Phagocytosis of chloramine B sensitive and resistant staphylococci isolated from healthy persons and patients

Phagocytic reaction with respect to antibiotic and chloramine B sensitive and resistant staphylococci isolated from healthy persons and patients, air and stock of medical institutions was studied on albino mice. It was shown that the staphylococcal isolates included strains simultaneously sensitive to antibiotics and chloramine, sensitive to antibiotics and resistant to chloramine, resistant to antibiotics and sensitive to chloramine and simultaneously resistant to antibiotics and chloramine. Activity, intensity and completeness of phagocytosis by leucocytes from mouse abdominal cavity exudates with respect to the staphylococcal strains sensitive to antibiotics and resistant to chloramine, resistant to antibiotics and sensitive to chloramine and simultaneously resistant to antibiotics and chloramine were lower than the values of the phagocytic reaction with respect to the isolates simultaneously sensitive to antibiotics and chloramine. This suggested that not only antibiotic resistance of microbes but also their resistance to disinfectants could be referred to complicating factors of hospital infections.     

Lay concepts in informed consent to biomedical research: the capacity to understand and appreciate risk

Persons generally must give their informed consent to participate in research. To provide informed consent persons must be given information regarding the study in simple, lay language. Consent must be voluntary, and persons giving consent must be legally competent to consent and possess the capacity to understand and appreciate the information. This paper examines the relationship between the obligation to disclose information regarding risks and the requirement that persons have the capacity to understand and appreciate the information. There has been insufficient attention to the extent to which persons must be able to understand and appreciate study information in order to have their consent deemed valid when the information is provided in simple, lay language. This paper argues that (1) the capacity to understand and appreciate information that should be deemed necessary to give valid consent should be defined by the capacity of the typical, cognitively normal adult and (2) the capacity of the typical, cognitively normal adult to understand and appreciate the concept of risk is limited. Therefore, (3) all things being equal, potential subjects must possess a limited capacity to understand and appreciate risk to be deemed competent to consent to research participation. (4) In some cases investigators ought to require that persons possess a greater than typical capacity to understand and appreciate risk.     

What conservationists need to know about farming

Farming is the basis of our civilization yet is more damaging to wild nature than any other sector of human activity. Here, we propose that in order to limit its impact into the future, conservation researchers and practitioners need to address several big topics--about the scale of future demand, about which crops and livestock to study, about whether low-yield or high-yield farming has the potential to be least harmful to nature, about the environmental performance of new and existing farming methods, and about the measures needed to enable promising approaches and techniques to deliver on their potential. Tackling these issues requires conservationists to explore the many consequences that decisions about agriculture have beyond the farm, to think broadly and imaginatively about the scale and scope of what is required to halt biodiversity loss, and to be brave enough to test and when necessary support counterintuitive measures.     

激光采血的分析研究

本文根据激光与皮肤组织的作用规律对紫外激光,可见激光和红外激光的采血效果进行了系统地分析研究,研究结果表明：CO2激光与Er:YAG激光是采血的理想工具。并对红外激光采血的参娄进行了定量地分析与计算,为激光采血设备的研制和应用提供一个参考。     

Localization of Escherichia coli RNA polymerase binding sites on bacteriophage S13 and 0X174 DNAs by electron microscopy.

Complexes between Escherichia coli RNA polymerase and bacteriophage S13 and phage phiX174 replicative form III DNAs have been shown to form at specific locations on the phage genomes. The major locations on S13 have been mapped at 8 to 10 and 92 to 96% of the genome length, starting from the unique Pst I cleavage site. The locations correspond to the beginnings of genes D and B, respectively. Four minor locations map at 18 to 22, 28 to 32, 50 to 56, and 70 to 74% of the genome. The 70 to 74% site corresponds to the beginning of the A gene. The major locations on phiX174 are at 8 to 10, 50 to 54, and 92 to 94% of the genome. The 50 to 54% site is at the start of the H gene and has an equivalent minor site on S13, but it is not a promoter site. Three minor sites on phiX174, at 20 to 24, 26 to 32, and 68 to 74% of the genome, correspond to sites on S13. The data confirm the locations of sites identified by restriction fragment binding experiments (E. Rassart and J. H. Spencer, J. Virol. 27:677--687, 1978) and the assignment of putative promoters at the start of genes A, B and D.     

