鹅毛竹大小孢子及雌雄配子体发育

利用扫描电镜、透射电镜、石蜡切片,对鹅毛竹的花芽分化、大、小孢子及雌、雄配子体的发育进行了详细观察.结果发现:鹅毛竹花药具4个药室,花药壁由表皮、药室内壁、中层、绒毡层4层结构组成,花药壁发育为单子叶型,绒毡层为腺质型,小孢子母细胞减数分裂中的胞质分裂为连续型,产生左右对称型小孢子.鹅毛竹成熟花粉大多2细胞型,都具1个萌发孔.鹅毛竹子房为单子房,子房1室,侧膜胎座,一个倒生胚珠,双珠被,薄珠心.大孢子母细胞由一个雌性孢原细胞直接发育而成,大孢子四分体呈线型,合点端一个大孢子分化为功能大孢子,由功能大孢子经过3次有丝分裂形成8核胚囊,发育类型为蓼型,位于核点端的3个细胞核进行多次分裂形成多个反足细胞.至此,成熟胚囊形成.并就鹅毛竹不结实的原因进行了探讨.     

多药耐药基因的转录调控与治疗学机会

人肿瘤多药耐药mdr-1基因的转录调控机制复杂。多个正调控和负调控元件与转录因子的相互作用、表遗传学因素的参与等共同决定着人mdr-1基因表达的组织、细胞和刺激的特异性和依赖性。同时,也为特异或相对特异性地防止／抑制肿瘤细胞的mdr-1基因表达、克服肿瘤多药耐药性提供了基础。新抗肿瘤药物沙尔威辛和ET-743有力地诠释了控制mdr-1基因转录所蕴藏的治疗学机会。     

Before it disappeared: ethnobotanical study of fleagrass (<Emphasis Type="Italic">Adenosma buchneroides</Emphasis>), a traditional aromatic plant used by the Akha people

Background

Fleagrass, Adenosma buchneroides, is an aromatic perennial herb that occupies an important position in the life of the Akha people. They regard it as a tribal symbol and a gift of love. Fleagrass also has many medicinal uses, and there is considerable potential for its development as an insect repellent. Traditionally, Akha people plant it in swidden fields, but there are few swidden fields in China now. Therefore, the first question this study aims to answer is as follows: how is fleagrass planted and utilized now? At present, fleagrass is only reported to be used by Akha people in Mengla. We also try to understand the following questions: Is fleagrass used in nearby area? If so, how is fleagrass used in nearby area? Furthermore, why is fleagrass used in that way?

Methods

From August 2016 to July 2018, field surveys were conducted six times. The ethnobotanical and ethnopharmacological uses of A. buchneroides in 13 Akha villages were investigated by means of semi-structured interviews. We assessed the responses of a total of 64 interviewees (32 men and 32 women; mean age, 58.6) from the Xishuangbanna Dai Autonomous Prefecture, southwest China, and from Phongsaly Province, Laos. To explain the bases for the ethnobotanical uses of fleagrass, we used Google Scholar, Web of Science, and China National Knowledge Infrastructure to review the bioactivities of the chemical constituents of A. buchneroides.

Results

With the vanishing of swidden agriculture and the development of modern products, fleagrass cultivation is disappearing in China. However, most Akha people in Xishuangbanna still remember and yearn for its traditional uses, and Akha people in a nearby area (northern Laos) continue to plant and utilize it. We documented ten uses of A. buchneroides within five discrete categories. The whole plant of fleagrass has a distinct strong aroma, of which Akha villagers are particularly fond. Akha villagers mostly use this aromatic property as a decoration, perfume, and insect repellent. A. buchneroides is also used as a condiment and for medicinal and ritual purposes, including its use as a cure for insect bites, headaches, influenza, and diarrhoea, and as a part of pray ritual for a bumper harvest. From our literature review, we identified many major chemical compounds contained in the essential oil of A. buchneroides, including thymol, carvacrol, 3-carene, and p-cymene, which have insecticidal or insect-repellent, antimicrobial, and anti-inflammatory properties.

Conclusion

Fleagrass is an aromatic plant that is widely used by Aka people. Its chemical composition also has a variety of biological activities. With the vanishing of swidden agriculture and the development of modern products, fleagrass utilization in China is disappearing and its cultural importance is reduced. However, its economic and medicinal value is assignable.

