Biomedical subjects

Rie Tanaka

Publications and source records attributed to Rie Tanaka.

At least 19 recordsLinked to original sources

PubMed2006

Meat, milk, saturated fatty acids, the Pro12Ala and C161T polymorphisms of the PPARgamma gene and colorectal cancer risk in Japanese.

The peroxisome proliferator-activated receptor gamma (PPARgamma) gene plays important roles in energy homeostasis. To examine interactions between consumption of foods and fatty acids and the Pro12Ala and C161T (His447His) polymorphisms for colorectal cancer, we performed two case-control studies in Japanese. In study 1, there were 128 colorectal cancer cases and 238 non-cancer controls, and in study 2 there were 257 cases and 771 (age- and sex-matched) non-cancer controls. Assessment of food and nutrients consumption in study 1 was via a nine-item questionnaire, while in study 2 assessment of consumption was according to a more detailed semiquantitative food frequency questionnaire. Consumption of foods and fatty acids was divided into low, moderate and high groups. The overall frequency of the Ala allele was <4%, and the frequencies of the Pro/Pro + C/C and Pro/Pro + (C/T + T/T) genotypes were 70-73% and 20-26%, respectively. Compared with subjects with low meat intake and the Pro/Pro + C/C genotype, those with high meat consumption and the same genotype had a stronger increased risk in study 1 [OR, 2.88; 95% CI, 1.14-7.30; P for trend = 0.02], but a positive association with processed meat consumption was greatest in those with the Pro/Pro + (C/T + T/T) genotype (P for trend = 0.05) in study 2. Likewise, high consumption of saturated fatty acids and milk appeared to confer marginal increased risk and stronger decreased risk, respectively, in those with the Pro/Pro and Pro/Pro + C/C genotypes (OR, 1.35 and 0.65; 95% CI, 0.93-1.96 and 0.43-1.00; P for trend = 0.10 and 0.06). Further large-scale studies are needed to determine colorectal cancer risk according to relationships between the PPARgamma gene polymorphisms and dietary intakes of meat, processed meat, milk and saturated fatty acids in Japanese with very low frequency of the Ala allele.

Adult↗

PubMed2006

Complete removal of HIV-1 RNA and proviral DNA from semen by the swim-up method: assisted reproduction technique using spermatozoa free from HIV-1.

BACKGROUND: Use of antiretroviral drugs has reduced the mortality rate for HIV infection and many HIV-discordant couples wish to have children. It is possible for an HIV-infected man to father children without risk of HIV transmission if HIV-free spermatozoa can be obtained from his semen. METHODS: An improved swim-up method was used to collect HIV-free spermatozoa from the semen of HIV-positive males. Diluted semen was layered over a Percoll solution with a continuous density gradient of 30-98%, and then centrifuged. The bottom layer was collected by cutting the end from the tube and the sperm suspension was collected using the swim-up method. Spermatozoa were tested by nested polymerase chain reaction (PCR) for HIV-1 RNA and DNA, with a detection limit of one copy. Spermatozoa were used for assisted reproduction in 43 couples. RESULTS: HIV-1 RNA and proviral DNA were not detected by nested-PCR assay in all 73 of the collected spermatozoa samples from 52 patients. The HIV-1-negative sperm was used for in vitro fertilization in 12 couples and for intracytoplasmic sperm injection in 31 couples. No detection of HIV-1 RNA or proviral DNA in the culture medium of the fertilized eggs was confirmed again before embryo transfer. Of the 43 female partners, 20 conceived and 27 babies were born. HIV antibodies, HIV RNA and proviral DNA were negative in all of the females and babies. CONCLUSIONS: HIV-negative spermatozoa could be obtained from semen of HIV-positive men. The method involves no risk of HIV transmission to female partners and their children.

Adult↗

PubMed2006

Computerized methods for determining respiratory phase on dynamic chest radiographs obtained by a dynamic flat-panel detector (FPD) system.

Chest radiography using a dynamic flat-panel detector with a large field of view can provide sequential chest radiographs during respiration. These images provide information regarding respiratory kinetics, which is effective for diagnosis of pulmonary diseases. For valid analysis of respiratory kinetics in diagnosis of pulmonary diseases, it is crucial to determine the association between the kinetics and respiratory phase. We developed four methods to determine the respiratory phase based on image information associated with respiration and compared the results in dynamic chest radiographs of 37 subjects. Here, the properties of each method and future tasks are discussed. The method based on the change in size of the lung gave the most stable results, and that based on the change in distance from the lung apex to the diaphragm was the most promising method for determining the respiratory phase.

