Predictor of buckwheat allergy in children based on challenge test results: a retrospective observational study in Japan.

Summary: Background. Buckwheat (BW) is a major food allergen and one of the leading causes of food-induced anaphylaxis in Japan. The standard method of diagnosing food allergy is the oral food challenge (OFC). The BW-specific IgE (BW-sIgE) value is used to assess BW allergy but its utility is limited. Aim. The aim of the present study was to identify factors with predictive value for the diagnosis of BW allergy using the OFC. Methods. We evaluated 37 patients who were classified into the positive or negative group according to their OFC results. Results. Ten patients (27.0%) showed objective or persistent, moderate, subjective symptoms during the OFC. The positive group had a significantly higher BW-sIgE/total IgE ratio than the negative group (p less than 0.001), but the total IgE (p = 0.139) and BW-sIgE (p = 0.130) did not differ significantly. Receiver operator characteristic (ROC) analysis showed that the BW-sIgE/total IgE ratio had a larger area under the curve (AUC, 0.885) than BW-sIgE (AUC, 0.667). The statistically optimal cut-off was 0.0058 for the BW-sIgE/total IgE ratio, which corresponded to a clinical sensitivity and specificity of 90.0% and 81.5%, respectively. Conclusions. BW-sIgE/total IgE ratio may be more useful predictor of BW OFC results than BWs-IgE.

Effect of vitamin D supplementation on pegylated interferon/ribavirin therapy for chronic hepatitis C genotype 1b: a randomized controlled trial.

Chronic HCV-infected patients tend to have vitamin D deficiency, suggesting that vitamin D supplementation may enhance the efficacy of treatment with pegylated interferon (PEG-IFN) and ribavirin (RBV). We therefore assessed the effects of vitamin D supplementation on viral response to PEG-IFN/RBV. Eighty-four patients with HCV genotype 1b were randomized, 42 to oral vitamin D supplementation (1000 IU/day) and 42 to nonsupplementation (control), from week 8 to the end of PEG-IFN/RBV therapy. The primary end point was undetectable HCV RNA at week 24 (viral response [VR]). VR rate at week 24 was significantly higher in the vitamin D than in the control group (78.6% vs 54.8% P = 0.037). Adverse events were similar in both groups. When patients were subdivided by IL28B SNP rs8099917 genotype, those with the TT genotype group showed a significantly higher VR rate at week 24 with than without vitamin D supplementation (86.2% vs 63.3% vs P = 0.044). Although patients with the TG/GG genotype, who were relatively resistant to PEG-IFN treatment, had similar VR rates at week 24 with and without vitamin D supplementation, the decline in viral load from week 8 to week 24 was significantly greater with than without vitamin D supplementation. Multivariate analysis showed that rs8099917 genotype and vitamin D supplementation contributed significantly to VR at week 24. SVR rates were similar in the vitamin D and control groups [64.3% (27/42) vs 50% (21/42), P = 0.19]. Vitamin D supplementation may enhance the effects of PEG-IFN/RBV in HCV genotype 1b-infected patients.

Effects of dietary bovine lactoferrin on growth, physiological performance, iron metabolism and non-specific immune responses of Siberian sturgeon Acipenser baeri.

The present experiment was carried out to investigate the effects of different levels of dietary lactoferrin (LF) on growth performance, physiological status, iron absorption and innate immune response of juvenile Siberian sturgeon Acipenser baeri. Fish were fed with six different rations including 0, 100, 200, 400, 800 and 1600 mg LF kg(-1) diet for 8 weeks. At the end of the experiment, samples were collected for estimating the physiological and immunological parameters. Dietary LF did not change the fish growth performance, hematological parameters, serum proteins or hepatic enzymes. Moreover, stress indicators (plasma cortisol, glucose and lactate) were not affected by dietary LF. The iron absorption of fish was considerably affected by LF; thus, plasma iron in LF-treatments greatly declined and the total iron binding capacity (TIBC) significantly increased in fish fed with 800 mg LF kg(-1). In addition, the liver iron content markedly increased in some LF-treatments, but the variation of muscle iron concentration in treatments was insignificant. The amount of mucus secretion and serum bactericidal activity rose in fish fed on dietary LF, although other non-specific immune responses such as mucus bactericidal activity, serum and mucus lysozyme activity, serum peroxidase, serum natural hemolytic complement activity and serum IgM were not influenced by LF. This study revealed the ability of dietary LF to sequester iron, which is an essential nutrient required for the growth of bacteria. LF was also shown to improve some physiological and immunological parameters of Siberian sturgeon, to some extent.