Specificity of the binding of trifluoperazine to the calcium-dependent activator of phosphodiesterase and to a series of other calcium-binding proteins

Trifluoperazine inhibits the activation of phosphodiesterase by binding to the calcium-dependent activator. To determine further the specificity by which trifluoperazine binds to activator, we compared the binding of trifluoperazine to activator prepared from several species and tissues and to a number of other calcium-binding proteins devoid of activator activity.Trifluoperazine binds to activator prepared from human, bovine, rat and rabbit brain and from chick embryo fibroblasts. In each case, the binding of trifluoperazine to activator was qualitatively similar and related quantitatively to the ability of the preparation to activate phosphodiesterase.Of the other calcium-binding proteins examined, namely, troponin-C, S-100 protein, phospholipase A, phospholipase B and myosin light chain, only troponin-C displayed any significant calcium-specific binding of trifluoperazine. The binding to troponin-C, however, appeared to be different from the binding to activator; whereas the binding of trifluoperazine to actovator showed no cooperativity, the binding to troponin-C showed positive cooperatively.These results and earlier data showing that trifluoperazine fails to bind to a variety of other proteins, indicate that the binding of trifluoperazine to the calcium-dependent activator of phosphodiesterase is selective and suggest that this binding may explain some of the biochemical and pharmacological actions of this antipsychotic agent.     

西双版纳热带雨林蚁科昆虫区系分析

在西双版纳热带雨林已鉴定蚊科昆虫９亚科７６属２６７种。西双版纳地区的蚂蚁区系以热带至亚热带分布的东洋界成分最为丰富。在属级水平上,与马来西亚界关系最为密切。与澳洲界关系较密切;与非洲界和马拉加西界的关系知中。与新北界,新热带界和古北界的关系最为疏远。可见西双版纳的蚂蚁区系具有典型的热带亚洲起源特征,同时与澳洲和非洲的热带区系有一定的渊源关系。     

Pure acceleration is the primary determinant of speed to first-base in major-league baseball game situations

The purposes of this research were to (a) quantify interval sprint times between Home-Plate and the Foul-Line and the Foul-Line and First-Base, (b) determine if differences exist in interval velocities and acceleration between left- and right-handed batters or between-position groupings, and (c) to quantify determinants of time to First-Base in Major-League Baseball players during actual games. A total of 1,896 sprint times to the Foul-Line (13.7 m) and First-Base (27.4 m) were recorded in 302 baseball players by a single coach, positioned in the dugout with a hand-held stopwatch. Interval velocities and accelerations were computed between Home-Plate and the Foul-Line and the Foul-Line and First-Base; average velocity and acceleration were also determined over the entire 27.4 m. Velocity and acceleration for left-handed batters were greater than for right-handed batters from Home-Plate to the Foul-Line and from Home-Plate to First-Base; however, there were no differences in velocity or acceleration from the Foul-Line to First-Base. Interval velocity was significantly greater for outfielders and infielders compared with that for catchers from Home-Plate to the Foul-Line and from the Home-Plate to First-Base. Outfielders were faster than catchers from the Foul-Line to First-Base; no other between-group differences were evident. Accelerations from Home-Plate to the Foul-Line and from Home-Plate to First-Base were greater for outfielders compared with infielders and catchers. Infielders accelerated at greater rates than did catchers between these intervals. There were no between-position differences in acceleration from the Foul-Line to First-Base. These data indicate that time to First-Base is most affected by acceleration from Home-Plate to the Foul-Line. Coaches should implement strategies that encourage players to sprint maximally over the first 13.7 m to maximize chances of successfully reaching First-Base.     

