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1.
Lab Chip ; 16(4): 668-78, 2016 Feb 21.
Article in English | MEDLINE | ID: mdl-26725379

ABSTRACT

The miniaturization of integrated fluidic processors affords extensive benefits for chemical and biological fields, yet traditional, monolithic methods of microfabrication present numerous obstacles for the scaling of fluidic operators. Recently, researchers have investigated the use of additive manufacturing or "three-dimensional (3D) printing" technologies - predominantly stereolithography - as a promising alternative for the construction of submillimeter-scale fluidic components. One challenge, however, is that current stereolithography methods lack the ability to simultaneously print sacrificial support materials, which limits the geometric versatility of such approaches. In this work, we investigate the use of multijet modelling (alternatively, polyjet printing) - a layer-by-layer, multi-material inkjetting process - for 3D printing geometrically complex, yet functionally advantageous fluidic components comprised of both static and dynamic physical elements. We examine a fundamental class of 3D printed microfluidic operators, including fluidic capacitors, fluidic diodes, and fluidic transistors. In addition, we evaluate the potential to advance on-chip automation of integrated fluidic systems via geometric modification of component parameters. Theoretical and experimental results for 3D fluidic capacitors demonstrated that transitioning from planar to non-planar diaphragm architectures improved component performance. Flow rectification experiments for 3D printed fluidic diodes revealed a diodicity of 80.6 ± 1.8. Geometry-based gain enhancement for 3D printed fluidic transistors yielded pressure gain of 3.01 ± 0.78. Consistent with additional additive manufacturing methodologies, the use of digitally-transferrable 3D models of fluidic components combined with commercially-available 3D printers could extend the fluidic routing capabilities presented here to researchers in fields beyond the core engineering community.

3.
Dentomaxillofac Radiol ; 40(2): 96-101, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21239572

ABSTRACT

OBJECTIVES: Videofluorography (VF) is useful for diagnosing dysphagia; however, few reports have investigated appropriate effective doses for VF. The present study aimed to estimate the effective radiation dose in VF for diagnosis of dysphagia. METHODS: Radiation doses to tissues and organs were measured using the anthropomorphic RANDO woman phantom as an equivalent to the human body. Effective doses were estimated according to the recommendations of the International Commission on Radiological Protection (ICRP) 60 in 1990 and IRCP 103 in 2007. The tissues measured were those recommended by ICRP 60 and ICRP 103 including gonads (ovaries and testes), red bone marrow and tissues in which excessive radiation commonly causes malignant tumours including lung, thyroid gland, stomach, large intestine, liver, oesophagus, bladder, breast, bone marrow, skin, brain and salivary gland. Skin dose was also measured using thermoluminescent dosimeters. RESULTS: Using ICRP 103, the effective dose was estimated as 118.1 µSv at a tube voltage of 50 kV and 82.4 µSv at 45 kV. However, using ICRP 60 the effective dose for 1 min of VF was estimated at 62.4 µSv and 47.2 µSv under the same exposure conditions. CONCLUSIONS: Using ICRP 103, the effective dose for VF per examination at a total estimation time of 1 min was estimated as approximately 2.5-8.3 times that observed for digital panoramic radiography and 1/12 to 3 times depending on the measurement device for cone beam CT (CBCT). This value can be decreased in the future using a smaller irradiation field and decreased time for examination in VF in the future.


Subject(s)
Deglutition Disorders/diagnostic imaging , Phantoms, Imaging , Photofluorography/methods , Humans , Radiation Dosage , Thermoluminescent Dosimetry , Videotape Recording
4.
Br J Sports Med ; 44(12): 856-61, 2010 Sep.
Article in English | MEDLINE | ID: mdl-19042919

