Gels , Glucuronic Acid/pharmacology , Hexuronic Acids/pharmacology , Models, Animal , Rats , Skull
13.
Int J Oral Maxillofac Surg ; 44(1): 90-6, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25220944

ABSTRACT

The aim of the present study was to evaluate the accuracy of a novel simulation software package (OrthoForecast) for predicting the soft tissue profile after orthognathic surgery. The study included 15 patients with facial asymmetry (asymmetry group), 15 with a skeletal class II jaw relationship (class II group), and 15 with a skeletal class III jaw relationship (class III group). Twenty-four feature points were digitized, and the distances between points on the predicted and actual postoperative images were compared. Thirty-seven calibrated evaluators also graded the similarity of the predicted images compared to the actual postoperative photographs. Comparisons between the predicted and actual postoperative images revealed that the mean difference between feature points was 3.1 ± 1.4 mm for the frontal images and 2.9 ± 0.8 mm for the lateral images in the asymmetry group; 2.7 ± 0.9 and 2.1 ± 1.6 mm, respectively, in the class II group; and 1.8 ± 1.2 and 1.7 ± 1.0 mm, respectively, in the class III group. More than half of the evaluators assessed the predicted images as similar to the actual postoperative images in all groups. In conclusion, OrthoForecast can be regarded as useful, accurate, and reliable software to predict soft tissue changes after orthognathic surgery.


Subject(s)
Esthetics , Facial Asymmetry/surgery , Malocclusion, Angle Class III/surgery , Malocclusion, Angle Class II/surgery , Orthognathic Surgical Procedures , Software , Adult , Algorithms , Anatomic Landmarks , Cephalometry , Computer Simulation , Facial Asymmetry/diagnostic imaging , Female , Humans , Male , Malocclusion, Angle Class II/diagnostic imaging , Malocclusion, Angle Class III/diagnostic imaging , Osteotomy , Photography , Predictive Value of Tests , Radiography
14.
Transplant Proc ; 46(3): 982-5, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24767397

ABSTRACT

Maintaining hepatic inflow and appropriate venous drainage is important for maximizing the capacity of the retrieved graft in liver transplantation. Here, we report a successful case of multiple hepatic vein (HV) reconstruction using an all-in-one sleeve patch graft of the autologous great saphenous vein to ensure adequate blood flow through the HV. A patient with hepatocellular carcinoma caused by hepatitis C virus-induced cirrhosis underwent living donor liver transplantation using a right lobe graft. A preoperative dynamic computed tomography scan and intraoperative findings revealed that the graft had three middle HV tributaries, a superficial vein, segment VIII HV (V8), and segment V HV (V5). The openings of the superficial vein and V8 were located very close to that of the right hepatic vein (RHV) in the cutting surface. Each HV had significant diameter and drainage territory requiring reconstruction. An autologous great saphenous vein was used to create a sleeve patch to incorporate the close-packed HV openings. The autologous sleeve patch graft was sutured to the openings of the RHV and the superficial vein and the hole created on the sleeve patch graft was anastomosed to the openings of V8 directly on the back table to create an all-in-one sleeve patch. For the V5 reconstruction, the recipient's intrahepatic portal vein graft was used to create an interpositional conduit from the recipient's V5 to the inferior vena cava. The postoperative course was uneventful and postoperative studies revealed good graft function with excellent blood flow in the HV.


Subject(s)
Hepatic Veins/surgery , Liver Transplantation/methods , Living Donors , Vascular Surgical Procedures , Aged , Humans , Male
15.
Phys Rev Lett ; 112(3): 034802, 2014 Jan 24.
Article in English | MEDLINE | ID: mdl-24484144

ABSTRACT

A novel scheme for the focusing of high-energy leptons in future linear colliders was proposed in 2001 [P. Raimondi and A. Seryi, Phys. Rev. Lett. 86, 3779 (2001)]. This scheme has many advantageous properties over previously studied focusing schemes, including being significantly shorter for a given energy and having a significantly better energy bandwidth. Experimental results from the ATF2 accelerator at KEK are presented that validate the operating principle of such a scheme by demonstrating the demagnification of a 1.3 GeV electron beam down to below 65 nm in height using an energy-scaled version of the compact focusing optics designed for the ILC collider.

