On the definition, nomenclature and classification of water channel proteins (aquaporins and relatives)

A water channel protein (WCP) or a water channel can be defined as a transmembrane protein that has a specific three-dimensional structure with a pore that provides a pathway for water permeation across biological membranes. The pore is formed by two highly conserved regions in the amino acid sequence, called NPA boxes (or motifs) with three amino acid residues (asparagine-proline-alanine, NPA) and several surrounding amino acids. The NPA boxes have been called the "signature" sequence of WCPs. WCPs are a family of proteins belonging to the Membrane Intrinsic Proteins (MIPs) superfamily. In addition, in the MIP superfamily (with more than 1000 members) there are also proteins with no channel activity. The WCP family include three subfamilies: aquaporins, aquaglyceroporins and S-aquaporins. (1) The aquaporins (AQPs) are water selective or specific water channels, also named by various authors as "orthodox", "ordinary", "conventional", "classical", "pure", "normal", or "sensu strictu" aquaporins); (2) The aquaglyceroporins are permeable to water, but also to other small uncharged molecules, in particular glycerol; this family includes the glycerol facilitators, abbreviated as GlpFs, from glycerol permease facilitators. The "signature" sequence for aquaglyceroporins is the aspartic acid residue (D) in the second NPA box. (3) The third subfamily of WCPs have little conserved amino acid sequences around the NPA boxes, unclassifiable to the first two subfamilies. I recommend to use always for this subfamily the name S-aquaporins. They are also named "superaquaporins", "aquaporins with unusual (or deviated) NPA boxes", "subcellular aquaporins", or "sip-like aquaporins". I also recommend to use always the spelling aquaporin (not aquaporine), and, for various AQPs, the abbreviation AQP followed immediately by the number, (e.g. AQP1), with no space or - which might create confusions with "minus".     

Making Decisions on the Resources for Cancer Control

We aim at modelling the strategic decision making process in case of devoting resources to a governmental cancer control program. We use a model based on the theory of Analytic Hierarchy Process. In this article we describe the characteristic features of such a decision making process and reveal the complexity of the problem underlying the decisions. A second article will present and discuss the results from the application of the AHP model. Interventions which are capable of decreasing the burden of cancer in a society need strategic approach. Decisions on interventions seem inevitable to be based on and balance between the priorities and the available resources. There is not much doubt about it that the reason for setting the priorities arises on the one hand from the scarcity of resources. On the other hand, priorities evolve on other bases, and are supposed to "guide" health policy makers devoting the scarce resources. In general, a strategic mode of thought has been based on assumptions, which, in case of cancer control enhance the necessity to assess information on cancer and cancer patients, and to understand the factors contributing towards better health. The capabilities of the NCCP achieving its aims by preventing the development of cancer diseases (primary prevention), by making use of the means of early detection and appropriate therapy (secondary prevention), and by providing modern (comprehensive) tertiary prevention are inevitably affected by the priorities. Health policy should assume a responsibility for enforcing certain priorities and should be aware of the long-term interest of the population. To solve the problem we restrict the model to a simple three level one, representing the goals, the criteria, and the alternatives of the resource allocation. We determine "decreasing the burden of cancer" as the overall goal. "Distributive justice" "cost-effectiveness", "human rights", "evidences", and "standpoints of a community" serve as criteria, while "primary prevention", "early detection and therapy, both belonging to the secondary prevention", "tertiary prevention", "research", and "education" form the alternatives.     

卵壳的超微结构特征

本文运用扫描电镜研究了美洲鸵鸟,鹂鹋,非洲鸵鸟,普通家鸡,环颈雉,绿头鸭,王企鹅等七种现生鸟蛋壳和更新世安氏鸵鸟蛋壳以及六种白垩纪恐龙蛋壳（长形长形蛋Ｅｌｏｎｇａｔｏｏｌｉｔｈｕｓｅｌｏｎｇａｔｕｓ,安氏长形蛋Ｅｌｏｎｇａｔｏｏｌｉｔｈｕｓａｎｄｒｅｗｓｉ,瑶屯巨形蛋Ｍａｃｒｏｏｌｉｔｈｕｓｙａｏｔｕｎｅｎｓｉｓ粗皮巨形蛋Ｍａｃｒｏｏｌｉｔｈｕｓｒｕｇｕｓｔｕｓ,将军顶圆形蛋Ｓｐｈｅｒｏｏｌｉｔｈ     

Brefeldin A action and recovery in Chlamydomonas are rapid and involve fusion and fission of Golgi cisternae