ABSTRACT

BACKGROUND: Although high prevalence of anterior cruciate ligament injuries (ACL) in judokas has been reported, there has been very little research concerning events preceding the injury. OBJECTIVE: To determine the common situations and mechanisms of ACL injury in judo. METHODS: A total of 43 cases of ACL injuries that had occurred during judo competition or practice were investigated, using questionnaires with interviews conducted by a single certified athletic trainer who has 20 years of judo experience to obtain information regarding the situation and mechanism in which the ACL injury occurred. RESULTS: The number of ACL injuries when the participant's grip style was different from the style of the opponent (ie, kenka-yotsu style) (28 cases) was significantly greater than when the participant's grip style was the same as that of the opponent (ie, ai-yotsu style) (15 cases; p<0.001). The number of ACL injuries was significantly higher when the participant was attacked by the opponent than when counterattacked or when attempting the attack (p<0.001). In addition, being attacked with osoto-gari was revealed as the leading cause of ACL injury incidence among the participants (16.8%). CONCLUSIONS: Grip style may be associated with ACL injury occurrence in judo. In addition, direct contact due to the opponent's attack may be a common mechanism for ACL injuries in judo.


Subject(s)
Anterior Cruciate Ligament Injuries , Martial Arts/injuries , Adolescent , Female , Humans , Male , Postural Balance/physiology , Posture/physiology , Retrospective Studies , Young Adult
5.
Dentomaxillofac Radiol ; 38(2): 79-85, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19176649

ABSTRACT

OBJECTIVES: Volumetric CT using a cone beam has been developed by several manufacturers for dentomaxillofacial imaging. The purpose of this study was to measure doses for implant planning with cone beam volumetric imaging (CBVI) in comparison with conventional multidetector CT (MDCT). METHODS: The two CBVI systems used were a 3D Accuitomo (J. Morita), including an image-intensifier type (II) and a flat-panel type (FPD), and a CB MercuRay (Hitachi). The 3D Accuitomo operated at 80 kV, 5 mA and 18 s. The CB MercuRay operated at 120 kV, 15 mA, 9.8 s. The MDCT used was a HiSpeed QX/i (GE), operated at 120 kV, 100 mA and 0.7 s, and its scan length was 77 mm for both jaws. Measurement of the absorbed tissue and organ doses was performed with an Alderson phantom, embedding the radiophotoluminescence glass dosemeter into the organs/tissues. The values obtained were converted into the absorbed dose. The effective dose as defined by the International Commission on Radiological Protection was then calculated. RESULTS: The absorbed doses of the 3D Accuitomo of the organs in the primary beam ranged from 1-5 mGy, and were several to ten times lower than other doses. The effective dose of the 3D Accuitomo ranged from 18 muSv to 66 muSv, and was an order of magnitude smaller than the others. In conclusion, these results show that the dose in the 3D Accuitomo is lower than the CB MercuRay and much less than MDCT.


Subject(s)
Cone-Beam Computed Tomography/methods , Dental Implants , Head/radiation effects , Patient Care Planning , Radiation Dosage , Abdomen/radiation effects , Bone Marrow/radiation effects , Brain/radiation effects , Cone-Beam Computed Tomography/instrumentation , Humans , Image Processing, Computer-Assisted/instrumentation , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Jaw/radiation effects , Lens, Crystalline/radiation effects , Mandible/radiation effects , Neck/radiation effects , Pelvis/radiation effects , Phantoms, Imaging , Salivary Glands/radiation effects , Skin/radiation effects , Thermoluminescent Dosimetry/instrumentation , Thorax/radiation effects , Thyroid Gland/radiation effects , Tomography Scanners, X-Ray Computed , Tomography, X-Ray Computed/instrumentation , Tomography, X-Ray Computed/methods
6.
Radiat Prot Dosimetry ; 128(3): 343-50, 2008.
Article in English | MEDLINE | ID: mdl-18337296

ABSTRACT

Surface dose monitoring in patients and physicians during 29 uterine artery embolisation (UAE) procedures was performed using photoluminescence dosemeters and thermo-luminescence dosemeters. Organ or tissue doses were measured with an anthropomorphic phantom using UAE exposure conditions averaged from the 29 cases, and effective doses were estimated for the patient. Entrance surface dose of the patients at the maximum dose position ranged from 121.5 to 1650 mGy. Estimated doses ranged from 3.16 to 43 mGy for the ovary and from 3.8 to 51.8 mGy for the uterus. The effective dose was 1.09-14.8 mSv. Monitored doses on the body surface of physicians were relatively high in the upper arm (5.41+/-1.52 to 163+/-17.25 microGy) and the hand and fingers (0.85+/-1.18 to 222+/-16.4 microGy).