Crystal structure of human AUH protein, a single-stranded RNA binding homolog of enoyl-CoA hydratase.

BACKGROUND: The AU binding homolog of enoyl-CoA hydratase (AUH) is a bifunctional protein that has two distinct activities: AUH binds to RNA and weakly catalyzes the hydration of 2-trans-enoyl-coenzyme A (enoyl-CoA). AUH has no sequence similarity with other known RNA binding proteins, but it has considerable sequence similarity with enoyl-CoA hydratase. A segment of AUH, named the R peptide, binds to RNA. However, the mechanism of the RNA binding activity of AUH remains to be elucidated. RESULTS: We determined the crystal structure of human AUH at 2.2 A resolution. AUH adopts the typical fold of the enoyl-CoA hydratase/isomerase superfamily and forms a hexamer as a dimer of trimers. Interestingly, the surface of the AUH hexamer is positively charged, in striking contrast to the negatively charged surfaces of the other members of the superfamily. Furthermore, wide clefts are uniquely formed between the two trimers of AUH and are highly positively charged with the Lys residues in alpha helix H1, which is located on the edge of the cleft and contains the majority of the R peptide. A mutational analysis showed that the lysine residues in alpha helix H1 are essential to the RNA binding activity of AUH. CONCLUSIONS: Alpha helix H1 exposes a row of Lys residues on the solvent-accessible surface. These characteristic Lys residues are named the "lysine comb." The distances between these Lys residues are similar to those between the RNA phosphate groups, suggesting that the lysine comb may continuously bind to a single-stranded RNA. The clefts between the trimers may provide spaces sufficient to accommodate the RNA bases.

The molecular genetics and evolution of red and green color vision in vertebrates.

To better understand the evolution of red-green color vision in vertebrates, we inferred the amino acid sequences of the ancestral pigments of 11 selected visual pigments: the LWS pigments of cave fish (Astyanax fasciatus), frog (Xenopus laevis), chicken (Gallus gallus), chameleon (Anolis carolinensis), goat (Capra hircus), and human (Homo sapiens);and the MWS pigments of cave fish, gecko (Gekko gekko), mouse (Mus musculus), squirrel (Sciurus carolinensis), and human. We constructed these ancestral pigments by introducing the necessary mutations into contemporary pigments and evaluated their absorption spectra using an in vitro assay. The results show that the common ancestor of vertebrates and most other ancestors had LWS pigments. Multiple regression analyses of ancestral and contemporary MWS and LWS pigments show that single mutations S180A, H197Y, Y277F, T285A, A308S, and double mutations S180A/H197Y shift the lambda(max) of the pigments by -7, -28, -8, -15, -27, and 11 nm, respectively. It is most likely that this "five-sites" rule is the molecular basis of spectral tuning in the MWS and LWS pigments during vertebrate evolution.

Further evidence for the involvement of insulin receptor substrates in epidermal growth factor-induced activation of phosphatidylinositol 3-kinase.