16.
Cancer Chemother Pharmacol ; 73(3): 623-30, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24477603

ABSTRACT

PURPOSE: To determine ombrabulin's maximum tolerated dose and dose recommended for Japanese patients with advanced solid tumors and to assess its antitumor activity and overall safety and pharmacokinetic profiles. METHODS: This was a multi-center, open-label, sequential-cohort, dose-escalation phase I study of ombrabulin, a vascular disrupting agent, administered once every 3 weeks. Patients were treated with 15.5, 25, 35, or 50 mg/m(2) ombrabulin over a 30-min intravenous infusion. The recommended dose was the highest dose at which <33 % of all evaluable patients experienced dose-limiting toxicities (DLTs) during the first treatment cycle or 50 mg/m(2) (recommended in Caucasian patients) if the previous definition was not met. RESULTS: Fifteen patients were treated. No DLT occurred with 15.5, 25, or 35 mg/m(2) ombrabulin. In the 50 mg/m(2) group, one patient had Grade 3 lymphopenia, and another experienced Grade 2 hypertension and Grade 3 diarrhea judged as DLTs. The most frequent related adverse events in this group were diarrhea, nausea, and hypertension. Two patients had Grade 3 anemia, one at the 15.5 mg/m(2) and the other at the 50 mg/m(2). No AEs necessitating dose reduction or Grade 4 AEs were observed. Overall, five patients had stable disease. Pharmacokinetic parameters were comparable to those in non-Japanese patients. CONCLUSIONS: Ombrabulin treatment once every 3 weeks was well tolerated in Japanese patients with advanced solid tumors. The dose recommended is 50 mg/m(2), as in Caucasian patients. The safety and pharmacokinetic profiles were comparable between Japanese and Caucasian patients (funded by Sanofi; ClinicalTrials.gov number, NCT00968916).


Subject(s)
Neoplasms/drug therapy , Serine/analogs & derivatives , Asian People , Cohort Studies , Dose-Response Relationship, Drug , Drug Administration Schedule , Female , Humans , Infusions, Intravenous , Male , Maximum Tolerated Dose , Middle Aged , Neoplasms/blood supply , Neoplasms/metabolism , Neoplasms/pathology , Neovascularization, Pathologic/drug therapy , Serine/administration & dosage , Serine/adverse effects , Serine/pharmacokinetics
17.
J Oral Rehabil ; 40(4): 239-46, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23398635

ABSTRACT

Parafunctional habits, such as prolonged clenching and bruxism, have been associated with dysfunctional overloading in the temporomandibular joint (TMJ). In this study, stress distributions in the TMJ were analysed during prolonged clenching, using three-dimensional finite element (FE) models of the TMJ with and without disc displacement. The aim of this study was to investigate stress distribution of the cartilaginous tissues in the TMJ with and without disc displacement. Finite element models were developed on the basis of magnetic resonance images from two subjects with and without anterior disc displacement. Condylar movements recorded during a 5-min clenching were used as the loading condition for stress analysis. In the asymptomatic model, the highest von Mises stresses were located in the lateral area (4·91 MPa) of the disc surfaces, and after 5-min clenching, the higher stresses were still located at the lateral area (3·65 MPa). In all the cartilaginous tissues, 30-50% of stress reduction occurred during 5-min clenching. In contrast, the von Mises stress in the cartilaginous tissues of the symptomatic model with disc displacement was markedly lower, compared with the asymptomatic model. However, in the condylar cartilage, stress relaxation during clenching was not recognised. Furthermore, relatively high stresses were observed in the retrodiscal tissues throughout clenching. The present results indicate that disc position could be involved in the stress distribution of the TMJ components during prolonged clenching.


Subject(s)
Finite Element Analysis , Joint Dislocations/physiopathology , Muscle Contraction/physiology , Temporomandibular Joint Disc/physiopathology , Temporomandibular Joint Disorders/physiopathology , Temporomandibular Joint/physiopathology , Adult , Algorithms , Biomechanical Phenomena , Cartilage, Articular/pathology , Cartilage, Articular/physiopathology , Computer Simulation , Elastic Modulus , Female , Friction , Humans , Imaging, Three-Dimensional/methods , Joint Dislocations/pathology , Magnetic Resonance Imaging , Mandibular Condyle/pathology , Mandibular Condyle/physiopathology , Masticatory Muscles/physiopathology , Models, Biological , Stress, Mechanical , Temporal Bone/pathology , Temporal Bone/physiopathology , Temporomandibular Joint/pathology , Temporomandibular Joint Disc/pathology , Temporomandibular Joint Disorders/pathology , Young Adult
18.
Phys Chem Chem Phys ; 15(5): 1518-25, 2013 Feb 07.
Article in English | MEDLINE | ID: mdl-23238425