Subject(s)
Embolization, Therapeutic , Fluoroscopy , Occupational Exposure , Ovary/radiation effects , Physicians , Radiography, Interventional , Thermoluminescent Dosimetry , Uterus/blood supply , Arteries , Female , Humans , Radiation Dosage , Uterus/radiation effects
7.
J Sports Med Phys Fitness ; 46(3): 425-30, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16998447

ABSTRACT

AIM: The purpose of this study was to investigate the relationship between the influence of music on RPE during sub-maximal exercise and on the autonomic nervous system before and after sub-maximal exercise. METHODS: Heart rate (HR), HR variability (HRV) and rates of physical fatigue (RPE) during exercise at 60% and at 40% VO2max with and without music were measured. The exercise protocol consisted of a 30-min seated rest (control) period followed by a 30-min submaximal cycling exercise and a 35-min recovery period. Autonomic-nervous activity was measured before and after exercise. During exercise, RPE was recorded every 3 min and HR was recorded for every minute. RESULTS: Although RPE did not differ during exercise at 60% VO2max, this value was lower during exercise at 40% VO2max in the presence, than in the absence of a favorite piece music (P < 0.05). HR, HFA and LFA/HFA of HRV significantly differed with exercise intensity in the absence (P < 0.05), but not in the presence of music. CONCLUSIONS: These findings suggested that music evokes a ''distraction effect'' during low intensity exercise, but might not influence the autonomic nervous system. Therefore, when jogging or walking at comparatively low exercise intensity, listening to a favorite piece of music might decrease the influence of stress caused by fatigue, thus increasing the ''comfort'' level of performing the exercise.


Subject(s)
Autonomic Nervous System/physiology , Exercise/physiology , Heart Rate/physiology , Muscle Fatigue/physiology , Music , Physical Exertion/physiology , Adult , Analysis of Variance , Exercise Test , Exercise Tolerance/physiology , Humans , Male , Oxygen Consumption/physiology , Reference Values
8.
Dentomaxillofac Radiol ; 35(3): 152-7, 2006 May.
Article in English | MEDLINE | ID: mdl-16618847

ABSTRACT

OBJECTIVES: We compared the diagnostic reliability of cone beam computed tomography (3DX) and helical computed tomography (helical CT) for the detection of osseous abnormalities of the mandibular condyle, using macroscopic observations as the gold standard. METHODS: Twenty-one temporomandibular joint autopsy specimens underwent imaging with 3DX and helical CT. The specimens were macroscopically evaluated for cortical erosion or osteophytosis and sclerosis. The images were independently assessed for the same osseous abnormalities. Observations with the two imaging modalities were compared with the macroscopic observations using the McNemar test. RESULTS: According to the macroscopic observations, 10 of the 21 mandibular condyles and one fossa showed osseous abnormalities. 3DX detected abnormalities in eight of these condyles and helical CT identified abnormalities in seven, giving a sensitivity of 0.80 for 3DX and 0.70 for helical CT. The specificity of the condyle assessment was 1.0 for both 3DX and helical CT and hence, the accuracy was 0.90 and 0.86, respectively. No significant differences were detected between the 3DX and helical CT for assessment of osseous abnormalities of the mandibular condyle (P=0.286). CONCLUSIONS: The cone beam CT equipment 3DX is a dose-effective and a cost-effective alternative to helical CT for the diagnostic evaluation of osseous abnormalities of the mandibular condyle.