Interspecific Variability in Sensitivity to UV Radiation and Subsequent Recovery in Selected Isolates of Marine Bacteria

The interspecific variability in the sensitivity of marine bacterial isolates to UV-B (295- to 320-nm) radiation and their ability to recover from previous UV-B stress were examined. Isolates originating from different microenvironments of the northern Adriatic Sea were transferred to aged seawater and exposed to artificial UV-B radiation for 4 h and subsequently to different radiation regimens excluding UV-B to determine the recovery from UV-B stress. Bacterial activity was assessed by thymidine and leucine incorporation measurements prior to and immediately after the exposure to UV-B and after the subsequent exposure to the different radiation regimens. Large interspecific differences among the 11 bacterial isolates were found in the sensitivity to UV-B, ranging from 21 to 92% inhibition of leucine incorporation compared to the bacterial activity measured in dark controls and from 14 to 84% for thymidine incorporation. Interspecific differences in the recovery from the UV stress were also large. An inverse relation was detectable between the ability to recover under dark conditions and the recovery under photosynthetic active radiation (400 to 700 nm). The observed large interspecific differences in the sensitivity to UV-B radiation and even more so in the subsequent recovery from UV-B stress are not related to the prevailing radiation conditions of the microhabitats from which the bacterial isolates originate. Based on our investigations on the 11 marine isolates, we conclude that there are large interspecific differences in the sensitivity to UV-B radiation and even larger differences in the mechanisms of recovery from previous UV stress. This might lead to UV-mediated shifts in the bacterioplankton community composition in marine surface waters.     

Effect of bovine manure on fecal coliform attachment to soil and soil particles of different sizes

Manure-borne bacteria can be transported in runoff as free cells, cells attached to soil particles, and cells attached to manure particles. The objectives of this work were to compare the attachment of fecal coliforms (FC) to different soils and soil fractions and to assess the effect of bovine manure on FC attachment to soil and soil fractions. Three sand fractions of different sizes, the silt fraction, and the clay fraction of loam and sandy clay loam soils were separated and used along with soil samples in batch attachment experiments with water-FC suspensions and water-manure-FC suspensions. In the absence of manure colloids, bacterial attachment to soil, silt, and clay particles was much higher than the attachment to sand particles having no organic coating. The attachment to the coated sand particles was similar to the attachment to silt and clay. Manure colloids in suspensions decreased bacterial attachment to soils, clay and silt fractions, and coated sand fractions, but did not decrease the attachment to sand fractions without the coating. The low attachment of bacteria to silt and clay particles in the presence of manure colloids may cause predominantly free-cell transport of manure-borne FC in runoff.     

Effect of Bovine Manure on Fecal Coliform Attachment to Soil and Soil Particles of Different Sizes

Manure-borne bacteria can be transported in runoff as free cells, cells attached to soil particles, and cells attached to manure particles. The objectives of this work were to compare the attachment of fecal coliforms (FC) to different soils and soil fractions and to assess the effect of bovine manure on FC attachment to soil and soil fractions. Three sand fractions of different sizes, the silt fraction, and the clay fraction of loam and sandy clay loam soils were separated and used along with soil samples in batch attachment experiments with water-FC suspensions and water-manure-FC suspensions. In the absence of manure colloids, bacterial attachment to soil, silt, and clay particles was much higher than the attachment to sand particles having no organic coating. The attachment to the coated sand particles was similar to the attachment to silt and clay. Manure colloids in suspensions decreased bacterial attachment to soils, clay and silt fractions, and coated sand fractions, but did not decrease the attachment to sand fractions without the coating. The low attachment of bacteria to silt and clay particles in the presence of manure colloids may cause predominantly free-cell transport of manure-borne FC in runoff.     

