中国陆生贝类一新种

作者于１９８１－１９８３年,参加中国科学院横断山综合考察队,赴云南地区进行考察又地１９９３－１９９４年,赴南一带调查获得陆生贝类一一批,经事理鉴定,得拟阿勇蛞蝓科一新种;即云龙ｒｙｐｔｏｚｏｎａ ｙｕｎｌｏｎｇｅｎｓｉｓ ｓｐ．ｎｏｖ．。。本文对新咱的形态特征作了详细描述,并对生殖系统进行了解剖,地颚片和齿舌作了电子显微镜民其近似种古怪隐带螺Ｃｒｙｐｔｏｚｏｎａ ｅｒｒａｔｉｃａ 进行了比较。     

广西砂螺属一新种(肺螺亚纲:柄眼目:虹蛹螺科)

作者于1999年在广西十万大山地区进行动物资源调查,获得一批陆生贝类,经鉴定得1新种,即扶隆砂螺Gastrocopta fulongensis sp.nov.。对新种进行详细的描述,并与近似种作了比较。     

甘肃陆生贝类二新种(前鳃亚纲:中腹足目:环口螺科)

1998年4－5月作者在甘肃省南部地区考察,获得陆生贝类标本一批,经鉴定发现2新种,即大河腹皱螺Gastroptychia dahensis sp.nov。和清河倍唇螺Diplommatina qinghensis sp.nov.,隶属于前鳃亚纲,中腹足目,环口螺科,腹皱螺属,倍唇螺属。文中对新种形态特征,栖息环境进行了记述,并与近似种作了比较。     

砂螺属一新种(肺螺亚纲:柄眼目:虹蛹螺科)

作者分别于１９９３年８月８日和１９９４年５月２３日,在云南省获得一批陆生贝类标本;经鉴定发现砂螺属一新种,即石林砂螺Ｇａｓｔｒｏｃｏｐｔａ ｓｈｉｌｉｎｅｎｓｉｓ ｓｐ．ｎｏｖ．,隶属于肺螺亚纲：柄眼目：虹蛹螺科：砂螺属。本文对新种的形态特征、栖息环境进行了记述,并对其近似种进行了讨论。     

中国管螺属的研究(肺螺亚纲:柄眼目:烟管螺科:管螺亚科)

作者系统整理了中国管螺属Ｐｈａｅｄｕｓａ的标本和有关资料,已知我国管螺属计有２２种,其中发现有３新种,即峨嵋管螺Ｐｈａｅｄｕｓａ ｅｍｅｉｅｎｓｉｓ ｓｐ．ｎｏｖ．、丹巴管螺Ｐｈａｅｄｕｓａ ｄａｎｂａｅｎｓｉｓ ｓｐ．ｎｏｖ．和三门管螺Ｐｈａｅｄｕｓａ ｓａｎｍｅｎｅｎｓｉｓ ｓｐ．ｎｏｖ．。本文对旧有的种进行了整理和甄别,对新种的形态特征作了详细的描述,并与近似种进行了比较。     

中国喇叭螺属的研究及六新种记述(肺螺亚纲:柄眼目:虹蛹螺科)

作者整理和记忆了中国科学院动物研究所历年来所保存的中国喇叭螺属的标本,共计有１４种,其中有６新种,即五齿喇叭螺,凤悬喇叭螺,,西山喇叭螺,太白喇叭螺,双片贝喇叭螺,石林贝喇叭螺,文中对中国喇叭螺属的种类进行了整理和鉴别,并对６新种的形态特态,栖息环境进行了记述,对相似种进行了讨论。     

中国陆生贝类二新种（肺螺亚纲：柄眼目：虹蛹螺科）

１９９２年３月至５月,作用在陕西省考察,获得陆生贝类一批,经鉴定发现２新种,即双片喇叭螺Ｂｏｙｓｉｄｉａ ｄｉｌａｍｅｌｌａｒｉｓ ｓｐ．ｎｏｖ．和凤县喇叭螺Ｂｏｙｓｉｄｉａ ｆｅｎｇｘｉａｎｅｎｓｉｓ ｓｐ．ｎｏｖ．,隶于肺螺亚纲、柄眼目、虹蛹螺科、喇叭螺属。文内对２新种形态特征、栖息环境进行地描述,并对其相似种进行了讨论。     