Subject(s)
Mandibular Condyle/diagnostic imaging , Mandibular Diseases/diagnostic imaging , Radiography, Dental/methods , Temporomandibular Joint Disorders/diagnostic imaging , Temporomandibular Joint/diagnostic imaging , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Cadaver , Chi-Square Distribution , Female , Humans , Male , Mandibular Condyle/pathology , Middle Aged , Osteoarthritis/diagnostic imaging , Osteosclerosis/diagnostic imaging , Radiography, Dental/instrumentation , Sensitivity and Specificity , Temporomandibular Joint/pathology , Tomography, Spiral Computed/instrumentation , Tomography, X-Ray Computed/instrumentation
9.
Int J Soc Psychiatry ; 51(1): 83-96, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15864978

ABSTRACT

OBJECTIVES: The study was aimed at evaluating facets of psychiatric inpatient care of patients with schizophrenia in a German and a Japanese hospital. METHODS: Based upon a sample of 865 inpatients of the Psychiatric State Hospital Regensburg (BKR) and 50 inpatients of the Tokyo Women's Medical University (TWMU) admitted in 1997, data of a psychiatric basic documentation system (BADO) were analysed with regard to essential process and outcome indicators. RESULTS: Despite dissimilarities between both patient groups with respect to schizophrenic subtype, duration of illness as well as severity of illness and psychosocial functioning, the differences regarding therapeutic treatment and outcome were marked. In 1997, the rate of atypical neuroleptics was 18% at the BKR and 12% at the TWMU. Inpatients of the TWMU were given benzodiazepines and anticholinergic drugs significantly more frequently. Male patients of the TWMU showed more severe side-effects. Psychotherapy and sociotherapy were less frequently applied at the TWMU. Although the patient groups did not differ with regard to suicidal behaviour and overt aggressions during hospitalisation, we found a higher rate of mechanical restraints at the TWMU. In 1997, the average length of stay was significantly higher at the TWMU (153 days) than at the BKR (52 days), but inpatients of the TWMU improved only slightly better with regard to global psychosocial functioning (GAF) and severity of illness (CGI). CONCLUSIONS: The revealed differences in treatment are likely due to differences in service provision and national practices in Germany and Japan and provide clues for quality improvements. The BADO is a useful tool for continuous quality management and an ongoing international exchange concerning psychiatric inpatient care.


Subject(s)
Cross-Cultural Comparison , Cultural Diversity , Hospitalization/statistics & numerical data , Hospitals, Psychiatric , Hospitals, State , Schizophrenia/therapy , Schizophrenic Psychology , Adult , Aggression/psychology , Antipsychotic Agents/administration & dosage , Antipsychotic Agents/adverse effects , Benzodiazepines/administration & dosage , Benzodiazepines/adverse effects , Cholinergic Antagonists/administration & dosage , Cholinergic Antagonists/adverse effects , Drug Utilization/statistics & numerical data , Female , Germany , Hospitals, Psychiatric/statistics & numerical data , Hospitals, State/statistics & numerical data , Hospitals, University/statistics & numerical data , Humans , Japan , Male , Middle Aged , Outcome Assessment, Health Care , Restraint, Physical/statistics & numerical data , Schizophrenia/diagnosis , Sex Factors , Suicide/statistics & numerical data
10.
J Int Med Res ; 33(2): 207-14, 2005.
Article in English | MEDLINE | ID: mdl-15790132

ABSTRACT

The effects of adiponectin replacement therapy on myocardial damage were studied in leptin-deficient (OB) mice with acute viral myocarditis. Encephalomyocarditis virus was injected intraperitoneally into OB and wild-type (WT) mice. One subgroup of OB mice received no intervention and another subgroup received daily adiponectin replacement, simultaneously with viral inoculation. Differences in heart weight, cardiac histological score, numbers of infiltrating or apoptotic cells in the myocardium and the immunoreactivity of adiponectin receptors in myocytes were determined. The reactivity of adiponectin receptor 1 in myocytes from OB mice on day 4 and day 8 after viral inoculation was significantly decreased compared with that in myocytes from WT mice; the OB mice also had elevated cardiac weights and severe inflammatory myocardial damage. Adiponectin replacement in OB mice inhibited the development of severe myocarditis by augmenting myocyte adiponectin receptor 1 reactivity. Exogenously administered adiponectin may inhibit the progression of viral myocarditis through binding to the adiponectin receptor 1 in leptin-deficient conditions.


