Aerodynamic advantages of upside down take-off for aerial dispersal in Tetranychus spider mites.

Aerial dispersal may be important for redistribution of spider mites into new habitats. Evidence for behavioral control of aerial take-off has been well documented for Tetranychus urticae Koch. Before aerial dispersal they exhibit the aerial take-off posture that involves lifting the forelegs upright and raising the forebody. However, whether the aerial take-off posture functions to increase drag has remained unclear. The objectives of this study were to clarify: (i) aerodynamic effects of the aerial take-off posture; and (ii) actual aerial take-off behavior in T. urticae. To evaluate the aerodynamic forces experienced by grounded spider mites in different postures, we constructed three-dimensional models of T. urticae, exhibiting the aerial take-off posture and the normal posture, using computer graphics. We found that the aerial take-off posture was effective in receiving greater rearward forces from wind rather than upward forces. As a result, aerial take-off from a horizontal platform is unlikely. Instead, inverted departure surfaces, e.g., lower leaf surfaces, with inclines are likely to be effective sites for take-off. Laboratory experiments and field observations indicated that the mites preferentially adopted such a position for orientation and take-off. Our findings provided a rationale for the take-off behavior of Tetranychus spider mites.

Prevention of corticosteroid-induced osteonecrosis in rabbits by intra-bone marrow injection of autologous bone marrow cells.

OBJECTIVES: Femoral head osteonecrosis (ON) is a serious complication of steroid administration. We evaluated bone marrow transplantation (BMT) for preventing corticosteroid-induced ON. METHODS: Rabbits, injected with methylprednisolone (MPSL; 20 mg/kg), were divided into four groups: (i) MPSL alone; MPSL injection only, (ii) MPSL+needling; 2 days after MPSL injection, a hole (1.2 mm diameter) was drilled from the outer cortex 2.5 cm distal to the proximal end of the greater trochanter, (iii) MPSL+saline; 2 days after MPSL injection, 2 ml saline was injected directly into the bone marrow cavity, and (iv) MPSL+BMT; 2 days after MPSL injection, 1 x 10(7)/2 ml bone marrow cells (BMCs) were injected directly into the bone marrow cavity. Platelets, fibrinogen, prothrombin time and total cholesterol in peripheral blood were measured before and after treatment. Tissues were stained with haematoxylin and eosion and terminal deoxynucleotidyl-mediated deoxyuridine triphosphate nick-end labelling stain and immunostained for VEGF, while cell proliferation and viability of whole BMCs in the femur were analysed by cell cycle analysis and [(3)H]-thymidine uptake. RESULTS: The ON incidence in rabbits treated with MPSL alone, MPSL+needling and MPSL+saline was 72.7, 70.0 and 66.7%, respectively, while in the MPSL+BMT group, the incidence was 0%. Serological findings in the MPSL+BMT group were almost normalized. VEGF and TUNEL staining were reduced in the MPSL+BMT group compared with all other groups. There were significantly fewer BMCs in G1 phase from the MPSL+BMT group than the other groups, while uptake of [(3)H]-thymidine was significantly increased. CONCLUSION: Direct injection of autologous BMCs into femurs prevents corticosteroid-induced ON following treatment with high-dose, short-term steroids.

Full-sized RanBPM cDNA encodes a protein possessing a long stretch of proline and glutamine within the N-terminal region, comprising a large protein complex.

Previously isolated RanBPM, a Ran-binding protein in the microtubule-organizing center, which had been thought to play a role in Ran-stimulated microtubule assembly, turned out to be a truncated protein. To clarify the function of RanBPM, we cloned the full-sized RanBPM cDNA that encodes a 90 kDa protein, compared to the previously isolated cDNA that encoded a 55 kDa protein. The newly cloned 5' coding region contains a great number of cytidine and guanidine nucleotides, like the CpG island. Thus, full-sized RanBPM cDNA encodes a long stretch of proline and glutamine residues in the N-terminal region. It comprises a protein complex of more than 670 kDa. Ran was detected in this complex when RanBPM and Ran were both ectopically expressed. New antibodies to RanBPM were prepared against three different regions of RanBPM. All of them detected a 90 kDa protein that is predominantly localized both in the nucleus and in the cytoplasmic region surrounding the centrosome, but none of them stained the centrosome. In this context, our previous notion that RanBPM is a centrosomal protein should be discarded. RanBPM is well conserved in the animal kingdom. It may play an important role in uncovering Ran-dependent nuclear events.

Functional identification of an Arabidopsis snf4 ortholog by screening for heterologous multicopy suppressors of snf4 deficiency in yeast.

