Role of the accompanying anion in the effect of calcium salts on potassium uptake by excised barley roots

The effect of addition of Ca salts on accumulation of K from 5 mN KCl or K₂SO₄ solutions was found to depend on whether Ca was added as Cl or SO₄ salt. Chloride as well as K uptake was increased when Ca and Cl concentrations in culture solutions were increased. Pre-treatment of roots with CaCl₂ stimulated subsequent K uptake from K₂SO₄ solutions as compared to pre-treatment with distilled water but pre-treatment with CaSO₄ did not. The results indicate that addition of Ca salts to KCl or K₂SO₄ solutions increased anion uptake and the effect of the addition of the Ca salts on K uptake was in part the result of increased anion uptake and not entirely a direct effect of Ca.     

Secretion of phytase from the roots of several plant species under phosphorus-deficient conditions

Phosphorus (P) deficiency increased the secretion of phytases from roots of various plant species. The secretory phytases were collected with a dialysis membrane tube for 24 hours from roots of sixteen plant species grown with low or adequate supply of P in nutrient solutions. The activity of not only secretory phytase, but also acid phosphatase, increased with the low P treatment in all of the plant species examined. Secretion of phytase by the roots under P-deficient conditions was highest in Brachiaria decumbens CIAT 606, Stylosanthes guianensis CIAT 184 and tomato, moderate in Brachiaria brizantha CIAT6780, Stylosanthes guianensis CIAT 2950, alfalfa, white clover and orchard grass, and lowest in Andropgon gayanus CIAT 621, Stylosanthes capitata CIAT 10280, upland rice, timothy, redtop, alsike clover, red clover and white lupin plants. An immunoreactive protein band that reacted with a polyclonal antibody raised against wheat bran phytase, corresponding to molecular weight 35–40 kD, could be detected in seven of the species tested. These results indicate that the secretory phytase may provide an efficient mechanism for certain plants to utilize inositol hexaphosphate in soil.     

Distribution and chemical speciation of aluminum in the Al accumulator plant,Melastoma malabathricum L.

The Al accumulation mechanisms in an Al accumulator plant, Melastoma malabathricum L. (Melastoma), was investigated. Al was located in the upper epidermal cells and also distributed in mesophyll cells in leaf sections. In root sections, Al was found in all the root tissues, particularly in the epidermis and endodermis. Al concentrations in young leaves, mature leaves, old leaves, and roots were 8.0, 9.2, 14.4, and 10.1 mg g¹, respectively. Approximately 45% of total Al in oldest leaves, and approximately 60% of total Al in leaves of other positions and roots were extracted in Tris-HCl buffer (pH 7.0). Since Al in the residual parts was mostly dissolved in hot 0.5 M H₂SO₄ containing 2% cetyl trimethylammonium bromide, residual Al seemed to consist mainly of monomeric Al and Al bound to pectic substances and hemicellulose. Al in the Tris-HCl extract consisted of non-monomeric Al (complexed form). Oxalate concentration in the Tris-HCl extract in leaves was significantly higher in the +Al treatment than in the –Al treatment and there was a positive correlation between the Al concentration and oxalate concentration. ²⁷Al NMR spectrum of fresh leaves indicated the presence in the order of monomeric Al, Al-oxalate, Al-(oxalate)₂, and Al-(oxalate)₃ in intact leaves.     

Increased proliferation of a human breast carcinoma cell line by recombinant interleukin-2

Two adenocarcinoma cell lines, Breast M25-SF and Breast M, were established from tumor tissue resected surgically from a patient with breast cancer. One, Breast M25-SF, expresses interleukin-2 receptor (IL-2R) on the cell surface and the other, Breast M, does not. The effects of recombinant inteleukin-2 (rIL-2) on the proliferation of these cell lines were investigated. The growth of Breast M25-SF was significantly promoted by rIL-2 ranging from 1,25 U/ml to 640 U/ml. Anti-CD25 (Tac) antibody, significantly blocked the growth enhancement of Breast M25-SF by rIL-2. Breast M, however, did not respond to rIL-2. To confirm more directly the promotion of Breast M25-SF growth by rIL-2, cloning of IL-2 responders from parent Breast M25-SF cells was carried out by limiting dilution without feeder cells in 96-well microplates. No colony formation was found in 24 wells without rIL-2. Eleven, 13 and 6 clones were established from groups of 24 wells containing rIL-2 at 200, 20 and 2 U/ml respectively. All of the clones expressed IL-2R and respond to rIL-2. By using a sensitive polymerase chain reaction technique, we demonstrated that Breast M25-SF but not Breast M expressed IL-2 mRNA, and IL-2 secretion from Breast M25-SF but not Breast M was also confirmed by radioimmunoassay. These findings suggest a role for IL-2 in autocrine support of Breast M25-SF growth. IL-2 may play an important role in the growth control of breast carcinoma cells.     