In accordance with our recent results obtained with cultured rat hepatocytes [Fujioka, T. & Ui, M. (2001) Eur. J. Biochem. 268, 25-34], epidermal growth factor (EGF) gave rise to transient tyrosine phosphorylation of insulin receptor substrates (IRS-1 and IRS-2), thereby activating the bound phosphatidylinositol 3-kinase in human epidermoid carcinoma A431 cells normally abundant in EGF receptors (EGFR) and Chinese hamster ovary (CHO) cells transfected with full-length EGFR. These actions of EGF, although much smaller in magnitude than those of insulin or IGF-I in the same cells, were accompanied by tyrosine phosphorylation of EGFR rather than insulin or IGF-I receptors, never observed in wild-type CHO cells expressing no EGFR, and totally inhibited by an inhibitor of EGFR kinase, AG1478, that was without effect on insulin or IGF-I actions. Recombinant IRS-1 was phosphorylated on tyrosines upon incubation with purified EGFR from A431 cells and 32P-labeled ATP. When CHO cells were transfected with C-terminal truncated EGFR lacking three NPXY motifs responsible for direct binding to phosphotyrosine-binding domains of IRSs, no effect of EGF could be observed. We suggest that tyrosine phosphorylation of IRS-1 or IRS-2 could mediate EGFR-induced activation of phosphatidylinositol 3-kinase in mammalian cells.

[Effect of autologous platelet-rich plasma (PRP) in cardiac surgery].

Autologous platelet-rich plasma (PRP) was harvested before cardiopulmonary bypass (CPB). After heparin neutralization, it was returned to patients. The purpose of this study was to examine platelet function and the amount of blood loss and blood transfusion after transfusion of PRP. Twenty-eight patients undergoing elective coronary artery bypass grafting and other procedures were divided into three groups: group A; patients undergoing CAGB between May and October 1997 (n = 10), group B; patients undergoing other between May and October 1997 (n = 8), group C; patients undergoing CAGB before May 1997 (n = 10). Blood cell count, platelet aggregation in response to ADP, and platelet adhesion were measured before CPB, just after CPB, after infusion of protamine and PRP, 24 hrs after CPB and 48 hrs after CPB. Blood loss and blood transfusion in group. A and group C were examined after CPB. There was no significant difference in platelet count between group A and group B. There was significant difference in platelet aggregation in group A. There was no significant difference in blood loss after CPB between group A and group C, but there was a significant difference in blood transfusion between group A and group C. These results suggest that PRP was useful to preserve platelet function and to decrease blood loss after CPB in cardiac surgery.

Inhibitory effect of epigallocatechin-gallate on brain tumor cell lines in vitro.

We investigated the effect of epigallocatechin-gallate (EGCG), the main constituent of green tea polyphenols, on human glioblastoma cell lines U-373 MG and U-87 MG, rat glioma cell line C6, and rat nonfunctioning pituitary adenoma cell line MtT/E. Cell viability was determined by assay with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), and the extent of apoptosis was studied by flow cytometric analysis. Apoptosis was also characterized by morphology using fluorescent microscopy. The role of insulin-like growth factor-I (IGF-I) was studied by assay with MTT, immunohistochemistry, and immunoradiometric assay. After 72-h exposure, a statistically significant loss of viability (P = < 0.0001) was observed at concentrations of 12.5, 25, 50, and 100 microg/ml in U-373 MG cells and U-87 MG cells. EGCG at concentrations of 50 microg/ml and higher significantly reduced the viability of C6 cells. EGCG inhibited viability of MtT/E cells only at a concentration of 100 microg/ml. Quantitative study by flow cytometry demonstrated that lower doses of EGCG (12.5, 25, 50 microg/ml) induced apoptosis in U-373 MG, U-87 MG, and C6 cells; however, only the highest dose (100 microg/ml) induced apoptosis in MtT/E cells. Compared with other cell lines, MtT/E cells showed stronger IGF-I immunoreactivity. Neutralization of IGF-I with an antihuman IGF-I antibody reduced viability of the cell lines. It can be concluded that EGCG has an inhibitory effect on malignant brain tumors, and IGF-I may be involved in the effects of EGCG.

Bilateral thalamic glioma: case report.

We report a 63-year-old man who had a rare bilateral thalamic glioma. He complained of difficulty with calculations and had mental deterioration. T1-weighted images revealed bilateral thalamic swelling with homogeneous low signal and no contrast enhancement. The tumour, showing decrease of N-acetylaspartate and the presence of lactate on magnetic resonance spectroscopy, was diagnosed as an astrocytoma by stereotactic biopsy.