Yeast Snf4 is a prototype of activating gamma-subunits of conserved Snf1/AMPK-related protein kinases (SnRKs) controlling glucose and stress signaling in eukaryotes. The catalytic subunits of Arabidopsis SnRKs, AKIN10 and AKIN11, interact with Snf4 and suppress the snf1 and snf4 mutations in yeast. By expression of an Arabidopsis cDNA library in yeast, heterologous multicopy snf4 suppressors were isolated. In addition to AKIN10 and AKIN11, the deficiency of yeast snf4 mutant to grown on non-fermentable carbon source was suppressed by Arabidopsis Myb30, CAAT-binding factor Hap3b, casein kinase I, zinc-finger factors AZF2 and ZAT10, as well as orthologs of hexose/UDP-hexose transporters, calmodulin, SMC1-cohesin and Snf4. Here we describe the characterization of AtSNF4, a functional Arabidopsis Snf4 ortholog, that interacts with yeast Snf1 and specifically binds to the C-terminal regulatory domain of Arabidopsis SnRKs AKIN10 and AKIN11.

Effects of docosahexaenoic and arachidonic acids on the synthesis and distribution of aminophospholipids during neuronal differentiation of PC12 cells.

We have shown previously that docosahexaenoic acid (DHA) promotes and arachidonic acid (AA) suppresses neurite outgrowth of PC12 cells induced by nerve growth factor (NGF) and that incorporation of [3H]ethanolamine into phosphatidylethanolamine (PE) is suppressed in PC12 cells by AA while DHA has no effect. In the present study, the effects of these fatty acids on PE synthesis via decarboxylation of phosphatidylserine (PS), another pathway of PE synthesis, and distribution of aminophospholipids were examined. Incorporation of [3H]serine into PS and PE was elevated in the course of NGF-induced differentiation and was further stimulated significantly by DHA, but not by AA. [3H]Ethanolamine uptake by PC12 cells was significantly suppressed by AA but not by DHA while these fatty acids did not affect [3H]serine uptake, indicating that the suppression by AA of [3H]ethanolamine incorporation into phosphatidylethanolamine is attributable, at least in part, to a reduction in [3H]ethanolamine uptake. The distribution of PE in the outer leaflet of plasma membrane decreased during differentiation, which is known to be accompanied by an increase in the surface area of plasma membrane. Supplementation of PC12 cells with DHA or AA did not affect the distribution of aminophospholipids. Thus, DHA and AA affected aminophospholipid synthesis and neurite outgrowth differently, but not the transport and distribution of aminophospholipids, while the PE concentration in the outer leaflet of the plasma membrane decreased in association with morphological changes in PC12 cells induced by NGF.

[Functional brain mapping in motor task and somatosensory stimulation using echo planar MRI].

Functional brain mapping was performed with a 1.5T clinical MRI apparatus. Single shot gradient echo echo-planar imaging (EPI) sequence was employed. Normal volunteers were studied with the task of grasping hand or opposition of fingers at the frequency of 3 Hz, median nerve electro-stimulation, pure somatosensory stimulation by roller for acupuncture. Apparent signal increase was observed at contralateral sensorimotor cortex with motor task. Signal changes delayed about 5 seconds compared with the start and the cessation of the task, which may suggest that regional changes of CBF and blood oxygen level in capillary and/or in venule lag behind electrical excitation. It was hard to detect the activated area with median nerve electro-stimulation. On the other hand, roller stimulation provoked distinct activated areas at contralateral sensorimotor cortex. The activated areas caused by the roller stimulation and the motor task coincided entirely, which suggests the possibility of the intermixed localization of primary areas of motor and somatosensory. It was also clearly demonstrated that the activated area was broader with quick (3 Hz) and complicated motor task (finger opposition) than with slow (1Hz) and simple motor task (hand grasping).

Non-invasive measurement of brain activity using functional MRI: toward the study of brain response to acupuncture stimulation.

We studied functional MRI in 15 male and 13 female normal volunteers on a clinical MRI system using gradient echo sequence. During the experiments, brain activation was induced by grasping the unilateral hand once or twice a second for motor tasks. A localized increase of MRI signal in the contralateral motor cortex was observed in 17 out of 21 cases (81%) under right hand motor task and 11 out of 21 cases (52%) under left hand motor task. The application of this method may be useful to evaluate brain response to acupuncture.

Expressed sequence tags from cultured cells of rice (Oryza sativa L.) under stressed conditions: analysis of transcripts of genes engaged in ATP-generating pathways.