中国云南喇叭螺属一新种(肺螺亚纲,柄眼目,虹蛹螺科)

详细记述了喇叭螺属Boysidia一新种,金平喇叭螺新种Boysidia(Bensonella)jinpingensis sp.nov.。对新种的形态进行了详细描述,并与其近似种进行了对比和讨论。模式标本保存于昆明医科大学细胞生物学与医学遗传学系标本室。     

贵州环口螺科一新种(前鳃亚纲:中腹足目:环口螺科)

1998年7-8月作者在贵州南部地区考察,获得陆生贝类标本一批,经鉴定发现1新种,即茂兰腹皱螺Gastroptychia maolanensis sp.nov。隶属于前鳃亚纲,中腹足目,环口螺科,腹皱螺属。描述了新种形态特征,栖息环境,并对其近似种进行了讨论。     

中国弯螺属一新种记述(肺螺亚纲,柄眼目,扭轴蜗牛科)

2011年8月在云南省泸水县进行陆生贝类调查过程中,于蛮云采集到一些弯螺属个体,经鉴定为中国弯螺属一新种,蛮云弯螺新种Sinoennea manyunensis sp.nov.。弯螺属的种类主要分布于东亚和南亚地区;对新种的形态特征进行了详细描述,并与近似种进行了比较、讨论。模式标本保存在昆明医科大学基础医学院细胞生物学与医学遗传学系。     

Quadruplexes of human telomere DNA analogs designed to contain G:A:G:A,G:G:A:A,and A:A:A:A tetrads

Replacement of two to four guanines by adenines in the human telomere DNA repeat dG₃(TTAG₃)₃ did not hinder the formation of quadruplexes if the substitutions took place in the terminal tetrad bridged by the diagonal loop of the intramolecular antiparallel three‐tetrad scaffold, as proved by CD and PAGE in both Na⁺ and K⁺ solutions. Thermodynamic data showed that, in Na⁺ solution, the dG₃(TTAG₃)₃ quadruplex was destabilized, the least by the two G:A:G:A tetrads, the most by the G:G:A:A tetrad in which the adenosines replaced syn‐guanosines. In physiological K⁺ solution, the highest destabilization was caused by the 4A tetrad. In K⁺, only the unmodified dG₃(TTAG₃)₃ quadruplex rearranged into a K⁺‐dependent quadruplex form, none of the multiple adenine‐modified structures did so. This may imply biological consequences for nonrepaired A‐for‐G mutations. © 2010 Wiley Periodicals, Inc. Biopolymers 93: 880–886, 2010.     

Oka: Behind the Barricades: Kanehsatake: 270 Years of Resistance: Spudwrench: Kahnawake Man: My Name is Kahentiiosta: Acts of Defiance

Oka: Behind the Barricades. 1998. 312 minutes. For more information contact the National Film Board of Canada, 3155 Côte de Lisse Rd., St. Laurent, Quebec H4N 2N4. Series of four videos:
Kanehsatake: 270 Years of Resistance. 1993. 120 minutes. Directed by Alanis Obomsawin .
Spudwrench: Kahnawake Man. 1997. 58 minutes. Directed by Alanis Obomsawin .
My Name is Kahentiiosta. 1995. 30 minutes. Directed by Alanis Obomsawin .
Acts of Defiance. 1992. 104 minutes. Directed by Alec MacLeod .     

A dimeric RNA quadruplex architecture comprised of two G:G(:A):G:G(:A) hexads,G:G:G:G tetrads and UUUU loops