The likely transformation of papillary thyroid carcinoma into anaplastic carcinoma during postoperative radioactive iodine-131 therapy: report of a case.

We report herein a case of papillary carcinoma which appeared to transform into anaplastic carcinoma during postoperative radioactive iodine-131 (131I) therapy. A 67-year-old man who was diagnosed as having papillary thyroid carcinoma with bilateral neck lymph node involvement and multiple lung metastases underwent total thyroidectomy prior to 131I therapy. Immediately after a second course of 131I therapy, the patient complained of right neck pain and swelling, and a biopsy of the swollen neck lymph node was taken. Histologic examination of this biopsy specimen revealed anaplastic carcinoma. With p53 immunohistochemical staining, both the primary tumor and the biopsy specimen were positive. We speculate that first, some DNA damage in tumor cells was induced by the initial 131I therapy, but neither DNA repair nor cell apoptosis occurred because the p53 gene was already mutated; then further DNA damage was induced by the second 131I therapy, leading to anaplastic transformation.

Postoperative chemotherapy in elderly patients with advanced gastric cancer.

BACKGROUND/AIMS: The definitive efficacy of postoperative chemotherapy in elderly patients with advanced gastric cancer has not been established. The aim of this study is to evaluate prognosis in elderly patients with advanced gastric cancer and the effect of postoperative chemotherapy on prognosis. METHODOLOGY: Fifty-three patients, 75 years of age or older who underwent curative surgery for advanced gastric cancer were divided into 14 patients with postoperative chemotherapy (chemotherapy group) and 39 patients without postoperative chemotherapy (control group). Chemotherapy regimens were as follows: oral 5-FU alone (n = 11), intravenous mitomycin plus 5-FU: MF (n = 2), and MF plus oral 5-FU (n = 1). No prior chemotherapy or radiation was given. RESULTS: There were no significant differences of clinical and pathological backgrounds between the two groups. The rate of death due to recurrent carcinoma was 50.0% in the chemotherapy group and 43.6% in the control group, the difference being insignificant. Although the median survival time of the chemotherapy group (40.4 months) was longer than in the control group (31.7 months), a significant difference did not exist between the groups. The 1-, 3-, and 5-year survival rates did not significantly differ between the chemotherapy group versus the control group, 85.7% versus 82.1%, 42.9% versus 51.3%, and 35.7% versus 46.2%, respectively. CONCLUSIONS: Postoperative chemotherapy did not contribute to prolong survival in elderly patients with advanced gastric cancer mainly because the incidence of recurrent carcinoma was not reduced.

KCR1, a membrane protein that facilitates functional expression of non-inactivating K+ currents associates with rat EAG voltage-dependent K+ channels.

Cerebellar granule neurons possess a non-inactivating K+ current, which controls resting membrane potentials and modulates the firing rate by means of muscarinic agonists. kcr1 was cloned from the cerebellar cDNA library by suppression cloning. KCR1 is a novel protein with 12 putative transmembrane domains and enhances the functional expression of the cerebellar non-inactivating K+ current in Xenopus oocytes. KCR1 also accelerates the activation of rat EAG K+ channels expressed in Xenopus oocytes or in COS-7 cells. Far-Western blotting revealed that KCR1 and EAG proteins interacted with each other by means of their C-terminal regions. These results suggest that KCR1 is the regulatory component of non-inactivating K+ channels.

Tomosyn: a syntaxin-1-binding protein that forms a novel complex in the neurotransmitter release process.