Subject(s)
Encephalomyocarditis virus/metabolism , Intercellular Signaling Peptides and Proteins/administration & dosage , Leptin/metabolism , Myocarditis/therapy , Myocarditis/virology , Myocardium/pathology , Adiponectin , Animals , Apoptosis , Body Weight , Disease Progression , Genetic Therapy , Heart/physiology , Heart/virology , Intercellular Signaling Peptides and Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Muscle Cells/metabolism , Myocardium/metabolism , Organ Size , Protein Binding , Receptors, Adiponectin , Receptors, Cell Surface/metabolism , Receptors, Leptin , Time Factors
11.
J Int Med Res ; 33(2): 236-44, 2005.
Article in English | MEDLINE | ID: mdl-15790136

ABSTRACT

This study determined the presence of adiponectin, T-cadherin (an adiponectin receptor) and tumour necrosis factor-alpha (TNF-alpha) in damaged myocytes from autopsied patients with acute or old myocardial infarction (MI) or dilated cardiomyopathy (DCM), using immunohistochemical staining. The enrolled patients included eight with acute MI, six with old MI and seven with DCM. Four autopsied individuals with no cardiac lesions were also enrolled as controls. Adiponectin and TNF-alpha were not observed in normal myocytes from control subjects, but T-cadherin was weakly detected. Immunoreactivity for adiponectin and T-cadherin was observed at the periphery of damaged myocytes from MI and DCM patients; intracellular reactivity for TNF-alpha was also seen. There were no statistically significant differences in the degree of reactivity for each molecule in the myocytes between the MI and DCM patients. These results suggest that the presence of adiponectin and TNF-alpha in damaged myocytes may contribute to the processes of myocardial injury occurring in MI and DCM.


Subject(s)
Cadherins/biosynthesis , Intercellular Signaling Peptides and Proteins/biosynthesis , Myocytes, Cardiac/metabolism , Tumor Necrosis Factor-alpha/biosynthesis , Adiponectin , Adolescent , Adult , Aged , Aged, 80 and over , Autopsy , Cardiomyopathies/pathology , Cardiomyopathy, Dilated/pathology , Female , Humans , Immunohistochemistry , Intercellular Signaling Peptides and Proteins/metabolism , Male , Middle Aged , Myocardial Infarction/metabolism , Myocardium/pathology
12.
Appl Microbiol Biotechnol ; 68(2): 198-202, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15717173

ABSTRACT

A chlorogenate hydrolase (EC 3.1.1.42) synthesized 2-phenylethyl caffeate (2-CAPE) from 5-chlorogenic acid (5-CQA) and 2-phenylethyl alcohol (2-PA) (by transesterification), from 5-CQA and 2-phenylethyl bromide (2-PBr) (by substitution of bromine), and from caffeic acid (CA) and 2-PA or 2-PBr (by condensation) as well as hydrolysis of 5-CQA. Some reaction conditions including pH, temperature, substrate and solvent concentrates, and reaction time were optimized for the production of 2-CAPE. A maximal molar yield of 50% was achieved by transesterification, 4.7% by substitution of bromine, and 13% by condensation. Among the parameters studied for optimization, the pH of the buffer solution and concentration of 2-PA or 2-PBr affected the production of 2-CAPE. The optimum pH for the hydrolysis reaction was within the neutral range (pH 6.5), whereas the residual three reactions were only catalyzed within the acidic range (pH 3.0-4.0). The optimum concentrations of 2-PA and 2-PBr for three reactions were 5-70 vol% and no 2-CAPE was produced in the 2-PA or 2-PBr solutions containing powdered enzyme. The enzyme may bind to the caffeoyl moiety of 5-CQA or CA to form an enzyme-substrate complex. It then catalyzes four different reactions corresponding to the reaction conditions.