Role of endothelium-derived relaxing factors in the renal response to vasoactive agents in hypothyroid rats

This study analyzed the role of nitric oxide (NO) and endothelium-derived hyperpolarizing factor (EDHF) in the abnormal renal vascular reactivity of hypothyroid rats. Renal responses to vasoconstrictors [VC: phenylephrine (PHE) and ANG II] and vasodilators [VD: ACh, sodium nitroprusside (SNP), and papaverine (PV)] were studied in kidneys from control and hypothyroid rats under normal conditions and after NO or EDHF blockade. NO was blocked by the administration of Nomega-nitro-l-arginine methyl ester (l-NAME) and EDHF by the administration of tetraethylammonium (TEA) or by an increased extracellular K+. The response to VC was also evaluated after endothelium removal. Hypothyroid kidneys showed reduced responsiveness to PHE and a normal response to ANG II. l-NAME and TEA administration produced an increased sensitivity to PHE and to ANG II in control preparations. l-NAME also increased the response to PHE in hypothyroid kidneys, but the differences between control and hypothyroid kidneys were maintained. TEA administration did not change the response to either VC in hypothyroid preparations. In endothelium-removed preparations, TEA was unable to increase pressor responsiveness to VC. Hypothyroid kidneys showed reduced responsiveness to ACh and SNP and normal response to PV. The differences between hypothyroid and control preparations in the responses to ACh and SNP were maintained after l-NAME or increased K+. In conclusion, this study shows that 1) the attenuated response to PHE in hypothyroidism is not related to an increased production of endothelium-derived relaxing factors NO and EDHF; 2) the response to VC in hypothyroid preparations is insensitive to EDHF blockade; and 3) hypothyroid preparations have a reduced reactivity to the NO donor, and NO-independent vasodilatation remains unaffected.     

Specific residues within the alpha 2 integrin subunit cytoplasmic domain regulate migration and cell cycle progression via distinct MAPK pathways.

The alpha(2) integrin subunit cytoplasmic domain is necessary for epidermal growth factor (EGF)-stimulated chemotactic migration and insulin-dependent entry into S-phase of mammary epithelial cells adherent to type I collagen. Truncation mutants revealed that the seven amino acids, KYEKMTK, in addition to the GFFKR motif were sufficient for these functions. Mutation of tyrosine 1134 to alanine inhibited the ability of the cells to phosphorylate p38 MAPK and to migrate in response to EGF but had only a modest effect on the ability of the cells to induce sustained phosphorylation of the ERK MAPK, to up-regulate cyclin E and cdk2 expression, and to enter S-phase when adherent to type I collagen. Conversely, mutation of the lysine 1136 inhibited the ability of the cells to increase cyclin E and cdk2 expression, to maintain long term phosphorylation of the ERK MAPK, and to enter S-phase but had no effect on the ability of the cells to phosphorylate the p38 MAPK or to migrate on type I collagen in response to EGF. Methionine 1137 was essential for both migration and entry into S-phase. Thus, distinctly different structural elements of the alpha(2) integrin cytoplasmic domain are required to engage the signaling pathways leading to cell migration or cell cycle progression.     

《动物生物学》教学对生命科学发展和人才培养的作用

动物生物学是揭示动物生命活动规律的科学。作为生命科学专业本科学生最早接触到的主干课程之一,动物生物学的教学对于学生了解生物学的基本概念和基础知识、构建生命科学的知识体系和思维方式、培养和巩固专业兴趣十分重要。系统回顾和总结了动物生物学研究对生命学科发展的贡献,阐明了动物生物学教学对生命科学人才培养与学科建设的作用,引起广大的生物学教学工作者和管理者对动物生物学教学的重视,促进传统重要基础课程的建设与发展。     

Transmitter-Induced Calcium Responses Differ in Astrocytes Acutely Isolated from Rat Brain and in Culture

