Structural studies and physiological activity of lemnan, a pectin fromLemna minor L

A pectic polysaccharide, lemnan, was isolated from freshly collected duckweedLemna minor L. Its sugar chain was shown to be mainly composed of the residues ofD-galacturonic acid (64%), galactose, arabinose, xylose, andD-apiose, a branched chain sugar. The high content ofD-apiose (25%) indicated that lemnan is an apiogalacturonan type pectin similar to zosteran, a pectic polysaccharide from a sea phanerogam of the Zosteraceae family. The results of partial acidic hydrolysis, pectinase digestion, and NMR studies of lemnan demonstrated that its macromolecule contains regions of the linear α-1,4-D-galacturonan and branched apiogalacturonan. The side chains of apiogalacturonan were found to be formed of single and 1,5-linked residues ofD-apiofuranose attached to 2- and 3-positions of theD-galacturonic acid residues of the apiogalacturonan backbone. Lemnan was shown to exhibit an immunomodulatory effect activating the system of phagocytosis.     

蚕豆在重金属污染条件下数量性状的分化研究

运用正交设计方法,经过４代的原位种植实验,研究了在人工控制条件下Ｐｂ＾２＋、Ｃｄ＾２＋、Ｈｇ＾２＋、Ｚｎ＾２＋对同一蚕豆种质在株高、首次开花时间、每株结豆荚数、单位豆荚豆数数（每２０个豆荚）、种子的重量（５０粒）等数量性状的代内和代间分化,实验结果表明,在初始种植代仙,低深度的重金属除使开花时间以外的各数量性状指标程度不同有刺激升高作用;高浓度则使性状明显受到抑制。对于属除使开花时间以外的各数量性     

Identification of glyoxalase 1 polymorphisms associated with enzyme activity

The glyoxalase system and its main enzyme, glyoxalase 1 (GLO1), protect cells from advanced glycation end products (AGEs), such as methylglyoxal (MG) and other reactive dicarbonyls, the formation of which is increased in diabetes patients as a result of excessive glycolysis. MG is partly responsible for harmful protein alterations in living cells, notably in neurons, leading to their dysfunction, and recent studies have shown a negative correlation between GLO1 expression and tissue damage. Neuronal dysfunction is a common diabetes complication due to elevated blood sugar levels, leading to high levels of AGEs. The aim of our study was to determine whether single nucleotide polymorphisms (SNPs) in the GLO1 gene influence activity of the enzyme. In total, 125 healthy controls, 101 type 1 diabetes, and 100 type 2 diabetes patients were genotyped for three common SNPs, rs2736654 (A111E), rs1130534 (G124G), and rs1049346 (5′-UTR), in GLO1. GLO1 activity was determined in whole blood lysates for all participants of the study.     

Turkish graveyards as refuges for orchids against tuber harvest

Harvest of orchid tubers for salep production is widespread in southwestern Asia and the Balkans and constitutes a major conservation risk for wild orchid populations. Synanthropic habitats, such as graveyards, are important refuges for orchids and other organisms and could offer protection from salep harvesting because of their special cultural role. However, little is known about the occurrence and factors influencing harvesting of salep in graveyards. During field surveys of 474 graveyards throughout Turkey, we observed 333 graveyards with orchids, 311 graveyards with tuberous orchids, and salep harvest in 14 graveyards. Altogether, 530 individuals of 17 orchid species were collected, representing 9% of the individuals recorded. Harvesting intensity was relatively low, and populations were usually not wholly destroyed. However, some species were clearly more affected than others. Salep harvesting risk of orchid species was significantly associated with flowering time, with early‐flowering species being more affected. A marginally significant positive relationship between harvesting risk and species‐specific tuber size was also detected. Our data suggest that graveyards might offer some protection against salep harvesting in Turkey, but they also show that some orchid taxa are much more affected than others. Overall, our observations add more weight to the conservation value of these special habitats.     

