高対塩性オオムギ品種の選抜

In order to select higher salt tolerant cultivars of barley,solution culture experiments were carried out with 500 barley cultivars, which were preliminarily selected from 4581 cultivars by exposure to 1-2% of sodium chloride(MaCl) during the germinating stage. The concentrations of NaCl used in the experiments were 2 (control), 150 and 300 mM in nutrient solution.From the results of five solution culture experiments, each of which was carried out with about 100 cultivars, 105 cultivars of barley were selected as relatively about 100 cultivars. Then the final selection was carried out on those 105 cultivars, and it was found that more than 10 cultivars were highly salt tolerant, mainly based on the comparisons of shoot yields under the supply of 300 mM of NaCl.High salt tolerant barley cultivars mentioned above showed 42-86% and 17-30% of the control in shoot yield under the condition of 150 and 300 mM of NaCl, respectively.On three groups of barley,each having more than 10 cultivars, which are high, moderate and low in salt tolerance, ion contents of the plants were analyzed.The results suggest that potassium(K) uptake was comparatively larger in the high salt tolerant goup of barley cultivars,through there was a big variation in sodium(Na) and K contents even within the same group.耐塩性品種を選抜するため、500品種のオオムギを用い、水耕栽培実験を行った。培地の塩化ナトリウム濃度は2（対照区）、150および300mMとした。用いた品種500品種は、4581品種のオオムギから、発芽時の耐塩性の高い品種として選抜されたものである。1回に約100品種を用い、5回の水耕栽培実験で耐塩性の高い105品種を選抜した。この105品種を同一時期に水耕栽培し、主として塩化ナトリウム300mMでの地上部収量を比較することにより、最終選抜を行った。その結果、10余品種の高対塩性オオムギが得られた。これらの高対塩性オオムギ品種では、塩化ナトリウム150mMの場合に、対照区の42～86％、300mMの場合に対照区の17～30％の地上部収量が得られた。これらの実験に用いたオオムギ品種から、対塩性の高いもの、中程度のもの、および低いものを各々10数品種選び、それらのイオン含量を測定した。その結果、同一グループ内でもイオン含量にかなりの変動が見られるが、対塩性の高いグループでは、オオムギのナトリウム吸収に比較し、カリウム吸収の大きい傾向を認めた

Mode of disulfide bond formation of a heat-stable enterotoxin (STh) produced by a human strain of enterotoxigenic Escherichia coli

AbstractTo determine the modes of three disulfide linkages in the heat-stable enterotoxin (STh) produced by a human strain of enterotoxigenic Escherichia coli, we synthesized STh(6–18), which consists of 13 amino acid residues and has the same intramolecular disulfide linkages as native STh [(1985) FEBS Lett. 181, 138–142], by stepwise and selective formation of disulfide bonds using different types of removable protecting groups for the Cys residues. Synthesis of the peptide with different modes of disulfide bond formation provided three peptides consistent with standard STh(6–18) in their physicochemical and biological properties, thereby indicating that the disulfide bonds in STh(6–18) are

Peptide-conjugate antisense based splice-correction for Duchenne muscular dystrophy and other neuromuscular diseases

Duchenne muscular dystrophy (DMD) is an X-linked disorder characterized by progressive muscle degeneration, caused by the absence of dystrophin. Exon skipping by antisense oligonucleotides (ASOs) has recently gained recognition as therapeutic approach in DMD. Conjugation of a peptide to the phosphorodiamidate morpholino backbone (PMO) of ASOs generated the peptide-conjugated PMOs (PPMOs) that exhibit a dramatically improved pharmacokinetic profile. When tested in animal models, PPMOs demonstrate effective exon skipping in target muscles and prolonged duration of dystrophin restoration after a treatment regime. Herein we summarize the main pathophysiological features of DMD and the emergence of PPMOs as promising exon skipping agents aiming to rescue defective gene expression in DMD and other neuromuscular diseases. The listed PPMO laboratory findings correspond to latest trends in the field and highlight the obstacles that must be overcome prior to translating the animal-based research into clinical trials tailored to the needs of patients suffering from neuromuscular diseases

Development of congenic strains of mice carrying amyloidogenic apolipoprotein A-II (Apoa2c) Apoa2c reduces the plasma level and the size of high density lipoprotein

