134 research outputs found
Hepatitis B virus genotype assignment using restriction fragment length polymorphism patterns
AbstractHepatitis B virus (HBV) is classified into genotypes A–F, which is important for clinical and etiological investigations. To establish a simple genotyping method, 68 full-genomic sequences and 106 S gene sequences were analyzed by the molecular evolutionary method. HBV genotyping with the S gene sequence is consistent with genetic analysis using the full-genomic sequence. After alignment of the S sequences, genotype specific regions are identified and digested by the restriction enzymes, HphI, NciI, AlwI, EarI, and NlaIV. This HBV genotyping system using restriction fragment length polymorphism (RFLP) was confirmed to be correct when the PCR products of the S gene in 23 isolates collected from various countries were digested with this method. A restriction site for EarI in genotype B was absent in spite of its presence in all the other genotypes and genotype C has no restriction site for AlwI. Only genotype E is digested with NciI, while only genotype F has a restriction site for HphI. Genotype A can be distinguished by a single restriction enzyme site for NlaIV, while genotype D digestion with this enzyme results in two products that migrates at 265 and 186 bp. This simple and accurate HBV genotyping system using RFLP is considered to be useful for research on HBV
A case-control study for differences among hepatitis B virus infections of genotypes A (subtypes Aa and Ae) and D
There are two subtypes of hepatitis B virus genotype A (HBV/A) and they are provisionally designated Aa (a standing for Africa/Asia) and Ae (e for Europe). In a case-control study, 78 HBV/Aa, 78HBV/Ae, and 78HBV/D carriers from several countries were compared. The prevalence of HBe antigen (HBeAg) in serum was significantly lower in carriers of HBV/Aa than in carriers of HBV/Ae (31% vs. 49%; P = .033), with a difference more obvious in the carriers aged 30 years or younger (34% vs. 67%; P = .029). HBV DNA levels in the carriers of HBV/Aa (median, 3.46 log copies/mL; 95% CI, 2.93-3.95) were significantly lower than those of carriers of HBV/Ae (6.09 log copies/mL; 95% CI, 4.24-7.64) or of carriers of HBV/D (5.48 log copies/mL; 95% CI, 4.06-7.02), regardless of the HBeAg status (P < .001). The most specific and frequent substitutions in 54 HBV/Aa isolates were double substitutions for T1809 (100%) and T1812 (96%) immediately upstream of the precore initiation codon, which would interfere with the translation of HBeAg in HBV/Aa infections. They were not detected in 57 HBV/Ae or 61 HBV/D isolates examined. The double mutation in the core promoter (T1762/A1764) was more frequent in both HBV/Aa (50%) and HBV/Ae (44%) than in HBV/D isolates (25%; P < .01), whereas the precore mutation (A1896) occurred in HBV/D isolates only (48%; P < .0001). In conclusion, the clearance of HBeAg from serum may occur by different mechanisms in HBV/Aa, HBV/Ae, and HBV/D infections, which may influence clinical manifestations in the Western countries where both genotypes A and D are prevalent
ニホン ニ オケル セッショク ショウガイ ベイコク ト ノ ヒカク
近年、日本においてメタボリックシンドロームの患者数は増加する一方で、若い女性のやせの増加がうかがえる。日本における摂食障害の発症頻度は1990年代後半から急激に増加し欧米の国々と肩を並べてきている。しかし、欧米のように、日本ではここ10年間のきちんとした全国的な疫学調査がなされていない。また、日本では管理栄養士が介入した摂食障害の栄養指導はあまり行われてないのが現状である。これまでに米国の摂食障害の状況や摂食障害治療における米国の管理栄養士の役割と日本の現状を比較した論文は見当たらない。したがって、アメリカ合衆国と比較しながら、日本の摂食障害の現状をまとめた。その結果、管理栄養士が摂食障害治療チームに加わり栄養療法を行えるように、正確な実態を把握するための全国的な調査の必要性および摂食障害治療における栄養療法の重要性を示し、管理栄養士の役割を見出した。Although the number of patients with metabolic syndrome has been increasing recently, young females are still more likely to become thin. The incidence rate of eating disorders has been increasing rapidly since the late 1990\u27s and growing closer to that of Western countries. In contrast to the Western countries we looked at in our study, there has been no national epidemiological survey in the past 10 years in Japan. Additionally, it is still not common that registered dietitians join in treatment of eating disorders and provide nutrition therapy in Japan. Thus, this paper gave the outline of eating disorders in Japan by summarizing and comparing with the situation in the United States. This study revealed the importance of large national epidemiological surveys, medical nutrition therapy, and the role of registered dietitians in order to encourage registered dietitians to provide nutrition therapy by joining the teams treating eating disorders
A New Serum Biomarker Set to Detect Mild Cognitive Impairment and Alzheimer’s Disease by Peptidome Technology
Background:
Because dementia is an emerging problem in the world, biochemical markers of cerebrospinal fluid (CSF) and radio-isotopic analyses are helpful for diagnosing Alzheimer’s disease (AD). Although blood sample is more feasible and plausible than CSF or radiological biomarkers for screening potential AD, measurements of serum amyloid- β (Aβ), plasma tau, and serum antibodies for Aβ1 - 42 are not yet well established.
Objective:
We aimed to identify a new serum biomarker to detect mild cognitive impairment (MCI) and AD in comparison to cognitively healthy control by a new peptidome technology.
