Evaluation of monoammonium phosphate and bacterial strains to increase tree growth and fruit yield in apple replant problem soil

The long-term effects of biological agents alone and in combination with monoammonium phosphate on tree growth and fruit production of apple trees planted on apple replant soil was studied for five years. Application of monoammonium phosphate (MAP) in the year of planting increased shoot growth, cross-sectional trunk area and fruit yield of McIntosh on M.26 rootstock for the first two years. The application of bacterial agents alone were not effective in increasing young tree growth except BACT-1 in 1987. None of the bacterial agents increased fruit yield when applied alone. The addition of certain bacterial agents to MAP application increased young tree growth in various years. The combination of bacterial agent B-10 and MAP reduced young tree growth and yield compared with the MAP treatment alone. These results suggest that the application of MAP alone may be sufficient to alleviate the replant problem and the addition of BACT-1, EBW-4 or B8 bacterial agents to this treatment may be beneficial to increase tree growth in some years. Contribution number 822. Contribution number 822.     

Trace elements in hair of blackfoot disease

Blackfoot disease is a peripheral vascular disease resulting in gangrene of the lower extremities. Though extensive epidemiological study has implicated that high arsenic content in artesian well water of the endemic area, bears some important connection with the disease, the etiology of the disease is still unknown. In this study, attention is paid to multielement determination in order to find out whether the trace elements in hair of Blackfoot disease patients are different from those of the controls. Experimental results indicate that the concentrations of As and Se in hair of patients are significantly higher than those of the controls, but Ca and Zn are significantly lower than those of the controls. The possible connection of these elements with the etiology of the disease is discussed.     

Induction and accumulation of phytoalexins in cowpea roots infected with a mycorrhizal fungusGlomus fasciculatum and their resistance toFusarium wilt disease

The interaction of a vesicular-arbuscular mycorrhizal fungusGlomus fasciculatum with a wilt-causing soil borne pathogen,Fusarium oxysporum, was studied in cowpea (Vigna unguiculata). It was found that pre-establishment by vesicular-arbuscular mycorrhizal fungus reduced the colonization of the pathogen and the severity of the disease, as determined by reduction in vascular discolouration index. In mycorrhizal plants, the production of phytoalexin compounds was always higher than in the nonmycorrhizal plants. There appeared to be a direct correlation between the concentration of the phytoalexins and the degree of mycorrhizal association. Three different compounds withR _f values of 0.23 (I), 0.17 (II) and 0.11 (III) were obtained from mycorrhizal plants. Similar compounds were also found to be induced by an abiotic elicitor CuSO₄. The first compound was identified as an isoflavonoid, daidzein and the other two remain to be identified. These compounds were checked for their antifungal activityin vitro. The germination of conidial spores ofFusarium oxysporum was strongly inhibited by the compound III than the other two. It is argued that the production of phytoalexin compounds in mycorrhizal plant could be one of the mechanisms imparting tolerance of the plants to wilt disease.     

The dieback ofZostera marina in the 1930's in the Waddensea; An eye-witness account by A. van der Werff

In the archives of the State Institute of Fisheries Research a handwritten report of A. van der Werff on the wasting disease ofZostera marina L. in the Waddensea in 1932 and 1933 is kept. It contains an eye-witness account of the decline of the eelgrass beds. In 1932 the first attack of the disease took place in May and caused heavy devastation. Regeneration started soon, but a second attack at the end of August seemed to destroy the beds definitively. The next year was a year of struggle for the few poorly developed surviving plants. In 1938 the last surviving specimens were seen in the sublittoral.     

Bulb canker of garlic caused byEmbellisia allii,newly found in Japan

Bulb canker of garlic caused byEmbellisia allii was newly detected in Japan. Symptoms of the disease are described and the morphological characteristics of the causal fungus are illustrated and described.     

Neurotrophic factor therapy for nervous system degenerative diseases

The ability of neurotrophic factors to regulate developmental neuronal survival and adult nervous system planticity suggests the use of these molecuales to treat neurodegeneration associated with human diseases. Solid rationales exist for the use of NGF and neurotrophin-3 in the treatment of neuropathies of the peripheral sensory system, insulin-like growth factor and ciliary neurotrophic factor in motor neuron atrophy, and NGF in Alzheimer's disease. Growth factors have been identified for neurons affected in Parkinson's disease, Huntington's disease, and acute brain and spinal cord injury. Various strategies are actively pursued to deliver neurotrophic factors to the brain, and develop therapeutically useful molecules that mimic neurotrophic factor actions or stimulate their production or receptor mechanisms. 1994 John Wiley & Sons, Inc.     

降钙素基因相关肽的研究进展

降钙素基因相关肽（ＣＧＲＰ）是由３７个氨基酸残基构成的生物活性多肽,与降钙素（ＣＴ）源子一个共同的基因。ＣＧＲＰ分布广泛,具有很强的血管扩张、降低血压以及心肌正性肌力作用等,并参与心血管系统稳态的调节。目前,ＣＧＲＰ已能人工合成,将为某些心血管疾病如高血压、心肌缺血、痉挛性或闭塞性周围血管疾病等的治疗提供一条崭新的途径。     

重组BCG口服免疫诱导的细胞和体液免疫应答

重组ＢＣＧ口服免疫诱导的细胞和体液免疫应答最近研究证明,外源基因能在牛分枝杆菌ＢＣＧ中表达,用这些重组分枝杆菌免疫小鼠可诱导抗外来蛋白的细胞和抗体免疫应答。近年来的许多研究也证实了肠道和呼吸道粘膜淋巴系统在防御感染方面的贡献,因此,迫切需要能够刺激粘...     

Striatal L-DOPA Decarboxylase Activity in Parkinson's Disease In Vivo: Implications for the Regulation of Dopamine Synthesis

Abstract: L-DOPA is a large neutral amino acid subject to transport out of, as well as into, brain tissue. Competition between dopamine synthesis and L-DOPA egress from striatum must favor L-DOPA egress if decarboxylation declines relatively more than transport in Parkinson's disease. To test this hypothesis, we injected patients with Parkinson's disease with a radidabeled analogue of L-DOPA and recorded regional brain radioactivity as a function of time by means of positron emission tomography. We simultaneously estimated the activity of the decarboxylating enzyme and the amino acid transport. In the striatum of patients, we found the L-DOPA decarboxylase activity to be reduced in the head of the caudate nucleus and the putamen. However, the rate of egress of the DOPA analogue was unaffected by the disease and thus inhibited dopamine synthesis more than predicted in the absence of L-DOPA egress.