Humans↗

PubMed2006

Evaluation of pulmonary function using breathing chest radiography with a dynamic flat panel detector: primary results in pulmonary diseases.

OBJECTIVES: Dynamic flat panel detectors (FPD) permit acquisition of distortion-free radiographs with a large field of view and high image quality. The present study was performed to evaluate pulmonary function using breathing chest radiography with a dynamic FPD. We report primary results of a clinical study and computer algorithm for quantifying and visualizing relative local pulmonary airflow. MATERIALS AND METHODS: Dynamic chest radiographs of 18 subjects (1 emphysema, 2 asthma, 4 interstitial pneumonia, 1 pulmonary nodule, and 10 normal controls) were obtained during respiration using an FPD system. We measured respiratory changes in distance from the lung apex to the diaphragm (DLD) and pixel values in each lung area. Subsequently, the interframe differences (D-frame) and difference values between maximum inspiratory and expiratory phases (D-max) were calculated. D-max in each lung represents relative vital capacity (VC) and regional D-frames represent pulmonary airflow in each local area. D-frames were superimposed on dynamic chest radiographs in the form of color display (fusion images). The results obtained using our methods were compared with findings on computed tomography (CT) images and pulmonary functional test (PFT), which were examined before inclusion in the study. RESULTS: In normal subjects, the D-frames were distributed symmetrically in both lungs throughout all respiratory phases. However, subjects with pulmonary diseases showed D-frame distribution patterns that differed from the normal pattern. In subjects with air trapping, there were some areas with D-frames near zero indicated as colorless areas on fusion images. These areas also corresponded to the areas showing air trapping on computed tomography images. In asthma, obstructive abnormality was indicated by areas continuously showing D-frame near zero in the upper lung. Patients with interstitial pneumonia commonly showed fusion images with an uneven color distribution accompanied by increased D-frames in the area identified as normal on computed tomography images. Furthermore, measurement of DLD was very effective for evaluating diaphragmatic kinetics. CONCLUSIONS: This is a rapid and simple method for evaluation of respiratory kinetics for pulmonary diseases, which can reveal abnormalities in diaphragmatic kinetics and regional lung ventilation. Furthermore, quantification and visualization of respiratory kinetics is useful as an aid in interpreting dynamic chest radiographs.

Adult↗

PubMed2006

Interfacial behavior of fatty-acylated sericin prepared by lipase-catalyzed solid-phase synthesis.

Fatty-acylated sericin {1:0.7 molar ratio of sericin (Mr 18,700) to oleic acid} was prepared by lipase-catalyzed solid-phase synthesis in n-hexane containing oleic acid to endow sericin with interfacial properties. Acylation with oleic acid was confirmed by 1H-NMR. The fatty-acylated sericin exhibited superior emulsifying activity index and emulsion stability in the presence of 0-0.5 M NaCl, in a temperature range of 30-80 degrees C and pH range of 2-7, as compared with the control sericin. The fatty-acylated sericin (1:0.4 molar ratio) prepared by using low-molecular-weight sericin (Mr 5,000) also exhibited superior emulsifying properties. The affinity of the fatty-acylated sericin to a hydrophobic surface as evaluated by a biomolecular interaction analyzer was about twice as much as that of the control sericin. The fatty-acylated sericin showed retarded water vaporization, similar to the control sericin, indicating good retention of moistness, and was adsorbed four times as much to defatted wool with little desorption as compared with the control sericin.

Acylation↗

PubMed2005

Development of a semi-automated superimposing image verification system using a template matching algorithm in radiotherapy.

To analyze shifts in the isocenter of images, we developed a semi-automated superimposing image-verification system that is capable of automatically quantifying shifts in the isocenter through image analysis with a personal computer (PC). The accuracy and usefulness of this software were examined through a comparison of nine portal images with a simulation image and by comparing nine portal images with a DRR image, using a human pelvic phantom. The difference between the known magnitude of shift and the magnitude of shift detected with this method was analyzed as detection error. When the portal images were compared with the simulation image, the 95% confidence interval (95% CI) of detection errors (mean+/-SD) was 0.57+/-0.36 mm (95% CI: 0.49-0.65 mm). When the portal images were compared with the DRR image, the respective figures were 0.68+/-0.38 mm (95% CI: 0.59-0.77 mm). No significant difference was noted between these two categories of comparison (N.S). The absolute detection error (mean+/-SD) in all directions was 0.34+/-0.34 mm for the comparison of portal images with the simulation image and 0.41+/-0.36 mm for the comparison of portal images with the DRR image. This system seems to be appropriate for verification of the treatment field by improving the accuracy of radiotherapy as a method of computer-assisted landmark recognition during image comparison.

