Spread of HTLV-I between lymphocytes by virus-induced polarization of the cytoskeleton

Cell contact is required for efficient transmission of human T cell leukemia virus- type 1 (HTLV-I) between cells and between individuals, because naturally infected lymphocytes produce virtually no cell-free infectious HTLV-I particles. However, the mechanism of cell-to-cell spread of HTLV-I is not understood. We show here that cell contact rapidly induces polarization of the cytoskeleton of the infected cell to the cell-cell junction. HTLV-I core (Gag protein) complexes and the HTLV-I genome accumulate at the cell-cell junction and are then transferred to the uninfected cell. Other lymphotropic viruses, such as HIV-1, may similarly subvert normal T cell physiology to allow efficient propagation between cells.     

Hf-W chronometry of lunar metals and the age and early differentiation of the Moon

The use of hafnium-tungsten chronometry to date the Moon is hampered by cosmogenic tungsten-182 production mainly by neutron capture of tantalum-181 at the lunar surface. We report tungsten isotope data for lunar metals, which contain no 181Ta-derived cosmogenic 182W. The data reveal differences in indigenous 182W/184W of lunar mantle reservoirs, indicating crystallization of the lunar magma ocean 4.527 +/- 0.010 billion years ago. This age is consistent with the giant impact hypothesis and defines the completion of the major stage of Earth's accretion.     

Ratios of Nutrients in Lowland Rice Grown on Two Iron Toxic Soils in Nigeria

ABSTRACT

Iron (Fe) toxicity is a widespread nutritional soil constraint affecting rice production in the wetland soils of West Africa. Critical levels of total iron in plant causing toxicity is difficult to determine as different rice cultivars respond to excessive Fe^{2 +} in various ways in what is called “bronzing” or “yellowing” symptoms (VBS). An investigation was conducted to evaluate the relationship between plant growth and nutrient ratios at four iron levels (1000, 3000, 4000 μ g L^?1) and control. This involved two rice cultivars (‘ITA 212’ and ‘Suakoko 8’), and two soil types (Aeric Fluvaquent and Aeric Tropaquept). The experimental design was a 2 × 2 × 4 factorial in a completely randomized fashion with four replications. The results showed that nutrient ratios [phosphorus (P)/Fe, potassium (K)/Fe, calcium (Ca)/Fe, magnesium (Mg)/Fe, and manganese (Mn)/Fe), Fe content, and Fe uptake vary widely with the iron levels as well as with the age of the cultivars. The iron toxicity scores expressed as VBS increased with increasing Fe^{2 +} in the soils, resulting in simultaneous reduction of the following variables: plant height, tiller numbers/pot, relationships grain yield (GY) and dry matter yield (DMY). There were no significant difference between nutrient ratios, Fe contents, Fe uptake, the GY and DMY of both rice cultivars on both soil types. Multiple stepwise regression analysis showed that Fe uptake and Fe contents contributed 42% and 17% respectively to the variation in the grain yield of ‘ITA 212’ on Aeric Tropaquept. On both soil types and cultivars, Fe uptake and Fe content contributed between 26 and 68% to the variation in the DMY, while the nutrient ratios (P/Fe, K/Fe, Ca/Fe, and Mn/Fe) contributed between 3% and 13% DMY. Thus, it could be concluded that iron toxicity in rice is more a function of a single nutrient (Fe) rather than nutrient ratios.     

Current analytical techniques in soil biogeochemistry

Soil biogeochemistry is developed through studying the behavior of atoms in soils and landscapes and their compounds: molecules, organic-mineral complexes, and crystal structures, as well as biota. Biogeochemists and soil scientists developed new experimental methods as a result of these studies. The best results were shown by electron microscopy and spectral methods-nuclear gamma resonance, nuclear magnetic resonance (NMR), and synchrotron radiation based X-ray adsorption spectroscopy. They allowed for the acquisition of new evidence on the role of biota in the geochemistry of many chemical elements in the composition of both the mineral and organic parts of the soil. The latest key results of these investigations from around the world are given.     