西沙群岛东岛小军舰鸟繁殖种群的初步观察

2003年3-4月对西沙群岛的鸟类资源进行了考察,在西沙群岛的东岛发现小军舰鸟(Fregata minor)繁殖,为迄今所知该种在我国仅有的繁殖记录。野外观察共发现7个巢,其中5个巢中途毁损,另见幼鸟13只,非繁殖雄性个体2只。还观察到小军舰鸟与红脚鲣鸟相互影响的负面行为,如抢食、窃巢材等。调查结果显示,西沙群岛小军舰鸟分布范围现已缩小,而且种群数量显著下降。     

蚕豆叶片小叶脉不同发育时期ATP酶和酸性磷酸酶的细胞化学超微结构定位

运用CF输导方法确定正在进行库源转换的叶片。采用铅沉淀法对蚕豆(Vicia faba)幼嫩叶片、库源转换叶的库区和源区的小叶脉组织细胞进行了ATP酶和酸性磷酸酶的细胞化学定位。结果显示, 在蚕豆幼嫩叶片的小叶脉中, 传递细胞质膜和细胞壁上存在大量的ATP酶和酸性磷酸酶的标记产物。在库源转换叶库区传递细胞和筛分子质膜上ATP酶和酸性磷酸酶的标记较弱。在库源转换叶的源区传递细胞和筛分子质膜存在较强的ATP酶和酸性磷酸酶的活性反应产物。在小叶脉分化中的木质部分子存在较强的ATP酶和酸性磷酸酶的活性标记, 在分化成熟的木质部分子酶的标记显著减弱。实验结果表明, 依据不同的发育阶段, ATP酶和酸性磷酸酶的含量在蚕豆小叶脉的不同细胞中呈动态变化。据此, 对ATP酶和酸性磷酸酶在蚕豆小叶脉细胞分化和质外体装载中的作用进行了讨论。     

Effects of artificial ultraviolet-B radiation on growth and fatty acid composition of duckweed (Lemna minor)

1. Duckweed (Lemna minor), collected either in summer or early fall was exposed under laboratory conditions to control (photosynthetically active and UV‐A radiation) or experimental (control plus UV‐B radiation) conditions. 2. Growth and survival were determined by counting the number of green, and brown/white fronds following 1–5 or 11 days of irradiation. Growth of duckweed was impaired by exposure to UV‐B radiation in the fall experiment but not in the summer. 3. Fatty acid compositions were analysed following 5 or 11 days of irradiation and a recovery period of 0, 5, 29 or 40 h. Concentrations of the major fatty acids, palmitic, linoleic (LA) and α‐linolenic (ALA) acids were similar in the summer and fall duckweed collections, but the summer samples had higher concentrations of the desaturation products of LA and ALA. 4. UV‐B exposure had small, but significant, and contrasting effects on duckweed fatty acid concentrations. In the summer experiment, duckweed exposed to UV‐B had slightly lower concentrations of major fatty acids than control duckweed, while the reverse was true in the fall experiments. 5. These minor effects of UV‐B on concentrations of LA and ALA would be unlikely to have a major impact on the supply of these essential fatty acids from duckweed to freshwater food webs.     

New theory of uterovaginal embryogenesis

Background: The explanation of uterine and vaginal embryogenesis in humans still poses many controversies, because it is difficult to assess early stages of an embryo. The literature review revealed many disagreements in Mullerian theory, inciting some authors to propose new embryological hypotheses. In the original Mullerian theory: the paramesonephral ducts form the Fallopian tubes, uterus and vagina; the mesonephral ducts regress in female embryos. Aims: The aim of this article is to investigate the development of Mullerian ducts in humans, using comparative analysis of fundamental embryological theory and various utero-vaginal anomalies. Material and methods: Between 1998 and 2015, 434 patients with various uterovaginal malformations had been operated on at the Scientific Centre of Obstetrics Gynaecology and Perynatology in Moscow. The anatomies of the uterovaginal malformations in these patients were diagnosed with ultrasound and MRI and then verified during surgical correction by laparoscopy. Results: A systematic comparison of uterovaginal malformations to those in the literature has allowed us to formulate a new theory of embryonic morphogenesis. The new theory is significantly different: ovary, ovarian ligamentum proprium, and ligamentum teres uteri derive from gonadal ridges; Fallopian tubes and vagina completely develop from mesonephral ducts. The uterus develops in the area of intersection between the mesonephral ducts with gonadal ridges by the fusion of the two. Conclusions: The new theory may to induce future embryological studies. The hypothetic possibility that the ovary and endometrium derive from the gonadal ridges could be the key to understanding the enigmatic aetiologies of extragenital and ovarian endometriosis.     

Congenital cataracts in a free-ranging rhesus monkey

This report documents the occurrence of congenital cataracts in a visually-impaired yearling rhesus monkey from the same matriline on Cayo Santiago in which a congenitally blind infant was born 2 years previously.