CHLAMYDOMONAS NOCTIGAMA has a non-motile Golgi apparatus consisting of several Golgi stacks adjacent to transitional ER. These domains are characterized by vesicle-budding profiles and the lack of ribosomes on the side of the ER proximal to the Golgi stacks. Immunogold labelling confirms the presence of COPI-proteins at the periphery of the Golgi stacks, and COPII-proteins at the ER-Golgi interface. After addition of BFA (10 microg/ml) a marked increase in the number of vesicular profiles lying between the ER and the Golgi stacks is seen. Serial sections of cells do not provide any evidence for the existence of tubular connections between the ER and the Golgi stacks, supporting the notion that COPI- but not COPII-vesicle production is affected by BFA. The fusion of COPII-vesicles at the CIS-Golgi apparatus apparently requires the presence of retrograde COPI-vesicles. After 15 min the cisternae of neighbouring Golgi stacks begin to fuse forming "mega-Golgis", which gradually curl before fragmenting into clusters of vesicles and tubules. These are surrounded by the transitional ER on which vesicle-budding profiles are still occasionally visible. Golgi remnants continue to survive for several hours and do not completely disappear. Washing out BFA leads to a very rapid reassembly of Golgi cisternae. At first, clusters of vesicles are seen adjacent to transitional ER, then "mini Golgis" are seen whose cisternae grow in length and number to produce "mega Golgis". These structures then divide by vertical fission to produce Golgi stacks of normal size and morphology roughly 60 min after drug wash-out.     

Usefulness of amplitude as a rheographic-cardiographic parameter for evaluation of degree of heart failure]

Impedance rheographic-cardiography has been performed in 40 patients with chronic congestive heart failure. At the same time, polycardiographic data have been recorded and used for the correlative analysis. A curve dZ/dt has been analysed and "S", "X", "A", "O" waves amplitudes together with A/S and X/S ratios have been calculated, depending on the degree of heart failure. It was found, that rheographic-cardiography may be valuable technique for the assessment of the degree of heart failure. Curve dZ/dt in patients with more advanced heart failure is of hypodynamic character (decrease in "S", "X", and "A" waves amplitude with an increase in "O" wave amplitude), being similar to sinusoidal curve. The most valuable rheographic-cardiograph parameters enabling the assessment of heart failure are: "S" and "O" waves amplitudes, and A/S and X/S ratios. Correlative analysis has also shown several important relationships between rheographic-cardiographic and polycardiographic parameters, which may facilitate the assessment of heart failure.     

蝉的变音调复合声和发声机制的分析

蛙鸣蝉(Meimuna opalifera (Walk).ab.punctata Kato)的自然鸣声为“ji…guái”的重复单变调复合声.“ji”为主音频约4800Hz的准单音;“guái”的波形和主音频呈明显的演变,优势主频约2100Hz和2800Hz的变音调声.鸟鸣蝉(Meimuna opalifera (Walk)var.formosana Kato)的自然鸣声由重复的“jiū…ruǎ”和“jiū…gū…”合成的双变调复合声.“jiū”为基频和主频分别约625Hz和2100—2300Hz的准单音;“ruǎ”的波形和主音频呈明显的演变,基音和优势主频分别约575—625Hz和1550—1750Hz的变音调声.“gū”为优势主频约625Hz的准单音.变音调复合声不仅与腹部运动有关,而主要取决于发声肌的收缩特性和发声膜肋结构的振动特性.     

Polymorphism of acetylcholinesterase and identification of new molecular forms after sedimentation analysis

Acetylcholinesterase (AChE) is composed of several distinct molecular forms, which are identified and partly resolved by velocity sedimentation analysis on sucrose gradients. We made the assumption that each AChE form sediments as a peak of activity with a gaussian shape in the continuous sucrose gradient. We experimentally demonstrate that the complex AChE profiles can be decomposed in gaussian distributions of separate molecular entities. We performed a high salt-detergent extraction of AChE from mouse skeletal muscle and isolated fractions enriched in each particular from. These fractions were then submitted to a second sedimentation, to assess the stability and to further characterize each AChE form. Then, we calculated the statistical significance level of each AChE form and identified up to 9 separate molecular specifies in mouse adult muscle. These forms are the major "4 S", "6.5 S", "10 S", "12 S" and "16 S" and minor molecular active components of AChE. These results suggest complex structural interactions between catalytic and non catalytic subunits of AChE and do not simply fit the tailed asymmetric globular model of AChE with six molecular species.     