Large-scale sequencing of randomly selected cDNA clones was used to isolate numerous genes in rice (Oryza sativa L.). Total RNA used for cDNA synthesis was prepared from suspension-cultured cells of rice grown under stressed conditions, such as in saline or nitrogen-starvation conditions. A total of 780 cDNA clones were partially sequenced and about 15% could be identified as putative genes. In the library constructed under saline conditions, we identified several genes associated with signal transduction, such as protein kinase and small GTP-binding protein genes. Many stress-related genes were isolated from both the saline and nitrogen-starvation libraries. These results indicate that stress treatment of suspension-cultured cells makes it possible to efficiently isolate various types of plant genes. To examine the usefulness of such tagged cDNAs for the study of gene expression in a specific metabolic pathway, we analyzed mRNA levels of genes engaged in the ATP-generating pathways in cultured cells of rice under different stresses, such as 20% sucrose, salt stress, cold stress and nitrogen-starvation stress. The results suggest that the coordinated induction of several genes in key steps under stressed conditions may be essential for activation of the entire energy-producing pathway to maintain homeostasis in rice cells. Expressed sequence tags identified by random cDNA sequencing provide the opportunity to generate a transcript map of rice genes.

Improvement of ischemic myocardial dysfunction by nisoldipine in relation to its coronary vasodilating action.

We examined the cardioprotective effect of nisoldipine against myocardial dysfunction during ischemia and reperfusion in comparison with those of diltiazem and nifedipine in rabbit hearts perfused at constant pressure. These calcium antagonists were administered to the hearts before 60 min of ischemia. They inhibited the increase of end-diastolic pressure during ischemia in a dose-dependent manner. Diltiazem at 1.0 microM, nifedipine at 3.0 microM and nisoldipine at 0.01 microM produced the maximal cardioprotective effect. Nisoldipine had a beneficial effect with less negative inotropic effect than those of diltiazem and nifedipine and it produced a significant increase of coronary flow during reperfusion. When the vascular component was eliminated under constant flow perfusion, nisoldipine also showed the cardioprotective effect. Nisoldipine did not produce any beneficial effect without the inhibition of the increase in end-diastolic pressure during ischemia nor did it do so without the increase of reperfusion flow. Therefore, the nisoldipine-increased coronary flow during reperfusion as well as the inhibition of ischemic contracture by nisoldipine seems to play a crucial role in improving the myocardial dysfunction of ischemic-reperfused hearts.

Purification and characterization of extracellular matrix-degrading metalloproteinase, matrin (pump-1), secreted from human rectal carcinoma cell line.

A metalloproteinase with Mr 29,000 was purified to homogeneity as a latent proenzyme from the conditioned medium of a human rectal carcinoma cell line CaR-1. This enzyme hydrolyzed casein more potently than gelatin embedded in polyacrylamide gels in zymography assay. Calcium ion was essential for the activity. It exerted the maximum activity at pH 7-9. Its activity was stimulated by organomercurials, such as p-amino-phenyl mercuric acetate and p-chloromercuric benzoic acid, and was inhibited by 1,10-phenanthroline but was hardly affected by diisopropyl fluorophosphate and pepstatin. When the purified proenzyme was activated by the organomercurials, it effectively hydrolyzed fibronectin, laminin, type IV basement membrane collagen, and several types of gelatins but not interstitial type I and III collagens. The treatment of the purified proenzyme with p-aminophenyl mercuric acetate or trypsin formed an active peptide with Mr 20,000. The structural analysis indicated that it was most likely identical to putative metalloproteinase-1, the complementary DNA of which had been cloned from human tumor mRNAs capable of hybridizing to a rat transin complementary DNA. Based on the fact that this enzyme is secreted extracellularly and degrades the matrix proteins, we propose the name "matrin" for this newly identified enzyme.

Red blood cell aluminum in patients with renal failure and effect of desferrioxamine infusion.

Red blood cell (RBC) aluminum (Al) in patients with renal failure on different treatments was studied. Nondialyzed renal failure patients had high levels of RBC Al, but low serum Al levels. However, their RBC Al levels were lower than those of patients on hemodialysis (HD) and continuous ambulatory peritoneal dialysis. In addition, HD patients who were not given Al-containing medications showed high levels of RBC Al, which suggests that there may be a source of Al other than medications. When desferrioxamine (DFO) was administered to these HD patients, the changes in RBC Al levels after DFO infusion were independent of those in serum Al levels and blood hemoglobin levels. In an in vitro study, RBC Al was removed using an ultrafiltration membrane, which showed that RBC Al exists in a bound form. These results suggest that Al accumulates in RBCs of renal failure patients independently of serum Al levels, and that the improvement of anemia by DFO may not be due to the direct removal of RBC Al.