Deletion of ASK1 Protects against Hyperoxia-Induced Acute Lung Injury

Apoptosis signal-regulating kinase 1 (ASK1), a member of the MAPK kinase kinase kinase (MAP3K) family, is activated by various stimuli, which include oxidative stress, endoplasmic reticulum (ER) stress, calcium influx, DNA damage-inducing agents and receptor-mediated signaling through tumor necrosis factor receptor (TNFR). Inspiration of a high concentration of oxygen is a palliative therapy which counteracts hypoxemia caused by acute lung injury (ALI)-induced pulmonary edema. However, animal experiments so far have shown that hyperoxia itself could exacerbate ALI through reactive oxygen species (ROS). Our previous data indicates that ASK1 plays a pivotal role in hyperoxia-induced acute lung injury (HALI). However, it is unclear whether or not deletion of ASK1 in vivo protects against HALI. In this study, we investigated whether ASK1 deletion would lead to attenuation of HALI. Our results show that ASK1 deletion in vivo significantly suppresses hyperoxia-induced elevation of inflammatory cytokines (i.e. IL-1β and TNF-α), cell apoptosis in the lung, and recruitment of immune cells. In summary, the results from the study suggest that deletion of ASK1 in mice significantly inhibits hyperoxic lung injury.     

Discovery of pyridone-containing imidazolines as potent and selective inhibitors of neuropeptide Y Y5 receptor

A series of 2-pyridone-containing imidazoline derivatives was synthesized and evaluated as neuropeptide Y Y5 receptor antagonists. Optimization of the 2-pyridone structure on the 2-position of the imidazoline ring led to identification of 1-(difluoromethyl)-5-[(4S,5S)-4-(4-fluorophenyl)-4-(6-fluoropyridin-3-yl)-5-methyl-4,5-dihydro-1H-imidazol-2-yl]pyridin-2(1H)-one (7m). Compound 7m displayed statistically significant inhibition of food intake in an agonist-induced food intake model in SD rats and no adverse cardiovascular effects in anesthetized dogs. In addition, markedly higher brain penetrability and a lower plasma Occ90 value were observed in P-gp-deficient mdr1a (?/?) mice compared to mdr1a (+/+) mice after oral administration of 7m.     

A simple method for in vivo measurement of implant rod three-dimensional geometry during scoliosis surgery

Scoliosis is defined as a spinal pathology characterized as a three-dimensional deformity of the spine combined with vertebral rotation. Treatment for severe scoliosis is achieved when the scoliotic spine is surgically corrected and fixed using implanted rods and screws. Several studies performed biomechanical modeling and corrective forces measurements of scoliosis correction. These studies were able to predict the clinical outcome and measured the corrective forces acting on screws, however, they were not able to measure the intraoperative three-dimensional geometry of the spinal rod. In effect, the results of biomechanical modeling might not be so realistic and the corrective forces during the surgical correction procedure were intra-operatively difficult to measure. Projective geometry has been shown to be successful in the reconstruction of a three-dimensional structure using a series of images obtained from different views. In this study, we propose a new method to measure the three-dimensional geometry of an implant rod using two cameras. The reconstruction method requires only a few parameters, the included angle θ between the two cameras, the actual length of the rod in mm, and the location of points for curve fitting. The implant rod utilized in spine surgery was used to evaluate the accuracy of the current method. The three-dimensional geometry of the rod was measured from the image obtained by a scanner and compared to the proposed method using two cameras. The mean error in the reconstruction measurements ranged from 0.32 to 0.45 mm. The method presented here demonstrated the possibility of intra-operatively measuring the three-dimensional geometry of spinal rod. The proposed method could be used in surgical procedures to better understand the biomechanics of scoliosis correction through real-time measurement of three-dimensional implant rod geometry in vivo.     