     

1株高效降解纤维素的槲寄生内生真菌研究

利用刚果红-CMC平板染色法、DNS法从槲寄生内生真菌中筛选获得1株高效纤维素酶产生菌H-3-3,通过分析其菌落形态特征和18S rDNA序列的同源性,将菌株H-3-3鉴定为拟茎点霉属Phom opsissp.;对其酶学性质研究得到：槲寄生内生真菌H-3-3中CMC酶、β-葡糖苷酶、滤纸酶这3种组分酶最适温度均为50℃,β-葡糖苷酶活和滤纸酶活最适pH值均为4.8,CMC酶最适pH值为4.4;3种酶在30～45℃,pH4.0～8.0稳定性较强。金属离子Mn^2＋、Co^2＋、Mg^2＋和Ca^2＋对3组分酶都有不同程度的促进作用,其中以Co^2＋效果最佳;而Ba^2＋、Zn^2＋、Cu^2＋对3组分酶分均表现出明显的抑制作用。     

七种秋石斛鲜花挥发性成分差异性分析

为查明秋石斛不同品种关键赋香成分,利用固相微萃取(SPME)方法结合GC-MS技术,测定了秋石斛5个具香气的品种,即绿天使(Dendrobium Hand Green)、日出2号(Dendrobium Burana Sunrise No.2)、白花607(Dendrobium K.B.White 607)、紫背256(Dendrobium Blue Sapphine 256)、魅力(Dendrobium Burana Charming)以及2个不具香气的品种,即红牛(Dendrobium Red Bull)、三亚阳光(Dendrobium Sunya Sunshine)盛花期的花朵挥发性成分及其相对含量。结果表明:共鉴定出45种挥发性化合物,其中萜烯类34种、芳香族化合物8种、酯类3种,5种具香气的秋石斛花朵所含挥发性成分绝大部分都是萜烯类,萜烯类对秋石斛的花香起着重要的作用。通过比较发现,5种具香气秋石斛的主要赋香成分为3-蒈烯、芳樟醇、α-可巴烯和α-法尼烯,不同品种挥发性成分的组成和含量明显不同。绿天使和日出2号的主要香气成分是3-蒈烯,相对含量分别为59.343%和77.775%,但日出2号中的释放率约为绿天使的3倍;白花607主要香气成分为3-蒈烯(29.170%)、α-可巴烯(17.660%)、芳樟醇(10.990%);紫背256中α-法尼烯相对含量最高(42.310%);魅力中主要香气成分是α-可巴烯(33.648%),邻苯二甲酸二异丁酯(13.866%)为其次。2个不具香气品种中鉴定出化合物较少,主要挥发性成分释放率较小;红牛主要挥发性成分是胡莫柳酯(28.118%),三亚阳光是异丁子香酚(27.529%)。这些主要挥发性成分对不同品种秋石斛花的特有香味起决定性作用,且大部分已被广泛应用于香精香料,医药,日化等产品中。该研究结果为香型秋石斛产品开发及品种的培育提供了参考。     

SMAD3 Is Associated with the Total Burden of Radiographic Osteoarthritis: The Chingford Study

Background

A newly-described syndrome called Aneurysm-Osteoarthritis Syndrome (AOS) was recently reported. AOS presents with early onset osteoarthritis (OA) in multiple joints, together with aneurysms in major arteries, and is caused by rare mutations in SMAD3. Because of the similarity of AOS to idiopathic generalized OA (GOA), we hypothesized that SMAD3 is also associated with GOA and tested the hypothesis in a population-based cohort.

Methods

Study participants were derived from the Chingford study. Kellgren-Lawrence (KL) grades and the individual features of osteophytes and joint space narrowing (JSN) were scored from radiographs of hands, knees, hips, and lumbar spines. The total KL score, osteophyte score, and JSN score were calculated and used as indicators of the total burden of radiographic OA. Forty-one common SNPs within SMAD3 were genotyped using the Illumina HumanHap610Q array. Linear regression modelling was used to test the association between the total KL score, osteophyte score, and JSN score and each of the 41 SNPs, with adjustment for patient age and BMI. Permutation testing was used to control the false positive rate.

Results

A total of 609 individuals were included in the analysis. All were Caucasian females with a mean age of 60.9±5.8. We found that rs3825977, with a minor allele (T) frequency of 20%, in the last intron of SMAD3, was significantly associated with total KL score (β = 0.14, P_permutation = 0.002). This association was stronger for the total JSN score (β = 0.19, P_permutation = 0.002) than for total osteophyte score (β = 0.11, P_permutation = 0.02). The T allele is associated with a 1.47-fold increased odds for people with 5 or more joints to be affected by radiographic OA (P_permutation = 0.046).

Conclusion

We found that SMAD3 is significantly associated with the total burden of radiographic OA. Further studies are required to reveal the mechanism of the association.     

植物膜Ca2+运输系统与逆境应答

主要介绍了细胞膜Ca2 运输系统的种类、分子结构及调控机制,并通过膜Ca2 运输系统与胞质Ca2 水平变化之间的关系评述了细胞膜Ca2 运输系统在植物应答逆境中的作用.     

钙对酸雨伤害甜瓜幼苗的影响

 本文研究了钙对酸雨伤害甜瓜幼苗的影响。30mmol/L CaCl2处理甜瓜幼苗2次,可明显减轻pH2.5酸雨对甜瓜幼苗的酸致损伤。实验结果显示,此与钙能提高甜瓜幼苗光合速率、叶绿素含量,增加CAT活性与叶片Ca2+含量,减少MDA含量,降低质膜透性,维持细胞汁pH值稳定性等多重生理生态效应有关。