Subject(s)
Chlorogenic Acid/chemistry , Coumaric Acids/chemistry , Esters/chemistry , Hydrolases/chemistry , Aspergillus/enzymology , Bromine , Caffeic Acids/chemistry , Caffeic Acids/metabolism , Chlorogenic Acid/metabolism , Coumaric Acids/chemical synthesis , Coumaric Acids/metabolism , Esterification , Esters/chemical synthesis , Esters/metabolism , Ethylene Dibromide/metabolism , Hydrogen-Ion Concentration , Hydrolases/metabolism , Phenylethyl Alcohol/analogs & derivatives , Phenylethyl Alcohol/chemistry , Phenylethyl Alcohol/metabolism
13.
Dentomaxillofac Radiol ; 33(6): 391-5, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15665233

ABSTRACT

OBJECTIVES: The purpose of this study was to evaluate the usefulness of the limited cone-beam X-ray CT (3DX) (Morita Co., Japan) in measuring the thickness of the roof of the glenoid fossa (RGF) of the temporomandibular joint (TMJ). MATERIALS AND METHODS: Twenty-one TMJs removed at autopsy from 21 cadavers were investigated macroscopically using dissection and 3DX imaging. A Digimatic Outside Micrometer and a 3DX-image tool were used to measure the minimum thickness of the RGF. Multiple measurements were made to identify the thinnest area. Once the thinnest areas had been identified, three linear measurements were made and the average value was used for statistical analysis. RESULTS: The average macroscopic examination measurement was 1.37 mm (range 0.55-3.6 mm) and the average 3DX image measurement was 1.22 mm (range: 0.51-3.0 mm). There was no significant difference between these two groups using the Mann-Whitney U-test (P < 0.05). The Spearman's correlation coefficient by rank between these two groups was r = 0.93(P < 0.001). CONCLUSION: These results suggest that bone thickness measurements of the RGF by 3DX imaging was effective.


Subject(s)
Imaging, Three-Dimensional/methods , Temporal Bone/diagnostic imaging , Temporomandibular Joint/diagnostic imaging , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Bone Density , Female , Humans , Male , Mandibular Condyle/diagnostic imaging , Middle Aged , Reproducibility of Results , Statistics, Nonparametric
14.
J Neurol Neurosurg Psychiatry ; 74(4): 419-22, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12640053

ABSTRACT

OBJECTIVE: The purpose of this study was to analyse changes in regional cerebral blood flow (rCBF) in Parkinson's disease (PD) without dementia. METHODS: Twenty eight non-demented patients with PD and 17 age matched normal subjects underwent single photon emission computed tomography with N-isopropyl-p-[(123)I]iodoamphetamine to measure rCBF. The statistical parametric mapping 96 programme was used for statistical analysis. RESULTS: The PD patients showed significantly reduced rCBF in the bilateral occipital and posterior parietal cortices (p<0.01, corrected for multiple comparison p<0.05), when compared with the control subjects. There was a strong positive correlation between the score of Raven's coloured progressive matrices (RCPM) and the rCBF in the right visual association area (p<0.01, corrected for multiple comparison p<0.05) among the PD patients. CONCLUSIONS: This study showed occipital and posterior parietal hypoperfusion in PD patients without dementia. Furthermore, it was demonstrated that occipital hypoperfusion is likely to underlie impairment of visual cognition according to the RCPM test, which is not related to motor impairment.


