Application of ergothioneine-rich extract from an edible mushroom Flammulina velutipes for melanosis prevention in shrimp,Penaeus monodon and Litopenaeus vannamei

This report investigated the melanosis-inhibiting properties of crude water soluble extract from the base and fruiting body waste of an edible mushroom (Flammulina velutipes) containing 9.13 ± 2.03 mg/mL 2-thiol-l-histidine-betaine (ergothioneine, ESH). Immersion of live full-grown black tiger shrimp (Penaeus monodon) and Pacific white shrimp (Litopenaeus vannamei) in a 0.5% w/v solution of mushroom extract for 1 h significantly decreased polyphenoloxidase (PPO) activity in shrimp hemolymph and expression of the prophenoloxidase (proPO) gene in hemocytes. Consequently, the development of melanosis in the treated shrimp during ice storage was prevented. Treatment with a 0.05% w/v solution of sodium sulfite and 4-hexyl-1,3-benzenediol had a similar effect. Enzyme assays showed that ESH is a non-competitive inhibitor. It is proposed that ESH possibly interacts directly with Cu²⁺ at the putative binding sites of PPO and proPO, based on copper-chelating activity analyses, thus preventing melanosis in the shrimp. This study indicated that application of ESH-rich F. velutipes mushroom extract from trimming waste is an effective natural alternative to synthetic melanosis-inhibiting agents to prevent postmortem melanosis in shrimp.     

1/f noise behavior in semiconductor laser degradation

It is experimentally demonstrated that the increase in residual spectral linewidth during device degradation is due to an increase in 1/f noise in a multiple quantum-well (MQW) distributed-feedback (DFB) laser. The origin of 1/f noise and its influence on device characteristics is discussed and clarified by observing the degradation behavior of the spectral linewidth     

A highly repetitive sequence isolated from genomic DNA of the medaka (Oryzias latipes)

In order to investigate the relationship between various temporomandibular joint (TMJ) pain levels and the detection of high signal intensity (joint effusion) on T2 weighted magnetic resonance imaging (MRI), 19 consecutive patients who complained of unilateral painful TMJ hypomobility (closed locking) were involved in this study. All patients were clinically examined in a routine manner, and all patients rated their pain levels by a visual analogue scale and eight pain questionnaire prior MRI study. T1 and T2 weighted MRI was taken in sagittal section at unilateral affected joint side. The presence or absence of a high signal intensity spot within the TMJ compartment were judged by three examiners. The high signal intensity was detected in 10 joints, but not in 9 joints. In between these two groups, the pain ratio was calculated and compared. The data showed that there was no significant statistical correlation between pain levels and the presence of high signals. This study disclosed that the MRI detection of high signal intensity in the closed locking TMJ did not directly relate to the presence of TMJ pain nor the increased pain level. These indicate the need of further larger studies.     

Electrolytic reduction of U(VI) to U(IV) in acidic chloride and acidic sulfate solutions

In order to examine the applicability of the electrolytic reduction process of U(VI) (originally developed for the chloride system by PNC) to the sulfate solution system, a fundamental study was made. In this study, the concentrations of various chemical species in the catholytes were calculated at 298 K at various percentages of uranium reduction, taking the chloro-complex and sulfato-complex formation reactions of uranium into consideration. The polarization characteristics of the electrolytic reduction of uranyl chloride and uranyl sulfate were determined, using titanium and platinum cathodes, respectively, at 303 ± 1 K. In conjunction with this process, the electrical conductivity of the catholyte, the electrical resistivity of the cation exchange membrane, and the diffusion coefficient of uranyl sulfate were also determined.     

Optimized offset to eliminate first-order mode excitation at thejunction of straight and curved multimode waveguides

Applications to equip semiconductor phased-array wavelength demultiplexers with nonbirefringent waveguides are increasing. In several applications, the waveguides are multimodal and elimination of first-order mode excitation is required for their design. The optimized offset for eliminating the first-order mode excitation at the junction of straight and curved waveguides with a two-dimensional (2-D) structure is analyzed theoretically. We assume that the waveguide has a laterally symmetric index profile. By the perturbation method, the offset is obtained to the first order in the inverse of the bending radius. The offset is simply expressed by the effective refractive indices of the straight waveguide     

Electrochemical DNA methylation detection for enzymatically digested CpG oligonucleotides

We describe the electrochemical detection of DNA methylation through the direct oxidation of both 5-methylcytosine (mC) and cytosine (C) in 5'-CG-3' sequence (CpG) oligonucleotides using a sputtered nanocarbon film electrode after digesting a longer CpG oligonucleotide with endonuclease P1. Direct electrochemistry of the longer CpG oligonucleotides was insufficient for obtaining the oxidation currents of these bases because the CG rich sequence inhibited the direct oxidation of each base in the longer CpG oligonucleotides, owing to the conformational structure and its very low diffusion coefficient. To detect C methylation with better quantitativity and sensitivity in the relatively long CpG oligonucleotides, we successfully used an endonuclease P1 to digest the target CpG oligonucleotide and yield an identical mononucleotide 2'-deoxyribonucleoside 5'-monophosphate (5'-dNMP). Compared with results obtained without P1 treatment, we achieved 4.4 times higher sensitivity and a wider concentration range for mC detection with a resolution capable of detecting a subtle methylated cytosine difference in the CpG oligonucleotides (60mer).     