Syntaxin-1 is a component of the synaptic vesicle docking and/or membrane fusion soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) complex (7S and 20S complexes) in nerve terminals. Syntaxin-1 also forms a heterodimer with Munc18/n-Sec1/rbSec1 in a complex that is distinct from the 7S and 20S complexes. In this report, we identify a novel syntaxin-1-binding protein, tomosyn, that is capable of dissociating Munc18 from syntaxin-1 and forming a novel 10S complex with syntaxin-1, soluble N-etyhlmaleimide-sensitive factor attachment (SNAP) 25, and synaptotagmin. The 130 kDa isoform of tomosyn is specifically expressed in brain, where its distribution partly overlaps with that of syntaxin-1 in nerve terminals. High level expression of either syntaxin-1 or tomosyn results in a specific reduction in Ca2+-dependent exocytosis from PC12 cells. These results suggest that tomosyn is an important component in the neurotransmitter release process where it may stimulate SNARE complex formation.

Carcinoembryonic antigen and intra-arterial chemotherapy response of liver metastases.

BACKGROUND/AIMS: We investigated the relationship between serum carcinoembryonic antigen and response to hepatic artery chemotherapy for unresectable colorectal liver metastases. METHODOLOGY: The study included 14 patients with unresectable colorectal liver metastases receiving hepatic arterial chemotherapy weekly. Patients were evaluated monthly including liver function tests and carcinoembryonic antigen. Ten patients received high dose 5-fluorouracil (1000 mg/m2) and 4 patients received other regimens. One patient underwent hepatectomy for cure after 5-fluorouracil. RESULTS: Thirteen patients (93%) had normal quality of life without toxicity during hepatic artery infusion. Response rate in the high dose 5-fluorouracil group was 50%, while the response rate of other regimens was 25%. Mean survival time differed between responding (n = 6) and non-responding patients (n = 8) (527 vs 289 days), and the high dose 5-fluorouracil (n = 10) and other regimens (n = 4) (462 vs 213 days). In responding patients, peak serum carcinoembryonic antigen levels before hepatic artery infusion decreased within 6 months. In the non-responding patients, serum carcinoembryonic antigen levels increased rapidly despite hepatic artery infusion. CONCLUSIONS: Serum carcinoembryonic antigen levels correlated well with response. Hepatic artery infusional chemotherapy with high dose 5-fluorouracil may be recommended as effective treatment for unresectable liver metastasis from colorectal cancer if serum carcinoembryonic antigen levels decrease within 6 months.

Knocking out a specific tRNA species within unfractionated Escherichia coli tRNA by using antisense (complementary) oligodeoxyribonucleotides.

Methods for the preparation of an Escherichia coli tRNA mixture lacking one or a few specific tRNA species can be the basis for future applications of cell-free protein synthesis. We demonstrate here that virtually a single tRNA species in a crude E. coli tRNA mixture can be knocked out by an antisense (complementary) oligodeoxyribonucleotide. One out of five oligomers complementary to tRNA(Asp) blocked the aspartylation almost completely, while minimally affecting the aminoacylation with other 13 amino acids tested. This 'knockout' tRNA behaved similarly to the untreated tRNA in a cell-free translation of an mRNA lacking Asp codons.

Hairpin structure of an RNA 28-mer, which contains a sequence of the enzyme component of a hammerhead ribozyme system: evidence for tandem G:A pairs that are not of side-by-side type.

An RNA 28-mer (Rz28) was obtained as a major product by in vitro transcription with T7 RNA polymerase of a promoter-template DNA, which contains a sequence for the enzyme component, RNA 24-mer (Rz24), of a mutant hammerhead ribozyme system. Sequence analysis and enzymatic probing study showed that Rz28 has 4 extra nucleotides at the 3'-terminus, the sequence of which is complementary to that of the 5'-terminal sequence of Rz24, and forms a stable hairpin structure. NMR studies using a 15N-guanine-labeled derivative suggested that Rz28 contains tandem G:A pairs that are not of the side-by-side type which is found in the crystal structure of hammerhead ribozyme complexes. Comparison of the HMQC spectra of 15N-guanine-labeled Rz28 and Rz24 suggested that Rz24 also contains the same type of tandem G:A pairs.

[Benign infantile mitochondrial myopathy caused by reversible cytochrome c oxidase deficiency].