Subject(s)
Cerebrovascular Circulation/physiology , Cognition Disorders/etiology , Cognition Disorders/physiopathology , Dementia/complications , Dementia/physiopathology , Occipital Lobe/physiopathology , Parkinson Disease/complications , Parkinson Disease/physiopathology , Vision Disorders/etiology , Vision Disorders/physiopathology , Visual Cortex/physiopathology , Aged , Cognition Disorders/diagnostic imaging , Dementia/diagnostic imaging , Female , Humans , Male , Middle Aged , Neuropsychological Tests , Occipital Lobe/diagnostic imaging , Parkinson Disease/diagnostic imaging , Severity of Illness Index , Tomography, Emission-Computed, Single-Photon , Vision Disorders/diagnostic imaging , Visual Cortex/diagnostic imaging
15.
Endoscopy ; 35(4): 363-5, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12664397

ABSTRACT

Inflammatory myoglandular polyp is an uncommon benign colorectal polyp. We treated nine cases of histologically verified inflammatory myoglandular polyp. The polyps were identified as a pedunculated protrusion located in the distal part of the large intestine. On colonoscopy, eight polyps had a smooth, spherical, and hyperemic surface, accompanied by a patchy mucous exudate. Magnification endoscopy revealed a rugged surface composed of smooth nodules. These colonoscopic findings corresponded to hyperplastic glands with occasional cystic dilation and inflamed stroma with proliferation of smooth-muscle fibers. Inflammatory myoglandular polyp appears to be a distinctive clinical entity, with a unique appearance on colonoscopy.


Subject(s)
Colonic Polyps/surgery , Adult , Aged , Colonic Polyps/diagnosis , Colonic Polyps/pathology , Female , Humans , Male , Middle Aged , Rectal Diseases/diagnosis , Rectal Diseases/pathology , Rectal Diseases/surgery
16.
Radiat Prot Dosimetry ; 103(1): 47-55, 2003.
Article in English | MEDLINE | ID: mdl-12596989

ABSTRACT

A method for measuring entrance surface dose in intraoral radiography for nationwide survey for the determination of guidance levels was developed using a commercially available radiophotoluminescent dosemeter (RPLD) system. From the ratio of the readings of the RPLD detectors. with and without a 1 mm thick aluminium filter, half value layer (HVL) and the energy dependency correction factor were derived. HVL and exposure for intraoral radiography were obtained with uncertainties of +/- 0.11 mmAl (SD) and +/- 2.1% (CV), respectively. This has been achieved by calibration at various beam qualities used in intraoral radiography. The HVLs and outputs of intraoral radiography units were measured by means of the mailed RPLD holders and also by ionisation chambers in 19 dental schools in Japan. Results obtained from the two methods of measurement agreed well for both HVLs and outputs.


Subject(s)
Radiation Monitoring/instrumentation , Radiography, Dental , Radiometry/methods , Air , Air Ionization/radiation effects , Aluminum , Calibration , Dose-Response Relationship, Radiation , Humans , Japan , Luminescent Measurements , Polyethylene Terephthalates , Radiation Dosage , Scattering, Radiation , Schools, Dental , Water
17.
Radiat Prot Dosimetry ; 107(4): 247-52, 2003.
Article in English | MEDLINE | ID: mdl-14756181

ABSTRACT

It has been reported that exposure of patients and physicians to radiation from interventional radiological procedures cannot be disregarded. Direct measurement of patient exposure used to be difficult due to possible interference by the detector with the observation of X ray images. Recently, a dosemeter system consisting of small-sized glass chips and a reader which adopts pulsed UV laser stimulation has been developed. Owing to its small size, radiolucency and physical characteristics, direct monitoring of surface dose has become feasible. Dose measurement for patients and physicians during neurointervention was done using the photoluminescence glass dosemeter system. The dose-response of the dosemeter was almost linear over a broad dose range, but its energy dependency was rather high without a filter, the use of which is recommended by the manufacturer to compensate for energy dependency. Variation of sensitivity of about 20% was observed for effective energies of 45-60 keV which are used in neurointervention. In spite of this shortcoming, the photoluminescence glass dosemeter system was judged to be a convenient means for monitoring dose during neurointervention.