Abstract: Glial fibrillary acid protein (GFAP)-positive astrocytes isolated from the cerebral cortices of 3–10-day-old rats frequently showed increased intracellular Ca²⁺ concentration responses to l -glutamate and glutamate analogues. However, few of the acutely isolated cells responded to ATP, and no such cells responded to serotonin [5-hydroxytryptamine (5-HT)]. The same cell that failed to respond to ATP or 5-HT often responded to glutamate. Culturing acutely isolated cells in media containing horse serum decreased Ca²⁺ responses to glutamate but increased the responses to ATP and induced responses to 5-HT. In primary cultures prepared from the cerebral cortices of 1-day-old rats and cultured in horse serum, fewer of the cells responded to glutamate, but almost all cells responded to ATP and 5-HT. The lack of, or limited response to, 5-HT or ATP in the acutely isolated cells seems unlikely to be due to selective damage to the respective receptors because acutely isolated GFAP-negative cells showed responses to ATP, several different proteases and mechanical dissociation yielded cells that also responded to glutamate but not to ATP, and exposure of primary cultures to papain did not abolish Ca²⁺ responses to several transmitters. The responses of the acutely isolated cells to glutamate but limited or lack of responses to ATP and 5-HT also correspond to what has been seen so far for astrocytes in situ. Thus, the present studies provide direct evidence that some of the receptors seen in primary astrocyte cultures may reflect a response to culture conditions and that, in the context of the relevant information so far available, acutely isolated astrocytes seem to reflect better the in vivo state.     

A Biosemiotic Perspective of the Resource Criterion: Toward a General Theory of Resources

Describing resources and their relationships with organisms seems to be a useful approach to a ‘unified ecology’, contributing to fill the gap between natural and human oriented processes, and opening new perspectives in dealing with biological complexity. This Resource Criterion defines the main properties of resources, describes the mechanisms that link them to individual species, and gives a particular emphasis to the biosemiotic approach that allows resources to be identified inside a heterogeneous ecological medium adopting the eco-field model. In particular, this Criterion allows to couple matter, structured energy and information composing the ecological systems to the biosemiotic and cognitive mechanisms adopted by individual species to track resources, transforming neutral surroundings into meaningful species-specific Umwelten. The expansion of the human semiotic niche that is a relevant evolutionary process of the present time, assigns the role of powerful and efficient agency to the Resources Criterion to evaluate the effect of human intrusion into the natural systems with habits of key stone species, under the challenge of a growing use of alloctonous, immaterial and symbolic resources of the actual globalized societal models. The Resource Criterion interprets the ecological dynamics contributing to complete the epistemology of the ecology, to open a bridge toward economy and other societal sciences, and to contribute to formulate a General Theory of Resources.     

上下视野空间选择性注意的ERP研究

该文主要研究上、下视野空间选择性注意早期所诱发的ＥＲＰ反应,探讨注意上、下视野视觉信息处理的特征与差别。１０名被试的主要实验果为：１）对上、下视野的选择注意产生类似于注意左、右视野时Ｐ１、Ｎ１,Ｐ２的相对增强;２）偶极子定位显示,上、下视野刺激的早期注意反应（Ｐ１）以交叉方式投射到枕区,即下视野刺激的注意反应偏向枕区的背侧,而上视野刺激的注意反应偏向枕区的腹侧;３）上下视野的早期注意反应（Ｐ１）具     

On an infrastructure to support sharing and aggregating pre- and post-publication systems biology research data

The move towards in silico experimentation has resulted in the use of computational models, in addition to traditional experimental models, to generate the raw data that is analysed and published as research findings. This change requires new methods to be introduced to facilitate independent validation of the underlying models and the reported results. The promotion of co-operative research has the potential to help to both validate results and explore wider problem areas. In this paper we leverage and extend two existing software frameworks to develop an infrastructure that has the potential to both promote the sharing of data between researchers pre-publication and enable access to the data for interested parties post-publication. The pre-publication sharing of data would enable larger problem spaces to be explored by distributed research groups; enabling access to the data post-publication would allow reviewers and the wider community to independently verify the published results which would, in the longer term, help to increase confidence in published results. The framework is used to perform reproducible and numerically validated individual-based computational experiments into the onset of colorectal cancer. Existing results are verified and new insights into the top-down versus bottom-up hypothesis of colorectal crypt invasion are given.     