ABSTRACT

Solutions of Nafion® with an ion exchange capacity (IEC) of 0.91 meq g(-1), which are on the verge of the formation of SO(3)H nanoclusters, were spin coated on silicon (Si), glassy carbon (GC) and platinum/silicon (Pt/Si) substrates to form films of up to 256 nm thickness. Nanostructure of the films was studied using Doppler broadening of annihilation radiation (DBAR), positron annihilation lifetime (PAL), X-ray photoelectron spectroscopy (XPS), an atomic force microscope (AFM) and contact angle measurements. Contact angles as low as 10 degrees indicate that the surface of dry ultrathin Nafion® films on Si is highly hydrophilic. XPS data of 10 nm thick, ultrathin film on Si show that oxygen concentration is enhanced and the SO(3)H group concentration, in other words, IEC on the surface is much higher than other films. The S parameter measured by DBAR of an ultrathin Nafion® film on Si is much higher than that of the films on the other substrates. We consider that a large number of hydrophilic, reversed micelle like SO(3)H groups are on the surface of the ultrathin Nafion® film on Si but not on the surface of other films. Positrons implanted into the film are trapped by the SO(3)H clusters, annihilating with the electrons of oxygen and exhibit the high S parameter. The SO(3)H concentration on the surface of thin Nafion® films on GC and Pt/Si substrates may not be so high as the threshold for the formation of a large number of SO(3)H clusters. Positrons implanted into the films annihilate mostly with fluorine atoms, resulting in a low S parameter. The film-substrate interaction plays an essential role in nanostructuring of Nafion® thin films, which may also be the case for Nafion® on the catalysts of polymer electrolyte fuel cells.

19.
J Periodontal Res ; 47(2): 180-7, 2012 Apr.
Article in English | MEDLINE | ID: mdl-21972924

ABSTRACT

BACKGROUND AND OBJECTIVE: The tooth root is one of the critical parts to maintain tooth function; however, the molecular mechanisms of root development remain unknown. We aimed to identify specific factors for root morphogenesis using a newly developed experimental system. MATERIAL AND METHODS: Tentative cementoblasts and periodontal ligament cells from mouse mandibular molars were isolated using laser capture microdissection. More than 500 cementoblasts and periodontal ligament cells were separately captured. After RNA extraction and amplification, mRNA expression in isolated cementoblasts was compared with that of periodontal ligament cells by cDNA microarray analysis. Then, putative cementoblast-specific genes were subjected to in situ hybridization analysis to confirm the results in mouse mandible. RESULTS: Approximately 2000 genes were differentially expressed between these tissues. Among those genes, zinc finger helicase (ZFH), also termed chromodomain-helicase-DNA-binding protein 3 (Chd3), was one of the highly expressed transcripts in tentative cementoblasts. In situ hybridization revealed that ZFH/Chd3 was strongly expressed in Hertwig's epithelial root sheath rather than in cementum. Moreover, its expression disappeared when root formation was advanced in the first molar. In contrast, Chd3 was continuously expressed in dental epithelial cells of the cervical loop, in which root extension is never terminated. CONCLUSION: These results suggest that ZFH/Chd3 might play an important role in tooth root development and subsequent cementogenesis.


Subject(s)
DNA Helicases/genetics , DNA-Binding Proteins/genetics , Odontogenesis/genetics , Tooth Root/growth & development , Ameloblasts/physiology , Animals , Cell Culture Techniques , Chromatin Assembly and Disassembly/genetics , Dental Cementum/physiology , Enamel Organ/growth & development , Epithelial Cells/physiology , Gene Expression Profiling , Gene Expression Regulation, Developmental/genetics , Incisor/growth & development , Laser Capture Microdissection , Male , Mandible/cytology , Mice , Mice, Inbred ICR , Molar/growth & development , Morphogenesis/genetics , Nucleic Acid Hybridization , Oligonucleotide Array Sequence Analysis , Periodontal Ligament/cytology , Tooth Germ/growth & development
20.
Curr Neuropharmacol ; 9(1): 169-75, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21886585

ABSTRACT

Experimental studies have demonstrated that not only dopaminergic signaling but also glutamatergic/NMDA receptor signaling play indispensable roles in the development of methamphetamine psychosis. Our recent genetic studies provided evidence that genetic variants of glutamate-related genes such as DTNBP1, GLYT1, and G72, which are involved in glutamate release and regulation of co-agonists for NMDA receptors, conferred susceptibility to methamphetamine psychosis. Serine racemase converts l-serine to d-serine, which is an endogenous co-agonist for NMDA receptors. Three single nucleotide polymorphisms (SNPs) in the promoter region of the serine racemase gene (SRR), rs224770, rs3760229, and rs408067, were proven to affect the transcription activity of SRR. Therefore, we examined these SNPs in 225 patients with methamphetamine psychosis and 291 age- and sex-matched controls. There was no significant association between methamphetamine psychosis and any SNP examined or between the disorder and haplotypes comprising the three SNPs. However, rs408067 was significantly associated with the prognosis for methamphetamine psychosis and multi-substance abuse status. The patients with C-positive genotypes (CC or CG) of rs408067 showed better prognosis of psychosis after therapy and less abuse of multiple substances than the patients with GG genotypes. Because the C allele of rs408067 reduces the expression of SRR, a lower d-serine level or reduced NMDA receptor activation may affect the prognosis of methamphetamine psychosis and multiple substance abuse. Our sample size is, however, not large enough to eliminate the possibility of a type I error, our findings must be confirmed by replicate studies with larger samples.

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