Methods:
With only 1.5μl of serum, we examined a new target plate “BLOTCHIP®” plus a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS) to discriminate control (n = 100), MCI (n = 60), and AD (n = 99). In some subjects, cognitive Mini-Mental State Examination (MMSE) were compared to positron emission tomography (PET) with Pittsburgh compound B (PiB) and the serum probability of dementia (SPD). The mother proteins of candidate serum peptides were examined in autopsied AD brains.
Results:
Apart from Aβ or tau, the present study discovered a new diagnostic 4-peptides-set biomarker for discriminating control, MCI, and AD with 87% of sensitivity and 65% of specificity between control and AD (***p
Conclusion:
The present serum biomarker set provides a new, rapid, non-invasive, highly quantitative and low-cost clinical application for dementia screening, and also suggests an alternative pathomechanism of AD for neuroinflammation and neurovascular unit damage
Bremsstrahlung X-ray Spectra for Enhanced K-edge Angiography
Energy-selective enhanced K-edge angiography utilizing a conventional x-ray generator is described. The x-ray generator is SOFRON NST-1005, and the maximum tube voltage and current are 100 kV and 5 mA, respectively. In the present research, the tube voltage ranged from 45 to 65kV, and the tube current was regulated to optimum values. The exposure time is controlled in order to obtain optimum x-ray intensity. At a charging voltage of 60 kV, the x-ray intensity rate obtained using an aluminum and a barium sulfate filters were 58.4 and 51.6 μGy/s at 0.7m per pulse, respectively, and the dimensions of the focal spot were approximately 1×1 mm. Angiography was performed using both the aluminum and the barium sulfate filters with a charging voltage of 60 kV
Measurement of Cerium X-ray Spectra Using a Cerium Oxide Powder Filter and Enhanced K-edge Angiography
The cerium-target x-ray tube is useful in order to perform cone-beam K-edge angiography because K-series characteristic x-rays from the cerium target are absorbed effectively by iodine-based contrast media. The x-ray generator consists of a main controller and a unit with a high-voltage circuit and a fixed anode x-ray tube. The tube is a glass-enclosed diode with a cerium target and a 0.5-mm-thick beryllium window. The maximum tube voltage and current were 70kV and 0.40mA, respectively, and the focal-spot sizes were approximately 1×1mm. Cerium K-series characteristic x-rays were left using a cerium oxide powder filter, and the x-ray intensity was 14.3μGy/s at 1.0m from the source with a tube voltage of 60kV, a current of 0.40mA, and an exposure time of 1.0s. Angiography was performed with a computed radiography system using iodine-based microspheres 15μm in diameter. In angiography of non-living animals, we observed fine blood vessels of approximately 100μm with high contrasts
X-ray Spectra from a Characteristic X-ray Generator with a Molybdenum Tube
This generator consists of the following components: a constant high-voltage power supply, a filament power supply, a turbomolecular pump, and an x-ray tube. The x-ray tube is a demountable diode which is connected to the turbomolecular pump and consists of the following major devices: a molybdenum rod target, a tungsten hairpin cathode (filament), a focusing electrode, a polyethylene terephthalate x-ray window 0.25mm in thickness, and a stainless-steel tube body. In the x-ray tube, the positive high voltage is applied to the anode (target) electrode, and the cathode is connected to the tube body (ground potential). In this experiment, the tube voltage applied was from 22 to 36kV, and the tube current was regulated to within 100μA by the filament temperature. The exposure time is controlled in order to obtain optimum x-ray intensity. The electron beams from the cathode are converged to the target by the focusing electrode, and x-rays are produced through the focusing electrode. Using a lithium fluoride curved crystal, clean K-series characteristic x-rays were observed without using a filter. However, bremsstrahlung x-rays were observed using a cadmium telluride detector
Angular dependence of x-ray spectra from a demountable x-ray tube with a copper target
The x-ray generator consists of the following components : a constant high-voltage power supply, a filament power supply, a turbomolecular pump, and an x-ray tube. The x-ray tube is a demountable diode which is connected to the turbomolecular pump and consists of the following major devices : a tungsten hairpin cathode (filament), a focusing electrode, a polyethylene terephthalate x-ray window 0.25mm in thickness, a stainless-steel tube body, and a rod target. In the x-ray tube, the positive high voltage is applied to the anode (target) electrode, and the cathode is connected to the tube body (ground potential). In this experiment, the tube voltage applied was from 12 to 18kV, and the tube current was regulated to within 0.10mA by the filament temperature. The electron beams from the cathode are converged to the target by the focusing electrode, and x-rays are produced from the target plane. The x-ray spectra were measured from two directions with angles between the electron trajectory and the x-ray beam axis of 180° and 90°. As compared with the x-ray spectra with an angle of 90°, the bremsstrahlung x-ray intensity decreased slightly with an angle of 180° (opposite direction to that of electron trajectory)
K-edge digital angiography using a flat panel detector with a pixel size of 50μm
The 100-μm-focus x-ray generator consists of a main controller for regulating the tube voltage and current and a tube unit with a high-voltage circuit and a fixed anode x-ray tube. The maximum tube voltage, current, and electric power were 105kV, 0.5mA, and 50W, respectively. Using a 3-mm-thick aluminum filter, the x-ray intensity was 26.0μGy/s at 1.0m from the source with a tube voltage of 60kV and a current of 0.50 mA. Because the peak photon energy was approximately 35keV using the filter with a tube voltage of 60kV, the bremsstrahlung x-rays were absorbed effectively by iodine-based contrast media with an iodine K-edge of 33.2keV. Enhanced angiography was achieved with a flat panel detector with a pixel size of 50μm using iodine-based microspheres 15μm in diameter. In angiography of non-living animals, we observed fine blood vessels of approximately 100gm with high contrasts
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