Using CD and NMR, we determined the structure of an RNA oligomer, r(GGAGGUUUUGGAGG) (R14), comprising two GGAGG segments joined by a UUUU segment. A modified quadruplex structure was observed for r(GGAGGUUUUGGAGG) in solution even in the absence of K(+). An unusually stable dimeric RNA quadruplex architecture formed from two strands of r(GGAGGUUUUGGAGG) at low K(+) concentration is reported here. In each strand of r(GGAGGUUUUGGAGG), two sets of successive turns in the GGAGG segments and turns at both ends of the UUUU loops drive four G-G steps to align in a parallel manner, a core with two stacked G-tetrads being formed. Two adenine bases bind to two edges of one G:G:G:G tetrad through the sheared G:A mismatch augmenting the tetrad into a G:G(:A):G:G(:A) hexad. Thus, one molecule of r(GGAGGUUUUGGAGG) folds into a modified quadruplex comprising a G:G:G:G tetrad, a UUUU double-chain reversal loop and a G:G(:A):G:G(:A) hexad. Two such molecules further associate by stacking through the dimeric hexad-hexad interface with a rotational symmetry. The ribose rings of most nucleotides take S (close to C2'-endo) puckering, which is unusual for an RNA. K(+) can increase the stability of this quadruplex structure; the number of bound K(+) was estimated from the results of the titration experiment. Besides G:G and G:A mismatches, a network of hydrogen bonds including O4'-NH(2) and C-H..O hydrogen bonds, and the extensive base stacking contribute to the high thermodynamic stability of R14. Our results could provide the stereochemical and thermodynamic basis for elucidating the biological role of the GGAGG-containing RNA segments abundantly existing in various RNAs. Relevance to quadruplex-mediated mRNA-FMRP binding and HIV-1 genome RNA dimerization is discussed.     

Experimental demonstration of T:(G:G:G:G):T hexad and T:A:A:T tetrad alignments within a DNA quadruplex stem

A template-based approach was used to design unprecedented architectural motifs into a known DNA framework. The structure formed by the sequence d(GCGGTTGGAT) in 0.1 M Na(+) solution has been determined using molecular dynamics simulations constrained by distance and dihedral restraints derived from NMR experiments. The molecular topology has been previously observed for the sequence d(GCGGTGGAT) (Webba da Silva, M. (2003) Biochemistry 42, 14356-65). Insertion of a single thymine into the double chain reversal formed by the segment GGTGG results in the unprecedented experimental demonstration of a T:(G:G:G:G):T hexad. The bi-stranded hexad results from the pairing alignment of two G(T-G) triads. Each triad results from recognition of the sheared edge of a guanine by the Watson-Crick edge of a thymine of the segment GGTTGG. The alignment is stabilized by base-stacking of the thymine to the sugar pucker of the preceding thymine. The latter is involved in formation of the T:A:A:T tetrad alignment by forming a hydrogen bond with the free amino proton of a Watson-Crick aligned A:A mispair. We have thus established that residues in double chain reversal loops linking juxtaposed tetrads of a quadruplex stem may facilitate formation of yet unknown hydrogen bond alignments. By employing a systematic approach analysis of sequence motifs appearing in double chain reversals, bridging tetrad layers should allow for the prediction of topologies and architectural motifs appearing in biologically relevant genomic regions.     

Focus: Rare Disease: Chronic Pulmonary Aspergillosis: A Brief Review

Chronic Pulmonary Aspergillosis (CPA) is a destructive pulmonary disease caused by a fungal infection, affecting mainly individuals with prior or concurrent pulmonary conditions. It has a global prevalence of 42 per 100,000 population, but in the US and Europe, prevalence is less than 1 per 100,000. The clinical definition of CPA is based on various factors accounting for comorbidities, clinical presentation, and duration. It may be categorized into five subtypes that the disease may evolve between over time. Based on global consensus covering the spectrum of low-resource to high-resource settings, diagnosis is a multi-factorial process that involves a combination of clinical presentation persisting over 3 months, radiological findings, positive culture growth, and serological tests. CPA remains underdiagnosed due to a lack of awareness and is often misdiagnosed due to the comorbidities present. Treatment options are limited due to a lack of research. Furthermore, associated comorbidities and drug interactions further complicate treatment plans. Follow-up throughout treatment should be based on understanding the predictors of mortality. Identification of potential relapse or resistance to antifungal therapy is crucial to limit the low long-term survival rate. Awareness surrounding this devastating disease needs to be raised further to enable earlier identification, improve understanding of patient factors associated with prognosis, and the future potential for targeted therapies. This review aims to raise awareness of this rare condition among practitioners, by providing an overview of common risk factors influencing the prevalence and incidence of the disease. We further discuss current approaches and recent advancements in CPA diagnosis and treatment.     