Subject(s)
Angiography/methods , Cerebrovascular Disorders/diagnostic imaging , Occupational Exposure/analysis , Radiation Protection/instrumentation , Radiometry/instrumentation , Angiography/instrumentation , Equipment Failure Analysis , Fluoroscopy/instrumentation , Fluoroscopy/methods , Glass , Humans , Patient Care Management/methods , Radiation Dosage , Radiology Department, Hospital , Reproducibility of Results , Sensitivity and Specificity
18.
Endoscopy ; 34(12): 956-8, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12471538

ABSTRACT

BACKGROUND AND STUDY AIMS: Brunner's gland hamartomas are uncommon duodenal submucosal tumors. We aim to describe their morphological characteristics, with particular attention to the endosonographic features. PATIENTS AND METHODS: We reviewed the radiological, endoscopic, endosonographic, and histological findings from six Brunner's gland hamartomas which were completely removed by endoscopic resection. RESULTS: The lesions appeared as broad-based, sessile, or pedunculated submucosal tumors, measuring 0.7 to 2 cm in maximal diameter. Three lesions contained tiny dimple-like depressions on the surface; in one lesion these were only recognized following the use of an endoscopic dye-spraying technique. All the lesions could be safely removed by endoscopic resection after endosonographic confirmation of the layer origin within the submucosa. The internal echo structure of the tumors appeared to be solid echogenic in two, simple cystic in two, and multicystic in the remaining two lesions. In three lesions with an indistinct boundary, some stromal proliferation and solid Brunner's glands were recognized in an area extending from the mucosa to the submucosa. These endosonographic features corresponded to histological findings comprising stromal proliferation and various degrees of solid and cystic glandular Brunner's glands. CONCLUSIONS: Brunner's gland hamartoma is characterized endosonographically by a heterogeneous solid and/or cystic mass within the submucosa.


Subject(s)
Brunner Glands/diagnostic imaging , Duodenal Diseases/diagnostic imaging , Duodenal Diseases/pathology , Endosonography , Hamartoma/diagnostic imaging , Hamartoma/pathology , Adult , Aged , Brunner Glands/pathology , Duodenal Diseases/surgery , Female , Hamartoma/surgery , Humans , Male , Middle Aged
19.
Endoscopy ; 34(12): 973-8, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12471541

ABSTRACT

BACKGROUND AND STUDY AIMS: Endoscopic resection is increasingly being used in the treatment of early gastric cancer. The aim of the present study was to investigate the accuracy of pretherapeutic staging techniques for assessing the appropriateness of endoscopic resection. PATIENTS AND METHODS: Both endoscopy and endosonography were carried out at our institution in the treatment of 234 early gastric cancers, with histological confirmation of malignancy following surgical resection (137 lesions) or endoscopic resection (97 lesions). The accuracy in detecting intramucosal cancer with each of the diagnostic procedures was assessed. RESULTS: The accuracy rates for detecting intramucosal cancer using endoscopy and endosonography were calculated as 84 % (197 of 234) and 78 % (182 of 234), respectively. The accuracy tended to be lower in lesions located in the upper third of the stomach, in those measuring 2 cm or more in diameter, and in those with an undifferentiated histology with ulcer fibrosis. However, there were no significant differences in the accuracy rates between endoscopy and endosonography. Precise staging was achieved by endoscopy alone in 103 of 109 differentiated adenocarcinomas without ulcer fibrosis, where the lesions measured less than 2 cm in diameter. CONCLUSIONS: Endoscopic resection is indicated in intramucosal gastric cancer lesions showing differentiated histology, no ulcer fibrosis and a diameter of less than 2 cm. EUS may additionally be used for further evaluation in these patients.


Subject(s)
Endosonography , Gastroscopy , Stomach Neoplasms/diagnostic imaging , Stomach Neoplasms/surgery , Female , Humans , Male , Middle Aged , Neoplasm Staging/methods , Stomach Neoplasms/pathology
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