The effects of amphiphilic cationic drugs and inorganic cations on the activity of phosphatidate phosphohydrolase.

1. Phosphatidate phosphohydrolase from the particle-free supernatant of rat liver was assayed by using emulsions of phosphatidate as substrate. 2. The inhibition of the phosphohydrolase by chlorpromazine was of a competitive type with respect to phosphatidate. The potency of various amphiphilic cationic drugs as inhibitors of this reaction was related to their partition coefficients into a phosphatidate emulsion. 3. The effect of chlorpromazine on the phosphohydrolase activity was complementary rather than antagonistic towards Mg2+. Chlorpromazine stimulated the phosphohydrolase activity in the absence of added Mg2+ and was able to replace the requirement for Mg2+. However, at optimum concentrations of Mg2+, chlorpromazine inhibited the reaction, as did Ca2+. The phosphohydrolase activity was also stimulated by Co2+ and to a lesser extent by Mn2+, Fe2+, Fe3+, Ca2+, spermine and spermidine when Mg2+ was not added to the assays. 4. It is concluded that the inhibition of phosphatidate phosphohydrolase by amphiphilic cations can largely be explained by the interaction of these compounds with phosphatidate, which changes the physical properties of the lipid, making it less available for conversion into diacylglycerol. 5. The implications of these results to the effects of amphiphilic cations in redirecting glycerolipid synthesis at the level of phosphatidate are discussed.     

苜蓿核糖体基因物理定位及染色体荧光分带

利用核糖体基因为探针对,二倍体和四倍体苜蓿(Medicago sativa)进行原位杂交,结果表明,45s在四倍体、二倍体种中总是以单位点位于核仁组织区,5s则有2～3个位点;以二倍体种的基因组DNA为探针的原位杂交表明,蓝花苜蓿(M.coerulea)和黄花苜蓿(M.falcata)均能与四倍体染色体进行杂交,仅杂交信号强弱的染色体数目有差别;荧光染料DAPI使苜蓿的染色体显示带纹,蓝花苜蓿的DAPI带与C-带基本一致.文章对四倍体苜蓿的可能来源进行了讨论.     

Pyramiding Mn-superoxide dismutase transgenes to improve persistence and biomass production in alfalfa

Expression of individual superoxide dismutase (SOD) transgenes improves environmental stress tolerance and biomass production in alfalfa (Medicago sativa L.). The objective of this study was to test the hypothesis that synergy exists between transgenic SOD stress-tolerance mechanisms, specifically that the simultaneous expression of two SOD transgenes confers greater benefit than the expression of a single SOD transgene. The hypothesis was tested through an evaluation of an F(1) family generated through a sexual cross of a hemizygous Mit-MnSOD plant and a hemizygous Chl-MnSOD-transgenic alfalfa plant which had previously been screened in field trials for improved persistence. Southern analyses revealed that the parents each had single insertion regions of the MnSOD cDNA and the inheritance followed the expected Mendelian ratios. Native PAGE gels and enzyme inhibition assays revealed the activity of the transgenic MnSOD isozymes. F(1) progeny containing either the Mit-MnSOD or the Chl-MnSOD transgene had significantly higher storage organ (crown+root) biomass compared to non-transgenic siblings. The joint expression of the transgenes resulted in a numerical increase in total SOD activity. However, F(1) progeny containing both transgenes had lower shoot and storage organ biomass compared to siblings having only one or the other transgene, a result that did not support the authors' hypothesis. It was postulated that a promoter with lower expression than 35S may be necessary if closely related transgenes are to be pyramided in the same plant.     

Experience in the application of Java Technologies in telemedicine

Java language has been demonstrated to be an effective tool in supporting medical image viewing in Russia. This evaluation was completed by obtaining a maximum of 20 images, depending on the client's computer workstation from one patient using a commercially available computer tomography (CT) scanner. The images were compared against standard CT images that were viewed at the site of capture. There was no appreciable difference. The client side is a lightweight component that provides an intuitive interface for end users. Each image is loaded in its own thread and the user can begin work after the first image has been loaded. This feature is especially useful on slow connection speed, 9.6 Kbps for example. The server side, which is implemented by the Java Servlet Engine works more effective than common gateway interface (CGI) programs do. Advantages of the Java Technology place this program on the next level of application development. This paper presents a unique application of Java in telemedicine.     