Hormone interactions and regulation of PsPK2::GUS compared with DR5::GUS and PID::GUS in Arabidopsis thaliana

The putative pea PINOID homolog, PsPK2, is expressed in all growing plant parts and is positively regulated by auxin, gibberellin, and cytokinin. Here, we studied hormonal regulation of PsPK2::GUS expression compared with DR5::GUS and PID::GUS in Arabidopsis. PsPK2::GUS, DR5::GUS, and PID::GUS expression in Arabidopsis shoots is mainly localized in the stipules, hydathodes, veins, developing leaves, and cotyledons. Unlike DR5::GUS, PsPK2::GUS, and PID::GUS are weakly expressed in root tips. Both DR5::GUS and PsPK2::GUS are induced by different auxins and are more sensitive to methyl indole acetic acid, 4-chloro-indole acetic acid, and α-naphthalene acetic acid than others. GA(3) has no significant effect on GUS activity in DR5::GUS-transformed seedlings compared to the control, but induction by auxin and gibberellin in combination is synergistic. Cytokinin increases auxin transport in Arabidopsis seedlings. Auxin, gibberellin, and cytokinin all increase GUS activity in shoots of PsPK2::GUS transformed plants compared to the control. However, only auxin and gibberellin increase GUS activity in PID::GUS shoots. In conclusion, auxin, gibberellin, and cytokinin positively regulate PsPK2 expression in shoots, but not in roots. Auxin and gibberellin also upregulate AtPIN1 and LEAFY expression, which is similar to PsPIN1 and Uni in pea. With minor exceptions, the orthologous genes from both species are regulated similarly.     

Focus: Microbiome: Metagenomic Assembly: Overview,Challenges and Applications

Advances in sequencing technologies have led to the increased use of high throughput sequencing in characterizing the microbial communities associated with our bodies and our environment. Critical to the analysis of the resulting data are sequence assembly algorithms able to reconstruct genes and organisms from complex mixtures. Metagenomic assembly involves new computational challenges due to the specific characteristics of the metagenomic data. In this survey, we focus on major algorithmic approaches for genome and metagenome assembly, and discuss the new challenges and opportunities afforded by this new field. We also review several applications of metagenome assembly in addressing interesting biological problems.     

Review: Gastric cancer: Basic aspects

Gastric cancer is still one of the most prevalent and deadliest cancers in the world. Although our knowledge about the disease has progressed extraordinarily, this has not been accompanied by our capacity to effectively treat the disease. In the last years, immunotherapy made its way into the cancer field and was responsible for major changes in the treatment success rates for several cancer types. Although gastric cancer was not among the first successful targets of this type of therapy, the relationship between this type of cancer, immunosurveillance and immunotherapy is now being actively researched. In this article, we review the literature of the past year regarding the relationship between gastric cancer, its immune microenvironment and response to immunotherapy. Published data indicate that the immune microenvironment influences the clinical behaviour of gastric cancer, and is correlated with its histologic and molecular subtypes with an emphasis on the microsatellite‐ and EBV‐positive tumour subgroups. Although the literature regarding response to immunotherapy is scarce, there is good evidence that patient stratification for immunotherapy is going to become a reality in gastric cancer.     

Retinol and retinyl esters: biochemistry and physiology: Thematic Review Series: Fat-Soluble Vitamins: Vitamin A

By definition, a vitamin is a substance that must be obtained regularly from the diet. Vitamin A must be acquired from the diet, but unlike most vitamins, it can also be stored within the body in relatively high levels. For humans living in developed nations or animals living in present-day vivariums, stored vitamin A concentrations can become relatively high, reaching levels that can protect against the adverse effects of insufficient vitamin A dietary intake for six months, or even much longer. The ability to accumulate vitamin A stores lessens the need for routinely consuming vitamin A in the diet, and this provides a selective advantage to the organism. The molecular processes that underlie this selective advantage include efficient mechanisms to acquire vitamin A from the diet, efficient and overlapping mechanisms for the transport of vitamin A in the circulation, a specific mechanism allowing for vitamin A storage, and a mechanism for mobilizing vitamin A from these stores in response to tissue needs. These processes are considered in this review.