Degradation of extractive-free lignocelluloses by Coriolus versicolor and Poria placenta

Summary The wood-decay fungi Coriolus versicolor, a white-rot fungus, and Poria placenta, a brown-rot fungus, were grown on an extractive-free lignocellulose prepared from quackgrass (Agropyron repens). Their abilities to decompose this lignocellulose were compared to their abilities to decompose softwood (Picea pungens) and hardwood (Acer rubrum) lignocelluloses. The two fungi were grown on malt-extract dampened lignocelluloses at 28°C for up to 12 weeks. Replicate cultures were periodically harvested and lignocellulose decomposition was followed by monitoring substrate weight loss, lignin loss, and carbohydrate loss. Coriolus versicolor decomposed the lignin and carbohydrate components of the grass lignocellulose as efficiently as the softwood and hardwood lignocelluloses. Poria placenta, however, was not an efficient degrader of either lignin or carbohydrate in the grass lignocellulose. Poria placenta readily decomposed carbohydrate components of the softwood lignocellulose but not the hardwood lignocellulose.Paper number 81520 of the Idaho Agricultural Experiment Station     

Some observations on the effect of Daflon (micronized purified flavonoid fraction of Rutaceae aurantiae) in bancroftian filarial lymphoedema

BACKGROUND: Morbidity management is a core component of the global programme for the elimination of lymphatic filariasis. In a double-blind clinical trial, the tolerability and efficacy of Daflon (500 mg) + DEC (25 mg) or DEC (25 mg) alone, twice daily for 90 days, was studied in 26 patients with bancroftian filarial lymphoedema. RESULTS: None of the patients in either drug group reported any adverse reaction throughout the treatment period (90 days). Haematological and biochemical parameters were within normal limits and there was no significant difference between the pre-treatment (day 0) and post-treatment (day 90) values. The group receiving Daflon showed significant reduction in oedema volume from day 90 (140.6 PlusMinus; 18.8 ml) to day 360 (71.8 PlusMinus; 20.7 ml) compared to the pre-treatment (day 0, 198.4 PlusMinus; 16.5 ml) value. This accounted for a 63.8% reduction in oedema volume by day 360 (considering the pre-treatment (day 0) as 100%). In the DEC group, the changes in oedema volume (between day 1 and day 360) were not significant when compared to the pre-treatment (day 0) value. The percentage reduction at day 360 was only 9%, which was not significant (P > 0.05). CONCLUSION: This study has shown that Daflon (500 mg, twice a day for 90 days) is both safe and efficacious in reducing oedema volume in bancroftian filarial lymphoedema. Further clinical trials are essential for strengthening the evidence base on the role of this drug in the morbidity management of lymphatic filariasis.     

Negative effects of oil spillage on beach microalgae in Nigeria

In a concerted effort to apply epipsammic microalgae indices as a biological indicator of crude oil pollution and natural remediation in a tropical estuarine environment, the direct effect of a recent oil spill on the abundance of microalgae in the coastal shore of the Qua Iboe Estuary was investigated. A significant negative effect of contamination on the salinity, acidity and nutritive salts (CO₃²⁻, Cl⁻, and SO₄²⁻) levels of the sandy beach soil was observed. The Biological Index of Pollution (BIP) of the beach soil was raised from the previous slightly polluted level (18%) to 75, 88, 45 and 41% after contamination, at sampling distances of 5.5, 9.5, 11.5 and 15 m from the barrier used for pollution control. These corresponded with increases in the density of microalgae with distance from the barrier. This implies that the effect of oil pollution was more severe on microalgal cells that are close to the barrier. The overall effect was a distance-influenced reduction in the regeneration capabilities of the epipsammic microalgae. Some microalgal species, particularly the cyanobacterial species of Aphanizomenon flos-aquae, Lyngbya majusculata,and a centric diatom Actinoptychus undulatus may have been exposed to contamination levels exceeding normal homeostasis and compensation. They lost their existence in the sandy beach, and their absence is recommended for use as an indicator of the short term effect of oil pollution in coastal sandy beaches in a tropical estuarine environment.     

水螅刺丝囊的分离与观察

水螅的刺丝囊依据其形态和功能,有穿刺丝囊、钩刺丝囊、粘刺丝囊和卷刺丝囊4种,是淡水水螅分类的主要依据之一.使用多种化学试剂探索分离刺丝囊的方法,实验发现利用10%的MgSO4或3%的NaCl处理离体触手5～6 min,用高纯水清洗后制作装片观察,可以获得最佳的显微图片和观察效果.最后初步探讨了不同体区刺丝囊的结构特点.     

Incidence of infantile diarrhoea due to enteropathogenic Escherichia coli in Port Harcourt metropolis

Five hundred diarrhoeal stool samples from the University of Port Harcourt Teaching Hospital were investigated for enteropathogenic Escherichia coli. Results showed that the organism was endemic in Port Harcourt metropolis and was responsible for about 15% of the incidence of infantile diarrhoea in the community. Detailed analysis revealed that 13 serotypes were involved. It was also observed that babies aged between 0 and 18 months were more susceptible than those aged between 19 and 36 months. Male infants were also shown to be more at risk than females. Antibiotic sensitivity tests showed that the enteropathogenic E. coli isolated were highly resistant to most common antimicrobial drugs but were highly sensitive to genticin and cefotaxime.     

Microalgae biodiversity and biomass status in Qua Iboe Estuary mangrove swamp,Nigeria

Microalgae composition, abundance, diversity and biomass of the Qua Iboe Estuary mangrove swamp were studied. The results revealed the rich assemblage of the brackish ecosystem. Six major taxanomic classes were encountered. These were the Bacillariophyceae, Cyanophyceae, Chlorophyceae, Chrysophyceae, Euglenophyceae and Phaeophyceae. Their composition, abundance and diversity exhibits strong seasonal variation. Variations between pelagic and sedimentary habitats were also noticed. The diatoms (Bacillariophyceae) dominated the habitats. Actinoptychus undalatus, Navicula radiosa and Amphora ovalis co-dominated the pelagic water column; while the epipellic (intertidal) and benthic (subtidal) sediments were co-dominated by A. ovalis and Actinoptychus undulatus. Analyses of the Shannon’s index of general diversity (H¹), McArthur-Terborgh species equitability index (E) and Simpson’s index of dominance (D) of the microalgae communities revealed that A. ovalis with a mean H ¹ -value of 0.25, E-value of 0.08 and D-value of 0.05 was the most prevalent genus in the mangrove ecosystem despite its uneven distribution. The densities of the microalgae communities corresponded with their biomass statuses and were seriously impacted by oil spillage. This forms the basis of concern because the estuary is associated with a high probability of major oil pollution with serious consequences for ecological stability and fisheries.     

Sampling properties of DNA sequence data in phylogenetic analysis

We inferred phylogenetic trees from individual genes and random samples of nucleotides from the mitochondrial genomes of 10 vertebrates and compared the results to those obtained by analyzing the whole genomes. Individual genes are poor samples in that they infrequently lead to the whole-genome tree. A large number of nucleotide sites is needed to exactly determine the whole-genome tree. A relatively small number of sites, however, often results in a tree close to the whole-genome tree. We found that blocks of contiguous sites were less likely to lead to the whole-genome tree than samples composed of sites drawn individually from throughout the genome. Samples of contiguous sites are not representative of the entire genome, a condition that violates a basic assumption of the bootstrap method as it is applied in phylogenetic studies.