Algorithms↗

PubMed2005

Development of computerized patient setup verification and correction system in radiotherapy.

Visual comparison of a reference image with a verification image is commonly used for setup verification in external beam radiation therapy. However, it sometimes lacks reproducibility and provides insufficient quantitative evidence. The present study was performed to develop computerized methods for determining landmarks to verify a portal image with digital reconstruction radiograph (DRR), and to investigate the clinical effectiveness of our method. Our computer algorithm consisted of three main procedures--preprocessing, determination of landmarks, and verification--none of which required manual operation. Finally, our system indicated the distance for setup correction. We evaluated the accuracy of our system using pelvic phantom images, and the maximum magnitude of error was shown to be 1.12 (n=9). The results indicated that the error range of our system was sufficiently small to examine patient positioning error, which should be less than 5 mm, as described in AAPM report TG40. Our system will aid operators in positioning patients accurately for external radiation therapy.

Algorithms↗

PubMed2005

Synthesis of digalactosyl diacylglycerols and their structure-inhibitory activity on human lanosterol synthase.

Digalactosyl and monogalactocyl diacylglycerols (DGDG and MGDG), which were identified as anti-hyperlipemia active components in Colocasia esculenta (Taro), were synthesized. The inhibitory activity of DGDG, MGDG and related compounds on human lanosterol synthase was evaluated as anti-hyperlipemic activity. DGDG with two myristoyl groups at both sn-1 and sn-2 positions and with an oleoyl group at the sn-1 position showed the most potent activity.

Carbohydrate Sequence↗

PubMed2005

Inhibition of human lanosterol synthase by the constituents of Colocasia esculenta (taro).

Ethanol extracts of lyophilized vegetables were tested for inhibition of human lanosterol synthase (hOSC) in order to find the compounds to suppress cholesterol biosynthesis. Of 130 samples tested, twelve samples showed significant inhibition. Among them, Colocasia esculenta (taro) showed the highest inhibition (55% inhibition at 300 microg/ml). Examination of activity variation among eight taro cultivars indicated that "Aichi-wase" and "Yatsugashira" had the most potent activity for hOSC inhibition. In order to identify the active constituent of taro, ethanol extracts of "Aichi-wase" were partitioned with hexane and aqueous methanol, and fractionated by silica gel column chromatography. Inhibitory activity was concentrated in two major active fractions. Further purification of these fractions by preparative HPLC gave three monogalactosyldiacylglycerols and five digalactosyldiacylglycerols as active compounds that showed 28 to 67% inhibitory activities at the concentration 300 microg/ml.

Colocasia↗

PubMed2004

Breathing chest radiography using a dynamic flat-panel detector combined with computer analysis.

Kinetic information is crucial when evaluating certain pulmonary diseases. When a dynamic flat-panel detector (FPD) can be used for a chest examination, kinetic information can be obtained simply and cost-effectively. The purpose of this study was to develop methods for analyzing respiratory kinetics, such as movement of the diaphragm and lung structures, and the respiratory changes in x-ray translucency in local lung fields. Postero-anterior dynamic chest radiographs during respiration were obtained with a modified FPD, which provided dynamic chest radiographs at a rate of 3 frames/s. Image registration for correction of physical motion was followed by measurement of the distance from the lung apex to the diaphragm. Next, we used a cross-correlation technique to measure the vectors of respiratory movement in specific lung areas. Finally, the average pixel value for a given local area was calculated by tracing the same local area in the lung field. This method of analysis was used for six healthy volunteers and one emphysema patient. The results reported here represent the initial stage in the development of a method that may constitute a new method for diagnosing certain pulmonary diseases, such as chronic obstructive pulmonary disease, fibroid lung, and pneumonia. A clinical evaluation of our method is now in progress.

Humans↗

PubMed2004

[Study of optimal imaging parameters for digitally reconstructed radiographs (DRR) in radiotherapy treatment planning using single-slice helical CT].

In recent years, by making digitally reconstructed radiographs (DRR) from helical CT images in the position check of an irradiation field, the verification performed by DRR, lineacgraphy (LG), or an electronic portal imaging device (EPID) has become possible. We examined the optimal parameters of single-slice helical scanning in DRR image construction and the usefulness of DRR replaced with the simulation film. We performed a section sensitivity profile at the Z-axis (SSPz) as evaluation of a physical characteristic of helical CT equipment and the form of image of DRR, fixed quantity evaluation of imaging distortion, and visual verification of images. It was determined that DRR was influenced by the partial volume effect depending on slice thickness and pitch, such that this influence occurred when slice thickness and pitch were large. Between a simulation film and DRR reconstructed using imaging parameters with a slice thickness of 3 mm, pitch of 1.0, and reconstruction slice thickness of 3 mm, coincidence was not complete. However, the distortion of DRR was small and the difference was not statistically; thus it was considered to be useful. In conclusion, we consider that DRR reconstructed using the parameters of single-slice helical scanning is useful for clinical evaluation in radiotherapy planning.

