Separation of histones from Physarum polycephalum by ion-paired, reverse-phase high-performance liquid chromatography

A rapid, one-step method for the efficient purification of murine monoclonal antibodies from tissue culture supernatants is described. This process is based on affinity chromatography on protein A-Sepharose columns. It was found that murine monoclonal antibodies raised against tick-borne encephalitis virus frequently eluted at more than one pH value and these pH values did not always correspond to those of antibodies of the same subclass from polyclonal mouse sera. The two populations of antibody molecule eluting at different pH values showed no variation in molecular weight, isoelectric profiles, specific enzyme-linked immunosorbent assay titer, or antibody subclass.     

Gradient analysis of reversed treelines and grasslands of the Valles Caldera,New Mexico

Objective: : Treeless meadows and parks are widespread but poorly understood features of the montane vegetation of the western USA. These communities frequently form reversed treelines where grassy valleys occur below forested slopes above. Our purpose was to assess the environmental correlates of such treelines, as well as patterns in the composition and diversity of grasslands and forest margins in the Valles Caldera National Preserve. Location: Valles Caldera National Preserve (35°50′‐36°00’ N, 106°24′‐106°37’ W, 2175–3150 m), Jemez Mountains, New Mexico, USA. Methods: We conducted a gradient analysis based on 200 nested quadrats on transects crossing reversed treelines and spanning the compositional heterogeneity of grasslands. We used cluster analysis and non‐metric multidimensional scaling to assess relationships between compositional variation and environmental variables. Results: We found strong, highly significant relationships of the vegetation to gradients in slope inclination, soil texture, moisture, nutrient availability, and nighttime minimum temperatures. Reversed treelines are most strongly associated with shifts in the thermal regime, exhibit weaker relationships with soil texture and nutrient content, and show no relationship with gravimetric soil moisture. Gradients in aspect, soil moisture, and annual mean temperature are associated with compositional variation within grasslands and forest margins. Conclusions: Lower nightly minimum temperatures and fewer consecutive frost‐free days resulting from cold‐air drainage may prevent tree seedling establishment in valley bottoms via photo‐inhibition, tissue damage, or frost heaving. Fine‐textured soils may also impede tree seedling establishment in valley bottoms. These findings lay the groundwork for experimental and physiological tests of these potential causes of these reversed treelines.     

Assessment of Multiple Ordinal Endpoints

Ranking multivariate ordinal data and applying a non‐parametric test is an analytical approach commonly employed to compare treatments. We study three types of ranking and demonstrate how to combine them. The ranking methods rest upon partial orders of the multidimensional measurements or upon the sum of ranks. Since their usage is simple as regards statistical assumptions and technical realization, they are also adapted for health professionals without deep statistical knowledge. Our goal is discussing differences between the approaches and disclosing possible statistical consequences of their usage (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Exact Tests using Two Correlated Binomial Variables in Contemporary Cancer Clinical Trials

New therapy strategies for the treatment of cancer are rapidly emerging because of recent technology advances in genetics and molecular biology. Although newer targeted therapies can improve survival without measurable changes in tumor size, clinical trial conduct has remained nearly unchanged. When potentially efficacious therapies are tested, current clinical trial design and analysis methods may not be suitable for detecting therapeutic effects. We propose an exact method with respect to testing cytostatic cancer treatment using correlated bivariate binomial random variables to simultaneously assess two primary outcomes. The method is easy to implement. It does not increase the sample size over that of the univariate exact test and in most cases reduces the sample size required. Sample size calculations are provided for selected designs.     

Non-A, non-B hepatitis-related hepatocellular carcinoma in a chimpanzee

Epidemiology has indicated the possible association of non-A, non-B hepatitis (NANBH) with hepatocellular carcinoma (HCC) in man, but there are no means for confirmation. Chimpanzees are recognized models for studying hepatitis B and NANBH, and may become carriers of both. The first case of HCC to be reported in chimpanzees was found after longitudinal study of a hepatitis B-free chimpanzee 7 years after inoculation with human plasma from a patient reported to have chronic NANBH.     

Bacterial iturins mediate biocontrol activity of Bacillus sp. against postharvest pear fruit‐rotting fungi

A potential antagonist, Bacillus sp. LYLB4 isolated from pear fruits, was tested for its antifungal activity against postharvest pear pathogens. LYLB4 had a remarkable antifungal effect on Botryosphaeria dothidea. Although it showed a weak inhibition effect on the growth of Rhizopus stolonifer on potato dextrose agar (PDA) plates, LYLB4 almost completely destroyed R. stolonifer during direct contact in potato dextrose broth (PDB). LYLB4 treatment was able to significantly reduce disease incidence (by 68.9% and 100%, respectively) and lesion diameter (by 68.7% and 100%, respectively) of ring rot caused by B. dothidea and soft rot caused by R. stolonifer in pears. LYLB4 also suppressed several other phytopathogens in vitro, suggesting a broad‐spectrum antagonistic activity against fungal pathogens. 16S rRNA and gyrA sequence analysis indicated that LYLB4 is closely related to B. velezensis. Genome mining indicated that LYLB4 had 11 secondary metabolites encoding clusters, but that the surfactin and fengycin gene clusters may not be functional because of a large deletion. Matrix‐assisted laser desorption ionization‐time of flight mass spectra (MALDI‐TOF‐MS) demonstrated that iturins were the major lipopeptides, and that C₁₆/C₁₇ Bacillomycin D synthesis was stimulated when LYLB4 was co‐cultured with B. dothidea compared to the control. Overall, these results demonstrate that the main biocontrol mechanism adopted by LYLB4 could be through the production of toxic metabolites and direct contact with pathogens.     