ACUTE EFFECTS OF MOVEMENT VELOCITY ON BLOOD LACTATE AND GROWTH HORMONE RESPONSES AFTER ECCENTRIC BENCH PRESS EXERCISE IN RESISTANCE-TRAINED MEN

This study aimed to compare the effects of different velocities of eccentric muscle actions on acute blood lactate and serum growth hormone (GH) concentrations following free weight bench press exercises performed by resistance-trained men. Sixteen healthy men were divided into two groups: slow eccentric velocity (SEV; n = 8) and fast eccentric velocity (FEV; n = 8). Both groups performed four sets of eight eccentric repetitions at an intensity of 70% of their one repetition maximum eccentric (1RMecc) test, with 2-minute rest intervals between sets. The eccentric velocity was controlled to 3 seconds per range of motion for SEV and 0.5 seconds for the FEV group. There was a significant difference (P < 0.001) in the kinetics of blood lactate removal (at 3, 6, 9, 15, and 20 min) and higher mean values for peak blood lactate (P = 0.001) for the SEV group (9.1 ± 0.5 mM) compared to the FEV group (6.1 ± 0.4 mM). Additionally, serum GH concentrations were significantly higher (P < 0.001) at 15 minutes after bench press exercise in the SEV group (1.7 ± 0.6 ng · mL⁻¹) relative to the FEV group (0.1 ± 0.0 ng · mL⁻¹). In conclusion, the velocity of eccentric muscle action influences acute responses following bench press exercises performed by resistance-trained men using a slow velocity resulting in a greater metabolic stress and hormone response.     

Comparison of dot chromosome sequences from D. melanogaster and D. virilis reveals an enrichment of DNA transposon sequences in heterochromatic domains

Background

Chromosome four of Drosophila melanogaster, known as the dot chromosome, is largely heterochromatic, as shown by immunofluorescent staining with antibodies to heterochromatin protein 1 (HP1) and histone H3K9me. In contrast, the absence of HP1 and H3K9me from the dot chromosome in D. virilis suggests that this region is euchromatic. D. virilis diverged from D. melanogaster 40 to 60 million years ago.

Results

Here we describe finished sequencing and analysis of 11 fosmids hybridizing to the dot chromosome of D. virilis (372,650 base-pairs) and seven fosmids from major euchromatic chromosome arms (273,110 base-pairs). Most genes from the dot chromosome of D. melanogaster remain on the dot chromosome in D. virilis, but many inversions have occurred. The dot chromosomes of both species are similar to the major chromosome arms in gene density and coding density, but the dot chromosome genes of both species have larger introns. The D. virilis dot chromosome fosmids have a high repeat density (22.8%), similar to homologous regions of D. melanogaster (26.5%). There are, however, major differences in the representation of repetitive elements. Remnants of DNA transposons make up only 6.3% of the D. virilis dot chromosome fosmids, but 18.4% of the homologous regions from D. melanogaster; DINE-1 and 1360 elements are particularly enriched in D. melanogaster. Euchromatic domains on the major chromosomes in both species have very few DNA transposons (less than 0.4 %).

Conclusion

Combining these results with recent findings about RNAi, we suggest that specific repetitive elements, as well as density, play a role in determining higher-order chromatin packaging.     

Oral curcumin supplementation improves fine motor function in the middle-aged rhesus monkey

Aged individuals experience decreased fine motor function of the hand and digits, which could result, in part, from the chronic, systemic state of inflammation that occurs with aging. Recent research for treating age-related inflammation has focused on the effects of nutraceuticals that have anti-inflammatory properties. One particular dietary polyphenol, curcumin, the principal curcuminoid of the spice turmeric, has been shown to have significant anti-inflammatory effects and there is mounting evidence that curcumin may serve to reduce systemic inflammation. Therefore, it could be useful for alleviating age-related impairments in fine motor function. To test this hypothesis we assessed the efficacy of a dietary intervention with a commercially available optimized curcumin to ameliorate or delay the effects of aging on fine motor function of the hand of rhesus monkeys. We administered oral daily doses of curcumin or a control vehicle to 11 monkeys over a 14- to 18-month period in which they completed two rounds of fine motor function testing. The monkeys receiving curcumin were significantly faster at retrieving a food reward by round 2 of testing than monkeys receiving a control vehicle. Further, the monkeys receiving curcumin demonstrated a greater degree of improvement in performance on our fine motor task by round 2 of testing than monkeys receiving a control vehicle. These findings reveal that fine motor function of the hand and digits is improved in middle-aged monkeys receiving chronic daily administration of curcumin.     

A method for assessing recovery of fine motor function of the hand in a rhesus monkey model of cortical injury: an adaptation of the Fugl–Meyer Scale and Eshkol–Wachman Movement Notation

Motor dysfunction of the upper extremity can result from stroke, cortical injury and neurological diseases and causes significant disruption of activities of daily living. While some spontaneous recovery in terms of compensatory movements does occur after injury to cortical motor areas, full recovery is rare. The distinction between complete recovery and compensatory recovery is important as the development of compensatory movements in the upper extremity may not translate into full functional use in human patients. However, current animal models of stroke do not distinguish full recovery from compensatory recovery. We have developed a Non-Human Primate Grasp Assessment Scale (GRAS) to quantify the precise recovery of composite movement, individual digit action, and finger-thumb pinch in our rhesus monkey model of cortical injury. To date, we have applied this GRAS scale to assess the recovery of fine motor function of the hand in young control and cell-therapy treated monkeys with cortical injury confined to the hand representation in the dominant primary motor cortex. We have demonstrated that with this scale we can detect and quantify significant impairments in fine motor function of the hand, the development of compensatory function during recovery and finally a return to full fine motor function of the hand in monkeys treated with a cell therapy.