Inflammation markers in the serum of salt miners

The inflammation markers alpha-1-antitrypsin (AAT), Clara cell protein (CC-16), soluble interleukin-2-receptor (IL-R) and the soluble adhesion molecule E-selectin, the intercellular adhesion molecule (ICAM-1) and the vascular adhesion molecule (VCAM-1) were determined in the serum of 195 salt-exposed miners to analyse dose-response relationships between markers and potash dust. Alpha-1-antitrypsin, Clara-cell protein, IL2-R, E-selectin and VCAM-1 were not changed by salt exposure, however the ICAM-1 level in the serum fell slightly as the salt exposure increased. This effect was strongest in the group of smokers, still visible in the group of ex-smokers, no effect was seen in non-smokers. Markers, with the exception of VCAM-1, were influenced by tobacco exposure. Since markers were not elevated in relation to salt dust exposure, the results do not support an inflammatory effect of potash dust on the respiratory system.     

Influence of strong bases on the synthesis of silver nanoparticles (AgNPs) using the ligninolytic fungi Trametes trogii

Silver nanoparticles (AgNPs) were biosynthesized using fungal extract of Trametes trogii, a white rot basidiomycete involved in wood decay worldwide, which produces several ligninolytic enzymes. According to previous studies using fungi, enzymes are involved in nanoparticles synthesis, through the so-called green synthesis process, acting as reducing and capping agents. Understanding which factors could modify nanoparticles’ shape, size and production efficiency is relevant. The results showed that under the protocol used in this work, this strain of Trametes trogii is able to synthesize silver nanoparticles with the addition of silver nitrate (AgNO₃) to the fungal extract obtained with an optimal incubation time of 72 h and pH 13, using NaOH to adjust pH. The progress of the reaction was monitored using UV–visible spectroscopy and synthesized AgNPs was characterized by scanning electron microscope (SEM), through in-lens and QBDS detectors, and energy-dispersive X-ray spectroscopy (EDX). Additionally, SPR absorption was modeled using Mie theory and simple nanoparticles and core-shell configurations were studied, to understand the morphology and environment of the nanoparticles. This protocol represents a simple and cheap synthesis in the absence of toxic reagents and under an environmentally friendly condition.     

Bacterial interactions with silver

Summary This review examines interactions between bacteria and the biologically non-essential metal, silver. Aspects of silver toxicity, tolerance and accumulation (possible binding and uptake as opposed to energy-dependent transport) in bacteria are discussed. In addition, plasmid biology is examined briefly since little information is available on the exact mechanism(s) of plasmid-endoced silver resistance in bacteria.     

Transformation and regeneration of Brassica rapa using Agrobacterium tumefaciens

Summary Transformation and regeneration procedures for obtaining transgenic Brassica rapa ssp. oleifera plants are described. Regeneration frequencies were increasedby using silver nitrate and by adjusting the duration of exposure to 2,4-D. For transformation, Agrobacterium tumefaciens strain EHA101 containing a binary plasmid with the neomycin phosphotransferase gene (NPT II) and the b-glucuronidase gene (GUS) was cocultivated with hypocotyl explants from the oilseed B. rapa cvs. Tobin and Emma. Transformed plants were obtained within three months of cocultivation. Transformation frequencies for the cultivars Tobin and Emma were 1–9%. Evidence for transformation was shown by NPT II dot blot assay, the GUS fluorometric assay, Southern analysis, and segregation of the kanamycin-resistance trait in the progeny. The transformation and regeneration procedure described here has been used routinely to transform two cultivars of B. rapa and 18 cultivars of B. napus.     

酸性水和投加铝、钙对鲢鱼早期发育和鳃超微结构的影响

在实验室条件下,研究了酸性水和投加铝、钙对鲢鱼胚胎孵化和鱼苗存活以及幼鱼鳃超微结构的影响。pH4.0引起所有胚胎在24小时内死亡,暴露于pH4.5—6.0的胚胎孵化率和暴露于pH4.0—6.0的5—15日龄鱼苗存活率随pH值上升而增高。投加0.5mg Al~(3+)/L使在酸性pH暴露条件下的胚胎孵化率和鱼苗存活率进一步降低。投加3.0mg Ca~(2+)/L可显著提高暴露于pH4.5和5.0的胚胎孵化率;投加2.0mg Ca~(2+)/L可在一定程度上提高暴露于pH4.5和5.0的鱼苗存活率。幼苗经pH4.5暴露8小时后出现严重的鳃超微结构损害;投加1.0mg Al~(3+)/L使鳃结构损害加剧;投加5.0mg Ca~(2+)/L可明显缓解酸性水对鳃的损害。     