杨属植物化学成分和药理作用的研究进展

本文对杨属植物的化学成分和药理作用作了全面、系统的综述,为杨属植物药用价值的开发利用提供了科学的依据.     

A noneuclidean Volvox, or why it is better not to teach Volvox in the course on zoology

Empty "spheroid" of Volvox is compared with biomorph "thread", "disk" and solid "sphere" using such characteristics as topological dimensionality, average distance between cells, mutual remoteness of inner and surface cells, contiguity of cells. It is usually supposed that these parameters are significant for physiological gradients that determine cell specialization. One-dimensional "thread" has the longest physiological communications between cells and the average degree of contiguity about 2 (each cell contacts two neighbors). Biological morph "disk" has a degree about 6, two-side frontal physiological gradient inside the cell, and less expressed inter-cell gradient. Biomorph designated as 3-dimensional solid "sphere" has a degree of contiguity about 12-24, strong radial inter-cell gradient (non-equal conditions for surface and inner layers) and short distances between cells. These parameters favor cell specialization and their integration in multicellular organism. The "sphere" corresponds to hypothetical ancestor of Metazoa - "Metschnikoff's Phagocytella", while the "disk" - to "Placula of Bütschli". Biomorph "spheroid" of Volvox has a degree of contiguity about 6 and continuous tangential inter-cell gradient on noneuclidean surface. Radial gradient is absent here. Due to noneuclidean nature of "spheroid" the distances between cells are longer here than in case of "disc" and "sphere". All cells are under the same conditions for specialization and multiple primary integration. The secondary integration in higher Volvocales (differentiation in somatic and generative hemispheres) was probably caused by directed movement of the whole colony. Specialization of cells in lower invertebrates develops in a way which is characteristic for biomorph "sphere" on the basis of 3-dimensionality. The differentiation of animal and vegetal poles is connected with gastrulation (but not with directed movement as in case of Volvox). Gastrulation through invagination does not comparable with inversion of plate-like embryo of Volvox into "spheroid". Invagination is the transformation of a "bent of sphere", whereas the inversion is the "bent of plate". Independently of particular mechanism gastrulation results in 3-dimensionality (as in case of "sphere"). However the integration of cells in Volvox is explained by special peculiarities of 2-dimensional noneuclidean surface. That's why Volvox cannot be considered as model of ancestor of Metazoa.     

几种萝卜提取物在组织培养细胞中的抗病毒感染活性

我们曾报道,白萝卜提取物是一种干扰素诱生剂,对致死性病毒感染动物有很显著的保护作用。 本实验在组织培养单层细胞上测试了十字花科萝卜属几种萝卜栽培变种,包括“心里美”、“卫青”、“象牙白”(白萝卜)和伞形科胡萝卜提取物的抗病毒感染活性。 萝卜提取物的制备和定量方法,按文献进行。萝卜提取物在组织培养单层细胞上抑     

The making of symbiont capsule in the plataspid stinkbug Megacopta punctatissima

In stinkbugs of the family Plataspidae, adult females deposit small brownish particles, containing specific symbiotic bacteria inside, on the underside of their egg mass. Newborn nymphs ingest the content of the unique structure, called "symbiont capsule", whereby vertical transmission of the symbiont occurs. We investigated the fine structure and the formation process of the symbiont capsule in the Japanese common plataspid stinkbug, Megacopta punctatissima, by using light and electron microscopy. It was demonstrated that (i) the capsule consists of three structural components, namely "symbionts", "matrix" and "envelope"; (ii) the posterior midgut of adult females is characterized by several specific sections with peculiar anatomical traits, including "thin crypt-bearing midgut (TCM) section", "swollen crypt-bearing midgut (SCM) section" and "brownish enlarged midgut (BEM) end section"; (iii) the different capsule components, symbionts, matrix and envelope, are produced and/or supplied by the specialized midgut sections, TCM, SCM and BEM, respectively; and (iv) the capsule components are stored in BEM and excreted during oviposition to produce the symbiont capsules. These results strongly suggested that the host insect incurs a substantial cost for the symbiont transmission. Ecological and evolutionary implications of the highly developed, female-specific system for symbiont transmission were discussed.     