Changing climate and historic‐woodland structure interact to control species diversity of the ‘Lobarion’ epiphyte community in Scotland

Question: How will changing climate and habitat structure interact to control the species diversity of lichen epiphytes? Location: Scotland. Method: Species richness (=diversity) of the epiphyte lichen community known as Lobarion (named after Lobaria pulmonaria) was quantified for 94 Populus tremula stands across Scotland, and compared in a predictive model to seven climate variables and eight measures of woodland structure. An optimum model was selected and used to project Lobarion diversity over the geographic range of the study area, based on IPCC climate change scenarios and hypothetical shifts in woodland structure. Results: Species diversity of the Lobarion community was best explained by three climate variables: (1) average annual temperature; (2) autumn and winter precipitation; in combination with (3) historic‐woodland extent. Projections indicate a positive effect of predicted climate change on Lobarion diversity, consistent with the physiological traits of cyanobac‐terial lichens comprising the Lobarion. However, the general response to climate is modified significantly by the effect on diversity of historic‐woodland extent. Conclusions: Historic‐woodland extent may exert an important control over local climate, as well as impacting upon the metapopulation dynamics of species in the Lobarion. In particular, a temporal delay in the response of Lobarion species to changed woodland structure is critical to our understanding of future climate change effects. Future Lobarion diversity (e.g. in the 2050s) may depend upon the interaction of contemporary climate (e.g. 2050s climate) and historic habitat structure (e.g. 1950s woodland extent). This is supported by previous observations for an extinction debt amongst lichen epiphytes, but suggests an extension of simple climate‐response models is necessary, before their wider application to lichen epiphyte diversity.     

五羟色胺在睡眠-觉醒中作用

五羟色胺(5-hydroxytryptamine,5-HT)又称为血清素(serotonin)广泛存在于机体多种组织。神经系统内的五羟色胺属于单胺类神经递质,与很多生理功能有关,参与对摄食、性行为、神经内分泌、疼痛感知、学习记忆和情绪、睡眠-觉醒等生理过程的调控。新近基于电生理、神经化学、分子生物学和神经药理学研究方法发现,五羟色胺和睡眠觉醒过程特别是觉醒过程密切相关,在促进觉醒、抑制快动眼睡眠方面有重要作用。本文介绍了五羟色胺在睡眠-觉醒周期中作用研究的最新进展。     

复方苦参注射液联合伊班膦酸钠治疗非小细胞肺癌骨转移癌疼痛的临床观察

目的：探讨复方苦参注射液联合伊班膦酸钠治疗非小细胞肺癌骨转移癌疼痛的临床观察。方法：选取宜昌市中心人民医院2010年3月至2012年3月收治的非小细胞肺癌骨转移患者98例,根据其治疗方式的不同,分为对照组和治疗组。对照组患者采用伊班膦酸钠进行治疗,治疗组患者采用复方苦参注射液联合伊班膦酸钠进行治疗,比较2组患者的近期疗效、疼痛缓解、KPS评分改善情况。结果：患者近期疗效比较结果显示,治疗组患者部分缓解的例数（百分比）及总有效率要明显优于对照组,且差异有统计学意义（P＜0．05）。治疗组Karnofsky评分改善的例数（百分比）要明显多余对照组,且差异有统计学意义（P＜0．05）。疼痛缓解情况比较分析显示,治疗组患者完全缓解例（百分比）及总的缓解率要明显优于对照组,且差异有统计学意义（P＜0．05）。2组患者不良反应发生情况差异无统计学意义（P＞0．05）。结论：复方苦参注射液联合伊班膦酸钠对非小细胞肺癌骨转移癌疼痛具有明显的作用,能够有效的减轻患者的疼痛,值得在临床上推广应用。     

On testing simultaneously non-inferiority in two multiple primary endpoints and superiority in at least one of them

In a clinical trial with an active treatment and a placebo the situation may occur that two (or even more) primary endpoints may be necessary to describe the active treatment's benefit. The focus of our interest is a more specific situation with two primary endpoints in which superiority in one of them would suffice given that non-inferiority is observed in the other. Several proposals exist in the literature for dealing with this or similar problems, but prove insufficient or inadequate at a closer look (e.g. Bloch et al. (2001, 2006) or Tamhane and Logan (2002, 2004)). For example, we were unable to find a good reason why a bootstrap p-value for superiority should depend on the initially selected non-inferiority margins or on the initially selected type I error alpha. We propose a hierarchical three step procedure, where non-inferiority in both variables must be proven in the first step, superiority has to be shown by a bivariate test (e.g. Holm (1979), O'Brien (1984), Hochberg (1988), a bootstrap (Wang (1998)), or L?uter (1996)) in the second step, and then superiority in at least one variable has to be verified in the third step by a corresponding univariate test. All statistical tests are performed at the same one-sided significance level alpha. From the above mentioned bivariate superiority tests we preferred L?uter's SS test and the Holm procedure for the reason that these have been proven to control the type I error strictly, irrespective of the correlation structure among the primary variables and the sample size applied. A simulation study reveals that the performance regarding power of the bivariate test depends to a considerable degree on the correlation and on the magnitude of the expected effects of the two primary endpoints. Therefore, the recommendation of which test to choose depends on knowledge of the possible correlation between the two primary endpoints. In general, L?uter's SS procedure in step 2 shows the best overall properties, whereas Holm's procedure shows an advantage if both a positive correlation between the two variables and a considerable difference between their standardized effect sizes can be expected.