GENETICALLY MODIFIED AND CONVENTIONAL DRY BEAN GENOTYPE RESPONSES TO SOIL FERTILITY

Dry bean is important pulse for the diet of South American population and results related to comparison of genetically modified and conventional dry bean genotypes to soil fertility are limited. A greenhouse experiment was conducted to compare genetically modified and conventional dry bean genotypes to soil fertility. Genotypes evaluated were Olathe Pinto, Olathe 5.1 (genetically modified), BRS Pontal, BRS Pontal 5.1 (genetically modified), Pérola and Pérola 5.1 (genetically modified). Fertility levels were 1 g fertilizer (5-30-15) kg^?1 soil (low fertility level) and 2 g fertilizer (5-30-15) per kg soil (high fertility level). These fertility levels were designated as low and high, respectively. Grain yield, number of pods per plants, and seed per pod were significantly increased with the increase in soil fertility. Shoot dry weight, seed per pod, and 100 seed weight were also significantly influenced by genotype treatment. Fertility X genotypes interaction was significant for maximum root length and root dry weight, indicating genotypes responded differently at two fertility levels in relations to these two traits. Shoot dry weight, number of pods per plant, and grain harvest index had significant association with grain yield, indicating that increase in these three traits grain yield can be increased. Grain yield efficiency index (GYEI) was having significant linear association with grain yield. Hence, on the basis of GYEI, genotypes were classified as efficient (E), moderately efficient (ME), and inefficient in nutrient use. Three conventional genotypes (Olathe Pinto, BRS Pontal and Pérola) and one genetically modified genotype (Olathe Pinto 5.1) were classified as moderately efficient and two genetically modified genotypes (Pérola 5.1 and BRS Pontal 5.1) were classified as efficient. None of the genotypes fall into the inefficient group.     

砖质固定化硝化细菌对氨气及铵态氮的转化效果

以普通建筑用砖为吸附载体对硝化细菌固定化,研究固定化硝化细菌(INB)对NH3及NH4+-N的转化效果。结果表明,INB与NH3接触6 h后,NH3的转化率为60.2%;INB对(NH4)2SO4溶液中的NH4+-N有很强的转化能力,在初始质量浓度为5.0、20.0 g/L的(NH4)2SO4溶液中,NH4+-N平均转化率分别为81.7%、86.6%;INB在37℃硝化细菌富集培养液中培养12 h,对NH3平均转化率提高27.5%。说明,普通建筑用砖可以作为硝化细菌的固定载体,用该载体制备的INB对NH3和NH4+-N均有较强的转化能力,可以通过加入硝化细菌培养液进行再培养提高砖质INB对NH3转化率,实现INB重复使用。     

Evaluation of Pine Bark or Pine Bark with Goat Manure or Sewage Sludge Cocomposts As Growing Media for Vegetable Seedlings

The suitability as growing media of composts made from pine bark or pine bark cocomposted with goat manure or sewage sludge and either inoculated or not inoculated with effective microorganisms, was evaluated under greenhouse conditions with and without fertilization using cabbage as the test crop. The treatments were replicated three times and arranged in a randomized complete block design in a fibre glass covered greenhouse. Cabbage seedlings were grown in cavity trays for five weeks, after which plants were harvested and fresh and dry weights determined. Samples were also analyzed for N, P, K and selected heavy metal concentrations. Results revealed that pine bark-goat manure cocomposts supported good seedling growth and could thus be good substitutes for pine bark alone as a growing medium where goat manure or similar manures are available. The results also showed that despite the superior nutritional value of these alternative growing media, nutrient supplementation may still be necessary where seedlings are kept in the nursery for extended periods due to nutrient exhaustion through plant uptake and leaching. Pine bark-sewage sludge compost also had positive effects on seedling growth but could only be recommended as a growing medium for nonfood plants because its composting did not reach the thermophillic temperatures necessary for adequate pathogen kill. Inoculation with effective microorganisms improved seedling growth in sewage sludge and goat manure based composts but the mechanisms involved remain to be established.     

Traumatic luxation of the cubital joint (elbow) in dogs: 44 cases (1978-1988).

The medical records from 44 dogs with traumatic luxation of the cubital joint were reviewed. Closed reduction was performed in 35 dogs, and open reduction in 9 dogs. Excellent or good results were achieved in 31 of 35 dogs (88.6%) treated by closed reduction and in 5 of 9 dogs (55.6%) treated by open reduction. Collateral ligament repair, performed in 5 dogs, did not appear to affect the prognosis. Factors such as body weight and type and duration of external coaptation also did not appear to influence the outcome. Increased dysfunction associated with open reduction most likely was caused by the chronic nature of the dislocation, iatrogenic damage to the articular cartilage during reduction, or both. A good prognosis for return to normal function with minimal gait abnormality can be expected in most cases of traumatic luxation of the cubital joint treated by early closed reduction.     

罗非鱼湖病毒病传入风险分析

为评估罗非鱼湖病毒（tilapia lake virus,TiLV）跨境传入风险,按照OIE传入风险评估框架,从危害识别、风险评估及风险管理3个方面,开展了TiLV跨境传入风险分析,并提出了相应的风险控制措施。分析认为：活的敏感鱼类（包括亲鱼、鱼卵和鱼苗）,用做鲜活饵料的鱼类（野杂鱼）及冰冻和冰鲜的敏感鱼类（包括去除内脏的鱼肉）TiLV传入风险较高,而敏感鱼加工类产品、非敏感鱼类（包括活的和其他形式的产品）及运输活鱼的水、包装、运输工具和用具等传入风险较低。建议不从疫区进口高风险产品,对于低风险产品可以自由贸易,而对运输活鱼的水、包装、运输工具和用具等要进行强制常规消毒。     

Schirmer Tear Test in Clinically Normal Asian Elephants

Veterinary Research Communications -