水稻品种对美国稻瘟病小种IB-33、IB-45和IE-1的抗性遗传

1995年10月至1997年11月,在美国阿肯色大学水稻研究推广中心,用水稻品种LA110和Jasmine-85与水稻品种Teqing、Katy、Mars、LaGrue和Newbonnet进行不完全双列杂交,对其杂交后代和亲本用美国3个主要稻瘟病菌小种(以下简称小种)IB-33、IB-45和IE-1进行接种鉴定和遗传分析研究.结果表明:亲本LA110、Jasmine-85、Teqing抗所有3个小种.Katy抗小种IB-45和IE-1,感小种IB-33.Mars抗小种IE-1,感小种IB-33和IB-45.LaGrue感所有3个小种.Newbonnet抗小种IB-45,感小种IB-33和IE-1.所有抗病亲本的抗病基因,其F1分别对相应小种呈现显性抗病性.抗病亲本杂交,LA110与Jasmine-85对小种IB-33,LA110与Teqing、Jasmine-85对小种IE-1,及Jasmine-85与Teqing对小种IE-1,是等位的抗病基因.LA110与Teqing对小种IB-33,及Jasmine-85与Teqing对小种IB-33,分别存在三对独立遗传的显性抗病基因.LA110与Teqing、Katy、Newbonnet、Jasmine-85对小种IB-45,Jasmine-85与Teqing、Katy、Newbonnet对小种IB-45,LA110与Katy、Mars对小种IE-1,Jasmine-85与Katy、Mars对小种IE-1,分别存在两对独立遗传的显性抗性基因.抗病亲本LA110或Jasmine-85与感病亲本Mars对小种IB-33,抗病亲本LA110与感病亲本Mars对小种IB-45,具有两对显性互补抗病基因,当两对显性抗病基因同时存在时,表现出抗性.抗病亲本LA110或Jasmine-85与感病亲本Katy、LaGrue、Newbonnet对小种IB-33,抗病亲本LA110与感病亲本LaGrue对小种IB-45,抗病亲本Jasmine-85与感病亲本Mars、LaGrue对小种IB-45,抗病亲本LA110或Jasmine-85与感病亲本LaGrue、Newbonnet对小种IE-1,分别存在一对显性抗病基因.两个亲本正、反交的遗传表现一致.本文也讨论了LA110、Teqing和Jasmine-85三个抗病品种在美国水稻抗病育种中利用的可能性.     

短季棉早熟性的遗传效应及其与环境互作研究

以熟期不同的9个棉花品种为亲本,按部分双列杂交配制46个组合的F1、F2,在3个不同生态环境条件下,研究了7个早熟相关性状的遗传效应及其与环境互作。结果表明:短季棉7个早熟相关性状的遗传均以加性效应为主,同时存在着显性效应,对于播种-现蕾、播种-开花和现蕾-开花还存在着上位性效应;短季棉各早熟性状的遗传效应与环境互作显著。生育期、播种-开花的狭义遗传率均较高,分别为66.1%和49.1%,且与环境互作效应较小,而果枝始节和播种-现蕾的遗传率最低,分别为19.8%和18.8%,且与环境互作达到极显著水平,现蕾-开花、开花-吐絮和株高这3个性状的遗传率及其与环境互作居中。由此说明:早熟性的遗传受环境影响较大,在生态条件差异较大的育种地点,以果枝始节和播种-现蕾作为早熟性指标进行异地选择是不可靠的,而以生育期、开花期为早熟性选择指标是比较可行的。