Humans↗

PubMed2003

Two lysosomal membrane proteins, LGP85 and LGP107, are delivered to late endosomes/lysosomes through different intracellular routes after exiting from the trans-Golgi network.

Lysosomal membrane proteins are delivered from their synthesis site, the endoplasmic reticulum (ER) to late endosomes/lysosomes through the Golgi complex. It has been proposed that after leaving the Golgi they are transported either directly or indirectly (via the cell surface) to late endosomes/lysosomes. In the present study, we examined the transport routes taken by two structurally different lysosomal membrane proteins, LGP85 and LGP107, in rat 3Y1-B cells. Here we show that newly synthesized LGP85 and LGP107 are delivered to late endosomes/lysosomes via a direct route without passing through the cell surface. Interestingly, although LGP107 is delivered from the Golgi to early endosomes containing internalized horseradish peroxidase-conjugated transferrin (HRP-Tfn) en route to lysosomes, LGP85 does not pass through the HRP-Tfn-positive early endosomes. These results suggest, therefore, that LGP85 and LGP107 are sorted into distinct transport vesicles at the post-Golgi, presumably the trans-Golgi network (TGN), after which LGP85 is delivered directly to late endosomes/lysosomes, but significant fractions of LGP107 are targeted to early endosomes before transport to late endosomes/lysosomes. This study provides the first evidence that after exiting from the Golgi, LGP85 and LGP107 are targeted to late endosomes/lysosomes via a different pathway.

Animals↗

PubMed2003

Cloning and characterization of two novel crystal protein genes from a Bacillus thuringiensis serovar dakota strain.

Two genes encoding the 32- and 40-kDa polypeptides of Bacillus thuringiensis strain 90-F-45-14 crystals were cloned, expressed in an acrystalliferous B. thuringiensis strain, and sequenced. The polypeptides had deduced molecular weights of 30,319 and 33,885, respectively. The amino acid sequence of the 32-kDa protein was 37.7% identical to the known sequence of a non-insecticidal parasporal protein in B. thuringiensis serovar thompsoni crystals. The sequence of the cloned 40-kDa protein was 37.0% and 22.3% identical to that of the existing Cry protein classes, Cry15Aa1 and Cry23Aa1, respectively. Thus, this protein constitutes a novel protein class, Cry33Aa1. The open reading frames of the two genes were located on the predominant plasmid of 17,629 bp (=11,752 MDa) in the same orientation, and they were separated by the sequence of 32 nucleotides. The two proteins are likely produced simultaneously from a single transcript to form spherical crystals.

Amino Acid Sequence↗

PubMed2003

[Development of breathing chest radiography: study of exposure timing].

The flat-panel detector (FPD) has been introduced into clinical practice. A modified FPD, which has the ability to obtain dynamic chest radiographs, was introduced into our hospital, and clinical testing is ongoing. Both the inspiratory and expiratory phases have to be included in dynamic chest radiographs. The purpose of this study was to investigate the most appropriate chest radiography signal for observation of the respiratory process. We prepared ten protocol patterns that differed in terms of respiratory phase at X-ray exposure, exposure duration, and signal multiplicity. We also performed preliminary experiments and administered several questionnaires to ten volunteers. The volunteers breathed according to vocal and visual signals, and their respiratory waves were recorded by spirometer. The most appropriate protocol was similar to the method used for conventional chest radiography.

Adult↗

PubMed2003

[Screening chest X-ray examination with kinetic analysis using flat-panel detector].

We are developing dynamic screening radiography to provide kinetic information for lung respiratory examination using a flat-panel-detector (FPD) system. We modified the FPD system (CANON CXDI-22) to take sequential images for a short period of time (10 seconds, 3 frames/sec). Sequential chest radiographs from full inspiration to expiration were taken and analyzed for diaphragm movement and density changes in local lung areas to objectively detect respiratory anomalies. Our methods derived some respiratory functions such as regional air passage and lung structure movement, and suggested that the degree of chronic obstructive pulmonary disease and interstitial pneumonia could be evaluated quantitatively.