不同时期叶喷植物生长调节剂对大豆花荚脱落率及多聚半乳糖醛酸酶活性的影响

在大田条件下,以大豆品种‘合丰50＇为材料,比较研究了在V3（第3节龄期,三叶期）、R1（初花期）和R3（始荚期）期叶面喷施DTA-6、S_（3307）和TIBA三种植物生长调节剂对大豆花荚脱落率及多聚半乳糖醛酸酶活性的影响。结果表明：V3期叶喷TIBA、S_（3307）、DTA降低了大豆花荚脱落率,降低了大豆花荚和脱落花荚多聚半乳糖醛酸酶活性;R1期叶喷植物生长调节剂显著降低了大豆花荚及脱落花荚中多聚半乳糖醛酸酶活性,以DTA-6调控效果最佳,S_（3307）次之;R3期叶喷植物生长调节剂降低了大豆荚及落荚的多聚半乳糖醛酸酶活性,以DTA-6调控效果最佳,TIBA次之。综合分析表明,V3、R1和R3期叶面喷施植物生长调节剂能够降低大豆花荚脱落率及多聚半乳糖醛酸酶活性,对大豆花荚的脱落有一定的调控作用,有利于提高产量,其综合调控效果为,V3期：S_（3307）〉DTA-6〉TIBA〉CK;R1期：DTA-6〉TIBA〉S_（3307）〉CK;R3期：DTA-6〉TIBA〉S_（3307）〉CK。     

Nutritional characteristics in leaves of native plants grown in acid sulfate,peat, sandy podzolic,and saline soils distributed in Peninsular Thailand

Acid sulfate soils, peat soils, sandy podzolic, and saline soils are widely distributed in Peninsular Thailand. Native plants adapted to such problem soils have grown well, and showed no symptom of mineral deficiency or toxicity. Dominant plants growing in low pH soils (acid sulfate and peat) were Melastoma marabathricum and Melaleuca cajuputi. Since M. marabathricum accumulated a huge amount of aluminum (Al) in leaves, especially in new growing leaves, it can be designated an Al accumulator plant. While M. cajuputi did not accumulate Al in shoot, it can be designated an Al excluder plant. Both plant species adapted well to low pH soils, though a different strategy was used for Al. On the other hand, in acid sulfate and peat soils, M. cajuputi, Panicum repens, Cyperus haspan, and Ischaemum aristatum accumulated large amounts of Na in the leaves (or shoots), even in soil with low exchangeable Na concentration. Thus, when growing in the presence of high Al and Na concentration in soils, plant species have developed two opposite strategies: (1) Al or Na accumulation in the leaf and (2) Al or Na exclusion from the leaf. Al concentration in leaves had a negative relationship with the other mineral nutrients except for N and Mn, and Na concentration in leaves also had a negative relationship with P, Zn, Mn, Cu, and Al. Consequently, Al and Na accumulator plants are characterized by their exclusion of other minerals from their leaves.     

Estimating nanoscale deformation in bone by X-ray diffraction imaging method

Knowledge of internal stress-strain in bone tissue is important for clinical diagnosis and remedies. The inorganic mineral phase of apatite crystals in bone composite, because of its crystalline nature, provides a reliable way of measurement through X-ray diffraction system. Use of two-dimensional detector, imaging plate (IP), is considered to expedite the process with much more information, hence, is widely applied in the study of organization, stress, strain, etc. for crystalline substance. The distortion of Debye rings in the image obtained by IP can be directly related to the deformation in lattice plane of the crystals. Since X-ray diffraction method involves measurement at nano-level, proper focus on the extraction of data and corresponding analysis is needed. In the current work, we considered weighted average value of intensity to locate radius vectors along azimuthal direction in the diffracted rings from the primary array of digital data in steps of pixels. The widely applied approaches for profile shift measurement--peak shift and full width at half maximum (FWHM) of a peak, and shift of center of gravity of profile--were compared with a new concept of segmental shift (SS) proposed previously by the authors. We observed reliable and effective outcomes with higher precision in the consideration of SS while using IP as a detector. Our approach in this work for intensity integration and radius vector positioning especially add precision in such applications.