Effect of shosaikoto, daisaikoto and sannoshashinto (traditional Japanese and Chinese medicines) on experimental hyperlipidemia in rats.

Effect of Sannoshashinto, Shosaikoto and Diasaikoto, Japanese and Chinese traditional medicinal mixtures (kampohozai), on cholesterol-induced hypercholesterolemia, aging-induced hyperlipidemia and cholesterol turnover were studied in rats. Sannoshashinto, Shosaikoto and Daisaikoto reduced the hypercholesterolemia induced by a high cholesterol diet and Sannoshashinto and Daisaikoto improved the atherogenetic index. Liver total cholesterol as increased by a high cholesterol diet was reduced by all three kampohozai. Furthermore, the increases of serum and liver triglyceride were also inhibited. In an experiment using untreated aging rats, both serum total cholesterol and serum triglyceride levels were increased. The aging-induced increases of serum total cholesterol were inhibited by Sannoshashinto and Daisaikoto and the increases of serum triglyceride were reduced by all three kampohozai. These drugs showed no effect on cholesterol biosynthesis in liver. Sannoshashinto, however, appeared to accelerate the disappearance of cholesterol from blood, while Daisaikoto inhibited the cholesterol absorption from the intestine.

Effects of certain herbal medicines on the biotransformation of arachidonic acid: a new pharmacological testing method using serum.

Two in vitro experimental systems were compared to evaluate the pharmacological effects of some herbal medicines on the biotransformation of arachidonic acid (AA) using the microsomal fraction of sheep vesicular glands as an enzyme source. The first system involved the addition of serum obtained from rats treated orally with the herbal medicines, while the second system involved the direct addition of herbal medicine extracts to the enzyme medium. Both systems were performed in parallel. Indomethacin, used as a reference drug, inhibited AA biotransformation in a dose-dependent manner in both experimental systems. The serum of rats orally pretreated for 1 h with Coptis japonica rhizome and Paeonia lactiflora root also inhibited AA biotransformation. Direct addition of hot water extracts of Rheum officinale rhizome, Scutellaria baicalensis root, Paeonia moutan bark and Zingiber officinale rhizome also inhibited AA biotransformation, while the extracts of Coptis japonica rhizome and Paeonia lactiflora root showed no effects.

Transforming growth factor activity in human colostrum.

When human milk was examined for the presence of transforming growth factor (TGF) activity, high levels of the activity were found in milk collected in the early days after delivery. Fractionation of an acid-ethanol extract of colostrum by Bio-Gel P-60 column chromatography revealed that the activity was found in two molecular weight ranges; over 45,000 and from 10,000 to 20,000 daltons. The activity of the milk TGF did not compete with epidermal growth factor (EGF) for EGF receptor and was potentiated by the addition of EGF when assayed using normal rat kidney (NRK) cells.

Short-term cultivation of human mammary tumors and normal mammary glands in medium containing human colostrum milk.

A short-term cultivation of human mammary tumors and normal mammary glands was attempted in order to establish a reproducible method for their cultivation. Epithelial cells could be cultivated consistently by the use of collagenase for tissue dissociation and the addition of insulin, human colostrum milk and cholera toxin to the culture medium. Human colostrum milk seemed to be a good additive for the growth of mammary epithelial cells but not for that of fibroblastic cells.

Properties of cell lots suitable for focus assay in the chemical transformation of Syrian hamster cells in culture.

Various lots of cells obtained from Syrian hamster tissues were examined to determine their suitability for focus assay in chemical transformation in culture. Only a few lots of cells showed growth with sparse cell density during cultivation for 3 weeks without subcultivation, and not all lots of cells produced morphologically transformed foci after treatment with a carcinogen. Further, responsiveness to a tumor promotor, 12-O-tetradecanoly phorbol-13-acetate (TPA), differed among different cell lots; cell lots which induced abundant growth consisting of small spindle-shaped multilayered cells upon treatment with TPA corresponded to those in which carcinogen treatment induced transformed colonies. When TPA was applied in transformation experiments, the morphologically transformed foci grew larger in cultures maintained in the TPA medium than in cultures kept in the TPA-free medium. We suggest that cell lots which show relatively sparse cell density at confluent culture and which show abundant growth consisting of small multilayered cells upon induction with TPA are suitable for transformation assay.