鲢、鳙在天然条件下的摄食强度(Ⅱ)武汉东湖鲢、鳙周年摄食强度的研究

武汉东湖的鲢(Hypophthalmichthy molitrix)鳙(Aristichthys nobilis)在天然条件下摄食强度具季节性变化。摄食强度高峰处于夏季,低谷处于冬季。在实验条件下,按周年采样期间水温变化范围,测定鱼的肠管排空率。食物通过鱼肠管时间(Y_p—h)与水温(X_t—℃)的关系为: 鲢Y_p=270.63 X_t~(0.6408) 鳙Y_p=280.46 X_t~(0.6642) 根据修正后Bajkov公式(D=C (24.A)/n),估算鱼的日粮。鱼日粮(Y_D)与水温(X_t)关系为: 鲢Y_D=0.2683e~(0.1503X_t) 鳙Y_D=0.0075X_t~(2.2715) 计算鱼在天然条件下周年月粮及年粮。鲢、鳙对天然饵料年消耗量分别为18.924公斤及17.39公斤,饵料系数分别为18.02及13.38。     

白鹇距长与年龄的关系

注意到白鹧雄鸟距长在一定时期内随年龄增长的事实,本文根据相邻2年同一月龄之间有12个月的间隔,距长数据除有较为集中外一定又有组间明显差别的特点,推测估计部分标本之年龄,加上确知年龄的部分标本,共测定89个个体120个距长样本数据,得到距长随年(月)龄增长的关系式:SL=am/1+bm,用此式可以实测距长初步估计野外采集到的白鹇个体的年龄     

Dinuclear silver(I) complexes of 24-membered bibracchial tetraimine Schiff base macrocycles derived from 2,5-diformylthiophene

The cyclocondensation of 2,5-diformylthiophene and the amines N,N-bis-(2-aminoethyl)-2-phenylethylamine, N,N-bis-(2aminoethyl)-t-butyl-amine and N,N-bis-(2-aminoethyl)-t-butyl-amine in the presence of silver(I) salts yields homodinuclear bibracchial tetraimine Schiff base macrocyclic complexes. The structures of two such complexes are also reported. The complex Ag₂L⁴(NO₃)(PF₆) (2) crystallises in the triclinic space group , No. 2) and has unit-cell dimensions a = 12.834(6), B = 13.183(6), C = 14.588(7) Å, = 64.86(4), β = 79.77(4), γ = 69.44(3)° with Z = 2; there is a monodentate and singly bridging nitrate anion present and the Ag---Ag separation is 4.161 Å. The complex Ag₂L⁴(CH₃CN)₂(BF₄)₂·CH₃CN (9) crystallises in the triclinic space group , No. 2) and has unit-cell dimensions a = 9.297(4), B = 12.985(3), C = 21.770(5) Å, = 91.570(10), β = 92.33(3), γ = 97.92(3) ° with Z = 2; there is a strongly bonded acetonitrile molecule coordinated to each silver atom and the Ag---Ag separation is 4.920 Å.     

Prevalence of fungi in carpeted floor environment: Analysis of dust samples from living-rooms,bedrooms, offices and school classrooms

The results of 100 carpet dust analyses from atopic individuals' environment were compared according to the sampling period or the location. Dust samples were collected with a standard domestic vacuum cleaner, in locations with carpeted floor: in residences (living-room and/or bedroom), in school classrooms and in offices. The quantities of fungi vary from 5000 CFU/g to 66 000 000 CFU/g of dust. More than 100 species were isolated by dilution plating. The main species found in carpet dust wereEurotium repens, Penicillium chrysogenum, Alternaria alternata, Aureobasidium pullulans andPhoma herbarum. Strict xerophilic species were rather rare and detected in small quantities. Differences in the distribution of the CFU concentrations were examined for the four different sampling locations and were statistically significant (P=0.0174). In this study, schools were open spaces, and offices, mostly with air conditioning systems, were locations in which air is not confined. This, added to frequent professional carpet cleaning, probably explains the lowest levels of fungal concentration found in these locations. The majority of the homes had the largest fungal concentration in the living-room (median: 2×10⁵ CFU/g) while some bedrooms (median: 7×10⁴ CFU/g) had the highest concentrations. It is suggested that, when fungi are suspected to be the origin of respiratory allergy or irritating symptoms, the mycoflora of the bedroom, principally, should be investigated first.     

Prevalence of fungi in carpeted floor environment: analysis of dust samples from living-rooms,bedrooms, offices and school classrooms

The results of 100 carpet dust analyses from atopic individuals' environment were compared according to the sampling period or the location. Dust samples were collected with a standard domestic vacuum cleaner, in locations with carpeted floor: in residences (living-room and/or bedroom), in school classrooms and in offices. The quantities of fungi vary from 5000 CFU/g to 66 000 000 CFU/g of dust. More than 100 species were isolated by dilution plating. The main species found in carpet dust wereEurotium repens, Penicillium chrysogenum, Alternaria alternata, Aureobasidium pullulans andPhoma herbarum. Strict xerophilic species were rather rare and detected in small quantities. Differences in the distribution of the CFU concentrations were examined for the four different sampling locations and were statistically significant (P=0.0174). In this study, schools were open spaces, and offices, mostly with air conditioning systems, were locations in which air is not confined. This, added to frequent professional carpet cleaning, probably explains the lowest levels of fungal concentration found in these locations. The majority of the homes had the largest fungal concentration in the living-room (median: 2×10⁵ CFU/g) while some bedrooms (median: 7×10⁴ CFU/g) had the highest concentrations. It is suggested that, when fungi are suspected to be the origin of respiratory allergy or irritating symptoms, the mycoflora of the bedroom, principally, should be investigated first.