论害虫种群的生态控制

本文根据保护生物圈与经济持续发展的要求,提出害虫种群的“生态控制’对策,以代替现在国内外采用的“综合防治”。文中根据生态学与经济学理论,不仅提出了“生态控制”应遵循的经济学与生态学的管理原则,并且提出了“生态控制”的指导思想与方法论,以及它的目标函数、约束条件与主要对策。进而根据国内外本领域的科技发展动态分析与生产实际需要,论述了本种对策在生产中的可行性与重要性。     

Genomic ancestry, self-reported "color" and quantitative measures of skin pigmentation in Brazilian admixed siblings

A current concern in genetic epidemiology studies in admixed populations is that population stratification can lead to spurious results. The Brazilian census classifies individuals according to self-reported "color", but several studies have demonstrated that stratifying according to "color" is not a useful strategy to control for population structure, due to the dissociation between self-reported "color" and genomic ancestry. We report the results of a study in a group of Brazilian siblings in which we measured skin pigmentation using a reflectometer, and estimated genomic ancestry using 21 Ancestry Informative Markers (AIMs). Self-reported "color", according to the Brazilian census, was also available for each participant. This made it possible to evaluate the relationship between self-reported "color" and skin pigmentation, self-reported "color" and genomic ancestry, and skin pigmentation and genomic ancestry. We observed that, although there were significant differences between the three "color" groups in genomic ancestry and skin pigmentation, there was considerable dispersion within each group and substantial overlap between groups. We also saw that there was no good agreement between the "color" categories reported by each member of the sibling pair: 30 out of 86 sibling pairs reported different "color", and in some cases, the sibling reporting the darker "color" category had lighter skin pigmentation. Socioeconomic status was significantly associated with self-reported "color" and genomic ancestry in this sample. This and other studies show that subjective classifications based on self-reported "color", such as the one that is used in the Brazilian census, are inadequate to describe the population structure present in recently admixed populations. Finally, we observed that one of the AIMs included in the panel (rs1426654), which is located in the known pigmentation gene SLC24A5, was strongly associated with skin pigmentation in this sample.     

Impact of Firm-Based Environmental Standards on Subsidiaries and Their Suppliers: Evidence from Motorola-Penang

How successful are multinational corporations in extending their firm-based environmental standards to their subsidiaries and those subsidiaries' local suppliers in their global production networks in developing countries? We address this question through an in-depth case study of how Motorola, a prominent multinational electronics firm with an extensive global production network, is using a set of firm-based standards to meet several new stringent European Union environmental directives. The case study demonstrates that these firm-based standards appear to be enabling a major subsidiary and its suppliers in one developing economy to reduce the environmental intensities of their production activities. This finding suggests that the firm-based environmental standards of multinationals with extensive global production networks might contribute to a leveling up of environmental standards in subsidiaries and their local suppliers, rather than a "race to the bottom", thus reinforcing the technique or intensity effects associated with open trade, investment, and technology policies.     

A review of clinical and experimental observations about antidepressant actions and side effects produced by Hypericum perforatum extracts

Hypericum perforatum is an herbaceous perennial plant, also known as "St. John's wort", used popularly as a natural antidepressant. Although some clinical and experimental studies suggest it has some properties similar to conventional antidepressants, the proposed mechanism of action seems to be multiple: a non-selective blockade of the reuptake of serotonin, noradrenaline and dopamine; an increase in density of serotonergic and dopaminergic receptors and an increased affinity for GABAergic receptors; moreover, the inhibition of monoaminoxidase enzyme activity has been involved. In any case, the increase of monoamine concentrations in the synaptic cleft resembles several actions exerted by clinically effective antidepressants. In the present article, we review some of the controversial evidence derived from clinical and experimental studies suggesting that H. perforatum exerts antidepressant-like actions, and we also review some of its side effects, such as nausea, rash, fatigue, restlessness, photosensitivity, acute neuropathy, and even episodes of mania and serotonergic syndrome when administered simultaneously with other antidepressant drugs. All of the foregoing suggests that H. perforatum extracts appear to exert potentially significant pharmacological activity involving several neurotransmission systems supposed to be involved in the pathophysiology of depression. However, little information regarding the safety of H. perforatum is available, including potential herb-drug interactions. There is a need for additional research on the pharmacological and biochemical activity of H. perforatum, as well as its side-effects and its several bioactive constituents to further elucidate the mechanisms of antidepressant actions.     