AbstractA congenic strain of mice with amyloidogenic apolipoprotein A-II (Apoa2c) on the genetic background of the amyloidosis-resistant SAM-R/1 strain was produced by 12 generations of backcrossing. Genome mapping using endogenous murine leukemia proviral markers was done in the congenic strain, termed R1·P1-Apoa2c. We confirmed that only a small region surrounding the apoA-II gene on chromosome 1 was transferred from the genome of the donor SAM-P/1 strain. The level and particle size of plasma high density lipoprotein were decreased in RI · Pl-Apoa2c mice compared to those in the progenitor SAM-R/1 mice. The function of apoA-II can be studied using this strain of mice

Oxidants induce transcriptional activation of manganese superoxide dismutase in glomerular cells

Oxidants induce transcriptional activation of manganese superoxide dismutase in glomerular cells. Cultured rat glomerular mesangial and epithelial cells and bovine glomerular endothelial cells were exposed to various concentrations of hydrogen peroxide (H2O2). Mesangial cells treated with 10 to 100 µM H2O2 for 24 hours showed a two- to ninefold increase in Mn-SOD mRNA expression associated with significantly (P < 0.005) increased Mn-SOD activity (22.2 ± 1.2 and 12.2 ± 0.7 µ/mg protein for H2O2 100 µM treated and untreated cells, respectively). In contrast, expression of Cu-Zn SOD and β-actin mRNA was not affected by H2O2. Induction of Mn-SOD mRNA by H2O2 was inhibited by actinomycin-D (4 µM) treatment. Glomerular endothelial cells also showed an increase in Mn-SOD mRNA expression following 100 µM H2O2 treatment, as did glomerular epithelial cells following treatment with 500 and 1000 µM H2O2 but not with 100 µM. Transcriptional activity of the Mn-SOD gene was assessed with a fusion reporter gene consisting of a luciferase gene (pGL2P) and a 1.2 kb fragment from the rat Mn-SOD genomic DNA (-806 to +408 bp of the transcription initiation site, -806:+408). The construct was transfected into rat glomerular mesangial and epithelial cells. Mesangial and epithelial cells transfected with pGL2P (-806:+408) and treated with H2O2 (100 µM and 1 mM for mesangial and epithelial cells, respectively) demonstrated some threefold increase in luciferase activity, whereas cells transfected with pGL2P lacking the Mn-SOD fragment did not show changes in luciferase activity following H2O2 treatment. Other oxidants, namely α- and β-naphthoflavone (50 µM to mesangial cells) and puromycin aminonucleoside (25 to 50 µg/ml to epithelial cells), also induced transcriptional activation (2- to 5-fold increase) in these cells. Thus, Mn-SOD levels in glomerular cells are enhanced when they are exposed to oxidant stress, and this up-regulation involves transcriptional activation. Further, the Mn-SOD gene contains enhancer element(s) which respond to diverse oxidant stress. The inducibility by oxidants of local Mn-SOD demonstrates that glomerular SOD may play a decisive role in the pathogenesis of glomerular injuries in which the balance between oxidants and antioxidants is critical

The effect of leg hyperthermia using far infrared rays in bedridden subjects with type 2 diabetes mellitus

We examined the effect of leg hyperthermia on oxidative stress in bedridden subjects with type 2 diabetes mellitus using 15-min sessions of far infrared rays over a two-week period. Four subjects (male 1, female 3) incapacitated by a stroke were recruited for this study. All patients were admitted to Takahashi Central Hospital and ate the same hospital meals. Fasting plasma glucose, HbA1c, tumor necrosis factor (TNF)alpha, free fatty acid, leptin, adiponectin and plasma 8-epi-prostaglandin F2alpha (8-epi-PGF2alpha) levels as a marker of oxidative stress were measured on admission, just before and 2 weeks after local heating of the leg. Results showed that plasma total 8-epi-PGF2alpha levels were decreased significantly while TNFalpha levels were increased significantly. On the other hand, glucose, HbA1c, free fatty acid, leptin and adiponectin levels were not changed during the study period. These results suggest that repeated leg hyperthermia may protect against oxidative stress.</p

Amino acid sequence of heat-stable enterotoxin produced by Vibrio cholerae non-01

AbstractThe amino acid sequence of heat-stable enterotoxin, produced by Vibrio cholerae non-01 and isolated from its culture supernatant, was determined by both Edman degradation of native and reductively carboxy-methylated enterotoxin and also a combination of fast atom bombardment mass spectrometry and carboxy-peptidase Y digestion of native enterotoxin to be as follows: Ile-Asp-Cys-Cys-Glu-Ile-Cys-Cys-Asn-Pro-Ala-Cys-Phe-Gly-Cys-Leu-Asn. This sequence is very similar, but not identical, to those of heat-stable enterotoxins produced by enterotoxigenic Escherichia coli and Yersinia enterocolitica