Fusarium sporotrichioides Sherb. and trichothecenes associated with Fusarium-ear rot of corn before harvest

Fusarium sporotrichioides was found to be the predominant fungus in approximately 2 % of corn ears damaged byFusarium species, before harvest during 1984 and 1985 in Poland. Concentrations of up to 1,714.9 mg/kg of total type-A trichothecenes (T-2 Toxin, HT-2 Toxin, Neosolaniol, T-2 Triol, and T-2 Tetraol) were found in hand-selected, heavily damaged kernels obtained fromF. sporotrichioides-molded ears.     

Immunoglobulin levels in various clinical groups of human Brugian filariasis in Malaysia

Quantitation of serum immunoglobulin M, G, A, D and E levels was carried out in Malaysians with Brugia malayi infections. Results showed highly elevated levels of IgM and IgE as well as moderately elevated levels of IgG. These were most significant in patients with tropical pulmonary eosinophilia or elephantiasis. Serum IgE levels were extremely high in microfilaraemic patients (6,060 +/- 3,958 IU ml) probably due to a constant antigenic stimulation by dead and dying microfilariae.     

Complex between single-stranded DNA and gene 5 protein of bacteriophage M13 studied with linear dichroism and ultraviolet absorption

We have studied complexes between the gene 5 protein (gp5) of bacteriophage M13 and various polynucleotides, including single-stranded DNA, using ultraviolet absorption and linear dichroism. Upon complex formation the absorption spectra of both the protein and the polynucleotides change. The protein absorption changes indicate that for at least two of the five tyrosine residues per protein monomer the environment becomes less polar upon binding to the polynucleotides but also to the oligonucleotide p(dT)8. All gp5-polynucleotide complexes give rise to intense linear dichroism spectra. These spectra are dominated by negative contributions from the bases, but also a small positive dichroism of the protein can be discerned. The spectra can be explained by polynucleotide structures, which are the same in all complexes. The base orientations are characterized by a substantial inclination and propellor twist. The number of possible combinations of inclination and propeller twist values, which are in agreement with the linear dichroism results, is rather limited. The base orientations with respect to the complex axis are essentially different from those in the complex with the single-stranded DNA-binding protein gp32 of bacteriophage T4.     

Polarized fluorescence and absorption of macroscopically aligned Light Harvesting Complex II.

Polarized absorption and fluorescence measurements have been performed at 77 K on isotropic and anisotropic preparations of trimeric Light Harvesting Complex II (LHC-II) from spinach. The results enable a decomposition of the absorption spectrum into components parallel and perpendicular to the trimeric plane. For the first time, it is shown quantitatively that the strong absorption band around 676 nm is polarized essentially parallel to the plane of the trimer, i.e., the average angle between the corresponding transition dipole moments and this plane is at most 12 degrees. The different absorption bands for LHC-II should not be considered as corresponding to individual pigments but to collective excitations of different pigments. Nevertheless, the average angle between the Qy transition dipole moments of all chlorophyll a pigments in LHC-II and the trimeric plane could be determined and was found to be 17.5 degrees +/- 2.5 degrees. For the chlorophyll b pigments, this angle is significantly larger (close to 35 degrees). At 77 K, most of the fluorescence stems from a weak band above 676 nm and the corresponding transition dipole moments are oriented further out of plane than the dipole moments corresponding to the 676-nm band. The results are shown to be of crucial significance for understanding the relation between the LHC-II structure and its spectroscopy.     

世居及移居高原青少年最大有氧能力的特征

本文报道海拔３４１７ｍ和４２８０ｍ地区世居藏族和移居汉族青少年运动状态下心肺功能的对比研究。结果显示：３４１７ｍ和４２８０ｍ世居藏族的最大氧耗量、无氧阈值及最大心输出量都明显大于汉族,血氧饱和度（Ｓａｏ２）随运动负荷的增加而降低。海拔３４１７ｍ藏、汉族的△Ｓａｏ２分别为７．４６％和１０．０３％,４２８０ｍ处为８．５７％和１３．７５％,最大心率随海拔升高而下降。研究提示,藏族青少年有较高的最大有氧能力,反映了他们对低氧环境的适应优势。     

Studies on humoral immunity against Taenia taeniaeformis infection in rats

Rats were infected with doses of 100, 1000, 5000 and 10 000 eggs of Taenia taeniaeformis. Haemagglutinating antibody to cysticerus antigen was detected at the 4th week of infection. The appearance and levels of antibody titre did not vary greatly with the infective dose. An IgM peak appeared at the 6th week, with IgG appearing slightly later and continuing to rise. Transfer of serum from the 1st week onwards from infections with 1000 eggs however could confer significant protection. Dilutions of hyperimmune serum (1 ml volumes) of up to 1/32 conferred significant protection on normal recipients. Hyperimmune serum transferred up to 4 days before challenge could confer 80% protection whereas serum transferred 4 days after challenge was totally non-protective. The significance of this finding is discussed in the light of current knowledge of metacestode immunity.     

Brugia malayi and Brugia pahangi: transmission blocking activity of ivermectin and brugian filarial infections in Aedes aegypti

Brugia malayi- or Brugia pahangi-infected, microfilaremic jirds (Meriones unguiculatus) were treated with ivermectin at a single dose of 200 micrograms/kg body weight, administered subcutaneously. After different time intervals, Aedes aegypti mosquitoes were fed on treated or untreated jirds. Sausage stage, L2, and L3 larvae failed to develop in mosquitoes that fed on jirds from 15 to 30 days post-treatment. After 1 month, the numbers of L3 larvae recovered from mosquitoes fed on treated B. pahangi jirds were comparable to controls. However, the number of L3's recovered from mosquitoes fed on B. malayi jirds remained significantly lower than controls, 2 and 3 months after treatment. This reduction suggests that ivermectin may be more effective in blocking transmission of B. malayi than B. pahangi. Ivermectin treatment had no effect on the mean number of circulating microfilariae in treated jirds. Therefore, mosquitoes ingested comparable numbers of microfilariae when compared to those mosquitoes fed on untreated controls. Only in the case of jirds infected with B. malayi did the circulating microfilarial counts fall 30 days after treatment. The failure of microfilariae to develop to the L3 stage in mosquitoes fed on jirds within 30 days of treatment was not due to failure of mosquitoes to ingest microfilariae. Brugia malayi microfilariae also failed to develop to L3 in mosquitoes that were allowed to feed on microfilaremic jird blood treated with ivermectin (50 ng/ml) in vitro, indicating its efficacy at low concentrations. In addition to N-acetyl glucosamine, microfilariae obtained for a period of 15 days from ivermectin-treated but not control jirds showed D-mannose, N-acetyl galactosamine, and L-fucose moieties on the surface of the sheath.(ABSTRACT TRUNCATED AT 250 WORDS)     

The phylogeny of the ant tribe Formicini (Hymenoptera: Formicidae) with the description of a new genus

Abstract. The holarctic ant tribe Formicini is revised, the new genus Bajcaridris described, and possible phylogenetic relationships are discussed. The subgenus Iberoformica is synonymized with Formica. A synopsis, diagnosis and keys to the genera are provided.