Aged↗

PubMed2002

A new noninvasive measurement system for wave intensity: evaluation of carotid arterial wave intensity and reproducibility.

Wave intensity (WI) is a new hemodynamic index that provides information about the dynamic behavior of the heart and the vascular system and their interaction. Carotid arterial wave intensity in normal subjects has two positive peaks. The first peak, W(1), occurs during early systole, the magnitude of which increases with increases in cardiac contractility. The second peak, W(2), which occurs towards the end of ejection, is related to the ability of the left ventricle to actively stop aortic blood flow. Between the two positive peaks, a negative area, NA, is often observed, which signifies reflections from the cerebral circulation. The time interval between the R-wave of ECG and the first peak (R - W(1)) corresponds to the pre-ejection period, and that between the first and second peaks (W(1) - W(2)) corresponds to ejection time. We developed a new ultrasonic on-line system for obtaining WI and arterial stiffness (beta). The purpose of this study was (1) to report normal values of various indices derived from WI and beta measured with this system, and (2) to evaluate the intraobserver and interobserver reproducibility of the measurements. The measurement system is composed of a computer, a WI unit, and an ultrasonic machine. The WI unit gives the instantaneous change in diameter of the artery and the instantaneous mean blood velocity through the sampling gate. Using these parameters and blood pressure measured with a cuff-type manometer, the computer gives WI and beta. We applied this method to the carotid artery in 135 normal subjects. The mean values of W(1), W(2), NA, R - W(1), and W(1) - W(2) were 8 940 +/- 3 790 mmHg m/s(3), 1 840 +/- 880 mmHg m/s(3), 27 +/- 13 mmHg m/s(2), 104 +/- 14 ms, and 270 +/- 19 ms, respectively. These values did not show a significant correlation with age. The mean value of beta was 10.4 +/- 4.8 and the values significantly correlated with age (men: r = 0.66, P < 0.0001; women: r= 0.81, P < 0.0001). The reproducibility was evaluated by intraobserver intrasession (IA), intraobserver intersession (IE), and interobserver intrasession variability (IO). The reproducibility of R - W(1) and W(1) - W(2) was high: the mean coefficient of variation (mCV) of IA was less than 3%; 95% confidence limits from the mean values (CL) were less than 8% for IE and less than 4% for IO. The reproducibility of W(1) and beta was good: mCV for IA was less than 10%; CL for IE and IO were less than 17%. W(2) and NA showed a higher variability than other indices: mCV for IA was less than 13%, and CL for IE and IO were less than 36%. However, two sessions by the same observer and two sessions by different observers were not biased. Wave intensity measurements with this system are clinically acceptable.

Adult↗

PubMed2002

[Study on the determination of pesticide residues in crops by ion-trap GC/MS/MS].

Ion-trap GC/MS/MS was evaluated for the multi-residue determination of pesticides in agricultural products. Matrices were extracted from samples (spinach, carrot, onion and brown rice) with acetone and submitted to gel permeation chromatography, followed by a clean-up step through a graphite carbon cartridge. Thirty-five pesticides were added to either matrix, and analyzed by GC/MS/MS. Detection limits of pesticides by GC/MS/MS was almost the same as those by GC/MS (SIM). Coefficients of variation of peak area in 5 measurements of each pesticide at 0.1 microgram/mL or 0.05 microgram/mL with or without matrices were mostly acceptable, though those of 20 pesticides out of 35 were higher than 10% at a concentration of 0.02 microgram/mL. It was indicated that matrix artifacts, which interfere with GC/MS-Scan analysis, could be eliminated in some cases by using GC/MS/MS.

Crops, Agricultural↗

PubMed2002

[New screening chest radiography with computer analysis of pulmonary marking movement and change in regional density].

Respiratory function data are useful for the evaluation of lung disease. To develop a new method of computer analysis for screening chest radiography that would provide respiratory kinetics automatically, we quantified and analyzed the movement of pulmonary markings and the changes in lung density during respiration. In this study, we obtained fluoroscopic chest images of a healthy volunteer during respiration using an image intensifier (I. I.) fluoroscopy system. We analyzed the vector of the movement of pulmonary markings and measured the regional mean density of sequential chest images during respiration. The movement of pulmonary markings in the upper lung field was less than that in the lower lung field. Variation in the phase density curve of the upper lung field was less than that of the lower lung field. Our results indicate that changes in density were regular and were synchronized with respiration. This computerized method may aid radiologists in the evaluation of lung diseases such as chronic obstructive pulmonary disease (COPD) , where abnormal respiratory change in density occurs as a result of air trapping.

Humans↗