Cerebral glucose metabolism in patients with frontotemporal dementia

Frontotemporal dementia (FTD) is a dementia syndrome characterized by peculiar behavioral changes arising from frontotemporal involvement and distinct from Alzheimer's disease (AD). The purpose of this study was to elucidate the specific patterns in cerebral glucose metabolism in patients with FTD and to compare them with the patterns in patients with AD and normal elderly subjects using fluorodeoxyglucose (FDG) and PET. METHODS: Twenty-one patients with a clinical diagnosis of FTD [mean age 67.0 +/- 7.0 yr, Mini Mental State Examination (MMSE) score 18.7 +/- 5.7], 21 age-, sex- and dementia-severity-matched patients with probable AD (mean age 66.9 +/- 7.1 yr, MMSE score 20.2 +/- 5.5) and 21 age- and sex-matched normal control subjects (mean age 66.8 +/- 5.7 yr) were studied. The cerebral metabolic rate for glucose (CMRglc) was measured with FDG and PET. Absolute measures of regional CMRglc were compared among the three groups. One-way ANOVA and the posthoc Tukey HSD test were used for statistical analyses. RESULTS: In the FTD group, CMRglc was preserved only in the left cerebellum, right sensorimotor area and occipital lobes. The CMRglc was significantly lower in the FTD group as opposed to the AD group in the hippocampi, orbital gyri, anterior temporal lobes, anterior cingulate gyri, basal ganglia, thalami, middle and superior frontal gyri and left inferior frontal gyrus. CONCLUSION: Although metabolic abnormality in FTD is predominant in the frontal and anterior temporal lobes and the subcortical structures, it is more widespread than has been previously stressed. These findings document an FTD-specific cerebral involvement and facilitate differential diagnosis of degenerative dementias.     

Frontal lobe hypometabolism and depression in Alzheimer''s disease

PURPOSE: It is speculated that the susceptibility to urothelial cancer in dye workers who are exposed to aromatic amines is affected not only by occupational environmental factors but by host specific factors. We evaluated the interaction between glutathione S-transferase M1 gene deficiency and the occupational environmental factors associated with urothelial cancer. MATERIALS AND METHODS: The study included 137 workers who had prior exposure to dyestuff intermediates, of whom 36 had urothelial cancer. The prevalence of a glutathione S-transferase M1 gene polymorphism was investigated using polymerase chain reaction. The relationship between the glutathione S-transferase M1 0/0 gene and occupational environmental factors in the onset of urothelial cancer was examined by multivariate analysis. RESULTS: The prevalence of glutathione S-transferase M1 gene deficiency did not differ significantly between the urothelial cancer (21 cases, 58.3%) group and the cancer-free (47, 46.3%) group. It was estimated that 29.6% of the urothelial cancers in these dye workers was attributable to the glutathione S-transferase M1 0/0 gene. Analysis using multiple logistic models showed low predictive ability for urothelial cancer due to glutathione S-transferase M1 gene deficiency (p = 0.084, odds ratio 2.260, 95% confidence interval [CI] 0.904 to 5.652). A history of working in small factories (p = 0.000, odds ratio 7.404, 95% CI 2.854 to 19.206) and a long period of exposure (p = 0.016, odds ratio 5.051, 95% CI 1.371 to 18.612) significantly predicted cancer. CONCLUSIONS: We demonstrated a strong trend using the multiple logistic analysis of the contribution of glutathione S-transferase M1 gene polymorphism and occupational environmental factors. Therefore, the glutathione S-transferase M1 enzyme might have an important role in the detoxification of aromatic amine derived carcinogens. Occupational environmental factors, however, might contribute more than a glutathione S-transferase M1 gene deficiency to the occurrence of urothelial cancer among individuals exposed to aromatic amines, because of the extremely potent carcinogenicity of some occupational environmental factors.     

A Hamiltonian formulation for coupled-wave equations

We construct a Hamiltonian formulation for coupled-wave equations that describes the envelope functions of the electric field in an almost-periodic distributed-feedback waveguide with gain or loss. From the Hamiltonian, we can derive that the determinant of the fundamental matrix of the waveguide is always unity. A perturbation formula for the eigenvalues of the coupled-wave equations is simply derived using the Hamiltonian formulation. The Hamiltonian also provides the basis for the numerical calculation of the eigenvalues using the variational method