A 2-month-old girl had generalized weakness, profound muscular hypotonia, hepatomegaly and severe lactic acidosis. She needed ventilatory support. Muscle specimen taken at 2 months showed ragged-red fibers, abnormal mitochondria, and reduced cytochrome c oxidase (CCO) staining Biochemical analysis showed CCO activity to be reduced to about 16% of the normal mean. She received carnitine and coenzyme Q10 supplementation from the age of 3 months and abnormal blood lactate values declined to near normal values during the first three weeks. Gradually her condition started to improved: she held her head at 9 months, and walked alone at 15 months. The second biopsy specimen at 3 years and 8 months showed almost normal CCO staining and she was free of clinical signs. This case is an example of a rare benign infantile mitochondrial myopathy caused by CCO deficiency. Early diagnosis is crucial to provide intensive treatment until spontaneous clinical improvement appears. We concluded that carnitine and coenzyme Q10 supplementation was a useful treatment for clinical improvement in patients with a benign infantile mitochondrial myopathy caused by CCO deficiency.

A highly efficient cell-free protein synthesis system from Escherichia coli.

We modified a cell-free coupled transcription/translation system from Escherichia coli with the T7 phage RNA polymerase, and achieved a productivity as high as 0.4 mg protein/ml reaction mixture. First, we found that the optimal concentrations of phosphoenolpyruvate and poly(ethylene glycol) are interdependent; higher concentrations of the former should be used at higher concentrations of the latter. Second, the use of a condensed 30000 x g cell extract, in place of the conventional one, significantly increased the initial rate of protein synthesis. This phenomenon was demonstrated to be due to a reason other than elimination of inhibitory molecule(s) from the extract. For this system with the condensed extract, the phosphoenolpyruvate and poly(ethylene glycol) concentrations were again co-optimized, resulting in production of chloramphenicol acetyltransferase at a productivity of 0.3 mg/ml. Finally, the productivity was further increased up to 0.4 mg/ml, by supplementation of the pool of amino acids. This improved cell-free protein synthesis system is superior in productivity to any other cell-free systems reported so far, including the continuous-flow cell-free system.

Whole-cell analysis of NGK2 (mKv3.1a) K+ channels stably expressed in mouse fibroblast cells.

NGK2 (mKv3.1a) K+ channel cDNA was introduced into mouse B82 fibroblast cells to express in a mammalian system. The NGK2 current in the stably transformed fibroblast cells exhibited a high threshold for activation and slow decay with two components. The data suggest that the NGK2 channel may contribute to slowly inactivating K+ currents observed in excitable and inexcitable cells.

Rhodopsin from the fish, Astyanax: role of tyrosine 261 in the red shift.

PURPOSE: To isolate and characterize the rhodopsin cDNA from the fish, Astyanax fasciatus, and to determine the effect of tyrosine 261 on its spectral tuning. METHODS: The rhodopsin cDNA was cloned using reverse transcription-polymerase chain reaction amplification and then sequenced. A mutant, Y261F, was generated by site-directed mutagenesis. Both wild type and mutant were transiently expressed in COS-1 cells, regenerated with 11-cis retinal, and purified by immunoaffinity chromatography. Ultraviolet-visible spectrophotometry was used to determine wavelength of maximum absorption. RESULTS: A fasciatus rhodopsin cDNA exhibits 80% amino acid identity with bovine rhodopsin. In contrast to all known rhodopsins, this rhodopsin contains a tyrosine instead of a phenylalanine at amino acid position 261. Indeed, this particular amino acid replacement has been implicated in the long wavelength absorption of the red cone pigment. Site-directed mutagenesis was used to change the Astyanax amino acid 261 to phenylalanine (Y261F). Expression of the Y261F mutant in COS-1 cells showed an absorbance maximum of 496 nm, compared to 504 nm for the wild type pigment. CONCLUSIONS: A naturally occurring fish rhodopsin is red shifted about 8 nm due to one critical amino acid substitution.