Some Biochemical Abnormalities Caused by Cypermethrin in Adults of Tribolium castaneum (Herbst.)

Biochemical effects of sub lethal doses LC₁₀ and LC₂₀ of cypermethrin were studied on some enzymes and macromolecule activities of adult beetles of Tribolium castaneum (Herbst.). Cypermethrin caused disturbances in levels of all biochemical components under study. The dose of 0.78 ppm caused abnormalities in α‐amylase and FAA by increasing their activities i.e., 45.45% and 21.97% significantly. The higher sub lethal dose of 2.62 ppm disturbed all the parameters (AcP, α‐amylase, soluble protein and FAA) except AkP, which was decreased by 93.06%. Moreover, sub lethal doses either increased or decreased the levels of all parameters non‐significantly except AkP and FAA which were effected significantly by 87.92% and 14.29% at lower and higher doses, respectively. In the present studies, cypermethrin significantly enhanced the activity of AkP in both susceptible and resistant strains of T. castaneum adult beetles while FAA contents were increased significantly in resistant strain only. The activity of α‐amylase was significantly lowered in susceptible strain only.     

Soil algae from acid rain impacted forest areas of the Krušné hory Mts. 1. Algal communities

The soil algal communities of forested and reforested, limed and unlimed plots were compared in the acid rain impacted Kru sné hory Mountains. The floristic composition of unlimed plots is similar to that found in acid forest soils with a naturally low pH and no effect of the acid rain on these communities can be detected. Chlorophyceae are the only group present in these soils. In limed areas with a higher soil pH, algal diversity is significantly increased while algal densities remain similar. Chlorophyceae, while still the dominant group, are accompanied in these soils by Bacillariophyceae, Xanthophyceae, Eustigmatophyceae and Cyanophyceae. Total vegetation cover and thus light hitting the soil surface seems to be most important in determining the algal biomass.     

RNA partitioning accompanied by adsorption: high-molecular-mass RNA adsorbed at the interface like a particle

In a potassium phosphate-poly(ethylene glycol) (PEG) system, RNA partitioning was accompanied by adsorption at the interface, depending on the molecular mass. Low-molecular-mass RNA showed the typical partition behavior of a soluble substance. Conversely, high-molecular-mass RNA was significantly adsorbed at the interface in the potassium phosphate-PEG1500 system. The adsorbed amount was proportional to the added amount, regardless of the phase volume ratio. The partitioning of high-molecular-mass RNA showed an amount-ratio-dependent distribution like that of a particle.     

Serum antibodies to commensal oral and gut bacteria vary with age

Abstract Pyelonephritis is the most common urinary tract infection affecting females of all age groups. Despite concerted efforts the mechanism of renal injury in pyelonephritis is not clearly understood. In the present study we have made an attempt to characterise the mediators of inflammatory insult in an experimental model of ascending pyelonephritis. Mice infected with Escherichia coli O6:K13:H1 were sacrificed at 2, 7 and 14 days post-infection. Luminol-dependent chemiluminescence response, NADPH oxidase, acid phosphatase, β-glucuronidase and N -acetyl-β- d -glucosaminidase activities were monitored in circulating as well as renal phagocytic cells in order to determine the role of reactive oxygen species and lysosomal enzymes in genesis of renal injury. We have demonstrated that reactive oxygen species are generated at the initiation of infection and the levels increase progressively during the course of infection. While intracellular release of lysosomal enzymes was seen in all groups, extracellular release was primarily observed at 7 and 14 days post-infection only. The results indicate that while reactive oxygen species play a significant role in tissue injury during all stages of infection, lysosomal enzyme release in extracellular milieu augments tissue destruction at later stages only.     

植酸对稻米品质影响的研究（Ⅰ）

本文报道在水稻生长的抽穗期、齐穗期、灌浆期和蜡熟期喷施不同浓度植酸改良稻米品质的研究。结果表明,在水稻生长的不同阶段,控制喷施植酸浓度可提高糙米率,降低稻米垩白。     

Synthesis and comparative conformational energetics of D-phenylalanylsarcosine and its cyclic dehydration product, (R)-1-methyl-3-(phenylmethyl)-2,5-piperazinedione

Summary Synthetic protocols are presented both for D-PheSar and the corresponding cyclised diketopiperazine, prepared from N-t-butoxycarbonylprotected D-PheSar. Deprotection conditions could be manipulated to yield either D-Phenylalanylsarcosine or (R)-1-methyl-3-(phenylmethyl)-2,5-piperazinedione. Molecular modelling revealed several low energy conformers which contained a Z-peptide bond and which were readily amenable to cyclisation. Cyclisation was found by HPLC to be fastest in strongly acidic conditions.Abbreviation HBTU o-Benzotriazolyl-tetramethyluronium hexafluorophosphate     

Continuous culture of Humicola lutea 120-5 for acid proteinase production

Acid proteinase production by the fungus Humicola lutea 120-5 in continuous culture was studied. The maximum activity of the culture broth reached 2200 U/ml at a dilution rate (D) of 0.05/h. The continuous process was carried out for 1 month without any bacterial contamination, due to low pH (3.0–3.5) during the cultivation.     

甘蔗和烟草幼叶原生质体的核酸含量与核酸酶活性及其影响因素

与幼叶组织相比,酶法新鲜分离的甘蔗和烟草幼叶原生质体内的ＲＮＡ、ＤＮＡ及总核酸含量均降低。其原因可能是刚游离的原生质体内酸性和碱性ＲＮＡ酶与ＤＮＡ酶等活性提高所致。甘蔗叶原生质体内的核酸降低量和ＲＮＡ酶与ＤＮＡ酶活性的增加程度均高于烟草。随用作渗透压稳定剂的甘露醇浓度增加,甘蔗和烟草叶原生质体的ＲＮＡ酶和ＤＮＡ酶活性均相应提高。其中以甘蔗叶原生质体的核酸酶活性增加水平较明显。在细胞壁降解产物的作用下,除了甘蔗原生质体内的ＲＮＡ酶活性略被促进外,其ＤＮＡ酶和烟草叶原生质体内的核酸酶均不受影响     

Regio- and stereo-specific nitrile hydrolysis by the nitrile hydratase from Rhodococcus AJ270

Abstract Acid phosphatase activity was measured in individual cells by determining their optical densities through a scanning confocal laser microscope. The naphthol AS-TR (3-hydroxy-2-naphtoic acid 4'-chloro-2'-methylanilide) phosphate-hexazotized para-rosanilin method was used to visualise the acid phosphatase content in the light microscope. Evidence was obtained that the amount of enzyme varied in exponential growth phase cells as the fission age increased. By comparing the acid phosphatase activity with the rate of food vacuole formation, it appeared that the amount of enzyme inside the cells decreased in early clonal life, whereas the rate of food uptake increased. It was assumed that the reduction of acid phosphatase content could lead to a more extended life of vacuoles and to a decreased membrane recycling rate. In turn, the reduced supply of membrane available for food vacuole formation could partly be responsible for the decrease of the food uptake rate observed after the initial increase.     

促黄体素释放激素类似物(LH-RH-A)对人蜕膜组织核糖核酸和蛋白质合成的抑制作用

高剂量LH-RH-A可明显抑制人蜕膜组织在离体下对~3H-尿嘧啶和~3H-亮氨酸的摄取;低剂量LH-RH-A无明显影响。在人蜕膜组织中也发现有高亲合力(K_?=3.83±1.36×10~?M~(-1))的LH-RH-A特异受体。上述发现表明,高剂量LH-RH-A可通过直接抑制RNA和蛋白质的合成而调节蜕膜组织的功能。