Mutagenic specificity of ultraviolet light

Genetic and sequencing studies of ultraviolet light (u.v.)-induced mutations in the lacI gene of Escherichia coli show the following: u.v. stimulates many types of mutations. In lacI, base substitutions account for 60 to 65% of the observed mutations, small frameshifts 30 to 35%, and deletions of more than several base-pairs approximately 5%. A comparison of the mutational spectrum of u.v.-induced mutations with those of other SOS-dependent mutagens and with the mutations produced by inducing the SOS system in the absence of mutagenic treatment indicates that most u.v.-induced base substitutions are "targeted", resulting from premutational lesions across from the site of the mutations. Among base substitutions, both transitions and transversions occur, although the most favored mutational sites involve G X C----A X T transitions. G X C----A X T transitions are induced preferentially at sites of adjacent pyrimidines. In one case the conversion of a site from -A-C-A- to -T-C-A- results in a 15-fold increase in u.v.-induced C----T transitions. Frameshifts at certain sites are well-induced by u.v., and the largest hotspot in the I gene involves the loss of an (sequence in text) base pair from a (sequence in text) sequence. Of 25 frameshifts detected by DNA sequencing, 23 mutations at seven different sites result from the elimination of a single base-pair, and two mutations result from the elimination of two base-pairs. No additions were detected. The use of a lacI-Z fusion system, which allows direct selection of frameshifts of either sign, reveals that throughout the entire gene frameshifts that eliminate a single base-pair (-1) predominate by a factor of 20 or more over frameshifts that add a single base-pair (+1). In one case a two-base-pair elimination occurs frequently, resulting in the loss of a -C-T- sequence (on one strand), or a -T-C- sequence, from a -C-T-C-T-C-T-C- sequence. For both frameshifts and base substitutions, some aspect of the larger surrounding sequence beyond the nearest neighbors can influence mutation rates by as much as 50-fold, thus determining which sites are seen as hotspots. The bearing of these and other data on the detailed mechanism of mutagenesis is considered in the Discussion.     

中华猕猴桃雄性株系"磨山4号"的选育研究

通过对近年来选育的“磨山４号”、“磨山５号”、“武植８２－１２”、“武植８０－４”、“武植８２－５”等５个中华猕猴桃（ＡｃｔｉｎｉｄｉａｃｈｉｎｅｎｓｉｓＰｌａｎｃｈ）雄性株系的花期、花量、花粉生活力、花粉量的观察,并分析与“武植３号”授粉对果实的影响,从综合性状来看,“磨山４号”花期比一般雄株长２个星期左右（约２０天）,有效花粉量高,株型紧凑,授粉后的果实单果重及Ｖｃ的含量均高于其它雄株,为中华猕猴桃适配雄株。     

马铃薯'转心乌'块茎色素的组成和含量

马铃薯转心乌块茎的内、外韧皮部和髓为淡黄色,周皮和木质部为紫色;木质部的紫色形成一个不规则的环",并向内韧皮部蔓延.系列特征颜色反应和紫外可见光谱分析表明:‘转心乌’块茎紫色素属于黄酮类化合物,可能含有酚性邻位二羟基,并被肉桂酸酰化,不含类胡萝卜素、查耳酮、噢哢、异黄酮、儿茶素;花色苷和/或其苷元花色素奠定了‘转心乌’块茎着色的基础,其它的非红色的黄酮类化合物发挥共色素的作用.块茎的皮"紫色最浓","环"其次,"肉"最淡,这与"皮"、"环"和"肉"的色价、花色苷含量和总黄酮类化合物含量的变化趋势呈正相关.     

First steps of otolith formation of the zebrafish: role of glycogen?

The first steps of otolith formation were studied by electron microscopy in zebrafish embryos at different postfertilization (PF) time intervals. Between 19 and 22 h PF, the otic cavity contains glycogen particles derived by an apocrine process from the apical portions of the epithelial cells of the inner ear. The particles are arranged in parallel arrays, then in pseudocrystalloid structures, and finally in concentric arrays to form dense clusters referred to as "spherules". At 23 h PF, a group of "globules", consisting of modified aggregated "spherules" surrounded by several free "spherules", forms the nascent otolith. At 30 h PF, fused globules form a roughly spherical otolith. Spherules undergoing their process of modification and aggregation, are located in its central part, and constitute the so-called "nucleus". At 50 h PF, the otolith is a flattened hemisphere. It is made up of fused globules surrounded by two concentric layers whose organization is similar to that observed in the otolith of the adult fish. At this stage, calcium may be detected in the otolith except in its nucleus. We suggest that glycogen molecules found in the nascent otolith might allow the insertion of molecules such as glycoproteins (collagens) which are known to fix calcium. As a result, glycogen might play a key role in initiating the formation of otoliths and possibly that of other calcified tissues.